JPH0239185A - Copying sheet - Google Patents

Abstract

PURPOSE:To prevent the leakage of secret due to recopying by enclosing an arbitrary area with continuous recognizing lines (erasure lines) by means of an image reading sensor and forming plural segments in that area. CONSTITUTION:An arbitrary area on a copying sheet S is enclosed with the continuous erasure lines LL, and erasure lines LL1 to LL4 partition the area to form two or more segments. A group in a company, etc., having a digital copying machine that can perform trimming copying and masking copying, sets a switch to a trimming copying mode, for instance. As long as a user marks information that he would like to keep secret in a frame of a specific density formed on an original and on the sheet S used as transfer paper, a copy of the information cannot be taken as an image even someone tries to copy it. Thus, the leakage of secret due to recopying can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a copy paper that can be used as a manuscript for copying or as a transfer paper for copying.

[Conventional technology]

With the spread of copying machines, many years have passed since the publishing industry began to make frequent calls to strictly prohibit the reproduction of originals due to copyright claims.

Recently, from the viewpoint of preventing leakage of confidential information, requests have been frequently made from government offices and general companies for the creation of paper that cannot be copied again.

In order to meet these demands, the following method (1) intertwining halftone dots with the background pattern and using the resolving power of the copying machine to spread out or not spread out the halftone dots makes the hidden characters stand out. method.

In this method, when a copy is made, the characters and patterns appear, which is very effective in warning against illegal copying and preventing forgery, but on the other hand, the original characters can still be read.

(2) A method in which a special ink or paint is mixed with pulp or coated (or printed) on copy paper, and this ink (paint) changes the reflective characteristics of the paper, causing the entire surface to appear black when copied. .

In this method, the paper surface coated with ink (paint) is colored brown, making it difficult to read the text on the document itself, and depending on the copying machine, it may be completely unreadable.

(3) Overcoat the paper used as a manuscript by vapor-depositing aluminum and applying a coloring agent on top of it, or in the case of film, applying a coloring agent to the front surface and vapor-depositing aluminum to the back side, so that the halogen light from the copying machine becomes mirror-like. A method that makes copying impossible by reflecting the light.

Disadvantages of this method include that it is difficult to see the text on the original, that it cannot be used as transfer paper for copying, that it is not effective for documents created with dot printers or typewriters, and that it is more expensive than other methods. There is.

[Problem to be solved by the invention]

All of the above conventional methods utilize the optical characteristics of a copying machine, and the problem is that the original document to be recopied must be extremely difficult to read, ignoring human readability. there were.

On the other hand, in recent years, so-called digital copying machines, which have a mode that allows the document image to be erased within or outside an area surrounded by a line (hereinafter referred to as an erasing line) with density and thickness that can be identified by a single image reading sensor, have been introduced. As copying machines became more and more popular, I came up with the idea that by using the functions of such copying machines, it would be possible to effectively erase images when recopied without impairing the legibility of originals. Ta.

Therefore, a digital copying machine capable of detecting an area surrounded by a frame of a specific density and performing trimming copying to erase the inside and masking copying to erase the outer area was proposed in Japanese Patent Application No. 1518/1989 ( This was proposed in Japanese Patent Application Laid-Open No. 159570/1983).

That is, it is possible to erase a specific area in the scanner reading of a document and the digitization process of the read information, which is a feature of a digital copying machine, by defining the operation mode for a certain designated signal, and this function is utilized.

Accordingly, one object of the present invention is to provide copying machine paper which, in combination with the functions of a copying machine, can prevent secret leakage due to recopying without impairing the readability of the original.

[Means to solve the problem]

In order to achieve the above object, (1) in the copying machine paper of the present invention, an arbitrary area is continuously surrounded by an unbroken erasing line, and within this enclosed area, two or more areas are further formed. It was decided to partition the area with the eraser inn so that it could be done.

[For production]

The erasing line made on the paper is read by an image reading sensor, and the area inside or outside the area surrounded by the erasing line is not reproduced as a picture area through digital processing.

〔Example〕

First, a first example of a digital copying machine suitable for carrying out the present invention will be described.
This will be explained using Figure 0.

Reference numeral 41 indicates a part of the scanner, and an image of a document 42 is converted into an electric signal by a solid-state image carrier (CC:D) 43 via a mirror M11 Mz HMz and a lens L.

The image a signal thus obtained is processed by the image signal processing section 44.

Reference numeral 45 indicates a printer section, which is connected to a laser diode drive section 46 through a signal line.

The laser diode drive unit 46 drives a laser diode 47 using the image signal processed by the image signal processing unit 44, and the laser light generated by one emission is transmitted to a polygon mirror 48,
The photoreceptor 50, which has been charged in advance by the charger 49, is exposed through the mirror M4. As a result, an electrostatic latent image corresponding to document information is carried on the photoreceptor 50.

The electrostatic latent image thus carried on the photoreceptor 50 is transferred to the developing section 5.
1, and is transferred to a transfer paper fed from a transfer paper cassette 52 or a transfer paper cassette 53 at a transfer unit 54.

Thereafter, the transfer paper is ejected to a paper ejection tray 56 via a fixing section 55.

Next, according to FIG. 11, the control section 5 of the digital copying machine
7 and the operation section 58 will be explained.

Reference numeral 59 indicates a copy start key, 60 a numeric keypad for inputting the number of copies, 61 a copy number display, 62 a trimming copy instruction key, and 63 a masking copy instruction key.

The trimming copy instruction key 62 and the masking copy instruction key 63 are mutually exclusive, and if one is pressed and then the other is pressed, the instruction of the former becomes invalid. Furthermore, pressing the same key again will cancel the instruction.

Reference numerals 64 and 65 indicate LEDs that light up when trimming copying and masking copying are instructed, respectively.

Reference numeral 66 indicates a switch provided at a location other than the operating section 58 and which cannot be operated by a general operator. It does not function particularly when the lever 67 is at the neutral point, but the terminal 68
When the trimming copying instruction key 62 is pressed, trimming copying is instructed.

Further, when connected to the terminal 69, masking copying is instructed in the same way as when the masking copying instruction key 63 is pressed. At this time, the LEDs 64 and 65 light up according to each instruction.

Moreover, when any one is instructed by the switch 66,
Trimming copy instruction key 62. Pressing the masking copy instruction key 63 becomes invalid.

Therefore, if a group such as a company equipped with such a digital copying machine sets the switch 66 to, for example, trimming copying mode, the user can make copies as long as the information they wish to keep confidential is written within a certain density frame on the paper. Even if you do, the image will not come out, so in that sense it is a measure to prevent secret leaks.

The above-mentioned measures to prevent leakage of secrets can be effectively achieved by setting a frame with a specific density on the paper for the digital copying machine, that is, the paper used as a manuscript and the paper used as a transfer paper.

Some usage examples will be explained with reference to FIG.

It is assumed that a document S1 is a sheet of paper without any frame of a specific density, and information A is written on it.

On the other hand, the paper S2 is provided with an erasing line LL, which is a line of density and thickness that can be identified by the CCD 43, which is an image reading sensor of the digital copying machine.

If this paper S2 is used as a transfer paper and a copy is made in the normal mode with a digital copying machine, the information A is transferred to the erasing line L.
The sheet S'2 contained in L can be obtained.

If this sheet s+2 is used as a document, the information A will not appear on the transfer sheet S when it is recopied using a digital copying machine set to the trimming copying mode.

Therefore, if confidential information is written on general paper and you want to copy it in large quantities as meeting materials, if you have paper S2 on which the erasure line LL has been printed in advance, you can quickly copy and prevent re-copying. A manuscript (sheet S'2) having the following information can be created.

Alternatively, you can use paper S2 from the beginning and enter confidential information A on it.
If you write , 29 immediately becomes a manuscript (sheet S"z) that has a function to prevent re-copying. Therefore, use this paper Sl'z as a manuscript and copy it with a digital copying machine set to trimming copying mode. However, information A does not appear on the transfer paper S3.

As described above, it is extremely convenient to form the erasure line LL in advance on the paper used in a digital copying machine as a manuscript or transfer paper in order to prevent secret leakage.

In FIG. 9, if a normal transfer paper without erasing lines is used for copying, information A will appear on the paper S4. Furthermore, even if you recopy this, as long as you use regular transfer paper,
Information A appears on the paper Ss.

The erasing line LL is formed as a closed rectangular frame at the outer edge of the paper as shown in FIG.

This is because information can only be written within the area of the paper, and enclosing the information in a continuous, unbroken line is a requirement for the digital copying machine to perform its trimming or masking function.

However, there are still some inconveniences.

If the original is set and copied in such a way that part of the outer frame consisting of the erasing line is intentionally removed from the reading area of the CCD 43, the erasing line does not surround confidential information with a continuous line. This is because the information is copied even though it is in trimming mode.

To avoid this inconvenience, the area surrounded by the outer frame may be partitioned off with erasing lines so that two or more areas are created.

FIGS. 1 to 7 show specific aspects thereof.

In the example shown in FIG. 1, the erasing line LL1 is
The outer frame consisting of the erasing line LL is divided into two.

In this case, even if one area is copied by slightly shifting the document made of paper S from the platen of the digital copying machine, that part will not be copied as long as the other area is surrounded by the erasing line. Not done.

In the example shown in FIG. 2, a large number of concentric erasing lines LL
The outer frame is divided into multiple parts by 2.

In this case, there is an advantage that the copy of the secret information may have missing portions in various unpredictable ways that follow a single curve depending on how the document is shifted.

In the example shown in FIG. 3, the outer frame is divided into multiple parts using a large number of small circular erasing lines LL that touch each other.

In the example shown in FIG. 4, a large number of small circular erasing lines LL4 spaced from each other form a large number of areas within the outer frame. By disarranging the arrangement of the small circular areas in a staggered manner, the aim is to disturb the reproduced information.

The example shown in FIG. 5 is based on a rectangular shape made up of erasing lines LLs, and on top of this, stepped erasing lines LLs made of thin lines are used.
, to subdivide the area and at the same time aim to create an effect that is visually easy to see. The enlarged state is shown in FIG.

In the example shown in FIG. 7, a large number of serrated erasing lines LLa are orthogonal to the parallel line consisting of the erasing line LL-1 to form a large number of areas within the outer frame.

FIG. 8 shows this in an enlarged manner, and the thin line 70 drawn halfway between each capitula is aimed at visual effects such as ease of viewing. Various other aspects are possible.

It is desirable that each of the erasing lines described above be as indiscernible to the human eye as possible, even if it is readable by the CCD 43.

The thickness, a degree, color characteristics, etc. of the line used as the erasing line are appropriately determined based on the human visual characteristics and the reading characteristics of C0D43.For example, a line thickness of 2+nm and a density of 0.6 are sufficient. Admitted.

The erasing line formed inside the outer frame is related to the function of the digital copying machine, and the size of one of the plurality of areas is, for example, formed to the maximum area that can make the information unreadable.

〔Effect of the invention〕

By using the paper according to the present invention, it is possible to easily create a manuscript for copying that can prevent leakage of secrets due to re-copying without impairing readability.

[Brief explanation of the drawing]

1 to 5 and 7 are respectively front views of copying machine paper according to the present invention, and FIG. 6 is a partially enlarged view of FIG.
Figure 8 is a partially enlarged view of Figure 7 above. FIG. 9 is a diagram illustrating various processes for making copies using paper etc. according to the present invention, and FIGS. 10 and 11 are schematic explanatory diagrams of a digital copying machine suitable for carrying out the present invention. S...Paper, LL, LLt-, LLz, LL3-
LLa, LLs, LLG... Lines for erasing. gourd

Claims (1)

[Claims] A sheet of paper used in a copying machine that has a mode capable of erasing a document image within or outside an area surrounded by a line of density and thickness that can be recognized by an image reading sensor (hereinafter referred to as an erasing line). , an arbitrary area is continuously surrounded by unbroken erasing lines, and is further partitioned by the erasing lines so that two or more plural areas are created within the enclosed area. A copy paper characterized by: