JPH058533A - Peelable self-coloring pressure-sensitive recording sheet and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [Purpose] To manufacture a self-coloring type pressure-sensitive recording sheet that does not require release paper. [Structure] A self-coloring type pressure-sensitive recording sheet is coated with a release agent composed of a radiation-curable silicone resin and cured by irradiation with radiation, thereby maintaining good pressure-sensitive recording characteristics and water resistance. A peelable pressure-sensitive recording material having oil resistance, scratch resistance and peelability is obtained. An adhesive layer can be provided on the back surface of the obtained release-type pressure-sensitive recording material to obtain a label pressure-sensitive recording material that does not require release paper. [Effect] By forming a release layer on the pressure-sensitive recording layer of a radiation-curable release agent, a self-coloring type pressure-sensitive recording material having water and oil resistance and good pressure-sensitive recording characteristics can be obtained, and label pressure-sensitive recording When used as a body, release paper is unnecessary.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a release type self-coloring pressure-sensitive recording sheet, in which a radiation curable silicone resin layer is formed on a single-form self-coloring pressure-sensitive recording layer provided on a support. Release type self-developing pressure-sensitive recording sheet having a release layer consisting of water-resistant, chemical-resistant, oil-resistant and scratch-resistant recording sheets for dust generation control, such as labels, slips, and clean room recording paper. It can be used as.

[0002]

2. Description of the Related Art Self-developing pressure-sensitive recording sheets are developed from so-called carbonless copying papers and are also called self-contained papers. 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. Convenient with the step of applying a substance (hereinafter referred to as a color developer) A manufacturing method by two-layer coating consisting of two steps (including one in which the coating order is reversed), the above two-step components, or one of Each microcapsule is uniformly mixed and coated in a single layer (Japanese Patent Publication No. 47-16096).
No. publication) is known. In such a self-developing pressure-sensitive recording sheet, since the total amount of the color-developing agent and the color-developing agent are present in the vicinity of each other, it is easy to obtain a high color-developing density, but it is not intended due to friction during manufacturing or handling. There is a problem that intentional colored stains are likely to occur.

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, such a self-coloring pressure-sensitive recording sheet is often used for sticking continuous slips to luggage or as a lower sheet, and therefore, water resistance, oil resistance, stain resistance, and recordability are required at the same time. , It was extremely difficult to meet those conditions at the same time. Furthermore, in a continuous slip, when one of them is used for pasting, the lower paper must be a release paper, and it is often used in the lowest layer in the slip structure, so that the color density is inevitably low. Met. Further, in such a configuration, release paper having the same area is required, and the release paper discharged when, for example, continuous labeling is not only a significant obstacle to the work, but also peeling is generally performed. Since the paper cannot be recycled, there is a problem of disposal, and there is a problem that the combined thickness of the pressure sensitive paper and the release paper becomes thick when used.

Up to now, for example, a method of providing a laminate layer by a vacuum adhesion method on the recording layer of a self-coloring pressure-sensitive recording sheet (Japanese Patent Publication No. Sho 49-10857) or a recording sheet having a plastic layer by a melt lamination method ( (Japanese Utility Model Laid-Open No. 52-149709) and examples of providing a release layer on these protective layers are known. But,
In reality, when a protective layer is provided by melt laminating or laminating, unnecessary coloring stains can be prevented, but only unsatisfactory ones have been obtained at the expense of the originally required coloring performance. The reality was that there was nothing.

In the method of coating a polymerizable monomer or oligomer on the self-coloring type pressure-sensitive recording layer to form a coating by heating or energy rays, or the method of coating a soluble polymer solution and drying to form a coating, Although a thin protective layer can be formed, the microcapsules are destroyed to cause remarkable color fog, or the microcapsules are surrounded by a resin, and the original self-coloring type pressure-sensitive recording property is almost lost. It fell to the point where it was impossible.

[0006]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a peeling type self-coloring pressure-sensitive recording sheet without reducing the original color developability and reducing the color fog caused by rubbing and at the same time being water resistant. It is an object of the present invention to provide a self-coloring pressure-sensitive recording sheet which satisfies the requirements of oil resistance, oil resistance, stain resistance, etc. and has peeling property.

