CN-116941347-B - Conductive piezoelectric laminated film and method for producing same

Abstract

The invention provides a conductive piezoelectric laminated film with high transparency. The conductive piezoelectric laminated film (10) is formed by sequentially superposing a first coating layer (2) having a refractive index of 1.45 or more and less than 1.60, a second coating layer (3) having a refractive index of 1.60 or more and less than 1.80, and a conductive layer (4) having a refractive index of 1.80 or more and 2.20 or less on at least one surface of a piezoelectric film (1) having a refractive index of 1.30 or more and 1.50 or less.

Inventors

• JIN ZHICHENG
• SHAN KOUHUI

Assignees

• 株式会社吴羽

Dates

Publication Date

20260505

Application Date

20220210

Priority Date

20210319

Claims (8)

1. 1. A conductive piezoelectric laminated film is formed by sequentially laminating a first coating layer, a second coating layer, and a conductive layer on at least one surface of a piezoelectric film, The piezoelectric film has a refractive index of 1.30 or more and 1.50 or less, The refractive index of the first coating is 1.45 or more and less than 1.60, The refractive index of the second coating is 1.60 or more and less than 1.80, The conductive layer has a refractive index of 1.80 or more and 2.20 or less, The refractive index of the first coating layer is higher than that of the piezoelectric film.
2. 2. The conductive piezoelectric laminated film according to claim 1, wherein, b*≤4。
3. 3. The conductive piezoelectric laminated film according to claim 1 or 2, wherein, The transmittance at a wavelength of 550nm is 83% or more.
4. 4. The conductive piezoelectric laminated film according to claim 1 or 2, wherein, The haze value is 2.0% or less.
5. 5. The conductive piezoelectric laminated film according to claim 1 or 2, wherein, The conductive layer is composed of an indium-tin composite oxide, No peak of the indium-tin composite oxide in X-ray diffraction was detected.
6. 6. An apparatus provided with a conductive piezoelectric laminate film according to any one of claims 1 to 5.
7. 7. A method for producing a conductive piezoelectric laminated film, wherein, The conductive piezoelectric laminated film is formed by sequentially superposing a first coating layer, a second coating layer and a conductive layer on at least one surface of the piezoelectric film, The method for manufacturing the conductive piezoelectric laminated film comprises the following steps: a first step of forming a film having a refractive index of 1.30 or more and 1.50 or less to produce a piezoelectric film; A second step of forming a first coating layer having a refractive index of 1.45 or more and less than 1.60 on at least one surface of the piezoelectric film; A third step of forming a second coating layer having a refractive index of 1.60 or more and less than 1.80 on the surface of the first coating layer, and And a fourth step of forming a conductive layer having a refractive index of 1.80 or more and 2.20 or less on the surface of the second coating layer.
8. 8. The method for producing a conductive piezoelectric laminated film according to claim 7, wherein, The annealing treatment of the conductive layer is not performed after the fourth step.

Description

Conductive piezoelectric laminated film and method for producing same Technical Field The present invention relates to a conductive piezoelectric laminated film and a method for producing the same. Background As a device capable of inputting information by direct contact with an image display portion, a touch panel is widely used. As this representative form, there is a capacitive touch panel that uses a change in current capacity generated between an electrode and a finger. The conductive film used as a touch panel is required to have high transparency and to suppress the generation of color tone. As such a conductive film, for example, patent documents 1 and 2 disclose conductive films. In the conductive films disclosed in patent documents 1 and 2, a polyethylene terephthalate (PET) film is used as a base film, and an indium-tin composite oxide (ITO) film is used as a conductive film, and the crystallinity of the ITO is improved by a heat treatment at about 150 ℃. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2017-074792 Patent document 2 Japanese patent application laid-open No. 2013-25737 Disclosure of Invention Problems to be solved by the invention In recent years, technical attention has been paid to simultaneously sensing a position where a finger or the like touches an operation surface and a pressing of the operation surface by the finger or the like, and it has been proposed to realize the detection by a pressing detection sensor constituted by a piezoelectric sensor. However, when the piezoelectric film used for the piezoelectric sensor is subjected to a heating treatment at a high temperature as in the case of the PET film, the color tone is impaired. Therefore, there is a problem in that it is difficult to use a conductive piezoelectric laminated film having a piezoelectric film in a touch panel. On the other hand, when an amorphous conductive film is used without heat treatment, there is a problem that a yellow tone of the self-conductive film is generated in the conductive piezoelectric laminated film. An object of one embodiment of the present invention is to realize a film having high transparency and an appropriate color tone in a conductive piezoelectric laminated film having a piezoelectric film. Technical proposal In order to solve the above problems, the conductive piezoelectric laminated film of the present invention is configured by sequentially laminating a first coating layer, a second coating layer, and a conductive layer on at least one surface of a piezoelectric film, wherein the refractive index of the piezoelectric film is 1.30 or more and 1.50 or less, the refractive index of the first coating layer is 1.45 or more and less than 1.60, the refractive index of the second coating layer is 1.60 or more and less than 1.80, and the refractive index of the conductive layer is 1.80 or more and 2.20 or less. In order to solve the above problems, the conductive piezoelectric laminate film produced by the method for producing a conductive piezoelectric laminate film according to one aspect of the present invention is a laminate film comprising a first coating layer, a second coating layer, and a conductive layer sequentially stacked on at least one surface of a piezoelectric film, and the method comprises a first step of producing a piezoelectric film by forming a film having a refractive index of 1.30 or more and 1.50 or less, a second step of forming a first coating layer having a refractive index of 1.45 or more and less than 1.60 on at least one surface of the piezoelectric film, a third step of forming a second coating layer having a refractive index of 1.60 or more and less than 1.80 on a surface of the first coating layer, and a fourth step of forming a conductive layer having a refractive index of 1.80 or more and 2.20 or less on a surface of the second coating layer. Advantageous effects The present invention can realize a film having high transparency and an appropriate color tone in a conductive piezoelectric laminated film having a piezoelectric film. Drawings Fig. 1 is a cross-sectional view of a conductive piezoelectric laminate film 10 according to an embodiment of the present invention. Fig. 2 is a cross-sectional view of a modification 10' of the conductive piezoelectric laminated film 10 according to the embodiment of the present invention. Detailed Description Hereinafter, embodiments of the present invention will be described in detail. [ Structure of conductive piezoelectric laminate film ] The conductive piezoelectric laminated film according to one embodiment of the present invention is configured by sequentially laminating a first coating layer, a second coating layer, and a conductive layer on at least one surface of a piezoelectric film. The piezoelectric film has a refractive index of 1.30 to 1.50, the first coating layer has a refractive index of 1.45 to less than 1.60, the second coating layer has a refra