JP6183706B2 - Cover glass and display device with cover glass - Google Patents

Description

  The present invention relates to a cover glass provided on an observer side of 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 at least a part of a side surface of a cover glass is covered with a polymer coating.

JP 2012-88946 A Special table 2012-527399 gazette

  If the hardness of the coating provided on the side surface of the cover glass is too high, the impact applied to the coating is transmitted as it is to the side surface of the cover glass, which may damage the side surface of the cover glass. Therefore, in order to disperse and / or absorb an impact by the coating and thereby prevent a large stress from being transmitted to the side surface of the cover glass, it is preferable that the coating has a certain degree of flexibility. However, when the flexibility of the coating is too high, the coating is plastically deformed when an impact force is applied, and the coating size of the coating on the side surface of the cover glass of the reinforcing portion becomes smaller than the original, and as a result, It is considered that the function of dispersing and / or absorbing the impact may be deteriorated. In this case, the durability of the cover glass deteriorates every time an impact is applied.

  The present invention has been made in consideration of such points, and provides a cover glass and a display device with a cover glass that can maintain durability even when an impact force is applied multiple times. For the purpose.

  The present invention is a cover glass provided on the viewer side of the display device, the first surface facing the display device side, the second surface opposite to the first surface, and the first surface and the second surface. A unit base material made of glass including a side surface extending between the surface and a reinforcing part made of a resin material provided on the side surface of the unit base material, wherein the unit is made of the reinforcing part using an indenter. The elastic deformation amount of the reinforcing portion with respect to the maximum deformation amount of the reinforcing portion when being pushed toward the base material so that the ratio of the maximum deformation amount of the reinforcing portion to the covering dimension of the reinforcing portion is 0.3. A cover glass having a ratio of 0.9 or more.

  In the cover glass according to the present invention, preferably, a ratio of the elastic deformation amount of the reinforcing portion to the maximum deformation amount of the reinforcing portion is 0.98 or less.

In the cover glass according to the present invention, preferably, the universal hardness of the reinforcing portion is in a range of 300 to 750 N / mm ² .

  In the cover glass according to the present invention, preferably, the reinforcing portion has the covering dimension of the reinforcing portion over a portion of at least 90% of the elastic deformation amount from a state where the deformation amount of the reinforcing portion is the maximum deformation amount. The time required for the recovery is configured to be 30 seconds or less.

  The cover glass by this invention WHEREIN: The resin material which comprises the said reinforcement part may contain urethane type resin. In this case, preferably, the covering dimension of the reinforcing portion is 100 μm or more.

  In the cover glass according to the present invention, the unit base material includes at least the compressive stress layer formed on the first surface and the second surface, the compressive stress layer on the first surface side, and the second surface side. A tensile stress layer positioned between the compressive stress layer and the tensile stress layer may be exposed on the side surface of the unit base material.

  The cover glass by this invention WHEREIN: On the said 1st surface of the said unit base material, the decorating part which exhibits a predetermined color may be provided.

  The cover glass by this invention WHEREIN: The said decoration part may be comprised so that it may overlap with the said reinforcement part, when it sees along the normal line direction of the said cover glass.

  In the cover glass according to the present invention, at least a part of the touch panel sensor unit may be provided on the first surface of the unit base material.

  In the cover glass according to the present invention, the reinforcing portion includes a first surface extending laterally from an end of the first surface of the unit base material on the same plane as the first surface of the unit base material, and You may include the 2nd surface extended to the side from the edge part of the said 2nd surface of the said unit base material on the same plane as the said 2nd surface of a unit base material.

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

  ADVANTAGE OF THE INVENTION According to this invention, even if it is a case where an impact is applied in multiple times, the cover glass which can maintain durability 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. 6 is a diagram for explaining the maximum deformation amount and the elastic deformation amount of the reinforcing portion. FIGS. 7A, 7B, and 7C are views showing a state in which the reinforcing portion is elastically restored after the reinforcing portion is pushed toward the side surface of the unit base material. FIG. 8A is a diagram showing a part of a step of forming a unit intermediate having a unit substrate and a protective film using a substrate made of large tempered glass. FIGS. 8B (a) and 8 (b) are diagrams showing a part of a step of forming a unit intermediate having a unit substrate and a protective film using a substrate made of large tempered glass. FIG. 8C is a diagram showing a part of a step of forming a unit intermediate having a unit substrate and a protective film using a substrate made of large tempered glass. FIG. 9A is a diagram illustrating a part of a process of obtaining a cover glass whose side surface is reinforced by providing a resin on a side surface of a unit base material of a unit intermediate. FIG. 9B is a diagram showing a part of a step of obtaining a cover glass whose side surface is reinforced by providing resin on the side surface of the unit base material of the unit intermediate. FIG. 10 is a cross-sectional view showing a cover glass in a first modification of the present embodiment. FIG. 11 is a cross-sectional view showing a cover glass in a second modification of the present embodiment. FIG. 12 is a cross-sectional view showing a cover glass in a third modification of the present embodiment. FIG. 13A is a cross-sectional view showing a unit intermediate in a fourth modification of the present embodiment. FIG. 13B is a cross-sectional view showing a state in which the coating liquid is applied on the side surface of the unit base material of the unit intermediate shown in FIG. 13A. FIG. 13C is a cross-sectional view showing a state in which the coating liquid overflowing from the unit intermediate shown in FIG. 13B is scraped off. FIG. 13D is a cross-sectional view showing a cover glass in a fourth modified example of the present embodiment. FIG. 14A is a diagram showing a part of a step of forming a unit intermediate having a unit base material and a protective film in a fifth modification example of the present embodiment. FIG. 14B is a diagram showing a part of a step of forming a unit intermediate having a unit base material and a protective film in the fifth modification example of the present embodiment. FIG. 14C is a diagram showing a part of a step of forming a unit intermediate having a unit base material and a protective film in the fifth modification example of the present embodiment. FIG. 15A is a diagram showing a part of a step of forming a reinforcing portion on a side surface of a unit base material of a unit intermediate in the fifth modification example of the present embodiment. FIG. 15B is a diagram showing a part of a step of forming a reinforcing portion on a side surface of a unit base material of a unit intermediate in the fifth modification example of the present embodiment. FIG. 15C is a diagram showing a part of a step of forming a reinforcing portion on a side surface of a unit base material of a unit intermediate in the fifth modification example of the present embodiment. FIG. 16 is a diagram showing an example of a cover glass that can be manufactured by the process shown in the fifth modification of the present embodiment. FIG. 17 is a view showing a measuring instrument used for measuring the bending strength of the cover glass.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 9B. 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 not only to protect the display device 15 but also to perform 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. The inactive area Aa2 on the first surface 20a of the cover glass 20 is further provided with a decorating part 60 for exhibiting a desired color.

(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 decorating unit 60 is omitted for convenience of explanation. The touch panel sensor unit 40 shown in FIG. 2 is configured as a projection-type capacitive coupling method, and detects a contact position (also referred to as a touch position) of an external conductor (for example, a human finger) to the touch panel sensor unit 40. It is configured to be possible.

  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. The first sensor electrode 41 may include a first line portion 41a that extends linearly along the first direction D1, and a first bulge portion 41b that bulges from the first line portion 41a. Similarly, the 2nd sensor electrode 42 may have the 2nd line part 42a extended along the 2nd direction D2, and the 2nd bulge part 42b bulged from the 2nd line part 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 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.

  As shown in FIGS. 3 and 4, the first line portion 41 a and the second line portion 42 a are formed so as to partially overlap each other when viewed from the normal direction of the cover glass 20. In this case, by interposing the insulating layer 47 between the first line portion 41a and the second line portion 42a, conduction between the first line portion 41a and the second line portion 42a can be prevented. . Although not shown, the insulating layer 47 is provided not only between the first line portion 41a and the second line portion 42a but also on the first bulge portion 41b and the second bulge portion 42b. Also good.

  As long as the 2nd line part 42a has electroconductivity, the material which comprises the 2nd line part 42a is not specifically limited. For example, the second line portion 42a may be made of a transparent conductive material such as indium tin oxide (ITO) like the first line portion 41a, the first bulge portion 41b, and the second bulge portion 42b. Alternatively, it may be made of an impermeable conductive material such as a silver alloy or copper. In the present embodiment, an example in which the second line portion 42 a is configured by the metal layer 52 that is also included in the lead-out wiring 43 and the terminal portion 44 will be described.

  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, in the inactive area Aa <b> 2, the decorating part 60 is arranged so as to be positioned closer to the viewer than the above-described extraction wiring 43. In this case, the decoration part 60 is visually recognized through the cover glass 20 from the user who exists in 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 decorating unit 60 and its peripheral components.

  The color of the decoration 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 decoration part 60. Although the material which comprises the decorating part 60 is determined according to the selected color, for example, when white is calculated | required, the decorating part 60 is comprised from the resin material in which coloring pigments, such as a titanium oxide, were disperse | distributed. The

  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 material 22 is made of glass, and the reinforcing portion 26 is made of a resin material. 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 high durability with respect to an impact. As a material constituting the unit base member 22, for example, aluminosilicate glass can be used.

  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 can play a role of protecting the side surface 22c of the unit base material 22 as described above.

  Although the thickness of the unit base material 22 is appropriately set according to the required strength, the area of the cover glass 20, and the like, it is within a range of, for example, 0.1 mm to 1 mm. Moreover, although the thickness of the compressive stress layer 24a of the unit base material 22 is appropriately set according to the required strength, the cutting property required when cutting the base material 30 described later, etc., for example, 10 to 50 μm It is within range.

  Next, the reinforcement part 26 is demonstrated with reference to FIG. FIG. 5 is an enlarged cross-sectional view of the side surface 20c of the cover glass 20 of FIG.

  As shown in FIG. 5, the reinforcing portion 26 includes a side surface 26 c that overlaps the side surface 22 c when viewed along the normal direction of the side surface 22 c of the unit base material 22. In addition, the reinforcing portion 26 has a first surface 26a that extends in the same plane as the first surface 22a of the unit base member 22 from the end 22ae of the first surface 22a and / or a second surface of the unit base member 22. A second surface 26b may be included that extends laterally from the end 22be of the second surface 22b on the same plane as 22b. When the reinforcing portion 26 includes the first surface 26 a and the second surface 26 b, there is no or almost no step between the unit base material 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, ensuring of the strength of the side surface 20c of the cover glass 20 by the reinforcing portion 26 and ensuring of the design property of the cover glass 20 can be achieved at the same time. In addition, the operational feeling of the touch panel is not hindered by the steps.

  FIG. 5 shows an example in which the side surface 22c of the unit base member 22 is configured as a flat surface that extends substantially flat between the first surface 22a and the second surface 22b. However, the shape of the side surface 22c is not limited to a flat surface. For example, the side surface 22c may be a curved surface. Further, the side surface 22c may be configured as a combination of a plurality of surfaces extending in various directions. In this case, the “normal direction of the side surface 22c” may be defined as a normal direction of a virtual plane orthogonal to at least one of the first surface 22a or the second surface 22b.

In FIG. 5, the covering dimension (initial covering dimension) of the reinforcing portion 26 provided on the side surface 22 c of the unit base member 22 is represented by a symbol T ₀ . The covering dimension T ₀ 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. For example, the covering dimension T ₀ of the reinforcing portion 26 is set to 100 μm or more. On the other hand, if the covering dimension T ₀ 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 reduces and the ratio of resin increases, it is also considered that the intensity | strength of the cover glass 20 falls. Considering this point, the covering dimension T ₀ of the reinforcing portion 26 is set to 500 μm or less, for example.

  Next, the characteristic of the reinforcement part 26 regarding a deformation | transformation and the resin material which comprises the reinforcement part 26 are demonstrated.

In the present embodiment, the reinforcing portion 26 is configured so that when the external force is removed after the reinforcing portion 26 is deformed by an external force due to an impact or the like, 90% or more of the deformation can be elastically restored. Yes. Accordingly, when an impact is applied thereafter, the reinforcing portion 26 can appropriately protect the side surface 22c of the unit base member 22. Specifically, the reinforcing portion 26 is directed to the unit base material 22 using a predetermined indenter, and the ratio of the maximum deformation amount of the reinforcing portion 26 to the initial covering dimension T ₀ of the reinforcing portion 26 is 0.00. 3 is configured such that the ratio of the elastic deformation amount of the reinforcing portion 26 to the maximum deformation amount of the reinforcing portion 26 when being pushed to 3 is 0.9 or more.

Hereinafter, with reference to FIG. 6 and FIGS. 7A to 7C, “the ratio of the maximum deformation amount of the reinforcing portion 26 to the initial covering dimension T ₀ ” and “the reinforcing portion 26 with respect to the maximum deformation amount of the reinforcing portion 26. A method of calculating the “ratio of elastic deformation amount” will be described. When the reinforcing portion 26 is pushed toward the unit base material 22 using an indenter 90 as shown in FIG. 7A, the covering dimension of the reinforcing portion 26 is deformed by drawing a hysteresis curve as shown in FIG. . In FIG. 6, the vertical axis represents the indentation load (mN) applied by the indenter 90 to the reinforcing portion 26, and the horizontal axis represents the change amount (μm) of the covering dimension of the reinforcing portion 26. In FIG. 6, the amount of compression (μm) generated when the reinforcing portion 26 is compressed by the indentation load is expressed as a positive value on the horizontal axis of FIG. 6.

In FIG. 6, O ₁ indicates that the indentation load of the indenter 90 and the deformation amount of the covering dimension of the reinforcing portion 26 are both zero. As the indentation load of the indenter 90 is increased, as shown by the curve connecting the points O ₁ and O ₂ , the amount of change in the covering dimension of the reinforcing portion 26 also increases. Thereafter, after the indentation load of the indenter 90 reaches a predetermined load, for example, X ₁ mN, the state where the indentation load is maintained at X ₁ mN is continued for a predetermined time. A point O _{3 in} FIG. 6 shows a state in which the deformation (change in covering dimension) of the reinforcing portion 26 is completed. The reference numeral T ₁ in FIG. 7 (a) represents the coating dimension in a state where deformation is completed in the reinforcement portion 26. The above-described maximum deformation amount is a change amount of the covering dimension in the reinforcing portion 26 in the state of the point O ₃ . Maximum amount of deformation, the coated dimension T ₀ of the reinforcing portion 26 of the initial (e.g., factory), is calculated by subtracting the covering dimension T ₁ of the reinforcing portion 26 in the state of point O _3. Further, the maximum value (convergence value) X ₁ mN of the indentation load is set so that the ratio of the maximum deformation amount of the reinforcing portion 26 to the initial covering dimension T ₀ is 0.9. Note that the position of the point O ₂ can be changed according to the increasing speed of the indentation load.

Thereafter, when the indentation load of the indenter 90 is decreased, the covering dimension of the reinforcing portion 26 is increased by elastic restoration as shown in FIG. 7B. When the indentation load of the indenter 90 is set to zero and a predetermined time elapses, the elastic restoration of the reinforcing portion 26 is completed. Code T ₂ in FIG. 7 (c) represents the coated size of the reinforcing portion 26 in a state where the elastic restoration of the reinforcing portion 26 is completed. A point O ₄ in FIG. 6 represents the deformation amount of the reinforcing portion 26 in a state where the elastic recovery of the reinforcing portion 26 is completed. Here, if the reinforcing portion 26 is a complete elastic body, the deformation amount of the reinforcing portion 26 at the final point O ₄ is zero, but if the reinforcing portion 26 is not a complete elastic body, the deformation amount at the point O ₄ is positive. Remains as the amount of. This amount is the amount of plastic deformation. Plastic deformation, from the coated dimension T ₀ of the initial of the reinforcing portion 26, is calculated by subtracting the covering dimension T ₂ of the reinforcing portion 26 in the state of point O _4.

As is apparent from FIG. 6, the elastic deformation amount of the reinforcing portion 26 is calculated as the maximum deformation amount of the reinforcing portion 26 minus the plastic deformation amount of the reinforcing portion 26. As described above, since the maximum deformation amount is calculated by T ₀ -T ₁ and the composition deformation amount is calculated by T ₀ -T ₂ , the elastic deformation amount is (T ₀ -T ₁ )-(T ₀ -T _2). ) = T ₂ −T ₁ .

As is clear from the above description, “the ratio of the maximum deformation amount of the reinforcing portion 26 to the initial covering dimension T ₀ ” is expressed as {(T ₀ −T ₁ ) / T ₀ }, The ratio of the elastic deformation amount of the reinforcing portion 26 to the maximum deformation amount is expressed as {(T ₂ −T ₁ ) / (T ₀ −T ₁ )}.

  According to the present embodiment, the reinforcing portion 26 is configured such that the ratio of the elastic deformation amount of the reinforcing portion 26 to the maximum deformation amount of the reinforcing portion 26 is 0.9 or more. For this reason, after external force is removed from the reinforcement part 26, the reinforcement part 26 can recover the covering dimension to 90% or more of the initial stage by elastic restoration. For this reason, the reinforcement part 26 can protect the side surface 22c of the unit base material 22 from the external force resulting from the impact applied after that etc. appropriately. In the following description, “the ratio of the elastic deformation amount of the reinforcing portion 26 to the maximum deformation amount of the reinforcing portion 26” is also referred to as “elastic restoring rate of the reinforcing portion 26”.

  Preferably, the reinforcing portion 26 is configured so that the elastic restoring rate of the reinforcing portion 26 is 0.98 or less, more preferably 0.95 or less. Accordingly, the reinforcing portion 26 can appropriately disperse and / or absorb the external force applied to the side surface 20c of the cover glass 20 by deforming itself. Accordingly, it is possible to appropriately suppress the external force from being transmitted to the side surface 22 c of the unit base material 22 by the reinforcing portion 26.

Further preferably, after the external force is removed from the reinforcing portion 26, the reinforcing portion 26 extends from the state in which the deformation amount of the reinforcing portion 26 is the maximum deformation amount to the at least 90% of the elastic deformation amount described above. The time required for recovering the coating size is 30 seconds or less. As a result, it is possible to reliably cope with the second and subsequent impacts. In FIG. 6, a point O ₄ ′ indicates a state in which “the covering dimension of the reinforcing portion 26 has been recovered over a portion of 90% of the elastic deformation amount”. The locus from point O ₃ through O ₄ ′ to point O ₄ differs from the locus shown in FIG. 6 depending on the speed at which the external force (indentation load) is removed, that is, the load reduction speed. The condition of “30 seconds or less” described above is a condition when the external force (indentation load) is removed faster than the speed at which the reinforcing portion 26 is elastically restored.

  Next, the resin material constituting the reinforcing portion 26 will be described. As the resin material constituting the reinforcing portion 26, a material having a high elastic restoring force that can satisfy the above-described characteristics related to deformation is used. For example, a UV curable resin material containing a urethane (meth) acrylate oligomer, a thermosetting resin material containing a polydimethylsiloxane copolymer, or the like can be used. These resin materials may also be called self-healing resins described in JP2011-161888. In addition, an epoxy resin or an acrylic resin can be used as a resin material constituting the reinforcing portion 26.

Preferably, the reinforcement part 26 is comprised so that the universal hardness may be in the range of 300-750 N / mm < ² >. The universal hardness is a value obtained by forming a film made of a resin material constituting the reinforcing portion 26 on a suitable glass with a film thickness of 5 μm and measuring the hardness of the film using a Vickers pyramid indenter. As the measuring instrument, for example, a hardness measuring device (Fischer Scope H-100V manufactured by Fischer Instrument Co.) can be used. By configuring the reinforcing portion 26 using a resin material having a universal hardness within the above range, it is possible to prevent the reinforcing portion 26 itself from being damaged by an external force.

(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. 8A to 9B.

  First, with reference to FIGS. 8A to 8C, a process of forming the unit intermediate 35 including the unit base material 22 in which the base material 30 is divided based on the base material 30 made of large tempered glass will be described. 8A, 8B (a), and 8C are cross-sectional views showing the base material 30 in this step. FIG. 8B (b) is a plan view showing the base material 30 in this step.

  First, as shown in FIG. 8A, a base material 30 made of 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. 8A, 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 in FIGS. 8B (a) and 8 (b), the decorative portion 60 and the touch panel sensor portion 40 are formed in a predetermined plurality of sections on the first surface 30a of the base material 30 (element portion forming step). . For example, in FIG. 8B (b), each of the six sections obtained by dividing the first surface 30a of the substrate 30 into two rows in the vertical direction of the paper and dividing into three rows in the horizontal direction of the paper is decorated. Part 60 and 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 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 decorating unit 60 may be collectively referred to as an element unit 70.

  Then, as shown to FIG. 8C, the cutting process which cut | disconnects the base material 30 along each division of the base material 30 is implemented. Thus, the unit intermediate body 35 including the unit base material 22 in which the base material 30 is divided can be formed. Although the method in particular of cutting the base material 30 is not restricted, For example, the base material 30 can be cut | disconnected by the process using a laser. In addition, in order to ensure the flatness and specularity of the cut surface of the base material 30 (side surface 22c of the unit base material 22), the cut surface of the base material 30 may be prepared by etching or polishing after cutting.

  Next, a process of obtaining the cover glass 20 whose side surface is reinforced by providing a reinforcing portion (resin or the like) on the side surface 22c of the unit base member 22 of the unit intermediate 35 will be described with reference to FIGS. 9A and 9B. To do.

  First, an application step of applying the 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 27 containing a urethane type resin and a photoinitiator is used is demonstrated.

  In the coating process, the unit base material 22 is held so that the side surface 22c on which the coating liquid 27 is coated faces upward. In this state, by using a dispenser method, a roll coating method, or the like, the coating liquid 27 is applied on the predetermined side surface 22c of the unit base member 22 as shown in FIG. 9A. Thereafter, the coating liquid 27 is cured by performing a curing process in which the coating liquid 27 is irradiated with light such as ultraviolet rays. Thereby, the reinforcing portion 26 is formed on the predetermined side surface 22 c of the unit base material 22. By performing these coating steps and curing steps on all the side surfaces 22c, as shown in FIG. 9B, the unit base material 22 and the reinforcing portion 26 provided on the side surface 22c of the unit base material 22 The provided cover glass 20 can be obtained.

  In addition, as shown in FIG. 9B, the process of providing the additional decoration part 62 in the position which is the 1st surface 22a side of the unit base material 22 or the 1st surface 26a side of the reinforcement part 26, and is outside the decoration part 60 further. You may implement. The additional decorating unit 62 is configured to exhibit the same color as the decorating unit 60. By further providing such an additional decorative portion 62, the range of the non-active area Aa2 that can exhibit a desired color is expanded to the outside, and the design properties such as prevention of light leakage from the outer peripheral portion are improved. be able to. The additional decorating part 62 is preferably configured to overlap the reinforcing part 26 when viewed along the normal direction of the first surface 20a of the cover glass 20.

