JPH0624124A - Pressure-sensitive recording sheet for copying - Google Patents

Abstract

PURPOSE:To improve releasability and color developing properties without damaging self-color developing properties by curing a resin having specific viscosity at a fixed temperature before the application of electron rays within the specified range of electron-ray absorbed dose in an electron-ray curable resin layer. CONSTITUTION:A micro-encapsulated self-color developing type pressure-sensitive recording layer 2, a polyolefin laminating layer 3, an electron-ray curable resin layer 4, an opaque coating sheet 5 and a developer layer 6 are laminated on one surface of a support 1, thus forming thermal recording paper for copying. The electron-ray curable resin layer 4 is formed by using an electron-ray curable resin having viscosity at a temperature of 25 deg.C of 50cps or more before the application of electron rays such as polyester acrylate and curing the resin within the range of electron-ray absorbed dose of 0.5-50Mrad.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to pressure-sensitive recording, in which a single-form self-coloring type pressure-sensitive recording layer provided on a support and a color-developing agent having a pressure-sensitive coloring property are coated. A pressure-sensitive recording sheet for copying that integrates an opaque coating sheet (lower paper), and is a type that has non-exposure of recording, copyability, water resistance, chemical resistance, oil resistance, scratch resistance, and dust generation suppression property. Is a pressure-sensitive recording sheet for copying, which can be used as a recording sheet, a recording sheet, a label, a slip, a message, an entertainment item, a clean room recording sheet.

[0002]

2. Description of the Related Art The pressure-sensitive recording layer used in the present invention is a self-coloring pressure-sensitive recording type, which is developed from so-called carbonless copying paper. Also called paper. Its composition is a process of applying a coating of microcapsules containing a colorless dye (hereinafter referred to as a color former) on a support, and electron-accepting properties of acid clay, phenolic resin, organic acid substances, etc. on the coating. Conveniently the process of applying a substance (hereinafter referred to as a color developer) and a manufacturing method by two-layer coating consisting of two steps (including those in which the coating order is reversed), the above two components, or any one component Manufacturing method by microencapsulation, uniform mixing, and single layer coating (Japanese Patent Publication No.
No. 7-16096) is known. In such a self-coloring pressure-sensitive recording sheet, a color developing agent and a color developing agent are present in the vicinity, so a printed image with a high color density is easily obtained, but unintentional unintentional due to friction during manufacturing or handling. There is a problem that colored stains are likely to occur. As described above, the self-coloring pressure-sensitive recording sheet is destined to satisfy both the practically required coloring performance and the suppression of unnecessary coloring stains under the conditions under which it is used. Efforts are being made to satisfy both conflicting properties of dirt.

Further, in the self-coloring type pressure-sensitive recording sheet, the pressure-sensitive information is inevitably exposed to the public, and if it is desired to hide the information content, it should be put in a separate bag. I had to do it.

Up to now, for example, a method of providing a laminate layer by a vacuum adhesion method on a recording layer of a self-coloring pressure-sensitive recording sheet (Japanese Patent Publication No. Sho 49-10857) or a recording having a plastic layer by a melt lamination method. Known examples include a sheet (Japanese Utility Model Publication No. 52-149709) and a release layer provided on these protective layers. However, in reality, when a protective layer is provided by fusion lamination or lamination, unnecessary color stains can be prevented, but basically it is premised that the pressure-sensitive recording portion is exposed. The issue of record secrecy could not be resolved. In addition, a heat-sealing or thermoplastic resin coating layer is provided on the recording layer of a self-coloring type pressure-sensitive recording sheet, and the back surface is overlaid with an opaque coating sheet coated with a hot-melt type or thermoplastic type heat-sealing adhesive. , There is a method of integrating by hot pressing, but if it is hot pressed enough to be integrated, color fog in the pressure-sensitive recording layer will be caused and the commercial value will be lost, or resin with adhesive strength much weaker than adhesive strength will be used. There was no choice but to carry out integration with a light press by the adhesive force. Although this type of pressure-sensitive recording sheet has the concealment of recording,
Since it could be easily reattached, the confidentiality of the record was low.

In order to solve the above problems, the present applicants have proposed a pressure-sensitive recording layer, a polyolefin resin laminate layer, an electron beam as a pressure-sensitive recording sheet of a type that does not re-adhere once the opaque coating sheet is peeled off. An application was filed for a pressure-sensitive recording sheet in which a curable resin layer and an opaque coating sheet were sequentially provided. The pressure-sensitive recording sheet has not only good color development, water resistance, oil resistance, abrasion resistance, etc., but also complete nondisclosure of information, and an opaque coating sheet once peeled does not re-adhere. Therefore, the confidentiality of the information was high. In particular, in the step of integrating the sheet having the pressure-sensitive recording layer and the opaque coating sheet, they can be integrated with almost no pressing or heating, so that pressure fog does not occur in the pressure-sensitive recording layer, which is good. The pressure-sensitive recording sheet having a smooth background was obtained.

As a result of further studies on the pressure-sensitive recording sheet, the applicants have confirmed that the following problems may occur during actual use. That is, when the pressure-sensitive recording sheet is used as a slip for copying, a lower sheet for pressure-sensitive recording is used as an opaque covering sheet and integrated with a polyolefin resin laminate layer,
It can be used with pressure sensitive copy paper. By this method, copy (upper sheet), copy recording (lower sheet), and hidden recording (pressure-sensitive color recording under the polyolefin resin laminate layer) can be performed. However, the following problems may occur when an electron beam curable resin is used to bond the lower sheet. That is, when the self-coloring pressure-sensitive recording paper provided with the polyolefin resin laminate and the non-coated surface of the lower paper coated with the color developer are superposed with the electron beam curable resin interposed therebetween, Depending on the type, the developer on the lower paper is desensitized, and when used as a slip, the copy sensitivity is reduced. This trouble not only hinders the reading of the content of the pressure-sensitive copy, but is also aesthetically unfavorable and significantly impairs the commercial value. Further, depending on the electron beam irradiation method, the lower sheet does not peel off well, which hinders reading the internal record.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a self-coloring type pressure-sensitive recording sheet in which a lower sheet having a pressure-sensitive recording property is integrated by using an electron beam curable resin. Color information is not sacrificed, information is not disclosed if necessary, the lower paper has good peelability, and it does not re-adhere after the lower paper is once peeled, and the color on the lower paper is developed. An object of the present invention is to provide a pressure-sensitive recording sheet for copying having good properties.

[0008]

Means for Solving the Problems As a result of intensive studies on the above problems, the present inventors have found the following solution. That is, on one surface of the support, a color-forming agent or a color-developing agent, both or one of which is microencapsulated, is laminated individually, or a pressure-sensitive recording layer is mixed and applied.
In the pressure sensitive recording sheet for copying in which a polyolefin resin laminate layer, an electron beam curable resin layer, an opaque coating sheet, and a color developer are sequentially provided, the resin forming the electron beam curable resin layer performs electron beam irradiation. Before the viscosity at 25 ℃ 50
It is an invention of a pressure-sensitive recording sheet for copying, which is cps or more and the electron beam curable resin layer is cured in an electron beam absorbed dose range of 0.5 to 5.0 Mrad.

The present invention will be described in detail below. In the pressure sensitive recording sheet for copying of the present invention, the adhesive resin forming the electron beam curable resin layer provided on the recording surface by the action of the polyolefin resin laminate layer does not permeate into the pressure sensitive recording layer and the pressure sensitive recording is performed. High color density can be obtained in
It has excellent scratch resistance and abrasion resistance, and because it is integrated with the lower paper, the pressure-sensitive information can be exposed to the outside and handled without being exposed, and the lower paper can be peeled off if necessary. By doing so, it is possible to read the pressure-sensitive information recorded inside. Confidentiality is perfect because the lower paper that has been peeled off does not reattach. Since there is a color developer layer on the surface of the lower paper, pressure-sensitive printing can be performed accurately on the surface of the lower paper if pressure-sensitive printing is performed by overlapping with the upper paper coated with the color former or its capsule. it can. If you want to develop color only on the internal pressure-sensitive recording layer, use a printer with the ink ribbon removed to perform blanking without using upper paper, or apply desensitizing ink on the developer layer. Coloring on paper can be suppressed.

