Kao Corporation

Hiroshi Kawamukai

Takashi Oda

Seiichi Miyanaga

Yasushi Kajihara

Kenichi Ueyama

Katsuhiko Rindo

Hideyuki Hanazawa

Masaaki Moriyama

The present invention provides a process for efficiently obtaining polyethers having its high degree of polymerization by easily polymerizing substituted epoxides which could hardly or could not be made so far to provide a high degree of polymerization. That is, a polyether is obtained by a process which comprises ring-opening-polymerizing at least one substituted epoxide, except for propylene oxide and epihalohydrin, in the presence of a rare earth metal compound represented by the formula (I) and a reducing compound:Wherein M represents a rare earth element selected from Sc, Y and lanthanide, and L, Land Lare same as or different from each other and each of them represents an oxygen-binding ligand.

Process for producing polyether

Polyether polymer, preparation process and use thereof

A recording medium, showing sufficient resistance to contamination and having excellent reproducing characteristics, comprises a film provided on a surface thereof and this film comprises a copolymer formed by polymerizing a composition which comprises a compound A having a (meth)acryloyl group and a reactive antistatic agent B having a quaternary ammonium salt group, an alkylene glycol chain, a hydrocarbon group of which carbon number is four or more and a copolymerizable group.

Recording medium

Growing community of inventors

Wakayama, Japan

Hiroshi Kawamukai