JPS6340678B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a dye microcapsule liquid for recording materials that prevents coloring. Specifically, the present invention relates to a microcapsule liquid of a hydrophobic solvent solution of an electron-donating dye that prevents coloring and is used as a recording material such as pressure-sensitive copying paper. Pressure-sensitive copying paper is a copying paper that does not use carbon paper (carbonless paper), and with the trend of streamlining office work and the spread of computers, the production volume of pressure-sensitive copying paper has increased significantly in recent years, and demand for this paper is expected to further increase in the future. In the first place, pressure-sensitive copying paper was commercialized by the completion of microencapsulation technology for electron-donating dye solutions, inspired by the color reaction between crystal violet lactone (hereinafter abbreviated as CVL) and acid clay. The performance of pressure-sensitive copying paper has steadily improved due to subsequent technical improvements in dyes, color developers, dye solvents, microcapsules, coating technology, etc. In addition to the acidic clays that have been used since the beginning, as electron-accepting color developers, acidic substances such as phenol-formaldehyde polymers, metal modified phenol-formaldehyde polymers, substituted salicylic acids, or their polyvalent metal salts are used. It has been proposed and put into practical use. Examples of electron-donating dyes include (1) various phthalide dyes represented by CVL, (2) various fluoran dyes, (3) various azaphthalide dyes, and (4) acylleucophenothiazine dyes. , (5) phthalane dye,
(6) diphenylmethane-based dyes, (7) triphenylmethane-based dyes, etc., were proposed in large numbers, and along with the development of color developers, CVL, benzoylleucomethylene blue (BLMB), which has been used since the beginning, and acylleucophenotiazine-based dyes. ), various phthalide dyes and fluoran dyes were put into practical use, and pressure-sensitive copying paper that produced various hues such as red, green, black, and yellow in addition to blue was put into practical use. After these dyes are dissolved in a hydrophobic solvent, they can be encapsulated using various microencapsulation methods. It has been microencapsulated by a microcapsule method using a synthetic resin film (for example, a urea formaldehyde resin film, a melamine formaldehyde resin film, a polyamide resin film, etc.) and has been put to practical use in pressure-sensitive copying paper. However, pressure-sensitive copying paper that combines the above-mentioned acidic color developer and various dyes quickly develops deep colors when written on, typewriter pressure, etc., but the storage fastness of the colored image (light fastness) , heat resistance, solvent resistance, etc.), and the color image disappears when exposed to light, comes into contact with polar solvents such as plasticizers, or is stored at high temperatures, making it unreadable. However, there was a strong desire for improvement. As a technique for improving the fastness of colored images on pressure-sensitive copying paper, the use of methine dyes, represented by triphenylmethane dyes, has been proposed (Japanese Patent Publication No. 1973-
16052, Japanese Unexamined Patent Publication No. 50-20808). Pressure-sensitive copying paper using methine dyes such as these triphenylmethane dyes and acidic color developers (e.g., clay color developers such as acid clay, phenol condensate color developers, etc.) It develops extremely deep colors, and its color images are characterized by significantly superior fastness compared to phthalide dyes such as CVL, and color images produced using fluoran dyes and acidic color developers. be. However, these methine dyes are (a) unstable upon storage and often colored by photochemical reactions, and (b) because they are applied to pressure-sensitive copying paper.
After dissolving these dyes in a hydrophobic solvent, they can be made into microcapsules by various methods such as gelatin-gum arabic complex coacervation encapsulation or in-situ polymerization polyurea membrane encapsulation. Many of them are colored, and furthermore, (c) the pressure-sensitive copying paper coated with the microcapsule liquid is also colored, giving an impression different from that of ordinary paper, which has made it difficult to put it into practical use. As a result of intensive study based on the above-mentioned problems, the inventors have developed the general formula () (In the formula, X, Y, and Z are a phenyl group that may have a substituent, a naphthyl group that may have a substituent, a β-styryl group that may have a substituent, or an aromatic group that may have a substituent. A methine dye represented by a heterocyclic ring residue, which may be the same or different, and two of X, Y, and Z may be bonded to form a ring. After dissolving in a hydrophobic solvent, by coacervation method, interfacial polymerization method or I-situ polymerization method,
In the process of forming microcapsules of minute oil droplets coated on a natural or synthetic polymer membrane wall, it is possible to obtain a dye microcapsule liquid with extremely little coloring by adding a sequestering agent, and to apply the microcapsules. The present invention was completed based on the discovery that the pressure-sensitive copying paper obtained also has very little coloring, shows no tendency to color during storage, and has little tendency to color when exposed to light. The recording material dye used in the microcapsule liquid of the present invention has the general formula () (In the formula, X, Y, and Z are a phenyl group that may have a substituent, a naphthyl group that may have a substituent, a β-styryl group that may have a substituent, or an aromatic group that may have a substituent. A colorless or light-colored compound representing a group of heterocyclic ring residues, which may be the same or different, and two of X, Y, and Z may be combined to form a ring. It is a pigment. X in a compound of general formula (),
The aromatic heteroaromatic ring represented by Y and Z is as follows:

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Typical examples include [Formula], but the invention is not limited to these. Substituents that can be bonded to carbon atoms or heteroatoms of benzene rings, naphthalene rings, β-styryl groups, or aromatic heterocyclic residues include halogen atoms, lower alkyl groups, lower halogenated alkyl groups, and cycloalkyl groups. group, lower alkoxy group,
Acyl group, carbalkoxy group, cyanoalkyl group, cyano group, hydroxyl group, nitro group, phenyl group,
benzyl group, substituted phenyl group, substituted benzyl group,
A phenoxy group that may have a substituent, a benzyloxy group that may have a substituent, an amino group, a piperazinyl group that may have a substituent,
Substituents include lower alkyl groups, cycloalkyl groups, cyanoalkyl groups, halogenated alkyl groups,
Substitution having one or two hydroxyalkyl groups, phenyl groups, halo or nitrophenyl groups, benzyl groups, halo or nitrobenzyl groups (the groups bonded to the N-atom may be the same or different) These include an amino group, a polymethylene amino group (eg, a pyrodylino group, a piperidino group), and a morpholino group, and the substituents may be bonded to each other to form a ring. Specifically, methine dyes used in the present invention are exemplified by (A) triphenylmethane dyes, such as 4,4',4''-tris-dimethylamino-triphenylmethane, 4,4'-bis -dimethylamino-
4″-methylamino-triphenylmethane, 4,
4'-bis-methylamino-4''-dimethylaminotriphenylmethane, 4,4',4''-tris-amino-triphenylmethane, 4,4',4''-tris-diethylamino-triphenylmethane, 4 , 4'-bisdiethylamino-4''-ethylamino-triphenylmethane, 4,4'-bisdiethylamino-4''-
Amino-triphenylmethane, 4,4'-bis-dimethylamino-triphenylmethane, 4-dimethylamino-triphenylmethane, 4,4'-bis-
Dimethylamino-2″-chloro-triphenylmethane, 4,4′-bis(N-benzyl-N-methylamino)triphenylmethane, 4,4′-bisdiisopropylamino-3″-bromotriphenylmethane, 4 , 4'-bisdiethylamino-triphenylmethane, 4,4'-bisdimethylamino-4''-methoxytriphenylmethane, 4,4'-bisdimethylamino-4''-ethoxytriphenylmethane, 4,
4'-bisdimethylamino-3''-methyl-4''-methoxytriphenylmethane, 4,4'-bisdimethylamino-3''-methyl-4''-ethoxytriphenylmethane, 4,4'-bisdimethylamino −3″, 4″−
Dimethoxytriphenylmethane, 4,4'-bisdimethylamino-2'',4''-dimethoxytriphenylmethane, 4,4'-bis-diethylamino-3''-ethyl-4''-ethoxy-triphenylmethane, 4,
4'-bis-methylamino-3,3-dimethyl-
3″-butyl-4″-butoxy-triphenylmethane, 4,4′-bis-dimethylamino-3″-cyclohexyl-4″-methoxy-triphenylmethane,
4,4′-bis-propylamino-3″-phenyl-
4'-propoxy-triphenylmethane, 4,4'-
Bis(N-benzyl-N-methylamino)-3″-
Propyl-4″-methoxytriphenylmethane,
4,4′-bis-N-pyrrolidino-3″-methyl-
4″-Methoxy-triphenylmethane, 4,4′-bis-N-piperidino-3″-butyl-4″-ethoxy-triphenylmethane, 4,4′-bis-N-piperidino-3″,4″ -dimethoxy-triphenylmethane, 3,3'-dimethyl-4,4'-bismethylamino-3'',4''-dimethoxytriphenylmethane,
4,4',4''-trisamino-3-methyl-triphenylmethane, 4,4',4''-trisamino-3,
3′,3″-trimethyl-triphenylmethane, 4,
4',4''-trisethylamino-3,3'-diethyl-triphenylmethane, 3,3'-dimethyl-4,
4'-bisethylamino-4''-dimethylamino-triphenylmethane, 4,4'-bisdimethylamino-3''-methyl-4''-amino-triphenylmethane, 4,4'-bisdimethylamino-3 ″-methyl-
4″-methylamino-triphenylmethane, 4,
4'-bis(N-P-chlorobenzyl-N-methylamino)-4''-dimethylamino-triphenylmethane, 4,4',4''-trisphenylamino-triphenylmethane, 4,4', 4″-tris(N-methyl-N-phenyl-amino)triphenylmethane, 4,4′-bismorpholino-4″-dimethylaminotriphenylmethane, 4,4′-bis(N-cyclohexyl-N-methyl amino)-4″-dipropylaminotriphenylmethane, 4,4′,4″-tris-dipropylamino-2,2′-dimethyl-triphenylmethane, 4,4′,4″-tris-dimethylamino -3,3'-dimethyl-triphenylmethane, 4,4',4''-tris-dimethylamino-2-
Methyl-triphenylmethane, 4,4',4''-tris-dimethylamino-2-methoxy-triphenylmethane, 4,4',4''-tris-diethylamino-3-methyl-triphenylmethane, 4,4 '-Bis-dimethylamino-4''-N-benzylamino-
Triphenylmethane, 4,4'-bis-dimethylamino-4''-N-benzylamino-2''-methoxytriphenylmethane, 4,4'-bis-dimethylamino-4''-N-benzylamino-3'' -Methyltriphenylmethane, 4,4'-bis-dimethylamino-
