Composite material having polypropylene foam layer
US5928776A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 1997 |
| Grant date | Jul 27, 1999 |
| Priority date | — |
| Expiry date | Nov 7, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249993
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A composite material having a skin layer, an intermediate, cushioning layer provided on one side of the skin layer, and a backing layer provided on the cushioning layer, wherein the backing layer is made of a non-crosslinked polypropylene resin foam and having a melting point MB in the range of 130-170.degree. C., wherein the cushioning layer is a crosslinked polypropylene resin foamed sheet having a gel fraction of 20-70% by weight. The cushioning layer has an endothermic peak in DSC curve at a peak temperature of PC which is in the range of 130-170.degree. C. and which is not smaller than (MB-15).degree. C. but not greater than (MB+10).degree. C. The endothermic peak has such an area at temperatures higher than MB that corresponds to a calorific value in the range of 3-30 J/g. The backing layer may be formed by expansion molding of expanded polypropylene particles within a mold cavity in which a laminate of the skin layer and the cushioning layer is placed in position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.