JPH0733551A - Production of heat insulating material for vacuum furnace - Google Patents
Production of heat insulating material for vacuum furnaceInfo
- Publication number
- JPH0733551A JPH0733551A JP5204714A JP20471493A JPH0733551A JP H0733551 A JPH0733551 A JP H0733551A JP 5204714 A JP5204714 A JP 5204714A JP 20471493 A JP20471493 A JP 20471493A JP H0733551 A JPH0733551 A JP H0733551A
- Authority
- JP
- Japan
- Prior art keywords
- heat insulating
- insulating material
- resin
- vacuum furnace
- foam
- 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.)
- Withdrawn
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
- C04B38/0022—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof obtained by a chemical conversion or reaction other than those relating to the setting or hardening of cement-like material or to the formation of a sol or a gel, e.g. by carbonising or pyrolysing preformed cellular materials based on polymers, organo-metallic or organo-silicon precursors
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Dispersion Chemistry (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Thermal Insulation (AREA)
- Emulsifying, Dispersing, Foam-Producing Or Wetting Agents (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は多孔質炭素材料からなる
真空炉用断熱材の製造方法に関する。更に詳しくは、炭
化、又は黒鉛化して断熱材を製造する際に原料として供
する樹脂発泡体の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a vacuum furnace heat insulating material made of a porous carbon material. More specifically, it relates to a method for producing a resin foam used as a raw material when producing a heat insulating material by carbonizing or graphitizing.
【０００２】[0002]
【従来の技術】炭素材料は、耐熱性、耐薬品性等を有す
るため、炉材、電極、断熱材等の分野で利用されてい
る。炭素材料にはピッチコークスを主材料とする原料か
らつくられたもの（特開昭５４−１０３６５４号公報
等）や、ガラス状のもの（特開昭６４−６９５６６号公
報等）や、発泡状のもの（特開昭５４−１０３６５４号
公報等）や、その他にフェルト状のものや黒鉛シート等
があるが、真空炉用断熱材としては、断熱性のみならず
脱気が容易であることが望まれる。本願発明者等は特開
平４−３２５４７４号公報において、樹脂発泡体を２，
０００℃以上で炭化又は黒鉛化して得られる多孔質炭素
材料からなる、軽量かつ断熱性能に優れしかも脱気が容
易な真空炉用断熱材を提供している。しかしながら、こ
の多孔質炭素材料からなる真空炉用断熱材については、
脱気性能のみについてみると、材料に起因するその気孔
構造の差によりフェルト状のもの等に比し必ずしも好ま
しいとは言いがたい点が明らかとなっており、一層の改
善が望まれている。2. Description of the Related Art Since carbon materials have heat resistance, chemical resistance, etc., they are used in the fields of furnace materials, electrodes, heat insulating materials and the like. The carbon material is made of a raw material mainly composed of pitch coke (Japanese Patent Laid-Open No. 54-103654, etc.), glass-like (Japanese Patent Laid-Open No. 64-69566, etc.), and foamed. There are materials such as those disclosed in JP-A-54-103654, felt-like materials, graphite sheets, etc., but it is desirable that the heat insulation material for a vacuum furnace has not only heat insulation but also easy deaeration. Be done. The inventors of the present invention described in JP-A-4-325474 a resin foam of 2,
(EN) Provided is a heat insulating material for a vacuum furnace, which is made of a porous carbon material obtained by carbonization or graphitization at 000 ° C or higher, is excellent in heat insulation performance, and is easily deaerated. However, regarding the vacuum furnace heat insulating material made of this porous carbon material,
Looking only at the degassing performance, it has been clarified that it is not necessarily preferable to the felt-like one due to the difference in the pore structure due to the material, and further improvement is desired.
【０００３】[0003]
【発明が解決しようとする課題】本発明は、脱気性能が
改善された、多孔質炭素材料からなる真空炉用断熱材の
製造方法を提供することを目的とする。SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a vacuum furnace heat insulating material made of a porous carbon material, which has improved degassing performance.
【０００４】[0004]
【課題を解決するための手段】本願発明者等は多孔質炭
素材料からなる真空炉用断熱材を製造するに際し、脱気
性能の一層の改善を図るべく鋭意検討した結果、樹脂発
泡体調製時において整泡剤として一般的に用いられるノ
ニオン系界面活性剤とともにアニオン系界面活性剤を併
せ用いることが有効であることを発見し、本願発明を完
成するに至った。Means for Solving the Problems The inventors of the present invention have made diligent studies in order to further improve degassing performance when manufacturing a heat insulating material for a vacuum furnace made of a porous carbon material. In the above, it was discovered that it is effective to use an anionic surfactant together with a nonionic surfactant generally used as a foam stabilizer, and the present invention has been completed.
