WO2001005907A1

WO2001005907A1 - Fluorescent composition, ink composition, and printed matter

Info

Publication number: WO2001005907A1
Application number: PCT/JP2000/004790
Authority: WO
Inventors: Noriaki Fukushima; Yoshinori Yamamoto; Hiroyuki Mitsuhashi; Yukinori Yamada; Tomohisa Nishimoto
Original assignee: Hitachi Maxell, Ltd.
Priority date: 1999-07-19
Filing date: 2000-07-17
Publication date: 2001-01-25
Also published as: AU5853900A

Abstract

A fluorescent composition with excellent light resistance comprising a base material and a particulate organic fluorescent dye which has a particle diameter of 10 to 2,000 nm and is excited by ultraviolet to emit a light in the visible region; and an ink composition comprising this fluorescent composition and a solvent. With this ink composition, a desired mark can be printed on an article without impairing its appearance. The printed mark can be detected with high sensitivity over long. Furthermore, this ink composition is safe for the human body, and there are no particular limitations on the environment in which the composition is used.

Description

Specification

Fluorescent composition, ink composition and printed matter

The present invention relates to an organic fluorescent dye that emits light having an emission center in the visible light region when excited by ultraviolet light, and in particular, a fluorescent composition containing an organic fluorescent dye that is substantially invisible or difficult to recognize in the visible light region, An ultraviolet-excited ink composition that contains an organic fluorescent dye and is used for printing with a marker pen, dot-impact pudding, stamp-type pudding, ink-jet pudding, etc., and printed matter created using the ink composition And about.

Background art

In recent years, information such as the manufacturer and product name of goods has been displayed as barcodes and certain characters and numerical values, etc., and read by optical detection methods such as barcode readers. It is widely used for distribution analysis. Recently, such barcodes and OCR systems are used not only for products, but also for file management. For example, systems that distribute items by code management, such as mail items, are used. It has been applied to the delivery of goods. In addition, banks and others have introduced a system that prints character and numerical information on forms and uses this information to sort and manage the information.

Bar code printing includes contact printing and non-contact printing. Among them, the contact printing method includes a method using a marker pen and a bar code writer, and the non-contact printing method includes an ink jet printing method. In particular, the ink jet printing method is a method in which an ink composition is injected onto a surface to be printed through a nozzle to perform printing.Since a non-contact printing method is used, a non-uniform shape surface, such as a plastic sheet. Suitable for printing on cardboard surfaces.

The ink compositions used in the ink jet printing method include (1) stable without long-term storage without phase separation or sedimentation, (2) passing without clogging nozzles, and (3) ink composition. Good adhesion to the printing surface; (4) the ink composition dries quickly on the printing surface; and (5) the printed matter after drying has excellent adhesion to the printing surface, and (6) weather resistance Sex and durability must be high. Also, Inkjets (7) The ink composition for ink jet printing needs to be charge-controlled so that printing can be controlled by the ink jet printer, which is a characteristic characteristic of the ink composition for ink jetting, which is not required for other ink compositions. Must have. By the way, bar code printing including such an ink jet printing method includes (a) a method of printing a bar code such as black on a white background, and (b) a method of being excited by ultraviolet rays of 300 to 400 nm. A method of printing an ink composition containing an organic fluorescent dye that emits blue, green or red visible light has been used or proposed.

In the method of printing a bar code such as black on a white background (a), the information is read using the difference in reflectance between the bar code and the base. However, there is a disadvantage that the appearance of the article is inevitably deteriorated because the reflectance in the visible light region is used. Further, even in a reading system using an OCR, character information may be printed in blue, black, or the like, which inevitably impairs the appearance of the article.

As a method for improving such barcodes such as black and white, a method (b) in which an ink using an organic fluorescent dye which emits visible light when excited by ultraviolet rays is used for a barcode has been proposed. Printed matter using such an organic fluorescent dye-based ink is practically invisible or difficult to recognize in the visible light region, and thus has the advantage of being able to print without impairing the appearance of the article, and is readable by a machine. At the same time, it has the advantage of being able to visually recognize the presence of print-types, etc., because the light-emitting area when irradiating ultraviolet light is in the visible light area, and is attracting attention as an alternative to black-and-white barcodes. However, in the method using the above-mentioned conventional ink composition, the organic fluorescent dye to be used is inherently easily decomposed, and has poor light resistance and poor weather resistance. There was a problem that it declined. That is, the above-mentioned conventional ink tends to remarkably decrease in luminous intensity when stored at high temperature and high humidity even if it shows high luminous intensity at the beginning of preparation. Therefore, in order to solve such a problem, various additives are added to the ink, or the above-mentioned organic fluorescent dye dissolved on the surface of inorganic particles such as silica or organic fine particles such as acryl is adsorbed. It has been proposed to improve weather resistance.

However, the method of using additives and particles as described above requires storage in the ink state. It was found that, although effective in improving the printability, when the printed material was printed using this ink on a substrate, the luminescence intensity was reduced only by leaving the printed material at room temperature. In other words, even if the printed matter shows a high luminous intensity immediately after printing, after long-term storage, luminescence cannot be confirmed even if irradiated with excitation light, or the luminous intensity is insufficient, making it impossible to read by a machine. It has been found. For this reason, the method using the above-mentioned organic fluorescent dye has a problem that the conditions of use are extremely limited.

In preparing the above ink, an organic fluorescent dye is usually dissolved in a ketone-based organic solvent such as methyl ethyl ketone / methyl isobutyl ketone. When such an ink is used, there is a problem that such a solvent invades the urethane or polyamide resin of the ink occluding body for occluding the ink, and significantly reduces the durability of the ink occluding body. In addition, when printing with a printer such as an ink jet printer, the use of the solvent is extremely harmful to the human body, making it extremely difficult to use it in offices. There was also a problem of receiving.

Disclosure of the invention

An object of the present invention is to print on a product without impairing the appearance of the product, and to detect the printed product with high sensitivity over a long period of time, and furthermore, without affecting the ink occlusion material, UV-excitable ink composition that is safe and does not impose any restrictions on the use environment, a fluorescent composition used for such an ink composition, and a dot-like, thin-film, or thick An object of the present invention is to provide a printed matter or a fluorescent composition printed in a film form.

The present invention, in order to achieve the above object,

A fluorescent composition comprising a base material and an organic fluorescent dye which emits light in the visible light region when excited by ultraviolet light, wherein the organic fluorescent dye is granular;

In an ink composition comprising a resin, an organic fluorescent dye which is excited by ultraviolet light and emits light in a visible light region, and a solvent, the organic fluorescent dye is in the form of particles having a particle size of 10 to 200 nm. An ink composition,

and

Contains an organic fluorescent dye that emits in the visible region when excited by ultraviolet light A printed material having a printed layer, wherein the organic fluorescent dye is in the form of particles having a particle size of 10 to 2,000 nm.

I will provide a.

BEST MODE FOR CARRYING OUT THE INVENTION

The organic fluorescent dye used in the present invention is a dye that emits light having an emission center in a visible light region (wavelength 400 to 700 nm) when excited by ultraviolet light (wavelength less than 400 nm). It is a dye that is substantially invisible or difficult to recognize. Although the emission color is not limited, those emitting red (wavelength: around 60 O nm, more preferably 6 15 ± 20 nm) visible light are particularly preferable because of their excellent detectability. Used.

This is because the use of inexpensive and readily available silicone photodiodes as photoelectric conversion elements for detecting visible visible light increases the visible light reception sensitivity at longer wavelengths than at shorter wavelengths. This is because sufficient detection sensitivity can be easily obtained with a dye that emits light. In addition, fluorescent whitening agents are added to commonly used white paper, and it may emit blue light when irradiated with ultraviolet light. When printed on white paper to which this fluorescent whitening agent has been added, organic fluorescent dyes that emit red light will not emit organic fluorescent light even if the fluorescent whitening agent added to the white paper emits light. Since it is far from the emission wavelength of the dye, the emission of the dye can be easily detected.

As described above, the organic fluorescent dye used in the present invention has no absorption in the visible light region, and therefore is invisible in the visible light region in a non-excited state, and is excited by ultraviolet light to have a long wavelength region near 600 nm. A red-emitting organic fluorescent dye having an emission center wavelength is preferably used. A typical example is a ligand having a rare-earth element such as europium or samarium as an emission center and having a large number of 7Γ electrons. And a metal complex in which is a counter ion.

Among them, a europium compound having a large light emission amount is most preferable. In particular,

It has no absorption in the visible light region of 400-700 nm, and is therefore substantially invisible in the visible light region, and has an emission center wavelength of 61.5 ± 20 nm when excited by ultraviolet light. Containing europium, which includes tenyl trifluoroacetone, naphthoyl trifluoroacetone, benzoyl trifluoroacetone, methylben Distribution of zyltrifluoroacetone, floyltrifluoroacetone, bivaloyltrifluoroacetone, hexafluoroacetylacetone, trifluoroacetylacetone, fluoroacetylacetone, heparofluorovyl, and nonylvivaroylm, etc. Examples of the metal complex include ligands, and among them, a europium compound having a ligand of tenoline trifluoroacetone, naphthoyl trifluoroacetone, or methylbenzoyl trifluoroacetone having a large emission amount is preferable.

Such organic fluorescent dyes are disclosed in Melby et al., J. Am. Chem. Soc., Vol. 186, Vol. 5, pp. 117, 1964. It can be synthesized by the method described in the gazette. Commercially available products of such organic fluorescent dyes include "Rumilux CD331", "Rumilux CD332", "Rumilux CD335", manufactured by Riedel Dehan, and Mitsui Chemicals, Inc. "ER-120" and "ER-122".

However, such organic fluorescent dyes are inferior in storage stability, such as light resistance and weather resistance, as described above, and are in an ink state, in a printed state or in a state of a printed fluorescent composition (hereinafter, simply referred to as “printed state”). The light emission intensity of the printed matter tends to decrease with time, and the storage stability of the printed matter is particularly poor. That is, in the ink state, the ink solvent intervenes between the dye and the outside air, thereby preventing direct contact between the dye and the outside air.However, in the printed state, there is no intervening substance such as the ink solvent, and the dye does not exist. The decomposability directly affects the stability of the printed matter. This phenomenon is the same when the dye is adsorbed on the surface of inorganic or organic particles.The dye is present on the surface of the particles in a molecular state as well as in a dissolved state in the ink solvent. Even in the case of printed matter using ink, deterioration due to decomposition cannot be suppressed because the dye comes into direct contact with the outside air. When the above ink is printed on paper, cloth, or the like, which is a printing material, a certain printing material has various functional groups on the surface, and the functional groups decompose the printed organic fluorescent dye. The light emission output tends to be remarkably reduced even when left at room temperature.

Accordingly, the present inventors have developed a method for reducing the influence of the organic fluorescent dye from the outside air and, when a printed material is obtained, reducing the effect of the functional group of the printed material to suppress the decomposability of the organic fluorescent dye. Various studies were made. As a result, by putting the organic fluorescent dye in the bulk state (granular state), not only the ink state but also the printed matter However, it has been found that the long-term storage stability is improved and a high luminous output can be maintained.In other words, in the present invention, when the above-mentioned organic fluorescent dye is used, it is combined with a base material, and preferably has a particle size of 10 to 2 , 00 O nm granular. By using such a granular material, excellent storage stability can be obtained not only in an ink state using a solvent but also in a printed matter or a luminescent composition.

The reason that such storage stability can be obtained by the present invention is considered as follows. When the organic fluorescent dye is formed into bulk particles having a particle size of 10 to 200 nm, the printed dye or fluorescent composition is prepared using the dye, and the dye comes into contact with the outside air or the functional group of the substrate. However, it is considered that only the surface of the particulate matter is deteriorated, and the active dye is still present inside, so that the decrease in the luminescence output is suppressed even after long-term storage. In addition, by adopting the shape of the above-mentioned granular material, compared to the case where a dissolved organic fluorescent dye is used as in the past, even when printing is performed on a printing material such as paper or cloth which easily absorbs ink, the inside of the printing material is As a result, the ink does not penetrate into the surface of the printing material, and the surface of the printing material is concealed.

The reason why the particle size in the above range is good is that a particle size of less than 1 O nm does not sufficiently improve the light stability of the print material and the effect of preservability such as weather resistance, and the dye easily penetrates into the print material. That's why. In addition, when it exceeds 2,000 nm, the dyes fall off from the printed matter, and depending on the viewing angle, the organic fluorescent dyes may be visible, which causes problems.

In addition, as a base material that carries a dye, there are an inorganic base material prepared by a sol-gel method or the like, and a resin base material. From the viewpoints of flexibility and adhesion to a printed material, a resin base material is preferable.

Dot-impact and stamp-type inks use a uniform solution of the ink composition in order to obtain clear printing and to prevent clogging of nozzles when printing with inkjet printing. Therefore, in the prior art, ketone solvents and the like have been used as solvents capable of dissolving the organic fluorescent dye. However, ketone-based solvents cannot convert organic fluorescent dyes into particulate matter in bulk, and the dyes dissolve and come into contact with the outside air in molecular form. In the state of printed matter or fluorescent composition, storage stability, that is, light resistance ゃ weather resistance deteriorates remarkably. In addition, such a solvent invades an ink occluding material that absorbs ink, that is, a cloth ribbon made of a polyamide resin in a dot impact pudding, and a foamed urethane in a stamp pudding, and significantly reduces the durability. . In addition, this solvent generates vapors harmful to the human body, and is restricted for use in offices and the like. Therefore, in one preferred embodiment of the present invention, a solvent containing 94% by weight or more of water or / and ethanol is used. However, from the viewpoint of environmental friendliness, 95% or more of water or / and ethanol is contained. Solvents are more preferably used. More preferably, it is water or / and ethanol only, most preferably water only. When another solvent is used in a proportion of 6% by weight or less, the other solvent is preferably one in which the organic fluorescent dye is insoluble, but even if it is slightly soluble, it is mixed with water or / and ethanol. Any combination of these can be used without any particular limitation as long as the organic fluorescent dye can be present as particulate matter in a bulk state.

When water and / or ethanol is used as a solvent, the base material is preferably a resin having low reactivity with an organic fluorescent dye and improving printability and durability of a printed layer, and is usually a resin soluble in the above solvent. However, a type of emulsifying and dispersing may be used in some cases. Specific examples of such resins include polyvinyl alcohol, phenolic resins, polyester resins, acrylic resins, cellulosic resins, polyamides, and maleic resins. Among them, polyvinyl alcohol which is dissolved in the above-mentioned solvent of the present invention and which has an excellent effect of dispersing the organic fluorescent dye is preferably used. The amount of the base resin used depends on the type thereof, but is usually 50 to 1000 parts by weight, preferably 100 to 100 parts by weight, based on 100 parts by weight of the organic fluorescent dye. 0 parts by weight, more preferably 200 to 300 parts by weight, particularly 500 to 2000 parts by weight.

In the case of using water and / or ethanol as solvent, tree fat as base material, even the oxygen permeability coefficient of ^{1 X 1 0- 1 9 (m} 2 · S- 1 · P a 1) less the following resin It is particularly preferred to contain one kind. . When such a low oxygen permeable resin is used, the organic fluorescent dye is covered with the resin, and the dye is effectively prevented from being oxidized and degraded by oxygen in the air in the print layer. it can. For antioxidants Usually, quinones are used.However, in the case of printed matter that is constantly exposed to the air, it is more effective to use the above-mentioned low oxygen permeable resin than the quinones to prevent the organic fluorescent dye from oxidizing. It is.

Oxygen permeability coefficient 1 X 10- ¹⁹ The ^{^{(m 2 - - S "1}} Pa" 1) The following resin, For example other, polyvinyl alcohol resins, polyvinyl alcohol resins (Biniruaru call one vinyl acetate copolymer, etc.) , A polyvinyl resin, a cellulose resin, a polyester resin, a polyester resin, a polyimide resin, a polyamide resin, and the like, and these are used alone or as a mixture of two or more. Considering the solubility in a solvent, the stability of the ink, the dispersibility of the organic fluorescent dye, and the like, a polyvinyl alcohol resin or a polyvinyl alcohol resin is most preferable. Since the oxygen permeability coefficient depends on the degree of saponification of the polyvinyl alcohol-based resin, a resin having a desired oxygen permeability coefficient can be easily obtained by adjusting the degree of saponification. Generally, the saponification degree of 0.2 or more polyvinyl alcohol resin, and at the same time the oxygen permeability coefficient is ^{^{IX 10- 19 (m 2 · S-}} 1 · Pa- 1) below, soluble in an aqueous solvent is very well It is desirable when applied to inkjet ink.

The oxygen permeability coefficient "in together with ⁽¹ following resins, the oxygen permeability coefficient of ^{^{1 X 10- 19 (m 2 ·}} S- 1 · Pa 1 X 10_ 19 m 2 · S- 1 · Pa)" 1) For example, polyvinyl resins such as polyvinyl butyral, polyvinyl pyrrolidone, and vinyl pyrrolidone monovinyl acetate copolymer may be used in combination. In addition, urethane resins containing a large amount of hydroxyl groups in the molecular chain and soluble in water and / or ethanol, and urethane resins such as acryl-urethane graft copolymers are also effective in improving the adhesion to pet films. Therefore, it is preferably used.

In the present invention, the amount of oxygen permeability coefficient ^{^{1 X 10- 19 (m 2 ·}} S- 1 · Pa -1) or less of the resin, based on the total weight of the ink composition, from 0.05 to 30 wt% Is preferably 0.5 to 20% by weight, more preferably 1 to 15% by weight. This range is preferred when less than 05% by weight reduces the oxygen permeation inhibitory effect, and when it exceeds 30% by weight, the viscosity of the ink becomes too high and nozzles are easily clogged. It is because it becomes.

In the present invention, the oxygen permeability coefficient of the resin is determined according to ASTM-D1434-75. (Measurement method of gas permeability coefficient in plastic films and sheets) can be measured and evaluated.

In another preferred embodiment of the present invention, as the solvent for the ink composition, a medium having a boiling point of 200 ° C. or higher and a medium in which the organic fluorescent dye is insoluble or has low solubility is used. This makes it possible to make the above pigment into bulk particulate matter with a particle size of 10 to 2, OO Onm, and there is no fear of generating harmful vapors to the human body, and it is used in offices and the like. This also makes it possible to prepare an ink composition that is not subject to any restrictions on the use environment.

Among the hardly volatile solvents having a boiling point of 200 ° C or more used in another preferred embodiment of the present invention, those having a boiling point of 250 ° C or more, which is more difficult to volatilize, are more preferable from the viewpoint of environmental friendliness. Examples of such media include higher fatty acids that are liquid at room temperature, such as oleic acid, linoleic acid, and linolenic acid, castor oil, liquid paraffin, machine oil, polyoxyethylene (POE), polyoxypropylene (POP), and alkyl ethers. POP alkyl ether, POE alkyl ether, polyethylene glycol, polypropylene glycol, glycerin, sorbic acid ester, benzyl alcohol and the like. As the other medium, those in which the organic fluorescent dye is insoluble are preferable, but even if the organic fluorescent dye is slightly soluble, the organic fluorescent dye is used in a bulk state in a combined system with a non-volatile medium having a boiling point of 200 ° C or higher. As long as it can be present as a granular material, it can be used without any particular limitation.

In another preferred embodiment of the present invention, as the base material resin, a resin having low reactivity with an organic fluorescent dye and improving printability and durability of a printed layer is preferable, and is usually soluble in the above-mentioned solvent. However, a type of emulsifying and dispersing in some cases may be used. Specific examples include a rosin resin, a phenol resin, a shellac resin, a ketone resin, an alkyd resin, a maleic resin, and a rosin-modified maleic resin. Among these, a rosin resin, a rosin-modified maleic resin, and the like, which dissolve in the above-mentioned solvent of the present invention and have an excellent effect of dispersing an organic fluorescent dye, are preferably used.

The amount of the base resin used depends on the type, but is usually 50 to: 100,000 parts by weight of L, preferably 100 to 100,000 parts by weight, per 100 parts by weight of the organic fluorescent dye. Preferably it is 200 to 3000 parts by weight, especially 500 to 2000 parts by weight. The reason why this range is preferable is that if it is less than the above lower limit, the adhesion strength of the printed layer is weak, and if it exceeds the above upper limit, the luminous intensity of the printed matter or the fluorescent composition becomes weak.

In the present invention, the organic fluorescent dye is added to the solvent together with the base resin, and the resulting mixture is well dispersed and mixed by a dispersing machine such as a ball mill or a sand mill. A uniform ink composition is obtained.

The amount of the organic fluorescent dye to be used is generally 0.01 to 30 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the solvent. This range is preferable because if the amount is less than 0.01 part by weight, the light emission intensity is low, and if the amount exceeds 30 parts by weight, the light emission intensity cannot be increased due to concentration quenching. The particle size of the organic fluorescent dye before dispersion is usually 10 to 50 zm. However, the organic fluorescent dye is pulverized at the same time as the dispersion so as to have a particle size of 10 to 2, O O Onm after dispersion. If the particle size after dispersion is less than 1 Onm, the dye will be close to the dissolved state, and deterioration will progress over time, making it difficult to maintain the luminescence output for a long time.If it exceeds 2,000 Onm, the dispersibility of the particulate matter Or dispersion stability deteriorates, sedimentation occurs, and it is difficult to print uniformly. For this reason, the lower limit of the particle size after dispersion is particularly preferably 50 nm or more, and more preferably 100 nm or more. The upper limit of the particle size after dispersion is preferably 80 Onm or less, more preferably 60 Onm or less, and even more preferably 500 nm or less.

The upper limit of the particle size of the dye that can stably maintain the dispersed state in the ink composition is mainly determined by the viscosity of the solvent, and 800 nm when a low-viscosity solvent such as water and / or ethanol is used. The following is preferred.

In the present invention, the organic fluorescent dye composed of such particulate matter may have a particle diameter after dispersion within the range of 10 to 2,000 nm, and all of the particulate matter has a uniform particle diameter. You don't need to be.

In the present specification, the particle diameter of the organic fluorescent dye refers to a sample prepared by diluting the ink composition about 1,000 times with a solvent having the same composition as the solvent contained in the ink composition, and preparing a cell having a diameter of 12 mm. The values were measured by dynamic light scattering at room temperature, using a 5mW He-Ne laser, at a measurement angle of 90 degrees and a total of 100 integrations. In order to improve the dispersibility of the organic fluorescent dye, the ink composition of the present invention may contain a surfactant together with the base resin. In order to further suppress the deterioration of the organic fluorescent dye, an appropriate amount of a phosphorus-based organic compound or the like can be used as an additive. Further, when used as an ink for ink-jet printing, an appropriate amount of a charge adjusting agent, a pH adjusting agent, and the like can be contained.

For example, it is possible to add L i salts such as L in0 _3, K salts such as KS CN, Hosuhoniumu salts represented by the following formula (1), and the like Anmoniumu salt as a charge control agent. Of these, phosphonium salts and ammonium salts are more preferable because of high dispersion stability of the ink composition. The addition amount of these charge control agents is preferably from 0.05 to 5% by weight, more preferably from 0.1 to 5% by weight, based on the total weight of the ink composition. . This addition amount is preferred because the charge control effect becomes insufficient when the content is less than 0.05% by weight, and the effect is saturated when the content exceeds 5% by weight.

"Ri" ten

R ₂ — A— R ₃ X "(1) I

Wherein A is a nitrogen atom or a phosphorus atom, and R to R ₄ are the same or different and are each a hydrogen atom or a linear or cyclic hydrocarbon group having 1 to 14 carbon atoms. 1 ^ to 11 ₄ at least two of but it may also be bonded to each other to form a ring.)

When printing on plastic sheets, bags, bottles, etc., it is desirable to add 0.05 to 0.5% by weight of a fluorinated surfactant. As described above, when the fluorine-based surfactant is added, the dot diameter is reduced to about 40% as compared with the case where no fluorine-based surfactant is added. The above-mentioned addition amount range is preferable because the effect of reducing the dot diameter is small when the content is less than 0.05% by weight, and the ink composition tends to foam when the content is more than 0.5% by weight.

In the present invention, using such an ink composition, the ink composition can be used for dot-impact printing, stamp printing, ink-jet printing, stamping, and other forms of mail such as forms and postcards. Printed on the surface of various goods Then, a printing layer made of a desired mark such as a bar code is formed to obtain a printed material. At that time, since the ink composition contains the above-mentioned solvent, it is safe for the human body, is not restricted in the use environment, and can be safely operated even in an office with insufficient ventilation.

In the printed matter thus produced, the organic fluorescent dye in the printed layer does not have a light-emitting and light-absorbing component in the visible light region, and therefore has no risk of impairing the appearance of the article as a printed layer that is invisible or difficult to recognize. In addition, when the printed matter is irradiated with ultraviolet light, the dye in the print layer is excited and emits light in the visible light region, which can be visually recognized, and a reading reader such as a silicone photodiode as a photoelectric conversion element. , Desired mark information can be read with high sensitivity. Further, the most significant feature of the present invention is that the above-mentioned organic fluorescent dye exists as fine particles in an ink state and a printed layer state, and has excellent storage stability, that is, excellent light resistance and weather resistance. Therefore, the mark information can be detected with high sensitivity over a long period of time.

Example

Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited only to the following examples. Hereinafter, “parts” means “parts by weight”.

Example 1

In 90 parts of water, 5 parts of polyvinyl alcohol (PVA made by Kuraray Co., Ltd.) is dissolved as a base resin, and it is practically invisible or difficult to recognize in the visible light range, and emits light when excited by ultraviolet rays. 0.5 parts of a dye to be dyed (trade name: “CD335” manufactured by Riedel de Haan, excitation wavelength: 365 nm, emission wavelength: 615 nm), dispersed by a planetary ball mill for 4 hours, An ultraviolet-excited ink composition containing the dye as a particulate having a particle size of 210 to 410 nm was prepared.

Example 2

In the same manner as in Example 1 except that the dispersion treatment time by a planetary ball mill was set to 8 hours, an ultraviolet-excited ink composition containing a pigment as particulate matter having a particle size of 120 to 23 O nm was prepared. did. Comparative Example 1

In 90 parts of methyl ethyl ketone, 0.5 part of the same dye as used in Example 1 was dissolved, and an acrylic resin ("Dianal BR-1" manufactured by Mitsubishi Rayon Co., Ltd.) was further used as a base resin. 0 6 ”) 9.5 parts were added, mixed well with stirring, and dissolved to prepare an ultraviolet-excited ink composition.

Comparative Example 2

0.5 parts of the same dye used in Example 1 was dissolved in 3 parts of methyl ethyl ketone. Next, this dye solution was mixed with 77 parts of water, 10 parts of silica particles having an average particle diameter of 10 O nm as inorganic particles, and 9.5 parts of polyvinyl alcohol (Kuraray PVA) as a base material resin. The resulting slurry was blended and mixed well with stirring to prepare an ultraviolet-excited ink composition.

When the ink compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were allowed to stand for 24 hours, the ink compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were all organic fluorescent dyes. No sedimentation was observed. From these results, each of the ink compositions of Examples 1 and 2 and Comparative Examples 1 and 2 can be used as a marker pen and ink for inkjet.

Next, with respect to each of the ink compositions of Examples 1 and 2 and Comparative Examples 1 and 2 which can be used as described above, the ink state and the fluorescence emission intensity when the printed matter was obtained were measured by the following methods. These results were as shown in Table 1.

The fluorescence emission intensity of the ink composition at the initial stage and after storage at high temperature (after storage in a high-temperature bath at 60 ° C for 400 days) was measured using a fluorescence spectrophotometer (“FP750” manufactured by JASCO Corporation). However, the values are shown as relative values with the initial light emission intensity of Example 1 being 100%.

Fluorescence intensity of printed matter>

The ink composition was filled in a marker pen and used to form a print layer on white paper. The fluorescence intensity of this printed matter, initially and after storage in a room for three months, was measured with a fluorescence spectrophotometer (“FP750” manufactured by JASCO Corporation). The relative values are shown as 0%. PT JP00

14 Table 1

As is evident from the results in Table 1 above, both ink compositions of Examples 1 and 2 have the initial fluorescent emission intensity increased because the organic fluorescent dye is present as particulate matter in a bulk state. In addition, the decrease in strength after high-temperature storage is suppressed, and the printed matter printed using this is also less reduced in strength after long-term storage. It can be seen that the storage stability is remarkably excellent even in the state where it was used.

In contrast, the ink composition of Comparative Example 1 had a low initial fluorescence emission intensity because the organic fluorescent dye was completely dissolved in the solvent, and the intensity deteriorated after high-temperature storage. In the state of a printed material, the strength is further reduced, and the deterioration after long-term storage is remarkable. In addition, the ink composition of Comparative Example 2 had a certain effect of improving the fluorescence emission intensity as compared with Comparative Example 1 by adsorbing the organic fluorescent dye on the surface of the inorganic particles. Compared with those of the printed matter, the printed matter is remarkably inferior, and particularly the printed matter has remarkably poor long-term storage characteristics.

Example 3

Water 9 0 parts, oxygen permeability coefficient was dissolved polyvinyl alcohol (manufactured by Kuraray Co., Ltd. P VA) 5 parts of ^{5 X 1 0 2 ° (m} 2. S- 1. P a 1), in which an organic fluorescent As a dye, Riederdehan product name "CD335" (excitation wavelength: 365 nm, emission wavelength: 615 nm, ligand: tenyl trifluoroacetone) 0.5 part was added. A dispersion treatment was performed for 4 hours using a planetary ball mill to prepare an ultraviolet-excited ink composition containing the above-described pigment as particulate matter having a particle size of 210 to 41 O nm. In the ink composition, the organic fluorescent dye was 0.52% by weight, the resin (polyvinyl alcohol) was 5.24% by weight, and the solvent (water only) was 94.24% by weight. Was. Example 4

Oxygen permeability coefficient in place of the ^{^{5 X 10- 2 ° (m 2}} · S -1 · P a- polyvinyl alcohol (manufactured by Kuraray Co., Ltd. PVA) 5 parts, the oxygen permeability coefficient is ^{^{7 X 10- 22 (m 2.}} S — Except for using 5 parts of polyvinyl alcohol (Kuraray PVA) of ¹ · Pa " ¹ ), the organic dye was included as a granular material having a particle size of 210 to 410 nm in the same manner as in Example 3. An ultraviolet-excited ink composition was prepared.

Example 5

Oxygen permeability coefficient "instead of ^{^{^{20 (m 2 · S- 1 ·}}} Pa- polyvinyl alcohol (manufactured by Kuraray Co., Ltd. PVA) 5 parts, the oxygen permeability coefficient is ^{^{3 X 10- 23 (m 2 -}} S" 5 X 10 1 · Pa ^"1 polyvinyl alcohol) (except using Kuraray Co., Ltd. PVA) 5 parts, the same procedure as in example 3, ultraviolet excitation organic fluorescent dye is included as granules having a particle size of two hundred and ten to four hundred and ten nm A mold ink composition was prepared.

Example 6

An ultraviolet-excited ink composition containing an organic fluorescent dye as a particulate having a particle size of 150 to 25 Onm was prepared in the same manner as in Example 3 except that the dispersion treatment time by a planetary ball mill was changed to 8 hours.

Example Ί

An ultraviolet-excited ink composition containing an organic fluorescent dye as granules having a particle size of 80 to 19 Onm was prepared in the same manner as in Example 3 except that the dispersion treatment time by a planetary ball mill was changed to 16 hours.

Example 8

Instead of the polyvinyl alcohol (manufactured by Kuraray Co., Ltd. PVA) 5 parts of oxygen permeability coefficient ^{^{5 X 10- 2 ° (m 2}} · S- 1 · Pa- 1), the oxygen permeability coefficient 4 X 10- ²⁰ (m ^2. S one ^¹ - Pa ^'1) except for using polyoxyethylene 5 parts, the same procedure as in example 3, ultraviolet excitation ink composition organic fluorescent dye is included as a particulate with a particle size 210-41 onm Was prepared.

Example 9

An ultraviolet-excited ink composition was prepared in the same manner as in Example 3, except that 0.1 part of "Fluorad FC430" manufactured by Sliem was added as a fluorinated surfactant. Was.

Reference example 1

Oxygen permeability coefficient of ^{^{5 X 10_ 2 ° (m 2}} · S- 1 · P a - 1) of the polyvinyl alcohol in place of (Kuraray Co., Ltd. PVA) 5 parts, the oxygen permeability coefficient is 3 X 10- ¹⁹ (m ² · except using polyvinyl acetate (UCC Co.) 5 parts of S one ¹ · Pa ^-1), and ethanol was used 9 0 parts, the same procedure as in example 3, the organic fluorescent dye particle size 210 to An ultraviolet-excited ink composition contained as 410 nm granules was prepared.

Reference example 2

Instead of 5 parts of polyvinyl alcohol (PVA manufactured by Kuraray Co., Ltd.) having an oxygen permeability coefficient of 5 xl O— ² ° (m ² 'S—i'Pa ^-1 ), an acrylic urethane graft copolymer [Taiseika Kogyo Co., Ltd. Ltd. "3DR- 057", solid content 35 wt%, the oxygen permeability coefficient ^{^{3 x 10- 18 (m 2 ·}} S- 1 · Pa "1) was repeated except for using 15 parts, the same procedure as in example 3 An ultraviolet-excited ink composition containing an organic fluorescent dye as particles having a particle size of 90 to 80 L was prepared.

Reference example 3

In the same manner as in Example 3 except that the dispersion treatment time by a planetary ball mill was set to 1 hour, an ultraviolet-excited ink composition containing an organic fluorescent dye as particles having a particle size of 900 to 1,40 Onm was prepared. did.

Comparative Example 3

In 90 parts of methyl ethyl ketone, 0.5 part of the same organic fluorescent dye as in Example 3 was dissolved, and this was mixed with an acryl-based resin (“Dyanal BR-106” manufactured by Mitsubishi Rayon, with an oxygen transmission coefficient of 9X). 10 " ¹⁹ (m ² · S- ¹ · Pa- ¹ )] 9.5 parts were added, mixed well by stirring and dissolved to prepare an ultraviolet-excitation ink composition.

Comparative Example 4

0.5 parts of the same organic fluorescent dye as in Example 3 was dissolved in 3 parts of methyl ethyl ketone. The dye solution, the average particle diameter 100 nm of silica force grain child 10 parts as inorganic particles 77 parts of water and oxygen permeability coefficient of 5 X 10- ² ° of ^{^{(m 2 · S- 1 · P}} a "1) Polyvinyl alcohol (PVA manufactured by Kuraray Co., Ltd.) was mixed in a slurry obtained by mixing 9.5 parts and mixed well by stirring to prepare an ultraviolet-excitation ink composition. When the ink compositions of Examples 3 to 9, Reference Examples 1 to 3 and Comparative Examples 3 and 4 were allowed to stand for one day and night, Examples 3 to 9, Reference Examples 1 and 2, and Comparative Examples 3 and 4 No sedimentation of the organic fluorescent dye was observed in each of the ink compositions described above, but sedimentation of the organic fluorescent dye was clearly observed in the ink composition of Reference Example 3. From these results, each of the ink compositions of Examples 3 to 9, Reference Examples 1 and 2, and Comparative Examples 3 and 4 can be used as a marker pen. It cannot be used for However, this evaluation is for applications requiring low-viscosity ink, such as a carpenter, and even with the particle size of Reference Example 3, use it at a high viscosity as in Examples 10 to 12. Since the pigment does not settle in the application, it can be used in applications such as Examples 10 to 12.

Next, for each of the ink compositions of Examples 3 to 9, Reference Examples 1 and 2 and Comparative Examples 3 and 4 which could be used as described above, the state of ink and the fluorescence when the printed matter was obtained were obtained in the same manner as described above. The emission intensity was measured. However, the fluorescence emission intensity of the printed matter was measured initially, after storage for 3 months indoors, and after storage for 1 month outdoors, and expressed as a relative value with the initial emission intensity of Example 3 being 100%. If the fluorescence emission intensity of the printed matter after storage outdoors for one month is 30% or more, it can be read with a barcode reader. Table 2 shows the results.

Table 2

As is clear from the results in Table 2 above, each of the ink compositions of Examples 3 to 9 and Reference Examples 1 and 2 was characterized in that the organic fluorescent dye having a particle size of 10 to 80 nm was a particulate material in a bulk state. As a result, the initial fluorescence emission intensity is high, and the decrease in the intensity after storage at high temperatures is small. In addition, the printed matter printed using this has a fluorescence emission intensity after storage at room temperature at a practical level (30% or more), and can be read by a barcode reader. Furthermore, indicia oxygen permeability coefficient was used each Inku composition ^{1 X 1 0- 1 9 (m} 2 · S- 1 · P example a containing at least one of the following resins 3-9 Surimono The results show that the ink composition of the present invention maintains light emission and weather resistance not only in an ink state but also in a printed state, and under the harsh conditions of an outdoor environment. It turns out that the property is high.

In contrast, the ink composition of Comparative Example 3 has a low initial fluorescence emission intensity because the organic fluorescent dye is completely dissolved in the solvent, and the intensity is further deteriorated after high-temperature storage. In the state of a printed material, the strength is further reduced, and the deterioration after long-term storage is remarkable. In addition, the ink composition of Comparative Example 4 had a certain effect of improving the fluorescence emission intensity compared to Comparative Example 3 by adsorbing the organic fluorescent dye on the surface of the inorganic particles. Compared with those of the printed matter, the printed matter is remarkably inferior, and particularly the printed matter has remarkably poor long-term storage characteristics.

Next, using the ink compositions of Example 5 and Reference Example 1 above, The following heat treatment test was performed to evaluate the preservability indoors and outdoors after heat treatment of the printed matter printed by the above method. That is, both ink compositions are applied on a glass plate and dried, and then dried at 60 ° C for 5 minutes (heat treatment A), at 100 ° C for 5 minutes (heat treatment B) or at 150 ° C. Heat treatment was performed for 5 minutes at C (heat treatment C), and the fluorescence emission intensity of the printed matter after the heat treatment was measured by the following method. Table 3 shows these results together with the crystallinity of the resin in the print layer after each heat treatment.

Fluorescence intensity of printed matter>

The fluorescence emission intensity of the printed matter after heat treatment was initially measured after storage for 6 months indoors and after storage for 3 months outdoors using a fluorescence spectrophotometer (“FP750” manufactured by JASCO Corporation). It is shown as a relative value with the initial light emission intensity of Example 5 being 100%.

Table 3

As is evident from the results in Table 3 above, the printed matter of Example 5 in which the crystallinity of the resin was 0.1 or more by the heat treatment was stored under severe storage conditions of 6 months at room temperature and 3 months at outdoor storage. However, compared with the printed matter of Reference Example 1 in which the crystallinity after the heat treatment was less than 0.1, the decrease in the emission intensity was considerably suppressed, and it was found that the light resistance and weather resistance were further increased.

Next, for each of the ink compositions of Examples 3 and 9, ink droplets were dropped on a white pet film, and the dot diameter and adhesion were evaluated. Table 4 shows the results. As for the dot diameter, when the dot diameter of the ink composition of Example 3 was 100, the dot diameter was indicated by a relative value. As is evident from the results in Table 4, in Example 9 in which the fluorinated surfactant was contained, Examples in which the fluorinated surfactant was not contained were used.

It can be seen that the dot diameter is smaller than that of 3. Table 4

Example 10

To 50 parts of castor oil and 40 parts of sorbic acid alkyl ester (Nippon Oil & Fats Co., Ltd. 0P-80) (both boiling point: 200 ° C or more), 10 parts of rosin ester resin (Arakawa Chemical Ester Gum AAL) as a binder The mixture was then heated and dissolved to produce a vehicle. In addition, a dye that is substantially invisible or difficult to recognize in the visible light region and emits light when excited by ultraviolet rays (trade name “CD335” manufactured by Rieder de Haan, Inc., excitation wavelength: 365 nm, emission wavelength: 615 nm), and the mixture was dispersed for 4 hours using a planetary ball mill to prepare an ultraviolet-excited ink composition containing the above-mentioned dye as particles having a particle size of 210 to 410 nm.

Example 1 1

An ultraviolet-excited ink composition containing a pigment as particulate matter having a particle size of 120 to 23 Onm was prepared in the same manner as in Example 10 except that the dispersion treatment time by a planetary ball mill was changed to 8 hours.

Example 12

An ultraviolet-excited ink composition containing a pigment as particulate matter having a particle diameter of 1000 to 160 Onm was prepared in the same manner as in Example 10 except that the dispersion treatment time by a planetary ball mill was changed to 1 hour.

Comparative Example 5

In 90 parts of methyl ethyl ketone (boiling point 80 ° C), 1.0 part of the same pigment used in Example 10 was dissolved, and an acrylic resin (trade name “Dyana” manufactured by Mitsubishi Rayon) was further used as a binder. One part BR-106 ”) was added, and the mixture was dissolved with good stirring and mixing to prepare an ultraviolet-excitation ink composition.

Comparative Example 6

An ultraviolet-excited ink composition was prepared in the same manner as in Example 10, except that the dispersion treatment time by a planetary ball mill was 0.5 hour. Measured by dynamic light scattering method The particle size of the dye thus obtained was 2,200 to 2,900 nm.

Comparative Example 9

In 5 parts of methyl ethyl ketone, 1.0 part of the same dye as used in Example 10 was dissolved. Next, castor oil (boiling point: 200 ° C or higher) 77 Rosin ester resin (ester gum AAL manufactured by Arakawa Chemical Co., Ltd.) was used as a binder in 7.7 parts. By adding and mixing 10 parts of 0 O nm silica particles, a silica dispersion slurry was obtained. The previously prepared dye solution was mixed with the slurry, and the mixture was stirred and mixed well to prepare an ultraviolet-excitation ink composition.

When the respective ink compositions of Examples 10 to 12 and Comparative Examples 5 to 7 were allowed to stand for one month, the ink compositions of Examples 10 to 12 and Comparative Examples 5 and 7 were: No sedimentation of the organic fluorescent dye was observed, but sedimentation of the organic fluorescent dye was clearly observed in the ink composition of Comparative Example 6. Further, the ink compositions of Examples 10 to 12 and Comparative Examples 5 to 7 were filled in urethane sponges having continuous pores and used as a stamp ink. The ink of Comparative Example 6 was urea of the ink occluding body. Invaded the sponge in the evening, making printing impossible. In addition, in the ink of Comparative Example 6, a lot of print blurring was observed, which is considered to be caused by sedimentation of the pigment.

Next, for each of the ink compositions of Examples 10 to 12 and Comparative Examples 5 to 7, the fluorescence emission intensity in the ink state was measured by the same method as described above, and the fluorescence emission intensity when a printed material was obtained. Was measured by the following method. In each case, the fluorescence emission intensity was shown as a relative value with the initial emission intensity of Example 10 being 100%.

Table 5 shows the results.

Each ink composition was used as a stamping ink and used to form a print layer on white paper. The fluorescence intensity of this printed matter initially and after storage in a room for three months was measured with a fluorescence spectrophotometer (“FP750” manufactured by JASCO Corporation), and the initial light emission intensity of Example 10 was measured. The relative values are shown as 100%. Table 5

Notes: 1) Prints were not possible due to the penetration of urethane in the ink storage.

2) There were many missing and blurred prints, and measurement was impossible. As is evident from the results in Table 5 above, the ink compositions of Examples 10 to 12 had the initial fluorescent emission intensity increased because the organic fluorescent dye was present as particulate matter in a bulk state. In addition, the decrease in the strength after high-temperature storage is suppressed, and the printed matter printed using the same is less reduced in the strength after long-term storage. It shows that the storage stability is remarkably excellent even in the state.

