水性单涂层工艺汽车面漆外观影响因素的研究

Study on the Factors Affecting the Appearance of Waterborne Monocoat Used as Automobile Topcoat

建立以黏度、膜厚、流平时间、旋杯转速、底材粗糙度、助剂和溶剂等分别为单一变量的实验设计方法,研究了水性单涂层白实色面漆外观的影响因素。结果表明,高黏度35s.50μm以上的膜厚、7min以上的流平时间、旋杯转速40kr/min、添加二乙二醇丁醚和流平剂BYK-345以及底材粗糙度Ra为0.145μm时,漆膜的LW最小,SW最小,DOI值最高,外观最佳,但需防止漆膜流挂弊病的发生。结合现场实际以及成本要求,水性单涂层汽车面漆采用中等黏度的喷涂黏度、适当的膜厚、7min左右的流平时间,45kr/min左右的旋杯转速,添加高沸点溶剂和流平剂以及选用粗糙度Ra相对较低的电泳底材,可得到好的外观表现。

An experimental design method with viscosity,film thickness,leveling time,rotating speed of bell,roughness of substrate,additives and solvent as single variables was established to study the factors affecting the appearance of waterborne white solid color topcoat.The results showed that the LW and SW value of coatings was the lowest,the DOI value was the highest,and the appearance was the best with the viscosity of 35s,the film thickness of more than 50μm,the leveling time of more than 7 min,the bell rotating speed of 40 krpm,the substrate roughness Ra of 0.145μm and incorporation of diethylene glycol butyl ether and BY K-345 as solvent and leveling agent,respectively.But it is necessary to prevent the sagging defects of film.According to actual application situation and cost requirements,the waterborne monocoat used as automobile topcoat provides good appearance by adopting medium spray viscosity,appropriate film thickness,leveling time of 7 min,bell rotary speed of 45 krpm,incorporation of high boiling point solvents and leveling agent,and using electrophoretic substrate with relatively low roughness.