JP6331127B2 - Cover glass and display device with cover glass - Google Patents

Description

  The present invention relates to a cover glass provided on a display device. The present invention also relates to a display device provided with a cover glass.

  Conventionally, it is known to provide a cover glass for protecting the display surface of a display device on the viewer side of a display device such as a liquid crystal display or an organic EL display. When the touch panel function is mounted on the display device, the cover glass also serves to protect the display device and a touch panel sensor provided on the viewer side of the display device. Note that a cover glass and a touch panel sensor are integrally formed.

  In recent years, mobile terminals with display devices such as smartphones and tablet PCs have been widely used. In a portable terminal, durability against a drop impact generated in a use environment is required. Therefore, the cover glass that protects the display device is required to have a high strength that can withstand a frequently occurring impact. Under such a background, for example, Patent Document 1 proposes that a cover glass is configured using a tempered glass having a compressive stress layer on which a compressive stress is generated.

  In patent document 1, the cover glass which has a dimension corresponding to the dimension of each display apparatus is produced by dividing | segmenting large tempered glass into pieces. By the way, the compressive stress layer of tempered glass is formed on the glass surface by chemical treatment or heat treatment. Therefore, when a large tempered glass is divided as in Patent Document 1, a tensile stress layer in which a tensile stress is generated is exposed on the side surface of the obtained cover glass. For this reason, it is considered that a cover glass having sufficient strength on the side surface cannot be manufactured by the method described in Patent Document 1.

  On the other hand, a technique has been proposed in which the strength of the side surface of the cover glass is increased by providing a resin on the side surface of the cover glass. For example, Patent Document 2 proposes that the outer peripheral surface of the cover glass including the side surface of the cover glass is bordered by a plastic film. As the edging method, an injection molding method, a dispensing method, a spray coating method, a roller coating method, and the like have been proposed. Examples of the material of the plastic film include an epoxy resin or an acrylic resin.

JP 2012-88946 A JP 2012-111688 A

  When the outer peripheral surface of the cover glass is bordered by a plastic film as described in Patent Document 2, the resin material constituting the plastic film is exposed to an external environment such as the atmosphere. On the other hand, when the resin material is provided in a predetermined place, usually, first, the resin material adjusted to have a predetermined fluidity is applied on the object, and then a polymerization reaction of the resin material is caused. A step of curing or solidifying the resin material is performed. Therefore, the plastic film provided on the outer peripheral surface of the cover glass is formed based on a polymerization reaction that has proceeded in an environment exposed to an external environment such as the atmosphere. On the other hand, acrylic resins generally have high reactivity. For this reason, when a plastic film is formed using an acrylic resin, the polymerization reaction is inhibited by oxygen, and as a result, the polymerization reaction cannot sufficiently proceed, and it is considered that sufficient hardness of the plastic film cannot be obtained. .

  Further, the plastic film provided on the outer peripheral surface of the cover glass is required to have a sufficiently high hardness so that the cover glass can be protected from impact. On the other hand, if the hardness of the plastic film is too high, the plastic film becomes brittle, and as a result, the toughness of the plastic film decreases. On the other hand, the epoxy resin generally has a high hardness, for example, a hardness of around D90. For this reason, it is considered that it is inappropriate to use an epoxy-based resin in the application of a cover glass to which an impact can be frequently applied. “D90” means that the hardness value obtained by measuring with a type D durometer is 90.

  The present invention has been made in consideration of such points, and an object of the present invention is to provide a cover glass having a reinforcing portion made of an appropriate resin material and a display device with the cover glass.

  The present invention is a cover glass provided in a display device, including a first surface, a second surface opposite to the first surface, and a side surface extending between the first surface and the second surface, A unit base made of glass, and a reinforcing part provided on a side surface of the unit base material and containing a resin material, wherein the resin material of the reinforcing part contains an ene compound and a thiol compound. A cover glass having a photocurable resin.

  The cover glass by this invention WHEREIN: The decoration part which exhibits a predetermined color may be provided on the surface of the said reinforcement part at least partially.

  In the cover glass according to the present invention, the polyene-polythiol-based photocurable resin of the resin material of the reinforcing portion may include 20 to 80% by weight of an ene compound and 20 to 80% by weight of a thiol compound. .

  This invention is a display apparatus with a cover glass provided with a display apparatus and the cover glass arrange | positioned at the said display apparatus, and the said cover glass consists of a cover glass of the said description.

  ADVANTAGE OF THE INVENTION According to this invention, the cover glass provided with the reinforcement part which has appropriate hardness and toughness can be provided.

FIG. 1 is a developed view showing a display device with a cover glass in an embodiment of the present invention. FIG. 2 is a plan view showing a touch panel sensor unit provided on the cover glass of FIG. 1. FIG. 3 is a cross-sectional view of the cover glass of FIG. 2 along the line III. 4 is a cross-sectional view of the cover glass of FIG. 2 taken along line IV. FIG. 5 is an enlarged cross-sectional view illustrating a side surface of the cover glass of FIG. 3. FIG. 6A is a diagram showing a part of a step of forming a unit laminate having a unit substrate and a protective film using a substrate made of large tempered glass. FIGS. 6B (a) and 6 (b) are diagrams showing a part of a step of forming a unit laminate body having a unit base material and a protective film using a base material made of large tempered glass. FIG. 6C is a diagram showing a part of a step of forming a unit laminate having a unit base material and a protective film using a base material made of large tempered glass. FIGS. 6D (a) and 6 (b) are diagrams showing a part of a step of forming a unit laminate body having a unit base material and a protective film using a base material made of large tempered glass. FIGS. 6E (a) and 6 (b) are diagrams showing a part of a process of forming a unit laminate body having a unit base material and a protective film using a base material made of large tempered glass. FIG. 7A is a diagram illustrating a part of a process for obtaining a cover glass whose side surface is reinforced by providing a resin on a side surface of a unit base material of the unit laminate body. FIG. 7B is a diagram illustrating a part of a process for obtaining a cover glass whose side surface is reinforced by providing a resin on a side surface of a unit base material of the unit laminate body. FIG. 7C is a diagram showing a part of a process for obtaining a cover glass whose side surface is reinforced by providing a resin on the side surface of the unit base material of the unit laminate body. FIG. 7D is a diagram showing a part of a process for obtaining a cover glass whose side surface is reinforced by providing a resin on the side surface of the unit base material of the unit laminate body. FIG. 8 is a cross-sectional view showing a cover glass in a first modification of the present embodiment. FIG. 9 is a cross-sectional view showing a cover glass in a second modification of the present embodiment. FIG. 10 is a cross-sectional view showing a cover glass in a third modification of the present embodiment. FIG. 11 is a cross-sectional view showing a cover glass in a fourth modification of the present embodiment. FIG. 12 is a cross-sectional view showing a cover glass in a fifth modification of the present embodiment. FIG. 13: is sectional drawing which shows the cover glass in the 6th modification of this Embodiment. FIG. 14 is a diagram illustrating an example in which a reinforcing portion is formed on a wall surface of a through hole formed in a unit base material. FIG. 15 is a diagram showing a step of forming the reinforcing portion 26 on the wall surface a of the through hole shown in FIG. 16A to 16D are diagrams showing a method for evaluating the printability of a resin in Example 2. FIG. FIG. 17 is a diagram illustrating a method for evaluating the impact resistance of a resin in Example 3.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 7D. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual ones.

(Display device with cover glass)
First, the display device 10 with a cover glass will be described with reference to FIG. As shown in FIG. 1, the display device 10 with a cover glass is configured by combining a display device 15 and a cover glass 20. The illustrated display device 15 is configured as a flat panel display. The display device 15 includes a display panel 16 having a display surface 16 a and a display control unit (not shown) connected to the display panel 16. The display panel 16 includes an active area A1 that can display an image, and an inactive area (also referred to as a frame area) A2 that is disposed outside the active area A1 so as to surround the active area A1. . The display control unit processes information regarding the video to be displayed, and drives the display panel 16 based on the video information. The display panel 16 displays a predetermined image on the display surface 16a based on a control signal from the display control unit. That is, the display device 15 plays a role as an output device that outputs information such as characters and drawings as video.

  As shown in FIG. 1, the cover glass 20 is disposed on the display surface 16 a of the display panel 16 on the viewer side of the display device 15. For example, the cover glass 20 is bonded to the display surface 16a of the display device 15 via an adhesive layer (not shown). In FIG. 1, the surface (first surface) on the display device side of the cover glass 20 is represented by reference numeral 20a, and the surface (second surface) on the observer side is represented by reference numeral 20b.

  In the present embodiment, the cover glass 20 is configured to provide not only a function of protecting the display device 15 but also a touch panel function. Specifically, on the first surface 20a of the cover glass 20 on the display device 15 side, a touch panel sensor unit 40 including a sensor electrode for detecting the approach or contact of the external conductor is provided. Moreover, the 1st decorating part 60 for exhibiting a desired color is further provided in the inactive area Aa2 of the 1st surface 20a of the cover glass 20. As shown in FIG.

(Touch panel sensor)
Next, the touch panel sensor unit 40 provided on the first surface 20a of the cover glass 20 will be described with reference to FIG. FIG. 2 is a plan view showing the cover glass 20 as viewed from the first surface 20a side. In FIG. 2, the first decorating unit 60 is omitted for convenience of explanation.

  As shown in FIG. 2, the first surface 20a of the cover glass 20 corresponds to the active area Aa1 corresponding to the active area A1 and the inactive area A2 of the display panel 16, and the active area Aa1 corresponding to the area where the touch position can be detected. It is partitioned into an inactive area Aa2 located around the area Aa1. In addition, the touch panel sensor unit 40 is connected to the plurality of sensor electrodes 41 and 42 disposed in the active area Aa1 and the corresponding sensor electrodes 41 and 42, and is disposed in the inactive area Aa2 of the cover glass 20. The lead-out wiring 43 and a plurality of terminal portions 44 connected to the corresponding lead-out wiring 43 are provided.

  As shown in FIG. 2, the sensor electrodes 41 and 42 include a plurality of first sensor electrodes 41 extending along the first direction D1, and a plurality of second electrodes extending along a second direction D2 orthogonal to the first direction D1. Sensor electrode 42. Each of the sensor electrodes 41 and 42 may include line portions 41a and 42a extending linearly and bulging portions 41b and 42b bulging from the line portions 41a and 42a.

  The lead-out wiring 43 is provided in the inactive area Aa2 in order to transmit the signals detected by the corresponding sensor electrodes 41 and 42 to the terminal portion 44. The signal transmitted to the terminal unit 44 by the extraction wiring 43 is transmitted to the detection control unit via a flexible substrate (not shown) attached to the terminal unit 44.

(Layer structure of cover glass, touch panel sensor and decoration)
Next, with reference to FIG. 3 and FIG. 4, the layer structure of the touchscreen sensor part 40 and the 1st decoration part 60 provided in the 1st surface 20a of the cover glass 20 and the cover glass 20 is demonstrated. 3 and 4 are cross-sectional views taken along line III and line IV, respectively, of the cover glass 20 shown in FIG.

  First, the layer configuration of the components arranged in the active area Aa1 of the cover glass 20 will be described. As shown in FIGS. 3 and 4, the first line portion 41 a, the first bulge portion 41 b, and the second bulge portion 42 b of the touch panel sensor unit 40 may be formed on the same plane. In this case, the first line portion 41a, the first bulging portion 41b, and the second bulging portion 42b are simultaneously formed by patterning the transparent conductive layer 51 made of a transparent conductive material such as indium tin oxide (ITO). It is possible. The first line portion 41a and the second line portion 42a are formed so as to partially overlap each other when viewed from the normal direction of the cover glass 20, and between the first line portion 41a and the second line portion 42a. Insulating layer 47 is interposed.

  Next, the layer configuration of the components arranged in the inactive area Aa2 of the cover glass 20 will be described. As shown in FIGS. 3 and 4, the first decorative portion 60 is arranged in the inactive area Aa <b> 2 so as to be positioned closer to the observer side than the above-described extraction wiring 43. In this case, the 1st decoration part 60 is visually recognized through the cover glass 20 from the observer side. That is, in the display device 10 with the cover glass, the appearance of the inactive area Aa2 is determined by the first decorating unit 60 and its surrounding components.

  The color of the 1st decorating part 60 is selected according to the design property calculated | required with respect to the display apparatus 10 with a cover glass. For example, black, white, light blue, pink, green, etc. can be mentioned as an example of the color of the 1st decorating part 60. Although the material which comprises the 1st decorating part 60 is determined according to the selected color, for example, when white is calculated | required, the 1st decorating part 60 is disperse | distributed in the binder which consists of a resin material, and a binder. And a colored pigment such as titanium oxide. As the binder, for example, a resin such as an acrylic resin, an epoxy resin, a polyurethane resin, a polyamide resin, or a mixture of these resins can be used as appropriate.

  By the way, in the manufacturing process of the cover glass 20, when providing the 1st decorating part 60 on the unit base material 22 or the base material 30 mentioned later first, and then providing the reinforcement part 26 in the side surface 22c of the unit base material 22, As shown in FIGS. 3 and 4, the first decorative portion 60 cannot spread to the side surface 20 c of the cover glass 20, that is, to the side surface 26 c of the reinforcing portion 26. For this reason, the design effect by the first decorative portion 60 does not reach the side surface 20 c of the cover glass 20, for example, the reinforcing portion 26. In consideration of this point, as shown in FIG. 3 and FIG. 4, the unit base 22 is located on the first surface 22 a side or the first surface 26 a side of the reinforcing portion 26 and outside the first decorating portion 60. The 2nd decoration part 62 may be provided. The 2nd decoration part 62 is comprised so that a predetermined color may be exhibited. By further providing such a second decorative portion 62, the range of the non-active area Aa2 that can exhibit a desired color is expanded to the outside, and design improvements such as prevention of light leakage from the outer peripheral portion are improved. Can be planned. Preferably, the 2nd decoration part 62 is comprised so that it may overlap with the reinforcement part 26, when it sees along the normal line direction of the 1st surface 20a of the cover glass 20. As shown in FIG. More preferably, the 2nd decoration part 62 is comprised so that it may reach even to the side surface 20c of the cover glass 20, when it sees along the normal line direction of the 1st surface 20a of the cover glass 20. As shown in FIG.

  The color which the 2nd decoration part 62 exhibits is not specifically limited, According to the effect on the design requested | required, it sets suitably. For example, the 2nd decoration part 62 may be comprised with the material same as the 1st decoration part 60 so that the 1st decoration part 60 may exhibit the same color, or is different from the 1st decoration part 60. It may be configured to exhibit a color. As a method of providing the second decorating part 62, various known methods can be adopted. For example, after the reinforcing part 26 is formed, a coating liquid containing a material constituting the second decorating part 62 is screen-printed. A method of coating the first surface 26a of the reinforcing portion 26 by a printing method such as a method is employed. When the printing method is used, examples of the solvent for constituting the coating liquid include ethers, ketones, esters, alcohols, polyhydric alcohols, aromatic hydrocarbons, and the like. Further, the surface tension of the coating solution is adjusted within a range of 20 to 40 mN / m, for example.

  Next, the configuration of the cover glass 20 will be described. As shown in FIGS. 3 and 4, the cover glass 20 includes a unit base material 22 and a reinforcing portion 26. The unit base member 22 includes a first surface 22a on the display device side, a second surface 22b opposite to the first surface 22a, and a side surface 22c extending between the first surface 22a and the second surface 22b. Yes. The reinforcing portion 26 is provided on the side surface 22 c of the unit base material 22.

  As will be described later, the unit base material 22 is obtained by dividing the base material 30 made of large tempered glass into pieces. As shown in FIG. 5, the unit base material 22 includes a compressive stress layer 24a formed on the first surface 22a and the second surface 22b, a compressive stress layer 24a on the first surface 22a side, and a second surface 22b side. And a tensile stress layer 24b located between the compressive stress layer 24a. The compressive stress layer 24a is a layer in which compressive stress is generated, and the tensile stress layer 24b is a layer in which tensile stress is generated. As a method for generating the compressive stress layer 24a and the tensile stress layer 24b, physical strengthening (wind cooling strengthening) and chemical strengthening are known. For example, in chemical strengthening, a chemical treatment is performed in which alkali ions contained in glass are exchanged with other alkali ions having a larger ionic radius at a temperature below the strain point. Thereby, compressive stress can be generated near the surface layer where the ions are exchanged. By forming the compressive stress layer 24a, some kind of impact is applied to the first surface 22a or the second surface 22b, and thereby a scratch such as a crack is formed on the first surface 22a or the second surface 22b. Even can prevent the wound from expanding. For this reason, the 1st surface 22a and the 2nd surface 22b of the unit base material 22 have the high tolerance with respect to an impact. As a material constituting the unit base member 22, for example, aluminosilicate glass can be used. The thickness of the compressive stress layer 24a is generally in the range of 10 to 100 μm.

  On the other hand, as shown in FIG. 5, the tensile stress layer 24 b of the unit base material 22 reaches the side surface 22 c of the unit base material 22. That is, the tensile stress layer 24 b is exposed on the side surface 22 c of the unit base material 22. For this reason, the side surface 22c of the unit base material 22 is weak against damage such as cracks, compared to the first surface 22a and the second surface 22b of the unit base material 22. The reinforcing portion 26 described above is provided to protect the side surface 22c of the unit base material 22 as described above.

  As the material constituting the reinforcing portion 26, for example, a curable resin that is cured by a polymerization reaction by heating or ultraviolet irradiation is used. In this case, the reinforcing part 26 has a desired fluidity at the time of molding before curing, and the reinforcing part 26 has a desired hardness and strength after curing. This makes it possible to achieve both formability, hardness and strength.

