How to increase the brightness of ABS injection molded parts? -- DGMF Mold Clamps Co., Ltd

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DGMF Mold Clamps Co., Ltd
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How to increase the brightness of ABS injection molded parts?
Written by Jasmine HL
First, injection mold
1. Poor mold cavity processing
If the mold cavity has scars, micropores, wear, roughness, etc., it will inevitably reflect on the
plastic part, making the plastic part poor in gloss. In this regard, it is necessary to carefully
process the mold to make the surface of the cavity have a smaller roughness. Polished when
polished.
2.Stain on the cavity surface
If the surface of the cavity has oil stains, water stains, or too much release agent, the surface of
the plastic part will be dark and dull. In this regard, it is necessary to remove oil stains and water
stains in a timely manner and limit the use of mold release agents.
3. The mold release slope of the plastic part is too small
The too small demolding angle will cause difficulty in demolding, or excessive force during
demolding will make the surface of the plastic part have the best gloss. In this regard, the
demolding angle should be increased.
4. Poor mold venting
If the exhaust gas is not good, it will cause too much gas to stay in the mold, and it will also cause
poor gloss. Therefore, check and correct the mold exhaust system.
5.Improper gate or runner design
The cross-sectional area of the gate or runner is too small or changes abruptly. When the melt
flows through it, the shear force is too large, and the turbulent dynamic flow results in poor gloss.
Therefore, the cross-sectional area of the gate and runner should be appropriately increased.
Second, the injection molding process

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DGMF Mold Clamps Co., Ltd
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1. Injection speed is too small
If the injection speed is too small, the surface of the plastic part is not dense and the gloss is poor.
For this reason, the injection speed can be appropriately increased.
2.Insufficient cooling of plastic parts
If the cooling of thick-walled plastic parts is inadequate, the surface will become fluffy and the
gloss will be dark. For this reason, the cooling system should be improved.
3. Improper pressure holding operation
If the holding pressure is too small and the holding time is too short, the density of the plastic
part is insufficient and the gloss is poor. In this regard, the holding pressure and 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 gloss is easily caused. Therefore, the
melt temperature should be appropriately increased.
5. Uneven cooling of the crystalline resin
For example, plastic parts made of PE, PP, POM, etc., if the cooling is not uniform, it will cause
poor gloss. Therefore, the cooling system should be improved to uniformly cool.
6. Injection speed does not match gate area
If the injection speed is too large and the cross-sectional area of the gate is too small, the vicinity
of the gate will be dark and poor in gloss. For this reason, the injection speed and the
cross-sectional area of the gate can be appropriately reduced.
Third, raw materials
1. The large difference in raw material particle size
The large particle size makes it difficult to plasticize uniformly, but the gloss is poor. Therefore,
raw materials should be sieved.
2. Too many secondary materials in the raw material
If too much-recycled material or nozzle material is added, it will affect the uniform plasticization
of the melt and cause poor gloss. For this reason, the amount of recycled material or nozzle
material should be reduced.
3. Poor temperature resistance of raw materials
Some raw materials will decompose and discolor during temperature adjustment, resulting in
poor gloss. Therefore, raw materials with better temperature resistance should be selected.
4. Raw materials contain volatiles
If the moisture or volatile matter content in the raw material is too high, it will volatilize into gas
when heated and will condense in the cavity and the melt, resulting in the poor gloss of the
plastic part. Therefore, the raw material should be pre-dried.
5. Poor dispersion of additives
Some additives have poor dispersibility and poor plastic gloss. Therefore, additives with better
flow properties should be used instead.
6. Impure raw materials
If foreign materials, miscellaneous materials or immiscible materials are mixed in the raw
materials, they cannot be evenly mixed with their raw materials to cause poor gloss. Therefore,

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these miscellaneous materials should be strictly excluded in advance.
7. Too little lubricant
If the amount of lubricant is too small, the melt fluidity is poor, the surface of the plastic part is
not dense, making the gloss poor, for this reason, the amount of lubricant should be
appropriately increased.
Therefore, it is also necessary to determine whether the polishing degree of your mold meets the
requirements. If there is no problem with the mold itself, you must determine the characteristics
of your ABS. You can choose high mold temperature, high speed, and high pressure; you can also
use chilled water to achieve smoothness.