JPS6328475B2

JPS6328475B2 -

Info

Publication number: JPS6328475B2
Application number: JP56123592A
Authority: JP
Inventors: Takayuki Oda; Isao Kai; Setsuo Toyoshima; Michiharu Tanaka; Susumu Nagai
Original assignee: Asahi Kasei Kogyo KK
Current assignee: Asahi Kasei Corp
Priority date: 1981-08-08
Filing date: 1981-08-08
Publication date: 1988-06-08
Also published as: JPS58117212A

Description

【発明の詳細な説明】[Detailed description of the invention]

本発明は積層板の製造方法の改良に係り、更に
詳しくは湿式抄造成型して得られる樹脂内添抄造
シートの大幅な乾燥効率（生産性）の向上と、外
観、電気絶縁性、耐水性及び機械的特性等の物性
低下の防止との両立を可能とした積層板の製造方
法に関する。従来より、紙フエノール積層板の製造方法はパ
ルプ、コツトンリンター等の繊維性基材をあらか
じめ、叩解抄紙した原紙に、有機溶媒に溶解した
フエノール樹脂ワニスを含浸し、乾燥して溶媒を
除去したプリプレグを製造し、これを必要枚数積
層後、加熱加圧工程を経て、積層板とする方法が
使われている。近年では、上述のような、ワニス含浸工程の廃
止による省資源有機溶媒による危険性、臭気公害
の全く無い、新しい技術、すなわち、下述するよ
うな樹脂内添抄造方式が試みられている。該方法の工程の概略を述べるならば、水とパル
プ基材を叩解機を用いて分散した後、粉状フエノ
ール樹脂を撹拌機でよく分散せしめ、円網又は長
網抄紙機にて抄紙し、熱風又はホツトプレスで水
分を蒸発乾燥（加熱乾燥）させて、プリプレグを
製造し、これを更に加熱加圧成型して積層板を得
る方法である。しかしながら、樹脂内添抄造方式に於ける大き
な技術的問題点としては、通常市販されている粉
末フエノール樹脂を使用した場合、抄紙された樹
脂内添ウエツトシート中の水（沸点100℃）を蒸
発させるために、100℃以下で乾燥させた場合は、
非常に長時間の乾燥時間を要する。例えば80℃で
は160分の乾燥時間を要する。一方乾燥効率を高
めるために、乾燥温度を100℃以上にすると例え
ば120℃で乾燥すれば、乾燥時間は80分と短いが
樹脂の化学反応が進行して、樹脂の流れが悪くな
り、加熱加圧成型時の樹脂とパルプとの間に於け
るねれ不良を起し、いわゆる「かすれ」現象を生
じ、電気的特性、機械的特性及び耐水性が低下す
ることである。本発明者らは、樹脂内添抄造方式に於ける、か
かる乾燥効率（生産性）と物性を両立させるべく
鋭意研究した結果、特定の範囲内に調整した樹脂
特性（ゲルタイム、流動度）及び窒素含有量を有
する粉状アンモニアレゾール樹脂単独又はこの樹
脂を主体とする粉状フエノール樹脂を使用するこ
とにより、100℃以上の高温下で、非常に効率よ
く水分を乾燥させ得て、しかもその工程において
は、樹脂の反応を抑制し、最終工程での加熱加圧
によつて積層板を成型する時には「かすれ」現象
を起さずに、電気特性、耐水性及び機械的特性の
優れた積層板が得られることを見い出した。しか
しながら、本発明において新規に提供される粉状
フエノール樹紙を使用することの利点は、100℃
以上の高温下で乾燥する場合のみならず、100℃
以下の温度といえども従来の粉状フエノール樹脂
を用いる場合より高い温度で乾燥してなおかつ積
層板の特性の低下を防止する限りにおいて乾燥効
率が改良される点にも見い出され、また、たとえ
従来の粉末フエノール樹脂を用いる場合と同じ温
度で乾燥した場合でも樹脂の反応がより抑制され
るので後で加熱加圧成型するときの処理条件の自
由度が大きくなり、とりわけ高温領域での成型が
可能になる利点を有するものである。本発明の特許請求範囲に記載せる粉状フエノー
ル樹脂は、フエノール類とホルムアルデヒド類と
をアンモニア及び又はその誘導体の存在下におい
て温度が50〜120℃、好ましくは600〜100℃の条
件下で製造されるものでありかつ、窒素含有量が
3.3〜5.0重量％でゲルタイム120〜300秒、流動度
150〜230mmの範囲にあることを特徴とする粉状フ
エノール樹脂を含んで成る。窒素含有量が3.3重量％未満の場合は、抄紙工
程に於て、樹脂が、塊状物をつくらない程度ま
で、反応を進めたものについては、所望の樹脂特
性が得られ難くレゾールの熱硬化官能基数が多す
ぎて乾燥工程での熱安定性がないため、積層加工
時に「かすれ」現象を生じる一方所望の樹脂特性
にした場合は、粉状になり難く、抄紙工程に於
て、塊状物をつくり、実用に供し難い。一方、窒素含有量が、5.0重量％を越える場合、
レゾールの熱硬化性官能基数が少く、熱安定性に
優れるが、積層加工した場合、得られた積層板
は、電気特性、耐水性及び機械的特性が悪く、実
用に供し難い。ゲルタイムが120秒未満又は流動性が150mm未満
では、乾燥工程において高温乾燥してプリプレグ
を得た場合、積層加工時に「かすれ」現象を生
じ、一方「かすれ」現象を回避するために低温乾
燥した場合には、プリプレグの乾燥効率（生産
性）が著しく低下し、工業生産の場合の経済性を
大幅に損える。また、ゲルタイムが300秒、又は流動性が230mm
を越えると積層加工して得られる積層板の物性が
低下する傾向となり好ましくない。該粉状フエノール樹脂の製造に用いられるフエ
ノール類としては、フエノール又はその誘導体が
単独あるいは、任意の組合せで使用される。フエノール誘導体の例は、炭素数１〜６のアル
キル基を有するクレゾール、プロピルフエノー
ル、イソプロピルフエノール、ブチルフエノー
ル、ターシヤリーブチルフエノール等のアルキル
フエノール類中で好ましくは、メタ置換フエノー
ル類、ビスフエノール−Ａ、ビスフエノールＳ、
ビスフエノールＦ等フエノール２核体、レゾルシ
ノール等の多価フエノール類である。アルデヒド源としてはホルムアルデヒド、パラ
ホルムアルデヒド、アセトアルデヒド、グリオキ
ザール等を単独又は、混合して使用するが、最も
好ましくはホルマリンや、パラホルムアルデヒド
の形態のものである。窒素源としては、アンモニア及び又はその誘導
体としてヘキサメチレンテトラミン、モノエチル
アミン、トリエチルアミン等が用いられるが好ま
しくは、アンモニアやヘキサメチレンテトラミン
である。本発明に係る粉状フエノール樹脂には、従来の
固形アンモニアレゾール樹脂、固形アルカリレゾ
ール樹脂、ノボラツク樹脂等の樹脂のほか、従来
から一般的に使用されている任意の添加剤、例え
ばシランカツプリング剤、離型剤、界面活性剤な
どを、本発明の目的を損わない範囲で配合して使
用することができる。なお、本発明の積層板の製造いおけるプリプレ
グの加熱加圧成型は、特に限定するわけではない
が、一般に、120〜180℃、50〜200Kg／cm²の範囲
内の条件で行なう。以下、本発明品の使用の態様を含めて実施例に
より説明する。実施例１ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン1290ｇ、
28％アンモニア水250ｇを70℃で３時間反応さ
せた。これを65℃の温水1000ｇで水洗し、上澄
液を除去した後、反応物を水中へ投入し、冷却
固化せしめ、水中にて破砕し遠心分離機べ水切
りし、風乾して、固型のレゾール型樹脂を得
た。これを粉砕機で粉砕し粉状樹脂とした。こ
うして得た樹脂の特性は、ゲルタイム180秒、
流動度180mm、窒素含有量3.7％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造 300CSFに叩解されたLBKP100部に対し上記
粉末樹脂120部チエスト内で混合し、更に定着
剤としてカチオン性ポリアクリルアマイド0.4
部を添加してパルプにフエノール樹脂粉末を定
着させる。円網抄紙機にて常法抄紙法により抄き上げメ
ーキングロールにて積層した坪量2.2Kg／m²の
ウエツトシートを120℃の熱風乾燥機でおよそ
80分乾燥した。乾燥したプリプレグを150℃、
120Kg／cm²の成型条件で、60分間加熱加圧し厚
さ1.5mmの「かすれ」のない良好な積層板を得
た。実施例２実施例１(a)で得た粉状フエノール樹脂を使用
し、実施例１(b)と同様にしてウエツトシートを作
成した。この積層ウエツトシートをテフロンコー
テイングの離型処理を施したホツトプレス機にて
110℃、0.2Kg／cm²の条件下で、40分間乾燥した
後、150℃、120Kg／cm²のプレス条件で60分間加熱
加圧し、厚さ1.5mmの「かすれ」のない良好な積
層板を得た。積層板の特性を表−１に示す。実施例３ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン1290ｇ、
28％アンモニア水250ｇを90℃で１時間反応さ
せた後実施例１(a)と同様にして粉状とする。こ
の樹脂特性はゲルタイム210秒、流動度208mm、
窒素含有量3.7％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉末樹脂を使用し実施例１(b)と同様にし
て、厚さ1.5mmの「かすれ」のない良好な積層
板を得た。積層板の特性を表−１に示す。実施例４ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン1290部、
28％アンモニア水320ｇを70℃で４時間反応さ
せた後、実施例１(a)と同様にして粉状とする。
この樹脂の特性はゲルタイム300秒、流動度225
mm、窒素含有量4.5％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉状フエノール樹脂を使用し、実施例１
(b)と同様にして厚さ1.5mmの「かすれ」のない
良好な積層板を得た。積層板の特性を表−１に
示す実施例５ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン690ｇ、
ヘキサメチレンテトラミン100ｇを70℃で３時
間反応させた後実施例１(a)と同様にして粉状と
する。この樹脂特性はゲルタイム140秒、流動
度207mm、窒素含有量3.5％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉末樹脂を使用し、実施例１(b)と同様に
して厚さ1.5mmの「かすれ」のない良好な積層
板を得た。積層板の特性を表−１に示す。実施例６ (a) 粉状フエノール樹脂の製造フエノール900ｇ、メタクレゾール100ｇ、37
％ホルマリン850ｇ、28％アンモニア水250ｇを
70℃で３時間反応させた後、実施例１(a)と同様
にして粉状とする。この樹脂の特性はゲルタイ
ム130秒、流動度165mm、窒素量3.7％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉末樹脂を使用し、実施例１(b)と同様に
して厚さ1.5mmの「かすれ」のない良好な積層
板を得た。積層板の特性を表−１に示す。実施例７ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン950ｇ、
28％アンモニア水180ｇを60℃で、５時間反応
させた後、実施例１(a)と同様にして粉状とす
る。この樹脂の特性はゲルタイム130秒、流動
度164mm、窒素含有量3.4％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉末フエノール樹脂を使用し、実施例１
(b)と同様にして、厚さ1.5mmの「かすれ」のな
い、良好な積層板を得た。積層板の特性を表−
１に示す。実施例８ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン1290ｇ、
