strikes. At yearend, some categories of iron oxide pigments were in short supply, owing to inventory depletion due to the dock strikes. Iron oxide was used as a pigment in paints, rubber, plastics, concrete products, paper, magnetic ink, and fertilizers. It is used also in ferrite applications such as television components, filters in radio equipment, computer memory cores, door latches and seals, small electric motors, and in ductor and microwave devices. Iron oxide material is used also in miscellaneous applications such as abrasives, welding rod coatings, soil conditioners, foundry sands, and automobile brake linings. Data are not collected by the Bureau of Mines on specific uses of iron oxide pigments, and the figures given in table 2 do not necessarily reflect all sales of iron oxide pigment material for uses except as pigment. Table 2.-Finished iron oxide pigments sold by processors in the United States, by kinds Table 3.-Prices quoted on finished iron oxide pigments, per pound, in bags, unless otherwise noted, as of December 31, 1971 1 1 Low and high range covers prices for car lots and less than car lots, at the works. 2 Barrels. Source: Oil, Paint and Drug Reporter and American Paint Journal. FOREIGN TRADE Despite the adverse effects of dock strikes, the 10-percent tariff surcharge, and monetary revisions, total imports of iron oxide pigments into the United States in 1971 increased 11.7 percent to 36,496 short tons compared with 32,684 short tons in 1970. The value of iron oxide pigments imports in 1971 increased 6.9 percent to almost $6.2 million contrasted with about $5.8 million in 1970. Manufactured iron oxide pigments made up the major portion of total imports. Crude and refined umber constituted the bulk of natural iron oxide pigments imports. West Germany, Canada, and the United Kingdom supplied the bulk of manufactured iron oxide pigments, while Spain provided the major supply of natural pigment imports. Exports of iron oxide pigments from the United States in 1971 decreased 1.3 percent to 3,984 short tons, contrasted with 4,565 short tons in 1970. However, the value of exports of iron oxide pigments increased 0.4 percent to $1.7 million compared with $1.6 million in 1970. Canada was the destination of the major quantity of iron oxide pigments exports in 1971. Table 4.-U.S. exports of iron oxide and hydroxides, by countries, 1971 Table 5.-U.S. imports for consumption of selected iron oxide pigments Classified by the Bureau of the Census as "Natural iron-oxide and iron-hydroxide pigments, n.s.p.f." Table 6.-U.S. imports for consumption of iron oxide and iron hydroxide Natural iron oxide pigments reportedly have been replaced in many applications by synthetic iron oxide pigments.2 However, the natural pigments are still being used, and some grades are assured an expanding market in future years. In competition with other pigments, iron oxide will continue to be used because of its cheapness, permanence, and availability. The development of alkyd and polyester resins formulated with black iron oxide pigments and carbon black was reported to be a significant step in the process of applying paint by electrocoating.3 These materials electrodeposited on a metal surface act as conductive primers, enabling a second coat to be deposited. Normally, only one coat of paint can be applied by this method; 2 Industrial Minerals. Iron Oxide Pigments. No. 50, November 1971, pp. 9-19. American Paint Journal. A Review of the Paint Industry for 1970. V. 56, No. 1, July 26, 1971, pp. 55-59. therefore, it has been used mainly for primers and undercoatings. A Soviet patent (No. 220,478) covered powder coatings that can be made to adhere to a surface more securely by incorporating in them a powdered iron oxide or iron. After application of the coating, the object is magnetized, attracting the ferromagnetic powder and increasing the adhesion of the coating. East German patent 66,240 also described paints that are made magnetic by incorporating powders of ferrous materials. A possible source of ferric iron oxide was described in a U.S. patent.5 Bayer process red mud was reacted with sulfur dioxide to precipitate ferric iron oxide. Iron oxide-based cassette recording systems reportedly are almost as good as chromium dioxide cassettes and are com parable to regular audio-tape recording systems. However, both chromium and iron oxide systems may soon face market competition from metal powder systems which offer very low tape speed and greater miniaturization. A nonmagnetic, black iron oxide pigment, which has high temperature resistance and is nonfloating and flocculating, was introduced recently in West Germany. It has good dispersibility. The pigment can be used for electrocoating paints as well as decorative and silicone paints. American Paint Journal. V. 56, No. 12, Oct. 11, 1971, p. 71. 5 Tsai, J. H., Chemical Precipitation. U.S. Pat. 3,574,537, Apr. 13, 1971, 2 pp. Chemical and Engineering News. Du Pont Challenged on Magnetic Tape. Feb. 21, 1972, p. 12. American Paint Journal. V. 56, No. 11, Oct. 4, 1971, p. 71. |