| 摘要 |
PURPOSE:To provide a urea resin molding material which can camouflage the presence of a filler, does not cause non-uniformity in color and is inexpensive, by blending decolored woodmeal as a filler. CONSTITUTION:A 2% aq. soln. of caustic soda is sprayed on, for example, the woodmeal of agathis wood, and then a 60% hydrogen peroxide soln. is sprayed thereon. The resulting woodmeal is heat-treated with steam at 100 deg.C to decolor it. The woodmeal is washed with hot water at 95 deg.C for 15min and dried to such an extent that the water content is reduced to 10% or below, to obtain decolored woodmeal. 20-80wt% (based on the combined quantity of woodmeal and resin) decolored woodmeal and a colorant (when the desired molding material is to be white, titanium oxide is used, while when it is to be colored, a pigment having the desired color is used) are mixed with a urea resin to obtain the desired urea resin molding material.
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