JPH04211987A - Color developer composition, production of water dispersion thereof, and pressure-sensitive copying paper - Google Patents

Abstract

PURPOSE:To improve initial color forming properties by containing a color developer mainly composed of a nuclear sbstd. salicylate shown by a general formula I and a sbstd. amide shown by a specific general formula. CONSTITUTION:As a sbstd. salicylate shown by a general formula I (in the formula, R1, R2, R3, and R4 are hydrogen atom, halogen atom, 1-15C alkyl, cycloalkyl, phenyl, nuclear sbstd. phenyl, aralkyl, or nuclear substd. aralkyl, which may be the same or different; adjacent two groups out of R1, R2, R3, and R4 may bond with each other to form a ring; (n) is an integer 1 or more; and (m) is a multivalent metal atom), a multivalent metallic salt superior in color developing properties is used, such as 3-methyl-5-isononyl salicylic acid or 3-methyl-5- isododecyl salicylic acid. As a substd. amide shown by a general formula II (in the formula, R5 is hydrogen atom, alkyl which may have substituent, cycloalkyl, phenyl which may have substituent, alkenyl, or aralkyl which may have substituent; R6, R7 are hydrogen atom, alkyl which may have substituent, cycloalkyl, phenyl which may have substituent, alkenyl, or aralkyl which may have substituent, which may be the same or different; and R6, R7 may form a morpholine ring with an adjacent nitrigen atom),N,N-di(ethylhexyl)formamide, N,N- dicyclohexyl formamide, and the like may be used. The color developer shown by the general formula I and the substd. amide shown by the general formula II are dissolved in an organic solvent. This organic solution is emulsified and dispersed in an aqueous medium to produce a water dispersion of the color developer composition. As the dispersing agent, an alkali salt of alkyl nitrate or the like is used.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color developer composition, a method for producing an aqueous dispersion thereof, and a pressure-sensitive copying paper coated with a coating solution containing the same, which exhibits excellent initial color development.

0002

[Prior Art] Pressure-sensitive copying paper uses an electron-donating organic coloring agent (
The upper paper is coated on one side of a support with a color former capsule composition mainly composed of microcapsules encapsulating an oil-based substance in which a color former (hereinafter simply referred to as a color former) is dissolved, and one side of the support is contacted with the above color former. an inner sheet coated with a color developer composition containing an electron-accepting color developer (hereinafter simply referred to as a color developer) as a main component and a color former capsule composition coated on the opposite side; There are various types of sheets such as a bottom paper coated with a color developer composition on one side of a support, and they are generally used as a copying set by combining the top paper-bottom paper or the top paper-middle paper-bottom paper in this order. Also known is a self-coloring type pressure-sensitive copying paper which allows pressure-sensitive copying on one sheet by coating a coloring agent and a color developer on the same side of a support.

Coloring agents for pressure-sensitive copying paper include inorganic coloring agents such as acid clay, activated clay, attapulgite, zeolite, bentonite, silica, aluminum silicate, and phenol-aldehyde polymers and phenol-acetylene. Organic coloring agents such as phenol polymers such as polymers, polyvalent metal salts of aromatic carboxylic acids or derivatives thereof are known.

[0004] Among these, organic coloring agents are more expensive than inorganic coloring agents.
It has the advantage that it has high coloring ability and that the density of the obtained colored image does not decrease due to moisture adhesion or normal file storage. However, there is a drawback that the color density immediately after printing is low and it takes time to reach the saturation density (so-called defect of poor initial color development), and an improvement has been desired. Conventionally, as a method to overcome this drawback, a method has been used to reduce the viscosity of an oily substance that dissolves the color former to accelerate the contact between the color former and the color former. However, since the viscosity of the oily substance increases, especially under low temperature conditions, such methods have not yielded satisfactory results.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a pressure-sensitive copying paper with excellent initial color development.

[0006]

[Means for Solving the Problems] The present invention is based on the general formula [Chemical formula 1]
This is a color developer composition containing a color developer whose main component is a nuclear-substituted salicylate represented by the following formula, and a compound represented by the general formula [Formula 2].

[0007]

[Chemical formula 1]

[In the formula, R1, R2, R3, and R4 may be the same or different, hydrogen atom, halogen atom, alkyl group having 1 to 15 carbon atoms, cycloalkyl group,
a phenyl group, a nuclear-substituted phenyl group, an aralkyl group, or a nuclear-substituted aralkyl group, and R1
, R2, R3, and R4 may be bonded to each other to form a ring. n is an integer of 1 or more, and M represents a polyvalent metal atom. ]

[0009]

[Case 2]

[In the formula, R5 is a hydrogen atom, an alkyl group that may have a substituent, a cycloalkyl group, a phenyl group that may have a substituent, an alkenyl group, or a substituent. Indicates an aralkyl group. In addition, R6 and R7 have a hydrogen atom which may be the same or different, an alkyl group which may have a substituent, a cycloalkyl group, a phenyl group which may have a substituent, an alkenyl group, or a substituent. R6 and R7 may form a morpholine ring together with adjacent nitrogen atoms. ] The present invention also provides a color developer mainly composed of a nuclear-substituted salicylate represented by the above general formula [Chemical formula 1] and a compound represented by the above general formula [Chemical formula 2], which are dissolved in an organic solvent. A method for producing an aqueous dispersion of a color developer composition obtained by emulsifying and dispersing a solution in an aqueous medium with or without heating, then heating the dispersion to remove the organic solvent by distillation, and this method This is an aqueous dispersion of a color developer composition manufactured by

Further, the present invention is a pressure-sensitive copying paper prepared by coating a support with a coating liquid containing the developer composition or an aqueous dispersion of the developer composition.

0012

[Operation] The reason why pressure-sensitive copying paper with excellent initial color development can be obtained in the present invention is not necessarily clear, but the general formula [Chemical formula 2]
This is thought to be due to the lone pair electron of the nitrogen atom in the compound forming a chelate bond to the metal atom of the substituted salicylate, thereby making part of the crystal structure of the substituted salicylate amorphous. As a result, it is presumed that a pressure-sensitive copying paper with improved adsorption and compatibility with an oily substance containing a color former and extremely excellent initial color development ability can be obtained.

All of the substituted salicylates represented by the general formula [Chemical formula 1] have excellent color developing ability, and typical examples include 3-methyl-5-isononylsalicylic acid and 3-methyl-5- Isododecylsalicylic acid, 3-methyl-5-isopentadecylsalicylic acid, 3-methyl-5-(α-methylbenzyl)salicylic acid, 3-methyl-5-(α,α-
dimethylbenzyl) salicylic acid, 3,5-disecandabutylsalicylic acid, 3,5-ditertiarybutyl-6-
Methylsalicylic acid, 3-tert-butyl-5-phenylsalicylic acid, 3,5-ditertiaryamylsalicylic acid, 3-cyclohexyl-5-isononylsalicylic acid, 3
-Phenyl-5-isononylsalicylic acid, 3-(α-methylbenzyl)-5-isononylsalicylic acid, 3-isopropyl-5-isononylsalicylic acid, 3-isononylsalicylic acid, 3-isononyl-5-methylsalicylic acid,
3-isononyl-5-cyclohexylsalicylic acid, 3-
Isononyl-5-phenylsalicylic acid, 3-isononyl-5-(α-methylbenzyl)salicylic acid, 3-isononyl-5-(4,α-dimethylbenzyl)salicylic acid,
3-isononyl-5-(α,α-dimethylbenzyl)salicylic acid, 3-(α,α-dimethylbenzyl)-5-isononylsalicylic acid, 3-isononyl-6-methylsalicylic acid, 5-isononylsalicylic acid, 3- Tertiarybutyl-5-isononylsalicylic acid, 3,5-diisononylsalicylic acid, 3-isododecylsalicylic acid, 3-isododecyl-5-methylsalicylic acid, 3-isododecyl-
6-Methylsalicylic acid, 3-isopropyl-5-isododecylsalicylic acid, 3-isododecyl-5-ethylsalicylic acid, 5-isododecylsalicylic acid, 3-isopentadecylsalicylic acid, 3-isopentadecyl-5-methylsalicylic acid, 3- Isopentadecyl-6-methylsalicylic acid, 5-isopentadecylsalicylic acid, 3,5-dicyclohexylsalicylic acid, 3-cyclohexyl-5-(
α-Methylbenzyl)salicylic acid, 3-phenyl-5-
(α-methylbenzyl)salicylic acid, 3-phenyl-5
-(α,α-dimethylbenzyl)salicylic acid, 3-(α
-methylbenzyl)salicylic acid, 3-(α-methylbenzyl)-5-methylsalicylic acid, 3-(α-methylbenzyl)-6-methylsalicylic acid, 3-(α-methylbenzyl)-5-phenylsalicylic acid, 3, 5-di(α-methylbenzyl)salicylic acid, 3-(α-methylbenzyl)-5-(α,α-dimethylbenzyl)salicylic acid, 3
-(α-methylbenzyl)-5-bromosalicylic acid, 3
-(α,4-dimethylbenzyl)-5-methylsalicylic acid, 3,5-di(α,4-dimethylbenzyl)salicylic acid, 3-(α,α-dimethylbenzyl)-5-methylsalicylic acid, 3-(α , α-dimethylbenzyl)-6-methylsalicylic acid, 3,5-di(α,α-dimethylbenzyl)salicylic acid, 5-(4-mesitylmethylbenzyl)
Salicylic acid, benzylated styrenated salicylic acid, pinenated salicylic acid, 2-hydroxy-3-(α,α-dimethylbenzyl)-1-naphthoic acid or 3-hydroxy-7
Examples include polyvalent metal salts such as -(α,α-dimethylbenzyl)-2-naphthoic acid. Specific examples of the polyvalent metal include magnesium, calcium, zinc, aluminum, iron, cobalt, nickel, etc., with zinc being the most preferred. These may be used alone or in combination.

[0014] Here, the isononyl group, isododecyl group, and isopentadecyl group are defined as general terms for substituents formed by addition of propylene trimer, propylene tetramer, 1-butene trimer, and propylene pentamer, respectively. do. In the general formula [Formula 1], at least one of R1 or R3 is an isononyl group, an isododecyl group, or an isopentadecyl group, which is preferable because the coloring ability is unlikely to deteriorate even when the pressure-sensitive copying paper is exposed to sunlight. .

Some of these substituted salicylates are crystalline when used alone, and their softening points also vary. In order to prepare a color developer that is non-crystalline and has a preferred softening point, the components are mixed appropriately and adjusted to obtain the desired physical properties. Incidentally, if the softening point of the color developer is too low, the color developer applied to the paper surface and dried will penetrate between the paper fibers, lowering the color density, and the aqueous dispersion of the color developer will also tend to coagulate. , lacks long-term storage stability. On the other hand, if the softening point of the color developer is extremely high, it will exhibit almost no self-adhesive action when applied to the paper surface and dried, so a large amount of adhesive must be used to make it stick to the paper surface. In that case, the adhesive may form a film that may impede the transfer of the dye-dissolving oil present in the microcapsules, resulting in a slightly inferior color developing ability. For these reasons, the softening point range of the color developer is preferably 20°C or higher, more preferably 30°C to 85°C.
That's about it.

[0016] As a method for adjusting the softening point of the color developer to a preferred temperature, the first method is to mix color developers with different softening points, and the second method is to lower the softening point of the color developer. Adding substances that lower the softening point, such as metal salts of fatty acids, trialkylphenols, trialkylphenols, or styrene oligomers; and thirdly, adding substances that increase the softening point to color developers whose softening points are too low. , for example, adding polystyrene, poly-α-methylstyrene, petroleum resin, or the like. The mixing ratio is not particularly limited. In addition, the softening point as used in the present invention refers to the softening temperature in a state where the color developer contains equilibrium moisture in water. Usually, the softening point is about 50°C lower than the softening point in a dry state.

