Glass articles having high aspect ratio adhesive beads and methods of making the same

Abstract

A glass article comprising: a frame having a frame support surface; a glass sheet having a first major surface and a second major surface, wherein the second major surface is opposite the first major surface; and an adhesive bead disposed between the frame support surface and the second major surface. The adhesive bead defines a bead path. The adhesive bead has a cross-section perpendicular to the bead path, and the cross-section comprises a width and a height. The height is the maximum dimension perpendicular to the second major surface of the glass sheet, and the width is the maximum dimension parallel to the second major surface of the glass sheet. An aspect ratio of the height to the width is at least 0.6, and the width is 2 mm or less.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 037,864, filed June 11, 2020, the contents of which are incorporated herein by reference in their entirety. Background Technology

[0003] This disclosure relates to glass articles for use in vehicle interior systems, and more particularly to glass articles with adhesive beads having a high aspect ratio of at least 0.6 height to width, and methods for producing the same.

[0004] Vehicle interior trim can be incorporated into glass surfaces as part of the vehicle's aesthetic and functional design. These glass surfaces can be bonded to a frame system that attaches them to the vehicle interior trim. Typically, the frame and glass surfaces are made of different materials with different thermal expansion properties. Therefore, thermal stresses can be generated during thermal cycling between extreme hot and cold temperatures. These thermal stresses can be so great that they can cause failure in the bonding process that holds the glass surfaces to the frame system, especially when the glass surfaces are cold-formed and bonded to the frame system. Summary of the Invention

[0005] According to one aspect, embodiments of this disclosure relate to a glass article comprising: a frame having a frame support surface; a glass sheet having a first main surface and a second main surface, wherein the second main surface is opposite to the first main surface; and adhesive beads disposed between the frame support surface and the second main surface. The adhesive beads define a bead path. The adhesive beads have a cross-section perpendicular to the bead path, and the cross-section includes a width and a height. The height is a maximum dimension perpendicular to the second main surface of the glass sheet, and the width is a maximum dimension parallel to the second main surface of the glass sheet. The aspect ratio of the height to the width is at least 0.6, and the width is 2 mm or less.

[0006] According to another aspect, embodiments of this disclosure relate to a method of forming glass. The glass article includes a glass sheet having a first main surface and a second main surface, wherein the second main surface is opposite to the first main surface. The glass article also includes a frame adhered to the glass sheet. In the method, adhesive beads are applied in a bead path to the second main surface of the glass sheet or to a frame support surface of the frame. The adhesive beads have a first height and a first width, the first height being perpendicular to the second main surface on which the adhesive beads are applied or the frame support surface, wherein the first width and the first height are perpendicular to the bead path. The adhesive beads are compressed between the second main surface of the glass sheet and the frame support surface to a second height and a second width. The adhesive beads expand to a third height and a third width. The third height is greater than the second height, and the aspect ratio of the third height to the third width is at least 0.6.

[0007] According to another aspect, embodiments of this disclosure relate to a system for shaping a glass article. The glass article includes a glass sheet adhered to a frame by adhesive beads. The system includes a chuck having a bending surface over which the glass sheet is bent. The system also includes a press configured to position the frame above the glass sheet. Further, the system includes a nozzle configured to dispense the adhesive beads onto the glass sheet. The press is configured to position the frame at a first height above the glass sheet to compress the adhesive beads, and the press is configured to further position the frame at a second height above the glass sheet, the second height being greater than the first height.

[0008] Further features and advantages will be set forth in the following detailed description, which will be apparent to those skilled in the art from the description, or will be recognized by practice of the embodiments described herein, including the following detailed description, the claims, and the accompanying drawings.

[0009] It should be understood that the foregoing general description and the following detailed description are merely exemplary and intended to provide an overview or framework for understanding the nature and features of the claims. The accompanying drawings, which are incorporated in and form part of this specification, are included to provide further understanding. Attached Figure Description

[0010] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various aspects of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings:

[0011] Figure 1 This is a perspective view of a vehicle interior with a curved glass surface according to an exemplary embodiment;

[0012] Figure 2A and Figure 2B A method for use according to an exemplary embodiment is described. Figure 1 A side view of an embodiment of curved glasswork in a vehicle interior;

[0013] Figure 3 An embodiment of a cold forming arrangement for producing glass articles according to an exemplary embodiment is described;

[0014] Figures 4A to 4D The steps of a process according to an exemplary embodiment for compressing adhesive beads during cold forming and positioning a frame over a glass sheet are schematically depicted; and

[0015] Figure 5A and Figure 5B Uncompressed and compressed adhesive beads according to exemplary embodiments are depicted respectively. Detailed Implementation

[0016] Various embodiments illustrated in the accompanying drawings will now be discussed in detail with reference to examples thereof. Glass articles for vehicle interior systems are disclosed herein, wherein a frame is bonded to a glass sheet using adhesive beads having a high aspect ratio. Specifically, the height of the adhesive beads perpendicular to the glass surface is at least 0.6 times the width of the adhesive beads parallel to the glass surface. Advantageously, such high aspect ratio adhesive beads are better able to handle stresses caused by thermal cycling, while still providing a minimized footprint that maximizes the display area.

[0017] Embodiments of a method for manufacturing glass articles with adhesive beads having a high aspect ratio are also disclosed. In this method, a frame compresses the adhesive beads at a desired final height, and then retracts the frame to pull the adhesive beads back to the desired height. In this way, a high aspect ratio is provided, and the surface contact between the adhesive and the glass, as well as between the adhesive and the frame, is increased. Various embodiments of glass articles with adhesive beads having a high aspect ratio and methods for manufacturing the same are disclosed in conjunction with the exemplary embodiments provided below and depicted in the accompanying drawings. These embodiments are provided by way of illustration rather than limitation.

[0018] Figure 1Exemplary interiors 10 of vehicles including three different embodiments 20, 30, and 40 of vehicle interior systems are shown. Vehicle interior system 20 includes a base having a curved surface 24 including a display 26, shown as a center console base 22. Vehicle interior system 30 includes a base having a curved surface 34 including a display 36, shown as an instrument panel base 32. Instrument panel base 32 typically includes an instrument panel 38 that may also include a display. Vehicle interior system 40 includes a base having a display 46 and a curved surface 40, shown as a steering wheel base 42. In one or more embodiments, the vehicle interior system includes a base that is an armrest, pillar, seat back, floor, headrest, door panel, or any part of the vehicle interior that includes a curved surface. In other embodiments, the base is part of a housing for a freestanding display (i.e., a display not permanently attached to a part of the vehicle).

[0019] The embodiments of the curved glass articles described herein are particularly applicable to each vehicle interior system 20, 30, 40. In some such embodiments, the glass articles discussed herein may include cover glass sheets that also cover non-display surfaces such as dashboards, center consoles, steering wheels, door panels, etc. In such embodiments, the glass material may be selected based on its weight, aesthetic appearance, etc., and may be equipped with a coating (e.g., an ink or pigment coating) with a pattern (e.g., a brushed metallic finish, a wood grain finish, a leather finish, a colored finish, etc.) to visually match the glass components with adjacent non-glass components. In specific embodiments, such ink and pigment coatings may have a level of transparency that provides a non-load-bearing safety surface or color-matching functionality when the displays 26, 36, 38, 46 are inactive. Furthermore, although Figure 1 The vehicle interiors depict vehicles in the form of automobiles (e.g., cars, vans, buses, etc.), but the glassware disclosed herein can also be incorporated into other vehicles such as trains, marine vessels (boats, ships, submarines, etc.), and aircraft (e.g., drones, airplanes, jets, helicopters, etc.).

[0020] In the implementation, the curved surfaces 24, 34, and 44 can be any of various curved shapes, such as... Figure 2A and Figure 2B The V-shape or C-shape is shown in the image respectively. First refer to... Figure 2AThe image shows a side view of an embodiment of a V-shaped glass article 50. The glass article 50 includes a glass sheet 52 having a first main surface 54, a second main surface 56 opposite to the first main surface 54, and a subsurface 58 bonding the first main surface 54 to the second main surface 56. The first main surface 54 and the second main surface 56 define a thickness T of the glass sheet 52. In this embodiment, the thickness T of the glass sheet 52 is 0.3 mm to 2 mm, particularly 0.5 mm to 1.1 mm. In a vehicle, the first main surface 54 faces the vehicle occupant.

[0021] In an embodiment, the first main surface 54 and / or the second main surface 56 include one or more surface treatments. Examples of surface treatments that may be applied to one or both of the first main surface 54 and the second main surface 56 include anti-glare coatings, anti-reflective coatings, coatings that provide tactile functionality, decorative (e.g., ink or pigment) coatings, and easy-to-clean coatings.

[0022] exist Figure 2A As can be seen, the glass sheet 52 has a curved region 60 disposed between the first flat section 62a and the second flat section 62b. In an embodiment, the radius of curvature R of the curved region 60 ranges from 75 mm to a radius of curvature smaller than that of a substantially flat or planar surface (e.g., R = 10 m). In particular, the curved region 60 has a radius of curvature R ranging from 150 mm to 3000 mm. Further, as... Figure 2A As shown, the curved region 60 defines a concave surface relative to the first main surface 54, but in other embodiments, the curved region 60 defines a convex surface relative to the first main surface 54 instead.

[0023] exist Figure 2A In the glass article 50, a frame 64 is adhered to the second primary surface 56 of a glass sheet 52 using adhesive beads 66. In an embodiment, the adhesive beads 66 are structural adhesives, such as polyurethane adhesives. Other materials are also feasible. In an embodiment, the material of the adhesive beads 66 has an elastic modulus of 0.1 MPa to 300 MPa. Further, in an embodiment, the material of the adhesive beads 66 has a viscosity of 1 kcps to 500 kcps.

[0024] Partly, frame 64 facilitates the mounting of glass items 50 to the vehicle interior base (such as...). Figure 1The center console base 22, instrument panel base 32, and / or steering wheel base 42 are shown in the diagram. Furthermore, the frame 64 has a curved frame support surface 65 that holds the glass sheet 52 in its curved shape (at least in the curved region 60). In this embodiment, the glass sheet 52 is shaped in a non-permanent manner in the curved region 60. That is, if the glass sheet 52 is not adhered to the frame 64 using adhesive beads 66, the glass sheet 52 will spring back to its flat, non-curved configuration. Therefore, the glass sheet 52 is stressed to create the curved surface and remains stressed throughout the life of the glass article 50.

[0025] The stress in the glass sheet 52 tends to cause it to pull away from the frame 64, meaning the adhesive beads 66 are also under stress. This stress can be further exacerbated by stress caused by thermal cycling. In particular, the glass sheet 52 has a different coefficient of thermal expansion than the frame 64, which is typically a metal, composite, or plastic component. This difference in coefficient of thermal expansion means that the glass sheet 52 and the frame expand or contract differently during thermal cycling between extreme temperatures (e.g., as low as -40°C and as high as 80°C), resulting in additional stress in the adhesive beads 66. To avoid failure caused by thermal stress that increases to the normal mechanical stress associated with bending, the adhesive beads 66 have a high aspect ratio of at least 0.6 height relative to width. In conventional glass articles, the aspect ratio of adhesive beads is 0.5 or less. Providing thicker adhesive beads 66 (i.e., adhesive beads with a relatively high aspect ratio) reduces the stress generated in the adhesive beads 66 during thermal cycling because the shear stress associated with uneven thermal expansion is distributed over the thicker adhesive beads 66. Advantageously, the reduced stress experienced by the adhesive beads 66 allows for the use of a wider range of materials in manufacturing and larger part designs.

[0026] While mechanical and thermal stresses can be addressed by providing larger adhesive beads, aesthetic considerations limit how wide the adhesive beads can be. In particular, minimizing the contact area between the adhesive beads 66 and the glass sheet 52 in order to maximize the display area of ​​the glass article 50 is desirable.

[0027] Figure 2B Another embodiment of the glass article 50, particularly the C-shaped glass article 50, is depicted. Figure 2A Compared to V-shaped glass products of 50, Figure 2BThe C-shaped glass article 50 has a larger curved region 60 and shorter flat sections 62a, 62b. However, V-shape and C-shape are two examples of curved glass articles 50 that can be formed according to this disclosure. In other embodiments, the glass article 50 may in particular include a curved region 60 having relative curvatures to form an S-shape, a curved region 60 accompanying a flat section 62a to form a J-shape, and a curved region 60 separated from the flat section 62a to form a U-shape.

[0028] The glass article 50 according to this disclosure is formed by cold forming technology. Generally speaking, the cold forming process involves, for example, Figure 3 The diagram illustrates applying a bending force to the glass sheet 52 while it is positioned on the chuck 68. Thus, the chuck 68 has a bending-shaped surface 70, and the glass sheet 52 is bent to conform to this surface. Advantageously, surface treatments are more easily applied to a flat glass sheet 52 before a curved surface is established within it, and cold forming allows the glass sheet 52 to be bent without damaging the surface treatment (compared to the tendency for high-temperature surface treatments associated with thermoforming, which requires applying the surface treatment to the curved article in a more complex process). In embodiments, the cold forming process is performed at a temperature below the glass transition temperature of the glass sheet 52. In particular, the cold forming process can be performed at room temperature (e.g., about 20°C) or slightly elevated temperatures, such as 200°C or lower, 150°C or lower, 100°C or lower, or 50°C.

[0029] In one embodiment, the bending force applied to the glass sheet 52 can be in the form of vacuum pressure drawn through the chuck 68. In another embodiment, the chuck 68 includes an internal channel with a port on its forming surface 70. When the glass sheet 52 is positioned on the forming surface 70, a vacuum is drawn through this channel to hold the glass product 52 against the chuck and conform to the curvature of the forming surface 70. In other embodiments, the forming surface 70 can utilize other techniques to hold the glass sheet 52 conforming to the curvature. For example, the forming surface 70 can be a self-adhesive material configured to provide sufficient adhesion to hold the glass sheet 52 in a bent configuration during cold forming, or the chuck 68 can operate in conjunction with a press or fixture that holds the glass sheet 52 conforming to the forming surface 70 during cold forming.

[0030] exist Figure 3In the embodiment shown, adhesive beads 66 are applied to the second primary surface 56 of the glass sheet 52, and the frame 64 is lowered onto the glass sheet 52. However, in other embodiments, the adhesive beads 66 may instead be applied to the frame support surface 65 of the frame 64. In either case, the frame 64 will compress the adhesive beads 66 to a desired aspect ratio between the frame support surface 65 and the second primary surface 56 of the glass sheet 52. Figure 3 As can be seen, the adhesive beads 66 are being applied to the glass sheet 52 in such a way that the shape outlined by the adhesive beads 66, i.e., the "bead path," substantially matches the shape of the frame 64. In one embodiment, the adhesive beads 66 define a closed bead path such that the adhesive beads 66 are continuous on the glass sheet 52. In other embodiments, the adhesive beads 66 may have discontinuous bead paths, for example, with breaks between the cross-sections of the adhesive beads 66.

[0031] In the implementation method, via such Figure 3 The nozzle 71 shown, with a circular port 73, applies adhesive beads 66. Advantageously, such nozzles can be easily manufactured because, compared to a specific nozzle with, for example, a triangular port, the nozzle's orientation relative to the glass sheet 52 is not restricted, which is largely aligned with the specific orientation of the glass sheet in order to apply the shaped adhesive beads in the appropriate position.

[0032] Furthermore, despite Figure 3 The illustration depicts adhesive beads 66 being applied to glass sheet 52 when it is in a curved configuration above chuck 68, but adhesive beads 66 can also be applied to glass sheet 52 when it is in a flat configuration, such that the glass sheet 52 with adhesive beads 66 applied is then curved above the forming surface 70 of chuck 68.

[0033] Figures 4A to 4D The steps in the process of achieving the desired aspect ratio of the adhesive beads 66 when bonding the frame 64 to the glass sheet 52 are described. Figures 4A to 4D The image shows only a portion of the glass sheet 52 and frame 64, specifically the portion of the glass sheet 52 and frame 64 where the adhesive beads 66 are adhered to a specific cross-section along the bead path. (See reference...) Figure 4A The adhesive bead 66 has a cross-section perpendicular to the bead path. In this embodiment, the cross-section of the adhesive bead 66 is substantially circular. In practice, the portion of the adhesive bead 66 in contact with the glass sheet 52 may be planarized, but the overall cross-sectional shape of the adhesive bead 66 is otherwise substantially circular.

[0034] like Figure 4AAs shown, the adhesive bead 66 has a first height H1, which is a dimension of the adhesive bead 66 perpendicular to the cross-section of the glass sheet 52. Further, the adhesive bead 66 has a first width W1, which is a dimension of the adhesive bead parallel to the cross-section of the glass sheet 52.

