Highly concentrated stable solutions of color-forming agent: for pressure-sensitive recording materials

US4923641A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Udo Eckstein · Cologne, DE
• Hubertus Psaar · Leverkusen, DE

Key dates

• Filing date: Sep 20, 1988
• Grant date: May 8, 1990
• Expiry date: Sep 20, 2008

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B41M5/1366
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

Highly concentrated stable solutions of color-forming agents of the general formula ##STR1## wherein x denotes hydroxyl, alkoxy, alkenyloxy, aralkoxy, cycloalkoxy, aryloxy, acyloxy, alkylamino, dialkylamino, acylamino, aralkylamino or arylamino and PA1 R denotes alkyl, alkenyl or aralkyl, further isocyclic or heterocyclic rings can be fused onto the rings A, B, C and D and the cyclic and acyclic radicals and the rings A, B, C and D can carry further non-ionic substituents which are customary in dyestuff chemistry, or mixtures thereof, in water-insoluble organic solvents from the group comprising optionally chlorinated hydrocarbons, vegetable oils and phthalic acid esters are used for the preparation of pressure-sensitive recording materials.