JPH02293500A - Paper for judging forgery - Google Patents

Abstract

PURPOSE:To obtain the title paper capable of exhibiting fluorescence reaction by exposing ultraviolet ray, etc., by blending a fiber, e.g. natural fiber such as pulp, chemical fiber such as rayon or synthetic fiber such as PE, which was dyed using a fluorescent whitening agent, as part of paper material and making the blend into paper. CONSTITUTION:The aimed paper obtained by blending a fiber, e.g. natural fiber such as pulp, flax or linter, chemical fiber such as rayon or synthetic fiber such as PE or polyester, which was dyed using a fluorescent whitening agent, as part of paper material and making the blend into paper.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is applicable to various stock papers, gift certificates, important documents, etc., which may cause great damage if forged.
This relates to counterfeit identification paper used for containers, etc., which may be damaged by counterfeit packaging. ? Conventional technology) Traditionally, specially made paper containing colored fibers, printed paper chips, and other separable substances has been used to prevent counterfeiting and to prevent transparent characters. Patterned paper has been widely used as anti-counterfeiting paper. In particular, the method of adding watermark characters and patterns to paper is
By pressing a patterned dandy Ω-le, the fibers that make up the stock can be thickened or thinned. A method of applying letters and patterns to the paper surface between a mark roll and an elastic roll is widely known and has been used as a counterfeit prevention paper. (The problem that the invention aims to solve! #I) As stated above. Colored fibers and printed paper strips are used in the papermaking process to prevent counterfeiting. Products that contain distinguishable substances may not satisfy the consumer's needs depending on their use, and may be used as transparent characters during the papermaking process. The method of adding the pattern is that placing the character pattern at a fixed position on the final product of various dimensions is economically and technically difficult because there is no cutter that optically detects the watermark pattern with a sensor and cuts it in register. It has the disadvantage of being difficult. As a means to solve the problem of arranging watermark characters and patterns at a certain level. Recently, a method of printing a watermark pattern using a chemical solution has been developed and used. Many different methods of printing a watermark pattern have been proposed for patents, utility models, etc., but they can be easily forged by printing etc. Due to these drawbacks, there has been a demand for new counterfeit identification forms that can only be identified by consumers. The present invention may use either a special paper that is easily identified, such as conventional anti-counterfeit paper, or a commonly used paper that has not been specially treated. It's not like a black light, but it's like a black light.
We provide counterfeit identification paper that is made by dispersing fibers that exhibit a fluorescent reaction that can be identified only by the consumer by applying light of a specific wavelength from an easily fluorescent detector No. 2, or pieces of paper with hidden letters and patterns dispersed throughout the paper. The purpose is to: (Means for solving the problems) The present invention is as follows. As a result of various studies to achieve this objective, we developed a fluorescent whitening agent that emits visible blue-violet light when irradiated with ultraviolet light with a peak wavelength of 365 nm, and developed a fluorescent reaction that cannot be identified under normal conditions. This goal was achieved by dispersing fibers with a 3D pattern, or pieces of paper with hidden letters and patterns printed on them, into the paper.
In other words. The present invention uses a water-soluble optical brightener such as diaminostilbene when the material to be added to paper is fiber, and uses a synthetic resin that is soluble in organic solvents when it is a hidden printed paper piece. Fluorescent brighteners such as coumarin, oxazole, and bilazoline are used by dissolving them in transparent ink. To add fibers dyed with fluorescent brighteners to paper stock, the blending ratio can be increased or decreased as appropriate depending on the intended use, but if a large amount is added, a fluorescent reaction will be seen from the entire surface of the paper and the blending will be difficult. It is desirable that the amount is 1% or less, as this would deviate from the purpose of the present invention, which is to emit a fluorescent reaction from some of the fibers. In addition, in order to create paper in which pieces of paper are hidden and printed with transparent ink containing fluorescent brighteners and dispersed in paper stock, the transparent ink and the resin that overcoats the printed characters and patterns must be transparent. It is necessary to use a material that does not yellow and is water resistant to the extent that it does not easily decompose when disintegrated in water. For this purpose, any ink or varnish made of water-resistant resin can be used, but the simplest one is overprint varnish, hereinafter abbreviated as OP varnish. It is convenient to use. OP varnishes can be of the oxidative polymerization drying type for offset flat format printing, the ultraviolet curing type, or the solvent water-based heat curing type for gravure printing.
Varnish is generally prone to yellowing due to its constituent resins and oils, and for gravure printing that uses rolls for printing plates, OP is applied in a pattern only on transparent ink, where printing is hardly perceptible in appearance.
Since it is not easy to coat with varnish, for the purposes of the present invention, it is most desirable to use an ultraviolet curing type OP varnish that is suitable for gravure lithographic printing and does not cause yellowing. That is, it is printed using a transparent ink mixed with a fluorescent whitening agent in UV-curable OP printing plates for offset lithography. Paper cured by irradiation with ultraviolet rays uses water-resistant epoxy resin as the base resin for the ink or varnish, so if the printing interval is not continuous, if the paper is disintegrated in water, it will print one letter. Paper made by adding an appropriate amount of this as part of the paper stock has fluorescent characters that emerge when irradiated with ultraviolet light. In addition, there are disadvantages such as meaning incomprehensibility if the characters are scattered individually, so if you want to group them into phrases to promote company names, product names, etc., or if you want to distribute marks, designs, etc. throughout the paper, fluorescent whitening is recommended. Letters and patterns are formed using transparent ink containing an agent, and then an OP varnish without the fluorescent whitening agent is applied, cured, disintegrated in water, mixed appropriately with paper stock, and paper is made.
You can obtain paper on which pieces of paper such as consecutive letters, marks, and designs are distributed for each phrase. Also, printed characters dispersed in paper stock. If a piece of paper with a fluorescent pattern is printed on one side, and the non-printed side of the hidden printed paper piece is turned into paper, if the paper piece is made of cardboard, the printed characters will not be visible even when exposed to ultraviolet light. , patterns, designs, etc. cannot be seen at all, and if the paper is thin, it may be seen unclearly, but there is a problem that the text pattern may appear reversed, so if necessary, the same treatment should be applied to the back side of the paper strip to be printed hidden. By applying. This makes it possible to obtain paper that can clearly detect printed character patterns, etc., even if the paper strips are inserted facing either the front or the back. (Function) As mentioned above, paper made by dispersing fibers dyed with a fluorescent brightener and pieces of paper printed with an ink containing a fluorescent brightener in transparent ink differs from ordinary paper in appearance. However, when irradiated with ultraviolet light with a wavelength of 300 to 400 nm, it emits fluorescence in the visible range of 400 to 500 nm, making it possible to identify forgeries. (Example) The present invention will be explained according to an example. In addition, % in the examples
and parts indicate weight % and parts by weight. Example I The NBKPIOO section is dyed with 0.5 parts of a diaminostilbene optical brightener. Fluorescently dyed pulp was added to the paper stock in an amount of 0.1 part by weight, and the paper was prepared in a conventional manner. 70g// of paper was obtained. This peaked at a wavelength of 365 nm. When irradiated with a black light that emits ultraviolet light, a counterfeit identification paper was obtained in which pulp fibers that exhibit a fluorescent reaction were dispersed throughout the paper. Example 2 100 parts of rayon mixed with equal f of 1.5 denier fibers of 3, 5, and 7 mm lengths was dyed with an aqueous solution of 1 part of diaminostilbene optical brightener, 2 parts of blue dye, and 1 part of soda ash. Dye red using the same recipe by replacing the blue dye above with red dye. Pulp dyed with each color and an optical brightener is blended with 0.05% of each paper stock and made into paper using a conventional method.The resulting paper has long and short blue and red fibers dispersed in it. It is a counterfeit identification paper whose dyed fibers emit fluorescence when exposed to black light. Example 3 Using an offset lithographic printing machine equipped with an ultraviolet curing lamp, UV light having the composition shown in Table 1 was applied to 40 g 7 m' of white high-quality paper.
``Shin-Fuji'' is offset-printed using curable transparent ink, and the printed letters are separated into sections and covered with OP varnish, which excludes the oxazole optical brightener from the formulation in Table 1. Print on the back side of the printing paper so that it overlaps exactly with the characters printed on the front side. When this paper is disintegrated with a bulper, the part where "Shinfuji" is hidden and printed remains as a piece of paper for each phrase using water-resistant UV ink and varnish. Paper was made with a weight of 120 g/male. This paper is irradiated with ultraviolet light with a peak wavelength of 365 nm.
When exposed to a black light, the hidden printed characters emerged and a counterfeit identification paper was obtained.
8 Trimethoxy o-% propane tri7 acrylate 3 02- and 1 Roxy 2-methylpropyl phenone 62. 2-Dimethoxy 2-phenyl 77 tophenone 4
Wax 1 Jetano-47mi/
1 Adding 0.5 parts of an oxazole fluorescent brightener to 100 parts of the above resin (effects of the invention) The present invention has been developed for the first time by irradiating ultraviolet rays on paper, which is completely indistinguishable from ordinary paper in appearance. Bath fibers dyed with fluorescent whitening agent and pre-printed letters at 61 degrees. In the case of Example 2, which has a thick pattern, Jalta is combined with a colored dye and a fluorescent whitening agent to achieve the design of fancy paper, which is usually called paper with threads, and the anti-counterfeiting function of fluorescent coloring. At the same time, it is possible to obtain satisfactory paper and to provide P4 anti-forming paper with unprecedented functions. Patent applicant Shin-Fuji Paper Co., Ltd.

Claims (2)

[Claims] (1) Making paper by mixing pulp dyed with optical brighteners, natural fibers such as hemp and linter, chemical fibers such as rayon, synthetic fibers such as polyethylene and polyester, etc. as part of paper stock. A counterfeit identification paper featuring: (2) Detection of counterfeiting, which is characterized by the fact that it is made by dispersing thin paper into paper stock, on which letters, patterns, etc. are printed by adding a fluorescent whitening agent to transparent ink made of natural resin, synthetic resin, oil, etc. Paper.