Sun Chemical Corporation

Edward H Sung

George H Robertson

Humberto A Velasquez

Veronica L Chambers

Daphne J Rice

Brian L Thompson

Terrence R Chamberlain

Wengan Wu

John Britanak

Kathleen Marie Kozak

Tracie Tibbs

George H Roberston

Chris M Arizo

James Z Dong

George N Robertson

2,5-di(p-methoxyanilino)terephthalic acid crystal types I and II are made by controlling the pH during the recovery of the oxidized product of the condensation of dimethylsuccinyl succinate with p-methoxyaniline. The resulting 2,5-di(p-methoxyanilino)-terephthalic acid can be converted into 2,9-dimethoxyquinacridone or a solid solution thereof having controlled characteristics.

2,5-di(methoxyanilino) terephthalic acid polymorphs and quinacridones realized therefrom

This invention relates to a method for production of nanoscale size quinacridones through a wet-salt attrition process by combining a crude quinacridone pigment in the presence of (i) an inorganic salt, (ii) an organic liquid in which the quinacridone pigment and salt are substantially insoluble, and (iii) a quinacridone derivative in an amount less than 10 wt. % relative to the quinacridone pigment; discharging the ground quinacridone pigment into water; adding an acid to produce a solution pH of 1.5 or lower; and isolating the quinacridone pigment.

Process for preparing nanoscale quinacridone

A process for the manufacture of a transparent Pigment Yellow 155 or transparent Pigment Yellow 180 is disclosed, said process includes grinding particles of said pigment in the presence of a grinding agent until said particles achieve a surface area of at least about 40 m/g.

Preparation of yellow pigments

A process for conditioning azo pigment with surfactants of ethoxylate alkyl phenols in the presence of a strong alkali in the aqueous condition.

Process for conditioning azo pigments

A process for by oxidizing a quinacridone in a liquid medium with a non-metal oxidant producing a quinacridonequinone.

Preparation of quinacridonequinones and substituted derivatives of same

A method of conditioning an organic crude pigment by treating, under high shear, 1 part by weight of the crude pigment and about 0.5 to 1.9 parts by weight of polyphosphoric acid or polyphosphoric acid methyl ester at a temperature ranging from about 90 to 160&deg; C.

Polyphosphoric acid swelling of organic pigments

A process for producing beta-phase quinacridone by (a) reacting 2,5-dianilino-terephthalic acid with polyphosphoric acid in the presence of 2,5-dianisidino-terephthalic acid at a reaction temperature of at least 85&deg; C.; (b) diluting the reaction mixture with water; (c) drowning the diluted mixture in a water-miscible alkanol; (d) heating the slurry at a temperature of from 100 to 130&deg; C. at a pressure of 20 to 50 psi; and (e) recovering the beta-phase quinacridone.

Process for the preparation of beta-phase quinacridone

A method of acid swelling crude perylene pigment by treating the crude with about 2 to 10 parts by weight of toluene sulfonic acid at an elevated pressure and at temperatures ranging from 40 to 140&deg; C.

Toluene sulfonic acid swelling of perylene pigments

An improved process for producing a substantially pure gamma phase a quinacridone pigment or pigment derivative involving preparing an aqueous slurry of a crude quinacridone in the presence of caustic alkali and a non-polar, water immiscible solvent; and heating said slurry at a temperature above about 120&deg; C.

Growing community of inventors

Cincinnati, OH, United States of America

Edward H Sung