JPH07290633A - Single-sided copper clad laminated sheet - Google Patents

Abstract

PURPOSE:To reduce warpage and distortion without damaging various characteristics in a structurally non-uniform single-sided copper clad laminated sheet obtained by arranging copper foil on the single surface of a base material layer consisting of a fiber base material and a thermosetting resin through a resin layer having specific thickness and containing no fiber base material. CONSTITUTION:Copper foil is arranged on the single surface of a base material layer consisting of a fiber base material and a thermosetting resin through a resin layer having a thickness of 5mum or more and containing no fiber base material. As the thermosetting resin, all of resins generally used in a laminated sheet such as a phenol resin, an epoxy resin or the like are used and the resin used in a prepreg is desirably same to the resin used in the resin layer between the copper foil and the base material. As the base material, all of fabrics or nonwoven fabrics used in the laminated sheet and composed of a glass fiber, a synthetic fiber or the like are used. The resin layer between the copper foil and the base material is provided in order to coat the surface coming into contact with the copper foil of the prepreg or to enhance the resin content of the prepreg coming into contact with the copper foil as compared with other prepreg. The base material, the resin layer and the copper foil are superposed one upon another and molded under heating and pressure to produce a single-sided copper clad laminated sheet.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、プリント配線板用とし
て使用される、そりの少ない片面銅張積層板のに関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-sided copper-clad laminate having a small amount of warpage, which is used for printed wiring boards.

【０００２】[0002]

【従来の技術】プリント配線板の製造及び部品実装の自
動化の進展に伴いそり、ねじれの少ない銅張積層板が望
まれる。2. Description of the Related Art With the progress of automation of printed wiring board manufacturing and component mounting, there is a demand for a copper clad laminate having less warpage and warpage.

【０００３】銅張積層板のそり、寸法変化は、積層成形
時に生ずる応力が歪みとして残り、それがプリント配線
板製造時の加熱工程で解放され発生する。そこでこの歪
みの発生を低減するため、減圧雰囲気下で低圧成形する
ことや、銅はくの熱膨張係数に近い熱膨張係数を有する
鏡面板を使用し、熱膨張係数の差から鏡面板と銅はくの
間に生ずる熱的応力を低減すること等が行われている。The warpage and dimensional change of the copper-clad laminate are caused by the stress generated during lamination and remaining as strain, which is released in the heating step during manufacturing of the printed wiring board. Therefore, in order to reduce the occurrence of this distortion, low pressure molding is performed in a reduced pressure atmosphere, and a mirror surface plate having a coefficient of thermal expansion close to that of copper foil is used. For example, the thermal stress generated during the foil is reduced.

【０００４】また、積層成形時に生じた歪みを除去する
方法として、積層板用樹脂のガラス転移温度以上の温度
で一定時間アニールが行われることもある。Further, as a method of removing the strain generated during the lamination molding, annealing may be performed for a certain period of time at a temperature not lower than the glass transition temperature of the resin for the laminated plate.

【０００５】[0005]

【発明が解決しようとする課題】両面銅張積層板の場合
であれば上記の対策によりそり、ねじれの低減は可能で
ある。しかし片面銅張積層板の場合構造的に不均一であ
り、成形時銅はくと樹脂含浸基材が接着された時点で積
層板の表裏に熱膨張係数の差が生じる。このため単に成
形圧力の低圧化やアニール等を行い成形歪みの低減を図
っても、そり、ねじれの低減に効果は少ない。In the case of a double-sided copper-clad laminate, warping and twisting can be reduced by the above measures. However, the one-sided copper-clad laminate is structurally non-uniform, and a difference in thermal expansion coefficient occurs between the front and back sides of the laminate when the copper foil and the resin-impregnated base material are bonded during molding. Therefore, even if the molding pressure is simply reduced or annealing is performed to reduce the molding strain, the effect of reducing the warpage and the twist is small.

