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The action of fatty acids on cellulose
NOTES FROM THE RESEARCH LABORATORY, EASTMAN KODAK COMPANY.* EFFECT OF E N V I R O N M E N T ON PHOTOGRAPHIC SENSITIVITY. II. EFFECT ON CERTAIN SALTS. 1 S. E. Sheppard and E. P. Wightman.
THE action of certain neutral salts on the formation of the latent image has been studied. Potassium citrate had no detectable effect, potassium chloride a slight effect upon developability, potassium bromide a very considerable depressing effect on the formation of the latent image. Contrary to the behavior with the visible image, acid silver nitrate was not found to accelerate latent image formation, at any rate with fairly high speed plates. The results are discussed in terms of the transfer of electrons from bromide ions to silver ions of the lattice, and it is suggested t h a t the electrostatic field of the adsorbed double layer is a modifying factor of differing importance for visible and latent image formation.
THE ACTION OF FATTY ACIDS ON CELLULOSE? C. J. Maim and H. T. Clarke.
WHEN native cellulose is boiled with a lower fatty acid, esterification takes place which tends to a limit expressed by the formula: C24H390~0(CO.R). W h e n hydrated or mercerized cellulose is treated in the same way, the limit is CaH90~(CO.R). From this it is concluded that the constitution of cellulose m u s t be expressed as a multiple of the unit C24H.~90_~0. * Communicated by the Director. Communication No. 349 from the Kodak Research Laboratories and published in Phot. J., 69: 22. I929. 2 Communication No. 367 from the Kodak Research Laboratories and published in J. Amer. Chem. Soc. 5I: 274. I929.
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THE action of certain neutral salts on the formation of the latent image has been studied. Potassium citrate had no detectable effect, potassium chloride a slight effect upon developability, potassium bromide a very considerable depressing effect on the formation of the latent image. Contrary to the behavior with the visible image, acid silver nitrate was not found to accelerate latent image formation, at any rate with fairly high speed plates. The results are discussed in terms of the transfer of electrons from bromide ions to silver ions of the lattice, and it is suggested t h a t the electrostatic field of the adsorbed double layer is a modifying factor of differing importance for visible and latent image formation.
THE ACTION OF FATTY ACIDS ON CELLULOSE? C. J. Maim and H. T. Clarke.
WHEN native cellulose is boiled with a lower fatty acid, esterification takes place which tends to a limit expressed by the formula: C24H390~0(CO.R). W h e n hydrated or mercerized cellulose is treated in the same way, the limit is CaH90~(CO.R). From this it is concluded that the constitution of cellulose m u s t be expressed as a multiple of the unit C24H.~90_~0. * Communicated by the Director. Communication No. 349 from the Kodak Research Laboratories and published in Phot. J., 69: 22. I929. 2 Communication No. 367 from the Kodak Research Laboratories and published in J. Amer. Chem. Soc. 5I: 274. I929.
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