JPS6111419B2 - - Google Patents
Info
- Publication number
- JPS6111419B2 JPS6111419B2 JP8248679A JP8248679A JPS6111419B2 JP S6111419 B2 JPS6111419 B2 JP S6111419B2 JP 8248679 A JP8248679 A JP 8248679A JP 8248679 A JP8248679 A JP 8248679A JP S6111419 B2 JPS6111419 B2 JP S6111419B2
- Authority
- JP
- Japan
- Prior art keywords
- sheet
- polyolefin resin
- cellulose
- insulating paper
- insulator
- 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
Links
- 229920005672 polyolefin resin Polymers 0.000 claims description 38
- 229920002678 cellulose Polymers 0.000 claims description 23
- 239000001913 cellulose Substances 0.000 claims description 23
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 claims description 19
- 229910000077 silane Inorganic materials 0.000 claims description 19
- 239000012212 insulator Substances 0.000 claims description 15
- 150000002430 hydrocarbons Chemical class 0.000 claims description 13
- 239000004215 Carbon black (E152) Substances 0.000 claims description 9
- 229930195733 hydrocarbon Natural products 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 4
- 238000010030 laminating Methods 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 239000003921 oil Substances 0.000 description 19
- 238000000034 method Methods 0.000 description 11
- 239000000853 adhesive Substances 0.000 description 8
- 230000001070 adhesive effect Effects 0.000 description 8
- 238000001125 extrusion Methods 0.000 description 5
- 238000000576 coating method Methods 0.000 description 4
- 150000004996 alkyl benzenes Chemical class 0.000 description 3
- 238000003475 lamination Methods 0.000 description 3
- 238000010521 absorption reaction Methods 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- 230000008961 swelling Effects 0.000 description 2
- WSSSPWUEQFSQQG-UHFFFAOYSA-N 4-methyl-1-pentene Chemical compound CC(C)CC=C WSSSPWUEQFSQQG-UHFFFAOYSA-N 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 125000000956 methoxy group Chemical group [H]C([H])([H])O* 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 235000010446 mineral oil Nutrition 0.000 description 1
- 239000002985 plastic film Substances 0.000 description 1
- 229920006255 plastic film Polymers 0.000 description 1
- 229920001083 polybutene Polymers 0.000 description 1
- 229920001748 polybutylene Polymers 0.000 description 1
- -1 polypropylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 238000007348 radical reaction Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
Landscapes
- Insulating Bodies (AREA)
- Laminated Bodies (AREA)
Description
本発明は、OFケーブル、油入りトランス等に
使用するのに好適なシート状絶縁体の製造方法に
関する。
周知の如く、OFケーブル、油入りトランス等
の絶縁材料としてセルロース系絶縁紙が使用され
ているが、このセルロース系絶縁紙のみでは近年
の使用電圧の高電圧化に対応することはできな
い。そこでこのような高電圧化に対応でき、優秀
な誘電特性や耐電圧特性を有する絶縁体の出現が
強く要望されており、この要望を満たすのとして
炭化水素系絶縁油を混和したポリオレフイン樹脂
シートとセルロース系絶縁紙とを貼り合わせたシ
ート状絶縁体が提案されている。しかしながら、
ポリオレフイン樹脂は極性基を有していないた
め、セルロースのような極性基を有する化合物と
は接着しにくく、単に紙表面の繊維と機械的に絡
まることによつて貼り合わされているにすぎな
い。従つて、ポリオレフイン樹脂シートとセルロ
ース系絶縁紙との接着力は低く、剥離等の不都合
が生じていた。また、絶縁油がポリオレフイン樹
脂シートとセルロース系絶縁紙との間に介在して
しまうため、ポリオレフイン樹脂シートとセルロ
ース系絶縁紙との接着力が更に低下し、剥離等の
不都合が度々生じていた。
本発明者等は上記従来のシート状絶縁体に付随
していた欠点を解消するために鋭意研究を行つた
結果、炭化水素系絶縁油を混和したポリオレフイ
ン樹脂シートが軟化或いは溶融状態にあるときに
RSiX3（Ｒは−NH−、
The present invention relates to a method for producing a sheet-like insulator suitable for use in OF cables, oil-filled transformers, and the like. As is well known, cellulose-based insulating paper is used as an insulating material for OF cables, oil-filled transformers, etc., but this cellulose-based insulating paper alone cannot cope with the high voltages used in recent years. Therefore, there is a strong demand for an insulator that can handle such high voltages and has excellent dielectric properties and withstand voltage properties.To meet this demand, polyolefin resin sheets mixed with hydrocarbon-based insulating oil and A sheet-like insulator bonded with cellulose-based insulating paper has been proposed. however,
Since polyolefin resin does not have a polar group, it is difficult to adhere to a compound having a polar group such as cellulose, and is simply bonded by mechanically entangling the fibers on the paper surface. Therefore, the adhesive strength between the polyolefin resin sheet and the cellulose insulating paper is low, resulting in problems such as peeling. Further, since the insulating oil is interposed between the polyolefin resin sheet and the cellulose-based insulating paper, the adhesive strength between the polyolefin resin sheet and the cellulose-based insulating paper is further reduced, and problems such as peeling often occur. The inventors of the present invention conducted intensive research to eliminate the drawbacks associated with the conventional sheet-shaped insulators mentioned above, and found that when a polyolefin resin sheet mixed with a hydrocarbon insulating oil is in a softened or molten state.
