Method of forming a multi-layer preform
US5049345A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 1989 |
| Grant date | Sep 17, 1991 |
| Priority date | — |
| Expiry date | Nov 9, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2949/3038
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An injection molded plastic preform for forming by blow molding a container such as a bottle. The preform is of a laminated construction and in the body area includes inner and outer layers of the same plastic and an intermediate layer of a different plastic. The bottom portion of the preform is provided with a core layer of still a third plastic with the injection temperature of the third layer being sufficient to erode the contacted part of the intermediate layer which is of a lower melt temperature. The third plastic may be the same plastic as the first plastic, but injected at a higher temperature. Generally speaking, the neck finish of the preform will be of a single layer of the first material, the body of the preform will be of a three ply construction which is also true of the bottom with there being an intermediate area of five ply where the bottom core layer projects into the lower portion of the intermediate layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.