US4765841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of an organic pigment dispersion
Assignee: Kemisk Vaerk Koge AS
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Filing: 1986-10-09
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Granted: 1988-08-23
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Expires: 2006-10-09
Abstract
Abstract An organic pigment dispersion in a non-aqueous medium is prepared directly from an aqueous slurry containing 0.1-20% by weight of the pigment by mixing the aqueous slurry with the non-aqueous medium under vigorous agitation and subsequently isolating the organic pigment dispersion from the residual aqueous phase. A substantial part of water in the resulting pigment dispersion can be removed by passing the organic pigment dispersion in the non-aqueous medium over a series of surfaces, the surface material thereof having different affinity for water and the non-aqueous medium, respectively, and then removing water and pigment dispersion in the non-aqueous medium, respectively, from respective surfaces.
Inventors
- 👤 Arne Vinther
- 👤 Steffen C. Olsen
- 👤 Bjorn E. H. Larsen
- 👤 Elun S. Madsen
- 👤 Bjorn Madsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:29
CPC Classifications
C; C09; C09D; C09D17/00; C09D17/003; C09B; C09B67/00; C09B67/0001; C09B67/0021
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
112 words
A process for the preparation of an organic pigment dispersion in a non-aqueous medium comprising the steps of: mixing an aqueous slurry of the organic pigment containing 0.1 to 10% by weight of the pigment, calculated on the slurry, in the presence of a dispersing agent component with the non-aqueous medium under vigorous agitation; isolating the organic pigment dispersion comprising up to 50% by weight of water from the residual aqueous phase; and removing a substantial proportion of the water contained in the organic pigment dispersion by contacting the dispersion with a surface with less affinity for water than for the non-aqueous medium and separating the aqueous phase from the non-aqueous phase.
Claim 2
Dependent Claim
112 words
A process for the preparation of an organic pigment dispersion in a non-aqueous medium comprising the steps of: mixing an aqueous slurry of the organic pigment containing 0.1 to 10% by weight of the pigment, calculated on the slurry, in the presence of a dispersing agent component with the non-aqueous medium under vigorous agitation; isolating the organic pigment dispersion comprising up to 50% by weight of water from the residual aqueous phase; and removing a substantial proportion of the water contained in the organic pigment dispersion by contacting the dispersion with a surface with less affinity for water than for the non-aqueous medium and separating the aqueous phase from the non-aqueous phase.
Claim 3
Dependent Claim
36 words
A process according to claim 1 wherein the resulting organic pigment dispersion, before the contacting with a surface with less affinity for water than for the non-aqueous medium, comprises up to 35% by weight of water.
Claim 4
Dependent Claim
36 words
A process according to claim 2 wherein the resulting organic pigment dispersion, before the contacting with a surface with less affinity for water than for the non-aqueous medium, comprises up to 15% by weight of water.
Claim 5
Dependent Claim
21 words
A process as claimed in claim 1 wherein the organic pigment constitutes 1 to 10% by weight of the aqueous slurry.
Claim 6
Dependent Claim
27 words
A process as claimed in claim 1 wherein the non-aqueous medium is an organic medium as normally used in the preparation of organic printing inks and paints.
Claim 7
Dependent Claim
18 words
A process as claimed in claim 5 wherein the organic medium is an organic solvent of low polarity.
Claim 8
Dependent Claim
41 words
A process as claimed in claim 5 wherein the organic medium comprises one or more organic solvents selected from the group consisting of liquids having a boiling point of at least 80° C. and in which the pigment is substantially insoluble.
Claim 9
Dependent Claim
31 words
A process as claimed in claim 5 wherein the organic medium is selected from the group consisting of aromatic and aliphatic optionally halogenated hydrocarbons, esters, alcohols, ketones, ethers, and mixtures thereof.
Claim 10
Dependent Claim
52 words
A process as claimed in claim 1 wherein the dispersing agent component is constituted of one or more agents selected from the group consisting of resins, alkyds and dispersants with a molecular structure which enables them to lock onto a selected pigment surface and furthermore contain a solvent soluble chain, so-called hyperdispersants.
Claim 11
Dependent Claim
79 words
A process as claimed in claim 9 wherein the dispersant is a derivative of a polyester derived from a hydroxy carboxylic acid of the formula HO--X--COOH wherein X is a divalent saturated or unsaturated radical containing at least 8 carbon atoms and in which there are at least 4 carbon atoms between the hydroxy and the carboxylic acid groups, or from a mixture of such a hydroxy carboxylic acid and a carboxylic acid which is free from hydroxy groups.
Claim 12
Dependent Claim
19 words
A process as claimed in claim 10 wherein the dispersant is an amide or a salt of a polyester.
Claim 13
Dependent Claim
33 words
A process as claimed in claim 9 wherein the dispersing agent mixture comprises a synergist capable of binding at least one of the components in the dispersing agent mixture of the pigment particles.
Claim 14
Dependent Claim
16 words
A process as claimed in claim 12 wherein the synergist is a derivative of the pigment.
Claim 15
Dependent Claim
34 words
A process as claimed in claim 1 wherein the aqueous slurry contains at least one resin in an amount of up to 50% by weight based on dry matter in the organic pigment dispersion.
Claim 16
Dependent Claim
27 words
A process as claimed in claim 9 wherein the dispersing agent mixture is present in an amount of up to 30% by weight based on the pigment.
Claim 17
Dependent Claim
31 words
A process as claimed in claim 1 wherein the organic pigment is selected from the group consisting of azo pigments such as diarylides and lake pigments, phthalocyanines, and other condensation pigments.
Claim 18
Dependent Claim
49 words
A process as claimed in claim 1 wherein the removal of a substantial part of the water is performed by contacting the dispersion with a set of surfaces with different affinity for water and the organic pigment dispersion, respectively, and thereafter isolating water and the organic pigment dispersion separately.
Claim 19
Dependent Claim
59 words
A process as claimed in claim 17 wherein the removal of water from the dispersion is performed by passing the dispersion over a set of rollers, the surface material thereof having different affinity for water and the non-aqueous medium, respectively, and then removing water and the pigment dispersion in the non-aqueous medium, respectively, from the surface of each roller.
Claim 20
Dependent Claim
19 words
A process as claimed in claim 18 wherein the surface materials of the rollers are copper and steel, respectively.
Claim 21
Dependent Claim
21 words
A process as claimed in claim 18 wherein the surface materials of the rollers are exposed and non-exposed off-set plates, respectively.
Claim 22
Dependent Claim
19 words
A process as claimed in claim 1, wherein the organic pigment constitutes 2-5% by weight of the aqueous slurry.
Claim 23
Dependent Claim
19 words
A process as claimed in claim 1, wherein the organic pigment constitutes 2-10% by weight of the aqueous slurry.
Claim 24
Dependent Claim
28 words
A process as claimed in claim 1, in which the aqueous slurry is obtained directly from an aqueous slurry in which the pigment is formed, without initial filtration.
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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) | 1991-08-23 | 1992-02-22 | 1992-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-23 | 1996-02-22 | 1996-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-23 | 2000-02-22 | 2000-08-23 | $7700.00 | Window Closed / Lapsed |