JP4670165B2 - Heat resistant resin composition, resin-coated copper foil and laminate using the same - Google Patents

Description

及び、（Ｂ）下記一般式（２）で表されるイソシアヌレート樹脂又はそのプレポリマー
【化４】

を必須成分として含有することを特徴とする耐熱性樹脂組成物である。そして、本発明は、前記耐熱性樹脂組成物を銅箔に塗工してなることを特徴とするＲＣＣであり、さらに前記ＲＣＣを１枚又は２枚以上重ね合わせ加熱加圧してなることを特徴とする積層板又は銅張積層板である。
【０００６】
【発明の実施の形態】
本発明で用いる（Ａ）成分のベンゾシクロブテン樹脂は下記一般式（１）で示される。
【化５】

また、かかる一般式を有するベンゾシクロブテン樹脂をＢステージ化したものも成形性、流動性を調整するために好ましく使用され、本発明の（Ａ）成分に含まれるものである。Ｂステージ化は加熱溶融して行われる。Ｂステージ化したベンゾシクロブテン樹脂とは、数平均分子量３０００〜１４０、０００のものをいう。数平均分子量はＧＰＣを用いて測定する。
ベンゾシクロブテン樹脂は樹脂成分１００重量部中、２０重量部以上９５重量部以下が好ましい。２０重量部未満では比誘電率、誘電正接が十分でないことがあり、また９５重量部を越えるとフローが悪化するようになる。
【０００７】
本発明においてイソシアヌレート樹脂は、シクロブテン樹脂等の欠点を改善する重要な成分である。イソシアヌレート樹脂は耐熱性が高く、カルボニル基を含むため銅箔との密着性が高い。さらに対称性が高い化学構造を有しているため、双極子モーメントが小さくそれほど誘電特性を低下させない。また、反応性も高く成形性に優れている。従って、イソシアヌレート樹脂をシクロブテン樹脂と併用することで特性の優れた樹脂組成物を得ることができる。
本発明で用いる（Ｂ）成分のイソシアヌレート樹脂は下記一般式（２）で示される。
【化６】

また、かかる一般式を有するイソシアヌレート樹脂をプレポリマー化したものも成形性、流動性を調整するために好ましく使用され、本発明の（ Ｂ ）成分に含まれるものである。
イソシアヌレート樹脂は樹脂成分１００重量部中、５重量部以上４０重量部以下が好ましい。５重量部未満では耐クラック性、金属密着性改善の効果が得られず、また４０重量部を越えると比誘電率、誘電正接が十分でないことがある。
【０００８】
本発明の樹脂組成物は種々の形態で利用される。通常、ワニスの形態であるが、銅箔に塗工する際には通常溶剤に溶解したワニスの形で使用ことが含浸性の点で好ましい。用いられる溶媒は組成に対して良好な溶解性を示すことが望ましいが、悪影響を及ばさない範囲で貧溶媒を使用しても構わない。良溶媒としては、メチルエチルケトン、シクロヘキサノン等が挙げられる。
【０００９】
本発明の樹脂組成物を溶剤に溶解して得られるワニスを、銅箔に塗工させ８０℃以上２００℃以下で乾燥させることによりＲＣＣを得ることが出来る。
かかるＲＣＣは加熱加圧して積層板又は銅張積層板を製造することに用いられる。本発明の樹脂組成物は耐熱性、誘電特性に優れた樹脂組成物であり、特に、プリント配線板用の積層等に好適に使用されるものである。
【００１０】
本発明の樹脂組成物は、上述したベンゾシクロブテン樹脂とイソシアヌレート樹脂を必須成分として含有するが、本発明の目的に反しない範囲において、その他の樹脂、硬化促進剤、カップリング剤、難燃剤、フィラー、その他の成分を添加することは差し支えない。
【００１１】
【実施例】
ベンゾシクロブテン樹脂として、ジビニルシロキサン−ビスベンゾシクロブテン（プレポリマー化したもの。重量平均分子量１４００００、ダウケミカル社製サイクロテンＸＵＲ）８０重量部、イソシアヌレート樹脂としてトリアクリルイソシアヌレート樹脂（東亞合成（株）製アロニックスＭ−３１５）２０重量部をメシチレンに溶解し、不揮発分濃度５０重量％となるようにワニスを調整した。
このワニスを用いて、銅箔（厚さ０．０１８ｍｍ、古河サーキットフォイル（株）製）にワニスを厚さ０．１２ｍｍで塗工し、１５０℃の乾燥機炉で１０分、１７０℃の乾燥機炉で１０分乾燥させ、樹脂厚０．４ｍｍのＲＣＣを作成した。
銅箔を両面に張った両面銅張積層板の銅箔表面を黒化処理（酸化銅形成）した後還元したものをコアとして、その両面に上記ＲＣＣを１７０℃１時間、２００℃２時間で加熱加圧接着し、熱硬化させることにより試験用銅張積層板を作成した。また、これと同時に上記ＲＣＣを２枚重ね合わせたものを同様に１７０℃１時間、２００℃２時間で加熱加圧接着し、熱硬化後酸で表面銅箔をエッチングすることにより除去してレジン板を作成した。
【００１２】
得られた試験用銅張積層板については半田耐熱性及びピール強度を測定した。半田耐熱性、ピール強度についてはＪＩＳ Ｃ ６４８１に準じて測定し、半田耐熱性は煮沸２時間の吸湿処理を行った後、２６０℃の半田槽に１２０秒浸漬した後の外観異常の有無を調べた。レジン板については、ガラス転移点、誘電率、誘電正接を測定した。ガラス転移点はレオメトリックス製 ＲＤＳ−７７００を用いて、昇温速度３℃／ｍｉｎ、周波数１Ｈｚで測定した。誘電率、誘電正接の測定はＪＩＳ Ｃ ６４８１に準じて行い、周波数１ＭＨｚの静電容量を測定して求めた。評価結果を表１に示す。実施例に示す銅張積層板はいずれも誘電率、誘電正接が低く、耐熱性、半田耐熱性、金属密着性に優れていることがわかる。
【００１３】
【表１】

