Patent ID: 9403954
Filing Date: 2016-08-02
CPC Classification: B29B,C08J,C08K

Claim Text:
1. A fluororubber composition comprising: a fluororubber (A); and carbon black (B); and a crosslinking agent (C) and/or a crosslinking accelerator (D), wherein when the fluororubber composition in an uncrosslinked state is immersed for 160 hours in an extraction solvent of acetone and hexane at an acetone:hexane mass ratio of 42.29:57.71 at 40° C. and extraction residue that is not extracted and remains as a solid is separated from the aforementioned extraction solvent and dried and then the dry weight of the extraction residue is measured, the quantity of a solvent-insoluble polymer, as calculated using the expression below, is not lower than 5%: (where, w is an initial weight (g) of the fluororubber composition which is immersed in the extraction solvent, w′ is a dry weight (g) of the extraction residue, φ p is an initial weight fraction of the fluororubber (A) contained in the fluororubber composition which is immersed in the extraction solvent relative to the fluororubber composition, and φ p ′ is a weight fraction of the fluororubber (A) contained in the extraction residue relative to the extraction residue).