JPH1036866A - Lubricating substance and magnetic recording medium using this lubricating substance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spherical compound having two or more polar groups in a molecule, a fluorine compound having one or more polar groups in a molecule, or a carbon compound having one or more polar groups in a molecule. A lubricating substance composed of a mixture with a hydrogen compound enables sliding with low friction and low abrasion between two solids that contact each other regardless of high speed, low speed, high load, and low load. A magnetic recording medium having excellent durability by being present inside or on the surface is obtained. A mixture of a spherical compound having two or more polar groups in a molecule and a fluorine compound having one or more polar groups in a molecule or a hydrocarbon compound having one or more polar groups in a molecule. Lubricating substance, and a magnetic recording medium in which the lubricating substance is present inside or on the surface of a magnetic layer

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating substance and a magnetic recording medium using the lubricating substance, and more particularly, to a low friction between two solids contacting at high speed, low speed, high load and low load. A lubricating substance that slides with low wear,
The present invention relates to a magnetic recording medium using the lubricating substance and having excellent durability.

[0002]

2. Description of the Related Art Hardening of a solid surface and development of a lubricating material have been carried out for the purpose of extending the service period of equipment and devices by sliding between two solids in contact with low friction and low wear. Particularly in the field of OA equipment, there is a strong demand for size reduction, and precision mechanisms have been adopted for sliding parts year by year. For future equipment in which precision parts slide continuously or intermittently in a wide range of environments, the As described above, it is necessary to reduce the friction and abrasion at the start, at the end, and at the time of sliding, and to reduce the load on the motor and the like. Therefore, in the protective lubrication system, a hard and hard to wear surface layer is provided at a sliding portion, and a grease or oil-like semi-solid or liquid lubricating substance is used as a lubricating substance.

[0003] A magnetic recording medium formed by applying a magnetic paint comprising a magnetic powder, a binder resin, an organic solvent and other necessary components on a non-magnetic support and drying the same is run while contacting a magnetic head or the like. Therefore, it is required that the magnetic layer is easily worn, the coefficient of friction of the magnetic layer is small, and the durability is excellent. Further, a ferromagnetic metal thin film type magnetic recording medium made by depositing a ferromagnetic metal or an alloy thereof on a non-magnetic support by vacuum evaporation or the like,
Compared to coated magnetic recording media, it is easier to increase the coercive force and reduce the thickness of the magnetic layer, and it has excellent high-density recording characteristics, but does not use a tough binder resin, and has a ferromagnetic metal thin film layer and protection. Since the surface of the film has good surface smoothness, the coefficient of friction with the magnetic head becomes large, so that the film is susceptible to wear and damage, and the durability and running properties are poor.

Thus, for example, in the case of a magnetic recording medium,
On the ferromagnetic metal thin film layer, a fluorine-based lubricating substance having at least one polar group such as an amino group, a carboxyl group, a phosphoric acid group, a hydroxyl group, a fluoroalkyl group and an aliphatic alkyl group at the molecular terminal is provided. (Japanese Unexamined Patent Publication No.
1-1107529, JP-A-62-92225, JP-A-62-92226, JP-A-62-92227, JP-A-61-107527, JP-A-61-107528
And Japanese Patent Application Laid-Open No. Sho 60-229221), and the durability and running properties are improved by including these fluorine-based lubricating substances in a magnetic layer.

[0005]

However, in precision instruments in which contact portions have been smoothed, high-speed, low-speed,
Low friction between two solids contacting regardless of high load and low load,
A lubricating substance that can be slid with low wear has not been obtained, and the problem of poor starting or accidental sudden increase in frictional force during sliding cannot be avoided. Further, in a magnetic recording medium, when a fluorine-based lubricating substance is present on a ferromagnetic metal thin film layer or when a fluorine-based lubricating substance is contained in a magnetic layer, durability and running properties are improved, Not enough yet.

The present invention has been made in view of such a situation, and even in future precision equipment in which the contact portion is being smoothed, the contact is made irrespective of high speed, low speed, high load, and low load.
Obtain a lubricating substance that can slide between solids with low friction and low abrasion. Also, by using this lubricating substance for a magnetic recording medium, we aim to obtain a magnetic recording medium with excellent durability. Things.

[0007]

According to the present invention, there is provided a lubricating substance comprising: a spherical compound having two or more polar groups in a molecule;
It is composed of a fluorine compound having one or more polar groups in the molecule or a mixture with a hydrocarbon compound having one or more polar groups in the molecule.

Further, the magnetic recording medium of the present invention has a spherical compound having two or more polar groups in a molecule and a fluorine compound having one or more polar groups in a molecule inside or on the surface of the magnetic layer. A lubricating substance comprising a mixture with a hydrocarbon compound having one or more polar groups in the molecule is present.

Further, the magnetic recording medium of the present invention comprises a layer comprising a spherical compound having two or more polar groups in a molecule on a magnetic layer and a fluorine compound having one or more polar groups in a molecule. A lubricant layer is formed by laminating a layer made of a hydrocarbon compound having one or more polar groups in the molecule.

[0010]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a spherical compound having two or more polar groups in a molecule, a fluorine compound having one or more polar groups in a molecule or one or more polar groups in a molecule are used. A lubricating substance comprising a mixture with a hydrocarbon compound having the compound has an excellent lubricating function when each compound is mixed in a hydrogen-bonded state, and further has an excellent load resistance because it contains a spherical compound. Also, because it has a polar group in the molecule, it is strongly adsorbed on the solid surface by the action of this polar group,
By forming a dense lubricating film, it is possible to slide with low friction and low abrasion between two solids contacting regardless of high speed, low speed, high load and low load.

When this kind of lubricating substance is used for a magnetic recording medium, it is strongly adsorbed on the surface of the magnetic layer or the surface of the protective film due to the action of a polar group in the molecule and stably exists. And the lubrication function and the load resistance are sufficiently exhibited, and the durability of the magnetic recording medium can be sufficiently improved.

Further, a layer composed of a spherical compound having two or more polar groups in the molecule and a layer composed of a fluorine compound having one or more polar groups in the molecule or one or more polar groups in the molecule. The lubricant layer provided by laminating a layer made of a hydrocarbon compound having the compound is strongly adsorbed on the surface of the magnetic layer or the surface of the protective film due to the action of the polar group in the molecule of each compound, and exists stably. The lubrication function and load resistance are sufficiently exhibited, and the durability of the magnetic recording medium is sufficiently improved.

Such a spherical compound having two or more polar groups in a molecule, a fluorine compound having one or more polar groups in a molecule, or a hydrocarbon compound having one or more polar groups in a molecule. The lubricating substance of the present invention comprising a mixture of the spherical compound is a dendrimer having two or more polar groups in the molecule, a hyperbranched polymer and a starburst polymer, and has excellent load resistance. Since it has two or more polar groups in the molecule, it is strongly adsorbed on the solid surface and exerts its excellent lubricating effect.

In addition, this type of spherical compound includes a star
Spherical compounds such as polymers, fullerenes, and cyclophanes are also suitably used, and those having a diameter of 500 ° or less are preferable, those having a diameter of 100 ° or less, and those having a diameter of 20 ° or less are more preferably used.

A fluorine compound having one or more polar groups in a molecule is excellent in lubricity and has one or more polar groups in a molecule, so that it is strongly adsorbed on a solid surface and has an excellent lubricating effect. Demonstrate. As such a fluorine compound, a compound having a perfluoroalkyl chain or a perfluoropolyether chain is suitably used, and a compound in which only a part of the constituent carbon is hydrogenated may be used. ,
It may be unsaturated, have a branch, or be cyclic. In order to obtain the lubricity peculiar to fluorine, it is desirable that the number of carbon atoms to which fluorine is bonded is 1 or more, particularly 4 or more.

Furthermore, hydrocarbon compounds having one or more polar groups in the molecule are excellent in lubricity and, since they have one or more polar groups in the molecule, are strongly adsorbed on the solid surface and have excellent lubricating properties. It is effective. Suitable examples of such hydrocarbon compounds include stearic acid, oleic acid, linoleic acid, myristic acid, stearylamine, and oleylamine.

The polar groups of such spherical compounds, fluorine compounds and hydrocarbon compounds include amino groups, carboxyl groups, sulfonyl groups, phosphate groups, hydroxyl groups and salts thereof, or epoxy groups, isocyanate groups. And an amine base obtained by a reaction between a carboxyl group and an amino group. Suitable examples thereof include an ester group, an amide group, an ether group, a urethane group, and a urea group.

Such a spherical compound having two or more polar groups in the molecule, a fluorine compound having one or more polar groups in the molecule, or a hydrocarbon compound having one or more polar groups in the molecule. When used as a lubricating substance, the lubricating substance consisting of a mixture of, if necessary, may be used in combination with another lubricating substance, for example, a fatty acid or a metal salt thereof, an aliphatic ester, an aliphatic amide, Lubricants generally used such as aliphatic alcohols, monosulfides, paraffins, silicone compounds, aliphatic and fluoride esters, perfluoropolyethers and polytetrafluoroethylene are preferably used. Used together.

Also, phosphorus extreme pressure agents such as trioleyl phosphate, sulfur extreme pressure agents such as benzyl disulfide, halogen extreme pressure agents such as allyl bromide, and organometallic extreme pressure agents such as zinc diisobutyldithiophosphate. An extreme pressure agent or the like may be used in combination.

Such a spherical compound having two or more polar groups in the molecule, a fluorine compound having one or more polar groups in the molecule or a hydrocarbon compound having one or more polar groups in the molecule In order for a lubricating substance consisting of a mixture of the above to be present inside or on the surface of the magnetic recording medium, the lubricating substance should be mixed with a general-purpose organic solvent such as alcohol, hydrocarbon, ketone or ether or a fluorine-based substance. Dissolve in a solvent, apply or spray this solution on a magnetic layer or a protective film previously formed on a non-magnetic support, or dry,
Alternatively, conversely, the magnetic layer or the protective film is immersed in the above solution and dried.

Further, this kind of lubricating substance is used as a magnetic powder,
A magnetic paint is prepared by mixing and dispersing with a binder resin, an organic solvent and other additives, and the magnetic paint is applied to a non-magnetic support such as a polyester film by any means such as spraying or roll coating. It is also performed by a method such as coating and drying.

A solution in which this kind of lubricating substance is dissolved may be applied again to the magnetic layer thus formed by coating, spraying, dipping, etc. in the same manner as described above. Further, after the adhesion, excess lubricating substances and the like may be washed with a solvent. Alternatively, a lubricating substance may be contained on the opposite side of the magnetic layer, and the image may be transferred to the magnetic layer.

When the magnetic layer in which this kind of lubricating substance is present is a ferromagnetic metal thin film layer, a vacuum deposition, sputtering, plasma, or the like is applied on the ferromagnetic metal thin film layer.
A protective film made of carbon (diamond-like or amorphous), silicon oxide, zirconium oxide, chromium oxide, an organic compound, or the like may be provided, or a protective film containing fluorine, silicon, or the like may be provided. . further,
The surface of the ferromagnetic metal thin film layer may have a small amount of moisture attached to the surface, or may have a rust preventive such as a benzotriazole type applied thereto.

Also, the surface of the protective film or the like provided on the ferromagnetic metal thin film layer may be subjected to oxygen and ammonia plasma treatment. Active species can be deposited, and this type of lubricating substance can be more stably present without lowering the hardness of the protective film.
Further, it is also possible to stably make this kind of lubricating substance exist by performing ultraviolet irradiation treatment, heat treatment and the like. These treatments may be performed before depositing such a lubricating substance or after depositing this type of lubricating substance. May be performed after washing.

The amount of such a lubricating substance applied on the ferromagnetic metal thin film layer is 0.5 to 20 with respect to the surface of the ferromagnetic metal thin film layer.
It is preferable to be in the range of mg / m ² , and if it is less than this, it is difficult to uniformly adhere a lubricating substance to the surface of the ferromagnetic metal thin film layer, and still durability cannot be sufficiently improved. On the other hand, if the amount is too large, the magnetic head and the ferromagnetic metal thin film layer are undesirably stuck.

In the case where it is contained in the magnetic layer, 10
If the amount is less than mg / m ^{2, the} desired effect cannot be obtained.
If it is more than 0 mg / m ^2, it sticks to the magnetic head and it becomes impossible to run. Therefore, it is preferable that the amount is in the range of 10 to 100 mg / m ² .

The amount and content of this type of lubricating substance can be determined by, for example, immersing a magnetic tape coated with the lubricating substance in a solvent overnight, extracting the lubricating substance with a solvent, and then subjecting the magnetic tape to gas chromatography. Alternatively, it can be determined by liquid chromatography or the like.

In addition, a lubricating substance of this kind includes a layer composed of a spherical compound having two or more polar groups in a molecule on a magnetic layer, and a fluorine compound having one or more polar groups in a molecule. Or a lubricant layer in which a layer composed of a hydrocarbon compound having one or more polar groups in the molecule is provided. In this case, two or more polar groups And a layer composed of a fluorine compound having one or more polar groups in a molecule or a layer composed of a hydrocarbon compound having one or more polar groups in a molecule. Or a lower layer.

As described above, a layer composed of a spherical compound having two or more polar groups in the molecule, a layer composed of a fluorine compound having one or more polar groups in the molecule, or one or more polar compounds in the molecule. When a lubricant layer is formed by laminating a layer made of a hydrocarbon compound having a polar group and is present as a lubricating substance, when the magnetic layer is a ferromagnetic metal thin film layer, two or more polar groups are present in the molecule. The amount of the spherical compound having a group is preferably in the range of 0.2 to 19.8 mg / m ² , and the fluorine compound having one or more polar groups in the molecule or the one or more compounds in the molecule is preferable. It is preferable that the amount of the hydrocarbon compound having a polar group to be applied is in the range of 0.2 to 19.8 mg / m ² .

When the magnetic layer is a coating type magnetic layer containing a magnetic powder, the amount of the spherical compound having two or more polar groups in the molecule, which is laminated on the magnetic layer, is reduced. The amount is preferably in the range of 1 to 99 mg / m ² , and the amount of the fluorine compound having one or more polar groups in the molecule or the hydrocarbon compound having one or more polar groups in the molecule is preferably 1 to 99 mg / m ² . Preferably it is in the range of 99 mg / m ² .

