JPH06171211A - Pressure sensitive recording sheet - Google Patents

Abstract

PURPOSE:To manufacture a pressure sensitive recording sheet wherein a recording content into an inside is concealed irrespective of decrease of a recording area in a surface. CONSTITUTION:A pressure sensitive recording layer 4 wherein a color coupler or a developer of which both sides or one side are microcapsulated are respectively independently laminated or mixed to be applied to a side surface of a base material, and an opaque coating sheet 1 processed by ground tint printing for prevention of seeing through are integrated with a thermoplastic resin laminate layer 3 by making the pressure sensitive recording layer 4 and the ground tint printing surface respectively inside. Thereby, a content recorded by printing on an inner surface of the pressure sensitive recording sheet can be thoroughly concealed, and the pressure sensitive recording sheet which is excellent in beauty can be provided without decreasing a recording area of the surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to pressure-sensitive recording, and comprises a single-form self-coloring type pressure-sensitive recording layer provided on a support, and an opaque coated sheet having a tint block print for preventing see-through. An integrated pressure-sensitive recording sheet, which is a type of recording sheet with non-exposure, non-transparency, copyability, water resistance, chemical resistance, oil resistance, scratch resistance, and dust generation suppression It is a pressure-sensitive recording sheet that can be used as recording paper for labels, slips, correspondence, entertainment products, and clean rooms.

[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. Must.

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. Sheet (Japanese Utility Model Publication No. 52-149709), an example of providing a release layer on these protective layers, or a self-coloring type pressure-sensitive recording layer, a soluble polymer solution is applied and dried to form a film. It is known how to provide it. However, in these methods, the color fog is remarkably caused by the destruction of the microcapsules, or the microcapsules are covered with the resin, so that the original self-coloring pressure-sensitive recording property is almost lost, and the color density and the color developing speed are decreased. Also, since these methods basically assume that the pressure-sensitive recording portion is exposed, the problem of non-disclosure of the recording cannot be solved.

The present applicant has previously proposed that a self-coloring type pressure-sensitive recording layer,
It has been filed that a pressure-sensitive recording sheet having a structure in which a thermoplastic resin laminate layer and an opaque coating sheet are sequentially stacked solves these problems and also conceals the pressure-sensitive recording information. Still had the following problems. That is, there is a problem that the hidden information content recorded by pressure may be legible when viewed from the front or back. Naturally, such transparency can be prevented by providing a tint block print on the front surface or the back face for preventing see-through, but the portion provided with the tint block print cannot perform other recording, and the recording surface is drastically reduced. And there was a problem that it was not aesthetically pleasing.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a self-coloring type pressure-sensitive recording sheet in which an opaque coating sheet is integrated, without sacrificing its original self-coloring property, and if necessary information. A pressure-sensitive recording sheet which completely has the non-disclosure, has no transparency, does not reduce the recordable area of the surface tint block printing, and does not re-adhere after the opaque coating sheet is once peeled off. To do.

[0007]

The present inventors have found the following method as a result of earnest research for solving the above-mentioned problems. That is, on one surface of the support, a pressure-sensitive recording layer in which a color-developing agent or a color-developing agent, both or one of which is microencapsulated, is individually laminated, or mixed and applied.
It is an invention of a pressure-sensitive recording sheet, characterized in that an opaque coating sheet provided with a tint block print for preventing see-through on one surface in contact with the thermoplastic resin laminate layer is integrated via the thermoplastic resin laminate layer. In the pressure-sensitive recording sheet, it is necessary that the thermoplastic resin laminate layer is strongly adhered to the pressure-sensitive recording layer side and weakly adhered to the opaque coated sheet side. Further, in the pressure-sensitive recording sheet, the surface of the opaque coating sheet which is in contact with the thermoplastic resin laminate layer may be subjected to a release treatment. The release treatment is preferably performed outside the tint block printing (on the side of the thermoplastic resin laminate layer), but it is also possible to perform the release treatment and the tint block printing at the same time by adding a release agent to the tint block printing itself. is there.
In the pressure-sensitive recording sheet of the present invention, a color developer or a microcapsule thereof may be coated on one surface of the opaque coated sheet which is not in contact with the thermoplastic resin laminate layer.
Further, in the pressure-sensitive recording sheet, a heat-sensitive recording layer may be provided on one surface of the opaque coating sheet which is not in contact with the thermoplastic resin laminate layer. With the pressure-sensitive recording sheet having these structures, it is possible to satisfy both the non-transparent property of recording and the securement of the surface recording area.

The details of the present invention will be described below. In the pressure-sensitive recording sheet of the present invention, the pressure-sensitive recording layer and the opaque coating sheet can be integrated by the action of the thermoplastic resin laminate layer,
Moreover, by changing the adhesive strength of the thermoplastic resin laminate layer between the pressure-sensitive recording layer side and the opaque covering sheet side, it is possible to peel off the opaque covering sheet having a relatively weak adhesive strength with the thermoplastic resin laminate layer. The thermoplastic resin laminate layer is a layer formed by substantially melt extrusion, and by adhering to both the support having the pressure-sensitive recording layer and the opaque coating sheet, and strongly adhering to the pressure-sensitive recording layer side, The pressure-sensitive recording sheet of the present invention is formed by weakly adhering to the opaque coating sheet side.

Since the pressure-sensitive recording sheet of the present invention has an opaque coating sheet, it has excellent scratch resistance and abrasion resistance on the printed surface, and since it is integrated with the opaque coating sheet, the pressure-sensitive recorded information is recorded. Can be handled without being exposed or exposed to the outside, and the opaque cover sheet can be peeled off as necessary to read the information pressure-sensitively recorded inside. Since the opaque cover sheet is printed with a tint block pattern for preventing see-through only on the inner surface (the thermoplastic resin laminate layer side), the confidentiality of information is high and the surface of the opaque cover sheet (that is, the Information that may be exposed to the outside (address, advertisement, etc.) because it is not necessary to print a tint block on the surface of the pressure-sensitive recording sheet of the configuration)
Can be recorded. The background pattern for preventing see-through may be printed on the entire surface of the thermoplastic resin laminate layer side of the opaque covering sheet or on a part of the surface corresponding to the portion to be pressure-printed. Once peeled off, the opaque coated sheet does not re-adhere, so the confidentiality is perfect.

The surface of the opaque cover sheet may have a developer layer, and if pressure-sensitive printing is performed by superimposing it on an upper paper coated with a color former or its capsule, the surface of the opaque cover sheet will be covered. It is possible to perform pressure-sensitive recording with high accuracy.
A heat-sensitive recording layer can be provided on the surface of the opaque coated sheet, and heat-sensitive recording can be performed on the surface. If you want to develop color only on the internal pressure-sensitive recording layer, use a printer without the ink ribbon to perform blanking without using top paper, or apply desensitizing ink on the developer layer to make it opaque. Coloring on the cover sheet can be suppressed.

The adhesive strength with the thermoplastic resin laminate layer is a relative comparison between the pressure sensitive recording layer side and the opaque coated sheet side, but preferably the adhesive strength of the thermoplastic resin laminate layer on the pressure sensitive recording layer side. Indicates strong adhesion, specifically, 100 gf / 1 in a 180 ° peel test (300 mm / min, the same applies below) in a Tensilon universal tensile tester.
It is preferable that the adhesive strength (peeling strength) is 5 mm or more. When the adhesive strength of the thermoplastic resin laminate layer is less than this range, peeling trouble may occur when peeling from the opaque coating sheet. Further, if it is above this range, the pressure-sensitive recording layer develops color even if the thermoplastic resin laminate layer is forcibly peeled from the pressure-sensitive recording layer, so that the adhesive strength is sufficient.

The adhesive strength between the opaque coating sheet and the thermoplastic resin laminate layer must be weakly adherent, and in principle, if the adhesive strength between the thermoplastic resin laminate layer and the pressure-sensitive recording layer is less than that. You can peel off the opaque cover sheet,
If the adhesive strength is too close, the thermoplastic resin laminate layer may float from the pressure-sensitive recording layer (partially peeling off), or the pressure-sensitive recording layer may develop color when peeling off the opaque coating sheet, Depending on the thickness of the opaque cover sheet, the opaque cover sheet may be broken when peeled off. Such troubles differ in the adhesive strength range that occurs depending on the thickness and type of the opaque coating sheet, the thickness of the thermoplastic resin laminate layer, or the color developability of the pressure-sensitive recording layer. The adhesiveness with the resin laminate layer is
It is preferable that the adhesive strength (peeling strength) is less than 100 gf / 15 mm in a 180 ° peeling test in a Tensilon universal tensile tester. Among them, it is particularly preferable that the adhesive strength is less than 85 gf / 15 mm so that the opaque coated sheet can be easily peeled off, the fog of the pressure-sensitive recording layer at the time of peeling is small, and the opaque coated sheet is not broken midway. From the point of, it is preferable. The minimum adhesive strength between the opaque coating sheet and the thermoplastic resin laminate layer is preferably 3 gf / 15 mm or more in a 180 ° peel test in a Tensilon universal tensile tester in order to avoid peeling trouble during recording and transportation.

Generally, when laminating a thermoplastic resin, the adherend and the polyolefin resin are adhered to each other by a physical anchor effect or by a weak hydrogen bond. Naturally, it is possible to improve the adhesiveness by increasing the ratio of chemical bonds between the polyolefin resin and the adherend by undercoating the adherend or using a reactive polyolefin resin. The adhesive strength between the thermoplastic resin laminate layer and the adherend has such an anchor effect,
It can be strengthened or weakened by changing the ratio of hydrogen bonds and chemical bonds. That is, in order to increase the adhesive strength, the resin temperature and the adherend temperature during melt lamination are increased, the adherend surface is roughened, the press pressure during lamination is increased to enhance the anchor effect, and Corona treatment, flame treatment, UV irradiation,
This is achieved by performing a pretreatment such as ozone treatment to introduce a polar group and increasing the proportion of hydrogen bonds.

On the contrary, in order to weaken the adhesive strength, the resin temperature and the temperature of the adherend during melt lamination are lowered, the surface of the adherend is smoothed, and the press pressure during lamination is lowered to lower the anchor effect. Or, to reduce the proportion of polar groups without pretreatment such as corona treatment, flame treatment, ultraviolet irradiation, ozone treatment on the adherend, or increase the water content if it is a porous substance such as paper. Reduce the proportion of hydrogen bonds that contribute to adhesion, apply surfactants, silicone or fluorine compounds, long-chain alkyl compounds, etc.,
Achieved by addition. As a matter of course, using a multi-layer simultaneous extrusion die, the highly adherent polyolefin resin on the adherend side, the non-adherent side is simultaneously melt extruded so that the low-adhesive polyolefin resin is in contact, the adherend, It is possible to change the adhesive strength by bonding non-adhered bodies at the same time. Even in this case, the thermoplastic resin laminate layer is substantially one layer and is not peeled off from the high-adhesion and low-adhesion polyolefin resin layers.

When a pressure-sensitive recording sheet in which the thickness of the thermoplastic resin laminate layer is within a certain range and the pressure-sensitive recording layer has high color developability, the opaque coating sheet almost disperses and absorbs writing pressure. Since it transmits without pressure, high color density can be obtained at the time of pressure sensitive recording, and the gloss, scratch resistance, and abrasion resistance of the printing surface are excellent, and also because an opaque coating sheet is provided on the thermoplastic resin laminate layer. The pressure-sensitive recorded information can be handled without being exposed and exposed to the outside, and the opaque coated sheet can be peeled off as necessary to read the pressure-sensitive recorded information inside. Further, the information once disclosed has a characteristic that it cannot be hidden again (preventing re-adhesion).

As the resin constituting the thermoplastic resin laminate layer, polyethylene (low density, medium density, high density, linear low density polyethylene), polypropylene, polytrimethylpentene, polybutene, ethylene vinyl acetate copolymer, ethylene ethyl General-purpose melt extrusion resins such as acrylate copolymer, ethylene acrylic acid copolymer, ethylene methyl acrylate copolymer, ethylene vinyl alcohol copolymer, ethylene methacrylic acid copolymer and its salts, vinyl chloride, vinylidene chloride They can be used alone or as a mixture. The mixing method is not particularly limited, and any method can be used. For example, an extruder for kneader, a heating kneading roll, a Banbury mixer, a predetermined amount of a polyolefin resin using a kneader, and if necessary, various additives (release agent, slip agent, pigment, antioxidant, neutralizing agent) Agent, etc.) and melt-mixed, and then crushing and pelletizing the mixture, or by directly charging the mixture into an extruder in a so-called simple blend state and extrusion-coating, or when polymerizing one of the polyolefin resins. A method using a mixed resin obtained by copolymerizing other components can be used.

The thickness of the thermoplastic resin laminate layer is 10 to 10.
The thickness is preferably in the range of 50 μm, and when the thickness of the thermoplastic resin laminate layer is within this range, the gloss, scratch resistance and abrasion resistance of the printed surface are improved without lowering the color developability of the pressure sensitive recording layer. Not only that, but it also functions as a peeling layer that peels off the opaque coated sheet. If the thickness of the thermoplastic resin laminate layer is smaller than this range, when the opaque coating sheet is peeled off, the thermoplastic resin laminate layer peels off from the pressure sensitive recording layer, or the laminate layer floats or the background fog of the pressure sensitive recording layer occurs. Sometimes, it may be difficult to read the record. If the thickness of the thermoplastic resin laminate layer is thicker than this range, the recording density may be reduced when pressure-sensitive printing is performed, which may not be preferable as a recording sheet.

To integrate the pressure-sensitive recording layer and the opaque coating sheet with a thermoplastic resin laminate, a general laminator such as a melt extrusion die, a T die, and a multi-layer simultaneous extrusion die can be used. As a pretreatment for melt extrusion, a known treatment for improving adhesion such as corona treatment or frame treatment may be performed on the pressure-sensitive recording layer or the opaque coating sheet. As a matter of course, the adhesiveness and the releasability can be controlled by changing the degree of surface treatment of the pressure-sensitive recording layer and the opaque coating sheet. At the time of laminating by melt extrusion, either the support having a pressure-sensitive recording layer or the opaque coating sheet may be positioned on the cooling roll side or the press roll side, but a pressure-sensitive recording layer having particularly high color-developing sensitivity is provided. When used, it is preferable to use an opaque cover sheet on the press roll side.

The resin forming these thermoplastic resin laminate layers can contain organic or inorganic pigments, organic dyes, and dye amounts. For example, kaolin, calcined kaolin, talc, pyrophyllite, diatomaceous earth, carbonic acid. calcium,
Examples thereof include aluminum hydroxide, magnesium hydroxide, magnesium carbonate, titanium oxide, barium carbonate, urea-formalin resin, plastic beads such as styrene, ultramarine blue, crystal violet, and leuco dye coloring material.

Between the pressure-sensitive recording layer and the thermoplastic resin laminate layer, if necessary, polyvinyl alcohol, gelatin, polyacrylic acid and salts thereof, various latexes such as casein, starch, and rubber latex for improving adhesion. The aqueous polymer intermediate layer can be provided in a coating amount range that does not reduce the pressure-sensitive recording sensitivity.

As the support and the opaque coating sheet used in the pressure-sensitive recording sheet 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, wood pulp, Raw materials commonly used in papermaking, such as synthetic pulp, fillers, sizing agents, paper-strengthening agents, and dyes, can be used as necessary.
Further, plastic sheets such as polyethylene, polypropylene, polyethylene terephthalate, polyamide, polyvinyl chloride, polyvinylidene chloride, and polymethylpentene, and synthetic papers and nonwoven fabrics made of these synthetic fibers,
Or laminated paper with synthetic resin laminated on one side, metal foil, or laminated product of metal foil and paper, vapor-deposited paper, opaque sheet subjected to hologram treatment, laminated product with synthetic resin film, mica paper, glass Paper etc. can also be used. These supports can be made opaque with inorganic or organic pigments, inks, toners and the like. In addition, a pressure-sensitive recording layer or a part thereof (developing agent layer or color-developing agent layer), a heat-sensitive layer, a magnetic recording layer, or a printing layer is provided on the non-bonded surface of the opaque coating sheet or the surface having no pressure-sensitive recording layer. It can also be provided.

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, 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.

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

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, 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 copolymers, latex, polyacrylamide, styrene / maleic anhydride copolymers, latexes, water-soluble alkali salts of ethylene / maleic anhydride copolymers, etc. Adhesive, polyvinyl acetate, polyurethane, polyacrylic acid ester, styrene / butadiene copolymer, acrylonitrile / butadiene copolymer, methyl acrylate /
Butadiene copolymer, acrylonitrile / butadiene /
Examples thereof include latex such as acrylic acid copolymer and ethylene / vinyl acetate copolymer.

