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Sulphur dyes are the most highly consumed colourants for cellulosic substrates owing to their reasonable cost and acceptable fastness. However, the use of noxious conventional reducing agent, sodium sulphide and impaired wash fastness against oxidative bleaching is gradually decreasing the market of these dyes. As the need for “Green” goods and services is raising public awareness, this paper aims to use a glucose-based biodegradable reducing agent in place of sodium sulphide to dye cotton fabrics with a range of commercial sulphur dyes. The study also proposes an aftertreatment method to improve the fastness properties of the dyeing.

The paper investigated the impact of a newly developed aftertreatment method on the fastness properties of dyeing. This involved the sequential application of a cationic fixing agent (Tinofix ECO) and tannin (Bayprotect CL) on the coloured fabrics and subsequent evaluation of colour strength, washing, light and rubbing fastness.

The effect of aftertreating the dyed cotton was found to significantly improve the light and wet rub fastness. The surface morphology of the dyeing remained unaffected as depicted by the absence of any finish residues.

The protective effect of the cation–tannin aftertreatments was examined with a view to providing the necessary commercial performance; however, it was established that the dry rub fastness was either reduced or remained unaffected and the wash fastness to International Organization for Standardization 105 C09 was also marginal.

This finishing technique is novel and can be found useful for manufacturing sulphur-dyed products with the improved light and wet rub fastness.

While the interest in alternative metalization processes for the manufacturing of printed wiring boards is extremely keen, the long‐term reliability of plated through holes fabricated with these electroless copper alternatives remains in question. However, during the last three years, significant process improvements have been made in the direct metalization process based on a patented dispersion of graphite. This paper will describe the technology in detail and present data on the reliability and versatility of the graphite based direct metalization process.

Since world attention has been focussed on the quality and safety of drugs, thought is being given to improving the methods of dealing with this branch of control under the Food and Drugs Act, 1955. This work is entirely different to the several projects now being undertaken, such as the Government‐sponsored “safety committee” dealing with the clinical testing of new drugs before sale; this deals mainly with toxicity trials, therapeutic efficiency and adverse reactions and is designed to prevent such catastrophies as the recent drug‐induced deformities of babies. The recently proposed scheme of the Association of British Pharmaceutical Industry for an advisory centre had similar objectives.

Cationic dyes exhibit high exhaustion towards protein fibres, such as wool and silk, due to ionic interactions but they show little substantivity onto cellulosic and hemicellulosic fibres. In order to apply cationic dyes to mill scoured and bleached linen fibers, a new approach employing anionic agents containing a reactive monochloro-S- triazinyl group is synthesized and used to import a negative charge to the fibre surface.

Two cationic dyes show considerable substantivity towards anionic agent modified fabrics. Four different anionic agents are covalently bounded to the linen substrate to provide an electrostatic interaction with cationic dyes. The anionic agent treated fabrics are monitored for nitrogen content, and the reaction efficiency is determined as a K/S value of the dyed samples.

Different factors that affect the pretreatment and dyeing process are investigated, and an overall improvement in the effectiveness of the anionic agent on the dyeability using cationic dyes is achieved. The reaction efficiency for the four anionic agents follows the order: anionic agent III > I > II > IV > untreated fabric. The treated dyed fabrics also exhibit good fastness properties.

An all‐latex binder system has been developed by Revertex which is said to overcome many of the problems associated with previous binder systems used for coating paper and board. It is a two part mix, and is known as the AB system. Blending the latices in varying ratios with a pigment dispersion will give the required rheological behaviour for different processes. The first part is a specially formulated primary latex binder, and the second part is activated by alkali and modifies the viscosity.

Sulphur dyes provide an inexpensive medium to dye cellulosic fibres with heavy shade depths. They offer moderate to good fastness to light and wet treatments. However, owing to the environmental hazard produced by the use of sodium sulphide, the practical implication of these dyes is steadily decreasing. Moreover, these dyes are prone to oxidation causing pronounced fading on exposure to laundering. This paper aims to present the green processing of sulphur dyes by using a biodegradable reducing agent in place of sodium sulphide to dye cotton fabrics. The study also proposes after-treatments with tannin to improve the fastness properties of the dyeings.

In this study, dyeings were produced on cotton fabric with a range of C.I. Leuco Sulphur dyes, which were reduced with sodium sulphide and glucose. Sulphur dyeings were after-treated with an environment-friendly tannin-based product (Bayprotect CL (BP)); subsequently, the after-treated samples were evaluated for colour strength, wash, light and rubbing fastness.

A novel after-treatment method was developed, which substantially improved the wash fastness of C.I. Leuco Sulphur Black 1 dyeing to ISO 105 C06/C09 washing. However, the degree of this improvement varied for the other sulphur dyes used. The surface morphology and the possible mechanisms for the improved fastness properties were also discussed.

The effect of after-treatment was significant for improving the wash fastness of sulphur black dyeings in particular, while the effect on other colours was minor. Significant improvements were observed for light and wet rub fastness for most of the dyeings, which signifies the importance of tannins as a finishing agent.

It is observed that the tannin-based product, BP, is found to provide the photoprotective effect by improving the lightfastness of the dyeings. Future research may involve the exploration of various tannins as a finishing agent to sulphur dyeings.

This novel finishing technique is found significant for improving the wash fastness of sulphur black 1 dyeings for both the reducing systems. Improvements were also observed for light and wet rub fastnesses for most of the dyeings.

It is common practice to classify film forming systems into chemical and physical drying types. The drying of a film former by chemical means results in a film that is either largely or completely insoluble in the original solvent in which it was dissolved. Physical drying of a film former produces a film which may be re‐dissolved in the original solvent. Emulsion polymers do not fit precisely into this scheme, for although physical processes are involved in the film formation, the final film is not soluble in the original medium, i.e. water.

In recent times, wool- and silk-blended fabrics are popular for creating glamourous products. Silk is blended to wool for creating more lustrous effect and to impart strength; on the other hand, wool is responsible for resilience, softness and warmth properties. Chemically both the fibres are protein-based, but the amount of amino acids is different. Due to this, the dye absorption behaviours of the two fibres from the same dye-bath are different. Wool is become darker than the silk fibre, if both the fibres are dyed together in a single bath dyeing process.

Here the wool fibres are first pre-treated with a commercial synthetic tanning agent (syntan) Mesitol HWS at three different pH values of 2.2, 3.2 and 4.2 and at three different concentrations: 5, 10 and 15 per cent. Then the syntan pre-treated wool fibres are dyed together with silk fibres maintaining the blend ratio as 80:20 by Telon Red MR, Telon Yellow M4GL and Telon Blue MRLW with sodium sulphate at three different concentrations of 10, 20 and 30 per cent.

The dye absorbency of the syntan-treated wool fibres decreased with increase in syntan concentration, whereas the colour strength of silk fibres increased. The resist effectiveness of wool fibres is increased from 6 to 59 per cent with increase of syntan concentration. So after the dyeing process, the colour strength of syntan-treated wool fibres are almost same with the colour strength of silk fibres. The washing fastness of the samples is improved, and wash fastness behaviour of both wool and silk fibres is almost same.

This paper gives an idea about the one bath dyeing process of wool- and silk-blended fabrics to achieve solid dyeing effect.

Nylon 6 fabric is pretreated with tannic acid and subsequently dyed with a cationic dye, Rhodamine B, from an aqueous dye solution and emulsion phase. The emulsion phase of n-hexadecane is emulsified by isopropyl alcohol and stabilized by Rhodamine B/tannic acid complex. Different factors affecting pretreatment and dyeing process have been studied. Changes of moisture regain, tensile strength, elongation and binding stiffness of the pretreated fabric are investigated.

The FTIR spectra of tannic acid pretreatment of nylon are also examined. The pretreated fabric with 10% owf tannic acid shows a slight increase in the tensile strength and elongation percentage. A higher moisture regain and binding stiffness are observed with increases in the amount of tannic acid. The results also indicate that the pretreatment for cationic dyed nylon 6 fabrics with tannic acid promote a higher dye uptake and cationic dye-based emulsion system with better fastness properties relative to those of the dye solution based system. A further improvement in wet fastness is secured by an aftertreatment of all dyed fabrics with a commercial anionic fluorescent whitening agent, Uvitex^® RSB 150%.

This paper deals with the formulation of colloidal graphite lubricant for special applications by the use of nonionic wetting and dispersing agents. The lubricant was stable for 5–6 months and met the other requirement of the specification for such lubricants. In conclusion some suggestions are made which might help in increasing the long term stability of the product.