Patent GB-718119-A (GB)
Title: Improvements in or relating to a process for improving the whiteness or colour of materials
Inventor: KENDALL JOHN DAVID
IPC: D06L4/657
Filed: 1951-12-07
Abstract: A dressing for a cotton fabric comprises polyvinyl acetate and an oxacyanine compound, e.g.: 3:31:5:51:7:71-hexamethyl - oxacyanine-p-toluene sulphonate.  The oxacyanine compounds which have the general formula:  <FORM:0718119/IV (a)/1> where R1 and R2 are alkyl groups, and X is the anion of a strong organic or inorganic acid and in which both benzene rings may be substituted with non-chromophoric groups are described in the parent Specification. Specification 546,027 also is referred to.ALSO:A compound having the general formula:-  <FORM:0718119/IV(c)/1> where R1 and R2 are alkyl groups and X is the residue of a strong organic or inorganic acid, and in which both benzene rings can be additionally substituted with non-chromophoric groups may be included in a textile "finishing composition" or may be applied to a textile material to which a "finishing" composition has been previously applied.  In examples: (1) oxacyanine compounds are mixed into aqueous starch suspensions which are evaporated to dryness and the products pulverized and are used in example (2) in aqueous pastes for padding cotton fabric.  (3) A starched cotton fabric is passed through an aqueous solution of an oxacyanine compound, dried and ironed.  (4) A white viscose crepe is padded with a composition comprising a urea-formaldehyde precondensate, a softener, ammonia, ammonium chloride and 3 : 31 : 5 : 51 tetramethyl-oxacyanine-p-toluenesulphonate.  (5) A cotton fabric is padded with a solution comprising polyvinylacetate and 3 : 31 : 5 : 51 : 7 : 71 - hexamethyl-oxacyanine p-toluene sulphonate.  (6) A spun rayon poplin is impregnated with a solution comprising a quaternary hydrophobic material obtained by reacting pyridine with the condensation product from stearic acid amide, formaldehyde and hydrochloric acid, sodium acetate and 3 : 31 : 5 : 51 tetramethyloxacyanine-p-toluene sulphonate.  The oxacyanine compounds are described in the parent Specification, and numerous examples of them are given in which the anion X is a sulphate, p-toluene sulphonate, benzene sulphonate, methyl-sulphonate, chloride, bromide or iodide ion, and the benzene rings may be substituted with halogen, alkyl, alkoxy, alkylsulphonyl or sulphonamide groups.  Specification 546,027 also is referred to.ALSO:A compound having the general formula <FORM:0718119/V/1> where R1 and R2 are alkyl groups and X is the residue of a strong organic or inorganic acid and in which both benzene rings may be substituted with non-chromophoric groups, is added to a starch composition for finishing textile materials.  The compound may be added to an aqueous starch suspension which is then evaporated to dryness and the product pulverized and subsequently used in aqueous suspension for finishing textile materials.  The oxacyanine compounds, of which numerous examples are given, are described in the parent Specification.  The anion X may be a sulphate, p-toluene sulphonate, benzene sulphonate, methyl-sulphonate, chloride, bromide or iodide radicle and the benzene rings may be substituted with halogen, alkyl, alkoxy, alkylsulphonyl or sulphonic acid amide groups.  Specification 546,027, [Group IV], also is referred to.