Hot runner molding method of ultra-thin-wall polycarbonate products

Abstract

The invention relates to a molding technology of plastic parts, in particular to a hot runner molding method of ultra-thin-wall polycarbonate products. The invention is characterized in that the wall thickness of the applied ultra-thin wall polycarbonate products is 0.2mm; hot runners are adopted; the material temperature of instant high-speed and high-pressure material flow injected by a high-speed plastic molding machine is enhanced above the degradation temperature of the material flow to enhance the flowability of the material flow; and external cooling is adopted in mold opening, i.e. a blowing device is added on a mould and blows the products as soon as the mould is opened, therefore, a molding period is shortened and the high-temperature material flow is prevented from being degraded after staying in a hot nozzle for a long time. In the invention, the hot runners are successfully applied to the thin-wall mould, the material temperature is enhanced above the degradation temperature of the material by utilizing the hot nozzle; the external cooling method is adopted to shorten the molding period so as to control the staying time of the melting material in the hot nozzle and avoid degradation; the flowability of the melting material can be enhanced to be convenient to filling; and the external cooling method is simultaneously adopted for shortening the cooling time of the products so as to shorten the whole molding period.

Description

technical field [0001] The invention relates to a molding process of plastic parts, in particular to a hot runner molding method for ultra-thin-wall polycarbonate products. Background technique [0002] Usually the so-called thin-walled mold in injection molding generally has a thickness of about 0.3mm or even 0.5mm. When the thickness of the mold is thinner, such as the rare one with a thickness of 0.2mm, the difficulty of injection molding increases exponentially. At this time, according to the conventional thin-walled mold design, under normal molding conditions, the material temperature and fluidity of the PC material flow are insufficient, making it difficult to fill the material flow and meet the molding requirements of the product. [0003] Thin-walled molds require a high-speed molding machine to form, and the injection is instantaneous at high speed and high pressure. Generally, the hot runner cannot withstand such a large pressure, and it is easy to crack during m...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a hot runner molding method for ultra-thin-walled polycarbonate products according to the deficiencies of the above-mentioned prior art. The hot runner is used to increase the temperature of the material, enhance the fluidity of the material flow, and adopt external cooling to shorten the The product molding cycle can effectively solve the difficult problem of material flow filling and meet the product requirements