KR20030046755A - Magnetic recording medium - Google Patents
Magnetic recording medium Download PDFInfo
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- KR20030046755A KR20030046755A KR1020010077000A KR20010077000A KR20030046755A KR 20030046755 A KR20030046755 A KR 20030046755A KR 1020010077000 A KR1020010077000 A KR 1020010077000A KR 20010077000 A KR20010077000 A KR 20010077000A KR 20030046755 A KR20030046755 A KR 20030046755A
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- magnetic
- recording medium
- magnetic recording
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- 230000005291 magnetic effect Effects 0.000 title claims abstract description 53
- 239000000843 powder Substances 0.000 claims abstract description 20
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 15
- 239000010941 cobalt Substances 0.000 claims abstract description 15
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 15
- 230000005415 magnetization Effects 0.000 claims abstract description 11
- 239000003973 paint Substances 0.000 claims abstract description 4
- 230000005294 ferromagnetic effect Effects 0.000 claims description 17
- 229920006395 saturated elastomer Polymers 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 11
- 238000006243 chemical reaction Methods 0.000 description 9
- 239000011248 coating agent Substances 0.000 description 9
- 238000000576 coating method Methods 0.000 description 9
- 238000000034 method Methods 0.000 description 6
- 239000002245 particle Substances 0.000 description 6
- 239000006247 magnetic powder Substances 0.000 description 5
- 238000001035 drying Methods 0.000 description 4
- 238000004381 surface treatment Methods 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 239000006229 carbon black Substances 0.000 description 3
- 238000009499 grossing Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000011230 binding agent Substances 0.000 description 2
- 238000001723 curing Methods 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 235000014113 dietary fatty acids Nutrition 0.000 description 2
- 229930195729 fatty acid Natural products 0.000 description 2
- 239000000194 fatty acid Substances 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- -1 Fatty acid ester Chemical class 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical compound [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 238000003490 calendering Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920006290 polyethylene naphthalate film Polymers 0.000 description 1
- 239000004848 polyfunctional curative Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
Classifications
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- 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
- G11B5/64—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent
- G11B5/65—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition
- G11B5/656—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition containing Co
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S428/00—Stock material or miscellaneous articles
- Y10S428/90—Magnetic feature
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- Magnetic Record Carriers (AREA)
Abstract
Description
본 발명은 자기기록매체에 관한 것으로서, 보다 구체적으로는 특정 강자성 분말을 사용하여 오디오특성을 향상시킨 자기기록매체에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium, and more particularly to a magnetic recording medium having improved audio characteristics by using a specific ferromagnetic powder.
종래 오디오 테이프, 비디오 테이프 등의 자기 테이프 및 플로피디스크 등의 자기디스크 등으로 된 자기 기록 매체의 제조방법은 통상의 제품보다도 넓은 영역을 가지는 비자성 지지체상에 자성도포액을 도포해서 자성층을 형성하고, 배향 처리등을 하여 건조한 후 상기 자성층을 표면 평활화 처리하여 자기 기록 매체의 원판을 만든다. 그후 경화 공정을 거친 다음 사용의 목적에 맞는 일정한 폭으로 절단하기 위하여 슬릿팅공정을 거쳐 최종의 제품을 완성하게 된다. 최종의 공정으로 카세팅 등의 공정을 거쳐서 다음 단계의 최종제품인 카세트를 만들수도 있다.Conventionally, a method of manufacturing a magnetic recording medium made of magnetic tape such as audio tape or video tape and magnetic disk such as floppy disk is applied to form a magnetic layer by applying a magnetic coating liquid on a nonmagnetic support having a larger area than a conventional product. After drying by performing an orientation treatment or the like, the magnetic layer is subjected to surface smoothing to make an original of a magnetic recording medium. After the hardening process, the slitting process is completed to cut the product to a certain width suitable for the purpose of use. As a final process, a cassette, which is the final product of the next stage, may be produced by a process such as casing.
상기 자성 도포액의 제조는 자성 분말, 특히 일반 마그네타이트를 사용하여 알루미나 카이본 블랙 등의 기타 무기물 및 윤활제, 경화제 분산제 등을 결합제 용액에 분산하여 제조하고, 상기 표면 평활화 처리는 자성층 표면의 평활화 및 층진밀도 등을 향상시키고, 도포 두께의 균일화등을 달성 할 수 있다.The magnetic coating solution is prepared by dispersing other inorganic materials such as alumina carbon black and other lubricants, hardener dispersants and the like in a binder solution using magnetic powder, in particular general magnetite, and the surface smoothing treatment is performed to smooth and layer the surface of the magnetic layer. It is possible to improve the density and the like, and to achieve uniform coating thickness.
