Coatings, effect of titanium dioxide

Bechard SR, Quaraishi O, Kwong E. Film coating effect of titanium dioxide concentration and film thickness on the photostability of nifedipine. Int J Pharm 1992 87 133-139. 

Rosoff M, Sheen P-C. Pan abrasion and polymorphism of titanium dioxide in coating suspensions. ] Pharm Sci 1983 72 1485. Lehtola VM, Heinamaki JT, Nikupaavo P, Yliruusi JK. Effect of titanium dioxide on mechanical, permeability and adhesion properties of aqueous-based hydroxypropyl methylcellulose films. Boll Chim Farm 1994 133(Dec) 709-714. 

Pearlescent pigments contain small flakes or platelets of the mineral mica that are additionally coated with a very thin layer of titanium dioxide. The simultaneous reflection of light from many layers of small platelets creates an impression of luster and sheen. By varying the thickness of the coating on the surface of the mica particles, pigment manufacturers can achieve a range of colors for the pearlescent effect. 

Hsu ER, Gebert MS, Becker NT, Gaermer AL. Effects of plasticizers and titanium dioxide on the properties of poly(vinyl alcohol) coatings. Pharm Dev Technol 2001 6(2) 277-284. Kakinoki K, Yamane K, Teraoka R, et al. Effect of relative humidity on the photocatalytic activity of titanium dioxide and photostability of famotidine. J Pharm Sci 2004 93(3) 582-589. Sayre RM, Dowdy JC. Titanium dioxide and zinc oxide induce photooxidation of unsaturated lipids. Cosmet Toilet 2000 115 75-80, 82. 

The amount of titanium dioxide and its type affects the permeability of the coating. With increased permeability, the corrosion protection of a steel substrate is decreased. The pigment level was increased from 6.4 to 28 vol% and produced a corresponding reduction in corrosion resistance. In this study, the type and quantity of titanium dioxide did not have an effect on the adhesion of the coating to the substrate. Figure 19.8 provides the reason for this lack of effect on adhesion. In this study, a set of coatings was analyzed for their adhesion to... 

The Japanese have already conducted some experiments involving urinals. Researchers coated the ceramic of several urinals with a layer of titanium dioxide no thicker than a hiunan hair and left others untouched. After a month, the untreated urinals had yellow blotches, but the treated ones were still white. Titanium dioxide may also be a boon for hospitals. It can be incorporated into wall and floor tiles to kill bacteria on conwct. And even fastidious housekeepers may benefit. It seems that a thin layer of titanium dioxide keeps dust from sticking to chandeliers, The compound may even prove to be effective in water filters. 

Castaneda, L. (2007) Effects of palladium coatings on oxygen sensors of titanium dioxide thin films . Materials Science and Engineering B-Solid State Materials for Advanced Technology, 139(2-3), 149-154. 

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