Title:
PRODUCTION OF BLOCKED URINE GROUP-CONTAINING POLYISOCYANATE
Document Type and Number:
Japanese Patent JPH01160950
Kind Code:
A
Abstract:
Direct reaction of polyisocyanates and polyamines occurs vigorously and uncontrollably. It is therefore necessary to use the polyisocyanate in blocked form. In previously known processes, it has not been possible to obtain the desired semi-blocked adducts; instead, relatively large portions of completely blocked product in addition to unreacted polyisocyanate were obtained. The further reaction with polyamines was unsuccessful.
The preparation of blocked, urea-containing polyisocyanates has been made possible by using semi-blocked polyisocyanates, which are formed by the addition of blocking agent to a manifold excess of polyisocyanate, followed by thin-film distillation and subsequent reaction with polyamines in an NCO/amino group ratio of 1 to 1.3:1 to 1.1.
The blocked, urea-containing polyisocyanates are used in particular for PUR paints.
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Inventors:
RAINERU GURAASU
Application Number:
JP29031488A
Publication Date:
June 23, 1989
Filing Date:
November 18, 1988
Export Citation:
Assignee:
HUELS CHEMISCHE WERKE AG
International Classes:
C07C67/00; C07C239/00; C07C275/04; C07C275/14; C07C275/26; C07D251/34; C08G18/78; C08G18/80; (IPC1-7): C07C127/00; C08G18/80
Attorney, Agent or Firm:
Mitsuyoshi Ezaki (1 person outside)