Patent US4942012A successfully refreshed from Google Patents.
US4942012A
Expired / Lapsed
US
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Preparation of laminated structures by thermoforming
Assignee: SABIC Global Technologies BV
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Filing: 1989-08-21
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Granted: 1990-07-17
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Expires: 2009-08-21
Abstract
Abstract Thermoplastic layers are vacuum thermoformed to produce laminated structures by perforating all layers to be formed except the layer outermost from the mold. Thus, the non-perforated layer is attracted to the mold, serving as a diaphragm for the other layers or consolidating therewith to form the desired article.
Inventors
- 👤 Walter J. Lee
- 👤 Catherine S. Hissem
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:09
CPC Classifications
B; B32; B32B; B32B43/00; B29; B29C; B29C51/00; B29C51/14; B29C51/26; B29C51/28; B29L; B29L2031/00; B29L2031/737
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
73 words
A method for producing a thermoformed article which comprises the steps of: feeding multiple layers of formable material to a mold while heating said mold, the layer outermost from the mold being non-perforated and the other layers being perforated; vacuum forming said layers to the mold contours, thus producing a molded article; heating the perforated layers to cause them to flow and seal the perforations; and removing said molded article from the mold.
Claim 2
Independent Claim
73 words
A method for producing a thermoformed article which comprises the steps of: feeding multiple layers of formable material to a mold while heating said mold, the layer outermost from the mold being non-perforated and the other layers being perforated; vacuum forming said layers to the mold contours, thus producing a molded article; heating the perforated layers to cause them to flow and seal the perforations; and removing said molded article from the mold.
Claim 3
Dependent Claim
13 words
A method according to claim 1 wherein the mold is a female mold.
Claim 4
Dependent Claim
16 words
A method according to claim 2 wherein the nonperforated layer forms part of the molded article.
Claim 5
Dependent Claim
14 words
A method according to claim 3 wherein the formable material comprises a thermoplastic resin.
Claim 6
Dependent Claim
12 words
A method according to claim 4 wherein the resin is a polyester.
Claim 7
Dependent Claim
12 words
A method according to claim 5 wherein the polyester is poly(butylene terephthalate).
Claim 8
Dependent Claim
22 words
A method according to claim 4 wherein the formable material is a composite comprising a fibrous substrate impregnated with said thermoplastic resin.
Claim 9
Dependent Claim
30 words
A method according to claim 2 wherein the nonperforated layer does not form part of the article but serves as a diaphragm to create a seal during the forming operation.
Claim 10
Dependent Claim
18 words
A method according to claim 8 wherein the formable material in the perforated layers comprises a thermoplastic resin.
Claim 11
Dependent Claim
12 words
A method according to claim 9 wherein the resin is a polyester.
Claim 12
Dependent Claim
12 words
A method according to claim 10 wherein the polyester is poly(butylene terephthalate).
Claim 13
Dependent Claim
22 words
A method according to claim 8 wherein the formable material is a composite comprising a fibrous substrate impregnated with said thermoplastic 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) | 1993-07-16 | 1994-01-15 | 1994-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-16 | 1998-01-15 | 1998-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-16 | 2002-01-15 | 2002-07-17 | $7700.00 | Window Closed / Lapsed |