Bayer Aktiengesellschaft

Wolf-Dieter Last

Karlheinz Wolf

Wilfried Zecher

Willi Dunwald

Dietrich Hildebrand

Jurgen Lewalter

Rudolf Saitner

Wilhelm Thoma

Heinrich Rinke

Wilhelm Bunge

A process for the low solvent or solvent free coating of heat resistant substrates by using a coating substance which has a melting point or range below about 200.degree. C and which is heat crosslinkable. The substrate is coated at temperatures between about 20.degree. and 250.degree. C and the coating is subsequently heated to more elevated temperatures to effect crosslinking. The coating substance contains active hydrogen, preferably hydroxyl bearing compounds and blocked polyisocyanates which become reactive when the coating substance is heated to effect cross-linking. In a preferred embodiment, the blocked polyisocyanates consist of at least 40 equivalent percent alkanol or cycloalkanol blocked polyisocyanates. Also a coating substance containing at least 50 wt.% of a combination of active hydrogen, preferably hydroxyl bearing compounds and blocked isocyanates. The combination has a melting point of less than 200.degree. C and a blocked isocyanate group to active hydrogen ratio of about 1:2 to 1:9. At least 40 equivalent percent of the blocked polyisocyanates are alkanol or cycloalkanol blocked and the remainder are blocked such that they are reactive at temperatures at least 30.degree. C lower than the alkanol or cycloalkanol blocked polyisocyanates. The coating substance has a viscosity of less than about 40,000 cP at or below about 250.degree. C.

Melt coating composition and coating process

Pigment preparations containing 3 to 80 percent by weight of an organic or inorganic pigment, 0.5 to 85 percent by weight of a resin containing carbodiimide groups and 0 to 75 percent of an organic solvent free from amino groups are used for pigmenting synthetic high-molecular materials, especially one-component and two-component polyurethane textile coating compositions.

Pigment preparations

This invention relates to the production of basic modified polyamides produced by the polycondensation of lactams or .omega.-aminocarboxylic acids with 0.1 to 5 mol of triamines of the formula

Process for the production of basic modified polyamides

Growing community of inventors

Leverkusen, Germany

Wolf-Dieter Last