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0a. 25,1938. 2,133,981 P. A. FRAZIER PRINTING ELEMENT AND METHOD OF MAKING AND USING SAME Filed March 29, 1935 J5 3 Iraq grim? * ' ' cw raz bar" Patented Oct. 1938 1 UNITED STATES PATENT OFFICE 2,133,981 PRINTING ELEIVIENT AND METHOD OF » MAKING AND USING SAMIE Philip‘ A. Frazier, Oak Park, 111., assignor to Frazier Processes Incorporated, New York, N. Y., a corporation of New York Application March 29, 1935, Serial No. 13,629 12 Claims. (Cl. 101—401.1) ing process and thus furnish a greater degree of support behind the high spots or lands of the mounted plate, to the end that the mounted plate is adapted to provide a substantially uniform impression in the printed areas despite slight in- -5., provision of novel means for and method of sup accuracies in the press in which the plate is used porting a relatively thin printing plate, such as and without make-ready, that is to say, the ac the electrolytically deposited shell commonly used ' curate adjustment of all of the high spots of the plate with respect to the press. in making up an electrotype, in position to per Another important object is to employ a resil- 10 10 form its printing function in such a way, that ient. medium, including metal, as a backing for the lands or high spots of the plate, which ac My invention relates in general to the art of printing, and more particularly to that phase of printing concerned with the mounting of the printing element. 5 The invention has, for an important object, the complish the printinglby applying ink to the sur faces being‘ printed, are supported relativelymore a shell-like printing plate. ?rmly and rigidly than are the valleys or low of latex and a metallic ?our to form a resilient backing for a shell-like printing plate. 15 15 spots of the plate, to the end that the printing ‘ may. have sharp de?nition between the inked spaces. ' Another important" object is to provide for mounting a thin, shell-like printing element, such 20 as is used in electrotypes, yieldingly in printing position, the plate being yieldingly supported throughout its entire area, whereby printing pres sure between the plate and the surface being printed may be substantially uniform throughout 25 the area of the plate, to the end that the result ing printing is of uniform texture. Another important object is to provide for backing a shell-like printing plate with resilient ' material, such as rubber, to improve the printing :0 characteristics of the plate; a further object be, ing to apply the rubber in substantially raw con dition in order that the same may ?ow into the crevices in back of the plate so as to provide a backing at all points within the area of the 35 plate, and then vulcanize the rubber in order to cure and solidify it in place. Another important object is to provide for vul canizing the rubber backing to v»'diii‘erent' degrees of hardness in order to a?ord greater support 40 behind certain portions of the plate while permit ,- ting other portions of the plate to yield when , =- _ Another important object is to utilize a mixture Another object is to provide a backing tor a shell-like printing plate by applying a metallic medium on the back of the shell to a depth su?i cient to ?ll the depressions, then shaving the backing medium and applying a resilient medium 20 behind the shaved material in order to provide a resiliently mounted printing element. Another object is to back a shell-like printing element by spraying a metallic backing medium upon said element. , 25 Another important object is to provide a back ing for a shell-like printing element by spraying the back of the shell with liquid latex and then curing the same in. position on the back 01' the shell. -> » Another important object is to provide for printing with an element including a printing face formed by electrolytic deposition, which con sists in applying resilient means behind said ele ment while a print is being taken. 35 ' Another important object is to provide for backing a sheli-like printing plate with resilient material, suchas rubber, to improve the print ing characteristics of the plate wherein the re silient material is hardened in certain areas to 40 a greater degree than in other areas whereby to afford greater support behind certain portions ot the plate; a further object being to harden the rubber by di?erentially curing the same. Another object is to accomplish the di?eren- 45 ‘ a suitable adhesive in accordance with the design tial curing of the rubber by applying a medium ', oi'the printing ‘plate, dusting the printingsheet adopted to accelerate vulcanization in those areas with a .rubber vulcanizing mediumrsueh as 8111-‘ of the sheet where greater sti?'ness is required. printing pressure is applied. . . Another object is ‘to provide for mounting a ‘printing plate on a rubber blanket, which con 45 sists in printing a sheet oi‘uncured rubber with . 1* phur, mounting the plate on the sheet so that the ' -' "5o dusted'design onthe sheet registers with the cor responding design of the plate, and then vulcan _ izing the sheet in place so that the dusted por . tions, which are behind the lands orhigh spots of the plate, become harder than the adjacent _ 55 portions of the sheet as a result of the vulcaniz s ‘Another important object is to accomplish dif- V ie'rential hardness in the ?nished product by par- 50' tially pre-curing the rubber at the places where additional sti?’ness is required as by exposing the sheet to heat or other rays through a screen. ' Another important object is to accomplish dif ferential hardening of the rubber sheet by print- 55 2 2,188,981 ing the same with latex ink at the places where additional hardness is desired. Another important object is to provide a curved printing element having improved printing char acteristics. Numerous other objects, advantages, and in herent functions of the invention will become apparent as the same is more fully understood from the following description, which, taken in 10 connection with the accompanying drawing, dis closes a preferred embodiment of the invention. Referring to the drawing: Figure 1 is a perspective view of a relatively thin printing plate and resilient mounting layers, 15 the parts being shown in exploded or disassem bled relationship; ' Figure 2 is a perspective view of a printing plate mounted in accordance with my present invention; 20 - . Figure 3 is a vertical section taken substantially along the line 3—3 in Figure 2 ; and Figure 4 is a similar section illustrating a modi ?ed form of the invention. It has long been apparent that the most satis factory printing surface for letter press and other commercial printing is provided by the electro lytically deposited copper shell commonly used in the fabrication of electrotypes. The copper shell is comparatively thin and ?exible and re 30 quires support means to maintain the same ?rmly in place in order that the same may be used as a printing element. Such a shell is ordinarily ?nished by backing the same with a layer of usually metallic material, such as lead or a suit 35 able alloy, after which the electrotype is ?nished by bringing all of the high spots of the plate into a common plane, which is exactly parallel with the back of the electrotype. My present invention relates more especially 40 to improvements in the backing of shell-like ele ments in the provision of electrotypes and, in general, comprises the application of a resilient backing on the shell to the end that the printing surface of the same is rendered self-aligning dur ing the printing operation, whereby the ?nishing of the electrotype to bring all of the high spots of its printing surface into alignment does not require particular accuracy, care, or skill so that the labor and cost of providing a mounted print ing element in accordance with my present in vention is considerably reduced. I accomplish'these advantages by backing the thin printing element having a certain degree of ?exibility and having the design to be printed formed in the face of the plate. I contemplate particularly an electrolytically formed shell of the character commonly used in the fabrication of electrotypes. The parts are assembled by placing the plate ll face down on a flat surface, 10 such as is provided by a smooth steel plate. The back of the plate, if desired, may be coated with a suitable adhesive, the main function of which is to prevent corrosion of the plate during the curing of the rubber layers. The rubber layer 15 l5, which remains resilient after vulcanization, is placed upon the back of the plate II, and the fabric sheet iii, if used, is superposed upon the sheet I5. Finally, the rubber sheet H, which becomes hard after vulcanizing, is assembled in a stack. The steel support plate may then be placed in a suitable press having a heated head. This head is then lowered into contact with the sheet ll, so that the rubber of both layers l5 and I1 becomes heated and softens to a degree such that the material of the layer l5 oozes into all of the interstices and depressions in the back of the plate if. The two sheets of rubber also become fused together with the fabric I8 therebetween. The function of the fabric is simply to lend 30 strength and rigidity in the ?nal structure. I may substitute, for the layer II, a layer of any material which may be adhered to the layer l5 during the vulcanization of said layer l5 and which becomes or remains hard after vulcaniza tion is completed. For example, the layer l1 may comprise a metal plate if desired. After the layer l5 has softened, the heated head of the press is again lowered to squeeze the parts together. to the exact desired thickness of the ?nal assembly, and the application of heat is continued until the rubber becomes cured or vul canized. After that, the press is cooled. The heating and cooling of the press may best be accomplished by injecting steam into the head 45 during the vulcanizing process and then directing cold water into the head in order to cool the same and the rubber. With such an arrangement, but a few moments will be required to properly cool the assembly. - The plate may then be removed and its edges trimmed, as with a saw. then ready for proo?ng. No ?nishing is required, rubber, in order to obtain a printing element having all of the qualities of an electrotype and, in addition, the advantages of a resilient back ing,.by means of which the printed impression is of more uniform intensity throughout the area of the element due to the fact that a resilient back as the plate is ?nished to correct thickness in the press and possesses all of the ?nished qualities of an electrotype, since the high spots or lands are in type high relationship with respect to the rear a tri?e too high to yield during the printing op eration and come into alignment with the other lands of the element. The yielding character of the backing, moreover, permits the edges of the lands, which, in an electrotype, tend to print more heavily than the land ‘portions within the edges, to yield and thus eliminate any tendency toward “edge printing”. ' To illustrate my invention, I have shown on the drawing a- printing plate H mounted on a resil ient backing l3, comprisingva sheet of special vulcanizing rubber I! which retains its resilience after being vulcanized, and‘a second rubber sheet I‘! adapted to become hard and rigid upon vul 75 canization. If desired, a sheet of woven fabric 60 The mounted plate is printing plate with resilient , material, such as ing will permit those parts of the plate which are 7 I! may be interposed between the rubber sheets l5 and I1. The plate H may, of course, be any relatively most surface of the rubber layers. Except for proper line-up in the press, no make-ready is ‘ necessary, which results in cutting the idle press 60 time in half. In addition, printing presses of the character having reciprocating beds may be op erated at higher speed when carrying the rubber backed printing plates made in accordance with my present invention, because of the greatly re duced total weight carried in the press, as com pared with the weight carried by the press if loaded with electrotypes backed with metal in accordance with prevailing practice.v ' ' If desired, a suitable rubber cement may be 70 applied to the back of the shell ll before the layer I5 is assembled thereon, and cement may also be utilized between the layers II, II, and II, if desired. I contemplate also the application of the layer I! as a solution of latex painted, I 3 2,188,981 sprayed, or otherwise applied directly on the back of the shell ll. _ 1 I may also substitute resilient material other than rubber for the layer l5 and any suitable resilient material that can be adhered to the back of the shell may be utilized for this purpose. I particularly contemplate the use of resilient spongy material, which may be made by mixing flour of lead, or of a. selected alloy of lead, with tin and/or zinc and/or antimony with a quan tity of latex so that the metallic ?our is uni formly distributed throughout the latex. The accordance with the teachings of my present in vention as a part of the mounting of the printing element ll on'the resilient backing l5. When it is desired to cause any part of the plate to provide for increased impression in any part of the plate as mounted, the face of the shell II, at the places where increased-impression is de sired, is treated with a suitable adhesive ink and an impression made upon the underside of the sheet I5, as at 29, before the same is assembled 10 in stacked position on the plate. The printed surface of the rubber sheet is then dusted with sulphur or other vuleanizing medium and the surplus removed so that thevsheet l5 contains a metal is selected so that its melting point is lower than a maximum temperature permissible in vulcanizing the latex. The solution is applied ' layer of sulphur adhering thereto in such a posi 15 as a layer to the back of the shell and the coated tion that when assembled on the back of the plate II, the treated areas of the sheet l5 register shell placed in a vulcanizing press, which is oper ated at a temperature such that the latex is with those portions of the plate II at which in cured during‘the vulcanizing process and the creased impression is desired. The layer " may metallic ?our is also fused so that, after cooling, then be applied and the assembly cured in a 20. ' a spongelike metallic skeleton frame is formed press, as heretofore described. giriilughout the cured rubber layer behind the e . ' I have found that vulcanizing temperatures of ' from 300° centigrade upwards are desirable be cause this range of temperatures permits the use of any'well known alloy of lead, tin, zinc or anti mony. I have also found that by using a mix ture of tin and lead foil in equal parts and vul canizing at a temperature as high as 390° centi grade, an excellent backing is produced. These examples are given by way of illustration only and are not intended to limit the scope of my invention. , It is desirable to select a metal or an alloy having a melting point somewhat below the tem perature applied to the mixture in vulcanizing the latex in order that the metallic conduit may 'iuse at vulcanizing temperatures and form the spongy metallic mass. The selected metal should have a melting point considerably above the tem peratures to which the electrotype is submitted in the printing press since it is undesirable to have the spongy mass soften during the printing operation. There are, however, many alloys hav ing suitable characteristics with respect to melt ing temperatures which may be selected for the purpose, but I prefer to employ lead or suitable alloys of lead; with tin and/ or zinc' and antimony may be added to improve the character of the alloy. It will be understood that the resilient metal and rubber material may be substituted for either or both of the layers l5 and I1. Rubber-backed printing elements may be made ?at, or curved to ?t rotary presses, the same procedure being followed in the fabrication of curved plates as heretofore described, except that the'plate and rubber layers are assembled, com pressed,‘ and cured between cooperating curved surfaces of suitable shape. My present‘ invention, of course, applies to printing plates for reproducing type 2| as well as pictures or illustrations 2!. In order to properly print illustrations, it