We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
BORAX DEVELOPER CHARACTERISTICS
H. W. MOYSE*
D. R. White*
THIS study of borax developers was undertaken because their wide use emphasized the importance of detailed knowledge of their action. The results of the study not only permit the selection of a developer formula which seems very satisfactory, but also points out the sort of variations that will either increase or decrease the activity of the developer, to meet any special needs that may occur. The tests were made with a number of negative materials in each development. Strips of films were exposed back of a sector wheel which gave a series of exposures, varying on a time scale with a factor of two steps between successive areas of the strip. The strips were then developed for a number of lengths of time in the developer being tested. During this development the flat developing tray used, was rocked systematically to give high, reproducible agitation which, rapidly removed development products from the emulsion surfaces of the strips which were held flat at the bottom of the tray. The densities were read as diffused densities and gave the density-time of exposure — time of development data used in comparing the developers.
To cover systematically the range of possible combinations of chemicals, two series of tests were conducted. In each series, one basic formula was being considered, and the tests centered to some extent on that formula; but in both series, the variations covered a relatively wide range of concentrations. Many of these, of course, were such that they could hardly be of commercial value, but they
Table I
Chemical
Series 1
Series 2
'Range
Sodiiira Sulfite (Anhyd.)
100 g.
75 g.
1—200 g.
Borax
2
5
0 — Saturation
Metol
2
2.5
0—10
Hydroquinone
5
0
0—20
Potassium Bromide.
0
0
0—2.5
Water to
1 liter
1 liter
E^dpath Laboratory, Du Pont-Pathe Film Mfg. Corp., Parlin, N. J.
445