By the way, in this Embodiment, the reinforcement part 26 is exposed at least partially with respect to external environments, such as air | atmosphere. For this reason, the polymerization reaction when the reinforcing portion 26 is cured proceeds in an environment where the reinforcing portion 26 is exposed to the external environment such as the atmosphere. For this reason, when a resin material having a high reactivity is generally used, such as an acrylic resin, the polymerization reaction is inhibited by oxygen, and as a result, the polymerization reaction cannot proceed sufficiently, and therefore the reinforcing portion having sufficient hardness. 26 cannot be obtained.
Further, if a resin material having an excessively high hardness such as an epoxy resin is used, it is considered that the reinforcing portion 26 becomes brittle, and as a result, defects or the like frequently appear in the reinforcing portion 26. That is, it is considered that the toughness of the reinforcing portion 26 is lowered.
Further, as described above, when the second decorative portion 62 is formed on the reinforcing portion 26 after the reinforcing portion 26 is provided on the side surface 22c of the unit base member 22, the second decorative portion 62 may be a screen printing method or the like. It is formed by a printing method or the like. For this reason, in order for the 2nd decoration part 62 to be stably hold | maintained on the reinforcement part 26, the reinforcement part 26 is predetermined wettability with respect to the material which comprises the 2nd decoration part 62, ie, printability. It is required to have.

  As a result of intensive experiments conducted by the present inventors, as supported by the examples described later, the resin material contained in the reinforcing portion 26 is a polyene-polythiol resin, more preferably a polyene-polythiol photocurable resin. Found that is suitable. The polyene-polythiol-based photocurable resin is a polyene-polythiol-based resin that is configured so that a polymerization reaction proceeds due to light irradiation. Hereinafter, characteristics of the polyene-polythiol-based photocurable resin will be described. The polyene-polythiol-based photocurable resin contains an ene compound, a thiol compound, and a photopolymerization initiator. Such a polyene-polythiol-based photocurable resin has an advantage that it is not subjected to polymerization inhibition due to oxygen as compared with an acrylic photocurable resin. The polyene-polythiol-based photocurable resin has an appropriate hardness that can protect the unit base material 22 from impact and does not become brittle. For example, a polyene-polythiol-based photocurable resin that has undergone an appropriate polymerization reaction has a hardness in the range of D50 to D75. In the present application, “appropriately undergoing a polymerization reaction” means that the polymerization reaction was carried out under the conditions recommended by the material manufacturer providing the resin material.

  The constituent ratio of the ene compound and the thiol compound in the polyene-polythiol-based photocurable resin is appropriately determined according to the required characteristics. For example, the polyene-polythiol-based photocurable resin is 20 to 80% by weight of the ene compound. 20 to 80% by weight of a thiol compound. The sum of the weight% of the ene compound and the weight% of the thiol compound may be 100.

  In addition, the polyene-polythiol-based photocurable resin also has an advantage of less curing shrinkage than the acrylic photocurable resin. Hereinafter, the relationship between the cover glass 20 according to the present embodiment and curing shrinkage will be described.

  As will be described later, the reinforcing portion 26 is formed by curing the coating liquid 27. For this reason, if a large shrinkage occurs when the coating liquid 27 is cured, the accuracy of the size of the reinforcing portion 26 is lowered. Moreover, when large shrinkage arises, the adhesiveness between the reinforcement part 26 and the unit base material 22 will also fall. Further, when large shrinkage occurs in the thickness direction of the unit base material 22 (the normal direction of the first surface 22a and the second surface 22b of the unit base material 22), the surfaces 26a and 26b of the reinforcing portion 26 and the unit base material 22 A large step is generated between the surfaces 22a and 22b, and as a result, the boundary between the reinforcing portion 26 and the unit base member 22 is easily visually recognized by an observer. Therefore, the resin material constituting the reinforcing portion 26 is preferably a material that is as small as possible when shrinking when cured. According to the present embodiment, the thickness of the unit base material 22 is 700 μm even when shrinkage occurs during curing by configuring the reinforcing portion 26 using a polyene-polythiol-based photocurable resin. In this case, the step generated between the surfaces 26a and 26b of the reinforcing portion 26 and the surfaces 22a and 22b of the unit base member 22 can be suppressed within a range of 1 to 10 μm, for example.

  As will be described later, the thickness of the compressive stress layer 24a is generally in the range of 10 to 100 μm. Therefore, selecting a material having a small shrinkage when cured and thereby suppressing the step between the unit base material 22 and the reinforcing portion 26 within the range of 1 to 10 μm respectively means that the degree of shrinkage is that of the compressive stress layer 24a. It leads to become smaller than thickness. For this reason, even if the reinforcing portion 26 contracts during curing, it is possible to prevent the tensile stress layer 24b from being exposed on the side surface 20c of the cover glass 20 or a wall surface 23c of a through hole 23 described later.

  Hereinafter, the composition of the polyene-polythiol-based photocurable resin will be described in detail.

An ene compound is a polyfunctional compound having two or more carbon-carbon double bonds in one molecule. Vinyl ethers, vinyl esters, allyl ethers, allyl alcohol derivatives, allyl isocyanuric acid derivatives, styrenes , Acrylic acid derivatives, methacrylic acid derivatives, divinylbenzene and the like. When a part of the above-mentioned ene compounds is arranged in the order of high reactivity with the thiol compound, the order becomes vinyl ethers, vinyl esters, allyl ethers, allyl isocyanuric acid derivatives, acrylic acid derivatives, and styrenes.
The thiol compound is a compound having two or more thiol groups in one molecule, and examples thereof include esters of mercaptocarboxylic acid and a polyhydric alcohol, aliphatic polythiols and aromatic polythiols, and other polythiols. These 1 type (s) or 2 or more types can be used.
Examples of the mercaptocarboxylic acid in the ester of mercaptocarboxylic acid and polyhydric alcohol include thioglycolic acid, α-mercaptopropionic acid and β-mercaptopropionic acid.

  The blend ratio of the ene compound (a) and the thiol compound (b) is such that the ratio of the number of unsaturated bonds of the ene compound (a) to the number of thiol groups of the thiol compound (b) is 2: 1 to 1: 2. A range is preferable. When the amount of thiol groups exceeds 1: 2, a large amount of unreacted thiol groups remain in the composition after the curing reaction. It is not preferable from the viewpoint that there are few advantages such as high adhesion and no polymerization inhibition due to oxygen.

  A photoinitiator is not specifically limited, A well-known photoinitiator can be used. Specifically, for example, as a photopolymerization initiator, in the case of a resin system having a radical polymerizable unsaturated group, it is commercially available as acetophenones (for example, trade name Irgacure 184 (manufactured by Ciba Specialty Chemicals) 1 -Hydroxy-cyclohexyl-phenyl-ketone), benzophenones, thioxanthones, propiophenones, benzyls, acylphosphine oxides, benzoin, benzoin methyl ether and the like can be used alone or in combination.

  It is preferable to add the said photoinitiator (c) in the ratio of 0.001-10 mass% with respect to the total amount of the said ene compound (a) and a thiol compound (b). If it is less than 0.001% by mass, there may be a problem that the photopolymerization reaction cannot be sufficiently caused. Moreover, even if it adds exceeding 10 mass%, the improvement of an effect is not seen.

  Next, with reference to FIG. 5, the shape of the side surface 22c of the unit base material 22 and the reinforcement part 26 is demonstrated in detail. FIG. 5 is an enlarged cross-sectional view of the side surface 20c of the cover glass 20 of FIG.

  First, the shape of the reinforcing portion 26 will be described. As shown in FIG. 5, the reinforcing portion 26 includes a first surface 26 a that extends from the vicinity of the end 22 ae of the first surface 22 a on the same plane as the first surface 22 a of the unit substrate 22, and the unit substrate 22. The second surface 22b extends from the vicinity of the end 22be of the second surface 22b to the side on the same plane as the second surface 22b and between the first surface 26a and the second surface 26b of the reinforcing portion 26. Side surface 26c. Hereinafter, an advantage provided by the reinforcing portion 26 including the first surface 26a and the second surface 26b will be described.

  First, for comparison, problems considered in the above-mentioned Patent Document 2 will be described. When providing a reinforcing portion that reinforces the side surface of the base material by trimming the outer peripheral surface of the base material as in Patent Document 2, a step is formed between the surface of the reinforcing portion and the surface of the base material. . Therefore, light is likely to be scattered at the boundary between the reinforcing portion and the base material, and the light transmittance and reflectance are likely to change greatly. As a result, the boundary between the reinforcing portion and the base material is easily visually recognized by the observer. That is, it is conceivable that the design properties of the cover glass deteriorate. Moreover, when the reinforcement part of a cover glass is exposed outside, the operation feeling of a touch panel will be inhibited by the level | step difference.

