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US3954924A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for simultaneously casting sheets on blocks of cellular polymeric material

Assignee: Imperial Chemical Industries Ltd
•
Filing: 1973-05-31
•
Granted: 1976-05-04
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Expires: 1993-05-31
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Abstract

Abstract Sheets of cellular polymeric material are cast from a water-in-oil emulsion in a mould subdivided by one or more partitions.

Inventors

  • 👤 Roger Albert Castro
  • 👤 Richard John Orman
  • 👤 James Ernest Ryan

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 16:17
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/28; C08J9/283; Y; Y10; Y10S; Y10S264/00; Y10S264/14

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 143 words
A method for the simultaneous casting of a plurality of sheets or blocks of cellular polymeric material, comprising forming an emulsion having an aqueous disperse phase and a continuous phase comprising a polymerizable liquid consisting of 80 to 100 percent by weight of methyl methacrylate and 20 to 0 percent by weight of a liquid miscible and copolymerizable with the methyl methacrylate, and polymerizing said polymerizable liquid in a mold having one or more removable partitions which subdivide the emulsion during polymerization into the shapes of said sheets or blocks, the mold being thermally lagged against heat loss and the aqueous phase constituting at least 70 percent water by weight of the emulsion whereby heat evolved during polymerization is absorbed by the disperse phase and the temperature of the emulsion maintained below the boiling point of the lowest boiling fraction of said emulsion.
Claim 2
Independent Claim 143 words
A method for the simultaneous casting of a plurality of sheets or blocks of cellular polymeric material, comprising forming an emulsion having an aqueous disperse phase and a continuous phase comprising a polymerizable liquid consisting of 80 to 100 percent by weight of methyl methacrylate and 20 to 0 percent by weight of a liquid miscible and copolymerizable with the methyl methacrylate, and polymerizing said polymerizable liquid in a mold having one or more removable partitions which subdivide the emulsion during polymerization into the shapes of said sheets or blocks, the mold being thermally lagged against heat loss and the aqueous phase constituting at least 70 percent water by weight of the emulsion whereby heat evolved during polymerization is absorbed by the disperse phase and the temperature of the emulsion maintained below the boiling point of the lowest boiling fraction of said emulsion.
Claim 3
Dependent Claim 26 words
A method according to claim 1 in which the mould is sub-divided by inserting the partitions into the mould after the mould has received the emulsion.
Claim 4
Dependent Claim 33 words
A method according to claim 2 which comprises adding separately to the mould the constituents of the continuous phase and the aqueous disperse phase respectively, and emulsifying the two phases in the mould.

References Cited (Backward Citations)

US3442991A Cited
US3551541A Cited
US3802949A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-05-04 1979-11-03 1980-05-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-05-04 1983-11-03 1984-05-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-05-04 1987-11-03 1988-05-04 $7700.00 Window Closed / Lapsed

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