JPH08267364A - Abrasive tape - Google Patents

Abstract

PURPOSE: To obtain an abrasive tape capable of polishing ceramic and the like of high hardness well and producing with low cost. CONSTITUTION: An abrasive tape is composed of an abrasive layer 20 and a support body 10, wherein the former 20 comprising abrasive fine powder and a binder 21 is disposed on the latter 10. For the abrasive fine powder, diamond particles 22 and an abrasive particles with a Moh's hardness of 9 or more are used in a weight ratioof 50:50 to 10:90.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing tape, and is particularly suitable for polishing and cleaning ceramic ceramic heads of magnetic recording / reproducing devices, and for polishing, cleaning, polishing, varnishing, and texture of various ceramics. The present invention relates to a polishing tape.

[0002]

2. Description of the Related Art Conventionally, a polishing tape having a polishing layer composed of fine abrasive powder and a binder on a non-magnetic support for polishing or cleaning a magnetic head of a magnetic recording / reproducing apparatus has been used. Widely used. In addition, this type of polishing tape is also widely used for so-called texture treatment, etc., in which fine "streaks" are formed on the surface of a hard disk substrate to prevent head adsorption when the disk is used.

By the way, since ceramics and related products have high hardness, they are subjected to the above-mentioned polishing, cleaning, texture, and further polishing, varnishing, etc. (These are all types of polishing in a broad sense. Unless otherwise specified, "polishing" refers to polishing in this broad sense)
It is conceivable to use a polishing tape containing diamond particles in the fine abrasive powder. Japanese Patent Laid-Open No. 5-309571 discloses that
An example of such an abrasive tape is shown. The polishing tape shown here contains a fine abrasive powder containing a first granular abrasive, a second granular abrasive, and diamond particles. Further, Japanese Patent Application Laid-Open No. 62-130168 discloses a polishing tape containing fine abrasive powder containing diamond particles and another granular abrasive.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The polishing tape disclosed in Japanese Patent No. 571 is certainly effective for ceramics having high hardness, but on the other hand,
Since the fine abrasive powder contains three types of fine powders, there are problems that the cost is high and the polishing is easy and the polishing ability is low.

Further, Japanese Patent Application Laid-Open No. 62-130168 does not mention at all what proportion of diamond particles and another granular abrasive should be contained to obtain a good polishing effect.

[0006] Therefore, an object of the present invention is to provide a polishing tape which can satisfactorily polish a ceramic having a high hardness and can be formed at a relatively low cost.

[0007]

A first polishing tape according to the present invention is a polishing tape having a polishing layer comprising fine abrasive powder and a binder on a support as described in claim 1. , Abrasive fine powder, weight ratio 50:50 ~ 10:
It is characterized by comprising 90 diamonds and an abrasive having a Mohs hardness of 9 or more.

According to a second aspect of the present invention, the second abrasive tape is characterized in that the abrasive having a Mohs hardness of 9 or more is alumina.

According to a third polishing tape of the present invention, in the above second polishing tape, the average particle diameter of diamond is 10 μm or less and the average particle diameter of alumina is 0.1 to 8 μm. It is characterized by being in the range. The average particle diameter of diamond and alumina is preferably within 3 times, more preferably within 2 times that of the other. That is, if this difference in average particle diameter is large, one of diamond and alumina will enter between the other and the polishing effect will be impaired.

A fourth polishing tape according to the present invention is the polishing tape of the first, second or third aspect as set forth in claim 4, wherein the support is a polyester having a thickness in the range of 4 to 300 μm. It is characterized by being.

The weight ratio of diamond to alumina is preferably 50:50 to 20:80, more preferably 40:60 to 20:80. That is, considering the average particle diameter, the maximum particle distribution, and the thickness, it was found that diamond should be contained in an amount of 20 to 40% by weight in order to maintain the original function.

More specifically, as the alumina, α-alumina, γ-alumina and fused alumina having an average particle diameter within the above range can be used. On the other hand, as the diamond, natural or artificial (synthetic) diamond having an average particle diameter within the above range can be used.

More specifically, as the diamond powder that can be used in the present invention, for example, among the diamond powders of "Diamond Micron Powder 300 Series" and "Diamond Micron Powder Standard Series" of General Electric Company, average Particle diameter is "0-1 / 10 µm", "0-1
/ 4 μm ”,“ 0 to 1/2 μm ”,“ 0 to 1 μm ”,
"0 to 2 µm", "1/4 to 1/2 µm", "1/4 to
1 μm ”,“ 1/2 to 1 μm ”,“ 1/2 to 2 μm ”,
"1 / 2-3 µm", "3 / 4-1 µm", "1-2 µm"
m ”,“ 1 to 3 μm ”,“ 1 to 5 μm ”,“ 2 to 3 μm ”
m ”,“ 2-4 μm ”,“ 2-5 μm ”,“ 2-6 μm ”
m ”,“ 3-6 μm ”,“ 4-6 μm ”,“ 4-8 μm ”
m ”,“ 5 to 10 μm ”, and“ 6 to 10 μm ”. The average particle diameter of diamond is preferably 8μ
m or less, and more preferably 6 μm or less.

