A polyol-crosslinkable fluororubber composition comprises 100 parts by
weight of polyol-crosslinkable fluororubber; 0.5 to 10 parts by weight of
a perfluoroalkane represented by the general formula F(CF.sub.2).sub.2nF
(n: 5.about.30), a 1H-perfluoroalkane represented by the general formula
F(CF.sub.2).sub.mH (m: 10.about.30), or a mixture thereof; 0.5 to 2 parts
by weight of basic magnesium aluminum hydroxycarbonate hydrate; and 1 to
5 parts by weight of an acid acceptor compound excluding Ca compounds.
The fluororubber composition can simultaneously attain improvement in
preservation stability of compounds, prevention of compounds from
adhesion at the time of kneading, short-time vulcanization, improvement
of mold releasability at the time of vulcanization molding, prevention of
contamination with metal ions and reduction in adhesiveness of
crosslinking products due to increase of crosslinking density without
substantially impairing the normal state physical properties or
compression set characteristics and further advantage-ous properties
inherent in the fluororubber, and contains no calcium compounds causing
contamination of HDD.