PARAPETTM is the trade name for the acrylic molding materials(PMMA),manufactured by KURARAY Co.,Ltd.
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TECHNICAL INFO
Molding conditions of "PARAPETTM"
It is difficult to determine precisely the molding conditions uniformly since they may fluctuate according to the type of machinery, machinery volume and the form of molding product, and structure of the metal mold. In general, please determine the optimal molding conditions setting the temperature of the cylinder and metal mold according to the following table.

Item G GF HR-L GR
Drying condition (°C)
Drying condition (time)
75-80
4-6
75-80
4-6
75-85
4-6
75-85
4-6
Mold temperature (°C) 40-60 40-60 50-80 50-80
Cylinder temperature (°C) 190-230 180-220 200-250 220-260
Injection pressure (MPa) 60-140 60-140 80-140 70-150

(1) Preparatory drying is essential because the methacrylic resin tends to absorb moisture. Molding pellets with moisture absorbed causes defects such as silver streaks, and flow marks.
(2) Mixture of foreign substances considerably disfigures the molded goods. Prevent dusts from entering the molding chamber, eliminate foreign substances at unpacking and clean inside and outside the machine.
(3) The GR grade may become milky when the molded goods has high humidity immediately after molding, but it will become transparent if it is cooled down to the room temperature. Too high injection speed may lower surface luster of the molded goods.