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Cellulose monolayers have been spread on dilute solutions of Janus Red B (C. I. 26115) a cationic substantive dye (I); a monochlorotriazinyl (hot–dyeing) reactive dye (II) and a dichlorotriazinyl (cold–dyeing) reactive dye (III), under various conditions. I forms mixed films, in which the dye molecules (which are surface–active) are probably oriented between the cellulose chains. The substantivity of this dye for cellulose fibres has no apparent influence on its behaviour towards the film, thus re–inforcing previous conclusions that substantivity is largely a result of fibre morphology. II, at high pH, reacts with the film, making it relatively incompressible, but not causing much expansion. The dye, after reaction, is believed to be oriented beneath the film. III shows much more marked effects than II. With rise in pH and on standing for 24 h or more, it causes a large expansion of the film, which becomes incompressible with an immeasurably high viscosity. It is suggested that the dye molecules are in the surface, interposed between, and crosslinking, the cellulose chains, and appear to have reacted on each side of each glucose residue.

The various dyeing properties of the new reactive dyes, Diact Color C type, have been investigated. The dyes are derived by introducing CON3 groups in order to give the properties as the reactive dye for cellulose fibers, The results of this experiment are summarized as follows—a) The standard affinity of these dyes for cotton and viscose rayon at 30°C are -1.9_??_-4. lkcal/mol and -1.6_??_-3.3kcal/mol, respectively. The affinity of coloring matter decomposed in alkaline solution (Na2CO3) is smaller, while in acidic solution larger than the value of the original dyes.b) The absorption spectra in the vissible region indicate that the wave length value of absorption maxima of acidic decomposed colloring matter are shifted to long wave length from the respective values of Diact Color, and the coloring matter decomposed in aqueous NaHCO3 solution is a mixture of acidic and alkaline (Na2CO3) decomposition products.c) The rate of reaction (recognized to be 1st order) of Diact Color in water is slow in acidic solution, but fast in alkaline solution, the reaction being accelerated by increasing the temperature.d) The values of diffusion coefficient at 30°C with 5g/l NaCl are 0.13_??_0.21cm2/day, smaller than the values of acid dyes and larger than direct dyes.e) The rate of batchwise dyeing and the fastness of dyeings are similar to Procion Dye (cold type). In the case of Diact Color, however, the color of dyeings are changed appreciablly by severe washing with Na2CO3.

Procion Black HGS staining procedure outlined in the previous report was reexamined in order to make clear what the results obtained do mean about the internal structure of the fibers under observation. Washing of stained preparations with 30% pyridine-water was used as a criterion to judge whether or not the chemical fixation of the reactive dye against the fiber substance had taken place during the staining process. The conclusions reached are as follows:1. The staining of cross sections of cellulose fibers as well as Vinylon by Procion Black HGS applied under the standard operation is not of chemical nature. Therefore, the mechanism of the differential staining observed on viscose rayons cannot be different from that of other methods employing usual dyes.2. The staining found on cross sections of various protein fibers depends upon a chemical fixation, the reactive groups concerned there being of NH2-groups.

A new microscopical technique for differentiating the skin—core structure of viscose rayon fibers is described. Slide preparations mounting fiber cross sections are stained with an alkaline solution of Procion Black HGS, which is a Procion dye recently mar keted by ICI as a chemically reactive dye for cellulose fibers. This technique is found to furnish a staining entirely selective for the skin area in a simple and rapid way. Since it is well established that Procion dyes do react chemically with cellulose mole cules under alkaline conditions, it is highly probable that the differential staining pro duced by the present technique is due to a definite difference existing between the skin and the core with respect to the chemical reactivity toward the dye employed. This differentiation mechanism appears to be quite different from that which is generally accepted to be the case in the previously described techniques using ordinary dyes. Typical results are presented for several types of cellulose rayons showing various staining behaviors. It is seen that these results are in good agreement with those obtained by other stain methods. The same procedure, when applied to a variety of fibers other than cellulosics, is found to give positive staining reactions only to wool, silk, regenerated protein, and Vinylon fibers. Although most of these findings are as yet not satisfactorily explained, reactive dye staining of this kind seems to be of much promise in the field of fiber micros copy.

The effect of urea on formation and cleavage of a covalent bond between a reactive dye and cellulose has been investigated. The evidence presented is consistent with the view that urea increases the bonded dye yield by keeping the reactive dye in solution during the diffusion of the dye to its reaction site. Urea does not increase the water content of the fabric by retarding evaporation during drying; with urea, the water content of the fabric is lower. Urea can also decrease the bonded dye yield. In combination with alkali and heat, urea enhances cleavage of an ether-type dye-cellulose bond, but has only a slight effect on an ester-type bond. The over-all effect of urea on reactive dyeing is shown to depend upon the solvolytic stability of a dye-fiber bond under specific dyeing conditions.

Previously, one of the authors difined the percentage fixation of reactive dyes and proposed its new simple measuring method.In this study the definition and the measurement of this fixation were examined from the point of view of dyeing chemistry.The whole dyestuffs on the dyed cloth were assumed to consist of the dyestuff (Φ) adsorbed in the interior of fibre by the substantivity of dye and the dyestuff (σ) merely attached on the fibre. Both quantities, Φandσ, were measured separately and the results were discussed. The results are summarized as follows:1) The results calculated by Eq.1 are similar to the true percentage fixation.2) The presence of urea decreases the quantity of c6, but increases the contribution from the a-part.

The graft copolymerization of 3-O-methacryloyl 1,2; 5,6-diisopropylidene-α-D-glucofuranose (MDG) onto polypropylene fibers was carried out by the γ-ray pre-irradiation technique in the presence of oxygen. The isopropylidene groups of the glucose residue grafted on the copolymer were removed by hydrolysis in aqueous formic acid, and the hydroxyl and hemiacetal groups were regenerated. The deacetonated fibers exhibited a considerable affinity for water vapor and could be dyed with a reactive dye.

A new technique for staining the skin of viscose rayon cross sections is described, where Procion Black HGS, a sort of dyes marketed by ICI as chemically reactive dyestuff for cellulose fibers. is used combined with urea and soda ash. The technique is found to furnish a staining entirely selective for the skin area without requiring any particular differentiation procedure.This staining may be of great significance practically as well as theoretically, since it depends upon a chemical reaction between the dye and cellulose, i. e. upon a mechanism quite different from that of other usual dye techniques.The same staining procedure has been applied to other fibers, not only cellulosic, but also protein as well as synthetic. Interestingly enough, it has been found that wool fibers show a bilateral staining, while Vinylon exhibits a skin-core type differentiation.

The equilibrium adsorption of commercial Procion Brilliant Red 2BS by acid-modified cellulosie fibres and by standard cellulose altered by the specific action of different oxidising agents is studied. The equilibrium adsorption by all the fibres decreases rapidly in the initial stages of the action of acid, but tends to level off with further hydrolysis. The extent of the decrease depends mainly on the rate of removal of the hydrolysable fraction and the extent of crystallisation of the cellulose chains during the action of the acid. The reduction in dye uptake is more marked when primary alcoholic groups are converted into carboxyls than when secondary alcoholic groups are similarly oxidised.

Since it was introduced, the flash-ageing process has been modified by the introduction of acetaldehyde sulphoxylate as the reducing agent, to overcome the difficulties of handling and of plant design associated with the low stability of sodium hydrosulphite. The universally used reducing agent for vat printing is sodium sulphoxylate formaldehyde, but this is insufficiently reactive for use in the flash-ageing process as originally operated. It has now been shown that, by the incorporation of a suitable reduction catalyst into the print paste, sodium sulphoxylate formaldehyde can be sufficiently activated to render it suitable for use in flash ageing. This paper reviews the steps in the investigation leading to the use of such a catalyst. If the sodium sulphoxylate formaldehyde is incorporated in the vat print paste and the catalyst in a caustic alkaline padding liquor, vat-dye discharge styles can be produced by flash ageing. This process can be extended to the fixation of a reactive dye background in the same flash-ageing process as the fixation of the vat illuminating pigments.

N-Sulfonylethylenimide (1) and N-(β-chloroethyl)sulfonamide (2) are easily convertible to each other by the action of hydrochloric acid and alkali as follows:(2) Also, (1) gives β-alkoxyethylsulfonamide (3) in the presence of alcohol and alkali;(3) Therefore, the dye having (2) in the molecule can be converted into (1) by the action of alkali and this is expectable to have chemical binding with cellulose fibers. As the diazo component of (2) type azo dyes, N1-Q-chloroethyl-sulfanilamide (4), 4-methoxy-3-aminobenzenesulfonyl-β-chloroethylamide (5), 4-methyl-3-aminobenzenesulfonyl-β-chloroethylamide (6), 6-methyl-3-aminoben-zenesulfonyl-p-chloroethylamide (7), and 6-ethoxy-3-aminobenzenesulfonyl-β-chloroethylamide (8), respectively, were syntnesized as given in the following order:(A=H, CH3, OCH3, OC2H5) Then, a series of dye were synthesized, using (4) as a diazo component, and G acid, R acid, H acid, J acid, and r acid as azo component. The dyes thus obtained combined with cellulose fibers in the presence of alkali (sodium hydroxide, sodium carbonate and sodium bicarbonate) with heating and confirmed that the (2) is useful as a functional group of the reactive dye.

