WO2012161078A1

WO2012161078A1 - Printing film for touch panel, cover glass for touch panel, liquid crystal display panel, multi-function terminal, and method for manufacturing printing film for touch panel

Info

Publication number: WO2012161078A1
Application number: PCT/JP2012/062643
Authority: WO
Inventors: 梅田　昌弘
Original assignee: Umeda Masahiro
Priority date: 2011-05-20
Filing date: 2012-05-17
Publication date: 2012-11-29
Also published as: TW201248254A

Abstract

This printing film for a touch panel, which is bonded to the body of the touch panel, is provided: with a base film; a frame-shaped printing layer which is disposed on one surface of the base film; and a transparent resin layer for optics formed by applying a liquid-curable-type transparent resin composition for optics over the surface of the printing layer and the one surface of the base film inside the frame of the printing layer, and curing the transparent resin composition such that the surface becomes flat.

Description

PRINTING FILM FOR TOUCH PANEL, COVER GLASS FOR TOUCH PANEL, LIQUID CRYSTAL DISPLAY PANEL, MULTIFUNCTIONAL TERMINAL, AND METHOD FOR PRODUCING PRINTING FILM FOR TOUCH PANEL

The present invention relates to a printing film for a touch panel, a cover glass for a touch panel, a liquid crystal display panel, a multifunction terminal, and a method for producing a printing film for a touch panel.

In recent years, the main role of touch panels mounted on mobile phones and tablet PCs (hereinafter simply referred to as devices) is changing from resistive film type to electrostatic capacitance type, in particular, projected electrostatic capacitance type. Since the projected capacitive touch panel does not require deformation of the touch panel like the resistive film type and can be made of a rigid body, the protective sheet for the touch panel is made of glass (cover glass with high light transmission and high gloss and hardness). ) Can be adopted.

On this cover glass, an image such as a frame having a predetermined pattern for hiding the electrode wiring of the touch panel and an icon for touch panel operation is directly printed on the outer periphery of the screen display part by silk printing (screen printing). become. However, unlike a flexible film that can be printed continuously in a roll, a rigid cover glass cannot be rolled, so it must be printed on a sheet-by-sheet basis, and frame printing is extremely difficult. Expensive.

Therefore, an inexpensive method for indirectly printing on a cover glass by attaching a print film to the cover glass instead of directly printing a frame or an image on the cover glass has been attempted. The printing part printed on the printing film also has a step. A printing film having this printing step is attached to a cover glass using an ultraviolet curable resin (UV curable resin) or an optical transparent adhesive tape.

In the pasting method using a UV curable resin, the UV curable resin is in a liquid state before being cured, so it is possible to absorb the printing step and prevent the generation of bubbles at the printing step. It was difficult to avoid overhang, and handling was troublesome. On the other hand, in the pasting method using the optical transparent adhesive tape, the optical transparent adhesive is already gelled and cured, so that it can be prevented from protruding during bonding and easy to handle. There is a problem that adhesion failure such as peeling and foaming occurs (for example, see Non-Patent Document 1).

Today, the pasting method using a transparent adhesive tape for optics, which is better handled than UV curable resin, has become the mainstream. Attempts have been made to solve the above-described problems in the attaching method using the optical transparent adhesive tape by making the printing a step and making it easier to place the OCA or attaching it under vacuum. However, the problem of poor adhesion has not been solved.

The object of the present invention is to solve the above-mentioned problems of the prior art, and achieve both the absorption of the printing step, which has not been solved in the past, and the prevention of the resin sticking out at the time of bonding. It is in providing the manufacturing method of the printing film for touchscreens, the cover glass for touchscreens, a liquid crystal display panel, a multifunction terminal, and the printing film for touchscreens which can reduce the adhesion failure of this.

According to one aspect of the invention,
A touch panel printing film to be bonded to the touch panel body,
A base film;
A frame-shaped printing layer provided on one surface of the base film;
Optically formed by applying a liquid curable optical transparent resin composition over the surface of the printed layer and one surface of the substrate film in the frame of the printed layer and curing the surface to be flat. A printed film for a touch panel provided with a transparent resin layer is provided.

According to another aspect of the invention,
A touch panel printing film to be bonded to the touch panel body,
A base film;
A printing layer provided on one surface of the base film;
A gel-like first optically transparent adhesive layer provided on the other surface of the base film;
A frame formed around a window opened by punching the first optically transparent adhesive layer, the base film, and the printed layer in a layer thickness direction;
A liquid curable optical transparent adhesive is applied over the surface of the frame on the printed layer side and the inside of the window, and the surface of the frame and the surface of the window, and the first optical transparent adhesive. There is provided a printed film for a touch panel provided with a second optically transparent adhesive layer formed by curing the back surface of the frame on the layer side and the back surface of the window in a gel shape so as to be flat.

Also, touch panel cover glass, liquid crystal display panel, and multi-function terminal to which a touch panel print film is attached are provided.

According to another aspect of the present invention,
A method for producing a printed film for a touch panel to be bonded to a touch panel body,
Forming a frame-shaped printed layer on one surface of the base film;
A liquid curable optical transparent resin composition is applied over the surface of the printed layer and one surface of the substrate film in the frame of the printed layer to absorb the thickness of the printed layer, and to cure and gel Forming a transparent optical resin layer,
The manufacturing method of the printed film for touchscreens containing is provided.

According to the present invention, it is possible to significantly reduce adhesion failure with a glass to be deposited such as a cover glass.

It is a manufacturing-process figure of the touchscreen by the 1st Embodiment of this invention. It is a manufacturing-process figure of the touchscreen by the 2nd Embodiment of this invention. It is a manufacturing-process figure of the touchscreen by the 3rd Embodiment of this invention. It is a manufacturing-process figure of the printing film for touchscreens by the 4th Embodiment of this invention. It is sectional drawing of the touchscreen by the 1st Embodiment of this invention. It is sectional drawing of the touchscreen by the 2nd Embodiment of this invention. It is sectional drawing of the touchscreen by the 3rd Embodiment of this invention. It is sectional drawing of the touchscreen by the 4th Embodiment of this invention. It is a partial top view of the large format base film for taking many printing films for touchscreens by one embodiment of this invention. It is a disassembled block diagram of the display apparatus by Example 1 of this invention. It is a disassembled block diagram of the display apparatus by Example 2 of this invention. It is a disassembled block diagram of the display apparatus by Example 3 of this invention. It is a disassembled block diagram of the display apparatus by Example 4 of this invention. It is a disassembled block diagram of the display apparatus by Example 5 of this invention. It is a disassembled block diagram of the display apparatus by Example 6 of this invention. It is a disassembled block diagram of the display apparatus by Example 7 of this invention. It is a disassembled block diagram of the display apparatus by Example 8 of this invention.

Hereinafter, embodiments of the present invention will be described.

As described above, a rigid capacitance type that does not require deformation, particularly a projection type capacitive touch panel, has been adopted, and a cover glass, particularly tempered glass, has been used for the protective sheet. Since direct printing on the cover glass is expensive, indirect printing in which the print film is bonded to the cover glass via a UV curable resin or an optical transparent adhesive tape (OCA tape) has become the mainstream. When the printing film is bonded to the cover glass via the UV curable resin, the printing step can be absorbed, but there is a problem that it protrudes. In addition, when the print film is bonded to the cover glass via the OCA tape, the print film does not protrude, but bubbles due to the printing steps are generated, resulting in poor adhesion.
Therefore, the present invention takes advantage of the advantages of UV curable resin and OCA, and the optical transparent resin layer is in a liquid state so that the printing step of the printing film can be absorbed before the printing film is bonded to the cover glass. When the printing film is bonded to the cover glass, it is already cured, so that both the absorption of the printing step and the prevention of the resin protrusion can be achieved. Well, the printing film is a color-added printing film so that colors that cannot be obtained by BM (Black Matrix) can be produced.

[First Embodiment]
In the manufacturing method of the touch-panel print film to be attached to the cover glass that protects the rigid touch panel body according to the present embodiment, a step of forming a frame-shaped print layer on one surface of the base film to be attached to the cover glass; A step of applying a transparent liquid transparent adhesive composition for laminating the cover glass on the entire surface of the base film on which a printed layer is formed; and the liquid transparent adhesive composition applied on the entire surface of the base film. And a step of curing the product into a gel to form a first optical transparent adhesive layer. When the liquid transparent adhesive composition is applied, the step of the printed layer formed on the base film is easily absorbed. Therefore, when a base film having a printed step is bonded to the cover glass, peeling or foaming is unlikely to occur.

Moreover, in the manufacturing method of the cover glass for touchscreens by this Embodiment, the cover glass obtained by the manufacturing method of the printing film for touchscreens mentioned above is made into the said cover glass through the said 1st optically transparent adhesive layer. I'm trying to paste it on one side. Since the base film is attached to the cover glass after the pressure-sensitive adhesive is cured in a gel form to form the first transparent adhesive layer for optics, adhesion failure due to peeling or foaming hardly occurs. Further, since the optical transparent adhesive layer is cured after being gelled, the optical transparent adhesive layer is difficult to protrude.

Further, in the touch panel manufacturing method according to the present embodiment, the touch panel cover glass obtained by the touch panel cover glass manufacturing method described above is formed on the entire other surface opposite to the one surface of the cover glass. It is made to affix on the said touch-panel main body through the transparent adhesive layer for optics. The other surface opposite to the one surface of the cover glass is a bare surface and has no step, and even when directly attached to the touch panel body via the second optical transparent adhesive layer, adhesion failure due to peeling or foaming hardly occurs. Therefore, adhesion failure between the cover glass and the touch panel can be eliminated.

Hereinafter, the first embodiment will be described in detail with reference to FIG.

<Configuration of touch panel>
FIG. 5 illustrates the structure of the touch panel according to the first embodiment. The touch panel 10 mainly includes a touch panel body 11, a cover glass 21 that protects the touch panel body 11, and a base film 31 in which a printed layer 35 is formed instead of the cover glass 21. In the first embodiment, the base film 31 is composed of a single-sided adhesive tape (sometimes simply referred to as a single-sided tape) having the first optical transparent adhesive layer 36 formed on one surface. This single-sided tape is attached to the surface of the cover glass 21, and the cover glass 21 and the touch panel body 11 are attached to each other via the second optical transparent adhesive layer 22.

The touch panel body 11 is a capacitive touch panel, and preferably a projected capacitive type that integrates analog values for each grid. The transparent touch panel body 11 is a rigid body mainly composed of a transparent conductive film (ITO film) and transparent glass. On the touch panel body 11, an opaque electrode pattern (not shown) connected to a transparent electrode pattern made of a transparent conductive film is formed on the outer peripheral portion surrounding the center portion of the touch panel body 11.

The cover glass 21 is bonded to the surface of the rigid touch panel body 11. The cover glass 21 is a bare glass on both sides. The glass may be ordinary glass, but is preferably composed of tempered glass. The cover glass 21 has a second optical transparent adhesive layer 22 formed on the back surface thereof. The second optical transparent adhesive layer 22 is made of, for example, an OCA tape. The cover glass 21 is bonded to the rigid touch panel body 11 via the OCA tape.

The base film 31 is affixed to the surface of the cover glass 21. The base film 31 is a base film for forming the printing layer 35 instead of the cover glass 21. Although this base film 31 can be a base film dedicated to printing, in the present embodiment, a base film for preventing glass scattering is used. The base film for preventing glass scattering is usually adhered to the cover glass surface in order to prevent the cover glass 21 from scattering when it is broken. The base film 31 is made of a transparent plastic resin, for example, an optical polyester film (optical PET film).

A printed layer (design) 35 for concealing the electrode pattern of the touch panel body 11 described above is formed on one surface (back surface) 32 of the base film 31. The print layer 35 is formed on the outer periphery of the one surface 32 of the base film 31 so as to surround the central screen display unit. The print layer 35 may be formed by silk screen printing, but may be formed by gravure printing capable of multiple colors or other printing methods. The thickness of the printing layer 35 is 10 μm or more and 40 μm or less, although it varies depending on the color used.

The other surface 33 opposite to the one surface 32 of the base film 31 on which the printing layer 35 is formed may be a base film basic surface, but it is preferable to form a hard coat layer as necessary. In the example of illustration, the case where the hard-coat layer 34 is formed is shown. The hard coat layer 34 may be made of, for example, an acrylic resin having a pencil hardness of 3H or more.

The first optical transparent adhesive layer 36 is the one surface 32 on which the printing layer 35 is formed, and is formed on the entire surface. For the first optical transparent adhesive layer 36, an adhesive having optical transparency, for example, an acrylic adhesive, a polyurethane adhesive, a polyester adhesive, a rubber adhesive, a silicone adhesive, or the like can be used. . Among these, acrylic pressure-sensitive adhesives are particularly preferable because of easy control of adhesive strength and shear storage elastic modulus. The first optical transparent adhesive layer 36 is in a gel form. In addition, the second optical transparent adhesive layer 22 formed on the entire back surface of the cover glass 21 is also gel-like, and the touch panel cover glass 20 and the touch panel body 11 are connected via the second optical transparent adhesive layer 22. It is pasted together.

Since the first optical transparent adhesive layer 36 is formed so as to absorb the level difference of the printing layer 35, it is preferably larger than the thickness of the printing layer 35 and has a thickness of 20 μm to 50 μm.

The touch panel print film 30 is composed of the base film 31, the print layer 35, and the first optical transparent adhesive layer 36 described above. Moreover, the cover glass 21 for touch panels is comprised by adding the cover glass 21 and the 2nd optically transparent adhesion layer 22 to this printing film 30 for touch panels. The touch panel 10 is obtained by adding a touch panel body 11 to a touch panel cover glass 20.

According to such a configuration, instead of printing directly on the cover glass, indirect printing is performed on the cover glass by laminating a print film, so that the touch panel cover glass can be obtained at low cost. For example, the price can be reduced by 50%. Moreover, since the printing layer 35 is formed on the base film 31 to be attached to the cover glass 21 instead of the cover glass 21 that can only be silk-printed, the printing layer 35 can be formed thin by gravure printing, and the color added to the printing layer 35 It becomes possible. Moreover, since the printing level | step difference was formed in the other surface opposite to the bonding surface with the touchscreen main body 11, the cover glass 21 and the touchscreen main body 11 can be bonded together by the raw surfaces without a level | step difference.

<Manufacturing method of touch panel>
Next, a method for manufacturing the touch panel according to the first embodiment will be described.
In order to manufacture a touch panel, it is necessary to bond a cover glass to the touch panel and to bond a print film for the touch panel to the cover glass. Here, the large-sized base film which can be wound up in roll shape is used for this printing film for touch panels. FIG. 9 shows a large format base film 130. In this large

format base film

130, 17 is a screen display area, 35a is a printing frame, and 35b is a design such as an icon. As shown in FIG. 9, a large number of printed layers (designs) 35 are formed on the entire surface of the large-format substrate film 130, and an adhesive is applied to the entire surface of the entire surface including the printed layer 35. Cured). That is, a liquid adhesive is applied, and the applied liquid adhesive is then cured into a gel. After coating and curing, the large-format base film 130 is cut one by one along the outline of the printing layer 35 and attached to the touch panel body. The outline of the printing layer 35 is shaped to match the bonding portion of the touch panel body. In addition, you may comprise a base film not in a roll-shaped large format base film but in the sheet unit of one leaf. Therefore, hereinafter, the base film means a roll-shaped large base film or sheet.

Referring to FIG. 1, a process for bonding a touch panel and a cover glass, which is one process of a touch panel manufacturing process, will be described.

First, an optical PET film is prepared as the base film 31 (FIG. 1A). The thickness of the base film 31 is, for example, 50 μm or more and 250 μm or less. If necessary, a hard coat layer 34 is formed on the surface of the base film 31 to protect the base film from being damaged. The thickness of the hard coat layer 34 is 4 μm or more and 10 μm or less. In a type in which a glass scattering prevention film is attached to the surface of the cover glass, the base film (optical PET film) 31 is also used as a glass scattering prevention film. A printing layer (see FIGS. 5 and 9) 35 is formed on one surface 32, which is the back surface of the base film 31, by printing, for example, silk screen printing (FIG. 1B). The thickness of the printing layer 35 is 3 μm or more and 30 μm or less, preferably 3 μm or more and 15 μm or less.

Next, a transparent adhesive for bonding the base film 31 to the cover glass 21 (see FIGS. 5 and 1F) is applied to the entire surface 32 of the base film 31 on which the printing layer 35 is formed. Work. This coating is composed of two steps of application and drying.

In the application step, a transparent liquid transparent adhesive composition 36a is applied to the base film 31 (FIG. 1 (c)). At this time, the liquid optical transparent adhesive composition is liquid. Further, the coating conditions are normal temperature, and the atmosphere may be either vacuum or air. Regardless of whether the coating conditions are in a vacuum or in the air, the printing step 35 absorbs the printing step formed between the substrate film one surface 32 and bubbles are generated in the printing step portion regardless of whether the coating condition is in a vacuum or in the atmosphere. Does not occur. In order to prevent bubbles from being generated at the printing step portion, the viscosity of the pressure-sensitive adhesive is preferably in the range of 1000 cps to 10,000 cps.

In the drying step, the applied transparent liquid transparent adhesive composition 36a is dried and cured into a gel to form the first optical transparent adhesive layer 36 (FIG. 1 (d)). The surface (surface opposite to the base film 31) of the formed first optical transparent adhesive layer 36 is a flat surface without steps or irregularities. Since the first optical transparent adhesive layer 36 is thick and has a low hardness, the touch sensation is impaired. Therefore, the required thickness is 10 μm or more and 15 μm or less, and the curing degree is effective 20 degrees or more and 60 degrees or less. And preferably has a curing degree of 45 degrees or more. This degree of cure is comparable to that of gel-like OCA. After forming the first optical transparent adhesive layer 36, a liner 37 is attached to the optical transparent adhesive layer 36 as necessary (FIG. 1E). Thereby, the printing film 30 for touch panels is produced.

Next, the touch-panel printing film 30 on which the first optical transparent adhesive layer 36 is formed is die-cut into a shape that matches the bonded portion of the cover glass 21. After die cutting, the liner 37 is peeled off to expose the first optical transparent adhesive layer 36, and the touch panel print film 30 is attached to the surface (raw surface) of the cover glass 21 through the first optical transparent adhesive layer 36. (FIG. 1 (f)). Here, the pasting method includes not only pasting in the air but also pasting in a vacuum. The cover glass 21 is cut into a shape that matches the bonding portion of the touch panel body 11. The cover glass 21 has a thickness of 550 μm or more and 800 μm or less, and the industry standard thickness is 550 μm.

The cover glass 21 is prepared by pasting the second optical transparent adhesive layer 22 in advance on the back surface thereof. Since the back surface of the cover glass 21 is a bare surface without a step, and the second optical transparent adhesive layer 22 does not need to absorb the step, an OCA tape is attached here as the second optical transparent adhesive layer. The OCA tape has only an optical transparent adhesive layer without an intermediate layer. The thickness of the OCA as the second optical transparent adhesive layer 22 is, for example, 25 μm or more and 350 μm or less, preferably 50 μm or more and 175 μm or less. A liner 23 is attached to the OCA as necessary. The cover glass 20 for touch panels is produced by the process described above.

Finally, the liner 23 on the back surface of the cover glass 20 for the touch panel is peeled to expose the second optical transparent adhesive layer 22, and the touch panel body 11 is attached via the second optical transparent adhesive layer 22 (FIG. 1 ( g)). The touch panel body 11 is a projection capacitive type. Its thickness is not less than 550 μm and not more than 800 μm, and the industry standard thickness is 550 μm. Thereby, the touch panel 10 is completed. The completed touch panel 10 is formed by bonding a cover glass (rigid body) 21 and a touch panel body 11 (rigid body). However, there is a printing step on the touch-panel printing film 30 interposed between the cover glass 21 and the touch panel body 11. Since it is made to absorb, a bubble does not generate | occur | produce in a printing level | step-difference part, but an adhesive failure does not arise.

<Effect of the first embodiment>
(1) According to this embodiment, since the printing layer 35 is printed on the base film (optical PET film) 31 with less printing restrictions compared to glass, compared with the case of printing on the rigid cover glass 21. It can be printed thinly and inexpensively. In addition, since the liquid transparent adhesive composition 36a is applied to the one surface 32 of the base film 31 on which the printing layer 35 is formed to absorb the printing step, the gel is cured and then bonded to the cover glass. Compared with the case where the OCA tape is directly attached to the cover glass, the printing step can be easily absorbed by the thin layer, and adhesion failure such as peeling and foaming can be greatly reduced when the attachment is performed. The present embodiment absorbs a printing step when the pressure-sensitive adhesive is liquid, and therefore has a great advantage because the printing step can be easily absorbed particularly when the printing step such as silk screen printing is large.
(2) Further, according to the present embodiment, the liquid adhesive that absorbs the printing step is cured into a gel to form a transparent optical adhesive layer having a flat surface. Therefore, it is not necessary to pay attention to the generation of bubbles, and it is easy to bond the cover glass. In addition, the bonding may be performed in a vacuum, but may be performed in the air, so that the bonding of the cover glass becomes easier.
(3) Moreover, since the liquid transparent adhesive composition 36a is cured to form a gel-like transparent adhesive layer for optics 36, the touch-panel printing film 30 is die-cut, so that the liquid transparent adhesive composition 36a is bonded in a liquid state like a UV curable resin. Compared to the case, the adhesive does not protrude when being bonded to the cover glass 21. Therefore, the yield of bonding is good.

(4) In particular, in a type in which a glass scattering prevention base film is pasted on the cover glass surface, the touch panel printing film 30 also serves as a glass scattering prevention film by bonding the touch panel printing film 30 to the cover glass. Therefore, it is possible to prevent the cost of the touch panel 10 from increasing.

(5) Since the printing layer 35 is formed on the base film 31, unlike the case where it is formed on the cover glass 21, a large number of printing layers 35 (designs) can be taken on the roll-shaped large base film 130. .

(6) Moreover, since the touch-panel printing film 30 also serves as an anti-scattering film, it is possible to prevent fragments from being scattered when the cover glass 21 is broken.

It should be noted that not all the combinations of features described in the above-described embodiments, modifications, and illustrated examples are essential to the means for solving the problems of the present invention. Needless to say, various modifications can be made without departing from the technical idea of the present invention. For example, in the above-described embodiment, the single-sided adhesive base film is attached to the cover glass, but a double-sided adhesive base film may be attached. Below, the case where this double-sided adhesive base film is used is demonstrated.

[Second Embodiment]
The second embodiment is structurally different from the first embodiment in that the touch-panel print film is a double-sided adhesive tape (sometimes simply referred to as a double-sided tape), and the cover glass is sandwiched between the double-sided tape and the cover glass. This is the point where the touch panel body is attached. Also in 2nd Embodiment, the printing film for touchscreens serves as a glass scattering prevention base film. The glass scattering prevention base film may be attached not only to the front surface of the cover glass but also to the back surface. 2nd Embodiment utilizes the glass scattering prevention base film affixed on this back surface.

In the manufacturing method of the touch-panel print film to be attached to the cover glass that protects the rigid touch panel body according to the present embodiment, a step of forming a frame-shaped print layer on one surface of the base film to be attached to the cover glass; A step of applying a transparent liquid transparent adhesive composition for laminating the cover glass on the entire surface of the base film on which a printed layer is formed; and the liquid transparent adhesive composition applied on the entire surface of the base film. Forming a first optical transparent adhesive layer by curing the product in a gel state, and forming a second optical transparent adhesive layer on the entire other surface opposite to the substrate film on which the printed layer is not formed And a step of performing. When the liquid transparent adhesive composition is applied, the step of the printed layer formed on the base film is easily absorbed. Therefore, when a base film having a printed step is bonded to the cover glass, peeling or foaming is unlikely to occur.

Moreover, in the manufacturing method of the cover glass for touchscreens by this Embodiment, the cover glass obtained by the manufacturing method of the printing film for touchscreens mentioned above is made into the said cover glass through the said 1st optically transparent adhesive layer. I'm trying to paste it on one side. Since the base film is attached to the cover glass after the pressure-sensitive adhesive is cured in a gel form to form the first transparent adhesive layer for optics, adhesion failure due to peeling or foaming hardly occurs. Moreover, since it sticks after hardening an adhesive in gel form, an adhesive does not protrude easily.

In the touch panel manufacturing method according to the present embodiment, the touch panel cover glass obtained by the touch panel cover glass manufacturing method described above is attached to the touch panel body via the touch panel print film. . The other surface opposite to the one surface of the touch panel print film is originally flat and has no step, and even when directly attached to the touch panel body via the second optical transparent adhesive layer, adhesion failure due to peeling or foaming is unlikely to occur. . Therefore, adhesion failure between the cover glass and the touch panel can be eliminated. In addition, since the cover glass and the touch panel body are directly pasted via the touch panel printing film, the touch panel can be made thinner.

Hereinafter, the second embodiment will be specifically described with reference to FIG.

<Configuration of touch panel>
As shown in FIG. 6, the 1st optical transparent adhesion layer 36 is formed in the whole surface 32 in which the printing layer 35 of the printing film 30 for touchscreens was provided. An optical transparent adhesive layer 38 is formed on the entire other surface 33 opposite to the hard coat layer 34 of the touch panel print film 30. In the present embodiment, since the touch panel print film 30 is sandwiched between the cover glass 21 and the touch panel body 11 (FIG. 2G), the touch panel print film 30 is exposed to the outside. Unlike the embodiment, the hard coat layer 34 is unnecessary. However, when the substrate film in the process shown in FIG. 2 (d) is handled as a printed film product for touch panels, the surface is protected so that the substrate film (optical PET film) 31 is not damaged during the handling. Therefore, a hard coat layer 34 is required.

The cover glass 21 and the touch panel body 11 are bonded to each other via the touch panel printing film 30. In this case, even if the first optical transparent adhesive layer 36 of the touch panel print film 30 is attached to the cover glass 21 and the optical transparent adhesive layer 38 is attached to the touch panel body 11, the touch panel print film 30 is turned upside down. Alternatively, the optical transparent adhesive layer 38 may be attached to the cover glass 21 and the first optical transparent adhesive layer 36 may be attached to the touch panel body 11.

According to such a configuration, since the cover glass 21 and the touch panel body 11 are directly pasted via the touch panel printing film 30, the touch panel 10 can be thinned.

<Manufacturing method>
In the description of the manufacturing method of the second embodiment, the description of the same steps as those of the first embodiment is omitted.

As shown in FIG. 2, until the first optical transparent adhesive layer 36 is formed by coating on the entire surface 32 of the base film 31 on which the printing layer 35 is formed (FIGS. 2A to 2D). Is the same as in the first embodiment. Thereafter, a liner 37 is attached to the first optical transparent adhesive layer 36, and an optical transparent adhesive layer 38 is formed on the entire other surface 33 opposite to the hard coat layer 34 of the base film 31. (FIG. 2 (e)). The optical transparent adhesive layer 38 may be formed by coating in the same manner as the first optical transparent adhesive layer 36, but the other surface 33 is a base film surface without a step and does not need to absorb the step. Therefore, an OCA tape is attached here. Therefore, pasting becomes easier.

