WO2018180926A1

WO2018180926A1 - Film with conductive layer, touch panel, method for producing film with conductive layer, and method for producing touch panel

Info

Publication number: WO2018180926A1
Application number: PCT/JP2018/011518
Authority: WO
Inventors: 耕司上岡; 昭典佐伯; 西山　雅仁
Original assignee: 東レ株式会社
Priority date: 2017-03-29
Filing date: 2018-03-22
Publication date: 2018-10-04
Also published as: JP7140108B2; CN110447005A; KR102524863B1; JPWO2018180926A1; TW201838820A; TWI772393B; KR20190134602A; CN110447005B

Abstract

Provided is a film with a conductive layer, which has a conductive layer that contains conductive particles on a resin film that contains a polyimide having an imide group concentration as determined by formula (I) of from 20.0% to 36.5% (inclusive), and which has a gas barrier layer between the resin film and the conductive layer. This film with a conductive layer is applicable, for example, to a touch panel. A method for producing this film with a conductive layer is applicable, for example, to a method for producing a touch panel. (Molecular weight of imide group moiety)/(molecular weight of repeating unit of polyimide) × 100 [%] (I)

Description

Film with conductive layer, touch panel, method for producing film with conductive layer, and method for producing touch panel

The present invention relates to a film with a conductive layer, a touch panel, a method for manufacturing a film with a conductive layer, and a method for manufacturing a touch panel.

In recent years, flexible devices are desired from the viewpoints of design, convenience, and durability in devices such as mobile phones and tablets. However, there are various problems in making equipment flexible, and it has not yet been put into practical use.

Among them, the main problems are improvement in bending resistance, visibility and conductivity of a film with a conductive layer used in equipment. Conventionally, as a film with a conductive layer, a thin film made of a transparent conductive metal such as ITO has been widely used from the viewpoint of improving visibility. For example,

Patent Documents

1 and 2 disclose a transparent conductive film in which a thin film made of ITO is formed on a polyimide film having excellent heat resistance. By patterning the thin film by etching, a film with a conductive layer excellent in visibility and conductivity can be obtained. However, since the ITO wiring is rigid and brittle, there is a problem that bending resistance is low and cracking occurs when bent.

Therefore, various wiring technologies such as metal mesh wiring, metal nanowire wiring, and carbon nanotube wiring have been proposed as transparent conductive layers replacing ITO. Among these, metal mesh wiring is attracting attention as a transparent conductive layer having both bending resistance, visibility, and high conductivity.

Metal mesh wiring can be obtained by forming a metal wiring that is thin enough to be invisible to the mesh pattern. For example, by using a metal having a small electrical resistance value, such as gold, silver, or copper, a wiring with good conductivity can be obtained. Furthermore, the bending resistance of the wiring can be improved by containing an appropriate amount of an organic component that can be patterned by photolithography and has excellent flexibility. Such metal mesh wiring can sufficiently cope with flexibility.

As a method for forming such a metal mesh wiring, for example, a conductive paste composed of conductive metal particles (hereinafter referred to as conductive particles as appropriate) and an organic component is used, and patterning is performed by screen printing, inkjet, photolithography, or the like. The method of doing is mentioned. However, in order to form a fine pattern that cannot be visually recognized, it is necessary to reduce the particle size of the conductive particles to nano size. Such conductive particles have a problem of being easily fused and aggregated even at room temperature. In addition, there is a problem that the surface of the conductive particles reacts with an organic component and the storage stability of the conductive paste is lowered. Further, when pattern processing is performed using photolithography, the conductive particles have light reflectivity, which scatters exposure light, and thus there is a problem that it is difficult to form a fine pattern.

On the other hand, a method for solving the above problem by using conductive particles having a coating layer is disclosed (for example, see Patent Document 3). The surface activity of the conductive particles can be reduced by the coating layer, and at least one of the reaction between the conductive particles and the reaction between the conductive particles and the organic component can be suppressed. Even when photolithography is used, scattering of exposure light can be suppressed and wiring can be patterned with high accuracy. The coated conductive particles can be easily removed by heating at a high temperature of about 200 ° C. Therefore, sufficient electrical conductivity can be expressed in the wiring.

JP 2016-186936 A Japanese Patent No. 5773090 JP 2013-196997 A

However, the technique disclosed in Patent Document 3 requires heating at about 200 ° C. in the presence of oxygen in order to remove the coating layer of conductive particles. For this reason, high heat resistance and oxidation resistance are required for the substrate, and substantially only a glass substrate can be applied. As a matter of course, it is difficult to cope with flexibility using a glass substrate. Furthermore, even when a film with excellent heat resistance is used, the color may deteriorate due to the coloration of the film by heating in the presence of oxygen, and the dimensional accuracy of the film may decrease and misalignment may occur. There has been a problem that an appearance defect called moire occurs.

This invention is made | formed in view of the said situation, The place made into the objective is suppressing the yellowing at the time of conductive layer formation, and the film with a conductive layer which was excellent in the dimensional accuracy of the conductive layer, a touch panel, conductive It is providing the manufacturing method of a film with a layer, and the manufacturing method of a touch panel.

As a result of intensive studies, the inventors of the present invention have a structure in which a gas barrier layer is provided between a conductive film and a resin film (polyimide resin film) containing polyimide having a specific imide group concentration. It has been found that the polyimide resin film can be prevented from coming into contact with oxygen during heating of the layer, and the deterioration of the color and dimensional accuracy of the polyimide resin film can be suppressed.

That is, in order to solve the above-described problems and achieve the object, the film with a conductive layer according to the present invention has an imide group concentration defined by the following formula (I) of 20.0% or more and 36.5% or less. A film with a conductive layer having a conductive layer containing conductive particles on a resin film containing a certain polyimide, wherein a gas barrier layer is provided between the resin film and the conductive layer.

(Molecular weight of the imide group) / (Molecular weight of the repeating unit of polyimide) x 100 [%]
... (I)

The film with a conductive layer according to the present invention is characterized in that, in the above invention, the glass transition temperature of the resin film is 250 ° C. or higher.

Moreover, the film with a conductive layer according to the present invention is characterized in that, in the above invention, the polyimide includes a structural unit represented by the following general formula (1).

(In General Formula (1), R ¹ has a monocyclic or condensed polycyclic alicyclic structure, a tetravalent organic group having 4 to 40 carbon atoms, or a monocyclic alicyclic structure. A tetravalent organic group having 4 to 40 carbon atoms in which the organic groups are connected to each other directly or via a crosslinked structure, R ² represents a divalent organic group having 4 to 40 carbon atoms.

Moreover, the film with a conductive layer according to the present invention is characterized in that, in the above invention, the polyimide includes a structural unit represented by the following general formula (2).

(In General Formula (2), R ³ represents a tetravalent organic group having 4 to 40 carbon atoms. R ⁴ has a monocyclic or condensed polycyclic alicyclic structure and has 4 to 40 carbon atoms. Or a divalent organic group having 4 to 40 carbon atoms in which organic groups having a monocyclic alicyclic structure are connected to each other directly or via a crosslinked structure, or the following general group A divalent organic group represented by the formula (3) is shown.)

(In General Formula (3), X ¹ is a divalent hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a halogen atom. Ar ¹ and Ar ² are each independently a carbon number. Represents a divalent aromatic group of 4 to 40.)

Moreover, the film with a conductive layer according to the present invention is the above invention, wherein the polyimide has a structural unit represented by the following general formula (4) as a main component and is represented by the following general formula (5). The structural unit is characterized by containing 5 mol% or more and 30 mol% or less of all structural units.

(In the general formulas (4) and (5), R ¹ represents a monovalent or condensed polycyclic alicyclic structure, a tetravalent organic group having 4 to 40 carbon atoms, or a monocyclic fatty acid. A tetravalent organic group having 4 to 40 carbon atoms in which organic groups having a ring structure are connected to each other directly or via a crosslinked structure, R ¹³ is a divalent group represented by the following general formula (6). R ¹⁴ is a structure represented by the following structural formula (7) or the following structural formula (8).

(In the general formula (6), R ¹⁵ to R ²² each independently represent a hydrogen atom, a halogen atom, or a monovalent organic group having 1 to 3 carbon atoms which may be substituted with a halogen atom. X ² is selected from a direct bond, an oxygen atom, a sulfur atom, a sulfonyl group, a divalent organic group having 1 to 3 carbon atoms which may be substituted with a halogen atom, an ester bond, an amide bond, and a sulfide bond. Structure.)

Moreover, the film with a conductive layer according to the present invention is the above invention, wherein the polyimide is represented by the following general formula (9) in at least one of the acid dianhydride residue and the diamine residue constituting the polyimide. It contains the repeating structure represented by these, It is characterized by the above-mentioned.

(In the general formula (9), R ²³ and R ²⁴ each independently represents a monovalent organic group having 1 to 20 carbon atoms. M is an integer of 3 to 200.)

Further, the film with a conductive layer according to the present invention is characterized in that, in the above invention, the polyimide contains a triamine skeleton.

Moreover, the film with a conductive layer according to the present invention is characterized in that, in the above invention, the gas barrier layer includes at least one of silicon oxide, silicon nitride, silicon oxynitride, and silicon carbonitride. And

In the film with a conductive layer according to the present invention, the gas barrier layer may be SiOxNy (where x and y are 0 <x ≦ 1, 0.55 ≦ y ≦ 1 and 0 ≦ x / y ≦ 1). It is a value which satisfy | fills.) The component represented by this is included.

Moreover, the film with a conductive layer according to the present invention is the above-described invention, wherein the gas barrier layer is an inorganic film laminated in two or more layers, and the layer in contact with the conductive layer in the inorganic film is SiOz (z Is a value satisfying 0.5 ≦ z ≦ 2)).

The conductive layer-attached film according to the present invention is characterized in that, in the above invention, the conductive particles are silver particles.

Moreover, the film with a conductive layer according to the present invention is formed from an alkali-soluble resin including a cardo resin having two or more structures represented by the following structural formula (10) on the conductive layer in the above invention. And an insulating layer.

Further, a touch panel according to the present invention includes the film with a conductive layer according to any one of the above inventions, and the conductive layer is a wiring layer.

The method for producing a film with a conductive layer according to the present invention includes a resin film forming step of forming a resin film containing polyimide on a support substrate, and a gas barrier layer forming step of forming a gas barrier layer on the resin film. And a conductive layer forming step of forming a conductive layer on the gas barrier layer, and a peeling step of peeling the resin film from the support substrate.

In the method for producing a film with a conductive layer according to the present invention, in the above invention, the conductive layer forming step uses a conductive composition containing conductive particles having a coating layer on at least a part of the surface. The conductive layer is formed.

Further, in the method for producing a film with a conductive layer according to the present invention, in the above invention, the resin film forming step is performed at 300 ° C. in an atmosphere having an oxygen concentration of 1000 ppm or less. The resin film is formed by heating at a temperature of 500 ° C. or lower, and in the conductive layer forming step, the conductive composition on the gas barrier layer is heated to 100 ° C. or higher in an atmosphere having an oxygen concentration of 15% or higher. The conductive layer is formed by heating at a temperature of 300 ° C. or lower.

Moreover, the manufacturing method of the touchscreen which concerns on this invention is a manufacturing method of the touchscreen using the manufacturing method of the film with a conductive layer as described in any one of said invention, Comprising: The said conductive layer formation process is the said electroconductivity. It is a step of forming a wiring layer as a layer.

ADVANTAGE OF THE INVENTION According to this invention, providing the film with a conductive layer which suppressed yellowing at the time of conductive layer formation, and was excellent in the dimensional accuracy of a conductive layer, a touch panel, the manufacturing method of a film with a conductive layer, and the manufacturing method of a touch panel are provided. There is an effect that can be done.

FIG. 1 is a schematic cross-sectional view showing a configuration example of a film with a conductive layer according to an embodiment of the present invention. FIG. 2 is a plan view showing a configuration example of a touch panel including a film with a conductive layer according to an embodiment of the present invention according to the embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing a configuration example of a touch panel including a film with a conductive layer according to an embodiment of the present invention. FIG. 4 is a process diagram showing an example of a method for manufacturing a touch panel including a film with a conductive layer according to an embodiment of the present invention.

Hereinafter, preferred embodiments of a film with a conductive layer, a touch panel, a method for producing a film with a conductive layer, and a method for producing a touch panel according to the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and can be implemented with various modifications according to the purpose and application.

<Film with conductive layer>
The film with a conductive layer according to the embodiment of the present invention is a film with a conductive layer having a conductive layer containing conductive particles on a resin film containing polyimide, and between the resin film and the conductive layer. Has a gas barrier layer. In the present embodiment, this resin film contains polyimide having an imide group concentration defined by the following formula (I) of 20.0% or more and 36.5% or less.
(Molecular weight of the imide group) / (Molecular weight of the repeating unit of polyimide) x 100 [%]
... (I)

FIG. 1 is a schematic cross-sectional view showing a configuration example of a film with a conductive layer according to an embodiment of the present invention. As shown in FIG. 1, the film 11 with a conductive layer includes a resin film 1, a gas barrier layer 2, and a conductive layer 3A. As described above, the resin film 1 is a polyimide resin film containing polyimide in which the imide group concentration defined by the formula (I) is 20.0% or more and 36.5% or less. The gas barrier layer 2 is formed on the resin film 1. The conductive layer 3 </ b> A is a conductive layer containing conductive particles, and is formed on the gas barrier layer 2.

In the film 11 with a conductive layer having such a configuration, the gas barrier layer 2 is interposed between the resin film 1 and the conductive layer 3A as shown in FIG. Thereby, the gas barrier layer 2 can prevent the oxygen at the time of heat-forming the conductive layer 3 </ b> A from coming into contact with the resin film 1. As a result, a decrease in color of the resin film 1 due to heating in the presence of oxygen (for example, a decrease in color due to yellowing) is suppressed. Although not particularly shown in FIG. 1, the film 11 with a conductive layer may further include an insulating layer on the conductive layer 3A.

FIG. 2 is a plan view showing a configuration example of a touch panel including a film with a conductive layer according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing a configuration example of a touch panel including a film with a conductive layer according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of the touch panel 10 taken along a broken line I-I ′ in FIG. This touch panel 10 is a touch panel including the film 11 with a conductive layer according to the present embodiment. As shown in FIGS. 2 and 3, the touch panel 10 includes a resin film 1, a gas barrier layer 2, a first wiring layer 3, a first insulating layer 4, a second wiring layer 5, and a second wiring layer. And an insulating layer 6.

The resin film 1 and the gas barrier layer 2 are the same as the film 11 with a conductive layer shown in FIG. The first wiring layer 3 is an application example of the conductive layer 3A of the film 11 with the conductive layer. That is, the touch panel 10 includes the resin film 1, the gas barrier layer 2, and the first wiring layer 3 as the film 11 with a conductive layer.

2 and 3, the first wiring layer 3 is formed on the gas barrier layer 2 on the resin film 1 so as to form a desired wiring pattern. The first insulating layer 4 is formed on the first wiring layer 3 and the gas barrier layer 2 so as to cover the first wiring layer 3 other than the electrode portion. The second wiring layer 5 is a wiring layer different from the first wiring layer 3 and is formed on the first insulating layer 4 and the gas barrier layer 2 so as to form a desired wiring pattern. In the touch panel 10, the first wiring layer 3 and the second wiring layer 5 are insulated by the first insulating layer 4. The second insulating layer 6 is formed on the second wiring layer 5 and the first insulating layer 4 so as to cover the second wiring layer 5 other than the electrode portion.

(Resin film (polyimide resin film))
The resin film (for example, the resin film 1 shown in FIG. 1) used for the film with a conductive layer according to the embodiment of the present invention has an imide group concentration defined by the above formula (I) of 20.0% or more and 36.36. Contains polyimide that is 5% or less.

Since polyimide is obtained by reacting diamine with tetracarboxylic dianhydride, the imide group concentration of the resulting polyimide decreases as the molecular weight of each monomer (diamine and tetracarboxylic dianhydride) increases. When the imide group concentration is lower than 20.0%, the interaction between polyimide molecules due to the imide group becomes weak, and the glass transition temperature (Tg) of the polyimide decreases. In a film with a conductive layer, if the glass transition temperature of a resin film (polyimide resin film) serving as a substrate is low, the resin film cannot withstand the heat applied during the formation of the gas barrier layer and the conductive layer. As a result, sufficient dimensional accuracy (for example, dimensional accuracy of the conductive layer) of the film with the conductive layer cannot be obtained. On the other hand, when the imide group concentration is higher than 36.5%, the interaction between the polyimide molecules due to the imide group becomes too strong, and the polyimide molecules are crystallized in the resin film. As a result, the visibility of the film with a conductive layer is deteriorated.

In the present invention, by setting the imide group concentration to a concentration within the range of 20.0% or more and 36.5% or less, a polyimide resin (resin film of a film with a conductive layer) having a balance between heat resistance and transparency can be obtained. (Polyimide constituting) can be obtained. The imide group concentration is a value obtained by calculation by the following method.

The molecular weight of the imide group part is the molecular weight of the (—CO—N—CO—) part contained in the polyimide repeating unit. The molecular weight per imide group is 70.03. Moreover, the molecular weight of the repeating unit of a polyimide is the molecular weight of the part originating in the tetracarboxylic dianhydride and diamine which comprise one repeating unit. From these facts, the imide group concentration can be calculated based on the above-described formula (I). When there are a plurality of repeating units in the polyimide, after obtaining the imide group concentration of each repeating unit, the value obtained by multiplying the contents of each repeating unit multiplied by each other is taken as the polyimide imide group concentration. .

For example, in the case of polyimide represented by the following structural formula (A), the molecular weight of the imide group portion is the molecular weight of a portion surrounded by a dotted line. In this case, the molecular weight of the imide group portion is 140.06 (= 70.03 × 2). The molecular weight of the repeating unit is 372.11. Therefore, the imide group concentration is 37.8% (= (140.06 / 372.11) × 100) based on the above-described formula (I).

Further, in the case of a polyimide represented by the following structural formula (B) having a plurality of repeating units, the imide group concentration of the repeating unit G1 is 37.8% (= (140.06) / (372.11) × 100). The imide group concentration of the repeating unit G2 is 23.4% (= (140.06) / (598.66) × 100) based on the formula (I) described above. Further, the content number m of the repeating unit G1 and the content number n of the repeating unit G2 are in a relationship of m: n = 90: 10. Therefore, the imide group concentration of polyimide is 36.4% (= 37.8% × 0.90 + 23.4% × 0.10).

In the present invention, the glass transition temperature (Tg) of the resin film containing polyimide is preferably 250 ° C. or higher. This is because deformation of the resin film is suppressed in the heating step when forming the gas barrier layer or conductive layer on the resin film, and as a result, the dimensional accuracy during processing of the conductive layer is further improved. . The glass transition temperature of the resin film containing polyimide is more preferably 300 ° C. or higher, and particularly preferably 350 ° C. or higher.

Examples of a method for measuring the glass transition temperature of the resin film include a measurement method using a thermomechanical analyzer (TMA method). In the present invention, a resin film piece having a film thickness of 10 μm to 20 μm, a width of 15 mm, a length of 30 mm is wound in the length direction, and a cylinder having a diameter of 3 mm and a height of 15 mm The inflection point of the TMA curve when this sample is heated in a compressed mode in a nitrogen stream at a temperature rising rate of 5 ° C./min is defined as the glass transition temperature of the resin film.

In this invention, it is preferable that the polyimide used for the resin film of the film with a conductive layer contains the structural unit represented by following General formula (1).

In the general formula (1), R ¹ is a monovalent or condensed polycyclic alicyclic structure, a tetravalent organic group having 4 to 40 carbon atoms, or an organic having a monocyclic alicyclic structure. A tetravalent organic group having 4 to 40 carbon atoms in which groups are linked to each other directly or via a crosslinked structure. R ² represents a divalent organic group having 4 to 40 carbon atoms.

When the polyimide contains the structural unit represented by the general formula (1), the thermal expansion coefficient (CTE) of the polyimide is lowered. Therefore, when polyimide is formed on a support substrate for a process such as formation of a conductive layer, the warp of the polyimide is reduced, and the dimensional accuracy can be improved in processing of the conductive layer.

R ¹ in the general formula (1) represents the structure of the acid component. In the alicyclic structure in R ¹ , some hydrogen atoms may be substituted with halogen. The acid dianhydride having an alicyclic structure is not particularly limited, but 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,4,5-cyclopentanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3 4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid Dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,2,3,4-cycloheptanetetracarboxylic dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic acid Anhydride, 3,4-dicarboxy-1-cyclohexylsuccinic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro- 1-naphthalene succinic dianhydride, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic dianhydride, bicyclo [4.3.0] nonane-2,4,7, 9-tetracarboxylic dianhydride, bicyclo [4.4.0] decane-2,4,7,9-tetracarboxylic dianhydride, bicyclo [4.4.0] decane-2,4,8, 10-tetracarboxylic dianhydride, tricyclo [6.3.0.0 <2,6>] undecane-3,5,9,11-tetracarboxylic dianhydride, bicyclo [2.2.2] octane -2,3,5,6-tetracarboxylic dianhydride, Cyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2.2.1] heptanetetracarboxylic dianhydride, bicyclo [2.2 .1] heptane-5-carboxymethyl-2,3,6-tricarboxylic dianhydride, 7-oxabicyclo [2.2.1] heptane-2,4,6,8-tetracarboxylic dianhydride, Octahydronaphthalene-1,2,6,7-tetracarboxylic dianhydride, tetradecahydroanthracene-1,2,8,9-tetracarboxylic dianhydride, 3,3 ′, 4,4′-dicyclo Hexanetetracarboxylic dianhydride, 3,3 ′, 4,4′-oxydicyclohexanetetracarboxylic dianhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3 -Cyclohexene-1,2- Carboxylic acid anhydrides, "RIKACID" (TM) BT-100 (trade names, manufactured by New Japan Chemical Co., Ltd.), and their derivatives, and the like.

R ¹ in the general formula (1) is preferably at least one selected from six structures represented by the following structural formulas (11) to (16).

Of these six structures, R ¹ is a structure represented by the following structural formulas (17) to (19) from the viewpoint of being commercially available and easy to obtain and the reactivity with the diamine compound. It is more preferable. Examples of acid dianhydrides that give these structures to R ¹ include 1S, 2S, 4R, 5R-cyclohexanetetracarboxylic dianhydride (for example, product name “PMDA” manufactured by Wako Pure Chemical Industries, Ltd.). -HH "), 1R, 2S, 4S, 5R-cyclohexanetetracarboxylic dianhydride (for example, product name" PMDA-HS "manufactured by Wako Pure Chemical Industries, Ltd.), 1,2,3,4-cyclobutane Tetracarboxylic dianhydride etc. are mentioned. In addition, these acid dianhydrides can be used individually or in combination of 2 or more types.

In general formula (1), ^{R 2} represents the structure of the diamine component. Examples of the diamine compound used in R ^2, is not particularly limited, aromatic diamine compounds, alicyclic diamine compounds, or aliphatic diamine compounds.

The aromatic diamine compound is not particularly limited, but 1,4-bis (4-aminophenoxy) benzene, m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, bis {4- (4-aminophenoxyphenyl)} sulfone, bis {4- (3-aminophenoxyphenyl)} sulfone, bis (4-aminophenoxy) biphenyl, bis {4- (4-aminophenoxy) phenyl} ether, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane 3-aminophenyl-4-aminobenzenesulfonate, 4-aminophenyl-4-a Roh benzenesulfonate or an alkyl group part of an aromatic ring of these compounds, an alkoxy group, and a diamine compound substituted with a halogen atom or the like.

The alicyclic diamine compound is not particularly limited, but is cyclobutanediamine, isophoronediamine, bicyclo [2.2.1] heptanebismethylamine, tricyclo [3.3.1.13,7] decane-1,3- Diamine, 1,2-cyclohexyldiamine, 1,3-cyclohexyldiamine, 1,4-cyclohexyldiamine, 4,4′-diaminodicyclohexylmethane, 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, 3, 3′-diethyl-4,4′-diaminodicyclohexylmethane, 3,3 ′, 5,5′-tetramethyl-4,4′-diaminodicyclohexylmethane, 3,3 ′, 5,5′-tetraethyl-4, 4'-diaminodicyclohexylmethane, 3,5-diethyl-3 ', 5'-dimethyl-4,4'- Aminodicyclohexylmethane, 4,4′-diaminodicyclohexyl ether, 3,3′-dimethyl-4,4′-diaminodicyclohexyl ether, 3,3′-diethyl-4,4′-diaminodicyclohexyl ether, 3,3 ′, 5,5′-tetramethyl-4,4′-diaminodicyclohexyl ether, 3,3 ′, 5,5′-tetraethyl-4,4′-diaminodicyclohexyl ether, 3,5-diethyl-3 ′, 5′- Dimethyl-4,4′-diaminodicyclohexyl ether, 2,2-bis (4-aminocyclohexyl) propane, 2,2-bis (3-methyl-4-aminocyclohexyl) propane, 2,2-bis (3-ethyl) -4-aminocyclohexyl) propane, 2,2-bis (3,5-dimethyl-4-aminocyclo) Xyl) propane, 2,2-bis (3,5-diethyl-4-aminocyclohexyl) propane, 2,2- (3,5-diethyl-3 ′, 5′-dimethyl-4,4′-diaminodicyclohexyl) Propane, 2,2'-bis (4-aminocyclohexyl) hexafluoropropane, 2,2'-dimethyl-4,4'-diaminobicyclohexane, 2,2'-bis (trifluoromethyl) -4,4 Examples include '-diaminobicyclohexane or diamine compounds in which a part of the aliphatic ring of these compounds is substituted with an alkyl group, an alkoxy group, a halogen atom, or the like.

The aliphatic diamine compound is not particularly limited, but ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1 Alkylenediamines such as 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, bis (aminomethyl) ether, bis (2-aminoethyl) ether, bis (3-aminopropyl) ether, etc. Ethylene glycol diamines, and 1,3-bis (3-aminopropyl) tetramethyldisiloxane, 1,3-bis (4-aminobutyl) tetramethyldisiloxane, α, ω-bis (3-aminopropyl) poly Examples include siloxane diamines such as dimethylsiloxane.

These aromatic diamine compounds, alicyclic diamine compounds, and aliphatic diamine compounds can be used alone or in combination of two or more.

In the present invention, the polyimide used for the resin film of the film with a conductive layer preferably contains a structural unit represented by the following general formula (2).

In the general formula (2), R ³ represents a tetravalent organic group having 4 to 40 carbon atoms. R ⁴ has a monocyclic or condensed polycyclic alicyclic structure, a divalent organic group having 4 to 40 carbon atoms, or an organic group having a monocyclic alicyclic structure directly or has a crosslinked structure. A divalent organic group having 4 to 40 carbon atoms or a divalent organic group represented by the following general formula (3), which are connected to each other.

In the general formula (3), X ¹ is a divalent hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a halogen atom. Ar ¹ and Ar ² each independently represents a divalent aromatic group having 4 to 40 carbon atoms.

When the polyimide contains the structural unit represented by the general formula (2), the thermal expansion coefficient of the polyimide is lowered. Therefore, when polyimide is formed on a support substrate for a process such as formation of a conductive layer, the warp of the polyimide is reduced, and the dimensional accuracy can be improved in processing of the conductive layer.

R ³ in the general formula (2) represents the structure of the acid component. As the acid dianhydride used for R ^3, but are not limited to, in addition to the acid dianhydride having an alicyclic structure described above, the aromatic dianhydride and aliphatic acid dianhydride.

The aromatic dianhydride is not particularly limited, but pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′, 4′-biphenyl Tetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-terphenyltetracarboxylic dianhydride, 3,3 ′, 4 , 4′-oxyphthalic dianhydride, 2,3,3 ′, 4′-oxyphthalic dianhydride, 2,3,2 ′, 3′-oxyphthalic dianhydride, diphenylsulfone-3,3 ′, 4,4′-tetracarboxylic dianhydride, benzophenone-3,3 ′, 4,4′-tetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propyl Bread dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (3,4-di Carboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (1,3-dioxo-1,3- Dihydroisobenzfuran-5-carboxylic acid) 1,4-phenylene, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2, 2-bi (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 2,2-bis (4- (3,4-dicarboxyphenoxy) phenyl) hexafluoropropane dianhydride, 2,2-bis (4- (3,4-Dicarboxybenzoyloxy) phenyl) hexafluoropropane dianhydride, 1,6-difluoropromellitic dianhydride, 1-trifluoromethylpyromellitic dianhydride, 1,6-ditrifluoromethyl Pyromellitic dianhydride, 2,2′-bis (trifluoromethyl) -4,4′-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride, 9,9-bis [4- (3 4-Dicarboxyphenoxy) phenyl] fluorene dianhydride, 4,4 ′-((9H-fluorenyl) bis (4,1-phenyleneoxycarbonyl)) di Examples thereof include phthalic dianhydrides, aromatic tetracarboxylic dianhydrides such as “Licacid” (registered trademark) TMEG-100 (trade name, manufactured by Shin Nippon Rika Co., Ltd.), and derivatives thereof.

The aliphatic acid dianhydride is not particularly limited, but 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride, and derivatives thereof Etc.

In the general formula (2), R ⁴ represents the structure of the diamine component. The diamine compound used for R ⁴ , that is, the diamine compound having an alicyclic structure is not particularly limited, but is cyclobutanediamine, isophoronediamine, bicyclo [2.2.1] heptanebismethylamine, tricyclo [3.3. 1.13,7] decane-1,3-diamine, 1,2-cyclohexyldiamine, 1,3-cyclohexyldiamine, 1,4-cyclohexyldiamine, 4,4'-diaminodicyclohexylmethane, 3,3'-dimethyl -4,4'-diaminodicyclohexylmethane, 3,3'-diethyl-4,4'-diaminodicyclohexylmethane, 3,3 ', 5,5'-tetramethyl-4,4'-diaminodicyclohexylmethane, 3, 3 ', 5,5'-tetraethyl-4,4'-diaminodicyclohexylmethane, 3,5-diethi -3 ', 5'-dimethyl-4,4'-diaminodicyclohexylmethane, 4,4'-diaminodicyclohexyl ether, 3,3'-dimethyl-4,4'-diaminodicyclohexyl ether, 3,3'-diethyl- 4,4'-diaminodicyclohexyl ether, 3,3 ', 5,5'-tetramethyl-4,4'-diaminodicyclohexyl ether, 3,3', 5,5'-tetraethyl-4,4'-diaminodicyclohexyl Ether, 3,5-diethyl-3 ′, 5′-dimethyl-4,4′-diaminodicyclohexyl ether, 2,2-bis (4-aminocyclohexyl) propane, 2,2-bis (3-methyl-4- Aminocyclohexyl) propane, 2,2-bis (3-ethyl-4-aminocyclohexyl) propane, 2,2-bis (3,5-dimethyl-4- Aminocyclohexyl) propane, 2,2-bis (3,5-diethyl-4-aminocyclohexyl) propane, 2,2- (3,5-diethyl-3 ′, 5′-dimethyl-4,4′-diaminodicyclohexyl Propane, 2,2'-bis (4-aminocyclohexyl) hexafluoropropane, 2,2'-dimethyl-4,4'-diaminobicyclohexane, 2,2'-bis (trifluoromethyl) -4, Examples thereof include 4′-diaminobicyclohexane, and diamine compounds in which a part of the aliphatic ring of these compounds is substituted with an alkyl group, an alkoxy group, a halogen atom, or the like.

