JPH0633195B2 - Carbon foam insulation molded article and method for producing the same - Google Patents
Carbon foam insulation molded article and method for producing the sameInfo
- Publication number
- JPH0633195B2 JPH0633195B2 JP61140959A JP14095986A JPH0633195B2 JP H0633195 B2 JPH0633195 B2 JP H0633195B2 JP 61140959 A JP61140959 A JP 61140959A JP 14095986 A JP14095986 A JP 14095986A JP H0633195 B2 JPH0633195 B2 JP H0633195B2
- Authority
- JP
- Japan
- Prior art keywords
- foam
- carbon
- fiber
- molded body
- resin
- 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 - Lifetime
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Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は炭素系発泡断熱成形体およびその製造方法に関
し、特に本発明は発泡体内部本体と同質の炭化収縮率を
有する炭素質又は黒鉛質の前駆体の被膜が形成され、発
泡成形体本体と被膜とが一体化となっていることより、
成形体自体の強度が補強され、かつ不浸透性が向上した
炭素系発泡断熱成形体およびその製造方法に関する。TECHNICAL FIELD The present invention relates to a carbon-based foamed heat insulating molded article and a method for producing the same, and in particular, the present invention relates to a carbonaceous or graphite material having a carbonization shrinkage ratio similar to that of a foam inner body. Since the precursor film of is formed, and the foamed molded body and the film are integrated,
TECHNICAL FIELD The present invention relates to a carbon-based foamed heat insulating molded article in which the strength of the molded article itself is reinforced and the impermeability is improved, and a method for producing the same.
従来よりフェノール樹脂及びポリウレタン樹脂などの熱
硬化性樹脂のプラスチック発泡体は古くから数多くの提
案がなされており、その長所として軽量性、断熱性、吸
音性等に優れているため、広く断熱材、防音材、緩衝材
等の用途面で使用されている。しかしながらフェノール
樹脂等の上記発泡体は、耐熱性には優れているものの、
断熱性は２００〜２５０℃を越えないので耐高熱の断熱
材とはいえず、また有機系樹脂組成であるがために耐薬
品性が十分でなく老化し易い欠点があるばかりではな
く、強度が弱く脆性を有するなどの欠点がある。Conventionally, many proposals have been made for plastic foams of thermosetting resins such as phenolic resins and polyurethane resins, and their advantages include light weight, heat insulation, sound absorption, etc. It is used in applications such as soundproofing materials and cushioning materials. However, although the above foam such as phenol resin has excellent heat resistance,
The heat insulation does not exceed 200 to 250 ° C, so it cannot be said that it is a high heat resistant heat insulating material. Moreover, since it is an organic resin composition, it has not only the drawbacks of insufficient chemical resistance and easy aging, but also strength. It has weaknesses such as weakness and brittleness.
そのため、これらの欠点を除去・改善すべくフェノール
樹脂等の発泡体を炭化した炭素質発泡体が提案され、耐
熱性、耐薬品性などの諸性質の向上が試みられている。Therefore, in order to eliminate or improve these defects, a carbonaceous foam obtained by carbonizing a foam such as phenol resin has been proposed, and attempts have been made to improve various properties such as heat resistance and chemical resistance.
例えば、フェノール樹脂又はポリウレタン樹脂の発泡体
を非酸化性雰囲気下で焼成することにより炭素質発泡体
を得る方法として、特開昭５９−９７５１１号公報、特
公昭６０−５９１６８号公報及び特公昭６０−５９１６
９号公報により提案された炭素構造物又は炭素多孔体の
製造法がある。For example, as a method for obtaining a carbonaceous foam by firing a foam of a phenol resin or a polyurethane resin in a non-oxidizing atmosphere, JP-A-59-97511, JP-B-60-59168 and JP-B-60 are available. -5916
There is a method for producing a carbon structure or a carbon porous body proposed by Japanese Patent Publication No.
これらの方法により得られる発泡体は一般に開放気孔の
ものよりも独立気泡のものの方がはるかに断熱性が良好
であり、また発泡倍率が大きい方が密度は小さくなり断
熱特性も良くなる。そして同じ発泡倍率であるならば炭
素化収率が低い方が断熱性は良好となるが密度が小さく
なるほど強度は低下し、また気泡不浸透性も低下する。The foams obtained by these methods generally have much better heat insulating properties than those having open pores, and those having a larger expansion ratio have smaller density and better heat insulating properties. If the expansion ratio is the same, the lower the carbonization yield is, the better the heat insulating property is, but the lower the density is, the lower the strength is, and the cell impermeability is also decreased.
ところで、フェノール樹脂又はウレタン樹脂発泡体を炭
化する際には三次元方向に収縮すると共に、揮発分を放
出して重量が減少する。そして、熱処理により炭素以外
の原子の存在が認められなくなるためには、一般に１０
００〜１５００℃の温度が必要であり、特にフェノール
樹脂の場合には１３００〜１５００℃の温度が必要であ
る。By the way, when a phenol resin or urethane resin foam is carbonized, it shrinks in a three-dimensional direction and releases volatile matter to reduce its weight. In order to prevent the presence of atoms other than carbon from being recognized by heat treatment, it is generally 10
A temperature of 00 to 1500 ° C. is required, and particularly in the case of a phenol resin, a temperature of 1300 to 1500 ° C. is required.
また、フェノール樹脂は低い炭素化収縮率を有している
ため、この段階では比較的大きな収縮を示し、この段階
のものは炭素質と呼ばれている。Further, since the phenol resin has a low carbonization shrinkage, it shows a relatively large shrinkage at this stage, and that at this stage is called carbonaceous.
