Heat treatable coated glass pane

Heat-treatable coated glass plate

[0001] The present invention relates to a method of manufacturing heat-treatable coated glass sheets with low emissivity (low-e) and/or solar control coatings. The invention also relates to the coated glass sheet produced by the method.

[0002] For a large number of applications (for example, for construction or automotive window glass), heat-treated glass sheets that are strengthened to impart safety properties and/or bent are required. It is known that for heat-strengthened and/or curved glass sheets, it is necessary to treat the glass sheets by heat treatment at a temperature close to or higher than the softening point of the glass used, and then rapid cooling to strengthen the glass sheet or by The glass plate is bent by the bending device. The relevant temperature range of standard float glass of soda-lime-silica type is generally about 580-690°C, and the glass plate is kept in this temperature range for several minutes before starting the actual strengthening and/or bending process.

[0003] In the following and in the claims, "heat-treated", "heat-treated", and "heat-treatable" refer to, for example, the above-mentioned thermal bending and/or strengthening process, as well as other thermal processes, during which other thermal processes are , The coated glass plate reaches a temperature in the range of about 580-690°C for a few minutes, for example, for up to about 10 minutes. If the coated glass sheet has no obvious damage after heat treatment (typical damage caused by heat treatment is high haze value, small holes or spots), then the coated glass sheet is considered heat-treatable.

[0004] It is worth noting that the parameter "haze" commonly mentioned when characterizing low emissivity and/or heat treatability of solar control coatings is often insufficient because it is not fully reflected in the coating of the coated glass plate. All types of defects that can occur during coating, heat treatment, processing and/or disposal. Some known heat-treatable coated glass plates exhibit significant and clearly visible changes in their optical properties and in particular their reflected color during heat treatment. It is also suitable to maintain the thermal properties of the plate during the heat treatment, and this can be characterized by maintaining a similar sheet resistance or, in some cases, obtaining a lower level of sheet resistance.

[0005] The low emissivity and/or solar control coating can be deposited by a physical vapor deposition (PVD) process, such as sputtering. Sputtered low emissivity and solar control coating stacks are usually composed of substrate/substrate dielectric layer sequence/(Ag/dielectric layer sequence)ⁿThe repeating sequence composition, wherein each n-dielectric layer sequence does not have to have the same thickness or composition. Due to the need for additional layers in the strengthenable coating and the potential tendency for triple silver solar control stacks, sputter coated stacks have become more complex in their properties. Therefore, n is equal to 2 or 3, which is more common in the industry. Because dielectric layers are generally thicker and slower to deposit than metal layers, a stack with a large number of such layers requires a large number of cathodes in equipment that produces coatings.

[0006] Previously, complex coating stacks had the required add-ons of coating equipment to obtain a sufficient number of cathodes to manufacture different materials in a sufficient number and sequence. In order to allow multiple reaction processes to proceed sequentially, additional pumping parts have to be included in the add-on. Doing so will have huge expenses and long interruptions, because the coating production line needs to be stopped for an extended period of time for engineering installation. Each new cathode and pumping part also requires supporting power supplies, vacuum pumps, conveyor parts, auxiliary devices, instruments and equipment, and is integrated into the control system. This may also lead to the restructuring of downstream logistics and possibly even new civil work or building expansion. As triple silver stacks (n=3) and even quadruple silver stacks (n=4) become more common, these problems may arise.

[0007] There have been some attempts to alleviate these problems in the prior art. WO 2012052749 A1 describes a method for producing coated glass, which includes depositing a chemical vapor deposition (CVD) coating on at least one surface of a glass substrate to produce CVD coated glass, and coating the glass on the CVD Sputter deposited another coating on the surface of the

The additional coating contains at least three reflective metal layers. The CVD primer layer is preferably a silicon oxide layer coated with a titanium oxide layer. However, the examples exhibited a high level of haze during the heat treatment, and exhibited a low level of visible light transmittance before and after the heat treatment (see page 7, Table 3).

[0008] WO 00/32530 A1 describes a method for producing heat-treatable low-emissivity coated glass, which includes the steps of: a) depositing a bottom layer on a glass substrate, and b) subsequently depositing reflections by a vacuum deposition method The sexual metal layer is characterized in that the bottom layer is deposited by a pyrolytic deposition process. The embodiment uses a silicon oxycarbide underlayer, and exhibits a visible light transmittance value from 73.2 to 76.3% before heat treatment (HT), and exhibits a visible light transmittance value from 74.9 to 78.2% after HT. The emissivity value of the embodiment is from 0.060 to 0.076 before HT, and from 0.065 to 0.072 after HT.

[0009] What is needed is to provide a method for manufacturing coated window glass that alleviates the above-mentioned problems and results in window glass that exhibits improved optical properties compared to prior art processes.

[0010] According to the first aspect of the present invention, there is provided a method of manufacturing a coated glass plate, which in turn includes the following steps:

[0011] a) Provide a glass substrate,

[0012] b) Using titanium tetraisopropoxide (TTIP) as a precursor, at least one CVD coating is deposited on the surface of the glass substrate by chemical vapor deposition (CVD), and

[0013] c) Depositing at least one PVD coating on the at least one CVD coating by physical vapor deposition (PVD).

[0014] Surprisingly, it was found that the use of TTIP as a precursor in the method of the present invention can produce coatings exhibiting improved optical properties both before and after heat treatment, compared to the plates obtained by the above-mentioned prior art process. board. In addition, the use of TTIP as a precursor provides a CVD coating that can be easily heat-treated, while if the deposition is based on titanium oxide (TiO_x) Layer, this will result in unacceptable haze at HT for plates with layers thicker than about 5nm. In addition, due to sufficient alkali barrier properties, the present invention can avoid the need to use a nitride-based layer as the base layer of the lower anti-reflection layer. This is advantageous because the deposition of the nitride layer requires a nitrogen atmosphere, and therefore the subsequent deposition of the oxide-based layer will require a longer coater to ensure gas separation. In addition, the use of TTIP as a precursor avoids the disadvantages associated with the direct deposition of chlorides (such as TiCl4) on the glass, which is also difficult, can lead to the formation of NaCl and therefore the formation of pinholes that can cause poor barrier properties.

[0015] The method of the present invention also has the benefit of allowing the base coating of the multilayer coating stack to be manufactured by CVD rather than PVD, which reduces the number of cathodes required. Therefore, the present invention avoids the need for at least most of the cathodes associated with lower dielectric layers used in low emissivity and/or solar control coatings. This frees up the cathode for use in depositing other layers at a higher rate or adding additional layers to the stack to increase its complexity.

[0016] In the following discussion of the present invention, unless stated to the contrary, the disclosure of alternative values indicating that one of the values is more highly preferred than the other value indicates the upper limit or the lower limit of the allowed range of the combined parameter should be considered To make an implicit statement: each intermediate value of the parameter between the more preferred and the less preferred alternative is itself relative to the less preferred value and also relative to the less preferred value. Each value between the value and the intermediate value is preferred.

[0017] In the context of the present invention, when it is said that a layer is "based on" a particular material or materials, this means that the layer is mainly composed of the corresponding material or materials, which usually It means that it contains at least 50 atomic% of the material or materials.

[0018] The CVD coating is preferably deposited in the presence of one or more oxygen-containing species. Preferably, the one or more oxygen-containing substances include one or more of organic oxygen-containing compounds, water or gaseous oxygen. Preferably, the organic oxygen-containing compound is an alcohol or a carbonyl compound (for example, an ester). Particularly good results have been obtained with esters with β-hydrogen-bearing alkyl groups. With

The alkyl group of β-hydrogen will preferably contain two to ten carbon atoms. Such compounds are preferred because larger molecules tend to be less volatile and therefore less convenient for use in the deposition of the CVD coating. Preferably the ester is ethyl formate, ethyl acetate, ethyl propionate, isopropyl formate, isopropyl acetate, n-butyl acetate and/or tert-butyl acetate.

[0019] Preferably, the deposition of the CVD coating includes the preparation of a precursor gas mixture, which may include TTIP and an oxygen-containing substance. The precursor gas mixture may further include a carrier gas or diluent, such as nitrogen, air, and/or helium.

[0020] Preferably the CVD coating has a thickness of at least 5nm, more preferably at least 10nm, even more preferably at least 20nm, most preferably at least 25nm, but preferably at most 60nm, more preferably at most 50nm, even more preferably at most 40nm, most preferably at most 30nm .

[0021] Preferably the CVD coating comprises at least one layer based on titanium oxide (TiOx) (doped or undoped). In some embodiments, x can be from 1.5 to 2.0. The titanium oxide-based layer may preferably have a thickness of at least 5nm, more preferably at least 10nm, even more preferably at least 20nm, most preferably at least 25nm, but preferably at most 60nm, more preferably at most 50nm, even more preferably at most 40nm, most preferably at most 30nm thickness. Among other uses, this layer serves as a glass-side diffusion barrier.

[0022] Preferably, TTIP is used as a precursor to deposit the at least one titanium oxide-based layer. Preferably, at least one titanium oxide-based layer deposited using TTIP as a precursor is arranged in direct contact with the PVD coating.

[0023] The CVD coating may further comprise at least one layer not based on titanium oxide. The CVD coating may further comprise at least one layer based on silicon oxide (such as silicon oxycarbide, silicon oxide or silicon oxynitride), tin oxide (doped or undoped), zinc oxide Substances (doped or undoped) or any mixture of these materials.

[0024] In some preferred embodiments, the CVD coating comprises at least one layer, wherein each of the at least one layer is based on titanium oxide (TiOx).

[0025] Preferably the main surface of the CVD coating furthest from the glass substrate has an arithmetic mean surface height of at most 3 nm, more preferably at most 2 nm, even more preferably at most 1 nm, even more preferably at most 0.7 nm, most preferably at most 0.5 nm Value Sa. The main surface of the CVD coating may have a Sa° of at least 0.3 nm. Sa gives an indication of surface roughness. A smoother CVD coating can facilitate the deposition of a smoother PVD coating and is considered advantageous because the resulting coated plate exhibits less absorption and lower sheet resistance (Rs).

[0026] It is particularly beneficial if the CVD coating is deposited during the glass production process. If the glass substrate contains a float glass substrate, the CVD coating will be conveniently deposited during the float glass deposition process in the float bath, in the annealing furnace, or in the gap of the annealing furnace. The CVD coating method is any chemical vapor deposition technique, especially atmospheric pressure chemical vapor deposition (for example, as in-line CVD performed during the float glass deposition process).

[0027] Preferably, the CVD coating is deposited on the glass substrate when the glass substrate is at a temperature ranging from 450°C to 800°C, more preferably when the glass substrate is at a temperature ranging from 550°C to 700°C. Depositing the CVD coating when the glass substrate is at these preferred temperatures provides higher crystallinity of the coating, which can improve toughenability (resistance to HT).

[0028] Preferably during the float glass production process, the CVD coating is deposited on the glass ribbon at substantially atmospheric pressure. Alternatively, the CVD coating can be deposited by low-pressure CV D or ultra-high vacuum CV D. Aerosol-assisted CVD or direct liquid injection CVD can be used to deposit the CVD coating.

[0029] In addition, microwave plasma-assisted CVD, plasma-enhanced CVD, remote plasma-enhanced CVD, atomic layer CVD, combustion CVD (flame pyrolysis), hot filament CVD, metal organic CVD, rapid thermal CVD, vapor phase epitaxy can be used Or photo-initiated CVD to deposit the CVD coating. After depositing the CVD coating (and before depositing other coatings), the glass ribbon is usually cut into pieces for storage or facilitating transfer from the float glass production facility to the vacuum deposition facility.

[0030] Preferably, the surface of the glass substrate on which the CVD coating is deposited is a gas side surface. Coated glass manufacturers usually

It is preferable to deposit a coating on the gas side surface (opposite to the tin side surface of the float glass) because deposition on the gas side surface can improve the properties of the coating.

[0031] The PVD coating is preferably deposited by sputter deposition. It is particularly preferred if the PVD coating is applied by magnetron cathode sputtering (whether in direct current mode, in pulsed mode, in intermediate frequency or radio frequency mode, or in any other suitable mode), so that the PVD coating is applied in a suitable sputtering mode. A metal target or a semiconductor target is sputtered reactively or non-reactively in a shooting atmosphere. Depending on the material to be sputtered, a flat target or a rotating tubular target can be used. The coating process is preferably carried out by setting suitable coating conditions so that any oxygen (or nitrogen) deficiency of any oxide (or nitride) layer of any anti-reflection layer of the coating is kept low, so that during the heat treatment In the process, the visible light transmittance and high color stability of the coated glass plate are obtained. Generally, the reference includes a coated glass plate of an uncoated 4mm thick standard float glass plate with a light transmittance T1 of 89% to specify the light transmittance value mentioned in this application document.

[0032] Preferably the PVD coating contains at least one reflective metal-based functional layer. Preferably, the functional layer is a silver-based functional layer.

[0033] Preferably, the coated sheet further comprises a lower anti-reflection layer located between the glass substrate and the at least one functional layer. The functional layer closest to the glass substrate can be directly deposited on the CVD coating, that is, the CVD coating optically acts as the lower anti-reflection layer or the first dielectric. Alternatively, the PV D coating may preferably further comprise at least one layer based on a dielectric material deposited between the CVD coating and the at least one functional layer.

[0034] Preferably, the PVD coating further comprises an upper anti-reflection layer on the functional layer.

[0035] In some embodiments, the board includes more than one functional layer. For example, the board may contain two, three or more functional layers. When the board contains more than one functional layer, each functional layer may be separated from the adjacent functional layer by an intermediate anti-reflection layer. By providing more than one functional layer, the functional layer can be separated by an intervening dielectric layer (=intermediate anti-reflection layer).

[0036] The PVD coating may further comprise at least one layer based on doped or undoped NiCr, Ti, Zn, Zr, Sn, Nb, ITO, TiOx, ZnxSnyOz, ZnO, SnOx, ZnxAlxOz , A1Nx, SiNx, SixAlyNz or mixtures thereof. Usually each functional layer is deposited between such layers.

[0037] The lower anti-reflection layer of the coating including at least one functional layer may include at least one combination of one or more of the following layers:

[0038] A base layer based on titanium oxide, silicon oxide (such as silicon oxycarbide, silicon oxide or silicon oxynitride), tin oxide (doped or undoped), zinc oxide ( Doped or undoped) or a mixture of any of these materials; [0039] a layer based on metal oxides such as Zn and Sn oxides and/or Sn oxides;

[0040] A separation layer based on metal oxide and/or Si (oxy)nitride and/or Al (oxy)nitride and/or alloys thereof; and

[0041] The top layer, which is based on Zn oxide.

[0042] In the order of leaving the glass substrate, it is preferable that the lower anti-reflection layer comprises at least:

[0043]. The base layer, the base layer is based on titanium oxide, silicon oxide (such as silicon oxycarbide, silicon oxide or silicon oxynitride), tin oxide (doped or undoped), zinc oxide (doped Or undoped) or any mixture of these materials; [0044]. Layers based on metal oxides such as Zn and Sn oxides and/or Sn oxides; and

[0045]. Top layer based on Zn oxide.

[0046] The lower reflective layer may be composed of three layers in order as described above.

[0047] In some embodiments, in order to leave the glass substrate, the lower anti-reflection layer comprises:

[0048] ο A base layer based on titanium oxide, silicon oxide (such as silicon oxycarbide, silicon oxide or silicon oxynitride), tin oxide (doped or undoped), zinc oxide (Doped or undoped) or a mixture of any of these materials; [0049] ο a layer based on metal oxides such as Zn and Sn oxides and/or Sn oxides;

[0050] ο a separation layer, the separation layer based on metal oxide and/or Si (oxy)nitride and/or Al (oxy)nitride and/or alloys thereof; and

[0051] o A top layer based on Zn oxide.

[0052] The lower anti-reflection layer based on metal oxides, such as Zn and Sn oxides and/or Sn oxides, is used to improve by providing a dense and thermally stable layer and promoting the reduction of the haze after heat treatment. Stability during heat treatment. The lower anti-reflection layer based on metal oxides such as Zn and Sn oxide and/or Sn oxide layer may have at least 0.5 nm, preferably from 0.5 to 10 nm, more preferably from 0.5 to 9 nm, even more preferably from 1 To 8 nm, even more preferably from 1 to 7 nm, even more preferably from 2 to 6 nm, even more preferably from 3 to 6 nm, most preferably from 3 to 5 nm. Due to the optical interference conditions, and due to the resulting decrease in the thickness of the base layer required to maintain the optical interference boundary conditions for the functional layer antireflection, the heat treatability decreases, the preferred upper limit of the thickness is 8 nm.

[0053] The lower anti-reflection layer based on a metal oxide, such as an oxide of Zn and Sn and/or an oxide of Sn, may be directly on the base layer.

[0054] The lower anti-reflection layer based on Zn and Sn oxide (ZnSnOx) layer preferably contains about 10-90wt.% of Zn and 90-10wt.% of its total metal content in wt.% Sn, more preferably about 40-60 wt.% Zn and about 4060 wt.% Sn, preferably Zn and Sn are each about 50 wt. %. In some preferred embodiments, the Zn and Sn oxide-based layer of the lower anti-reflection layer may contain up to 18wt.% Sn, more preferably up to 15wt.% Sn, even more preferably up to 10wt.% Sn . The oxide-based layer of Zn and Sn can be deposited by reactive sputtering of a mixed ZnSn target in the presence of O2.

[0055] The separation layer based on metal oxides and/or silicon (oxy)nitrides and/or aluminum (oxy)nitrides and/or alloys thereof may have at least 0.5 nm, preferably from 0.5 to 6 nm, more preferably The thickness is from 0.5 to 5 nm, even more preferably from 0.5 to 4 nm, most preferably from 0.5 to 3 nm. These preferred thicknesses make it possible to further improve the haze at the time of heat treatment. The spacer layer provides protection during the deposition process and during subsequent heat treatment. The separation layer is either substantially completely oxidized immediately after its deposition, or oxidized to a substantially completely oxidized layer during the deposition of the subsequent oxide layer.

