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The synthetic reaction of rosin‐modified phenolic resin used as a vehicle for offset inks was studied. The two‐step synthetic process to feed resol by dropping was adopted to control the formation of methylene quinone, which was derived from the dehydration of hydroxymethyl phenol. The methylene quinone could react with rosin and vegetable oil to form dibenzopyran cyclic product by Diels‐Alder reaction. The dibenzopyran cyclic product was favourable for raising the molecular weight and the mineral oil tolerance of the modified resin.

In order to obtain desired film properties, alkyd resins are frequently modified by other resins and polymers either by physically blending them or chemically incorporating them. Some of the recent physical modifications of alkyd have already been described in the first part of the article. In this second part, the different types of resins and polymers used for the chemical modifications of alkyd resin are reviewed. A critical discussion on generally recognised advantages and disadvantages of the resultant coating from each modifier is described. Their use in surface coating industry are enumerated. Types of modifier to be used for improving a particular property in the coating are also suggested.

Hard resin such as Rosin modified moleics. Rosin, modified phenolics and Aromatic hydrocarbon resin petrez SP 100 (source IPCL) were dissolved in mineral turpentine (50% solids) and their films were applied on the glass pannels (10cm × 3cm × 0.5cm) to give a WFT of 3 mils. The loss of solvent from the film was studied at an interval of 10 minutes till the weight of film was nearly constant at ambient temperature.

Seventy paints were prepared, based on six grades of laboratory prepared barium metaborate pigments. The paints could be classified into three groups according to the type of the binder; each group comprises seven sub‐groups. The paints were tested first in the laboratory and then in actual environment (above and under sea water). Commercial barium metaborate (Busan 11‐M1) based‐paints were prepared and used as a blank.

Twenty seven formulations were prepared based on three grades of laboratory prepared silver pigments. These formulations could be classified into three main groups. The aim of this classification is to study the effect of the type of binder and pigment on the efficiency of the formulated electric conductive paints. A commercial silver conductive paint is used for comparison. The formulated paints were laboratory tested for adhesion, hardness, acid and alkali resistance, corrosion protection and electric conductivity. It has been found that these formulations pass all the laboratory tests. The conductivity of the formulated paints is higher than the conductivity of the commercial one. Both of the pigment particle size and the type of the used binder effect the conductivity of the formulated paints.

ABM Chemicals Ltd is exhibiting its range of photosensitisers for uv curing including the Glocure benzoin ethers. These highly cost effective materials ensure maximum utilisation of uv energy for the polymerisation process.

Barium metaborate as a new less toxic anti‐corrosive pigment was tested for protection against corrosion in an atmospheric exposure testing station set in Egypt on Alexandria seashore. Seventy paints were prepared, based on six grades of laboratory prepared barium metaborate pigments. The paints could be classified into three groups according to the type of the binder; each group comprises seven subgroups according to the pigment grade used. The paints were tested first in the laboratory and then in actual environment. Commercial barium metaborate (Busan 11‐M1) based paints were prepared and used as a blank. High corrosion protection properties are obtained for up to nine years exposure. Results showed that mixing barium metaborate pigments with neutral binder gave better results than mixing them with acidic binder. Laboratory prepared pigments gave better results than the commercial one. It was also found that corrosion protection of these pigments increases with the increase of pigment modification.

The purpose of this paper is to study thermal stability, curing kinetics and physico‐chemical properties of polyurethanes systems for application in in‐mould decoration (IMD) ink.

The thermal stability of three Polyurethane (Pu) systems A, B, C were evaluated by thermogravimetric analysis (TGA). The kinetic parameters of the curing reaction of Pu system C were calculated using non‐isothermal curing kinetics analysis, including the activation energy Ea, the reaction rate constant K(T), the reaction order n, the initial curing temperature (Ti), the peak temperature (Tp), and the finishing temperature (Tf). Additionally, physico‐chemical properties were also evaluated such as flexibility, impact resistance, pencil hardness, adhesive attraction and solvent resistance.

TGA showed that thermal decomposition temperature T5 (5 wt.% weight loss), T10 (10 wt.% weight loss) and Tend (decomposition termination temperature) of Pu system C was 344°C, 363°C, and 489°C, respectively. T5, T10, Tend increased by 77°C, 61°C, 4°C, respectively, and the char yield at 600°C increased by 25.1 wt.% comparing with Pu system B. Curing kinetics analysis showed that Ea of Pu system C was 62.29 KJ/mol, 65.98 KJ/mol and 65.95 KJ/mol by Kissinger, Flynn‐Wall‐Ozawa and Ozawa method, respectively. The order of the curing reaction (n=0.90) demonstrated that it was a complex reaction. Moreover, Pu system C exhibited good physico‐chemical properties. The results showed that Pu system C was suitable to apply into IMD ink.

The TGA analysis, curing kinetics analysis and evaluation of physico‐chemical properties provided a simple and practical solution to study suitable resins for IMD ink application.

IMD ink for heat transfer printing technology is highly efficient, relatively low cost, clean and environmentally safe. It has been widely applied into medical and pharmaceutical products, electronic devices, telecommunication equipment, computer parts, appliance panels, automotive parts, etc.

In this paper, the thermal stability and curing kinetics of Pu for IMD ink are reported for the first time. The paper gives very interesting and important information about thermal stability, curing kinetics and properties of Pu coating system for IMD ink application.

Summary The present work aims to study the inhibition mechanism of barium metaborate pigments. Six grades of barium metaborate pigments were prepared in the Laboratory of Polymers and Pigments, National Research Centre of Cairo, Egypt. The methods of preparation modification and evaluation is the main subject of a recent article. The pigments were incorporated, with other ingredients, into formulations, and the electrode potential, electrical resistance, water uptake and weight loss measurements were taken. Formulations based on a commercial pigment supplied by an international company were prepared and used as blanks.

The most important component of a coating is the resin: all other components simply modify the resin. Solvents affect the flow, pigments give decorative effects and aid economy; the physical and chemical properties of the resins used are the principal differences in various paint systems