Auxiliaries are auxiliary components of UV coatings. The role of additives is to improve the coating’s processing performance, storage performance and construction performance, improve the film performance and give some special functions. UV coatings commonly used additives are defoaming agent, leveling agent, wetting dispersant, adhesion promoter, extinction agent, polymerization inhibitor, etc., they play a different role in UV coatings.
(1) The addition of antifoaming agent and antifoaming agent can avoid the formation of soak, while the addition of antifoaming agent can eliminate the formed foam. Because the surface tension of defoaming agent is low, especially the surface tension of defoaming agent with strong defoaming effect is lower, so the amount of addition should be in order to solve the foam, excessive addition, easy to cause shrinkage cavity. In recent years appeared the defoaming agent that contains fluorine again, defoaming effect is good, dosage is very little also.
(2) after the construction of leveling agent coating, there is a flow and dry film forming process. The degree to which the wet film can flow and eliminate marks after application, and the film can be even and flat after drying, is called leveling.
(3) wetting dispersant wetting agent, dispersant is to improve the efficiency of paint grinding, to maintain the stability of the dispersion system necessary for a class of additives. Wetting agent and dispersant have low surface tension and good compatibility with resin system. The wetting dispersants used in UV coatings are mainly polymers containing pigments and groups.
(4) adhesion promoter adhesion promoter is a kind of additive can improve the adhesion between the coating and the substrate, for some coating is difficult to adhere to the substrate such as metal, plastic, glass, etc., in the coating often add human adhesion promoter.
(5) the gloss of the extinction agent is an important property of the coating after film formation. To produce low gloss or matt coating, it is necessary to add extinction agent in the coating to achieve. Extinction agent refractive index as close as possible to the refractive index of resin (1.40 ~ 1.60), so that the preparation of extinction coating transparency is good, also does not affect the color of the paint.
(6) polymer inhibitor this is used for UV coating in the production, transportation and storage to avoid thermal polymerization, improve the storage stability of UV coating and add additives. They must be in the presence of oxygen to produce polymerization resistance, so UV coating storage containers, must set aside enough air to ensure that there is enough oxygen.
Post time: Apr-12-2022
