JPH08259482A - Lubricating substance and magnetic recording medium using the same - Google Patents

Abstract

PURPOSE: To obtain a lubricating substance comprising a prescribed fluorine- containing tri-block compound, slidable between two contact materials in low friction and in low wear, capable of being coated by using an organic solvent of general purpose except a fluorine-based solvent, excellent in environmental preservation, useful as a lubricant for a magnetic recording medium. CONSTITUTION: This lubricating substance comprises a tri-block compound of a fluorinated block-non-fluorinated block-fluorinated block in which the fluorinated block contains a carbon atom not bonded to a fluorine atom at the molecular end of the non-block side. This lubricating substance, for example, comprises a tri-block compound of the formula Rf-(CH2 )n -X-Rh-y-(CH2 )n -Rf' [Rf-(CH2 )n and Rf'-(CH2 )n are fluorinated blocks; n is 1-4; the number of carbons bonded to fluorine is equal to or larger than 4 and the number of the total carbons is 3-1,000; Rh is a non-fluorinated block; x and y are each an ester bond, an ether bond, an amide bond, a urethane bond or a urea bond].

Description

Detailed Description of the Invention

[0001]

The present invention relates to high speed, low speed, high load,
The present invention relates to a lubricating substance that slides two solids in contact with each other with low friction and low wear regardless of a low load, and a magnetic recording medium using the lubricating substance as a lubricant.

[0002]

2. Description of the Related Art The surface of a solid and a lubricant have been developed for the purpose of sliding the two solids in contact with each other with low friction and low wear so as to prolong the service life of equipment and devices. Especially in the field of office automation equipment, there is a strong demand for size reduction.
Precise mechanism is adopted for sliding parts year by year. In future equipment in which precision parts slide continuously or intermittently in a wide range of environments, friction and wear at the start of sliding, at the time of sliding or at the end of sliding will be reduced more than ever, and load such as motor will be reduced. Need to be lowered.

Hitherto, in a protective lubricant system, a surface layer that is hard and does not easily wear is provided at a sliding portion, and a grease is used as a lubricant.
Semi-solid or liquid lubricants in the form of oil or oil have been used. However, in precision instruments with smoothed contact areas, no matter how high speed, low speed, high load, or low load, a lubricating substance that slides between two solids with low friction and wear can still be obtained. Therefore, it is impossible to avoid the problem that the frictional force suddenly increases suddenly at the time of starting failure or sliding.

For example, in a ferromagnetic metal thin film type magnetic recording medium formed by depositing a ferromagnetic metal or an alloy thereof on a non-magnetic support by vacuum deposition or the like, a coating type magnetic recording medium is used. Compared with this, it is easy to achieve high coercive force and thin film in the magnetic layer, and while it has excellent high-density recording characteristics, it does not use a tough binder resin and the ferromagnetic metal thin film and protective film have good surface activity. However, the friction coefficient between the magnetic head and the magnetic head is large, and the magnetic head is apt to be worn or damaged, resulting in poor durability or running performance.

Therefore, for example, Japanese Patent Laid-Open No. 60-854
27, JP-A-62-236118, JP-A-2-21.
In publications such as 0615, perfluoropolyether
By using various lubricants such as telluride lubricants, fluorinated carboxylic acid type lubricants, and partially fluorinated carboxylic acid type lubricants, these lubricants are allowed to exist on the ferromagnetic metal thin film to improve durability and running. It has been proposed to improve the sex.

Further, even in a coating type magnetic recording medium in which magnetic powder is bound with a resin, the recording density has been increased, and as an excellent lubricant replacing conventional hydrocarbon type lubricants and silicon type lubricants, The use of fluorine-based lubricants as described above is desired.

[0007]

However, even with the above-mentioned fluorine-based lubricant, it cannot be said that the durability and running property of the magnetic recording medium can be improved to a high degree.
In order to include this kind of lubricant in the magnetic layer and to attach it to the surface of the magnetic layer, it is necessary to dissolve this lubricant in a fluorine-based organic solvent and perform operations such as coating, dipping and spraying. . Fluorine-based organic solvents lead to environmental damage such as destruction of the ozone layer, and there are many problems that the cost is high because the solvent is expensive.

