JPS633758B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for preventing counterfeiting of seals using thermal ink.

Conventionally, for documents such as securities, various certificates, contracts, etc. that are executed or executed by stamping a seal,
In order to protect the stamp area and prevent tampering, a transparent film label is pasted on it.

Especially for things like gift certificates and certificates of deposit, it is important to prevent counterfeiting of seals, as even a person who is not the original party can use them by obtaining a seal that gives the same impression as the stamp on which they were affixed. However, with the above-mentioned general seal field protection method, the seal impression is obvious to anyone, so it is possible to produce identical seals, and it is also possible to tamper with the seal impression by peeling off the transparent film label. It's not that difficult since you can see the seal.

To compensate for this, an anti-counterfeiting method using black tape and infrared light was devised. This involves pasting a black tape over the stamped seal, making it invisible unless infrared rays are irradiated. Compared to the conventional method of just pasting a transparent film label, at least the imprint is not directly visible, which makes counterfeiting more difficult.
Anyone with the equipment can irradiate infrared rays and view seal impressions, and the equipment is easy to use. Also, the fact that someone else saw the seal cannot be known from the face of the ticket. Therefore, this method is still insufficiently effective in preventing counterfeiting.

The present invention was made with the intention of solving the above-mentioned problem, and the seal imprint cannot be easily seen, and once the seal imprint is seen, it is visible on the seal area, so that the seal is not easily visible. The purpose of the present invention is to provide a method for preventing the forgery of a seal by making it clear that the impression of the seal has been stolen prior to its legitimate use and warning of the danger of forgery.

Here, as can be seen from the above explanation, the term "inkan" has a meaning that includes not only a seal as a tool but also an impression of a seal stamped on the face of a banknote. Therefore, the present invention provides a method for preventing counterfeiting of the stamp itself and at the same time preventing falsification of the stamp impression.

The method for preventing counterfeiting of seal stamps of the present invention utilizes a two-component reaction type thermal ink,
Printing is performed with an ink containing one of the components of a two-component reaction type heat-sensitive coloring agent consisting of two components, material A and material B, for example, material A and a fluorescent material, and then a heat-sensitive coloring agent is applied over the ink instead of vermilion. The remaining components of the agent, such as material B, are used to stamp a stamp, and the stamped surface is covered with a film containing an ultraviolet absorber.

To explain with reference to the drawings, first, material A of a two-component reaction type thermosensitive coloring agent and a fluorescent material are applied to the part to be stamped on securities 1 made of paper, synthetic paper, plastic film, or any other material. Printing 2 is prepared on one surface or in a desired pattern using an ink containing the following in an appropriate vehicle.

When creating a document, a seal is stamped on the above-mentioned print 2 using an ink containing material B, a two-component reaction type heat-sensitive coloring agent, mixed in an appropriate vehicle, instead of ink, and stamp impression 3. Create.

In this state, if you irradiate black light, that is, light that cuts off the visible light region and mainly consists of ultraviolet light,
The base ink 2 contains a fluorescent material, and the ink 3, which replaces the ink, does not, so there is a difference in the brightness of the reflected light between the stamp area and its surroundings, making it easy to see the stamp. . If the colors of ink 2 and ink 3 are the same, or at least if ink 2 is a darker color, it will be impossible to read the seal impression with the naked eye under visible light.

Subsequently, a transparent film cover 4 containing an ultraviolet absorber is pasted onto the stamped surface using an appropriate adhesive 5 or the like. The adhesive may be applied to the entire surface of the cover. After applying this cover,
Even when irradiated with black light, the ultraviolet light is absorbed and no fluorescence occurs in the ink 2 area, so ink 3
There is no difference in the brightness between the area and the reflected light, making it impossible to read the seal impression at all.

To verify the impression of a seal when exercising securities, etc., it is sufficient to apply heat to the part where the seal is affixed. The desired color appears in the part of the stamp where the A and B materials of the two-component reaction type thermosensitive color forming agent are in contact, and the stamp is visible.

There are several known two-component reaction type heat-sensitive color formers, including a combination of a phenol compound and a leuco dye, and any of them may be used. However, in order to be able to record the fact that the impression has been seen even once, it is necessary to choose one that undergoes an irreversible coloring reaction upon heating.

In carrying out the present invention, as can be seen from the above description, care must be taken to wipe off the vermilion of the seal before use. If it is bothersome or cannot be wiped off completely, it is recommended to wear vermilion camouflage. That is,
The solution is to add a dye of the color of vermilion or a color similar to it to the ink containing material A, or to color the film cover so that it cannot be identified even if vermilion is attached.

Known techniques can also be incorporated into the present invention, such as cutting a slit around the film cover to make it difficult to peel off. In addition, the present invention may have various other aspects.

[Brief explanation of the drawing]

The drawings are views showing the seal area of securities to which the method of the present invention is applied, and FIG. 1 is a plan view;
FIG. 2 is a sectional view. 1... Securities, 2... Ink containing material A of a two-part reaction type heat-sensitive coloring agent and a fluorescent material, 3... Imprint of ink containing material B of a two-part reaction type heat-sensitive coloring agent, 4...
Transparent film cover containing ultraviolet absorber, 5...Adhesive.

Claims (1)

[Scope of Claims] 1. Printing is performed with an ink containing A material and a fluorescent material of a two-component reaction type thermosensitive coloring agent consisting of two components A material and B material, and then B material is added instead of vermilion. A method for preventing counterfeiting of a seal using heat-sensitive ink, which comprises stamping a seal using an ink containing the same, and covering the stamped surface with a transparent film containing an ultraviolet absorber. 2. The method according to claim 1, in which bisphenol A is used as the A material and leuco dye is used as the B material of the two-component reaction type thermosensitive coloring agent. 3. The method according to claim 1, in which the ink and/or transparent film containing material A are colored in vermilion or a color similar to vermilion.