Composite and manufacturing method thereof, and display device

Abstract

To fix a joint member stably without causing a sink and a warpage to a front side of a display panel on integrally providing a joint member bonded to a housing on a back side of a thin glass display panel.SOLUTION: A resin molding 5 made from a resin material including a thermoplastic elastomer is arranged to a bonding portion of a joint member 3, 4 fixing to a back side of a glass substrate 2, a seat part 31, 41 of the joint member 3, 4 is surface-covered and integrally molded with this resin molding 5. By arranging the resin molding 5 at the bonding portion, a compressive force of a resin on molding is made small, thus formation of a sink and a warpage on a front side of a glass substrate 2 is suppressed.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a glass composite used in a display panel of a display device for displaying information and images, such as a car navigation system. [Background technology]

[0002] Display panels for display devices that show various types of information and images are made of synthetic resin or glass, but glass panels are often used in high-end devices because the glossy texture of the panel creates a sense of luxury. The display panel is attached to the front frame of the housing that houses the electronic device, and in many cases, the back side of the glass display panel is attached to the front frame using adhesive tape or the like. However, fixing by adhesive is a complicated process that requires the preparation of the adhesive tape required for fixing and adjustments to accurately position the fixing position. Furthermore, if the display panel becomes scratched or broken and needs to be replaced, it is difficult to do so because it is fixed with adhesive tape or the like.

[0003] Therefore, instead of the above-mentioned fixing method by adhesion, a method is being considered in which a joining portion such as a rib made of a resin material is integrally attached to the back side of a glass display panel by outsert molding, and the joining portion is joined to a joining portion provided on the front frame portion of the housing, thereby attaching the display panel to the housing (see, for example, Patent Document 1). Another known method for integrally attaching the joining member to a glass display panel is to bond a resin joining member to the glass surface via a thermoplastic elastomer layer by two-color molding (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-159114 [Patent Document 2] Japanese Patent Application Publication No. 2023-39774 Summary of the Invention [Problem to be solved by the invention]

[0005] When forming a bonding portion on the back side of a glass display panel using outsert molding, if the bonding portion is thick and wide, there is a problem that the difference in thermal contraction between the glass and the resin causes the bonding portion to be insufficiently fixed to the back side of the display panel, making the bonding portion prone to peeling off.

[0006] Furthermore, for example, in the case of a display panel for a car navigation system, from the viewpoint of design, it is desirable to fix the display panel formed from a curved thin glass substrate to a housing. However, in an embodiment in which a bonding portion is provided on the back side of a thin glass substrate that can be bent by outsert molding, heat shrinkage of the resin used in the bonding portion is likely to cause sink marks or undulations on the front side of the glass substrate, which can degrade the quality of the appearance of the display panel.

[0007] In this case, as will be described later, it is presumed that the occurrence of sink marks and undulations can be suppressed by using a resin material with properties that result in little shrinkage force during molding, such as a soft, elastic polymeric material such as an elastomer. However, because the joining parts molded from elastomer are soft, there is a problem in that it is difficult to adopt a method of fixing the display panel to the housing by using fastening screws to fasten the joining part to the joined part.

[0008] Furthermore, although the mode of joining the connecting member to the glass surface via a thermoplastic elastomer layer by two-color molding can suppress the occurrence of sink marks and undulations on the front side of the glass, two-color molding has the problem that the resin containing the thermoplastic elastomer can only flow between the connecting member and the glass surface, which inevitably weakens the fixation of the connecting member to the glass surface.

[0009] In view of the problems associated with conventional technology, the present invention aims to provide a method for stably fixing and securing a joining member to the rear side of a thin glass display panel, which serves as a joining site for fixing the panel to a housing, without causing sink marks or undulations to appear on the front side of the display panel. [Means for solving the problem]