RSiX 3 (R is -NH-,
【式】−SH基を１個以
上含む炭化水素基、Ｘは−OH、−OCH3、−
OC2H5、−OCOCH3等の基）の化学式で表わされ
る有機シランを塗布した後、セルロース系絶縁紙
とラミネートすると、ポリオレフイン樹脂シート
とセルロース系絶縁紙とが良好かつ確実に接着さ
れることを知見した。本発明はこれらの知見に基
づいて完成された。その特徴は、ポリオレフイン
樹脂シート或いはポリオレフイン樹脂100重量部
当り５〜30重量部の炭化水素系絶縁油を混合した
混和物シートが軟化或いは溶融状態にあるときに
RSiX3（Ｒは−NH−、[Formula] Hydrocarbon group containing one or more -SH groups, X is -OH, -OCH 3 , -
When an organic silane represented by the chemical formula (such as OC 2 H 5 , -OCOCH 3 , etc.) is applied and then laminated with cellulose insulating paper, the polyolefin resin sheet and cellulose insulating paper are bonded well and reliably. I found out. The present invention was completed based on these findings. The feature is that when a polyolefin resin sheet or a mixture sheet containing 5 to 30 parts by weight of hydrocarbon insulating oil per 100 parts by weight of polyolefin resin is in a softened or molten state,
RSiX 3 (R is -NH-,
【式】−SH基を１個
以上含む炭化水素基、Ｘは−OH、−OCH3、−
OC2H5、−OCOCH3等の基）の化学式で表わされ
る有機シランを塗布した後、セルロース系絶縁紙
とラミネートすることにある。
以下、本発明を詳細に説明する。
まず、ポリオレフイン樹脂に炭化水素系絶縁油
を混練混合して混和物シートとする。炭化水素系
絶縁油の混合によりポリオレフイン樹脂の吸油膨
潤を抑制することができる。この絶縁油が混和さ
れたポリオレフイン樹脂シートが軟化或いは溶融
状態にあるときにRSiX3（Ｒは−NH−、
[Formula] Hydrocarbon group containing one or more -SH groups, X is -OH, -OCH 3 , -
After applying an organic silane represented by the chemical formula (groups such as OC 2 H 5 , -OCOCH 3, etc.), it is laminated with cellulose-based insulating paper. The present invention will be explained in detail below. First, a polyolefin resin is kneaded and mixed with a hydrocarbon insulating oil to form a mixture sheet. By mixing the hydrocarbon insulating oil, oil absorption and swelling of the polyolefin resin can be suppressed. When the polyolefin resin sheet mixed with this insulating oil is in a softened or molten state, RSiX 3 (R is -NH-,
【式】−SH基を１個以上含む炭化水素基、
Ｘは−OH、−OCH3−OC2H5、−OCOCH3等の
基）の化学式で表わされる有機シランを噴霧法、
はけ塗り法等の適宜の方法で塗布した後、有機シ
ランの塗布されたポリオレフイン樹脂シートをセ
ルロース系絶縁紙とラミネートさせる。
そして、有機シランを塗布する時期は、ポリオ
レフイン樹脂が押出ラミネート法等の適宜の方法
で押出されて軟化或いは溶融状態にある時でも良
く、或いはポリオレフイン樹脂をシートとした後
加熱して前記の場合と同様に軟化或いは溶融状態
にある時でも良い。また、ポリオレフイン樹脂を
シートとした後、有機シランを塗布し、加熱しな
がらセルロース系絶縁紙とラミネートする方法で
も良い。上記各種の有機シランの塗布法のうち溶
融状態のポリオレフイン樹脂シートに有機シラン
を塗布する方法を使用するのが好ましい。なお、
有機シランの塗布はポリオレフイン樹脂シートの
両面でも良いが、セルロース系絶縁紙との接合面
だけで充分である。
ところで、ポリオレフイン樹脂としては、ポリ
プロピレン、ポリブテン−１、ポリ４−メチルペ
ンテン−１等が使用できる。また、上記シランは
ＲがNH2（CH2）3−、HS（CH2）3−、である化合
物が特に好ましいものである。シランの使用量は
