Magnetic recording medium

Patent 4950555 Issued on August 21, 1990. Estimated Expiration Date:

January 9, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Process for production of ferromagnetic powder
Patent #: 4063000
Issued on: 12/13/1977
Inventor: Aonuma , et al.

Process for production of magnetic recording medium
Patent #: 4354909
Issued on: 10/19/1982
Inventor: Takagi , et al.

Magnetic recording medium
Patent #: 4382110
Issued on: 05/03/1983
Inventor: Takagi , et al.

Recording media comprising vertical magnetization layers essentially consisting of quaternary Co--Ni--Zn--P alloys
Patent #: 4517257
Issued on: 05/14/1985
Inventor: Shimizu , et al.

Magnetic recording medium
Patent #: 4582746
Issued on: 04/15/1986
Inventor: Shirahata , et al.

Silane dispersing agent for magnetic media
Patent #: 4597801
Issued on: 07/01/1986
Inventor: Stratta , et al.

Magnetic recording medium Patent #: 4599280
Issued on: 07/08/1986
Inventor: Izumi , et al.

Inventors

Assignee

Denki Kagaku Kogyo Kabushiki Kaisha

Application

No. 294998 filed on 01/09/1989

US Classes:

428/900MAGNETIC FEATURE

Examiners

Primary: Thibodeau, Paul J.

Attorney, Agent or Firm

Oblon, Spivak, McClelland, Maier & Neustadt

Foreign Patent References

73411 JP. 06/12/1981
212118 JP. 12/12/1983
2153852 GB. 08/12/1985

International Class

G11B 023/00

Foreign Application Priority Data

1986-05-27 JP

Abstract

A magnetic recording medium is disclosed, which comprises a substrate having provided thereon a magnetic substance which is composed of an alloy comprising cobalt, phosphorus and at least one member selected from the group consisting of thallium and elements of group Vb of the periodic table, and optionally at least one member selected from the group consisting of nickel and zinc. The magnetic recording medium exhibits a high coercive force, squareness ratio and a high output with a small noise.

Other References

IEEE Transactions on Magnetics, vol. Mag-6, No. 3, pp. 503-506, Sep. 1970)
Electronics Symposium, pp. 549-552, (May 1967), "Recording Characteristics of Thick Cobalt-Zinc-Phosphorus Films"
Patent Abstracts of Japan, J58-212118A, Hitachi condenser
Kinzoku Hyomen Gijutsi (Metal Surface Technique) Takano et al., vol. 31, 1980
J. Electrochem. Soc., Morrison, vol. 6, No. 11-12, pp. 419-427
J. Appl. Phys., Mahbub, Apr. 15, 1985, pp. 4026-4030
Maeda, "High Coercivity Co and CoN: Alloy Films", J. Appl. Phys., 53(5), May 1982, p. 373