Hydrophilic surfaces carrying temporary protective covers

The present invention provides a temporary protective cover for a substrate, such as glass. In particular, the present invention provides a temporary protective cover that can be applied to the surface of a substrate to protect the surface from contamination.

[Background Technology] It is difficult to prevent the accumulation of contaminants from the manufacturing environment on glass or other substrates immediately after manufacturing. This type of manufacturing environment generally contains organics and other residues that contaminate the substrate to be manufactured. For example, various solvents, cured products and sealants used in the production of glass and glass products produce residues that accumulate on the surface of the glass to be produced. The air in the manufacturing plant also contains vapors that condense on the manufactured glass or contaminate the glass. For example, silicone is commonly used as a sealant in the manufacture of insulating glass units (IG units). Silicone releases gas for a considerable period of time immediately after deposition. As a result, the silicone residue accumulates on the glass simply by exposing it to the surrounding manufacturing environment. On the contrary, prevention of such silicone contamination has proved to be very difficult. Moreover, it is extremely difficult to remove silicone contaminants.

[0003] Contamination also occurs in some other process during the manufacturing process. For example, a glass sheet is generally transported across a roller when coated, but the bottom surface of the glass sheet makes supportive contact with the roller, which causes a small amount of impurities or traces to adhere to the glass. Such contamination is very minimal but undesirable and should be avoided as much as possible. The handling equipment used in the manufacture of glass products also leaves traces on the glass. For example, vacuum suction cups are commonly used to handle glass sheets, but this handling has also been found to leave traces of the suction cup on the surface of the glass, at least in some cases. Stickers and other markings also apply during the manufacture of glass. While these stickers and markings are easily removed, it is difficult to ensure that they do not leave a lasting effect on the glass surface after removal.

[0004] Glass sheets and other substrates are exposed to other sources of contamination even after they have been shipped from the manufacturing plant. For example, glassware is exposed to various storage and transportation environments before reaching its final destination. As in the case of manufacturing plants, the storage environment and transportation environment also contain residues and vapors that accumulate in the product and contaminate the product. For example, IG units and other products in storage and transportation environments contain silicone sealants and other substances that release gas for a considerable period of time. Of course, many of these environments are out of the control of the manufacturer. In this way, the manufacturer can control the internal environment of his own manufacturing factory or storage factory, but adjusts the environment to which the product or the like is exposed before delivering the glass product or the like to the final consumer. That is very difficult.

[0005] Contamination also occurs during the installation or final work of glassware. The most well-known contamination for new homeowners occurs when some of the paint inadvertently adheres to the window glass when painting the window frame. Installers and painters can take measures to temporarily mask the surface of adjacent glass, for example by applying "masking tape", but it is difficult to mask the entire surface of the glass. .. For this reason, some of the unmasked surface areas are still susceptible to unintended paint spills and drips. Furthermore, since these masking tapes are adhered using an adhesive, it is difficult to prevent the adhesive residue from remaining on the glass after the tape is peeled off.

[0006] Such sources of contamination make the manufacture, transport, installation and finishing of glass and other substrates free of surface contamination significantly difficult. The simplest solution to this problem is to simply remove the contaminants on the surface by washing the contaminated surface with water or other cleaning methods. For example, various polishes and etchants are used to remove paint contaminants from the window pane. A method of scraping paint or the like from glass using a leather blade is also known. However, such aggressive cleaning methods also remove some of the glass, leaving cloudy or scratched areas. Even with this type of aggressive cleaning method, it is practically impossible to remove certain contaminants (eg, silicone, etc.).

[0007] Another solution is to temporarily protect the substrate over a potential period of contamination. In the past, attempts have been made to protect glass with removable paper and plastics. Generally, such papers and plastics are removed by mechanically stripping them from the substrate. The following US patent specification discloses related techniques: No. 1,256,818 (Nile), No. 5,107,643 (Svensen), No. 5,599,422 (Jr. Adams et al.) And No. 5,866,260 (Jr.). Adams et al.) (The disclosures of these patent specifications are also part of this specification).

[0008] However, protective papers and plastics have many drawbacks. For example, these are commonly applied with adhesives. Not only does this type of adhesive react with the glass and make it difficult to remove, but it can also change the surface properties of the glass. This is especially problematic when masking the glass for extended periods of time or when the masked glass is exposed to high temperatures or substantial radiation (eg, sunlight radiation). Certain paper and plastic components, such as silicone-containing components, react with glass in this process. Adhesive-free applications, such as those based on static adhesiveness, are also possible. However, the papers and plastics applied by such methods are not as safe as expected and may come off during handling. In addition, the protective papers and plastics that are removed generate additional waste that must be disposed of or recycled, which requires additional labor and expense.

[0009] There are also methods of temporarily protecting the glass by applying the liquid coating composition by various wet deposition methods (eg, coating method, dipping method, spraying method, etc.). The resulting coatings vary in composition, many of which are polymeric materials that are removed by stripping or washing with water. The following patent documents are exemplified in this regard: US Pat. Nos. 5,453,459 (Roberts), 5,866,199 (Swidler), 6,124,044 (Swidler), PCT Publication WO 00/50354 (McDonald's) and WO 01/02496. No. (Medwick et al.) Specifications. The literature of Medwick et al. Also discloses sputtered carbon-containing coatings that can be used to provide temporary protection for glass. It is said that this coating can be removed by burning. For example, Medwick et al. Have stated that the coating is oxidized and removed during quenching. However, all these attempts are far from ideal.

[0010] The limitations of these attempts become more apparent when considering the full range of machining processes that a typical window can withstand. Glass sheets are formed by many methods, the most common of which is the float glass process. In this method, the basic components of the glass are combined and then heated in a furnace at a temperature on the order of 2900 ° F to melt the glass. The glass ribbon is suspended on top of a molten tin bath, cooling is initiated in the bath and then machined to the desired width and thickness. The resulting glass is cut into smaller sheets.

[0011] The glass sheet can be coated with various different coatings using various different coating methods. The spatter deposition method is a general method for coating a substrate having a large surface area, for example, architectural glass or the like. When the glass sheet is coated by the sputtering deposition method, the glass sheet is transported into the sputtering chamber. Generally, the glass is conveyed through a series of connected sputtering chambers (ie, sputtering lines). Each sputtering chamber has a controlled sputtering atmosphere. As the glass sheet is conveyed through the sputtering line, the desired coating is sputtered onto the glass surface. At the exit of the sputtering line, the glass is released from the controlled sputtering atmosphere and exposed to the surrounding glass processing atmosphere. From this point on, the accumulation of environmental contaminants on the coated glass begins.

[0012] Thus, the coated glass is generally susceptible to contamination when released from the controlled coating environment. As a result, it is desirable to temporarily protect the coated substrate when coating the substrate. For example, it is desirable to apply a temporary protective cover to the sputter-coated glass before removing the glass from the sputtering line.

[0013] It is difficult to apply a paper, plastic or liquid coating composition inside a sputtering chamber. For example, the high temperature of the substrate that occurs during sputtering poses a problem for such applications. During sputtering, the glass generally reaches temperatures on the order of 100-200 ° C, and in some cases may reach higher temperatures. Such temperatures exceed the softening points of many plastics and many adhesives used to apply paper or plastics. Moreover, conventional sputtering chambers are not designed to be compatible with wet deposition methods. Therefore, it is not practical, if not impossible, to apply these protective materials in a sputtering chamber. Although it is possible to apply these protective materials in a sputtering chamber, the protective material cannot withstand the processing conditions to which many substrates are attached after being coated with the protective material.

[0014] The glass released from the coating atmosphere (for example, the atmosphere in the sputtering chamber) is generally covered with a so-called "separator". Common separators contain a protective powder (eg, adipic acid powder) that protects the glass from corrosion due to moisture. The powder generally contains small beads (eg, nylon beads) that separate the sheets when the glass sheets are stacked on top of each other. This type of bead prevents adjacent surfaces from coming into contact with each other in a stacked state, thereby minimizing wear and other damage.

[0015] As mentioned above, glass sheets are often assembled into IG units. As the first step in this process, the separator is generally washed away from the glass sheet. This process is simply performed by passing the glass sheet through the industrial glass washer. Industrial glass cleaners use water (sometimes hot water) and, if desired, detergent. Most protective papers and plastics cannot be expected to remain after passing through an industrial glass washer. Furthermore, the deterioration of these protective materials forms problematic waste in the washer, which clogs the washer and complicates its maintenance. Furthermore, many protective materials used in liquid form are water soluble. Therefore, it is desirable to provide a temporary protective cover that can withstand industrial cleaning.

[0016] The coated glass is also subjected to various high temperature steps, such as heat quenching and bending. For example, during the quenching process, the glass is typically heated for a considerable period of time (eg, for several hours) at temperatures on the order of about 600 ° C (1112 ° F). Unfortunately, most protective papers, plastics and polymer materials are burned out or at least significantly degraded during the high temperature process. Similarly, the carbon-containing protective coatings described in Medwick et al.'S literature are said to be burned out during the quenching process. Since the hardened glass is exposed to sources of contamination after quenching, for example in subsequent storage, transport, installation and finishing, it is useful to provide a temporary protective cover that is resistant to quenching.

(Disclosure of the Invention) (Technical Issues to be Solved by the Invention) It is desirable to provide a temporary protective cover that can be applied to a coated substrate as part of the coating process. For example, it is useful to provide a temporary cover that can be applied to sputter-coated glass in a controlled sputtering environment. It is particularly desirable to provide a temporary cover that exhibits sufficient resistance over the entire range of processing processes that glass and other substrates generally withstand. For example, it is effective to provide a temporary cover that is resistant to industrial glass cleaning and the like. It is particularly desirable to provide a temporary cover that is resistant to high temperature processing (eg, heat quenching and bending). At the same time, it is desirable to provide a temporary cover that can be easily removed after installation, after finishing, or at any stage where it is desired to expose the underlying surface.

A substrate having a durable outer surface (eg, glass, etc.) (the outer surface may be composed of the substrate itself or a coating formed on the substrate. May be), but protected from contamination by forming a temporary protective cover on the durable surface that is disintegrated and removed by cleaning with a cleaning solution that does not disintegrate the durable surface of the substrate. There was found. The cover prevents the durable surface from being contaminated with, for example, silicones used in the window industry. When the cover is no longer needed, it can be easily removed from the durable surface with a cleaning solution (eg, an acidic or alkaline aqueous solution, such as vinegar). Removing the protective cover, which can itself contaminate, exposes the clean, original durable surface of the substrate.

[0019] According to one aspect of the invention, there is provided a substrate having an outer surface that is durable against the cleaning solution of choice. This outer surface is<u style="single">Contains oxides of metals selected from the group consisting of zinc, bismuth, cadmium, iron and nickel</u>It holds a temporary protective cover containing a spatter film, which protects the outer surface from contamination and can be easily removed from the outer surface by cleaning with the cleaning solution.

[0020] According to another aspect of the invention, there is provided a substrate that retains an external coating that is durable against the cleaning solution of choice. The outer coating was sputtered directly onto it<u style="single">Contains oxides of metals selected from the group consisting of zinc, bismuth, cadmium, iron and nickel</u>Holds a temporary protective cover containing the film.<u style="single">Temporary protection</u>The cover protects the outer coating from contamination and is easily removed from the outer coating by cleaning with a cleaning solution of choice.

[0021] According to yet another aspect of the invention, there is provided a substrate having an outer surface that is durable against the cleaning solution of choice. The outer surface protects the surface from contamination.<u style="single">Contains oxides of metals selected from the group consisting of zinc, bismuth, cadmium, iron and nickel</u>Hold a temporary protective cover. The cover is resistant to high temperatures on the order of about 600 ° C and is easily removed from the outer surface by cleaning with a cleaning solution of choice.

[0022] In another aspect of the invention, the insulating glass unit comprising a plurality of panes at intervals, wherein the panes have opposed internal surfaces that limit the space between the panes. Provide a glass unit. At least one of the panes has an outer surface that is resistant to the cleaning solution of choice. The outer surface comprises a temporary protective cover, which comprises a sputter film that protects the outer surface from contamination, but is easily removed from the outer surface by cleaning with a cleaning solution of choice.

[0023] According to another aspect of the present invention, a method for producing a substrate is provided. The method generally includes the step of supplying a substrate having opposite inner and outer surfaces. A durable coating is formed on the outer surface of the substrate. The coating is durable against the cleaning solution selected. The temporary protective cover is sputtered onto a durable coating. The cover contains a material that protects the durable coating from contamination and is easily removed by cleaning with a cleaning solution of choice.

[0024] In another aspect of the present invention, a method for processing a substrate is provided. The processing method comprises preparing a substrate having an outer surface that is resistant to the cleaning solution of choice. The outer surface comprises a temporary protective cover, which comprises a sputter film that protects the outer surface from contamination and is easily removed from the outer surface by cleaning with a cleaning solution of choice. Cleaning the covered outer surface of the substrate with a cleaning solution of choice removes at least a portion of the cover, thereby exposing at least a portion of the outer surface underlying it.

[0025] According to another aspect of the present invention, a window assembly is provided. This assembly includes a window pane with an outer surface that is durable against the cleaning solution of choice. The outer surface carries a temporary protective cover containing a sputter film that is easily removed by cleaning with a cleaning solution of choice. This assembly includes a frame structure in which the panes are fixed by the sealant beads. The sealant bead is directly attached to the periphery of the protective cover on the first side and also. On the second side, it is connected to the frame structure.

[0026] According to yet another aspect of the present invention, a method for processing a substrate is provided. The method includes the step of supplying a substrate having an inner surface and an outer surface. A sputtering line including a sputtering chamber connected in series, and a sputtering line in which a substrate support is arranged in each sputtering chamber is also supplied. The first sputtering chamber has a first lower target located below the support in the first chamber. The second sputtering chamber has a second lower target located below the support in the second chamber. On the support in the first sputtering chamber, the substrate is oriented so that the outer surface of the substrate faces the direction of the first lower target, and the first lower target is sputtered so that the first coating is deposited on the outer surface of the substrate. It is arranged in various manners. The first coating contains a substance that is durable to the cleaning solution selected. On the support in the second sputtering chamber, the substrate is such that the outer surface of the substrate faces toward the second lower target, the second lower target is sputtered, and the second coating is deposited on the first coating. Arranged in a mode. The second coating contains substances that can be easily removed from the first coating by cleaning with the cleaning solution of choice.

