Masterbatch with pigment requirements

Masterbatch pigment used, must pay attention to the relationship with pigment and plastic raw materials, additives between points below their choice.

(A) pigment can not be reactive resins and various additives, solvent resistance, migration of small, good heat resistance and so on. That is, the masterbatch can not participate in a variety of chemical reactions. Such as carbon black can control the curing reaction of polyester plastic, so you can not add carbon black pigment in the polyester.

Due to the high temperature plastics molding, it should not break down color pigment in molding the heating temperature conditions. Inorganic pigments are generally better heat resistance, poor heat resistance of organic pigments and dyes, this point should be taken seriously enough variety in the choice of pigment.

(2) dispersion of the pigment should be of good color strength. When the toner dispersion non-uniform effect on the appearance properties of the products; coloring pigment is poor, toner will increase the amount of material costs. The same pigment dispersed in various resin and color strength are not the same, so when selecting the pigment in the attention to this point.

The particle size of the toner has a relationship with the dispersion, the smaller the toner particle diameter, the better the dispersibility, the coloring power is also strong.

(3) should be aware of pigment other properties, such as for use in food, children's toys aspects of plastic products, require the pigment should be non-toxic; used for electrical aspects of plastic products, electrical insulation should choose good pigment; plastic products for outdoor areas, you should choose a good resistance to weathering performance pigment and so on.

2 masterbatch production process

Masterbatch production process is very strict, generally use a wet process. Masterbatch material by grinding the aqueous phase, phase inversion, washing, drying, granulating, the only way to get the product quality assurance.

In addition, while the pigment grinding process, a series of tests should be carried out, such as the determination of the fineness of the sand slurry, the slurry was measured diffusion properties of sand, sand slurry solids content was measured and the measurement items fineness paste.

Masterbatch material production process, there are four methods:

(1) Ink method: As the name suggests, is the use of the production method of the ink paste masterbatch production, i.e., by a three-roll mill, the pigment surface coated with a layer of low molecular weight protective layer. After fine grinding paste and the carrier resin is mixed again, and then by two-roll mill (also called dual-roll mill) plasticized, and finally through a single screw or twin screw extruder granulation.

Its process is as follows:

Ingredients stirring thick paste three roll mill fine paste extrusion granulation two roll mill

(2) washing method: a pigment, water and dispersing agent by sanding, the pigment particles smaller than 1μm, and by phase-transfer method, the pigment into the oil phase, and then dried to obtain masterbatch. Need to use organic solvents, and solvent recovery during the corresponding phase inversion. The process is shown below:

Rinse the evaporator concentrate drying fine paste adding carrier extrusion granulation

(3) kneading method: after mixing the pigment and an oily carrier, a pigment lipophilic using this feature, by kneading the pigment flush from the aqueous phase into the oil phase. While the surface of the pigment coated with the oily carrier, the pigment dispersion stability and to prevent agglomeration of the pigments.

(4) Metal soap method: After grinding the pigment particle size of around 1μm, and the soap was added at a certain temperature, the surface layer of each pigment particle is uniformly wetted soap, forming a layer of a saponified solution, when a metal after saponification of the salt solution was added to the pigment surface layer of a chemical reaction with the metallic soap to produce a layer of the protective layer (magnesium stearate), so that the finely ground pigment particles will not cause flocculation, and a fine protection degrees.

Note 3 masterbatch used

(1) masterbatch store will absorb moisture over time, especially PET, ABS, PA, PC, etc., so according to the same qualities of grain drying process and reach moisture requirements.

(2) with the desired color masterbatch mixed colors must be very careful, and often change color and shade will occur.

(3) masterbatch and other additives will react, when used to attention.

(4) masterbatch dilution ratio selection should pay attention. Selection of high dilution ratio, the lower production costs, but also limited by the processing equipment.