JPS63818A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS63818A JPS63818A JP14410686A JP14410686A JPS63818A JP S63818 A JPS63818 A JP S63818A JP 14410686 A JP14410686 A JP 14410686A JP 14410686 A JP14410686 A JP 14410686A JP S63818 A JPS63818 A JP S63818A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- magnetic
- solid powder
- recording medium
- magnetic recording
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000843 powder Substances 0.000 claims abstract description 94
- 239000007787 solid Substances 0.000 claims abstract description 63
- 239000002245 particle Substances 0.000 claims abstract description 58
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 36
- 239000011230 binding agent Substances 0.000 claims abstract description 9
- 239000011247 coating layer Substances 0.000 claims abstract description 7
- 239000000758 substrate Substances 0.000 claims description 3
- 239000006247 magnetic powder Substances 0.000 abstract description 22
- 239000010410 layer Substances 0.000 abstract description 12
- 239000000314 lubricant Substances 0.000 abstract description 9
- 229920005989 resin Polymers 0.000 abstract description 8
- 239000011347 resin Substances 0.000 abstract description 8
- 239000003795 chemical substances by application Substances 0.000 abstract description 4
- 125000000524 functional group Chemical group 0.000 abstract description 4
- 238000005498 polishing Methods 0.000 abstract description 3
- 238000013329 compounding Methods 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 20
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 13
- 230000002209 hydrophobic effect Effects 0.000 description 13
- 239000011248 coating agent Substances 0.000 description 12
- 238000000576 coating method Methods 0.000 description 12
- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical compound [Ba]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O AJCDFVKYMIUXCR-UHFFFAOYSA-N 0.000 description 12
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 9
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 9
- 150000001875 compounds Chemical class 0.000 description 9
- 230000005415 magnetization Effects 0.000 description 9
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 8
- 239000003973 paint Substances 0.000 description 8
- NGHMEZWZOZEZOH-UHFFFAOYSA-N silicic acid;hydrate Chemical compound O.O[Si](O)(O)O NGHMEZWZOZEZOH-UHFFFAOYSA-N 0.000 description 7
- 238000004438 BET method Methods 0.000 description 6
- 229910052742 iron Inorganic materials 0.000 description 6
- 239000000377 silicon dioxide Substances 0.000 description 6
- -1 abrasive Substances 0.000 description 5
- 239000007864 aqueous solution Substances 0.000 description 5
- 150000002433 hydrophilic molecules Chemical class 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 4
- 239000001569 carbon dioxide Substances 0.000 description 4
- 229910002092 carbon dioxide Inorganic materials 0.000 description 4
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 4
- 229910052598 goethite Inorganic materials 0.000 description 4
- AEIXRCIKZIZYPM-UHFFFAOYSA-M hydroxy(oxo)iron Chemical compound [O][Fe]O AEIXRCIKZIZYPM-UHFFFAOYSA-M 0.000 description 4
- 239000003960 organic solvent Substances 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 239000003082 abrasive agent Substances 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 229920006267 polyester film Polymers 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 2
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 229910052595 hematite Inorganic materials 0.000 description 2
- 239000011019 hematite Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 2
- 239000012948 isocyanate Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229920002635 polyurethane Polymers 0.000 description 2
- 239000004814 polyurethane Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000004094 surface-active agent Substances 0.000 description 2
- POWFTOSLLWLEBN-UHFFFAOYSA-N tetrasodium;silicate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-][Si]([O-])([O-])[O-] POWFTOSLLWLEBN-UHFFFAOYSA-N 0.000 description 2
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 2
- 239000011787 zinc oxide Substances 0.000 description 2
- TWJNQYPJQDRXPH-UHFFFAOYSA-N 2-cyanobenzohydrazide Chemical compound NNC(=O)C1=CC=CC=C1C#N TWJNQYPJQDRXPH-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 229910021555 Chromium Chloride Inorganic materials 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- TUNFSRHWOTWDNC-UHFFFAOYSA-N Myristic acid Natural products CCCCCCCCCCCCCC(O)=O TUNFSRHWOTWDNC-UHFFFAOYSA-N 0.000 description 1
- 235000021360 Myristic acid Nutrition 0.000 description 1
- 229910005091 Si3N Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- 229910052770 Uranium Inorganic materials 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 229920002433 Vinyl chloride-vinyl acetate copolymer Polymers 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 1
- 239000002216 antistatic agent Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 239000012461 cellulose resin Substances 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- QSWDMMVNRMROPK-UHFFFAOYSA-K chromium(3+) trichloride Chemical compound [Cl-].[Cl-].[Cl-].[Cr+3] QSWDMMVNRMROPK-UHFFFAOYSA-K 0.000 description 1
- 229910000428 cobalt oxide Inorganic materials 0.000 description 1
- 229910000361 cobalt sulfate Inorganic materials 0.000 description 1
- 229940044175 cobalt sulfate Drugs 0.000 description 1
- KTVIXTQDYHMGHF-UHFFFAOYSA-L cobalt(2+) sulfate Chemical compound [Co+2].[O-]S([O-])(=O)=O KTVIXTQDYHMGHF-UHFFFAOYSA-L 0.000 description 1
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(ii) oxide Chemical compound [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- BERDEBHAJNAUOM-UHFFFAOYSA-N copper(I) oxide Inorganic materials [Cu]O[Cu] BERDEBHAJNAUOM-UHFFFAOYSA-N 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- KRFJLUBVMFXRPN-UHFFFAOYSA-N cuprous oxide Chemical compound [O-2].[Cu+].[Cu+] KRFJLUBVMFXRPN-UHFFFAOYSA-N 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 150000004677 hydrates Chemical class 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 1
- 229910000480 nickel oxide Inorganic materials 0.000 description 1
- KBJMLQFLOWQJNF-UHFFFAOYSA-N nickel(ii) nitrate Chemical compound [Ni+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O KBJMLQFLOWQJNF-UHFFFAOYSA-N 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 description 1
- 229920002037 poly(vinyl butyral) polymer Polymers 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 150000003377 silicon compounds Chemical class 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000000080 wetting agent Substances 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
- 235000005074 zinc chloride Nutrition 0.000 description 1
- 239000011592 zinc chloride Substances 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は磁気記録媒体に関し、さらに詳しくは磁性層
、下塗層あるいはバンクコート層などの塗布層中に含ま
れる固形粉末の分散性、充填性および配向性が良好で電
磁気的特性などに優れた磁気記録媒体に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to magnetic recording media, and more particularly to dispersibility and filling of solid powder contained in coating layers such as magnetic layers, undercoat layers, and bank coat layers. The present invention relates to a magnetic recording medium that has good properties, orientation, and electromagnetic properties.
磁気記録媒体は、通常、磁性粉末その他の研り荊、潤滑
剤などの固形粉末、結合剤成分、有機溶剤およびその他
の非固形成分などからなる磁性塗料、下塗層用塗料、バ
ンクコート要用塗料などをポリエステルフィルムなどの
基体上に塗布、乾燥してつくられ、電磁気的特性および
耐久性に優れたものが要求される。Magnetic recording media usually require a magnetic coating consisting of magnetic powder or other abrasive powder, solid powder such as a lubricant, a binder component, an organic solvent, and other non-solid components, a coating for an undercoat layer, and a bank coat. It is made by applying paint or the like onto a substrate such as polyester film and drying it, and is required to have excellent electromagnetic properties and durability.
そのため、これら塗布層中に含まれる磁性粉末および研
暦剤、’ｔＱ？’に剤などの固形粉末は、分散性、充填
性等に優れ、磁気記録媒体に優れた電磁気的特性および
耐久性を付与できるものが好ましく、これらの固形粉末
の分散性、充填性等を改善するため、たとえば、これら
磁性粉末、研磐剤、潤滑剤などの固形粉末の粒子表面に
親水性化合物を被着するか、または疎水性化合物を被着
するなどして適当量の水酸基を存在させ、結合剤樹脂の
官能基との間で強固な結合を起こさせて、これら固形粉
末の分散性、充填性等を高めることが行われている。Therefore, the magnetic powder and abrasive agent contained in these coating layers, 'tQ? It is preferable that the solid powder such as the agent has excellent dispersibility and filling properties, and can impart excellent electromagnetic properties and durability to the magnetic recording medium, and improves the dispersibility and filling properties of these solid powders. To do this, for example, a suitable amount of hydroxyl groups can be made to exist by depositing a hydrophilic compound or a hydrophobic compound on the particle surface of solid powder such as magnetic powder, abrasive, or lubricant. The dispersibility, filling properties, etc. of these solid powders are improved by forming strong bonds with the functional groups of the binder resin.
〔発明が解決しようとする問題点］
ところが、平均粒子径が０．５μｒｎを越える従来−般
に使用される磁性粉末、研麿剤、潤滑剤等の固形粉末を
用いる場合は、粉末粒子表面の水酸基濃度を高くするほ
ど、分散性、充裟性等が向上され、水酸基濃度が高すぎ
て、かえってこれら固形粉末の分散性、充填性等に支障
をきたすということもないが、塗布層の表面平滑性を良
好にし、電磁気的特性をより良好にするため、微細な固
形粉末を使用し、この微粉末粒子表面の水酸基濃度を、
従来−般に使用される平均粒子径が０．５μｍを越える
固形粉末と同等にすると、微細な固形粉末粒子表面に存
在する水酸基の単位体績あたりの濃度が高くなりすぎて
、かえってこれら固形粉末の分散性、充填性等が低下す
る。そしてこの傾向はこれら固形粉末を微粒子化するほ
ど顕著で、平均粒子径が０．５μｍ以下の微粒子になる
と、これら固形粉末の分散性、充填性さらに配向性等に
支障が生じ、これを使用して得られる磁気記録媒体は、
電磁気的特性がむしろ低下し、耐久性も低下するという
難点がある。[Problems to be solved by the invention] However, when using conventionally and commonly used solid powders such as magnetic powders, polishing agents, and lubricants with an average particle size exceeding 0.5 μrn, the surface of the powder particles The higher the hydroxyl group concentration, the better the dispersibility, filling properties, etc., and the hydroxyl group concentration will not be too high, which will actually impede the dispersibility, filling properties, etc. of these solid powders. In order to improve smoothness and improve electromagnetic properties, fine solid powder is used, and the hydroxyl group concentration on the surface of this fine powder particle is
Conventionally, if the average particle size exceeds 0.5 μm and is equivalent to that of conventionally used solid powders, the concentration per unit of hydroxyl groups present on the surface of fine solid powder particles will become too high, and these solid powders will The dispersibility, filling properties, etc. of This tendency becomes more pronounced as these solid powders become finer particles, and when the average particle size becomes finer particles of 0.5 μm or less, problems occur in the dispersibility, filling properties, and orientation of these solid powders, making it difficult to use them. The magnetic recording medium obtained by
There are disadvantages in that the electromagnetic properties are rather deteriorated and the durability is also reduced.
〔問題点を解決するための手段〕
この発明はかかる問題点を解消するため種々検討を行っ
た結果なされたもので、塗布層中に含有させる磁性粉末
および研屏剤、潤滑剤等の全固形粉末の平均粒子径を０
．５μｍ以下とし、かつこれら固形粉末全体の粒子表面
の水酸基の濃度を６．ＯＸ Ｉ Ｑ １９〜１．２Ｘ
１０２１個／ｇの範囲内にすることによって、微細な固
形粉末の分散性、充填性および配向性を充分に向上させ
、磁気記録媒体の電磁気的特性および耐久性を充分に向
上させたものである。[Means for Solving the Problems] This invention was made as a result of various studies to solve the problems, and the present invention was made as a result of various studies to solve the problems. The average particle size of the powder is set to 0.
．． 5 μm or less, and the concentration of hydroxyl groups on the particle surface of the entire solid powder is 6. OXIQ 19~1.2X
By keeping the number within the range of 1021 pieces/g, the dispersibility, filling property, and orientation of the fine solid powder are sufficiently improved, and the electromagnetic properties and durability of the magnetic recording medium are sufficiently improved. .
