Patent US5360828A successfully refreshed from Google Patents.
US5360828A
Expired / Lapsed
US
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Biofoam II
Assignee: University of California
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Filing: 1994-03-21
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Granted: 1994-11-01
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Expires: 2014-03-21
Abstract
Abstract Biofoam is a rigid, microcellular organic foam made from organic materials derived from natural products and biological organisms. Starting materials include agar, agarose, gelatin, algin, alginates, gellan gum, and microcrystalline cellulose. The organic material is dissolved in a polar solvent, typically water, and the mixture is gelled. The water in the gel pores is replaced at least once with another solvent to reduce the pore size of the final biofoam. The solvent in the gel pores may be replaced several times. After the final replacement of solvent, the gel is frozen and freeze-dried to form a biofoam. Translucent biofoams are formed by selecting a final solvent that forms very small crystals. A variety of crystalline, fibrous, amorphous, or metallic additives may be incorporated into the foam structure to produce lightweight composite materials with enhanced strength and insulating properties.
Inventors
- 👤 Robert L. Morrison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:17
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0085; C08J9/28; C08J2201/00; C08J2201/04; C08J2201/048; C08J2201/054; C08J2305/00; C08J2389/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
66 words
A method for forming a rigid, microcellular biofoam, comprising: (a) dissolving a naturally occurring organic material in a primary solvent to form a mixture; (b) forming a gel from the mixture, where the pores in the gel are occupied by the primary solvent; (c) replacing the primary solvent with a second solvent; (d) freezing the gel; and (e) drying the gel to form an organic biofoam.
Claim 2
Independent Claim
66 words
A method for forming a rigid, microcellular biofoam, comprising: (a) dissolving a naturally occurring organic material in a primary solvent to form a mixture; (b) forming a gel from the mixture, where the pores in the gel are occupied by the primary solvent; (c) replacing the primary solvent with a second solvent; (d) freezing the gel; and (e) drying the gel to form an organic biofoam.
Claim 3
Dependent Claim
32 words
A method for forming a biofoam as recited in claim 1, wherein the naturally occurring organic material comprises at least one of agars, agarose, algins, alginates, gums, resins, gum resins, and gelatins.
Claim 4
Dependent Claim
19 words
A method for forming a biofoam as recited in claim 1, wherein the primary solvent comprises a polar solvent.
Claim 5
Dependent Claim
31 words
A method for forming a biofoam as recited in claim 1, wherein the primary solvent is selected from the group consisting of ketones, ethers, alcohols, aldehydes, amines, water, and mixtures thereof.
Claim 6
Dependent Claim
36 words
A method for forming a biofoam as recited in claim 1, wherein the primary solvent comprises water and the second solvent is selected from the group consisting of ketones, ethers, alcohols, aldehydes, amines, and mixtures thereof.
Claim 7
Dependent Claim
28 words
A method for forming a biofoam as recited in claim 1, further comprising the step of replacing the second solvent with a third solvent before freezing the gel.
Claim 8
Dependent Claim
23 words
A method for forming a biofoam as recited in claim 6, wherein the second solvent is soluble in the first and third solvents.
Claim 9
Dependent Claim
19 words
A method for forming a biofoam as recited in claim 6, wherein the third solvent comprises a nonpolar solvent.
Claim 10
Dependent Claim
27 words
A method for forming a biofoam as recited in claim 6, wherein the third solvent is selected from the group consisting of nonpolar hydrocarbons and nonpolar aromatics.
Claim 11
Dependent Claim
30 words
A method for forming a biofoam as recited in claim 9, wherein the third solvent is selected from the group consisting of 1,4-dimethylbenzene, cyclohexane, hexadecane, naphthalene, freons, and mixtures thereof.
Claim 12
Dependent Claim
31 words
A method for forming a biofoam as recited in claim 10, wherein the primary solvent comprises water, the second solvent comprises an alcohol, and the third solvent comprises 1,4-dimethylbenzene and cyclohexane.
Claim 13
Dependent Claim
20 words
A method for forming a biofoam as recited in claim 1, wherein the drying step is carried out by freeze-drying.
Claim 14
Dependent Claim
20 words
A method for forming a biofoam as recited in claim 1, wherein the drying step is carried out by evaporation.
Claim 15
Dependent Claim
32 words
A method for forming a biofoam as recited in claim 1, further comprising the step of adding an additive to the mixture before forming the gel to produce a composite biofoam material.
Claim 16
Dependent Claim
27 words
A method for forming a biofoam as recited in claim 14, wherein the additive is selected from the group consisting of fibers, carbon powder, and metal powders.
Claim 17
Dependent Claim
40 words
A method for forming a biofoam as recited in claim 14, wherein the additive is selected from the group consisting of graphite fibers, microcrystalline cellulose, sawdust, amadine fibers, cotton fibers, polyester fibers, fiberglass, alkali tetratitanate, metal powders, and carbon powder.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-10-31 | 1998-05-02 | 1998-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-31 | 2002-05-02 | 2002-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-10-31 | 2006-05-02 | 2006-11-01 | $7700.00 | Window Closed / Lapsed |