US3122997A

US3122997A - Figure

Info

Publication number: US3122997A
Authority: US
Current assignee: White Consolidated Industries Inc
Priority date: 1958-04-04
Publication date: 1964-03-03
Anticipated expiration: 1981-03-03
Also published as: BE577338A; NL237781A; FR1228426A

Description

w. A. RAczYNsKl ETAL Original Filed April 4, 1958 METHOD oF PREPARING COPIES INCLUDING MASTERS Z L l March 3,1964

United States Patent O 3,122 9157 ME'IEUE) 0F PREPARG CPES INCLUBING MASTERS The invention relates to methods of preparing copies from originals and includes methods of preparing masters for use in duplicating. More particularly, the invention relates to methods for preparing masters of solvent duplicating processes, masters or mats suitable for odset and direct planographic or lithographie processes, and masters for use in the mimeograph process, as well as methods oi producing `facsimile copies.

The solvent type duplicating processes include hectograph, spirit process, gelatin and chemical reaction types oi duplicating.

In the hectograph-gelatin process, characters or designs are impressed on a sheet of paper with a hectograph ink composed of a waxy material containing a water and alcohol soluble dye, this paper then being contacted with a gelatin pad or roll whereby the characters or desicns ar transferred in reverse to the surface of the gelatin. `Copies are made by successively applying copy paper to this pad or roll.

in the spirit duplicating process, a master sheet having characters or designs in mirror image thereon and composed or a waxy material containing an alcohol soluble dye is placed on the drum of a duplicating machine and contacted with a succession of copy papers previously moistened with a volatile solvent such as alcohol whereby portions of the mirror image are transferred to the master paper and characters or designs are reproduced on the copy papers.

ln the chemical reaction type duplicating process, characters or designs on the master sheet are composed of a waxy material containing a chemical reagent which reacts with a chemical in or on the copy paper when the copy paper is moistened with a liquid containing a solvent for the chemical agents or their reaction products. The chemical reagents may alternatively be in the moistening liquid instead of in the paper.

ln the mimeograph type duplicating process, a stencil master is created by striking the characters or designs to be reproduced through a sheet of fibrous material, generally coated with a waxy substance, so that ink or other marking material may pass through the impressions thus made. The stencil master is then placed on the drum of a mirneograph duplicating machine and reproduced by means of ink passing through the stencil master in contact with copy sheets.

in the planographic or lithographic process of duplication, the master or mat consists of a hydrophylic base material having thereon characters or designs cornposed essentially oi a greasy material such as a fat or wax. The imaged master or mat is thus diiierentially receptive for water in the hydrophylic area and for a greasy or oily ink in the image area which contains the oleaginous lithographie material. As a result, on mounting such a master or mat on a suitable duplicator, which may be an oliset type of duplicator or a direct lithographie type duplicator, moisture and ink can be repeatedly applied to the mat and removed to produce a multiple series of copies.

All of the above processes have the disadvantage that hitherto there has been no simple and inexpensive process for producing facsimile masters from already prepared originals. The process commonly used at pres- ICC ent for preparing a master from an original is to draw the original on the master, to use type similar to that on the original if the original has been typed or printed, or to use art engraved plate which has been made to conform to the original design. Hitherto there has been no simple and inexpensive method for the facsimile duplication of an original which is particularly desirable for duplicating letterheads on a letter, signatures, time stamps, and the like.

In the production of facsimile copy, resort is usually made to a photocopy device or to a heat sensitive copying device such as Thermofax copy supplied by Minnesota Mining and Manufacturing Company.

ln the case of facsimile copies, the photocopy method of reproduction is not only expensive, but has the additional disadvantage of producing wet copies which take a considerable period of time to dry. ln the case oi the rhermofax process, the copy still retains heat sensitive areas which in time degenerate due to heat or which may degenerate entirely if placed in close proximity to a source of heat, such as a radiator or even intensive sunlight.

An object of this invention is to provide a method for the facsimile preparation of a master which will give duplication of an original with an exactitude such as can be obtained by a photographic or photostating process and with use of a duplicating machine such as the spirit process, hectograph and planograph machines.

Another object of this invention is to provide a method for preparing a number of masters readily and conveniently from the sarne original copy and thus to increase the number of copies which may be achieved by the use of the spirit, or related duplicating processes.

Another object of this invention is to provide a meti od for preparing expeditiously and conveniently a facsimile master from a typed, printed, offset printed, written, or otherwise prepared original having differential areas of heat absorption or heat transmission.

A further object of this invention is to prepare expeditiously and economically a direct image master for use in the offset lithographie process or direct lithographie process from the original copy that heretofore had to be processed in a roundabout, laborious method.

Another object is to provide a method of mal-:ing several direct image mats or masters in facsimile form from one original copy.

Another object is to provide a thermal method of making facsimile stencil masters which can be used similarly to a photographic negative for making imaged presensitized lithographic plates.

Still another object of this invention is to provide a thermal method of making mirneograph masters from stencils.

Another object of this invention is to provide a method for the making of facsmile copies from an original.

Still another object of this invention is to provide a thermal method of making facsimile copies as well as masters whereby the light from the source does not pass through the master or original copy, commonly referred to as reex.

Other objects and advantages of the invention will become apparent as the following detailed description progresses, reference being lmade to the accompanying drawings wherein:

FIGURE l shows a diagrammatic elevation of an apparatus for carrying out the process of this invention;

FIGURE 2 is a perspective View showing a master made in accordance with one embodiment of the process;

FIGURE 3 is a section taken along the line 3 3 of FiGURE 2;

FIGURE 4 is a perspective View of another form of the invention; and

FIGURE 5 is a section taken along the line 5 5 of FIGURE 4.

1n accordance with this invention, an origmal copy 1 such as a typewritten sheet of paper with or without letterhead is placed in contact with a heat owable coating 4 of a base sheet 5. In one embodiment of the invention, the back, non-image side of the copy sheet 1 is placed in contact with the coating 4. An infra red generating source, such as a heat lamp 10, is shone on the typed and printed side of the copy paper while the copy sheet and coating are in close contact, whereby the black characters 2 absorb infra-red radiation and transmit a heat image to the portions directly in contact and the light portions .retlect infra-red radiations without substantial conversion to heat and transmission to the coating. The amount of eat from the infra red source is regulated so that the heat transmitted to the coating through the black characters gives a temperature in the immediate underlying composition such that the composition is below its melting point and at or above its flow point at the Contact pressure. On separating the two sheets, the back side of the copy 1 contains the reverse image 2a of the matter on the front or image side of the copy sheet and is suitable for use as a duplicating master, the type of master depending upon the composition of the coating. This method of making the original into a master is referred to hereinafter as a iirst generation master.

The process in which the temperature of the coating composition is below its melting point but at or above its iiow point is our preferred process. This makes possible the carrying out of the process with infra red absorptive coating compositions containing infra red absorptive dyes, which is a particular advantage in the production of hectograph and spirit process masters wherein the coating composition contains the infra red absorptive crystal violet or methyl violet dyes. Crystal violet and methyl violet dyes are the preferred dyes for spirit or hectograph cornpositions, due to their intense dye strength, commercial availability, solubility, and other characteristics which have made these dyes standard for years in this phase of the duplicating industry.

This procedure of regulating the temperature so that the coating composition is below its melting point, that is, below the temperature in which all components are liquid, also allows us to carry out the process eiiiciently without the necessity of having temperatures of above 150 F. on the black characters. We can have a temperature of 125 F. on the black characters and can use a wax coating composition which is partially but not completely liquid at a temperature slightly above 125 F. This makes possible the use of relatively common and inexpensive waxes for the coating composition. This also makes it possible to use a minimum of infra red energy to obtain satisfactory preparation of masters or copy which results in a more feasible and economical apparatus, the usage of lower currents and minimizing the amount of scumming that can occur with infra red absorptive compositions.

It is possible to carry out the process by bringing the temperature of the coating composition immediately underlying the characters to a temperature at which all portions of the coating composition are liquid. This procedure, however, does not result in such sharp character reproduction and makes it more diicult to obtain satisfactory results when high infra red absorbent pigments are present in the coating composition because the use of infra red absorbent material decreases the temperature differential between the character part and adjacent portions ofthe coating composition and the excess temperature required to have a completely liquid phase enhances the chances of migration of the liquid beyond the outlines of the characters. In our preferred process, the temperature of the` coating composition directly underlying the characters is preferably such that some molten wax is presen-t, so as to promote wetting and consequent transfer, but there are also some solid constituents present, so

sheet by the wetting action of the liquid. This at least partially accounts for the clear-cut sharp characters produced in our process.

It has also been found that transfer occurs best at a temperature range between F. and 140 F., as the maximum temperature of the transfer coating composition, and preferably at temperatures of F. and 138 F. This gives a low temperature differential between the temperature of the characters of the original and the temperature of the underlying transfer composition, instead of the high temperature differential normally obtained through the use of high temperatures on the black characters. In our process, the temperature diierential between the black characters and the transfer composition is preferably at least 2 F. The temperature on the black letter characters is preferably between 125 F. and 140 F.

In the preferred procedures, the original, the transfer sheet, and the copy sheet are brought into intimate contact pressure relationship with each other by the use of a vacuum frame preferably at a pressure of approximately l2 pounds per square inch at a temperature on the black letter outlines below approximately F. and a maximum temperature on the transfer composition above the ow point of the transfer composition and below the melting point of said transfer composition.

if it is desired to make a second generation master, or if the original paper is too poor or too weak to be employed as a master, a thin translucent, high wet-strength paper 11 is placed between the heat sensitive transfer sheet 3 and the original copy 1. All three sheets are clamped together to give good contact and exposed to an infra red light source. After cooling and separation, the intermediate sandwiched sheet 11 is the master. Similarly, copies may be made either by the shoot-through process or by the reflex method of irradiation with infra red. In the reliex method the infra red radiations do not go through the original but heat image is generated at the imaged areas which traverses back through the copy sheet Y to the heat sensitive transfer sheet, thus producing copy on the copy sheet.

As another Variant to the process, a master can be made which is satisfactory for use in the hectograph, gelatin process simply by taking the original and placing it face down so that the characters or designs are in contact with the coating of the hectograph transfer sheet. Upon exposing the sheet to infra red radiation, cooling, and separating, the original sheet will contain the hectograph composition on the original characters or design and the sheet can be used as a master, which, in turn, can be used with a hectograph gelatin mass to produce satisfactory copy.

Another variation of the process produces a master for use on offset and direct lithographie processes. The process is carried out by placing a lithographic transfer sheet with its lithographie wax surface in contact with the hydrophylic surface of the direct image mat. The

lithographie transfer sheet consists of a thin, transparentV base sheet coated with a lithographie oleaginous composition. On top of, and in contact with the transparent base sheet, is placed an original copy, such as a typewritten sheet having a printed letterhead. For preparing a master for an offset lithographie process, the copy sheet is placed so that the characters or designs are face up from the infra-red source and for preparing a master suitable for use with a direct lithographie process, the characters are placed face down against the top of the transparent sheet. The sheets are placed in intimate contact, such as by' means of clamping or other pressure applying means, such. as for example a vacuum frame. The copy sheet is exposed to an infra red radiation source after which theV assembly is allowed to cool and the direct image mat is: separated from the transfer and copy sheet. It will be'V found that now the imaged material has been placed on the mat in register delineating the copy of the original, the mat or master can now be applied to a suitable lithographic duplicator and handled in known fashion to produce multiple copies.

Facsimile copies may be produced by placing a sandwich of the original, a transfer sheet and a copy sheet in contact so that the waxy surface of the transfer sheet is in direct contact with the copy sheet. Upon irradiation with infra red radiation, transfer from the transfer sheet to the copy sheet is made in those areas of the original copy to produce transfer to the copy sheet upon separation of the sandwich.

Stencils suitable for use in the mimeograph process may also be made by this thermographic process. In this instance, the original is placed in intimate Contact with the stencil and upon irradiation by infra red the stencil will flow and transfer in those areas reproducingy the black imaged characters on the original to produce a stencil sheet suitable for use in mimeograph.

lt has been found that the process is most satisfactorily carried out by use of a vacuum frame which holds the various sheets in intimate contact with each other and eliminates air from the interleaving of the sheets. Preferably, the process is carried out at a pressure of between 2 and 15 pounds per square inch, with 12 pounds per square inch being the optimum.

To produce copy by what is known as the Shoot-thru process, an original which has been imaged by typing, writing, drawing, Xerography, photography, the Verifax process, etc., on a sheet of paper, is placed face down, i.e., the imaged side towards an infra red light emission source. On top of this, the transfer sheet is laid face up (i.e., with e coated side away from the light emission source). On top of this combination is applied a sheet of paper or other suitable material such as a hydrolized acetate sheet, a piece of cloth, or other material. Pressure is then applied to keep all three components in intimate contact and infra red energy is applied preferably by allowing a line source of 'mfra red energy to traverse across the face of the original. Pressure is then released and the three components separated, and it will be found that the topmost sheet, or copy sheet, now bears a direct facsimile copy of the original.

To produce copy by what is known as Reflex No. l Procedure, which may be desirable if the original contains copy on both sides or if the original is on such stock that it is unsuitable for the transmission of infra red energy, or will diffuse infra red energy, or will not transmit infra red energy, the Reex process described below is employed.

The coated transfer is laid down first, with the wax side up. It is assumed that infra red energy is entering from below so that term down refers to the infra red light emitting source. Next, a sheet of suitable copy paper, cloth, or other ink receptive material is applied. As a topmost layer, the original suitably imaged, as described above, is applied with the copy side down, i.e., towards the light source. Then pressure is applied to maintain all three components in close and intimate contact and infra red energy is applied by traversing the light source, by traversing the assembly, or by combinations of such methods. On release of pressure and separation of the components, it will be found that now a Reflex copy of the original has been obtained which is a direct facsimile of the original.

As an alternate method of reflexing, the following procedure can be used. It is desirable, in this case, that the copy paper be a translucent or transparent sheet. The translucent or transparent sheet is laid down first, i.e., closest to the light source. The transfer sheet is then placed down with the waxed side face down, i.e. towards the infra red light source. On top is placed the original with the imaged side down. Pressure and traversing with infra red radiation is carried out as described above and on release of pressure and separation of the components, it will now be found that a facsimile copy has been obtained. Such copy must, of course, be read through the transparent copy paper, since the printing is on the reverse side and is in reverse. Such copy, however, is perfectly acceptable and readable for commercial usage.

Alternatively, a combination of Reflex 1 and 2 methods may be employed -to copy an original. Thus, a transfer sheet coated with a wax composition is laid face up closest to the light source. On this is laid a sheet of copy paper, then another sheet of transfer coating face down. Then, the original is laid face down and pressure applied. Infra red energy is applied as described above. The copy now is imaged on front and back in register in direct facsimile of the original.

In the imaging of direct image mats, we have also developed a process which has technical advantages, includi-ng the elimination of background. This procedure involves assembling an original, copy side down, and placing -a lithograph transfer sheet on top of this with the transfer side down. Pressure and vacuum, as well las infra red radiation, are then applied, as Vtaught heretofore, to produce transfer of the lithograph material to the back of the original. The copy thus produced is then assembled, lithograph transfer maten'al side against the working face of a direct image mat, and the assembly is then placed in the infra red radiation device with the original copy side down. Vacuum and pressure are applied again, resulting in a retransfer of the waxy material to the face of the direct image mat. This can be repeated several times to image several mats from one transfer of lithograph material to the back of an original.

The transfer compositions vary with the type of master to be produced or the type of copy to be made. For spirit process and hectograph masters, the thermoplastic composition can suitably comprise a wax containing an alcohol and water soluble dye, such as the methyl and crystal violet dyes; for chemical reaction type duplication the composition can comprise a wax and a chemical agent which will react with another reagent to produce black or other colors; for planograph or lithograph duplication the composition can consist of an oleaginous material, such as a paraffin wax with or without dye or pigment or other lithograph type inks. For fascimile copying, the composition can be a wax containing a dye or pigment.

The Wax compositions that we have found to be most desirable are narrow cut distilled fractions which have a carbon length of 29 to 31 carbon atoms and the percentage of straight chain carbons is 84 to 99 percent. WaXes of this type are sold under the trade names Sun Oil 5512 and 4412 and Socony Mobile types.

Following are examples of suitable transfer compositions:

HECTO CARBON FORMULATION The type of paper used in the process is important.

'For example, it is important that the paper used for producing the transfer material have certain specific and narrow physical characteristics to obtain performance at a minimum infra red radiation level and for maximum commercial quality in the duplicated material. Thus, for example, the carbonizing tissue used to produce the transfer material for copying, for imaging of direct image mats, should have the following characteristics:

mils

Caliper 0.9-2.8 Smoothness (Sheffield) 17-260 Densichron range OOO-0.30 Infra red homogeneity of sheet 0.00-0.05

The carbonizing tissue used to produce hecto carbonizing transfer material should preferably have the following characteristics:

Caliper mils 1.1-3.7 Smoothness (Sheffield) 17-120 Oil bleed minutes 2-40 Densichron range 0.01-0.10 Infra red homogeneity Q2-0.06

The paper used for preparing an original for preparation of a first generation hectograph master; for preparation of a second generation hectograph master; for single copy shoot-thru or for imaging a direct image mat by a shootthru process, should preferably have the following characteristics:

Caliper mils" 1.1-2.6 Smoothness (Sheiield) 3.0-32() Infra red Densichron range 0.00-0.10 Infra red homogeneity per sheet 0.00-0.10 Ash content Percent-- 0.8- Opacity (Bausch & Lomb Opacimeter), maximum 80 The intermediate sheet which is converted to a master for second generation hecto master preparation preferably should have the following characteristics:

Caliper mils 1.0-2.6 Smoothness (Sheield) 21-250 Infra red Densichron range 0.00-0.06 Infra red homogeneity 0.00-0.04 Ash content percent 0.8-10

The sheet which is between the original image sheet and the infra red source which is converted to a copy by the reex variation of the copying process should preferably have the following characteristics.