The diamine that gives the structure represented by the general formula (3) is not particularly limited, but 2,2-bis (3-aminophenyl) propane, 2,2-bis [4- (4-aminophenoxy) phenyl] Propane, 2,2-bis (3-aminophenyl) hexafluoropropane, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, 2,2-bis [3- (3-aminobenzamide) -4-hydroxyphenyl] hexafluoropropane and the like.

In the present invention, the polyimide used for the resin film of the film with a conductive layer has a structural unit represented by the following general formula (4) as a main component and the structural unit represented by the following general formula (5). It is preferable to contain 5 mol% or more and 30 mol% or less of the total structural unit of polyimide.

In the general formulas (4) and (5), R ¹ is a monovalent or condensed polycyclic alicyclic structure, a tetravalent organic group having 4 to 40 carbon atoms, or a monocyclic alicyclic ring. A tetravalent organic group having 4 to 40 carbon atoms in which organic groups having a structure are connected to each other directly or via a crosslinked structure. R ¹³ represents a divalent organic group represented by the following general formula (6). R ¹⁴ is a structure represented by the following structural formula (7) or the following structural formula (8).

In the general formula (6), R ¹⁵ to R ²² each independently represent a hydrogen atom, a halogen atom, or a monovalent organic group having 1 to 3 carbon atoms that may be substituted with a halogen atom. X ² is selected from a direct bond, an oxygen atom, a sulfur atom, a sulfonyl group, a divalent organic group having 1 to 3 carbon atoms which may be substituted with a halogen atom, an ester bond, an amide bond, and a sulfide bond. It is a structure.

In addition, the oxazole ring in the structural formula (8) is generated by dehydration ring closure from the structure represented by the structural formula (7).

Here, “having the structural unit represented by the general formula (4) as a main component” means that the structural unit represented by the general formula (4) is 50 mol% in the total amount of all structural units of polyimide. It means having the above. When polyimide has the structural unit represented by the general formula (4) as a main component, the thermal expansion coefficient of polyimide is lowered. Therefore, when polyimide is formed on a support substrate for a process such as formation of a conductive layer, the warp of the polyimide is reduced, and the dimensional accuracy can be improved in processing of the conductive layer.

The total amount of all structural units of polyimide is specifically the total amount (mol basis) of the structural units represented by the general formula (4) and the general formula (5). When the polyimide contains a structure other than the structural units represented by the general formula (4) and the general formula (5), the total amount is a structural unit represented by the general formula (4) and the general formula (5). And the total amount (mol basis) of the structure other than the structural unit represented by the general formula (4) and the general formula (5).

In the present invention, the content of the structural unit represented by the general formula (4) is more preferably 70 mol% or more of the total structural unit of polyimide.

In addition, the polyimide contains the structural unit represented by the general formula (5) in an amount of 5 mol% or more and 30 mol% or less of the entire structural unit, thereby keeping the thermal expansion coefficient of the polyimide low while improving the transparency of the resin film. Can do. Thereby, the color of a film with a conductive layer (and a touch panel including this) can be improved while maintaining the pattern processability of the conductive layer. The content of the structural unit (repeating structural unit) represented by the general formula (5) in the polyimide is more preferably 10 mol% or more and 25 mol% or less of the total structural unit of the polyimide.

R ¹ in the general formula (4) and the general formula (5) is the same as R ¹ in the general formula (1) represents a structure of an acid component having an alicyclic structure. Preferred specific examples of R ¹ are as described above. R ¹³ in the general formula (4) and R ¹⁴ in the general formula (5) represent the structure of the diamine component.

The diamine that gives the structure represented by the general formula (6) to R ¹³ is not particularly limited, but 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenylmethane, 4, 4'-diaminodiphenylmethane, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis (3-amino-4 -Methylphenyl) hexafluoropropane, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, benzidine, 2,2 '-Bis (trifluoromethyl) benzidine, 3,3'-bis (trifluoromethyl) ) Benzidine, 2,2'-dimethylbenzidine, 3,3'-dimethylbenzidine, 2,2 ', 3,3'-tetramethylbenzidine, 4,4-diaminobenzanilide, 4-aminobenzoic acid-4-amino Phenyl, 3,4-diaminobenzanilide, 4,4-diaminobenzophenone, 3,3-diaminobenzophenone, or diamine compounds obtained by substituting a part of the aromatic ring of these compounds with alkyl groups, alkoxy groups, halogen atoms, etc. Is mentioned.

R ¹³ is selected from, for example, four structures represented by the following structural formulas (20) to (23) from the viewpoint of availability, transparency, and reduction of the thermal expansion coefficient of polyimide. It is preferable that there are more types.

In the present invention, the polyimide used for the resin film of the film with a conductive layer may contain other structural units as long as the effects of the present invention are not hindered. Examples of other structural units include polyimide, which is a polycyclic amide dehydration ring, polybenzoxazole, a polyhydroxyamide dehydration ring closure, and the like. Examples of the acid dianhydride used for the other structural unit include the above-mentioned aromatic acid dianhydride or aliphatic acid dianhydride.

In the present invention, the polyimide used for the resin film of the film with a conductive layer is represented by the following general formula (9) in at least one of the acid dianhydride residue and the diamine residue constituting the polyimide. It is preferable to contain a repeating structure.

In the general formula (9), R ²³ and R ²⁴ each independently represent a monovalent organic group having 1 to 20 carbon atoms. m is an integer of 3 to 200.

By including the structure represented by the general formula (9) in at least one of the acid dianhydride residue and the diamine residue, the polyimide is used as a support substrate for a process such as forming a conductive layer. When the film is formed on the top, the residual stress of the polyimide resin film is reduced. Therefore, the warp of the polyimide is reduced, and the dimensional accuracy can be improved in the processing of the conductive layer.

By the way, in a film with a conductive layer, there is a problem that static electricity is generated on the film and disconnection due to electrostatic discharge (ESD) occurs. On the other hand, since the polyimide including the structure represented by the general formula (9) has a low dielectric constant, the film with a conductive layer including the resin film including such a polyimide is used in a device such as a touch panel using the polyimide. Therefore, it is difficult to accumulate charges on the substrate, and ESD resistance is increased. Therefore, it is preferable that the polyimide used for the resin film of the film with a conductive layer includes a repeating structure represented by the general formula (9) as described above.

Examples of the monovalent organic group having 1 to 20 carbon atoms represented by R ²³ and R ²⁴ in the general formula (9) include, for example, a monovalent hydrocarbon group having 1 to 20 carbon atoms and a group having 1 to 20 carbon atoms. A monovalent aminoalkyl group, an alkoxy group, an epoxy group, and the like can be given.

Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms. The alkyl group having 1 to 20 carbon atoms is preferably an alkyl group having 1 to 10 carbon atoms. Specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, t- A butyl group, a pentyl group, a hexyl group, etc. are mentioned. The cycloalkyl group having 3 to 20 carbon atoms is preferably a cycloalkyl group having 3 to 10 carbon atoms, and specific examples include a cyclopentyl group and a cyclohexyl group. The aryl group having 6 to 20 carbon atoms is preferably an aryl group having 6 to 12 carbon atoms, and specific examples thereof include a phenyl group, a tolyl group, and a naphthyl group.

Examples of the monovalent alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, propoxy group, isopropyloxy group, butoxy group, phenoxy group, propenyloxy group, and cyclohexyloxy group.

Among these, R ²³ and R ²⁴ are preferably a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or an aromatic group having 6 to 10 carbon atoms. This is because the resulting polyimide resin film has higher heat resistance and lower residual stress. Here, the monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms is particularly preferably a methyl group. The aromatic group having 6 to 10 carbon atoms is particularly preferably a phenyl group.

M in the general formula (9) is preferably an integer of 10 to 200, more preferably an integer of 20 to 150, still more preferably an integer of 30 to 100, and particularly preferably an integer of 35 to 80. It is. When m is 3 or more, the residual stress of the polyimide resin film tends to be reduced. When m is 200 or less, the cloudiness of the varnish which consists of a polyimide precursor and a solvent which is a composition for obtaining a polyimide can be suppressed.

Specific examples of the acid dianhydride having a repeating structure represented by the general formula (9) are not particularly limited, but X22-168AS (manufactured by Shin-Etsu Chemical Co., Ltd., number average molecular weight 1,000), X22-168A (Shin-Etsu) Chemical Company, number average molecular weight 2,000), X22-168B (manufactured by Shin-Etsu Chemical Co., Ltd., number average molecular weight 3,200), X22-168-P5-8 (manufactured by Shin-Etsu Chemical Co., Ltd., number average molecular weight 4,200), DMS-Z21 (manufactured by Gerest, number average molecular weight 600 to 800) and the like can be mentioned.

Specific examples of the diamine having a repeating structure represented by the general formula (9) are not particularly limited, but both terminal amino-modified methylphenyl silicone (manufactured by Shin-Etsu Chemical Co., Ltd .; X22-1660B-3 (number average molecular weight 4,400 ), X22-9409 (number average molecular weight 1,300)), both-end amino-modified dimethyl silicone (manufactured by Shin-Etsu Chemical Co., Ltd .; X22-161A (number average molecular weight 1,600), X22-161B (number average molecular weight 3,000)) KF8012 (number average molecular weight 4,400), manufactured by Toray Dow Corning; BY16-835U (number average molecular weight 900), manufactured by Chisso; Silaplane FM3311 (number average molecular weight 1000)).

In the present invention, the polyimide used for the resin film of the film with a conductive layer preferably contains a triamine skeleton. When the polyimide contains a triamine skeleton, the toughness of the polyimide can be improved and the yield of the subsequent process can be improved.

Specific examples of the triamine compound include those having no aliphatic group, 2,4,4′-triaminodiphenyl ether (TAPE), 1,3,5-tris (4-aminophenoxy) benzene (TAPOB), Examples thereof include tris (4-aminophenyl) amine, 1,3,5-tris (4-aminophenyl) benzene, 3,4,4′-triaminodiphenyl ether and the like. Specific examples of triamine compounds include tris (2-aminoethyl) amine (TAEA), tris (3-aminopropyl) amine, and the like having aliphatic groups. Of these, 2,4,4'-triaminodiphenyl ether and 1,3,5-tris (4-aminophenoxy) benzene are preferably used from the viewpoint of improving heat resistance.

The thickness of the resin film used for the film with a conductive layer of the present invention is preferably 1 μm or more from the viewpoint of improving the toughness of the film with a conductive layer (and thus the toughness of the touch panel), and is preferably 2 μm or more. More preferably, it is 5 μm or more. On the other hand, from the viewpoint of further improving the transparency of the film with a conductive layer, the thickness of the resin film is preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 30 μm or less.

The transmittance at a wavelength of 450 nm of the resin film used for the film with a conductive layer of the present invention is preferably 85% or more from the viewpoint of improving the image quality of the touch panel. Further, the transmittance at a wavelength of 450 nm of the resin film after heat treatment at 150 to 350 ° C. is preferably 80% or more.

The resin film used for the film with a conductive layer of the present invention is prepared by adding an organic solvent, a surfactant, a leveling agent, an adhesion improver, a viscosity modifier, an antioxidant, an inorganic pigment to the polyimide or a precursor thereof as necessary. It can be formed using a resin composition formed by blending organic pigments, dyes and the like.

One of the methods for obtaining a resin film used in the film with a conductive layer of the present invention is to imide ring closure of polyamic acid which is a precursor corresponding to the polyimide to be obtained. It does not specifically limit as a method of imidation, Thermal imidation and chemical imidation are mentioned. Among these, thermal imidization is preferable from the viewpoint of heat resistance of the polyimide resin film and transparency in the visible light region.

Polyimide precursors such as polyamic acid, polyamic acid ester, and polyamic acid silyl ester can be synthesized by a polymerization reaction between a diamine compound and an acid dianhydride or a derivative thereof. Examples of the acid dianhydride derivative include tetracarboxylic acid of acid dianhydride, monoester, diester, triester or tetraester of the tetracarboxylic acid, and acid chloride. Specifically, acid dianhydride derivatives having a structure esterified with methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, etc. Is mentioned. The reaction method of the polymerization reaction is not particularly limited as long as the target polyimide precursor can be produced, and a known reaction method can be used.

As a specific reaction method of the above polymerization reaction, a predetermined amount of all diamine components and a solvent are charged into a reactor, and after dissolving the diamine, a predetermined amount of acid dianhydride component is charged at room temperature to 80 ° C. Examples thereof include a method of stirring for 0.5 to 30 hours.

In the present invention, the polyimide and polyimide precursor used for the resin film of the film with a conductive layer may be sealed at both ends with a terminal sealing agent in order to adjust the molecular weight to a preferred range. Examples of the terminal blocking agent that reacts with the acid dianhydride include monoamines and monohydric alcohols. Examples of the end-capping agent that reacts with the diamine compound include acid anhydrides, monocarboxylic acids, monoacid chloride compounds, monoactive ester compounds, dicarbonates, and vinyl ethers. Moreover, various organic groups can be introduce | transduced as a terminal group in these both terminal by making terminal blocker react with both terminals of a polyimide or a polyimide precursor. A well-known compound can be used for terminal blocker.

The introduction ratio of the terminal blocking agent on the acid anhydride group side is preferably in the range of 0.1 to 60 mol%, preferably in the range of 0.5 to 50 mol%, relative to the acid dianhydride component. It is more preferable that The introduction ratio of the terminal blocking agent on the amino group side is preferably in the range of 0.1 to 100 mol%, and preferably in the range of 0.5 to 70 mol% with respect to the diamine component. Is more preferable. You may introduce | transduce a several different terminal group into these both terminal by making a some terminal blocker react with the both terminal of a polyimide or a polyimide precursor.

The end sealant introduced into the polyimide precursor or polyimide can be easily detected by the following method. For example, a polymer into which a terminal blocking agent has been introduced is dissolved in an acidic solution and decomposed into an amine component and an acid anhydride component that are constituent units of the polymer. By measuring these using gas chromatography (GC) or NMR, the end-capping agent can be easily detected. In addition, if the polymer into which the end-capping agent is introduced is directly subjected to measurement of pyrolysis gas chromatography (PGC), infrared spectrum, ¹ H NMR spectrum, ¹³ C NMR spectrum, etc. It can be easily detected.

The composition for obtaining a resin film containing polyimide (hereinafter referred to as “polyimide resin composition”) may contain an appropriate component in addition to the polyimide or the polyimide precursor. The component that may be contained in the polyimide resin composition is not particularly limited, and examples thereof include an ultraviolet absorber, a thermal crosslinking agent, an inorganic filler, a surfactant, an internal release agent, and a colorant. Each of these can be a known compound.

