Structure—reactivity studies of a new polyfunctional disulphide bis(ES-MCT/SES) reactive dye applied to silk

A new polyfunctional reactive dye containing disulphidebis(ethylsulphone-monochlorotriazine/sulphatoethylsulphone) reactive system has been synthesised and applied to silk. High exhaustion/fixation results have been achieved at 90 °C and pH 9. The vinylsulphone precursor of the disulphidebis(ethylsulphone) group combined with a sulphatoethylsulphone/monochlorotriazine reactive system confers a relatively high fixation efficiency for this type of polyfunctional reactive dye when compared with that of a conventional bifunctional reactive dye containing the sulphatoethylsulphone/monochlorotriazine reactive system. The results also indicate that high fastness properties were obtained for the reactive dyes under investigation.     

Synthesis and application of a hetero-bifunctional disulphidebis(ethylsulphone/monochlorotriazine) reactive dye

The behaviour of a heterobifunctional reactive dye based on a disulphidebis(ethylsulphone/monochlorotriazine) reactive system has been investigated. Relatively high degrees of exhaustion and fixation were achieved for cotton fabrics dyed with the disulphidebis(ethylsulphone/monochlorotriazine) reactive dye compared to bifunctional sulphatoethylsulphone/monochlorotriazine and/or conventional monofunctional monochlorotriazine reactive dyes. The results also indicate that the fastness properties are approximately the same for all the dyes studied in this investigation.     

Levelling properties of some reactive dyes on cellulose

The levelling properties of nine reactive dyes containing one or two sulphatoethylsulphone reactive groups or one sulphatoethylsulphone and one monochlorotriazine reactive groups have been investigated. A novel test method specifically applicable to reactive dyes has been used in order to evaluate levelling. Undyed and dyed cotton samples were simultaneously dyed in the same bath and the fractions of the additional dye fixed on each of the cotton samples were determined afterwards. A dye distribution index has been proposed that predicts reactive dye levelling according to whether the index exceeds 50% or not. The index was found to depend not only on the nature of the dyes, but also on the concentration of the dye fixed on cotton, the dyeing temperature and the salt concentration in the dye liquor. In redyeing tests the degrees of primary and secondary exhaustion and of dye fixation were measured as a function of concentration of the dye fixed on cotton. Finally a satisfactory correlation was found between the index and the classical inorganicity/organicity value of the dyes. The results also suggest that the levelling properties depend on the degree of dye aggregation.     

Optimal dyeing systems for resistance to the physical strength loss of the PLA/cotton blended fabric

In this study, optimization of disperse/reactive dyeing systems for resistance to the physical strength loss of Poly(lactic acid) (PLA)/cotton blended fabric was investigated. The blended fabric underwent a two‐bath, two‐stage dyeing process in which the PLA component of the blended fabric was dyed using two disperse dyes, followed by the cotton component being dyed with six reactive dyes containing different reactive groups—dichlorotriazine, monochlorotriazine, sulphatoethylsulphone, monofluorotriazine, monochlorotriazine/sulphatoethylsulphone, and monofluorotriazine/sulphatoethylsulphone groups. The optimal dyeing systems were established according to the fixation rate of the dyes, tear/tensile strength loss, and SEM micrographs of the fabric. To avoid the strength loss during the disperse/reactive dyeing process, the recommended disperse dyeing conditions were 110°C, pH 5 for 20 min, whereas the reactive dyeing conditions should be temperature ≤60°C and alkali concentration ≤3 g/L. In this regard, reactive dyes containing monofluorotriazine and monofluorotriazine/sulphatoethylsulphone groups were especially suitable for the reactive dyeing systems. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Dyeing of nylon 6 fabric with a bifunctional sulphatoethylsulphone reactive disperse dye

A bifunctional reactive disperse dye containing two temporarily anionic sulphatoethylsulphone groups was synthesised and applied to nylon 6 fabric by exhaust dyeing at a variety of pH levels and temperatures. A monofunctional reactive disperse dye containing one temporarily anionic sulphatoethylsulphone group was also synthesised, and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and total fixation yield under alkaline conditions. The results also indicate that the introduction of two temporarily anionic sulphatoethylsulphone groups of the bifunctional dye gave an enhancement in dyeing performance compared with that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric.     

Neutral dyeing of wool and wool/polyester blend fabrics using sulphatoethylsulphone reactive‐disperse dyes

Two models of temporarily anionic sulphatoethylsulphone reactive disperse dyes were applied to wool, polyester and wool/polyester blend fabrics at different dyeing pH. Maximum exhaustion values and colour yield were observed at pH 7. The results showed that reactive disperse dyes containing bis‐sulphatoethylsulphone reactive groups were more convenient for neutral dyeing of wool and wool/polyester blend fabrics if compared with a dye containing a mono‐sulphatoethylsulphone group. Excellent to very good wet fastness properties on all dyed fabrics were achieved.     

