Siloxane polymer antifouling paint composition containing polysiloxanes

An antifouling paint composition comprising as a film-forming component a vinyl-type copolymer obtained by copolymerization of

• (A) 1 to 50% by weight of a polymerizable unsaturated polysiloxane compound represented by the formula ##STR26## wherein X.sub.1 represents a group of the formula ##STR27## where R.sub.6 represents a hydrogen atom or a methyl group;
• R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are identical or different and each represents an alkyl group having 1 to 4 carbon atoms, an aryl group or an aralkyl group;
• R.sub.5 represents a hydroxyalkyl group having 1 to 3 hydroxyl groups and 1 to 6 carbon atoms;
• a is 0 when X.sub.1 represents the group ##STR28## and an integer of 1 to 5 when X.sub.1 represents the group ##STR29## and b is a number of 3 to 1,000,
• (B) 0 to 30% by weight of a polymerizable unsaturated alkoxysilane compound represented by the formula ##STR30## wherein X.sub.2 represents a group of the formula ##STR31## where R.sub.8 represents a hydrogen atom or a methyl group;
• R.sub.7 represents an alkyl group having 1 to 4 carbon atoms;
• and
• d is 0 when X.sub.2 represents the group ##STR32## and an integer of 1 to 5 when X.sub.2 represents the group ##STR33## and (C) 20 to 99% by weight of a polymerizable unsaturated vinyl monomer other than the compounds (A) and (B) above,
• and further comprising 1 to 50 parts by weight, per 100 parts by weight of the vinyl-type copolymer, of a siloxane compound represented by the formula:
• ##STR34## wherein R.sub.10, R.sub.11, R.sub.12 and R.sub.13 are identical or different, and each represents an alkyl group having 1 to 4 carbon atoms, an aryl group or an aralkyl group;
• p is an integer of 1 to 5;
• and
• q is a number of 3 to 1,000 "and said composition being free of silanol-containing compounds".