JPH0935218A - Lubricant feeding tape for preventing seizing of magnetic head and feeding tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the seizing of a magnetic head and to suppress the reduction of output owing to the seizing. SOLUTION: The top of a filmlike nonmagnetic substrate 1 having >=3μm thickness is coated with a coating material 2 contg. a per-fluoro-polyether lubricant so as to attain >=8nm surface roughness and to regulate the ratio of F to Fe to 1.0-3.0.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supply tape and a supply tape cassette for supplying an anti-seizure lubricant to a magnetic head such as a video tape recorder (VTR) or a digital audio tape recorder (DAT).

[0002]

2. Description of the Related Art In recent years,
To meet the demand for high recording density, a magnetic coating material containing very fine magnetic particles and a resin binder is coated on a non-magnetic support,
A magnetic tape using this as a magnetic layer or a thin film magnetic tape in which a magnetic layer is formed on a polyethylene terephthalate (PET) substrate by a vacuum deposition method, a plating method or a sputtering method has been developed.

In such a magnetic tape, the smoothness of the surface of the magnetic layer is made extremely excellent in order to reduce the spacing loss and increase the density. Therefore, a substantial contact area with the magnetic head becomes large, and a burn-in phenomenon (brown stain) easily occurs, which causes a decrease in output and causes a problem in durability and the like.

Conventionally, in order to recover the output reduction such as the image sticking of the magnetic head, the image sticking magnetic head is polished with a polishing tape to bring the magnetic head close to the initial output. However, polishing such a magnetic head with a polishing tape shortens the life of the magnetic head, and has the disadvantage of shortening the actual use time of the recorder itself such as a VTR or DAT.

Further, in order to eliminate the decrease in output due to the seizure of the magnetic head, the abrasive mixed in the magnetic layer of the magnetic tape is made to have a large grain size or an increased amount. Including a large-diameter abrasive in the magnetic layer of such a magnetic tape or increasing the amount of the abrasive is to increase the abrasive force of the magnetic tape with respect to the magnetic head, and the magnetic head is scraped off. Not only the life of the magnetic tape is shortened, but also in the magnetic tape, the surface property is deteriorated and electromagnetic conversion characteristics are deteriorated.

In view of the above problems, it is an object of the present invention to prevent burn-in of a magnetic head and to eliminate the output reduction due to this burn-in.

[0007]

A lubricant supply tape for preventing seizure of a magnetic head according to the present invention has a film-shaped non-magnetic support having a thickness of 3 μm or more coated with a coating containing a perfluoropolyether lubricant. At the same time, it was applied so that the surface roughness was 8 nm or more and the F / Fe value was 1.0 to 3.0.

According to the present invention, since the perfluoropolyether type lubricant is satisfactorily supplied to the magnetic head, the seizure of the magnetic head can be suppressed and the output reduction due to the seizure can be eliminated.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a magnetic head burn preventing lubricant supply tape and a supply tape cassette according to the present invention will be described below with reference to the drawings.

Example 1 In Example 1, as shown in FIG. 1, a magnetic coating 2 containing a perfluoropolyether lubricant was internally applied to a nonmagnetic support 1 having a thickness of 6.0 μm.

As the non-magnetic support 1, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), aramid film or the like can be used.

As the perfluoropolyether type lubricant (refer to the specification of Japanese Patent Application No. 6-12911), an amine salt compound of perfluoropolyether having a carboxyl group at the terminal represented by the general formula 1 is used. It is a lubricant solution dissolved in an alcohol solvent.

[0013]

## STR1 ## ^{_{R f -COO - HN + R 1}} R 2 R 3 , or ^{_{R 1 R 2 R 3 N +}} H0 - CO-R f -COO - HN + R
₁ R ₂ R ₃ (R _f represents a perfluoropolyether group. R ₁ , R
₂ , R ₃ represent hydrogen or hydrocarbon, and at least one of them represents a long-chain hydrocarbon having 10 or more carbon atoms. )

The amine salt compound of perfluoropolyether having a carboxyl group at its terminal is easily synthesized according to the following method.

That is, it can be easily obtained by uniformly dissolving perfluoropolyether having a carboxyl group at the terminal and amine with stirring, and may be heated if necessary.

Here, R ₁ , R ₂ and R in the structural formula of amine are
₃ represents hydrogen or hydrocarbon, and at least one of them is a long-chain hydrocarbon having 10 or more carbon atoms. At least one carbon number of the alkyl chain is preferably 10 or more,
Below this, lubrication or solubility may be impaired. The hydrocarbon chain may be branched or may contain a double bond. Further, the molecular chain may contain an aromatic ring.

Perfume having a carboxyl group at this end
Structure of main chain of oropolyether (R _f) Is structural formula 2 and
And structural formula 3, but the present invention is not limited to this.

The main chain of the monofunctional perfluoropolyether is represented by the following structural formula 2.

[0019]

Embedded image F (CF ₂ CF ₂ CF ₂ O) _n CF ₃ (OCF (CF ₃ ) CF ₂ ) _m (OCF ₂ ) _l F (CF (CF ₃ ) CF ₂ O) _k, etc. The perfluoropolyether is represented by the following structural formula 3.

[0020]

Embedded image There are (OC ₂ F ₄ ) _p (OCF ₂ ) _{q and the} like, but it goes without saying that the structure is not limited to this.

Here, l, m, n, k, p and q in the chemical structural formula of the perfluoropolyether represent integers of 1 or more. The molecular weight is not particularly limited, but is preferably about 600 to 5,000. When the molecular weight is too high, the effect of the terminal group becomes small, and when it is too small, the effect of the perfluoropolyether group becomes weak.

As the magnetic paint, for example, the following ones were used.

Ferromagnetic particles 100 parts by weight Binder 20 parts by weight Abrasive 8 parts by weight Methyl ethyl ketone 150 parts by weight Toluene 80 parts by weight

The above materials were thoroughly mixed and dispersed in a sand mill, filtered and defoamed, added with 10 parts by weight of a polyisocyanate curing agent, and stirred for about 30 minutes to uniformly mix them.

The ferromagnetic particles used in this example are ferromagnetic iron oxide, Co-doped ferromagnetic iron oxide, ferromagnetic chromium dioxide,
A ferromagnetic alloy, barium ferrite, etc. can be used. As a binder for these ferromagnetic particles, conventionally known thermoplastic resins, thermosetting resins, radiation crosslinkable resins by electron beam or the like, or mixtures thereof are used.

A raw tape in which the above-mentioned magnetic paint 2 containing a perfluoropolyether type lubricant internally added to this film-shaped non-magnetic support 1 is applied is a three-dimensional roughness meter ET- manufactured by Kosaka Laboratory.
It was measured at 30 K and mirror-finished so that the surface roughness SRa was 8 nm. In this case, the surface roughness SR of this raw tape
The temperature and pressure of the mirror-finishing roller were adjusted so that a was 8 nm.

Further, in this case, the surface of the raw tape was measured by ESCA, and the internal addition amount of the perfluoropolyether type lubricant, for example, 100 weight of ferromagnetic particles, was adjusted so that the F / Fe value became 1.0. 2 parts by weight was adjusted with respect to parts.

This original tape was used as the tape width (3.
81 mm) and the tape thus slit is incorporated into the cassette 3. As shown in FIG. 3, for example, the cassette 3 has various identification holes as shown in B to F. Depending on the type of tape and the diameter of the reel hub,
The holes B to F are opened or closed for identification, and one of the holes, for example, the hole E, is used to identify the recording / reproducing tape cassette and the magnetic head burn-in prevention lubricant supply tape cassette, for example. The tape cassette for recording and reproducing is used when the tape cassette is opened, and the lubricant supply tape cassette is used when it is closed.

This example is constructed as described above, and when this lubricant supply tape cassette is used, this perfluoropolyether lubricant is supplied to the magnetic head part and the traveling system guide part, after which This recorder eg D
When the recording / reproducing magnetic tape was run on the AT, the effect of the lubricant was able to suppress the seizure of the magnetic head, and the output level did not decrease due to the seizure of the magnetic head.