Caliper mils 1.0-2.6 smoothness (Sheffield) 30-320 Infra red Densichron range 0.00-0.10 Infra red homogeneity 0.00-0.04 Opacity, maximum 80 EXAMPLE I Preparation of Spirit Process Masters A transfer sheet consisting of a paper sheet coated with a composition having the following formula was used in this example:

Parts by Weight Wax (carnauba) 13 Oil 33 Crystal violet 54 A sheet of paper 1 having the printed characters 2 on the front was placed in contact with a hectograph carbon sheet 3 having a coating 4 and base 5, so that the Characters are face up and the back of the sheet 1 is in contact with the coating 4. This sheet assembly was clamped on a drum 6 by means of clamp 7, so that the carbon 3 and the paper 1 were in close Contact, free of wrinkles, packers, or bulges. Beneath the roller was a member 8 having an adjustable slit 9. The infra red radiation source 10 was now turned on and the drum 6 was allowed to rotate past the slit 9, resulting in a complete exposure of the paper 1 to the infra red radiation. An infra red radiation source of 1350 Watts at a distance of l/l inch from the sheets Was used at an exposure time of $50 second for each line of printed characters.

The carbon paper 3 and the original paper 1 Were then allowed to cool, released from the drum 6 and drawn over an edge as, for example, the edge of a desk, to separate the two. It was noticed on examination that the original paper 1 then had transfer material 2a on the back of the original sheet in exact register and delineating satisfactorily the copy which was on the face of the original. In other words, the original copy had been successfully converted to a master which could be placed on a spirit duplicating machine. In these machines, copy paper is passed through the duplicating machine, moistened slightly with a suitable uid, such as ethyl alcohol, and the master brought into fleeting contact with the copy paper with a resultant production of copy.

EXAMPLE II Second Generation Muster The hectograph carbon paper was positioned face up on the drum, as described in Example l, and then a translucent high wet strength paper 11 was then placed against the coated face of the carbon, and the imaged original paper 1 Was placed on this, as shown in the arrangement of FIG. 4. All three were clamped, drawn taut free of Wrinkles and bulges, and processed as described in Example I. Upon separation, images 12 were formed on the back of the copy sheet 11. An infra red radiation source of 1350 watts, at a distance of 1A@ inch from the sheets was used at an exposure time of 1/10 second.

EXAMPLE III Process of Producing a Master for Use with a H ectograph Process ess, it was found that a master was now produced reading from left to right as regards the transfer material Which in turn could be used with a gelatin hectograph mass to produce satisfactory copy.

EXAMPLE IV Preparation of a Master for Use in a Chemical Reaction Type Duplicating Process The process was carried out the same as in Example I except that a transfer sheet was used in which the `coating had the following composition:

EXAMPLE V Method f Producing Masters for Oset Planograph Duplicating Process The process was carried out by placing the original face down on the support, placing a transfer sheet having a lithographie wax surface face up, and then placing a lithographie mat with the hydrophylie surface of the mat in contact with the waxy Itransfer surface of the transfer sheet, clamping them together as in Example I and irradia-ting to produce a transfer `of the lithographie transfer material onto lthe hydrophylic surface of the lithographie mat to produce a direct reading copy. It was found that the imaged material had been placed in register and delineated the `characters of the original. The direct image mat or master could now be applied to an offset duplicator to produce multiple copies.

EXAMPLE VI Method of Producing Masters for Direct Lithographie Process The process was carried out by placing the original imaged side up, lthen a sheet of trwsfer material waxed side up, then a direct image imat hydrophylic side down, to obtain imaged material reading in mirror image on the direct image mat. This gave a master suitable for use with the direct lithographie process.

EXAMPLE VII Method of li/Iaking a Facsimile Lithographie Negative The process involves the use of a sheet of paper, plastic, or other suitable material, which has been covered with a masking medium which may consist of a wax, resin, or similar type of material containing preferably a pigment or dye or combinations thereof which is opaque to ultra-violet radiation. This top coat is sensitive to heat so that it becomes liquid or tacky when exposed to heat. The process is carried out by taking a typewritten, drawn, or otherwise prepared copy on a piece of copy paper which has the desired contrast as described heretofore. To prepare an odset lithographie plate this copy paper is placed on top of the described sheet with the copy side facing the infra red radiation. Heat is then applied while maintaining pressure as described heretofore, the sandwiched layer being allowed to cool and `then separated. It will be noticed that as a result of this procedure a stencil or a lithograpmc negative has been prepared which deiineates exactly the original on this sheet. This stencil can now be placed on top of a presensitized lithographie mat, exposed to ultra-violet radiation or other satisfactory light source and the lithographie plate processed in accordance with a well known manner to produce satisfactory copies.

If it is desired to prepare a presensitized lithographie plate for use on a direct lithographie machine, the sheet of transfer material is laid coated side up and the original copy is laid imaged side up in close contact. The process is now carried out as above, and it will -be found that a lithographie negative is now obtained read-ing from right to left, suitable for the direct lithographie process. Additionally, it should be pointed out that this method of preparing a stencil may be satisfactory for use with the mimeograph type of duplicator following the above examples.

EXAMPLE VIH Method of Producing a Facsimile Copy In preparing facsimile copies the original is placed 10 face down, a transfer sheet containing wax and suitable pigments or dyes is placed in lcontact wax side up and a copy sheet is placed on top against the waxy composition. Upon radiating as in the above examples, a facsimile copy is produced which has .the higly desirable characteristics of being dry and heat and light resistant.

In these examples, suitable copies may be produced by the reflex method of copying where the original is on top of the sandwich and infra red energy does not pass through i-t, but rather a heat image is transmitted back from the original. The advantage of this method of producing copy is that using known copy paper and transfer sheets, `satisfactory copy can be obtained in each instance without reference to the absorbency or reflectivity of the origind such 'as is necessary when the inf-ra red radiations are rnade to pass through the original before reaching the transfer sheet and copy sheet.

in the kabove examples the transfer or carbon compositions comprise a solid oleaginous material such as parafn wax, amorphous wax, carnauba wax, bees wax, or any of the waxes used in hectograph, spirit process, or chemical reaction type carbon papers, used alone or in mixture with oils and greases, so that the composition has a characteristic of being tacky or liquid and transferable at a temperature above normal room temperature, for example, F., and solid and non-tacky at normal room temperature.

The temperature on the copy characters produced by the infra a'ed lamp -was approximately 135 F. and was below the melting temperature of the transfer composition `on the noneimaged portions. r)The transfer composition twas a wax contm'ning solid at normal 4room temperature, and a mixture of solid and molten wax at or slightly above the temperature on the characters or like imaged portion of the original. The specific carnauba waxnuneral oil composition used had a flow point of 79 F. at a p.s.i. of 12 pounds, and a melting point of 158 F. However, a suitable range is 75 F.81 F. for ilow point and 151 F. to 172 F. -for melting point. The specic parain wax had a ilow point of F. at a pressure of 12 pounds per square inch, and a melting point of 150 F. The microcrystaline wax had a flow point at this pressure of 104 F. and a melting point of 149 F.

Wax compositions having a flow point of 100 F. to F. and a melting point at least 2 F. above the dow point are prefenred.

Suitable transfer compositions are given in the above examples, but it should be understood that the process is not restricted to these specific compositions. Waxes in general have the property of adhering to paper when hot so that a composition containing a substantial portion of any wax is suitable, it being well known how to incorporate the wax, such as a high melting wax, with other lower melting waxes, greases or oils to bring the softening point of the transfer composition within the temperature readily obtainable with an infra red radiation source as herein defined. In the preferred process of the invention, the image on the copy sheet, such as the characters or designs are heated quickly before much heat can be conducted to the surrounding non-imaged portions of the copy and to the meltable transfer composition immediately in Contact with it. This result is accomplished by exposing the surface of the copy paper to the infra red radiation from a reflecting device as shown in FIG. 1 and then moving said rellecting device, having an infra red bulb therein, past from one end of the sandwich to the other. The assembly of copy paper, transfer sheet and, when used, intermediate sheet are preferably in pressure contact with each other, said pressure contact being brought about by means of a vacuum frame.

It has been lfound that it is highly advantageous to employ the greatest possible contrast as far as color in- .tensity between unprinted areas and the printed areas and inks which are known to be relatively high in absorbency for infra red are preferred for the preparation of originals. Likewise, it has been found that the paper on which the original should be prepared is preferably as homogeneous as possible, free of intermediate barrier layers or infra red light absorptive fillers insofar as possible or free from top and/ or bottom coatings of such materials.

It has been found that there is some advantage for certain types of original copy to use a transparentizing uid to produce a better master but normally this is not necessary.

The above processes are based on the differential absorp'tion of heat by characters or designs and the reflection of infra red light from un-imaged surfaces.

Another method which would give satisfactory results for some purposes is carried out by using a stencil such as a cut stencil in place of the original. An intermediate sheet to receive the image is placed between the transfer layer and the stencil sheet. Preferably this side of the intermediate sheet next to the infra red source is more heat absorptive than the surface of the stencil. For example, stencil sheet next to the infra red is white and the side of the intermediate sheet next to the infra red is black. Also, the'stencil sheet should be paper or some other material that does not readily conduct heat. The method of carrying out this stencil process is as follows: A suitable cut stencil is placed imaged side down, on top of this a sheet of black or other absorptive material, and on top of this-a sheet of suitable transfer carbon waxed side down. The sheets should be so clamped that the layers are in close contact, free of wrinkles, puckers or bulges. The infra red radiation source is now turned on and is allowed to pass across the length of the sandwich for a complete exposure of the stencil to the infra red radiation. Carbon and master are now allowed to cool, released from the support and separated. It will be noticed on examinaf tion that the master paper now has transfer material on the back in exact register and delineating satisfactorily the stencil. In other words, the copy on the original stencil has now been successfully transferred to a master which may be placed on a spirit duplicating machine or variance of such a machine, device, or operation, with chemical reaction and related processes and copy may be prepared in the conventional manner. In other words, copy paper may be passed through the duplicating machine, moistened slightly with a suitable uid depending upon the process being employed, and the master brought in eeting contact with the copy paper with the resultant production of copy.

As another variant of this process, it is possible to produce a master which is satisfactory for use with the gelatin process simply by taking the stencil and placing it face up on the support. A sheet of suitable transfer material, waxy side up, is placed on top, followed by a suitable master paper. On carrying out the process described above, it will be found that a master is now produced reading right to left as regards the transfer material, which in turn can be used with a gelatin mass which will produce satisfactory copy.

It has been found that the master paper is preferably as homogeneous as possible, free of intermediate barrier layers and free of heavy light-reflective or light-absorptive fillers insofar as possible, or free from top and bottom coatings of such materials. In addition, the back of the master paper or the entire master paper may be tinted or colored with suitable relatively high infra red absorptive material.

As regards the type of transfer material that has been employed, it has been found that the carbon known as hectograph carbon is very satisfactory in this process although any of the carbon papers heretofore mentioned may be used, depending upon the type of master desired. The carbon papers disclosed produce a owable composition having a narrow range between ow point and melting point, a relatively sharp transfer point and reharden relatively rapidly after exposure to the infra red radiation. 'I'hey adhere to the master paper under the conditions of operation of this process. The carbons give sharp, complete release. It should again be noted that transfer materials can be used which have a relatively high infra red absorbency, such as crystal and methyl violet dyes, and that in order to carry out the process the temperatures at the character level should be below F. but slightly above the ow temperature of the transfer composition, with the temperature differential between the two being relatively low, as mentioned above.

As still another variant of this process, it is possible to produce a master from a stencil, said master being suitable for use in the planographic printing process. In carrying out this process, the stencil image sheet is placed in contact with the back side of a lithographie carbon, the transfere surface of which carbon is in turn placed in contact with a direct image mat, and exposing the image mat through the stencil image to infra red radiation. If the stencil is placed on a lithographic carbon reading from left to right, an offset direct image mat results for use in connection with the olfset planographic process. If the stencil image sheet is reversed, that is, reading from right to left, there will be produced a direct image mat reproducing the stencil image but in mirror image which is suitable for use in connection with direct lithographie processes.

When waxed or overcoated spirit carbon sheets are employed, the waxed or overcoat layer is laid on as smoothly and evenly as possible with proper adherence of the ink to prevent separation at this interface and the wax or overcoat layer has a sharp, relatively low melting point and Va rapid setting after exposure to the infra red radiation in order to give maximum performance. Furthermore, it is advantageous to have this wax layer laid down in as thin a layer as possible, as for example, by means of a bar knife.

It has been found that the cut stencil employed as an original to image direct image lithographic mats or make hectograph masters should preferably be of a nature to reect infra red radiation or to prevent passage of infra red radiation without development and transmission of heat wherever the stencil has been cut or incised. Thus, an aluminum powder containing stencil is advantageous.

This application is a continuation of the applicants previously copending application, Serial No. 726,378, filed on April 4, 1958, now abandoned, which last-named application is a continuation-in-part of the presently pending application, Serial No. 548,056, filed November 21, 1955.

Having described our invention and certain of its preferred embodiments and having given examples illustrating the use and eectiveness of the same, we claim as our invention all that is commensurate with the spirit and scope of the following claims:

1. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including,

(l) an original sheet having image portions which are infrared absorbing-heat generating and nonimage portions which are substantially noninfrared absorbing-heat generating,

(2) a copy sheet, and

(3) a transfer sheet made up of a base sheet carrying on one surface thereof a layer of transfer material which is solid at room temperature and softenable at temperatures above normal room temperature; and

(B) which comprises the steps of,

(1) forming an assemblage of sheets wherein,

(a) the copy sheet is in surface contact with the original sheet, and

(b) the layer of transfer material is in surface Contact with said copy sheet; and

(2) directing a suflcient quantity of radiations rich in infrared directly onto said original sheet 13 prior to said radiations striking the other sheets in the assemblage to generate substantially instantaneously a temperature rise in the image portions of the original sheet thereby to reduce the materialV in the corresponding arcas of the transfer material to a softened condition, so that said softened material in said areas transfers to said copy sheet to produce an image; the improvement wherein the original sheet and the copy sheet through which infrared radiations pass have the following characteristics:

Original sheet:

2. The method as set forth in claim l being further characterized in that said layer of transfer material is suitable for the production of spirit process duplicating masters.

3. The method of claim 2 being further characterized in that said layer of transfer material contains from approximately forty to sixty percent of a dye selected from a group consisting of crystal violet wd methyl violet dyes.

4. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including,

( 2) a copy sheet, and

(3) a transfer sheet made up of a base sheet carryon one surface thereof a layer of transfer material which is solid at room temperature and softenable at temperatures above normal room temperature; and

(B) which comprises the steps of,

(l) forming an assemblage of sheets wherein the copy sheet is in surface contact with the original sheet, and

(2) directing a sufhcient quantity of radiations rich in infrared onto the original sheet prior to said radiations striking said other sheets to generate substantially instantaneously a temperature rise on the image portions of the original sheet to reduce the material in the corresponding areas of the transfer material to a softened condition so that said softened material in said areas transfers to said copy sheet to produce an image;

the improvement wherein the original sheet through which infrared radiations pass has the following characteristics:

5. The process of claim 4 being further characterized in that said layer vof transfer material is suitable for the production of spirit process duplicating masters.

6. The process of claim 4 being further characterized in that said layer of transfer material contains from approximately forty to sixty percent of a dye selected from the group consisting of crystal violet and methyl violet dyes.

7. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including,

(2) a copy sheet, and

(B) which comprises the steps of,

(l) forming an assembly of sheets wherein,

(rz) the layer of transfer material is in surface contact with said copy sheet, and

(b) the original sheet is in surface contact with the base sheet of said transfer sheet; and

(2) directing the sufficient quantity of radiations rich in infrared directly onto said original sheet prior to said radiations striking the other sheets the assemblage to generate substantially instantaneously a temperature rise in the image portions of the original sheet, thereby to reduce the material in the corresponding areas of the transfer material to a softened condition, so that said softened material in said areas transfers to said copy sheet to produce an image;

the improvement wherein the original sheet and the base sheet of the transfer sheet have the following characteristics:

Original sheet:

Caliper mils 1.1-2.6 Smoothness (Sheffield) 3.0-320 Infrared Densichron range 0.00-0.l0 Infrared homogeneity 0.00-0.10 Ash content percent 0.8-10 Opacity (Bausch & Lomb Opacirneter),

maximum Base sheet of the transfer sheet:

Caliper mils 0.9-2.9 Smoothness (Sheffield) 17-260 Densichron range ODO-0.30 Infrared homogeneity 0.00-0.05

8. The process as set forth in claim 7 being further characterized in that said transfer material is an olephilic lithographie composition and the copy sheet is a lithographic mat having a hydrophillic surface in contact with the surface of the transfer sheet.

9. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including,

(l) an original sheet having image portions which are infrared absorbing-heat generating and nonirnage portions which are substantially noninfrared absorbing-heat generating,

(2) a copy sheet, and

(B) which comprises the steps of,

(1) forming an assemblage of sheets wherein,

(a) the copy sheet is in surface contact with the original sheet, and

(b) the layer of transfer material is in surface Contact with said copy sheets; and; (2) directing a suiiicient quantity of radiations rich in infrared onto the said transfer sheet and then through the copy sheet onto the original sheet to generate substantially instantaneously a temperature rise on the image portions of the original sheet to reduce the material on the corresponding areas of the transfer material to a softened condition, so that the softened material in said areas transfers to said copy sheet to produce an image; the improvement wherein the copy sheet and the base sheet of the transfer sheet through which infrared radia- 10. The method as set forth in claim 9 wherein said copy sheet is in surface contact with the imaged side of the original sheet and the transfer material is suitable for the production of gelatin duplicating masters.

11. The method as set forth in claim 9 wherein said copy sheet is in surface contact with the imaged side of said original sheet, and the transfer material is an oleophillic lithographie composition and the copy sheet is a lithographie mat having a hydrophillic surface in contact with the surface of the transfer sheet.

12. The method of claim 9 wherein the copy sheet is in surface contact with the imaged side of the original sheet.

13. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including,

(2) a copy sheet, and

(3) a first transfer sheet and a second transfer sheet, each made up of a base sheet carrying on one surface thereof a layer of transferable material which is solid at normal room temperatures and reducible to a softened condition at above normal room temperature; and

(B) which comprises the steps of (1) forming an assemblage of sheets wherein,

(a) said copy sheet is disposed between said first and second transfer sheets and in surface contact with the layers of transfer material thereof, and

(b) the original sheet is in surface contact with said first transfer sheet; and

(2) directing a suicient quantity of radiations rich in infrared onto the second transfer sheet and then through the copy sheet and said first transfer sheet onto the original sheet to generate substantially instantaneously a temperature rise on the image portions of said original sheet to reduce the material in the corresponding areas of the layer of transfer material to a softened condition, so that said softened material in said areas transfers to said copy sheet to produce images thereon;

the improvement wherein the base sheet of said first and second transfer sheets and the copy sheet through the infrared radiations pass have the following characteristics:

Base sheet:

Caliper -..mils 0.9-2.8 smoothness (She'ield) 17-260 Densichron range 0.00-0.30Y Infrared homogeneity ODO-0.05 Copy sheet:

Caliper mils 1.0-2.6 Smoothness (Sheffield) 30-320 Infrared Densichron range 0.00-0.10 Infrared homogeneity 0.00-0.04 Opacity (Bausch & Lomb Opacimeter),

maximum 14. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including, (1) an original sheet having image portions which are infrared absorbing-heat generating and non-image portions which are substantially noninfrared absorbing-heat generating, 2) a copy sheet, and (3) a transfer sheet made up of a base sheet carrying on one surface thereof a layer of transfer material which is solid at room temperature and softenable at temperatures above normal room temperature; and (B) which comprises the steps of,

(l) forming an assemblage of sheets wherein,

(a) the copy sheet is in surface contact with the original sheet, and (b) the layer of transfer material is in surface contact with said copy sheets; and (2) directing a sufficient quantity of radiations rich in infrared onto the copy sheet and then through the transfer sheet onto the original sheet to generate substantially instantaneously a temperature rise on the image portions of the original sheet to reduce them materially in the corresponding areas of the transfer material to a softened condition, so that the softened material in said areas transfers to said copy sheet to produce an image; the improvement wherein the copy sheet and the base sheet of the transfer sheet through which infrared radiations pass have the following characteristics:

Copy sheet:

maximum 80Y Base sheet:

Caliper mils O.9-2.8 Smoothness (Sheffield) 17-260 Densichron range ODO-0.30 Infrared homogeneity 0.00-0.05

15. The method of claim 14 wherein the base sheet of said transfer sheet is in contact with the imaged side of said original sheet and the transfer material is suitable for the production of spirit process duplicating masters.

16. The method as set forth in claim 15 wherein said transfer material contains some forty to sixty percent of the dye selected from the group consisting of crystal and methyl violet dyes.

17. The method as set forth in claim 14 wherein the transfer material is an oleophilic lithographie composition and the copy sheet is a lithographic mat having a hydrophilic surface in contact with the surface of said transfer sheet.

18. In a method of making reproductions from an original sheet 1 7 (A) which employs an assemblage of -sheets including,

(1) an original Vsheet having Vimage portions which are infrared absorbing-heat generating and nonimage "p'o'r'tio'ns which are substantially noninfrard'ab'srBrng-neat generating,

(2) a copyslieetfand Y (3) a transfer slie'et made up of a base sheet carrying on one 'surface thereof a layer of transfer mate'rial -which is solid at room temperature and softenable at temperatures 'above normal room temperature; and

(B) which comprises the steps of,

(1) forming an assemblage of sheets wherein the copy sheet is in surface contact with the original sheet, and

(2) directing a sufficient quantity of radiations rich in infrared onto the original sheet prior to said radiations striking said other sheets to generate substantially instantaneously a temperature rise on the image portions of the original sheet to reduce the material in the corresponding areas of the transfer material to a softened condition so that said softened material in said areas transfers to said copy sheet to produce an image;

19. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including, (l) an original sheet having image portions which are infrared absorbing-heat generating and nonimage portions which are substantially non-infrared absorbing-heat generating, (2) a copy sheet, and (3) a transfer sheet made up of a base sheet carrying on one surface thereof a layer of transfer material which is solid at room temperature and softenable at temperatures above normal room temperature; and (B) which comprises the steps of,

(l) forming an assemblage of sheets wherein,

(a) the copy sheet is in surface contact with the original sheet, and (b) the layer of transfer material is in surface contact with said copy sheet; and (2) directing a sufficient quantity of radiations rich in infrared directly onto said original sheet prior to said radiations striking the other sheets in the assemblage to generate substantially instantaneously a temperature rise in the image portions of the original sheet thereby to reduce the material in the corresponding areas of the transfer material to a softened condition, so that said softened material in said areas transfers to said copy sheet to produce an image; the improvement wherein the original sheet and the copy sheet through which infrared radiations pass have the following characteristics:

V20. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including, (1) han original sheethaving portions which are infrared absorbing-heat generating and nonimage portions which are substantially noninfrared absorbing-heat generating, (2) a copy sheet, and (3) a transfer sheet made up of a base sheet carrying on one surface thereof a layer of transfer materialwhich is solid at room temperature and softenable at temperatures above normal room temperature; and (B) which comprises the steps of,

(l) forming an assemblage of sheets wherein,

(a) the copy sheet is in surface contact with the original sheet, and (b) the layer of transfer material is in surface contact with said copy sheets; and (2) directing a suflicient quantity of radiations rich in infrared onto the said transfer sheet and then through the copy sheet onto the original sheet to generate substantially instantaneously a temperature rise on the image portions of the original sheet to reduce the material on the corresponding areas of the transfer material to a softened condition, so that the softened material in said areas transfers to said copy sheet to produce an image; the improvement wherein the copy sheet and the base sheet of the transfer sheet through which infrared radiations pass have the following characteristics:

Copy sheet:

Caliper mils 1.0-2.6 Smoothness (Sheffield) do 30-320 Infrared Densichron range 0.00-0.l() Infrared homogeneity 0.00-0.04 Base sheet of transfer sheet:

