Patent GB-384313-A (GB)
Title: Improvements in or relating to the colouration of textile materials
IPC: D06P5/15
Filed: 1931-05-22
Abstract: Cellulose esters or ethers, dyeing; printing.--Aldehyde or ketone sulphoxylates of metals exhibiting more than one valency, for use as reducing discharge or resist agents in textile printing, are obtained by the interaction of an aldehyde or ketone sulphoxylate and a metal salt having reducing properties by virtue of the valency of the metal.  Specified metals are tin, titanium, copper and iron and specified aldehydes and ketone are formaldehyde, acetaldehyde, benzaldehyde and acetone.  The resulting sulphoxylates of the reducing metals may be isolated and incorporated in the discharge or resist preparations or the crude mixture of sulphoxylate and reducing metal salt may be used.  The discharge or resist preparations may also contain suitable thickening agents, catalysts such as anthraquinone, or colouring matters resistant to the reducing action, e.g. the insoluble metal compounds of leuco vat dyes described in Specification 378,917. They are specially suitable for the production of pattern effects on materials made of or containing cellulose esters or ethers but are also applicable to materials made of cotton, silk, wool or regenerated cellulose.  For the application to cellulose ester or ether materials swelling or penetrating agents such as alcohols or phenols, e.g. hydroquinone may be incorporated. The following examples are specified.  (1) A cellulose acetate material dyed with 4-nitro-2 - methoxybenzene - azo - dimethylaniline is printed with an aqueous paste containing sodium formaldehyde sulphoxylate, stannous chloride, gum arabic and methylated spirit, dried, aged, washed, soaped and dried to obtain a white discharge on a red ground.  (2) A cellulose acetate material dyed with 5-nitro-2-aminoanisol-->o -oxyethyl-1-naphthylamine is printed with an aqueous paste containing sodium formaldehyde sulphoxylate, titanous chloride, gum arabic, and methylated spirit, dried, aged, washed, soaped and dried to obtain a white discharge on a violet ground.  (3) An aqueous solution containing the calculated quantity of stannous chloride is added to a 10 per cent solution of sodium formaldehyde sulphoxylate, the resulting precipitate pressed out to a 30 per cent concentration is mixed with gum arabic, and the mixture is printed on a cellulose acetate material dyed with Dispersol yellow 3G; the material is then dried, aged, washed, soaped and dried to obtain a white discharge on a yellow ground.ALSO:Aldehyde or ketone sulphoxylates of metals exhibiting more than one valency, for use as reducing discharge or resist agents in textile printing, are obtained by the interaction of an aldehyde or ketone sulphoxylate and a metal salt having reducing properties by virtue of the valency of the metal.  Specified metals are tin, titanium, copper and iron and specified aldehydes and ketones are formaldehyde, acetaldehyde, benzaldehyde and acetone.  In an example an aqueous solution containing the calculated quantity of stannous chloride is added to a 10 per cent solution of sodium formaldehyde sulphoxylate and the resulting precipitate is pressed out to a 30 per cent concentration for incorporation in a discharge printing paste.