EP0004069B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Process for the preparation of aqueous solutions or dispersions of polyurethanes and their use for the preparation of coatings or lacquers
Assignee: Bayer AG
•
Filing: 1979-03-07
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Granted: 1981-08-05
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Expires: 1999-03-07
Abstract
No abstract record available.
Inventors
- 👤 Klaus Dr. Nachtkamp
- 👤 Josef Dr. Pedain
- 👤 Jürgen Dr. Grammel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 05:23
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/2805; C08G18/2815; C08G18/283; C08G18/08; C08G18/0804; C08G18/10; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
2 words
Patent Claims
Claim 2
Dependent Claim
80 words
Process for the preparation of aqueous solutions or dispersions of polyurethanes by reacting prepolymers containing chemically incorporated hydrophilic groupings and/or external emulsifiers which are not chemically bonded, and having at least 2 free isocyanate groups, with chain-lengthening agents in an aqueous phase, characterised in that the prepolymer which is hydrophilically modified and/or contains an external emulsifier and which has isocyanate groups is mixed with azines and/or hydrazones in the absence of water, and this mixture is then mixed with water.
Claim 3
Dependent Claim
50 words
Process according to Claim 1, characterised in that the nature and proportions of the reactants are chosen such that 0.25 to 1.5 hydrazinic NH 2 groups which are reactive towards isocyanate groups and are at least partially blocked are present for each isocyanate group of the prepolymer containing isocyanate groups.
Claim 4
Dependent Claim
21 words
Use of the solutions or dispersions obtainable according to Claims 1 and 2 for the production of coverings, lacquers and coatings.
References Cited (Backward Citations)
No citation records indexed.
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