Color Masterbatch Color Requirements Non Woven Fiber,Non Woven Adhesive,Laminated Non Woven Fabric,Wet Laid Nonwoven Process Zhejiang Wangjin Nonwovens Co., Ltd , https://www.wangjinnonwoven.com
Color masterbatch pigment used, we must pay attention to color materials and plastic materials, additives, the matching relationship between the main points of choice are as follows.
(1) The colorant cannot react with the resin and various additives, and has strong solvent resistance, low migration, and good heat resistance. That is, the masterbatch cannot participate in various chemical reactions. For example, carbon black can control the curing reaction of polyester plastic, so carbon black cannot be added to polyester.
Due to the high temperature of molding and processing of plastic products, the colorants should not decompose and discolor under the conditions of forming and heating temperature. In general, inorganic pigments have good heat resistance, organic pigments and dyes have poor heat resistance, and this should be given enough attention when selecting pigment varieties.
(2) The dispersibility and coloring power of the pigment should be good. When the dispersion of the colorant is not uniform, the appearance performance of the product may be affected; when the coloring power of the colorant is poor, the amount of the colorant is increased and the material cost is increased. The dispersibility and coloring power of the same colorant in different resins are not the same, so this should be taken into account when selecting the colorant.
The particle size of the colorant is also related to the dispersibility. The smaller the particle size of the colorant, the better the dispersibility and the strong coloring power.
(3) should understand the other properties of pigments, such as for plastic products used in food, children's toys, the requirements of color materials should be non-toxic; for electrical products, plastic products, should choose good electrical insulation; For outdoor plastic products, pigments with good weathering resistance should be selected.
2. Masterbatch production process
Masterbatch production process is very strict, generally using wet process. The masterbatch is ground, phase-transformed, washed, dried and pelletized in the aqueous phase. Only the quality of the product can be guaranteed.
In addition, the pigments should be subjected to a series of tests, such as measuring the fineness of the sand-grinding slurry, measuring the diffusion performance of the sand-grinding slurry, determining the solid content of the sand-grinding slurry, and measuring the fineness of the colorant.
The masterbatch production process has four methods:
(1) Ink method: As the name implies, it is the production method of ink color paste in the production of masterbatch, that is, it is coated with a low molecular protective layer on the surface of the pigment through three-roll grinding. The ground fine paste is mixed with the carrier resin, then plasticized by a two-roll mill (also called a two-roll mill), and finally granulated by a single-screw or twin-screw extruder.
The process is as follows:
Ingredients Stirred Crude Pulp Three Rolls Fine Grinder Two-roll Mastic Extrusion Granulation
(2) Washing method: The pigment, water, and dispersant are sand-milled so that the pigment particles are less than 1 μm, and the pigment is transferred into the oil phase by a phase transfer method, and then dried to obtain a masterbatch. Organic solvents and corresponding solvent recovery devices are required for phase inversion. The process is as follows:
Thin paste rinse Evaporation concentrate dry Add carrier Extrusion granulation
(3) Kneading: After the pigment and the oil carrier are blended, the pigment is oleophilic and the pigment is washed from the aqueous phase into the oil phase by kneading. At the same time, the surface of the pigment is coated with an oil carrier to stably disperse the pigment and prevent aggregation of the pigment.
(4) Metal soap method: After the pigment has been grinded, the particle size reaches about 1 μm, and the soap is added at a certain temperature so that the surface layer of each pigment particle is evenly wetted by the soap liquid to form a layer of saponification solution. After the salt solution is added, it chemically reacts with the saponification layer on the surface of the pigment to form a protective layer of a metal soap (magnesium stearate), so that the finely pulverized pigment particles do not cause flocculation but protect a certain degree of fineness. degree.
3. The use of masterbatch precautions
(1) After the masterbatch is stored for a period of time, it will absorb moisture, especially PET, ABS, PA, PC, etc., so it should be dried according to the same process of the color particles and reach the water content requirement.
(2) Matching color masterbatch to achieve the desired color must be very careful, and often occur in color and shade changes.
(3) The masterbatch will react with other additives and be careful when using it.
(4) The selection of dilution ratio of masterbatch should pay attention. The use of a high dilution ratio results in lower production costs but is also limited by the processing equipment.