JP2010150680A - Method for producing thread - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an efficient method for producing threads suitably useful for uses of anti-counterfeit paper. <P>SOLUTION: Threads suitably useful for uses of anti-counterfeit paper are produced by forming metal this film layers 3 and 4 on both front and rear surfaces of a web-like substrate 2 having light transmission with light-transmitting parts B left at the ends of the substrate, printing a pattern on fixed positions with a colored resin layers 7 and 8 on the front side and back side and slitting the substrate after demetallizing process. Since the light-transmitting parts B are left at the edges of the substrate, position adjustment is easily carried out in printing the back side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a thread (also referred to as a strip, a filament, a thread, a safety strip, or the like) suitable for a field where anti-counterfeiting is desired. More specifically, various threads proposed in the international application number PCT / JP2006 / 313855 (international publication number WO2007 / 007784A1) previously filed by the present applicant are, of course, other configurations included in the concept of this patent. It is related with the proposal of the suitable manufacturing method of this thread | sled.

  An anti-counterfeit paper called “threaded paper” in which a thread is formed in a paper layer is well known. Since the threaded paper requires extremely advanced technology for manufacturing, it has a great effect on prevention of tampering or counterfeiting, and is widely used for various types of cash vouchers, securities, certificates, ID cards, passports, tickets, confidential documents, etc. in use.

  There are two types of threaded paper, one of which is threaded into the paper and not exposed to the paper surface, and the other is a part of the thread on the paper surface. It is called “paper with open window thread” exposed intermittently.

  In the former method, the thread is not exposed on the surface. The method is to insert a nozzle into the stock flow in the slice part of the long paper machine, and feed the thread while flowing water through the nozzle to form the paper network. The thread is inserted into the paper web (see, for example, Patent Document 1), or a thread insertion device is installed in the paper material flowing out of the flow box of the long paper machine. Using a method of making a thread while keeping a non-contact state (for example, see Patent Document 2) or using a circular net paper machine having two or more layers, the inner wall is made uneven by combining two or more layers. A method has been proposed in which a thread is sent out between paper layers by using the pipe and a thread is drawn between paper layers (for example, see Patent Document 3).

  In addition, as a method of manufacturing the latter “paper with a window open thread”, a belt mechanism having a groove through which a thread is passed at the tip of a convex portion of a guide having an uneven portion is embedded in a paper suspension on a wire. (For example, see Patent Document 4) or using a mesh processed into an uneven shape for the upper screen of a circular paper machine, inserting the thread while contacting the uneven surface of the mesh surface, (For example, see Patent Document 5), or a compressed air nozzle is built in a rotating drum on a wire of a long web paper machine, and slurry on a thread previously inserted into a web is intermittently compressed with compressed air. A method (for example, refer to Patent Document 6) in which a thread is blown away to expose a thread has been proposed.

  The above-mentioned “paper with a window empty thread” is characterized in that a window empty part having a thin thickness is formed intermittently in the paper flow direction, and the thread is exposed in this window empty part. Therefore, in paper manufactured using a thread that has no adhesive applied to the surface, rubbing the exposed part of the thread with a nail or the like can easily cause the thread to peel off or lift the thread during printing. Disadvantages. For this reason, paper with a window thread is made using a thread with a heat-sensitive adhesive on the surface, and when the paper is dried in the drying zone of the paper machine, the heat-sensitive adhesive applied to the thread is melted or dried. By softening, measures have been taken to ensure that the cellulose fibers and threads that make up the paper are bonded together and to increase the peel strength.

  A wide variety of configurations have been proposed for the threads used for the threaded paper. For example, a hologram thread, a magnetic thread, a thread that develops fluorescence when irradiated with ultraviolet light, a thread coated with a thermochromic agent, a metal vapor deposition thread, a thread with micro characters, and the like have been put into practical use.

  Among them, the thread with micro characters is a method of stamping directly on a plastic film, a method of selective metallization using a mask or a template in a vacuum deposition apparatus, a demetallization process (a metallization and non-metalization due to corrosion "pastor processing It is known that it is manufactured by the “method” or “water-washed sealite processing method” using a water-soluble resin (see, for example, Patent Document 7).

  Threads in which micro characters are formed by the above “demetallization” are often used for foreign banknotes. For example, in current US dollar banknotes and European euro banknotes, paper with a structure in which threads are buried between paper layers is exposed intermittently on windows in German 100-mark banknotes before transitioning to euro banknotes. Composition paper is used. The micro-characters formed in these threads are arranged so that “correct characters” in the correct orientation and “inverted characters” upside down are alternately positioned in the original view.

  This means that the design is such that the thread may be reversed when paper is made. In other words, it means that there is no distinction between the front and the back of the thread. The micro character refers to a very small character in consideration of anti-counterfeiting performance, but in the present invention, unless otherwise specified, not only characters but also patterns considering aesthetic design are included. The pattern form is collectively referred to as a micro character.

  In addition, there are cases in which the character forming part is a metal deposited layer (such as the US dollar banknote) and the micro character forming part is a blank character (such as the German 100 mark banknote). In other words, there are “positive” and “negative” micro characters.

  In addition, there is a proposal of anti-counterfeit paper that has been printed on paper by distinguishing the front and back of the thread. This proposal is based on anti-counterfeit paper that has been threaded in the flow direction of the paper, and the thread is a base film. A positive character only micro-character consisting of a metal vapor-deposited layer formed on the surface of the film, a printed layer made of a transparent ink formed on the metal vapor-deposited layer, and a heat-sensitive adhesive formed on the back surface of the film The ink forming the printing layer is added with dyes and pigments that develop color when irradiated with ultraviolet rays. When viewed from the front side of the paper, the threads are formed so that positive micro characters can be seen. This is a forgery-preventing paper whose outline is that it is engraved on the paper. By configuring this thread, the printed layer of the thread is generated when the thread is irradiated with ultraviolet rays. By determining whether appear to, effect that identification of the front and rear surfaces of the thread can be easily. In this patent, the micro characters made of a metal vapor-deposited layer are obtained by so-called “demetallization” (see, for example, Patent Document 8).

  The thread proposed in Patent Document 8 is observed from the back side of the paper only when the micro-character image on the front side of the thread is observed when viewed from the front side of the paper. When this happens, the micro-characters formed on the thread are usually observed as “reverse” with the left and right or upside down. In general, a thread having such a configuration does not necessarily cause a reduction in the value of a product in the case of a gift certificate or stock certificate. However, depending on the needs of society and the market (customers), if it is required to use the front and back of the paper or printed matter in the same way, for example in the case of a passport body paper, etc. However, when viewed from the front side and the back side of the paper, it is preferable that they can be viewed in the same direction (the same normal direction from the front side or from the back side, or the same reverse direction from the front side or from the back side). , It can be a lot.

  Further, depending on the needs of society and the market (customers), there is a great possibility that it is desired to make the micro-character image of the thread visible from the front side invisible (or difficult to see) from the back side. Since this overturns the expectation that something should be seen, of course, it can be expected to be effective as a contrivance for anti-counterfeiting measures and as a contrivance for giving fun as a sense of fun.

  As an improvement to these requirements, a thread having an unprecedented structure has been proposed (Patent Document 9). Specifically, when trying to observe the micro-characters of the thread from one side and the opposite side of the paper or printed matter, the micro-character image can be visually recognized in the same direction from either side, not the opposite direction. When an image of a micro character of a thread can be visually recognized from one side of a sheet or printed matter, the image of the corresponding micro character cannot be visually recognized (or difficult to view) when observed from the opposite side, and a thread satisfying these was suggested.

The prior art documents described above are shown below.
Japanese Patent Laid-Open No. 51-130309 JP-A-2-169790 Japanese Patent Publication No. 5-40080 Japanese Patent Publication No. 5-85680 U.S. Pat. No. 4,462,866 JP-A-6-272200 Japanese Examined Patent Publication No. 6-062030 (5 column 46 line to 6 column 3 line, 7 column 26 line to 8 column 12 line) Japanese Patent No. 3279212 WO2007 / 007784A1 publication

  In Patent Document 9, a metal thin film layer is formed on both surfaces of a light-transmitting substrate, a colored resin layer is printed on the pattern, and the patterned colored resin layer is used for etching resistance. By etching the metal thin film layer as a mask, the metal thin film layer and the colored resin layer are formed so as to overlap in the same pattern, and then the base material is cut so as to have the width of the thread. The thread has been described.

  Here, for facilitating understanding, a thread manufacturing method proposed in Patent Document 9 (WO2007 / 007784A1) will be described. 1, 2, and 3 of the present invention are the same as FIGS. 1, 2, and 3 of the publication. FIG. 1 is a plan view schematically showing materials for manufacturing the thread of the invention of Patent Document 9. A plurality of rows of metal thin film layers 3 and colored resin layers 7 printed thereon are formed on a web-like substrate 2 having light transparency. FIG. 2 is an explanatory diagram of a partially enlarged side cross-section of FIG. 1, in which a metal thin film layer 3 is formed on the entire surface of a web-like and light-transmitting substrate 2, and printed thereon. A colored resin layer 7 is formed, and a colored resin layer 8 printed on the metal thin film layer 4 not shown in FIG. The printed colored resin layers 7 and 8 are printed as micro character patterns. In the description of the above invention of Patent Document 9, it is assumed that the colored resin layers 7 and 8 are formed by printing, but pattern formation is performed by a general photolithography technique including exposure and development steps. Is also possible.

Further, the metal thin film layers 3 and 4 are formed by depositing a metal by a vacuum deposition method as a good example in the above invention of Patent Document 9. In the above invention of Patent Document 9, an appropriate light shielding property and light reflectivity are obtained. It is preferable from the viewpoints of ease, workability, cost, and the like. In addition, for the film formation of the metal thin film layers 3 and 4 of the said invention of patent document 9, you may use another film-forming technique suitably as needed.

  Moreover, the colored resin layers 7 and 8 are formed by forming an ink mainly composed of a coloring material and a resin into a desired pattern using an appropriate printing technique, as a good example in the above invention of Patent Document 9. Although it is described that there is a merit that a desired pattern can be easily formed with high accuracy by appropriately selecting a printing technique, it is also possible to form a finer pattern by the photolithography technique.

