JPS61199983A - Multicolor-forming type thermal recording material - Google Patents

Abstract

PURPOSE:To obtain a multicolor type thermal recording material excellent in the storability of recordability before printing and the stability of recording after printing by providing specific micro capsules, a specific developer, a specific coupler, and a specific decolorizer on the same side of a supporter. CONSTITUTION:A micro capsule with core containing colorless or light-color base dye precursor and a developer to cause color-forming reactions with the dye precursor, or a micro capsule with core containing an acid dye precursor and a developer to cause color-forming reactions with the acid dye precursor, a micro capsule with core containing a diazo compound and a coupler to cause color-forming reactions with the diazo compound, and a decolorizer for colorant formed from reactions of the base dye precursor with the developer or for colorant formed from reactions of the acid dye precursor and the developer are provided on the same side of a supporter to obtain a desired multicolor type thermal recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a multicolor recording material, which has particularly excellent storage stability before thermal recording and recording stability after thermal recording.
Furthermore, the present invention relates to a heat-sensitive recording material that has a high color density upon thermal recording.

"Prior art" As a multicolor heat-sensitive recording material, for example, colorless or light-colored 7
A phenolic color-forming substance, a phenolic substance that is solid at room temperature that reacts with the phenolic color-forming substance when heated, a basic substance that is solid at room temperature, and a color-forming property that develops color by reacting with the basic substance when heated. A multicolor color-forming heat-sensitive recording material containing a combination of dispersions of each substance is special! /-J7J-4-.

The heat-sensitive recording material takes advantage of the difference in melting point between a 7-enol substance that is solid at room temperature and an organic base that is solid at room temperature, and when the phenolic substance melts during heating, a coloring reaction occurs with the phenolic substance (crystal violet lactone). When a color-forming substance (such as In addition to fading or erasing the color when the base is present, the base causes the color-forming substances that can develop a different color to develop, thereby selectively melting each color-forming substance depending on the heating temperature and causing a color-forming reaction. It is a multicolor thermosensitive recording material that develops colors.

The multicolor heat-sensitive recording material is manufactured by first bleaching the colored phenolic coloring substance with an organic base, and then causing the coloring substance capable of coloring to be colored by the basic substance.
It is a sign.

Generally, a basic dye precursor (leuco dye) colored thermosensitive recording material is used as a recording material used in a thermal recording method, but it is generally known that the color of the leuco dye fades or disappears when exposed to a base. Therefore, it is easy to imagine the decoloring carried out in the heat-sensitive recording material. The most important feature of this heat-sensitive material is that the organic base added for decolorization is used not only for decolorization but also for the development of other colors. However, in order to obtain multiple colors, a dye that develops color by reacting with a base is essential, and the range of color-forming materials that can be used is extremely limited, which greatly limits the design and manufacture of recording materials. In addition, since color-forming substances and basic substances are contained in a dispersed state in close proximity to each other in the same layer, sweat from hands or oily substances may adhere to them during handling before or after recording, and adhesive tape, diazo copying paper, acid or Undesirable decolorization when in contact with base vapors,
It has the disadvantage of causing color development.

"Problems to be Solved by the Invention" Therefore, the first object of the present invention is to provide a multicolor heat-sensitive recording material that has excellent storage performance of recording performance before printing and stability of recording after printing. It is in. A second object of the present invention is to provide a multicolor heat-sensitive recording material that can produce multiple colors through simple heat recording.

A third object of the present invention is to provide a multicolor heat-sensitive recording material with excellent manufacturing suitability.

"Means for Solving the Problem" As a result of intensive research, the present inventors discovered microcapsules containing a colorless or light-colored basic dye precursor in the core, and a color developer that causes a color-forming reaction with the basic dye precursor. , or microcapsules containing a colorless or light-colored acidic dye precursor in the core and a color developer that causes a coloring reaction with the acidic dye precursor, and microcapsules containing a diazo compound in the core and a coloring reaction with the diazo compound. A coupling agent produced, and a dye produced by a color-forming reaction between the basic dye precursor and a color developer that causes a color-forming reaction with the basic dye, or a color-forming reaction between the acidic dye precursor and the acidic dye precursor. This was achieved using a multicolor color former type heat-sensitive recording material, which is characterized by having a color erasing agent for the dye produced by the color reaction with a color developer on the same side of the support.

Typical examples of the multicolor development mechanism of the present invention will be outlined below.

Microcapsules containing a colorless or light-colored basic dye precursor or acidic dye precursor in the core, a color developer that causes a color reaction with the basic dye precursor or acidic dye precursor, and a diazo compound in the core. A coupling component that causes a color-forming reaction with the diazo compound, and a base or acid as a decolorizing agent, or a microcapsule containing the base or acid in the core, are provided on the same surface of the support. The glass transition temperature of the microcapsule wall containing the diazo dye in the core is made higher than the glass transition temperature of the microcapsule wall containing the basic dye precursor or the acidic dye precursor in the core. In addition, the melting temperature of the base or acid that is a color erasing agent or the glass transition temperature of the microcapsule wall containing the base or acid in the core can be determined by adjusting the melting temperature of the base or acid that is the decolorizing agent or the glass transition temperature of the microcapsule wall containing the basic dye precursor or acidic dye precursor in the core. Higher than the glass transition temperature of the wall. When heat is applied to the heat-sensitive layer and the temperature of the microcapsule wall containing a basic dye precursor or acidic dye precursor in the core reaches around its glass transition temperature, the microcapsule wall becomes transparent. , the basic dye precursor or acidic dye precursor reacts with a color developer to develop color.

As the temperature is further increased, when the base or acid used as a color erasing agent exceeds its melting temperature, or when the microcapsule wall containing a large amount of base or acid in its core reaches around its glass transition temperature, the base or acid as a decolorizing agent reaches its glass transition temperature. Or, because the acid microcapsule wall becomes permeable and the environment around the decolorizing agent changes to basic or acidic - the color-carrying dye created by the basic dye precursor or acidic dye precursor fades or disappears. . Regarding the combination of a dye and a color erasing agent, in the case of a basic dye precursor, a base is used as the color erasing agent, and in the case of an acidic dye precursor, an acid is used as the color erasing agent.

On the other hand, when the temperature reaches or exceeds the temperature at which the above-mentioned decolorizing agent acts, the microcapsule wall containing the diazo compound in its core reaches around its glass transition temperature, and the microcapsule wall becomes permeable and the diazo compound and cup The ring agent reacts and develops color.

A multicolor thermosensitive recording device that develops colors in different hues at low and high temperatures by incorporating components that develop different hues into the low-temperature microcapsules containing the basic dye precursor or acidic dye precursor and the high-temperature microcapsules containing the diazo compound. Materials are obtained. Note that the melting point of the decolorizing agent or the glass transition temperature of the microcapsule wall containing the decolorizing agent in the core does not need to be between the glass transition temperature of the low-temperature microcapsule wall and the glass transition temperature of the high-temperature microcapsule wall. It may be the same as or higher than the glass transition temperature of the high temperature microcapsule wall. In the former case, the low-temperature microcapsules develop color at low temperatures, and the high-temperature microcapsules develop color simultaneously with fading or erasure of the color at high temperatures.

In the latter case, color development by the low temperature microcapsules occurs at low temperatures, and color development by the high temperature microcapsules occurs on top of the color development by the low temperature microcapsules at high temperatures, resulting in color mixing. When the temperature is further increased, the color developed by the low temperature microcapsules fades or disappears due to the decolorizing agent, so that the color developed by the high temperature microcapsules remains.

In either case, a multicolor heat-sensitive recording material that develops different hues at low and high temperatures can be obtained.

One of the features of the present invention is that until the microcapsule wall is heated, it functions to prevent contact between a component that causes a coloring reaction and another component that reacts with the component that causes the coloring reaction to develop a color. By using two or more types of microcapsules having different glass transition temperatures, the temperature at which the coloring reaction and coloring reaction occur can be controlled.

Therefore, it has the following remarkable features compared to conventional thermal paper.

(1) Handling before and after recording, adhesive tape, diazo copy paper,
It has the effect of preventing undesirable discoloration or color development when it comes into contact with acid or base vapor.

This is because the walls of the microcapsules have extremely good barrier properties at temperatures below the recording temperature.
This is because even if some or all of the color developer and decolorizer come close to each other in a liquid or gaseous state for some reason, they cannot come into contact with the dye before coloring or the pigment after coloring.

(2) Conventional color erasing agents cannot be effective at the initial color development temperature, so only solids with a fairly high melting point can be used. However, in the present invention, this is not necessarily necessary. For example, the color erasing agent can be If it is contained in a capsule, it can be used in liquid form, and a wide range of materials can be selected depending on the purpose.

When a solid color erasing agent is encapsulated in microcapsules, the melting point of the color erasing agent may be higher than the glass transition temperature of the microcapsule wall, but it is preferably lower.

In the present invention, the glass transition temperature of the microcapsule wall containing the diazo compound, the melting point of the decoloring agent and/or the decoloring The glass transition temperature of the microcapsule wall containing the agent is not limited as long as it is high, but it is generally 7100 or higher, preferably 2!0.
It is sufficient if there is a temperature difference of 0 or more, particularly preferably Jj'C or more.

The microcapsules of the present invention are ruptured by heat or pressure, as used in conventional recording materials, to bring the reactive substance contained in the core of the microcapsule into contact with the reactive substance outside the microcapsule. Rather than causing a color reaction, it permeates through the microcapsule wall and causes a reaction by heating the reactive substance present in the core and outside of the microcapsule. Until now, it has been known that when microcapsule walls are formed by a polymerization method, they do not become completely impermeable membranes but are permeable. The permeability of the microcapsule wall has been known as a phenomenon in which low-molecular substances gradually permeate over a long period of time, but a phenomenon in which low-molecular substances permeate instantaneously due to heating, as in the present invention, has not been known. Therefore, the microcapsule walls of the present invention do not necessarily need to be melted by heat. Rather,
It is preferable not to melt from the viewpoint of protecting the dye after color development.

Particularly good results are obtained when using synthetic resins such as polyurea, polyurethane, polyester, polyamide, urea-formalin resin, or a mixture thereof as the capsule wall material.

Capsule walls can be created by encapsulation by polymerizing actant from inside oil droplets, or by polymer precipitation, which provide dense walls, excellent storage stability, and easy control of capsule size and wall thickness, making it possible to create desirable capsules. Obtainable.

In this case, since the capsule contains a solvent, it is advantageous for the coloring reaction.

The present inventors have discovered that the thermal responsiveness of the microcapsules can be controlled arbitrarily by adjusting the material and film thickness of the microcapsule walls and additives such as color-forming reactants and color-forming aids existing outside the microcapsules. . The glass transition temperature of the capsule wall, which largely controls the thermal responsiveness of the present invention, is the glass transition temperature "as a system" including the effects of color-forming reactive substances, color-forming aids, and the like. That is, either the glass transition temperature itself is unique to the capsule wall, or the glass transition temperature is a state in which a substance outside the capsule is heated and melted during thermal printing, diffuses into the capsule wall, and causes interaction. The former method of controlling the glass transition temperature specific to the capsule wall is to change the type of capsule wall forming agent. In the case of polyurea, polyurethane, and polyurea/urethane capsules, it is particularly advantageous because the glass transition temperature can be varied widely by changing the type of incyanate used and by changing the type and amount of polyol and polyamine used together.

The glass transition temperature in the state where the latter interaction occurs can be changed by placing a glass transition temperature adjusting agent outside or inside the capsule.

This glass transition temperature is determined by the capsule wall or (capsule wall/
Color development aid outside the capsule) interactants with Pyblon ((
DDV-III model), manufactured by Toyo Baldwin Corporation), and refers to the peak temperature of TanJ, which is the dynamic loss modulus divided by the storage modulus.

The temperature at which thermal paper using capsules can develop color is determined when the glass transition temperature of the capsule wall "as a system" is determined.

The reason for this is that when the capsule wall changes from a glass state to a rubber state, substances diffuse between the inside and outside of the capsule and a coloring reaction occurs.

The capsule wall or the interaction product of the capsule wall and the heat-fusible substance to be subjected to the measurement of the glass transition temperature is prepared, for example, as follows.