A liner 39 is attached to the optical transparent adhesive layer 38 made of OCA tape to produce a touch panel print film 30 (FIG. 2G). The touch-panel printing film 30 is die-cut into a shape that matches the cover glass 21 and the bonded portion of the touch panel body 11. After die-cutting, one liner 37 is peeled off to expose the first optical transparent adhesive layer 36, and the touch panel print film 30 is placed on the back surface (raw surface) of the cover glass 21 through the first optical transparent adhesive layer 36. paste. Thereby, the cover glass 20 for touch panels is produced. Further, the other liner 39 is peeled off to expose the optical transparent adhesive layer 38, and the touch panel print film 30 is attached to the surface (raw surface) of the touch panel body 11 through the optical transparent adhesive layer 38. Thereby, the touch panel 10 is produced (FIG. 2F).

<Effects of Second Embodiment>
According to the second embodiment, in addition to the effects of the first embodiment, the cover glass 21 and the touch panel body 11 are directly pasted via the touch-panel print film 30. Compared with the first embodiment that requires a dedicated optical transparent adhesive layer for bonding to the touch panel, the touch panel 10 can be made thinner.

In the second embodiment described above, an optical transparent adhesive layer is not formed on the cover glass 21 side and the touch panel body 11 side, and the first and second optical transparent layers are formed only on both surfaces of the touch panel print film 30. Adhesive layers 36 and 38 are formed, and the cover glass 21 and the touch panel body 11 are bonded to each other through the double-sided tape. However, the present invention is not limited to this. For example, in FIG. 2G, an optical transparent adhesive layer is also formed on the cover glass 21 side and the touch panel body 11 side, respectively, and the cover glass 21, the touch panel print film 30, and the optical transparent adhesive on the touch panel body 11 are formed. The cover glass 21 and the touch panel body 11 may be bonded together by bringing the layers into close contact with each other. This further facilitates the bonding operation. As described above, the optical transparent adhesive layer is formed not only on one of the objects to be bonded (the cover glass, the touch panel main body, or the touch panel print film), but is formed on both sides, and the first embodiment and This is also common to the second embodiment.

In the above-described second embodiment, the case where the touch panel print film 30 is a double-sided tape has been described, but a single-sided tape may be used. For example, in FIG. 2G, the optical transparent adhesive layer 38 is formed not on the touch panel print film 30 side but on the surface side of the touch panel main body 11, and the touch panel main body 11 is touched with the optical transparent adhesive layer 38. The printing film 30 is pasted. In this case, it is possible to use the touch-panel print film 30 of the first embodiment, which is also composed of a single-sided tape, as the touch-panel print film 30 composed of a single-sided tape.

[Third Embodiment]
The third embodiment is a modification of the second embodiment. The third embodiment is structurally different from the second embodiment in that the center portion of the touch panel print film is punched out and filled with an adhesive.

Hereinafter, the third embodiment will be specifically described with reference to FIG.

<Configuration>
As shown in FIG. 7, the touch panel print film 30 has a window 40 formed in the center, and the window 40 is filled with a transparent optical transparent adhesive layer 38. That is, the touch-panel print film 30 leaves a circumferential print layer 35, a base film portion 31a on which the print layer 35 is formed, and a first optical transparent adhesive layer 36 formed below the base film portion. Thus, the central portion is punched to form the window 40. The transparent adhesive layer for optics 38 on the other side opposite to the printed layer 35 of the remaining base film part 31a in the window 40 is filled and formed.

According to such a configuration, the window 40 is opened at the center of the touch-panel print film 30 interposed between the cover glass 21 and the touch panel body 11, and the transparent optical transparent adhesive layer 38 is further formed in the window 40. Therefore, the visibility due to light reflection / refraction can be improved as compared with the case where the optical base film 31 is present in the central portion. Moreover, according to such a structure, since it can adhere | attach on the opposite surface whole surface of the printing film 30 for touchscreens, a window is opened in the center part of a base film, and it is used as an air layer only around the base film opposite surface. Compared with those that adhere, the strength characteristics are improved.

<Manufacturing method>
As shown in FIG. 3, first, an optical substrate film 31 is prepared (FIG. 3A). In the present embodiment, the central portion of the optical base film 31 is punched out, and the hard coat layer cannot perform its function, and thus is not formed on the optical base film 31. A print layer 35 is formed on the entire surface 32 of the optical base film 31 by printing, for example, gravure printing (FIG. 1B).

Next, a gel-like first optical transparent adhesive layer 36 is formed on the entire surface 32 of the optical substrate film 31 on which the printed layer 35 is formed (FIG. 1C).

Thereafter, the optical base film 31 on which the first optical transparent adhesive layer 36 is formed leaves the printed layer 35 in a frame shape, and the central portion thereof is punched out together with the first optical transparent adhesive layer 36 to open the window. 40 is formed (FIG. 3D). A liner 39 is attached to one surface of the base film portion 31a left in the frame shape via the first optical transparent adhesive layer 36 (FIG. 3E).

A transparent liquid transparent adhesive composition is applied to the surface of the base film portion 31a left in the frame shape on the printed layer 35 side so that the inside of the window 40 formed by punching the optical base film 31 is filled. To do. Even in this application, the liquid transparent adhesive composition overflowing from the window 40 covers the surface of the base film portion 31a remaining in a circumferential shape, so the first optical transparent adhesive layer 36, the base film portion 31a, and the printing layer 35 are covered. The laminated window step consisting of is easily absorbed. After the application, the transparent liquid transparent adhesive composition is dried and cured into a gel to form an optical transparent adhesive layer 38 (FIG. 3 (f)). After the optical transparent adhesive layer is formed, a liner 37 is attached to the optical transparent adhesive layer 38 of the base film portion 31a as required (FIG. 3G). Thereby, the printing film 30 for touch panels is produced.

The touch-panel printing film 30 is die-cut into a shape that matches the cover glass 21 and the bonded portion of the touch panel body 11. After die cutting, one of the liners 37 is peeled off to expose the optical transparent adhesive layer 38, and the touch panel print film 30 is attached to the back surface (raw surface) of the cover glass 21 through the optical transparent adhesive layer 38. Thereby, the cover glass 20 for touch panels is produced. Further, the other liner 39 is peeled off to expose the first and second optical transparent

adhesive layers

36 and 38, and the surface of the touch panel body 11 is interposed via the first and second optical transparent

adhesive layers

36 and 38. The cover glass 20 for touch panels is affixed on (raw surface). Thereby, the touch panel 10 is produced (FIG. 3H).

In the above-described embodiment, the printing layer 35 is formed on one surface of the optical base film 31 and the gel-like first optical transparent adhesive layer 36 is formed on the opposite surface (FIG. 3C). ), The first optical transparent adhesive layer 36 may be formed on the print layer 35. In this case, the stacking order of the first optical transparent adhesive layer 36, the base film portion 31a, and the printing layer 35 is changed, but if the steps (d) to (h) shown in FIG. A touch panel equivalent to that shown in FIG.

In the above-described embodiment, when the touch panel body 11 is seen through from the cover glass 21 side, the orientation of the touch-panel print film 30 is set so that the boundary between the first and second optical transparent

adhesive layers

36 and 38 cannot be seen. Consideration. That is, the optical transparent adhesive layer 38 of the touch panel print film 30 is bonded to the cover glass 21 with the surface of the optical transparent adhesive layer 38 formed on the entire surface, and the first optical transparent adhesive layer 36 is provided at the outer peripheral portion and the optical portion at the central portion. A transparent adhesive layer 38 is separately formed and bonded to the touch panel body with the back side where the boundary is visible facing down. Therefore, the obtained touch panel has no optical discomfort. The cover glass 21 and the touch panel body 11 may be bonded to each other with the front and back surfaces of the touch panel print film 30 reversed, in which case the first and second optical transparent adhesive layers 36 through the cover glass 21, Since 38 boundaries can be seen, an optical discomfort is generated.

<Effect of the third embodiment>
In addition to the effects of the second embodiment, since the transparent optical transparent adhesive layer 38 is present in the center of the base film between the cover glass 21 and the touch panel body 11, the optical base film 31 is present. Visibility by reflection / refraction of light can be improved as compared with the above. In addition, since the window 40 is opened in the center of the touch panel print film to form an air layer, it can be bonded to the entire opposite surface compared to the case where only the periphery of the opposite surface of the substrate film is bonded, so that it is strong. Improved characteristics.

Further, since the liquid adhesive is poured into the window 40 at the center of the base film, the step difference in the laminated window composed of the base film part, the printing layer 35 and the first optical transparent adhesive layer 36 can be easily absorbed. Therefore, it is possible to effectively prevent the generation of bubbles at the stepped portion, greatly reduce the adhesion failure with the cover glass 21, and improve the productivity of the touch panel.

Moreover, since the surface where the boundary of the 1st and 2nd optical transparent

adhesive layers

36 and 38 of the touch-panel printing film 30 cannot be seen is bonded to the cover glass, the first and second optical transparent adhesives are attached. Optical discomfort caused by layer boundaries can be eliminated.

[Fourth Embodiment]
By the way, in the touch panel print film of the first to third embodiments described above, the base film 31 is a constituent element of the touch panel print film, so that the thickness is increased by the thickness of the base film 31. Further, the transmittance of the printing film 30 decreases depending on the thickness of the printing film 30. Therefore, there is room for improvement in thickness when the printing film 30 is thinned.

Therefore, in the fourth embodiment, the base film can be peeled off, and an absorption layer that absorbs the thickness of the printing layer is formed on one surface of the base film with a non-adhesive optical transparent resin layer. After the first optical transparent adhesive layer is provided on the optical transparent resin layer, the second optical transparent is formed on the exposed surface of the printed layer and the optical transparent resin layer exposed by peeling and removing the base film. An adhesive layer is provided. By comprising in this way, the printing film for touchscreens which is thinner and has high transmittance can be obtained.

<Configuration>
Next, a fourth embodiment of the touch-panel printed film will be specifically described with reference to FIG. FIG. 8 is a cross-sectional view of the touch panel according to the fourth embodiment.

The touch panel print film 30 includes a gel-like second optical transparent adhesive layer 22, a frame-shaped print layer 35 provided on the second optical transparent adhesive layer 22, and the surface of the print layer 35. Optically formed by applying a liquid curable optical transparent resin composition over one surface of the second optical transparent adhesive layer 22 in the frame of the print layer 35 and curing the surface so that the surface becomes flat. A transparent resin layer 42 and a first optical transparent adhesive layer 36 provided on the optical transparent resin layer 42 are provided. A cover glass 21 is bonded to the touch panel print film 30 via a second optical transparent adhesive layer 22 to form a touch panel cover glass 20. A sensor glass as the touch panel body 11 is bonded to the touch panel cover glass 20 via the first optical transparent adhesive layer 36 to constitute the touch panel 10.

Although not shown in FIG. 8, a base film to be peeled and removed is required to configure the touch panel print film 30 having the laminated structure as described above. That is, the touch-panel print film 30 is an optically transparent resin layer (for example, an acrylic resin layer) 42 that is cured on a peelable substrate film to a print layer 35 and a hardness exceeding the gel hardness (for example, 100%). , And a gel-like first optical transparent adhesive layer 36 are laminated in this order. The curable optical transparent resin layer 42 is formed by curing a liquid curable optical transparent resin composition on the base film and the printing layer 35. Further, after the first optical transparent adhesive layer is laminated, the base film is peeled and removed, and the second optical transparent adhesive layer 22 is laminated on the exposed optical transparent resin layer 42 and the printed layer 35. . *

Since the optical transparent resin layer 42 is formed so as to absorb the level difference of the printing layer 35, it is preferably larger than the thickness of the printing layer 35 and has a thickness of 20 μm or more and 50 μm or less.

The transparent resin composition constituting the transparent resin layer 42 is not particularly limited as long as it is a resin having transparency, olefin resins such as polyethylene and polypropylene, diene resins such as polybutadiene and polyisoprene, polyacrylic acid, poly Examples thereof include acrylic resins such as acrylic acid ester, polymethacrylic acid, and polymethacrylic acid ester, polyvinyl esters such as polyvinyl acetate, polyvinyl alcohol derivatives such as polyvinyl alcohol and polyvinyl butyral, polystyrene, and polyacrylonitrile. Among these, an acrylic resin is preferable from the viewpoint of transparency and strength. In addition, when forming the hard-coat layer 15 on the mold release layer 16a of the base film 16, it is preferable to comprise this hard-coat agent from the said transparent resin composition, especially an acrylic resin. When the transparent resin composition contains an acrylic resin, the transparency of the transparent resin layer is further improved, and the transparency of the printing film is improved.

<Manufacturing method>
Next, the manufacturing method of the touchscreen print film concerning 4th Embodiment is demonstrated.

The manufacturing method of the printing film for touch panels is demonstrated using FIG.
The manufacturing method of the printing film for touchscreens of this embodiment is the process of forming the frame-shaped printing layer 35 on one surface of the peelable base film 16, and the printing layer 35 of the base film 16 is formed. A step of applying a liquid optical transparent resin composition on the surface to absorb a step due to the thickness of the printing layer 35, and curing the liquid transparent resin composition to form the optical transparent resin layer 42. After the step, the step of forming the first optical transparent adhesive layer 36 on the optical transparent resin layer 42, and the step of forming the first optical transparent adhesive layer 36, the printed layer 35 and the optical transparent resin layer 42 A step of peeling and removing the base film 16 from the step, and a step of forming the second optical transparent adhesive layer 22 on the surfaces of the print layer 35 and the optical transparent resin layer 42 exposed by peeling and removing the base film 16. ,including.

First, a peelable substrate film 16 serving as a carrier is prepared (FIG. 4A). The base film 16 has a thickness of, for example, 25 μm or more and 50 μm or less. A release treatment is performed on one surface of the base film 16 to form a release layer 16a having a thickness of 1 μm to 2 μm (FIG. 4B). Examples of the release treatment agent include a silicone release treatment agent, a fluorine release treatment agent, and a long-chain alkyl release treatment agent. Among them, a silicone release treatment agent is preferable, and a curing is performed. As a method, it is preferable to use a curing method such as ultraviolet irradiation or electron beam irradiation. A hard coat layer may be formed on the release layer 16 a of the base film 16. When the hard coat layer is formed, the thickness is preferably 4 μm or more and 10 μm or less.

A frame-shaped print layer 35 is formed on the formed release layer 16a by printing, for example, gravure printing or screen printing (FIG. 4C). The thickness of the print layer 35 is 5 μm or more and 40 μm or less, although it varies depending on the color.

A liquid optical transparent resin composition is applied on the release layer 16a on which the printing layer 35 is formed so as to absorb the level difference due to the thickness of the printing layer 35, and this resin composition is cured to optically. A transparent resin layer 42 is formed (FIG. 4D). By applying the liquid optical transparent resin composition, it is absorbed by the step due to the thickness of the printing layer 35, and bubbles are hardly generated.

The optical transparent resin layer 42 has a thickness of 20 μm or more and 50 μm or less, depending on the thickness of the printing layer 35. The optical transparent resin layer 42 and the print layer 35 are flat on the surface of the release layer 16a. The surface of the optical transparent resin layer 42 on which the first optical transparent adhesive layer 36 is formed becomes flat because the steps of the printing layer 35 are absorbed, but depending on the viscosity of the optical transparent resin composition, There may be a case where a minute depression due to the printing layer 35 is generated. For this reason, it is preferable to make the viscosity of a transparent resin composition into the range of 1000 cps or more and 10,000 cps or less. The optical transparent resin composition is cured by ultraviolet rays, heat, electron beam, visible light, etc., and is not particularly limited, but preferably a resin composition that is crosslinked and cured by ultraviolet rays, heat, or combination, More preferably, an ultraviolet crosslinking curable resin composition is used.

The first optical transparent adhesive layer 36 is formed on the cured optical transparent resin layer 42. As the first optical transparent adhesive layer 36, a gel-like adhesive layer, for example, an optical transparent adhesive tape (OCA tape) is bonded together (FIG. 4E). In the OCA tape, a liner 23 as a protective layer is bonded to the first optical transparent adhesive layer 36. When the first optical transparent adhesive layer 36 is formed, the surface of the optical transparent resin layer 42 is flat, so that the thickness of the first optical transparent adhesive layer 36 is thin, for example, 25 μm or more and 50 μm or less. it can.

Subsequently, the base film 16 is peeled and removed together with the release layer 16a to obtain a printed film for a touch panel in which the first optical transparent adhesive layer 36 is formed and the adhesive surface is on one side (FIG. 4 (f)). ). After the substrate film 16 is peeled and removed, the second optical transparent adhesive layer 22 is bonded onto the exposed surfaces of the transparent resin layer 42 and the print layer 35 exposed by peeling, and the adhesive film has a double-sided adhesive film. 30 is obtained (FIG. 4 (g)). The thickness of the second optical transparent adhesive layer 22 can be the same as that of the first optical transparent adhesive layer 36.

<Effect of the fourth embodiment>
According to this, since the base film is peeled and removed from the touch panel print film 30, the touch panel print film 30 can be thinned. Further, when an optical transparent resin cured to a hardness exceeding the gel state is used, the strength can be sufficiently maintained even if the base film is peeled and removed. For this reason, there is no possibility that the optical transparent adhesive layer 42 in the frame of the printing layer 35 is recessed in the antigravity direction even when the liner or the base film is peeled off, as in the case of using the gel-like optical adhesive layer. . This is particularly effective when the area within the frame becomes large. Moreover, when an acrylic resin is used for the transparent resin layer for optics, the transparency of the print film 30 for touch panels can further be improved.

In the above-described fourth embodiment, after the base film 16 is peeled and removed, the second optical transparent adhesive layer 22 is pasted on the surfaces of the print layer 35 and the optical transparent resin layer 42 exposed by the peeling. I try to match. However, the second optical transparent adhesive layer 22 may be bonded in advance before the base film 16 is peeled and removed. That is, the second optical transparent adhesive layer 22 is formed on the release layer 16a formed on the base film 16, the hard coat layer 34 is formed on the second optical transparent adhesive layer 22, and the hard coat layer A printing layer 35 and an optical transparent resin layer 42 are formed on 34. According to this, the printing film 30 for double-sided touch panels is obtained only by peeling and removing the base film 16.

Next, an example in which the touch panel print film of the present embodiment is applied to a touch panel of a display device of a multifunction terminal will be described. Here, the on-cell glass refers to a type of touch panel in which a cover glass is disposed on the sensor glass, and the one glass refers to a type of touch panel in which the cover glass is integrated with the sensor glass. Moreover, the printed film for touch panels illustrated showed the form supplied from the film maker. A touch panel manufacturer assembles a touch panel or a display device using the touch panel printing film of this embodiment. Furthermore, this example evaluated the thickness of the printing film for touch panels, the cover glass for touch panels, and the touch panel mainly with the comparative example.