When an adhesive resin that does not dissolve in the polyolefin resin is applied on the polyolefin resin laminate layer and is sufficiently cured or crosslinked, the solidified electron beam curable resin layer has a cohesive force or a light anchor effect. Although it is adhered to the polyolefin resin laminate layer, it can be separated (peeled) from the polyolefin resin laminate layer with a light force. When separated once, the resin forming the electron beam curable resin layer is sufficiently solidified, so that it is not adhered to the polyolefin resin laminate layer again by pressurization or heating. The polyolefin resin laminate layer and the solidified electron beam curable resin layer transmit the writing pressure with almost no dispersion and absorption, so high color density can be obtained during pressure sensitive recording, and gloss and scratch resistance of the printed surface can be obtained. Since it has excellent abrasion resistance, and has an electron beam curable resin layer on the polyolefin resin laminate layer and a lower sheet as an opaque coating sheet, the pressure-sensitive recorded information is handled outside without being exposed or exposed. The pressure-sensitive information recorded inside can be read by peeling the lower sheet as necessary. Further, for the reasons described above, the information once disclosed has a characteristic that it cannot be hidden again (anti-re-adhesion property).

An epoch-making point in the present invention is that an electron beam curable resin having a viscosity at 25 ° C. of 50 cps or more is used for adhesion between the lower paper and the polyolefin resin laminate layer, and they are integrated by electron beam irradiation. It is in. When the lower paper and the polyolefin resin laminate layer on the pressure-sensitive recording layer are integrated with the electron beam curable resin, if the viscosity of the electron beam curable resin is smaller than this range, the electron beam curable resin will seep into the lower paper. May occur, which not only hinders the color development of the lower sheet, but also makes the lower sheet slightly transparent and allows the internal color recording to be hidden to be seen through. When the viscosity of the electron beam curable resin is above this range, it is considered that the penetration of the electron beam curable resin into the lower paper is suppressed, but the color development of the lower paper is not only good. In addition, since it is not heated, the polyolefin resin laminate layer does not curl or shrinks with the underlying paper, and wrinkles are suppressed, resulting in good internal pressure-sensitive recording and coloring of the underlying paper. The pressure-sensitive recording sheet for copying having the property is obtained.

As the support and the opaque coating sheet used in the pressure-sensitive recording sheet for copying of the present invention, general paper such as glassine paper, high-quality paper, art paper, coated paper, cast paper and the like can be used. Raw materials usually used in papermaking, such as pulp, synthetic pulp, fillers, sizing agents, paper-strengthening agents, and dyes, can be used as necessary. In addition, plastic sheets such as polyethylene, polypropylene, polyethylene terephthalate, polyamide, polyvinyl chloride, polyvinylidene chloride, and polymethylpentene, and synthetic paper or non-woven fabric made of these synthetic fibers, or synthetic resin on paper, on one side or both sides Laminated laminated paper, metal foil, or metal foil-paper bonded product, vapor-deposited paper, hologram-treated opaque sheet, synthetic resin film bonded product, mica paper,
Glass paper can also be used. These supports can be made opaque with inorganic or organic pigments, inks, toners and the like.

The pressure-sensitive recording layer that can be used in the present invention is not particularly limited, and any conventionally known one can be used. For example, a method of microencapsulation, a wall material of the microcapsule, a color former, an oil dissolving the color former, a color developer, an adhesive resin, a microcapsule protective agent, or the like. Examples of the microencapsulation method include a coacervation method (US Pat. No. 2,800,458), an interfacial polymerization method (Japanese Patent Publication No. 47-1763, etc.), an in situ polymerization method (Japanese Patent Publication No. 51-9079, etc.). Etc. can be used.

Polyurethane, polyurea, epoxy resin, urea / formalin resin, melamine / formalin resin and the like can be used as the wall material of the microcapsule.

Examples of color formers are triallylmethane compounds, diarylmethane compounds, xanthene compounds,
A thiazine-based compound, a spiropyran-based compound, or the like can be used, and is not particularly limited as long as it is generally used for pressure-sensitive recording materials and heat-sensitive recording materials.

As the oil for dissolving the color former, aromatic synthetic oils such as diarylalkane type, alkylnaphthalene type, alkylated biphenyl and hydrogenated terphenyl, and aliphatic synthetic oils such as kerosene, naphtha, paraffin oil and chlorinated paraffin are used. Oils, cottonseed oil, soybean oil, vegetable oils such as flaxseed oil and the like can be used.

As the protective agent for the microcapsules, cellulose powder, starch particles, talc, calcined kaolin, calcium carbonate and the like can be used.

Examples of developers include clays (eg, acid clay, attapulgite, etc.), organic acids (eg, aromatic carboxy compounds such as salicylic acid, or metal salts thereof), mixtures of organic acids and metal compounds, An acidic polymer (for example, phenol-formaldehyde resin, salicylic acid-based resin, or a metal salt thereof) or the like can be used.

In the present invention, as the binder used for forming the pressure-sensitive recording layer, starch, cellulose derivatives such as hydroxyethyl cellulose, methyl cellulose, ethyl cellulose and carboxymethyl cellulose, protein such as casein and gelatin, oxidized starch, ester compound. Aqueous natural polymer compounds such as saccharose such as starch, polyvinyl alcohol, modified polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, sodium polyacrylate, acrylic acid amide / acrylic acid ester copolymer, acrylic acid amide / acrylic acid ester / Methacrylic acid terpolymer, styrene /
Water-soluble synthetic polymer compounds such as alkali salts of maleic anhydride copolymer, latex, polyacrylamide, styrene / maleic anhydride copolymer, latexes, and water-soluble alkali salts of ethylene / maleic anhydride copolymer, etc. Adhesive resin, polyvinyl acetate, polyurethane, polyacrylic acid ester, styrene / butadiene copolymer, acrylonitrile / butadiene copolymer, methyl acrylate / butadiene copolymer, acrylonitrile / butadiene / acrylic acid copolymer, ethylene / Examples thereof include latex such as vinyl acetate copolymer.

The pigment used in the pressure-sensitive recording layer, the polyolefin resin laminate layer, or the electron beam curable resin layer includes diatomaceous earth, talc, kaolin, calcined kaolin,
Examples thereof include calcium carbonate, magnesium carbonate, titanium oxide, zinc oxide, silicon oxide, aluminum hydroxide and urea-formalin resin.

In addition, zinc stearate as an auxiliary agent,
Waxes such as higher fatty acid metal salts such as calcium stearate, paraffin, oxidized paraffin, polyethylene, oxidized polyethylene, stearamide, castor wax, etc., dispersant such as sodium dioctylsulfosuccinate, sulfonic acid modified polyvinyl alcohol, benzophenone type, An ultraviolet absorber such as a benzotriazole type, a surfactant, a fluorescent dye and the like are added as necessary.

In the pressure-sensitive recording sheet for copying of the present invention,
As the method for forming the pressure-sensitive recording layer, known coating methods such as blade coating method, air knife coating method, gravure coating method, roll coating coating method, bar coating method and drop curtain coating method can be used. The pressure-sensitive recording layer is preferably smoothed.

Further, a back coat is applied to prevent curling, a conductive treatment is applied to prevent jamming, and an undercoat layer is provided between the support and the pressure sensitive recording layer. Various known techniques in 1) can be added as necessary.

Further, as the constitution of the present invention, in order to obtain a high color density, calcium carbonate, talc, silica, clay, barium sulfate, magnesium carbonate, magnesium silicate, between the support and the pressure-sensitive recording layer, Inorganic pigments such as lead sulfate, lead white, zinc white, zinc sulfide, satin white, titanium oxide, antimony oxide, mica, bentonite, calcium silicate, gypsum, aluminum hydroxide, or polystyrene, polyvinyltoluene, styrene / divinylbenzene There is no problem in providing an undercoat layer containing fine organic pigments such as polymers, polymethylmethacrylate, urea / formaldehyde polymers, and polyethylene.

Examples of the polyolefin resin constituting the polyolefin resin laminate layer include the following substances. As polyethylene, high-density polyethylene,
Low density polyethylene, medium density polyethylene, linear low density polyethylene, ultra high molecular weight polyethylene, polypropylene as isotactic, atactic, a mixture thereof, a random copolymer or a block copolymer with ethylene, and other poly-3- Methyl pentene-1,
Polyethylene glycol terephthalate, polyvinyl chloride, polyvinylidene chloride, eval, ethylene vinyl acetate copolymer and the like can be used alone or in combination. However, in consideration of the adhesiveness to the electron beam curable resin layer, the releasability, and the anti-re-adhesion property, a polyolefin containing polyethylene, polypropylene or polymethylpentene (poly-4-methylpentene-1, TPX) as a main component. It is preferably a resin. The polyolefin resin laminate can be provided on the pressure-sensitive recording layer by melt extrusion of the above substances. As a pretreatment for the melt extrusion, the pressure-sensitive recording layer may be subjected to a known treatment such as corona treatment for improving the adhesiveness.

If necessary, an aqueous intermediate layer for improving the adhesiveness can be provided between the pressure-sensitive recording layer and the polyolefin resin laminate layer in a coating amount range that does not lower the pressure-sensitive recording sensitivity.

As the polyolefin resin laminate layer, a laminator such as a general melt extrusion die, T die, and multi-layer simultaneous extrusion die can be used. Also, a polyolefin resin laminate layer can be obtained by adhering a polyolefin resin film to a pressure-sensitive recording layer or an aqueous intermediate layer via an electron beam curable resin layer. Further, a polyolefin resin laminate layer provided on the pressure-sensitive recording layer,
Adhesion is possible even if the polyolefin resin laminate layers provided on the opaque coating layer are superposed and heat-sealed, but it is not so preferable due to the restriction of pressure fog on the pressure-sensitive recording layer.

In the present invention, of the electron beam curable resins that can be used as the resin forming the electron beam curable resin layer, representative ones are as follows:

(1) Polyester acrylate, polyester methacrylate; for example, Aronix M-53
00, Aronix M-5400, Aronix M-5
500, Aronix M-5600, Aronix M-
5700, Aronix M-6100, Aronix M
-6200, Aronix M-6300, Aronix M-6500, Aronix M-7100, Aronix M-8030, Aronix M-8060, Aronix M-8100 (above, Toa Gosei Chemical Industry Co., Ltd. trade name), Viscoat 700, Viscoat 3700 (above,
Product name of Osaka Organic Chemical Industry Co., Ltd., Kayarad HX-2
20, Kayarad HX-620 (Nippon Kayaku Co., Ltd.)
Product name) and the like.

(2) Urethane acrylate, urethane methacrylate; for example, Aronix M-1100, Aronix M-1200, Aronix M-1210,
Aronix M-1250, Aronix M-126
0, Aronix M-1300, Aronix M-13
10 (above, trade name of Toagosei Chemical Industry Co., Ltd.), viscoat 812, viscoat 823, viscoat 823 (above, trade name of Osaka Organic Chemical Industry Co., Ltd.), NK ester,
U-108-A, NK ester, U-4HA (above, Shin Nakamura Chemical Co., Ltd. trade name), etc. are mentioned.

(3) Monofunctional acrylate, monofunctional methacrylate, vinylpyrrolidone, acryloyl compound, acrylamide compound; for example, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate. , 2-hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, cyclohexyl acrylate, cyclohexyl methacrylate,
Acryloylmorpholine, benzyl acrylate, glycidyl methacrylate, N, N-dimethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, butoxyethyl acrylate, vinylpyrrolidone,
Acrylamide ether compound etc. Ethylene oxide-modified phenoxy phosphoric acid acrylate Ethylene oxide-modified butoxylated phosphoric acid acrylate, and other product names of Toagosei Kagaku Kogyo Co., Ltd., Aronix M-10
1, Aronix M-102, Aronix M-11
1, Aronix M-113, Aronix M-11
4, Aronix M-117, Aronix M-15
2, Aronix M-154 and the like.

(4) Polyfunctional acrylate, polyfunctional methacrylate; for example, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate,
Neopentyl glycol diacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, pentaerythritol diacrylate, dipentaerythritol hexaacrylate, isocyanuric acid diacrylate, pentaerythritol triacrylate , Isocyanuric acid triacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethylene oxide modified pentaerythritol tetraacrylate, propylene oxide modified pentaerythritol tetraacrylate, propylene oxide modified dipentaerythritol polyacrylate Relate, ethylene oxide-modified dipentaerythritol polyacrylate, such acrylate esters of pentaerythritol acrylate adduct. The product names of Toagosei Co., Ltd. are Aronix M-210 and Aronix M-21.
5, Aronix M-220, Aronix M-23
0, Aronix M-233, Aronix M-24
0, Aronix M-245, Aronix M-30
5, Aronix M-309, Aronix M-31
0, Aronix M-315, Aronix M-32
0, Aronix M-325, Aronix M-33
0, Aronix M-400, Aronix M-45
0, TO-458, TO-747, TO-755, TH
IC. TA2 etc. are mentioned.

(5) Silicone acrylate, silicone methacrylate; an acryloyl group at the terminal or side chain of the molecular main chain of a general silicone resin (mainly polydimethylsiloxane or polydialkylsiloxane),
Alternatively, a resin or a derivative thereof in which a methacryloyl group is introduced. The product names are FM0711, FM0721, FM07
25, PS583 (above, Chisso Corporation), KNS-5
0002, KNS-5100, KNS-5300, KP
-600, X-62-7052, X-62-7100,
X-62-7112, X-62-7140, X-62-
7144, X-62-7153, X-62-7157,
X-62-1158, KNS-5200, KNS-53
00, X-62-7166, X-62-7168, X-
62-7177, X-62-7180, X-62-71
81, X-62-7192, X-62-7200, X-
62-7203, X-62-7205, X-62-79
31, KM-875, X-62-7296A / B, X-
62-7305A / B, X-62-7028A / B, X
-62-5039A / B, X-62-5040A / B
(Above, Shin-Etsu Chemical Co., Ltd.), RC149, RC30
0, RC450, RC802, RC710, RC71
5, RC720, RC730 (above, Goldschmitt), EBECRYL350, EBECRYL136
0 (above, Daicel UCB Ltd.) and the like.

