Concentrated microcapsule suspensions for reaction copying papers

US4428978A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gert Jabs
• Gunther Baatz · Cologne, DE
• Manfred Bock · Leverkusen, DE
• Manfred Dahm · Leverkusen, DE
• Artur Haus · Leverkusen, DE
• Christian Wegner · Cologne, DE

Key dates

• Filing date: May 20, 1981
• Grant date: Jan 31, 1984
• Expiry date: May 20, 2001

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B41M5/165
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A process for the production of aqueous suspensions containing from 35 to 60% by weight of microcapsules by interfacial polyaddition from polyisocyanates and H-active compounds, wherein PA0 (a) an isocyanaurate-modified aliphatic polyisocyanate is used as the polyisocyanate, and PA0 (b) the suspension is adjusted to a pH-value of .ltoreq.7 after the polyaddition reaction, which microcapsules optimally contain dye precursors and can be used for the production of completely or partly coated copying systems by the rotogravure or flexograph processes.