[Example 1]
Example 1 is shown in FIG. Example 1 is an on-cell glass type touch panel, and the touch-panel printing film 30 of the type shown in FIG. 6 is applied to the OCA tape as the optical transparent adhesive layer 26 that bonds the cover glass 21 and the touch panel body 11 together. It is what. As shown in FIG. 10, the display device includes an LCD panel 12, a sensor glass as a projected capacitive touch panel body 11, a cover glass 21, and an optical for attaching the sensor glass to the LCD panel 12. The OCA tape as the transparent adhesive layer 38, the optical transparent adhesive layer 26 for bonding the cover glass 21 and the sensor glass, and the scattering prevention film 13 for protecting the surface of the cover glass 21 were used.

The thickness of the scattering prevention film 13 was 120 μm, the thickness of the cover glass 21 was 550 μm, and the thickness of the sensor glass was 550 μm. Further, the optical transparent adhesive layer 26 for bonding the cover glass 21 to the sensor glass was thinned to 125 μm so as not to impair the touch feeling. The OCA tape as the optical transparent adhesive layer 38 for bonding the sensor glass to the LCD panel 12 is made thicker than the optical transparent adhesive layer 26 so that the adhesive force is not impaired. Was 175 μm. When the thickness of the OCA tape is 250 μm, the existing transparent UV curing adhesive may be used for the optical transparent adhesive layer 38 instead of the OCA tape.

The touch-panel print film 30 applied to the optical transparent adhesive layer 26 includes an optical PET film as the base film 31 having a thickness of 95 μm, and the touch-panel print film 30 formed on the surface of the base film 31 with the cover glass 21. The OCA tape as the second optical transparent adhesive layer 22 having a thickness of 15 μm to be attached to the substrate, the closed loop-shaped printing layer 35 having a gravure printed on the back surface of the optical PET film, and a touch panel on the sensor glass And OCA as the first optical transparent adhesive layer 36 having a thickness of 15 μm for attaching the printing film 30 for printing.

Since the printing layer 35 is printed on the film surface instead of the glass surface, the color is black by gravure printing, and the light shielding property can be ensured. The OCA as the first optical transparent adhesive layer 36 is not a gel-like OCA tape from the beginning, but is made liquid to absorb the step (thickness) of the printed layer 35, and this liquid adhesive is applied. Later, it was cured into a gel to obtain OCA.

According to Example 1, a 125 μm thick touch panel printed film, a 795 μm thick touch panel cover glass, and a 1345 μm thick touch panel were obtained.

[Example 2]
Example 2 is shown in FIG. The difference from Example 1 is that a touch panel print film 30 of the type shown in FIG. 7 is adopted for the touch panel print film. The optical transparent adhesive layer 26 for bonding the cover glass 21 and the sensor glass to a thickness of 125 μm was composed of the touch panel print film 30 described above. This touch-panel print film 30 is formed on the surface of the optical PET film portion as the 95 μm-thick base film portion 31 a and the optical PET film portion, and is used to affix the touch-panel print film 30 to the cover glass 21. OCA tape as the first optical transparent adhesive layer 36 having a thickness of 15 μm, a printing layer 35 having a thickness of 10 μm gravure-printed on the back surface of the optical PET film portion, and a printed film for a touch panel on the cover glass 21 and the sensor glass It was comprised from OCA as the transparent adhesive layer 38 for optics with a thickness of 125 micrometers for affixing 30. FIG.

In Example 2, as in Example 1, a 125 μm thick touch panel print film, a 795 μm thick touch panel cover glass, and a 1345 μm thick touch panel were obtained.

[Comparative Example 1]
In the touch panel of Comparative Example 1, an OCA tape having a thickness of 175 μm was used as it is as the optical transparent adhesive layer 26 instead of using the touch panel print film 30 in Example 1 shown in FIG. Further, as the cover glass, a cover glass in which a frame-like BM (black matrix) layer was formed on the back surface was used instead of the cover glass 21 having both surfaces. The other points were the same as those in Example 1. According to this, the thickness of the obtained OCA tape for touch panel is 175 μm, the thickness of the cover glass for touch panel is 845 μm, and the thickness of the touch panel is 1395 μm, both compared with Example 1 and Example 2. It was thick.

[Example 3]
Example 3 is shown in FIG. In Example 3, the touch panel is not the on-cell glass as in Example 1, but the sensor glass as the touch panel body 11 is a one-glass type in which the cover glass is also used. Further, Example 3 is different from Example 1 in that the BM layer 25 is formed on the back surface of the sensor glass, and the touch-panel print film is applied to the optical transparent adhesive layer 38 between the sensor glass and the LCD panel 12. . The touch-panel print film 30 applied to the optical transparent adhesive layer 38 has the same configuration as in Example 1 except for the dimensions.

The sensor glass had a thickness of 550 μm, and a BM layer 25 was formed on the back surface. The BM layer shields the wiring formed on the LCD panel 12 so as to be invisible even when viewed from above, and a black photoresist (black resist) is used. The touch-panel print film 30 applied to the optical transparent adhesive layer 38 had a thickness of 125 μm. This touch panel print film 30 is an optical PET film as a base film 31 having a thickness of 50 μm, and a thickness of 65 μm formed on the surface of the base film 31 for attaching the touch panel print film 30 to the cover glass 21. In order to affix the OCA tape as the second optical transparent adhesive layer 22, the closed loop 10 μm thick print layer 35 that is gravure-printed on the back surface of the optical PET film, and the touch panel print film 30 to the sensor glass. And OCA as the first optical transparent adhesive layer 36 having a thickness of 10 μm.

As described above, the first optical transparent adhesive layer 36 is not a gel-like OCA tape from the beginning, but is liquefied to absorb this pattern printing step (thickness). After the application, OCA was cured in a gel state.

The printing layer has a two-layer structure of a BM layer 25 and a printing layer 35. The BM layer 25 has a black (uncolored) frame shape, and is formed by cutting out a pattern 35b such as an icon, decoration, or logo in a part of the frame (see FIG. 9). The printing layer 35 was colored by gravure printing at a position overlapping the BM layer 25 in the vertical direction. Thereby, the light which permeate | transmits the printing layer 35 by which color printing was carried out was colored, and the design 35b could be colored in arbitrary colors by allowing this colored light to pass through the hollowed-out design 35b. In addition, it turned out that the printing film 30 for touch panels has a function to prevent scattering of the sensor glass by being attached to the back surface of the sensor glass.

In Example 3, a 125 μm thick touch panel print film and a 675 μm thick touch panel were obtained.

[Example 4]
Example 4 is shown in FIG. Example 4 is a one-glass type like Example 3, but differs from Example 3 in that a touch-panel printing film is applied to the anti-scattering film 13 provided on the top of the display device. As shown in FIG. 13, the display device includes an LCD panel 12, a touch panel body 11 made of a projected capacitive sensor glass, and a second optical transparent adhesive layer for attaching the sensor glass to the LCD panel 12. It comprised from the OCA tape as 22 and the scattering prevention film 13 which protects a sensor glass surface.

The second optical transparent adhesive layer 22 made of OCA tape provided between the sensor glass as the touch panel body 11 and the LCD panel 12 has a thickness of 175 μm in order to absorb the step of the BM layer 25. The touch panel body 11 made of sensor glass had a thickness of 550 μm, and a frame-like BM layer 25 was formed on the back surface to be attached to the LCD panel 12. The BM layer 25 shields the wiring formed on the LCD panel 12 so as to be invisible even when viewed from above, and a black photoresist (black resist) is used.

The scattering prevention film 13 had a thickness of 115 μm and was constituted by the above-described touch panel printing film. The scattering prevention film 13 includes a base film 31 made of an optical PET film having a thickness of 95 μm, a hard coat layer 34 made of an acrylic resin having a thickness of 5 μm formed on the surface of the base film 31, and a base film. A printing layer 35 having a thickness of 10 μm printed on the back surface of 31 and a first optical transparent adhesive layer 36 made of OCA having a thickness of 15 μm for attaching the anti-scattering film 13 to the sensor glass.

Since the printing layer 35 is printed on the film surface instead of the glass surface, gravure printing was used instead of uncolored BM formation. The printed layer may be uncolored or colored. In the case of uncolored, for example, black, the light that could not be shielded by the BM layer 25 was further shielded, and the light shielding property could be ensured. In the case of coloring, in addition to the above-mentioned light shielding properties, it was possible to print a pattern such as an icon, a decoration, or a logo. The first optical transparent adhesive layer is not a gel-like OCA tape from the beginning, but is made liquid to absorb the step (thickness) of this pattern printing, and after applying this liquid adhesive, it becomes a gel A cured OCA was obtained.

In Example 4, a 115 μm thick touch panel print film and a 665 μm thick touch panel were obtained. And the thickness which added the OCA tape as the transparent adhesive layer 22 for optical surfaces of this back surface further to this touch panel was 840 micrometers.

[Example 5]
Example 5 is shown in FIG. In Example 5, a printed film for touch panel is applied to the scattering prevention film 13 as in Example 4. The difference from Example 4 in FIG. 13 is that the anti-scattering film 13 is provided in the middle instead of the top of the display device. That is, the scattering prevention film 13 was disposed between the sensor glass as the touch panel body 11 and the OCA tape as the second optical transparent adhesive layer 22. The scattering prevention film 13 had the same laminated structure as that of Example 4, but the direction of the upper and lower surfaces was reversed. The anti-scattering film 13 is attached to the back surface of the touch panel body (sensor glass) 11 with the first optical transparent adhesive layer 36 facing upward, and the second optical transparent adhesive layer with the hard coat layer 34 facing downward. It was affixed to the surface of the LCD panel 12 via 22.

