Glass article, display device, method for manufacturing glass article, and method for manufacturing display device

Abstract

The present invention suppresses a deviation between a cover glass and a desired shape. A glass article (10) according to the present invention is provided with: a cover glass (12) that is heat-molded and has a bent section (20); a frame (14) provided on the main surface (12B) of the cover glass (12); and an adhesive layer (16) which is provided between the main surface (12B) of the cover glass (12) and the frame (14), and which adheres the cover glass (12) and the frame (14), and wherein the parameter A described in the specification is greater than 0 and 0.5 or less.

Description

Technical Field

[0001] The present invention relates to a glass article, a display device, a method for manufacturing a glass article, and a method for manufacturing a display device. Background Art

[0002] In vehicle-mounted display devices that display information required during operation, liquid crystal displays and organic EL displays are sometimes used. In these displays, a cover glass is sometimes configured to protect the front surface. In addition, in recent years, high design is required for the decoration inside the vehicle, and a cover glass with a curved surface shape is required. For example, Patent Document 1 describes a display device having a protective component as a cover glass, a frame, and a display panel. In addition, a method of heat forming is known in which the cover glass is heated while being bent in order to bend the cover glass.

[0003] Patent Document 1: Japanese Patent No. 6941930

[0004] However, when the cover glass is bent by, for example, heat forming, etc., there may be a deviation between the shape of the cover glass and the desired curved shape. Therefore, it is required to suppress the deviation between the cover glass and the desired shape. Summary of the invention

[0005] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a glass article, a display device, a method for manufacturing a glass article, and a method for manufacturing a display device, which can suppress deviation between a cover glass and a desired shape.

[0006] The glass article involved in the present disclosure comprises: a cover glass that is heat-formed and includes a curved portion; a frame that is arranged on the main surface of the above-mentioned cover glass; and an adhesive layer that is arranged between the main surface of the above-mentioned cover glass and the above-mentioned frame so that the above-mentioned cover glass and the above-mentioned frame are bonded, and the parameter A specified by the following formula (1) is greater than 0 and is less than 0.5.

[0007]

[0008] Here, E1 is the Young's modulus of the cover glass (GPa), t1 is the thickness of the cover glass (mm), E2 is the Young's modulus of the frame (GPa), and I2 is the section moment of inertia of the frame (mm 4 ), E3 is the elastic modulus of the adhesive layer (MPa), and W is the area of ​​the adhesive layer (cm 2 ) divided by the length (cm) along the main surface of the above-mentioned bent portion in a direction perpendicular to the bending axis.

[0009] The display device according to the present disclosure includes a display and the glass article provided on the surface of the display.

[0010] The method for manufacturing a glass article according to the present disclosure includes the steps of: forming a cover glass including a curved portion by bending a glass plate while heating it; and bonding a main surface of the cover glass to a frame via an adhesive layer to manufacture the glass article.

[0011] The method for manufacturing a display device according to the present disclosure includes the step of mounting the above-mentioned glass article on a display to manufacture the display device.

[0012] According to the present invention, it is possible to suppress deviation of the cover glass from a desired shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram showing a display device according to this embodiment.

[0014] Figure 2 It is a schematic diagram of the glass article involved in this embodiment.

[0015] Figure 3A It is a top view of the cover glass.

[0016] Figure 3B yes Figure 3A AA section view.

[0017] Figure 4 is a cross-sectional view of a glass article including a cover glass.

[0018] Figure 5 It is a schematic diagram for explaining the manufacturing method of the glass article and the display device according to the present embodiment.

[0019] Figure 6 This is a diagram showing an example of providing a plurality of adhesive layers.

[0020] Figure 7 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0021] Figure 8 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0022] Fig. 9 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0023] Fig.10 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0024] Fig.11 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0025] Fig.12 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0026] Fig.13 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0027] Fig.14 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0028] Fig.15 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0029] Fig.16 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0030] Fig.17 It is a schematic diagram of a cover glass according to another example of the present embodiment.

[0031] Fig.18 It is a schematic diagram of a cover glass according to another example of the present embodiment. DETAILED DESCRIPTION

[0032] Hereinafter, the preferred embodiment of the present invention will be described in detail with reference to the attached drawings. In addition, the present invention is not limited to the embodiment, and in the case where there are multiple embodiments, it also includes an embodiment composed of a combination of the embodiments. In addition, for numerical values, the range of rounding is included.

[0033] (Display device)

[0034] Figure 1 Schematic diagram showing a display device according to this embodiment. Figure 1 As shown, the glass article 10 involved in this embodiment is provided in the display device 2 and is used as a cover material of the surface (front surface) of the display 3 that displays an image. The display device 2 in this embodiment is a vehicle-mounted display device provided in a vehicle, for example, provided in front of the steering shaft 1 in the vehicle. The display 3 displays, for example, a car navigation screen, various instruments such as a speedometer, and a start button. However, Figure 1 The structure of is an example, and the display device 2 using the glass article 10 can have any structure. In addition, the glass article 10 is not limited to being used as a cover material for the surface of the display device 2, and can also be used for any purpose.

[0035] (Glass Items)

[0036] Figure 2 Schematic diagram of the glass article involved in this embodiment. Figure 2 As shown, the glass article 10 includes a cover glass 12, a frame 14, and an adhesive layer 16. The cover glass 12 is a transparent plate-shaped glass component, and has a main surface on one side, that is, a main surface 12A (first main surface) and a main surface on the opposite side of the main surface 12A, that is, a main surface 12B (second main surface). When the glass article 10 is mounted on a mounted object such as a display device 2, the main surface 12A becomes the side exposed to the outside, and the main surface 12B becomes the side facing the mounted object (here, the display 3). In addition, the transparency here refers to the permeability with respect to visible light.

[0037] (frame)

[0038] The frame 14 is a frame-shaped component attached to the main surface 12B of the cover glass 12. The frame 14 is made of, for example, resin, metal, or fiber-reinforced plastic, but is not limited thereto and may be any material. The cover glass 12 is curved in the X direction (described later), and the frame 14 is also curved in the X direction along the cover glass 12. The frame 14 is attached to the peripheral edge of the main surface 12B of the cover glass 12. Figure 2 In the example of FIG. 1 , the frame 14 is in the shape of a frame (frame) provided over the entire section in the circumferential direction of the peripheral edge portion of the main surface 12B of the cover glass 12. Figure 2 In the example, although the end of the peripheral side of the cover glass 12 does not extend from the frame 14, it is not limited to this, and the end of the peripheral side of the cover glass 12 may also extend from the frame 14. In addition, the shape of the frame 14 and the installation position of the frame 14 on the main surface 12B are not limited to the above description, and may be arbitrary. For example, the frame 14 may be a shape that is interrupted in a portion of the circumferential direction of the peripheral portion of the main surface 12B. That is, for example, in the case where the main surface 12B is a shape formed by bending a rectangle, the frame 14 may be a shape that is set on three of the four sides of the rectangle, or a shape that is set on two opposite sides, or a shape that is set on one side.

[0039] (Adhesive layer)

[0040] The frame 14 is fixed (bonded) to the main surface 12B of the cover glass 12 via the adhesive layer 16. The adhesive layer 16 is provided between the frame 14 and the main surface 12B of the cover glass 12, and bonds the surface of the frame 14 on the cover glass 12 side to the main surface 12B of the cover glass 12. The adhesive layer 16 can be composed of any adhesive member capable of bonding the frame 14 to the cover glass 12, such as a double-sided tape or an adhesive.

[0041] (Cover glass)

[0042] The cover glass 12 is bent and mounted on the frame 14. In the present embodiment, the cover glass 12 is heat-formed to a desired shape. The cover glass 12 is mounted on the frame 14 in such a manner that a flat glass plate is bent by a heat forming method (thermoforming method), and the cover glass 12 in a bent state is bent and mounted on the frame 14 without further heating. That is, the cover glass 12 bent by heat forming is mounted on the frame 14 in a state where bending stress is applied by bending accompanied by elastic deformation by an external force without further heating. In addition, heat forming here refers to a method of bending by raising the temperature of the glass to above the glass transition temperature.

[0043] Hereinafter, the shape of the cover glass 12 will be described in more detail. Figure 3A is a top view of the cover glass. Figure 3B yes Figure 3A AA section view, Figure 4 is a cross-sectional view of a glass article including a cover glass. Figure 3A In the example of , the cover glass 12 is a rectangular flat glass plate bent. Hereinafter, one side (end face) of the cover glass 12 is referred to as the side face 12C1, the side face opposite to the side face 12C1 is referred to as the side face 12C2, the other side face of the cover glass 12 is referred to as the side face 12C3, and the side face opposite to the side face 12C3 is referred to as the side face 12C4. Figure 3A In the example, the side surfaces 12C1 and 12C2 are the short sides of the rectangle, and the side surfaces 12C3 and 12C4 are the long sides of the rectangle. In addition, the cover glass 12 is not limited to the shape formed by bending a rectangular flat glass plate, but can be a shape formed by bending a glass plate of any shape. For example, the cover glass 12 can also be a shape formed by bending a polygonal, circular, or elliptical flat glass plate.

[0044] Figure 3A This is a diagram when the cover glass 12 is viewed from the normal direction (Z direction) of a position P on the main surface 12B of the cover glass 12. Figure 4 : represents a cross section of the cover glass 12 along the X direction. Here, the tangent direction selected so as to satisfy the following conditions among the tangent directions of the main surface 12B of the cover glass 12 at an arbitrary point P is set as the X direction (first direction), the direction orthogonal to the X direction among the tangent directions of the main surface 12B at the point P is set as the Y direction, and the direction orthogonal to the X direction and the Y direction, that is, the normal direction (thickness direction) of the position P is set as the Z direction. Here, the X direction refers to the direction in which the radius of curvature of a line formed by a plane including the tangent direction and the normal direction intersecting the main surface 12B among the tangent directions of the main surface 12B at an arbitrary point P of the cover glass 12 becomes the smallest.

[0045] Since the cover glass 12 of this embodiment is uniaxially curved, the X direction can be clearly defined regardless of which point the position P is taken. Fig.16 , Fig.17 ), there is also a case where a plurality of curved portions 20 are provided and the bending directions of the respective curved portions 20 intersect. In this case, it is sufficient to define the X direction for each curved portion 20. That is, the direction in which the radius of curvature of a line formed by a plane including the tangent direction and the normal direction intersecting the principal surface 12B in the tangent direction of a position P on one curved portion 20 becomes the smallest can be defined as the X direction of the curved portion 20, and the X direction can be defined similarly for each curved portion 20.

[0046] When there are multiple tangent directions in which the curvature radius of a line formed by a plane including the tangent direction and the normal direction intersecting the main surface 12B becomes the smallest, at least one of the tangent directions may be determined as the X direction.

[0047] like Figure 4 As shown, when the cover glass 12 is mounted on the frame 14, the cover glass 12 is bent with a radius of curvature R, with the Y direction as the bending axis and the X direction as the direction orthogonal to the bending axis. The radius of curvature R can also be said to be the radius of curvature of a line formed by the intersection of a plane including the X direction and the Z direction and the main surface 12B. The radius of curvature R of the cover glass 12 (the radius of curvature of the bend with the Y direction as the bending axis) is preferably greater than 100 mm and less than 8000 mm, more preferably greater than 300 mm and less than 6000 mm, and further preferably greater than 500 mm and less than 4000 mm. By making the radius of curvature R within this range, the design can be improved and the deviation between the cover glass 12 in the glass article and the desired shape can be suppressed.

[0048] In addition, the curvature radius of the cover glass 12 with the Y direction as the bending axis in the state where the cover glass 12 is removed from the frame 14 is set as the curvature radius R1. The curvature radius R1 can also be said to be the curvature radius of the line formed by the plane including the X direction and the Z direction and the main surface 12B intersecting in the state where the cover glass 12 is removed from the frame 14. In this case, the curvature radius R1 of the cover glass 12 is preferably 50 mm or more and 10000 mm or less, more preferably 100 mm or more and 8000 mm or less, and further preferably 300 mm or more and 6000 mm or less. By making the curvature radius R1 within this range, the design can be improved and the deviation between the cover glass 12 in the glass article and the desired shape can be suppressed. Among them, the curvature radius R1 refers to the curvature radius of the cover glass 12 in the state where the cover glass 12 is removed from the frame 14 and is not subjected to a load from the outside and is not elastically deformed due to an external load. Since the cover glass 12 is heat-formed in this manner, it is curved even in a state where the cover glass 12 is removed from the frame 14 and is not elastically deformed.

[0049] In more detail, the cover glass 12 is bent by heat-forming the glass plate to a desired shape before being attached to the frame 14. At this time, the absolute value of the difference between the radius of curvature R1 of the cover glass 12 in a state where the cover glass 12 is removed from the frame 14 and the radius of curvature R of the cover glass 12 in a state where the cover glass 12 is attached to the frame 14 is preferably 5% or less of the radius of curvature R, and more preferably 2% or less. That is, the cover glass 12 in the present embodiment is preferably bent to a radius of curvature close to the final radius of curvature R by heat-forming, thereby, by satisfying the formula (1) described later, it is easy to suppress the deviation between the cover glass in the glass article and the desired shape.

[0050] On the other hand, the absolute value of the difference between the radius of curvature R1 and the radius of curvature R is, for example, greater than 0.0%, and is equal to or greater than 0.2%. In the heat forming method, in particular, in the self-weight forming method in which a glass plate is placed on a lower mold and heated, and the glass plate is bent by its own weight, even when the glass plate is bent to a desired shape, the shape sometimes deviates. According to the present embodiment, even in such a case, when the glass plate is mounted on the frame 14 as the cover glass 12 to manufacture the glass article, the deviation of the cover glass 12 from the desired shape can be suppressed.

[0051] Furthermore, if the curvature radius of the frame 14 in the state where the cover glass 12 is removed from the frame 14 is set to R3, the curvature radius R3 (the curvature radius of the bend with the Y direction as the bending axis) is preferably 100 mm or more and 8000 mm or less, more preferably 300 mm or more and 6000 mm or less, and further preferably 500 mm or more and 4000 mm or less. The absolute value of the difference between the curvature radius R3 and the curvature radius R of the cover glass 12 in the state where the cover glass 12 is attached to the frame 14 is preferably 2% or less, more preferably 1% or less. Since the curvature radius R3 is within the above range, it is easy to suppress the deviation between the cover glass in the glass article and the desired shape.

[0052] The cover glass 12 is preferably not curved in directions other than the curvature direction with the Y direction as the curvature axis. The cover glass 12 is preferably not curved with the X direction as the curvature axis. In other words, the track along the Y direction on the main surface 12B of the cover glass 12 is preferably a straight line. The absence of curvature is not limited to an infinite radius of curvature, and may also include a case where the radius of curvature is greater than 10000 mm.

[0053] Hereinafter, the portion of the cover glass 12 that is curved with the Y direction as the bending axis is referred to as the curved portion 20. The curved portion 20 refers to a region of the cover glass 12 that is curved with the Y direction as the bending axis and with the same curvature radius R. That is, the curved portion 20 of the cover glass 12 can be said to be curved with the curvature radius R and with the Y direction as the bending axis. Figure 4 In the example of FIG. 2 , since the entire cover glass 12 is curved in the X direction with the same curvature radius R, it can be said that the entire cover glass 12 forms the curved portion 20 .

[0054] The same curvature radius R here does not mean that the curvature radius R at each position is strictly the same. For example, if the change in the curvature radius R measured at each position from the end point on one side to the end point on the other side in the X direction of the region curved with the Y direction as the bending axis on the main surface 12B of the cover glass 12 is 5% or less, that is, the difference between the maximum value and the minimum value of the curvature radius R at each position is 5% or less of the maximum value of the curvature radius R at each position, then the region is regarded as a region with the same curvature radius and is treated as one curved portion 20. In addition, the average value of the curvature radius R at each position of the curved portion 20 can be treated as the curvature radius R of the curved portion 20.

[0055] Examples of a method for measuring the radius of curvature R and the radius of curvature R1 of the cover glass 12 include a method of measuring the shape using a contact or non-contact three-dimensional measuring machine and obtaining the shape from shape data, and a method of measuring by pressing an R gauge against the cover glass 12 .

[0056] In the present embodiment, the curved portion 20 is curved so as to be convex toward the principal surface 12A side. However, the curved portion 20 is not limited to being curved so as to be convex toward the principal surface 12A side, and may be curved so as to be convex toward the principal surface 12B side.

