Analysis on the causes of the color of injection products
The main reasons for the uneven color of injection molding products and the solutions are as follows:
(1) the colorant diffusion is bad, often appear near the gate pattern.
(2) or plastic colorant thermal stability is poor to stable parts of the color, must be strictly fixed production conditions, especially the temperature of the materials, and the quantity of material and production cycle.
(3) of crystalline plastics, try to make parts of each part of the cooling speed consistent. For parts of wall thickness difference, available colorant to masking color. For wall thickness more uniform parts to fixed good gentle mold temperature.
(4) parts of the shape and gate form, the location of the plastic filling situation has affected, so that parts of the production of color, if necessary, to be modified.

Analysis on the reasons of the color and luster defects of injection products
Under normal circumstances, with injection moulding surface gloss mainly by the type of plastic, colorant and mold surface finish decided. But often because of some other reasons caused by the product's surface colour and luster defects, surface dark defects. Cause this reason and solution analysis is as follows:
(1) die cavity surface finish, rust, mold venting.
(2) the mold gating system has the flaw, should increase the cold material well, increases the flow passage, the polishing mainstream Road, the runner and the gate.
(3) the temperature of the material and the mold temperature is low, when necessary, the local heating method can be used.
(4) the working pressure is too low, slow speed, injection time, insufficient pressure, resulting in poor compactness and make the surface dark.
(5) the plastic should be fully plastic, but to prevent the degradation of the material, the heat to be stable, cooling should be sufficient, especially thick wall.
(6) prevent cold materials from entering the parts, if necessary, switch to a self locking spring or reduce the temperature of the nozzle.
(7) the use of recycled plastic colorant or too much, poor quality, mixed with water or other impurities, the use of the lubricant quality is poor.
(8) the clamping force should be sufficient.