Pigments used in the pressure-sensitive recording layer and the thermoplastic resin laminate layer include diatomaceous earth, talc, kaolin, calcined kaolin, calcium carbonate, magnesium carbonate, titanium oxide, zinc oxide, silicon oxide, and hydroxide. Aluminum, a urea-formalin resin, etc. are mentioned.

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 of the present invention, the method for forming the pressure-sensitive recording layer is as follows: blade coating method, air knife coating method, gravure coating method, roll coating coating method,
Known coating methods such as a bar coating method and a 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 a 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.

Further, the pressure-sensitive recording sheet of the present invention has a coloring agent layer or a pressure-sensitive recording surface, a thermoplastic resin laminate layer surface, the front surface or the back surface of the opaque coating sheet, or the back surface of the pressure-sensitive recording sheet. Developer layer, protective coating layer, release layer,
A printing layer, a tint block printing layer, a toner receiving layer, an ink receiving 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 of the present invention includes other pressure-sensitive recording sheets, back carbon copy sheets,
It can be used as a series of copy sheets by combining with an adhesive sheet, a printing sheet, a 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.

[0035]

In this pressure-sensitive recording sheet, an opaque coating sheet having a tint block print inside is integrated with a self-coloring type pressure-sensitive recording sheet by a thermoplastic resin laminate layer to record the surface of the opaque coating sheet. The information of the self-coloring type pressure-sensitive recording layer can be completely hidden without sacrificing the coloring property of the self-coloring type pressure-sensitive recording layer while ensuring a sufficient area, and by the function of the thermoplastic resin laminate layer. It has a function of preventing re-adhesion after the opaque coating sheet is once peeled off.

[0036]

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. Also,
Unless otherwise noted, the value indicating the smear amount is the smear amount after drying.

Example 1 As a pressure-sensitive recording paper, a commercially available self-coloring type pressure-sensitive recording paper (manufactured by Mitsubishi Paper Mills, Diaself, MCD130, basis weight 130 g /
m ² ) was used after corona treatment. Coated paper as opaque cover sheet (made by Mitsubishi Paper Mill, Pearl Light A,
A woven paper having a basis weight of 52 g / m ² and having a tint block printed on one side for preventing see-through was used. Low density polyethylene (density: 0.918 g / cc, MFR: 12 g / 10 min) and high density polyethylene (density: 0.955 g / cc, MF) using a melt extrusion die as a thermoplastic resin laminate layer.
(R: 37 g / 10 min) was melt-extruded to a thickness of 20 μm, and the pressure-sensitive recording layer surface and the printing surface of the opaque coating sheet were attached to each other to obtain a target pressure-sensitive recording sheet.

Example 2 As a pressure-sensitive recording paper, a commercially available self-coloring type pressure-sensitive recording paper (manufactured by Mitsubishi Paper Mills, Diaself, MCD130, basis weight 130 g /
m ² ) was used after corona treatment. Paper under pressure paper with a developer layer as an opaque coating sheet (made by Mitsubishi Paper Mills,
Under the Mitsubishi NCR Super, an N40, basis weight 40 g / m ² ) non-coated surface was used, which was subjected to tint block printing for full-scale transparency prevention. A low-density polyethylene (density: 0.918 g /
cc, MFR: 15 g / 10 min) and polypropylene (density: 0.905 g / cc, MFR: 20 g / 10 min) in an equal amount mixture were melt extruded to 20 μm, and the pressure-sensitive recording layer surface and the opaque coating sheet were formed. Stick the printed surfaces together,
A target pressure-sensitive recording sheet was obtained.

Example 3 As a pressure-sensitive recording paper, a commercially available self-coloring type pressure-sensitive recording paper (manufactured by Mitsubishi Paper Mills, Diaself, Super N160, basis weight 165) was used.
g / m ² ) was used. Base paper for thermal paper as an opaque coating sheet (made by Mitsubishi Paper Mills, PV220A base paper, basis weight 50 g /
A non-thermosensitive coated surface of m ² ) having a tint block printing for preventing see-through was used. Low density polyethylene (density:
0.918 g / cc, MFR: 15 g / 10 minutes) and polypropylene (density: 0.905 g / cc, MFR: 20)
(g / 10 minutes) 3: 2 mixture was melt-extruded so as to have a thickness of 15 μm, and the pressure-sensitive recording layer surface and the printing surface of the opaque coating sheet were bonded together. A heat-sensitive layer was coated on a base paper for heat-sensitive paper and dried to obtain a target pressure-sensitive recording sheet.