【０００５】本発明は、（１）熱硬化性樹脂、発泡剤、
硬化剤及び整泡剤を用いて調製した樹脂発泡体を２，０
００℃以上で炭化又は黒鉛化して真空炉用断熱材を製造
するに際し、樹脂発泡体調製時の整泡剤としてノニオン
系界面活性剤とアニオン系界面活性剤とを併せ用いるこ
とを特徴とする真空炉用断熱材の製造方法、（２）熱硬
化性樹脂として、レゾール型フェノール樹脂を用いる上
記（１）記載の方法、（３）アニオン系界面活性剤とし
て、アルキル置換ベンゼンスルホン酸ナトリウム又は高
級アルコール硫酸エステル塩のうちのいずれかひとつを
用いる上記（１）又は（２）記載の方法、である。The present invention comprises (1) a thermosetting resin, a foaming agent,
A resin foam prepared using a curing agent and a foam stabilizer was added to
A vacuum characterized by using a nonionic surfactant and an anionic surfactant together as a foam stabilizer during the preparation of a resin foam when carbonizing or graphitizing at 00 ° C. or higher to produce a heat insulating material for a vacuum furnace. A method for manufacturing a heat insulating material for a furnace, (2) a method according to the above (1) using a resol type phenol resin as a thermosetting resin, and (3) an alkyl-substituted sodium benzenesulfonate or a higher alcohol as an anionic surfactant. The method according to (1) or (2) above, wherein any one of the sulfate ester salts is used.
【０００６】以下本発明について詳細に説明する。本発
明で使用する真空炉用断熱材は多孔質炭素材料からな
り、これは樹脂を発泡、硬化させて樹脂発泡体とし、こ
の樹脂発泡体を２，０００℃乃至３，０００℃の温度で
不活性ガス雰囲気下或いは真空中で炭化、又は黒鉛化し
て得られるが、これが使用される真空炉の最高使用温度
以上で炭化又は黒鉛化しておくことがより好ましい。こ
のようにして得られた多孔質炭素材料は、真空炉の内壁
に断熱材として取りつけられる。真空炉は、中に被加熱
材料を入れたのち、密閉し、真空ポンプで脱気を行い、
その後、内部のヒーターに通電して加熱を開始する等の
手順で使用される。本発明の重要な点は、樹脂発泡体調
整時の整泡剤として、汎用されるノニオン系界面活性剤
とともにアニオン系界面活性剤を併せ用いることにあ
る。樹脂発泡体調整は熱硬化性樹脂、発泡剤、硬化剤及
び整泡剤を用いて行われる。使用する樹脂としては、熱
硬化性樹脂、特に好ましくはレゾール型フェノール樹脂
が用いられるが必ずしもこれに限定されない。発泡剤と
しては、プロパン等の炭化水素或いはクロロホルム等の
ハロゲン化炭化水素等の公知の気化性発泡剤が用いられ
る。硬化剤としては、塩酸等の無機酸或いはベンゼンス
ルホン酸等の有機酸等公知のものが単一或いは混合して
用いられる。整泡剤としては、汎用的なポリオキシエチ
レンヒマシ油等のノニオン系界面活性剤とともに、ドデ
シルベンゼンスルホン酸ナトリウム等のアルキル置換ベ
ンゼンスルホン酸ナトリウム又はアルキルジフェニルエ
ーテルジスルホン酸ナトリウム等の高級アルコール硫酸
エステル塩等のアニオン系界面活性剤を併せ用いる。具
体的には、配合比率として樹脂１００重量部に対し、発
泡剤、及び硬化剤をそれぞれ０．０１重量部乃至５０重
量部を、更に整泡剤としてノニオン系界面活性剤０．０
１重量部乃至２０重量部とともにアニオン系界界面活性
剤０．０１重量部乃至５０重量部を、同時にもしくは逐
次添加、混合攪拌し、得られたクリーム状の物を保温さ
れた金型内等に供給し発泡、硬化させることにより樹脂
発泡体を得ることができる。整泡剤としては、一般的に
は脂肪族アミン等のカチオン系界面活性剤或いはポリオ
キシエチレンヒマシ油等のノニオン系界面活性剤が用い
られる。樹脂発泡材調製時において稀にアニオン系界面
活性剤が用いられることもあるが、少なくともノニオン
系界面活性剤とアニオン系界界面活性剤とを併用して炭
化、又は黒鉛化した、真空炉用断熱材として供される多
孔質炭素材調製用としては例をみない。The present invention will be described in detail below. The heat insulating material for a vacuum furnace used in the present invention is made of a porous carbon material, which is formed by foaming and curing a resin to obtain a resin foam, which is not melted at a temperature of 2,000 ° C to 3,000 ° C. It is obtained by carbonizing or graphitizing in an active gas atmosphere or in vacuum, but it is more preferable to carbonize or graphitize at a temperature higher than the maximum operating temperature of the vacuum furnace in which it is used. The porous carbon material thus obtained is attached to the inner wall of the vacuum furnace as a heat insulating material. The vacuum furnace puts the material to be heated in it, then seals it and degasses it with a vacuum pump.
After that, the heater is used by energizing the internal heater to start heating. An important point of the present invention is to use an anionic surfactant together with a widely used nonionic surfactant as a foam stabilizer during resin foam preparation. The resin foam is prepared by using a thermosetting resin, a foaming agent, a curing agent and a foam stabilizer. As the resin used, a thermosetting resin, particularly preferably a resol type phenol resin is used, but the resin is not limited to this. As the foaming agent, a known vaporizable foaming agent such as a hydrocarbon such as propane or a halogenated hydrocarbon such as chloroform is used. As the curing agent, known ones such as an inorganic acid such as hydrochloric acid or an organic acid such as benzenesulfonic acid may be used alone or in combination. Examples of the foam stabilizer include nonionic surfactants such as general-purpose polyoxyethylene castor oil, and alkyl-substituted sodium benzenesulfonate such as sodium dodecylbenzenesulfonate or higher alcohol sulfate such as alkyldiphenyl ether disulfonate. The anionic surfactant of is also used. Specifically, as a compounding ratio, 0.01 to 50 parts by weight of each of a foaming agent and a curing agent are added to 100 parts by weight of a resin, and a nonionic surfactant as a foam stabilizer is 0.0
0.01 parts by weight to 50 parts by weight of an anionic surface active agent together with 1 part by weight to 20 parts by weight are added simultaneously or sequentially and mixed and stirred, and the obtained creamy product is placed in a heat-insulating mold or the like. A resin foam can be obtained by supplying, foaming, and curing. As the foam stabilizer, a cationic surfactant such as an aliphatic amine or a nonionic surfactant such as polyoxyethylene castor oil is generally used. Although rarely an anionic surfactant is used when preparing a resin foam material, at least a nonionic surfactant and an anionic surfactant are used in combination to carbonize or graphitize, and a vacuum furnace insulation There is no example for preparing a porous carbon material used as a material.
【０００７】整泡剤としてノニオン系界面活性剤とアニ
オン系界面活性剤とを併用して調製樹脂発泡体を炭化又
は黒鉛化した多孔質炭素材は、カチオン系或いはノニオ
ン系界面活性剤等を使用したものに比し、真空炉用断熱
材として用いた場合、真空脱気時間が著しく短縮される
優れた特性を示す。この作用機構については必ずしも明
確ではないが、脱気が微細気孔の連通部を介して行われ
る際に、ノニオン系界面活性剤とアニオン系界面活性剤
とを併用すると、カチオン系或いはノニオン系界面活性
剤等を使用したものに比し、多孔質炭素材の微細気孔の
連通の度合いが高く、従って脱気が容易に行われ脱気時
間が短縮されるものと考えられる。A porous carbon material obtained by carbonizing or graphitizing a resin foam prepared by using a nonionic surfactant and an anionic surfactant together as a foam stabilizer uses a cationic or nonionic surfactant. When used as a heat insulating material for a vacuum furnace, it exhibits excellent characteristics that the vacuum deaeration time is significantly shortened. The mechanism of this action is not always clear, but when deaeration is carried out through the communication part of fine pores, if a nonionic surfactant and an anionic surfactant are used together, a cationic or nonionic surfactant is used. It is considered that the degree of communication of the fine pores in the porous carbon material is higher than that in the case where the agent or the like is used, and therefore deaeration is easily performed and the deaeration time is shortened.
