Plastic packaging products discoloration caused by several reasons
Plastic packaging products, the main advantage is to save raw materials, light weight, easy to transport, good sealing plastic case performance, comply with environmental green packaging packaging design requirements; able to wrap any special products, packing without additional cushioning material; being transparent plastic packaging packaging products visible , beautiful appearance, easy to sell, and are suitable for mechanization plastic trays and automation of packaging, ease of modern management, saving manpower and improve efficiency.
plastic box Plastic packaging products discoloration caused by the reasons are multi-faceted, there are:
1, raw materials
a. material contamination.
b. moisture and volatile matter content.
c. colorant additive decomposition.
2, equipment
a. equipment is not clean. Dust or other dust deposited in the hopper so that materials contaminated discoloration.
b. thermocouple, temperature controller thermostat or heating system disorders caused plastics products by failure.
c. the barrel obstructions, easy to packaging company promote degradation of plastics; cylinder or screw slot card with clear plastic box a metal plastic package foreign body, constantly grinding the plastic color.
d. nozzle hole, sprue and runner size is too small.
3, workmanship
a. barrel, nozzle temperature is too high.
b. screw speed is too high, pre-plastic backpressure too.
c. injection pressure is too high for too long, the injection speed is too fast to change products.
4, molds
a. mold gate too small.
b. dies bad exhaust, plastic is adiabatic compressed under heat and pressure react violently with oxygen, burn plastics.
c. compound or mold lubricants, mold release agents too. Periodically clean clamshell packaging the barrel if necessary, remove the heat resistance is even worse than the plastic antistatic additives.