JP2935154B2 - Thermal recording paper for outdoor meter reading - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosensitive recording medium capable of recording an image by a thermosensitive recording system.

[0002]

2. Description of the Related Art A thermosensitive recording medium generally comprises a base and a thermosensitive recording layer formed on the base, and is heated by a heat head, a hot pen, a laser beam or the like to form a coloring agent in the thermosensitive recording layer. Reacts instantaneously to form a recorded image (for example, Japanese Patent Publication No. 43-4160, Japanese Patent Publication No. 45-140).
No. 39).

[0003] Such a thermosensitive recording medium can obtain a recorded image by a relatively simple device, and is easy to maintain.
In addition, since it has advantages such as no noise, it is used in a wide range of fields such as a measuring recorder, a facsimile, a printer, a computer terminal, a label, and an automatic ticket vending machine such as a ticket.

[0004] In recent years, in particular, there has been a remarkable expansion of applications to ATMs for banks, meter readings for gas and electricity, etc., and due to these, characteristics that have not been a problem in the past have been required.
The improvement is required.

That is, naturally, demands for performance such as fading of an image such as weather resistance and chemical resistance and fogging of the background are required. When used for gas and electricity meter reading, it is used outdoors and in the rain. Sometimes.

In this case, when the thermal paper after recording is wet with water, there arises a problem that the thermal recording surface and its back surface or the thermal recording surface adhere to each other to make it impossible to read the recorded image, or the winding before recording is performed. Water droplets fall on the side surfaces, blocking the heat-sensitive recording surface and the back surface, resulting in problems such as poor recording paper feeding.

This is because the binder generally used for the thermal paper is a water-soluble resin or a synthetic resin emulsion, which becomes tacky when wet.

In order to solve this problem, it is conceivable to increase the water resistance of the binder used in the thermal paper by using a crosslinking agent, but it is not possible to apply sufficient heat to the crosslinking reaction during the production of the thermal paper. In addition, there is a problem specific to the thermal paper that the thermal paper develops a color when a highly reactive crosslinking agent is used.

In consideration of only water resistance, it is sufficient to use no water-soluble resin or synthetic resin emulsion as a binder in the production of thermal paper. However, a binder instead of these should be used from the viewpoint of economy and heat resistance. Very difficult.

On the other hand, in the case of a thermosensitive recording medium for a handy terminal such as an ATM for a bank, a gas meter, and an electric meter, it is necessary to previously print a frame for a recording column, an issuer name and various information on a thermosensitive recording surface. However, depending on the printing ink used, these may be deposited on the thermal head when the printer is used for a long period of time and may cause significant printing trouble.

[0011]

SUMMARY OF THE INVENTION The present invention provides a high-water-resistance thermosensitive recording for outdoor meter reading which does not cause a problem such as blocking even when used outdoors and does not cause printing trouble.
It was intended to provide paper .

[0012]

Means for Solving the Problems A thermosensitive coloring layer containing a thermosensitive coloring component is provided on the surface of a support made of paper, and the thermosensitive coloring layer is provided.
Water-soluble polymer and glyoxal as main components on the color layer
The above-mentioned problem has been solved by providing a protective layer, printing a desired pattern on the protective layer with a printing ink, and further providing an ultraviolet curable resin layer on the entire surface.

The UV-curable resin layer is described in detail in publications such as “Taiseisha: Light / Radiation Curing Technology”. However, in brief, photopolymerizable monomers, prepolymers or polymers are described. It is obtained by polymerizing by irradiating an ultraviolet ray to an ultraviolet curable resin composition containing a photopolymerization initiator as an essential component.

The monomer and the prepolymer or polymer have compatibility and are copolymerizable.

As the prepolymer, unsaturated polyester, epoxy, acrylic, various polyesters and the like can be used, and as the monomer, various ethylene derivatives can be mentioned.

After a desired pattern is printed on the thermosensitive coloring layer or the protective layer with a printing ink, it can be provided on the entire surface by a coating method or a printing method.

The ultraviolet-curable resin layer has a thickness of 0.1 to 10 g / m.
2 Preferably, it is provided at 0.5 to 6 g / m2.

Printing inks are described in detail in publications such as "Printing Ink Technology" published by CMC Co., Ltd., and include inks such as penetrating drying, evaporative drying, oxidative polymerization drying, and photopolymerization drying (ultraviolet curing type) inks. A conventionally known ink is used.

The coloring system used for the heat-sensitive layer may be any one which satisfies the object of the present invention, for example, a coloring system obtained by reacting a leuco dye with an electron accepting substance represented by a phenolic substance, an imino compound and an isocyanate. Any of those based on the reaction with the compound and those based on the reaction between the long-chain fatty acid iron salt and the polyhydric phenol may be used.

In the present invention, it is preferable to provide a protective layer mainly composed of a water-soluble polymer and / or a synthetic resin emulsion on the thermosensitive coloring layer.

In the present invention, a protective layer mainly composed of a water-soluble polymer and / or a synthetic resin emulsion is provided on the thermosensitive coloring layer .

When a protective layer containing a water-soluble polymer and / or a synthetic resin emulsion as a main component is provided on the thermosensitive coloring layer, the above-mentioned water-soluble binder can be used to increase the water resistance of the film. Therefore, various crosslinking agents can be used.

Further, the following chemicals are added to the heat-sensitive layer and / or the protective layer and / or the ultraviolet curable resin layer according to the purpose.

As the pigment, diatomaceous earth, talc, kaolin, calcined kaolin, calcium carbonate, magnesium carbonate, titanium oxide, zinc oxide, silicon oxide, aluminum hydroxide, urea-formalin resin and the like are used.

In addition, for the purpose of preventing head abrasion and sticking, higher fatty acid metal salts such as zinc stearate and calcium stearate, and waxes such as paraffin, paraffin oxide, polyethylene, polyethylene oxide, stearic amide, caster wax and the like are used. ,Also,
Various oxalates such as metatarphenyl, parabenzylbisphenyl, esters of hydroxynaphthoic acid, stearamide, tribenzylamine, naphthalene derivatives, dibenzyl terephthalate, dibenzyl oxalate, and bis (paramethylbenzyl) oxalate as sensitivity enhancers Etc. can be used.

Further, a dispersant such as dioctyl sodium sulfosuccinate or the like, a surfactant, a fluorescent dye and the like are used as required.

As the substrate in the heat-sensitive recording material of the present invention, paper is mainly used, but various nonwoven fabrics, plastic films, synthetic papers, metal foils and the like, or composite sheets combining these can also be used. If necessary, an undercoat layer may be provided between the substrate and the heat-sensitive recording layer.

It is also conceivable to print a desired pattern with a printing ink after providing an ultraviolet curable resin layer on the thermosensitive coloring layer or the protective layer, but it is effective for blocking when wet with water. However, because the adhesion between the UV-curable resin layer and the printing ink is not good, the printing ink accumulates on the thermal head when the printer is used for a long period of time, causing troubles that cause important printing troubles.
Not preferred.

Hereinafter, the present invention will be described more specifically with reference to Examples, but it should not be construed that the invention is limited thereto. In the examples, “parts” and “%” indicate “parts by weight” and “% by weight”, respectively, unless otherwise specified.

Example 1 and Comparative Example 1 Preparation of Solution A 3-Di-butylamino-6-methyl-7-anilinofluoran 10 parts 20% polyvinyl alcohol (Kuraray Povar 105, manufactured by Kuraray) 10 parts Water 20 parts The composition was pulverized with a sand mill until the average particle diameter became 0.8 μm.

Solution B 4,4'-Diisopropylidene diphenol 10 parts 20% polyvinyl alcohol (Kuraray Povar 105, manufactured by Kuraray) 10 parts Water 20 parts This composition is sand-milled to have an average particle diameter of 1.5 μm. Until ground.

Solution C Preparation Metaterphenyl 10 parts 20% polyvinyl alcohol (Kuraray Poval 105, manufactured by Kuraray) 10 parts Water 20 parts This composition was pulverized by a sand mill until the average particle diameter became 1.0 μm.

