Stock material or miscellaneous articles – Web or sheet containing structurally defined element or... – Including a second component containing structurally defined...
Patent
1995-06-01
2000-10-24
Resan, Stevan A.
Stock material or miscellaneous articles
Web or sheet containing structurally defined element or...
Including a second component containing structurally defined...
428328, 428329, 428403, 428407, 428694BA, 428694BH, 428900, G11B 5712
Patent
active
061364282
ABSTRACT:
In one aspect, the present invention concerns a process of making coated magnetic particles. According to this process, an aqueous sol of amorphous, hydrolyzed, aluminous, colloidal particles is mixed with an aqueous suspension comprising magnetic particles. The amorphous, hydrolyzed, aluminous, colloidal particles have a mean particle size in the range from about 0.5 to about 5 nanometers and an average degree of hydrolysis in the range from 1.5 to about 3. During mixing, the amorphous, hydrolyzed, aluminous, colloidal particles form a continuous, amorphous, aluminum hydrous oxide coating on the magnetic particles, wherein the coating has an average thickness in the range from about 0.5 to about 5 nanometers. The present invention also concerns coated magnetic particles. Coated magnetic particles according to the present invention comprise a magnetizable core and a continuous, amorphous, aluminum hydrous oxide coating formed on the magnetizable core. The coating has an average thickness in the range from about 0.5 to about 5 nanometers. In another aspect, the present invention concerns a magnetic recording medium comprising a magnetic layer formed on a nonmagnetizable support. The magnetic layer comprises the coated magnetic particles described above dispersed in a polymeric binder.
REFERENCES:
patent: 2085129 (1937-06-01), Stoewener
patent: 2885366 (1959-05-01), Iler
patent: 3535245 (1970-10-01), Lindquist
patent: 3696032 (1972-10-01), Haensel
patent: 4074002 (1978-02-01), Hack et al.
patent: 4133677 (1979-01-01), Matsui et al.
patent: 4229234 (1980-10-01), Krutenat et al.
patent: 4280918 (1981-07-01), Homola et al.
patent: 4309459 (1982-01-01), Tokuoka
patent: 4321303 (1982-03-01), Morita et al.
patent: 4336310 (1982-06-01), Okuyama et al.
patent: 4400432 (1983-08-01), Buxbaum et al.
patent: 4438156 (1984-03-01), Homola et al.
patent: 4512682 (1985-04-01), Mungons
patent: 4603080 (1986-07-01), Takazawa et al.
patent: 4707593 (1987-11-01), Murata et al.
patent: 4761243 (1988-08-01), Kakuishi et al.
patent: 4789581 (1988-12-01), Fukke et al.
patent: 4944802 (1990-07-01), Chagnon et al.
patent: 5029317 (1991-07-01), Kawai et al.
patent: 5039559 (1991-08-01), Sang et al.
patent: 5164259 (1992-11-01), Ishida et al.
patent: 5217804 (1993-06-01), James et al.
patent: 5229259 (1993-07-01), Yokota
patent: 5242752 (1993-09-01), Isobe et al.
Kratohvil et al. "Preparation and properties of coated uniform inorganic Colloidal Particles: I Aluminum Hydrous Oxide on Hematite, Chromia, and Titania" Advanced Ceramic Materials vol. 2 No. 4 Oct. 1987.
Farley et al., "A Surface Precipitation Model for the Sorption of Cations on Metal Oxides," J. Colloid & Interface Sci., vol. 106, No. 1, pp. 226-242 (Jul. 1985).
James et al., "Adsorption of Hydrolyzable Metal Ions at the Oxide Water Interface", J. Colloid & Interface Sci., vol. 40, No. 65, pp. 65-81 (Jul. 1972).
Wiese et al., "Adsorption of Al(III) at the TiO.sub.2 -H.sub.2 O Interface", J. Colloid & Interface Sci., vol. 51, No. 3, pp. 434-442 (Jun. 1975).
Kratohvil et al., Preparation and Properties of Coated, Uniform, Inorganic Colloidal Particles, Aluminum (hydrous) Oxide on Hematite, Chromia, and Titania, Advanced Ceramic Materials, vol. 2, No. 4 (Oct. 1987), pp. 798-803.
M. D. Sacks et al., "Thermal Decomposition of Spherical Hydrated Basic Aluminum Sulfate", Ceramic Bulletin, 63(2), 301 (1984).
J. E. Blendell et al., "High Purity Alumina by Controlled Precipitation from Aluminum Sulfate Solutions", Ceramic Bulletin, 63(6), 797 (1984).
N. F. Dyson, "New Phases in the System Al.sub.2 O.sub.3 -SO.sub.3 -H.sub.2 O at Temperatures Above 100.degree. C", Nature, 205, 385 (1965).
R. Brace, "Aluminum Hydrous Oxide Sols--I, Spherical Particles of Narrow Size Distribution", J. Inorg. Nucl. Chem., 35, 3691 (1973).
C. Lo, "A Microcalorimetric Investigation of the Thermodynamics of Formation of the HSO.sup.31.sub.4, AISO.sup.31.sub.4, and Al(SO.sub.4).sup.31.sub.2 Ions in Aqueous Solutions at Temperatures Between 25 and 70.degree. C", Analytica Chimica Acta, 139, 197 (1982).
J. W. Akitt, "Aluminium-27 Nuclear Magnetic Resonance Studies of Sulphato-complexes of the Hexa-Aquo Aluminium Ion", J.C.S. Dalton, 1226 (1972).
R. Wang, "The Crystal Structure of Alunite", Acta Cryst., 18, 249 (1965).
Truong Jack G.
Wood Thomas E.
Imation Corp.
Resan Stevan A.
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