JP4895086B2 - Concealing scratch layer forming ink, concealing scratch printed matter and method for producing the same - Google Patents

Description

  The present invention relates to an ink used for forming a concealing scratch layer in a concealing scratch print, a concealing scratch print formed using the ink, and a method for producing the same.

  The concealing scratch printed matter is one in which confidential information data is printed on a predetermined area of the printing substrate, and a concealing scratch layer is provided on the confidential information via a release layer. In addition, it is used as a means for concealing the display section for ID information and passwords in the medium used for distributing ID information and passwords, as a means for concealing the answers in the medium used for answering quizzes and questions, etc. It is used as a printed matter for confirming confidential information formed under a peeling layer by a user rubbing and peeling the concealing scratch layer with a coin or a nail.

  In the concealing scratch card, the concealing scratch layer is required to have so-called "adhesion" that should not be easily peeled off due to rubbing between printed materials in the distribution stage, impact in the handling of printed materials, friction, etc. It can be easily scratched with coins and nails, etc., and if the swarf residue becomes a fine powder, there is a problem that it gets in between the nails and the surroundings are contaminated, so the swarf does not scatter finely and becomes a constant lump. Is requested.

  Conventionally, as a concealing scratch layer forming ink, a concealing scratch layer is formed by a solvent-type ink obtained by kneading a synthetic rubber resin such as SBR or NBR and a pigment such as aluminum powder using an organic solvent. It is known that it can be easily peeled off, etc., but it is easily peeled off when it comes in contact with adhesive tape, and it is vulnerable to rubbing due to contact between scratched prints, and confidential information data appears before use There is. In addition, when using organic solvents in the production of concealed scratch prints, it is generally necessary to meet standards such as the Fire Service Act and the Industrial Safety and Health Act (hereinafter referred to as the Labor Safety Act). Installation of such facilities is obligatory, and the burden on manufacturing is large. In recent years, there has been an increase in awareness regarding environmental issues, such as regulations on volatile organic substances (hereinafter referred to as VOC regulations), ascertaining emissions of specified chemical substances into the environment, and promotion of management improvements (hereinafter referred to as PRTR law). As a result of the development of laws and regulations, etc., it is required to consider the solvent used when producing scratch prints.

In addition, water-based emulsion inks have been proposed as the ink for forming the concealing scratch layer, which does not require expensive facilities and management systems that comply with various laws and regulations, and can reduce the burden on environmental conservation. In addition, there is known a hygienic scratch concealing ink with little odor (Patent Document 1). However, because of water-based ink, the drying property of the ink is slow at room temperature, which causes problems in production.
JP 2002-187388

  The present invention provides a concealing property in which the adhesion of the concealing scratch layer and the peelability of the concealing scratch layer are excellent and the physical properties (hereinafter referred to as “scratch property”) that make the scraped residue agglomerate instead of being powdery. It is an object of the present invention to provide a scratch layer forming ink, a concealing scratch printed matter, and a production method capable of easily producing the concealing scratch printed matter.

The ink for forming a concealing scratch layer of the present invention contains at least an active energy ray-curable resin composed of urethane (meth) acrylate and monofunctional (meth) acrylate, and contains a concealing pigment in a proportion of 3 to 30% by mass. characterized in that it.

  The monofunctional (meth) acrylate is a linear or branched alkyl ester having 8 to 23 carbon atoms of (meth) acrylic acid.

The concealing scratch printed matter of the present invention is a concealing scratch printed matter comprising at least an information layer on a printing substrate, a release layer above the information layer, and a concealing scratch layer formed on the surface of the release layer. A concealing scratch layer forming ink in which the scratch layer contains an active energy ray-curable resin composed of at least urethane (meth) acrylate and monofunctional (meth) acrylate and contains a concealing pigment in a proportion of 3 to 30% by mass. It is formed by these.

The method for producing a concealing scratch printed material of the present invention includes at least an information layer in a printing substrate on which an information layer is formed,
(1) A step of printing a release layer forming ink containing an active energy ray-curable resin by flexographic printing or a screen printing machine, and irradiating an active energy ray to form a release layer;
(2) A concealing scratch containing an active energy ray-curable resin composed of at least urethane (meth) acrylate and monofunctional (meth) acrylate on the surface of the release layer and containing a concealing pigment in a proportion of 3 to 30% by mass. It is characterized in that the layer forming ink is printed by a flexographic printing or a screen printing machine, and the steps of forming an obscuring scratch layer by irradiating active energy rays are sequentially performed.

  The concealable scratch layer forming ink of the present invention is composed of an active energy ray-curable resin composed of at least urethane (meth) acrylate and monofunctional (meth) acrylate, without using an organic solvent or water as a solvent. Because it forms a concealing scratch layer, it does not require expensive facilities and management systems that comply with various laws and regulations, has a low environmental burden, and does not require drying equipment. The concealing scratch layer can be easily formed with a high yield.

  Further, the concealing scratch printed matter of the present invention forms the concealing scratch layer using the above-described concealing scratch layer forming ink, and the concealing scratch layer itself has adhesiveness. In addition to excellent adhesion to the material, it can be scratched smoothly, and the scrap can be made into a scrap with a constant lump diameter.

  Further, the method for producing the concealing scratch printed matter of the present invention is to form the release layer and the concealing scratch layer by using an active energy ray-curable resin ink that does not contain an organic solvent, and therefore the same production process. The concealable scratch printed material can be easily produced.

  The basic configuration of the concealing scratch print of the present invention will be described with reference to FIG. FIG. 1 shows a basic configuration of the concealed scratch print of the present invention. In the figure, 1 is a printing substrate, 2 is an information layer, 3 is a release layer, and 4 is a concealing scratch layer.

  As the printing substrate 1, paper such as high-quality paper and coated paper, synthetic paper, polyester film, polyamide film, polyvinyl chloride film, polycarbonate film, polystyrene film, polypropylene film, polyethylene film, polyacrylic film, etc. Is mentioned.

  The information layer 2 is a confidential information data layer, which may be provided by printing using an active energy ray-curable resin ink, or by printing variable confidential information data using an inkjet printer using an inkjet ink. It may be formed.

  The release layer 3 is preferably formed using a solvent-type release layer forming ink or a release layer forming ink containing an active energy ray-curable resin.

  Examples of the solvent-type release layer forming ink include polyurethane acrylic resin, polyamide resin, and nitrocellulose resin, which are inks in which 5% by mass or less of a wax such as silicon or polyethylene wax is added as an additive. The release layer may be formed by applying the entire surface or a partial coating by a printing method or a flexographic printing method using an Aronix roller.

  Examples of the release layer forming ink containing an active energy ray-curable resin include (A) epoxy acrylate, (B) monofunctional (meth) acrylate and / or polyfunctional (meth) acrylate, and (C) styrene acrylic resin. And (D) a solventless release layer forming ink comprising silicone acrylate and / or silicone oil and a photopolymerization initiator. Hereinafter, (meth) acrylate means both acrylate and methacrylate.

  Component (A) is a bisphenol type, novolak type, alicyclic epoxy acrylate having an acryloyl group obtained by esterifying an epoxy group of an epoxy resin with acrylic acid, and has a weight average molecular weight of 400 to 1,000. Illustratively, bisphenol A type epoxy acrylate having a weight average molecular weight of 400 to 1,000 is preferable.

  Examples of the monofunctional (meth) acrylate in the component (B) include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, methoxyethyl (meth) acrylate, stearyl carbitol ( (Meth) acrylate, glycidyl (meth) acrylate, allyl (meth) acrylate, isooctyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, or Examples thereof include dimethylaminoethyl (meth) acrylate.

  Examples of the polyfunctional (meth) acrylate include 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and ethylene oxide. Modified bisphenol A di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol tetra (meth) acrylate, or tripropylene Examples include glycol di (meth) acrylate, and ethylene oxide-modified bisphenol A di (meth) acrylate is preferable.

  Component (C) is a copolymer of styrene with at least one of (meth) acrylic acid, (meth) acrylic acid ester, (meth) acrylamide derivative, preferably methyl acrylate, dimethylaminoethyl acrylate, A copolymer of styrene and at least one selected from 2-ethylhexyl acrylate, preferably having a weight average molecular weight of 10,000 to 30,000.

  The silicone oil as component (D) is contained for the purpose of release, and examples thereof include modified silicone oils such as dimethyl silicone oil, methylphenyl silicone oil, methyl hydrogen silicone oil, and fluorine-modified silicone oil.

  Examples of the silicone acrylate include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropylethoxysilane, γ-methacryloxypropyltrihydroxysilane, etc. And those having an acrylic structure. Moreover, the silicone acrylate which hardens | cures with an ultraviolet-ray with the silicone which has an acryloyl group, for example, the silicon acrylate which has 6-8 acryloyl groups per molecule is illustrated.

  Examples of the photopolymerization initiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, 4-phenylbenzophenone, 2,2-dimethoxy-1 , 2-diphenylethanone, benzyldimethyl ketal, 1-hydroxy-cyclohexyl phenyl ketone, 2-hydroxy-2-dimethoxy-1-phenylpropan-1-one, etc., preferably 4-methylbenzophenone, 4-phenyl Benzophenone derivatives such as benzophenone and 2,4,6-trimethylbenzophenone.

In order to obtain a release layer forming ink, the content of the component (A) is 1 to 20% by mass, preferably 5 to 10% by mass, and the content of the component (B) is 50 to 90% by mass, preferably 60 to 60%. 80% by mass, content of component (C) is 1-20% by mass, preferably 5-10% by mass, component (D) is 0.1-10% by mass, preferably 0.1-5% by mass, light Mixing may be performed so that the content of the polymerization initiator is 2 to 10% by mass, preferably 4 to 8% by mass. In the above composition, the case where ultraviolet rays are used as the active energy ray is exemplified, but when an electron beam is used, a photopolymerization initiator is unnecessary. In addition, the ultraviolet irradiation condition for the release layer forming ink layer is 1 to 1000 mJ / cm ² , preferably 10 to 500 mJ / cm ² .

  When the content of the component (D) in the release layer forming ink exceeds 10% by mass, the adhesion of the concealing scratch layer formed on the resulting release layer is lowered, and the scratch printed matter can be stored for a long time. During the handling, the concealing scratch layer is peeled off or is easily scratched, and the confidential information data printed on the lower side of the peeling layer cannot be retained. On the other hand, when the content of the component (D) is less than 0.1% by mass, the adhesion of the concealing scratch layer formed on the release layer is too strong, and the scratch layer is peeled off with a coin or a nail. When the confidential information data printed under the layer is disclosed, smooth scratch release is not obtained. Moreover, when using the silicon acrylate which has 6-8 acryloyl groups per molecule as (D) component, it may be 0.1-10 mass%, Preferably it may be 0.1-5 mass%, The numerical value The reason for limiting the range is the same as described above. The release layer is preferably formed using an ink containing an active energy ray-curable resin, and can be formed using the same manufacturing equipment as the concealing scratch layer forming step described later, which is preferable in production.

  As a film thickness of the peeling layer 3, it is 0.1-200 micrometers, Preferably it is 0.5-100 micrometers.

  Next, the concealable scratch layer forming ink will be described. The ink for forming a concealing scratch layer is composed of an active energy ray-curable resin containing urethane (meth) acrylate and monofunctional (meth) acrylate and a concealing pigment, and can form a concealing scratch layer having adhesiveness. is there.

  Urethane (meth) acrylate is obtained by reacting three kinds of a diol component, a polyisocyanate component, and a hydroxy group-containing (meth) acrylate compound.

  As the diol component, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, 1,4-butanediol, polybutylene glycol, 1,6-hexane Diol, neopentyl glycol, cyclohexanedimethanol, hydrogenated bisphenol A, polycaprolactone, trimethylolethane, trimethylolpropane, polytrimethylolpropane, pentaerythritol, polypentaerythritol, sorbitol, mannitol, arabitol, xylitol, galactitol, glycerin , Polyglycerin, polytetramethylene glycol, etc. Polyether polyol having at least one structure of polyethylene oxide, polypropylene oxide, ethylene oxide / propylene oxide block or random copolymerization, the polyhydric alcohol or polyether polyol and maleic anhydride, maleic acid, fumaric acid Examples thereof include polyester polyols that are condensates with polybasic acids such as itaconic anhydride, itaconic acid, adipic acid, and isophthalic acid, and caprolactone-modified polyols such as caprolactone-modified polytetramethylene polyol. As the diol component, polyolefin-based polyols and hydrogenated products thereof are preferable, and 1,2-polybutadiene diol, 1,4-polybutadiene diol, or hydrogenated products thereof are particularly preferable.

  Examples of the polyisocyanate component include aromatic, aliphatic and alicyclic polyisocyanates, among which tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, modified diphenylmethane diisocyanate, hydrogenated xylylene diene. Examples thereof include diisocyanates such as isocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, and 1,3-bis (isocyanatomethyl) cyclohexane.

  As the hydroxyl group-containing (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethylacryloyl phosphate, 4-butylhydroxy (meth) Acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3acryloyloxypropyl (meth) acrylate, caprolactone modified 2-hydroxyethyl (meth) acrylate, pentaerythritol tri (meth) acrylate , Dipentaerythritol penta (meth) acrylate, caprolactone-modified 2-hydroxyethyl (meth) acrylate, and the like.

  In the reaction, the diol and the polyisocyanate are reacted at a reaction molar ratio of k: k + 1 (molar ratio) (k is an integer of 1 or more), and further, a hydroxyl group-containing (metathesis) with respect to an unreacted isocyanate group in the reaction product. ) The acrylate is preferably reacted at a reaction molar ratio of 1: 2. In the reaction, it is preferable to use a catalyst such as dibutyltin dilaurate.

  Monofunctional (meth) acrylates include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, methoxyethyl (meth) acrylate, stearyl carbitol (meth) acrylate, glycidyl ( (Meth) acrylate, allyl (meth) acrylate, isooctyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, or dimethylaminoethyl (meth) An acrylate etc. are mentioned. Preferably, it is a C8-23 linear or branched alkyl ester of (meth) acrylic acid.

  Examples of the linear or branched alkyl ester having 8 to 23 carbon atoms of (meth) acrylic acid include isostearyl (meth) acrylate, lauryl (meth) acrylate, and the like. More preferably, these are mixtures and concealment. As an adhesive scratch layer, it can have a smooth scratch property while maintaining adhesion to the release layer.

  The content of the monofunctional (meth) acrylate in the active energy ray-curable resin is 20 to 80% by mass, preferably 30 to 60% by mass. When the content of monofunctional (meth) acrylate is less than 20% by mass, there is a problem that the film becomes too soft, and when it is more than 80% by mass, there is a problem that the film tends to be brittle.

  As the photopolymerization initiator, a benzophenone photopolymerization initiator and a phosphine oxide photopolymerization initiator may be mixed and used. Examples of the benzophenone photopolymerization initiator include benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, 4-methylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, 3 , 3′-dimethyl-4-methoxybenzophenone, [4- (methylphenylthio) phenyl] phenylmethanone, 2,4,6-trimethylbenzophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one Or a combination of two or more thereof.

  As the phosphine oxide photopolymerization initiator, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,6-dimethoxybenzoyl)- 2,4,4-trimethyl-pentylphosphine oxide, bis (2,6-dichlorobenzoyl) -phenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis ( 2,6-dichlorobenzoyl) -4-n-propylphenylphosphine oxide or the like is added alone or in combination.

  The total blending amount of the benzophenone photopolymerization initiator and the phosphine oxide photopolymerization initiator is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the active energy ray curable resin. If the total blending amount is less than 0.1 part by weight, it becomes difficult to complete the polymerization sufficiently, the monomer remains in the resulting concealing scratch layer, and the odor of the monomer remains. On the other hand, when the amount is more than 10 parts by mass, a dispersion odor of the initiator is generated or the molecular weight of the produced polymer is lowered, which is not preferable. Moreover, it is benzophenone type photoinitiator: phosphine oxide type photoinitiator (mass ratio) = 1: 10-10: 1.

  Furthermore, triethanolamine, triisopropanolamine, 4,4′-dimethylaminobenzophenone (Michler ketone), 4,4′-diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, 4-dimethylamino as an auxiliary for the photopolymerization initiator Ethyl benzoate, ethyl 4-dimethylaminobenzoate (n-butoxy), isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, 2,4-diisopropylthio Xanthone and the like can also be used in combination.

  Next, the concealment pigment is not particularly limited as long as it is a pigment that can conceal the information layer (confidential information data layer), but preferably at least one selected from carbon black, aluminum powder, vapor-deposited aluminum powder, and aluminum paste is used. Can be mentioned. The aluminum paste is a paste formed from a fine aluminum powder surface-treated with a fatty acid or the like using a hydrocarbon solvent such as mineral spirit or alcohol having a high boiling point.

The content of the active energy ray-curable resin in the concealing scratch layer forming ink is 10 to 90% by mass, preferably 40 to 60% by mass, and the content of the concealing pigment is 3 to 30% by mass, preferably Is preferably 5 to 25% by mass. If the ratio of the masking pigment to the active energy ray-curable resin is too large, the adhesion of the masking scratch layer to the release layer will be reduced, and the masking scratch layer will peel off due to scratches or scouring during long-term storage or handling. However, there is a risk that confidential information data will be exposed. On the other hand, when the blending ratio of the pigment is too small, the concealing property is lowered, and when the concealing scratch layer is shaved with a coin or the like, the peelability is lowered and the shaving becomes difficult. The irradiation condition of the ultraviolet rays for the ink layer for forming the concealing scratch layer is 1 to 1000 mJ / cm ² , preferably 10 to 500 mJ / cm ² . In the above composition, the case where ultraviolet rays are used as the active energy ray is exemplified, but when an electron beam is used, a photopolymerization initiator is unnecessary.

  The concealing scratch layer may be a single layer, but in order to ensure concealment, a multilayer structure of two or more layers made of the same material, a so-called “silver concealment layer” containing a black concealment layer and an aluminum paste, etc. It is good also as two or more layers of these. The concealing scratch layer has a thickness of 1 to 500 μm, preferably 1 to 300 μm, from the viewpoint of concealing properties and scratch properties.

  Moreover, as long as the concealing scratch printed matter of the present invention does not affect the adhesion and scratching property of the concealing scratch layer, functional layers 11 to 19 can be appropriately provided as shown in FIG. In the figure, 11 is a chromatic printing layer, 12 is an anchor layer, 13 is a protective layer, 14 is a white hiding layer, 15 is a pattern printing layer, 16 is an overcoat layer (OP layer), 17 is a one-point fluorescent printing layer, Reference numeral 18 denotes a character printing layer on the back side of the card, and 19 denotes a fluorescent printing layer. The same reference numerals as those in FIG.

  In FIG. 2, the chroma print layer 11 is a fine fine line pattern such as a forgery-preventing chroma pattern, and the anchor layer 12 is a chroma print layer 11 (forgery prevention) printed on a printing substrate. It is an object of the present invention to prevent UV deterioration of the printing layer) and to improve the adhesion between the information layer (variable confidential information data layer) printed on the anchor layer 12. In addition, the protective layer 13 aims to obtain good adhesion between the function of protecting the information layer (variable confidential information data layer) and the release layer provided on the protective layer. Further, the white hiding layer 14 forms a white hiding layer having good adhesion and leveling on the hiding scratch layer, the printability of the ink for the pattern printing layer 15 printed on the white hiding layer, and the printed matter. It is provided for the purpose of improving the appearance. Further, a pattern printing layer 15, an overcoat layer (OP layer) 16 for the purpose of protecting the pattern printing layer, and a fluorescent printing layer 17 for the purpose of preventing forgery may be provided. Moreover, you may provide the character printed layer 18 and the fluorescent printed layer 19 in the back surface of the base material 1 for the purpose of forgery prevention.

  In the scratch printed matter of the present invention, each of the release layer 3, the white hiding layer 14, the pattern printing layer 15, the OP layer 16, the fluorescent printing layer 17, the character printing layer 18, and the fluorescent printing layer 19 is made of an active energy ray curable resin. The same manufacturing process can be used, it is excellent in manufacturability, it does not require expensive equipment and management system complying with various laws and regulations, and it can reduce the burden on environmental conservation. In addition, it can be a hygienic scratch print with little odor.

  Examples of the printing means for each layer in the scratch printed material of the present invention include offset printing, flexographic printing, letterpress printing, silk screen printing, and gravure printing. When printing the release layer and the concealing scratch layer, screen printing, flexographic printing is possible. Printing is preferred. Screen printing has an advantage that thick printing can be easily performed. In addition, flexographic printing uses a “flexo printing machine” that attaches ink to convex portions of a photosensitive resin plate via an anilox roll and transfers it to a printing substrate, and has the advantage that it is not significantly affected by ink viscosity. .

As a manufacturing method of the concealable scratch print of the present invention,
(1) On the surface of the printing substrate 1, if necessary, a chromatic printing layer 11, an anchor layer 12, an information layer 2, and a protective layer 13 are sequentially formed, and then an active energy ray curable resin is formed on the protective layer 13. The release layer 3 is formed by irradiating an active energy ray with the release layer forming ink.
(2) Next, the masking scratch layer 4 is formed on the surface of the release layer 3 by irradiating the active energy ray with the masking scratch layer ink, and if necessary, the white masking layer 14 and the pattern printing. The layer 15, the OP layer 16, and the fluorescent printing layer 17 are preferably formed.