3″-chloro-4″-N-benzylaminotriphenylmethane, 4,4′-bis-dimethylamino-4″-
(N-benzyl-N-methylamino)triphenylmethane, 4,4'-bis-dimethylamino-4''-
(N-orthochlorobenzyl-N-methylamino)
Triphenylmethane, 4,4'-bis-dimethylamino-4''-(N-parachlorobenzyl-N-methylamino)triphenylmethane, 4,4'-bis-
Dimethylamino-4″-(N-paramethylbenzyl-N-methyl)triphenylmethane, 4,4′-bis-dimethylamino-4″-(N,N-dibenzylamino)triphenylmethane, 4,4 '-Bis-dimethylamino-4''-(N-phenyl-N-methylamino)triphenylmethane, 4,4'-bis-dimethylamino-4''-morpholino-triphenylmethane, 4,4'-bis- N-benzylamino-4″-
Dimethylamino-triphenylmethane, 4,4'-
Bis-(N-benzyl-N-methylamino)-4″-dimethylaminotriphenylmethane, 4,4′-bis-(N-parachlorobenzyl-N-methylamino)
-4″-dimethylamino-triphenylmethane,
4,4'-bis-(N-parabromobenzyl-N-
ethylamino)-4″-diethylamino-triphenylmethane, 4,4′-bis-(N-orthochlorobenzyl-N-methylamino)-4″-dipropylamino-triphenylmethane, 3,3′-dichloro -4,4'-bis-(N-benzylamino)-4''-dimethylamino-triphenylmethane, 4,4'-bis-(N-p-methylbenzyl-N-methylamino)-4''-dimethyl amino-triphenylmethane,
4,4'-bis-(N-p-methylbenzyl-N-
ethylamino)-4″-diisopropylamino-triphenylmethane, 3,3′-dimethyl-4,4′-
Bis-(p-methylbenzylamino)-4″-dimethylaminotriphenylmethane, 3,3′-dimethyl-4,4′-bis-(N-benzylamino)-4″-dimethylamino-triphenylmethane, 3,3'-dibutyl-4,4'-bis-(N-benzylamino)-
4″-diethylamino-triphenylmethane, 2,
2'-dimethyl-4,4'-bis-(N-benzylamino)-5,5'-dimethyl-4''-dimethylamino-triphenylmethane, 2,2'-dimethyl-4,
4'-bis(N-benzyl-N-ethylamino)-
4″-dimethylamino-triphenylmethane, 4,
4'-bis-(N-benzyl-N-ethylamino)-
Triphenylmethane, 4,4'-bis(diethylamino)-2'-chlorotriphenylmethane, 3,
3'-dimethyl-4,4'-bis-(N-ethyl-N
-β-hydroxyethylamino)-4″-diethylaminotriphenylmethane, 4,4′-bis-(N
-methyl-N-β-hydroxyethyl)-2″-chloro-triphenylmethane, 4,4′-bis-(N
-ethyl-N-β-hydroxyethyl)-2″-methyl-triphenylmethane, 4,4′-bis-(N
-Methyl-N-β-hydroxyethyl)-2″-methyl-4″-diethyltriphenylmethane, 4,
4′-bis-(N-methyl-N-β-hydroxyethyl)-2″-methyl-4″-dimethylaminotriphenylmethane, 4,4′-bis-(N-propyl-
N-β-hydroxyethyl)-2″-bromo-4″-
Dipropylaminotriphenylmethane, 4,4'-
Bis-dimethylamino-2″-methyl-5″-methoxy-triphenylmethane, 4,4′-bis-dimethylamino-2″,5″-dimethyl-triphenylmethane, 4,4′-bis-diethylamino- 4″-Methyl-triphenylmethane, 4,4′-bis-dimethylamino-3″-methyltriphenylmethane, 4,
4′-bis-dimethylamino-3″,4″-methylenedioxytriphenylmethane, 4,4′-bis(N-
p-chlorobenzyl-N-methylamino)-3″,
4″-methylenedioxytriphenylmethane, 4,
4'-bis-N-pyrrolidino-4''-dimethylamino-triphenylmethane, 4,4'-bis-N-pyrrolidino-4''-N-methyl-N-benzylamino-
Triphenylmethane, 4,4′-dimethoxy-4″-
Pyrrolidinotriphenylmethane, 4,4'-diethoxy-4''-piperidino-triphenylmethane, (B)
Indolylmethine dyes, such as phenyl-bis-(1-ethyl-2-methyl-indole-3-
yl)methane, 4-methoxyphenyl-bis-
(1'-ethyl-2'-methylindol-3'-yl)
Methane, 3-methyl-4-methoxyphenyl-bis-(1'-ethyl-2'-methylindol-3'-yl)methane, 3,4-dimethoxyphenyl-bis-(1'-ethyl-2 '-Methylindol-3'-yl)methane, 2,4-dimethoxyphenyl-bis-(1'-ethyl-2-methylindol-3'-yl)methane, 3,4-diethoxyphenyl-bis -(1'-ethyl-2'-methylindol-3'-yl)methane, 3-butyl-4-methoxyphenyl-bis-(1'-butyl-2'-methylindole-
3'-yl)methane, 4-ethoxyphenyl-bis-(1'-ethyl-2'-phenylindol-3'-yl)methane, 4-ethoxyphenyl-bis-
(1'-ethyl-2'-methyl-indol-3'-yl)methane, phenyl-bis-(1'-n-butyl-2'-methyl-indol-3'-yl)methane,
Phenyl-bis-(1'-methyl-2'-phenylindol-3'-yl)methane, bis-(4-dimethylaminophenyl)-(1'-ethyl-2'-methyl-indole-3' -yl)methane, bis-(1-
ethyl-2-methyl-indol-3-yl)-
2'-naphthyl-methane, bis-(1-ethyl-2
-Methyl-indol-3-yl)-1'-naphthylmethane, tris-(1-ethyl-2-methyl-
indol-3-yl)methane, tris-(1-
n-butyl-2-methylindol-3-yl)
Methane, bis-(1-ethyl-2-methyl-indol-3-yl)-3'-chloro-4'-methoxyphenylmethane, bis-(1-carboxyethyl-2-methyl-indol-3-yl) )-phenylmethane, bis-(1-propyl-2-phenyl-indol-3-yl)-phenylmethane, bis-(1-octyl-2-methyl-indole-
3-yl)phenylmethane, bis-(1-benzyl-2-methyl-indol-3-yl)phenylmethane, bis-(1-ethyl-2-methyl-indol-3-yl)-2'-methylphenylmethane , bis-(1-ethyl-2-methyl-indol-3-yl)-3'-methylphenylmethane, bis-(1-ethyl-2-methyl-indole-3
-yl)-4'-methylphenylmethane, bis-(1
-ethyl-2-methyl-indol-3-yl)
-2'-methoxyphenylmethane, bis-(1-ethyl-2-methyl-indol-3-yl)-
4'-fluorophenylmethane, bis-(1-ethyl-2-methyl-indol-3-yl)-4'-bromphenylmethane, bis-(1-hexyl-indol-3-yl)-phenylmethane, Bis-
(1-ethyl-2-methyl-indol-3-yl)-3'-nitrophenylmethane, bis-(1-ethyl-2-methyl-indol-3-yl)-3',
4'-Dichlorophenylmethane, bis-(1-ethyl-2-methyl-indol-3-yl)-2'-
thienyl-methane, bis-(1-ethyl-2-methyl-indol-3-yl)-1'-methyl-
2'-thienylmethane, bis-(1-butyl-2-
Methyl-indol-3-yl)-4'-pyridyl-methane, (C) Naphthylmethine dyes, such as bis-(4-dimethylamino-naphthyl-1)-4'-
Dimethylaminophenylmethane, bis-(4-ethylamino-naphthyl-1)-4'-dimethylaminophenylmethane, bis-(4-N-paratolyl-N-methylamino-naphthyl-1)-4'- Isopropylaminophenylmethane, tris-(4-
dimethylamino-naphthyl-1) methane, bis-
(4-dimethylamino-naphthyl-1)-4'-N-
Morpholinophenylmethane, bis-(4-N benzylaminophenyl)-1-naphthyl-methane,
Bis-(4-diethylaminophenyl)-4'-N-
Phenylaminonaphthyl-1-methane, bis-
(4-diethylaminophenyl)-4'-ethylnaphthyl-1-methane, bis-(4-N-phenyl-
N-methylnaphthyl-1)-β-styrylmethane,
Bis-(4-dimethylamino-naphthyl-1)-p
-Chlorstyrylmethane, bis-(4-dimethylaminophenyl)-2'-methoxynaphthyl-1'-
Methane, bis-(4-dimethylaminophenyl)-
4'-Methoxynaphthyl-1'-methane, bis-(4
-dimethylaminophenyl)-naphthyl-2'-methane, bis-(4-N propylphenyl)-4'-propoxynaphthyl-2'-methane, bis-(4-dimethylaminonaphthyl-1)-2' -pyridylmethane, bis-(4-dimethylaminonaphthyl-1)-
2'-pyrazylmethane, bis-(4-dibenzylaminonaphthyl-1)-quinolin-3'-yl-methane, (D) carbazolylmethine dyes, such as bis-
(9-ethyl-carbazol-3-yl)-phenyl-methane, bis-(9-ethyl-carbazol-3-yl)-4'-methoxyphenylmethane, bis-(9-butyl-carbazol-3-yl) )−
4'-dimethylaminophenylmethane, bis-(9
-methyl-carbazol-3-yl)-3'-chlorophenylmethane, bis-(9-benzyl-carbazol-3-yl)-4'-N-phenylaminophenylmethane, bis-(9-octyl -carbazol-3-yl)-4'-cyanoethylamino-
Naphthyl-1'-methane, tris-(9-benzyl-carbazol-3-yl)methane, bis-(9
-ethylcarbazol-3-yl)-2'-furylmethane, bis-(9-methyl-carbazol-3-yl)-2'-furylmethane,
-yl)-2'-thienylmethane, bis-(9-ethylcarbazol-3-yl)-9'-methyl-carbazol-3'-yl-methane, bis-(9-methylcarbazol-3-yl)- β-styrylmethane, bis-(9-propyl-carbazole-3-
yl)-1'-octyl-2'-phenyl-indol-3'-ylmethane, bis-(4-dimethylaminophenyl)-9'-ethylcarbazol-3'-ylmethane, bis-(2-methyl-4 -diethylaminophenyl)-9'-ethylcarbazole-3'-
ylmethane, bis-(4-piperidinophenyl)-
9'-Butylcarbazol-3'-ylmethane, bis-(4-N-cyclohexylaminophenyl)-
9'-Ethylcarbazol-3'-ylmethane, bis-(1-butyl-2-methyl-indole-3-
yl)-9'-ethylcarbazol-3'-ylmethane, bis-(3-diethylamino-6-pyridyl)
-9′-ethylcarbazol-3′-ylmethane, (E)
In the general formula (), a methine dye in which X, Y, and Z combine to form a ring, such as 3,6-bis-dimethylamino-9-phenylxanthene,
3,6-bisdiethylamino-9-(4'-diethylaminophenyl)xanthene, 9-(4'-dibutylaminophenyl)xanthene, 3-diethylamino-6,7-dimethyl-9-phenylxanthene, 3, 6-dimethoxy-9-(4'-dimethylaminophenyl)xanthene, 3,6-bisdiethylamino-9-(4'-methoxyphenyl)xanthene, 3,6-diethoxy-9-(4'-amino- naphthyl-1')xanthene, 3,6-bis-diethylamino-9-(1'-ethyl-2'-methyl-
indol-3'-yl)xanthene, 3,6-bis-dibutylamino-9-(4'-methyl-2'-pyridyl)xanthene, 3-(N-phenyl-N-
methylamino)-6-methoxy-9-(3'-nitro-4'-methylphenyl)xanthene, 3,6-bis-diethylamino-9-(2',4'-dipropoxyphenyl)xanthene, 3,6 -bis-dimethylamino-9-phenylthioxanthene, 3,6
-dimethylamino-9-(4'-chlorophenyl)-
10-methyl-9,10-dihydroacridine, 3,
6-bis-(N-methyl-Nbenzylamino)-9
-(4'-dipropylaminophenyl)-10-methyl-9,10-dihydro-acridine, 3,6-bis-diethylamino-9-(4'-methoxyphenyl)
Fluorene, 3,6-bis-dimethylamino-9
-(4′-dimethylaminophenyl)fluorene,
(F) Other methine dyes such as bis-
(4-dimethylaminophenyl)-β-styryl-
Methane, bis-(3-methyl-4-N-phenylaminophenyl)-β-styrylmethane, bis-
(3-methyl-4-N-methylaminophenyl)-
4'-pyridylmethane, bis-(3-cyclohexyl-4-dimethylaminophenyl)-2'-furyl-methane, bis-(3-methoxy-4-dibenzylaminophenyl)-2'-thienylmethane, Bis-(3-chloro-4-dimethylaminophenyl)-
1'-Ethyl-pyrrol-2-ylmethane, bis-
4-dibutylaminophenyl-quinolin-2'-yl-methane, bis-4-dimethylaminophenyl-1'-ethyl-2'-methyl-5',6'-benzoindol-3'-ylmethane, bis -4-Methylaminophenyl-9'-methylcarbazol-3'-ylmethane, bis-(4-dimethylaminophenyl-
β-(4′-methoxystyryl)-methane, bis-
(4-N-benzylaminophenyl)-β-(3′,
4′-diethoxystyryl)-methane, bis-(4-
N-benzyl-Nethylaminophenyl)-β-
Methine dyes such as (3'-methyl-4'-diethylaminostyryl)methane, bis-(4-N-cyclohexyl-N-ethylphenyl)-β-(4'-butylstyryl)methane, etc. are used, but examples include However, the present invention is not limited to the compounds mentioned above. In addition, one or more types of other dyes such as phthalide dyes, fluoran dyes, azaphthalide dyes, or phenothiazine dyes may be mixed and the coloring prevention effect can be similarly achieved. The sequestering agents used in the microcapsule liquid of the present invention include calcium, magnesium, iron, etc., which are derived from water and are present in the aqueous medium used when manufacturing microcapsules by various microencapsulation methods. When used as pressure-sensitive copying paper by applying polyvalent metal ions and microcapsules, sizing agents and fillers (clay, titanium oxide, calcium carbonate, magnesium carbonate, etc.) used in the production of pressure-sensitive copying base paper ), etc., and combine with polyvalent metal ions such as aluminum, calcium, magnesium, titanium, and iron present in the microcapsule layer of pressure-sensitive copying paper to form stable chelate compounds, and when microencapsulated, methyl-based Any dye may be used as long as it prevents undesirable coloring caused by the presence of polyvalent metal ions. Such sequestering agents include ethylenediaminetetraacetic acid, N-hydroxyethylethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraaminehexaacetic acid, nitrilotriacetic acid, N-hydroxyiminodiacetic acid, diethanolglycine, iminodiacetic acid, glycol Ether diamine tetraacetic acid, 1,3-