  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 the 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. Thereby, it is possible to suppress the occurrence of damage such as cracks on the side surface 22c of the unit base member 22. Thereby, even if the compressive stress layer is not formed on the side surface 22c of the unit base material 22, durability such as impact resistance of the cover glass 20 can be sufficiently increased.

  Moreover, in this Embodiment, the reinforcement part 26 is comprised so that the elastic recovery rate of the reinforcement part 26 may be 0.9 or more as mentioned above. For this reason, after the external force acting on the reinforcing part 26 is removed, the reinforcing part 26 can recover its covering dimension to 90% or more of the initial value by elastic restoration. Accordingly, the reinforcing portion 26 can appropriately protect the side surface 22c of the unit base member 22 from an external force caused by an impact applied thereafter. For this reason, according to this Embodiment, even if it is a case where an impact is applied to the cover glass 20 in multiple times, durability, such as impact resistance of the cover glass 20, can be maintained.

  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 such as chamfering.

  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 reinforcing portion 26 includes the first surface 26a extending from the end 22ae of the first surface 22a to the side on the same plane as the first surface 22a of the unit base member 22, and the unit base. The example which included the 2nd surface 26b extended in the side from the edge part 22be of the 2nd surface 22b on the same plane as the 2nd surface 22b of the material 22 was shown. That is, an example in which there is no or almost no step between the unit base member 22 and the reinforcing portion 26 is shown. However, as long as the side surface 22c of the unit base member 22 can be appropriately protected, the form of the connection portion between the unit base member 22 and the reinforcing portion 26 is not particularly limited. For example, as shown in FIG. 10, the reinforcing portion 26 may be provided so as to cover not only the side surface 22c of the unit base material 22 but also a part of the first surface 22a and / or the second surface 22b of the unit base material 22. Good. Such a reinforcing portion 26 can be manufactured by providing the above-described coating liquid 27 on the side surface 22c of the unit base member 22 by, for example, a dip coating method.

(Second modification)
In the above-described embodiment, the element part forming step for forming the element part 70 such as the decoration part 60 and the touch panel sensor part 40 on the first surface 30a of the base material 30 cuts the base material 30 and is a unit. The example implemented prior to the process of forming the intermediate body 35 and the process of forming the reinforcement part 26 in the side surface 22c of the unit base material 22 of the unit intermediate body 35 was shown. However, it is not restricted to this, You may implement the process of cut | disconnecting the base material 30 with respect to the base material 30 in the state in which the element part 70 is not provided. As shown in FIG. 11, the cover glass 20 may be obtained by forming the reinforcing portion 26 on the side surface 22 c of the unit base member 22 in a state where the element portion 70 is not provided. Thereafter, the element part 70 such as the decoration part 60 or the touch panel sensor part 40 may be formed on the first surface 20 a of the cover glass 20. Alternatively, the decoration unit 60 and the touch panel sensor unit 40 may be separately formed and combined with an adhesive or the like to form the cover glass 20 and then combined with the display device 15.

(Third Modification)
In the second modified example described above, the unit intermediate body 35 is formed by cutting the base material 30 in a state where neither the decoration unit 60 nor the touch panel sensor unit 40 is provided. The example which forms the reinforcement part 26 in the side 22c of the material 22 was shown. However, the present invention is not limited to this, and the step of cutting the base material 30 may be performed on the base material 30 in a state where the touch panel sensor unit 40 is not provided but the decoration unit 60 is provided. Good. Further, as shown in FIG. 12, the reinforcing portion 26 is formed on the side surface 22 c of the unit base material 22 in a state where the touch panel sensor portion 40 is not provided but the decorative portion 60 is provided, thereby obtaining the cover glass 20. May be. Thereafter, the touch panel sensor unit 40 may be formed on the first surface 20 a of the cover glass 20. Alternatively, the touch panel sensor unit 40 may be formed separately and combined with an adhesive or the like to form the cover glass 20 and then combined with the display device 15.

(Fourth modification)
In the present modification, the first protective film 81 and the second protective film 82 provided on the first surface 22a and the second surface 22b of the unit base member 22 are used, and the outer dimensional accuracy is high on the side surface 22c. The example which forms the reinforcement part 26 is demonstrated.

  First, as shown in FIG. 13A, the unit base 22, the first protective film 81 provided on the first surface 22 a of the unit base 22, and the second provided on the second surface 22 b of the unit base 22. A unit intermediate 35 having a protective film 82 is prepared. The first protective film 81 is configured to protrude laterally from the first surface 22 a of the unit base material 22, and the second protective film 82 is on the side of the second surface 22 b of the unit base material 22. It is comprised so that it may protrude in the direction. The first protective film 81 and the second protective film 82 are provided on the first surface 30a and the second surface 30b of the base material 30 before cutting the base material 30 to obtain the unit base material 22. Alternatively, it may be provided on the first surface 22a and the second surface 22b of the unit substrate 22 after the substrate 30 is cut to obtain the unit substrate 22. For example, first, two films that have been cut in advance by die cutting or the like are prepared, and then each film is applied to the first surface 22a and the second surface 22b of the unit base material 22, respectively. The first protective film 81 and the second protective film 82 described above can be provided on the unit base material 22 by removing unnecessary portions. As a material constituting the first protective film 81 and the second protective film 82, for example, biaxially stretched polypropylene or unstretched polypropylene having a thickness of about 50 to 100 μm can be used.

