The color material used in the color masterbatch, the color masterbatch technology must pay attention to the matching relationship between the color material and the plastic raw materials and additives. The selection points are as follows.

1. The pigment cannot react with resin and various additives, and has strong solvent resistance, small migration, and good heat resistance.

That is to say, the masterbatch cannot participate in various chemical reactions. For example, carbon black can control the curing reaction of polyester plastic, so carbon black material cannot be added to polyester.

Because of the high molding temperature of plastic products, the color masterbatch technology should not decompose and discolor under the molding heating temperature.

Generally, inorganic pigments have good heat resistance, while organic pigments and dyes have poor heat resistance, which should be paid attention to when selecting colorants.

2. The dispersibility and tinting strength of the pigment should be good.

When the colorant is not uniformly dispersed, it will affect the appearance of the product; when the colorant has poor tinting strength, the amount of the colorant will increase and the material cost will increase. The dispersibility and color strength of the same colorant in different resins are not exactly the same, so you should pay attention to this when selecting the colorant. The particle size of the pigment is also related to the dispersibility. The smaller the particle size of the pigment, the better the dispersibility and the stronger the tinting strength. The technical requirements of color masterbatch are very strict, and the generally adopted color masterbatch technology is wet process. The color masterbatch is made by water phase grinding, phase inversion, water washing, drying and granulation. Only in this way can the product quality be guaranteed.

There are four methods for the technical process of color masterbatch

(1) Color masterbatch technology process ink method: As the name implies, it is a production method of ink color paste in the production of color masterbatch, that is, through three-roller grinding, a low molecular protective layer is coated on the surface of the pigment. The ground fine paste is mixed with the carrier resin, then plasticized by a two-roll plasticizer (also called a two-roll open mill), and finally granulated by a single-screw or twin-screw extruder.

(2) Rinse method of color masterbatch technology: The pigment, water and dispersant are sanded to make the pigment particle smaller than 1 μm, and the pigment is transferred into the oil phase by the phase transfer method, and then dried to obtain the color masterbatch. An organic solvent and a corresponding solvent recovery device are required for phase inversion.

(3) Kneading method of color masterbatch technology: After mixing the pigment with the oily carrier, the pigment is washed from the water phase into the oil phase by kneading by using the lipophilic feature of the pigment. At the same time, the surface of the pigment is coated by an oily carrier to stabilize the dispersion of the pigment and prevent the pigment from coagulating.

(4) Metal soap method of color masterbatch technology: After the pigment is ground, the particle size reaches about 1 μm, and soap liquid is added at a certain temperature, so that the surface layer of each pigment particle is evenly wetted by the soap liquid, forming a layer of Saponification solution, when the metal salt solution is added, the saponification layer on the surface of the pigment reacts chemically to form a protective layer of metal soap (magnesium stearate), so that the finely ground pigment particles will not cause flocculation, and Protect a certain fineness.