速生杨木材染色处理工艺的研究

Study on dyeing treatment technology of fast-growing poplar wood

针对当前采用杨木单板为基材进行材色改良,处理过程中单板破损率高,后续加工复杂的现状,选用3种具有代表性的染料:酸性大红GR,活性黄K-RN,直接深棕B-NM,对杨木厚木(30 mm)进行染色处理。选取染色温度、染色时间、促染剂Na2SO4添加量和改性剂胺溶铜季铵盐添加量4个因素3个水平进行正交试验。利用环境扫描电镜观察染料在木材内部的分布状态。用90℃的皂液处理染色后试件30 min后,测皂洗前后色差值,利用色差值变化评价其皂洗牢度。试验结果确定最优染色工艺条件:染色温度80℃,时间9 h,促染剂Na2SO440 g/L,改性剂5 g/L。其中改性剂添加量对试件染色效果的影响最大,其次是染色温度和染色时间。酸性染料分布木材的导管腔内,活性染料存在木纤维细胞壁中,直接染料很难渗透到木材内部。皂洗结果确定活性染料抗流失性最好。在最优工艺条件下染色深度30 mm,染透率100%,皂洗前后色差值9.98。

In view of the present situation that dyeing industry uses poplar veneer as base material to modify the color, having high breakage rate of the veneer, and complex subsequent processing. Three representative dyes （acid red GR, active yellow K-RN, direct deep brown B-NM）, were seleeted to dye the specimen with 30 mm thick. In aspects of dyeing temperature, dyeing time, accelerating agentdosage and modifier quaternary ammonium salt. Four factors of three levels for orthogonal tests were carried out. The dyestuff distribution in the poplar wood was observed by using SEM. Measured the color difference of dyed specimen was after treated with liquid soap process 30 mm under 90 ℃ . The soaping fastness of the dyed specimen was evaluated by using color differences before and after the liquid soapmeasures. Test results show the optimal dyeing process conditions： dyeing temperature 80 ℃, time 9 h, the accelerating agent NazSO440 g/ L, modifier 5 g/L. And modifier dosage had the greatest impact on the dye depth of poplar specimen, followed by dyeing temperature and time. SEM shows that acid dyes were observed in the catheter, reactive dyes were observed in the cell wall of wood fiber. It was very hardfor direct dyes to permeate through the wood. Soaping test shows that the specimen dyed with reactive yellow K-RN had the best resistance leach ability. In the optimal dyeing technology conditions, the dyeing depth up to 30 ram0 penetration ratio achieved 100%, soaping color difference was 9.98.