1: Determine the grinding resin system
According to years of experience of Kain Chemical, long-oil alkyd resin, amino resin, polyamide resin, aldehyde and ketone resin, low molecular weight hydroxypropyl resin, etc. Pigments have good wettability, while saturated polyester resin with high molecular weight, low hydroxyl value hydroxypropyl, thermoplastic acrylic resin, etc. have relatively poor wettability to pigments, and the same pigment will show different performance in different resin systems. The hue of organic pigments, carbon black and transparent iron oxide will be different in different resins, especially the diffuse hue. Therefore, when choosing a dispersant, in order to make the color accurate, it should be tested according to the resin system. The compatibility of dispersant and resin, the viscosity-reducing effect of dispersant in this system, the color development and storage stability of dispersant in this system.
2: Choose according to pigments
Pigments are divided into several categories, namely organic pigments, inorganic pigments and carbon black
If the same resin and a dispersant can disperse carbon black and phthalocyanine pigments well at the same time, then it will largely show in DPP red organic pigments Weak dispersing ability, conversely, if a dispersant shows good dispersing ability for DPP red and other organic pigments, then using it to disperse carbon black or phthalocyanine blue will cause color difference or poor viscosity reduction
This is likely to be caused by the strength of the hydrogen bond of the pigment itself, so it is difficult to use a single-structure dispersant to obtain a large amount of pigments in two different systems. The effect is good. When actually choosing a dispersant, it should be considered comprehensively according to the parameters given by the pigment manufacturer. The most direct way is to apply it. However, as we continue to summarize the experience of application experiments, we will eventually avoid many detours. Welcome colleagues and friends to communicate .