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The article presents research which explored the effects of ultrasound on enzymatic treatment of cotton fabric. The researchers defined the treatment of cotton fibers as an environmentally and non toxic benign process that gained wide recognition for different textile processing applications like bleach cleanup, bio polishing, desizing and bio stoning. They mentioned that enzymes serve as catalysts to enhance complex chemical reactions like hydrolases of cellulose by cellulase as well as starches by amylase.

Commercial dye fixatives with chlorohydrin functionality and polyammonium quaternary centers for ionic dye attraction were investigated as pretreatments for dyeing wool/cotton to union shades. These fixatives form reactive epoxides in extremely basic medium. The basic medium is the pretreatment wet-bath where anionic cellulose reacts with the epoxide. This reaction conveys cationic character to cellulose. To preserve the integrity of wool, pretreatment was restricted to pH] 1, 3 hours at 20C. These conditions allowed union dyeing of wool/cotton blends. Wool, bearing amino groups, was also affected. The prototype chlorohydrin fiber reactive quaternary (FRQuat), QUAT 188, was also investigated because of its small molecular size. Under reaction conditions with QUAT 188, wool dyed and cotton only stained. When wool/cotton union cloth was pretreated with the polymeric counterparts of QUAT 188 such as FREETEX 670 FIXATIVE, LEVOGEN FSE, SANDENE 8425, SANDOSPACE HPB LIQUID, SOLFIX E, and R10110-87 Experimental Fixative, union shades at 1%, 2%, and 3% were obtained. The FRQuat systems were compared to resin/choline chloride (CC) pad/dry/cure systems DMDHEU/CC, glycolated DMDHEU/CC, and methylated DMDHEU/CC for union shade, color strength, and fastness. The FRQuat polymers gave true union shades but the shades were duller and the K/S values were lower than the K/S values for fabrics pretreated with the resins/CC. The wash fastness of the FRQuat fabrics after dyeing with C.I. Acid Red 114, was poorer than that of the resin/amine pretreated fabrics, possibly indicating the presence of adsorbed fixative/dye complex in addition to covalently bonded complex. Therefore, these FRQuat preteatments cannot yet be recommended for union dyeing. [ABSTRACT FROM AUTHOR]

Cellulose crosslinked with polycarboxylic acids, such as 1, 2, 3, 4-butanetetracarboxylic acid (BTCA), previously has been shown to have affinity for cationic (basic) dyes. Because of such chemical modification, the crosslinked cellulose has little affinity for the dyes normally used to color cotton. Similarly, acid dyes, and reactive dyes used only under acidic pH conditions, have no affinity for polycarboxylic acid crosslinked cotton. In the present study, dyeing properties of cotton finished with citric acid crosslinking agent and reactive nitrogenous additives were investigated. It was found that cottons finished with citric acid and certain nitrogenous agents have affinity for several classes of anionic dyes. The treated cottons are receptive to acid, direct, and reactive dyes under prescribed dyeing conditions. Nitrogenous agents used in the study were alkanolamines in the salt form and hydroxyalkyl quaternary ammonium salts. The most effective alkanolamine salt for improvement of the dyeing properties of the crosslinked cotton was triethanolamine hydrochloride (TEAHC1), and the most effective quaternary ammonium salt was tetrakis(2-hydroxyethyl)ammonium chloride. Methods for producing dyeable, smooth drying cottons with modified citric acid cross-linking systems and the dyeing properties of these fabrics are presented. [ABSTRACT FROM AUTHOR]

Previously, we have demonstrated that dyeable easy-care fabric is produced by chemically treating cotton with an N-methylolamlde crosslinking agent and a alkanolamine or hydroxyalkyl quaternary ammonium salt. Conventional pad-dry-cure finishing methods, crosslinking agents, and metal salt catalysts are employed. In more recent studies, we have discovered that inclusion of a reactive glycol or polyethylene glycol in the finishing bath greatly improves the dyeabllity of the treated fabric. The glycol is bound to the substrate through reaction with the croaslinking agent. The treated cotton shows improved color strength upon dyeing with larger molecular weight anionic dyes. Cotton finished with glycol additive, but without nitrogenous additive, does not show the same degree of dye receptivity as does fabric finished with the combination treatment. We investigated various reactive glycol compounds including a series of polyethylene glycols. [ABSTRACT FROM AUTHOR]

Finishing cotton fabrics with polycarboxylic acid orosslinking agents in combination with nitrogenous additives was investigated as a means of introducing dyeability into the smooth drying textiles. Substantial improvement in the dyeing properties of the modified ester-crosslinked cotton was obtained by using various hydroxyalkyl nitrogenous compounds as additives. The most effective was triethanolamine (TEA), both as the free amine and as the amine hydrochlorlde. Cellulose finished with a polycarboxylic acid, such as butanetetracarboxylic acid (BTCA), has some affinity for cationic (basic) dyes. However, because of chemical and physical modification of the fibers, the finished material has virtually no affinity for anionic dyes that are normally used to dye cotton. In contrast, cotton finished with a polycarboxylic acid and certain amine derivatives has good affinity for some anionic dyes. Cotton treated with this modified finishing system can be dyed with acid, direct, and reactive dyes under specific dyeing conditions. Methods for producing dyeable, non-formaldehyde crosslinked, smooth drying cotton, as well as color strength properties of the dyed fabrics are presented. [ABSTRACT FROM AUTHOR]

Cotton fabrics crosslinked with N-methylol agents usually are resistant to dyeing. Triethanolamine, a hydroxyalkylamine, was found to be a useful additive foe improving the dyeability of crosslinked cotton with smooth drying properties. Although mono- and dihydroxyalkylamines have been shown to improve dyeability, triethanolamine treated fabric has the best dyeing properties. Dyeability of cotton containing tertiary amine was effective with anionic dyes, such as acid, direct, and reactive classes. The affinity of finished cotton for these dyes is influenced by the concentration of crosslinking agent, amine additive, and catalyst. Methods for producing dyeable smooth drying cotton and the results obtained upon variation of these components are presented. [ABSTRACT FROM AUTHOR]

Cotton fabrics, pretreated with mercerizing strength sodium hydroxide and then immersed in dilute solutions of commercially available arylsulfonium salt solutions at room temperature for one or more hours, undergo marked changes in their dye affinity. The modified fabrics are receptive to acid dyes over a wide pH range (3-9), have better affinity for direct and particularly sulfur dyes than the untreated or mercerized control fabrics, and have substantial affinity for reactive dyes at acid or neutral pH ranges (5-7). Also, the treated fabrics have affinity for disperse dyes. However, anthraquinone-based disperse dyes undergo a color shift, while azo-based disperse dyes do not when they are applied to the sulfonium-modified cotton fabrics. Quantitative (K/S) and reflectance values of the dyed samples are compared for each representative dye class. The mechanism by which the arylsulfonium salts react with cellulose has not been conclusively determined. It is probable that the reaction occurs between cellulose and one or both of the thiophenoxyarylsulfonium salts in the commercial mixture to form a stable covalently bonded structure containing a positively-charged arysulfonium species. [ABSTRACT FROM AUTHOR]

Cellulose-containing fabrics were treated with a stable pretreatment system to allow heat transfer printing with disperse dyestuffs. The pretreatment system was composed of highly methylated melamine-formaldehyde crosslinking agent, para-toluene sulfonic acid catalyst or the ammonium or magnesium salt of the acid, and amine neutralizing agent for adjusting the pH of the solution. When properly adjusted the formulations were stable for extended periods. The method of application to the fabric was by coating, padding or spraying. A thickening agent was added to the formulation for coating purposes. Both coating and spraying techniques allowed crosslinking agent to be deposited on one side of the fabric in a designated area. This was very effective for printing piece goods in which only a limited portion of the goods was heat transfer printed. Heat transfer printing of the treated material at 200°-210 °C for 20-30 seconds resulted in fabrics with high color yield and good durability to laundering. [ABSTRACT FROM AUTHOR]

Chambray cotton fabrics were produced with alkali-metal and ammonium phosphates. Yarn was treated with phosphorylating agent, cured, and woven into a fabric with the treated yarn in the filling. The fabric was piece dyed with reactive, vat, or other suitable dyes. Only the phosphorylated filling yarns were dye resistive. Other interesting effects were obtained by phosphorylating selective areas of pile fabric. Altering the degree of phosphorylation produced differential shade effects. Phosphorylated cotton also had good affinity for acid-metallized dyes. [ABSTRACT FROM AUTHOR]