How to solve the silver pattern generated when plastic injection molding?
January 12, 2022
Silver streaks are also known as (mica marks), bubbles. Some parts of the surface of the injection molded parts have inconsistent finish and a silver surface.
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Possible causes:
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Recommended remedy:
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Injection molding machine
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A. The surface temperature of the melt is too high
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Reduce the temperature of the shooting cylinder
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B. The plastic stays in the shooting tank for too long
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Reduce total cycle time
Injection volume is too small for injection molding requirements
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C. The temperature of the melt is too low to make the mold filling time unstable.
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Increase the temperature of the shooting cylinder
Increase the nozzle temperature
Increase mold filling speed
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D. Insufficient injection pressure
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Increase injection pressure
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E. The temperature controller is not accurate, which makes the control different.
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Check that the temperature controller is accurate and controllable
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Mold
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A. The mold surface temperature is too low
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Increase mold temperature
Limit the speed at which coolant flows through the mold
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B. There are some unplasticized plastic cold materials on the injection molded parts.
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Increase the size of the cold pocket
Extend the end of the runner to form an additional plastic cold pocket using an electrically heated nozzle and nozzle sleeve
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C. The runners and gates are too small or too long, causing the plastic to condense during transport
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Increase runner diameter and gate depth if needed
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D. Excessive mold release agent on the mold surface
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Thoroughly clean the mold surface with white alcohol
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