Method Of Reproducing Predetermined Images

Abstract

A method by which certain material on a master can be reproduced while suppressing reproduction of other material on either the master or copy paper in xerography or like processes. The method uses a master which has the material to be copied printed in light absorbing ink, while the material on the master or copy paper to be suppressed during copying is printed in transparent ink. As examples, the master or copy paper can have background material or instructions printed in colored transparent ink, while the material desired to be reproduced from the master during copying is printed in light absorbing black ink on the master.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to electrophotography copying methods and especially to such electrophotography copying methods which rely on xerographic or light principles.

2. Description of the Prior Art

Electrophotography copying methods, including xerography, are well known and commonly used in the art. Such methods and processes are disclosed, for example, in U.S. Pat. Nos. 2,551,582; 2,357,809; 2,297,691; 2,221,776; 2,573,881; 2,576,047; 2,600,580; 2,618,551; 2,618,522; 2,619,418; 2,638,416; 2,659,670; 2,690,394; 2,725,304; 2,745,327; 2,751,616; 2,772,991; 2,777,957; 2,777,418; 2,808,023; 2,815,330; 2,817,598; 2,817,765; 2,877,133; 2,897,691; 2,951,443; 3,043,686; 3,128,683; 3,244,083 and others.

Xerographic processes in use today normally employ either the direct electrostatic transfer system or the indirect transfer system. In the direct transfer method, the copy paper has an electrostatic charge-receiving coating and light is used to place an electrostatic charge in the form of the indicia to be copied directly on the copy paper coating. The copy paper is then contacted with black toner which adheres to the paper to produce a legible, transferred indicia. In the indirect transfer method, light produces an electrostatic charge from the master on an intermediate element, i.e., a drum surface. Toner is then applied to the drum surface and transferred from the drum surface to a copy paper to produce the copy. In the indirect or drum method the copy paper needs no special coating.

Attempts have been made to produce or reproduce, by xerographic methods, documents having background material and overprinted other material, the background material usually being in lighter or differently colored ink. However, the background material also produces an electrostatic charge which attracts toner during the copying procedure and the background material is reproduced along with the other material. The reproduced background material is much more intense on the copy than on the original and obscures other printed material transferred from the original, whether by the direct electrostatic method or the transfer drum method. For example, it may be desirable to have an automobile owner's copy of his certificate of title look like an original, but when the original is reproduced by xerography methods, the background material comes through far too intensely and obscures other printed material.

The problem of providing a copy which looks like an original has been solved to a small degree by excluding the background material from the original, printing the background material on the copy paper and using the drum type copying machine. This procedure is operable because the image from the master is created on the drum and since there is no background material on the master there is no electrostatic image of background material on the drum. The drum then picks up toner and delivers it to the copy which is preprinted with background material. Such a procedure is successful in providing a copy that looks like an original, but the original must have no background material and cannot itself look like an original document.

However, if the direct electrostatic process is used in such procedure in lieu of the drum transfer process, when the light creates the electrostatic image from the master directly on the copy it will also create an electrostatic image on the copy from the preprinted background material on the copy. When the toner is applied, the preprinted background material shows up black and obscures the copy.

The problem of providing background material on a copy is not restricted to the reproduction of documents. The same problem exists where it is desired to cancel information and/or add information to a document such as an automobile title, an authorized signature check, or the like. For example, it would be convenient in computerized payroll operations to have a plurality of check blank copy papers to which the authorized signature and other printed material and background information may have been preapplied. A computer could receive these check blanks and enter the name of the payee and the amount to be paid for each employee on a separate check blank by xerographic methods, if a way could be found to keep the background material from intensifying during xerography and obscuring desired images.

Additionally, masters, such as original documents from which copies are desired to be produced by xerographic processes, often include background material or other images which need not or should not be reproduced. As pointed out above, such background images obscure the copy and this occurs whether the direct transfer or drum transfer methods are used because the background images, being on the master, are present when the electrostatic image is created and will therefore result in creation of images on the copy.

SUMMARY OF THE INVENTION

This invention provides a method for copying or reproducing predetermined material from a master while suppressing reproduction or intensification of undesired material whether the undesired material be on the master or the copy paper. The invention is especially useful for suppressing reproduction or intensification of background printing which may otherwise be transferred with and obscure the reproduced desired image. The method can be carried out on conventional electrophotographic equipment whether that equipment employs direct electrostatic transfer or drum electrostatic transfer and conventional coated or uncoated electrophotographic copying paper can be used as normally used with such equipment. The master used in the method for making copies includes the material desired to be copied in the form of light absorbing ink on a substrate, usually opaque. The images which are not to be reproduced or intensified are present on the master or copy paper in the form of a nonlight-absorptive ink, usually transparent ink, which provides or permits light reflection substantially equivalent to the light reflection of the substrate as viewed by the electrophotography equipment.

Although this invention is susceptible of embodiment in many different forms, there will be described in detail with reference to the drawings specific examples or embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the examples or embodiments described and illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a master, useful in reproducing copies in accordance with an embodiment of this invention;

FIG. 2 illustrates a piece of xerographic copy paper which has received electrostatic charges during a xerographic process using the master of FIG. 1; and

FIG. 3 is a copy reproduced xerographically from the master of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning first to FIG. 1, a master to be copied by xerography is shown. The master includes an opaque paper substrate 10, having a background design printed thereon in transparent yellow ink 12, and legible printed matter in the form of normal, light absorptive black ink markings 14. The master is used in accordance with the present method to reproduce a copy of the black ink markings 14, without interference from the transparent yellow ink 12. Accordingly, the master of FIG. 1 is subjected to conventional xerographic copying techniques using a copy paper such as illustrated at 16 in FIG. 2. During the copying process, a coated surface 16a of copy paper 16 receives and retains an electrostatic charge, as shown in phantom at 18 in the form of the light absorptive markings 14 on the master. Because the background material printed in yellow ink is transparent, as seen by the xerographic machines, the light passes through ink 12 and reflects from the substrate surface 10 so that ink 12 does not create an electrostatic charge on surface 16a. This eliminates transfer of the unwanted background material and is especially useful in direct electrostatic transfer xerography.

The electrostatic charges 18 attract a black toner or like powdery material, during the xerographic process, to form images 20 (FIG. 3) on the copy paper 16. The images 20 correspond to the black ink markings 14 on the master.

The present invention also is capable of producing copies which look like original documents from a master which may or may not look like an original document. Referring again to FIGS. 1 through 3, the copy paper 16 includes preprinted background material printed in colored transparent ink as indicated at 22. During the copying procedure, the background material 22 does not create an electrostatic charge and does not receive toner except where an electrostatic charge has been created by the printed matter 14 on master 10. Thus, the resultant copy, as seen in FIG. 3, retains the background material 22 without intensification.

Any combination of eliminating the transfer of background material or providing a copy with additional background material can be carried out using transparent ink for printing the material which is not to be transferred and/or for printing the copy paper with background material which is not to be affected by the xerography process. By combinations of the deletion of background material 12 from the copies and the preprinted addition of background material 22, the present invention can be used to delete or add material by simple xerographic procedure. For example, masters can be printed with transparent ink to indicate to an operator of a xerographic machine precisely where to position the master during reproduction, especially if material is to be reproduced on a copy in a position which differs from its position on the master. As a more particular example, columns of figures can be shifted on a copy, the name of a transferee or a deed or title can be shifted into the position of a transferor and the previous transferor on the master can be deleted. Identical copies can also be produced by printing the same background material on both master and copy paper using the same transparent ink. For example, if the copy paper 16 in FIGS. 2 and 3 had been preprinted with the same background material 12 in the same color of transparent ink as appears on the original 10 in FIG. 1 and in the absence of background material 22 on copy paper 16, the finished copy in FIG. 3 would be identical to the original in FIG. 1.

The master substrate can be any opaque material, usually paper. The nonreproducible material, e.g., the background material, is formed on the substrate with transparent ink, usually containing oil-soluble colors such as the acid and basic dyes in a suitable transparent carrier or vehicle. The background material ink can have light absorbing properties, but these properties should not be materially greater than those of the substrate surface. Such ink is transparent as viewed by a xerographic machine, but is visible to the human eye and is usually visible only into the near infrared range.

Xerographic processes and copy papers which are useful in carrying out the present invention are conventional in the art. In drum transfer methods uncoated paper is ordinarily used while the direct electrostatic method requires coated copy paper. Reference is made to the patents identified in the discussion of the prior art, above, relating to xerographic processes for suitable processes and copy papers, and the description of those patents is incorporated herein to the extent that such processes and papers are described. The same transparent inks can be used to preprint the copy paper with any background materials which are not to be blackened or intensified during the copying procedure.

Light absorptive inks are commonly used in printing xerographic masters, e.g., official documents and the like. Although transparent inks are not as common as the light absorbing printing inks, many are known to the art, for example as described in U.S. Pat. Nos. 2,567,963; 2,567,965; 2,772,983 and 2,796,415. The dye in the ink should be light stable so that its color does not change as a result of being subjected to the xerographic process. Suitable transparent inks have been prepared, for example, using Auramine yellow basic dye (a triphenyl methane-type dye) or red or blue acid dye in a transparent ink vehicle, such as bodied linseed oil varnish, cyclicized rubber resin adjusted to proper viscosity with a solvent such as flash oil (e.g. Magie Oil), or esters of dimeric resin acids in flash oil or other solvent. In preparing a master, it is preferred that any transparent ink background material, e.g., at 12, be printed first and that the photoreproducible material, e.g., at 14, be printed over the background material.

The following examples are offered for the purpose of further illustrating the invention, but are not intended as limitations on the invention.

Examples 1 through 3

Three samples of transparent ink were prepared using an oil soluble Auramine 0 basic yellow dye at about a 25 percent level in each of the following vehicles: ---------------------------------------------------------------------------

Ink Sample No. Vehicle __________________________________________________________________________ 1. bodied Linseed Oil 2. 40 wt.% Alpex 44-400 (Cyclicized Rubber Resin) in Magie Oil 3. 50 wt.% Pentalyn K (Pentaerythritol Ester of Dimeric Resin Acids) in Magie Oil __________________________________________________________________________

The three ink samples were proofed on a Vandercook Proof Press on a white xerography copy paper to form transparent yellow images such as shown at 22 in FIG. 2. After drying, the copy paper was used in a xerography process to reproduce thereon the printed material 14 from the master 10 in FIG. 1. The yellow background material 22 appeared the same on the finished copy as it did on the original copy paper and an image was produced over the yellow background material from the printing on the master.

Examples 4 and 5

Example 1 was repeated using oil soluble Lacarno pink dye (triphenylmethane basic dye) and Phthalocyan blue dye (monastral blue), for examples 4 and 5, respectively, in lieu of the yellow dye used in example 1. Similar results are obtained from the xerographic copy method.

Examples 6 through 8

The three inks were proofed on a Vandercook Proof Press on a white paper substrate to form transparent yellow images, such as shown at 12 in FIG. 1. After drying, the background material was then overprinted with reflective black ink to produce legible markings thereon and the sheets were again permitted to dry. When the resulting masters were used in a direct electrostatic transfer xerographic process for reproducing copies, the background material printed in the transparent yellow ink did not reproduce and only the reflective black ink markings appeared on the copy.

Examples 9 and 10

Example 6 was repeated using oil-soluble Lacarno pink dye (triphenylmethane basic dye) and Phthalocyan blue dye (monastral blue), for examples 9 and 10 respectively, in lieu of the yellow dye used in Example 6. Similar results are obtained from the xerographic copy method.

Transparent inks utilizing still other vehicles have also been investigated and found to be suitable. For example, other heat setable vehicles such as a mixture of phenolic resin or esterified resin in flash oil can be used; heat setable inks are dried by using heat to drive off the solvent portion, e.g., the flash oil. Drying vehicles such as a varnish containing alkyd resin in linseed oil with cobalt or manganese driers, gravure ink lacquer such as nitrocellulose in solvent and plasticizer or the like. Also combinations can be used such as alkyd resin varnish plus a phenol-formaldehyde resin, usually high molecular weight, and flash oil. The dye can conveniently be dissolved in an oil or other solvent prior to mixing it with the vehicle. Since soluble dyes, not insoluble particular pigments, are used, there are no problems with respect to wetting out, mixing or dispersion.

Claims

We claim:

1. A photo reproduction method for reproducing selected images upon a copy sheet from a master while suppressing reproduction of predetermined nonselected images, which method comprises preparing the master with selected images printed with visible-light-absorptive ink on an opaque substrate, printing at least one of the copy sheet and opaque substrate of the master with visible-nonlight-absorptive ink to form nonselected images and then photocopying the master selected images upon the copy sheet whereby a copy is produced of the selected images in substantial absence of reproduction of nonselected images.

2. A photo reproduction method for reproducing selected images upon a copy sheet from a master while suppressing reproduction of predetermined nonselected images, which method comprises preparing the master with selected images printed with visible-light-absorptive ink on an opaque substrate, preparing the copy sheet with nonselected images printed with visible-nonlight-absorptive ink, and then photocopying the master selected images upon the copy sheet which already contains the nonselected images whereby a copy is produced of the selected images in substantial absence of reproduction of said nonselected images.

3. The method of claim 1 or 2 wherein the master is printed with the nonselected images in transparent ink.

4. A xerography method for reproducing selected images upon a copy sheet from a master while suppressing reproduction of predetermined nonselected images which method comprises preparing the master with selected images of flexible light-absorptive ink on an opaque substrate, preparing at least one of the copy sheet and opaque substrate of the master with nonselected images of visible-nonlight-absorptive ink, and the providing an electrostatic image by differences in light reflectivity from the master to the copy paper which retains the electrostatic change in the form of the image to be produced for attracting darker toner material in the form of the image to the copy paper, whereby a copy is produced of the selected images in substantial absence of reproduction of said nonselected images.

5. The method of claim 1 wherein said nonlight-absorptive ink is transparent ink and comprises a vehicle selected from the class consisting of bodied linseed oil varnish, cyclicized rubber resin and esters of dimeric resin acids.

6. The method of claim 5 wherein said ink includes auramine dye.

7. The method of claim 5 wherein said vehicle is bodied linseed oil varnish.

8. The method of claim 1 wherein said nonselected images define background material printed in transparent ink on said master and said selected images are printed over said background material with nontransparent-light-absorptive ink.

9. The method of claim 8 wherein the transparent ink and light-absorptive ink are of visual appearances differing from each other.

10. The method of claim 9 wherein said transparent ink is colored and said light-absorptive ink is black.