DE605235C - Process for the gradation adjustment of partial color negatives obtained by means of superimposed emulsion layers with different silver content - Google Patents

Description

Process for the gradation adjustment of by means of superimposed Emulsion layers of different silver content obtained partial color negative for the production of natural colored designs. visible or transparent signs are required as is well known, partial negatives, which are achieved by usually using the original three times, each time using a different color filter (red, blue, green) upstream. Naturally, these three or four negatives must match, otherwise colored double contours would arise. Usually it is very difficult to go through consecutive Exposure of the three exposures to obtain covering partial negatives. The slightest movement of the object to be recorded results in unusable partial negatives; were well Devices created that allow the partial recordings very quickly one after the other to be able to expose, but these also fail with moving objects.

Absolutely opaque partial negatives can only be obtained if these are exposed at the same time.

By exposing three superimposed layers that Receiving partial negatives is a well-known way; are similar arrangements also known, but these only refer to the different versions. So were z. B. used two glass plates coated with emulsion, between which there is an emulsified film. Also has already been. made the suggestion to use a glass plate with two emulsified films, their top layer can only be removed after drying.

In order to avoid light scattering in the case of these through-exposure of layers lying one on top of the other to avoid which the image sharpness of the backward emulsion layers is extraordinary It has been suggested that the front two emulsion layers are affected by it to make great silver poverty and thin casting of the layer as transparent as possible. Since with increasing lack of silver and thinness of the emulsion layer, so does the opacity of the silver negative achieved with it decreases rapidly, so that this also with the usual Amplifiers can no longer be made copier, so was still a Reinforcement of these thin silver negatives by converting them into dye stain images suggested. However, this allows a much stronger gain achieve, which, however, are very narrow limits that with increasing The lack of silver and the thinness of the layers also led to an increasing flattening of the gradation Goes hand in hand, which then no longer matches that of the other partial color negatives; just as it requires the achievement of color-correct three-color prints. It is now that Essence of the present proceedings, this deficiency by a special type and choice to fix the coloring.

In order to create this gradation compensation, according to the invention the Silver picture in one Transformed stain, e.g. B. iodized silver or copper = rhodanür and with. stained with such a basic red dye, which is found in the Thin yellowish, in the density appears red in transparency. Such is z. B. Safranine yellowish. It is even better to combine a red dye with a yellow, e.g. B. Thioflavin yellow to combine. The colored stain picture then has the thinnest Make a yellowish, in the densest areas a red appearance, which through the different actinic color - from yellow to red in the copying process - a gradation compensation is achieved. You can now. Dye with lacquer-forming bodies, e.g. B. one Fix the solution of sulphurized phenols in the manner of commercially available Katanol and the pickling body (iodized silver, copper rhodanur) with. Black sulfur sodium. These The type of reinforcement is sufficient to cover the otherwise unusable foremost silver negative to turn it into a usable negative. Even shorter exposure times achieved one by doing the second, d. H. middle emulsion layer also low in silver applies and retrospectively through a less intensive reinforcement of this kind treats that a harmony of the three partial negatives is achieved, e.g. B. by that one transforms the second partial negative like the first into a stain picture ", and in the In contrast to the first one - not staining with red, but only with yellow dye, whereby the stain can also be blackened afterwards.

One embodiment is e.g. the following: On .one on a carrier The red-sensitized emulsion that is present becomes one on a thin support located green-sensitized emulsion layer on layer placed on this the blue-sensitive one with yellow screen dye, on one. thin Carrier located emulsion placed in such a way that the layer side of this emulsion comes to lie on the support of the second green-sensitized layer. The foremost, blue-sensitive layer is cast so low in silver that it appears almost transparent, the second layer is also very low in silver, while the third layer is one represents normal emulsion. After exposure, the three layers are developed and fixed. The silver image of the first and second layer is made in a known manner in a shared bath in a stain, e.g. B. Kupferrhodanür or Kupferjodür transferred; The first picture with the lowest silver content in a dye bath of safranine is yellowish, the second Silver negative in a pure yellow dye bath (thioflavin or chrysoidin) yellow stained. Both colored silver pictures are put together in a bath of sodium sulphide bathed with the addition of Katanol, whereby the dye fixes, the stain in a dark sulfur compound is transferred.

Claims (1)

PATENT CLAIMS: e.g. Procedure for the gradation adjustment of means superimposed emulsion layers of different silver content obtained Partial color negatives by converting the. Negatives in color stain pictures, thereby characterized in that for coloring the differently graduated negatives from one another different dyes or dye mixtures are used, which per se well-known property that their absorption capacity - for short-wave (actinic) With increasing dye density, light grows faster than its total absorption capacity, in varying degrees (e.g. Safranin. -j- Thioflavin yellow for the silver poorest, Chrysoidin - or thioflaviri yellow alone for the silver-rich layer): -2. procedure according to claim i, characterized in that after the development, the fixing and coloring the front and back emulsions sends the colored pictures In order to achieve an even greater reinforcement, if necessary together in a bathroom brings, -which fixes the- "dye insoluble and at the same time the pickling body transformed into a dark compound (e.g. a solution of sodium sulphide with Addition of sulphurous phenols in the manner of the commercially available Ka.tanol).