On the other hand, the ink composition of Comparative Example 6 has a low initial fluorescence emission intensity because the organic fluorescent dye is completely dissolved in the solvent, and the intensity is more deteriorated after storage at a high temperature. Remarkable. Furthermore, although the ink composition of Comparative Example 8 caused the organic fluorescent dye to be adsorbed on the surface of the inorganic particles, the ink composition of Comparative Example 6 exhibited a certain effect of improving the fluorescence emission intensity as compared with Comparative Example 6, but the present invention Compared with those of the printed matter, the printed matter is remarkably inferior, and the printed matter has remarkably poor long-term storage characteristics.

As described above, in the present invention, an organic fluorescent dye that is substantially invisible or difficult to recognize in the visible light region and emits light in the visible light region when excited by ultraviolet light is used as bulk particles. The presence of the mark allows the desired mark to be printed on the article without damaging its appearance, and allows the printed mark to be detected with high sensitivity over a long period of time, and is safe for the human body. It is possible to provide an ultraviolet-excitation type fluorescent composition, an ink composition, and a printed material thereof, which are not subject to any restrictions on the use environment.

Claims

The scope of the claims

1. A fluorescent composition comprising a base material and an organic fluorescent dye that emits light in the visible light region when excited by ultraviolet light, wherein the organic fluorescent dye is granular.

2. The phosphor composition according to claim 1, wherein the base material comprises a resin.

3. The fluorescent composition according to claim 1, wherein the organic fluorescent dye is substantially invisible in a visible light region.

4. The fluorescent composition according to any one of claims 1 to 3, wherein the particle size of the particulate organic fluorescent dye is 10 to 2, O O Onm.

5. The fluorescent composition according to claim 1, wherein the organic fluorescent dye is a europium compound having europium as a luminescent center.

6. The resin matrix ^{^{is, 1 X 10- 19 (m 2}} · S- 1 · fluorescent composition according to any one of claims 1 to 5 contains at least one resin having Pa or less oxygen permeability coefficient.

7. The fluorescent composition according to claim 1, wherein the content of the organic fluorescent dye is 0.1% by weight to 50% by weight based on the total weight of the composition.

8. In an ink composition comprising a resin, an organic fluorescent dye that emits light in the visible light region when excited by ultraviolet light, and a solvent, the organic fluorescent dye is in the form of particles having a particle size of 10 to 2,000 nm. An ink composition, comprising:

9. The ink composition according to claim 8, wherein the particle size of the organic fluorescent dye is 10 to 800 nm.

10. The ink composition according to claim 8, wherein the organic fluorescent dye is substantially invisible in a visible light region.

1 1. The ink composition according to any one of claims 8 to 10, wherein the organic fluorescent dye comprises a europium compound having europium as a luminescent center.

12. The ink composition according to any one of claims 8 to 11, wherein the organic fluorescent dye is not substantially dissolved in the solvent.

13. The ink composition according to any one of claims 9 to 12, wherein the solvent is water and / or ethanol.

14. The solvent according to any one of claims 8 to 12, wherein the solvent is a solvent having a boiling point of 200 ° C or more. The ink composition as described in the above.

15. A printed matter having a printing layer containing an organic fluorescent dye that emits in the visible light region when excited by ultraviolet light on an article, characterized in that the organic fluorescent dye is in the form of particles having a particle size of 10 to 2,000 nm. Printed matter.

16. The printed matter according to claim 15, wherein the organic fluorescent dye is substantially invisible in a visible light region.

17. The printed matter according to claim 15, wherein the organic fluorescent dye is a europium compound having europium as a luminescent center.

18. printed matter, 1 X 10- ¹⁹ (printed material c according to one of m ² · S- ¹ · Pa claims 15 to 17 contains at least one resin to have the following oxygen permeation coefficient

19. The printed matter according to any one of claims 15 to 18, wherein the content of the organic fluorescent dye is 0.1% by weight to 50% by weight.

INTERNATIONAL SEARCH REPORT International application No.

PCT / JP00 / 04790

A. CLASSIFICATION OF SUBJECT MATTER

Int. CI ⁷ C09K11 / 06, C09D11 / 02

According to International Patent Classification (IPC) or to both national classification and IPC

B. FIELDS SEARCHED

Minimum documentation searched (classification system followed by classification symbols)

Int .CI ⁷ C09 11/06, C09D11 / 02

Documentation searched other than minimum documentation to the extent that such documents are included in the fields searched

Electronic data base consulted during the international search (name of data base and, where practicable, search terms used)

C. DOCUMENTS CONSIDERED TO BE RELEVANT

Category * Citation of document, with indication, where appropriate, of the relevant passages Relevant to claim No.

X WO97 / l0307, Al (VIDEOJET SYSTEMS INTERNATIONAL INC.) .-19

20 March, 1997 (20.03.97)

Sc EP, 850281, Al & US, 5837042, A

& JP, 11-510213

JP, 8-239610, A (Mikuni Shikiso K.K.), .-19 17 September, 1996 (17.09.96),

Claims; Par. No. [0010], Par. No. [0014] (Family: none)

Y JP, 10-17571, A (Toyo Ink Manufacturing Co. Ltd.), 19

20 January, 1998 (20.01.98),

Claims (Family: none)

I 1 Further documents are listed in the continuation of Box C. [I See patent family annex.

* Special categories oi cited documents: "V later document published after the international filing date or

"A" document defining the general state of the art which is not priority date and not in conflict with the application but cited to considered to be of particular relevance understand the principle or theory underlying the invention "E" earlier document but published on or after the international filing "X" document of particular relevance; the claimed invention cannot be date considered novel or cannot be considered to involve an inventive

"L" document which may throw doubts on priority claim (s) or which i: step when the document is taken alone

cited to establish the publication date of another citation or other "Y" document of particular relevance; the claimed invention cannot be special reason (as specified) considered to involve an inventive step when the document is

"O" document referring to an oral disclosure, use, exhibition or other combined with one or more other such documents, such

means combination being obvious to a person skilled in the art

"P" document published prior to the international filing date but later "&, 'document member of the same patent family

than the priority date claimed

Date of the actual completion of the international search Date of mailing of the international search report

13 October, 2000 (13.10.00) 24 October, 2000 (24.10.00)

Name and mailing address of the ISA / Authorized officer

Japanese Patent Office

Facsimile No. Telephone No.

Form PCT / ISA / 210 (second sheet) (July 1992)