JPH06111055A - How to read code pattern information - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a method capable of reading code pattern information that is substantially invisible, without limiting the color of printed matter. A method for reading code pattern information, which comprises irradiating an infrared absorption code pattern with infrared rays and detecting infrared absorption by the infrared absorption code pattern, comprising:
A method for reading code pattern information, wherein the print layer near the infrared absorption code pattern is formed of a process ink using format black as black ink.
The infrared absorption code pattern has absorption above 800 nm, while process ink absorption is below 800 nm. Furthermore, an article having an infrared absorption code pattern and a printed layer on a substrate, wherein the printed layer is formed of a process ink using format black as the black ink.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for reading code pattern information. More specifically, the present invention relates to a method of reading code pattern information that is substantially invisible. The invention further relates to articles having a code pattern that is substantially invisible.

[0002]

2. Description of the Related Art Printed matter such as a label and a card provided with a code pattern such as a bar code which can be detected by optical means has been widely used. A general bar code is composed of a black bar (printed part) and a white bar (non-printed part), and the recorded information can be read by detecting the width of each black and white bar by an optical means.

However, such a bar code can be visually recognized. Therefore, the code pattern may be unfairly read for the purpose of fraud, forged or altered, and there is a problem that the safety is insufficient. Further, there is a problem that the information cannot be read because the barcode is intentionally damaged. Further, the visible code pattern may impair the aesthetic appearance of the article to which the code pattern is attached, or may cause inconvenience due to a reduction in printing space other than the code pattern.

On the other hand, JP-A-63-307996
The publication discloses a code pattern using an ink containing a Millory Blue pigment that absorbs infrared rays. This code pattern is covered with a printing layer by printing an ink which transmits infrared rays and has a hiding property on the code pattern, and further prints a pattern with a general printing ink on the ink. However, the ink containing the Millory blue pigment absorbs visible light and exhibits a blue color. Therefore, hiding by the print layer is not easy, and it is impossible to detect the code pattern itself depending on the print layer.

Separately from this, Japanese Patent Application Laid-Open No. 3-275389 discloses a printed matter with an identification mark having a print area printed with a dropout color ink which transmits infrared rays and an identification mark provided in the area. Disclose. This identification mark is invisible because it contains glass powder that transmits visible light and absorbs infrared light, and can be detected by infrared light. As the glass powder, specifically, iron-containing glass powder and copper-containing glass powder are described.

However, in this method, the dropout color ink is used as the printing ink, and there is a drawback that the colors that can be adopted are extremely limited.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method capable of reading substantially invisible code pattern information without limiting the color of printed matter.

[0008]

SUMMARY OF THE INVENTION The present invention is a method of reading code pattern information for irradiating an infrared absorption code pattern with infrared rays to detect infrared absorption by the infrared absorption code pattern, the method comprising: The printed layer of 1. is formed of a process ink using format black as the black ink.

The present invention will be described below. The infrared absorption code pattern has absorption in the infrared region of 800 nm or more and does not substantially absorb light rays including visible light of less than 800 nm. There are no particular restrictions on the material, forming method, shape or the like of the infrared absorption code pattern. Examples of the infrared absorber include organic dyes such as cyanine dyes, phthalocyanine dyes, naphthoquinone dyes, anthraquinone dyes, dithiol dyes, and triphenylmethane dyes. Further, glass containing copper ions (Cu ²⁺ ) (having a broad absorption peaking at 800 nm) and glass containing ytterbium (Yb ³⁺ ) ions (having a sharp absorption at 830 nm) are used as infrared absorbers. You can also The infrared absorption code pattern can be formed using an ink containing these infrared absorption agents and a vehicle or the like. The shape of the code pattern may be a character, a symbol, etc., in addition to the one-dimensional barcode and the two-dimensional barcode.

On the other hand, the print layer is formed by using a process ink that uses format black as the black ink. The process ink is composed of four colors of yellow ink, magenta ink, cyan ink and black ink, and is an ink capable of reproducing all colors by printing four colors. In general process ink, carbon black is used as a complexion color for black ink. But,
In the present invention, format black, which is a mixed color ink of yellow, magenta, and cyan, is used as the black ink.

FIG. 1 shows the absorption spectra of the four color inks forming the printing layer and the absorption spectrum of the code pattern. First, yellow ink, magenta ink, and cyan ink do not absorb in the infrared region of 800 nm or more. Carbon black has a strong absorption even in an infrared region of 800 nm or more, whereas format black has substantially no absorption in a wavelength of 800 nm or more. Therefore, the print layer formed using the process ink using format black as the black ink does not interfere with the infrared absorption of the code pattern.

In the method of the present invention, code pattern information is read by irradiating the printed layer and the code pattern with infrared rays and detecting infrared absorption by the code pattern. The infrared irradiation can be performed using, for example, a semiconductor laser. The infrared absorption can be detected using, for example, a phototransistor.

Further, the present invention is an article having an infrared absorption code pattern and a printed layer on a substrate, wherein the printed layer is formed by a process ink using format black as black ink. Regarding the above articles.

The infrared absorbing code pattern and the printing layer are
These are described as the infrared absorption code pattern and the printed layer, respectively. The material of the substrate may be any material that does not substantially absorb infrared rays from the viewpoint of not obstructing the reading of information of the infrared absorption code pattern. For example, paper, plastic, non-woven fabric, metal, ceramics and the like can be exemplified. The article is not particularly limited,
Examples include pamphlets, labels, cards, containers, molded products and the like.

In the article of the present invention, an infrared absorption code pattern is formed on a substrate and a print layer is further formed thereon (article shown in FIG. 2), or a print layer is formed on the substrate, Further, it can be manufactured by forming an infrared absorption code pattern on it (article shown in FIG. 3). The infrared absorbing code pattern can be formed by using a thermal transfer ribbon printer, an electrophotographic printer, an inkjet printer, or the like using the ink containing the infrared absorbing agent. Further, the process print layer can be formed by a conventional method using process ink.

The present invention will be described below with reference to the drawings. FIG. 2 shows a mode in which the code pattern 20 is provided on the substrate 30 and the print layer 10 is provided thereon. In this case, the light source 40
Infrared rays are emitted from the infrared ray absorbing code pattern 20 through the printing layer 10. Since the printed layer 10 does not absorb the radiated infrared rays, the light rays 50 not hitting the code pattern are reflected by the substrate 30, and the reflected light 51 reaches the light receiving device 60. On the other hand, the light rays 52 that strike the code pattern 20 are transmitted through the printing layer 10, but the irradiation infrared rays are absorbed by the code pattern 20. As a result, the pattern of the code pattern 20 can be read from the bright and dark patterns of the irradiation infrared rays of the reflecting portion and the absorbing portion.

In FIG. 3, the printed layer 10 is provided on the substrate 30,
A mode in which the code pattern 20 is provided thereon is shown. In this case, the light ray 53 not hitting the code pattern 20 is transmitted through the printing layer 10, is reflected by the substrate 30, and is reflected by the reflected light 54.
Passes through the printed layer 10 again and reaches the light receiving device 60.
On the other hand, in the light rays 55 that hit the code pattern 20, the irradiation infrared rays are absorbed in the code pattern 20, and the substrate 3
Since the reflection at 0 does not occur, the light receiving device 60 is not reached. As a result, it is possible to read the pattern of the code pattern 20 from the infrared light and dark patterns of the reflection portion and the absorption portion.

As the light source 40, it is possible to use an infrared light source such as an infrared LED (light emitting diode) or an infrared laser which has been conventionally known as it is. Although the light source 40 and the light receiving device 60 are shown separately in FIGS. 2 and 3,
A scanner in which both are integrated may be used.

[0019]

According to the method of the present invention, code pattern information that is substantially invisible can be read from a printed matter of any color.

[Brief description of drawings]

FIG. 1 shows absorption spectra of yellow ink, magenta dye, cyan ink, format black ink, and infrared spectrum of an infrared absorption code pattern.

FIG. 2 is an explanatory view of the method of the present invention.

FIG. 3 is an explanatory view of the method of the present invention.

[Explanation of symbols]

 10: Printed layer 20: Infrared absorption code pattern 30: Substrate 40: Light source 50-55: Light ray 60: Light receiving device

Claims (3)

[Claims] 1. A method of reading code pattern information, which comprises irradiating an infrared absorption code pattern with infrared rays to detect infrared absorption by the infrared absorption code pattern, wherein a printing layer near the infrared absorption code pattern is formatted as black ink. The above method, wherein the method is formed by a process ink using black. 2. The infrared absorption code pattern is 800 n
The method according to claim 1, comprising a ytterbium ion-containing glass having an absorption at m or higher. 3. An article having an infrared absorption code pattern and a printed layer on a substrate, wherein the printed layer is formed of a process ink using format black as black ink.