  In the method for producing a scratch printed material of the present invention, both the release layer 3 and the concealing scratch layer 4 are formed of an active energy ray-curable ink, so that the drying equipment and the Explosion-proof equipment can be dispensed with, and since it can be formed in the same manufacturing process, it has the advantage of excellent manufacturability.

  Next, the present invention will be described more specifically with reference to examples and comparative examples. The composition of the release layer forming ink and the concealing scratch layer forming ink used in the examples is as follows. “Parts” and “%” are based on mass.

(1) Release layer forming ink An ink for forming the release layer 3 was prepared by uniformly mixing and dispersing the following components.
・ Bisphenol A type epoxy acrylate (weight average molecular weight 500)
··· 10.0 parts · Ethylene oxide modified bisphenol A diacrylate · · 72.0 parts · Copolymerized styrene-dimethylaminoethyl methacrylate (weight average molecular weight 15,000) · · 10.0 parts · 6 to 6 per molecule Silicone acrylate having 8 acryloyl groups
1.0 parts Photopolymerization initiator (benzophenone derivative) 6.0 parts Polyethylene wax 1.0 part.

(2) Concealing scratch layer forming ink ・ Urethane acrylate with polybutadiene skeleton ¹⁾・ ・ 50 parts ・ Lauryl acrylate ・ ・ 45 parts ・ Isostearyl acrylate ・ ・ 5 parts ・ 2,4,6-trimethylbenzoyldiphenylphosphine oxide
・ ・ 4 parts ・ Methyl o-benzoylbenzoate ・ ・ 1 part ・ Aluminum paste (aluminum pure 60%, aluminum powder average particle size 15 μm, 40% is MFG solvent) ・ ・ 45 parts.

¹⁾ By reaction of 38 g (0.22 mol) of tolylene diisocyanate, 462 g (0.19 mol) of 1,2-hydrogenated polybutadiene diol having an average molecular weight of about 2400 and 7.8 g (0.06 mol) of hydroxypropyl acrylate The resulting urethane acrylate.

Example 1
After a chromatic pattern printing layer, an anchor layer, an information layer, and a protective layer are sequentially formed on the surface of the high-quality paper, the release layer forming ink obtained above is printed on the protective layer by flexographic printing, and the irradiation integrated light quantity is 30 mJ / cm ^2. Then, an ultraviolet ray was irradiated to form a release layer having a thickness of 3 μm.

Next, the surface of the release layer is flexographically printed with the ink for the concealing scratch layer obtained above, and irradiated with ultraviolet rays with an integrated irradiation light amount of 30 mJ / cm ² to contain a concealing scratch layer having a film thickness of 5 μm (containing the concealing pigment). After that, the white concealing layer, the pattern printing layer, the OP layer, and the fluorescent printing layer were sequentially formed. On the back surface of the printing substrate, a character printing layer and a fluorescent printing layer were formed to obtain a scratch card of the present invention.

(Example 2)
In place of the ink for forming the opacity scratch layer in Example 1, the scratch card was prepared in the same manner as in Example 1 except that the ink having a opacity pigment content in the opacity scratch layer of 25% by mass was used. Obtained.

(Comparative Example 1)
A scratch card was prepared in the same manner as in Example 1 except that the ink for forming the masking pigment in the masking scratch layer was used in place of the masking ink for forming the masking scratch layer 4 in Example 1. Got.

(Comparative Example 2)
A scratch card was prepared in the same manner as in Example 1 except that the ink for forming the masking pigment in the masking scratch layer was used in place of the masking ink for forming the masking scratch layer 4 in Example 1. Got.

(Comparative Example 3)
Implementation was performed except that the following concealing scratch layer forming ink was used in place of the concealing scratch layer forming ink in Example 1 and the concealing scratch layer (the content of the concealing pigment was 18% by mass) was used. A scratch card was obtained in the same manner as in Example 1.

(Concealing scratch layer forming ink)
・ Ethylene oxide modified trimethylolpropane triacrylate ・ ・ 34 parts ・ Trimethylolpropane triacrylate ・ ・ 13 parts ・ Multifunctional polyester acrylate (oligomer) ・ ・ 8 parts ・ Bisphenol A type epoxy acrylate (weight average molecular weight 500)
16 parts Hydroxycyclohexyl phenyl ketone 2 parts 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one 5 parts Aluminum paste (60% pure aluminum) Aluminum powder average particle size 15μm, 40% is MFG solvent) ・ ・ 34 parts ・ Polyethylene wax ・ ・ 2 parts.

