JP2020121539A - Transparent conductive film laminate - Google Patents

Abstract

To provide a transparent conductive film laminate which suppresses the generation of curling and outgas.SOLUTION: There is provided a transparent conductive film laminate 100 which comprises a conductive film 10 including a resin film 14 and a conductive membrane 11 and a carrier film 20 which includes a base film 22 containing a thermoplastic plastic and an adhesive layer 21 arranged on one side of the base film and is temporarily adhered to the conductive film so as to be peelable via the adhesive layer, wherein the carrier film is laminated on a side opposite to the conductive membrane of the conductive film, the base film has a glass transition temperature (Tg) of 150°C or more, the dimensional shrinkage at 145°C is 0.2% or less in the first direction and in the second direction orthogonal to the first direction, respectively, and the MIT number is 500 times or more.SELECTED DRAWING: Figure 1

Description

The present invention relates to a transparent conductive film laminate.

A transparent conductive film used for a touch panel or the like is practically used by temporarily attaching a carrier film to form a laminated body, and the laminated body is manufactured, transported, or stored. However, in the conventional transparent conductive film laminate, curling may occur during the heating step, resulting in insufficient production efficiency.

JP, 2017-190406, A

The present invention has been made to solve the above conventional problems, and an object of the present invention is to provide a transparent conductive film laminate in which the generation of curl and outgas is suppressed.

The transparent conductive film laminate according to the embodiment of the present invention includes a conductive film including a resin film and a conductive film; a base film including a thermoplastic, and an adhesive layer disposed on one side of the base film. A carrier film releasably temporarily attached to the conductive film via the pressure-sensitive adhesive layer; and the carrier film is laminated on the side of the conductive film opposite to the conductive film. The glass transition temperature (Tg) of the base film is 150° C. or higher, and the dimensional shrinkage ratio at 145° C. is 0.2% in the first direction and the second direction orthogonal to the first direction. Below, the number of MITs is 500 or more.
In one embodiment, the thermoplastic comprises 1 wt% to 15 wt% glutarimide units, 1 wt% to 6 wt% methacrylic acid units, and 0.5 wt% to 10 wt% methacrylic anhydride units. % And a copolymer containing methyl methacrylate units as the remaining content.
In one embodiment, the thermoplastic is a polymer mixture containing 10% by weight to 90% by weight of component (A) and 90% by weight to 10% by weight of component (B). Is a copolymer containing 80% by weight to 99% by weight of methyl methacrylate units and 1% by weight to 15% by weight of glutarimide units, and the component (B) contains polymethylmethacrylate.
In one embodiment, the carrier film has a thickness of 15 μm to 100 μm.

According to an embodiment of the present invention, in a transparent conductive film laminate having a transparent conductive film and a carrier film, a predetermined thermoplastic is included, and a second direction orthogonal to the first direction and the first direction is included. By using a base film that has a small dimensional shrinkage in any of the above directions and the number of MITs is 500 times or more, it is possible to obtain a transparent conductive film laminate in which curling and outgas generation are suppressed.

It is a schematic sectional drawing of the transparent conductive film laminated body by one Embodiment of this invention.

Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not limited to these embodiments.

A. Transparent Conductive Film Laminate FIG. 1 is a schematic sectional view of a transparent conductive film laminate according to one embodiment of the present invention. The transparent conductive film laminate 100 of the illustrated example has a transparent conductive film 10 and a carrier film 20. The transparent conductive film 10 typically has a resin film 14 and a conductive layer 11. The carrier film 20 typically has a base film 22 and a pressure-sensitive adhesive layer 21, and is temporarily releasably attached to the transparent conductive film 10 via the pressure-sensitive adhesive layer 21. The carrier film may have an anti-blocking hard coat (ABHC) layer 23 if necessary.

