JPS6122986A - Diazo fixation type heat-sensitive recording body - Google Patents

Abstract

PURPOSE:To obtain a diazo fixation type heat-sensitive recording body which is highly sensitive and excellent in preservation and, in addition, with improved textile coloring by concurrently adding thiourea and metallic salt of acid to a diazo fixation type heat-sensitive recording body. CONSTITUTION:A diazonium salt, an acid which is precoupling inhibitor of coupling compounds and a photosensitive, heat-sensitive layer of which fine particle dispersed body of hydrophobic, organic, basic compound that indicates basic atmosphere when heated and fused constitutes the main compound as a developer are provided on a substrate, and into the above photosensitive, heat-sensitive, layer of diazo fixation type heat-sensitive type body thiourea is added for prevention of texture coloring. And concurrently with the addition of the thiourea, metallic salts of inorganic or organic acids that have dissociation constants that are either equal to or larger than those of acids as precoupling inhibitors are used. Thus, texture coloring after fixation may be improved without a decrease in preservation characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Technical Field of the Invention The present invention relates to a diazo-fixed heat-sensitive recording material, and more specifically, it relates to a diazo-fixed heat-sensitive recording material, and more specifically, a high-sensitivity recording material that has excellent storage stability and improved background coloring after fixing. This article relates to a diazo-fixed heat-sensitive recording medium.

(Prior art and points of interest) In recent years, high-speed printers, facsimiles, etc. have made remarkable progress in response to society's demand for outputting large amounts of information as hard copies as quickly as possible. As a method of forming an image on a recording medium according to electrical information, electrophotography 1. Electrostatic recording, discharge TD recording, inkjet recording, thermosensitive recording, etc. are known. Because it is relatively simple and the recording paper is also relatively cheap, it has become rapidly popular in recent years. One method of this thermal recording method uses a color-forming substance such as crystal violet lactone and bisphenol A. Heat-sensitive recording sheets made by combining such phenolic compounds are described in, for example, Japanese Patent Publication No. 14039/1982, and are already known. Widely used as recording paper for various recorders, electrocardiographs, calculators, heater terminals, facsimile machines, etc.

However, in the conventional method described above, if the back plate is heated incorrectly after printing, the backing becomes colored and becomes unreadable, and the OT function may be tampered with after printing, so improvements to these problems are strongly desired. There is.

The present inventors conducted research with the intention of providing a destructible heat-sensitive recording material that solved the problem of long life, and first developed a material that promotes the reaction between a diazonium salt and a coupler compound. It has already been discovered and proposed that by using guanidine M4 having a certain general formula, it is possible to provide a fixable heat-sensitive recording material with high sensitivity and excellent storage stability. (Unexamined Japanese Patent Publication No. 57-45094, No. 57-125091
However, depending on the diazonium salt used, the amount of oil applied, the composition of the coating liquid, etc., the active diazonium salt photodecomposed during the fixing process in which the diazonium salt is photodecomposed after heating printing may undergo various reactions such as self-coupling. As a result of this reaction, the background may be colored pink, and increasing the amount of acid, which is a pre-coupling inhibitor, to prevent this reaction will result in a decrease in color development sensitivity. Although it has some effect in preventing skin discoloration, increasing the amount added to improve the effect tends to lead to deterioration in storage stability.There has been a demand for improvement of these drawbacks.

OBJECT OF THE INVENTION An object of the present invention is to overcome the above-mentioned drawbacks and provide a diazo-fixed heat-sensitive recording material which has a high sensitivity of 1 t, has excellent storage stability, and has improved background coloring after fixing.

(2) Structure and operation of the invention The present invention is a fine particle dispersion of a diazonium salt, an acid which is a coupler compound pre-coupling inhibitor, and a hydrophobic organic basic compound which is melted by heat and exhibits a basic atmosphere as a color developer. In the diazo N-type heat-sensitive recording material, which has a photosensitive and heat-sensitive layer formed on a support, the photosensitive and heat-sensitive layer contains thiourea and a dissociation constant equal to or larger than that of the above-mentioned acid. ◎ The acid as a pre-coupling inhibitor used in the present invention can be used in conventionally known diazo type copying materials. Any organic or inorganic acid compound can be used; specific examples include tartaric acid, citric acid, boric acid, lactic acid, gluconic acid, phosphoric acid,
Trichloroacetic acid, dichloroacetic acid, cyanoacetic acid, Scheric acid, malonic acid, maleic acid, etc. are all preferably used. ◎The weight ratio of these acid compounds to the organic basic compound is 1.0% or more. It is preferably used within a range of 30%, more preferably within a range of 5 to 15%.

