Knc Laboratories Co., Ltd.

Katsutoshi Hirose

Hiroya Koyama

Yoshihiro Takagi

Kimihiro Kamasaka

Yoshihiro Ichihara

Hidekazu Imahori

Sota Kurita

Naoshi Kai

Daisuke Yoshihara

Taro Sasabe

Yoshinori Sawashita

There is provided a process for producing a concentrated solution of quaternary ammonium hydroxide which is characterized in that quaternary ammonium hydroxide in a form of water-containing crystals or of an aqueous solution is mixed with a water-soluble organic solvent selected from the group consisting of glycol ether, glycol and triol and the resulting mixed solution is subjected to a thin-film distillation in vacuo so as to evaporate the low boiling material. In accordance with this process, a concentrated solution of quaternary ammonium hydroxide having low water content is able to be easily produced.

Process for producing a concentrated solution for a photoresist-stripping liquid having low water content

The present invention provides a novel intermediate for synthesizing vitamin D derivatives by using a less expensive material. That is, the present invention provides a compound which is synthesized by using carvone as a starting material and which is represented by the following formulae. 

Intermediates for synthesis of vitamin D derivatives

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Hyogo, Japan

Katsutoshi Hirose