US4911978A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyolefin resin foamed laminate sheet and double-side vacuum forming of the same
Assignee: Sekisui Kaseihin Kogyo KK
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Filing: 1989-05-30
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Granted: 1990-03-27
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Expires: 2009-05-30
Abstract
Abstract A foamed laminate sheet suitable for thermoforming and a double-side vacuum forming process using the same are disclosed, said foamed laminate sheet being composed of a foamed interlayer comprising a polyolefin resin as a main resinous component and from 0.5 to 35 parts by weight of an inorganic filler per 100 parts by weight of the polyolefin resin, said foamed interlayer having a density of from 0.18 to 0.98 g/cm 3 , and a polyolefin film laminated on both sides of said foamed interlayer. The foamed laminate sheet exhibits excellent formability, and formings obtained therefrom have excellent heat resistance, oil resistance, heat insulating properties, and strength, with outstanding use in a microwave oven or as a retort food container.
Inventors
- 👤 Masahiro Tsubone
- 👤 Yoshinori Kajimoto
- 👤 Toru Yoshimi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:29
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/18; B29; B29C; B29C44/00; B29C44/02; B29C44/12; B29C44/14; B29C44/16; B29C51/00; B29C51/14; B32B27/00; B32B27/06; B32B27/065; B32B27/18; B32B27/20; B32B27/32; B29C51/10; B32B2266/00; B32B2266/02; B32B2266/0214; B32B2266/025; B32B2323/00; B32B2323/10; B32B2439/00; B32B2439/70; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1376; Y10T428/24; Y10T428/24479; Y10T428/24496; Y10T428/24504; Y10T428/249921; Y10T428/249953; Y10T428/249986; Y10T428/249987; Y10T428/249991; Y10T428/249992; Y10T428/249993
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
70 words
A foamed laminate sheet suitable for thermoforming, which is composed of a foamed interlayer comprising a polyolefin resin as a main resinous component and from 0.5 to 35 parts by weight of an inorganic filler per 100 parts by weight of the polyolefin resin, said foamed interlayer having a density of from 0.18 to 0.98 g/cm 3 , and a polyolefin film laminated on both sides of said foamed interlayer.
Claim 2
Dependent Claim
70 words
A foamed laminate sheet suitable for thermoforming, which is composed of a foamed interlayer comprising a polyolefin resin as a main resinous component and from 0.5 to 35 parts by weight of an inorganic filler per 100 parts by weight of the polyolefin resin, said foamed interlayer having a density of from 0.18 to 0.98 g/cm 3 , and a polyolefin film laminated on both sides of said foamed interlayer.
Claim 3
Dependent Claim
17 words
A foamed laminate sheet as claimed in claim 1, wherein said polyolefin resin is a polypropylene resin.
Claim 4
Dependent Claim
18 words
A foamed laminate sheet as claimed in claim 1, wherein said foamed interlayer further comprises a polystyrene resin.
Claim 5
Dependent Claim
37 words
A foamed laminate sheet as claimed in claim 3, wherein said foamed interlayer further comprises from 2 to 30 parts by weight of a saturated thermoplastic elastomer per 100 parts by weight of the total resinous components.
Claim 6
Dependent Claim
35 words
A foamed laminate sheet as claimed in claim 1, wherein said inorganic filler is present in an amount of from 10 to 20 parts by weight per 100 parts by weight of the polyolefin resin.
Claim 7
Dependent Claim
33 words
A foamed laminate sheet as claimed in claim 1, wherein said polyolefin film contains from 0.5 to 10 parts by weight of an inorganic filler per 100 parts by weight of the polyolefin.
Claim 8
Dependent Claim
83 words
A process of double-side vacuum forming of a polyolefin resin foamed laminate sheet by using male and female molds, in which a foamed laminate sheet composed of a polyolefin resin foamed interlayer having a density of from 0.18 to 0.98 g/cm 3 and a polyolefin film laminated on both sides of said interlayer is vacuum-formed between the male and female molds having a gap therebetween, said gap being from 1.0 to 2.5 times the thickness of the foamed laminate sheet heated and softened.
Claim 9
Dependent Claim
83 words
A process of double-side vacuum forming of a polyolefin resin foamed laminate sheet by using male and female molds, in which a foamed laminate sheet composed of a polyolefin resin foamed interlayer having a density of from 0.18 to 0.98 g/cm 3 and a polyolefin film laminated on both sides of said interlayer is vacuum-formed between the male and female molds having a gap therebetween, said gap being from 1.0 to 2.5 times the thickness of the foamed laminate sheet heated and softened.
Claim 10
Dependent Claim
36 words
A process of double-side vacuum forming as claimed in claim 7, wherein said foamed interlayer comprises 100 parts by weight of a polyolefin resin and from 0.5 to 35 parts by weight of an inorganic filler.
Claim 11
Dependent Claim
27 words
A process of double-side vacuum forming as claimed in claim 7, wherein said male and female molds are set at a temperature of 50° C. or lower.
Claim 12
Dependent Claim
85 words
A formed article obtained by double-side vacuum forming of a polyolefin resin foamed laminate sheet by using male and female molds, in which a foamed laminate sheet composed of a polyolefin resin foamed interlayer having a density of from 0.18 to 0.98 g/cm 3 and a polyolefin film laminated on both sides of said interlayer is vacuum-formed between the male and female molds having a gap therebetween, said gap being from 1.0 to 2.5 times the thickness of the foamed laminate sheet heated and softened.
Claim 13
Dependent Claim
85 words
A formed article obtained by double-side vacuum forming of a polyolefin resin foamed laminate sheet by using male and female molds, in which a foamed laminate sheet composed of a polyolefin resin foamed interlayer having a density of from 0.18 to 0.98 g/cm 3 and a polyolefin film laminated on both sides of said interlayer is vacuum-formed between the male and female molds having a gap therebetween, said gap being from 1.0 to 2.5 times the thickness of the foamed laminate sheet heated and softened.
Claim 14
Dependent Claim
16 words
A formed article as claimed in claim 10, wherein said polyolefin resin is a polypropylene resin.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-26 | 1993-09-25 | 1994-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-26 | 1997-09-25 | 1998-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-26 | 2001-09-25 | 2002-03-27 | $7700.00 | Window Closed / Lapsed |