Organic water-soluble sequestering agents such as diaminopropan-2-ol tetraacetic acid, tartaric acid, gluconic acid, citric acid, sugar acids or their alkali metal salts, metal salts of digninsulfonic acid, N,N'-disalicilyl Schiff bases such as denethylenediamine, 1,3-diketones such as trifluoroacetylacetone, thenoyltrifluoroacetone, and pivaloyltrifluoroacetone, organic ion sequestrants soluble in dye solvents such as higher amide derivatives of ethylenediaminetetraacetic acid; Examples include, but are not limited to, polymerized phosphates such as sodium tripolyphosphate, sodium polymetaphosphate, sodium pyrophosphate, and sodium dihydrogen pyrophosphate. For some of these metal ion sequestering agents, the chelate stability constant with polyvalent metal ions changes significantly depending on the pH value of the system, so when microencapsulating,
One or more appropriate metal ion sequestering agents are selected and used depending on the pH of the coated paper for the support such as paper and during storage of the microcapsules. The amount of these metal ion sequestering agents used is preferably 0.1 to 100 parts by weight per 100 parts of the methine dye, and usually, a sufficient coloring prevention effect can be achieved by using 100 parts by weight or less. In the coacervation microcapsule production process, use of an excessive amount of sequestering agent may inhibit the formation of microcapsules. Furthermore, it is effective to coexist an ultraviolet absorber as an additive in the microcapsule liquid to prevent coloring of the pressure-sensitive copying paper obtained by coating the microcapsules upon exposure to light. As a UV absorber, (1) General formula () (In the formula, R ₁ , R ₂ , and R ₃ each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an aralkyl group.) For example, a benzotriazole compound represented by 2-(2'-hydroxy-5' -methylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2
-(2'-hydroxy-3',5'-di-tertiary-butylphenyl)-5-chlorobenzotriazole,
2-(2'-Hydroxy-3',5'-Dietary-
amyl phenyl) benzotriazole, 2-
(2′-hydroxy-5′-octoxyphenylbenzazole, etc., (2) General formula () (In the formula, R ₁ , R ₂ , and R ₃ each represent a hydrogen atom, a hydroxyl group, an arylalkoxy group, an alkoxy group, a sulfonic acid group, or an aryl group bonded with an alkylene or sulfur atom.) , for example, 2,4-dihydroxybenzophenone, 2-hydroxy-4
-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,
2',4,4'-tetrahydroxybenzophenone,
2-Hydroxy-4-octoxy-benzophenone, 2,2'-dihydroxybenzophenone, 2,
2'-dihydroxy-4'-methoxy-benzophenone, 2-hydroxy-4-methoxy-benzophenone-5-sulfonic acid, 2,2'-dihydroxy-
4,4'-dimethoxybenzophenone, benzophenone-5-sulfonic acid, etc. (3) General formula (), (In the formula, R ₁ , R ₂ , R ₃ are hydrogen atoms, alkyl groups,
(4) general formula (), such as phenyl salicylate, p-tert-octyl phenyl salicylate, p-tert-butylphenyl salicylate, etc. Substituted acrylonitrile derivatives represented by (wherein R represents an alkyl group, an aryl group, or an aralkyl group), such as ethyl 2-cyano-3,3-diphenyl acrylate, 2-cyano-3,3-diphenyl acrylate, 2-ethylhexyl enyl acrylate, etc. (5)
General formula () or (), (In the formula, R ₁ , R ₂ , and R ₃ represent an alkyl group, an aryl group, or a heterocyclic residue, and R ₁ and R ₂ together with the carbon atoms to which they are bonded represent a saturated alicyclic ring or an alkylpiperidine ring. , X represents an oxygen radical or a lower alkyl group, and n is an integer from 1 to 3), for example,
4-benzoyloxy-2,2,6,6-tetramethylpiperidine and the like are useful. Many of these ultraviolet absorbers are oil-soluble and are used by being dissolved in a hydrophobic solvent together with the dye. The water-soluble UV absorber may be added to the water layer before microencapsulation or after microencapsulation. The amount of these ultraviolet absorbers to be used is preferably 0.1 to 100 parts by weight per 100 parts of the methine dye, and the use of 100 parts by weight or less can usually sufficiently achieve the effect of preventing coloring due to light. To produce the microcapsule liquid of the present invention,
For example, there is a coacervation method, an interfacial polymerization method, or an in-situ polymerization method. Specifically, [A] Coacervation: (1) Coacervate on the surface of the dye solution due to electrical interaction between polycation colloid and polyanionic colloid, such as coacervation of gelatin and gum arabic. Complex coacervation method that utilizes membrane formation; (2) Salt coacervation method that utilizes the salting out effect produced by adding an electrolyte to an aqueous solution of a hydrophilic polymer such as gelatin; (3) Gelatin, etc. A simple coacervation method that utilizes a coacervate film formed by adding a non-solvent (non-electrolyte such as alcohol) for a hydrophilic polymer; (4) A method that insolubilizes and precipitates a polymer by changing the pH of an aqueous polymer solution. , [B] A variety of different polymeric materials are contained in both the dispersion medium (water) and the core substance (dye solution) dispersed therein, and polymerization or condensation is performed at the interface between the two to form microcapsules of synthetic resin film. For example, a polyamide membrane microcapsule liquid, an unsaturated polyester membrane microcapsule liquid, a polyurea urethane membrane microcapsule liquid, which is formed at the interface between a dye solution in which terephthalic acid chloride is dissolved and an aqueous solution of a polyvalent amine, Epoxy membrane microcapsule liquid, silicone membrane microcapsule liquid, unsaturated dicarboxylic acid styrene polymer microcapsule liquid, etc. [C] In-situ polymerization method allows film formation from only the inside or outside of the core material (dye solution). In this method, the material is supplied and conditions are set so that the reaction occurs on the surface of the dye solution, and the resulting polymer is used as the wall membrane of the microcapsule. As the material, not only monomers but also low polymers and initial condensates can be used. Specifically, (1) a polyurethane capsule solution in which a polyvalent isocyanate and a polyhydroxy compound are dissolved in a dye solution, and this is emulsified in water and reacted by raising the temperature; (2) a polyurethane capsule solution in which a polyvalent isocyanate and a polyhydroxy compound are dissolved in a dye solution; In the presence of an anionic polyelectrolyte dissolved in water, the PH
Polyurea that forms a urea-formaldehyde resin film on the surface of the dye solution by adjusting and increasing the temperature, or forms a urea-formaldehyde resin film on the surface of the dye solution by adjusting the pH using a water-soluble urea-formaldehyde prepolymer. (urea resin) capsule liquid, (3) polystyrene membrane microcapsule liquid using other film-forming materials, melamine membrane microcapsule liquid, melamine-polyurea membrane microcapsule liquid, microcapsule liquid with formalized polyvinyl alcohol membrane, etc. It will be done. Although there are various methods as described above, the method is not limited to these methods, and various microencapsulation methods can be applied to exhibit the coloring prevention effect. In these methods, various hydrophobic high boiling point solvents can be used as the solvent for the methine dye represented by the general formula (), such as methylnaphthalene, diisopropylnaphthalene, methylpropylnaphthalene, di-tert-butyl Alkylnaphthalenes such as naphthalene, diarylalkanes such as diphenylethane, phenylxylylethane, dixylylmethane, diphenylpropane, and phenylxylylpropane, alkylbiphenyls such as isopropylbiphenyl and diethylbiphenyl, hydrogenated terphenyl, triaryldimethanes such as triphenyldimethane,
Non-polar hydrophobic solvents such as alkylindanes, alkylbenzenes, benzylnaphthalenes, diallylalkylenes, dibutyl phthalate, dioctyl phthalate, di-dodecyl phthalate, dioctyl adipate, tri-2-ethylhexyl trimellitate, dioctyl sebacate, dibutyl aze One type of polar hydrophobic solvent such as aromatic or aliphatic carboxylic acid esters such as benzyl benzoate, alkyl diphenyl ethers, alkyl benzophenones, and phosphoric acid esters (tricresyl phosphate, etc.) or a mixture of two or more types, which is liquid when microencapsulated;
and high boiling point organic solvents. The microcapsule liquid of the present invention can be applied to pressure-sensitive copying paper, for example, as follows. This microcapsule liquid is mixed into cellulose powder (pulp powder), starch particles (wheat, corn,
Products manufactured from raw materials such as potatoes, sweet potatoes, sago, tapiota, rice, glutinous rice, and glutinous corn, oxidized starches obtained by reacting these with oxidizing agents, esterified starches such as acetylated starches, and etherified starches. starch, starch derivatives such as aldehyde starch, modified starch), stilts for pollution prevention such as talc, clay, calcium carbonate, polystyrene resin, and water-soluble polymers as adhesives (polyvinyl alcohol, soluble starches, carboxymethyl cellulose, After mixing with an aqueous solution (such as casein) to form an aqueous coating solution, it is applied onto a support such as paper to obtain a pressure-sensitive copying paper. Furthermore, the microcapsule liquid of the present invention can also be applied to pressure-sensitive copying paper, which is coated on the same side of a color developer and a substrate to develop color on a single sheet. Furthermore, in addition to pressure-sensitive copying paper, it can also be applied to thermal recording paper that uses microcapsules, and recording materials in which microcapsules are destroyed by heat generated by an electric current and reacted with a color developer to form a colored image. It is. The microcapsule liquid of the present invention, that is, the metal is added to the microcapsules of a hydrophobic solvent solution containing a methine dye by various microencapsulation methods such as coacervation method, interfacial polymerization method, and in-situ polymerization method. A microcapsule liquid obtained using an ion sequestering agent, more preferably a UV absorber, exhibits the following extremely excellent effects. (1) There is very little coloring of the microcapsule liquid. (2) When this microcapsule liquid is applied to pressure-sensitive copying paper, there is very little coloration on the surface coated with the microcapsules, and there is no noticeable difference visually from ordinary high-quality paper under storage conditions under light exposure. It becomes possible to significantly suppress undesirable scumming on the coated surface (which is thought to be caused by color development due to photooxidation of the coated surface). These extremely excellent effects have made it possible to apply methine dyes, which have hitherto been extremely unstable in the environment and could not be put to practical use, into pressure-sensitive copying paper and other recording materials. That is, for example, a pressure-sensitive copying paper using the microcapsule liquid of the present invention has extremely little coloring, has excellent storage stability, and has excellent fastness to light and plasticizer of a colored image. Ru. Hereinafter, the present invention will be specifically explained with reference to Examples. In addition, parts in the examples mean parts by weight. Example 1 Ryuko Crystal Violet (4,4',
4″-trisdimethylaminotriphenylmethane)
diisopropylnaphthalene dissolved in 4% by weight of
12.6 parts of gelatin and 6% acid-treated gelatin aqueous solution containing 0.2 parts of ethylenediaminetetraacetic acid disodium salt were mixed and emulsified by stirring at 55°C using a homomixer. 160, degree of etherification 0.70) was mixed with 50 parts of a 1% aqueous solution of
Add 30 parts to dilute, adjust the pH to 4.3 with acetic acid,
Causes coacervation. Subsequently, while stirring is continued, the liquid temperature is cooled to 8 to 9°C to gel the coacervate film. Furthermore, 37% formalin
After adding 1.75 parts, 10% caustic soda aqueous solution was gradually added dropwise to adjust the pH to 10.5, harden the coacervate film, further raise the liquid temperature to 40°C, and then let it cool to room temperature to complete microencapsulation. do. Add 20 parts of cellulose powder and 25 parts of a 20% aqueous solution of oxidized starch to 100 parts of this microcapsule liquid (dry weight), stir and mix thoroughly, and then coat on high-quality paper so that the dry coating amount is 4.0 g/ ^m2 . The mixture was applied and dried using a bar coater to prepare pressure-sensitive copying paper. Almost no coloring was observed in the microcapsule liquid and the pressure-sensitive copying paper, and the reflection density value (hereinafter simply referred to as reflection density value) measured by a Macbeth densitometer of the microcapsule-coated surface of the upper paper was 0.07. When no sequestering agent was used, the microcapsules were colored blue and the reflection density value of the top paper was
It was 0.30. Example 2 Dioctyl phthalate (DOP) in which 5% by weight of 4,4′-bis-dimethylamino-4″-N-benzyl-N-methylamino-triphenylmethane was dissolved.
100 parts, 0.4 parts of N-hydroxyethyl-ethylenediaminetriacetic acid disodium salt, 20 parts of acid-treated gelatin dissolved in 160 parts of water, and the pH adjusted to 10.0 with 10% caustic soda aqueous solution were mixed and emulsified with a homomixer. Next, 20 parts of gum arabic and 0.3 parts of sodium salt of polymethyl vinyl ether maleic anhydride dissolved in 150 parts of water at 55°C were added, followed by high-speed emulsification for an additional 30 minutes. Next, 200 parts of warm water at 55°C was added dropwise over 30 minutes, and then the pH was lowered to 4.5 with a 10% acetic acid aqueous solution to cause coacervation. Next, the temperature of the system was cooled to 7℃, 21 parts of 37% formalin was added, and the pH of the system was raised to 10.5 over 30 minutes with a 10% NaOH aqueous solution, and then slowly raised to 50℃. The microcapsule membrane was heated to complete curing and microencapsulation was completed. 100 parts of this microcapsule liquid, 5 parts of wheat starch granules (average particle size 25μ), and 20% of oxidized starch
4 parts of an aqueous solution were thoroughly mixed and coated in the same manner as in Example 1 to prepare pressure-sensitive copying paper. The microcapsule liquid was white, and the upper paper coated with the microcapsule liquid was also white, with a reflection density value of 0.06 on the coated surface. When no sequestering agent was used, the microcapsule liquid was colored blue and the reflection density value of the top paper was 0.28. Examples 3-12 4,4′-bisdimethylaminophenyl-4″-
Instead of (N-benzyl-N-methylamino)-triphenylmethane, 4,4'-dimethoxy-4''-dimethylamino-triphenylmethane, 4,4'-dimethylamino-3'',4''-dimethoxy -triphenylmethane, 4,4'-dimorpholino-4''-dimethylamino-triphenylmethane, bis(1-ethyl-2-methyl-indol-3-yl)-3',
4'-dimethoxyphenylmethane, bis(1-ethyl-2-methylindol-3-yl)-2'-naphthylmethane, bis(4-dimethylaminophenyl-4'-methoxynaphthyl-1'-methane, Bis(4'-dimethylaminophenyl)-9'-ethylcarbazol-3'-ylmethane, bis(4'-dimethylaminophenyl)-2'-pyridyl-methane, 3,
3′,3″-trimethyl-4,4′,4″-triamino-
Microcapsule liquefaction and pressure-sensitive copying paper were prepared using triphenylmethane and 3,6-bisdiethylaminophenyl-9-phenylxanthene in the same manner as in Example 2. The results are shown in Table-1.

