Coating compositions containing solvents and crosslinking agents and their use for heat-activated one-coat reverse coating

US4588761A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Wilhelm Thoma · Leverkusen, DE
• Josef Pedain · Cologne, DE
• Walter Schroer · Leverkusen, DE
• Waldemar Kling · Kandern, DE

Key dates

• Filing date: Apr 11, 1984
• Grant date: May 13, 1986
• Expiry date: Apr 11, 2004

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09D175/04
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

This invention relates to PU-coating compositions containing solvent and combinations of crosslinking agents and to a process for producing polyurethane coatings on the principle of heat-activated, one-coat reverse coating by knife-coating the polyurethane coating composition onto a temporary support, drying the layer and laminating the textile substrates using preferably heated pressure rollers, followed by heating at elevated temperatures, the coating compositions used being solvent-containing, 20 to 60% compositions of a polyurethane mixture I containing PA1 (A) relatively soft polyurethanes and PA1 (B) relatively hard one-component polyurethanes and a crosslinker combination II containing PA1 (C) formaldehyde-urea and/or formaldehyde-melamine resins and crosslinking catalysts and PA1 (D) aliphatic and/or aromatic polyisocyanates, particularly blocked polyisocyanates, and, optionally, additions of soluble cellulose esters, handle-improving agents, optionally polysiloxanes containing oxyalkylene groups and other standard additives, such as pigments. The heat-active one-coat reverse coatings obtained in this way show surprisingly high dry and wet adhesion values on textile substra…