JPH01240274A - Hybrid polishing tape - Google Patents

Abstract

PURPOSE:To perform a good finish-polishing so that a substrate develops the cushioning ability and other various performances intended for use during the time of using a polishing tape by forming the substrate by two or more types of films having different physical properties. CONSTITUTION:A substrate for a polishing tape used for polishing magnetic heads, magnetic discs, optical fiber end faces is formed by two or more types of films having different physical properties. As a result, the substrate develops the cushioning ability and other various performances (mechanical strength, dimensional stability, heat-resisting property and the like) intended for use during the time of using the polishing tape. When a work is finish-polished with the polishing tape held closely in contact with the work, an excessive pressure applied to the polishing tape can thus be absorbed by the cushioning ability of the substrate, and the work can be favorably polished and finished.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an abrasive tape used for finish polishing of magnetic heads and magnetic disks, precision finish polishing of one end face of optical fibers, precision finish polishing of molds, etc. It is.

[Conventional technology]

The surfaces of magnetic heads, magnetic disks, etc. used in precision mechanical parts and precision electronic parts can be finished to a precision surface of, for example, micron or submicron order.
In place of the whetstones that are often needed and have been used for a long time, in recent years, inorganic fine powders made of highly hard inorganic fine powders dispersed in a resin solution have been used for polishing tapes made of polyester film. An abrasive tape (for example, Japanese Patent Publication No. 44714/1983) obtained by applying a powder dispersed resin solution and drying it to form an abrasive layer is used.

[Problem to be Solved by the Invention] However, since the conventional polishing tape has poor elasticity, when the thickness of the object to be polished is extremely thin, the polishing process using the polishing tape may It is easy to be influenced by the surface condition of the support supporting the abrasive tape, and the surface condition of the non-abrasive layer surface of the abrasive tape base material of the abrasive tape. ,
The surface of the polishing layer on the polishing tape may be affected by distortions (unevenness in the coating when forming the polishing layer, rare protrusions that occur), and may also be affected by the inclusion of foreign matter, making it difficult to achieve a uniform polishing finish. It has its drawbacks.

Furthermore, with the conventional polishing tape, it is difficult to adjust the pressure when pressing the polishing tape against the surface of the object to be polished, such as a magnetic disk, so if polishing is performed under insufficient pressure, polishing will not be possible. On the other hand, when polishing is carried out under excessive pressure, there are also drawbacks such as the formation of a deep polishing layer.

Furthermore, conventional abrasive tapes do not have sufficient strength, break or tear due to slight scratches, and when stretched with force, they stretch completely and do not return to their original state. , still possesses many shortcomings.

In contrast, the present invention does not have these drawbacks, and in particular, even when the thickness of the object to be polished is extremely thin, it is not affected by the surface condition of the support supporting the object to be polished. In addition, the polishing layer may be affected by distortion of the polishing layer due to the surface condition of the support of the polishing tape, the surface condition of the polished layer surface of the polishing tape base material, and coating unevenness during polishing layer formation. Furthermore, there is no possibility of being affected by foreign matter during polishing work, and
It is easy to adjust the pressure when pressing the polishing tape against the surface of the object to be polished, and even if excessive pressure is applied to the polishing tape, it will be absorbed into the polishing tape. The present invention provides a polishing tape that can perform good polishing.

[Means for Solving the Problems] The present invention has been made in order to solve the above-described drawbacks of conventionally known abrasive tapes. To this end, we conducted extensive research on polishing tape from various aspects, including the polishing material, its particle size, adhesives, and hardening agents, but we were not successful at all in obtaining the desired polishing tape.

Therefore, the inventors of the present invention focused on a film-like base material for polishing tape, and although they made extensive studies on material selection and thickness, they were not successful. Therefore, we completely changed our thinking and used a two-layer tape base material laminated with polyurethane film instead of the conventional single-layer tape base material made only of polyester film. We unexpectedly discovered that despite being thinner, we can obtain an unprecedented and excellent base material for tapes that has excellent strength and elasticity and cannot be obtained with conventionally known single films. Obtained.

Based on this new knowledge, further studies were conducted and the present invention was completed. An important feature of the present invention is that two or more kinds of film-like base materials having different physical properties are used in combination.