【０００６】本発明は、このように構造的に不均一な片
面銅張積層板について他の諸特性を損なうことなく、そ
り、ねじれを少なくすることを目的とする。It is an object of the present invention to reduce warpage and twist of a single-sided copper clad laminate having such a structurally non-uniform structure without impairing other characteristics.

【０００７】[0007]

【課題を解決するための手段】本発明は、繊維基材と熱
硬化性樹脂とからなる基材層の片側に、厚さが５μｍ以
上で繊維基材を含まない樹脂層を介して銅はくを配して
なることを特徴とするものである。According to the present invention, copper is provided on one side of a base material layer comprising a fiber base material and a thermosetting resin via a resin layer having a thickness of 5 μm or more and containing no fiber base material. It is characterized in that it is made by arranging Ku.

【０００８】使用する樹脂は、フェノール樹脂、エポキ
シ樹脂、ポリエステル樹脂、ポリイミド樹脂等一般的に
積層板に使用する種類全般であるが、プリプレグに使用
する樹脂と銅はくと基材間の樹脂層に使用する樹脂は、
同種類であることが望ましい。[0008] The resin to be used is a general type generally used for laminated boards such as phenol resin, epoxy resin, polyester resin and polyimide resin, but the resin layer between the resin used for the prepreg and the copper foil and the base material. The resin used for
It is desirable that they are of the same type.

【０００９】使用する基材は、ガラス繊維、合成繊維、
セルロース系繊維等の積層板用として使用される織布、
あるいは不織布全般である。The substrate used is glass fiber, synthetic fiber,
Woven fabric used for laminated boards such as cellulosic fibers,
Alternatively, it is a non-woven fabric in general.

【００１０】銅はくと基材の間の樹脂層は、銅はくある
いはプリプレグの銅はくに接する面に樹脂を塗布するこ
とや、銅はくに接するプリプレグの樹脂分を他のプリプ
レグより高めることにより設け、その後これらを積み重
ね加熱加圧成形して片面板を製造する。In the resin layer between the copper foil and the base material, a resin is applied to the surface of the copper foil or prepreg that contacts the copper foil, or the resin content of the prepreg that contacts the copper foil is higher than that of other prepregs. After that, these are stacked and heat-pressed to produce a single-sided plate.

【００１１】樹脂層の厚みは５〜３０μｍが好ましく、
これより薄いと基材の拘束を抑制するのに不十分であ
り、３０μｍを越えると、表裏で樹脂量の差を生じ効果
が低減する。The thickness of the resin layer is preferably 5 to 30 μm,
If it is thinner than this, it is insufficient to restrain the restraint of the base material, and if it exceeds 30 μm, a difference in resin amount occurs between the front and back, and the effect is reduced.

【００１２】[0012]

【作用】片面銅張積層板のそりの発生原因と本発明のそ
り低減作用との関係を次に説明する。銅張積層板の材料
となる樹脂含浸基材、銅はくはそれぞれ異なる熱膨張係
数を有する。銅張積層板の製造工程において、加熱時で
はこれら材料に熱膨張係数の差があっても、基材含浸の
樹脂が溶融して流動するため歪みは残りにくい。しか
し、これら材料が一体化した冷却過程では、銅はくと基
材との熱膨張係数の違いから積層板の表裏で収縮量差が
発生する。The relationship between the cause of warpage of the single-sided copper-clad laminate and the warpage reducing effect of the present invention will be described below. The resin-impregnated base material and the copper foil, which are materials for the copper-clad laminate, have different thermal expansion coefficients. In the manufacturing process of a copper clad laminate, even if there is a difference in the coefficient of thermal expansion between these materials during heating, the resin impregnated into the base material melts and flows, and distortion is unlikely to remain. However, in the cooling process in which these materials are integrated, a difference in thermal expansion coefficient between the copper foil and the base material causes a difference in shrinkage amount between the front and back surfaces of the laminated plate.

【００１３】ガラス織布基材エポキシ樹脂片面銅張積層
板を例にとると、銅はくが１７ｐｐｍの係数で収縮する
のに対し、樹脂含浸基材は基材方向にガラス転移温度ま
では８．０〜１０．０ｐｐｍの係数で収縮しガラス転移
温度以下の温度から１６．０〜１７．０ｐｐｍの係数で
収縮する。従って積層工程が終了した時点で銅はくの方
が樹脂含浸基材に比べ収縮量が大きくなる。この傾向は
他の織布基材や樹脂を使用した銅張積層板でも同様であ
る。このため片面銅張積層板では、離型面に比べ銅はく
接着面の方が収縮量が大きくなり銅はく面が凹となるそ
りが発生する。Taking a glass woven fabric substrate epoxy resin single-sided copper clad laminate as an example, the copper foil shrinks with a coefficient of 17 ppm, whereas the resin-impregnated substrate has a glass transition temperature of 8 up to the glass transition temperature. It shrinks with a coefficient of 0.0 to 10.0 ppm and shrinks with a coefficient of 16.0 to 17.0 ppm from a temperature below the glass transition temperature. Therefore, the amount of shrinkage of the copper foil becomes larger than that of the resin-impregnated base material when the laminating process is completed. This tendency is the same for copper-clad laminates using other woven fabric base materials and resins. Therefore, in the single-sided copper-clad laminate, the amount of shrinkage on the copper foil bonding surface is larger than that on the release surface, and warpage occurs in which the copper foil surface is concave.

【００１４】このそりは、樹脂のガラス転移温度以上の
温度領域における銅はくと樹脂含浸基材の収縮量の差か
ら発生しているが、銅はくと樹脂の間だけで考えると、
樹脂はガラス転移温度以上の温度では自由に塑性変形を
することができ、銅はくと収縮量の差が生じても、それ
が歪みとなって残ることは無い。しかし、従来法で製造
した銅張積層板では、銅はくと基材間の樹脂層が薄く、
銅はくの粗化面により基材が拘束されるため、弾性率の
大きい銅はくの動きが塑性変形をしない基材に作用し、
そりが発生する。そこで本発明の様に銅はくと基材の間
に樹脂層を設け、銅はく粗化面による基材の拘束が起こ
らないようにすることで、そりを低減することが可能と
なる。This warpage is caused by the difference in shrinkage between the copper foil and the resin-impregnated base material in the temperature range above the glass transition temperature of the resin. Considering only between the copper foil and the resin,
The resin can be freely plastically deformed at a temperature equal to or higher than the glass transition temperature, and even if a difference in shrinkage amount occurs with copper foil, it does not remain as strain. However, in the copper clad laminate manufactured by the conventional method, the resin layer between the copper foil and the base material is thin,
Since the base material is constrained by the roughened surface of the copper foil, the movement of the copper foil with a large elastic modulus acts on the base material that does not undergo plastic deformation,
A sled occurs. Therefore, as in the present invention, a resin layer is provided between the copper foil and the base material to prevent the copper foil roughened surface from restraining the base material, whereby warpage can be reduced.

【００１５】[0015]

【実施例】【Example】

実施例１ ブロム化エポキシ樹脂１００部（重量部、以下同じ）、
ジシアンジアミド３部、硬化促進剤として２−エチル−
４−メチルイミダゾール０．１７部をＮ，Ｎ−ジメチル
ホルムアミド２５部、メチルセルソルブ２５部に溶かし
てワニスを得た。このワニスを７６２８タイプのガラス
クロスに樹脂分４２±２％となるように含浸乾燥してプ
リプレグＡを得た。さらに、厚み３５μｍの電解銅はく
に上記ワニスを樹脂層の厚みが２０μｍとなるように塗
布乾燥して、樹脂付き銅はくＡを得た。Example 1 100 parts of brominated epoxy resin (parts by weight, the same applies hereinafter),
Dicyandiamide 3 parts, 2-ethyl- as a curing accelerator
0.17 parts of 4-methylimidazole was dissolved in 25 parts of N, N-dimethylformamide and 25 parts of methyl cellosolve to obtain a varnish. This varnish was impregnated into a 7628 type glass cloth so as to have a resin content of 42 ± 2% and dried to obtain a prepreg A. Further, the above varnish was applied to an electrolytic copper foil having a thickness of 35 μm so that the resin layer had a thickness of 20 μm, and dried to obtain a resin-coated copper foil A.

