JPS6021236B2 - Manufacturing method of high recording density magnetic disk - Google Patents
Manufacturing method of high recording density magnetic diskInfo
- Publication number
- JPS6021236B2 JPS6021236B2 JP926978A JP926978A JPS6021236B2 JP S6021236 B2 JPS6021236 B2 JP S6021236B2 JP 926978 A JP926978 A JP 926978A JP 926978 A JP926978 A JP 926978A JP S6021236 B2 JPS6021236 B2 JP S6021236B2
- Authority
- JP
- Japan
- Prior art keywords
- film
- plating
- magnetic
- forming
- copper
- 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.)
- Expired
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- Paints Or Removers (AREA)
- Electroplating And Plating Baths Therefor (AREA)
- Electroplating Methods And Accessories (AREA)
- Magnetic Record Carriers (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Description
【発明の詳細な説明】
本発明は高記録密度磁気ディスクを製造するに当って、
磁性めつき膜用の下地として無欠陥の下地めつき膜を形
成するめつき方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION In manufacturing a high recording density magnetic disk, the present invention
The present invention relates to a plating method for forming a defect-free base plating film as a base for a magnetic plating film.
電子計算機の外部記憶装置に用いる磁気ディスクとして
は、一般にアルミニウム合金素材上に記録媒体としてy
−Fe203等の磁性鉄酸化物を塗布した塗布型ディス
クが用いられている。Magnetic disks used in external storage devices for computers are generally made of aluminum alloy material as a recording medium.
-A coated disk coated with magnetic iron oxide such as Fe203 is used.
しかし、この型のディスクでは、記録媒体の膜厚を磁性
特性やその均一性を損なわずに薄くすることに限界があ
るため(最低約0.5山m)、磁気ディスクの記録密度
も10000bits/inchが限度で、これ以上高
くすることは困難とされている。これに対してNi−C
o一P等の磁性めつき膜を用いた場合には磁気特性が優
れて均一なより薄い(0.05〜0.1仏m)薄膜の記
録媒体の形成が可能である。このため、記録媒体として
磁性めつき膜を用いた場合には、記録密度20000〜
2500帆船/inchの極めて高記録密度の磁気ディ
スクが原理的に可能となる。しかし、記録媒体として滋
性めつき膜を用いた磁気ディスク(以下めつきディスク
という)では、塗布型ディスクに対して熱安性性が優れ
、より平坦かつ平滑で無欠陥性の優れた下地面が必要で
ある。塗布後の磁気ディスクでは、研摩されたアルミニ
ウム合金基体表面を下地としてこの上にそのまま記録媒
体を塗布しているが、めつきディスク用の下地面として
は適さない。何故ならば、アルミニウム合金基体表面に
は直接磁性めつきすることができないためである。この
ため、アルミニウム合金基体表面に予め電気めつき可能
な処理皮膜を形成し、この上に比較的硬質の非磁性下地
めつき膜を形成した後、この下地めつき膜を研摩して、
必要特性を満足する下地面を作成する必要がある。この
下地めつき膜としては、従来イb学ニッケル−リンめつ
き腰や電気ニッケル一リンめつき膜が用いられているが
、このめつき膜は熱安定性に問題があり、めつきディス
クの高記録密度化の大きな障害となっていた。何故なら
ば、高誼緑密度のめつきディスクは、媒体の磁気特性の
安定化や磁性めつき膜表面に薄膜の酸化物保護膜を形成
するために、300℃以上の熱処理を必要とするが、上
記のニッケル−リンめつき膜は熱処理で強磁性体に変化
するためである。そこで発明者はこれに代る熱安定性に
優れた非磁性の下地めつき膜として、電気鋼−すず合金
めつき腰が適していることを見い出した(特公昭51−
109978)。しかし、従来の銅−すずめつき浴で下
地めつき膜を形成した場合には、めつき面に直径10山
m◇〜150山mJのへこみ(以下ビットという)の発
生を防止することができなかった。このため機械研摩後
の研摩面にも5rm0以上の欠陥が多数存在し、これが
磁性めつき膜に影響を与えるため、記録特性の面で信号
が記録されないとう、いわゆるビット落ちの問題があっ
た。すなわち、このような下地面の欠陥が、高記録密暖
めつきディスク製造の重大な障害となっていた。本発明
の目的は、上託した従来技術の欠点をなくし、高記録密
度のめつきディスクを製造するための、無欠陥下地めつ
き膜の形成法を提供するにある。However, with this type of disk, there is a limit to how thin the film thickness of the recording medium can be made without impairing the magnetic properties or its uniformity (at least about 0.5 m), so the recording density of the magnetic disk is also 10,000 bits/m. The limit is 1 inch, and it is difficult to increase it any higher. On the other hand, Ni-C
When a magnetic plating film such as O1P is used, it is possible to form a thinner recording medium (0.05 to 0.1 French m) with excellent magnetic properties and uniformity. Therefore, when a magnetic plated film is used as a recording medium, the recording density is 20,000~
