JPS5923999B2 - printed matter - Google Patents

Description

[Detailed description of the invention] The present invention is characterized in that the color tone and pattern change due to ultraviolet irradiation,
Moreover, it concerns printed materials whose patterns are difficult to tamper with.

Conventionally, various attempts have been made to prevent forgery of printed matter such as securities and lottery tickets.

The most common practice is to use high-quality printing technology that cannot be imitated anywhere else.

For example, a printing method called Sammel letterpress is used.

In this method, several different colors of ink are applied to each color separation plate, transferred to an elastic collection cylinder (Sammel cylinder), and then the inks are applied to the printing plate to print in multiple colors on the printing material at once. It is something.

Since each color of the image is printed at the same time, the ink color can be changed without cutting the image line, so printing can be performed without any deviation in register accuracy.

However, this method has the disadvantage that plate making and printing costs are high.

In addition, special machine engravings, hand engravings, etc. are used to create plates that cannot be imitated anywhere else, and to prevent counterfeiting by printing.

However, this resulted in a very high plate-making cost.

Furthermore, there are drawbacks common to methods using the above-mentioned Sammel letterpress printing method and methods using special machine engraving, hand engraving, etc.

In other words, due to recent advances in photography and printing technology,
If the printed matter is photographed, copied, and forged, it becomes difficult for even experts to determine its authenticity, and the general public has the disadvantage that it is difficult to determine its authenticity.

If these securities were to be destroyed in a fire, even experts could not determine their authenticity.

In addition, there are some printed items such as checks that use ink whose color disappears or changes color when erased, and printed items that use ink that disappears when erased, but these color changes are irreversible and once Once it was inspected for authenticity, it could no longer be used as a product.

Furthermore, if it was burned, even experts could not judge whether it was true or false.

In addition, a pigment obtained by pulverizing a solid obtained by dissolving an organic fluorescent dye in a resin at an appropriate concentration is dispersed in a vehicle. Although there are attempts to use optical ink,
This is not suitable for preventing counterfeiting of securities since it does not have light resistance (6 months at most).

That is, depending on the storage conditions, if the material stops emitting fluorescence after about 6 months after printing, the real product will become a fake, and in the case of securities, semi-permanent durability is desired.

Furthermore, once it was burned, it was impossible for even an expert to judge whether it was true or false.

The present invention solves all of the above-mentioned drawbacks, and its main purpose is to provide printed matter whose color tone and pattern change upon irradiation with ultraviolet rays, and whose pattern is difficult to tamper with.

That is, in the present invention, a pattern layer consisting of a transparent ink in which a colorless transparent or white inorganic phosphor having a refractive index equal to or similar to that of the vehicle resin is dispersed is formed on a pattern layer consisting of a colored ink. This is a printed matter characterized in that it is printed on a support so that at least a portion thereof overlaps.

Next, the present invention will be explained in detail.

In the printed matter of the present invention, a colored pattern is first printed on a support such as natural fiber paper or synthetic paper using colored ink.

Colored ink is one in which colorants such as pigments and dyes are dispersed in a vehicle, and is colorless or exhibits a hue other than white under white light such as incandescent light, fluorescent lamp light, or sunlight. It is.

This colored pattern may be formed by a general printing method similarly to the transparent pattern described later.

A transparent pattern is formed on the colored pattern using a transparent ink having the composition described below so that at least a portion of the transparent pattern overlaps with the colored pattern.

The transparent ink constituting the transparent pattern is one in which a colorless transparent or white inorganic phosphor having a refractive index the same as or similar to that of the vehicle resin is dispersed in a vehicle resin.

Generally, a colorless transparent or white pigment with a relatively low refractive index is placed in a vehicle resin so that the refractive index of this face and the vehicle resin is the same or similar, and when the two are kneaded together, it becomes transparent or translucent ( transparency).

Therefore, the transparent ink also becomes transparent, and the presence of the transparent pattern on the support becomes difficult to recognize under white light.

