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Volume 62, Issue 1
Displaying 1-9 of 9 articles from this issue
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Nobuaki KAGAWA, Masaki NAKAMURA, Zheliu CHEN, Hiromiti MIZUKAMI, Tomoh ...1999 Volume 62 Issue 1 Pages 2-10
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSA series of new α-fluorinated methine cyanine dyes were prepared, VIS spectra, and redox potential were measured, photographic behaviors were examined, then these dyes were compared with non-substituted cyanine dyes. Fluorinated dyes showed bathochromic shift with 25-30 nm, decreased molecular coefficient and also broadened half-wave length. Fluorination on a-methine position made Ered value of dyes less negative and on the contrary Eox value more negative, and also accelerated the discoloring speed in blix and stabilizing solution, but in contrast, decreased adsorption ability. It was found that new dyes functioned as spectral sensitizer and that resembled their corresponding nonsubstituted dyes in photographic properties.View full abstractDownload PDF (3401K) -
Takanori HIOKI1999 Volume 62 Issue 1 Pages 11-16
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSSupersensitization, especially hole trapping supersensitization, is an important technique in spectral sensitization. In order to obtain a kinetic indication for hole trapping ability of supersensitizers, a method to measure rate constants of a one-electron transfer reaction from a hole trapping supersensitizer to one-electron oxdized cyanine dyes (dye holes) over a pH range of about 2-12 was developed. Then, reorganization energies of the electron transfer reaction were calculated based on a relationship between the rate constants and free energy change of the reaction: the smaller the reorganization energy is, the faster the electron transfer proceeds. Fluorescence quenching experiments on cyanine dyes covalently linked to hole trapping supersensitizers revealed that a supersensitizer moiety with a small reorganization energy efficiently quenched the fluorescence from the cyanine part, in contrast to a supersensitizer moiety with a large reorganization energy which showed no observable quenching.View full abstractDownload PDF (614K) -
Toyohisa OYA, Takanori HIOKI1999 Volume 62 Issue 1 Pages 17-21
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSSynthesis and properties of novel panchromatic desensitizing dyes (1) having an imidazo [4, 5-b] quinoxaline ring and a 9-oxopyrazolo [5, 1-b] quinazoline ring were described. Polarographic analysis indicates that electron-withdrawing groups on the imidazo [4, 5-b] quinoxaline ring stabilize the LUMO level of Dyes (1). Treatment of Dye (1) with OH- in MeCN yielded colorless product (2) via nucleophilic addition of OH- on the methine chain. This reaction was interpreted in terms of the LUMO level.View full abstractDownload PDF (463K) -
The Effect of Coupler HydrophilicityYoshihiko SUDA, Atsushi TOMOTAKE1999 Volume 62 Issue 1 Pages 22-30
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSThe effects of yellow couplers on the developing speed of silver chloride were studied, and couplers having hydrophilic ballasting groups were found to retard the initiation of development. Oil droplets containing such couplers absorbed more color developing agent than did couplers having more hydrophobic ballasting groups. The results suggested that an initial lack of color developing agent in the aqueous gelatin phase of an emulsion caused this retarded initiation of development.View full abstractDownload PDF (1105K) -
New Stabilizing Technique for Image Dyes Using Intramolecular Hydrogen BondHiroshi KITA, Hiroyuki IIZUKA, Koji DAIFUKU1999 Volume 62 Issue 1 Pages 31-37
