DE1038915B - Process for the production of duplicate copies after transparent multicolor images by a two-step copying process over an intermediate copy - Google Patents

Description

It is known to duplicate multicolor transparent images by applying a two-time copying process over an intermediate copy. With this simplest method, based on a positive image, one initially obtains a Negative and from this in turn a positive image, while, starting from a negative image, initially receives a positive and then a negative image. If you use for the production of the Intermediate negative or positive and: the final Bild Multilayer color films with the usual complementary assignment of layer sensitivity and sub-picture color, i.e. blue-yellow, green-purple, Red — blue-green, as is well known, finds a considerable Deterioration in color rendering takes place. This is due to the fact that the absorption of the chromogenic development obtained image dyes, especially the magenta dye, from the theoretical Requirement differs and therefore a color shift occurs with each copying process, which in first and foremost a strong desaturation of the yellow hues with a simultaneous blackening of the causes blue hues. In the double copying process, these color shifts increase, so that a dupnegative film produced in this way from a colored motion picture negative film does not show any in provides screening films comparable to the color quality of the copy of the original negative. Likewise gives way a duplicate copy produced in this way from a positive color slide image will differ considerably from the original. One has therefore z. B. doweled negative films on the way over three black and white partial color separations. However, this method is very cumbersome in terms of process. If you want the easy way of going twice Copying process, then you have to achieve a portable color reproduction, so-called color masks apply, with the color mask either applied to separate material, which in turn the process complicated, or where the color masks in a known manner in the multilayer material can be developed by yourself. However, the use of such color masks is inevitable Complications associated with the workmanship or manufacture of the materials. In addition, you have to in the production of the intermediate negative or positive for duplicating a positive or for duplicating a negative without a mask and the final copy two different materials, viz use one masked and one unmasked, which in turn complicates processing.

It is also known that the presence of colored couplers, which act as a filter during exposure, leads to certain errors.

for making duplicate copies

for transparent multicolor images

by copying twice

via an intermediate copy

Applicant:

Agfa Aktiengesellschaft,

Leverkusen-Bayerwerk,

Kaiser Wilhelm Allee

Dr. Ottmar Wahl, Opladen,

and Dr. Erich Böekly, Cologne-Stammheim,

have been named as (inventors

It has now been found that transparent multicolor images produce duplicate copies of good color reproduction using a duplicate process when going to both manufacture the intermediate copy as well as the final copy a multi-layer color film with colorless couplers used for chromogenic development in which, deviating from the usual complementary Assignment of layer sensitivity and partial image color to the emulsion layer for the yellow partial image sensitive to green and the emulsion layer for the purple image is sensitive to blue, as it is in itself in known in color photography. For the production of the intermediate negative or the intermediate positive and the final copy is, for example, a multilayer color film with incorporated colorless Components suitable that have a red-sensitive silver halide emulsion for the blue-green partial image, above a green-sensitive layer for the yellow partial image and a blue-sensitive layer Wear layer for the purple part image. You can still use a multilayer material where the blue-sensitive layer for the magenta image lies over a yellow filter layer, with the others both layers below can be arranged in any order. So can the green-sensitive Layer for the yellow image as the middle layer and

& 09 637/425

the red-sensitive layer for the blue-green image is present as the bottom layer, or these two layers can be exchanged.
• For the blue-sensitive purple layer, an emulsion consisting of bromide silver or bromide iodide can be used, while the other two layers can consist of chlorine silver or predominantly chlorine silver. In this case, the three layers can be arranged in any order.

That the assignment of layer sensitivity and partial image color deviates from the usual complementary assignment can change is known per se, with purely theoretically a large number of Variants is possible. It was not foreseeable, however, that the special type of assignment of Layer sensitivity and partial image color according to the invention, in particular in connection with the Duplication or duplication process, a surprising technically valuable one via an intermediate copy Effect. This effect is that the colors of the original are far better in the copy are reproduced, as in the case of using a multilayer material with the usual complementary Assignment.

A dupnegative produced in the claimed manner from a negative motion picture e.g. B. provides positive copies, the opposite of the copy from the original negative no longer show whitening of the yellow tones. Likewise are those made in this way Copies of positive color slide images of better color quality than those made using film produced with orthodox assignment. The advantage over the known method using black and white extracts is the considerably easier processing, the advantage over the color mask process likewise the simpler processing or manufacture as well as the possibility of processing only a film material for the intermediate image and the final image.

The structure of a multilayer material that is suitable for the method described here, is illustrated in Fig. 1 a and 1 b for example. In the figures, 1 denotes a blue-sensitive silver halide emulsion layer made of predominantly bromide silver with a color component for the purple image, 2 a yellow filter layer, for example made of colloidal Silver, 3 a green-sensitive halogen silver layer made predominantly of bromine silver with a color coupler for the yellow partial image, 4 a red-sensitive halogen silver layer from predominantly bromide silver with a color coupler for the blue-green part of the picture and 5 den transparent substrate.

Furthermore, in the case of a multilayer material without a yellow filter layer, a layer arrangement can be selected as shown for example in Figs. 2a and 2b, wherein 1 sensitized one to green light Chlorosilver emulsion with a coupler for the yellow partial image, 2 one sensitized for red light Chlorosilver emulsion with a coupler for the blue-green partial image, 3 an unsensitized bromosilver or. Silver bromide emulsion with a coupler for the purple image and 4 a transparent support means.

In addition to the layers mentioned, the films can also be used for the construction of multi-layer color films have conventional auxiliary layers, for example protective, separating, filter and antihalation layers.

The gradations of the individual layers for the partial images are matched to one another or to specific developing baths using the usual color developer substances so that a neutral gray step wedge can in turn be reproduced in a neutral gray and with the same gradation (y = 1).

example

A motion picture negative film is copied in contact onto a multilayer film, the structure of which is above was specified. The color development leads to an intermediate positive film, the color of which is not corresponds to the color of the subject. The contact copy of this intermediate positive on the same film material and the color development then leads to a duplicate negative, its color quality largely corresponds to that of the original negative. You can make full-fledged copies of this duplicate negative draw.

If, instead of the multi-layer material, according to the invention, a multi-layer color film is used with the complementary assignment of layer sensitivity and partial image color, for example one Film with a red-sensitive layer for the blue-green part of the image starting from the base a green-sensitive layer for the purple part image, a yellow filter layer, and a blue-sensitive layer If the layer for the yellow partial image bears, a dupnegative is obtained, the color quality of which is opposite the original negative is significantly worse. The copies made from this dupnegative have, based on the same gray reproduction, only very whitish yellow tones and on the other hand heavily blackened tones and can only be used to a very limited extent.

A negative film with a yellow mask can be dowelled with good success using the former method become a worthless dup film during the second-mentioned process because of the loss of yellow tones leads.

Claims (4)

Patent claims: 1. Process for the production of duplicate copies after transparent multicolor images by a two-time copying process via an intermediate copy, characterized in that for the Making the intermediate copy and the final copy a multi-layer color film with embedded colorless components are used for chromogenic development, and a green-sensitive silver halide emulsion is used for the yellow Contains partial image and a blue-sensitive silver halide emulsion for the purple image. 2. The method according to claim 1, characterized in that that the multilayer color film for the intermediate copy and the final copy is one red-sensitive halogen silver emulsion layer for the blue-green partial image, a green-sensitive one for carries the yellow partial image and a blue-sensitive one for the purple partial image. 3. The method according to claim 1, characterized in that for the intermediate copy and for the The final copy uses a multilayer color film with the blue-sensitive purple layer over a yellow filter layer and the other two layers in any order are arranged underneath. 4. The method of claim 1, wherein the blue-sensitive magenta layer consists of a predominantly There is an emulsion containing bromine or bromide iodide, while the other two layers consist of chlorine silver or predominantly chlorine silver, with the three layers in any Order can be arranged. Considered publications:
Article by W. Schneider: The "color photography" in European study folders, 1944, p. 22ff., Published by the Academic Cultural Exchange. 1 sheet of drawings