[0056] The separation layer can be deposited by non-reactive sputtering using a ceramic target based on, for example, slightly substoichiometric titanium oxide (such as a TiO1.98 target) as a substantially stoichiometric or As a slightly substoichiometric oxide; by reactive sputtering of a Ti-based target in the presence of 02; or by depositing a thin layer of Ti-based and then oxidizing it. In the context of the present invention, "substantially stoichiometric oxide" means at least 95% but at most 105% stoichiometric oxide, and "slightly substoichiometric oxide" means at least 95% but less than 100% Stoichiometric oxide.

[0057] When the separation layer is based on a metal oxide, the separation layer may include a layer based on an oxide of Ti, NiCr, InSn, Zr, Al, and/or Si.

[0058] The term "(oxy)nitride of Si" includes silicon nitride (SiN_x) And silicon oxynitride (SiOxNy), and the term "Al (oxy)nitride" includes aluminum nitride (AlN_x) And aluminum oxynitride (AlOxNy). The layers of silicon nitride, silicon oxynitride, aluminum nitride, aluminum oxynitride are preferably substantially stoichiometric (for example, silicon nitride = Si3N4, x=1.33), but can also be substoichiometric or even superchemical Metered, as long as the heat treatability of the coating is not negatively affected thereby. A preferred composition of this type of layer is a substantially stoichiometric mixed nitride Si90Al10Nx.

[0059] Si (oxy)nitride and/or Al (oxy)nitride and/or alloys thereof can be reactively sputtered from Si-based targets and/or Al-based targets in a sputtering atmosphere containing nitrogen and chlorine, respectivelyLayer. The layer. The oxygen content of the layer based on Si-based (oxy)nitride and/or Al-based (oxy)nitride and/or its alloys can be derived from residual oxygen in the sputtering atmosphere, or derived from the controlled atmosphere in said atmosphere The amount of added oxygen. It is generally preferred if the oxygen content of the silicon (oxy)nitride and/or aluminum (oxy)nitride is significantly lower than its nitrogen content, ie if the O/N atomic ratio in the layer remains significantly below one. Most preferably, silicon nitride and/or aluminum nitride with negligible oxygen content is used. This feature can be controlled by ensuring that the refractive index of the layer is not significantly different from the refractive index of the oxygen-free silicon nitride and/or aluminum nitride layer.

[0060] It is within the scope of the present invention to use mixed Si and/or Al targets or to add metals or semiconductors to the Si and/or Al components of this layer in other ways. It is well-known and established to mix Al and Si targets, and other mixed targets are not excluded. The additional component can generally be present in an amount up to about 10-15 wt.%. Al is generally present in an amount of about 10 wt.% in a mixed Si target.

[0061] In addition to the metal oxide and/or silicon (oxy)nitride and/or aluminum (oxy)nitride and/or alloys thereof on which the separation layer is based, the separation layer may also include one or more Other chemical elements are used as dopants or alloys, for example, the one or more other chemical elements are selected from at least one of the following elements: Ti, V, Mn, Co, Cu, Zn, Zr, Hf , Al, Nb, Ni, Cr, Mo, Ta, Si, or an alloy selected from at least one of these materials.

[0062] The top layer of the Zn-based oxide mainly serves as a growth promoting layer for the subsequent deposition of the functional layer. The top layer of the Zn-based oxide is optionally mixed with metals such as Al or Sn in an amount of up to about 10 wt.% (wt.% based on the target metal content). The typical content of the metal such as Al or Sn is about 2 wt.%, and Al is actually preferred. It has been confirmed that Zn O and mixed Zn oxide are very effective as a growth promoting layer, which helps to obtain a low sheet resistance at a given thickness of the functional layer deposited later. If the top layer of the lower anti-reflection layer is reactively sputtered by a Zn target in the presence of 02, or if it is sputtered by a ceramic target (such as Deposition based on ZnO:Al) is preferred. The Zn-based oxide-based top layer may have a thickness of at least 2 nm, preferably from 2 to 15 nm, more preferably from 4 to 12 nm, even more preferably from 5 to 10 nm, even more preferably from 5 to 9 nm.

[0063] As is usual in the field of low emissivity and/or solar control coatings, the one (or more) silver-based functional layers may consist essentially of silver without any additives. However, it is also within the scope of the present invention to change the properties of the one (or more) silver-based functional layers by adding dopants, alloy additives, or even adding a very thin metal or metal compound layer, as long as the one (or The necessary properties of the silver-based functional layer as one (or more) infrared reflective layers with high light transmission and low light absorption are not significantly impaired thereby.

[0064] The thickness of the silver-based functional layer is determined by its technical purpose. For typical low emissivity and/or solar control purposes, the preferred layer thickness of a single silver-based layer is from 5 to 20 nm, more preferably from 5 to 15 nm, even more preferably from 5 to 12 nm, even more preferably from 7 to 11 nm, most preferably It is preferably from 8 to 10 nm. For a single silver coating, with such a layer thickness, a light transmittance value higher than 86% and a normal emissivity lower than 0.05 can be easily obtained after heat treatment. If better solar control properties are intended, the thickness of the silver-based functional layer can be appropriately increased, or several spaced functional layers can be provided.

[0065] When the plate includes two silver-based functional layers, the silver-based functional layer located farthest from the glass substrate may preferably have from 5 to 25 nm, more preferably from 10 to 21 nm, even more preferably from 13 to 19 nm, or even The thickness is more preferably from 14 to 18 nm, most preferably from 15 to 17 nm.

[0066] When the plate includes three silver-based functional layers, the two silver-based functional layers located farthest from the glass substrate may each independently preferably have from 5 to 25 nm, more preferably from 10 to 21 nm, and even more preferably The thickness is from 13 to 19 nm, even more preferably from 14 to 18 nm, most preferably from 15 to 17 nm.

[0067] Preferably, the top layer of the Zn-based oxide in the lower anti-reflection layer is in direct contact with the functional layer.

[0068] The one (or more) intermediate anti-reflection layer may comprise at least one combination of one or more of the following layers: a layer based on Zn oxide and/or Ti oxide;

[0069] NiCr-based oxide layer;

[0070] A layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn; and

[0071] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or Al, Si, Ti, and/or Zr oxide layers.

[0072] In some preferred embodiments, each functional layer is separated from adjacent functional layers by an intermediate anti-reflection layer, [0073] wherein each intermediate anti-reflection layer contains at least:

[0074] In order from the functional layer of the plurality of functional layers with the middle anti-reflection layer in between, which is located closest to the glass substrate, outwards,

[0075] A barrier layer based on Zn oxide;

[0076] A layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn;

[0077] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or Al, Si, Ti and/or Zr oxide layers, and

[0078] Zn-based oxide top layer.

[0079] In some other preferred embodiments, each functional layer is separated from adjacent functional layers by an intermediate anti-reflection layer,

[0080] wherein each intermediate anti-reflection layer includes at least:

[0081] In order from the functional layer of the plurality of functional layers with the middle anti-reflection layer in between, which is located closest to the glass substrate, outwards,

[0082] A barrier layer based on NiCr oxide;

[0083] A barrier layer based on Zn oxide;

[0084] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or Al, Si, Ti and/or Zr oxide layers,

[0085] A layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn; and

[0086] Zn-based oxide top layer.

[0087] The NiCr-based oxide layer may preferably have at least 0.3nm, more preferably at least 0.4nm, even more preferably at least 0.5nm, most preferably at least 0.6nm; but preferably at most 5nm, more preferably at most 2nm, even more preferably A thickness of at most 1 nm, most preferably at most 0.9 nm. These preferred thicknesses can make deposition easier and improve optical properties such as haze while maintaining mechanical durability.

[0088] The one (or more) layers of Zn-based oxide and/or Ti-based oxide of the intermediate anti-reflection layer may independently preferably have at least 1 nm, more preferably at least 2 nm, even more preferably at least 3 nm, and most preferably at least 3.5nm; but preferably a thickness of at most 10nm, more preferably at most 7nm, even more preferably at most 5nm, most preferably at most 4nm. These preferred thicknesses can make deposition easier and improve optical properties such as haze while maintaining mechanical durability.

[0089] The intermediate anti-reflection layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn may preferably have at least 5 nm, more preferably at least 10 nm, even more preferably at least 13 nm, and most preferably at least 14 nm ; But preferably a thickness of at most 40 nm, more preferably at most 30 nm, even more preferably at most 25 nm, most preferably at most 21 nm.

[0090] Si-based (oxy)nitride of the intermediate anti-reflection layer, and/or Al (oxy)nitride, and/or alloys thereof, and/or oxidation of Al, Si, Ti, and/or Zr The layer of the substance may preferably have at least 5nm, more preferably at least 15nm, even more preferably

At least 25nm, most preferably at least 30nm; but preferably at most 60nm, more preferably at most 50nm, even more preferably at most 45nm, most preferably at most 40nm in thickness.

[0091] The upper anti-reflection layer may include at least one combination of one or more of the following layers:

[0092] NiCr-based oxide layer;

[0093] A layer based on an oxide of Zn and/or an oxide of Ti;

[0094] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or Al, Si, Ti, and/or Zr oxide layers; and

[0095] A layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn.

[0096] In some preferred embodiments, the upper anti-reflection layer comprises at least:

[0097] A barrier layer based on Zn oxide;

[0098] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or Al, Si, Ti, and/or Zr oxide layers; and

[0099] A layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn.

[0100] In some other preferred embodiments, the upper anti-reflection layer comprises at least:

[0101] NiCr-based oxide barrier layer;

[0102] A barrier layer based on Zn oxide;

[0103] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or Al, Si, Ti, and/or Zr oxide layers, and

[0104] A layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn.

[0105] The Zn-based oxide and/or Ti-oxide-based barrier layer of the upper anti-reflection layer may preferably have at least 1 nm, more preferably at least 2 nm, even more preferably at least 3 nm, and most preferably at least 3.5 nm; but preferably A thickness of at most 10 nm, more preferably at most 7 nm, even more preferably at most 5 nm, most preferably at most 4 nm. These preferred thicknesses can make deposition easier and improve optical properties such as haze while maintaining mechanical durability.

[0106] It has been found that if the barrier layer contains a mixed metal oxide layer sputtered by a mixed metal oxide target, excellent protection of the one (or more) functional layers during the deposition process can be obtained and the High optical stability during heat treatment. When the barrier layer is based on an oxide of Zn, the oxide may be a mixed metal oxide such as ZnO:Al. Especially if the ZnO:Al-based layer is sputtered by a conductive ZnO:Al target, good results are achieved. ZnO: Al can be completely oxidized deposited or made to be slightly sub-oxidized. Preferably the ZnO:Al barrier layer is substantially stoichiometric. The use of a substantially stoichiometric ZnO:Al barrier layer, instead of a metallic or less than 95% stoichiometric ZnO:Al barrier layer, leads to extremely high optical stability of the coating during the heat treatment process, and during the heat treatment process Effectively assist in keeping small optical changes. In addition, the use of barrier layers based on substantially stoichiometric metal oxides provides benefits in terms of mechanical strength.

[0107] When the barrier layer is based on NiCr oxide, it is preferably deposited as a substoichiometric oxide. This enables the layer to act as an oxygen scavenger/absorbent during heat treatment.

[0108] Preferably, non-reactive sputtering of an oxidizing target is used to deposit at least a part of the barrier layer in direct contact with the functional layer to avoid damage to the functional layer.

[0109] The barrier layer is preferably deposited by non-reactive sputtering. The barrier layer is preferably sputtered by a ceramic target. In this hair

In a clear context, the term "non-reactive sputtering" includes sputtering an oxidizing target in a low oxygen atmosphere (no oxygen or up to 5% by volume oxygen) to provide a substantially stoichiometric oxide.

[0110] When the barrier layer is based on TiOx, x may be from 1.5 to 2.0.

[0111] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or oxides of Al, Si, Ti, and/or Zr of the upper anti-reflection layer The layer of may preferably have a thickness of at least 2nm, more preferably at least 5nm, even more preferably at least 10nm, most preferably at least 15nm; but preferably at most 40nm, more preferably at most 35nm, even more preferably at most 30nm, most preferably at most 25nm. Such a thickness provides a further improvement in the mechanical strength of the coated board. The layer of (oxy)nitride based on Si, and/or (oxy)nitride of Al, and/or alloys thereof, and/or oxides of Al, Si, Ti and/or Zr may preferably directly contact the Barrier layer.

[0112] The Si-based (oxy)nitride, and/or Al (oxy)nitride, and/or its alloy, and/or Al, Si, Ti, and/or Zr oxide layer (which is in In some cases, it can form the main part of the upper anti-reflection layer) to provide stability (better protection during heat treatment) and diffusion barrier properties. Preferably, the layer is deposited as an aluminum nitride and/or silicon nitride layer by reactive sputtering of Si, Al or a mixed SiAl target (eg Si90Al10 target) in a N2 containing atmosphere. The composition of the layer based on Al (oxy)nitride and/or Si (oxy)nitride may be substantially stoichiometric Si90Al10Nx.

[0113] The upper anti-reflection layer based on a metal oxide such as an oxide of Zn and Sn and/or an oxide of Sn may preferably have at least 1 nm, more preferably at least 5 nm, even more preferably at least 7 nm, and most preferably at least 9nm; but preferably a thickness of at most 20nm, more preferably at most 15nm, even more preferably at most 13nm, most preferably at most 11nm. Such a thickness provides a further improvement in the mechanical strength of the coated board. When the layer is an oxide of Zn and Sn, it preferably contains about 10-90wt.% Zn and 90-10wt.% Sn, more preferably about 40-90wt.% in wt.% of its total metal content. 60wt.% Zn and about 4060wt.% Sn, preferably Zn and Sn are each about 50wt.%. In some preferred embodiments, the layer based on oxides of Zn and Sn of the upper anti-reflection layer may contain at most 18 wt.% Sn, more preferably at most 15 wt.% Sn, even more preferably at most 10 wt.% Sn. The layer can be mixed with a ZnSn target. 2 Reactive sputtering in the presence of deposition, and contributes to the anti-reflection properties of the upper anti-reflection layer.

[0114] Si-based (oxy)nitrides, and/or Al (oxy)nitrides, and/or alloys thereof, and/or oxides of Al, Si, Ti, and/or Zr of the upper anti-reflection layer The layer of may be in direct contact with the metal oxide-based layer of the upper anti-reflection layer as defined herein, without any intervening additional dielectric layer.

[0115] Preferably, the metal oxide-based layer of the upper anti-reflection layer includes a layer based on an oxide of Zn and Sn and/or an oxide of Sn.

[0116] The upper anti-reflection layer may have a total thickness of from 20 to 60 nm, preferably from 25 to 50 nm, more preferably from 30 to 50 nm, even more preferably from 35 to 45 nm.

[0117] A protective layer can be deposited as the top layer (outermost layer) of the upper anti-reflection layer for increased mechanical and/or chemical strength, such as scratch resistance. The protective layer may include a layer based on oxides of Al, Si, Ti, and/or Zr.

[0118] In order to reduce the increase in light transmittance during the heat treatment, it is preferable to deposit all the individual layers of the upper, middle and lower anti-reflection layers with a substantially stoichiometric composition.

[0119] In order to further optimize the optical properties of the coated plate, the upper and/or lower anti-reflection layer may contain additional partial layers composed of well-known dielectrics for low emissivity and/or solar control coatings. The layer is composed of a suitable material, in particular selected from Sn, Ti, Zn, Nb, Ce, Hf, Ta, Zr, Al and/or Si oxide, and/or Si (oxy)nitride and / Or Al (oxy)nitride, or one or more of its combination. However, when adding such an additional partial layer, it should be confirmed that the heat treatability intended herein is not impaired thereby.

[0120] It will be understood that any additional partial layer may contain additives that modify its properties and/or facilitate its manufacture, such as dopants or reaction products of reactive sputtering gases. In the case of an oxide-based layer, nitrogen can be added to the sputtering atmosphere, resulting in the formation of oxynitride instead of oxide, and in the case of a nitride-based layer, oxygen can be added to the sputtering atmosphere, thereby also This results in the formation of oxynitrides instead of nitrides.

[0121] It must be noted that when adding any such additional partial layers to the basic layer sequence of the board of the present invention, by making suitable material, structure and thickness selections, the main intended properties are not thereby significantly impaired, such as High thermal stability.

[0122] According to a second aspect of the present invention, there is provided a coated glass sheet manufactured by the method according to the first aspect of the present invention.

[0123] According to a third aspect of the present invention, there is provided a coated glass plate comprising:

[0124] a) a glass substrate,

[0125] b) At least one coating layer on the surface of the glass substrate, wherein the coating layer comprises at least one titanium oxide-based crystalline layer, wherein the at least one crystal layer furthest from the glass substrate The main surface of the state layer has an arithmetic mean surface height value Sa of at most 3 nm, and

[0126] c) at least one additional coating on the at least one coating, wherein the at least one additional coating comprises at least one reflective metal-based functional layer.

[0127] It was surprisingly found that, compared with known plates, these coated plates exhibit improved optical properties both before and after heat treatment. In addition, the present invention avoids the need to use a nitride-based layer as the base layer of the lower anti-reflection layer. In addition, this coated plate has the following benefits: it allows the base coating of the multilayer coating stack to be manufactured by CVD instead of PVD, which reduces the number of cathodes required.

[0128] Preferably, CVD is used to deposit the at least one coating (ie, the coating is a CVD coating). Preferably, TTIP is used as a precursor to deposit the at least one titanium oxide-based layer.

[0129] Preferably, PVD is used to deposit the at least one additional coating (ie, the additional coating is a PVD coating).

[0130] The at least one titanium oxide-based layer is preferably arranged in direct contact with the at least one additional coating.

[0131] Preferably, the main surface of the at least one crystalline layer furthest from the glass substrate has an arithmetic mean surface of at most 2 nm, more preferably at most 1 nm, even more preferably at most 0.7 nm, most preferably at most 0.5 nm The height value Sa. Preferably, the main surface of the at least one crystalline layer has an Sa of at least 0.1 nm.

[0132] Preferably, the coated sheet further comprises a lower anti-reflection layer located between the glass substrate and the at least one functional layer. The at least one additional coating layer may preferably further comprise at least one layer based on a dielectric material between the at least one coating layer deposited on the surface of the glass substrate and the at least one functional layer.

[0133] Preferably the at least one additional coating layer further comprises an upper anti-reflection layer on the functional layer.

