Adhesive formulations
View Patent ↗The present invention relates to adhesive formulations based on uretdione-group-comprising polyaddition compounds that are free of isocyanate groups and monomeric polyisocyanates, and to the use thereof for the production of adhesive bonds between substrates, in particular for the production of flexible film composites.
1. An adhesive formulation consisting of one or more uretdione-group-comprising polyaddition compound that comprising less than 2 wt. % free isocyanate groups and no monomeric polyisocyanates, and which can be used as an adhesive at temperatures of less than 100° C., wherein the uretdione-group-comprising polyaddition compound has a content of isocyanate groups present as uretdione of from 1 to 20 wt. %, a solvent, one or more polyols or a polyol formulation, and one or more additives, including an adhesion promoter, and wherein the solid content of the adhesive formulation is from 20 to 60 wt. %.
2. The adhesive formulation according to claim 1 , wherein the uretdione-group-comprising polyaddition compound is combined with the one or more polyols or the polyol formulation while maintaining an equivalent ratio of uretdione groups to hydroxyl groups of from 0.5:1 to 2.0:1.
3. The adhesive formulation according to claim 1 , wherein the solid content is from 25 to 50 wt. %.
4. The adhesive formulation according to claim 1 , wherein the solid content is from 30 to 40 wt. %.
5. A method for bonding substrates comprising providing the adhesive formulation according to claim 1 , applying the adhesive formulation to at least one substrate, exposing the adhesive formulation on the at least one substrate to a temperature of less than 100° C., and forming a bond between the substrates.
6. The method of claim 5 , wherein the at least one substrate is paper, wood, plastic, metal or stoneware.
7. A process for the production of a film composite comprising applying the adhesive formula according to claim 1 at least partially over a surface of at least two identical or different plastic films and/or metal films, and bonding the films together.
8. A film composite obtained by the process according to claim 7 .