In principle, a magnetic disk with an extremely high recording density of 2,500 sailboats/inch is possible. However, magnetic disks that use a nutritious plated film as a recording medium (hereinafter referred to as plated disks) have better thermal stability than coated disks, and have a flatter, smoother, and defect-free base surface. is necessary. In the magnetic disk after coating, the polished aluminum alloy substrate surface is used as a base and a recording medium is coated thereon as it is, but this is not suitable as a base for a plated disk. This is because magnetic plating cannot be directly applied to the surface of an aluminum alloy substrate. For this purpose, a treated film that can be electroplated is formed on the surface of the aluminum alloy substrate in advance, a relatively hard non-magnetic base plating film is formed thereon, and then this base plating film is polished.
It is necessary to create a base surface that satisfies the required characteristics. Conventionally, industrial nickel-phosphorus plating and electrolytic nickel-phosphorus plating have been used as the base plating film, but these plating films have problems with thermal stability and cannot be used for plating discs. This was a major obstacle to achieving higher recording densities. This is because plated disks with high green density require heat treatment at 300°C or higher in order to stabilize the magnetic properties of the medium and to form a thin oxide protective film on the surface of the magnetic plated film. This is because the above-mentioned nickel-phosphorous plated film changes into a ferromagnetic material by heat treatment. Therefore, the inventor discovered that an electrical steel-tin alloy plating film was suitable as an alternative non-magnetic base plating film with excellent thermal stability.
109978). However, when a base plating film is formed in a conventional copper-tin plating bath, it is not possible to prevent the formation of dents (hereinafter referred to as bits) with a diameter of 10 m◇ to 150 mJ on the plating surface. Ta. For this reason, there are many defects of 5rm0 or more on the polished surface after mechanical polishing, and since these affect the magnetic plating film, there is a so-called bit drop problem in which signals are not recorded in terms of recording characteristics. In other words, such defects on the underlying surface have been a serious hindrance to the production of high-density, warm-up disks. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for forming a defect-free underplating film for producing a plated disk with high recording density, eliminating the drawbacks of the prior art.
さらに、具体的には銅一すずめつき膜表面のビット発生
防止に効果的な銅−すずめつき格で銅−すずめつき膜の
形成法を提供するにある。上記目的を達成するため発明
者は、電気鋼−すずめつき俗として、シアン化第一銅2
0〜50夕/〆、すず酸カリウム(3水塩)30〜55
タノ〆、シアン化カリウム40〜100夕/夕、水酸化
カリウム10〜30夕/その組成から成るめつき裕また
は上諦めつき格に一般式R○(CQC日20)nH(た
だしRはCmH2ね+p,mは12〜18の整数、nは
20〜50の整数、pは1または−1)で表わされる界
面活性剤を添加しためつき格がビット発生に極めて効果
的であることを見し、出した。そして、上記めつき格で
形成した銅一すず下地めつき膜を機械研摩して得られた
めつきディスクの下地面には、5rm◇以上の欠陥がほ
とんど認められず、5仏mJ以上の欠陥のないめつきデ
ィスクを歩蟹りよく製造できることがわかった。以下実
施例により本発明を詳述する。Furthermore, specifically, it is an object of the present invention to provide a method for forming a copper-tin-plated film with a copper-tin-plated layer that is effective in preventing the occurrence of bits on the surface of the copper-tin-plated film. In order to achieve the above object, the inventor has developed a method for producing electrical steel with cuprous cyanide 2.