20 parts of xylylene diisocyanate/trimethylolpronone (3:l adduct) as a capsule wall component was dissolved in 30 parts of ethyl acetate, coated on a polyethylene sheet, and reacted under water o-to-0c. After peeling, 2≠
Air dry for 7 days at 0C, 44'96R,H, 10-20
A polyurea film with a thickness of μ is obtained. This is the sample for measuring the glass transition temperature of the capsule wall alone. As a method for preparing an interaction product between a heat-fusible substance and a capsule wall, the above-mentioned polyurea film is immersed in a 20% methanol solution of p-benzyloxyphenol for 30 hours, and then
It can be obtained by air drying for one day at 0C1tlfi%R,H.

U.S. patents for microencapsulation methods and specific examples of compounds! , 726.10≠ No. 3, 7ri 4.
It is stated in the specification of No. AA.

For example, when polyurethane is used as a capsule wall material, polyvalent incyanate is mixed into the oily liquid to be encapsulated, emulsified and dispersed in water, and then the temperature is raised to cause a polymer formation reaction at the oil droplet interface. to form a microcapsule wall. At this time, a co-solvent with a low boiling point and strong dissolving power can be used in the oily liquid.

Also, a second material (such as a polyol) that reacts with the polyhydric incyanate to form the capsule wall can be used.

In this case, the polyisocyanate used and the partner polyol and polyamine that react with it are disclosed in U.S. Pat.
93Jtr No. 7, Tokuko Sho≠t-da O3≠7, μtar 2
Hiroshi/jri issue, JP-A-Shogu t-40/9/ issue, same p r-l
r+ o r +, and they can also be used.

Furthermore, tin salt or the like may be used in order to promote the urethanization reaction.

Examples of the polyvalent incyanate which is a wall film-forming substance in the present invention include m-phinyl diisocyanate,
p-722 diisocyanate, λ+t-t') diisocyanate, co,≠-tolylene diisocyanate, naphthalene-/, 44-diisocyanate, diphenylmethane-1, μ'-diisocyanate, 3,3'-dimethoxy-μ .

μ′-biphenyl diincyanate, 3.3′-dimethyldiphenylmethane-Hiroshi, Hiro′-diisocyanate,
Xylylene-/, 4! -Diisocyanate F, 4'vHiro'-diphenylpronone diisocyanate, trimethylene diinocyanate, hexamethylene diisocyanate, propylene-/, 2-diisocyanate, phthylene-/, J-diisocyanate, cyclohexylene-7, cordiisocyanate , diisocyanate such as cyclohexylene-71μm diisocyanate, μ, Hiro', ≠“-
Triphenylmethane triisocyanate, toluene-2
,4C,G-triisocyanate; There are incyanate solpolymers such as the adduct of ≠-tolylene diisocyanate and trimethylolpropane, the adduct of xylylene diisocyanate and trimethylolpropane, and the adduct of tolylene diisocyanate and hexanetriol.

Examples of the polyol that is the second wall-forming substance in the present invention include aliphatic and aromatic polyhydric alcohols, hydroxy polyesters, and hydroxy polyalkylene ethers. Preferred polyols include the following CI), (n), (DI) or (IV) between two hydroxyl groups.
Examples include polyhydroxy compounds having a molecular weight of 5,000 or less and having a group in the molecular structure.

(I) Aliphatic hydrocarbon group having carbon number λ to t (IV) 0-Ar-C-Ar -0-wherein,
Ar in (I), (1), and (IV) represents a substituted or unsubstituted aromatic moiety, and the aliphatic hydrocarbon group in (■) has -CnH2n- as its basic skeleton and other hydrogen groups. may be substituted with an element.

To give a specific example, examples of (■) include ethylene glycol, /, J--f lobanediol, l, Hiro-butanediol, /,! -bentanediol, l,t-hexanediol, l,7-hebutansinol, /,t-
Octanediol, propylene glycol, λ, 3-dihydroxybutane, /, λ-dihydroxybutane, /,
3-dihydroxybutane, Kodimeteru/,! −
Prono2 diol, tips 4/L-hantanediol,
λ, j-hexanediol, 3-methyl-7,! -bentanediol, / Hiro-cyclohexane dimetatool,
dihydroxycyclohexane, diethylene glycol,
/, 2. t-)rihydroxyhexane, phenylethylene glycol, i, t, i-trimethylolpropane,
Examples include hexanetriol, hantaerythritol, and glycerin.

Examples of (Il) include condensation products of aromatic polyhydric alcohols and alkylene oxides such as 12 μm di(λ-hydroxyethoxy)benzene and resorcinol dihydroxyethyl ether.

Examples of (1) include p-xylylene glycol, m-
Xylylene glycol, α, α′-dihydroxy-p-
Examples include diisopropylbenzene.

Examples of (IV) include ≠, ILL'-dihydroxy-
Diphenylmethane, '(p+p' ``hydroxydiphenylmethyl)benzyl alcohol, adduct of ethylene oxide to bisphenol A, bisphenol A
Examples include adducts of propylene oxide. The polyol is preferably used in a proportion of hydroxyl groups of 0.02 to λ mol per 1 mol of isocyanate groups.

Examples of the polyamine, which is another wall-forming substance of the present invention, include ethylenediamine, trimethylenediamine,
Tetramethylene diamine, huntamethylene diamine, hexamethylene diamine, p-7 22 diamine, m-
Phenylenediamine, piperazine, λ-methylpiperazine, λ,j-dimethylbi-radizine, co-hydroxytrimethylenediamine, diethylenetriamine, triethylenetriamine, triethylenetetramine, diethylaminopropylamine, tetraethylenepentamine, amine adducts of epoxy compounds, etc. can be given.

In the present invention, a reactive substance contained in the core material of a microcapsule is dissolved or dispersed in a water-insoluble organic solvent, emulsified, and then a microcapsule wall is formed in the resulting solution by polymerization. The organic solvent preferably has a boiling point of iro 0c or higher, such as phosphoric esters, phthalic esters, other carboxylic esters, fatty acid amides, alkylated biphenyls, alkylated terphenyls, chlorinated paraffins, alkylated naphthalenes, diarylethanes, etc. is used. Specific examples include tricresyl phosphate, trioctyl phosphate, octyldiphenyl phosphate, tricyclohexyl phosphate, dibutyl heptatalate, dioctyl phthalate, dilauryl heptathalate, dicyclohexyl phthalate, butyl oleate, diethylene glycol dibenzoate, Dioctyl zepacate, diptyl sepacate, dioctyl adipate, trioctyl trimellitate, acetyltriethyl citrate, octyl maleate, dibutyl maleate, isopropylbiphenyl, isoamyl biphenyl, chlorinated paraffin, diisopropylnaphthalene, diphenylethane/, /'- Ditolylethane, 2. l
I-Ditertiary aminophenol, N,N-dibutyl-λ-phthoxy! -Tertiary octylaniline and the like.

When making microcapsules, water-soluble polymers can be used.Water-soluble polymers include anionic polymers, nonionic polymers, and amphoteric polymers that are dissolved in water. , natural or synthetic ones can be used, and examples thereof include those having -COO-, SOi groups, etc. 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-based) polymers and copolymers, vinylbenzenesulfonic acid-based polymers and copolymers, Carboxy-modified polyvinyl alcohol.

Examples of nonionic polymers include polyvinyl alcohol, hydroxyethyl cellulose, and methyl cellulose.

Examples of amphoteric compounds include gelatin.

These water-soluble polymers are used as a 0.0/~iowt% aqueous solution.

Glass transition temperature modifiers that interact with the capsule and change the glass transition temperature "as a system" include, in particular, hydroxy compounds with a melting point of jO'C-170'C, carbamate esters, aromatic methoxy compounds, and organic sulfonamides. Compounds etc. are effective.

Specific examples of hydroxy compounds include p'-butylphenol, p-t-octylphenol, p-α-cumylphenol, methylphenol, m-xylenol, 2.j-dimethylphenol, co,≠,J-- 1-trimethylphenol, 3-methyl-≠-isopropylphenol, p-benzylphenol, 0-cyclohexylphenol, p(diphenylmethyl)phenol, p-
(α,α-diphenylethyl)phenol, 〇-phenylphenol, p-hydroxybenzoate ether, p-hydroxybenzoate furovir, ri-butyl hydroxybenzoate, p-hydroxybenzoate benzyl, p-methoxyphenol, p-butoxyphenol, p-hebutyloxyphenol, p-benzyloxyphenol, 3-
Dimethyl hydroxyphthalate, vanillin, l, l-bis(≠-hydroxyphenyl)dodecane, /, /-bis(
Hiroshi-hydroxyphenyl)-2-ethyl-hexane, l
, l-bis(4A-hydroxyphenyl)-comethyl-tantan, co, 2-bis(4A-hydroxyphenyl)
-hebutane, no(nilin, λ-t--f chiruhiro-no methoxyphenol.

7-phenol compounds such as 6-simethoxyphenol, co-, λ'-dihydroxy-Hiro-methoxybenzophenone,
-2j-dimethyl-2,j-hexanediol, resorcinol di(λ-hydroxyethyl) ether, resorcinol mono(-monohydroxyethyl) ether, f
') f Lua /I/: l-ru, /, 4<-di(hydroxyethoxy)benzene, p-xylylene diol, l-phenyl-/, 2-ethanediol, diphenylmethanol, /, l-diphenylethanol , λ-methyl-cophenylene/, j-propanediol, core 6
-dihydroxymethyl-p-cresol benzyl ether, λ, t-dihydroxymethyl-p-cresol benzyl ether, 3-(o-methoxyphenoxy)-/,
Examples include alcohol compounds such as J--10 nogundiol and the like. Specific examples of carbamate ester compounds include N-phenylcarbamate ethyl ester, N-phenylcarbamate benzyl ester, N-phenylcarbamate phenethyl ester, carbamate hensyl ester, carbamate phthyl ester, carbamate isopropyl ester, etc. can be mentioned.

Specific examples of aromatic methoxy compounds include λ-methoxybenzoic acid, 3. ! -dimethoxyphenylacetic acid, λ-methoxynaphthalene, /, J, j-) dimethoxybenzene,
Examples include p-dimethoxybenzene, p-benzyloxymethoxybenzene, and the like. Specific examples of organic sulfonamide compounds include p-toluenesulfonamide, benzenesulfonamide, and their rust conductors.

The amount of these compounds to be used varies depending on how much the glass transition temperature is changed, but the amount of these compounds used is 0.000% per part by weight of the capsule. /-
10 parts by weight, preferably 0. ! -~! Parts by weight are appropriate.

The basic colorless dye precursor used in the present invention includes:
For example, crystal violet lactone, 3-indolino-Jp-dimethylaminophenyl-t-dimethylaminophthalide, 3-diethylamine-7-chlorofluoran, J-diethylamino-7-cyclohexylaminofluorane, 3-diethylamine- ! -Methyl-7-1
-Butylfluoran, 3-diethylamino-4-methyl-7-anilite fluoran, 3-diethylamine-B-
Methyl-7-p-7'thylanilinofluorane,! −
(N-phenyl-N-ethyl)aminofluorane, 3-
diethylamino-7-dibenzylaminofluorane, 3
-cyclohexylamino-6-chlorofluorane, 3-
Diethylamino-t-methyl-7-xylidinofluorane, λ-anilino-3-methyl-j-(N-ethyl-p
-1luidino) fluorane, 3-pyrrolidino-t-methyl-7-anilite fluorane, 3-pyrrolidino-7-cyclohexylaminofluorane, 3-piperidi/-j-
Methyl-7-toluidinofluorane, 3-pyrrolidino-
t-Methyl-7-(p-toluidino)fluoran, 3-
Piperidino-4-methyl-7-anilite fluorane, 3
-N-methylcyclohexylamino-t-methyl-7-
Anilitufluoran, 3-diethylamino-7-(m-
) fluoromethylanilino) fluorane, etc., but are not limited thereto.

As acids used as color developers or decolorants for these color formers, phenol compounds, organic acids or metal salts thereof, oxybenzoic acid esters, etc. are used.

