Blown tubing method and apparatus
US4624823A · kind A · utility
18Cited by
3References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 29, 1984 |
| Grant date | Nov 25, 1986 |
| Priority date | — |
| Expiry date | Jun 29, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/912
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Apparatus for cooling plastic film or sheet obtained by blowing tubing, comprising at its intermediate section an intensive blowing ring for directing air towards the tubing and at its upper section an upper chamber in which the tubing is in contact with an air flow directed in the drawing direction of the tubing. At the lower section of the apparatus is a non-closed lower chamber provided with at least one opening. The apparatus can be used to form blown films having superior optical properties, particularly clarity and turbidity, from a large number of resins.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.