Highly insulating film

Patent metadata

Field	Value
Publication number	US-9617407-B2
Application number	US-201214113485-A
Country	US
Kind code	B2
Filing date	Apr 25, 2012
Priority date	Apr 26, 2011
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

This invention is a highly insulating film, which is characterized by including a biaxially stretched film containing a styrene polymer having a syndiotactic structure as a main component, containing a thermoplastic amorphous resin Y having a glass transition temperature Tg by DSC of 130° C. or higher in an amount of 5% by mass or more and 48% by mass or less, and having a plane orientation coefficient (AP) represented by the following equation (1) of −0.027 or less: ΔP=(Nx+Ny)/2−Nz (1). In equation (1), Nx represents the minimum value of the refractive index in the plane direction of the film, Ny represents the refractive index in the direction perpendicular to Nx in the plane direction of the film, and Nz represents the refractive index in the thickness direction of the film.

First claim

The invention claimed is:

1. A highly insulating film, which is characterized by comprising a biaxially stretched film containing a styrene polymer having a syndiotactic structure as a main component, containing a thermoplastic amorphous resin Y having a glass transition temperature Tg by DSC of 130° C. or higher in an amount of 5% by mass or more and 48% by mass or less, and having a plane orientation coefficient (AP) represented by the following equation (1) of −0.027 or less and −0.040 or more:
Δ P =( Nx+Ny )/2− Nz   (1)

(in the equation (1), Nx represents the minimum value of the refractive index in the plane direction of the film, Ny represents the refractive index in the direction perpendicular to Nx in the plane direction of the film, and Nz represents the refractive index in the thickness direction of the film),
wherein the polymer Y is polyphenylene ether represented by the following formula (A),

(each of Q1 and Q2 in the above formula (A) is at least one kind selected from the group consisting of methyl, ethyl and propyl),
wherein the film contains an antioxidant in an amount of 0.1% by mass or more and 8% by mass or less relative to the mass of the biaxially stretched film,
wherein the content ratio of the polymer Y and the antioxidant (the polymer Y content/the antioxidant content) is 1 to 100,
wherein a refractive index in thickness direction of the biaxially stretched film is 1.600 or more and 1.610 or less, and
wherein the highly insulating film has a breakdown voltage at 120° C. of 400 V/μm or more.

2. The highly insulating film described in claim 1 , wherein the thermal decomposition temperature of the antioxidant is 250° C. or higher.

3. The highly insulating film described in claim 1 , wherein the absolute value of the difference between the minimum value of the refractive index in the plane direction of the film (Nx) and the refractive index in the direction perpendicular to the direction (Ny) is 0.025 or less.

4. The highly insulating film described in claim 1 , wherein the biaxially stretched film contains an inert fine particle having an average particle diameter of 0.05 μm or more and 3.0 μm or less in an amount of 0.05% by mass or more and 3% by mass or less relative to the mass of the biaxially stretched film.

5. The highly insulating film described in claim 1 , wherein the biaxially stretched film has a coating layer, which is provided on at least one side of the biaxially stretched film and has a water contact angle of the surface of 85° or more and 120° or less.

6. The highly insulating film described in claim 5 , wherein the coating layer contains at least one kind selected from the group consisting of a wax component, a silicone component and a fluorine compound in an amount of 41% by mass or more and 94% by mass or less based on the mass of the coating layer.

7. The highly insulating film described in claim 6 , wherein the coating layer contains a wax component, and the wax component is polyolefin wax.

8. The highly insulating film described in claim 5 , wherein the thickness of the coating layer is in the range of 0.005 to 0.5 μm.

9. The highly insulating film described in claim 1 , wherein the thickness of the highly insulating film is 0.4 μm or more and less than 6.5 μm.

Assignees

• Nakahiro Takashi
• Nakagawa Dai
• Yoshida Tetsuo
• Nishiyama Masanori
• Teijin Ltd

Inventors

• Nakahiro Takashi
• Nakagawa Dai
• Yoshida Tetsuo
• Nishiyama Masanori

Classifications

• B29K2071/12

  PPO, i.e. polyphenylene oxide; PPE, i.e. polyphenylene ether · CPC title

• C08J2471/12

  Polyphenylene oxides · CPC title

• Y10T428/31663

  As siloxane, silicone or silane · CPC title

• H01B17/56

  Insulating bodies · CPC title

• C08J5/18 Primary

  Manufacture of films or sheets · CPC title