Patent US3791526A successfully refreshed from Google Patents.
US3791526A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solvent weld adhesive for reverse osmosis membranes
Assignee: Graftech Technology LLC
•
Filing: 1971-08-10
•
Granted: 1974-02-12
•
Expires: 1991-08-10
Abstract
Abstract A method of sealing a reverse osmosis membrane to a contacting porous support comprises applying a sealant composition, comprising a cellulose ester, an organic solvent and an alcohol to the membrane and its contacting support.
Inventors
- 👤 R Stana
- 👤 E Mitchell
- 👤 J Coffay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:56
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/02; B01D61/08; B01D63/00; B01D63/06; B01D63/061; B01D2313/00; B01D2313/04; B01D2313/042
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
14 words
about 55 to 70 wt. percent organic solvent capable of dissolving cellulose esters, and
Claim 2
Dependent Claim
33 words
The reverse osmosis apparatus of claim 1 wherein the porous support is a module having a flat end face and at least one bore therethrough containing therein a tubular semipermeable cellulose ester membrane.
Claim 3
Dependent Claim
63 words
about 16 to 35 wt. percent of a low carbon chain alkanol and wherein the weight ratio of organic solvent:alkanol is between 5:1 to 2:1, said composition having a post gelation shrinkage of up to about 4 percent, d. means to supply feed liquid to the apparatus, e. means to exhaust feed liquid from the apparatus, and f. means to collect the permeate.
Claim 4
Dependent Claim
76 words
The reverse osmosis apparatus of claim 2 wherein the filler making up the module is sand having an average particle size between about 40 and 500 microns, the resin bonding said particles together comprising from about 1 to 18 percent of the coated filler particle weight, the resin being selected from the group consisting of phenolics, polyglycidylethers, polyesters, silicones, polystyrenes, polyimides, polyamide-imides, allyl resins and furane resins and the membrane is a modified cellulose acetate membrane.
Claim 5
Dependent Claim
78 words
The reverse osmosis apparatus of claim 2 where, in the sealant composition, the alkanol is selected from the group consisting of methanol, ethanol, n-propanol, isopropanol and butanol and the organic solvent is selected from the group consisting of aliphatic ketones and esters of aliphatic acids and wherein the flat end faces of the support module are sealed with the sealant composition to fill the pores between the resin coated filler particles to provide a liquid impermeable end face.
References Cited (Backward Citations)
US3138509A
Cited
US3156608A
Cited
US3285765A
Cited
US3619459A
Cited
US3645938A
Cited
US3610418A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |