US3900459A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing high molecular weight azo pigment
Assignee: Dainichiseika Color and Chemicals Mfg Co Ltd
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Filing: 1973-03-15
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Granted: 1975-08-19
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Expires: 1993-03-15
Abstract
Abstract A process is described for the preparation of high molecular weight azo pigments characterized by high crystallinity and clear hue by coupling a diazo component with a coupling component wherein the improvement in the process comprises preparing a solution or partial dispersion of said diazo component by diazotizing a primary aromatic amine in a hydrophobic organic solvent, preparing a solution or partial dispersion of said coupling component by mixing said coupling component in a hydrophobic organic solvent and forming a coupling reaction mixture by mixing a solution or partial dispersion of said diazo component with a solution or partial dispersion of said coupling component.
Inventors
- 👤 Kimihide Kawamura
- 👤 Shojiro Horiguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:37
CPC Classifications
C; C09; C09B; C09B41/00; C09B41/001; C09B41/002
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
100 words
IN A PROCESS FOR PREPARING A HIGH MOLECULAR WEIGHT AZO PIGMENT BY COUPLING A DIAZO COMPONENT WITH A COUPLING COMPONENT, THE IMPROVEMENT WHICH COMPRISES: PREPARING A SOLUTION OR A PARTIAL DISPERSION OF A DIAZO COMPONENT BY DIAZOTIZING A PRIMARY AROMATIC AMINE IN A HYDROPHOBIC AROMATIC SOLVENT HAVING A BOILING POINT GREATER THAN 150*C, PREPARING A SOLUTION OR A PARTIAL DISPERSION OF A COUPLING COMPONENT HAVING TWO COUPLING POSITIONS IN SAID HYDROPHOBIC AROMATIC SOLVENT AND FORMING A COUPLING REACTION MIXTURE BY MIXING THE SOLUTION OR PARTIAL DISPERSION OF THE DIAZO COMPONENT WITH THE SOLUTION OR PARTIAL DISPRSION OF THE COUPLING COMPONENT.
Claim 2
Dependent Claim
100 words
IN A PROCESS FOR PREPARING A HIGH MOLECULAR WEIGHT AZO PIGMENT BY COUPLING A DIAZO COMPONENT WITH A COUPLING COMPONENT, THE IMPROVEMENT WHICH COMPRISES: PREPARING A SOLUTION OR A PARTIAL DISPERSION OF A DIAZO COMPONENT BY DIAZOTIZING A PRIMARY AROMATIC AMINE IN A HYDROPHOBIC AROMATIC SOLVENT HAVING A BOILING POINT GREATER THAN 150*C, PREPARING A SOLUTION OR A PARTIAL DISPERSION OF A COUPLING COMPONENT HAVING TWO COUPLING POSITIONS IN SAID HYDROPHOBIC AROMATIC SOLVENT AND FORMING A COUPLING REACTION MIXTURE BY MIXING THE SOLUTION OR PARTIAL DISPERSION OF THE DIAZO COMPONENT WITH THE SOLUTION OR PARTIAL DISPRSION OF THE COUPLING COMPONENT.
Claim 3
Dependent Claim
34 words
The process according to claim 1, wherein said coupling reaction mixture in the hydrophobic aromatic solvent is heated at 100*-250*C for 0.5-30 hours with stirring, whereby pure crystals of said azo pigment are obtained.
Claim 4
Dependent Claim
21 words
The process according to claim 1, wherein said hydrophobic organic solvent is mono-, di-, tri- or tetra-chlorobenzene, nitrobenzene, nitrotoluene or nitrochlorobenzene.
Claim 5
Dependent Claim
33 words
The process according to claim 1, wherein a mineral acid is added to the solution or partial dispersion of said coupling component and to the solution or partial dispersion of said diazo compound.
Claim 6
Dependent Claim
13 words
The process according to claim 4, wherein said mineral acid is hydrogen chloride.
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) | 1978-08-18 | 1979-02-17 | 1979-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-18 | 1983-02-17 | 1983-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-18 | 1987-02-17 | 1987-08-19 | $7700.00 | Window Closed / Lapsed |