WO2008078949A1

WO2008078949A1 - Functional fiber for preventing forgery

Info

Publication number: WO2008078949A1
Application number: PCT/KR2007/006806
Authority: WO
Inventors: Ku Won Seo; Won Gyun Choe; Sun Young Kim; Soo Dong Kim; Hong Sub Choi; Sang Geun Lee; Sun Hong Yoon
Original assignee: Korea Minting And Security Printing Corp
Priority date: 2006-12-27
Filing date: 2007-12-24
Publication date: 2008-07-03
Also published as: JP2010514950A; GB0910992D0; RU2009128649A; GB2458591B; RU2415205C1; GB2458591A; DE112007003170T5; US20090311527A1

Abstract

The present invention relates to a functional fiber for preventing forgery, more particularly functional fiber for preventing forgery which exerts functionality by mixing special pigments to composite fibers of side by side shape on which two components are attached. The functional fibers of two components structure according to the present invention are consisted of synthetic high molecules, and have functionality which fibers display color by colored pigments with visual or fluorescence by light of ultraviolet ray or absorbing property of infrared pigments by being produced by mixing colored pigments, fluorescent pigments, infrared pigments and the like to each resin, and then melt-spinning the said mixture, or post treating it. While such fibers according to the present invention are hard to have a property of fibers since those contain pigments above a specific concentration, the fibers have functionality for preventing forgery by mixing a monofilament which is obtained by cutting the said fibers to papers, resins of high molecules, or coating agents so that it can be used as a functional element for preventing forgery and identifying authenticity of particular product demanded security such as a bank bill, a bond, a passport, an identity card.

Description

Description FUNCTIONAL FIBER FOR PREVENTING FORGERY

Technical Field

[1] The present invention relates to a functional fiber for preventing forgery, more particularly functional fiber for preventing forgery which exerts functionality by mixing special pigments to composite fibers of side by side shape on which two components are attached. Background Art

[2] A proposed technique as a functional fiber for preventing forgery in conventional art may be described as folio wings;

[3] A fiber having fluorescence functionality has been produced by using method which produces a fiber by melting or dispersing fluorescent pigment or fluorescent dye whose external color is white or colored into synthetic resins for a fiber and then ejecting the resultant mixture, or fixing fluorescent dye on a surface of fiber with reaction, or preparing paints or inks with fluorescent pigment or fluorescent dye and then painting and coating the obtained paints or inks on a fiber. With the techniques relevant to the said one, Japanese patent early publication No. Sho 63-196719(1988), Japanese patent early publication No. Sho 63-165517(1988) and Japanese patent early publication No. Pyung 2-200811(1990) can be presented.

[4] While the paper produced by adding a monofilament obtained from such fiber having fluorescence functionality in a paper-procedure can not be observed in naked eye, the monofilament can be easily observed provided that the produced paper is exposed under a fluorescent lamp, namely ultra violet, because it is excited, so that it functions effect for preventing forgery by differentiation from conventional papers.

[5] A proposed technique to improve the above-mentioned fluorescence functionality may be also described as folio wings;

[6] Korean patent registration No. 0109762 (title; Silver thread of two definite colors and preparing method thereof, and counterfeit prevented paper using the same and producing method thereof) discloses a fiber for preventing forgery that displays a visual colors different with a fluorescent colors by the first pigmentation and then the second pigmentation with a fluorescent dye which is expressed whit the other color.

[7] Korean patent registration No. 0259825 (title; Security paper with silver thread with strips of many colors and the manufacturing process) discloses a fiber for preventing forgery which produces a thread with strips of many colors of shape of a cloth with strips of many colors by cutting the fiber that is obtained as a state of one whose inside is not dyed and whose outside is dyed by pigmentation at state twisted a mix-treaded fiber.

[8] Korean patent registration No. 0363720 (title; Phosphorescent and fluorescent synthetic resin of invisible two colors, its preparing and using method) discloses a fiber for preventing forgery which displays fluorescent radiation when being outside stimulus such as exposure of ultra violet and displays phosphorescent radiation when being removed an outside stimulus, since the said fiber includes all phosphorescent matters and fluorescent maters having a different radiating wavelength from each other, and whose appearance is with white color or without any colors.

[9] Korean patent registration No. 0407251 (title; Two colored fiber, method for preparing the same and wertpapier and passport containing the same) discloses a two colored single fiber which is produced to be differentiated a central color with a color of the both end by removing an inside ingredient with dissolving it only by dipping a short fiber into a solvent which dissolve only an inside ingredient, the said short fiber being obtained by preparing a composite fiber of sheath-core type consisted of an outside ingredient and an inside ingredient.

[10] The above mentioned functional fiber have been all a fiber type obtained by one- axial weaving (monofilament), and its functionality or each feature is allowed by mixing colored pigments, fluorescent pigments and the like during a procedure of producing a fiber, or by dyeing and pigmentation during a procedure after producing a fiber.

[11] The method of manufacturing a composite fiber has been developed to endow a winding property for a fiber that is a side by side type being relevant to the present invention. The proposed technique may be described as followings to relate to the above method;

[12] According to U.S patent No. 3454460(1969) and Japanese patent early publication

No. Sho 51-67421, these inventions allow a winding property of high level by means of simultaneous spinning a polyester having two component whose physical property are different each other, through the spinneret which is arranged with a side by side type. Korean patent registration No. 0087989 (title; Manufacturing process for polyester composite fiber having a spontaneous winding property of high level) and Korean patent registration No. 0407373 (title; Manufacturing process for elastic composite fiber of polyesters) disclose a manufacturing process for composite fiber having a winding property of high level by spinning a polymer consisted of two kinds and whose intrinsic viscosity are different each other, and elongating and then heat- treating according to a conventional process.

[13] Korean patent registration No. 0234558 (title; Manufacturing process for mixed yarn having different shrinkage) discloses a mixed yarn having different shrinkage having a touch sensation of an micro powder by mix-treading a undrawn yarn of two type polyester whose spinning velocity is different each other, and Korean patent registration No. 0245664 (title; Spontaneous winding fiber of a side by side type of an excellent interface adhesive property and winding property) discloses a fiber having an excellent interface adhesive property which is interlocked a part of one component with the other component between the interface of two component with improvement of a ejaculating device for spinning when producing a composite fiber of a side by side type.

[14] Also, Korean patent registration No. 0602284 (title; Preparation of side by side type polyester composite fiber and side by side type polyester composite fiber) discloses a composite fiber which resolves a high-angle firing problem at spinning and further has an excellent winding property without improvement of a spinning device by mix- spinning a polymer of two kinds whose intrinsic viscosity are different each other, Korean patent registration No. 0429364 (title; Method for manufacturing dibasic polyester-conjugated yarn having improved size stability) discloses a fiber having a good dibasic effect and improved size stability by mix-spinning two components of basic dye dying polyester and basic dye non-dying polyester, Korean patent registration No. 0403766 (title; Method for producing non- woven fabric using highly- contractive composite monofilament) discloses a method for producing an ultra fine non- woven fabric by preparing a composite monofilament having a divided section by mix- spinning polymers of two types different each other.

[15] Korean patent registration No. 0259825 (title; Security paper with silver thread with strips of many colors and the manufacturing process) discloses a fiber for preventing forgery which produces a thread with strips of many colors of shape of a cloth with strips of many colors by cutting the fiber that is obtained as a state of one whose inside is not dyed and whose outside is dyed by pigmentation at state twisted a mix-treaded fiber, and a monofilament occasionally shows a shape of J due to a dyeing process by a mix-treaded fiber.

[16] The above described techniques have an object that the composite fibers of a side by side type on which two components are attached is to improve property of fibers for textiles such as winding property, interface adhesive property, touch sensation, size stability and the like.

[17] However, as the consequence of the above investigation and review for the scrutinized prior art, we know that a fiber for identifying authenticity, preventing forgery or functionality is the type of one-axial spinning, and a form of monofilaments is monotonous and irregular so that an effect of preventing forgery is weak. Disclosure of Invention Technical Problem [18] The present invention is created to supplement the above-mentioned drawback in the prior art. Therefore, object of the present invention is to provide a fiber for preventing forgery that an effect of preventing forgery and functionality are reinforced by adding a property of colored pigments, fluorescent pigments, infrared pigments and the like into inside or outside of composite fibers having a side by side type.

[19] Another object of the present invention is to provide a fiber for preventing forgery that the composite fibers having a cross section of a side by side type is produced by melting and spinning a master batch of at least two kinds obtained by mixing a functional pigment to resins which have different melting point each other, and then cooled with heat treatment at thermal deformable temperature of the said resins, thereby occurring flexing or contraction according to a physical property of the resins. Technical Solution

[20] To achieve the said object, the present invention provides a fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery is produced by heating and mixing the first ingredient and the second ingredient of a form of chip made of synthetic high molecules to melt- spine it and then introducing a special pigment with a dyeing method.

[21] Or, according to the present invention, in a fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery is produced by preparing a master batch for melt-spinning which is produced by adding a special pigment to any one of the first ingredient and the second ingredient of a form of chip made of synthetic high molecules and then heating and mixing, and heating and mixing the said master batch with the other one ingredient to melt- spine it, and then introducing a special pigment with a dyeing method.

[22] Polyester, nylon, polypropylene, polyethylene and polyurethane may be used which are enable to melt and spine as the synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers.

[23] Also, the synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers may be used with what the first ingredient and the second ingredient are same or different due to mixing property of a special pigment.

[24] Although colored pigments, fluorescent pigments, infrared pigments and the like is used as a special pigment being mixed to the synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers, it is possible for a monofilament to have a various effect in visible ray, ultraviolet ray, infrared ray and the like by blending a special pigment differently to the synthetic high molecules of the first ingredient and the second ingredient.

[25] With the other embodiment of the present invention, in a fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, the said fiber for preventing forgery may be produced such that half side displays blue and the other half side displays yellow by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Phthalocyanine Blue (CI. 74160) having blue color, colored pigment, to 95 % by weight of polyester chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 7 % by weight of Disazoyellow (CI. 21096) having yellow color, colored pigment, to 93 % by weight of polyester chip of synthetic high molecules and then by heating and mixing.

[26] With the other embodiment of the present invention, in a fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, the said fiber for preventing forgery may be produced such that red color is displayed at visible ray, fluorescent red color is displayed at ultraviolet ray of long wavelength, and fluorescent green color is displayed at ultraviolet ray of short wavelength by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Rhodamine B(CI. Basic Violet 10) having red color, colored and fluorescent pigment, to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt- spinning by adding 5 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent green color at ultraviolet ray of short wavelength to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing.

[27] With the other embodiment of the present invention, in a fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, the said fiber for preventing forgery may be produced such that white color is displayed at visible ray, red color is displayed at ultraviolet ray of short wavelength, and fluorescent green color is displayed at ultraviolet ray of long wavelength by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent blue color at ultraviolet ray of short wavelength to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent green color at ultraviolet ray of long wavelength to 95 % by weight of polyester chip of synthetic high molecules and then by heating and mixing.

[28] With the other embodiment of the present invention, in a fiber for preventing forgery that a composite fiber of side by side type being attached two components is p repared to a monofilament and it is introduced at a procedure of preparing papers, the said fiber for preventing forgery may be produced such that off-white color is displayed at visible ray, red color is displayed at ultraviolet ray of long wavelength, and black color is displayed at a region of infrared ray by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 3 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent red color at ultraviolet ray of short and long wavelength to 97 % by weight of polyester chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of infrared ray pigment whose appearance is brown and which absorbs infrared ray at region of near infrared ray to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing.

[29] With the other embodiment of the present invention, in a fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, the said fiber for preventing forgery may be produced such that red color is displayed at visible ray, red color is displayed at ultraviolet ray, and black color is displayed at region of infrared ray by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Rhodamine B having red color, colored and fluorescent pigment, to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of infrared ray pigment whose appearance is green and which absorbs infrared ray at region of near infrared ray to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing.

[30] To achieve the other object, the functional fiber for preventing forgery of the present invention is characterized in that it is produced by preparing the composite fibers having a cross section of a side by side type by melting and spinning a master batch of at least two kinds obtained by mixing a functional pigment to resins which have different melting point each other, and then by heat treating at thermal deformable temperature of the said resins.

[31] At this time, it can be used at least one selected from colored pigments, fluorescent pigments, infrared pigments as a said pigment. Therefore, it can be produced to express a different color according to wavelength of light.

[32] The said resins may be prepared by using at least one selected from polyester, nylon, polypropylene, polyethylene and polyurethane.

[33] The said master batch is consisted of two kinds, the first master batch and the second master batch whose melting temperature is different, and the said first master batch and the said second master batch may be prepared by using the same resin or different resin.

[34] The said composite fiber may be produced such that it has a cross section of a side by side type by charging a master batch of two kinds or more into each extruder for spinning and by melting and spinning it through one nozzle.

[35] The said first master batch and the said second master batch are charged into each extruder for spinning and then molten and spun it through one nozzle, thereby making it possible to produce to have a cross section of a side by side type.

[36] It is possible for the functional fiber for preventing forgery to have a special pattern by producing a monofilament with cut of the said composite fiber being molten and spun and then heat treating at thermal deformable temperature of the said resins, or by mix-spinning the said composite fiber to occur twisting at a constant length and heat treating at thermal deformable temperature of the said resins, and then cutting it to prepare with a monofilament.

[37] It is characterized in that the said special pattern is "C" type, "O" type or "S" type.

[38]

Advantageous Effects

[39] The method of manufacturing a fiber having a special pattern according to the present invention may be achieved by producing a monofilament with cutting the composite fiber of side by side type being attached two components shortly and then heat treating at thermal deformable temperature, or by mix-spinning the said composite fiber to occur twisting at a constant length and heat treating, and then cutting it shortly to prepare with a monofilament and the like, and the monofilament produced with such method may be produced with "C" type, "O" type or "S" type unlike the conventional fiber pattern, so that an effect for preventing forgery is high in case of using by mixing it to paper or sheet with a small amount.

[40] Also, it is possible to be used as an element for preventing forgery as well as for identifying authenticity of paper since a security fiber (this means a fiber which very small amounts of a functional fiber are hidden among the fibers that is a component of paper) having a various functionality such as visual color and fluorescent color, infrared ray absorbing property is observed when making the composite fiber of side by side type produced by the present invention to a short monofilament and adding its minimum amount to papers and observing under visual ray, ultraviolet ray or infrared ray. Best Mode for Carrying Out the Invention

[41] The said functional fiber for preventing forgery according to the present invention is produced by melt-spinning a special pigment being admixed to the composite fiber of side by side type being attached two components.

[42] Namely, the first ingredient of the composite fibers is prepared to a master batch for melt- spinning by adding a special pigment to a chip of synthetic high molecules and then by heating and mixing,

[43] and the second ingredient is prepared to a master batch for melt-spinning by adding a special pigment to a chip of synthetic high molecules and then by heating and mixing,

[44] and the said each master batch of the first ingredient and the second ingredient are molten and spun to produce a functional fiber for preventing forgery.

[45] The said melt-spinning of master batch of the first ingredient and the second ingredient is carried out by charging a ratio of 10-90 by weight of the first ingredient and a ratio of 90-10 by weight of the second ingredient into a extruder for spinning, and then by melt-spinning such that a diameter of fibers is 3-60D, thereby a functional fiber being produced.

[46] Polyester, nylon, polypropylene, polyethylene and polyurethane are used which are enable to melt and spine as the said synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers.

[47] The synthetic high molecules of the first ingredient and the second ingredient consisting of the said composite fibers may be used with what the first ingredient and the second ingredient are same or different due to mixing property of a special pigment.

[48] Although colored pigments, fluorescent pigments, infrared pigments and the like is used as a special pigment being mixed to the synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers, it is possible for a monofilament to have a various effect in visible ray, ultraviolet ray, infrared ray and the like by blending a special pigment differently to the synthetic high molecules of the first ingredient and the second ingredient.

[49] And, the said effect is that a monofilament displays visual color and fluorescence of ultraviolet ray, or a monofilament displays visual color and fluorescence of infrared ray, or a monofilament displays fluorescence of ultraviolet ray and absorbance of infrared ray, or a monofilament displays visual color and absorbance of infrared ray, or a monofilament displays fluorescence of short wavelength ultraviolet ray and fluorescence of long wavelength ultraviolet ray.

[50] It is possible to introduce a special pigment with a method of dyeing and pigmentation after a melt-spinning process, in stead of mixing a special pigment directly to synthetic high molecules of the first ingredient or the second ingredient of the said composite fibers. For example, the first ingredient is prepared to a master batch for melt-spinning by adding a special pigment to synthetic high molecules and then by heating and mixing, the second ingredient is prepared without addition anything to synthetic high molecules, and the said first ingredient and the second ingredient are mixed and molten-spun to prepare a monofilament, and a special pigment is introduced after dying and pigmentation process are carried out.

[51] The functional fiber of composite fiber produced by the said method may be used as an element for preventing forgery or for identifying authenticity, or used by mixing when producing a paper after making it a monofilament, or used with dispersing it into resins when producing a plastic sheet, or used with attachment on a surface of particular products by dispersing it into a coating solution.

[52] The products applied the composite fiber by the said method will be used as an element for preventing forgery and for identifying authenticity of products since a security fiber having a various functionality is observed when observing under visual ray, ultraviolet ray or infrared ray.

[53] Next is a detailed description of the present invention.

[54] As being described at the above, the present invention relates to a functional fiber for preventing forgery which exerts functionality by mixing special pigments to composite fibers of side by side type on which two components are attached, wherein it can have a functionality which make to represent a visual differentiation, fluorescent emitting colors and absorbance of infrared ray by applying colored pigments, fluorescent pigments, infrared pigments and the like to each component of fibers with different combined rate.

[55] The composite fibers of side by side type, a constituent element of the present invention, may be produced by using a conventional well-known art, and two components are described with 'the first ingredient' and 'the second ingredient' to illustrate easily.

[56] Being schematically observed such composite fibers of side by side type at a side cross-section, the fiber is circular shape and area and form of its right and left side may be differently formed. Also, the first ingredient and the second ingredient corresponding to each component of left and right side are consisted of the same or combined different, respectably, and the said combination may be selected according to a property of a special pigment being mixed to fibers.

[57] It is preferable for a functional fiber of two components of the present invention to have a melting property since it is prepared by synthetic high molecules and a special pigment being mixed and dispersed and then melt-spinning. For such melt-spinning, thermoplastic synthetic high molecules is preferable which is molten by heating to high temperature and solidified by returning at low temperature, and it may include polyester, nylon, polypropylene, polyethylene, polyurethane and the like.

[58] And, in case of using a different one for the first ingredient and the second ingredient, it is preferable for melt-spinning to select those that have an excellent inter- solubility between the first ingredient and the second ingredient and an interfacial adhesive property.

[59] To render functionality to composite fibers of the present invention, it must be used to mix a general pigment and a special pigment. For such pigment, while colored pigments, fluorescent pigments, infrared pigments and the like can be without limitation, it is preferable to use those whose heat resistance is excellent up to extent not to change its property at melting point of selected synthetic high molecules for fibers.

[60] While it is not restrictive for colored pigment to render colors to composite fibers of the present invention, it may be preferable to use those whose heat resistance and blending property or compatibility to synthetic high molecules for fibers is excellent.

[61] As fluorescent pigments to render functionality to composite fibers of the present invention, a fluorescent material such as Kalcoseads, Kalcomins, Kalcozeans, Rhodamines and Lumogens may be used, and it is a pigment whose external appearance has color and which emit a fluorescence same with an external color.

[62] And, it is preferable to select and use a fluorescent material of metal oxide series such Sr(PO )C1: Eu(blue emitting), Zn GeO : Mn(green emitting), Y O S: Eu(red emitting) and the like, which emit various fluorescence and its external appearance is invisible color, e.g. white color.

[63] For an effect of preventing forgery which is main object of the present invention, fluorescent pigment may be illustrated in further details as folio wings; most of a fluorescent material generally has any colors or white color under visual light and displays a fluorescent property by being excited by 365nm, long wavelength under a commercially available ultraviolet ray lamp. But, several special fluorescent materials display a property that is excited only ultraviolet ray of long wavelength or only ultraviolet ray of short wavelength.

[64] For example, fluorescent materials which is excited at ultraviolet ray of long wavelength (365nm) may include trade name Lumiluχ^[CD-702(green color, 520nm) of Honeywell company and trade name D-034(off yellow colorr, 507nm), IPO-13(red color, 620nm), IPO-15(orange color, 590nm), IPO-19(blue color, 450nm) of DAYGLO's company, and a chemical composition is Y O S:Eu(red color), Zn GeO :Mn(green color), 3(Ba,Mg) Al O :Eu:Mn(green color) BaMg Al O :Eu(blue color). On the other hand, fluorescent materials which is excited at ultraviolet ray of short wavelength (254nm) may include, for example, trade name Lumilux CD-770(green color, 530nm) of Honeywell company and trade name IPO-18(green color, 530nm) of DAYGLO's company, and a chemical composition is Zn SiO :Mn(green color), CaY Tb AlO (green color, US 2006/0055307A1). Therefore, functionality can be maximized with a differential application of the said pigment to the first ingredient and the second ingredient of fibers.

[65] While it is not restrictive for infrared ray pigment to render functionality to composite fibers of the present invention, it may be preferable to use those whose heat resistance is excellent up to extent not to change its property at melting point of selected synthetic high molecules for fibers, and infrared ray absorbing agent such as imminiumes compound, diimminiumes compound, aminiumes compound, polymethines compound and phthalocyanine compound may be preferably used.

[66] The products of the said infrared ray pigment is, for example, epolight

1117(component: Tetrakisamminium, color: brown, maximum absorbing wavelength: 1071nm), epolight 3045 (component: Nickel dithiolene, color: black grey, maximum absorbing wavelength: 1097nm) of Epolin compony, USA, and IR-820(component: Ploymethine, color: green, maximum absorbing wavelength: 820nm) of Nippon chemical, Japan, which may be available with being mixed with high molecules for fibers and have an excellent heat resistance.

[67] The present invention can be achieved with obtainment of composite fibers of side by side type by mixing colored pigment, fluorescent pigment, infrared ray pigment and the like to synthetic high molecules of the first ingredient and the second ingredient and then melt-spinning, and functionality is variously displayed such as visual effect, fluorescent effect and infrared ray effect from a monofilament of one strand according to mixing condition.

[68] For example, if fibers are prepared by containing colored pigment to the first ingredient and containing invisible fluorescent pigment to the second ingredient, functional effect is expressed such that color by colored pigment is displayed under visual ray and color emitting light by fluorescent pigment is displayed under ultraviolet ray.

[69] As another example, if fibers are prepared by containing infrared ray pigment to the first ingredient and containing colored fluorescent pigment to the second ingredient, functional effect is expressed such that color by colored fluorescent pigment contained fibers is displayed under visual ray and color by colored fluorescent pigment is displayed under ultraviolet ray and black color by absorbing infrared ray is displayed under infrared ray.

[70] Such functional effect may be variously displayed according to parameter combining the first ingredient, the second ingredient and a special pigment constituting fibers. The following example is to illustrate the present invention more in detail, but to restrict the present invention to this example.

[71] [Example 1]

[72] The example relates to a manufacturing method that functional fiber display blue color under visual ray and red fluorescence under ultraviolet ray of long wavelength.

[73] To prepare composite fibers of side by side type, the first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Phthalocyanine Blue (CI. 74160) having blue color, colored pigment, to 95 % by weight of polyester (main component; polyethylene terephtahalate, melting point: 259⁰C) chip of synthetic high molecules and then by heating and mixing.

[74] And, the second ingredient is also prepared to a master batch for melt-spinning by adding 3 % by weight of fluorescent pigment (purchased from Wooksung Chemical company, Trade name; PANAX RED PKS-225, wavelength emitting light: 520nm) having white of external color and which displays red fluorescence under ultraviolet of short and long wavelength, to 97 % by weight of polyester (main component; polyethylene terephtahalate, melting point: 259⁰C) chip of synthetic high molecules and then by heating and mixing.

[75] The resultant master batch of the first ingredient and the second ingredient is charged into an extruder for spinning with the ratio of 50:50 by weight and then molten and spun such that a diameter of fibers is 30D (about 9 denier). The composite fibers of side by side type prepared from the said method is cut to 5D of length to make a monofilament, and then it is admixed to a procedure of manufacturing papers with a small amount.

[76] [Example 2]

[77] The example relates to a manufacturing method that functional fiber display blue color at a half side of fibers and yellow color at the other half side of fibers under visual ray.

[78] The first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Phthalocyanine Blue (CI. 74160) having blue color, colored pigment, to 95 % by weight of polyester (the same with Example 1) chip of synthetic high molecules and then by heating and mixing.

[79] The second ingredient is also prepared like the first ingredient to a master batch for melt-spinning by adding 7 % by weight of Disazo yellow (CI. 21096) having yellow color, colored pigment, to 93 % by weight of polyester chip of synthetic high molecules and then by heating and mixing.

[80] The other process is carried out by the same with Example 1.

[81] [Example 3]

[82] The example relates to a manufacturing method that functional fiber display red color under visual ray, red fluorescence under ultraviolet ray of long wavelength and green fluorescence under ultraviolet ray of short wavelength.

[83] The first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Rhodamine B (CI. Basic Violet 10) having red color, colored and fluorescent pigment, to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing.

[84] The second ingredient is also prepared like the first ingredient to a master batch for melt- spinning by adding 5 % by weight of fluorescent pigment (purchased from Honeywell company, Trade name; Lumiluxtϋ-770, wavelength emitting light: 520nm) having white of external color and which displays green fluorescence under ultraviolet of short wavelength, to 95 % by weight of polyamide chip and then by heating and mixing.

[85] The other process is carried out by the same with Example 1.

[86] [Example 4]

[87] The example relates to a manufacturing method that functional fiber display white color under visual ray, red color under ultraviolet ray of short wavelength and green fluorescence under ultraviolet ray of long wavelength.

[88] The first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of fluorescent pigment (purchased from DAYGLO's company, Trade name; IPO- 19, wavelength emitting light: 450nm) having white of external color and which displays blue fluorescence under ultraviolet of short wavelength, to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing.

[89] The second ingredient is prepared to a master batch for melt-spinning by adding 5

% by weight of fluorescent pigment (purchased from DAYGLO's company, Trade name; IPO- 18, wavelength emitting light: 530nm) having white of external color and which displays green fluorescence under ultraviolet of long wavelength, to 95 % by weight of polyester (the same with Example 1) chip and then by heating and mixing.

[90] The other process is carried out by the same with Example 1.

[91] [Example 5]

[92] The example relates to a manufacturing method that functional fiber display off white color under visual ray, red color under ultraviolet ray of long wavelength and black color under a region of infrared ray by absorbing infrared ray.

[93] The first ingredient is prepared to a master batch for melt-spinning by adding 3 % by weight of fluorescent pigment (purchased from Wooksung chemical company, Trade name; PANAX RED PKS-225, wavelength emitting light: 520nm) having white of external color and which displays red fluorescence under ultraviolet of long and short wavelength, to 97 % by weight of polyester (the same with Example 1) chip of synthetic high molecules and then by heating and mixing.

[94] The second ingredient is prepared to a master batch for melt-spinning by adding 5

% by weight of infrared ray pigment (purchased from Epolin company, Trade name; Epolight 1117, component: Tetrakisamminium, wavelength emitting light: 107 lnm) having brown of external color and which absorbs infrared ray at a region of near infrared ray, to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip and then by heating and mixing.

[95] The other process is carried out by the same with Example 1.

[96] [Example 6]

[97] The example relates to a manufacturing method that functional fiber display red color under visual ray and black color under a region of infrared ray by absorbing infrared ray.

[98] The first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Rhodamine B (CI. Basic Violet 10) having red color, colored and fluorescent pigment, to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing.

[99] The second ingredient is prepared to a master batch for melt-spinning by adding 5

% by weight of infrared ray pigment (purchased from Nippon gunpowder company, Trade name; IR-820, component: Polymethine, wavelength emitting light: 820nm) having green of external color and which absorbs infrared ray at a region of near infrared ray, to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing. [100] The other process is carried out by the same with Example 1.

[101] [Example 7]

[102] The example relates to a manufacturing method that functional fiber display blue color under visual ray, red color under ultraviolet ray of long wavelength and black color under a region of infrared ray by absorbing infrared ray.

[103] The first ingredient is prepared to a master batch for melt-spinning by adding 3 % by weight of fluorescent pigment (purchased from Wooksung chemical company, Trade name; PANAX RED PKS-225, wavelength emitting light: 520nm) having white of external color and which displays red fluorescence under ultraviolet of long and short wavelength, to 97 % by weight of polyester (the same with Example 1) chip of synthetic high molecules and then by heating and mixing.

[104] The second ingredient is prepared without addition anything to polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules.

[105] And, the said first ingredient and the second ingredient are mixed and molten-spun to prepare a monofilament, and dyeing process is further carried to dye a portion of Nylon. Dyeing process is carried out by using a known art. Dyeing solution is prepared by diluting 1Og of Acid blue AS(trade name: Indo, produced by Mohita dye chem. company), an acidic dye of blue color series, to 20Og of water and then adjusting pH 5 with formic acid. A monofilament is dipped into the resultant dyeing solution and heated at 8O⁰C during 30 minutes for pigmentation, and then washed with water and dried.

[106] The other process is carried out by the same with Example 1.

[107] Functionality and a visual effect of a functional fibers prepared by the said examples is shown the below table 1.

[108] Table 1

[109] The functional fiber for preventing forgery to achieve the other object of the present invention may be produced by preparing the composite fibers having a cross section of a side by side type by melting and spinning a master batch of at least two kinds obtained by mixing a functional pigment to resins which have different melting point each other, and then by heat treating at thermal deformable temperature of the said resins.

[110] At this time, thermal deformable temperature means measured temperature at when high molecules is deformed when rising temperature at a constant velocity while applying a constant load on high molecules.

[I l l] Next is a detailed description of the functional fibers being produced to the other object of the present invention.

[112] The composite fibers of side by side type, a constituent element of the present invention, may be produced by using a conventional well-known art, which may be produced by melting and spinning a master batch of two kinds or more being mixed a functional pigment to at least one resin whose dissolving temperature is different through one nozzle such that fibers has a cross section being attached with a side by side type. The fibers having a cross section of a side by side type produced with the said method take a deformation such as bowing or crooking and the like since resins are extended and contracted according to a physical property of resins including melting temperature and molecular weight when being heated to thermal deformable temperature of the said resins and cooled. Therefore, the present invention can provide fibers of particular form by using the said property.

[113] Being explained more concretely, in case of using resins of the same kind, fibers are produced by using the resins that have more high melting temperature as resins of the first master batch, and the resins that have more low melting temperature as resins of the second master batch, and the produced fibers turn a monofilament. The fibers are crooked toward a direction of component of the second master batch with heat treatment by difference of contraction and expansion.

[114] Also, the fibers produced by combining resins of different kind as the first master batch and the second master batch respectively are crooked by difference of contraction and expansion according to melting property of each high molecules.

[115] In the present invention, it is preferable for the said resins to have melting property.

It is preferable for the said resins to use at least one selected from polyester, nylon, polypropylene, polyethylene and polyurethane which are molten by heating at high temperature and solidified by returning to low temperature for the said melt-spinning. [116] Also, it is preferable for composite fibers to add a functional pigment to render a visual effect or a device detecting effect. At least one pigment selected from colored pigment, fluorescent pigment and infrared ray pigment may be used as the said functional pigment, and it emit a different color according to wavelength of a light. The content of a pigment is selected freely within the scope without side-effect to a spinning process since this fiber is not used with cloths or fabrics.

[117] Being explained more concretely, the said master batch is used with preparing the first master batch and the second master batch of two kinds whose melting temperature are different, thereby enabling to be prepared to fibers having two components. And the said the first master batch and the second master batch may be produced with the same or different resins. The said composite fibers may be produced to have a cross section of a side by side type by charging at least two master batch into each extruder for spinning and then molten and spun it through one nozzle.

[118] Namely, the section of composite fibers of a side by side type produced by using two kinds of master batch may be approximately any one form selected from a circle, a triangle, a quadrangle, an oval, and an area and a shape of its left and right side may be formed differently. Also, it can be produced by combining the first ingredient and the second ingredient corresponding to left and right ingredient identically, or differently.

[119] And, in case of using a different one for the first ingredient and the second ingredient, it is preferable for melt-spinning to select those that have an excellent inter- solubility between the first ingredient and the second ingredient and an interfacial adhesive property.

[120] Namely, the said first master batch and the said second master batch are charged into each extruder for spinning and then molten and spun it through one nozzle, thereby making it possible to produce to have a cross section of a side by side type.

[121] The functional fiber for preventing forgery is produced to have a special pattern by producing a monofilament with cut of the said composite fiber being molten and spun and then heat treating at thermal deformable temperature of the said resins, or by mix- spinning the said composite fiber to occur twisting at a constant length and heat treating at thermal deformable temperature of the said resins, and then cutting it to prepare with a monofilament.

[122] The said special pattern may be "C" type, "O" type or "S" type.

[123] Next is a detailed description of the method of manufacturing fibers of a particular form according to the present invention. The method of manufacturing the functional fibers for preventing forgery for the other object of the present invention may be consisted two embodiments according to a form of the produced fibers as folio wings, the first one comprises the steps of;

[124] a) preparing a master batch of at least two kinds by adding a functional pigment to resins which have different melting point each other;

[125] b) preparing composite fibers having a cross section of a side by side type by melt- spinning the said master batch of at least two kinds;

[126] c) making the said fibers to a monofilament by cutting with constant length;

[127] d) cooling after heat treatment at thermal deformable temperature of the said resins,

[128] and the monofilament produced by the said method may be produced to "C" type or

"O" type.

[129] The second embodiment comprises the steps of;

[130] a) preparing a master batch of at least two kinds by adding a functional pigment to resins which have different melting point each other;

[131] b) preparing composite fibers having a cross section of a side by side type by melt- spinning the said master batch of at least two kinds;

[132] c) forming a twist to be screwed by admixing and threading the said composite fibers and then making a twisted bundle;

[133] d) cooling after heat treatment at thermal deformable temperature of the said resins;

[134] e) making the said composite fibers formed a twist to a monofilament by cutting with constant length;

[135] and the monofilament produced by the said method may be produced to "S" type.

[136] More preferably, the said master batch is consisted with the first master batch and the second master batch of two kinds whose melting temperature are different, and the said the first master batch and the second master batch may be produced by using the same or different resins.

[137] The method of manufacturing a fiber having a special pattern according to the present invention may be achieved by producing a monofilament with cutting the composite fiber of side by side type being attached two components shortly and then heat treating at thermal deformable temperature of the first ingredient and the second ingredient, or by mix-spinning the said composite fiber to occur twisting at a constant length and heat treating, and then cutting it shortly to prepare with a monofilament and the like after deforming a special shape.

[138] The monofilament produced with such method may be produced with "C" type, "O" type or "S" type and the like unlike the conventional fiber pattern. It is preferable for the said monofilament to use after cutting it to a 3 ~ 15mm of length, but not restricted to that.

[139] It is also included within the scope of the present invention the articles for preventing forgery that are produced by mixing a monofilament of a special form according to the present invention combining with identical form or at least two forms to paper or sheet with a small amount.

