JPS61216120A - Magnetic tape having lubricant replenishing part - Google Patents

Abstract

PURPOSE:To prevent loss of a lubricant from the upper part of a ferromagnetic metallic thin film layer and to improve sufficiently the abrasion resistance and traveling stability of the title magnetic tape by providing a lubricant replenishing tape at an appropriate position of the magnetic tape and connecting a lubricant replenishing part to the appropriate position of the magnetic tape. CONSTITUTION:A lubricant replenishing part is provided to an appropriate position at the end part or the intermediate part of a magnetic tape on which a ferromagnetic metallic thin film layer is formed. In this case, the replenishing tape is arranged so that the surface of the ferromagnetic metallic thin film layer and the surface of the coated film of the lubricant replenishing tape are continuously connected and allowed to lie in the same plane. Since the lubricant replenishing part contg. a lubricant and capable of replenishing the lubricant is connected to an appropriate position at the end part or the intermediate part of the ferromagnetic metallic thin film magnetic tape by providing the lubricant replenishing tape, the lubricant is always replenished from the lubricant replenishing part to the surface of the ferromagnetic metallic thin film layer during traveling. A hydrocarbonic lubricant, etc., is exemplified as the lubricant to be used. the content of the lubricant is preferably regulated to 0.5-5wt%, based on total solid component of the coated film.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a ferromagnetic metal thin film magnetic tape having a lubricant replenishing section, and more specifically relates to a ferromagnetic metal thin film type magnetic tape having a lubricant supply section, and more specifically, Related to thin film magnetic tape.

[Conventional technology]

In general, ferromagnetic metal thin film magnetic tapes, which are made by depositing ferromagnetic metals or their alloys on a substrate by vacuum deposition, have excellent high-density recording characteristics, but have a large coefficient of friction with the magnetic head. It is easily subject to wear and damage.

For this reason, are there any linear saturated fatty acids or their metal salts on the ferromagnetic metal thin film layer of the ferromagnetic metal thin film magnetic tape? A protective layer made of rIJ lubricant is provided (Japanese Patent Publication No. 56-30609 "4) to improve wear resistance.

[Problem that the invention seeks to solve]

However, the protective layer made of lubricant provided on the ferromagnetic metal thin film layer of this type of ferromagnetic metal thin IQ type magnetic tape is formed by applying a magnetic paint onto the substrate. The lubricant is impregnated and retained in the magnetic layer like the magnetic layer that is used, and this lubricant is not replenished to the surface of the magnetic layer during running of the magnetic tape. The lubricant tends to disappear in a short period of time,
As the number of runs increases, the coefficient of friction increases, and wear becomes significant, which may impede the running of the magnetic tape.

[Means for solving problems]

This invention was made as a result of various studies in order to eliminate these drawbacks, and the present invention has been made as a result of various studies to solve these drawbacks. A lubricant replenishing tube (1) is provided by applying a lubricant-containing paint to the base, and a lubricant replenishment tube is provided at an appropriate position on the magnetic layer side at the end or middle of the magnetic tape. By providing a lubricant supply section in series, the lubricant is continuously supplied from the lubricant supply section onto the thin ferromagnetic metal layer, thereby preventing the lubricant from disappearing from the ferromagnetic metal thin film layer. In addition to successfully and sustainably reducing the coefficient of friction on the surface of the ferromagnetic metal thin film layer, a portion of the lubricant is also favorably and sustainably transferred to the magnetic hemlock 1' and guide members that are in contact with the magnetic tape.
This magnetic tape has sufficiently improved wear resistance and running stability.

In this invention, the lubricant replenishment tape attached to an appropriate position at the end or middle of the magnetic tape on which the ferromagnetic metal thin film layer is formed is thinner than the base of the magnetic tape on which the ferromagnetic metal thin film layer is formed. A coating containing a lubricant is applied onto a substrate, and the surface of the coating formed by this application is formed on the same plane as the surface of the ferromagnetic metal thin film layer,
Connect the surface of the ferromagnetic metal thin film layer and the surface of the coating film of the lubricant replenishment tape at an appropriate position on the end or middle part of the magnetic tape on which the ferromagnetic metal thin film layer is formed so that they are continuous in the same plane. "Tei" will be established. By attaching such a lubricant replenishing tape, a lubricant replenishing part that contains and can replenish lubricant is continuously provided at an appropriate position at the end or middle part of the ferromagnetic metal thin film type magnetic tape, During running, lubricant is constantly supplied to the surface of the ferromagnetic metal thin film layer from this lubricant supply section. A portion of the supplied lubricant is transferred well to the magnetic head and the guy 1' member that are in contact with the magnetic tape, and since the lubricant is continuously supplied between these contact interfaces, the coefficient of friction is reduced. The coefficient of friction is sufficiently and sustainably reduced so that the coefficient of friction does not increase even if the number of runs of the magnetic tape increases, and the abrasion resistance and running stability of the magnetic tape are sufficiently improved. In addition, the lubricant replenishment part that is connected by attaching such a lubricant replenishment tape,
It is preferable to provide a plurality of them at appropriate positions at the ends or intermediate portions of the magnetic tape, and the more they are provided, the more the effect is exhibited, and the abrasion resistance and running stability of the magnetic tape are further improved.

The lubricants used by being incorporated into the coating film of the lubricant replenishment tape that constitutes the lubricant supply section include hydrocarbon lubricants, aliphatic compounds, fluorine-based lubricants, silicone-based lubricants, etc. , all conventionally used lubricants are suitably used, and as hydrocarbon lubricants,
For example, liquid paraffin, squalane, wax, etc.11.・
1 effect lJj group 41 go 1 course “I-1・'t 'J
7 acids, 78 fatty acids such as cic acid, palmitic acid, and stearic acid, fatty acid esters such as stearic acid-n-'7'(-l), metal salts of fatty acids such as zinc stearate, mylis A, methyl alcohol, and stearyl. Suitable examples include Ill group alcohols such as alcohols.

j In addition, examples of fluorine-based lubricants include tetrafluoroethylene, hexafluoropropylene, trichlorofluoroethylene, perfluoropolyether, perfluoroalkyl polyether, etc., and examples of silicone-based lubricants include silicone oil, etc. , modified silicone oil, etc.

like this? (a) Coatings containing lubricants are prepared by mixing and dispersing these lubricants with binder components, organic solvents, and other necessary components such as fillers, and applying this coating onto a substrate. formed by drying,
A lubricant is contained in this coating. The content of the lubricant contained in such a coating film is 0.5% of the total solid content of the coating film so that the lubricant can be well supplied during running of the ferromagnetic metal thin film magnetic tape. It is preferable that the content be within the range of ~5% by weight; if it is too small, the desired effect will not be obtained, and if it is too large, clogging of the magnetic head will occur. The thickness of the coating film containing such a lubricant is preferably within the range of 1 to 7 μm by adjusting the thickness of the base; if it is too thin, the desired effect will not be obtained; In order to make the total thickness approximately equal at the joint between the magnetic tape and the magnetic tape, the thickness of the base must be made thinner, resulting in problems such as insufficient strength.

Here, the binder resin used to form this coating film includes conventional binder resins such as vinyl chloride-vinyl acetate copolymers, polyvinyl butyral resins, polyurethane resins, cellulose resins, and isocyanate-1 compounds. The binder resin used for lJL is widely used, and in addition, organic? 8 agents include methyl isobutyl ketone, methyl ethyl ketone,
Cyclohexanone, luene, ethyl acetate, tetrahydrofuran, dimethylporumami F and the like may be used alone or in combination of two or more.

In addition, as fillers to be used when necessary, non-magnetic powders that are usually added to magnetic layers, such as hengara, alumina, zirconia, silicon carbide, garnet, silicon oxide, and chromium oxide, are suitable. used as something. When this type of non-magnetic powder is used, the durability and running stability of the lubricant replenishing part itself are improved, and the lubricant is effectively and smoothly bleed out to the surface.

Materials for forming the ferromagnetic metal thin film layer include Co, Ni, and F.
e, Co-Ni alloy, Co-Cr alloy, Co-P, C
A ferromagnetic material such as o-N1-P is used, and a ferromagnetic metal thin film layer made of these ferromagnetic materials is deposited on a substrate by means such as vacuum evaporation, ion blasting, sputtering, or plating. Formed in a way.

〔Example〕

Next, embodiments of the invention will be described.

Example 1 A polyester film with a thickness of 15 μm was loaded into a vacuum evaporation apparatus, and cobalt was heated and evaporated under a vacuum of 5×10 −5 μm to form a ferromagnetic metal thin film layer of cobalt with a thickness of 1500 μm on the polyester film. was formed. Next, the following protective layer solution was applied onto this ferromagnetic metal thin film layer, dried, and then cut into a predetermined width to produce a magnetic tape.

Protective layer solution Palmitic acid 5 parts by weight n-butyl stearate 2 //KF96 (manufactured by Shin-Etsu Chemical Co., Ltd., 1 Silicone oil) Methyl ethyl ketone 1600 Meanwhile, the following composition was thoroughly mixed and dispersed in a ball mill to prepare a paint. This was prepared and applied to a polyester film with a thickness of 11 μm to a dry thickness of 5 μm, dried to form a coating film, and cut to the same width as the magnetic tape to make a lubricant replenishment tape. Ta.

2 l-mouth cellulose 35 parts by weight Nisoborane 2301 (Nippon Boliure 20 polyurethane resin manufactured by Retan Kogyo Co., Ltd.) Coronate Shikoku Nippon Polyurethane 45/trifunctional low molecular weight isocyanate compound manufactured by Gyosha) Hengara 240 Palmitic acid 5 Stearic acid -n
-Butyl 2 //KF96 (manufactured by Shin-Etsu Chemical Co., Ltd., silicon 1〃corn oil) Methyl ethyl ketone 480〃The thus obtained lubricant replenishment tape was cut into a length of 2cl11, and this was coated with the vacuum evaporation method described above. Obtained length 50m
A ferromagnetic metal thin film type magnetic tape was created by attaching splicing tape to both ends of the magnetic tape and having lubricant replenishing parts at both ends.

Example 2 In the coating composition of the lubricant replenishment tape in Example 1, the amount of palmitic acid used was changed from 5 parts by weight to 2 parts by weight, and the amount of n-butyl stearate was changed from 2 parts by weight to 1 part by weight. A lubricant replenishing tape was prepared in the same manner as in Example 1, except that the amount of KF96 used was changed from 1 part by weight to 0.5 parts by weight, and the amount of methyl ethyl ketone was changed from 480 parts by weight to 550 parts by weight. A ferromagnetic metal thin film type magnetic tape with lubricant replenishment sections at both ends was fabricated.

Comparative Example 1 A ferromagnetic metal thin film type magnetic tape was produced in the same manner as in Example 1 except that the lubricant replenishment tape was omitted from the magnetic tape (=J arrangement).

The friction coefficient of the ferromagnetic metal thin film magnetic tape obtained in each Example and Comparative Example was measured using a cyclic friction tester, and the number of times the magnetic tape was repeatedly run and the change in the friction coefficient at that time were investigated. The running properties of the tape were tested.

[Results of invention]

Figure 1 shows the results in a graph, and as is clear from this graph, the ferromagnetic metal thin film magnetic tape prepared in Comparative Example 1, even though a protective layer made of a lubricant was formed, Regardless, the friction coefficient increases by -1 as the number of repeated runs increases, but in the ferromagnetic metal thin film magnetic tapes obtained by this invention (Examples 1 and 2), the number of repeated runs increases. However, a low coefficient of friction was maintained, which indicates that the thin ferromagnetic metal molded magnetic tape having a lubricant replenishing portion obtained by the present invention has good wear resistance and excellent running properties.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the relationship between the number of repeated runs of a ferromagnetic metal thin film magnetic tape having a lubricant replenishing portion obtained according to the present invention and the friction coefficient at that time.

Claims (1)

[Claims] 1. A lubricant replenishing tape formed by applying a paint containing a lubricant to an appropriate position at the end or middle of a magnetic tape on which a magnetic layer consisting of a ferromagnetic metal thin film layer is provided. A magnetic tape having a lubricant replenishing section, characterized in that a lubricant replenishing section is provided in series at an appropriate position on the magnetic layer side of an end or an intermediate portion of the magnetic tape.