  Thereafter, as shown in FIG. 13B, a coating process is performed in which the coating liquid 27 is filled in the space surrounded by the side surface 22 c of the unit base member 22, the first protective film 81, and the second protective film 82. As shown in FIG. 13B, 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. 13C, 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. For example, 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. 13D, a cover glass 20 including the unit base 22 and the reinforcing portion 26 provided on the side surface 22c of the unit base 22 can be obtained.

  According to the present modification, as described above, the reinforcing portion 26 is formed laterally from the first protective film 81 protruding sideways from the first surface 22a of the unit base material 22 and the second surface 22b of the unit base material 22. It is formed in a space positioned by the protruding second protective film 82. For this reason, as shown in FIG. 13D, the first surface 26a located on the same plane as the first surface 22a of the unit base 22 and the second surface located on the same plane as the second surface 22b of the unit base 22 26b can be obtained more reliably.

  In the present modification, as described above, 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 with a squeegee or the like, A 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 Therefore, the positions of the end portions of the cover glass 20 can be accurately determined by precisely determining the positions of the end surfaces 81c and 82c of the protective films 81 and 82. 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 decoration part 60 and the touchscreen sensor part 40 are provided in the cover glass 20 like this Embodiment, the processing precision of the decoration part 60 and the touchscreen sensor part 40 with respect to the display apparatus 15 can also be raised. Thereby, the high designability and operativity of the display apparatus 10 with a cover glass are realizable.

(Fifth modification)
In this modification, the first protective film 81 and the second protective film 82 described above also function as a resist that protects the element portion 70 when the substrate 30 is divided by wet etching using hydrofluoric acid or the like. Will be described.

  First, the base material 30 provided with the element part 70 is prepared in the same manner as in the case of the above-described embodiment shown in FIGS. 8A and 8B (a) and (b). Next, 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. 14A, a first protective film 81 is provided on the first surface 30 a of the base material 30 so as 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. 14A, as long as the first protective film 81 and the second protective film 82 have resistance to the etching solution used for dividing the first base material 30 of the base material 30, the protective film 81, The material constituting 82 is not particularly limited. For example, as the material constituting the protective films 81 and 82, biaxially stretched polypropylene or unstretched polypropylene having a thickness of about 50 to 100 μm can be used as in the case of the above-described fourth modification. In this case, for example, the protective film 81 is formed by sticking 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. , 82 are configured.

  Thereafter, as shown in FIGS. 14B (a) and 14 (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 second protective film 82, respectively. 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. 14B (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.

  After that, as shown in FIG. 14C (a), a cutting process is performed for cutting the base material 30 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 can be used as described above. Accordingly, as shown in FIG. 14C (a), the unit base 22 made of glass, the element portion 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 intermediate 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. 14C (b) is an enlarged sectional view showing the unit intermediate 35 shown in FIG. 14C (a). As shown in FIG. 14C (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. 14C (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, in the unit base material 22, the first side surface 22 d that intersects the end portion 22 ae and extends outward as it goes to the second surface 22 b side, and the first side surface 22 d that intersects the end portion 22 be and extends outward as it travels toward the first surface 22 a side. Two side surfaces 22e are obtained.

  Next, referring to FIG. 15A to FIG. 15C, 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 intermediate 35. explain.

  First, as shown in FIG. 15A, 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 22 c of the unit base material 22 is performed. 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. 15B, 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. 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. 15C, the 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.

  According to this modification, the first protective film 81 and the second protective film 82 that function as resists during wet etching for cutting the base material 30 are used to increase the height on the side surface 22c of the unit base material 22. The reinforcing part 26 can be formed with an external dimension accuracy. For this reason, the cover glass 20 which has high impact resistance and designability can be obtained with few man-hours.

  In this modification, the example in which the coating liquid 27 is provided so that the surface of the coating liquid 27 coincides with the end surface 81c of the first protective film 81 and the end surface 82c of the second protective film 82 is shown. However, the present invention is not limited to this, and as shown in FIG. 16, the coating liquid 27 is positioned so that the surface of the coating liquid 27 is located inside the end surface 81 c of the first protective film 81 and the end surface 82 c of the second protective film 82. 27 may be provided. Even in this case, the reinforcing portion 26 defined by the first protective film 81 and the second protective film 82 includes the first surface 26a located on the same plane as the first surface 22a of the unit base member 22, and the unit. And the second surface 26b located on the same plane as the second surface 22b of the base material 22.

  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
First, a resin material for constituting the reinforcing portion 26 was prepared, and the pencil hardness was measured. As the resin material, a urethane-based photocurable resin, which is a kind of self-healing resin, was used. Specifically, AU3110 manufactured by Tokushi Co., Ltd. was used. A resin layer made of this resin material was formed on an appropriate substrate, and a hardness test was performed on the resin layer in accordance with DIN50359, thereby evaluating the universal hardness of the resin material. As a result, the universal hardness was 345 N / mm ² .

  Moreover, the cover glass 20 provided with the reinforcement part 26 which consists of the said resin material was produced. Specifically, first, a unit base material 22 was prepared in which the compressive stress layer 24a was formed on the first surface 22a and the second surface 22b, but the compressive stress layer 24a was not formed on the side surface 22c. The thickness of the unit base material 22 was 0.7 mm. Next, the reinforcing portion 26 made of the resin material was formed on the side surface 22c of the unit base material 22. The covering dimension of the reinforcing portion 26 on the side surface 22c was 100 μm.

  Next, the elastic recovery rate of the reinforcement part 26 of the produced cover glass 20 was measured using the above-described method described with reference to FIGS. 6 and 7A to 7C. As a result, the elastic recovery rate was 0.95.

