Polishing Compound

Titanium IV) oxide, T1O2. See titanium dioxide. Dissolves in concentrated alkali hydroxides to give titanates. Mixed metal oxides, many of commercial importance, are formed by TiOj. CaTiOj is perovskite. BaTiOa, per-ovskite related structure, is piezoelectric and is used in transducers in ultrasonic apparatus and gramophone pickups and also as a polishing compound. Other mixed oxides have the il-menite structure (e.g. FeTiOj) and the spinel structure (e.g. MgjTiO ). 

Calcined aluminas are also used for polishing appHcations by mixing into polishing compounds in the form of paste or suspensions. Polishing aluminas are used to alter the surfaces of metals, plastics, glass, and stones in the manufacture of cutlery, automobiles, computers, furniture, eyewear, semiconductors, and jewelry. Polishing aluminas are also used to coat surfaces, such as video tapes (1). 

Chalk is a calcium carbonate prepared by precipitation. It is used in many polishing compounds including dentifrices. 

Aluminum is produced commercially by the electrolysis of cryolite, Na3AlF6, but bauxite, A1203, is the usual naturally occurring source of the metal. The oxide is a widely used catalyst which has surface sites that function as a Lewis acid. A form of the oxide known as activated alumina has the ability to adsorb gases and effectively remove them. Other uses of the oxide include ceramics, catalysts, polishing compounds, abrasives, and electrical insulators. 

Uses. For pencils, refractory crucibles, pigment, lubricant, polishing compounds, electroplating... 

Co. of California. Proven orebody reserves at the end of December 1978 were 365,000 metric tons, with indicated reserves of over 3 million metric tons of rare earth oxide (REO). Current mine production capacity is 27,000 metric tons per year of bastnaesite concentrate produced in 3 grades a 60% REO unleached concentrate, a 70% REO leached concentrate (SrO and CaO removed), and a 90% REO calcined concentrate (CO2 removed). In 1977, shipments totaled 13,521 metric tons of contained REO. Polishing compounds consumed approximately 10% of this production. 

With suitable chemical, mechanical and heat treatment, glass polishing compounds of high quality have been produced from bastnaesite concentrates since 1965. 

The free world market for cerium-oxide based polishing compounds is not large—approximately 4400 metric tons per year—, and we do not see a substantial growth potential despite the 11% annual growth in sales of spectacle lenses. The reason is twofold first, faster more efficient polishing compounds are available which can be used in slurry concentrations one-half that of a few years ago second, fully half the market for ophthalmic glass lenses has been captured by plastic lenses of CR-39 polymer. Cerium oxide is ineffective in polishing this material specially treated alumina or stannic oxide are used. 

The estimated end-use pattern for cerium oxide based polishing compounds in the U.S. (1979) is illustrated in Table II. 

TABLE II. ESTIMATED END USE PATTERN IN THE UNITED STATES FOR CERIUM-OXIDE BASED POLISHING COMPOUNDS (1979) a... 

This fraction after calcination can be used directly as a glass polishing compound. 

Stannic oxide (cassiterite) is used as a polishing compound for both glass and metal. It is also used to produce milky or colored glass and is used in the formulation of fingernail polish (Windholz 1983). 

There is a large class of processes where the final product is an emulsion. It includes homogenized milk, shampoos, polishing compounds, and some types of medical preparations. A key factor is the chemistry of the product, to ensure that the emulsion remains stable over a desired product shelf-life, when produced properly by the fluid mixer. There are numerous correlations in the literature on drop size in a two-phase liquid-liquid system, relative to fluid properties and mixer variables. However, most... 

Bleaching and polishing compounds Aerosols Anticorrosive coatings... 

Although AI2O3 is the source of aluminum in the Hall process for obtaining the metal, it is a very useful material in its own right. Activated alumina is used as an adsorbent for many gases and is effective in their removal. Alumina is also an important constituent in abrasives and polishing compounds, catalysts, ceramics, and electrical insulators. 

Tooling surfaces such as mold cavities and die openings require meeting certain surface finishes. Rather than identifying the required finish as dull, vapor-honed satin, shiny, etc., there are standards such as a diamond polishing compound, SPI (originally SPI/SPE) Mold Standard Finish, and American Association s standard B46.1 Surface Texture (extremely accurate surface measurements a near-perfect system) that are used. This ASA B46.1 corresponds to the Canadian standard CSA B 95 and British standard BS 1134. 

Because of the accelerated polish rates and increased smoothness observed with ceria, ceria is often used as a polishing compound in glass polishing. However, because oxide CMP evolved from CMP of silicon for the preparation of wafers, the silica abrasive used for silicon CMP has been utilized almost exclusively for oxide CMP. One study by Jairath et al., however, examines the use of ceria in oxide CMP. Figure 5.12 compares the oxide polish rate vs. normalized polishing stress (a function of velocity and pressure) between a slurry of fumed silica abrasive and a slurry of ceria plus silica abrasives. As expected, the polish rate with the ceria slurry is greater (approximately 3 times) than the polish rate with the silica slurry. 

The nonfood uses of rice bran oil are feed formulations, soaps, and glycerin. Waxes may be used as a camauba wax replacement in confectionery, cosmetics, and polishing compounds products. 

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