Takeda Pharmaceutical Company Limited

Wako Pure Chemical Industries, Inc.

Central Glass Company, Limited

Takashi Aoki

Yoshio Hata

Tsutomu Tani

Kohei Yamamoto

Kensuke Hirotaki

Hirokatsu Nagura

A novolak resin including a partial structure represented by —C(CF)H—. In addition, there are provided a photosensitive resin composition containing the above-described novolak resin and a photosensitizing agent. In addition, there is provided an epoxy resin having a partial structure represented by —C(CF)H—. In addition, there is provided a curable resin composition containing the novolak resin or the epoxy resin. In addition, there is provided a cured substance obtained by curing the composition. In addition, there is provided a production method for a novolak resin, including reacting an aromatic compound with fluoral in a presence of an acid catalyst to produce a novolak resin having a partial structure represented by —C(CF)H—. Further, there is provided a production method for an epoxy resin, including an epoxidation step of reacting a novolak resin having a partial structure represented by —C(CF)H— with epihalohydrin in a presence of a base.

Novolak resin, epoxy resin, photosensitive resin composition, curable resin composition, cured substance, electronic device, production method for novolak resin, and production method for epoxy resin

A process for producing a lactic acid polymer of 15,000 to 50,000 in weight-average molecular weight, the content of polymeric materials having not more than about 5,000 in weight-average molecular weight therein being not more than about 5% by weight, characterized by hydrolyzing a high molecular weight lactic acid polymer, placing the resultant solution comprising the hydrolyzed product under a condition capable of precipitating the objective lactic acid polymer, separating the precipitated lactic acid polymer and collecting them. The lactic acid polymer is useful as a matrix for sustained-release preparations. The sustained-release microcapsule preparation encapsulating a physiologically active substance can fully prevent the initial excessive release of the physiologically active substance from the microcapsules and keep a stable release rate over a long period of time.

Lactic acid polymer and process for producing the same

Growing community of inventors

Kawagoe, Japan

Takashi Aoki