종래, 강자성 분말로 Si 단독 또는 Si/Zn 표면처리되고 보자력이 620-700 Oe, 포화자화값이 80-84 emu/g인 코발트 마그네타이트를 사용하여 왔으나, 이러한 강자성 분말을 사용하게 되면 전자 변환 특성중 오디오특성(음성 기록과 관련된 특성)이 저하되는 문제점이 있다. 즉, 오디오 출력의 레벨 변동으로서 출력의 레벨이 20㎐∼20㎑ 전폭에 걸쳐 불균일하게 나타나 비디오 녹화 재생시 오디오의 음폭이 불균일하게 된다.Conventionally, cobalt magnetite having Si alone or Si / Zn surface treatment and coercivity of 620-700 Oe and saturation magnetization of 80-84 emu / g has been used as a ferromagnetic powder. There is a problem that audio characteristics (characteristics related to voice recording) are degraded. In other words, as the level variation of the audio output, the output level is uneven over the entire width of 20 Hz to 20 Hz, resulting in an uneven sound width of the audio during video recording and reproduction.
따라서 본 발명은 자기기록매체의 오디오(음성) 특성을 향상시키는 것을 목적으로 한다.Accordingly, an object of the present invention is to improve the audio (voice) characteristics of a magnetic recording medium.
상기한 목적을 달성하기 위한 본 발명자의 연구에서 마그네타이트 자성 분말을 사용하여 제조한 자성도료를 비자성지지체 상에 형성할 경우 입자 Size가 작거나 보자력이 700 Oe 이하이거나 포화자화가 84emu/g이하인 경우는 자기 기록 매체의 화면의 전자 변환 특성은 우수하지만 주파수 영역이 낮은 오디오 영역의 특성은 매우 저하되는 결과를 나타내나, 자성층이 비표면적 30∼32㎡/g, 보자력 700-710 Oe, 포화자화(σs값) 84 이상인 Si/Al 표면처리된 코발트 마그네타이트를 강자성 분말로 함유하는 경우 전자 변환 특성이 우수하면서도 주파수 전 영역에서 오디오 영역의 특성이 일층 향상된다는 사실을 알게되어 본 발명을 완성하게 된 것이다.When the magnetic coating prepared by using the magnetite magnetic powder is formed on the nonmagnetic support in the study of the present inventors for achieving the above object, the particle size is small, the coercive force is 700 Oe or less, or the saturation magnetization is 84 emu / g or less. The results show that the characteristics of the audio region of the magnetic recording medium are excellent, but the characteristics of the audio region having a low frequency range are very low. However, the magnetic layer has a specific surface area of 30 to 32 m 2 / g, coercive force 700 to 710 Oe, and saturation magnetization ( When the Si / Al surface-treated cobalt magnetite having a sigma value of 84 or more is contained as a ferromagnetic powder, the present invention has been found to have excellent electron conversion characteristics and to further improve the characteristics of the audio region in the entire frequency range.
그러므로 본 발명에 의하면, 비자성 지지체 상에 강자성 분말을 함유하는 자성 도료를 도포하여 형성시킨 자성층을 갖는 자기 기록 매체에 있어서, 상기 강자성 분말로서 비표면적 30∼32㎡/g, 보자력 700-710 Oe, 포화자화(σs값) 84 emu/g 이상인 Si/Al 표면처리된 코발트 마그네타이트를 함유하는 것을 특징으로 하는 자기기록 매체가 제공된다.Therefore, according to the present invention, in a magnetic recording medium having a magnetic layer formed by applying a magnetic coating containing ferromagnetic powder on a nonmagnetic support, the ferromagnetic powder has a specific surface area of 30 to 32 m 2 / g and coercive force 700-710 Oe. And a magnetic recording medium containing Si / Al surface treated cobalt magnetite having a saturation magnetization (? S value) of 84 emu / g or more.
이하, 본 발명을 보다 상세하게 설명하기로 한다.Hereinafter, the present invention will be described in more detail.