  On the other hand, according to this Embodiment, the 1st surface 22a of the unit base material 22 and the 1st surface 26a of the reinforcement part 26 are located on the same plane. Similarly, the 2nd surface 22b of the unit base material 22 and the 2nd surface 26b of the reinforcement part 26 are located on the same plane. That is, there is no or almost no step between the unit base member 22 and the reinforcing portion 26. Specifically, the steps between the first surface 22a and the second surface 22b of the unit base member 22 and the first surface 26a and the second surface 26b of the reinforcing portion 26 are each 10 μm or less. For this reason, it can suppress that the boundary between the unit base material 22 and the reinforcement part 26 is visually recognized by an observer. Therefore, according to the reinforcement part 26 of this Embodiment, ensuring of the intensity | strength of the side surface 20c of the cover glass 20 and ensuring of the design property of the cover glass 20 can be made to make compatible. In addition, the operational feeling of the touch panel is not hindered by the steps. As described above, the thickness of the compressive stress layer 24a is generally in the range of 10 to 100 μm. Therefore, when the step between the first surface 22a and the second surface 22b of the unit base member 22 and the first surface 26a and the second surface 26b of the reinforcing portion 26 is 10 μm or less, that is, the step is the compressive stress layer 24a. When the thickness is smaller than the thickness, the compressive stress layer 24a of the unit base material 22 and the reinforcing portion 26 overlap at least partially on the side surface 22c of the unit base material 22. Therefore, the tensile stress layer 24 b exposed on the side surface 22 c of the unit base material 22 can be covered with the reinforcing portion 26 without a gap. For this reason, the impact resistance of the cover glass 20 can be increased more reliably.

  Preferably, the first surface 26a and the second surface 26b of the reinforcing portion 26 are respectively on the same plane as the first surface 22a and the second surface 22b of the unit base member 22 from the end 22ae and the end 22be over at least 300 μm. It extends toward. Thereby, the intensity | strength of the side surface 20c of the cover glass 20, and the designability of the cover glass 20 can be ensured more reliably. Note that “on the same plane” extends from the end 22ae and the end 22be to the side over at least 300 μm of the first surface 26a and the second surface 26b of the reinforcing portion 26, as in the case of the above-described step. This means that the distance in the thickness direction of the unit base material 22 between the portion and the first surface 22a and the second surface 22b of the unit base material 22 is 10 μm or less.

  Next, the side surface 26c of the reinforcing part 26 will be described. In FIG. 5, the end portion of the first surface 26a of the reinforcing portion 26 is represented by reference numeral 26ae, and the end portion of the second surface 26b of the reinforcing portion 26 is represented by reference numeral 26be. As shown in FIG. 5, the side surface 26 c is configured as a flat surface that extends substantially flat between the end portion 26 ae and the end portion 26 be. The first surface 26a and the side surface 26c intersect at a substantially right angle, and similarly, the second surface 26b and the side surface 26c intersect at a substantially right angle. That is, in the present embodiment, the position of the end portion 26ae and the position of the end portion 26be in the left-right direction in FIG. 5 (the direction in which the first surface 26a and the second surface 26b extend) match.

Next, the shape of the side surface 22c of the unit base material 22 will be described. As shown in FIG. 5, the side surface 22c of the unit base member 22 includes a first side surface 22d and a second side surface 22e. The first side surface 22d intersects the end 22ae of the first surface 22a of the unit base material 22, and spreads outward as it goes to the second surface 22b side of the unit base material 22. Further, the second side surface 22e intersects the end 22be of the second surface 22b of the unit base member 22, expands outward toward the first surface 22a side of the unit base member 22, and joins the first side surface 22d. Yes. For this reason, the confluence | merging part of 22 d of 1st side surfaces and the 2nd side surface 22e will protrude outside. In this case, since the reinforcing portion 26 sandwiches the side surface 22c of the unit base material 22, the reinforcing portion 26 can be firmly adhered to the side surface 22c of the unit base material 22.
The first side surface 22d and the second side surface 22e having such a shape, for example, when the base material 30 is divided and the unit base material 22 is obtained by dividing the base material 30, as described later, are provided. The substrate 30 is formed by wet etching from both sides.

(Dimension of cover glass)
Next, the dimensions of the cover glass 20 will be described. First, the covering dimension of the reinforcing portion 26 provided on the side surface 22c of the unit base material 22 will be described. Here, the covering dimension is the length of the reinforcing portion 26 in the direction along the normal direction of the side surface 26c of the reinforcing portion 26. The normal direction of the side surface 26c of the reinforcing portion 26 is parallel to the left-right direction in FIG.

  In FIG. 5, the minimum value of the covering dimension of the reinforcing portion 26 is represented by the symbol Tmin. In the present embodiment, as described above, the first side surface 22d of the unit base member 22 spreads outward toward the second surface 22b side. Moreover, the 2nd side 22e of the unit base material 22 has spread outside as it goes to the 1st surface 22a side. As described above, the side surface 26c of the reinforcing portion 26 is a flat surface that intersects the first surface 26a and the second surface 26b at a right angle. Therefore, as shown in FIG. 5, at the position where the first side surface 22d and the second side surface 22e merge, the covering dimension of the reinforcing portion 26 becomes the minimum value Tmin.

  The minimum value Tmin of the covering dimension of the reinforcing portion 26 is appropriately set so that the side surface 22c of the unit base material 22 can be protected even when an impact is applied to the side surface 20c of the cover glass 20 or the like. Yes. For example, the minimum value Tmin of the covering dimension of the reinforcing portion 26 is set to 20 μm or more.

  Further, in the present embodiment, the covering dimension of the reinforcing portion 26 becomes the maximum value at the position of the first surface 26a or the position of the second surface 26b. By the way, if the maximum value of the covering dimension of the reinforcing portion 26 becomes too large, it is considered that the reinforcing portion 26 is easily peeled off from the unit base material 22 when an impact is applied to the cover glass 20. Moreover, since the ratio of the glass in the cover glass 20 decreases and the ratio of resin increases, it is also considered that the strength of the cover glass 20 decreases. In consideration of this point, the maximum value of the coating size of the reinforcing portion 26 is set to 250 μm or less in the thinnest portion (the portion represented by the symbol Tmin in FIG. 5), and the thickest portion (see FIG. 5). In the portion represented by the symbol Tmax), it is preferably set to 500 μm or less.

  As an example, in the example shown in FIG. 5, the covering dimension Tmin of the reinforcing part 26 in the thinnest part is set to 100 μm, and the covering dimension Tmax of the reinforcing part 26 in the thickest part is set to 300 μm. Conceivable.

  The thickness of the cover glass 20 (that is, the thickness of the unit base material 22 and the thickness of the reinforcing portion 26) is appropriately set according to the required strength, the area of the cover glass 20, and the like. It is within range.

(Method for manufacturing cover glass)
Next, a method for manufacturing the cover glass 20 having the above configuration will be described with reference to FIGS. 6A to 7D.

  First, referring to FIGS. 6A to 6E (a) and 6 (b), a process of forming a unit laminate 35 having a unit substrate 22 and protective films 81 and 82 using a substrate 30 made of large tempered glass. Will be described. 6A, 6B (a), FIG. 6C, FIG. 6D (a), and FIG. 6E (a) are cross-sectional views showing the substrate 30 in this step. FIG. 6E (b) is an enlarged cross-sectional view of the unit laminate body 35 shown in FIG. 6E (a). 6B (b) and 6D (b) are plan views showing the base material 30 in this step.

  First, as shown to FIG. 6A, the base material 30 which consists of a large tempered glass is prepared. The base material 30 includes a first surface 30a, a second surface 30b on the opposite side of the first surface 30a, and a side surface 30c extending between the first surface 30a and the second surface 30b. As shown in FIG. 6A, a compressive stress layer 24a is formed on the first surface 30a, the second surface 30b, and the side surface 30c of the base material 30, and a tensile stress layer 24b exists inside the compressive stress layer 24a. doing. Thus, the entire surface of the base material 30 is formed by the compressive stress layer 24a.

  Next, as shown to FIG. 6B (a) (b), on the 1st surface 30a of the base material 30, the 1st decorating part 60 and the touchscreen sensor part 40 are formed in a predetermined some division (element part formation) Process). For example, in FIG. 6B (b), the first surface 30a of the base material 30 is divided into two rows in the vertical direction of the paper surface and divided into three columns in the horizontal direction of the paper surface. The decoration part 60 and the touch panel sensor part 40 are formed. The number of sections of the base material 30 is not particularly limited. As a method of forming the first decorating unit 60 and the touch panel sensor unit 40 on the first surface 30a side, a known method is appropriately used, and for example, a photolithography method is used. In the following description, the touch panel sensor unit 40 and the first decoration unit 60 may be collectively referred to as an element unit 70.

  Then, the protective film formation process which provides the 1st protective film 81 and the 2nd protective film 82 in a predetermined some division on the 1st surface 30a and the 2nd surface 30b of the base material 30 is implemented. First, as shown in FIG. 6C, a first protective film 81 is provided on the first surface 30a of the substrate 30 to continuously cover the element portions 70 respectively provided in the plurality of sections. A second protective film 82 is provided on the second surface 30 b of the substrate 30. In the example shown in FIG. 6C, the first protective film 81 and the second protective film 82 are provided so as to cover the entire area of the first surface 30a and the second surface 30b of the substrate 30, respectively.

