Multilayer structures and process for fabricating the same
US5837380A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 1995 |
| Grant date | Nov 17, 1998 |
| Priority date | — |
| Expiry date | Dec 26, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31786
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A substantially warp-free laminate polymeric film structure is obtained by a fabrication process in which the individual layers of polymeric film that are to be laminated together to form a card or similar structure are selected such that the mechanical properties of one layer or pair of layers are offset by those of another layer or layer pair wherein each polymeric film layer is bonded to its adjacent polymeric film layers by adhesive layers wherein the adhesive layers have a tack point temperature that is within 10.degree. C. of the glass transition temperature of said polymeric film layers. The properties of the layers which may be subject to this consideration include, for example, the layer thickness, tensile strength, elongation factor, shrinkage rate, and machine processing direction. In an illustrative three-layer substrate embodiment of the present invention, the tensile strength, elongation factor, and shrinkage rate of the outer film layers of the substrate are the same, with the outer layers having a higher tensile strength value than the inner layer tensile strength. The orientation of the film's processing and machine direction and the orientation of the coil set of …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.