JPS59116926A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS59116926A JPS59116926A JP57225304A JP22530482A JPS59116926A JP S59116926 A JPS59116926 A JP S59116926A JP 57225304 A JP57225304 A JP 57225304A JP 22530482 A JP22530482 A JP 22530482A JP S59116926 A JPS59116926 A JP S59116926A
- Authority
- JP
- Japan
- Prior art keywords
- metallic film
- ferromagnetic powder
- magnetic
- fine ferromagnetic
- acicular
- 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
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
- G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
- G11B5/714—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the dimension of the magnetic particles
Landscapes
- Paints Or Removers (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、磁気記録媒体に関し、特に帯電防止の改良に
関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to magnetic recording media, and more particularly to improvements in antistatic properties.
最近、磁気記録媒体、特にビデオテープでは、記録密度
の向上のため、強磁性微粉末の微粒子化、高分散化の研
究が広く行なわれている。しかしながら強磁性微粉末の
微粒子化、高分散化に伴ない、磁性層の表面電気抵抗が
高くなり、磁気記録テープが著るしく帯電しやすく、使
用とともにゴミ等の付着によシトロツブアウトが増加す
ることがわかった。Recently, in order to improve the recording density of magnetic recording media, especially video tapes, research has been widely conducted on making ferromagnetic fine powders finer and more dispersed. However, as the ferromagnetic fine powder becomes finer and more dispersed, the surface electrical resistance of the magnetic layer increases, making the magnetic recording tape significantly more likely to be charged. I found out that it does.
従来、オーディオ用、ビデオ用、コンピューター用磁気
記録テープでは、帯電防止のために導電性カーボンブラ
ックや、界面活性剤等の帯電防止剤等を磁性層に添加し
ていた。Conventionally, in magnetic recording tapes for audio, video, and computers, conductive carbon black and antistatic agents such as surfactants have been added to the magnetic layer to prevent static electricity.
しかし、カーポンプシックの添加によシ、磁性層の充填
率の低下のため電磁変換特性の劣化、磁性層の耐久性の
悪化等の弊害が生じた。寸た界面活性剤等の帯電防止剤
のを添加することにより磁気テープへのハリツキ、添加
剤のブルーミングなどが起シ、磁気テープの走行性及び
電磁変換特性が悪くなる。However, the addition of carpump sick caused problems such as deterioration of electromagnetic conversion characteristics and deterioration of the durability of the magnetic layer due to a decrease in the filling rate of the magnetic layer. Addition of a small amount of antistatic agent such as a surfactant causes hardness of the magnetic tape, blooming of the additive, etc., and deteriorates the running properties and electromagnetic characteristics of the magnetic tape.
本発明者達は、磁気テープの特性を劣化させないで再生
時のドロップアウトの増加を抑えるため、磁気テープの
帯電防止方法を鋭意研究した結果、非磁性支持体の導電
性を低くすることを見い出し、本発明に到達した。それ
故に、本発明の目的は、第1に、帯電防止された磁気記
録媒体を提供するにあシ、第λに、ドロップアウトの増
加を抑えだ磁気記録媒体を提供するにある。In order to suppress the increase in dropouts during playback without deteriorating the characteristics of the magnetic tape, the inventors of the present invention have conducted intensive research on methods for preventing static electricity on magnetic tapes, and have discovered that the conductivity of the non-magnetic support can be lowered. , arrived at the present invention. SUMMARY OF THE INVENTION Therefore, the objects of the present invention are, firstly, to provide a magnetic recording medium that is prevented from charging, and secondly, to provide a magnetic recording medium that suppresses an increase in dropout.
本発明の目的は、表面に導電性の金属薄膜を設けた非磁
性支持体上に、強磁性微粉末を結合剤中に分散してなる
磁性層を設けることによって達成される。The object of the present invention is achieved by providing a magnetic layer comprising fine ferromagnetic powder dispersed in a binder on a non-magnetic support having a conductive metal thin film on its surface.
