Preparation of linea, unsubstituted quinacridone pigments of...

Details Preparation of linea, unsubstituted quinacridone pigments of... Preparation of linea, unsubstituted quinacridone pigments of...

C - Chemistry, Metallurgy

09

B

C09B 48/00 (2006.01) C08K 5/00 (2006.01) C08K 5/3437 (2006.01) C09B 67/10 (2006.01) C09B 67/52 (2006.01)

Patent

CA 2136598

Preparation of linear, unsubstituted quinacridone pig- ments of the .beta.-phase linear, unsubstituted quinacridone pigments of the .beta.-phase can be produced in an environmentally friendly manner by a) cyclizing 2,5-dianilinoterephthalic acid in poly- phosphoric acid or a polyphosphoric ester to the quinacridone, b) then hydrolyzing the quinacridone with water at a temperature of at least 40°C, preferably at from 60 to 100°C, to obtain a finely divided quinacridone pigment crude which is predominantly in the .alpha.-phase, c) then optionally wet grinding the finely divided quinacridone pigment crude from b) (pre-pigment), and d) then heating the crude pigment from b) or the pre- pigment from c) to a temperature between 120 and 200°C in the presence of from 0.1 to 1.5 times the amount of an inorganic base, based on the weight of the crude pigment, in an inert liquid medium (solvent finish). To improve the depth and hue of the color, an oxidative treatment with a peroxodisulfate can be carried out subsequently.

Affiliated with

Also associated with

Rating

Preparation of linea, unsubstituted quinacridone pigments of... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Preparation of linea, unsubstituted quinacridone pigments of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Preparation of linea, unsubstituted quinacridone pigments of... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1725439