[0027] In yet another aspect, the present invention provides a substrate having an outer surface that exhibits high resistance to a desired cleaning solution, such as a glass sheet. The outer surface may be the surface of a substrate, or may be a surface obtained by depositing a coating on the substrate. Surfaces and coatings that do not exhibit sufficient resistance to conventional cleaning methods or the desired cleaning solution are less desirable for use in this embodiment. A temporary protective cover is deposited directly on the outer surface. The cover protects the outer surface from contamination with silicone rubber formulations and the like and is easily disintegrated by the desired cleaning solution (preferably an aqueous solution, most preferably at least a somewhat basic or acidic solution) and washed away from the outer surface. It is a cover with a material and thickness that can be used.

[0028] In yet another aspect, the present invention provides a method that can be used in the manufacture and installation of windows. The method involves (i) imparting an external surface to the window that is resistant to a given cleaning solution, (ii) forming a protective cover on the external surface that protects the surface from contamination, and then (iii). ) A step of flushing the protective cover from the outer surface with a cleaning solution that disintegrates the protective cover but does not damage the outer surface is included.

[0029] FIG. 1 is a schematic cross-sectional view of a substrate having a surface holding a temporary cover according to an aspect of the present invention. FIG. 2 is a schematic cross-sectional view of a substrate having a coated surface holding a temporary cover according to another aspect of the present invention. FIG. 3 is a schematic cross-sectional view of a substrate having two coated surfaces, one of which has a temporary cover according to yet another aspect of the present invention. FIG. 4 is a schematic view of a glass unit insulated and separated by multiple-panes, wherein one coated surface of the pane holds a temporary cover according to still another aspect according to the present invention. It is a cross-sectional perspective view. FIG. 5 is a schematic cross-sectional view of a substrate having two coated surfaces, each of which has a temporary cover according to another aspect of the present invention. FIG. 6 is a schematic cross-sectional view of a substrate having a coated surface, wherein the coated surface holds a temporary cover according to still another aspect of the present invention. FIG. 7 is a schematic configuration diagram of a two-way sputtering chamber for use in one method of the present invention. FIG. 8 is a schematic schematic diagram of a multi-region / bidirectional sputtering chamber for use in another method of the present invention. FIG. 9 is a partial schematic cross-sectional view of a window assembly according to another aspect of the invention. FIG. 10 is a partial schematic cross-sectional view of a window assembly according to yet another aspect of the present invention.

(Best mode for carrying out the invention) Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the attached figure, the same elements are indicated by the same reference numbers. These attachments, which do not necessarily require dimensions, show selected embodiments of the invention, but do not limit the scope of the invention. For the selected elements, the structure, materials, dimensions and manufacturing process are exemplified, but for all other elements, those known to those skilled in the art are used. As will be appreciated by those skilled in the art, the exemplary embodiments presented herein include many suitable alternative embodiments available within the scope of the present invention.

FIG. 1 shows a substrate 10 having an outer surface 12 that holds the temporary protective cover 90 according to the present invention. The outer and inner surfaces of the substrate are indicated by reference numbers 12 and 14, respectively. The indications "inside" and "outside" surfaces in this case are somewhat arbitrary. For example, unless such a requirement is explicitly stated, it does not necessarily have to be the outer or inner surface exposed to the outdoor environment.

Suitable substrates for use in the present invention generally include a particular group of substrates, including flat sheet-like substrates. This type of substrate typically has two main surfaces 12 and 14 that are generally opposed. For example, this type of substrate group includes sheets such as glass. In practice, the temporary protective cover according to the invention can be very conveniently used to protect the glass substrate from contamination. Examples of the glass substrate generally used in the manufacture of glass products (for example, an insulating glass unit) include a type generally called soda-lime glass. Other suitable types of glass include: Alkaline Lime-Silicon Dioxide Glass, Borone-Silicon Dioxydate (silicon) dioxidate) Glass, aluminosilicon dioxydate glass, boron-aluminosilicon dioxydate glass, phosphate glass and fused silicon dioxide glass. The substrate 10 does not have to be transparent. For example, an opaque substrate may be useful. However, for most applications, the substrate is expected to contain a transparent or translucent material, such as glass or clear plastic.

[0033] The temporary cover according to the invention can be used to prevent contamination of virtually any substrate surface or coating. Preferably, the cover is held by a durable outer surface. The durable outer surface may be formed by the substrate itself. Alternatively, the outer surface may be formed by a coating on the substrate. Desirably, the outer surface has good mechanical durability. For example, the surface preferably has sufficient mechanical durability to withstand the rigors of common window cleaning techniques so that it does not suffer damage such as unacceptable scratches. It is also desirable that the durable surface be resistant to being attacked by at least a somewhat acidic or basic cleaning solution (ie, stable in the presence of the cleaning solution). Preferably, the surface exhibits resistance so that it is not attacked by loose acids or bases. Optimal the surface is completely unaffected by contact with loose acids or bases.

Durability Since the outer surface is exposed after removal of the protective cover 90, it is desirable that the outer surface be sufficiently resistant to the exposed environment. In some cases, the outer surface is planned to be exposed to the outdoor environment. In such cases, the outer surface is subject to long-term exposure to external (ie, outdoor) weather conditions, such as contact with periodic rain (ie, somewhat acidic or basic water). It is preferable to show resistance (that is, adaptive resistance). Therefore, it is desirable that the outer surface holding the cover be physically and chemically resistant.

[0035] In the embodiment shown in FIG. 1, the substrate 10 has a temporary protective cover 90 formed directly on the surface of the substrate. That is, the cover 90 is held on the outer surface 12 of the substrate 10. In this embodiment, the inner surface 14 of the substrate 10 is not protected by the cover 90. However, if desired, protective covers 90 may be held on both sides of the substrate, regardless of whether the substrate is completely uncoated or one or both of the surfaces 12 and 14 are coated. For example, in the embodiment shown in FIG. 5, the substrate 10 has a first coating 20 that holds the first cover 90 on the inner surface 14 and a second coating 20 that holds the second cover 90 on the outer surface 12. Have. In such an embodiment, the main surfaces 12 and 14 of the substrate 10 are protected from contamination.

[0036] As described above, the cover 90 according to the present invention can be used extremely conveniently to prevent contamination of the substrate coating. There are virtually no restrictions on the types of coatings that are advantageous for such provisional protection. Therefore, the cover 90 according to the present invention can be used to protect a coating of any kind or property. As described above, it is desirable that the coating present under the protective cover 90 be sufficiently durable to the environment exposed by the removal of the protective cover.

[0037] In the embodiment shown in FIG. 2, the substrate 10 has an outer surface 12 that holds the coating 20 that holds the temporary protective cover 90. The coating 20 may be any desired single layer coating or multilayer film laminate. Although some useful coatings are described below, consideration of the types of coatings available is outside the scope of the present invention. Moreover, one of ordinary skill in the art can select different coatings 20 for different applications without problems.

[0038] The temporary protective cover 90 according to the present invention is useful for protecting a substrate having hydrophilic surface properties. As mentioned above, glass sheets initially having hydrophilic surface properties are contaminated in various manufacturing processes. For example, it has proven surprisingly difficult to produce architectural glass that retains a hydrophilic coating that does not contain substances such as silicone that contaminate the coated glass. Unfortunately, silicones and other contaminants make hydrophilic surfaces undesirably hydrophobic. However, by temporarily protecting the freshly manufactured hydrophilic coating with the cover 90 according to the invention, the manufacturer more reliably guarantees that the final consumer will be able to take advantage of the desired hydrophilic properties of the coating. be able to.

[0039] It is highly desirable to produce a glass that retains a hydrophilic coating. The hydrophilic coating has an affinity for water and tends to spread the adhering water. Surprisingly many attempts have been made to produce glass and other substrates with hydrophilic surface properties. As described in U.S. Patent Applications 09/868542, 09/868543, 09/599301 and 09/572766, hydrophilic coatings are used for architectural glass and other materials. It is particularly advantageous when applied on a substrate (the entire description of these specifications is also part of this specification). For example, such a coating helps maintain a clean appearance over a longer period of time by preventing the formation of water stains.

[0040] In one embodiment, the substrate 10 as shown in FIG. 2 retains the hydrophilic coating 20. In this illustrated embodiment, the hydrophilic coating 20 is formed directly on the outer surface 12 of the substrate 10, but this is not a requirement. As described below, the hydrophilic coating 20 may be formed on one or more films pre-deposited on the substrate 10. The hydrophilic coating 20 carries the temporary protective cover 90 according to the present invention. The illustrated cover 90 is formed directly on the hydrophilic coating 20, but this is not a requirement. In the illustrated embodiment, the inner surface 14 of the substrate 10 does not have a protective cover, but may be provided with a protective cover if necessary.

[0041] The temporary protective cover 90 according to the present invention can be used to conveniently protect any kind of hydrophilic coating or surface contamination. In FIG. 2, the substrate 10 retains the separated hydrophilic coating 20, which is not a requirement of the present invention. For example, the surface of the substrate 10 may itself be hydrophilic. This may be an inherent property of the substrate material, or may be a property obtained by subjecting the substrate 10 to a particular surface treatment. As used herein, the term "hydrophilic" refers to the property of a water-coated coating or surface that allows the water to spread over one surface rather than beading. For example, hydrophilic coatings and surfaces are expected to exhibit contact angles less than about 25 degrees with water in their pre-contaminated state.

[0042] The cover 90 according to the invention can be used in combination with any desired hydrophilic coating. As described below, in a particularly preferred embodiment, the hydrophilic coating 20 is an oxide. However, this is not a requirement and various suitable materials can be used. Preferably, the hydrophilic coating 20 is formed from a material that exhibits a contact angle of less than about 25 degrees to water before exposure to any environmental pollution and after the temporary cover 90 has been removed. ..

[0043] In a particularly preferred embodiment, the hydrophilic coating 20 is a particular preferred water-sheeting coating. Such coatings are described in detail in U.S. Patent Application Nos. 09/868542 and 09/599301, the entire description of which is also part of this specification. .. This coating is made of silicon dioxide, which is advantageous in that it is substantially non-porous. As described below, the outer surface of this silicon dioxide coating may have an irregular surface. Therefore, it is somewhat difficult and inaccurate to make this type of coating a particular thickness. However, an intermediate thickness between about 15 angstroms and about 350 angstroms is preferred, especially an intermediate thickness between about 15 angstroms and about 150 angstroms. The main advantage of this coating, which is obtained at the lowest cost, is believed to be demonstrated at intermediate thicknesses between about 20 angstroms and about 120 angstroms.

[0044] The preferred water ductile coating 20 is preferably formed by sputtering. Sputtering methods and their implementation devices are well known in the art. For example, magnetron sputtering chambers and related equipment are commercially available from numerous manufacturers [eg, Leybold and BOC Coating Technology]. Useful magnetron sputtering chambers and related equipment are also disclosed in U.S. Pat. Nos. 4,166,018 (Chapin) and 5645699 (Siec), and the full description of these specifications is also part of this specification. It forms a part.

[0045] Generally speaking, the magnetron sputtering method involves supplying at least one target formed of a material to be deposited on the substrate 10. In this method, a clean substrate (eg, glass) is placed in the coating chamber. The coating chamber is preferably 10^-⁴Low pressure than torr, more preferably 2x10^-5Exhausted to a lower pressure than torr. The target is negatively charged and a positively charged anode is placed adjacent to the target. By introducing a relatively small amount of the desired gas into the room adjacent to the target, plasma of the gas can be generated. Particles (for example, ions) in the plasma collide with the target to knock out the target constituent material from the target and perform sputtering on the substrate. To facilitate this method, it is known to place a magnet behind the target, which adjusts the plasma to be concentrated near the target's sputtering surface.

Conventional magnetron sputtering methods and related equipment can be used to form the preferred water ductile coating 20. For example, the coating 20 can be deposited by sputtering a silicon dioxide target in an inert atmosphere. However, reliable sputtering of silicon dioxide is extremely difficult. The reason for this is that the target functions as a cathode in the conventional magnetron sputtering method, and silicon dioxide is a weak conductor. As a result, the water ductile coating 20 is preferably deposited using a target containing metallic silicon rather than silicon dioxide. The metallic silicon actually deposited on the substrate can be converted to silicon dioxide by using a sputtering atmosphere containing oxygen.

[0047] The silicon target is preferably not composed of pure silicon. More preferably, the target contains a compound of silicon and aluminum. It is difficult to sputter a pure silicon target in a stable and controlled state. This is because silicon is a semiconductor. As a result, some of the non-conducting silicon dioxide released during sputtering of pure silicon targets is redeposited on the surface of the target as well as on the anode and surrounding shield in the sputtering chamber. This adversely affects the current flow, resulting in the generation of an arc when sputtering continues. Therefore, in order to reduce the generation of arcs, it is preferable that the target contains about 5% of aluminum or the like. Targets with such properties can be obtained from well-known manufacturers, such as Bekaert VDSnv (Dainze, Belgium).

[0048] The atmosphere in the sputtering chamber can be varied to achieve the optimum sputtering rate. When using a silicon target or a silicon-aluminum target, it is preferable to use an oxidizing sputtering atmosphere. Of course, in such cases, the sputtering atmosphere need not be pure oxygen. Conversely, mixtures containing oxygen and an inert gas (eg, argon) tend to increase the sputtering rate. For example, it contains oxygen and up to about 40% (preferably 0-20%) argon and about 3x10.^-3It is believed that the sputtering atmosphere regulated by mbar is sufficient. The power applied to the target is preferably optimized to reduce arc generation and maximize the sputtering rate.

In one manufacturing apparatus that produces good results, a rotating sputtering target made of three silicons doped with about 5% aluminum (a target consisting of about 95% silicon and about 5% aluminum) is used. Then, about 42 kW of electric power is applied to each target. The atmosphere in the sputtering room is about 2.5 ~ 4.5m Torr 100% O₂ May be contained. Alternatively, create an atmosphere containing about 80% oxygen and about 20% argon in about 3x10.^-3You may adjust the pressure to mbar and use it by hand. The substrate 10 can pass near the sputtering target at a rate of about 100-500 inches / minute. Of course, the precise operating conditions applied to the preferred water ductile coating 20 (eg, substrate movement speed, power, plasma composition, target composition, etc.) are such that different thicknesses of the coating 20 are optimally deposited. Can be changed. Given the teachings of the present invention as criteria, one of ordinary skill in the art can readily select and appropriately modify the appropriate operating conditions applied to the water ductile coatings 20 of different thicknesses.

