Multilayer structures having annular profiles and methods and apparatus of making the same
US8562885B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 2010 |
| Grant date | Oct 22, 2013 |
| Priority date | — |
| Expiry date | Oct 7, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1393
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Disclosed are multilayer film structures having annular profiles, and methods and apparatus of making the structures disclosed. The annular multilayer articles have a uniform thickness, at least four layers and comprise overlapped and non-overlapped circumferential areas; wherein the layer structure of the non-overlapped area is doubled in the overlapped layer. A method of making the structure includes providing a multilayer flow stream with at least four layers of thermoplastic resinous materials; feeding the multilayer flow stream to a distribution manifold of an annular die to form an annular multilayer flow stream; and removing the annular multilayer flow stream from the annular die to form the annular multilayer structure. Also disclosed is an apparatus, comprising: a feedblock, with optional layer multiplier, that provides a multilayer flow stream of at least four layers to the manifold of an annular die; and an annular die having at least one distribution manifold that extrudes a multilayer flow stream.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.