US2299014A - Transfer duplicating sheet - Google Patents

Description

Get. 13, 1942. w. D. FOSTER 2,299,014

TRANSFER DUPLICATING SHEET Filed Dec. 1, 1939 lNVENTOR ATTORNEY Patented Oct. 13, 1942 2,299,014 TRANSFER DUPLICATING "SHEET William D. Foster, Mineola, N. Y., assignor to Manifold Supplies Company, Brooklyn, N. Y., a corporation of New York Application December 1, 1939, Serial No. 307,067

7 Claims.

The present invention relates to transfer sheets, and, more particularly, to a hectographic transfersheet of novel and improved character.

As those skilled in the art know, prior to 1900, in the preparation of transfer sheets, such as carbon paper and the like, a lard oil or similar oil base has been used with the addition of tallow to stiffen it and carbon and/or strong dyes and/or other coloring agents had to be added to act as the copying or duplicating agent. This mixture was dissolved in benzine or some other quickly volatilizing' solvent to produce an extremely thin solution to permit application of the ink, such as by brushing by hand and the like, on a sheet of preheated paper. After 1900 all hectographic carbon paper ink, generally speaking, was made by a hot process and consisted essentially of a wax and oil vehicle or base, such as for example carnauba wax, Vaseline, grease and similar materials carrying in suspension at large percentage of strong copying dyestufl or coloring agent. The principal object of the wax content was to cause fluidity of the mass when hot, thus making it possible to apply the ink hot to a Web by a continuous hot coating process and to harden the surface of the product by cooling so as to make it clean to handle and to use. The presence of the wax made the ink in its normal state a hard solid, similar in consistency to sealing wax. In order to liquefy, it was necessary to heat this ink material to a high temperature, approximately 200 Fahrenheit, and in this liquefied condition the ink was applied by hot coating methods to a paper web to manufacture so-called carbon paper. Although various modifications of this basic process have been employed, such as, for example, the use of Vaseline or petroleum jelly and especially recently mineral oil in combination with suitable waxes such as carnauba wax and similar materials, the hot coating process outlined in the foregoing remained fundamentally the same. As a result of this procedure, conventional hectographic papers had a relativelythick coating of a comparatively waxy character. This waxy coating tended to interfere with the natural copyin power of the dyestufl or coloring agent incorporated in the coating vehicle so that much wastage of the color strength of the dye occurred due to the inhibiting wax film which prevented a large portion of the dye from dissolving in the duplicating medium. In addition to this, the conventional hot coating process was also very uneconomic'al in that most of the expensive ink was wasted since neither the area nor the thickness of the coating could be adjusted to the area of the copyable matter and to the number of copies required, respectively. As those skilled in the art know, this was a very important consideration as the cost of dye is about 95% of the cost of the transfer ink and about 70% of such dye usually remains in the transfer sheet unused. Moreover, of the transfer sheets areused for preparing copyable masters for printing less than 50 copies although the dye therein was suflicient for a considerably larger number of copies.

Such conventional transfer sheets have been employed to a very great extent in the art for printing copies, for example carbon copies, and also for preparing the master sheets employed in various duplicating processes, such as the gelatin process and in the so-called spirit duplicating process. In these duplicating processes when it was desired to prepare a master, a sheet of paper coated with an ink having a powerful dyeing or coloring quality was applied to another sheet and the matter to be duplicated was impressed on said sheet by writing or typing. According to the type of duplicating process, the arrangement of the hectographic carbon paper with respect to the master sheet was different. In the gelatin process, the coated side of the hectographic carbon paper was placed against the front face of the master and the impression by typing or writing was made on the front face of the top sheet. In this manner, a positive or legible copy in hectographic ink was provided on the master sheet. This master sheet could be employedin the conventional manner and could be transferred to a colloidal surface, such as gelatin, from which the copies could be taken. In the spirit process, the hectographic carbon paper was placed with its coated surface against the rear face of the master sheet and the impression was made on the front face thereof whereby a negative or mirror-script master was obtained on the rear face or under side of the sheet. This master could be readily applied with pressure against copy sheets previously moistened with a readily volatilizing solvent whereby the matter to be duplicated was transferred to the copy sheets in positive script. As appears from the foregoing, both of these duplicating processes involved the use of coated hectographie transfer sheets. This procedure had various disadvantages. First, all coated hectographic carbon papers have been rather expensive in view of the substantial amount of powerful aniline dye and the like, which had to be provided thereon particularly due to the presence of the inhibiting waxy film. Moreover,-

these conventional hectographic carbon papers of suitable character to a hard wax and oil base,

the finished mixture having a consistency and hardness similar to that of sealing wax. This hard ink was heated to liquefy the same. Thereafter, the fluid was applied to or spread on the paper hot in a continuous manner with practically no pressure and the product was cooled to cause solidification and setting of the coated layer. As a result of this procedure, conventional hectographic carbon papers had a relatively thick coating of ink. In addition to this, the coating process employed in the production of conventional hectographic carbon papers was a continuous operation necessarily covering an area in continuous strips and it wasnot possible to coat only a restricted area thereon in order to provide a clear marginal gripping surface on all four sides of such area, if necessary, or to effect savings in hectographic ink by restricting the transfer coating to such portions of the transfer sheet where such transfer eii'ect was desired. It is also to be observed that coated transfer sheets were generally adapted for producing a large number of copies and the major portion of transfer ink on such sheets was wasted when only a small number of imprints were taken from the master. This waste was further accentuated by the circumstance that a hectographic transfer sheet had to be discarded after it has 'been used for the preparation of a single master so that the excess not used was thrown away. Although various suggestions and proposals have been made to eliminate these disadvantages and inconveniences of conventional coated hectographic carbon paper, none, as far as I am aware, of these suggestions and proposals was completely satisfactory and successful on a practical scale.

I have discovered an extremely simple and wholly satisfactory solution of the outstanding problem.

It is an object of the present invention to provide a transfer sheet of novel character which eliminates the foregoing disadvantages by placing the transfer ink in the exact position where it is to be used.

It is another object of th present invention to provide a transfer sheet having a transfer surface provided by printing the surface thereof with hectographic transfer ink instead of the conventional coating process.

Still another object of the invention is'to provide a transfer sheet constituted of a sheet-like base bearing printed hectographic transfer material including a vehicle or carrier for color having an affinity for a solvent and being of a nonoxidizing and non-drying character which sets firmly on a surface of a sheet of paper but is capable of transferring to a sheet of paper or the like a deposit of copyable ink when pressure is applied thereto.

A further object of the invention is to provide a transfer sheet constituted of a sheet-like base bearing a restricted area of printed hectographic transfer material and a substantial marginal portion devoid of such material where the sheet may be gripped without soiling the fingers of an operator. 1

It is also within contemplation of the invention to provide a hectographic transfer sheet of great transfer ability bearing printed transfer material, the area, and the thickness of which may be adjusted to the number and the character of the copies desired and which may be manufactured and sold at a low cost.

Other and further objects of the invention will become apparent from the following description taken in conjunction with the accompanying drawing, in which:

, Fig. 1 illustrates a vertical sectional view, somewhat diagrammatic in character, of an apparatus for producing the transfer sheets embodying the principles of the present invention;

Fig. 2 depicts a similar view of the apparatus shown in Fig. 1 with the layer of transfer ink printed on a sheet of paper, the dimensions of the paper and of the printed transfer ink layer being greatly exaggerated for reasons of clarity;

Fig. 3 shows a top elevational view of a transfer sheet embodying the principles of the present invention; and

Fig. 4 is a sectional view taken on line H of Fig. 3 also greatly exaggerated in dimensions.

Broadly stated, according to the principles of my invention, I depart completely from'all prior principles heretofore employed in the production of transfer sheets and provide a sheet having an area of hectographlc transfer ink printed thereon. Of course, as those skilled in the art will readily understand, great variations are possible as to the particular printing process employed in providing such transfer area. It is essential, however, that an ink of such character should be employed which has the property of making a transfer deposit similar to the action of carbon paper, and also has a strong dyeing or coloring quality. Such dyeing or coloring agents can be employed in combination with a suitable vehicle, as will be set forth more fully hereinafter.

I have discovered that it is possible to make 'hectographic carbon paper or transfer sheets of a novel and improved character by a completely cold process without wax in direct contrast to the hot process now in use involving the application of liquefied waxy materials. I prefer to use a semi-fluid viscous ink without dilution by solvents and without the application of heat. I have found that it is possible to make a transfer ink or so-called hectographic carbon ink sufficiently flowing and plastic to be distributed even- 1y by the ink rollers of a conventional commercial printing press and that by applying such ink to a heavy paper of appropriate character, a film of ink is formed thereon which is capable of being transferred under normal pressure, such as handwriting or typing, to another sheet.

