Shanghai Daoqin Plastics Co., Ltd.

         generally product surface gloss defect can separation is below/following types: mold fault/failure, molding conditions control 不当, molding raw materials use 不当.

        一, mold fault/failure

         due to parts surface is mold type again 现, if mold surface has 伤痕, 腐蚀, micro and other surface defects, 就会复印 to parts surface generate gloss defect. type surface has 油污, water separation, demolding agent use amount more or selection 不当, make parts surface dark. therefore, mold type surface tool has relatively good light degree, most good 采取抛 light or surface 镀铬. type surface must maintain 清洁, and remove and water 渍. demolding agent product types and use amount need 适当.

         mold temperature degree for parts surface quality has very large effect/influence, usually, different types type plastics in different mold temperature conditions lower surface gloss relatively large, mold temperature high or low 都会导致 gloss defect. mold temperature low, material and mold type 腔接触 rear solid 化, make mold type again property decline. is increase gloss, can improve/increase mold temperature, most good is using/adopting in mold cooling in temperature water methods, make hot amount in type in speed 传递, 以免延 long molding cycle, this type of methods also can decrease/reduce molding in residual stress.

         in addition, demolding degree small, thick degree 突变, strip/profile thick and gate and 浇道截面太 small or 突然变化, system function large, material 呈湍流态 flow, mold gas defect and other mold fault/failure effect/influence parts surface quality, surface gloss defect.

        二, molding conditions control 不当

         if injection speed degree fast or slow, injection pressure low, holding pressure time short, increase pressure device pressure 不够, 缓冲垫 large, nozzle small or temperature degree low, fiber reinforcement plastics filler dispersion property can 太差, filler outer or aluminum filler direction property distribution, material temperature degree low, material defect and material 不足, 都会导致塑 parts surface gloss defect. for 此, for specific 情况进行 adjustment.

        若 in gate or 变截面处 generate dark 区, can through reduce injection speed rate, gate 位置, expand large gate 面积以 and in 变截面处 increase 圆弧 渡 and other to methods troubleshooting.

        若塑 parts surface has thin thin white, can reduce injection speed degree. if due to filler dispersion property can 太差导致 surface gloss defect, use flow property can relatively good resin or use mixing/compounding can force relatively strong/high screw.

        三, molding raw materials combined use requirements

         raw materials combined use requirements 也会导致塑 parts surface gloss defect. its generate causes and methods lower:

        1. molding raw materials in water separation or other easy material content high, molding 时挥发 formed separation in mold type and material shrink, 导致塑 parts surface gloss defect. for raw materials 进行预 drying 处理.

        2. raw materials or color agent separation understanding color gloss defect. selection resistant temperature relatively high raw materials and color agent.

        3. raw materials flow property can 太差, make parts surface 不密导致 gloss defect. use flow property can relatively good resin or increase use amount lubricant and improve/increase processing temperature degree.

        4. raw materials in mixed has material or versus solvent raw materials. use new material.

        5. raw materials degree non-uniform. remove 粒径差异太 large raw materials.

        6. crystallization type resin due to cooling 不均导致 gloss defect. combined control mold temperature and processing temperature degree, for/regarding thick parts, if cooling 不足, make parts surface 发毛, gloss dark, solution methods is will parts from mold in rear, 立即放入浸 in cold water in cold pressure in cooling type.

        7. raw materials in recycled material use ratio/proportion high, effect/influence material uniform 塑化. decrease/reduce its use amount.