JPS602396A - Fixable-type thermal recording material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fixable heat-sensitive recording material that develops color with high density during heat-sensitive recording and has good storage stability.

In recent years, high-speed printers, facsimile machines, etc. have made remarkable progress in response to society's demand for outputting large amounts of information as quickly as possible.

Electrophotography, electrostatic recording, discharge recording, inkjet recording, thermosensitive recording, and the like are known as methods for forming image ridges on recording media according to electrical information, such as in high-speed printers and facsimiles. Among these methods, the thermal recording method has been rapidly becoming popular in recent years because the apparatus is relatively simple and the recording paper is also relatively inexpensive.

As one method of the heat-sensitive recording method, a heat-sensitive recording sheet made of a combination of a color-forming substance such as crystal violet lactone and a phenolic compound such as bisphenol A is described in, for example, Japanese Patent Publication No. 14039/1983. It is already known. These thermosensitive recording sheets are currently widely used as office copy paper, recording paper for various recorders, electrocardiographs, calculators, computer terminals, facsimiles, and the like.

However, in the above-mentioned conventional method, if the printing is mistakenly heated after printing, the background becomes colored and the printing becomes unreadable, and there is a possibility that the printing may be tampered with.Therefore, improvements are strongly desired.

The present inventors have solved this problem by developing a fixable 6f'.1.
Research was conducted with the intention of providing a heat-sensitive recording material, and by first promoting the reaction of a diazonium salt and a coupler compound, and using a guanidine rust conductor having a specific general formula as a '1'-jK radical substance, He discovered that it would be possible to provide a fixable heat-sensitive recording medium with high sensitivity and excellent storage stability, and he had already proposed it (Japanese Unexamined Patent Publications No. 57-45094, No. 57-12).
509] Publication).

An object of the present invention is to provide a fixable heat-sensitive recording material that develops color with high density during heat-sensitive recording and has excellent storage stability.

Namely, the fixable heat-sensitive recording material of the present invention includes a support, a diazonium salt, a coupler compound, a color development aid, and fine particles of an organic basic compound as a color developer that exhibits a basic atmosphere when dissolved by heat. In a fixing type thermosensitive recording material in which a dispersion is provided in the same layer or as a photothermosensitive layer consisting of two or more separate layers, the following general formula (1) or (I) is used as a coloring auxiliary agent.
It is characterized by using a fatty acid amide derivative represented by:

General formula (1) %formula% General formula (1) R3CONH(CH2)nNHCOR.

In the formula, R,, R, is a saturated or unsaturated alkyl group having 4 to 26 carbon atoms, R8 is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a phenyl group, a cycloalkyl group, and n is 1.2 or 3. indicates an integer.

Note that R1s'4 and R3 may be substituted with a substituent.

The fatty acid amide derivative used in the present invention has a melting point of 40 to 160.
It is a solid substance at room temperature, preferably 70 to 145°C, is poorly soluble or insoluble in water, and easily dissolves diazonium salts, coupler compounds, and organic basic compounds used as color developers when hot melted. It is preferable to use one that does.

Specific examples of fatty acid amides of general formula (1) used as coloring aids are shown in Table 1 along with their melting points.

Table-1 Melting point Caproic acid amide 101°C Caprylic acid amide 105°C Capsonic acid amide 99°C Lauric acid amide 1.00°C Myristic acid amide 103°C Palmitic acid amide 106°C Stearic acid amide 109°C Behenic acid amide 112°C Oleic acid amide 7G'C Eicosene 1 Shunamide 79'C Stearic acid methylolamide 105℃ Also, the general formula (
Table 2 shows specific examples of fatty acid amide derivatives of the Japanese iris, together with their melting points.

Table-2 Melting point Methylene biscapric acid amide 160°C Methylene bislauric acid amide 155°C Methylene bismyristic acid amide 151°C Methylene bispalmitic acid amide 1
48°C Methylenebisstearamide 145°C Methylenebisbehenic acid amide 142°C Methylenebisoleic acid amide 118°C Methylenebis-eicosenoic acid amide 122°C Methylenebisstearic acid amide 140°C
All of the above compounds used as coloring aids in the present invention are heat-fusible, poorly soluble or insoluble in water, and have a particle size of 0.
It is used in the form of fine particles of 1 to 10 microns.

The ratio of diazonium salt, coupler compound, and coloring aid of the present invention is 1:(0,1-10):(0,1-20)
(weight) range is preferable.

Further, the coloring aids can be used alone or in combination of two or more types if necessary.

The object of the present invention is to use a fine particle dispersion of an organic basic compound which melts under heat and exhibits a basic atmosphere as a color developer and the general formula (1) of the present invention for diazonium salts and coupler compounds.
Or (the phantom fatty acid amide derivative is used in combination as a coloring aid. In other words, sufficient color density cannot be obtained by simply using an aliphatic amide derivative as a coloring aid for a diazonium salt and a coupler compound. Furthermore, if a basic compound soluble in the solvent used for coating the light and heat sensitive layer is used as a color developer, storage stability will be deteriorated.

By using the color development aid of the present invention in combination with a color developer dispersed in fine particles, it is possible to obtain a fixing type heat-sensitive recording material that has improved staining resistance, develops color at high density, and has excellent storage stability. I can do it.

The effect of improving the color development sensitivity of a fixable heat-sensitive recording material by the color development aid of the present invention is observed not only when a hydrophobic guanidine derivative is used but also when a widely known organic basic compound is used as a color developer, but it is particularly preferable. Examples of organic basic compounds include the following guanidine derivatives.

4. General formula (1) General formula [In the formula, R4b R5b R11, R? and R8 represents hydrogen, alkyl having 18 or less carbon atoms, cyclic alkyl, aryl, aralkyl, amino, alkyl, mino, 'r sylamino, carbamoylamino, or heterocyclic residue, and R9 represents lower alkylene, phenylene, alkylene%"02 , Sl
, 5% O, -NH- or l represents a single bond), and the aryl group in the formula has a substituent such as alkyl, alkoxy, nitro, acylamino, alkylamino group and halogen. Also included. ] The ratio of the color developer to the color development aid is preferably in the range of 1:0.1 to 10 (by weight).

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 general formula (v)s (-(■
) can be particularly preferably used.

(V) y,.

n In the formula, R8° and R□ are alkyl having 1 to 5 carbon atoms.

or alkoxyl, or oxyalkyl, benzyl, substituted benzyl, benzoyl, substituted benzoyl, phenyl group, hydrogen atom, etc., where Y and 2 are halogen atoms, alkyl having 1 to 5 carbon atoms, carboxyl, and 1 to 5 carbon atoms. represents an alkoxyl, nitro, acetoxy group, etc., m and n represent 0 or a positive integer of 4 or less.
r%So, , No, , PF, , Coo, ,
Anions such as BF, and further ZnC/2% COC
It represents an ion added to an anion such as l 2 or SnC/4.

Specific examples include 4-N,N-dimethylaminobenzenediazonium chloride, 3-chloro-,1-N,N-diethylaminobenzenediazonium chloride, 4-N,N
-diethylaminobenzenediazonium chloride, 2,
5-Jethoxy-4-N, N-diethylaminobenzenediazonium chloride, 4-N-ethyl-N-hydroxyethylaminobenzenediazonium chloride, 4-N
, N-jethoxyaminobenzenediazonium chloride, 4-phenylaminobenzenediazonium chloride,
Examples include 4-N-(P-methoxyphenyl)-aminobenzenediazonium chloride.

(Vl) ”- n In the formula, R12 is -CH2CH20CH2CH, - or -CH
20CII2CH2-, -CH2CH2CH2CH,-
etc. X, Y.

Z, m and n have the same meanings as in general formula (V).

Specific compound examples include 4-morpholinobenzenediazonium chloride, 2,5-jethoxy-4-morpholinobenzenediazonium chloride, 4-oxacyridinobenzenediazonium chloride, 3-methyl-4-
Examples include piperidinobenzenediazonium chloride.

゛ni□ In the formula, R represents an alkyl group or an aryl group.

Moreover, X%Y, Z, m and n have the same meanings as in the case of general formula (V).

Specific compound examples include 4-ethylmercapto-2,
5-Jethoxybenzenediazonium chloride, 4-tolylmercapto-2,5-miraethoxybenzenediazonium chloride, 4-pendylmercapto-2,5
-Dimethoxypene, vinylazonium chloride, etc.

These diazonium salts are dissolved in water or an organic solvent, or dispersed in fine particles in a suitable solvent, preferably at 0°C.
It can be applied to the support-1 within the range of 1 to X, 0fI-//.

In order to stabilize the diazonium salt and prevent pre-coupling, an acid compound is used in the photosensitive and heat-sensitive layer (S can also be used, but this is an organic or inorganic acid compound used in conventionally known diazo type copying materials). Any compound can be used, and specific examples include tartaric acid, citric acid, boric acid, lactic acid, merconic acid, phosphoric acid, trichloroacetic acid, dichloroacetic acid, cyanoacetic acid, oxalic acid, malonic acid, maleic acid, etc. Both are preferably used.

These acid compounds are preferably used in a weight ratio of 5.0 to 100%, more preferably 10 to 50%, based on the organic basic compound.

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, oxynaphthalene derivatives, compounds containing active methylene groups, hederocyclic compounds, etc. Specific examples of these compounds include the following compounds.

Phenol derivative pyrocatechol resorcin phlorglycine pyroga p-rumethaminophenol paraaminophenol diethylaminophenol N-lauryl-varaminophenol N-7 sil-metaaminophenol 3,3',5-trihydroxydiphenyl 3,3
'5,5'-Tetrahydroxydiphenyl α-resorcinic acid β-resorcinic acid r-resorcinic acid Prologlucinic acid gallic acid Oxynaphthalene derivative 2,3-dihydroxynaphthalene β-naphthol α-naphthol 1,6-dihydroxy naphthalene 2,3-dihydroxynaphthalene-6-sulfonic acid 2-
naphthol 3,6-disulfonic acid 1,8-dihydroxynaphthalene-8-sulfonic acid 2-
Hydroxy-3-naphthoic acid-N,N-bisβ-hydroxyethylamide 5-(balanitro)-benzamide-1-naphthol 2
-Hydroxy-3-propylmorpholinonaphtho: r. f
j@2-hydroxy-3-naphthoic acid-0-)luidide 2-hydroxy-3-naphthoic acid-4'-t10 anilide 2-hydroxy-3-naphthoic acid-5'-chloro-2'
.

4'-dimethoxyrnilide 2-hydroxy-3-naphthoic acid phenyl ester 2
-Hydroxy-3-nattokai-4'-phenoxyanilide 2-hydroxy-3-naphthoic acid-4'-'S-dyloxyanilidone Compound containing old methylene group 1-phenyl-3-methyl-pyrazolone G) acetoacetic acid anilide 1-7 Dissolve in water or organic solvent,
Alternatively, it can be contained in the heat-sensitive layer as a fine particle dispersion with a particle size of 10 μm or less using a dispersion means such as a ball mill or a sand grinder attritor.

Furthermore, two or more coupler compounds may be combined, if necessary, to produce a combination of dyes exhibiting desired spectral absorption characteristics.

Further, during dispersion, the coupler compound may be dispersed alone, but it may also be co-dispersed with an organic basic compound, the color development aid of the present invention, or other additives if necessary.

If the organic basic compound used as a color developer is soluble in the water or organic solvent used as a solvent for the coating solution when applied to the support, the pH of the coating solution will be low enough to prevent fogging on the upper gel surface and storage stability. It is desirable to exist as a discontinuous fine particle dispersion in the coating layer, and the
If the solubility at °C is 1.0i/j' or less, the storage stability under humidity and heat is good, and heterocyclic compounds such as aliphatic amines, pyrrolidine derivatives, imidazole derivatives, imidacillin derivatives, and piperidine derivatives are also suitable for use. However, when the following general formula values) and (2) hydrophobic guanidine derivatives are used as color developers, fixed heat-sensitive recording materials with excellent storage stability under high temperature and high humidity conditions and color development with high sensitivity can be obtained. You can get a body. Also, the color developer has a melting point of 100 = 170
℃ range can be particularly preferably used.

The color developer is a ball mill or sand grinder.

Although it may be dispersed independently using a dispersion means such as an attritor,
It is also possible to co-disperse the coupler compound, the color development aid of the present invention, or other additives as necessary.

General formula (1) General formula (IT) [In the formula, R4s R5s R6s R7 and R11 are hydrogen, alkyl having 18 or less carbon atoms, cyclic alkyl, γ-aryl, aralkyl, amino, alkylamino, acylamino, carbamoylamino, ? 1J7 element Jζ゛1 residue, R1 is lower alkylene, phenyl/7, lower alkylene, SO2, S2. S,0,-Nil-J':
(represents a double bond), and the aryl group in the formula includes those having a substituent selected from lower alkyl, alkoxy, nitro, acylamino, alkylamino groups, and norogen. An example is shown in Table 3, which represents a cyclohexyl group.

Table-3 (1) H H u (4) (24) (26) . , 1 do\. H3 (Tomo) CM, C0-NH 1 N) I2-C-Nu.

(34) (35) 1 Nil, -C-NH.

<, 16) (37) These guanidine derivatives shown above can be easily synthesized by a known method or a method similar thereto.

In addition, binder materials for forming the photosensitive and heat-sensitive layer of the present invention include aqueous solvents such as cornstarch, gum arabic, glue, gelatin, casein, methylcellulose, ethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, and polyacrylamide.

Starch or modified products and derivatives thereof such as carboxymethyl starch, dialdehyde starch, polyvinyl alcohol or modified products and derivatives thereof, polyvinylpyrrolidone, imbutylene-maleic anhydride copolymer, polyacrylate, styrene-maleic anhydride Copolymer, poly JJ Daika Vinyl, polyvinylidene chloride, polystyrene,
Synthetic resin emuldigons such as styrene butadiene rubber (=SBR), methacrylate butadiene rubber (=MBR), nitrile butadiene rubber (=NBR), polymethyl methacrylate, polypropylene, polyacrylonitrile, acrylic ester, etc. Binder materials can be used alone or in combination. Furthermore, in the case of an organic solvent system, the above-mentioned synthetic resin can be used by dissolving it in an organic solvent without emulsifying it.

Since the coupling reaction of diazonium salts is promoted in polar solvents such as water, the storage stability of fixed thermosensitive recording materials using diazonium salts, especially under high temperature and high humidity conditions, is limited by binder materials with low equilibrium moisture content. In addition, when using an aqueous solvent, ordinary water-soluble polymeric solvents such as formalin, glyoxal, chromium alum, geltaraldehyde, melamine/formalin resin, urea/formalin resin, etc. It is also possible to improve storage stability by using a water-resistant agent that is used in powder materials.

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 resin particles, calcium carbonate, aluminum hydroxide, magnesium hydroxide, magnesium carbonate, Titanium oxide, barium carbonate, urine purple - formalin fluoride
Qi, cellulose filler. Examples include aluminum oxide, but from the viewpoint of thermal head matching properties such as scum and sticking, JP-A-53-118059.54 25
54-118847 to 845.54-11111141
The oil absorption as described in the publication is 1) ml-500ml/100 according to the measurement method specified in JISK5101! i'
It is desirable to use oil-absorbing pigments such as those described above, and especially in the layer that comes into direct contact with the thermal head, it is desirable to use the oil-absorbing face 11 showing the above-mentioned oil-absorbing bones with calcined kaolin, urine-formalin filler, etc. .

As other auxiliary ingredients, color development suppressing agent "15 (('
Zinc chloride, zinc sulfate, sodium citrate, guanidine thiourea sulfate, calcium gluconate, and sugars such as sorbitol and sucrose are used to trap r.
If necessary, UV rainproofing agents may be added, or metal soaps may be used to improve sticking and color sensitivity.
I can do it.

These can be used alone as dispersed, but they can also be used as co-dispersed with an organic basic compound, a coupler compound, etc., or the color development aid of the present invention.

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 by exposure after thermal printing may decrease. Humid silica sol,
A light and heat sensitive layer may be applied after pre-sooting with a porous photosensitive agent such as alumina, titanium oxide or kaolin, or a combination of these and a polymeric material such as starch, casein, polyvinyl alcohol or polyvinyl acetate emulsion.

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

Example 1 A coating solution for a light and heat sensitive layer was prepared with the following formulation and coated on a support after drying. The fixing type heat-sensitive recording material was prepared using the following compositions: 7j; - Lumil, 48
After time pulverization and dispersion, i+, "a" was removed.

Solution A Solution B 11 Example 2 A fixable heat-sensitive recording material was prepared in the same manner as in Example 1 except that stearamide was used instead of ethylene bisstearamide in Solution A in Example 1.

Jt; ilj < 1 row 1° A fixing type heat-sensitive recording material was prepared in the same manner as in Example 1 except that ethylene bisstearamide was removed from Liquid A in Example 1.

Comparative Example 2 A fixable heat-sensitive recording material was prepared in the same manner as in Example 1 except that liquid B was not added.

The fixing type heat-sensitive recording material thus obtained was subjected to heat-sensitive printing using a facsimile (Toshiba KB-4800)', and the entire surface was exposed to ultraviolet light, and the diazo results are shown in Table 4. Table 4 also shows the results of the storage stability test. The storage stability test shows the results of a humidity and heat resistance test when a sample was prepared by preparing a coating solution, applied and dried, and left in a dark place at 40℃ and 90% relative humidity for 24 hours. After the test, the entire surface was exposed to light and fixed. Table 4 shows the skin density measured at the n-th Macbeth density.

Table 4 Example 3 A layer containing a diazonium salt was prepared with the following formulation, and the coating amount after drying on the support was 2.5y-/i on the layer prepared above. The coating liquid of the layer containing the color developer prepared according to the formulation was applied so that the coating amount after drying was 8.5 P//, fixed type heat sensitive, and 50% melamine-formalin-based liquor resistance agent 2y. , A liquid, and B liquid had the same formulation as in Example 1. They were prepared by grinding and dispersing in a ball mill for 48 hours.

Example 4 In Example 3, the procedure was the same as in Example 3 except that the composition of liquid A and liquid B was the same as in Example 2. ′? I created a type Kankyu record.

Comparative Example 3 A 4'1 type thermal recording material was prepared in the same manner as in Example 3, except that the composition of liquids A and B was the same as in comparative example 1.

Comparative Example 4 A fixing type thermosensitive recording material was prepared in the same manner as in Example 3 except that the composition of liquid A was the same as in Example 1 and liquid B was omitted.

The thus obtained diazo-fixed heat-sensitive recording material was subjected to heat-sensitive printing using a facsimile machine (Toshiba KB-48 (10)), and the entire surface was exposed to ultraviolet light to decompose and fix the diazonium salt.

The printed density test meter (R
D-514) and the values are shown in Table-5.

Table 5 also shows the results of the storage stability test.

The storage stability test was a humidity and heat resistance test in which the coating solution was prepared, applied and dried, and the formed sample was left in a dark place at 40°C and 90% relative humidity for 24 hours. Table 5 shows the results of the 1...I heat test where the samples were left to stand, and the background densities measured with a Macbeth densitometer after being treated and fixed by exposing the entire surface to light.

Table-5

Claims (1)

[Scope of Claims] 1. Diazonium salts, coupler compounds, coloring aids, and complexing agents containing fine particulate molecules of organic basic compounds that exhibit a basic atmosphere when melted by heat in the same layer or in two or more layers. In a fixing type heat-sensitive recording material provided on a support as a light- and heat-sensitive layer consisting of another layer, the coloring aid is expressed by the following general formula (
A fixable thermosensitive recording material characterized by being a fatty acid amide derivative represented by υ or (1). General formula (I) R1COtJIIR2 General formula (I) R8CONH(CH2)nNHCOR. In the formula, R1% R3 is a saturated or unsaturated alkyl group having 4 to 26 carbon atoms sR1 is a hydrogen atom and 1 to 8 carbon atoms. A2.
2 groups, 7 x = /I/ groups 1, 2 degrees a2. Ya 9 groups n
indicates an integer of 1.2 or 3. 2. The fixable heat-sensitive recording material according to claim 1, wherein at least one of the diazonium salt and the coupler compound is contained in the light- and heat-sensitive layer as a discontinuous fine particle dispersion. 34. The fixable heat-sensitive recording material according to claim 1 or 2, wherein the organic basic compound is a hydrophobic guanidine derivative represented by the following general formula value) or (2). General formula (phantom general formula @) [In the formula, R4b R8k R# % R7 and R8 represent hydrogen, carbon carbamoylamino, or a heterocyclic residue, and it. is lower alkylene, phenylene, naphthylene or SO□s
, , s% O, -Nu- or -does not represent a double bond), and the aryl group in the formula has a substituent selected from lower alkyl, alkoxy, nido p1 acylamino, alkylamino group, and l.logen. Also included. ]