[0035] like Figure 4B As shown, frame 64 is lowered toward glass sheet 52 by press 72, thereby compressing adhesive beads 66. In doing so, the cross-section of adhesive beads 66 begins to change from a circle to a rounded rectangle or an bulging rectangle. According to this disclosure, adhesive beads 66 are compressed to a desired height by 10% to 50%, and then frame 64 is retracted to pull adhesive beads 66 back to the desired height. Therefore, as... Figure 4C As shown, the frame 64 moves toward the glass sheet 52 until the adhesive beads reach a second height H2 and a second width W2. In an embodiment, the second height H2 is half or less of the first height H1 (i.e., H2 ≤ 0.5 × H1). In an embodiment, the adhesive beads 66 are allowed to partially cure at the second height H2.

[0036] like Figure 4D As shown, the press 72 then retracts the frame 64 until the adhesive beads 66 reach a third height H3 and a third width W3. In an embodiment, the third height H3 is greater than the second height H2 (i.e., H3 > H2). In a specific embodiment, the second height H2 is 50% to 90% of the third height H3 (i.e., 0.5 × H3 ≤ H2 ≤ 0.9 × H3). Further, the third height H3 and the third width W3 are intended to be the final cured dimensions of the adhesive beads 66. The aspect ratio of the third height H3 to the third width W3 is at least 0.6 (i.e., H3 / W3 ≥ 0.6). In an embodiment, the aspect ratio of the third height H3 to the third width W3 can be 1.0 or greater, particularly up to 1.2. Therefore, in an embodiment, the aspect ratio of the height H3 to the width W3 is in the range of 0.6 to 1.2 (i.e., 0.6 ≤ H3 / W3 ≤ 1.2).

[0037] The frame 64 precisely compresses and retracts the adhesive beads 66 in various suitable manners. According to a first embodiment, the frame 64 is positioned at a second height H2 and a third height H3 using a press 72. That is, the press 72 has sufficient precision to position the frame 64 to compress the adhesive beads 66 to the desired second height H2 and retract the frame 64 to stretch the adhesive beads 66 to the desired third height H3. In another embodiment, the press 72 contacts a compliant stop 74. The pressure applied to the press 72 compresses the compliant stop 74 to the maximum compression corresponding to the second height H2 of the adhesive beads 66. After this, the pressure is released from the press 72, and the compliant stop 74 returns to the level corresponding to the third height H3 of the adhesive beads 66. This latter embodiment has the advantage that the press 72 does not need to be as precise in positioning the frame 64. In these or other feasible embodiments, the frame 64 is preferably capable of being positioned relative to the glass sheet 52 to produce the desired heights H2 and H3 of the adhesive beads 66 with an accuracy of 100 μm.

[0038] In this embodiment, the third height H3 is in the range of 0.5 mm to 2.0 mm, and the third width W3 is 2.0 mm or less. As described above, the third height H3 of the adhesive bead 66 relates to the distribution of shear stress generated by the uneven thermal expansion between the frame 64 and the glass sheet 52 during thermal cycling. Furthermore, the overall size of the bead ensures sufficient contact with the frame and the glass sheet 52 to provide reliable adhesion without contaminating adjacent parts or crowding the sides of the glass article 50.

[0039] exist Figure 4D As can be seen, the final cross-sectional shape of the adhesive bead 66 can be an hourglass shape, with a width at or near the center of the adhesive bead 66 smaller than the width of the adhesive bead 66 in contact with the glass sheet 52 and the frame 64. According to this disclosure, the aspect ratio of the adhesive bead 66 is determined relative to the widest width of its cross-section. In other embodiments, the final cross-sectional shape of the adhesive bead 66 is rectangular or bulging rectangular.

[0040] Figures 5A to 5B Cross-sectional views of adhesive beads 66 in their uncompressed state and in their final shape are depicted. Figure 5A The image shows uncompressed adhesive beads 66 deposited through a circular nozzle. The adhesive beads 66 have a first height H1 of 1.18 mm and a first width W1 of 1.36 mm. As described above, the contact area between the adhesive beads 66 and the glass sheet 52 creates a flat section, which resolves the difference between the first height H1 and the first width W1, but the adhesive beads 66 are also substantially circular. Figure 5B Depicting from such Figure 5AThe first height H1, shown as approximately 1.18 mm, is compressed to a second height H2 of approximately 0.8 mm, and then the frame 64 is retracted to provide adhesive beads 66 with a third height H3 of approximately 0.93 mm. The third width W3 is approximately 1.2 mm, which provides an aspect ratio of approximately 0.78.

[0041] Advantageously, the higher aspect ratio adhesive beads 66 according to this disclosure minimize the area required for adhesive on the glass (thus maximizing the display size) while maintaining an acceptable bead thickness to distribute shear stress caused by thermal cycling. The disclosed method also ensures reliable adhesive contact between the glass sheet 52 and the frame 64.

[0042] Having described a glass article 50 with adhesive beads 66 having a high aspect ratio, the following discussion provides the properties of embodiments of the glass sheet 52. Therefore, various geometrical properties, mechanical properties, and strengthening properties of the glass sheet 52, as well as the composition of the glass sheet 52, are provided in the following paragraphs.

[0043] In various embodiments, the average thickness T of the glass sheet 52 between the first main surface 54 and the second main surface 56 is in the range of 0.3 mm to 2 mm. In various embodiments, the width of the glass sheet 52 is in the range of 5 cm to 250 cm. Further, in various embodiments, the length of the glass sheet 52 is in the range of 5 cm to 1500 cm. This length is the maximum dimension of the glass sheet 52 perpendicular to the thickness T. This width is the maximum dimension of the glass sheet 52 perpendicular to both the thickness T and the length. In various embodiments, one or more radii of curvature of the glass sheet 52 (e.g., ...) Figures 2A to 2B The R shown is 75 mm to 10,000 mm.

[0044] In one or more embodiments, the glass sheet 52 may be strengthened to include compressive stress extending from the surface to the 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. In various embodiments, the glass sheet 52 may be mechanically strengthened by utilizing the mismatch in the coefficients of thermal expansion between different portions of the article to establish the compressive stress region and the central region exhibiting tensile stress. In some embodiments, the glass sheet may be thermally strengthened by heating the glass to a temperature above its glass transition point and then rapidly quenching it.

[0045] In other embodiments, the glass sheet 52 can be chemically strengthened by an ion exchange process. In this process, ions at or near the surface of the glass sheet are replaced or exchanged with larger ions having the same valence or oxidation state. In embodiments where the glass sheet comprises alkali aluminosilicate glass, the ions and larger ions in the surface layer of the article are monovalent alkali metal cations, such as Li. + Na + K + 、Rb + and Cs + Alternatively, monovalent cations in the surface layer can be replaced by substances such as Ag. + The substitution of monovalent cations other than alkali metal cations is performed. In these embodiments, the monovalent ions (or cations) exchanged into the glass sheet generate stress.

[0046] Ion exchange processes are typically carried out by immersing a glass sheet in a molten salt bath (or two or more molten salt baths) containing larger ions that are to be exchanged with smaller ions in the glass sheet. It should be noted that brine baths can also be used. Furthermore, the composition of the bath may include more than one type of larger ion (e.g., Na+). + and K + (or a single, larger ion). Those skilled in the art will understand that the parameters of an ion exchange process (including, but not limited to, bath composition and temperature, immersion time, number of immersions of the glass sheet in one or more salt baths, use of multiple salt baths, additional steps such as annealing, washing, etc.) are typically determined by the composition of the glass sheet (including the structure of the article and any crystalline phases present) and the desired DOC and compressive stress (CS) of the glass sheet resulting from strengthening. Exemplary molten bath compositions may include nitrates, sulfates, and chlorides of larger alkali metal ions. Typical nitrates include KNO3, NaNO3, LiNO3, NaSO4, and combinations thereof. The temperature of the molten salt bath is typically in the range from about 380°C to about 450°C, while the immersion time ranges from about 15 minutes to about 100 hours, depending on the glass sheet thickness, bath temperature, and glass (or monovalent ion) diffusivity. However, different temperatures and immersion times than those described above may also be used.

[0047] In one or more embodiments, the glass sheet may be immersed in a molten salt bath of 100% NaNO3, 100% KNO3, or a combination of NaNO3 and KNO3 at a temperature of about 370°C to about 480°C. In some embodiments, the glass sheet may be immersed in a molten mixed salt bath comprising about 5% to about 90% KNO3 and about 10% to about 95% NaNO3. In one or more embodiments, the glass sheet may be immersed in a first bath followed by a second bath. The first and second baths may have different compositions and / or temperatures. The immersion time in the first and second baths may vary. For example, the immersion in the first bath may be longer than the immersion in the second bath.

[0048] In one or more embodiments, the glass sheet may be immersed in a molten mixed salt bath comprising NaNO3 and KNO3 (e.g., 49% / 51%, 50% / 50%, 51% / 49%) at a temperature below about 420°C (e.g., about 400°C or about 380°C) for less than about 5 hours, or even about 4 hours or less.

[0049] Ion exchange conditions can be tailored to provide a “spike” or increase the slope of the stress profile at or near the surface of the resulting glass sheet. This spike can produce a larger surface CS value. Due to the unique properties of the glass composition used in the glass sheets described herein, this spike can be achieved through a single bath or multiple baths, wherein the single bath or multiple baths have a single composition or a mixture of compositions.

[0050] In one or more embodiments, when more than one type of monovalent ion is exchanged into the glass sheet, different monovalent ions can be exchanged to different depths within the glass sheet (and generate stresses of different magnitudes at different depths within the glass sheet). The relative depths of the resulting stress-generating ions can be determined, leading to different characteristics of the stress distribution.

[0051] CS can be measured using methods known in the art, such as surface stress meters (FSMs) using commercially available instruments, such as the FSM-6000 manufactured by Orihara Industrial Co., Ltd. of Japan. Surface stress measurement relies on the accurate measurement of the stress optical coefficient (SOC) associated with the birefringence of glass. SOC is then measured using methods known in the art, such as fiber bending and four-point bending methods (both described in ASTM standard C770-98 (2013) entitled “Standard Test Method for Measurement of Glass Stress-Optical Coefficient,” the contents of which are incorporated herein by reference in their entirety), and the bulk cylinder method.

[0052] DOC can be measured using a fractional light scintillation (FSM) or a supersonic optical scintillation (SCALP) microscope (such as the SCALP-04, available from Glassstress Ltd. in Tallinn, Estonia), depending on the strengthening method and conditions. When glass sheets are chemically strengthened by ion exchange treatment, either FSM or SCALP can be used depending on which ions are exchanged into the glass sheet. In cases where stress is generated in the glass sheet by exchanging potassium ions, FSM is used to measure DOC. In cases where stress is generated by exchanging sodium ions, SCALP is used to measure DOC. In cases where stress is generated in the glass sheet by exchanging both potassium and sodium ions, SCALP is used to measure DOC because the exchange depth of sodium is believed to indicate DOC, and the exchange depth of potassium ions indicates the magnitude of the change in compressive stress (but not the change from compressive stress to tensile stress); the exchange depth of potassium ions in these glass sheets is measured using FSM. CT is the maximum tensile stress and is measured using SCALP.

[0053] Suitable glass compositions for glass sheet 52 include soda-lime glass, aluminosilicate glass, borosilicate glass, borosilicate glass, alkali aluminosilicate glass, alkali borosilicate glass, and alkali borosilicate glass.

[0054] In one or more embodiments, the glass composition may include SiO2 in an amount ranging from about 66 mol% to about 80 mol%, Al2O3 in an amount ranging from about 4 mol% to about 15 mol%, B2O3 in an amount ranging from about 0 mol% to about 5 mol%, P2O5 in an amount ranging from about 0 mol% to about 2 mol%, R2O in an amount ranging from about 8 mol% to about 20 mol%, RO in an amount ranging from about 0 mol% to about 2 mol%, ZrO2 in an amount ranging from about 0 mol% to about 0.2 mol%, and SnO2 in an amount ranging from about 0 mol% to about 0.2 mol%. In the aforementioned composition, R2O refers to the total amount of alkali metal oxides such as Li2O, Na2O, K2O, Rb2O, and Cs2O. In particular, Na₂O may be present in an amount ranging from about 8 mol% to about 20 mol%, while K₂O may be present in an amount ranging from about 0 mol% to about 4 mol%. Further, in the aforementioned compositions, RO refers to the total amount of alkaline earth metal oxides such as CaO, MgO, BaO, ZnO, and SrO. Specifically, CaO may be present in an amount ranging from about 0 mol% to about 1 mol%, while MgO may be present in an amount ranging from about 0 mol% to about 7 mol%.

[0055] In embodiments, the glass composition may include oxides of other metals such as Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Ce, W, and Mo. In particular, Fe in the form of Fe₂O₃ may be present in an amount ranging from about 0 mol% to about 1 mol%, while TiO₂ may be present in an amount ranging from about 0 mol% to about 5 mol%.

[0056] An exemplary glass composition includes SiO2 in an amount ranging from about 65 mol% to about 75 mol%, Al2O3 in an amount ranging from about 8 mol% to about 14 mol%, Na2O in an amount ranging from about 12 mol% to about 17 mol%, K2O in an amount ranging from about 0 mol% to about 0.2 mol%, and MgO in an amount ranging from about 1.5 mol% to about 6 mol%. Optionally, SnO2 may be included in amounts further disclosed herein.

[0057] Aspect (1) of this disclosure relates to a glass article comprising: a frame including a frame support surface; a glass sheet including a first main surface and a second main surface, the second main surface being opposite to the first main surface; adhesive beads disposed between the frame support surface and the second main surface, the adhesive beads defining a bead path; wherein the adhesive beads have a cross-section perpendicular to the bead path, the cross-section including a width and a height; wherein the height is a maximum dimension perpendicular to the second main surface of the glass sheet, and the width is a maximum dimension parallel to the second main surface of the glass sheet; wherein the aspect ratio of the height to the width is at least 0.6; and wherein the width is 2 mm or less.

[0058] Aspect (2) of this disclosure relates to the glass article according to aspect (1), wherein the width is at least 0.5 mm.

[0059] Aspect (3) of this disclosure relates to the glass article according to aspect (1) or aspect (2), wherein the height is 0.5 mm to 2 mm.

[0060] Aspect (4) of this disclosure relates to a glass article according to any one of aspects (1) to (3), wherein the aspect ratio is at most 1.2.

[0061] Aspect (5) of this disclosure relates to a glass article according to any one of aspects (1) to (4), wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines an bulging rectangle.

[0062] Aspect (6) of this disclosure relates to a glass article according to any one of aspects (1) to (4), wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines a rectangle.

[0063] Aspect (7) of this disclosure relates to a glass article according to any one of aspects (1) to (4), wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines an hourglass shape.

[0064] Aspect (8) of this disclosure relates to a glass article according to any one of aspects (1) to (7), wherein the bead path is continuous between the frame support surface and the second main surface.

[0065] Aspect (9) of this disclosure relates to a glass article according to any one of aspects (1) to (7), wherein the bead path is discontinuous between the frame support surface and the second main surface.

[0066] Aspect (10) of this disclosure relates to a glass article according to any one of aspects (1) to (9), wherein the adhesive beads comprise polyurethane.

[0067] Aspect (11) of this disclosure relates to a glass article according to any one of aspects (1) to (10), wherein the adhesive beads have an elastic modulus in a cured state of 0.1 MPa to 300 MPa.

[0068] Aspect (12) of this disclosure relates to a glass article according to any one of aspects (1) to (11), wherein the first primary surface of the glass sheet comprises a curved surface with a radius of curvature of 75 mm to 10 m.

[0069] Aspect (13) of this disclosure relates to a glass article according to any one of aspects (1) to (12), wherein the first and second primary surfaces of the glass sheet define a thickness of 0.3 mm to 2.0 mm.

[0070] Aspect (14) of this disclosure relates to a method of forming a glass article, the glass article comprising a glass sheet having a first main surface and a second main surface, the second main surface being opposite to the first main surface; and a frame adhered to the glass sheet, the method comprising the following steps:

[0071] Adhesive beads are applied to a second main surface of a glass sheet or to a frame support surface of the frame in a bead path, the adhesive beads having a first height and a first width, the first height being perpendicular to the second main surface or the frame support surface on which the adhesive beads are applied, wherein the first width and the first height are perpendicular to the bead path; the adhesive beads are compressed to a second height and a second width between the second main surface of the glass sheet and the frame support surface; and the adhesive beads are expanded to a third height and a third width, wherein the third height is greater than the second height, and wherein the aspect ratio of the third height to the third width is at least 0.6.

[0072] Aspect (15) of this disclosure relates to the method according to aspect (14), wherein the step of applying the adhesive beads includes applying adhesive beads having a substantially circular cross-section.

[0073] Aspect (16) of this disclosure relates to the method according to aspect (14) or aspect (15), wherein the second height is 50% to 90% of the third height.

[0074] Aspect (17) of this disclosure relates to the method according to any one of aspects (14) to (16), wherein the third width is 0.5 mm to 2.0 mm.

[0075] Aspect (18) of this disclosure relates to the method according to any one of aspects (14) to (17), wherein the third height is 0.5 mm to 2.0 mm.

[0076] Aspect (19) of this disclosure relates to the method according to any one of aspects (14) to (18), wherein the aspect ratio is at most 1.2.

[0077] Aspect (20) of this disclosure relates to the method according to any one of aspects (14) to (19), wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines a rounded rectangle.

[0078] Aspect (21) of this disclosure relates to the method according to any one of aspects (14) to (20), wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines a rectangle.

[0079] Aspect (22) of this disclosure relates to the method according to any one of aspects (14) to (21), wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines an hourglass shape.

[0080] Aspect (23) of this disclosure relates to the method according to any one of aspects (14) to (22), wherein the step of applying the adhesive beads further comprises applying the adhesive beads to a second primary surface of the glass sheet while the glass sheet is in a flat configuration.

[0081] Aspect (24) of this disclosure, relating to the method according to any one of aspects (14) to (23), further includes the step of cold bending the first main surface of the glass sheet over a chuck.

[0082] Aspect (25) of this disclosure relates to the method according to any one of aspects (14) to (24), wherein the frame is held by a press, and wherein the step of compressing the adhesive beads further comprises pressing the frame over the adhesive beads until the second height is reached.

[0083] Aspect (26) of this disclosure relates to the method according to aspect (25), wherein the step of expanding the adhesive beads further includes retracting the press until the third height is reached.

[0084] Aspect (27) of this disclosure relates to the method according to aspect (26), wherein the press applies a first pressure to compress the compliant stop when the second height is reached.

[0085] Aspect (28) of this disclosure relates to the method according to aspect (27), wherein the press is reduced from the first pressure to the second pressure to reach the third height, such that the compliant stop is no longer compressed.

[0086] Aspect (29) of this disclosure relates to the method according to aspect (26), wherein the press automatically stops when it reaches the second height, and wherein, after retraction, the press holds the frame at the third height.

[0087] Aspect (30) of this disclosure relates to the method according to any one of aspects (14) to (29), wherein the adhesive beads comprise an adhesive having a viscosity of 1 kcps to 500 kcps in an uncured state.

[0088] Aspect (31) of this disclosure relates to a system for forming a glass article comprising a glass sheet adhered to a frame by adhesive beads, the system comprising: a chuck including a bending forming surface over which the glass sheet is bent; a press configured to position the frame above the glass sheet; and a nozzle configured to dispense the adhesive beads onto the glass sheet; wherein the press is configured to position the frame at a first height above the glass sheet to compress the adhesive beads; and wherein the press is configured to further position the frame at a second height above the glass sheet, the second height being greater than the first height.

[0089] Aspect (32) of this disclosure relates to the system according to aspect (31), wherein the nozzle has a circular port.

[0090] Aspect (33) of this disclosure relates to the system according to aspect (31) or aspect (32), wherein the press is configured to position the frame at the first height and at the second height with an accuracy of 100 μm.

[0091] Aspect (34) of this disclosure relates to the system according to any one of aspects (31) to (33), wherein the second height is 0.5 mm to 2.0 mm.

[0092] Aspect (35) of this disclosure relates to a system according to any one of aspects (31) to (34), wherein the first height is 50% to 90% of the second height.

[0093] Aspect (36) of this disclosure, relating to the system according to any one of aspects (31) to (35), further includes a compliant stop, wherein the press compresses the compliant stop until the frame reaches the first height, and wherein, after the frame reaches the first height, the press is released and the compliant stop is restored until the frame reaches the second height.

[0094] Aspect (37) of this disclosure relates to a system according to any one of aspects (31) to (36), wherein the chuck includes a plurality of vacuum channels at a plurality of ports terminating on the forming surface, and wherein vacuum pressure can be drawn through the vacuum channels to hold the glass sheet against the forming surface.

[0095] Aspect (38) of this disclosure relates to the system according to any one of aspects (31) to (37), wherein the shaped surface includes a radius of curvature of 75 mm or greater.

[0096] Unless otherwise expressly stated, it is not intended to interpret any method described herein as requiring its steps to be performed in a particular order. Therefore, no particular order is intended to be inferred unless a method claim actually describes the order in which the steps are followed or unless the claims or description specifically state that the steps are limited to a particular order. Furthermore, as used herein, the article “a(a)” is intended to include one or more parts or elements and is not intended to be construed as meaning only one.

[0097] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosed embodiments. Since modifications, combinations, sub-combinations, and variations in the spirit and substance of these embodiments will be apparent to those skilled in the art, the disclosed embodiments should be interpreted to include all matters within the scope of the appended claims and their equivalents.

Claims

1. A glass article comprising: The frame includes a frame support surface; A glass sheet, the glass sheet comprising a first main surface and a second main surface, the second main surface being opposite to the first main surface; Adhesive beads, the adhesive beads being disposed between the frame support surface and the second main surface, the adhesive beads defining a bead path; The adhesive beads have a cross-section perpendicular to the bead path, the cross-section including a width and a height; The height is the maximum dimension perpendicular to the second main surface of the glass sheet, and the width is the maximum dimension parallel to the second main surface of the glass sheet; wherein the aspect ratio of the height to the width is at least 0.6 and at most 1.2; and The width is 2 mm or less.

