Patented Feb. 14, 1939 ‘ 2,146,976

UNITED 7 STATES PATENT OFFICE 2,146,976 METHOD OF_ MAKING DUPLICATE COPIES George G. Neidicli, New York, N. Y. - No Drawing. Application February 23, 1937, Serial No. 127,169 10 Claims. (Cl. 41-315) This- invention relates to improvements in In still another process, use is made of a method methods of making duplicate copies, and more known to the art as spirit duplication. In this particularly to improvements in offset duplica process, a master. copy in strong soluble basic —tion methods of making'dupiicate copies of type anilin dyestuif is produced by typewriter, writ 5 grkitten. matter, hand written matter, and the ing or drawing, as in the case of the gelatin e. processes, except that the typewriting, writing, Heretofore several methods have been em or drawing is in mirror reverse. Ordinarily, ployed for producing copies of matter of the use is made of a special carbon paper whose foregoing character, all of which methods‘re active surface is placed in contact with one side 10 suit in the production of duplicate copies of of the master sheet on which the original type master images, which copies are usually produced writing, writing, or drawing is imposed. When on paper contacted in some manner with a master the image to be reproduced is imposed on one having thereon an image of the work to be dupli surface of this master sheet, the other surface , cated, which master contains material quantities thereof, which is in contact with the carbon 15 of strong dyestuff adapted to be transferred to paper, acquires a deposit of the coating material the copies in the steps followed in the different _of the carbon paper according to the’ lines of processes. . impress on the blank surface thereof. Thus a -In one method, use is made of what is known mirror reverse copy of the matter to be repro to the art as a hectograph pan. In this method duced is formed on one surface of the master 20 a gelatin compound is disposed in a pan, A sheet by the transfer of the coating material normal master sheet is typewritten, written, or from the carbon paper to the master sheet. This drawn, with an ink strongly colored with basic mirror reverse copy is attached to the‘ drum of dyestu?, usually crystal violet, the master being a spirit duplicator and sheets of copy paper are usually in' the form of a sheet of paper or the fed thereto in succession. Means are provided 25 like. Crystal violet is ordinarily used since this for moistening the sheets of copy paper immedi 26 dyestuff is more powerful and is more quickly ately prior to their contact with the master sheet, soluble than other dyestuif. The master is laid and since the basic anilin dyestuif in. the com on the top surface of the gelatin compound in position on the master sheet is highly soluble. the pan and permitted to remain in contact with the moist surface of\the copy sheets when con so the surface thereof until the compound absorbs ' tactéd with the mirror reverse copy on the master 30 locally suf?cient of the dyestu? to produce at sheet cause the transfer of coloring- matter to least onehundred copies of the matter to be the "copy sheets. In this process, use may be reproduced. The absorption of dyestuff from made of any desired solvent, but preferably the the master is in’ accordance with the lines of solvent used is ordinarily more volatile than 35 the image on the master so that in veffect a mir water, the practice having been to make use of ror reverse copy of the matter to be reproduced alcohol, methanol, acetone, or other similar sol is formed in the compound. Sheets‘ of copy paper vents or combinations ofv solvents. By the use are then contacted with the surface of the com of such solvents, more copies can be produced pound, resulting in the transfer of su?icient dye from a single master, and the copies so produced ' “; stuff from the compound to the copy sheets as are sharper than those produced by the use of to produce copies of the matter desired. ~ water. Moreover, the copy so produced dries This principle has been further extended to almost immediately at normal temperature. a process in which the gelatin composition is , In the practice of all of the foregoing processes, _ V thickly coated on a backing sheet, usually as a certain faults are present which sérve to limit the 45 roll of considerable length fastened to the drum ‘use thereof: Since the processes have required of a two cylinder machine. The same procedure the use of dyestu?- which is highly water soluble,’ - for causing absorption of dyestuff‘ is followed it follows that the handling of the dyestuif in out so that the composition contains absorbed most instances results in stains both to the person ~- ' therein a mirror reverse copy of the original and the clothing of the user. _ For example, the in matter and the surface of the gelatin becomes .~moisture of the-hands of the user alone is suiii ' ’ a printing medium. Copy sheets are fed between cient to transfer material quantities of the dye the master cylinder (having the gelatin surface) stui’f to thehands, and consequently clothing also and a platen cylinder causing transfer of dye-v readily becomes stained, all of which is, highly stuff to the copy sheets and thereby producing undesirable. The ribbons, carbons, or ?uids I. legible copies of'the desired matter. ' which have been used all contain large quantities I‘; 2 2,140,970 .of basic dyestuffs,-such as crystal violet, rho; user since the material which is to be utilized damine, Victoria blue, or Victoria green, all of as color transfer material has of 'itself no ap which are water soluble ‘colors. It is evident, preciable color transfer value and is water in_ therefore, that any process which requires the soluble, but must be further treated to cause it handling of ribbons, carbon paper, or ink of this to acquire high color transfer value. character will produce the objectionable results Use of the present invention therefore can be before set forth. , made in duplicate processes involving the use An object of the present invention is to provide of gelatin, either in a pan or on a roll. In such new methods for producing duplicate copies, processes the normal image of the matter to 10 which methods are free from the objectionable beduplicated, if typewritten, can be made on results before described. _ a sheet of paper through the agency of a ribbon Another object of the invention is to provide of the character before described. ' The gelatin, methods of making duplicate copies, which meth either in the pan or on the roll, can be either ods involve the use of transfer‘material which in impregnated or the surface thereof washed with 15 itself and before further treatment possesses sub a dilute acid in aqueous solution; as for ex 15 stantially no objectionable color transfer value. ample, a ten per cent solution of lactic acid. Another object of the invention is to provide The acid, either on the surface of the gelatin, methods of producing duplicate copies wherein or impregnated therein serves to react with the master copies of the matter being reproduced areJ base of the dyestuff absorbed from the sheet of, 20 formed through the agency of matter having no paper, having the normal image thereon, to con 20 appreciable color transfer value and wherein such vert such base of the dyestuif into basic dyestuff. masters are subsequently treated to cause such Copies may then be'made in the usual manner. material to have high color transfer value. In the adaptation. of the present invention to In carrying out the foregoing and other objects spirit duplicating processes, again the normal 25 of the invention, the present invention contem steps followed in such processes are carried out 25 plates the use of material which in itself possesses with the exception that use is made of carbons, no appreciable color transfer value and which or of powdered ink, which have no appreciable material is of a character as to be insoluble in transfer value, but which must be subjected, to water.’ Consequently, this material may be han a reaction to acquire such transfer value._ A 30 dled in any manner required by the processes "Lmirror reverse copy of the matter to be dupli 80 hereinafter described withoutincurring the liabil cated is formed on a master sheet in any of > ity of staining the person or clothes of a user. the usual manners such as for example, by mak The basic anilin colors which have previously ing use ,of a coated .carbon containing the base been used ‘in connection with carbon paper and of the dyestuif combined with a suitable vehicle. 35 ribbons are in the ‘form of organic salts or esters A mirror reverse image of the matter to be 35 of‘ highly complicated organic radicals. The reproduced may be activated by a small amount present invention makes use of the desirable qual of a relatively weak acid in a number of ways, ities of these basic'dyestuifs without incurring the of which three are hereinafter set forth. undesirable qualities thereof. To this end, in 1. An activated sheet specially prepared is stead of using the basic colors themselves, use is made up of a sheet of paper coated with a satu- ~ made of the bases ofsuch basic colors such as the rated solution of solid .acid, "such as benzoic, in bases of crystal violet, methyl violet, rhodamine, a volatile solution such as alcohol. To such Victoria blue, Victoria green, Bismarck brown, solution is added an alcohol vsoluble gum such and aurarnine or combinations of these bases. as shellac, which diminishes the tendency of Bases of these basic dyestuffs can be manufac the acid to crystallize on the sheet. ., tured in 'any suitable manner either as an inter _ After the master sheet, having the image in mediate step in the normal production of the mirror reverse thereon, has been fastened to the basic dyestuffs, or as the result of processing basic drum of the spirit duplicator machine, and prior dyestuffs in solution. For example, when basic to the preparation of any copies therefrom, an dyestuif in solution is treated with dilute alkalies, activating sheet, or‘ a series of activating sheets, 50 as for example, sodium carbonate or sodium hy are fed slowly vthrough the machine. The sur drate, a precipitate of ‘water insoluble basic color face of the activating sheet is moistened by the base is formed which is the hydrate of the water , alcohol or other solvent of the duplicating ma bearing radical. Such precipitate may be?ltered chine, and' this moistened acid bearing surface 56 and dried, and the powder ‘so formed may readily is ?rmly pressed by- the machine against the be obtained on the market as crystal violet base, master image, thereby transferring sumcient acid rhodaminebase, etc. to the base ofthe'dyestuif in the master image As a further step in making possible the prac-' as to carry out the proper reaction to convert tice of the processes within the scope of this this base of the dyestuif into basic dyestuih The so invention, ribbons or carbons may be made which vresult of ‘this procedure is that the image on the 80 incorporate, instead of basic dyestu?', the base of master sheet is now soluble substantially as if such basic dyestuif which is combined with some originally made with /the objectionable carbons binding material or vehicle of a character which heretofore employed, and copies may be made in is substantially free from any acid solvent which the usual fashion. g ‘ would react with the base “of the basic .dyestuif to 2. The specially prepared activating sheets 65 convert it into basic dyestuff. Transfer material may be dispensed with and in lieu thereof any such. as ribbons and carbons so made‘form the acid soluble in or miscible with the solvent used subject-matter of my copending application S. No. in the duplicating machine may be/added to the 127,170, ?led February-=23, 1937, and accordingly, solvent in the tank of such machine. For this 70 illustrative examples, of the composition thereof purpose it has been found that the addition of 70 and claims “thereto have‘been incorporated in ten percent of lactic acid causes the solvent in such copending application. I ' the tank to have sufficient acidity as to carry out Ribbons or 'carbonsin' accordance with the the proper reactions. ' ‘ foregoing can be handled without incurring the When such a solution is used in the duplicator '. liability of staining the person or ‘clothing of a tank, the. practice of making copies is followed 75 2,140,970 3 out as before with these differences in operation. other suitable compound from which copies are The acidi?ed solution is supplied to the surface taken by dyeing the paper locally at such trans of the copy sheet in such minute but sumcient ferred image. The word “hectograp " is used to quantity as to provide sumcient acid to react with define devices employed in the above described the-matter of the master image to cause the hectographic process whether such devices be conversion of limited quantities of such matter simple pads containing the hectographic compo into the desiredbasic dyestuff.mThis conversion, sition or machines involving rolls or strips of sinn depending on the quantity of acidi?ed solution artype. ‘ > ~ supplied to the surface of the copy sheet, is more From the foregoing it will be seenthat the present invention provides methods of producing 10 1 0 or less of local nature, but eventually the entire quantity of material in the master image‘will duplicate copies by o?set duplication, which' be converted into the proper dyestu?. methods overcome the objection heretofore raised 3. In a still further method of performing the thereagainst due to the extreme solubility of the necessary chemical reaction, a master sheet hav coloring matter which renders the material. ‘necessarily used in connection with such offset 1 5 ing the image in mirror reverse thereon in water insoluble dyestu? is prepared as before, but prior duplication processes, objectionable due to stain to being attached to the duplicator machine, such ing of the users’ person or clothing. It is to be sheet is subjected to acid fumes. For example, ' understood that the invention is capable of modi a closed box may be provided, such box having ?cation beyond those examples heretofore set a felt bottom on which a few drops of acetic forth and accordingly the limitations to be im acid are placed. A sheet may be introduced posed thereupon are to be such only as are set into the box and permitted to remain therein forth in the following claims. for a su?icient length of time to permit the What is claimed is: acid fumes to accomplish the ‘desired reaction. 1. The method of preparing a master image In practice it has been found that about ?ve for use in offset duplication processes which com 25 minutes of such treatment will‘sufiice. prises forming a master image of material which The foregoing has been used to describe the in itself has no appreciable transfer color value and subsequently reacting with said material, a . present invention in the preferred form. How suitable reagent for converting said material into ever, there are other methods which may be utilized for securing the water insoluble image matter having a high transfer color value. 