Clayton Aniline Co., Ltd.

Ciba-geigy Corporation

John D Hildreth

David G Evans

Anton F Tschopp

David G Haslam

David E Allen

2-Naphthylamine-4,8-disulphonic acid is produced by catalytically hydrogenating the ammonium salt of 2-nitronaphthalene-4,8-disulphonic acid using Pt/C or Pd/C as the catalyst.

Catalytic reduction of 2-nitronaphthalene-4,8-disulfonic acid ammonium

The invention provides dyestuffs of the general formula ##STR1## in which R is hydrogen or an alkyl group having 1 to 6 carbon atoms and R' is an alkyl group having 1 to 6 carbon atoms.

Composition of 4-amino-4'-nitrostilbene-2,2'-disulphonic acid diazo

A process for the manufacture of 2,4- and 2,6-diaminotoluenes comprises catalytically hydrogenating the corresponding molten nitro compound in the presence of water, adding hydrochloric acid to form the monohydrochlorides, crystallizing 2,6-diaminotoluene monohydrochloride, filtering it off and, if desired, liberating the free bases by addition of an alkali.

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Macclesfield, United Kingdom

John D Hildreth