表の注
（１）ジビニルシロキサン−ビスベンゾシクロブテン（プレポリマー化：重量分子量１４００００）
【００１４】
【発明の効果】
本発明の耐熱性組成物は、プリント配線材料に適用された場合、高耐熱性を有し、誘電率が低い特性を有し、かつ金属密着性に優れた特性を有している。従って、今後、小型情報処理機器のプリント配線板に最適な樹脂組成物を提供するものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin composition excellent in heat resistance and dielectric properties, a copper foil with resin, and a laminate. Especially preferably, it is used suitably for the use of a high frequency circuit board.
[0002]
In recent years, portable electronic devices such as notebook personal computers and mobile phones have been required to be lighter and smaller. Therefore, printed circuit boards on which electronic devices such as CPUs and LSIs are mounted are also reduced in size and weight. Needed naturally. In order to achieve a reduction in size and weight, it is necessary to minimize the thickness of the insulating resin layer, the printed wiring width and the distance between wirings, reduce the through-hole diameter, and reduce the plating thickness. Here, if the plating thickness is reduced, plating cracks may occur during thermal shock, and heat resistance is required. At the same time, speeding up of these information processing devices is also demanded, and the CPU clock frequency is increasing. For this reason, a high signal propagation speed is required, and a printed board having a low dielectric constant and a low dielectric loss tangent is required to realize this.
[0003]
A benzocyclobutene resin is used as a resin having excellent heat resistance and excellent dielectric properties (for example, Japanese Patent Application Laid-Open No. 2000-21872). Since the benzocyclobutene resin does not generate a functional group having a high polarizability such as a hydroxyl group by the curing reaction, the dielectric property is very excellent. However, since there is no such polar group, there is a defect that the adhesiveness with the copper foil is lacking.
[0004]
[Problems to be solved by the invention]
The present invention has been made as a result of studies to solve such problems. By using a benzocyclobutene resin and an isocyanurate resin in combination, heat resistance, dielectric properties, metal adhesion, crack resistance, and moldability are improved. An excellent resin composition, a copper foil with resin (hereinafter abbreviated as RCC), and a laminate obtained from the RCC are provided.
[0005]
[Means for Solving the Problems]
The present invention relates to (A) a benzocyclobutene resin represented by the following general formula (1):

And (B) an isocyanurate resin represented by the following general formula (2) or a prepolymer thereof:

Is contained as an essential component. And this invention is RCC characterized by apply | coating the said heat resistant resin composition to copper foil, Furthermore, the said RCC is laminated | stacked and heat-pressed 1 sheet or 2 sheets or more, It is characterized by the above-mentioned. It is a laminated board or a copper clad laminated board.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The (A) component benzocyclobutene resin used in the present invention is represented by the following general formula (1).
[Chemical formula 5]

A B-staged benzocyclobutene resin having such a general formula is also preferably used for adjusting moldability and fluidity, and is included in the component (A) of the present invention. B-staging is performed by heating and melting. B-staged benzocyclobutene resin refers to those having a number average molecular weight of 3000 to 140,000. The number average molecular weight is measured using GPC.
The benzocyclobutene resin is preferably 20 to 95 parts by weight in 100 parts by weight of the resin component. If it is less than 20 parts by weight, the relative dielectric constant and dielectric loss tangent may not be sufficient, and if it exceeds 95 parts by weight, the flow will deteriorate.
[0007]
In the present invention, the isocyanurate resin is an important component for improving defects such as cyclobutene resin. The isocyanurate resin has high heat resistance, and since it contains a carbonyl group, it has high adhesion to the copper foil. Furthermore, since it has a highly symmetric chemical structure, the dipole moment is small and the dielectric properties are not degraded so much. Moreover, it has high reactivity and excellent moldability. Therefore, a resin composition having excellent characteristics can be obtained by using an isocyanurate resin in combination with a cyclobutene resin.
The isocyanurate resin of component (B) used in the present invention is represented by the following general formula (2).
[Chemical 6]

Moreover, what prepolymerized isocyanurate resin which has this general formula is preferably used in order to adjust a moldability and fluidity | liquidity, and is contained in the (B) component of this invention.
The isocyanurate resin is preferably 5 to 40 parts by weight per 100 parts by weight of the resin component. If it is less than 5 parts by weight, the effect of improving crack resistance and metal adhesion cannot be obtained, and if it exceeds 40 parts by weight, the relative permittivity and dielectric loss tangent may not be sufficient.
[0008]
The resin composition of the present invention is used in various forms. Usually, it is in the form of a varnish, but when applied to a copper foil, it is preferable to use it in the form of a varnish usually dissolved in a solvent in terms of impregnation properties. The solvent used preferably has good solubility in the composition, but a poor solvent may be used as long as it does not adversely affect the composition. Examples of the good solvent include methyl ethyl ketone and cyclohexanone.
[0009]
RCC can be obtained by coating a varnish obtained by dissolving the resin composition of the present invention in a solvent on a copper foil and drying at 80 ° C. or higher and 200 ° C. or lower.
Such RCC is used for producing a laminate or a copper clad laminate by heating and pressing. The resin composition of the present invention is a resin composition excellent in heat resistance and dielectric properties, and is particularly suitably used for lamination for printed wiring boards.
[0010]
The resin composition of the present invention contains the above-described benzocyclobutene resin and isocyanurate resin as essential components, but other resins, curing accelerators, coupling agents, flame retardants, as long as they do not contradict the purpose of the present invention. , Fillers, and other ingredients can be added.
[0011]
【Example】
Divinylsiloxane-bisbenzocyclobutene (prepolymerized as a benzocyclobutene resin, weight average molecular weight 140000, cycloten XUR manufactured by Dow Chemical Company) 80 parts by weight, triacryl isocyanurate resin (Toagosei Co., Ltd.) Aronix M-315 manufactured by Co., Ltd.) 20 parts by weight was dissolved in mesitylene, and the varnish was adjusted so that the nonvolatile content concentration was 50% by weight.
Using this varnish, the varnish was applied to a copper foil (thickness 0.018 mm, manufactured by Furukawa Circuit Foil Co., Ltd.) at a thickness of 0.12 mm, and dried at 170 ° C. for 10 minutes in a dryer oven at 150 ° C. It was dried for 10 minutes in a machine furnace to prepare RCC having a resin thickness of 0.4 mm.
The surface of the copper foil of the double-sided copper clad laminate with the copper foil stretched on both sides was blackened (copper oxide formation) and then reduced, and the above RCC was applied to both sides at 170 ° C for 1 hour and 200 ° C for 2 hours. A test copper-clad laminate was prepared by heat-pressure bonding and thermosetting. At the same time, two sheets of the above-mentioned RCCs are similarly bonded by heating and pressing at 170 ° C. for 1 hour and 200 ° C. for 2 hours. A board was created.
[0012]
The obtained copper clad laminate for test was measured for solder heat resistance and peel strength. Solder heat resistance and peel strength were measured according to JIS C 6481. Solder heat resistance was examined for the presence or absence of abnormal appearance after immersion in a solder bath at 260 ° C. for 120 seconds after moisture absorption treatment for 2 hours. It was. For the resin plate, the glass transition point, dielectric constant, and dielectric loss tangent were measured. The glass transition point was measured using RDS-7700 manufactured by Rheometrics at a heating rate of 3 ° C./min and a frequency of 1 Hz. The dielectric constant and dielectric loss tangent were measured according to JIS C 6481 and measured by measuring the capacitance at a frequency of 1 MHz. The evaluation results are shown in Table 1. It can be seen that the copper clad laminates shown in the examples all have low dielectric constant and dielectric loss tangent and are excellent in heat resistance, solder heat resistance, and metal adhesion.
[0013]
[Table 1]

Notes to Table (1) Divinylsiloxane-bisbenzocyclobutene (prepolymerization: weight molecular weight 140000)
[0014]
【The invention's effect】
When applied to printed wiring materials, the heat resistant composition of the present invention has high heat resistance, low dielectric constant, and excellent metal adhesion. Accordingly, in the future, the present invention will provide a resin composition that is optimal for printed wiring boards of small information processing equipment.

Claims (3)

(A) A benzocyclobutene resin represented by the following general formula (1)

And (B) an isocyanurate resin represented by the following general formula (2) or a prepolymer thereof:

Is a heat-resistant resin composition characterized by being an essential component. A resin-coated copper foil obtained by coating the copper foil with the resin composition according to claim 1. A heat-resistant laminate or a copper-clad laminate obtained by heating and pressing one or more of the resin-coated copper foils according to claim 2.