  FIG. 3 is an explanatory diagram of a partially enlarged side cross-section obtained by performing demetalization processing (demetalizing processing) on the material of FIG. 2, and as shown in the figure, the patterned colored resin layers 7 and 8 and The metal thin film layer other than the contact portion is dissolved, and this is slit using a micro slitter and wound around a bobbin to form a thread.

  Furthermore, paragraph [0080] of Patent Document 9 uses the expression resin printed layer (7, 8) colored in the same meaning as the colored resin layers 7, 8 (see FIGS. 2 and 3). "As a method of providing the resin printed layers (7, 8) colored on both the front and back surfaces of the base material (2), a resin whose surface (front side) is colored first on a base material on which metal is vacuum-deposited on both sides in advance. A method in which a printed layer (7) is provided, followed by a colored resin printed layer (8) and then a demetalizing process, or vice versa, that is, on a substrate on which metal has been vapor-deposited on both sides in advance. "A method of first providing a colored resin printed layer (8), then providing a colored resin printed layer (7) and then demetalizing" can be adopted. First, the surface of the substrate on which the metal is deposited is colored. The resin printed layer (7) is provided, followed by a demetalizing process, and then a colored resin printed layer (8) is provided on the surface opposite to this surface, and then the demetallizing process is performed. It can be done ".

  When manufacturing the thread of the invention of Patent Document 9, when the positional relationship between the pattern formed on the surface of the base material and the pattern formed on the back surface of the base material may be at random, It is not necessary to consider the printing position when printing the pattern to be formed. However, when the positional relationship between the pattern formed on the surface of the base material and the pattern formed on the back surface of the base material is not good at random, for example, a thread such as that illustrated in FIG. In the case of patterning, it is necessary to control the positions of the patterns formed on the front and back sides at the time of printing so that they are accurately arranged at predetermined positions. However, Patent Document 9 does not propose a specific method.

  The problem to be solved by the present invention is to specifically control the relative position between the front and back patterns of the layer of the patterned metal thin film layer and the colored resin layer respectively formed on the front and back of the thread. It is providing the manufacturing method of the thread | thread which has a means.

  In order to achieve the above object in the present invention, the invention described in claim 1 is a method for producing a thread-like or belt-like thread having front and back surfaces, wherein a metal thin film layer is formed on both surfaces of a light-transmitting substrate. A patterned metal thin film layer is formed by forming a colored resin layer on the metal thin film layer in a pattern, and etching the metal thin film layer using the patterned colored resin layer as an etching mask. And a colored resin layer are formed on both sides of the light-transmitting substrate, and then a light-transmitting substrate having a layer on which both the patterned metal thin film layer and the colored resin layer are overlapped is formed on the thread. In the manufacturing method of the thread | sled cut | disconnected in width | variety, when forming the said metal thin film layer, the light transmissive part which does not provide a metal thin film layer on both surfaces is provided in a part of light transmissive base material, and the said colored resin layer When forming a pattern Te, a thread producing method, which comprises forming a pattern while performing the front and back of the relative positions confirmed the colored resin layers on both surfaces of the light-transmitting portion.

  The invention according to claim 2 is characterized in that the light-transmitting substrate is in a web-like form, and the light-transmitting portion is provided at an end in the width direction of the light-transmitting web-shaped substrate. The method for manufacturing a thread according to claim 1.

  The invention according to claim 3 is the thread manufacturing method according to claim 1 or 2, wherein the patterned colored resin layer is formed by a printing method.

  Since this invention is the above structure, there exist the following effects.

  In the manufacturing method of the thread, in the manufacturing method of the thread, in order to accurately control the relative position between the pattern of the front and back in the layers of the patterned metal thin film layer and the colored resin layer respectively formed on the front and back of the thread, Since the pattern is formed in a state where the front and back patterns can be seen through the light transmitting portion, it is possible to provide a high-quality thread in which the relative positions between the front and back patterns are optimally matched.

  According to a second aspect of the present invention, the colored resin layer that is directly formed on both surfaces of the light transmitting portion and used for confirming the relative positions of the front and back surfaces is formed at the end in the width direction of the web-like substrate. Therefore, in the cutting step, which is the final step of the thread manufacturing method, the light transmitting portion in which the colored resin layer is directly formed on the front and back sides is easily cut off, and only the portion used as the thread is efficiently collected for forgery. Can be used for prevention paper. In addition, it is easy to manufacture by forming a light transmitting portion at the end in the width direction of the web substrate as a position to selectively provide a light transmitting portion where the metal thin film layer is not partially provided at the same place on the front and back sides. It is easy to realize.

  According to the invention of claim 3, the process of forming the patterned colored resin layer is short and reliable, and does not increase the manufacturing cost. Moreover, since the relative positions of the front and back patterns can be easily confirmed, the quality can be easily maintained.

