JP2015138282A - Cover glass-integrated touch panel and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cover glass-integrated touch panel that is obtained by cutting a large glass substrate where a plurality of unit cover glass-integrated touch panels is formed, and that has excellent characteristics in impact resistance against falling or scratch resistance.SOLUTION: The cover glass-integrated touch panel includes a display region 30, a frame part 20 covering a periphery of the display region, and an overcoat layer 6 entirely covering the display region and the frame part, formed on one surface of a glass substrate, and a protective layer 7 entirely covering the panel including end faces thereof. The display region comprises a plurality of X-axis detection sensors 1, a plurality of Y-axis detection sensors 2, and an insulating layer 3. The frame part covers a plurality of lead-out wires 5 drawn from the X-axis detection sensors and Y-axis detection sensors. The overcoat layer is formed flat on the display region and the frame part. The protective layer is made of a resin and has at least impact resistance and scratch resistance.

Description

  The present invention relates to a capacitive touch panel used for a liquid crystal display, in particular, a cover glass integrated touch panel and a method for manufacturing the same.

  2. Description of the Related Art In recent years, a capacitive touch panel sensor substrate (hereinafter referred to as a touch panel) has been adopted for an operation unit of an electronic device such as a mobile phone or a portable information terminal. Generally, a touch panel consists of a display area and a frame part, and a front plate is provided on the outermost surface, and there are a film type and a glass type. The film type is lightweight, hard to break, inexpensive to manufacture, and flexible, so it has the merit that it is easy to remove bubbles when bonding with other display devices and cover glass, but the light transmission of the film The rate is low compared to glass, and the positional accuracy of the wiring pattern formed on the film is inferior to that of glass, so the frame area covering the lead-out wiring becomes large and the display area becomes narrow, Due to the difference in smoothness, there is a problem that it looks worse than the glass type. In small products such as smart phones and tablet computers that require high definition and low power consumption, many glass types are used. (See Patent Document 1)

  As shown in FIG. 2, the display area 30 is composed of a sensor made of a transparent conductive material, and includes an X-axis direction detection sensor 1 and a Y-axis direction detection sensor 2, and further, the X-axis direction detection sensor 1 and Y. An insulating layer 3 is formed in the vicinity of the crossing of the axial direction detecting sensor 2, and an overcoat layer 6 for imparting flattening and a protective layer 7 for imparting resistance are laminated thereon.

  On the other hand, the frame portion 20 covers a plurality of lead wires 5 drawn out from the X-axis and Y-axis direction sensors, and the protective layer 7 is laminated on the display region 30 in the same manner as the display region 30, and the appearance and It greatly affects reliability.

  Conventionally, a small touch panel used in a mobile phone or the like generally has a plurality of unit touch panels 40 formed on a large glass substrate 50 as shown in FIG. Have been made.

The large glass substrate, a SiO _{2, Al} and 2 _{O 3,} with at least one alkali metal oxide as is generally reinforced treated aluminosilicate glass containing selected from Li ₂ O and Na ₂ O, It is done. The glass strengthening treatment includes physical strengthening (air cooling strengthening) that rapidly cools after heating the glass surface to near the softening point and chemical strengthening that replaces alkali ions inside the glass with alkali ions having a larger particle size. A thin plate of 1 mm or less used for a cellular phone is not suitable for physical strengthening because the temperature difference between the surface and the inside is difficult to be applied, and chemical strengthening is generally used.

  The chemical strengthening of glass involves immersing the glass in a molten salt below the glass transition point, and replacing the alkali ions inside the glass with alkali ions having a larger ionic radius, thereby reducing the compressive stress due to the difference in ionic radius. It is a method to generate. By generating compressive stress on the glass surface, the strength of the glass is improved in order to prevent tensile stress from concentrating on the scratches generated on the glass surface.

However, chemically strengthened glass has problems that it is difficult to cut due to strength during cutting, and that it is difficult to cut because it breaks irregularly due to large compressive stress. Therefore, a method has been proposed in which a large glass substrate before the tempering treatment is cut into a small glass substrate, the tempering treatment is performed, and a small tempered glass substrate is obtained after firing. However, this method has a problem that productivity is lowered because chemical strengthening is performed after cutting.

JP 2009-69321 A JP 2012-148957 A

  The present invention is the unit touch panel obtained by cutting from a large glass substrate on which a plurality of unit cover glass-integrated touch panels are formed, and has a cover glass having excellent impact resistance and scratch resistance against dropping. The purpose is to provide an integrated touch panel.

As means for solving the above-mentioned problems, the invention according to claim 1 is characterized in that a display region, a frame portion covering the outer periphery thereof, and the display region and the frame portion are provided on one surface of the glass substrate. An overcoat layer covering the whole is formed, and further the cover glass integrated touch panel in which the whole including the end face is covered with a protective layer,
The display area includes a plurality of X-axis direction detection sensors, a Y-axis direction detection sensor, and an insulating layer,
The frame portion covers a plurality of lead wires led out from the X-axis direction detection sensor and the Y-axis direction detection sensor,
The overcoat layer is formed flat on the display area and the frame portion,
The protective glass is a cover glass-integrated touch panel characterized in that it is made of a resin and has at least impact resistance and scratch resistance.

  The invention described in claim 2 is characterized in that the resin contains at least one of polyurethane resin, polyester resin, silicone resin, acrylic resin, and methacrylic resin. This is a cover glass integrated touch panel.

According to a third aspect of the present invention, there is provided a method for forming a Y-axis direction detection sensor on one surface of a glass substrate and a Y-axis direction detection sensor in the vicinity of the intersection of the X-axis direction detection sensor. Forming an insulating layer; forming an X-axis direction detection sensor; forming an extraction wiring from each of the X-axis direction detection sensor and the Y-axis direction detection sensor; and covering the extraction wiring And forming a unit cover glass integrated touch panel through a step of forming a frame portion and a step of forming an overcoat layer flatly on the display region and the frame portion,
Cutting for each unit cover glass integrated touch panel;
It is a manufacturing method of a cover glass integrated touch panel characterized by comprising a step of forming a protective layer on the whole including the end face of the cut unit cover glass integrated touch panel.

  According to a fourth aspect of the present invention, in the cover glass-integrated touch panel according to the third aspect, the method for forming the protective layer is formed by transferring a protective layer previously formed on a peeling substrate. It is a manufacturing method.

According to claims 1 and 3 of the present invention, after cutting a plurality of unit cover glass integrated touch panels formed on a large glass substrate, the whole is covered with a protective layer made of resin,
In addition to the front and back of the touch panel, the cut surface of the glass substrate can be reinforced.
As a result, impact resistance and scratch resistance are improved, and damage due to dropping or the like can be prevented.

  According to claim 2, by forming a protective layer made of a resin containing at least one of polyurethane resin, polyester resin, silicone resin, acrylic resin, and methacrylic resin, at least impact resistance and Scratch resistance can be improved.

  According to claim 4, as a method of forming the protective layer, productivity is improved by performing a protective layer previously formed on the peeling substrate by transfer, and stable quality and cost reduction can be achieved.

  By providing the cover glass-integrated touch panel formed as described above, it is possible to provide a display device excellent in appearance shape and reliability.

The cross-sectional schematic diagram of the cover glass integrated touch panel which concerns on this invention. The cross-sectional schematic diagram of the conventional touch panel. The plane schematic diagram of a touch panel. FIG. 4 is a partially enlarged view of FIG. 3. FIG. 4 is a schematic diagram of multiple imposition of FIG. 3.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  The cover glass integrated touch panel of the present invention cuts a plurality of unit touch panels (hereinafter referred to as touch panels) 40 formed on a large glass substrate 50 as shown in FIG. It is characterized by being coated.

  FIG. 1 is a schematic cross-sectional view of a capacitive cover glass integrated touch panel according to the present invention.

  Specifically, the touch panel 40 of the present invention covers one surface of the glass substrate 10 with the display region 30, the frame portion 20 covering the outer periphery thereof, and the entire display region 30 and the frame portion 20. The overcoat layer 6 is formed, and the whole is further covered with the protective layer 7. More specifically, the display area 30 includes a plurality of X-axis direction detection sensors 1, a Y-axis direction detection sensor 2, and an insulating layer 3, and the frame portion 20 includes the X-axis direction detection sensor 1 and A plurality of lead wires 5 drawn from the Y-axis direction detection sensor 2 are covered, and the overcoat layer 6 is formed flat on the display region 30 and the frame portion 20, and further entirely made of resin. The protective layer 7 is covered.

  In the touch panel 40 of the present invention, the entire touch panel 40 is covered with the protective layer 7 described above, so that particularly the impact resistance and scratch resistance of the cut surface are improved, and damage due to dropping or the like can be prevented. .

  FIG. 3 shows a plan view of an embodiment of the touch panel of the present invention. The touch panel of the present invention includes an X-axis direction detection sensor 1 and a Y-axis direction detection sensor 2 made of a transparent conductive layer, a display region 30 composed of an insulating layer 3 that insulates the vicinity of the intersection, and the display region. It is comprised from the frame part 20 which has the concealment property which covers 30 outer periphery.

4 is an enlarged plan view of the display area 30 shown in FIG. 3A, that is, the vicinity where the X-axis direction detection sensor 1 and the Y-axis direction detection sensor 2 intersect. Specifically, the insulating layer 3 is formed on the wiring of the Y-axis direction detection sensor 2 to prevent a short circuit with the wiring of the X-axis direction detection sensor 1. The shape of the insulating layer 3 is not particularly limited as long as the wiring of the Y-axis direction detection sensor 2 can be covered.