Further, since this lubricant supply tape does not scrape the burn-in portion of the magnetic head, there is an advantage that the life of the recorder is not shortened.

Example 2 In Example 2, the surface of the above-mentioned raw tape was measured by ESCA in the above-mentioned Example 1, and the above-mentioned perfluoropolyether lubricant was used so that the F / Fe value was 2.0. The amount of internal addition was adjusted. Others were the same as in the first embodiment.

Also in the second embodiment, the same operational effect as in the first embodiment was obtained.

Example 3 In Example 3, the surface of the above-mentioned raw tape was measured by ESCA in the above-mentioned Example 1, and the above-mentioned perfluoropolyether lubricant was adjusted so that the F / Fe value was 3.0. The amount of internal addition was adjusted. Others were the same as in the first embodiment.

Also in the third embodiment, the same effect as that of the first embodiment can be obtained.

Example 4 In Example 4, the thickness of the non-magnetic support 1 in Example 1 was set to 3.0 μm. Others were the same as in Example 1. Also in the fourth embodiment, the same operational effect as in the first embodiment was obtained.

Example 5 Example 5 is the same as Example 1 except that the thickness of the non-magnetic support 1 was set to 3.0 μm and the surface of the above-mentioned raw tape was measured by ESCA to obtain an F / Fe value of 2 The internal addition amount of the above-mentioned perfluoropolyether lubricant was adjusted so as to be 0.0. Others were the same as in the first embodiment.

Also in the fifth embodiment, the same operational effect as in the first embodiment was obtained.

Example 6 In Example 6, the thickness of the non-magnetic support 1 in Example 1 was set to 3.0 μm, and the surface of the above-mentioned raw tape was measured by ESCA to obtain an F / Fe value of 3 The internal addition amount of the above-mentioned perfluoropolyether lubricant was adjusted so as to be 0.0. Others were the same as in the first embodiment.

The same operational effects as in Example 1 were obtained in Example 6 as well.

Example 7 In Example 7, the original tape prepared by coating the film-like non-magnetic support 1 with the above-mentioned magnetic paint 2 containing a perfluoropolyether lubricant was manufactured by Kosaka Laboratory. Three
The surface roughness SRa is 1 as measured by the dimensional roughness meter ET-30K.
It was adjusted to be 0 nm and mirror-finished. Others were the same as in Example 1.

The same operational effects as in Example 1 were obtained in Example 7 as well.

Example 8 In Example 8, the above-mentioned raw tape in Example 1 was measured with a three-dimensional roughness meter ET-30K manufactured by Kosaka Laboratory and adjusted so that the surface roughness SRa was 10 nm. The surface of the above-mentioned raw tape is measured by ESCA while mirror-finishing, and F /
The internal addition amount of the above-mentioned perfluoropolyether lubricant was adjusted so that the Fe value was 3.0. Others were the same as in the first embodiment.

Also in the eighth embodiment, the same operational effect as that of the first embodiment was obtained.

Example 9 In Example 9, as shown in FIG. 3, a magnetic layer 4 is formed by coating the above-mentioned magnetic paint on a non-magnetic support 1 having a thickness of 6.0 μm. This magnetic layer 4 is measured with a three-dimensional roughness meter ET-30K manufactured by Kosaka Laboratory, and adjusted so that the surface roughness SRa is 8 nm, so as to be mirror-finished.

Thereafter, the above-mentioned perfluoropolyether type lubricant 5 is applied on the magnetic layer 4. In this case ESC
The surface was measured with A, and this perfluoropolyether lubricant 5 was applied so that the F / Fe value was 1.0, to obtain a raw tape.

This raw tape was DAT in the same manner as in Example 1.
The magnetic tape was slit to the same width as the magnetic tape (3.81 mm) and incorporated into the cassette 3. Also in the ninth embodiment, the same operational effect as that of the first embodiment is obtained.

Example 10 Example 10 is the same as Example 9 except that the above-mentioned perfluoropolyether lubricant 5 was applied onto the magnetic layer 4 by ES.
The surface was measured by CA and applied so that the F / Fe value was 3.0. Others were the same as in Example 9.