ポリオレフイン樹脂層の表面積１m2当たり１ｇ以
下で充分である。好適な量は500〜2000ｍｇ／m2
である。余りに少ないと充分な接着力が得られ
ず、一方余りに多くても何の利点も得られない。
さらに、炭化水素系絶縁油としては、ポリブテ
ン、アルキルベンゼン、鉱油系絶縁油等を使用で
きる。その使用量はポリオレフイン樹脂100重量
部当たり５〜30重量部であり、５重量部未満であ
るとポリオレフイン樹脂の吸油膨潤を充分に抑制
できないことがあり、一方30重量部より多いと配
合した絶縁油がシート表面に分離することがあ
る。そして、押出温度を260〜320℃程度とするこ
とが好ましい。なお、前記の有機シランの塗布工
程とラミネート工程とにより、第１図に示すよう
にポリオレフイン樹脂シート２の両面に絶縁紙
３，３を設けたシート状絶縁体１を形成すること
ができ、また第２図に示すようにポリオレフイン
樹脂シート２の片面に絶縁紙３を設けると共に他
面にプラスチツクフイルム４を設けたシート状絶
縁紙１を形成することもできる。
ところで、本発明の方法で形成されたシート状
絶縁体における炭化水素系絶縁油を混和したポリ
オレフイン樹脂シートとセルロース系絶縁紙とは
確実に貼り合させれ、それらの接着力は高いが、
その理由は次のようであると考えられる。軟化或
いは溶融状態のポリオレフイン樹脂はわずかでは
あるが熱分解されてラジカルが発生している。そ
して、このラジカル化したポリオレフイン樹脂
と、塗布された有機シランの分子内に存在する−
NH−、[Formula] A hydrocarbon group containing one or more -SH groups, X is a group such as -OH, -OCH 3 -OC 2 H 5 , -OCOCH 3, etc.) by spraying an organic silane,
After coating by a suitable method such as brush coating, the polyolefin resin sheet coated with organic silane is laminated with cellulose-based insulating paper. The organic silane may be applied when the polyolefin resin is extruded by an appropriate method such as an extrusion lamination method and is in a softened or molten state, or when the polyolefin resin is formed into a sheet and then heated. Similarly, it may be in a softened or molten state. Alternatively, a method may be used in which a polyolefin resin is formed into a sheet, then organic silane is applied, and the sheet is laminated with cellulose-based insulating paper while heating. Among the various organic silane coating methods described above, it is preferable to use a method in which the organic silane is coated on a molten polyolefin resin sheet. In addition,
The organic silane may be applied to both sides of the polyolefin resin sheet, but it is sufficient to apply the organic silane only to the surface bonded to the cellulose insulating paper. By the way, polypropylene, polybutene-1, poly-4-methylpentene-1, etc. can be used as the polyolefin resin. Moreover, the above-mentioned silane is particularly preferably a compound in which R is NH 2 (CH 2 ) 3 − or HS(CH 2 ) 3 −. It is sufficient that the amount of silane used is 1 g or less per 1 m 2 of surface area of the polyolefin resin layer. The preferred amount is 500-2000mg/ m2
It is. If it is too small, sufficient adhesion cannot be obtained, while if it is too large, no advantage will be obtained.