これに対し、１８００〜２０００℃以上の温度で熱処理
すると炭素原子間に結晶化に伴う構造変化が起こる段階
があり、この段階のものは黒鉛質と呼ばれている。しか
し、有機化合物のうち炭素化後の熱処理により、結晶化
すなわち黒鉛化し易い有機化合物とそうでない有機化合
物とがある。フェノール樹脂又はフラン樹脂等は後者に
属するもので難黒鉛化炭素と呼ばれており、このものは
ガス不浸透性を有していることからガラス状炭素と呼ば
れている。この種の炭素となる有機化合物には前述のよ
うにフェノール樹脂を初めとするフラン樹脂等の熱硬化
性樹脂がある。このような炭素化過程で溶融しない炭素
前駆体は、炭素化の段階で分子移動が著しく制約される
ため、芳香族平面は出来上がってもなかなか大きな層が
形成されにくい。また層の配合も起こりにくく、三次元
的な非整列構造を多く有する炭素となり易い。それゆ
え、フェノール樹脂又はフラン樹脂等の熱硬化性樹脂は
微細な閉気孔のユニットセル構造のガラス状のガス不浸
透性の被膜を形成し得る特徴を有している。On the other hand, when heat treatment is performed at a temperature of 1800 to 2000 ° C. or higher, there is a step in which a structural change occurs due to crystallization between carbon atoms, and this step is called graphite. However, among organic compounds, there are organic compounds that are easily crystallized, that is, graphitized by heat treatment after carbonization, and organic compounds that are not. Phenolic resins, furan resins, and the like belong to the latter and are called non-graphitizable carbon, and they are called glassy carbon because they have gas impermeability. As described above, there are thermosetting resins such as furan resin including phenol resin as the organic compound which becomes carbon of this kind. In such a carbon precursor that does not melt during the carbonization process, the molecular migration is significantly restricted at the carbonization stage, so that even if the aromatic plane is completed, it is difficult to form a large layer. In addition, the layers are less likely to be compounded and tend to become carbon having many three-dimensional non-aligned structures. Therefore, a thermosetting resin such as a phenol resin or a furan resin is characterized in that it can form a glass-like gas impermeable coating having a unit cell structure with fine closed pores.
ところが、このような被膜を発泡体の表層部に有しない
従来技術による発泡体を炭素化させたものは、その表面
から炭素粉が摩擦や外的衝撃によって剥離したり脱落し
易く、かつ圧縮強度は必ずしも十分なものとはいえない
現状である。そこで、このような問題点を解決するため
に、炭素質発泡体の表面にスキン層又は表皮と呼ばれる
被膜を形成した炭素質発泡体が提案されている。However, the carbonized foam according to the prior art which does not have such a coating on the surface layer of the foam has a tendency that carbon powder is easily peeled or dropped from the surface due to friction or external impact, and has a compressive strength. Is not always enough. Therefore, in order to solve such a problem, a carbonaceous foam in which a coating called a skin layer or a skin is formed on the surface of the carbonaceous foam has been proposed.
例えば、(1) 特開昭５０−５０４７１号公報の発明によ
れば、発泡速度と硬化速度とを制御して、これらの速度
差を内部と表面とに生じさせ、速度の遅い表面には比較
的緻密なスキン層が形成され、一方速度の早い内部には
発泡体が形成され、これらの密接性が良好で外観及び性
能の優れた発泡体が得られると開示されている。For example, according to the invention of (1) Japanese Patent Application Laid-Open No. 50-50471, the foaming speed and the curing speed are controlled to cause a speed difference between the inside and the surface, and a slow speed surface is compared. It is disclosed that a dense skin layer is formed, while a foam is formed in the inside of which the speed is high, and a foam having good closeness and excellent appearance and performance can be obtained.
また、(2) 特開昭５７−１７４０号公報の発明によれ
ば、原液のパック率及び発泡温度を特定範囲内に制御し
てボイドの発明の少ない表皮付き硬質ウレタンフォーム
成形体が得られると開示されている。Further, (2) according to the invention of Japanese Patent Laid-Open No. 57-1740, it is possible to obtain a hard urethane foam molded article with a skin having less void invention by controlling the pack rate and the foaming temperature of the undiluted solution within a specific range. It is disclosed.
一方、(3) 特開昭５７−４７６３５号公報の発明によれ
ば、酸性硬化剤、発泡剤、整泡剤などを含有した液状レ
ゾール型フェノール樹脂初期縮合物を予熱した密閉金型
内で発泡硬化させ、紙等と良好な接着性を示すスキン層
を発泡体表面に形成させたスキン付きフェノールフォー
ムが得られると開示されている。On the other hand, according to the invention of (3) JP-A-57-47635, a liquid resol-type phenol resin initial condensate containing an acidic curing agent, a foaming agent, a foam stabilizer is foamed in a closed mold preheated. It is disclosed that a phenolic foam with a skin can be obtained which is cured to form a skin layer having good adhesion to paper or the like on the surface of the foam.
しかしながら、上記(1) 及び(2) の発明は発泡倍率が大
きく表面スキン層と内部発泡体との炭素化に伴う収縮が
異なりその結果割れ易く、硬化速度の制御並びに温度制
御は極めて困難であり、また上記(3) の発明のように紙
等のセルローズ繊維からなるスキン層が形成されたもの
はフェノール樹脂等からなるスキン層が形成された発泡
体に比較して炭素化収率が低く、その結果、発泡体表面
のガス不浸透性は十分なものではなく表面層の脱落物や
剥離物の発生が起こり、表面層によって強度補強がされ
ていないために発泡体自体の強度も十分なものとはいえ
ないものである。However, in the inventions of (1) and (2) above, the expansion ratio is large and the shrinkage due to carbonization of the surface skin layer and the internal foam is different, resulting in cracking easily, and it is extremely difficult to control the curing speed and temperature. Further, as in the invention of the above (3), the one in which the skin layer made of cellulose fiber such as paper is formed has a lower carbonization yield as compared with the foam in which the skin layer made of phenolic resin is formed, As a result, the gas impermeability of the foam surface is not sufficient, and the surface layer may have fallen or exfoliated material, and the strength of the foam itself is not sufficient because the surface layer is not reinforced. That is not the case.
本発明は上記従来技術の欠点並びに未解決の問題点を除
去・改善することを目的とし、炭素化収率が２０重量％
（以下、単に％という）以上のフェノール樹脂、フラン
樹脂等の熱硬化性樹脂を用いて発泡体成形をつくり、そ
の表面部にもこれらの熱硬化性樹脂と同質の炭素化収縮
性を有する繊維状物からなる炭素前駆体の被膜を形成
し、これら表層部と内部の発泡成形体とを一体成形し、
さらに炭素化ないしは黒鉛化した炭素系発泡断熱材成形
体を提供することによって、前記目的を達成し従来技術
によっては付与することができなかったガス不浸透性と
強度等を改善した炭素系発泡断熱材成形体を提供するも
のである。The present invention aims to eliminate and improve the above-mentioned drawbacks and unsolved problems of the prior art, and the carbonization yield is 20% by weight.
A fiber which is made of a thermosetting resin such as phenol resin or furan resin (hereinafter simply referred to as “%”) and has the same carbonization shrinkage as those thermosetting resins on the surface thereof. Forming a coating film of a carbon precursor consisting of a shaped material, integrally molding the surface layer portion and the foam molding inside,
Further, by providing a carbonized or graphitized carbon-based foamed heat insulating material molded body, the carbon-based foamed heat insulating material which achieves the above-mentioned object and has improved gas impermeability and strength, which cannot be imparted by the prior art. A molded product is provided.
［問題点を解決するための手段および作用］ 本発明の炭素系発泡断熱成形体は，成形体の表層部には
該成形体の内部を構成する熱硬化性樹脂と同質の炭素化
収縮性を有する繊維状物からなる炭素前駆体の被膜が形
成されており，該成形体の内部には炭素化収率が２０重
量％以上の難黒鉛化性の熱硬化性樹脂の発泡体が形成さ
れており，これら表層部と内部の発泡体とが一体成形さ
れかつ炭素化又は黒鉛化されて成る炭素系発泡断熱成形
体であって， 前記繊維状物は不融化ポリアクリロニトリル繊維，不融
化ピッチ繊維，フェノール樹脂繊維あるいはフラン樹脂
繊維から成ることを特徴とする炭素系発泡断熱成形体で
ある。[Means and Actions for Solving Problems] The carbon foamed heat insulating molded article of the present invention has the same carbonization shrinkage as the thermosetting resin constituting the inside of the molded article in the surface layer portion of the molded article. A carbon precursor coating comprising a fibrous material is formed, and a non-graphitizable thermosetting resin foam having a carbonization yield of 20% by weight or more is formed inside the molded body. And a carbon-based foamed heat insulating molded article in which the surface layer portion and the internal foam are integrally molded and carbonized or graphitized, wherein the fibrous material is infusible polyacrylonitrile fiber, infusible pitch fiber, It is a carbon-based foamed heat insulating molded article characterized by comprising phenol resin fiber or furan resin fiber.
また，本発明の炭素系発泡断熱成形体の製造方法は，成
形体を形成する型としての容器内に，該容器の形状に相
応した繊維状物からなる炭素前駆体を載置し，この容器
内に炭素化収率が２０重量％以上の難黒鉛化性の熱硬化
性樹脂の発泡体原料を注入し，該容器内で前記熱硬化性
樹脂を発泡させ前記繊維状物からなる炭素前駆体と前記
成形体内部の発泡体とを一体化成形した後，炭素化する
炭素系発泡断熱成形体の製造方法であって， 前記繊維状物は前記発泡体原料を構成する熱硬化性樹脂
と同質の炭素化収縮性を有する不融化ポリアクリロニト
リル繊維，不融化ピッチ繊維，フェノール樹脂繊維ある
いはフラン樹脂繊維から成ることを特徴とする炭素系発
泡断熱成形体の製造方法である。Further, in the method for producing a carbon-based foam insulation molded article of the present invention, a carbon precursor made of a fibrous material corresponding to the shape of the container is placed in a container as a mold for forming the molded product, and this container is A carbon precursor composed of the fibrous material is prepared by injecting a foaming raw material of a non-graphitizable thermosetting resin having a carbonization yield of 20% by weight or more into the container and foaming the thermosetting resin in the container. A method for producing a carbon-based foamed heat insulating molded body, which comprises integrally molding and a foam inside the molded body, and then carbonizing, wherein the fibrous material is of the same quality as the thermosetting resin constituting the foam raw material. The method for producing a carbon-based foamed heat insulating molded article is characterized by comprising an infusible polyacrylonitrile fiber, an infusible pitch fiber, a phenol resin fiber, or a furan resin fiber having the carbonization shrinkage property.
すなわち、本発明の炭素系発泡断熱材成形体はフェノー
ル樹脂又はフラン樹脂等の炭素化収率が２０％以上の熱
硬化性樹脂でつくられており、また難黒鉛化性であるた
め、黒鉛化に伴う熱伝導率が大きくなることが避けられ
るので断熱材としての特性上好都合である。That is, the carbon foam insulation material of the present invention is made of a thermosetting resin such as a phenol resin or a furan resin having a carbonization yield of 20% or more, and is difficult to graphitize. Since it is possible to avoid an increase in the thermal conductivity due to the heat treatment, it is advantageous in terms of properties as a heat insulating material.
