FIELD

The present invention relates to an electroconductive film.

BACKGROUND

As a transparent electroconductive member, there is known an electroconductive glass having an indium oxide thin film formed on a glass plate. However, the electroconductive glass uses glass as a substrate and thus has poor flexibility and processability, which makes it difficult to use the electroconductive glass in some applications. To address this issue, an electroconductive film utilizing a resin has been proposed as a transparent electroconductive member having excellent flexibility and processability (See Patent Literatures 1 and 2).

Further, a technology as disclosed in Patent Literature 3 has been known.

CITATION LIST

Patent Literature

Patent Literature 1: Japanese Patent Application Examined Publication No. Sho. 61-026649 B

Patent Literature 2: Japanese Patent Application Laid-Open No. 2014-168886 A

Patent Literature 1: International Publication No. 2015/178370

SUMMARY

Technical Problem

In recent years, studies on a display device that includes an organic electroluminescent element (hereinafter also referred to as an “organic EL element” as appropriate) have been pursued. The display device that includes the organic EL element is desired to achieve new performance such as foldable and rollable. In order to achieve such performance, there is a demand for developing an electroconductive film having excellent bending resistance while having high electroconductivity.

As an electroconductive film, Patent Literature 1 proposes an electroconductive film that is formed of a styrene-diene-based block copolymer and a thiophene-based copolymer. However, the electroconductive film described in Patent Literature 1 has poor electroconductivity.

Further, as an electroconductive film, Patent Literature 2 proposes a transparent electroconductive film that includes a transparent resin film and an electroconductive layer formed on the transparent resin film. However, the transparent electroconductive film described in Patent Literature 2 has poor bending resistance.

Further, Patent Literature 3 describes an optical film that is formed of a specific hydrogenated product of a block copolymer. Further, Patent Literature 3 describes a transparent electroconductive film as a use application of this optical film. However, Patent Literature 3 does not describe a specific structure of the transparent electroconductive film.

The present invention has been made in view of the aforementioned problems, and an object of the present invention is to provide an electroconductive film having both excellent electroconductivity and excellent bending resistance.

Solution to Problem

As a result of intensive studies to solve the aforementioned problems, the present inventor has found that an electroconductive film having both excellent electroconductivity and excellent bending resistance can be achieved by combining a resin layer having a specific storage elastic modulus at 25° C. with an electroconductive layer having a specific surface resistance value, thereby completing the present invention.

That is, the present invention includes the following aspects.

(1) An electroconductive film comprising a resin layer and an electroconductive layer, whereinthe resin layer has a storage elastic modulus at 25° C. of more than 10 MPa and less than 1,000 MPa, andthe electroconductive layer has a surface resistance value of 1,000 Ω/sq. or less.

(2) The electroconductive film according to (1), wherein the resin layer has a bending elastic modulus at 25° C. of 500 MPa or less.

(3) The electroconductive film according to (1) or (2), whereinthe resin layer contains an alkoxysilyl group-modified product [3] of a hydrogenated product of a block copolymer,the alkoxysilyl group-modified product [3] is an alkoxysilyl group-modified product of a hydrogenated product [2] that is a product of hydrogenation of carbon-carbon unsaturated bonds in a main chain and a side chain and carbon-carbon unsaturated bonds in an aromatic ring of a block copolymer [1],the block copolymer [1] includes two or more polymer blocks [A] per one molecule of the block copolymer [1] and one or more polymer blocks [B] per one molecule of the block copolymer [1], the polymer block [A] containing an aromatic vinyl compound unit, the polymer block [B] containing a chain conjugated diene compound unit, anda ratio (wA/wB) of a weight fraction wA of the polymer blocks [A] in the entire block copolymer [1] and a weight fraction wB of the polymer blocks [B] in the entire block copolymer [1] is in a range of 20/80 to 60/40.

(4) The electroconductive film according to any one of (1) to (3), wherein the electroconductive layer contains at least one type of an electroconductive material selected from the group consisting of a metal, an electroconductive nanowire, and an electroconductive polymer.

Advantageous Effects of Invention

According to the present invention, an electroconductive film having both excellent electroconductivity and excellent bending resistance can be provided.

