Coating composition, undercoating composition, multilayer body having coating film made of such composition, photocatalyst coating film, and molded body

A coating composition comprising at least one organic-inorganic hybrid polymer (A) and at least one polysiloxane (B),

• wherein said organic-inorganic hybrid polymer (A) is prepared by adding a catalyst (c) for accelerating hydrolysis and condensation and water (d) to a mixture of at least one silane compound (a) and a polymer (b),
• wherein said at least one silane compound (a) is selected from the group consisting of at least one organosilane represented by formula (1), a hydrolysate of said organosilane and a condensate of said organosilane:
• R1nSi(OR2)4−n (1)
• wherein
• each R1 group independently represents a monovalent organic group having 1 to 8 carbon atoms;
• each R2 group independently represents an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 6 carbon atoms;
• and
• n is an integer of 0 to 2,
• wherein said polymer (b) has a silyl group containing a silicon atom bonded to at least one of a hydrolysable group and a hydroxyl group, and
• wherein the weight ratio (Wa/Wb) of the content (Wa) of the silane compound (a) in said mixture in terms of the completely hydrolyzed condensate to the content (Wb) of the polymer (b) in said mixture in terms of the solid content is in the range from 5/95 to 50/50, provided that Wa+Wb=100;
• wherein said polysiloxane (B) has a weight-average molecular weight of 800 to 50,000 and is represented by average composition formula (2),
• R3aSiOb(OH)c(OR4)d(Y)e (2)
• wherein
• each R3 group independently represents an organic group having 1 to 8 carbon atoms;
• each R4 group independently represents an organic group selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, an acyl group having 1 to 6 carbon atoms, and a phenyl group;
• R3 and R4 are the same or different from each other;
• Y represents a halogen atom or a hydrogen atom;
• and
• a, b, c, d, and e each independently is not less than 0 and not more than 4 and they satisfy a+b/2+c+d+e=4.