[0050] Thus, in a particularly preferred method of the invention, the preferred water ductile coating 20 moves the substrate 10 beneath a plurality of silicon-aluminum targets and sputters the targets in an oxidizing atmosphere. If desired, the atmosphere may consist solely of oxygen and an inert gas. This is not a requirement, but a sputtering atmosphere with such a composition gives good results. The coating 20 deposited by such a method is expected to consist only of silicon dioxide, but at least when first deposited, a small amount of aluminum or other metal added to the target to increase conductivity. It may be included in the coating.

Silicon dioxide sputter-deposited on the substrate according to the present invention results in a coating having a significantly irregular surface as compared to the uncoated glass surface. According to a photomicrograph of the preferred water ductile coating 20 (the photo is disclosed in US Patent Application No. 09 / 868,542 above), the surface of the coating is spaced apart from the rest of the surface. Characterized by a number of distinct peaks that are significantly sharper than. These micrographs are not representative of the entire surface of such coatings, but suggest that the surface of the water ductile coating 20 formed by the present invention is irregular and substantially non-porous. It is thought that it will be done.

[0052] The visual condition of the glass sheet that retains the preferred water ductile coating 20 is different from the condition of the same glass sheet that does not retain the coating. The glass surface holding the preferred water ductile coating 20 allows water to flow more easily and is significantly easier to clean to the point where no visual streaks or defects are present, as compared to an uncoated glass sheet under the same conditions. can do.

Comparative samples were prepared to accurately compare the preferred water ductile coating 20 and directly comparable glass sheets that do not retain the coating. After thoroughly cleaning the flat, untreated glass pane, it was placed horizontally on a set of rollers. A small piece of square glass was placed on the top surface of the pane and used as a template to cover a portion of the surface of the pane. Move the pane and the template placed on it into the magnetron sputtering chamber, and SiO₂A coating made of (thickness: about 35 angstroms) was deposited. The pane obtained by removing the template has a preferred water ductile coating 20 on most of its surface and has an uncoated area located below the template during sputtering. The other side of the glass, ie SiO₂The side opposite to the side with the coating is covered with an infrared reflective film laminate with low emissivity. The laminate has two silver layers that are isolated from each other and from the glass by a plurality of dielectric layers.

[0054] The partially coated surface of the glass pane was visually observed. With sufficient washing, the boundaries of the uncovered area below the template were virtually undetectable by the naked eye during sputtering. This indicates that the water ductile coating had minimal effect on the basic optical properties of the glass. A fine spray of spray water droplets was applied onto the glass surface using a simple, manually operated spray bottle of the type commonly used to spray household cleaning products. When sprayed water was applied, the boundaries of the uncovered area were easily visually observed. The water on the areas supporting the coating flowed to form a clearly uniform water film, while the areas without the coating exhibited a less uniform appearance.

[0055] A conventional cleaning solution commercially available under the trademark "Windex" is sprayed onto the surface of the glass pane and the surface is exposed to the appearance of an area supporting the water ductile coating using a paper towel. Wipe until dry and no visible streaks. At this point, damp streaks were still visually observed in the uncoated area. Such streaks on the uncovered area are eventually dried without leaving virtually any residual streaks on the glass, but for the average worker these streaks are visually observable. It is considered that the work of wiping the area is continued until it disappears. This means that the time and effort required by the operator to clean the glassware holding the water ductile coating 20 is less than in the cleaning of glassware without such a coating. These results indicate that the preferred water ductile coating 20 makes cleaning the glass with the coating significantly easier than cleaning the uncoated glass.

[0056] As mentioned above, it is extremely convenient for the hydrophilic coating 20 to be formed by sputtering silicon dioxide, but this is not a requirement. Any desirable hydrophilic coating can be used. For example, other useful hydrophilic coatings are described in US Patent Application No. 09/576766, the entire teachings of which are also part of this specification. In addition, one of ordinary skill in the art would wish to use another type of hydrophilic coating that would benefit from the cover 90 according to the invention.

[0057] The cover 90 according to the present invention can also be effectively used to protect the surface of the photocatalyst from contamination. For example, the outer coating 20 in the embodiment shown in FIG. 2 may be a photocatalytic coating. The surface of the photocatalyst is known to chemically decompose organic substances. The advantages of protecting the photocatalytic surface from contamination can be illustrated without a comprehensive overview of photocatalytic activity. In short, it has long been known that certain metal oxides have the property of absorbing ultraviolet light to decompose organic substances such as oils, plant matter, fats and greases. Therefore, the photocatalytic surface exhibits somewhat self-cleaning surface properties. The most potent photocatalytic material is thought to be titania, but other metal oxides are also thought to exhibit photoactivity.

[0058] Glass and other substrates that retain a photocatalytic coating have a wide variety of potential uses. For example, a self-cleaning window is, of course, highly desirable. As is well known to homeowners, it takes a relatively large amount of time to keep windows and other glass surfaces clean. Keeping a few windows clean is not very difficult, but keeping a very large number of windows clean can be a significant burden. For example, cleaning a modern glass office tower requires a significant amount of time and money as it requires regular cleaning by multiple window washer teams. Therefore, the potential benefits of self-cleaning windows are clear.

[0059] Even if a coating having high photocatalytic activity is produced, the photocatalytic properties of the coating are deteriorated due to surface contamination. For example, the surface of a photocatalyst tends to decompose organic pollutants, but the surface generally does not decompose inorganic substances. As a result, photocatalytic windows and the like are susceptible to contamination by inorganic residues. Therefore, a particularly advantageous application of the cover 90 according to the invention is protection from photocatalytic surface contamination. By applying the cover 90 according to the present invention to a photocatalytic coating immediately after production, the manufacturer can protect the coating from contamination during the manufacturing, storage, transportation, mounting and finishing processes.

[0060] A wide variety of coatings can be formed by utilizing various deposition methods. For example, useful photocatalytic coatings are described in each of the following US patent specifications, the entire description of which is also part of this specification: No. 5874701 (Watanabe et al.). , No. 5583866 (Watanabe et al.), No. 5961843 (Hayakawa et al.), No. 6139803 (Watanabe et al.), No. 6191062 (Hayakawa et al.), No. 5939194 (Hashimoto et al.), No. 6013372 (Hayakawa et al.), No. 6090489 (Hayakawa et al.), 6210779 (Watanabe et al.), 6165256 (Hayakawa et al.), 5616532 (Heller et al.), 5849200 (Hayakawa et al.) And 5845169 (Hayakawa et al.). All known covers 90 according to the invention are expected to be useful for protecting virtually any photocatalytic coating, including photocatalytic coatings not currently found. The description of the photocatalytic coating is outside the scope of the present invention. The most suitable photocatalytic coating is believed to contain an inorganic titanium compound, such as an oxide of titanium.

[0061] In a particularly effective embodiment, the photocatalytic coating comprises a sputtered titanium oxide film. Titanium oxide can be sputter-deposited by several methods. First, a target formed of metallic titanium can be sputtered in an oxidizing atmosphere. Unfortunately, this method is extremely slow. Second, the target formed from titanium dioxide can be sputtered in an inert atmosphere. However, since titanium dioxide has a drawback of low conductivity, it is difficult to stably sputter the compound with high power. Therefore, when depositing the photocatalytic titanium dioxide coating according to the present invention using a titanium dioxide target, such a method is preferably limited to the sputtering method at a low power / low deposition rate.

[0062] In a preferred method, the photocatalytic coating according to the invention is deposited by sputtering a stoichiometrically inadequate titanium dioxide target. Such a target is particularly preferable because it has a high conductivity, and can be sputtered at a high speed. Targets with such properties are described in U.S. Patent Application No. 60/262878, the entire description of which is also part of this specification. Targets with such characteristics are known by well-known manufacturers, such as Beckert VDS nv. It is available from the company (Dainze, Belgium). Thus, in a preferred method, the preferred titanium oxide film is deposited by placing the substrate below one or more stoichiometrically inadequate titanium oxide targets. Such targets are most preferably sputtered in a sputtering atmosphere containing argon, oxygen, or a mixture of argon and oxygen. Suitable mixtures contain 70-90% by volume argon and 1-30% by volume oxygen. Stoichiometrically inadequate titanium oxide targets are described in each of the following US patent applications by Van der Straiten, and the full teaching of these specifications is also part of this specification. What it does: 09/024240, 09/024071 and 09/044681.

[0063] The cover 90 according to the present invention is particularly desirable to contain an inorganic substance when it is retained on a photocatalytic coating. For example, the outer coating 20 shown in FIG. 2 may be a photocatalytic coating. As mentioned above, photocatalytic surfaces tend to chemically decompose organic substances. Therefore, if the cover 90 made of organic material is held directly on the photocatalytic coating, the cover 90 may deteriorate as a result of the resolution of the photocatalytic coating. Therefore, in the embodiment in which the protective cover 90 is directly held on the photocatalytic coating 20, the cover 90 preferably contains an inorganic substance that is resistant to the photoactivity of the coating 20.

[0064] In the embodiment shown in FIG. 2, the substrate 10 retains a photocatalytic coating 20 on its outer surface 12, but its inner surface 14 is uncoated. In another embodiment (not shown), the inner surface 14 of the substrate 10 as shown in FIG. 2 has a reflective coating 30. The reflective coating 30 can take any desired form, depending on its desired properties. For example, it is effective to use the infrared reflective coating 30 as described in connection with FIG. Further, it is advantageous to form a temporary protective cover on such a reflective coating.

The substrate 10 shown in FIG. 2 holds the photocatalytic coating 20 directly on its outer surface 12. The photocatalytic coating 20 may be held on a pre-deposited film on the outer surface 12 of the substrate 10. Such a film may contain one or more layers selected to impart the desired properties to the substrate. Aspects having such characteristics will be described in relation to FIG.

[0066] The temporary protective cover 90 preferably contains a very thin film (eg, on the order of 2500 angstroms or less). In practice, the total thickness of the protective cover 90 is preferably less than about 100 angstroms. A thickness in this range is preferred because it facilitates uniform and complete removal of the cover 90 when cleaning the covered surface of the substrate with the desired cleaning solution. As used herein, the terms "covered surface" and "covered substrate" refer to the surface and substrate in the presence of cover 90 (ie, before the cover is removed). Are shown respectively.

Cover 90 with a thickness greater than 100 angstroms is beneficial for a particular application. However, it has been found that such covers are not easily washed away. For example, thick covers have usually been found to require longer cleaning times. In addition, care must be taken to completely and uniformly remove such covers in the cleaning process. Furthermore, when a particularly thick cover is used, it is prone to form irregular surfaces that carry residues that are not removed from the cover 90 by cleaning. Such irregular surfaces have an undesired wavy or stained appearance. It also turned out to be difficult to determine when the entire cover 90 was washed away when using the exceptionally thick cover 90.

[0068] However, it should be noted that the thickness of the cover 90 may exceed the above preferred range. For example, it is not a necessary requirement that the thickness of the temporary protective cover 90 be an optically meaningless thickness. The cover 90 according to the invention should be removed. Therefore, the cover can be deposited to an optically meaningful thickness. However, in many cases it may be preferable to use a cover 90 that is not optically important. For example, it may be desirable to produce a glass sheet with a temporary protective cover 90 on both main surfaces (ie, the inner and outer surfaces). When incorporating a glass sheet into a multi-pane IG unit, the inner surface of the pane is exposed to the protective space between the panes (ie, the "space between the panes"), while the outer surface is exposed to the environment outside the IG unit. (Ie, the outer surface is not enclosed in the space between the panes). Therefore, it is desirable to provide flexibility to the protective cover 90 on the surface that is enclosed within the space between the panes of the IG unit. In these cases, the cover 90 present on the glass, of course, preferably does not alter the optical properties of the IG unit. It is not necessary to remove the cover 90 from these surfaces unless the surrounding surfaces of the IG unit are visually contaminated.

[0069] In most cases, the preferred thickness range for the protective cover 90 is less than about 100 angstroms. As mentioned above, the cover 90 is preferably removed when washed with a weak acid or a weak base. Therefore, no specific maximum thickness is required. However, the cover 90 should be thick enough to provide a protective measure against contamination by silicones and other environmental organics and residues. That is, the cover 90 is preferably thick and dense enough to prevent this type of contaminant from penetrating the cover 90 and contaminating the underlying surface. A protective cover 90 formed according to the present invention, the cover having a thickness of about 5-10 angstroms, is suitable for this purpose. However, a major advantage of the cover 90 according to the invention, namely contamination protection and expected uniform removal, is obtained at thicknesses of about 25 to about 60 angstroms, optimally about 25 to about 45 angstroms. It is thought that it will be possible.

[0070] The optimum thickness of a particular cover 90 depends on the type of substrate to which the cover is applied and the method of manufacture. For example, glass sheets are usually hardened in the manufacturing process. Quenching may be done to increase the mechanical hardness of the glass or to generate internal stresses in the glass, which causes the glass to not become dangerous and large pieces when the glass sheet breaks. It is crushed into small pieces. During quenching, the glass is subjected to high temperature treatment before being cooled at a controlled cooling rate. For example, hardened glass is generally heated to or near the melting point of the glass. More specifically, quenching temperatures on the order of 600 ° C are common. Further, the glass may be subjected to such a high temperature treatment for a long time (for example, a plurality of hours).

Unfortunately, the existing protective coatings mentioned above (eg, paper, plastics, polymers, etc.) cannot be expected to withstand the high temperatures of glass quenching. For example, the literature by Medwick et al. Discloses sputtered carbon-containing coatings that are clearly described as being burned out during quenching. On the other hand, it was found that the protective cover 90 according to the present invention sufficiently withstands quenching of glass. On the contrary, the cover 90 according to the invention would be ideal for application to glass that is then hardened (or another heat treated) after being coated. Certain protective covers 90, which have a thickness less than about 20 angstroms, have been found to be adversely affected by the glass quenching process. As described below, these covers will have less protection than desired after being subjected to the quenching process of the glass. Although no satisfactory explanation has been given for this phenomenon, it is considered to be due to the recrystallization and density change of the constituent materials of the cover 90 during the quenching process. Therefore, the desired thickness of the cover 90 according to the invention is at least about 20 angstroms, more preferably at least about 25 angstroms, if the cover is subjected to quenching or another heat treatment. A cover 90 with a thickness of several angstroms is considered to be sufficiently effective in protecting non-quenable substrates.

[0072] The temporary protective cover 90 may include a film made of any suitable material having the desired properties. As mentioned above, it is effective to form a protective cover 90 made of a material that is resistant to high temperatures on the order of about 600 ° C (eg, glass quenching temperature). In one embodiment, the cover material is stable in the presence of water at neutral pH, but disintegrates, dissolves, softens or deteriorates in the presence of a cleaning solution that is at least somewhat acidic or somewhat basic. It is a material. For example, the cover 90 may be formed from a material that disintegrates in the presence of loose acids or bases. In a preferred embodiment, the cover 90 is formed from a weak organic acid, for example a material that disintegrates in the presence of common household vinegar. The acidity of different vinegars may vary, but a typical household vinegar has a pH of about 3. Alternatively, the temporary cover 90 can be formed from a material that disintegrates in the presence of a weak base, such as a weak ammonia solution. For example, in one such embodiment, the cover 90 comprises a material that disintegrates in the presence of a common household ammonia solution (pH is about 11 to about 12.5).

The temporary cover 90 according to the invention can be formed from a material that disintegrates in the presence of either acidic or basic cleaning solution. Of course, the outer surface below the cover 90 is preferably formed from a material that is resistant to the desired cleaning solution. In most cases, the protective cover 90 is preferably formed from a material that is resistant to the industrial glass cleaning process, so the desired cleaning solution is generally at least somewhat acidic or basic cleaning solution.

The composition of the protective cover 90 is preferably chosen to complement the composition of the durable surface that holds the cover. More specifically, it is preferable to form the protective cover 90 from a material that disintegrates in the presence of a selected cleaning solution, which cleaning solution does not simultaneously disintegrate the surface beneath the cover or adversely affects the surface. Does not reach. For example, the cover 90 is preferably formed from a material that is completely and uniformly removed when cleaning with the cleaning solution of choice. In addition, it is preferred that the outer surface supporting the protective cover 90 and ultimately exposed by removal of the cover be resistant to the cleaning solution selected (ie, the coating is substantially in the presence of the cleaning solution). Does not disintegrate, does not dissolve, does not soften, or does not deteriorate). Therefore, it is advantageous to select the material of the cover 90 to supplement the properties of the surface for provisional protection. That is, the cover 90 is formed from a material that is selected to disintegrate when the underlying surface comes into contact with a resistant cleaning solution.

[0075] Therefore, if the cover 90 is held by a glass sheet, it is advantageous to form the cover 90 from a material that can withstand the rigors of conventional glassmaking. In such an embodiment, the cover 90 is preferably stable in the presence of hot water or conventional glass cleaners (eg, cleaners that may be present in industrial glass cleaners).

[0076] As described above, it is advantageous to form the temporary cover 90 from an inorganic material. For example, this aspect is preferred when the underlying surface exerts a photocatalytic effect. If the cover 90 is held by a photocatalytic surface, the cover 90 may deteriorate as a result of the resolution of the photocatalytic surface. Inorganic materials are generally considered to be resistant to photoactivity. Therefore, if the protective cover 90 is supported on a photocatalytic surface, it is particularly preferred to form the cover 90 from an inorganic material.

[0077] In one aspect of the present invention, the temporary protective cover 90 contains a metal oxide. As used herein, the term "metal" refers to metals and metalloids or metalloids. Metal oxides are effective for many reasons. For example, according to the aforementioned literature by Medwick et al., A carbon-containing coating is a functional layer on which the coating is deposited. Oxygen may be released from the layer) within the range in which oxygen remains in the layer. On the other hand, when the protective cover 90 made of metal oxide is used, since the metal oxide has already been oxidized, the occurrence of such a phenomenon cannot be expected. Metal oxides also have the desired degree of durability. In addition, metal oxides can generally be deposited by a variety of deposition methods. In a particularly preferred embodiment, the cover 90 contains one or more preferred metal oxides. These preferred metal oxides include oxides of metals selected from the group consisting of zinc, bismuth, cadmium, iron and nickel. Oxides of metals selected from these groups are stable in water but disintegrate in the presence of weak acids or bases and are easily removed by washing with a mildly acidic or loosely basic cleaning solution. .. These metal oxides exhibit sufficient protection when they have the desired thickness in the range described herein.

[0078] It has been found that zinc oxide is very suitable as a material for the temporary protective cover 90. Zinc oxide is particularly preferred for many reasons. For example, a zinc oxide cover with a thickness less than about 100 angstroms is effective in protecting the underlying surface from surface contamination. In practice, the zinc oxide protective cover 90 has been found to be effective in protecting surface contamination at thicknesses of about 20 angstroms or less. However, when the cover 90 is subjected to a glass quenching process, a thickness of at least about 25 angstroms is preferred. In addition, zinc oxide has been found to be particularly easily removed in a complete and uniform state when washed with a weak acid or weak base (eg, vinegar). Zinc oxide can be sputtered at a very high rate and can be deposited at a relatively low cost.

[0079] In one preferred embodiment, the temporary cover 90 comprises a zinc oxide sputtered film having a thickness of at least about 25 angstroms, more preferably about 25 to about 60 angstroms, preferably about 25 angstroms. ~ About 45 angstroms. As described below, the sputtered zinc oxide cover 90 having a thickness in such a range is particularly effective in protecting the substrate surface from contamination (eg, contamination when exposed to silicone) as well as being particularly effective. , Weak acid or weak base is surely removed in a complete and uniform state when applied. In addition, the zinc oxide cover thus exhibits resistance during the glass quenching process.

[0080] Therefore, it is desirable that the temporary cover 90 according to the present invention has some features. First, it has the ability to protect the surface from contamination, eg, contamination by silicone vapors or residues, when applied on a durable surface to a thickness that is easily removable. Second, the temporary cover with the thickness to be used collapses and is present underneath when subjected to a cleaning process with a desired cleaning solution (eg, at least a somewhat basic or somewhat acidic aqueous solution). It has the property of being removed relatively easily. The terms "disintegrated" or "disintegrated" as used herein indicate that the temporary cover 90 is actually removed during the cleaning process. The cover is not removed when the protective polymer film is mechanically peeled or torn from the surface to be protected. Rather, the temporary cover 90 disintegrates during the cleaning process by dissolving in the desired cleaning solution or at least softening or swelling in the cleaning solution. Preferably, virtually all covers 90 are removed during cleaning. Ideally, the cover 90 is completely removed from the underlying surface during the cleaning process. In addition, the durable surface is preferably not damaged by the cleaning treatment required to remove the protective cover 90.

[0081] In a preferred embodiment of the invention, the protective cover 90 comprises a film made of a sputtered material. The sputtered protective cover 90 has many advantages. For example, the cover can be deposited under controlled sputtering conditions so that it provides protection from contamination as soon as the coating substrate separates from the sputtering chamber. In addition, the thickness of the sputtered protective cover 90 can be adjusted with very high accuracy and uniformity, ensuring uniform protection of the substrate. Similarly, the protective cover 90, which is a desirable protective measure against contamination due to its substantially non-porous nature, can also be easily formed by sputtering. Surprisingly, the spatter cover 90 was found to effectively protect surface contamination even at small thicknesses such as 10 angstroms. However, it is preferable to impart a somewhat thicker (eg, at least 25 angstroms) cover 90 to the hardened substrate.

[0082] As described above, the cover 90 can be conveniently formed from a sputtered metal oxide film. The spatter metal oxide film can be deposited using various sputter deposition methods. One possible deposition method for this type of film is to sputter a target formed by the desired metal oxide itself in a non-reactive atmosphere, such as in argon. However, metal oxide targets cannot perform reliable sputtering like pure metal targets. This is because the conductivity of metal oxides is lower than that of the corresponding metals. Therefore, reliable sputtering of a metal oxide target in a DC sputtering apparatus is difficult. As a result, the metal oxide film is more commonly deposited by sputtering the metal target in an oxidizing atmosphere. For example, the zinc oxide protective film 90 has an oxidizing atmosphere (eg, about 8 × 10).^-3It can be deposited by sputtering the zinc target in (mbar oxygen).

[0083] Thus, in a particularly preferred embodiment, the protective cover 90 is formed by sputtering a metal target in an oxidizing atmosphere. As will be readily appreciated by those skilled in the art, the sputtering atmosphere can be varied to obtain the desired sputtering rate. For example, the sputtering atmosphere may consist of pure oxygen, but this is not a requirement. In fact, a mixture of oxygen and an inert gas increases the sputtering rate. Therefore, it would be advantageous to use a sputtering atmosphere containing oxygen and up to about 40% (preferably 0-20%) argon. As will be readily appreciated by those skilled in the art, the sputtering rate can be adjusted and the arcing can be reduced by varying the output applied to the sputtering target.

[0084] In one manufacturing apparatus that produces good results, a single planar metallic zinc target is used. This target is 100% O₂Is sputtered with a power of about 12 kW in a sputtering atmosphere containing the above. The glass passes through the sputtering target at a speed of about 300 inches / minute.

FIG. 3 shows another aspect of the invention, in which the substrate 10 has an outer coating 20 and a temporary protective cover 90 on one side 12 and a reflective coating 30 on the other side 14. .. The outer coating 20 of this embodiment may be any desired type of coating. For example, the external coating may be the preferred type of hydrophilic coating or photocatalytic coating described above, or any other coating that imparts the desired properties to the substrate. Further, the outer coating 20 is a desired requirement and may be omitted if desired.

As will be apparent to those skilled in the art, the reflective coating 30 can take any desired form depending on the desired properties. For example, when the coated article is used as a mirror, the reflective coating 30 may include one or more relatively thick reflective metal layers (in the illustrated embodiment, a particularly preferred multilayer coating 30). Show). A wide variety of reflective films are known in the art, and the detailed properties of this type of reflective coating 30 are outside the scope of the present invention.

A particularly preferred embodiment shown in FIG. 3 shows a particularly useful reflective coating 30 typified as an infrared reflective coating (eg, a coating commonly used as a low emissivity coating). Generally, these coatings have a metal layer sandwiched between a pair of dielectric layers (eg, metal oxides or metal nitrides). By repeating this structure, the infrared reflection characteristics of the film laminate may be further enhanced. An example of a useful infrared reflective film laminate is disclosed in US Pat. No. 5,302,449 by Eva et al., The entire description of which is also part of this specification.

The reflective coating 30 shown in FIG. 3 may include one or more layers of dielectric material. coat) 32 is included. For example, the basecoat 32 may include a zinc oxide layer having a thickness of about 150 to about 275 angstroms. The first metal layer 34 can be provided directly on top of the base coat 32. The metal layer may be, for example, a silver layer having a thickness of about 100 to about 150 angstroms. The second dielectric layer 38 can be provided on the first metal layer 34. The thickness of the dielectric layer 38 depends at least on whether or not the second metal layer 40 is included in the film laminate. As shown, in a film laminate with two metal layers, the second dielectric layer 38 generally contains a relatively thick metal oxide layer, eg, a zinc oxide layer of 700-750 angstroms. You may. Preferably, a relatively thin protective layer 36 is provided between the metal layer 34 and the dielectric layer 38. The protective layer serves to protect the metal layer 34 during the sputtering deposition process of the dielectric layer 38. The protective layer 36 may include, for example, a metallic titanium layer or a niobium layer having a thickness of 25 angstroms or less.

[0089] In the embodiment shown in FIG. 3, the second metal layer 40 is formed on the second dielectric layer 38. The second metal layer 40 is usually formed of the same material as the first metal layer 34. For example, the second metal layer 40 may contain about 125 to about 175 angstroms of silver. The second protective layer 42 (thickness: about 25 angstroms) formed of titanium, niobium, or the like is preferably formed on the metal layer 40. As mentioned above, the protective layer 42 protects the metal layer during the deposition process of the dielectric layers 44 and 46 located on it. The third dielectric layer 44 is formed on the protective layer 42. The dielectric layer 44 may be a layer of metal oxide or metal nitride, for example zinc oxide (thickness: about 250 to about 300 angstroms). In this case, an outer layer 46 made of a mechanically and / or chemically resistant protective material can be formed on the dielectric layer 44. In one preferred embodiment, the protective layer 46 is a Si having a thickness of about 50 to about 60 angstroms.₃N₄Includes film.

The reflective coating 30 on the inner surface 14 of the substrate 10 shown in FIG. 3 does not carry the protective cover 90. However, if desired, a protective cover 90 can be formed on the reflective coating 30. Therefore, in another aspect of the invention (not shown), a substrate 10 as shown in FIG. 3 having a protective cover 90 on a reflective coating 30 on the inner surface 14 of the substrate 10. included.

[0091] The substrate as shown in FIG. 3 is well suited for use in low emissivity articles. For example, a substrate having such properties is generally incorporated into a glass unit (IG unit) insulated by multiple panes. The IG unit is well known in the art and it is not considered necessary to elaborate on this, but it will be briefly described. IG units generally have two or more panes (eg, glass panes) spaced apart by spacers. The spacer 101 is generally formed from a hollow metal or plastic tube. The spacer 101 may optionally carry a desiccant 103 that communicates with the gas in the space 115 between the panes. Such desiccants are useful in removing the moisture that penetrates between the panes. Edge seal A barrier to gas and moisture may be formed by applying seal) 105 around the outer periphery of the spacer. For example, the edge seal 105 generally contains a silicone that outgasses over a long period of time, as described above. Such an edge seal 105 is in close proximity to the source of contamination for panes 10 and 100 of the insulating glass unit.

FIG. 4 shows an IG unit in which two spaced panes 10 and 100 have facing inner surfaces 14 and 114, between these surfaces, the space between the sealable panes. Limit 115. As in the case of low emissivity insulating glass units, one of the protective inner surfaces retains the infrared reflective coating 30. In the illustrated embodiment, the reflective coating 30 is retained on the inner surface 14 of the outer pane 10. In this embodiment, the outer surface 12 holds a durable outer coating 20 with a temporary protective cover 90. The durable coating 20 may be a hydrophilic coating, a photocatalytic coating, or any desired type of coating. Only one of the outer surfaces 12 and 112 of the illustrated IG unit holds the outer coating 20 and the protective cover 90, but optionally both of these surfaces 12 and 112 have the desired coating 20 and / or protective cover. 90 may be provided. For example, it is desirable to provide a protective cover 90 on the outer surface 112 of the inner pane 100, even when the surface 112 does not hold any coating.

[0093] In the embodiment shown in FIG. 5, the substrate 10 has a first coating 20 and a second coating 20 on its outer surface 12 and on its inner surface 14, respectively. If desired, both coatings 20 may be hydrophilic coatings. This embodiment is particularly desirable when both surfaces 12 and 14 of the substrate 10 are in periodic contact with water. This is the case, for example, when both surfaces are exposed to the outdoor environment. Alternatively, both of these coatings 20 may be photocatalytic coatings. Furthermore, one of these coatings 20 may be a hydrophilic coating and the other may be a photocatalytic coating.

