In the plastic packaging industry, the plastic products in the same batch delivery, and some plastic products color yellow, very ugly, especially in the packaging for the final time, which greatly affect the product sales as well as beautiful, and therefore to the enterprise caused some losses. However, small plastic products that cause discoloration of the main reasons many of which have the following main points:
(1) The equipment is not clean. Dust or dirt on the device will allow plastic sheet contamination, this will cause discoloration of plastic.
(2) unbalanced thermocouple, temperature controller or temperature imbalances caused by heating systems, which would also make plastic packaging color.
(1) Mold vent is poor, resulting in plastic in high temperature and pressure conditions and oxygen vigorous reaction occurred, burn the plastic and so on.
(2) plastic sheet or that contained in the mold lubricant, release agent too, so we should be cleaned regularly, and then if that is to remove some of the anti-static additive of.
3, the sheet aspects.
(1) High water with volatile matter content.
(2) a colorant, additive decomposition temperature.
(3) the sheet is contaminated.