All issues
Volume 32, Issue 2
Displaying 1-8 of 8 articles from this issue
- |<
- <
- 1
- >
- >|
-
Toshibumi SAKATA1969 Volume 32 Issue 2 Pages 51-56
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSIt is described that the present situation and the problem of new imaging system in the Photography, Printing, Communication and others has many possibilities.
Researchers of these new fields in Japan increased in many Institutes and Industries during few years. The requirement and the basic principle of new imaging systems considered by the optical image evalution and the system engineering, and also future plan have discussed from the stand point of Imaging Science and Engineering.View full abstractDownload PDF (888K) -
Rokuhiko NAKAJIMA, Kojiro KINOSHITA1969 Volume 32 Issue 2 Pages 57-67
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSBy using random-charts with distribution functions of Uniform type, Normal type and Beta types, relations between the distribution functions and legible thresholds of Japanese letters were investigated.
The Uniform type random-chart in checker-board was made of random sampling numbers with uniform distribution. The Normal type random-chart and Beta type random-charts in four bits were constituted from random sampling numbers with normal and beta distributions, respectively. The legible thresholds were defined that 80 percent reactors were able to read Japanese letters, as certain rad-lux ratio of these letters to those random-charts were given.
In consequent of the experiments, order from the higher illegibility to the lower one became of Beta II (p=2.0, q=0.5: parameters of beta function) distribution type, Normal distribution type, Beta I (p=0.5, q=0.5) distribution type and Uniform distribution type. The above conclusion, that is the Uniform distribution type gave the lower effect of illegibility, supports that graininess on halftone etching is better than other printing processes.View full abstractDownload PDF (7523K) -
On the Formation of Fog Centers in Primitive Silver Bromide Emulsion GrainsTakekimi SHIOZAWA1969 Volume 32 Issue 2 Pages 68-74
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSThe fog centers on primitive silver bromide emulsion grains (mainly tabular) which have not been exposed to light were ovserved by electlon microscope and analysed some proparties of these centers.
The dispersity, size or location of the fog centers produced by the surface-developer depends on the concentration of developing agent; in the development by glycine-carbonate surface-developer of Stevens' original formula, numerous fog centers were produced.
These centers were formed preferentially on the central region of flat surface of large grains. These centers were not observed to grow in size, but instead many new fog centers weregradually formed during prolonged developing.
In the development by a diluted surface-developer solution, a few fog centers were formed. Preferred formation of these centers on the central region of grain surface was not observed in this case. Prolonged development caused the growth of these fog centers, which resulted in filamentary form. This is contrary to the case with the above-mentioned concentrated developer (Stevens' original formula).View full abstractDownload PDF (16086K) -
Shinya MIZUSAWA1969 Volume 32 Issue 2 Pages 75-81
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSPotentiometric titration method, by means of potassium ferricyanide as titrant and recording auto-titrator, was applied to the determination of Phenidone in photographic P.Q. developers. In acidic solution, potassium ferricyanide selectively oxidizes Phenidone without oxiding hydroquinone and sodium sulfite. Therefore, the separation of Phenidone from the other ingredients of developer by extraction, that has been needed in conventional methods, is unnecessary. The reaction is not very rapid, but thesharp potential jump in titration curve was obtained in 2N-sulf uric acid.View full abstractDownload PDF (815K) -
Minoru TSUDA1969 Volume 32 Issue 2 Pages 82-86
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSStudies were made on the photochemical and dark reactions of poly (vinyl cinnamate). The results obtained were as follows:
1. The phtochemical reaction of poly (vinyl cinnamate) is a one step reaction forming four-membered ring. This reaction scarecely occurs thermally because of the high activation energy in the reaction path although it occurs adiabatically in the photochemical process.
2. The four-memberd ring formed photochemically is stable for heating, but easily goes back to the cinnamoyl groups photochemically.
3. In the four electrons system formed by two cinnamoyl groups, an excitation of one electron leads to the formation of a four-membered ring.
4. It is considered that the dark reaction of poly (vinyl cinnamate) is a multi-stage radical reaction following the formation of a free radical.View full abstractDownload PDF (596K) -
Discussion on the Lith EffectTsuneo SUGA1969 Volume 32 Issue 2 Pages 87-94
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSThe lith developer is alkaline hydroquinone developer having very low concentration of free sulfite ion. When the lith type emulsion is treated in lith developer, it has a very short toe and can be developed to a very high gamma. Yule considered that the oxidation products of hydroquinone act as accelerators for lith development. James considered the oxidation of latent image by quinone.
This paper relates to the effect of bromide ion and quinone in lith developer and the mechanism of lith development.
The experiments showed;
1. When commercial lithfilms were developed in the sulfite free hydroquinone developer containing no bromide ion, the lith effect disappeared completely.
2. Among the substances whose silver salts are difficult to solve, bromide ion showed a large lith effect and thiocyanate ion showed a little lith effect.
3. The oxydation of latent image by quinone was promoted by bromide ion and at lower pH. That of metallic silver was promoted by iodide ion, bromide ion and thiocyanate ion.
4. When exposed lithfilms were immersed in oxidizing solution containing quinone and bromide ion before lithdevelopment, they showed short toe.
Redox potential of latent image seems to be about 0.1-0.2 V more negative than the potential of metallic silver.
In the presence of bromide ion the possibility of oxidation of latent image is considered.
It is presumed that good lith effect may be obtainable by balancing both of accelerating effect in the higher-exposure regions and of oxidizing effect in the lower-exposure regions.View full abstractDownload PDF (877K) -
[in Japanese]1969 Volume 32 Issue 2 Pages 95-104
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSDownload PDF (1200K) -
1969 Volume 32 Issue 2 Pages plate1
Published: June 25, 1969
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSDownload PDF (3227K)
- |<
- <
- 1
- >
- >|