Here, the thickness of the sensor glass was 550 μm, and the thickness of the anti-scattering film 13 was 80 μm. The thickness of the second optical transparent adhesive layer 22 made of an OCA tape was 100 μm. As for the thickness of each layer constituting the scattering prevention film 13, the thickness of the base film 31 made of optical PET film is 60 μm, the thickness of the hard coat layer 34 made of acrylic resin is 5 μm, and the thickness of the printing layer 35 is The thickness of the first optical transparent adhesive layer 36 made of OCA and OCA was 15 μm.

In the fifth embodiment, the vertical arrangement of the printed layer 35 printed on the anti-scattering film 13 and the BM layer 25 printed on the touch panel body (sensor glass) 11 is opposite to that of the first embodiment. For this reason, the printing layer 35 arranged on the lower side can increase or decrease the black transmittance of the BM layer 25 by, for example, red or orange. Moreover, since the scattering prevention film 13 was provided between the touch panel main body 11 made of sensor glass and the LCD panel 12, it was possible to prevent glass scattering of the touch panel main body (sensor glass) 11 and the LCD panel 12.

According to Example 5, a printed film for a touch panel having a thickness of 80 μm and a touch panel having a thickness of 630 μm were obtained. And the thickness which added the OCA tape as the optical transparent adhesion layer 22 of the back surface of the printing film for touchscreens to this touchscreen was 730 micrometers.

[Example 6]
Example 6 is shown in FIG. Example 6 is a combination of Example 4 and Example 5, and uses two

scattering prevention films

13 and 24. As shown in FIG. 15,

anti-scattering films

13 and 24 made of a touch panel printing film were attached to the upper and lower surfaces of the touch panel body 11 made of sensor glass, respectively.

Here, the thickness of the sensor glass was 550 μm, and the thickness of the second optical transparent adhesive layer 22 made of OCA tape was 100 μm. If the thickness of each layer of the upper anti-scattering film 13 and the lower anti-scattering film 24 is set to exactly the same specification, the process can be further simplified and the cost can be reduced. The thickness of the scattering prevention film 13 was 75 μm, and the thickness of the lower scattering prevention film 24 was 50 μm. Note that the hard coat layer 34 of the anti-scattering film 24 disposed on the lower side may be omitted.

Example 6 A touch panel having a thickness of 790 m in which a touch panel print film was formed on the front and back surfaces (upper and lower surfaces) of the sensor glass was obtained.

[Comparative Example 2]
The touch panel of Comparative Example 2 used the scattering prevention film 13 having a thickness of 120 μm instead of using the touch-panel print film 30 in the one-glass Example 5 shown in FIG. 14. This scattering prevention film 13 was arranged not on the middle of the display device but on the top, that is, on the surface of the sensor glass as the touch panel body 11. The OCA tape as the second optical adhesive layer 22 had a thickness of 175 μm instead of 100 μm. The other points were the same as in Example 5. According to this, the thickness of the touch panel to which the OCA tape of Comparative Example 2 was added was 845 μm, which was thicker than those of Examples 3 to 6 of one glass. That is, even when a frame is formed on the sensor glass surface using a black resist, the touch panel print film is still effective.

[Example 7]
Example 7 is shown in FIG. The touch panel of Example 7 is an on-cell glass type as in Example 1. However, the scattering prevention film provided on the top of the display device is omitted, and this scattering prevention film is used as a sensor glass as the cover glass 21 and the touch panel body 11. The point which was shared by the printing film 30 for touchscreens provided between is different. Further, the touch panel print film is different from the first embodiment in that the touch panel print film of FIG. 8 is used.

The thickness of the touch panel print film 30 was 100 μm. This touch-panel print film 30 has a 30 μm-thick OCA tape as the second optical transparent adhesive layer 22, a 10 μm-thick print layer 35, a 40 μm-thick acrylic resin layer coated and cured as the transparent resin layer 42, The optical transparent adhesive layer 36 was composed of a 30 μm thick OCA tape.

According to Example 7, a touch panel printing film having a thickness of 100 μm, a cover glass for a touch panel having a thickness of 650 μm, and a touch panel having a thickness of 1200 μm were obtained.

[Example 8]
Example 8 is shown in FIG. The touch panel of Example 9 has basically the same configuration as that of Example 7 in FIG. The difference is that the OCA tape as the second optical transparent adhesive layer is not provided on the back surface of the touch-panel print film 30 and is supplied from the film manufacturer. In this case, the OCA tape is attached on the touch panel manufacturer side.

[Comparative Example 3]
The touch panel of Comparative Example 3 used an OCA tape having a thickness of 175 μm instead of using the print film 30 for a touch panel having a thickness of 100 μm in Example 7 shown in FIG. Moreover, the cover glass which formed the frame-like BM layer in the back surface was used for the cover glass instead of the cover glass 21 which is a bare surface on both surfaces. The other points were the same as in Example 7. According to this, the thickness of the obtained OCA tape for touch panel is 175 μm, the thickness of the cover glass for touch panel is 725 μm, and the thickness of the touch panel is 1275 μm. It was thick.

[Appendix]
Hereinafter, preferred embodiments of the present invention will be additionally described.

According to one aspect of the present invention, there is a touch panel print film to be bonded to a touch panel body,
A base film;
A frame-shaped printing layer provided on one surface of the base film;
Optically formed by applying a liquid curable optical transparent resin composition over the surface of the printed layer and one surface of the substrate film in the frame of the printed layer and curing the surface to be flat. A printed film for a touch panel provided with a transparent resin layer is provided.

Preferably, the optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid curable optical transparent adhesive and curing it so that the surface becomes flat. Preferably, the optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid curable optical transparent adhesive and curing it so that the surface becomes flat. A gel-like second transparent adhesive layer for optics is provided on the other surface of the material film.

Preferably, the optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid curable optical transparent adhesive and curing it so that the surface becomes flat. An optical transparent adhesive tape (OCA tape) is provided on the other surface of the material film. Preferably, the base film is polyethylene terephthalate (PET).

Preferably, the optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid-curing optical transparent adhesive and curing the gel so that the surface becomes flat. A hard coat layer is provided on the other surface of the base film. Preferably, the optical transparent resin layer is an acrylic resin layer formed by applying a liquid curable acrylic resin agent and then curing the applied acrylic resin agent, on the acrylic resin layer, An optical transparent adhesive layer formed by applying a gel-like optical transparent adhesive layer or a liquid curable optical transparent adhesive and curing the gel so that the surface becomes flat is provided.

Preferably, the base film is peelable, and the optical transparent resin layer formed on one surface of the base film is cured by applying a liquid curable acrylic resin agent so that the surface becomes flat. Acrylic resin layer formed by
Optically formed by applying a gel-like first optical transparent adhesive layer or a liquid-curing optical transparent adhesive on the acrylic resin layer and curing the gel so that the surface becomes flat. Provide a transparent adhesive layer,
A gel-like second transparent adhesive layer for optics is provided on the exposed surface of the printed layer and the acrylic resin layer exposed by peeling off the base film.

Preferably, the base film is peelable, and the optical transparent resin layer formed on one surface of the base film is cured by applying a liquid curable acrylic resin agent so that the surface becomes flat. Acrylic resin layer formed by
Optical formed by applying a first optical transparent adhesive tape (OCA tape) or a liquid curable optical transparent adhesive on the acrylic resin layer and curing the gel so that the surface becomes flat. For transparent adhesive layer,
A second optical transparent adhesive tape (OCA tape) is provided on the exposed surfaces of the printed layer and the acrylic resin layer exposed by peeling off the base film.

Preferably, the first optical transparent adhesive layer is an optical transparent adhesive tape (OCA tape).

Further, according to another aspect of the present invention, there are provided a touch panel cover glass, a liquid crystal display panel, and a multi-function terminal on which the touch panel print film is bonded.

According to still another aspect of the present invention,
A method for producing a printed film for a touch panel to be bonded to a touch panel body,
Forming a frame-shaped printed layer on one surface of the base film;
A liquid curable optical transparent resin composition is applied over the surface of the printed layer and one surface of the substrate film in the frame of the printed layer to absorb the thickness of the printed layer, and to cure and gel Forming a transparent optical resin layer,
The manufacturing method of the printed film for touchscreens containing is provided.

Preferably, the base film is peelable, and the optical transparent resin layer formed on one surface of the base film absorbs the thickness of the printing layer by applying a liquid curable acrylic resin agent, and is cured. An acrylic resin layer formed by
An optical transparent adhesive tape (OCA tape) is provided on the acrylic resin layer, or a liquid curable optical transparent resin composition is applied to absorb the thickness of the printed layer and cured to form a gel-like optical material. Forming a transparent resin layer.

Preferably, the base film is peelable, and the optical transparent resin layer formed on one surface of the base film absorbs the thickness of the printing layer by applying a liquid curable acrylic resin agent, It is an acrylic resin layer formed by curing,
A first optical transparent adhesive tape (OCA tape) is provided on the acrylic resin layer, or a liquid curable optical transparent resin composition is applied to absorb the thickness of the printed layer and cured to gel. Forming a first optical transparent resin layer having a shape;
Forming a second optical transparent adhesive tape (OCA tape) on the exposed surface of the printed layer and the acrylic resin layer exposed by peeling off the base film.