Also in the tenth embodiment, the same effect as that of the first embodiment is obtained.

Comparative Example 1 In Comparative Example 1, the surface of the above-mentioned raw tape was measured by ESCA in Example 1, and the above-mentioned perfluoropolyether lubricant was used so that the F / Fe value became 0.5. The amount of internal addition was adjusted. Others were the same as in the first embodiment.

In Comparative Example 1, the amount of the lubricant added was small, the magnetic head burned, and the electromagnetic conversion characteristics deteriorated.

Comparative Example 2 In Comparative Example 2, the surface of the above-mentioned raw tape was measured by ESCA in Example 1, and the above-mentioned perfluoropolyether lubricant was used so that the F / Fe value was 3.5. The amount of internal addition was adjusted. Others were the same as in the first embodiment.

In Comparative Example 2, there was a problem that the amount of the lubricant added was too large and the magnetic head was clogged.

Comparative Example 3 In Comparative Example 3, the thickness of the nonmagnetic support 1 in Example 1 was set to 2.5 μm. Others were the same as in Example 1.

In Comparative Example 3, since the non-magnetic support 1 was thin, there was an inconvenience that the drum portion of the recorder was stuck and did not run.

Comparative Example 4 Comparative Example 4 was the same as Example 1 except that the thickness of the non-magnetic support 1 was 2.5 μm and the raw tape was measured with a three-dimensional roughness meter ET-30K manufactured by Kosaka Laboratory. Roughness SRa is 10
Mirroring is performed by adjusting to be nm.
The surface of the above-mentioned raw tape was measured with, and the F / Fe value was 3.0.
The internal addition amount of the above-mentioned perfluoropolyether lubricant was adjusted so that Others were the same as in Example 1.

In Comparative Example 4, as in Comparative Example 3, since the specific magnetic support 1 was thin, there was a problem that the drum portion of the recorder was stuck and did not run.

Comparative Example 5 In Comparative Example 5, a raw tape prepared by applying the above-mentioned magnetic paint with the perfluoropolyether lubricant internally added to the film-shaped non-magnetic support 1 in the above-mentioned Example 1 was manufactured by Kosaka Laboratory. Three
The surface roughness SRa is 6 when measured with a dimensional roughness meter ET-30K.
Mirroring was performed by adjusting to be nm. Others were the same as in Example 1.

In Comparative Example 5, since the surface roughness of the magnetic tape was good, the lubricant was supplied to the magnetic head more than necessary, and the magnetic head was clogged.

Comparative Example 6 In Comparative Example 6, the above-mentioned raw tape in the above-mentioned Example 1 was measured with a three-dimensional roughness meter ET-30K manufactured by Kosaka Laboratory, and the surface roughness SRa was adjusted to 6 nm. Mirror surface and measure the surface of the above-mentioned raw tape by ESCA.
The internal addition amount of the above-mentioned perfluoropolyether lubricant was adjusted so that the Fe value was 3.0. Others were the same as in the first embodiment.

In Comparative Example 6 as well as Comparative Example 5, since the surface roughness of the magnetic tape was good, there was a problem that the lubricant was supplied more than necessary and the magnetic head was clogged.

Incidentally, the above Examples 1 to 10 and Comparative Examples 1 to 1
The lubricant supply tapes of the lubricant supply tape cassette 6 of FIG. 6 are run on the recorders (DAT), respectively. This recorder is a Sony DDS-2 drive SDT-500.
0 was used. This running was performed for a fixed time, for example, about 10 seconds.

After that, the DDSs that are usually commercially available
-Run the tape. This driving mode is DD
Since S-2 can record 4 GB, 3 GB recording and 3 GB
In the long shuttle mode (Long Shuttle mode) of GB reproduction, 50 loops are used, and the measurement environment is 45 ° C, 30% R.S.
H. Was set to be disadvantageous to the burning of the magnetic head. The error rate increase at this time and the output of this recorder shall be examined. The measurement results are shown in Table 1.
In Table 1, Comparative Example 7 was run on the tape containing no lubricant, and Comparative Example 8 was a commercially available DDS.
-2 Only the tape was run.

