US2456608A - Type for gravure printing - Google Patents

Description

Dec. 21, 1948. H, c, A G 2,456,608

TYPE FOR GRAVURE PRINTING Filed Oct. 24, 1942 Patented Dec. 21, 1948 TYPE FOR GRAvUnE PRINTING Harley C. Alger, Chicago, Ill.

Substituted for appiication -Serial No. 69,005, March 16, 1936. This application October 24, 1942, Serial No. 463,232

- 2 Claims. (Cl. 101399) The present application is. a substitute or substantially a substitute for my prior application for Gravure printing, Serial No; 69,005 filed March 16,1936 (now abandoned).

This inventionrelates generally to the improvement of certain printing characters such as type or the like, when used in intaglio or gravure printing and is particularly directed to printing characters for gravure printing and to proofs for producing such characters.

One of the objections to printing, done by the gravure process is the roughness or irregularity of the edges of type and other characters which is caused by the method in use at present in which the screen is printed on the sensitized gelatin commonly called carbon tissue and subsequently the type or other printing characters are printed on the same surface either by means of the camera or by printingfrom a positive in contact with the carbon tissue as is commonly done. This double printing produces in the gelatin a surface, hardened to a depth which depends upon the amount of light to which the gelatin is exposed. The areas where the characters occur remain rather thin except where the lines which are hardened to a greater depth pass through the thinner areas. When this carbon tissue is applied to the cylinder or plate, developedfand dried, and the cylinder or plate is etched, the characters are formed in the surface of the metal of the cylinder or plate by small cells or wells, usually rectangular, surrounded or defined by the lines left where the hardened screen lines in the gelatin protected the metal and prevented its etching. The face of the type or characters in the metal is therefore formed by a series of cells covering the area of the characters and along the edges of the characters there is formed an interrupted or irregularrow of cells, which cells carry the ink, with raised walls or lines between which do not carry ink. As a print or impression is made from these'characters, these cells, transfer their ink to the paper, thus producing rough or interrupted edges around the characters instead of giving sharp lines or definition.

One of the objects of my inventionis to avoid such objections and to provide improved type of printing. It also includes a new and novel proof for producing type or other printing characters in gravure printing surfaces, either cylinders or plates, which print by the intaglio process, and the method of making the proof and to its use in making gravure cylinders or plates.

Another object is the production of printing characters which may be etched in cylinders or plates, which are usually made of copper, in such a way that they will print clearer, sharper characters than those heretofore produced.

Another object is the elimination of several steps in the present method of producing printing characters in such cylinders orplates while other objects and advantages will appear more particularly from the following description, taken in connection with the accompanying drawings, in which Figure 1 is a view of an improved proof made in accordance with this invention;

Figure 2 is a sectional view of a matrix or type mold;

Figure3 is a plan view showing the bottom surface of the mold;

Figure 4 is a plan view of the type made from the mold;

Figure 5 is a plan view showing the final printing of the letter or character as made from the plate or cylinder; and

Figure 6 is a view of a proof made in accordance with this invention showing one arrangement of the lines, in a type face, which correspond to the lines used to support the doctor blade during the operation of printing.

In accordance with my invention, I produce characters in the metal or printing surface with definite sharp outlines while at the same time they are provided with cells or wells which aid in carrying and distributing the ink evenly over the face of the characters so that they will reproduce sharply and evenly when printing. These all are so shaped and positioned that they tend to hold the ink and prevent it from being drawn out or dislodged by the doctor blade. Also where the characters are large, I may provide the equivalent of the lines through the characters H which will support the doctor blade commonly members or printing characters for such forms used to scrape ink from the cylinder or plate in this form of printing, while at the same time producing characters in the metal with definite sharp outlines.

My invention consists in or includes making a proof 6 as shown in Figure 1, having type or characters E and 8 to be reproduced, which characters have continuous or sharp outlines as indicated at 9 to define the peripheries or borders thereof. These characters also have lines or the like it formed therein or on the face thereof which break the continuity of the faces of the characters into small areas corresponding in general to the cells or depressions of the ordinary gravure printing surface. This proof is usually made with characters having a dense tone with lines of light one therein which is commonly called a positive, or it may be made in reverse by well known methods, that is, with characters having light tones with lines of dense tone therein which is commonly called a negative. My invention may consist further in the particular method by which such proof is made and in the method of using the same to produce a gravure printing surface.

In carrying out one method, a matrix such as shown in Figures 2 and 3 is made in the usual manner except that ridges or projections of any desired shape it are formed in the face thereof which leaves lower portions or depressions it between said ridges or projections which are on the level with the face of the matrix. These projections or ridges may comprise two sets of ably pointed or narrowed where they come close to the periphery, as shown.

The proof or positive as shown in Figure 1 may be black on white paper with the main areas black and with the lines or dividing portions l0 white. the black, of course, forming a space around the entire edge of the type as indicated. The lines may be merely parallel lines or may be cross lines or lines distributed in any desired manner which will be particularly adapted for use in small characters as cells having a dimension of from one one-hundredth to two one-hundredths of an inch in width will serve to carry the ink.

The proof made in accordance with my invention consists in general of the desired wording or subject matter composed and reproduced on a suitable sheet either photographically or by printing with ink, using characters made in accordance with the above description, one procedure being to provide matrixes as above described for a. mono-type casting machine or for a linotype" machine and cast or compose the type in the usual way and print the type with opaque ink on a sheet of transparent material to form a positive which may be used to print in contact direct onto the sensitized carbon tissue without printing the regular gravure screen thereon. To

. complete the'making of the gravure printing on substantially straight, lines at right angles to 4 each other similar to the lines in the conventional gravure screen commonly used in the regular gravure process but in any event preferably terminate short of the boundary portions or edges of the letter or character to be produced in order to prevent any broken or ragged appearance along the peripheral margin of the letter. Such lines or projections may be in the form of grids or may be of any suitable shape or arrangement such as parallel lines, irregular lines, crosses, dots, dashes, or any form which may serve the desired purpose. Or they may consist of one set of parallel lines or lines of irregular shape so placed that they will produce raised line surfaces in the finished printing cylinder which will prevent ink from being drawn out or dislodged by the action of the doctor blade. These raised line surfaces should be surface high on the cylinder to support the doctor blade in large characters, while in small characters where the doctor blade needs but little support, they may be slightly below the surface of the cylinder. These lines although thin are preferably narrowed or pointed at their ends which come close to contact with the periphery of the character. In view of the fact that these lines,

projections. or the like, stop short of the edges of the face of the matrix, a definite sharp outline will be provided for the character as will appear later.

Figure 4 shows the face of a relief type cast or molded from the matrix of Figures 2 and 3 and in this the lines I3 indicate grooves or depressions in the face of the type which conform to the lines or ridges ll of the matrix, the face of the type being shown by the white areas Hi. It is also to be noted that the recesses or grooves i3 do not run through to the edges of the type but leave face-high surfaces around the edge of the type as shown at W, which maintains the sharp outline desired. The ends of the recesses are preferthe cylinder or plate, usually made of copper, the positive is printed onto the sensitized gelatin coating or carbon tissue. The coating is then applied to the metal printing surface of the cylinder or plate, developed and dried so as to act as a resist to the etching acid and the printing surface is then etched with acid to produce the characters in the form of small cells in the surface of the cylinder or plate, such characters having the desired sharp or continuous outline as heretofore described.

In addition to making the positive by printing from the type or by making it photographically by printing a proof of the type and then making a negative and subsequently a positive from said negative by the photographic process, there is a third way which has some advantage in reproducing this type with its rather thin line recesses. In this latter method, the type form itself is photographed directly. The type form is first planed level, it is then sprayed with lamp .black, filling the recesses and the type face and also the remainder of the type metal at the root of the type. Next, the type is carefully rubbed with a photoengravers rubber. This removes the lamp black from the type faces, but not from the recesses or remainder of the form. A photographic plate or film is then made of the form, the exposed metal being gray will record black on the plate if suitable emulsion is used and results at once in a positive which more faithfully reproduces the fine recesses.

From this description it will be seen that I provide a novel proof for the purposes described, together with means for making the same, but it will be noted that modifications may be desired for diflerent forms of work and therefore I do not wish to limit the invention to the particular method of means shown except as specified in the following claims.

I claim:

1. A relief type member having a flat printing surface consisting of continuous peripheral walls and a plurality of protuberances more or less uniformly distributed throughout the area bounded by said walls, each protuberance being on the order of from one one-hundredth to two onehundredths of an inch in width and being separated from adjacent protuberances by a groove substantially narrower than the minimum printing surface dimension of the protuberance, said groove being narrowed and pointed at the ends near the periphery of the member and said walls being substantially thinner than said dimension said flat printing surface being adapted to transfer ink from its walls and protuberances while printing and to leave bare the areas corresponding to said grooves.

2. A type for use in making a gravure proof, having a flat printing surface with continuous peripheral walls and a plurality of protuberances of from one one-hundredth to two one-hundredths of an inch in width distributed throughout the area bounded by said walls, said protuberances being separated from adjacent protuberances by narrow grooves having sharpened ends which terminate close to the peripheral walls, said flat printing surface and protuberances being adapted to carry ink while said grooves are free from ink.

HARLEY C. ALGER.

REFERENCES CITED The following references are of record in the file of this patent:

OTHER REFERENCES Commercial Engraving and Printing, Heckleman (1921), pages 567, 568, and 569.

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