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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.

The purpose of this paper is to investigate the effects of nano‐titanium dioxide and nano‐silicon dioxide particles on the mechanical and antimicrobial properties of denture base resin.

Nano‐titanium dioxide and nano‐silicon dioxide particles were introduced to heat‐curing denture base resin to prepare composites. Electronic universal testing machine and friction tester were used to test tensile strength and frictional resistance properties of the samples prepared, respectively; also, film adhesion method was used to test the in vitro antimicrobial activity against Candida albicans and Streptococcus mutans.

Addition of nano‐titanium dioxide particles could improve the antimicrobial property of denture base resin, and addition of nano‐silicon dioxide particles could improve the tensile strength and frictional resistance of denture base resin. Mixture of the two nano‐particles, at a certain ratio, could improve the tensile strength, frictional resistance and antimicrobial property of denture base resin to a certain extent.

Nano‐titanium dioxide and nano‐silicon dioxide denture base resin composites were obtained. The mechanical and antimicrobial properties of the composites were improved compared to the raw denture base resin.

Nano‐titanium dioxide and nano‐silicon dioxide denture base resin composites with excellent performance could be obtained. Longer service life, greater hardness and clearness helped improve the patients' quality of life. Limited work with respect to the improved denture base resin was performed, which could form the theme of a future study. The outcomes of the research reported here set a new milestone in the field of denture base resin.

The purpose of this study is to evaluate the possibility of using titanium dioxide coating in the field of architectural heritage.

In this research, a titanium dioxide coating was prepared and then applied to the travertine stone surfaces. The nature of the coating was determined through various observations and analyses. Moreover, the effect of photocatalytic self-cleaning was evaluated using an organic dye (Rhodamine B).

The results of XRD, DLS and SEM confirmed the formation of small anatase crystals. The hydrophilic behavior on the surface was observed by coatings based on titanium dioxide.

The self-cleaning ability of titanium dioxide is due to the synergistic effect of its optical inductive property, which is activated with sunlight.

The self-cleaning coatings are interested for many industries. The reported data can be used by the formulators working in the research and development departments.

Self-cleaning systems are considered as smart coatings. Therefore, the developing of its knowledge can help to extend its usage to different applications.

The application of titanium dioxide coating in the field of architectural heritage is a great challenge. Therefore, in this research, a titanium dioxide coating was prepared by sol-gel method and then applied on travertine surfaces and its properties were studied.

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.

The surface character of titanium dioxide (rutile) was altered by surface modification. Silane coupling agents were used as modifiers. Physicochemical properties of the obtained products were evaluated. Effects of the modifier concentration on changes in hydrophilic/hydrophobic properties of the surface were estimated. The tendency to form primary and secondary agglomerate structures was defined using dynamic light scattering and examining morphology and surface structure with the use of scanning electron microscopy. Specific surface area and pore volume were also measured in unmodified and modified titanium white.

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.

The problems associated with preserving the steel sheeting of water‐sealed gasholders have been known for some time. Various techniques have been adopted, e.g. protective painting, oil filming and sacrificial anodes. This paper deals with painting, and the two groups of paints used in the experiments were chosen for (1) their blister‐suppressing qualities and (2) their good adhesion and water resistance.

Titanium dioxide has probably received more publicity in this last year than any other pigment used in the paint and allied industries. In a recent article, Antipov et al. in Lakokras. Mat. 1972, 4, pages 9–11, discuss a laboratory reactor that is suitable for the production of titanium dioxide by TiCl4 oxidation. The reactor has been used to investigate the temperature and residence time on the degree of dispersion and the crystalline structure of the pigment. The conditions prevailing were 700 to 1300°C, 0–20 sec. Experimental results are clearly presented using graphs.

Studies are presented which demonstrate that: (1) irradiation of titanium and zinc oxide pigments produces singlet oxygen; (2) irradiation of titanium dioxide pigments in water yields, hydrogen peroxide; and (3) the formation of singlet oxygen and hydrogen peroxide correlates with chalking tendencies of the pigments. These findings, together with the results of quenching studies, are interpreted in terms of a working hypothesis, for the generation of reactive oxidants, which ties together previous work into a unified scheme. The relative chalking rates of anatase and rutile titanium dioxide as well as the improvement of chalk resistance by surface treatment, are discussed within the framework of this scheme. The role of singlet oxygen in the chalking process, the importance of its presence with regard to the control of chalking, and possible mechanisms for its formation are also discussed.