Foamed thermoplastic resin sheet and manufacturing method of the same
US6815047B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1998 |
| Grant date | Nov 9, 2004 |
| Priority date | — |
| Expiry date | Apr 1, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249993
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A foamed thermoplastic resin sheet has a foaming ratio of not less than 2.5, and cells, existing in an interior part which extends inward from a depth of 20 percent a whole thickness of the sheet from the front and rear surfaces thereof respectively in a thickness direction thereof and from 15 percent a width of the sheet from both side edges respectively, satisfy the following expressions (1) and (2):0.5≦D/C≦0.9  (1) 0.5≦E/C≦0.9  (2) where C represents a mean cell diameter in the thickness direction of the foamed thermoplastic resin sheet, D represents a mean cell diameter in an extrusion direction (MD) of the same, and E represents a mean cell diameter in the width direction (TD) of the same. The foamed thermoplastic resin sheet thus arranged has a high foaming ratio, and is formed thick.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.