0-50 evening/final, potassium stannate (trihydrate) 30-55
Tano〆, Potassium cyanide 40-100 evenings/night, Potassium hydroxide 10-30 evenings/The general formula R○ (CQC day 20) nH (where R is CmH2+p, We found that adding a surfactant (m is an integer of 12 to 18, n is an integer of 20 to 50, and p is 1 or -1) is extremely effective for bit generation, and did. On the base surface of the plating disk obtained by mechanically polishing the copper-tin base plating film formed with the above plating grade, almost no defects of 5rm◇ or more were observed, and no defects of 5 mJ or more were observed. It has been found that it is possible to easily produce discs with no plating. The present invention will be explained in detail with reference to Examples below.
実施例 1 第1図はめつきディスクの層構成を示した図である。Example 1 FIG. 1 is a diagram showing the layer structure of a plated disk.
第1図において、磁気ディスク基体1は耐食アルミニウ
ム合金素材を機械加工して製作した平坦な表面を有する
外径356側、内径168柵、厚さ2脚の円板である。
このディスク基体の両面に亜鉛置換処理とシアン化鋼め
つきにより、厚さ2ムm〜5rmの処理皮膜2を形成さ
せた。次に、この処理膜2の上に表に示す浴組成とめつ
き条件により、厚さ30rm、皮膜の銅含有率90%の
銅−すず合金下地めつき膜3を形成した。In FIG. 1, a magnetic disk base 1 is a disk having a flat surface, an outer diameter of 356 mm, an inner diameter of 168 mm, and a thickness of 2 legs, manufactured by machining a corrosion-resistant aluminum alloy material.
A treated film 2 having a thickness of 2 mm to 5 rm was formed on both surfaces of this disk substrate by zinc substitution treatment and cyanide steel plating. Next, a copper-tin alloy base plating film 3 having a thickness of 30 rm and a copper content of 90% was formed on the treated film 2 according to the bath composition and plating conditions shown in the table.
表中、A格は従来から下地めつき格として用いていたも
のであり、B浴は本発明の浴、さらにC格はビット発生
防止剤としてポリオキシェチレンアルコールェーテル系
の界面活性剤をB格に添加した格である。なお、銅−す
ず下地めつきは、侍公昭45‐9447に記載されてい
る穴あきジャマ板と補助陰極とを用いることを特徴とす
る均一なめつき厚さ表を得るための篭気めつき糟中で、
ディスク基体を回転させながら行った。In the table, the A rating is the one conventionally used as a base plating rating, the B bath is the bath of the present invention, and the C rating is a polyoxyethylene alcohol ether-based surfactant as a bit generation prevention agent. is added to the B rating. Note that the copper-tin undercoat plating is performed using a plating method to obtain a uniform plating thickness table, which is characterized by using a perforated jammer plate and an auxiliary cathode as described in Samurai Koko Sho 45-9447. Inside,
This was done while rotating the disk base.
3種類のめつき格で鰭気めつきして得られた鋼一すず合
金下地めつき膜表面のディスク片面(面積7.7dm2
)当りのビット(大きさ10一m◇以上)数は、従釆の
A浴では平均約50の固であったが、本発明のB浴では
平均10個に、またC格では平均3個と著しく減少した
。One side of the disc (area 7.7 dm
) The number of bits (size 101 m◇ or more) was about 50 on average in the secondary A bath, but on average 10 in the B bath of the present invention, and 3 on average in the C grade. decreased significantly.
次に、これら3種類のめつき俗で得られた銅−すず合金
下地めつき膜を機械的に研摩して得られた下地面の5r
m0以上の欠陥数と研摩量との関係は第2図のようにな
った。なお、第2図はそれぞれのめつき俗で得られたデ
ィスクの代表例を示してある。従釆のA格でめつきして
得られたディスクの下地めつき膜は第2図6に示す如く
研摩後も欠陥数が多く、欠陥のない下地面を得るために
は20山m以上研摩する必要があり、欠陥のない下地面
を有するめつきディスク製造の歩留りは5%以下であっ
た。これに対して本発明のB俗でめつきして得られたデ
ィスクの下地めつき膜は第2図7に示す如く欠陥が極め
て少なく、8リmの研摩をすることによって、欠陥のな
い下地面を有するディスク製造の歩留りを約70%に向
上できることがわかつた。また、本発明のC格でめつき
して得られたディスクの下地めつき膜は第2図8に示す
如くさらに欠陥が少なく、6〃mの研摩をすることによ
って欠陥のない下地面を有するディスク製造の歩留りを
約80%に向上できることがわかった。Next, the copper-tin alloy base plating film obtained by these three types of plating methods was mechanically polished to obtain a 5R
The relationship between the number of defects larger than m0 and the amount of polishing is shown in FIG. Incidentally, FIG. 2 shows representative examples of disks obtained with each plating method. The base plated film of the disk obtained by plating with the A rating of the secondary has a large number of defects even after polishing, as shown in Figure 2 6, and in order to obtain a defect-free base surface, it is necessary to polish more than 20 peaks. The yield for producing plated disks with defect-free substrates was less than 5%. On the other hand, the base plated film of the disk obtained by plating with the B method of the present invention has extremely few defects as shown in FIG. It has been found that the yield of manufacturing disks with a ground surface can be improved to about 70%. In addition, the base plating film of the disc obtained by plating with the C rating of the present invention has even fewer defects as shown in FIG. It has been found that the yield of disk manufacturing can be improved to about 80%.
このように、本発明の電気銅一すずめつき格を用いてめ
つきディスクの下地めつき際を形成することによつて、
従釆よりもはるかに少ない研摩量で欠陥のない下地面を
得ることができることがわかった。このため銅一すず合
金下地めつき膜3上に所定の磁性めつき膜4を形成し、
さらにこの上に保護膜5を形成することにより、ビット
落ちのない高記録密度の磁気ディスクの製造が可能にな
った。実施例 2第1表に示したB俗の代りに、シアン
化第一銅20〜50夕/そ、すず酸カリウム(3水塩)
30〜55夕/夕、シアン化カリウム40〜100夕/
夕、水酸化カリウム10〜30夕/その組成からなる各
種電気鋼一すずめつき浴でめつきして得られた各種鋼−
すず合金下地めつき膜3の組成は、銅80〜95%とな
るが、銅一すず合金下地めつき膜の性質はB俗で得られ
たものとほとんど変らず、欠陥数もB浴と同程度に少な
く、高記録密度のめつきディスクの製造に利用できるこ
とがわかった。As described above, by forming the base plating edge of a plated disk using the electrolytic copper-tin plating plate of the present invention,
It has been found that a defect-free surface can be obtained with a much smaller amount of polishing than with the secondary method. For this purpose, a predetermined magnetic plating film 4 is formed on the copper-tin alloy base plating film 3,
Furthermore, by forming the protective film 5 thereon, it has become possible to manufacture a magnetic disk with high recording density and no bit loss. Example 2 In place of B general shown in Table 1, cuprous cyanide 20 to 50 minutes/so, potassium stannate (trihydrate)
30-55 evenings/evening, potassium cyanide 40-100 evenings/
Potassium hydroxide for 10 to 30 min/Various electrical steels having the same composition -Various steels obtained by plating in a tin plating bath-
The composition of the tin alloy base plating film 3 is 80 to 95% copper, but the properties of the copper-tin alloy base plating film are almost the same as those obtained in B bath, and the number of defects is also the same as in B bath. It was found that it can be used to manufacture plated disks with a high recording density.
また、上記の各種電気鋼−すずめつき裕中に、一般式R
0(CQCH20)nH(ただしRはCmH2h十p,
mは12〜18の整数、nは20〜50の整数、pは1
または−1)で表わすポリオキシェチレンアルコールェ
ーテル系の界面活性剤を0.05夕/そ〜5夕/その範
囲で添加しためつき浴でめつきして得られた鋼−すず合
金下地めつき面のビット数は、上記界面活性剤を添加し
ない格で得らたものに比較して少なく、高記録密度のめ
つきディスクをより高い歩蟹りで製造することがわかっ
た。なお、本発明の銅−すずめつき俗でめつきして得ら
れた鋼一すず合金下地めつき腰面の欠陥が従来のものに
比較してはるかに少ない理由は、めつきの陰極電流効率
が従来の90%以下に対して、99%以上と非常に高い
ため、陰極面に付着して析出を妨害し、ビット発生の原
因となる水素気泡がほとんど発生しないためと考えられ
る。In addition, the general formula R
0(CQCH20)nH (where R is CmH2h10p,
m is an integer from 12 to 18, n is an integer from 20 to 50, p is 1
Or a steel-tin alloy obtained by plating in a matting bath to which a polyoxyethylene alcohol ether surfactant represented by -1) is added in a range of 0.05 m/s to 5 m/m. It was found that the number of bits on the underplated surface was smaller than that obtained without the addition of the surfactant, and that a plated disk with a high recording density could be produced at a higher rate. The reason why the defects of the steel-tin alloy base-plated waist surface obtained by plating with the copper-tin plating method of the present invention is much less than that of the conventional one is that the cathode current efficiency of plating is lower than that of the conventional one. This is considered to be because hydrogen bubbles, which adhere to the cathode surface and interfere with precipitation and cause bit generation, are hardly generated because the hydrogen content is extremely high at 99% or more, compared to 90% or less.
以上述べたように、従来の電気鋼−すずめつき浴に対し
て、本発明の電気鋼一すずめつき格を用いて、めつきデ
ィスクの下地めつき膜を形成することにより、研摩量を
従来の20ムm以上に対して8仏m以下と著しく少なく
し、研摩コストを減少させるとともに、5一m◇以上の
欠陥のない下地面を有するめつきディスクの製造歩留り
を従来の5%以下から70%以上に向上させることがで
きる。このため、従来できなかった高記録密度のめつき
ディスクの製造が可能になった。As described above, the amount of polishing can be reduced compared to the conventional electric steel-tin plating bath by forming the base plating film on the plating disk using the electric steel-tin plating bath of the present invention. The polishing cost has been significantly reduced from 20 mm or more to 8 French m or less, and the manufacturing yield of plated discs with a defect-free base surface of 51 mm or more has been increased from the conventional 5% or less to 70 mm. % or more. This has made it possible to manufacture plated disks with high recording density, which was previously impossible.
第1図は記録媒体として滋性めつき膜を用いためつきデ
ィスクの層構成を示す断面図、第2図は本発明のめつき
浴の欠陥減少に対する効果を示す図である。
1…・・・磁気ディスク基体、2・・…・処理皮膜、3
・・…・銅−すず合金下地めつき膜、4・・…・滋性め
つき膜、5・・・保護膜、6・・・・・・従来格でめつ
きして得られた鋼一すず下地めつき膜の研摩後の下地面
の欠陥数と研摩量との関係を表わす線、7,8…・・・
本発明の格でめつきして得られた鋼一すず下地めつき膜
の研摩後の下地面の欠陥数と研摩量との関係を表わす線
。
オ丁図
汁Z図FIG. 1 is a sectional view showing the layer structure of a plating disk using a nutritious plating film as a recording medium, and FIG. 2 is a diagram showing the effect of the plating bath of the present invention on reducing defects. 1... Magnetic disk substrate, 2... Treated film, 3
......Copper-tin alloy base plating film, 4...Nutritious plating film, 5...Protective film, 6...Steel obtained by plating with conventional grade. Lines 7 and 8 represent the relationship between the number of defects on the base surface after polishing the tin base plating film and the amount of polishing.
A line showing the relationship between the number of defects on the base surface after polishing of the steel-tin base plating film obtained by plating with the grade of the present invention and the amount of polishing. Ochozu soup Z diagram
Claims (1)
を形成させた後、この表面にシアン化第一銅20〜50
g/l、すず酸カリウム(3水塩)30〜55g/l、
シアン化カリウム40〜100g/l、水酸化カリウム
10〜30g/lの組成から成る電気銅−すず合金めつ
き浴を用いて、銅−すず合金めつき膜を電気めつきによ
つて形成させ、この銅−すず合金めつき膜を研摩して平
坦、かつ平滑な面とし、この面上に磁性膜をめつきによ
つて形成させ、この磁性膜上に保護膜を形成させること
を特徴とする高記録密度磁気デイスクの製造方法。 2 磁気デイスク基体の表面に電気めつきが可能な皮膜
を形成させた後、この表面にシアン化第一銅20〜50
g/l、すず酸カリウム(3水塩)30〜50g/l、
シアン化カリウム40〜100g/l、水酸化カリウム
10〜30g/l、一般式RO(CH_2CH_2O)
nH(ただしRはCmH2m+pであり、nは12〜1
8の整数、nは20〜50の整数、pは1または−1)
で表わされる界面活性剤を添加した電気銅−すず合金め
つき浴を用いて、銅−すず合金めつき膜を電気めつきに
よつて形成させ、この銅−すず合金めつき膜を研摩して
平坦、かつ平滑な面とし、この面上に磁性膜をめつきに
よつて形成させ、この磁性膜上に保護膜を形成させるこ
とを特徴とする高記録密度磁気デイスクの製造方法。[Claims] 1. After forming a film capable of electroplating on the surface of a magnetic disk substrate, this surface is coated with 20 to 50% cuprous cyanide.
