Although a good deal of investigation has been made on the transfer of ink, no quantitative results have yet been available for the factor of rheological properties of the ink which seemed to influence its transferring.
The author studied, using Vandercook proofpress, on the correlation between the viscosity of the ink and its yield value and found that the apparent plastic viscosity determined at the shear rate 150sec^-1 had a good relation with the ink splitting constant f as determined by Zettlemoyer et al.
Moreover it was found that the inkometer value had an interesting correlation with f value, but it should seem that further study is necessary in this respect.

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It is generally believed that color separation depends on a corelation of three factors, the separation filter, sensitive material and light source and as other factors, the condition of developing and succeeding photo-chemical process Influence on the effects.
Since each characteristic of used tungsten lamps for the light source can be drawn by examining their color temperature, to make a fixed condition about the characteristics of color separation filter, sensitive material, and developing process was adopted to define the difference between light sources influencing on separation of negative in changing the kinds of lamp its used condition.
From this experiement the result as following could quoted.
In the color separation to use varied color temperature of one lamp by changing voltage the filter ratio is mostly scaling down and up in the color temperature change, to compare the separating effects in the differences of color-patch the values are within 10% which is not so much as the filter ratio.
As to the effect of kinds of used lamp, no significance could be led on individual.

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The use of the glass crossline halftone screen has been experimentally studied, using test screens with different rulings and ruling ratios. It was found that the screen distance should be shorter than conventional value which is determined in accordance with the screen equation and widely used. Harrison's ideal gradation curve for offset screen negatives with respect to the ideal tone reproduction, which is generally impossible to be attained with normal multiple exposures, is achieved with suitable application of highlight exposure without screen. Screen ruling ratios affect the contrast of screened negatives or their reproducible original density ranges, the sharpness of dots and the required exposure times. With same ruling screens, the thicker the black line is, the lower the contrast of negatives becomes or the larger their reproducible density ranges become. So the screens with thicker black line than the standard 1:1 ratio are advantageously used for screening brilliant original copies with large density ranges, but for the average copy with less range the standard 1:1 ratio screen will work most effectively. Our results above mentioned well agree principally with Rebner's results recently published, but differ in some details. The glass crossline halftone screens can be used with reasonable flexibility and different ruling ratios in most cases will give fairly good results concerning the ideal tone reproduction.
This report of Japanese on the title is one of two instalments, divided by compilation reason, and the rest will be reported as part 2 in the next publication. But English abstract is explaining all about the study.

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