In addition, the thiourea used for the purpose of preventing skin discoloration in the present invention is 0.
．． 117m” ~ 1. OI 7m” (used in D range,
6 is preferable, and if it is less than 0.1117 m, there is no effect of preventing background coloring, and if it is more than 1097 m'', the storage stability of the diazo-fixed thermosensitive recording material will be deteriorated.

Therefore, although there is a natural limit to the amount of thiourea added, it is recommended to use a metal salt of an inorganic or organic acid with a dissociation constant equal to or larger than that of the acid as a pre-coupling inhibitor. It is possible to improve the coloration of the skin after deposition without deteriorating the storage stability. If you deviate from this condition and use gold Ji4 salt, an acid with a smaller dissociation constant than the acid as a pre-coupling inhibitor, the storage stability will be improved. This will lead to deterioration in storage stability. For example, when 1 g of citric acid is added to a citric acid water bath solution, a chemical reaction occurs when 1 g of nitric acid (an acid with a small constant, zinc acetate) is added, and citric acid is produced, and #acid is liberated. Therefore, since the acetic acid is very unstable at room temperature, it gradually evaporates, causing pre-coupling and deterioration of storage stability. The striped salt can be added and applied by dissolving the soluble one in the solvent and dispersing the insoluble one.◇The effects of the present invention can be applied not only to hydrophobic guanidine derivatives but also to widely known organic bases. It is also observed when the compound is used as a color developer, but %
Preferred organic basic compounds include the following general formula (!):
Diazo fixing plate/ii with high sensitivity and excellent storage stability when used in combination with the guanidine fermentation conductor of general formula (6)
% heat record is obtained.

General formula (1) General formula (2)
Represents the following alkyl, cyclic alkyl, aryl, aralkyl, amine, alkylnamino, 7-cylamino, carbamoylamino, multi-chord *aa, where aryl & in the formula represents lower alkyl, alkoxy, nitro, acylamino, alkylamino group and those having a substituent selected from halogen are also included. ] As the diazonium salt used in the present invention, any compound used in conventionally known diazo type copying materials can be used, for example, the following compounds! Specific examples that can be suitably used for Benzenediazonium chloride, 2,5-jethoxy-4-N,N-diethylaminobenzenediazonium chloride IJI', 4-
N-ethyl-N-hydroxyethylaminobenzenediazonium chloride, 4-N.

N-diethylaminobenzenediazonium chloride, 4
-phenylaminobenzenediazonium chloride, 4-
N-(P-methoxyphenyl)-7minobenzenediazonium chloride, 4-morpholinobenzenediazonium chloride, 2,5-jethoxy-4-morpholinobenzenediazo;um chloride, 4-oxacyridinobenzenediazonium chloride, 3-methyl-4-piperidinobenzenediazonium chloride, 4-ethylcapto-2,5-ethoxybenzenediazonium chloride,
4-Tolylmercapto-2,5-jethoxybenzenediazonium chloride, 4-penzylmercapto2.
Examples include 5-dimethoxybenzenediazonium chloride.

Further, as the coupler compound which reacts with the diazonium salt to form an azo dye, any compound capable of coupling with the above-mentioned diazonium salt can be used. Examples of these coupler compounds include phenol derivatives and oxynaphthalene derivatives, and examples of compounds containing active methylene groups include the following yl compounds.