Generally speaking, conventional or standard printing ink, which would be incapable of yielding my new results, is a heavy linseed oil varnish combined with driers and carrying solid matter such as a pigment or dyestufl. finely ground to make a uniform plastic mass which when applied to the paper forms a thin color coating thereon. This coating dries by oxidation to form a perfectly dry film which will not offset or transfer when such printed paper is written upon. My new special transfer ink is different from conventional or standard printing nk or carbon paper copying ink in that the base or carrier for color has an affinity for a solvent and is of .a non-oxidizing and non-drying character which sets firmly on its surface but is capable of transferring a deposit of copyable ink when pressure is applied thereto. The affinity of the coloring agent for a solvent is necessary to permit dissolving small amount of the coloring agent in the copyable master by the solvent film on the surface of the copy sheet in the spirit process or by the fluid content of the gelatine in the gelatlne process of duplicating. A printing ink of such special character is capable of carrying a high content of hectographic or copying dyestuif or coloring agent without injuring the stability of the mass which is capable of distribution in its .availas the mass would never become a liquid but would burn before it would liquefy. I

My novel transfer ink adapted to be applied to a sheet-like base by means of printing is essentially constituted'of a fluid viscous mass and of an anti-oxidizing agent added to such fluid viscous mass to provide a vehicle which will carry a high content of dry copying color without in juring the ability of the mass to be distributed on ink .plates or ink rollers in its normal state without heating it. The fluid viscous mass must have the property of carrying a high content of dry, copying color, of spreading smoothly over the rolls and On the ink plates and when transferred from ink plates to paper in an even film. This property of long flow and spread is peculiarly inherent to pure linseed oil varnish. The anti-' oxidizing agent in the vehicle must have the property of combining with the vehicle without turning it into a solid mass and yet imparting to the ink the firmness required for a clean surface and for a transfer or write called a stencil. It must also prevent oxidation of the fluid viscous mass so that a write can be obtained from the printed surface in contrast to the lack of write from a regular printed surface. I prefer to use an ester gum of suitable characteras an antioxidizing agent. A suitable coloring agent or dye is added to the vehicle of the character described. Varlous coloring agents may be employed according to the color desired, provided the coloring agent possesses powerful dyeing or coloring abilityand is soluble in a suitable readily volatilizing solvent, such as, for example, alcohol.-

Satisfactory results are obtained by employing a linseed varnish sold in the trade under the name "pure linseed oil varnish No. 3 forthe liquid portion or the fluid viscous mass. The number denotes the viscosity which may vary from 000 to the most viscous type known as No. 6. I prefer to employ the varnish of No. 3 viscosity in its purest form which is a commercially pure linseed oil varnish and is not adulterated by cheaper ingredients such as wood oil, tung oil, and the like. an ester gum sold under the trade name of "Rosin Ester E. W." which is a polyhydric alcohol abietate. Somewhat similar results may be obtained by means of bleached montan wax as an anti-oxidizing agent which is a soft wax of low melting point and relatively little toughness. To this vehicle I add a suitable coloring agent, such as a dye sold in the trade under the name Crystal Violet Extra," which is the hydrochloride of hexa methyl pararosaniline.

The percentage of the constituents of my novel transfer ink may be varied within fairly wide limits. or varnish may be from about to about by weight, the anti-oxidizing agent or ester gum may be from about 10% to about l7 by weight, the amount of dyestuff depending on the The preferred anti-oxidizing agent is Thus, the amount of the liquid portion from a single copyable'master.

weight. Preferred proportions are about 35% varnish, about 15% ester gum and about 50% crystal violet. In the preparation of the. ink, the rosin ester is dissolved by heating the varnish to 180 Fahrenheit. The mass is then cooled to 120 Fahrenheit and the dye is added.- 'Iheminlsrreis cooled'to Fahrenheit and ground. It isfthen ready for application to the master paper at room temperature or in the so-called cold process. The finished mass is worked smooth in the cold underpressure rollers on the ink plate of the press before being transferred from the printing plate to the base preferably by means of strong, intermittent and vertical pressure. This strong vertical pressure not only greatly consolidates the structure of the layer of ink and strongly bonds the layer to the base by pressing it in part into the absorbent base but, at the same time, provides a relatively tough-skin on the top surface of the ink layer which is greatly resistant to smudging. I generally prefer to provide a sub-.