28％アンモニア水320ｇを90℃で１時間反応さ
せた後実施例１(a)と同様にして粉状とする。こ
の樹脂特性はゲルタイム260秒、流動度223mm、
窒素含有量4.5％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉末樹脂を使用し、実施例１(b)と同様に
して厚さ1.5mmの「かすれ」のない積層板を得
た。積層板の特性を表−１に示す。比較例１ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン2160ｇ、
28％アンモニア水70ｇを70℃で３間反応させた
後、実施例１(a)と同様にして粉状とするこの樹
脂特性はゲルタイム50秒、流動度48mm、窒素含
有量1.4％であつた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉末樹脂を使用して、実施例１(b)と同様
にして厚さ1.5mmの積層板を得たが、「かすれ」
を生じた、積層板の特性を表−１に示す。一方上記組成の粉末樹脂を用いても乾燥温度
を低く設定すれば、樹脂の反応進行が、おさえ
られるため良好な積層板を得ることができる。 120℃で乾燥した場合と80℃にて乾燥した場
合の積層板の状態を表−２にて比較した。80℃
にて乾燥した場合は「かすれ」も生ぜず良好で
あるが、乾燥時間が長時間要し、工業生産の場
合の経済性を大巾に損ねる結果となり本発明の
目的からはずれる。比較例２ (a) フエノール樹脂の製造フエノール1000ｇ、37％ホルマリン2160ｇ、
28％アンモニア水70ｇを70℃で1.5時間反応さ
せた後、実施例１(a)と同様にして得た樹脂特性
はゲルタイム145秒、流動度160mm、窒素含有量
1.4％であつたがこれは、室温で塊状になり、
粉状にならなかつた。そのため、上記樹脂は、フエノール樹脂内添
紙の製造に供すことは出来なかつた。比較例３ (a) 粉状フエノール樹脂の製造フエノール1000ｇ、37％1380部、28％アンモ
ニア水360ｇを70℃で３時間反応させた後実施
例１(a)と同様にして粉状とする。この樹脂はゲ
ルタイム340秒、流動度270mm窒素量5.3％であ
つた。 (b) フエノール樹脂内添紙の製造及び積層板の製
造上記粉末樹脂を使用し、実施例１(b)と同様に
して、厚さ1.5mmの積層板を得たが、電気的特
性が悪いものであつた。積層板の特性を表−１
に示す。 The present invention relates to improvements in the manufacturing method of laminates, and more specifically, to greatly improve the drying efficiency (productivity) of resin-added paper sheets obtained by wet paper forming and molding, and to improve the appearance, electrical insulation, and water resistance. The present invention also relates to a method for manufacturing a laminate that is compatible with prevention of deterioration of physical properties such as mechanical properties. Conventionally, the manufacturing method for paper phenol laminates has been to impregnate a base paper made from a fibrous base material such as pulp or cotton linter into beaten paper with a phenolic resin varnish dissolved in an organic solvent, and then dry it to remove the solvent. The method used is to manufacture prepreg, laminate the required number of sheets, and then heat and press them to form a laminate. In recent years, attempts have been made to develop a new technology that saves resources by eliminating the varnish impregnation process and is completely free from danger and odor pollution due to organic solvents, namely, the resin-added papermaking method described below. To outline the steps of this method, after dispersing water and pulp base material using a beater, powdered phenolic resin is well dispersed using a stirrer, and paper is made using a cylinder or Fourdrinier paper machine. In this method, moisture is evaporated and dried using hot air or a hot press (heat drying) to produce a prepreg, which is then further heated and pressure molded to obtain a laminate. However, a major technical problem in the resin-added papermaking method is that when commercially available powdered phenolic resin is used, water (boiling point 100°C) in the resin-added wet sheet that is made into paper is evaporated. However, if dried at below 100℃,
Requires very long drying time. For example, at 80°C, it takes 160 minutes to dry. On the other hand, in order to increase the drying efficiency, if the drying temperature is set to 100℃ or higher, for example, 120℃, the drying time will be as short as 80 minutes, but the chemical reaction of the resin will progress and the flow of the resin will become poor. This is due to poor twisting between the resin and the pulp during pressure molding, resulting in a so-called "fading" phenomenon, which deteriorates electrical properties, mechanical properties, and water resistance. As a result of intensive research to achieve both drying efficiency (productivity) and physical properties in the resin-added papermaking method, the present inventors have found that resin properties (gel time, fluidity) adjusted within a specific range and nitrogen By using powdered ammonia resol resin alone or powdered phenol resin mainly consisting of this resin, moisture can be dried very efficiently at high temperatures of 100°C or higher, and in the process. suppresses the reaction of the resin, and when the laminate is molded by heat and pressure in the final process, it does not cause the "fading" phenomenon and produces a laminate with excellent electrical properties, water resistance, and mechanical properties. I found out what I can get. However, the advantage of using the powdered phenolic paper newly provided in the present invention is that
Not only when drying at high temperatures over 100℃
It has also been found that the drying efficiency is improved as long as it is possible to dry at a higher temperature than when using conventional powdered phenolic resin and still prevent the deterioration of the properties of the laminate, even if the temperature is below. Even when dried at the same temperature as when using powdered phenolic resin, the reaction of the resin is further suppressed, so there is greater flexibility in processing conditions when molding with heat and pressure later, and molding can be performed in high temperature ranges in particular. It has the following advantages. The powdered phenolic resin described in the claims of the present invention is produced by mixing phenols and formaldehyde in the presence of ammonia and/or its derivatives at a temperature of 50 to 120°C, preferably 600 to 100°C. and has a low nitrogen content.