[0063]

[Table 1]

The results shown in Table 1 are ◯ when the loop completed 50 loops without increasing the error rate, and Δ and 50 when the loop completed 50 loops with a slight increase in the error rate.
The loop completed, but the error rate increased or the electromagnetic conversion characteristics deteriorated. ▲, the output level decreased due to seizure of the magnetic head, and 50 loops completed due to clogging or sticking of the magnetic head due to this lubricant. The one that did not exist was judged as x.

From Table 1, it was found that the samples of Examples 1 to 10 completed without any increase in the error rate and no significant deterioration of the electromagnetic conversion characteristics. In Examples 4 to 6, since the non-magnetic support 1 having a thickness of 3.0 μm is used, it is Δ, but it is considered that there is no problem in practical use.

In Comparative Example 1, since the amount of the lubricant added was small, the magnetic head was burned, which deteriorated the electromagnetic conversion characteristics.

On the contrary, in Comparative Example 2, since the amount of the lubricant added was large, the magnetic head of the recorder was clogged while the magnetic tape was running in the test mode, and the running was stopped.

In Comparative Examples 3 and 4, since the thickness of the non-magnetic support 1 was as thin as 2.5 μm, the drum portion of the recorder was stuck and did not complete.

In Comparative Examples 5 and 6, since the surface roughness of the magnetic tape is good, even if the lubricant added has the same concentration, the lubricant is supplied more than necessary to the magnetic head and the like. It caused a clogging, and caused an increase in error rate. In this case, the surface roughness of the magnetic tape is expressed in order to rub the lubricant supplied more than necessary with the magnetic tape having the surface, and the amount of the lubricant supplied is controlled. .

In Comparative Examples 7 and 8, since the lubricant was not supplied, the magnetic head was burned and the error rate was increased, and the running was not completed.

From the above results, the magnetic coating material was applied to the film-like non-magnetic support 1 having a thickness of 3 μm or more so that the surface roughness SRa was 8 nm or more, and the F / Fe value was 1.0 to 10 by ESCA. The seizure of the magnetic head can be prevented by running the lubricant supply tape in which the perfluoropolyether lubricant is internally added or surface-coated so as to be 3.0.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0073]

When the lubricant supply tape cassette 3 according to the present invention is used and the lubricant supply tape is run, the perfluoropolyether type lubricant is satisfactorily supplied to the magnetic head part and the running system guide part. , Then, when the recording / reproducing magnetic tape is run on this recorder, for example, DAT,
Due to the effect of this lubricant, it is possible to suppress the image sticking of the magnetic head, and there is an advantage that the output level is not lowered due to the image sticking of the magnetic head.

Further, since this lubricant supply tape does not scrape the burn-in portion of the magnetic head, it has an advantage that the life of the recorder is not shortened.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a lubricant supply tape for preventing seizure of a magnetic head of the present invention.

FIG. 2 is a sectional view showing another embodiment of the present invention.

FIG. 3 is a rear view showing an example of a tape cassette.

[Explanation of symbols]

 1 non-magnetic support 2 magnetic paint with internal lubricant 4 magnetic layer 5 lubricant

Claims (3)

[Claims] 1. A coating material containing a perfluoropolyether lubricant is internally applied onto a film-like non-magnetic support having a thickness of 3 μm or more, and the surface roughness is 8 nm or more and the F / Fe value is 1 or less. A lubricant supply tape for preventing seizure of a magnetic head, characterized in that the tape has a thickness of 0 to 3.0. 2. A magnetic layer is deposited on a film-shaped non-magnetic support having a thickness of 3 μm or more, and a perfluoropolyether lubricant is applied on the magnetic layer, and the surface roughness is 8
A lubricant supply tape for preventing seizure of a magnetic head, which has a thickness of at least nm and an F / Fe value of 1.0 to 3.0. 3. A lubricant supply tape cassette for preventing magnetic head sticking, wherein the lubricant supply tape for preventing magnetic head sticking according to claim 1 or 2 is incorporated.