[0007]

Means for Solving the Problems The inventors of the present invention have found the following methods as a result of earnest research to solve the above problems. That is, in a self-coloring type pressure-sensitive recording sheet comprising a recording layer containing microcapsules containing a color-developing agent and a coating material containing a color-developing agent simultaneously or in a laminated state on a paper or film support, The invention is a release type self-coloring pressure-sensitive recording sheet comprising a release layer made of a silicone resin cured by irradiation with radiation, and a label using the release type self-coloring pressure-sensitive recording sheet. The radiation-curable silicone resin used in the present invention is a silicone resin in which an acryloyl group or a methacryloyl group is introduced into the terminal or side chain of the molecular main chain of polydialkylsiloxane, and may contain an inorganic pigment. The peelable self-coloring pressure-sensitive recording sheet of the present invention is a recording layer containing a coating material containing a microcapsule containing a color-developing agent and a color-developing agent on at least one surface of a paper or film support, simultaneously or in a laminated state. It is obtained by applying a radiation-curable silicone resin to the above and curing by irradiation with radiation. Radiation irradiation in this case is preferably ultraviolet irradiation, electron beam irradiation, or both. An adhesive layer may be provided on the back surface of the peelable self-coloring pressure-sensitive recording sheet used in the present invention to be used as a peeling self-coloring pressure-sensitive recording label.

In this release type self-coloring pressure-sensitive recording sheet, release paper is not required, which is not only cost-effective, but also the release layer also serves as an overcoat layer, and the gloss, water resistance and resistance It has excellent chemical resistance and scratch resistance, and since it does not require an overcoat layer or laminate layer on the self-coloring type pressure-sensitive recording layer, the overlaid layer becomes thin and color develops with good recording density during pressure-sensitive recording. It became clear that it was possible.

The details of the present invention will be described below. As the base paper used as the support of the pressure-sensitive recording material of the present invention, general paper such as glassine paper, high-quality paper, art paper, coated paper can be used, and wood pulp, synthetic pulp, filler, sizing agent, paper Raw materials commonly used in papermaking, such as strength enhancers and dyes, can be used as necessary. As a support, plastic sheet such as polyethylene, polypropylene, polyethylene terephthalate, polyamide, etc. and synthetic paper or non-woven fabric made of these synthetic fibers, or laminated paper, metal foil, or metal foil with synthetic resin laminated on one side or both sides It is also possible to use mica paper, glass paper, etc.

The self-coloring type 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, a microcapsule protective agent, and 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.

As the wall material of the microcapsule, polyurethane, polyurea, epoxy resin, urea / formalin resin, melamine / formalin resin, etc. can be used.

As the color former, 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, acidic polymers. (For example, phenol / formaldehyde resin, salicylic acid-based resin or metal salts thereof, etc.) can be used.

The peelable self-coloring pressure-sensitive recording sheet of the present invention may be provided with a protective coating layer, an adhesive layer, a peeling layer, a color former layer or a developer layer on the back surface thereof, either alone or simultaneously. Further, the surface of the present invention may be provided with a printing layer, an ink receiving layer, a writing layer, a color developing agent layer, a color developing agent layer, a pressure sensitive adhesive layer, a release layer and the like.

The binder used for forming the pressure-sensitive recording layer in the present invention includes starches, hydroxyethyl cellulose, methyl cellulose, ethyl cellulose,
Cellulose derivatives such as carboxymethyl cellulose,
Proteins such as casein and gelatin, oxidized starch,
Ester compound Water-soluble 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 Water-soluble synthetic polymer compounds such as acid ester / methacrylic acid terpolymer, alkali salt of styrene / maleic anhydride copolymer, latex, polyacrylamide, styrene / maleic anhydride copolymer, latex, ethylene / Water-soluble adhesive such as alkali salt of maleic anhydride copolymer, polyvinyl acetate, polyurethane, polyacrylic ester, styrene / butadiene copolymer, acrylonitrile / butadiene copolymer, methyl acrylate / butadiene copolymer Acrylonitrile / butadiene / acrylic acid copolymers, such as latex and ethylene / vinyl acetate copolymer.

Examples of pigments used in the pressure-sensitive recording layer include diatomaceous earth, talc, kaolin, calcined kaolin, calcium carbonate, magnesium carbonate, titanium oxide, zinc oxide, silicon oxide, aluminum hydroxide, and urea-formalin resin. Can be mentioned.

