JPH0356607A - Manufacture of tangsten ultra fine particles - Google Patents

Manufacture of tangsten ultra fine particles

Info

Publication number
JPH0356607A
JPH0356607A JP1189843A JP18984389A JPH0356607A JP H0356607 A JPH0356607 A JP H0356607A JP 1189843 A JP1189843 A JP 1189843A JP 18984389 A JP18984389 A JP 18984389A JP H0356607 A JPH0356607 A JP H0356607A
Authority
JP
Japan
Prior art keywords
particles
fine particles
ultra fine
precipitation
tungsten
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
Application number
JP1189843A
Other languages
Japanese (ja)
Other versions
JP2834199B2 (en
Inventor
Noriaki Nakano
中野 憲明
Sumio Saito
純夫 斉藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JGC Catalysts and Chemicals Ltd
Original Assignee
Catalysts and Chemicals Industries Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Catalysts and Chemicals Industries Co Ltd filed Critical Catalysts and Chemicals Industries Co Ltd
Priority to JP1189843A priority Critical patent/JP2834199B2/en
Publication of JPH0356607A publication Critical patent/JPH0356607A/en
Application granted granted Critical
Publication of JP2834199B2 publication Critical patent/JP2834199B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B82NANOTECHNOLOGY
    • B82YSPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00Nanotechnology for materials or surface science, e.g. nanocomposites
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/05Metallic powder characterised by the size or surface area of the particles
    • B22F1/054Nanosized particles
    • B22F1/056Submicron particles having a size above 100 nm up to 300 nm
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00Making metallic powder or suspensions thereof
    • B22F9/16Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/20Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds

Abstract

PURPOSE:To obtain ultra fine particles of W without passing through mechanical pulverizing process by adjusting pH in water solution of W compound to generate gelling precipitation and executing reduction treatment to the particles obtd. by washing the precipitation under the specific condition at the specific temp. CONSTITUTION:The water solution of W compound of Na2WO4.2H2O, etc., is adjusted to <=pH3 by adding hydrochloric acid, etc., to generate the gelling precipitation. This precipitation is washed until relative electric conductivity in the mother liquor comes to <= 5 X 10<-5>OMEGA<-1>cm<-1> to obtain dispersion liguid with flaky tungstic acid particles dispersed. Water content in the dispersing liquid is vaporized, and after burning the obtd. powder, the reduction treatment is executed at 700 - 1200 deg.C to obtain the black ultra fine particles of W. By this method, the ultra fine particles of W having <=about 0.3mum can be manufac tured.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、タングステン超微粒子の製造方法に関し、さ
らに詳しくは、機械的な粉砕操作なしにタングステン超
微粒子を製造する方法に関する。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing ultrafine tungsten particles, and more particularly to a method for producing ultrafine tungsten particles without mechanical crushing.

〔従来の技術〕[Conventional technology]

タングステン粉末は特殊鋼の成分として、また、タング
ステンカーバイトを主体とする超硬合金の原料として用
いられている。
Tungsten powder is used as a component of special steel and as a raw material for cemented carbide, which is mainly made of tungsten carbide.

そして今日では、IC基板の穴あけ用ドリルの原料など
の用途として、微細なタングステン粉末が求められてい
る。
Nowadays, fine tungsten powder is in demand as a raw material for drills for drilling holes in IC boards.

従来より、タングステン粉末の製造方法としては、酸化
タングステン粉末を水素気流中で700℃以上に加熱し
て還元する方法などが行われている。
Conventionally, tungsten powder has been produced by reducing tungsten oxide powder by heating it to 700° C. or higher in a hydrogen stream.

また、微細なタングステン粉末の製造方浩として特開昭
61−124508号には、バラタングステン酸アンモ
ニウムの結晶を過酸化水素水に溶解せしめ、得られた溶
液を乾燥して固化物を得、ついで該固化物を還元して0
.3〜0.6μmの超微粒子を製造する方法が開示され
ている。
Furthermore, as a method for producing fine tungsten powder, JP-A-61-124508 discloses that ammonium baratungstate crystals are dissolved in hydrogen peroxide solution, the resulting solution is dried to obtain a solidified product, and then The solidified product is reduced to 0
.. A method for producing ultrafine particles of 3 to 0.6 μm is disclosed.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

しかし、上記製造方法においては、得られるタングステ
ン超微粒子の大きさは0.3μm程度が限度で、それ以
下の粒径のタングステン超微粒子の製造は困難であった
However, in the above manufacturing method, the size of the obtained ultrafine tungsten particles is limited to about 0.3 μm, and it is difficult to manufacture ultrafine tungsten particles having a particle size smaller than that.

本発明は、機械的粉砕工程を経ることなしに、従来製造
困難であった0.3μm以下のタングステン超微粒子の
製造方法を提供することを目的とする。
An object of the present invention is to provide a method for producing ultrafine tungsten particles of 0.3 μm or less, which has been difficult to produce in the past, without going through a mechanical crushing process.

〔課題を解決するための手段〕[Means to solve the problem]

本発明のタングステン超微粒子の製造方法は、タングス
テン化合物の水溶液をpH3以下に調整して生成するゲ
ル状沈澱物を、母液の比電導度が5X10−’Ω−’3
−’以下となるまで洗浄し、得られた板状のタングステ
ン酸粒子を温度700〜1200℃で還元することによ
り、上記目的を達成するものである。
The method for producing ultrafine tungsten particles of the present invention involves adjusting an aqueous solution of a tungsten compound to a pH of 3 or less to produce a gel-like precipitate, which has a specific conductivity of 5X10-'Ω-'3.
The above object is achieved by washing until the temperature is below -' and reducing the obtained plate-shaped tungstic acid particles at a temperature of 700 to 1200°C.

以下に本発明に係るタングステン超微粒子の製造方法に
ついて具体的に説明する。
The method for producing ultrafine tungsten particles according to the present invention will be specifically described below.

出発原料となるタングステン化合物としては、タングス
トケイ酸、タングストホウ酸、タングストリン酸、タン
グステン酸塩などが挙げられ、特に、タングステン酸ナ
トリウム、メタタングステン酸ナトリウム、タングステ
ン酸カリウム、タングステン酸カルシウム、タングステ
ン酸マグネシウム、タングステン酸リチウム、メタタン
グステン酸アンモニウム、パラタングステン酸アンモニ
ウムなどのタングステン酸塩は好例であり、本発明では
これらを水溶液として使用する。
Examples of the tungsten compound used as a starting material include tungstosilicic acid, tungstoboric acid, tungstophosphoric acid, and tungstate salts, particularly sodium tungstate, sodium metatungstate, potassium tungstate, calcium tungstate, magnesium tungstate, Tungstate salts such as lithium tungstate, ammonium metatungstate and ammonium paratungstate are good examples and are used in the present invention as an aqueous solution.

このタングステン化合物水溶液の濃度はWO,として0
.5〜7重量%の範囲が望ましい。
The concentration of this tungsten compound aqueous solution is 0 as WO,
.. A range of 5 to 7% by weight is desirable.

該水溶液のpH調整には、塩酸、硝酸、硫酸、などの強
酸が用いられる。
A strong acid such as hydrochloric acid, nitric acid, or sulfuric acid is used to adjust the pH of the aqueous solution.

タングステン化合物水溶液が調整されるpH値は特に重
要で与り、pH3以下好ましくは1〜2の範囲で目的と
するゲル状沈澱物が生成される。
The pH value at which the tungsten compound aqueous solution is adjusted is particularly important, and the desired gel-like precipitate is produced at a pH of 3 or less, preferably in the range of 1 to 2.

pH3より高い場合、後述する洗浄操作で比電導度を5
X10−’Ω一′3−1以下に洗浄しても所望の板状タ
ングステン酸粒子が得られないので適当でない。
If the pH is higher than 3, the specific conductivity can be reduced to 5 by the washing procedure described below.
Even if it is washed to less than X10-'Ω-'3-1, the desired plate-shaped tungstic acid particles cannot be obtained, so this is not suitable.

上記pH調整により生成したゲル状沈澱物を、母液の比
電導度が5X10−sΩ一’ am− ’以下になるま
で脱イオン水を用いて洗浄し、板状のタングステン酸粒
子を得る。母液の比電導度が上記値以上では所望の板状
タングステン酸粒子が得られない。
The gel-like precipitate produced by the above pH adjustment is washed with deionized water until the specific conductivity of the mother liquor becomes 5×10 −sΩ1′ am−′ or less to obtain plate-shaped tungstic acid particles. If the specific conductivity of the mother liquor exceeds the above value, desired plate-shaped tungstic acid particles cannot be obtained.

該板状タングステン酸粒子は、長さ約1〜6μm1幅約
0 .  5 〜3 μm s厚さ約400 〜100
0人の範囲の大きさであることが望ましく、特に、厚さ
が1500人以上では、所望の超微粒子が得られにくい
The plate-shaped tungstic acid particles have a length of about 1 to 6 μm and a width of about 0.5 μm. 5 ~ 3 μm s Thickness approx. 400 ~ 100
It is desirable that the size is in the range of 0.0 mm, and in particular, if the thickness is 1500 mm or more, it will be difficult to obtain the desired ultrafine particles.

上記洗浄操作は、例えば限外濾過法などにより行われる
The above-mentioned washing operation is performed, for example, by ultrafiltration.

得られた板状タングステン酸粒子を温度700〜120
0℃で還元する。この温度範囲であれば、0.01〜0
.  2μmのタングステン超微粒子が得られるが、7
00℃より低い場合は、還元速度が遅く、還元が不完全
であったり、また板状粒子が細かく破壊されないので好
ましくない。一方、1200℃以上での還元は、タング
ステン超微粒子が焼結する傾向にあるので好ましくない
The obtained plate-shaped tungstic acid particles were heated to a temperature of 700 to 120°C.
Reduce at 0°C. In this temperature range, 0.01 to 0
.. Ultrafine tungsten particles of 2 μm are obtained, but 7
If the temperature is lower than 00°C, the reduction rate is slow, the reduction may be incomplete, and the plate-like particles may not be finely broken, which is not preferable. On the other hand, reduction at a temperature of 1200° C. or higher is not preferable because the ultrafine tungsten particles tend to sinter.

還元剤としては、水素、炭素など通常、タングステン粉
末の製造に使用される還元剤が使用可能であり、l〜5
時間の還元時間が適当である。
As the reducing agent, reducing agents normally used in the production of tungsten powder such as hydrogen and carbon can be used.
Time reduction time is appropriate.

なお、還元に先立ち、300〜600℃で1〜5時間加
熱処理をすることが望ましい。この加熱処理により、板
状タングステン酸粒子は板状の形状を保持した状態で酸
化タングステンとなる。
Note that, prior to reduction, it is desirable to perform a heat treatment at 300 to 600°C for 1 to 5 hours. Through this heat treatment, the plate-shaped tungstic acid particles turn into tungsten oxide while maintaining their plate-like shape.

〔実施例〕〔Example〕

試薬特級のタングステン酸ナトリウム(NagW O 
a  ・2H! 0)384gをlllの脱イオン水に
溶解して、濃度約3.  1重量%のタングステン酸ナ
トリウム水溶液を調製した。この水溶液を攪拌しながら
、35重量%塩酸を添加して、DH1.20に調整した
後、4時間静置してレモン色のゲル状沈澱物を得た。得
られた沈澱物の上澄液を除去し、次いで、該沈澱物を脱
イオン水を用いて限外濾過膜(旭化成、マイクローザp
w− i o3)により母液の比電導度が2X10−’
Ω一’ 113 − ’となるまで洗浄して、板状タン
グステン酸粒子が分散した分散液INを得た。該分散液
を電子顕微鏡(TEM)で観察すると、長さ1〜4μm
、幅0.5〜2μm1厚さ600〜700人の板状粒子
が認められた。
Reagent grade sodium tungstate (NagWO
a ・2H! 0) Dissolve 384g in lll of deionized water to give a concentration of approximately 3.0g. A 1% by weight aqueous sodium tungstate solution was prepared. While stirring this aqueous solution, 35% by weight hydrochloric acid was added to adjust the DH to 1.20, and the mixture was allowed to stand for 4 hours to obtain a lemon-colored gel precipitate. The supernatant liquid of the obtained precipitate was removed, and then the precipitate was filtered using an ultrafiltration membrane (Asahi Kasei, Microza P) using deionized water.
w-io3) makes the specific conductivity of the mother liquor 2X10-'
The dispersion liquid IN in which plate-shaped tungstic acid particles were dispersed was obtained by washing until Ω1'113-'. When the dispersion was observed with an electron microscope (TEM), the length was 1 to 4 μm.
, plate-like particles with a width of 0.5 to 2 μm and a thickness of 600 to 700 were observed.