Further, the polishing layer should appropriately contain carbon black such as rubber furnace, rubber thermal, color black, and acetylene black for the purpose of preventing electrification of the tape, shading, adjusting friction coefficient, and improving durability. You can Specific examples of the abbreviations of these carbon blacks in the United States are SAF, ISAF, IISAF, T, H.
AF, SPF, FF, FFF, HMF, GPF, AP
F, SRF, MPF, ECF, SCF, CF, FT, M
There are T, HCC, HCF, MCF, LFF, RCF, etc., and those classified into American ASTM standard D-1765-82a can be used. The average particle diameter of these carbon blacks used in the present invention is 5 to 1000 n.
m (by electron microscope observation), nitrogen adsorption method specific surface area is 1
~ 800 m ² / g, pH 4-11 (JIS standard K-6221-
1982 method), dibutyl phthalate (DBP) oil absorption is 10 ~
It is 800 ml / 100 g (JIS standard K-6221-1982 method). In the present invention, carbon black having a particle size of 5 to 100 nm is used for the purpose of lowering the surface electric resistance of the coating film for the polishing layer.
In addition, when controlling the strength of the coating film for the polishing layer, a particle size of 50-1000
nm carbon black is preferably used. Also, in order to control the surface roughness of the polishing layer coating film, smoothing is performed to reduce spacing loss, and finer carbon black (particle size less than 100 nm) is roughened to reduce the friction coefficient. Coarse-grained carbon black (particle size 10
0 nm or more) is preferably used.

As described above, the kind and the amount of carbon black added are properly selected according to the purpose required for the polishing tape. Further, these carbon blacks may be used after being surface-treated with a dispersant described below or grafted with a resin. Further, a carbon black produced by treating the furnace at a temperature of 2000 ° C. or higher at a temperature of 2000 ° C. or more and partially graphitizing the surface can also be used. Furthermore, hollow carbon black can be used as the special carbon black. These carbon blacks are the inorganic powders in the polishing layer.
It is desirable to use 0.1 to 10 parts by weight with respect to 0 parts by weight.

When carbon black is contained in the back layer, it is preferably used in an amount of 20 to 400 parts by weight based on 100 parts by weight of the resin described later. The carbon black that can be used in the present invention can be referred to, for example, “Carbon Black Handbook” (edited by Carbon Black Association, published in 1972).

As the binder used in the polishing layer, conventionally known thermoplastic resins, thermosetting resins, reactive resins, electron beam curable resins, ultraviolet curable resins, visible light curable resins and mixtures thereof. Can be used.

The thermoplastic resin has a softening temperature of 150 ° C. or lower, an average molecular weight of 10,000 to 300,000, and a degree of polymerization of about 50 to 2000, more preferably 200 to 700.
For example, vinyl chloride vinyl acetate copolymer, vinyl chloride copolymer, vinyl chloride vinyl acetate vinyl alcohol copolymer, vinyl chloride vinyl alcohol copolymer,
Vinyl chloride vinylidene chloride copolymer, vinyl chloride acrylonitrile copolymer, acrylic ester acrylonitrile copolymer, acrylic ester vinylidene chloride copolymer, acrylic ester styrene copolymer, methacrylic ester acrylonitrile copolymer, methacrylic acid Ester vinylidene chloride copolymer, methacrylic acid ester styrene copolymer, urethane elastomer, nylon-silicone resin, nitrocellulose-polyamide resin, polyfucca vinyl, vinylidene chloride acrylonitrile copolymer, butadiene acrylonitrile copolymer, polyamide resin, Polyvinyl butyral, cellulose derivative (cellulose acetate butyrate, cellulose diacetate, cellulose triacetate, cellulose propionate, nit Cellulose, ethyl cellulose,
(Methyl cellulose, propyl cellulose, methyl ethyl cellulose, carboxymethyl cellulose, acetyl cellulose, etc.), styrene-butadiene copolymer, polyester resin, polycarbonate resin, chlorovinyl ether acrylate copolymer, amino acid resin, various synthetic rubber thermoplastic resins and A mixture of these is used.

Further, the thermosetting resin or reactive resin has a molecular weight of 200,000 or less in the state of a coating liquid, and by heating and humidifying after coating and drying, the molecular weight is infinite due to reactions such as condensation and addition. The following are preferably used. Further, among these resins, those not softened or melted before the resin is thermally decomposed are particularly preferable. Specifically, for example, phenol resin, phenoxy resin, epoxy resin, polyurethane resin, polyester resin, polyurethane polycarbonate resin, urea resin, melamine resin, alkyd resin, silicone resin, acrylic reaction resin (electron beam curing resin), epoxy-polyamide Resin, nitrocellulose melamine resin, mixture of high molecular weight polyester resin and isocyanate prepolymer, mixture of methacrylate copolymer and diisocyanate prepolymer, mixture of polyester polyol and polyisocyanate, urea formaldehyde resin, low molecular weight glycol / high molecular weight Mixtures of diol / triphenylmethane triisocyanate, polyamine resins, polyimine resins and mixtures thereof.

These thermoplastic, thermosetting resins and reactive resins contain carboxylic acid (C) as a functional group in addition to the main functional group.
OOM), sulfinic acid, sulfenic acid, sulfonic acid (SO ₃ M), phosphoric acid (PO (OM) (OM)), phosphonic acid, sulfuric acid (OSO ₃ M), and acidic groups such as ester groups (M is H, alkali metal, alkaline earth metal, hydrocarbon group), amino acids; aminosulfonic acids,
Sulfuric acid or phosphoric acid esters of amino alcohols, sulfobetaine, phosphobetaine, amphoteric groups such as alkylbetaine type, amino group, imino group, imide group, amide group, etc., and also hydroxyl group, alkoxyl group, thiol group, alkylthio group, Halogen groups (F, Cl, Br, I), silyl groups, siloxane groups, epoxy groups, isocyanato groups, cyano groups, nitrile groups, oxo groups, acryl groups, phosphine groups are usually contained in one type or more and 6 types or less. The functional group preferably contains 1 × 10 ⁻⁶ to 1 × 10 ⁻² eq per 1 g of the resin.

In the present invention, the above binders are used alone or in combination, and other additives are appropriately added to the polishing layer. The mixing ratio of the polishing agent and the binder in the polishing layer is 5 to 70 parts by weight of the binder with respect to 100 parts by weight of the polishing agent in total. The mixing ratio of the fine powder and binder in the back layer is 8 to 400 parts by weight of binder with respect to 100 parts by weight of fine powder. As the additive, a dispersant, a lubricant, an antistatic agent, an antioxidant, a fungicide, a coloring agent, a solvent and the like are appropriately added.

In the present invention, the polyisocyanate used as a curing agent in the polishing layer is tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, naphthylene-1,5-diisocyanate, o-toluidine. Isocyanates such as diisocyanate, isophorone diisocyanate, triphenylmethane triisocyanate and isophorone diisocyanate, products of the isocyanates with polyalcohols, and condensation products of the isocyanates 2
It is possible to use a 10-mer polyisocyanate, or a product of polyisocyanate and polyurethane in which the terminal functional group is isocyanate. The average molecular weight of these polyisocyanates is preferably 100 to 20000.

Commercially available trade names of these polyisocyanates are Coronate L, Coronate HL, Coronate 2030, Coronate 2031, Millionate MR, Millionate MTL (manufactured by Nippon Polyurethane Co.), Takenate D-102, Takenate D-110 N. , Takenate D-20
0, Takenate D-202, Takenate 300 S, Takenate 500 (manufactured by Takeda Pharmaceutical Co., Ltd.), Sumidule T-80, Sumidule 44S, Sumidule PF, Sumidule L, Sumidule N, Death Module L, Death Module IL,
Death module N, death module HL, death module T65, death module 15, death module R, death module RF, death module SL, death module Z
4273 (manufactured by Sumitomo Bayer Co., Ltd.) and the like, and these can be used alone or in combination of two or more by utilizing the difference in curing reactivity.

For the purpose of accelerating the curing reaction, hydroxyl groups (butanediol, hexanediol, molecular weight of 1000 to
It is also possible to jointly use 10000 polyurethane, water, etc.), a compound having an amino group (monomethylamine, dimethylamine, trimethylamine, etc.), a metal oxide catalyst and a catalyst such as iron acetylacetonate. It is desirable that these compounds having a hydroxyl group or an amino group are polyfunctional. These polyisocyanates are preferably used in an amount of 2 to 70 parts by weight, and more preferably 5 to 50 parts by weight, based on 100 parts by weight of the total amount of the binder resin and the polyisocyanate.

The powdery lubricant used in the polishing layer includes graphite, molybdenum disulfide, boron nitride, graphite fluoride, calcium carbonate, barium sulfate, silicon oxide, titanium oxide, zinc oxide, tin oxide and disulfide. Inorganic fine powder such as tungsten, acrylic styrene resin fine powder, benzoguanamine resin fine powder, melamine resin fine powder, polyolefin resin fine powder, polyester resin fine powder, polyamide resin fine powder, polyimide resin fine powder, Resin fine powders such as poly-fucca ethylene-based resin fine powder and the like can be mentioned.

As the organic compound type lubricant, silicone oil (dialkyl polysiloxane, dialkoxy polysiloxane, phenyl polysiloxane, fluoroalkyl polysiloxane (KF96, KF69 manufactured by Shin-Etsu Chemical Co., Ltd.)),
Fatty acid-modified silicone oil, fluoroalcohol, polyolefin (polyethylene wax, polypropylene, etc.), polyglycol (ethylene glycol, polyethylene oxide wax, etc.), tetrafluoroethylene oxide wax, polytetrafluoroglycol, perfluoroalkyl ether, perfluorofatty acid, perfluoro Compounds with fluorine or silicon introduced such as fatty acid ester, perfluoroalkyl sulfuric acid ester, perfluoroalkyl sulfonic acid ester, perfluoroalkylbenzene sulfonic acid ester, perfluoroalkyl phosphoric acid ester, alkyl sulfuric acid ester, alkyl sulfonic acid ester, alkyl phosphonic acid Triester, alkylphosphonic acid monoester, alkylphosphonic acid diester, alkylphosphoric acid ester Le, organic acids and organic acid ester compounds such as succinic acid ester, triazaindolizine,
Heterocyclic ring compounds containing nitrogen and sulfur such as tetraazaindene, benzotriazole, benzotriazine, benzodiazole and EDTA, monobasic fatty acids having 10 to 40 carbon atoms and monohydric alcohols having 2 to 40 carbon atoms Or dihydric alcohol, trihydric alcohol, tetrahydric alcohol,
Fatty acid esters consisting of any one or more of hexavalent alcohols, monobasic fatty acids having 10 or more carbon atoms and monohydric acids having 11 to 70 carbon atoms in total with the carbon number of the fatty acid Fatty acid esters composed of hexavalent alcohols, fatty acids or fatty acid amides having 8 to 40 carbon atoms, fatty acid alkylamides, and aliphatic alcohols can also be used.

Specific examples of these compounds include butyl caprylate, octyl caprylate, ethyl laurate, butyl laurate, octyl laurate, ethyl myristate, butyl myristate, octyl myristate, 2-ethylhexyl myristate, Ethyl palmitate, butyl palmitate, octyl palmitate, 2-ethylhexyl palmitate, ethyl stearate, butyl stearate, isobutyl stearate, octyl stearate, 2-ethylhexyl stearate, amyl stearate, isoamyl stearate, 2 stearate.
Ethyl pentyl, 2-hexyldecyl stearate, isotridecyl stearate, stearic acid amide, stearic acid alkylamide, butoxyethyl stearate,
Anhydrosorbitan monostearate, anhydrosorbitan distearate, anhydrosorbitan tristearate, anhydrosorbitan tetrastearate, oleyl oleate, oleyl alcohol, lauryl alcohol, montan wax, carnauba wax, etc. Or in combination.

In the present invention, a so-called lubricating oil additive can be used alone or in combination as a lubricant. As such a lubricating oil additive, an antioxidant (known as a rust preventive agent) ( Alkylphenol, benzotriazine, tetraazaindene, sulfamide, guanidine, nucleic acid, pyridine, amine, hydroquinone, ED
Metal chelating agents such as TA), rust suppressants (naphthenic acid, alkenyl succinic acid, phosphoric acid, dilauryl phosphate, etc.), oiliness agents (rapeseed oil, lauryl alcohol, etc.), extreme pressure agents (dibenzyl sulfide, tricre) Examples thereof include zirconium phosphate, tributyl phosphite, etc.), detergent dispersants, viscosity index improvers, pour point depressants, foam depressants and the like.
These lubricants range from 0.01 to 100 parts by weight of binder.
It is added in the range of 30 parts by weight.

Regarding these, IBM Technica Bulletin (IBM Technica
l Disclosure Bulletin) Vol.9, No.7, p779 (12 December 1966)
Mon), Electronic (ELEKTRONIK) 1961 No.12, p3
80, Applied Chemistry Handbook pp954-967, 1980 Maruzen Co., Ltd.
Reference can be made to the compounds shown in publications and the like.

The dispersant and dispersion aid used in the present invention include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid and stearol. 2-40 carbon atoms such as acids, behenic acid, maleic acid, phthalic acid, etc.
Fatty acid (R1 COOH; R1 is an alkyl group having 1 to 39 carbon atoms, a phenyl group, an aralkyl group), an alkali metal of said fatty acid (Li, Na, K, NH 4 + , etc.) or alkaline earth metals (Mg, Ca , Ba, etc.), metal soaps (copper oleate) composed of Cu, Pb, etc., fatty acid amides; lecithin (soybean oil lecithin), etc. are used. In addition to these, higher alcohols having 4 to 40 carbon atoms (butanol, octyl alcohol, myristyl alcohol, stearic alcohol) and their sulfates, sulfonic acids, phenylsulfonic acids, alkylsulfonic acids, sulfonic acid esters, phosphoric acid monoesters, phosphoric acid Diesters, phosphoric acid triesters, alkylphosphonic acids, phenylphosphonic acids, amine compounds and the like can also be used. Further, polyethylene glycol, polyethylene oxide, sulfosuccinic acid, sulfosuccinic acid metal salt, sulfosuccinic acid ester and the like can also be used. These dispersants are usually used in one or more kinds, and one kind of the dispersant is 0.005 to 100 parts by weight of the binder.
It is added in the range of 20 parts by weight. These dispersants may be applied to the surface of the abrasive in advance, or may be added during the dispersion.