[0094] In the embodiment shown in FIG. 5, both coatings 20 on the substrate 10 hold the temporary protective cover 90. Thus, if any covered surface is contaminated, the contaminated cover 90 is easily removed to reveal the original surface of the coating 20 that is present under the cover. However, if desired, one of the protective covers 90 on the substrate 10 as shown in FIG. 5 may be omitted. In such an embodiment (not shown), the protective cover 90 is provided on only one of the coatings 20.

[0095] In the embodiment shown in FIG. 2, the substrate 10 retains a durable outer coating 20 formed directly on its outer surface 12. However, as mentioned above, this is not a requirement. For example, the outer coating 20 can be deposited on one or more films of the type having any desired property pre-deposited on the outer surface 12 of the substrate 10. FIG. 6 shows an example of such an embodiment, in which the outer coating 20 is deposited on a pre-deposited low emissivity layer 80. The multilayer coating 70 thus obtained also has a protective cover 90. In this embodiment, the low emissivity first layer 80 is formed directly on the outer surface 12 of the substrate 10, and the second outer layer 20 is formed directly on the low emissivity first layer 80. The outer coating 20 in the illustrated embodiment may be any desired type of coating. However, in a particularly advantageous embodiment, the outer coating 20 is a hydrophilic coating. As fully discussed in U.S. Patent Application No. 09 / 868,543, such coated substrates are very effective for use as windshields in automobiles (the specification). The entire teachings of this document are also part of this specification).

[0096] It is desirable that the low emissivity first layer 80 includes a dielectric layer formed by a thermal decomposition action. This pyrolysis layer is preferably formed directly on the outer surface of the substrate 10. The pyrolysis layer can also be formed from any desired material that provides a coating that is sufficiently durable compared to flat uncoated glass and provides a commercially acceptable emissivity reduction. .. The low emissivity first layer 80 shown in the aspect of FIG. 6 is formed from a single material layer. However, the low emissivity first layer 80 may have the form of a film laminate having multiple layers. A wide variety of pyrolytic low emissivity coatings are well known in the art. Therefore, the detailed teachings regarding all pyrolysis coating methods and compositions are outside the scope of the disclosure of the present invention.

[0097] Coatings formed by numerous pyrolysis actions and their deposition methods have long been well known in the art and are described in published literature. One suitable pyrolyzable low-emission film is commercially available under the trade name "Energy Advantage" [Rebay Owens Ford of Toledo (Ohio, USA)]. Degraded tin oxide. The detailed coating by "Energy Advantage" products is not well known, but suitable layers are provided according to one of the well-known methods for pyrolytically coating tin oxide, for example. Is considered to be.

[0098] Many dopants are known in the art for increasing the conductivity (and thus improving the emissivity) of layers such as tin oxide that are pyrolyzed. , Fluorine is the most common dopant of this type. One method of forming a fluorine-doped pyrolyzed tin oxide coating is described in detail in US Pat. No. 5,698,262 by Sobayland et al., The entire teachings of which also form part of this specification. It is a thing. The reader may refer to a very detailed description of the patent specification for this type of coating, the description of which is briefly summarized here. Generally, tin oxide is applied by chemical vapor deposition (CVD). In this case, a uniform vaporized reactant stream is formed in combination with the selected reactant and the reactant stream is fed onto the hot glass substrate. The vaporization reactant flow reacts on the surface of the hot glass substrate to deposit fluorine-doped tin oxide. In the oxidizing atmosphere present on the surface of the hot glass, the organotin coating compound is thermally decomposed to form a tin oxide coating.

[0099] CVD pyrolysis deposition is generally carried out during the glass manufacturing process by the float glass method and is carried out in a float metal bath or lehr or in the transition region between the bath and rare. The glass substrate is generally supplied at a temperature of about 7500 ° F to about 15000 ° F. Such temperatures are common temperatures for glass at various stages in the manufacture of float glass.

The CVD reactant flow used by Sobayland et al. To deposit tin oxide contains an organotin-coated compound that evaporates and feeds at or near a predetermined site on the advancing glass ribbon surface. Is done. Suitable organic tin compounds include: dimethyltin dichloride, diethyl tin dichloride, dibutyl tin diacetate, tetramethyltin, methyl tin trichloride, triethyl tin chloride, trimethyl tin chloride, ethyl tin trichloride, propyl. Tin trichloride, isopropyl tin trichloride, sec-butyl tin trichloride, t-butyl tin trichloride, phenyl tin trichloride and carbetoxyethyl tin trichloride and any mixture thereof. According to Sobayland et al., Dimethyltin dichloride is preferred. The organotin compounds and optionally carrier gases, oxidants, stabilizers, hydrocarbons, inert gases and the like are subjected to evaporation treatment to form a gaseous organotin reactant stream.

[0101] According to Sobayland et al., Vaporized organotin compounds can be prepared by the methods described in any of the following US patent specifications, the entire teachings of these specifications are also herein. It forms part of: 3,852,098, 2,780,553, 4,351,861, 4,571,350, 3,970,037, 4,212,663 and 4,261,722. According to Sobayland et al., The vaporized organotin compound-containing reactant flow is by evaporating the compound in a thin film evaporator in which a blend gas is present, for example, as described in US Pat. No. 5,090,985. Prepared and the entire teachings of this specification are also part of this specification. This gaseous reactant stream, which generally contains an inert carrier gas (eg, helium, nitrogen, argon or any mixture thereof), optionally contains an oxidizing agent such as water or oxygen. The preferred carrier gas is said to be helium, nitrogen or a mixture thereof containing oxygen as an oxidizing agent. The obtained vaporized organotin compound-containing reactant flow is generally heated to about 250 ° F to about 450 ° F and then fed to the reaction zone on the surface of the heated glass substrate.

[0102] Gaseous hydrogen fluoride or hydrofluoric acid (HF as used herein refers to hydrogen fluoride or hydrofluoric acid) reacts with vaporized organotin compounds. Sobayland et al. Have prepared another HF-containing reactant stream, generally consisting of HF and a carrier (preferably water vapor). It is said that by adding water to the HF-containing reactant stream, the growth rate of fluorine-doped tin oxide deposits increases, but the emissivity of the coated glass decreases. The HF-containing reactant stream may further contain conventional auxiliaries such as helium, nitrogen, argon and any mixture thereof as well as oxidizing agents such as oxygen.

The HF-containing reactant stream and the organotin reactant stream are before the reactant stream is fed to the surface of the heated glass substrate on which the coating should be deposited (preferably at a location relatively close to the surface). React to. The HF-containing reactant stream can be prepared by evaporating the compound using any of the methods mentioned above in connection with the vaporization of the organotin compound, or by supplying HF as a gas. The reaction between the HF-containing vaporized reactant stream and the vaporized organotin compound-containing reactant stream is carried out by mixing these two gas streams before they are fed to the surface of the heated glass substrate. be able to. Alternatively, a liquid or solution HF-containing reactant stream is injected into the vaporized organotin compound-containing heated reactant stream to evaporate the fluorine-containing solution or liquid compound, followed by the vaporized organo. Reactants of tin compound and HF, water and oxygen are fed onto the surface of a heated glass substrate to react these reactants on the surface and a fluorine-doped tin oxide coating is applied onto the surface. Deposit.

Sobayland et al. Teach a mixture having the following composition as a typical gaseous reactant mixture fed to the surface of a heated glass substrate: about 10 to about 60 mol% oxygen, about 2 water. Mixtures containing ~ about 50 mol% and HF about 0.2 ~ about 2 mol%, most preferably mixtures containing about 30 ~ about 50 mol% oxygen, about 15 ~ about 35 mol% water and about 0.5 ~ about 1.5 mol% HF. .. The homogeneous gaseous reactant mixture also contains an organotin compound, the desired concentration of which is a function of the desired thickness of the tin oxide coating and the line velocity of the substrate. Therefore, according to Sobayland et al., A sufficient amount of the organotin compound is supplied into the gaseous reactant mixture to form a coating of the desired thickness at the desired line rate of the substrate. Under common commercial operating conditions, gaseous reactant mixtures generally contain from about 0.01 to about 8 mol% of organotin compounds.

Sobayland et al. Teach that it is desirable to form a layer of material that acts as a sodium diffusion barrier between the outer surface of the glass sheet and the fluorine-doped tin oxide coating. They find the following: That is, when the fluorine-doped tin oxide coating is formed on the glass with a sodium diffusion layer interposed therebetween, the coated glass product has a lower emissivity and a lower sheet resistance. And show lower cloudiness. The sodium diffusion layer is preferably formed from silicon dioxide. The silicon dioxide layer is preferably formed by a conventional CVD method.

[0106] In a preferred embodiment by Sobayland et al. (Incorporated as the thermal decomposition laminate 25 shown in FIG. 1), a thin film of tin oxide was first deposited on the outer surface of the heated glass substrate, and then a thin film of silicon dioxide was applied. By depositing on it, a tin oxide / silicon dioxide base layer structure is formed between the glass and the fluorine-doped tin oxide layer deposited thereafter. Sobayland et al. Show that the silicon dioxide film not only acts as a sodium diffusion barrier, but also works with the first undoped tin oxide film to help suppress pearl light in the resulting coated glassware. ing. The use of such an anti-iridescent layer is disclosed in US Pat. No. 4,377,613, the entire disclosure of which is also part of this specification.

As shown in FIG. 6, the outer coating 20 is not always necessary, but it is desirable to deposit it directly on the outer surface of the low emissivity first layer 80. As mentioned above, the outer coating 20 in this embodiment may include any desired type of coating. When the coating 20 is a hydrophilic coating, the preferred water ductile coating works particularly well in the context of the pyrolytically formed low emissivity first layer. In such cases, it is desirable that the hydrophilic coating be formed on the low emissivity first layer 80 by sputtering as described above. For example, the outer surface of the low emissivity first layer 80 is placed below one or more silicon targets present in the oxidizing sputtering atmosphere, and the target is sputtered onto the low emissivity first layer 80. Silicon dioxide can be deposited directly. As mentioned above, the exact operating conditions under which the hydrophilic coating 20 is formed can be varied as needed to adjust the deposition of the coating of the desired thickness. The thickness of the coating 20 can be on the same order as the hydrophilic coating 20 in the embodiment shown in FIG. For example, a preferred thickness is from about 15 to about 350 angstroms, more preferably from about 15 to about 150 angstroms, and optimally from about 20 to about 120 angstroms. Those skilled in the art given the teachings of the present invention as criteria can easily select and change suitable operating conditions for depositing the coating 20 in different thicknesses.

Alternatively, the outer surface 20 of the substrate 10 as shown in FIG. 6 may be a photocatalytic coating. In such cases, the photocatalytic 20 places the outer surface of the first low emissivity layer 80 below one or more titanium-containing targets as described above and places the targets under argon, oxygen or oxygen and argon. It can be deposited by sputtering in an atmosphere containing a mixture of.

[0109] In the embodiment shown in FIG. 6, the internal surface 14 of the substrate 10 does not hold the temporary protective cover 90. However, the inner surface 14 may optionally retain a protective cover. Thus, in another embodiment (not shown), the substrate 10 as shown in FIG. 6 has a first cover 90 and an uncoated inner surface held by a hydrophilic low emissivity coating 70 on its outer surface 12. Holds the second cover 90 formed on 14.

[0110] Further, the inner surface 14 of the substrate 10 shown in FIG. 6 is not coated. However, it is desirable to apply any type of coating 20 to the inner surface 14 of this type of substrate 10. For example, it is desirable to form a hydrophilic coating, a photocatalytic coating, or any other coating on the surface that imparts the desired properties to the substrate. The inner surface 14 may optionally or additionally carry a reflective coating 30, which may have any suitable form depending on the desired properties of the coated substrate. For example, the coating may be an infrared reflective coating 30 having the properties described above in relation to the embodiment shown in FIG. The infrared reflective coating may optionally carry its own protective cover. Substrate coated in this way results in particularly low emissivity, but visible transmission and reflectance may not be ideal for some applications.

[0111] If desired, the cover 90 according to the present invention can be directly coupled to a window frame, window sash, or the like. In contrast, traditional paper, plastic, and polymer protective coatings are not well suited for such bonding. For example, the peripheral area of the protective paper or protective plastic must be excised or otherwise removed before being attached to the window frame or the like. For example, it has been found that the protective paper or protective plastic deteriorates over time, potentially loosening the installation pane that holds the paper or plastic within the envelopment frame. On the other hand, the protective cover 90 according to the present invention does not bring about such a problem.

[0112] In the aspects of FIGS. 9 and 10, a window assembly having a window pane 10 is shown, the window pane for a cleaning solution of choice, eg, a loose acid or a loose base. It has an outer surface 12 that exhibits durability. The outer surface 12 carries a temporary protective cover 90 containing a sputtered film that can be easily removed by cleaning with a cleaning solution of choice. The cover 90 is of the type having the characteristics as described herein. Thus, in one embodiment, the cover 90 has a sputtered film that is stable in the presence of water but disintegrates in the presence of loose acids or bases.

[0113] The window assembly shown in FIGS. 9 and 10 includes a frame structure 50 (eg, window frame, window sash, etc.) to which the window pane 10 is fixed. The frame structure 50 shown is very basic and it is also possible to use a frame structure having any desired form, including a simple casing placed on the peripheral edge of the pane or IG unit. it can. The pane 10 is secured to the frame 50 by a bead of sealant 77 attached directly to the protective cover 90 on the pane. The bead of the sealant 77 is directly attached to the peripheral edge of the protective cover 90 on the first side, which edge is located on the peripheral area of the outer surface 12 of the pane. Therefore, the peripheral edge of the cover 90 does not need to be removed before installing the pane 10. Rather, the perimeter can be permanently attached to a sealant 77 that can be permanently attached to the frame 50. The sealant 77 is coupled to the frame 50 (or another structure or member secured to the frame) on the second side.

[0114] As best shown in FIG. 10, the covered substrate 10 can be mounted within the frame 50, and optionally the frame or other peripheral members can be finished (eg, painted). Once attached, the cover 90 can be removed from the central region C of the outer surface 12 of the pane. Therefore, the peripheral edge of the cover 90 can be left on the pane 10 and permanently bonded to the bead of the sealant 77. This aspect is advantageous because the protective cover 90 does not have to be the edge to be removed prior to mounting the pane 10.

[0115] The present invention extends to a number of novel substrate manufacturing methods. For example, in one method of the invention, a substrate having an inner surface 14 and an outer surface 12 that are generally opposed to each other is provided (these surfaces are generally the main surfaces of the substrate). The durable coating 20 is formed on the outer surface 12 of the substrate 10. As mentioned above, the durable coating 20 preferably contains a substance that is resistant to the cleaning solution of choice. In one embodiment, the coating 20 is formed from a substance that is resistant to the action of weak acids or bases. If desired, the coating 20 may be a hydrophilic coating. The hydrophilic coating 20 may be formed directly on the substrate, but this is not a requirement. In a particularly preferred embodiment, the hydrophilic coating 20 is formed on the substrate 10 by sputtering silicon dioxide. For example, the formation of this coating can be carried out by sputtering in an oxidizing atmosphere of the silicon target as described above. Alternatively, the coating 20 may be a photocatalytic coating that can be deposited by sputtering the titanium-containing target as described above. The temporary protective cover 90 can then be formed on the durable coating 20. The cover 90 preferably contains a material that disintegrates in the presence of a weak acid or weak base, as described above. In one embodiment, the cover 90 is formed from a material that is resistant to high temperatures on the order of 600 ° C. In a preferred embodiment, the cover 90 is formed on the outer coating 20 by sputtering an oxide of a metal (zinc is optimal) selected from the group consisting of bismuth, cadmium, iron, nickel and zinc.

[0116] In another aspect, the method further comprises the process of incorporating the covered substrate into the IG unit as described above. In yet another aspect, the method further includes the process of delivering the covered substrate to the customer. In yet another aspect, the method further comprises the process of installing the covered substrate within the window frame, which may then optionally be installed on the wall of the building. ..

[0117] The present invention is extended to a method for processing a substrate. For example, in one method, a substrate with an outer surface that is resistant to selected cleaning solutions (eg, loose acids or bases) is provided. The outer surface comprises a temporary protective cover 90, which preferably contains a sputter film that protects the outer surface from contamination and is easily removed from the outer surface by cleaning with a predetermined cleaning solution. Is. As mentioned above, the cleaning solution selected may be a loose acid or a loose base. For example, the cover 90 can be formed from a material that is removed by washing with household vinegar, for example, vinegar having a pH of generally about 3. The protective cover 90 can be removed from the outer surface when it is desired to expose the outer surface. The covered substrate is installed, for example, by the manufacturer, distributor, owner of the house or building of the IG unit or window, or the covered substrate at the final application site (eg, the wall of the building). Provided by the builder or contractor.

[0118] In the method of the invention, at least a portion of the cover 90 is removed by cleaning the covered outer surface of the substrate with a predetermined cleaning solution, thereby exposing at least a portion of the underlying surface. The process is included. Preferably, virtually all of the cover 90 is removed by this cleaning process. This cleaning process can be performed by any of the conventional cleaning methods. For example, the covered outer surface is covered with the desired cleaning solution (the cleaning solution may be a mildly acidic or loosely basic solution) in the same manner as an average homeowner cleaning a window. It can be moistened or washed with a towel or the like impregnated with the washing solution. Alternatively, the cover 90 can be removed by cleaning the covered outer surface with a conventional squeegee device that carries the desired cleaning solution.

This cleaning process can be performed when it is necessary to expose the underlying surface of the cover 90. For example, it is preferable not to remove the protective cover 90 until the substrate is transported from a manufacturing facility in a pollutant environment. As mentioned above, the substrate is exposed to various sources of contamination, even after leaving the manufacturing environment. For example, the panes assembled to the IG unit are typically exposed in close proximity to the silicone sealants commonly used during the assembly of the IG unit. In such cases, it is advantageous to leave the cover 90 on the substrate 10 until the substrate 10 is incorporated into the IG unit or other assembly. In practice, it is preferable to perform the cleaning process after the covered substrate has been delivered to the installation site or the final consumer (eg, homeowner). In some cases, cleaning may be performed after the substrate has been installed so that the covered outer surface is disposed towards the outdoor environment. In such cases, the cleaning process exposes the outer surface, which is exposed to periodic contact with water. It is more preferable that the cleaning process is not performed until the covered substrate is installed in the final position (for example, a window frame which may be mounted in the wall of the building if desired). It is best not to perform the cleaning process until either the finishing process on or around the substrate (eg, painting the surrounding frame) is complete. By removing the protective cover 90 at such a late stage, the covered outer surface is protected from contamination during the manufacturing, storage, transport, installation and finishing processes. Therefore, it is most preferable to remove the cover 90 from the substrate 10 by performing a cleaning treatment after all the installation work and the finishing treatment are completed.

[0120] As described above, it is desirable that the temporary protective cover 90 is formed by sputtering. Similarly, if one or both of the outer coating 20 and the infrared reflective coating 30 are present, these coatings are also preferably formed by sputtering. As mentioned above, certain aspects of the invention include substrates that hold the coating on both major surfaces (ie, inner and outer surfaces). In such an embodiment, both coatings (ie, internal and external coatings) are deposited by passing the coatings through the sputtering line using conventional sputtering equipment.

[0121] In one method according to the invention, the outer coating 20 and the protective cover 90 are sputtered onto the outer surface 12 of the substrate 10 before the infrared reflective coating 30 is sputtered onto the inner surface 14 of the substrate 10. Such sputtering can be performed by placing the outer surface 12 of the substrate 10 below one or more targets adapted to sputter the material of the desired outer coating 20. For example, if the outer coating 20 is a hydrophilic coating, such one or more targets may be silicon targets, as described above. Alternatively, if the outer coating is a photocatalytic coating, such one or more targets may be titanium-containing targets, as described above. Sputtering of one or more targets can then deposit the desired outer coating 20 on the outer surface 12 of the substrate 10. The outer surface of the outer coating 20 is then placed below one or more targets (eg, zinc targets) adapted to sputter the material of the desired protective cover 90 (eg, zinc oxide) (eg, zinc oxide). Transport to the subsequent sputtering chamber). The target is then sputtered, for example, in an oxidizing atmosphere to deposit the protective cover 90 on the outer surface of the outer coating 20. The internal surface 14 of the substrate 10 is then placed below one or more targets adapted to sputter one or more films of the infrared reflective coating 30. The target is then sputtered to deposit the infrared reflective coating 30 on the inner surface 14 of the substrate 10. Of course, the order of deposition may be reversed if desired. That is, if desired, the infrared reflective coating 30 can be deposited on the inner surface before the outer coating 20 and cover 90 are deposited on the outer surface 12.

[0122] FIG. 7 schematically shows a two-way sputtering chamber according to one aspect of the present invention. As mentioned above, magnetron sputtering chambers are well known in the art and are commercially available from many manufacturers. Therefore, a detailed description of the conventional magnetron sputtering chamber is outside the scope of the present invention. In FIG. 7, the substrate 10 to be coated is arranged on a plurality of support rollers 210. The support rollers 210 are spaced apart along the length direction of the sputtering chamber 200. The exact spacing of these rollers 210 can be varied for reasons detailed below, but the rollers should be placed at small intervals along at least the middle length of the sputtering chamber 200. Is desirable, which can increase the effective coating area from the lower target 260.

[0123] In the illustrated embodiment, the substrate 10 is arranged across the rollers horizontally, eg, moving from left to right. The inner surface 14 of the substrate 10 is arranged upward, while the outer surface 12 of the substrate is arranged downward and placed on the roller 210 (eg, direct supportive contact with the roller). .. Although such an arrangement is the most common arrangement, the relative orientation of the base pair 10 inside the sputtering chamber 200 may be reversed and the relative arrangements of the upper targets 220a and 220b and the lower target 260. May be reversed. Therefore, the indications "upper" and "lower" targets are for convenience only, and the relative orientation of these targets in the sputtering chamber can be easily reversed if desired.

[0124] The sputtering chamber 200 shown in FIG. 7 comprises two spaced upper sputtering targets 220a and 220b. These targets may be flat targets, but are shown as so-called rotary or cylindrical targets in the figure. These targets are generally arranged parallel to each other, and the plurality of horizontally extending anodes 230 are generally arranged parallel to these targets. As proposed in US Pat. No. 5,645,699 by Sieck, the intermediate anode 230 can also be placed between these two targets (the entire teachings of this specification are also part of this specification). It is made).

[0125] By using a gas distribution system, the sputtering gas is supplied into the chamber adjacent to the targets 220a and 220b. Various gas distribution systems are known in the art, but the distribution system generally simply comprises a pair of pipes 235 with multiple openings or nozzles spaced apart from the target. It may be.

[0126] In a magnetron sputtering chamber, it is common practice in the art to use a plurality of targets placed above the substrate. However, a peculiar point of the sputtering chamber 200 shown in FIG. 7 is the presence of the lower target 260. The lower target is effective in sputtering the outer coating 20 (eg, hydrophilic coating, photocatalytic coating, etc.) onto the outer surface 12 of the substrate 10 and then sputtering the protective cover 90 onto the outer coating 20. Can be used. As described below, the upper target deposits one or more films of the infrared reflective coating 30 (eg, a metal oxide film) on the inner surface 14 of the substrate 10 when the infrared reflective coating 30 is present. Can be used effectively.

[0127] FIG. 7 shows a sputtering chamber 200 with one lower target 260, which chamber 200 can optionally include two or more lower targets. As in the case of the upper targets 220a and 220b, the lower target 260 comprises at least one anode 270, preferably two anodes 270 arranged close enough to generate a stable plasma. The gas distribution pipe 235 disposed in close proximity to the upper targets 220a and 220b is undesirably distant from the lower target 260 and is sputtered by periodically introducing the substrate 10 into the sputtering chamber 200. The room is effectively divided into two separately functioning areas. Therefore, it is preferable to install a separate gas distribution pipe 275 arranged below the gas close to the lower target 260, which guarantees a stable gas supply to the plasma near the lower target 260. If desired, the lower pipe 275 and the upper pipe 235 may be part of the same gas distribution system (ie, a set of both pipes can be connected to a single gas source).

The properties of the gas supplied by the upper pipe 235 and the lower pipe 275 depend at least in part on the composition of the upper sputtering target 220 and the lower sputtering target 260. In conventional magnetron sputtering, the target functions as a cathode. As mentioned above, it is difficult to reliably sputter many common deposition materials, such as metal and metalloid oxides, due to the electrical insulating properties of these materials. As a result, in such cases it is preferable to sputter the target containing pure metal and / or metalloid. The material actually deposited is oxidized by containing oxygen in the gas supplied to the sputtering chamber.

[0129] The substrate 10 divides the sputtering chamber to some extent, but the gas introduced from any moving space in the chamber into one region of the chamber is not excluded by this. Therefore, it is preferable that the gas supplied by the lower pipe 275 does not adversely affect the sputtering of the upper targets 220a and 220b. Of course, similarly, it is preferred that the sputtering of the lower target 260 is not adversely affected by the presence of gas supplied through the upper pipe 235. For example, the use of such a two-way sputtering chamber 200 is not advantageous when depositing an oxide coating on one side of the glass and depositing an oxygen sensitive metal on the other side.

[0130] A single pass through the bidirectional sputtering chamber as shown in FIG. 7 deposits the first coating on the inner surface 14 of the substrate 10 and the second coating on the outer surface 12 of the substrate 10. Is more advantageous. For example, the first and second hydrophilic coatings 20 can be conveniently formed on the substrate 10 as shown in FIG. 5 by passing through the bidirectional sputtering chamber 200 once. This coating formation can be carried out by using the upper targets 220a and 220b and the lower targets 260 formed from silicon and sputtering these targets in an oxidizing atmosphere at substantially the same time (eg, simultaneously). Similarly, the first and second photocatalytic coatings 20 are conveniently deposited by sputtering the upper titanium-containing targets 220a and 220b and the lower titanium-containing target 260 in an oxidizing atmosphere in a similar manner. Can be done. The two-way sputtering chamber 200 can also be conveniently used when depositing the first and second protective covers 90 on a substrate as shown in FIG. This cover formation can be performed by using the upper targets 220a and 220b and the lower targets 260 formed from zinc and sputtering these targets in an oxidizing atmosphere at substantially the same time (eg, simultaneously). The oxidizing atmosphere in these methods can be generated by introducing oxygen or a mixture of oxygen and argon into the chamber through the upper pipe 235 and the lower pipe 275. In such a method, the mixture of gases introduced through the two pipe sets 235 and 275 should not adversely affect the deposition of the inner or outer coating.

The two-way sputtering chamber 200 as shown in FIG. 7 can also be used to deposit inner and outer coatings of different compositions. For example, such a chamber can be used to deposit one dielectric layer of hydrophilic coating 20 and infrared reflective coating 30 on substrate 10 as shown in FIG. Also, for example, this deposition method can be carried out using upper targets 220a and 220b formed from the desired metal (eg zinc) and lower targets formed from silicon. These targets can then be sputtered in an oxidizing atmosphere at substantially the same time (eg, at the same time). Therefore, in the step of passing through the chamber once, the metal oxide (for example, zinc oxide) of the infrared reflective layer 30 is deposited on the inner surface 14 of the substrate 10, and the hydrophilic coating (for example, silicon dioxide) 20 Can be deposited on the outer surface 12 of the substrate 10.

Similarly, the bidirectional sputtering chamber 200 is used to deposit one dielectric layer of the outer photocatalytic coating 20 and the inner infrared reflective coating 30 on the substrate 10 as shown in FIG. it can. For example, this deposition method can be performed with upper targets 220a and 220b formed from the desired metal (eg zinc) as well as titanium-containing lower targets, which are at substantially the same time in an oxidizing atmosphere. It can be sputtered (eg at the same time). Therefore, in the step of passing through the chamber once, the metal oxide (for example, zinc oxide) of the infrared reflective layer 30 is deposited on the inner surface 14 of the substrate 10, and the photocatalytic coating (for example, titanium oxide) 20 Can be deposited on the outer surface 12 of the substrate 10.

Alternatively, one dielectric layer of the protective cover 90 and the infrared reflective coating 30 can be deposited on the substrate 10 as shown in FIG. 3 by passing through the bidirectional sputtering chamber 200 once. it can. For example, this deposition method can be carried out by using upper targets 220a and 220b, respectively, and lower targets (eg, all targets may be zinc) formed from the desired metal. These targets can then be sputtered in an oxidizing atmosphere at substantially the same time (eg, at the same time). Therefore, in the step of passing through the chamber once, the metal oxide (for example, zinc oxide) of the infrared reflective layer 30 is deposited on the inner surface 14 of the substrate 10, and the metal oxide (for example, zinc oxide) is made. Protective cover 90 can be deposited on the outer surface 12 of the substrate 10.

