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One of the problems with curing films containing a titanium pigment with ultraviolet light is the rapid attenuation of the incident light by the pigment. This limits both the pigmentation level and the thickness of film that can be effectively cured. In this study, the transmission by thin pigmented films of light of wavelength in the range 320–400 nm is measured experimentally. It is shown that the massive absorption of both the rutile and anatase forms of titanium dioxide in this region is responsible for the rapid attenuation of the light used to cure the films. The principal conclusion is that, given a constant lamp intensity and photoinitiator efficiency, the larger the wavelength of the light used to cure the film the greater will be the thickness of film that can be cured.

The development of new protective organic coatings is affected by a number of factors, the most important ones at present being those related to environmental acceptability of anticorrosive pigments. An effective solution has been shown to be the application of anticorrosive inorganic pigments based on mixed metal oxides. These pigments consist of spinel and rutile lattice structures. In order to examine the anticorrosive properties, the individual pigments prepared were added to alkyd and styrene‐acrylate based test coatings. Both the anticorrosion efficiencies, and the mechanisms of action of the pigments were also evaluated.

Over the last fifteen years, acrylic resins have become more widely accepted for use in surface coatings. Acrylic resins may be divided into two main categories, solvent‐borne and water‐borne systems. Solvent‐borne solution polymers may be subdivided into two groups: thermoplastic and thermosetting resins. Basically a thermosetting resin is built up from monomer units selected to give the degree of hardness and flexibility required. They may be self‐crosslinking, but usually require the addition of a crosslinking agent, a reactive bifunctional monomer unit, that serves to crosslink and insolubilize the copolymer. Other monomers may be introduced to confer specific properties and many commercial thermosetting acrylic resins contain four or more different units in the chain.

Over the last 50 years the element titanium has been steadily gaining in importance. The major interests range from titanium metal, which combines good resistance to corrosion with high strength and low specific gravity, to the white pigment, titanium dioxide, and titanium tetrachloride, a chemical intermediate. This paper reviews the manufacture of these materials and particularly deals with the properties and applications of titanium dioxide, which, by reason of its high refractive index, possesses outstanding lightening and hiding power, making it the first choice among white pigments.

Titanium dioxide pigments have been produced commercially for eight decades. The industry has seen many developments from the humble beginnings with uncoated, impure, anatase pigments to the highly refined TiO₂ pigments of today. For the past four decades there have been two commercial routes for making TiO₂ pigments ‐ sulphate and chloride. In recent years, significant efforts have been made to produce TiO₂ by both routes with greater environmental awareness. To compare the overall impact of TiO₂ manufacturing processes on the environment, life‐cycle assessments of several process options are described in this paper.

The behaviour of light in white prints is dominated by the presence of titanium dioxide pigment, which is responsible for opacity. The pigment also strongly influences gloss and is responsible for the whiteness of prints.

The purpose of this paper is to investigate the anticorrosive effects of a new pigment based on bulk of talc covered with a surface layer of titanium dioxide.

The new pigments were characterized using different analytical and spectro‐photometric techniques. Characterization of these pigments using X‐ray diffraction, scanning electron microscopy and transmission electron microscopy. The energy‐dispersive X‐ray analysis technique was used to assure the presence of titanium dioxide on talc surface, then X‐ray fluorescence (XRF) was employed to elucidate the concentration of different elements in the prepared pigments. Evaluation of these pigments was undertaken using international standard testing methods. The pigments were then incorporated in solvent‐based paint formulations based on medium oil alkyd resin. The physico‐mechanical properties of dry films and their corrosion properties were tested using accelerated laboratory tests in 3.5 percent NaCl for 28 days.

The results of this work reveal that as the layer of titanium dioxide is increased in thickness, enhanced anticorrosive properties of the new pigments are obtained.

These pigments can be applied in other polymer composites, e.g. rubber and plastics, as a reinforcing agent.

These prepared pigments are environmentally friendly and impart high anticorrosive behavior to paint films, a unique homogenous texture, and deliver concomitant cost savings.

A dry pigment is, as such, a material of limited interest. A well dispersed pigment is, however, a highly appreciated material. Between the dry pigment and the dispersed pigment lies the process of pigment dispersion. The dispersion process is therefore of prime importance for pigment users.

Paper is coated mainly to improve its aesthetic appeal and its printability. The pigmentation of these paper coatings is just one of several interlocking factors that influence the final print quality. Other main features include optical uniformity which is related to gloss, and geometrical uniformity which is related to smoothness and printability. Apart from the actual pigments used, print quality is also influenced by the coat weight, see Fig. 1. In general the pigments that print the best are those with the worst flow properties in suspension. This in turn is related to pigment packing since bad packing gives poor flow properties (Fig. 2). Good printability is related to good compressibility. Softer lattices are more compressible and consequently give better printability. There is also a relationship between pigment type and size with coating porosity and uniformity, which in turn is related to other factors such as ink scuff, mottle and blistering, etc. which give poor print quality.