JPS6038727A - Magnetic recording medium and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a thin film type magnetic recording medium havng an overcoat layer with superior wear and corrosion resistances by forming an org. plasma-polymerized layer contg. silicon on a magnetic layer so that the refractive index is adjusted to a specified value or above. CONSTITUTION:A support 10 having a magnetic metallic (alloy) film vapor-depodited on a polyethylene terephthalate film is sent from a sending reel 11 in a sending chamer 3 to a winding reel 13 through an electric discharge chamber 2. In the chamber 2, a mixture of a compound contg. silicon such as vinyltrimethoxysilane with O2, N2 and H2 as plasma-nonpolymerizable gases is fed from small holes in the edge of an upper electrode 6 to the chamber 2 through the slender pipe of the electrode 6, gaseous Ar or the like is sent from inlets 14 as required, and high frequency power is applied to a lower electrode 7 to form an evercoat layer of an org. plasma-polymerized substance contg. Si and having >=1.45 refractive index on the magnetic film. The thickness of the overcoat layer is 20-1,000Angstrom . Thus, a magnetic recording medium having a small spacing loss and superior traveling performance without reducing the reproduction output is obtd.

Description

Detailed Description of the Invention (a) Industrial Application Field: The present invention relates to the improvement of magnetic recording media, and particularly to thin-film magnetic recording media with improved runnability, abrasion resistance, and corrosion resistance of the overcoat layer. Regarding.

[b) Prior art: If magnetic recording media are classified in terms of the method of forming the magnetic layer, (1)
) Thin film type and (2) coating type.

A thin film magnetic recording medium has a magnetic layer formed on a support by a method such as vacuum evaporation, sputtering, ion blasting, or plating of a magnetic material.

A coated magnetic recording medium has a magnetic layer formed by coating a support with a magnetic paint made by adhering magnetic powder with a binder. In this coated magnetic recording medium, the actual filling rate per unit volume of the magnetic layer is low due to the content of the binder. Furthermore, since the spacing loss between the magnetic head and the magnetic head increases, the reproduction output decreases.

On the other hand, thin-film magnetic recording media have a high effective filling rate of magnetic powder in the magnetic layer, but the corrosion resistance of the magnetic layer is low, and it comes into contact with magnetic heads, guide rollers, etc. during running, and is prone to scratches. easily and cause noise. It also has the disadvantages of a large coefficient of friction, poor running performance, and weak mechanical strength.

In order to improve the above-mentioned drawbacks of thin-film magnetic recording media, vacuum deposition, sputtering,
Overcoating methods such as ion blating have been used.

That is, ■ Metals such as rhodium and chromium, W%TiO2,
High hardness inorganic substances such as CaF2 and yigF2: A method of overcoating a lubricating organic substance such as metal soap using a vacuum deposition method: ■ A method of overcoating a lubricating organic substance layer using a coating method: ■ Applying a prepolymer liquid After that, the coating film is irradiated with ultraviolet rays or electron beams to cause a polymerization reaction to form an overcoat layer: ■ JP-A-57-167132, JP-A-57-16713
No. 3, Publication No. 57-167134, the nitride film and oxide film are overlaid by plasma treatment of nitrogen gas or oxygen gas ions or these gases on the magnetic layer. Coating method: ■ Announced at the 1986 IEICE Semiconductor/Materials Division National Conference, and published in the proceedings of the same conference r11175 (19
As shown in 81), it is known to overcoat a cobalt film (magnetic layer) with a plasma polymerized film made of an organosilicon monomer.

However, the vapor deposited films and coating films formed by the above methods and (2) have low film strength. In particular, in the case of (2), it is difficult to form a thin film using a polymer coating film, which causes a spacing loss between the film and the magnetic head, resulting in a reduction in reproduction output.

Furthermore, it is difficult for the coated and cured layer formed by the method (2) to maintain the 41-coat lubricity for a long period of time. The nitride film and oxide film formed by method (2) are difficult to satisfy in terms of running stability.

Further, although the overcoat film obtained by the method (2) has good corrosion resistance, it has the disadvantage that the overcoat layer must be thick in order to improve wear resistance. As a result, the spacing loss between the magnetic head and the magnetic layer increases,
The disadvantage is that the playback output is small. In this regard,
For example, in 1977, the Optical Society of America
a) Published academic journal “Abrid Optenox J”
(Applied Optics) Volume 16 & (No. 3, No. 71) Articles from pages 1 to 721 [Plasma Volumarized Coating Fobolycarbonate: Single Layer, Ablation Resistance, and Anna Reflexicon J (Plasma
polymerized coating for
polycarbonate: single 1ay
er+ abrall-ion resistant+
and antireflectio++) Middle D,
It has been reported that oxygen glow discharge on the surface of a hynyltrimethyloxysilane film increases the number of 5i-0 bonds (411 degrees) and changes the degree of crosslinking during polymerization, which can increase surface hardness and abrasion resistance. If so, it can be predicted that the various physical properties of the polymer film will change.

However, there is still no known method for reliably determining the degree of crosslinking of a polymer film from changes in physical property values.

The present inventors have discovered that as the degree of crosslinking in polymerization increases, the refractive index will inevitably change, and by using a polymeric film with a high refractive index as an overcoat, it is possible to create a magnetic recording medium with high wear resistance. Various studies have been conducted based on the assumption that a magnetic recording medium having an overcoat layer of a plasma polymerized film with a refractive index of 1.45 or more is a magnetic recording medium having an overcoat layer with a refractive index of 1.45 or less. We have discovered that the coefficient of kinetic friction and still life, which will be described later, are dramatically improved compared to media, and we have developed the present invention.

[c] Object of the invention: The object of the invention is to provide a thin film magnetic recording medium having excellent running properties, wear resistance and corrosion resistance/ζ overcoat layer.

Another object of the present invention is to provide a method for manufacturing such a thin film magnetic recording medium.

(d) Structure of the invention: The first object of the invention is to provide a magnetic layer and an f.
In a magnetic recording medium having an overcoat layer formed on an n-type layer, this can be achieved by constructing the overcoat layer with a silicon-containing organic plasma polymerized layer having a refractive index of 1.45 or more.

The composition of the silicon-containing organic plasma polymerized layer with a refractive index of 1.45 or more, which constitutes the overcoat layer formed on the magnetic layer of the magnetic recording medium according to the present invention, is as follows: (1) The plasma polymerized layer mainly contains silicon. If it is composed of (St), K, carbon (C), oxygen 0), and hydrogen (compound), the composition ratio of carbon to silicon (C/St) is 0.1 to 2.0.
, the oxygen composition ratio (0/St) is preferably 1.0 to 3.0.

OAlso, the plasma polymerized layer mainly contains silicon, carbon, oxygen,
If it is composed of nitrogen and hydrogen, the composition ratio of carbon, oxygen, and nitrogen to silicon is 0.1 to 2.0, respectively.
:0.1-2.0: It is preferable that it is 0.1-2o.

Preferred compositions of the silicon-containing plasma polymerized layer include:
For example, co, as4(o11Sio5t: co
44) 1o31Q0.32SiO,21: C0,20
1 (0,08Q0.05Si0.67: C0,37
) (0,02QolsSio4s: Co, +aHo
,osQo4eSio33:Co,os)loo2Qo
,5zSio,as: C0,111(0,03Q0
．． 41NO,11Si0.34: C0,0500,
4ONo3oSio, 2s: Co, o7Qo32N
o2aSio3a: Co, 52Hoj.

()o,t5NO,273i0.162CO,21)1
0.08Q0.18NO,263i0.27:C0,1
3J(o, oaQo, a5So, +t3io33, etc.).

The plasma-polymerized layer does not need to contain any silicon compound at all, and the film thickness is preferably in the range of 20 to 1.00 OA, and particularly preferably in the range of 100 to 500 OA.
'A range. If the thickness is less than 20X, it is too thin and has no effect as an overcoat layer, and if it exceeds 1,000X, the spacing loss between the magnetic layer and the magnetic head is too large, resulting in a reduction in reproduction output.

The silicon organic plasma polymerized layer can be formed not only on the upper surface of the magnetic layer, but also on the surface of the support opposite to the surface on which the magnetic layer is formed, and by this method, "warping" of the support can be prevented. can.

Further, if necessary, a 411 slip layer may be formed on the upper surface of the silicon-containing organic plasma polymerized layer.

In the method for manufacturing a magnetic recording medium according to the present invention, after forming a magnetic layer on a support, a silicon-containing compound and a non-plasma polymerizable gas are simultaneously subjected to plasma polymerization treatment on the magnetic layer. This is achieved by overcoating a silicon-containing organic plasma polymerized layer with a refractive index of 1.45 or more.

The plasma polymerization treatment of a silicon compound and a non-plasma polymerizable gas in the method for manufacturing a magnetic recording medium according to the present invention includes:
Any polymerization method called plasma polymerization method may be used, but a silicon-containing compound gas and, if necessary, other compounds or argon (Ar),
A preferred method is to polymerize an inert gas such as neon (Ne), introduce it into a reaction space, cause a gray discharge in this space, and deposit it on the magnetic layer on the support.

Gases of silicon-containing compounds used in plasma polymerization include monosilane: disilane: tetramethylsilane: vinyltrimethylsilane ° allyltrimethylsilane: phenylsilane: dienylsilane cotriphenylsilane: dimethylsilane. Trihexylsilane: Tetramexylsilane: Tetraethoxysilane: Methyltrimethoxysilane: Vinyltrimethoxysilane: Vinyltriethoxysilane: Dimethyldimethoxysilane: Hexamethyldisiloxane: Hexamethyldisilazane: Hexamethylcyclotrisiloxane: Hexa Methylcyclotrisilazane: Hexamethyldisilane: Hexamethyldisilthian: Tetrafluorosilane: Tetrachlorosilane: Methyltrichlorosilane; Pinyltrichlorosilane: Allyltrichlorosilane: Phenyltrichlorosilane: Dimethyldidichlorosilane: Dimethyldifluorosilane: Any gas containing volatile silicon-containing compounds such as bromomethyltrimethylsilane may be used. In addition, other compounds may be compounds that are gaseous at room temperature such as ethylene, acetylene, diborane, and phosgene, or so-called monomers such as methyl methacrylate, styrene, acrylonitrile, vinyl chloride, and tetrafluoroethylene. Alternatively, it may be a generally non-polymerizable compound such as benzene ° toluene / xane: acetonitrile: perfluorobenzene: pyridine ° furan: thio-7-encotrimethyl-7-o-7-ite: trimethyl porate.

From an operational point of view as a compound used in plasma polymerization,
Compounds with a boiling point of 20θ℃ or less at room temperature are preferable, and 150
It is more preferable that it is U or less.

Further, as the non-plasma polymerization gas that can be used in the method for producing a magnetic recording medium according to the present invention, oxygen, hydrogen, and nitrogen are preferable, and oxygen and nitrogen are particularly preferred because they react with the plasma polymerization gas to form crosslinking points. This is preferable because it not only incorporates itself into the polymer layer, but also forms a strong bond and improves wear resistance.

In the method for manufacturing a magnetic recording medium according to the present invention, by appropriately adjusting the plasma polymerization conditions, internal stress is generated in the plasma polymerized layer and the magnetic layer is applied to the opposite side of the magnetic layer (i.e., the back side of the support). In other words, the support can be warped. Therefore, when forming a magnetic layer on a support, it is possible to offset the phenomenon in which the support warps against the surface on which the magnetic layer is formed (so-called cupping). When producing a sulfur plasma polymerized membrane that cancels out this cupping, it is desirable to reduce the introduction of a second component gas such as Arbo7 (Ar).

The magnetic material that can be used for the magnetic layer of the magnetic recording medium according to the present invention may be any conventionally used and known magnetic material.
Such magnetic materials include γ-Fe2O3, Co-containing -F
e203, co plated r-Fe203, Fe3O4, CO
Old and old oxide-based magnetic materials containing Fe3O4, CrO2, etc.: Fe-Ni-Co alloy, Fe-Mn-Z11 alloy, Fe-Ni-Zn alloy, p6-C□-Ni-Cr alloy, F'e -Co -Ni--P alloy, Co--Ni alloy, and other alloy-based magnetic materials containing Fe XNi Co as a main component, and other magnetic materials from each village.

Examples of methods for forming the magnetic layer on the support include known vacuum deposition, sputtering, ion blasting, and Mesogi method. When using an alloy-based magnetic material among oxide-based magnetic materials and alloy-based magnetic materials, the composition must be controlled during vapor deposition or plating so that the composition does not change.

The material for the support is polyethylene terephthalate,
Polyesters such as polyethylene-2,6-naphthalate, polyolefins such as polypropylene, cellulose derivatives such as cellulose triacetate and cellulose diacetate, plastics such as polycarbonate, C
Metals such as u, AI, and Zn, glass, and so-called new ceramics (eg, boron nitride, silicon carbide, etc.) are used.

The support may be in any form such as a tape, sheet, card, disk, or drum, and various materials may be selected as necessary depending on the form.

The thickness of these supports is about 3 to 100 .mu.m in the case of a film or sheet, preferably 5 to 50 .mu.m, and about 30 .mu. to 10 .mu.m in the case of a disk or card.

(e) Example: Examples of the present invention will be described below.

Embodiment 1 FIG. 1 shows a sectional view of a main part of a magnetic recording medium manufacturing apparatus according to the present invention.

The manufacturing apparatus consists of a casing indicated by the general reference numeral 1, and the casing 1 has a bell jar-shaped discharge chamber 2, a support delivery chamber (hereinafter simply referred to as the "delivery chamber") 3, and a support winding chamber (hereinafter referred to as "the delivery chamber"). (simply referred to as the "winding chamber") 4, consisting of a discharge chamber 2 and a winding chamber 4: A cylindrical pipe 5 is connected between the discharge chamber 2 and the delivery chamber 3, forming a support passage. .

A conduction pipe 14 is attached to the side walls of the delivery chamber 3 and the winding chamber 4, a branch pipe 15 is connected to the cylindrical pipe 5, and the tip of the conduction pipe 14 is connected to a carrier gas source (not shown). The tip of the branch pipe 15 is connected to an exhaust system (not shown).

Further, if necessary, another branch pipe 15' connected to the exhaust system is provided at the bottom of the winding chamber 4.

Further, the discharge tube 2 is provided with an upper electrode 6 and a lower electrode 7, the inside of the upper electrode 6 is formed into a cavity, one end forms a thin tube, and a non-plasma polymerizable gas source (
Not shown. ), and the other end is provided with a large number of honeycomb-shaped communication holes that communicate with the discharge chamber space, and the structure is such that the non-plasma polymerizable gas introduced into the cavity through the thin tube can be supplied into the discharge chamber. There is. Further, the lower electrode 7 is
A water-cooled groove is provided to cool the heat generated during discharge, and high-frequency power is supplied from a power source 9 via a matching box 8.

When manufacturing a magnetic recording medium using the above-mentioned manufacturing apparatus, first, a support 1o on which a Co-Ni alloy film is deposited on a belt-shaped polyethylene terephthalate film by a known method is wound around a delivery reel 11. , set it in the delivery chamber 3. The tip of the support 1o wound up on the reel 11 is guided inside the cylindrical tube 5 through the guide roller 12,
It is sent from the discharge chamber 2 to the winding chamber 4.

Another take-up reel 13 is installed in the take-up chamber 4, and the reel 11 on the delivery chamber side functions to wind up the support 1o sent into the take-up chamber 4.

In order to overcoat the silicon-containing organic plasma polymerized layer on the Co--Ni alloy film of the support 10 that has been deposited in the casing 1 as described above, first, the entire HF gas system is turned on. After evacuating the inside of the casing 1 through the branch pipe 15, Ar gas is supplied into the casing 1 through the barrel pipe 14.

Next, the upper electrode 6 is grounded, and the lower electrode 7 is connected to the high frequency power source 9 through the matching box 8.
A high frequency power of 6 MHz x 50 W was supplied to generate Ar plasma in the discharge chamber to clean the surface of the Co--Ni alloy film on the support.

Next, vinyltrimethoxysilane is introduced as a silicon-containing compound gas into the cavity through the thin tube part of the upper electrode 6, and oxygen is introduced as a non-plasma polymerizable gas (Φ) in a molar ratio (1:4).
The mixed gas is introduced and the pressure inside the casing 1 is reduced to 0.
11 Torr, and again applied 300W to the lower electrode 7.
high-frequency power is supplied to generate a discharge of Ar gas in the discharge chamber, and the plasma of the vinyltrimethoxysilane gas and oxygen gas supplied to the discharge chamber is applied to the support 10.
The Co-Ni alloy film above was overcoated as a silicon-containing organic plasma polymerized film.

Thereafter, post-processing gas was introduced from the winding chamber 4 side conduction pipe 14, and residual gas inside the casing was removed through the branch pipe 15 of the cylindrical pipe 5.

Furthermore, after returning the inside of the casing 1 to normal pressure, the reel 13 in the winding chamber 4 is removed, and the support 1 wound around the reel is removed.
Talystep the overcoat layer on 0, E S CA
(Electron 5pectroaeopy fo
As a result of analysis by chemical analysis@ig) and elemental analysis, it was confirmed that the film thickness was 280A and the film composition was C0,2zf■o1100.493i0.1g.

In this way, the supported support is 12.65w1ll]
A videotape was made by cutting it into pieces. This sample tape was designated as Example Tape 1.

The manufacturing apparatus shown in FIG. 1 is an example of an apparatus in which a magnetic layer is previously formed on a support 10 outside the apparatus, and then the support is set in a housing fjL and overcoated. However, as shown in FIG. 2, by using a manufacturing apparatus equipped with a vapor deposition chamber 16, which will be described later, in addition to the discharge chamber 2,
The process of forming the magnetic layer on the support and the process of forming the overcoat layer on the magnetic layer can be performed consistently in the same manufacturing apparatus.

In the apparatus shown in FIG. 2, a chamber 17 that serves as both a delivery chamber 3 and a winding chamber 40 is arranged in the center, and a discharge chamber 2 and a vapor deposition chamber 16 are provided on the left and right sides of the chamber 17, separated by partition walls 18, respectively. be.

The vapor deposition chamber 16 is provided with a guide roller 12, a cooling can 20, a melter 21, an electron beam generator 22, and a shielding plate 23.

The strip support 10 fed from the reel 11 passes through a narrow passage 19 provided in the partition wall 18 and is guided to the circumferential side of the cooling can 200 via the guide roll 12.

On the circumferential side of the cooling can 20, the crucible 2 is heated by operating an electron beam generator installed below the cooling can 20.
Co-Ni alloy powder in 1 is heated, and Co is applied to the support 10 surface.
-Ni alloy film is deposited.

The support 1' frame 10 on which the co-Ni alloy film is formed is sent through another guide roller 12, through a slit passage 24, to a release 11 and a manufacturing apparatus shown in FIG. Through the same procedure, a mixed gas (1:4) of vinyltrimethynesilane and oxygen introduced into the upper electrode 6 was added to the C of the support 10.
Plasma polymerization is performed on the o-Ni alloy film, and the magnetic layer of the support and the overcoat layer can be continuously formed in the same apparatus.

Example 2 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film formed on the upper surface of a support 10 in a discharge chamber 2. Instead of glow discharging the mixed gas under the conditions of a gas pressure of 0.1 I Torrs and a high frequency power of 300 W, the following table -
Except for performing a glow discharge using a gas mixture of vinyltrimethoxysilane and oxygen shown in 1 and 2 at a molar ratio (1:2) under the conditions of a gas pressure of 28 Torr and a high-frequency electric crab supplied with a power of 10 W. Co-N on support 10 according to the same treatment and procedure as in Example 1
A silicon-containing organic plasma polymerized layer was formed on the i-alloy film.

After forming the plasma polymerized layer, remove the residual gas in the casing, remove the support 10, and remove the co-N on the support.
When the overcoat layer formed on the i-alloy film was analyzed by Talystep, ESCA, and elemental analysis, the film composition: (::o, tsHo, taQo4sSio,
It was confirmed that it was zt.

The thus obtained support was cut into a length of 12.65 mm to produce a videotape. This sample tape was designated as an example tape.

Below is a margin table-1 Example 3 Using the equipment shown in Figure 1, vinyltrimethoxysilane and oxygen were mixed in molar ratios on a Co-Ni alloy film on a support 10 guided into a discharge chamber 2. (1:4) was mixed with vinyltrimethoxysilane shown in Table 1, N[L3] below to cause a glow discharge at a gas pressure of 0.11 Torr and a high frequency supply of 300W. Nitrogen in molar ratio (1:
Filled gas pressure: 12 t
Co--Ni on the support 10 was prepared in accordance with the same treatment and procedure as in Example 1, except that glow discharge was performed under the conditions of xa Torr supplied high-frequency electric crab 15W.
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 10 from the device, and remove the support 10 from the device.
The overcoat layer on the Co-Ni alloy film above was analyzed by Talystep, E-8CA, and elemental analysis, and the results were as follows: Film thickness: 180 Film composition: C0, 19HO, 12QO, 18N0.2
It was confirmed that it was 2SiO,29.

The support thus obtained was cut to a width of 12.65 m to produce a videotape. This sample tape was designated as Example Tape 3.

Example 4 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film on a support 10 guided in a discharge chamber 2. Instead of glow-discharging the gases mixed in the proportions using a 300W high-frequency electric crab supplied with a sealed gas pressure of + 0.11 Torr, vinyltrimethoxysilane and nitrogen shown in Table 1 below and N114 were mixed in a molar ratio (1:
The gas mixed at the ratio of 1) was filled in at a pressure of 16 W.
Co-Ni on the support 10 was prepared in accordance with the same treatment and procedure as in Example 1, except that glow discharge was performed under the conditions of Torr supply high frequency floating crab 10W.
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 10 from the device, and remove the support 10 from the device.
When the layer overcoated the Co-Ni alloy film above was analyzed by Talystep, ESCA, and elemental analysis, the results were as follows: Film thickness: 160A Film composition: C0, 21H0, 1500, 16N0.19
It was confirmed that it was SiO,29.

The support thus obtained was cut to a width of 12.65 wm to produce a videotape. This sample tape was designated as Example Tape 4.

Example 5 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film on a support 10 guided into a discharge chamber 2. Instead of glow-discharging the gases mixed in the proportions using a high-frequency electric crab supplied with a sealed gas pressure of 0.11 Torr, vinyltrimethoxysilane and hydrogen shown in Table 1 below and Ha 5 were mixed in a molar ratio (2:
1) Filled gas pressure: 155
Co-Ni on the support 10 was prepared in accordance with the same treatment and procedure as in Example 1, except that glow discharge was performed under the conditions of 150 W of high-frequency electric power supplied to the Co-Ni
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 10 from the device, and remove the support 10 from the device.
When the layer overcoated the Co-Ni alloy film above was analyzed by Talystep, ESCA, and elemental analysis, the results were as follows: Film thickness: 22OA Film composition: CO, 231 (0,29Q0.25Si0.
I was able to confirm that it was 23.

The KrJ-coated support was cut to a width of 12.65 mm to produce a videotape. This sample tape was designated as Example Tape 5.

Example 6 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio (1:4 ) Filled gas pressure: 0.11 Torr Instead of glow-discharging using a high-frequency electric crab supplied with 300 W, tetramethylsilane and oxygen shown in Table 1 below and N116 were mixed in the molar ratio (l: 4) The Co-co on the support 10 was subjected to the same treatment and procedure as in Example 1, except that the gas mixed at the ratio of 4) was glow-discharged under the conditions of sealed gas pressure: 15 vx Torr and high-frequency electric crab supplied 15 W. Ni
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 10 from the device, and remove the support 10 from the device.
When the layer overcoated the Co-Ni alloy film above was analyzed by Talysteds ESCA and elemental analysis, the following results were obtained: Film thickness: 160A Film composition: 2co1s1(o, osQo, 5zSio, z2
It was confirmed that this was the case.

The thus obtained support was cut to a width of 12.65 m to produce a videotape. This sample tape was designated as Example Tape '6.

Example 7 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film on a support 10 guided in a discharge chamber 2. Filled gas pressure: 0.11 Torr Instead of glow-discharging gases mixed at the same ratio using a high-frequency electric crab supplied with gas, the molar ratio of tetramethylsilane and oxygen shown in Table 1 below (N[L7) (1: Co-Ni on the support 10 was produced in accordance with the same treatment and procedure as in Example 1, except that the gas mixed at the ratio of 5) was glow-discharged under the conditions of a sealed gas pressure of 140 saTorr and a supplied high-frequency electric crab of 300 W.
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 10 from the device, and remove the support 10 from the device.
When the layer overcoated the Co-Ni alloy film above was analyzed by Talystep, ESCA, and elemental analysis, the results were as follows: Film thickness: 180A Film composition: Co2t, lo, osQo, 4tSio, s
It was confirmed that s.

The support thus obtained was cut to a width of 12.65 m to produce a videotape. This sample tape was designated as Example Tape 7.

Example 8 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film on a support lo guided in a discharge chamber z. Instead of glow-discharging the gases mixed in the proportions using a 300W high-frequency electric crab supplied with a sealed gas pressure of 0.11 Torr, the molar ratio of hexamethyldisilazane and nitrogen shown in Tables 1 and 8 below (1: 5) Co on the support l was carried out according to the same treatment and procedure as in Example 1, except that the gas mixed at the ratio of -Ni
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 1o from the device, and remove the support 1o from the device.
When the overcoat layer on the Co-Ni alloy film above was analyzed by Talystep, ESCA, and elemental analysis, the film thickness was 24OA. Film composition: C0, 12H0, 1400, 02N0.36.
It was confirmed that 8i o, ae.

A videotape was prepared by cutting the support thus obtained into a width of 12.65 mm. This sample tape was designated as Example Tape 8.

Example 9 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film on a support 10 guided into a discharge chamber 2. Instead of glow-discharging the gases mixed at the same ratio using a 300W high-frequency electric crab supplied with a sealed gas pressure of 0.11 Torr, hexamethyldisilazane and oxygen shown in Table 1 below and N[L9 were mixed at a molar ratio of (1 :3
Co-coated on the support io according to the same treatment and procedure as in Example 1, except that the mixed gas at the ratio of Ni
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 1o from the device, and remove the support 1o from the device.
When the layer overcoated the Co-Ni alloy film above was analyzed by Talystep, ESCA, and elemental analysis, it was found that: Film thickness: 260A Film composition: Co1x)io, t4Qo, z2No, zs
It was confirmed that it was Sio, zs.

The thus obtained support was cut into 12.65 mm pieces to produce a videotape. This sample tape was designated as Example Tape 9.

Example 10 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film on a support 10 guided in a discharge chamber 2. To generate a glow discharge using a 300W high-frequency electric crab supplied with a gas pressure of 0.11 Torr, hexamethyldisilazane and oxygen shown in Table 1 below and Na1O were mixed at a molar ratio of 1: 1
) on the support 10 according to the same treatment and procedure as in Example 1, except that the gas mixed at the ratio of Co-Ni
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 10 from the device, and remove the support 10 from the device.
When the layer overcoated the Co-Ni alloy film above was analyzed by Talystezzo, ESCA, and elemental analysis, it was found that: Film thickness: 26OA Film composition: Co, o9HolaQo, z4No, zaS
It was confirmed that it was io2s.

The thus obtained support was cut into 12.65 mm pieces to produce a videotape. This sample tape was designated as Example Tape 10.

Example 11 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1:4) on a Co-Ni alloy film on a support 10 guided in a discharge chamber 2. In order to cause the gases mixed in the proportions to glow discharge using a high-frequency electric crab supplied with a sealed gas pressure of 0.11 Torr, hexamethyldisiloxane, thiophene, and oxygen shown in Table 1 below, Nα11, were mixed in molar ratios ( The support 10 was prepared in accordance with the same treatment and procedure as in Example 1, except that a gas mixed in a ratio of 20/1/10) was glow-discharged under the following conditions: Filled gas pressure: 5 Torr High frequency power supplied: 50 W Co-Ni above
A plasma polymerized film was formed on the alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support 10 from the device, and remove the support 10 from the device.
When the layer overcoated the Co-Ni alloy film above was analyzed by Talystep, ESCA, and elemental analysis, the results were as follows: Film thickness: 240A Film composition: Co, t*Ho, z4Qo2tSio, ts
It was confirmed that it was 3o, tt.

The support thus obtained was cut to a width of 12.65 m to produce a videotape. This sample tape was designated as Example Tape 11.

Example 12 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed at a molar ratio of (1/4) on the Co-Ni alloy film of the support 10 guided in the discharge chamber 2. Hexamethyldisiloxane, trimethylphosphite, and oxygen shown in Table 1 and Section 12 below were used instead of glow-discharging the gases mixed in the proportions at 300W to an eight-frequency wave supplied with a sealed gas pressure of 0.11 Torr. The same treatment and procedure as in Example 1 was followed except that gases mixed at a molar ratio of (20/1/10) were glow discharged under the reaction conditions of a sealed gas pressure of 10 mya Torr and a high frequency electric crab supplied with 80 W. , Co-N on support 10
A plasma polymerized film was formed on the i-alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, remove the support lO from the apparatus, and remove the support lO from the apparatus.
The overcoat layer formed on the upper Co-Ni alloy film,
Analyzed by crystal tube, ESCA and elemental analysis, film thickness: 280A film composition: C0,1ei(o,t9Q0.28Si
It was confirmed that it was O,24p0.13.

The thus obtained support was cut to a width of 12.65 ax to produce a videotape.

This sample tape was designated as Example Tape 12.

Example 13 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1/4) on the Co-Ni alloy film of the support 10 guided into the discharge chamber 2. Instead of glow-discharging the mixed gas using a 300W high-frequency electric crab supplied with a sealed gas pressure of 0.11 Torr, phenylsilane, benzene, and oxygen shown in Table 1 below, Nα13, were mixed in the molar ratio (
Filled gas pressure: 4/1/4)
The Co-N on the support 10 was prepared by following the same treatment and procedure as in Example 1, except for glow discharge under the reaction conditions of 205 m1 Torr and high frequency electric crab supplied at 300 V,'.
A plasma polymerized film was formed on the i alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 10 from the apparatus, and remove the support 10 from the apparatus.
An overcoat layer formed on the upper Co-Ni alloy film,
When analyzed by crystal tube, ESCA, and elemental analysis, film thickness: 180A film composition: C0.25L (o, o 8Q0.21S
I confirmed that it was O,43.

The support thus obtained was cut to a width of 12.65 mm to produce a videotape.

This sample tape was designated as Example Tape 13.

Example 14 Using the injection molding apparatus shown in FIG. (1/4
) in the molar ratio of phenylsilane, methyl methacrylate and nitrogen ( The same treatment and procedure as in Example 1 was followed except that the gases mixed in the ratio of 5/3/40) were glow-discharged under the reaction conditions of sealed gas pressure: 135 mm Torr and high-frequency electric power supply.

A plasma polymerized film was formed on the upper Co-Ni alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 1o from the apparatus, and
The overcoat layer formed on the upper Co-Ni alloy film,
When analyzed by crystal tube, ESCA, and elemental analysis, film thickness: 160A Film composition: C0, 27H0, 2800, 19N0.10
It was confirmed that S i O,16.

The support thus obtained was cut to a width of 12.65 ym to produce a videotape.

This sample tape was designated as Example Tape 14.

Example 15 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed at a molar ratio of (1/4) on the Co-Ni alloy film of the support 1o guided into the discharge chamber 2. Hexamethylcyclotrisiloxane, trimethylporate, and oxygen shown in Table 1 below, Na15, were mixed in a molar ratio of hexamethylcyclotrisiloxane, trimethylporate, and oxygen as shown in Table 1 below to generate a glow discharge using a high-frequency electric crab supplied with a sealed gas pressure of 0.11 Torr. The same treatment and procedure as in Example 1 was carried out, except that gases mixed in a ratio of (10/1/20) were glow-discharged under the reaction conditions of sealed gas pressure: 135 m Torr and high-frequency electric crab supplied at 180 W. Co-N on body 10
A plasma polymerized film was formed on the i-alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 10 from the apparatus, and remove the support 10 from the apparatus.
The overcoat layer formed on the upper Co-Ni alloy film,
When analyzed by Talystep, ESCA and elemental analysis, film thickness: 260A film composition: C0,21J (0,14Q0.43SiO
,11130,11.

The support thus obtained was cut into a width of 12.65 mm to produce a videotape.

This sample tape was designated as Example Tape 15.

Example 16 Using the manufacturing apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed at a molar ratio of (1/4) on the Co-Ni alloy film of the support 10 guided in the discharge chamber 2. Instead of glow-discharging the gas mixed in the proportions with a high-frequency electric crab supplied with a 300W high-frequency electric crab at a sealed gas pressure of 0.11 Torr, hexamethylcyclotrisiloxane, vinyl chloride, and hydrogen shown in Table 1 below, N16, were mixed in the molar ratios. The same treatment and procedure as in Example 1 was followed, except that a gas mixed in a ratio of (515/2) was glow-discharged under the reaction conditions of a gas pressure of 11 vm Torr and a high-frequency electric crab supplied with 8 W.

A plasma polymerized film was formed on the upper Co-Ni alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 10 from the apparatus, and remove the support 10 from the apparatus.
The overcoat layer formed on the upper Co-Ni alloy film,
When analyzed by Talystep, ESCA and elemental analysis, film thickness: 260A film composition: Co, a3 (o, osQo, xsSio,
It was confirmed that as(Jo, o:+).

The support thus obtained was cut to a width of 12.65 m to produce a videotape.

This sample tape was designated as Example Tape 16.

Comparative Example 1 Using the apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1/4) on the Co-Ni alloy film of the support 10 guided into the discharge chamber 2. In order to cause the mixed gas to glow discharge under the conditions of sealed gas pressure: 0.11 Torr and high frequency electric crab supplied 300W, the following Table-2, FJ[
The same treatment and procedure as in Example 1 was followed except that the vinyltrimethoxysilane shown in L 1 was glow discharged under the reaction conditions of a filled gas pressure: 1 8 yen Torr supplied high frequency electric crab 50 W, to prepare support 1.

A plasma polymerized film was overcoated on the upper Co--Ni alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 1o from the apparatus, and
The overcoat layer formed on the upper Co-Ni alloy film,
When analyzed by Talystep, ES CA, and photogravimetric analysis, film thickness: 260A Film composition: ('0.31) (0,13si0.33Q0
．． I confirmed that it was 23.

The support obtained in this way was cut into 12.65 mm width to make a videotape! I did it.

This sample tape was designated as Comparative Example Tape 1.

Margin Table 2 Comparative Example 2 Using the apparatus shown in Figure 1, vinyl trimethoxysilane and oxygen were mixed in a molar ratio (1/4 ), vinyltrimethoxysilane and ethylene shown in Table 2, h2 below were added in molar ratios to generate a glow discharge under the conditions of sealed gas pressure: 0.11 Torr and high frequency electric power supply. The gases mixed at a ratio of (1/1) were placed on the support 10 according to the same process and procedure as in the example process, except for glow discharge under the reaction conditions of a sealed gas pressure: 35 ws Torr and a high frequency electric crab supplied at 100 W. Co-N
A plasma polymerized film was overcoated on the i-alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 10 from the apparatus, and remove the support 10 from the apparatus.
The overcoat layer formed on the upper Co-Ni alloy film,
Film thickness: 220A Film composition: Co4n)io, xsSio, zsQo, x
It was confirmed that s.

The support thus obtained was cut to a width of 12.65 m to produce a videotape.

This sample tape was designated as Comparative Example Tape 2.

Comparative Example 3 Using the apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1/4) on the co-Ni alloy film of the support 10 guided into the discharge chamber 2. Instead of glow discharging the mixed gas under the conditions of sealed gas pressure: 0.11 Torr and high frequency electric crab supplied 300W, the following Table-2, Nα3
Co-N on a support weight of 0 was carried out according to the same treatment and procedure as in Example 1, except that the tetramethylsilane shown in was glow-discharged under the reaction conditions of 12 tm'fOrr supplied high-frequency electric crab 100W.
A plasma polymerized film was overcoated on the i-alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 10 from the apparatus, and remove the support 10 from the apparatus.
The overcoat lip formed on the upper Co-Ni alloy film,'
When analyzed by Christetsub, ESCA and elemental analysis, film thickness: 180A film composition; (::o51Ho, o4Sio, +oQo,
I confirmed that it was OS.

The support thus obtained was cut to a width of 12.65 mm to produce a videotape.

This sample tape was designated as Comparative Example Tape 3.

Comparative Example 4 Using the apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1/4) on the Co-Ni alloy film of the support 10 guided into the discharge chamber 2. Instead of glow-discharging the mixed gas under the conditions of sealed gas pressure: 0.11 Torr and supply high frequency type crab 300W, the following table-2, N[L
A gas mixture of tetramethylsilane and styrene shown in 4 at a molar ratio (1/1) was charged at a pressure of:
The same treatment and procedure as in Example 1 was followed except for glow discharge under the reaction conditions of 125 wm Torr and high frequency electric crab supplied with 300 W of Co-N on the support 10.
A plasma polymerized film was overcoated on the i-alloy film.

After forming the 7' plasma polymerized film, remove the residual gas in the casing, take out the support 10 from the device, and remove the support 10 from the device.
The overcoat layer formed on the Co-Ni alloy film on 0 was analyzed by Talystep, ESCA, and elemental analysis, and the results were as follows: Film thickness: 300A Film composition: (:o, 5sHo21Sio, +tQo, o
It was confirmed that s.

The support thus obtained was cut into 12.65 m pieces to produce a videotape.

This sample tape was designated as Comparative Example Tape 4.

Comparison row 5 Using the apparatus shown in FIG. 1, vinyltrimethoxysilane and oxygen were mixed in a molar ratio of (1/4) on the Co-Ni alloy film of the support 10 guided into the discharge chamber 2. Instead of glow discharging the mixed gas under the conditions of sealed gas pressure: 0.11 Torr and high frequency electric crab supplied 300W, the following Table-2, F1α
Hexamethylcyclotrisilazane shown in No. 5 was charged using a high-frequency electric crab 250 gas pressure: 140 mm Torr supply.
Co--N on the support 10 was prepared by following the same treatment and procedure as in Example 1, except for glow discharge under the reaction conditions of W.
A plasma polymerized film was overcordoned onto the i-alloy film.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 10 from the apparatus, and remove the support 10 from the apparatus.
The coating layer formed on the upper Co-Ni alloy film is
Roller A analyzed by Talystep, ESCA and elemental analysis, film thickness: 360A, film composition: C0,31HO,1tsio, 3300.
It was confirmed that it was 08N0.17.

The support thus obtained was cut to a width of 12.65 wra to produce a videotape.

This sample tape was designated as Comparative Example Tape 5.

Comparative Example 6 Using the apparatus shown in Figure 1, vinyltrimethoxysilane and oxygen were mixed at a molar ratio of (1/4) on the Co-Ni alloy film of the support 1o guided into the discharge chamber 2. Instead of glow-discharging the gas under the conditions of sealed gas pressure: 0.11 Torr and high-frequency electric crab supplied 300W,
Example 1 except that the hexamethylcyclotrisilazane shown in 6 was glow-discharged under the reaction conditions of sealed gas pressure = 18 Torr and high frequency type crab supplied 30W.
According to the process and hand JIUi, the support 1
A 7° lasma polymerized film was overcoated on the co-Ni alloy film on the 7°.

After forming the plasma polymerized film, remove the residual gas in the casing, take out the support 1o from the device, and remove the support 1o from the device.
The overcoat layer formed on the upper Co-Ni alloy film,
When analyzed by Talystep, ESCA and elemental analysis, film thickness: 320A film composition: (:o, zsHo, otsio2aQo,
It was confirmed that it was tolyJo and az.

The support thus obtained was cut into pieces of 12.65 m to produce deo tape.

This sample tape was designated as Comparative Example Tape 6.

Next, we will discuss the refractive index, dynamic friction coefficient, as) deterioration, and tape still life of the overcoat layer of each Example Tape 16 and Comparative Example Tape 6 obtained in Examples 1 to 16 and Comparative Examples 1 to 6. The measured results are shown in the table below.
Shown in 3.

Margin Table 3 Below: Coefficient, AS deterioration rate, and stell life were evaluated according to the following methods.

(a) Refractive index of overcoat layer: Determined using an ellipsometer.

(b) Coefficient of dynamic friction of overcoat layer: Warm up the tape! 2
After leaving the tape in an atmosphere of 5°C and 55% relative humidity for 24 hours, one end of the tape was attached to the tension detection part, and the other end was set to 30? A load is applied and the tape is held stationary, and a rotating roller (diameter 4 gates) is brought into contact with the bottom surface of the tape to increase the circumferential speed to 1.
When rotated at 4 mx/sec, the value detected by the tension detection section was defined as the dynamic friction coefficient.

(c)'s deterioration rate: The tape was exposed to high temperature and humidity conditions (temperature 60℃, relative humidity 80℃).
From the saturation magnetization 0s of the tape after being left for one week at φ) and the saturation magnetization 'so of the tape before being left, it is determined according to the following formula: σS inferiority ratio=(C-U-) x io.

0 It was displayed with.

(d) Still life: The time it takes for a reproduced still image on the TV screen to disappear (6
) expressed in units. In addition, the film thickness of the overcoat layer of the tape in Examples 1 to 16 and Comparative Examples 1 to 6 was R
The measurement was carried out according to a conventional method using a crystal tube manufactured by ANK TALOV LLOBSON.

From the measurement results shown in Table 3, the sample tape whose overcoat layer has a refractive index of 1.45 or less (Comparative Example Tape 6)
Compared to the sample tape with a refractive index of 1.45 or higher (Example Tape 16), both the coefficient of dynamic friction and the AS deterioration rate were larger, the tape had poor runnability and was prone to scratches, and had poor corrosion resistance (storage stability). It turns out to be inferior.

Furthermore, it can be seen that sample tapes with an overcoat layer having a refractive index of 1.45 or more have a longer still life and excellent abrasion resistance than sample tapes having an overcoat layer with a refractive index of 1.45 or less.

When the relationship between the refractive index of the sample tape and the still life is plotted based on the measured values shown in Table 3, the results are shown in FIG. 3. In the figure, the X mark is the characteristic value of the sample tape with a refractive index of 1.45 or less, and the * mark is the refractive index of 1.45 or less.
The characteristic values of the above sample tapes are shown below. When interpolation lines are plotted based on this result, two types of interpolation lines C1 and 02 are obtained.

From the interpolated lines C and C2, the still life of the tape having an overcoat layer with a refractive index of 1.45 or more is 1.4.
This has significantly increased the still life of tapes with an overcoat layer of 5 or less, and the abrasion resistance of the tape has improved.
It turns out that I did it.

(f) Effects of the invention: As described above, according to the present invention, the magnetic recording medium has: (1) improved running performance, and fewer disturbances in the screen or recording due to poor running;

■ Also, because it has high wear resistance, there is little fluctuation in the output signal even when used for long periods of time.

■ Furthermore, because it has excellent corrosion resistance, there is little deterioration in the playback output even if it is left under high temperature and high humidity conditions for a long time.
High storage stability can be obtained.

[Brief explanation of drawings]

Figure KrJ1 is a sectional view of the main part of the magnetic recording medium manufacturing apparatus of the present invention, and Figure 2 is the magnetic recording medium manufacturing apparatus of the present invention! FIG. 3 is a sectional view of a main part of another embodiment of the present invention, and FIG. 3 shows the relationship between the refractive index of the overcoat layer and the still life of a magnetic recording medium according to the present invention and a magnetic recording medium of a comparative example. It is a curve diagram. 2...Discharge chamber, 3...Support delivery chamber 4...Support winding chamber, 6...Upper electrode, 7...・Lower 15 poles, 8...Matching box 9...High frequency electric ridge 10...
...Support, 11...Support delivery reel, 13...Support take-up reel Patent applicant Konishiroku Photo Industry Co., Ltd. Written amendment to the commission procedure (voluntary) September 14, 1981 1, Indication of the case 1988 Special J't 1 No. 1.45], No. 93-2, Name of the invention Magnetic recording medium and its manufacturing method 3 , Relationship with the Case of Person Who Corrects H Patent Applicant Address 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name
(127) Konishiroku Photo Industry Co., Ltd. 6. Contents of the amendment as shown in the attached sheet. [1] @Claim range value amended as shown on the attached sheet. [2] Paulownia in the detailed description of the invention is amended as follows. (1) In the first line of page 2 of the specification, the statement "...relating to a thin film magnetic recording medium" is changed to "...relating to a thin film magnetic recording medium and its manufacturing method." (2) The descriptions 1...W, J on page 3, line 8 of the specification should be changed to "...WCl". (3) The statement "...abrasion resistance..." in the third line of page 6 of the specification is changed to "...abrasion resistance...". (4) From the first line from the bottom of page 6 to the second line of page 7 of the specification, the overcoat layer must be composed of a silicon-containing organic plasma polymerized layer with a refractive index of 1.45 or more. ...”
There is a description that ``...the overcoat layer has a refractive index of 1.4.
5 or more, and be made of a silicon-containing organic plasma polymerized layer. (5) Page 9 of the specification, lines 1 to 3 [...The refractive index is 1.
Overcoating with a silicon-containing organic plasma polymerized layer of 45 or more...'' was changed to ``...forming an overcoat layer composed of a silicon-containing organic plasma polymerized layer with a refractive index of 1.45 or more. I decided to. (G+ Specification page 9, lines 1 to 3, [...tetramexylsilane/...] is changed to "...tetramethoxysilane...". (7) RejI! fi1!1. Delete the statement "...among oxide-based magnetic materials and alloy-based magnetic materials..." on page 12, lines 13-14. (8) Specification, page 53, 6 Row ``...Ran1c t
alov) io b son-J
・JRank talorno bson・-J
shall be. Above (Attachment) Claims (1) A magnetic recording medium having a magnetic Hη and an overcoat layer formed on the magnetic layer on a support, wherein the overcoat layer has a refractive index of 1.45 or more and contains It is made up of organic plasma polymerized layer. A magnetic recording medium characterized by its green color. (2) After forming a magnetic layer on the support, a non-plasma submerged gas and a silicon-containing compound are treated with plasma 11ξ at the same R,'f on the magnetic layer, and once on the magnetic layer, A method of manufacturing a magnetic recording medium. Procedural amendment 5B, 12.17 Showa year, month, day 1 Indication of the case 1988 Relationship with Patent Application No. 145193, 41 cases Patent cord 1 person Address 1-26 Nishi-Shinjuku, Shinjuku-ku, Tokyo, No. 2 Trap l″′
1, O;) (127) Konishi Rokushayo 1. Kariguchi, Shikisha Representative Director Nobuhiko Kawamoto 7, Subject of amendment (1) Application based on ``Patent Act No. 36'' to ``Patent Act No. 38''
amend the patent application pursuant to the provisions of ``Proviso''. (2. Number of inventions stated in the scope of claims) shall be amended to 2.

Claims (2)

[Claims] (1) In a magnetic recording medium having a magnetic layer and an overcoat layer formed on the magnetic layer on a support, the overcoat layer is composed of a silicon-containing organic plasma polymerized layer having a refractive index of 1.45 or more. A magnetic recording medium with a % characteristic of (2) After forming a magnetic layer on the support, a non-plasma polymerizable gas and a silicon-containing compound are simultaneously subjected to plasma polymerization treatment on the magnetic layer, and a silicon-containing compound having a refractive index of 1.45 or more is coated on the magnetic layer. Magnetic recording medium 0 having a magnetic layer and a silicon-containing organic plasma polymerized layer with a refractive index of 1.45 or more formed on the magnetic layer on a support characterized by overcoating a silicon organic plasma polymerized layer.