Process for preparing linear unsubstituted beta-phase...

Details Process for preparing linear unsubstituted beta-phase... Process for preparing linear unsubstituted beta-phase...

C - Chemistry, Metallurgy

09

B

C09B 48/00 (2006.01) C09B 67/52 (2006.01)

Patent

CA 2201438

Process for preparing linear unsubstituted .beta.-phase quinacridone pigments A process for preparing linear unsubstituted .beta.-phase quinacridone pigments or pigment preparations, which comprises a) cyclizing 2,5-dianilinoterephthalic acid in polyphosphoric acid or polyphosphoric ester with a phosphorus pentoxide content of at least 84% by weight to form the quinacridone, b) subsequently hydrolyzing this quinacridone with water or with an aqueous mineral acid solution, preferably orthophosphoric acid solution, at a temperature of at least 40°C, preferably from 60 to 105°C, to form the crude quinacridone pigment which is predominantly in the .alpha.-phase, c) then heating the crude .alpha.-phase quinacridone pigment to a temperature between 120 and 200°C in the presence of a from 0.1 to 3% strength by weight, preferably from 0.2 to 2% strength by weight, inorganic base in water and alkali-stable organic solvents, for the change of phase into coarsely crystalline crude .beta.-phase pigment, and d) subjecting the coarsely crystalline crude .beta.-phase quinacridone pigment, for the fine division to form a pigment or prepigment, to dry or wet milling; and then isolating the resulting finely divided .beta.-phase pigment; e) or subjecting the finely divided .beta.-phase prepigment obtained in d) to a finish treatment in the presence of solvents, and then isolating the pigment.

Méthode pour obtenir des pigments ou des préparations de pigments à base de quinacridone linéaire en phase bêta, sans substitution, consistant à : cycliser l'acide 2,5-dianilinotéréphtalique dans l'acide polyphosphorique ou l'ester polyphosphorique avec une teneur en pentoxyde de phosphore d'au moins 84 % en poids pour former la quinacridone; b) hydrolyser cette quinacridone avec l'eau ou avec une solution aqueuse d'acide minéral, de preférence une solution d'acide orthophosphorique, à une température d'au moins 40 °C, de préférence entre 60 et 105 °C, pour former le pigment brut de quinacridone principalement en phase alpha; c) chauffer ensuite ce pigment à une température de 120 à 200 °C en présence de 0,1 à 3 % en poids, de préférence de 0,2 à 2 %, d'une base minérale dans l'eau et dans des solvants organiques, stables en milieu alcalin, pour le changement de phase en pigment brut phase bêta, grossièrement cristallisé; d) soumettre ce dernier pigment, pour la division fine et la formation de pigment ou de prépigment, au séchage ou au broyage humide; isoler ensuite le pigment en phase bêta finement divisé, ainsi obtenu; e) ou à soumettre le prépigment en phase bêta finement divisé, obtenu en d), à un traitement de finition en présence de solvants, puis à isoler le pigment.

Affiliated with

Also associated with

Rating

Process for preparing linear unsubstituted beta-phase... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for preparing linear unsubstituted beta-phase..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for preparing linear unsubstituted beta-phase... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1896549