JPH04257398A - Heat-resistant high-shrinkage paper - Google Patents
Heat-resistant high-shrinkage paperInfo
- Publication number
- JPH04257398A JPH04257398A JP3505491A JP3505491A JPH04257398A JP H04257398 A JPH04257398 A JP H04257398A JP 3505491 A JP3505491 A JP 3505491A JP 3505491 A JP3505491 A JP 3505491A JP H04257398 A JPH04257398 A JP H04257398A
- Authority
- JP
- Japan
- Prior art keywords
- heat
- paper
- resistant
- shrinkage
- aromatic polyamide
- 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.)
- Pending
Links
- 239000000835 fiber Substances 0.000 claims abstract description 33
- 239000004760 aramid Substances 0.000 claims abstract description 15
- 229920003235 aromatic polyamide Polymers 0.000 claims abstract description 15
- 238000002441 X-ray diffraction Methods 0.000 claims abstract description 5
- 239000004020 conductor Substances 0.000 abstract description 5
- 238000010292 electrical insulation Methods 0.000 abstract description 5
- 239000012210 heat-resistant fiber Substances 0.000 abstract 2
- 230000010485 coping Effects 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 description 8
- -1 poly(m-phenylene isophthalamide) Polymers 0.000 description 7
- 239000004952 Polyamide Substances 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 229920002647 polyamide Polymers 0.000 description 5
- 238000003490 calendering Methods 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 239000002966 varnish Substances 0.000 description 4
- 125000003118 aryl group Chemical group 0.000 description 3
- 230000008602 contraction Effects 0.000 description 3
- 239000002002 slurry Substances 0.000 description 3
- 238000004804 winding Methods 0.000 description 3
- 239000004696 Poly ether ether ketone Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229920000889 poly(m-phenylene isophthalamide) Polymers 0.000 description 2
- 229920002530 polyetherether ketone Polymers 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- KXDHJXZQYSOELW-UHFFFAOYSA-N Carbamic acid Chemical compound NC(O)=O KXDHJXZQYSOELW-UHFFFAOYSA-N 0.000 description 1
- OFOBLEOULBTSOW-UHFFFAOYSA-N Malonic acid Chemical compound OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 238000010622 cold drawing Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 150000004985 diamines Chemical class 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000009998 heat setting Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000002074 melt spinning Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 239000013055 pulp slurry Substances 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000002166 wet spinning Methods 0.000 description 1
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は電気絶縁用途に使用する
耐熱高収縮紙に関するものである。更に詳しくは高収縮
性を利用して製造工程の合理化と信頼性の向上に有用な
耐熱高収縮紙を提供するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to heat-resistant high shrinkage paper used for electrical insulation purposes. More specifically, the present invention provides a heat-resistant, high-shrinkage paper that utilizes its high shrinkage properties and is useful for streamlining manufacturing processes and improving reliability.
【０００２】0002
【従来の技術】Ｈ種グレ−ドの耐熱性のある電気絶縁紙
としては従来、芳香族ポリアミド紙が使用されている。
また電気絶縁用途では例えばモ−ルドトランスのように
樹脂含浸や或いは巻線用のようにワニス含浸されて使用
する場合が多い。BACKGROUND OF THE INVENTION Conventionally, aromatic polyamide paper has been used as heat-resistant electrically insulating paper of class H grade. Further, in electrical insulation applications, for example, it is often used impregnated with resin, as in mold transformers, or impregnated with varnish, as in winding wires.
【０００３】電気絶縁紙を巻線に巻く場合は通常オ−バ
−ラップして多層に巻く場合が多い。この場合、層と層
との間に空気層を含まない様に製造工程では細心の注意
が必要である。また樹脂やワニスを含浸させる場合、真
空含浸法を利用して層と層との間あるいは導体と絶縁紙
との間に空気が取り込まれ無いように工夫しているが、
実際の製造工程では細心の注意が必要である。電気絶縁
紙間や電気絶縁紙と導体との間に空気が含まれると高電
圧がかかった場合、コロナ放電が発生し、ついには絶縁
破壊の原因となるので製造工程では重要な管理項目とな
っている。このため人手をかけて作業を入念に実施した
り、工数をかけて検査をしているため、それが製造コス
トの上昇につながり、また製品の信頼性を落とすといっ
た問題点があった。[0003] When electrically insulating paper is wound into a winding wire, it is usually wound in multiple layers in an overlapping manner. In this case, great care must be taken in the manufacturing process to avoid air spaces between the layers. Also, when impregnating resin or varnish, vacuum impregnation is used to prevent air from being trapped between layers or between the conductor and insulating paper.
Great care must be taken in the actual manufacturing process. If air is trapped between the electrically insulating paper or between the electrically insulating paper and the conductor, corona discharge will occur when high voltage is applied, and this will eventually cause insulation breakdown, so this is an important control item in the manufacturing process. ing. For this reason, the work has to be carried out carefully and the inspections have to take many man-hours, which leads to an increase in manufacturing costs and reduces the reliability of the product.
【０００４】0004
【発明の目的】本発明の目的は、樹脂やワニスが含浸さ
れる電気絶縁紙において、電気絶縁紙間や電気絶縁紙と
導体との間に空気がとりこまれて電気絶縁の信頼性が低
下する問題やこのため人手をかけて製造コストが上昇す
るといった問題を解決することにある。[Object of the Invention] The purpose of the present invention is to prevent the reliability of electrical insulation from decreasing in electrically insulating paper impregnated with resin or varnish because air is trapped between the electrically insulating papers or between the electrically insulating paper and the conductor. The aim is to solve problems such as increased manufacturing costs due to manual labor.
【０００５】[0005]
【発明の構成】本発明は「芳香族ポリアミドパルプ８０
〜２０重量％および耐熱性短繊維２０〜８０重量％から
なる合成紙において、芳香族ポリアミドパルプおよびＸ
線パタ−ンからみて結晶化していなく、Ｓ３００（３０
０度Ｃにおける乾熱収縮率）が６９％以上である耐熱性
短繊維を湿式で抄造してなり、２５０度Ｃにおける熱収
縮率が７％以上であることを特徴とする耐熱高収縮紙」
である。Structure of the Invention The present invention is based on ``aromatic polyamide pulp 80''.
-20% by weight of aromatic polyamide pulp and 20-80% by weight of heat-resistant short fibers,
Judging from the line pattern, it is not crystallized and is S300 (30
"Heat-resistant high shrinkage paper produced by wet-forming heat-resistant short fibers having a dry heat shrinkage rate of 69% or more at 0 degrees C, and having a heat shrinkage rate of 7% or more at 250 degrees C."
It is.
【０００６】耐熱性短繊維としては芳香族ポリアミド繊
維やポリエ−テルエ−テルケトン繊維等が挙げられる。[0006] Examples of heat-resistant short fibers include aromatic polyamide fibers and polyetheretherketone fibers.
【０００７】芳香族ポリアミドパルプの混率が８０％を
越える場合は合成紙の２５０度Ｃにおける熱収縮率を７
％以上とすることが困難になる。When the blending ratio of aromatic polyamide pulp exceeds 80%, the heat shrinkage rate of the synthetic paper at 250 degrees C.
% or more becomes difficult.
【０００８】一方、芳香族ポリアミドパルプの混率が２
０％未満の場合は得られる合成紙の強度が小となり実用
性が乏しい。On the other hand, when the blending ratio of aromatic polyamide pulp is 2
If it is less than 0%, the strength of the resulting synthetic paper will be low and it will be of poor practical use.
【０００９】また、Ｘ線パタ−ンからみて結晶化してい
る耐熱性短繊維を用いると高収縮率を得ることができな
い。[0009] Furthermore, if heat-resistant staple fibers that are crystallized as seen from the X-ray pattern are used, a high shrinkage rate cannot be obtained.
【００１０】Ｓ３００（３００度Ｃにおける乾熱収縮率
）が６９％未満である耐熱性短繊維を用いた場合も同様
である。The same applies when heat-resistant short fibers having S300 (dry heat shrinkage rate at 300° C.) of less than 69% are used.
【００１１】使用する芳香族ポリアミドとしては従来公
知の
（ａ） 芳香族環を有するジカルボン酸と芳香族環を
有するジアミンとの縮合ポリアミド
（ｂ） 芳香族環を有するアミノカルボン酸を縮合し
てなる縮合ポリアミド
（ｃ） 前記（ａ），（ｂ）を共重合した縮合ポリア
ミドがあげられる。The aromatic polyamide used is a conventionally known (a) condensed polyamide of a dicarboxylic acid having an aromatic ring and a diamine having an aromatic ring (b) a condensed polyamide formed by condensing an aminocarboxylic acid having an aromatic ring. Condensed polyamide (c) A condensed polyamide obtained by copolymerizing the above (a) and (b) can be mentioned.
【００１２】芳香族ポリアミドパルプは公知の例えば特
公昭３５−１１８５１号公報、特公昭３７−５７３２号
公報に記載されているものである。特にポリ（ｍ−フエ
ニレンイソフタルアミド）が好ましい。[0012] The aromatic polyamide pulp is known, for example, as described in Japanese Patent Publications No. 35-11851 and Japanese Patent Publication No. 37-5732. Particularly preferred is poly(m-phenylene isophthalamide).
【００１３】耐熱性短繊維としての芳香族ポリアミド短
繊維もポリ（ｍ−フエニレンイソフタルアミド）短繊維
が好ましい。短繊維の形態としては単糸繊度２０デニ−
ル以下、繊維長３〜２０ｍｍの範囲のものが好ましい。The aromatic polyamide short fibers used as the heat-resistant short fibers are preferably poly(m-phenylene isophthalamide) short fibers. The short fiber has a single yarn fineness of 20 denier.
Preferably, the fiber length is 3 to 20 mm.
【００１４】Ｘ線パタ−ンからみて結晶化していなく、
Ｓ３００（３００度Ｃにおける乾熱収縮率）が６９％以
上である耐熱性短繊維としては、例えば延伸倍率が２．
５倍以上で実質的に熱セットされていない配向未結晶化
短繊維が好ましい。延伸倍率が２．５倍未満でのもの、
あるいは熱セットされて結晶化させたものでは高収縮紙
を得ることは難しい。他の耐熱性短繊維としてポリエ−
テルエ−テルケトン繊維の場合でも同様であり、延伸倍
率が２．５倍以上で実質的に熱セットされていない配向
未結晶化短繊維が好ましい。[0014] Judging from the X-ray pattern, it is not crystallized,
Heat-resistant staple fibers having an S300 (dry heat shrinkage rate at 300 degrees Celsius) of 69% or more include, for example, fibers with a draw ratio of 2.
Oriented uncrystallized short fibers that are not substantially heat set at 5 times or more are preferred. Those with a stretching ratio of less than 2.5 times,
Alternatively, it is difficult to obtain high shrinkage paper using heat-set crystallized paper. Polyester as another heat-resistant staple fiber
The same holds true for the teletherketone fibers, and oriented uncrystallized short fibers with a draw ratio of 2.5 times or more and which are not substantially heat set are preferred.
【００１５】本発明の耐熱高収縮紙は芳香族ポリアミド
パルプおよびＸ線パタ−ンからみて結晶化していなく、
Ｓ３００（３００度Ｃにおける乾熱収縮率）が６９％以
上である耐熱性短繊維を湿式で抄造してなり、２５０度
Ｃにおける熱収縮率が７％以上となるものである。２５
０度Ｃにおける熱収縮率を７％以上とするには耐熱性短
繊維の延伸条件あるいは湿式抄造後のカレンダ−加工条
件を調整する。湿式抄造の方法は従来公知の方法を用い
る。The heat-resistant high shrinkage paper of the present invention is made of aromatic polyamide pulp and has no crystallization as seen from the X-ray pattern.
It is made by wet-forming heat-resistant staple fibers having an S300 (dry heat shrinkage rate at 300 degrees Celsius) of 69% or more, and has a heat shrinkage rate at 250 degrees Celsius of 7% or more. 25
In order to make the heat shrinkage rate at 0° C. 7% or more, the stretching conditions of the heat-resistant short fibers or the calendering conditions after wet papermaking are adjusted. A conventionally known method is used for wet papermaking.
【００１６】[0016]
【発明の効果】本発明によって得られる耐熱高収縮紙は
以下の効果を有する。すなわち樹脂やワニスが含浸され
る電気絶縁紙として巻線を製造する際、工程中に受ける
熱処理により発生する紙の収縮力により、電気絶縁紙間
や電気絶縁紙と導体との間にとりこまれた空気が系外に
排除されるので製造工程が簡略化されるとともに製品の
信頼性が向上する。Effects of the Invention The heat-resistant high shrinkage paper obtained by the present invention has the following effects. In other words, when winding wires are manufactured using electrically insulating paper impregnated with resin or varnish, the shrinkage force of the paper generated by the heat treatment during the process causes particles to be trapped between the electrically insulating papers or between the electrically insulating paper and the conductor. Since air is removed from the system, the manufacturing process is simplified and product reliability is improved.