통상적으로 자기기록매체는 강자성 분말, 카아본 블랙, 연마제 등을 결합제 용액에 분산시켜 자성 도료로 만들고, 이러한 자성도료를 비자성 지지체 상에 일정 부피로 도포하여 자성층을 형성시키고, 건조, 평활화, 경화 및 제단 공정을 거쳐 자기기록 매체를 제조하게 된다. 이러한 자기기록매체의 제조에서 강자성 분말의 특성이 중요하고, 또한 비자성 지지체에 자성 밀도가 고루고루 분포되어야 하고 도포면이 평활하게 되도록 도포하는 것도 중요하다.In general, the magnetic recording medium is made of a magnetic coating by dispersing ferromagnetic powder, carbon black, abrasive, etc. in a binder solution, and applying the magnetic coating in a predetermined volume on a nonmagnetic support to form a magnetic layer, and drying, smoothing and curing. And through the cutting step, a magnetic recording medium is produced. In the production of such a magnetic recording medium, the characteristics of the ferromagnetic powder are important, and it is also important to apply the magnetic density to the nonmagnetic support evenly and to apply the coating surface smoothly.
본 발명에 의하면 자기기록매체의 자성층에 함유되는 강자성 분말로 코발트 마그네타이트가 사용된다. 강자성 분말로 사용되어지는 코발트 마그네타이트는 자기기록 매체에 있어서 가장 중요한 주원료로서 비디오 테이프의 전자 변환 특성을 향상시키고 주행특성 등의 물리적인 특성을 향상시키기 위하여 사용되어 지는데, 자기기록 매체에 있어서 국부적인 자화 반전 목적으로 자기기록에 관하여는 자성층의 충전 밀도에 따라, 자성 분말의 처리 상태에 따라 달라지게 되므로 자성 분말의 주요 항목의 특성, 예를 들어 보자력, 비표면적, 표면처리, 포화자화, pH 등을 요구하게 된다.According to the present invention, cobalt magnetite is used as the ferromagnetic powder contained in the magnetic layer of the magnetic recording medium. Cobalt magnetite, which is used as ferromagnetic powder, is the most important raw material for magnetic recording media. It is used to improve the electronic conversion characteristics of video tapes and physical properties such as driving characteristics. As for the magnetic recording for the purpose of reversal, depending on the packing density of the magnetic layer and the processing state of the magnetic powder, the characteristics of the main items of the magnetic powder, for example, coercivity, specific surface area, surface treatment, saturation magnetization, pH, etc. You will be asked.
특히, 전자 변환 특성이 우수하면서 주파수 전 영역에서 오디오 영역의 특성이 우수한 자기기록 매체의 제조와 공정에 적용하기 위하여는 자기 특성에 가장 많은 영향을 미치는 자성체의 특성을 고려하여 선택하는 것이 중요하다.In particular, it is important to consider the characteristics of the magnetic material that has the greatest influence on the magnetic properties in order to be applied to the manufacturing and processing of the magnetic recording medium having excellent electronic conversion characteristics and excellent audio characteristics in the entire frequency range.
본 발명에 의하면 강자성 분말로 입자 크기가 비표면적 30∼32㎡/g로 크고, 보자력이 700∼710Oe이고 포화자화가 84emu/g 이상인 Si/Al 표면처리된 코발트 마그네타이트가 사용된다.According to the present invention, cobalt magnetite with Si / Al surface treatment having a large particle size of 30 to 32 m 2 / g, a coercive force of 700 to 710Oe, and a saturation magnetization of 84 emu / g or more is used as a ferromagnetic powder.
자성체의 입자 크기는 상기의 고주파와 저주파 영역의 기록 재생에 있어서 매우 중요한 역할을 수행한다. 입자 크기는 단독의 입도 분포 보다 포괄적인 비표면적으로 측정하여 크기를 추정한다.The particle size of the magnetic body plays a very important role in the recording and reproduction of the high frequency and low frequency regions. The particle size is estimated by measuring the specific surface area more comprehensive than the particle size distribution alone.
특히, Si/Al 표면처리된 코발트 마그네타이트는 Si 함량이 1.1∼1.2중량%이고, Al 함량이 0.12∼0.14중량%인 것이 바람직하다.In particular, the Si / Al surface-treated cobalt magnetite preferably has a Si content of 1.1 to 1.2% by weight and an Al content of 0.12 to 0.14% by weight.
입자 크기가 비표면적 30∼32㎡/g로 크고, 보자력이 700∼710Oe이고 포화자화가 84emu/g 이상인 Si/Al 표면처리된 코발트 마그네타이트는 후술하는 실험결과로부터 명백하게 되는 바와 같이 고주파 영역의 화상 신호 기록은 기존의 자성 분말을 사용한 도료와 비슷하게 나타나지만 음성 기록과 관련된 특성은 아주 우수한 결과를 나타낸다. 특히 오디오(음성)과 RF출력(화상기록)의 주파수 전 영역에서 우수한 기록 재생 특성을 가진다.Si / Al surface-treated cobalt magnetite having a large particle size of 30 to 32 m2 / g, a coercive force of 700 to 710 Oe, and a saturation magnetization of 84 emu / g or more, as is apparent from the experimental results described later, an image signal in a high frequency region Recordings appear similar to paints using conventional magnetic powders, but the characteristics associated with voice recordings yield very good results. In particular, it has excellent recording and reproducing characteristics in the entire frequency range of audio (audio) and RF output (image recording).
이상 설명한 바와 같은 본 발명의 특징 및 기타의 장점은 후술되는 실시예로부터 보다 명백하게 될 것이다. 단, 본 발명은 하기 실시예로 제한되는 것은 아니다.Features and other advantages of the present invention as described above will become more apparent from the following examples. However, the present invention is not limited to the following examples.
하기 실시예 및 비교예에서 제시되는 전자변환특성(RF-출력, Audio 특성) 및 드롭아웃은 다음과 같이 측정한 것이다.Electronic conversion characteristics (RF-output, Audio characteristics) and dropouts shown in the following Examples and Comparative Examples are measured as follows.
<전자변환특성> 오실로스코프로 병행하여 측정<Electronic conversion characteristics> Measured in parallel with an oscilloscope
1) RF-출력: 기준비데오테이프를 일본빅터사의 비데오테크(BR-7000)에 장착하여 100% 백색신호를 기록한 다음 재생시의 출력을 측정하고, 비교예 1에서 얻어진 비데오테이프의 RF-출력을 0dB로 정하고, 이 값을 기준으로 하여 그 차이를 나타내었다.1) RF-output: A standard video tape is mounted on a video technology (BR-7000) of Japan Victor Co., Ltd. to record a 100% white signal, and then measure the output at the time of reproduction.The RF-output of the video tape obtained in Comparative Example 1 is 0 dB. The difference was shown based on this value.
2) 오디오(Audio) 특성 : 음성입력단자에 기준입력신호 레벨(level) 보다 -10dB 떨어진 신호를 인가하여 음성출력단자에 나타나는 1KHz 재생출력 레벨과 7KHz 재생출력레벨과의 차이를 평가하였다(+/- 3dB).2) Audio characteristic: The difference between the 1KHz playback output level and 7KHz playback output level that appears at the audio output terminal was evaluated by applying a signal -10dB away from the reference input signal level to the audio input terminal (+ / -3 dB).
<드롭아웃><Dropout>
비데오테이프에 5단계 단차신호를 최적기록전류로 기록한 다음, 재생때의 비데오 앰프의 감쇄량이 20유, 지속시간이 15μsec 이상인 것을 드롭아웃으로 간주하고, 10분 동안 계속측정한 후, 1분당의 개수로 평균하여 나타내었다.After recording the 5-step difference signal on the video tape with the optimal recording current, the attenuation of the video amplifier during playback is 20 drops and the duration is 15 μsec or more. The average is shown.
[실시예 1]Example 1
두께 9.5㎛의 폴리에틸렌나프탈레이트 필름의 표면에 강자성분말로 비표면적 31㎡/g, 보자력 703 Oe, 포화자화(σs값) 84.7 emu/g인 Si/Al 표면처리된 코발트 마그네타이트를 사용하여 아래에 기재한 조성 및 방법으로 제조한 자성도료를 두께 2.5㎛로 도포하고, 배향, 건조후 캘린더링하여 2.0㎛의 자성층막을 형성하였다.이어서 필름의 이면에 1㎛의 백코트층을 형성시키고 배향, 건조 및 캘린더링하여 두께 12.5㎛의 원반형 자기기록매체를 제조하였다.The surface of a polyethylene naphthalate film having a thickness of 9.5 μm was described below using a Si / Al surface-treated cobalt magnetite having a specific surface area of 31 m 2 / g, coercive force 703 Oe, and saturation magnetization (σ s) of 84.7 emu / g. A magnetic coating prepared by one composition and method was applied to a thickness of 2.5 μm, and then calcined by orientation and drying to form a 2.0 μm magnetic layer film. Then, a 1 μm backcoat layer was formed on the back surface of the film, and the alignment, drying and calendering were performed. Ring was used to make a disc shaped magnetic recording medium having a thickness of 12.5 μm.
제조된 자기기록매체의 전자변환특성을 실험한 결과, RF 출력 +1.1, 오디오 +1.1이었고, 드롭아웃은 4 이었다.As a result of experiment on the electronic conversion characteristics of the manufactured magnetic recording media, the RF output was +1.1, the audio was +1.1 and the dropout was 4.
※ 자성도료의 조성※ Composition of magnetic paint
강자성 분말 : 100 중량부Ferromagnetic powder: 100 parts by weight
카아본 블랙 : 1 중량부Carbon black: 1 part by weight
알루미나 : 6 중량부Alumina: 6 parts by weight
폴리우레탄 : 12 중량부Polyurethane: 12 parts by weight
폴리염화비닐 : 12 중량부Polyvinyl chloride: 12 parts by weight
윤활제 : 1 중량부Lubricant: 1 part by weight
지방산 : 1 중량부Fatty acid: 1 part by weight
지방산 에스테르 : 1 중량부Fatty acid ester: 1 part by weight
경화제 : 4중량부Curing agent: 4 parts by weight
유기 용매 : 사이클로헥사논140 중량부Organic solvent: 140 parts by weight of cyclohexanone
메틸에틸케톤140 중량부Methyl ethyl ketone 140 parts by weight
톨루엔 120 중량부Toluene 120 parts by weight
[실시예 2 내지 4 및 비교예 1 내지 4][Examples 2 to 4 and Comparative Examples 1 to 4]
하기 표 1에 나타낸 바와 같은 강자성 분말을 사용한 것을 제외하고는 실시예 1과 동일한 절차를 반복하였다. 각 예의 전자변환특성 및 드롭아웃은 하기 표 2에 제시된다.The same procedure as in Example 1 was repeated except that ferromagnetic powder as shown in Table 1 was used. The electron conversion properties and dropouts of each example are shown in Table 2 below.
상기한 표 2의 결과로부터 알 수 있는 바와 같이 본 발명에 따르는 강자성 분말을 사용한 자기기록매체는 기존의 강자성 분말로 제조된 자기기록 매체 보다 전자 변환 특성에서 오디오(음성)신호가 20㎐∼20㎑전폭에 걸쳐 우수하게 나타나며, 또한 RF출력은 기존과 유의차가 없으며 비디오 테이프의 품질을 좌우하는 드롭아우트는 향상된다.As can be seen from the results of Table 2, the magnetic recording medium using the ferromagnetic powder according to the present invention has an audio (voice) signal of 20 Hz to 20 Hz in electronic conversion characteristics than a magnetic recording medium made of conventional ferromagnetic powder. It is excellent across the board, and the RF output is insignificant, and the dropout that determines the quality of the video tape is improved.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020010077000A KR20030046755A (en) | 2001-12-06 | 2001-12-06 | Magnetic recording medium |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020010077000A KR20030046755A (en) | 2001-12-06 | 2001-12-06 | Magnetic recording medium |
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| Publication Number | Publication Date |
|---|---|
| KR20030046755A true KR20030046755A (en) | 2003-06-18 |
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| KR1020010077000A KR20030046755A (en) | 2001-12-06 | 2001-12-06 | Magnetic recording medium |
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| KR (1) | KR20030046755A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2019175538A (en) * | 2018-03-29 | 2019-10-10 | 富士フイルム株式会社 | Magnetic tape and magnetic recording and reproducing device |
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2001
- 2001-12-06 KR KR1020010077000A patent/KR20030046755A/en not_active Application Discontinuation
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2019175538A (en) * | 2018-03-29 | 2019-10-10 | 富士フイルム株式会社 | Magnetic tape and magnetic recording and reproducing device |
| JP2021044054A (en) * | 2018-03-29 | 2021-03-18 | 富士フイルム株式会社 | Magnetic tape and magnetic recording and reproducing device |
| JP2021101406A (en) * | 2018-03-29 | 2021-07-08 | 富士フイルム株式会社 | Magnetic tape and magnetic recording and reproducing device |
| JP7236493B2 (en) | 2018-03-29 | 2023-03-09 | 富士フイルム株式会社 | Magnetic tapes and magnetic recording/playback devices |
| JP7422912B2 (en) | 2018-03-29 | 2024-01-26 | 富士フイルム株式会社 | Magnetic tape and magnetic recording/playback equipment |
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