US4521544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyurethane foam from cellulosic products
Assignee: Individual
•
Filing: 1983-02-24
•
Granted: 1985-06-04
•
Expires: 2003-02-24
Abstract
Abstract A polyurethane foam can be made from waste cellulosic products such as papermill sludge, wood chips, wood particles, sawdust, waste paper or cardboard scraps. The polyurethane foam is made by reacting together a polyisocyanate, a catalyst, and a cellulosic material.
Inventors
- 👤 Richard B. Kennedy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 22:04
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/64; C08G18/6484; C08G18/30; C08G18/32; C08G18/3203; C08G18/3218
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
21 words
A polyurethane foam made by reacting together a polyisocyanate, a catalyst, a cellulosic material, and an aqueous solution of a carbohydrate.
Claim 2
Dependent Claim
21 words
A polyurethane foam made by reacting together a polyisocyanate, a catalyst, a cellulosic material, and an aqueous solution of a carbohydrate.
Claim 3
Dependent Claim
27 words
The polyurethane foam of claim 1 wherein the carbohydrate is selected from the group consisting of cornstarch, corn syrup, high fructose corn syrup, dextrose, sucrose, and molasses.
Claim 4
Dependent Claim
11 words
The polyurethane foam of claim 2 wherein the carbohydrate is cornstarch.
Claim 5
Dependent Claim
12 words
The polyurethane foam of claim 2 wherein the carbohydrate is corn syrup.
Claim 6
Dependent Claim
14 words
The polyurethane foam of claim 1 wherein the cellulosic material is underwatered papermill sludge.
Claim 7
Independent Claim
41 words
A method of making a polyurethane foam comprising: a. admixing a cellulosic material with a catalyst and an aqueous solution or slurry of a carbohydrate; b. combining the mixture of (a) and a polyisocyanate; and c. allowing the mixture to foam.
Claim 8
Independent Claim
41 words
A method of making a polyurethane foam comprising: a. admixing a cellulosic material with a catalyst and an aqueous solution or slurry of a carbohydrate; b. combining the mixture of (a) and a polyisocyanate; and c. allowing the mixture to foam.
Claim 9
Dependent Claim
26 words
The method of claim 6 wherein the carbohydrate is selected from the group consisting of cornstarch, corn syrup, dextrose, high fructose corn syrup, sucrose, and molasses.
Claim 10
Dependent Claim
12 words
The method of claim 6 wherein the cellulosic material is papermill sludge.
Claim 11
Dependent Claim
13 words
The method of claim 6 wherein a surfactant is mixed with the polyisocyanate.
Claim 12
Dependent Claim
18 words
The method of claim 6 wherein a flame retardant is mixed with the cellulosic material and the catalyst.
References Cited (Backward Citations)
US4230822A
Cited
US4400475A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |