JPS59165234A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve corrosion resistance and running stability and to minimize spacing loss by sticking at least one among phosphate, phosphite and trialkyl phosphine oxide on a thin ferromagnetic metallic film. CONSTITUTION:A thin ferromagnetic film of single or multiple layers consisting essentially of Co, Fe, Fe-Ni, Co-Ni, etc. of 0.05-0.5mum thickness composed of a diagonal or perpendicular columnar crystal and contg. 3-45% oxygen by an atom ratio to an acidic metal is formed on a nonmagnetic substrate by a method such as vapor deposition or sputtering in a vacuum where a very small amt. of gaseous oxygen exists. At least one of phosphate, phosphite and trialkyl phosphine oxide is stuck on the thin film. These compds. provide the effect when they are formed to exist on the surface of the thin ferromagnetic film. The preferred material thereof is a compd. having >=8 length of carbon chain and the adequate amt. thereof is about 0.5-500mg for each 1m<3> of a magnetic recording medium. The practical method of forming said material to exist on the surface of said film includes a method of diluting the compds. in a solvent and coating the soln. on the surface and a method for applying the vapor thereof on the surface of the thin film.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic recording medium of the 11q type, which is particularly excellent in high-density recording, among magnetic recording media.

Conventional configurations and their problems Magnetic recording media have recently become more advanced with the spread of video systems, audio systems, computer systems, etc., and their main component is ferromagnetic iron oxide. There has been a shift from traditional media to media based mainly on metals and metal vapors. In particular, magnetic recording media produced by the metal vapor deposition method are produced by vapor deposition in vacuum on the surface of a substrate made of a non-magnetic material such as a plastic film such as polyester film or polyimide, an aluminum film, or a ceramic plate. By ion blating, sputtering, etc. jl) Fe-Ni
, Co, Cr, or an alloy thereof, and contains oxygen, ferromagnetic thin +1+>% *formed,
It is suitable for high-density recording such as video signal recording. But bullets? i, <', the thickness of the metal thin film is 0.05
11% due to its small size of ~0.5 μm? "Early J'5'
During i, the temperature change is particularly large. Lifting platforms that have been left in an environment where corrosion is likely to occur are susceptible to corrosion on the surface, and if this corrosion progresses to a certain extent, corrosion will occur on the surface.
It affects the shielding characteristics and deteriorates practical characteristics such as head touch and abrasion resistance. In addition, these magnetic recording media t
During recording and playback, the magnetic head and rh>L<
Since the rq and rq are in contact with each other, abrasion is severe, and a material with excellent abrasion resistance is desired.

Therefore, 't' like Rex, paraffin, etc. can be deposited on the magnetic film.
It has already been proposed to provide a protective layer such as 1117j made of lubricant or the like. However, although this method can temporarily achieve all objectives, this "1 protective film has a weak risk of tightness with the amphoteric layer, so it easily rubs against the air head." If these anti-rust agents and lubricants are formed separately, the spacing loss between the head and the lubricant layer will increase. If you try to do so, you may lose these benefits, or you may even end up accelerating corrosion.

7 Yota, JP-A-50-66206 and JP-A-66207 both disclose a protective layer containing higher aliphatic alcohol-μ phosphoric acid varnish 7-/silica nitrocellulose or polyvinyl μ-glyral resin on a magnetic film. A magnetic recording medium provided with a film is disclosed in Japanese Patent Application Laid-Open No. 15803/1983 using Monolin! A magnetic medium with excellent dispersibility, storage stability, and quality reproduction output of magnetic powder using bisphosphoric acid ester was disclosed in Japanese Patent Application Laid-Open No. 55
-111105 publication discloses mono-dihydrophosphoric acid ester μ,
With screws (Magnetic aggregates with improved coercive force reduction by welding phosphoric acid esthetic μ and iron materials have been shown, but the magnetic recording media used in these are magnetic.) The recording medium is a coated inkstone recording medium consisting of a binder and a magnetic powder, and the magnetic 1yl used in the above medium is F.
e2O3, Co-containing Fe103, Fe 304゜Co
Contains Fe50. , CrO2, etc., which are already oxides and are relatively stable. The magnetic recording medium in the application area is composed of a bond j'+lI and a magnetic powder, which generally contains an antistatic agent, a stabilizing AIJ, and the like. However, the benefits cannot be obtained unless the ferromagnetic metal layer, the magnetic medium 2, the binder, and the lubricant 1j are activated on the surface layer. Spacing loss with the head is a major problem, and since it is a fully refracted thin film, corrosion resistance becomes a problem, making the above-mentioned direct application impossible.

OBJECTS OF THE INVENTION An object of the present invention is to provide a magnetic recording medium that has high corrosion resistance, excellent running stability, lubricity and durability, and does not suffer from large spacing loss.

Structure of the Invention The magnetic recording medium of the present invention comprises oxygen-containing ferromagnetic gold 1. formed on a non-magnetic substrate. At least one of 411 phosphorus esters, saliva phosphorus esters, and trialkyl rephosphine oxides is applied to the rishi thin jhan, and some of these are reacted with metals to create a strong foundation. It is characterized by being anti-Q and a lubricant.

Non-magnetic large plate (7) includes polyester I film, polyimide film, sun plastic film, 7/
Metal plates such as reminium plates and Suanres plates, and f′ nail plates such as -hiramic plates are used, on which a trace amount of oxygen gas is present either directly or through non-magnetic J or W. Diagonal or vertical columnar shape using methods such as steaming in a vacuum, snow (tsutaring), and ionpu 1/-tifugu!
Fr: Co with a thickness of 0.05 to 05 μm, consisting of
Fe, Fe-Ni, Co-Ni, Co-Cr,
Mainly composed of Fe-Co, Fe-Co-Ni, etc. (('9
”=J f l1ii gold L/bow atomic ratio of 3 to 4
A single layer containing 5% S or a ferromagnetic layer containing 1% S was formed.

The phosphoric acid ester, the phosphorous ester, and the trialkyμphosphine oxide are represented by the following chemical formula.

(1) Phosphate Estheticumu (R,O) (R201(R30)PO(2) Asunshun Estheticumu (R10) (R20') (R30) P(3)
) Ria Irephosphine Ogicide ■ 3PO In the formula, R1, R, , R3 are each independently hydrogen, an alkyl μ group, an ali Iv group, a phenyl macrophenyl group, and an alkylphenyl group to 7'r, υ and R are compounds consisting of alkyl groups, and a mixture of these may be used. That is, the above (1
) are trial, dial, and mono al.
Phosphoric acid ester μ such as Rekyl is converted into Kaneko E:h, (2) (r, trialkyl, sialyl, monoalkyl/
L' (1) +lij riff i-beak 1 stell included. These compounds exhibit their effects by being present on the surface of the bow ii26R characteristic lv piece. 9α5-50 per 17ng of air recording medium in a bucket
It is about 0 mg. As for how to make it exist concretely,
A method of diluting these phosphorus compounds with a solvent and applying them, a method of applying vapor to the surface of a ferromagnetic thin film, and a method of applying the phosphorus compound to the surface of a ferromagnetic thin film.
173 Z) If it is in the form of a tape, known means can be used, such as a method in which it is made to exist on the back surface and is transferred to the surface of the ferromagnetic thin film when the tape is rolled up.

Ability: Explanation of one example Next, specifically the W! of the present invention! ); Explaining the u example 4
A polyester plastic film with a thickness of 10 μm was placed along the circumferential surface of a cylindrical can, and a CoNi alloy (CoNi alloy) melted by electron beam heating was introduced into a vacuum of 5×10 Torr at a rate of α3t/min. Ni content] amount 2
0 wt %) was continuously obliquely deposited (cutting the low incident angle component below 30°), and a thin 100 OA thick CoNi ferromagnetic film with an oxygen core was formed on the film. As a result of measuring the amount of oxygen in the film mainly using Auger'i and molecular spectroscopy, it was found that the average oxygen 1tk in the film of sample A was 10% in atomic ratio (once = 00) to Co and Ni. . Apply phosphoric acid to the surface of this sample A, apply phosphoric acid, and trialkylphosphine oxide to the cheek.
Ketones, aromatic fumes (dissolved in hydrocarbons, etc.)
After adjusting the temperature to 90% R at 50°C,
Released into H atmosphere +7. +7, during which time the state of rust on the surface was examined by periodically taking it out and inspecting it under a microscope. The results are shown in Table 1.

In addition, the tape applied under Lee conditions was tested at 30°C90'11
Changes in the braking force were measured repeatedly when running on the stainless steel boss 1 in an environment of 0RH, and the results are shown in Table 2.

In fact, in Sunsample Nn3-13, ferromagnetic gold 1. i;
Tapes coated with thin 1IIi% phosphorus ester and phosphorous acid ester and trialkylphosphine oxide were either uncoated [actual strength example slow 1] or rough-in coating [dormitory; example]. 2) Compared to tape, it has significantly improved corrosion resistance and can be used under high humidity 'E+# conditions (30℃, 90%
It is clear that the changes in the island/friction during green return driving in R)I) are small, that is, the stability of the driving is achieved.

-Also, like Experiment Example 14, Rin 1 Shun Nistelt 11+
Even if I applied phosphoric acid ester/l', there was no actual smell Nu 1,
Superior results were obtained compared to rh 2, and in the present invention ld
Phosphite Esthe I and Phosphite Esthe μ,) Add at least one of the following: The hometown is 〒i).

In addition, in the above example '1, iJ: Co containing oxygen.
-N i book membrane 1 t! GL! However, the present invention (
Similar effects can be obtained with 1.I.times.1j.4 such as rl, Co, Fe-Ni, Fe-Co, and Co-Cr.

According to the detailed description of the invention, the recording medium of the present invention has a strength of 1.
Phosphorus i' in the 1α gold dust thin film? 9 ester, phosphite ester, +: H) At least one of Rialky I refosbuin oxide is attached, so it has high corrosion resistance and properties, as well as running stability (lubricity and ease of use). This provides a magnetic recording medium that is excellent in performance and does not suffer from large spacing loss.

Agent: Written by Yoshihiro Moto

Claims (1)

[Claims] 1. A magnetic recording medium in which at least one of a phosphate ester, a phosphite, and a trialkylphosphine oxide is attached to a ferromagnetic metal film containing oxygen formed on a nonmagnetic substrate.