US3873518A
Expired / Lapsed
US
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Water soluble ternary cellulose ethers
Assignee: Dow Chemical Co
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Filing: 1973-12-14
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Granted: 1975-03-25
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Expires: 1993-12-14
Abstract
Abstract Novel water soluble ternary cellulose ethers are prepared by reacting alkali cellulose with methyl chloride, propylene oxide, and ethylene oxide to give a hydroxyethyl hydroxypropyl methyl cellulose having a total degree of substitution greater than about 1.5 and a controlled gel point above 70*C. Because of excellent pigment color compatibility and enzyme resistance, these ternary cellulose ethers are particularly desirable as latex paint thickeners. Also their organic solubility makes these ethers useful in well-treating formulations.
Inventors
- 👤 Carl P Strange
- 👤 Robert T Sylvest
- 👤 Jr Joseph G Schell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:00
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C08; C08B; C08B11/00; C08B11/193; C09D; C09D7/00; C09D7/40; C09D7/43; C08L; C08L1/00; C08L1/08; C08L1/26; C08L1/28; C08L1/284
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
50 words
A WATER SOLUBLE HYDROXYETHYL HYDROXYPROPYL METHYL CELLULOSE HAVING A TOTAL DEGREE OF SUBSTITUTION GREATER THAN ABOUT 1.5, A METHOXYL CONTENT OF ABOUT 6-25.5 WT. %, A HYDROXYPROPOXYL CONTENT OF ABOUT 14-32 WT. %, A HYDROXYETHOXYL CONTENT OF ABOUT 10-22 WT. %, AND A THERMAL GEL POINT GREATER THAN ABOUT 70*C.
Claim 2
Dependent Claim
50 words
A WATER SOLUBLE HYDROXYETHYL HYDROXYPROPYL METHYL CELLULOSE HAVING A TOTAL DEGREE OF SUBSTITUTION GREATER THAN ABOUT 1.5, A METHOXYL CONTENT OF ABOUT 6-25.5 WT. %, A HYDROXYPROPOXYL CONTENT OF ABOUT 14-32 WT. %, A HYDROXYETHOXYL CONTENT OF ABOUT 10-22 WT. %, AND A THERMAL GEL POINT GREATER THAN ABOUT 70*C.
Claim 3
Dependent Claim
16 words
The ternary cellulose ether of claim 1 where the methoxyl substitution is about 6.5-11.0 wt. %.
Claim 4
Dependent Claim
16 words
The ternary cellulose ether of claim 1 where the hydroxypropoxyl substitution is about 14.5-27.5 wt. %.
Claim 5
Dependent Claim
16 words
The ternary cellulose ether of claim 1 where the hydroxyethoxyl substitution is about 15.0-22.0 wt. %.
Claim 6
Dependent Claim
28 words
The ternary cellulose ether of claim 1 having a thermal gel point of about 70*-90*C and a methanol solubility of at least 5 wt. % at room temperature.
Claim 7
Dependent Claim
19 words
The ternary cellulose ether of claim 1 having a 2% aqueous solution viscosity of about 400-100,000 cps at 20*C.
Claim 8
Dependent Claim
101 words
A process for preparing the water soluble ternary cellulose ether of claim 1 comprising: A. preparing an alkali cellulose by treating cellulose with about 0.35-0.75 parts NaOH/part cellulose using 35-70% aqueous NaOH; B. Blending the alkali cellulose in the absence of air with about 0.4-1.5 parts methyl chloride and about 0.75-2.0 parts propylene oxide per part cellulose and heating to about 40*-50*C; C. adding about 0.5-1.7 parts ethylene oxide per part cellulose over about 2-4 hours while maintaining a temperature of about 40*-60*C; and thereafter D. Recovering a solid ternary cellulose ether having a thermal gel point greater than about 70*C.
Claim 9
Dependent Claim
18 words
The process of claim 7 where the ethylene oxide is added incrementally at a temperature of about 45*-60*C.
Claim 10
Dependent Claim
25 words
The process of claim 7 where after the ethylene oxide addition is completed, the reaction mixture is heated at about 55*-80*C to complete the etherification.
Claim 11
Dependent Claim
22 words
The process of claim 7 where the recovered cellulose ether has a 2% aqueous solution viscosity of about 400-100,000 cps at 20*C.
Claim 12
Dependent Claim
46 words
An aqueous coating composition comprising an aqueous latex dispersion of finely divided, water insoluble polymer particles prepared from ethylenically unsaturated monomers, a pigment, and about 0.2-1.0 wt. % based on total solids weight of the coating composition of the water soluble ternary cellulose ether of claim
Claim 13
Dependent Claim
19 words
The aqueous coating composition of claim 11 where the methoxyl substitution of the ether is about 6.5-11.0 wt. %.
Claim 14
Dependent Claim
19 words
The aqueous coating composition of claim 11 where the hydroxypropoxyl substitution of the ether is about 14.5-27.5 wt. %.
Claim 15
Dependent Claim
19 words
The aqueous coating composition of claim 11 where the hydroxyethyl substitution of the ether is about 15.0-22.0 wt. %.
Claim 16
Dependent Claim
26 words
The aqueous coating composition of claim 11 where the total degree of substitution of the ether is about 1.7-2.7 and its thermal gel point about 70*-90*C.
Claim 17
Dependent Claim
45 words
The aqueous coating composition of claim 11 where the ternary cellulose ether has a methoxyl content of about 6.5-11.0 wt. %, a hydroxypropoxyl content of about 14.5-27.5 wt. %, a hydroxyethoxyl content of about 15.0-22.0 wt. %, and a thermal gel point of about 70*-90*C.
Claim 18
Dependent Claim
24 words
The aqueous coating composition of claim 15 where the ternary cellulose ether has a 2% aqueous solution viscosity of about 4,000-50,000 cps at 20*C.
Claim 19
Dependent Claim
16 words
The aqueous coating composition of claim 11 where the aqueous latex dispersion is a styrene-butadiene latex.
Claim 20
Dependent Claim
17 words
The aqueous coating composition of claim 11 where the aqueous latex dispersion is a polyvinyl acetate latex.
Claim 21
Dependent Claim
16 words
The aqueous coating composition of claim 11 where the aqueous latex dispersion is a polyacrylate latex.
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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) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |