| 摘要 |
PURPOSE:To obtain a high-quality colorant for synthetic resins, wherein a pigment having a fine particle size is efficiently dispersed, by adding PE or wax to a pigment each contg. a polyhydric alcohol and feeding the mixture to an extruder. CONSTITUTION:15-40pts.wt. polyethylene having a melt index of 30-100 and/or wax having a melting temp. of 85-110 deg.C are/is mixed with 100pts.wt. pigment cake obtd. by a mixing 60-90wt% pigment powder, 20-50wt% polyhydric alcohol (or derivative)well-affinitive with water and having a b.p. of 120-200 deg.C and 60-90wt% water contg. an alkali component so as to give a pH of 6.5-7.5 and shaping the mixture into a cake, thus preparing a raw mixture. The mixture is fed through a feed opening of a twin-screw extruder to the extruder having a chamber provided with a feed opening at one end, a discharge port at the other end and at least two steam discharging ports therebetween and having twin-screw blade rotors provided in parallel within the chamber. The mixture is kneaded and deaerated, and a dry product is discharged through the discharge port. |
