JPS6195986A - Diazo thermal recording material - Google Patents

Abstract

PURPOSE:To improve the head matching property of a thermal color-forming layer as well as the resistance to staining and separation by gate pass when a diazo thermal recording material is used as commutation ticket by providing a protective film of an alcohol-soluble nylon resin on the thermal color-forming layer. CONSTITUTION:A thermal color-forming layer consists of one or two or more multi-layers formed of such components as a diazo compound, a coupler, and a heat-meltable substance on a supporter. An undercoat resin layer is provided, as needed, between the supporter and the thermal color-forming layer. The nylon resin used has a melting point of 100 deg.C or higher usually, preferably 120 deg.C or higher and a soluble in such lower aliphatic alcohols as methanol, ethanol, propanol, etc., or also in mixed solvents containing small amounts of water, trichloroethylene, chloroform, carbon tetrachloride, phenol, etc., making the formation of the protective film of nylon resin easier. The protective film of a thickness of 1-10mum is formed on the thermal color-forming layer by coating and drying to obtain a product.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a heat-sensitive recording material, and more particularly to a fixable diazo heat-sensitive recording material.

[Prior art]

Conventionally, as heat-sensitive recording materials, there are those that produce heat-sensitive coloring by utilizing the reaction between organic metal salts and reducing agents, and those that produce heat-sensitive coloring by using the reaction between leuco dyes and acidic substances. ing. However, such heat-sensitive recording materials have the disadvantage that recorded images cannot be fixed because they are non-fixable. That is,
In the case of such a non-fixable heat-sensitive recording material, it is possible to perform recording again by performing another heating printing after performing recording once by heating printing.

Therefore, the heat-sensitive recording material described above has low reliability in recording because the information recorded thereon can be falsified later, and is used in fields where reliability is required, such as securities, gift certificates, admission tickets, etc. It could not be applied to recording the necessary matters for certificates, slips, etc. or creating them. In addition, in the case of such recording materials, the temperature is generally 70°C.
When exposed to the above environment, the entire surface becomes colored and the problem arises that the records become illegible. In particular, heat-sensitive recording materials that utilize the reaction between leuco dyes and acidic substances have the disadvantage that recorded information is erased when they come into contact with organic solvents or plasticizers in plastics. These drawbacks are due to the fact that these heat-sensitive recording materials are non-fixable.

On the other hand, so-called diazo-sensitive paper, which utilizes the reaction between a diazo compound and a coupler, is widely known as a fixable recording material. In this diazo photosensitive paper, by irradiating the unreacted diazo compound with light after image formation, it can be photodecomposed and fixed.

Heat-sensitive recording materials are also known in which the reaction between a diazo compound and a coupler is caused by heating. This diazo-based heat-sensitive recording material has a heat-sensitive coloring layer containing a diazo compound and its coupler as the main reaction components on a support, and any one of the components in the heat-sensitive coloring layer is mixed with other components as discontinuous particles. The color reaction is prevented from proceeding by separating it from the other components.

Recently, heat-sensitive recording materials have become suitable for use as output recording materials for facsimiles, telex machines, electronic computers, medical measuring machines, ticket vending machines for one commuter pass, etc.
There is a strong demand for high-speed recording performance. In particular, in the field of ticket paper such as commuter passes and train tickets, there is a demand for heat-sensitive recording materials that can print at high speed and are capable of fixing in order to save labor and reduce expenses associated with fare revisions. Diazo-based heat-sensitive recording materials have the advantage of being fixable, but when applied to such applications, conventional materials have insufficient matching properties for thermal heads or gate path matching properties for commuter pass applications. It has some drawbacks.

〔the purpose〕

Unlike conventionally developed diazo-based thermosensitive recording materials, the present invention has sufficient thermal response for high-speed recording, good head matching performance for thermal heads (no sticking or head dregs), and can be used at automatic ticket gates. An object of the present invention is to provide a diazo-based heat-sensitive recording material that is free from staining and peeling due to geist passes and has excellent long-term storage stability.

〔composition〕

According to the present invention, in a heat-sensitive recording material in which a heat-sensitive color forming layer containing a diazo compound, a coupler, a thermofusible substance, and a binder is provided on a support, an alcohol-soluble nylon resin is provided on the heat-sensitive color forming layer. A diazo-based heat-sensitive recording material is provided, which is characterized by being provided with a protective film.

The present invention is particularly aimed at improving head matching properties and staining and peeling caused by gate passes when diazo thermosensitive recording materials are used for commuter passes.

When a thermofusible substance is included to satisfy thermal responsiveness, staking, image bleeding, trailing, etc. are likely to occur, and the surface is likely to be stained and peeled off when gate-passed. It has been found that providing a protective coating of alcohol-soluble nylon resin on the heat-sensitive coloring layer is effective in improving head matching properties and surface durability.

In addition, the heat-sensitive color forming layer as used in the present invention is composed of one layer or a multilayer of two or more layers formed to support heat-sensitive color forming layer forming components such as a diazo compound, a coupler, and a thermofusible substance on a support. This means the entire coating layer. Therefore, the components forming the thermosensitive coloring layer may be contained simultaneously in one coating layer, or may be appropriately divided into two or more layers. jf! 1. Contained in the fabric layer. Furthermore, in the case of the present invention, a resin subbing layer can be provided between the support and the heat-sensitive coloring layer, if necessary.

The nylon resin used in the present invention may be alcohol-soluble, and its melting point is usually 100°C or higher, preferably 120°C or higher.The nylon resin used in the present invention may be methanol or ethanol.

It is soluble in propatool and other lower aliphatic alcohols, and is also soluble in mixed solvents prepared by adding a small amount of water, trichlene, chloroform, carbon tetrachloride, phenol, etc. to these alcohols. Formation of a protective coating of nylon resin is easy. The thickness of the protective layer is about 1 to 10 μm.

Next, the basic thermosensitive color forming layer forming material used in the present invention will be explained in detail.

The diazo compound and coupler used in the present invention are those commonly used in diazo photosensitive paper, and examples thereof include those shown below.

Diazo compound: The diazo compound used in the present invention includes:

Conventional formulas 1 For example, those represented by the following general formulas are used.However, in general formulas (13, (II) and (III)).

R,, R6, R6 are hydrogen, halogen, 01-C5 alkyl group or alkoxyl group, or R12: Same as R2), R2, R3 are hydrogen, halogen, C□-C5 alkyl group or alkoxyl group.

R4 and R5 are the same or different 01 to C5 alkyl group, hydroxyalkyl group, alkyl group or alkoxyl group, or halogen) R7
is hydrogen, halogen, or trifluoromethyl group.

Mo, 82, and N3 are acid residues or acid residues forming a double salt with a metal salt. In this case, the acid residues include halogen ions and IIF4. Preferably, it is a fluorine-containing inorganic acid ion such as I) F, while metal salts that form double salts with respect to acid residues include 1, for example, ZncQ 2 , Cd
Examples include CQ 2.5nCI22. Y represents -CH2- or -CO-, and n is 0 or l.

Specific examples of things that fall under the general formula [■] are:

For example, the following can be mentioned:

A specific example of something that corresponds to general formula (1) is:

For example, one can cite the first-order one.

In the present invention, in order to obtain a product with further improved long-term shelf life, it is advantageous to use the diazo compound in the form of a water-insoluble salt such as a fluorate-containing salt such as -BF4 or -PF6.

Katsupura m: Couplers used in the present invention include phenol, resorcin, methylresorcin, phloroglucin, resorcinic acid, phloroglucinic acid, 2-methyl-5-methoxy-
1,3-dihydroxybenzene, 5-methoxy-1,3
-dihydroxybenzene, 4-N.

N-dimethylaminophenol, 2,6-dimethyl-1
．． 3. Phenol derivatives such as 5-trihydroxybenzene, 2,6-dihydroxybenzoic acid, 2,6-cyhydroxy-3,5-dibromo-4-methoxybenzoic acid, α
-Naphthol, β-naphthol, 4-methoxy-1-naphthol, 2,3-dihydroxynaphthalene, 2,3-
Sodium dihydroxynaphthalene-6-sulfonate, 2-
Hydroxy-3-propylmorpholinonaphthoic acid, 2-
Examples include naphthol derivatives such as hydroxy-3-naphtho-〇-1-luidite and 2-hydroxy-3-naphthoic acid morpholinopropylamide, but are not limited to these, and include diazo compounds. On the other hand, those that can act as couplers can be arbitrarily applied.

Thermofusible substances: Examples of thermofusible substances include the following.

Alcohol derivatives such as 2-tribromoethanol, 2,2-dimethyltrimethylene glycol, 1,2-cyclohexanediol, acid derivatives such as malonic acid, glutaric acid, maleic acid, methylmaleic acid, and animals such as beeswax and shellac wax. Waxes, vegetable waxes such as carnauba wax, 1V mineral waxes such as montan wax, petroleum waxes such as paraffin wax and microcrystalline wax, and other synthetic waxes such as polyhydric alcohol esters of higher fatty acids, higher amines, higher Amides, condensates of fatty acids and amines, condensates of aromatics and amines, synthetic paraffins, chlorinated paraffins, metal salts of higher fatty acids, higher linear glycols, dialkyl 3,4-epoxyhexahydrophthalates, N-alkyl Carbamoylbenzene etc.

The thermofusible substance used in the present invention preferably has a melting point or softening point in the range of 50 to 250°C.

If the melting point or softening point is less than 50°C, the shelf life of the product tends to deteriorate, and if it exceeds 250°C, the thermal response of the product to the thermal head becomes unsatisfactory.

In addition, from the viewpoint of obtaining a product with high-speed coloring property (high-speed recording property), these thermofusible substances used in the present invention should be used in an amount of 2 to 30 parts by weight, preferably 5 to 1 part by weight, per 1 part by weight of the diazo compound.
It is used in a proportion of 0 parts by weight. If this amount is less than the above range, color development will be insufficient and the resulting product will be unsuitable as a recording material for high-speed recording.

In the case of the present invention, it is particularly preferable to use 5 parts by weight or more for high-speed output recording such as facsimile.

On the other hand, if the amount added is too large, blurring of the image may occur during color development by heating, which is undesirable. Therefore, in the case of the present invention, the amount of the thermofusible substance added is preferably kept within the specified range.

In the present invention, a binding agent is used in order to firmly support the heat-sensitive coloring layer on the support.

Examples of such devices include the following.

Polyvinyl acetate, polyvinyl chloride, vinyl chloride/vinyl acetate copolymer, polyacrylic ester, polystyrene, polybutadiene, polyacrylamide, styrene/butadiene, acrylic copolymer, petroleum resin, polyvinyl alcohol, polyacrylamide, casein, Gelatin, starch and its derivatives, polyvinyl alcohol, carboxymethylcellulose, methylcellulose, ethylcellulose, polyester, polystyrene, chlorinated rubber,
Water-soluble, organic solvent-soluble, such as styrene-maleic anhydride copolymer, styrene-vinyltoluene copolymer, rosin modified resin, iso(or diiso)butylene-maleic anhydride copolymer, phenol resin, melamine resin, or Aqueous dispersion resin.

The binder used in the present invention has a melting point or softening point of 50
It is preferable to use one having a temperature of 250° C. to 250° C. from the viewpoint of obtaining a product with rapid color development. Further, the binders described above can be used alone or in the form of a mixture.

Further, in the present invention, the heat-sensitive coloring layer may further contain acidic substances, basic substances, fillers, and other substances as auxiliary components, if necessary.

Acidic substance: An acidic substance is added as necessary to prevent a coupling reaction and for storage stability, and includes, for example, the following.

Tartaric acid, citric acid, boric acid, lactic acid, gluconic acid.

such as sulfuric acid.

Basic substance'gt: A basic substance is added as necessary to cause a coupling reaction during heating, and examples thereof include the following.

Caustic alkalis and alkali carbonates such as sodium hydroxide, calcium hydroxide, and potassium carbonate.

Substances that generate basicity when heated include urea, thiourea and their derivatives, alkali salts of 1-lichloroacetic acid, ammonium chloride, ammonium sulfate, and ammonium citrate.

Filler: A filler is added to improve the matching property to a thermal head when heating is performed by a thermal head, and examples of such fillers include the following.

Organic and inorganic solid particles such as styrene resin fine particles, urea-formalin condensed metal fat particles, aluminum hydroxide, magnesium hydroxide, calcium carbonate, titanium, talc, kaolin, silica, and alumina.

As other auxiliary ingredients, zinc chloride, zinc sulfate, sodium citrate, guanidine sulfate, calcium gluconate, sorbitol, saccharose, etc. are used to suppress or assist color development.

In addition, the above-mentioned auxiliary components can be added to the protective film as necessary.6 To obtain the heat-sensitive recording material according to the present invention, the above-mentioned layer-forming components are dissolved or dispersed in an appropriate solvent to form each layer. A coating solution is prepared, and the coating solution is applied onto each support and dried. In this case, the solvent for dissolving or dispersing the layer-forming components is appropriately selected depending on the properties of the layer to be formed and the purpose of formation.

Such solvents include water or an aqueous solvent in which an organic solvent is dissolved in water, benzene, toluene, xylene, n-hexane, n-hebutane, cyclohexane, kerosene, methyl isobutyl ketone, methyl cellosolve, acetone,
Examples include nonpolar or polar organic solvents such as methyl ethyl ketone, dimethyl ether, and siloxane.