[0057] In addition, the arbitrary point P mentioned above is an arbitrary point in the curved portion 20 of the main surface 12B, and for example, when the central area of ​​the main surface 12A is the curved portion 20, it may be the central position of the main surface 12B (for example, the center of gravity of the cover glass 12). That is, the X direction and the Y direction may be the tangent direction from the center of the main surface 12B, and the Z direction may be the normal direction at the center of the main surface 12B.

[0058] (Material of cover glass)

[0059] Although the material of the glass used for the cover glass 12 is arbitrary, for example, alkali-free glass, soda-lime glass, soda-lime silicate glass, aluminosilicate glass, borosilicate glass, lithium aluminosilicate glass, borosilicate glass, etc. can be used. In addition, the cover glass 12 is preferably chemically strengthened, in other words, it is preferred to have a compressive stress layer on the surface. Therefore, as the cover glass 12, aluminosilicate glass and lithium aluminosilicate glass are preferably used, which can easily withstand large stresses through strengthening treatment even if the thickness is thin, and high-strength glass can be obtained even if it is thin. In addition, the chemical strengthening treatment is usually performed by immersing the glass in a molten salt containing an alkali metal.

[0060] The cover glass 12 preferably contains 50% to 80% SiO2, 0.1% to 25% Al2O3, 3% to 30% Li2O+Na2O+K2O, 0 to 25% MgO, 0 to 25% CaO, and 0 to 5% ZrO2, based on the molar percentage of the oxide, but is not particularly limited. In addition, the 50% to 80% here means that the molar percentage of the total amount of the cover glass 12 is set to 100%, which is 50% or more and 80% or less, and the same applies to other numerical ranges. In addition, Li2O+Na2O+K2O refers to the total content of Li2O, Na2O, and K2O. By setting the cover glass 12 to the following composition, the rigidity can be appropriately maintained even when the cover glass 12 is bent. Among them, the numerical range represented by "~" means a numerical range that includes the numerical values ​​before and after ~ as the lower limit and upper limit, and the same meaning is also meant when "~" is used below.

[0061] More specifically, as a more preferable composition of the glass for the cover glass 12, the following glass compositions can be cited. For example, "containing 0 to 25% of MgO" means that MgO is not essential, but it can be contained up to 25%. The glass of (i) is contained in soda-lime silicate glass, the glasses of (ii) and (iii) are contained in aluminosilicate glass, and the glasses of (iv), (v) and (vi) are contained in lithium aluminosilicate glass.

[0062] (i) Glass comprising, in terms of composition expressed in mol%, 63% to 73% SiO2, 0.1% to 5.2% Al2O3, 10% to 16% Na2O, 0% to 1.5% K2O, 0% to 5.0% Li2O, 5% to 18% MgO and 1% to 10% CaO

[0063] (ii) Glass having a composition expressed in mol %, comprising 50% to 74% SiO2, 5% to 15% Al2O3, 10% to 20% Na2O, 0% to 8% K2O, 0% to 5.0% Li2O, 2% to 15% MgO, 0% to 6% CaO and 0% to 5% ZrO2, wherein the total content of SiO2 and Al2O3 is 65% to 85%, the total content of Na2O and K2O is 12% to 25%, and the total content of MgO and CaO is 1% to 15%

[0064] (iii) Glass containing, in terms of composition expressed in mol%, 68% to 80% of SiO2, 4% to 10% of Al2O3, 5% to 15% of Na2O, 0% to 1% of K2O, 0% to 5.0% of Li2O, 4% to 15% of MgO and 0% to 1% of ZrO2

[0065] (iv) Glass containing, in terms of a composition expressed in mol%, 67% to 75% of SiO2, 0% to 4% of Al2O3, 7% to 15% of Na2O, 1% to 9% of K2O, 0% to 5.0% of Li2O, 6% to 14% of MgO and 0% to 1.5% of ZrO2, wherein the total content of SiO2 and Al2O3 is 71% to 75%, the total content of Na2O and K2O is 12% to 20%, and when CaO is contained, the content of CaO is less than 1%

[0066] (v) Glass containing, in terms of a composition expressed in mol%, 50% to 73% SiO2, 5% to 20% Al2O3, 0% to 6% B2O3, 0% to 10% P2O5, 4% to 12% Li2O, 3% to 20% Na2O, 0% to 5% K2O, 0% to 8% MgO, 0% to 2% CaO, 0% to 5% SrO, 0% to 5% BaO, 0% to 5% ZnO, 0% to 2% TiO2, and 0% to 4% ZrO2

[0067] (vi) Glass containing, in terms of a composition expressed in mol%, 58% to 80% SiO2, 13% to 18% Al2O3, 0% to 5% B2O3, 0.5% to 4% P2O5, 3% to 10% Li2O, 5% to 20% Na2O, 0% to 2% K2O, 0% to 11% MgO, 0% to 20% CaO, 0% to 20% SrO, 0% to 15% BaO, 0% to 10% ZnO, 0% to 1% TiO2, and 0% to 2% ZrO2

[0068] (Parameter A of glass objects)

[0069] Here, when trying to bend a glass sheet by heat forming to obtain a desired curved shape, the shape sometimes deviates from the desired curved shape. In contrast, in the present embodiment, the glass sheet is heat formed to be bent to a certain extent, and then it is mounted on a frame 14 to be further bent to manufacture a glass article, thereby suppressing the deviation between the cover glass 12 and the desired curved shape. In addition, the inventors have found that by designing the parameter A specified as described below to a specified numerical range, the deviation from the desired curved shape can be appropriately suppressed. That is, in the present embodiment, by specifying the parameter A of the glass article 10 as follows, the deviation from the desired curved shape can be appropriately suppressed. Parameter A is described below.

[0070] In the glass article 10, the parameter A represented by the following formula (1) is less than 0.5, preferably less than 0.3, and more preferably less than 0.1. By making the parameter A within this range, the deviation from the desired curved shape can be appropriately suppressed. In addition, it can be said that the parameter A is greater than 0, preferably greater than 0.001, more preferably greater than 0.005, and further preferably greater than 0.01. That is, the parameter A is greater than 0 and less than 0.5, preferably greater than 0.001 and less than 0.5, more preferably greater than 0.005 and less than 0.3, and further preferably greater than 0.01 and less than 0.1. By setting the parameter A to less than 0.5, preferably less than 0.3, and more preferably less than 0.1, the value PV to be described later can be set to less than 0.5, and the deviation from the desired curved shape can be appropriately suppressed, so it is preferred.

[0071] In addition, the value PV of the glass article 10 in this embodiment is calculated by the following assumption. First, it is assumed that the glass article 10 and the glass article having a desired curved shape are placed on a horizontal plane without applying an external force. In this state, the distance in the vertical direction is calculated for the portion where the two shapes overlap and a deviation occurs, and the maximum value in the entire area is set as the value PV.

[0072] At this time, the glass object is assumed to be set so that the convex surface appears on the horizontal plane side. When the glass object has both a convex surface and a concave surface, the larger value of the vertical distance calculated by setting one surface to the horizontal plane side and the vertical distance calculated by setting the other surface to the horizontal plane side is used as the value PV.

[0073]

[0074] here,

[0075] E1 is the Young's modulus of the cover glass 12 (GPa),

[0076] t1 is the thickness of the cover glass 12 (mm),

[0077] E2 is the Young's modulus of the frame 14 (GPa),

[0078] I2 is the section inertia moment of the frame 14 (mm 4 ),

[0079] E3 is the elastic modulus of the adhesive layer 16 (MPa),

[0080] As shown in the following formula (2), W is the area B (cm 2 ) divided by the length L (cm) of the bending portion 20 in a direction perpendicular to the bending axis. The area B and the length L will be described later.

[0081] However, Σ(E3W) in the formula (1) is obtained when a plurality of adhesive layers 16 are provided as described later (for example, Figure 6 ) is the total value of (E3W) of each adhesive layer 16. When there is one adhesive layer 16, Σ(E3W) is the (E3W) of this one adhesive layer 16.

[0082] W=B / L…(2)

[0083] Thus, it can be said that by setting the Young's modulus E1 and thickness t1 of the cover glass 12, the Young's modulus E2 and the moment of inertia I2 of the frame 14, the elastic modulus E3 of the adhesive layer 16, and the value W (the area B of the adhesive layer 16 and the length L of the curved portion 20) so that the parameter A falls within the above range, it is possible to suppress the deviation from the desired curved shape. 2 It is a parameter representing the rigidity of the cover glass 12. In order to suppress the deviation from the desired curved shape, that is, to reduce parameter A, it can be said that the lower the value, the more preferred. On the other hand, E2I2 in formula (1) is a parameter representing the rigidity of the frame 14. The higher the value, the easier it is to correct the deviation between the cover glass 12 and the desired curved shape. Therefore, in order to suppress the deviation from the desired curved shape, it can be said that the higher the value, the more preferred. Similarly, for the elastic modulus E3 of the adhesive layer 16, the higher its value, the easier it is to transfer the correction of the frame 14 to the cover glass 12. For W, the higher its value, the wider the correction of the frame 14 is applied to the cover glass 12. Therefore, in order to suppress the deviation from the desired curved shape, it can be said that the higher these values, the more preferred.

[0084] Hereinafter, each parameter defined by equations (1) and (2) will be described.

[0085] (Young's modulus E1 of cover glass)

[0086] The Young's modulus E1 of the cover glass 12 is preferably 60 GPa to 90 GPa, more preferably 68 GPa to 78 GPa, and further preferably 72 GPa to 76 GPa. By setting the Young's modulus E1 within this range, deviation from a desired curved shape can be appropriately suppressed.

[0087] In addition, the Young's modulus E1 of the cover glass can be measured by a resonance method, a mechanical test method, and an ultrasonic pulse method. The resonance method is a method of applying vibration to the test piece and measuring the natural frequency, and calculating the Young's modulus based on the natural frequency. The mechanical test method is a method of applying a load such as tension to the test piece, and calculating the Young's modulus based on the deformation and load caused by it. The ultrasonic pulse method is a method of propagating an ultrasonic pulse through the test piece and measuring it based on its propagation speed. In general, for the Young's modulus of glass, it is known that the additive law holds true, and it can also be calculated by performing multiple regression based on the Young's modulus of multiple glass compositions.

[0088] (Thickness t1 of cover glass)

[0089] The thickness t1 of the cover glass 12 is preferably 0.1 mm to 3.0 mm, more preferably 0.4 mm to 1.5 mm, and further preferably 0.7 mm to 1.4 mm. By making the thickness t1 within this range, the deviation from the desired curved shape can be appropriately suppressed. Figure 4 As shown in FIG. 1 , the thickness t1 refers to the distance in the Z direction from the main surface 12A to the main surface 12B.

[0090] (Young's modulus E2 of the frame)

[0091] The Young's modulus E2 of the frame 14 is preferably 1 GPa or more and 400 GPa or less, more preferably 2 GPa or more and 250 GPa or less, further preferably 40 GPa or more and 230 GPa or less, further preferably 60 GPa or more and 210 GPa or less. By setting the Young's modulus E2 within this range, the rigidity of the frame 14 can be ensured, and the deviation of the cover glass 12 from the desired curved shape can be appropriately suppressed.

[0092] In addition, the Young's modulus E2 of the frame can be measured by a resonance method, a mechanical test method, an ultrasonic pulse method, or the like, similarly to the Young's modulus E1.

[0093] (Frame section moment of inertia I2)

[0094] The cross-sectional inertia moment I2 of the frame 14 is preferably 0.1 mm 4 Above and 1250mm 4 Below, more preferably 1mm 4 Above and 450mm 4 Below, more preferably 1.5 mm 4 Above and 30mm 4 By making the section inertia moment I2 within this range, the rigidity of the frame 14 can be ensured without significantly compromising the design, and the deviation from the desired bending shape can be appropriately suppressed. The section inertia moment is assumed to be relative to the bending axis. Figure 3A In the example, the bending axis is the Y axis. Figure 3A A cross-sectional view of the glass article 10 at the AA section (a plane perpendicular to the X-axis) is shown in FIG. Figure 3B .also, Figure 3B For the sake of convenience, the figure is set to assume that the glass article 10 is not bent. In this case, the cross-sectional inertia moment I2 of the frame 14 is as follows: Figure 3B In this way, in the AA section (plane perpendicular to the X-axis), the area FA of the frame 14 in the plane perpendicular to the X-axis is used to calculate the area FA of the frame 14 in the plane perpendicular to the X-axis. 2More specifically, the cross-sectional inertia moment I2 of the frame 14 is obtained by integrating the square value of the thickness t of the frame 14. When the length of the frame 14 along the main surface in the direction perpendicular to the bending axis (here, the X direction) is L, FA In the case of, it can be calculated by the following formula (3). That is, in this embodiment, the average value of the cross-sectional inertia moment of each position of the frame 14 along the direction of the bending axis is set to the cross-sectional inertia moment I2 of the frame 14. Among them, the distance between the positions when calculating the average value of the cross-sectional inertia moment of each position along the direction of the bending axis and the number of positions used in the calculation of the average value can be arbitrary.

[0095]

[0096] (Elastic modulus E3 of adhesive layer)

[0097] The elastic modulus E3 of the adhesive layer 16 is preferably 0.2 MPa or more and 100 MPa or less, more preferably 1 MPa or more and 50 MPa or less, and further preferably 5 MPa or more and 35 MPa or less. By making the elastic modulus within this range, the cover glass 12 can be properly bonded to the frame 14, and the shape of the cover glass 12 can properly follow the shape of the frame 14, thereby appropriately suppressing the deviation of the cover glass 12 from the desired curved shape.

[0098] The elastic modulus E3 of the adhesive layer 16 can be measured by the following indentation elastic modulus test.

[0099] The adhesive layer 16 bonded to the main surface 12B of the cover glass 12 is exposed toward the upper side in the vertical direction and is arranged on a creep meter (for example, manufactured by Yaden, model RE2-33005C). A plunger (cylindrical plunger manufactured by Yaden, model P-61, φ1.5, H40) is pressed into the adhesive layer 16 at a speed of 0.05 mm / sec at room temperature (for example, 20°C) until the pressing depth becomes 5% to 10% of the thickness of the adhesive layer 16. The load acting on the plunger after the pressing and the displacement in the pressing direction of the plunger are measured in sequence, and the load and displacement are plotted in units of time. The slope of the approximate line of each point of the plot is calculated as the elastic modulus of the adhesive layer 16. In addition, the press-in elastic modulus test of the present invention is a parameter indicating the adhesive strength. As an existing adhesive strength test, although a cross adhesive strength test is known, this method is difficult to measure due to the state of the glass article. The above-mentioned indentation elastic modulus test can verify even a glass article in a state where the cover glass and the frame are bonded together, and also obtains a correlation with the bonding strength observed in the conventional bonding strength test.

[0100] (Area B of adhesive layer)

[0101] The area B of the adhesive layer 16 is as follows: Figure 3A The area shown is the area of ​​the adhesive region AR, which is the area overlapping the adhesive layer 16 in the entire area of ​​the main surface 12B of the curved portion 20. The area B of the adhesive layer 16 is preferably 50 cm 2 Over 1700cm 2 Below, more preferably 100cm 2 Over 1400cm 2 Below, more preferably 200cm 2 Over 1100cm 2 By making the area B within this range, it is possible to suppress the deterioration of the design due to the excessively large adhesion area AR, and to make the cover glass 12 appropriately adhere to the frame 14, so that the shape of the cover glass 12 appropriately follows the shape of the frame 14, thereby appropriately suppressing the deviation of the cover glass 12 from the desired curved shape. In the case where a plurality of adhesive layers 16 are provided, the area B of the adhesive layer 16 refers to the area of ​​one adhesive layer 16 among the plurality of adhesive layers 16.

[0102] In addition, if the area that does not overlap with the adhesive layer 16 in the entire area of ​​the main surface 12B of the curved portion 20 is defined as the area AR0, the adhesive area AR is formed radially outside the area AR0 when the axis passing through the center position of the curved portion 20 along the Z direction is defined as the axial direction. In the present embodiment, since the entire cover glass 12 constitutes the curved portion 20, the area that overlaps with the adhesive layer 16 in the entire area of ​​the main surface 12B of the cover glass 12 becomes the adhesive area AR. The adhesive area AR may be discontinuous, or a plurality of discontinuous or patchy adhesive areas AR may be formed.

[0103] (Length of the bent portion L)

[0104] The length (circumference) L of the curved portion 20 refers to the length of the curved portion 20 along the main surface in the X direction orthogonal to the bending axis. The length L refers to the length of a line connecting an end point (position) on one side of the curved portion 20 in the X direction with an end point (position) on the other side of the curved portion 20 in the X direction and extending in the X direction on the main surface 12B. The line extending in the X direction on the main surface 12B refers to a line extending in the X direction along the main surface 12B without deviating in the Y direction. Figure 3A In the example, the endpoint of one side of the bend 20 in the X direction is a point on the side 12C1, and the endpoint of the other side of the bend 20 in the X direction is a point on the side 12C2, so the length L refers to the length of the line from the side 12C1 to the side 12C2 on the main surface 12B toward the X direction.

[0105] The length L is preferably 100 mm or more and 2000 mm or less, more preferably 150 mm or more and 700 mm or less, and further preferably 200 mm or more and 400 mm or less. By setting the length L preferably to 2000 mm or less, more preferably to 700 mm or less, and further preferably to 400 mm or less, W can be increased and the parameter A can be reduced, so that the deviation of the cover glass 12 from the desired curved shape can be appropriately suppressed. In addition, by setting the length L preferably to 100 mm or more, more preferably to 150 mm or more, and further preferably to 200 mm or more, the deterioration of the design can be suppressed.

[0106] In this embodiment, even if the region has the same radius of curvature R, the region with a length L of 5 mm or less (such as surface irregularities and fine undulations) is not treated as the curved portion 20. That is, the region with the same radius of curvature R and a length L longer than 5 mm is treated as the curved portion 20.

[0107] (Value W)

[0108] The area B (cm 2 ) divided by the length L (cm) of the curved portion 20 is preferably 1 cm to 20 cm, more preferably 2 cm to 6.2 cm. By making the value W within this range, it is possible to suppress the deterioration of the design and appropriately suppress the deviation of the cover glass 12 from the desired curved shape.

[0109] (Method for manufacturing glass article)

[0110] Next, a method for producing the glass article 10 will be described. Figure 5 Schematic diagram for explaining the manufacturing method of the glass article and the display device involved in this embodiment. Figure 5As shown, in the manufacturing method of the present embodiment, the cover glass 12 including the curved portion 20 is formed by heating the flat cover glass 12, i.e., the glass plate, while bending it (by performing heat forming). The cover glass 12 in the stage of step S10, i.e., the cover glass 12 in the state not mounted on the frame 14, is bent in a manner to have the above-mentioned radius of curvature R1. Next, the main surface 12B of the cover glass 12 is bonded to the frame 14 via the adhesive layer 16 to form the glass article 10 (step S12). The cover glass 12 after step S12, i.e., the cover glass 12 in the state mounted on the frame 14, is bent in a manner to have the above-mentioned radius of curvature R. Then, the display 3 is mounted on the main surface 12B of the glass article 10 at a position inside the bonding area AR to which the frame 14 and the adhesive layer 16 are bonded (step S14). Then, the glass article 10 with the display 3 mounted thereon is mounted on the housing 4 to form the display device 2 (step S16). In step S16 , the glass article 10 with the display 3 mounted thereon is mounted on the housing 4 so that the display 3 is accommodated in the housing 4 and the main surface 12A side is exposed to the outside.

[0111] In addition, although Figure 5 In the example, the main surface 12B on which the frame 14 and the display 3 are mounted is convex, and the main surface 12A exposed to the outside is concave, but it is not limited to this, and it can also be as follows Figure 2 As shown in FIG. 1 , the main surface 12B is concave, and the main surface 12A is convex. In addition, the step of accommodating in the housing 4 as in step S16 is not essential, and the glass article 10 with the display 3 mounted thereon may be handled as the display device 2 .

[0112] In the present manufacturing method, after step S10, the cover glass 12 is preferably chemically strengthened. More specifically, after step S10, the heat-formed cover glass 12 is preferably chemically strengthened, and thereafter step S12 is performed to attach the frame 14 to the chemically strengthened cover glass 12.

[0113] (Effect)

[0114] As described above, the glass article 10 involved in the first form of the present embodiment includes: a cover glass 12 that is heat-formed and includes a curved portion 20; a frame 14 that is provided on the main surface 12B of the cover glass 12; and an adhesive layer 16 that is provided between the main surface 12B of the cover glass 12 and the frame 14 to bond the cover glass 12 to the frame 14. The parameter A of the glass article 10 is greater than 0 and is less than 0.5. The glass article 10 involved in the present embodiment can bend the cover glass 12 appropriately into a desired shape by bonding the cover glass 12 that has been bent to a certain extent by heat forming to the frame 14. In addition, the parameter A is less than 0.5, so that, for example, the value PV described later can be suppressed to a deviation of less than 0.5, so that the deviation of the cover glass 12 from the desired curved shape can be appropriately suppressed.

[0115] In the glass article 10 according to the second aspect of the present embodiment, it is preferable that, in the glass article 10 according to the first aspect, the absolute value of the difference between the radius of curvature R1 of the curved portion of the cover glass 12 in a state where the cover glass 12 is removed from the frame 14 and the radius of curvature R of the curved portion of the cover glass 12 in a state where the cover glass 12 is attached to the frame 14 is 10% or less of the radius of curvature R. By setting the absolute value of the difference in the radius of curvature to be within this range, it is possible to suppress the deviation of the cover glass 12 in the glass article from a desired shape.

[0116] The glass article 10 according to the third aspect of the present embodiment is preferably the glass article 10 according to the first aspect or the second aspect, wherein the radius of curvature R of the curved portion 20 of the cover glass 12 is greater than or equal to 100 mm and less than or equal to 8000 mm. By setting the radius of curvature R within this range, the design property can be improved and the deviation between the cover glass 12 and the desired shape can be suppressed.

[0117] The glass article 10 according to the fourth aspect of the present embodiment is preferably the glass article 10 according to any one of the first to third aspects, wherein the thickness t1 of the cover glass 12 is greater than 1 mm. By setting the thickness t1 within this range, the deviation of the cover glass 12 from a desired shape can be suppressed.

[0118] The glass article 10 according to the fifth aspect of the present embodiment is preferably the glass article 10 according to any one of the first to fourth aspects, wherein the radius of curvature R1 of the curved portion of the cover glass 12 in a state where the cover glass 12 is removed from the frame 14 is 50 mm or more and 10000 mm or less. By setting the radius of curvature R1 within this range, the design property can be improved, and the deviation between the cover glass 12 and the desired shape can be appropriately suppressed.

[0119] The glass article 10 according to the sixth aspect of the present embodiment is preferably the glass article 10 according to any one of the first to fifth aspects, wherein the Young's modulus E1 of the cover glass 12 is 60 GPa or more and 90 GPa or less, the Young's modulus E2 of the frame 14 is 1 GPa or more and 400 GPa or less, the elastic modulus E3 of the adhesive layer 16 is 0.2 MPa or more and 100 MPa or less, and the cross-sectional inertia moment I2 of the frame 14 is 0.1 mm or more. 4 Above and 1250mm 4 By setting these parameters to be in the above ranges, it is possible to appropriately suppress the deviation of the cover glass 12 from a desired shape.

[0120] The glass article 10 according to the seventh aspect of the present embodiment is preferably the glass article 10 according to any one of the first to sixth aspects, wherein the cover glass 12 is chemically strengthened. By chemically strengthening, strength can be improved.

[0121] The display device 2 according to the eighth aspect of the present embodiment includes a display 3 and the glass article 10 according to any one of the first to seventh aspects provided on the surface of the display 3. Therefore, deviation of the cover glass 12 from a desired shape can be appropriately suppressed.

[0122] The manufacturing method of the glass article according to the ninth aspect of the present embodiment includes: a step of bending a glass plate while heating it to thereby form a cover glass 12 including a bent portion 20; and a step of bonding the main surface 12B of the cover glass 12 to the frame 14 via the adhesive layer 16 to thereby manufacture the glass article 10. According to the present manufacturing method, it is possible to appropriately suppress the deviation of the cover glass 12 from a desired shape.

[0123] The manufacturing method of the glass article according to the tenth aspect of the present embodiment is preferably a method for manufacturing a glass article according to the ninth aspect, wherein the cover glass 12, the frame 14, and the adhesive layer 16 are used, wherein the parameter A defined by the formula (1) is 0.5 or less. According to the present manufacturing method, by setting the parameter A to 0.5 or less, for example, the value PV described later can be suppressed to a deviation of 0.5 or less, and thus the deviation of the cover glass 12 from the desired curved shape can be appropriately suppressed.

[0124] The manufacturing method of the glass article according to the 11th aspect of the present embodiment is preferably the manufacturing method of the glass article according to the 9th aspect or the 10th aspect, further comprising a step of chemically strengthening the cover glass 12 after the step of forming the cover glass 12. According to this manufacturing method, the strength of the cover glass 12 can be improved and breakage can be suppressed.

[0125] The manufacturing method of the display device according to the twelfth aspect of the present disclosure includes the step of attaching the glass article 10 manufactured by the manufacturing method according to any one of the ninth to eleventh aspects to the display 3 to manufacture the display device 2. According to this manufacturing method, the deviation between the cover glass 12 and the desired shape can be appropriately suppressed.

[0126] (Another example)

[0127] Next, another example of the glass article 10 according to the present embodiment will be described.

[0128] (Example of multiple adhesive layers)

[0129] Figure 6 1 is a diagram showing an example of providing a plurality of adhesive layers. Although in the above description, one adhesive layer 16 is provided, a plurality of adhesive layers 16 may also be provided. In this case, Figure 6 As shown, each adhesive layer 16 is bonded to the main surface 12B of the cover glass 12 at different positions when viewed from the Z direction. When multiple adhesive layers 16 are provided, it is preferred to provide an adhesive layer 16 having a lower adhesive force (elastic modulus) than the adhesive layer 16 having a higher adhesive force (elastic modulus) at a radially outer position. For example, by providing an adhesive layer 16 having a lower adhesive force such as a double-sided tape on the outside, it functions as a dam for the adhesive layer 16 (e.g., adhesive) on the inside having a higher adhesive force, and thus it is possible to suppress the adhesive from overflowing to the outside before curing. Figure 6 In the example of , each adhesive layer 16 is provided in a state where the outer periphery of the inner adhesive layer 16 is separated from the inner periphery of the outer adhesive layer 16. However, Figure 6 is an example, and the position of each adhesive layer 16 can be set arbitrarily. Figure 6 Although two adhesive layers 16 are provided as an example, three or more adhesive layers 16 may be provided.

[0130] (Example of spline shape)

[0131] Figure 7is a schematic diagram of a cover glass involved in another example of the present embodiment. In the above-mentioned embodiment, the curved portion 20 is described as a portion curved with the same radius of curvature R, but there is also a case where it is curved in the X direction in the shape of a spline curve with a non-constant radius of curvature. In this case, the entire portion curved in the X direction in the shape of a spline curve is treated as the curved portion 20. In the description of the above-mentioned embodiment, an area on the main surface 12B that is curved with the Y direction as the bending axis, in which the change in the radius of curvature R measured at each position from the end point on one side in the X direction to the end point on the other side is less than 5%, is treated as a curved portion 20 with the same radius of curvature. On the other hand, in this example, an area on the main surface 12B that is curved with the Y direction as the bending axis, in which the change in the radius of curvature R at each position in an interval of less than 50 mm in length from the end point on one side in the X direction toward the end point on the other side is treated as a spline-shaped curved portion 20. Moreover, as Figure 7 As shown, the spline-shaped curved portion 20 is approximated to a shape curved with a constant radius of curvature, and the curvature radius when approximated to a shape curved with a constant radius of curvature is handled as the curvature radius R of the curved portion 20 .

[0132] Specifically, one end point of the main surface 12B of the spline-shaped curved portion 20 in the X direction is defined as an end point 20J, and the other end point is defined as an end point 20K, and a plane connecting the end points 20J and 20K and along the X direction and the Y direction (i.e., an XY plane passing through the end points 20J and 20K) is defined as a plane α. Furthermore, when a plane β is defined as a plane obtained by translating the plane α in the Z direction so as to be tangent to the main surface 12B, the curvature radius of the arc 20R passing through the end points 20J and 20K and being tangent to the plane β is defined as the curvature radius R of the curved portion 20.

[0133] (Example with flat portion)

[0134] Figure 8 as well as Fig. 9 : is a schematic diagram of the cover glass involved in another example of the present embodiment. The flat portion 22 may also be connected to the X1 side of the curved portion 20. The direction X1 refers to the direction along one side of the X direction, and the direction X2 refers to the direction along the other side of the X direction. The flat portion 22 is connected to the curved portion 20 in a manner that the main surface 12B is continuous with the curved portion 20 (in a manner that is not discontinuous). The flat portion 22 is a flat portion in the entire area of ​​the cover glass 12 that is connected to the end of the curved portion 20 on the X1 side. The flatness of the flat portion 22 means that it is not limited to an infinite radius of curvature, but may also include a radius of curvature greater than 10000 mm.

[0135] When the curved portion 20 is connected to the flat portion 22, the curved portion 20 and the flat portion 22 are treated as one curved portion 20a for the application of equations (1) and (2). Figure 8 In this case, when the flat portion 22 is provided on the X1 side of the curved portion 20 and the flat portion 22 is not provided on the X2 side, the length of the curved portion 20a in the X direction (the sum of the length of the curved portion 20 in the X direction and the length F of the flat portion 22) is treated as the length L. In addition, the area of ​​the region overlapping with the adhesive layer 16 on the main surface 12B of the curved portion 20a (the sum of the area of ​​the region overlapping with the adhesive layer 16 on the main surface 12B of the curved portion 20 and the area of ​​the region overlapping with the adhesive layer 16 on the main surface 12B of the flat portion 22) is treated as the area B.

[0136] Here, the length F of the flat portion 22 refers to the length of the flat portion 22 along the main surface 12B from the end point of the main surface 12B on the X1 side to the end point of the main surface 12B on the X2 side.

[0137] like Fig. 9 As shown in FIG. 1 , the flat portion 22 may be connected to both sides of the curved portion 20 in the X direction (the side facing X1 and the side facing X2). Fig. 9 As shown, when the length F along the main surface 12B of the flat portion 22 facing the X1 side and the flat portion 22 facing the X2 side of the curved portion 20 is different, the curved portion 20 and the flat portion 22 having the shorter length F along the main surface 12B are treated as one curved portion 20a. That is, the length in the X direction of the curved portion 20a (the total value of the length of the curved portion 20 and the length F of the shorter flat portion 22) is treated as the length L, and the area of ​​the region overlapping with the adhesive layer 16 on the main surface 12B of the curved portion 20a (the total value of the area of ​​the region overlapping with the adhesive layer 16 on the main surface 12B of the curved portion 20 and the area of ​​the region overlapping with the adhesive layer 16 on the main surface 12B of the shorter flat portion 22) is treated as the area B. When the flat portion 22 of the curved portion 20 facing the X1 side and the flat portion 22 facing the X2 side have the same length F along the principal surface 12B, the curved portion 20 and either flat portion 22 are treated as one curved portion 20 a .

[0138] (Example of multiple cases of curved parts)

[0139] Fig.10 as well as Fig.11 2 is a schematic diagram of a cover glass according to another example of the present embodiment. A plurality of curved portions 20 may be provided, in other words, a plurality of curved portions 20 having different curvature radii R may be formed on the cover glass 12. In this case, each curved portion 20 is curved with the same direction, that is, the Y direction, as the bending axis.

[0140] The number of the bent portions 20 can be determined as follows. That is, in a region where the change in the radius of curvature R at each position in a section longer than 50 mm from the end point on one side in the X direction toward the end point on the other side of the region bent with the Y direction as the bending axis is higher than 5%, it is determined that a plurality of bent portions 20 having different radiuses of curvature R are formed. That is, although the change in the radius of curvature R in a section shorter than 50 mm from the end point on one side in the X direction toward the end point on the other side of the region bent with the Y direction as the bending axis on the main surface 12B is 5% or less, if the change in the radius of curvature R in a section longer than 50 mm from the end point on one side toward the end point on the other side exceeds 5%, it is determined that a plurality of bent portions are formed rather than a single spline-shaped bent portion.

[0141] In this case, if Fig.10 As shown in the example, in the area on the main surface 12B that is bent with the Y direction as the bending axis, an area in which the change in the radius of curvature R at each position in the interval from the end point 20L on one side of the area in the X direction toward the end point 20M on the other side is less than 5% is set as a curved portion 20A with the same radius of curvature R. The curved portion 20A is an area from the end point 20L on one side to the position 20N where the change in the radius of curvature R becomes greater than 5%. Furthermore, an area in which the change in the radius of curvature R at each position in the interval from the position 20N toward the end point 20M on the other side is less than 5% is set as another curved portion 20B. Fig.10 In the example of FIG. 2, since the change in the curvature radius R in the section from the position 20N to the end point 20M is less than 5%, the region from the position 20N to the end point 20M is treated as the curved portion 20B. However, if, for example, there is a position from the position 20N to the end point 20M where the change in the curvature radius R becomes greater than 5%, the region from the position 20N to the position where the change in the curvature radius R becomes greater than 5% is one curved portion 20B. In this case, there are three or more curved portions 20.

[0142] When a plurality of bent portions 20 are formed in this manner, equations (1) and (2) are applied to each of the bent portions 20 . Fig.10 An example is shown in which a curved portion 20A having a curvature radius Ra and a curved portion 20B having a curvature radius Rb are formed. Fig.10 In the example of , both the curved portions 20A and 20B are convex toward the main surface 12A side, but the present invention is not limited thereto, and both the curved portions 20A and 20B may be convex toward the main surface 12B side. That is, when there are a plurality of curved portions 20, each curved portion 20 may be convex toward the same direction. In addition, the number of curved portions 20 is not limited to two, and may be three or more.

[0143] Fig.11 This is an example of a case where a plurality of curved portions 20 are connected to a flat portion 22. When a plurality of curved portions 20 are connected to a flat portion 22, when equations (1) and (2) are applied, one curved portion 20 and the flat portion 22 connected to the curved portion 20 are treated as one curved portion 20a. Fig.11 In the example of , the long flat portion 22 is connected to the X2 side of the curved portion 20B, the short flat portion 22 is connected to the X1 side of the curved portion 20B, and the curved portion 20A is connected to the side of the short flat portion 22 opposite to the curved portion 20B. In this case, the curved portion 20A and the short flat portion 22 are treated as one curved portion 20a, and the curved portion 20B and the short flat portion 22 are treated as another curved portion 20a. The calculation method of the length L and the area B of the curved portion 20a is the same as the case where the flat portion 22 is connected to one curved portion 20, so the description is omitted.

[0144] Figures 12 to 15 Schematic diagram of a cover glass according to another example of the present embodiment. In the above description of the embodiment, a rectangular glass plate is bent in the X direction to form the cover glass 12, so the length of the cover glass 12 in the X direction is constant at each position, but sometimes the length of the cover glass 12 in the X direction is different at each position depending on the shape. The length L in such a case is described below.

[0145] As described above, the length L is the length of a line extending in the X direction on the principal surface 12B, connecting the position of the bent portion 20 closest to one side (toward the X1 side) in the X direction with respect to the bending axis YA along the direction Y and the position of the bent portion 20 closest to the other side (toward the X2 side) in the X direction with respect to the bending axis YA. Fig.12 In that case, when a trapezoidal glass plate is bent with the Y direction as the bending axis to form a cover glass 12, the two end points of the long side of the trapezoid, i.e., the side surface 12C3, become the position 20C closest to the X2 side and the position 20D closest to the X1 side of the bent portion 20 relative to the bending axis YA, and the length of the line connecting the position 20C and the position 20D and facing the X direction on the main surface 12B is the length L.

[0146] In addition, although in the above description, the X direction orthogonal to the bending axis is along the lateral edges of the flat cover glass 12 before bending, namely the side surfaces 12C3 and 12C4, the present invention is not limited to this. The X direction orthogonal to the bending axis can also be offset relative to (or cross) the edges of the flat cover glass 12 before bending. Fig.13 An example is shown in which the X direction intersects the side surfaces 12C3 and 12C4 of the flat cover glass 12 before bending. Fig.13In the example, the endpoint of one side 12C3, which is the long side of the trapezoid, is at position 20C, and the endpoint of the other side 12C4, which is the short side of the trapezoid, is at position 20D. Fig.13 In the example, since the positions 20C and 20D in the Y direction are not aligned, the length of the line connecting the position 20D′ and the position 20C which are offset in the Y direction and extending in the X direction along the main surface 12B is set to length L. Fig.13 In the example of FIG. 1 , the length of the curve connecting the position 20C and the position 20D′ and having a curvature radius R is the length L. The position 20D′ is a position obtained by shifting the position 20D in the Y direction so that the position in the Y direction is aligned with the position in the Y direction of the position 20C. In this way, when the positions in the Y direction of the position 20C and the position 20D are not aligned, the length of the line extending in the X direction along the surface of the main surface 12B from the position 20C to the position 20D′, which are aligned in the Y direction, is set to the length L.

[0147] Fig.14 This is an example of a case where a polygonal glass plate is bent in the X direction to form the cover glass 12. Fig.14 In the example, since the Y-direction positions of the points of the bent portion 20 that are closest to the X2 side and the X1 side in the X direction relative to the bending axis YA along the direction Y, namely, positions 20C and 20D, are not aligned, the length of a line connecting position 20D' and position 20C and facing the X direction along the main surface 12B is set to length L.

[0148] Fig.15 This is an example of a case where a glass plate having a curved outer periphery is bent in the X direction to form the cover glass 12. Fig.15 In the example, since the Y-direction positions of the points of the bent portion 20 that are closest to the X2 side and the X1 side in the X direction relative to the bending axis YA along the direction Y, namely, positions 20C and 20D, are not aligned, the length of a line connecting position 20D' and position 20C and facing the X direction on the surface along the main surface 12B is set to length L.

[0149] Figures 16 to 18 1 is a schematic diagram of a cover glass according to another example of the present embodiment. In the above description, the plurality of curved portions 20 are curved in the same direction with the Y direction as the bending axis, but the directions of the bending axes of the plurality of curved portions 20 may be different. In this case, the bending axes of the respective curved portions 20 do not intersect on the main surface 12A of the cover glass 12, but intersect at a point where the bending axes of the respective curved portions 20 are extended toward the outside of the main surface 12A.

[0150] Fig.16as well as Fig.17 An example of a schematic diagram of a cover glass 12 in which the directions of the bending axes of the plurality of bent portions 20 are different is shown. Fig.16 In the example, the curved portion 20A is connected to the X2 side of the flat portion 22, and the curved portion 20B is connected to the X1 side of the flat portion 22. The curved portion 20A is bent with the bending axis YA as the bending axis from the end side facing the X2 side, that is, the side surface 12C1, to the end side facing the X1 side 20P. That is, the curved portion 20A is a region bent with the bending axis YA as the bending axis in such a manner that the change in the curvature radius at each position in the X direction from the side surface 12C1 to the end side 20P is 5% or less. The curved portion 20B is bent with the bending axis YB as the bending axis from the end side 20Q facing the X2 side to the side surface 12C2, that is, the end side facing the X1 side. That is, the curved portion 20B is a region bent with the bending axis YB as the bending axis in such a manner that the change in the curvature radius at each position in the X direction from the end side 20Q to the side surface 12C2 is 5% or less. The flat portion 22 is a flat region extending from the end side 20P to the end side 20Q in the X direction.

[0151] Although the bending axis YA of the curved portion 20A and the bending axis YB of the curved portion 20B extend in different directions, they do not intersect on the main surface 12A of the cover glass 12, but intersect at a point where the bending axes YA and YB are extended to the outside of the main surface 12A. Fig.16 For convenience of explanation, the figure shows the Y direction as the bending axis, that is, the bending axes YA and YB are in the same direction, but in fact, the bending axes YA and YB of the bending portions 20A and 20B extend in different directions.

[0152] When a plurality of curved portions 20 having different bending axis directions are connected to a flat portion 22, when equations (1) and (2) are applied, one curved portion 20 and the flat portion 22 connected to the curved portion 20 are treated as one curved portion 20a. Fig.17 In the example of FIG. 1 , the flat portion 22 is connected to the curved portion 20A on the X1 side, and the flat portion 22 is connected to the curved portion 20B on the X2 side. In this case, the curved portion 20A and the flat portion 22 are treated as one curved portion 20a, and the curved portion 20B and the flat portion 22 are treated as another curved portion 20a. The calculation method of the area B of the curved portion 20a is the same as the case where the flat portion 22 is connected to one curved portion 20, so the description is omitted.

[0153] based on Fig.18 , a method for calculating the length L in a plurality of bent portions 20 having different bending axis directions will be described. Fig.18 For the sake of convenience of explanation, the curved portion 20a including the curved portion 20A and the flat portion 22 is extracted. Fig.18 In the example of FIG. 20 , the end point of the side surface 12C1 closest to the X2 side is the position 20C of the curved portion 20a, and the end point of the end side 20P closest to the X1 side is the position 20D of the curved portion 20a. In the example of FIG. 20 , since the positions of the positions 20C and 20D in the Y direction are not aligned, the length of the line connecting the position 20D' obtained by shifting the position 20D in the Y direction and the position 20C and facing the X direction along the main surface 12B is set as the length L of the curved portion 20a. That is, in the example of FIG. 20 , the length of the curve connecting the position 20C and the position 20D' and having a curvature radius of R is the length L. In addition, the length L is also obtained in the same manner for the curved portion 20a including the curved portion 20B and the flat portion 22, but the description is omitted.

[0154] Example

[0155] Next, examples will be described. In addition, the embodiments may be changed as long as the effects of the invention are exerted. In each example, a test based on simulation was performed.

[0156] (simulation)

[0157] For the simulation, impact collision analysis software using the finite element method (PAM-CRASH manufactured by ESI Co., Ltd., Japan) was used. In the simulation, COS3D (Material Type 305) that can set the bonding fracture energy was used as the bonding layer, and the bonding fracture energy EFRSn was set in a manner integrated with the actual test. In the simulation, first, the glass plate is given elastic energy of bending (stored as stress of the glass). At this time, the glass plate with an initial shape that simulates the bending amount caused by actual thermal bending is elastically corrected to an ideal shape. In this way, the elastic energy equivalent to the bending amount can be stored as stress of the glass. Next, the frame is attached to the glass plate storing the elastic energy via the bonding layer. Due to the elastic energy of the glass, the glass, the bonding layer and the frame are deformed and balanced in a specified state. The maximum value of the deviation of the distance in the vertical direction between the shape in the specified state of equilibrium at this time and the ideal shape is calculated as the value PV. Among them, the initial shape in the simulation can be set based on the desired elastic energy to be given to the glass plate, and the desired elastic energy is the same value in each example.

[0158] In addition, since the elements whose bonding energy exceeds the bonding breaking energy in the bonding layer disappear, the phenomenon of glass peeling off from the frame can be simulated. However, it was confirmed that there was no deviation between the simulation results and the actual test results.

[0159] (Simulation conditions)

[0160] Table 1 shows the conditions of the simulation model of each example. For example, in Example 1, the model is prepared by bonding the cover glass and the frame using one adhesive layer (first adhesive layer) in such a way that the radius of curvature R of the cover glass becomes the value described in Table 1. Similarly, in Examples 16 and 17, two adhesive layers (first adhesive layer and second adhesive layer) are used as adhesive layers for bonding the cover glass and the frame. The thickness t1 of the cover glass, the Young's modulus E1, the moment of inertia I2 of the frame, the Young's modulus E2, the elastic modulus E3 of the first adhesive layer, the elastic modulus E3 of the second adhesive layer, and the value W are set to the values ​​shown in Table 1.

[0161] In addition, the parameter A was calculated for each example. Table 1 shows the value of the parameter A.

[0162] [Table 1]

[0163]

[0164] (evaluate)

[0165] In the evaluation, the value PV, which is the amount of deviation between the cover glass and the desired shape in the simulation, is calculated. The value PV is calculated as described above.

[0166] In the evaluation, the case where the value PV is 0.5 or less is qualified, and the case where the value PV is higher than 0.5 is unqualified. In Examples 1 to 3 and 5 to 18, which are examples and in which the parameter A is 0.5 or less, it is known that the value PV is qualified and the deviation between the cover glass and the desired shape can be suppressed. On the other hand, in Examples 4 and 19, which are comparative examples and in which the parameter A is higher than 0.5, it is known that the value PV is unqualified and the deviation between the cover glass and the desired shape cannot be suppressed.

[0167] Although the embodiments of the present invention have been described above, the embodiments are not limited by the contents of the embodiments. In addition, the above-mentioned constituent elements include constituent elements that are easily thought of by those skilled in the art, substantially the same constituent elements, and constituent elements within the so-called equal range. Furthermore, the above-mentioned constituent elements can be appropriately combined. Furthermore, various omissions, substitutions or changes of constituent elements can be performed within the scope of the gist of the above-mentioned embodiments.

[0168] Industrial Applicability

[0169] According to the present invention, it is possible to suppress deviation of the cover glass from a desired shape.

[0170] While the present invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the present invention.

[0171] This application is based on the Japanese patent application (Japanese Patent Application No. 2022-123808) filed on August 3, 2022, and the contents are incorporated herein by reference.

[0172] Description of Reference Numerals

[0173] 1...steering shaft; 2...display device; 3...display; 4...housing; 10...glass article; 12...cover glass; 12A, 12B...main surface; 12C1, 12C2, 12C3, 12C4...side surface; 14...frame; 16...adhesive layer; 20, 20A, 20B...bend portion; 20a...bend portion; 20C, 20D, 20D', 20N...position; 20J, 20K, 20L, 20M...end point; 20P, 20Q...end edge; 20R...arc; 22...flat portion.

Claims

1. A glass article, wherein: The glass article has: a cover glass that is heat-formed and includes a curved portion; A frame, arranged on a main surface of the cover glass; as well as an adhesive layer, disposed between the main surface of the cover glass and the frame, so as to bond the cover glass to the frame; The parameter A defined by the following formula (1) is greater than 0 and less than 0.5, here, E1 is the Young's modulus of the cover glass, in GPa, t1 is the thickness of the cover glass, in mm, E2 is the Young's modulus of the frame in GPa, I2 is the section moment of inertia of the frame, in mm 4 , E3 is the elastic modulus of the adhesive layer, in MPa, W is the value obtained by dividing the area of ​​the adhesive layer by the length of the bent portion along the main surface in a direction perpendicular to the bending axis, and the unit of the area of ​​the adhesive layer is cm. 2 , the unit of the length is cm.

2. The glass article according to claim 1, wherein An absolute value of a difference between a curvature radius R1 of the curved portion of the cover glass when the cover glass is removed from the frame and a curvature radius R of the curved portion of the cover glass when the cover glass is attached to the frame is 10% or less of the curvature radius R.

3. The glass article according to claim 1 or 2, wherein: A curvature radius R of the curved portion of the cover glass is greater than or equal to 100 mm and less than or equal to 8000 mm.

4. The glass article according to claim 1 or 2, wherein: The thickness t1 of the cover glass is greater than 1 mm.

5. The glass article according to claim 1 or 2, wherein: A curvature radius R1 of the curved portion of the cover glass in a state where the cover glass is removed from the frame is greater than or equal to 50 mm and less than or equal to 10000 mm.

6. The glass article according to claim 1 or 2, wherein: The Young's modulus E1 of the cover glass is greater than or equal to 60 GPa and less than or equal to 90 GPa. The Young's modulus E2 of the frame is greater than or equal to 1 GPa and less than or equal to 400 GPa, The elastic modulus E3 of the adhesive layer is greater than or equal to 0.2 MPa and less than or equal to 100 MPa. The frame's section moment of inertia I2 is 0.1 mm 4 Above and 1250mm 4 the following.

7. The glass article according to claim 1 or 2, wherein: The cover glass is chemically strengthened.

8. A display device, wherein: A glass article according to claim 1 or 2, comprising a display and a surface provided on the display.

9. A method for manufacturing a glass article, in, include: A step of bending a glass sheet while heating it to form a cover glass including a bent portion; and A step of bonding the main surface of the cover glass to a frame via an adhesive layer to produce a glass article.

10. The method for manufacturing a glass article according to claim 9, wherein: The cover glass, the frame, and the adhesive layer are used, wherein the parameter A defined by the following formula (1) is 0.5 or less. here, E1 is the Young's modulus of the cover glass, in GPa, t1 is the thickness of the cover glass, in mm, E2 is the Young's modulus of the frame in GPa, I2 is the section moment of inertia of the frame, in mm 4 , E3 is the elastic modulus of the adhesive layer, in MPa, W is the value obtained by dividing the area of ​​the adhesive layer by the length of the bent portion along the main surface in a direction perpendicular to the bending axis, and the unit of the area of ​​the adhesive layer is cm. 2 , the unit of the length is cm.

11. The method for manufacturing a glass article according to claim 9 or 10, wherein: The method further includes a step of chemically strengthening the cover glass after the step of forming the cover glass.

12. A method for manufacturing a display device, wherein: The method comprises the step of attaching the glass article manufactured by the method for manufacturing a glass article according to claim 9 or 10 to a display to manufacture a display device.

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