Waterborne Uv Varnish Is Developed

Coating technology is one of the trends of surface treatment technology of printed matter. As the new coating material, water-base UV varnish has been the target which is the developed country studied in recent years because of its environmental protection, low cost and excellent coating effects, etc.The water-base UV coating material has been early developed in abroad and is mainly used in wood coating but is hardly used in printing. And its development in china is on the initial stage. There is very important to develop water-base UV varnish and study the performances for the development of the water-base UV coating material.The water-base UV varnish system designed was composed of pre-polymer, monomer, photo-initiator and promoter. By changing the type and proportion of pre-polymer, monomer, photo-initiator and promoter, the performances of water-base UV varnish were studied. Through the formulation experiment to make sure the proportions of mixed monomers and to optimize the formulation of water-base UV varnish. The characteristics of water-base UV varnish was studied through coating; the weather-ability was studied through testing the characteristics of samples which were cured.The results show that:the type and proportion of photo-initiator has great effects on the curing rate of water-base UV varnish, the best photo-initiator is 907, and the best content is 6%; the volume shrinkage has great effects on the adhesion, the smaller is the volume shrinkage, the better adhesion of water-base UV varnish is;the type of pre-polymer has great effects on the viscosity of water-base UV varnish; the functional of monomer has great effects on the varnish performance, the viscosity, the volume shrinkage and curing rate is increasing but the glossiness is reducing with the increasing of the numbers of the functional groups; the value of pH of water-base UV varnish should be controlled the range of 8～9 to ensure the solubility of pre-polymer in water; the ratio of pre-polymer and monomer can be adjusted appropriately for the excellent performance of water-base UV varnish; the type and proportion of promoter has some effects on the performances of water-base UV varnish; the use of mixed monomers shows better performances compared with a single monomer; the water-base UV varnish is studied has excellent stability and weather-ability, the performances of adhesion, curing rate, viscosity, as well as glossiness meet the requirements of producing and can be coated on the machine.