また、本発明の製造方法によれば成形体の内部を構成す
る熱硬化性樹脂と同質の炭素化収縮性を有する繊維状物
から成る炭素前駆体の被膜を形成して成形体内部の発泡
体の補強効果を図ると共に、繊維状の炭素前駆体の種類
や複合形態を多種多様に変化させ、また適宜に選択する
ことによつて、炭素化に伴う収縮を自由に制御して発泡
体表面に生ずるクラックやグレーズと呼ばれる割れを防
止することができる。このため、成形体内部の発泡体の
表層部のスキン被膜層との炭素化に伴う収縮を整合さ
せ、これら両者の剥離を完全に防止し併せて独立気泡体
の集合により優れたガス不浸透性と強度とを内部の発泡
体に付与することが可能となる利点がある。これは、主
として次に説明するような作用及び構成によって、この
ような優れた効果がもたらされるものと考えられる。Further, according to the production method of the present invention, a foamed body inside the molded body is formed by forming a coating film of a carbon precursor composed of a fibrous material having the same carbonization shrinkability as the thermosetting resin forming the inside of the molded body. In addition to enhancing the reinforcing effect of carbon fibrous precursors, various changes in the type and composite form of fibrous carbon precursor, and by selecting appropriately, shrinkage accompanying carbonization can be freely controlled and It is possible to prevent cracks that occur and cracks called glaze. Therefore, the shrinkage due to the carbonization with the skin coating layer on the surface layer of the foam inside the molded body is matched, the separation of these both is completely prevented, and the closed cell body has an excellent gas impermeability. There is an advantage that it is possible to impart the strength and the strength to the foam inside. It is considered that such an excellent effect is brought about mainly by the operation and configuration as described below.
まず、成形体内部の発泡体はレゾール型又はノボラック
型のフェノール樹脂、フラン樹脂、ジビニルベンゼン樹
脂などの炭素化収率が２０％以上の熱効果性樹脂であっ
て、難黒鉛化性の炭素前駆体からなりクローズドポアー
と呼ばれるミクロな独立気泡体の集合により断熱特性を
高め、さらにガラス状炭素のユニットセルが多数集合し
たものであって、黒鉛等の結晶体に比較して熱伝導率が
小さい断熱成形体がつくられるため両者の効果による断
熱性に優れると共に、成形体の表層部にもガラス状炭素
から成るスキン被膜層が形成されているため全体のガス
不浸透性が十来の炭素発泡体に比して格段と向上し、さ
らにまた表層部と内部の発泡体部とが一体成形されてい
るため従来のこの主の発泡体に比して強度が著しく増大
し、併せて収縮性の制御により表層部の緻密で密度が大
きい層と成形体内部の低密度で断熱特性に優れる発泡体
層とが完全に整合して一体成形されているため表面層に
割れや剥離又は表面からの脱落が生ぜず、成形体全体の
強度が増大する。そして、一体成形は従来のスキン層を
二次的な工程によって付加する発泡体の製造法に比して
製造コストも安価となり経済上も有利である。First, the foam inside the molded body is a heat-effective resin having a carbonization yield of 20% or more, such as a resol-type or novolac-type phenol resin, a furan resin, or a divinylbenzene resin. It is a body made of closed micropores called closed pores, which enhances the heat insulation properties, and a large number of glassy carbon unit cells that have a lower thermal conductivity than crystalline materials such as graphite. Since a heat-insulating molded body is produced, both effects are excellent in heat insulation, and a skin film layer made of glassy carbon is also formed on the surface layer of the molded body, so the overall gas impermeability is carbon foam. Compared to the body, it is significantly improved, and since the surface layer and the internal foam part are integrally molded, the strength is significantly increased compared to this conventional main foam, and the shrinkability is also increased. Due to the control, the dense and high-density surface layer and the foam layer with low density and excellent heat insulating properties inside the molded body are perfectly aligned and integrally molded, so the surface layer is cracked, peeled, or dropped from the surface. Does not occur, and the strength of the entire molded body increases. Further, the integral molding is economically advantageous because the manufacturing cost is lower than that of the conventional foam manufacturing method in which a skin layer is added by a secondary process.
なお、本発明で使用される炭素前駆体としての繊維状物
とは、例えば２０％前後の線収縮を起こす繊維状の不融
化ピッチ又はフェノール樹脂などを不織布状又は織布状
にしたもの並びに長短の繊維そのものなどの各種形態の
ものをいう。すなわち、前記繊維状物は不融化ポリアク
リロニトリル繊維、不融化ピッチ繊維、フェノール樹脂
繊維、フラン樹脂繊維から選ばれる一種又は二種以上の
組合せからなり、その形態は短繊維状、長繊維状、織布
状、不織布状の少なくともいずれかの状態のものであ
る。具体的には、炭素化収率が２０％以上のフェノール
樹脂、フラン樹脂等の熱硬化性樹脂のファイバー又はこ
のファイバーと同質の樹脂との複合体、ピッチやＰＡＮ
などの不融化繊維及びこの繊維と前記熱硬化性樹脂との
複合体などを挙げることができる。The fibrous material as a carbon precursor used in the present invention means, for example, a fibrous infusible pitch or a phenolic resin which causes a linear shrinkage of about 20% in a non-woven fabric or a woven fabric, and long and short It refers to various forms such as the fiber itself. That is, the fibrous material consists of infusible polyacrylonitrile fiber, infusible pitch fiber, phenol resin fiber, or a combination of two or more kinds selected from furan resin fiber, and the form thereof is short fibrous, long fibrous, woven. It is in a cloth-like or non-woven cloth-like state. Specifically, a fiber of thermosetting resin such as phenol resin or furan resin having a carbonization yield of 20% or more, a composite of the fiber and a resin of the same quality as the fiber, pitch or PAN.
And the like, and a complex of the fiber and the thermosetting resin.
次に、本発明の前記成形体の内部を構成する熱硬化性樹
脂からなる発泡体の炭素化又は黒鉛化された成形体の嵩
密度は、０．０１〜０．２ｇ／cm3であることを特徴と
するものである。Next, the bulk density of the carbonized or graphitized molded body of the foam made of the thermosetting resin that constitutes the inside of the molded body of the present invention is 0.01 to 0.2 g / cm 3. It is characterized by.
このように嵩密度を０．０１〜０．２ｇ／cm3とする理
由は、この範囲においては一般的に発泡体の炭素化収縮
は一定であり、さらに炭素化収率と収縮とがバラスして
おり、炭素化前後の密度が殆ど一定となるため、表層部
の収縮率と整合し易くなるためである。しかしながら、
一般に炭素化もしくは黒鉛化した断熱用発泡体の嵩密度
はそれ自体の強度及び熱伝導率との関係から０．１ｇ／
cm3前後から０．２ｇ／cm3位が最適であると考えられて
いるが、本発明では前述のように主としてガラス状炭素
から成る表層部のスキン被膜と内部の発泡体とが一体同
時成形され強固に結合されているため、内部が０．１〜
０．０１ｇ／cm3の比較的低密度の発泡体であっても表
層部の強固で緻密な不浸透性のスキン被膜によって強度
が補強されているので断熱特性上更に有利な低密度の発
泡成形であってもよいのである。The reason why the bulk density is 0.01 to 0.2 g / cm 3 is that the carbonization shrinkage of the foam is generally constant in this range, and further the carbonization yield and the shrinkage vary. This is because the density before and after carbonization is almost constant, and it is easy to match the shrinkage rate of the surface layer portion. However,
Generally, the bulk density of a carbonized or graphitized heat insulating foam is 0.1 g / percent due to its own strength and thermal conductivity.
cm 3 While 0.2 g / cm 3 of the front and rear are considered optimal, integral molded simultaneously and skin coating of the surface layer portion made of glassy carbon primarily as mentioned above and the internal foam in the present invention The inner part is
Even if the foam has a relatively low density of 0.01 g / cm 3, the strength is reinforced by the strong and dense impermeable skin coating on the surface layer, so the foam molding with a low density is more advantageous in terms of heat insulation properties. May be.
このように、フェノール樹脂やフラン樹脂等の高炭素化
収率の熱硬化性樹脂により本体内部の発泡体とその表層
に同質の被膜を形成したものは、従来の発泡フェノール
樹脂のように他の発泡プラスチックに比して火災時にお
いて最も安全な材料であり、耐熱性、耐炎性、耐薬品
性、耐熱性及び遮音性に優れていると共に、特に同質の
樹脂組成からなる強固な表皮が形成されているため不浸
透性が著しく向上し、しかも発泡体全体の強度が著しく
向上し、表皮が本体内部の発泡体の強度を補強する効果
があらわれる。それゆえ、上記熱硬化性樹脂発泡体の嵩
密度が０．０１〜０．２ｇ／cm3であることが最も好ま
しい密度となる。このことは、前記発泡体が形成され、
かつその表層に同質の樹脂組成からなる表皮が形成され
た後に、１０００〜１５００℃の熱処理を受けて、まず
全体が炭素化し、その結果、２０００〜３０００℃に十
分耐え得る炭素質発泡断熱成形体がつくられることによ
り従来の表皮を有しない炭素質発泡体のように表面部分
の炭素が剥離したり、耐圧縮性に乏しいものと異なり、
ガス不浸透性や発泡体全体の強度が著しく向上すること
になる。したがって、本発明の炭素質発泡断熱成形体
は、従来の炭素質材料のように空孔、空洞や微細な亀裂
（ポアーやボイドやクラック）が多数存在しているため
ガス不浸透性ぬ優れず、それゆえに耐酸化性や強度が劣
るものとは異なり、表層部に形成された強固で緻密な被
膜によって、不浸透性が向上しかつ成形体の内部本体で
ある嵩密度が０．０１〜０．２ｇ／cm3位の発泡体部分
の強度を補強し全体として強度が大きくなる。したがっ
て、本発明によれば機械強度に優れかつ不浸透性の優れ
た炭素質発泡断熱成形体を提供することができるのであ
る。In this way, the foamed material inside the main body and the one with the same quality film formed on the surface layer of the thermosetting resin with a high carbonization yield such as phenolic resin or furan resin can be used as a conventional foamed phenolic resin. Compared to foamed plastic, it is the safest material in case of fire and has excellent heat resistance, flame resistance, chemical resistance, heat resistance, and sound insulation, and in particular forms a strong skin made of the same resin composition. Therefore, the impermeability is remarkably improved, the strength of the foam as a whole is remarkably improved, and the skin has the effect of reinforcing the strength of the foam inside the main body. Therefore, it is most preferable that the thermosetting resin foam has a bulk density of 0.01 to 0.2 g / cm 3 . This means that the foam is formed,
And, after a skin made of a resin composition of the same quality is formed on the surface layer thereof, it is subjected to a heat treatment at 1000 to 1500 ° C. to first carbonize the whole and, as a result, a carbonaceous foam insulation molded article that can sufficiently withstand 2000 to 3000 ° C. Unlike the conventional carbonaceous foams that do not have a skin, carbon on the surface part peels off or is poor in compression resistance due to the formation of
The gas impermeability and the strength of the entire foam will be significantly improved. Therefore, the carbonaceous foam insulation molded article of the present invention has many pores, cavities, and fine cracks (pores, voids, and cracks) like the conventional carbonaceous materials, and therefore is not gas impermeable. Therefore, unlike the one having poor oxidation resistance and strength, the strong and dense coating formed on the surface layer improves impermeability and the bulk density of the inner body of the molded product is 0.01 to 0. Strengthens the foam part at about 2 g / cm 3 to increase the strength as a whole. Therefore, according to the present invention, it is possible to provide a carbonaceous foam insulation molded article having excellent mechanical strength and excellent impermeability.
本発明の炭素系発泡断熱成形体なる名称は、前者の主と
して１０００〜１５００℃位の比較的低温域の熱処理に
よってつくられる炭素質発泡体と、後者の主として２０
００〜３０００℃位の比較的高温域の加熱処理によって
つくられる黒鉛質発泡体の総称であることを意味し、さ
らには半導体製造分野におけるシリコン単結晶引き上げ
装置、すなわちチョクラルスキー法（ＣＺ族）のシリコ
ン単結晶を製造するための加熱装置における炉の断熱材
や、アニール炉、真空炉などの雰囲気や被加熱処理物中
に微量の不純物の混入も全く許されない炉或いは金属蒸
着用装置の断熱材として最適であることから、上記名称
に更に断熱なる語を加えて、結局、炭素系発泡断熱成形
体と称するように、優れた断熱特性を有し、かつ表層が
強固で緻密であるがために不浸透性と強度が大なるがゆ
えに、被処理物に対するパーティクルなどの不純物の発
生を防止できる特徴を有するものである。The name of the carbon foamed heat insulating molded article of the present invention is mainly the former carbonaceous foam made by heat treatment in a relatively low temperature range of about 1000 to 1500 ° C. and the latter mainly 20.
This is a general term for graphitic foams produced by heat treatment in a relatively high temperature range of about 00 to 3000 ° C., and further, a silicon single crystal pulling apparatus in the semiconductor manufacturing field, that is, the Czochralski method (CZ group). Insulation material for furnaces used in the heating equipment for manufacturing silicon single crystals, and for the furnaces and metal deposition equipments where it is completely permissible to mix trace impurities into the atmosphere of the annealing furnace, vacuum furnace, etc. Since it is optimal as a material, the term “heat insulation” is added to the above name, and as a result, it has excellent heat insulation properties and has a strong and dense surface layer, as it is called a carbon-based foam insulation molding. In addition, since it has high impermeability and high strength, it has a feature that it is possible to prevent the generation of impurities such as particles to the object to be processed.
このように、本発明の炭素系発泡断熱成形体は、本体の
内部発泡成形体部分の嵩密度が０．０１〜０．２ｇ／cm
3であるため、熱伝導率は０．０１〜０．０ｋｃａｌ／
ｍ・ｈｒ・℃と比較的小さく優れた断熱性をもたらすと
共に、軽量でかつ、表層部にガラス状炭素質被膜又は黒
鉛質被膜が形成されたものであるため強度と気体不浸透
性と不純物発生率とが特に従来の炭素質発泡体よりも向
上し、著しく異なる特性を有する炭素質発泡体となる。As described above, the carbon foamed heat insulating molded article of the present invention has a bulk density of 0.01 to 0.2 g / cm 3 in the internal foamed molded article portion of the main body.
3 , the thermal conductivity is 0.01 to 0.0 kcal /
It has a relatively small m · hr · ° C and excellent heat insulation property, and is lightweight and has a glassy carbonaceous film or graphite film formed on the surface layer, so strength, gas impermeability and generation of impurities The rate is particularly improved over conventional carbonaceous foams, resulting in carbonaceous foams with significantly different properties.
そして、このような諸々のすぐれた特性を有する炭素系
発泡断熱成形体を製造する方法としては、たとうば、発
泡成形体を成形する型としての容器内に、該容器の形状
に相応した繊維状物からなる炭素前駆体を載置し、この
容器内に炭素化収率が２０重量％以上の熱硬化性樹脂の
発泡体原料を注入し、該容器内で熱硬化性樹脂発泡させ
前記繊維状物からなる炭素前駆体と成形体内部の発泡体
とを一体成形した後、炭素化又は黒鉛化することを特徴
とする炭素系発泡断熱成形体の製造方法を例示すること
ができる。And, as a method for producing a carbon-based foam insulation molded article having such various excellent properties, the method is as follows: in a container as a mold for molding the foamed molded product, a fiber corresponding to the shape of the container. A carbon precursor composed of a substance is placed, and a foaming raw material of a thermosetting resin having a carbonization yield of 20% by weight or more is injected into the container, and the thermosetting resin is foamed in the container to form the fiber. An example of the method for producing a carbon-based foamed heat-insulating molded article is characterized in that a carbon precursor made of a material and a foam inside the molded article are integrally molded and then carbonized or graphitized.
そして内部発泡体層は嵩比重が０．０１〜０．２ｇ／cm
3の熱硬化性樹脂発泡体で形成された後に、炭素化さら
には黒鉛化加熱処理によって、従来の炭素質発泡体とは
物性上及び形態上全く異なる複合発泡体を有利に製造す
ることができ、内部の発泡成形体は耐火断熱性を向上さ
せるために好都合な独立気泡体からなり、その表層部に
はガラス状の強固でガス等に対し不浸透性で不純物発生
がきわめて少ない炭素系発泡断熱成形体を有利に提供す
ることがだきる。なお、本発明の製造方法によれば、前
記成形体の内部と表層部とが同程度の炭素化収縮率を示
すので、成形体には形態上の歪みがすくなく、しかも従
来の炭素質発泡体と比較して高い密着性を示すことにな
る。また、内部の発泡体の嵩密度が０．０１〜０．２ｇ
／cm3の範囲内であれば内部発泡体自体の炭素化収縮率
は殆ど変化しない。そのため、表層部との収縮差は内部
発泡体の嵩密度に大小に左右されず、強固な炭素質又は
黒鉛質の発泡成形体を提供することができる。The internal foam layer has a bulk specific gravity of 0.01 to 0.2 g / cm.
After being formed from the thermosetting resin foam of 3 , it is possible to advantageously manufacture a composite foam that is completely different in physical properties and morphology from the conventional carbonaceous foam by carbonization and then graphitization heat treatment. The internal foam molding consists of closed cells, which is convenient for improving fire insulation, and its surface layer is a glass-like strong foam that is impervious to gases and has very few impurities. It is possible to advantageously provide a molded body. According to the production method of the present invention, since the inside of the molded body and the surface layer portion exhibit the same degree of carbonization shrinkage, the molded body has less morphological distortion, and the conventional carbonaceous foam Higher adhesion than that of The bulk density of the foam inside is 0.01 to 0.2 g.
Within the range of / cm 3 , the carbonization shrinkage of the internal foam itself hardly changes. Therefore, the difference in shrinkage with the surface layer does not depend on the bulk density of the internal foam, and a strong carbonaceous or graphite foamed article can be provided.
