Cold formability analysis of glass laminate products using stress prediction and related methods

Abstract

The present application relates to cold forming properties of glass laminate products using stress prediction analysis and related methods. Products and cold forming methods of glass laminate products using stress prediction analysis are provided. Based on multiple geometric parameters of the glass layers of the glass laminate product, a cold forming estimate (CFE) value is calculated, which is related to the stress experienced by the glass sheets of the glass laminate during the cold forming process. The calculated CFE value is compared with a cold forming threshold, which is related to the possibility of defects forming in the complex curved glass laminate product during the cold forming process. A cold-formed glass laminate product having geometric parameters such that the CFE value is lower than the cold forming threshold is also provided.

Description

[0001] This invention patent application is a divisional application of the invention patent application with international application number PCT / US2018 / 054690, international application date October 5, 2018, application number 201880065279.8 entering the Chinese national phase, and invention name “Analysis of cold formability of glass laminate products using stress prediction and related methods”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority under 35 U.S.C. §119 to U.S. Provisional Application Serial No. 62 / 568,915, filed on October 6, 2017, which is based upon and incorporated herein by reference in its entirety. Background Art

[0004] The present disclosure relates to cold-formed glass laminate articles, and more particularly, to articles and methods of cold-forming glass laminate articles using stress prediction analysis. In specific embodiments, such articles can be used in transportation applications (e.g., automotive glazing) and architectural applications.

[0005] Curved laminates are used in a variety of applications, including automotive glazing and architectural windows. For such applications, sheets of glass are precisely bent to define a shape and / or curvature that is determined by the configuration and size of the opening in which the glass is to be installed, as well as the type of vehicle or architectural aesthetics. Such curved laminates are typically made by heating a flat sheet of glass to a suitable temperature for forming, applying a force to the sheet to change the shape, and then laminating two curved sheets together. This process is often referred to as a "hot bending" process. Summary of the invention

[0006] A first aspect of the present disclosure pertains to a method for evaluating the cold formability of a complex curved glass laminate product comprising a first glass sheet and a second glass sheet. The method comprises: obtaining a first geometric parameter (G1) and a second geometric parameter (G2) of a complex curved first glass sheet of the glass laminate product. The method comprises: calculating a cold forming estimate (CFE) value associated with the stress experienced by the first glass sheet during the cold forming process. The CFE value comprises B1*G1+B2*G2, wherein B1 and B2 are coefficients calculated to associate G1 and G2 with the CFE value. The method comprises comparing the calculated CFE value with a cold forming threshold value, which is associated with the likelihood of defects forming in the complex curved glass laminate product during the cold forming process.

[0007] The second aspect of the present disclosure pertains to a method for cold forming a complexly curved glass laminate article. The method includes supporting a first glass sheet, and the first glass material sheet has a complexly curved shape, a first major surface, and a second major surface. The method includes supporting a second glass sheet on the first glass sheet, and the second glass sheet has a first major surface, a second major surface, and a shape different from the complexly curved shape. The method includes placing a polymeric interlayer material between the second major surface of the first glass sheet and the first major surface of the second glass sheet. The method includes bending the second glass material sheet to conform to the complexly curved shape of the first glass material sheet. During the bending process, the maximum temperature of the first glass sheet is less than the glass transition temperature of the glass material of the first glass sheet, and the maximum temperature of the second glass sheet is less than the glass transition temperature of the glass material of the second glass sheet. The complexly curved shape has a first geometric parameter (G1) and a second geometric parameter (G2), and during the bending process, the first principal stress of the first glass sheet is less than or equal to the estimated stress value of (B1*G1 + B2*G2), where B1 and B2 are coefficients determined for correlating G1 and G2 with the stress experienced by the first glass sheet during the bending process.

[0008] Another aspect of the present disclosure pertains to a cold formed glass laminate article. The glass laminate article includes a first glass layer and a second glass layer. The first glass layer includes: an inner surface, an outer surface opposite the inner surface, a width W, a length L, and a complexly curved shape having a chord height CH, where -0.14 < L / W - 0.05*(CH) < 0.223. The second glass layer includes an inner surface and an outer surface. The glass laminate article includes a polymeric interlayer disposed between the inner surface of the first glass layer and the inner surface of the second glass layer.

[0009] Another aspect of the present disclosure pertains to a cold formed glass laminate article. The glass laminate article includes a first glass layer and a second glass layer. The first glass layer includes: an inner surface, an outer surface opposite the inner surface, a width W, a length L, and an average thickness T1. The first glass layer includes a complexly curved shape having: a chord height CH, a depth of bend (DOB), a minimum first radius of curvature R1, a second minimum radius of curvature R2, and a maximum Gaussian curvature GC. The second glass layer includes an inner surface, an outer surface, and an average thickness T2. The glass laminate article includes an interlayer disposed between the inner surface of the first glass layer and the inner surface of the second glass layer. The dimensions of the glass laminate article are such that: (0.05673*W - 0.1035*L - 0.0031*CH + 6.99003*CH + 0.1855*R1 + 0.00115*R2 + 4.633988*GC - 0.1836*T1 - 101.95*T2) is less than 80 MPa.

[0010] Other features and advantages of the present invention are set forth in the following detailed description, some of which will be readily apparent to those skilled in the art from the description or recognized by practicing the various embodiments described herein, including the following detailed description, claims, and accompanying drawings.

[0011] It is to be understood that the above general description and the following detailed description are merely exemplary and are intended to provide an overall review or framework for understanding the nature and character of the claims. The accompanying drawings provide a further understanding and are incorporated into and constitute a part of this specification. The drawings illustrate one or more embodiments and together with the description serve to explain the principles and operation of the various embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a cross-sectional view of a flat glass layer, a curved glass layer, and an intervening film layer prior to forming according to an exemplary embodiment.

[0013] Figure 2 According to an exemplary embodiment, Figure 1 A cross-sectional view of a glass laminate article showing layers formed into a curved shape.

[0014] Figure 3 is a perspective view of a glass laminate article formed into a windshield according to an exemplary embodiment.

[0015] Figure 4 yes Figure 3 A top plan view of a glass laminate product.

[0016] Figure 5 is a perspective view of a glass laminate article formed into a ceiling panel according to an exemplary embodiment.

[0017] Figure 6 yes Figure 5 A top plan view of a glass laminate product.

[0018] Figure 7 is a perspective view of a glass laminate article formed into a side window according to an exemplary embodiment.

[0019] Figure 8 yes Figure 7 A top plan view of a glass laminate product.

[0020] Fig. 9 A process for evaluating the cold formability of a complex curved glass laminate article is shown according to an exemplary embodiment.

[0021] Fig.10A comparison of CFE values ​​calculated using Equation 3 relative to corresponding FEA calculated stress values ​​is shown for 29 different designs of glass laminate articles 50 .

[0022] Fig.11A and 11B yes Fig.10 2D plot of the data showing the relationship between selected geometric parameters and the cold forming threshold.

[0023] Figures 12A-12C Designed for windshields Fig.10 2D plot of data for a glass laminate product.

[0024] Figures 13A-13C Designed for ceilings Fig.10 2D plot of data for a glass laminate product.

[0025] Figures 14A-14C Designed for use in side windows (e.g. sidelights) Fig.10 2D plot of data for a glass laminate product.

[0026] Fig.15 A vehicle equipped with one or more of the glass laminate articles discussed herein. DETAILED DESCRIPTION

[0027] Referring generally to the accompanying drawings, various methods are directed to cold forming of complex curved glass laminate articles. In general, applicants have determined that the stress experienced by one or more of the glass layers of a glass laminate during the cold bending process (e.g., the first principal stress) is a good indicator of the likelihood of defects forming during the cold bending process. For example, applicants have found that if the cold bending stress experienced during the cold bending process is too high, defects such as wrinkling or cracking may occur. However, standard processes for accurately calculating the stresses that a glass laminate article will experience during the cold bending process (e.g., finite element analysis) are complex and require significant amounts of computing time and energy.

[0028] Thus, the present application relates to a process for determining the cold formability of a glass laminate article by calculating a Cold Forming Estimator (CFE) value, which is related to the stress that the glass sheet is expected to experience during the cold forming process. The CFE value is then compared to a cold forming threshold value, which is related to the likelihood that defects will form in a complex curved glass laminate article during the cold forming process. The CFE value is based on the sum of at least two geometric parameters that are indicative of the geometric morphology of the glass laminate article, each multiplied by a statistically calculated coefficient. The cold forming threshold value can be determined by testing different laminate structures to determine a threshold value related to the maximum acceptable stress that the glass laminate article can experience during the cold bending process without forming an undesirable level of defects.

[0029] Using the methods discussed above, once the CFE coefficients are determined and the cold forming thresholds are determined, defect formation during cold forming can be accurately predicted simply by calculating the CFE values ​​based on easily measurable geometric parameters of the glass laminate article. Thus, the methods discussed herein eliminate the need to run complex mathematical analyses (e.g., finite element analysis) or perform prototyping / testing to determine whether a new complex curved glass laminate article design can be cold formed without unacceptable defect formation. Thus, in this manner, the process of cold forming a new complex curved glass laminate article can be simplified.

[0030] See also Figure 1 and Figure 2 , showing a cold-formed glass laminate article and forming process according to an exemplary embodiment. Figure 1 As shown, the laminate stack 10 includes a first glass layer 12 having a complex curved shape. The first glass layer 12 includes: an outer surface 14, which includes at least one section having a convex shape; and an inner surface 16, which is opposite to the outer surface 14 and includes at least one section having a concave shape. A thickness is defined between the outer surface 14 and the inner surface 16, such as an average thickness T1.

[0031] Laminate stack 10 also includes a second glass layer 20. Glass layer 20 includes an outer surface 22 and an inner surface 24 opposite outer surface 22. A thickness, such as an average thickness T2, is defined between outer surface 22 and inner surface 24. In some embodiments, glass layer 20 is thinner than glass layer 12, such that T1>T2; and in specific embodiments, the glass material composition of glass layer 12 is different from the glass material composition of glass layer 20. In various embodiments, T1 is at least 2.5 times greater than T2, and in other embodiments, T2 is at least 2.5 times greater than T1. In specific embodiments, T1 is 1.5 mm to 4 mm, while T2 is 0.3 mm to 1 mm, and in even more specific embodiments, T2 is less than 0.6 mm. In specific embodiments, T1 is 1.6 mm and T2 is .55 mm; T1 is 2.1 mm and T2 is .55 mm; T1 is 2.1 mm and T2 is 0.7 mm; T1 is 2.1 mm and T2 is 0.5 mm; T1 is 2.5 mm and T2 is 0.7 mm.

[0032] Laminate stack 10 includes an interlayer 30 positioned between first glass layer 12 and second glass layer 20. In this arrangement, interlayer 30 is positioned between inner surface 16 of first glass layer 12 and inner surface 24 of second glass layer 20. In particular embodiments, interlayer 30 is secured to at least one of inner surface 16 of first glass layer 12 and inner surface 24 of second glass layer 20 and serves to hold laminate 50 together after formation (e.g., Figure 2 The intermediate layer 30 may be a polymer intermediate layer, such as a polyvinyl butyral layer.

[0033] Figure 1 showing a cross-sectional view of the laminate stack 10 prior to cold forming, and Figure 2 A glass laminate article (laminate 50) is shown formed from laminate stack 10 via cold forming. Figure 1 As shown, the first glass layer 12 is supported (eg, on a frame), and the second glass layer 20 is placed supported on the first glass layer 12. A polymer interlayer 30 is placed between the first glass layer 12 and the second glass layer 20.

[0034] like Figure 1 As shown, before the cold forming process begins, the first glass layer 12 is formed into a curved shape, while the second glass layer 20 is flat before the forming process. Figure 1During the cold forming process of FIG. 1 , pressure (shown as arrow P) is applied to the stack, thereby pressing the second glass layer 20, the interlayer 30, and the first glass layer 12 together. Under the pressure P, the second glass layer 20 is deformed to have the curved shape of the first glass layer 12, and once the second glass layer 20 is formed to match the shape of the first glass layer 12, the first glass layer 12 and the second glass layer 20 are bonded together by the interlayer 30 to form a stack as shown in FIG. Figure 2 A complex curved article 50 is shown.

[0035] from Figure 2 It can be seen that after forming, the second glass layer 20 also has a curved shape, so that the outer surface 22 includes at least one section having a concave shape, and the inner surface 24 includes at least one section having a convex shape. The forming process shown ensures that the shape and curvature of the second glass layer 20 closely matches the shape and curvature of the first glass layer 12. Thus, in this arrangement, the second glass layer 20 is bent into a complex curved shape that conforms to the first glass layer 12 by the pressure P without raising the temperature above the glass transition temperature of the glass material of the second glass layer 20 and / or the glass material of the first glass layer 12.

[0036] In various embodiments, the forming pressure represented by arrow P may be about 1 atmosphere or greater. The forming pressure may be air pressure and / or pressure applied by a press or die.

[0037] In various embodiments, the first glass layer 12 is formed into its complex curved shape via a hot forming process and then cooled prior to a cold forming process, such as Figure 1 In a specific embodiment, the thermoforming of the first glass layer 12 may include heating it to a temperature close to the softening point of the glass material of the first glass layer 12 and then bending it into a complex curved shape.

[0038] exist Figure 1 During the forming process shown, the complex curved first glass layer 12 and the flat second glass layer 20 are cold formed into a curved laminate 50 at a temperature well below the softening point of the glass material of the second glass layer 20 and / or the glass material of the first glass layer 12. In various embodiments, Figure 1The cold forming process occurs at a temperature that is 200 degrees Celsius or more lower than the softening point of the glass material of the second glass layer 20 and / or the glass material of the first glass layer 12. The softening point refers to the temperature at which the glass deforms under its own weight. In one or more specific embodiments, the temperature during the cold forming process is less than about 400 degrees Celsius, less than about 350 degrees Celsius, or less than about 300 degrees Celsius. In a specific embodiment, the cold forming process is room temperature to about 140 degrees Celsius. Room temperature can be considered to be the ambient temperature of the production floor (e.g., 16 degrees Celsius to about 35 degrees Celsius).

[0039] like Figure 1 As shown, during cold forming, the interlayer 30 is located between the glass layers 12 and 20. In some such embodiments, the interlayer 30 serves to bond the glass layers 12 and 20 together before or during cold forming. In some such embodiments, during the application of the pressure P, the stack 10 is heated to a temperature of about 100 degrees Celsius to about 140 degrees Celsius, thereby forming a bond between the interlayer 30 and the glass layers 12 and 20.

[0040] like Figure 3-8 As shown, in various embodiments, the stack 50 is formed into various complex curved shapes, thereby showing various geometric parameters that can be used to determine the CFE value. Figure 3-8 As shown, the geometric parameters of the first glass layer 12 that can be used to calculate the CFE value may include: width W, length L, chord height CH, bend depth (DOB), minimum first radius of curvature R1, second minimum radius of curvature R2, and maximum Gaussian curvature GC. In a specific embodiment, the determination of the CFE value may also include additional geometric parameters, such as the thickness T1 of the first glass layer 12 and the thickness T2 of the second glass layer 20.

[0041] like Figure 3-8 As shown, the glass laminate article 50 can be formed into various shapes for a wide variety of applications. For example, Figure 3-4 A glass laminate article 50 is shown that is formed to form an automotive windshield, according to an exemplary embodiment. Figure 5-6 A glass laminate article 50 is shown that is formed to form an automotive ceiling / visor / moon roof according to an exemplary embodiment. Figure 7-8 A glass laminate article 50 is shown that is shaped to form an automotive side window (eg, a sidelight) according to an exemplary embodiment.

[0042] from Figure 3-8As can be seen, it may be desirable to form the glass laminate article 50 into a wide variety of complex curved shapes that may be required for a particular application, vehicle body design, etc. Typically, to determine whether a particular glass laminate article design is suitable for cold forming, a complex and computationally intensive finite element analysis (FEA) would be required to determine whether the stresses in the glass layers during the cold bending process would be too high and thus cause defects. Due to the large number of potential article shapes and designs and the need to produce them quickly, Applicants have developed a method for predicting whether and when a glass laminate article shape should be cold formed using relatively simple calculations that do not rely on FEA or other computer modeling techniques.

[0043] also, Figure 3-8 shows different geometric parameters that can be used to calculate the CFE values ​​as discussed herein. Figure 3-8 As shown, the glass laminate product 50 (or one of the glass layers of the product 50) includes: a width W, a length L, a chord height CH, a depth of bend (DOB), a minimum first radius of curvature R1, a second minimum radius of curvature R2, and a maximum Gaussian curvature GC. Figure 1 As shown, the glass layers 12 and 20 also have average thicknesses T1 and T2. In the specific embodiments discussed herein, these dimensions are defined as follows: width WI is the width of the smallest bounding box containing the glass laminate article 50; length L1 is the length of the smallest bounding box containing the glass laminate article 50; bend depth DOB is the maximum depth of the glass laminate article 50 from the projection plane; chord height CH is the maximum perpendicular distance between the arc of the glass surface of the glass laminate article 50 and the centerline chord; the minimum first radius of curvature R1 is the minimum radius along the first bend curvature direction; the second minimum radius of curvature R2 is the minimum radius along the cross bending curvature direction; Gaussian curvature is the product of the principal curvatures at a point, where the principal curvatures are the minimum and maximum normal curvatures at a point, and the normal curvature is the curvature on the surface lying on the plane containing the tangent vector at a given point.

[0044] As discussed in more detail below, various combinations of these geometric parameters are used for various CFE values.

[0045] In general, see Fig. 9, the present disclosure provides a method 100 for evaluating the cold formability of a complex curved glass laminate article (e.g., article 50). In step 102, a plurality of geometric parameters of a complex curved first glass sheet of the glass laminate article are obtained, such as a first geometric parameter (G1) and a second geometric parameter (G2). As discussed below, in various embodiments, more than two geometric parameters may be used in the cold formability evaluation method discussed herein. In step 104, a cold forming estimate (CFE) value related to the stress experienced by the first glass sheet during the cold forming process is calculated. In step 106, the calculated CFE value is compared with a cold forming threshold value, which is related to the likelihood of defects being formed in the complex curved glass laminate article during the cold forming process.

[0046] Generally speaking, the comparison of step 106 is then used to determine whether the specific design of the complex curved article 50 is suitable for cold forming. In a specific embodiment, if the CFE value is less than the cold forming threshold, a cold forming method is performed, such as described above with respect to Figure 1 Because of the correlations discussed herein between the various CFE values ​​and the first principal stress experienced by the first glass layer during cold forming, when cold forming is performed on a glass laminate article having a CFE value less than the cold forming threshold, stresses within the glass laminate article 50 remain at defect-causing levels during the cold forming process.

[0047] Generally speaking, the CFE value is the sum of two or more geometric parameters associated with the glass laminate article 50 (multiplied by the calculated coefficients discussed herein), which applicants have determined provide a high level of correlation with the stresses experienced during cold forming. Therefore, by calculating the CFE value as discussed herein, the cold formability of a particular glass laminate design can be determined without the need to perform FEA on the particular design or to prototype and test the particular design. Therefore, while the CFE value can be calculated in a variety of ways as discussed herein, in one embodiment, the CFE value is B1*G1+B2*G2, where B1 and B2 are coefficients calculated using statistical methods that relate G1 and G2 to glass laminate articles suitable for cold forming.

[0048] Generally speaking, the coefficients B1 and B2 (as well as the coefficients of any other geometric parameters that may be used to calculate the CFE value) are determined by a multivariate linear regression analysis of the FEA determined stresses for a plurality of complex curved glass laminate articles. Thus, by performing a linear regression analysis of a data set of FEA determined stresses for a plurality of complex curved articles, the effect or correlation of G1 and G2 (as well as other geometric parameters discussed below) on the stresses experienced during cold forming can be determined. This analysis provides numerical values ​​for the coefficients B1 and B2 to be determined. Once B1 and B2 (as well as the coefficients of any other geometric parameters that may be used to calculate the CFE value) are determined, the CFE value can be calculated as the sum of the desired set of geometric parameters multiplied by the coefficients without the need to run an FEA for each new design evaluation.

[0049] Applicants believe that the coefficients (e.g., B1 and B2) are a function of the glass material of the first glass layer 12 and the second glass layer 20. Therefore, for the material type of the glass layers of a particular glass laminate article, B1 and B2 (as well as the coefficients of any other geometric parameters that can be used to calculate CFE values) can be determined by linear regression analysis and can then be used to calculate CFE values ​​for different sizes, shapes, curvatures, etc. of different laminate designs without the need to perform FEA for each new design.

[0050] In addition, it is believed that the cold forming threshold is also a function of the glass material of the first glass layer 12 and the second glass layer 20. In various embodiments, the cold forming threshold is related to the maximum allowable stress that the first glass layer 12 can withstand without forming defects. In a specific embodiment, the cold forming threshold is determined by evaluating the presence or absence of defects in laminated test samples of various sizes and shapes, and then correlating the presence or absence of defects with the expected stress level during cold bending calculated using finite element analysis or measured. In addition, the applicant believes that the cold forming threshold is a function of the material strength of the layers 12 and 20.

[0051] In a specific embodiment, the first geometric parameter G1 is L / W, the second geometric parameter G2 is the chord height CH, B1 is 1 and B2=0.5. Therefore, in such an embodiment, the CFE value is determined as follows:

[0052] Equation 1: CFE = (L / W + 0.5CH)

[0053] When the value of Equation 1 is less than the determined cold-forming threshold, it is determined that the glass laminate article having L, W, and CH is cold-formable. In a specific embodiment, when -0.14 < (L / W + 0.5CH) < 0.223, it is determined that the glass article having L, W, and CH is cold-formable, and in such embodiments, a laminated glass article 50 can be formed having a shape and dimensions such that -0.14 < L / W - 0.05*(CH) < 0.223. In some such embodiments, the first glass layer 12 is formed of a soda-lime glass material, and the second glass layer 20 is formed of an alkaline aluminosilicate glass composition or an alkaline aluminoborosilicate glass composition.

[0054] In another specific embodiment, G1 = chord height CH, G2 = maximum Gaussian curvature GC, B1 = 1, and B2 = 1. Thus, in such embodiments, CFE = (CH + GC), and when this value is less than the determined cold-forming threshold, it is determined that the glass article having GC and CH is cold-formable. In a specific embodiment, when 8 < (GC + CH) < 20, it is determined that the glass article having GC and CH is cold-formable. In some such embodiments, the first glass layer 12 is formed of a soda-lime glass material, and the second glass layer 20 is formed of an alkaline aluminosilicate glass composition or an alkaline aluminoborosilicate glass composition.

[0055] In another specific embodiment, the first glass layer 12 includes: width W, length L, chord height CH, depth of bend (DOB), minimum first radius of curvature R1, second minimum radius of curvature R2, average thickness T1, and maximum Gaussian curvature GC. Additionally, the second glass layer 20 includes thickness T2. In such embodiments, the CFE value is a predicted stress value, and it is determined as follows:

[0056] Equation 2: CFE = B0 + B1*W + B2*L + B3*DOB + B4*CH + B5*R1 + B6*R2 + B7*GC + B8*T1 + B9*T2)

[0057] In this embodiment, the units of these 9 geometric parameters are as follows: W (mm), L (mm), DOB (mm), CH (mm), R1 (mm), R2 (mm), maximum GC (10 -7 )(1 / mm 2 )、T1 (mm) and T2 (mm). The constant coefficients B0 - B9 for each geometric parameter are determined from an FEA data set of glass laminate articles 50 having different geometric parameters but formed of the same material.

[0058] In a specific embodiment, B0-B9 were calculated from a data set of FEA determined stresses for 29 different glass laminate article designs and are shown in Table 1.

[0059] Table 1

[0060]

[0061] Using this data, Equation 2 becomes:

[0062] Equation 3: CFE = 0.05673*W-0.1035*L-0.0031*DOB+6.99003*CH+0.01855*R1+0.00115*R2+4.633988*GC-0.1836*T1-101.95*T2

[0063] Then, for a given glass laminate article 50 design, the value of Equation 3 is then compared to the cold forming threshold to determine cold formability. In a specific embodiment, using this equation, the cold forming threshold is 80 MPa, 50 MPa, or 20 MPa. Therefore, in such embodiments, the laminate glass article 50 is formed to have a shape and size such that (0.05673*W-0.1035*L-0.0031*DOB+6.99003*CH+0.01855*R1+0.00115*R2+4.633988*GC-0.1836*T1-101.95*T2)<80 MPa.

[0064] It will be appreciated that in this embodiment, W, L, CH, DOB, R1, R2, T1, and GC are all geometric parameters of the first layer 12, while T2 is a geometric parameter of the second glass layer 20. As described above, linear regression analysis is employed to determine the coefficients shown in Equation 3. In some such embodiments, the first glass layer 12 is formed from a soda-lime glass material, and the second glass layer 20 is formed from an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition.

[0065] In a specific embodiment, the first glass layer 12 is formed of an unstrengthened glass sheet, and the cold forming threshold is determined to be 20 MPa. In this embodiment, the CFE value is a predicted stress value and is obtained by Equation 3. In such an embodiment, the prediction method of cold formability includes: when the calculated CFE value of Equation 30 is less than 20 MPa, determining that the specific design of the glass laminate article 50 is suitable for cold forming.

[0066] In another specific embodiment, the first glass layer 12 is formed of a strengthened glass sheet (e.g., a heat-strengthened glass material, a chemically strengthened glass sheet, etc.), and the cold forming threshold is determined to be 50 MPa. In this embodiment, the CFE value is a predicted stress value and is obtained by Equation 3. In such an embodiment, the prediction method of cold formability includes: when the calculated CFE value of Equation 3 is less than 50 MPa, determining that the specific design of the glass laminate article 50 is suitable for cold forming.

[0067] In various embodiments, the first glass layer 12 is formed of a soda-lime glass material, and the second glass layer 20 is formed of an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition. In some such embodiments, the glass layer 20 is chemically strengthened by ion exchange. In some embodiments, the first glass layer 12 may be annealed. In some embodiments, both layers 12 and 20 are formed of soda-lime glass. In other embodiments, both layers 12 and 20 are formed of an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition.

[0068] In various embodiments, W is 300 mm to 1800 mm, L is 230 mm to 1600 mm, CH is 1 mm to 45 mm, DOB is 5 mm to 210 mm, R1 is 40 mm to 5000 mm, R2 is 740 mm to 32500 mm, and GC is 0.14e-7 1 / mm 2 Up to 15e-7 1 / mm 2 , T1 is 1mm to 4mm, and T2 is .3mm to 1mm.

[0069] To provide other examples, Figure 10-14C The data graph shown shows the relationship between various CFE values ​​and various cold forming thresholds. Fig.10 The CFE values ​​calculated using Equation 3 are shown relative to the designed FEA calculated stresses for 29 different designs of glass laminate articles 50. Fig.10 It can be seen that when the CFE value calculated using Equation 3 is lower than the cold forming threshold 120, the stress determined by FEA is also lower than the cold forming threshold 120 for a particular glass product design, and this relationship indicates that the product can be cold formed. In this embodiment, the cold forming threshold 120 is 20 MPa.

[0070] like Fig.10 As shown, an upper limit of the cold forming threshold 130 can also be determined. Fig.10It can be seen that when the CFE value calculated using Equation 3 is above the cold forming threshold 130, the FEA determined stress for the specific glass product design is also above the cold forming threshold 130, and this indicates that the product is not cold formable. If the CFE value calculated using Equation 3 is between the threshold 120 and the threshold 130, there is a low correlation between the calculated CFE value and the FEA stress value, and therefore within this range, the FEA stress should be calculated to determine whether the specific glass laminate design within this range is cold formable because the predicted value of the CFE value is low. In a specific embodiment, the threshold 130 is the B10 value of the material of the first glass layer 12 (in the specific embodiment shown, soda lime glass) based on the Weibull distribution, and the threshold 120 is determined to be below this threshold with an acceptably low probability of forming a wrinkled layer 20. Explained, during the cold forming process, stresses are accumulated on two layers of the glass laminate product. Typically, the strength of one layer (e.g., the soda lime glass layer) is much lower than that of another layer (e.g., the chemically strengthened layer). Therefore, the weaker one is used to determine the strength threshold during bending.

[0071] Fig.11A and 11B yes Fig.10 2D plot of the data showing the relationship between selected geometric parameters and the cold forming thresholds 120 and 130. Fig.11A is a 2D map generated using the maximum GC and chord height, and Fig. 11B is a 2D map generated using chord height CH and L / W. By using cold forming thresholds of 120 and 130, respectively Fig.11A and 11B Both maps in are divided into 3 regions. With some exceptions, most of the data points are within the desired regions. Fig.11A A clear correlation between these two parameters (maximum GC and CH) is shown: when the chord height increases, the maximum GC should be reduced to ensure that the laminated article is cold formable. Similarly, Fig. 11B A clear correlation between these two parameters (L / W and chord height CH) is shown: when the chord height increases, the L / W needs to increase in order to make the glass laminate article cold formable.

[0072] Figures 12A-12C Designed for windshields Fig.10 2D image of a glass laminate product. Fig. 12B As shown, the L / W values ​​of the windshield design are mainly distributed in the range of 0-0.8. The windshield data has cold forming thresholds of 120 and 130, which are similar to the maximum GC-chord height diagram ( Fig.11A ) and L / W-chord height diagram ( Fig. 11B ) in the overall data.

[0073] Figures 13A-13C Designed for ceilings Fig.10 2D image of a glass laminate product. Fig. 13B As shown, the L / W value is mainly distributed in the range of 0-1.0. As shown, compared with the overall data ( Fig.11A and 11B ), the ceiling data has a wider area between thresholds 120 and 130.

[0074] Figures 14A-14C Designed for use in side windows (e.g. sidelights) Fig.10 2D image of a glass laminate product. Fig. 14B As shown, the L / W value is mainly distributed in the range of 0-0.7.

[0075] See also Fig.15 , showing the use of the glass laminate article 50 as part of a vehicle window, ceiling, or side window. As shown, the vehicle 200 includes one or more side windows 202, a ceiling 204, a rear window 206, and / or a windshield 208. Generally speaking, any of the embodiments of the glass laminate article 50 discussed herein can be used for one or more side windows 202, ceiling 204, rear window 206, and / or windshield 208. Generally speaking, one or more side windows 202, ceiling 204, rear window 206, and / or windshield 208 are supported within an opening defined by a vehicle frame or body 210 such that the outer surface 22 (see FIG. 21 ) of the second glass layer 20 is substantially parallel to the outer surface of the vehicle frame or body 210. Figure 1 ) faces toward the vehicle interior 212. In this arrangement, the outer surface 14 (see Figure 1 ) faces toward the exterior of the vehicle 200 and may define the outermost surface of the vehicle 200 at the location of the glass article. As used herein, vehicles may include: vehicles, locomotives, trains, boats, ships, airplanes, helicopters, drones, and spacecraft, among others. In other embodiments, the glass laminate article 50 may be used in various other applications where a thin, curved glass laminate article may be advantageous, such as for architectural glass, building glass, and the like.

[0076] As used herein, "complex bends" or "complex curved" refer to non-flat shapes that have curvatures along two mutually different orthogonal axes. Examples of complex curved shapes include shapes with simple or compound curvatures, also known as non-developable shapes, including but not limited to spherical, non-spherical and annular shapes. The complex curved stack according to an embodiment may also include segments or portions of such surfaces, or may include a combination of such bends and surfaces. In one or more embodiments, the stack may have a compound bend including a major radius and a cross curvature. According to an embodiment, the complex curved stack may have different radii of curvature in two independent directions. Therefore, according to one or more embodiments, the complex curved stack may be characterized as having a "cross curvature", wherein the stack is curved along an axis (i.e., a first axis) parallel to a given scale, and is also curved along an axis (i.e., a second axis) perpendicular to the same scale. The curvature of the stack may be even more complex when an apparent minimum radius is combined with an apparent cross curvature and / or a bending depth.

[0077] Some stacks may also include bends along axes that are not perpendicular to each other. As a non-limiting example, a complex curved stack may have a length and width dimension of 0.5m by 1.0m, and a radius of curvature of 2 to 2.5m along the secondary axis and a radius of curvature of 4 to 5m along the primary axis. In one or more embodiments, the complex curved stack may have a radius of curvature of 5m or less along at least one axis. In one or more embodiments, the complex curved stack may have a radius of curvature of 5m or less at least along a first axis and along a second axis perpendicular to the first axis. In one or more embodiments, the complex curved stack may have a radius of curvature of 5m or less at least along a first axis and along a second axis that is not perpendicular to the first axis.

[0078] Glass layers 12 and / or 20 may be formed from a variety of materials. In a specific embodiment, glass layer 20 is formed from a chemically strengthened alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition, and glass layer 12 is formed from a soda lime glass (SLG) composition. In a specific embodiment, glass layers 12 and / or 20 are formed from a chemically strengthened material, such as an alkali aluminosilicate glass material or an alkali aluminoborosilicate glass composition, having a chemically strengthened compressive layer having a depth of compression (DOC) of about 30 μm to about 90 μm, and a compressive stress of 300 MPa to 1000 MPa on at least one major surface of the sheet. In some embodiments, the chemically strengthened glass is strengthened by ion exchange.

[0079] Examples and properties of glass materials

[0080] In various embodiments, the glass layer 12 and / or 20 can be formed from a variety of arbitrary glass compositions. Examples of glass that can be used for the glass layer 12 and / or 20 described herein can include: a soda-lime silicate glass composition, an aluminosilicate glass composition, an alkali aluminosilicate glass composition, or an alkali aluminoborosilicate glass composition, but other glass compositions are also considered. In one or more embodiments, a suitable glass composition can be characterized as ion-exchangeable. As used herein, "ion-exchangeable" means that the composition contained in the layer is capable of achieving an exchange of cations of the same valence state with cations located at or near the surface of the glass layer of larger or smaller sizes. In an exemplary embodiment, the glass composition of the glass 12 and / or 20 includes: SiO2, B2O3, and Na2O, wherein (SiO2+B2O3)≥66 mol%, and Na2O≥9 mol%. In some embodiments, the glass composition suitable for the glass layer 12 and / or 20 also includes at least one of K2O, MgO, and CaO. In a particular embodiment, the glass composition for glass layers 12 and / or 20 may include: 61-75 mol% SiO2; 7-15 mol% Al2O3; 0-12 mol% B2O3; 9-21 mol% Na2O; 0-4 mol% K2O; 0-7 mol% MgO; and 0-3 mol% CaO.

[0081] Another example of a glass composition suitable for glass layers 12 and / or 20 includes: 60-70 mol% SiO2; 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; less than 50 ppm As2O3; and less than 50 ppm Sb2O3; wherein 12 mol% ≤ (Li2O+Na2O+K2O) ≤ 20 mol% and 0 mol% ≤ (MgO+CaO) ≤ 10 mol%.

[0082] Even further, another example of a glass composition suitable for glass layers 12 and / or 20 includes: 63.5-66.5 mol % SiO2; 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; less than 50 ppm As2O3; and less than 50 ppm Sb2O3; wherein 14 mol % ≤ (Li2O + Na2O + K2O) ≤ 18 mol %, and 2 mol % ≤ (MgO + CaO) ≤ 7 mol %.

[0083] In a specific embodiment, an alkali aluminosilicate glass composition suitable for glass layer 12 and / or 20 comprises: aluminum oxide; at least one alkali metal; and in some embodiments greater than 50 mol% SiO2, in other embodiments at least 58 mol% SiO2, and in other embodiments at least 60 mol% SiO2; wherein the ratio ((Al2O3+B2O3) / ∑ modifier)>1, wherein the ratios of the components are in mol% and the modifier is an alkali metal oxide. In a specific embodiment, such a glass composition comprises: 58-72 mol% SiO2, 9-17 mol% Al2O3, 2-12 mol% B2O3, 8-16 mol% Na2O, and 0-4 mol% K2O, wherein the ratio ((Al2O3+B2O3) / ∑ modifier)>1.

[0084] In another embodiment, the glass layers 12 and / or 20 may include an alkali aluminosilicate glass composition comprising: 64-68 mol% SiO2; 12-16 mol% Na2O; 8-12 mol% Al2O3; 0-3 mol% B2O3; 2-5 mol% K2O; 4-6 mol% MgO; and 0-5 mol% CaO, wherein 66 mol%≤SiO2+B2O3+CaO≤69 mol%; Na2O+K2O+B2O3+MgO+CaO+SrO>10 mol%; 5 mol%≤MgO+CaO+SrO≤8 mol%; (Na2O+B2O3)-Al2O3≤2 mol%; 2 mol%≤Na2O-Al2O3≤6 mol%; and 4 mol%≤(Na2O+K2O)-Al2O3≤10 mol%.

[0085] In alternative embodiments, the glass layers 12 and / or 20 may include an alkali aluminosilicate glass composition comprising: 2 mol% or more of Al2O3 and / or ZrO2 or 4 mol% or more of Al2O3 and / or ZrO2. In one or more embodiments, the glass layers 12 and / or 20 include a glass composition comprising: SiO2 in an amount of about 67 mol% to about 80 mol%, Al2O3 in an amount of about 5 mol% to about 11 mol%, and an alkali metal oxide (RO) in an amount greater than about 5 mol% (e.g., about 5 mol% to about 27 mol%). In one or more embodiments, the amount of R2O includes: Li2O in an amount of about 0.25 mol% to about 4 mol%, and K2O in an amount equal to or less than 3 mol%. In one or more embodiments, the glass composition includes a non-zero amount of MgO and a non-zero amount of ZnO.

[0086] In other embodiments, the glass layers 12 and / or 20 are formed from a glass composition exhibiting: an amount of SiO2 of about 67 mol% to about 80 mol%, an amount of Al2O3 of about 5 mol% to about 11 mol%, an amount of alkali metal oxide (R2O) greater than about 5 mol% (e.g., about 5 mol% to about 27 mol%), wherein the glass composition is substantially free of Li2O, and a non-zero amount of MgO; and a non-zero amount of ZnO.

[0087] In other embodiments, the glass layers 12 and / or 20 are aluminosilicate glass articles comprising a glass composition including: SiO2 in an amount of about 67 mol% or greater; and a sag temperature of about 600° C. to about 710° C. In other embodiments, the glass layers 12 and / or 20 are formed from aluminosilicate glass articles comprising a glass composition including: SiO2 in an amount of about 68 mol% or greater; and a sag temperature of about 600° C. to about 710° C. (as defined herein).

[0088] In some embodiments, the glass layers 12 and / or 20 are formed of mutually different glass materials that differ in any one or more of composition, thickness, level of strengthening, and forming method (e.g., float formation rather than fusion formation). In one or more embodiments, the glass layers 12 and / or 20 described herein have a sag temperature of about 710° C. or less or about 700° C. or less. In one or more embodiments, one of the glass layers 12 and 20 is a soda-lime glass sheet, and the other of the glass layers 12 and 20 is any of the non-soda-lime glass materials discussed herein. In one or more embodiments, the glass layers 12 and / or 20 include a glass composition comprising: SiO2 in an amount of about 68 mol% to about 80 mol%, Al2O3 in an amount of about 7 mol% to about 15 mol%, B2O3 in an amount of about 0.9 mol% to about 15 mol%, a non-zero amount of P2O5 up to and including about 7.5 mol%, Li2O in an amount of about 0.5 mol% to about 12 mol%, and Na2O in an amount of about 6 mol% to about 15 mol%.

[0089] In some embodiments, the glass composition of glass layer 12 and / or 20 can include oxides that impart color or tint to the glass article. In some embodiments, the glass composition of glass layer 12 and / or 20 includes oxides that prevent discoloration of the glass article when the glass article is exposed to ultraviolet radiation. Examples of such oxides include, but are not limited to, oxides of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Ce, W, and Mo.

[0090] The glass layer 12 and / or 20 can have a refractive index of about 1.45 to about 1.55. As used herein, the refractive index value is relative to a wavelength of 550nm. The glass layer 12 and / or 20 can be characterized by the way it is formed. For example, the glass layer 12 and / or 20 can be characterized as being float formable (i.e., formed by a float process), being draw-down formable, specifically, being fused-formable or being slit-drawn (i.e., being formed by a draw-down process such as a fusion-draw process or a slit-draw process). In one or more embodiments, the glass layer 12 and / or 20 described herein can exhibit an amorphous microstructure, and can be substantially free of crystals or crystallites. In other words, in such embodiments, the glass article excludes glass-ceramic materials.

[0091] In one or more embodiments, when the thickness of the glass layer 12 and / or 20 is 0.7 mm, the glass layer 12 and / or 20 exhibits an average total solar transmittance of about 88% or less over a wavelength range of about 300 nm to about 2500 nm. For example, the glass layer 12 and / or 20 exhibits an average total solar transmittance of about 60% to about 88%, about 62% to about 88%, about 64% to about 88%, about 65% to about 88%, about 66% to about 88%, about 68% to about 88%, about 70% to about 88%, about 72% to about 88%, about 60% to about 86%, about 60% to about 85%, about 60% to about 84%, about 60% to about 82%, about 60% to about 80%, about 60% to about 78%, about 60% to about 76%, about 60% to about 75%, about 60% to about 74%, or about 60% to about 72%.

[0092] In one or more embodiments, the glass layer 12 and / or 20 exhibits an average transmittance of about 75% to about 85% for a thickness of 0.7 mm or 1 mm over a wavelength range of about 380 nm to about 780 nm. In some embodiments, the average transmittance over this thickness and this wavelength range may be in the range of about 75% to about 84%, about 75% to about 83%, about 75% to about 82%, about 75% to about 81%, about 75% to about 80%, about 76% to about 85%, about 77% to about 85%, about 78% to about 85%, about 79% to about 85%, or about 80% to about 85%. In one or more embodiments, the glass layer 12 and / or 20 exhibits a T of 50% or less for a thickness of 0.7 mm or 1 mm over a wavelength range of about 300 nm to about 400 nm. uv-380 or T uv-400 (e.g., 49% or less, 48% or less, 45% or less, 40% or less, 30% or less, 25% or less, 23% or less, 20% or less, or 15% or less).

[0093] In one or more embodiments, the glass layers 12 and / or 20 may be strengthened to include compressive stress extending from the surface to a depth of compression (DOC). The compressive stress region is balanced by a central portion exhibiting tensile stress. At the DOC, the stress transitions from positive (compressive) stress to negative (tensile) stress.

[0094] In one or more embodiments, the glass layers 12 and / or 20 can be mechanically strengthened by exploiting the mismatch in thermal expansion coefficients between portions of the article to create regions of compressive stress and a central region exhibiting tensile stress. In some embodiments, the glass article can be thermally strengthened by heating the glass to a temperature below the glass transition point and then rapidly quenching.

[0095] In one or more embodiments, the glass layers 12 and / or 20 can be chemically strengthened by ion exchange. During the ion exchange process, ions at or near the surface of the glass layers 12 and / or 20 are replaced or exchanged with larger ions of the same valence or oxidation state. In those embodiments where the glass layers 12 and / or 20 comprise an alkali aluminosilicate glass, the ions in the surface layers of the article and the larger ions are monovalent alkali metal cations, such as Li + 、Na + , K + , Rb + and Cs + Alternatively, the monovalent cations in the surface layer may be monovalent cations other than alkali metal cations, such as Ag. + In such embodiments, the monovalent ions (or cations) exchanged into the glass layers 12 and / or 20 generate stress.

[0096] Aspect (1) of the present disclosure pertains to a method for evaluating the cold formability of a complex curved glass laminate product comprising a first glass sheet and a second glass sheet, the method comprising: obtaining a first geometric parameter (G1) and a second geometric parameter (G2) of a complex curved first glass sheet of the glass laminate product; calculating a cold forming estimate (CFE) value, the cold forming estimate (CFE) value being related to the stress experienced by the first glass sheet during cold forming, wherein the CFE value comprises B1*G1+B2*G2, wherein B1 and B2 are coefficients calculated to relate G1 and G2 to the CFE value; and comparing the calculated CFE value with a cold forming threshold value, the cold forming threshold value being related to the likelihood of defects being formed in the complex curved glass laminate product during cold forming.

[0097] Aspect (2) belongs to the method of aspect (1), which also includes determining that the curved glass laminate article is suitable for cold forming when the calculated CFE value is less than the cold forming threshold.

[0098] Aspect (3) belongs to the method of aspect (1) or aspect (2), wherein the average thickness of the first glass sheet is greater than the average thickness of the second glass sheet, and the first glass sheet is formed of a first glass composition that is different from a second glass composition of the second glass sheet.

[0099] Aspect (4) belongs to the method of aspect (3), wherein B1, B2 and the cold forming threshold are functions of the first glass composition.

[0100] Aspect (5) belongs to the method of aspect (3), wherein the first glass composition is soda lime glass.

[0101] Aspect (6) belongs to the method of aspect (5), wherein the first glass sheet is an unstrengthened glass sheet and the cold forming threshold is 20 MPa, and also includes determining that the curved glass laminate product is suitable for cold forming when the calculated CFE value is less than 20 MPa.

[0102] Aspect (7) belongs to the method of aspect (5), wherein the first glass sheet is a heat-strengthened glass sheet and the cold forming threshold is 50 MPa, and also includes determining that the curved glass laminate article is suitable for cold forming when the calculated CFE value is less than 50 MPa.

[0103] Aspect (8) belongs to the method of any one of aspects (2) to (7), wherein the second glass composition is an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition.

[0104] Aspect (9) belongs to the method of any one of aspects (2) to (8), further comprising determining B1 and B2 by multiple linear regression analysis of stress determined by finite element analysis of multiple complex curved glass laminate articles.

[0105] Aspect (10) belongs to the method of any one of aspects (1) to (9), wherein the cold forming threshold is the maximum allowable stress of the first glass sheet, which is determined by comparing the stacked test samples with the stress level predicted using finite element analysis.

[0106] Aspect (11) belongs to the method of any one of aspects (1) to (10), wherein the first glass sheet comprises: a length L, a width W and a chord height, wherein G1 = L / W, G2 = chord height, B1 = 1 and B2 = 0.5.

[0107] Aspect (12) belongs to the method of any one of aspects (1) to (10), wherein the first glass sheet further includes: an inner surface, an outer surface opposite to the inner surface, a width W, a length L, and an average thickness T1, wherein the complex curved shape has a chord height CH, a bending depth (DOB), a minimum first radius of curvature R1, a second minimum radius of curvature R2, and a maximum Gaussian curvature GC, wherein the second glass layer further includes: an inner surface, an outer surface, and an average thickness T2, wherein (0.05673*W-0.1035*L-0.0031*CH+6.99003*CH+0.1855*R1+0.00115*R2+4.633988*GC-0.1836*T1-101.95*T2) is less than the cold forming threshold.

[0108] Aspect (13) pertains to a method for cold - forming a complexly - curved glass laminate product, which includes: supporting a first glass sheet having a complexly - curved shape, a first major surface, and a second major surface; supporting a second glass sheet on the first glass sheet, wherein the second glass sheet has a first major surface, a second major surface, and a shape different from the complexly - curved shape; placing a polymer interlayer material between the second major surface of the first glass sheet and the first major surface of the second glass sheet; bending the second glass sheet material to conform to the complexly - curved shape of the first glass sheet material, wherein during the bending process, the maximum temperature of the first glass sheet is less than the glass transition temperature of the glass material of the first glass sheet, and the maximum temperature of the second glass sheet is less than the glass transition temperature of the glass material of the second glass sheet; wherein the complexly - curved shape has a first geometric parameter (G1) and a second geometric parameter (G2), and the first principal stress experienced by the first glass sheet during the bending process is less than or equal to an estimated stress value (B1*G1 + B2*G2), where B1 and B2 are coefficients determined to relate G1 and G2 to the stress experienced by the first glass sheet during the bending process.

[0109] Aspect (14) pertains to the method of aspect (13), wherein the average thickness of the first glass sheet is greater than the average thickness of the second glass sheet, and the glass material of the first glass sheet is different from the glass material of the second glass sheet.

[0110] Aspect (15) pertains to the method of aspect (13) or aspect (14), wherein the first glass sheet is an un - strengthened glass sheet, and the estimated stress value is less than 20 MPa.

[0111] Aspect (16) pertains to the method of aspect (13) or aspect (14), wherein the first glass sheet is a thermally - strengthened glass sheet, and the estimated stress value is 50 MPa.

[0112] Aspect (17) is the method of any one of aspects (13) to (16), wherein the glass material of the second glass sheet is an alkaline aluminosilicate glass composition or an alkaline aluminoborosilicate glass composition, and the glass material of the first glass sheet is a soda - lime glass composition.

[0113] Aspect (18) pertains to a cold - formed glass laminate product, which includes: a first glass layer, the first glass layer comprising: an inner surface, an outer surface opposite the inner surface, a width W, a length L, a complexly - curved shape having a chord height CH, wherein - 0.14 < L / W - 0.05*(CH) < 0.223; and a second glass layer, the second glass layer comprising: an inner surface, an outer surface; and a polymer interlayer disposed between the inner surface of the first glass layer and the inner surface of the second glass layer.

[0114] Aspect (19) is the cold-formed glass laminate product of aspect (18), wherein the average thickness T1 of the first glass layer is greater than the average thickness T2 of the second glass layer.

[0115] Aspect (20) is the cold-formed glass laminate article of aspect (19), wherein T1 is 1 mm to 4 mm, and T2 is .3 mm to 1 mm.

[0116] Aspect (21) is the cold-formed glass laminate article of any one of aspects (18) to (20), wherein W is 300 mm to 1800 mm, L is 230 mm to 1600 mm, and CH is 1 mm to 45 mm.

[0117] Aspect (22) is the cold-formed glass laminate article of any one of aspects (18) to (21), wherein the glass material of the first glass layer is different from the glass material of the second glass layer.

[0118] Aspect (23) is a cold-formed glass laminate product according to aspect (22), wherein the glass material of the second glass layer is an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition, and the glass material of the first glass sheet is a soda-lime glass composition.

[0119] Aspect (24) is the cold-formed glass laminate article of any one of aspects (18) to (23), wherein the second glass layer is a chemically strengthened glass material.

[0120] Aspect (25) belongs to a cold-formed glass laminate product, which includes: a first glass layer, the first glass layer includes: an inner surface, an outer surface opposite to the inner surface, a width W, a length L, an average thickness T1, and a complex curved shape with a chord height CH, a bending depth (DOB), a minimum first radius of curvature R1, a second minimum radius of curvature R2 and a maximum Gaussian curvature GC; a second glass layer, the second glass layer includes: an inner surface, an outer surface and an average thickness T2; and an intermediate layer arranged between the inner surface of the first glass layer and the inner surface of the second glass layer, wherein (0.05673*W-0.1035*L-0.0031*CH+6.99003*CH+0.1855*R1+0.00115*R2+4.633988*GC-0.1836*T1-101.95*T2) is less than 80MPa.

[0121] Aspect (26) is the cold-formed glass laminate article of aspect (25), wherein T1 is greater than T2.

[0122] Aspect (27) is the cold-formed glass laminate article of aspect (25) or aspect (26), wherein T1 is 1 mm to 4 mm, and T2 is .3 mm to 1 mm.

[0123] Aspect (28) is a cold-formed glass laminate product according to any one of aspects (25) to (27), wherein W is 300 mm to 1800 mm, L is 230 mm to 1600 mm, CH is 1 mm to 45 mm, DOB is 5 mm to 210 mm, R1 is 40 mm to 5000 mm, R2 is 740 mm to 32500 mm, and GC is 0.14e-7 1 / mm 2 Up to 15e-7 1 / mm 2 .

[0124] Aspect (29) is the cold-formed glass laminate article of any one of aspects (25) to (28), wherein the glass material of the first glass layer is different from the glass material of the second glass layer.

[0125] Aspect (30) is a cold-formed glass laminate product according to aspect (29), wherein the glass material of the second glass layer is an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition, and the glass material of the first glass sheet is a soda-lime glass composition.

[0126] Aspect (31) is the cold-formed glass laminate article of any one of aspects (25) to (30), wherein the second glass layer is a chemically strengthened glass material.

[0127] Unless otherwise stated, it is not intended that any method described herein be construed as requiring that its steps be performed in a specific order. Therefore, when a method claim does not actually state that its steps follow a certain order or it does not specifically indicate in any other way in the claims or specification that the steps are limited to a specific order, it is not intended to imply any particular order. In addition, as used herein, the article "a" is intended to include one or more than one component or element, and is not intended to be construed as meaning only one.

[0128] It will be apparent to those skilled in the art that various modifications and variations may be made without departing from the spirit or scope of the illustrated embodiments. Because those skilled in the art may conceive of various modifications, combinations, sub-combinations, and variations of the disclosed embodiments that incorporate the spirit and substance of the embodiments, the disclosed embodiments should be considered to include all of the contents within the scope of the appended claims and their equivalents.

Claims

1. A cold-formed laminate for an automobile, comprising: A first glass layer, which is thermoformed and includes a length L, a width W, and a complex curved shape having a chord height CH, wherein -0.14 <L / W-0.05mm -1 *(CH)<0.223; a second glass layer that is cold formed against the first glass layer at a temperature below a softening temperature of the second glass layer to have the complex curved shape; and a polymer interlayer disposed between the first glass layer and the second glass layer, the polymer interlayer holding the first glass layer against the second glass layer in the complex curved shape, wherein: The first glass layer has an average thickness T1, and the second glass layer has an average thickness T2, and T1 is at least 2.5 times that of T1.

2. The cold-formed laminate according to claim 1, wherein: T1 is greater than or equal to 1.5 mm and less than or equal to 4.0 mm.

3. The cold-formed laminate according to claim 2, wherein: T2 is greater than or equal to 0.3 mm and less than or equal to 1.0 mm.

4. The laminate according to claim 1, wherein The second glass layer is flat prior to being cold formed against the first glass layer.

5. The cold-formed laminate according to any one of claims 1 to 4, wherein: The first glass layer is formed from a first glass composition, and the second glass layer is formed from a second glass composition different from the first glass composition.

6. The cold-formed laminate of claim 5, wherein: the first composition is a soda-lime-silicate glass, and the second composition is an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition, The second composition is chemically enhanced, and The second glass layer includes a compression depth range of greater than or equal to 30 μm and less than or equal to 90 μm and a maximum surface compression stress of greater than or equal to 300 MPa and less than or equal to 1000 MPa.

7. The cold-formed laminate according to any one of claims 1 to 4, wherein: The first glass layer includes a bend depth DOB greater than or equal to 5 mm and less than or equal to 210 mm.

8. The cold-formed laminate according to claim 7, wherein: L / W is greater than 0.0 and less than or equal to 0.

7.

9. The cold-formed laminate according to claim 8, wherein: CH is greater than or equal to 1 mm and less than or equal to 45 mm.

10. The cold-formed laminate according to any one of claims 1 to 4, wherein: The laminate is a sidelight.

11. A cold-formed laminate for use in a vehicle, comprising: a first glass layer comprising: a length L, a width W, an average thickness T1, a complex curved shape having a non-zero chord height CH, a non-zero depth of bend (DOB), a non-zero minimum first radius of curvature R1, a non-zero minimum second radius of curvature R2, and a non-zero maximum Gaussian curvature GC; comprising a second glass layer having an average thickness T2; and an intermediate layer disposed between an inner surface of the first glass layer and an inner surface of the second glass layer; in, (0.05673 MPa / mm * W - 0.1035 MPa / mm * L - 0.0031 MPa / mm * DOB + 6.99003 MPa / mm * CH + 0.01855 MPa / mm * R1 + 0.00115 MPa / mm * R2 + 4.633988 MPa * mm 2 * 10 7 * GC - 0.1836 MPa / mm * T1 - 101.95 MPa / mm * T2) is less than 80 MPa, W is greater than or equal to 300 mm and less than or equal to 1800 mm, L is greater than or equal to 230 mm and less than or equal to 1600 mm, T1 is at least 2.5 times of T2. DOB is greater than or equal to 5.0 mm and less than or equal to 210 mm, CH is greater than or equal to 1 mm and less than or equal to 45 mm, and The first glass layer is hot formed to have a complex shape, and the second glass layer is cold formed against the first glass layer at a temperature below a softening temperature of the second glass layer to have the complex curved shape.

12. The cold-formed laminate according to claim 11, wherein: T1 is greater than or equal to 1.5 mm and less than or equal to 4.0 mm.

13. The cold-formed laminate according to claim 12, wherein: T2 is greater than or equal to 0.3 mm and less than or equal to 1.0 mm.

14. The cold-formed laminate of claim 11, wherein: forming the first glass layer from a first glass composition, and forming the second glass layer from a second glass composition different from the first glass composition, the first composition is a soda-lime-silicate glass, and the second composition is an alkali aluminosilicate glass composition or an alkali aluminoborosilicate glass composition, The second composition is chemically enhanced, and The second glass layer includes a compression depth range of greater than or equal to 30 μm and less than or equal to 90 μm and a maximum surface compression stress of greater than or equal to 300 MPa and less than or equal to 1000 MPa.

15. A cold formed laminate as claimed in any one of claims 11 to 14, wherein: When CH is greater than or equal to 8 mm, GC is less than 13x10 -7 mm -2 .

16. A cold formed laminate as claimed in any one of claims 11 to 14, wherein: 0.05673 MPa / mm * W - 0.1035 MPa / mm * L - 0.0031 MPa / mm * DOB + 6.99003 MPa / mm * CH + 0.01855 MPa / mm * R1 + 0.00115 MPa / mm * R2 + 4.633988 MPa * mm 2 * 10 7 * GC - 0.1836 MPa / mm * T1 - 101.95 MPa / mm * T2) is less than 50 MPa.

17. A cold formed laminate as claimed in any one of claims 11 to 14, wherein: 0.05673 MPa / mm * W - 0.1035 MPa / mm * L - 0.0031 MPa / mm * DOB + 6.99003 MPa / mm * CH + 0.01855 MPa / mm * R1 + 0.00115 MPa / mm * R2 + 4.633988 MPa * mm 2 * 10 7 * GC - 0.1836 MPa / mm * T1 - 101.95 MPa / mm * T2) is less than 20 MPa.

18. A cold formed laminate as claimed in any one of claims 11 to 14, wherein: L / W is greater than or equal to 0.0 and less than or equal to 0.

7.

19. A cold formed laminate as claimed in any one of claims 11 to 14, wherein: The laminate is a sidelight.

Images