Patent · US Expired

Method and an arrangement for the manufacture of a material web of foamed thermoplastics

US4261939A · kind A · utility

3Cited by

12References

22Claims

0Family size

Assignee

Tetra Pak International AB · SE

Inventors

Lennart Nilsson · Kungälv, SE
Sven Andren · Lund, SE
Per Ljungberg · Växjö, SE

Key dates

Filing date	Aug 8, 1979
Grant date	Apr 14, 1981
Priority date	—
Expiry date	Aug 8, 1999

Classification

Technology area (CPC B)Performing Operations; Transporting
CPC primaryB29L2023/00
WIPO fieldOther special machines
WIPO sectorMechanical engineering

Abstract

A method and apparatus are disclosed for the manufacture of a web of foamed thermoplastic material. The material web is extruded to form a tubular member and then expanded by action of a compressed fluid so that the outside of the tubular member is forced against a calibrating element arranged adjacent the tubular member. The tubular member is then cooled to a temperature below the softening temperature of the material and then is cut and converted into web form.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.