[0010] In order to solve the above problems, the glass composite of the present invention includes the following aspects. [1] A composite in which a bonding member is provided on the surface of a glass substrate, The joining member has a seat portion, and the lower and upper surfaces of the seat portion are covered and fixed with a resin molded body containing a thermoplastic elastomer bonded to the surface of a glass substrate. [2] The composite according to [1], characterized in that it has a hole penetrating the seat in the thickness direction, and the resin molding is also contained in the hole. [3] The composite according to [1] or [2], wherein the resin molded body is a polyester-based thermoplastic elastomer. [4] The composite according to any one of [1] to [3], wherein the resin molded body has a tensile modulus of elasticity of 100 MPa or less. [5] The composite according to any one of [1] to [4], wherein the material of the joining member is a synthetic resin or a metal. [6] The composite according to [5], wherein the synthetic resin material of the joining member is mainly composed of at least one of ABS resin, polycarbonate resin, and polybutylene terephthalate resin. [7] The composite according to any one of [1] to [6], wherein a printed layer and an adhesive layer are laminated on a part of the surface of the glass substrate, and a resin molded body is disposed on the surface of the adhesive layer. [8] The composite according to any one of [1] to [7], wherein the thickness of the glass substrate is 0.2 to 2.0 mm. [9] A method for producing the complex according to any one of [1] to [8], Inserting a glass substrate and a bonding member into a molding die; a step of closing the molding die and injecting a resin molding into the space between the glass substrate and the joining member and on the upper surface of the seat portion of the joining member; a step of opening the molding die and removing a composite in which the bonding member is fixed to the surface of the glass substrate; A method for producing a composite, comprising:

[10] A display device using the composite according to any one of [1] to [8] as a display panel. [Effects of the Invention]

[0011] According to the composite of the present invention, even when a joining member, which is a connecting portion for fixing the display panel to a housing, is integrally provided on the rear side of a thin glass display panel via a resin molded body, the joining member can be stably and firmly fixed to the rear side of the display panel without causing sink marks or undulations to appear on the front side of the display panel. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing the front and rear surfaces of a display panel, which is an embodiment of the composite of the present invention, divided into two parts. [Figure 2] 2 is an enlarged cutaway perspective view of a portion of the display panel in FIG. 1 where a bonding member is provided on the upper side. [Figure 3] 2 is an external view of a bonding member on the upper side of the display panel in FIG. 1. FIG. [Figure 4] 2 is an enlarged cross-sectional view of a portion of the display panel shown in FIG. 1 where a bonding member is provided on the upper side. [Figure 5] 2 is an external view of a joint member on the lower side of the display panel in FIG. 1. FIG. [Figure 6] 2 is an enlarged cross-sectional view of a portion of the display panel shown in FIG. 1 where a joining member is provided on the lower side thereof. DETAILED DESCRIPTION OF THE INVENTION

[0013] As described above, the composite of the present invention is a composite in which a joining member is provided on the surface of a glass substrate, and the joining member has a seat portion, and the upper and lower surfaces of the seat portion are covered and fixed with a resin molded body containing a thermoplastic elastomer that is joined to the surface of the glass substrate. The joining member is a part that is provided on the back side of the display panel when the composite is used as, for example, a display panel for car navigation, and serves as a connecting part for fixing the display panel to the housing, and is formed with a seat portion that overlaps the surface of the glass substrate that is the display panel and a protrusion that protrudes upward from a part of the seat portion, and is fixed to the glass substrate in a state where a resin molded body containing a thermoplastic elastomer bonded to the surface of the glass substrate covers the seat portion.

[0014] When the joining member is fixed to a glass substrate via a resin material, if the glass substrate is thin, sink marks and undulations tend to appear on the surface of the glass substrate, even if the resin material is thin. This is thought to be because the contraction force of the resin material acting on the surface of the glass substrate as it hardens exceeds the force holding the glass substrate flat (the static force of the glass). This contraction force acts to locally deform the portion of the glass substrate where the resin material is provided into a convex shape, and this convex deformation is the cause of the sink marks and undulations that appear on the surface of the glass substrate. Therefore, it is thought that the occurrence of sink marks and undulations can be suppressed by selecting the resin material and using a resin such as an elastomer that has a low contraction force during molding.

