US4247695A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparation of quinacridone pigments using moderately concentrated acid
Assignee: Novartis Corp
•
Filing: 1979-02-26
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Granted: 1981-01-27
•
Expires: 1999-02-26
Abstract
Abstract A process for preparing beta or gamma crystals of linear quinacridone, substituted quinacridone or solid solutions thereof by contacting premilled quinacridone with 45-60% by weight sulfuric acid and 0-10% by weight of a surfactant based on the quinacridone at a weight ratio of acid to quinacridone of 3:1-6:1 to form a slurry, agitating said slurry for a period of time at 45°-75° C., adding water to form a dilute slurry, agitating said dilute slurry for a period of time at 75°-95° C. and separating quinacridone from the liquid of the dilute slurry.
Inventors
- 👤 Patrick H. Fitzgerald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:18
CPC Classifications
C; C09; C09B; C09B67/00; C09B67/0033; C09B67/0034; C09B67/0036; C09B67/0001; C09B67/0014; C09B67/0017
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
134 words
A process for preparing beta or gamma linear quinacridone pigments, substitutued quinacridone pigments and solid solutions thereof which comprises dry milling linear quinacridone, substituted quinacridone or mixtures thereof until the particle size is less than the desired size, mixing the dry milled product with 0-10% by weight of a surfactant based on the pigment and 45-60% by weight sulfuric acid at a weight ratio of said acid solution to quinacridone of 3:1-6:1 to form a quinacridone slurry at a temperature of 40°-75° C., agitating the slurry for at least 30 minutes, adding at least an equal volume of water to the slurry to form a dilute slurry, agitating the dilute slurry for at least 30 minutes at a temperature of 75°-95° C. and separating the quinacridone pigment and the liquid of the dilute slurry.
Claim 2
Dependent Claim
134 words
A process for preparing beta or gamma linear quinacridone pigments, substitutued quinacridone pigments and solid solutions thereof which comprises dry milling linear quinacridone, substituted quinacridone or mixtures thereof until the particle size is less than the desired size, mixing the dry milled product with 0-10% by weight of a surfactant based on the pigment and 45-60% by weight sulfuric acid at a weight ratio of said acid solution to quinacridone of 3:1-6:1 to form a quinacridone slurry at a temperature of 40°-75° C., agitating the slurry for at least 30 minutes, adding at least an equal volume of water to the slurry to form a dilute slurry, agitating the dilute slurry for at least 30 minutes at a temperature of 75°-95° C. and separating the quinacridone pigment and the liquid of the dilute slurry.
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein the sulfuric acid is 50-55% by weight.
Claim 4
Dependent Claim
14 words
The process of claim 1 wherein linear quinacridone and an substituted quinacridone are milled.
Claim 5
Dependent Claim
12 words
The process of claim 3 wherein the substituted quinacridone is 2,9-dimethyl quinacridone.
Claim 6
Dependent Claim
14 words
The process of claim 4 wherein the linear quinacridone/2,9-dimethyl quinacridone are 20%/80% by weight.
Claim 7
Dependent Claim
18 words
The process of claim 4 wherein the amount of surfactant is 1-10% by weight based on the quinacridone.
Claim 8
Dependent Claim
11 words
The process of claim 6 wherein the surfactant is dimethyldicocoammonium chloride.
Claim 9
Dependent Claim
18 words
The process of claim 1 wherein the amount of surfactant is 1-10% by weight based on the quinacridone.
Claim 10
Dependent Claim
11 words
The process of claim 8 wherein the surfactant is dimethyldicocoammonium chloride.
Claim 11
Dependent Claim
22 words
The process of claim 1 wherein 10-100% by weight of aluminum sulfate based on the quinacridone is dry milled with the quinacridone.
Claim 12
Dependent Claim
22 words
The process of claim 1 wherein 10-20% by weight of aluminum sulfate based on the quinacridone is dry milled with the quinacridone.
Claim 13
Dependent Claim
18 words
The process of claim 10 wherein the amount of surfactant is 1-10% by weight based on the quinacridone.
Claim 14
Dependent Claim
11 words
The process of claim 12 wherein the surfactant is dimethyldicocoammonium chloride.
Claim 15
Dependent Claim
14 words
The process of claim 13 wherein linear quinacridone and an substituted quinacridone are milled.
Claim 16
Dependent Claim
18 words
The process of claim 11 wherein the amount of surfactant is 1-10% by weight based on the quinacridone.
Claim 17
Dependent Claim
11 words
The process of claim 15 wherein the surfactant is dimethyldicocoammonium chloride.
Claim 18
Dependent Claim
14 words
The process of claim 16 wherein linear quinacridone and substituted quinacridone are dry milled.
References Cited (Backward Citations)
US3051720A
Cited
US3017414A
Cited
US3030370A
Cited
US3326918A
Cited
US3362957A
Cited
DE2034499A1
Cited
US3697464A
Cited
US4024148A
Cited
US4015998A
Cited
US4094699A
Cited
US4088506A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-27 | 1984-07-28 | 1985-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-27 | 1988-07-28 | 1989-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-27 | 1992-07-28 | 1993-01-27 | $7700.00 | Window Closed / Lapsed |