In the present invention, for example, “a tetravalent organic group having 4 to 40 carbon atoms” means a tetravalent organic group having 4 to 40 carbon atoms. The same applies to other groups that define the number of carbon atoms.

(Gas barrier layer)
The film with a conductive layer according to the embodiment of the present invention has a gas barrier layer as exemplified by the gas barrier layer 2 illustrated in FIG. The gas barrier layer in the present invention refers to a layer that is formed on a resin film serving as a substrate and has a function of preventing direct contact between the resin film and environmental gases. When the conductive layer containing conductive particles is formed on the resin film, a high temperature of 200 ° C. or higher is applied to the resin film in the presence of oxygen. Therefore, if there is no gas barrier layer, yellowing due to thermal oxidation occurs in the resin film, resulting in deterioration of the color of the film with a conductive layer. By forming a gas barrier layer between the resin film and the conductive layer, it is possible to prevent the resin film and oxygen from contacting each other during heating in an oxygen atmosphere. Thus, a film with a conductive layer excellent in color without yellowing can be obtained.

The material constituting the gas barrier layer may be an organic material or an inorganic material as long as it prevents the permeation of oxygen when forming the conductive layer, but an inorganic material is preferable from the viewpoint of oxygen barrier properties. Examples of the inorganic material include metal oxide, metal nitride, metal oxynitride, and metal carbonitride. Examples of the metal element contained in these include aluminum (Al), silicon (Si), titanium (Ti), tin (Sn), zinc (Zn), zirconium (Zr), indium (In), and niobium (Nb). , Molybdenum (Mo), tantalum (Ta), calcium (Ca), and the like.

In particular, the gas barrier layer preferably contains at least one of silicon oxide, silicon nitride, silicon oxynitride, and silicon carbonitride. This is because by using these materials for forming the gas barrier layer, a uniform and dense gas barrier film can be easily obtained, and the oxygen barrier property of the gas barrier layer is further improved.

Also, from the viewpoint of further improving the oxygen barrier property, the gas barrier layer preferably contains a component represented by SiOxNy. x and y are values satisfying 0 <x ≦ 1, 0.55 ≦ y ≦ 1, and 0 ≦ x / y ≦ 1.

The gas barrier layer can be produced by a vapor deposition method in which a film is formed by depositing a material from the vapor phase, such as a sputtering method, a vacuum deposition method, an ion plating method, or a plasma CVD method. Among them, it is preferable to use a sputtering method or a plasma CVD method because a more uniform film having a high oxygen barrier property can be obtained.

The number of gas barrier layers is not limited, and may be only one layer or a multilayer of two or more layers. Examples of when the gas barrier layer is a multilayer film include a gas barrier layer in which the first layer is made of SiN and the second layer is made of SiO, a gas barrier layer in which the first layer is made of SiON and the second layer is made of SiO, etc. Is mentioned.

In the present invention, the gas barrier layer is an inorganic film laminated in two or more layers, and the layer in contact with the conductive layer among the inorganic films is SiOz (z is a value satisfying 0.5 ≦ z ≦ 2. It is preferable to form with the component represented by this. This is because the chemical resistance of the gas barrier layer at the time of processing the conductive layer (particularly during development using photolithography) is improved, and the pattern processability and dimensional accuracy of the conductive layer is improved, and the residue is suppressed. This is because an effect can be obtained.

The total thickness of the gas barrier layer is preferably 10 nm or more, and more preferably 50 nm or more, from the viewpoint of improving the oxygen barrier property. On the other hand, from the viewpoint of improving the bending resistance of the film with a conductive layer, the total thickness of the gas barrier layer is preferably 1 μm or less, and more preferably 200 nm or less.

(Conductive layer)
The film with a conductive layer according to the embodiment of the present invention has a conductive layer containing conductive particles as exemplified by the conductive layer 3A illustrated in FIG. The conductive layer preferably has a network structure with a line width of 0.1 to 9 μm. When the conductive layer has a network structure with a line width of 0.1 to 9 μm, the conductivity and visibility of the conductive layer can be improved. The line width of the network structure of the conductive layer is more preferably 0.5 μm or more, and further preferably 1 μm or more. On the other hand, the line width of the network structure of the conductive layer is more preferably 7 μm or less, and further preferably 6 μm or less.

The film thickness of the conductive layer is preferably 0.1 μm or more, more preferably 0.2 μm or more, and further preferably 0.3 μm or more. On the other hand, the thickness of the conductive layer is preferably 5 μm or less, more preferably 3 μm or less, and even more preferably 1 μm or less.

Examples of the conductive particles contained in the conductive layer include gold (Au), silver (Ag), copper (Cu), nickel (Ni), tin (Sn), bismuth (Bi), lead (Pb), zinc ( Examples thereof include metal particles such as Zn), palladium (Pd), platinum (Pt), aluminum (Al), tungsten (W), and molybdenum (Mo), and metal particles having carbon. The metal particles having carbon are, for example, a composite of carbon black and metal. Two or more of these may be used as the conductive particles. Among these, gold, silver, copper, nickel, tin, bismuth, lead, zinc, palladium, platinum or aluminum metal particles and carbon-containing metal particles are preferable, and silver particles are more preferable.

The primary particle diameter of the conductive particles is preferably 10 to 200 nm and more preferably 10 to 60 nm in order to form a fine conductive pattern having desired conductivity. Here, the primary particle size of the conductive particles is determined by observing the cross section of the conductive layer with a scanning electron microscope, selecting 100 particles at random, and measuring the primary particle size of each particle. It is calculated by taking the arithmetic average value of In addition, let the particle diameter of the primary particle of each particle | grain be an arithmetic mean value of the longest part and short part in a primary particle.

From the viewpoint of improving conductivity, the content of the conductive particles in the conductive layer is preferably 20% by mass or more, more preferably 50% by mass or more, and 65% by mass or more. Further preferred. On the other hand, the content of the conductive particles is preferably 95% by mass or less, and more preferably 90% by mass or less from the viewpoint of improving pattern processability.

The conductive layer preferably contains 0.1 to 80% by mass of an organic compound. When the conductive layer contains 0.1% by mass or more of the organic compound, the conductive layer can be given flexibility and the bending resistance of the conductive layer can be further improved. The content of the organic compound in the conductive layer is preferably 1% by mass or more, and more preferably 5% by mass or more. On the other hand, when the conductive layer contains 80% by mass or less of the organic compound, the conductivity can be improved. The content of the organic compound in the conductive layer is more preferably 50% by mass or less, and further preferably 35% by mass or less.

As the organic compound contained in the conductive layer, an alkali-soluble resin is preferable. As the alkali-soluble resin, a (meth) acrylic copolymer having a carboxyl group is preferable. Here, the (meth) acrylic copolymer refers to a copolymer of a (meth) acrylic monomer and another monomer.

Examples of the (meth) acrylic monomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) ) Acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, allyl (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate, butoxytriethylene glycol (meth) ) Acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycerol (meth) acrylate Relate, glycidyl (meth) acrylate, heptadecafluorodecyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, isodexyl (meth) acrylate, isooctyl (meth) ) Acrylate, lauryl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, methoxydiethylene glycol (meth) acrylate, octafluoropentyl (meth) acrylate, phenoxyethyl (meth) acrylate, stearyl ( (Meth) acrylate, trifluoroethyl (meth) acrylate, (meth) acrylamide, aminoethyl (meth) acrylate, phenyl ( Data) acrylate, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, thiophenol (meth) acrylate, benzyl mercaptan (meth) acrylate.

Examples of the other monomer include compounds having a carbon-carbon double bond. For example, aromatic vinyl compounds such as styrene, p-methylstyrene, o-methylstyrene, m-methylstyrene, α-methylstyrene, ( Amide unsaturated compounds such as (meth) acrylamide, N-methylol (meth) acrylamide, N-vinylpyrrolidone, (meth) acrylonitrile, allyl alcohol, vinyl acetate, cyclohexyl vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether, n- Examples include butyl vinyl ether, i-butyl vinyl ether, 2-hydroxyethyl vinyl ether, and 4-hydroxybutyl vinyl ether.

In order to introduce a carboxyl group imparting alkali solubility to the alkali-soluble resin, for example, (meth) acrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, acid anhydrides thereof, etc. ) A method of copolymerizing with an acrylic monomer.

The (meth) acrylic copolymer preferably has a carbon-carbon double bond in the side chain or molecular end from the viewpoint of increasing the speed of the curing reaction. Examples of the functional group having a carbon-carbon double bond include a vinyl group, an allyl group, and a (meth) acryl group.

The carboxylic acid equivalent of the alkali-soluble resin is preferably 400 to 1,000 g / mol. The carboxylic acid equivalent of the acrylic soluble resin can be calculated by measuring the acid value. In addition, the double bond equivalent of the alkali-soluble resin is preferably 150 to 10,000 g / mol because both hardness and crack resistance can be achieved at a high level. The double bond equivalent of the acrylic soluble resin can be calculated by measuring the iodine value.

The weight average molecular weight (Mw) of the alkali-soluble resin is preferably 1,000 to 100,000. By setting the weight average molecular weight within the above range, good coating characteristics of the alkali-soluble resin can be obtained, and the solubility of the alkali-soluble resin in the developer during pattern formation of the conductive layer can be improved. Here, the weight average molecular weight of the alkali-soluble resin refers to a polystyrene equivalent value measured by gel permeation chromatography (GPC).

The conductive layer may contain at least one of an organic tin compound and a metal chelate compound. When the conductive layer contains at least one of an organotin compound and a metal chelate compound, adhesion between the conductive layer and the gas barrier layer can be further improved. In particular, a metal chelate compound is more preferable because an adhesion improving effect can be obtained without applying an environmental load as compared with an organotin compound. Known compounds can be used as the organotin compound and the metal chelate compound.

The total content of the organotin compound and the metal chelate compound in the conductive layer is preferably 0.01% by mass or more and more preferably 0.05% by mass or more from the viewpoint of further improving the substrate adhesion. More preferably, it is more preferably 0.1% by mass or more. On the other hand, the total content of the organotin compound and the metal chelate compound is preferably 10% by mass or less from the viewpoint of improving the conductivity of the conductive layer and forming a finer pattern. More preferably, it is more preferably 3% by mass or less.

In addition to the conductive layer, at least one of a dispersant, a photopolymerization initiator, a monomer, a photoacid generator, a thermal acid generator, a solvent, a sensitizer, a pigment and a dye that absorb visible light, and adhesion improvement It is preferable to contain an agent, a surfactant, a polymerization inhibitor and the like.

In addition, the conductive layer in the present invention can be formed using a conductive composition. Examples of the components contained in the conductive composition include conductive particles, alkali-soluble resins, organotin compounds, metal chelate compounds, dispersants, photopolymerization initiators, monomers, photoacid generators, thermal acid generators, Examples thereof include at least one of a solvent, a sensitizer, a pigment and a dye that absorb visible light, an adhesion improver, a surfactant, or a polymerization inhibitor.

The conductive particles contained in the conductive composition preferably have a coating layer on at least a part of the particle surface. Thereby, the surface activity of the conductive particles can be reduced, and at least one of the reaction between the conductive particles and the reaction between the conductive particles and the organic component can be suppressed, and the dispersibility of the conductive particles can be improved. . Furthermore, even when photolithography is used for processing the conductive layer, scattering of exposure light can be suppressed and the conductive layer can be patterned with high accuracy. On the other hand, the coating layer on the surface of the conductive particles can be easily removed by heating at a high temperature of about 150 to 350 ° C. in the presence of oxygen. As a result, the conductive particles in the conductive composition can exhibit sufficient conductivity of the conductive layer.

The coating layer on the surface of the conductive particles preferably contains at least one of carbon and a carbon compound. When this coating layer contains at least one of carbon and a carbon compound, the dispersibility of the conductive particles in the conductive composition can be further improved.

As a method for forming a coating layer containing at least one of carbon and a carbon compound on the surface of the conductive particles, for example, a reactive gas having carbon such as methane gas is brought into contact with the conductive particles by a thermal plasma method. And the like (the method described in JP 2007-138287 A) and the like.

(Insulating layer)
The film with a conductive layer according to the embodiment of the present invention preferably has an insulating layer formed from an alkali-soluble resin on the conductive layer. The alkali-soluble in the present invention means that 0.1 g or more dissolves at 25 ° C. in a 0.045 mass% potassium hydroxide aqueous solution (100 g). An insulating layer formed of an alkali-soluble resin is preferable because it can be patterned by photolithography, thereby forming an opening for conduction of the conductive layer.

In addition, the film with a conductive layer according to the embodiment of the present invention preferably has an insulating layer formed on the conductive layer from an alkali-soluble resin containing the above-mentioned (meth) acrylic copolymer. This is because the flexibility of the insulating layer is increased by the (meth) acrylic copolymer in the alkali-soluble resin.

Furthermore, the film with a conductive layer according to the embodiment of the present invention is formed from an alkali-soluble resin containing a cardo resin having two or more structures represented by the following structural formula (10) on the conductive layer. It is preferable to have an insulating layer. This is because the cardo resin increases the hydrophobicity of the insulating layer, thereby improving the insulating property of the insulating layer.

The cardo resin can be obtained, for example, by further reacting a reaction product of an epoxy compound and an organic acid containing a radical polymerizable group with an acid dianhydride. Examples of the catalyst used for the reaction between an epoxy compound and an organic acid containing a radical polymerizable group and the reaction between the epoxy compound and acid dianhydride include, for example, an ammonium catalyst, an amine catalyst, a phosphorus catalyst, and a chromium catalyst. Etc. Examples of the ammonium-based catalyst include tetrabutylammonium acetate. Examples of the amine catalyst include 2,4,6-tris (dimethylaminomethyl) phenol or dimethylbenzylamine. Examples of the phosphorus catalyst include triphenylphosphine. Examples of the chromium-based catalyst include acetylacetonate chromium and chromium chloride. Moreover, as an epoxy compound, the following compounds are mentioned, for example.

Examples of the organic acid containing a radical polymerizable group include (meth) acrylic acid, mono (2- (meth) acryloyloxyethyl) succinate, mono (2- (meth) acryloyloxyethyl) phthalate, tetrahydrophthal Examples include acid mono (2- (meth) acryloyloxyethyl) and p-hydroxystyrene.

Examples of acid dianhydrides include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′, from the viewpoint of improving the chemical resistance of the cured film. 4-biphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride and the like are preferable. In addition, for the purpose of adjusting the molecular weight of the acid dianhydride, it is possible to use one obtained by replacing a part of the acid dianhydride with an acid anhydride.

Further, as the cardo resin having two or more structures represented by the structural formula (10), commercially available products can be preferably used. Examples of commercially available cardo resins include “WR-301 (trade name)” (manufactured by ADEKA), “V-259ME (trade name)” (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), “Ogsol CR-TR1 ( “Product Name)”, “Ogsol CR-TR2 (Product Name)”, “Ogsol CR-TR3 (Product Name)”, “Ogsol CR-TR4 (Product Name)”, “Ogsol CR-TR5 (Product Name)”, “ OGSOL CR-TR6 (trade name) "(manufactured by Osaka Gas Chemical Co., Ltd.).

The weight average molecular weights of the (meth) acrylic copolymer and the cardo resin are each preferably 2,000 or more from the viewpoint of improving coating properties. Moreover, these weight average molecular weights are each preferably 200,000 or less from the viewpoint of improving the solubility of the insulating layer in the developer in the pattern formation of the insulating layer. Here, a weight average molecular weight says the polystyrene conversion value measured by GPC.

When the insulating layer contains both the (meth) acrylic copolymer and the cardo resin, the weight average molecular weight (Mw (A1)) of the (meth) acrylic copolymer and the weight average molecular weight of the cardo resin The ratio (Mw (A2) / Mw (A1)) to (Mw (A2)) is preferably 0.14 or more from the viewpoint of suppressing layer separation and forming a uniform cured film. On the other hand, this ratio (Mw (A2) / Mw (A1)) is preferably 1.5 or less, and preferably 1.0 or less from the viewpoint of suppressing layer separation and forming a uniform cured film. It is more preferable.

The insulating layer in the present invention can be formed using an insulating composition containing an alkali-soluble resin. The content of the alkali-soluble resin contained in this insulating composition can be arbitrarily selected depending on the desired film thickness and application, but it is 10 parts by mass or more and 70 parts by mass with respect to 100 parts by mass of the solid content. Generally, it is as follows.

The above-mentioned insulating composition may contain a hindered amine light stabilizer. When said insulating composition contains a hindered amine light stabilizer, coloring of an insulating layer can be reduced more and the weather resistance of an insulating layer can be improved.

The above-mentioned insulating composition further includes a polyfunctional monomer, a curing agent, an ultraviolet absorber, a polymerization inhibitor, an adhesion improver, a solvent, a surfactant, a dissolution inhibitor, a stabilizer, an antifoaming agent, etc. It is also possible to contain these additives.

<Touch panel>
The touch panel according to the embodiment of the present invention includes the film with a conductive layer of the present invention as exemplified by the touch panel 10 illustrated in FIGS. In the present invention, the conductive layer of the film with a conductive layer is a wiring layer of the touch panel (for example, the first wiring layer 3 shown in FIGS. 2 and 3). As illustrated in FIGS. 2 and 3, the touch panel of the present invention has an insulating layer (first insulating layer) on the wiring layer (first wiring layer) on the gas barrier layer. A second wiring layer; The touch panel of the present invention may further include a second insulating layer on the side opposite to the surface in contact with the first insulating layer (that is, the upper surface side) of the second wiring layer. Since the touch panel of the present invention has the second insulating layer as described above, moisture in the atmosphere can be prevented from reaching the second wiring layer. As a result, the reliability of the touch panel can be further improved.

In the touch panel of the present invention, the first insulating layer and the second insulating layer may be made of the same material or different materials. Further, the film thicknesses of the first insulating layer and the second insulating layer are preferably 0.1 μm or more, and more preferably 0.5 μm or more, from the viewpoint of further improving the insulating properties. On the other hand, the film thicknesses of the first insulating layer and the second insulating layer are preferably 10 μm or less, and more preferably 3 μm or less, from the viewpoint of further improving their transparency.

The thickness of the film with a conductive layer applied to such a touch panel (that is, the film with a conductive layer according to the embodiment of the present invention) is preferably 1 to 40 μm. By setting the thickness of the film with a conductive layer to a thickness within this range, defects such as tearing and warping in the production process of the film with a conductive layer are suppressed, and the yield of the film with a conductive layer (and hence the yield of the touch panel) is reduced. Can be improved. Moreover, the followability of the shape with respect to bending at the time of using the touch panel of this invention as a flexible touch panel improves markedly. In the present invention, the thickness of the touch panel is more preferably 3 μm or more, and further preferably 5 μm or more. On the other hand, the thickness of the touch panel is more preferably 30 μm or less, and further preferably 25 μm or less.

The film with a conductive layer according to the embodiment of the present invention preferably has a b * value of −5 to 5 according to the L * a * b * color system defined by the International Lighting Commission 1976. By setting the value of b * to a value within this range, excessive chromaticity adjustment of a film with a conductive layer and a touch panel using the same becomes unnecessary, and as a result, the visibility of the display can be further improved. In the present invention, the value of b * is more preferably −4 to 4, and further preferably −3 to 3.

<Manufacturing method of touch panel including film with conductive layer>
The manufacturing method of the touchscreen containing the film with a conductive layer which concerns on embodiment of this invention uses this manufacturing method of a film with a conductive layer. This method for producing a film with a conductive layer includes at least a resin film forming step, a gas barrier layer forming step, a conductive layer forming step, and a peeling step. The resin film forming step is a step of forming a resin film containing polyimide on the support substrate. The gas barrier layer forming step is a step of forming a gas barrier layer on the resin film. The conductive layer forming step is a step of forming a conductive layer on the gas barrier layer. The peeling step is a step of peeling the resin film after the gas barrier layer and the conductive layer are formed from the support substrate. In this invention, the manufacturing method of a touch panel includes a wiring layer formation process as a conductive layer formation process in the manufacturing method of a film with a conductive layer. The wiring layer forming step is a step of forming a wiring layer as a conductive layer on the gas barrier layer.

FIG. 4 is a process diagram showing an example of a method for manufacturing a touch panel including a film with a conductive layer according to an embodiment of the present invention. In the method for manufacturing a touch panel in the present embodiment, a resin film forming step, a gas barrier layer forming step, a first wiring layer forming step, a first insulating layer forming step, a second wiring layer forming step, The second insulating layer forming step and the peeling step are sequentially performed in this order.

Specifically, first, in the resin film forming step, as shown in the state S1 in FIG. 4, the resin film 1 containing polyimide is formed on the support substrate 7. Next, in the gas barrier layer forming step, the gas barrier layer 2 is formed on the resin film 1 as shown in the state S2 of FIG. Next, in the first wiring layer forming step, the first wiring layer 3 is formed on the gas barrier layer 2 as shown in a state S3 in FIG. Next, in the first insulating layer forming step, the first insulating layer 4 is formed on the gas barrier layer 2 so as to cover the first wiring layer 3 as shown in a state S4 in FIG. . Next, in the second wiring layer formation step, on the first insulating layer 4 (on the gas barrier layer 2 and the first insulating layer 4 in the present embodiment) as shown in the state S5 in FIG. A second wiring layer 5 is formed. Next, in the second insulating layer forming step, the second insulating layer 6 is formed on the gas barrier layer 2 so as to cover the second wiring layer 5 as shown in a state S6 in FIG. . Thereafter, in the peeling step, as shown in a state S7 in FIG. 4, the laminated structure of the resin film 1 and the gas barrier layer 2 is cut at the cut end face 8. Next, the resin film 1 of this laminated structure is mechanically peeled from the support substrate 7. In this way, the touch panel 10 is obtained. Hereinafter, each of these steps will be described in detail.

(Resin film forming process)
The resin film forming step is a step of forming the resin film 1 containing polyimide on the support substrate 7 as described above. The resin film forming step includes a coating step of applying the polyimide resin composition described above on the support substrate 7, a prebaking step of drying the polyimide resin composition on the support substrate 7, and a polyimide resin composition after drying. And a curing step for curing.

Examples of the support substrate 7 include a silicon wafer, a ceramic substrate, and an organic substrate. Examples of the ceramic substrate include glass substrates such as soda glass, non-alkali glass, borosilicate glass, and quartz glass, alumina substrates, aluminum nitride substrates, and silicon carbide substrates. Suitable examples of the organic substrate include an epoxy substrate, a polyetherimide resin substrate, a polyether ketone resin substrate, a polysulfone resin substrate, a polyimide film, and a polyester film.

Examples of the method for applying the polyimide resin composition onto the support substrate 7 include application using a spin coater, bar coater, blade coater, roll coater, die coater, calendar coater, meniscus coater, screen printing, spray coating, and dip. A coat etc. are mentioned.

Examples of the heating method in the pre-bake process and the curing process include a hot plate, a hot air dryer (oven), vacuum drying, vacuum drying, or heating by infrared irradiation.

The pre-baking temperature and time of the polyimide resin composition in the pre-baking step may be appropriately determined depending on the composition of the target polyimide resin composition and the film thickness of the coating film to be dried (polyimide resin composition coating film). For example, in the prebaking step in the present invention, it is preferable to heat the coating film at a temperature range of 50 to 150 ° C. for 10 seconds to 30 minutes.

The curing atmosphere, temperature and time of the polyimide resin composition in the curing step may be appropriately determined depending on the composition of the target polyimide resin composition and the film thickness of the coating film to be cured (polyimide resin composition coating film). . From the viewpoint of suppressing yellowing of the film due to heating, in this curing step, the polyimide resin composition coating film on the support substrate 7 is heated to a temperature of 300 ° C. or more and 500 ° C. or less in an atmosphere having an oxygen concentration of 1000 ppm or less. It is preferable to form the resin film 1 by heating for 5 to 180 minutes.

(Gas barrier layer formation process)
The gas barrier layer forming step is a step of forming the gas barrier layer 2 on the resin film 1 as described above. As a method for forming the gas barrier layer 2 in this gas barrier layer forming step, for example, a gas phase in which a film is formed by depositing a material from the gas phase, such as a sputtering method, a vacuum evaporation method, an ion plating method, or a plasma CVD method. Deposition methods are mentioned. Among them, it is preferable to use a sputtering method or a plasma CVD method because a more uniform film (gas barrier layer 2) having a high oxygen barrier property can be obtained.

Since the polyimide resin preferably used for the resin film 1 in the present invention has a high glass transition temperature, it is possible to increase the substrate temperature (the temperature of the support substrate 7) when the gas barrier layer 2 is formed. Since the crystallinity of the gas barrier layer 2 is improved as the substrate temperature is higher, the gas barrier performance is improved. On the other hand, if the film forming temperature of the gas barrier layer 2 is too high, the bending resistance of the gas barrier layer 2 is lowered. From these viewpoints, the lower limit of the film forming temperature of the gas barrier layer 2 is preferably 80 ° C. or higher, and more preferably 100 ° C. or higher. Moreover, as an upper limit of the film forming temperature of the gas barrier layer 2, 400 degrees C or less is preferable and 350 degrees C or less is more preferable.

(First wiring layer formation process)
The first wiring layer forming step is a step of forming the first wiring layer 3 on the gas barrier layer 2 as described above. The first wiring layer forming step includes a coating step of coating the conductive composition on the gas barrier layer 2, a pre-baking step of drying the coating film of the conductive composition, and the dried coating film (pre-baking It is preferable to include a step of exposing and developing the film) to form a mesh pattern (exposure step and developing step) and a curing step of curing the pre-baked film formed with this pattern.

In particular, in the first wiring layer forming step, it is preferable to form the first wiring layer 3 using a conductive composition containing conductive particles having a coating layer on at least a part of the surface. This is because the conductive particles having the coating layer on at least a part of the surface suppress the scattering of the exposure light in the exposure process, whereby the wiring of the first wiring layer 3 can be patterned with high accuracy. Because.

In the first wiring layer forming step, as a method for applying the conductive composition on the gas barrier layer 2 and a drying method in the pre-bake step and the curing step for the coating film of the conductive composition, the resin described above is used. The method illustrated in the polyimide resin composition of a film formation process is mentioned.

As the light source used in the exposure process of the coating film of the conductive composition, for example, j-line, i-line, h-line, and g-line of a mercury lamp are preferable. As the developer used in the developing process of the coating film of the conductive composition, a known developer can be used. For example, as the developer, an alkaline aqueous solution in which an alkaline substance such as sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide (TMAH) is dissolved in water can be used. The developer may be obtained by appropriately adding a water-soluble organic solvent such as ethanol, γ-butyrolactone, dimethylformamide, N-methyl-2-pyrrolidone to the developer. Further, in order to obtain a better conductive pattern of the coating film of the conductive composition by this development step, a surfactant such as a nonionic surfactant is further added to the alkaline developer and the developer. It is also preferable to add such that the content thereof is 0.01 to 1% by mass.

The curing atmosphere, temperature and time of the conductive composition coating film (patterned pre-baked film) in the curing process are the same as the composition of the conductive composition and the coating film to be cured (conductive composition coating film). What is necessary is just to determine suitably with a film thickness. In this curing step, for example, it is preferable to heat the coating film of the conductive composition in the temperature range of 100 to 300 ° C. for 5 to 120 minutes. In particular, when the first wiring layer 3 contains conductive particles having a coating layer on the surface, in order to reliably remove the coating layer on the surface of the conductive particles and develop sufficient conductivity, In the curing step, the first wiring layer 3 is formed by heating the coating film of the conductive composition on the gas barrier layer 2 at a temperature of 100 ° C. or higher and 300 ° C. or lower in an atmosphere having an oxygen concentration of 15% or higher. It is preferable to do.

In particular, in order to obtain the touch panel 10 with little yellowing and excellent conductivity, in the manufacturing method of the touch panel 10, the polyimide resin composition is heated at a temperature of 300 ° C. or more and 500 ° C. or less in an atmosphere having an oxygen concentration of 1000 ppm or less. And forming a resin film 1 containing polyimide, and heating the conductive composition at a temperature of 100 ° C. to 300 ° C. in an atmosphere having an oxygen concentration of 15% or more to form a wiring layer (for example, a first layer) A wiring layer forming step of forming one wiring layer 3).

(First insulating layer forming step)
The first insulating layer forming step is a step of forming the first insulating layer 4 on the gas barrier layer 2 so as to cover the first wiring layer 3 as described above. The first insulating layer forming step includes a coating step of applying the above-described insulating composition onto the first wiring layer 3, a pre-baking step of drying the coating film of the insulating composition, and the dry coating. It is preferable to include a step (exposure step and development step) of forming a pattern by exposing and developing the film (pre-baked film) and a curing step of curing the pre-baked film (insulating film) formed with this pattern. Each step included in the first insulating layer forming step can be performed in the same manner as in the first wiring layer forming step described above.

(Second wiring layer forming step, second insulating layer forming step)
The second wiring layer forming step is a step of forming the second wiring layer 5 on the first insulating layer 4 as described above. In the second wiring layer forming step, the second wiring layer 5 can be formed by the same method as the first wiring layer 3 described above. The second insulating layer forming step is a step of forming the second insulating layer 6 so as to cover the second wiring layer 5 as described above. In the second insulating layer forming step, the second insulating layer 6 can be formed by the same method as the first insulating layer 4 described above.

In the manufacturing method of the touch panel 10, the second insulating layer 6 may not be formed on the second wiring layer 5, but the second insulating layer 6 is formed as described above. Is preferred. This is because, by forming the second insulating layer 6, it is possible to suppress moisture in the atmosphere from reaching the second wiring layer 5, thereby improving the moisture and heat resistance of the touch panel 10. It is.

(Peeling process)
As described above, the peeling step is a step of peeling the resin film 1 from the support substrate 7. As a method of peeling the resin film 1 containing polyimide from the support substrate 7 in this peeling step, for example, a method of peeling the resin film 1 by irradiating the resin film 1 from the back surface of the support substrate 7, a support substrate before taking out the touch panel 10 7 (hereinafter referred to as “support substrate with touch panel” as appropriate) is immersed in at least one of a solvent kept at 0 to 80 ° C. and purified water for 10 seconds to 10 hours, and the resin film 1 is removed from the upper surface. Examples of the method include cutting and mechanical peeling from the cut end face 8. Among these, considering the influence on the reliability of the touch panel 10, a method of mechanical peeling from the cut end surface 8 is preferable.

Moreover, the above-mentioned peeling process may be performed directly on the support substrate with a touch panel, or may be performed after a protective film or a transparent adhesive layer (OCA: Optical Clear Adhesive) is bonded to the support substrate with a touch panel. Furthermore, after bonding a support substrate with a touch panel to a member such as a display substrate via OCA, the resin film 1 is peeled off from the support substrate with a touch panel (that is, the touch panel 10 is taken out). It is preferable from the viewpoint of accuracy.

The touch panel according to the embodiment of the present invention has good visibility because the gas barrier layer prevents the resin film containing polyimide from being yellowed when the wiring layer is formed. Moreover, since the dimensional change of the resin film at the time of wiring layer formation is suppressed by a gas barrier layer, the touch panel excellent in dimensional accuracy can be provided. The touch panel according to the embodiment of the present invention is suitably used as a display member such as a smartphone or a tablet terminal.

<Method for producing film with conductive layer>
The method for producing a film with a conductive layer according to an embodiment of the present invention includes at least a resin film forming step, a gas barrier layer forming step, a conductive layer forming step, and a peeling step. Among these steps, the resin film forming step, the gas barrier layer forming step, and the peeling step are the same as the touch panel manufacturing method described above, as exemplified by the states S1, S3, and S7 in FIG. The conductive layer forming step is a step of forming a conductive layer on the gas barrier layer. This conductive layer forming step is the same as the step in which the first wiring layer in the first wiring layer forming step in the touch panel manufacturing method described above is replaced with a conductive layer. In the present invention, the conductive layer forming step is preferably a step of forming a conductive layer using a conductive composition containing conductive particles having a coating layer on at least a part of the surface. The conductive layer forming step is a step of forming the conductive layer by heating the conductive composition on the gas barrier layer at a temperature of 100 ° C. or higher and 300 ° C. or lower in an atmosphere having an oxygen concentration of 15% or higher. Preferably there is.

Moreover, the manufacturing method of the film with a conductive layer may include an insulating layer forming step of forming an insulating layer on the gas barrier layer so as to cover the conductive layer. This insulating layer forming step can be performed, for example, by the same technique as the first insulating layer forming step in the touch panel manufacturing method described above. By forming the insulating layer on the conductive layer by this insulating layer forming step, it is possible to suppress moisture in the atmosphere from reaching the conductive layer, thereby improving the moisture and heat resistance of the film with the conductive layer. be able to.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to the following examples. First, the materials used in the following examples and comparative examples, and the measurements and evaluations performed will be described.

(Acid dianhydride)
In the following examples and comparative examples, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride is used as the acid dianhydride. Product (BPDA), 2,2-bis (4- (3,4-dicarboxyphenoxy) phenyl) propane dianhydride (BSAA), 3,3 ′, 4,4′-diphenyl ether tetracarboxylic dianhydride ( ODPA), 1,2,4,5-benzenetetracarboxylic dianhydride (PMDA), both ends acid anhydride modified methylphenyl silicone oil (X22-168-P5-B) manufactured by Shin-Etsu Chemical Co. Used.

(Diamine compound)
In the following Examples and Comparative Examples, as a diamine compound, trans-1,4-diaminocyclohexane (CHDA), 2,2′-bis (trifluoromethyl) benzidine (TFMB), 2,2-bis [3 -(3-aminobenzamido) -4-hydroxyphenyl] hexafluoropropane (HFHA), bis (3-aminophenyl) sulfone (3,3'-DDS), bis [4- (3-aminophenoxy) phenyl] sulfone (M-BAPS), a both-end amine-modified methylphenyl silicone oil (X22-1660B-3) manufactured by Shin-Etsu Chemical Co., Ltd. is used as necessary.

(solvent)
In the following examples and comparative examples, N-methyl-2-pyrrolidone (NMP), γ-butyrolactone (GBL), propylene glycol monomethyl ether (PGMEA), and dipropylene glycol monomethyl ether (DPM) are used as necessary. Used.

(Alkali-soluble resin)
In the following Examples and Comparative Examples, the alkali-soluble resin AR is used as necessary. The alkali-soluble resin AR is obtained by adding 0.4 equivalent of glycidyl methacrylate to a carboxyl group of a copolymer consisting of methacrylic acid / methyl methacrylate / styrene = 54/23/23 (mol%). is there. The alkali-soluble resin AR has a weight average molecular weight (Mw) of 29,000.

(Conductive particles)
In the following Examples and Comparative Examples, conductive particles A-1 and A-2 are used as necessary as conductive particles. The conductive particles A-1 were silver particles (manufactured by Nisshin Engineering Co., Ltd.) having an average thickness of the surface carbon coating layer of 1 nm and a primary particle diameter of 40 nm. The conductive particles A-2 were silver particles (manufactured by Mitsui Metal Mining Co., Ltd.) having a primary particle size of 0.7 μm.

(First Preparation Example: Preparation of a varnish for forming a polyimide resin film)
In the first production example, a production example of a varnish for forming a polyimide resin film (hereinafter abbreviated as “varnish” as appropriate) used as appropriate in the following Examples and Comparative Examples will be described.

(Synthesis Example 1)
In Synthesis Example 1 of the varnish, ODPA (9.37 g (30.2 mmol)), TFMB (9.67 g (30.2 mmol)), and NMP (100 g) were placed in a 200 mL four-necked flask under a dry nitrogen stream. The mixture was heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain the varnish of Synthesis Example 1. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 1 is 23.5.

(Synthesis Example 2)
In Synthesis Example 2 of the varnish, CBDA (7.23 g (36.9 mmol)), TFMB (11.81 g (36.9 mmol)), and NMP (100 g) were placed in a 200 mL four-necked flask under a dry nitrogen stream. The mixture was heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 2. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 2 is 29.2.

(Synthesis Example 3)
In Synthesis Example 3 of the varnish, ODPA (13.92 g (44.8 mmol)), CHDA (5.12 g (44.8 mmol)), and NMP (100 g) were placed in a 200 mL four-necked flask under a dry nitrogen stream. The mixture was heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 3. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 3 is 35.8.

(Synthesis Example 4)
In Synthesis Example 4 of the varnish, BPDA (11.70 g (39.8 mmol)), BSAA (2.30 g (4.42 mmol)), CHDA (5.04 g ( 44.1 mmol)) and NMP (100 g) were added and heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 4. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 4 is 36.3.

(Synthesis Example 5)
In Synthesis Example 5 of the varnish, CBDA (6.68 g (34.1 mmol)), TFMB (9.27 g (28.9 mmol)), and HFHA (3.09 g (3.09 g 5.11 mmol)) and NMP (100 g) were added and heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 5. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 5 is 27.7.

(Synthesis Example 6)
In Synthesis Example 6 of the varnish, ODPA (8.75 g (28.2 mmol)), TFMB (8.93 g (27.9 mmol)), X22-1660B-3 (in a 200 mL four-necked flask under a dry nitrogen stream) 1.36 g (0.309 mmol)) and NMP (100 g) were added, and the mixture was heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 6. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 6 is 23.4.

(Synthesis Example 7)
In Synthesis Example 7 of the varnish, ODPA (10.58 g (34.1 mmol)), 3,3′-DDS (8.46 g (34.1 mmol)), NMP were added to a 200 mL four-necked flask under a dry nitrogen stream. (100 g) was added and stirred with heating at 60 ° C. This heating and stirring was performed for 8 hours, and then this heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 7. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 7 is 26.8.

(Synthesis Example 8)
In Synthesis Example 8 of varnish, BPDA (13.72 g (46.6 mmol)), CHDA (5.32 g (46.6 mmol)), and NMP (100 g) were placed in a 200 mL four-necked flask under a dry nitrogen stream. The mixture was heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 8. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 8 is 37.7.

(Synthesis Example 9)
In Synthesis Example 9 of the varnish, ODPA (7.95 g (25.6 mmol)), m-BAPS (11.09 g (25.6 mmol)), and NMP (100 g) were placed in a 200 mL four-necked flask under a dry nitrogen stream. And heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then the heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 9. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 9 is 19.8.

(Synthesis Example 10)
In Synthesis Example 10 of the varnish, ODPA (3.97 g (12.8 mmol)), PMDA (2.79 g (12.8 mmol)), TFMB (8.11 g (8.11 g 25.3 mmol)), X22-1660B-3 (1.18 g (0.282 mmol)) and NMP (100 g) were added, and the mixture was heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then this heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 10. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 10 is 25.4.

(Synthesis Example 11)
In Synthesis Example 11 of the varnish, ODPA (7.85 g (25.3 mmol)) and X22-168-P5-B (1.18 g (0.282 mmol)) were placed in a 200 mL four-necked flask under a dry nitrogen stream. TFMB (8.20 g (25.6 mmol)) and NMP (100 g) were added and heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then this heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 11. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 11 is 23.4.

(Synthesis Example 12)
In Synthesis Example 12 of the varnish, ODPA (3.97 g (12.8 mmol)), BPDA (3.77 g (12.8 mmol)), and TFMB (8.11 g (8.11 g 25.3 mmol)), X22-1660B-3 (1.18 g (0.282 mmol)) and NMP (100 g) were added, and the mixture was heated and stirred at 60 ° C. This heating and stirring was performed for 8 hours, and then this heating and stirring was cooled to room temperature to obtain a varnish of Synthesis Example 12. The imide group density | concentration of the polyimide which can be produced using the varnish of this synthesis example 12 is 23.3.

(Second Preparation Example: Preparation of Conductive Composition)
In the second production example, preparation of conductive compositions AE-1 and AE-2 that are appropriately used in the following Examples and Comparative Examples will be described. In this second production example, conductive particles A-1 (80 g), a surfactant “DISPERBYK” (registered trademark) 21116 (4.06 g) manufactured by DIC, PGMEA (98.07 g), DPM ( 98.07 g) were mixed, and the mixture was treated with a homogenizer at 1200 rpm for 30 minutes. Furthermore, this processed mixture was dispersed using a high-pressure wet medialess atomizer Nanomizer (manufactured by Nanomizer) to obtain a silver dispersion L1 having a silver content of 40% by mass. Further, a silver dispersion L2 was obtained in the same manner as above except that the conductive particles A-2 were used instead of the conductive particles A-1.

Next, alkali-soluble resin AR (20 g) as an organic compound, ALCH (0.6 g) as a metal chelate compound, NCI-831 (2.4 g) as a photopolymerization initiator, and PE-3A (12.0 g) PGMEA (132.6 g) and DPM (52.6 g) were added to the mixture and stirred. Thereby, the organic liquid L3 for conductive compositions was obtained. ALCH is a metal chelate compound (ethyl acetoacetate aluminum diisopropylate) manufactured by Kawaken Fine Chemicals. NCI-831 is a photopolymerization initiator manufactured by ADEKA. Thereafter, the silver dispersions L1 and L2 and the organic liquid L3 obtained as described above were mixed in the ratios shown in Table 1, respectively, thereby obtaining conductive compositions AE-1 and AE-2.

(Third Preparation Example: Preparation of Insulating Composition)
In the third production example, preparation of insulating compositions OA-1 and OA-2 used as appropriate in the following examples and comparative examples will be described. In this third production example, V-259ME (50.0 g) manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd. as a cardo resin having two or more structures represented by the structural formula (10) described above in a clean bottle and crosslinkability were used. TAIC (18.0 g) manufactured by Nippon Kasei Co., Ltd. as a monomer, M-315 (10.0 g) manufactured by Toagosei Co., Ltd. as a crosslinkable monomer, and PG-100 (20.0 g) manufactured by Osaka Gas Chemical Co., Ltd. as an epoxy compound. ) And OXE-01 (0.2 g) manufactured by BASF as a photopolymerization initiator were mixed, and the mixture was stirred for 1 hour. Thereby, an insulating composition OA-1 was obtained. In addition, an insulating composition OA-2 was obtained in the same manner as above except that the alkali-soluble resin AR was used in place of the cardo resin (V-259ME).

(Fourth preparation example: Preparation of polyimide resin film)
In the fourth production example, production of a polyimide resin film T1 used as appropriate in the following examples and comparative examples will be described. In this fourth fabrication example, a film thickness after pre-baking for 4 minutes at a temperature of 140 ° C. is applied to a 6-inch mirror silicon wafer as a substrate using a coating and developing apparatus (Mark-7) manufactured by Tokyo Electron. The varnish of the first production example (any of the varnishes of Synthesis Examples 1 to 12) was spin-coated so as to be ± 0.5 μm. Thereafter, this varnish coating film was pre-baked for 4 minutes at a temperature of 140 ° C. using a Mark-7 hot plate. Using the inert oven (INH-21CD) manufactured by Koyo Thermo Systems Co., Ltd., the prebaked film thus obtained was heated to 350 ° C. at a temperature increase rate of 3.5 ° C./min under a nitrogen stream (oxygen concentration of 20 ppm or less). The temperature was raised and held for 30 minutes. Thereafter, the pre-baked film was cooled to 50 ° C. at a rate of temperature decrease of 5 ° C./min, thereby producing a polyimide resin film T1. Subsequently, the polyimide resin film T1 (attached to the substrate) is immersed in hydrofluoric acid for 1 to 4 minutes, the polyimide resin film T1 is peeled off from the substrate, and air-dried to obtain a polyimide resin film T1 (single unit). Got.

(Fifth preparation example: Preparation of polyimide resin film with glass substrate)
In the fifth fabrication example, fabrication of a polyimide resin film T2 used as appropriate in the following examples and comparative examples will be described. In this fifth manufacturing example, a spin coater (MS-A200) manufactured by Mikasa was used for 4 minutes at a temperature of 140 ° C. on a glass substrate (Tempax) having a length of 50 mm × width 50 mm × thickness 1.1 mm. The varnish of the first production example (any of the varnishes of Synthesis Examples 1 to 12) was spin-coated so that the film thickness after pre-baking was 15 ± 0.5 μm. Thereafter, the varnish coating film was pre-baked for 4 minutes at a temperature of 140 ° C. using a hot plate (D-SPIN) manufactured by Dainippon Screen. Using the inert oven (INH-21CD) manufactured by Koyo Thermo Systems Co., Ltd., the prebaked film thus obtained was heated to 350 ° C. at a temperature increase rate of 3.5 ° C./min under a nitrogen stream (oxygen concentration of 20 ppm or less). The temperature was raised and held for 30 minutes. Thereafter, the pre-baked film was cooled to 50 ° C. at a temperature lowering rate of 5 ° C./min, thereby producing a polyimide resin film T2 attached to a rectangular glass substrate.

(Sixth preparation example: Preparation of polyimide resin film with glass substrate)
In the sixth production example, production of a polyimide resin film T3 that is appropriately used in the following examples and comparative examples will be described. In this sixth production example, pre-baking for 4 minutes at a temperature of 140 ° C. using a spin coater (1H-360S) manufactured by Mikasa on a glass substrate having an outer diameter of 13 inches (AN-100 manufactured by Asahi Glass Co., Ltd.). The varnish of the first fabrication example (any varnish of Synthesis Examples 1 to 12) was spin-coated so that the subsequent film thickness was 15 ± 0.5 μm. Thereafter, the varnish coating film was pre-baked at a temperature of 140 ° C. for 4 minutes using a hot plate. Using the inert oven (INH-21CD) manufactured by Koyo Thermo Systems Co., Ltd., the prebaked film thus obtained was heated to 350 ° C. at a temperature increase rate of 3.5 ° C./min under a nitrogen stream (oxygen concentration of 20 ppm or less). The temperature was raised and held for 30 minutes. Thereafter, the pre-baked film was cooled to 50 ° C. at a temperature lowering rate of 5 ° C./min. Thereby, a polyimide resin film T3 adhered to a circular glass substrate was produced.

(Seventh preparation example: Preparation of polyimide resin film with silicon substrate)
In the seventh production example, production of a polyimide resin film T4 used as appropriate in the following examples and comparative examples will be described. In this sixth manufacturing example, a film thickness after pre-baking for 4 minutes at a temperature of 140 ° C. using a spin coater (MS-A200) manufactured by Mikasa on a 4-inch silicon substrate cut into ¼ is 5 The varnish of the first production example (any of the varnishes of Synthesis Examples 1 to 12) was spin-coated so as to be ± 0.5 μm. Thereafter, the varnish coating film was pre-baked for 4 minutes at a temperature of 140 ° C. using a hot plate (D-SPIN) manufactured by Dainippon Screen. Using the inert oven (INH-21CD) manufactured by Koyo Thermo Systems Co., Ltd., the prebaked film thus obtained was heated to 300 ° C. at a temperature rising rate of 3.5 ° C./min under a nitrogen stream (oxygen concentration of 20 ppm or less). The temperature was raised and held for 30 minutes. Thereafter, this pre-baked film was cooled to 50 ° C. at a temperature lowering rate of 5 ° C./min, and thereby a polyimide resin film T4 adhered to the silicon substrate was produced.

(First measurement example: measurement of light transmittance (T))
In the first measurement example, the measurement of light transmittance used as appropriate in the following examples and comparative examples will be described. In this first measurement example, the light transmittance at a wavelength of 450 nm of the polyimide resin film T2 of the fifth preparation example was measured using an ultraviolet-visible spectrophotometer (MultiSpec 1500) manufactured by Shimadzu Corporation.

(Second measurement example: measurement of haze value)
In the second measurement example, measurement of a haze value used as appropriate in the following examples and comparative examples will be described. In this second measurement example, the haze value (%) of the polyimide resin film T2 of the fifth production example was measured using a direct reading haze computer (HGM2DP, C light source) manufactured by Suga Test Instruments Co., Ltd. In addition, as this haze value, the average value of 3 times measurement was used.

(Third measurement example: measurement of glass transition temperature (Tg) and linear expansion coefficient (CTE))
In the third measurement example, measurement of the glass transition temperature and the linear expansion coefficient used as appropriate in the following examples and comparative examples will be described. In this third measurement example, the glass transition temperature and the linear expansion coefficient of the polyimide resin film T1 of the fourth production example are measured under a nitrogen stream using a thermomechanical analyzer (EXSTAR6000TMA / SS6000) manufactured by SII Nanotechnology. Measured in compressed mode. About the sample for this measurement, a piece of 15 mm width × 30 mm length was cut out from the polyimide resin film T1, and this piece was wound in the longitudinal direction and passed through a platinum coil having a diameter of 3 mm and a height of 15 mm to form a cylindrical shape. Using. The temperature raising method was performed under the following conditions. In the first stage, the sample was heated to 150 degrees at a temperature increase rate of 5 ° C./min to remove the adsorbed water from the sample. In the second stage, the sample was air-cooled to room temperature at a rate of 5 ° C./min. In the third stage, the sample was measured at a rate of temperature increase of 5 ° C./min to determine the glass transition temperature of the polyimide resin film T1. In the third stage, the average value of the linear expansion coefficients of the samples at 50 to 200 ° C. was obtained and used as the linear expansion coefficient of the polyimide resin film T1.

(Fourth measurement example: measurement of residual stress)
In the fourth measurement example, measurement of residual stress used as appropriate in the following examples and comparative examples will be described. In this fourth measurement example, a radius of curvature r ₁ of a 6-inch silicon wafer having a thickness of 625 μm ± 25 μm was measured in advance using a residual stress measuring device (FLX-3300-T) manufactured by Toago Technology Co., Ltd. . On the silicon wafer, using a coating and developing apparatus (Mark-7) manufactured by Tokyo Electron Co., Ltd., the film thickness after pre-baking for 4 minutes at a temperature of 140 ° C. is 15 ± 0.5 μm. The varnish of the manufacturing example (any varnish of Synthesis Examples 1 to 12) was spin-coated. Thereafter, this varnish coating film was pre-baked for 4 minutes at a temperature of 140 ° C. using a Mark-7 hot plate. Using the inert oven (INH-21CD) manufactured by Koyo Thermo Systems Co., Ltd., the prebaked film thus obtained was heated to 350 ° C. at a temperature increase rate of 3.5 ° C./min under a nitrogen stream (oxygen concentration of 20 ppm or less). The temperature was raised and held for 30 minutes. Thereafter, the pre-baked film was cooled to 50 ° C. at a temperature decrease rate of 5 ° C./min, thereby producing a silicon wafer with a polyimide resin film. After the silicon wafer was dried at 150 ° C. for 10 minutes, the curvature radius r ₂ of the silicon wafer was measured using the above-described residual stress measuring apparatus. And the residual stress σ (Pa) generated between the silicon wafer and the polyimide resin film according to the following formula (II)
Asked.

^{_{σ = Eh 2/6 [(}} 1 / r 2) - (1 / r 1)] t (II)

In the formula (II), E is the biaxial elastic modulus (Pa) of the silicon wafer. h is the thickness (m) of the silicon wafer. t is the film thickness (m) of the polyimide resin film. r ₁ is a curvature radius (m) of the silicon wafer before the polyimide resin film is produced. r ₂ is the radius of curvature (m) of the silicon wafer after the polyimide resin film is produced. The biaxial elastic modulus E of the silicon wafer was determined as 1.805 × 10 ⁻¹¹ (Pa).

(Evaluation Examples 1 to 12)
In Evaluation Examples 1 to 12, polyimide resin films T1 to T4 were produced for the varnishes of Synthesis Examples 1 to 12 described above by the methods of the fourth production example to the seventh production example, and the first measurement example to the fourth measurement example. The light transmittance, haze value, glass transition temperature (Tg), linear expansion coefficient, and residual stress were measured by the above method. The results of Evaluation Examples 1 to 12 are shown in Table 2.

Next, touch panel evaluation methods performed in the following examples and comparative examples will be described.

(Conductivity evaluation)
In the conductivity evaluation of the touch panel, in each example and each comparative example, a surface resistance measuring machine (“Loresta” (registered trademark) -FP, manufactured by Mitsubishi Yuka Co., Ltd.) was used for the substrate fabricated up to the first wiring layer of the touch panel. Is used to measure the surface resistance value ρs (Ω / □), and the thickness t (cm) of the wiring portion is measured using a surface roughness shape measuring instrument ("Surfcom" (registered trademark) 1400D, manufactured by Tokyo Seimitsu Co., Ltd.). The volume resistivity (μΩ · cm) was calculated by multiplying the values. Using the obtained volume resistivity, the conductivity of the touch panel was evaluated according to the following evaluation criteria. In this evaluation, the case where the evaluation result was level 2 or higher was regarded as acceptable.

When the volume resistivity is less than 60 μΩ · cm in the evaluation criteria of conductivity evaluation, it is level 5. When the volume resistivity is 60 μΩ · cm or more and less than 80 μΩ · cm, it is Level 4. When the volume resistivity is 80 μΩ · cm or more and less than 100 μΩ · cm, it is Level 3. Level 2 when the volume resistivity is 100 μΩ · cm or more and less than 150 μΩ · cm. Level 1 when the volume resistivity is 150 μΩ · cm or more.

(Evaluation of residue of conductive composition)
In the residue evaluation of the conductive composition of the touch panel, in each example and each comparative example, the transmittance at a wavelength of 400 nm before and after the formation of the first wiring layer in the unexposed portion of the substrate manufactured up to the first wiring layer of the touch panel. Was measured using an ultraviolet-visible spectrophotometer (“MultiSpec-1500 (trade name)” manufactured by Shimadzu Corporation). Then, when the transmittance before forming the first wiring layer is T0 and the transmittance after forming the first wiring layer is T, the transmittance change represented by the formula (T0-T) / T0 is calculated. did. Using the obtained value of transmittance change, the residue of the conductive composition of the touch panel was evaluated according to the following evaluation criteria. In this evaluation, the case where the evaluation result was level 2 or higher was regarded as acceptable.

In the evaluation criteria for evaluating the residue of the conductive composition, when the value of transmittance change is less than 1%, it is level 5. When the value of the transmittance change is 1% or more and less than 2%, it is level 4. When the value of the transmittance change is 2% or more and less than 3%, it is level 3. When the transmittance change value is 3% or more and less than 4%, it is level 2. When the value of the transmittance change is 4% or more, it is level 1.

(Evaluation of color (b *))
In the color (b *) evaluation of the touch panel, the color of the laminated substrate was evaluated by the following method using the substrate prepared up to the second insulating layer of the touch panel in each example and each comparative example.

Using a spectrophotometer (CM-2600d, manufactured by Konica Minolta Co., Ltd.), the reflectance of the total reflected light is measured from the glass substrate side of the substrate manufactured up to the second insulating layer of the touch panel, and CIE (L *, a *, B *) The color characteristic b * was measured in the color space. Using the obtained color characteristic b *, the color of the touch panel was evaluated according to the following evaluation criteria. In this evaluation, the case where the evaluation result was level 2 or higher was regarded as acceptable. A D65 light source was used as the light source.

If the color characteristic b * is −2 ≦ b * ≦ 2 in the evaluation criteria of the color eye evaluation, it is level 5. Level 4 when the color characteristic b * is −3 ≦ b * <− 2 or 2 <b * ≦ 3. If the color characteristic b * is −4 ≦ b * <− 3 or 3 <b * ≦ 4, it is level 3. If the color characteristic b * is −5 ≦ b * <− 4 or 4 <b * ≦ 5, it is level 2. If the color characteristic b * is b * <− 5 or 5 <b *, it is level 1.

(Moisture and heat resistance evaluation)
In the wet heat resistance evaluation of the touch panel, the wet heat resistance was evaluated by the following method for the touch panels produced in each of the examples and the comparative examples.

For measurement of wet heat resistance, an insulation deterioration characteristic evaluation system “ETAC SIR13” (manufactured by Enomoto Kasei Co., Ltd.) was used. An electrode was attached to each end of the first wiring layer and the second wiring layer of the touch panel, and the touch panel was placed in a high-temperature and high-humidity tank set at 85 ° C. and 85% RH. After 5 minutes from the stabilization of the environment in the tank, a voltage was applied between the electrodes of the first wiring layer and the second wiring layer, and the change in insulation resistance with time was measured. With the first wiring layer as the positive electrode and the second wiring layer as the negative electrode, a voltage of 10 V was applied, and the resistance value for 500 hours was measured at 5-minute intervals. When the measured resistance value reached 10 5 or less, it was judged as a short circuit due to poor insulation, the printing pressure was stopped, and the test time up to that time was defined as the short circuit time. Using the obtained short circuit time, the wet heat resistance of the touch panel was evaluated according to the following evaluation criteria. In this evaluation, the case where the evaluation result was level 2 or higher was regarded as acceptable.

When the short-circuit time is 1000 hours or more in the evaluation criteria of the wet heat resistance evaluation, it is level 5. When the short circuit time is 500 hours or more and less than 1000 hours, it is level 4. When the short circuit time is 300 hours or more and less than 500 hours, it is level 3. When the short circuit time is 100 hours or more and less than 300 hours, it is level 2. If the short circuit time is less than 100 hours, it is level 1.

(Dimensional accuracy evaluation)
In the dimensional accuracy evaluation of the touch panel, the dimensional accuracy was evaluated by the following method for the touch panels produced in each Example and each Comparative Example.

The horizontal shift was measured at the design portion where the mesh intersection of the first wiring layer and the mesh intersection of the second wiring layer overlapped at the center of the multilayer substrate. Using the obtained measurement value of “deviation”, the dimensional accuracy of the touch panel was evaluated according to the following evaluation criteria. In this evaluation, the case where the evaluation result was level 2 or higher was regarded as acceptable.

If the deviation is less than 1 μm in the dimensional accuracy evaluation criteria, it is level 5. When the deviation is 1 μm or more and less than 2 μm, it is level 4. When the deviation is 2 μm or more and less than 3 μm, it is level 3. When the deviation is 3 μm or more and less than 5 μm, it is level 2. When the deviation is 5 μm or more, it is level 1.

(ESD (electrostatic discharge) resistance evaluation)
In the ESD resistance evaluation of the touch panel, the ESD test apparatus (Compact ESD Simulator HCE-5000, manufactured by Hanwa Denshi Kogyo Co., Ltd.) is used for the substrate manufactured up to the first wiring layer of the touch panel in each example and each comparative example. Resistance was evaluated. Specifically, an electrode was attached to the end of the first wiring layer, and the voltage was continuously applied once in 100V steps starting from 100V. When the resistance value of the leakage current after voltage application is increased by 10% or more compared to before the voltage application, it is considered that the wiring layer is disconnected, and a voltage that is 100V lower than the disconnected voltage is defined as the ESD withstand voltage. did.

Example 1
<Formation of polyimide resin film>
In Example 1, the polyimide resin film T3 was produced by the method of the sixth production example using the varnish of Synthesis Example 1 produced in the first production example.

<Formation of gas barrier layer>
In Example 1, on the polyimide resin film T3 obtained as described above, by using a target made of SiO _2, performs sputtering in an argon atmosphere, forming a gas barrier layer made of SiO ₂ having a thickness of 100nm did. As sputtering conditions at this time, the pressure was 2 × 10 ⁻¹ Pa, the substrate temperature was 150 ° C., and the power source was an AC power source of 13.56 MHz.

<Formation of first wiring layer>
In Example 1, the conductive composition AE-1 produced in the second production example was placed on a spin coater (“1H-360S (trade name) manufactured by Mikasa Co., Ltd.) on the substrate on which the polyimide resin film T3 and the gas barrier layer were formed. ) "), And spin-coated under the conditions of 300 rpm for 10 seconds and 500 rpm for 2 seconds. Thereafter, the coating film of the conductive composition AE-1 was prebaked at 100 ° C. for 2 minutes using a hot plate (“SCW-636 (trade name)” manufactured by Dainippon Screen Mfg. Co., Ltd.) to prepare a prebaked film. . Subsequently, this pre-baked film was exposed through a desired mask using a parallel light mask aligner (“PLA-501F (trade name)” manufactured by Canon Inc.) using an ultrahigh pressure mercury lamp as a light source. Thereafter, the pre-baked film was subjected to shower development with a 0.045 mass% aqueous potassium hydroxide solution for 60 seconds using an automatic developing device (“AD-2000 (trade name)” manufactured by Takizawa Sangyo Co., Ltd.), and then with water. The pattern was processed by rinsing for 30 seconds. The substrate thus patterned was cured in the air (oxygen concentration 21%) at 250 ° C. for 30 minutes using an oven to form a first wiring layer.

<Formation of first insulating layer>
In Example 1, the insulating composition OA-1 produced in the third production example was spin-coated at 650 rpm for 5 seconds on the substrate on which the first wiring layer was formed, using a spin coater. Thereafter, the coating film of this insulating composition OA-1 was pre-baked at 100 ° C. for 2 minutes using a hot plate to prepare a pre-baked film. Next, this pre-baked film was exposed through a desired mask using a parallel light mask aligner using an ultrahigh pressure mercury lamp as a light source. Thereafter, the prebaked film was subjected to shower development with a 0.045 mass% potassium hydroxide aqueous solution for 60 seconds using an automatic developing device, and then rinsed with water for 30 seconds to perform pattern processing. The substrate thus patterned was cured in an air (oxygen concentration: 21%) at 250 ° C. for 60 minutes to form a first insulating layer.

