| abstract |
The invention described in detail herein includes a group of radiation curable coating formulations, particularly for metal substrates. These coating formulations include acrylate monomers and β-ketoesters (eg, acetoacetates), β-diketones (eg, 2,4-pentanedione), β-ketoamides (eg, acetoacetamide), and / or Michael additions. It is based on polyfunctional acrylate resins formed by reaction with other β-dicarbonyl compounds that can participate in the reaction. The essential novelty of these coating resins is that they cure under normal UV curing conditions without the addition of conventional photoinitiators. Other materials, both reactive (ordinary acrylates) and non-reactive (eg, solvents) may be incorporated into the resin oligomer to enhance the coating properties on the metal substrate. These materials include various acrylic monomers and oligomers, primary, secondary, and tertiary amines, acid functional monomers and oligomers, silicones, waxes, elastomers, and others. These new multifunctional acrylate resin-based coatings offer excellent adhesion and shrinkage control, flexibility, solvent resistance, scratch and damage resistance, impact resistance, color, and durability in a wide range of plastics Show through material. These coatings can be cured by chemical means or by exposure to UV or electron beam radiation. |