How can ABS injection molded parts increase brightness

The main reasons for poor gloss of plastic parts are: mold, injection molding process, raw materials and so on.

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1. If the mold cavity is poorly processed, such as scars, micropores, wear, roughness and other deficiencies, it is bound to be reflected on the plastic parts and make the plastic parts have poor luster. For this, the mold should be carefully processed to make the surface of the cavity have small roughness, and chrome plating can be polished if necessary.

2. If there are oil and water stains on the surface of the cavity, or too much release agent will make the surface of the plastic part dark and dull. For this, remove the oil and water stains in time and use the release agent.

3. If the demoulding slope of the plastic part is too small, it is difficult to demould, or the force is too large during demoulding, which makes the surface luster of the plastic part good, increase the demoulding slope.

4. If the mold exhaust is poor and too much gas stays in the model, it will also lead to poor gloss. For this, check and correct the mold exhaust system.

5. If the cross-sectional area of the gate or runner is too small or changes suddenly, and the melt flows in a turbulent dynamic flow due to too large shear force, resulting in poor gloss, the cross-sectional area of the gate and runner shall be increased appropriately.

2、 Injection molding process

1. If the injection speed is too small, the surface of plastic parts is not dense and shows poor gloss, the injection speed can be appropriately increased.

2. For thick wall plastic parts, if the cooling is not sufficient, the surface will be hairy and the luster will be dark. For this, the cooling system should be improved.

3. If the holding pressure is insufficient and the holding time is too short, resulting in insufficient density and poor gloss of plastic parts, the holding pressure and holding time shall be increased.

4. If the melt temperature is too low, resulting in poor fluidity and poor gloss, the melt temperature shall be appropriately increased.

5. For plastic parts made of crystalline resin, such as PE, PP, POM, etc., uneven cooling will lead to poor gloss. Therefore, the cooling system should be improved to make it cool evenly.

6. If the injection speed is too high and the gate cross-sectional area is too small, it will be dark and poor gloss near the pouring product. Therefore, the injection speed can be reduced and the gate cross-sectional area can be increased appropriately.

3、 Raw materials

1. Due to the large particle size difference of raw materials, it is difficult to plasticize uniformly and the luster is poor. Therefore, the raw materials should be screened.

2. Too much recycled material or nozzle material is added in the raw material, which affects the uniform plasticization of the melt and has poor luster. Therefore, the amount of recycled material or nozzle material should be reduced.

3. Some raw materials will decompose and change color during temperature regulation, resulting in poor gloss. Therefore, raw materials with good temperature resistance should be selected.

4. The content of water or volatile matter in raw materials is too high, which volatilizes into gas when heated and condenses in the mold cavity and melt, resulting in poor gloss of plastic parts. For this, the raw materials shall be pre dried.

5. Some additives have poor dispersibility and poor luster of plastic parts. Therefore, additives with good flow performance should be used.

6. The raw materials are mixed with foreign matters, impurities or immiscible materials, which cannot be evenly mixed with their raw materials, resulting in poor gloss. For this, these impurities shall be strictly excluded in advance.

If the amount of lubricant is too small, the fluidity of the melt is poor, and the surface of the plastic part is not dense, resulting in poor gloss, the amount of lubricant should be increased appropriately.