Furthermore, in the present invention, a subbing layer or an adhesive layer may be provided between the support and the heat-sensitive coloring layer, if necessary. In this case, both thermoplastic and thermosetting resins can be used as the resin constituting the adhesive layer. Thermoplastic resins include polyolefins, polyvinyl compounds, saturated polyester resins, polyurethanes, polyamides, etc., and thermosetting resins include phenolic resins, urea resins, melamine resins, alkyd resins, unsaturated polyester resins, epoxy resins, etc. can be mentioned.

Next, a protective film of the present invention is applied to a thickness of 1-io μm on the heat-sensitive coloring layer formed as described above,
Dry and use as a product.

The heat-sensitive recording material of the present invention can be advantageously applied in various fields of heat-sensitive recording, particularly as ticket paper for commuter passes and train tickets that require high-speed recording, and in the case of the present invention, the surface Characters and images recorded on the film can be fixed by forming the image by heating and then decomposing the unreacted diazo compound with light. Further, the heat-sensitive recording material of the present invention can be used to record securities, gift certificates, etc. by utilizing its fixing properties.
Recording of necessary information for admission tickets, certificates, slips, etc.
It can be applied to their creation.

〔effect〕

By providing a protective coating of alcohol-soluble nylon resin on the thermosensitive coloring layer, a thermosensitive recording material can be obtained which has excellent matching properties to thermal heads and surface durability during gate passes, and also has good thermal responsiveness.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples. In addition, the parts and percentages shown below are all! This is R Seki City.

Examples [Liquid A] Nistearic acid amide 5 parts Polystyrene resin (molecular weight 3000, softening point 95°C) 3 parts Cyclohexane 90 parts The above composition was dispersed in a ball mill for 24 hours to prepare [Liquid A].

[Liquid B]: 2,6-cyhydroxy-3,4-dibromo-4-methoxybenzoic acid 5 parts Stearic acid amide 15 parts Polystyrene resin (molecular weight 2000, softening point 100°C) 3 parts n-hexane 73 parts Above composition was dispersed in a ball mill for 24 hours to prepare [Liquid B].

[Liquid C]: Prologlucin 5 parts N-octadecyl(4-methoxycarbonyl)benzamide
10 parts charcoal calcium
1 part sodium thiosulfate
1 part polyvinyl alcohol
20 parts water
63 parts of the above composition was dispersed in a ball mill for 24 hours to prepare + (Liquid C).

[Liquid D]: Unsaturated polyester resin 20 parts toluene/methyl ethyl ketone (mixing ratio 1/I) 80
(Liquid D) was prepared by dissolving the two-part composition.

[E liquid]

Alcohol iiJ soluble nylon resin 10 parts [
Manufactured by Toshina, CM-8000) Ethanol 70 parts Water

20 parts of this composition was stirred to prepare [Liquid E].

Guest performance (Al-([) with the combination shown in Table 1, thickness 187μ
A diazo thermosensitive recording material was prepared by coating the mixture onto a polyester film support and drying. Regarding the adhesion amount of guest performers, CD liquid] is 5 to 1Oμta-A, B, C
The liquid is 0.5-3.0g/m (solid content), and the E liquid is 3.
~57za+ closed.

Table 1 * Comparative example The recording materials obtained as described above were printed in G-I11 mode using a Rifax 303 (manufactured by Ricoh), and then completely printed using a Ricopy High Start model 4 (manufactured by Ricoh). Those that have been exposed to light and fixed do not develop color even when heated.
The image did not disappear due to organic solvents.

Next, a color density test was conducted on the diazo thermosensitive recording material obtained above. The results are shown in Table-2. The solid print density in the G-m mode of the color density gauge Fax 303 was measured using a Macbeth densitometer (RD-514). In addition, in order to test head matching performance, the occurrence of sticking during printing was investigated using the Refax 303 in G-111 mode. Furthermore, we conducted gate pass tests at automatic ticket gates 1,000 times. The results are also shown in Table 2.

Table 2 * Comparative example [Gate pass property] 0: No problem x: Problem within soo times (occurrence of dirt and scratches)
It is clear from Table 2 that the diazo thermosensitive recording material of the present invention has excellent head matching properties and gate pass properties without reducing color density.

Claims (1)

[Claims] (1) In a heat-sensitive recording material in which a heat-sensitive coloring layer containing a diazo compound, a coupler, a thermofusible substance, and a binder is provided on a support, a protective film of an alcohol-soluble nylon resin is provided on the heat-sensitive coloring layer. A diazo-based heat-sensitive recording material characterized by: