橡椀单宁铁离子能形成深兰色的络盐,经氧化以后,外观以黑色呈现出来,能吸附在纤维上。利用此特性,可应用于麻袋包装印商标。我地区印刷厂原来印商标是用快色素,据介绍是进口的,每公斤价格为70元,后来因快色素在市场上奇缺,有关单位希望我厂能协助解决,于是我们同印刷厂一起搞试验,以橡椀栲胶为原料试制黑色素代替进口快色素??974年8月起麻袋印商标一直是使用橡椀栲胶黑色素,其方法如下: 1公斤橡椀栲胶用5公斤蒸馏水加热溶解,再加20克亚硫酸钠,在90℃磺化1个小 Rubber tannin iron ions can form a dark blue complex salt, after oxidation, the appearance of a black appearance, can be adsorbed on the fiber. Use of this feature can be applied to sacks packaging and printing trademarks. I printed the original printing area in the region is the use of fast-color printing ink, according to the introduction is imported, the price per kilogram 70 yuan, and later because of the rapid shortage of pigment in the market, the relevant units hope that I can help solve the plant, so we together with the printing plant Engage in trials, the rubber bowls of plastic raw materials for the trial production of melanin instead of imported fast-color pigment?? In August 974 Sacks printed trademark has been the use of rubber bowel gum melanin, the method is as follows: 1 kg of rubber rubber gum with 5 kg of distilled water heating Dissolved, plus 20 grams of sodium sulfite, sulfonated at 90 ℃ 1 small