In the case of a ferromagnetic metal thin film layer, the magnetic layer is formed of Co, Ni, Fe, Co--Ni, Co--Cr, Co
-P, Co-Ni-P, Fe-Co-B, Fe-Co-
Ni, Co-Ni-Fe-B, Fe-Ni, Fe-C
o, Co-Pt, Co-Ni-Pt or various ferromagnetic materials such as those obtained by adding oxygen to these materials by vacuum deposition, ion plating, sputtering, plating, etc., using a non-magnetic material such as a polyester film. It is formed by a method such as attaching it to one or both surfaces of a support, and is usually formed to a thickness in the range of 0.03 to 1 μm.

In the case of a coating type magnetic layer, a magnetic paint is prepared by mixing and dispersing a magnetic powder together with a binder resin, an organic solvent and other additives to prepare a magnetic paint. It is formed on the body by any method such as spraying or roll coating and drying, and is usually formed to a thickness of about 0.05 to 10 μm.

At this time, the magnetic powder used is γ
-Fe ₂ O ₃ , Fe ₃ O ₄ , γ-Fe ₂ O ₃ and Fe ₃ O
Iron oxide in the intermediate oxidation state with ₄ , Co-containing γ-Fe
Oxide-based magnetic powders such as ₂ O ₃ , Co-containing γ-Fe ₃ O ₄ , CrO ₂ , barium ferrite, Fe, Co, F
Various conventionally known magnetic powders such as metal magnetic powders such as e-Ni-Cr alloys and nitride-based magnetic powders such as iron nitride are widely used. In the case of acicular magnetic powders, average particle diameter (long axis) is used. It is preferable to use those having an average axis ratio (average long axis ratio / average short axis ratio) of usually about 0.05 to 1 μm and an average axis ratio (average short axis ratio) of about 5 to 10; .07
Those having a thickness of about 0.3 μm are preferably used.

Examples of the binder resin include vinyl chloride-vinyl acetate copolymers, cellulose resins, polyurethane resins, polyester resins, polyvinyl butyral resins, polyacryl resins, epoxy resins, and the like. As a binder resin for a magnetic recording medium, any of those generally used, such as a resin, a phenol resin, and a polyisocyanate compound, is preferably used.

Further, as the organic solvent, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone,
A solvent suitable for dissolving the binder resin to be used, such as ethyl acetate, benzene, toluene, xylene, tetrahydrofuran, dioxane, etc., is used alone or in combination of two or more without any particular limitation.

The magnetic paint may optionally contain various additives commonly used, for example, abrasives, antistatic agents, dispersants, coloring agents and the like.

In the case where the magnetic layer is formed only on one side of the non-magnetic support having the magnetic layer formed on the surface, a back coat layer may be provided on the opposite side. -A non-magnetic powder such as bon black and calcium carbonate is mixed and dispersed with a binder resin such as a vinyl chloride-vinyl acetate copolymer, a polyurethane resin, a cellulose resin, and an organic solvent to form a back coat layer. A coating composition is prepared by preparing a coating for use, applying the coating on the opposite side of the nonmagnetic support, and drying.

As the non-magnetic support, plastics such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide and polyvinyl chloride, aluminum alloys and titanium alloys are preferably used. . The non-magnetic support may be in any form such as a tape, a sheet, a disk, a card and the like, and may have a surface provided with projections.

As described above, the spherical compound having two or more polar groups in the molecule of the present invention and the fluorine compound having one or more polar groups in the molecule or one or more polar groups in the molecule are used. A lubricating substance comprising a mixture with a hydrocarbon compound having the compound can be used favorably for a magnetic recording medium. However, in addition to a lubricating substance, a resin for paint (corrosion-proof lining, non-adhesive coating, weather resistance) Paint), fiber treatment agent (water / oil repellent), release agent, oil resistant paper, leveling agent, adhesive, digestive agent, antifoam fiber (as sheath component), optical lens, medical polymer material It can be used as well.

[0040]

Next, an embodiment of the present invention will be described. Example 1 Co-Ni was obliquely incident-deposited on a 10 μm-thick polyethylene terephthalate film under an oxygen atmosphere to give a 0.055 μm-thick Co—Ni—O [Co: Ni (weight ratio) = 80]. : 20], and then cut into 8 mm width.

Next, a spherical compound having 16 amino groups on the surface [Starburst ™ (PANMAN) Den]
drimer Generation2, Aldric
h) was dissolved in a mixed solution of methyl ethyl ketone: isopropyl alcohol: pentafluoropropanol = 1: 3: 3 to a concentration of 0.05% by weight, and a carboxyl group was added to the terminal. Perfluoropolyester having
Ter [F (CF ₂ CF ₂ CF ₂ O) _n CF ₂ CF ₂ CO
OH, average molecular weight 2200, manufactured by Daikin Co .; Demnum]
Was dissolved to a concentration of 0.05% by weight, and the above-mentioned ferromagnetic metal thin film layer was immersed in this solution and dried to form a lubricant layer on the ferromagnetic metal thin film layer. Was prepared.