Gel time 120-300 seconds at 3.3-5.0 wt%, flow rate
It comprises a powdered phenolic resin characterized in that it is in the range of 150 to 230 mm. If the nitrogen content is less than 3.3% by weight, it will be difficult to obtain the desired resin properties and the thermosetting functionality of the resol will deteriorate if the reaction has proceeded to the extent that the resin does not form lumps during the papermaking process. Because the number of bases is too large, there is no thermal stability during the drying process, which causes a "fading" phenomenon during lamination processing. However, when the desired resin properties are achieved, it is difficult to form powder, and it is difficult to eliminate lumps during the papermaking process. Difficult to make and put into practical use. On the other hand, if the nitrogen content exceeds 5.0% by weight,
The resol has a small number of thermosetting functional groups and is excellent in thermal stability, but when laminated, the resulting laminate has poor electrical properties, water resistance, and mechanical properties, making it difficult to put it to practical use. If the gel time is less than 120 seconds or the fluidity is less than 150 mm, if the prepreg is obtained by drying at a high temperature in the drying process, a "fading" phenomenon will occur during lamination processing, whereas if drying is performed at a low temperature to avoid the "fading" phenomenon. In this case, the drying efficiency (productivity) of the prepreg is significantly reduced, which greatly impairs the economic efficiency in industrial production. In addition, the gel time is 300 seconds or the fluidity is 230 mm.
If it exceeds this value, the physical properties of the laminate obtained by lamination processing tend to deteriorate, which is not preferable. As the phenols used in the production of the powdered phenolic resin, phenols or derivatives thereof may be used alone or in any combination. Examples of phenol derivatives include alkyl phenols having an alkyl group having 1 to 6 carbon atoms, such as cresol, propyl phenol, isopropyl phenol, butyl phenol, and tert-butyl phenol, preferably meta-substituted phenols and bisphenol-A. , bisphenol S,
These are phenol dinuclear substances such as bisphenol F, and polyhydric phenols such as resorcinol. As the aldehyde source, formaldehyde, paraformaldehyde, acetaldehyde, glyoxal, etc. may be used alone or in combination, but formalin or paraformaldehyde is most preferably used. As the nitrogen source, ammonia and/or its derivatives such as hexamethylenetetramine, monoethylamine, triethylamine, etc. are used, but ammonia and hexamethylenetetramine are preferable. In addition to conventional resins such as solid ammonia resol resins, solid alkaline resol resins, and novolac resins, the powdered phenolic resin according to the present invention includes any additives commonly used in the past, such as silane coupling agents. , a mold release agent, a surfactant, etc., may be mixed and used within a range that does not impair the purpose of the present invention. Note that the heating and pressure molding of the prepreg in the production of the laminate of the present invention is generally carried out under conditions within the range of 120 to 180° C. and 50 to 200 kg/cm ² , although there are no particular limitations. Hereinafter, the product of the present invention will be explained using Examples, including the mode of use. Example 1 (a) Production of powdered phenolic resin 1000 g of phenol, 1290 g of 37% formalin,
250g of 28% ammonia water was reacted at 70°C for 3 hours. This was washed with 1000 g of warm water at 65°C, the supernatant liquid was removed, and the reaction product was poured into water, solidified by cooling, crushed in water, drained in a centrifuge, and air-dried to form a solid. A resol type resin was obtained. This was pulverized using a pulverizer to obtain a powdered resin. The properties of the resin obtained in this way include a gel time of 180 seconds,
The fluidity was 180 mm and the nitrogen content was 3.7%. (b) Production of paper loaded with phenolic resin and production of laminates 100 parts of LBKP beaten in 300 CSF and 120 parts of the above powdered resin are mixed in a chiest, and 0.4 parts of cationic polyacrylamide is added as a fixing agent.
