Patent US4290812A successfully refreshed from Google Patents.
US4290812A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of inks free of foreign salts
Assignee: AEG Olympia Office GmbH
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Filing: 1980-07-28
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Granted: 1981-09-22
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Expires: 2000-07-28
Abstract
Abstract A method for the production of an ink suitable for use in ink-jet printing, free from foreign salts, made from technical dyes. A highly water-soluble dye is dissolved in water and precipitated with a precipitant amine. The precipitate is separated from the solution and distilled with water and a water-soluble amine of low volatility to convert the dye back to a soluble form.
Inventors
- 👤 Ehrenfried Loock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:10
CPC Classifications
C; C09; C09D; C09D11/00; C09D11/30; C09D11/16
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
103 words
A process for the production of an ink, free from foreign salts, from a technical anionic dye, comprising: (a) dissolving at least one highly water-soluble dye in water to form an aqueous solution; (b) precipitating the dye from this aqueous solution by adding a precipitant organic amine to form an insoluble precipitated dye; (c) separating said precipitated dye from said solution; (d) converting said precipitated dye into a highly water-soluble form by distillation in the presence of water and a water-soluble amine of low volatility; and (e) dissolving the water-soluble dye obtained in step (d) in a solvent to obtain a dye solution.
Claim 2
Dependent Claim
103 words
A process for the production of an ink, free from foreign salts, from a technical anionic dye, comprising: (a) dissolving at least one highly water-soluble dye in water to form an aqueous solution; (b) precipitating the dye from this aqueous solution by adding a precipitant organic amine to form an insoluble precipitated dye; (c) separating said precipitated dye from said solution; (d) converting said precipitated dye into a highly water-soluble form by distillation in the presence of water and a water-soluble amine of low volatility; and (e) dissolving the water-soluble dye obtained in step (d) in a solvent to obtain a dye solution.
Claim 3
Dependent Claim
15 words
Process according to claim 1 wherein said anionic dye is a sulfonic acid sodium salt.
Claim 4
Dependent Claim
14 words
Process according to claim 1 wherein said anionic dye is an azo type dye.
Claim 5
Dependent Claim
16 words
Process according to claim 1 wherein said precipitant amine is a compound of cyclohexylamine or dicyclohexylamine.
Claim 6
Dependent Claim
14 words
Process according to claim 4 wherein said compound is cyclohexylamine citrate or dicyclohexylamine citrate.
Claim 7
Dependent Claim
29 words
Process according to claim 5 wherein said compound is added in an aqueous solution of about 20% by weight concentration with a pH adjusted to about 4 to 6.
Claim 8
Dependent Claim
12 words
Process according to claim 1 wherein said separation takes place by filtration.
Claim 9
Dependent Claim
13 words
Process according to claim 7 wherein said filtration takes place by vacuum filtration.
Claim 10
Dependent Claim
14 words
Process according to claim 1 wherein said water-soluble amine of low volatility is diethanolamine.
Claim 11
Dependent Claim
12 words
Process according to claim 9 wherein said distillation takes place under vacuum.
Claim 12
Dependent Claim
15 words
Process according to claim 10 wherein said vacuum distillation takes place at about 70° C.
Claim 13
Dependent Claim
15 words
Process according to claim 9 wherein the weight ratio of precipitated dye:diethanolamine:water is about 1:2:10.
Claim 14
Dependent Claim
10 words
Process according to claim 1 wherein said solvent comprises water.
Claim 15
Dependent Claim
20 words
Process according to claim 1 comprising in step (a) dissolving said dye while the water is at an elevated temperature.
Claim 16
Dependent Claim
40 words
Process according to claim 1 wherein 10 grams of dye is dissolved in 100 ml water, an aqueous weakly acidic dicyclohexylamine citrate solution is added to completely precipitate the dye, and the precipitate is vacuum filtered and washed with water.
Claim 17
Dependent Claim
18 words
Process according to claim 15 additionally comprising dissolving said dye while the water is at an elevated temperature.
Claim 18
Dependent Claim
29 words
Process according to claim 15 wherein the dicyclohexylamine citrate solution has a concentration of about 20% by weight and is adjusted to a pH of about 4 to 6.
Claim 19
Dependent Claim
38 words
Process according to claim 1, wherein 20 grams of dye is mixed with 100 ml water, the precipitation is conducted with an aqueous weakly acidic, cyclohexylamine citrate solution and the precipitate is vacuum filtered and washed with water.
Claim 20
Dependent Claim
21 words
Process according to claim 18 wherein comprising in step (a) mixing the dye with water which is at an elevated temperature.
Claim 21
Dependent Claim
27 words
Process according to claim 18 wherein said cyclohexylamine citrate solution has a concentration of about 20% by weight and is adjusted to a pH of about 6.
Claim 22
Dependent Claim
41 words
Process according to claim 4, wherein said precipitated dye is converted to a water-soluble form by mixing with diethanolamine and water in a dye:diethanolamine:water weight ratio of about 1:2:10, and distilling the mixture under vacuum to remove the cyclohexylamine or dicyclohexylamine.
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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) | 1984-09-21 | 1985-03-23 | 1985-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-21 | 1989-03-23 | 1989-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-21 | 1993-03-23 | 1993-09-22 | $7700.00 | Window Closed / Lapsed |