Further, as the hydrocarbon-based insulating oil, polybutene, alkylbenzene, mineral oil-based insulating oil, etc. can be used. The amount used is 5 to 30 parts by weight per 100 parts by weight of the polyolefin resin; if it is less than 5 parts by weight, it may not be possible to sufficiently suppress the oil absorption swelling of the polyolefin resin, while if it is more than 30 parts by weight, the insulating oil may separate on the sheet surface. The extrusion temperature is preferably about 260 to 320°C. By the above organic silane coating process and laminating process, it is possible to form a sheet-like insulator 1 in which insulating papers 3, 3 are provided on both sides of a polyolefin resin sheet 2, as shown in FIG. As shown in FIG. 2, it is also possible to form a sheet-like insulating paper 1 in which an insulating paper 3 is provided on one side of a polyolefin resin sheet 2 and a plastic film 4 is provided on the other side. Incidentally, in the sheet-like insulator formed by the method of the present invention, the polyolefin resin sheet mixed with hydrocarbon-based insulating oil and the cellulose-based insulating paper can be reliably bonded together, and their adhesive strength is high;
The reason is thought to be as follows. Polyolefin resin in a softened or molten state is thermally decomposed to generate radicals, albeit slightly. The radicalized polyolefin resin and the molecules of the applied organic silane contain -
NH−,
【式】または−SH基の活性基とがラジ
カル反応して、シランがポリオレフイン樹脂にグ
ラフトする。そして、ポリオレフイン樹脂にグラ
フトされたシラン内の極性基Ｘがセルロース系絶
縁紙の水酸基と結合する。例えば、Ｘが−OHの
場合にはセルロースの−OH基と化学反応する
か、又は水素結合を形成する。また、Ｘが−
OCH3、−OC2H5、−OCOCH3等の場合にはこれら
の形で化学結合するか、或いはこれらが加水分解
されて−OH基となつて上記と同様にして結合す
る。このように、ポリオレフイン樹脂シートとセ
ルロース系絶縁紙とがシランを介して結合するた
め、これらの間の接着力もしくは貼り合わせ強度
が向上すると考えられる。
以上説明したように、本発明においては炭化水
素系絶縁油を混和したポリオレフイン樹脂シート
が軟化或いは溶融状態にあるときRSiX3（Ｒは−
NH−、[Formula] or the active group of the -SH group undergoes a radical reaction, and the silane is grafted onto the polyolefin resin. Then, the polar group X in the silane grafted to the polyolefin resin combines with the hydroxyl group of the cellulose insulating paper. For example, when X is -OH, it chemically reacts with the -OH group of cellulose or forms a hydrogen bond. Also, if X is -
In the case of OCH3 , -OC2H5 , -OCOCH3, etc., they are chemically bonded in these forms, or they are hydrolyzed to form -OH groups and bonded in the same manner as above. In this way, since the polyolefin resin sheet and the cellulose-based insulating paper are bonded via the silane, it is thought that the adhesive force or bonding strength between them is improved. As explained above, in the present invention, when the polyolefin resin sheet mixed with hydrocarbon insulating oil is in a softened or molten state, RSiX 3 (R is -
NH−,
ポリプロピレン、ポリブデン−１、ポリ４−メ
チルペンテン−１の各樹脂100重量部当たり20重
量部の重質アルキルベンゼン（JIS−Ｃ−2320、
２種２号）絶縁油を混練したのち、それぞれを押
出ラミネート法により280℃、270℃、300℃の押
出温度においてＴダイで押し出した。そして、ラ
ミネート化させる前に溶融樹脂表面にNH2
（CH2）3Si（OC2H5）3を噴霧法により0.7ｇ／m2塗
布した。そして、上記押出ラミネート法により連
続的に処理し、２本のロールによつてポリオレフ
イン樹脂シート２の両面に厚さ40μのセルロース
系絶縁紙３，３を圧着した。得られたシート状絶
縁体１の厚さは120μであつた。
その後、各シート状絶縁体を120℃の温度で真
空乾燥し、真空下でアルキルベンゼン系の絶縁油
を含浸させ、次いで80℃に20時間放置した後、室
温に放置して冷却させた。
次いで、各シート状絶縁体におけるポリオレフ
イン樹脂シートとセルロース系絶縁紙との接着力
を室温条件下で次のようにして測定した。即ち、
幅15mm、長さ250mmの試験片の片側のセルロース
系絶縁紙を一端より長さ方向に50mm剥離した後、
ここから引張り試験機により更に150mm（合計200
mm）剥離し、この際の引張り強度を測定した。そ
して、平均の引張り強度を接着力（ｇ／幅15mm）
とした。得られた結果を以下の第１表に示す。
なお、比較のため、絶縁油を混和したポリオレ
フイン樹脂シートを有機シランで処理しない場合
にも上記と同様に処理してシート状絶縁体を形成
し、その接着力を上記と同様にして測定した。得
られた結果を次の第１表に併記する。
20 parts by weight of heavy alkylbenzene (JIS-C-2320,
Type 2, No. 2) After kneading the insulating oil, each was extruded using a T-die at extrusion temperatures of 280°C, 270°C, and 300°C using an extrusion lamination method. Then, before laminating, NH 2 is applied to the surface of the molten resin.
(CH 2 ) 3 Si(OC 2 H 5 ) 3 was applied at a rate of 0.7 g/m 2 by a spraying method. Then, it was continuously processed by the extrusion lamination method described above, and cellulose-based insulating papers 3, 3 having a thickness of 40 μm were pressed onto both sides of the polyolefin resin sheet 2 using two rolls. The thickness of the obtained sheet-like insulator 1 was 120μ. Thereafter, each sheet-like insulator was vacuum dried at a temperature of 120°C, impregnated with an alkylbenzene-based insulating oil under vacuum, and then left at 80°C for 20 hours, and then left at room temperature to cool. Next, the adhesive force between the polyolefin resin sheet and the cellulose insulating paper in each sheet-like insulator was measured under room temperature conditions as follows. That is,
After peeling off the cellulose insulating paper on one side of a test piece with a width of 15 mm and a length of 250 mm by 50 mm in the length direction from one end,
From here, the tensile tester further measures 150 mm (total 200 mm).
mm), and the tensile strength at this time was measured. Then, the average tensile strength is the adhesive strength (g/width 15 mm)
And so. The results obtained are shown in Table 1 below. For comparison, a polyolefin resin sheet mixed with insulating oil was treated in the same manner as above without being treated with organic silane to form a sheet-like insulator, and its adhesive strength was measured in the same manner as above. The results obtained are also listed in Table 1 below.
【表】
上記第１表の結果から明らかな如く、本発明の
方法で形成されたシート状絶縁体におけるポリオ
レフイン樹脂シートとセルロース系絶縁紙との接
着力は高いのに対し、比較例１〜３の場合の接着
力は非常に低い。[Table] As is clear from the results in Table 1 above, the adhesive strength between the polyolefin resin sheet and the cellulose insulating paper in the sheet insulator formed by the method of the present invention is high, whereas Comparative Examples 1 to 3 The adhesion strength in this case is very low.
第１図は本発明の方法で形成された一例のシー
ト状絶縁体の縦断面図、第２図は他の例のシート
状絶縁体の縦断面図である。
１……シート状絶縁体、２……ポリオレフイン
樹脂シート、３……セルロース系絶縁紙。
FIG. 1 is a longitudinal sectional view of one example of a sheet-like insulator formed by the method of the present invention, and FIG. 2 is a longitudinal sectional view of another example of a sheet-like insulator. 1... Sheet-shaped insulator, 2... Polyolefin resin sheet, 3... Cellulose-based insulating paper.
Claims (1)
ルロース系絶縁紙とをラミネートするに当たり、
前記シートとしてポリオレフイン樹脂100重量部
当たり５〜30重量部の炭化水素系絶縁油を混合し
た混和物のシートを用い、この混和物シートが軟
化或いは溶融状態にあるときにRSiX3（Ｒは−
NH−、【式】−SH基を１個以上含む炭化水 素基、Ｘは−OH、−OCH3、−OC2H5、−OCOCH3
等の基）の化学式で表わされる有機シランを塗布
した後、セルロース系絶縁紙とラミネートするこ
とを特徴とするシート状絶縁体の製造方法。[Claims] 1. In laminating a sheet mainly made of polyolefin resin and cellulose-based insulating paper,
As the sheet, a sheet of a mixture of 5 to 30 parts by weight of hydrocarbon insulating oil per 100 parts by weight of polyolefin resin is used, and when this mixture sheet is in a softened or molten state, RSiX 3 (R is -
NH-, [Formula] Hydrocarbon group containing one or more -SH groups, X is -OH, -OCH 3 , -OC 2 H 5 , -OCOCH 3
1. A method for producing a sheet-like insulator, which comprises applying an organic silane represented by the chemical formula of
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8248679A JPS567308A (en) | 1979-06-29 | 1979-06-29 | Method of manufacturing sheettlike insulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8248679A JPS567308A (en) | 1979-06-29 | 1979-06-29 | Method of manufacturing sheettlike insulator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS567308A JPS567308A (en) | 1981-01-26 |
| JPS6111419B2 true JPS6111419B2 (en) | 1986-04-02 |
Family
ID=13775830
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8248679A Granted JPS567308A (en) | 1979-06-29 | 1979-06-29 | Method of manufacturing sheettlike insulator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS567308A (en) |
-
1979
- 1979-06-29 JP JP8248679A patent/JPS567308A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS567308A (en) | 1981-01-26 |
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