US985664A - Process of making toned printing-plates. - Google Patents

Description

M. A. DROITGUR. PROCESS 0I MAKING TONBD PRINTING PLATES.' APPLICATION 211.111) APE. 16, 1'910.

985,664. yPatented Fenzs, 1911.

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MICHAEL DROITCO'UR, OF CHICAGO, ILLINOIS, ASSIGNOR TO MIEHLE PRINTING PRESS AND MANUFACTURING COMPANY, F CHICAGO, ILLINOIS, A CORPORATION 0F ILLINOIS..

PROCESS 0F.1VIAKING TONED PRINTING-PLATES.

- Specification of Letters Patent Patented Feb; 28, 1911.

Application filed April 16, 1910. .Serial No. 555,830.

1 State of Illinois, have invented certain new and useful Improvements` in Processes of Making Toned Printing-Plates; and I hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, which form part of this specification.

This invention is an improvement in the art of making made-ready or toned printing plates, in which the desired lights and shades in the impression taken therefrom are obtained by varying the surface of the printing plate itself, so as to obtain greater pressure at the points where the darker prints are desired and less pressure at the points where lighter impression is desired. i y.

The object of the present invention 1s to produce the desired tones in the printing plate during the process of making the shell or surface of such plate, so that the printing surface of the shell will be toned prior to the completion of the making of the shell and at a time when it will'be possible to effect the toning with the least possible distortion of the metah and whereby the most delicate variations in tone can be obtained .ence to the accompanying drawings Which illustrate various stepsin my novel method of preparing a toned printing plate, and will enable'any one familiar with the art to practically utilize the invention; and I refer to the claims for summaries of the novel features and 4steps in the process for Which protection is desired.

Figure 1 is a fl'agrammatical elevation of an original printing surface or type form, and a Wax sheet and backing preparatory to forming the mold or matrix` in the wax from such surface. Fig. 2 is a diagrammatical view of a Wax mold or matrix Witli'a metallic skin or partially formed very thin shell' depositedthereon. Fig. 3 illustrates diagrammatically the toning of this skin or partly formed shell. Fig. l illustrates diagrammatically the complete toned shell i.

formed by depositing additional metal upon the toned skin. Fig. 5 shows 'one Way et backing' up such shell tov forin a printing plate. Fig. 6 is a diagammatical sectional view of a finished printing plate.

In one method embodying the invention a wax mold or matrix is formed in the ordinary way, as for instance by ini wes-'ing' a sheet of wax -VV attached to a suiml ie backing fw, upon a printing surface`or type form T which may rest upon a suitable bed. By the termv Wax I intend to include any suitable material which is ordinarily used, or may be used, for receiving 1an intaglio irnpression from the printing surface, and upon which may be subsequently deposited a metallic shell, as indicated at S, Fig. gt. The means for and mode of forming such shellsas by electrotyping-being wellknown, requires no description herein.

In accordance With my invention after a thin skin of metal has' been deposited upon the face of the'jvax matrix, as indicated at s in Fig. 2, the depositing of metal on the mold is'suspended and this skin is toned by impressing the ,wax matrix and skin on the form after a previously prepared overlay O has been placed on the form as indicated in Fig. 3. Said overlay may be .of any Well known or desired construction,-for instance an etched vzinc plate, or a chalk overlay, or a cut paper overlay, which are now commonly used; and well understood in the art. The overlay being constructed so as to be thinner at places corresponding to those portions of the printing surface which it is desired shall have less pressure during Y the taking of an impression; and thicker, at the places corresponding to the portions.

loo

of the printing plate which it is desired shall the wax matrix and the metal skin s deposited thereupon are toned in accordance With the overlay O, so that the surface of the wax matrix, and the skin s instead Qf remaining absolutely plane surfaced, is 'depressed, more or less, where it contacts with projections on the overlay and in accordance n with the size and thickness of 'such projec tions.

The thus f toned Wax mold and metal skin thereon, are then removed from theform and additional metal deposited upon the skin in the usual manner to form with or convert such skin into a metal shell S (Fig. 4) of'the usual thickness.

On account of the previous toning 7 of the skin as described,' the completed shelly printing surface,-siich surface being already toned in accordance with the overlay. It Will be observed that the tones of the i plate are determined and 'formed before the shellv is completed, so that the shell itself does not have to be distorted after formation in order to tone ita-noi' does the completed plate have to be distorted in order to tone it.

