US5247072A
Expired / Lapsed
US
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Carboxyalkyl polysaccharides having improved absorbent properties and process for the preparation thereof
Assignee: Kimberly Clark Worldwide Inc
•
Filing: 1992-09-28
•
Granted: 1993-09-21
•
Expires: 2012-09-28
Abstract
Abstract Disclosed is a method for producing a water-swellable, generally water-insoluble, carboxyalkyl polysaccharide having improved absorption properties. The method involves forming a solution of carboxyalkyl polysaccharide and water, recovering the carboxyalkyl polysaccharide from the solution and heat-treating said recovered carboxyalkyl polysaccharide. Also, described is a carboxyalkyl polysaccharide having improved absorption properties.
Inventors
- 👤 Xin Ning
- 👤 Tong Sun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:01
CPC Classifications
C; C08; C08B; C08B15/00; C08B15/005; A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; C08B11/00; C08B11/02; C08B11/04; C08B11/10; C08B11/12; C08B11/20
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
73 words
A method for producing a water-swellable, water-insoluble carboxyalkyl polysaccharide, said method comprising the following steps: forming a solution comprising a water-soluble carboxyalkyl polysaccharide and water, said carboxyalkyl polysaccharide having an average degree of substitution from about 0.3 to about 1.5; recovering said carboxyalkyl polysaccharide from said solution; and heat-treating said recovered carboxyalkyl polysaccharide at a temperature and for a time sufficient to crosslink said carboxyalkylpolysaccharide to render said carboxyalkyl polysaccharide generally water insoluble.
Claim 2
Independent Claim
73 words
A method for producing a water-swellable, water-insoluble carboxyalkyl polysaccharide, said method comprising the following steps: forming a solution comprising a water-soluble carboxyalkyl polysaccharide and water, said carboxyalkyl polysaccharide having an average degree of substitution from about 0.3 to about 1.5; recovering said carboxyalkyl polysaccharide from said solution; and heat-treating said recovered carboxyalkyl polysaccharide at a temperature and for a time sufficient to crosslink said carboxyalkylpolysaccharide to render said carboxyalkyl polysaccharide generally water insoluble.
Claim 3
Dependent Claim
14 words
The method according to claim 1 wherein the carboxyalkyl polysaccharide is a carboxyalkyl cellulose.
Claim 4
Dependent Claim
22 words
The method according to claim 2, wherein the solution comprises from about 0.01 to about 90 weight percent of said carboxyalkyl cellulose.
Claim 5
Dependent Claim
22 words
The method according to claim 2, wherein said carboxyalkyl cellulose has a degree of substitution of from about 0.4 to about 1.2.
Claim 6
Dependent Claim
24 words
The method according to claim 1, wherein said solution comprising said carboxyalkyl polysaccharide and water has a degree of acidification of less than 0.07.
Claim 7
Dependent Claim
20 words
The method according to claim 1, wherein said solution comprising said carboxyalkyl polysaccharide and water has a generally neutral pH.
Claim 8
Dependent Claim
13 words
The method according to claim 2, wherein said carboxyalkyl cellulose is carboxymethyl cellulose.
Claim 9
Dependent Claim
18 words
The method according to claim 1, wherein said carboxyalkyl polysaccharide is recovered from said solution by evaporative drying.
Claim 10
Dependent Claim
17 words
The method according to claim 1, wherein said carboxyalkyl polysaccharide is recovered from said solution by precipitation.
Claim 11
Dependent Claim
36 words
The method according to claim 2, wherein said recovered carboxyalkyl cellulose is heat-treated at a temperature and for a time sufficient to provide said carboxyalkyl cellulose with an Absorbency Under Load of at least about 17.
Claim 12
Dependent Claim
36 words
The method according to claim 2, wherein said recovered carboxyalkyl cellulose is heat-treated at a temperature and for a time sufficient to provide said carboxyalkyl cellulose with an Absorbency Under Load of at least about 24.
Claim 13
Dependent Claim
36 words
The method according to claim 2, wherein said recovered carboxyalkyl cellulose is heat-treated at a temperature and for a time sufficient to provide said carboxyalkyl cellulose with an Absorbency Under Load of at least about 27.
Claim 14
Dependent Claim
36 words
The method according to claim 10, wherein said carboxyalkyl cellulose is heat-treated at a temperature of from about 120° C. to about 200° C. for a time of from about 1 minute to about 120 minutes.
Claim 15
Dependent Claim
36 words
The method according to claim 13, wherein said carboxyalkyl cellulose is heat-treated at a temperature of from about 130° C. to about 170° C. for a time of from about 1 minute to about 120 minutes.
Claim 16
Dependent Claim
36 words
The method according to claim 14, wherein said carboxyalkyl cellulose is heat-treated at a temperature of from about 130° C. to about 170° C. for a time of from about 5 minutes to about 60 minutes.
Claim 17
Dependent Claim
20 words
The method according to claim 1, further comprising the step of comminuting said carboxyalkyl polysaccharide after recovery and before heat-treating.
