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Nanostructured titanium dioxide (TiO₂) coatings can potentially address the current surge in façade cleaning cost, maintenance and labour problems. The purpose of this paper is to investigate potential maintainability issues and design challenges concerning the effective performance of TiO₂ façade coatings’ hydrophilic properties, especially in tropical environments such as Singapore. This paper aims to establish a list of green maintainability design criteria to help minimise future TiO₂ façade coating issues when this coating is applied on commercial buildings with concrete and stonemasonry façade materials.

A mixed-mode approach that includes a literature review, site investigation, instrumental case studies and expert interviews is used in this study.

TiO₂ coatings help improve façade performance whilst offering environmental benefits to society. This study reports that green maintainability design criteria are vital requirements in designing sustainable buildings at the outset. The identified defects and issues will aid in ensuring the effectiveness of TiO₂ application in building façades.

This study acts as a foundation for future researchers to strengthen this little researched area, serves as a useful guide in preventing possible TiO₂ coating issues and promotes industry awareness of the use of TiO₂ façade coatings.

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.

Titanium dioxide was introduced as a paint pigment during the late 1920's and thirties, and these early grades were anatase. Rutile grades appeared in the forties and early fifties, but without surface treatments.

The purpose of this paper is to modify light hollow polymer microsphere (LHPM) with titanium dioxide nanoparticles (nano-TiO2) to improve its compatibility with latex and apply the obtained nano-TiO2/LHPM composite particles in external wall thermal insulation coatings.

The nano-TiO2/LHPM composite particles were prepared via vigorous stirring. The morphology and chemical composition of the produced nano-TiO2/LHPM composite particles were characterized using scanning electron microscopy, energy dispersion spectrum, thermo-gravimetric analyzer and Fourier transform infrared. The performance of this new composite coating was evaluated by checking its stability, density, radiation reflectivity, thermal conductivity and the resulting insulation temperature difference when forming coating film.

It was found that a 9:1 mass ratio of nano-TiO2/LHPM with total 10 weight per cent composite particles in the thermal insulation paint showed low density, good stability, low thermal conductivity (0.1687 W/m·K) and high insulation temperature difference (5.8°C).

The LHPM can be modified by other nanoparticles to improve its insulation performance in thermal insulation coatings.

This work provides a simple, robust, but effective approach to produce new thermal insulation coatings with nano-TiO2/LHPM composite particles.

This method for surface modification of LHPMs is novel and the modified hollow polymer microspheres could be applied to external wall insulation coatings.

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.

Making Fine Powders ‐ Extremely fine and uniform particles, of 5–50 nanometers, have been produced by a process being developed at Battelle Pacific Northwest Laboratories. Researchers have used the technique to synthesize new, highly dispersed catalysts with a high surface area. It offers a way to make other products which have improved properties: ceramic ball bearings and gears which are stronger and more durable than those available today, and pigments for paints and inks.

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.

This paper aims to design the nano-titanium dioxide (TiO₂) coating system which has superhydrophilic property, self-cleaning mechanism and antifog property as well as strong adhesion on glass substrate.

Two hydrophilic materials have been used such as TiO₂ nanoparticles as fillers and hydrophilic copolymer, Pluronic F-127 by using simple sol–gel approach. The prepared solution was applied onto glass through dip- and spray-coating techniques and then left for drying at ambient temperature.

The nano-TiO₂ superhydrophilic coating has achieved the water contact angle of 4.9° ± 0.5°. The superhydrophilic coating showed great self-cleaning effect against concentrated syrup and methylene blue where thin layer of water washes the dirt contaminants away. The nano-TiO₂ coating exhibits great antifog performance that maintains high transparency of around 89% when the coated glass is placed above hot-fog vapor for 10 min. The fog droplets were condensed into water film which allowed the transmission of light through the glass. The strong adhesion of coated glass shows no total failure at scratch profile when impacted with scratch load of 500, 800 and 1,200 mN.

Findings will be useful in the development of self-cleaning superhydrophilic coating that is applicable on building glass and photovoltaic panel.

The developed nano-TiO₂ coating is developed by the combination of hydrophilic organic copolymer–inorganic TiO₂ network to achieve great superhydrophilic property, optimum self-cleaning ability and supreme antifog performance.

The findings will be useful for residents in building glass window where the application will reduce dust accumulation and keep the glass clean for longer period.

The synthesis of nano-TiO₂ superhydrophilic coating which can be sprayed on large glass panel and cured at ambient temperature.

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 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.