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Aug. 23, 193s. A. A. LEUCHTER 2,127,824 PRINTING MEMBER FOR INTAG'LÍO OR ROTARY PHOTOGRAVURE PRINTING’ Filed April 1751928 `\>\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ ï 'E;[l /I A. ~ \\\\\\\\\\\\\\\\\\\ l /A \\ \\\\\\x\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ /N l ’EN TOR A uga/sf A ¿e (fc/#er f1 TTORNE Y Patented Aug. 23, 193s . l t l 2,127,824 UNITED STATES VPATENT oFFlcE 2,127,824 PRINTING MEMBER FOR INTAGLIO OR ROTARY PHOTOGRAVURE PRINTING August A. Leuchter, Augusta, Maine Application April >1'7, 1928, Serial No. 270,639 5 Claims. (Cl. 101-_-401) Intaglio or rotary photogravure printing is mostly done from cylindrical surfaces, each of Such cylinders chiefly consisting of an iron core, mounted upon a steel shaft, and carrying on its 5 outer periphery a. layer of’copper, which when ground and polished to perfection, is etched upon. and serves then as the actual printing-surface of such cylinders. » ` o Usually such layers of copper are produced bring about such condition of a substantially disconnected electrolytic deposit, the cylinder body is purposely prepared in such a way, by either oxidizing its surface or otherwise laying on an interference film, that the growing-fast 5N of such an on-coming electrolytic deposit to the cylinder body is positively prevented in the proc ess of electro-deposition. , While such and other similar methods pos 10 by electrolytic deposition directly upon the iron body or core of such cylinders, and are carried to a thickness suitable for receiving from twenty to thirty etching in succession. Under the gen- readily detachable shell-like deposit, and vdo fa cilitate the stripping-off of the deposit whenever its removal is desired, certain distinct disadvan -eral proceedings‘of carrying out the successive tages are entailed by such methods, inasmuch as l5`etchings upon vsaid outer layers of copper, it is customary to remove an etched-in-surface, bear- sibly offer certain advantages by producing a l0 ~ a printing surface, and especially an intaglio 15 one, shouldl have an absolute tight and solid ing images to be reproduced by what is known connection throughout with the underlying cyl as “gravure" or intaglio-printing, by the process of grinding and afterwards re-polishing the face 20 0f said layer of copper in order to receive the next etching. inder-body, because in the process of printing from such a cylinder, commonly known as roto gTavure printing, considerable pressure is ex- 20 erted by the impression-roller against the etched Under this commonly _general procedure .the surface of the printing cylinder in order to force ' diameter of such ` printing-cylinders is being the paper, passing between them„most thorough constantly reduced for such successive etchings,v _ly down into the depressions .of the etchings, 25 and it is not possible therefore to retain any in order to receive the full value of tone-grada- 25 I iìxed standard diameters of cylinders, except a tion by the varying density of ink carried in thc ground-olf outer section, which had carried a etched-in images of the printing surface. previous etching, were re-built, and thus the cylSince best results can only be had in intaglio inder brought back to Vits former diameter by an or rotary photogravure printing by exerting con 30 additional deposit of copper. siderable pressure against the printing-cylinder, 30 Since it is highly desirable to maintain a fixed it is clearly obvious that a loosely laid-on shell, standard diameter for such printing cylinders, lWithOllt any intimate and Solid Connection With and to avoid the .process of grinding-oil' used the Vunderlying cylinder-bodl/„Can not present printing surfaces, and gradually re-ñnishing the an ideal printing surface, kconsidering the press 35 newly exposed copper surface to make it suitable OperatiOn 8.10116. but Other and greater Objeû‘ 35 Jfor receiving a 4IEW etching thereon, but at the tionable features are present ywhen the _etching required expenditure of from eight to ten hours and preparation of the printing surface in gen oi' time‘and effort, different means~ have been eral is carried out. ì 4 suggested and devised to dispose of such used In such latter operation, in order to get best I 40 printing surfaces, and to replace them in much o effects, considerable retouching, tooling,_ re-en- 40 l shorter time by new deposits of the same thick- , graving and the like are commonly practiced, ness, thereafter made ready to lreceive a new etching. " One of `such means, embodies a method Where45 by a thin layer 0f Copper is deposited upon the cylinder body without becoming solidly attached t0 the Same. except at the two extreme ends of the cylinder, but otherwise forming a loose detachable shell extending all over the periphery 50 of the cylinder, which feature enables the removal of such a shell by shaving or cutting through the two extreme solidly connected ends of the same, whereupon such shell can be readily removed from the cylinder body by peeling, after 55 a lengthwise incision is made in the same. To and must be resorted to, and such work is nat urally more safely and practically carried out on a solidly connected layer of copper than on a loose shell, where there is always danger of cut- 45 ting-through in any operation of hand-tooling, or the-loosening of such a shell in spots by burn ishing, or by having any ink work its way un derneath through any possible pores in sucha shell-deposit, and eventually may causea loosen- 5° ing or buckling of such deposit in the process of printing. - ' It is for this reason that such method of preparing and producing of printing surfaces by means of a detachable shell has not met with u 2,127,824 2 ‘ approval and is more or less objected to when cylinders for intaglio-printing in color are to be prepared, involving far more .exacting conditions and more retouching in order to reach desired effects in the varyingï depths of the etching. Therefore it is one purpose of the present in vention to overcome and eliminate all such ob jectionable features and deficiencies entailed by the practice of a loosely laid-on shell-deposit to 10 form the actual printing surface of a cylinder, , and to produce by a different proceeding a print ing surface of an electrolytically deposited layer of copper of suitable thickness to receive and carry an intaglio etching; but such layer of cop 15 per is so intimately and tightly deposited onto another layer of a hard metal, which forms the outer periphery of the cylinder body, that re moval of the deposited layer of copper is not pos sible by any mechanical stripping method, but ~ could only be accomplished by either grinding, or turning-off in a lathe, or else by electrochem ical dissolution in an electrolyte, or by other chemical disintegration in reconverting the me tallic copper into a copper-salt or oxide. While I have under my newly devised method of producing removable printing surfaces, either cylindrical or flat, a choice of three distinctly dif ferent ways to effect such removal, I prefer the one of electro-chemical dissolution as the most practical and economical one, whereby I am en abled to re-deposit the copper-layer from the cyl inder surface back onto the anode plate, thus saving from eighty to eighty-five per cent. of the originally deposited copper, that is, of the le, layer first deposited to form the printing sur face on the cylinder; and naturally such saving of copper repeatedly takes place every time a used printing-surface is removed to become re placed by a new deposit. _ With such objects in view, my invention con sists of novel features in the printing member, such as cylindrical or flat, and in certain process steps, to be hereinafter described and then claimed, with reference to, the accompanying : drawing, illustrating the invention as prefer ably applied to a printing cylinder, and in which: Figure 1 is a longitudinal section before the .copper deposit is formed, and Fig. 2 is a similar section after the deposit has been made. In the drawing, a steel shaft 5 has the core 6 of the printing cylinder mounted and fixed therein in suitable well known manner. This is but one form of printing cylinder to which the 55 invention may be applied. To make the removal of a used printing sur face possible by electro-chemical dissolution of the copper, and in this way convert it back onto theanode-plate, it is necessary to carry on the cylinder body 6, and to constitute the' base for the final layer-of copper forming the actual printing surface, a layer 1 of hard metal, capable of receiving and mechanically and intimately combining with the on-corning electrolytic de 65 posit at the time such final layer 8 of copper is grown thereon by electro-deposition; and also on the other hand, when the removal of such body 8 of copper is undertaken by electrolytic action, said layer 1 of hard metal must also be capable 70 of resisting corrosion and dissolution in the electrolyte under the influence of the reversed current, when this layer 1 of hard metal must then actually serve as an insoluble anode, and remain immune to any reaction of both the cur rent as well as the copper-electrolyte usually em ployed. The electrolyte is the usual acid copper bath. The speed of rotation of the cylinder during electro-chemical treatment may approxi mate 200 revolutions per minute, for example. Since a used intaglio printing surface natural ly consists of an unevenly-thick layer 8 of cop per, due to the fact that the same carries the etched-in images of varying depths, it follows that in the course of electrolytic dissolution the etched-in sections of such layer of copper be 10 come dissolved first, by reason of being thinner, thereby exposing the layer 'l of hard metal un derneath in those sections, and which now must remain unaffected, while gradually the copper is being dissolved completely all over, the thicker sections taking the longest. - When all traces of the copper layer 8 have disappeared, and the layer l of hard metal is now completely exposed, it is only necessary to break the reversed current connection, under 20 which the cylinder had been made the anode terminal, and the anode-plate been the cathode terminal in the electrolyte, and after brushing the cylinder with the hard metal layer, all bare on its outer