Film, method for producing film, metal-clad laminate, and coated metal conductor

Patent metadata

Field	Value
Publication number	US-12119142-B2
Application number	US-202217591755-A
Country	US
Kind code	B2
Filing date	Feb 3, 2022
Priority date	Aug 27, 2019
Publication date	Oct 15, 2024
Grant date	Oct 15, 2024

Abstract

A heat-resistant film that has high adhesion and low warping, a method for producing the film, and a metal-clad laminate and a coated metal conductor, using the film. The film includes an aromatic polyimide base film, and a layer containing a polymer having units based on tetrafluoroethylene and units based on a perfluoro(alkyl vinyl ether) and an aromatic polymer, formed on each side of the base film.

First claim

What is claimed is:

1. A film comprising an aromatic polyimide base film, and a layer containing (i) a polymer having units based on tetrafluoroethylene and units based on a perfluoro(alkyl vinyl ether) and (ii) an aromatic polymer, formed on each side of the base film,
wherein in the layer, an amount of the aromatic polymer (ii) to a total amount of the polymer (i) and the aromatic polymer (ii) is 10 mass % or less.

2. The film according to claim 1 , wherein the base film and each layer are directly in contact with each other.

3. The film according to claim 1 , wherein the polymer is a polymer having units based on tetrafluoroethylene and units based on a perfluoro(alkyl vinyl ether), and having a polar functional group, or a polymer having units based on tetrafluoroethylene and units based on a perfluoro(alkyl vinyl ether) in a proportion of the units based on a perfluoro(alkyl vinyl ether) of from 2.0 to 5.0 mol % to all units, and having no functional polar group.

4. The film according to claim 1 , wherein the aromatic polymer is an aromatic polyimide.

5. The film according to claim 1 , wherein polar functional groups are present at the surface of the layer.

6. The film according to claim 1 , wherein the film has a thickness of 25 μm or more, and the ratio of the total thickness of the two layers to the thickness of the base film is 1 or more.

7. The film according to claim 1 , which has a water absorption coefficient of 0.1% or lower.

8. The film according to claim 1 , which has an optical absorption coefficient at a wavelength of 355 nm of 50% or higher.

9. The film according to claim 1 , which has a loss tangent of less than 0.003.

10. A metal-clad laminate, comprising the film as defined in claim 1 , and a metal foil bonded to each side of the film.

11. A coated metal conductor, comprising a metal conductor, and the film as defined in claim 1 formed to coat the metal conductor.

12. A method for producing a film, which comprises applying a powder dispersion containing a powder of a polymer having units based on tetrafluoroethylene and units based on a perfluoro(alkyl vinyl ether), an aromatic polymer or its precursor, and a liquid medium, to the surface of an aromatic polyimide base film, followed by heating to form a layer, thereby to obtain a film having the layer formed on each side of the base film,
wherein in the layer, an amount of the aromatic polymer to a total amount of the polymer having units based on tetrafluoroethylene and units based on a perfluoro(alkyl vinyl ether) and the aromatic polymer is 10 mass % or less.

13. The production method according to claim 12 , wherein the powder dispersion further contains a thermally decomposable nonionic surfactant.

14. The production method according to claim 12 , wherein heating is conducted in an atmosphere containing an oxygen gas to form the layer.

Assignees

• Agc Inc

Inventors

• Kasai Wataru
• Hosoda Tomoya
• MITSUNAGA Atsumi
• Terada Tatsuya
• Yuki Sota

Classifications

• H01B3/445

  from vinylfluorides or other fluoroethylenic compounds · CPC title

• H01B1/026

  Alloys based on copper · CPC title

• B32B2457/04

  Insulators · CPC title

• B32B2307/7265

  Non-permeable · CPC title

• B32B2307/206

  Insulating · CPC title