% to fix the phenolic resin powder to the pulp. A wet sheet with a basis weight of 2.2 kg/m ² was made using a conventional paper making method using a cylinder paper machine and laminated using a making roll.
Dry for 80 minutes. Dry prepreg at 150℃
A good laminate with a thickness of 1.5 mm and no "fading" was obtained by heating and pressing for 60 minutes under molding conditions of 120 Kg/cm ² . Example 2 A wet sheet was prepared in the same manner as in Example 1(b) using the powdered phenolic resin obtained in Example 1(a). This laminated wet sheet is processed using a hot press machine with a Teflon coating.
After drying for 40 minutes at 110℃ and 0.2Kg/cm ² , heat and pressure was applied for 60 minutes at 150℃ and 120Kg/cm ² to produce a laminate with a thickness of 1.5mm and no "fading". I got it. Table 1 shows the properties of the laminate. Example 3 (a) Production of powdered phenolic resin 1000 g of phenol, 1290 g of 37% formalin,
After reacting 250 g of 28% ammonia water at 90°C for 1 hour, the reaction mixture was powdered in the same manner as in Example 1(a). The characteristics of this resin are gel time of 210 seconds, flow rate of 208 mm,
The nitrogen content was 3.7%. (b) Manufacture of paper loaded with phenol resin and manufacture of laminate A good laminate with a thickness of 1.5 mm without "fading" was obtained using the above powdered resin and in the same manner as in Example 1(b). Table 1 shows the properties of the laminate. Example 4 (a) Production of powdered phenolic resin 1000 g of phenol, 1290 parts of 37% formalin,
After reacting 320 g of 28% ammonia water at 70° C. for 4 hours, it is powdered in the same manner as in Example 1(a).
The characteristics of this resin are gel time of 300 seconds and flow rate of 225.
mm, and the nitrogen content was 4.5%. (b) Production of paper loaded with phenolic resin and production of laminates Using the above powdered phenolic resin, Example 1
In the same manner as in (b), a good laminate with a thickness of 1.5 mm and no "fading" was obtained. The properties of the laminate are shown in Table 1. Example 5 (a) Production of powdered phenolic resin 1000 g of phenol, 690 g of 37% formalin,
100 g of hexamethylenetetramine was reacted at 70° C. for 3 hours and then powdered in the same manner as in Example 1(a). The resin properties were a gel time of 140 seconds, a fluidity of 207 mm, and a nitrogen content of 3.5%. (b) Manufacture of paper loaded with phenol resin and manufacture of laminate. Using the above powdered resin, a good laminate with a thickness of 1.5 mm without "fading" was obtained in the same manner as in Example 1(b). Table 1 shows the properties of the laminate. Example 6 (a) Production of powdered phenolic resin 900 g of phenol, 100 g of metacresol, 37
% formalin 850g, 28% ammonia water 250g
After reacting at 70°C for 3 hours, the mixture is powdered in the same manner as in Example 1(a). The characteristics of this resin were a gel time of 130 seconds, a fluidity of 165 mm, and a nitrogen content of 3.7%. (b) Manufacture of paper loaded with phenol resin and manufacture of laminate. Using the above powdered resin, a good laminate with a thickness of 1.5 mm without "fading" was obtained in the same manner as in Example 1(b). Table 1 shows the properties of the laminate. Example 7 (a) Production of powdered phenolic resin 1000 g of phenol, 950 g of 37% formalin,
After reacting 180 g of 28% aqueous ammonia at 60° C. for 5 hours, it is powdered in the same manner as in Example 1(a). The properties of this resin were a gel time of 130 seconds, a fluidity of 164 mm, and a nitrogen content of 3.4%. (b) Production of paper loaded with phenolic resin and production of laminates Using the above powdered phenolic resin, Example 1
In the same manner as in (b), a good laminate with a thickness of 1.5 mm and no "fading" was obtained. Table of properties of laminates
Shown in 1. Example 8 (a) Production of powdered phenolic resin 1000 g of phenol, 1290 g of 37% formalin,
After reacting 320 g of 28% ammonia water at 90° C. for 1 hour, the reaction mixture was powdered in the same manner as in Example 1(a). The characteristics of this resin are gel time of 260 seconds, flow rate of 223 mm,
The nitrogen content was 4.5%. (b) Manufacture of paper loaded with phenol resin and manufacture of laminate A laminate with a thickness of 1.5 mm without "fading" was obtained using the above powdered resin and in the same manner as in Example 1(b). Table 1 shows the properties of the laminate. Comparative Example 1 (a) Production of powdered phenolic resin 1000 g of phenol, 2160 g of 37% formalin,
After reacting 70 g of 28% ammonia water at 70°C for 3 hours, it was made into powder in the same manner as in Example 1(a).The resin properties were a gel time of 50 seconds, a fluidity of 48 mm, and a nitrogen content of 1.4%. . (b) Manufacture of paper loaded with phenolic resin and manufacture of laminates Using the above powdered resin, a laminate with a thickness of 1.5 mm was obtained in the same manner as in Example 1(b), but "fading" occurred.
