US5723510A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing thermoplastic polyester foam sheet
Assignee: Furukawa Electric Co Ltd
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Filing: 1996-06-11
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Granted: 1998-03-03
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Expires: 2016-06-11
Abstract
Abstract A method of manufacturing a thermoplastic polyester foam sheet comprises forming a roll by overlapping a thermoplastic polyester sheet and a separator on each other and rolling them, impregnating an inert gas into the thermoplastic polyester sheet while the roll is kept in a pressurized inert gas atmosphere, and foaming the thermoplastic polyester sheet by heating it under atmospheric pressure.
Inventors
- 👤 Akira Kabumoto
- 👤 Naoki Yoshida
- 👤 Masayasu Ito
- 👤 Mitsunori Okada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:07
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/3442; B29C44/3446; B29C44/3453; C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; C08J9/122; C08J2367/00; C08J2367/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
125 words
A method of manufacturing a thermoplastic polyester foam sheet comprising the steps of: forming a roll by overlapping and rolling a thermoplastic polyester sheet and a separator, said separator being formed of a nonwoven fabric having a weight per area of 20 to 100 g/m 2 and a thickness of 50 to 300 μm; impregnating said thermoplastic polyester sheet with carbon dioxide gas while said roll is kept in a pressurized carbon dioxide atmosphere of at least 30 kg/cm 2 to thereby attain a degree of crystallinity in said thermoplastic polyester sheet of at least 30%; and heating said thermoplastic polyester sheet under atmospheric pressure to a temperature ranging from a glass transition point to a melting point to thereby foam said thermoplastic polyester sheet.
Claim 2
Independent Claim
125 words
A method of manufacturing a thermoplastic polyester foam sheet comprising the steps of: forming a roll by overlapping and rolling a thermoplastic polyester sheet and a separator, said separator being formed of a nonwoven fabric having a weight per area of 20 to 100 g/m 2 and a thickness of 50 to 300 μm; impregnating said thermoplastic polyester sheet with carbon dioxide gas while said roll is kept in a pressurized carbon dioxide atmosphere of at least 30 kg/cm 2 to thereby attain a degree of crystallinity in said thermoplastic polyester sheet of at least 30%; and heating said thermoplastic polyester sheet under atmospheric pressure to a temperature ranging from a glass transition point to a melting point to thereby foam said thermoplastic polyester sheet.
Claim 3
Dependent Claim
13 words
The method according to claim 1, wherein said thermoplastic polyester comprises polyethylene telephthalate.
Claim 4
Dependent Claim
17 words
The method according to claim 1, wherein said nonwoven fabric comprises one of polyolefin, nylon, and polyester.
Claim 5
Dependent Claim
25 words
The method according to claim 1, wherein a pressure of the carbon dioxide atmosphere in which said roll in kept is at least 50 kg/cm2.
Claim 6
Dependent Claim
22 words
The method according to claim 1, wherein said roll is kept in the pressurized carbon dioxide atmosphere for at least one hour.
Claim 7
Dependent Claim
26 words
The method according to claim 1, wherein an organic solvent is impregnated into said roll before said roll is kept in the pressurized carbon dioxide atmosphere.
Claim 8
Dependent Claim
29 words
The method according to claim 6, wherein a degree of crystallinity of said thermoplastic polyester sheet after said organic solvent is impregnated into said roll is at least 30%.
Claim 9
Dependent Claim
12 words
The method according to claim 6, wherein said organic solvent comprises acetone.
Claim 10
Dependent Claim
32 words
The method according to claim 1, wherein acetone is impregnated into said roll by keeping said roll in an acetone vapor, before said roll is kept in the pressurized carbon dioxide atmosphere.
References Cited (Backward Citations)
US4473665A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-03-02 | 2001-09-01 | 2002-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-03-02 | 2005-09-01 | 2006-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-03-02 | 2009-09-01 | 2010-03-03 | $7700.00 | Window Closed / Lapsed |