Example 4 As the pressure-sensitive recording paper, a commercially available high-sensitive self-coloring type pressure-sensitive recording paper (manufactured by Mitsubishi Paper Mills, Diaself, MCD N130, basis weight 130 g / m ² ) was used. As the opaque covering sheet, a single-sided cast paper having a basis weight of 70 g / m ² is used, a non-cast surface is printed with a tint block printing for preventing see-through, and a silicone resin emulsion (X, manufactured by Shin-Etsu Chemical Co., Ltd. -52-151, 3% PM as catalyst
6 A / B) was applied in a solid content of 1 g / m ² and dried by heating. Corona treatment was applied to the pressure-sensitive recording surface, and a low-density polyethylene (density: 0.918 g / cc, MFR:
12g / 10min) and high density polyethylene (Density: 0.9
55 g / cc, MFR: 37 g / 10 min) weight ratio 3:
Pressing line pressure 28k so that 1 mixture becomes 15 g / m ^2.
Melt extrusion was performed at g / cm, and the pressure-sensitive recording layer and the release-treated surface of the opaque coating sheet were bonded together as a bonding surface to obtain an intended pressure-sensitive recording sheet.

Example 5 As the pressure-sensitive recording paper, a commercially available high-sensitivity self-coloring type pressure-sensitive recording paper (manufactured by Mitsubishi Paper Mills, Diaself, MCD N130, basis weight 130 g / m ² ) was used. As an opaque coating sheet, single-sided cast paper having a basis weight of 70 g / m ² was used, and an ink containing 3% by weight of a fluorine compound (Florard FC721, manufactured by 3M Co., Ltd.) was used as a release agent for tint block printing on the non-cast surface for prevention of see-through. went. Corona treatment was applied to the pressure-sensitive recording surface, and low-density polyethylene (density: 0.918 g / c was used as a thermoplastic resin laminate layer using a melt extrusion die.
c, MFR: 12 g / 10 min) and polypropylene (density: 0.90 g / cc, MFR: 27 g / 10 min) in a weight ratio of 3: 1 mixture at a press linear pressure of 28 kg / cm so as to be 20 g / m ^2. The composition was melt-extruded, and the pressure-sensitive recording layer and the opaque coating sheet were pasted together with the tint block printed surface as the pasting surface to obtain a target pressure-sensitive recording sheet.

Comparative Example 1 A pressure-sensitive recording sheet was obtained in the same manner as in Example 1 except that the opaque covering sheet was not provided with the tint block printing for preventing see-through.

Comparative Example 2 A pressure-sensitive recording sheet was obtained in the same manner as in Example 2 except that the opaque coated sheet was not provided with the tint block printing for preventing see-through.

Comparative Example 3 A pressure-sensitive recording sheet was obtained in the same manner as in Example 3 except that the opaque covering sheet was not provided with the tint block pattern printing for preventing see-through.

Comparative Example 4 A pressure-sensitive recording sheet was obtained in the same manner as in Example 4 except that the opaque coated sheet was not provided with the tint block printing for preventing see-through.

Comparative Example 5 A pressure-sensitive recording sheet was obtained in the same manner as in Example 5 except that the opaque covering sheet was not provided with the tint block printing for preventing see-through.

Test: Examples 1 to 4 and Comparative Examples 1 to 4
The pressure-sensitive recording sheet obtained in 1. was evaluated as follows.

Peelability: Examples 1 to 4 and Comparative Examples 1 to 1
With respect to the pressure-sensitive recording sheet obtained in No. 4, the opaque coating sheet was peeled off and the peelability was evaluated. All peeling occurred at the interface between the thermoplastic resin laminate layer and the tint block printing layer, or at the interface between the thermoplastic resin laminate layer and the opaque coating sheet, and the pressure-sensitive recording layer was peeled while being bonded to the thermoplastic resin laminate layer. The opaque cover sheet at one end of the sample opaque cover sheet was cut, and the opaque cover sheet was peeled from the thermoplastic resin laminate layer for evaluation. When the opaque coating sheet can be easily peeled off, the opaque coating sheet can be peeled off, but the peeling is a little heavy and the color develops on the pressure-sensitive recording layer. The case where the peeling was so heavy that the sheet was destroyed was judged as poor.

