Patent EA-000248-B1 (EA)
Title: Magnetic recording media
Inventor: LEHNER AUGUST
IPC: G11B5/733
Filed: 1996-03-18
Abstract: 1. Tape-type magnetic recording media comprising non-magnetic substrate, at least one film applied to the substrate and in at least one of these films an inorganic acicular pigment suitable for use as a supporting pigment, the ratio of the mean length to the mean diameter of the pigment being at least from 3:1 to 15:1 and the mean modulus of elasticity of the films being not less than 15 GPa in the longitudinal direction of the tape-type recording medium. 2. Recording media as claimed in Claim 1, wherein said recording media has modulus of elasticity in the longitudinal direction not less than 20 GPa. 3. Recording media as claimed in Claims 1 or 2, comprising said non-magnetic substrate and a magnetic layer intended for the information storing. 4. Recording media as claimed in Claims 1-3 comprising a layer with a binding agent and said supporting pigment. 5. Recording media as claimed in Claims 1-3 in which said supporting pigment is present in said non-magnetic substrate or in magnetic layer, intended for the information storing. 6. Recording media as claimed in Claim 3, in which layer, comprising said binding agent and said supporting pigment is arranged between said non-magnetic substrate and said magnetic layer, intended for information storing, or said non-magnetic substrate is arranged between comprising said binding agent and said support agent and said magnetic layer, intended for the information storing. 7. Recording media as claimed in Claims 1-6 in which said supporting pigment comprises ferromagnetic material. 8. Recording media as claimed in Claim 7 wherein said recording media comprises ferromagnetic metals or alloys or metal oxides as said ferromagnetic material. 9. Recording media as claimed in Claim 8 wherein said recording media comprises Fe2O3, cobalt-containing γ-Fe2O3, Fe3O4 or chromic oxide CrO2 as the supporting pigment. 10. Recording media as claimed in Claim 8, wherein said supporting pigment comprises chromium containing pigments presented as acicular particles according to formula (I) Cr<a>Ox x nH2O (I) where a is a mean chromium valence, wherein 3.0 < a <= 3.25 and in a preferable variant 3.0 < a <= 3.1 x is a number of oxygen atoms, corresponding to the chromium valence n is water content, wherein 0 < n < (4-a) / 2, at which the ratio of the mean length to the mean diameter of the pigment ranges from 3:1 to 10:1. 11. Recording media as claimed in Claim 10, wherein particles of pigments of formula (I) comprise by 50% of nucleus and by 50% of jacket, wherein value of atomic ratio of chromium in the magnetic layer to chromium in nucleus and jacket are equal. 12. Recording media as claimed in Claim 10, wherein particles of pigments of formula (I) comprise by 50% of nucleus and by 50% of jacket, wherein value of atomic ratio of chromium in the magnetic layer to chromium in nucleus and jacket greater or less than in nucleus. 13. Recording media as claimed in Claims 1-6, wherein said recording media comprises non-ferrous supporting pigments. 14. Recording media as claimed in Claim 13, said recording media comprises FeOOH or α Fe2O3 as said supporting pigment. 15. Recording media as claimed in Claim 13, said recording media comprises a compound of formula (II) Cr2O3 x nH2O (II) as said supporting pigment where n is within limits from 0 to 0.5 for which the ratio of the mean length to the mean diameter of the pigment ranges from 3:1 to 10:1. 16. Recording media as claimed in Claims 9-12 and 15, comprising non-magnetic substrate, a layer on it, comprising said binding agent and pigments of chromium-containing metal oxide presented as acicular particles with ratio of the mean length to the mean diameter of the pigment (II) being at least 7 and a magnetic layer arranged on layer, comprising binding agent and pigments, said magnetic layer intended for information storing and comprising abinding agent and ferromagnetic metal pigments, wherein modulus of elasticity being more than 15 GPa in the longitudinal direction of the tape-type recording medium. 17. Recording media as claimed in Claims 10-12, comprising pigments of particles of formula (II), oriented in the outer magnetic field.