Curable composition

Claim 1

A curable composition comprising (A) 100 parts by weight of a oxypropylene polymer having a group represented by the following formula (2): wherein R 4 represents an alkyl group having from 1 to 20 carbon atoms, an aryl group having from 6 to 20 carbon atoms, an aralkyl group having from 7 to 20 carbon atoms, or a triorganosiloxy group represented by the formula (R') 3 SiO- (wherein R' represents a monovalent hydrocarbon group having from 1 to 20 carbon atoms and three R's may be the same or different), when two or more R 4 exist, they may be the same or different; X represents a hydroxy group or a hydrolyzable group, when two or more Xs exist, they may be the same or different; a represents 0 or an integer of from 1 to 3; with the proviso that formula (2) is not (CH 3 O) 2 (CH 3 )Si-, a Mw/Mn value of not more than 1.5, and an average molecular weight of at least 10,000, (B) from 100 to 200 parts by weight of calcium carbonate containing at least 30% by weight calcium carbonate of an average particle size of not larger than 0.5 µm, and surface-treated with a fatty acid, (C) from 30 to 100 parts by weight of a plasticizer containing at least 5% by weight phthalic acid ester plasticizer, (D) from 0.5 to 10 parts by weight of a compound represented by the formula R 1 Si(OCH 3 ) 3 and/or Si(OCH 2 CH 3 ) 4 (wherein R 1 represents a monovalent organic groups containing no amino group), (E) from 0.5 to 10 parts by weight of a compound represented by following formula (1), R 2 Si(CH 3 ) n (OR 3 ) 3-n wherein R 2 represents a monovalent organic group having at least one amino group; R 3 represents CH 3 or CH 2 CH 3 ; and n represents 0 or 1 and (F) from 0.5 to 5 parts by weight of an organotin curing catalyst, the total amount of said components (D) and (E) being at least 2 parts by weight, and said component (A) occupying from 15 to 35% by weight.