  The protective films 81 and 82 function as a resist that protects the element portion 70 when the base material 30 is divided by wet etching described later using hydrofluoric acid or the like. As long as it has the tolerance with respect to the etching liquid used in order to divide the base material 30, the material which comprises the protective films 81 and 82 is not specifically limited. For example, biaxially stretched polypropylene or unstretched polypropylene having a thickness of about 50 to 100 μm can be used as a material for forming the protective films 81 and 82. In this case, by attaching a biaxially stretched polypropylene sheet or an unstretched polypropylene sheet on the first surface 30a and the second surface 30b of the substrate 30 through an adhesive layer having a thickness of about 20 μm, the protective film 81, 82 is configured.

  Thereafter, as shown in FIGS. 6D (a) and 6 (b), the first protective film 81 and the second protective film 82 provided over the entire area of the first surface 30a and the second surface 30b are replaced with the first surface 30a and the first protective film 82. Dividing into sections of the two surfaces 30b. As a result, a gap is formed along the boundary of each partition in the first protective film 81 covering each element portion 70 and the corresponding second protective film 82.

  A specific method for dividing the first protective film 81 and the second protective film 82 is not particularly limited, and various methods can be adopted. For example, unnecessary portions (portions that become gaps) of the first protective film 81 may be removed using a mold having a shape corresponding to the shape of the first protective film 81 shown in FIG. 6D (b). Also on the second surface 30b side, by using a mold having a shape corresponding to the mold for the first protective film 81, unnecessary portions (portions that become gaps) of the second protective film 82 can be removed. In addition, unnecessary portions of the first protective film 81 and the second protective film 82 may be removed using laser processing.

  Thereafter, as shown in FIG. 6E (a), a cutting step is performed in which the base material 30 is cut along the gap between the first protective film 81 and the second protective film 82 provided in each section of the base material 30. Specifically, the base material 30 is wet-etched from the first surface 30a side and the second surface 30b side of the base material 30 by using the first protective film 81 and the second protective film 82 as resists, thereby removing the base material 30. Disconnect. As the etching solution, hydrofluoric acid or the like is used as described above. As a result, as shown in FIG. 6E (a), the unit base 22 made of glass, the element part 70 provided on the first surface 22a side of the unit base 22, and the first surface 22a of the unit base 22 The unit laminated body 35 having the first protective film 81 provided on the element portion 70 and the second protective film 82 provided on the second surface 22b of the unit base member 22 can be obtained.

  FIG. 6E (b) is an enlarged cross-sectional view of the unit laminate body 35 shown in FIG. 6E (a). As shown in FIG. 6E (b), the first protective film 81 is configured to protrude laterally from the first surface 22a of the unit base member 22. Similarly, the second protective film 82 is configured to protrude from the second surface 22 b of the unit base member 22 to the side. Such a relationship between the unit base material 22 and the first protective film 81 and the second protective film 82 is based on the fact that the first surface 22a of the unit base material 22 and the first surface 22a of the unit base material 22 and This is realized by continuing the etching process for a time that allows the unit base material 22 to be penetrated by etching from both of the two surfaces 22b. In the etching step, etching proceeds isotropically in both the depth direction and the horizontal direction at a position in the vicinity of the first surface 22a and the second surface 22b of the side surface 22c of the unit base member 22 in general. For this reason, as shown in FIG. 6E (b), in the vicinity of the first surface 22a and the second surface 22b of the side surface 22c of the unit base member 22, an intermediate portion between the first surface 22a and the second surface 22b is provided. In comparison, the etching proceeds deeper. As a result, the first side surface 22d that intersects the end portion 22ae and expands outward as it goes to the second surface 22b side, and the second side surface 22e that intersects the end portion 22be and extends outward toward the first surface 22a side, can get.

  Next, with reference to FIGS. 7A to 7D, a process for obtaining the cover glass 20 whose side surfaces are reinforced by providing reinforcing portions (resin etc.) on the side surfaces 22 c of the unit base material 22 of the unit laminate 35. explain.

First, as shown in FIG. 7A, an application step of applying an application liquid 27 containing a curable material such as an ultraviolet curable resin or a thermosetting resin onto the side surface 22c of the unit base material 22 is performed. Here, the case where the coating liquid containing acrylic resin and a photoinitiator is used is demonstrated.
In the coating process, the coating liquid 27 is filled in a space surrounded by the side surface 22c of the unit base member 22, the first protective film 81, and the second protective film 82, as shown in FIG. 7A. As shown in FIG. 7A, the coating liquid 27 may be applied to the extent that it overflows also onto the end surface 81c of the first protective film 81 and the end surface 82c of the second protective film 82.

  Next, the coating liquid 27 overflowing on the end surface 81c of the first protective film 81 and the end surface 82c of the second protective film 82 is scraped off using a squeegee or the like. As a result, as shown in FIG. 7B, the surface of the coating liquid 27 coincides with the end surface 81 c of the first protective film 81 and the end surface 82 c of the second protective film 82.

  Then, the hardening process which hardens the coating liquid 27 provided on the side surface 22c of the unit base material 22 is implemented. Here, the coating liquid 27 is cured by irradiating the coating liquid 27 with light such as ultraviolet rays. Thereby, the reinforcing part 26 is formed on the side surface 22 c of the unit base material 22.

  Next, the first protective film 81 on the first surface 22a of the unit base 22 and the second protective film 82 on the second surface 22b of the unit base 22 are removed. As a result, as shown in FIG. 7C, a cover glass 20 including the unit base material 22 and the reinforcing portion 26 provided on the side surface 22c of the unit base material 22 can be obtained. Thereafter, as shown in FIG. 7D, the second decorative portion 62 is placed at a position on the first surface 22 a side of the unit base member 22 or the first surface 26 a side of the reinforcing portion 26 and outside the first decorative portion 60. It may be provided. The 2nd decorating part 62 is comprised so that the 1st decorating part 60 and the same color may be exhibited, for example. By further providing such a second decorative portion 62, the range of the non-active area Aa2 that can exhibit a desired color is expanded to the outside, and design improvements such as prevention of light leakage from the outer peripheral portion are improved. Can be planned. Moreover, it is preferable that the 2nd decorating part 62 is comprised so that it may overlap with the reinforcement part 26, when it sees along the normal line direction of the 1st surface 20a of the cover glass 20. FIG.

  According to the present embodiment, the reinforcing portion 26 made of a curable resin is provided on the side surface 22 c of the unit base material 22. For this reason, when an impact is applied to the side surface 20 c of the cover glass 20, the force transmitted to the side surface 22 c of the unit base material 22 is alleviated by the reinforcing portion 26, and damage such as cracks occurs on the side surface 22 c of the unit base material 22. This can be suppressed. Thereby, even if the compressive stress layer is not formed on the side surface 22c of the unit base member 22, the impact resistance of the cover glass 20 can be sufficiently increased. Further, even if the tensile stress layer 24b is exposed on the side surface 22c of the unit base member 22, the exposed tensile stress layer 24b can be covered with the reinforcing portion 26, so that the impact resistance of the cover glass 20 is increased. Sex can be made high enough.

  Moreover, according to this Embodiment, the resin material which comprises the reinforcement part 26 contains the polyene polythiol type resin. For this reason, even if it is a case where the reinforcement part 26 is exposed with respect to external environments, such as air | atmosphere, it can suppress that a polymerization reaction will be inhibited by oxygen. As a result, it is possible to obtain a reinforcing portion 26 having a desired hardness that has undergone a sufficient polymerization reaction. Moreover, it can prevent that the hardness of the reinforcement part 26 becomes high too much by using polyene-polythiol-type resin. Therefore, it is possible to obtain the reinforcing portion 26 in which the balance between hardness and toughness is kept good. Moreover, the wettability of the surface of the reinforcement part 26 can be ensured appropriately by using a polyene-polythiol resin. For this reason, the coating liquid applied on the first surface 26a of the reinforcing part 26 after the reinforcing part 26 is formed, for example, the coating liquid for the second decorating part 62 remains stably on the first surface 26a. Can do. That is, the printability of the first surface 26a of the reinforcing portion 26 can be sufficiently ensured. This makes it possible to uniformly form components such as the second decorative portion 62 on the first surface 26 a of the reinforcing portion 26.

  Moreover, in this Embodiment, the reinforcement part 26 is laterally protruded from the 1st protective film 81 and the 2nd surface 22b of the unit base material 22 which protruded from the 1st surface 22a of the unit base material 22 as mentioned above. It is formed in a space positioned by the protruding second protective film 82. For this reason, as shown to FIG. 7C and FIG. 7D, the 1st surface 22a of the unit base material 22 and the 1st surface 26a of the reinforcement part 26 are located on the same plane. Similarly, the 2nd surface 22b of the unit base material 22 and the 2nd surface 26b of 26 are located on the same plane. That is, there is no or almost no step between the unit base member 22 and the reinforcing portion 26. For this reason, it can suppress that the boundary between the unit base material 22 and the reinforcement part 26 is visually recognized by an observer. Therefore, according to the reinforcement part 26 of this Embodiment, ensuring of the intensity | strength of the side surface 20c of the cover glass 20 and ensuring of the design property of the cover glass 20 can be made to make compatible. In addition, the operational feeling of the touch panel is not hindered by the steps.

