Process for blow-molding and heat setting of polyester hollow formed body
US4913945A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 1988 |
| Grant date | Apr 3, 1990 |
| Priority date | — |
| Expiry date | Oct 13, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31786
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Disclosed is a process for the preparation of a heat-resistant polyester hollow formed body, which comprises mounting a preform of a thermoplastic polyester composed mainly of ethylene terephthalate units, which is maintained at a temperature where high-speed drawing is possible but whitening can be prevented, especially at a temperature represented by the following formula: EQU T=K(100.multidot.IV-8.multidot.DEG+42) (1) PA1 wherein IV stands for the intrinsic viscosity (dl/g) of the thermoplastic polyester, DEG stands for the content (% by weight) of diethylene glycol units in the thermoplastic polyester, k is a number of from 0.95 to 1.05, and T stands for the temperature (.degree.C.) of the preform, in a hollow forming mold maintained at a temperature as high as possible within the range where a final hollow formed body can be withdrawn without deformation substantially under non-cooling, blowing air maintained at a temperature higher than the preform temperature into the preform to effect stretch drawing and expansion drawing so that the drawing speed in the axial direction is at least 250%/sec and the drawing speed in the circumferential direction is at least 450%/sec, and eff…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.