Nippon Oil Fats Co., Ltd.

Nissan Motor Company Limited

Kazuo Kakinuma

Shosaku Yamamoto

Riichiro Maruta

Junji Mayumi

Fumio Sodeyama

Masashi Ohno

Takashi Toyama

Kiminori Ishii

Hiroshi Ishioka

A primer composition usable for steel sheets and plastic sheets in vehicle bodies consists essentially of a component (A) consisting essentially of at least one resin having a glass transition temperature of not higher than -20.degree. C., preferably not lower than -75.degree. C., and an elongation at break of not less than 400% preferably not greater than 900%, at 20.degree. C. and a component (B) consisting essentially of at least one crosslinking resin, the weight ratio of solid content of (A) to (B) being 70-99:30-1.

Primer compositions

A primer composition usable for steel sheets and plastic sheets in vehicle bodies consists essentially of a component (A) consisting essentially of at least one resin having a glass transition temperature of not higher than -20.degree. C., preferably not lower than -75.degree. C., and an elongation at break of not less than 400%, preferably not greater than 900%, at 20.degree. C. and a component (B) consisting essentially of at least one crosslinking resin, the weight ratio of solid content of (A) to (B) being 70-99:30-1.

A primer composition usable for steel sheet and plastic sheet in vehicle bodies consists essentially of a component A composed of a resin obtained by graft-polymerizing a styrene-butadiene-styrene block copolymer or its hydrogenated polymer with .alpha.,.beta.-unsaturated carboxylic acid or its anhydride, a component B of a crosslinking agent and a component C of an epoxy compound, and has particular weight ratios as solid content of component A to component B and components A+B to component C.

A primer composition usable for steel sheet and plastic sheet in vehicle bodies consists mainly of a polycaprolactone graft polymer obtained by graft-polymerizing a styrene-butadiene-styrene block copolymer or its hydrogenated polymer with a ring-opened polymer of .epsilon.-caprolactone and having a grafting ratio of the ring-opened polymer within a range of 0.5.about.50% by weight.

A primer composition usable for steel sheets and plastic sheets in vehicle bodies consists essentially of a component (A) consisting essentially of at least one resin having a glass transition temperature of not higher than -20.degree. C., preferably not lower than -75.degree. C., and an elongation at break of not less than 400%, preferably not greater than 900%, at 20.degree. C. and a component (B) consisting essentially of at least one crosslinking resin, the weight ratio as solid content of (A) to (B) being 70-99:30-1.

A method for finish coating on polyurethane formed articles, which comprises formulating a finish coating composition so as to have a content of pyrrolidone or its derivative represented by the general formula ##STR1## in which R stands for hydrogen or an alkyl group having at the most 4 carbon atoms, in an amount of 5-40% by weight upon the coating, applying this finish coating composition on the polyurethane formed article directly and heating the so called polyurethane formed article at a temperature of at least 50.degree. C. but lower than the thermal deformation temperature of the polyurethane formed article, said method being capable of attaining a coating layer exhibiting both the properties for a primer coat, namely, a better adhesion onto polyurethane formed articles, and for a finish coat, namely, better weather resistance, higher chemical resistance, favorable appearance and so on, with only a single application and permitting thus to dispense with the primer coating and the heat drying procedure therefor.

Growing community of inventors

Yokohama, Japan

Kazuo Kakinuma