次に本発明の最も代表的な実施例について以下説明す
る。Next, the most typical embodiment of the present invention will be described below.
実施例１ 表面温度約５０℃に加熱した所定形状の金型内に、その
形状に相応するよう予めレゾール型フェノール樹脂を２
００重量％（以下、同様に重量％を単に％と記す）含浸
し、１３０℃でＢステージまで硬化乾燥した不融化ピッ
チファイバーからなる目付け坪量が４０ｇ／m2のシート
状物（ペーパー）を載置し、この金型内に市販のレゾー
ル型フェノール樹脂に発泡剤としてフレオンを１０ｐｈ
ｒ添加混合し、さらに硬化剤としてｐ−トルエンスルホ
ン酸を１０ｐｈｒ添加混合した混合物を素早く注入し
た。そして樹脂注入後に上記金型を８０℃に加熱して表
層に強固な被膜を有する嵩密度が０．０８ｇ／cm3のフ
ェノール樹脂発泡体を得た。次いで、この発泡体成形体
を還元性雰囲気中で昇温速度約２０℃／ｈｒにより約１
０００℃の加熱処理をして炭素化した後、さらに昇温速
度約５００℃／ｈｒにより２２００℃まで昇温して、２
２００℃１時間保持して、本発明１品を得た。Example 1 Into a mold having a predetermined shape heated to a surface temperature of about 50 ° C., a resol-type phenol resin was preliminarily used in an amount corresponding to the shape.
A sheet-like material (paper) having a basis weight of 40 g / m 2 made of infusible pitch fibers impregnated with 00% by weight (hereinafter, simply referred to as% by weight) and cured and dried at 130 ° C. to the B stage. Place it and put Freon as a foaming agent on a commercially available resole-type phenol resin in an amount of 10 ph in this mold.
A mixture of r-added and mixed and 10 phr of p-toluenesulfonic acid as a curing agent was rapidly injected. After injecting the resin, the mold was heated to 80 ° C. to obtain a phenol resin foam having a strong coating on the surface and having a bulk density of 0.08 g / cm 3 . Next, this foamed molded body is heated to about 1 at a heating rate of about 20 ° C./hr in a reducing atmosphere.
After carbonization by heat treatment at 000 ° C, the temperature is further raised to 2200 ° C at a heating rate of about 500 ° C / hr, and 2
The present invention 1 product was obtained by holding at 200 ° C. for 1 hour.
実施例２ 市販のカイノールファイバー（郡栄化学(株)製商品名）
にレゾール型フェノール樹脂を１９０％含浸し、Ｂステ
ージまで硬化乾燥したものを、所望の形状となるようテ
フロン製の型内に形状が相応するように仮内張りしてお
き、この中に市販のヘキサミン−ノボラック系発泡組成
物を入れ、その後マイクロ波照射によりテフロン製の型
ごと加熱処理して、平均嵩密度０．１ｇ／cm3で表層部
に厚さが１ｍｍの緻密な被膜（スキン層）を有するフェ
ノール樹脂発泡成形体を得た。次いで、この発泡体を非
酸化性雰囲気中で、昇温速度を約３０℃／ｈｒとして、
約１０００℃の加熱処理して炭素化した後、さらに１８
００℃のハロゲンガス雰囲気中で加熱処理し、炭素質発
泡成形体表面に存在する化学種としての不純物を除去す
べく脱灰処理した黒鉛質の本発明品２を得た。Example 2 Commercially available Kynol fiber (trade name, manufactured by Gunei Chemical Co., Ltd.)
The resin was impregnated with 190% of resole type phenolic resin, cured to the B stage and dried, and was temporarily lined in a Teflon mold so that the desired shape was obtained. -Incorporating a novolac-based foaming composition and then heat-treating it together with a Teflon mold by microwave irradiation to form a dense coating (skin layer) having an average bulk density of 0.1 g / cm 3 and a thickness of 1 mm on the surface layer portion. A phenol resin foam molding having the above was obtained. Then, the foam is heated in a non-oxidizing atmosphere at a temperature rising rate of about 30 ° C./hr,
After heat treatment at about 1000 ℃ to carbonize
A graphite-like product 2 of the present invention was obtained which was heat-treated in a halogen gas atmosphere at 00 ° C. and deashed to remove impurities as chemical species existing on the surface of the carbonaceous foam molded article.
実施例３ 実施例２により得た本発明品２を更に２０００℃のＳｉ
Ｏガス雰囲気中で熱処理し、黒鉛質発泡体成形体の表層
部をＳｉＯガスとの表面反応によりＳｉＯ軟化した本発
明品３を得た。Example 3 The product 2 of the present invention obtained in Example 2 was further subjected to Si at 2000 ° C.
Heat treatment was performed in an O 2 gas atmosphere to obtain a product 3 of the present invention in which the surface layer portion of the graphite foam molded body was SiO-softened by the surface reaction with SiO gas.
これらの本発明品を１〜３の主な諸性質を示すと下記第
１表の通りとなる。The main characteristics of these products of the present invention are shown in Table 1 below.
上記の表から明らかなように、本発明は従来の炭素質発
泡体と比較し、Ｈｅガス透過度が著しく低減し、ガス不
浸透性が向上したことが判る。また、圧縮強度は従来品
と比較して約１０倍程度増大しており、表層部の被膜に
よる強度補強効果が著しいことが判明した。また、熱伝
導率は従来品（黒鉛質発泡体）よりも小さいことから断
熱材としての断熱効果が向上していることも判る。さら
にまた、酸化重量減少率が従来品よりも１０分の１以下
に減少していることから、ガスによる酸化消耗が減少
し、ガス不浸透性の向上により酸化雰囲気での到達真空
度及び排気時間が著しく向上していることが明白であ
る。 As can be seen from the above table, the present invention has significantly reduced He gas permeability and improved gas impermeability as compared with conventional carbonaceous foams. In addition, the compressive strength was increased by about 10 times as compared with the conventional product, and it was found that the strength-enhancing effect of the coating on the surface layer was remarkable. Further, it can be seen that the heat conductivity as the heat insulating material is improved because the thermal conductivity is smaller than that of the conventional product (graphite foam). Furthermore, since the reduction rate of oxidized weight is less than 1/10 of that of conventional products, the oxidation consumption due to gas is reduced, and the gas impermeability is improved, and the ultimate vacuum and exhaust time in an oxidizing atmosphere are increased. Is clearly improved.
