Cationic fixing agents

A single-bath method can be used if desired. The dyes are dissolved separately and added to the dyebath which already contains an ethylene oxide condensate which acts as an anti-precipitant. The dyebath is adjusted to pH 5 to 5-5 with acetic acid and sodium acetate and the goods are entered at 40 to 45°C (104 to 113°F). A period of 45 minutes is taken to raise the temperature to the boil, at which it is maintained for one hour. Alternatively, the acrylic fibre may be dyed first and then the same liquor is neutralized and the cellulosic fibre is dyed. Application of a cationic fixing agent improves wet fastness of direct dyes but copper after-treatment should be avoided because this can have an adverse effect on the light fastness of the cationic dye. Very good fastness is obtained if, after the acrylic component has been dyed, the cellulosic fibre is brought to shade with vat dyes. 

The value of A ex is, of course, fixed for any given cation-extracting agent-solvent system. Analytically important distribution coefficients, D, can be varied by changing the concentration of ligand relative to that of the metal and more significantly by adjusting the pH for 50% extraction D = 1 and equation (21) reduces to... 

Because many direct dyes do not have good washfastness and lightfastness, their dyeings on cotton are often treated with a chemical agent, in what is commonly known as an aftertreatment process. The most widely used aftertreatment methods involve (1) cationic fixatives, (2) copper sulfate, or (3) diazotiza-tion and coupling reactions. The first and third methods are designed to enhance wash-... 

Cationic derivative of organic base. Substantive fixing agent to prevent bleeding of direct colors. Improves fastness to wet environment. Used alone, in dyebath rinse, or with resins. 

Sanfix. [Sanyo Chem. industries] Cationic resins fixing agent for dirut and reactive dyes. 

Cationic surfactants are used as corrosion inhibitors, flotation aids, biocides, fungicides, and disinfectants. Their use is, however, limited, due to a relatively high cost. Pyridinium salts are employed in the textile industry as dye fixing agents during fabric dyeing, as well as in final fabric finishing. For example, Xelan... 

Pro-Tein. [Maybro ] Hydrolyzed collagen derivs. cationic substantivity agent, anti-irritant fix hair prods., facial toners, ant ierspinmts, after shaves. 

Quat-Pro. [Maybrodc] Hydrcdyzed protein derivs. cationic substantivity agent moisturizer, film-framer fix hair and sldn care prods. 

Water-insoluble pigments have a somewhat limited, but nonetheless essential, part to play in the colouration of certain papers. They are normally applied as anionic dispersions. They have virtnaUy no affinity for ceUulosic fibres and instead rely upon either mechanical retention from the paper machine itself or flocculation via a cationic product (fixing agent) to produce small floes which can be retained on the fibre snrface. 

Fixing agents are cationic products which are added to give complete fixation of the colourant when ambient conditions prevent this occurring naturally. 

The existence of primary stickles (from raw materials) and secondary stickles, which were built by the interaction in such systems, has been described, together with many different characterization methods(including mechanical methods) for quantifying the efficiency of different fixing agents [55, 56]. In addition, physicochemical methods such as measuring the cationic demand, the zeta-potential, or the turbidity of wastewater have been applied. 

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