g/l, potassium stannate (trihydrate) 30-55 g/l,
A copper-tin alloy plating film is formed by electroplating using an electrolytic copper-tin alloy plating bath having a composition of 40 to 100 g/l of potassium cyanide and 10 to 30 g/l of potassium hydroxide. - High recording performance characterized by polishing the tin alloy plated film to make a flat and smooth surface, forming a magnetic film on this surface by plating, and forming a protective film on this magnetic film. Method for manufacturing density magnetic disks. 2 After forming a film that can be electroplated on the surface of the magnetic disk substrate, apply 20 to 50% cuprous cyanide to this surface.
g/l, potassium stannate (trihydrate) 30-50 g/l,
Potassium cyanide 40-100g/l, potassium hydroxide 10-30g/l, general formula RO(CH_2CH_2O)
nH (where R is CmH2m+p, n is 12-1
8 integer, n is an integer from 20 to 50, p is 1 or -1)
A copper-tin alloy plating film is formed by electroplating using an electrolytic copper-tin alloy plating bath to which a surfactant represented by is added, and this copper-tin alloy plating film is polished. 1. A method of manufacturing a high recording density magnetic disk, which comprises forming a flat and smooth surface, forming a magnetic film on this surface by plating, and forming a protective film on the magnetic film.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP926978A JPS6021236B2 (en) | 1978-02-01 | 1978-02-01 | Manufacturing method of high recording density magnetic disk |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP926978A JPS6021236B2 (en) | 1978-02-01 | 1978-02-01 | Manufacturing method of high recording density magnetic disk |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS54103751A JPS54103751A (en) | 1979-08-15 |
JPS6021236B2 true JPS6021236B2 (en) | 1985-05-25 |
Family
ID=11715722
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP926978A Expired JPS6021236B2 (en) | 1978-02-01 | 1978-02-01 | Manufacturing method of high recording density magnetic disk |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6021236B2 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61234819A (en) * | 1985-04-11 | 1986-10-20 | 松下電器産業株式会社 | Rice cooker |
JPS63158236U (en) * | 1987-04-03 | 1988-10-17 | ||
JPH0335216Y2 (en) * | 1985-04-11 | 1991-07-25 | ||
JPH0569531B2 (en) * | 1985-04-11 | 1993-10-01 | Matsushita Electric Ind Co Ltd | |
JPH09504080A (en) * | 1993-10-25 | 1997-04-22 | オー ウント カー オーレンスタイン ウント コッペル アクチェン ゲゼルシャフト | Method for attaching a high pressure hose and a high pressure tube cooperating with a flange |
-
1978
- 1978-02-01 JP JP926978A patent/JPS6021236B2/en not_active Expired
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61234819A (en) * | 1985-04-11 | 1986-10-20 | 松下電器産業株式会社 | Rice cooker |
JPH0335216Y2 (en) * | 1985-04-11 | 1991-07-25 | ||
JPH0569531B2 (en) * | 1985-04-11 | 1993-10-01 | Matsushita Electric Ind Co Ltd | |
JPS63158236U (en) * | 1987-04-03 | 1988-10-17 | ||
JPH09504080A (en) * | 1993-10-25 | 1997-04-22 | オー ウント カー オーレンスタイン ウント コッペル アクチェン ゲゼルシャフト | Method for attaching a high pressure hose and a high pressure tube cooperating with a flange |
Also Published As
Publication number | Publication date |
---|---|
JPS54103751A (en) | 1979-08-15 |
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