EP0538904A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Carboxyalkyl polysaccharides and process for their preparation
Assignee: Kimberly Clark Worldwide Inc
•
Filing: 1992-10-26
•
Granted: —
•
Expires: 2012-10-26
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. <IMAGE>
Inventors
- 👤 Xin Ning
- 👤 Tong Sun
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 17:05
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: 35
Claim 1
Independent Claim
72 words
A method for producing a water-swellable, water-insoluble carboxyalkyl polysaccharide, characterized by 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
Dependent Claim
14 words
The method according to claim 1 wherein the carboxyalkyl polysaccharide is a carboxyalkyl cellulose.
Claim 3
Dependent Claim
24 words
The method according to claim 1 or 2, wherein the solution comprises from about 0.01 to about 90 weight percent of said carboxyalkyl polysaccharide.
Claim 4
Dependent Claim
24 words
The method according to claim 2 or 3, wherein said carboxyalkyl cellulose has a degree of substitution of from about 0.4 to about 1.2.
Claim 5
Independent Claim
28 words
The method according to any of claims 1 to 4, wherein said solution comprising said carboxyalkyl polysaccharide and water has a degree of acidification of less than 0.07.
Claim 6
Independent Claim
24 words
The method according to any of claims 1 to 5, wherein said solution comprising said carboxyalkyl polysaccharide and water has a generally neutral pH.
Claim 7
Independent Claim
21 words
The method according to any of claims 1 to 5, wherein said solution comprising said carboxyalkyl polysaccharide and water is basic.
Claim 8
Dependent Claim
21 words
The method according to any of claims 1 to 7, particularly of claim 2, wherein said carboxyalkyl cellulose is carboxymethyl cellulose.
Claim 9
Independent Claim
22 words
The method according to any of claims 1 to 8, wherein said carboxyalkyl polysaccharide is recovered from said solution by evaporative drying.
Claim 10
Independent Claim
21 words
The method according to any of claims 1 to 8, wherein said carboxyalkyl polysaccharide is recovered from said solution by precipitation.
Claim 11
Dependent Claim
44 words
The method according to any of claims 2 to 10, particularly of 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
16 words
The method according to claim 11, wherein said Absorbency Under Load is at least about 24.
Claim 13
Dependent Claim
16 words
The method according to claim 11, wherein said Absorbency Under Load is at least about 27.
Claim 14
Independent Claim
38 words
The method according to any of claims 11 to 13, 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 min. to about 120 mins.
Claim 15
Dependent Claim
34 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 1 min. to about 120 min.
Claim 16
Dependent Claim
34 words
The method according to claim 15, 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 min. to about 60 min.
Claim 17
Independent Claim
24 words
The method according to any of claims 1 to 16, further comprising the step of comminuting said carboxyalkyl polysaccharide after recovery and before heat-treating.
Claim 18
Independent Claim
112 words
A method for producing a water-swellable, generally water-insoluble carboxyalkyl polysaccharide, charactirized by 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 min. to about 600 min. , such that said carboxyalkyl polysaccharide is rendered generally water-insoluble and has an Absorbency Under Load of at least about 17.
Claim 19
Dependent Claim
14 words
The method according to claim 18 wherein the carboxyalkyl polysaccharide is a carboxyalkyl cellulose.
Claim 20
Dependent Claim
21 words
A carboxyalkyl polysaccharide produced by the method of any of claims 1 to 19, particularly of claims 1, 18 and 19.
Claim 21
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 22
Dependent Claim
21 words
The carboxyalkyl polysaccharide according to claim 21, wherein said carboxyalkyl polysaccharide has an Absorbency Under Load of at least about 20.
Claim 23
Dependent Claim
21 words
The carboxyalkyl polysaccharide according to claim 21, wherein said carboxyalkyl polysaccharide has an Absorbency Under Load of at least about 24.
Claim 24
Dependent Claim
21 words
The carboxyalkyl polysaccharide according to claim 21, wherein said carboxyalkyl polysaccharide has an Absorbency Under Load of at least about 27.
Claim 25
Dependent Claim
25 words
The carboxyalkyl polysaccharide according to any of claims 21 to 24, wherein said carboxyalkyl polysaccharide has a Degree of Molar Acidification of less than 0.07.
Claim 26
Dependent Claim
18 words
The carboxyalkyl polysaccharide according to any of claims 21 to 25, wherein said carboxyalkyl polysaccharide is generally neutral.
Claim 27
Dependent Claim
17 words
The carboxyalkyl polysaccharide according to any of claims 21 to 25, wherein said carboxyalkyl polysaccharide is basic.
Claim 28
Dependent Claim
18 words
The carboxyalkyl polysaccharide according to any of claims 21 to 27, wherein said carboxyalkyl polysaccharide is carboxyalkyl cellulose.
Claim 29
Dependent Claim
14 words
The carboxyalkyl cellulose according to claim 28, wherein said carboxyalkyl cellulose is carboxymethyl cellulose.
Claim 30
Dependent Claim
14 words
The carboxyalkyl polysaccharide according to claim 24, wherein said carboxyalkyl polysaccharide is carboxymethyl cellulose.
Claim 31
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 32
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 33
Dependent Claim
22 words
The carboxyalkyl polysaccharide according to any of claims 21 to 32, wherein said carboxyalkyl polysaccharide is in the form of discrete particles.
Claim 34
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 35
Dependent Claim
17 words
Use of a carboxyalkyl polysaccharide according to any of claims 20 to 34 for producing absorbent products.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.