Formation of heat-sensitive recording layer 40 parts of solution A, 80 parts of solution B, 40 parts of solution C, 20% polyvinyl alcohol (Kuraray Povar 105, Kuraray) 60
And 50 parts of water were mixed and stirred to obtain a coating solution for a heat-sensitive recording layer.
The obtained coating solution was dried on a high-quality paper of 50 g / m 2 with a dry weight of 4
g / m 2 and dried.

Formation of protective layer 20% polyvinyl alcohol (Kurarepovar 105,
Kuraray 400 parts, silica (P-527 Mizusawa Chemical) 10 parts, 30% zinc stearate dispersion (D-52)
3 Chukyo Yushi) 30 parts, glyoxal 10 parts, water 2
00 parts were mixed and stirred to obtain a coating liquid for an overcoat layer.

The obtained coating solution was applied on the above-mentioned heat-sensitive recording layer so that the dry weight was 3 g / m 2 and dried.

Formation of Print Pattern A frame for a record column, the name of an issuer, and the like were printed on the protective layer by lithographic offset printing using an oxidatively polymerized and dried ink.

Formation of UV Curable Resin Layer An ultraviolet curable resin (Dicure ROP varnish manufactured by Dainippon Ink) was printed over the entire surface of the layer on which the print pattern was formed using a lithographic offset printing machine at about 1 g / m 2. Thereafter, the recording material was cured by an ultraviolet irradiation device to obtain a recording medium of the present invention.

The case where the UV-curable resin layer was formed is referred to as Example 1, and the case where the UV-curable resin layer is not formed is referred to as Comparative Example 1.

[0039]

[0040]

[0041]

[0042]

Blocking Test 1 After a water drop was dropped on the recording surface of the heat-sensitive recording medium after recording, the recording surface of another heat-sensitive recording medium was superimposed, and then a load of 100 g / m 2 was applied to the room at 20 ° C. and 65% RH. After 24 hours, both were peeled off and the degree of blocking was evaluated. ○ was evaluated as no blocking, X was evaluated as blocking occurred and a part of the recording layer was broken, making it difficult to read the record, and XX was evaluated as blocking was severe and the recording paper was broken.

Blocking Test 2 After a water drop was dropped on the recording surface of the heat-sensitive recording medium after recording, the back surface of another heat-sensitive recording medium was overlaid, and then a load of 100 g / m 2 was applied to the recording medium at room temperature of 20 ° C. and 65% RH. After standing for 24 hours, both were peeled off and the degree of blocking was evaluated.は: No blocking, X: Blocking occurred, a part of the recording layer was broken, and it was difficult to read the record. XX: Blocking was severe, and the recording paper was broken. Was evaluated.

Blocking Test 3 A drop of water was dropped on the wound end surface, left for 24 hours in a room at 20 ° C. and 65% RH, and then printed with a Canon Handy Terminal Printer HT9000 to test a running property.は was evaluated as good in runnability, △ as paper was conveyed, but slightly resistant and irregular in runnability, and x was evaluated as no paper being conveyed.

Printing Test Printing was performed continuously for 100 m using a Canon Handy Terminal Printer HT9000, and the presence or absence of a substance attached to the thermal head was examined. ○ indicates no adhesion and good printing. The symbol “Δ” indicates that there is no printing trouble although there is a little attached matter. In the case of x, the amount of attached matter was extremely large, and printing trouble occurred. And evaluated as above.

[0047]

[Table 1]

[0048]

As is clear from the results in Table 1, the thermal recording paper for outdoor meter reading obtained in the examples of the present invention has excellent heat resistance,
The printing characteristics were also good .

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideo Kamijo 1-330 Akabori, Okegawa City, Saitama Prefecture International Charter Engineering Center (56) References JP-A-3-293190 (JP, A) Kaihei 4-220390 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B41M 5/28-5/34

Claims (1)

(57) [Claims] A thermosensitive coloring layer containing a thermosensitive coloring component is provided on the surface of a paper support , and a water-soluble layer is formed on the thermosensitive coloring layer.
A protective layer mainly composed of a conductive polymer and glyoxal.
A thermosensitive recording paper for outdoor meter reading with high water resistance, characterized in that a desired pattern is printed on the protective layer with a printing ink and then an ultraviolet curable resin layer is further provided.