# US 6,723,817 B2 · Polyisocyanates blocked with epsilon-caprolactam and either diisopropylamine or 1,2,4-triazole, their preparation and use

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 6,723,817 B2
- Document ID: US6723817B2
- Status: Granted
- Kind: B2
- Application number: 10/298,773
- Filed: 2002-11-18
- Published: 2003-07-10
- Granted: 2004-04-20
- Earliest claimed: 2001-11-20
- Assignees: Bayer Aktiengesellschaft
- Inventors: Eberhard König; Beate Baumbach; Christian Füssel
- Web page: https://patentgrep.com/patent/US6723817B2

## CPC

- C09D 175/06: from polyesters
- C08G 18/12: using two or more compounds having active hydrogen in the first polymerisation step
- C08G 18/6611: {having at least three hydroxy groups}
- C08G 18/8096: {with two or more compounds having only one group containing active hydrogen}
- Y10T 428/31605: Next to free metal
- C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D)
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

The present invention relates to a blocked polyisocyanate containing: A1) 40 to 70 equivalent % of a predominantly linear NCO prepolymer having an NCO content of 5.0 to 10.0 wt. %, A2) 30 to 60 equivalent % of an aliphatic lacquer polyisocyanate, B1) 30 to 60 equivalent % of epsilon-caprolactam and B2) 40 to 70 equivalent % of diisopropylamine or 1,2,4-triazole as blocking agents, wherein the equivalent percents of isocyanate components A1) and A2) add up to 100 %, and the equivalent percents of blocking agents B1) and B2) add up to 100 to 110%, based on the equivalents of component A). The present invention also relates to a process for preparing these blocked polyisocyanates to coating compositions containing these blocked polyisocyanates and to metal substrates coated with these coating compositions.

## Claims

### Claim 1

A blocked polyisocyanate comprising:
A1) 40 to 70 equivalent % of a predominantly linear NCO prepolymer having an NCO content of 5.0 to 10.0 wt. %,
A2) 30 to 60 equivalent % of an aliphatic lacquer polyisocyanate,
B1) 30 to 60 equivalent % of ε-caprolactam and
B2) 40 to 70 equivalent % of diisopropylamine or 1,2,4-triazole as blocking agents,
wherein the equivalent percents of isocyanate components A1) and A2) add up to 100%, and the equivalent percents of blocking agents B1) and B2) add up to 100 to 110%, based on the equivalents of component A).

### Claim 2 (depends on 1)

A process for the preparation of the hybrid blocked polyisocyanate of claim 1 which comprises
a) preparing NCO prepolymer A1),
b) mixing NCO prepolymer A1) with solvent and lacquer polyisocyanate A2) in an amount such that 40 to 70 equivalent % of the isocyanate groups are present in NCO prepolymer A1) and 30 to 60 equivalent % of the isocyanate groups are present in lacquer polyisocyanate A2),
c) blocking 30 to 60 equivalent % of the isocyanate groups present in the mixture prepared in step b) with ε-caprolactam and
d) blocking the remaining isocyanate groups from component c) with either with 1,2,4-triazole or with diisopropylamine.

### Claim 3 (depends on 1)

A coating composition containing the blocked polyisocyanate of claim 1 and a polyhydroxyl compound.

### Claim 4 (depends on 1)

A metal substrate coated with the coating composition of claim 1.