【０００８】[0008]
【実施例】以下に本発明の具体的な実施例を説明する。 実施例１ レゾール型フェノール樹脂１００重量部に発泡剤として
ペンタン４重量部を、硬化剤としてパラトルエンスルホ
ン酸１５重量部を、整泡剤としてヒマシ油系エチレンオ
キサイド付加物（第一工業製薬製レジノールＦ−１２
０）３重量部及びドデシルベンゼンスルホン酸ナトリウ
ム５重量部を、混合し発泡させ、４５℃、５０分間で硬
化させた。得られた発泡体を不活性ガス雰囲気中、２５
００℃で黒鉛化した。得られた多孔質炭素材の嵩密度は
０．０９ｇ／ｃｃであった。この多孔質炭素材から１０
０ｍｍ×１００ｍｍ×６０ｍｍのブロックを切りだし、
真空容器に入れ、真空脱気時間を測定した。尚、真空ポ
ンプは日本真空社製ＰＶＤ３６０を用いた。 実施例２ 整泡剤としてヒマシ油系エチレンオキサイド付加物（第
一工業製薬製レジノールＦ−１２０）３重量部及びドデ
シルベンゼンスルホン酸ナトリウム２０重量部を用いる
他は、実施例１と同様の条件で多孔質炭素材を調製し、
嵩密度０．０９ｇ／ｃｃの多孔質炭素材を得た。そのも
のについて実施例１と同様の条件により真空脱気時間を
測定した。EXAMPLES Specific examples of the present invention will be described below. Example 1 100 parts by weight of a resol type phenol resin, 4 parts by weight of pentane as a foaming agent, 15 parts by weight of paratoluenesulfonic acid as a curing agent, and an ethylene oxide adduct of castor oil as a foam stabilizer (resinol manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.). F-12
0) 3 parts by weight and 5 parts by weight of sodium dodecylbenzenesulfonate were mixed and foamed, and cured at 45 ° C. for 50 minutes. The foam obtained was placed in an inert gas atmosphere, and
Graphitized at 00 ° C. The bulk density of the obtained porous carbon material was 0.09 g / cc. 10 from this porous carbon material
Cut out a block of 0 mm x 100 mm x 60 mm,
It was placed in a vacuum container and the vacuum deaeration time was measured. The vacuum pump used was PVD 360 manufactured by Nippon Vacuum Co., Ltd. Example 2 Under the same conditions as in Example 1 except that 3 parts by weight of a castor oil-based ethylene oxide adduct (resinol F-120 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and 20 parts by weight of sodium dodecylbenzenesulfonate were used as a foam stabilizer. Prepare a porous carbon material,
A porous carbon material having a bulk density of 0.09 g / cc was obtained. The vacuum deaeration time was measured for the sample itself under the same conditions as in Example 1.
【０００９】比較例として、整泡剤としてヒマシ油系エ
チレンオキサイド付加物（第一工業製薬製レジノールＦ
−１２０）８重量部を用いる他は、実施例と同様の条件
により調製し嵩密度０．０９ｇ／ｃｃの多孔質炭素材を
得た。そのものについて実施例と同様の条件により真空
脱気時間を測定した。これらの結果を表１に示す。As a comparative example, a castor oil type ethylene oxide adduct as a foam stabilizer (resinol F manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
-120) A porous carbon material having a bulk density of 0.09 g / cc was prepared by the same conditions as in Example except that 8 parts by weight was used. The vacuum degassing time was measured for the sample itself under the same conditions as in the examples. The results are shown in Table 1.
【００１０】[0010]
【表１】 [Table 1]
【００１１】[0011]
【発明の効果】樹脂発泡体を炭化、又は黒鉛化して真空
炉用断熱材を製造するに際し、原料として供する樹脂発
泡体調製時に整泡剤としてノニオン系界面活性剤とアニ
オン系界面活性剤とを併用した本発明による断熱材は、
整泡剤として単にノニオン系又はカチオン系界面活性剤
のみを用いた断熱材に比べ脱気性能が著しく改善され
る。EFFECT OF THE INVENTION When carbonizing or graphitizing a resin foam to produce a heat insulating material for a vacuum furnace, a nonionic surfactant and an anionic surfactant are used as foam stabilizers when preparing a resin foam to be used as a raw material. The heat insulating material according to the present invention used in combination,
The degassing performance is remarkably improved as compared with a heat insulating material using only a nonionic or cationic surfactant as a foam stabilizer.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 平山 正士 福岡県北九州市小倉北区中井４−７−７− 101 (72)発明者 岡田 克美 宮城県志田郡鹿島台町広長字尻掛杉乃崎27 −８ ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masashi Hirayama 4-7-7-101 Nakai, Kokurakita-ku, Kitakyushu, Fukuoka Prefecture 72 (72) Katsumi Okada Hiroshiji Suginokazaki, Hirokage, Kashimadai-cho, Shida-gun, Miyagi Prefecture 27- 8
Claims (3)
を用いて調製した樹脂発泡体を２，０００℃以上で炭化
又は黒鉛化して真空炉用断熱材を製造するに際し、樹脂
発泡体調製時の整泡剤としてノニオン系界面活性剤とア
ニオン系界面活性剤とを併せ用いることを特徴とする真
空炉用断熱材の製造方法。1. A resin foam produced by using a thermosetting resin, a foaming agent, a curing agent, and a foam stabilizer, is carbonized or graphitized at 2,000 ° C. or higher to produce a heat insulating material for a vacuum furnace. A method for producing a heat insulating material for a vacuum furnace, which comprises using a nonionic surfactant and an anionic surfactant together as a foam stabilizer during foam preparation.
