JPH02253286A - Copy preventing paper - Google Patents

Abstract

PURPOSE: To provide copy preventing paper having a high copy preventing function, easy operability and excellent readability by using translucent paper of which surface is colored by blue black or green black and rear face is colored by yellow or fluorescent yellow. CONSTITUTION: Translucent paper of which surface is colored by blue black or green black (e.g. ink containing pigment having 470 to 490nm absorption main wavelength is applied) and rear face is colored by yellow or fluorescent yellow so that the reflection rate of a visible part is <=5% is used as copying paper. When the contents of a document to be distributed are copied by black toner by the use of an electronic copying machine, a document of which contents can be easily and visually read out but cannot be copied can be prepared. The visual reading of the contents can be more easily attained by providing the rear face of the copy preventing paper with a means capable of reflecting incident light to the surface of the paper and scattered light in a room.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a copy-preventing paper whose contents cannot be copied by an electronic copying machine but whose contents can be easily read visually, and further improves readability. The present invention relates to a reading method using a paper or plastic sheet capable of reflecting incident light and scattered light on the back side of the paper.

[Prior Art 1] In today's world where information can be easily reproduced, it is extremely important to be able to prevent copying of important documents.

Conventional methods to prevent copying include coloring paper, printing camouflage patterns on colored paper, or pasting a plastic film processed to make copying onto the surface of the document. etc. are known. However, these methods have problems such as not necessarily having sufficient copy protection functions, requiring complicated pasting operations, and making it difficult to understand the content, so none of these methods is still satisfactory. The current situation is that this has not yet been achieved.

[Problem to be solved by the invention]

Therefore, the present invention eliminates the problems of the prior art described above,
It is an object of the present invention to provide copy-preventing paper that has a high copy-preventing function, is easy to operate, and has excellent readability.

1 Means for Solving the Problem 1 The anticopy paper according to the present invention is made of translucent paper whose front surface is colored blue-black or green-black and whose back surface is colored yellow or fluorescent yellow.

According to the present invention, as described above, the reflectance in the visible region is 5.
% or less, the surface is colored blue-black or green-black (for example, coated with ink containing a pigment with a dominant wavelength of 470 to 490), and the back side is colored yellow or fluorescent yellow. By copying the contents of a document to be distributed using black toner using an electronic copying machine, it is possible to create a document whose contents are easy to read visually but cannot be copied.

In addition, making it easier to visually read the content is
This can be achieved by providing a means on the back side of the copy-preventing paper to reflect the progenitor light and indoor scattered light to the surface of the copy-preventing paper. Such methods include (1) a method of overlaying fluorescent yellow colored paper or plastic sheet directly or at arbitrary intervals on the back side of anti-copying paper;
(2) A method of stacking paper or plastic sheets laminated with mirror-glossy metal foil directly on the back side of anti-copying paper at regular intervals is economical and easy to operate. There is also a method (3) of using planar illumination by electroluminescence, but this is not a desirable method because it is expensive and requires a power source.

FIG. 1 shows a reflectance curve in the visible region of a translucent paper used in the present invention whose front side is colored blue-black or green-black and whose back side is colored yellow or fluorescent yellow. In Figure 1,
The curve is the reflectance curve of blue-black colored paper, and the curve 2 is the reflectance curve of green-black colored paper. As shown in Figure 1, all of these papers have a reflectance of 5% or less, so if a document is copied using black toner on the surface of this paper using an electronic copying machine, it will be difficult to reproduce the paper from this paper. Copying is not possible.

Moreover, since these sheets themselves are translucent, their contents can be easily read if the light transmitted from the back side is used.

When the anti-copy paper according to the present invention is bound thickly, paper or plastic sheets colored with fluorescent yellow or white, metal sheets with specular luster, or paper or plastic sheets laminated with metal foil are used to bind the paper. By effectively utilizing the Taejo light and the scattered light by superimposing it on the back side, it is possible to easily read and read the recorded contents of the anti-copy paper according to the present invention.

As the translucent paper used for the copy prevention paper according to the present invention, commercially available products such as Mitsubishi Paper Dx Trace can be used.

〔Example〕

Hereinafter, preferred embodiments of the copy prevention paper according to the present invention will be explained in more detail according to Examples, but it goes without saying that the technical scope of the present invention is not limited to these Examples.

1. As shown in Figure 1, a blue-black offset ink [Toyo Ink CF34661] was applied to the surface of a semi-charcoalized paper so that the reflectance in the visible area was 5% or less, and dried. Next, fluorescent yellow offset ink [Toyo Ink CF3676] was applied to the back side and dried.

When recording was made on this using black toner from an electronic copying machine, it was easy to visually read the content, but it was impossible to recopy.

1 fl In the same manner as in Example 1, green-black offset ink [Toyo Ink CF3469] was applied and dried so that the reflectance in the visible area was 5% or less as shown in Figure 1.
Next, on the back side, fluorescent yellow Offset Shito Ink 1 Toyo Ink Q! 1cF8676] was applied and dried.

When recording was performed on this using black toner from an electronic copying machine, the resulting recording paper was easy to visually read, but it was impossible to recopy.

Tip 1 The copied paper obtained in Example 1 has the following on the back side:
When a fluorescent yellow offset ink (Toyo Ink@CF3676) was coated and dried on white paper, the visual readability was further improved. It was particularly effective when the paper inclined at an angle of 60 degrees or more with respect to the horizontal.

In Uragotando Example 3, when paper printed with fluorescent yellow offset ink (Toyo Ink CF3676) was embossed into a sawtooth bundle with a width of 2 to 3 mm, the difference between the paper and the recording paper was used. The readability was slightly improved compared to Example 3 because the small gap made it easy to use the scattered light inside the room.

When the mirror-glossy aluminum foil laminated to the paper was used on the back side of the paper obtained in Ura-Pilgrimage Example 1, the visual readability was further improved. It was particularly effective when the paper was in a horizontal position.

As shown in Figure 1, blue-black offset ink (Toyo Ink CF3466) was coated on the surface of a semi-transparent paper so that the reflectance in the visible part was 5% or less, and then dried. Next, on the back side, use yellow offset ink [Toyo Ink QsjJcF
8208] was applied and dried. When we recorded on this using black toner from an electronic copying machine, the content was easy to read visually, but it was impossible to recopy.

[Brief explanation of drawings]

FIG. 1 shows the reflectance curve of the visible part of anti-copying paper. 1--------One blue black colored paper 2-・-・-green-black colored paper

Claims (1)

[Claims] 1. Copy-prevention paper made of translucent paper colored blue-black or green-black on the front side and yellow or fluorescent yellow on the back side. 2. A method for deciphering information recorded on paper or plastic sheets with fluorescent yellow or white coloring applied to the back side of the anti-copying paper according to claim 1, either directly or at an arbitrary interval. 3. A method for reading information recorded on sheets of paper or plastic sheets, which are laminated directly or at arbitrary intervals, in which a metal foil with specular luster is pasted on the back side of the copy-prevention sheet according to claim 1.