JPH10124852A - Magnetic recording medium and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic recording medium which suppresses the corrosion of a magnetic head surface and lessens output attenuation and a process for producing the same. SOLUTION: The magnetic layer of the magnetic recording medium constituted by forming the magnetic layer consisting essentially of magnetic powder and binder on a nonmagnetic base contains anion exchanging intercalation compds., such as hydrotalcite group ores. The preferable content to the anion exchanging intercalation compds. is >=1 to <=10 pts.wt. to 100 pts.wt. magnetic powder. The process for producing the magnetic recording medium has a magnetic layer forming stage for dissolving the magnetic powder, the binder and the anion exchanging intercalation compds., such as hydrotalcite group ores into a solvent to manufacture a magnetic coating material and applying this magnetic coating material on the nonmagnetic base. The preferable adding amt. of the hydrotalcite group ores is >=1 to <=10 pts.wt. to 100 pts.wt. magnetic powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium and a method for manufacturing the same, and more particularly, to a magnetic recording medium in which a nonmagnetic support is provided with a magnetic layer mainly composed of a magnetic powder and a binder, and a method for manufacturing the same. About the method.

[0002]

2. Description of the Related Art In recent years, in the field of magnetic recording, higher picture quality of video equipment has been promoted, or analog recording has been changed to digital recording, etc., and magnetic recording / reproducing apparatuses have been moving toward shorter wavelength recording. . Therefore, the magnetic recording medium must have good electromagnetic conversion characteristics, have running durability that can withstand long-time and multiple use, have low output attenuation after running, and have storage stability. In addition, high reliability is required which has both of not damaging the magnetic head during recording and reproduction.

On the surface of a magnetic head on which recording and reproduction have been performed to some extent, magnetic powder, additives, binders, and the like, which have fallen off from a magnetic layer or a back coat layer of a magnetic recording medium, adhere to and accumulate, resulting in a large spacing loss. For example, the recording / reproducing and erasing characteristics may be deteriorated. Sulfate ions, chloride ions, and the like are eluted from the magnetic powder, additives or binders deposited on the surface of the magnetic head to corrode the surface of the magnetic head, possibly deteriorating the recording / reproducing and erasing characteristics. was there.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to prevent elution of sulfate ions and chloride ions from magnetic powder, additives or binders constituting a magnetic layer of a magnetic tape, and to prevent the magnetic head surface from being eluted. An object of the present invention is to provide a magnetic recording medium that suppresses corrosion and reduces output attenuation, and a method for manufacturing the same.

[0005]

In order to solve the above-mentioned problems, a magnetic recording medium according to the present invention comprises a non-magnetic support having a magnetic layer mainly composed of a magnetic powder and a binder formed on a non-magnetic support. The magnetic layer contains an anion exchangeable interlayer compound such as a hydrotalcite group mineral. The desirable content of the anion exchangeable intercalation compound is 1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the magnetic powder.

In the method for producing a magnetic recording medium of the present invention, a magnetic paint is prepared by dissolving a magnetic powder, a binder and an anion-exchangeable interlayer compound such as a hydrotalcite group mineral in a solvent. A step of forming a magnetic layer by coating on a magnetic support. A desirable addition amount of the anion exchangeable intercalation compound is 1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the magnetic powder, and the solvent has water of 2 parts by weight or more.

According to the above-mentioned means, sulfate ions and chloride ions eluted from the magnetic powder, additives, binders and the like constituting the magnetic layer are retained by the anion exchangeable intercalation compound contained in the magnetic layer. Has the effect of suppressing elution out of the magnetic layer. Therefore, corrosion of the magnetic head surface and the like by these ions can be suppressed.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The anion-exchange intercalation compound to be contained in the magnetic layer of the present invention is a kind of 0: 1 type clay mineral, and is preferably a layered hydrotalcite group mineral composed of AlO ₆ octahedral sheet. Can be exemplified. A typical example of hydrotalcite group minerals is natural hydrotalcite represented by the general formula Mg ₆ Al ₂ (OH) ₁₆ · CO ₃ · 4H ₂ O, which is slightly different in composition from natural hydrotalcite Commercially available synthetic hydrotalcite can be exemplified. It is also possible to use a hydrated oxide such as titanium, zirconium, lanthanum, bismuth or phosphorus hydroxide as an anion-exchangeable intercalation compound other than the hydrotalcite group minerals described above.

[0009] exchangeable anions are present between layers of anion exchange intercalation compound used in the present invention, solvated high dielectric constant medium such as water, alcohol tends to inorganic anions, in one example NO ₃ ^- , SO ₄ ^2- , Cl
Examples thereof include hydrophilic organic anions such as O ₄ ⁻ , Fe (CN) ₆ ⁴⁻ , heteropolyacid ions and lower carboxylate ions. Note that higher carboxylate ions tend to make it difficult to solvate between layers as compared with the above-mentioned anions.

In order to improve the dispersibility of the anion-exchange intercalation compound and the swelling property of the anion-exchange intercalation compound in a non-aqueous solvent, a part of the exchangeable anions of the anion-exchange intercalation compound is reduced. An organic anion having a spreading effect (pillar effect) or an effect of partially hydrophobizing the interlayer may be substituted. Examples of such an organic anion include a carboxylate anion, a sulfonate anion, an ester anion, and a phosphate anion. Generally, the organic anion has an alkyl group or an alkenyl group, and when these carbon atoms are small, the pillar effect is not sufficient,
It becomes difficult to secure a layer as a fixing seat (exchangeable inorganic cation). If the number of carbon atoms is too large, substitution will not be performed. Therefore, the carbon number of the organic anion is preferably 5 or more and 10 or less.

The binder contained in the magnetic layer is used for the purpose of imparting running durability, flexibility and toughness to the magnetic recording medium and improving the adhesion to the non-magnetic support, and the like. , A thermosetting resin, a reactive resin and the like can be used. The weight average molecular weight of the binder contained in the magnetic layer of the present invention is preferably from 15,000 to 200,000. Examples of thermoplastic resins include vinyl chloride, vinyl acetate, vinyl chloride-vinyl acetate copolymer,
Vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, acrylate-acrylonitrile copolymer, acrylate-vinyl chloride-vinylidene chloride copolymer, acrylate-vinylidene chloride copolymer, methacryl Acid ester-vinylidene chloride copolymer, methacrylic ester-vinyl chloride copolymer, methacrylic ester-ethylene copolymer, polyvinyl fluoride, vinylidene chloride-acrylonitrile copolymer, acrylonitrile-butadiene copolymer, polyamide resin, Polyvinyl butyral, cellulose derivatives (cellulose acetate butyrate, cellulose diacetate, cellulose triacetate, cellulose propionate, nitrocellulose), styrene butadiene copolymer, polyurethane Tan resin include polyester resins, amino resins, synthetic rubbers and the like. Examples of thermosetting resins and reactive resins include phenolic resins, epoxy resins, polyurethane curable resins, urea resins, melamine resins, alkyd resins, silicone resins,
Examples thereof include a polyamine resin and a urea formaldehyde resin.

[0012] Because the binding agent as described above to improve the dispersibility of the magnetic _{powder, -SO 3 M, -OSO 3 M} , -COO
Polar functional groups such as M and -PO (OM) ₂ may be introduced. Note that M in the formula represents a hydrogen atom or an alkali metal such as lithium, potassium, and sodium. -NR ₁ R ₂ as the polar functional ^{_{group, -N + R 1 R 2 R}} 3 X
A side chain type having a terminal group such as ^- ,> N ⁺ R ₁ R
₂ X ^- that of main-chain as, -OH, -SH, -C
Those having N, an epoxy group and the like can be mentioned.
In the formula, R ₁ R ₂ R ₃ represents a hydrogen atom or a hydrocarbon group, and X ⁻ represents a halogen element ion such as fluorine, chlorine, bromine or iodine, or an inorganic or organic ion. The addition amount of these polar functional groups is 10 ^-1 mol / g or more and 10 ^-8 m.
ol / g or less, preferably 10 ⁻² mol / g or more and 10 ⁻⁶ mol / g or less.

The above-mentioned binders may be used alone or in combination of two or more. The addition amount of the binder is 1 part by weight or more and 100 parts by weight or less, preferably 10 parts by weight or more and 50 parts by weight or less based on 100 parts by weight of the nonmagnetic powder. If the amount of the binder is too large, plastic flow of the coating film may occur due to repeated sliding of the magnetic recording medium with respect to the magnetic head or the like, which may cause a decrease in running durability. There is a possibility that the dispersibility of the magnetic powder deteriorates and the bonding strength in the coating film decreases.

In the present invention, it is possible to use a polyisocyanate which has a crosslinking effect on the binder. Examples of the polyisocyanate include toluene diisocyanate, an adduct of toluene diisocyanate, an alkylene diisocyanate, an adduct of alkylene diisocyanate, and the like. The amount of the polyisocyanate to be added is 5 to 80 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the binder.