  The scratch properties of the printed scratches obtained in Examples 1 and 2 and Comparative Examples 1 to 3 and the adhesion to the release layer were evaluated by the following methods.

(Scratch property)
The scratch printed material was rubbed with a coin, and the scratch property was evaluated by the following evaluation method.
○: Smoothly scratched, and the size of the lump of scrap was observed with an optical microscope, and most of the lump was 2 to 4 mm in size.
X: Most of the shavings have a particle size of about 20 to 200 μm and are in the form of fine powder.

(Adhesion with release layer)
A commercially available adhesive tape was rubbed and adhered to the surface of the scratch printed material with a finger, and was peeled off at an angle of 45 degrees after the contact, and the adhesion of the concealing scratch layer to the release layer was evaluated by the following evaluation method.
○: Adhesion with the release layer is good.
X: Adhesion with the release layer is slightly lowered.

(Concealment)
○: Excellent concealment and information cannot be read from the surface.
X: Poor concealability and information can be read from the surface.

  The evaluation results are shown in Table 1 below.

  As is apparent from the table, the scratch printed matter of the present invention is excellent in both scratch properties and adhesion, and in the case of scratching, most scraps can be made into a lump with a size of 2 to 4 mm due to the adhesiveness of the concealing scratch layer. I understand. However, from Comparative Examples 1 and 2, if there are too many concealing pigments, the adhesion is poor, and if there are too few concealing pigments, the scratching property is heavy, there is a problem in peelability, and there is a problem in concealing properties. Recognize. Further, it can be seen from Comparative Example 3 that when the urethane (meth) acrylate is not contained as the active energy ray-curable resin, the scraped residue becomes a fine powder when scratched.

  The scratch printed material of the present invention does not easily peel off due to rubbing between printed materials in the distribution stage, impact or friction in handling the printed material, and the user can easily scratch with coins, nails, etc. Since most scraps can be made into a lump with a size of 2 to 4 mm due to adhesiveness, there is no problem that the scraps become a fine powder and get into the nail or soil the surroundings. Suitable for use in etc.

FIG. 1 is a cross-sectional view showing a basic configuration of a scratch printed material of the present invention. FIG. 2 is a diagram for explaining a functional layer appropriately added as a scratch print in addition to the basic configuration of FIG.

Explanation of symbols

  1 is a printing substrate, 2 is an information layer, 3 is a peeling layer, 4 is a concealing scratch layer, 11 is a chromatic printing layer, 12 is an anchor layer, 13 is a protective layer, 14 is a white hiding layer, and 15 is a pattern printing 16 is an overcoat layer (OP layer), 17 is a fluorescent printing layer, 18 is a character printing layer, and 19 is a fluorescent printing layer.

Claims (4)

Containing a concealing scratch layer characterized by containing an active energy ray-curable resin composed of at least urethane (meth) acrylate and monofunctional (meth) acrylate and containing a concealing pigment in a proportion of 3 to 30% by mass . ink.   The ink for forming a concealing scratch layer according to claim 1, wherein the monofunctional (meth) acrylate is a linear or branched alkyl ester having 8 to 23 carbon atoms of (meth) acrylic acid. In a scratch printed matter comprising at least an information layer on a printing substrate, a release layer above the information layer, and a concealing scratch layer formed on the surface of the release layer, the concealing scratch layer comprises at least urethane (meta) It contains an active energy ray-curable resin composed of an acrylate and a monofunctional (meth) acrylate, and is formed of a concealing scratch layer forming ink containing a concealing pigment in a proportion of 3 to 30% by mass. Characteristic concealment scratch print. At least above the information layer in the printing substrate on which the information layer is formed, (1) a release layer forming ink containing an active energy ray-curable resin is printed by flexographic printing or a screen printer, and the active energy ray is irradiated. Forming a release layer by
(2) A concealing scratch containing an active energy ray-curable resin composed of at least urethane (meth) acrylate and monofunctional (meth) acrylate on the surface of the release layer and containing a concealing pigment in a proportion of 3 to 30% by mass. A method for producing a concealing scratch printed matter, comprising: sequentially performing a step of forming a concealing scratch layer by irradiating an active energy ray by printing a layer forming ink with a flexographic printing or a screen printer.

Images