In view of the above-mentioned circumstances, the present invention provides a high-speed, low-speed
Regardless of high load or low load, it is possible to obtain a sliding substance with low friction and low wear between two solids that are in contact with each other, and obtain an environment-friendly lubricating substance, and use this lubricating substance as a lubricant. By doing so, it is an object to obtain a magnetic recording medium with highly improved durability and runnability.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies in order to achieve the above object. As a result, when a specific triblock material is used as a fluorine-based lubricant, the lubricant is used as a general-purpose organic solvent. It is possible to perform operations such as coating, dipping and spraying, and to slide between two solids that come into contact with low friction and low wear without causing harmful effects such as environmental damage due to the use of fluorine-based organic solvents. In addition, it was found that a magnetic recording medium with highly improved durability and running property can be obtained when this is used as a lubricant for a magnetic recording medium, and the present invention has been completed. is there.

That is, the first aspect of the present invention consists of a triblock of fluorinated blocks-non-fluorinated blocks-fluorinated blocks, and the fluorinated blocks have fluorine bonded to the molecular end on the non-fluorinated block side. The present invention relates to a lubricating substance characterized by having no carbon. A second aspect of the present invention is a magnetic recording medium having a magnetic layer on one side or both sides of a non-magnetic support, wherein the lubricating substance according to the first aspect is used as a lubricant inside or on the surface of the magnetic layer. The present invention relates to a magnetic recording medium such as a magnetic tape, a magnetic disk, or the like.

[0011]

The triblock body used in the present invention has a molecular structure in which the fluorinated blocks are bound to both ends of the non-fluorinated block, and the fluorinated blocks at both ends of the molecule can be used as a general-purpose organic solvent. Hardly dissolves, but the non-fluorinated block shows high solubility in a general-purpose organic solvent, so in the general-purpose organic solvent, the non-fluorinated block becomes a spread state, and the entire molecule exhibits solubility. It is considered to be a thing. Further, in this triblock body, since the fluorine-containing block has a carbon to which fluorine is not bound at the molecular end on the non-fluorinated block side, the influence of the high electronegativity of fluorine is the above-mentioned carbon, that is, (C
It is considered that the compound is suppressed by H ₂ ) and, as a result, the hydrolysis resistance of the ester bond connecting the non-fluorinated block and the non-fluorinated block is improved, and stable performance is exhibited as a lubricating substance.

[0012] Such Toriburotsuku body, following general formula _{(1); Rf- (CH 2} ) n -x-Rh-y- (CH 2) n -Rf' ... (1) Rf: Buddha of block Residue Rh: Non-fluorinated block Rf ′: Residue of a fluorinated block, and in this formula, a fluorinated block [Rf- (CH ₂ ) _n , (CH ₂ ) _n- Rf '] The x and y connecting to the fluorine-containing block (Rh) usually consist of any one of ester bond, ether bond, amide bond, urethane bond or urea bond, and these bonds x and y are mutually bonded. The bonds may be the same or different.

In this triblock, the number of carbon atoms to which fluorine is not attached, which is located at the molecular end on the non-fluorinated block side of the fluorinated block, that is, _{n of the} (CH ₂ ) _n chain
As for the number of, in order to obtain the above-mentioned hydrolysis resistance,
It is preferably 1 to 4. Rf constituting the main chain, Rf
The ′ may have a carbon skeleton having a linear, branched or cyclic structure, and the carbon skeleton may be either saturated or unsaturated, and only a part of the constituent carbons is fluorinated. You can buy it. In order to obtain the lubricity peculiar to fluorine, the number of carbons bonded to fluorine is preferably 4 or more, particularly 6 or more. The total number of carbons with the (CH ₂ ) _n chain is Usually, it is preferably up to 1,000. In addition, Rf and Rf constituting the main chain
If necessary, a functional group such as a hydroxyl group, a carboxyl group, an amino group, a halogen, a mercapto group, a sulfonic acid group, a phosphoric acid group, or a salt thereof may be bonded to the molecular end of ′.

The non-fluorinated block (Rh) may have a linear, branched or cyclic carbon skeleton, and the carbon skeleton may be saturated or unsaturated. Not limited to the chain, it may have an element other than carbon in the main chain, for example, a polyether chain, a polyester chain, a polycarbonate chain or the like.
The number of carbons is preferably 3 or more, preferably 4 or more, more preferably 6 or more in order to improve the solubility in an organic solvent. The larger the number, the wider the selection range of the organic solvent and the concentration. It should be up to 1,000.

Such a triblock product may be one synthesized by any method. An example of an industrially effective synthetic method is, for example, a non-fluorinated compound having a hydroxyl group, a carboxyl group, an amino group, an isocyanate group, etc. at both ends of the molecule, and an isocyanate group, an amino group at one end of the molecule. , A fluorinated compound having a carboxyl group, a hydroxyl group or the like is used to cause a reaction between the two functional groups to form an ester bond, an ether bond, an amide bond,
There is a method of chemically bonding by a bond such as a urethane bond or a urea bond.

The lubricating substance of the present invention comprises one or more of the above-mentioned triblocks as an active ingredient. When using the lubricating substance, a fatty acid or a metal salt thereof may be used, if necessary. Fatty acid esters, aliphatic amides, aliphatic alcohols, monosulfides, paraffins, silicone compounds, aliphatic and fluorinated esters,
It may be used in a mixed system with other general lubricating substances such as perfluoropolyether and polytetrafluoroethylene.

The magnetic recording medium of the present invention has a magnetic layer on one side or both sides of a non-magnetic support, and a lubricating substance consisting of the triblock body having the above-mentioned constitution as a lubricant is provided inside or on the surface of this magnetic layer. It is characterized by having. Here, in order to provide the above-mentioned lubricating substance inside or on the surface of the magnetic layer, the lubricating substance is dissolved in a general-purpose organic solvent such as hydrocarbon, alcohol, ketone or ether, and the solution is It may be applied or sprayed on the magnetic layer previously formed on the magnetic support and dried, or conversely, the magnetic layer may be dipped in the above solution and dried.

When the magnetic layer is composed of a ferromagnetic metal thin film, a carbon (diamond-like or amorphous-like) film, a silicon oxide film, a chromium oxide film, or other organic compound is formed on the thin film by vacuum deposition, sputtering, plasma or the like. The protective film may be provided. In addition, a protective film containing fluorine, silicon, or the like may be provided. Further, this ferromagnetic metal thin film may have a slight amount of water attached to its surface, or may be coated with a rust preventive such as benzotriazole.

The amount of the lubricating substance deposited on the ferromagnetic metal thin film is preferably in the range of 0.5 to 20 mg / m ² with respect to the thin film surface. If it is too small, it will be difficult to attach it evenly to the thin film surface,
Still durability cannot be improved sufficiently. On the other hand, if the amount is excessive, the magnetic head and the ferromagnetic metal thin film may stick to each other, which is not preferable.

In the coating type magnetic recording medium, coating, spraying,
In addition to adhesion formation by dipping, mix a lubricant into a magnetic paint using a general-purpose organic solvent and apply it to a non-magnetic support to form a lubricant-containing magnetic coating film. May be. In addition, further coating, spraying,
It may be adhered and formed again by dipping or the like, and after the adhesion, excess lubricant or the like may be washed with a solvent. Further, a lubricant may be contained on the opposite side of the magnetic coating film and transferred to the magnetic coating film side. The content of the lubricating substance in the magnetic coating film is preferably 10 to 100 mg / m ² .

In the magnetic recording medium of the present invention, as the non-magnetic support, a plastic such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyvinyl chloride, etc., aluminum alloy, titanium. Alloys and the like are preferably used. The non-magnetic support may be in the form of tape, sheet, disk, card or the like, or may have a projection on its surface.

