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A new series of printing inks that satisfy non‐absorbent substrates, namely, metals and metal foils has been formulated. The suggested ink formulations are well adapted for the Lithographic and Flexographic Printing Processes. The inks are subjected to different testings and controllings to fulfill the requirements of printers in the graphic trade.

The special properties of the lead chromate pigments have been used for many years in surface coatings. These properties which incude high opacity and brilliance of shade need not be further elaborated here. Naturally occurring lead chromate — the mineral crocoite — when powdered and formulated in a coatings composition will darken on exposure to light. Chrome pigments were once classified according to the composition of the lead salt used in manufacture. The principal classes were:—

To synthesize some new heterocyclic disperse azo dyes and their utilization in textile printing.

To prepare 1‐cayno‐1‐substituted aryl azo‐2‐methyl benzothiazole by the reaction of 2‐aminothiophenol with malononitrile and the end product coupled with different diazonium salts. The prepared dyestuffs are established using element analysis, IR measurements, ¹H‐NMR and Mass spectra. Printing pastes containing the prepared dyestuffs and a thickener were used for printing polyester and/or nylon 6 using either transfer printing or traditional printing.

New selected arylazo cyanomethyl benzothiazole dyes were obtained from the reaction of diazotized aniline derivatives with 2‐cyanomethyl benzothiazole as a coupling component. The suitability of the prepared dyestuffs for either heat transfer printing or traditional printing on polyester and nylon 6 fabrics has been investigated. The prints obtained from dyes containing non polar groups which have sublimation properties possess high colour strength as well as good overall fastness properties if compared to those obtained using dyes containing polar groups.

The new heterocyclic disperse azo dyes were prepared from 2‐cyanomethylbenzothiazole and were utilized in preparing pastes for textile printing to print polyester and nylon 6 fabrics. In addition, the variation in substituents on the synthesized dyes could also be studied.

The method of synthesis of the new dyestuffs provides a simple and practical solution to prepare some new heterocyclic disperse azo dyes with low molecular weight, suitable for sublimation in heat transfer printing methods.

The methods for synthesis of the new heterocyclic disperse azo dyes are simple. These dyestuffs could be used in textile printing of polyester and nylon 6 on an industrial scale.

The purpose of this paper is to synthesise new heterocyclic disperse azo dyes based on benzothiazapine moiety and their printability on synthetic fabrics.

Ethyl cyanoacetate was refluxed with aniline derivatives for 3 h to form cyanoacetanilides which coupled with different diazonium salts. The products obtained were cyclised with 2‐amino thiophenol to form arylazo benzothiazapine derivatives. The structures of the new dyes were characterised by micro‐analysis as well as IR, ¹H NMR and ¹³C NMR. Printing pastes containing the dyestuffs prepared and thickened with sodium alginate were used for printing synthetic fabrics using either transfer printing or traditional screen printing.

New heterocyclic monoazo dyes derived from benzothiazabine moiety were obtained by the coupling of diazotised aniline derivatives with ethylcyanoacetate anilides followed by cyclisation with 2‐amino thiophenol. The use of synthesised dyes for transfer‐ or screen‐printing polyester and nylon 6 fabrics has been studied. The synthesised dyes which contain electron withdrawing substituents (NO₂) in the phenyl ring attached to the azo groups and electron‐donating (OCH₃) group on the other phenyl ring exert a bathochromic effect.

Synthesis of azo dyes containing benzothiazapine moiety has never been reported in textile printing.

Production of simple and less costly dyes.

Synthesis of aryl azo benzothiazapine dyes by a simple method and application in printing of synthetic fabrics.

To synthesise several new pyridine‐2(1H)thione containing an arylazo function and their applications in textile printing.

To prepare substituted 5‐arylazopyridine‐2(1H)thione by the coupling of diazonium salts of aniline derivatives with dibenzoyl methane (1,3‐diphenyl‐1,3‐propanedione) to form arylhydrazone of dibenzoylmethane which react with cyanothioacetamide in boiling ethanolic sodium ethoxide to yield the 5‐arylazo‐2(1H)‐pyridinethione derivatives. The printing properties by screen printing or transfer printing technique of these dyes are reported by using sodium alginate as thickening agent.

The structure of 5‐arylazopyridine‐2(1H)thione dyes were established and confirm for the reaction products on the basis of their element analysis and spectral data (MS, IR and ¹H‐NMR). The suitability of the prepared dyestuffs for either heat transfer printing or traditional printing on polyester and nylon 6 fabrics has been investigated. The prints obtained from dyes possess high‐colour strength as well as good overall fastness properties.

Synthesis of azo dyes containing pyridinethiole moiety has never been reported in textile printing.

Production of simple and less costly dyes.

5‐arylazo pyridine‐2(1H)thione, the result of our work aimed to define the scope of and limitation of our procedures for the synthesis of novel 5‐arylazopyridine‐2(1H)thione.

Introduction The corrosive attack of nitric acid on copper is mainly due to the nitrous acid formed by the reaction between copper and nitric acid. The reaction is conditioned by: the concentration of the acid; temperature; the presence of nitrous acid; and the solubility of the reaction products in the acid. It has been suggested that as soon as a trace of NO2 has been formed by the reaction, NO3− + 2H+ + e → NO2 + H2O, it is quickly reduced to NO2− by the reaction NO2 + e → NO2−. Then NO2− combines with hydrogen ions to give nitrous acid. Nitrous acid can readily react with nitric acid to regenerate twice the original quantity of NO2 by the reaction, HNO2 + HNO3 → 2NO2 + H2O. In each cycle the quantity of NO2 and HNO2 is doubled.

A new series of the title pyrazole azo dye systems has been synthesized. The new dyes are applied on nylon and cellulose acetate fibers to give dyed fabrics with excellent properties of colour intensity and fastness properties. The physical and spectral data of the investigated dyes are illustrated. The shifts of ultraviolet‐visible absorption maxima affected by the structural configuration of the pyrazole dye systems are investigated. The structural effects of the polyfunctionally substituted pyrazole dye systems on the intensity of colour and fastness properties of the dyed fabrics are discussed. The data of these studies are listed. The colour shades of the synthesized dyes on nylon and acetate fabrics are indicated.

The purpose of this paper is to evaluate the dyeing performance of newly designed and synthesised azo dye systems based on polyfunctionally substituted oxopyridine core for improved dyeing when applied to synthetic fibres.

For improved dyeing qualities, various azo dye systems were synthesised based on polyfunctionally substituted oxopyridine core as the coupling component. The heterocyclic moiety was coupled with diazotized aromatic amines or diazotized tetrahydrobenzothiophenes to afford the respective azo or hydrazono systems. Other counterparts were obtained via treatment with different reagents. The structure of the novel systems was elucidated based on elemental analysis and spectral data. Dyeing performance, electronic spectra and optical properties were characterised based on UV and K/S measurements. Fastness properties were also evaluated.

The novel systems were designed so that the functionalities located on the heterocyclic core afforded structure modification that led not only to good dispersion but also to improved adherence on the fibre. The sites of location led to construction of a resonating system with higher electron mobility and higher absorption maxima.

The azo dyes, used in the present context were synthesised via a step‐wise pathway leading to different systems of dyes. In addition, the variations in substituents and sites of location on the heterocyclic core could also be studied.

The novel azo dye systems based on polyfunctionally substituted oxopyridine core provide a simple practical access to a series of azo dyes with improved dyeing properties. The availability of starting materials, the simplicity and efficiency for production in good yields and high‐purity can lead to valuable achievements for commercial production.

The designed and synthesised azo dye systems could find numerous applications as disperse dyes in the fields of dyeing, printing and surface coating. Moreover, the systems could find applications as reactive dyes for wool, silk and cellulosic fibres.

The general behaviour of titanium and zirconium in pure chemical environments is summarised, and also the effects of common contaminants such as air and heavy metal ions that are present in many process streams. The beneficial effect of traces of soluble iron and copper and organic compounds in non‐oxidising acids is discussed and the relative effect of these upon the behaviour of titanium and zirconium pointed out. Information is provided upon the performance of titanium—0.15% palladium alloy under similar circumstances. The conclusion suggests that the behaviour of titanium and zirconium in various types of chemical plant is best determined by reference to in‐plant trials than by laboratory testing; the use of in‐plant corrosion probes is recommended.

Now that the paint industry has agreed with the Secretary for Prices to limit price rises to 5% for a period of six months, buyers and technologists will be actively engaged in exploring the ways by which this is to be achieved. They will expect and undoubtedly receive the fullest co‐operation from their raw material suppliers in holding down further price rises for as long as possible. The purpose of this article is to outline ways in which manufacturers of emulsion paint stainers are trying to reduce costs for the benefit of the user.