酸化チタン樹脂分散層の電子写真特性を研究した．ルチル型酸化チタンと三つのよく知られた高分子（ポリ酢酸ビニル，ポリ塩化ビニル，ポリスチレン）を使用した．測定はコロナ帯電特性；すなわち，分散層の電気抵抗，静電容量，表面電位の立ち上り，暗減衰，光減衰，前露光疲労度らについておこなった．これらの結果から等価回路による解析が表面電位の立ち上りや暗減衰速度の解釈に定性的に成立することがわかった．さらには，暗減衰における表面電位の対数が，初期においては時間の立方根に比例し，次の段階では時間の平方根に比例して減少することがわかった．そこで表面電位の暗減衰の機構について考察をおこなった．

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The photocurrent of dye-sensitized poly-N-vinylcarbazole (PNVC) films was measured in the wavelength range between 360 and 800 mμ. The dyes used were a triaryl carbonium salt, a benzopyrylium salt, and crystal violet. These deys were found to enhance the photo-carriers (holes) in the films both at the first excitation band of PNVC and at the excitation band of the dyes. From this fact, it is concluded that holes are generated by two processes; the first process is that electrons in the valence band of PNVC transfer to photo-excited dyes ahd the second is that photo-excited electrons in PNVC transfer to dyes.
The triaryl carbonium salt which has OCH₃ radicals in place of N(CH₃)₂ radicals in crystal violet was found to show remarkably higher sensitization effect than crystal violet. This is conjectured as follows; the OCH₃ radicals lower the energy of π-electorons and hence, make the dye more acceptor-like.
The decay time of surface voltage was observed to be about 3 seconds at 3 μW/cm² illumination on the surface, where the decay time was defined as a time of the surface voltage dropping to a half to its initial value and the spectrum of the light was matched to the absorption of the dye.

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The study was carried out mainly on the transfer utilizing a roller applied by a d. c. potential for the purpose of making the mechanism of electrostatic powder image transfer in electrophotography clear.
Transfer ratios and characteristics by this method were studied in detail.
Electrofax paper was used as sample paper, and normal paper was selected to be trans-ferred on.
Measurement of the transfer ratios was shown by density method instead of a toner weight method from the viewpoint of practical use.
Our study showed that an image with fair gradation could be obtained and that utility of a wide range was expected, although the complete transfer was impossible because the transfer effect was influenced by the materials used, atmospheric conditions and electric characteristics.
The detailed mechanism of the powder image transfer has been still unknown, but this method of roller transfer proved to need lower voltage than a method of corona discharge transfer.

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Photo-dependence of surface potential of evaporated selenium layers has been studied.
Spectral response, transient response and effects of the supperposition of different wave-length illuminations have been measured. Anomalous optical quenching effect other than normal one such as infrared quenching has been found in several selenium layers. In such a layer, surface photovoltage produced by the primary illumination around 600 mμ approaches the dark level on the application of the secondary illumination of the shorter wavelength than about 500 mμ. Such an effect predicts that photo-induced barrier is formed in the selenium layer with the primary illumination, and the barrier is depressed with the secondary illumination.
In this paper, results of the experiment on the anomalous optical quenching is described
and a model for the explanation is proposed.

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