US3857914A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for extruding a foamed, molded article
Assignee: Asahi Kasei Corp
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Filing: 1972-05-01
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Granted: 1974-12-31
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Expires: 1992-05-01
Abstract
Abstract A foamed, molded article having a skin core structure in which a skin layer is in a substantially unexpanded state and a core layer is in substantially expanded state. The article is prepared by introducing a flowable, expandable thermoplastic resin into a casting means having a plurality of partitioned passages, and externally cooling the passage containing the skin layer to solidify the skin layer substantially when it exits from the casting means while the material of the core layer is discharged from the casting means into a region of lower pressure to expand and become integrated with the solidified skin layer, forming the expansible or expanded resin having different expansibility or different degree of expansion from one another in the passages, and extruding the resin integrally.
Inventors
- 👤 I Aishima
- 👤 H Sakura
- 👤 H Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:45
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/36; B29C44/46; B29C44/468; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/695; B29C48/70; B29C48/03; B29C48/07; B29C48/08; Y; Y10; Y10S; Y10S264/00; Y10S264/13
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
194 words
A METHOD FOR CONTINUOUSLY EXTRUDING A FOAMED, MOLDED ARTICLE HAVING A SKIN-CORE STRUCTURE HAVING A SKIN LAYER AND A FOAM COARE, SAID SKIN LAYER HAVING A THICKNESS BETWEEN 0.5 AND 5 MM AND A DEGREE OF EXPANSION NO GREATER THAN 1.2, SAID METHOD COMPRISING INTODUCING A FLOWABLE, EXPANDABLE, THERMOPLASTIC RESIN FROM A SINGLE SOURCE INTO A SINGLE EXTRUDING DIE HAVING A PLURALITY OF PARTITIONED PASSAGES FOR RESPECTIVELY FORMING SKIN AND CORE LAYERS, EXTERNALLY COOLING THE RESIN PASSING THROUGH AT LEAST ONE OF THE PASSAGES FOR FORMING THE SKIN LAYER AT LEAST IN THE REGION OF THE OUTLET OF THE EXTRUDING DUE, THE SKIN LAYER BEING COOLED TO A TEMPERATURE LOWER THAN THE SOFTENING POINT OF THE RESIN TO SUBSTANTIALLY SOLIDIFY THE RESIN IN THE SUBSTANTIALLY UNEXPANDED STATE WHILE SIMULTANEOUSLY MAINTAINING THE RESIN PASSING THROUGH AT LEAST ONE PASSAGE FOR FORMING THE CORE LAYER IN A SUBSTANTIALLY UNEXPANDED STATE UNDER PRESSURE WITHOUT COOLING AND EXTRUDING ALL OF THE RESIN FROM THE EXTRUDING DIE INTO A LOWER PRESSURE ZONE IN WHICH THE RESIN FROM THE PASSAGE FOR FORMING THE CORE LAYER IS IMMEDIATELY EXPANDED TO BECOME INTEGRATED WITH THE SOLIDIFIED RESIN WHICH FORMS THE SKIN LAYER.
Claim 2
Independent Claim
194 words
A METHOD FOR CONTINUOUSLY EXTRUDING A FOAMED, MOLDED ARTICLE HAVING A SKIN-CORE STRUCTURE HAVING A SKIN LAYER AND A FOAM COARE, SAID SKIN LAYER HAVING A THICKNESS BETWEEN 0.5 AND 5 MM AND A DEGREE OF EXPANSION NO GREATER THAN 1.2, SAID METHOD COMPRISING INTODUCING A FLOWABLE, EXPANDABLE, THERMOPLASTIC RESIN FROM A SINGLE SOURCE INTO A SINGLE EXTRUDING DIE HAVING A PLURALITY OF PARTITIONED PASSAGES FOR RESPECTIVELY FORMING SKIN AND CORE LAYERS, EXTERNALLY COOLING THE RESIN PASSING THROUGH AT LEAST ONE OF THE PASSAGES FOR FORMING THE SKIN LAYER AT LEAST IN THE REGION OF THE OUTLET OF THE EXTRUDING DUE, THE SKIN LAYER BEING COOLED TO A TEMPERATURE LOWER THAN THE SOFTENING POINT OF THE RESIN TO SUBSTANTIALLY SOLIDIFY THE RESIN IN THE SUBSTANTIALLY UNEXPANDED STATE WHILE SIMULTANEOUSLY MAINTAINING THE RESIN PASSING THROUGH AT LEAST ONE PASSAGE FOR FORMING THE CORE LAYER IN A SUBSTANTIALLY UNEXPANDED STATE UNDER PRESSURE WITHOUT COOLING AND EXTRUDING ALL OF THE RESIN FROM THE EXTRUDING DIE INTO A LOWER PRESSURE ZONE IN WHICH THE RESIN FROM THE PASSAGE FOR FORMING THE CORE LAYER IS IMMEDIATELY EXPANDED TO BECOME INTEGRATED WITH THE SOLIDIFIED RESIN WHICH FORMS THE SKIN LAYER.
Claim 3
Dependent Claim
29 words
A method as claimed in claim 1 including the additional step of confining the article when it is discharged from the extruding die to maintain the desired shape thereof.
Claim 4
Dependent Claim
29 words
A method as claimed in claim 2 including the additional step of cooling the article in the region where it is being confined after discharge from the extruding die.
Claim 5
Dependent Claim
19 words
A method as claimed in claim 1 wherein the passages in the extruding die are annular and formed concentrically.
Claim 6
Dependent Claim
34 words
A method as claimed in claim 1 wherein the thermoplastic resin is selected from the group consisting of high density polyethylene, low density polyethylene, polypropylene, polystyrene, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer, polyacetal, polyamide and polyester.
Claim 7
Dependent Claim
13 words
A method as claimed in claim 1 wherein the thermoplastic resin is polyethylene.
Claim 8
Dependent Claim
13 words
A method as claimed in claim 1 wherein the thermoplastic resin is polypropylene.
Claim 9
Dependent Claim
13 words
A method as claimed in claim 1 wherein the thermoplastic resin is polystyrene.
Claim 10
Dependent Claim
14 words
A method as claimed in claim 1 wherein the thermoplastic resin is acrylonitrile-butadiene-styrene copolymer.
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US3327030A
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US3431163A
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US3461496A
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US3337914A
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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) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |