US4528221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polystyrene foamed sheet suitable for forming
Assignee: Sekisui Kaseihin Kogyo KK
•
Filing: 1983-05-10
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Granted: 1985-07-09
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Expires: 2003-05-10
Abstract
Abstract A polystyrene foamed sheet suitable for thermoforming and containers such as cups or trays formed therefrom, the foamed sheet comprising a polystyrene resin as the base resin which contains a specific quantity of each a rubber component and a filler, having specific bulk density, thickness, stretch ratio and residual gas quantity, and said sheet being preferably laminated with a film.
Inventors
- 👤 Nobuyuki Komatsuzaki
- 👤 Masahiro Tsubone
- 👤 Bon Machida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 01:56
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/065; C; C08; C08J; C08J9/00; C08J9/04; B32B27/30; B32B27/302; B32B27/32; B32B27/36; B32B5/00; B32B5/18; B32B7/00; B32B7/04; B32B7/12; B65; B65D; B65D1/00; B65D1/22; B65D1/26; B65D1/28; B32B2266/00; B32B2266/02; B32B2266/0214; B32B2266/0221; B32B2266/0228; B32B2307/00; B32B2307/70; B32B2307/718; B32B2309/00; B32B2309/08; B32B2309/10; B32B2309/105; B32B2367/00; B32B2439/00; B32B2439/02; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1376; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/249921; Y10T428/249953; Y10T428/249987; Y10T428/249988; Y10T428/249991; Y10T428/249992; Y10T428/249993; Y10T428/26; Y10T428/269
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
87 words
A polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio less than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg, said foamed sheet being laminated with a non-foamed film on at least one surface thereof.
Claim 2
Dependent Claim
87 words
A polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio less than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg, said foamed sheet being laminated with a non-foamed film on at least one surface thereof.
Claim 3
Dependent Claim
20 words
A polystyrene foamed sheet of claim 1, in which the quantity of the rubber component is 1 to 20 wt%.
Claim 4
Dependent Claim
20 words
A polystyrene foamed sheet of claim 1, in which the quantity of the rubber component is 1 to 7 wt%.
Claim 5
Dependent Claim
19 words
A polystyrene foamed sheet of claim 1, in which the quantity of the filler is 1.5 to 10 wt%.
Claim 6
Dependent Claim
20 words
A polystyrene foamed sheet of claim 1, in which the quantity of the residual gas is 0.03 to 0.3 mole/kg.
Claim 7
Dependent Claim
80 words
A container formed of a polystyrene foamed sheet, said polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio less than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg.
Claim 8
Dependent Claim
80 words
A container formed of a polystyrene foamed sheet, said polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio less than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg.
Claim 9
Dependent Claim
98 words
A container formed of a laminate of a polystyrene foamed sheet and a non-foamed film laminated on at least one surface of the polystyrene foamed sheet, said polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio less than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg.
Claim 10
Dependent Claim
98 words
A container formed of a laminate of a polystyrene foamed sheet and a non-foamed film laminated on at least one surface of the polystyrene foamed sheet, said polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio less than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg.
Claim 11
Dependent Claim
25 words
The container of claim 6 or 7, in which the quantity of the rubber component in the polystyrene foamed sheet is 1 to 20 wt%.
Claim 12
Dependent Claim
25 words
The container of claim 6 or 7, in which the quantity of the rubber component in the polystyrene foamed sheet is 1 to 7 wt%.
Claim 13
Dependent Claim
24 words
The container of claim 6 or 7, in which the quantity of the filler in the polystyrene foamed sheet is 1.5 to 10 wt%.
Claim 14
Dependent Claim
20 words
The container of claim 6 or 7, in which the quantity of the residual gas is 0.03 to 0.3 mole/kg.
Claim 15
Dependent Claim
16 words
The container of claim 7, in which the non-foamed film has a thickness of 5-600 μm.
Claim 16
Dependent Claim
19 words
The container of claim 7, in which the non-foamed film is polystyrene, polyethylene, high-impact polystyrene, polypropylene or polyethylene terephthalate.
Claim 17
Dependent Claim
15 words
The container of claim 7, in which the non-foamed film is polystyrene or high-impact polystyrene.
Claim 18
Dependent Claim
72 words
A polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio lss than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg.
Claim 19
Dependent Claim
72 words
A polystyrene foamed sheet comprising a polystyrene resin as the base resin which contains 1 to 30 wt% of a rubber component and 1 to 20 wt% of a filler based on said polystyrene, having a bulk density of 0.13 to 0.7 g/cm 3 , a thickness of 0.4 to 3.0 mm, a stretch ratio lss than 1.25 and a quantity of residual gas of a blowing agent less than 0.3 mole/kg.
Claim 20
Dependent Claim
20 words
A polystyrene foamed sheet of claim 15, in which the quantity of the rubber component is 1 to 20 wt%.
Claim 21
Dependent Claim
20 words
A polystyrene foamed sheet of claim 15, in which the quantity of the rubber component is 1 to 7 wt%.
Claim 22
Dependent Claim
19 words
A polystyrene foamed sheet of claim 15, in which the quantity of the filler is 1.5 to 10 wt%.
Claim 23
Dependent Claim
20 words
A polystyrene foamed sheet of claim 15, in which the quantity of the residual gas is 0.03 to 0.3 mole/kg.
Claim 24
Dependent Claim
18 words
A polystyrene foamed sheet of claim 1, in which the non-foamed film has a thickness of 5-600 μm.
Claim 25
Dependent Claim
21 words
A polystyrene foamed sheet of claim 1, in which the non-foamed film is polystyrene, polyethylene, high-impact polystyrene, polypropylene or polyethylene terephthalate.
Claim 26
Dependent Claim
17 words
A polystyrene foamed sheet of claim 1, in which the non-foamed film is polystyrene or high-impact polystyrene.
References Cited (Backward Citations)
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US4463861A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-08 | 1989-01-07 | 1989-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-08 | 1993-01-07 | 1993-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-08 | 1997-01-07 | 1997-07-09 | $7700.00 | Window Closed / Lapsed |