JPH06102797A - Copy impossible system for copying machine - Google Patents

Abstract

PURPOSE:To accomplish a copy impossible system by a copying machine for preventing securities such as a stock and a bond, etc., important documents such as a contract and a letter of attorney, etc., and confidential documents from being forged by use of a copying machine. CONSTITUTION:The pattern constituted of the design of a prescribed motif, or characters, etc., is printed on the suitable position of a sheet as a copying original 31 by treatment liquid, a watermark having enhanced light transmittivity is formed, and at the time of copying, the difference of the transmitted light quantity between the watermark part and the part other than the watermark part is read by an optical sensor 22 incorporated with the copying machine, and when the prescribed difference is detected, the function of the copying machine is stopped. Thus, the sheet as the copying original 31 is surely detected by the optical sensor 22, and also an inconspicuous watermark is formed, and the copying machine is set so that a copying operation may be stopped when the watermark is detected by the copying machine, then, copied sheets other than the necessary sheets cannot be obtained by forming the watermarks on necessary sheets such as the confidential documents and the important documents.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-copyable system by a copying machine for preventing forgery of securities such as stock certificates and bonds, important documents such as contracts and powers of attorney, and confidential documents by the copying machine. is there.

[0002]

2. Description of the Related Art In recent years, with the spread of copying machines, confidential documents and important documents can be easily copied, and the performance of copying machines has been improved remarkably. Trouble has occurred and it is also a social phenomenon.

In order to solve the above problems, various means have been taken as a method for preventing forgery by a copying machine.

For example, as disclosed in JP-A-54-74125, a method in which a latent image composed of fine constituents is printed on the surface of a substrate and the latent image appears during copying, or JP-A-54-54125. There is known an unauthorized copy prevention device such as forgery of banknotes by a copying machine, which makes a copying operation only when a mark provided on a copying material as disclosed in Japanese Patent Publication No. 36731 is detected.

[0005]

However, in the former method of the above means, the surface of the base material is colored, and when it is used as paper, it becomes difficult to read as a normal document, and It has the drawback of impairing understanding.

On the other hand, in the latter apparatus in which the copying machine is operated only when a mark is applied to the copying material, it is obvious that the copied material is a counterfeit because it has a detection mark. In a normal copying operation, it is necessary to select and feed the copy sheets one by one when feeding, which is very troublesome.

Therefore, the present invention intends to provide a non-copyable system by a copying machine in which a watermark pattern is formed on a sheet of a copy original and the watermark pattern is made special to solve the above-mentioned drawbacks of the conventional example. It is a thing.

[0008]

That is, in the non-copying system of the copying machine of the present invention, a pattern of a predetermined motif or a pattern consisting of characters is printed with a processing liquid at a proper position on the copy original sheet to obtain a light-transmitting property. When a copy is made, the difference in the light transmission amount between the watermark part and the outside of the watermark part is read by an optical sensor incorporated in the copying machine.
The feature is that the function of the copying machine is stopped when a predetermined difference is sensed.

[0009]

Since the non-copying system of the copying machine of the present invention is constructed as described above, the paper of the copy original can be surely detected by the optical sensor and is provided with a less noticeable watermark pattern. Since the copying operation is stopped when the detection is made, it is possible to prevent unnecessary copying from being performed by inserting a watermark pattern in a required number of copies of a confidential document or an important document.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a copy prohibiting system using a copying machine of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 denotes a sheet used as a copy manuscript, particularly securities such as stock certificates, bonds, etc., contracts, and delegations that are misused by forgery of the document by copying. The paper used for the letter corresponds to this. A watermark portion (figure in the figure) 2 composed of characters, figures, patterns and the like is formed as a watermark pattern at appropriate places on the sheet 1.

As a method of forming a watermark pattern on the paper 1, the means described in Japanese Patent Publication No. 25-354 can be preferably used. That is, a pattern consisting of a pattern of a predetermined motif or letters etc. is printed in a suitable place on the paper 1 with the treatment liquid, and the treatment liquid improves the light transmittance of the paper 1,
The watermark portion 2 having the above pattern is formed.

The watermark portion 2 has a light transmission amount of 1.2 to 1.5 times in the wavelength range of 400 to 800 mμ as compared with the unprocessed portion, and has an optical sensor (for example, a laser line sensor manufactured by Matsushita Control Co., Ltd.). LA-500) gives a sufficiently perceptible difference. The following is a comparison of the light transmittance between the normal paper and the watermarked paper.

[0014]

[Table 1] In the above, the numerical values of the blank portion and the watermark portion indicate the amount of light transmission, and the ratio means the watermark portion / blank portion.

The sheet 1 can be used for confidential documents or important documents as described above. that time,
Because of the watermark portion 2, the importance of the document can be fully recognized.

The copying machine to which the above-mentioned paper 1 is applied has a mechanism as shown in FIG. That is, the rotating drum type photoconductor 11, the first charger 12, the light source 13 that irradiates the copy original 31 with light, and exposes the photoconductor 11 through the lens 14, and the exposed photoconductor 11. Developing device 1 for developing
5, a second charging device 16 for transferring to the copy paper 32, a fixing device 17 having a heater, a static eliminator 18 and a cleaning device 19.

The copying machine used in the present invention has a light source 21 mounted at a predetermined position facing a transparent document table.
And a light receiving element 22 that receives the reflected light from the document, and a detection mechanism for the watermark section 2 is provided.

An example of the electronic circuit of the above detection mechanism is shown in FIG. That is, the light source 21, the light receiving element 22 that receives the light from the light source 21, the comparator 23, the CPU 25 transistor 24 that stores the reference value, and the circuit constant setting resistor Ra.
~ Rg, etc. Therefore, the copy original 31 passing between the light source 21 and the light receiving element 22 has the watermark portion 2 on the original placing table.
When the amount of transmitted light at the time of the passage of the value is equal to or larger than the reference value, the detection mechanism operates to urgently stop the copying operation of the copy original.

In the above-described embodiment, the type that detects the reflected light is shown as the optical sensor, but it may be the type that detects the transmitted light, and it may be a type that detects the transmitted light. Various photoelectric conversion materials can be used.

[0020]

Since the non-copying system by the copying machine of the present invention is constructed as described above, the paper of the copy original can be surely detected by the optical sensor and has a watermark pattern which is not so conspicuous. When the watermark pattern is detected, the copying operation is stopped. Therefore, by inserting the watermark pattern in the required number of copies of confidential documents, important documents, etc., it is possible to prevent unnecessary copying.

[Brief description of drawings]

FIG. 1 is a perspective view showing a sheet used in a non-copyable system by a copying machine of the present invention.

FIG. 2 is a sectional view thereof.

FIG. 3 is a schematic view of a copying machine.

FIG. 4 is a block diagram showing an example of an electronic circuit of a detection mechanism.

[Explanation of symbols]

 1 Paper 2 Watermark Part 11 Photoreceptor 12 First Charger 13 Light Source 14 Lens 15 Developer 16 Second Charger 17 Fixer 18 Electrifier 19 Cleaning Device 21 Light Source 22 Photoreceptor 23 Comparator 24 Transistor 25 CPU Ra Rg circuit constant setting resistor

Claims (1)

[Claims] 1. A pattern of a predetermined motif or a pattern consisting of characters is printed on a copy manuscript sheet with a treatment liquid to form a watermark portion with improved light transmittance, and the watermark portion is incorporated into a copying machine at the time of copying. A non-copying system by a copying machine characterized by reading the difference in the amount of light transmission between the watermark portion and the outside of the watermark portion with a light sensor and stopping the function of the copying machine when a predetermined difference is detected.