次いで、ロータリーエバボレーターを用いて前記分散液
の水分を蒸発して粉末を得た。この粉末を600℃で2
時間焼成した後、水素雰囲気下に800℃で2時間還元
処理して黒色のタングステン超微粒子を得た。このタン
グステン超微粒子の粒子径を電子顕微鏡法で測定すると
、0.  1〜0.2μmの範囲にあった。
Next, water in the dispersion was evaporated using a rotary evaporator to obtain a powder. This powder was heated at 600℃ for 2
After firing for an hour, reduction treatment was performed at 800° C. for 2 hours in a hydrogen atmosphere to obtain black ultrafine tungsten particles. When the particle diameter of these ultrafine tungsten particles was measured by electron microscopy, it was found to be 0. It was in the range of 1 to 0.2 μm.

〔比較例〕[Comparative example]

試薬特級タングステン酸ナトリウム(NazWO1 ●
2H2 0) 3 8 4 gをIfI!の脱イオン水
に溶解し、この溶液を攪拌しながら、試薬特級の35%
塩酸を添加し、液のpHを5.1とした。
Reagent grade sodium tungstate (NazWO1
2H2 0) 3 8 4 g IfI! of 35% reagent grade, while stirring the solution.
Hydrochloric acid was added to adjust the pH of the solution to 5.1.

4時間静置後、白青色の沈澱が生じたところで、上澄液
を除去し、沈澱を限外濾過膜(旭化成、マイクローザP
W−103)により脱イオン水を用いて母液の比電導度
が2X10−’Ω−’am〜1となるまで洗浄すると共
に液量がllになるまで濃縮した。
After standing for 4 hours, when a white-blue precipitate was formed, the supernatant was removed and the precipitate was filtered through an ultrafiltration membrane (Asahi Kasei, Microza P).
W-103) using deionized water until the specific conductivity of the mother liquor became 2×10-'Ω-'am~1 and concentrated until the liquid volume became 1 liter.

このようにして得られたタングステン酸の沈澱を電子顕
微鏡(TEM)で観察すると実施例で認められた板状粒
子は観測されず、粒径約100人の粒子よりなるゲル状
物であった。このゲル状沈澱をロータリーエバボレータ
ーで水分を蒸発させると容器壁に白青色の固形物が付着
した。
When the tungstic acid precipitate thus obtained was observed using an electron microscope (TEM), the plate-like particles observed in the examples were not observed, and it was found to be a gel-like substance consisting of particles of approximately 100 particles in diameter. When the water content of this gel-like precipitate was evaporated using a rotary evaporator, a whitish-blue solid substance adhered to the wall of the container.

この固形物を取り出し粉砕後、温度600℃で2時間焼
成し酸化タングステンの粉末とし、さらにこの粉末を実
施例と同様に、水素雰囲気下で温度800℃で2時間還
元処理した。得られた黒色のタングステン粉末を電子顕
微鏡(TEM)で観察すると、I〜2μmの粒子である
ことが認められた。
This solid material was taken out, pulverized, and then calcined at a temperature of 600° C. for 2 hours to obtain a tungsten oxide powder, and this powder was further subjected to a reduction treatment at a temperature of 800° C. for 2 hours in a hydrogen atmosphere in the same manner as in the example. When the obtained black tungsten powder was observed with an electron microscope (TEM), it was found to be particles of I to 2 μm.

〔発明の効果〕〔Effect of the invention〕

本発明によれば、機械的粉砕工程を経ることなく、簡便
な方法により従来製造困難であった0.3μm以下のタ
ングステン超微粒子を製造することができる。
According to the present invention, ultrafine tungsten particles of 0.3 μm or less, which have been difficult to produce in the past, can be produced by a simple method without going through a mechanical crushing process.

従って、微細なタングステン粉末が求められる、超硬合
金材料、構造材料、耐熱材料用のタングステン粉末とし
て利用可能である。
Therefore, it can be used as tungsten powder for cemented carbide materials, structural materials, and heat-resistant materials, which require fine tungsten powder.

Claims (1)

【特許請求の範囲】[Claims] タングステン化合物の水溶液をpH3以下に調整して生
成するゲル状沈澱物を、母液の比電導度が5×10^−
^5Ω^−^1cm^−^1以下となるまで洗浄し、得
られた板状のタングステン酸粒子を温度700〜120
0℃で還元することを特徴とするタングステン超微粒子
の製造方法
A gel-like precipitate produced by adjusting an aqueous solution of a tungsten compound to a pH of 3 or lower is prepared when the specific conductivity of the mother liquor is 5 × 10^-
The plate-shaped tungstic acid particles obtained were washed until the resistance became ^5 Ω^-^1 cm^-^1 or less at a temperature of 700 to 120 Ω.
Method for producing ultrafine tungsten particles characterized by reduction at 0°C
JP1189843A 1989-07-21 1989-07-21 Method for producing ultrafine tungsten particles Expired - Lifetime JP2834199B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1189843A JP2834199B2 (en) 1989-07-21 1989-07-21 Method for producing ultrafine tungsten particles

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1189843A JP2834199B2 (en) 1989-07-21 1989-07-21 Method for producing ultrafine tungsten particles

Publications (2)

Publication Number Publication Date
JPH0356607A true JPH0356607A (en) 1991-03-12
JP2834199B2 JP2834199B2 (en) 1998-12-09

Family

ID=16248135

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
JP (1) JP2834199B2 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999049099A1 (en) * 1998-03-25 1999-09-30 Japan Science And Technology Corporation Tungsten super fine particle and method for producing the same
JP2002105632A (en) * 2000-09-29 2002-04-10 Toshiba Corp Tungsten powder and its manufacturing method, and sputtering target and cutting tool
US6852304B2 (en) 2001-07-30 2005-02-08 Mitsubishi Materials Corporation Fine tungsten carbide powder and process for producing the same
JP2007537121A (en) * 2004-05-11 2007-12-20 ハー ツェー シュタルク ゲゼルシャフト ミット ベシュレンクテル ハフツング ウント コンパニー コマンデイトゲゼルシヤフト Tungstic acid and method for producing the same
CN116119719A (en) * 2023-04-18 2023-05-16 崇义章源钨业股份有限公司 Superfine platy tungsten oxide and preparation method thereof

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999049099A1 (en) * 1998-03-25 1999-09-30 Japan Science And Technology Corporation Tungsten super fine particle and method for producing the same
US6440562B1 (en) 1998-03-25 2002-08-27 Kabushiki Kaisha Toshiba Tungsten super fine particle and method for producing the same
JP2002105632A (en) * 2000-09-29 2002-04-10 Toshiba Corp Tungsten powder and its manufacturing method, and sputtering target and cutting tool
US6852304B2 (en) 2001-07-30 2005-02-08 Mitsubishi Materials Corporation Fine tungsten carbide powder and process for producing the same
US7465432B2 (en) 2001-07-30 2008-12-16 Mitsubishi Materials Corp. Fine tungsten carbide powder and process for producing the same
JP2007537121A (en) * 2004-05-11 2007-12-20 ハー ツェー シュタルク ゲゼルシャフト ミット ベシュレンクテル ハフツング ウント コンパニー コマンデイトゲゼルシヤフト Tungstic acid and method for producing the same
CN116119719A (en) * 2023-04-18 2023-05-16 崇义章源钨业股份有限公司 Superfine platy tungsten oxide and preparation method thereof
CN116119719B (en) * 2023-04-18 2023-06-27 崇义章源钨业股份有限公司 Superfine platy tungsten oxide and preparation method thereof

Also Published As

Publication number Publication date
JP2834199B2 (en) 1998-12-09

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