JPH01276424A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH01276424A JPH01276424A JP10331988A JP10331988A JPH01276424A JP H01276424 A JPH01276424 A JP H01276424A JP 10331988 A JP10331988 A JP 10331988A JP 10331988 A JP10331988 A JP 10331988A JP H01276424 A JPH01276424 A JP H01276424A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- oxide
- recording medium
- back coat
- coat layer
- 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.)
- Granted
Links
- 239000000843 powder Substances 0.000 claims abstract description 19
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 claims abstract description 8
- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910000505 Al2TiO5 Inorganic materials 0.000 claims abstract description 4
- 229910052916 barium silicate Inorganic materials 0.000 claims abstract description 4
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910002113 barium titanate Inorganic materials 0.000 claims abstract description 4
- HMOQPOVBDRFNIU-UHFFFAOYSA-N barium(2+);dioxido(oxo)silane Chemical compound [Ba+2].[O-][Si]([O-])=O HMOQPOVBDRFNIU-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910052878 cordierite Inorganic materials 0.000 claims abstract description 4
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 claims abstract description 4
- NKZSPGSOXYXWQA-UHFFFAOYSA-N dioxido(oxo)titanium;lead(2+) Chemical compound [Pb+2].[O-][Ti]([O-])=O NKZSPGSOXYXWQA-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910001940 europium oxide Inorganic materials 0.000 claims abstract description 4
- AEBZCFFCDTZXHP-UHFFFAOYSA-N europium(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Eu+3].[Eu+3] AEBZCFFCDTZXHP-UHFFFAOYSA-N 0.000 claims abstract description 4
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 claims abstract description 4
- AABBHSMFGKYLKE-SNAWJCMRSA-N propan-2-yl (e)-but-2-enoate Chemical compound C\C=C\C(=O)OC(C)C AABBHSMFGKYLKE-SNAWJCMRSA-N 0.000 claims abstract description 4
- 229910001954 samarium oxide Inorganic materials 0.000 claims abstract description 4
- 229940075630 samarium oxide Drugs 0.000 claims abstract description 4
- FKTOIHSPIPYAPE-UHFFFAOYSA-N samarium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[Sm+3].[Sm+3] FKTOIHSPIPYAPE-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910003451 terbium oxide Inorganic materials 0.000 claims abstract description 4
- SCRZPWWVSXWCMC-UHFFFAOYSA-N terbium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[Tb+3].[Tb+3] SCRZPWWVSXWCMC-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910052451 lead zirconate titanate Inorganic materials 0.000 claims description 5
- 150000001875 compounds Chemical class 0.000 claims description 3
- PQCCZSBUXOQGIU-UHFFFAOYSA-N [La].[Pb] Chemical compound [La].[Pb] PQCCZSBUXOQGIU-UHFFFAOYSA-N 0.000 claims description 2
- 238000012546 transfer Methods 0.000 abstract description 9
- 239000011230 binding agent Substances 0.000 abstract description 7
- 239000006229 carbon black Substances 0.000 abstract description 6
- 238000012360 testing method Methods 0.000 description 10
- 239000003973 paint Substances 0.000 description 9
- 239000000203 mixture Substances 0.000 description 7
- 239000002245 particle Substances 0.000 description 7
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 6
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 229920002799 BoPET Polymers 0.000 description 5
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 4
- 230000003746 surface roughness Effects 0.000 description 4
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 230000006866 deterioration Effects 0.000 description 3
- 239000010419 fine particle Substances 0.000 description 3
- -1 polyethylene terephthalate Polymers 0.000 description 3
- 229920002635 polyurethane Polymers 0.000 description 3
- 239000004814 polyurethane Substances 0.000 description 3
- IIZPXYDJLKNOIY-JXPKJXOSSA-N 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine Chemical compound CCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCC\C=C/C\C=C/C\C=C/C\C=C/CCCCC IIZPXYDJLKNOIY-JXPKJXOSSA-N 0.000 description 2
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 239000000020 Nitrocellulose Substances 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000003490 calendering Methods 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002148 esters Chemical class 0.000 description 2
- 239000000787 lecithin Substances 0.000 description 2
- 235000010445 lecithin Nutrition 0.000 description 2
- 229940067606 lecithin Drugs 0.000 description 2
- 229920001220 nitrocellulos Polymers 0.000 description 2
- 229920000728 polyester Polymers 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 229920002451 polyvinyl alcohol Polymers 0.000 description 2
- 229920000915 polyvinyl chloride Polymers 0.000 description 2
- 239000004800 polyvinyl chloride Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- QMMJWQMCMRUYTG-UHFFFAOYSA-N 1,2,4,5-tetrachloro-3-(trifluoromethyl)benzene Chemical compound FC(F)(F)C1=C(Cl)C(Cl)=CC(Cl)=C1Cl QMMJWQMCMRUYTG-UHFFFAOYSA-N 0.000 description 1
- OEPOKWHJYJXUGD-UHFFFAOYSA-N 2-(3-phenylmethoxyphenyl)-1,3-thiazole-4-carbaldehyde Chemical compound O=CC1=CSC(C=2C=C(OCC=3C=CC=CC=3)C=CC=2)=N1 OEPOKWHJYJXUGD-UHFFFAOYSA-N 0.000 description 1
- 229920001747 Cellulose diacetate Polymers 0.000 description 1
- 229920002284 Cellulose triacetate Polymers 0.000 description 1
- 229920000742 Cotton Polymers 0.000 description 1
- 239000001856 Ethyl cellulose Substances 0.000 description 1
- ZZSNKZQZMQGXPY-UHFFFAOYSA-N Ethyl cellulose Chemical compound CCOCC1OC(OC)C(OCC)C(OCC)C1OC1C(O)C(O)C(OC)C(CO)O1 ZZSNKZQZMQGXPY-UHFFFAOYSA-N 0.000 description 1
- 229920000459 Nitrile rubber Polymers 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 239000004734 Polyphenylene sulfide Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 description 1
- NNLVGZFZQQXQNW-ADJNRHBOSA-N [(2r,3r,4s,5r,6s)-4,5-diacetyloxy-3-[(2s,3r,4s,5r,6r)-3,4,5-triacetyloxy-6-(acetyloxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6s)-4,5,6-triacetyloxy-2-(acetyloxymethyl)oxan-3-yl]oxyoxan-2-yl]methyl acetate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](OC(C)=O)[C@H]1OC(C)=O)O[C@H]1[C@@H]([C@@H](OC(C)=O)[C@H](OC(C)=O)[C@@H](COC(C)=O)O1)OC(C)=O)COC(=O)C)[C@@H]1[C@@H](COC(C)=O)O[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]1OC(C)=O NNLVGZFZQQXQNW-ADJNRHBOSA-N 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229920000180 alkyd Polymers 0.000 description 1
- 239000002216 antistatic agent Substances 0.000 description 1
- 239000004760 aramid Substances 0.000 description 1
- 229920003235 aromatic polyamide Polymers 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 235000010216 calcium carbonate Nutrition 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 235000019325 ethyl cellulose Nutrition 0.000 description 1
- 229920001249 ethyl cellulose Polymers 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 239000006247 magnetic powder Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 239000004014 plasticizer Substances 0.000 description 1
- 229920002037 poly(vinyl butyral) polymer Polymers 0.000 description 1
- 229920002239 polyacrylonitrile Polymers 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920000069 polyphenylene sulfide Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 229920002689 polyvinyl acetate Polymers 0.000 description 1
- 239000011118 polyvinyl acetate Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000012756 surface treatment agent Substances 0.000 description 1
- 229920006163 vinyl copolymer Polymers 0.000 description 1
Landscapes
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、磁気テープ、磁気ディスク及び磁気ドラム等
の磁気記録媒体、特に、走行性が安定し、且つバックコ
ート層の磁性層への転写が生じず、従って該転写による
磁気特性の低下が起こらない磁気記録媒体に関する。Detailed Description of the Invention [Industrial Field of Application] The present invention relates to magnetic recording media such as magnetic tapes, magnetic disks, and magnetic drums, particularly those having stable running properties and transfer of a back coat layer to a magnetic layer. The present invention relates to a magnetic recording medium in which no deterioration of magnetic properties occurs due to the transfer.
