US2126137A

US2126137A - Color photography structure

Info

Publication number: US2126137A
Application number: US115181A
Authority: US
Inventors: Rowland S Potter
Original assignee: DEFENDER PHOTO SUPPLY Co
Current assignee: DEFENDER PHOTO SUPPLY Co; DEFENDER PHOTO SUPPLY COMPANY Inc
Priority date: 1936-12-10
Filing date: 1936-12-10
Publication date: 1938-08-09
Anticipated expiration: 1955-08-09

Description

Aug. 9, 1938. R. s. POTTER 125,137

' COLOR PHOTOGRAPHY STRUCTURE Filed Dec. 1o, 195e DHEsn/E SqPPoT Cam/00L Wwf? .Sup/20er vBack/NG, L/qn 5ms/rmi .Lm/aes /-SATTORNER Patented Aug. 9, i938 4(liniaal) STATE coLon PHOTOGRAPHY STRUCTURE Rowland S. Potter, Brightfordlieights, NY., as-

signor to Defender Photo Supply Company, Incorporated, Rochester, N. Y., a corporation of New York Application December 1 2 claims.

Thisv invention relates to a color photography structure, and has to do more particularly with a film pack or plate of the type that includes a 1 series of lightsensitive or emulsion layers' which 5 are responsive to different colors and are held in superposed relationship one upon the other during exposure, either with or without ilteringy layers interposed between the light sensitive` layers.

A principal object of the invention is to afford a photographic film pack or plate in which the light sensitive layers are held together closely without any'air space between them during exposure so that sharp and distinct definition of the subject on the negatives is obtained,l and which permits ready separation of the light sensitive layers after exposure so that prints can be made from the several negatives independently of each other.

In a more specific aspect, the invention has for its object to provide a photographic lm pack or plate for color photography in which the several light sensitive layers are united by an adhesive or cementitious substance spread over the adjacent surfaces of the emulsion or light sensitive layers and acting to hold them in close union during exposure. The 'adhesive or cementitious substance is` of a transparent nature and of suchcharacter as to permit pulling apart or otherwise separating the several sensitive layers after exposure, so that they may .be 'printed independnaently, such separation of the layers beingpossi-l ble without resorting to dark `room treatment or delicate handling of the illln.v

To .these and other ends, the invention cons`i'sts in the construction and arrangement that f will appear clearly from the following description when read in conjunction with the accompanying drawing, the novel features being pointed outin the claims following the specification. In the drawing:

Fig. 1 is a sectional view of a photographic illm showing one embodiment of the invention, and

Fig. 2 is a similar view illustrating a modified arrangement where a lter layer is used.

. For a complete understanding of the 'inven' tion, it will be helpful to have a knowledge of the known types of color photography nlm. In one Y form of such film, the several layers sensitive to cement or natural cohesion and may notbe separated. This-.type of construction is suitable only for transparencies, and does notI permit making prints'fromthe negatives. l

In another type `of film, the several emulsion different colors are held together permanently'b'y 0,1936, serial No. 115,131

or light sensitive layers are held superposed one on the other during exposure by Vmechanical pressure, and without the interposition of any cementing material between the layers. This form of construction is open to the objection that close contact betweenv the light sensitive layers cannot be had and a certain amount of air is poeketed between the adjacent surfaces of the light sensitive layers, resulting inlack of clear definition or distinctness of the subject. on the negatives. l

In a third type of film, the light sensitive layers are held together during exposure by cement such ascertain forms of wax, which can be removed to separate the layers after exposure, and before development. To do this, it is necessary to subject the i'llm to heat, solvents, or both, and these operations must be performed in darkness since the lm has not been developed, making the procedure difficult and onewhich has not gone beyond the experimental stage, or proved commercially successful.

According to my invention, the emulsion or light sensitive layers are held together by means that avoids pocketing air between the adjacent surfaces of the layers, while holding them in close contact, and permitting both exposureand development of the several layers as a unit and ready separation thereof after development for independent printing.

One practicalway of accomplishing this consists in the use of a transparent cementitious or adhesive substance such for example as a water solution of soap which is liquid-permeable to allow penetration of the developing liquids to the v several layers and which adheres less tightly than gelatin layers 'adhere to each other, in order to permit subsequent separation ofl the layers, as

nitrate or cellulose acetate, while 2 indicates a gelatin or colloidal backing conventionally used to retain the film in a iiat state.

nate the emulsion or light sensitive layers, respectively sensitive to the primary colors.

1,1 designates i a support or base which can beof cellulose I, l and {desig- 'The light sensitive layer 3 adJacentto the base I is permanently attached thereto, while i designate illms or layers of -cementitious or adhesive substance such as soap arranged between layers land l and between layers 4 and 5. Thus the several layers are held on the base I as a unit and usualillm base is made, also that one or more filter layers may be employed if desired.

In Fig. 2, a structure is illustrated embody-I ing a base 1, gelatin backing 8, emulsion or light sensitive layers 9 III and II, and adhesive or cementitious substance I2. I3 designatesva illtering layer which may be arranged between the emulsion layers and I0 and permanently attached to the latter, acting to permit only red and `green light to come through to the light ,sensitive layers III and Ii, the first layer 9 nearest the lens being sensitive only to blue light. The third light sensitive layer. II- may be sensitive to red and blue only.. where this arrangement is employed, or if desirable, a red filtering layer may be interposed between the light sensitive layers Il and II.

The use of such filter layers is no diiferent from the known practice in the manufacture of color photography film. and where a illter layer is employed, as in Fig. 2, the cementitious or adhive substance Il may be interposed between the outer lightysensitive layer 9 and the adjacent filter layer I3, the latter being `permanently secured to the inner light sensitive layer Il, and the use of the ,gelatin backing, designated at 2 in Fig. 1- and I in Fig. 2. is in accord. with conventional practice and may be omitted, if preferred.

Buch a nlm' or plate can be exposed in the usual manner, and subsequently developed as a unit, the cementitious or adhesive substance such as soap being transparent and liquid-permeable so that the structure may be subjected tothe usual photographic developing solutions which will penetrate all parts of the several light sensitive layers.

After completion of the developing operation,

r the two outer light sensitive layers'can be removed from the remaining layer which is left permanently attached to the base so that the vto the stripping operation.

The outer` layer l or '9 of the film structure is pressed against the separate iilm base referred.

. toand -allowed to dry, after which the outer layer will have adhered to the separate film base to a greater degree than the soap attached sur-- faces adhere to each other. The separate nlm .base can -be stripped or'pulled away and carries with it permanently attached thereto the outer layer s, or s, constituting then an individual' negative which can be printed independently of the others.

By the same procedure, another separate dry gelatin coated base is dipped in a weak solution of gelatin or water, andthe remaining illm unit pressed thereagainst, causing adherence of the second layer 4 or III, which can bepulled laway from the Ithird or 'remaining layer of the illm structure and is permanently attached to its separate film base. The third layer 3 or i I remains attached to its base of the original illm structure, andthe three sensitized layers or negatives are then available for separate printl ing operations.

The character of the adhesive or cementitious substance is such as to permit ready separation of the several layers when' subjected to a stripping operation such as described above, `but it will be understood that other methods of separation than that -described may be employed,

and the essential feature of the invention em- .reference to certain structural embodiments, it

is not confined to the precise disclosures herein,

and this application is intended to cover any Hferent colors, the layers being held together and separated only by an extremely thin stripping layer consisting of a transparentv liquid-permeable adhesive comprising a soap solution which illls the' space and excludes any air between the layers, holding said sensitive layersln optical contact and permitting their development while secured together and subsequent separation for printing independently of each other.

2. A color photography structure comprising a base and a plurality of layers oi material sensitive to diif'erent colors, one of said layers being permanently secured to the base andthe remaining layers being secured to the first layer and to each other by an extremely thin stripping layer consisting of a transparent liquid-permeable adhesive comprising a soap solution that fills the space and excludes any air between the layers and between said base and the adjacent layer. said liquid-permeable adhesive acting to hold said sensitive layers in optical contact and to permit development of the diiferent layers while secured together and separation of the layers after development for printing independentlyof each other. i i ROWLAND B. POTTER.