Patent EP0376064A2 successfully refreshed from Google Patents.
EP0376064A2
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EP
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Method for producing a foamed resin
Assignee: Toyo Engineering Corp
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Filing: 1989-12-13
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Granted: —
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Expires: 2009-12-13
Abstract
Abstract There is disclosed a method for producing a foamed resin which comprises removing volatile substances from a polymer by contacting with an extractant and foaming the purified polymer by using the same extractant dissolved in the polymer as a foaming agent. According to the disclosure the purification and blowing of a polymer can be carried out efficiently and economically with a purification to such an extent to meet the market demand and with a desired blowing expansion rate.
Inventors
- 👤 Hisashi Miyakawa
- 👤 Takanobu Shinohara
- 👤 Tetsuo Maeda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 04:50
CPC Classifications
B; B01; B01D; B01D11/00; B01D11/02; B01D11/0203; C; C08; C08G; C08G85/00; C08J; C08J9/00; C08J9/04; C08J9/12; C08J9/122; C08J9/14
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
47 words
In a method for producing a foam, the improvement comprising bringing a polymer in contact with an extractant under pressure to remove volatile substances remaining in the polymer and then conducting foam molding using the extractant dissolved in the polymer as a blowing agent for the molding.
Claim 2
Dependent Claim
47 words
In a method for producing a foam, the improvement comprising bringing a polymer in contact with an extractant under pressure to remove volatile substances remaining in the polymer and then conducting foam molding using the extractant dissolved in the polymer as a blowing agent for the molding.
Claim 3
Dependent Claim
20 words
The method as claimed in claim 1, wherein the extractant in the extraction operation is used in the supercritical state.
Claim 4
Dependent Claim
20 words
The method as claimed in claim 1, wherein the extractant in the extraction operation is used in the sub-critical state.
Claim 5
Dependent Claim
62 words
The method as claimed in claim 1, wherein the polymer is a thermoplastic polymer selected from the group consisting of polyethylene, polypropylene, polystyrene, acrylonitrile/styrene copolymer, acrylonitrile/butadiene/styrene terpolymer, polyvinyl acetate, polyacrylate, polymethacrylate, polyvinyl chloride, polyvinylidene chloride, fluorocarbon polymers, polyacrylonitrile, polyvinyl ether, polyvinyl ketone, polyethers, thermoplastic polyesters, polyamides, styrene/butadiene polymers, diene polymers, polyurethane polymers, urea polymers, phenol polymers, polyxylylene, polycarbonate, polyphenylene oxide, and polysulfone.
Claim 6
Dependent Claim
25 words
The method as claimed in claim 1, wherein the polymer is a polystyrene polymer that is in the form of a powder, beads, or pellets.
Claim 7
Dependent Claim
18 words
The method as claimed in claim 1, wherein the polymer is a liquid composition containing a polystyrene polymer.
Claim 8
Dependent Claim
41 words
The method as claimed in claim 1, wherein the extractant or blowing agent is selected from the group consisting of carbon dioxide, dinitrogen oxide, carbon disulfide, an aliphatic hydrocarbon, a halogenated hydrocarbon, an aromatic hydrocarbon, and a mixture made up thereof.
Claim 9
Dependent Claim
23 words
The method as claimed in claim 1, wherein the pressure in the extraction operation is in a range of 20 to 500 kg/cm²G.
Claim 10
Dependent Claim
27 words
The method as claimed in claim 1, wherein the temperature in the extraction operation is at or over the melting point of the polymer to be purified.
Claim 11
Dependent Claim
26 words
The method as claimed in claim 1, wherein the volatile substances to be removed is an impurities selected from an unreacted monomer, solvent, or an oligomer.
Claim 12
Dependent Claim
21 words
The method as claimed in claim 1, wherein the extractor to be used in the extraction operation is a tank-type extractor.
Claim 13
Dependent Claim
29 words
The method as claimed in claim 1, wherein the extractor to be used in the extraction operation is selected from a packed tower-type, tray tower-type, or spray tower-type extractor.
Claim 14
Dependent Claim
21 words
The method as claimed in claim 1, wherein as the extractor in the extraction operation plural extractors are arranged in parallel.
Claim 15
Dependent Claim
21 words
The method as claimed in claim 1, wherein as the extractor in the extractor operation plural extractors are arranged in series.
Claim 16
Dependent Claim
22 words
The method as claimed in claim 1, wherein the blowing operation is carried out in the extractor used in the extraction operation.
Claim 17
Dependent Claim
22 words
The method as claimed in claim 1, wherein the mold for foaming is previously placed in the extractor before the extraction operation.
Claim 18
Dependent Claim
30 words
The method as claimed in claim 1, wherein the foaming operation is carried out in a storage tank to which the polymer containing the extractant is supplied from the extractor.
Claim 19
Dependent Claim
30 words
The method as claimed in claim 17, wherein the storage tank is provided with a blow nozzle through which the polymer in a melted state is spouted out for foaming.
References Cited (Backward Citations)
No citation records indexed.
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