In addition, zinc stearate as an auxiliary agent,
Higher fatty acid metal salts such as calcium stearate. Waxes such as paraffin, oxidized paraffin, polyethylene, oxidized polyethylene, stearic acid amide, and castor wax. Further, a dispersant such as sodium dioctyl sulfosuccinate and a sulfonic acid-modified polyvinyl alcohol, an ultraviolet absorber such as a benzophenone type or a benzotriazole type, a surfactant, a fluorescent dye and the like are added as necessary.

In the pressure-sensitive recording material of the present invention, as a method for forming the pressure-sensitive recording layer, there are known a blade coating method, an air knife coating method, a gravure coating method, a roll coating coating method, a bar coating method, a drop curtain coating method and the like. Coating methods are available. After drying, the pressure-sensitive recording layer is preferably subjected to a smoothing treatment with a calendar.

Further, in the field of pressure-sensitive recording material manufacturing, 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 can be added as needed.

Further, as the constitution of the present invention, calcium carbonate, talc, between the support and the recording layer are used for obtaining the color density.
Silica, clay, barium sulfate, magnesium carbonate, magnesium silicate, lead sulfate, white lead, zinc white, zinc sulfide,
Satin white, titanium oxide, antimony oxide, mica, bentonite, calcium silicate, gypsum, inorganic pigments such as aluminum hydroxide or polystyrene, polyvinyltoluene, styrene / divinylbenzene copolymer, polymethylmethacrylate, urea / formaldehyde polymer There is no problem with providing an undercoat layer containing fine organic pigments such as polyethylene.

The release agent for forming the release layer used in the present invention is preferably an aqueous emulsion of the release agent or a radiation-curable silicone resin. As the release agent, various silicone compounds, fluorine compounds and long chain alkyl groups are used. The radiation-curable silicone resin is a resin containing acryloyl group or methacryloyl group at the terminal or side chain of the molecular main chain of a general silicone resin (mainly polydimethylsiloxane). An acrylate, a silicone-containing methacrylate, or a derivative thereof. The product name is FM071
1, FM0721, FM0725, PS583 (above,
Chisso Corporation, KP-600, X-62-7100,
X-62-7112, X-62-7140, X-62-
7144, X-62-7153, X-62-7157,
X-62-1158, KNS-5200, X-62-7
166, X-62-7168, X-62-7177, X
-62-7180, X-62-7181, X-62-7
192, X-62-7200 X-62-7203, X-
62-7205, X-62-7931 (above, Shin-Etsu Chemical Co., Ltd.), RC149, RC300, RC450, RC
802, RC710, RC720 (above, Gold Schmidt), EBECRYL350, EBECRYL1
360 (above, Daicel UCB Co., Ltd.) and the like. Furthermore, acrylates or methacrylates containing long-chain alkyl groups and their silicone-modified compounds are also good radiation-curable release agents. These may be used alone or in combination of two or more. In addition, in order to increase the surface strength of the release layer, or to improve the radiation curability, a general ultraviolet curable resin or an electron beam curable resin may be added to these radiation curable silicone resins as a curing aid. It can be used by mixing within a range that does not excessively affect the peel strength.

For the purpose of preventing sticking or blocking, organic or inorganic pigments can be contained in the resin forming these release layers. For example, kaolin, calcined kaolin, talc, wax, diatomaceous earth, calcium carbonate, aluminum hydroxide. , Magnesium hydroxide, magnesium carbonate, titanium oxide, barium carbonate, urea-formalin resin, and plastic beads such as styrene.

An intermediate layer can be provided between the pressure-sensitive recording layer and the release layer for the purpose of reducing the penetration of the release agent into the pressure-sensitive recording layer, and preferably the intermediate layer is coated with a water-soluble polymer. It is a dried layer. Examples of the water-soluble polymer mentioned here include the following substances.

As natural and semi-synthetic polymers, modified starch compounds such as starch, oxidized starch, etherified starch, dialdehyde starch, esterified starch, alginic acid compounds such as sodium alginate and propylene glycol alginate, casein, gelatin. , Pullulan, dextran, chitin, chitosan,
Examples thereof include modified cellulose compounds such as rubber latex, gum arabic, funori, natural gum, dextrin, methyl cellulose, ethyl cellulose, hydroxy cellulose and carboxymethyl cellulose. As the synthetic polymer, completely saponified or partially saponified polyvinyl alcohol, acetoacetylated polyvinyl alcohol, an esterified product of polyvinyl alcohol and polyvalent carboxylic acid,
Carboxy modified polyvinyl alcohol, sulfonic acid modified polyvinyl alcohol, olefin modified polyvinyl alcohol, nitrile modified polyvinyl alcohol,
Amide-modified polyvinyl alcohol, modified polyvinyl alcohol compounds such as pyrrolidone-modified polyvinyl alcohol, polyethylene glycol, polyacrylic acid amide, polyacrylic acid, ammonium polyacrylate,
Examples thereof include polyacrylic acid compounds such as sodium polyacrylate, polyvinylpyrrolidone, polyethyleneimine, polyvinyl ether, polymaleic acid copolymer, polyacrylamide, and water-soluble alkyd resin. Although it is not a water-soluble polymer in a strict sense, it has a high synthetic content such as styrene / maleic anhydride copolymer, styrene / butadiene copolymer, butadiene / methacrylate copolymer, acrylonitrile / butadiene / acrylic acid latex. An emulsion of molecules dispersed in water can be used instead of the water-soluble polymer solution. As the water-soluble polymer, the above polymers may be used alone or in the form of an aqueous solution by mixing them, and if necessary, a defoaming agent, a dispersant and the like may be used in combination.

The coating amount of the release layer and the coating amount of the intermediate layer are not limited, but it is desired that the coating amount be thinner for the purpose of avoiding a reduction in writing pressure, and preferably 0.2 g / m ² to 10 g.
g / m ² or less, more preferably 0.5 g / m ^{2 to} 3 g / m
It is within the range of ² or less. Examples of the method of applying the radiation-curable silicone resin of the present invention and the resin forming the intermediate layer include gravure roll and transfer roll coater, bar coater, roll coater, air knife coater, U comma coater, AKKU coater, smoothing coater, and 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 drop curtain coater, slide coater, die coater, etc. A coater may be used.

The release type self-coloring pressure-sensitive recording sheet according to the present invention may be used by printing on these supports, the self-coloring type pressure-sensitive recording layer, the water-soluble polymer intermediate layer or the cured release layer. it can. Further, in the present invention, surface treatment such as corona treatment for improving the adhesiveness and wettability may be performed without any problem.

The ultraviolet irradiation device used in the present invention is as follows:
For example, there are a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, a metal halide lamp, and the like, and there is an ozoneless type that generates less ozone. Generally, a plurality of lamps having an output of 30 w / cm or more are used in parallel.

The electron beam irradiation used in the present invention has an accelerating voltage of 100 to 1000 KV, more preferably an electron beam accelerator of 100 to 300 KV, in terms of penetrating power and curing power.
It is preferable that the absorbed dose of one pass is 0.5 to 20 Mrad. If the accelerating voltage or the electron beam irradiation dose is lower than this range, the electron beam penetrating power is too low to perform sufficient curing, and if it is higher than this range, not only the energy efficiency deteriorates, but also the resin, There are unfavorable effects on quality such as decomposition of additives and reduction of strength of base paper.

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.
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.

The pressure-sensitive recording material of the present invention may be subjected to character printing or tint block printing on the support or on the pressure-sensitive recording layer, and the release layer according to the present invention may be provided thereon. The peelable self-coloring sheet of the present invention can be used as a series of copying sheets together with other pressure-sensitive recording sheets by providing a color-forming layer, a color-developing layer, or both on the back surface at the same time. The peelable self-coloring pressure-sensitive recording sheet of the present invention is combined with other peeling-type self-coloring pressure-sensitive recording sheets, carbonless copying sheets, carbon copying sheets, adhesive sheets, printing sheets, transparent films, etc. Can be used as a sheet.

[0034]

The present invention provides a self-coloring pressure-sensitive recording sheet,
Taking advantage of the fact that the radiation-curable silicone resin coated on the recording layer does not easily penetrate into the recording layer, it is cured at room temperature by irradiation with ultraviolet rays or electron beams immediately after coating to form a protective film having releasability. The cured peelable protective film does not cause color fog and has good color development under pressure, and has excellent scratch resistance, water resistance, oil resistance, stain resistance, dust generation suppression, etc. A release type self-coloring pressure-sensitive recording sheet that can be used not only as a recording sheet but also as a release sheet is obtained.

[0035]

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. Further, the value indicating the smear amount is the smear amount after drying unless otherwise specified.

Preliminary Operation (Preparation of Self-Coloring Type Pressure-Sensitive Recording Layer) Microcapsules containing a color-forming agent used in the self-coloring type pressure-sensitive recording layer were prepared by mixing 10 parts of crystal violet lactone with Hisol SAS N-2.
It was heated and dissolved in 90 parts of 96 (manufactured by Nippon Petrochemical Co., Ltd.) to obtain an internal phase oil. 10 parts of melamine and 25 parts of 37% formalin were heated together with 100 parts of water at pH 8 to obtain a melamine / formalin initial polycondensate. Next, the internal phase oil was emulsified into 150 parts of a 5% styrene / maleic anhydride copolymer aqueous solution, and the above melamine / formalin polycondensate was added to the emulsion to maintain the system pH at 5.6. Liquid temperature 70 ℃
It was kept for 2 hours to obtain a microcapsule dispersion liquid containing a color former having a melamine / formalin resin film. The average particle size of the obtained microcapsules was about 6 μm.

The coating material for the self-coloring type pressure-sensitive recording layer was prepared by the following formulation. The unit is dry weight part. Microcapsules containing color former 100 parts Developer (PR26298 manufactured by Sumitomo Durez Co., Ltd.) 50 parts Starch particles 300 parts Kaolin clay 70 parts Oxidized starch 100 parts

A self-coloring pressure-sensitive recording sheet was prepared as follows. That is, a self-coloring pressure-sensitive recording sheet was obtained by coating a high-quality paper having a basis weight of 40 g / m ² with a self-coloring pressure-sensitive recording layer having the above composition so that the coating amount was 8 g / m ² .

Example 1 A UV curable silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., trade name KNS5300) was 0.8 g / m on a recording surface of a release type self-coloring pressure-sensitive recording sheet prepared in a preliminary operation with a 4-roll coater. ^It was applied so that it would be No. ^2, and was applied with an ultraviolet irradiation device (Rapid Cure, manufactured by Ushio Denki Co., Ltd.) to obtain a peeling type self-coloring pressure-sensitive recording sheet.

Example 2 An electron beam curable resin silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., trade name x-62-7) was applied to the recording surface of the self-coloring pressure-sensitive recording sheet prepared in the preliminary operation using a four roll coater.
168) was applied at a coating amount of 0.6 g / m ² and was introduced into an electron beam irradiation device (made by Nisshin High Voltage, Curetron) which was subjected to nitrogen substitution, and the electron beam acceleration voltage was 200 kV and the irradiation current was 20 mA. Was irradiated with an electron beam of 3 Mrad to obtain a peeling type self-coloring pressure-sensitive recording sheet.

Example 3 Silica / alumina compound as a pigment, Shilton AMT-100 (manufactured by Mizusawa Chemical Industry Co., Ltd.) was used as a pigment on the recording surface of the self-coloring pressure-sensitive recording sheet prepared in the preliminary operation by using a four roll coater. Beam curable resin containing 20% of silicone resin (Shin-Etsu Chemical Co., Ltd., trade name x-62-716
8) was applied at a coating amount of 0.8 g / m ² and electron beam irradiation was carried out in the same manner as in Example 2 to obtain a peeling type self-coloring pressure-sensitive recording sheet.

Example 4 An electron beam curable resin (Aronix M309, Toagosei Kagaku Kogyo Co., Ltd.) was used as a curing aid on the recording surface of the self-coloring pressure-sensitive recording sheet prepared in the preliminary operation by using a four roll coater. Electron beam curable resin containing 5% Silicone resin (Shin-Etsu Chemical Co., Ltd., trade name x-62-716)
8) was applied at a coating amount of 0.8 g / m ² and was introduced into an electron beam irradiation device (made by Nisshin High Voltage, Curetron) which had been subjected to nitrogen substitution, and the electron beam acceleration voltage was 200 kV and the irradiation current was 2
Irradiation with an electron beam of 1.5 Mrad was carried out under the condition of 0 mA to obtain a peeling type self-coloring pressure-sensitive recording sheet.