[0015] Elastomers are soft polymers with rubber-like elasticity, and resin materials containing them are fluid at high temperatures, making them easy to process and strong even without fillers. By providing a resin molded body containing a thermoplastic elastomer at the joint between the joining member and the glass substrate, which is the aforementioned bonding site, the joining member can be stably fixed to the glass surface. In addition, the shrinkage force of the resin during molding is small, and is lower than the static force of the glass, making it possible to prevent sink marks and undulations from occurring on the glass surface. The lower and upper surfaces of the seat provided on the joining member are covered with the resin molded body, and the resin molded body is tightly attached to the periphery of the seat to enclose it, thereby increasing the fixing strength of the joining member and enabling the joining member to be firmly fixed to the glass substrate. The lower surface of the seat is the surface facing the glass substrate, and the upper surface is the surface on which the protrusion of the connecting member is located. Furthermore, if the seat of the joining member has a hole penetrating in the thickness direction and the hole contains a resin molded body, the joining member can be more firmly fixed to the glass substrate.

[0016] Examples of the thermoplastic elastomer contained in the resin molded product include styrene-based elastomers, vinyl chloride-based elastomers, olefin-based elastomers, urethane-based elastomers, polyester-based elastomers, nitrile-based elastomers, polyamide-based elastomers, etc. From the viewpoint of adhesion to the adhesive layer described below, styrene-based elastomers, urethane-based elastomers, and polyester-based elastomers are preferred, and polyester-based thermoplastic elastomers are particularly preferred. The resin molded article containing a thermoplastic elastomer is preferably a simple thermoplastic elastomer, but may also contain one or more known thermoplastic resins, such as ABS resin, polypropylene resin, polyamide resin, polycarbonate resin, POM resin, PMMA resin, PBT resin, and PC-ABS resin.

[0017] The tensile modulus of elasticity of a resin molded article made of a material containing a thermoplastic elastomer is preferably 100 MPa or less. If the tensile modulus is 100 MPa or less, the convex deformation of the glass is kept small, making the undulation less noticeable, or the shrinkage force of the resin is smaller than the static force of the glass, preventing the occurrence of undulation. If the tensile modulus is too small, the resin molded body becomes too soft and no longer functions as a part for fixing the joining member, making it difficult to join the joining member to a housing or the like and fix the glass substrate. Therefore, the lower limit of the tensile modulus of the resin molded body is preferably 2 MPa or more, more preferably 9 MPa or more, and the upper limit is preferably 70 MPa or less, more preferably 50 MPa or less.

[0018] The thermoplastic elastomer preferably has a rubber hardness of 95 or less. The rubber hardness referred to here refers to the rubber hardness on the A scale in accordance with JIS-K-6253, which is based on ISO7619-1. If the rubber hardness of a resin molded article made of a material containing a thermoplastic elastomer is 95 or less, the resin molded article is appropriately soft, and the transmission of the contraction force of the resin to the glass at the joint interface between the glass and the resin can be suppressed, preventing undulation. If the rubber hardness is 40 or more, the resin molded article has an appropriate hardness for use as a locking member. The lower limit of the rubber hardness is preferably 50 or more, and more preferably 55 or more. The upper limit is preferably 85 or less, and more preferably 80 or less.

[0019] Furthermore, it is preferable that the resin molding is formed on a part of the glass substrate, and that the flatness of a 15 mm square on the surface of the glass substrate opposite the part where the resin molding is formed is 20 μm or less. If the flatness of the surface of the glass substrate satisfies the above numerical conditions, undulations are not noticeable in appearance, and there is no effect on the display output of information and images on a display panel using the glass substrate.

[0020] The joining member is formed separately from the resin molded body using a synthetic resin material or a metal material that has greater rigidity (tensile strength, bending strength) than the resin molded body. By increasing the rigidity of the joining member, it is possible to ensure a degree of hardness that allows it to be fastened to the housing with a set screw or connected by a concave-convex fit. As the resin having a high rigidity (tensile strength and bending strength), it is preferable to use a resin material containing at least one of ABS resin, polycarbonate resin, and polybutylene terephthalate resin as a main component. As described above, the joining member is a portion that serves as a joining site for fixing the composite to a mounting member such as a housing, and is formed with a seat portion that overlaps the surface of the glass substrate and a protrusion that protrudes upward from the seat portion. The protrusion can be formed in an appropriate shape depending on the shape of the mounting member, such as a cylindrical boss type with a female thread if the mounting member has a threaded portion, or a rib type with a corresponding mounting or fitting site on its outer circumferential surface if the mounting member has an engaging or fitting recess. The seat of the joining member is disposed on the portion facing the glass substrate and extends outward from the protrusion. The seat of the joining member may extend from the entire periphery of the protrusion, or may extend from only a portion of the periphery. In order to increase the bonding strength between the seat portion of the joining member and the resin molded body, it is preferable that at least one hole be provided in the seat portion so as to penetrate through the seat portion in the thickness direction, and that the resin molded body is also present in this hole. It is more preferable that a plurality of holes be provided in the seat portion along the periphery of the protrusion.

[0021] The composite of the present invention can be constructed by laminating a printing layer and an adhesive layer in that order on a glass substrate, partially disposing the resin molding on the surface of the adhesive layer, and fixing a joining member to the resin molding. For example, when the composite of the present invention is a display panel for car navigation, the glass substrate can be constructed by forming a black printed layer in a strip shape along the four peripheral sides of a glass plate that is rectangular in plan view on the back side of the glass plate, laminating an adhesive layer on the surface of this printed layer, and forming the resin molded body on the surface of this adhesive layer.

[0022] The ink for forming the printing layer may be any ink that can be used for direct printing on a glass plate, and commercially available inks for printing on glass plates can be used. From the viewpoint of adhesion to glass, ink containing a silane coupling agent is preferred. The ink is used by adding a black colorant such as carbon black, and the printed layer forms a black colored portion on the surface of the glass plate.

[0023] The adhesive layer may be any material that can bond the printed layer to the resin molded article to be injection-molded. Commercially available binder inks and adhesion enhancers used in injection molding can be used.

[0024] The glass substrate having a printed layer and an adhesive layer laminated on one side of the glass plate preferably has a thickness of 0.2 mm or more and 2.0 mm or less, and more preferably 0.5 mm or less when used to curve glass and hold and fix it in a curved shape. If the thickness is 2.0 mm or less, the display panel can be easily made lighter, and 1.5 mm or less is more preferable, and 1.0 mm or less is even more preferable. Furthermore, if the thickness is 0.5 mm or less, the glass substrate can be processed to have a curved shape, and can be installed in a housing while maintaining the curved shape, which is preferable. If the thickness is 0.2 mm or more, the glass substrate is less likely to break even when curved, which is preferable.

[0025] Examples of the glass substrate include borosilicate glass, aluminosilicate glass, and aluminoborosilicate glass. Also included are low-alkali and non-alkali glasses of these glasses. Further examples include silica glass and soda-lime glass. Among these, borosilicate glass, aluminosilicate glass, aluminoborosilicate glass, and low-alkali glasses thereof are preferred, and non-alkali glasses thereof are more preferred. The glass substrate may be colorless or colored, but is preferably colorless and transparent in order to improve the visibility of the display.

[0026] The composite having the above configuration can be molded by inserting the glass substrate and the joining member into a molding die and filling the molding die with a resin containing a thermoplastic elastomer, thereby integrating each of them. In this case, as described above, it is preferable to provide at least one hole penetrating the seat portion of the joining member along its thickness direction, coat the upper and lower surfaces of the glass substrate and the seat portion of the joining member with a resin containing a thermoplastic elastomer to tightly surround the circumferential surface of the seat portion, and further to flow the resin into the hole to solidify and integrate the glass substrate, joining member, and resin. In addition, in producing the composite, it is preferable that the lower surface of the seat of the joining member facing the glass substrate is provided with unevenness by embossing or graining, or with grooves arranged in multiple rows or in a checkerboard pattern, so that the contact area with the resin containing the thermoplastic elastomer that is poured between the joining member and the glass substrate is increased.

[0027] The composite of the present invention can be used in display panels for devices that display various types of information and images. Examples of display devices include in-vehicle devices such as car navigation systems, smartphones, and other electronic devices equipped with panel displays such as liquid crystal displays and organic EL displays.

