Abstract:In order to improve the effect of color fixation on paper, the cationic starch was added in paper dyeing process. In this paper, the mechanism of color fixation on paper surface by cationic starch, the effects of substitution degrees with different cationic starchs and the most optimal fixation technique were studied. Single factor experiments, such as the effects of cationic starch substitution degree, dosage of cationic starch, dye solution pH value and temperature on color fixation efficiency were carried out. It was inferred by optical microscope and SEM observation that due to the close attraction of the negatively charged edible pigments and the positively charged cationic starch. In turn the cationic starch which carries the edible pigment was closely combined with the negatively charged fibers, making the color was fixed on paper. The experiment showed that the higher substitution degree of cationic starch was, the better fixing effect would be. What’s more, the best conditions for color fixation were found as follows: pH value 6, temperature was 80℃, cationic starch dosage was 1.5%, the color fixation effect upgraded 84.4% compared with the blank group. |