ル樹脂を用いる請求項１記載の方法。2. The method according to claim 1, wherein a resol type phenol resin is used as the thermosetting resin.
換ベンゼンスルホン酸ナトリウム又は高級アルコール硫
酸エステル塩のうちのいずれかひとつを用いる請求項１
又は請求項２記載の方法。3. An alkyl-substituted sodium benzenesulfonate or a higher alcohol sulfate ester salt is used as the anionic surfactant.
Alternatively, the method according to claim 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5204714A JPH0733551A (en) | 1993-07-27 | 1993-07-27 | Production of heat insulating material for vacuum furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5204714A JPH0733551A (en) | 1993-07-27 | 1993-07-27 | Production of heat insulating material for vacuum furnace |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0733551A true JPH0733551A (en) | 1995-02-03 |
Family
ID=16495099
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5204714A Withdrawn JPH0733551A (en) | 1993-07-27 | 1993-07-27 | Production of heat insulating material for vacuum furnace |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0733551A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999065843A2 (en) * | 1998-05-22 | 1999-12-23 | Alliedsignal Inc. | Graphitizable foam preform |
| US6689295B2 (en) | 2000-03-23 | 2004-02-10 | Osaka Prefectural Government | Carbonaceous porous body and method for producing the same |
| WO2023181443A1 (en) * | 2022-03-25 | 2023-09-28 | 住友理工株式会社 | Thermal insulation material |
-
1993
- 1993-07-27 JP JP5204714A patent/JPH0733551A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6126874A (en) * | 1997-11-14 | 2000-10-03 | Alliedsignal Inc. | Process of making a graphitizable foam preform |
| WO1999065843A2 (en) * | 1998-05-22 | 1999-12-23 | Alliedsignal Inc. | Graphitizable foam preform |
| WO1999065843A3 (en) * | 1998-05-22 | 2000-02-24 | Allied Signal Inc | Graphitizable foam preform |
| US6689295B2 (en) | 2000-03-23 | 2004-02-10 | Osaka Prefectural Government | Carbonaceous porous body and method for producing the same |
| WO2023181443A1 (en) * | 2022-03-25 | 2023-09-28 | 住友理工株式会社 | Thermal insulation material |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4970741B2 (en) | High strength monolith carbon foam | |
| AU769769B2 (en) | Pitch based foam with particulate | |
| US6663842B2 (en) | Pitch-based carbon foam and composites | |
| JP2001261439A (en) | Carbonaceous foamed body and its production process | |
| CN101049928B (en) | Method for manufacturing high heat conducting foam material of graphite with even apertures | |
| CN114524674B (en) | Heat-proof, heat-insulation and load-bearing integrated light carbon-ceramic composite material and preparation method thereof | |
| JP2003509330A (en) | Casting method for pitch-based foam | |
| Kim et al. | Characteristics of a high compressive strength graphite foam prepared from pitches using a PVA–AAc solution | |
| JPH0733551A (en) | Production of heat insulating material for vacuum furnace | |
| CN114671674A (en) | Silicon dioxide foamed ceramic and preparation method thereof | |
| JP2015529269A (en) | Phenolic foam | |
| JP4878672B2 (en) | Foamable phenolic resole resin composition and method for producing the same | |
| CN111548183A (en) | Method for preparing graded porous silicon carbide ceramic by gel casting and carbothermic reduction | |
| RU2377223C1 (en) | Method to produce composite carbon materials | |
| JPH11217278A (en) | Production of porous body of activated carbon | |
| JPH1072266A (en) | Porous glassy carbon and its production | |
| KR100673432B1 (en) | Method for preparation of a carbon composite containing carbon nanotube | |
| JPH04349178A (en) | Low density porous carbon body and production thereof | |
| KR20210146932A (en) | Method for producing porous carbon material and porous carbon material obtainable by the method | |
| JPS62132714A (en) | Production of porous carbonaceous material | |
| JPH03205383A (en) | Production of porous carbon material | |
| JPH0633195B2 (en) | Carbon foam insulation molded article and method for producing the same | |
| JPH07315931A (en) | Carbon material for ion implantation member and production thereof | |
| JPS6036316A (en) | Preparation of porous carbon material | |
| JPS62132715A (en) | Production of porous carbon material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Application deemed to be withdrawn because no request for examination was validly filed |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20001003 |