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Kaolin is a soft, white mineral mainly composed of coarse‐ to fine‐grained, plate‐like aluminum silicate particles. As kaolin assists with desired rheological properties that help maintain proper dispersion and provide bulk to the product, it is used as an important extender in paint manufacture. It can be used to reduce the amount of expensive pigments, such as titanium dioxide. In spite of these uses, kaolin has the disadvantage of having coarse particles and low hiding power. The purpose of this paper is to introduce a new class of pigments based on kaolin as a core and titanium dioxide as the shell.

In the work reported in this paper, kaolin was used as a core covered with a surface layer of titanium dioxide comprising the shell in order to combine their properties and get over kaolin's disadvantages, besides enhancing its corrosion protection properties. The pigments prepared were characterised using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Deposition of titanium dioxide on the surface of kaolin was confirmed by Energy‐dispersive X‐ray analysis (EDAX) and X‐ray fluorescence (XRF) techniques. Pigment properties were estimated according to American standard testing methods (ASTM) methods and then were incorporated in anticorrosive paint formulations based on medium oil alkyd resin. The physico‐mechanical and corrosion properties of dry paint films were determined according to ASTM methods.

The tests revealed that the concentration of titanium dioxide layer deposited on kaolin surface was inversely proportional to the anticorrosive behaviour of these pigments.

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

The pigments prepared are eco‐friendly that can replace other expensive pigments. These pigments can compensate for the presence of titanium dioxide in paint formulations successfully, and thus lower the costs. The main advantage of these pigments is that they combine the properties of both of their counterparts, they are of lower cost, and they also overcome the disadvantages of both its counterparts, e.g. low hiding power of kaolin, photochemical activity of titanium dioxide. Also, they can be applied in other industries other than paints, e.g. paper, rubber and plastics composites.

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.

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.

Reports on tests in which barium metaborate pigment and its modified form are prepared, identified by chemical and X‐ray diffraction methods, and specified according to standard methods. Evaluates the modified barium metaborate as a new filler for paper making by carrying out two series of experiments. Details the results which showed that the efficiency of the filler retention when using modified barium metaborate was higher than that of the other two conventional fillers. Reveals that at relatively low filler addition (2–5 percentage weight), higher improvement in the strength properties can be obtained when using the modified pigment instead of titanium dioxide and kaolin, but observes the reverse (i.e. a detrimental effect) at relatively high filler addition (8–10 percentage weight). Discovers that the optical properties of the modified pigment‐loaded sheets lie between those of titanium dioxide and kaolin. Shows that blending barium metaborate with kaolin or titanium dioxide has a significant effect on strength properties rather than optical properties. Concludes that modified barium metaborate pigment can be successfully used in paper filling applications and that modified barium metaborate pigment‐kaolin blend (80/20 per cent) can be used instead of titanium dioxide as a paper filler.

Titanium dioxide, the chemically‐based product commonly referred to as white pigment or as titanium pigment, or in the industry, often simply by its chemical formula, TiO2, is not a single substance but is actually a broad range of quite different performance products. Because each one is designed to accomplish defined technical purposes in specific applications, they are not generally interchangeable with other applications. While both producers and users of these various TiO2 pigment products refer to them as grades of TiO2, this unfortunate nomenclature masks the performance distinctions of individual titanium dioxide products. Thus some people, and even some producers who should know better, mislabel titanium dioxide as a commodity. Focusing on the fallacy of the commodity assumption is important to understanding the global outlook for the business for users, producers, and investors.

In this study, titanium white was investigated, covered with aluminium oxide and silica. The titanium white was produced by Chemical Works Police S.A. under the catalogue symbol of R‐210. Surface of titanium white was modified with silane coupling agents, such as 3‐methacryloxypropyltrimethoxysilane (A‐174), vinyltrimethoxysilane (U‐611) and N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane (U‐15D). The unmodified and the modified titanium white was subjected to physicochemical analysis. Moreover, tests were performed aiming at defining morphology, surface structure, and dispersion of the particles as related to, first of all, the type of applied modifier. Product evaluation took advantage of modern investigative techniques, including SEM and DLS. Modified and unmodified titanium whites were applied as pigments in acrylic paints. The modified Titanium dioxide in particular improved strength and utility properties of studied paints.

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 pace of technical development in the paint industry is seemingly nowhere more rapid than in the field of raw materials, with almost every issue of paint journals containing reports of new products and details of their practical application. In truth many of these new materials are comprised of nothing more radical than standard products with slight changes in some minor detail, but at the other end of the spectrum are those materials which are so novel that whole new avenues of research are opened up. Wherever any new product is placed on the broad spectrum of novelty however, there is no doubting that many new opportunities are constantly being created for paint chemists to utilise. This series of articles will consider some of the literature that has appeared in the technical press in the last three years, and will cover recent developments in the technology of pigments and extenders, convertible and non‐convertible media, as well as solvents and additives. It is hoped that these reviews will enable paint chemists to take full advantage not only of the new products which have recently appeared on the market, but also heighten their awareness of new approaches to formulating with established raw materials. This first article is concerned with colouring pigments which here have been split into two broad categories of white and spectral colours. Later articles will consider developments in anti‐corrosive pigments and extenders.

Various types of ionic and non‐ionic dispersants have been classified by their ability to stabilise titanium dioxide pigment suspensions in water. It was found that some non‐ionic dispersants produced suspensions that exhibited full steric stabilisation as opposed to electrosteric stabilisation that occurs with ionic dispersants. A high level of steric stabilisation was found to relate to greater flocculation resistance in both the wet and dry phases, which can result in improved paint stability and higher opacity.

There are many methods by which the state of dispersion of pigments may be studied, either in the liquid paint or in the dried film. They range from essentially practical methods useful for production control to sophisticated laboratory techniques capable of providing quantitative data on the number, size, and type of particles present in a dispersion.