30' 2. The method of preparing a master sheet for on the master copy. One of such methods is to .use in, offset duplicating machines which com substitute an insoluble “acid" color for the color prises. forming a master image with water in base hereinbefore. described and to activate the master by the use of an organic chemical having soluble color material and submitting such image a basic reaction, preferably triethynol ammine to the action of a reagent capable of making such color material water soluble. . instead of the mild acid previously described. . 3. The method of preparing a master image Another method is to convey to the master, for hectographic processes WhiChg comprises preferably by ribbons or carbons, an image in forming a master image of water insoluble ma color material which is insoluble in water but terial, transferring .said material to the com which is soluble in a particular solvent more pound of the hectograph, and reacting with said volatile than water. In this event the chemical material while in said compound a reagent capa reaction before described is not required since the’ solvent for any spirit duplication is sumcient to ’ ble of converting such material into .water solu cause the transfer of the- coloring material; and ble matter having high transferable color value. _-4. The method of preparing _a master sheet 45. in the‘ event of the gelatin processes, such solvent for hectographic processes which comprises can be incorporated in the gelatin. A variety of forming a master image containing a basic color such dyestuffs are being made and sold by various base and reacting with said base an acid while' dye makers and these dyestuffs particularly are said base is incorporated in the hectographic‘ those insoluble in water but soluble in alcohol‘ composition. 50 and acetone respectively. These special dyestuffs, a; - '5. The method of preparing a master image while not preferred in the practice of the present.v for use in offset duplication processes which com. invention, may be used with satisfactory results. . _. prises forming a master image of water-insoluble As a still further embodiment of the invention“. that ribbons or carbons may» ' material which in itself has no appreciable trans it is contemplated for color value and subsequently reacting with 55 be manufactured to contain a material which will‘ said material, 'a suitable reagent for converting react with another material contained'in either the spirit solvent or the hectograph gelatin mass said material into water-soluble matter having to develop color. For example, these steps can ‘a- high transfer color value. 6. The method of preparing a mirror reverse - be-followed for obtaining the reaction between 60 gallotannic acid, and iron'salts to produce black image for use in spirit duplicators which com coloring material and also the reaction' between prises forming a master image from color ma ferrocyanide and ferricyanide for the develop terial insoluble in water, and subjecting the ma terial of said image to a reagent to convert such ment of blue coloring matter. > ' material into water soluble matter. _ The term "offset duplication processes" in this 65 specification and'in the claims is'used to'de?ne "-7: The method of preparing a master image 65. processes ‘described for hectographic processes which comprises a the types of duplication forming a master image of water insoluble ma hereinbefore which-have the common ‘element terial and transferring the image material to the that the desired image is produced by dyeing the compound of the hectograph having associated copy locally as distinguished from lithography ‘therewith a reagent capable‘ of converting such 70 0 (direct or oifset) printing, mimecgraphing, or multigraphing,_all of which involve the depodt of water insoluble material to water soluble or transferable color matter. a pigment on the copy. The term"‘hectographic 8. The method of preparing a mirror reverse process" has also been used herein to define any ' image for use in spirit duplicators which com process in whioh‘the normal image is transferred prises forming a master image containing basic 75 75 in mirror reverse to the surface of a gelatin or ' 4 2,146,976 color base insoluble in water, and contacting with machinesand being supplied to copy sheets pass said image a reagent carrying prepared sheet to ing through the machines. - convert, said basic color base into basic color mat 10. The method of preparing a master image ter. . , - for hectographic processes which comprises 5 9. The method of preparing a mirror reverse forming a master image of material which in _ image for use in spirit duplicating machines itself has no appreciable transfer color value ab which comprises forming‘ a master image with sorbing said material into a hectograph com water insoluble color material and submitting pound and subjecting the absorbed material to a such image to the action of a reagent capable oi.’ reagent to convert it into matter having high 10 making such color material'water soluble, said re transfer color value. ' agent being included in the liquid supply for the GEORGE G. NEIDICE.