Manufacture of expanded plastic sheet

Abstract

Abstract PURPOSE:To obtain the captioned expanded sheet having no longitudinal wrinkle but a smooth surface and useful for a sheet packing or the like by a method wherein a forming plate having a cooling capacity is provided near a flat die at the tip end of an extruder to contact all over the surface of the form. CONSTITUTION:In a manufacturing method of the expanded plastic sheet wherein the flat die is employed at the tip end of the extruder, a pair of upper and lower forming plates 3, 3' having a cooling capacity are provided neighboring the flat die 1 interposing heat insulating plates 2, 2' between the die 1. A molten resin 41 containing an expanding agent is supplied to the flat die 1 from the extruder and is released from the opening part of the flat die 1 into the open air to form the expandable plastic sheet 42 while all over the surface of this sheet is contacted with the forming plates 3, 3', thereby obtaining the objective expanded sheet.

Inventors

• 👤 Takeshi Aragai
• 👤 Takashi Nagai
• 👤 Sadahito Kobori

Bibliographic Details