[0017] In the present invention, specific substituted amides are used in combination with the above color developer, and specific examples of such substituted amides include N,N-di(2-ethylhexyl)formamide, N,N- Dicyclohexylformamide, N,N-
Diphenylformamide, N,N-dibutylacetamide, N,N-dioctylacetamide, N,N-di(2
-ethylhexyl)acetamide, N-[3-(2-ethylhexyloxy)propyl]acetamide, N,N
-dicyclohexylacetamide, N,N-diphenylacetamide, N,N-dibenzylacetamide, N,
N-di(2-ethylhexyl)propioamide, N,N
-dicyclohexylpropioamide, N,N-diethylcaprylamide, N,N-dibutylcaprylamide, N
, N-di(2-ethylhexyl)caprylamide, N,
N-dicyclohexylcaprylamide, N,N-dimethyllauroylamide, N,N-diethyllauroylamide, N,N-dibutyllauroylamide, N-(2-ethylhexyl)lauroylamide, N,N-di(2-ethylhexyl) lauroylamide, N-lauryl lauroylamide, N,N-diallyl lauroylamide, N,
N-Dicyclohexyllauroylamide, N,N-dimethylmyristoylamide, N,N-diethylmyristoylamide, palmitoylamide, N,N-dimethylpalmitoylamide, N,N-diethylpalmitoylamide, stearoylamide, N,N-dimethylstearoyl amide, N,N-diethylstearoylamide, oleoylamide, N,N-dimethyloleoylamide, N,
N-diethyloleoylamide, N,N-dibutyloleoylamide, N,N-dibutylphenoxyacetamide, N,N-di(2-ethylhexyl)phenoxyacetamide, N,N-dibutylbenzoylamide, N,N
-di(2-ethylhexyl)benzoylamide, N,N
-dibutylphenylacetamide, N,N-di(2-ethylhexyl)phenylacetamide, N,N-di(2
-ethylhexyl)cyclohexamide, N,N-diethylbenzamide, lauroylmorpholide, caprylmorpholide, or oleoylmorpholide. Of course, it is not limited to these. The above compounds may be used alone or in combination. Among these, in the general formula [Chemical formula 2], R5 is an alkyl group having 1 to 17 carbon atoms or an alkenyl group having 2 to 17 carbon atoms, and R6, R
Disubstituted amide compounds in which 7 is each an alkyl group having 1 to 8 carbon atoms or a cyclohexyl group are preferred, particularly N
, N-di(2-ethylhexyl)acetamide, N,N
-dicyclohexylacetamide, N,N-diethyllauroylamide, N,N-dibutyllauroylamide,
N,N-dimethyloleoylamide, N,N-diethyloleoylamide, and N,N-dibutyloleoylamide are preferred.

If a large amount of the compound represented by the above general formula [Chemical formula 2] is blended, the coloring performance of the resulting coloring paper for pressure-sensitive copying paper may deteriorate, or the surface of the coloring agent layer may become sticky, causing problems during printing. Preferably 0.05 to 20 parts by weight, more preferably 0.1 to 10 parts by weight per 100 parts by weight of the substituted salicylate represented by the general formula [Chemical formula 1] on a dry weight basis. Approximately parts by weight of the compound represented by the general formula [Chemical formula 2] are contained in the coating liquid for colored paper.

In order to prepare a color developer dispersion, it is preferable to dissolve a color developer represented by the general formula [Formula 1] in an organic solvent and emulsify and disperse the solution in an aqueous medium. Organic solvents are required to have various properties such as relatively low solubility in water, good solubility in color developer, low boiling point, and resistance to chemical changes during the preparation of dispersions. Ru. At this time, if the compound represented by the general formula [Chemical formula 2] is also dissolved in an organic solvent, there is an advantage that the preparation work becomes easier.

Specific examples of organic solvents include benzene, toluene, xylene, chloroform, carbon tetrachloride, trichloroethane, chlorobenzene, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate,
Examples include butanol, amyl alcohol, methyl tert-butyl ether, and the like. The amount of organic solvent used is
Although it is appropriately adjusted depending on the intended size of the dispersed particles, it is desirable to adjust it within a range of about 500 parts by weight or less per 100 parts by weight of the color developer.

In the method for producing an aqueous dispersion of a color developer composition of the present invention, a specific color developer and a compound represented by the general formula [Formula 2] are dissolved in an organic solvent as described above, and then this organic solvent is The solution is emulsified and dispersed in an aqueous medium. Dispersants used when emulsifying and dispersing in an aqueous medium include, for example, alkali salts of alkyl sulfates, alkali salts of alkylbenzenesulfonic acids, alkali salts of alkylnaphthalenesulfonic acids, alkali salts of oleic acid amide sulfonic acids, and dialkyl sulfosuccinic acids. anionic surfactants such as alkali salts, polyoxyethylene alkyl ethers,
Nonionic surfactants such as polyoxyethylene fatty acid ester, gum arabic, sodium alginate, agar,
Natural polymer substances such as gelatin, carboxymethyl cellulose, hydroxyethyl cellulose, carboxymethylated starch, phosphorylated starch, semi-synthetic polymer substances such as sodium lignin sulfonate, methyl vinyl ether/maleic anhydride copolymer, ethylene/maleic anhydride Polymers and copolymers such as copolymers, styrene/maleic anhydride copolymers, acrylic acid polymers, acrylic acid/methyl methacrylate copolymers, acrylic acid/acrylamide copolymers, vinylbenzenesulfonic acid polymers, etc. Synthetic polymer substances such as alkali salts of , polyvinyl alcohol, polyacrylamide, vinyl carboxylic acid ester/acrylamide copolymers, etc. are included, but in the method of the present invention, vinyl carboxylic acid ester/acrylamide copolymers are particularly used. preferable. In particular, the degree of polymerization is 100 or more, at least 70 to 96 mol% of acrylamide and acrylic acid,
Alkyl or alkoxyalkyl ester of methacrylic acid, itaconic acid or maleic acid having 4 or less carbon atoms 4 to 30
Acrylamide copolymers having a copolymerization ratio of mol % are particularly preferred because they have high protective colloidal properties and low foaming properties. In addition, even if these dispersants are used alone,
Two or more types may be used in combination.

[0022] The amount of these dispersants to be used is appropriately adjusted depending on the intended size of the dispersed particles, etc., but is preferably adjusted at a ratio of about 1 to 30 parts by weight per 100 parts by weight of the color developer. Ru. The aqueous dispersion of the color developer thus prepared is
By the heat treatment, the organic solvent is removed by distillation, and an aqueous dispersion of the color developer composition consisting of truly spherical particles is prepared.

The color developer composition aqueous dispersion thus obtained can be further subjected to a dispersion treatment. Examples of dispersing machines include ball mills, pebble mills, sand grinders (vertical and horizontal), various sand mill type mills that use grinding media such as Kobol Mill, Attritor, and Dyno Mill, three-roll mills, high-speed impeller dispersers, and high-speed stones. Examples include high-speed grinding devices such as mills and high-speed impact mills, but sand mill type grinders (vertical type, horizontal type) and high-speed impeller dispersion machines are preferable in consideration of ease of setting processing conditions, grinding efficiency, etc. A sand mill type pulverizer (vertical type, horizontal type) is more preferable.

Generally, the concentration of the color developer in the aqueous dispersion is 1
High concentrations of 0% or higher are possible, with a preferred upper limit of 55%
That's about it. Such a high concentration not only reduces transportation costs, but also makes it possible to prepare a highly concentrated coating solution, increasing drying efficiency in the coating process and improving the quality of the resulting colored paper for pressure-sensitive copying paper. You can also expect

[0025] In the coating liquid forming the color developer layer, an adhesive such as starch, casein, gum arabic, carboxymethyl cellulose, or polyvinyl alcohol is usually added to the color developer composition dispersion thus obtained. , styrene-butadiene copolymer latex, vinyl acetate latex, etc., and inorganic pigments such as zinc oxide, magnesium oxide, titanium oxide, aluminum hydroxide, calcium carbonate, magnesium sulfate, calcium sulfate, and pressure-sensitive pigments. Various auxiliary agents known in the field of copying paper manufacturing may be added as appropriate.

The coating liquid for the developer layer thus prepared is applied to high-quality paper, coated paper, synthetic paper, etc. using a conventional coating device such as an air knife coater, blade coater, roll coater, size press coater, curtain coater, or short dwell coater. It is coated onto a support such as paper or film and finished as pressure-sensitive copying paper. The amount of coating liquid for the developer layer applied to the support is not particularly limited, but is 2 to 8 g in dry weight.
/m2.

[0027] The color developer composition and color developer composition aqueous dispersion of the present invention may have a color developer layer and a color former layer on the same side of a support, or a color developer coating liquid and a capsule. Of course, the present invention can also be applied to self-coloring type pressure-sensitive copying paper (so-called self-containing type) having a mixed coating layer of a coating liquid containing a colored coloring agent.

[0028]

[Preparation of developer composition aqueous dispersion]

2000 g of water and 400 g of zinc sulfate (7-hydrate salt) are placed in a 20000 ml stainless steel cylindrical container equipped with a stirrer and a thermometer, and dissolved. To this was added 8500 g of a 10% aqueous solution of sodium 3,5-di(α-methylbenzyl)salicylate while stirring the contents vigorously. Due to double decomposition, the inside of the container immediately becomes a thixotropic liquid. Here α
- Copolymer of methylstyrene and styrene (copolymerization ratio: 4
0:60 mole percent, average molecular weight; approximately 1500) 1
50 g and 20 g of N,N-dicyclohexylacetamide
900 g of methyl isobutyl ketone solution containing g are added in a short time. The fluidity of the thixotropic, thick contents gradually improves, so when it becomes easy to flow, heat the container to bring the temperature of the contents to 75° C. and leave it standing. The aqueous phase is separated into the upper layer and the oil phase is separated into the lower layer, so take out the entire amount of the oil layer and transfer it to a hard glass beaker with an internal volume of 5000 ml. In addition, 600 g of water, 2.5 g of sodium carbonate, and 500 g of a 5% aqueous solution of polyvinyl alcohol (degree of saponification: 98%, degree of polymerization: approximately 1700)
g, and 60 g of a 25% aqueous solution of a copolymer of ethyl acrylate and acrylamide (copolymerization ratio: 13:87 mole percent, degree of polymerization: about 400), and heated at 35°C to 40°C.
An oil-in-water emulsion is obtained by carrying out an emulsification operation for 20 minutes at a rotation speed of 8,800 to 9,000 times per minute using a homomixer (model M, manufactured by Tokushu Kika Kogyo Co., Ltd.) at a temperature in the range of .degree. Transfer this to a hard glass three-necked flask with an internal volume of 10,000 ml and equipped with a stirrer, thermometer, and distillation port, add 2,000 g of water, and heat the flask to boil while stirring the contents slowly. When methyl isobutyl ketone and some water are removed from the distillation port, the contents become an emulsion containing no methyl isobutyl ketone and having a total solid content of 38%. The average particle diameter of the obtained developer-dispersed particles was 2.0 μm. The softening point of the dispersed phase is 78°C.

[Preparation of color developer coating liquid] 38% color developer composition aqueous dispersion 1 obtained by the above treatment
8 parts of calcium carbonate, 94 parts of calcium carbonate, and 100 parts of water were mixed and dispersed, and further, as a binder, 50 parts of a 10% polyvinyl alcohol aqueous solution and 50% carboxy-modified SBR latex (SN-307, manufactured by Sumitomo Naugatac) 1
A developer coating solution was prepared by mixing and dispersing 0 parts.

[Manufacture of developer paper for pressure-sensitive copying paper] The above developer coating liquid was applied to one side of a base paper of 40 g/m2 so that the dry weight was 5 g/m2, and dried to form a developer for pressure-sensitive copying paper. I got colored paper.

Example 2 A color developer composition aqueous dispersion was prepared in the same manner as in Example 1 except that 20 g of N,N-diethyl lauroylamide was used instead of 20 g of N,N-dicyclohexylacetamide. was prepared. The average particle diameter of the obtained developer-dispersed particles was 1.5 μm (total solid content: 38%).

A developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1.

Example 3 The aqueous dispersion of the color developer composition obtained in Example 1 was processed in a horizontal sand mill (Grain Mill GMH-S20M, manufactured by Asada Tekko Co., Ltd.) at a rate of 3 kg per minute to form a water dispersion of the color developer composition. A liquid was prepared. The average particle diameter of the obtained developer-dispersed particles was 1
．． 8μ (total solid content 38%). Thereafter, a developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1.

