KR900003764B1 - Magnetic record media - Google Patents

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KR900003764B1
KR900003764B1 KR1019860009881A KR860009881A KR900003764B1 KR 900003764 B1 KR900003764 B1 KR 900003764B1 KR 1019860009881 A KR1019860009881 A KR 1019860009881A KR 860009881 A KR860009881 A KR 860009881A KR 900003764 B1 KR900003764 B1 KR 900003764B1
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weight
parts
alcohol
fatty acid
magnetic
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KR870005350A (en
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구니하루 후지끼
마사미쯔 나까가와
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니뽕 빅터 가부시끼 가이샤
이노우에 도시야
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    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/84Processes or apparatus specially adapted for manufacturing record carriers
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62Record carriers characterised by the selection of the material
    • G11B5/68Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70Record 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
    • G11B5/71Record 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 lubricant

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  • Paints Or Removers (AREA)

Abstract

A magnetic recording medium has a magnetic layer contg. 1-10 wt.% fatty acid ester on the base of 100 wt.% magnetic powder and 2-10 wt.% phosphate triester of C10-18 alcohol on the base of 100 wt.% magnetic powder. The fatty acid ester comprises C12-18 fatty acid and C3-8 alcohol. The medium is useful for magnetic tapes, e.g. audio or video tape or discs.

Description

자기 기록 매체Magnetic recording media

본 발명은 예를들어 비데오용 테이프나 오디오용 테이프의 자기테이프, 또는 플로피디스크나 하드디스크등의 자기디스크라 불리우는 자기 기록 매체에 관한 것이다.The present invention relates to a magnetic recording medium called, for example, a magnetic tape of a video tape or an audio tape, or a magnetic disk such as a floppy disk or a hard disk.

종래로부터, 자기 기록 매체의 내구성향상을 위해, 자성층속에 특수한 인(P)계 화합물을 포함시키는 것이 제안되어 있다.Conventionally, in order to improve the durability of a magnetic recording medium, it is proposed to include a special phosphorus (P) compound in a magnetic layer.

예를들면, 일본국 특허공개 소56-80828호 공보에 있어서는 자성 도포막층에 탄소수 12 내지 24의 포화 및 불포화지방산군으로부터 선택된 적어도 일종의 화합물, 및 다음의 일반식For example, in Japanese Patent Laid-Open No. 56-80828, at least one compound selected from the group of saturated and unsaturated fatty acids having 12 to 24 carbon atoms in the magnetic coating film layer, and the following general formula

Figure kpo00001
Figure kpo00001

(단, Rl,R2,R3는 탄소수 12 내지 26의 지방족 알킬기)으로 표시되는 지방족 알킬 인산 에스테르의 화합물군으로부터 선택된 적어도 일종의 화합물을 포함하는 자기 기록 매체가 제안되어 있고, 또 일본국 특허공개 소58-108033호 공보에 있어서는 자성 도포막층중에 고급 지방산과, 고급 지방족 알콜의 인산 에스테르를 포함하는 자기 기록 매체가 제안되어 있으며, 또 일본국 특허공개 소58-141440호 공보에 있어서는 자성도포막층중에 지방산 에스테르와, 지방산과, 트리크레실 포스페이트등의 인(P)계 극압제를 포함하는 자기기록 매체가 제안되어 있다.A magnetic recording medium comprising at least one compound selected from the group of aliphatic alkyl phosphate esters represented by R 1 , R 2 , and R 3 is an aliphatic alkyl group having 12 to 26 carbon atoms is proposed, and furthermore, Japanese Patent In Japanese Patent Application Laid-Open No. 58-108033, a magnetic recording medium containing a higher fatty acid and a higher aliphatic alcohol phosphate ester in a magnetic coating film layer is proposed, and in Japanese Patent Application Laid-open No. 58-141440, a magnetic coating film is proposed. A magnetic recording medium containing a fatty acid ester, a fatty acid, and a phosphorus (P) -based extreme pressure agent such as tricresyl phosphate in a layer has been proposed.

이들 제안에 따른 자기 기록 매체는 확실하게 마찰계수가 줄어들어 주행성이 개선되고, 스틸 재생특성도 향상하며, 내구성이 좋아지지만, 이것으로 충분하지만은 않다. 특히, 고온(약 40 내지 60℃) 혹은 고온다습(예를들면,60℃에서 80%RH)한 나쁜 환경하에 있어서는 내구성이 충분치 않은 결점이 있다.The magnetic recording media according to these proposals reliably reduce the coefficient of friction, thereby improving running characteristics, improving steel reproduction characteristics, and improving durability, but this is not sufficient. In particular, there is a drawback in that the durability is not sufficient in a bad environment such as high temperature (about 40 to 60 ° C) or high temperature and high humidity (for example, 80% RH at 60 ° C).

본 발명자는 상기의 문제점에 대한 연구를 행한결과, 자성분 100중량부에 대해 탄소수 12 내지 18의 포화 또는 불포화지방산과 탄소수 3 내지 8의 알콜로 이루어지는 지방산 에스테르 약 1 내지 10중량부와, 자성분 100중량부에 대해 탄소수 10 내지 18의 알콜의 삼치환 인산 에스테르 약 2 내지 10중량부를 자성층중에 함유 또는 자성층 표면에 마련한 자기 기록 매체는 내구성이 한층 향상되며, 특히 고온 혹은 고온다습한 나쁜 환경하에 있어서도 내구성이 좋다는 것을 알아내었다.The present inventors have conducted research on the above-mentioned problems. As a result, about 1 to 10 parts by weight of a fatty acid ester composed of saturated or unsaturated fatty acids having 12 to 18 carbon atoms and alcohol having 3 to 8 carbon atoms, The magnetic recording medium containing about 2 to 10 parts by weight of trisubstituted phosphate esters of alcohols having 10 to 18 carbon atoms in 100 parts by weight in the magnetic layer or provided on the surface of the magnetic layer is further improved in durability, especially in a high temperature or high temperature and high humidity environment. I found it durable.

또한, 탄소수 12 내지 18의 포화 또는 불포화지방산으로서는 예를들어 라우르산, 미리스트산, 팔미트산, 스테아르산, 올레산등이 있으며, 또 탄소수 3 내지 8의 알콜로서는 프로필알콜, 부틸알콜, 아밀알콜, 이소부틸알콜, 이소아밀알콜, 이소헥실알콜, 이소옥틸알콜등이 있고, 그중에서도 이소부틸알콜등과 같은 (CH3)CH-(CH2)n-OH 형태의 측쇄를 갖는 1가 알콜의 것이 특히 바람직하다.Saturated or unsaturated fatty acids having 12 to 18 carbon atoms include, for example, lauric acid, myristic acid, palmitic acid, stearic acid, and oleic acid, and alcohols having 3 to 8 carbon atoms include propyl alcohol, butyl alcohol, and amyl. Alcohols, isobutyl alcohol, isoamyl alcohol, isohexyl alcohol, isooctyl alcohol, and the like. Among them, monohydric alcohols having side chains in the form of (CH 3 ) CH- (CH 2 ) n -OH such as isobutyl alcohol Is particularly preferred.

즉, 탄소수 10 내지 18의 알콜의 삼치환 인산 에스테르와 지방산에스테르를 함께 사용하는 경우에 있어서는 이 지방산에스테르의 알콜성분은 이소부틸알콜등과 같은 측쇄를 갖는 형태의 것인 쪽이 더 한층 효과적인 것이다.That is, when trisubstituted phosphate esters of fatty acids having 10 to 18 carbon atoms and fatty acid esters are used together, the alcohol component of the fatty acid ester is more effective in the form of having a side chain such as isobutyl alcohol or the like.