Examples of the magnetic powder contained in the magnetic layer of the present invention include metals such as Fe, Co, and Ni;
e-Ni, Fe-Al, Fe-Ni-Al, Fe-Al
-P, Fe-Ni-Si-Al, Fe-Ni-Si-A
1-Mn, Fe-Mn-Zn, Fe-Ni-Zn, Co
-Ni, Co-P, Fe-Co-Ni, Fe-Co-N
i-Cr, Fe-Co-Ni-P, Fe-Co-B, F
e-Co-Cr-B, Mn-Bi, Mn-Al, Fe-
Examples thereof include alloys such as Co-V, iron nitride, and iron carbide. In order to prevent sintering during reduction and maintain the shape,
Even if an appropriate amount of a light metal element such as 1, Si, P, or B is contained, the effect of the present invention is not hindered. Also, γ-
Fe ₂ O ₃ , Fe ₃ O ₄ , γ-Fe ₂ O ₃ and Fe ₃ O ₄
, A Co-containing γ-Fe ₂ O ₃ , C
o-containing Fe ₃ O ₄ , Co-containing γ-Fe ₂ O ₃ and Fe ₃ O
_Also, oxides in which one or more metal elements, for example, Te, Sb, Fe, B and the like are contained in CrO ₂ , a beltlide compound with _4, and the like can be exemplified. Further, hexagonal plate-like ferrite can also be used, and M type, W type, Y
Type, Z type barium ferrite, strontium ferrite, calcium ferrite, lead ferrite, and Co-Ti, Co-Ti-Z for controlling the coercive force.
n, Co-Ti-Nb, Co-Ti-Zn-Nb, Cu
Examples to which -Zr, Ni-Ti or the like is added can also be exemplified. These magnetic powders can be used alone or in combination of two or more.

[0016] The specific surface area of the magnetic powder usable in the present invention is not more than 20 m ² / g or more 80m ² / g, 30m ² /
g to 70 m ² / g is preferred. High-density recording is possible with a magnetic powder finer in this range.
A magnetic recording medium having excellent noise characteristics such as the / N ratio can be obtained. The magnetic powder has a major axis length of 0.05 μm or more and 0.30 μm or less, and preferably has an axial ratio of 2 or more and 15 or less. If the major axis length is outside the above range, uniform dispersion in the coating material for the magnetic layer may be difficult, and noise characteristics may be deteriorated. If the axial ratio is out of the above range, the orientation of the magnetic powder may be reduced, leading to a decrease in output or a decrease in output during short-wavelength recording. In the case of plate-like ferrite, the plate diameter is 0.01 μm or more and 0.5 μm or less, and the plate thickness is 0.001 μm.
It is preferably not less than 0.2 μm and not more than 0.2 μm.

Examples of the abrasive particles contained in the magnetic layer include aluminum oxide (α, β, γ), chromium oxide, silicon carbide, diamond, garnet, emery,
Examples include boron nitride, titanium carbide, titanium carbide, titanium oxide (rutile, anatase) and the like.
The content of the abrasive particles is at most 20 parts by weight, preferably at most 10 parts by weight, per 100 parts by weight of the nonmagnetic powder. Mohs hardness is 4 or more, preferably 5
That is all. Further, the specific gravity is 2 g / cm ³ or more and 6 g / cm.
³ or less, preferably 3 g / cm ³ or more and 5 g / cm ^3
3 or less. The average particle size is 0.5 μm or less, preferably 0.3 μm or less.

In the present invention, a lubricant or a surfactant can be contained in the magnetic layer as required. Examples of lubricants include graphite, molybdenum disulfide, tungsten disulfide, silicone oil, fatty acids having 10 to 22 carbon atoms, fatty acid esters composed of alcohols having 2 to 26 carbon atoms, terpene compounds, and oligomers thereof. Can be exemplified. Nonionic, anionic, cationic and amphoteric surfactants can be exemplified as examples of the surfactant.

Examples of the nonmagnetic support include polyesters such as polyethylene terephthalate and polyethylene-2,6-naphthalate, polyolefins such as polypropylene, celluloses such as cellulose triacetate and cellulose diacetate, vinyl resins, and polyimides. And a support formed of a polymer material typified by polycarbonates, metal, glass, ceramics and the like.

The formation of the magnetic layer on the non-magnetic support is performed by applying a magnetic paint obtained by dissolving a mixed base material of a magnetic powder and a binder in a solvent to the non-magnetic support and drying it. Examples of solvents include ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; alcohol solvents such as methanol, ethanol, and propanol; methyl acetate, ethyl acetate, butyl acetate, butyl acetate, propyl acetate, ethyl lactate, and ethylene glycol acetate. Ester solvents such as diethylene glycol dimethyl ether, 2-ethoxyethanol, ether solvents such as tetrahydrofuran and dioxane, benzene, toluene, aromatic hydrocarbon solvents such as xylene, methylene chloride, ethylene chloride, carbon tetrachloride, chloroform,
Examples thereof include halogenated hydrocarbon solvents such as chlorobenzene. Further, water may be used in a range in which the resin can be dissolved.

According to the present invention, a magnetic recording medium and a magnetic layer having a back coat layer formed on the opposite surface of a non-magnetic support having a magnetic layer formed thereon as necessary to improve runnability, prevent charging and prevent transfer. The present invention can be applied to any of magnetic recording media having an undercoat layer formed thereon for improving the adhesive strength between the magnetic recording medium and the nonmagnetic support.

Hereinafter, specific examples of the present invention and comparative examples which are compared with the examples are examples of magnetic recording media.
A magnetic tape having a width of mm is manufactured, and this will be described with reference to FIGS. It goes without saying that the present invention is not limited to the embodiments described below.

Example 1 First, the following compositions were mixed and kneaded with an extruder, and a solvent was further added and preliminarily dispersed with a disper.
The mixture was dispersed in a sand mill for 4 hours to prepare an interlayer compound paint.

100 parts by weight of an anion-exchangeable interlayer compound hydrotalcite (trade name KW-2200, manufactured by Kyowa Chemical Co., Ltd.) 10 parts by weight of vinyl chloride copolymer (trade name: MR-110, manufactured by Zeon Corporation) Polyester polyurethane resin 10 parts by weight (trade name: UR-8200, manufactured by Toyobo) Methyl ethyl ketone 305 parts by weight Toluene 183 parts by weight Cyclohexanone 122 parts by weight Water 70 parts by weight

Next, the following compositions are mixed and kneaded with an extruder, a solvent is added, and the mixture is preliminarily dispersed with a disper. Then, the prepared interlayer compound paint is added to 100 parts by weight of the magnetic paint. 82 parts by weight (magnetic powder 100
(Corresponds to the ratio of 1 part by weight of the intercalation compound to the parts by weight)
Was added and dispersed by a sand mill for 4 hours to prepare a magnetic paint.

100 parts by weight of Fe-based metal magnetic powder (coercive force 126 kA / m, saturation magnetization 122 Am ² / Kg, specific surface area 55 m ² / g, major axis length 0.25 μm, needle ratio 10) 10 parts by weight (trade name: MR-110, manufactured by Zeon Corporation) 10 parts by weight of polyester polyurethane resin (trade name: UR-8200, manufactured by Toyobo Co., Ltd.) 10 parts by weight of α-Al ₂ O ₃ 1 part by weight of stearic acid 1 part by weight butyl stearate 1 part by weight Methyl ethyl ketone 140 parts by weight Toluene 83 parts by weight Cyclohexanone 54 parts by weight Water 31 parts by weight

Next, a polyisocyanate was added to the magnetic paint.
It was applied to a non-magnetic support, a 7 μm-thick polyethylene terephthalate film, using a die coater so that the dried magnetic layer had a thickness of 3 μm. Then, the magnetic layer was subjected to an orientation treatment by a solenoid coil, dried, calendered, and then cured.

Next, a back coat paint was prepared from the following composition, and this back coat paint was applied to the opposite surface of the polyethylene terephthalate film on which the magnetic layer was formed so that the layer thickness after drying was 0.5 μm. Then, a curing treatment was performed. Thereafter, the obtained magnetic recording medium was slit to complete a magnetic tape having a width of 8 mm.

100 parts by weight of carbon black (trade name: Asahi # 35, manufactured by Asahi Carbon Co.) 100 parts by weight of polyester polyurethane (trade name: N-2304, manufactured by Nippon Polyurethane) 500 parts by weight of methyl ethyl ketone 500 parts by weight of toluene

Example 2 In this example, 9.1 parts by weight of an interlayer compound was added to 100 parts by weight of a magnetic paint (corresponding to a ratio of 5 parts by weight of an interlayer compound to 100 parts by weight of a magnetic powder). A magnetic tape was completed in the same manner as in Example 1 except that a magnetic paint was prepared.

Example 3 In this example, 18.2 parts by weight of an interlayer compound paint was added to 100 parts by weight of a magnetic paint (corresponding to a ratio of 10 parts by weight of an interlayer compound to 100 parts by weight of a magnetic powder). A magnetic tape was completed in the same manner as in Example 1 except that a magnetic paint was prepared.

Comparative Example 1 In this comparative example, a magnetic tape was completed in the same manner as in Example 1 except that no interlayer compound paint was added to the magnetic paint.

Comparative Example 2 In this comparative example, 0.55 parts by weight of the intercalation compound paint was added to 100 parts by weight of the magnetic paint (corresponding to a ratio of 0.3 part by weight of the intercalation compound to 100 parts by weight of the magnetic powder). A magnetic tape was completed in the same manner as in Example 1 except that a magnetic paint was additionally prepared.

Comparative Example 3 In this comparative example, 27.3 parts by weight of an interlayer compound paint was added to 100 parts by weight of a magnetic paint (corresponding to a ratio of 15 parts by weight of an interlayer compound to 100 parts by weight of magnetic powder). A magnetic tape was completed in the same manner as in Example 1 except that a magnetic paint was prepared.

Example 4 In this example, the amount of water was 2% by weight based on the total solvent contained in the composition of the intercalation compound paint and the magnetic paint. First, the following compositions were mixed and kneaded with an extruder, further added with a solvent, preliminarily dispersed with a disper, and then dispersed with a sand mill for 4 hours to prepare an interlayer compound paint.

100 parts by weight of an anion-exchangeable interlayer compound hydrotalcite (trade name KW-2200, manufactured by Kyowa Chemical Co., Ltd.) 10 parts by weight of vinyl chloride copolymer (trade name: MR-110, manufactured by Zeon Corporation) Polyester polyurethane resin 10 parts by weight (trade name: UR-8200, manufactured by Toyobo) Methyl ethyl ketone 333 parts by weight Toluene 200 parts by weight Cyclohexanone 133 parts by weight Water 14 parts by weight

Next, the following composition was mixed, kneaded with an extruder, further added with a solvent, and preliminarily dispersed with a disper. Then, the already prepared interlayer compound coating material was added to 100 parts by weight of the magnetic coating material. 3 parts by weight (magnetic powder 100
(Corresponding to a ratio of 15 parts by weight of the intercalation compound to the parts by weight) and dispersed by a sand mill for 4 hours to prepare a magnetic coating material.

100 parts by weight of Fe-based metal magnetic powder (coercive force: 126 kA / m, saturation magnetization: 122 Am ² / Kg, specific surface area: 55 m ² / g, major axis length: 0.25 μm, needle ratio: 10) 10 parts by weight (trade name: MR-110, manufactured by Zeon Corporation) 10 parts by weight of polyester polyurethane resin (trade name: UR-8200, manufactured by Toyobo Co., Ltd.) 10 parts by weight of α-Al ₂ O ₃ 1 part by weight of stearic acid 1 part by weight butyl stearate 1 part by weight Methyl ethyl ketone 151 parts by weight Toluene 91 parts by weight Cyclohexanone 60 parts by weight Water 6 parts by weight

Hereinafter, since it is the same as the case shown in the first embodiment, the description is omitted.

Example 5 In this example, water was not contained in any of the compositions of the intercalation compound paint and the magnetic paint. First, the following compositions were mixed and kneaded with an extruder, further added with a solvent, preliminarily dispersed with a disper, and then dispersed with a sand mill for 4 hours to prepare an interlayer compound paint.

100 parts by weight of an anion-exchangeable interlayer compound hydrotalcite (trade name KW-2200, manufactured by Kyowa Chemical Co., Ltd.) 10 parts by weight of vinyl chloride copolymer (trade name: MR-110, manufactured by Zeon Corporation) Polyester polyurethane resin 10 parts by weight (trade name: UR-8200, manufactured by Toyobo) Methyl ethyl ketone 340 parts by weight Toluene 204 parts by weight Cyclohexanone 136 parts by weight

Next, the following compositions were mixed and kneaded with an extruder, and after adding a solvent and preliminarily dispersing with a disper, the already prepared interlayer compound coating material was added to 100 parts by weight of the magnetic coating material. 3 parts by weight (magnetic powder 100
(Corresponding to a ratio of 15 parts by weight of the intercalation compound to the parts by weight) and dispersed by a sand mill for 4 hours to prepare a magnetic coating material.