以上のように、本発明の炭素系発泡断熱成形体は表層部
に強固なガラス状被膜を有するためガス不浸透性が著し
く向上し、内部の嵩密度が低いものにあっても圧縮強度
は補強されて向上しており、独立気泡による断熱効果も
優れ、脱灰処理による不純物除去と表面層のＳｉＯ軟化
により、半導体製造用加熱炉の断熱材として最適のもの
を提供することができるので、当産業界において極めて
有用なものである。As described above, the carbon-based foam insulation molded article of the present invention has a strong glass-like coating on the surface layer, so that gas impermeability is significantly improved, and even if the internal bulk density is low, the compressive strength is reinforced. In addition, it is possible to provide the optimum heat insulating material for heating furnaces for semiconductor manufacturing by removing impurities by deashing and softening the SiO 2 surface layer. It is extremely useful in the industrial world.
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.5 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｂ２９Ｋ 105:04 ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 5 Identification code Internal reference number FI technical display location B29K 105: 04
Claims (2)
する熱硬化性樹脂と同質の炭素化収縮性を有する繊維状
物からなる炭素前駆体の被膜が形成されており，該成形
体の内部には炭素化収率が２０重量％以上の難黒鉛化性
の熱硬化性樹脂の発泡体が形成されており，これら表層
部と内部の発泡体とが一体成形されかつ炭素化又は黒鉛
化されて成る炭素系発泡断熱成形体であって， 前記繊維状物は不融化ポリアクリロニトリル繊維，不融
化ピッチ繊維，フェノール樹脂繊維あるいはフラン樹脂
繊維から成ることを特徴とする炭素系発泡断熱成形体。1. A coating of a carbon precursor composed of a fibrous material having the same carbonization shrinkage property as the thermosetting resin forming the inside of the molded body is formed on the surface layer of the molded body. A foam of a non-graphitizable thermosetting resin having a carbonization yield of 20% by weight or more is formed inside the molded body, and the surface layer portion and the foam inside thereof are integrally molded and carbonized. Or a graphitized carbon foam insulation, wherein the fibrous material is composed of infusible polyacrylonitrile fiber, infusible pitch fiber, phenol resin fiber or furan resin fiber. Molded body.
容器の形状に相応した繊維状物からなる炭素前駆体を載
置し，この容器内に炭素化収率が２０重量％以上の難黒
鉛化性の熱硬化性樹脂の発泡体原料を注入し，該容器内
で前記熱硬化性樹脂を発泡させ前記繊維状物からなる炭
素前駆体と前記成形体内部の発泡体とを一体化成形した
後，炭素化する炭素系発泡断熱成形体の製造方法であっ
て， 前記繊維状物は前記発泡体原料を構成する熱硬化性樹脂
と同質の炭素化収縮性を有する不融化ポリアクリロニト
リル繊維，不融化ピッチ繊維，フェノール樹脂繊維ある
いはフラン樹脂繊維から成ることを特徴とする炭素系発
泡断熱成形体の製造方法。2. A carbon precursor composed of a fibrous material corresponding to the shape of the container is placed in a container as a mold for forming a molded body, and the carbonization yield is 20% by weight or more in the container. The non-graphitizable thermosetting resin foam raw material is injected, and the thermosetting resin is foamed in the container to integrally form the carbon precursor composed of the fibrous material and the foam inside the molded body. A method for producing a carbon-based foamed heat insulating molded body, which is carbonized after chemical molding, wherein the fibrous material has infusible polyacrylonitrile having the same carbonization shrinkage as the thermosetting resin constituting the foam raw material. A method for producing a carbon-based foamed heat insulating molded article, which comprises a fiber, an infusibilized pitch fiber, a phenol resin fiber or a furan resin fiber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61140959A JPH0633195B2 (en) | 1986-06-16 | 1986-06-16 | Carbon foam insulation molded article and method for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61140959A JPH0633195B2 (en) | 1986-06-16 | 1986-06-16 | Carbon foam insulation molded article and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62297280A JPS62297280A (en) | 1987-12-24 |
| JPH0633195B2 true JPH0633195B2 (en) | 1994-05-02 |
Family
ID=15280794
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61140959A Expired - Lifetime JPH0633195B2 (en) | 1986-06-16 | 1986-06-16 | Carbon foam insulation molded article and method for producing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0633195B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6416639A (en) * | 1987-07-13 | 1989-01-20 | Nippon Catalytic Chem Ind | Vacuum insulating spacer and vacuum insulating structural body constituted by utilizing said spacer |
| WO2005070642A1 (en) * | 2004-01-20 | 2005-08-04 | Touchstone Research Laboratory, Ltd. | Carbon foam composite tooling and methods for using the same |
| JP6175315B2 (en) * | 2013-08-30 | 2017-08-02 | イビデン株式会社 | Manufacturing method of ceramic molded body |
| KR102179453B1 (en) * | 2018-09-20 | 2020-11-16 | (주)코멕스카본 | Manufacturing method of electrode for redox flow battery |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5641673B2 (en) * | 1972-07-04 | 1981-09-29 | ||
| JPS5997511A (en) * | 1982-11-24 | 1984-06-05 | I C Ii Kk | Carbonaceous structure and its manufacture |
-
1986
- 1986-06-16 JP JP61140959A patent/JPH0633195B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62297280A (en) | 1987-12-24 |
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