또, 탄소수 10 내지 18의 알콜로서는 예를들어 도데실알콜, 트리데실알콜, 미리스틸알콜, 펜타데실알콜, 세틸알콜, 헵타데실알콜, 옥타데실알콜등의 직쇄를 갖는 지방족 포화알콜이나 또는 측쇄를 갖는 형태의 지방족 포화알콜, 혹은 불포화형태의 것이있다.As the alcohol having 10 to 18 carbon atoms, for example, an aliphatic saturated alcohol having a straight chain such as dodecyl alcohol, tridecyl alcohol, myristyl alcohol, pentadecyl alcohol, cetyl alcohol, heptadecyl alcohol, octadecyl alcohol, or a side chain may be used. Aliphatic saturated alcohols in the form of, or unsaturated ones.

또한, 이들 지방산에스테르 및 삼치환 인산 에스테르의 양은 너무 적으면 그만큼 효과가 약하고, 역으로 너무 많으면 스며나옴등이 현저히 일어나므로, 자성분 100중량부에 대하여 전자는 약 1 내지 10중량부, 후자는 약 2 내지 10중량부의 비율인 것이 중요하다. 특히, 삼치환 인산 에스테르의 양이 너무 적은 경우에는, 내구성 향상효과는 거의 인정되지 않게된다.In addition, if the amount of these fatty acid esters and trisubstituted phosphate esters is too small, the effect is weak. If the amount is too large, bleeding occurs remarkably, the former is about 1 to 10 parts by weight, and the latter is about 100 parts by weight of the magnetic component. It is important that the ratio is about 2 to 10 parts by weight. In particular, when the amount of the trisubstituted phosphate ester is too small, the effect of improving durability is hardly recognized.

[실시예 1]Example 1

Co함유, γ-Fe2O3100중량부, 염화비닐-아세트산 비닐-비닐 알콜 공중합체(미국 U.C.C. 사제의 VAGH)10중량부, 폴리우레탄 에라스토머(니혼 폴리우레탄 고교 가부시끼 가이샤 제의 N2304) 10중량부, 레시틴 1중량부, 카본 블랙 5중량부, 알루미나 분말 5중량부, 톨루엔과 메틸 에틸 케톤과 메틸 이소부틸 케톤의 등량혼합용제 300중량부를 샌드밀로 약 20시간 혼합 분산하고, 그후 이것에 활제로서 스테아르산 이소아밀 3중량부 및 트리(도데실) 인산 에스테르 3중량부를 첨가하며, 또 경화제로서 폴리이소시아네이트(니혼 폴리우레탄 고교 가부시끼 가이샤 제의 클로네아트L) 5중량부를 가해주고, 이렇게 해서 얻어진 자성도료를 약 75/μm 두께의 폴리에스테르 필름등의 비자성 지지체면상에 양면도포한 후, 이를 캘린더로 표면 평활화처리하고, 그리고 열처리하여 경화반응을 행한뒤, 130mm의 직경으로 타발하여 자기디스크등의 자기 기록매체를 제작한다.Co-containing, 100 parts by weight of γ-Fe 2 O 3, 10 parts by weight of a vinyl chloride-vinyl acetate-vinyl alcohol copolymer (VAGH manufactured by UCC, USA), polyurethane elastomer (N2304, manufactured by Nippon Polyurethane Co., Ltd.) 10 parts by weight, 1 part by weight of lecithin, 5 parts by weight of carbon black, 5 parts by weight of alumina powder, 300 parts by weight of an equal mixture of toluene, methyl ethyl ketone and methyl isobutyl ketone are dispersed and mixed with a sand mill for about 20 hours. 3 parts by weight of isoamyl stearate and 3 parts by weight of tri (dodecyl) phosphate ester are added to the lubricant, and 5 parts by weight of polyisocyanate (Clonaret L manufactured by Nihon Polyurethane Co., Ltd.) is added as a curing agent. The magnetic coating thus obtained was coated on both sides of a nonmagnetic support surface such as a polyester film having a thickness of about 75 / μm, and then surface smoothed with a calender, and cured by heat treatment. After performing the response, emitted by the other diameter of 130mm to produce a magnetic recording medium such as a magnetic disk.

[실시예 2 내지 6][Examples 2 to 6]

실시예1에 있어서의 스테아르산 이소아밀 및 트리(도데실) 인산 에스테르 대신에, 스테아르산 이소아밀 1중량부 및 트리(도데실) 인산 에스테르 5중량부(실시예 2), 스테아르산 부틸 3중량부 및 트리(도데실) 인산 에스테르 3중량부(실시예 3), 스테아르산 부틸 3중량부 및 트리(옥타데실) 인산 에스테르 3중량부(실시예 4), 스테아르산 이소옥틸 3중량부 및 트리(옥타데실) 인산 에스테르 3중량부(실시예 5), 라우르산 이소옥틸 3중량부 및 트리(옥타데실) 인산 에스테르 3중량부(실시예 6)를 사용하여 마찬가지로 자기 기록 매체의 제작을 행한다.Instead of isoamyl stearate and tri (dodecyl) phosphate ester in Example 1, 1 part by weight of isoamyl stearate and 5 parts by weight of tri (dodecyl) phosphate ester (Example 2), 3 parts of butyl stearate 3 parts by weight of part and tri (dodecyl) phosphate ester (example 3), 3 parts by weight of butyl stearate and 3 parts by weight of tri (octadecyl) phosphate ester (example 4), 3 parts by weight of isooctyl stearate and tri A magnetic recording medium was similarly produced using 3 parts by weight of (octadecyl) phosphate ester (Example 5), 3 parts by weight of isooctyl laurate and 3 parts by weight of tri (octadecyl) phosphate ester (Example 6). .

[비교예 1 내지 7][Comparative Examples 1 to 7]

실시예 1에 있어서의 스테아르산 이소아밀 및 트리(도데실) 인산 에스테르 대신에, 올레산 3중량부 및 트리(옥타데실) 인산 에스테르 3중량부(비교예1), 미리스트산 3중량부 및 트리(도데실) 인산 에스테르 3중량부(비교예 2), 스테아르산 부틸 5.7중량부 및 트리(도데실) 인산 에스테르 0.3중량부(비교예 3), 올레산 6중량부(비교예 4), 스테아르산 부틸 6중량부(비교예 5), 트리(도데실) 인산 에스테르 6중량부(비교예 6), 올레산 3중량부 및 스테아르산 부틸 3중량부(비교예 7)를 사용하여 마찬가지로 자기 기록 매체의 제작을 행한다.3 parts by weight of oleic acid and 3 parts by weight of tri (octadecyl) phosphate ester (Comparative Example 1), 3 parts by weight of myristic acid and tree, instead of isoamyl stearate and tri (dodecyl) phosphate ester in Example 1 (Dodecyl) phosphate ester 3 parts by weight (Comparative Example 2), butyl stearate 5.7 parts by weight and tri (dodecyl) phosphate ester 0.3 parts by weight (Comparative Example 3), oleic acid 6 parts by weight (Comparative Example 4), stearic acid 6 parts by weight of butyl (Comparative Example 5), 6 parts by weight of tri (dodecyl) phosphate ester (Comparative Example 6), 3 parts by weight of oleic acid and 3 parts by weight of butyl stearate (Comparative Example 7) We produce.

상기 각 예에서 얻어진 자기 기록 매체에 대해, 구동 토오크 및 통과횟수(내구성)를 조사하면, 표에 나타난 바와같다.The drive torque and the number of passes (durability) of the magnetic recording medium obtained in each of the above examples are as shown in the table.

[표 1]TABLE 1

Figure kpo00002
Figure kpo00002

·구동 토오크는 JISC6291-1983의 회전토오크 측정에 준하여 행해졌다.Driving torque was performed according to the rotational torque measurement of JISC6291-1983.

·통과횟수는 JISC6291-1983의 내구성시험에 준하며, 마쯔시다 덴끼 산교 가부시끼 가이샤제의 JU581의 구동장치를 사용하여 동일트랙의 내구 통과횟수를 측정하였다.The number of passes was determined according to the durability test of JISC6291-1983, and the endurance number of passages of the same track was measured using a driving device of JU581 manufactured by Matsushita Denki Sangyo Co., Ltd ..

이 표에서 알 수있는 바와같이 본 발명의 자기 기록 매체는 구동 토오크가 작아서 마찰계수는 작으며 또한 통과횟수가 많아서 내구성이 뛰어나고, 특히 저온에서 고온 또는 고온다습한 넓은 조건의 환경하에서 내구성이 뛰어난 것임에 대해, 비교예1 및 2에 나타낸 바와같은 지방산과 삼치환 인산 에스테르를 함께 사용한 형태의 자기 기록 매체에서는 구동 토오크가 작지만 내구성은 불충분하며, 또 비교예4에 나타낸 바와같은 삼치환 인산 에스테르를 사용하지 않고 지방족 단독형태로 된 자기 기록 매체에서는 내구성이 현저히 불충분하고, 또 비교예5에 나타낸 바와같은 삼치환 인산 에스테르를 사용하지 않고 지방산 에스테르 단독형태로된 자기 기록 매체에서는 구동 토오크가 커서 마찰계수는 크고 또한 내구성도 볼충분하며, 또 비교예 6에 나타낸 바와같은 삼치환 인산 에스테르 단독형태의 자기 기록 매체에서는 구동 토오크가 비교적 커서 마찰계수는 비교적 작으며 또한 내구성도 현저히 불충분하고, 또 비교예 7에 나타낸 바와같은 지방산과 지방산 에스테르를 함께 사용한 형태의 자기 기록 매체에서는 내구성이 불충분한 것이다.As can be seen from this table, the magnetic recording medium of the present invention has a low driving torque, a low coefficient of friction, and a high number of passes, so that the magnetic recording medium has excellent durability, particularly under a wide range of conditions at low temperature, high temperature, and high temperature and high humidity. In the magnetic recording medium in which a fatty acid and a trisubstituted phosphate ester are used together as shown in Comparative Examples 1 and 2, the driving torque is small, but the durability is insufficient, and a trisubstituted phosphate ester as shown in Comparative Example 4 is used. However, the durability is remarkably insufficient in the magnetic recording medium in the form of aliphatic sole, and in the magnetic recording medium in the form of fatty acid ester alone without the use of the trisubstituted phosphate ester as shown in Comparative Example 5, the driving torque is large and the coefficient of friction is Large and durable enough, and shown in Comparative Example 6 In the magnetic recording medium of the trisubstituted phosphate ester alone type, the driving torque is relatively large, the coefficient of friction is relatively small, and the durability is remarkably insufficient. Also, the magnetic recording type of the fatty acid and the fatty acid ester as shown in Comparative Example 7 is used. Insufficient durability in the medium.

게다가, 비교예 3에 나타난 바와같이, 지방산에스테르와 삼치환 인산 에스테르가 함께 사용되어도, 삼치환 인산 에스테르의 양이 적은 경우에는 구동 토오크가 커서 마찰 계수는 커지며, 또한 통과횟수도 적어서 내구성은 불충분해지고, 양자를 함께 사용함으로 인한 상승효과는 인정되지 않는 것이다.In addition, as shown in Comparative Example 3, even when the fatty acid ester and the trisubstituted phosphate ester are used together, when the amount of the trisubstituted phosphate ester is small, the driving torque is large, the friction coefficient is large, and the number of passes is also low, which leads to insufficient durability. For example, synergies from using both together will not be recognized.

즉, 지방산에스테르와 삼치환 인산 에스테르를 함께 사용한 경우에 있어서, 그 함께 사용함으로 인한 상승효과가 인정되기 시작하는 것은 삼치환 인산 에스테르가 자성분 100중량부에 대하여 약 2중량부 이하일 경우이다.That is, in the case where the fatty acid ester and the trisubstituted phosphate ester are used together, the synergy effect from the use together is recognized when the trisubstituted phosphate ester is about 2 parts by weight or less based on 100 parts by weight of the magnetic component.

상술한 바와같이, 본 발명에 따른 자기 기록 매체는 자성분 100중량부에 대해 탄소수 12 내지 18의 지방산과 탄소수 3 내지 18의 알콜로 이루어지는 지방산에스테르 약 1 내지 10중량부와, 자성분 100중량부에 대해 탄소수 10 내지 18의 알콜의 삼치환 인산 에스테르 약 2 내지 10중량부를 자성층에 함유시킨 것이기 때문에, 구동 토오크가 작아서 마찰계수는 크고, 따라서 주행성이 양호하며, 또한 통과횟수가 많아서 내구성이 풍부한 것이고, 특히 저온에서 고온 또는 고온다습한 넓은 환경조건하에서 내구성이 풍부하며, 그리고 이들 뛰어난 효과는 지방산 에스테르 및 삼치환 인산 에스테르의 양을 자성분 100중량부에 대해 전자는 약 1 내지 10중량부, 후자는 약 2 내지 10중량부로 해주므로서 얻어지는 것이고, 낮은 비용으로 제공할 수 있는등의 특징을 갖는다.As described above, the magnetic recording medium according to the present invention has about 1 to 10 parts by weight of a fatty acid ester composed of 12 to 18 carbon atoms and 3 to 18 carbon atoms and 100 parts by weight of a magnetic component based on 100 parts by weight of a magnetic component. Since about 2 to 10 parts by weight of trisubstituted phosphate esters of alcohols having 10 to 18 carbon atoms are contained in the magnetic layer, the driving torque is small and the friction coefficient is large, thus, the running coefficient is good, and the number of passages is high and the durability is high. In particular, it is rich in durability under a wide range of environmental conditions, particularly at low temperature, high temperature, or high temperature and high humidity, and these outstanding effects are based on the amount of fatty acid ester and trisubstituted phosphate ester with respect to 100 parts by weight of the former, about 1-10 parts by weight, the latter. Is obtained by giving about 2 to 10 parts by weight, and can be provided at a low cost.

Claims (1)

자성층에, 자성분 100중량부에 대해 탄소수 12 내지 18의 지방산과 탄소수 3 내지 8의 알콜로 이루어지는 지방산에스테르 약 1 내지 10중량부와, 자성분 100중량부에 대해 탄소수 10 내지 18의 알콜의 삼치환 인산 에스테르 약 2 내지 10중량부와를 함유시킨 것을 특징으로 하는 자기 기록 매체.About 1 to 10 parts by weight of a fatty acid ester consisting of a fatty acid having 12 to 18 carbon atoms and an alcohol having 3 to 8 carbon atoms relative to 100 parts by weight of the magnetic component, and a alcohol having 10 to 18 carbon atoms relative to 100 parts by weight of the magnetic component. And about 2 to 10 parts by weight of a substituted phosphate ester.
KR1019860009881A 1985-11-29 1986-11-22 Magnetic record media KR900003764B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP60267085A JPS62128022A (en) 1985-11-29 1985-11-29 Magnetic recording medium
JP60-267085 1985-11-29

Publications (2)

Publication Number Publication Date
KR870005350A KR870005350A (en) 1987-06-08
KR900003764B1 true KR900003764B1 (en) 1990-05-31

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KR1019860009881A KR900003764B1 (en) 1985-11-29 1986-11-22 Magnetic record media

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JP (1) JPS62128022A (en)
KR (1) KR900003764B1 (en)
DE (1) DE3640093C2 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2250384C3 (en) * 1972-10-13 1980-12-11 Agfa-Gevaert Ag, 5090 Leverkusen Magnetic storage medium

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JPS62128022A (en) 1987-06-10
DE3640093A1 (en) 1987-06-04
KR870005350A (en) 1987-06-08
DE3640093C2 (en) 1996-04-18
JPH0471249B2 (en) 1992-11-13

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