(1) Phenol derivative Pyrocatechol resorcin Phloroglycine Pyrogallol meta-aminophenol para-aminophenol diethylaminophenol N-7 uri-para-aminophenol R-acyl-meta-aminophenol 31 31.5 - IJ hydroxydiphenyl 3
．． 3',5,5'-tetrahydroxydiphenyl α-
Resorcinol! -Resorcinic acid r-Resorcinic acid 70 Loglucincarboxylic acid Gallic acid Diresorcin sulfide Diresorcin sulfoxide 3.5-Resorcinic acid ethanolamide Fe2. 4-Resorcinic acid ethanolamide 4-Bromresorcin 4-Chlororesorcin 2-Methylresorcin 3. 3T~Butylene dioxydiphenol 3.3I-Ethylenediochimidiphenol bisphenol A (2) Oxynaphthalene derivative 2 + 3- V hydroxynaphthalene β-naphthol a-naphthol l, 6-dihydroxynaphthalene 2.3-dihydroxynaphthalene- 6-sulfonic acid 2-
Naphthol-3,6-disulfonate 1,8-dihydroxynaphthalene-8-sulfonic acid 2-hydroxy-3-naphthoic acid-N-β-hydroxyethyl-amide 2-hydroxy-3-naphthoic acid-N,N- β-hydroxyethylamide 5-(paranitro)-benzamide-1-naphthol 1
-Naphthol-3-('N-β-hydroxyethyl)-
Sulfone-amide 2-hydroxy-3-propylmorpholinonaphthoic acid 2
-Hydroxy-3-naphtho-0-toluicide 2-hydroxy-3-7toic acid sorifolinoglopyramide 2-hydroxy-3-naphthoic acid m-4'-chloroanilide 2-hydroxy-3-naphthoic acid (W- 5'-chloro-
21゜4+-di-methoxyanilide 2-hydroxy-3-naphthoic acid hN, 2+, 5''-dimethoxyanilide 2-hydroxy-3-naphthoic acid -2-ethoxyanilide 2-hydroxy-3-naphthoic acid-2'- Methoxyanilide 2-hydroxy-3 ninaphthoxylic acid phenyl ester.

2-hydroxy-3-naphthoic acid-4-phenoxyanilide 2-hydroxy-3-naphthoic acid-4-pendeloxyanilide 2-hydroxy-3-naphthoic acid-4-phenethyloxyanilide 2-hydroxy-3-naphtho-4
-2'-pendeloxyanilide 2-hydroxy-3
-Naphthoic acid-2'-dimethylanilide 2-hydroxy-3-naphthoic acid-4-methoxyanilide (3) -Compound containing active mebulene group 1-phenyl-3-methyl-hyrasolone (5) Acetoacetic acid Anilide 1-phenyl-3-carboxypyrazolone acetoacetic acid cyclohexylamide acetoacetic acid Benziamide cyanoacetanilide cyanoacetomorpholine 4-carbogycyacetonacetanilide These coupler compounds can be processed using a ball mill, sand grinder, attritor, etc. It can be contained in the light and heat sensitive layer as a fine particulate dispersion with a particle size of 10 μm or less using the following dispersion means.

Moreover, the number of coupler compounds is 1 type or 2a! The above may be combined to produce a dye exhibiting a desired spectral absorption viscosity.

In addition, during dispersion, the coupler compound may be dispersed alone, but it can also be co-dispersed with an organic basic compound or other additives if necessary. If it is soluble in water, which is used as a solvent for the coating solution when applied to the surface, the pH of the coating solution will increase, causing capri of the scalp and deterioration of storage stability. It is desirable to exist as
If the solubility in water at 20°C is below LOII/no, it has good humidity and heat storage stability, and is suitable for complex compounds such as aliphatic amines, pyrrolidine g4, imidazole 94, imidacillin derivatives, piperidine tj2+, etc. In particular, when hydrophobic guanidine derivatives of the following general formulas (I> and (B)) are used as color developers, they have excellent storage stability under high temperature and high humidity conditions, and have high sensitivity. It is possible to obtain a diazo-fixed heat-sensitive recording material that develops color and has excellent image storage stability.Furthermore, a color developer having a melting point in the range of 100 to 170°C can be particularly preferably used. It may be dispersed alone using a dispersion means such as a sand grinder or an attritor, but it may also be co-dispersed with a coupler compound and other additives, if necessary.

Depending on the requirements, polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, sodium alginate, etc. may be added as a protective colloid agent in an amount of 0.5 to 10% of the solid content during dispersion.

Or, [in the formula, 凯FLl, B1, R4 and 结 are hydrogen, alkyl having 18 or less carbon atoms, cyclic alkyl, 71J −/
l/ represents an aralkyl, amine, alkylamino, acylamino, carbamoylamino, aSS residue, and the aryl group in the formula is a substituent selected from lower alkyl, alkoxy, nitro, acylamino, alkylamino groups, and 710 gen. ] - Typical specific examples thereof are shown in Table 1.

Oh.

No.

N.H. N.H. υHa OH@ N.H. NH,-0-NH,N NH, -0-NH.

NH, -0-NH.

(3B) (39)N
N These guanidine derivatives shown above can be easily synthesized by known methods or methods similar thereto.

The photosensitive and thermosensitive layer of the present invention mainly contains a diazonium salt, a coupler compound, an acid as a bleed-up inhibitor, a coloring agent, etc. However, these may be formed in a single layer by forming a photosensitive and thermosensitive layer on a support. However, the above main components may be divided into multiple layers and provided on the support. Also, as binder materials for forming the light and heat sensitive layer of the present invention, corn starch, gum arabic, glue, gelatin, etc. , casein, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, starch such as bo-1-noacrylamide, carboxymethyl starch, dialdehyde starch, or modified products and derivatives thereof, polyvinyl alcohol or modified products thereof, and ys4 form, polyvinylpyrrolidone, imbutylene - Maleic anhydride co-heavy metal, polyacrylate, styrene - iron maleate anhydride, polyvinyl chloride, polyvinylidene chloride, polystyrene, styrene-styrene-butadiene rubber (=88n), methacrylate-butadiene rubber (=MBR) , nitrile butadiene rubber (=NBR)
, polymethyl methacrylate, polypropylene, polyacrylonitrile, acrylic acid ester, and other synthetic resin emulsion resins. These binder materials can be used alone or in combination. The storage stability of fixed mg thermal recording materials using diazonium salts, especially under high temperature and high humidity conditions, is also greatly improved by selecting a binder material with a low equilibrium moisture content, since it is promoted under polar solvents.
In addition, storage stability can also be improved by using water-resistant agents that are normally used to remove water-soluble polymer binders, such as formalin, glyoxal, chromium alum, glucuraldehyde, melamine/Volf 9F fat, and urea/formalin resin. can be improved.

Specific examples of pigments used in the photosensitive and heat-sensitive layer of the present invention include kaolin, calcined kaolin, talc, waxite, diatomaceous earth, styrene sanitary particles, calcium carbonate, magnesium hydroxide, aluminum hydroxide, and magnesium carbonate. , titanium oxide, barium carbonate, urea-formalin filler, cellulose filler, aluminum oxide, etc., but from the viewpoint of thermal head matching properties such as scum and sticking, load amount 53-118059.54-258
45.54-118846.54-118847 Publication y mouth oil absorption is 80d~500g/100F oil absorption f! according to the measurement method specified in JI8 5101! It is desirable to use 4 types of pigments, especially in the layer that comes into direct contact with the thermal head, it is desirable to use oil-absorbing pigments that exhibit the above-mentioned oil absorption amount, such as calcined kaolin or urea-formalin fillers.Other auxiliary components If necessary, ultraviolet inhibitors and antioxidants may be added, and waxes and metal soaps may be used for the purpose of improving sticking and coloring sensitivity.

Specifically, waxes include paraffin wax, carnauba wax, microcrystalline wax, polyethylene wax, and -grade fatty acid amides such as stearic acid amide, lauryl amide, myristyl amide, hardened tallow acid amide, and valmitic acid amide. , oleic acid amide, acetamide, coconut fatty acid amide, or methylolated products of these fatty acid amides, methylene bis stearamide, ethylene bis stearamide, and -class fatty acid esters etc. 0 Metallic soaps include higher fatty acid polyhydric Metal salts, namely zinc stearate, aluminum stearate, f7! Examples include acid salts, oleic acid and zinc drinks.
□ Also, as a sensitizer to improve color development sensitivity, it has a melting point of 90℃~
It is also possible to use a substance that has good compatibility with organic basic compounds, turnip 2-compounds, etc. when heated at 150°C.

As these substances, any substance can be used as long as it has good compatibility during heating, but in particular - benzene fields in the molecule,
A substance having a naphthalene ring and also having a polar group such as an ether bond or a carbonyl group (ketone group, ester group) can be suitably used. Specific examples include dimethyl terephthalate, diindyl terephthalate, 1-methoxynaphthalene, 1,4-jethoxynaphthalene, and benzyl ether of P-hydroxybenz benzyl ester.

