Patent GB-374884-A (GB)
Title: Improvements in or relating to the dyeing of materials made of or containing cellulose esters or ethers
IPC: D06P1/22
Filed: 1931-01-05
Abstract: Cellulose esters or ethers, dyeing; vat dyes, dyeing with; printing; indigoid and thioindigoid dyes.--Cellulose esters or ethers, whether alone or in admixture with other fibres, are dyed, printed, stencilled or otherwise coloured by applying thereto a dyestuff of the type in which an indole or thionaphthene residue is united at the 2 or 3 position with a benzene or naphthalene nucleus of which the carbon atoms do not form part of another benzene ring.  In general such dyestuffs, when of o-quinonoid structure, are obtainable by (a) condensing isatins or thioisatins or nuclear substitution products thereof, or derivatives of these in which the a -ketonic oxygen has been replaced by a reactive group or atoms, e.g. an arylimide group or chlorine or bromine atoms, with phenols or naphthols or derivatives thereof, such as the 4-methoxy-, 4-chloro-, 4-bromo- or 4-ethylthio, derivatives of 1 naphthol, or 4-oxyacenaphthene or (b) condensing indoxyls or thioindoxyls or a -carboxylic acids thereof with suitable compounds containing the -CO-CO-grouping such as b -naphthoquinone.  Specified isatin and thioisatin derivatives are 5 : 7-dichlorisatin, 5 : 7-dibromisatin, 5 : 7-dibromthioisatin, 5-ethoxythioisatin, 1 : 2-, 2 : 1- or 2 : 3-naphthisatins, 8-chlor-1 : 2-naphthisatin, 1 : 2-, 2 : 1-or 2 : p  3-naphthioisatins and their chlorinated or brominated derivatives, isatin - a  - chloride and thioisatin-a -p - dimethylaminophenylimide.  Specified indoxyl and thioindoxyl derivatives are 5 : 7 - dibromindoxyl, 5 : 7 - dibromthio - indoxyl, 2 : 3- or 2 : 1-naphthioindoxyl, anthracene-2 : 3-indoxyl or -thioindoxyl and anthraquinone-2 : 3-indoxyl. Dyestuffs of p-quinonoid structure, such as those obtainable by condensing isatins or thioisatins with carbazole or thiodiphenylamine, may also be employed.  The dyestuffs may be applied by any convenient method, e.g. (1) from alkaline vats containing hydrosulphite and either caustic alkali or ammonia or amines such as monomethyl-, monoethyl- or monopropylamine, mono-, di or tri-ethanolamines, pyridine or piperidine, (2) from alkaline vats prepared as described in Specification 262,506, [Class 15 (ii), Dyeing, Processes &c. for], (3) as suspensions or dispersions of the unreduced dyestuffs, such as the dispersions obtainable as described in Specifications 219,349, 224,925, 242,393, 242,711, 269,960, 273,819, 273,820, 322,737 and 323,788, [all in Class 2 (iii), Dyes &c.],  The dyestuffs may also be incorporated in discharge preparations.  The following examples are given: (1) Cellulose acetate knitted goods are dyed blue by treatment for 1-2 hours at 80 DEG  C. in an aqueous bath containing 2-indole-2<1>-naphthalene indigo (obtainable from isatin-a -anilide and a -naphthol) dispersed with turkey red oil and soap.  (2) Hanks of cellulose acetate yarn are dyed blueish red by treatment for 2 hours at 75 DEG  C. in an aqueous bath containing 2 - thionaphthene - 1<1> - naphthalene indigo (obtainable from thioisatin-a -dibromide and b -naphthol) similarly dispersed.  (3) Hanks of cellulose acetate yarn are dyed blue by vatting for 1-1 \ba1/2\be hours at 60 DEG  C in an aqueous liquor containing 2-indole-2<1>-naphthalene indigo, turkey red oil, caustic soda and sodium hydrosulphite and thereafter oxidizing in the air and treating in a bath containing sodium perborate and soap.  (4) A cellulose acetate woven fabric is printed blue with an aqueous paste containing 2-indole-2<1>-naphthalene indigo, gum arabic and methylated spirit, dried, steamed for 1 hour, washed, soaped, washed and dried.  The use of the following additional dyestuffs is specified, viz. 2-indole-2<1>-(5-phenylamino) benzene indigo (obtainable from isatin-a -chloride and m-oxydiphenylamine), 2-thionaphthene-2<1>-naphthalene indigo (obtainable from thioindoxylcarboxylic acid and b -naphthoquinone), 2-(5 : 7-dibromindole)-2<1>-(4<1>-brom.) naphthalene indigo (obtainable by brominating the dyestuff from 5 : 7-dibromisatin-a -chloride and a -naphthol), and the dyestuff from 5 : 7-dibromisatin-a -chloride and 4-oxyacenaphthene.  The use of the process of Specification 341,408 is disclaimed. Specifications 197,281, 263,473, 284,376 and 285,104, [all in Class 15 (ii) Dyeing, Processes &c. for], also are referred to. The Provisional Specification describes the use of dyestuffs in general in which an indole or thionaphthene residue is united to a nucleus which is not of the indole or thionaphthene series and specifies the dyes obtainable by condensing isatins or thioisatins with a -anthrol, a -oxyanthrahydroquinone, 1-phenyl - 3 - methyl - 5 - pyrazolone and acenaphthenone, or by condensing indoxyls or thioindoxyls with acenaphthenequinone or 4-halogenacenaphthenequinones. 4-Ethylthio-1-naphthol is obtainable by treating 4-thiol-1-ethylcarbonatonaphthol in alcoholic solution with ethyl sulphate in presence of caustic soda and saponifying the resulting 4-ethylthio-1-ethylcarbonatonaphthol with alcoholic soda.