US Patent No: 5,362,436
Number of patents in Portfolio can not be more than 2000
Polystyrene foam sheet useful for forming deep drawn articles, a process to produce those articles, and the deep drawn articles
Stats
-
Nov 8, 1994
Issued date -
Jun 22, 1993
filing date -
08/081,043
serial no -
In Force
status
Importance
Loading Importance Indicators...
Abstract
A polystyrene foam sheet comprising a polystyrene resin which contains 1 to 15 wt % of a rubber component having a majority of particle sizes less than about 0.45 microns has been found to be superior for forming deep drawn articles. Optionally one or two films may be extrusion coated or laminated to the foam sheet prior to thermoforming. Also disclosed is a method for thermoforming the foam sheet. Preheat the sheet, clamp the sheet between the matched male and female mold members, move the members into final position while applying a vacuum through both members to both sides of the foamed sheet and then chill formed foam to set a final shape.
Loading the Abstract Image...
First Claim
Related Publications
Loading Related Publications...
International Classification(s)
- [Classification Symbol]
- [Patents Count]
Cited Art
| Patent Info | (Count) | # Cites | Year |
|---|---|---|---|
|
|
|||
| 4,239,727 Method and apparatus for thermoforming thermoplastic foam articles | 27 | 1978 | |
| 4,359,160 Nestable foam cup with improved heat retention and the process for its manufacture | 35 | 1980 | |
|
|
|||
| 5,039,714 Rubber-modified polystyrene resin composition | 18 | 1989 | |
|
|
|||
| 4,493,922 Impact-resistant thermoplastic molding material | 32 | 1984 | |
|
|
|||
| 4,214,056 Method for preparing a monoalkenyl aromatic polyblend having a dispersed rubber phase as particles with a bimodal particle size distribution | 19 | 1979 | |
|
|
|||
| 4,528,221 Polystyrene foamed sheet suitable for forming | 41 | 1983 | |