Example 2 In forming the lubricant layer in Example 1, the perfluoropolyether used in Example 1 was replaced with perfl.
urooctanoic acid [F (CF ₂ ) ₇
COOH, manufactured by Daikin Fine Chemical Co., Ltd.] was dissolved in a concentration of 0.05% by weight, and a lubricant layer was formed in the same manner as in Example 1 to produce a videotape.

Example 3 In forming the lubricant layer in Example 1, 3-perfluoropolyether was used instead of the perfluoropolyether used in Example 1.
fluorohexyl-1,2-epoxyprop
ane [F (CF ₂ ) ₆ CH ₂ CH (O) CH ₂ , manufactured by Daikin Fine Chemical Co.] was dissolved in a concentration of 0.05% by weight in the same manner as in Example 1 except that the lubricant layer was dissolved. Was formed to produce a videotape.

Example 4 In the formation of the lubricant layer in Example 1, the spherical compound Starbust ™ (PAMA) used in Example 1 was used.
N) Spherical compound having 16 amino groups on the surface [DS] instead of Dendrimer Generation 2
M Dendrimer DAB (PA) 16, DSM
Was manufactured in the same manner as in Example 1 except that 0.05% by weight was dissolved in a lubricant layer, and a videotape was produced.

Example 5 In forming the lubricant layer in Example 1, the spherical compound Starbust ™ (PAMA) used in Example 1 was used.
N) Instead of the Dendrimer Generation 2, a spherical compound having 32 carboxyl groups on the surface [Starburst ™ (PANAN) Dendrim
er Generation 2.5, manufactured by Aldrich] was dissolved at a concentration of 0.05% by weight, and the perfluoropolyether having a hydroxyl group at the terminal was substituted for the perfluoropolyether used in Example 1. [F
(CF ₂ CF ₂ CF ₂ O) _n CF ₂ CF ₂ CH ₂ OH,
An average molecular weight of 2200, manufactured by Daikin Co.] was dissolved to a concentration of 0.05% by weight, and a lubricant layer was formed in the same manner as in Example 1 to produce a videotape.

Example 6 In forming the lubricant layer in Example 5, 1H, 1H was used instead of the perfluoropolyether used in Example 5.
-Pentadecafluorooctylamine
e [F (CF ₂ ) ₇ CH ₂ NH ₂ , manufactured by Daikin Fine Chemical Co., Ltd.] was used to form a lubricant layer in the same manner as in Example 5 except that the concentration was 0.05% by weight.
A videotape was prepared.

Example 7 In forming the lubricant layer in Example 5, the perfluoropolyether used in Example 5 was replaced with 3-perfluoropolyether.
fluorohexyl-1,2-epoxyprop
ane [F (CF ₂ ) ₆ CH ₂ CH (O) CH ₂ , manufactured by Daikin Fine Chemical Co., Ltd.] was dissolved in a concentration of 0.05% by weight in the same manner as in Example 5, except that the lubricant layer was dissolved. Was formed to produce a videotape.

Example 8 In forming the lubricant layer in Example 1, the spherical compound Starbust ™ (PAMA) used in Example 1 was used.
N) Spherical compound having 24 hydroxyl groups on the surface [Hyp] instead of Dendrimer Generation 2
erbrunched Aliphatic Poly
ester generation3 (Macromo
recules 1995, 28, 1698-1703
A lubricant layer was formed and a videotape was prepared in the same manner as in Example 1 except that the compound was dissolved so as to have a concentration of 0.05% by weight.

Example 9 The procedure of Example 1 was repeated except that the stearic acid was dissolved to a concentration of 0.05% by weight in place of the perfluoropolyether used in Example 1. ,
A lubricant layer was formed in the same manner as in Example 1, and a video tape was formed.
Was prepared.

Examples 10 to 18 Co was evaporated obliquely on a 6 μm-thick polyethylene terephthalate film in an oxygen atmosphere to a thickness of 0.0
A ferromagnetic metal thin film layer of 55 μm Co—O is formed, and then the ferromagnetic metal thin film layer is formed by plasma polymerization using RF of 13.56 MHz, ethylene as a monomer gas, and hydrogen as a carrier gas. DLC (diamond-like carbon) with a thickness of 20 nm on the thin film layer
A protective film was formed and cut into a width of 8 mm.

Next, on the DLC protective film of the ferromagnetic metal thin film layer on which the DLC protective film was formed, in the same manner as in Examples 1 to 9, Examples 1 to 9 shown in Table 1 below were formed. A lubricant layer was formed, and video tapes of Examples 10 to 18 were produced.

Examples 19 to 27 α-Fe magnetic powder (coercive force: 1500 Oe, saturation magnetization: 100 parts by weight, 120 emu / g) Vinyl chloride-vinyl acetate-vinyl alcohol copolymer 20 ° (VAGH, manufactured by UCC) Functional isocyanate compound 5 〃 Carbon black (average particle size 0.024 μm) 3 〃 α-Al ₂ O ₃ powder 3 〃 myristate 2 シ ク ロ cyclohexanone 150 〃 toluene 130 中 で in a ball mill for 72 hours The dispersion was dispersed to prepare a magnetic paint. Next, each magnetic paint was applied to a thickness of 15 μm.
m was coated on a polyethylene terephthalate film having a thickness of 5 μm after drying, dried to form magnetic layers, calendered, and cut into 8 mm widths.