Table 1 shows the properties of the laminate that produced this. On the other hand, even if a powdered resin having the above composition is used, if the drying temperature is set low, the progress of the reaction of the resin can be suppressed, so that a good laminate can be obtained. Table 2 compares the state of the laminates when dried at 120°C and 80°C. 80℃
Drying in a vacuum cleaner is good without causing any "fading", but it takes a long time to dry, which greatly impairs economic efficiency in industrial production, which is contrary to the purpose of the present invention. Comparative Example 2 (a) Production of phenolic resin 1000 g of phenol, 2160 g of 37% formalin,
After reacting 70 g of 28% ammonia water at 70°C for 1.5 hours, the resin properties obtained in the same manner as in Example 1(a) were: gel time 145 seconds, fluidity 160 mm, and nitrogen content.
It was 1.4%, but it became lumpy at room temperature,
It did not turn into powder. Therefore, the above-mentioned resin could not be used for producing paper loaded with phenolic resin. Comparative Example 3 (a) Production of powdered phenolic resin 1000 g of phenol, 1380 parts of 37%, and 360 g of 28% ammonia water were reacted at 70°C for 3 hours, and then powdered in the same manner as in Example 1(a). This resin had a gel time of 340 seconds, a fluidity of 270 mm, and a nitrogen content of 5.3%. (b) Manufacture of paper loaded with phenolic resin and manufacture of laminate A laminate with a thickness of 1.5 mm was obtained using the above powdered resin in the same manner as in Example 1(b), but the electrical properties were poor. It was hot. Table 1 shows the characteristics of the laminate.
Shown below.

【表】【table】

Claims

【特許請求の範囲】１水性媒体中に繊維基材と、窒素含有量が3.3
〜5.0重量％であり、且つJIS−Ｋ−6910による
150℃でのゲルタイムが120〜300秒、JIS−Ｋ−
6910による125℃での流動度が150〜230mmである
粉状アンモニアレゾール樹脂単独又は該樹脂を主
体とする粉状フエノール樹脂を混合分散させて得
られる分散液を用いて湿式抄造法により樹脂内添
ウエツトシートを作製し、得られる該ウエツトシ
ートを加熱乾燥してプリプレグを調製し、次いで
このプリプレグの１枚又は複数枚を加熱加圧成型
して積層板を得ることを特徴とする積層板の製造
方法。２前記分散液が定着剤その他の添加剤を含む特
許請求の範囲第１項記載の方法。[Claims] 1. A fiber base material in an aqueous medium and a nitrogen content of 3.3.
~5.0% by weight, and according to JIS-K-6910
Gel time at 150℃ is 120-300 seconds, JIS-K-
6910 with a fluidity of 150 to 230 mm at 125°C, or a dispersion obtained by mixing and dispersing a powdered ammonia aresol resin based on this resin or a powdered phenol resin mainly composed of this resin. A method for manufacturing a laminate, which comprises producing a wet sheet, heating and drying the resulting wet sheet to prepare a prepreg, and then molding one or more of the prepregs under heat and pressure to obtain a laminate. 2. The method according to claim 1, wherein the dispersion liquid contains a fixing agent and other additives.