Claim 18
Independent Claim
114 words
A method for producing a water-swellable, generally water-insoluble carboxyalkyl polysaccharide, said method comprising the following sequential steps: forming a solution comprising from about 0.01 to about 90 weight percent of a water-soluble carboxyalkyl polysaccharide, based on total solution weight and water, said carboxyalkyl polysaccharide having an average degree of substitution of from about 0.4 to about 1.2; recovering said carboxyalkyl polysaccharide from said solution; and heat-treating said recovered carboxyalkyl polysaccharide at a temperature of from about 100° C. to about 250° C. for a time of from about 1 minute to about 600 minutes, such that said carboxyalkyl polysaccharide is rendered generally water-insoluble and has an Absorbency Under Load of at least about 17.
Claim 19
Independent Claim
114 words
A method for producing a water-swellable, generally water-insoluble carboxyalkyl polysaccharide, said method comprising the following sequential steps: forming a solution comprising from about 0.01 to about 90 weight percent of a water-soluble carboxyalkyl polysaccharide, based on total solution weight and water, said carboxyalkyl polysaccharide having an average degree of substitution of from about 0.4 to about 1.2; recovering said carboxyalkyl polysaccharide from said solution; and heat-treating said recovered carboxyalkyl polysaccharide at a temperature of from about 100° C. to about 250° C. for a time of from about 1 minute to about 600 minutes, such that said carboxyalkyl polysaccharide is rendered generally water-insoluble and has an Absorbency Under Load of at least about 17.
Claim 20
Dependent Claim
14 words
The method according to claim 17 wherein the carboxyalkyl polysaccharide is a carboxyalkyl cellulose.
Claim 21
Dependent Claim
10 words
A carboxyalkyl polysaccharide produced by the method of claim 1.
Claim 22
Dependent Claim
10 words
A carboxyalkyl polysaccharide produced by the method of claim 17.
Claim 23
Dependent Claim
10 words
A carboxyalkyl cellulose produced by the method of claim 18.
Claim 24
Dependent Claim
44 words
A water-swellable, generally water-insoluble, carboxyalkyl polysaccharide characterized in that said carboxyalkyl polysaccharide has an average degree of substitution from about 0.3 to about 1.5 and has an Absorbency Under Load of at least about 17 and a Free-Swell Capacity of at least about 20.
Claim 25
Dependent Claim
44 words
A water-swellable, generally water-insoluble, carboxyalkyl polysaccharide characterized in that said carboxyalkyl polysaccharide has an average degree of substitution from about 0.3 to about 1.5 and has an Absorbency Under Load of at least about 17 and a Free-Swell Capacity of at least about 20.
Claim 26
Dependent Claim
21 words
The carboxyalkyl polysaccharide according to claim 22, wherein said carboxyalkyl polysaccharide has an Absorbency Under Load of at least about 20.
Claim 27
Dependent Claim
21 words
The carboxyalkyl polysaccharide according to claim 22, wherein said carboxyalkyl polysaccharide has an Absorbency Under Load of at least about 24.
Claim 28
Dependent Claim
21 words
The carboxyalkyl polysaccharide according to claim 22, wherein said carboxyalkyl polysaccharide has an Absorbency Under Load of at least about 27.
Claim 29
Dependent Claim
21 words
The carboxyalkyl polysaccharide according to claim 22, wherein said carboxyalkyl polysaccharide has a Degree of Molar Acidification of less than 0.07.
Claim 30
Dependent Claim
14 words
The carboxyalkyl polysaccharide according to claim 22, wherein said carboxyalkyl polysaccharide is generally neutral.
Claim 31
Dependent Claim
14 words
The carboxyalkyl polysaccharide according to claim 22, wherein said carboxyalkyl polysaccharide is carboxyalkyl cellulose.
Claim 32
Dependent Claim
14 words
The carboxyalkyl cellulose according to claim 28, wherein said carboxyalkyl cellulose is carboxymethyl cellulose.
Claim 33
Dependent Claim
14 words
The carboxyalkyl polysaccharide according to claim 25, wherein said carboxyalkyl polysaccharide is carboxymethyl cellulose.
Claim 34
Dependent Claim
20 words
The carboxyalkyl cellulose according to claim 28, wherein said carboxyalkyl cellulose has a Free-Swell Capacity of at least about 30.
Claim 35
Dependent Claim
20 words
The carboxyalkyl Cellulose according to claim 28, wherein said carboxyalkyl cellulose has a Free-Swell Capacity of at least about 35.
Claim 36
Dependent Claim
18 words
The carboxyalkyl polysaccharide according to claim 22, wherein said carboxyalkyl polysaccharide is in the form of discrete particles.
Claim 37
Dependent Claim
44 words
A water-swellable, generally water-insoluble, carboxyalkyl polysaccharide characterized in that said carboxyalkyl polysaccharide has an average degree of substitution from about 0.4 to about 1.2 and has an Absorbency Under Load of at least about 20 and a Free-Swell Capacity of at least about 20.
Claim 38
Dependent Claim
44 words
A water-swellable, generally water-insoluble, carboxyalkyl polysaccharide characterized in that said carboxyalkyl polysaccharide has an average degree of substitution from about 0.4 to about 1.2 and has an Absorbency Under Load of at least about 20 and a Free-Swell Capacity of at least about 20.
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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) | 1996-09-20 | 1997-03-22 | 1997-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-20 | 2001-03-22 | 2001-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-20 | 2005-03-22 | 2005-09-21 | $7700.00 | Window Closed / Lapsed |