Particularly, a 7-enol having a melting point of 100 to 2j00C, particularly preferably g o O to 1000C, which is sparingly soluble in water,
Organic acids are preferred. Moreover, the temperature at which they melt is
When used as a color developer, it is preferably lower than the melting temperature of the color erasing agent used. Further, when used as a color erasing agent, it is preferably higher than the melting temperature of the color developer used.

Examples of phenolic compounds include ri, Hiro'-impropylidene diphenol (bisphenol A), I)
tert-butylphenol, λ, France-dinitrophenol, 3. p-dichlorophenol, Hiroshi, 3'-methylenebis(2,t-dite1t-y'thylphenol), p-phenylphenol, +,4t-cyclohexylidene diphenol, λ, λ'-methylenebis(≠ -te1t-butylphenol)1.2.
J'-methylenebis(α-7enyl-p-cresol)
Thiodiphenol, tei, ≠′-thiobis(≦-tert
-butyl-m-cresol), sulfonyldiphenol, /, l-bis(≠-hydroxyphenyl)-n-dodecane, Hiro, Hiro-bis(lI-hydroxyphenyl)-/
In addition to -suntanic acid ethyl ester, there are p-tert-butylphenol-formalin metal condensates, p-phenylphenol-formalin metal condensates, and the like.

Examples of organic acids or metal salts thereof include j-tert-butylsalicylic acid, J,j-tert-butylsalicylic acid, j-α-methylbenzylsalicylic acid, 3,j-di-α
-Methylbenzylsalicylic acid, 3-teft-octylsalicylic acid,! -α,r-dimethyl-α-phenyl-r
-7enylprobylsalicylic acid and the like and their zinc, lead, aluminum, magnesium, and nickel salts are useful.

Examples of oxybenzoic acid esters include ethyl p-oxybenzoate, butyl p-oxybenzoate, Hepdel p-oxybenzoate, and benzyl p-oxybenzoate.

The melting temperature in the present invention is the melting point when no eutectic compound is present, and the eutectic point when there is a eutectic compound in the same layer.

Examples of acidic dye precursors used in the present invention include phenolphthalein, fluorescein, co/,
4tl, 11,7/-tetrabromo-3,l.

! , t-tetrachlorofluorescein, tetrabromophenol blue, French, j, t, 7-titrabromophenolphthalein, eosin, alarin cresol red, 2-s7tolphenolphthalein, etc., but are limited to these. It is not something that will be done.

The diazo compound used in the heat-sensitive material of the present invention is a diazonium salt represented by the general formula ArN2+X-, which can develop a color by causing a coupling reaction with a coupling agent, and cannot be decomposed by light. It is a compound that can. (In the formula, Ar represents a substituted or unsubstituted aromatic moiety, N20 represents a diazonium salt, and X- represents an acid anion.) Specific examples of diazonium compounds that form salts include Hiro-Diazo- 7-dimethylaminebenzene, gudiazo-
l-diethylaminobenzene, μ-diazo-7-cypropylaminobenzene, μm diazo-7-methylbenzylaminobenzene, ≠-diazo/-dibenzylaminobenzene, Gudiazo-7-ethylhydroxyethylaminobenzene, Hiro-diazo- l-diethylamine-3-methoxybenzene, diazo-7-dimethylamino-2
-Methylbenzene, ≠-diazo/-benzoylamino-λ, j-jethoxybenzene, ≠-diazo l-morpholinobenzene, gudiazo-/-morpholinoco, j
-Jethoxybenzene, Hiro-diazo-7-morpholino-
λ,! -diphthoxybenzene, ≠-diazo 1-anilinobenzene, ≠-diazo/-)ruylmercap)-j
, , lt-jethoxybenzene, p-diazo/
, 4C-methoxybenzoylaminoco, j-jethoxybenzene, and the like.

Specific examples of acid anions include CnFzn+tCOO-
(n is an integer from 3 to 2), CmF2m+xSOs-(m
is an integer from 2 to r), (CIFzl+xSOz)2CH
- (1 is an integer of /-/r), H (n is an integer of 3 to 3) (n is an integer of 3 to 2) B F 4- , P F s-, and the like.

In particular, among the acid anions, those containing an R-fluoroalkyl group or perfluoroalkenyl group or PF
5- is preferable because it causes less increase in fog during raw storage.

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

C4H9 C4H9 C4Hg QU4H9 The coupling agent used in the heat-sensitive recording material of the present invention is one that forms a dye by coupling with a diazo compound (diazonium salt) in a basic atmosphere, and specific examples include resorcin, 70 loglucin, λ, Sodium 3-dihydroxynaphthalene-sulfonate, l-hydroxy-sulfonate morpholinopropylamide, I
, j-dihydroxynaphthalene, co,3-dihydroxynaphthalene, λ, 3-dihydroxy-6-sulfanylnaphthalene, λ-hydroxy-3-naphthoic acid morpholinopropylamide, -monohydroxy-3-naphthoic acid anilide, λ-hydroxy-3-naphthoic acid Acid-2'-methylanilide, -monohydroxy-3-naphthoic acid ethanolamide, λ-hydroxy-3-naphthoic acid octylamide, 2-hydroxy-3-naphthoic acid-N-dodecyl-oxy-propylamide, cohydroxy-3 -su7
Toic acid tetradecylamide, acetanilide, acetoacetanilide, benzoylacetanilide, l-phenyl-3-methyl-iohirazolone, i-(λ' ?≠l
, t/-trichlorophenyl)-3-benzamide-
Yo-pyrazolone, /-f2'.

μ/, A/ )lichlorophenyl)-3-anili/
-1-pyrazolone, l-phenyl-3-phenylacetamido-3-pyrazolone, and the like.

As the basic substance used as a decolorizing agent and a coupling reaction aid for the heat-sensitive recording material of the present invention, a basic substance that is sparingly soluble or insoluble in water or a substance that generates dialkali when heated is used.

Basic substances include inorganic and organic ammonium salts, organic amines, amides, urea and thiourea and their derivatives, thiazoles, pyrroles, pyrimidines, piperazines, guanidines, indoles, imidazoles, imidacillins, and triazoles. Examples include nitrogen-containing compounds such as morpholines, pyridines, amidines, formazines, and pyridines. Specific examples of these are:
For example, ammonium acetate, tricyclohexylamine,
Tribenzylamine, octadecylbenzylamine, stearylamine, allyl urea, thiourea, methylthiourea, allylthiourea, ethylenethiourea, copendylimidazole, l-phenylimidazole, copheny-4'-mef-imidazole, --undecyl-imidacillin ,λ,≠,j-trifuryl-imidazoline,/.