【table】

[Table] Example 13 Ryuko Crystal Violet (4,4',
4″-tris-dimethylamino-triphenylmethane) and 2-(2′-hydroxy-5′-
A microcapsule liquid was obtained in the same manner as in Example 1, except that diisopropylnaphthalene in which 2% by weight of methylphenylbenzotriazole was dissolved was used. Further, in the same manner as in Example 1, a pressure-sensitive copying paper coated with a microcapsule liquid was prepared. The microcapsule liquid is white, and the pressure-sensitive copying paper is also white (reflection density value 0.06).The coated surface was exposed to room light for 48 hours (hereinafter, light exposure is
Even under these conditions (unless otherwise specified), almost no blue-purple coloration was observed (reflection density value 0.08). Example 14 4% by weight of 4,4'-dimethylamino-3'-methyl-4''-ethoxy-triphenylmethane and p-
A microcapsule liquid and a pressure-sensitive copying paper were prepared in the same manner as in Example 13, except that phenylxylylethane in which 1.5% by weight of tert-butyl-phenyl salicylate was dissolved was used. The microcapsule liquid and the pressure-sensitive copying paper were white (reflection density value 0.07), and coloration due to light exposure was extremely small. In Examples 13 and 14, when no ultraviolet absorber was used, the microcapsule surface was colored due to light exposure (indoor light) on the pressure-sensitive copying paper coated surface, and the reflection density value was 0.14 (blue...Example 13). ,0.13
(Green...Example 14). Example 15 10% ethylene maleic anhydride copolymer (trade name
EMA−31…Monsanto Chemical Co.) aqueous solution 85
part and diethylenetriaminepentaacetic acid 2.0
180 parts of water dissolved in 0.3 parts of nitrilotriacetic acid
After adding and dissolving 10 parts of urea, 1 part of resorcinol, 10% caustic soda aqueous solution was added to adjust the pH to 3.3.
It was adjusted to Next, 170 parts of phenylxylylethane in which 5% by weight of 4,4',4''-trisdiethylamino-triphenylmethane was dissolved was added to the aqueous solution, and the mixture was emulsified by high speed rotation using a homomixer. Immediately add 20 parts of formaldehyde aqueous solution and heat to 55°C.
The mixture is polymerized with stirring for 3 hours to form a microcapsule membrane, and then allowed to cool to complete the microencapsulation of the urea formaldehyde resin membrane. Mix 100 parts of this microcapsule liquid, 125 parts of water, 9 parts of starch particles, 1 part of calcium carbonate, and 40 parts of 10% hydroxyethyl ether starch, and adjust the pH to 8.5.
After that, the mixture was coated on high-quality paper using a Mayer bar to a dry coating weight of 3.5 g/m ² and dried to prepare a pressure-sensitive copying paper. The microcapsule liquid was only faintly colored blue, and no coloring was observed on the upper paper coated with the microcapsule liquid. (Reflection density value 0.07) When no sequestering agent was used, the microcapsule liquid was colored blue, and the reflection density value of the top paper was 0.21. Examples 16-19 4,4′-bisdimethylamino-3″-methyl-4″-methoxy-triphenylmethane, 4,4 instead of 4,4′,4″-tris-diethylamino-triphenylmethane ′-bisdimethylamino-2″-methyl-4″-dimethylamino-triphenylmethane,
4,4′-bisdimethylamino-2″-methoxy-
4″-N-benzylamino-triphenylmethane,
bis(1-ethyl-2-methyl-indole-3
Microcapsule liquefaction and pressure-sensitive copying paper were prepared by treating in the same manner as in Example 15 using -yl)-4''-ethoxyphenylmethane. The results are shown in Table 2.

[Table] Example 20 Except that dodecyl diphenyl ether in which 5% by weight of 3,6-bisdiethylamino-9-phenylxanthene and 1% by weight of 2-hydroxy-4-methoxybenzophenone were dissolved was used as the dye solution. A microcapsule liquid and pressure-sensitive copying paper were obtained by processing in the same manner as in Example 15. The microcapsules and pressure-sensitive copying paper were white (reflection density value 0.07), and almost no red coloration was observed due to exposure to indoor light. When 2-hydroxy-4-methoxybenzophenone was not used, the microcapsule liquid and pressure-sensitive copying paper were white (reflection density value 0.07), but they were colored red when exposed to light ( Reflection density value 0.13). Example 21 A higher alkyl amide of ethylenediaminetetraacetic acid (trade name Chrest MZ -4...0.8 parts (manufactured by Chrest Chemical) and 25 parts of terephthalic acid chloride were uniformly dissolved in 4 parts of polyvinyl alcohol and pyrophosphoric acid.
Mix 0.1 part with 250 parts of water, mix and emulsify with a homomixer, and maintain at 25°C. Next, 0.5 part of ethylene diamine, hexamethylene diamine
A homogeneous solution of 10 parts of NaOH, 10 parts of NaOH, and 75 parts of water is gradually added dropwise to cause a polyamide film-forming reaction between terephthalic acid chloride and amines at the water-oil interface to complete microencapsulation. The microcapsule liquid was white, and the pressure-sensitive copy paper obtained in the same manner as in Example 15 was also white, with a reflection density value of 0.06 on the coated surface. When no sequestering agent was used, the microcapsule liquid was colored slightly blue, and the paper coated with the microcapsule liquid also had a bluish tinge, with a reflection density value of 0.12. Example 22 3% by weight of crystal violet lactone and 4,4'-dimethylamino-4''-N as pigments
-Phenyl-N-methyl-triphenylmethane
The procedure of Example 1 was repeated except that 1.5% by weight of diisopropylnaphthalene was used to microencapsulate the dye and prepare a pressure-sensitive copying paper. The microcapsules and pressure-sensitive copying paper were white, and the reflection density value of the coated surface was 0.06. The microcapsule liquid without the use of a sequestering agent was colored blue, and the reflection density value of the coated surface of the upper paper was 0.13.

Claims (1)

[Claims] 1. In the dye microcapsule liquid for recording materials, the general formula () (In the formula, X, Y, and Z are a phenyl group that may have a substituent, a naphthyl group that may have a substituent, a β-styryl group that may have a substituent, or an aromatic group that may have a substituent. A methine dye represented by a heterocyclic ring residue, which may be the same or different, and two of X, Y, and Z may be bonded to form a ring. and a metal ion sequestrant. 2. A dye microcapsule liquid for a recording material according to claim 1, wherein the microcapsule liquid contains an ultraviolet absorber.