PROCESS FOR THE PREPARATION OF POWDER COATINGS ON HEAT-SENSITIVE SUBSTRATES

摘要

A process for the preparation of powder coatings on substrates comprising the following steps of a) applying a powder coating composition onto the substrate surface comprising 40 to 90 wt% of at least one epoxy resin having an epoxy equivalent weight in the range of 1000 to 5,000, 10 to 60 wt% of at least one cross-linking (curing) agent, 0.1 to 15 wt% of at least one inclusion catalyst and 0.01 to 40 wt% of at least one constituent selected from the group consisting of additives, pigments and/or fillers conventional in powder coating technology, the wt% based on the weight of the powder coating composition, b) fusing, melting and flowing out the particles of the powder coating composition under increased temperature to a molten coating, and c) curing the molten coating; The invention provides coatings resulting in one-component stable powder coatings that form smooth and up to fine texture coatings and have improved flow and eliminate post-cure edge cracking and have a high opacity, hardness and flexibility.