However, since there is inevitably a difference in reflectance between the transparent pattern and the underlying support, the transparent pattern cannot be completely recognized on the support, and the transparent pattern made of transparent ink cannot be completely recognized on the support. Printed matter with this pattern gives a strange feeling that the pattern appears to be printed but cannot be clearly seen, which is not desirable.

However, the printed matter of the present invention is printed on a support by a normal printing method so that a pattern made of transparent ink and a pattern made of general colored ink partially overlap, so the printed matter is made of colored ink. The human eye is fooled by colored patterns, and under white light only colored patterns can be seen, and the strange feeling described in the description disappears.

In the printed matter with the above configuration, the transparent pattern emits light when irradiated with ultraviolet rays, but since the transparent pattern is provided so that at least a part of it overlaps the colored pattern, there is a part with only the transparent pattern and a part with the colored pattern. The hue of the chisel part and the part where each of the above-mentioned patterns overlap are all different, and a colored pattern that is different from the pattern recognized under white light can be recognized, creating an excellent hidden printing effect. become.

Furthermore, since this printed material has a transparent pattern located on the top layer, the fluorescent color emitted by ultraviolet irradiation becomes very bright and has the following effects.

In other words, when altering a colored pattern, the transparent pattern placed at the top must also be altered, but the transparent pattern, which is observed in a transparent or nearly transparent state under white light, can be restored to its original state. It is very difficult to do so, but if you irradiate it with ultraviolet light and observe the presence of inorganic phosphors and the connection between the transparent pattern on the colored pattern and the surrounding transparent pattern, you can instantly find out that it has been tampered with. become.

According to the present invention, the following effects are further achieved.

(1) Using an inexpensive and easy-to-use ultraviolet irradiation device, the color tone changes instantly when irradiated with ultraviolet light, making it easy for the average person to determine authenticity.

(2) Since the changes in the printed matter are reversible, the printed matter can be used again even after the authenticity test.

(3) Light resistance is semi-permanent since it is an inorganic substance.

(4) Even if the printed matter burns and turns to ash, the phosphor is inorganic and will not be affected by that level of heat; it will emit light when exposed to ultraviolet rays.

Therefore, even if it burns to ashes, ordinary people can easily and instantly determine its authenticity.

(5) Since the present invention does not restrict printing methods in any way, conventional printing techniques for securities can be used.

The present invention is useful for preventing counterfeiting of securities, and securities include stock certificates, corporate bonds, gift certificates, checks with face value, lottery tickets, gift certificates, air letters, postal letters, and famous people with face value. certificates, stamps, revenue stamps, checks, bills, certificates,
Credit cards, ID cards, insurance certificates, warehouse certificates,
It refers to exchange tickets, lottery tickets, membership tickets, guarantees, bankbooks, dividend amount receipts, securities slips, labels, stickers for approval and regulation purposes, Lotus Pon products, slips, etc.

In addition, the present invention has light resistance when used in a display.
This produces very interesting effects.

Examples are described below.

Example l ・Toppan Bureau paper light cream == (Gin J-Hata Seisakusho 13
8? /d), solid printing was performed using TKUG yellow manufactured by Toyo Ink Seisakusho.

Next, a pattern of -TOPPAN= was offset printed on the solid printing area using an inorganic fluorescent ink having the composition shown below and kneaded using a three-roll roll.

Under fluorescent light, the ==TOPPANj= pattern cannot be discerned and only a solid yellow print is visible, but PANUVLA
When UV rays were irradiated using MP PUV-IA (@Tokyo Kogaku Kikai Co., Ltd.), a bright red-orange =-TOPPAN== pattern emerged.

This change was reversible.

Even if this print was burned, it still emitted red light when exposed to ultraviolet light.

Claims (1)

[Claims] 1 A pattern made of a transparent ink in which a colorless transparent or white inorganic fluorophore having a refractive index equal to or similar to that of the vehicle resin is dispersed is formed on a colored pattern made of colored ink, at least a part of which is formed on a colored pattern made of colored ink. A printed matter characterized in that it is printed on a support in a superimposed manner.