It can be used alone or dispersed, but it can also be used co-dispersed with an organic basic compound, a coupler compound, etc.

Further, a protective layer may be provided on the photosensitive and heat sensitive layer for the purpose of improving the water resistance, chemical resistance, and frost resistance of the painting.

In addition to paper, synthetic resin films, laminated paper, etc. can be used as the support. When paper is used as a support, if the photosensitive and heat-sensitive layer is applied directly onto the support, the diazonium salt will fill the voids in the paper base. Since a large amount of diazonium salt is required to penetrate and impregnate the inside, the sensitivity of light fixing due to exposure after thermal printing may decrease. The material is pre-coated with a void photoresist such as silica sol, alumina, titanium oxide, or kaolin, or a combination of these and a polymeric material such as starch, casein, polyvinyl alcohol, or polyvinyl acetate emulsion, and then a photosensitive and heat-sensitive layer is applied. It's okay.

(Odor) Examples Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Example 1 A photosensitive/thermal layer coating solution having the following composition is prepared in V#, coated on a support so that the coated amount after drying is 9.0117 mm, and dried to prepare a fixable heat-sensitive recording material. 0 unit is 'iIE
It is a department.

In addition, the mu liquid and 1% liquid are distributed as follows using a ball mill.
Example 2 of B solution prepared by time-grinding A diazo-fixed heat-sensitive recording material was prepared in the same manner as in Example 1 except that sodium seulfate was used instead of zinc siolate. 0 Example 3 A diazo-fixed heat-sensitive recording material was prepared in the same manner as in Example 1, except for using resin as the pre-coupling inhibitor in Example 1 and 2.90 Comparative Example 1 Example I Diazo fixing was carried out in the same manner as in Example 1 except that thiourea and zinc siolate were not added.

Create a type thermosensitive recording material and fc.

The thus obtained diazo-fixed heat-sensitive recording material was printed and recorded using a Fujitsu Facom Fax 6210, the diazonium salt was decomposed and fixed by full-surface ultraviolet exposure, and color development was performed using a Macbeth m difference meter (ILI). 514).

In addition, as a moisture and heat resistance test to evaluate storage stability,
The diazo-fixed heat-sensitive recording material prepared as described above was
The diazonium salt was photolyzed after being left at 90% for 244 minutes and the $Ig' of the scalp capri was measured in the same manner as above. The white KN measured at tffIJb was measured.

(Effect of the clever invention) By adding thiourea and acid metal salt to the diazo-fixed heat-sensitive recording material, it has high wrinkle sensitivity and excellent storage stability.
Furthermore, a diazo-fixed heat-sensitive recording material with improved background coloring could be obtained.

Claims (1)

[Scope of Claims] 1. Main ingredients are a diazonium salt, an acid as a pre-coupling inhibitor for a coupler compound, and a fine particle dispersion of a hydrophobic organic basic compound that is melted by heat and exhibits a basic atmosphere as a color developer. A diazo-fixed heat-sensitive recording material comprising a light-sensitive and heat-sensitive layer provided on a support, in which the light- and heat-sensitive layer contains thiourea and an inorganic acid having a dissociation constant equal to or larger than that of the acid; A diazo-fixed heat-sensitive recording material characterized by containing a metal salt of an organic acid in combination. 2. The diazo-fixed thermal recording material according to claim 1, wherein the hydrophobic organic basic compound is a hydrophobic guanidine derivative represented by the following general formula (I) or (II). General formula (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ General formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [In the formula, R_1, R_2, R_3, R_4, and R_5
represents hydrogen, alkyl, cyclic alkyl, aryl, aralkyl, amino, alkylamino, acylamino, carbamoylamino, heterocyclic residue having 18 or less carbon atoms, and R_
6 is lower alkylene, phenylene, naphthylene or ▲
There are mathematical formulas, chemical formulas, tables, etc. ▼ (in the formula, X represents lower alkylene, SO_2, S_2, S, O, -NH-, or a single bond), and the aryl group in the formula is lower alkyl, alkoxy, nitro, Also included are those having substituents selected from acylamino, alkylamino groups and halogens. ]