CRYSTAL MODIFICATION OF PIGMENT RED 53:1

• Main Authors: DEUBEL, REINHOLD, WESTER, NORBERT, SCHUI, FRANZ
• Format: Patent
• Language: English; French
• Published: 31.03.1987
• Edition: 4
• Subjects: ADHESIVES; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; CORRECTING FLUIDS; DYES; FILLING PASTES; INKS; LAKES; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; MORDANTS; NATURAL RESINS; ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; POLISHES; USE OF MATERIALS THEREFOR; WOODSTAINS

of the disclosure: 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.-modifiaction.