US1597727A

US1597727A - Film

Info

Publication number: US1597727A
Application number: US669552A
Authority: US
Inventors: Sperati Mariano De
Original assignee: IG Farbenindustrie AG
Current assignee: IG Farbenindustrie AG
Priority date: 1922-10-20
Filing date: 1923-10-19
Publication date: 1926-08-31
Anticipated expiration: 1943-08-31

Description

Aug. 31 1926.

M. DESPERATI FILM Filed Oct. 19,

SENJI 77250 L A YER R w A L m a w m m WIT/1 GROUND -L IKE AY CO/WW/V Air/4794147704 6010/?) CELLULOID SUPPORT Lvenfar':

iffarn Patented Aug. 31, 1926.

UNITED STATES PATENT OFFICE.

W0 DE SPEBATI, OF TURIN, ITALY, ASSIGNOB TO I. G. FABBENINDUSTRIE' AKTIENGESELLSCHAFT, 0F FBANKFOBT, GERMANY.

rims.

Application filed October 19, 1923, Serial 1T0, 668,552, and in Italy October 20, 1922.

The present invention relates to filmsfor photographic and motion ictures, and has for its object a film comprising a transparent support, a sensitized layer on one face of said support and a translucent ground layer on the other face of the same support.

Layers or coatings have heretofore been pro osed to prevent halation or curling or ot or to scatter visualv rays in X-ray work; but most of these coatings great inconvenience in handling the ter development, i. e., during printing, and none of them was by any means suitable in pzinting. Various coatings have therefore en devised in the past, which are readily removable, or which may be altered after develo ment in some way to enable printing.

T e present invention relates t a layer or coatin on photographic film which answers not on y'two but three requirements, in that it prevents halation and curling and affords at the same time and without any alteration a suitable ground for retouching.

A film according to the resent invention has a very extensive antialo character in view of the said ground layer which assists efliciently in the absorption of the light passing through its sensitized layer and its support, and the presence of said ground layer prevents the film from rolling or curling in the baths, in the known manner; further the surface of said ground layer is-adapted to receive retouches which may be produced in the most satisfactory manner because they may be erased from said ground surface when incorrect and made up again, said ground layer being not liable to e injured by pencil and soft erasers.

In a preferred embodiment of the present invention a film of the described character comprises a transparent layer which adheres to the support and has crystals or grains of exceedingly'small size embedded in itand which make it translucent with a groundlike surface; a further embodimentcomprises a film having a layer of the described character in which is embedded a substance resent lm afada ted to increase the anti-halo character of t e same In er.

The single represents by way of example and on enlarged scale a sectional view of a film according to the resent invention.

In said sect1on,.1- is a supporting film which is conveniently made of celluloid, as

gure of the annexed drawing conventional, while 2 is a sensitized layer located on one face of said film 1 and which preferably is a layer of gelatin sensitized by means of a silver salt as silver bromidf 3 is a layer located on the other face of the film 1 and which consists of a transparent material adapted to adhere to the celluloid support, as elatin, in which are incorporated exceeding y small grains which cause it to show a ground-like surface and to become translucent. Resins and colloid materials have been found to be particularly useful for this scope.

As stated, said layer may also contain a substance adapted to magnify its antihalo action.

Hereinafter is particularly described by way of example a method of producing a film of the described character.

A solution is prepared as follows:

Parts by I weight. Amyl acetate 120 Acetone 90 Celluloid 1 Another solution is prepared as "follows: Ether 100 c. c., powdered sandarac 12 s., Dammar gum 4. gms., benzene 60 gms.

Then the first solution is added to the second one, the mixture being slowly stirred.

This mixture is spread or distributed on one face of a film and then it is left to dry.

The layer thus produced on the film has embedded in it exceedingly fine and small grains of resinous material and thus it shows'a ground-like surface which is quite adapted to receive retouches made by means of pencil and stumps and permits of eras-' ing the same by means of a soft rubber eraser.

Further said layer is impervious to water and therefore the film may any desired treatment in baths without said layer being apt to become injured or to show stains which would be reproduced on prints made therefrom.

Another example of a mixture adapted to produce a layer of the described character is as follows:

Water 100 c. 0., hard gelatin 8 gms., corn starch 3 gms., phenic acid 0.5 c.'c.-

With this mixture a. similar result as above described is obtained.

An amount of a substance adapted to inbe submitted to p crease the anti-halo action of the said layer may be added to it; say aurantia may be used, an amount of this substance as 10 c. c. of a l solution of aurantia being added to either of the above described mixtures.

Other antihalo substances as red ocher or anilin colors may also be used for the same purpose.

The film according to the present invention may be used for any photographic process and it is particularly useful in producing colour-selected negatives for tri-chromic processes.

What I claim as my invention and desire to secure by United States Letters Patent 1s 2-- 1. A film for photography with visible rays, comprising a transparent support, a sensitized layer on one face of said support, and a layer on the other face of said support; the last-named layer being permanently associated with the support and having a ground-like surface which is capable of receiving retouches. a

2. A film for photography with visible rays, comprising a transparent support, a sensitized layer on one face of said support, and a layer on the other face of said support; the last-named layer being permanently associated with the support and containing small grains which render its surface rough and capable of receiving retouches.

3. A film, comprising a trans arent support, a sensitized layer on one ace of said support, and a layer on the other face of said support; the last-named layer being permanently associated with the support and having a ground-like surface and containing an anti-halo substance, said surface being capable of receiving retouches.

4. A film for photography with visible grains which render its surface rough and capable of receiving retouches.

6. A film for photography with visible rays, comprising a transparent support, a sensitized layer and a permanent layer of gelatin on the other face of said support; the last-named layer having small grains of corn starch embedded in it which render its surface rough and capable of receiving retouches.

7. A film, comprising a transparent support, a sensitized layer on one face of said support, and a permanent layer on the other face of said support; the last-named layer having small grains of corn starch embedded in it to render its surface capable of receiving retouches, and containing an anti-halo substance.

8. A film, comprising a transparent support, a sensitized layer on one face of said support, and a layer on the other face of said support; the last-named layer being permanently associated with the support and having a ground-like surface which renders it capable of receiving retouches, and containing an amout of aurantia.

In testimony whereof I affix my signature.

MARIANO on SPERATI.

on one face of said support,