JPS58179941A - Production of magnetic recording medium - Google Patents

Abstract

PURPOSE:To prevent the corrosion starting from a slit surface ferromagnetic metallic recording layer, by slitting a magnetic tape of a large width and giving a plasma process to the slit surface in an atmosphere containing more than one of O2, N2, NH3 and H2S to obtain a protecting film. CONSTITUTION:A ferromagnetic, metal such as Co, Cr, etc. is vapor deposited on a large-width film substrate of polyester, etc. to obtain a magnetic recording medium 3. This medium 3 is slitted by a cutter 8 into two parts, for example, in a cylindrical vacuum tank 1. Then more than one of O2, N2, NH3 and H2S gases is put into a plasma processor 9 to form a protecting film of oxide, nitride, etc. on the slit surface. The tapes 6 and 7 containing the protecting film are taken up to take-up tapes 4 and 5 respectively. In such a way, the corrosion starting from the slit surface is prevented to reduce the change with time.

Description

[Detailed description of the invention] The present invention relates to a method of manufacturing a magnetic recording medium.

It is well known that a magnetic recording medium with high coercive force and high squareness ratio can be obtained by diagonally attaching 9 ferromagnetic metals to a polymer molded material by vacuum evaporation, ionoblating, etc. .

By the way, when manufacturing a magnetic recording medium using this method, a wide strip-shaped substrate is used, a ferromagnetic metal is adhered to this substrate, and then the substrate is slendered to a width depending on the product used. are doing.

For this reason, there is no magnetic metal attached to the side surfaces of the slitted substrate, which has the disadvantage of being susceptible to corrosion.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a magnetic recording medium that improves one or more of the drawbacks and prevents corrosion of the scratch and groove surfaces.

In order to achieve the above object, the present invention applies a 01°N2. N.H.
The present invention provides a method for manufacturing a magnetic recording medium, characterized in that plasma processing is performed in an atmosphere containing at least one of H2S and H2S gases.

An embodiment of the present invention will be described below based on the drawings.

Reference numeral 1 denotes a cylindrical vacuum chamber, which is maintained at a vacuum level of about 10 Torr. 2 is a supply roller.

A strip-shaped magnetic recording medium 6 is rolled. The magnetic recording medium 6 is one in which a ferromagnetic metal such as cobalt or pm is obliquely adhered to a substrate made of a strip-shaped polymer molded product such as a polyester film, giving it characteristics of high coercive force and high squareness ratio. It is. 4 and 5 are winding rollers for winding up the magnetic recording media 6 and 7 after being slit. A cutter 8 slits the magnetic recording medium 6 sent out from the supply roller 2 into two. Reference numeral 9 denotes a plasma processing apparatus for performing plasma processing on the slit surfaces of the magnetic recording media 6 and 7 after the slits. This plasma processing device 9
Inside is 1=-Q,, N2. At least one type of gas of NH3 or H2S is introduced.

That is, after the magnetic recording medium 6 is sent out from the supply roller 2, it is sliced into two by the cutter 8, and the knot surface on which the magnetic layer is provided is exposed.

The magnetic recording media 6 and 7 after slitting are transported into a plasma discharge processing apparatus 9 and subjected to plasma processing. Therefore, a type of film, such as an oxide film or a nitride film, is formed on the slit and bottom surfaces depending on the gas in the atmosphere. At this time, A
A film is effectively formed when r or N2 is included. The magnetic recording media 6 and 7, on which films have been formed on the slit surfaces by this plasma treatment, are wound up by take-up rollers 4 and 5, respectively.

Therefore, the film formed on the groove and groove surfaces prevents corrosion, etc., and prevents deterioration of the characteristics of the magnetic recording media 6 and 7.

Incidentally, in the above embodiment, a ferromagnetic metal is attached to a substrate to form a magnetic recording medium, which is then wound around a supply roller. This substrate may be conveyed and a ferromagnetic metal may be obliquely attached thereto to form a magnetic recording medium, and immediately thereafter, slitting and plasma treatment may be performed, and the medium may be wound up using a single winding roller.

Furthermore, the slitting and thwarting may be performed in the same atmosphere as the plasma treatment.

As described above, according to the present invention, there is provided a method for manufacturing a magnetic recording medium in which corrosion from the slit surface can be prevented and the characteristics of the magnetic recording medium are less likely to change over time.

[Brief explanation of the drawing]

The figure shows a cross-sectional view of an apparatus used in an embodiment of the invention. 1... Vacuum chamber, 3,6.7... Magnetic recording medium. 8...force, ter, 9...plasma processing equipment. Patent applicant: Nichizu Capacitor Co., Ltd.

Claims (2)

[Claims] (1) In a method for manufacturing a magnetic recording medium in which a magnetic recording medium in which a ferromagnetic metal is attached to a strip-shaped substrate is slit to a predetermined width in a vacuum, after the magnetic recording medium is slit, the slit surface is o2°N2. A method for manufacturing a magnetic recording medium, comprising performing plasma treatment in an atmosphere containing at least one of NH3 and H2S gases. (2) The method for manufacturing a magnetic recording medium according to claim 1, wherein Ar or N2 is contained in the plasma treatment atmosphere.