Abstract: Nigrosine base (Color Index 50,415:1) which is pyrophoric is made non-pyrophoric by sparging a solution thereof in aniline with air.

Abstract: Adsorbents are provided for the affinity-specific separation of macromolecular materials, particularly biopolymers, the adsorbents comprising a polymeric carrier on to which an affine residue for the macromolecular material is covalently bound, either directly or via polymeric spacer. Preferred affine residue is comprised of a specific complex formers which are base-specific and/or structure specific for the macromolecular material. The invention also provides novel complex formers comprising a certain dyestuff residues and processes for their preparation.

Abstract: The ammonium salt of Nigrosine Sulfonic Acid, a novel compound, has been discovered to produce a black flexographic ink with superior water-resistance properties.

Abstract: Nigrosine base is aryl sulfonated to produce a dye useful in jet-printing inks.

Abstract: Dyestuffs are provided which contain one or more 1,3-dicyanobenzene radicals linked to the dyestuff at the 2-, 4- or 6-position, with halogen substituents in both of the remaining two of these positions and an electron-attracting substituent in the 5-position. These dyestuffs reactively dye cellulose at low temperatures and are less prone to "acid-bleeding" than some known reactive dyes. More particularly, those dyestuffs have the formula: ##STR1## where D is a chromophoric groupn is 1 or 2, ##STR2## where R is H, C.sub.1-4 alkyl, C.sub.1-4 alkyl substituted by OH, OSO.sub.3 H, CN or SO.sub.3 H or is phenyl.Each hal independently represents a chlorine or fluorine atom occupying one of the remaining 2-, 4- and 6-positions of the benzene nucleus, and Y is H, F, Cl, CN, NO.sub.2 or SO.sub.3 H.

Abstract: Novel dyestuffs containing amino or imino groups and their preparation are provided.These dyestuffs have the general formula ##STR1## wherein R is --N(R.sub.3)CH.sub.2 --Z or --N.dbd.CH--Z, X is N or CR.sub.6 where R.sub.6 is a hydrogen atom or an optionally substituted alkyl or aryl group, Y is S.sup..sym., O.sup..sym., N or N.sup..sym. R.sub.7 where R.sub.7 is a hydrogen atom or an optionally substituted alkyl or aryl group, R.sub.1, R.sub.1 and R.sub.2 each represent a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms, or R.sub.1 and R.sub.2 together with the nitrogen atom complete a heterocyclic ring, or one of R.sub.1 and R.sub.2 can be hydrogen and the other of R.sub.1 and R.sub.2 can be aryl, Z is a group which comprises both an activating group which contains at least one double bond system and also a ballasting group and R.sub.4 and R.sub.5 each represent optional substituents or form an annelated benzene ring.

Abstract: Nigrosine and induline dyes having improved rheological properties are prepared by treating a base of the nigrosine or induline series with between 15 and 30% by weight of phthalic anhydride, at a temperature between 135.degree. and 150.degree. C. The resulting dyes are readily dispersible in plastics and inks and provide finished products having improved flowability.

Abstract: A dyestuff of the formula ##STR1## where D is a chromophoric residuen is 1 or 2Z is ##STR2## where R is H, C.sub.1-4 alkyl, C.sub.1-4 alkyl substituted by OH, OSO.sub.3 H, CN or SO.sub.3 H or is phenyleach hal independently represents a chlorine or fluorine atom occupying one of the remaining 2-, 4- and 6-positions of the pyridine nucleusX is F, Cl, CN or NO.sub.2Y is H, F, Cl, CN or NO.sub.2.These dyestuffs reactively dye cellulose at low temperatures and are less prone to "acid bleeding" than some known reactive dyes.

Abstract: The present invention provides 1,3,7-trinitrophenazine-5-oxide which has an excellent sensitization effect on organic photoconductors, as well as a photoconductive sensitive material comprising said compound and an organic photoconductor.