stantial unprinted area on my transfer sheet preferably on all marginal portions thereof where the sheet can be readily gripped without touching the printed transfer area proper. I have also found that the exact amount ,of ink provided in the printed transfer area can be controlled with great facility and with much greater accuracy -.than it was ever possible with hot coated transin expensive hectographic printing ink. As those skilled in the art know, there are numerous com merclal applications of duplicating forms in insurance companies, banks, brokerage houses, etc., where only a very small number of copies'is made Such copyable masters and their applications are disclosed in my U. S. Patent No. 2,060,190 and in my co-pendlng application Serial No. 269,866, filed April 25, 1939, directed to "Master sheet unit for duplicating records." I prefer to obtain my printedtrahsfer areas by means of one or more printings, depending on the thickness of the layer required. Generally speaking, it is preferred to print a layer of ink about 0.0002" in thickness per impression. A master made from a transfer layer of such thickness provides about 25 clear copies in the spirit process of duplicating. .7hen a largenumber of copies is desired, a thicker layer of transfer ink is provided by means of a plurality of impressions The invention will now be more fully described in connection with the accompanying drawing. Referring now more particularly to Fig. l of the drawing, a diagrammatic view is illustrated indicating the process employed in the preparation of the transfer sheets embodying the present invention. Reference character I denotes the printing surface bearing a layer of transfer ink 2, underheath this printing surface is provided base 3 of It he transfer sheet which is supported by a plane supporting surface I. By displacing printing surface I in the direction of arrows and by applying such surface with strong vertical pressure against base or sheet of paper 3, the layer of transfer ink 2 will be transferred onto the upper surface of such sheet. As will be best observed. from Fig. 2 of the drawing illustrating the printing surface and the transfer sheet after the printing operation, due to the strong, vertical acting pressure, layer 2 of the transfer ink will be strongly bonded to the surface of fibrous base 3 by the circumstance that part of the ink layer will be absorbed by the upper surface of the base. The result is a transfer sheet bearing a printed layer of hectographic ink thereon, such layer having a strongly consolidated structure and having at the top surface thereof a strong skin 8 which is capable of resisting smudging and smearing under all normal conditions.

The general appearance of my improved transfer sheet is depicted in Fig. 3. On a paper base or sheet 1 is provided a printed transfer block 8 covering a restricted area of the transfer sheet. A substantial marginal portion 8 is surrounding the transfer block on all sides, said marginal portions having the object of providing a clear gripping surface which is free from ink and can be conveniently handled by the operator. Of course, these substantial marginal portions also provide great saving in expensive dyestuff. The structure of transfer sheet 1 appears from Fig. 4 of the drawing which clearly shOWS that part of ink layer 8 extends into the body of sheet I and protransfer block proper.

For the purpose of giving those skilled in the art a better understanding of the invention, the

following illustrative example is given:

Example About 17 /2 pounds of pure linseed oil varnish No. 3 free from adulterants such as wood oil, tung oil, etc., are heated to a temperature of about 180 Fahrenheit in a suitable receptacle. After the desired temperature has been obtained, about 7% pounds of a polyhydrlc alcohol abietate,

sold under the name resin ester E. W., are added to the hot varnish and are dissolved therein. The mixture is cooled to a temperature of about 120 Fahrenheit and about 25 pounds of crystal violet extra are admixed. The mixture thus obtained is allowed to cool to 70 Fahrenheit and is ground. After the grinding operation, the thus-produced ink is ready for application to the inking rollers of the printing press at normal or room temperature.

It is to be noted that my novel cold printing process provides a novel hectographic transfer sheet of extremely valuable properties. Thus, I have found that my cold printing process, by not surrounding the dye particles of the ink with a hard, waxy film, permits to use one-third less of the expensive hectographic dyestuff to accomplish the same duplicating work produced by a like thickness of coating of the conventional hot process carbon ink. Inasmuch as the hectographic dyestuff represents of the raw material cost of hectographic ink, the importance of this discovery is obvious to those skilled in the art.

It is also to be observed that by employing a cold printing process instead of the conventional hot coating process, it is possible to provide only restricted areas of the transfer sheet with hectographic transfer ink while other portions thereof-remain clear.

Moreover, the thickness of the printed layer and the content of color therein may be adlusted to the number of copies ultimately desired. Of course, this results in considerable saving in expensive ink since only the areas actually used in the transfer process are provided with an ink layer ofsuch thickness as is necessary for the number of copies to be obtained. I have found that my product may save as much as /2 of the amount of expensive transfer ink and consequently opens up a new field for the application of the spirit duplicating process.

Although the present invention has been described in connection with a preferred embodiment thereof, variations and modifications may be resorted to by those skilled in the art without departing from the principles of my invention. I consider all of these variations and modifications as within the true spirit and scope of the present invention as disclosed in the foregoing description and defined by the appended claims.

The present application is a continuation of my copending application Serial No. 269,865, filed April 25, 1939, as to the subjectv matter in common thereto.

I claim:

1. As a new article of manufacture, a transfer duplicating sheet for the hec'tographic process of spirit duplicating, comprising in combination a base constituted of a sheet of paper and a deposit of hectographic transfer duplicating ink in the form of a non-fusible and plastic mass and applied to said paper with cold pressure, said ink being constituted of a hectographic transfer duplicating coloring agen uniformly distributed in a carrier medium of substantially non-drying and non-oxidizing character comprising a arnish free from drying substances but containing an anti-oxidizing agent to prevent the drying of said carrier medium, said deposit of hectographic transfer duplicating ink being free from conventional heat-fusible, waxy films and oily mediums inhibiting the natural duplicating power of the hectographic transfer duplicating coloring agent and being capable of permanently retaining most of its original plasticity whereby under the effect of pressure a. deposit of hectographic transfer duplicating ink can be transferred therefrom onto another surface to provide a master deposit thereon from which in turn numerous duplicate copies can be obtained by the spirit duplicating process.

2. As a new article of manufacture, a transfer duplicating sheet for the hectographic process of spirit duplicating, comprising in combination a base constituted of a. sheet of paper and a deposit of hectographlc transfer duplicating ink soluble in a readily volatilizing solvent and in the form of a non-fusible and plastic mass and applied to said paper with cold pressure, said ink being constituted of a hectographic transfer duplicating coloring agent uniformly distributed in a carrier medium of substantially non-drying and nonoxidizlng character comprising a. pure linseed varnish free from drying substances but containing a resin ester as an anti-oxidizing agent to prevent the drying of said carrier medium, said deposit of hectographic transfer duplicating ink being free from conventional heat-fusible waxy films and oily mediums inhibiting the natural duplicating power of the hectographic transfer duplicating coloring agent and being capable of permanently retaining most of its original plasticity whereby under the effect of pressure a deposit of hectographic transfer duplicating ink can be transferred therefrom .onto another surface to provide a master deposit thereon from which in turn numerous duplicate copies can be obtained by the spirit duplicating process.

3. As a new article of manufacture, a transfer duplicating sheet for the hectographic process of spirit duplicating, comprising in combination a base constituted of a sheet of paper and a deposit of hectographic transfer duplicating ink soluble in a readily volatilizing solvent and in the form of a non-fusible and plastic mass and applied to said paper with cold pressure, said ink being constituted of a hectographic transfer duplicating coloring agent uniformly distributed in a, carrier medium of substantially non-drying and non-oxidizing character comprising about 30% to about 40% by weight of pure linseed varnish free from drying substances and about to about i.7 of a polyhydric alcohol abietate as an anti-oxidizing agent to prevent th drying of said carrier medium, said deposit of hectographic transfer duplicating ink being free from conventional heat-fusible waxy films and oily mediums inhibiting the natural duplicating power of the hectographic transfer duplicating coloring agent and being capable of permanently retaining most of its original plasticity whereby under the effect of pressure a deposit of hectographic transfer duplicating ink can be transferred therefrom onto another surface to provide a master deposit thereon from which in turn numerous duplicate copies can be obtained by the spirit duplicating process.

4. As a new articl of manufacture, a transfer duplicating sheet for the hectographic process of spirit duplicating, comprising in combination a base constituted of a sheet of paper and a plurality of superposed deposits of hectographic transfer duplicating ink in the form of a nonfusible and plastic mass and applied to said paper with cold pressure, said ink being constituted of a hectographic transfer duplicating coloring agent uniformly distributed in a carrier medium of substantially non-drying and non-oxidizing character comprising a varnish free from drying substances but containing an anti-oxidizing agent to prevent the drying of said carrier medium, said deposits of hectographic transfer duplicating ink being free from conventional heat-fusible, waxy films and oil mediums inhibiting the natural duplicating power of the hectographic transfer duplicating coloring agent and being capable of permanently retaining most of its original plasticity whereby under the effect of pressure a deposit of hectcgraphic transfer duplicating ink can be transferred therefrom onto another surface to provide a master deposit thereon from which in turn numerous duplicate copies can be obtained by the spirit duplicating process, the number of superposed deposits of hectographic transfer duplicating ink on said transfer duplicating sheet correspondin to th number of copies desired from said master.

5. A transfer duplicating sheet of the character set forth in claim 1 in which the hectographic transfer duplicating ink is soluble in a readilyvolatilizing organic solvent.

6. A transfer duplicating sheet of the character set forth in claim 1 in which the deposit of hectographic transfer duplicating ink is proirided only in restricted areas while other portions of the transfer duplicating sheet remain clear.

' A transfer duplicating sheet of the character set forth in claim 4 in which the deposits of hectographic transfer duplicating ink vary in thickness from about 0.0002" to at least about 0.0006" whereby about twenty-five copies to at least about one hundred copies can be duplicated from the master.

WILLIAM D. FOSTER.

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