Moreover, according to another aspect of the present invention, in the method for producing a touch panel print film to be attached to a cover glass that protects a rigid touch panel body,
Forming a frame-shaped printed layer on one surface of the base film to be attached to the cover glass;
Applying a transparent liquid transparent adhesive composition for bonding the cover glass to the entire surface of the base film on which the printing layer is formed;
There is provided a method for producing a printed film for a touch panel, comprising: a step of curing the liquid transparent pressure-sensitive adhesive composition applied to the entire surface of the base film into a gel to form a first optical transparent pressure-sensitive adhesive layer. .

Moreover, according to another aspect of the present invention, in the method for producing a touch panel print film to be attached to a cover glass that protects a rigid touch panel body,
Forming a frame-shaped printed layer on one surface of the base film to be attached to the cover glass;
Applying a transparent liquid transparent adhesive composition for bonding the cover glass to the entire surface of the base film on which the printing layer is formed;
Forming the first optical transparent adhesive layer by curing the liquid transparent adhesive composition coated on the entire surface of the base film into a gel;
And a step of forming a second optical transparent adhesive layer on the entire other surface opposite to the surface on which the printed layer of the base film is not formed.

Moreover, according to another aspect of the present invention, in the method for producing a touch panel print film to be attached to a cover glass that protects a rigid touch panel body,
Forming a frame-shaped printed layer on one surface of the base film to be attached to the cover glass;
Applying a transparent liquid transparent adhesive composition for bonding the cover glass to the entire surface of the base film on which the printing layer is formed;
Forming the first optical transparent adhesive layer by curing the liquid transparent adhesive composition coated on the entire surface of the base film into a gel;
Punching the base film on which the first optical transparent adhesive layer is formed together with the first optical transparent adhesive layer, leaving the base film portion on which the printed layer is formed,
Applying a transparent liquid transparent adhesive composition to the other surface opposite to the remaining one surface of the base film portion so as to be filled in the window formed by punching the base film;
And a step of curing the applied liquid transparent adhesive composition in a gel state to form a second optical transparent adhesive layer, and a method for producing a printed film for a touch panel.

According to still another aspect of the present invention, there is provided a method for producing a touch panel print film to be bonded to a touch panel body,
Forming a printed layer on one surface of the base film;
Providing a gel-like first optically transparent adhesive layer on the other surface of the substrate film;
Cutting the first optically transparent adhesive layer, the base film, and the printed layer in a layer thickness direction to open a window, and forming a frame around the window;
The window is covered with a liner from the first optical transparent adhesive layer side, and a liquid curable optical transparent adhesive is applied over the surface of the printed layer and the liner surface in the frame, The manufacturing method of the printing film for touchscreens including the process which absorbs thickness and hardens the absorbed said transparent adhesive for optics and forms a gel-like 2nd transparent adhesive layer for optics is provided.

10 Touch Panel 11 Touch Panel Body (Sensor Glass)
12 Liquid crystal display panel (LCD panel)
20 Touch Glass Cover Glass 21 Cover Glass 22 Second Optical Transparent Adhesive Layer 25 BM Layer 30 Touch Panel Print Film 31 Base Film (Optical PET Film)
32 One surface 33 Other surface 34 Hard coat layer 35 Print layer 36a Liquid transparent adhesive composition 36 First optical transparent adhesive layer 38 Optical transparent adhesive layer 40 Window 42 Optical transparent resin layer

Claims

A touch panel printing film to be bonded to the touch panel body,
A base film;
A frame-shaped printing layer provided on one surface of the base film;
Optically formed by applying a liquid curable optical transparent resin composition over the surface of the printed layer and one surface of the substrate film in the frame of the printed layer and curing the surface to be flat. A printing film for a touch panel provided with a transparent resin layer.
In the touchscreen printed film of Claim 1,
A printing film for a touch panel, wherein the optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid curable optical transparent adhesive and curing the gel so that the surface becomes flat.
In the touchscreen printed film of Claim 1,
The optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid curable optical transparent adhesive and curing the gel so that the surface becomes flat,
A printed film for a touch panel, wherein a gel-like second transparent adhesive layer for optics is provided on the other surface of the base film.
In the touchscreen printed film of Claim 1,
The optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid curable optical transparent adhesive and curing the gel so that the surface becomes flat,
A printed film for a touch panel, wherein an optical transparent adhesive tape (OCA tape) is provided on the other surface of the base film.
In the touchscreen printed film of Claim 1,
A printed film for a touch panel, wherein the substrate film is polyethylene terephthalate (PET).
In the touchscreen printed film of Claim 1,
The optical transparent resin layer is a first optical transparent adhesive layer formed by applying a liquid curable optical transparent adhesive and curing the gel so that the surface becomes flat,
A printed film for a touch panel, wherein a hard coat layer is provided on the other surface of the base film.
In the touchscreen printed film of Claim 1,
The optical transparent resin layer is an acrylic resin layer formed by applying a liquid curable acrylic resin agent and then curing the applied acrylic resin agent,
A transparent optical adhesive layer formed by applying a gel-like transparent optical adhesive layer or a liquid-curing optical transparent adhesive on the acrylic resin layer and curing the gel so that the surface becomes flat. Printed film for touch panels.
In the touchscreen printed film of Claim 1,
An acrylic resin formed by allowing the base film to be peeled and curing the optical transparent resin layer formed on one surface of the base film by applying a liquid curable acrylic resin agent so that the surface becomes flat. Layer and
Optically formed by applying a gel-like first optical transparent adhesive layer or a liquid-curing optical transparent adhesive on the acrylic resin layer and curing the gel so that the surface becomes flat. Provide a transparent adhesive layer,
The printed film for touch panels which provided the gel-like 2nd transparent adhesive layer for optics on the exposed surface of the said printed layer and the said acrylic resin layer which peeled and removed the said base film.
In the touchscreen printed film of Claim 1,
An acrylic resin formed by allowing the base film to be peeled and curing the optical transparent resin layer formed on one surface of the base film by applying a liquid curable acrylic resin agent so that the surface becomes flat. Layer and
Optical formed by applying a first optical transparent adhesive tape (OCA tape) or a liquid curable optical transparent adhesive on the acrylic resin layer and curing the gel so that the surface becomes flat. For transparent adhesive layer,
A printed film for a touch panel, wherein a second optical transparent adhesive tape (OCA tape) is provided on the exposed surface of the printed layer and the acrylic resin layer exposed by peeling off the base film.
A touch panel printing film to be bonded to the touch panel body,
A base film;
A printing layer provided on one surface of the base film;
A gel-like first optically transparent adhesive layer provided on the other surface of the base film;
A frame formed around a window opened by punching the first optically transparent adhesive layer, the base film, and the printed layer in a layer thickness direction;
A liquid curable optical transparent adhesive is applied over the surface of the frame on the printed layer side and the inside of the window, and the surface of the frame and the surface of the window, and the first optical transparent adhesive. A printed film for a touch panel, comprising: a second optically transparent adhesive layer formed by curing the back surface of the frame on the layer side and the back surface of the window in a gel state so as to be flat.
The printed film for a touch panel according to claim 10,
A printed film for a touch panel, wherein the first optical transparent adhesive layer is an optical transparent adhesive tape (OCA tape).
A touch panel cover glass on which the touch panel print film according to claim 1 is bonded.
A liquid crystal display panel on which the touch-panel printing film according to claim 1 is bonded.
A multi-function terminal to which the touch-panel printing film according to claim 1 is bonded.
A method for producing a printed film for a touch panel to be bonded to a touch panel body,
Forming a frame-shaped printed layer on one surface of the base film;
A liquid curable optical transparent resin composition is applied across the surface of the printed layer and one surface of the substrate film in the frame of the printed layer to absorb the thickness of the printed layer and cure it for optical use. Forming a transparent resin layer;
Of a printed film for a touch panel comprising:
In the manufacturing method of the printed film for touchscreens of Claim 15,
The base film is peelable, and the optical transparent resin layer formed on one surface of the base film is formed by applying a liquid curable acrylic resin agent to absorb the thickness of the printing layer and curing it. Acrylic resin layer,
An optical transparent adhesive tape (OCA tape) is provided on the acrylic resin layer, or a liquid curable optical transparent resin composition is applied to absorb the thickness of the printed layer and cured to form a gel-like optical material. A method for producing a printed film for a touch panel, further comprising the step of forming a transparent resin layer.
It is a manufacturing method of the printed film for touchscreens of Claim 15,
The base film is peelable, and the optical transparent resin layer formed on one surface of the base film is formed by applying a liquid curable acrylic resin agent to absorb the thickness of the printing layer and curing it. Acrylic resin layer,
A first optical transparent adhesive tape (OCA tape) is provided on the acrylic resin layer, or a liquid curable optical transparent resin composition is applied to absorb the thickness of the printed layer and cured to gel. Forming a first optical transparent resin layer having a shape;
The printing layer for touch panel further comprising the step of forming a second optical transparent adhesive tape (OCA tape) on the exposed surface of the printed layer and the acrylic resin layer exposed by peeling off the base film. Method.