Next, the lubricant layers formed in Examples 1 to 9 shown in Table 1 below were formed on this magnetic layer in the same manner as in Examples 1 to 9, and the video tapes of Examples 19 to 27 were formed. -A sample was prepared.

[0054]

Example 28 A ferromagnetic metal thin film layer was formed on a polyethylene terephthalate film in the same manner as in Example 1 and cut to a width of 8 mm. This ferromagnetic metal thin film layer was formed with 16 amino groups on the surface. Having a spherical compound [Starburst ™ (PAMA
N) Dendrimer Generation2, A
ldrich) into isopropyl alcohol solution
It was immersed in a solution in which the concentration was 0.05% by weight and dried to form a lower layer on the ferromagnetic metal thin film layer.

Next, a part having a carboxyl group at the terminal
Fluoropolyether [F (CF ₂ CF ₂ CF ₂ O) _n C
F ₂ CF ₂ COOH, average molecular weight 2200, manufactured by Daikin Co .; Demnum] was converted to 1,1,2-trifluoro-1,2,2
The ferromagnetic metal thin film layer on which the lower layer was formed was immersed in the 2-trichloroethane solution so as to have a concentration of 0.05% by weight, and dried in this solution to form an upper layer. The laminated lubricant layer was formed to produce a video tape.

Example 29 In the formation of the lubricant layer in Example 28, Example 2 was applied.
0.05% by weight of the perfluoropolyether used in Example 8
In place of the 1,1,2-trifluoro-1,2,2-trichloroethane solution, perfluorooctanoic
Acid [F (CF ₂ ) ₇ COOH, manufactured by Daikin Fine Chemical Co., Ltd.] was used in the same manner as in Example 28 except that a 0.05% by weight solution of 1,1,2-trifluoro-1,2,2-trichloroethane was used. Then, a lubricant layer was formed to produce a video tape.

Embodiment 30 In the formation of the lubricant layer in Embodiment 28, Embodiment 2 was repeated.
0.05% by weight of the perfluoropolyether used in Example 8
Instead of a solution of 1,1,2-trifluoro-1,2,2-trichloroethane, 3-perfluorohexyl-
1,2-epoxypropane [F (CF ₂ ) ₆ C
H ₂ CH (O) CH ₂ , manufactured by Daikin Fine Chemical Co., Ltd.] 0.05% by weight of 1,1,2-trifluoro-1,2,2
Example 2 except that a 2-trichloroethane solution was used.
In the same manner as in No. 8, a lubricant layer was formed to produce a video tape.

Example 31 In the formation of the lubricant layer in Example 28, Example 2
Globular compound Starbust ™ (PAM
AN) of the Dendrimer Generation2
Instead of the 0.05% by weight isopropyl alcohol solution, a spherical compound having 16 amino groups on the surface [DSM De
ndrimer DAB (PA) 16, manufactured by DMS)
A lubricant layer was formed in the same manner as in Example 28 except that a 0.05% by weight isopropyl alcohol solution was used, and a video tape was produced.

Embodiment 32 In the formation of the lubricant layer in Embodiment 28, Embodiment 2
Globular compound Starbust ™ (PAM
AN) of the Dendrimer Generation2
Instead of a 0.05% by weight isopropyl alcohol solution, a spherical compound having 32 carboxyl groups on the surface [Sta
rbastTM (PAMAN) Dendrimer G
enhancement2.5, manufactured by Aldrich]
A 5% by weight isopropyl alcohol solution was used, and the perfluoropolyether used in Example 28 was dissolved in 0.1%.
In place of the 05% by weight 1,1,2-trifluoro-1,2,2-trichloroethane solution,
Fluoropolyether [F (CF ₂ CF ₂ CF ₂ O) _n C
F ₂ CF ₂ CH ₂ OH, average molecular weight 2200, manufactured by Daikin Co.] 0.05% by weight of 1,1,2-trifluoro-1,
A lubricant layer was formed in the same manner as in Example 28 except that a 2,2-trichloroethane solution was used, and a video tape was produced.

Example 33 In the formation of the lubricant layer in Example 32, Example 3
0.05% by weight of the perfluoropolyether used in Step 2
1H, 1H-pentadecafl instead of 1,1,2-trifluoro-1,2,2-trichloroethane solution
urooctyl amine [F (CF ₂ ) ₇ CH
₂ NH ₂ , manufactured by Daikin Fine Chemical Co., Ltd.] to form a lubricant layer in the same manner as in Example 32 except that a 0.05% by weight solution of 1,1,2-trifluoro-1,2,2-trichloroethane was used. Then, a videotape was produced.

Embodiment 34 In the formation of the lubricant layer in the embodiment 32, the embodiment 3
0.05% by weight of the perfluoropolyether used in Step 2
Instead of a solution of 1,1,2-trifluoro-1,2,2-trichloroethane, 3-perfluorohexyl-
1,2-epoxypropane [F (CF ₂ ) ₆ C
H ₂ CH (O) CH ₂ , manufactured by Daikin Fine Chemical Co., Ltd.] 0.05% by weight of 1,1,2-trifluoro-1,2,2
Example 3 except that a 2-trichloroethane solution was used.
In the same manner as in Example 2, a lubricant layer was formed to produce a video tape.

Example 35 In the formation of the lubricant layer in Example 28, Example 2
Globular compound Starbust ™ (PAM
AN) of the Dendrimer Generation2
Instead of the 0.05% by weight isopropyl alcohol solution, a spherical compound having 24 hydroxyl groups on the surface [Hyperbr
anchored Aliphatic Polystete
r generation3 (Macromolecu
Les 1995, 28, 1698-1703), a lubricant layer was formed and a videotape was prepared in the same manner as in Example 28 except that a 0.05% by weight isopropyl alcohol solution was used. Produced.

Embodiment 36 In the formation of the lubricant layer in the embodiment 28, the embodiment 2
0.05% by weight of the perfluoropolyether used in Example 8
Instead of the 1,1,2-trifluoro-1,2,2-trichloroethane solution, 0.05% by weight of stearic acid 1,1,1
A lubricant layer was formed in the same manner as in Example 28 except that a 2-trifluoro-1,2,2-trichloroethane solution was used, and a videotape was produced.

Examples 37 to 45 In the same manner as in Example 10, a ferromagnetic metal thin film layer was formed on a polyethylene terephthalate film.
A protective film was formed and cut into 8 mm widths. On this DLC protective film, the lubricant layers formed in Examples 28 to 36 shown in Table 2 below were formed in the same manner as Examples 28 to 36. Video tapes of Examples 37 to 45 were produced.

In the same manner as in Example 19, a magnetic layer was formed on a polyethylene terephthalate film and cut into a width of 8 mm. On this magnetic layer, as in Examples 28 to 36, the following Table 1 was used. Then, the lubricant layers formed in Examples 28 to 36 shown in (1) and (2) were formed, and video tapes of Examples 46 to 54 were produced.

[0067]

Comparative Example 1 A fluorinated ether compound having a hydroxyl group at one molecular end (F
OMBLIN Z DOL, manufactured by Montefluos, having an average molecular weight of 2,000) was dissolved in 1,1,2-trifluoro-1,2,2-trichloroethane at a concentration of 0.05% by weight to prepare a solution of a fluoride ether compound. did. Next, using the obtained fluorine-containing ether compound solution, in the same manner as in Example 1, a fluorine-containing ether compound was formed on the ferromagnetic metal thin film layer.
A film made of a tell compound was formed to produce a videotape.

Comparative Example 2 A fluorinated ether compound having a carboxyl group at one end of the molecule (FOMBLINZ DIAC, Monteflu)
os, 0.05% by weight to 1,1,2-trifluoro-1,2,2-trichloroethane.
By dissolving to a concentration, a solution of the fluorinated ether compound was prepared. Next, using the obtained fluoride ether compound solution, a film made of the fluoride ether compound was formed on the ferromagnetic metal thin film layer in the same manner as in Example 1 to produce a video tape. .

COMPARATIVE EXAMPLE 3 Using the fluorinated ether compound solution used in Comparative Example 1, a film made of a fluorinated ether compound was formed on the DLC protective film in the same manner as in Example 10, and -A sample was prepared.

COMPARATIVE EXAMPLE 4 Using the ether fluoride compound solution used in Comparative Example 2, a film made of the ether fluoride compound was formed on the DLC protective film in the same manner as in Example 10, and the -A sample was prepared.

Comparative Example 5 Using the ether fluoride compound solution used in Comparative Example 1, a film made of the ether fluoride compound was formed on the magnetic layer in the same manner as in Example 19, and a video tape was formed. Was prepared.

Comparative Example 6 Using the solution of the ether fluoride compound used in Comparative Example 2, a film made of the ether fluoride compound was formed on the magnetic layer in the same manner as in Example 19, and a video tape was formed. Was prepared.

The video tapes obtained in each of Examples and Comparative Examples were examined for still durability by the following method.

<Still Durability> An 8 mm VTR (EV-S90 manufactured by Sony Corporation) was used under the conditions of 20 ° C. and 50% RH using the video tape obtained in each of the examples and comparative examples.
Using 0), the still time until the reproduction output was reduced by 6 db from the initial value was measured. Tables 3 and 4 below show the results.

[0076]

[0077]

From the results shown in Tables 3 and 4, it can be seen that the spherical compound having two or more polar groups in the molecule of the present invention and the fluorine compound having one or more polar group in the molecule or one compound in the molecule of the present invention. The lubricating substance comprising a mixture with the above-mentioned hydrocarbon compound having a polar group has a still time equal to or longer than that of a conventional fluorine-based lubricating substance and a hydrocarbon-based lubricant when used in a video tape. As described above, it is understood that the video tape obtained by the present invention exhibits excellent lubricity.

[0079]

As is clear from Tables 3 and 4,
The video tape obtained according to the present invention exhibits excellent lubricity. From this, it can be seen that a spherical compound having two or more polar groups in the molecule of the present invention and one or more polar groups in the molecule A lubricating substance comprising a mixture with a fluorine compound having a or a hydrocarbon compound having one or more polar groups in the molecule has good lubricity, high speed, low speed, high load,
Despite the low load, the two solids contacting each other can be slid with low friction and low abrasion.
A lubricating substance comprising a mixture of a spherical compound having at least one polar group and a fluorine compound having at least one polar group in the molecule or a hydrocarbon compound having at least one polar group in the molecule. It can be seen that when used, a magnetic recording medium having excellent durability can be obtained.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location // C10N 20:06 40:18

Claims (13)

[Claims] 1. A compound comprising a spherical compound having two or more polar groups in a molecule and a fluorine compound having one or more polar groups in a molecule or a hydrocarbon compound having one or more polar groups in a molecule. A lubricating substance consisting of a mixture. 2. The lubricating substance according to claim 1, wherein the spherical compound is a spherical compound composed of at least one member selected from the group consisting of dendrimers, hyperbranched polymers and starburst polymers. 3. The lubricating substance according to claim 1, wherein the spherical compound is a spherical compound having a diameter of 500 ° or less. 4. The lubricating substance according to claim 1, wherein the fluorine compound is a fluorine compound having at least one kind of chain selected from the group consisting of a perfluoroalkyl chain and a perfluoropolyether chain. 5. An amine base obtained by reacting a polar group with an amino group, a carboxyl group, a sulfonyl group, a phosphoric acid group, a hydroxyl group and a salt thereof, or an epoxy group, an isocyanate group, or a carboxyl group with an amino group. Or, an ester group, an amide group, an ether group, a urethane group,
The lubricating substance according to claim 1, which is at least one or more polar groups selected from the group consisting of urea groups. 6. A magnetic recording medium in which a magnetic layer is provided on one or both sides of a non-magnetic support, wherein a spherical compound having two or more polar groups in a molecule is provided inside or on the surface of the magnetic layer; A magnetic recording medium comprising a lubricating substance comprising a mixture of a fluorine compound having one or more polar groups or a hydrocarbon compound having one or more polar groups in a molecule. 7. The magnetic layer is a ferromagnetic metal thin film layer, and a lubricating substance is provided on the ferromagnetic metal thin film layer in an amount of 0.5 to 20 mg / m 2.
7. The magnetic recording medium according to claim 6, wherein the magnetic recording medium has ^two coatings. 8. The magnetic recording medium according to claim 7, wherein the ferromagnetic metal thin film layer is a ferromagnetic metal thin film layer provided with a protective film made of carbon, silicon oxide, zirconium oxide or chromium oxide on the surface. 9. The magnetic layer is a coating type magnetic layer containing a magnetic powder, a spherical compound having two or more polar groups in a molecule inside or on the surface of the magnetic layer, and a one or more spherical compounds in a molecule. 7. A lubricating substance comprising a mixture of a fluorine compound having a polar group or a hydrocarbon compound having at least one polar group in a molecule is present in an amount of 10 to 100 mg / m ^2.
The magnetic recording medium according to the above. 10. A magnetic recording medium in which a magnetic layer is provided on one or both sides of a nonmagnetic support, a layer comprising a spherical compound having two or more polar groups in the molecule on the magnetic layer, A magnetic recording medium comprising a lubricant layer comprising a layer made of a fluorine compound having one or more polar groups or a layer made of a hydrocarbon compound having one or more polar groups in a molecule. 11. The amount of a spherical compound having two or more polar groups in a molecule of a lubricant layer provided on the ferromagnetic metal thin film layer, wherein the magnetic layer is a ferromagnetic metal thin film layer. Is 0.
² to 19.8 mg / m ² , and the amount of the fluorine compound having one or more polar groups in the molecule or the hydrocarbon compound having one or more polar groups in the molecule is 0.2 to 19.8 mg. /
The magnetic recording medium according to claim 10, wherein m ² is m ² . 12. The magnetic recording medium according to claim 11, wherein the ferromagnetic metal thin film layer is a ferromagnetic metal thin film layer provided with a protective film made of carbon, silicon oxide, zirconium oxide or chromium oxide on the surface. 13. The amount of a spherical compound having two or more polar groups in a molecule of a lubricant layer provided on the magnetic layer, wherein the magnetic layer is a coating type magnetic layer containing a magnetic powder. Is 1
In ~99mg / m ^2, claim deposition amount of the hydrocarbon compound having one or more polar groups in the fluorine compound or a molecule having one or more polar groups in the molecule is 1~99mg / m ² 11. The magnetic recording medium according to item 10.