Patent GB-488783-A (GB)
Title: Process for modifying the properties of natural or artificial amphoteric colloids
IPC: D06P1/642
Filed: 1936-11-13
Abstract: The chemical affinities, especially toward dyestuffs, of shaped materials containing natural or artificial amphoteric colloids are modified by causing such materials to react, e.g. before, during or after the dyeing operation, with a compound having at least two functional groups capable of reacting with the basic or acidic groups of the colloid with formation of co-valent linkages, at least one of such groups having an acylating action.  A specified natural amphoteric colloid is wool and specified artificial amphoteric colloids are those described in Specification 459,711. Specified acylating groups are acid anhydride, acid chloride, isocyanate and isothiocyanate groups and specified non-acylating groups are halogen atoms, sulphonic acid ester residues, isourea- or isothiourea-ether, imidoether, imidothioether, aldehyde and cyanamide groups, quinone residues, alkylene oxide groups and residues containing the methylol derivatives of amino or acylamino groups.  Specified compounds used are o -chloro-p-tolyl isocyanate or isothiocyanate, ethylene di - isocyanate, dichloracetic acid anhydride, b -chlorethyl isocyanate and toluenesulpho-b -hydroxyethyl isocyanate.  They may be used alone or in combination with alkylating agents such as alkyl halides, toluenesulphonic acid esters or alkylene oxides, sulphides or imines. In examples: (1) wool is treated for 12 hours under reduced pressure with a moist atmosphere at 60 DEG  C. containing o -chloro-p-tolyl isothiocyanate or with a dry atmosphere containing the corresponding isocyanate; (2) wool is treated with toluenesulpho-b -hydroxyethyl isocyanate at 90 DEG  C. in absence of moisture.  Samples have been furnished under Sect. 2 (5) of (1) an artificial silk prepared as described in example 12 of Specification 459,711, dyed with Alizarin cyanine green G extra and treated for 10 hours with a trichlorethylene solution at 60 DEG  C. of the carbamic acid chloride from b  : b 1-dichlorodiethylamine hydrochloride and phosgene; (2) the product of (1) washed for 15 minutes in an aqueous solution at 40 DEG  C. of sodium carbonate and soap.  o -Chloro-p-tolyl isocyanate and isothiocyanate are obtained by reaction of phosgene and thiophosgene respectively with the hydrochloride of p-aminobenzyl chloride.  b -Chlorethyl isocyanate is obtained by reaction of phosgene with b -chlorethylamine hydrochloride.  Toluenesulpho-b -oxyethyl isocyanate is obtained by reaction of phosgene with the hydrochloride of the p-toluenesulphonic acid ester of b -hydroxyethylamine.  The Specification as open to inspection under Sect. 91 comprises also references to a -chloromethyl ether residues as functional groups and to b -chlorethylisothiourea ether, butadiene dioxide, monomethyolchloracetamide, monomethylolchlorethylmethylamine and the addition product from epichlorhydrin and cyanamide as suitable treatment agents and includes a further example in which a mixed fabric of wool and acetate artificial silk is impregnated with a solution of the addition product from epichlorhydrin and cyanamide, or a salt of such product, squeezed and stored for 16 hours in rolled-up condition in a moist atmosphere at 50 DEG  C.; the product may be deeply dyed with acid dyestuffs at relatively low temperatures.  This subject-matter does not appear in the Specification as accepted.