Back to results
US 7,300,997 B2Granted
High-reactivity polyurethane powder coating compositions based on epoxy-terminated polyaddition compounds containing uretdione groups
AssigneeDegussa AG
InventorsAndreas Wenning, Emmanouil Spyrou
Life of this patent
Estimating the term…
Abstract
Polyurethane powder coating compositions based on epoxy-terminated polyaddition compounds having uretdione groups, which cure at low baking temperatures, a process for preparing such compositions, and their use for producing plastics, especially polyurethane powder coatings, which crosslink at low baking temperatures to give high-gloss or matt, light-stable and weather-stable coating films.
Claims19
A polyurethane powder coating composition comprising
- A) at least one epoxy-terminated polyaddition compound having one or more uretdione groups which has a melting point of from 40 to 130° C., a number-average molar mass of between 1,000 and 15,000, and a free isocyanate group content calculated as NCO with a molecular weight=42 of from 0 to 2% by weight;
- B) at least one hydroxyl-containing polymer having a melting point of from 40 to 130° C. and an OH number of from 20 to 200 mg KOH/g;
- and
- C) at least one catalyst selected from the group consisting of a metal acetylacetonate, a metal hydroxide, a metal alkoxide, a quaternary ammonium hydroxide, a quaternary ammonium fluoride, and a quaternary ammonium carboxylate;
- wherein from 0.3 to 1 uretdione group of component A) are present for each hydroxyl group of component B), and
- the catalyst C) is present in an amount of from 0.001 to 3% by weight based on the total amount of components A) and B).
3 more elements
A process for preparing a polyurethane powder coating composition comprising
- mixing at least A), B), and C) in a heatable apparatus at a temperature of no more than 130° C.,
- A) at least one epoxy-terminated polyaddition compound having one or more uretdione groups which has a melting point of from 40 to 130° C., a number-average molar mass of between 1,000 and 15,000, and a free isocyanate group content calculated as NCO with a molecular weight=42 of from 0 to 2% by weight;
- B) at least one hydroxyl-containing polymer having a melting point of from 40 to 130° C. and an OH number of from 20 to 200 mg KOH/g;
- and
- C) at least one catalyst selected from the group consisting of a metal acetylacetonate, a metal hydroxide, a metal alkoxide, a quaternary ammonium hydroxide, a quaternary ammonium fluoride, and a quaternary ammonium carboxylate;
- wherein from 0.3 to 1 uretdione group of component A) are present for each hydroxyl group of component B), and the catalyst C) is present in an amount of from 0.001 to 3% by weight based on the total amount of A) and B).
3 more elements
A method comprising
- applying a polyurethane powder a coating composition to a substrate and then curing the coating composition present on the susbstrate;
- wherein the coating composition comprises
- A) at least one epoxy-terminated polyaddition compound having one or more uretdione groups which has a melting point of from 40 to 130° C., a number-average molar mass of between 1,000 and 15,000, and a free isocyanate group content calculated as NCO with a molecular weight=42 of from 0 to 2% by weight;
- B) at least one hydroxyl-containing polymer having a melting point of from 40 to 130° C. and an OH number of from 20 to 200 mg KOH/g;
- and
- C) at least one catalyst selected from the group consisting of a metal acetylacetonate, a metal hydroxide, a metal alkoxide, a quaternary ammonium hydroxide, a quaternary ammonium fluoride, and a quaternary ammonium carboxylate;
- wherein from 0.3 to 1 uretdione group of component A) is present for each hydroxyl group of component B), and the catalyst C) is present in an amount of from 0.00 1 to 3% by weight based on the total amount of components A) and B),
- to form a coating on a substrate.
5 more elements
Dependencies are inferred from the claim text.