[0134] According to a fourth aspect of the present invention, there is provided a multilayer window glass incorporating the coated glass sheet according to the present invention. For example, the multilayer window glass may be laminated glass or insulating glass.

[0135] According to a fifth aspect of the present invention, there is provided the use of titanium tetraisopropoxide (TTIP) as a precursor in chemical vapor deposition (CVD) of at least one CVD coating on the surface of a glass substrate. Chemical vapor deposition (CVD) precedes physical vapor deposition (PVD) of the at least one PVD coating on the at least one CVD coating.

[0136] It will be understood that optional features applicable to an aspect of the invention can be used in any combination and in any number. In addition, it can also be used with any other aspect of the present invention in any combination and in any number. This includes, but is not limited to, the use of a dependent claim of any claim as a dependent claim of any other claim in the claims of this application.

[0137] The readers attention is directed to all papers and documents related to this application that are submitted at the same time or earlier with the application and are open to the public together with this application, and all such papers and documents are cited by reference. The content is incorporated into this article.

[0138] All the features disclosed in this application document (including any appended claims, abstract and drawings) and/or all steps of any method or process disclosed thereby can be combined in any combination, at least some of which are Except for mutually exclusive combinations of features and/or steps.

[0139] Unless expressly stated otherwise, each feature disclosed in this application (including any appended claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose. Therefore, unless expressly stated otherwise, the disclosed features are merely an example of equivalent or similar features in a general series.

[0140] The present invention will now be further described by the following specific embodiments given in an illustrative and non-limiting manner:

[0141] For all examples, the coating was deposited on a 4 mm thick standard float glass plate (10 cm×10 cm) with a light transmittance of about 88%. Before coating, the glass was washed twice on a Benteler (RTM) washing machine.

[0142] The multilayers of Comparative Example 1 were all deposited using PVD. For Example 2, CV D was used to deposit TiO_xBase layer, and use PVD to deposit other layers. For Comparative Example 3, C VD was used to deposit SiO_xAnd TiOx base layer, and use PV D to deposit other layers.

[0143] For the CVD coating, the glass was heated on a belt furnace to simulate the coating reaction conditions of the float glass process. The furnace utilizes in-line rollers to transport the glass substrate through the heating zone before the CVD. For Comparative Example 3 of a glass substrate initially provided with a silicon oxide coating, the coating was deposited on the float glass by a known CVD process using a monosilane precursor in an oxygen-rich atmosphere.

[0144] The titanium oxide coating was deposited by CV D at a substrate temperature of about 630°C. In order to deposit the titanium oxide, a precursor gas mixture containing TTIP or TiCl4 with ethyl acetate, oxygen and helium was developed. The precursor mixture contains helium as a carrier for the reactant. The precursor mixture is prepared by simultaneously introducing all four gas streams through the manifold system. A pipeline static mixer is used to ensure a uniform precursor mixture.

[0145] Keep the temperature of the precursor mixture above 150C to prevent the addition reaction of TTIP or TiCl4 with ethyl acetate. The precursor temperature is also kept below the 510C-610C thermal decomposition temperature range of ethyl acetate to prevent pre-reaction of the mixture. The precursor mixture is introduced into the reactor just above the moving substrate. The temperature at the precursor tower is 120C. The temperature at the reactor surface is 175C. The higher substrate temperature causes the thermal decomposition of the ethyl acetate, which subsequently leads to the deposition of titanium oxide.

[0146] The resulting coated glass was allowed to cool in air, and the coating was analyzed before deposition of the PVD coating.

[0147] An AC and/or DC magnetron sputtering device is used, and intermediate frequency sputtering is applied when appropriate to deposit the PVD coating.

[0148] Reaction sputtering of oxides of Zn and Sn (ZnSnOx, weight ratio Zn:Sn^) from a zinc-tin target in an Ar/O2 sputtering atmosphere

50:50) all dielectric layers.

[0149] A Zn target doped with Al (Al content is about 2 wt. %) was sputtered in an Ar/O 2 sputtering atmosphere to sputter the ZnO: Al growth promoting top layer of the lower anti-reflection layer.

[0150] With a silver target in an Ar sputtering atmosphere without any added oxygen and at a temperature lower than 10^-5The functional layer composed of substantially pure silver (Ag) in all the examples was sputtered at a residual oxygen partial pressure of mbar.

[0151] A barrier layer of Al-doped zinc oxide (ZnO:Al, ZAO) was sputtered from a conductive ZnOx:Al target in a pure Ar sputtering atmosphere without added oxygen.

CN 105517968 Β

[0152] From the mixed Si_9OThe Aho target reactively sputters a mixed silicon aluminum nitride (SigoAhoNx) layer in an Ar/Nz sputtering atmosphere containing only residual oxygen.

[0153]

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<td colspan="2"></td><td>Example 1 (Comparative Example) SiM 34nm / ZnSnO, 5nm / TiO, 2nm / ZAO 8nm / Ag 9nm / ZAO 2nm / ZnSnOz 2nm / ZAO 4nm / SiN, 27nm / ZnSnO, 9nm</td><td>Example 2TiR (deposited by TTIP) 20nm / ZnSnO. 5nm / TlOj 2nm / ZAO 8nm / Ag 9nm / ZAO 2nm / ZnSnh 2nm / ZAO 4nm / SiN, 27nm / ZnSnO, 9nm</td><td>Example 3 (Comparative Example) SiO, 30nm / TiO_s (Using TiCl₄Deposited) 18nm / ΖηδηΟϊ 5nm / TiQ 2nm / ZAO 8nm / Ag 9nm / ZAO 2nm / ZnSnO, 2nm / ZAO 4nm / SiN, 27nm / ZnSnO, 9nm</td>

[0154] Table 1: Haze scores, light transmittance, sheet resistance, emissivity and oil rub test scores of a plurality of comparative coated glass plates and coated glass plates according to the present invention; where: AD = deposition state ,HT=after heat treatment, %Tl=percent light transmittance, %A=percent absorbance, Rs=sheet resistance, ε=emissivity, and Sa=arithmetic average surface height value. The methods used to collect the data in Table 1 are listed below. In Table 1, for each example, multiple layers were deposited on the glass plate in the order starting from the first layer shown.