  Moreover, the bending strength of the produced cover glass 20 was measured. As a measuring method, a four-point bending test method was adopted. As a measuring device, a combination of a tensile / compression tester (for example, AG-I manufactured by Shimadzu Corporation) and a four-point bending test jig prepared for a four-point bending test was used. The measuring instrument used is shown in FIG. As shown in FIG. 17, the measuring instrument includes a pair of indenters 91 that press the cover glass 20 from one side of the cover glass 20 and a pair of supports 92 that support the cover glass 20 on the other side of the cover glass 20. And. As the indenter 91 and the support 92, rod-shaped ones that extend along the cover glass 20 are used, although they are not depicted in FIG. 17. The lengths of the indenter 91 and the support 92 in the depth direction of the paper in FIG. 17 were about 15 cm. Further, the distance L ′ between the pair of indenters 91 was 10 mm, and the distance L between the pair of supports 92 was 30 mm. Further, the radius R1 of the tip portion of the pair of indenters 91 was 2.0 mm, and the radius R2 of the tip portion of the pair of support tools 92 was 3.0 mm. Further, the width l of the cover glass 20 to be measured was about 14 cm, the dimension of the cover glass 20 in the depth direction of FIG. 17 was about 7 cm, and the thickness of the cover glass 20 was 0.7 mm. In addition, alignment of the cover glass 20, the indenter 91, and the support tool 92 to be measured was visually performed so that the respective centers coincide.

  In the bending strength measurement process, a pair of indenters 91 is lowered at a displacement rate of 7 mm / mm by applying a load F (a load applied to one inner indenter 91 is F / 2) to the pair of indenters 91. It was. And the load F at the time of the cover glass 20 breaking was made into the intensity | strength of the cover glass 20. FIG.

Measurement of bending strength using the above-described method was performed on the cover glass 20 in the following three states.
(State 1) Cover glass before impact or friction is applied (State 2) Cover glass after impact is applied to the side using a hammer (State 3) Cover glass after the side is rubbed with sandpaper When the state 2 was realized, the direction of impact applied to the cover glass 20 by the hammer was the normal direction of the side surface 22c of the unit base member 22. The magnitude of impact by the hammer was 4.4 mgh, the number of impacts was 5, and the period of impact was 30 seconds.
Moreover, when the state 3 was realized, the sandpaper sweeping direction was a direction orthogonal to the normal direction of the side surface 22c of the unit base member 22, the number of sweeps was three, and the sweep cycle was 30 seconds. As the sandpaper, the one with # 400 is used.

  As a result, the bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 700 MPa, and the bending strength of the cover glass 20 in the state 3 was 650 MPa.

(Example 2)
A cover glass 20 provided with the reinforcing portion 26 was produced in the same manner as in Example 1 except that the covering dimension of the reinforcing portion 26 was 150 μm. Further, in the same manner as in Example 1, the elastic recovery rate and bending strength of the produced cover glass 20 were measured. As a result, the elastic recovery rate was 0.95. Moreover, the bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 750 MPa, and the bending strength of the cover glass 20 in the state 3 was 700 MPa.

(Example 3)
A cover glass 20 provided with the reinforcing portion 26 was produced in the same manner as in Example 1 except that the covering dimension of the reinforcing portion 26 was 50 μm. Further, in the same manner as in Example 1, the elastic recovery rate and bending strength of the produced cover glass 20 were measured. As a result, the elastic recovery rate was 0.95. The bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 550 MPa, and the bending strength of the cover glass 20 in the state 3 was 500 MPa.

Example 4
As a resin material for constituting the reinforcing portion 26, an epoxy resin in which fine particles made of SiO ₂ were dispersed was prepared. The particle size of the fine particles was in the range of 50 to 250 nm. Further, in the same manner as in Example 1, the universal hardness of this resin material was evaluated. As a result, the universal hardness was 715 N / mm ² .

  Moreover, the cover glass 20 provided with the reinforcement part 26 which consists of the said resin material similarly to the case of Example 1 was produced. The covering dimension of the reinforcing portion 26 on the side surface 22c was 50 μm. Further, in the same manner as in Example 1, the elastic recovery rate and bending strength of the produced cover glass 20 were measured. As a result, the elastic recovery rate was 0.98. The bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 750 MPa, and the bending strength of the cover glass 20 in the state 3 was 750 MPa.

(Example 5)
As a resin material for constituting the reinforcing part 26, an epoxy resin in which fine particles of carbon black are dispersed was prepared. The particle size of the fine particles was in the range of 10 to 500 nm. Further, in the same manner as in Example 1, the universal hardness of this resin material was evaluated. As a result, the universal hardness was 635 N / mm ² .

  Moreover, the cover glass 20 provided with the reinforcement part 26 which consists of the said resin material similarly to the case of Example 1 was produced. The covering dimension of the reinforcing portion 26 on the side surface 22c was 50 μm. Further, in the same manner as in Example 1, the elastic recovery rate and bending strength of the produced cover glass 20 were measured. As a result, the elastic recovery rate was 0.98. Moreover, the bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 700 MPa, and the bending strength of the cover glass 20 in the state 3 was 700 MPa.

(Example 6)
A urethane acrylate resin was prepared as a resin material for constituting the reinforcing portion 26. Further, in the same manner as in Example 1, the universal hardness of this resin material was evaluated. As a result, the universal hardness was 435 N / mm ² .

  Moreover, the cover glass 20 provided with the reinforcement part 26 which consists of the said resin material similarly to the case of Example 1 was produced. The covering dimension of the reinforcing portion 26 on the side surface 22c was 50 μm. Further, in the same manner as in Example 1, the elastic recovery rate and bending strength of the produced cover glass 20 were measured. As a result, the elastic recovery rate was 0.91. The bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 650 MPa, and the bending strength of the cover glass 20 in the state 3 was 550 MPa.

(Comparative Example 1)
A cover glass 20 that was the same as in Example 1 was prepared except that the reinforcing portion 26 was not provided. The bending strength of the cover glass 20 was measured in the same manner as in Example 1. As a result, the bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 200 MPa, and the bending strength of the cover glass 20 in the state 3 was 200 MPa.