In the embodiment of the present invention, the glass transition temperature (Tg) of the base film 22 is 150° C. or higher, preferably 155° C. or higher. Furthermore, the dimensional shrinkage ratio of the base film 22 at 145° C. is 0.2% or less in the first direction and the second direction orthogonal to the first direction. The first direction corresponds to, for example, the MD direction in the manufacturing method described later, and the second direction corresponds to, for example, the TD direction. Furthermore, the number of MITs of the base film 22 is 500 times or more. When the glass transition temperature (Tg) of the base film 22 and the dimensional shrinkage ratio at 145° and the number of MITs are in such ranges, a transparent conductive film laminate in which curling and outgas generation are suppressed can be obtained. obtain. Furthermore, the folding endurance of the base film 22 is preferably 100 times or more.

The thickness of the carrier film 20 is preferably 15 μm to 100 μm, more preferably 15 μm to 80 μm, and further preferably 15 μm to 60 μm. When the thickness of the carrier film is in such a range, curling and outgassing are suppressed, and a transparent conductive film laminate having excellent folding resistance can be obtained. The thickness of the carrier film is the total thickness of the base film, the pressure-sensitive adhesive layer, and the antiblocking hard coat (ABHC) layer, if necessary.

B. Transparent Conductive Film The transparent conductive film 10 according to the embodiment of the present invention includes a resin film 14 and a conductive layer 11. The conductive layer is typically formed on the visible side surface of the resin film. The transparent conductive film may have an index matching (IM) layer 12, a hard coat (HC) layer 13 and/or an anti-blocking hard coat (ABHC) layer 15 as necessary.

(Resin film)
The resin film may be composed of any appropriate resin. Examples of the resin forming the resin film include cycloolefin resin (COP) and acrylic resin. Details of the cycloolefin resin (COP) are described in, for example, JP-A-2016-107503. The description of the publication is incorporated herein by reference.

The thickness of the resin film is preferably 10 μm to 80 μm, more preferably 10 μm to 60 μm, and further preferably 10 μm to 40 μm.

(Conductive layer)
The conductive layer is typically a transparent conductive layer. The total light transmittance of the conductive layer is preferably 80% or more, more preferably 85% or more, still more preferably 90% or more.

The density of the conductive layer is preferably ^{1.0g / cm 3 ~10.5g / cm 3} , more preferably from ^{1.3g / cm 3 ~8.0g / cm 3} .

The surface resistance value of the conductive layer is preferably 0.1Ω/□ to 1000Ω/□, more preferably 0.5Ω/□ to 500Ω/□, and further preferably 1Ω/□ to 250Ω/□.

A typical example of the conductive layer is a conductive layer containing a metal oxide. Examples of the metal oxide include indium oxide, tin oxide, zinc oxide, indium-tin complex oxide, tin-antimony complex oxide, zinc-aluminum complex oxide, and indium-zinc complex oxide. Of these, indium-tin composite oxide (ITO) is preferable.

The thickness of the conductive layer is preferably 0.01 μm to 0.06 μm, more preferably 0.01 μm to 0.045 μm. Within such a range, a conductive layer having excellent conductivity and light transmittance can be obtained.

The conductive layer can be typically formed on the surface of the resin film by sputtering.

(Index matching (IM) layer)
The IM layer may be formed on the surface on one side of the conductive layer. A configuration well known in the industry can be adopted for the IM layer, and thus detailed description thereof will be omitted.

(Hard coat (HC) layer)
The HC layer may be formed between the IM layer and the resin film. A well-known configuration in the industry can be adopted for the HC layer, so a detailed description thereof will be omitted.

(Anti-blocking hard coat (ABHC) layer)
The ABHC layer may be formed on the surface of the resin film opposite to the HC layer. Details of the ABHC layer are described in, for example, JP-A-2016-107503. The description of the publication is incorporated herein by reference.

C. Carrier Film The carrier film 20 includes an adhesive layer 21 and a base film 22. The carrier film 20 may have an anti-blocking hard coat (ABHC) layer 23, if necessary.

(Base film)
The base film according to the embodiment of the present invention is composed of a film that includes a thermoplastic and preferably further includes an elastomer.

