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US4238570A Expired / Lapsed US ⏱️ 0.0 years remaining

Novel expandable particles of a styrene polymer and process for preparing the same

Assignee: Resonac Corp
•
Filing: 1979-02-23
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Granted: 1980-12-09
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Expires: 1999-02-23
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Abstract

Abstract Expandable particles of a styrene polymer which comprise on the surface thereof an ester of an aliphatic carboxylic acid with an aliphatic alcohol, the ester having no hydroxyl group in the molecule and being a solid at room temperature, or a mixture of said ester and a finely divided lubricant, and a process for preparing the same.

Inventors

  • 👤 Hideaki Shibata
  • 👤 Michihisa Osawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 16:04
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/22; C08J9/224; C08J2325/00; C08J2325/02; C08J2325/04

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 60 words
Expandable particles of a styrene polymer containing a blowing agent, said particles having a surface coating consisting essentially of (i) an ester of a saturated fatty acid with a monohydric saturated aliphatic alcohol, or (ii) a triglyceride of a saturated fatty acid, said ester or triglyceride having no hydroxyl group in the molecule and being a solid at room temperature.
Claim 2
Dependent Claim 60 words
Expandable particles of a styrene polymer containing a blowing agent, said particles having a surface coating consisting essentially of (i) an ester of a saturated fatty acid with a monohydric saturated aliphatic alcohol, or (ii) a triglyceride of a saturated fatty acid, said ester or triglyceride having no hydroxyl group in the molecule and being a solid at room temperature.
Claim 3
Dependent Claim 42 words
Expandable particles of a styrene polymer according to claim 1 or claim 1 wherein said ester or triglyceride is contained on the surface of the particles in an amount of 0.03-0.5% by weight calculated on the expandable particles of a styrene polymer.
Claim 4
Dependent Claim 20 words
Expandable particles of a styrene polymer according to claim 1 wherein said coating has a melting point of 50°-110° C.
Claim 5
Dependent Claim 16 words
Expandable particles of a styrene polymer according to claim 1 wherein said coating is a triglyceride.
Claim 6
Dependent Claim 35 words
Expandable particles of a styrene polymer according to claim 1 wherein said finely divided lubricant and said ester or triglyceride are contained on the surface of the particles in a ratio of 1/1-1/300 by weight.
Claim 7
Dependent Claim 22 words
Expandable particles or a styrene polymer according to claim 1 wherein said lubricant is a metal soap or a fatty acid amide.
Claim 8
Dependent Claim 18 words
Expandable particles of a styrene polymer according to claim 1, wherein said ester comprises a finely divided lubricant.

References Cited (Backward Citations)

US2989782A Cited
US3560414A Cited
US3789028A Cited
US4003858A Cited
US4042541A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-12-09 1984-06-09 1984-12-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-12-09 1988-06-09 1988-12-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-12-09 1992-06-09 1992-12-09 $7700.00 Window Closed / Lapsed

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