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US3956202A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparing low smoke-generating rigid polyurethane foam

Assignee: Achilles Corp
•
Filing: 1974-04-26
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Granted: 1976-05-11
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Expires: 1994-04-26
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Abstract

Abstract A process for preparing rigid polyurethane foam in which the major ingredients are a polyisocyanate, a polyol having more than three hydroxy groups and a hydroxyl value greater than 100, and blowing agents, comprising adjusting the ratio of the chemical equivalent of polyisocyanate to the polyol and blowing agent which react with the polyisocyanate to the range between 2 : 1 and 1 : 1, and adding a polymer of glucose and/or a derivative thereof in the form of a powder in the amount exceeding 5% by weight.

Inventors

  • 👤 Kazuo Iwasaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 23:05
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0061; C08J2375/00; C08J2375/04; C08J2401/00; C08J2403/00; Y; Y10; Y10S; Y10S521/00; Y10S521/903

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 117 words
In a low smoke generating rigid polyurethane obtained by heating (A) a polyisocyanate, (B) a polyol having three or more hydroxy groups and a hydroxyl value of 100 and more than 100, and (C) a blowing agent, the improvement which comprises said ingredients (A), (B), and (C) being present in a ratio of chemical equivalents of 1 to 2 parts of ingredient (A) for 1 part of ingredients (B) and (C) combined which react with said ingredient (A), and mixed with at least one member selected from the group consisting of alkyl cellulose, carboxymethyl cellulose, acetyl starch, nitro starch and carboxymethyl starch in the form of powders in an amount exceeding 5% by weight of the composition.
Claim 2
Dependent Claim 117 words
In a low smoke generating rigid polyurethane obtained by heating (A) a polyisocyanate, (B) a polyol having three or more hydroxy groups and a hydroxyl value of 100 and more than 100, and (C) a blowing agent, the improvement which comprises said ingredients (A), (B), and (C) being present in a ratio of chemical equivalents of 1 to 2 parts of ingredient (A) for 1 part of ingredients (B) and (C) combined which react with said ingredient (A), and mixed with at least one member selected from the group consisting of alkyl cellulose, carboxymethyl cellulose, acetyl starch, nitro starch and carboxymethyl starch in the form of powders in an amount exceeding 5% by weight of the composition.
Claim 3
Dependent Claim 23 words
The foam according to claim 1, in which a phosphoric ester, a metal oxide, or mixture thereof is used as a flame retardant.
Claim 4
Dependent Claim 23 words
The foam according to claim 2, in which the flame retardant is used in an amount of 10% by weight of the polyol.
Claim 5
Dependent Claim 107 words
In a process for preparing rigid polyurethane foam by mixing a polyisocyanate, a polyol having more than three hydroxy groups and a hydroxyl value equal to or greater than 100, and blowing agents, the improvement which comprises adjusting the ratio in chemical equivalent of polyisocyanate to the polyol and blowing agent which react with the polyisocyanate in the range between 2 : 1 and 1 : 1, and adding a polymer selected from the group consisting of alkyl cellulose, carboxymethyl cellulose, acetyl starch, nitro starch and carboxymethyl starch in the form of powders in an amount exceeding 5% by weight of the composition to the reaction mixture.
Claim 6
Dependent Claim 107 words
In a process for preparing rigid polyurethane foam by mixing a polyisocyanate, a polyol having more than three hydroxy groups and a hydroxyl value equal to or greater than 100, and blowing agents, the improvement which comprises adjusting the ratio in chemical equivalent of polyisocyanate to the polyol and blowing agent which react with the polyisocyanate in the range between 2 : 1 and 1 : 1, and adding a polymer selected from the group consisting of alkyl cellulose, carboxymethyl cellulose, acetyl starch, nitro starch and carboxymethyl starch in the form of powders in an amount exceeding 5% by weight of the composition to the reaction mixture.

References Cited (Backward Citations)

CA705937A Cited
US2999823A Cited
US3004934A Cited
US3674717A Cited
US3836487A Cited
US3714047A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-05-11 1979-11-10 1980-05-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-05-11 1983-11-10 1984-05-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-05-11 1987-11-10 1988-05-11 $7700.00 Window Closed / Lapsed

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