JPS58175133A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To provide high wear resistance and shelf stability and to obtain high reproduction output, by adding a specified compound to a magnetic recording layer. CONSTITUTION:To a magnetic recording layer on the surface of a support is added a compound represented by formula I or II, wherein R is optionally substituted alkyl, alkenyl, aryl or acyl, Z is -O-, -S- or -NH-, M is a alkali metallic salt or an ammonium salt, and n is an integer of 1-5. The compound is concretely represented by formula III or IV.

Description

[Detailed Description of the Invention] This invention relates to magnetic recording media such as magnetic tapes and magnetic tapes, and in particular to high-density magnetic recording media that have good wear resistance, storage stability, and high playback output. It is.

Conventionally, in magnetic recording media such as recording tapes and video chips, magnetic fine powder such as Fe30q%Fe-Co-Ni alloy is mixed with vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyritine chloride copolymer, polyacrylic acid. Butyl, butyl acrylate-acrylonitrile copolymer, cellulose resin, epoxy resin, polyurethane resin are dispersed and kneaded in a binder to form a coating solution, polyethylene terephthalate, cellulose triacetate, and a binder. bonato,
It is important to install a VCC film on the surface of an L-shaped non-magnetic support such as polypropylene or polyvinyl chloride. Even if these binders are used alone or in combination, the wettability between the particle surface of the magnetic fine powder and the binding network is insufficient, and the shape of the magnetic fine powder particles has acicular crystals. The dispersibility of magnetic fine powder in a binder tends to be poor due to reasons such as The properties that should be provided, such as abrasion resistance and storage stability, were not fully satisfied.

In particular, in video tapes that require short wavelength recording, poor dispersion of magnetic powder in the magnetic layer causes deterioration of the S/N ratio and decrease in sensitivity. Due to repeated use, the magnetic coating is worn out and the magnetic powder contained in the core coating tends to fall off, giving rise to undesirable results such as clogging of the magnetic head.

For this reason, various additives are used for the purpose of completely controlling the particle size distribution of the magnetic fine powder, improving the dispersibility of the magnetic fine powder in the binder, and improving the wear resistance. For example, Special Publications No. 41-18064, No. 43-186, No. 43
No.-669, No. 47-15624, JP-A-4G-53
No. 402, No. 49-58804, No. 49-84405
No. 51-40904 and No. 52-70811, higher fatty acids, fatty acid amides, fatty acid esters, and higher alcohols are added to the magnetic powder fraction paint containing magnetic powder and binder. , metal soap, sulfuric acid ester of higher alcohol, polyenalene oxide, and lentin group, and this magnetic powder I & paint is placed on the surface of a non-magnetic support to produce a magnetic recording medium. There is.

However, even with the addition of these additives, the same magnetic properties as above,
In terms of wear resistance and long-term storage stability, it has been difficult to form a magnetic recording layer that has desirable properties. That is, for example, if a large amount of these additives 41 is used, the mechanical strength of the second recording layer will be reduced, which is an undesirable result. In addition, after the formation of the magnetic recording layer, changes over time were observed, and the gradual addition to the surface of the magnetic recording layer
A so-called blooming phenomenon occurs, and tackiness is observed, giving unfavorable results in terms of storage stability. Further, the zero dispersibility of the magnetic fine powder and the magnetic properties of the magnetic recording layer were by no means satisfactory.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel magnetic recording medium that overcomes the drawbacks.

Another object of the present invention is to provide a magnetic recording medium with good wear resistance.

Still another object of the present invention is to provide a magnetic recording medium with a good SZN ratio.

Yet another object of the invention is to provide a magnetic recording medium having high reproduction output.

Still another object of the present invention is to provide a high quality magnetic recording medium with excellent storage stability.

The above aspects of the present invention provide a magnetic recording medium characterized in that the magnetic recording layer on the surface of the support contains a compound represented by the following general formula CI) or [l) (hereinafter referred to as the compound of the present invention). achieved.

General formula [■] R-Z (-CH2C)T2O+nSO3M General formula [■
] In the general formulas [■] and l1l), R is an alkyl group, preferably an alkyl group having 5 to 30 atoms (e.g., a tepyl group, a dodecyl group, an octadecyl group), an alkenyl group, preferably a carbon An alkenyl group having 5 to 30 atoms (for example, an oleyl group), an aryl group (for example, a phenyl group), an anlu group (for example, a hahalumitoyl group, a per70 lohegtanoyl group) as the parent, and 10-, -S- or To-
NH-, and M is an alkali metal salt (for example, potassium J
- atom, na) IJum atom) Father is ammonium salt (e.g. NH4, NH(C2H5)5) k, n
txl represents an integer from 5 to 5.

In the present invention, each of the above groups of R may have any substituent. Typical substituents include a nitrogen atom (eg, fluorine atom), an alkyl group (eg, dodecyl group), an alkenyl group (eg, butenyl group), and an aryl group (eg, phenyl group).

Next, specific examples of the compounds of the present invention will be listed, but the compounds of the present invention are not limited to these.

[Exemplary compounds]

(11C4oHz10+cH2cH20-)-5SO5
NaOH f3) CxoHzlSOzNH+CH2
CHzO+2SO5NH4f4) CIIH29S
+ CHzCHzO+1SO5Nm (61C6F'B
C00-(CF(2(J(2095O5Nai7)
C1gH55COO(-CH2CH20+2503N
a(9) H(Cf(zcf(z)s O+ C
F(zcHzO+-,5O5Na(1(l CuH
550moCH2CH2O)2SO3Nm Synthesis examples of the compounds of the present invention are as follows.

1. Illustrated compound (synthesis example of 13 Defushial alcohol 80 g T-Put in a glass autoclave, add 0.05 g of caustic soda fine powder,
~180℃ (Heat and stir, reduce the pressure inside the container to 1 () ■ Hg 8 degrees, and add 3 atm of N2 to 70 g of ethylene oxide 1.
Add it under pressure while adjusting the flow rate, press it in, and then
Continue stirring for an hour, reduce the pressure again after cooling, and add 140 g of anhydrous sulfur.
Add slowly under gtNz. The reaction mixture was diluted with 2 ml of water (
1 O- is added little by little, and 20 g of caustic soda and 100 m of water-soluble fi are added, and after removing insoluble matter, the water is distilled off.

150 g of the desired product was obtained as a white viscous substance.

2. Synthesis example of exemplified adduct (2) 95 g of stearic acid chloride was reacted in toluene in the presence of 55 g of glycerin dimer (Yt) ethylamine, the reaction solution was washed with water in a separating funnel, and the toluene layer was concentrated. After sulfonation and treatment with an equal amount of caustic potash, the water is evaporated to dryness, yielding 150 g of a white, waxy product.

In addition to the above, the compound of the present invention can be easily synthesized according to the description in Ryohei Koide's "Synthesis of Surfactants and Their Applications" (published by Asakura Shoten).

These compounds of the present invention may be used singly or in combination of two or more.゛The magnetic fine powder used in the present invention is a fine powder in which the major axis t of the magnetic metal powder is 3.1 μ to 1 μ. Examples of the magnetic metal include metals such as iron, nickel, and cobalt, aluminum, and cobalt. , Steel Li, Magne 7 Wu, Nickel, Tin, Lead, Antimony, Helium, Bismuth,
cadmium, cal-7-woo, manganese, selenium, titanium,
Alloys of metals such as tungsten, vanadium oxide and mixtures thereof, aluminum oxide, iron oxide, steel oxide, nickel oxide, bent lead oxide, titanium oxide and magne oxide.

Examples include metal compounds containing metal oxides such as -, and ferromagnetic substances such as ferrite. Mainly used are fine powders of ferromagnetic materials such as ferrite and iron-cobalt-nickel metal.

In order to contain the compound of the present invention in the magnetic powder molecules and the stimulant together with the magnetic fine powder, at least one of the compounds of the present invention is
The stock is dissolved in a solvent such as toluene, methyl ethyl ketone, ethyl cellosolve, acetone, methanol, etc., and magnetic fine powder is immersed in the solution at a predetermined ratio, moistened with light, stirred and mixed, and then defoamed and distributed door to door. By subjecting it to drying@M, the surface of the resulting magnetic fine powder is modified, resulting in a treated magnetic powder that can be easily absorbed into an organic solvent and a binder.

Alternatively, at least 1 m of the inventive compound may be added directly to the magnetic powder fraction paint or dissolved in a suitable solvent.

The compound of the present invention is usually added to 0.00 parts by weight per 100 parts by weight of magnetic powder.
5 parts by weight to 30 parts by weight, preferably 0.5 parts by weight to lO
It is preferable to use it in the range 1 of parts by weight.

If the amount of the compound of the present invention is less than 5 parts by weight, the effect of the present invention will not be noticeable on VC, and if it exceeds 30 parts by weight, a plumping phenomenon may occur, resulting in undesirable results.

Generally, the magnetic powder fraction paint contains ferromagnetic powder, a binder, the compound of the present invention, and a cloth solvent as the main components, and in addition, if necessary, a dispersant, a moisturizer, an abrasive, an antistatic agent, etc. are added. Contains additives. This magnetic powder fraction paint is prepared by dissolving and dispersing the formulation according to the above composition in an organic solvent, and a special layer is formed on the surface of the non-magnetic support by ablating it.

Regarding the manufacturing method of @ powder dispersion 1 used in the present invention, Japanese Patent Publication No. 35-15+i', No. 39-26794, No. 43
-186, 47-213043, ImJ47-2
No. 8045, No. 147-28 + 346, No. 47-2
8 (No. 148, No. 47-31445, No. 48-111
No. 62, No. 4B-21331, No. 48-33683-
It is described in detail in various publications such as 4+ Publication and Soviet Patent Specification No. 308033.

As the binder used in the invention, conventionally known thermoplastic resins, reactive resins for thermoplastic resin casings, and mixtures thereof are used.

As for thermoplastic resin, the softening 111f is 150°C or less,
The average molecular weight is fl, (1110 to 200,0130
．． Polymerization k of about 2 u O to 2000, such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-donylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, acrylic ester-acryloni) +J Acrylate copolymer, Acrylic acid ester-M and Nyritene copolymer, Acrylic acid ester-Styrene copolymer, Methacrylic acid ester-Ac 110 Nido IJ copolymer, Methacrylic acid varnish f Roux [Vinylidene copolymer] Coalescence, methacrylic acid ester-styrene copolymer, urethane elastomer, polyvinyl fluoride, vinylidene chloride-acrylonitrile copolymer, Ac IJ lonitrile-butadiene copolymer, polyamide resin, polyvinyl butyral, cellulose tsuba conductor (cellulose acetate) gtyrate, cellulose diacetate, cellulose triacetate, cellulose propionone), nitrocellulose, etc.), styrene-butadiene copolymer, polyester resin, chlorovinyl ether-acrylic ester copolymer, amino resin, various synthetic go-based Thermoplastic resins, mixtures thereof, etc. are used.

These resins are disclosed in Japanese Patent Publications Nos. 37-6877 and 39-1.
No. 2528, No. 39-19282, No. 40-5349
No. 40-2+3907, No. 41-9463, No. 41-141) No. 59, No. 41-16985, No. 4
No. 2-6428, No. 42-11621, No. 43-46
No. 23, No. 43-15206, No. 44-2889,
No. 44-17947, No. 44-18232, No. 45
-14020, 45-14500, 47-18
No. 573, No. 47-22063, No. 47-22064
No. 47-22068, No. 47-22069, No. 47-22070, No. 4g-27886, U.S. Patent No. 3,144.352, No. 441 to 420, No. 3.49 It is described in the specifications of No. 789 and No. 3,713,887.

The thermosetting resin or reactive resin has a molecular weight of 200,000 or less in the state of a coating solution, and has a molecular weight of 200,000 or less after drying.
It becomes a p-polymer through reactions such as condensation and addition, and its molecular weight becomes infinite. Among these thermosetting resins and reactive resins, O is preferred because it does not soften or melt before the resin becomes a polymer. Specifically, example #i
7-el resin, epoxy resin, polyurethane curable resin, urea resin, melamine resin, alkyd resin, silicone resin, acrylic reaction resin, mixture of high molecular weight polyester resin and incyanate prepolymer, methacrylate copolymerization method and diynnyanate prebolimer mixture, mixture of polynispur polyol and boba incyanate, urea formaldehyde resin, low molecular weight glycol/
A mixture of molecular weight diol/ ) N phenylmethane triisocybnate, polyamine resin, and mixtures thereof.

These resins are designated as
-9779, 41-7192, 41-8016
No. 4]-14275, No. 42-18179, No. 43-12031, No. 44-281+ 23, Mukai 4
5-x4so+, 45-24902, 46-1
31++ No. 3, No. 47-22 (No. 167, No. 47-2
2 [No. 372, 47-22 (173-1, 47-2
8 (No. 145, No. 47-28048, No. 47-289
22 Yongyo Publication, U.S. Patent No. 144353, U.S. Patent No. 3,
No. 320,090, No. 3.437,510, No. 3
, No. 597,273, No. 3781.210, and No. 781,211.

These knots! It can be used alone or in combination, and other additives can be added as needed.

The mixing ratio of ferromagnetic fine powder and binder is 1 part of ferromagnetic fine powder.
1) 0 parts by weight to 1 part by weight from 10 to 400 parts by weight,
It is preferably used in a range of 30 to 2 (10 parts by weight).

If there is too much binder, the recording density of the magnetic recording medium will decrease, and if it is too little, the strength of the magnetic recording layer will be poor, resulting in undesirable situations such as decreased durability and powder falling off.

The magnetic powder-dispersed paint forming the magnetic recording layer contains additives such as a dispersant, a lubricant, an abrasive, an antistatic agent, and the like, in addition to the compound of the present invention, N-shavings, and ferromagnetic fine powder. May be added.

Dispersants that may be used include fatty acids having 12 to 18 carbon atoms, such as caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, elaidic acid, linoleic acid, and linuric acid. (RIC■
rt, R1 is an alkyl group having 11 to 17 carbon atoms);
Metal soaps consisting of alkali metals (Li, Na, etc.) or alkaline earth metals (Mg, Ca, Ba, etc.) of the above-mentioned fatty acids; lecithin, etc. are used. Other vc
Higher alcohols having 12 or more carbon atoms and VC@acid esters in addition to these can also be used. These dispersants are added in an amount of 1 to 20 parts by weight per 1 part of the IUOIl agent.

These dispersants are disclosed in Japanese Patent Publication Nos. 39-28369 and 44
-17945, 48-15 +101 Yongyo Publication, U.S. Patent No. 8587,993, 470.021
Examples of lubricants listed in the product specifications include silicone oil, carbon black, graphite, carbon black graft polymer, molybdenum disulfide, tungsten disulfide, and monobasic fatty acids with 12 to 16 carbon atoms. and the number of carbon atoms in the fatty acid, the total number of atoms is 21.
Fatty acid esters (so-called waxes) consisting of ~23 monohydric alcohols can be used. These lubricants are added in an amount of 0.2 to 20 parts by weight based on the weight of the binder 1 (11).
Publications such as -23889 and 43-81543, U.S. Patent No. λ47 Q, 021, 3.4g2,
No. 235, No. 497, 411, No. λ52108
No. 6, No. 760 to No. 62, No. 3,630,772
No. 3,634,253, &642.539
No. 3,687,725, IBM
Technieal DiselosuraBulle
tin Vol, 9, R7, Page 779
(December 1966): ELEKTRONIK
1961 Mal 2.

It is described in Page 380 etc.

The abrasives used are commonly used materials such as fused alumina, 1 corundum in silicon carbide, artificial corundum, diamond, artificial diamond, garnet, Eme+3- (main components: coranda 6 and magnetite), etc. Crab used. These abrasives have an average particle size of 0.05~
A size of 5 #≦ is used, particularly preferably 0.
It is 1~2#. It is added to these abrasives in an amount ranging from 7 to 20 parts by weight based on 00 parts by weight of binder. These abrasive materials are disclosed in Japanese Patent Application Laid-open No. 115510/1983, U.S. Pat.
96, 3,687,725, British 1% Patent No. 1,14 to 349, West German Patent (DT-P)
S) 85&211.

Conductive powders such as lamp, graphite, phyto, carbon black, carbon black graft polymer, etc.; natural surfactants such as saponin; alkylene oxide type, glue IJ yarn, grindol type, etc. Nonionic surfactants - AM alkyl amines, quaternary ammonia salts, pyridine, other heterocycles,
Phosphonilla 7-1 is a cationic surfactant such as sulfonyl group; anionic surfactant containing acidic groups such as carboxylic acid, sulfonic acid, phosphoric acid, sulfuric acid ester group, phosphoric ester group; amino acids, aminosulfonic acids, Ampholytic activators such as sulfuric acid or phosphoric acid esters of amino alcohols are used.

These surfactants that can be used as antistatic agents include U.S. Patent Nos. 4271.623 and 2.24 (1,47
No. 2, No. 2.28 & 226, No. 4676.122
No. 2.67 to No. 924, No. 2.676.975
No. 4691,566, No. 4727,860, No. 2,730,498, No. 474 S379,
4739.891, 8()6 to 101, 3.15 to 484, 3,201,253, 3,210,191, 3,294, No. 540,
Same No. 3,415,649, Same No. 441,413,
No. 3,442,654, No. 3,475,174, No. 3,545.974, OLS No. 1,942,665, British Patent No. 1, No. 077,317 and No. 1,198,450, as well as the specifications of "Synthesis of Surfactants and Their Applications" by Aryu Oda et al. (Maki Shoten 1964 edition): A., W., Bayley. Author: ``Surface Active Agents'' (International Publications 7th Incorporated T9SS edition): 'R-P, Sisley, ``Encyclopedia of Surface Active Agents Volume 2'' (Kumiriki Rupaglish Company tq64)
It is described in the scent release of ``Surfactant Handbook'' No. 6 Yuzu (Sangyo Tosho Co., Ltd., December 20, 1960).

These surface active substances may be added alone or in a mixture. Although it is used as an antistatic agent in these, it is sometimes used for other purposes, such as fractionation, improving magnetic properties, improving abrasion properties, etc. ! It may also be applied as Fusuke/Kare.

To form a magnetic recording layer, the above composition is dissolved in an organic solvent,
One cloth is applied as a coating solution onto the surface of a non-magnetic support.

Organic solvents used during coating include ketones such as acetone, methyl ethyl ketone, methyl imbutyl ketone, and cyclohexane; alcohols such as methanol, ethanol, chlornol, and butanol; methyl acetate, ethyl acetate, and acetic acid. Ester threads such as butyl, ethyl lactate, dalicol acetate monoenal ether: cyenal ether,
Glycol ether threads such as glycol dimethyl ether, glycol monoethyl ether, and dioxane; Tar threads (aromatic hydrocarbons) such as benzene, toluene, and quinceline; methylene chloride, ethylene chloride, Nishichloride, chloroform, ethylene chlorohydrin , chlorinated hydrocarbons such as dichlorobenzene, etc. can be used.

The material for the support may be any non-magnetic material, such as polyesters such as polyethylene terephthalate and polyethylene-2,6-7-talate, polypropylene such as polypropylene, and cellulose triacetate. , cellulose derivatives such as cellulose diacetate, plastics such as polycarbonate, Cu T
Non-magnetic metals such as AZ and ZB, ceramics such as glass, porcelain, and earthenware are used.

The thickness of these non-magnetic supports is film, notebook type Q)
In some cases, about 3 to 100 μm, preferably 5 to 5011
m, Tisfu, card-like case, 0.5-10
If the drum is shaped like a drum, it is cylindrical, and the shape is determined depending on the recorder used.

The non-magnetic support may be coated with a so-called back coat on the opposite side to the coated side on which a magnetic layer is provided for the purpose of preventing static electricity, preventing transfer, etc.

For the back coat Vc111m, for example, U.S. Pat. No. 4,804,401, U.S. Pat.
No. 617,378, No. 3.064676, No. λ7
No. 34772, No. 847 to No. 596, No. 4643.
No. 048, No. 2.80 Kame No. 556, No. 2.887,
No. 462, No. 2.92λ642, No. 2.997,
No. 451, same No. 〇〇7,892, same No. 3, t+41
, No. 196, No. 420 to No. 3.11, No. 3.166 of the same.
．． It is described in each specification such as No. 688.

Further, the support may be in any form such as a tape, sheet, card, tissue, or driver, and various materials may be selected as necessary depending on the form.

Magnetic fine powder and the aforementioned binder, fractional agent, I! 88 additive, abrasive, antistatic agent, solvent, etc. are kneaded to form a magnetic powder fraction paint.

To avoid crosstalk, the magnetic fine powder and each of the above-mentioned components are fed into a crosstalk machine either all at the same time or one after another. Example dl Masubun l111! There is a method in which fine magnetic powder is added to a solution containing tII, kneaded for a predetermined time, and then the remaining components are added and mixing is continued to obtain one magnetic powder fraction.

Mixed lines i! KK: As a precaution, various crosstalk devices are used.

For example, two roll mill, three roll mill, ball mill,
These include a pebble mill, a sand grinder, a Szegvari attritor, a high-speed impeller dispersion machine, a high-speed stone mill, a high-speed 1-jai percussion mill, a disperser kneader-1 high-speed mixer, a homogenizer, an ultrasonic fractionator, etc.

On crosstalk dispersion technology, written by T. C. PATTON F.
aint Flow and Pigment Dig
per+5ion (1964 John Willey
& Fj from 5ons) [stated. It is also described in U.S. Pat. No. 4,581,414 and U.S. Pat. No. 4,855,156.

Coating methods for forming a magnetic recording layer by coating the magnetic powder/I & paint onto a non-magnetic support include air doctor coating, blade coating, air knife coating, squeeze coating, impregnation coating, reverse roll coating, Transfer roll coating, gravure coating, kiss coating, cast coating, spray coating, etc. can be used, and other methods are also possible.Specific explanations of these methods can be found in "Coating Engineering" published by Asakura Shoten, pages 253-277 (1977). (published on March 20, 2015).

By such a method, the magnetic recording layer coated on the support is treated, if necessary, for orienting the magnetic fine powder in step 1. Dry the recording layer. Further, if necessary, the magnetic recording medium according to the present invention is manufactured by performing a surface smoothing process and cutting it into a desired shape.

In this case, is the orientation magnetic field crossed? II & also about 5 () with DC
Approximately 0 to 4000 force, dry m# approximately 50 to 1
(About 10°C, drying time is about 3 to 10 minutes.

A method for orienting magnetic fine powder is also described in the following patent publications and specifications.

For example, U.S. Patent No. 1.949.840-j! , same No. 4
79 to No. 359, same No. 3. (No. +01,891, No. 172.776, No. 949 to λ41, No. 147)
Specifications of Toki No. 960, No. 3,681,138, Tokuko No. 32-3427, No. 39-28368, No. 40
-23624, 40-23625, 41-13
1811, No. 48-13043, No. 4B-39722
% of each publication.

The orientation direction of the magnetic material is determined by its use. That is, in the case of sound tape, small video tape, and memory tape, it is flat in the tape length direction, and in the case of broadcast video tape, it is 300 to 9 () per length.
It is oriented with a slope of 0.

Magnetic recording media using all the compounds of the present invention have wear resistance,
It is a high quality magnetic recording medium with good storage stability and high S/N ratio and reproduction output.

The present invention will be explained in more detail below using a practical example.

The components, proportions, order of operations, etc. shown here can be changed as appropriate, and the present invention is not limited to the following examples. In addition, the following '11! In leprosy cases, all "parts" refer to "parts by weight."

Example 1 Exemplary compounds tlJ to exemplified compounds (6) of the present invention shown in Table 1 below were diluted to 5 parts of methanol (10 parts), and magnetic powder 1
00 parts were added and mixed and dispersed. After that, it was filtered, air-dried, and then dried under reduced pressure at 80°C.
’.

Below is the margin: Table 1 A small amount of each of the treated magnetic powders NELI to 6 above is applied.
When seven latching tests were carried out in a water-toluene system, the treated magnetic powder was completely transferred to the organic layer. The fact that water JIiK remains in the untreated magnetic powder indicates that the surface of the magnetic powder has been modified by the treated magnetic powder so that it can be well wetted into the organic solvent-based binding network. .

A magnetic tape was prepared with the following composition using the treated magnetic powder N11-6 obtained above.

All of the above composition was put into a ball mill, and after thorough mixing, a blackish brown magnetic powder fraction paint was obtained. This paint t-15
A magnetic mt of 1200 gauss was applied to a piece of polyethylene terephthalate film ffi of 1200 gauss, and the mixture was coated to a dry thickness of 6 µm and dried.

The thus obtained wide magnetic wave was supercalendered and slit to a width of 12.7 cm to obtain a videotape.
The tapes prepared according to N116 were each designated as unexploded #J [slope 1 to m6.

Example 2 The exemplified compounds ill to ll compounds (6) of the present invention shown in Table 2 below were diluted with 500 parts of methanol to form a magnetic alloy (
100 parts of Fe-Co-Ni) were added and mixed and dispersed.

After that, it was filtered, air-dried, and then dried under reduced pressure to prepare all of the treated magnetic powders Hn7 to Hn12 shown in Table 2.

Table 2 (Table 2) Using the thus obtained treated magnetic powder Na 7 to 12 t-, a magnetic powder component I & paint having the following composition was prepared.

After the above composition was thoroughly mixed and dispersed in a ball mill, 3 parts of tolylene diylananate was added and mixed uniformly to obtain a magnetic coating material. This paint't-15μ polyethylene terephthalate pile was applied to one side of the five sides [VC@cloth, while applying a magnetic field of 12+10 Gauss, so that the drying thickness was 5μ.
Dry. In this way, all samples with a hot water pressure width of 7 to 12 tons were prepared in the same manner as the inventive sample Nal of Example 1.

Example 3 The above composition was placed in a ball mill, thoroughly mixed and dispersed, and then a blackish brown magnetic powder fraction paint was obtained. Using this material, a biotape was obtained in the same manner as the sample of the present invention. Is this tape a sample of the present invention? 4113.

Comparative Example 1 Untreated CO instead of surface-modified treated magnetic powder
A videotape was prepared in the same manner as the sample Nal of the present invention in Example 1 using 9 lines containing Fs50+4. This is designated as comparative sample N11l.

Comparison f112 Example 2 except that an untreated magnetic alloy (Fe-Co-Ni) was used instead of the surface-modified magnetic powder.
A videotape was prepared in the same manner as in Sample 7. This will be referred to as comparative sample Taki 2.

Comparative Example 3 After the above composition was thoroughly mixed and dispersed in a ball mill, a blackish brown magnetic powder dispersed paint was obtained. Using this paint, a videotape was obtained in the same manner as Sample Floor 6 of the present invention in Example 2. This conference will be designated as Comparison Test Slope 3.

Comparative Example 4 The above composition was thoroughly mixed and dispersed in a T-ball mill to obtain magnetic powder I and paint.

Using this paint, a videotape was obtained in the same manner as in Example 20 and Invention Sample 6. This tape will be referred to as Comparative Sample 4.

The comparative test results for each of these samples are summarized in Table 3.

I-Margin Note (a) RF small output, 4M using VTR deck for measurement
The small RF output at IIz was measured and expressed as a relative value with the output of the comparison sample NIL1 being 11-0.

(b) A 5 m long tape was repeatedly slid back and forth at a speed of t 7 m/see using an abrasion resistant comb and a simulated head tube, and the subsequent tape #J was evaluated visually and with a microscope.

(e) Storage stability was determined by the occurrence of pecking after being left for 24 hours at a humidity of 80°C and a temperature of 40°C.

From the above results, it can be seen that the magnetic recording medium according to the present invention is a high-density magnetic recording medium having better wear resistance and storage stability and higher reproduction output than conventional ones.

Patent applicant: Konishiroku Photo Industry Co., Ltd. Agent Patent attorney: Nobuaki Sakaguchi (and one other person) Procedural amendment (voluntary) April 9, 1980 Commissioner of the Patent Office Toshi Shimada Saiki, Showa 1999 Application No. 3, amendment Relationship with the case of a person who does

Claims (1)

[Scope of Claims] A magnetic recording medium characterized in that a magnetic recording layer on a support surface contains a compound represented by the following general formula i) or CI. General formula [■] R-Z (-CHzCHzO+n805M general formula [) [In the formula, RFi is a substituted or unsubstituted alkyl group, alkenyl group, aryl group or acyl group, 2 is 10-, -
S- or -Nf (-1M represents an alkali metal salt or ammonium salt and an integer from ntf1 to 5.)