Highly insulating film
AssigneeTeijin Limited
InventorsShigeyoshi Masuda, Dai Nakagawa, Kinji Hasegawa, Masanori Nishiyama
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Abstract
Provided is a highly insulating film having excellent electrical characteristics (breakdown voltage), heat resistance, and handling properties such as windability and processability. The highly insulating film is a biaxially stretched film made of a styrene polymer having a syndiotactic structure as a main component. The highly insulating film contains specific inert fine particles A, antioxidant, and polymer Y having a glass transition temperature Tg by DSC of 130° C. or more each in a specific amount, and has a refractive index in the thickness direction of 1.5750 or more and 1.6350 or less.
Claims15
A highly insulating film comprising a biaxially stretched film made of a styrene polymer having a syndiotactic structure as a main component,
- the biaxially stretched film containing:
- inert fine particles A having an average particle size of 0.05 μm or more and 1.5 μm or less with a relative standard deviation in particle size of 0.5 or less in an amount of 0.05 mass % or more and 2.0 mass % or less;
- an antioxidant in an amount of 0.1 mass % or more and 8 mass % or less;
- and
- a polymer Y having a glass transition temperature Tg by DSC of 130° C. or more in an amount of 5 mass % or more and 48 mass % or less,
- the biaxially stretched film having a refractive index in the thickness direction of 1.5750 or more and 1.6350 or less.
Dependencies are inferred from the claim text.