Water-based Acrylic Modified Polyurethane Is Used As The Study Of Light-curing Coatings

Nowadays, people pay more and more attention to UV/EB curing coating and water borne coating, as they are environment friendly coating systems. They are also main developing trend of coating industrial. The advantage of UV coating is:(1) Fast curing speed, high production efficiency; (2) Curing in ambient temperature; (3) energy saving (4) environment friendly; (5) excellent coating performance; (6) compact equipments, easy for maintenance.So UV/EB curing coating has already been widely used in wood coating, plastic coating, optical fiber, ink and adhesive market. Normally, non-reactive volatile organic component, reactive monomers and other multi-functional acrylate are used in UV coating formulation to adjust viscosity. But reactive monomers strongly irritate to skin, and are harmful to people's health. Furthermore, lots of reactive monomers'reaction conversion is not very high after UV curing, the rudimental monomers will influence long-term stability of cured coating, and these rudimental VOC components are extractable and toxic.Water borne coating is environment friendly, nonflammable, safe, low-VOC and not harmful to health. It can be adjusted viscosity by water to be applied by roller coater, but the performance of conventional water borne coating cannot be compared with solvent borne coating system. Water borne UV coating combine the advantage of above two environment friendly coating systems. It has the advantage of no-pollution, no-toxicity, no-irritant and safe for production. Water borne UV coating has outstanding performance, and rapid curing speed, covers all advantage of UV/EB curing coating described above. It has already become a main development of UV curing systemWater borne acrylate modified polyurethane, also named as water borne polyurethane acrylate, is most researched and has best properties among water borne UV system. The paper investigated basic properties of water borne polyurethane acrylates in the market. It was used as main resin to research formulation of water borne UV coating; we optimize formulation to get high performance coating to meet general requirements of existing wood coating.In the investigation of water borne polyurethane acrylate'basic properties, firstly, study products'coalescence and find the best condition of coalescence. Secondly, through the test of photo-initiator, find that Irgacure1173, Irgacure500 and Irgacue819DW have good compatibility with water borne polyurethane acrylate, the best content of photo-initiator is 2.5% in formulation. Thirdly, test properties of cured water borne polyurethane acrylate, such as hardness, solvent resistance, adhesion, impact resistance, gloss, yellowing and so on.Then research how to use water borne polyurethane in wood coating formulation, adjust formulation and receive a ideal performance. Fristly, through study and adjustment of wood coating primer's formulation, find that Ucecoat7177 show best performance not only in clear primer but also colored primer, both have good adhesion on oily wood which is very difficult to get adhesion, and excellent grain accentuation.Ucecoat7177 also has good stability with pigment. Secondly, in the adjustment of wood sealer layer, we find that Ucecoat7177 and Bayhydrol UV2348 can provide good filler wetting and dispersion, it fill up the open pore of wood and increase coating's abrasion resistance. Thirdly, Bayhydrol UV2689 can provide excellent hardness, abrasion resistance, solvent resistance and other properties that top coating required in both clear coating and colored coating system. Two kinds of photo-initiator---Irgacure500 and Irgacure819DW are used to meet the UV curing of colored coating system.