JPH07279098A - Safety preventive paper and apparatus for detection of forgery - Google Patents

Abstract

PURPOSE:To provide a safety preventive paper free from being readily forged and a readout apparatus therefor. CONSTITUTION:This safety preventive paper has a characteristic constitution in which safety stripes made of a shape memory alloy are buried therein. The data readout apparatus has a constitution involving a heater producing a shape memory effect and a sensor for directly or indirectly detecting the deformed amount caused thereby.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security paper for products such as securities that require anti-counterfeiting, and an authenticity judging device for the same.

[0002]

2. Description of the Related Art Conventionally, as a measure for preventing forgery of securities and the like, a method using a special printing technique such as hologram printing, which is generally difficult to forge, a method of applying a pattern with magnetic ink, an ink that can be detected only by ultraviolet rays or infrared rays It is well known to use a printing method or a method of embedding resin or metal pieces in paper as a safety wire. In order to determine the authenticity of securities and the like having a safety line, a method of irradiating an infrared light source to detect the amount of reflection and a method of detecting reflection, absorption, or magnetic change due to electromagnetic waves are known. There is also a method of recording safety assurance data by using a foil, thread, or thin film of a ferromagnetic material such as an amorphous alloy for the safety wire or utilizing the magnetic characteristics of the material (Japanese Patent Application No. 196688 (filed on July 15, 1993) "Safety protection paper and its authenticity determination device").

[0003]

With recent advances in automation and labor saving, security assurance of securities and the like has become an important issue. For example, in the case of a safety protection paper using a safety wire, the method of embedding a simple resin or metal piece in the paper has a drawback that it is easily forged by using an equivalent material. Those that use magnetic storage such as telephone cards are apt to change due to the thermal external environment and may be rewritten artificially, which is a safety issue. Although the method using a ferromagnetic material such as an amorphous alloy has solved many problems up to now, it has a drawback that it becomes expensive because a precision detection device is required to have high precision. Further, until now, a method equivalent to or superior to this method has been desired. To date, shape memory alloys have been easily used for connection parts, temperature control parts, medical equipment, daily life items, and the like. Recently, it has become possible to manufacture thin film shape memory alloys, and their utility value is increasing.

The present invention makes it possible to store data in a shape memory alloy in the form of a foil, a thread or a film, and uses it as a safety protection paper for safety assurance, so that the safety protection paper achieves both simplicity and safety assurance. And a device for determining the authenticity thereof.

[0005]

In order to solve this problem, the safety protection paper according to the present invention comprises (Ti) x (Ni) y.
A shape memory alloy alone, or a shape memory alloy, or a composite material in which a ferromagnetic material in the form of foil, thread, film, or powder is laminated is embedded in a safety wire. As a means for reading the data stored in the safety wire, a heater for heating the safety wire, a sensor for detecting a deformed portion of the safety wire deformed by the heating, or a magnetic sensor for detecting a magnetic change due to the deformation. It is composed of a pressurizing device for returning the deformed safety wire to its original shape again, and a safety protection paper authenticity determination device having a determination circuit for processing the detected data and determining the authenticity.

[0006]

Function: Ti-Ni alloy (Nitinol) or F
Several kinds of alloys added with e, Cu, Pd, etc. have a property called shape memory effect. This is the property of the plastically deformed alloy returning to the shape before deformation when the temperature exceeds a certain transformation temperature, and is considered to be a phenomenon that accompanies the martensitic transformation. That is, in the case of ordinary metal, when the change exceeds the elastic limit, elastic deformation occurs after the deformation stress is removed, and the metal generally does not return to its original shape.
However, in the case of a Ti-Ni alloy, when the alloy is stressed and deformed during cooling from a melted or quenched state, slip deformation occurs between atomic crystals in a normal metal, which is called a so-called martensitic transformation. Causes deformation that is tightly coupled. This kind of alloy remembers this state as internal energy, and has the property of returning to the initial deformed state when heat energy is applied from the outside even if it is deformed beyond the elastic limit in the cooled state. In general, deformation exceeding the elastic limit is not recovered by heat in metal, but shape memory alloys such as those mentioned above are used in many fields such as pipe joints, air conditioning control, eyeglass frames, etc. There is. On the other hand, as a means of guaranteeing security for securities, etc., by embedding a safety line in which safety data is stored in paper and reading the data and detecting the special material of the safety line, higher safety is achieved. However, it is possible to make a safety line for this purpose from a shape memory alloy and use the shape-memorized shape as the data storage means.

For example, a line bent in a direction traversing a strip-shaped shape memory alloy is plastically memorized at a certain interval. The strip is inserted into the paper as a safety strip that is flattened by causing a martensite transformation by rapidly cooling from the critical temperature while applying a pressure that deforms above the elastic limit. When the critical temperature that causes re-deformation is given to the paper containing the safety line at the time of reading, the fold curve stored on the shape memory alloy is reproduced. If the unevenness of the line is detected by, for example, a pressure sensor, it can be detected as meaningful data from the line interval. In addition, the strip-shaped shape memory alloy is memorized for the mountain-like deformations, arranged at a certain interval, the strips are flattened, and appropriate holes are made in the parts where the peaks are present, and the same diameter is also applied to the non-mountain parts. Make a hole. In this state, it is not possible to distinguish between a hole with a peak and a hole without a peak, but when the critical temperature that causes re-deformation is given, the hole in the peak has a small diameter due to the pressure from the surrounding deformation. Become. Since the diameters of the non-mountain portions are the same, it is possible to detect the distinction between the light source from the outside and the light amount detection sensor. It is possible to obtain meaningful data by combining the diameters. A composite material in which a shape memory alloy is used as a substrate and a ferromagnetic material is laminated or coated thereon can also be used for data storage.

As described above, after the folded lines are deformed and memorized at certain intervals in the shape memory alloy coated with the magnetic material,
Extend it flat and insert it into the paper as a safety line.
In order to magnetically read information from this safety wire, the magnetic material is magnetized vertically or horizontally by an external magnetic head, and heated above the critical temperature at which the shape memory alloy is deformed. At the same time that the shape memory alloy undergoes fold deformation, the applied magnetic material also undergoes the same deformation. Since the magnetic material is uniformly magnetized when flat, the direction of the lines of magnetic force and the distance from the detection magnetic head change when deformation occurs. Read the change with a magnetic head. Since the changed portion is the distance between the filaments stored in the shape memory alloy in advance, meaningful data can be obtained by combining the distances.

Shape memory characteristics are such that when stress is applied to a shape memory alloy and strain is applied, the temperature at which the original shape begins to change is As, and the end temperature is As, where As and Af temperature are set to certain values. It is possible. By using a shape memory alloy with specified As and Af temperatures, when detecting, it is determined whether or not there is heating or deformation with a heater that controls the unique temperature of the alloy and whether it is a predetermined material to be used. You can check. When it is used as a safety line, it is possible to provide a safer safety protection paper.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention, in which 1 is a security paper such as security-lined securities. 2 is a safety wire, which is made of a shape memory alloy or a composite material with a magnetic material.

FIG. 2 shows a state in which information is stored in the shape memory alloy 3. (A) shows that the data storage is realized by the presence or absence of the folded state 3a in the direction traversing the shape memory alloy 3. The folding state can be detected by a pressure sensor or the like. Normally, it is a flat plate-shaped material that is given a stress that causes deformation beyond the elastic limit, and it is not possible to determine how the data fits. (B) is a case where the size of the hole is used as a data memory, and the shape memory alloy 3 is provided with a hole 3b1 that deforms large or small as the shape memory. This hole 3
Separately from b1, a hole 3b2 having the same diameter as the hole diameter when the shape memory is not restored is formed at regular intervals. As described above, normally, external pressure is applied so that the holes have the same diameter. When heated, a combination of different hole diameters can be made due to the shape memory effect. This can be detected by an optical sensor. Further, even when it is inserted in the paper, it can be detected by selecting an optical sensor having a wavelength transparent to the paper. (C)
Is a shape memory alloy 3 to which a magnetic layer 4 is applied or adhered, and the shape of the magnetic material also changes to the same shape as the shape changes. If a uniform magnetic pattern is magnetically stored in the magnetic layer 4 in advance, when it is deformed, the uniformity of the magnetic pattern changes at the deformed portion. This is a magnetic head,
It can be detected by a magnetic sensor such as a Hall element.

FIG. 3 shows a shape memory alloy 3 as shown in FIG.
2 is an example of an authenticity determination device that uses a safety protection paper 1 that uses as a safety line 2 as a detection target. The heater 5 is heated by the heating power source 8 so as to reach the critical temperature of the shape memory alloy 3 or higher. By this heating, the shape memorized on the shape memory alloy 3 is recovered and reproduced. This change amount is measured by the pressure sensor 6
To detect. To extract this deformation amount as meaningful data, prepare two types of intervals for the deformed parts,
If you assign "0" to one side and "1" to the other side, "0"
It is possible to make meaningful information by combining “1”. The deformed shape memory alloy is cooled by the cooler 14 and returned to the flat original shape by the re-rolling roller 7. The cooler 14 may be provided in front of the pressure sensor 6, or the re-rolling roller 14 may be made of a material having good thermal conductivity so as to have a cooling function.

FIG. 4 is an explanatory diagram of an information recording method when used as a composite element of a shape memory alloy and a magnetic material.
(A) shows a state in which the magnetic layer 4 is applied on the shape memory alloy 3 and magnetized in the horizontal direction. (B) is an example of a waveform read by a magnetic sensor such as a magnetic head. If it is magnetized uniformly, the read voltage is constant. (C)
Indicates a state of being deformed by causing a shape memory effect by heat. (D) is a waveform example read by the same method as (b). If the deformation is above the magnetic head, the distance to the head becomes closer and the read voltage becomes higher. Such a voltage change varies depending on the shape and amount of deformation, and can be performed by various magnetic recording methods such as perpendicular magnetic recording performed in advance.

FIG. 5 shows an example of the authenticity determination device for the safety protection paper 1 using a composite material with a magnetic material. Reference numeral 1 is a protective paper in which a safety wire 2 made of a shape memory alloy coated with a magnetic material is embedded. The excitation head 9 is for uniformly magnetizing the safety wire 2. The uniformly magnetized safety wire 2 is heated to a critical temperature which causes a shape memory effect by a heater 5 whose temperature is controlled by a heating power source 8. For heating, a laser beam, a microwave, or the like may be used instead of the heater. Reference numeral 11 is a detection magnetic head for reading change information according to the principle described with reference to FIG. Reference numeral 12 is a degaussing head for degaussing for confidentiality. A re-rolling roller 7 is for re-flattening the deformed shape memory alloy. A signal amplification amplifier 13 amplifies the signal from the detection magnetic head 11 and is connected to the signal processing unit. Reference numeral 14 denotes a cooler, which has the same function as that used in FIG.

FIG. 6 shows the state of signal processing performed in the signal processing section. (C) is a shape memory alloy 3 with a magnetic layer 4 in which strains are stored in advance so as to have deformed portions with different intervals, and is deformed by heat.
Different voltages are detected at certain intervals as shown in FIG. This signal is compared with an appropriate voltage Vs as a reference to obtain V
If s or more is “with signal” and Vs or less is “without signal”, a binarized signal as shown in (b) is obtained. When the safety wire is sent at a constant speed, the signal interval becomes a time interval. Therefore, by making the difference in the time interval correspond to "1" and "0", meaningful data can be obtained by this combination.

[0016]

As described in detail above, the safety protection paper according to the present invention using the safety wire made of a shape memory alloy or a composite material with a magnetic material capable of storing data on paper such as securities is simple. It has a simple structure and can be manufactured at low cost, and the data detection method is simple. Data cannot be read out under normal use conditions, and those made of such materials can control temperature and amount of deformation by material components, and are generally difficult to forge, have confidentiality, and have high safety. it can. In addition, the authenticity determination device according to the present invention, which uses such a safety protection paper as a detection target, can be stabilized with a simple configuration to obtain a reliable determination result.

[Brief description of drawings]

FIG. 1 is a perspective view of a safety protection paper according to the present invention having a safety line.

FIG. 2 is a safety wire in which data used in the present invention is stored, (a) using folds, (b) using hole diameters, and (c) applying magnetic material. Is.

FIG. 3 is a configuration example of an authenticity determination device according to the present invention using a pressure sensor.

FIG. 4 is a time chart for explaining a state in which safety line data coated with a magnetic material is read by the apparatus of FIG.

FIG. 5 is a configuration example diagram of an authenticity determination device according to the present invention using a magnetic sensor.

6 is a time chart for explaining a state in which signal processing is performed by the device of FIG.

[Explanation of symbols]

 1 Safety Protective Paper 2 Safety Wire 3 Shape Memory Alloy 4 Magnetic Layer 5 Heating Heater 6 Pressure Sensor 7 Re-rolling Roller 8 Heating Power Supply 9 Excitation Head 10 Excitation Power Supply 11 Detection Magnetic Head 12 Degaussing Head 13 Signal Amplification Amplifier 14 Cooling Machine

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ichiro Mizukami 1-741 Kugayama, Suginami-ku, Tokyo Iwasaki Communications Machinery Co., Ltd. Communication machine Co., Ltd.

Claims (2)

[Claims] 1. A shape memory alloy or a ferromagnetic material laminated on the shape memory alloy, wherein a film, a foil, or a thread-shaped safety wire in which safety assurance data is fixedly stored is embedded in a sheet. Security paper to do. 2. The safety wire is heated or cooled to a shape transformation temperature in order to detect the shape memorized safety assurance data from the safety wire, with the safety wire being handled. Data detecting means for detecting displacement or magnetism of shape change of the strip, and the safety assurance data read by the data detecting means are properly matched with predetermined intrinsic safety assurance data, and the shape transformation is performed. When the temperature characteristics properly match the temperature characteristics of the safety wire, it is determined that the safety protection paper is genuine, and the read safety assurance data is proper with the predetermined safety assurance data. Or the detected shape transformation temperature characteristic does not properly match the temperature characteristic of the safety wire, the determining means determines that the safety protection paper is counterfeit, and the change of the safety wire. An authenticity determination device for a safety protection paper, comprising means for pressurizing the safety protection paper in a state of being lowered to the shape transformation temperature or lower in order to restore the shape portion.