  Further, the thread obtained by the manufacturing method of the present invention has the same structure as that of the thread previously proposed by the present applicant in Patent Document 9 (WO2007 / 007784A1). Therefore, the thread can be obtained by the manufacturing method of the present invention. The anti-counterfeit paper in which the thread is inserted between the paper layers can be expected to have the same effect as in Patent Document 9. That is, a colored image of a pattern such as a micro character of a thread that can be visually recognized from one surface (for example, the front surface) with reflected light cannot be visually recognized (or difficult to visually recognize) by the reflected light from the opposite surface (for example, the back surface). Since this overturns the expectation that something should be seen, of course, it can be expected to be effective as a contrivance for anti-counterfeiting measures and as a contrivance for giving fun as a sense of fun. The reason for the above appearance is that when viewed from the opposite side, the metal thin film layer located on the viewer's side reflects light in the paper, and as a result, the patterned metal thin film layer and This is because the colored layer looks as if it does not exist there. In this case, when the paper or the printed material is observed with transmitted light under light, an effect of visually recognizing an image shadowed by the micro character or the like can be obtained. The present invention has an effect that the thread proposed in Patent Document 9 (WO2007 / 007784A1) having these excellent effects can be efficiently manufactured with high quality as described above.

Furthermore, when the front and back both sides of the window empty thread paper using the thread manufactured by the manufacturing method of the present invention is applied to the front and back both sides of the front and back sides of the front and back sides of the front and back sides of the paper, it is used for applications such as passports. This is effective for the case where anti-counterfeiting measures are always required on the front and back pages. Also, for transparent items such as various tags printed on both front and back sides, transparent cases for CDs and DVDs, transparent packaging films for packaging branded products, transparent sake bottles, etc. It can be suitably used for a label (so-called brand protection label) for pasting and certifying the authenticity of the article, and exhibits an excellent anti-counterfeiting effect.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 4 is a plan view schematically showing a material for producing a thread by the production method of the present invention, and is formed on the surface (front side) of the substrate 2 having a web shape and light transmittance. A state in which the colored resin layer 7 is formed on the metal thin film layer 3 is shown. As shown in the figure, the metal thin film layer 3 is provided near the center of the base material, leaving the light-transmitting portions B at both ends in the width direction of the base material 2, and the colored resin layer 7 is formed on the metal thin film layer 3. Are also formed on the light-transmitting portion B.

  FIG. 5 is a partially enlarged cross-sectional view taken along the line AA ′ of the sheet shown in FIG. 4. The metal thin film layer 3 is applied to the surface of the base material 2, and the colored resin layer 7 is patterned thereon. Has been. On the back surface, a colored resin layer 8 is patterned on a metal thin film layer 4 not shown in FIG. In this embodiment, the colored resin layers 7 and 8 are printed with a desired pattern such as a micro character. However, the pattern forming method is not limited to the printing method, and a general process including exposure and development steps is used. It is also possible to form a pattern by a photolithography technique.

  Here, the metal thin film layers 3 and 4 are good examples of metal vapor deposition layers, and metal is formed by a vacuum vapor deposition method. In the example of this embodiment, it is easy to obtain appropriate light shielding properties and light reflectivity. In consideration of the workability or cost, it is optimal to use metallic aluminum. In addition, for the film formation of the metal thin film layer of the present invention, other film forming techniques such as a sputtering method and an ion plating method may be appropriately used as necessary.

  When forming the metal thin film layers 3 and 4 on both surfaces of the base material 2 that is web-like and light transmissive, as a method of providing the light transmissive portion B in the flow direction of the base material 2, a metal is vacuum-deposited. When forming a film by the method of using a shielding plate so that the end in the width direction of the web-like base material is not deposited, or water-soluble resin is continuously applied to the end in the width direction of the front surface and the back surface of the base material in advance. Alternatively, it is intermittently applied or printed, and then vacuum-deposited on the entire surface of both sides of the substrate to provide a metal thin film layer, and then the substrate is washed with water to elute the water-soluble resin and simultaneously on the surface of the water-soluble resin. A method such as a method of removing the formed metal thin film layer can be appropriately employed. In addition, the edge part of the width direction of a web-shaped base material does not point out the end surface of a base material by a strict meaning, but points out the area | region from the position cut | disconnected in the width direction of the web-shaped base material to a fixed distance inside. This means that if the region is suitable for the purpose of forming the light-transmitting portion in the present invention, the size of the region is appropriately determined depending on the practical form.

  In the present invention, after the metal thin film layers 3 and 4 are provided, the colored resin layer 7 is printed on the light-transmitting portion B on one surface of the substrate 2 and the metal thin film layer 3 as shown in FIG. A desired pattern is formed by the method. Next, the colored resin layer 8 is formed in a desired pattern on the other surface of the light-transmitting portion B and the metal thin film layer 4 (on the back side and not shown in FIG. 4) by a printing method. At this time, referring to the position seen from the back surface of the colored resin layer 7 formed on the light-transmitting portion B of the light-transmitting base material 2, the colored resin layer 8 is formed in a pattern at a predetermined target position. To print.

The colored resin layers 7 and 8 are formed by forming an ink mainly composed of a colorant and a resin into a desired pattern using an appropriate printing technique. In the present invention, the colorant is a material that can have a contrast to such an extent that a desired pattern can be discriminated. For example, when the paper is colored, titanium oxide, barium sulfate, kaolin, calcium carbonate, etc. Scattering pigments are also colorants. In the present invention, the colorant may be a material having absorption in a specific wavelength region other than the visible region, in addition to a pigment or dye that appears colored in the visible region. For example, in order to use an ultraviolet absorber or an infrared absorber as a coloring material in the present invention, a desired pattern may be observed with an ultraviolet monitor or an infrared monitor. In the present invention, it is also possible to use a material that excites at a specific wavelength and fluoresces, phosphorescents, or stores light in a wavelength region other than the specific wavelength. For example, there are materials that excite in the ultraviolet region and emit light in the visible region, materials that excite in the visible region and emit light in the infrared region, and materials that excite in the infrared region and emit light in the visible region. Moreover, in this invention, the material which has birefringence which can be visualized by observing through a polarizing plate or a phase difference plate may be sufficient. Moreover, it is also possible to improve security by using the different coloring materials in combination.

  The colored resin layers 7 and 8 can be provided by a known printing technique such as offset printing, gravure printing, screen printing, flexographic printing, and ink jet printing. When printing a colored resin layer, a pattern is printed at a predetermined position by appropriately controlling the tension of a web-like and light-transmitting substrate supplied from a roll or adjusting the pattern of a printing plate. be able to. The printing thickness of the colored resin layer is usually 0.5 μm to 3 μm. When the print pattern is a micro character, it is usually preferable to use a size corresponding to 2 to 10 points. As described above, the pattern forming method is not limited to the printing method, and it is also possible to form the pattern by a general photolithography technique including exposure and development steps.

  Next, by using the patterned colored resin layers 7 and 8 as a mask for etching resistance, the metal thin film layers 3 and 4 are etched (that is, demetallized) with an acid or alkali aqueous solution, thereby similar to FIG. Thus, a sheet is obtained in which the metal thin film layer and the colored resin layer are formed so as to overlap in the same pattern. In order to use the printed colored resin layers 7 and 8 as an etching-resistant mask when patterning the metal thin film layers 3 and 4 by etching, the coloring material of the printed colored resin layers 7 and 8 and As a material such as a resin, it is necessary to select a material that is not easily affected by the etching solution. In addition, if the etching solution penetrates into the interface between the metal thin film layers 3 and 4 and the colored resin layers 7 and 8, the patterning accuracy is adversely affected. To prevent this, the metal thin film layer and the colored resin are used. It is preferable to appropriately select a material or a film forming method with good adhesion between the layers.

  Subsequently, an adhesive is applied to at least one side of the sheet as necessary, and slits are formed into a thread or a belt according to a conventional method using a micro slitter, and wound on a bobbin to produce the thread of the present invention.

Hereinafter, the present invention will be described in more detail on the premise of threads used for forgery prevention paper.
The web-like and light-transmitting substrate 2 is cellophane, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyacetal, polyphenylene ether, liquid crystal polymer, polyvinyl chloride, polyester, polyamide, polycarbonate, polyethyl methacrylate, polystyrene, etc. These semi-synthetic or synthetic resin films can be used as a single layer or a composite. Further, it is preferable to select a material that does not melt or soften in the drying zone of the paper machine, and usually has a property of not sticking at 90 to 110 ° C. If the thickness of the base material is too thin, various processing becomes difficult, and if it is too thick, the paper thickness will partially increase and cause various problems when threads are made between the paper layers. The thickness of is preferably 5 μm to 25 μm.

  In the state of the anti-counterfeit paper or the anti-counterfeit printed matter in which the thread is engraved between the paper layers, it is preferable that the presence of the base material 2 cannot be visually recognized from the appearance. Can be mentioned. Even a very lightly colored chromatic substrate can be used if the object of the present invention can be achieved. In the present invention, as a representative example, a transparent polyester film having a large physical strength and being chemically stable can be suitably used.

Also, a translucent base material subjected to sandblasting is preferably used when the paper color is white or close to white because the presence of threads engraved between the paper layers cannot be visually recognized under reflected light. It is necessary for the base material to be transparent in order to observe the transmitted letters and to see the reverse letters from the surface. In the present invention, the term “transparency” does not necessarily mean that transparency is 100%, and it means that the numerical value of transparency may be somewhat low as long as the object can be achieved. This is also related to the color of the ink printed around the paper or the thread of the printed material, etc., and the transparency may be adjusted as appropriate.

  It is preferable to give the base material 2 the property of absorbing ultraviolet rays. The reason is that, as described later, as a means for judging the front and back of the thread, a dye or pigment that emits light when irradiated with ultraviolet rays is used in combination with the adhesive, and ultraviolet rays are irradiated on the thread during paper manufacture to judge the front and back of the thread. In this case, if the base material 2 does not absorb the ultraviolet light, the ultraviolet light is transmitted through the base material between the metal vapor-deposited layers removed by the demetalization process, and both sides of the thread are emitted and observed, so that the front and back of the thread can be determined. It will be difficult.

  In order to give such a property to the base material 2, it is necessary to knead an ultraviolet absorbent at the time of manufacturing the base material, or to provide a coating layer that absorbs ultraviolet light in advance on the surface of the base material, or after demetallization processing. Any well-known means can be adopted. As UV absorbers, all well-known UV absorbers such as benzophenone, triazine, triazole, salicylic acid, hydroquinone, amine, ultrafine metal oxides such as zinc oxide and titanium oxide are used. can do. The addition amount of the ultraviolet absorber is usually 0.01 to 5% by mass with respect to the substrate.

  As a method for forming the micro characters on the base material 2, there is a demetallization process. This demetallization process is a well-known method (for example, Japanese Translation of PCT International Publication No. 2005-513585). In the present invention, for example, a resin ink having alkali resistance and acid resistance on a substrate 2 on which metal aluminum is vacuum-deposited is used. After adding dyes such as red, indigo, yellow, black, white, etc., or a colorant of a single or mixture, printing a pattern of micro characters, etc. to form colored resin layers 7 and 8, an alkaline aqueous solution or an acidic solution A method of washing away the vapor deposition layer of aluminum other than the printing portion with an aqueous solution can be employed. The metal used for this vapor deposition layer is typically the above-mentioned aluminum, but in addition to this, a simple substance or a mixture of metals such as tin, zinc, iron, nickel, chromium and cobalt can be used. In particular, by forming at least one of the micro character strings as a deposited film of a magnetic material such as nickel-cobalt, the magnetic information can be used as a forgery preventing means. The thickness of the metal vapor deposition layer is usually 25 to 100 nm.

  In the present invention, after the above-described treatment is performed on the substrate 2, a protective layer is applied to improve the chemical resistance and physical strength as necessary, or a film having excellent light transmittance is applied. Combining can be performed as appropriate.

Next, an adhesive is applied to one side or both sides as necessary to form an adhesive layer. Adhesives are well-known adhesives that have the ability to soften or melt with paper machine dryers and adhere firmly to paper, specifically polyvinyl acetate resin, polyvinyl chloride resin, polyester resin Water-based or solvent-based well-known adhesives such as polyacrylic ester resin-based, ethylene-vinyl acetate copolymer resin-based, and polyvinyl alcohol resin-based can be used. One or more of these adhesives are coated on the surface of the substrate using a known coating machine such as a roll coater or gravure coater to form an adhesive layer. The coating amount is usually 0.1 to 10 g / m ² (in terms of dry mass).

The thread coating paper of the type in which the thread is buried between the paper layers may have a small coating amount of the adhesive, but the coating amount is increased in the case of the paper with a window thread. If necessary, an anti-blocking agent, a lubricant, a colorant, a fluorescent color former and the like may be added to the adhesive. As mentioned before, when it is necessary to determine the front and back of the thread, use a base material that absorbs ultraviolet rays as the base material, add a fluorescent color former to the adhesive, and apply this adhesive only to one side. By manufacturing the coated thread, the front and back of the thread can be easily determined by the presence or absence of light emission of the thread by irradiation of ultraviolet rays.

  It is then slit using a micro slitter device to complete the thread of the present invention. The width of the thread is usually in the form of a thread or strip having a width of 0.5 mm to 10 mm. The micro characters formed on the thread need to be formed so that one or more rows of regular characters and regular patterns can be visually recognized.

  The anti-counterfeit paper using the thread manufactured by the manufacturing method of the present invention will be described. As described above, the thread obtained in the present invention can be suitably used for any type of threaded paper in which the thread is buried between paper layers or paper with a window open thread.

  FIG. 6 explains the threaded anti-counterfeit paper having the same contents as the figure illustrated as FIG. 1 in Japanese Patent Laid-Open No. 2001-172897 previously proposed by the present applicant. An explanatory plan view of the anti-counterfeit paper 20, (B) shows a cross-sectional explanatory view along line XX. In the present invention, a thread 21 sandwiched between sheets is exposed on the front and back surfaces of a plurality of paper windows 22, 22a, 22b opened by removing a part of the paper layer 23 on the front and back sides of the paper. In addition, the anti-counterfeit paper with threads is characterized by being visible like a thread (front) 21a and a thread (back) 21b. In paragraph [0019] of Japanese Patent Application Laid-Open No. 2001-172897, “In the present invention, since one thread can be seen from the front and back of the paper, it is possible to enhance security on both the front and back, and the price remains the same. In particular, when using front and back pages such as a passport, the present invention is effective against a case where anti-counterfeiting is always required on the front and back pages. " The same effect can be expected by using the thread according to the manufacturing method of the present invention.

  Further, FIG. 7 of EP0229645B1 exemplifies the same content as the cross-sectional explanatory diagram of the forgery prevention paper shown in FIG. In the right column (column 6) 14-32 lines of the above-mentioned EP0229645B1, the paper layers 33 and 35 in FIG. It is stated that it is manufactured. A thread 37 is inserted into the windows (hole pattern, 30 and 31 in FIG. 7) provided on the front and back sides of the paper, and the thread can be visually recognized from the windows provided on the front and back surfaces. The window is formed so that the windows overlap when both webs are stitched together, and when the thread is exposed at the same location on both sides (not shown in the publication), the window is zigzag inside both paper layers. It is described that it may be formed so as to be displaced (FIG. 7), and the same application is possible even if a thread by the manufacturing method of the present invention is used.

  The thread obtained by the production method of the present invention can also be suitably used for paper with a window empty thread in which windows are formed on the front and back of the paper as exemplified in the above-mentioned JP-A No. 2001-172897 and EP0229645B1. . The pattern (for example, micro characters) formed on the thread exposed on the window on the front (front side) of these papers is different from the pattern formed on the thread exposed on the back window. However, it is expected that the anti-counterfeiting effect will be much higher and the design effect will be higher than in the case of the same pattern as in the conventionally known thread, while the thread manufacturing method of the present invention has a light shielding effect. Since it is advantageous for alignment of the front and back while having it, it is particularly suitable for making threads of various forms as described above.

Hereinafter, specific examples of the thread manufacturing method of the present invention will be described.
<Example 1>
(See FIGS. 4 and 5 as a conceptual diagram)
Formation of metal thin film layer (production of evaporated film)
As a base material, a winding of a transparent polyester film (trade name “Lumirror”, manufactured by Toray Industries, Inc.) having a width of 500 mm and a thickness of 12 μm is used, and metal aluminum is vacuum deposited on both the front and back surfaces by 50 nm (nanometers). Was deposited according to a conventional method to form a metal thin film layer. Under the present circumstances, it vapor-deposited using the shielding board, leaving the light transmissive part which is not vapor-deposited in each 20 mm of both ends of the width direction of a film.

Prescription of colored resin layer ink Prescription of blue ink Alkali-resistant resin ink (acrylic resin for demetalization): 100 parts by weight Blue dye (trade name “Oreosol Blue” manufactured by Sumitomo Chemical Co., Ltd.): 20 parts by weight Organic solvent: Appropriate amount Red ink formulation Alkali resistant resin ink (acrylic resin for demetallization): 100 parts by weight Red dye (trade name "Oreosol First Red", manufactured by Sumitomo Chemical Co., Ltd.)
: 15 parts by mass Organic solvent: Appropriate amount.

Formation of colored resin layer Next, using a gravure printing machine, a colored resin layer was formed on both front and back surfaces of the deposited film. On the gravure roll of the gravure printing machine, letters of “★ ABCD △△△△△△” (△ is a space) are engraved in parallel by the corrosion method, and the size is 2.5 points (points) The number means the number of American points, and one point is about 0.35 mm), the distance between characters is 0.4 mm, and the distance between characters is 0.8 mm. Using this gravure roll, using the blue ink, printing was performed on the entire surface of the vapor-deposited film to form a colored resin layer composed of micro characters having a dry thickness of 2.5 μm.
Subsequently, using the same gravure roll, it printed using the said red ink on the back surface of a vapor deposition film, and formed the colored resin layer which consists of micro characters with a dry thickness of 2.5 micrometers.
At this time, the character string printed on the front surface is the same as illustrated in FIG. 4 so that the character string printed on the back surface and the front and back overlap in one row, and the character string is “★ ABCD △” (△ is a space). Next, printing was performed while adjusting the tension of the film and the position in the width direction so that a symmetrical character string could be entered. This adjustment can be easily performed by observing transmitted light during printing or by observing a strobe image because the light transmissive portions B are provided at both ends of the substrate.

Demetallization processing (paster processing)
Then, according to a conventional method, using a sodium hydroxide aqueous solution, it was subjected to demetallization processing, washed with water, dried, and wound up on a roll.

Application of Adhesive Further, an ethylene-vinyl acetate heat-sensitive adhesive was applied on one side with a thickness of 1.5 μm using a gravure coater to form an adhesive layer.

Production of Thread Next, the above-mentioned film was subdivided into a width of 150 mm using a slitter, and then a 2 mm wide thread was produced using a micro slitter and wound on a bobbin.

<Example 2>
(See Fig. 8 as a conceptual diagram of the original version)
Formation of metal thin film layer (production of evaporated film)
As a base material, a transparent polyester film having a width of 500 mm and a thickness of 12 μm (trade name “Diafoil”, manufactured by Mitsubishi Plastics Co., Ltd.) is used, and metal aluminum is vacuumed by 60 nm (nanometers) on both front and back surfaces. A metal thin film layer was formed by vapor deposition according to a conventional method using a vapor deposition machine. Under the present circumstances, it vapor-deposited using the shielding board, leaving the light-transmitting part B which is not vapor-deposited in each 15 mm of both ends of the width direction of a film.

Colored resin layer ink formulation Blue ink formulation (for blue UV fluorescent mask layer)
Blue UV curable ink (trade name “UVBFWRO Ai”, T & K Toka Co., Ltd.)
Production): 30 parts by mass Medium (trade name “UV Fluorescence Medium Y”, manufactured by T & K Tohka Co., Ltd.)
: 70 parts by mass)
Red ink formulation (for red mask layer)
Red UV curable ink (trade name “UVBFWRO red”, T & K Co., Ltd.
Donghua Manufacturing).

Formation of colored resin layer Subsequently, an offset printing machine was used to form colored resin layers on both the front and back surfaces of the deposited film. As shown in FIG. 8, the offset printing blue original plate is made of characters of “★ ABCD ΔΔΔΔΔΔ” (Δ is a space) continuously in parallel, and the size is 2.5. Points (the number of points means the number of American points, one point is about 0.35 mm), the distance between characters and characters was 0.4 mm, and the distance between characters and characters was 0.8 mm. Further, in order to print alignment marks on the light-transmitting portions B at both ends in the width direction of the web-like substrate surface (front surface), the upper and lower positions are aligned on the blue original plate of FIG. A mark 9 was provided. Using the blue UV curable ink, a colored resin layer was printed on the surface (front side) of the substrate as micro characters corresponding to the blue original plate and alignment marks.
Next, the red master for offset printing has a space in the “★ ABCD” position of the blue master, and “★ ABCD” is placed in the “△△△△△△” (space) position of the blue master. In order to print the alignment marks on the light-transmitting portions B at both ends in the width direction of the web-like base material back surface, each of the upper and lower portions on the red original plate in FIG. The alignment mark 9 was provided at the same location as the blue original. Using the red UV curable ink, a colored resin layer was printed on the back surface of the substrate as micro characters and alignment marks corresponding to the red master. At this time, the colored resin layer was printed while adjusting the film tension and the position in the width direction and the flow direction so that the alignment marks on the front surface and the back surface were completely matched. The printing position adjustment can be easily performed by observing the transmitted light or observing the stroboscopic image because the light transmissive portions B are provided at both ends in the width direction of the substrate.

Demetallization processing (paster processing)
Then, according to a conventional method, using a sodium hydroxide aqueous solution, it was subjected to demetallization processing, washed with water, dried, and wound up on a roll.

Application of Adhesive Further, on one surface, a polyester urethane type heat-sensitive adhesive was applied with a thickness of 2 μm using a roll coater to form an adhesive layer.

Production of Thread Next, the film was subdivided into a width of 150 mm using a slitter, and then a 2 mm wide thread was produced using a micro slitter and wound on a bobbin.

  As described above, according to the method of the present invention, the thread previously proposed by the present applicant in WO2007 / 007784A1 can be manufactured with high accuracy by a novel method that has never existed. Since the thread obtained by the method of the present invention utilizing this characteristic requires a very advanced technique, it can be suitably used for the use of a sewing thread for the purpose of preventing forgery. In addition, the anti-counterfeit paper incorporating the thread obtained by the method of the present invention should be suitably used for banknotes, gift certificates, checks, stock certificates, bonds, cards, various tickets, confidential documents, passports, identification cards, etc. Can do.

It is a plane explanatory view showing typically the material for manufacturing a thread. It is explanatory drawing of the partially expanded side cross section of FIG. It is explanatory drawing of the partially expanded side cross section which gave the metallization process to the material of FIG. It is plane explanatory drawing which shows typically the material for manufacturing a thread | sled with the manufacturing method of this invention. FIG. 5 is an explanatory diagram of a partially enlarged cross section taken along line A-A ′ of the sheet illustrated in FIG. 4. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a threaded forgery prevention sheet, where (A) is a plane explanatory view and (B) is a cross-sectional explanatory view taken along line XX. It is sectional explanatory drawing for demonstrating the forgery prevention paper containing a thread | sled. FIG. 6 is an explanatory diagram for explaining Example 2;

Explanation of symbols

2... Web-like substrate 3 with light transmission 3 Metal thin film layer 4 Metal thin film layer 7 Colored resin layer 8 Colored resin layer 9 Position alignment mark B Light transmission Sexual part 20: Anti-counterfeit paper 21 ... Thread 21a..Thread (table)
21b. Thread (back)
22 ... Paper window 22a ... Paper window (front)
22b..Paper window (back)
23 ... paper layer 30 ... window 31 ... window 33 ... paper layer 35 ... paper layer 37 ... thread

Claims (3)

  A method for producing a thread-like or belt-like thread having front and back surfaces, forming a metal thin film layer on both surfaces of a light-transmitting substrate, forming a colored resin layer in a pattern on the metal thin film layer, Using the patterned colored resin layer as an etching mask, the metal thin film layer is etched to form overlapping layers of the patterned metal thin film layer and the colored resin layer on both surfaces of the light-transmitting substrate. Then, in forming the metal thin film layer in the thread manufacturing method of cutting the light-transmitting substrate having the overlapping layer of the patterned metal thin film layer and the colored resin layer on both surfaces into the width of the thread, When the light-transmitting substrate is provided with a light-transmitting portion where no metal thin film layer is provided on both surfaces, and the colored resin layer is formed in a pattern, the colored resin layer is formed on both surfaces of the light-transmitting portion. The relative position of the front and back Thread method for producing and forming a pattern while performing certification.   2. The thread manufacturing method according to claim 1, wherein the light-transmitting substrate has a web-like form, and the light-transmitting portion is provided at an end portion in a width direction of the light-transmitting web-shaped substrate. Method.   The thread manufacturing method according to claim 1 or 2, wherein the patterned colored resin layer is formed by a printing method.

Images