Author's new simplified method for the sensitometry and grading of photographic papers which was reported recently at the 1965 SPSE Conference (May 17-21, Cleveland, Ohio U.S.A.), is applied for many kinds of domestic papers. Relations to the existing JIS and ASA methods or the formerly proposed DIN method and merits over these methods are discussed and some of the results are summarized in many graphs using these data.

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Eight kinds of merocyanine dyes having almost the same chemical structure, only different in one substituent in each, were synthesized to study the correlations of spectral sensitization with adsorption of dyes to zinc oxide fine crystals in electrophotographic layers.
The merocyanine dyes are 3-substituted 5-[(1-ethyl-4-(1H)-quinolylidene)-ethylidene]-rhodanine derivatives, substituents being hydrogen, ethyl, 2-hydroxyethyl, carboxymethyl, 2-sodium sulfoethyl, 2-diethylaminoethyl, phenyl and p-hydroxyphenyl groups.
Only when a polar, especially an anionic, group is introduced to a dye structure, the dye sensitizes the photoconductivity of a zinc oxide-resin electrophotographic layer, and is adsorbed by zinc oxide markedly. The dye sensitization efficiency is proved proportional to the amount of adsorbed dye.
Comparison of adsorption experiments in the presence of binder resin with those in the absence of it suggests the competitive adsorption between dye and resin.

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