Light-weight hybrid glass laminates

Description of related application

0001This application claims the priority of US Provisional Patent Application No. 61/500766 filed on June 24, 2011 under US Code 35, Section 199, and September 28, 2011. It claims the benefit of priority under US Code 35, Article 120 of the US Patent Application No. 13/274182 filed in Japan, and the content of these applications is relied upon and all cited herein. Will be done.

The present disclosure broadly relates to laminated glass, and more particularly to hybrid laminated glass including chemically strengthened outer glazing and non-chemically reinforced inner glazing. Such composite laminated glass will be characterized by light weight, good sound damping performance, and high impact resistance. In particular, the disclosed composite laminated glass meets industrially applicable impact test criteria for applications other than windshields.

Laminated glass can be used as windows and glazing in building applications and in transportation applications including automobiles, rolling stock and airplanes. As used herein, glazing is a transparent or translucent member of a wall or other structure. A common type of glazing used in architectural and automotive applications is laminated glass. Examples include transparent glass and colored glass, including glass). For example, laminated glazing consisting of opposing glass plates separated by soft poly (vinyl butyral) (PVB) can be used as a window, windshield, or sunroof. In some applications, laminated glass with high mechanical strength and acoustic attenuation properties is desirable in order to provide a safe barrier while reducing acoustic transmission from external sources. In many vehicle applications, fuel economy is a function of vehicle weight. Therefore, it is desirable to reduce the mass of glazing for such applications without compromising intensity and acoustic damping properties. Laminated glass is mechanically robust with respect to external contact events such as attempted penetration or contact with stones or hail, yet the energy (and) as a result of internal impact events such as contact with occupants during a collision. It is convenient to dissipate cracks properly.

<p num="0004"> In view of the above, a thin lightweight glazing with the durability and sound damping properties associated with thicker and heavier glazing is desirable.</p>

<p num="0005"> According to one aspect of the present disclosure, the laminated glass comprises an outer glass plate, an inner glass plate, and a polymer intermediate layer formed between the outer and inner glass plates. To optimize the impact behavior of laminated glass, the outer glass plate is made of chemically strengthened glass and can have a thickness of 1 mm or less, while the inner glass plate is made of non-chemically tempered glass and is 2.5 mm or less. Can have a thickness of. In embodiments, the polymer intermediate layer (eg, poly (vinyl butyral) or PVB) can have a thickness of 1.6 mm or less. It is convenient that the disclosed composite laminated glass structure can distribute stress to impact. For example, the disclosed laminated glass can provide excellent impact resistance and can resist fracture to external impact events, yet properly dissipate energy and crack appropriately against internal impact events.</p><p num="0006"> Additional features and advantages of the present invention are set forth in the detailed description below, some of which will be readily apparent to those skilled in the art, or the detailed description below, claims, It will also be recognized by practicing the invention described herein, including the accompanying drawings.</p><p num="0007"> Both the general description above and the detailed description below present embodiments of the invention and are an overview or a summary for understanding the nature and features of the invention as described in the claims. It will be understood that it is intended to provide the gist. The accompanying drawings are included for further understanding of the present invention, are included in the present specification, and form a part thereof. The drawings illustrate and explain various embodiments and serve to explain the principles and operations of the present invention.</p>

<figref num="1">Explanatory drawing of an exemplary flat composite laminated glass according to an embodiment</figref><figref num="2">Explanatory drawing of an exemplary bent composite laminated glass according to an embodiment</figref>

The laminated glass disclosed herein is configured to include an outer chemically strengthened glass plate and an inner non-chemically strengthened glass plate. As defined herein, when laminated glass is actually used, the outer glass plate is close to or in contact with the environment, while the inner glass plate is a structure or vehicle in which the laminated glass is incorporated (eg,). Close to or touch the interior (eg, guest room) of the car).

An exemplary laminated glass is shown in Figure 1. The laminated glass 100 includes an outer glass plate 110, an inner glass plate 120, and a polymer intermediate layer 130. This polymer interlayer may be in direct physical contact (eg, bonded) with each of the outer and inner glass plates. The outer glass plate 110 has an outer surface 112 and an inner surface 114. In a similar context, the inner glass plate 120 has an outer surface 122 and an inner surface 124. As shown in the illustrated embodiment, the inner surface 114 of the outer glass plate 110 and the inner surface 124 of the inner glass plate 120 are in contact with the polymer intermediate layer 130, respectively.

During use, the laminated glass should resist cracking in response to external impact events. However, in the event of an internal impact event, such as when a vehicle occupant hits the laminated glass, the laminated glass retains the occupant in the vehicle and still provides energy in the event of a collision to minimize injury. It is desirable to dissipate. The ECE R43 head test, which simulates a collision event originating from inside a vehicle, is a regulatory test that requires laminated glazing to crack under a specific internal collision.

Although not intended to be constrained by theory, when a single laminated glass of glass plate / polymer interlayer / glass plate is impacted, the opposite side and the opposite side of the impacted plate The outer surface of the board is placed in tension. Due to the stress distribution calculated for the laminated glass of the glass plate / polymer intermediate layer / glass plate under biaxial load, the magnitude of the tensile stress on the opposite surface of the impacted plate is that of the opposite plate with the lower load velocity. It will be comparable (or even slightly greater) to the magnitude of the tensile stress experienced on the outer surface. However, at high load speeds, which is a characteristic of impact typically experienced in automobiles, the magnitude of the tensile stress on the outer surface of the opposite plate is the tensile stress on the opposite surface of the impacted plate. Will be much larger than. As disclosed herein, the composite laminated glass is configured to have a chemically reinforced outer glass plate and a non-chemically reinforced inner glass plate to optimize impact resistance for both external and internal impact events. be able to.

A suitable inner glass plate is a non-chemically tempered glass plate such as soda-lime glass. If necessary, the inner glass plate may be heat-reinforced. In embodiments where soda-lime glass is used as a non-chemically tempered glass plate, conventional decorative materials and methods (eg, glass frit enamel and screen printing) can be used, which simplifies the laminated glass manufacturing process. Can be. A colored soda-lime glass plate can be incorporated into the composite laminated glass to achieve the desired transmission and / or attenuation over the electromagnetic spectrum.

Suitable outer glass plates may be chemically strengthened by an ion exchange process. In this process, generally, by immersing the glass plate in a molten salt bath for a predetermined period of time, ions on or near the surface of the glass plate are exchanged for larger metal ions from the salt bath. In one embodiment, the temperature of the molten salt bath is about 430 ° C and the predetermined period is about 8 hours. The uptake of larger ions into the glass strengthens the plate by creating compressive stresses in the area near the surface. A corresponding tensile stress is evoked in the central region of the glass to balance its compressive stress.

Illustrative ion exchangeable glasses suitable for forming composite laminated glasses are alkaline aluminosilicate glass or alkaline aluminosilicate glass, but other glass compositions are also conceivable. As used herein, "ion-exchangeable" means that a glass refers to cations located on or near the surface of the glass as cations of the same valence that are larger or smaller in size. It means that it can be exchanged. An example glass composition is SiO₂, B₂O₃And Na₂Including O, where (SiO₂+ B₂O₃) 66 mol%, and Na₂O 9 mol%. In one example, the glass plate contains at least 4% by weight of aluminum oxide. In yet another embodiment, the glass plate comprises one or more alkaline earth oxides such that the content of the alkaline earth oxides is at least 5% by weight. Suitable glass compositions, in some embodiments, K₂It further comprises at least one of O, MgO, and CaO. In a particular embodiment, the glass is 61-75 mol% SiO.₂, 7 ~ 15 mol% Al₂O₃, 0-12 mol% B₂O₃, 9-21 mol% Na₂O, 0-4 mol% K₂It may contain O, 0-7 mol% MgO, and 0-3 mol% CaO.

Yet another exemplary glass composition suitable for forming composite laminated glass is 60-70 mol% SiO.₂, 6-14 mol% Al₂O₃, 0 ~ 15 mol% B₂O₃, 0-15 mol% Li₂O, 0-20 mol% Na₂O, 0-10 mol% K₂O, 0-8 mol% MgO, 0-10 mol% CaO, 0-5 mol% ZrO₂, 0 ~ 1 mol% SnO₂, 0 ~ 1 mol% CeO₂, As less than 50ppm₂O₃, And Sb less than 50ppm₂O₃Including, 12 mol% (Li₂O + Na₂O + K₂O) 20 mol% and 0 mol% (MgO + CaO) 10 mol%.

Yet another exemplary glass composition is 63.5-66.5 mol% SiO.₂, 8-12 mol% Al₂O₃, 0-3 mol% B₂O₃, 0-5 mol% Li₂O, 8-18 mol% Na₂O, 0-5 mol% K₂O, 1-7 mol% MgO, 0-2.5 mol% CaO, 0-3 mol% ZrO₂, 0.05 ~ 0.25 mol% SnO₂, 0.05-0.5 mol% CeO₂, As less than 50ppm₂O₃, And Sb less than 50ppm₂O₃Including, 14 mol% (Li₂O + Na₂O + K₂O) 18 mol% and 2 mol% (MgO + CaO) 7 mol%.

In a particular embodiment, the alkali aluminosilicate glass is alumina, at least one alkali metal, and in some embodiments greater than 50 mol% SiO.₂, At least 58 mol% SiO in other embodiments₂, Yet in still other embodiments, at least 60 mol% SiO₂Including, where the ratio<img id="000002" he="17" wi="42" file="JP5890518B2_D0001.tif" img-format="tif" img-content="drawing" />

In the formula, in this ratio, the component is represented by mol% and the modifier is an alkali metal oxide. This glass, in a special embodiment, is 58-72 mol% SiO₂, 9-17 mol% Al₂O₃, 2-12 mol% B₂O₃, 8-16 mol% Na₂O, and 0-4 mol% K₂Containing, becoming substantial, or consisting of, where the ratio<img id="000003" he="17" wi="42" file="JP5890518B2_D0001.tif" img-format="tif" img-content="drawing" />

Is.

In another embodiment, the alkaline aluminosilicate glass is 61-75 mol% SiO.₂, 7 ~ 15 mol% Al₂O₃, 0-12 mol% B₂O₃, 9-21 mol% Na₂O, 0-4 mol% K₂Containing, consisting of, or consisting of O, 0-7 mol% MgO, and 0-3 mol% CaO.

In yet another embodiment, the alkaline aluminosilicate glass is 60-70 mol% SiO.₂, 6-14 mol% Al₂O₃, 0 ~ 15 mol% B₂O₃, 0-15 mol% Li₂O, 0-20 mol% Na₂O, 0-10 mol% K₂O, 0-8 mol% MgO, 0-10 mol% CaO, 0-5 mol% ZrO₂, 0 ~ 1 mol% SnO₂, 0 ~ 1 mol% CeO₂, As less than 50ppm₂O₃, And Sb less than 50ppm₂O₃Including, 12 mol% Li₂O + Na₂O + K₂O 20 mol% and 0 mol% MgO + CaO 10 mol%.

In yet another embodiment, the alkaline aluminosilicate glass is 64 to 68 mol% SiO.₂, 12-16 mol% Na₂O, 8-12 mol% Al₂O₃, 0-3 mol% B₂O₃, 2-5 mol% K₂Contains O, 4-6 mol% MgO, and 0-5 mol% CaO, and consists of, or consists of, where 66 mol% SiO₂+ B₂O₃+ CaO 69 mol%, Na₂O + K₂O + B₂O₃+ MgO + CaO + SrO&gt; 10 mol%, 5 mol% MgO + CaO + SrO 8 mol%, (Na₂O + B₂O₃)-Al₂O₃2 mol%, 2 mol% Na₂O-Al₂O₃6 mol%, and 4 mol% (Na₂O + K₂O) -Al₂O₃10 mol%.

In some embodiments, chemically tempered and non-chemically tempered glass, Na₂SO₄, NaCl, NaF, NaBr, K₂SO₄, KCl, KF, NKr, and SnO₂At least one fining agent selected from the group containing 0 to 2 mol% is batch-blended.

In one exemplary embodiment, the sodium ions in the chemically strengthened glass can be replaced by potassium ions from the molten batch, but by other alkali metal ions with a larger atomic radius, such as rubidium or cesium, the glass. It does not matter if the smaller alkali metal ions inside are replaced. According to certain embodiments, the smaller alkali metal ions in the glass are Ag⁺Can be replaced by ions. Similarly, other alkali metal salts such as sulfates and halides may be used in the ion exchange process, but not limited to:

At temperatures below the temperature at which the glass network structure can be relaxed, the replacement of smaller ions with larger ions results in a distribution of ions over the surface of the glass, which results in a stress profile. The larger volume of incoming ions creates a compressive stress (CS) on the surface of the glass and a tension (central tension, or CT) in the center. This compressive stress has the following relational expression:

<maths num="1"><img id="000004" he="19" wi="47" file="JP5890518B2_D0001.tif" img-format="tif" img-content="drawing" /></maths>

In the equation, t is the total thickness of the glass plate and DOL is the depth of exchange, also referred to as the depth of the layer.

According to various embodiments, composite laminated glass, including ion exchange glass, has many desired properties, including light weight, high impact resistance, and improved acoustic attenuation.

In one exemplary embodiment, the chemically strengthened glass plate has a surface compressive stress of at least 300 MPa, eg at least 400, 450, 500, 550, 600, 650, 700, 750 or 800 MPa, at least about 20 μm (eg at least about 20 μm). Layer depth of about 20, 25, 30, 35, 40, 45, or 50 μm) and / or greater than 40 MPa (eg, greater than 40, 45, or 50 MPa), but less than 100 MPa (eg, 100, 95). , 90, 85, 80, 75, 70, 65, 60, or less than 55 MPa).

The elastic modulus of the chemically strengthened glass plate can range from about 60 MPa to 85 GPa (eg 60, 65, 70, 75, 80 or 85 GPa). The elastic modulus of the glass plate and the polymer interlayer can affect both the mechanical properties (eg, deflection and strength) and acoustic performance (eg, transmission loss) of the resulting laminated glass.

Examples of the glass plate forming method include a fusion draw method, a slot draw method, and a float method, both of which are examples of the down draw method. These methods can be used to form both chemically tempered and non-chemically tempered glass plates. In the fusion draw method, a plate drawing tank having a passage for receiving the molten glass raw material is used. This passage has weirs open at the top on both sides of the passage along the longitudinal direction of the passage. The molten glass overflows the weir when the passage is filled with molten material. Due to gravity, the molten glass flows down to the outer surface of the plate pulling tank. These outer surfaces extend downward and inward so as to join at the lower edge of the boarding tank. The two flowing glass surfaces join and fuse at this edge to form a single flowing plate. The fusion draw method presents the advantage that neither outer surface of the resulting glass plate touches any part of the device, as the two glass films flowing across the aisle fuse together. Therefore, the surface properties of the glass plate by the fusion draw method are not affected by such contact.

The slot draw method is distinguished from the fusion draw method. Here, the molten glass raw material is supplied to the plate drawing tank. At the bottom of the boarding tank is an open slot, which has a nozzle that extends over the length of the slot. The molten glass flows through the slots / nozzles and is pulled downward into the slow cooling region as a continuous plate. The slot draw method can provide thinner plates than the fusion draw method because the two plates are not fused together, but only one plate is pulled through the slot.

The downdraw method produces a glass plate of uniform thickness with a relatively solid surface. Since the strength of the glass plate is controlled by the amount and size of surface scratches, a solid surface with minimal contact has a high initial strength. When this high-strength glass is then chemically fortified, the resulting strength can be higher than that of a wrapped and polished surface. Glass by the downdraw method can be stripped to a thickness of less than about 2 mm. Moreover, down-draw glass has a very smooth surface that can be used in end applications without costly grinding and polishing.

In the float method, a glass plate characterized by a smooth surface and uniform thickness is produced by suspending molten glass on a floor of molten metal, typically tin. In the illustrated process, the molten glass fed onto the surface of the molten tin bed forms a floating ribbon. As the glass ribbon flows along the tin bath, the temperature gradually decreases until the solid glass plate is lifted from the tin to the rollers. Once away from the tin bath, the glass plate can be further cooled and slowly cooled to reduce internal stress.

A glass plate can be used to form the laminated glass. As defined herein, composite laminated glass comprises a chemically strengthened glass plate facing outward, a non-chemically strengthened glass plate facing inward, and a polymer interlayer formed between the glass plates. The polymer intermediate layer may include a monolith polymer plate, a multilayer polymer plate, or a composite polymer plate. The polymer intermediate layer may be, for example, a soft poly (vinyl butyral) plate.

Laminated glass can be adapted to provide an optically transparent barrier for structural openings and automotive openings, such as automotive glazing. Laminated glass can be formed using a wide variety of processes. In an exemplary embodiment, the assembly involves placing a first glass plate, covering a polymer interlayer such as a PVB plate, placing a second glass plate, and then excessing the edges of the glass plate. Includes the process of cutting out the PVB of. The joining process may include expelling most of the air from the interface and partially bonding the PVB to the glass plate. The finishing process, typically performed at high temperature and high pressure, completes the bonding of the glass plate to each polymer intermediate layer. In the previous embodiment, the first glass plate may be a chemically strengthened glass plate, the second glass plate may be a non-chemically strengthened glass plate, and vice versa.

A thermoplastic material such as PVB may be applied as the preformed polymer intermediate layer. The thermoplastic layer can have a thickness of at least 0.125 mm (eg, 0.125, 0.25, 0.38, 0.5, 0.7, 0.76, 0.81, 1, 1.14, 1.19 or 1.2 mm) in certain embodiments. The thermoplastic layer can have a thickness of 1.6 mm or less (eg, 0.4 to 1.2 mm, such as about 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 or 1.2 mm). The thermoplastic layer can cover most, or preferably substantially all, of the two opposing main surfaces of the glass. The thermoplastic layer may also cover the edge of the glass. The glass plate in contact with the thermoplastic layer is at least 5 ° C or 10 ° C higher than the softening point of the thermoplastic material, for example, to facilitate the bonding of the thermoplastic material to the respective glass plate. It may be heated to a temperature higher than the softening point. The heating may be performed on the glass in contact with the thermoplastic layer under pressure.

The selected commercially available polymer interlayer materials are summarized in Table 1. This table also includes the glass transition temperature and modulus for each product sample. Use the DSC200 differential scanning calorimeter (Seiko Instruments Co., Ltd., Japan) for the glass transition temperature and elastic modulus data from the technical data available from the manufacturer, or for the glass transition temperature and elastic modulus, respectively. Or determined by the ASTM D638 method. Yet another description of the acrylic / silicone resin material used in the ISD resin is disclosed in US Pat. No. 5,64,763, and a description of the acoustically modified PVB resin is disclosed in JP-A-5-138840. All of their content is quoted here.

<tables num="1"><img id="000005" he="136" wi="158" file="JP5890518B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

One or more polymer interlayers may be incorporated into the composite laminated glass. Multiple intermediate layers will provide complementary or distinct functionality, including enhanced adhesion, acoustic control, UV transmission control, coloring, coloring and / or IR transmission control.

The elastic modulus of the polymer intermediate layer can range from about 1 MPa to 75 MPa (eg, about 1, 2, 5, 10, 15, 20, 25, 50 or 75 MPa). At a load rate of 1 Hz, the modulus of elasticity of a standard PVB intermediate layer can be about 15 MPa, and the modulus of elasticity of acoustic grade PVB can be about 2 MPa.

During the laminating process, the intermediate layer is generally heated to a temperature that is effective in softening the intermediate layer, which facilitates conformal mating of the intermediate layer to the respective surface of the glass plate. To. For PVB, the laminating temperature can be about 140 ° C. The mobile polymer chains in the interlayer material form bonds with the glass surface, which facilitates adhesion. High temperatures also accelerate the diffusion of residual air and / or moisture from the glass-polymer interface.

The application of pressure facilitates the flow of the interlayer material and suppresses the formation of bubbles that could otherwise be induced by the total vapor pressure of water and air trapped at the interface. Heat and pressure are applied simultaneously to the assembly in the autoclave to suppress the formation of bubbles.

Composite laminated glass can provide beneficial effects, including attenuation of acoustic noise, reduction of UV and / or IR light transmission, and / or a structure of aesthetic appeal of window openings. The individual glass plates that make up the disclosed laminated glass, as well as the laminated glass formed, have one or more attributes, including composition, density, thickness, surface shape measurements, as well as optical attenuation, sound attenuation, and impact resistance. It is characterized by a variety of properties, including mechanical properties such as. Various aspects of the disclosed composite laminated glass are described herein.

The composite laminated glass can be adapted for use, for example, as a window or glazing, and can be configured in any suitable size and size. In embodiments, laminated glass has independently varying lengths and widths from 10 cm to 1 m and above (eg, 0.1, 0.2, 0.5, 1, 2, or 5 m). Laminated glass is independently 0.1m²Super, for example 0.1, 0.2, 0.5, 1, 2, 5, 10, or 25m²Can have a super area.

Laminated glass can be substantially flat or molded for a particular application. For example, laminated glass can also be formed as a bent or molded part for use as a windshield or cover plate. The structure of the molded laminated glass may be simple or complex. In certain embodiments, the molded laminated glass may have a complex curvature, where the glass plates have separate radii of curvature in two independent directions. Therefore, in such a molded glass plate, the glass is bent along an axis parallel to a given dimension and also along an axis perpendicular to the same dimension, "crossing curvature". It may be characterized as having a "cross curvature". For example, an automobile sunroof is generally about 0.5 m x 1.0 m and has a radius of curvature of 2 to 2.5 m along the minor axis and a radius of curvature of 4 to 5 m along the main axis.

The molded laminated glass according to an embodiment can be defined by a bending factor, where the bending factor of a given part is equal to the radius of curvature along that axis divided by the length of the given axis. Therefore, for an exemplary automotive sunroof with radii of curvature of 2 m and 4 m along the respective axes of 0.5 m and 1.0 m, respectively, the bending factor along each axis is 4. Molded laminated glass can have bending coefficients ranging from 2 to 8 (eg, 2, 3, 4, 5, 6, 7, or 8).

An exemplary molded laminated glass 200 is shown in FIG. This molded laminated glass 200 is an outer (chemically strengthened) glass plate 1 formed on the convex surface of the laminated glass.<u style="single">1</u>On the other hand, the inner (non-chemically strengthened) glass plate 120 is formed on the concave surface of the laminated glass. However, it will be recognized that the convex surface of the unillustrated embodiment can include a non-chemically tempered glass plate, while the opposite concave surface can include a chemically strengthened glass plate.

Methods of bending and / or molding laminated glass can include gravity bending, press bending, and composite methods thereof. In the conventional method of gravity bending a thin flat glass plate into a curved shape such as an automobile windshield, one or more pre-cut glass at low temperature on the rigid preformed perimeter supporting surface of the bending equipment. Place the board. Bending equipment may be manufactured using metal or refractory materials. In the illustrated method, articulated bending equipment may be used. Prior to bending, the glass is typically supported only at a few contacts. The glass is usually heated by exposure to high temperatures in a slow-cooling kiln, which softens the glass and allows gravity to hang or drop the glass to match the surrounding supporting surface. Then, in general, substantially the entire supporting surface comes into contact with the perimeter of the glass.

A related technique is press bending in which a single flat glass plate is heated to a temperature substantially corresponding to the softening point of the glass. The heated plate is then pressed or molded to the desired curvature between the male and female mold members with complementary molding surfaces. The molded surface of the mold member may include a vacuum or air jet to engage the glass plate. In embodiments, the molded surface may be configured to be in contact with substantially the entire corresponding glass surface. Alternatively, one or both of the opposing molded surfaces may contact the respective glass surfaces over individual areas or at individual contacts. For example, the female mold member may be a ring-shaped surface. In embodiments, a combination of gravity bending and press bending techniques may be used.

The total thickness of the laminated glass can range from about 2 mm to 5 mm, where the externally chemically strengthened glass plate has a thickness of 1 mm or less (eg 0.5, 0.6, 0.7, 0.8, 0.9 or 1 mm, for example 0.5. Can have from 1 mm). In addition, the inner non-chemical tempered glass plate has a thickness of 2.5 mm or less (eg, 1, 1.5, 2 or 2.5 mm, eg, 1 to 2).<u style="single">.5</u>Can have mm). In embodiments, the total thickness of the glass plate in the laminated glass is less than 3.5 mm (eg, 3.5, 3, 2.5 or 2.3 mm).

An exemplary laminated glass structure is shown in Table 2, where GG refers to chemically strengthened aluminosilicate glass plates and the term "glass" refers to non-chemically strengthened soda lime (SL) glass plates. PVB refers to poly (vinyl butyral), which may be acoustic grade PVB (A-PVB), if desired. Example 1 ~<u style="single">12</u>Is the present invention, while Examples A and B are comparative examples.

<tables num="2"><img id="000006" he="123" wi="159" file="JP5890518B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

Applicants and others have shown that the laminated glass structures disclosed herein have excellent durability, impact resistance, toughness, and scratch resistance. As will be appreciated by those skilled in the art, the strength and mechanical impact performance of a glass plate or laminated glass is limited by defects in the glass, including both surface and internal defects. When the laminated glass is impacted, the impact point is in a compressed state, while the ring or "hoop" around the impact point, as well as the opposite side of the impacted plate, is in a tensile state. In general, the origin of breakage is a scratch on or near the point of maximum tension, usually on the glass surface. This will also occur on the opposite surface, but can occur within the ring. If the scratches in the glass become tense during an impact event, the scratches will probably propagate and the glass will generally break. Therefore, the magnitude and depth (layer depth) of the compressive stress are preferable.

One or both of the surfaces of the chemically strengthened glass plates used in the disclosed composite laminated glass are under compression for chemical strengthening. By providing compressive stress in the region near the surface of the glass, it is possible to prevent the propagation and breakage of cracks in the glass plate. Scratches propagate and damage occurs<u style="single">To</u>, Tensile stress from impact<u style="single">But</u>, The compressive stress of the surface must be exceeded at the tip of the scratch. In embodiments, the high compressive stress of the chemically strengthened glass plate and the depth of the large layers allow the use of thinner glass than in the case of non-chemically strengthened glass plates.

In the case of composite laminated glass, the laminated glass structure can bend much more than a thicker monolithic non-chemically tempered glass plate or a thicker non-chemically tempered laminated glass without breaking under mechanical impact. .. This additional deflection allows more energy transfer to the laminated glass interlayer, which can reduce the energy reaching the opposite side of the glass. As a result, the composite laminated glass disclosed herein can withstand higher impact energy than a monolithic non-chemically tempered glass plate or non-chemically tempered laminated glass of similar thickness.

In addition to its mechanical properties, laminated structures can be used to attenuate sound waves, as will be appreciated by those skilled in the art. The composite laminated glass disclosed herein can dramatically reduce acoustic transmission while using a thinner (lighter) structure with the mechanical properties required for many glazing applications.

The acoustic performance of laminates and glazing is generally affected by the bending vibrations of the glazing structure. Without being constrained by theory, human acoustic responses generally peak between 500 Hz and 5000 Hz, which corresponds to wavelengths of about 0.1-1 m in air and 1-10 m in glass. For glazing structures with a thickness of less than 0.01 m (&lt;10 mm), transmission is primarily due to the coupling of vibrations and sound waves to bending vibrations. Laminated glazing structures can be designed to convert energy from the glazing bending mode into shear strain in the polymer interlayer. In laminated glass utilizing thinner glass plates, the greater compliance of the thinner glass allows for greater amplitude, which in turn can impart greater shear strain to the intermediate layer. The low shear resistance of the most viscoelastic polymer interlayer material means that the interlayer promotes damping due to the high shear strain, which is converted to heat under the influence of molecular chain slip and relaxation.

In addition to the thickness of the laminated glass, the properties of the glass plates that make up the laminated glass will also affect the sound attenuation characteristics. For example, between a chemically tempered glass plate and a non-chemically tempered glass plate, there will be a small but important difference at the interface between the glass and the polymer intermediate layer that contributes to the greater shear strain in the polymer intermediate layer. Also, in addition to the obvious compositional differences, aluminosilicate glass and soda-lime glass will differ in physical and mechanical properties, including modulus of elasticity, Poisson's ratio, density, etc., which will result in different acoustic responses. ..

<p num="0061"> Traditional uniaxial strength tests, such as three-point or four-point bending tests, have been used to measure the strength of glass and ceramic materials. However, the interpretation of uniaxial strength test results can be challenging because the measured strength depends on the edge effect as well as the bulk material.</p><p num="0062"> On the other hand, biaxial bending tests can be used to provide strength assessments regardless of edge-induced phenomena. In the biaxial bending test, the laminated glass is supported at three or four points equidistant from the center and close to each other, and then the laminated glass is loaded at the center position. Therefore, it is convenient that the position of the maximum tensile stress occurs at the center of the surface of the laminated glass and is independent of the edge condition.</p><p num="0063"> A standard biaxial bending test (ECE R43 head test detailed in Annex 7/3) was performed on the exemplary flat laminated glass. Further, as described below, when the laminated glass (Sample 1) of the present invention was impacted on the non-chemically strengthened (soda lime) side, both glass plates were damaged. However, when the laminated glass of sample 1 was impacted on the chemically strengthened side, the non-chemically strengthened glass plate was damaged, but the chemically strengthened glass plate remained intact in 50% of the samples tested.</p><p num="0064"> In one test, a high load velocity impact is directed at the inner (non-chemically tempered) glass plate 120. In response, both the inner surface 124 of the inner glass plate 120 and the outer surface 112 of the outer glass plate 110 are placed in tension. Since the magnitude of the tensile stress on the outer surface 112 is greater than the tensile stress on the inner surface 124, in this configuration a milder tensile stress on the inner surface 124 is sufficient to damage the non-chemical tempered glass plate 120. On the other hand, the high tensile stress on the outer surface 112 is also sufficient to damage the chemically strengthened glass plate 110. The PVB interlayer deforms as the glass plate breaks, but prevents the head impact device from penetrating the laminated glass. This is a satisfactory response under ECE R43 head requirements.</p><p num="0065"> In related tests, the impact is instead directed to the outer (chemically tempered) glass plate 110. In response, the inner surface 114 of the outer glass plate 110 experiences a mild tensile stress and the outer surface 122 of the inner glass plate 120 experiences a greater stress. In this configuration, the large stress on the outer surface 122 of the inner non-chemically tempered glass plate 120 breaks the non-chemically tempered glass plate. However, the mild tensile stress of the inner surface 114 of the outer glass plate 110 may not be sufficient to overcome the compressive stress induced by ion exchange in the region near the surface of the chemically strengthened glass. In laboratory experiments, high load velocity impacts damaged the chemically strengthened glass plate 110 in only two of the six samples tested. In the remaining four samples, the non-chemically tempered glass plate 120 was damaged, but the chemically tempered glass plate 110 remained intact. All of the samples of the present invention exceeded the non-windshield impact requirements set forth in the ECE R43 Head Requirements.</p><p num="0066"> Biaxial bending tests were also performed on comparative samples A and B. Comparative sample A, which consists of a symmetrical structure of 1 mm thick chemically strengthened glass plate / 0.76 mm thick standard PVB / 1 mm thick chemically strengthened glass plate, shows no breakage, and therefore the laminated glass must break. Did fail the requirements of.</p><p num="0067"> Comparative sample B consists of a symmetrical structure of a 1.5 mm thick soda lime glass plate / 0.76 mm thick standard PVB / 1.5 mm thick soda lime glass plate. Both glass plates broke as a result of the biaxial bending test, and therefore Comparative Sample B passed the ECE R43 standard (Annex 7/3). However, both glass plates of the laminated glass of Comparative Sample B break regardless of which plate is impacted, thus providing a durable mechanical resistance to the external impact achieved on the composite laminated glass. could not. During the test, the recoil (ie, bounce) of the head was greater in Comparative Sample B than in Sample 1, and the comparative structure did not dissipate energy as effectively as in the examples of the present invention. I also found that it suggested.</p><p num="0068"> The Head Injury Criteria (HIC) is a conventional metric that can be used to assess the safety of laminated glass. The HIC value is a dimensionless quantity, which can be correlated with the likelihood of injury as a result of impact. Lower HIC values are desirable for internal impact events.</p><p num="0069"> For the illustrated flat laminated glass, the average HIC value for impact on the non-chemically reinforced side of 1.6 mm thick SL / 0.8 mm thick A-PVB / 0.7 mm thick GG laminate is 175, while The average HIC value for the impact on the chemically strengthened side of the 0.7 mm thick GG / 0.8 mm thick A-PVB / 1.6 mm thick SL laminate was 381. For automotive glazing applications, it is advantageous that the average HIC value for impact on the chemically strengthened side (outside) is greater than the average HIC value for impact on the non-chemically enhanced side. For example, the HIC value on the chemically enhanced side is 400 or more (for example, 400) so that the HIC value on the chemically enhanced side is at least 50 (for example, at least 50, 100, 150 or 200) higher than the HIC value on the non-chemically enhanced side. , 450 or 500 or more), and the HIC value on the non-chemically fortified side can be 400 or less (eg, 400, 350, 300, 250, 200, 150 or 100) or less.</p><p num="0070"> As used here, the singular contains multiple objects unless the context explicitly indicates otherwise. Thus, for example, references to "metals" include examples of having more than one such "metal" unless the context explicitly indicates otherwise.</p><p num="0071"> The range can be expressed here as "about" from one particular value and / or "about" another particular value. When such a range is represented, the example includes from that one particular value and / or to another particular value. Similarly, it will be understood that certain values form another aspect when the values are expressed as approximations using the antecedent "about". It will be further understood that each endpoint of the range is significant both with respect to the other endpoints and regardless of the other endpoints.</p><p num="0072"> Unless otherwise stated, none of the methods described herein is intended to be considered as requiring the steps to be performed in a particular order. Therefore, the claims of the method do not actually enumerate the order in which the steps follow, or specifically state in the claims or description in other forms that the steps should be restricted to a particular order. If not, it is never intended to infer any particular order.</p><p num="0073"> It is also noted that the enumeration herein refers to components of the invention that are "configured" or "adapted" to function in a particular manner. In this regard, such components are "constructed" or "adapted" to embody certain properties or to be possible in a particular manner, as such. An enumeration is a structural enumeration rather than an enumeration of intended use. More specifically, the enumeration here in the form in which a component is "constituent" or "adapted" means the existing physical condition of that component and therefore the structure of that component. It should be interpreted as a clear enumeration of features.</p><p num="0074"> It will be apparent to those skilled in the art that various modifications and alterations can be made to the invention without departing from the spirit and scope of the invention. Modifications, combinations, subordinate combinations and modifications of the disclosed embodiments including the spirit and essence of the present invention will be recalled to those skilled in the art, and thus the present invention is the scope of the accompanying claims and their equivalents. It should be considered to include everything within the scope of.</p>

100 laminated glass 110 outer glass plate 120 inner glass plate 130 polymer intermediate layer 200 molded laminated glass