USRE11819E - Printing-surface - Google Patents

Description

UNITED STATE PATENT OFrIoE.

CLAUDE A. O. ROSELL, OF NEW YORK, Y., ASSIGNOR TO THE AMERICAN LITIIOGRAPHIC COMPANY, OF NEW YORK SPECIFICATION forming part of Reissued,Lettersiiiatentgnzp. lg1. ,8;lfi, dated l9, Original No. 637,554, dated November 21, 1399. Application for reissue filed De c ehiberflZ, IBQQi Serial. No. 741,345:-

To all whom it may concern..-

Be it known that I, CLAUDE A. O. ROS-ELL, a citizen of the United States, and a resident of the city, county, and State of New York, have invented certain new and useful Improvements in Printing-Surfaces,of which the followi'nglis a specification.

' The invention relates to planographic print- "ing, and has especial reference to the charactor of the printing form or device to be used in such planographic printing; and it consists of the improved apparatus herein shown and claimed.

The invention has especialapplicability and-usefulness in connection with rounded or cylindrical printing-forms and will be more especially described in that connection. More particularly it has in view the repeated renewal of a given planographic-printing form or device with a new fresh printing-surother zinc iselectrolytica lly depositedupon a cylinder of copper and the printing is effected from the zinc surfaces thus deposited. In the former case the mechanical incidents and difficulties accompanying-the application and holding of the flexible sheets, as well as the expense of preparing the faces of those sheets for printing purposes, as by sand-blasting, have constituted serious obstaclesin the way of extended use. In the latter case-after the edition has been printed the effort has been made to remove the zinc printing-sur face by means of nitric acid; but the nitric acid in this operation has the disadvantage of removing also a notable amount of copper, thereby gradually diminishing the diameter of thecopper cylinder and, moreover, diminishing it unevenly, a feature which interferes the press. "the aluminium is] preferably burnished.

with and prevents the uniform taking of ink and. water'from the ink and water rollers, re' spectively,-and the uniform printing of the same. Moreover, any notable diminution in the diameter of the printing-cylinder would interfere withand prevent the proper codperation of that cylinder with the other parts of the printing-press, and register would be gradually interfered with and finallyv rendered impossible to obtain without the recon- These difiiculstruction of the entire press.

ties are overcome in the following manner:

In the preferred form of my invention I pre-.

pare a cylinder of aluminium sufficiently strong.tostand the pressure of printing or 2.

cylindrical shell, of aluminium supported upon an interior mandrel of iron or copper or any suitable metallic base the outer surface of which is aluminium. This cylinderorbase having this'outer surface of aluminium is finished with great accuracy and care with respect to uniformity of surface, exactness of dimensions, &c. ,-al1 with reference to the ex act shape and sizeof printing-form desired in To increase its protective action,

Upon this surface I then deposit electrolytically an outer coating or face of zinc in such way as, while causing such zinc surface to be anintegral part of the composite form,

shall at the same time render itsufliciently porous and of the necessary surface charab- I ter to adapt it to act as a lithographic or planographic printing surface.- In orderto achieve this result and .to secure a zinc surface that will properly adhere to. or integrate with the aluminium surface and be of the proper porous character 'for planogra-phic printing-,1 electrodeposit the zinc from a solution of a zinc salt and an ammonium salt made gbasic by the addition of ammonia or from ajsol'ution of a zinc salt and aluminium salt andan ammonium salt made basicby the addition of ammonia. For this purpose a solutionef zinc sulfate, aluminium sulfate, ammonium sulfate, and ammonia has been found satisfac-.

tory. A solution containing three per cent. of p zinc sulfate and an equal amount ofaluminium sulfate and of ammonium sulfate will be found suitable. The deposit of the zinc should be m ade by a. low current. A- current strength roe ' square foot wouldjbe suitable.

of from one-quarterto one-half an ampere per In the above solutions the ammonia should not be added in quantity suflicient to form a permanent precipitate. If to asolution of a zinc salt ammonia is added until the-solution becomes alkaline to litmus-paper and the precipitate at first formed is redissolved, the electrodeposited zinc, will not adhere to the aluminium plate. The above-described process by which an electrolytically-deposited surface of zinc upon aluminium is obtained is not specifically claimed in this .application, but is reserved for and forms the subject-matter of a separate application filed by 'me in the United States Patent Office on the 17th day of May,

1899, Serial No. 717,237. After the pianographic zinc' surface has been suitably applied the plate is at once ready to receive a transfer after the lithographic manner and to be suitably developed into a printing-surface by the process of etching familiar in that artas, for example, by the use of a weak solution dampening devices.

of gum-arable and phosphoric acidand to be thereupon used as a plauographic-printing surface in a press containing both inking and After the use of the printing-form for printing purposes and the removal of the ink of the transfer in the usual way, as with turpentine, &c., the entire ,z inc coating is removed by means of suitable dilute nitric acid. By this operation .the aluminium protective surface will be exposed, but without being in anyway substantially alfected or modified or itself removed and will be immediately ready to receive a second deposit of zinc for a second printing operation or edition. Care should be taken not to employ nitric acid that is very strong, for such acid would have some slight action upon the aluminium, although even then the action would be insignificant as compared with the action upon copper, and so would be practically'negligible; Dilute nitric acid will be found suitable for removing'thezinc, and it will have substantially no action upon the aluminium, so that the aluminium cylinder will last indefinitelylong. Thus the printingform consists of an outer coating or face-of electrolytically deposited zincjand suitable for planographic printing, butadapted to be .wholly'removed by a suitable reagent after the printing of one job is finished, and a base of suitable material integral with the outer printing-coating, the base having a protective face or coating of aluminium underlying the printing-coating. In this way and by the application of an even printing-surface otiuniform and predetermined thickness the resulting printing form or device as -a whole is always and permanently of the same shape and size, thus-fitting it to cooperate permanently with the other parts of the printing-press. Moreover, as all the wear of the printing .operation is on the outer coating or face, which is wholly removed and a new fresh coating or face applied for each new printing job, a

printing-cylinder prepared as above described is practically indestructible.

Although specifically described'with refer euce to cylinder-printing, where the invention has peculiar usefulness and advantages,- and especially iuconnectiouwith multicolor cylinder printing, it -nevert heless applies equally well to printing from flat or curve;

. ally-deposited?zintfihaidsu rface having a design npo'n it suitably developed and being v thereby adapted to print 1ithographically,the f surface being alsoadapted to ,be thereafter 9o wholly removed by a suitable reagent not acting on the protective coating, the base, the protective coating and the printing-surface being all integrallyunited together substantially as described. I r

2 A lithQ'graphic-printin g. form composed of a metallic base, a burnished protective coating thereon of aluminium, the base with said protective coating being as a whole of non-varying shape and dimensions, thus'perloo manntly adapting the printing-form as a whole to the cobpera'ting parts of the press, and an outer planographic-printing surface of clectrolyLically-deposited zinc,said 'surface having a design upon it suitably devel- 105 oped and being thereby adapted to printlithographically,the surface being also adapt- ,1 ed to be thereafter wholly removed byasuitable reagent not acting on theprotective", coating, the base, the protective coating and; no the printiugsurface being all integrally united together substantially as described.

3. A cylindrical lithographic-printing formcomposed of a metallic base, a protective coating thereon of aluminium, the base with" n 4. A cylindrical lithographic-printing form 13o composed ofa metallic base,'a burnished pro-L tective coating thereonof alumini-um, the base with said protective coating being as a whole of non-varying shape and dimensions, thus permanently adapting the printingform as a whole to the cooperating parts of the press, and an outer planographic-printing surface of electrolytically-deposited zinc, said su rface having a design upon it suitably developed and being thereby adapted to print lithographically, the surface being also adapted to be thereafter wholly removed by a suitable reagent not acting on theprotective coating, the base, the protective coating and the printing surface being all integrally united tokgether substantially as described.

5. A cylindrical lithographic-printin g form 1 composed of a metallic base of copper, a protective coating thereon of aluminiu m ,the base with said protective coating being as a whole of uon-varying shape and dimensions, thus permanently adapting the printing-form as a whole to the cooperating parts of the press, and an outer I planographicprinting surface of electrolytically-deposited zinc, said surface having a design upon it suitably developed and being thereby adapted to print lithographically, the surface being also adapted to be thereafter wholly removed by a suitable reagent not acting on the protective coating, the base, the protectivecoating and the printing surface being all integrally united together substantially as described.

6. A cylindrical lithographic-printin g fornr T composed of a metallic base of copper, a burnished protective coating'thereon of alumini-- um, the base with said protective coating being as a whole of non-varying shape and diinen'sions,, thus permanently adapting the printing-form as a whole to the cooperating parts of the press, and an outer planographicprinting surface of electrolytically-deposited zinc, said surfacehaving a design upon it suitably developed and being thereby adapted to print lithographically, the surface being also-adapted to be thereafter wholly removed by a suitable reagent not acting on the protective coating, the base, theprotective coatingand the printing-surface being. all inte= grally united'together substantially as described. 1

7. A lithographieprinting form composed l of ametallic base, a protective coating there- 50 on of aluminium, the base with said protectlve coating being as a whole of non-varying shape and dimensions, .thus permanently adapting the printing-form as a whole to the cooperating parts of the press, and an outer planographic-printing surface having a design upon it suitablydeveloped and being thereby adapted to print lithographically, the surface being also adapted-to be thereafter wholly removed by a suitable reagent not acting on the protective coating, the base, the"- protective coating and theprinting-surface being all integrally united together substantially as described.

'8. A lithographic-printing form composed of a metallic base, a protective coating thereon of aluminium, the base with said protective coating being as a whole of non-varying shape and dimensions, thus permanently adapting the printing-form as a whole to the cooperating parts of the press, and an outer planographiceprinting surface of electrolytically-deposited metal, said surface having a design upon it suitably developed and being thereby adapted to print lithographically, the

- surface being also adapted to be thereafter wholly removed by a suitable reagent not acting on the protectir e coating, the base, the protective coating and the printing-surface being all integrally united together substan tially as described.

9. A lithographic-printing form comprising an aluminium protective face of non-varying shape and an outer planographic-printingsurface, said surface having a design upon it suitably developed and being thereby adapted to print lithographically, said surface being also adapted to be thereafter wholly re- Y moved by a suitable reagent not acting on the protective face, the protective face and the printing-surface being integrallyunited together, substantially as described.

10. A lithographic-printing form comprising an aluminium protective face of non-varying shape and an outer planographicsprinting surface of electrolytically deposited metal, said surface having a design upon it suitably developed and being thereby adapted to print lithographically, said surface being also adapted to be thereafter wholly re: moved by a suitable reagent not acting on the protective face, the protective face and the printing-surface being integrally united together, substantially as described.

1 1'. 'A lithographic-printing form comprising an aluminium protective face of non-varying shape and an outer planographic-printlng surface of electrolytically-deposited zinc, said surface having a design upon it suitably developed and being thereby adapted to print lithographically, said surface being also adapted to be thereafter wholly removed by a suitable reagent not acting on the protective face, the protective face and the printingsurface being integrally united together, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CLAUDE A.. 0. ROSELL. Witnesses;

EDWIN SEGER, SIDN Y MANN.