公开(公告)号：BR8303382A

公开(公告)日：1984-02-07

申请号：BR8303382

申请日：1983-06-24

Applicant: HOECHST AG

Inventor： SCHUI FRANZ ,  DEUBEL REINHOLD ,  WESTER NOBERT

IPC: C09B29/15 ,  C09B63/00 ,  C09B67/00 ,  C09B67/20 ,  C09B67/26 ,  C09B67/48 ,  C09D7/12 ,  C09D11/02

Abstract: A novel crystallographic modification ( beta -modification) of the pigment C. I. Pigment Red 53:1 is described and claimed which has characteristic reflection values in its X-ray diffraction pattern obtained by means of Cu-K alpha radiation. This novel pigment form is obtained by reacting an aqueous solution of an alkali metal or ammonium salt of the formula 1 (1) with the equivalent amount of a water-soluble barium salt in the presence of a compound of the formula 2 (2) The modification is distinguished by a more yellowish-red shade as compared to the known alpha -modification.