In a ferromagnetic metal thin film type magnetic recording medium, Co, Ni, F is formed on one surface or both surfaces of the above non-magnetic support.
e, Co-Ni, Co-Cr, Co-P, Co-Ni-
P, Fe-Co-B, Fe-Co-Ni, Co-Ni-
Fe-B, Fe-Ni, Fe-Co, Co-Pt, Co
Various ferromagnetic materials such as -Ni-Pt or those obtained by adding oxygen to these are formed into thin films by methods such as vacuum deposition, ion plating, sputtering and plating. The thickness of the ferromagnetic metal thin film thus formed is
Usually, it is good to be in the range of 0.03 to 1 μm.

In a coating type magnetic recording medium, a magnetic coating material containing magnetic powder and a binder resin is coated on one or both sides of the above non-magnetic support, and the thickness is usually 0.1 to 10 μm.
A magnetic coating film of about m is formed. The magnetic paint may optionally contain various conventionally known compounding agents such as a filler, an antistatic agent, a dispersant, and a colorant.

Magnetic powders include γ-Fe ₂ O ₃ and Fe ₃
O ₄ , iron oxide in an intermediate oxidation state between γ-Fe ₂ O ₃ and Fe ₃ O ₄ , Co-containing γ-Fe ₂ O ₃ , Co-containing γ-Fe ₃
Various conventionally known magnetic properties such as oxide magnetic powders such as O ₄ , CrO ₂ and barium ferrite, metal magnetic powders such as Fe, Co and Fe-Ni-Cr alloys, and nitride magnetic powders such as iron nitride. The powder is widely used. In the acicular magnetic powder, the average particle size (long axis) is usually about 0.2 to 1 μm, and the average axial ratio (average long axis diameter / average short axis diameter) is usually about 5 to 10. In the case of plate-like magnetic powder, the average major axis diameter is usually 0.0
It is preferably about 7 to 0.3 μm.

As the binder resin, for example, vinyl chloride-vinyl acetate copolymer, fibrin resin, polyurethane resin, polyester resin, polyvinyl butyral resin, polyacrylic resin, epoxy resin Any of those generally used as a binder resin for magnetic recording media, such as a phenol resin and a polyisocyanate compound, is preferably used.

In the magnetic recording medium of the present invention in which the magnetic layer is formed only on one side of the non-magnetic support, a back coat layer may be provided on the opposite side. This back coat layer mixes and disperses non-magnetic powder such as carbon black and calcium carbonate with a binder resin such as vinyl chloride-vinyl acetate copolymer, polyurethane resin, fiber resin and organic solvent. Then, a coating material for the back coat layer is prepared, and the coating material is applied to the opposite surface side of the nonmagnetic support and dried to form the coating material.

The lubricating substance of the present invention can be used as a lubricant in various fields in addition to the above-mentioned lubricant for magnetic recording media, and can also be used as a coating resin (anticorrosion lining, non-adhesive coating, weatherproof coating). ), Fiber treatment agent (water repellent, oil repellent treatment), release agent, oil resistant paper, leveling agent, adhesive, fire extinguishing agent, defoaming agent, optical fiber (as sheath component), optical lens, medical polymer material It can also be used for

[0028]

As described above, according to the present invention, the contact 2
It can slide between solids with low friction and wear, and can be applied, dipped and sprayed with a general-purpose organic solvent, and there is no risk of environmental damage such as the use of fluorine-based organic solvents. , Can provide environment-friendly lubricant. Further, by using this as a lubricant for a magnetic recording medium in particular, it is possible to provide a magnetic recording medium with improved durability and runnability.

[0029]

EXAMPLES Next, examples of the present invention will be described to more specifically describe. In the following, "parts" means "parts by weight".

Example 1 To a mixture of 0.5 mol of decanedicarboxylic acid having a carboxyl group at both ends of the molecule and 1 mol of 1H, 1H-perfluoro-1-octanal, 5 mmol of sulfuric acid was added,
While the produced water was separated by a Dean-Stark water separator, the reaction was carried out at 200 ° C. for 6 hours. Then, it is purified by recrystallization or distillation to obtain a triblock body 1 represented by the following structural formula: F (CF ₂ ) ₇ CH ₂ OCO (CH ₂ ) ₁₀ COOCH ₂ (CF ₂ ) ₇ F, which is lubricated. It was made a sexual substance.

Example 2 Instead of 1H, 1H-perfluoro-1-octanal,
1H, 1H, 2H, 2H-perfluoro-1-octana
The reaction was performed in the same manner as in Example 1 except that 1 mol of the solvent was used, and the following structural formula: F (CF ₂ ) ₆ CH ₂ CH ₂ OCO (CH ₂ ) ₁₀ COOCH ₂ CH ₂ (CF ₂ ) ₆ F was used. A triblock body 2 represented by the following formula was obtained, and this was used as a lubricating substance.

Example 3 Instead of 1H, 1H-perfluoro-1-octanal,
The reaction was performed in the same manner as in Example 1 except that 1 mol of 1H, 1H-perfluoro-1-dodecanal was used, and the following structural formula: F (CF ₂ ) ₁₁ CH ₂ OCO (CH ₂ ) ₁₀ A triblock body 3 represented by COOCH ₂ (CF ₂ ) ₁₁ F was obtained, which was used as a lubricating substance.

Example 4 Instead of 1H, 1H-perfluoro-1-octanal,
1H, 1H, 8H-tetradecafluoro-1-octana
A triblock represented by the following structural formula; H (CF ₂ ) ₇ CH ₂ OCO (CH ₂ ) ₁₀ COOCH ₂ (CF ₂ ) ₇ H, by reacting in the same manner as in Example 1 except that 1 mol of hydrogen was used. Body 4 was obtained and was used as the lubricating substance.

Example 5 The reaction was carried out in the same manner as in Example 1 except that 0.5 mol of 2,6,10-dodecatriene-1,12-dicarboxylic acid was used instead of decanedicarboxylic acid. A triblock body 5 represented by the structural formula: F (CF ₂ ) ₇ CH ₂ OCO (CH ₂ CH = CHCH ₂ ) ₃ COOCH ₂ (CF ₂ ) ₇ F was obtained, and this was used as a lubricating substance.

Example 6 Reaction was carried out in the same manner as in Example 1 except that 0.5 mol of 1,1,4,4-tetramethylbutane-1,4-dicarboxylic acid was used instead of decanedicarboxylic acid. , The following structural formula; F (CF ₂ ) ₇ CH ₂ OCO (CH ₃ ) ₂ CCH ₂ CH ₂ C (CH ₃ ) ₂ COOCH ₂ (CF ₂ ) ₇ F to obtain a triblock body 6 and lubricate it. It was made a sexual substance.

Example 7 The reaction was carried out in the same manner as in Example 1 except that 0.5 mol of terephthalic acid was used instead of decanedicarboxylic acid, and the following structural formula: F (CF ₂ ) ₇ CH ₂ OCOC _{6 was used.} A triblock body 7 represented by H ₄ COOCH ₂ (CF ₂ ) ₇ F was obtained, and this was used as a lubricating substance.

Example 8 0.5 mol of 1,10-decanediamine and 2H, 2H-
1.2 moles of perfluorooctanoic acid chloride,
To 1.2 mol of pyridine, 800 g of diethyl ether was added and reacted at 50 ° C. for 12 hours. After washing with an aqueous solution of sodium hydrogencarbonate and water in this order and distilling off diethyl ether, the product was purified by recrystallization or distillation, and the following structural formula: F (CF ₂ ) ₆ CH ₂ CONH (CH ₂ ) ₁₀ NHCOCH ₂ A triblock body 8 represented by (CF ₂ ) ₆ F was obtained, which was used as a lubricating substance.

Example 9 0.5 mol of 1,10-decane dibromide and 1H, 1
1 mol of H-perfluoro-1-octanal, 5 mmol of sodium hydroxide and 80 mol of dimethylsulfoxide
0 g was added, and the mixture was reacted at 200 ° C. for 6 hours. After cooling, the mixture was diluted with water to separate an organic layer, which was washed with an aqueous sodium hydrogen carbonate solution and dried with magnesium sulfate, and then the solvent was distilled off. The residue is purified by recrystallization or distillation,
A triblock body 9 represented by the following structural formula: F (CF ₂ ) ₇ CH ₂ O (CH ₂ ) ₁₀ OCH ₂ (CF ₂ ) ₇ F was obtained, and this was used as a lubricating substance.

Example 10 0.5 mol of 1,10-decane diisocyanate and 1
1 mol of H, 1H-perfluoro-1-octanal,
The reaction was carried out at 80 ° C for 6 hours. Then, it is purified by recrystallization or distillation to obtain a triblock body 10 represented by the following structural formula: F (CF ₂ ) ₇ CH ₂ OCONH (CH ₂ ) ₁₀ NHCOOCH ₂ (CF ₂ ) ₇ F, which is lubricated. It was made a sexual substance.

Example 11 0.5 mol of 1,12-dodecane dialcohol and 1H,
5 mmol of sulfuric acid was added to 1 mol of 1H-perfluoroheptanecarboxylic acid, and the produced water was separated by a Dean-Stark water separator, and the mixture was refluxed at 200 ° C. for 6 hours to be reacted. Then purified by recrystallization or distillation, the following structural _{formula: F (CF 2) 6 CH} 2 COO (CH 2) 12 0COCH 2 (CF 2) to give the Toriburotsuku 11 represented by ₆ F, lubricating it It was made a sexual substance.

Comparative Example 1 As a conventionally known fluorine-based lubricant A, a fluorinated ether compound having a carboxyl group at one end of a molecule (carboxyl-modified Galden; average molecular weight 650) was used, and this was used as a lubricating substance. did.

Comparative Example 2 As a conventionally known fluorine-based lubricant B, perfluoro-n-octanoic acid, which is a fluorine compound having a carboxyl group at one end of a molecule, was used, and this was used as a lubricating substance. .

Comparative Example 3 As a conventionally known fluorine-based lubricant C, a fluorinated ether compound having ester groups at both ends of the molecule (DEAL manufactured by Montecatini, Italy) was used and lubricated. It was made a sexual substance.

Triblock body 1 of Examples 1 to 11 above
11 to 11 and the fluorine-containing lubricants A to C of Comparative Examples 1 to 3, the solubility in general-purpose solvents was examined. As a general-purpose solvent, n-hexane is used, and a lubricating substance is added little by little to this solvent and well stirred,
Those that were dissolved by weight% or more were evaluated as ◯, and those that were less than this were evaluated as x. The results are as shown in Table 1 below.

[0045]

[Table 1]

Example 12 A Co-Ni alloy was obliquely vapor-deposited in an oxygen gas atmosphere on a polyethylene terephthalate film having a thickness of 10 μm, and a Co-N film having a thickness of 0.15 μm was formed on the film.
A ferromagnetic metal thin film made of i-O [Co: Ni (weight ratio) = 80: 20] was formed and then cut into a width of 8 mm.

Next, as the lubricant, the lubricous substance consisting of the triblock body 1 obtained in Example 1 was used.
-A lubricant solution was prepared by dissolving it in hexane to a concentration of 0.1% by weight. The above ferromagnetic metal thin film was dipped in this lubricant solution and dried to prepare a video tape having a lubricant film made of the triblock body 1 on the ferromagnetic metal thin film.

Examples 13 to 22 As a lubricant, the triblock body 2 obtained in Examples 2 to 11 was used.
Example 12 except that a lubricious substance consisting of ~ 11 was used.
In the same manner as above, the triblock body 2
A video tape having a lubricant coating consisting of 11 was prepared.

Comparative Examples 4 to 6 The fluorine-based lubricants A to C of Comparative Examples 1 to 3 were used as the lubricants, and these were 1,1,2-trifluoro-1,2,2.
-Dissolved in trichloroethane to a concentration of 0.1% by weight,
Three lubricant solutions were prepared. Example 12 except that the ferromagnetic metal thin film was immersed in this solution and dried.
In the same manner as above, the fluorine-based lubricant A
A video tape having a lubricant coating of C was prepared.

The above Examples 12 to 22 and Comparative Examples 4 to
For each of the 6 video tapes, the still durability is 2
Under 0 ° C. and 50% RH conditions, using an 8 mm VTR (EV-S900 manufactured by Sony Corporation), the reproduction output was 6 compared to the initial value.
The still time until the dB decreased was measured. The results are as shown in Table 2 below.

[0051]

[Table 2]

Example 23 Co was obliquely vapor-deposited in an oxygen gas atmosphere on a polyethylene terephthalate film having a thickness of 6 μm, and a ferromagnetic metal made of Co—O having a thickness of 0.15 μm was formed on the film. A thin film was formed. Next, RF of 13.56MHz
(Radio Frequency) using ethylene as a monomer gas and hydrogen as a carrier gas by a plasma polymerization method to form a DLC (diamond-like carbon) with a thickness of 20 nm on the ferromagnetic metal thin film.
After forming a protective film, it was cut into a width of 8 mm.

Next, as the lubricant, the lubricous substance consisting of the triblock body 1 obtained in Example 1 was used.
-A lubricant solution was prepared by dissolving it in hexane to a concentration of 0.1% by weight. A ferromagnetic metal thin film having the above DLC protective film is dipped in this lubricant solution, dried, and a video tape having a lubricant film made of the triblock body 1 on (the DLC protective film of) the ferromagnetic metal thin film. I made a cup.

Examples 24 to 33 As the lubricant, the triblock body 2 obtained in Examples 2 to 11 was used.
Except that a lubricious substance consisting of ~ 11 is used.
In the same manner as in Example 23, a video tape having a lubricant film made of triblock bodies 2 to 11 on (the DLC protective film of) the ferromagnetic metal thin film was produced.

Comparative Examples 7 to 9 As the lubricants, the fluorine-based lubricants A to C of Comparative Examples 1 to 3 were used, and these were treated with 1,1,2-trifluoro-1,2,2.
Three types of lubricant solutions were prepared by dissolving 0.1% by weight concentration in 2-trichloroethane. DLC in this solution
In the same manner as in Example 23 except that the ferromagnetic metal thin film having the protective film was dipped and dried, the fluorine-based lubricants A to C were formed on (the DLC protective film of) the ferromagnetic metal thin film. A video tape with a lubricant coating was made.

The above Examples 23 to 33 and Comparative Examples 7 to
For each of the 9 video tapes, the still durability (still time) was examined in the same manner as in the above case. The results are as shown in Table 3 below.

[0057]

[Table 3]

Example 34 100 parts of α-Fe magnetic powder (coercive force of 1,500 oersteds, saturation magnetization of 120 emu / g), vinyl chloride-vinyl acetate-vinyl alcohol copolymer (VAG manufactured by UCC)
H) Lubrication consisting of 20 parts, 5 parts of polyfunctional isocyanate compound, 3 parts of carbon black, 3 parts of α-Al ₂ O ₃ powder, 2 parts of myristic acid, and the triblock body 1 obtained in Example 1 as a lubricant. A magnetic paint was prepared by mixing and dispersing a compounding composition consisting of 2.5 parts of the organic substance, 150 parts of cyclohexanone and 130 parts of toluene in a ball mill for 72 hours.

