US4480089A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Modified cellulose products by bleaching
Assignee: Purdue Research Foundation
•
Filing: 1983-06-14
•
Granted: 1984-10-30
•
Expires: 2003-06-14
Abstract
Abstract Modified cellulose products for use as carrier vehicles in forming cosmetics, pharmaceutical preparations, insecticides, etc. are prepared by treating a minimum weight ratio of about 10:1 of fibrous cellulosic material with an alkali metal or alkaline earth metal hypohalite (e.g. sodium hypochlorite) at a temperature of from about 15° to 60° C. for a period of time sufficient to render the material non-fibrous (i.e. pH drop to about 6 or less), filtering and washing obtain the desired product.
Inventors
- 👤 Li F. Chen
- 👤 Parakkat Seethanathan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:09
CPC Classifications
A; A01; A01N; A01N25/00; A01N25/08; A01N25/10; A61; A61K; A61K47/00; A61K47/30; A61K47/36; A61K47/38; A61K8/00; A61K8/18; A61K8/72; A61K8/73; A61K8/731; A61K9/00; A61K9/0012; A61K9/0014; A61Q; A61Q17/00; A61Q17/02; A61Q17/04; C; C08; C08B; C08B15/00; C08B15/02
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
110 words
A method of making a modified cellulose product suitable for use as a carrier vehicle or bodying agent comprising the steps of treating a fibrous cellulose material with an alkali metal or alkaline earth metal hypohalite at a temperature ranging from about 15° to about 60° C. in an aqueous medium for a period of time sufficient to render the material non-fibrous, the weight ratio of fibrous cellulose material to hypohalite being from about 10:1 to 1:1 and the aqueous medium being present in a sufficient quantity to achieve uniform wetting of the fibrous material, filtering and washing the reaction material to remove salts and obtain a modified cellulose product.
Claim 2
Independent Claim
110 words
A method of making a modified cellulose product suitable for use as a carrier vehicle or bodying agent comprising the steps of treating a fibrous cellulose material with an alkali metal or alkaline earth metal hypohalite at a temperature ranging from about 15° to about 60° C. in an aqueous medium for a period of time sufficient to render the material non-fibrous, the weight ratio of fibrous cellulose material to hypohalite being from about 10:1 to 1:1 and the aqueous medium being present in a sufficient quantity to achieve uniform wetting of the fibrous material, filtering and washing the reaction material to remove salts and obtain a modified cellulose product.
Claim 3
Dependent Claim
28 words
A method according to claim 1 wherein said hypohalite is generated in-situ by the addition of elemental chlorine to the aqueous medium which contains caustic lime or soda.
Claim 4
Dependent Claim
21 words
A method according to claim 1 wherein said hypohalite is selected from the group consisting of sodium hypochlorite and calcium hypochlorite.
Claim 5
Dependent Claim
27 words
A method according to claim 3 wherein the said period of time is sufficient that the pH of the medium has dropped to about 6 or less.
Claim 6
Dependent Claim
27 words
A method according to claim 3 wherein the said period of time is sufficient that the pH of the medium has dropped to about 4 or less.
Claim 7
Dependent Claim
42 words
A method according to claim 1 wherein the product is resuspended in a liquid medium selected from the group consisting of water, a water miscible solvent and mixtures thereof, and subjected to high shear homogenization to produce a suspension, gel or cream.
Claim 8
Dependent Claim
24 words
A method according to claim 6 wherein from about 0.5 to about 50% by weight of said product is resuspended in the liquid medium.
Claim 9
Dependent Claim
35 words
A method according to claim 7 wherein from about 5 to about 10% by weight of said product is resuspended in the liquid medium and subjected to high shear homogenization to produce a thixotropic gel.
Claim 10
Dependent Claim
14 words
A method according to claim 6 wherein the suspension, gel or cream is dried.
Claim 11
Dependent Claim
11 words
A method according to claim 1 wherein the product is dried.
Claim 12
Dependent Claim
20 words
A method according to claim 1 wherein said fibrous cellulose material is purified wood pulp, cotton linter or cotton fibers.
Claim 13
Dependent Claim
17 words
A method according to claim 1 wherein said fibrous cellulose material is bagasse, corn stover or sawdust.
Claim 14
Dependent Claim
12 words
A method according to claim 1 wherein said temperature is room temperature.
Claim 15
Dependent Claim
17 words
A method according to claim 1 wherein said temperature is from about 30° to about 50° C.
Claim 16
Dependent Claim
24 words
A method according to claim 1 wherein the product is dried and combined with an active ingredient and compressed to a shape retentive form.
Claim 17
Dependent Claim
16 words
A method according to claim 15 wherein said form is a tablet, block, stick or briquette.
Claim 18
Dependent Claim
27 words
A method according to claim 6 wherein said product is resuspended together with an active ingredient in the liquid medium to form said suspension, gel or cream.
Claim 19
Dependent Claim
19 words
A method according to claim 17 wherein the suspension, gel or cream is dried to remove the liquid medium.
Claim 20
Dependent Claim
14 words
A method according to claim 17 wherein the active ingredient is an edible foodstuff.
Claim 21
Dependent Claim
16 words
A method according to claim 17 wherein the active ingredient is a pharmaceutical compound or composition.
Claim 22
Dependent Claim
17 words
A method according to claim 17 wherein the active ingredient is an insecticide, herbicide, rodenticide or fungicide.
Claim 23
Dependent Claim
13 words
A method according to claim 17 wherein the active ingredient is a fertilizer.
Claim 24
Dependent Claim
14 words
A method according to claim 17 wherein the active ingredient is a cosmetic composition.
Claim 25
Dependent Claim
15 words
A method according to claim 17 wherein the active ingredient is a pigment containing composition.
References Cited (Backward Citations)
US2046551A
Cited
US2100496A
Cited
US2663907A
Cited
US2978446A
Cited
US3020197A
Cited
FR1374770A
Cited
US3976538A
Cited
US4081317A
Cited
US3992250A
Cited
US4236891A
Cited
US4269859A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-30 | 1988-04-30 | 1988-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-30 | 1992-04-30 | 1992-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-30 | 1996-04-30 | 1996-10-30 | $7700.00 | Window Closed / Lapsed |