In injection molding production, the gloss of plastic parts is mainly: mold, injection molding process, raw materials these three reasons. The following is a brief description of this issue, welcome to comment! 1. The mold cavity is badly processed, such as the mold cavity has scars, microholes, wear, roughness and other deficiencies, is bound to react to the plastic parts, so that the gloss of the plastic parts is poor, in this regard, to carefully process the mold, so that the surface of the cavity has a smaller roughness, if necessary, can be polished chrome plating. 2 cavity surface stains

such as cavity surface oil, water stains, or demoulding agent to make too much, will make the surface of the plastic parts dark, no luster, in this regard, to remove oil and water stains in time, and limit the use of demoulding agent.

3. The demoulding slope of the plastic parts is too small

demoulding slope is too small to cause demoulding difficulty, or the demoulding force is too large, so that the gloss of the surface of the plastic parts is the best, for this, to increase the demoulding slope.

4. Poor exhaust of the mold

If poor exhaust will cause too much gas to stay in the model, it will also lead to poor luster. In this regard, the exhaust system of the mold should be checked and corrected.

5. Improper gate or runner design

The cross section area of the gate or runner is too small or changes suddenly, and the melt flows in it under the shear force is too large, resulting in turbulent dynamic flow, resulting in poor luster. Therefore, the cross section area of the gate and runner should be appropriately increased.

two, injection process

1. Injection speed is too small

Injection speed is too small to cause the surface of the plastic parts is not dense, showing poor luster, which can be appropriately improved injection speed. 2. The cooling of plastic parts is not sufficient

If the cooling of thick wall plastic parts is not sufficient, the surface will be hairy and the luster is dark, in this regard, the cooling system should be improved. 3. Improper pressure holding operation

if the pressure holding pressure is too small and the pressure holding time is too short, the density of the plastic parts is not enough and the luster is poor, in this regard, the pressure holding pressure and pressure holding time should be increased.

4. If the melt temperature is too low

When the melt flow is too low, the fluidity is poor and the luster is easy to be poor. In this case, the melt temperature should be appropriately raised. 5. Uneven cooling of crystalline resin, such as PE, PP, POM and other plastic parts, such as uneven cooling will lead to poor luster, in this regard, the cooling system should be improved, so that the uniform cooling.

6. The injection speed and the gate area do not match

If the injection speed is too large and the gate cross-sectional area is too small, it will be dark and poor luster near the gate. In this regard, the injection speed can be appropriately reduced and the gate cross-sectional area can be increased.

3, raw materials

1. Raw materials with large particle size difference

size difference makes it difficult to evenly plasticize, and poor luster, in this regard, should be screened raw materials.

2. Too much secondary material in the raw material

If too much recycled material or spout material is added, it will affect the uniform plasticization of the melt and cause poor luster. In this regard, the amount of recycled material or spout material should be reduced.

3. Poor temperature resistance of raw materials

some raw materials will decompose and discolor in temperature regulation, resulting in poor luster. In this regard, raw materials with better temperature resistance should be selected.

4. Raw materials contain volatile material

if the content of moisture or volatile material in the raw material is too high, when heated, volatilized into gas, condensing in the cavity and melt, resulting in poor luster of plastic parts, in this regard, should be pre-dried raw materials.

5. The dispersity of additives is not good

some additives dispersity is too bad and the gloss of plastic parts is not good, in this regard, the additives with better flow performance should be used.

6. Raw materials are not pure

If raw materials are mixed with foreign bodies, miscellaneous materials or insoluble materials, they can not be evenly mixed and fused with their raw materials and lead to poor luster, in this regard, these miscellaneous materials should be strictly excluded in advance.

7. The amount of lubricant is too little

if the amount of lubricant is too little, the fluidity of the melt is poor, the surface of the plastic parts is not dense, which makes the luster poor, in this regard, the amount of lubricant should be appropriately increased.

Therefore, also according to your mold polishing degree to meet the requirements, if there is no problem with the mold itself, to determine the characteristics of your ABS to determine, you can choose high mold temperature, high speed and high pressure; Use chilled water to achieve a finish.