is desirable to provide ‘for greater impression on the solids or high spots 25 than on the low spots or high lights 21. This is usually accomplished on a letter press by means of overlays under the tympan. However, in other ‘ presses, and particularly in multi-color presses, During the curing operation, the sulphur treat ed portions of the layer l5 become relatively harder, as at_3l, than the remaining portions of * said layer, so that,'in the ?nished element, those 25 portions of the plate ii, in which increased im pression is desired, are relatively more ?rmly backed than are the remaining portions of the plate. When a printing impression isv made, the more ?rmly backed portions of the plate provide 30 increased impression in the corresponding areas of the resulting print. ‘ _ I may also provide for backing up certain por tions of the shell more ?rmly otherwise than by differentially vulcanizing said parts with sulphur 35 as a vulcanizing agent. For example, I may apply additional strips or patches of relatively hard rubber behind the parts of the shell re quiring additional backing ,before. the layer I5 is applied, or I may partiallypre-cure the layer 40 ill by exposing the'same to heat or other rays through a suitable screen formed in accordance with the parts of the shell requiring the addi tional backing. In this way, those parts of the backing, which are to be assembled behind shell 45 parts requiring additional support, are given a preliminary partial curing so that, when vulcan ization is completed, such parts are relatively more ?rm than adjacent parts and will furnish the desired additional support. I'may accom- ' 50 plish the same result by inking the layer i5 with a suitable latexsolution providing accelerator means to speed up the vulcanizing process at the places where applied.‘ These expedients may, of course, be utilized where the layer I5 is applied 55 directly to the back of the shell H or may be employed in conjunction with an adhesive ap-' plied'between the shell II and the layer and also may be employed where the back of the shell is ' sprayed with latex before the layer I5 is applied. 60 I may also sti?fen the shell prior to the appli cation of the resilient layer "by spraying or otherwise applying a metallic backing 33 on the shell H as shown in Figure 4. Such a backing 33 may comprise an alloy of lead with zinc and/or 05 tin, or any one of said' metals and may be» ap plied to any desired depth- upon the back of the shell. I prefer,>however, to apply the material 33 on the shell to a depth suf?cient to rather more it is usually necessary, since several plates are than fill the hollows behind the high spots‘ or 70 required in‘ printing the same impression, to make lands 2| and 23. the necessary adjustment as a make-ready in ' - After the layer 33 has been applied, the backe the plate itself. This, under the requirements of shell may be finished in the usual manner to ' prevailing printing practice, ‘is a somewhat ex bring the high‘spots or lands into alignment on the printing surface of the plate. This process, . pensive proceeding, but may be accomplished in 4 2,133,981 _ however, may be greatly simpli?ed if the overall ‘ tions in registration whereby the resilience of the , thickness of the layer 33 is kept relatively small. layer corresponds throughout the area of the ele The ?nishing operation also need not necessarily ment with the character of the printing surface of said element. . be performed with great accuracy since the resil 4. The method of mounting a relatively thin $1 ient backing thereafter applied will permit the shell to print uniformly as heretofore described shell-like printing element on a backing compris without being carefully ?nished. ‘ ing a resilient layer of rubber, which comprises After the ?nishing operation has been com pleted, the back of the layer 33 may be shaved 10 down to make the same substantially ?at and parallel with the printing surfaces of the high spots or lands. After this, the resilient layer i5 may be applied. This layer may be of rubber or a resilient metallic material of the character 15 heretofore mentioned. The layer I5 may be ap plied in any of the modes heretofore described, that is to say, may be applied as a solution of latex, sprayed or otherwise applied, behind the layer 33 and then vulcanized. The layer I‘! may 20 be applied behind the layer l5, or may be omitted, if desired. Alternately, the layer l5 may simply comprise a suitable resilient cement applied to any desired or suitable thickness, and I have found that the layers l1 and 33 may be connected to 25 gether with a resilient layer l5 therebetween merely by coating the surface of each with latex, clamping the parts together and heating to vul canize the latex. ‘ It will be understood from the foregoing that 30 my invention broadly comprises the provision of a resilient blanket behind a printing element of the character mentioned and the invention is not nec essarily restricted to the particular mode of ap plying such a resilient blanket. On the contrary, the invention consists broadly in the provision of any resilient blanket behind the printing element or electrotype during the printing operation in order that the printing element may yield in or der that the resulting print may be uniform throughout its entire area. - It is thought that the invention and numerous of its attendant advantages will be fully under stood from the foregoing description, and it is obvious that numerous changes may be made in the form, construction, and arrangement of the various parts, without departing from the spirit or scope of my invention and without sacri?cing any of its attendant advantages, the forms here in described being simply selected embodiments for the purpose of illustrating the invention. Having thus described my invention, what I printing the rubber layer in uncured condition with an adhesive medium in accordance with the design on the printing surface of said element, thereafter dusting upon the printed surface of the layer a curing medium adapted to control the resilience of the layer and thereafter curing the layer and mounting the plate thereon in position such that the corresponding portions of the ele ment and of the cured layer are in registration. 5. The method of mounting a relatively thin shell-like element, which consists in applying a resilient backing to the element and then dif ferentially hardening the backing opposite var in ious localized areas of the element to a rela tively greater degree than opposite the remaining areas and applying a support of uniform resil ience behind the differentially hardened backing. 6. As a new article of manufacture, a. unitary PS printing member comprising a thin printing ele ment, a backing of resilient material secured to said printing element, and a substantially non resilient ?lling layer between the backing and the printing element, said ?lling layer entering and ?lling the depressions on the back of the printing element. '7. A unitary printing member as set forth in claim 6, wherein the ?lling layer comprises a metallic material applied to the back of the print ing element and shaved to provide a flat surface to receive the resilient backing. 8. As a new article of manufacture, a printing member comprising a relatively thin element hav ing a printing surface, certain areas of said sur face requiring more printing pressure than other areas, a backing for said element comprising a yielding layer of resilient rubber, and a layer of relatively less resilient rubber behind the yield ing layer. 9. As a new article of manufacture, a. printing member comprising a relatively thin. shell-like metallic element having a printing surface on one side, certain areas of said surface requiring more printing pressure to print evenly than other areas, and a resilient backing secured on the other side claim as new and desire to secure by Letters Patent is as follows: 1. The method of mounting a relatively thin of the element, said backing providing yielding support of less resiliency behind the areas of the shell-like printing element, which consists in ap pressure. printing surface requiring increased printing plying a resilient backing to the element and 10. As a new article of manufacture, a. printing then hardening the backing opposite various member comprising a relatively thin, shell-like localized areas of the elementv to a relatively metallic element provided with a printing sur greater degree than opposite the remaining areas. 2. The method of mounting a relatively thin face on one side, certain areas of said surface re shell-like printing element on a backing com than other areas of said surface, and a. backing quiring more printing pressure to print evenly prising a resilient layer, which consists in treat secured to the other side of the element, said backing being adapted to provide relatively firm ing the layer in order to alter its resilience in ac cordance with the impression-making surface of support behind the areas of the printing surface the element and then mounting thev element on requiring increased printing pressure andrela the treated layer so that the corresponding por tively more yielding support behind the areas of tions of the element and layer are in registration. said surface requiring less printing pressure. 3. The method of mounting a relatively thin 11. As a new‘article of manufacture, a printing shell-like printing element on a backing com ‘member comprising a relatively thin shell-like element having a metallic printing surface on one prising a resilient layer of rubber, which com 71 70 prises printing the layer with a. substance adapt side, certain areas on said surface requiring more printing pressure to print evenly than other areas , ed to alter the resilience of said layer in accord ance with the design on the printing surface of on said surface, and a backing comprising a layer said element and then mounting the element on of rubber vulcanized differentially in different the printed layer with their corresponding por localities, whereby certain localized areas under 2,188,981 lying the areas of said printing'surface requiring more printing pressure are relatively less resilient than other areas in the layer. 12. As a new article of manufacture, a unitary 5 ment but thicker'than said element, adapted to force said ?exible printing surface, under print ing pressure into intimate and even contact with a surface to be printed upon, not co-planar with printing member adapted to be used in letterpress said printing surface, by locally bending said ele or relief printing, comprising a relatively thin and ?exible metallic element having a printing sur face, a backing therefor of resilient material, of said backing to said metallic element. substantially the same area as said metallic ele ment to conform to said surface to be printed upon, and a ?lm of adhesive material securing ~ PHILIP A. FRAZIER.