(Thermoplastic)
Thermoplastics typically include 1 wt% to 15 wt% glutarimide units, 1 wt% to 6 wt% methacrylic acid units, 0.5 wt% to 10 wt% methacrylic anhydride units, and the balance. Contains a copolymer consisting mainly of methylmethacrylate units. The copolymer typically contains 69% by weight to 97.5% by weight of methyl methacrylate units. The copolymer may contain monomer units other than the above.

Thermoplastics are characterized by a haze below 2% (haze value, 23° C.).

The thermoplastic is typically a polymer mixture containing 10% to 90% by weight of component (A) and 90% to 10% by weight of component (B). The component (A) is a copolymer containing 80 wt% to 99 wt% of methyl methacrylate units and 1 wt% to 15 wt% of glutarimide units, and the component (B) contains polymethyl methacrylate.

As component B, impact-resistant modified polymethylmethacrylate may be included.

Thermoplastics are characterized by a haze below 2% (haze value, 23° C.).

Examples of thermoplastics include polymethylmethacrylate (PMMA) and polymethylmethacrylimide (PMMI).

Details of thermoplastics are described in, for example, JP-A-2006-57104. The description of the publication is incorporated herein by reference.

A commercially available product may be used as the thermoplastic. Examples of commercially available products include polymethylmethacrylimide (PMMI), product name “PLEXIMID TT50” manufactured by Daicel-Evonik.

(Elastomer)
Any appropriate elastomer can be used as the elastomer. Representative examples of elastomers include acrylic elastomers, rubbery polymers, polyamide elastomers, polyethylene elastomers, styrene elastomers and butadiene elastomers. The elastomers may be used alone or in combination.

A commercially available product may be used as the acrylic elastomer. Examples of the commercially available product include "High heat resistant grade XB series" manufactured by Aron Kasei Co., Ltd.

Examples of the styrene-based elastomer include elastomers containing polystyrene, which is a hard segment, and polybutadiene, polyisoprene, and a copolymer of polybutadiene and polyisoprene, which are soft segments, and hydrogenated products thereof.

The blending ratio of the above thermoplastics and the above elastomers is preferably 70:30 to 99:1, more preferably 85:15 to 95:5.

The thickness of the base film is preferably 10 μm to 80 μm, more preferably 10 μm to 60 μm, and further preferably 10 μm to 40 μm.

The elastic modulus of the base film is preferably 50 MPa to 350 MPa at a tensile speed of 100 mm/min. When the elastic modulus is within such a range, a base film having excellent transportability and operability can be obtained. According to the embodiment of the present invention, it is possible to achieve both excellent elastic modulus (strength) and excellent flexibility or bending resistance (softness) as described above. The elastic modulus is measured according to JIS K 7127:1999.

The tensile elongation of the base film is preferably 70% to 200%. When the tensile elongation is in such a range, it has an advantage that it is unlikely to break during transportation. The tensile elongation is measured according to JIS K 6781.

(Method of manufacturing base film)
A method for producing a base film according to an embodiment of the present invention is to form a film-forming material (resin composition) containing the thermoplastic resin according to the above item C and, if necessary, an elastomer into a film, and the molding. Stretching the formed film.

The film-forming material may contain the above-mentioned other resin in addition to the thermoplastic resin, may contain an additive, and may contain a solvent. Any appropriate additive can be adopted as the additive depending on the purpose. Specific examples of the additives include reactive diluents, plasticizers, surfactants, fillers, antioxidants, antioxidants, ultraviolet absorbers, leveling agents, thixotropic agents, antistatic agents, conductive materials, flame retardants. Is mentioned. The number, type, combination, addition amount, etc. of the additives can be appropriately set according to the purpose.

As a method for forming a film from the film-forming material, any suitable molding method can be adopted. Specific examples include compression molding method, transfer molding method, injection molding method, extrusion molding method, blow molding method, powder molding method, FRP molding method, cast coating method (for example, casting method), calender molding method, heat press. Law etc. are mentioned. An extrusion molding method or a cast coating method is preferable. This is because the smoothness of the obtained film can be improved and good optical uniformity can be obtained. The molding conditions can be appropriately set depending on the composition and type of the resin used, the characteristics desired for the base film, and the like.

The stretching method of the film is typically biaxial stretching, and more specifically, sequential biaxial stretching or simultaneous biaxial stretching. This is because a base film having a small in-plane retardation can be obtained. Sequential biaxial stretching or simultaneous biaxial stretching is typically performed using a tenter stretching machine. Therefore, the stretching direction of the film is typically the length direction and the width direction of the film.

The stretching temperature may vary depending on the in-plane retardation and thickness desired for the base film, the type of resin used, the thickness of the film used, the stretching ratio, and the like. Specifically, the stretching temperature is preferably Tg+5° C. to Tg+50° C., and more preferably Tg+10° C. to Tg+40° C. with respect to the glass transition temperature (Tg) of the film. By stretching at such a temperature, a base film having suitable properties in the embodiment of the present invention can be obtained.

The draw ratio may vary depending on the in-plane retardation and thickness desired for the base film, the type of resin used, the thickness of the film used, the drawing temperature, and the like. When biaxial stretching (for example, sequential biaxial stretching or simultaneous biaxial stretching) is adopted, the stretching ratio in the first direction (for example, the length direction) and the stretching in the second direction (for example, the width direction). The magnification is preferably as small as possible, more preferably substantially equal. With such a configuration, a resin film having a small in-plane retardation can be obtained. When biaxial stretching (for example, sequential biaxial stretching or simultaneous biaxial stretching) is adopted, the stretching ratio is in the first direction (for example, the length direction) and the second direction (for example, the width direction). For each, it can be, for example, 1.1 times to 3.0 times.

In the embodiment of the present invention, the stretching rate is preferably 10%/sec or less, more preferably 7%/sec or less, further preferably 5%/sec or less, and particularly preferably 2.5. %/Second or less. A base film having a small in-plane retardation can be obtained by stretching a film containing a specific thermoplastic as described above at such a low stretching speed. The lower limit of the stretching speed can be, for example, 1.2%/sec. If the stretching speed is too low, the productivity may not be practical. When biaxial stretching (for example, sequential biaxial stretching or simultaneous biaxial stretching) is adopted, the stretching speed in the first direction (for example, the length direction) and the second direction (for example, the width direction) The stretching speed is preferably as small as possible, more preferably substantially equal. With such a configuration, the in-plane retardation Re(550) of the base film can be made small.

(Adhesive layer)
The pressure-sensitive adhesive layer may be used without particular limitation as long as it has transparency. Specifically, for example, acrylic-based polymers, silicone-based polymers, polyesters, polyurethanes, polyamides, polyvinyl ethers, vinyl acetate/vinyl chloride copolymers, modified polyolefins, epoxy-based, fluorine-based, natural rubber, rubber such as synthetic rubber, etc. A polymer having the above polymer as a base polymer can be appropriately selected and used. In particular, an acrylic pressure-sensitive adhesive is preferably used because it is excellent in optical transparency, exhibits appropriate wettability, cohesiveness, adhesiveness, and other adhesive properties and is also excellent in weather resistance, heat resistance, and the like.

For the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer, a tackifier, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a silane coupling agent and the like can be appropriately used, if necessary. The thickness of the pressure-sensitive adhesive layer is preferably 5 μm to 100 μm, more preferably 10 μm to 50 μm, and further preferably 15 μm to 35 μm.

(Anti-blocking hard coat (ABHC) layer)
Since the structure is the same as that of the ABHC layer in the transparent conductive film, detailed description will be omitted.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples. The method of measuring each characteristic in the examples is as follows. In the examples, “parts” and “%” are based on weight unless otherwise specified.