【００１７】[0017]
【実施例】以下、実施例により本発明の耐熱高収縮紙の
製造方法を示す。実施例における下記特性の評価は以下
の方法で行った。
（１）坪量：ＪＩＳ−Ｐ８１２４に準じて測定した。
（２）厚さ：ＪＩＳ−Ｃ２１１１の７により測定した。
（３）密度：ＪＩＳ−Ｃ２１１１の６．１により測定し
た。
（４）引張強さと伸び：定速伸長型引張試験機を用い、
ＪＩＳ−Ｃ２１１１の７により測定した。
（５）絶縁破壊強さ（ＢＤＶ）：ＪＩＳ−Ｃ２１１１９
１８．１により測定した。
（６）熱収縮率：２５０度Ｃの熱風乾燥機にフリ−状態
で６０分間放置し、収縮前後の値から下記式により算出
した。
（収縮前長さ−収縮後長さ）／収縮前長さ×１００％（
７）Ｓ３００：繊維束３０００デニ−ル、サンプル長３
０ｃｍになるようにサンプリングし上端を固定して下端
に１００ｇの荷重をかけ垂直に垂らしたときの長さをＬ
０ とする。次にそれを３００±２度Ｃの熱風乾燥機に
１５分間放置し、その後のサンプル長をＬ１ とする。
この試験を３回繰り返し、次式によりＳ３００を算出し
平均値で表した。
Ｓ３００＝（Ｌ０ −Ｌ１ ）／Ｌ０ ×１００[Example] The method for producing the heat-resistant high shrinkage paper of the present invention will be described below with reference to Examples. Evaluation of the following characteristics in Examples was performed by the following method. (1) Basis weight: Measured according to JIS-P8124. (2) Thickness: Measured according to JIS-C2111-7. (3) Density: Measured according to 6.1 of JIS-C2111. (4) Tensile strength and elongation: Using a constant speed extension type tensile tester,
Measured according to JIS-C2111-7. (5) Dielectric breakdown strength (BDV): JIS-C21119
Measured according to 18.1. (6) Heat shrinkage rate: The product was left in a hot air dryer at 250 degrees Celsius for 60 minutes, and calculated from the values before and after shrinkage using the following formula. (Length before contraction - Length after contraction) / Length before contraction x 100% (
7) S300: Fiber bundle 3000 denier, sample length 3
Sample the sample so that it is 0cm, fix the top end, apply a load of 100g to the bottom end, and hang it vertically.The length is L.
Set to 0. Next, it is left in a hot air dryer at 300±2 degrees Celsius for 15 minutes, and the sample length thereafter is defined as L1. This test was repeated three times, and S300 was calculated using the following formula and expressed as an average value. S300=(L0-L1)/L0×100
【００
１８】00
18]
【実施例１〜５，比較例１〜６】ポリメタフエニレンイ
ソフタルアミドから公知の溶液剪断法によりパルプを作
成し、このパルプをパルパ−、高速離解機、デイスクリ
フアイナ−を使用してスラリ−濃度０．３％でカナデイ
アン標準濾水度１１０ｍｌの水性スラリ−を作成した。[Examples 1 to 5, Comparative Examples 1 to 6] Pulp was prepared from polymetaphenylene isophthalamide by a known solution shearing method, and this pulp was slurried using a pulper, a high-speed disintegrator, and a disc clarifier. - An aqueous slurry with a concentration of 0.3% and Canadian standard freeness of 110 ml was prepared.
【００１９】一方、ポリメタフエニレンイソフタルアミ
ド短繊維として、湿式紡糸で得られた未延伸糸を冷延伸
法または沸水中で種種の延伸倍率で延伸し、熱セットは
行わずに単糸繊度３デニ−ル、繊維長６．０ｍｍの短繊
維を得た。ついで前記パルプスラリ−とポリメタフエニ
レンイソフタルアミド短繊維とを表１に示した混率で混
合し、均一抄紙スラリ−を作成した。On the other hand, as polymetaphenylene isophthalamide staple fibers, undrawn yarns obtained by wet spinning are stretched at various draw ratios using a cold drawing method or in boiling water to obtain a single yarn fineness of 3 without heat setting. Short fibers with a denier and a fiber length of 6.0 mm were obtained. Next, the pulp slurry and polymetaphenylene isophthalamide short fibers were mixed at the mixing ratio shown in Table 1 to prepare a uniform papermaking slurry.