Study on analytical methods for quantifying the non‐adsorbed reactive dye forms in an exhausted dyebath

Reported herein are the results of an analysis of the compatibility of three methods for quantifying the non‐adsorbed forms of reactive dyes, in an exhausted dyebath, of the type monochlorotriazine/β‐sulphatoethylsulphone used in dyeing cellulosic fibres (cotton). The first method is based on spectrophotometric analysis and involves measuring the absorbance of the residual dyebath (after the dyeing process), the second is based on colorimetric analysis and involves measuring the reflectance of the dyed fabric and the third is based on high‐performance liquid chromatography. The purpose of the latter is to identify and quantify the non‐adsorbed dye forms in the residual dyebath. The calculated exhaustion values unequivocally prove the reliability and compatibility of these methods.     

Dyeing of nylon 6 fabric with a new bifunctional vinyl sulphone reactive disperse dye

A new bifunctional reactive disperse dye containing a temporarily anionic sulphatoethylsulphone and a nonionic disulphide bis(ethylsulphone) groups was synthesised and applied to nylon 6 fabric by the exhaust dyeing at a variety of pH and temperature conditions. A monofunctional reactive disperse dye containing only nonionic disulphide bis(ethylsulphone) group was also synthesised and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and fixation values at pH 6 and 120 °C. The results also indicate that the combination of temporarily anionic and nonionic reactive groups of the bifunctional dye provided great enhancement in dyeing performance compared to that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric.     

Synthesis of reactive dyes based on the bis-(N-carboxymethylamino)monoquaternary-triazine-bis-ethylsulphone reactive group. Part 1: Application to cotton cellulose

Reactive dyes containing the bis-( N -carboxymethylamino)monoquaternary-triazine-bis-ethylsulphone [bis-( N -CMA)-MQT-bis-ES] group and related derivatives have been synthesised. When boiled under mildly acidic conditions, such dyes are able to form two small vinylsulphone dye molecules through a process of 1,2-trans elimination. The bis-( N -CMA)-MQT-bis-ES dye was applied using different dyeing procedures (novel dyeing methods 1 and 2). The dyeing and soaping-off results of bis-( N -CMA)-MQT-bis-ES dye were compared with a model sulphatoethylsulphone dye applied using the conventional alkaline fixation method used for applying this type of reactive dye to cotton. The bis-( N -CMA)-MQT-bis-ES dye showed higher exhaustion and fixation values applied using novel dyeing method 2 compared with the sulphatoethylsulphone dye applied using the alkaline fixation method. The soaping-off efficiency for the large bis-( N -CMA)-MQT-bis-ES dye applied using novel dyeing method 2 was the same as that obtained for the sulphatoethylsulphone dye applied using the alkaline fixation method.     

活性染料及其真丝绸印染工艺探讨

研究了活性染料对丝绸进行染色和印花的工艺，提高了丝绸染色产品的色牢度、染深性、得色量和提升力。优选了酸浴法、中性浴法和碱浴法染色工艺条件以及印花工艺条件。指出一氟三嗪活性基优于一氯三嗪活性基，双活性基优于单活性基。国产活性染料应在溶解度、配套助剂、染料筛选等应用方面要加强研究。     

Influence of Temperature on Kinetics of Hydrolysis of Monochlorotriazine Reactive Dye

Abstract

The kinetics of hydrolysis of a commercial sample of the monochlorotriazine reactive dye was studied in an alkaline solution pH 10.9 at two temperatures, 80 and 50°C comparatively. The time dependent changes of the amounts of the active and hydrolysed forms of the dye were monitored by high-performance liquid chromatography.

The results indicate that within a defined time the pseudo-fiat-order kinetics can be considered. The rate constant of hydrolysis of the monochlorotriazine reactive dye at 80°C is about 33 times higher than at 50°C.     

Fixation of reactive dyes using radio-frequency energy

Radio-frequency (r.f.) energy has been used to increase the fixation rate of reactive dyes on cotton fabric in pad-batch dyeing. A parallel-plate r.f. applicator was used to heat batches of fabric containing reactive dye formulations. The time required for fixation of the dyes was reduced from several hours to a few minutes by heating the fabric in the radio-frequency field. Reactive dyes incorporating three different types of reactive groups, vinylsulphone, nicotinic acid, and mixed vinylsulphone/ monochlorotriazine were studied and found to be applicable using the hot pad-batch method. The colour yield and wash fastness of dyeings with the vinylsulphone/monochlorotriazine bifunctional dyes using r.f.-assisted fixation was equal or superior to those of dyeings performed by conventional cold pad-batch dyeing methods.     

Mechanism of Reaction of Proteins with Reactive Dyes:III—Reactivity of Soluble Proteins with Chlorotriazine Dyes

The reactivities of ten soluble proteins with a monochlorotriazine reactive dye were measured under various conditions and compared with those of mixtures of simple model compounds representing the reactive groups of the proteins. Both sets of results agreed wellwith reactivity curves calculated from measurements of the individual model compounds. The mechanisms of the reactions between the dye and proteins are discussed with reference to the dyeing of wool and other proteinaceous fibres.     