[0028] The composite of the present invention will be described below based on examples. The following examples are merely illustrative examples for embodying the technical concept of the present invention, and the present invention is not limited to the following embodiments.

[0029] FIG. 1 shows an example in which the composite of the present invention is applied to a display panel for a car navigation system. The display panel 1 in the illustrated form is formed by integrally fixing a plurality of joining members 3 and 4, which are joining portions, to the rear side of a glass substrate 2 having a horizontally long rectangular shape via a resin molding 5. The display panel 1 is attached integrally to the front of the car navigation housing (not shown) that houses the electronic devices, by connecting joining members 3 and 4, which are joining portions provided on the back side of the glass substrate 2, to joining portions provided on the front frame portion of the car navigation housing (not shown) that houses the electronic devices, thereby forming the display surface of the car navigation.

[0030] The glass substrate 2 is formed by providing black colored portions 22 in strips along the four peripheral sides of the rear surface of a transparent, horizontally elongated rectangular glass plate 21, and has an overall thickness of about 0.35 mm.

[0031] The colored portion 22 is formed by laminating an adhesive layer 22b on a printed layer 22a provided on the rear surface side of the glass plate 21.

[0032] In detail, the colored portion 22 is formed by applying an ink made of an acrylic urethane resin containing a black colorant and a silane coupling agent in a frame shape along the periphery of the rear side of the glass plate 21 to form a printed layer 22a, and after the printed layer 22a has dried, a two-component curing polyurethane ink is applied to its surface, which is then dried to form an adhesive layer 22b superimposed on the top surface of the printed layer 22a.

[0033] The joining members 3 and 4 are both made of a resin material whose main component is polycarbonate resin and has greater rigidity (tensile strength and bending strength) than the resin molded body 5 described below, and are formed into a shape with protrusions that join to the joining portion of the frame body. 3, the joining member 3 has a flat seat 31 that overlaps the glass plate 21 and has protrusions 32 that protrude from the seat 31. The protrusions 32 are shaped to engage with or fit into the joined portions. Holes 33 are formed on the front, back, left, and right sides of the protrusions 32, penetrating the seat 31 in the thickness direction. 5, the joining member 4 has a cylindrical protrusion 42 that engages with or fits into the joining portion protruding from a flat seat 41 that overlaps the glass plate 21. On the left and right sides of the protrusion 42, a hole 43 is formed that penetrates the seat 41 in the thickness direction. As shown in FIG. 1 , the bonding members 3 and 4 are fixed integrally to the surface of the glass substrate 2 via resin moldings 5, with the bonding member 3 being fixed to the center of the upper edge of the glass substrate 2 and the bonding members 4 being fixed to both the left and right edges of the glass substrate 2, on the surface of the colored portion 22 formed on the back side of the glass substrate 2.

[0034] The resin molding 5 is formed using a polyester-based thermoplastic elastomer that has a small shrinkage force during molding, and is integrally fixed to the surface of the glass substrate 2 at the portion where the joining members 3 and 4 of the glass substrate 2 are attached. More specifically, as shown in Figures 2 and 4, the resin molding 5 provided at the center of the upper edge of the glass substrate 2 has a flat receiving portion 51 whose underside is joined to the colored portion 22, and the seat portion 31 of the joining member 3 overlaps on the flat receiving portion 51, and the outer peripheral side and upper surface of this seat portion 31 are tightly covered by the holding portion 52. In addition, resin is poured into the hole portion 33 formed in the seat portion 31, and the seat portion 31 of the joining member 3 is solidified and integrated with the resin molding 5. As shown in FIG. 6, the resin molding 5 provided on both the left and right sides of the glass substrate 2 is also configured in the same manner as described above, with the seat portion 41 of the joining member 4 overlapping the flat receiving portion 51 whose underside is joined to the colored portion 22, and the outer peripheral side and upper surface of this seat portion 41 are tightly covered by the holding portion 52, and resin is poured into the hole 43 formed in the seat portion 41, so that the seat portion 41 of the joining member 4 is solidified and integrated with the resin molding 5.

[0035] As described above, in the display panel 1 of this embodiment, the joining members 3, 4 formed using a resin material with high rigidity are attached to the surface of the glass base material 2 via a resin molded body 5 formed using a resin material with low shrinkage force during molding. This prevents sink marks and undulations from appearing on the surface of the glass base material 2 during molding, even if the glass base material 2 is thin. On the other hand, by tightly covering the entire peripheral surfaces, including the upper surfaces of the seat portions 31, 41 of the joining members 3, 4, with the resin molded body 5, the joining members 3, 4 are firmly fixed to the surface of the glass base material 2, ensuring a rigidity sufficient to firmly bond them to the joining portions of the housing.

[0036] A display panel 1 having such a configuration can be molded, for example, by inserting a glass substrate 2 and bonding members 3 and 4 into a molding die, filling the molding die with molten resin of the resin molding body 5, and integrating them together. That is, molding can be performed through a process including the steps of inserting the glass substrate 2 and the bonding members 3 and 4 into a molding die, closing the molding die and injection-molding the molten resin of the resin molding 5 between the glass substrate 2 and the bonding members 3 and 4 and onto the upper surfaces of the seat portions 31 and 41 of the bonding members 3 and 4, and opening the molding die and removing the display panel 1 with the bonding members 3 and 4 fixed to the surface of the glass substrate 2.

[0037] Although the embodiment in which a synthetic resin joining member is fixed to a glass substrate has been described, the present invention can also be applied to an embodiment in which a metal joining member is fixed to a glass substrate. In this case, the metal joining member preferably has a seat and a protrusion, as described above, and the seat preferably has one or more holes. In the illustrated embodiment, the composite of the present invention is applied to a display panel for a car navigation system, but it can also be applied to display panels for other information display devices. In this case, the display panel is formed to a size corresponding to the display device, and an appropriate number of bonding members are provided on the back side of the glass substrate at appropriate positions on the back side of the glass substrate according to the size of the display device. The shapes and combinations of the glass substrate, joining member, and resin molded body that constitute the composite of the present invention are merely examples, and various modifications can be made based on design requirements and the like within the scope of the present invention. [Explanation of symbols]

[0038] 1 composite (face panel), 2 glass substrate, 21 glass plate, 22 colored portion, 22a printed layer, 22b adhesive layer, 3, 4 joining member, 31, 41 seat portion, 32, 42 protrusion portion, 33, 43 hole portion, 5 resin molded body

Claims

1. A composite in which a bonding member is provided on a surface of a glass substrate, The joining member has a seat portion, and the lower and upper surfaces of the seat portion are covered and fixed with a resin molded body containing a thermoplastic elastomer bonded to the surface of a glass substrate.

2. 2. The composite according to claim 1, wherein the seat portion has a hole penetrating therethrough in a thickness direction, and the resin molding is also contained in the hole.

3. 3. The composite according to claim 1, wherein the resin molding is a polyester-based thermoplastic elastomer.

4. 3. The composite according to claim 1, wherein the resin molded body has a tensile modulus of elasticity of 100 MPa or less.

5. 3. The composite according to claim 1, wherein the joining member is made of a synthetic resin or a metal.

6. 6. The composite according to claim 5, wherein the synthetic resin material of the joining member is mainly composed of at least one of ABS resin, polycarbonate resin, and polybutylene terephthalate resin.

7. 3. The composite according to claim 1, wherein a printed layer and an adhesive layer are laminated on a part of the surface of the glass substrate, and a resin molded body is disposed on the surface of the adhesive layer.

8. 3. The composite according to claim 1, wherein the glass substrate has a thickness of 0.2 to 2.0 mm.

9. A method for producing the composite of claim 1 or 2, comprising: Inserting a glass substrate and a bonding member into a molding die; a step of closing the molding die and injecting a resin molding into the space between the glass substrate and the joining member and on the upper surface of the seat portion of the joining member; a step of opening the molding die and removing a composite in which the bonding member is fixed to the surface of the glass substrate; A method for producing a composite, comprising:

10. A display device using the composite of claim 1 or 2 as a display panel.

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