The antifungal agent used in the present invention is 2- (4-
Thiazolyl) -benzimidazole, N- (fluorodichloromethylthio) -phthalimide, 10,10'-oxybisphenoxarcin, 2,4,5,6 tetrachloroisophthalonitrile, P-tolyldiiodomethylsulfone, triiodo Allyl alcohol, dihydroacetate,
Mercury phenyloleate, Bis (tributyltin) oxide,
For example, salcyl anilide. Such materials are shown, for example, in "Microbial Hazard and Prevention Technology", 1972 Engineering Book, "Chemistry and Industry", Vol. 32, p. 904 (1979).

As the antistatic agent other than carbon black used in the present invention, graphite, modified graphite, carbon black graft polymer, tin oxide antimony oxide, tin oxide, titanium oxide-tin oxide-antimony oxide,
Conductive powders such as; saponin and other natural surfactants; alkylene oxide-based, glycerin-based, glycidol-based, polyhydric alcohols, polyhydric alcohol esters, nonionic surfactants such as alkylphenol EO adducts; higher alkylamines, cyclics Amine, hydantoin derivative, amidoamine, ester amide, quaternary ammonium salt, pyridine and other heterocycles, cation surfactant such as phosphonium or sulfonium; carboxylic acid, sulfonic acid, phosphonic acid, phosphoric acid, sulfuric ester group, phosphon Anionic surfactants containing acidic groups such as acid ester and phosphoric acid ester groups; amino acids; aminosulfonic acids, sulfuric acid or phosphoric acid esters of amino alcohols, amphoteric surfactants such as alkyl betaine type, and the like are used.

Some examples of these surfactant compounds that can be used as the antistatic agent are described in "Synthesis of Surfactants and Their Applications" by Ryohei Oda et al. (Maki Shoten 1972 edition); W. Baili, "Surface Active Agents" (InterScience Publications Corporation 19
1985 version); P. Sisley "Encyclopedia of Surface Active Agents, 2nd"
Volume "(Chemical Publishing Company, 1964 edition);" Surfactant Handbook ", 6th edition (Sangyo Tosho Co., Ltd.,
December 20, 1964); Hideo Marumoshi, "Antistatic Agent," written in Koshobo (1968).

These surfactants may be added alone or as a mixture. The preferred amount of these surfactants used in the abrasive layer is 100 parts by weight of the total abrasive.
It is 0.01 to 10 parts by weight. The amount used in the back layer is 0.01 to 30 parts by weight per 100 parts by weight of the binder. Although these are used as antistatic agents, they are sometimes used for other purposes such as dispersion, improvement of lubricity, and as a coating aid, a wetting agent, a curing accelerator, or a dispersion accelerator. There is also.

The organic solvent used in the present invention for dispersing, kneading and coating the abrasive particles, the binder resin and the like can be mixed and used in an arbitrary ratio. Specific examples are shown below. Ketone compounds such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isophorone;
Methanol, ethanol, propanol, butanol,
Alcohols such as isobutyl alcohol, isopropyl alcohol, and methylcyclohexanol; methyl acetate,
Ester type such as ethyl acetate, butyl acetate, isobutyl acetate, isopropyl acetate, ethyl lactate, glycol acetate monoethyl ether; ether type such as diethyl ether, tetrahydrofuran, glycol dimethyl ether, glycol monoethyl ether, dioxane; benzene,
Tar-based (aromatic hydrocarbons) such as toluene, xylene, cresol, chlorobenzene and styrene; chlorinated hydrocarbons such as methylene chloride, ethylene chloride, carbon tetrachloride, chloroform, ethylene chlorohydrin and dichlorobenzene, N, N-dimethylformaldehyde, hexane, etc. can be used.

These solvents are usually used in an arbitrary ratio of 2
Used in seeds and above. In addition, a trace amount of impurities (polymer of the solvent itself, water, raw material components, etc.) may be contained in an amount of 1% by weight or less. These solvents are used in an amount of 100 to 2000 with respect to 100 parts by weight of the total solid content of the coating liquid for the polishing layer, the back liquid and the undercoat liquid.
Used in 0 parts by weight. The preferred solid content of the coating solution is 1
~ 40% by weight. The preferred solid content of the back liquid is 1 to 20% by weight. An aqueous solvent (water, alcohol, acetone, etc.) can be used instead of the organic solvent.

The polishing layer is formed by dissolving any combination of the above-mentioned compositions and the like in an organic solvent, applying it as a coating solution on a support, drying it, and orienting it if necessary. The thickness of the support is 3 to 500 μm, preferably 4 to 300 μm. The Young's modulus in either the longitudinal direction or the width direction of the support is preferably 200 kg / mm ² or more. The material of the support, polyethylene terephthalate, polyesters such as polyethylene naphthalate, polyolefins such as polypropylene, cellulose triacetate, cellulose derivatives such as cellulose diacetate,
In addition to vinyl resins such as polyvinyl chloride, plastics such as polycarbonate, polyimide, polyamide, polysulfone, polyphenyl sulfone and polybenzoxazole, metals such as aluminum and copper and ceramics such as glass can be used. Of these, polyethylene naphthalate or polyamide is particularly preferable.

These supports may be subjected to corona discharge treatment, plasma treatment, undercoating treatment, heat treatment, dust removal treatment, metal vapor deposition treatment and alkali treatment prior to coating with the coating solution. With respect to these supports, for example, West German Patent No. 3338854A, JP-A-59-116926, and JP-A-
61-129731, U.S. Pat. No. 4,388,368; Yukio Mitsuishi, "Fiber and Industry," Vol. 31, pp. 50-55, 1975. The center line average surface roughness (Ra) of these supports is 0.001 to 1.5 μm (cutoff value 0.25 mm).
Is preferred.

The method of dispersion and kneading is not particularly limited, and the addition order of each component (resin, powder, lubricant, solvent, etc.), addition position during dispersion / kneading, dispersion temperature (0 to 80 ° C.), etc. Can be set appropriately. Ordinary kneading machine for the preparation of the polishing layer coating and the back layer coating, for example, two roll mill, three roll mill, ball mill, pebble mill, tron mill,
Sand grinder, Szegvari, Attritor, High speed impeller disperser, High speed stone mill, High speed impact mill, Disper, Kneader, High speed mixer, Ribbon blender, Cokneader, Intensive mixer,
A tumbler, a blender, a disperser, a homogenizer, a single screw extruder, a twin screw extruder, an ultrasonic disperser, etc. can be used.

Usually, a plurality of these dispersing / kneading machines are used for dispersing / kneading, and the treatment is continuously carried out. For details of the technique regarding kneading and dispersion, see T.W. C. PATH (T.C.
Patton) "Paint Flow and Pigment Dispersion"
(Paint Flow and Pigment Dispersion) Published by John Wiley & Sons in 1964 and Shinichi Tanaka "Industrial Materials"
25, 37 (1977), and in the references cited in these books. As an auxiliary means for dispersing and kneading,
In order to efficiently carry out kneading, the equivalent spherical diameter is φ0.05 mm to φ
It is also possible to use 10 cm steel balls, steel beads, ceramic beads, glass beads, organic polymer beads. Further, these materials are not limited to the spherical shape. In addition, regarding those, U.S. Patent Nos. 2,581,414 and
It is also described in the specifications such as 2,855,156. Also in the present invention, the polishing layer coating material and the back layer coating material can be prepared by kneading and dispersing according to the method described in the above-mentioned book or the cited document of the book.

As a method for applying the above-mentioned coating liquid for the polishing layer onto the support, the viscosity of the coating liquid is adjusted to 1 to 20000 centistokes (25 ° C.), and then an air doctor coater, a blade coater or an air knife coater is used. , Squeeze coater, impregnation coater, reverse roll coater, transfer roll coater, gravure coater, kiss coater, cast coater, spray coater, rod coater, forward rotation roll coater, curtain coater, extrusion coater, bar coater, lip coater, etc. can be used, Other methods can also be used, and detailed explanations of these can be found in "Coating Engineering" published by Asakura Shoten.
(Published 46.20.46) Shown in detail on pages 253 to 277. The order of applying these coating liquids can be arbitrarily selected, and corona discharge treatment or the like may be performed prior to the application of the desired liquid to improve the adhesion with the undercoat layer or the support.

When it is desired to form the polishing layer or the back layer in multiple layers, simultaneous multilayer coating or sequential multilayer coating may be performed. These coating methods are described in, for example, JP-A-57-12353.
No. 2, JP-B-62-37451, JP-A-59-142741 and JP-A-59-165239.

By the above method, about 1 is formed on the support.
The polishing layer coating liquid applied to a thickness of -100 μm or the like is immediately subjected to a multi-step drying treatment at 20 to 130 ° C., and then the formed polishing layer is dried to a thickness of 0.1 to 10 μm. At this time, the support is usually transported at a transport speed of 10 to 900 m / min, the drying temperature is controlled to 20 to 130 ° C. in a plurality of drying zones, and the residual solvent amount of the coating film is 0.1 to 40 mg / min. m ² If necessary, a back layer may be provided by the same procedure, and then the surface is smoothed to obtain a center line average surface roughness of the polishing layer or the back layer of 0.001 to 0.3 μm (cutoff 0.25 mm). Cut it into a shape,
The polishing tape of the present invention is manufactured.

In this case, powder pretreatment / surface treatment, kneading / dispersion, coating / orientation / drying, smoothing treatment, heat treatment, EB
It is desirable to continuously carry out the treatment, surface cleaning treatment, cutting and winding steps. After cutting the polishing tape thus created, it is wound on a plastic or metal reel. Immediately before or before winding, the polishing layer of the polishing tape, the back layer, the edge surface,
It is desirable to burnish and / or clean the base surface.

In order to control the surface roughness and polishing power of the polishing tape, the varnish is specifically formed by a hard member such as a sapphire blade, a razor blade, a cemented carbide blade, a diamond blade, or a ceramic blade. The projections of are shaved off to make them uniform or smooth. The Mohs hardness of these members is preferably 8 or more, but there is no particular limitation as long as the protrusions can be removed. Moreover, the shape of these members does not need to be a blade, but a square shape,
A shape such as a round shape or a wheel (these materials may be provided around a rotating cylindrical shape) can also be used.

The cleaning of the polishing tape is carried out for the purpose of removing dirt on the surface of the polishing tape and excess lubricant, that is, the surface layer of the polishing tape, that is, the polishing layer surface, the back layer surface, the edge end surface,
This is done by wiping the back side base surface with a non-woven fabric or the like. As a material for such wiping,
For example, you can use various types of Vilene made in Japan Vileen, Toraysee made in Toray, Exaine, Kimwipe, etc.,
Further, nylon non-woven fabric, polyester non-woven fabric, rayon non-woven fabric, acrylonitrile non-woven fabric, mixed-spun non-woven fabric, tissue paper and the like can be used.

Abrasives and non-magnetic powders, binders, additives (lubricants, dispersants, antistatic agents, surface treatment agents, carbon black, abrasives, light-shielding agents, used in the present invention,
Antioxidants, antifungal agents, etc., solvents and supports (undercoat layer,
A back layer, a back undercoat layer may be provided) or a manufacturing method thereof can be referred to a manufacturing method of a magnetic recording medium described in JP-B-56-26890.

[0048]

The operation and effect of the invention The polishing tape according to the present invention is
The fine abrasive powder consists of two types, diamond and an abrasive having a Mohs hardness of 9 or more, and the amount of expensive diamond added is controlled so that it does not exceed the amount of another abrasive, so It can be formed at low cost.

Since another abrasive having a Mohs hardness of 9 or more is used as another abrasive to be added together with diamond, a grinding force which is almost the same as that when all the fine abrasive powder is diamond is secured. .

When the weight ratio of diamond to the abrasive having a Mohs hardness of 9 or more exceeds 50:50, the grinding force and scratches of the grinding object are prevented in comparison with the case where the fine abrasive powder is all diamond. There are no good points. On the other hand, if the weight ratio of diamond to the abrasive having a Mohs hardness of 9 or more is less than 20:80, the grinding force is extremely poor. Therefore, this weight ratio is 50:50 to 1 as described above.
A good grinding force is secured by setting it in the range of 0:90.

The thickness of the support is 4 μm as described above.
If it is set to m or more, even if it is used for polishing ceramics having high hardness, the support is prevented from being damaged during grinding.
On the other hand, if the support has a thickness of 300 μm or less, it is easy to handle, and it is possible to avoid the problem that the rigidity is too strong and smooth and uniform polishing becomes difficult.

[0052]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The components, ratios and operation sequences shown here are
It is easily understood by those skilled in the art that modifications can be made without departing from the spirit of the present invention, and thus the present invention is not limited to the following examples. In addition, "part" in an Example shows a weight part.

(Examples 1 to 3) On a polyethylene terephthalate (PET) support having a thickness of 25 μm, an undercoat layer made of a polyester resin was applied to a thickness of 0.1 μm, and polishing coating prepared by the following composition was applied thereon. After the liquid is dried, the thickness is 6μ
Bar coat is applied so as to obtain m, and
And the samples as Comparative Examples 2, 3, 4, and 5 were prepared. The respective samples differ from each other only in the weight parts X and Y described below, and the numerical values are shown in Table 1.

Coating liquid composition Abrasive (diamond, average particle size 2 μm or less, Mohs hardness 10) X part Abrasive (alumina, average particle size 2 μm, Mohs hardness 9) Y part Binder (polyester, sodium sulfonate 2 × 10 ^-3 equivalent / g inclusion, Mw70000) 10 parts Binder (polyisocyanate, trimethylolpropane (1 mol) TDI (3 mol) adduct) 2 parts Carbon (Vulcan XC72) 5 parts Lubricant (oleic acid / olein) Oleyl acid) 0.1 part Diluent (methyl ethyl ketone / cyclohexanone = 2/1) 200 parts Diluent (toluene / MIBK) 150 parts And the polishing tape for each sample is 12.65 m wide.
processed into m. The structure of the polishing tape according to the present invention is schematically shown in FIG. As shown in the figure, this polishing tape comprises a support 10 and a polishing layer 20 formed on the support 10.
20 is a diamond particle in a binder 21
And alumina particles 23 are dispersed.

Table 1 shows the results of polishing the surface of the sintered alumina ceramic with each of the polishing tapes of Examples 1 to 3 and Comparative Examples 2 to 5 described above. Comparative Example 1 shows a ceramic which was not polished at all.

Further, (Comparison of costs) in Table 1 is shown as a relative value in which the cost of Comparative Example 5, that is, the cost of the polishing tape in which the polishing layer does not contain diamond and only alumina is used as the polishing agent is "1". There is. Further, the other evaluation items in Table 1 were obtained as follows.

(Surface Roughness) The center line average surface roughness (Ra) of the ceramic surface was measured using Surfcom manufactured by Tokyo Seimitsu Co., Ltd.
Was measured. The cutoff is 0.08 mm.

(Scratch) The surface was observed with an optical microscope at a magnification of 100 times to observe the occurrence of scratches.

(Abrasion amount of steel ball) A steel ball having a diameter of 20 mm was reciprocated 10 times on the polishing tape, and the abrasion amount was obtained from the abrasion surface of the steel ball scraped off.

[0060]

[Table 1]

As can be seen from Table 1, the polishing tapes (Examples 1 to 3) according to the present invention in which the weight ratio of diamond to alumina was 50:50 or less and 10:90 or more, the fine abrasive powder was all diamond. Grinding force and scratch generation prevention effect that are almost the same as those of the tape (Comparative Example 2) are obtained, while the costs thereof are obviously lower than those of the polishing tape in which the fine abrasive powder is all diamond. Has become.

(Examples 4 to 8) In order to determine an appropriate amount of the binder to be added, an undercoat layer made of a polyester resin was applied to a thickness of 0.1 μm on a polyethylene terephthalate (PET) support having a thickness of 50 μm. A polishing coating solution prepared with the following composition was applied thereon by bar coating so as to have a thickness of 6 μm after drying to prepare samples as Examples 4, 5, 6, 7, and 8. The respective samples differ from each other only in the weight part Z described below, and the numerical values are shown in Table 2.

Composition of coating liquid Abrasive (diamond, average particle size 2 μm or less, Mohs hardness 10) 20 parts Abrasive agent (alumina, average particle size 2 μm, Mohs hardness 9) 80 parts Binder (polyester, sodium sulfonate 2 × 10 ^-3 eq / g inclusion, Mw70000) Z part Binder (polyisocyanate, trimethylolpropane (1 mol) TDI (3 mol) adduct 2 parts Carbon (Vulcan XC72) 5 parts Lubricant (oleic acid / oleic acid) Oleyl) 0.1 part Diluent (methyl ethyl ketone / cyclohexanone = 2/1) 200 parts Diluent (toluene / MIBK) 150 parts And the polishing tape of each sample is 12.65 m wide.
processed into m. Table 2 shows the results of polishing the surface of the sintered alumina ceramic with each of the polishing tapes of Examples 4 to 8 described above. The evaluation items in Table 2 were obtained in the same manner as described above.

[0064]

[Table 2]

As can be seen from Table 2, it is desirable to add the binder in an amount of approximately 5 to 30% by weight based on the abrasive.

[Brief description of drawings]

FIG. 1 is a schematic view showing the structure of an abrasive tape according to the present invention.

[Explanation of Codes] 10 Support 20 Abrasive Layer 21 Binder 22 Diamond Particles 23 Alumina Particles

Claims (4)

[Claims] 1. A polishing tape comprising a support and a polishing layer comprising fine abrasive powder and a binder, wherein the fine abrasive powder comprises diamond in a weight ratio of 50:50 to 10:90 and mohs. A polishing tape comprising an abrasive having a hardness of 9 or more. 2. The polishing tape according to claim 1, wherein the abrasive having a Mohs hardness of 9 or more is alumina. 3. The polishing tape according to claim 2, wherein the average particle diameter of diamond is 10 μm or less and the average particle diameter of alumina is in the range of 0.1 to 8 μm. 4. The support is polyester having a thickness in the range of 4-300 μm.
Item 3. The polishing tape according to any one of items 1 to 3.