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At present, the lithium ion secondary battery is necessary as an energy storage device for cellular phones, notebook computers and so on. The key to even further disseminate LIB was to add a safety function to prevent thermal abuse; therefore, the separator was required to have the safety function. The Asahi Kasei Corporation has carried out the development of the safety function of the separator and succeeded in controlling the pore size of the separator for improving the performance of LIBs.

旭化成（株）知的財産部・技術情報センターは，当社の種々の組織に分散して存在していた調査機能を，1998年に知的財産部の中に統合・一元化して発足した。技術情報センターは，全社に対する高品質な調査情報の提供と調査啓蒙を主なミッションとしている。その中でも特に，特許情報の戦略データベース（SDB：Strategic DataBase）構築活動は，当社における知財戦略立案と知的財産権の戦略的活用の要との認識の下，発足以来一貫して取り組んできた業務である。本報では，当センターによるSDB構築活動の実情を紹介する。基盤整備，普及，定着の三つの活動期にわたる活動を通じてできあがったSDBの全体像と，その成果について概観し，次いで，この三期それぞれの活動方針，導入の際の課題，その対応策を具体例を交えながら紹介する。

We have studied polyethylene micro-porous membranes as a lithium ion secondary battery separator. We have focused on the relationship between pore structure and separator properties. The separator with large pore size has better cycle properties. The separator made using low melting point polymers has a low fusing temperature.

Hydrolytic alkyl–oxygen bond fission of optically active 1-methylheptyl trifluoromethanesulphonate is extensively retarded by micelles of cetyltrimethyl-ammonium bromide and sodium lauryl sulphate and proceeds with predominant retention of configuration.

The title compounds (Ia)–(IIIa) were subjected to solvolysis in the presence of sodium phenoxide in pure phenol or in phenol-benzene (1 : 1 w/w) as solvent. Both polarimetric and titrimetric rate constants (Kp and Kt) decrease in the order (Ia) > (IIa) > (IIIa); Kp values for (Ia) and (IIa) exceed those for Kt over the whole range of concentration of added sodium phenoxide, whereas Kp and Kt for (IIIa) coincide with each other. The major products, the phenyl ethers (Ib)–(IIIb), show net retention of configuration; the extent of retention was 16.6% for (Ib) in phenol-benzene at 25°, 34.5% for (IIb), and 90.0% for (IIIb) in phenol at 125°, respectively. The C-alkylated products, o- and p-1-phenylethylphenols, are formed to a small extent only and undergo net inversion with predominant racemization in the phenolysis of (IIa). Variations in the yield and in the extent of retention for (Ib)–(IIIb) have been examined for various concentrations of added sodium phenoxide; variations in the optical rotation of recovered substrate and those in the extent of retention of the phenyl ether have also been determined in the course of each phenolysis. On the basis of this evidence, the mechanisms and steric courses of these reactions are discussed. Maximum rotations of the phenyl ethers (Ib)–(IIIb) and 1-arylethanols (Ic)–(IIIc) have been determined by chemical or n.m.r. shift reagent methods; the absolute configurations of (IIIb) and (IIIc) have also been assigned by the use of a chemical method.