(Comparative Example 2)
Except that the reinforcing substrate 26 is not provided and the unit base material 22 in which the compressive stress layer 24a is formed on any of the first surface 22a, the second surface 22b, and the side surface 22c is used. A cover glass 20 identical to that in Example 1 was prepared. The bending strength of the cover glass 20 was measured in the same manner as in Example 1. As a result, the bending strength of the cover glass 20 in the state 1 was 800 MPa, the bending strength of the cover glass 20 in the state 2 was 750 MPa, and the bending strength of the cover glass 20 in the state 3 was 700 MPa.

(Comparative Example 3)
An epoxy resin was prepared as a resin material for constituting the reinforcing portion 26. Further, in the same manner as in Example 1, the universal hardness of this resin material was evaluated. As a result, the universal hardness was 250 N / mm ² .

  Moreover, the cover glass 20 provided with the reinforcement part 26 which consists of the said resin material similarly to the case of Example 1 was produced. The covering dimension of the reinforcing portion 26 on the side surface 22c was 100 μm. Further, in the same manner as in Example 1, the elastic recovery rate and bending strength of the produced cover glass 20 were measured. As a result, the elastic recovery rate was 0.75. Moreover, the bending strength of the cover glass 20 in the state 1 was 750 MPa, the bending strength of the cover glass 20 in the state 2 was 200 MPa, and the bending strength of the cover glass 20 in the state 3 was 200 MPa.

The measurement results in Examples 1 to 6 and Comparative Examples 1 to 3 are summarized in Table 1.

  As can be seen from the comparison between Examples 1 to 6 and Comparative Examples 1 and 3, by providing the reinforcing portion 26 having an elastic recovery rate of 0.9 or more, after impact and friction are applied by a hammer or sandpaper Even so, a bending strength of 500 MPa or more could be achieved. As can be seen from the comparison between Examples 1, 2, 4, and 5 and Comparative Example 2, in Examples 1, 2, 4, and 5, any of the first surface 22a, the second surface 22b, and the side surface 22c is used. Bending strength equivalent to that of the unit base material 22 on which the compressive stress layer 24a is formed could be realized. It can be seen that the reinforcing portion 26 according to the present invention is very effective in protecting the cover glass 20 after impact or friction is applied.

  As can be seen from the comparison between Examples 1 and 2 and Example 3, when the reinforcing part 26 is made of urethane resin, impact and friction due to hammer and sandpaper are added by setting the covering dimension to 100 μm or more. Even after being bent, a bending strength of 650 MPa or more could be achieved. When the reinforcement part 26 is comprised with urethane type resin, it turns out that it is very effective to make a coating dimension into 100 micrometers or more.

DESCRIPTION OF SYMBOLS 10 Display apparatus with cover glass 15 Display apparatus 20 Cover glass 22 Unit base material 22a 1st surface 22b 2nd surface 22c Side surface 24a Compressive stress layer 24b Tensile stress layer 26 Reinforcement part 26a 1st surface 26b 2nd surface 26c Side surface 27 Coating liquid DESCRIPTION OF SYMBOLS 30 Base material 35 Unit intermediate body 40 Touch panel sensor part 60 Decoration part 62 Additional decoration part 70 Element part 81 1st protective film 81c End surface 82 2nd protective film 82c End surface

Claims (11)

A cover glass provided on the viewer side of the display device,
A unit substrate made of glass, including a first surface facing the display device side, a second surface on the opposite side of the first surface, and a side surface extending between the first surface and the second surface;
A reinforcing portion made of a resin material provided on the side surface of the unit base material,
The maximum deformation of the reinforcing portion when the reinforcing portion is pushed toward the unit base material using an indenter so that the ratio of the maximum deformation amount of the reinforcing portion to the covering dimension of the reinforcing portion is 0.3. A cover glass in which a ratio of an elastic deformation amount of the reinforcing portion to an amount is 0.9 or more.   The cover glass according to claim 1, wherein a ratio of the elastic deformation amount of the reinforcing portion to the maximum deformation amount of the reinforcing portion is 0.98 or less. The cover glass of Claim 1 or 2 whose universal hardness of the said reinforcement part exists in the range of 300-750 N / mm < ² >.   The reinforcing portion has a time required for recovering the covering dimension of the reinforcing portion from a state where the deformation amount of the reinforcing portion is the maximum deformation amount over a portion of at least 90% of the elastic deformation amount. The cover glass according to any one of claims 1 to 3, wherein the cover glass is configured to be within seconds. The resin material constituting the reinforcing part includes a urethane-based resin,
The cover glass as described in any one of Claims 1 thru | or 4 whose covering dimension of the said reinforcement part is 100 micrometers or more. The unit base material includes at least a compressive stress layer formed on the first surface and the second surface, and the compressive stress layer on the first surface side and the compressive stress layer on the second surface side. A tensile stress layer located,
The cover glass according to any one of claims 1 to 5, wherein the tensile stress layer is exposed on the side surface of the unit base material.   The cover glass as described in any one of Claims 1 thru | or 6 with which the decorating part which exhibits a predetermined color is provided on the said 1st surface of the said unit base material.   The cover glass according to claim 7, wherein the decoration portion is configured to overlap the reinforcement portion when viewed along the normal direction of the cover glass.   The cover glass as described in any one of Claims 1 thru | or 8 with which at least one part of the touchscreen sensor part is provided on the said 1st surface of the said unit base material.   The reinforcing portion includes a first surface extending laterally from an end of the first surface of the unit base material on the same plane as the first surface of the unit base material, and the second surface of the unit base material. The cover glass as described in any one of Claims 1 thru | or 9 containing the 2nd surface extended to the side from the edge part of the said 2nd surface of the said unit base material on the same plane as a surface. A display device;
A cover glass disposed on the viewer side of 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 10.