JPS60201986A - Thermal recording material - Google Patents

Abstract

PURPOSE:To enhance preservability in raw state and thermal color forming property, by a method wherein a diazo compound is microencapsulated, and a specified heat-fusible substance is incorporated, in a diazo thermal recording material. CONSTITUTION:A diazo compound serving as a core substance is dissolved in an organic solvent having a high boiling point such as a phosphoric acid ester and a phthalic acid ester, followed by emulsification, and microcapsule walls are formed around the core substance by polymerization. A coupling component and a basic substance are microencapsulated, dispersed as solids or dissolved in water to obtain an aqueous solution, and a material thus obtained is mixed with the microcapsule liquid. Further, at least one of a hydroxy compound having a melting point of 50-170 deg.C, a carbamic acid ester compound and an aromatic methoxy compound is added to the mixture obtained above, in an amount of 0.1-10.0pts.wt. per 1pt.wt. of the basic compound, to obtain a coating liquid, which is applied to a base, and is dried to obtain a thermal recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a heat-sensitive recording material, and particularly to a fixable diazo-based heat-sensitive recording material. More specifically, it has excellent storage stability before thermal recording.

Moreover, the present invention relates to a heat-sensitive recording material that has a high color density during thermal recording and can be optically fixed after thermal recording.

(Prior art) The method r, lz c) (1) does not require development; (2)
) When the support is paper, the paper quality is similar to ordinary paper, (3) it is easy to handle, (4) the color density is high, (5) the recording device is simple and inexpensive, and (6) recording. Due to its advantages such as no noise, it has become rapidly popular in the field of facsimiles and printers in recent years. 1it9 of this. As the recording material A, a leuco color-forming thermosensitive recording material is mainly used, which has a 1d difference in color density and color development speed.

However, with regard to leuco color-forming heat-sensitive recording materials, there are issues with handling, heating, and solvents after recording. It has the disadvantage that it develops color due to adhesion and stains the recorded image, and it also has the disadvantage that the color is erased by the precipitating agent in Matasero tape. In order to prevent color development due to careless handling, granular wax is added (% public 5o-ias
3i), and providing a covering layer to prevent the penetration of plasticizer (Utility Model Publication No. 4-/13Jμ) are known. However, this method is still not completely satisfactory and has not been used particularly for the purpose of preventing falsification after recording, and improvements have been strongly desired. rj~Recording As a method to stop the color development of unnecessary parts, 1'de 17-123
No. 016, JP-A No. 17-230-2, etc., a heat-sensitive recording material comprising a diazo compound, a coupling component, and an alkali generator or a coloring aid is used to produce light radiation after thermal recording. A known method is to decompose unreacted diazo compounds and stop color development. However, even with this record monthly rate, pre-coupling gradually progresses during storage, and undesirable coloring (fogging) may occur. For this purpose, contact between the components is prevented and pre-coupling is prevented by allowing one of the coloring components /r4 to exist in the form of discontinuous particles (solid content ¥i). However, the storage stability of the recording material (hereinafter referred to as raw storage stability) is still insufficient, and A': has the disadvantage that color development is reduced. Another known measure is to separate the 1-diazo compound and the coupler component in separate layers to minimize contact between the components. This method has good shelf life -iW
However, the thermochromic property is greatly reduced, and it cannot respond to short high-speed recording of pulse [1], making it impractical. Furthermore, as a method to satisfy both raw storage stability and thermal color development, either the coupling component or the basic substance (including substances that become basic when heated) are mixed with a non-polar wax-like substance (Japanese Patent Laid-Open No. 7
No. 7-aaia, JP-A-17-1442631. Vh I'i1t with other components by encapsulating it with a hydrophobic polymeric substance (Japanese Patent Application Publication No. 2003-2012/Tako2≠Hiroshi No.)
It is known to do. However, in these encapsulation methods, wax or polymeric substances are dissolved in their solvents, and coloring components are dissolved or dispersed in these solutions to form microcapsules. For this purpose, when the coloring component is dissolved and formed, the coloring component does not become the core material of the microcapsule, but rather mixes uniformly with the microencapsulated material, and precoupling gradually occurs at the wall interface of the microcapsule during storage. As the condition progresses, the shelf life is not fully satisfied. In addition, when a color-forming component is dispersed and formed, the color-forming reaction does not occur unless the walls of the microcapsules are thermally melted, resulting in a decrease in thermal color-forming properties. Furthermore, there is a manufacturing problem in that the solvent used to dissolve the wax or polymer substance must be removed after forming the microcapsules, which is not completely satisfactory.

(Purpose of description) Therefore, the purpose of the tF7 of the present invention is to have excellent shelf life and
The object of the present invention is to provide a heat-sensitive recording material with high color development.

The second purpose of the present invention is to photodecompose the unreacted diazo compound after thermal recording to stop color development in unnecessary areas (hereinafter referred to as
4"ζ4A1'; all 4 are provided.

A third object of the present invention is to provide a thermal recorder with excellent manufacturability.

((1°1 formation of the invention) As a result of intensive research, the present inventors have found that on the support + 1 body, a diazo compound, a coupling component and
? In a heat-sensitive recording material provided with a writing layer containing a λ-occlusive physical substance, the diazo compound is contained in microcapsules,
Furthermore, the ratio is achieved by a heat-sensitive recording material comprising at least one of a hydroxy compound, a carbamate ester compound, and an aromatic methoxy compound with a 1U point jO°C-/7θ0C.

The microcapsules of the present invention can be ruptured by heat or pressure, as used in conventional recording methods, to bring all of the reactive substances contained in the core of the microcapsules into contact with the reactive substances outside the microcapsules. This method does not cause a coloring reaction, but instead generates a reaction by heating the core of the microcapsule and the reactive substance present on the outside, causing the microcapsule wall to react. It is known that when formed by a polymerization method, it is not completely impermeable but has permeability.This permeation PL of the microcapsule wall is a phenomenon in which low-molecular substances gradually permeate over a long period of time. However, the phenomenon of instantaneous transmission due to heating as in the present invention was not known.

Therefore, the microcapsule walls of the present invention do not need to be melted by heat; rather, it has been found that the higher the melting point of the walls, the better the shelf life.

Even when the core substance of the microcapsule liquid produced by the method of the present invention is removed and heated, the walls are almost 15 T.
Don't do it.

By selecting the material and film thickness of the microcapsule wall, the core material of the microcapsule can be
Even if the chair is in good condition, semi-solid state or solid state, +1 is "old 11;".
It is preferable because it causes transmission or color reaction for about 1 c.

Therefore, as the core substance component of the present invention, it is preferable to use a solvent having a high boiling point of '81 at room temperature.

The hydroxy compound, carbamate ester compound, and aromatic methoxy compound of the present invention have a higher temperature than commonly used thermofusible substances. Thermochromic tL gold can be significantly improved. It is believed that these compounds lower the melting point of the coupling component and the basic substance, and further improve the thermal permeability of the microcapsule wall, resulting in a higher practical concentration.

Specific examples of hydroxy compounds include p + -butylphenol, p-1-octylphenol, p-α-cumylphenol, p-1-pentylphenol, m-xylenol, λ, j-dimethylphenol, co, ≠ I! −
Trimethylphenol, 3-methyl-Hiro-isopropylphenol, p-benzylphenol, 0-cyclo-hexylphenol, p (diphenylmethyl)phenol, p-(α,α-diphenylethyl)phenol, 0
- phenylphenol, ethyl p-hydroxybenzoate, chloropyr p-hydroxybenzoate, butyl p-hydroxybenzoate, benzyl p-hydroxybenzoate,
p-methoxyphenol, p-butoxyphenol, p
-hebutyloxyphenol, p-benzyloxyphenol, dimethylvanillin 3-hydroxyphthalate, 1
．． /-bis(4=-hydroxyphenyl)dodecane, /
, /-his(≠-hydroxyphenyl)-λ-ethylhexane, 1. /-bis(<2-hydroxyphenyl)
-Comethyl-bentane, 1,2-bis(≠-hydroxyphenyl)-hebutane vanillin, J-t-butyl-l-methoxyphenol, λ.

t-Dimethoxyphenol 1. Z, phenolic compounds such as 2'-dihydroxy-methoxybenzophenone, co,j-dimethyl-λ,j-hexanediol, resorcinol di(λ-hydroxyethyl) ether, resorcinol mono(2-hydroxyethyl) ether, salicyl Alcohol, 1, ≠-di(hydroxyethyl)
Benzene, p-gycylylene diol, l-phenyl-/
, 2-ethanediol, diphenylmethanol, 1.
l-cyphenylethanol, λ-methyl-cophenylated i, 3-propanediol, 2,4-dihydroxymethyl-p-cresol benzyl ether, λ, t-dihydroxymethyl-p-cresol benzyl ether, 3
Examples include alcohol compounds such as -(o-methoxyphenoxy)-/, 2-propanediol, and the like. Specific examples of carbamate ester compounds include N-phenylcarbamate ethyl ester, N-phenylcarbamate benzyl ester, N-phenylcarbamate phenethyl ester, carbamate benzyl ester, carbamate butyl ester, carbamate isopropyl ester, etc. can be mentioned. Specific examples of aromatic methoxy compounds include λ-methoxybenzoic acid, 3. j-dimethoxyphenylacetic acid, comethoxynaphthalene, l, 3. j-)
One amount of rimethoxyminzene, p-dimethoxybenzene, p-benzyloxymethoxybenzene, etc. can be made.

The amount of these compounds to be used is 0.0 to 0.0, preferably 0.0 to 0.0, based on 1 weight part of the basic substance qt (1 weight part).
1- parts by weight are preferred.

The diazo compound used in the present invention has the -strike formula A r N
It is a diazonium salt represented by 2 +X-, and is a compound that can develop a color by causing a coupling reaction with a coupling component, and can be decomposed by light. (In the formula, Ar represents a substituted or unsubstituted aromatic moiety, N2+ represents a diazonium group, and X- represents an acid anion ki%.) Specific examples of diazonium compounds that form salts include Gudiazo-/ -dimethylaminobenzene, 〃-thiazo/-diethylaminebenzene, l-diazo-l-dipropylaminobenzene, j-thiazo/-methylbenzylaminobenzene, μ-diazo/-dibenzylaminobenzene, μm-thiazo/-ethylhydroxy Ethylaminobenzene g-diazo-7-ethylamine-3-methoxybenzene, t-diazo-1-dimethylamino-λ
-Methylbenzene, μm shea 7”-/-benzoylamino-λ, j-jethoxybenzene, ≠-diazo/-morpholinobenzene, t-diazo-1-morpholino, 2
．． 5-Jethoxybenzene, gudiazo-/-morpholino-2,! -Dyptoquinbenzene, lt-Thiaso 7-
Anilitubenzene, t-diazo-7-tolylmercapto-2,! -diethoxybenzene, t-diazo-/, 1
7-methoxybenzoylamino-2,j-jethoxybenzene''.j: is mentioned.

1] Specific examples of quanions include CnF2n-t-I
C00- (11 is truncated from 3 to y), CmF2m-1-t
sOa (m is an integer from 2 to g), (C/F211+l5
O2)2CH- (l is an integer of / , /♂), 03- / (,'ll 3 (n is an integer of 3 to 3) Perfluoroalkyl as a special dioxide anion]'3F
4-1PFa- and the like.

or perfluoroalkenyl group, or PF6- is preferable because it causes less fog during raw storage.

(Specific examples of the diazo compound (diazonium salt) include the following examples.

0C4H.

0C:4119 OU41 (9 wood'; J as a coupling component used for Li light
・S＋'g t'J', ;";-It is a substance that forms a total pigment by coupling with a diazo compound (diazonium salt) in an ambient atmosphere, and ↓L'(l) Examples include resorcinol, phloroglucin, 2゜3-Dihydrogycinafta V-t-
Lithium sulfonate, l-hydroxy-2-naphthoic acid morpholinopropylamide, /, j-dihydroxynaphthalene, λ, 3-dihydroxynaphthalene, co.

3-dihydroquino t-sulfanylnaphthalene 1.2
-Hydroxy-3-naphthoic acid morpholinopropylamide, 2-hydroxy-3-naphthoic acid anilide, λ-hydroxy-3-naphthoic acid-2'-methylanilide, euhydroxy-3-naphthoic acid 11'2 ethanolamide, no-hydroxy- 3-nanthoic acid octylamide, euhydroxy-3-naphthoic acid-N-dodecyl-oxy-propylamide, no-hydroxy-3-naphthoic acid ν
Tetradecylamide, acetanilide, acetoacetanilide, benzoylacetanilide, l-phenyl-3
-Methyl-y-pyrazolone, /-(2', It', 4'
-)lichlorophenyl) -3-benzamide-! -pyrazolone, /-(,2',U,',/,'-)lichlorophenyl)-3-anilino-j-pyrazolone, l
Examples include -phenyl-3-phenylacetamide and pyrazolone. Furthermore, these coupling components are 2
i11]i of any color tone by using more than one species in combination
@k can be obtained.

As the basic substance of the present invention, a water 6j'j: Fak or water-insoluble basic substance or a substance that generates an alkali upon heating is used.

Basic substances include inorganic and organic ammonium salts, organic amines, amides, urea and thiourea and their derivatives, thiazoles, pyrroles, pyrimidines, radines, guanidines, indoles, and imidazoles. ,
imidacillin;l:lj,)lyazole,':,'t'
i, morpholines, piperidines, amidine]; η,
Examples include nitrogen-containing compounds such as formazines and pyridines. Specific examples of these include ammonium acid, tricyclohexylamine, tribenzylamine, octadecylbenzylamine, stearylamine, allyl urea, thiourea, methylthiourea, allylthiourea, ethylenethiourea, cobenzylimidazole,
gouphenylimitasol, λ-phenyl-$-methyl-imidazole, coundecyl-imidazoline, λ
, &, 1-) rifudyl-2-imidacilline, ' 1-diphenyl-ψ, 4A-dimethyl-coimidazoline,
Cophenylu-λ-imidacillin, l.

2,3-) Riphenylguanidine, /, cordytolylguanidine, 7,2-dicyclohexylguanidine,
/, 2. ! -) dicyclohexylguanidine, guanidine trichloroHCrZjL N, N'-dibenzolby includes radine, p,<z'-dithiomorpholine, morpolinium trichloroacetate, co-aminobenzothiazole, λ-benzoylhydrazinobenzothiazole. Two or more of these basic substances can also be used in combination.

In the present invention, the reactive substance contained in the core substance of the microcapsule is treated with a water-insoluble solvent (6kr), emulsified, and then a microcapsule wall is formed around it by polymerization, which completely improves the shelf life. It is effective in loading to increase color development speed and color density.70% as a specific solvent
Those with a boiling point of 0C or more are preferably used, such as phosphoric acid esters, phthalic acid esters, other carboxylic acid esters, fatty acid amides, alkylated biphenyls, alkylated terphenyls, chlorinated) ξ rough ins, alkylated naphthalenes, diarylethanes, etc. It will be done. Specific examples include tricresyl phosphate, trioctyl phosphate, octyldiphenyl phosphate, tricyclohexyl phosphate, dibutyl phthalate,
Dioctyl phthalate, dilauryl phthalate, dicyclohexyl phthalate, butyl oleate, diethylene glycol dibenzoate, dioctyl sepacate, dibutyl sepacin, dioctyl adipate, trimellit rI
1-ctyl, acetyl triethyl citrate, maleiso r+2 octyl, dibutyl maleate, isopropylbiphenyl, isoamyl biphenyl, chlorinated breadfin, diisopropylnaphthalene, 1. l'-ditolylethane 1.2.4A-ditertiaryaminophenol,
Examples include N,N-ditutyl-λ-butoxy- and tertiaryoctylaniline.

Among these, dibutyl phthalate, tricresyl phosphate,
Diethyl phthalate, dibutyl maleate, “′:Q)
Ester solvents are preferred.

Mikjowo Ming's microcapsules contain and cure reactive substances.
It is made by emulsifying a core material and then forming a wall of polymeric material around the oil droplets. The actant forming the polymeric material is added to the interior of the oil droplet and/or to the exterior of the oil droplet.

Specific examples of polymeric substances include 11? Examples include urethane, polyurea, polyamide, solidester, polycarbonate, urea-formalghyde resin, melamine resin, polystyrene, styrene methacrylate copolymer, styrene-acrylate copolymer, gelatin, polyvinyl bitetraridone, polyvinyl alcohol, and the like.

Two or more types of polymeric substances can be used in combination.

Preferred polymeric materials are polyurethane, polyurea, polyamide, polyester, polycarbonate, more preferably polyurethane and polyurea.

Among the diazo compounds, coupling components, and basic substances that are the main components used in the present invention, the core materials of microcapsules include diazo compounds, coupling components, basic substances, diazo compounds and coupling components, and diazotized adducts. and a basic substance, or a coupling component and a basic substance can be used. Lifts using two types of core materials can be contained in the same microcapsule or in separate microcapsules. Other ingredients not used as the core material of the microcapsules are used in the heat-sensitive layer outside the microcapsules.

In order to prepare the microcapsule walls of the present invention, a microencapsulation method in which a glue actant is polymerized from inside an oil droplet is particularly used.''150 This method is highly effective. That is,
Which Kabul is preferable as a recording material that has uniform particle size within a short period of time and has excellent shelf life? l, l can do it.

This method and specific examples of compounds are described in Kiguchi 7i'10' ``No. 3,726.10ψ, 3,7Yt, t6 t.

t' Polyurethane is used as the capsule wall material.

In 1'1, a polyvalent inocyanate and a second substance (e.g., a polymer) that reacts with it to form capsules are mixed into the oily liquid to be encapsulated, emulsified and dispersed in water, and then By increasing the temperature to A single molecule formation reaction occurs to form a microcapsule wall. At this time, a low boiling point solution 1'T in the oily liquid
Strong cosolvents can be used.

this"! In this case, regarding the polyinocyanate to be used and the polyol and polyamine to be reacted with it, US Pat. -' for Haro 371ri 321.lr, special public 44J'-110
3≠7, same 4'? -21/-/j; No. JP-A Showμm
They can also be used.

Furthermore, tin JR:X or the like can also be used in combination to promote the urethanization reaction.

In addition, by combining polyvalent isocyanate, which is the first wall-forming substance, and polyol, which is the second wall-forming substance (q) I, it is possible to change the permeability of the metal to any reactive substance. .

Examples of the polyvalent isocyanate that is the first wall-forming substance in the present invention include m-phenylene diisocyanate and p-phenylene diisocyanate (1.2.4-).
Relene diisocyanate, 2° heat relene diisocyanate, naphtha L/N-L.

≠-diisocyanate, diphenylmethane-≠.

q'-diisocyanate, 3.3'-dimethoxy-≠,
4A'-biphenyl diisocyanate, 3゜31-dimethyldiphenylmethane-≠, 4A'-diisocyanate, xylylene-1,φ-diisocyanate, φ, Hiro'
-Diphenylpropane diisocyanate, trimethylene diisocyanate, hexagonal diisocyanate, propylene -7゜λ-diisocyanate, butylene-
1,λ-diisocyanate, cyclohexylene-7,λ
-diisocyanate, cyclohexylene-/, diisocyanate such as Hiro-cyisozoanate, ≠I.

triisocyanates such as 4t, //-triphenylmethane triisocyanate, toluene-λ, 41.4-) diisocyanate, tetras such as μ,II-'-dimethyldiphenylmethane-λ,2',j,j'-tetraisocyanate Incyanate, adduct of hexamethylene diisocyanate and trimethylolpropane, adduct of ≠-tolylene diisocyanate and trimethylolpropane, adduct of xylylene diisocyanate and trimethylolpropane, addition of tolylene diisocyanate and hexanetriol There are incyanate prepolymers such as

In the present invention, the second wall-forming substance polyol (7) includes polyols such as aliphatic and aromatic polyalconopehydroxy polyesters and hydroxypolyalkylene ethers. Examples include polyhydroxy compounds having the following (I), (n), (III) or (iV) (7') M t in the molecular structure between the hydroxyl groups and having a molecular weight of zooo or less.

■ Here, A r i of (II), (III), and (IV)
i: (i' represents a substituted or unsubstituted aromatic moiety, and the aliphatic hydrocarbon group (■) is -Cnl-J2n
'l: A basic skeleton, and the hydrogen group may be substituted with another element.

To give a specific example, examples of (I) include ethylene glycol, /6. ? -iropanediol, l, ≠-butanediol, i, z-: tantanediol, 1. -hexanediol, no,7-hebutansinol, i,r-
Octanediol, propylene glycol, 2,3-dihydroxybutane, 1,2-dihydroxybutane, 1.
3-dihydroxybutane, 2-dimethyl-/, 3-
To propane 2. l-bentanediol, λ,!
-hexanediol, 3-methyl-7,j-pentanedionope l,l/--cyclohexane dimetatool,
dihydroxycyclohexane, diethylene glycol,
/, 2.7-) lyhydroxyhexane, phenylethylene glycol, i,i,i-trimethylolpropane, hexanetriol, penquerythritol, glycerin, and the like.

As an example of (11), 1. Examples include condensation products of aromatic polyhydric alcohols and alkylene oxides such as ≠-di(-2-hydroxyethoxy)benzene and resorcinol dihydroxyethyl ether.

Examples of (m) include p-xylylene glycol, m
-xylylene glycol, α, α′-dihydroxy-p
-diisopropylbenzene, etc.

Examples of (IV) include Hiroshi, μ'-dihydroxydiphenylmethane, λ-(p,p'-dihydroxydiphenylmethyl)benzyl alcohol, adducts of ethylene oxide to bisphenol A, and additions of propylene oxide to bisphenol A. Things can be given. It is preferable to use the polyol in such a manner that the hydroxyl group allocation is θ, O-2 to comole per mole of isocyanate group.

When making microcapsules, water-soluble polymers can be used.Water-soluble polymers include water-soluble anionic polymers, nonionic polymers, and amphoteric polymers. Both natural ones and synthetic ones can be used, and examples include those having a -C00-1-so3 group. Specific anionic natural polymers include gum arabic and alginic acid, while semi-synthetic products include carboxymethyl cellulose, phthalated gelatin, sulfated starch, sulfated cellulose, and lignin sulfonic acid.

Synthetic products include maleic anhydride-based (including hydrolyzed) copolymers, acrylic acid-based (including methacrylic acid) polymers and copolymers, and vinylbenzenesulfonic acid-based polymers and copolymers. , carboxy modified V1 Nipoliviny/I
/'Alcohol etc.

Examples of nonionic polymers include polyvinyl alcohol, hydroxyconitylcellulose, and methylcellulose.

Examples of amphoteric compounds include gelatin.

These water-soluble polymers are used as water-soluble polymers for θ, O7-7OWt'I). Microcapsule ;:i diameter p, l,! Adjusted to below OB. Generally, the particle size is -
If 0n 'x '1.1' = higher, the print image quality tends to deteriorate.

In particular, when applying heat from the coating layer side using a thermal head, "2.
The following is feminine.

When making microcapsules, they can be made from an emulsion containing 0.2 wt% or more of the component to be microencapsulated.

Diazo compound used in the present invention, coupling component,
Whether the basic substance is contained inside the microcapsule or in the photosensitive layer outside the microcapsule, the amount of the coupling component is 0.7 parts by weight per 7 parts by weight of the diazo compound. /~/ Oii7 ;Meter part, color development aid is O:/~
20'ij; It is preferable to use it with all at the end. Also, the diazo compound is 0゜Oj-j, Og/11
It is preferable to apply 12 coats.

When the diazo compound, coupling component, and basic substance used in the present invention are not microencapsulated, it is preferable to use a solid fraction using a sand mill or the like. Preferred water-soluble polymers include water-soluble sieve molecules used when making microcapsules. At this time, the concentration of the water-soluble polymer is 2 to 30w1%, and the diazo compound, coupling component, and basic substance are each added to this water-soluble polymer bath solution! - HiroshiOwt% is added.

The dispersed particle size is preferably less than IOμ.

For the purpose of preventing sticking to the thermal head and improving writing properties, the thermal recording monthly fee contains silica, barium sulfate, titanium oxide, aluminum hydroxide,
It can be used for pigments such as zinc oxide and calcium carbonate, and fine powder hair such as styrene beads, urea-melamine 4G, and f fat.

Similarly, metal soaps can also be used to prevent sticking. The ratio of these used is 0.2 to 79/m2.

Furthermore, a heat-melting substance can be used in the heat-sensitive recording material of the present invention in order to increase the heat recording density.

, F3 as 歭t g'g + As a biological substance, it is solid at room temperature and melts by heating with a thermal head, with a melting point jO~
/ j It is an O'C substance, and it is a substance that dissolves a diazo compound, a coupling component, or a basic substance. The heat-fusible substance is dispersed in the form of particles of 0,i~10μ and used at a solid content of 012~'#/m2. Specific examples of the thermofusible substance include fatty acid amide, N-1 acute fatty acid amide, ketone compound, urea compound, ester j, and tl.

The heat-sensitive recording material of the present invention can be used with a suitable /ζ inder.

Binders include polyvinyl alcohol, methylcellulose, carboxymethylcellulose, hydroxypropylcellulose, gum arabic, gelatin, polyvinylpyrrolidone, casein, styrene-butadiene latex, acrylonitrile-butadiene latex, polyvinyl acetate, polyacrylic ester, ethylene-vinyl acetate. Various emulsions of copolymers can be used. The amount used is 3-j El/m 2 with a solid content of 0.

In the present invention, in addition to the above materials, citric acid is used as an acid stabilizer.
Tartaric acid, oxalic acid, boric acid, and pyrophosphoric acid can be added.

The heat-sensitive recording material of the present invention is produced by adding a diazo compound, a coupling component, a main component of a basic substance, and other additives as a core material of microcapsules, or dispersing them as a solid, or dissolving them as a limestone solution. Mix to make a coating solution, and apply I and Y commercial methods such as bar coating, plaid 1-police cloth, air knife coating, gravure coating, roll coating, spray coating, dip coating, etc. onto a support such as paper or synthetic resin film. After coating and drying, solid content λ,!
A heat sensitive layer of ~219/1rL2 is provided. Another method is to add the coupling component, the main component of the basic substance, and its additives as the core material of the microcapsule, or to disperse them as a solid, or to dissolve them as an aqueous solution and mix them to form a coating solution. After production, a precoat layer with a solid content of 2~/Og/TrL2 is provided on the support by drying f' fabric, and then the main component diazo compound and other additives are added to the core material of the microcapsule. Alternatively, a coating solution made by adding it as a solid content of 1 ik or dissolving it as an aqueous solution and mixing it is applied and dried to form a laminated type with a coating layer of solid content /~/jj)/m2. It's also possible. Among the diazo compounds, coupling components, and basic substances that are the main components of these heat-sensitive recording materials,
At least one species is contained in microcapsules.

The microcapsules may contain two types at the same time.

Alternatively, the three types may be contained in separate microcapsules, or two types may be contained in the same microcapsule and the remainder contained in another microcapsule.

In the laminated type heat-sensitive recording material, the order of the layers is '4';
The layers can be reversed, and the coating method can be lamination and sequential purification or simultaneous coating. This laminated heat-sensitive recording material exhibits particularly excellent performance in long-term storage.

The paper used for the support is heat extracted pH 6 sized with a neutral sizing agent such as an alkyl ketene dimer.
- Neutral paper (described in Japanese Patent Application Publication No. 2003-11-11) 1
It is advantageous in terms of preservation over time.

In addition, in order to prevent the coating liquid from penetrating into the paper and to improve the contact between the recording heat head and the heat-sensitive recording layer, there is
The paper described in No. 617 and having a Bekk smoothness of 20 seconds or more is advantageous.

Also, the optical surface i71 described in Japanese Patent Application No. 57-200≠7
Paper with a diameter of I /A or less and a thickness of po ~ 7 j it, 'l'lN l;:, i Showa 5r-x θri / written density of 0129 /cm3 or less and an optical contact ratio of IJ ′
% or more, Canadian Standard Water Intensity (JIS PI/2/) T4/ as described in JP-A-1-4-7
- 00 copies or more double-beat 8"fi treatment ij! Paper made from Lada pulp to prevent coating liquid from seeping in, JP-A-6L-4
3-A, which improves the color density and resolution by applying the coating to the glossy surface of base paper made by a Yankee machine, especially 1゛Old! ('3 j 7- / Hirojt 7.
The base paper was subjected to corona radiation 1;L4'' treatment as described in 2, and φ
Papers with completely improved fabric suitability, etc., can also be used in the present invention with good results. In addition to these) IT, i'i:s feeling O,
Any support used in recording paper can be used as the support in the present invention.

The i: & It is possible to make a red store. In addition, it can also be used as a heat-developable paper.

Examples are shown below, but the present invention is not limited thereto. In addition, "1 part" indicating the addition amount represents "part by weight".

Example 1 Part λ of the following diazo compound and 1r part of the (J:/) addition of xylylene diisocyanate and trimethylolpropane were added to a mixed solvent of 5 parts of dibutyl 7-talate and 5 parts of vinegar and ethyl, and dissolved. did. A solution of this diazo compound was mixed with 3.5 parts of polyvinyl alcohol, 7.7 parts of gelatin,
A-di(2-hydroxyethoxy)benzene, 2. The mixture was mixed with an aqueous solution in which μ part was dissolved in j 1 part 1 c of water, and emulsified and dispersed with COOC to obtain an emulsion having an average particle size of 3 μm. Add 100 parts of water to the obtained emulsion, and add 60 parts of water while stirring.
After heating to 0C and after 4 hours, capsule liquid containing a diazo compound in the core substance kmft.

Next, λ-hydroxy-3-naphthoic anili”, 2
The mixture was added to 100 parts of an aqueous solution of j% polyvinyl alcohol and dispersed in a sand mill for about 2≠ hours to obtain a dispersion of a coupling component having an average t-nia diameter of 3/f.

Next, 20 parts of triphenylguanidine was added to 100 parts of a tl polyvinyl alcohol aqueous solution and dispersed in a sand mill for about λ hours to obtain a dispersion of triphenylguanidine with an average particle size of 3 μm.

Further, 20 parts of p-1crt-octylphenol + 20 parts of Tano polyvinyl alcohol aqueous solution Fc were added and dispersed in a sand mill for about 4 hours to obtain p-Le with an average particle size of 311.
A dispersion of rt-octylphenol was obtained.

Capsules of the diazo compound obtained as above!
'ijO part, 75 parts of coupling component dispersion and 75 parts of triphenylguanidine dispersion, 1)-1crt
- 3 parts of an octylphenol dispersion was added to prepare a coating solution. Apply this coating solution to smooth high-quality paper (CjOg/m2) using a coating rod and dry it in a dry P'JfL amount of 209/m2.
It was coated with a powder to give a coating thickness of m2VC and dried for 30 minutes to obtain a heat-sensitive recording material.

Examples 2 to 3 In place of p-tcrt-octylphenol in Example 1, co-, t-dihydroxymethyl-p-cresol benzyl ether and N-phenylcarbamic acid phenethyl ester were used, and 1:1 was used. A thermosensitive recording material was obtained in the same manner as in Example 1.

Example 4 The following diazo compound λ part and the (J:/) adduct of xylylene diisocyanate and trimethylolpropane/3.1
Part, tolylene diisocyanate and trimethylol pro-
(J:/) adduct of ξ≠.

5 parts were added to a mixed solvent of 1 part dibutyl phthalate and 5 parts ethyl acetate and dissolved. This solution of diazo compound is
Polyvinyl alcohol was mixed into an aqueous solution in which 2 parts were dissolved in 1 part water, and emulsified and dispersed in -〇〇〇 to obtain an emulsion with an average particle diameter of 77. Add water “ioo” to the resulting emulsion.
After 4 hours, a capsule liquid containing a diazo compound in the core substance was obtained.

Diazo Compound Next, 2θ parts of λ-hydroxy-3-naphthoic acid anilide was added to 700 parts of J-4 polyvinyl alcohol aqueous solution and dispersed in a sand mill for about 2 hours to obtain a dispersion of coupling components with an average off-diameter of 3μ. Obtained.

Next, part of triphenylguanidine λO was added to 100 parts of a j% polyvinyl alcohol water bath solution and dispersed in a sand mill for about 2 hours to obtain a dispersion of triphenylguanidine with an average particle size of 3 μm.

Further, 20 parts of I)-xylylene diol and 700 parts of an aqueous f7% polyvinyl alcohol solution were added and dispersed in a sand mill for about λμ hours to obtain a dispersion of p-xylylene diol having an average particle size of 3μ.

To 0 parts of the capsule liquid of the diazo compound obtained as above, 75 parts of a coupling component dispersion, lj parts of a triphenylguanidine dispersion, and 30 parts of a p-xylylene diol dispersion were added and applied. It was made into a liquid. This coating solution was bar coated onto smooth high-quality paper (jO,!i'/m2) using a coach-in-blonde so that the dry weight was 209/m'', and dried for μj0CJO minutes to obtain a heat-sensitive recording material. .

Example 5 3.44 parts of the following diazo compound and 1r part of a (3:l) adduct of xylylene diisocyanate and trimethylolpropane were added to a mixed solvent of 2 parts of tricresyl phosphate and 5 parts of ethyl acetate and dissolved. .

This diazo compound solution was mixed with polyvinyl alcohol 3.
2 parts are dissolved in water St part and mixed into water stone solution 1.2
Emulsification and dispersion was carried out at 00C to obtain an emulsion with an average particle size of jμ. IOO parts of water was added to the obtained emulsion and heated to 0.0C while stirring, and after 2 hours, a capsule liquid containing a diazo compound in the core substance was obtained.

Diazo compound Next, in addition to 70 parts of 2-hydroxy-3-naphthoic acid anilide and 10 parts of triphenylguanidine = 100 parts of a 2 tl polyvinyl alcohol aqueous solution, approximately 2 q.
A time-dispersed dispersion of coupling components and triphenylguanidine with an average particle size of 3μ 'fc? ! )Ta.

Further, the mixture was added to 20 parts of p-benzyloxyphenol and 700 parts of a 3% polyvinyl alcohol aqueous solution and dispersed in a sand mill for about 21 hours to obtain a dispersion of p-benzyloxyphenol having an average particle size of 3 .mu.m.

Capsule liquid of diazo compound obtained as above 5
To 0 parts, λμ parts of a dispersion of the coupling component and triphenylguanidine, and 2 parts of a dispersion of p-benzyloxyphenol were added to prepare a coating liquid. This coating solution was bar coated onto a smooth high-quality paper (to, !il/m2) using coach-in-blonde so that the dry weight was 1OI/TrL2, and dried for 30 minutes at μ00C to obtain a heat-sensitive recording material.

Example 6 In place of p-benzyloxyphenol in Example 5/
3. j-) Example 5 except that rimethoxybenzene was used.
Similarly, heat-sensitive recording material 'N! )Ta.

Comparative Example 1 A heat-sensitive recording material was obtained in the same manner as in Example 1, except that p-1ert-octylphenol in Example 1 was omitted.

Comparative Example 2 A heat-sensitive recording material was obtained in the same manner as in Example 5, except that p-benzyloxyphenol in Example 5 was omitted.

Comparative Example 3 A heat-sensitive recording material was obtained in the same manner as in Example 1 except that stearic acid amide was used instead of p-tert-octylphenol in Example 1.

(Trial 1 method) Heat recording was performed on the prepared heat-sensitive recording material using GIII mode (Hifax 7oo) (manufactured by Hitachi, Ltd.).
Next, Ricopy Sue/ξ-Dry 100 (Ricoh <+:+
The entire surface was exposed to light using a commercially available commercially available product (manufactured by )) and fixed. The obtained recording surface @ is measured with a Macbeth reflectance meter.
! 'L 'c 6i! I decided. The results are shown in Table ■. On the other hand, when thermal recording was performed on the constant z+Ef portion, it was found that no image was recorded and the image was fixed.

Next, in order to check the shelf life of the heat-sensitive recording material,
fog) and them ≠00C, relative humidity y o % 1
1. It was stored in a dark place for 2≠ hours under the conditions of 1-I, and after performing a forced deterioration test, the fog was measured using a Macbeth reflex 0 deer meter to observe changes in fog. The results are shown in Table I.

From Table I, Example 152.4.5 in which a diazo compound was encapsulated and further added a hydroxy compound, Example 3 in which a carbamate ester compound was added, and Example 3 in which an aromatic methoxy compound was further added. 6 shows the image e! The density is uniformly high, the increase in fog after the forced deterioration test is small, and it is an excellent thermal recording 44-1.

Furthermore, it can be seen that the thermal coloring property is much better than that of Example 3, which has a ratio of I:A, which is a mixture of the generally used thermoplastic t and X' and a chemical substance added thereto.

In addition, Examples 1 to 6 all improved the whiteness of the heat-sensitive recording materials, and the sticking properties were good and durable.

Claims (1)

[Claims] A heat-sensitive recording material in which a recording layer containing a diazo compound, a coupling component, and a basic substance or a substance that becomes basic by heat is provided on a support, the diazo compound being contained in microcapsules, and further comprising: , melting point 20~
A heat-sensitive recording material containing at least one kind of a hydroxy compound, a carbamate ester compound, and an aromatic methoxy compound at Hp:r C1 of /70°C.