この発明において使用される磁性粉末、研あ剤、潤滑剤
などの固形粉末は、固形粉末全体の平均粒子径が０．５
μｍ以下で、かつ固形粉末全体の粒子表面の水酸基の濃
度が６．Ｏｘ １０１９〜１．２ Ｘ １０２１ｆ［Ｉ
／ｇの範囲内にあるものであることが好ましく、固形粉
末全体の平均粒子径が０．５μｍより大きいものでは、
これらを例えば磁性層中に含有するような磁気記録媒体
においてはノイズを充分に小さくしたりすることができ
ず、また表面平滑性を充分に平滑にすることができない
。また、固形粉末全体の粒子表面の水酸基の濃度が６．
０Ｘ１０１９１１１ｉ１／ ｇより低すぎると、結合剤
樹脂の官能基と充分に強固に結合させることができず、
反対に１．２ｘ １０２１ｉ１ｉ１／ ｇより高すぎる
と、多すぎる水酸基が磁性粉末、研暦剤、潤滑剤などの
固形粉末の分散性、充填性および配向性に好ましくない
作用を及ぼし、いずれの場合も所期の効果を充分に発揮
することができない。従って、塗布層中に含有させる固
形粉末は、全固形粉末の平均粒子径が０．５μｍ以下で
、かつ固形粉末全体の粒子表面の水酸基の濃度が（、Ｑ
×Ｉ Ｑ １９〜１．２Ｘ １０２１ ｆ固／ｇの範囲
内にあるものであることが好ましく、全固形粉末の平均
粒子径はさらに０．４μｍ以下とし、０．３μｍ以下に
するのがより好ましい。また、固形粉末全体の粒子表面
の水酸基の濃度はさらに７．５ｘ ｌ ０１９〜１．０
Ｘ １０”？面／ｇの範囲内とし、７．５ｘ １０”
〜５．Ｏｘ １０”ｔ［Ｈ／ｇ）範囲内にするのがよ
り好ましい。このように塗布層中に含有させる磁性粉末
、研潜剤、潤滑剤などの全固形粉末の平均粒子径を０．
５μｍ以下とし、これらの固形粉末の全体の粒子表面の
水酸基濃度を６．０×１０１９〜１．２Ｘ １０２１（
固／ｇの範囲内にすると、過度な水酸基が存在する場合
のように、かえって分散性、充填性および配向性が劣化
されるということもなく、これら固形粉末粒子表面の適
度な濃度の水酸基が結合剤樹脂中の官能基と強固に結合
して、これらの固形粉末の分散性、充填性および配向性
が充分に向上され、電磁気的特性および耐久性に優れた
磁気記録媒体が得られる。The solid powder used in this invention, such as magnetic powder, abrasive, and lubricant, has an average particle size of 0.5 as a whole.
μm or less, and the concentration of hydroxyl groups on the particle surface of the entire solid powder is 6. Ox 1019~1.2 X 1021f[I
/g, and if the average particle size of the entire solid powder is larger than 0.5 μm,
In a magnetic recording medium containing these in the magnetic layer, for example, noise cannot be sufficiently reduced, and the surface smoothness cannot be made sufficiently smooth. In addition, the concentration of hydroxyl groups on the particle surface of the entire solid powder is 6.
If it is too low than 0X1019111i1/g, it will not be possible to bond sufficiently firmly with the functional group of the binder resin.
On the other hand, if it is too high than 1.2x 1021i1i1/g, too many hydroxyl groups will have an unfavorable effect on the dispersibility, filling property, and orientation of solid powders such as magnetic powders, polishing agents, and lubricants. The desired effect cannot be fully exerted. Therefore, the solid powder to be contained in the coating layer has an average particle diameter of 0.5 μm or less, and a concentration of hydroxyl groups on the particle surface of the entire solid powder (,Q
×I Q 19 to 1.2 . In addition, the concentration of hydroxyl groups on the particle surface of the entire solid powder is further 7.5x l 019 ~ 1.0
x 10”? within the range of surface/g, 7.5 x 10”
~5. It is more preferable that Ox 10"t [H/g) be within the range. In this way, the average particle diameter of all solid powders such as magnetic powder, abrasive agent, lubricant, etc. contained in the coating layer is 0.
5 μm or less, and the hydroxyl group concentration on the entire particle surface of these solid powders is 6.0×1019 to 1.2×1021 (
When the concentration of hydroxyl groups is within the solid/g range, the dispersibility, filling property, and orientation will not be deteriorated as would be the case if excessive hydroxyl groups are present, and an appropriate concentration of hydroxyl groups on the surface of these solid powder particles can be used. By strongly bonding with the functional groups in the binder resin, the dispersibility, filling properties, and orientation of these solid powders are sufficiently improved, and a magnetic recording medium with excellent electromagnetic properties and durability can be obtained.
このような平均粒子径が０．５μｍ以下の粒子の表面の
水酸基の濃度は、親水性化合物または疎水性化合物など
を被着することによって、６．０Ｘ１０１９〜１．２Ｘ
１０２’ ＋固／ｇの範囲内とされる。The concentration of hydroxyl groups on the surface of such particles with an average particle diameter of 0.5 μm or less can be increased from 6.0×1019 to 1.2× by coating with a hydrophilic compound or a hydrophobic compound.
It is assumed to be within the range of 102' + solid/g.
このように、これら固形粉末全体の粒子表面の水酸基の
濃度を調整するため、被着する親水性化合物としては、
たとえば、酸化アルミニウム、酸化ニッケル、酸化コバ
ルト、酸化クロム、酸化亜鉛、酸化チタンなどが挙げら
れる。これらの化合物の被着は、硫酸アルミニウム、硫
酸コバルト、硝酸ニッケル、塩化クロム、塩化亜鉛、塩
化チクンなどの水溶液中に固形粉末を分散させた後、ア
ルカリを添加して水酸化物沈澱として粒子表面に被着さ
せたり、アルカリ溶液を中和して固形分を粒子表面に被
着させ、次いで、１００〜１０００℃の温度で加熱する
などして行われる。In this way, in order to adjust the concentration of hydroxyl groups on the particle surface of these solid powders as a whole, the hydrophilic compound to be coated is
Examples include aluminum oxide, nickel oxide, cobalt oxide, chromium oxide, zinc oxide, titanium oxide, and the like. Adhesion of these compounds is achieved by dispersing solid powders in an aqueous solution of aluminum sulfate, cobalt sulfate, nickel nitrate, chromium chloride, zinc chloride, chikum chloride, etc., and then adding an alkali to form a hydroxide precipitate on the particle surface. The solid content is deposited on the particle surface by neutralizing an alkaline solution, and then heated at a temperature of 100 to 1000°C.
また、疎水性化合物としては、たとえば、酸化ケイ素、
炭化水素、界面活性剤などが挙げられ、これらの被着は
、たとえば、水ガラスなどのケイ素化合物をアルカリ水
溶液に溶解し、この溶液中に固形粉末を分散させた後、
炭酸ガスを吹き込んだり、酸を添加するなどの方法で中
和して、これらの疎水性化合物の水和物として粒子表面
に被着し、次いで、１００〜１０００℃の温度で加熱し
疎水性化処理するなどして行われる。また、固形粉末の
表面に疎水性炭化水素あるいは界面活性剤等による表面
被７処理を行って疎水性化することも可能であるが、無
機物による処理の方がより好ましい。In addition, examples of hydrophobic compounds include silicon oxide,
Examples include hydrocarbons, surfactants, etc., and these can be deposited by, for example, dissolving a silicon compound such as water glass in an alkaline aqueous solution, dispersing solid powder in this solution,
These hydrophobic compounds are neutralized by blowing in carbon dioxide or adding acid, and then adhered to the particle surface as hydrates of these hydrophobic compounds, and then heated at a temperature of 100 to 1000°C to make them hydrophobic. This is done by processing. It is also possible to make the surface of the solid powder hydrophobic by subjecting it to a surface treatment with a hydrophobic hydrocarbon or a surfactant, but treatment with an inorganic substance is more preferable.
上記の親水性化合物または疎水性化合物の被着は、被着
する固形粉末の粒子表面の水酸基濃度に応じて、いずれ
か−方あるいは両者を同時に被着してもよい。固形粉末
全体の粒子表面の水酸基の濃度は、これらの化合物の被
着量などによって調整され、親水性化合物が被着される
と固形粉末全体の粒子表面の水酸基の濃度が高くなり、
疎水性化合物が被着されると固形粉末全体のＦ、、′ｌ
ｌ裏表面水酸基の濃度が低くなる。The above hydrophilic compound or hydrophobic compound may be applied either or both at the same time depending on the hydroxyl group concentration on the particle surface of the solid powder to be applied. The concentration of hydroxyl groups on the particle surface of the entire solid powder is adjusted by the amount of these compounds deposited, etc. When a hydrophilic compound is deposited, the concentration of hydroxyl groups on the particle surface of the entire solid powder increases,
When the hydrophobic compound is deposited, the F,,′l of the entire solid powder
l The concentration of hydroxyl groups on the back surface becomes lower.
このようにして、全体の粒子表面の水酸基の濃度を６．
０Ｘ １０１９〜２．ｌＸ１０２１１固／ｇの範囲内と
した平均粒子径が０．５μｍ以下の固形粉末は、特に限
定されるものではないが、強いて挙げるとすれば、たと
えば、磁性粉末としては、Ｆｅ、ＦＣを主体として各種
金属を添加した全屈磁性粉末、ＣＯ％ Ｎ ｉなどの全
屈磁性粉末、あるいはこれらの合金磁性粉末、ｒ−Ｆｅ
２０３粉末、Ｆｅ３Ｏ４粉末、ｒ−Ｆｅ２０３とｆ？ｅ
３０４の中間酸化鉄粉末、ＣＯ含有ｒ−Ｆｅ２０３粉末
、ＣＯ含有Ｆｅ３Ｏ４粉末、バリウムフェライト磁性粉
末、および各種金属を添加したバリウムフェライト磁性
粉末などが好適なものとして挙げられる。In this way, the concentration of hydroxyl groups on the entire particle surface was reduced to 6.
0X 1019~2. Solid powders with an average particle size of 0.5 μm or less within the range of lX10211 solids/g are not particularly limited, but if forced to mention, for example, magnetic powders mainly include Fe and FC. Totally magnetic powders with various metals added, fully magnetically magnetic powders such as CO%Ni, or alloy magnetic powders of these, r-Fe
203 powder, Fe3O4 powder, r-Fe203 and f? e
Suitable examples include 304 intermediate iron oxide powder, CO-containing r-Fe203 powder, CO-containing Fe3O4 powder, barium ferrite magnetic powder, and barium ferrite magnetic powder added with various metals.
また、研磨剤、潤滑剤さらに帯電防止剤等のその他の固
形粉末としては、たとえば、α−Ｆｅ２０３粉末、Ｃｒ
２Ｏ３粉末、Ａｌ２Ｏ３粉末、Ｂａ５Ｏ４粉末、ＣａＣ
Ｏ３粉末、Ｍ ｇ Ｏ粉末、ＢａｃＯ３粉末、ＺｎＯ粉
末、Ｃｕ２Ｏ粉末、ＣｕＯ粉末、Ｓｉ３Ｎ＋粉末、Ｓｉ
Ｃ粉宋、Ｔ ｉ ０２粉末、Ｍ ＯＳ ２粉末、グラフ
ァイトおよびカーボンブランク等の炭素質粉末などが好
適なものとして挙げられる。Other solid powders such as abrasives, lubricants, and antistatic agents include, for example, α-Fe203 powder, Cr
2O3 powder, Al2O3 powder, Ba5O4 powder, CaC
O3 powder, MgO powder, BacO3 powder, ZnO powder, Cu2O powder, CuO powder, Si3N+ powder, Si
Suitable examples include carbonaceous powders such as C powder, T i 02 powder, M OS 2 powder, graphite, and carbon blank.
この発明の磁気記録媒体を製造するには常法に準じて行
えばよく、例えば、前記の全固形粉末の平均粒子径が０
．５μｍ以下で、かつ固形粉末全体の粒子表面の水酸基
の濃度が６．ＯＸ １０１ｇ〜１．２×ｌ Ｑ ２１個
／ｇの範囲内にある磁性粉末、研磨剤、潤滑剤などの固
形粉末を、結合剤樹脂、有機溶剤等とともに混合分散し
て磁性塗料または下塗層用塗料あるいはバックコート層
用塗料を凋製し、これをポリエステルフィルムなどの基
体上に、ロールコータ−など任意の塗布手段によって塗
布し、乾燥すればよい。The magnetic recording medium of the present invention may be manufactured according to a conventional method. For example, if the average particle size of the all-solid powder is 0.
．． 5 μm or less, and the concentration of hydroxyl groups on the particle surface of the entire solid powder is 6. OX 101g - 1.2xl Q Solid powder such as magnetic powder, abrasive, lubricant, etc. within the range of 21 pieces/g is mixed and dispersed with binder resin, organic solvent, etc. to form a magnetic paint or undercoat layer. The coating material for the coating or the coating material for the backcoat layer may be prepared, coated on a substrate such as a polyester film using any coating means such as a roll coater, and dried.
ここに用いる結合剤樹脂としては、塩化ビニル−酢酸ビ
ニル系共重合体、ポリビニルブチラール樹脂、繊維素系
樹脂、ポリウレタン系樹脂、ポリエステル系樹脂、イソ
シアネート化合物など従来汎用されている結合剤樹脂が
広く用いられる。As the binder resin used here, conventionally widely used binder resins such as vinyl chloride-vinyl acetate copolymer, polyvinyl butyral resin, cellulose resin, polyurethane resin, polyester resin, and isocyanate compound are widely used. It will be done.
また、有機溶剤としては、トルエン、メチルイソブチル
ケトン、メチルエチルケトン、シクロヘキサノン、テト
ラヒドロフラン、酢酸エチルなど従来から汎用されてい
る有機溶剤が、単独または二種以上混合して使用される
。Further, as the organic solvent, conventionally widely used organic solvents such as toluene, methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, and ethyl acetate are used alone or in a mixture of two or more.
なお、磁性塗料または下学雇用塗料あるいはバックコー
ト層用塗料中には、通常使用されている各種添加剤、た
とえば、分散剤、潤Ｗｌ剤などを任意に添加使用しても
よい。In addition, various commonly used additives such as dispersants, wetting agents, etc. may be optionally added to the magnetic paint, the lower grade paint, or the back coat layer paint.
次に、この発明の実施例について説明する。 Next, embodiments of the invention will be described.
実施例１
平均長径０．２５μｍ、軸比（長径／短径）１５／１の
ゲータイト粉末２０ｇをＩ Ｎ Ｎ ａ ＯＨ水ｌ容
液２１中に分散し、これに０．５モル／ｐの硫酸アルミ
ニウム２５ｍ１を加えて充分に分散しながら炭酸ガスを
吹き込み、ゲータイト粉末の表面にアルミナ水和物を被
着した。次いで、これをよく洗浄してから乾燥し、空気
中にて３００℃で加熱焼成した。次に、この焼成後のア
ルミナ被着へマタイト粉末２０ｇを１１のＩＮ−ＮａＱ
ｌ（水溶液中に分散し、１モル／！！のオルトケイ酸ソ
ーダ４０ｍｆｆを加えて攪拌した。充分に攪拌した後、
この懸濁液に炭酸ガスを吹き込み、ｐＨ１０以下に中和
して、ヘマタイト粉末の粒子表面にアルミナ水和物およ
びケイ酸水和物の被膜を形成した。次いで、７００℃の
温度で２時間加熱してケイ酸水和物の疎水性化処理を行
った。Example 1 20 g of goethite powder with an average major axis of 0.25 μm and an axial ratio (major axis/minor axis) of 15/1 was dispersed in 21 liters of IN Na OH aqueous solution, and 0.5 mol/p of sulfuric acid was added to this. 25 ml of aluminum was added and carbon dioxide gas was blown into the mixture while thoroughly dispersing it, thereby depositing alumina hydrate on the surface of the goethite powder. Next, this was thoroughly washed, dried, and fired in air at 300°C. Next, 20 g of matite powder was added to the alumina coated with 11 IN-NaQ after firing.
1 (dispersed in an aqueous solution, 40 mff of 1 mol/!! sodium orthosilicate was added and stirred. After thorough stirring,
Carbon dioxide gas was blown into this suspension to neutralize it to pH 10 or less, thereby forming a film of alumina hydrate and silicic acid hydrate on the surface of the hematite powder particles. Next, the silicic acid hydrate was hydrophobized by heating at a temperature of 700° C. for 2 hours.
次いで、粒子表面にアルミナ水和物と疎水性化されたシ
リカ被膜とを形成したヘマタイト粉末を、水素気流中、
５００℃で４時間加熱還元して、粒子表面にアルミナ被
膜および疎水性化されたシリカ被膜を有する金属鉄磁性
粉末を得た。この金属鉄磁性粉末は、保磁力が１６２０
エルステツド、飽和磁化量が１２１ ｅｍｕ／ｇ、 Ｂ
ＥＴ法による比表面積は６２＋ｖ？／ｇであった。また
、アルミナの被着量は、Ａ Ｉ ／ Ｆ ｅの原子換算
重量比で５重量％、疎水性化されたシリカの被着量は、
Ｓｉ／Ｆｅの原子換算重量比で２．５重量％であった。Next, hematite powder with alumina hydrate and hydrophobized silica coating formed on the particle surface was heated in a hydrogen stream.
The particles were thermally reduced at 500° C. for 4 hours to obtain metal iron magnetic powder having an alumina coating and a hydrophobicized silica coating on the particle surface. This metallic iron magnetic powder has a coercive force of 1620
Oersted, saturation magnetization is 121 emu/g, B
The specific surface area by ET method is 62+v? /g. In addition, the amount of alumina deposited was 5% by weight in terms of AI/Fe atomic weight ratio, and the amount of hydrophobized silica deposited was:
The Si/Fe atomic weight ratio was 2.5% by weight.
さらに粒子表面の水酸基濃度は４．５ｔ［ｌｉＩ／ ｎ
ｍであった。Furthermore, the concentration of hydroxyl groups on the particle surface is 4.5t[liI/n
It was m.
このようにして得られた金属鉄磁性粉末を使用し、
金泥鉄磁性粉末 １００重債部ＶＡＧＨ
（Ｕ、Ｃ，Ｃ社製、塩化ビ １０〃ニル−酢酸ビニル
−ビニルア
ルコール共重合体）
バンデフクスＴ−５２０１（大 ６ 〃ロ本インキ化
学工業社語、ポ
リウレタン）
ミリスチン酸 ５ 〃カーボンブ
ラック（平均粒子径 １ 〃０．０３μｍ、水酸基濃
度ｏ、ｉ個
／ ｎ ｍ以下）
メチルイソブチルケトン ８５〃トルエン
８５〃の組成からなる組成物を３１
容量のスチール製ボールミル中に入れ、これを７２時間
回転させ、よく分散させて磁性ペーストを調製した。そ
の後、この磁性ペーストに、トルエン４Ｑｉｉ部とコロ
ネートＬ（ロ本ポリウレタン工業社製、三官能性低分子
量イソシアネート化合物）２重量部をさらに加え、磁性
塗料を調製した。この磁性塗料を厚さ１２μｍのポリエ
ステルフィルム上に、乾Ｂｆ＆の塗布厚が４μｍとなる
ように塗布、乾燥し、鏡面加工処理を行った後、１／２
インチ幅に裁断して磁気テープをつくった。Using the metal iron magnetic powder obtained in this way, gold mud iron magnetic powder 100 heavy bond part VAGH
(Manufactured by U, C, C Company, vinyl chloride 10-vinyl acetate-vinyl alcohol copolymer) Vandefuchs T-5201 (large 6 〃Bon Ink Kagaku Kogyo Co., Ltd., polyurethane) Myristic acid 5〃Carbon black (average Particle size 1 0.03 μm, hydroxyl group concentration o, i pieces/nm or less) Methyl isobutyl ketone 85 Toluene
A composition consisting of 85〃 composition is 31
The magnetic paste was prepared by placing the magnetic paste in a high capacity steel ball mill and rotating it for 72 hours to ensure good dispersion. Thereafter, 4 Qii parts of toluene and 2 parts by weight of Coronate L (a trifunctional low molecular weight isocyanate compound manufactured by Romoto Polyurethane Industries, Ltd.) were further added to this magnetic paste to prepare a magnetic paint. This magnetic paint was applied onto a polyester film with a thickness of 12 μm so that the coating thickness of dry Bf& was 4 μm, dried, mirror-finished, and then 1/2
I cut it into inch-wide pieces to make magnetic tape.
実施例２
平均長径０．０５μｍ、板伏比（長径／短径）３／１、
保磁カフ５０エルステツド、飽和磁化量５５ｅｍｕ／ｇ
、ＢＥＴ法による比表面積６１ｍ／ｇのバリウムフェラ
イト粉末１００ｇを、ｌＮＮａ０ Ｈ水溶液２１中に懸
濁させよく分散させた。次いで、これに１モル／β溶ン
夜のオルトケイ酸ソーダ２８０ｍｆｆを加えてよく攪拌
しながら炭酸ガスを通気し、溶液のｐＨを９以下にした
。これを水洗、乾燥後、７００℃で２時間空気中で加熱
処理し、表面のケイ酸水和物を疎水性化処理した。この
ようにして得られたバリウムフェライト粉末は、保磁力
が７５０エルステ・７ド、飽和磁化量が５２ ｅｍｕ／
ｇ 、 Ｂ ＥＴ法による比表面積が６０ｍ／ｇで、
疎水性化されたシリカの被着量は、Ｓｉ／バリウムフェ
ライトの原子換算重量比で２．９重量％であった。さら
に粒子表面の水酸基濃度は６．８個／ ｎ ｒｄであっ
た。次いで、このようにして得られたバリウムフェライ
ト粉末を使用し、実施例１と同様にして磁気テープをつ
くった。Example 2 Average major axis 0.05 μm, board ratio (major axis/minor axis) 3/1,
Retention cuff 50 oersted, saturation magnetization 55 emu/g
, 100 g of barium ferrite powder having a specific surface area of 61 m/g by the BET method was suspended and well dispersed in an IN Na0 H aqueous solution 21. Next, 280 mff of 1 mol/β-soluble sodium orthosilicate was added to the solution, and carbon dioxide gas was bubbled through the solution while stirring well to bring the pH of the solution to 9 or less. After washing with water and drying, this was heat-treated in air at 700° C. for 2 hours to make the silicic acid hydrate on the surface hydrophobic. The barium ferrite powder thus obtained has a coercive force of 750 oerste·7 de and a saturation magnetization of 52 emu/
g, B ET method specific surface area is 60 m/g,
The amount of hydrophobized silica deposited was 2.9% by weight in Si/barium ferrite atomic weight ratio. Furthermore, the concentration of hydroxyl groups on the particle surface was 6.8/nrd. Next, a magnetic tape was produced in the same manner as in Example 1 using the barium ferrite powder thus obtained.
比較例１
実施例１において、表面に被覆されたケイ酸水和物の疎
水性化処理を省いた以外は、実施例１と同様にして、保
磁力が１５９０エルステツド、飽和磁化量がｌ ２０
ｅｍｕ／ ｇ、’ Ｂ ＥＴ法による比表面積が６３ｔ
＋？／ｇで、アルミナの被着量がＡｌ／Ｆｅの原子換算
重量比で５重量％、ケイ酸水和物の被着量がＳ ｉ ／
Ｆ ｅの原子換算重量比で０．５重量％、粒子表面の
水酸基濃度が１２．２（固／ ｎ ｍの金属鉄磁性粉末
を得、磁気テープをつくった。Comparative Example 1 A sample was prepared in the same manner as in Example 1, except that the hydrophobic treatment of the silicic acid hydrate coated on the surface was omitted, so that the coercive force was 1590 oersted and the saturation magnetization was l20
emu/g,'B Specific surface area by ET method is 63t
+? /g, the amount of alumina deposited is 5% by weight in terms of Al/Fe atomic weight ratio, and the amount of silicic acid hydrate deposited is S i /g.
Metallic iron magnetic powder with an atomic weight ratio of Fe of 0.5% by weight and a hydroxyl group concentration on the particle surface of 12.2 (hard/nm) was obtained, and a magnetic tape was made.
比較例２
実施例２において、ケイ酸水和物のバリウムフェライト
粉末粒子表面への被着およびケイ酸水和物の疎水性化処
理を省き、磁性塗料の組成において実施例２で使用した
磁性粉末に代えて、保磁力が７５０エルステツド、飽和
磁化量が５４ ｅｍｕ／ｇ、ＢＥＴ法による比表面積が
６１ｍ／ｇで、粒子表面の水酸基濃度が１３．５ｆ固／
ｎ ｍのバリウムフェライト粉末を使用した以外は、
実施例２と同様にして磁気テープをつくった。Comparative Example 2 In Example 2, the adhesion of silicic acid hydrate to the surface of barium ferrite powder particles and the hydrophobic treatment of silicic acid hydrate were omitted, and the magnetic powder used in Example 2 was used in the composition of the magnetic paint. Instead, the coercive force is 750 oersted, the saturation magnetization is 54 emu/g, the specific surface area by BET method is 61 m/g, and the hydroxyl group concentration on the particle surface is 13.5 f/g.
Except that barium ferrite powder of nm was used.
A magnetic tape was produced in the same manner as in Example 2.
比較例３
実施例１において、平均長径０．２５μｍ、軸比（長径
／短径）１５／１のゲータイト粉末に代えて、平均長径
０．５７μｍ、軸比１５／１のゲータイト粉末を用いた
以外は、実施例１と同様にして保磁力が１１００エルス
テツド、飽和磁化量が１３５ｅｍｕ／ｇ、ＢＥＴ法によ
る比表面積が３５ｍ／ｇで、アルミナの被着量がＡ １
／ Ｆ ｅの原子換算重量比で５重量％、疎水性化さ
れたシリカの被着量が３ ｉ ／ Ｆ ｅの原子換算重
量比で０．７重量％、粒子表面の水酸基濃度が７．５（
円／ ｎ ｍの金属鉄磁性粉末を得、磁気テープをつく
った。Comparative Example 3 In Example 1, goethite powder with an average major axis of 0.57 μm and an axial ratio of 15/1 was used instead of the goethite powder with an average major axis of 0.25 μm and an axial ratio (major axis/minor axis) of 15/1. As in Example 1, the coercive force was 1100 oersted, the saturation magnetization was 135 emu/g, the specific surface area by BET method was 35 m/g, and the amount of alumina deposited was A1.
The atomic weight ratio of / Fe is 5% by weight, the amount of hydrophobized silica is 3 i / Fe, the atomic weight ratio is 0.7% by weight, and the hydroxyl group concentration on the particle surface is 7.5. (
A metal iron magnetic powder of yen/nm was obtained and a magnetic tape was made.
比較例４
実施例２において、平均長径０．Ｏ５μｍ、板状比（長
径／短径）３／ｌ、保磁カフ５０エルステツド、飽和磁
化ｆｆ１５５ ｅｍｕ／ ｇ、 Ｂ ＥＴ法による比表
面［６１ｍ／ｇのバリウムフェライト粉末に代えて、平
均長径０．２μｍ、板状比３／１、保磁力が３８０エル
ステツド、飽和磁化ｍ ５６ ｅｍｕ／ ｇ、ＢＥＴ法
による比表面積が２８ ｒｒｒ ／ ｇのバリウムフェ
ライトを用いた以外は実施例２と同様にして、保磁力が
３９０エルステンド、飽和磁化量が５５ ｅｍｕ／ ｇ
、 Ｂ ＥＴ法による比表面積が２７ｍ／ｇで、疎水性
化されたシリカの被、ＩＦｆｆｉがＳｉ／バリウムフェ
ライトの原子換算重量比で１重量％、粒子表面の水酸基
濃度が８．５（固／ ｎ ｍのバリウムフェライト粉末
を得、磁気テープをつくった。Comparative Example 4 In Example 2, the average major axis was 0. O 5 μm, plate ratio (major axis/minor axis) 3/l, coercive cuff 50 oersted, saturation magnetization ff155 emu/g, specific surface by BET method [instead of barium ferrite powder of 61 m/g, average major axis 0. Storage was carried out in the same manner as in Example 2, except that barium ferrite having a diameter of 2 μm, a plate ratio of 3/1, a coercive force of 380 oersted, a saturation magnetization of m 56 emu/g, and a specific surface area of 28 rrr/g by the BET method was used. Magnetic force is 390 Oerstend, saturation magnetization is 55 emu/g
, the specific surface area by the BET method is 27 m/g, the IFffi of the hydrophobized silica coating is 1% by weight in terms of Si/barium ferrite atomic weight ratio, and the hydroxyl group concentration on the particle surface is 8.5 (solid/ Barium ferrite powder of nm size was obtained and a magnetic tape was made.
各実施例および比較例で得られた磁気テープについて、
角型比、残留磁束密度、耐久性、磁性層の表面平滑性、
全固形粉末の平均粒子径および固形粉末全体の粒子表面
の水酸基の濃度を調べた。Regarding the magnetic tapes obtained in each example and comparative example,
Squareness ratio, residual magnetic flux density, durability, surface smoothness of magnetic layer,
The average particle diameter of all solid powders and the concentration of hydroxyl groups on the particle surface of all solid powders were investigated.
角型比の測定は、実施例１．比較例１および３について
は水平方向の角型比を測定し、実施例２゜比較例２およ
び４については垂直方向の角型比を測定した。また耐久
性は市販ＶＴＲを使用し、−５℃の恒温室中で静止画像
百住を行った時の出力が３ｄＢ低下するまでの時間を測
定することにより判定した。さらに全固形粉末の平均粒
子径は、透過型電子顕微鏡により観察された１０００固
の粒子の寸法を測定し、その平均値から求めた。また固
形粉末全体の粒子表面の水酸基の濃度は微量電器天秤を
用いて２０℃におけろ水吸着等点線を測定し、ＢＥＴ式
により物理吸着水分量を測定して求めた。さらに表面平
滑性は、触針式粗さ計を使用し、触針速度０．０６ｃｍ
／秒、カットオフ０ 、０８ｍｍの条件下で磁性層の表
面粗さくＣ，Ｌ、Ａ、）を測定し、実施例１を基準とし
て下記の式に従って算出される相対値で表面平滑性の良
否を判断した。The squareness ratio was measured in Example 1. For Comparative Examples 1 and 3, the squareness ratio in the horizontal direction was measured, and for Example 2 and Comparative Examples 2 and 4, the squareness ratio in the vertical direction was measured. Furthermore, durability was determined by using a commercially available VTR and measuring the time until the output decreased by 3 dB when still images were viewed in a constant temperature room at -5°C. Further, the average particle diameter of the total solid powder was determined from the average value of the dimensions of 1000 solid particles observed using a transmission electron microscope. Further, the concentration of hydroxyl groups on the particle surface of the entire solid powder was determined by measuring the water adsorption isodotted line at 20° C. using a microelectronic balance, and measuring the amount of physically adsorbed water using the BET equation. Furthermore, the surface smoothness was measured using a stylus-type roughness meter at a stylus speed of 0.06 cm.
The surface roughness (C, L, A,) of the magnetic layer was measured under the conditions of 1/sec, cutoff 0, 08 mm, and the quality of the surface smoothness was determined by the relative value calculated according to the following formula based on Example 1. judged.
下記第１表はその結果である。Table 1 below shows the results.
上記第１表から明らかなように、実施例１および２で１
４られた磁気テープは、いずれも比較例工ないし４で得
られた磁気テープに比して、角型比および残留磁束密度
が高く、耐久性がよくて、さらに表面平滑性もよく、こ
のことからこの発明で得られる磁気記録媒体は、磁性層
中に含まれる固形粉末の分肢性、充填性および配向性が
向上され、電磁気的特性および耐久性が一段と向上され
ていることがわかる。As is clear from Table 1 above, in Examples 1 and 2, 1
All of the magnetic tapes obtained in Comparative Examples 4 and 4 had higher squareness ratios and residual magnetic flux densities, better durability, and better surface smoothness. It can be seen from the above that the magnetic recording medium obtained according to the present invention has improved branching properties, filling properties, and orientation of the solid powder contained in the magnetic layer, and has further improved electromagnetic properties and durability.
Claims (1)
成分とを含む塗布層を設けた磁気記録媒体において、塗
布層中に含まれる全固形粉末の平均粒子径が０．５μｍ
以下で、かつ固形粉末全体の粒子表面の水酸基の濃度が
６．０×１０＾１＾９〜１．２×１０＾２＾１個／ｇの
範囲内にあることを特徴とする磁気記録媒体1. In a magnetic recording medium in which a coating layer containing a solid powder and a binder component for dispersing and binding the solid powder is provided on a substrate, the average particle diameter of all the solid powder contained in the coating layer is 0.5 μm.
A magnetic recording medium which is as follows, and the concentration of hydroxyl groups on the particle surface of the entire solid powder is within the range of 6.0×10^1^9 to 1.2×10^2^1/g.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14410686A JPS63818A (en) | 1986-06-20 | 1986-06-20 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14410686A JPS63818A (en) | 1986-06-20 | 1986-06-20 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63818A true JPS63818A (en) | 1988-01-05 |
Family
ID=15354324
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14410686A Pending JPS63818A (en) | 1986-06-20 | 1986-06-20 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63818A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008084900A (en) * | 2006-09-26 | 2008-04-10 | Dowa Holdings Co Ltd | Magnetic powder for coating type magnetic recording medium, its production process and magnetic recording medium |
| JP2012080116A (en) * | 2011-11-30 | 2012-04-19 | Dowa Holdings Co Ltd | Magnetic powder for coating type magnetic recording medium, production method for the same and magnetic recording medium |
-
1986
- 1986-06-20 JP JP14410686A patent/JPS63818A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008084900A (en) * | 2006-09-26 | 2008-04-10 | Dowa Holdings Co Ltd | Magnetic powder for coating type magnetic recording medium, its production process and magnetic recording medium |
| JP2012080116A (en) * | 2011-11-30 | 2012-04-19 | Dowa Holdings Co Ltd | Magnetic powder for coating type magnetic recording medium, production method for the same and magnetic recording medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4956220A (en) | Magnetic recording medium | |
| EP0660309B1 (en) | Non-magnetic undercoat layer for magnetic recording medium, magnetic recording medium and non-magnetic particles | |
| US6544647B1 (en) | Non-magnetic composite particles, process for producing the same and magnetic recording medium using the same | |
| US6432377B1 (en) | Particles for non-magnetic undercoat layer of magnetic recording medium, method thereof and magnetic recording medium | |
| JPS631003A (en) | Magnetic powder | |
| JPS63818A (en) | Magnetic recording medium | |
| US6569530B2 (en) | Magnetic recording medium and magnetic composite particles or magnetic recording medium | |
| JP3398404B2 (en) | Manufacturing method of magnetic particle powder for magnetic recording | |
| JP2906075B2 (en) | Manufacturing method of magnetic particle powder for magnetic recording | |
| US5552072A (en) | Coated acicular fine particulate materials, processes for preparing same and use thereof | |
| US6294242B1 (en) | Magnetic recording medium | |
| JPS60217529A (en) | Magnetic powder for magnetic recording medium | |
| JP3763353B2 (en) | Hematite powder for nonmagnetic underlayer of magnetic recording medium, nonmagnetic underlayer and magnetic recording medium of magnetic recording medium using hematite powder for nonmagnetic underlayer | |
| EP1253585A1 (en) | Composite magnetic particles containing iron, process for producing the same and magnetic recording medium | |
| JPH04228502A (en) | Acicular metallic iron fine particle containing carbon, its production and magnetic paint composition and magnetic recording medium containing the particle | |
| JP2002329310A (en) | Surface reforming magnetic particle powder for magnetic recording medium, surface reforming filler material for magnetic recording medium and surface reforming nonmagnetic particle powder for nonmagnetic ground surface layer for magnetic recording medium as well as magnetic recording medium | |
| JP3661738B2 (en) | Magnetic recording medium substrate having non-magnetic underlayer and magnetic recording medium using the substrate | |
| JP2002008915A (en) | Composite magnetic grain powder for magnetic recording medium, its manufacturing method, and the magnetic recording medium | |
| EP0941966B1 (en) | Acicular hematite particles and magnetic recording medium | |
| JP2001160212A (en) | Non-magnetic particle powder for non-magnetic base layer of magnetic recording medium and magnetic recording medium | |
| JP3398430B2 (en) | Manufacturing method of magnetic particle powder for magnetic recording | |
| JP2965606B2 (en) | Method for producing metal magnetic powder | |
| JP4352270B2 (en) | Hematite particle powder for nonmagnetic underlayer of magnetic recording medium and magnetic recording medium | |
| JPH10241148A (en) | Magnetic recording medium | |
| JP3661733B2 (en) | Magnetic recording medium |