高性能の磁気記録媒体（特に磁気テープ）では、良好な
電磁特性を得るために、表面性の良い支持体（非磁性）
を用い、また磁性層を該支持体上に塗設後カレンダリン
グ等の表面仕上げをする必要があるが、支持体の表面性
が良すぎると、また磁気記録媒体が帯電すると、磁気記
録媒体の走行性が不良になる。そこで、通常、このよう
な不良発生の防止手段として、支持体の裏面に、カーボ
ン及びバインダーを主成分とするバックコート層を設け
ることが行われている。For high-performance magnetic recording media (especially magnetic tapes), supports with good surface properties (non-magnetic) are used to obtain good electromagnetic properties.
It is necessary to perform surface finishing such as calendering after coating the magnetic layer on the support, but if the surface properties of the support are too good or if the magnetic recording medium is charged, the magnetic recording medium will deteriorate. Running performance becomes poor. Therefore, as a means to prevent the occurrence of such defects, a back coat layer containing carbon and a binder as main components is usually provided on the back surface of the support.
しかしながら、磁気テープは、製造時及び使用時にテー
プを巻き取った状態にするため、表面の粗いバックコー
ト層を施すと、バックコート層が磁性層に転写し、その
結果磁性層の表面状態が損なわれ、磁気特性が低下する
問題が生じる。However, since magnetic tape is wound up during manufacturing and use, if a back coat layer with a rough surface is applied, the back coat layer will be transferred to the magnetic layer, resulting in damage to the surface condition of the magnetic layer. This causes a problem of deterioration of magnetic properties.
そこで、バックコート層に配合するカーボンの粒子を微
粒子化することが検討されているが、この方法では、バ
ックコート層の表面性が良くなりすぎる結果、粘着傾向
が生じ、ガイドピン、キャプスタン等の接触部による障
害により、走行性が充分には改良されない。Therefore, it is being considered to make the carbon particles blended into the back coat layer into fine particles, but this method results in the surface properties of the back coat layer being too good, resulting in a tendency to stick to the guide pins, capstans, etc. Due to obstacles caused by contact areas, running performance cannot be sufficiently improved.
また、上述の点を考慮し、粒子径が０．１ｕｍ以下の微
粒子無機粉末（Ｔｉｅ、、ＣａＣＯ３、ＺｎＯ等）又は
微粒子の有機物粉末をバックコート層に添加する試みが
多数提案されているが、何れの場合も、繰返し走行後、
摩擦係数が上昇する等、走行性が充分に改良されていな
い。 ゛
従って、本発明の目的は、走行性が安定し、且つバック
コート層の磁性層への転写が生じず、従って該転写によ
る磁気特性の低下が起こらない磁気記録媒体を提供する
ことにある。In addition, in consideration of the above points, many attempts have been proposed to add fine particle inorganic powder (Tie, CaCO3, ZnO, etc.) or fine particle organic powder with a particle size of 0.1 um or less to the back coat layer. In either case, after repeated running,
The running performance has not been sufficiently improved as the coefficient of friction has increased. Therefore, an object of the present invention is to provide a magnetic recording medium that has stable running properties and does not cause transfer of the backcoat layer to the magnetic layer, and therefore does not cause deterioration of magnetic properties due to the transfer.
本発明者らは、鋭意研究した結果、バックコート層中に
特定の無機粉末を含有させることにより、繰返し走行前
の摩擦係数が低く且つ繰返し走行後の摩擦係数の上昇が
少な（、またテープを巻き取った状態で保存しても磁性
層の表面粗さが悪化しない（表面状態が川なわれない）
磁気記録媒体が得られること、即ち前記目的を達成する
磁気記録媒体が得られることを知見した。As a result of extensive research, the present inventors found that by incorporating a specific inorganic powder into the back coat layer, the friction coefficient before repeated running is low and the increase in the friction coefficient after repeated running is small (and the tape Even when stored in a rolled state, the surface roughness of the magnetic layer does not deteriorate (the surface condition does not change)
It has been found that a magnetic recording medium can be obtained, that is, a magnetic recording medium that achieves the above object can be obtained.
本発明は、上記知見に基づきなされたもので、非磁性支
持体の一方の面に磁性層を設け、他方の面にバックコー
ト層を設けてなる磁気記録媒体において、上記バックコ
ート層中に、下記化合物の無機粉末群から選択された少
なくきも１種を含有させることを特徴とする磁気記録媒
体を提供するものである。The present invention has been made based on the above findings, and provides a magnetic recording medium in which a magnetic layer is provided on one surface of a non-magnetic support and a back coat layer is provided on the other surface, in which the back coat layer includes: The present invention provides a magnetic recording medium characterized by containing at least one kind selected from the inorganic powder group of the following compounds.
酸化ランタン、酸化サマリウム、酸化テルビウム、酸化
ユーロピウム、酸化イツトリウム、チタン酸バリウム、
チタン酸鉛、チタン酸ジルコン酸鉛、チタン酸ジルコン
酸ランタン鉛、コーディエライト、チタン酸アルミニウ
ム及び硅酸バリウム。Lanthanum oxide, samarium oxide, terbium oxide, europium oxide, yttrium oxide, barium titanate,
Lead titanate, lead zirconate titanate, lanthanum lead zirconate titanate, cordierite, aluminum titanate and barium silicate.
以下、本発明の磁気記録媒体について詳述する。The magnetic recording medium of the present invention will be described in detail below.
本発明の磁気記録媒体のバックコート層に用いられる前
記化合物の無機粉末としては、針状、粒状又は球状の何
れの形状のものでも良く、針状無機粉末を用いる場合は
長軸長が０．０５〜０．５μｍで短軸長が０．００５〜
０．１μｍの粒子サイズのものが好ましく、粒状又は球
状無機粉末を用いる場合は粒子径が０．００５〜０．１
μｍの粒子サイズのものが好ましい。The inorganic powder of the compound used in the back coat layer of the magnetic recording medium of the present invention may be acicular, granular, or spherical, and when acicular inorganic powder is used, the major axis length is 0. 05~0.5μm and short axis length is 0.005~
A particle size of 0.1 μm is preferable, and when using granular or spherical inorganic powder, the particle size is 0.005 to 0.1
Particle sizes of μm are preferred.
また、上記無機粉末の内、酸化ランタン、酸化サマリウ
ム、酸化テルビウム、酸化ユーロピウム及び酸化イツト
リウムについては針状のものが好ましく、チタン酸バリ
ウム、チタン酸鉛、チタン酸ジルコン酸鉛、チタン酸ジ
ルコン酸ランタン鉛、コーディエライト、チタン酸アル
ミニウム及び硅酸バリウムについては粒状又は球状のも
のが好ましい。Among the above inorganic powders, lanthanum oxide, samarium oxide, terbium oxide, europium oxide, and yttrium oxide are preferably needle-shaped, such as barium titanate, lead titanate, lead zirconate titanate, and lanthanum zirconate titanate. As for lead, cordierite, aluminum titanate, and barium silicate, granular or spherical ones are preferable.
上記無機粉末の使用量は、バインダー１００１ｉ量部に
対し、好ましくは１〜７０重量部、更に好ましくは２〜
２０重量部であり、１重量部未満であると、磁気記録媒
体の走行性が不十分である。The amount of the inorganic powder used is preferably 1 to 70 parts by weight, more preferably 2 to 70 parts by weight, based on 1001i parts of the binder.
If the amount is 20 parts by weight and less than 1 part by weight, the running properties of the magnetic recording medium will be insufficient.
また７０ｆｆｉ１部超であると、接着性の低下により粉
落ち現象が起こり、ドロップアウトの原因となる。Moreover, if the amount exceeds 1 part of 70ffi, a powder falling phenomenon occurs due to a decrease in adhesion, which causes dropout.
本発明の磁気記録媒体のバックコート層には、この種の
バックコート層に通常含有されるバインダー、例えば、
ポリウレタン、ポリエステル、ポリ塩化ビニル、塩化ビ
ニル／耐酸ビニル共重合体、塩化ビニル／酢酸ビニル／
ポリビニルアルコール共重合体、ポリアクリルニトリル
、ニトリルゴム、エポキシ樹脂、アルキッド樹脂、ポリ
アミド、ポリアクリル酸エステル、ポリメタクリル酸エ
ステル、ポリ酢酸ビニル、ポリビニルブチラール、塩化
ビニリデン、硝化綿、マレイン酸変性塩化ビニル／ 酢
酸ビニル共重合体、ニトロセルロース、エチルセルロー
ス等が用いられる。The back coat layer of the magnetic recording medium of the present invention contains binders that are normally contained in this type of back coat layer, such as
Polyurethane, polyester, polyvinyl chloride, vinyl chloride/acid-resistant vinyl copolymer, vinyl chloride/vinyl acetate/
Polyvinyl alcohol copolymer, polyacrylonitrile, nitrile rubber, epoxy resin, alkyd resin, polyamide, polyacrylic ester, polymethacrylic ester, polyvinyl acetate, polyvinyl butyral, vinylidene chloride, nitrified cotton, maleic acid-modified vinyl chloride/ Vinyl acetate copolymer, nitrocellulose, ethylcellulose, etc. are used.
また、本発明の磁気記録媒体のバックコート層には、前
記無機粉末と共にカーボンブラックを併用することが好
ましい。このカーボンブラックの使用量は、前記バイン
ダー１００重量部に対し、好ましくは２０〜６０重量部
である。Further, it is preferable to use carbon black together with the inorganic powder in the back coat layer of the magnetic recording medium of the present invention. The amount of carbon black used is preferably 20 to 60 parts by weight based on 100 parts by weight of the binder.
また、本発明の磁気記録媒体に用いられる非磁性支持体
としては、磁気記録媒体に用いられる通常のもの、例え
ば、ポリエチレンテレフタレート（ＰＥＴ）のようなポ
リエステル；ポリエチレン、ポリプロピレン等のポリオ
レフィン；セルローストリアセテート、セルロースジア
セテート等のセルロース誘導体；ポリカーボネート；ポ
リ塩化ビニル；ポリイミド；芳香族ポリアミド、ポリフ
ェニレンサルファイド等のプラスチックや、ＡＩ、Ｃｕ
等の金属；祇等が挙げられ、これらの支持体の表面をコ
ロナ放電、放射線、紫外線等で処理したもの或いは適当
な樹脂でプレコートしたものを用いることもできる。こ
の非磁性支持体の形態は、フィルム、テープ、シート、
ディスク、カード、ドラム等、何れの形態でも良い。In addition, the non-magnetic support used in the magnetic recording medium of the present invention includes those commonly used in magnetic recording media, such as polyesters such as polyethylene terephthalate (PET); polyolefins such as polyethylene and polypropylene; cellulose triacetate, Cellulose derivatives such as cellulose diacetate; polycarbonate; polyvinyl chloride; polyimide; plastics such as aromatic polyamide, polyphenylene sulfide, AI, Cu
The surface of these supports may be treated with corona discharge, radiation, ultraviolet rays, etc., or may be precoated with a suitable resin. The forms of this non-magnetic support are film, tape, sheet,
It may be in any form such as a disk, card, or drum.
また、本発明の磁気記録媒体の磁性層としては、磁性粉
末及びバインダーを主成分とし、必要に応じ、この種の
磁性層に通常含有される添加剤、例えば潤滑剤、研磨剤
、帯電防止剤、可塑剤、硬化剤、分散剤、表面処理剤等
を添加したもので、この種の磁気記録媒体の磁性層とし
て通常用いられるものを使用できる。The magnetic layer of the magnetic recording medium of the present invention contains magnetic powder and a binder as main components, and if necessary, additives normally contained in this type of magnetic layer, such as lubricants, abrasives, and antistatic agents. , a plasticizer, a curing agent, a dispersant, a surface treatment agent, etc., and which are commonly used as the magnetic layer of this type of magnetic recording medium can be used.
本発明の磁気記録媒体は、例えば次のようにして製造す
ることができる。The magnetic recording medium of the present invention can be manufactured, for example, as follows.
先ず、前記無機粉末、前記バインダー及びカーボンブラ
ックを前記の割合で配合し、更に必要に応じ各種の前記
添加剤を加えた配合物を常法により溶剤と混合してバン
クコート塗料を調製する。First, the inorganic powder, the binder, and carbon black are blended in the proportions described above, and if necessary, various of the additives mentioned above are added, and the mixture is mixed with a solvent by a conventional method to prepare a bank coat paint.
次いで、この塗料を、一方の面に磁性層の形成された前
記非磁性支持体の他方の面（裏面）に常法により乾燥膜
厚が約０．２〜２μｍになるように塗布し、塗膜を乾燥
して前記非磁性支持体の裏面にバックコート層を形成し
、本発明の磁気記録媒体を得る。Next, this paint is applied to the other side (back side) of the non-magnetic support with a magnetic layer formed on one side by a conventional method so that the dry film thickness is about 0.2 to 2 μm. The film is dried and a back coat layer is formed on the back surface of the nonmagnetic support to obtain the magnetic recording medium of the present invention.
〔実施例］
以下に本発明の実施例、比較例及び本発明の効果を示す
試験例を挙げ、本発明を更に詳細に説明する。[Example] The present invention will be explained in more detail by giving examples, comparative examples, and test examples showing the effects of the present invention.
実施例１〜１３及び比較例１，２
〔磁性層の形成］
下記塗料配合の配合物をボールミルで４８時間混合後、
混合物にコロネー）Ｌ（商品名、日本ポリウレタン工業
■製のトリメチロールプロパントリイソシアナー日２．
５重量部を添加し、更に３０分間混合を行い、磁性塗料
を調製した。この塗料を、１４μｍ厚のＰＥＴフィルム
上に乾燥膜厚が４μｍになるように塗布し、塗膜を磁場
配向処理後乾燥して、ＰＥＴフィルム上に磁性層を形成
した。次いで、磁性層の形成されたＰＥＴフィルムをロ
ールに巻き取った後、磁性層をカレンダー処理した。Examples 1 to 13 and Comparative Examples 1 and 2 [Formation of magnetic layer] After mixing the following paint composition in a ball mill for 48 hours,
Coronet) L (trade name, trimethylolpropane triisocyaner manufactured by Nippon Polyurethane Industry ■) was added to the mixture.
5 parts by weight were added and mixed for an additional 30 minutes to prepare a magnetic paint. This coating material was applied onto a PET film having a thickness of 14 .mu.m to a dry film thickness of 4 .mu.m, and the coating film was subjected to magnetic field orientation treatment and dried to form a magnetic layer on the PET film. Next, the PET film on which the magnetic layer was formed was wound up onto a roll, and then the magnetic layer was calendered.
・塗料配合
Ｃｏ ７ Ｆｅｚｅ３１００重量部レシチン
２ 〃カーボンブラックｍ′
４ “Ｃｒ２Ｏ，２〃
ＶＡＣ；Ｈ” １２ 〃ニラ
ポラン２３０４°３ １２ 〃ブチルステアレー
ト ２ 〃メチルエチルケトン
１５０ 〃トルエン ５０ 〃（
註）＊１：平均粒子径２５ｎｍ
＊２：ユニオンカーバイド社製の塩化ビニル／酢酸ビニ
ル／ポリビニルアルコ
ール共重合体
＊３：日本ポリウレタン工業■製のポリウレタン樹脂
〔バックコート層の形成］
下記バンクコ−）１料配合の配合物をボールミルで９６
時間混合後、混合物にコロネー）Ｌ２０重量部を添加し
、更に３０分間混合を行い、バックコート塗料を調製し
た。この塗料を、前記の磁性層の形成されたＰＥＴフィ
ルムの裏面に乾燥膜厚が１μｍになるように塗布し、塗
膜を乾燥して、バックコート層を形成した。・Paint formulation Co 7 Feze 3100 parts by weight lecithin
2 〃Carbon black m'
4 “Cr2O,2〃 VAC;H” 12 〃Niraporan 2304°3 12 〃Butyl stearate 2 〃Methyl ethyl ketone
150 Toluene 50 (
Note) *1: Average particle size 25 nm *2: Vinyl chloride/vinyl acetate/polyvinyl alcohol copolymer manufactured by Union Carbide *3: Polyurethane resin manufactured by Nippon Polyurethane Industries ■ [Formation of back coat layer] Bankco below) 96% of the 1-component mixture in a ball mill
After mixing for a period of time, 20 parts by weight of Coronet) L was added to the mixture, and the mixture was further mixed for 30 minutes to prepare a back coat paint. This paint was applied to the back side of the PET film on which the magnetic layer was formed so that the dry film thickness was 1 μm, and the paint film was dried to form a back coat layer.
然る後、磁性層及びバンクコートの形成されたＰＥＴフ
ィルムを２分の１インチ幅にスリントし、カセットに装
填して、ビデオカセットを作製した。Thereafter, the PET film on which the magnetic layer and bank coat were formed was slinted to a width of 1/2 inch and loaded into a cassette to produce a video cassette.
・バックコート塗料配合
カーボンブラック” ｉ ｏ ｏ重量部ニト
ロセルロース ５０ 〃ニラポラン２３０
４ ５０ 〃無機粉末（第１表及び第２表）
７ 〃レシチン ２ 〃メ
チルエチルケトン ４００ 〃トルエン
２００ 〃（註）＊ｌ：平均粒子径２５
ｎｍ
（試験例）
上記の実施例及び比較例で作製したビデオカセットそれ
ぞれについて、下記の繰返し走行テスト及び転写性促進
テストを下記の如く行った。それらの結果を下記の第１
表及び第２表に示す。・Backcoat paint blended carbon black" i o o parts by weight Nitrocellulose 50 〃Niraporan 230
4 50 Inorganic powder (Tables 1 and 2)
7 Lecithin 2 Methyl ethyl ketone 400 Toluene
200 (Note) *l: Average particle diameter 25
nm (Test Example) For each of the video cassettes produced in the above Examples and Comparative Examples, the following repeated running test and transferability acceleration test were conducted as described below. Those results are shown in the first section below.
Shown in Table and Table 2.
ビデオカセットをビデオデツキにて２００回繰返し走行
テストを行い、走行テスト前後のテープのバックコート
層の摩擦係数を下記の如く測定した。The video cassette was tested by running it repeatedly on a video deck 200 times, and the coefficient of friction of the back coat layer of the tape before and after the running test was measured as follows.
Ｐｊ擦係数（μ）の測定
■横浜システム研究所型のテープ走行試験１ＴＢＴ−３
００Ｄを用いて、テープを、５ｍｍクシリンダ−裏面が
１８０′接触する状態でテープ速度３．３ｃｍ／秒にて
走行させ、巻出側及び巻取側のテンションを測定し、次
式より摩擦係数（／７）を求めた。Measurement of Pj friction coefficient (μ) ■ Yokohama System Research Institute type tape running test 1TBT-3
Using 00D, the tape was run at a tape speed of 3.3 cm/sec with the back side of the 5 mm cylinder in contact with 180', the tension on the unwinding side and the winding side was measured, and the friction coefficient ( /7) was calculated.
ｌ ［巻出側テンション］
π 〔巻取側テンション］
〔転写性促進テスト〕
ビデオカセットを、テープを巻き取った状態で５０°Ｃ
１相対湿麿５０％下に１０日間保存し、保存前後のテー
プの磁性層の中心線平均表面粗さ（Ｒａ）をＪＩＳ Ｂ
Ｏ６０１に従って測定した。保存前のテープの磁性層の
中心線平均表面粗さ（Ｒａ）は０．０２０μｍであった
。l [Tension on unwinding side] π [Tension on winding side] [Transferability acceleration test] Heat the video cassette at 50°C with the tape wound up.
The tape was stored at a relative humidity of 50% for 10 days, and the centerline average surface roughness (Ra) of the magnetic layer of the tape before and after storage was determined according to JIS B.
Measured according to O601. The centerline average surface roughness (Ra) of the magnetic layer of the tape before storage was 0.020 μm.
第１表及び第２表に示す結果から、実施例のものは、比
較例のものに比して、繰返し走行テスト前の摩擦係数（
μ）が低く且つ繰返し走行テスト後の摩擦係数（μ）の
上昇が少なく（即ち、走行性が安定し）、また転写性促
進テストの保存後のテープの磁性層の中心線平均表面粗
さ（Ｒａ）が悪化していない（即ち、バックコート層の
磁性層への転写が生じていない）ことが判る。From the results shown in Tables 1 and 2, the friction coefficient of the example before the repeated running test (
The coefficient of friction (μ) after repeated running tests is low (in other words, the running properties are stable), and the centerline average surface roughness ( It can be seen that Ra) has not deteriorated (that is, no transfer of the back coat layer to the magnetic layer has occurred).
〔発明の効果］
本発明の磁気記録媒体は、走行性が安定し、且つバック
コート層の磁性層への転写が生じず、従って該転写によ
る磁気特性の低下が起こらないものである。[Effects of the Invention] The magnetic recording medium of the present invention has stable running properties and does not transfer the backcoat layer to the magnetic layer, so that the magnetic properties do not deteriorate due to the transfer.
特許出願人 花 王 株式会社Patent applicant: Hanao Co., Ltd.
Claims (1)
ックコート層を設けてなる磁気記録媒体において、上記
バックコート層中に、下記化合物の無機粉末群から選択
された少なくとも１種を含有させることを特徴とする磁
気記録媒体。 酸化ランタン、酸化サマリウム、酸化テルビウム、酸化
ユーロピウム、酸化イットリウム、チタン酸バリウム、
チタン酸鉛、チタン酸ジルコン酸鉛、チタン酸ジルコン
酸ランタン鉛、コーディエライト、チタン酸アルミニウ
ム及び硅酸バリウム。[Claims] A magnetic recording medium comprising a magnetic layer provided on one surface of a non-magnetic support and a back coat layer provided on the other surface, in which the back coat layer contains an inorganic powder group of the following compounds. A magnetic recording medium characterized by containing at least one selected species. Lanthanum oxide, samarium oxide, terbium oxide, europium oxide, yttrium oxide, barium titanate,
Lead titanate, lead zirconate titanate, lanthanum lead zirconate titanate, cordierite, aluminum titanate and barium silicate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63103319A JP2647129B2 (en) | 1988-04-26 | 1988-04-26 | Magnetic recording media |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63103319A JP2647129B2 (en) | 1988-04-26 | 1988-04-26 | Magnetic recording media |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9024696A Division JP2813176B2 (en) | 1997-02-07 | 1997-02-07 | Magnetic recording media |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01276424A true JPH01276424A (en) | 1989-11-07 |
| JP2647129B2 JP2647129B2 (en) | 1997-08-27 |
Family
ID=14350879
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63103319A Expired - Lifetime JP2647129B2 (en) | 1988-04-26 | 1988-04-26 | Magnetic recording media |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2647129B2 (en) |
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| Publication number | Publication date |
|---|---|
| JP2647129B2 (en) | 1997-08-27 |
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