Caliper mils 0.9-2.8 Smoothness (Sheflield) 17-260 Infrared Densichron range 0.00-0.30 Infrared homogeneity 0.00-0.05

2l. In a method of making reproductions from an original sheet (A) which employs an assemblage of sheets including, (l) an original sheet having image portions which are infrared absorbing-heat generating and nonimage portions which are substantially noninfrared absorbing-heat generating. (2) a copy sheet, and (3) a transfer sheet made up of a base sheet carrying on one surface thereof a layer of transfer material which is solid at room temperature and softenable at temperatures above normal room temperature; and (B) which comprises the steps of,

(1) forming an assembly of sheets wherein,

(a) the layer of transfer material is in surface contact with said copy sheet, and (b) the original sheet is in surface contact with the base sheet of said transfer sheet; and (2) directing the suliicient quantity of radiations rich in infrared directly onto said original sheet prior to said radiations striking the other sheets in the assemblage to generate substantially instantaneously a temperature rise in the image portions of the original sheet, thereby to reduce the material in the corresponding areas of the transfer material to a softened condition, so that said softened material in said areas transfers to said copy sheet to produce an image; the improvement wherein the original sheet and the base sheet of the transfer sheet have the following character- References Cited in the le of this patent 15h08: I UNITED STATES PATENTS Ons'lnnlheen 1,925,235 Dixon sept. 5, 1933 Cannf -nn1S 1-1-2-6 ,5 2,016,599 Graves oct. s, 1935 Infrared DnnSIChIOn range 00t0-10 2,501,495 Carroll et al Mar. 21,1950 Infrared homogeneity 000010 2,740,895 Miller Apr, 3, 1956 Ash Content Percent-H 0-8-10 2,800,077 Marron July 23, 1957 BnSeShnfOf transfefsheefr I 2,808,777 Roshkind oct. s, 1957 CnhPef --nn1S- 094-9 lo 2,939,009 Tien May 31, 1960 smoothness (Shefeld) 17-260 Densichron range 0.00-0.30 FOREIGN PATENTS infrared homogeneity 0.00-0.05 722,023 Great Britain Ian. 19, 1955 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No., 3,122,997 March 3, 1964 Walter A. Raezynski et alu It is hereby certified that error appears in the above numbered patent req'irng correction and that the Said Letters Patent should read as corrected below.

Column I3, line 44, for "carrya" read Carrying column I4, line 28, after "sheets" insert in line ,'55q

lines 23 and 24, insert the title Base sheet of transfer sheet: saine column I5, Ine 25Y for i"7l-260" read 17g-260 column I7Y line 29Sl for "'Densscron" read Densichron Column I8Y line 4, after "hai/ing" insert image nu,

Signed and sealed this 21st day of July l94 (SEAL) Attest:

TESTN Go JHNSON EDWARD J BRENNER g @CSI Commissioner of Patents

Claims

7. IN A METHOD OF MAKING REPRODUCTIONS FROM AN ORIGNAL SHEET (A) WHICH EMPLOYS AN ASSEMBLAGE OF SHEETS INCLUDING, (1) AN ORIGINAL SHEET HAVING IMAGE PORTIONS WHICH ARE INFRARED ABSORBING-HEAT GENERATING AND NONIMAGE PORTIONS WHICH ARE SUBSTANTIALLY NONINFRARED ABSORBING-HEAT GENERATING, (2) A COPY SHEET, AND (3) A TRANSFER SHEET MADE UP OF A BASE SHEET CARRYING ON ONE SURFACE THEREOF A LAYER OF TRANSFER MATERIAL WHICH IS SOLID AT ROOM TEMPERATURE AND SOFTENABLE AT TEMPERATURES ABOVE NORMAL ROOM TEMPERATURE; AND (B) WHICH COMPRISES THE STEPS OF, (1) FORMING AN ASSEMBLY OF SHEETS WHEREIN, (A) THE LAYER OF TRANSFER MATERIAL IS IN SURFACE CONTACT WITH SAID COPY SHEET, AND (B) THE ORIGINAL SHEET IS IN SURFACE CONTACT WITH THE BASE SHEET OF SAID TRANSFER SHEET; AND (2) DIRECTING THE SUFFICIENT QUANTITY OF RADIATIONS RICH IN INFRARED DIRECTLY ONTO SAID ORIGINAL SHEET PRIOR TO SAID RADIATIONS STRIKING THE OTHER SHEETS THE ASSEMBLAGE TO GENERATE SUBSTANTIALLY INSTANTANEOUSLY A TEMPERATURE RISE IN THE IMAGE PORTIONS OF THE ORIGINAL SHEET, THEREBY TO REDUCE THE MATERIAL IN THE CORRESPONDING AREAS OF THE TRANSFER MATERIAL TO A SOFTENED CONDITION, SO THAT SAID SOFTENED MATERIAL IN SAID AREAS TRANSFERS TO SAID COPY SHEET TO PRODUCE AN IMAGE; THE IMPROVEMENT WHEREIN THE ORIGINAL SHEET AND THE BASE SHEET OF THE TRANSFER SHEET HAVE THE FOLLOWING CHARACTERISTICS: ORIGINAL SHEET: CALIPER MILS 1.1-2.6 SMOOTHNESS (SHEFFIELD 3.0-320 INFRARED DENSICHRON RANGE 0.00-0.10 INFRARED HOMOGENEITY 0.00-0.10 ASH CONTENT PERCENT 0.8-10 OPACITY (BAUSCH & LOMB OPACIMETER), MAXIMUM 80 BASE SHEET OF THE TRANSFER SHEET: CALIPER MILS 0.9-2.9 SMOOTHNESS (SHEFFIELD) 17-260 DENSICHRON RANGE 0.00-0.30 INFRARED HOMOGENEITY 0.00-0.05
8. THE PROCESS AS SET FORTH IN CLAIM 7 BEING FURTHER CHARACTERIZED IN THAT SAID TRANSFER MATERIAL IS AN OLEPHILIC LITHOGRAPHIC COMPOSITION AND THE COPY SHEET IS A LITHOGRAPHIC MAT HAVING A HYDROPHILLIC SURFACE IN CONTACT WITH THE SURFACE OF THE TRANSFER SHEET.