The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 07, 1992
Filed:
Feb. 21, 1990
Heinrich Frolich, Niedernhausen, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
The invention relates to a novel crystallographic modification (.beta.-modification) of the pigment of the formula I ##STR1## The .beta.-modification shows reflections in the Cu-K.sub..alpha. radiation X-ray diffraction spectrum at the following diffraction angles 2.theta. (accuracy .+-.0.2.degree.): at 21.95.degree. a maximum of high intensity, at 5.40.degree., 7.30.degree., 10.85.degree., 14.50.degree. and 27.60.degree. maxima of medium intensity and at 10.05.degree., 12.80.degree., 16.40.degree., 17.95.degree., 24.65.degree. and 25.80.degree. maxima of low intensity. The .beta.-modification is obtainable by coupling diazotized N-(3-amino-4-methylbenzoyl)-sulfanilic acid in an aqueous medium in the presence or absence of an organic solvent onto alkali-dissolved 2-hydroxy-4'-methoxy-3-naphthanilide and laking the coupling product by adding a calcium salt, at least one cation-active surfactant having been added at the latest prior to laking, and heating an aqueous suspension of the laked azo dye at a temperature of 130.degree. to 180.degree. C. The .beta.-modification is suitable for pigmenting printing inks, surface coatings, plastic compositions, filaments and paper, in particular for pigmenting polystyrene, copolymers based on polystyrene, polyolefins, copolymers of polyolefins and polyvinyl chloride.