US4210489A
Expired / Lapsed
US
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Method of imparting wet strength to paper products
Assignee: WR Grace and Co
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Filing: 1978-06-21
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Granted: 1980-07-01
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Expires: 1998-06-21
Abstract
Abstract The present invention relates to a method of forming paper webs having high wet strength and water absorbency by impregnating cellulose fibrous material with an aqueous composition made from a mixture of copolymers comprising an effective amount of (A) a hydrolyzed product of a copolymer having the general formula: <IMAGE> wherein R, R', R'', and R''' are each of C1-C4 alkyl group; A is a quarternary ammonium anion; y has a value of 0 to 1; and a is an integer and b and c are each integers including zero such that the ratio of a to b plus c is from about 2:1 to 1:2 and (B) a reaction product of a secondary alkylamine with a primary amine and with an epihalohydrin.
Inventors
- 👤 Sheldon B. Markofsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:20
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/54; D21H17/34; D21H17/41; D21H17/42; D21H17/43; D21H17/44; D21H17/45; D21H17/455
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
235 words
A method of imparting a combination of wet strength and water absorbency to paper formed from cellulosic fibers comprising contacting the cellulosic fibers with an aqueous solution of a composition comprising an effective amount to impart wet strength and water absorbency of (1) a copolymer selected from an at least partially hydrolyzed ethylene/maleic anhydride or an ethylene/maleic anhydride half ester, having the general formula: ##STR3## wherein R, R', R", and R'" are each of C 1 -C 4 alkyl or alkoxy groups; A is a quarternary anion; Y has a value of 0 to 1 and a is an integer, and b and c are integers including 0, such that the ratio of a to b plus c is 2:1 to 1:2, and (2) a reaction product formed by reacting an aqueous mixture of reactants (a) a C 2 -C 12 secondary alkyl amine; (b) a C 1 -C 25 primary amine and (c) a member selected from epihalohydrin or a dihalo monohydroxy C 3 -C 4 alkane; the equivalent ratio of reactant (c) to (b) is 1:0.009 to 0.5, and of reactants (c) to (b) plus (a) is 1:0.22 to 1.3, and the weight ratio of reaction product (2) to copolymer (1) being from about 0.2:1 to 50:1 and treating the paper formed from said cellulosic fibers to sufficient elevated temperature to cause drying of the paper product and curing of the agents therein.
Claim 2
Independent Claim
235 words
A method of imparting a combination of wet strength and water absorbency to paper formed from cellulosic fibers comprising contacting the cellulosic fibers with an aqueous solution of a composition comprising an effective amount to impart wet strength and water absorbency of (1) a copolymer selected from an at least partially hydrolyzed ethylene/maleic anhydride or an ethylene/maleic anhydride half ester, having the general formula: ##STR3## wherein R, R', R", and R'" are each of C 1 -C 4 alkyl or alkoxy groups; A is a quarternary anion; Y has a value of 0 to 1 and a is an integer, and b and c are integers including 0, such that the ratio of a to b plus c is 2:1 to 1:2, and (2) a reaction product formed by reacting an aqueous mixture of reactants (a) a C 2 -C 12 secondary alkyl amine; (b) a C 1 -C 25 primary amine and (c) a member selected from epihalohydrin or a dihalo monohydroxy C 3 -C 4 alkane; the equivalent ratio of reactant (c) to (b) is 1:0.009 to 0.5, and of reactants (c) to (b) plus (a) is 1:0.22 to 1.3, and the weight ratio of reaction product (2) to copolymer (1) being from about 0.2:1 to 50:1 and treating the paper formed from said cellulosic fibers to sufficient elevated temperature to cause drying of the paper product and curing of the agents therein.
Claim 3
Dependent Claim
42 words
The method according to claim 1 wherein the cellulosic fiber is contacted with the aqueous wet strength composition prior to the formation of a web therefrom and the treated web is subjected to a temperature of from about 90° to 150° C.
Claim 4
Dependent Claim
42 words
The method according to claim 1 wherein the cellulosic fiber is contacted with the aqueous wet strength composition subsequent to the formation of the web therefrom and the treated web is subjected to a temperature of from about 90° to 150° C.
Claim 5
Dependent Claim
24 words
The method according to claim 2 or 3 wherein the ratio of b to c in copolymer (1) is from about 0.1:1 to 1:1.
Claim 6
Dependent Claim
23 words
The method according to claim 2 or 3 wherein the ratio of b to c in copolymer (1) is at least about 0.25:1.
Claim 7
Dependent Claim
20 words
The method according to claim 1 wherein copolymer (1) has an average molecular weight ranging from about 5,000 to 250,000.
Claim 8
Dependent Claim
21 words
The method according to claim 6 wherein the copolymer (1) has an average molecular weight ranging from about 50,000 to 100,000.
Claim 9
Dependent Claim
194 words
A paper product capable of exhibiting high wet strength and water absorbency having impregnated therein from about 0.1 to 5 percent by weight of the dry paper of the composition comprising (1) a copolymer selected from an at least partially hydrolyzed ethylene/maleic anhydride or an ethylene/maleic anhydride half ester, having the general formula: ##STR4## wherein R, R', R", and R'" are each of C 1 -C 4 alkyl or alkoxy groups; A is a quarternary anion; Y has a value of 0 to 1; and a is an integer, and b and c are integers including 0, such that the ratio of a to b plus c is 2:1 to 1:2, and (2) a reaction product formed by reacting an aqueous mixture of reactants (a) a C 2 -C 12 secondary alkyl amine; (b) a primary amine and (c) a member selected from epihalohydrin or a dihalo monohydroxy C 3 -C 4 alkane; the equivalent ratio of reactant (c) to (b) is 1:0.009 to 0.5 and of reactants (c) to (b) plus (a) is 1:0.22 to 1.3, and the weight ratio of reaction product (2) to copolymer (1) being from about 0.2:1 to 50:1.
Claim 10
Dependent Claim
194 words
A paper product capable of exhibiting high wet strength and water absorbency having impregnated therein from about 0.1 to 5 percent by weight of the dry paper of the composition comprising (1) a copolymer selected from an at least partially hydrolyzed ethylene/maleic anhydride or an ethylene/maleic anhydride half ester, having the general formula: ##STR4## wherein R, R', R", and R'" are each of C 1 -C 4 alkyl or alkoxy groups; A is a quarternary anion; Y has a value of 0 to 1; and a is an integer, and b and c are integers including 0, such that the ratio of a to b plus c is 2:1 to 1:2, and (2) a reaction product formed by reacting an aqueous mixture of reactants (a) a C 2 -C 12 secondary alkyl amine; (b) a primary amine and (c) a member selected from epihalohydrin or a dihalo monohydroxy C 3 -C 4 alkane; the equivalent ratio of reactant (c) to (b) is 1:0.009 to 0.5 and of reactants (c) to (b) plus (a) is 1:0.22 to 1.3, and the weight ratio of reaction product (2) to copolymer (1) being from about 0.2:1 to 50:1.
Claim 11
Dependent Claim
22 words
The paper product of claim 8 wherein the ratio of b to c in copolymer (1) is from about 0.1:1 to 1:1.
Claim 12
Dependent Claim
37 words
The composition of claim 9 wherein copolymer (1) has an average molecular weight ranging from about 5,000 to 250,000 and reaction product (2) is formed from a ratio from reactants (a) to (b) of at least 1:1.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-07-01 | 1983-12-31 | 1984-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-01 | 1987-12-31 | 1988-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-01 | 1991-12-31 | 1992-07-01 | $7700.00 | Window Closed / Lapsed |