Rohm Co., Ltd.

Mitsui Minings & Melting Co., Ltd.

Osaka Gas Company Limited

Satosen Co., Ltd.

Katsuyuki Takahashi

Yasuo Kanetake

Yuta Okawauchi

Mitsuaki Yamada

Katsuhide Okimi

Yuji Kageyama

Norio Nagano

A multilayer capacitor includes a laminate having a first side surface and a second side surface, a first side covering portion covering the first side surface, and a second side covering portion covering the second side surface. The laminate includes first conductor layers, second conductor layers, dielectric layers and insulating layers laminated in the z direction. Each first conductor layer is connected to the first side covering portion and spaced apart from the second side covering portion. Each second conductor layer is connected to the second side covering portion and spaced apart from the first side covering portion. The insulating layers have a lower dielectric strength than the dielectric layers. Each dielectric layer is sandwiched between a first conductor layer and a second conductor layer. The insulating layers include one sandwiched between two first conductor layers and one sandwiched between two second conductor layers.

Multilayer capacitor

A fluorene derivative of high purity is produced by reacting fluorenone with phenoxyethanol in the presence of a sulfuric acid-thiol catalyst system, dissolving the reaction mixture in a lower aliphatic alcohol and adding water to the resulting solution for precipitation of 9,9-bis(4-(2-hydroxyethoxy)phenyl)fluorene [fluorene derivative]. A fluorene derivative of still higher purity is obtained by recrystallization from a lower aliphatic alcohol. In accordance with this invention, a fluorene derivative can be produced advantageously on a commercial scale without incurring any appreciable loss of fluorenone, in good yield, with high efficiency and in a reduced production time.

Method of preparing a fluorene derivative and the method of purifying

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Osaka, Japan

Katsuyuki Takahashi