A novel resist technique based on secondary amines for the printing of cotton with reactive dyes

In an earlier paper we have described sulphite‐based resist printing using ink‐jet procedures. This paper describes an alternative approach to sulphite inactivation of vinylsulphone dyes by using secondary amines to inactivate fluoro‐s‐triazine dyes while maintaining the reactivity of the vinylsulphone dyes. Monofluoro‐s‐triazine reactive dyes are padded onto cotton fabrics and then deactivated by ink‐jet printing with a suitable secondary amine formulation to produce a white image on a solid ground colour after appropriate fixation and soap‐off procedures have been undertaken. A coloured image can be achieved by overprinting the resist‐printed areas with a coloured ink formulation containing a β‐sulphatoethylsulphone‐type reactive dye; such dyes form a β‐bis‐alkylaminoethylsulphone dye via reaction with the secondary amine. This latter dye ‘unblocks’ during a mildly acidic steaming process to form the reactive vinylsulphone dye, and so, unlike the monofluoro‐s‐triazine dye, is not deactivated towards subsequent covalent reaction with the cotton substrate.     

Dyeing cotton with reactive dyes under neutral conditions

This paper describes a new method to dye cotton with selected reactive dyes by long-liquor – or so-called 'exhaustion'– processes under neutral conditions. Particularly promising results were obtained with reactive dyes containing free vinyl sulphone residues. Although there are dyes on the market that contain free vinyl sulphone groups, for example, the Novacron C (Huntsman) range of dyes, many of this class contain 'blocked' vinyl sulphone residues; examples include sulphatoethylsulphone or chloroethylsulphone precursor groups, and these may be preactivated to the highly reactive vinyl sulphone form simply by a mild alkali treatment. After this activation, neutral, long-liquor dyeings can be carried out at the boil in the presence of electrolyte. This new dyeing method gave very good results in terms of overall fixation efficiency values, without the need for alkali additions.     

Mechanism of Reaction of Proteins with Reactive Dyes IV—Reactivity of Wool with Chlorotriazine Dyes*

Chlorinated wool was dyed with a monochlorotriazine reactive dye under infinite dyebath conditions. The kinetics of dyeing conformed to a composite equation derived from the Danckwerts and Hill equations for diffusion into an infinite cylinder with surface saturation. The rate constants for the reaction between the dye and the fibre obtained from this equation agreed well with theoretical constants calculated from the reactivities of model compounds and data obtained from amino-acid analysis. The relative contributions of the individual types of reactive site to the total reactivity of wool are discussed.     

Design and application of a multifunctional reactive dye capable of high fixation efficiency on cellulose

A polyfunctional reactive dye containing two dichloro- s -triazine residues linked through aliphatic amino groups via a third triazine system to the chromophoric residue has been prepared. The dye was synthesised stepwise from a specially synthesised 2,4-dichloro- s -triazine dyes. The first step is the reaction of both carbon–chlorine sites in the 'parent' dye with 2 mol ethylenediamine under selected conditions of pH and temperature; these conditions ensure that only one of the amino groups in the ethylenediamine will react to give the bis-2,4-aminoethyleneaminotriazine dye. The second step is the condensation of 2 mol cyanuric chloride with the two pendant primary amino groups. The alkylamino-linked dichloro- s -triazine dyes show very different dyeing properties when compared with those shown by the parent dichloro- s -triazine dye, which has the reactive group linked directly into the aromatic chromophore; in particular, the new dyes have high fixation efficiencies when dyed on cotton at 50 °C and the dye–fibre bond stability to boiling acidic conditions is very good.     

Dyeing properties of soya fibre with reactive and acid dyes

In order to determine the most suitable type of dye for soya bean fibre, the dyeing properties of three acid dyes and three bifunctional reactive dyes were compared. Additionally, the effect of a range of reactive groups on dyeing performance were studied, including difluorochloropyrimidine, monofluorotriazine, monochlorotriazine and β-sulphatoethyl sulphone, and of these the first was found to perform best. Irrespective of reactive group, however, the main factor affecting build-up was found to be the substantivity of the dye for soya fibre. The monofunctional reactive dyes in general were found to exhibit good wash fastness.     

Reactive dyeing systems for wool fibres based on hetero-bifunctional reactive dyes. Part 2: Investigation of dyeing properties during the dyeing cycle

The dyeing behaviour during the dyeing cycle of a Sumifix Supra dye and some other commercial reactive dyes under various dyebath pH conditions was investigated. Studies of the dyeing of wool serge fabric indicated that the diffusion properties of hetero-bifunctional Sumifix Supra dyes generally lie between those of b-sulphatoethylsulphone (Remazol dyes) and monochlorotriazine (Procion H dyes).     

Neutral-fixing reactive dyes for cotton.

Research into a new type of reactive dye based on the monochlorotriazine group is described. Reactive dyes of the 3-carboxypyridino-1,3,5-triazine type have been investigated, with a nicotinic acid leaving group, having high stability and fixation efficiency. Dyes of this type react with cellulose in a neutral bath, so widening the scope of reactive dyeing. A classification scheme for reactive dyes is outlined.