水性木器涂料涂装过程中的近红外干燥研究

Study on NIR Drying During Coating Process for Waterborne Wood Coatings

采用具有核壳结构的丙烯酸酯乳液分别配制了水性木器清底漆和清面漆,对比研究了涂装过程中近红外干燥和室温自然干燥两种方式对涂料样板性能的影响。结果表明:近红外干燥可以解决水性木器涂料在涂装过程中干燥速率慢的问题。底漆在70℃干燥4 min即可达到室温条件下干燥6 h达到的打磨性能,而面漆在70℃烘干6～8min得到的漆膜,其耐介质性、硬度和小分子的残余量等各项性能就可以达到室温自然干燥7 d的水平;延长干燥时间至10 min,得到的面漆各性能均良好,极大地提高了水性丙烯酸酯乳液涂料的干燥效率。

The water- borne primer varnish and topcoat were prepared with core -shell structure acrylate emulsion. The effect of drying methods by NIR and ambient drying in the coating process on properties of coating sample was investigated. It was indicated that the NIR drying can increase drying rate during the coating process of waterborne wood coatings, while that under ambient drying process was too slow. The waterborne primer without pigment dried under 70 ~C for 4 min by NIR, could achieve the same test result by ambinat drying 6 h for sanding. Moreover, chemical resistance, hardness, and amount of small molecule residual for the topcoat varnish could be obtained by NIR drying for 6 - 8 rain at 70℃ , which was similar to the topcoat varnish by ambient drying for 7 day. The properties of the topcoat varnish were excellent by NIR drying for 10 rain at 70℃. Therefore, NIR drying effectively speed up the drying process for the waterborne acrylate coatings.