(1) If the mold cavity is poorly processed, if there are defects such as scratches, micropores, abrasion, roughness, etc., it will inevitably be reflected on the plastic parts, so that the gloss of the plastic parts is poor. In this case, the mold must be carefully processed so that the cavity surface has Smaller roughness, if necessary, can be polished with chrome.
(2) If the surface of the cavity is oily or watery, or if the release agent is too much, the surface of the plastic part will be dark and dull. To do this, remove the oil and water stains in time, and use the release agent in a limited amount.
(3) If the mold release angle is too small, the mold release is difficult, or the force is too large when the mold is released, so that the surface of the plastic part is good, and the draft angle is increased.
(4) If the mold is poorly exhausted, too much gas stays in the mold, which also leads to poor gloss. In this case, the mold exhaust system should be inspected and corrected.
(5) If the cross-sectional area of the gate or flow passage is too small or abruptly changed, the shear force is too large when the melt flows therein, and the turbulent flow is dynamic, resulting in poor gloss. In this case, the gate and runner cross-sectional area should be appropriately increased.