US4521487A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Particulate polyolefin expansion molding material
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1984-09-21
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Granted: 1985-06-04
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Expires: 2004-09-21
Abstract
Abstract A particulate polyolefin expansion molding material is disclosed. The material is comprised of a particulate polyolefin having a bulk density of 0.45 g/cc or more and a mean particle size of 150 to 2,000μ, having provided on the surface thereof at least one layer comprising an expanding agent, a binder and a filler. The material can be used in producing expansion molded articles without first forming the material into pellets as is conventionally done.
Inventors
- 👤 Tatsuyuki Mitsuno
- 👤 Masashi Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:29
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/06; C08J2323/00; C08J2323/02; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2998
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
64 words
A particulate polyolefin expansion molding material comprising a particulate polyolefin having a bulk density of 0.45 g/cc or more and a mean particle size of 150 to 2,000μ, said particles having coated on the surface thereof at least one layer comprising a solid decomposable expanding agent, a binder selected from the group consisting of olefinic polymers, petroleum resins and polyalkylene glycols and a filler.
Claim 2
Dependent Claim
64 words
A particulate polyolefin expansion molding material comprising a particulate polyolefin having a bulk density of 0.45 g/cc or more and a mean particle size of 150 to 2,000μ, said particles having coated on the surface thereof at least one layer comprising a solid decomposable expanding agent, a binder selected from the group consisting of olefinic polymers, petroleum resins and polyalkylene glycols and a filler.
Claim 3
Dependent Claim
36 words
A particulate polyolefin expansion molding material as claimed in claim 1, wherein said binder is in the molten state at a temperature lower than the melting point of said particulate polyolefin by at least 3° C.
Claim 4
Dependent Claim
22 words
A particulate polyolefin expansion molding material as claimed in claim 1, wherein said particulate polyolefin is a crystalline propylene homopolymer or copolymer.
Claim 5
Dependent Claim
36 words
A particulate polyolefin expansion molding material as claimed in claim 1, wherein said binder is in the molten state at a temperature lower than the decomposition temperature of said expanding agent by at least 5° C.
Claim 6
Dependent Claim
34 words
A particulate polyolefin expansion molding material as claimed in claim 1, wherein the amount of said expanding agent is 0.1 to 20 parts by weight per 100 parts by weight of said particulate polyolefin.
Claim 7
Dependent Claim
33 words
A particulate polyolefin expansion molding material as claimed in claim 1, wherein the amount of said filler is 0.1 to 150 parts by weight per 100 parts by weight of said particulate polyolefin.
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) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |