Хром(IV) оксиді: қасиеттері және қолданылуы

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| Name = Chromium(IV) oxide
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| ImageName = Chromium(IV) oxide
| IUPACName = Chromium(IV) oxide, Chromium dioxide
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| ExternalSDS = ICSC 1310
| FlashPt = Non flammable
| PEL = TWA 1 mg/m3
| REL = TWA 0.5 mg/m3 It once was widely used in magnetic tape emulsion. With the increasing popularity of CDs and DVDs, the use of chromium(IV) oxide has declined. However, it is still used in data tape applications for enterprise class storage systems. It is still considered by many oxide and tape manufacturers to have been one of the best magnetic recording particulates ever invented.

DuPont licensed the product to Sony in Japan and BASF in Germany in the early 1970s for regional production and distribution. Japanese competitors developed cobalt adsorbed (TDK: Avilyn) and cobalt ferrite (Maxell: Epitaxial) "chrome equivalent" Type II audio cassettes and various videotape formats as substitutes. Added to that was the problem that the production of CrO2 yielded toxic by products of which Japanese manufacturers had great difficulty properly disposing. BASF eventually became the largest producer of both the chromium dioxide pigment and chrome tapes, basing its VHS & S VHS video tape, audio cassettes, and 3480 data cartridges on this formulation. DuPont and BASF had also introduced chrome cobalt "blended" oxide pigments which combined about 70% cobalt modified iron oxide with 30% chrome oxide into a single coating, presumably to offer improved performance at lower costs than pure chrome. Many high grade VHS tapes also used much smaller amounts of chrome in their formulations because its magnetic properties combined with its cleaning effects on heads made it a better choice than aluminium oxide or other non magnetic materials added to VHS tape to keep heads clean. DuPont discontinued its production of chromium dioxide particles in the 1990s. In addition to BASF, which no longer owns a tape manufacturing division, Bayer AG of Germany, Toda Kogyo and Sakai Chemical of Japan also do or can produce the magnetic particles for commercial applications.