[140] Namely, it is included within the scope of the present invention the paper having strips of many colors for preventing forgery that are produced by comprising a process preparing paper with admixing the said monofilament to a source of paper, and the articles for preventing forgery that are produced by mixing the said monofilament with a synthetic resin and then molding or extruding it.

[141] The fiber of such special pattern can represent various effects by combining the first master batch and the second master batch which are obtained by mixing resins constituted fibers and a functional pigment and then heat treating it, and the following is a detailed description of the present invention with the below example, but the example described below is not to limit any scope of the present invention.

[142] [Example 8]

[143] In the example 8, fibers of a special form are "C" type, and this example relates to a manufacturing method that functional fiber display blue color under visual ray and red fluorescence under ultraviolet ray of long wavelength.

[144] To prepare composite fibers of side by side type, the first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Phthalocyanine Blue (CI. 74160) having blue color, colored pigment, to polyester (polyethylene terephtahalate, melting point: 26O⁰C) chip of synthetic high molecules and then by heating and mixing.

[145] And, the second ingredient is also prepared to a master batch for melt-spinning by adding 3 % by weight of fluorescent pigment (purchased from Wooksung Chemical company, Trade name; PANAX RED PKS-225, wavelength emitting light: 520nm) having white of external color and which displays red fluorescence under ultraviolet of short and long wavelength, to polyester (polyethylene terephtahalate, melting point: 21O⁰C) chip of synthetic high molecules and then by heating and mixing.

[146] The resultant master batch of the first ingredient and the second ingredient is charged into an extruder for spinning with the ratio of 50:50 and then molten and spun such that a diameter of fibers is 30D (about 9 denier).

[147] And, the prepared composite fibers are cut to 5D of length. And it is charged into a heated chamber, heated to 13O⁰C, kept during 30 minutes, and then cooled a room temperature.

[148] [Example 9]

[149] In the example 9, fibers of a special form are "O" type, and this example relates to a manufacturing method that functional fiber display blue color at a half side of fibers and yellow color at the other half side of fibers under visual ray.

[150] The first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of fluorescent pigment (purchased from DAYGLO's company, Trade name; IPO- 19, wavelength emitting light: 450nm) having white of external color and which displays blue fluorescence under ultraviolet of short wavelength, to polyester (polyethylene terephtahalate, melting point: 21O⁰C) chip of synthetic high molecules and then by heating and mixing.

[151] The second ingredient is prepared to a master batch for melt-spinning by adding 5

% by weight of fluorescent pigment (purchased from DAYGLO's company, Trade name; IPO- 18, wavelength emitting light: 530nm) having white of external color and which displays green fluorescence under ultraviolet of long wavelength, to polyamide (Nylon 6, melting point: 215⁰C) chip of synthetic high molecules and then by heating and mixing.

[152] The resultant master batch of the first ingredient and the second ingredient is charged into an extruder for spinning with the ratio of 70:30 and then molten and spun such that a diameter of fibers is 30D (about 9 denier).

[153] And, the prepared composite fibers are cut to 5D of length. And it is charged into a heated chamber, heated to 15O⁰C, kept during 30 minutes, and then cooled a room temperature.

[154] [Example 10]

[155] In the example 10, fibers of a special form are "S" type, and this example relates to a manufacturing method that functional fiber display red color under visual ray, red fluorescence under ultraviolet ray of long wavelength and green fluorescence under ultraviolet ray of short wavelength.

[156] The first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Rhodamine B (CI. Basic Violet 10) having red color, colored and fluorescent pigment, to polyamide (Nylon 66, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing.

[157] The second ingredient is also prepared like the first ingredient to a master batch for melt- spinning by adding 5 % by weight of fluorescent pigment (purchased from Honeywell company, Trade name; Lumiluxtϋ-770, wavelength emitting light: 520nm) having white of external color and which displays green fluorescence under ultraviolet of short wavelength, to polyamide (Nylon 6, melting point: 215⁰C) chip and then by heating and mixing.

[158] The resultant master batch of the first ingredient and the second ingredient is charged into an extruder for spinning with the ratio of 60:40 and then molten and spun such that a diameter of fibers is 30D (about 9 denier).

[159] And, 30 strands of the composite fibers prepared by the said method become to one mixed tread, and are twisted to form a twist of four times per lcm. And it is charged into a chamber, heated to 15O⁰C, kept during 30 minutes, and then cooled a room temperature. And then it is cut to 5D of length and unstranded.

[160] [Example 11]

[161] In the example 11, fibers of a special form are "S" type of double strand, and this example relates to a manufacturing method that functional fiber display off white color under visual ray, red color under ultraviolet ray of long wavelength and black color under a region of infrared ray by absorbing infrared ray.

[162] The first ingredient is prepared to a master batch for melt-spinning by adding 3 % by weight of fluorescent pigment (purchased from Wooksung chemical company, Trade name; PANAX RED PKS-225, wavelength emitting light: 520nm) having white of external color and which displays red fluorescence under ultraviolet of long and short wavelength, to polyester (polyethylene terephtahalate, melting point: 26O⁰C) chip of synthetic high molecules and then by heating and mixing.

[163] The second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of infrared ray pigment (purchased from Epolin company, Trade name; Epolight 1117, component: Tetrakisamminium, wavelength emitting light: 107 lnm) having brown of external color and which absorbs infrared ray at a region of near infrared ray, to polyamide (Nylon 6, melting point: 215⁰C) chip of synthetic high molecules and then by heating and mixing.

[164] And, mixed tread consisted of 15 strands of the composite fibers prepared by the said method become to three mixed tread to intercross three strands, and are twisted to form a twist of six times per lcm. And it is charged into a chamber, heated to 15O⁰C, kept during 30 minutes, and then cooled a room temperature. And then it is cut to 5D of length and unstranded.

[165] Functionality and a visual effect of a functional fibers prepared by the examples is shown the below table 2. [166] Table 2

Industrial Applicability

[167] The monofilament of a side by side type produced by the said method may be used as various methods such as method of mixing when producing a paper, method of dispersing it into resins when producing a plastic sheet, method of attaching on a surface of particular products by dispersing it into a coating solution, and method of using as a functional thread by using a filament, and used as an element for identifying authenticity of particular product demanded security such as a bank bill, a passport, a check and wertpapier.

Claims

[1] A fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery is produced by heating and mixing the first ingredient and the second ingredient of a form of chip made of synthetic high molecules to melt-spine it and then introducing a special pigment with a dyeing method.

[2] A fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery is produced by preparing a master batch for melt-spinning which is produced by adding a special pigment to any one of the first ingredient and the second ingredient of a form of chip made of synthetic high molecules and then heating and mixing, and heating and mixing the said master batch with the other one ingredient to melt-spine it, and then introducing a special pigment with a dyeing method.

[3] A fiber for preventing forgery according to any one of claims 1 or 2, characterized in that the said synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers are selected from polyester, nylon, polypropylene, polyethylene and polyurethane which are enable to melt and spine.

[4] A fiber for preventing forgery according to any one of claims 1 or 2, characterized in that the said synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers use synthetic high molecules which the first ingredient and the second ingredient are same or different due to mixing property of a special pigment.

[5] A fiber for preventing forgery according to any one of claims 1 or 2, characterized in that the said special pigment being mixed to the synthetic high molecules of the first ingredient and the second ingredient consisting composite fibers is colored pigments, fluorescent pigments, infrared pigments and the like, and it is possible for a monofilament to have a various effect in visible ray, ultraviolet ray, infrared ray and the like by blending a special pigment differently to the synthetic high molecules of the first ingredient and the second ingredient.

[6] A fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery may be produced such that half side displays blue and the other half side displays yellow by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Phthalocyanine Blue (CI. 74160) having blue color, colored pigment, to 95 % by weight of polyester chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 7 % by weight of Disazoyellow (CI. 21096) having yellow color, colored pigment, to 93 % by weight of polyester chip of synthetic high molecules and then by heating and mixing.

[7] A fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery may be produced such that red color is displayed at visible ray, fluorescent red color is displayed at ultraviolet ray of long wavelength, and fluorescent green color is displayed at ultraviolet ray of short wavelength by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of Rhodamine B(CI. Basic Violet 10) having red color, colored and fluorescent pigment, to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent green color at ultraviolet ray of short wavelength to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing.

[8] A fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery may be produced such that white color is displayed at visible ray, red color is displayed at ultraviolet ray of short wavelength, and fluorescent green color is displayed at ultraviolet ray of long wavelength by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent blue color at ultraviolet ray of short wavelength to 95 % by weight of polyamide (Nylon 6, melting point: 25O⁰C) chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent green color at ultraviolet ray of long wavelength to 95 % by weight of polyester chip of synthetic high molecules and then by heating and mixing.

[9] A fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery may be produced such that off- white color is displayed at visible ray, red color is displayed at ultraviolet ray of long wavelength, and black color is displayed at a region of infrared ray by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt-spinning by adding 3 % by weight of fluorescent pigment whose appearance is white and which displays fluorescent red color at ultraviolet ray of short and long wavelength to 97 % by weight of polyester chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of infrared ray pigment whose appearance is brown and which absorbs infrared ray at region of near infrared ray to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing.

[10] A fiber for preventing forgery that a composite fiber of side by side type being attached two components is prepared to a monofilament and it is introduced at a procedure of preparing papers, wherein the said fiber for preventing forgery may be produced such that red color is displayed at visible ray, red color is displayed at ultraviolet ray, and black color is displayed at region of infrared ray by charging each master batch of the first ingredient and the second ingredient into an extruder for spinning with the ratio of 50:50 by weight and then melt-spinning such that a diameter of fibers is 30D (9 denier), wherein the said first ingredient is prepared to a master batch for melt- spinning by adding 5 % by weight of Rhodamine B having red color, colored and fluorescent pigment, to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing, and the said second ingredient is prepared to a master batch for melt-spinning by adding 5 % by weight of infrared ray pigment whose appearance is green and which absorbs infrared ray at region of near infrared ray to 95 % by weight of polyamide chip of synthetic high molecules and then by heating and mixing.

[11] A functional fiber for preventing forgery characterized in that it is produced by preparing the composite fibers having a cross section of a side by side type by melting and spinning a master batch of at least two kinds obtained by mixing a functional pigment to resins which have different melting point each other, and then by heat treating at thermal deformable temperature of the said resins.

[12] A fiber for preventing forgery according to claims 11, characterized in that the said functional pigment is at least one selected from colored pigments, fluorescent pigments, infrared pigments so that it express a different color according to wavelength of light.

[13] A fiber for preventing forgery according to claims 12, characterized in that the said resins be prepared by using at least one selected from polyester, nylon, polypropylene, polyethylene and polyurethane.

[14] A fiber for preventing forgery according to claims 13, characterized in that the said master batch is consisted of two kinds, the first master batch and the second master batch whose melting temperature is different, and the said first master batch and the said second master batch may be prepared by using the same resin or different resin.

[15] A fiber for preventing forgery according to claims 11, characterized in that the said composite fiber be produced such that it has a cross section of a side by side type by charging a master batch of two kinds or more into each extruder for spinning and by melting and spinning it through one nozzle.

[16] A fiber for preventing forgery according to claims 14, characterized in that the said first master batch and the said second master batch are charged into each extruder for spinning and then molten and spun it through one nozzle, to produce to have a cross section of a side by side type.

[17] A fiber for preventing forgery according to any one of claims 15 or 16, characterized in that the said functional fiber for preventing forgery have a special pattern by producing a monofilament with cut of the said composite fiber being molten and spun and then heat treating at thermal deformable temperature of the said resins, or by mix-spinning the said composite fiber to occur twisting at a constant length and heat treating at thermal deformable temperature of the said resins, and then cutting it to prepare with a monofilament.

[18] A fiber for preventing forgery according to claims 17, characterized in that the said special pattern is "C" type, "O" type or "S" type.