100 parts by weight of Fe-based metal magnetic powder (coercive force: 126 kA / m, saturation magnetization: 122 Am ² / Kg, specific surface area: 55 m ² / g, major axis length: 0.25 μm, needle ratio: 10) 10 parts by weight (trade name: MR-110, manufactured by Zeon Corporation) 10 parts by weight of polyester polyurethane resin (trade name: UR-8200, manufactured by Toyobo Co., Ltd.) 10 parts by weight of α-Al ₂ O ₃ 1 part by weight of stearic acid 1 part by weight butyl stearate 1 part by weight Methyl ethyl ketone 154 parts by weight Toluene 92 parts by weight Cyclohexanone 62 parts by weight

The following is the same as the case shown in the first embodiment, and a description thereof will be omitted.

As described above, Examples 1 to 5 and Comparative Examples 1 to 3 were evaluated under the following conditions, and the results are shown in Table 1.
FIG. 1 is a graph showing the relationship between the intercalation compound addition amount and the output attenuation based on the results of Table 1, and shows the relationship between the water addition amount and the output attenuation in Examples 2, 4 and 5. FIG. 2 is a graph. The measurement was performed in a constant temperature chamber at room temperature of 40 ° C. and humidity of 80%.

Magnetic properties The coercive force, saturation magnetic flux density and squareness ratio were measured using a sample vibration magnetometer (manufactured by Toei Kogyo Co., Ltd.).

Gloss The gloss was measured according to Gloss 45 ° specified in JIS-8741. That is, using a gloss meter (manufactured by Nippon Denshoku Industries Co., Ltd.), the glossiness measured at an incident angle of light of 45 ° was relative-converted with the glossiness of the reference plate similarly measured as 100%.

After the RF output at the beginning of the output attenuation is set as the initial output, the magnetic tape is
After running for 0 minutes, rewind and regenerate again.
The F output was defined as the output after traveling. Then, (initial output)-(output after traveling) was measured for output attenuation in dB.

[0049]

[Table 1]

As is clear from Table 1 and FIG. 1, when the amount of the anion-exchangeable intercalation compound is from 1 to 10 parts by weight based on 100 parts by weight of the magnetic powder, the output attenuation can be reduced. At the same time, both the glossiness and the magnetic properties were practically satisfactory. Further, as is clear from Table 1 and FIG. 2, the addition of water was also effective for the output attenuation.

[0051]

According to the magnetic recording medium and the method of manufacturing the same of the present invention, elution of sulfate ions and chloride ions from magnetic powders, additives or binders constituting a magnetic layer of a magnetic tape is prevented, It is possible to provide a magnetic recording medium that suppresses corrosion on the surface of a magnetic head and reduces output attenuation, and a method for manufacturing the same.

[Brief description of the drawings]

FIG. 1 is a graph showing a relationship between an intercalation compound addition amount and output attenuation in Examples 1 to 3 to which the present invention is applied and Comparative Examples 1 to 3 in comparison with the examples.

FIG. 2 shows Examples 2, 4 and 5 to which the present invention is applied.
It is the graph which showed the relationship between the amount of water addition and output attenuation.

Claims (7)

[Claims] 1. A magnetic recording medium in which a magnetic layer mainly composed of a magnetic powder and a binder is formed on a non-magnetic support, wherein the magnetic layer contains an anion-exchange intercalation compound. Magnetic recording medium. 2. The magnetic recording medium according to claim 1, wherein the magnetic powder contains 1 to 10 parts by weight of the anion exchangeable intercalation compound with respect to 100 parts by weight of the magnetic powder. 3. The method according to claim 1, wherein the anion exchangeable intercalation compound is a hydrotalcite group mineral.
3. The magnetic recording medium according to claim 1. 4. A step of dissolving a magnetic powder, a binder, and an anion-exchange intercalation compound in a solvent to prepare a magnetic paint, and applying the magnetic paint to a non-magnetic support to form a magnetic layer. A method for manufacturing a recording medium, comprising: 5. The method for producing a magnetic recording medium according to claim 4, wherein the amount of the anion exchangeable intercalation compound is 1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the magnetic powder. 6. The method according to claim 4, wherein the anion exchangeable intercalation compound is a hydrotalcite group mineral.
3. The method for manufacturing a magnetic recording medium according to claim 1. 7. The method according to claim 4, wherein the solvent has water of 2% by weight or more.