Titanium Dioxide-Based Pigments

This pigment is said to be bifunctional. It combines corrosion protection and light scattering in a single pigment [5.95]. It is recommended for application in water-and solvent-borne primers as well as in cathodic electrodeposition coatings and coil coatings [5.95]. The typical properties of this anticorrosive are summarized in Table 5.12. 

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The aim of this investigation is to examine the effect of nucleating agents on factors such as crystallization onset temperature and spherulite size. The nucleating potential of titanium dioxide based pigment and that of regranulated process waste is also examined since a knowledge of such effects is essential if process and product consistency is to be achieved. 

The addition of 0.5% titanium dioxide based pigment to FINA 5060S (un-nucleated) is sufficient to increase its crystallization temperature by 7°C and its crystallization rate fourfold. Spherulite size also reduced from 27 microns to 15 microns at this level of addition. 

In the 5 years that followed (1965-70), three additional producers—American Potash, National Lead, and Pittsburgh Plate Glass—opened chloride-process plants. Sales of composite titanium calcium-base pigments continued to drop, as they had done over the previous 5 years in which Du Pont had ceased to produce them. This was due primarily to their adverse effect upon the stability of latex systems and the rapid replacement of alkyd and oleoresinous flat wall paints by flat latex paints. Two so-called "maximum-durability" pigments were introduced during this period—one by Du Pont and the other by National Lead. These pigments, although produced by different methods, both essentially eliminated the photochemical reactivity of the base titanium dioxide. 

Titanium dioxide white pigment based on the rutile modification is mainly used for PP due to its high refractive index of 2.8. ZnS and ZnS/ BaS04-based lithopone pigments are also used due to their low hardness and abrasivity, e.g. in glass reinforced PP types. 

The three main groups of commercial complex inorganic color pigments are titanates, which use a titanium dioxide base, aluminates, which use an aluminum oxide base, and chromites and ferrites, which have chromium and/or iron oxide bases. Some important complex inorganic color pigments are listed in Table 3.4. 

Chem. Descrip. Di(octyldodecyl) fluoroheptyl citrate Uses Emollient, pigment dispersant for pigmented prods., titanium dioxide-based sunscreens, eye shadow, creams, lotions, geis, pharmaceuticals Improves slip and feel on skin heips create water barrier moid reiease agent for lipsticks and other stick prods. 

Titanium whites resist various atmospheric contaminants such as sulfur dioxide, carbon dioxide, and hydrogen sulfide. Under normal conditions they are not readily reduced, oxidi2ed, or attacked by weak inorganic and organic acids. Titanium dioxide dissolves slightly in bases, hydrofluoric acid, and hot sulfuric acid. Owing to its chemical inertness, titanium dioxide is a nontoxic, environmentally preferred white pigment. 

Pigment Dispersion. The alkan olamines and thek derivatives are useful in dispersing titanium dioxide and other pigments (209). Monoisopropanolamine and triethanolamine are particularly effective in aiding titanium dioxide dispersion in the production of Ti02 and in water-based paints (210). The alkan olamines are also an aid in the grinding of titanium dioxide (211). 

Titanium dioxide is a common pigment, and zinc oxide and magnesium oxide are common fillers in rubber base adhesives. 

Fletcher A new process proposed for making titanium dioxide pigment from ilmenite, based on its dissolution in hydrochloric acid. Developed by Fletcher Titanium Products, a subsidiary of Fletcher Challenge, a large paper company in New Zealand, based on original... 

Organic surface treatments, on titanium dioxide pigments, 25 26 Organic syntheses, 13 412—113 acid and base catalysts for, 24 182 advantages of fermentation over, 11 6 enzymes as catalysts for, 10 307 high pressure in, 13 438—139 ozone use in, 17 810-811 silylation in, 22 695-696 Organic tellurium compounds, 24 414-415, 422... 

It promotes adhesion of intaglio inks to the polypropylene surface. An acrylic based primer is a good choice because of its ability to effectively bond water-based inks. Dry powder form of acrylic primer is diluted with methyl ethyl ketone and xylene (each component is mixed in equal parts by weight). To create the opaque surface, 5wt% titanium dioxide pigment is added to the solution. 

Primer Formulations. Coatings were formulated using standard techniques. Mill bases were prepared by dispersing the oligomer solution with pigments (silica, carbon black, titanium dioxide and barium sulfate in a 1 1 1 10 ratio). The viscosity of the formulation was reduced to spray viscosity by addition of solvent. 

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