Nippon Paint Compnay, Ltd.

Kunihiko Takeuchi

Yasuhiro Shibata

Keizou Ishii

Hisaki Tanabe

Hidefumi Okuda

Tadahiko Nishi

Tsuyoshi Imamura

Hideaki Ogawa

Katsuhiko Sho

An aqueous coating composition comprising: (A) 10 to 95% by weight (based on solid content) of a film forming polymer which is prepared by neutralizing at least a part of acid groups contained in a copolymer having a number average molecular weight ranging from 6,000 to 50,000 prepared by copolymerizing (A1) 5 to 40% by weight of an amide group-containing ethylenically unsaturated monomer, (A2) 3 to 15% by weight of an acid group-containing ethylenically unsaturated monomer, (A3) 10 to 40% by weight of a hydroxyl group-containing ethylenically unsaturated monomer, and (A4) a remainder amount of ethylenically unsaturated monomers other than the monomers (A1) to (A3); and (B) 5 to 90% by weight (based on solid content) of an aqueous dispersion of carboxyl group-containing acrylic resin particles having a particle size ranging from 0.01 to 1.0 .mu.m and an acid value ranging from 20 to 80. An aqueous metallic-base coating composition which enables to form a coating film of an improved appearance at a high workability almost free from 'sagging' and 'unevenness' is provided.

Aqueous coating composition

The present invention provides the improvement of coating workability (e.g. pinhole resistance, sagging resistance, etc.) of an aqueous coating composition. That is, the present invention provides an aqueous coating composition which comprises: (A) an acrylic resin and/or a polyester resin having an acid value of 10 to 100, a hydroxyl value of 20 to 300 and a number average-molecular weight of 1,000 to 50,000; (B) a polycarbonate resin having a number average-molecular weight of 1,000 to 10,000 which contains a hydroxyl group at the terminal end; and (C) a curing agent.

Aqueous coating composition and coating process using the same

There is provided a two-coat, one-bake metallic coating method which comprises applying, first, (a) a base coat composition containing an acrylic polyol oligomer having an average molecular weight of 500 to 2000 and a non-yellowing polyisocyanate compound in a NCO/OH ratio of 0.5/1 through 1/0.5 and further containing an appropriate amount of a metallic pigment and, then, on top thereof (b) a clear top coat composition containing said acrylic polyol oligomer and non-yellowing polyisocyanate compound in a NCO/OH ratio of 0.5/1 through 1/0.5 and causing the resulting coats to cure simultaneously. There are also provided coating compositions to be used in the above coating method.

Metallic coating using two coat one bake method

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Mino, Japan

Kunihiko Takeuchi