These resins alone have a viscosity range of 25 ° C.
If the resin has a viscosity of 50 cps or more, it can be used as it is, and even a resin having a viscosity lower than 50 cps at 25 ° C. can be mixed with another resin and used.

For the purpose of preventing blocking, thickening, and increasing the amount, it is possible to add organic or inorganic pigments to the resin forming these electron beam-curable resin layers. For example, kaolin, calcined kaolin, talc and wax. , Diatomaceous earth, calcium carbonate, aluminum hydroxide, magnesium hydroxide, magnesium carbonate, titanium oxide, barium carbonate, urea-formalin resin, and plastic beads such as styrene.

The coating amount of the electron beam curable resin layer is not limited, but it is desired that it is thinner for the purpose of avoiding a decrease in writing pressure as much as possible, preferably 0.5 to 30 g.
/ M ² or less, more preferably 1.0 to 20 g / m ² or less. Examples of the method for applying the resin for forming the electron beam curable resin layer of the present invention include a gravure roll and transfer roll coater, a bar coater, a roll coater, an air knife coater, a U comma coater, and AK.
KU coater, smoothing coater, micro gravure coater, air knife coater, reverse roll coater, 4 or 5 roll coater, blade coater, dip coater, bar coater, rod coater, kiss coater, gate roll coater, squeeze coater, falling curtain coater, Any coater such as a slide coater or a die coater may be used.

In the pressure-sensitive recording sheet for copying according to the present invention, these supports, the pressure-sensitive recording layer, the polyolefin resin laminate layer, and the opaque covering sheet can be used for letter printing or tint block printing. Further, in the present invention, in order to improve adhesiveness and wettability, surface treatment such as corona treatment, ozone treatment, and flame treatment on the pressure-sensitive recording layer, the polyolefin resin laminate layer, and the opaque coating sheet is not performed. No problem whatsoever.

Further, the pressure-sensitive recording sheet for copying of the present invention is
On its surface, pressure-sensitive recording surface, polyolefin resin laminate layer surface or back surface, a color former layer or developer layer, a protective coating layer, an electron beam curable resin layer, a release layer, a printing layer, a toner receiving layer, an ink receiving layer. A layer, a heat-sensitive recording layer, a writing layer, a magnetic recording layer and the like can be provided alone or simultaneously. Further, the pressure-sensitive recording sheet for copying of the present invention can be used as a series of copying sheets in combination with other pressure-sensitive recording sheet, back carbon copying sheet, adhesive sheet, printing sheet, transparent film and the like. There is no problem in processing a part or all of the recording sheet of the present invention such as die cutting, separating a part of the opaque coating sheet, processing perforations and printer feed holes.

In order to cure the electron beam curable resin used in the present invention by electron beam irradiation, the accelerating voltage is 100 to 1000 KV, more preferably 100 to 300 KV in terms of electron beam penetration and curing power. It is preferable to use a linear accelerator. It is preferable that the electron beam irradiation is such that the absorbed dose in the lower sheet is 0.5 to 5 Mrad. If the accelerating voltage or electron beam dose is lower than this range,
The penetrating power of the electron beam is too low to perform sufficient curing, which may cause color inhibition of the lower paper.If it is larger than this range, not only the energy efficiency deteriorates, but also the resin and the additive Disadvantages such as disintegration and deterioration of the strength of the base paper appear unfavorably on the quality, and particularly the peelability of the lower paper is deteriorated.

The electron beam accelerator may be, for example, an electro curtain system, a scanning type, a double scanning type or the like. In the electron beam irradiation step, the overcoat layer can be cured while a synthetic resin film, a metal foil, a metal drum, or the like is brought into close contact with the overcoat layer and the surface shape thereof is transferred.

During electron beam irradiation, if the oxygen concentration is high, the curing of the electron beam curable resin is hindered, so nitrogen,
Oxygen concentration is less than 600ppm, preferably 400ppm by replacing with inert gas such as helium and carbon dioxide.
Irradiation is preferably performed in an atmosphere suppressed below.