Example 5 On the recording surface of the self-coloring pressure-sensitive recording sheet prepared in the preliminary operation, a 5% solution of cationized starch was dried at a dry weight of 0.1 using an air knife coater as an intermediate layer comprising a water-soluble polymer. It was coated so as to have a concentration of 5 g / m ² and dried.
Furthermore, using a 4-roll coater on it, electron beam curable resin silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., trade name x-
62-7168) A mixed resin of 95% and styrene beads 5% was applied at an application amount of 0.6 g / m ² , and electron beam irradiation was carried out in the same manner as in Example 2 to obtain a release type self-coloring pressure-sensitive recording sheet. Obtained.

Example 6 An ultraviolet-curable silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., trade name KNS5300) was applied to the recording surface of a release type self-coloring pressure-sensitive recording sheet prepared in a preliminary operation using a vertical free-fall curtain coater. It was coated on the self-coloring type pressure-sensitive recording layer so as to have a content of 0.8 g / m ^2, and was irradiated with ultraviolet rays by an ultraviolet irradiation device to obtain a peeling-type self-coloring type pressure-sensitive recording sheet.

Example 7 An acrylic emulsion type pressure-sensitive adhesive (manufactured by Toyo Ink, trade name BPW-3110H) was coated on the back surface of the release type self-coloring pressure-sensitive recording sheet obtained in Example 1 with an applicator to a coating thickness of 20 μm. Apply to be (wet),
It was dried with warm air at 50 ° C. for 3 minutes and cooled at room temperature to form a release type self-coloring pressure-sensitive recording sheet having a pressure-sensitive adhesive layer. This sample showed good peeling properties when peeled off even after labeling itself by overlapping.

Example 8 Instead of the high-quality paper having a basis weight of 40 g / m ² used in the preliminary operation, a synthetic paper having a basis weight of 40 g / m ² (manufactured by Oji Yuka Co., Ltd.)
A peeling-type self-coloring pressure-sensitive recording sheet was obtained in the same manner as in Example 1 except for the above.

Comparative Example 1 The release type self-coloring pressure-sensitive recording sheet obtained in the preliminary operation was used for evaluation as it was without providing a release layer.

Comparative Example 2 A peeling type self-coloring pressure-sensitive recording sheet obtained in a preliminary operation was
Thermosetting silicone resin (Shin-Etsu Chemical Co., Ltd., trade name K
L-838) is a low temperature curing platinum catalyst (trade name CAT P
L-8) was mixed with 1%, and the solid content was adjusted to 0.
A peeling-type self-coloring pressure-sensitive recording sheet having a peeling layer was obtained by coating at 6 g / m ² and thermosetting with a hot air circulation dryer at 60 ° C.

Comparative Example 3 A low-density polyethylene (about 7 μm) was applied to the recording surface of the release type self-coloring pressure-sensitive recording sheet prepared in the preliminary operation at the lowest coating thickness (about 7 μm) that can be continuously produced by using a polyethylene melt laminator. Density 0.918 g / cm ³ ,
Melt index 7) is laminated and a thermosetting silicone resin (Shin-Etsu Chemical Co., Ltd., trade name KL-
838) is a low temperature curing type platinum catalyst (trade name CAT PL-
8%) was mixed with 1% and solid content was 0.6 g with a gravure roll.
/ M ² and heat-cured with a hot air circulation dryer at 60 ° C. to obtain a release type self-coloring pressure-sensitive recording sheet having a release layer.

Comparative Example 4 Emulsion type silicone release agent (trade name: KM763, manufactured by Shin-Etsu Chemical Co., Ltd.) 10% and sodium alginate 90% (on the recording surface of the release type self-coloring pressure-sensitive recording sheet prepared in the preliminary operation) (Solid solids content) solution is applied at a dry coating amount of 1.0 g / m ² , heat-cured with a hot air circulation dryer at 60 ° C., and a release type self-coloring pressure-sensitive recording having a release layer. Got the sheet.

The peeling type self-coloring pressure-sensitive recording sheets obtained in Test Examples 1 to 7 and Comparative Examples 1 to 5 had color density, color development speed, copyability, abrasion resistance, oil resistance, water resistance, peel strength, and The residual adhesion rate and the rub-off were evaluated. The respective results are shown in Table 1.

