Patent GB-391773-A (GB)
Title: Improvements in the fixation of metal compounds on textile materials
IPC: D06M11/46
Filed: 1931-10-15
Abstract: Insoluble metal compounds are fixed on textile materials by treatment with a single bath of an aqueous liquid containing reagents which interact with slow formation of the desired compound.  The process is particularly applicable to the delustring of materials such as natural or artificial silk by the fixation of substantially white insoluble metal oxide compounds thereon, the slow deposition from a single bath permitting any desired degree of delustring to be attained.  Artificial silk, whether of the regenerated cellulose type or made of cellulose acetate, formate, propionate, or butyrate, or other cellulose esters, or of ethyl or benzyl cellulose or other cellulose ethers, may be delustred in this manner.  Mixed materials, for example, materials consisting of natural silk or one of the above types of artificial silk in admixture with cotton, wool, or other natural fibre may also be treated.  The invention is applicable to treatments such as weighting and mordanting.  The process may be carried out by treating the textile material with a bath of an aqueous liquid containing a metal salt such as titanium sulphate or chloride and either a neutral base such as urea or a salt of a strong base with a weak acid, for example, sodium acetate.  The bath is then gradually heated to a suitable temperature, which may be above 55-60 DEG  C. in the case of a titanium salt and urea bath, to cause slow liberation or the metal oxide.  Instead of urea, derivatives such as methyl urea or semicarbazide, aminocarboxylic or aminosulphonic acids, for example, glycerine and other amino fatty acids, or aminohydroxy compounds, for example a -aminopropane-b  : g -diol or other aminodihydroxy or aminopolyhydroxy compounds may be used. Metal oxides more strongly basic than titanium oxide may be deposited from solutions of their salts by salts of strong bases with weak acids such as silicic or boric acid, or organic acids such a acetic acid.  For example, sodium acetate may be used with stannic chloride to deposit stannic oxide, and in the case of aluminium salts sodium silicate may be employed.  Instead of adding the whole of the reagent adapted to react with the metal salt at first, it may be added intermittently or continuously during the delustring operation.  If desired, especially in the cases where the metal salt employed contains free acid, a strong alkali may be used to neutralize the acidity, but not to such an extent as to cause material precipitation.  In the case of a delustring bath prepared from titanium chloride or sulphate, the acidity may be adjusted to about pH5 by the addition of ammonia, the urea or like body being added subsequently.  When metallic salts such as titanic chloride decomposed by warm water are used, the salt may be diluted with an organic solvent such as alcohol before admixture with water. Other additions may be made to the treatment baths, for example, when treating cellulose esters or ethers, a swelling agent such as a thiocyanate, a water-soluble alcohol such as ethyl alcohol, or a ketone such as acetone may be present.  To prevent the separation of the metal oxides at a greater rate than that at which they can be taken up by the material treated, a protective colloid such as a highly sulphonated oil or a sulphuric ester of a higher aliphatic alcohol or a basic compound such as oleyldiethylethylenediamine may be added to the bath.  Materials sold under the Registered Trade Marks "Sapamine" and "Gardinol" are mentioned as suitable. Particularly when employing titanium compounds, the parts of the apparatus coming in contact with the liquid are advantageously made of non-metallic material such as wood, or of enamelled material. Examples describing the delustring, weighting, and mordanting of cellulose acetate yarns and fabrics are given.  Specification 391,772 is referred to.