λ-diphenyl-Hiro, ≠-dimethyl-11-imidazoline, 2-phenyl-coimidazoline, /12, J-triphenylguanidine, l, 2-ditolylguanidine, l
, λ-dicyclohexylguanidine, /, 2-dicyclohexyl-3-722ruguanidine, 't't')! J
Cyclohexylguanidine, guanidine trichloroacetate, N.

These include N'-dibenzylpyrazine, di-hiro'-dithiomorpholine, morpholinium trichloroacetate, co-aminobenzothiazole, and λ-penzoylhydrazinopenzothiazole. Two or more of these basic substances can also be used in combination.

In order to prevent the diazo compound used in the present invention from yellowing due to light, a vinyl compound can be contained in the microcapsules containing the diazo compound.

The vinyl compound is a compound having one or more vinyl or vinylidene groups, preferably a plurality thereof, and includes, for example, compounds having an acryloyl group, a methacryloyl group, an allyl group, an unsaturated polyester group, a vinyloxy group, an acrylamide group, and the like.

The most typical examples include reaction products of polyols, polyamines, amino alcohols, etc., and unsaturated carboxylic acids, and reaction products of acrylates or methacrylates having hydroxyl groups and polyisocyanates.

For example, representative compounds include polyethylene glycol diacrylate, propylene glycol dimethacrylate, pentaerythritol triacrylate, trimethylolpropane diacrylate, trimethylolpro7centriaacrylate, and intererythritolnato2.
Acrylate, hexanediol diacrylate, /
2-butanediol diacrylate, tetrakis β-acryloxyethylethylene diamine, reaction product of epoxy resin and acrylic acid, reaction product of methacrylic acid, antaerythritol and acrylic acid, condensation product of maleic acid, diethylene glycol and acrylic acid, These include methyl methacrylate, butyl methacrylate, styrene, divinylbenzene, and diarylnaphthalene. A plurality of these can be used in combination depending on the purpose.

□The amount of the compound used in the present invention is Q for the basic dye precursor, acidic dye precursor, and diazo compound, respectively.
Oj~/,! P/rIL2, preferably 0, Oj-
0, r Ji / door 2, color developer of basic dye precursor or acidic dye precursor, coupling agent is 0.3~
rP/m2, preferably o, z~zy/pain 2, and the decolorizing agent is 0. J~loy/m2, preferably /~j7m
2, the organic solvent encapsulated in the microcapsules is θ,
/~l! 7 m2, preferably 0,/-! r
f/71! It is 2.

When a vinyl compound is contained in a microcapsule containing a diazo compound, the organic solvent encapsulated in the microcapsule can be substituted with the vinyl compound in any proportion. In addition, when using a basic substance for the purpose of promoting the coloring reaction of the diazo compound, o, 3~ry/m2
, preferably 0. j〜j y / 71! 2 can be used. The decolorizing agent may be present in an amount equal to or more than the mole of the color developer and the color accelerator of the diazo compound;
It is preferable to use twice the molar amount.

The basic dye precursor or acidic dye precursor and diazo compound used in the present invention are each encapsulated in microcapsules, but the color developer and decolorizing agent, or the color development accelerator of the diazo compound used if necessary, are encapsulated in separate microcapsules. You may. When not encapsulated in microcapsules, it is preferable to use a solid dispersion using a sand mill or the like. Preferred water-soluble polymers include water-soluble polymers used when making microcapsules.

As for the layer structure of the heat-sensitive material of the present invention, one heat-sensitive layer may be provided, and < indicates a multi-layer structure. Further, an intermediate layer can be provided between the heat-sensitive layer and the support, or between the heat-sensitive layers when multiple heat-sensitive layers are provided.

A protective layer can be provided on the surface of the heat-sensitive layer.

In the case of a multilayer structure, simultaneous multilayer coating is also possible in addition to sequential coating one layer at a time.

The heat-sensitive recording material of the present invention contains silica, barium sulfate, titanium oxide, aluminum hydroxide, zinc oxide,
Pigments such as calcium carbonate, fine powders such as styrene beads, urea-melamine resin, etc. can be used.

Similarly, metal soaps can also be used to prevent sticking. The amount of these used is 0.
λ~7y/m2.

The heat-sensitive layer, intermediate layer, and protective layer of the heat-sensitive recording material of the present invention can be coated using a suitable binder.

As a binder, polyvinyl alcohol, methyl cellulose, carboxymethyl allulose, hydroxypropyl cellulose, gum asybia, gelatin, polyvinylpyrrolidone, casein, styrene-butadiene latex, acrylonitrile-butadiene latex, polyvinyl acetate, polyacrylic acid ester, ethylene-acetic acid Various emulsions of vinyl copolymers can be used. The amount used is 0.1-1 solids/WL2.

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

The heat-sensitive recording material of the present invention can be prepared by dispersing the microcapsules and other components in a solid state or by dissolving them in an aqueous solution and mixing them to prepare a coating solution, and applying the solution on a support such as paper or a synthetic resin film using a per-coating method. Blade application, air knife application, gravure application, roll coating application, spray application,
After coating and drying using a coating method such as dip coating, the solid content is 2.
! A heat-sensitive layer of ~10 y/m2 is provided.

The paper used for the support is a thermally extracted paper sized with a neutral sizing agent such as an alkyl ketene dimer.
It is advantageous in terms of storage stability over time to use neutral paper of 4 to 4 (described in JP-A-Sho!!-/4!2ri).

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, Japanese Patent Application Laid-Open No. 7-11T
(Metric basis weight) 2 and Beck smoothness as described in tr711c? Papers of O seconds or more are advantageous.

In addition, paper with an optical surface roughness of t μ or less as described in λ of JP-A Sho Jlr-13t'A and a thickness of ≠θ~7jp, and a paper with a density of 0.21/ on 3 or less and paper with optical contact group of 7% or more, JP-A-Shorr-+
The Canadian standard water level (J Engineering S Pjl-
21) and 4! oocx, paper made from pulp that has been beaten as described above to prevent penetration of coating liquid, JP-A-Shoyo t-
atgri! JP-A-Sho!, which improves the color density and resolution by using the glossy side of base paper made by a Yankee machine as the coating surface, as described in JP-A-Sho! Ta 3! Rit! The paper described in 2007, in which the base paper is subjected to corona discharge treatment to improve the applicability of the coating, can also be used in the present invention and gives good results. In addition to these, any support commonly used in the field of heat-sensitive recording paper can be used as the support of the present invention.

The heat-sensitive recording material of the present invention can be used as recording paper for facsimile IJ and computer printers, electrocardiograms, recorders, etc., which are capable of multicolor recording and require high-speed recording, and after heating printing, it can be exposed to light to form capsules. It can be fixed by photocuring to inactivate it or by decomposing the unreacted diazo compound. In addition, it can also be used as a heat-developable copying paper.

Examples are shown below, but the present invention is not limited thereto. Note that "parts" indicating the amount added represent "parts by weight."

Example 1 [Capsule liquid A] The following basic colorless dye precursor ≠ part and (j:/) adduct of xylylene diisocyanate and trimethylolpropane/1 part were mixed with λ≠ part of diphenylethane and 3 parts of ethyl acetate. It was added to a mixed solvent and dissolved. A solution of this basic colorless dye precursor was mixed with 1.2 parts of polyvinyl alcohol and water.
The mixture was mixed with an aqueous solution in which the particles had been dissolved, and emulsified and dispersed at 20°C to obtain an emulsion with an average particle size of 3 μm. IOO parts of water was added to the obtained emulsion, and heated to 0.0C while stirring, and after 2 hours, microcapsule liquid A containing the following basic colorless dye precursor in the core was obtained.

(Basic colorless dye precursor) (Capsule liquid B) The following diazo compound λ part and xylylene diisocyanate and trimethylolprono ξ7(7) (J:/) adduct i
Part t was added to a mixed solvent of 7 μ parts of dibutyl talate and 5 parts of ethyl acetate and dissolved. This solution of diazo compound is
It's polyvinyl alcohol.

Mix in an aqueous solution in which 2 parts are dissolved in jr parts of water, 20
0 (:) to obtain an emulsion with an average particle size of 3 μm. To the obtained emulsion was added 100 parts of water, and while stirring,
After 2 hours, microcapsule liquid B containing a diazo compound in the core was obtained.

(Diazo compound) [Dispersion A] 70 parts of bisphenol A was added to 100 parts of an aqueous polyvinyl alcohol solution and dispersed for about 2 hours using a sand mill to obtain a dispersion A of bisphenol A having an average particle size of 3 μm.

[Dispersion B]

70 parts of the following compound! The mixture was added to 100 parts of the aqueous polyvinyl alcohol solution and dispersed in a sand mill for about 2≠ hours to obtain a dispersion B of a red color-forming coupling agent having an average particle size of 3 μm.

Compound [Dispersion C] / Kodicyclohexyl-3-phenylguanidine 1
0 part was added to 100 parts of a JCS polyvinyl alcohol aqueous solution and dispersed in a sand mill for about 2 hours to obtain a dispersion C of /,2.3-)riphenylguanidine with an average particle size of 3 μm.

[Dispersion D]

10 parts p-benzyloxyphenol,'sde
The mixture was added to 100 parts of an aqueous solution of ribinyl alcohol and dispersed in a sand mill for about λμ hours to obtain a dispersion of p-benzyloxyphenol with an average particle size of 3μ.

25 parts of capsule liquid A obtained as above, dispersion liquid A
Coating liquid A was prepared by adding lj part and Dlj part.

Next, part of the capsule liquid BJo and part of the dispersion liquid Bxo were added to prepare a coating liquid B. Further, the dispersion liquid C was used as a coating liquid C. Coating liquid A, coating liquid B, and coating liquid C were coated on smooth high-quality paper (0%
A heat-sensitive recording material was obtained by sequentially coating B, C, and A in the order of F/y12 on a dry weight basis of 9/m2) and drying each layer for 30 minutes. In Coating Solution A, the glass transition temperature of the capsule was 00C (1 in Coating Solution B, it was 100C. Using a heat block on the obtained heat-sensitive recording material, the glass transition temperature was 1000C, (low temperature) and /300C.
When heated at C (high temperature) for 7 seconds, a black image appeared at low temperature,
A red image was obtained at high temperatures. After that, Ricopisino ξ
- A red image was fixed by exposing the entire surface using a Dry 100 model (Ricoh model).

Example 2) Coating liquid B was prepared by adding the dispersion liquid CZO to the coating liquid B of Example 1.
'. Coating solution B' and coating solution A were coated on smooth high-quality paper (toy/m2) by dry weight.
The n2 coating solution A was coated in layers in the order of B' and A at a coating density of 4 zy/m2, and each layer was dried for 0.degree. C.JO minutes to obtain a heat-sensitive recording material.

In coating liquid A, the glass transition temperature of the capsule is 900C.

For coating liquid B, it was 100C.

Using a heat block, the obtained heat-sensitive recording material was heated to 1000
When heated for 7 seconds at 1300C (low temperature) and 1300C (high temperature), a black image was obtained at low temperature, and a red image was obtained at high temperature.

After that, Ricopy Super Dry IOO type (manufactured by Ricoh ■)
The red image was fixed by exposing the entire surface using a .

Example 3 Basic colorless dye precursor of Example 1≠, and xylylene diisocyanate and trimethylol pronotane (j
: / ) Adduct / 1 part ocyphenylethane 2
It was added to a mixed solvent of 1 part of ethyl acetate and 1 part of ethyl acetate to dissolve it.

A solution of this basic colorless dye precursor was mixed with 3.1 parts of polyvinyl alcohol and 1 part of gelatin. The mixture was mixed with an aqueous solution in which F part/4C-di(hydroxyethoxy)benzene 2 and part part were dissolved in water sr part, and emulsified and dispersed at 200C to obtain an emulsion having an average particle size of 3 microns. 100 parts of water was added to the obtained emulsion, and heated to 0°C while stirring, and after 2 hours, a capsule liquid A' containing a basic colorless dye precursor in the core substance was obtained. Part of this capsule liquid A', dispersion liquid A1 of Example 1
To 1 part, lj parts of polyvinyl alcohol were added to prepare a coating liquid A'. This coating solution A' and the coating solution B%C of Example 1
As in Example 1, B,
Laminated and coated in the order of C and A', each ≠00 (:3
A heat-sensitive recording material was obtained by drying for 0 minutes. In coating solution A', the glass transition temperature of the capsule is yo 0c, and in coating solution B, /
It was 200C.

Using a heat block on the obtained heat-sensitive recording material, tooo
When heated for 1 second at c (low temperature) and /100 c (high temperature), a black image was obtained at low temperature, and a red image was obtained at high temperature.

Thereafter, the entire surface was exposed to light using Ricop Sue R-Dry 100 model (manufactured by Ricoh ■) to fix a red image.

[Comparative example]

The basic colorless dye precursor λ and φ parts of Example 1! In addition to 100 parts of polyvinyl alcohol aqueous solution,
After dispersing for μ time, a dispersion E having an average particle size of 3 μ was obtained. 825 parts of this dispersion, Ait part of the dispersion of Example 1, dispersion])
/j part was added to prepare a coating liquid. Next, add phenolphthalein, v part, 100% polyvinyl alcohol aqueous solution.
24 in addition to the sand mill! Time-dispersed average particle size 3
A dispersion E of μ was obtained. This dispersion liquid E was designated as a coating liquid E.

These coating liquids, coating liquid E, and coating liquid C of Example 1
A heat-sensitive recording material was obtained by sequentially coating EXCXD in the order of EXCXD to a dry weight of 4A/rn2 on smooth high-quality paper (Czoy/m2) and drying for ≠00CJO minutes. When the resulting heat-sensitive recording material was heated for 1 second at 1000° C. (low temperature) and 730° C. (high temperature) using a heat block, a black image was obtained at low temperature, and a red image was obtained at high temperature.

Thermal recording material obtained as described above (Example 1.2
．． 3 Comparative Example 1) was thermally recorded using a GI mode thermal printer (Panafax 72oo).

In addition, in order to check the raw storage property, Hiro 0°C × Rio 4R, H,
Similar thermal printing was performed on those subjected to a forced aging test of /day. In order to examine the resistance when contacting the diazo paper after copying, an increase in fog in the background area was examined after contacting the diazo paper immediately after copying for 3 hours.

In order to examine light resistance, after exposure to sunlight for t hours, the decolorization of the printed area and the increase in fog and fog in the background area were examined. To examine solvent resistance, Cemedine was applied to the surface and then the presence or absence of turnip was examined. In order to examine the scratch resistance, the surface was scratched with a fingernail and the presence or absence of color development was examined. The results are shown in Table 1.

"Effects of the Invention" As can be seen from Table 1 below, the recording material of the present invention (Example 1.2.3) has low fogging, high color density, good storage stability, and good resistance to fogging on contact with diazo paper. The increase is also small.

There is no fading of the printed part due to sunlight, and there is almost no background fogging. There is no fog caused by Cemedine painting. Even if I scratch it with my fingernail, there is almost no color.

Patent applicant Fuji Photo Film Co., Ltd. Commissioner of the Patent Office
ni c -6・nil (:l tP 722,
Title of the invention Multi-color thermosensitive recording material 3, Relationship to the case of the person making the amendment Patent applicant Location 210 Nakanuma, Minamiashigara City, Kanagawa Prefecture Name (520) Fuji Photo Film Co., Ltd. Representative Minoru Ohnishi 7゜Contact information 2-26-30-4, Nishiazabu 2-chome, Yuku-ku, Tokyo 106, subject of amendment: “Claims” column of the specification;
The statement in Column 5 of the "Detailed Description of the Invention" and the "Claims" section of the Description of Contents of the Amendment is amended as shown in the attached sheet.

The statement in the "Detailed Description of the Invention" section of the specification is amended as follows.

/) Page 1, line 2Q “Recording materials” "Thermal recording material" and correct it.

λ) Page 2 IO line "Multicolor type color development" "Multicolor type" and correct it.

3) Page 3, line j "Multicolor development" "Multicolor type" and correct it.

4 Rihiro page 10th line "Multicolor type" "Multicolor type" and correct it.

rig page, row 1 "Multicolor type" "Multicolor type" and correct it.

6) Hiroshi page line 73 "Multicolor type" "Multicolor type" and correct it.

7) Page j, line 2 "Multicolor coloring agent type" "Multicolor type" and correct it.

ri page 63 line 12 "Dispersion E was obtained. This dispersion E" "Dispersion F was obtained. This dispersion F" and correct it.

Attached Patent Claims Microcapsules containing a colorless or light-colored basic dye precursor in the core and a color developer that causes a color-forming reaction with the basic dye precursor, or a core containing a colorless or light-colored acidic dye precursor microcapsules containing a diazo compound in the core, a coupling agent that causes a color reaction with the diazo compound, and a color developer that causes a color reaction with the acidic dye precursor; A color erasing agent for a dye produced by a color reaction between a basic dye and a color developer that causes a color reaction, or a color produced by a color reaction between the acidic dye precursor and a color developer that causes a color reaction. 1. A multicolor heat-sensitive recording material, characterized in that it has on the same side of a support.

Claims (1)

[Claims] Microcapsules containing a colorless or light-colored basic dye precursor in the core and a color developer that causes a color-forming reaction with the basic dye precursor, or microcapsules containing a colorless or light-colored acidic dye precursor in the core and the color developer. A color developer that causes a color-forming reaction with an acidic dye precursor, a microcapsule containing a diazo compound in its core, a coupling agent that causes a color-forming reaction with the diazo compound, and a color-forming agent that causes a color-forming reaction with the basic dye precursor and the basic dye. A decoloring agent for a dye produced by a coloring reaction with a color developer that causes a reaction, or a coloring agent produced by a coloring reaction between the acidic dye precursor and a color developer that causes a coloring reaction, is attached to the same support. A multicolor color former type heat-sensitive recording material characterized by having a color former on the surface side.