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Coal‐tar pitch, either in its simple form or as part of more complicated formulations, is being increasingly used in modern times for the heavy‐duty protection of steelwork, concrete, non‐ferrous metals, etc. wherever the utmost in resistance to corrosion is required. Wailes Dove Bitumastic Ltd., of Hebburn, Co. Durham, have been specialists in coal‐tar pitch compositions for over 100 years and are in the vanguard of research to extend its possibilities to keep pace with modern needs for corrosion prevention. This report traces the development of coal‐tar pitch from its use as a simple, single material to its use in the most modern and advanced type of coatings.

Demands for coatings with superior technical characteristics have induced the use of composite coatings, which usually represent an extremely strong product. The resin blend technique is a simple and useful method for improving paint properties. Coal tar resins are the most economical coating extensively used in the industry; short oil‐length alkyd resins are usually used for air and force‐dry industrial coatings for metal surfaces. The purpose of this paper is to evaluate coating blends composed of these resins, in particular, the effects of short oil‐length alkyd additive on the properties of coal tar binder.

One way to achieve new types of binders is to make combinations of the existing ones, in an ideal case retaining the desirable properties of both. The alkyd has important properties over the original drying oil. To achieve the goal of improving coal tar resin properties, short oil‐length alkyd was blended with it. The prepared short oil‐length alkyd was characterised using IR and ¹HNMR spectroscopy. The mixing ratio of short oil‐length alkyd with coal tar was up to 25 per cent. The compatibility of coating blend was characterised by scanning electron microscope. The physical, mechanical and chemical properties of the coating blend in addition to the corrosion resistance were determined according to ASTM methods.

In spite of a large number of synthetic resins being available for use in paint formulations, the alkyd resins surpassed all of them in versatility and low cost. The blend of short oil‐length alkyd resin with coal tar has yielded better coating blend properties. The coating blend showed significant enhancement of physical, mechanical and chemical properties such as gloss, drying time, adhesion, scratch hardness, acid and solvent resistance because the coating blend combines the properties of thermosetting and thermoplastic resins.

Alkyd resins are the most extensively used synthetic polymers in the coating industry. Modification of coal tar blend based on other type of polyester resins could also be studied in order to assess the applicability of the coal tar blend system found for other applications.

These types of alkyd resins can be applied in other bitumen composites as additives and reinforce agent.

The paper shows how the low‐cost modified coal tar binder can be used for air and force‐dry industrial coatings for metal surfaces.

The X‐ray diffraction patterns of epoxy resins: four samples with different epoxide equivalents and coal‐tar blended epoxy resins: three samples with different epoxide equivalents were recorded using CuKa X‐ray radiation. These X‐ray diffraction patterns were indicating the amorphous nature of the resins. Their intensity curves were subjected to Fourier Analysis for the first time in order to get more information about the difference between epoxy and coal‐tar blended epoxy resins in terms of their internal structure such as particle size, percentage crystallanity and electron density fluctuations. Also, the effect of different epoxide equivalent on these physical parameters was interpreted successfully in epoxy as well as coal‐tar blended epoxy resins.

All anti‐corrosive coatings have a common role of protecting the substrate to which they are applied.

After more than six years of operation carrying the hottest crude oil in the North Sea, the anti‐corrosion system of the Phillips Ekofisk pipeline is free from submarine decay. For the 212‐mile line, which stretches from Norway to Teeside, is protected with 120/5 glass‐reinforced coal tar enamel from Metrotect Ltd., of Cleckheaton, Yorkshire.

The parameters for Quality Control of both the anti‐corrosion coating and, where required, concrete weight coaling, are reviewed for six major pipelines in which the authors have been directly involved. The importance of field joint anti‐corrosion coatings are discussed, particularly for concrete weight coated pipelines. The differing environment of each project is identified and includes “in‐service” temperature, water depth, mode of pipe lay, together with cathodic protection considerations. The importance of quality control is traced from initial design study to coating and includes practical aspects of on‐site quality assurance. Material selection, application, inspection, safety aspects and economics are discussed.

Discusses the particulation of organic barrier layers, based on laboratory‐bench data, obtained from the exposure of painted panels in low, high or neutral pHelectrolytes. It also discusses their compatibility with the succeeding and preceding layers and the galvanic interactions at the layer substrate interfaces. Aspects like substrate effect, leaching of the micaceous iron powder, role of high temperature and hydrodynamic disturbances and distribution of ultrafine particulates have been highlighted using potential versus time plot, AAS data, and galvanic current measurements and XRD analysis. Exposure tests conducted under ambient conditions and under very strong hydrodynamic disturbances, revealed superior properties of the SiC particulated epoxy based barrier layers.

ALL ‘plastics’ are generally divided into two groups: the ‘thermoplastics’, which are formed by heating, can be re‐heated after forming, and re‐formed almost ad lib, such as celluloid, xylonite, rhodoid, cellophane, and perspex; and the ‘thermosetting plastics’, which are also formed by heating but cannot yet be re‐formed by the application of heat or any other means, probably the best‐known example of which is the thermosetting variety of bakelite.

Phenols‐furfural resin (analogous to novolake type phenol‐formaldehyde) was obtained from condensation reaction between cotton straw powder and phenolic product in presence of an inorganic acid. The optimum conditions for resin formation were confermed by infrared spectra and its characteristics were determined.

Ever since the Ancient Britons painted themselves with woad for protection from the weather, the use of paint as a protective coating has continued to expand. Today the range of products is so wide that only a few can here be selected for description, as a general guide to the properties and types of paint to be found among those marketed under thousands of different trade names and reference systems by Britain's 600 or more manufacturers. This article therefore seeks to give representative examples of the types of paint now available.