The outer coating (eg, hydrophilic or photocatalytic coating 20 or protective cover 90) is a metal, even when the dielectric layer of the inner coating (eg, infrared reflective coating 30) contains nitrides and the like. Although it contains oxides, according to one aspect of the invention, such materials are formed by the introduction of metal oxides into the nitrides to be deposited or by the introduction of nitrides into the metal oxides. As long as any of the coatings is not adversely affected, it can be sputtered simultaneously inside the two-way sputtering chamber 200. Ideally, the coating layer to be deposited on the inner surface 14 is an oxide or partial oxide when the coating 20 or protective cover 90 deposited on the outer surface 12 is a metal oxide. This ensures that the mixture of gases introduced through the two pipe sets 235 and 275 does not adversely affect the deposition of any of these coatings.

[0135] In a conventional magnetron sputtering chamber, a relatively small substrate can be provided without the risk of the substrate falling between the rollers by significantly reducing the spacing between the rollers 210 used to support the substrate. It becomes possible to process on the line. This spacing can be increased to minimize roller interference when forming the coating on the outer surface of the substrate.

The safe maximum spacing needs to be determined individually for a given range of sizes of the substrate to be processed. However, the greater the distance between the rollers disposed in the path from the lower target 260 to the outer surface 12 of the substrate, the greater the amount of sputter material deposited on the substrate. Of course, the spacing of the rollers in other regions of the sputtering apparatus can be maintained at normal spacing. By easily removing a few rollers in the bidirectional sputtering chamber 200, the chamber is more generally operated from the illustrated form by covering only one side of the substrate and having closer roller spacing. It is desirable to be converted into the form to be. Rollers with smaller diameters can be manufactured without changing the spacing between the rollers. In order to maintain the transfer speed of the substrate along the support at the same speed, these small diameter rollers can be rotated faster, for example using a pair of gears with the desired gear ratio.

[0137] The roller 210 may have any conventional structure. The conventional roller is a hollow metal tube. If desired, the rollers may be stiffened, for example by filling with rigid foam. Good results have been found when using a cylindrical aluminum roller wrapped with "Kevlar"® (rope). "Kevlar" provides a surface with which the substrate is in direct contact.

[0138] For special applications, the two-way sputtering chamber 200 shown in FIG. 7 is sufficient to completely form the desired inner and outer coatings. In many cases, the sputtering chamber 200 forms part of a sputtering line that includes a series sputtering chamber. Each sputtering chamber in the line can include both an upper target and a lower target, but in the most common application, a film laminate formed on the upper surface of the substrate (eg, an infrared reflective film laminate). ) Is thicker and more complex (ie, includes a series of different layers with different compositions) compared to one or more coatings formed on the lower surface of the substrate. Thus, most chambers in the sputtering line can include conventional lower sputtering chambers that have only an upper target and no target located below the support. When the sputtering line includes both the lower sputtering chamber and the bidirectional sputtering chamber 200, the position of the bidirectional sputtering chamber along the sputtering line can be changed. For example, if an oxide-containing protective cover 90 or hydrophilic coating 20 is formed by sputtering a lower target 260 in an oxidizing atmosphere, a non-oxidizing layer (eg, low emissivity) is placed on the upper surface of the glass in the same room. Infrared reflective silver layers, such as those commonly used in low emissivity film laminates) should not be deposited. It is preferable to operate the chamber used for sputtering the pure metal layer as a lower sputtering chamber or an upper sputtering chamber, but it is preferable not to operate as a two-way sputtering chamber by omitting the lower target.

The two-way sputtering chamber 200, as shown in FIG. 7, is believed to minimize costs and maximize production efficiency when coating both sides of the substrate. Although less desirable, coatings on the inside of the substrate (eg, low emissivity film laminates) are formed in the first chamber pass, and coatings on the outside of the substrate (eg, hydrophilic or photocatalytic coatings and protective covers) All targets can be placed on the same side of the support in the sputtering chamber or sputtering line by forming on the second chamber pass and flipping the glass between the first and second chamber passes. It will be possible. However, this method is not as efficient as the method outlined above and may not be advantageous for low cost commercial substrate production.

[0140] As the substrate moves through the room, there will be times when the glass does not effectively shield the upper targets 200a and 200b from the lower target 260, or when the lower target does not effectively shield from the upper target. As a result, the material from the upper target is deposited on the lower target, and the material from the lower target is deposited on one or both of the upper targets. Ideally, a sputtering chamber 200 as shown in FIG. 7 with upper targets 220a and 220b and lower targets 260 having substantially the same composition is provided. For example, the upper targets 220a and 220b and the lower target 260 can all be zinc targets. In this case, by supplying oxygen or a mixture of oxygen and argon through the upper pipe 235 and the lower pipe 275, the zinc oxide cover 90 is formed on the outer surface 12 of the substrate 10 and at the same time the zinc oxide of the infrared reflective coating 30 is formed. A dielectric layer is deposited on the inner surface of the substrate 10. When the upper target has a different composition than the lower target, cross-contamination of the different targets may result in problems with sputtering or maintenance of constant product quality.

[0141] At least in theory, such a problem was such that the substrates were arranged to shield the upper and lower targets from each other by individually controlling the power delivered to each sputtering target. Only occasionally can this be resolved by ensuring that each target is sputtered. However, the power supply controller currently on the market does not have such a structure. Moreover, the control logic of such an arrangement becomes very difficult when using sputtering lines to coat substrates of different sizes rather than constant size.

FIG. 8 shows one of the sputtering chambers 300 that can be used to cover both the inner surface 14 and the outer surface 12 of the substrate 10 in a single chamber pass without substantial cross-contamination of the sputtering target. The aspect is shown. Components that have similar functions to the components shown in FIG. 7 are indicated by similar reference numbers (where 100 is added). For example, the upper gas distribution pipe 335 shown in FIG. 8 has a function similar to that of the upper gas distribution pipe 235 shown in FIG.

The sputtering chamber 300 shown in FIG. 8 is effectively divided into three coating regions by a pair of barriers 340. It is best to use a similar atmosphere in the three coating regions, as some of the gas in one coating region may flow into another coating region. However, the barrier 340 is a material sputtered within one coating region that effectively limits the amount of material that reaches the target within the other coating region.

[0144] In the embodiment shown in FIG. 8, each of the three coating regions 300a-300c is adapted to hold four targets, the two targets are placed above the substrate and the remaining two targets. Is placed below the substrate. Therefore, six upper target mounts 321 to 326 are arranged above the path of the substrate, and six lower target mounts 361 to 366 are arranged below the path of the substrate. When using this single multi-region sputtering chamber 300 to produce products with different properties, this embodiment provides maximum flexibility. FIG. 8 schematically shows each of the upper target mounts 321 to 326 arranged perpendicularly to each of the lower target mounts 361 to 366. However, the targets do not have to be arranged vertically as shown, and it is more effective to arrange them in a horizontal direction. In the embodiment shown in FIG. 8, the first coating region 300a is a downward sputtering region and has two upper targets (320a and 320b), but the lower target mount 361 or 362 does not have a lower target. ..

Sputtering gas should be supplied to the upper gas distribution pipe 335 and power should be supplied to the upper anode 330 in the first coating region, but gas to the lower gas distribution pipe 375. There is no need to supply power, and there is no need to supply power to the lower anode 370. A second coating region 300b upward sputtering region with two lower targets 360c and 360d, but upper target mounts 323 and 324 do not have a sputtering target. Similarly, the third coating region 300c has two lower targets 360c and 360f, but the upper target mounts 325 and 326 do not have a sputtering target.

The placement of the targets in the multi-region sputtering chamber 300 of FIG. 8 is merely exemplary, and for different products, the placement of the targets can be varied to maximize production efficiency. .. For example, if a thicker hydrophilic or photocatalytic coating 20 is required at the same substrate speed, a silicon or titanium-containing target is placed on each of the lower target mounts 361-366 and the upper target mounts 321-326. It is possible not to set a target in. If a thinner hydrophilic or photocatalytic coating 20 is sufficient (or to adequately reduce the speed of the substrate passing through the room), place the target only on the last two lower target mounts 325 and 326. At the same time, the sputtering targets can be installed on the first four upper target mounts 321 to 324. Of course, one or more coating regions 300a-300c are operated by placing targets on the upper and lower target mounts in the same region, as in the case of the two-way sputtering chamber 200 shown in FIG. be able to.

[0147] In the present application, the apparatus shown in FIGS. 7 and 8 and the deposition coating method using these coating systems form an infrared reflective coating 30 on one side of the substrate and on the other side of the substrate 10. The aspects of forming the hydrophilic or photocatalytic coating 20 and / or the protective cover 90 are described. However, such devices and methods can be used to form the desired coating on both sides of the substrate, regardless of the nature of the coating attached to the substrate. For example, this type of device has a protective cover 90 formed on one side 14 of the substrate 10 and a desired coating 20 (eg, hydrophilic coating, photocatalytic coating, or other type of coating) on the other side 12. ) Can be used to form.

The advantage of the system shown in FIGS. 7 and 8 is that the substrate 10 remains oriented in one direction (ie, the substrate does not need to be flipped, rotated, or otherwise subjected to coating). By passing the device once, it is possible to form sputtered coatings of the same or different composition on both sides 12 and 14 of the substrate 10. This allows the substrate to be moved along the production line using a simple set of standard transfer rollers. In the absence of application of the present invention, the substrate must generally be manually flipped over and transferred back in the coating apparatus in separate operating processes, or the substrate must be held and flipped at some point during the production process. A complex substrate manipulation system must be used. This makes it possible to produce a substrate having coatings on both sides particularly economically without compromising the quality of the coating.

[0149] Conventionally, when covering the bottom surface of a substrate, it has been considered that contact with a roller causes scratches on the coating and / or damage to the bottom surface of the substrate before formation of the coating. However, surprisingly, according to the present invention, it has been demonstrated that both sides of the substrate can be coated with excellent effect by a single pass.

The detailed operating conditions for forming the various coatings according to the present invention (eg, target composition, plasma composition, etc.) can be varied as needed to optimize the deposition of the desired coating. If the teaching content of the present invention is given as a standard, a person skilled in the art can select appropriate operating conditions for forming a predetermined coating according to the present invention without conducting undue experimentation.

The following non-limiting examples illustrate the effectiveness of the provisional cover 90 according to the invention with respect to the protection of the substrate from contamination. Comparative samples were prepared to accurately compare the hydrophilic surface holding the protective cover 90 according to the invention with a directly comparable hydrophilic surface not holding the cover 90. In Examples 1 to 3, two test samples (Sample A and Sample B) were prepared. Sample A contains a glass sheet holding a hydrophilic coating. Sample B comprises a glass sheet that retains the hydrophilic coating of Sample A and holds a protective cover 90 on the hydrophilic coating.

[0152] The glass sheet of sample A was prepared as follows. The clean surface of the soda-lime glass was coated by sputtering silicon dioxide in an oxidizing atmosphere containing 80% oxygen and 20% argon. Three rotating targets containing about 95% silicon and about 5% aluminum were operated with a power of about 100 kW, and the moving speed of the glass was about 300 inches / minute. The thickness of the resulting silicon dioxide coating was about 53 angstroms.

[0153] The glass sheet of sample B was prepared as follows. The clean surface of the soda-lime glass was coated by sputtering silicon dioxide as in sample B. The temporary protective cover 90 containing zinc oxide was then sputtered onto the silicon dioxide coating. Zinc oxide was sputtered from a planar zinc target in an oxidizing atmosphere containing 100% oxygen. The target was operated with an electric power of about 12 kW, and the moving speed of the glass was about 300 inches / minute. The thickness of the zinc oxide cover obtained was about 16 angstroms.

【0154】<u style="single">Example 1</u>The glass sheets of Sample A and Sample B were placed in the barrel adjacent to the glass processing device containing the uncured bulk silicone rubber material. After exposure to this environment for approximately 6 hours, the glass sheets of both samples were subjected to contamination testing. Two different tests were performed to assess the degree of contamination of the coated glass surface. In the first test, the contact angle of the coated glass surface was measured once or twice using a commercially available measuring instrument. Hydrophilic silicon dioxide coatings deposited under the conditions described above were expected to exhibit a contact angle well below 25 degrees to water before exposure to either environment. Also, zinc oxide coatings deposited under the conditions described above were expected to exhibit a contact angle of less than about 30 degrees with water before exposure to any environment.

In a second test, the ease of cleaning each sample was evaluated by spraying a commercially available glass cleaning solution "Windex"® onto the coated surface of each sample. .. The sprayed surface was manually wiped with a paper towel until the surface was cleaned to the extent that virtually no streaks were visible. Ease of cleaning (or "wiping ability") was evaluated on a scale of 1-5. The ease of cleaning ordinary uncoated glass before exposure to any environment is set to "3", the time when the glass surface can be cleaned very easily is set to "1", and the cleaning is practically more difficult. Was set to "5". Although this evaluation method is somewhat subjective, it provides an approximate qualitative measure of the ease of cleaning the glass surface. The coated surfaces of both samples were washed with common household vinegar. This treatment was performed by scrubbing the sample with a vinegar-moistened towel, usually as if cleaning the window. After washing with vinegar, the above test was repeated on both samples. The results of these tests are shown in Table 1 below.

[0156] [Table 1]<img file="JP3872011B2_D0001.tif" />After exposure to contamination, the coated surfaces of both samples exhibited greater contact angles than expected for the uncontaminated surface. The contact angle of the glass holding the protective cover 90 according to the present invention (Sample B) was somewhat smaller than that of the glass not holding the cover 90 (Sample A), but none of the samples showed a particularly desirable contact angle. Similarly, both Sample A and Sample B exhibited wiping properties that would not be particularly easily washed by the methods described above after exposure to contamination.

[0158] After subjecting to a wash treatment with vinegar, the following results were obtained for both samples. The silicon dioxide coating (Sample B) holding the protective cover 90 exhibited the desired hydrophilic surface properties expected for this type of uncontaminated silicon dioxide coating. The wiping property of this sample was improved from 2-3 to 1. This indicates that the sample is very easily washed. On the other hand, the wiping properties of the hydrophilic coating (Sample A), which does not retain the cover 90 when exposed to contamination, were not significantly affected by cleaning with vinegar. This is because the surface wiping property of this sample showed a moderate value of 3 before and after the cleaning treatment using vinegar. In addition, the contact angle of the sample with cover 90 ranged from 10 ° to 11 °, which was less than half the final contact angle of the sample without protective cover 90.

These results show that the hydrophilic surface properties of the desired silicon dioxide coating that retains the protective cover 90 according to the invention are this type of non-contamination coating, even after the covered surface is contaminated with silicone. It is shown that it is possible to return to the highly desirable hydrophilic state as expected. Furthermore, these results suggest that once the coating is directly exposed to silicone, attempts to clean this type of contaminant from the silicon dioxide coating in the above manner are highly inefficient. Further, it is expected that cleaning with various liquids cannot improve the wiping property or reduce the contact angle to the extent achieved by using the cover 90 according to the present invention.

【0160】<u style="single">Example 2</u>The glass sheets of Sample A and Sample B were installed in front of a large fan in the glass processing facility. After exposure to this environment for 6 hours, the glass sheets of both samples were subjected to the same contamination test as in Example 1. The test results are shown in Table 2 below.

[0161] [Table 2]<img file="JP3872011B2_D0002.tif" />[0162] After exposure to contamination, as in Example 1, both samples exhibited less desirable wipeability and contact angle than expected for this type of uncontaminated surface. After cleaning both samples with vinegar, the silicon dioxide coating (Sample B) holding the protective cover 90 showed better surface properties than Sample A not holding the cover 90. The wiping property of sample B was substantially improved from 3 to 4 to the desired value of 1. This indicates that the surface is very easy to clean. As in the above case, the sample (Sample A) that does not hold the cover 90 has a wiping property of 3 to 4 even after cleaning with vinegar and is not improved, and the wiping property of the sample is not improved by cleaning with vinegar. Has no obvious effect. In addition, the contact angles of the samples with cover 90 are reduced to 15 ° and 14 °, which is less than half of the values measured in some areas of sample A without protective cover 90. The value. These results support the effectiveness of the cover 90 according to the invention in protecting hydrophilic surfaces from contamination. Furthermore, these results show that these glass surfaces are surprisingly easily contaminated simply by blowing air on these samples with a fan in a typical glass processing facility.

【0163】<u style="single">Example 3</u>Silicone grease was applied to the central region of each glass sheet of Sample A and Sample B. After 6 hours, the silicone grease deposit was virtually wiped from the glass with a clean paper towel. Both samples were then subjected to contamination testing as in Examples 1 and 2. The results obtained are shown in Table 3 below.

[0164] [Table 3]<img file="JP3872011B2_D0003.tif" />Both samples after direct exposure to silicone grease showed well better contact angles than expected values for this type of uncontaminated surface. The contact angles of both samples varied depending on the area under test on the coated surface. Larger contact angles are generally measured in the vicinity of the central region of both sheets (ie, the area where the silicone grease is applied), and smaller contact angles are the peripheral area of the sheet (ie, the area where the silicone grease is directly applied). It was generally measured in the vicinity of the outer region of). The contact angle of the central region of both samples was about 105 °, and this value indicates that the region was highly contaminated. The wipeability of both samples was worse than ideal, especially in the central region of the glass, which was moderate 3 in both samples.

[0166] The test results of the sample after being subjected to the cleaning treatment using vinegar are as follows. The hydrophilic coating protected by cover 90 (Sample B) exhibited highly desirable surface properties. The wiping property of this sample improved from a non-characteristic value of 3 to a better value of 1, indicating that the surface of the sample was cleaned very easily. In addition, the contact angle of the sample after washing with vinegar was reduced from a very hydrophobic value (105 °) in some areas to a desirable hydrophilic value (12 °) on the entire surface. On the other hand, a good cleaning effect of vinegar was not observed for the hydrophilic coating (Sample A) that did not retain Copper 90. The wiping property of this sample before washing with vinegar was 2-3. The wipeability in some areas of this sample was improved by vinegar cleaning, but the wipeability in the central region of the glass was still moderate. Similarly, the contact angle of this sample was somewhat reduced, but the contact angle of the central region of the glass was still an undesired hydrophobic value (about 96 °). These results indicate that the cover 90 according to the invention effectively protects the glass surface from the contaminants, even when the silicone contaminants that are very difficult to remove are attached directly to the covered glass. Shown.

【0167】<u style="single">Example 4</u>A sample (sample C) containing a glass sheet holding a hydrophilic coating, another sample (sample C) containing a glass sheet holding the same hydrophilic coating as in sample C and having a protective cover 90 on the hydrophilic coating. Compared with D). The glass sheet of sample C was prepared as follows. Silicon dioxide was sputtered on a clean surface of soda-lime glass in an oxidizing atmosphere containing 80% oxygen and 20% argon. Three rotating targets containing about 95% silicon and about 5% aluminum were operated with a power of about 117 kw. In this case, the moving speed of the glass was set to about 300 inches / minute. The thickness of the silicon dioxide coating obtained was about 60 angstroms. The glass sheet of sample D was prepared as follows. Silicon dioxide was sputtered on a flat sheet of soda-lime glass in the same manner as in the case of sample C. The zinc oxide-containing temporary protective cover 90 according to the present invention was then sputtered onto the silicon dioxide coating. Zinc oxide was sputtered in an oxidizing atmosphere containing 100% oxygen. The planar zinc target was operated with an electric power of about 13 kW, and the moving speed of the glass was about 300 inches / minute. The thickness of the zinc oxide cover obtained was about 20 angstroms.

Prior to exposure to any of the environments, the glass sheets of Samples C and D were subjected to wipeability and contact angle tests in the same manner as in Examples 1-3. The results obtained are shown in Table 4A.

[Table 4]<img file="JP3872011B2_D0004.tif" />A plurality of sealed insulating glass units were assembled using the glass sheet of sample C. Similarly, an insulating glass unit was assembled using the glass sheet of sample D. An uncured silicone sealant was applied onto the pane of each unit opposite the pane holding the hydrophilic coating. These units were stacked vertically on conventional glass racks in the laboratory for multiple days.

[0169] The contact angle and wiping property of the first unit group including the sample C unit and the sample D unit were tested after 3 days. The results of these tests are shown in Table 4B below.

[Table 5]<img file="JP3872011B2_D0005.tif" />After exposure to contamination for 3 days, the surface properties of both samples were substantially undesired compared to the surface properties before exposure to contamination. The contact angles of both samples were more than three times the contact angles of the glass before exposure to contamination. Furthermore, the wiping properties of Sample C and Sample D changed from 1 to 2 and 1 to the undesired value (4), respectively. However, after cleaning with vinegar, the surface properties of the glass holding the cover 90 were significantly improved. The contact angle of this sample (Sample D) changed dramatically from 70 ° to 10 °. The wiping property of this sample was also significantly improved from 4 to 1, indicating that the sample was cleaned very easily. No similar effect was achieved by cleaning with vinegar on the surface properties of the sample without cover 90 (Sample C). After vinegar cleaning, the contact angle of this sample decreased somewhat, but its value was 52 °, which is still higher than what is preferred for hydrophilic coatings. .. Furthermore, the vinegar cleaning did not bring about a clear effect on the wiping property of the sample, and the wiping property was an undesired value (4) even after washing.

[0171] The wipeability test for the second unit group including the sample C unit and the sample D unit was performed after 5 days, and the wipeability test for the third unit group was performed after 19 days. The results of these tests are shown in Table 4C below.

[Table 6]<img file="JP3872011B2_D0006.tif" />After exposure to contamination for 5 or 19 days, the wiping properties of all samples were less desirable than the wiping properties before exposure to contamination. This indicates that these samples were contaminated. After cleaning with vinegar, the wiping property of the sample holding the cover 90 was substantially improved. For example, the wiping property of sample D in group 3 was dramatically improved from 4 to the highly desirable value (1). Conversely, vinegar cleaning had no apparent effect on the wiping properties of samples without cover 90. These results indicate that the cover 90 according to the invention is effective in protecting the glass surface from contamination, even when exposed to contamination for extended periods of time. Furthermore, the overall results of Examples 1-4 show that the protective cover 90 according to the invention effectively protects the glass from contamination, even on the order of 16-20 angstroms. However, as discussed below, it has been found that the thickness of the cover 90 according to the present invention should be at least about 25 angstroms when the cover is subjected to glass quenching.

【0173】<u style="single">Example 5</u>To protect the hardened glass from contamination, the comparative samples shown in Table 5A below were prepared to evaluate the effectiveness of the covers 90 according to the invention using the covers of different thicknesses.

[Table 7]<img file="JP3872011B2_D0007.tif" />[0174] Sample E was prepared as follows. Silicon dioxide was sputtered onto the clean surface of soda-lime glass. Silicon dioxide was sputtered in an oxidizing atmosphere containing 80% oxygen and 20% argon. Two rotating targets containing about 95% silicon and about 5% aluminum were operated with a power of about 27 kW, and the moving speed of the glass was about 260 inches / minute. The thickness of the silicon dioxide coating obtained was about 50 angstroms. Samples F to I were prepared as follows. The clean surface of the soda-lime glass was sputter coated with silicon dioxide as in sample E. The temporary protective cover 90 according to the invention containing zinc-tin oxide was then sputtered onto the silicon dioxide coating. Sputtering of zinc-tin oxide was performed in an oxidizing atmosphere containing 80% oxygen and 20% argon. The zinc-tin oxide covers of samples F to I operate planar zinc-tin targets (eg, zinc and less than 15% tin) with a power of approximately 6.8 kW, 13.7 kW, 20.5 kW and 27.3 kW, respectively. It was deposited by that. The thicknesses of the zinc-tin oxides of the obtained samples F to I were about 10 angstroms, 20 angstroms, 30 angstroms and 40 angstroms, respectively.

[0175] Sample J was prepared in the same manner as in Sample E. Silicon dioxide was sputtered onto the clean surface of a soda-lime glass sheet. Silicon dioxide was sputtered in an oxidizing atmosphere containing 80% oxygen and 20% argon. Two rotating targets containing about 95% silicon and about 5% aluminum were operated with a power of about 27 kW, and the moving speed of the glass was about 370 inches / minute. The thickness of the silicon dioxide coating obtained was about 35 angstroms. Samples K to N were prepared as follows. A silicon dioxide coating of Sample J was sputtered onto the clean surface of a soda-lime glass sheet. A temporary protective cover 90 according to the invention containing zinc-tin oxide was sputtered onto a silicon dioxide coating. Zinc-tin oxide was sputtered from a planar zinc-tin target (eg, zinc and less than 15% tin) in an oxidizing atmosphere containing 80% oxygen and 20% argon. The zinc-tin oxide covers of samples K-N were deposited by manipulating the targets with power of approximately 9.7 kW, 20 kW, 30 kW and 40 kW, respectively. The thicknesses of the zinc-tin oxide covers of the obtained samples K to N were about 10 angstroms, 20 angstroms, 30 angstroms and 40 angstroms, respectively.

Glass sheets of 10 samples were treated at conventional glass quenching temperatures (eg, temperatures on the order of about 600 ° C.). After quenching, the wiping property of each sample was measured. An uncured silicone sealant was applied directly to the central region of each glass sheet. After the silicone deposits were present on the sample for 3 days, the deposits were substantially removed by wiping the glass with a towel. Then, the wiping property of each sample was measured again. Finally, after washing each sample with vinegar, the wiping property was measured again. The results of these measurements are shown in Table 5B below.

[Table 8]<img file="JP3872011B2_D0008.tif" />After exposure to contamination, the wiping properties of 10 samples deteriorated from 1 to an undesired value (4). As expected, vinegar had little cleaning effect on the wiping properties of the samples without cover 90 (Samples E and J). Furthermore, the cleaning effect of vinegar on samples F, G, K and L was inferior. These samples carry a cover 90 with a thickness of 10 angstroms or 20 angstroms. For example, after washing with vinegar, samples F and G remained with local surface areas exhibiting moderate wiping properties (3). Similarly, sample K with a 10 angstrom cover showed undesirable wiping properties (3-4) after washing with vinegar, whereas sample L with a 20 angstrom cover had a wiping property of 2. In contrast, samples with a 30 angstrom or 40 angstrom cover showed constant wiping properties (1) after vinegar cleaning. These results indicate that the 10 angstrom and 20 angstrom covers 90 are undesirably affected by quenching. This effect may have been caused by the change in density due to the recrystallization of the oxide cover, which made the cover significantly porous. Therefore, in order for the cover 90 to withstand the glass quenching process, it is considered desirable to use a protective cover with a thickness of at least about 25 angstroms.

[0178] Although the preferred embodiments of the present invention have been described above, various modifications, modifications and modifications are made to these embodiments without departing from the scope of the technical idea and claims of the present invention. be able to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a substrate having a surface holding a temporary cover according to an aspect of the present invention.

FIG. 2 is a schematic cross-sectional view of a substrate having a coated surface holding a temporary cover according to another aspect of the present invention.

FIG. 3 is a schematic cross-sectional view of a substrate having two coated surfaces, one of which has a temporary cover according to yet another aspect of the present invention.

FIG. 4 is a schematic cross-sectional perspective view of a glass unit that is insulated and separated by multiple panes, wherein one coated surface of the pane holds a temporary cover according to still another aspect according to the present invention. ..

FIG. 5 is a schematic cross-sectional view of a substrate having two coated surfaces, each of which has a temporary cover according to another aspect of the present invention.

FIG. 6 is a schematic cross-sectional view of a substrate having a coated surface, wherein the coated surface holds a temporary cover according to still another aspect of the present invention.

FIG. 7 is a schematic configuration diagram of a two-way sputtering chamber for use in one method of the present invention.

FIG. 8 is a schematic schematic diagram of a multi-region / bidirectional sputtering chamber for use in another method of the present invention.

FIG. 9 is a partial schematic cross-sectional view of a window assembly according to another aspect of the present invention.

FIG. 10 is a partial schematic cross-sectional view of a window assembly according to yet another aspect of the present invention.

[Description of Code] 10 ... Base 20 ... Hydrophilic coating 30 ... Reflective coating 32 ... Base coat 34 ... First metal layer 38 ... Second dielectric layer 40 ... 2nd metal layer 44 ... 3rd metal layer 80 ... Low emission layer 90 ... Temporary protective cover 200 ... Sputtering chamber 210 ... Support rollers 220a, 220b ... Upper target 260 .. Lower target 235, 275 ... Gas distribution pipe 300 ... Sputtering chamber 321-326 ... Upper target mount 340 ... Barrier 361 ~ 366 ... Lower target mount