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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.

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.

IN many of the industrial and other aggressive environmental conditions encountered today a synthetic, plastics‐type of paint system must be used, since traditional paints give poor and limited service. However, for these synthetic paints to be fully effective, they must be applied to more scrupulously prepared surfaces. The finer tolerances and more exacting application requirements of synthetic plastics‐type coatings, such as the epoxies, must be appreciated. Once these are understood it is not difficult to put the materials into use, where they give outstanding long‐term protection. Some of the physical, chemical and solvent‐resistance characteristics of the epoxy resin coatings can, of course, be attained with other synthetic paints, and all these materials have their place in the paint manufacturer's armoury. There are resins showing better flexibility and chemical or heat resistance than the epoxies, but the latter are outstanding in combining these and other characteristics to a marked degree—hence their fairly rapid user acceptance. There is inevitably over‐lapping in characteristics with other coatings, particularly the polyurethanes, and it is not claimed here that epoxy coatings can confer protection against all corrosive environments.

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.

Pipeline protection from Prodorife A range of coatings and lining systems designed to protect pipelines from corrosion are available from Prodorite Ltd. of Wednesbury, West Midlands WS10 7LT.

The protection of pipelines against corrosion and chemical attack requires not only the knowledge of the material carried but also of the environment of the pipeline. Pipelines may be buried in various soils or sea water etc. or be exposed to other chemical attack from surrounding chemical plant, industrial atmosphere or exposed to salt‐laden atmospheres. They may be subjected to both extremes of temperature — severe winters and hot summers. Immersed pipelines resting on or near the bottom of the sea‐bed will be subject to abrasion from sand and silt, barnacles and other fouling which can penetrate some coatings. Sulphate‐reducing bacteria are capable of corroding buried pipelines, whether steel or concrete. Protection of pipelines must therefore be carefully considered after studying all of these factors. The very high cost of corrosion of pipelines has led to the development of improved materials, application methods and inspection. The financial benefits gained are considerable — extended life, especially with abrasion resistant coatings, reduced plant shut down, reduced cost of cleaning equipment, guaranteed product purity and increased product through‐put due to reduction in frictional resistance etc.

The Protecton Special Coatings Division of Berger, Jenson & Nicholson Ltd., Portland Rd., Newcastle Upon Tyne, NE21BL, announce four new products representing further advances in the protection of exposed steelwork and concrete. They state that each has been developed to solve a practical working problem or to provide improved economy, or both.

A new pellicular column‐packing material, CO:PELL ODS, consisting of a hydrocarbon stationary phase (octadecyl silane) chemically bonded to a small impermeable glass bead, is announced by Reeve Angel Scientific Ltd, Springfield Mill, Maidstone. It is intended for use in high‐performanceliquid chromatography (HPLC), for reversed‐phase separation of non‐polar compounds including dyes, pesticides, analgesics, drugs, steroids, oestrogens, fire retardants, phenolic resins, herbicides, phthalic acid esters, vitamins, fusedring aromatics, anthraquinones, fatty acids and halogenated aromatics.

MR. JONATHAN HUTCHINSON, the eminent consultant, has just put forward a statement of the utmost importance with respect to the probable existence of a direct connection between the consumption of arsenic‐contaminated food and the occurrence of cancer. He points out that certain modern “improvements” in processes of production have led to the contamination of various food‐products with small amounts of arsenic, and observes that “if, as seems proved, the continuous use of arsenic in small medicinal doses can predispose the skin to multiple cancer there seems no reason for doubting that it may do the same for the other tissues, and for the mucous membranes and the viscera,” while there must necessarily also be “the constitutional tendency, the appropriate age, and, in some cases, the local irritation.” Mr. HUTCHINSON refers to the recent successful tracing of the Manchester outbreak of “peripheral neuritis” to the use of arsenic‐contaminated beer as an example of what may be caused by the habitual ingestion of minute doses of arsenic. It is a remarkable fact that the increase in the occurrence of cancer may be looked upon as almost synchronising with the increasingly extensive adoption of those “improved” modern methods of manufacture, not only of beer but of other food‐products, which open the door to arsenic‐contamination; together with the great increase in the use of arsenic in medical prescriptions.