surface, clean from any scum or foam 25 of a gaseous formation, a new deposit may be formed again immediately, by throwing the re versible current switch back into its normal po sition, when thereby normal current connections become reestablished in the depositing-tank, and 30 the cylinder is made again the cathode-terminal in the depositing solution, and copper-depositing proceeds again onto said layer of hard metal 'l until the desired thickness of copper layer 8 is reached, which latter is determined by the am 35 pere-amount of current flowing in a given pe riod of time. As this layer of hard metal remains entirely unaffected by any reaction of either current or depositing solution, no change in size of cylinder 40 body will take place, thereby assuring standardiz ing sizes of cylinders, which under the old method of grinding olf the used printing surfaces and thereafter re-ñnishing, to facilitate etching-on of new printing-images, was not possible, but causes 45 constant reducing of cylinder sizes with every new etching effected thereon. Summing up the foregoing it becomes evident ' that the outstanding feature of this invention is an absolutely solid and perfectly united non-. 50 stripping layer of copper on the outer surface of a cylinder body, whereon all the usual operations of etching, retouching and tooling, as become neces sary in the preparation of intaglio printing sur faces, may be carried out with utmost security 55 and no danger of causing the said thin layer of copper to come loose or lift from the cylinder body; neither would any amount of pressure in the printing operation have any detrimental stretching effect on same, nor could even a local grinding operation effect a loosening of its hold on the underlying body. In making an individual deposit for every etch ing, only a thin layer is necessary, requiring at best only polishing; and due to the fact that the 65 removal of the used printing face can be accom plished by electrochemical dissolution, and there by the layer of copper be transferred from the cylinder back onto the anode-plate, and as the same would be repeated with every renewal of the 70 printing face of a cylinder, a great saving of copper is realized especially in the continuous run. For example, the thickness of the copper may be from three to six thousandths of an inch, and the 75 hard base preferably thicker. 2,127,824 3 All such achievements are solely due and pos sible only by the creation of a layer 'I of hard and this necessarily hard and impervious layer of Cl softer metals the latter may consist of, and be there also it is obligatory to deposit a heavy enough layer of such metal; so thatthe- pushing and pulling power of the electric current passing through the cylinder-body and on towards the cathode surface, in its very act of dislodging and by the use of nickel, or a combination there impervious metal completely encasing the iron 'metal of with traces-of chromium or platinum injected; core 6 of the cylinder body, or such other layers of directly underneath and adjacent to the final layer of copper, which has to serve as the actual 10 printing surface of a cylinder. 'I’he evident purpose of this layer 'l of hard dissolving said copper layer by electrolytic proc impervious metal, preferably consisting of nickel, or a combination thereof to increase the corrosive > resistance, is to form a permanent base for the layer of copper constituting the actual printing surface, with which it must most intimately unite; but also on the other hand the base layer ’I must serve as a positive protection against corrosion and disintegration of the- cylinder body, of which it is a. most vital part, when dissolution of the copper layer is enacted and carried out by the electro-chemical process for the purpose of re moving a used printing surface. In creating such a layer 1 of impervious hard metal the invention is not conñned to the employ ment of nickel, but there could be used any other metal capable of resisting the corrosive action of the copper electrolyte combined with the in fluence of the reversed electric current, under which condition the cylinder-body actually be ' comes the anode-terminal, and must then assume all properties of an insoluble anode, as soon as any etched sections of the copper-layer have yielded to electro-chemical dissolution, and the layer of the impervious metal underneath becomes ex posed, since it is only in such way that the disin tegration of the cylinder-body below said final layer of copper is positively prevented, and thus a permanent unaffected base for said outer layer of copper is created. _ Other metals of like corrosion resisting property 40. that might be considered for such purpose would be chromium, platinum and also lead, but it is preferred not to use either of these for the reason of being highly expensive, as is the cost of platinum, or a perfect union with the final layer of copper is not possible, but might only be used when a detachable copper-shell Ais desired with a view of stripping or peeling-oli' bodily; and finally a layer of lead is at best only a very soft body and very difficult to maintain in perfect physical con dition, especially when considering that one prin cipal requirement of this invention is the creation of a hard impervious layer of metal, capable of being brought to a true and high finish and so maintained during the continuous practice of building-on and taking-off said layers of copper, serving as printing-surfaces of cylinders.- " Besides, layers of such other metals are diilìcult to produce in the required thickness but answer at best for a light plating'only, which would prove 60 useless for this purpose, because, while in such state they might temporarily resist the corrosive action of the copperelectrolyte, they could not resist the powerful influence of the electric cur rent passing through the cylinder body `as an anode and outwardly therefrom towards the cath ode surface, and due to which tendency there is caused a loosening and lifting-up of any such lightly plated film or pellicle of the respective metal, and then of course, the cylinder-body would no longer represent an insoluble anode, but be subject to attack and disintegration, thereby ruining the same, and making the whole operation of removing such an outer copper-film a complete failure. -This very same tendency prevails in creating ess, has no longer- any such ruinous effect on the 10 layer of nickel. . It is evident therefore that Whichever corrosion resistance metal is used for creating such an im pervious metallic layer, the same must be carried to such thickness that the powerful _iniiuence of the reverse flowing current can have no loosening or lifting influence on such _a layer, and cannot disturb the same in the least. 'I‘herefore it is preferred to create such im pervious metallic la'yer of nickel, as that is reas 20 onable in cost, and the electro-deposition of the same can be carried to any ,desired and almost unlimited thickness with ease, and furthermore nickel possesses great tensile strength besides hardness, and may be turned or ground true, and also brought to a high surface-finish, which it is apt to retain due ‘to its hard and non-corrosive nature, and in general it is the ideal metal for this very purpose. , The encasing of the cylinder-body with nickel 30 is even carried to vfar greater‘thickness than it is necessary to resist any detrimental current action, for the reason that it affords and brings about greater rigidity of the cylinder-body, usually con sisting of cast iron and copper, and thereby pre vents any sinking of sections of the cylinder periphery, and in general helps to keep the cylin der in perfect shape and true condition. What I claim as new, is: 1. A printing member having a permanent base 40 of hard, impervious, non-corrosive metal, and a thin outer layer of a different kind of metal for providing a rotary photogravure printing surface and which throughout its entire area is intimately and solidly united with such base, and which layer 45 is- of a character suitable for etching such print ing surface, the outer layer being sensitive to electrolytic dissolution of its _metal and the metal of the base being neutral thereto. 2. A printing member, including >a main body, a layer of hard, impervious, non-corrosive metal -50 intimately united with the body, and forming a permanent base, and an exterior thin layer of softer metal for providing a rotary photogravure printing surface and which is intimately andl solidly united throughout with such base, and 55 which'exterior layer is of a character suitable for etching such printing surface, the exterior layerbeing sensitive to electrolytic dissolution of its metal and the metal of the base being neutral 60 , thereto. 3. A printing member, including a main body, a layer of hard, impervious, non-corrosive metal intimately united with the body, and forming a permanent base, and an exterior thin layer of copper for providing a rotary photogravure print ing surface and which throughout is intimately and solidly united with the base by electro deposition, and which exterior layer is of a char acter suitable for etching such printing surface, 70 the exterior layer being sensitive to electrolytic dissolution of its metal and the metal of the base being neutral thereto. , y 4. A printing cylinder, including a core, a shaft on which it is ñtted, a layer of hard, impervious, 4 2,127,824 non-corrosive metal extending all over the cy lindrical surface and ends of the core, and an exterior layer of copper intimately united with the layer of hard and non-corrosive metal by electro CH deposition throughout the whole surface area of the hard, non-corrosive layer, and the cylindrical surface of the copper layer being of a character suitable to provide a rotary photogravure print ing surface. 5. A printing member having a main body with l() a permanent nickel base electro-deposited there on, and an exterior thin layer of copper directly electro-deposited on the base, and which depos ited layer of copper has a depth slightly more than sufficient for one etching, and is of a char acter suitable to provide a rotary photogravure printing surface and throughout is intimately and solidly united with the outer surface of such base, the base being the harder of the two metals. 10 AUGUST A. LEUCHTER.