Patent US4304872A successfully refreshed from Google Patents.
US4304872A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible polyurethane foams having substantial number of cells with internal residual cell surface of 60 to 90 percent
Assignee: BP Chemicals Ltd
•
Filing: 1980-04-24
•
Granted: 1981-12-08
•
Expires: 2000-04-24
Abstract
Abstract A novel flexible polyurethane foam has a substantial number of cells with an internal residual cell surface greater than 60% and less than 90%. The novel foams have improved vibration damping characteristics.
Inventors
- 👤 Rudolf J. Tenhagen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:01
CPC Classifications
C; C08; C08J; C08J9/00; C08J2375/00; C08J2375/04; Y; Y10; Y10S; Y10S264/00; Y10S264/13; Y10S521/00; Y10S521/904; Y10S521/918
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
25 words
A flexible polyurethane foam which has at least 50% of the cells with an internal residual cell surface greater than 60% and less than 90%.
Claim 2
Dependent Claim
25 words
A flexible polyurethane foam which has at least 50% of the cells with an internal residual cell surface greater than 60% and less than 90%.
Claim 3
Dependent Claim
26 words
A flexible polyurethane foam according to claim 1 wherein substantially all the cells have an internal residual cell surface greater than 60% and less than 90%.
Claim 4
Dependent Claim
28 words
A flexible polyurethane foam according to claim 1 wherein at least 50% of the cells have an internal residual cell surface greater than 70% and less than 90%.
Claim 5
Dependent Claim
17 words
A flexible polyurethane foam according to claim 1 wherein the breathability is not more than 2 SCFM.
Claim 6
Dependent Claim
23 words
A flexible polyurethane foam according to claim 4 wherein the surface breathability measured by the Gurley test is not less than 2 seconds.
Claim 7
Dependent Claim
18 words
A flexible polyurethane foam according to claim 5 wherein the surface breathability is not more than 20 seconds.
Claim 8
Dependent Claim
23 words
A flexible polyurethane foam according to claim 6 wherein the hardness as measured by the IFD ASTM test is at least 100 N.
References Cited (Backward Citations)
US3505377A
Cited
USRE27541E
Cited
US3741917A
Cited
US3887483A
Cited
US3839384A
Cited
US4031044A
Cited
US4071483A
Cited
US4119582A
Cited
DE2519004A1
Cited
FR2316272A1
Cited
US4016163A
Cited
US4067828A
Cited
GB1515956A
Cited
GB1515957A
Cited
FR2316274B1
Cited
FR2316273B1
Cited
US4039490A
Cited
US4150048A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-12-07 | 1985-06-08 | 1985-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-07 | 1989-06-08 | 1989-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-07 | 1993-06-08 | 1993-12-08 | $7700.00 | Window Closed / Lapsed |