In the present embodiment, as described above, in the reinforcing portion 26, the coating liquid 27 overflowing on the end surface 81c of the first protective film 81 and the end surface 82c of the second protective film 82 is used using a squeegee or the like. By scraping, the side surface 26c of the reinforcing portion 26 is leveled. For this reason, in the reinforcing part 26 obtained by curing the coating liquid 27, the position of the end part 26ae of the first surface 26a coincides with the position of the end face 81c of the first protective film 81. Similarly, the position of the end portion 26be of the second surface 26b of the reinforcing portion 26 matches the position of the end surface 82c of the second protective film 82. Thus, according to the present embodiment, the position of the end portion 26ae of the first surface 26a and the position of the end portion 26be of the second surface 26b of the reinforcing portion 26 are set to the positions of the end surfaces 81c and 82c of the protective films 81 and 82. Can be determined based on
As described above, the reinforcing portion 26 is formed based on the coating liquid 27 having a predetermined fluidity. Therefore, if the coating liquid 27 is applied without using a frame such as the protective films 81 and 82, it is difficult to precisely control the dimensions such as the thickness and shape of the coating liquid 27. On the other hand, the positions of the end faces 81c and 82c of the protective films 81 and 82 are determined with high accuracy by processing using a mold or a laser as described above. Therefore, according to the present embodiment, it is possible to realize the accuracy according to the accuracy in the processing using a mold or a laser as the accuracy of the dimensions such as the thickness and shape of the coating liquid 27. For this reason, according to this Embodiment, the position of edge part 26ae, 26be of the reinforcement part 26, ie, the position of the edge part of the cover glass 20, can be defined with a sufficient precision. Thereby, when the cover glass 20, the display device 15, and the case are assembled, the ease of the process and the yield can be increased. Moreover, when the 1st decorating part 60 and the touchscreen sensor part 40 are provided in the cover glass 20 like this Embodiment, the process precision of the 1st decorating part 60 with respect to the display apparatus 15 and the touchscreen sensor part 40 is also improved. be able to. Thereby, the high designability and operativity of the display apparatus 10 with a cover glass are realizable.

  Further, when the side surface 26c of the reinforcing portion 26 is configured as a flat surface that extends substantially flat between the end portion 26ae and the end portion 26be, not only the position of the end portions 26ae and 26be of the reinforcing portion 26 but also the reinforcing portion. The position of the entire side surface 26c of the 26 is also determined according to the positions of the end surfaces 81c and 82c of the protective films 81 and 82. That is, the processing accuracy of the entire side surface 20c of the cover glass 20 as well as the end portion of the cover glass 20 can be increased.

  Moreover, according to this Embodiment, since the side surface 20c of the cover glass 20 is comprised by the reinforcement part 26 which consists of resin, compared with the case where the side surface 20c of the cover glass 20 is comprised with glass, it is a cover. The edge portion of the side surface 20c of the glass 20 does not need to be subjected to laceration prevention processing by chamfering or the like.

In addition, the reinforcement part 26 of the cover glass 20 may be comprised so that the 1st decoration part 60 provided in the 1st surface 20a side of the cover glass 20 and the 2nd decoration part 62 may be exhibited. For example, the reinforcing portion 26 may include a color pigment having the same color as the color pigment included in the first decorative portion 60 and the second decorative portion 62. In this case, the area around the outer edge of the non-active area Aa2 is visually recognized as an area having the same color as the areas of the first decorative portion 60 and the second decorative portion 62 located on the inner side. For this reason, the effect on the design similar to the case where the 1st decorating part 60 and the 2nd decorating part 62 are extended to the outer edge of inactive area Aa2 can be acquired.
Generally, the 1st decoration part 60 and the 2nd decoration part 62 are formed by apply | coating the coating liquid containing a resin material and a pigment on the cover glass 20 (on the unit base material 22 or the reinforcement part 26). On the other hand, it is not easy to accurately apply the coating liquid to a region around the outer edge of the inactive area Aa2.
Here, when the reinforcement part 26 is colored as described above, the first decorative part 60 and the second decorative part 62 are not provided in the region around the outer edge of the inactive area Aa2, and thus the inactive area Aa2 is provided. A region around the outer edge of the image is visually recognized with a desired color. For this reason, the process of providing the 1st decorating part 60 and the 2nd decorating part 62 can be made easier.

The “same color” means that the chromaticities of the two colors are close enough that the difference in color cannot be discerned with the naked eye. More specifically, “same color” means that the color difference ΔE ^* _ab between the two colors is 10 or less, preferably 3 or less. The “different color” means that the color difference ΔE ^* _ab between the two colors is larger than 10. Here, the color difference ΔE ^* _ab is a value calculated based on L ^* , a ^* and b ^* in the L ^* a ^* b ^* color system, and is an index relating to a color difference when observed with the naked eye. Is the value.

  Note that various modifications can be made to the above-described embodiment. Hereinafter, some modifications will be described with reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above embodiment are used for the parts that can be configured in the same manner as in the above embodiment. A duplicate description is omitted. In addition, when it is clear that the operational effects obtained in the above-described embodiment can be obtained in the modified example, the description thereof may be omitted.

(First modification)
In the above-described embodiment, the element part forming step of forming the element part 70 such as the first decoration part 60 and the touch panel sensor part 40 on the first surface 30 a of the base material 30 is performed on the base material 30. The example implemented prior to the protective film formation process which provides the protective film 81 and the 2nd protective film 82 was shown. However, the present invention is not limited to this, and a step of providing the first protective film 81 and the second protective film 82 on the base material 30 in a state where the element portion 70 is not provided, and then cutting the base material 30 and You may implement the process of providing the reinforcement part 26 on the side surface 22c of the unit base material 22. FIG. As a result, as shown in FIG. 8, it is possible to obtain the cover glass 20 including the unit base material 22 and the reinforcing portion 26 provided on the side surface 22 c of the unit base material 22.

  In the present modification shown in FIG. 8, the reinforcing portion 26 may be configured to exhibit a predetermined color. For example, the reinforcing part 26 may include a color pigment exhibiting a predetermined color. In this case, it is possible to realize an improvement in design properties such as prevention of light leakage from the outer peripheral portion without providing the first decorative portion 60 and the second decorative portion 62. Although not shown, in the present modification shown in FIG. 8, the cover glass 20 may further include a decorating portion provided on the first surface 26 a of the reinforcing portion 26 after the reinforcing portion 26 is formed.

(Second modification)
In the first modified example described above, the first protective film 81 and the second protective film 82 are provided for the base material 30 in a state where neither the first decoration unit 60 nor the touch panel sensor unit 40 is provided. An example is shown. However, the present invention is not limited to this, and the first protective film 81 and the second protective film 82 with respect to the base material 30 in a state where the touch panel sensor unit 40 is not provided but the first decoration unit 60 is provided. Then, the step of cutting the base material 30 and the step of providing the reinforcing portion 26 on the side surface 22c of the unit base material 22 may be performed. Accordingly, as shown in FIG. 9, the unit base material 22, the first decorating part 60 provided on the first surface 22 a of the unit base material 22, and the side surface 22 c of the unit base material 22 are provided. The cover glass 20 provided with the reinforcement part 26 can be obtained. As shown in FIG. 9, the cover glass 20 may further include a second decorating part 62 provided at a position outside the first decorating part 60 after the reinforcing part 26 is formed.

(Third Modification)
After obtaining the reinforcing portion 26 by curing the coating liquid 27, the shape of the side surface 26c, that is, the shape of the side surface 20c of the cover glass 20 may be adjusted by processing the side surface 26c of the reinforcing portion 26. Since the reinforcement part 26 is comprised with the resin material as mentioned above, compared with the case where the side surface 20c of the cover glass 20 is comprised with the tempered glass, the side surface 20c of the cover glass 20 is processed, and a desired shape is formed. It is easier to get. In addition, strength reduction and microcracks are less likely to occur due to processing. As a processing method, for example, processing using a polishing machine can be employed.

  For example, as shown in FIG. 10, the side surface 26c of the reinforcing portion 26 may be processed so that both the end portion 26ae on the first surface 26a side and the end portion 26be on the second surface 26b side of the reinforcing portion 26 are scraped off. . In the example shown in FIG. 10, both the portion that intersects the first surface 26 a and the portion that intersects the second surface 26 b of the side surface 26 c of the reinforcing portion 26 are processed into round surfaces. Even in this case, if even a part that is not processed (unprocessed part 26d) remains on the side surface 22c, the outer shape of the cover glass 20 is increased based on the above-described coating method using the protective films 81 and 82. Dimensional accuracy can be ensured. FIG. 10 shows an example in which the side surface 26c is processed so that the side surface 26c becomes a round surface. However, the present invention is not limited to this, and although not illustrated, the side surface 26c becomes a square surface. 26c may be processed. Although not shown, one of the end portion 26ae on the first surface 26a side and the end portion 26be on the second surface 26b side of the reinforcing portion 26, for example, at least the end portion 26ae on the first surface 26a side is scraped off. The side surface 26c of the reinforcing portion 26 may be processed.

(Fourth modification)
In the above-described embodiment, the reinforcing portion 26 is formed by applying the coating liquid 27 in the space surrounded by the side surface 22c of the unit base member 22, the first protective film 81, and the second protective film 82. An example is shown, but the present invention is not limited to this. Even when the reinforcing portion 26 is formed by other methods, the resin material constituting the reinforcing portion 26 includes a polyene-polythiol-based resin, so that it has a desired hardness and toughness sufficiently undergoing a polymerization reaction. The reinforcement part 26 can be obtained. Further, the printability of the reinforcing portion 26 can be sufficiently ensured. Examples of the method for forming the reinforcing portion 26 include an injection molding method, a dispensing method, a spray coating method, a roller coating method, and a dipping method. FIG. 11 is a cross-sectional view showing an example of the cover glass 20 provided with the reinforcing portion 26 formed by the dipping method.

(Fifth modification)
In the present embodiment described above, the side surface 22c intersects the end portion 22ae of the first surface 22a of the unit base member 22, and the first side surface 22d that spreads outward toward the second surface 22b side of the unit base member 22. And the second surface 22e that intersects with the end 22be of the second surface 22b of the unit base member 22 and expands outward as it goes to the first surface 22a side of the unit base member 22 is shown. However, the shape of the side surface 22c is not particularly limited as long as the reinforcing portion 26 can be provided. For example, as shown in FIG. 12, the side surface 22c may extend so as to be orthogonal to the first surface 22a and the second surface 22b. The side surface 22c having such a shape can be formed, for example, by cutting the substrate 30 using a laser. Further, by forming a scribe line on the surface of the base material 30 using a cutter or a laser, and then applying a striking force or a bending stress to the base material 30, the base material 30 is cut from the scribe line as a starting point. Alternatively, the side surface 22c shown in FIG. 12 may be formed.

(Sixth Modification)
In the above-described embodiment, the example in which the tensile stress layer 24b is exposed on the side surface 22c of the unit base material 22 is shown. However, the present invention is not limited to this, and as shown in FIG. 13, the compressive stress layer 24 a may be formed not only on the first surface 22 a and the second surface 22 b of the unit base member 22 but also on the side surface 22 c. Even in this case, the force transmitted to the side surface 22c of the unit base material 22 when the impact is applied to the side surface 20c of the cover glass 20 is reduced by providing the reinforcing portion 26 on the side surface 22c of the unit base material 22. can do.

  In the fifth and sixth modified examples described above, the method for forming the reinforcing portion 26 on the side surface 22c is not particularly limited, and the methods described in the present embodiment and the modified examples are appropriately adopted. The In addition, when forming the reinforcement part 26 by apply | coating the coating liquid 27 using the 1st protective film 81 and the 2nd protective film 82, the 1st protective film 81 and the 2nd protective film 82 cut | disconnect the base material 30. Then, after the unit base material 22 is obtained, the unit base material 22 may be provided on the first surface 22a and the second surface 22b.

(Seventh Modification)
In the above-mentioned embodiment and each modification, the example in which the reinforcement part 26 was formed on the side surface 22c which comprises the external shape of the unit base material 22 among the side surfaces of the unit base material 22 was shown. However, the present invention is not limited to this, and when the through hole 23 is formed in the unit base member 22 as shown in FIG. 14, the reinforcing portion 26 may be provided on the wall surface 23 a of the through hole 23. That is, in the present application, the “side surface of the unit base material 22” is a concept including the wall surface 23 a of the through hole 23 formed in the unit base material 22. The through hole 23 is provided, for example, for mounting a camera, a speaker, or the like on the display device.

  FIG. 15 is a cross-sectional view showing a step of forming the reinforcing portion 26 on the wall surface 23a of the through hole 23 shown in FIG. FIG. 15 shows a state in which the reinforcing portion 26 is formed not only on the wall surface 23 a of the through hole 23 but also on the side surface 22 c constituting the outer shape of the unit base material 22. In the example shown in FIG. 15, the first protective film 81 and the second protective film 82 are provided so as to protrude inward from the wall surface 23 a of the through hole 23 of the unit base material 22. Therefore, by applying the coating liquid 27 in the space surrounded by the wall surface 23a of the through hole 23 of the unit base member 22, the first protective film 81, and the second protective film 82, as shown in FIG. The reinforcing portion 26 can be formed on the wall surface 23a with dimensional accuracy.

  Also in this modification, the reinforcement part 26 provided on the wall surface 23a of the through-hole 23 of the unit base material 22 contains polyene-polythiol resin. For this reason, the reinforcing part 26 having a desired hardness that has undergone a sufficient polymerization reaction can be provided on the wall surface 23 a of the through hole 23. Further, the printability of the reinforcing portion 26 can be sufficiently ensured.

(Other variations)
In the above-described embodiment, the example in which the reinforcing portion 26 and the coating solution 27 include a curable resin that cures by heating or ultraviolet irradiation and is cured by the polymerization reaction is shown. However, the present invention is not limited thereto. There is nothing. When coated on the side surface 22c of the unit base member 22, it has a predetermined fluidity, but various fluids can be used as the coating liquid 27 for forming the reinforcing portion 26 as long as it can be cured thereafter. Can be used. For example, a fluid made of a resin material melted by heat may be used as the coating liquid 27. In this case, after the coating liquid 27 is applied onto the side surface 22c of the unit base member 22, the coating liquid 27 is hardened by being cooled and solidified. Thereby, the reinforcement part 26 containing a resin material can be obtained. Thus, in this embodiment, “curing” is a concept including not only a phenomenon in which the resin material is cured by heating or ultraviolet irradiation, but also a phenomenon in which the resin material is cured by being cooled and solidified. The resin material may be cooled and solidified by natural cooling, or the resin material may be cooled and solidified by forced cooling. “Solidification” means that the substance changes from a gas or liquid state to a solid state.

  In addition, although some modified examples with respect to the above-described embodiment have been described, naturally, a plurality of modified examples can be applied in combination as appropriate.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to description of a following example, unless the summary is exceeded.

Example 1
The reinforcing portion 26 was formed on the side surface 22c of the unit base material 22 using the method shown in FIGS. 7A to 7D described above. As a material for constituting the reinforcing portion 26, three types of acrylic resin, epoxy resin, and polyene-polythiol resin were used. UV-3300 manufactured by Toagosei Co., Ltd. was used as the acrylic resin. As the epoxy resin, TB3114 manufactured by ThreeBond Co., Ltd. was used. As the polyene-polythiol-based resin, Photolek A-784 manufactured by Sekisui Chemical Co., Ltd. was used.

  First, three unit base materials 22 provided with the first protective film 81 and the second protective film 82 were prepared. As the unit base material 22, a surface of 0.7 mm thick aluminosilicate glass provided with a 24 μm thick compressive stress layer by chemical strengthening was used. Next, as shown in FIG. 7A described above, the coating liquid 27 containing any one of the above-described three types of resins was applied to the side surface 22c of the unit base material 22, respectively. Thereafter, the coating liquid 27 was cured by irradiating light to the coating liquid 27, thereby obtaining the reinforcing portion 26. As the viscosity of the coating liquid 27 and the conditions for curing the coating liquid 27, the conditions recommended by the material manufacturer that provides the resin material contained in the coating liquid 27 were adopted.

  The side surface 26c of the obtained reinforcement part 26 was touched by hand, and it was evaluated whether it felt sticky. As a result, no stickiness was felt with respect to the reinforcing portion 26 composed of the epoxy resin and the polyene-polythiol resin. On the other hand, stickiness was felt with respect to the reinforcing portion 26 made of acrylic resin.

  The side surface 26c of the reinforcing portion 26 is a portion that is exposed to an external environment such as the atmosphere when cured. Therefore, when the acrylic resin is used, it is considered that the polymerization reaction is inhibited by oxygen, and as a result, the side surface 26c of the reinforcing portion 26 remains uncured. On the other hand, the degree to which the polymerization reaction of the polyene-polythiol resin is inhibited by oxygen is smaller than that of the acrylic resin. For this reason, in the reinforcement part 26 comprised from polyene-polythiol type-resin, it is thought that the side surface 26c was able to be prevented from sticking.

(Example 2)
The printability of the above-mentioned three types of resins used in Example 1 was evaluated. Specifically, first, a glass plate 90 was prepared as shown in FIG. Next, as shown in FIG. 16 (b), a coating liquid containing any of the above-mentioned three types of resins is applied onto the glass plate 90, and then the coating liquid is cured, thereby causing the glass plate 90 to be cured. A resin layer 91 was formed. Next, as shown in FIG. 16C, printing patterns 92 a to 92 f are provided on the resin layer 91 by printing a plurality of types of ink set to have different surface tensions on the resin layer 91. . Here, the printing patterns 92a to 92f are respectively composed of ink having a surface tension of 32, 34, 36, 38, 40, and 42 mN / m. As a means for printing such an ink on the resin layer 91, a set of # 32, 34, 36, 38, 40, 42 of “JUMBO SURFACE TENSION TEST PENS” manufactured by Corona Supplies Ltd. was used. The number after # represents the surface tension (unit: mN / m) of the ink contained in the pen.

  Then, after waiting for one hour to pass, the state of the printing patterns 92a-92f was observed. FIG. 16D shows an example of the state of the print patterns 92a to 92f after one hour has elapsed. In general, when the surface tension is higher, the ink is repelled from the base (here, the resin layer 91), and as a result, the printing pattern is likely to be disturbed. That is, in the print patterns 92a to 92f shown in FIG. 16, the pattern located on the right side, that is, the pattern on the print pattern 92f side, is repelled from the resin layer 91 and is easily disturbed. Therefore, when the printability of the resin layer 91 is insufficient, the pattern on the left side is not disturbed with any one of the print patterns 92a to 92f as a boundary, and the pattern on the right side is more than that. Will be disturbed. In the example shown in FIG. 16D, the resin layer 91 has printability with respect to the print patterns 92a to 92d (pattern having a surface tension of 32 to 38 mN / m), but the print patterns 92e and 92f (surface tension). Is 40, 42 mN / m pattern). By performing such a test, it is possible to evaluate the printability of the above-described three types of resins for inks having surface tensions of 32, 34, 36, 38, 40, and 42 mN / m.

Table 1 shows the evaluation results of printability. In Table 1, “◯” means that the printing pattern made of ink was not disturbed (ink repelling), and “x” means that ink repelling occurred. As shown in Table 1, the resin layer 91 composed of an acrylic resin and a polyene-polythiol resin had printability for ink having a surface tension of 32 to 42 mN / m. On the other hand, the resin layer 91 composed of an epoxy resin has printability for ink having a surface tension of 32 mN / m, but has printability for ink having a surface tension of 34 to 42 mN / m. It wasn't.

  As described above, the polyene-polythiol-based resin suppresses that the coating liquid is repelled and the pattern is disturbed even when the surface tension of the coating liquid such as ink applied thereon is large. Can do. Therefore, when components, such as the 2nd decoration part 62, are provided on the 1st surface 26a of the reinforcement part 26, it can be said that it is preferable to comprise the reinforcement part 26 using polyene-polythiol type resin.

  As an additional evaluation, when ink was printed on a layer made of an epoxy resin by a screen printing method, defective printing due to the ink being repelled by the epoxy resin was confirmed. As the ink, 1690N manufactured by Seiko Advance was used.

(Example 3)
The impact resistance of epoxy resins and polyene-polythiol resins was evaluated. Specifically, first, in the same manner as in Example 1, cover glasses 20 each having a reinforcing portion 26 made of an epoxy resin and a polyene-polythiol resin were produced. For comparison, a cover glass 20 without the reinforcing portion 26 was produced. Next, as shown in FIG. 17, impact was applied to the side surface 20 c of the cover glass 20 using the striking means 94. When the reinforcing portion 26 is provided, the side surface 20 c of the cover glass 20 is configured by the side surface 26 c of the reinforcing portion 26.

  As the hitting means 94, a round bar having a predetermined diameter made of stainless steel (SUS) having a length of 35 cm was used. Here, tests were performed using SUS round bars having diameters of 0.50, 0, 75, 1.00, and 1.25 cm, respectively. Hereinafter, a specific test method will be described.

  First, the cover glass 20 and the striking means 94 supported by the support means 95 are placed on the placing table 97. The cover glass 20 is placed so that the side surface 20c faces upward. The support means 95 rotates the striking means 94 over 90 ° about the other end 94b until the one end 94a of the striking means 94 changes from a state in which the one end 94a faces directly upward to a state in which the one end 94a of the striking means 94 is rotated. The other end 94b of the striking means 94 is supported so as to collide with the side surface 20c of the cover glass 20. In this case, collision energy determined by the length and diameter of the striking means 94 can be accurately applied to the side surface 20 c of the cover glass 20. In addition, the 1st surface 20a and the 2nd surface 20b of the cover glass 20 are hold | maintained in the circumference | surroundings of the cover glass 20, and it hold | maintains to prevent that the cover glass 20 falls down when an impact is applied to the cover glass 20 Means 96 may be provided.

  After impact was applied to the side surface 20c of the cover glass 20 using the striking means 94, a four-point bending test was performed to measure the bending strength of the cover glass 20.

The evaluation results of impact resistance are shown in Table 2. In Table 2, “◯” means that the measured bending strength was 500 MPa or more, and “x” means that the measured bending strength was less than 500 MPa. As shown in Table 2, in the cover glass 20 provided with the reinforcing portion 26 made of a polyene-polythiol resin, an impact is applied to the side surface 20c of the cover glass 20 using a striking means 94 having a diameter of 1.00 cm. Even after the test, sufficient bending strength could be maintained. On the other hand, in the cover glass 20 provided with the reinforcing portion 26 made of epoxy resin, a sufficient bending strength is obtained after impact is applied to the side surface 20c of the cover glass 20 using the hitting means 94 of 1.00 cm. Could not be maintained.

  As described above, the hardness of the epoxy resin is excessively high as the hardness of the material for constituting the reinforcing portion 26 of the cover glass 20 and is therefore brittle. For this reason, when an impact is applied to the side surface 20c of the cover glass 20 using the striking means 94, the reinforcing portion 26 is at least partially broken, and as a result, sufficient bending strength of the cover glass 20 can be maintained. It is thought that it was not possible. On the other hand, the hardness of the polyene-polythiol-based resin is within an appropriate range, for example, within the range of D50 to D75 as described above. For this reason, the reinforcement part 26 comprised from polyene-polythiol-type resin can absorb the impact applied from the striking means 94 by elastically deforming. For this reason, it is thought that sufficient bending strength of the cover glass 20 could be maintained even after the impact was applied.

Example 4
The above three types of resins used in Example 1 were evaluated for moisture resistance. Specifically, first, in the same manner as in Example 1, the cover glasses 20 each including the reinforcing portion 26 made of the above-described three types of resins were produced. Next, each cover glass 20 was placed in a high temperature and high humidity environment at a temperature of 85 ° C. and a relative humidity of 85% for 240 hours. Thereafter, whether or not a change such as discoloration occurred in the appearance of each cover glass 20 was visually evaluated. Further, whether or not the reinforcing portion 26 is sufficiently in close contact with the side surface 22c of the unit base member 22 can be determined by holding the reinforcing portion 26 by hand, or the striking means used in the above-described fourth embodiment with respect to the reinforcing portion 26. Evaluation was performed by applying an impact using 94. As a result, it was confirmed that the appearance of the reinforcing portion 26 and the adhesion of the reinforcing portion 26 were sufficiently maintained for any of the cover glasses 20 provided with the reinforcing portion 26 made of three types of resins.

(Example 5)
The light resistance of the above-mentioned three types of resins used in Example 1 was evaluated. Specifically, first, in the same manner as in Example 1, the cover glasses 20 each including the reinforcing portion 26 made of the above-described three types of resins were produced. Next, each cover glass 20 was irradiated with light using SUNTEST CPS + manufactured by Atlas Material Testing Technology. Thereafter, whether or not a change such as discoloration occurred in the appearance of each cover glass 20 was visually evaluated. Further, whether or not the reinforcing portion 26 is sufficiently in close contact with the side surface 22c of the unit base member 22 can be determined by holding the reinforcing portion 26 by hand, or the striking means used in the above-described fourth embodiment with respect to the reinforcing portion 26. Evaluation was performed by applying an impact using 94. As a result, it was confirmed that the appearance of the reinforcing portion 26 and the adhesion of the reinforcing portion 26 were sufficiently maintained for any of the cover glasses 20 provided with the reinforcing portion 26 made of three types of resins.

DESCRIPTION OF SYMBOLS 10 Display apparatus with cover glass 15 Display apparatus 20 Cover glass 22 Unit base material 24a Compressive stress layer 24b Tensile stress layer 26 Reinforcement part 27 Coating liquid 30 Base material 40 Touch panel sensor part 60 1st decoration part 62 2nd decoration part

Claims (4)

A cover glass provided in the display device,
A first substrate, a second substrate opposite to the first surface, and a side surface extending between the first surface and the second surface, and a unit substrate made of glass;
Provided on a side surface of the unit base material, and a reinforcing portion including a resin material,
The cover glass in which the resin material of the reinforcing portion has a polyene-polythiol-based photocurable resin containing an ene compound and a thiol compound.   The cover glass according to claim 1, wherein a decorative portion exhibiting a predetermined color is provided at least partially on the surface of the reinforcing portion.   The cover glass according to claim 1 or 2, wherein the polyene-polythiol-based photocurable resin of the resin material of the reinforcing portion includes 20 to 80 wt% of an ene compound and 20 to 80 wt% of a thiol compound. . A display device;
A cover glass disposed on the display device,
A display device with a cover glass, wherein the cover glass is made of the cover glass according to any one of claims 1 to 3.