Low gloss means that the surface is dark and dull, and the transparency of transparent products is low. There are many reasons for poor gloss. The surface gloss defects of general products can be divided into the following three types: plastic mold failure, improper molding conditions, improper use of raw materials.
Injection mold failure
Because the surface of the plastic part is the reproduction of the surface of the mold cavity of the plastic mold, if the surface of the plastic mold has scratches, corrosion, micropores and other defects, it will be copied on the surface of the plastic parts, producing bad luster. If the surface of the cavity is oily and moist, the surface of the plastic part will be dark. Therefore, the cavity surface of plastic mould should have good finish. The surface of die cavity must be kept clean and oil and water stains should be removed in time. The type and amount of release agent should be appropriate.
The temperature of plastic mold also has a great influence on the surface quality of plastic parts. Generally, different types of plastics have different surface gloss under different temperature conditions, and the injection mold temperature cannot be too high or too low, which may lead to poor gloss.
In addition, the plastic mold demoulding slope is too small, the section thickness is abrupt, the rib is too thick, the gate and runner section are too small, the shear effect of gating system is too large, and the plastic mold exhaust is poor, etc., all of these will affect the surface quality of plastic parts, resulting in poor surface gloss.
Improper use of raw materials
Raw materials not meeting the requirements will also lead to poor surface gloss of plastic parts.
Cause: the moisture content in the molding material is too high, and the volatile components condense in the cavity wall of the plastic mold and in the molding process, resulting in poor surface gloss of plastic parts. Treatment: raw materials should be dried in advance.
Discoloration of raw materials or colorants results in poor gloss. High temperature resistant materials and colorants should be used.
The fluidity of raw materials is too poor, and the surface of plastic parts is not compact and glossy. Change the resin with better fluidity or add proper amount of lubricant and increase the processing temperature.
If the magazine is mixed with raw materials, new materials shall be replaced in time.
Improper molding conditions
If the injection speed is too fast or too slow, the injection pressure is too low, the holding time is too short, the supercharger pressure is not enough, the nozzle hole is too small or the temperature is too low, the dispersion of fiber reinforced plastics is too poor, the cylinder temperature is too low, the melt plasticization is not good, and the supply is insufficient, all these conditions can lead to poor surface gloss of plastic parts. For the causes should be specific analysis of the specific reasons, and then make corresponding adjustments.
About JasonMould Industrial Company Limited
Jasonmould is a China mold maker of plastic molds- injection mold, die casting moulds, plastic blow molding, rotational molding, medical plastic injection molding, two shot plastic injection molding, insert molding, overmolding, metal injection molding, micro injection molding, powder injection molding, ceramic injection molding, liquid injection molding, husky injection molding, household mold, casting mold, die mold tool, custom molds, china moulds, rapid prototyping tooling, plastic prototyping tooling, punch press tooling, die and tooling for mobile/ cell phone parts, automotive parts, vacuum cleaners, rechargeable tools, telephones, copiers, computers, multimedia speakers, and many other electronic products and household appliances. And also a plastic product manufacturer, mold manufacturer China– plastic parts, plastic water tank, plastic balls, plastic containers, plastic buckle, plastic anchor, plastic hanger, plastic spoon, plastic pipe fitting, plastic tumble, plastic tableware, plastic cups, plastic bottles, plastic tray, plastic cosmetic container, plastic case, plastic food container, plastic chairs, plastic caps, plastic cap closure, plastic tubes, plastic water pipes, plastic knobs, plastic tubing, plastic utility boxes, plastic racks and so on.
Contact:
Person: James Yuan
Company: JasonMould Industrial Company Limited
Add: LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong Province, China
Tel: 86-752-6682869
Email: [email protected]
Site: https://www.jasonmolding.com/custom-injection-molding/
