Kiichi Hasegawa

New thermosetting resin from Poly(p-vinylphenol) based benzoxazine and epoxy resin

Poly(p-vinylphenol) (VP) based benzoxazine was prepared from VP, formaline, and aniline. The curing behavior of the benzoxazine with the epoxy resin and the properties of the cured resin were investigated. Consequently, the curing reaction did not proceed at low temperatures, but it proceeded rapidly at higher temperatures without a curing accelerator. The reaction induction time or cure time of the molten mixture from VP based benzoxazine and epoxy resin was found to decrease, compared with those from conventional bisphenol A based benzoxazine and epoxy resin. The curing reaction rate of VP based benzoxazine and epoxy resin increased more than that of conventional bisphenol A based benzoxazine and epoxy resin. The properties of the cured resin from neat resins and from reinforced resins with fused silica were evaluated. The cured resins from VP based benzoxazine and epoxy resin showed good heat resistance, mechanical properties, electrical insulation, and water resistance compared to the cured resin from VP and epoxy resin using imidazole as the catalyst.

New thermosetting resin from terpenediphenol-based benzoxazine and epoxy resin

Terpenediphenol-based benzoxazine was prepared from terpenediphenol, formaline, and aniline. Curing behavior of the benzoxazine with epoxy resin and the properties of the cured resin were investigated. Consequently, the curing reaction did not proceed at low temperatures, but it proceeded rapidly at higher temperatures without a curing accelerator. The properties of the cured resin both from neat resins and from reinforced resins with fused silica were evaluated, respectively. The cured resins showed good heat resistance, mechanical properties, electrical insulation, and especially water resistance, compared with the cured resin from bisphenol A type novolac and epoxy resin.

New thermosetting resin from Bisphenol A-based benzoxazine and bisoxazoline

Bisphenol A-based benzoxazine was prepared from bisphenol A, formaline, and aniline. Curing reaction of bisphenol A-based benzoxazine with bisoxazoline and the properties of the cured resin were investigated. Consequently, using triphenylphosphite as a catalyst, for the first time the ring-opening reaction of benzoxazine ring occurred at 170°C, and then the phenolic hydroxyl group generated by the ring-opening reaction of the benzoxazine ring reacted with the oxazoline ring at 200°C. The melt viscosity of the molding compound was kept 0.1–1 Pa · s at 140°C even after 1.5 h, and increased rapidly at 180°C. It was realized that the molding compound showed good flowability below 140°C, curing reaction proceeded above 180°C rapidly. The cured resin from bisphenol A-based benzoxazine and bisoxazoline showed good heat resistance, water resistance, electrical insulation, and mechanical properties, compared with the cured resin from bisphenol A-type novolac and bisoxazoline.

The Effect of the Ortho-Bonding Unit in Novolak on the Photoresist.

ポジ型フォトレジストに含まれるノボラックの内部構造で重要視されているオルト結合体ユニットの効果について, アルカリ現像液に対する溶解挙動から検討を行った. まず, ノボラック中でオルト結合体ユニットを形成すると考えられる低分子化合物 (6P) を合成し, ついで, これを高分子量化して6Pユニットをノボラック中に導入した. その結果, このノボラックからなるレジストは, 従来のレジストに比べ, アルカリ現像液に対する溶解禁止効果 (未露光部) および溶解促進効果 (露光部) が強く発現し, 溶解コントラストが増大した. これにより, レジストのパターンプロファイルが向上し, ノボラック中にオルト結合体ユニットを導入した効果が明確となった. また, ノボラックの高分子成分にオルト結合体ユニットを導入する手段として, この6Pが有用であることがわかった.