In the present invention, films include, in addition to synthetic resins, paper, cellophane, metals (aluminum foil, stainless steel foil, etc.), various laminate films, processed films (FRP films, etc., films reinforced with fibers, glass fibers, wires, etc.) If the substrate is in the form of a film, all the materials can be used alone or in combination as appropriate.

In the present invention, two or more of these films having different physical properties are used in combination, and the physical properties include, for example, the following. It refers to mechanical strength, dimensional stability, heat resistance, elasticity, elongation, elongation resistance, chemical resistance, light resistance, oil resistance, moisture resistance, impact resistance, and other physical properties related to polishing films. be.

In the present invention, films having such physical properties are appropriately selected depending on the purpose and used by laminating them together. For example, by laminating a film with high mechanical strength and a film with high elasticity, Completely separate films are pasted together and used.

However, even if the material is the same, the physical properties will change if the thickness of the film changes. For example, the same material may have different physical properties, such as adding mechanical strength by laminating a thicker film on top of a highly elastic film, and such cases are also included in the present invention. be done. Furthermore, as with stretched films, the properties of polyamide, polypropylene, etc. films that have been reprocessed and uniaxially stretched differ from those that have been biaxially stretched, so such cases are not included in the present invention. Ru.

In this way, by changing the material, or by changing the thickness, reprocessing, manufacturing method, etc. of the same material, various films with different physical properties are prepared, and two or more of these films are used depending on the purpose. By using them together, it is possible to precisely meet various needs. If two or more types of single fill J having several kinds of irregular physical properties are used in combination, an even more irregular abrasive tape can be obtained.

In the present invention, these base materials are used together. That is, in the present invention, the abrasive tape according to the present invention is one in which two or more types of films having different physical properties are laminated together in the film-like abrasive tape base material of the abrasive tape. Laminated here refers to laminating two or more layers of these films,
It refers to laminating, and it refers to attaching these by appropriate means such as gluing, heat welding, pressure bonding, etc. In addition, if necessary, it can be done in spots at appropriate places, only at the edges, or by combining these, etc. A portion of the film may be adhered, or the two ends may be sandwiched without adhesion and the films may be simply overlapped.

In this way, polishing tapes that are particularly suitable for various uses can be freely manufactured. For example, polyethylene terecrate, polyacrylate, polycarbonate 1
- A film made of polyimide, etc. with a thickness of about 10 to 150 μm and having excellent properties such as mechanical strength, dimensional stability, and heat resistance, and a film made of polypropylene, polyethylene, polyurethane, etc. with a thickness of about 1 to 150 μm and elasticity. A film that combines two or more types of films with excellent properties and has properties required as a base material such as mechanical strength, dimensional stability, and heat resistance, and properties that contribute to cushioning properties such as elasticity. Suitable for use. The polishing layer may be formed on either the front or back surface of the polishing tape base material, and in order to improve the adhesion between the polishing layer and the polishing tape base material, the polishing layer and the polishing tape base material may be formed on either the front or back surface. An undercoat layer may be provided between the base material and the base material. Further, the polishing layer may be formed either before or after bonding the polishing tape substrate.

The polishing layer is formed by a conventional method.
For example, with abrasive particles such as aluminum oxide, silicon carbide, chromium oxide, iron oxide, diamond, zirconium oxide, silicon nitride, boron nitride, emery, cerium oxide, etc., the average particle size of the secondary particles is about 0.1 to 60 μm, Thickness composed of a binder resin made of one or more resins such as polyester resin, salt/vinyl acetate resin, polyurethane resin, butyral resin, polyamide resin, epoxy resin, acrylic resin, nitrified cotton, chloride rubber, etc. Sa3~1
00 μm, but in order to improve properties such as abrasion resistance, solvent resistance, heat resistance, and adhesion to the substrate in the polishing layer, an isocyanate-based curing agent is added, and the cured resin layer and I can do something.

Generally, the polishing layer contains about 100 to 1400 parts by weight of abrasive particles per 100 parts by weight of the binder component.

The method of applying the polishing layer forming coating liquid to the polishing film substrate includes two rolls and three rolls.

There are roll coats using four rolls, gravure coats, kiss coats, knife coats, pie coats, lot coats, comma coats, spray coats, hard coats, etc.; in the roll coat method and gravure coat method,
Both the direct method and reverse method can be used,
Especially two or three.

When using the four-roll reverse roll coating method, a coating layer with excellent surface smoothness can be obtained.

[Example] Hereinafter, the specific structure of the polishing tape of the present invention will be described based on manufacturing examples.

Example 1 Xylylene diisocyanate [manufactured by Moroboshi Ink ■] was added to the abrasive dispersion resin liquid [A] having the following composition.

χEL curing agent O)] is combined with the 10H group in the polyester resin in the abrasive dispersion resin [A] and the isocyanate group (-NG
O) was added in an amount corresponding to (-NGO/-〇〇) -5 (equivalent ratio), and then diluted with an equivalent mixed solvent of toluene and methyl ethyl ketone with a viscosity of 250 cp. Apply the coating solution to a 25 μm thick polyethylene terephthalate film [manufactured by Kijin.

Tetoron film] and a 20 μm thick polyurethane film [Dipura Urethane Film, manufactured by Dainippon Plastics Co., Ltd.] were laminated together to form a 50 μm thick abrasive tape base material. After drying, it was subjected to an aging treatment at 45°C for 10 days to form an abrasive layer with a thickness of 20 μm, thereby producing an abrasive tape having a buffering property [1], which is an embodiment of the present invention.
] was obtained.

Abrasive material dispersion resin liquid [A] (1) Polyester resin -=---1=40 parts by weight [
Toyobo ■: Hiron #1o3] (2) Aluminum oxide ----------------------20
0 parts by weight [Fujimi Abrasive ■knee 1110000] (
3) Toluene −−−−−−−−−−−−−−−−−
----------60 parts by weight (4) Methyl ethyl ketone---60 parts by weight Example 2 Base material for polishing tape in the manufacturing process of polishing tape [1] in Example 1 As a polyethylene terephthalate film with a thickness of 16 μm [Lumirror, manufactured by Toshi] and a thickness of 16 μm
μm polyethylene terephthalate film [manufactured by Toshi,
Example 1 of the present invention was prepared in the same manner as in Example 1, except that a base material with a thickness of 50 μm was used, in which polyethyleneimine was applied as an undercoat layer on each side of the Lumirror and then polyethylene was sand-laminated. A tape (ii) having cloth-like cushioning properties was obtained.

Comparative Example 1 Everything was the same as in Example 1 except that a 50 μm thick polyethylene terephthalate film (manufactured by Kijin Co., Ltd., Tetron) was used as the polishing tape base material in the manufacturing process of polishing tape [1] in Example 1. An abrasive tape (iii) was prepared and used for comparison.

A 3.5-inch floppy disk (manufactured by Nippon Memorex ■) with a center line average roughness of 0.045 μm was heated at 400 rpm while feeding each polishing tape at a speed of 5 mm/sec. Polishing the surface of the floppy disk by rotating the floppy disk, and measuring the center line average roughness (μm) of the polished surface of the obtained floppy disk and the occurrence of streak-like scratches on the polished surface of the floppy disk. The table shows the number of defective products.

As is clear from the above results, according to the present invention, almost no defective products were produced, and it can be seen that the effects of the present invention are outstanding.

[Function and effect of the invention]

In the polishing tape of the present invention, the film-like polishing tape base material on which the polishing layer is formed is composed of two or more types of films having different physical properties,
When the abrasive tape is used, the abrasive tape base material of the abrasive tape exhibits various desired properties such as cushioning properties.

Therefore, the tape according to the present invention not only can finely adapt to the shape, structure, material, and other properties of the object to be polished, but also has durability, abrasion resistance, mechanical strength, and tensile resistance. It is possible to give desired properties such as gender, and it is extremely slender.

For example, the abrasive tape according to the present invention, which is particularly provided with cushioning properties, can be used even when the object to be polished is extremely thin.
It is not affected by the surface condition of the support that supports the object to be polished, and is not affected by the surface condition of the abrasive tape support or the surface condition of the non-abrasive layer of the abrasive tape base material. The polishing layer is not affected by distortions caused by coating unevenness during polishing layer formation, and furthermore, it is not affected by foreign matter mixed in during polishing work, and the object to be polished is It is easy to adjust the pressure when pressing the abrasive tape against the surface of the abrasive tape, and even if an overvoltage force is applied to the abrasive tape, it will be absorbed into the abrasive tape, resulting in extremely good results. Polishing can be performed.

Claims (1)

[Claims] An abrasive tape comprising an abrasive layer on a film-like abrasive tape base material, wherein the film-like abrasive tape base material is composed of two or more types of films having different physical properties. .