(1) MIT test The MIT test was performed according to JIS P8115. Specifically, the base films obtained in the examples and comparative examples were cut into a length of 15 cm and a width of 1.5 cm to obtain measurement samples. The measurement sample was attached to a MIT folding fatigue tester BE-202 type (manufactured by Tester Sangyo Co., Ltd.) (load 1.0 kgf, clamp R: 0.38 mm), and a test speed of 90 cpm and a bending angle of 90° were repeated 500 times. Repeated bending was performed as the upper limit, and the number of times of bending when the measurement sample was broken was used as the test value.
(2) Folding resistance test The 180° bending test was repeated 100 times for the base films obtained in the examples and comparative examples, and the number of times of bending when the measurement sample was broken was taken as the test value.
(3) Dimensional Shrinkage Ratio The thermal shrinkage ratios in the longitudinal direction (MD direction) and the width direction (TD direction) of the base films obtained in Examples and Comparative Examples were measured as follows. Specifically, the base film was cut into a width of 100 mm and a length of 100 mm (test piece), and four corners were scratched with a cloth, and the length of the four points in the center of the cross scratch before heating in the MD and TD directions ( mm) was measured by a CNC coordinate measuring machine (LEGEX774 manufactured by Mitutoyo Corporation). Then, it put into the oven and heat-processed (145 degreeC, 60 minutes). After cooling for 1 hour at room temperature, the lengths (mm) after heating in the MD and TD directions at the four points of the four corners are measured again by a CNC coordinate measuring machine, and the measured values are substituted into the following formula. The heat shrinkage rates in the MD direction and the TD direction were obtained.
Thermal shrinkage (%)=[[length before heating (mm)-length after heating (mm)]/length before heating (mm)]×100
(4) Outgas The base films obtained in Examples and Comparative Examples were cut into a width of 100 mm and a length of 100 mm (test piece), a surface to be bonded to the transparent conductive film and the other surface were coated with an adhesive, A test piece was obtained by sticking the adhesive surface on one side of an alkali glass. The obtained test piece was placed in an autoclave under the conditions of 50° C. and 0.5 atm, and after 15 minutes, the sample was taken out. did.
(5) Curl The transparent conductive layer film laminates obtained in Examples and Comparative Examples were cut into a size of 20 cm×20 cm. After heating at 145° C. for 60 minutes with the ITO surface facing upward, the mixture was allowed to cool at room temperature (23° C.) for 1 hour. Then, the sample was placed on a horizontal surface with the ITO layer facing upward, and the height from the horizontal plane of the central portion (curl value A) was measured. Further, the heights of the four corners from the horizontal plane were measured, and the average value (curl value B) was calculated. A value obtained by subtracting the curl value B from the curl value A (AB) was calculated as the curl amount. If the curl value was in the range of 0 mm to 50 mm, it was evaluated as ◯, and the others were evaluated as x.

<Example 1>
1-1. Preparation of transparent conductive film Anti-blocking was performed on the surface on one side of the product name "ZEONOR (registered trademark)" (thickness: 50 µm, Tg: 165°C) manufactured by Nippon Zeon Co., Ltd., which is a polycycloolefin (COP) film. A hard coat (ABHC) layer was formed, and a hard coat (HC) layer was formed on the surface opposite to the ABHC layer. An index matching (IM) layer was formed on the surface of the HC layer opposite to the resin film. On the surface of the IM layer opposite to the HC layer, ITO was sputtered to form a conductive layer to obtain a transparent conductive film (thickness 25 μm).

1-2. Preparation of thermoplastic/elastomer mixed resin film Polymethylmethacrylimide (PMMI) resin, product name “PLEXIMID TT50” (Tg: 151° C.) manufactured by Daicel-Evonik Co., Ltd., 90 parts, and acrylic elastomer, Aron After mixing 10 parts of the product name "High heat resistance grade XB series" manufactured by Kasei Co., Ltd. and vacuum-drying at 100°C for 5 hours, a single-screw extruder (Isuzu Kakoki Co., Ltd., screw diameter 25 mm, cylinder set temperature: 275) C.), T-die (width 200 mm, setting temperature: 275° C.), chill roll (setting temperature: 120 to 130° C.) and a film forming apparatus equipped with a winder, and a PMMI/elastomer mixed resin film having a thickness of 100 μm. Was produced.

1-3. Preparation of Base Film The PMMI/elastomer mixed resin film obtained above was simultaneously biaxially stretched twice in the length direction and the width direction to obtain a base film. The number of MITs of the obtained base film was 500 times or more, the number of folding endurances was 100 times or more, and the dimensional change rate (MD/TD) was 0.16/0.18.

1-4. Preparation of Carrier Film By a normal solution polymerization, an acrylic polymer having a weight average molecular weight of 600,000 was obtained with butyl acrylate/acrylic acid=100/6 (weight ratio). To 100 parts by weight of this acrylic polymer, 6 parts by weight of an epoxy crosslinking agent (trade name “Tetrad C (registered trademark)” manufactured by Mitsubishi Gas Chemical Co., Ltd.) was added to prepare an acrylic adhesive. The acrylic pressure-sensitive adhesive obtained as described above was applied onto the release-treated surface of the release-treated PET film, and heated at 120° C. for 60 seconds to form a pressure-sensitive adhesive layer having a thickness of 20 μm. Then, a PET film was attached to one surface of the base film via an adhesive layer. Then, the release-treated PET film was peeled off, an antiblocking hard coat (ABHC) layer was formed on the surface opposite to the pressure-sensitive adhesive layer, and a carrier film (thickness 40 μm) was produced.

1-5. Preparation of transparent conductive film laminate A carrier film was detachably temporarily attached via a pressure-sensitive adhesive layer to the surface of the transparent conductive film on which the conductive film was not formed to form a transparent conductive film laminate. .. The obtained transparent conductive film laminate was subjected to the evaluations of (4) and (5) above. The results are shown in Table 1.

<Example 2>
A transparent conductive film was obtained in the same manner as in Example 1 except that the thickness of the transparent conductive film was 15 μm. Further, a carrier film was obtained in the same manner as in Example 1 except that the thickness of the carrier film was 25 μm, the amount of PMMI resin added was 80 parts, and the amount of elastomer added was 20 parts. The MIT number of times of the base film used for producing the carrier film was 500 times or more, the folding endurance number of times was 100 times or more, and the dimensional change rate (MD/TD) was 0.14/0.12. Using the above transparent conductive film and carrier film, a transparent conductive film laminate was obtained in the same manner as in Example 1. The obtained transparent conductive film laminate was subjected to the evaluations of (4) and (5) above. The results are shown in Table 1.

<Example 3>
A transparent conductive film was obtained in the same manner as in Example 1 except that the thickness of the transparent conductive film was 40 μm. Further, a carrier film was obtained in the same manner as in Example 1 except that the thickness of the carrier film was 100 μm. The MIT number of times of the base film used for producing the carrier film was 500 times or more, the folding endurance number of times was 100 times or more, and the dimensional change rate (MD/TD) was 0.19/0.18. Using the above transparent conductive film and carrier film, a transparent conductive film laminate was obtained in the same manner as in Example 1. The obtained transparent conductive film laminate was subjected to the evaluations of (4) and (5) above. The results are shown in Table 1.

<Example 4>
A transparent conductive film was obtained in the same manner as in Example 1 except that the product name "PLEXIMID TT50" manufactured by Daicel-Evonik Co., Ltd., which was a polymethylmethacrylimide (PMMI) resin, was used. Further, a carrier film was obtained in the same manner as in Example 1 except that 95 parts of PMMI and 5 parts of elastomer were added. The MIT number of times of the base film used for producing the carrier film was 500 times or more, the folding endurance number of times was 100 times or more, and the dimensional change rate (MD/TD) was 0.16/0.12. Using the above transparent conductive film and carrier film, a transparent conductive film laminate was obtained in the same manner as in Example 1. The obtained transparent conductive film laminate was subjected to the evaluations of (4) and (5) above. The results are shown in Table 1.

<Comparative Example 1>
A transparent conductive film was obtained in the same manner as in Example 1. Further, a carrier film was obtained in the same manner as in Example 1 except that a polycarbonate (PC) resin (Tg: 147° C.) was used and 100 parts of the PC resin was added and no elastomer was added. The MIT number of times of the base film used for producing the carrier film was 500 times or more, the folding endurance number of times was 100 times or more, and the dimensional change rate (MD/TD) was 0.13/0.1. Using the above transparent conductive film and carrier film, a transparent conductive film laminate was obtained in the same manner as in Example 1. The obtained transparent conductive film laminate was subjected to the evaluations of (4) and (5) above. The results are shown in Table 1.

<Comparative example 2>
A transparent conductive film was obtained in the same manner as in Example 1 except that the thickness was 40 μm. Further, a carrier film was obtained in the same manner as in Example 1 except that a polyester resin (Tg: 155° C.) was used and the thickness was 110 μm. The MIT number of times of the base film used for producing the carrier film was 500 times or more, the folding endurance number of times was 100 times or more, and the dimensional change rate (MD/TD) was 0.22/0.22. Using the above transparent conductive film and carrier film, a transparent conductive film laminate was obtained in the same manner as in Example 1. The obtained transparent conductive film laminate was subjected to the evaluations of (4) and (5) above. The results are shown in Table 1.

<Comparative example 3>
A transparent conductive film was obtained in the same manner as in Example 1. Furthermore, the product name “ZEONOR (registered trademark)” (Tg: 160° C.) manufactured by Nippon Zeon Co., Ltd., which is a polycycloolefin (COP) film, was used, and 100 parts of COP was added and no elastomer was added. A carrier film was obtained in the same manner as in Example 1 except for the above. The number of MITs of the base film used for producing the carrier film was 150, the number of folding endurance was 63, and the dimensional change rate (MD/TD) was 0.05/0.06. Using the above transparent conductive film and carrier film, a transparent conductive film laminate was obtained in the same manner as in Example 1. The obtained transparent conductive film laminate was subjected to the evaluations of (4) and (5) above. The results are shown in Table 1.

<Evaluation>
As is clear from Table 1, the transparent conductive film laminates of the examples of the present invention have suppressed outgassing and curling. This can be realized when the carrier film contains a specific thermoplastic, the dimensional change rate of the thermoplastic when heated at 145° C. for 1 hour is not more than a predetermined value, and the number of MITs is not less than 500. It is presumed that.

The transparent conductive film laminate of the present invention is suitably used for a touch panel.

10 Transparent Conductive Film 11 Conductive Layer 12 Index Matching (IM) Layer 13 Hard Coat (HC) Layer 14 Resin Film 15 Antiblocking Hardcoat (ABHC) Layer 20 Carrier Film 21 Adhesive Layer 22 Base Film 23 Antiblocking Hardcoat ( ABHC) layer 100 transparent conductive film laminate

Claims (4)

A conductive film including a resin film and a conductive film; a base film including a thermoplastic, and a pressure-sensitive adhesive layer disposed on one side of the base film, and the conductive film via the pressure-sensitive adhesive layer. A carrier film detachably temporarily attached to
The carrier film is laminated on the side of the conductive film opposite to the conductive film,
The glass transition temperature (Tg) of the base film is 150° C. or higher, and the dimensional shrinkage ratio at 145° C. is 0.2% or less in the first direction and the second direction orthogonal to the first direction. Yes, the number of MITs is 500 or more,
Transparent conductive film laminate. The thermoplastic contains 1 wt% to 15 wt% of glutarimide units, 1 wt% to 6 wt% of methacrylic acid units, 0.5 wt% to 10 wt% of methacrylic anhydride units, and the remaining contents. The transparent conductive film laminate according to claim 1, which contains a copolymer containing a methyl methacrylate unit. The thermoplastic is
A polymer mixture containing 10% by weight to 90% by weight of the component (A) and 90% by weight to 10% by weight of the component (B),
The component (A) is a copolymer containing 80% by weight to 99% by weight of methyl methacrylate units and 1% by weight to 15% by weight of glutarimide units,
The component (B) contains polymethylmethacrylate,
The transparent conductive laminate according to claim 1. The transparent conductive film laminate according to claim 1, wherein the carrier film has a thickness of 15 μm to 100 μm.

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