【００２０】次ぎにタッピ−式角型手抄機を用いて該抄
紙スラリ−を抄紙したのち乾燥し、約４０ｇ／ｍ２ の
乾燥紙を得た。得られた乾燥紙をそのまま評価したもの
と更に常温でスチ−ルロ−ルとスチ−ルロ−ルとのニッ
プロ−ルからなるカレンダ−で線圧３００ｋｇ／ｃｍで
カレンダ−加工を実施した。結果を表１に示す。[0020] Next, the paper slurry was made into paper using a Tappy type square hand paper machine, and then dried to obtain dry paper with a weight of about 40 g/m2. The obtained dried paper was evaluated as it was and was further calendered at room temperature using a calender consisting of a steel roll and a nip roll of a steel roll at a linear pressure of 300 kg/cm. The results are shown in Table 1.
【００２１】他の実施例として、溶融紡糸して得られた
ポリエ−テルエ−テルケトン繊維を３．０倍に延伸し、
未熱セットで２．５デニ−ル、６．０ｍｍ長の短繊維と
した。この短繊維から上記と同様の方法でカレンダ−加
工紙を得た。As another example, polyetheretherketone fibers obtained by melt spinning were stretched 3.0 times,
It was set unheated to produce short fibers of 2.5 denier and 6.0 mm long. Calendered paper was obtained from the short fibers in the same manner as above.
【００２２】比較例として、芳香族ポリアミドパルプの
混率が高い場合と低い場合および市販の芳香族ポリアミ
ド紙の抄上紙とカレンダ−加工紙の例を表１に示した。As comparative examples, Table 1 shows cases in which the blending ratio of aromatic polyamide pulp was high and low, as well as examples of paper made from commercially available aromatic polyamide paper and calendered paper.
【表１】[Table 1]
Claims (2)
および耐熱性短繊維２０〜８０重量％からなる合成紙に
おいて、芳香族ポリアミドパルプおよびＸ線パタ−ンか
らみて結晶化していなく、Ｓ３００（３００度Ｃにおけ
る乾熱収縮率）が６９％以上である耐熱性短繊維を湿式
で抄造してなり、２５０度Ｃにおける熱収縮率が７％以
上であることを特徴とする耐熱高収縮紙。。Claim 1: Aromatic polyamide pulp 80-20% by weight
and synthetic paper consisting of 20 to 80% by weight of heat-resistant short fibers, which is not crystallized when viewed from the aromatic polyamide pulp and X-ray pattern, and has an S300 (dry heat shrinkage rate at 300 degrees Celsius) of 69% or more. A heat-resistant high shrinkage paper made by wet-forming heat-resistant short fibers and having a heat shrinkage rate of 7% or more at 250 degrees C. .
る請求項１に記載の耐熱高収縮紙。2. The heat-resistant high shrinkage paper according to claim 1, wherein the heat-resistant short fibers are aromatic polyamide fibers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3505491A JPH04257398A (en) | 1991-02-06 | 1991-02-06 | Heat-resistant high-shrinkage paper |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3505491A JPH04257398A (en) | 1991-02-06 | 1991-02-06 | Heat-resistant high-shrinkage paper |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04257398A true JPH04257398A (en) | 1992-09-11 |
Family
ID=12431325
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3505491A Pending JPH04257398A (en) | 1991-02-06 | 1991-02-06 | Heat-resistant high-shrinkage paper |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04257398A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998056987A1 (en) * | 1997-06-10 | 1998-12-17 | Teijin Limited | Heat-resistant fiber paper |
-
1991
- 1991-02-06 JP JP3505491A patent/JPH04257398A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998056987A1 (en) * | 1997-06-10 | 1998-12-17 | Teijin Limited | Heat-resistant fiber paper |
| US6319605B1 (en) * | 1997-06-10 | 2001-11-20 | Teijin Limited | Heat-resistant fiber paper |
| CN1098392C (en) * | 1997-06-10 | 2003-01-08 | 帝人株式会社 | Heat resistant fiber paper |
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