US1166540A - Sensitized film for process printing. - Google Patents

Description

L. A. ORANS.

SENSITIZED FILM FOR PROCESS PRINTING.

APPLICATION FILED MA Y 20, I914.

Patented Jan. 4, 1916.

M M W N I WITNESSES:

ATTORNEY making LOUIS A. ORANS, OF NEW YORK, N. Y.

Specification of Letters Patent.

Patented Jan. 4, 1916.

Application filed May 20, 1914. Serial No. 839,855.

To all whomit may concern: Be it known that I, LOUIS A. ORANS, a citizen of the United States, and a resident of the city of New York, in of New York and State of New York, have invented certain new and useful Improvements in sensitized Films for Process Printing, of which the following is a specification.

This invention relates to the sensitized medium used in process printing to obtain the photographic negative which is used for the photographic reproduction upon the printing plate.

In photo-mechanical process printing, whether relief. litho or intaglio,'=the usual procedure has been to make a screened negative of the subject to bereproduced, from which a positive is inad'ellidirectly upon the printing plate. In case of color. reproduction, several positives must be made upon 4 as many plates according toithe number of a negative through a eolor iiitler,

able work has to be done up'on the sprinting plate itself in rections directly upon a job is proved up,

colors desired, either from the same negative or from a number of negatives taken through color filters. Inanyevent, whether the printing plate is for black and white only, or whether it be for color printing from an ordinary screen negative or from considerorder to get proper tone values. Thus, in case of a relief printing plate, the artist has to go over every part of the .plate to correct the tonal qualities by etching deeper, or routing away the lighter tones and the high lights and burnishing the shadow portions. This process is laborious and requires the work of specially skilled etch artists who are compelled to work with a hard substance forming the material of the printing plate. Thus, after it goes back to the artist and he has to criticise the plates for corrections in the tonal qualities and the plate then has to be again gone over by the etcher. The present invention has for its object to obviate the necessity of making the corthe printing plate and to enable the artist to make the necessary changes directly upon thescreen negative, much more expeditiously and easily than can be'done upon the printing' plate.

carrying out the invention, I employ a photographic film having a base consisting of a soft buttough body such as celluloid the county qualities a series of dots, stipple work,

them entirely and causing tive print lighter, the same may or the like, upon the surface of which are formed projecting ridges, such as dots, grains, mechanical stipple, or the like. This undulatory or serrated surface is sensitized by a suitable sensitizer and treated as an ordinary dry plate to prepare the same for use in photographic exposure, usual screen. After the plate has been exposed and the negative developed, the tonal of the latter may be strengthened wherever desired by abrading the crests of the projections.

In the accompanying drawing illustrating the improved film, Figure 1 is a planview of the film, and Fig. 2 is an enlarged sectional view illustrating the' projections formed on the, surface of the film. Fig. 3 is an enlarged sectional view illustrating the profile of the corrected negative obtained from the improved film, Fig. 4 is a view of the back of the film showing a scale according to which the film may be shifted angularly.

Referring in detail to the drawing, the film consists of a base 10 having embossed, cut, cast, etched, upon the surface thereof, projections 11. This film or plate-is exposedthrough" a Levy .screen or any other form of screen or mezzotint to reproduce the subject in like.

. After the negative'is developed and the artist desires to make parts of the same print darker, allhe has'to do is to scrape away the crests of the projections, together with the opaque coating formed by the -fixed sensitizer, by means of asharpened instrument or other abrading means such cloth or-the like. Thus, in Fig.- 3; it will be noted that the crests 13 of the projections ll have been scraped away, leaving a trans "'lucent surface on the top of each pro ection, which, of course, will .print black upon the positive. If it'is desired to make the negative still darker, the projections can be cut down farther to the point of removing that portion of the negative to print solid. On the other hand, should it be desired to make the negabe painted with some opaque adhesive paint, as'will be readily understood. I prefer to use with the negative in cases where the film has projections on it in the or otherwise produced through the grains or the v as emery will-be seen that the film itself should be shifted, for each color as'well as the'Levy screen. The film may have therefore impressed or otherwise indicated thereon, (Fig. 4) a circle or are bearing'division marks in degrees from which the angle of shiftof the film may be determined.

. lit [will be clear that my improved film not only can be usedin thejordinary process camera,- but areproduction can be made upon it by photographicallylgi'nting thereon from a'zpQiSltlVe made from a negative upon which t eimage has been printed through a'Levy or tther screen.

I have described the negative plate as being in the form of afilm. It may'be underprovided.

stood, however, that instead of a film, a glass late may be used upon which a soft, tough coating with suitable surface pro ect1ons is It willthus be seen that I have provided anew photographic film or plate for screened negatives upon-which the necessary correcv tions may be directly made' with a minimum of labor and expense. It will be noted also ing printing plates whereby all corrections corps of trained men in a printing establish;-

may be made directly upon. the negative inment may be dispensed with and their work 'accompli'shed as effectually by theartist. I

' topics of this patent may be obtained for Having thus described my invention, I

messes claim as new and desire to secure by Let ters Patent:

,1. A dry photographic film. consisting of a base of substantially transparent material havingprojections'upon the surface thereof.-

and a sensitizing coating on said surface.

2. A dry photographic film having a base of soft comparatively tough material which is sufiiciently transparent for purposes of printing, said base having projections on the surface thereof, the crests of which projections are abradable to form 'a grain of varying density and a sensitized coating on said surface. 7

3. A photographic filmcomprising a base of material which is sufiiciently transparent for purposes of printing, said base having projections on the surface thereof corre sponding to the dots on a Levy screen, and

a sensitized coating on said-surface.v

4:. A dry photographic film consisting of a base of translucent material having projections upon the surface thereof and a sensitizlng coating on said surface, and an arc with angular. divisions on it impressed thereon.

5. A dry photographic film consisting of a base of abradable material sufliciently transparentfor purposes of printing, said base having projections formed on the surface "thereof to form a grain suitable for photo .that I have devised anew process of correct I Witnesses:

mechanical printing, and a sensitized coating on said surface.

@Signed at New Yorkcity, in the county of New York and State of New York, this l8t h.day pf May A. D. 1914:. r

LAZARUS Burr, DAVID ORANS.

five cents each, by addressing the Commissioner oi? Edtento, V Washington, 1'5. Go!

LOUIS. A. DEANS. V

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