The plate may be backed in various ways; as indicated in the drawings, Fig. 5, I prefer to lay the shell face downward upon a suitable bed B Within a chase C, and `pour suiiicient molten metal M into the chase to form a plateof the desired thickness. After the metal is set the plate is removed and reduced to proper thickness, and plane siii'- facedl on the back, by removing any surplus metal; as by planinlr it along the line m Fig. 5; the resultant J ate after itsedges are trimmed being rea y for printing, as indicated in Fig. 6. Of course the thin metal skin s becomes an integral and indistinguishable part of the shell S, and I have simply illustrated it diagrammatically in the drawings to facilitate t-he explanation of the inveiit-ion.

I preferably support the face of the shell Swhile applying` the backino M thereto and While planing the back of1 the plato, by means of an overlay U, Fig. 5, as described in my Patent No. 952,312 of March 15th, 1910, in order to prevent any .distortion of the shell by the Weight and heat of the molten metal poured thereupon to back it, or the distortion of the printing surface by the pressure of the planers or grinders used to reduce the plate to the desired thickness, and its back to a uniform plane surface.

Butthis overlay in the present instance is not, used in an sense to tone they plate, the toning beingge ected as above described during the formation, but prior to the coiiipletion of, the thin type surface or shell.-

Having described my invention what I,

claim is: l

- v1. The herein described method of making toned shells for printing plates, consisting' in forming a matrix, producing a skin of inetal on the face of the matrix, toning the skin of metal by pressing the same against a suitable toning surface, and then supplying sufficient metal to the toned skin to form a shell. i

The herein described method of making' toned printing plates consisting in forming 3. The liereindescribed method of making toned printing plates, consisting in deposit'- ing a thin skin of metal upon a suitable mold or'inatrix, toning the matrix and skin by pressing same against an overlay; then depositing additional metal 'to the skin to form a shell; and subsequently backing such toned slill to form a printing plate.

4. 'Ihe herein described method of making toned shells for printing plates, ctnsisting in taking an impression on a Wax sheet to form a matrix, depositing upon this matrix a skin of metal, toning this skin by impressing it while on the matrix against a suitably prepared toningir surface, and thickening the skin to form a shell by depositing additional metal thereon. f

5. The herein described method of making .toned print-ing plates, consistingin taking an impression on a Waxsheet to form a ina-A trix, depositing upon this matrix a skin of metal, toning this skin by impressing it while on the matrix against a suitably prepared toning surface, thickening the skin to form a shell by deposit-ing additional metal thereon; and subsequently backing the toned shell-to forma printing' plate, substantially as described'.

6. The herein described nietliod of making toned printing plates, consisting first in making a matrix by impressing a plastic sheet upon a printing surface, depositing a skin of metal upon the matrix; placing a suitably prepared overlay upon the printing sur face and pressing the` matrix With its skin of metal against the overlay upon the printing surface; then backing the toned skin to forni the plate. 7. The herein described method of making toned printing plates, consisting in taking an impression from a printing surface upon a wax sheet, depositing a skin of metal upon the impressed surface of the Wax sheet; placing a suitably prepared overlay upon the printing surface and pressing the wax sheet with its skinof metal against such overlay, then depositing additional. metal upon-"the toned skin to form a shell, and finally removing the wax sheet and applying a suitable backing to the tonedshell.

K 8. The herein described method of making toned printing plates consisting in taking an impression on a Wax sheet to form a matrix,

- depositing upon this matrix a skin of metal,

toning this skin by impressing it While on the matrix against asuitably prepared toning surface; thickening the skin to form a shell by depositing additional metal thereon; applying sulicient metal to the back of the toned shell to form a printing plate, and

finally trimming the finished plate.

9. The herein described method of'making toned printing plates, consisting in taking an impression from a printing surface .upon

a wax sheet,.depositing a slfin of metal upon the Wax sheet; placing a suitably prepared overlay upon the printing surface and pressing the Wax sheet.with its skin of metal agai st such overlay; then depositing additional" metal upon the toned skin to form a shell; removing the Waxsheet;- applying an underlay to the face of the shell to prevent Copies of this patent may be obtained for -of the shell -to form a by pressing 'same against a suitable toning surface; depositing additional metal on the toned skin to form a shell; placing the toned shell face downward on a suitable support, applying an underlay to the fa ce of the shell to prevent distortion thereof during the backing of the shell; applying metal to the back of the shell to form a plate; and finally reducingthe plate to the desired thickness while the face of the shell is supported by 4the underlay, substantially asdescribed.

In testimony that I claim the foregoing as my own, I aiiix my signature in presence of two Witnesses.

MICHAEL A. DROITCOUR.

Witnesses AELMER HASSMANN,

SYLvIA WILLS.

ve cents each, by addressingthe Commissioner of Yaten'ts, Washington, D. C.

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