Patent US4298398A successfully refreshed from Google Patents.
US4298398A
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US
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Process for converting premilled crude quinacridone to pigmentary form
Assignee: Novartis Corp
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Filing: 1980-08-28
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Granted: 1981-11-03
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Expires: 2000-08-28
Abstract
Abstract Process for converting premilled quinacridone to pigmentary form by contacting the premilled quinacridone with aqueous alkaline medium in the presence of a quaternary ammonium compound.
Inventors
- 👤 Patrick H. Fitzgerald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:19
CPC Classifications
C; C09; C09B; C09B67/00; C09B67/0001; C09B67/002; C09B67/0014
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
144 words
A process for converting premilled crude quinacridone to pigmentary form by contacting the premilled quinacridone with an aqueous alkaline medium having a pH of at least 10 in an amount sufficient to intimately contact the premilled crude quinacridone at a temperature of at least 85° C. in the presence of at least one quaternary ammonium compound of the formula (n-C 4 H 9 ) 3 R-N + X - where R- is --CH 3 n-C 4 H 9 , --CH 2 C 6 H 5 , --C 2 H 5 , or n-C 3 H 7 and X - is Cl - , Br - , I - , ##STR2## OH - , or NO 3 - , wherein the quaternary ammonium compound is present in an amount of from 2 to 15% by weight, based on the weight of the premilled crude quinacridone.
Claim 2
Dependent Claim
144 words
A process for converting premilled crude quinacridone to pigmentary form by contacting the premilled quinacridone with an aqueous alkaline medium having a pH of at least 10 in an amount sufficient to intimately contact the premilled crude quinacridone at a temperature of at least 85° C. in the presence of at least one quaternary ammonium compound of the formula (n-C 4 H 9 ) 3 R-N + X - where R- is --CH 3 n-C 4 H 9 , --CH 2 C 6 H 5 , --C 2 H 5 , or n-C 3 H 7 and X - is Cl - , Br - , I - , ##STR2## OH - , or NO 3 - , wherein the quaternary ammonium compound is present in an amount of from 2 to 15% by weight, based on the weight of the premilled crude quinacridone.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein X - is Cl - or Br - .
Claim 4
Dependent Claim
24 words
The process of claim 2 wherein the aqueous alkaline medium is present in at least 4 times the weight of the premilled crude quinacridone.
Claim 5
Dependent Claim
19 words
The process of claim 3 wherein the premilled quinacridone is contacted with the aqueous alkaline medium at ambient pressure.
Claim 6
Dependent Claim
18 words
The process of claim 4 wherein the pH of the aqueous alkaline medium is from 12 to 13.5.
Claim 7
Dependent Claim
31 words
The process of claim 5 wherein the quaternary ammonium compound is present in an amount of from 5 to 10% by weight, based on the weight of the premilled crude quinacridone.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |