UV thermal dual curing primer developed by Changzhou Institute for vacuum coating of automobile lamps
Recently, CNOOC Changzhou coating Chemical Research Institute Co., Ltd. has developed a UV heat dual curing primer for vacuum coating of vehicle lamps. The construction method of the coating is studied. The primer and construction method studied make the primer film have good adhesion and heat resistance on plastic substrate which is difficult to adhere.
With the development of automobile industry, the application of lightweight decorative materials is more and more widely, and automobile lighting parts is one of the main parts. The automobile lamp is mainly made of unsaturated polyester thermosetting plastics with different shapes. Then a layer of primer is coated on the surface of the plastic, and then the vacuum coating is carried out by using the vapor deposition method to form the optical mirror, which produces a good reflective effect. In the early stage, the primer used for vacuum coating was mainly two-component hot baking paint, but the optical mirror effect of the lamp after coating was not good, and the heat resistance was not ideal.
At present, many manufacturers begin to use UV curable coating. Due to its low viscosity and fast curing characteristics, the surface of the coating is smooth and the mirror effect of the coating is good. However, due to the defects of high internal stress and poor adhesion, it is difficult to give consideration to both adhesion and heat resistance of the coating film.
For this reason, CNOOC Changzhou coating Chemical Research Institute Co., Ltd. has developed a UV thermal dual curing primer for vacuum coating of vehicle lamps, which can give consideration to adhesion and heat resistance, and has good construction performance. In this study, a two-component system was adopted. Component a includes isocyanate modified acrylic resin containing carbon carbon double bond and hydroxyl group, oligomer containing carbon carbon carbon double bond and at least two The isocyanate modified acrylic resin containing carbon carbon double bond and hydroxyl group was prepared by condensation reaction of hydroxyl acrylic resin and single capped end adduct, which was synthesized by diisocyanate and hydroxyl containing (meth) acrylate monomer. Component B uses multifunctional isocyanate curing agent.
In addition, CNOOC Changzhou coating chemical research institute also studied the application method of the coating. Firstly, the plastic molded parts of automobile lamps were pretreated; secondly, the component A and component B of the UV thermal dual curing primer were mixed evenly and used within 1 hour at room temperature; the primer was applied for 1-2 times, pre baked at 50-kktc for 3-15 minutes, and then irradiated with ultraviolet light source After curing at 60-120 ℃ for 1-3 h, the final dry film thickness is 10-30 μ m, and then the vacuum coating can be carried out.
In 2014, China, as the world's largest automobile market, accounted for 25% of the global market, of which passenger cars accounted for a higher share of the global market, reaching 30%. "The 12th Five Year Plan" promotes the rapid development of automobiles, but at the same time, it inevitably brings environmental problems "haze". Energy saving and emission reduction and cleaner production have been taken action in automobile manufacturing industry. Painting workshop is a major energy consumption and pollution source of automobile, engineering machinery and rail transit vehicle manufacturing industry, and is the target of environmental friendly and low-carbon economic society.