本発明に使用される非磁性支持体としては、ポリエチレ
ンテレフタレート、ポリエチレンーコ。Examples of the nonmagnetic support used in the present invention include polyethylene terephthalate and polyethylene copolymer.
t−ナフタレート、ポリブチレンテレフタレート、ポリ
ブチレンナフタレート等のポリエステル類、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、ポリ塩化ビニル、ポリ塩化ビニリデン等のビ
ニル系樹脂、ポリイミド、ポリアミドイミド、・ボリカ
ーボ゛ネート等の有機高分子フィルムが使用される。Polyesters such as t-naphthalate, polybutylene terephthalate, and polybutylene naphthalate, cellulose derivatives such as cellulose triacetate and cellulose diacetate, vinyl resins such as polyvinyl chloride and polyvinylidene chloride, polyimide, polyamideimide, and polycarbonate. Organic polymer films such as
本発明においては、上述堕有憬高分子フィルム上に、真
空蒸着、ス/ξツタリング、メッキ、イオンブレーティ
ング、ラミネート等の方法により金属薄膜を設けること
が出来る。In the present invention, a metal thin film can be provided on the above-mentioned fallen polymer film by methods such as vacuum evaporation, sputtering, plating, ion blasting, and lamination.
本発明に使用される導電性金属薄膜は非磁性であシ、具
体的には、
(1)AI!+Cu 、Zn 、Ti 、Mn 、Fe
、CO+Ni、Af、Auを主体とする金属又はこれ
らの合金、
(21(1)の金属又は合金に微量成分として、C15
i +Ni 、P、B*V*8*O又はこれらの混合物
を加えた金属または合金、
<3)/I/Iステンレス銅(J’eljNi、/Jチ
(r)、オーステナイト系ステンレス銅、などがある。The conductive metal thin film used in the present invention is non-magnetic, and specifically: (1) AI! +Cu, Zn, Ti, Mn, Fe
, CO + metals mainly consisting of Ni, Af, Au, or alloys thereof, (C15 as a trace component in the metals or alloys of 21 (1)
i + Ni, P, B*V*8*O, or a metal or alloy with the addition of a mixture thereof, <3)/I/I stainless copper (J'eljNi, /Jchi(r), austenitic stainless steel copper, etc.) There is.
性能及び使いやすさの点からはAl。From the point of view of performance and ease of use, Al is preferred.
Znが特に好ましい。Zn is particularly preferred.
また、有機高分子フィルム上に設ける金属薄膜の厚さは
、!O〜7000A、特に100〜10(7Aが好まし
い。電導性は、金属薄膜の厚さに関係し、暗い方が好ま
しいく、薄すぎると効果がない。厚い方が好ましいが、
1oooA以上厚くする効果は小さく、また、コスト的
に高くなシネ利である。Also, the thickness of the metal thin film provided on the organic polymer film is! O to 7000A, especially 100 to 10 (7A is preferable.The conductivity is related to the thickness of the metal thin film, the darker the better, and if it is too thin there will be no effect.The thicker the better,
The effect of increasing the thickness by 1 oooA or more is small, and the cost is high.
本発明に使用される強磁性微粉末としては、r−Fe2
O2、co含有r−Fe203、F e 304 L
o含有Fe3O4、Cr 02、FCzCoXNi等を
主成分とする合金等公知の強磁性微粉末がるるが、粉末
の長軸の長さがOl、2μm未満になると特に表面電気
抵抗が増し、ドロップアウトの増加が著るしくなる。こ
れらのθ、−2μm未満の強磁性微粉末は、本発明の金
属薄膜を設けた非磁性支持体と組合せることによシ、ド
ロップアウトの増加を抑えることが可能であシ、著るし
い効果が得られる。強磁性微粉末はそれ自体が針状であ
ってもよく、或いは針状でない強磁性微粉末(たとえば
、球状)が連釦した針状でもよい。The ferromagnetic fine powder used in the present invention includes r-Fe2
O2, co-containing r-Fe203, Fe304 L
There are known fine ferromagnetic powders such as alloys mainly containing o-containing Fe3O4, Cr02, FCzCoXNi, etc., but when the length of the long axis of the powder becomes less than 2 μm, the surface electrical resistance increases and dropout occurs. The increase becomes significant. By combining these ferromagnetic fine powders with θ of less than -2 μm with the non-magnetic support provided with the metal thin film of the present invention, it is possible to suppress the increase in dropout, which is significant. Effects can be obtained. The ferromagnetic fine powder itself may be acicular, or may be acicular with non-acicular ferromagnetic fine powder (for example, spherical) linked together.
強磁性微粉末の針状比(長さ/巾)の比は一般には//
/〜、20/I程度である。The acicular ratio (length/width) of ferromagnetic fine powder is generally //
/~, about 20/I.
本発明に用いれる結合剤としては従来公知の熱可塑性樹
脂、熱硬化性樹脂又は反応型樹脂やこれらの混合物があ
り、例えば、ポリエステル樹脂、セルロース糸樹脂、ポ
リウレタン樹脂、フェノール樹脂、エポキシ樹脂、ポリ
アミド樹脂或いは(メタ)アクリル酸エステル、スキレ
ン、アクリロニトリル、フタジエン、ビニルエステノヘ
塩化ビニル、塩化ビニリデン、アクリルアミド等の単
独重合体或いは共重合体がある。Binders used in the present invention include conventionally known thermoplastic resins, thermosetting resins, reactive resins, and mixtures thereof, such as polyester resins, cellulose thread resins, polyurethane resins, phenolic resins, epoxy resins, and polyamides. Examples include homopolymers and copolymers of resins, (meth)acrylic acid esters, skillene, acrylonitrile, phthadiene, vinyl ester, vinyl chloride, vinylidene chloride, acrylamide, and the like.
また、熱硬化性樹脂としては、ポリインシアネート化合
物、ポリエポキシ樹脂等がある。Furthermore, examples of thermosetting resins include polyincyanate compounds and polyepoxy resins.
強磁性微粉末と結合剤との混合比は、粉末10O重量部
に対し、g〜、25重量部である。The mixing ratio of the ferromagnetic fine powder and the binder is 25 g to 25 parts by weight per 100 parts by weight of the powder.
磁性層は、前記のバインダー、強磁性微粉末の他に更に
、1従来知られた分散剤、潤滑剤、研磨剤等の添力p斉
1」を含んでもよい。In addition to the binder and ferromagnetic fine powder described above, the magnetic layer may also contain additives such as conventionally known dispersants, lubricants, abrasives, and the like.
磁性層の形成は上記の組成で有機溶媒vc@解し、従来
の方法で分散後、塗布溶液として支持体上に塗布する。The magnetic layer is formed by dissolving the above-mentioned composition in an organic solvent, dispersing it by a conventional method, and then coating it on a support as a coating solution.
支持体上へ前記の磁気記録層を塗布する方法としてはエ
アードクターコート、ブレードコート、エアナイフコー
ト、スクイズコート、含浸コート、リバースロールコー
ト、トランスファーロールコート、グラビヤコート、キ
スコート、キャストコート、スプレィコート等が利用で
hlその他の方法も可能であり、これらの具体的説明は
朝食書店発行の1コーテイング工学」2!3頁〜277
頁(昭和4tt、jl、20発行)に詳細に記載されて
いる。Methods for applying the magnetic recording layer onto the support include air doctor coating, blade coating, air knife coating, squeeze coating, impregnation coating, reverse roll coating, transfer roll coating, gravure coating, kiss coating, cast coating, and spray coating. HL and other methods are also possible, and detailed explanations of these methods can be found in ``1 Coating Engineering'' published by Shokusen Shoten, pp. 2!3-277.
It is described in detail on page (Showa 4TT, JL, 20th issue).
支持体上に塗布された磁性層には、S/へ等の磁気特性
を高めるために平滑化処理(たとえば乾燥前のスムーズ
ニング処理又は乾燥後のカレンダリング処理)が施され
てもよい。The magnetic layer coated on the support may be subjected to a smoothing treatment (for example, a smoothing treatment before drying or a calendering treatment after drying) to enhance the magnetic properties such as S/.
以下、本発明を実施例によって具体的に説明する。実施
例及び比較例において1部」は1重量部」を示す。Hereinafter, the present invention will be specifically explained with reference to Examples. In Examples and Comparative Examples, 1 part means 1 part by weight.
実施例 1
第1図に示す巻取り式蒸着装置を用いて厚さ/≠μmの
ポリエステルフィルム上に約30OAのAJ金属膜を形
成した。Example 1 An AJ metal film of approximately 30 OA was formed on a polyester film having a thickness of /≠μm using a winding type vapor deposition apparatus shown in FIG.
蒸発源として抵抗加熱蒸発源を用い、ウェブを円筒状ド
ンムに浴って移動させながら連続的に蒸着を行ない、膜
厚は光学モニターで光学濃度を検出しながらコントロー
ルした。A resistance heating evaporation source was used as the evaporation source, and the web was continuously deposited while being moved around a cylindrical dome, and the film thickness was controlled by detecting the optical density with an optical monitor.
Co含有γF e 203 3001(1(粒
子長o、irμm)
マレイン酸変性塩化ビニル−酢酸
ビニル共重合体(’[J、C,C,社製1−VMCH,
J) 3部部ポリウレタン樹脂(グツ
ドリッチ社製
[ニステン370/J) 20部ジメチルポ
リシロキサン(D、p、=、40+ J部酢酸ブ
チル 4too部メチルエチルケ
トン 200部粒子サイズの異なる強磁
性微粉末を用いた上記組成物をボールミルで光分混線分
散後1.2j部のトリイソシアネート化合物の7部wt
%酢酸エチル溶液を加え7時間高剪断分散[7て磁性塗
布液を調整した。Co-containing γF e 203 3001 (1 (particle length o, ir μm) Maleic acid-modified vinyl chloride-vinyl acetate copolymer ('[J, C, C, 1-VMCH,
J) 3 parts polyurethane resin (manufactured by Gutdrich [Nisten 370/J) 20 parts dimethylpolysiloxane (D, p, =, 40 + J part Butyl acetate 4 too parts Methyl ethyl ketone 200 parts Ferromagnetic fine powders with different particle sizes were used After optically cross-dispersing the above composition in a ball mill, 1.2j parts of the triisocyanate compound were added to 7 parts wt.
% ethyl acetate solution and high shear dispersion for 7 hours [7] to prepare a magnetic coating solution.
得られた塗布液を前述のAJ金属薄膜を形成したポリエ
ステルフィルム上に乾燥後≠μmになるように塗布、磁
場配向処理し、乾燥後カレンダー処理し、裁断して磁気
テープを作成した。The resulting coating solution was coated onto the polyester film on which the AJ metal thin film described above was formed so that after drying it was ≠ μm, subjected to magnetic field orientation treatment, dried, calendered, and cut to prepare a magnetic tape.
比較例 I
AJ金属薄膜を設けてないポリエステルフィルムを用い
た以外は実施例/と同様の操作を行ない磁気テープを作
成した。Comparative Example I A magnetic tape was prepared in the same manner as in Example except that a polyester film without the AJ metal thin film was used.
比較例 2
実施例/の組成物に、さらにカーボンブラック(東海カ
ーボンc株)社製「ジースト、t)IJ)15部を加え
、AI!金属薄膜を形成していないポリエステルフィル
ムを用いた以外は、実施例/と同様の操作を行ない磁気
テープを作成した。Comparative Example 2 15 parts of carbon black (“Geest, t) IJ” manufactured by Tokai Carbon C Co., Ltd.) was further added to the composition of Example 2, and AI! Except that a polyester film on which no metal thin film was formed was used. A magnetic tape was prepared by performing the same operations as in Example.
実施例 2
Ni含含有−Fe粉末 3θθ部(粒子長0
072μm)
マレイン酸変性塩化ビニル酢酸
ビニル共重合体ITJ3.C,,C0社製rVMcH1
) 30部ポリウレタン樹脂(グツド
リッチ社製
「ニステンj701J) 20部ジメチル
ポリシロキサンCD、P、、=tO) を部酢酸ブチ
ル 6oo部メチルエチルクト
7 300部上記組成物を、実施例/でA
J金属薄膜を形成したポリエステルフィルム上に実施例
/と同様の操作をして磁気テープを作成した。Example 2 Ni-containing -Fe powder 3θθ part (particle length 0
072 μm) Maleic acid modified vinyl chloride vinyl acetate copolymer ITJ3. C,, rVMcH1 manufactured by C0
) 30 parts polyurethane resin (Nysten J701J, manufactured by Gutdrich) 20 parts dimethylpolysiloxane CD, P, = tO) 60 parts butyl acetate 60 parts methyl ethyl chloride 7 300 parts The above composition was used in Examples/A
A magnetic tape was prepared in the same manner as in Example 1 on a polyester film on which a J metal thin film was formed.
比較例 3
A7金属薄膜を設けていないポリエステルフィルムを用
いた以外は、実施例λと同様の操作を行ない磁気テープ
を作成した。Comparative Example 3 A magnetic tape was prepared in the same manner as in Example λ, except that a polyester film without an A7 metal thin film was used.
比較例 4
実施例コの組成物に、さらにカーボンブラック(東海カ
ーボン(株)社製「ジーストjHJ)/!部を加え、A
l金属薄膜を設けてないポリエステルフィルムを用いた
以外は、実施例λと同様の操作を行ない磁気テープを作
成した。Comparative Example 4 To the composition of Example A, 1 part of carbon black (Geest jHJ manufactured by Tokai Carbon Co., Ltd.) was further added, and A
A magnetic tape was prepared in the same manner as in Example λ, except that a polyester film without a metal thin film was used.
上記実施例、比較例からイリた磁気テープの表面電気抵
抗及びビデオ出力を測定した。The surface electrical resistance and video output of the magnetic tapes used in the above Examples and Comparative Examples were measured.
表面電気抵抗は、超絶縁抵抗計(タケダ理研工業(株)
社製rTR−ざ6//A」)を用いて測定した。Surface electrical resistance was measured using a super insulation resistance meter (Takeda Riken Kogyo Co., Ltd.)
The measurements were made using a commercially available rTR-za6//A''.
ビデオ出力は、V)1.S方式VTRr松下電器製rN
V−ざroo」)を用い、実施例λ、比較例3〜≠につ
いては、記録再住ヘッドをセンダスト合金ヘッドに改造
したVTRを用いて、4部MHzの再生出力(比較例/
のテープをOdBとした)を測定した。The video output is V)1. S-type VTRr Matsushita Electric rN
For Example λ and Comparative Examples 3 to ≠, the reproduction output of 4 MHz (Comparative Example/
The tape was measured as OdB).
表/よシ本発明の金属薄膜を設けたポリエステルフィル
ムを用いることによシ、導電性のカーボ゛ンブラックを
用いた時のような電磁変換特性の悪化を起こすことなく
、電気抵抗を下げることが(き、帯電の防止に効果があ
ることがわかる。Table: By using the polyester film provided with the metal thin film of the present invention, it is possible to lower the electrical resistance without causing deterioration of electromagnetic conversion characteristics unlike when using conductive carbon black. It can be seen that it is effective in preventing static electricity.
実施例 3
実施例λにおいて、粒子長0,72μmのNi含含有−
Fe粉末の代わシに、粒子長の異なるNi含含有−Fe
粉末(O,/ z 〜o 、!;pm)を用いた以外は
実施例コと同様の操作を行ない磁気テープを作成した。Example 3 In Example λ, Ni-containing particles with a particle length of 0.72 μm
Instead of Fe powder, Ni-containing -Fe powder with different particle lengths is used.
A magnetic tape was prepared in the same manner as in Example 1 except that powder (O,/z~o,!; pm) was used.
比較例 5
実施例3において、AI!金属薄膜を設けたポリエステ
ルフィルムの代わシに、AI!金属薄膜を設けてないポ
リエステルフィルムを用いた以外は、実施例3と同様の
操作を行ない磁気テープを作成した。Comparative Example 5 In Example 3, AI! Instead of polyester film with metal thin film, AI! A magnetic tape was produced in the same manner as in Example 3, except that a polyester film without a metal thin film was used.
実施例3.Jで作成した磁気テープの100回走行後の
ドロップアウト(/夕μ5ec)をドロップアウトカウ
ンターで測定した。粒子長とドロップアウトの増加率の
関係を第2図に示す。Example 3. After running the magnetic tape 100 times, the dropout (/μ5ec) was measured using a dropout counter. Figure 2 shows the relationship between particle length and dropout increase rate.
第2図から、本発明の金属薄膜を設けたポリエステルフ
ィルムを用いることによシ、特に0.2μm未満の粒子
長の強磁性粉末を用いた時のドロップアウトの増加を抑
えることができる。From FIG. 2, by using the polyester film provided with the metal thin film of the present invention, it is possible to suppress an increase in dropout, especially when using ferromagnetic powder with a particle length of less than 0.2 μm.
第1図は非磁性支持体上に導電性金属薄膜を設けるため
の巻取式蒸着装置である。第1図において/は送出ロー
ル、コは巻取ロール、3はウェブ、≠はシャッター、!
は抵抗加熱蒸発源、乙は円筒状ドラム、7は光学モニタ
ーを示す。
第2図は粒子長とドロップアウト増加量の関係を示すグ
27である。FIG. 1 shows a winding type vapor deposition apparatus for forming a conductive metal thin film on a non-magnetic support. In Fig. 1, / is a delivery roll, ko is a take-up roll, 3 is a web, ≠ is a shutter, !
1 shows a resistance heating evaporation source, 2 shows a cylindrical drum, and 7 shows an optical monitor. FIG. 2 is a diagram 27 showing the relationship between particle length and increase in dropout.
Claims (1)
を設けてなシ、該磁性層は長軸の長さがOo、2μ未満
の針状強磁性微粉末を含有することを特徴とする磁気記
録媒体。A magnetic layer is provided on a non-magnetic support having a conductive metal thin film on the surface, and the magnetic layer contains acicular ferromagnetic fine powder with a major axis length of Oo and less than 2μ. magnetic recording media.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP57225304A JPS59116926A (en) | 1982-12-22 | 1982-12-22 | Magnetic recording medium |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP57225304A JPS59116926A (en) | 1982-12-22 | 1982-12-22 | Magnetic recording medium |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS59116926A true JPS59116926A (en) | 1984-07-06 |
JPH0442727B2 JPH0442727B2 (en) | 1992-07-14 |
Family
ID=16827241
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP57225304A Granted JPS59116926A (en) | 1982-12-22 | 1982-12-22 | Magnetic recording medium |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS59116926A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5456734A (en) * | 1993-05-07 | 1995-10-10 | Fuji Photo Film Co., Ltd. | Abrasive member |
US5573444A (en) * | 1993-06-22 | 1996-11-12 | Fuji Photo Film Co., Ltd. | Polishing method |
US5695386A (en) * | 1993-08-10 | 1997-12-09 | Fuji Photo Film Co., Ltd. | Cleaning method using abrasive tape |
-
1982
- 1982-12-22 JP JP57225304A patent/JPS59116926A/en active Granted
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5456734A (en) * | 1993-05-07 | 1995-10-10 | Fuji Photo Film Co., Ltd. | Abrasive member |
US5573444A (en) * | 1993-06-22 | 1996-11-12 | Fuji Photo Film Co., Ltd. | Polishing method |
US5695386A (en) * | 1993-08-10 | 1997-12-09 | Fuji Photo Film Co., Ltd. | Cleaning method using abrasive tape |
Also Published As
Publication number | Publication date |
---|---|
JPH0442727B2 (en) | 1992-07-14 |
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