US2267089A - Color photography - Google Patents

Description

Patented Dec. 23, 1941 2,267,089 Y coma PHOTOGRAPHY John Eggert, Leipzig, and Gerd Heymer, Wolfen, Germany, assignors, by mesne assignments, to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware Application Dec rn l a Claims.

The present invention relates to the production ci photographic multi-color pictures.

Une of its objects is a photographic material producing multi-color' component images. An-

ember 2, 1938, Serial No. 113,827 n3 :L l Dccmbef 7,

component color picture has been in thismanner preserved the first developed layer is mechanically or chemically removed' and then the underlying layer is developed after the hitherto other object is a process of producing multi-color 5 separating layer has been made permeable in a component images. Further objects will be seen from the detailed specification `following hereafter.

In the production of three-color components for color photography it has been proposed in U.S.Patent 2,210,146 of which the present application is a continuation in part to insert between superimposed emulsion layers intermediate layers which withstand certain kinds of developers and treating baths but are permeable by others or which can be made permeable by treatment, for instance by saponiflcation.

This device of using variable intermediate layers may be used for the production of a new kind separate bath or simultaneously in the developing operation. This component picture produced in the second layer is printed in the manner described above to produce the second color component picture or is used directly. In case of a bil5 layers there must be also used for the development ofthe second component picture a developer which does not attack the separating layer lying between the second and the third emulsion layers. Fromthe second component picture in such a of exposure material which, in the technique of three-layer iilm there is made a copy on an auxilexposure does not diier from the simplicity of the known bi-pack but yields, however, threecolor. components in a simple manner. This invention consists in a process which uses, in its simplest form, two lms, layer to layer travelling through the camera, of which lms one carries a single emulsion layer and the other two superimposed emulsion layers, the latter being sepa'- rated by an intermediate layer of the above kind which may also serve as a filter layer. Instead of two lms a single one maybe used which carries three superimposed layers, each separated from the other by an intermediate-layer of the above kind, which, if desired, may also serve as iilter layers.

The essence of the invention resides in the fact that individual layers are treated in such a manner that it is possible to obtain separately the component color pictures from the material. Two courses are possible. In the iirst, after exposure, which may occur in an ordinary cinematograph camera, iirst the top layer oi the two or three superimposed layers is developed in a developer which leaves unaffected the under-lying intermediate layer and in consequence also the emulsion layers under-lying that intermediateY A Then, if desired, after drying the layer. the blackand-white image in the upper layer is copied on an auxiliary illm by means oi' light of a color for which the still undeveloped layer or layers of the nlm is or arev not sensitive. Alter this first 86 and is protected from the access of false light in The second course for obtaining. the component pictures separates thecomponents produced in the several layers, not by successive copyings but by the diierence'in their spectral properties. In this `procedure one may, for instance, tone the top layer after the development or one may develop 'by means of a developer which immediately or after separation of the sil- .30- ver image yields a color picture by the process of color development or by the silver anti-diazotate process. Then, in the manner described above,

the intermediate layer-is made permeable. The

under-lying layer is developed and toned in another color. 'I'his coloringneed not have any 40 copy are to be obtained.

The following example 'when taken with the accompanying self-explanatory drawing, Fig. 1 of which shows a bi-pack raw iilm -and Fig. 2 of which depicts the processing thereof, illustrates the invention:

A bi-pack is used in which the 'front illm carries two layers separated by an intermediate layer which isimpermeable to an acid developer. The layer next to the illm is sensitive only to blue light, the superimposed layer is sensitive to green light and is protected from the eilect of blue rays by a yellow coloring of the whole layer or by a yellow coloring oi the intermediate layer. The rear iiim is a panchromatic or red-sensitive illm known manner by a red iilter layer. ,Moreover, it is preferable to provide anti-halation by a nonactinic coloring of the film support. The ex posure in the camera is as usual, the layers being towards each other. After the exposure `-the rear nlm is developed in the usual manner; the front lm is developed by an acid developer, for instance bythe known ferrous oxalate developer wherebyA a picture is produced only in the top layer. After development the image is ilxed. However, this iixing mayV -be omitted without auectlng the process,

The green component thus produced in the top layer is now copied with the v aid of light lackingblue on an intermediate iilm sensitive to green or red light, whereby a positive or if ldesired a reversal negative is obtained which may be used as the second of the components for producing a color picture. The original negative in the top layer is removed .with the aid ci hot water mechanically or`by means of a solvent for silver' chemically. Then follows the development of the -second blue-sensitive layer with the aid of an developers,.the lower is permeable only for acid developers. First the upper emulsion layer is developed by means of the ferrous oxalate developer which does not penetrate the firstV separating layer and the intermediate positive is obtained, then. this separating layer is made permeable by an alkaline intermediate bath or the second emulsion layer is developed in an alkaf line developer which cannot penetrate the second separating layen Finally the acid developer is 'again used, whereby the second separating layer i. A process of producing photographicl color component pictures which comprises exposing a 'b1-pack consisting of a single layer rear illm and of-ga front nlm carrying two differently optically sensitizedsilver halide emulsion layers separated by anfintermediate layer which is impermeable4 for certain developers, developing the upper layer`oi'thefront film with adeveloper to which the intermediate layer is not permeable, copying the developed silver imge by means of light which is non-actinic to the still undeveloped layer, removing the upper layer, treating the intermediate layer in a medium which renders it permeable to the following developer; developing the lower layer -and printingthedeveloped silver image.

2. A process oi producing photographic color component pictures which comprises exposing a bi-pack consisting of a single layer rear nlm and ot a front iilm carrying two diiierently optically -sensitized silver halide emulsion layers separated by an intermediate layer which is impermeable termediate layer is permeable and printing the developed silver image.

3. A process of producing photographic color component pictures, which comprises exposing a multi-layer lm. the single silver halide emulsion layers of which are diierently optically sensitized and separated by intermediate layers impermeable for certain developers, in such a manner that each sin'gle emulsion layer obtainsa component image, developing the uppermost emulsion layer with a developer .which isunable to penetrate the `is made permeable and the third emulsionY layer .o developed.

underlying intermediate layer, printing the silver image of said developed layer on a suitable photographic material, removing the uppermost emulsion layer, making permeable the intermediate layer and developing the second emulsion. layer, and repeating the same operations for the following layers.

.4. A process of producing photographic col'or component pictures, which comprises exposing a multi-layer lm, the single silver halide emulsion layers of which are differently optically sensitized and separated by intermediate layers impermeable to certain developers, in such a manner that each single emulsion` layer obtains a component image, developing the uppermost emulsion layer with a developer which is unable vto penetrate the underlying intermediate layer,

printing the silver image of said ldeveloped layer on'a suitable photographic material, removing `the silver image, making permeable said intermediate layer, developing the second emulsion layer and repeating the same operations for the`

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