Adhesiveness: Examples 1 to 4 and Comparative Examples 1 to 1
In the pressure-sensitive recording sheet obtained in 4, the opaque coating sheet adheres to the pressure-sensitive recording sheet, and the opaque coating sheet is easily peeled off when the opaque coating sheet has sufficient adhesiveness to withstand the processes of mailing, cutting and printing. The product that was stored was judged to have poor adhesion.

Anti-Fluoroscopicity: When the contents of the pressure-sensitive recording sheets obtained in Examples 1 to 4 and Comparative Examples 1 to 4 are not readable when viewed through the watermark, the anti-fluoroscopic property is good, and the readableness is readable. Was judged to be inferior in the transparency prevention property.

Color development: Examples 1 to 4 and Comparative Examples 1 to
The pressure-sensitive recording sheet obtained in No. 4 was printed on the opaque coating sheet with an impact printer, and the opaque coating sheet was peeled off to confirm the coloring property. Color development was judged to be excellent in color development without any trouble in discrimination of recorded content, and poor color development was judged to be difficult to read recorded content.

[0052]

[Table 1]

Evaluation: Each of the pressure-sensitive recording sheets obtained in the examples had good internal recording when the opaque coating sheet was peeled off, and the internal print content was readable even when viewed through a watermark. could not. In the case of the pressure-sensitive recording sheet used in Comparative Example, the internal recording is good when the opaque coating sheet is peeled off in any case, but the internal print content is legible when seen through a watermark. It was necessary to print a background pattern on the surface of the pressure-sensitive recording sheet to prevent see-through in order to hide it. This is to limit the printing area on the surface, which is not preferable as a recording material or aesthetically.

[0054]

In the pressure-sensitive recording sheet of the present invention, the pressure-sensitive recording layer and the opaque coating sheet are integrated by the thermoplastic resin laminate layer, and the opaque coating sheet is lightly pressed to the thermoplastic resin laminate layer and the pressure-sensitive recording sheet. It can be separated (peeled) from the support having a layer. The pressure-sensitive recorded information can be handled without being exposed to the outside and exposed, and the opaque coating sheet can be peeled off as necessary to read the pressure-sensitive recorded information inside. Since the inner surface of the opaque cover sheet has a tint block print for preventing see-through, the contents cannot be deciphered even after watermarking after impact printing. Further, since the surface of the pressure-sensitive recording sheet does not have the tint block printing layer, the recording area can be increased. Information that has been disclosed once has the characteristic that it cannot be hidden again (re-adhesion-preventing property), and is used for many applications such as continuous slips, pasting slips, labels, postcards, and other correspondence, recording, dust-free recording paper, etc. It is of great practical significance to be able to stay.

[Brief description of drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Opaque coating sheet 2 Background pattern printing layer for see-through prevention 3 Thermoplastic resin laminating layer 4 Pressure sensitive recording layer 5 Support 6 Opaque coating sheet with background pattern printing 7 Pressure sensitive recording sheet

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Ninohira 34-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Paper Mills, Ltd.

Claims (4)

[Claims] 1. A pressure-sensitive recording layer in which a color-developing agent or a color-developing agent, both or one of which is microencapsulated, is singly laminated or mixed on one surface of a support, and a thermoplastic resin. An opaque coating sheet provided with a tint block print on one surface in contact with the laminate layer is integrated via a thermoplastic resin laminate layer, and the thermoplastic resin laminate layer is strongly adhered to the pressure-sensitive recording layer side, A pressure-sensitive recording sheet characterized by being weakly adhered to the opaque cover sheet side. 2. The pressure-sensitive recording sheet according to claim 1, wherein in the pressure-sensitive recording sheet, a surface of the opaque coated sheet which is in contact with the thermoplastic resin laminate layer is subjected to a mold release treatment. 3. The pressure sensitive recording sheet according to claim 1, wherein a developer or a microcapsule thereof is coated on one surface of the opaque coating sheet which is not in contact with the thermoplastic resin laminate layer. Pressure recording sheet. 4. The pressure-sensitive recording sheet according to claim 1, wherein in the pressure-sensitive recording sheet, a heat-sensitive recording layer is coated on one surface of the opaque coating sheet which is not in contact with the thermoplastic resin laminate layer.