Reactive dyes of the Procion and Remazol types react with glucose or celobiose in alkaline solution to give predominantly dye glucosides. Therefore the previous publications, claiming a direct chemical proof for a covalent bond between the alcoholic cellulose hydroxyl groups and the reactive dye by means of identifying a degradation product with a synthetic one from dye and free sugar are not reliable.

Reactive dyestuffs containing a sulphofluoride group are fixed on cellulose by a covalent sulphonic ester linkage. Experimental evidence for this conclusion is afforded by the exchange of such a reactive dye for iodine by treatment of the dyed cellulose with NaI in acetone. This reaction is specific for sulphofluoride dyes.

Gaseous and volatile materials, produced from the pyrolysed natural fibers (cotton, wool and silk) under various conditions, were analysed qualitatively and quantitatively by the mass spectroscopy. The following conclusions were deduced: 1) The products were containing H2, CO2, lower hydrocarbons and others. 2) The amounts of produced gas were not recognized a great deal of difference among the sorts of natural fibers. 3) At the range of 300°C and 800°C, a hydrogen cyanide increased as the temperature raised, but ammonia and acetic acid reached to the maximum amount at about 400°C and decreased with a more increase in temperature gradually. 4) It was indicated that a hydrogen cyanide was produced more easily in air than in N2, gas atmosphere. 5) A CO gas was not recognized a great deal of difference in amount among the natural fibers. 6) Comparing about the dyed and the not dyed one by reactive dye, it was supposed that the components of the pyrolytic products were affected by dyeing.

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.

The manipulation of the physical characteristics of nonwovens and paper by variation of fiber and web geometry is briefly reviewed in terms of a new system of bonding in which the adhesive interfiber forces are a consequence of ionic chemical bonds. These bonds were created by the sequential covalent introduction of anionic sites onto the interior and exterior surfaces of microporous pulp and rayon fibers using a chloro-s-triazinyl fiber reactive dye and subsequent stoichiometric reaction with crosslinking polycations derived from ethylenimine. The tensile properties of both the pulp and rayon fiber assemblages were significantly augmented as a result of the development of both ionic inter- and intra-fiber bonds.

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.

Work on the application of chlorotriazinyl reactive dyes to wool is reviewed. It is shown that, under the hot acidic dyeing conditions that must be used to obtain satisfactory dyeings on untreated wool without the aid of solvents, the fixation, and hence the wet–fastness properties, is limited by the absorption of hydrolysed dye. The possibility of applying dichlorotriazinyl dyes to shrink–resist–treated wool under alkaline conditions and at low temperatures is discussed. The application to wool of dyes containing acrylamido groups is considered in detail. This group does not hydrolyse in the dyebath. Consequently, very high levels of fixation to the fibre can be attained under appropriate conditions, and the relation between fixation and fastness to severe wet treatments is demonstrated. The mechanism of the reaction of acrylamido dyes with wool has been studied. Reactivity towards model compounds in solution suggests that reaction with primary and secondary amino groups and with thiol groups is the principal mechanism of their reaction with wool, and the importance of amino groups is also indicated by the relative reactivity of an acrylamido dye towards wool, silk, and nylon. Amino–acid analyses of wool dyed to heavy depths with unmetallised and 1: 2 metal–complex acrylamido dyes show that reaction takes place predominantly with the –amino group of lysine residues, there being no evidence of reaction with the thiol group of cysteine nor with histidine residues. Preliminary work with a chloroacetyl reactive dye suggests that this group reacts with both cysteine and histidine residues.

A novel type of fiber reactive dye is described which eliminates chloride, alkoxide, or arylovide ions to produce a dyed fiber in which the amino groups of the fiber constitute a part of the chromophoric system. 3-Chloro-, 3-alkoxy-, and 3-aryloxy-Δ 1.α-indenemalononitriles and Δ1,2'-indene-1,3-indandiones had weak absorption maxima below 300 nm and dyed cellulose ester and polyester fabrics had pale yellow-orange shades. Dyeings on nylon 66 resulted in displacement of the 3-suhstituents by the amino groups of the fiber to give intense violet or blue dyeings. These compounds are members of a new class of fiber-reactive dyes.

The covalent nature of the bond between a reactive dye and the cellulose molecule has been proved by means of microbiological degradation of the dyed cellulose and identification of glucose in the hydrolysate of a dyed soluble degradation product.