This magnetic paint was dried on a polyethylene terephthalate film having a thickness of 15 μm and the thickness after drying was 5 μm.
m to be coated and dried to form a magnetic coating film,
After calendering, it was cut to a width of 8 mm. Next, the lubricant substance consisting of the triblock body 1 obtained in Example 1 was used as a lubricant, and this was dissolved in n-hexane to a concentration of 0.1% by weight to prepare a lubricant solution. The above magnetic coating film was dipped in a lubricant solution and dried to prepare a video tape.

Examples 35 to 44 The triblock body 2 obtained in Examples 2 to 11 was used as a lubricant to be blended in the magnetic paint and used for preparing the lubricant solution.
Example 34 except that a lubricious material consisting of ~ 11 was used.
Ten kinds of video tapes were prepared in the same manner as in.

Comparative Examples 10 to 12 The fluorine-based lubricants A to C of Comparative Examples 1 to 3 were used as the lubricants to be blended in the magnetic paint and used to prepare the lubricant solutions, and At the time of preparation, these lubricants were dissolved in 1,1,2-trifluoro-1,2,2-trichloroethane at a concentration of 0.1% by weight, and three kinds were prepared in the same manner as in Example 34. I made a video tape of.

The above Examples 34 to 44 and Comparative Example 10
For each of the video tapes Nos. 12 to 12, the still durability (still time) was examined in the same manner as in the above case. Result is,
The results are shown in Table 4 below.

[0063]

[Table 4]

As is clear from Table 1 above, the lubricating substances of Examples 1 to 11 using the triblock bodies 1 to 11 were compared with the conventional foot lubricants A to C of Comparative Examples 1 to 3. It can be seen that the solubility in general-purpose solvents is excellent. Further, as is clear from Tables 2 to 4, Examples 12 to 11 using the triblock bodies 1 to 11 as lubricants
The video tape No. 44 has a longer still time than the video tapes of Comparative Examples 4 to 12 using the conventional foot-type lubricants A to C, and is particularly a ferromagnetic metal thin film type video tape. It can be seen that the still durability is significantly improved in the video tape in which the DLC protective film is provided on the above thin film, in particular, the above thin film.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C07C 233/47 C07C 233/47 271/20 271/20 C10M 105/54 C10M 105/54 105/56 105/56 105/68 105/68 G11B 5/71 G11B 5/71 // C10N 40:02 40:18 (72) Inventor Kazushi Miyata 1-88, Tora-Tora, Ibaraki-shi, Osaka Hitachi Maxell Co., Ltd. Within

Claims (8)

[Claims] 1. A triblock of fluorinated blocks-non-fluorinated blocks-fluorinated blocks, wherein the fluorinated blocks have non-fluorine-bonded carbon at the molecular end on the non-fluorinated block side. And a lubricious substance. 2. The number of carbon atoms to which fluorine is not bound is 1 at the molecular end on the non-fluorinated block side of the fluorinated block.
4. The lubricating substance according to claim 1, wherein the number of carbon atoms bonded to fluorine is 4 or more, and the total number of carbon atoms is up to 1,000. 3. The number of carbon atoms in an unbroken block is 3
The lubricious substance according to claim 1, which is ˜1,000. 4. The lubricating substance according to claim 1, wherein the fluorinated block and the non-fluorinated block are linked by any one of an ester bond, an ether bond, an amide bond, a urethane bond and a urea bond. . 5. A magnetic recording medium having a magnetic layer on one side or both sides of a non-magnetic support, wherein the lubricating substance according to any one of claims 1 to 4 is used as a lubricant inside or on the surface of the magnetic layer. A magnetic recording medium having. 6. The magnetic layer is composed of a ferromagnetic metal thin film, and the coating amount of the lubricating substance on the surface of the thin film is 0.5 to 20 mg / m ^2.
The magnetic recording medium according to claim 5, wherein 7. The magnetic recording medium according to claim 6, wherein the surface of the ferromagnetic metal thin film has a carbon film, a silicon oxide film or a chromium oxide film. 8. The magnetic recording medium according to claim 5, wherein the magnetic layer comprises a magnetic coating film, and the content of the lubricating substance in the coating film is 10 to 100 mg / m ² .