2. The glass article as claimed in claim 1, wherein the width is at least 0.5 mm.

3. The glass article as claimed in claim 1 or claim 2, wherein the height is from 0.5 mm to 2 mm.

4. The glass article according to any one of claims 1 to 2, wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines an bulging rectangle.

5. The glass article according to any one of claims 1 to 2, wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines a rectangle.

6. The glass article according to any one of claims 1 to 2, wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines an hourglass shape.

7. The glass article as claimed in any one of claims 1 to 2, wherein the bead path is continuous between the frame support surface and the second main surface.

8. The glass article as claimed in any one of claims 1 to 2, wherein the bead path is discontinuous between the frame support surface and the second main surface.

9. The glass article according to any one of claims 1 to 2, wherein the adhesive beads comprise polyurethane.

10. The glass article according to any one of claims 1 to 2, wherein the adhesive beads have an elastic modulus in the cured state of 0.1 MPa to 300 MPa.

11. The glass article according to any one of claims 1 to 2, wherein the first main surface of the glass sheet comprises a curved surface with a radius of curvature of 75 mm to 10 m.

12. The glass article according to any one of claims 1 to 2, wherein the first main surface and the second main surface of the glass sheet define a thickness of 0.3 mm to 2.0 mm.

13. A method for forming a glass article, the glass article comprising: A glass sheet, the glass sheet including a first main surface and a second main surface, the second main surface being opposite to the first main surface; and A frame, said frame being adhered to the glass sheet, the method comprising the following steps: Adhesive beads are applied to the second main surface of the glass sheet or to the frame support surface of the frame in the bead path. The adhesive beads have a first height and a first width, the first height being perpendicular to the second main surface or the frame support surface on which the adhesive beads are applied, wherein the first width and the first height are perpendicular to the bead path. The adhesive beads are compressed to a second height and a second width between the second main surface of the glass sheet and the frame support surface; and The adhesive beads are expanded to a third height and a third width, wherein the third height is greater than the second height, and wherein the aspect ratio of the third height to the third width is at least 0.6 and at most 1.

2.

14. The method of claim 13, wherein the step of applying the adhesive beads comprises applying adhesive beads having a substantially circular cross-section.

15. The method of any one of claims 13-14, wherein the second height is 50% to 90% of the third height.

16. The method of any one of claims 13-14, wherein the third width is from 0.5 mm to 2.0 mm.

17. The method of any one of claims 13-14, wherein the third height is 0.5 mm to 2.0 mm.

18. The method of any one of claims 13-14, wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines a rounded rectangle.

19. The method of any one of claims 13-14, wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines a rectangle.

20. The method of any one of claims 13-14, wherein the cross-sectional area of ​​the adhesive beads perpendicular to the bead path defines an hourglass shape.

21. The method of any one of claims 13-14, wherein the step of applying the adhesive beads further comprises applying the adhesive beads to the second primary surface of the glass sheet while the glass sheet is in a flat configuration.

22. The method of any one of claims 13-14, further comprising the step of cold bending the first main surface of the glass sheet over a chuck.

23. The method of any one of claims 13-14, wherein the frame is held by a press, and wherein the step of compressing the adhesive beads further comprises pressing the frame over the adhesive beads until the second height is reached.

24. The method of claim 23, wherein the step of expanding the adhesive beads further comprises retracting the press until the third height is reached.

25. The method of claim 24, wherein the press applies a first pressure to compress the compliant stop when the second height is reached.

26. The method of claim 25, wherein the press reduces from the first pressure to the second pressure to reach the third height, such that the compliant stop is no longer compressed.

27. The method of claim 24, wherein the press automatically stops when the second height is reached, and wherein, After retraction, the press holds the frame at the third height.

28. The method of any one of claims 13-14, wherein the adhesive beads comprise an adhesive having a viscosity of 1 kcps to 500 kcps in its uncured state.

29. A system for forming a glass article, the glass article comprising a glass sheet adhered to a frame by adhesive beads, the system comprising: A chuck, the chuck including a bending surface, wherein the glass sheet is bent above the bending surface; A press configured to position the frame above the glass sheet; A nozzle configured to dispense the adhesive beads onto the glass sheet; The press is configured to position the frame at a first height above the glass sheet to compress the adhesive beads; The press is configured to reposition the frame at a second height above the glass sheet, the second height being greater than the first height, and The adhesive beads define a bead path, the adhesive beads have a cross-section perpendicular to the bead path, the cross-section including a third width and a third height, wherein the aspect ratio of the third height to the third width is at least 0.6 and at most 1.

2.

30. The system of claim 29, wherein the nozzle has a circular port.

31. The system of any one of claims 29-30, wherein the press is configured to position the frame at the first height and at the second height with an accuracy of 100 μm.

32. The system of any one of claims 29-30, wherein the second height is 0.5 mm to 2.0 mm.

33. The system of any one of claims 29-30, wherein the first height is 50% to 90% of the second height.

34. The system of any one of claims 29-30, further comprising a compliant stop, wherein the press compresses the compliant stop until the frame reaches the first height, and wherein, After the frame reaches the first height, the press is released and the compliant stop is restored until the frame reaches the second height.

35. The system of any one of claims 29-30, wherein the chuck includes a plurality of vacuum channels at a plurality of ports terminating on the forming surface, and wherein vacuum pressure can be drawn through the vacuum channels to hold the glass sheet against the forming surface.

36. The system of any one of claims 29-30, wherein the shaped surface comprises a radius of curvature of 75 mm or greater.

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