[0155] Heat Treatability Test

[0156] After depositing the coatings of Examples 1-3, T1, A, R s, and emissivity were measured, and the samples were heat-treated at about 650° C. for about 5 minutes. After that, the haze, Tl, A, Rs, and emissivity were measured. The results are listed in Table 1 above.

[0157] The values stated for the% light transmittance (%Tl) of the coated glass plates in Examples 1-3 are derived from measurements according to EN 140.

[0158] The visible haze scoring system was applied to the examples. It is found that the quality evaluation system described below is needed to better distinguish the visual quality of the coating under bright light conditions, which cannot be completely reflected by the standard haze value measured according to ASTM D 1003-61.

[0159] Specular-haze (sometimes called red haze or white haze to describe certain color shifts associated with it) can be regarded as a milky white or fine mottle pattern covering most of the coated glass surface . As the name suggests, its essence seems to be that the mirror is dominant rather than diffuse, but it is not entirely a mirror. This means that these patterns can often have a strong angular component to their behavior, that is, if the light source and the observer's viewing angle are incident in the normal direction, the specular haze may be obvious, and if the light source is moved to a completely different angle (for example, 45 °), it may not be obvious.

[0160] This evaluation system considers the more macroscopic effects of visible defects in the coating that cause local color changes where the coating is damaged or imperfect (haze score in Table 1). The macroscopic effects of visible defects in the coating after heat treatment were subjectively assessed by observing the samples under bright light (all examples did not show haze before heat treatment). The evaluation is based on a perfection score (rating) system, which uses 0 (perfect, no defects), through 3 (some clearly visible defects and/or spots), up to 5 (dense haze, often visible to the naked eye) Score, to rate the visual appearance of the coated glass sample after heat treatment. Heat-treated coated glass panels with any score &gt;3 are considered to have failed the test. Although a non-zero specular haze score is generally obtained, as long as the haze is uniform and randomly distributed, it is not a problem in the case of low values. If concentrated into patterns or areas with very high haze, this becomes visually distracting and unacceptable (ie failure). These local and/or uneven patterns in the haze can take the form of blocks, spots, or stains.

[0161] The visual evaluation was performed by the following method: 2.5 million candle beams (flame) were used in two orthogonal planes at an angle of incidence between about -90° to about +90° (relative to normal incidence) (Ie first flip the flame in the horizontal plane, then flip the flame in the vertical plane) to guide it to the coated glass plate arranged in front of the black box. The black box has a size large enough that several coated glass samples can be evaluated at the same time. Observe the coated glass plate by changing the incident angle as described above and by directing the light beam from the observer to the coated glass plate and evaluate its visual quality. The coated glass plate is arranged in front of the black box so that its coating faces the observer.

[0162] Mechanical strength test

[0163] The oil rub test is used to simulate the effect of cutting oil used to cut glass plates on the mechanical strength of the coating. Coated glass plates that cannot withstand the oil rub test will be difficult to process and are not suitable for most practical applications. The use area is 1.2*1.2cm²And a felt pad impregnated with a microscope oil with a refractive index of 1.515-1.517 to rub the sample. The sample was subjected to 500 cycles at a rate of 37 cycles per minute with a load of 900 g. The oil rub sample was evaluated using an internal evaluation system based on a perfection score of 0 (perfect, no damage) to 9 (the coated stack is completely separated). Less than or

A score equal to 1 is considered acceptable.

[0164] As will be explained herein below, the coated glass sheet of Example 2 not only proved to be heat treatable (as reflected by the low haze score after heat treatment), but also simulated the processing of the coated glass sheet And the oil rub test of the treatment showed better results than the coated board of Comparative Example 1. The results are shown in Table 1.

[0165] Roughness data-arithmetic mean surface height value, Sa

[0166] The Sa value was obtained according to ISO 25178 using atomic force microscopy.

[0167] Summary of Results

[0168] Table 1 shows that the board of Example 2 exhibits high visible light transmittance before and after heat treatment, which is similar to all sputtering Comparative Example 1, and is better than using TiCl4 as the pre-treatment for the TiOx base layer. The body of Comparative Example 3 is higher (far higher in the heat-treated sample).

[0169] Example 2 exhibited low absorption before and after the heat treatment, exhibiting lower absorption than Comparative Example 1 before the heat treatment, and the same absorption as Comparative Example 1 after the heat treatment. In addition, both before and after the heat treatment, the absorption shown by Example 2 was much lower than that of Comparative Example 3.

[0170] The haze exhibited by the panel of Example 2 after the heat treatment was acceptable, while the panel of Comparative Example 3 showed an unacceptably high level of haze.

[0171] In addition, as described above, the board of Example 2 performed better than Comparative Example 3, and even better than Comparative Example 1 in the oil rub test.

[0172] Table 1 also shows that the board of Example 2 exhibits the sheet resistance and emissivity of the board of Comparative Example 1 before and after the heat treatment that are comparable to, and much better (lower) than that of the board of Comparative Example 3. value.

[0173] The base TiOx layer of Example 2 exhibited an Sa value comparable to the sputtered base layer of SiNx of Comparative Example 1, and far lower than the Sa value of the base TiOx layer of Comparative Example 3. As detailed in paragraph 3 on page 6, a smoother CVD coating can facilitate the deposition of a smoother PVD coating and is considered to be advantageous because the resulting coated board exhibits less Absorption and low sheet resistance (Rs). In addition, the board of Example 2 of the present invention showed better sheet resistance (lower) and better than any of the three examples of WO 2012052749A1 (see page 7, Table 3) before and after heat treatment. Visible light transmittance (higher), and better haze.

[0174] Similarly, the plate of Example 2 of the present invention showed better light transmittance before and after heat treatment than any of the four examples of WO 00/32530A1 (see page 9, Table 3) . Moreover, the emissivity value of the board of Example 2 of the present invention is similar to the emissivity value of the four embodiments of WO 00/32530A1.

[0175] The present invention is not limited to the details of the above-described embodiments. The present invention extends to any novel single feature or any novel combination of features disclosed in this application document (including any appended claims, abstract and drawings), or to any method or process step disclosed thereby Any novel single step or any novel combination.