US1668686A - Method of reproducing pictures and the like - Google Patents

Description

Patented May 8, 1928.

UNITED "sTATEs PATENT OFFICE.

remix 1). LIvEnMonE, or ran noomwav, NEW YO K, AssIeNoa, BY manor m unsnn ASSIGNMENTS, ro SCREENLESS ooLonroNE oonrona'rron, A ooarom- TION OF NEW YORK.

METHOD OF BEPRODUCING PICTURES AND THE LIKE.

Io Drawing.

My invention relates to an im roved method of reproducing on paper, car board or other sheets of stock, photographs, copies of paintings, drawings or illustratingmat- 5 ter. The object of my invention is to provide a process capable of accomplishing results equal to lithography, photolithography, and engraving. My invention'includes' the method of making the single monotone which may be used as the key print, and it also provides for reproductions having one or more colors combined with the single'color of the keyprint. In the ordinary process of lithographing a great'dealof art work on the part of skilled operators is required to prepare the stones or zines for the process and under my present invention this expensive step is eliminated. In the process of engraving there is also a considerable amount of skilled work necessary to prepare the plates and my to produce results equal to engraving, at the same time eliminating this expensive step. The present invention combines various steps some of which have been individually used in different or separate processes. It is possible, under this invention, to provide at a minimum expense a metal plate such as zinc, aluminum or any of the other so metals adapted for the purpose, which plate will have a surface on which the stock may be printed in a single color with all the fine gradations of tone, but this plate, which is adapted to be used either onan ofiset, or

fiat bed lithographic press, may be produced with a minimum of labor and without the employment of skilledlabor to prepare such plate. Where the reproductions are to be in multi-color the plate just referred to may be used as a key plate to print the key print and. subsequent impressions maybe made from the same stock from other plates prepared according to my process, and these other or color plates may also bemade at a very low cost owing to the elimination of skilled .labor, in parts of the process. While there is more or less grain in the pictures produced under this process the grain is so fine as to be almost imperceptible present process is adapted key prints.

Application med August 21, 1925. Serial No. 51,638.

to the naked eye and instead of being re lar as it is in processes where line or 5st screens are used, the grain in the present process is very irregular and therefore it is not noticeableas such in the finished pictures. Very-fine gradations of tone may be accomplished with the key print and also in the several color impressionsand various colors may be combined by superimposing colors printed from one plate upon those printed by another plate in order to increase the number of tints or colors by combination; In this respect the process is adapted to accomplish all that may be accomplished by the ordinary process of lithography. Because of the elimination of the expensive prellminary operations in preparing the plates for printing, the present method is a valuable one in runmng small jobs; that is to say, for runs up to five thousand copies, whereas under other methods of making colored reproductions the process cannot ordinarily be carried out at a profit unless the runs are from. fifty thousand copies upward. Where the job is not to exceed five thousand copies the keyprints may beprinted direct from the gelatin plate. However, the present process may be also employed for larger runs, in which case a metal plate is made from the gelatin plate for printing the Other objects and advantages will be set forth in the following detailed description of my improved process.

As a first step in carrying out. my rocess, I make a photographic negative of the subject, preferably on a film and this negative is developed and dried and is used in making the gelatin plate. The requirement simply is that a negative of the subject is obtained by photography, and this is used in making the. gelatin plate by the well known gelatin process. Assuming that the process is to start with the. photographic negative,

this is placed face down upon a gelatin plate such as is used in the well known gelatin process. These plates aregenerally made of heavy glass coated with a sensitized gelatin coating. The gelatin plate isexposed to the light transmitted through the negative, after which the gelatin plate is developed, and dried in accordance with well known methods. The gelatin plate is then treated in the same manner as for printing gelatin prints.

If the job to be run is what might be con sidered a small job of not over five thousand impressions, the key print, i. e., the paper or other stock with a monotone impression, may be printed directly from this gelatin plate as such plates are adapted to be used successfully up to about twenty-five hundred or five thousand impressions, provided the plate is kept in proper condition from time to time by the application of'well known solutions which generally contain glycerinc. If the key prints are printed directly from the gelatin plate, this may be done in the same manner as with printing ordinary gelatin prints on a gelatin printing machine.

Assuming that the process is to be carried out for a small job, the next step will be the preparation of the plates from which various colors may be printed on the key print. I then take one of the key prints which has been printed from the gelatin plate and which, it will be understood, is a positive of the picture produced on the same stock on which the job is printed; and this key print, containing preferably the complete picture which is to be reproduced, on which the ink is still fresh,is placed face down on a metal plate which is preferably made of zinc, although the same may be made of aluminum or other metals adapted for printing plates. Beforethe key print is applied to the metal plate, however, this plate must be grained by anyof the well nown processes; for instance, small shot or pebbles may be placed on the face of the metal plate and agitated thereon in order to create on the surface of the plate what is commonly known as grain.

The key print having been applied to the.

face of the grained metal plate, the plate and the key print are put into a scraper press where the fresh ink of the print is transferred to zinc. This transfer may also be made by any of the processes used by lithographcrs such as transfer powder or crayon outline or tousche outline. The print is reversed in position on the surface of the zinc plate. As the operation of transferring by means of this scraper ress is well known, a detailed description t ereof is unnecessary in the present case. This key print is printed with ordinary printers ink so that the portion which is not blocked in may be removed by etching.

A metal plate will now have the complete picture upon its grained surface represented by the ink transferred from the key print. The next step in preparing this plate for one color will be as follows: The

operator, having the complete picture before him 011 the metal plate, proceeds to block in those portions of the picture which are to be subsequently printed in a certain color. Let it be assumed that this plate is being prepared for printing in red. The operator will proceed to block in the portions of the complete picture which are to be printed entirely in red or in which red is to be combined with some other color to produce a combination color. The blocking in is accomplished by applying to portions of the picture on the metal plate material which will resist the action of the acid in the etching process. While other materials may be used for this purpose I have found tousche a satisfactory material. The tousche may be applied to portions of the picture by means of a brushand where fine gradations of coloring are required I have found that the tousche may be applied by means of an air brush. IVhen usin the tousche with an air brush it is desirable to inix the same specially for the purpose and to such a consistency that when the same is sprayed upon the plate by the air brush small globules will be formed, and these globules will remain separated from each other and effect the same result as is accomplished by the use of screens in other processes. By applying the tousche with the air brush it tends to block in portions of the picture very rapidly and to secure very fine and artistic gradations of color, and'the work may be conducted by operators comparatively unskilled. This step in the process is not limited to the use of tousche or to the use of an air brush, although in certain classes of some cases the blocking in may be performed with a graining encil. After this metal plate has been blociied in, it is etched with acid in the ordinary way, and this removes all portions of the picture represented by the ink, except those portions which have been blocked in. If tousche was used in the blocking in process, then after the etching has been completed the remaining tousche will be removed by washing the surface of the plate with turpentine and asphaltum.

For an additional color the same operation is repeated. That is to say, a transfer is made from one of the printed key prints upon a second grained metal plate, and the operator proceeds to block in this plate the same as before, except that the blocking in will be performed on such portions of the complete picture as are to be printed in another color, say blue. This operation will be repeated for as many colors as are to be printed upon, the key print.

The color plates are each put on a press and accurately positioned to secure proper work both of theseare highly desirable. In

' sion 18 made from each zinc plate, the color applied to the plate corresponding with that fonwhich'the plate was made;that is to say, when the zinc plate for the red color is on the press, this plate will be inked with red ink, and likewise when the plate for printing the blue is on the press it will be inked with blue ink, and this will be so of each plate used for printing the colors. With one of the zinc plates on the press the photo gelatin prints containing thekey picture will be fed to the press and receive an impression in one color, and the same operation will be repeated for each zinc plate. Printing may be done on an offset press or a fiat bed lithograph press, and the printing operation will conform to present practice. Where printing is done on a flat bed press it is desirable to use a soft rubber blanket on the cylinder as a backing for the stock. When the zinc plates are applied to the press no make ready, as understood in the printing art, is necessary, especially if the .1 soft rubber blanket is used on the cylinder.

If a large job is to be carried out under this process, running say from five thousand copies upward, it is preferable to modify the process in one respect. Inthis case, instead a of making all of the key prints from the gelatin plate, I prefer to make a zinc plate from which the key prints may be printed. In this case a print is made from the gelatin plate, the same as in making the color plates, and a transfer is made from this print on the scraper press, so that the stock is removed, leaving the complete picture in ink reversed in position, applied to the surface of the zinc plate. It will be understood that the latter is grained for this operation, the same as in making the color plates. Transfer ink must be used for mak ing the print used for this purpose and the zinc is treated exactly as when a transfer is made from a master plate of halftone or any other method may be employed. This plate is put into the press andused for printing the key prints on the stock. These key prints will afterwards be used in conjunction with the color plates previously described. In other words, a metal plate made accordin to a portion of my process is substituted or the gelatin plate in making the key prints, although the gelatin process is used for making the prints for the different transfer operations. The metal plate will serve for making a greater number of key print impressions than the gelatin plate first described.

From the above it will be apparent that I have eliminated the expensive art work and hand work heretofore required for making stones or plates in the present known processes. In blocking in, in the process of making the various color plates, the operator has the complete picture before him on the plate, which makes it much easier to' apply the blocking in material for each particular color. This blocking in operation is as simple as coloring a photograph, and no greater skill is required than would be required for coloring a photograph. VVheI'e an air brush is used to apply the tousche in the blockingin process, very fine gradations of color may be made owing to' the globular formation of the tousche on the plates. The final application of color to the prints may be gauged by the appearance of the tousche as applied by the air brush in the blocking in process. The pictures, as finally produced under this process,

have a very fine and irregular grain which is hardly perceptible to the naked eye, and it eliminates the screen effect usually apparent on prints made by other processes. The reason the ruled or lined screens ordinarily used in half tone work is eliminated by the present process is because of the fine pores present in the gelatine coating of the gelatine plate. These pores, which are very line and do not form a fixed pattern like the ruled screens, divide the area off into almost infinitesimal points which serve the same purpose as the lines of a ruled screen, except that they are finer then even the best screens. One great advantage of the present method is that the prints may be made on uncoated stock, producing a more artistic appearance, although it will be understood that the method may be also carried out on coated stock as well.

Having described my invention, what I claim is:

1. The method of preparing a metal plate for the purpose set forth, which consists of making a key print from a gelatine plate, making a transfer from said key print onto the surface of a metal plate, blocking in portions of the transferred image on said metal plate and treating said metal plate to remove portions of the image not covered by the blocking in operation. 2. The method of preparing metal plates for the purpose set forth, whlch consists of making one or more key prints from a gelatine plate, makinv a transfer of similar images from the key prints onto the surface of each of a plurality of metal grained plates, blocking in different portions of the ing blocking in material to portions of the image on said metal plate by means of an air brush and then etching said metal plate.

, 4. The method of preparing a metal plate for the purpose set forth, which consists of making a transfer from a gelatine plate upon the surface of a metal plate, then applying to portions of the image on said plate,

by means of an air brush, tousche of a con-