  The frame portion 20 is formed of a light shielding layer 4 having a concealing property, and covers the lead-out wiring 5 that connects the X-axis direction detection sensor 1 and the Y-axis direction detection sensor 2 to the control circuit. Thereby, visual recognition of the lead-out wiring 5 can be prevented and the width of the design can be expanded.

As the large glass substrate 50 used in the present invention, generally, a glass substrate produced by a method such as a float method, a slit down draw method, a fusion down draw method, or a redraw method can be used. A glass substrate containing an alkali metal oxide capable of ion exchange treatment is preferable. For example, a known glass substrate such as aluminosilicate glass containing at least one alkali metal oxide selected from SiO ₂ , Al ₂ O ₃ , Li ₂ O, and Na ₂ O, or soda lime glass is used. be able to. Of these, aluminosilicate glass is more preferable because strength is important.

  The glass substrate can be cut by a break method, a laser cut method, a water jet flow method, or the like. It is also possible to cut the surface provided with the etching resistant film in combination with a method of immersing in the etching solution. In this case, for example, the etching solution is not particularly limited as long as it contains at least hydrofluoric acid, but if necessary, other acids such as hydrochloric acid and various additives such as a surfactant are added. Also good.

  However, by using the aminosilicate glass as described above, the strength of the glass substrate surface can be maintained, but by cutting, the strength of the cut end portion is reduced. As a countermeasure, for example, a method of performing a chemical strengthening process after cutting and further firing is performed. However, there is a problem that productivity is lowered by going through the complicated steps as described above. The present invention solves such problems.

  Specifically, the protective layer 7 described below covers the entire cut surface of the display region 30, the frame layer 20, and the glass substrate 10 to prevent a reduction in strength of the cut edge due to cutting. It is characterized by.

  The resin used for the protective layer 7 is not particularly limited as long as it is excellent in transparency, adhesion, and reliability, but among them, polyurethane resin, polyester resin, silicone resin, acrylic resin A resin containing at least one of a resin and a methacrylic resin is preferable. These resins are particularly excellent in impact resistance and scratch resistance, and are effective for reinforcing the end face of the cut glass substrate. Moreover, what consists of an ultraviolet curable resin composition from the surface of productivity or quality is preferable. The ultraviolet curable resin composition according to the present invention includes a transparent resin having a polymerizable reactive group, a reactive diluent (monomer), a photopolymerization initiator, an additive, and the like.

  As a method for forming the protective layer 7, a direct method in which a resin composition is directly applied, dried and cured, or an indirect method by a transfer method can be used.

  As the direct method, for example, the resin composition can be applied to the entire surface of the cut unit touch panel 40 by spraying or can be applied by dipping in the resin composition. Moreover, it can also apply | coat to the front and back of the unit touch panel 40, and a cutting surface with a roll coat etc., respectively.

Moreover, the indirect method which forms the resin composition in the predetermined film thickness in the base material which has peelability previously, transfers it, and forms the protective layer 7 can also be used. In this case, the resin composition is preferably an ultraviolet curable resin composition. For example, it is applied to the substrate having the peelability and dried to temporarily form a transfer layer, and then transferred to a touch panel and then irradiated with ultraviolet rays. Thus, curing can be completed and a protective layer can be formed. This method is preferable in that the process can be simplified because a separate transfer layer is formed, and productivity is improved due to curing with ultraviolet rays.

  As described above, according to the present invention, since the cut end portion of the glass substrate is also covered with the protective layer made of a resin, a touch panel that is particularly excellent in impact resistance and scratch resistance against dropping is provided compared to the related art. be able to. By adjusting the resin composition, functions such as antireflection, antifouling, and antistatic can be imparted in addition to impact resistance and scratch resistance.

  Hereinafter, various layers constituting the touch panel sensor according to the present invention will be described.

  The X and Y axis direction detection sensors can be formed of a transparent conductive layer. As the transparent conductive layer, a metal oxide is preferable. For example, indium tin oxide (ITO), tin oxide, indium oxide, zinc oxide, or the like can be used. Of these, ITO is preferable. A thin film of these metal oxides can be formed on the glass substrate 1 by vapor deposition or sputtering, and then the sensor can be formed by photolithography.

The insulating layer 3 can be made of an inorganic film such as SiO ₂ or SiN _x or an organic material such as a transparent resin. Since inorganic films such as SiO ₂ and SiN _x are formed by CVD, sputtering, or the like, there is a problem that the manufacturing cost becomes high, such as an increase in energy consumption and the number of processes. A material system is preferred. As the organic material system, an ultraviolet curable resin composition containing a polymerizable group-containing oligomer, monomer, photopolymerization initiator, additive and the like can be used.

  When an organic material system is used for the insulating layer 3, for example, a pattern can be formed by a printing method such as screen printing or gravure offset printing, but the printing method to be used is not particularly limited.

  The light shielding layer 4 corresponds to the frame portion 20 and is formed so as to cover the outer periphery of the display region 30. Further, the frame portion 2 needs to be formed of a concealing material in order to conceal the lead-out wiring 5. For example, it can be formed by blending a resin with black or other colored pigment alone, or by mixing a colored pigment to adjust a colored pigment composition. Further, it can be formed as a single layer or a multilayer.

  The evaluation of the light shielding property is generally represented by an optical density (Optical Density), which is also referred to as an OD value. The measurement is performed using a Macbeth optical densitometer or the like in accordance with the JIS-K-7605 standard, and is obtained by irradiating the sample with a vertically transmitted light beam and expressing the ratio of the state without the sample with log (logarithm). . The higher the optical density, the lower the transmittance, and the optical density becomes 0 at a transmittance of 100%. The OD value of the frame is preferably 4.0 or more in order to conceal the lead-out wiring and suppress light leakage from the display.

  As the method for forming the light shielding layer 4, either a method of directly printing a pattern or a method of indirectly transferring a pattern previously formed on another substrate is possible. The direct printing method is desirable, and the screen printing method is more desirable.

  The lead wiring 5 can be made of various metal materials, and Mo (molybdenum), Al (aluminum), Ag (silver), Cu (copper), Pd (palladium), etc. are preferable, and Mo / Al / A three-layer structure of Mo is more preferable. For example, by sputtering, a film having a thickness of about Mo / Al / Mo = 350 mm / 2000 mm / 350 mm is formed, and after a photolithography process using a positive resist, an etching process and a resist peeling process are performed to form a lead-out wiring. The method is widely used.

  The overcoat layer 6 includes an X-axis direction detection sensor, a Y-axis direction display sensor, a display region 30 including an insulating layer 3 in the vicinity of the intersection, a light shielding layer 4 and a lead wiring 5. This is to make the frame part 20 flat. Therefore, it is preferable to be made of a material having fluidity, transparency, adhesion, and the like that can easily enter the uneven shape of the surface formed by each layer and member. Among these, an ultraviolet curable resin composition is preferable because of its excellent productivity and cured film characteristics.

  In addition, there may be a region where the overcoat layer or the protective layer or both are not provided, if necessary, such as the terminal region.

  The present invention can be used as a touch panel for a liquid crystal display body in both small and large display devices.

DESCRIPTION OF SYMBOLS 1 X-axis direction detection sensor 2 Y-axis direction detection sensor A Near intersection of X-axis and Y-axis direction detection sensor 3 Insulating layer 4 Light-shielding layer 5 Lead-out wiring 6 Overcoat layer 7 Protective layer 10 Glass substrate 20 Frame part 30 Display area 40 Unit touch panel 50 Large glass substrate

Claims (4)

On one surface of the glass substrate, a display region, a frame portion covering the outer periphery thereof, an overcoat layer covering the entire display region and the frame portion are formed, and the entire surface including the end surface is a protective layer. A covered cover glass integrated touch panel,
The display area includes a plurality of X-axis direction detection sensors, a Y-axis direction detection sensor, and an insulating layer,
The frame portion covers a plurality of lead wires led out from the X-axis direction detection sensor and the Y-axis direction detection sensor,
The overcoat layer is formed flat on the display area and the frame portion,
The cover glass-integrated touch panel, wherein the protective layer is made of a resin and has at least impact resistance and scratch resistance.   The cover glass-integrated touch panel according to claim 1, wherein the resin includes at least one of a polyurethane resin, a polyester resin, a silicone resin, an acrylic resin, and a methacrylic resin. Forming a Y-axis direction detection sensor on one surface of the glass substrate, forming an insulating layer on the Y-axis direction detection sensor in the vicinity of the intersection with the X-axis direction detection sensor, and the X-axis direction. Forming a detection sensor; forming a lead-out line from each of the X-axis direction detection sensor and the Y-axis direction detection sensor; forming a frame portion covering the lead-out line; After forming a plurality of unit cover glass integrated touch panel through a process of forming an overcoat layer flat on the display area and the frame portion,
Cutting for each unit cover glass integrated touch panel;
The manufacturing method of the cover glass integrated touch panel characterized by including the process of forming a protective layer in the whole including the end surface of the cut unit cover glass integrated touch panel.   The method for manufacturing a cover glass-integrated touch panel according to claim 3, wherein the protective layer is formed by transferring a protective layer previously formed on a peeling substrate.