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSWe prerared a series of new 1H-pyrazolo [5, 1-c]-1, 2, 4-triazole magenta couplers linked to a light stabilizer. We found that the light stability of the CD-3 azomethine dyes derived from these couplers appears to depend on an optimum length of the group linking the coupler nucleus and the stabilizer moiety. A 5-atom-long linking group was most effective in achieving light stability. Molecular dynamic calculation and 1HNMR studies suggested that the sulfonyl group of the light stabilizer moiety and the sulfonamide group (-NHSO2-) of the CD-3 moiety form a macro-cyclic intra-molecular hydrogen bond and the phenyl ling of the light stabilizer moiety is closed to the pyrazolotriazole ling by π electron-π electron interaction in the dye when the number of atoms of the linking group is 4 or 5, which brings the light stabilizer moiety in close proximity to the dye nucleus.View full abstractDownload PDF (4562K) -
Hiroshi KITA, Hirokazu SATO1999 Volume 62 Issue 1 Pages 38-43
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSUsing a stationary phase for HPLC which was modified by a pyrazolotriazole azomethine dye (PT dye), the association enthalpy (-ΔH0) between the PT dye and aminophenol type light stabilizer in an organic solvent (ie., the eluent of HPLC) was measured. It was found that the efficiency of the light stabilizer on light fastness was able to be represented as a function of both the association enthalpy (-ΔH0) and the singlet oxygen quenching rate (log kq) of the light stabilizer.View full abstractDownload PDF (578K) -
Masaru YOSHIKAWA, Hirotomo SASAKI, Shinichi ICHIKAWA, Tetsuro KOJIMA1999 Volume 62 Issue 1 Pages 44-49
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSWe have developed a novel sulfinic acid derivative to stabilize thiosulfate fixing agent, and to minimize replenishment rate at bleach-fix desilvering process.
The substituent effects of benzenesulfinic acid have been studied, and the most effective range of the rate constants (log k2) of the reaction between sulfinates and sulfur has been found to minimize degradation of thiosulfate under a model condition of bleach-fix bath.View full abstractDownload PDF (2142K) -
Hiroyuki KOBAYASHI, Masaya ENDO, Yusuke OKAWA, Takashi OHNO1999 Volume 62 Issue 1 Pages 50-52
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSThe mechanism for the “hydrazine effect” has been proposed by Simson as successive processes started with an oxidation of N'-acyl-N-phenylhydrazines (R-Ph-NHNH-COR') by p-benzoquinone (Q) in PQ-developers to produce N'-acyl-N-phenyldiazenes (R-Ph-N= N-COR'). R-Ph-N=N-COR' is hydrolyzed to produce a strong reducing substance phenyldiazene (R-Ph-N=NH) which makes unexposed silver halides developable by its fogging action. Today this mechanism is generally recognized, but any evidence to support the formation of R-Ph-N=NH has not yet been obtained. In the present paper it was attempted to obtain the evidence using a spectroelectrochemical method. By mixing N-(4-phenylsulfonamidophenyl)-N'-formylhydrazine with Q in H2O/CH3CN (1/1) solution of pH 11.5, a substance which possesses an absorption maximum at 350 nm, was produced. The cyclic voltabsorptogram of this mixture at 350 nm showed that the substance begins to be reduced at ca.-1.1 V vs. Ag/AgCl, the one of the reduction products begins to be oxidized at the same potential, and the other at ca.-0.5 V.View full abstractDownload PDF (410K) -
Hiroshi TABE, Masaroh MOTONAGA, Yasuhiro WADA, Katsumi YAMADA, Hiroshi ...1999 Volume 62 Issue 1 Pages 53-58
Published: February 25, 1999
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSThe reduction process of unexposed AgBr emulsion grains by dimethylamine-borane (DMAB) was investigated in order to elucidate the mechanism of the formation and growth of fog nuclei. The TEM photographs of the mono grain layer of an unexposed AgBr emulsion treated with the alkali solution of DMAB showed that a number of silver micro-clusters was formed on the crystal surface randomly and grown to massive silver particles. The anodic oxidation of DMAB at a silver electrode was strongly suppressed by gelatin. It was suggested that the non-selective reduction process of AgBr emulsion grains by DMAB did not proceed via the autocatalytic reduction at the clusters but the redox reaction of DMAB with silver ions followed by the aggregation of silver atoms to the clusters.View full abstractDownload PDF (5330K)
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