<Formation of second wiring layer>
In Example 1, the second wiring layer was formed on the substrate on which the first insulating layer was formed as described above by the same method as the first wiring layer.

<Formation of second insulating layer>
In Example 1, the second insulating layer was formed on the substrate on which the second wiring layer was formed as described above by the same method as the first insulating layer.

Finally, the periphery of the area where the first wiring layer and the second wiring layer were formed was cut with a single blade from the upper surface, and mechanically peeled from the cut end surface to obtain the touch panel of Example 1. About the obtained touch panel of Example 1, the conductivity, the residue of the conductive composition, the color (b *), the moist heat resistance, the dimensional accuracy, and the ESD voltage resistance were evaluated by the methods described above. The evaluation results of Example 1 are shown in Table 3 described later.

(Example 2)
In Example 2, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 2 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 2, since the polyimide contained in the polyimide resin film has the structural unit of the general formula (1), the dimensional accuracy is improved and the level of the evaluation result is “5”. It became. The color was slightly deteriorated due to yellowing during wiring processing, and the evaluation result level was “3”.

(Example 3)
In Example 3, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 3 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 3, since the polyimide contained in the polyimide resin film has the structural unit of the general formula (2), the dimensional accuracy is improved and the level of the evaluation result is “4”. It became. The color was slightly deteriorated due to yellowing during wiring processing, and the evaluation result level was “3”.

Example 4
In Example 4, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 4 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 4, since the polyimide contained in the polyimide resin film has the structural unit of the general formula (2), the dimensional accuracy is improved and the evaluation result level is “5”. It became. The color was slightly deteriorated due to yellowing during wiring processing, and the evaluation result level was “3”.

(Example 5)
In Example 5, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 5 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 5, the polyimide contained in the polyimide resin film has a structural unit represented by the general formula (4) as a main component and a structure represented by the general formula (5). Since the unit contained 5 mol% or more and 30 mol% or less of all the structural units, the dimensional accuracy was improved and the evaluation result level was “5”.

(Example 6)
In Example 6, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 6 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 6, since the polyimide included in the polyimide resin film has a repeating structure represented by the general formula (9), the dimensional accuracy is improved and the level of the evaluation result is “5”. Moreover, ESD withstand voltage improved and became 1200V.

(Example 7)
In Example 7, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 7 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 7, since the Tg of the polyimide resin film is slightly low (see Evaluation Example 7 in Table 2), the dimensional accuracy deteriorates and the evaluation result level is “2”. However, it was in a usable range.

(Example 8)
In Example 8, the same operation as Example 1 was repeated except that the varnish of Synthesis Example 10 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 8, since the polyimide contained in the polyimide resin film has a repeating structure represented by the general formula (9), the dimensional accuracy is improved and the level of the evaluation result is “5”. Moreover, ESD withstand voltage improved and became 1200V.

Example 9
In Example 9, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 11 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 9, since the polyimide contained in the polyimide resin film has a repeating structure represented by the general formula (9), the dimensional accuracy is improved and the level of the evaluation result is “5”. Moreover, ESD withstand voltage improved and became 1200V.

(Example 10)
In Example 10, the same operation as in Example 1 was repeated except that the varnish of Synthesis Example 12 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 10, since the polyimide contained in the polyimide resin film has a repeating structure represented by the general formula (9), the dimensional accuracy is improved and the level of the evaluation result is “5”. Moreover, ESD withstand voltage improved and became 1100V.

(Example 11)
In Example 11, the same operation as Example 5 was repeated except that the target was changed to a target made of SiON when forming the gas barrier layer. As shown in Table 3, in the touch panel of Example 11, by changing the gas barrier layer, the color was improved and the evaluation result level was “5”. On the other hand, chemical resistance decreased by changing the gas barrier layer. As a result, the conductive composition residue and the dimensional accuracy slightly deteriorated, and the evaluation result level was “4”, but both were in the usable range.

(Example 12)
In Example 12, when forming the gas barrier layer, first, sputtering was performed in an argon atmosphere using a target made of SiON to form a gas barrier layer made of SiON having a thickness of 80 nm. Next, using a target of SiO _2, performs sputtering in an argon atmosphere to form a gas barrier layer made of SiO ₂ having a thickness of 20 nm. Except this, the same operation as in Example 5 was repeated. As shown in Table 3, in the touch panel of Example 12, by setting the gas barrier layer on the polyimide resin film side to SiON, yellowing during wiring processing is suppressed, and as a result, the color is improved and the evaluation result The level is now “5”. Further, since the barrier property of the gas barrier layer was improved, the heat and humidity resistance was improved, and the evaluation result level was “5”. Furthermore, since the gas barrier layer on the wiring layer side was made of SiO ₂ , the conductive composition residue and dimensional accuracy were good, with the evaluation result level remaining at “5”.

(Example 13)
In Example 13, the same operation as in Example 5 was repeated except that the conductive composition was changed from the conductive composition AE-1 to the conductive composition AE-2. As shown in Table 3, in the touch panel of Example 13, the conductive particles (metal fine particles) contained in the conductive composition AE-2 were not coated, and the metal fine particles aggregated non-uniformly in the wiring layer. did. Therefore, although the conductivity deteriorated and the evaluation result level was “3”, it was in a usable range. Moreover, although the conductive composition residue and the dimensional accuracy were slightly deteriorated and the level of the evaluation result was “4”, it was in a range where there was no problem in use.

(Example 14)
In Example 14, the same operation as in Example 5 was repeated except that the insulating composition was changed from the insulating composition OA-1 to the insulating composition OA-2. As shown in Table 3, in the touch panel of Example 14, since the insulating layer does not have a predetermined cardo resin, the heat and humidity resistance is greatly deteriorated and the evaluation result level is “2”. It was possible. The conductivity, the conductive composition residue, and the dimensional accuracy were slightly deteriorated and the evaluation result level was “4”.

(Example 15)
In Example 15, when the wiring layer was formed, the patterned substrate was heated using an inert oven (INH-21CD manufactured by Koyo Thermo Systems Co., Ltd.) under a nitrogen stream (oxygen concentration 14%). The same operation as in Example 5 was repeated. As shown in Table 3, in the touch panel of Example 15, due to the change in the oxygen concentration during the formation of the wiring layer, the color was improved and the evaluation result level was “5”. On the other hand, the conductivity was greatly deteriorated and the evaluation result level was “2”, but it was in a usable range. The dimensional accuracy slightly deteriorated and the evaluation result level was “4”, but it was in a range where there was no problem in use.

(Example 16)
In Example 16, the same operation as in Example 11 was repeated except that the varnish of Synthesis Example 6 was used as the polyimide resin film-forming varnish. As shown in Table 3, in the touch panel of Example 16, since the polyimide contained in the polyimide resin film has a repeating structure represented by the general formula (9), the dimensional accuracy is improved and the level of the evaluation result is “5”. Moreover, ESD withstand voltage improved and became 1300V.

(Example 17)
In Example 17, the same operation as in Example 12 was repeated except that the varnish of Synthesis Example 6 was used as the varnish for forming a polyimide resin film. As shown in Table 3, in the touch panel of Example 17, since the polyimide contained in the polyimide resin film has a repeating structure represented by the general formula (9), the ESD withstand voltage is improved to 1300 V. .

(Comparative Example 1)
In Comparative Example 1, the same operation as in Example 5 was repeated except that the first wiring layer was formed directly on the polyimide resin film without forming the gas barrier layer. In the touch panel of Comparative Example 1, the conductive composition residue, color, and heat-and-moisture resistance were significantly lowered, and the level was unusable (level 1).

(Comparative Example 2)
In Comparative Example 2, the same operation as in Example 5 was repeated except that the varnish of Synthesis Example 8 was used as the varnish for forming a polyimide resin film. In the touch panel of Comparative Example 2, the imide group concentration of the polyimide contained in the polyimide resin film was high, and haze was generated after the resin film was formed, and the visibility was greatly impaired. For this reason, the polyimide resin film in Comparative Example 2 was not applicable as a touch panel substrate.

(Comparative Example 3)
In Comparative Example 3, the same operation as in Example 5 was repeated except that the varnish of Synthesis Example 9 was used as the polyimide resin film-forming varnish. In the touch panel of Comparative Example 2, since the imide group concentration of the polyimide contained in the polyimide resin film is low and the Tg of the polyimide resin film is reduced (see Evaluation Example 9 in Table 2), the dimensional accuracy is greatly reduced and cannot be used. Level (level 1). The evaluation results of Comparative Examples 1 to 3 are shown in Table 3 together with the evaluation results of Examples 1 to 17 described above.

As described above, the method for manufacturing a film with a conductive layer, a touch panel, a film with a conductive layer, and a method for manufacturing a touch panel according to the present invention suppresses yellowing of the resin film during formation of the conductive layer and provides high dimensional accuracy of the conductive layer. Is suitable for a film with a conductive layer, a touch panel, a method for producing a film with a conductive layer, and a method for producing a touch panel.

DESCRIPTION OF SYMBOLS 1 Resin film 2 Gas barrier layer 3 1st wiring layer 3A Conductive layer 4 1st insulating layer 5 2nd wiring layer 6 2nd insulating layer 7 Support substrate 8 Cut end surface 10 Touch panel 11 Film with a conductive layer

Claims

A film with a conductive layer having a conductive layer containing conductive particles on a resin film containing polyimide having an imide group concentration defined by the following formula (I) of 20.0% or more and 36.5% or less, ,
Having a gas barrier layer between the resin film and the conductive layer;
A film with a conductive layer characterized by the above.
(Molecular weight of imide group part) / (Molecular weight of repeating unit of polyimide) × 100 [%] (I)
The glass transition temperature of the resin film is 250 ° C. or higher.
The film with a conductive layer according to claim 1.
The polyimide includes a structural unit represented by the following general formula (1).
The film with a conductive layer according to claim 1 or 2.

(In General Formula (1), R 1 has a monocyclic or condensed polycyclic alicyclic structure, a tetravalent organic group having 4 to 40 carbon atoms, or a monocyclic alicyclic structure. A tetravalent organic group having 4 to 40 carbon atoms in which the organic groups are connected to each other directly or via a crosslinked structure, R 2 represents a divalent organic group having 4 to 40 carbon atoms.
The polyimide includes a structural unit represented by the following general formula (2).
The film with a conductive layer according to any one of claims 1 to 3, wherein the film has a conductive layer.

(In General Formula (2), R 3 represents a tetravalent organic group having 4 to 40 carbon atoms. R 4 has a monocyclic or condensed polycyclic alicyclic structure and has 4 to 40 carbon atoms. Or a divalent organic group having 4 to 40 carbon atoms in which organic groups having a monocyclic alicyclic structure are connected to each other directly or via a crosslinked structure, or the following general group A divalent organic group represented by the formula (3) is shown.)

(In General Formula (3), X 1 is a divalent hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a halogen atom. Ar 1 and Ar 2 are each independently a carbon number. Represents a divalent aromatic group of 4 to 40.)
The polyimide includes a structural unit represented by the following general formula (4) as a main component, and includes a structural unit represented by the following general formula (5) in a range of 5 mol% to 30 mol% of all structural units.
The film with a conductive layer according to any one of claims 1 to 4, wherein the film has a conductive layer.

(In the general formulas (4) and (5), R 1 represents a monovalent or condensed polycyclic alicyclic structure, a tetravalent organic group having 4 to 40 carbon atoms, or a monocyclic fatty acid. A tetravalent organic group having 4 to 40 carbon atoms in which organic groups having a ring structure are connected to each other directly or via a crosslinked structure, R 13 is a divalent group represented by the following general formula (6). R 14 is a structure represented by the following structural formula (7) or the following structural formula (8).

(In the general formula (6), R 15 to R 22 each independently represent a hydrogen atom, a halogen atom, or a monovalent organic group having 1 to 3 carbon atoms which may be substituted with a halogen atom. X 2 is selected from a direct bond, an oxygen atom, a sulfur atom, a sulfonyl group, a divalent organic group having 1 to 3 carbon atoms which may be substituted with a halogen atom, an ester bond, an amide bond, and a sulfide bond. Structure.)
The polyimide contains a repeating structure represented by the following general formula (9) in at least one of an acid dianhydride residue and a diamine residue constituting the polyimide.
The film with a conductive layer according to claim 1, wherein the film has a conductive layer.

(In the general formula (9), R 23 and R 24 each independently represents a monovalent organic group having 1 to 20 carbon atoms. M is an integer of 3 to 200.)
The polyimide includes a triamine skeleton,
The film with a conductive layer according to any one of claims 1 to 6, wherein the film has a conductive layer.
The gas barrier layer includes at least one of silicon oxide, silicon nitride, silicon oxynitride, and silicon carbonitride.
The film with a conductive layer according to any one of claims 1 to 7, wherein the film has a conductive layer.
The gas barrier layer includes a component represented by SiOxNy (x and y are values satisfying 0 <x ≦ 1, 0.55 ≦ y ≦ 1 and 0 ≦ x / y ≦ 1).
9. The film with a conductive layer according to claim 1, wherein the film has a conductive layer.
The gas barrier layer is an inorganic film laminated in two or more layers,
Of the inorganic film, a layer in contact with the conductive layer is formed of a component represented by SiOz (z is a value satisfying 0.5 ≦ z ≦ 2).
10. The film with a conductive layer according to claim 1, wherein the film has a conductive layer.
The conductive particles are silver particles.
The film with a conductive layer according to any one of claims 1 to 10, wherein the film has a conductive layer.
On the conductive layer, an insulating layer formed of an alkali-soluble resin containing a cardo resin having two or more structures represented by the following structural formula (10) is provided.
The film with a conductive layer according to any one of claims 1 to 11, wherein the film has a conductive layer.
A film with a conductive layer according to any one of claims 1 to 12,
The conductive layer is a wiring layer;
A touch panel characterized by that.
A resin film forming step of forming a resin film containing polyimide on the support substrate;
A gas barrier layer forming step of forming a gas barrier layer on the resin film;
A conductive layer forming step of forming a conductive layer on the gas barrier layer;
A peeling step of peeling the resin film from the support substrate;
A method for producing a film with a conductive layer, comprising:
The conductive layer forming step forms the conductive layer using a conductive composition containing conductive particles having a coating layer on at least a part of the surface.
The manufacturing method of the film with a conductive layer of Claim 14 characterized by the above-mentioned.
In the resin film forming step, the polyimide resin composition on the support substrate is heated at a temperature of 300 ° C. or more and 500 ° C. or less in an atmosphere having an oxygen concentration of 1000 ppm or less to form the resin film,
In the conductive layer forming step, the conductive composition on the gas barrier layer is heated at a temperature of 100 ° C. or higher and 300 ° C. or lower in an atmosphere having an oxygen concentration of 15% or higher to form the conductive layer.
The manufacturing method of the film with a conductive layer of Claim 14 or 15 characterized by the above-mentioned.
A method for producing a touch panel using the method for producing a film with a conductive layer according to any one of claims 14 to 16,
The conductive layer forming step is a step of forming a wiring layer as the conductive layer.
A manufacturing method of a touch panel characterized by the above.