US4141746A
Expired / Lapsed
US
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Cellulose sulfate esters
Assignee: Individual
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Filing: 1977-04-11
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Granted: 1979-02-27
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Expires: 1997-04-11
Abstract
Abstract A water-soluble sulfate ester of cellulose having a degree of substitution of about 0.3 to about 1.0 with a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose. A thickened aqueous medium containing water and said water-soluble sulfate ester of cellulose having a degree of substitution of about 0.3 to about 1.0. A water-insoluble sulfate ester of cellulose which is highly swellable in the presence of water and has a degree of substitution of up to about 0.3 with the sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose. A water-soluble colloidal cellulose sulfate ester having a degree of substitution of about 1.3 to about 2 with the sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose. A thickened aqueous medium containing water and said water-soluble cellulose sulfate ester having a degree of substitution of about 1.3 to about 2.0. A water-soluble colloidal cellulose sulfate ester having a degree of substitution of about 1.0 to about 1.3 with the sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose. A thickened aqueous medium containing water and said water-soluble sulfate ester having a degree of substitution of about 1.0 to about 1.3.
Inventors
- 👤 Richard G. Schweiger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:31
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/34; C08F8/36; C08B; C08B31/00; C08B31/02; C08B31/06; C08B37/00; C08B5/00; C08B5/02; C08B5/14; C08F8/30; C08F8/42
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
97 words
a water-insoluble sulfate ester of cellulose which is swellable in the presence of water; said sulfate ester being prepared by reacting a nitrite ester of cellulose with sulfur trioxide or a complex thereof at a reaction temperature of about 0° to about 25° C. to obtain a reaction product and reacting said reaction product with a protic solvent to remove residual nitrite ester groups from the reaction product; said sulfate ester having a degree of substitution of up to about 0.3, and said sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose.
Claim 2
Dependent Claim
97 words
a water-insoluble sulfate ester of cellulose which is swellable in the presence of water; said sulfate ester being prepared by reacting a nitrite ester of cellulose with sulfur trioxide or a complex thereof at a reaction temperature of about 0° to about 25° C. to obtain a reaction product and reacting said reaction product with a protic solvent to remove residual nitrite ester groups from the reaction product; said sulfate ester having a degree of substitution of up to about 0.3, and said sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose.
Claim 3
Dependent Claim
177 words
A water-soluble colloidal sulfate ester of cellulose having a degree of substitution of about 0.3 to about 1.0; said sulfate ester having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose, and said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + , Sn ++ , Ba ++ , Fe +++ and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight.
Claim 4
Dependent Claim
177 words
A water-soluble colloidal sulfate ester of cellulose having a degree of substitution of about 0.3 to about 1.0; said sulfate ester having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose, and said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + , Sn ++ , Ba ++ , Fe +++ and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight.
Claim 5
Dependent Claim
14 words
The metal salts of the sulfate esters of cellulose as defined in claim 2.
Claim 6
Dependent Claim
200 words
A thickened aqueous medium containing water and a water-soluble sulfate ester of cellulose; said sulfate ester having a degree of substitution of about 0.3 to about 1.0; said sulfate ester having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose; said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + , Sn ++ , Ba ++ , Fe +++ and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight, and said sulfate ester being present in an effective amount to thicken said aqueous medium.
Claim 7
Dependent Claim
200 words
A thickened aqueous medium containing water and a water-soluble sulfate ester of cellulose; said sulfate ester having a degree of substitution of about 0.3 to about 1.0; said sulfate ester having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose; said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + , Sn ++ , Ba ++ , Fe +++ and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight, and said sulfate ester being present in an effective amount to thicken said aqueous medium.
Claim 8
Dependent Claim
178 words
A water soluble colloidal cellulose sulfate ester having a degree of substitution of about 1.0 to about 1.3; said sulfate ester having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose, and said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + , Sn ++ , Ba ++ , Fe +++ , and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight.
Claim 9
Dependent Claim
178 words
A water soluble colloidal cellulose sulfate ester having a degree of substitution of about 1.0 to about 1.3; said sulfate ester having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose, and said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + , Sn ++ , Ba ++ , Fe +++ , and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight.
Claim 10
Dependent Claim
13 words
The metal salts of the cellulose sulfate esters as defined in claim 5.
Claim 11
Dependent Claim
191 words
A thickened aqueous medium containing water and a water-soluble cellulose sulfate ester; said ester having a degree of substitution of about 1.0 to about 1.3; said ester having a uniform distribution of sulfate ester groups among the polymer units of the cellulose; said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Ag + , Sn ++ , Ba ++ , Fe +++ and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight, and said water-soluble cellulose sulfate ester being present in an effective amount to thicken said aqueous medium.
Claim 12
Dependent Claim
191 words
A thickened aqueous medium containing water and a water-soluble cellulose sulfate ester; said ester having a degree of substitution of about 1.0 to about 1.3; said ester having a uniform distribution of sulfate ester groups among the polymer units of the cellulose; said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Ag + , Sn ++ , Ba ++ , Fe +++ and Ce +++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight, and said water-soluble cellulose sulfate ester being present in an effective amount to thicken said aqueous medium.
Claim 13
Dependent Claim
19 words
The composition of claim 7 wherein said cellulose sulfate ester is present in the form of a metal salt.
Claim 14
Dependent Claim
161 words
A water-soluble colloidal cellulose sulfate ester having a degree of substitution of about 1.3 to about 2; said sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose, and said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Ag + and Sn ++ ions when a volume of a one percent mixture by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight.
Claim 15
Dependent Claim
161 words
A water-soluble colloidal cellulose sulfate ester having a degree of substitution of about 1.3 to about 2; said sulfate ester groups being substantially uniformly distributed among the polymer units of the cellulose, and said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Ag + and Sn ++ ions when a volume of a one percent mixture by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentration in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentration is less than 20 percent by weight.
Claim 16
Dependent Claim
13 words
The metal salts of the cellulose sulfate esters as defined in claim 9.
Claim 17
Dependent Claim
174 words
A thickened aqueous medium containing water and a water-soluble cellulose sulfate ester; said sulfate ester having a degree of substitution of about 1.3 to about 2.0; said sulfate having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose; said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + and Sn ++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentraton in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentraton is less than 20 percent by weight.
Claim 18
Dependent Claim
174 words
A thickened aqueous medium containing water and a water-soluble cellulose sulfate ester; said sulfate ester having a degree of substitution of about 1.3 to about 2.0; said sulfate having a substantially uniform distribution of sulfate ester groups among the polymer units of the cellulose; said sulfate ester being compatible and non-gelable in an aqueous medium in the presence of NH 4 + , Na + , K + , Mg ++ , Ca ++ , Al +++ , Zn ++ , Ni ++ , Co ++ , Cu ++ , Cd ++ , Fe ++ , Cr +++ , Pb ++ , Hg ++ , Ag + and Sn ++ ions when a volume of a one percent by weight aqueous solution of said ester is admixed with an equal volume of a solution of a salt containing one of said ions with said salt having a concentraton in the salt solution of either 20 percent by weight or the salt saturation concentration when the saturation concentraton is less than 20 percent by weight.
Claim 19
Dependent Claim
19 words
The composition of claim 11 wherein said cellulose sulfate ester is present in the form of a metal salt.
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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) | 1982-02-26 | 1982-08-28 | 1983-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-26 | 1986-08-28 | 1987-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-26 | 1990-08-28 | 1991-02-27 | $7700.00 | Window Closed / Lapsed |