US5032622A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Densifiable and re-expandable polyurethane foam
Assignee: Dow Chemical Co
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Filing: 1990-07-02
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Granted: 1991-07-16
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Expires: 2010-07-02
Abstract
Abstract Polyurethane foams having a specified glass transition temperature are densified for transportation or other purposes by heating the foam to a temperature above its T g , compressing the heated foam, and then cooling the compressed foam to a temperature below its T g . The cooled foam remains in a densified state until re-heated to a temperature above its T g , whereupon it re-expands to assume its original dimensions.
Inventors
- 👤 Ronald M. Herrington
- 👤 Robert B. Turner
- 👤 Robert M. Harnden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:24
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/36; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/48; C08G18/4804; C08G18/4812; C08G2110/00; C08G2110/0008; C08G2110/0041; C08G2110/0083; C08G2280/00; C08J2375/00; C08J2375/04; Y; Y10; Y10S; Y10S521/00; Y10S521/918
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
70 words
A densified polyurethane having a bulk density of from about 30 to about 900 kg/m 3 and a T g of at least about 35° C. but below the decomposition temperature of said polyurethane, which densified polyurethane is thermally expandable without the addition of a blowing agent to form a polyurethane foam having a bulk density of about 5 to about 25% of the bulk density of the densified polyurethane.
Claim 2
Dependent Claim
70 words
A densified polyurethane having a bulk density of from about 30 to about 900 kg/m 3 and a T g of at least about 35° C. but below the decomposition temperature of said polyurethane, which densified polyurethane is thermally expandable without the addition of a blowing agent to form a polyurethane foam having a bulk density of about 5 to about 25% of the bulk density of the densified polyurethane.
Claim 3
Dependent Claim
65 words
The densified polyurethane of claim 1 which is the reaction product of a reaction mixture comprising as a major active hydrogen-containing component a polyol having an equivalent weight from about 125 to about 350, a polyisocyanate, and at least about 5 parts water per 100 parts of combined weight of all active hydrogen-containing components, wherein the isocyanate index is from about 50 to about 110.
Claim 4
Dependent Claim
26 words
The densified polyurethane of claim 2 wherein said major active hydrogen-containing component is a polyether polyol having an equivalent weight from about 130 to about 250.
Claim 5
Dependent Claim
59 words
The densified polyurethane of claim 3 wherein said reaction mixture further comprises an additional active hydrogen-containing material having an equivalent weight of about 800 to about 3000, and wherein the number of equivalents of said major active hydrogen-containing component constitutes about 60 to about 98% of the total number of equivalents of all active hydrogen-containing materials other than water.
Claim 6
Dependent Claim
18 words
The densified polyurethane of claim 4 wherein said polyisocyanate is MDI, polymeric MDI, TDI or a mixture thereof.
Claim 7
Dependent Claim
81 words
A polyurethane foam having a T g of at least about 35° C. but below the decomposition temperature of said polyurethane, which foam is the reaction product of a reaction mixture comprising as a major active hydrogen-containing component a polyol having an equivalent weight from about 125 to about 350, a polyisocyanate, and at least about 5 parts water per 100 parts of combined weight of all active hydrogen-containing components, wherein the isocyanate index is from about 50 to about 110.
Claim 8
Dependent Claim
81 words
A polyurethane foam having a T g of at least about 35° C. but below the decomposition temperature of said polyurethane, which foam is the reaction product of a reaction mixture comprising as a major active hydrogen-containing component a polyol having an equivalent weight from about 125 to about 350, a polyisocyanate, and at least about 5 parts water per 100 parts of combined weight of all active hydrogen-containing components, wherein the isocyanate index is from about 50 to about 110.
Claim 9
Dependent Claim
25 words
The foam of claim 6 wherein said major active hydrogen-containing component is a polyether polyol having an equivalent weight from about 130 to about 250.
Claim 10
Dependent Claim
53 words
The foam of claim 7 wherein said reaction mixture further comprises an additional active hydrogen-containing material having an equivalent weight of about 800 to about 3000, and wherein said major active hydrogen-containing component constitutes about 60 to about 98% of the total number of equivalents of all active hydrogen-containing materials other than water.
Claim 11
Dependent Claim
17 words
The foam of claim 8 wherein said polyisocyanate is MDI, polymeric MDI, TDI or a mixture thereof.
Claim 12
Dependent Claim
22 words
The foam of claim 9 further comprising an amount of a non-volatile, ionizable metal salt sufficient to render the foam static dissipative.
Claim 13
Dependent Claim
76 words
A re-expanded polyurethane foam having a T g of at least about 35° C. but below the decomposition temperature of said polyurethane, which has been re-expanded by heating a densified polyurethane having a bulk density of about 30 to about 900 kg/m 3 to a temperature above its T g under conditions such that the densified polyurethane re-expands to assume a bulk density of less than about 25% of the bulk density of the densified polyurethane.
Claim 14
Dependent Claim
76 words
A re-expanded polyurethane foam having a T g of at least about 35° C. but below the decomposition temperature of said polyurethane, which has been re-expanded by heating a densified polyurethane having a bulk density of about 30 to about 900 kg/m 3 to a temperature above its T g under conditions such that the densified polyurethane re-expands to assume a bulk density of less than about 25% of the bulk density of the densified polyurethane.
Claim 15
Independent Claim
105 words
A method for densifying a polyurethane foam having a T g of at least about 35° C. but below the decomposition temperature of said polyurethane and an initial bulk density, comprising bringing said foam to a temperature in excess of its T g but below said decomposition temperature, then compressing the heated foam sufficiently that the compressed foam has a bulk density from about 4 to about 20 times the initial bulk density of the polyurethane foam, but not greater than about 900 kg/m 3 , then cooling the foam to a temperature below about 30° C. while maintaining the foam in said compressed state.
Claim 16
Independent Claim
105 words
A method for densifying a polyurethane foam having a T g of at least about 35° C. but below the decomposition temperature of said polyurethane and an initial bulk density, comprising bringing said foam to a temperature in excess of its T g but below said decomposition temperature, then compressing the heated foam sufficiently that the compressed foam has a bulk density from about 4 to about 20 times the initial bulk density of the polyurethane foam, but not greater than about 900 kg/m 3 , then cooling the foam to a temperature below about 30° C. while maintaining the foam in said compressed state.
Claim 17
Dependent Claim
13 words
A loose-fill packing comprising a foam of claim 6 in a particulate form.
References Cited (Backward Citations)
US4980386A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-15 | 1995-01-14 | 1995-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-15 | 1999-01-14 | 1999-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-15 | 2003-01-14 | 2003-07-16 | $7700.00 | Window Closed / Lapsed |