Dispersant is a commonly used auxiliary agent in toner, which helps to wet the pigment, reduce the particle size of the pigment, and increase the affinity between the resin and the pigment, thereby improving the compatibility between the pigment and the carrier resin, and improving the dispersion of the pigment. Level. In the process of color matching, different types of dispersants will affect the color quality of the product.
The melting point of the dispersant is generally lower than the processing temperature of the resin, and during the molding process, it melts before the resin, thereby increasing the fluidity of the resin. And because the dispersant has low viscosity and good compatibility with pigments, it can enter into the pigment agglomerate, transfer external shear force to open the pigment agglomerate, and obtain a uniform dispersion effect.
However, if the molecular weight of the dispersant is too low and the melting point is too low, the viscosity of the system will be greatly reduced, and the external shear force transferred from the sample to the pigment agglomerates will also be greatly reduced, making it difficult to open the agglomerated particles and the pigment particles cannot be well dispersed. In the melt, the color quality of the product is ultimately unsatisfactory. When using dispersants in the color matching process, parameters such as relative molecular weight and melting point must be considered, and dispersants suitable for pigments and carrier resins should be selected. In addition, if the amount of dispersant is too large, it will also cause the color of the product to turn yellow and cause chromatic aberration.
References
[1] Zhong Shuheng. Color Composition. Beijing: China Art Publishing House, 1994.
[2] Song Zhuoyi et al. Plastic raw materials and additives. Beijing: Science and Technology Literature Publishing House, 2006.
[3] Wu Lifeng et al. Masterbatch User Manual. Beijing: Chemical Industry Press, 2011.
[4] Yu Wenjie et al. Plastic Additives and Formulation Design Technology. 3rd Edition. Beijing: Chemical Industry Press, 2010.
[5] Wu Lifeng. Design of plastic coloring formula. 2nd edition. Beijing: Chemical Industry Press, 2009
Post time: Jul-09-2022