[0042]

In the pressure-sensitive recording sheet for copying of the present invention, the adhesive resin which does not dissolve the polyolefin resin is sufficiently cured in the polyolefin resin laminate layer on the pressure-sensitive recording layer,
Alternatively, since it is crosslinked, the solidified electron beam curable resin layer adheres to the polyolefin resin laminate layer by cohesive force or a light anchor effect, but can be separated (peeled) from the polyolefin resin laminate layer by light force. The opaque coating sheet and the adhesive resin are sufficiently adhered by a sufficient anchor effect, chemical bond and cohesive force. Once the adhesive resin is separated from the polyolefin resin laminate layer, the resin that constitutes the electron beam curable resin layer is sufficiently solidified, so that the polyolefin resin laminate layer is re-formed again.
It does not adhere due to pressure or heat. Since the polyolefin resin laminate layer and the solidified electron beam curable resin layer transmit the writing pressure without being dispersed or absorbed, a high color density can be obtained at the time of pressure-sensitive recording,
The printed surface has excellent gloss, scratch resistance, and abrasion resistance, and because it has an electron beam curable resin layer and a lower sheet on the polyolefin resin laminate layer, the pressure-sensitive information is disclosed to the outside.
It can be handled without being exposed, and the lower paper can be peeled off as necessary to read the information pressure-sensitively recorded inside. Furthermore, for the reasons described above, the information once disclosed cannot be hidden again (re-adhesion prevention property).
It has the feature. Since the electron beam curable resin has a sufficiently high viscosity, it does not penetrate into the lower paper even when it comes into contact with the lower paper, and as a result, high color development of the lower paper is guaranteed and the lower paper does not become transparent. Has concealment.

[0043]

The present invention will be described in detail below with reference to examples, but the contents of the present invention are not limited to the examples.
All parts and% shown below are based on weight.

Example As a pressure-sensitive recording paper, a commercially available self-coloring type pressure-sensitive recording paper (manufactured by Mitsubishi Paper Mills, Diaself, Super N100, basis weight 100) was used.
g / m ² ) was used. Polypropylene (density: 0.900 g / cc) was laminated on the pressure-sensitive recording surface to a thickness of 10 μm using a melt extrusion die as a polyolefin resin laminate layer. An electron beam curable resin shown in Table 1 was applied onto a polyolefin resin laminate layer by an offset gravure coater so that the amount was 8 g / m ^2, and a lower paper having a developer layer thereon (Mitsubishi Paper Milling Co., Ltd., Mitsubishi NCR
Under supermarket, N30, basis weight 30g / m ² ) non-coated surfaces were superposed and introduced into an electron beam irradiation device (Electron Curtain, manufactured by Energy Science Co.), and the absorbed dose shown in Table 1 was obtained at an electron beam acceleration voltage of 200kV. Electron beam irradiation was performed so as to cure the electron beam curable resin, and a target pressure-sensitive recording sheet for copying was obtained. In the table below, Aronix is a trade name of electron beam curable resin manufactured by Toagosei Kagaku Kogyo Co., Ltd., and Kayarad is a trade name of electron beam curable resin manufactured by Nippon Kayaku Co., Ltd.

[0045]

[Table 1]

Comparative Example 1 As a pressure-sensitive recording paper, a commercially available self-coloring type pressure-sensitive recording paper (manufactured by Mitsubishi Paper Mills, Diaself, Super N100, basis weight 100) was used.
g / m ² ) was used. Polypropylene (density: 0.900 g / cc) was laminated on the pressure-sensitive recording surface to a thickness of 10 μm using a melt extrusion die as a polyolefin resin laminate layer. An electron beam curable resin shown in Table 2 was applied on a polyolefin resin laminate layer by an offset gravure coater so that the amount was 8 g / m ^2, and a lower paper having a developer layer thereon (Mitsubishi Paper Milling Co., Ltd., Mitsubishi NCR
Under supermarket, N30, basis weight 30g / m ² ) non-coated surfaces were superposed and introduced into an electron beam irradiation device (Electron Curtain, manufactured by Energy Science Co., Ltd.) and the absorbed dose shown in Table 2 at an electron beam acceleration voltage of 200kV. Electron beam irradiation was performed so as to cure the electron beam curable resin, and a target pressure-sensitive recording sheet for copying was obtained.

[0047]

[Table 2]

Test: The pressure-sensitive recording sheets for copying obtained in Example 1 and Comparative Example 1 were sufficiently integrated without peeling of the lower sheet due to printing, cutting, mailing or the like. A commercially available pressure-sensitive recording paper was superposed on the pressure-sensitive recording sheet for copying, and a color slip, a printability, and a record exposure property were evaluated as a copy slip. The respective results are shown in Tables 3 and 4.

[Lower paper color development test] The color density of the lower paper of each pressure-sensitive recording sheet for copying is recorded and printed by an impact printer equipped with an ink ribbon on the upper paper, and then the upper paper is separated. Then, the color development of the lower paper was measured. Measure the color density with Macbeth reflection densitometer,
It was expressed as a relative value based on the color density of the lower paper when the upper paper and the lower paper were simply overlaid and printed in the same manner. 90
% Or more is sufficient as a record.

[Internal Coloring Test] The internal color density of each of the pressure-sensitive recording sheets for copying was recorded and printed on the upper paper by an impact printer equipped with an ink ribbon, and then the lower paper was peeled off to remove the polyolefin. The internal color development was measured from above the resin laminate layer. The color density was measured with a Macbeth reflection densitometer and expressed as a relative value based on the color density of the self-coloring pressure-sensitive recording paper before lamination.
90% or more is sufficient for deciphering the record.

[Lower paper releasability] When the lower paper of each of the copying pressure-sensitive recording sheets for copying is manually peeled from the polyolefin resin laminate layer, the lower paper which can be peeled without being damaged is lower paper releasability. When the lower paper was partially destroyed and remained on the polyolefin resin laminate layer, the lower paper peelability was judged to be poor.

[Hiddenness] An impact printer in which an ink ribbon is mounted on top of the upper paper by printing with a desensitizing ink on a part of the lower paper of each of the copying pressure-sensitive recording sheets for copying. The upper sheet is separated from the upper sheet, and the upper sheet is separated when the upper sheet is not printed and the color is only printed inside but the recorded contents cannot be read from the upper sheet. In the separated stage, the print contents on the copying pressure-sensitive recording sheet were slightly readable, and in the separation stage, the print contents on the copying pressure-sensitive recording sheet were readable well.

[Confidentiality] Disclosure of the record obtained by peeling the lower sheet of the obtained pressure-sensitive recording sheet for copying and printing with a printer, and re-bonding the lower sheet by pressing or heating again. Those that were inferior and did not re-adhere were rated as excellent.

[0054]

[Table 3]

[0055]

[Table 4]

Evaluation ... Each of the pressure-sensitive recording sheets for copying obtained in the examples had good color developability of the lower sheet,
Also, the internal recording is good when the lower paper is peeled off,
There was no problem with the peelability of the lower paper. When the lower paper is integrated with the electron beam curable resin having a viscosity of less than 50 cps at 25 ° C. used in the comparative example, it is considered that the electron beam curable resin causes bleeding. Was not good, and there was a problem that the lower paper became transparent and the internal print was transparent. When the lower sheet was peeled off, the pressure sensitive recording sheets for copying obtained in the examples had good confidentiality because the cured electron beam curable resin did not re-adhere to the polyolefin resin laminate layer at all.

[0057]

The pressure-sensitive recording sheet for copying of the present invention is a pressure-sensitive recording sheet for copying which has excellent coloring properties on the surface (lower sheet) of the pressure-sensitive recording sheet for copying and which can conceal the printed contents. Yes, it is effective for recording and communication when hiding the contents.

[Brief description of drawings]

FIG. 1 is a sectional view of a pressure-sensitive recording sheet for copying according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support 2 Self-coloring type pressure sensitive recording layer 3 Polyolefin resin laminating layer 4 Electron beam curable resin layer 5 Opaque coating sheet 6 Developer layer 7 Lower paper

Claims (1)

[Claims] 1. A pressure-sensitive recording layer or a polyolefin resin laminate layer, which is formed by laminating a color-forming agent or a color-developing agent, both or one of which is microencapsulated, individually on one surface of a support, or by mixing and coating them. , An electron beam curable resin layer, and an opaque coating sheet coated with a color developer or its microcapsules on one side not in contact with the electron beam curable resin layer in order. The resin constituting the resin layer has a viscosity of 50 cps or more at 25 ° C. before being irradiated with an electron beam, and the electron beam curable resin layer is cured in an electron beam absorbed dose range of 0.5 to 5.0 Mrad. A pressure-sensitive recording sheet for copying characterized in that