[Color density] The color density of each peeling type self-coloring pressure-sensitive recording sheet is Macbeth reflection when the color density of the second sheet from the top when a plurality of sheets are superposed and a certain weight is applied from above. Measured with a densitometer, the value of a peeling type self-coloring pressure-sensitive recording sheet having no protective layer such as an intermediate layer and a peeling layer (produced in Comparative Example 1; hereinafter referred to as comparative product) was 100.
Is expressed as a relative value.

[Color development speed] The color development speed was judged on the basis of superiority or inferiority as compared with the comparative product according to the color development condition in the color development density test.

[Copyability] Copyability was expressed by the relative value, with 100 being the case of the comparative product, based on the number of peeling-type self-coloring pressure-sensitive recording sheets having a coloration sufficiently recognizable in the color development test.

[Abrasion resistance] The abrasion resistance was judged by rubbing the surface of each peeling type self-coloring pressure-sensitive recording sheet on the recording layer side lightly with steel wool, and the coloring condition.

[Oil resistance and water resistance] For oil resistance and water resistance, one drop of xylene or water is dropped on the recording layer side of each peeling type self-coloring pressure-sensitive recording sheet, and it is permeated to the back side. It was judged by time.

[Peeling Strength] A pressure-sensitive adhesive (manufactured by Toyo Ink Co., Ltd., product name BPS) was coated on a high-quality paper and used as a standard pressure-sensitive adhesive sheet. The peelable pressure-sensitive recording material obtained (width: 15 m
m) is left in a thermo-hygrostat at 20 ° C and a humidity of 65% for 24 hours, then pressure-bonded to a standard pressure-sensitive adhesive sheet with a pressure roller of 2000 g and left in a thermo-hygrostat at 20 ° C and a humidity of 65% for 2 hours. After that, the results are shown in Table 1 with the load when peeling was continuously performed with Tensilon (manufactured by Toyo Baldwin Co., Ltd.) under the conditions of a peeling angle of 180 ° and a peeling speed of 30 cm / min.

[Residual Adhesion Rate] The peelable pressure-sensitive recording material (width: 15 mm) thus obtained was placed in a thermo-hygrostat at 20 ° C. and a humidity of 65% for 2 days.
After standing for 4 hours, the standard pressure-sensitive adhesive sheet was pressure-bonded with a pressure-bonding roller having a weight of 2000 g, and the temperature was 20 ° C., the humidity was 65%, and the pressure was 0.
Pressure was applied for 24 hours under the condition of 1 kg / cm ² . After peeling the standard pressure-sensitive adhesive sheet from the peelable pressure-sensitive recording material, it was attached to a 0.5 mm thick stainless steel plate with a well-polished surface and pressure-bonded with a pressure-bonding roller weighing 2000 g, at 20 ° C. and a humidity of 65.
%, The load when continuously peeled with a tensilon under the conditions of a peel angle of 180 ° and a peel rate of 30 cm / min is determined as peel strength. Next, a standard adhesive sheet is attached to a stainless steel plate having a thickness of 0.5 mm, the surface of which is well polished, and the temperature is 20 ° C., the humidity is 65% and the pressure is 0.1.
Pressure was applied for 24 hours under the condition of kg / cm ² . After returning to normal pressure, crimp it with a pressure roller with a weight of 2000g.
After left for 1 hour in a thermo-hygrostat at a temperature of 65 ° C. and a humidity of 65%, the load when continuously peeling with a tensilon at a peeling angle of 180 ° and a peeling speed of 30 cm / min is obtained as the peeling strength. The residual adhesion rate R (%) is calculated by the equation 1. The peel strength of the pressure-sensitive adhesive sheet after contact with the peel-type pressure-sensitive recording body is A = A, and the peel strength of the pressure-sensitive adhesive sheet not in contact with the peel-type pressure-sensitive recording body = B.

[0059]

## EQU1 ## R = (A / B) × 100

[Love-off] The peeling layer of the peelable pressure-sensitive recording material was strongly rubbed with a finger, and peeling of the peeling layer was visually judged. When peeling was observed on the surface, it was indicated as a love-off defect by x, and when slight peeling of the peeling layer was observed, it was indicated by Δ, and the results are shown in Table 1.

[0061]

[Table 1]

Evaluation: Obtained in Examples 1 to 8,
The release-type self-coloring pressure-sensitive recording sheets having a silicone resin layer cured by irradiation with radiation are all smooth,
Compared to the current self-coloring pressure-sensitive recording sheet (Comparative Example 1), it does not cause color fog, and has excellent water resistance, oil resistance, and abrasion resistance, and also in terms of colorability, color density, and color development speed. , Was comparable to the current self-developing pressure-sensitive recording sheet. In addition, the copyability when a plurality of sheets were piled up was also comparable to the current self-coloring pressure-sensitive recording sheet. When used in combination with the pressure-sensitive adhesive layer, it was possible to form a release layer having good peel strength and less migration of silicone on the pressure-sensitive adhesive layer side. Also, the peeling surface strength was high and no rub-off occurred.

On the other hand, as a comparison, the self-coloring pressure-sensitive recordings obtained in Comparative Examples 2 to 4 having a release layer by thermosetting, a release layer formed on a laminate layer, and an emulsion type release layer by thermosetting. The sheet has a recording property such as a release agent impregnating the recording layer to impair the color developability, a peeling surface having a weak strength, causing a rub-off, and a release component migrating to the adhesive layer to reduce the residual adhesion rate. The release characteristics were not at a satisfactory level. Although the release type self-coloring pressure-sensitive recording sheet having the molten polyethylene laminate layer obtained in Comparative Example 3 is superior in water resistance, oil resistance and abrasion resistance to the current self-coloring pressure-sensitive recording sheet. In addition, the color developability was deteriorated, and in particular, the number of copies when printing was made by stacking a plurality of sheets was inferior to the current product or the peeling type self-coloring pressure-sensitive recording sheet of the example.

[0064]

INDUSTRIAL APPLICABILITY According to the present invention, a self-coloring pressure-sensitive recording sheet is provided with a release layer made of a silicone resin which is cured by irradiation with radiation, so that the self-coloring pressure-sensitive recording sheet does not cause color fog. Water resistance while maintaining color development characteristics such as copyability, color density, and color development speed,
It can provide oil resistance and abrasion resistance. The release layer on the self-coloring type pressure-sensitive recording layer also functions as a protective film, and can impart effective scratch resistance, low ambient contamination, and dust generation suppressing property. Further, since the article of the present invention has a good peeling property on the surface, it does not require a release paper even when it is used as a voucher for sticking, it is highly economical and a copy with a high recording density can be obtained. It can also be used for many purposes such as sticking slips, recording, and dust-free recording paper.

Claims (9)

[Claims] 1. A self-coloring type pressure-sensitive recording sheet comprising a paper or film support, on which microcapsules containing a color-forming agent and a recording layer containing a color-developing agent in a single layer or in a laminated state are formed. A release type self-coloring pressure-sensitive recording sheet comprising a release layer made of a silicone resin cured by irradiation with radiation, provided on the recording layer. 2. The radiation-cured silicone resin is a polydialkylsiloxane molecular main chain terminal,
Alternatively, the release type self-coloring pressure-sensitive recording sheet according to claim 1, which is obtained by curing a silicone resin having an acryloyl group or a methacryloyl group introduced into its side chain. 3. The release type self-coloring pressure-sensitive recording sheet according to claim 1, wherein an organic or inorganic pigment is contained in the release layer cured by the irradiation of radiation. 4. The peeling-type peeling type self-coloring pressure-sensitive recording sheet according to claim 1, wherein an intermediate layer is provided between the recording layer and the peeling layer. 5. A radiation-curable silicone resin is applied onto a recording layer containing a microcapsule containing a color-developing agent and a color developer in a single layer or a laminated state on a paper or film support, and radiation is then applied. A method for producing a peeling-type self-coloring pressure-sensitive recording sheet, which comprises curing by irradiation. 6. The method for producing a peeling type self-coloring pressure-sensitive recording sheet according to claim 5, wherein the radiation irradiation is ultraviolet irradiation. 7. The method for producing a peeling type self-coloring pressure-sensitive recording sheet according to claim 5, wherein the radiation irradiation is electron beam irradiation. 8. The method for producing a release type self-coloring pressure-sensitive recording sheet according to claim 5, wherein the radiation-curable silicone resin is applied by a vertical free-fall curtain coater. 9. A self-coloring type pressure-sensitive recording sheet having a release layer made of a silicone resin cured by irradiation on a recording layer, wherein a release-type self-coloring feeling having an adhesive layer on the side not having the recording layer. Pressure record label.