【００１６】このプリプレグＡを３枚と銅はくＡを重ね
離型用のトリアセテートフィルムを配しプレス圧４ＭＰ
ａ、１７５℃で９０分間加熱加圧した後冷却し、板厚
０．６ｍｍの片面銅張積層板を得た。Three pieces of this prepreg A and copper foil A are stacked on each other, and a triacetate film for release is arranged, and the press pressure is 4MP.
a, heated and pressurized at 175 ° C. for 90 minutes and then cooled to obtain a single-sided copper-clad laminate having a plate thickness of 0.6 mm.

【００１７】実施例２ 銅はくＡのかわりに、樹脂層の厚みを４μｍとした銅は
くを使用した以外は実施例１と同様にして板厚０．６ｍ
ｍの片面銅張積層板を得た。Example 2 Instead of the copper foil A, a copper foil having a resin layer thickness of 4 μm was used in the same manner as in Example 1 except that the plate thickness was 0.6 m.
A single-sided copper clad laminate of m was obtained.

【００１８】実施例３ 銅はくＡのかわりに、樹脂層の厚みを３５μｍとした銅
はくを使用した以外は実施例１と同様にして板厚０．６
ｍｍの片面銅張積層板を得た。Example 3 In place of the copper foil A, a copper foil having a resin layer thickness of 35 μm was used in the same manner as in Example 1 except that the plate thickness was 0.6.
A single-sided copper clad laminate having a size of mm was obtained.

【００１９】比較例 実施例１で得たプリプレグＡを３枚重ね、片面に樹脂層
の無い通常の３５μｍを配し、離型にトリアセテートフ
ィルムを使用して、実施例１と同様の積層条件で板厚
０．６ｍｍの片面銅張積層板を得た。Comparative Example Three prepregs A obtained in Example 1 were stacked, a normal 35 μm without a resin layer was placed on one side, and a triacetate film was used for release, under the same lamination conditions as in Example 1. A single-sided copper-clad laminate having a plate thickness of 0.6 mm was obtained.

【００２０】上記実施例及び比較例で得た銅張積層板か
ら４００×３００ｍｍの試験片を作成し、これについて
そり試験を行った。そりは、残銅率５０％の模擬パター
ンを形成し、四隅の最大はね上がりをダイヤルゲージで
測定した。測定は、試験片切断後、パターンエッチング
後、１４０℃で３０分間加熱後について実施した。A 400 × 300 mm test piece was prepared from the copper clad laminates obtained in the above Examples and Comparative Examples, and a warpage test was conducted on the test piece. The sled formed a simulated pattern with a residual copper rate of 50%, and the maximum bulges at the four corners were measured with a dial gauge. The measurement was performed after cutting the test piece, after pattern etching, and after heating at 140 ° C. for 30 minutes.

【００２１】試験結果を表１に示す。The test results are shown in Table 1.

【００２２】[0022]

【表１】 （単位：ｍｍ）[Table 1] (Unit: mm)

【００２３】[0023]

【発明の効果】本発明によれば、切断後、パターン形成
後、加熱後、いずれの時点においても比較例に比べそり
は小さなものとなる。According to the present invention, the warpage is smaller than that of the comparative example at any time after cutting, after pattern formation, and after heating.

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 繊維基材と熱硬化性樹脂とからなる基材
層の片側に、厚さが５μｍ以上で繊維基材を含まない樹
脂層を介して銅はくを配してなる片面銅張積層板。1. A single-sided copper having a copper foil disposed on one side of a base material layer made of a fiber base material and a thermosetting resin with a resin layer having a thickness of 5 μm or more and containing no fiber base material interposed therebetween. Upholstered laminate.