Example 4 The aqueous dispersion of the color developer composition obtained in Example 2 was subjected to a sand grinder (manufactured by Igarashi Kikai Co., Ltd., MODEL
NO, OSG-8G) at a rate of 2 kg per minute,
A color developer composition aqueous dispersion was prepared. The average particle diameter of the obtained developer-dispersed particles was 1.4 μm (total solid content: 38%).

A developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 2.

Example 5 1000 g of zinc 3-isododecylsalicylate and 700 g of toluene were mixed and dissolved at 50° C. to prepare a toluene solution. 20 g of N,N-diethyl lauroylamide is added and dissolved in this toluene solution. This toluene solution has an internal volume of 50
Transfer to a 00ml stainless steel beaker, add 600g of water, 2.5g of sodium carbonate, and a copolymer of ethyl acrylate and acrylamide (copolymerization ratio: 13:8).
7 mol percent, degree of polymerization; approximately 400) 25% aqueous solution 1
00 g was added and emulsified for 20 minutes at 8,800 to 9,000 revolutions per minute using a homomixer (Model M, manufactured by Tokushu Kika Kogyo Co., Ltd.) at a temperature of 35°C to 40°C to form an oil-in-water type. An emulsion of . This has an internal volume of 1 with a stirrer, thermometer and distillation port.
Transfer to a 0,000 ml hard glass three-necked flask,
Add another 2000 g of water and heat the flask to a boil while stirring the contents slowly. When about 700 g of toluene and about 650 g of water are taken out from the distillation port,
The contents will be an emulsion containing no toluene and having a total solids content of 38%. The average particle diameter of the obtained developer-dispersed particles was 1.5.
It was μ. The softening point of the dispersed phase is 63°C.

Next, this dispersion was placed in a sand grinder (manufactured by Igarashi Kikai Co., Ltd., MODEL NO, OSG-8G).
) at a rate of 2 kg per minute, with an average particle size of 1.4
A developer dispersion of μ was prepared. Thereafter, a developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1.

Example 6 Zinc 3,5-di(α-methylbenzyl)salicylate 50
0 g and a copolymer of α-methylstyrene and styrene (copolymerization ratio: 40:60 mole percent, average molecular weight: approximately 1
500) A toluene solution is prepared by mixing and dissolving 150 g of zinc 3-isododecylsalicylate, 350 g of zinc 3-isododecylsalicylate, and 700 g of toluene at 50°C. In this toluene solution, N
, N-diethyl lauroylamide (20 g) was added and dissolved. Separately, in a stainless steel beaker with an internal volume of 5000 ml, add 600 g of water, 2.5 g of sodium carbonate,
Copolymer of ethyl acrylate and acrylamide (copolymerization ratio: 13:87 mol percent, degree of polymerization: about 400) 2
By adding 100 g of a 5% aqueous solution and performing an emulsification operation for 20 minutes at 8,800 to 9,000 revolutions per minute using a homomixer (Model M, manufactured by Tokushu Kika Kogyo Co., Ltd.) in the range of 35 to 40 °C. An oil-in-water emulsion is obtained. Transfer this to a hard glass three-necked flask with an internal volume of 10,000 ml and equipped with a stirrer, thermometer, and distillation port, add 2,000 g of water, and heat the flask to boil while stirring the contents slowly. When about 700 g of toluene and about 650 g of water were taken out from the distillation port, the contents were 38% of total solids excluding toluene.
% emulsion. The average particle diameter of the obtained developer-dispersed particles was 2.1 μm. The softening point of the dispersed phase is 73°C. Thereafter, a developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 2.

Example 7 A color developer composition aqueous dispersion was prepared in the same manner as in Example 1 except that 30 g of N,N-dibutyl lauroylamide was used instead of 20 g of N,N-dicyclohexylacetamide. was prepared. The average particle diameter of the obtained developer-dispersed particles was 1.2 μm (total solid content: 38%). Thereafter, a developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1.

Example 8 The aqueous dispersion of the color developer composition obtained in Example 7 was processed in a horizontal sand mill (Grain Mill GMH-S20M, manufactured by Asada Tekko Co., Ltd.) at a rate of 4 kg per minute to obtain a color developer composition. An aqueous dispersion was prepared. The average particle diameter of the obtained developer-dispersed particles was 1.0 μm (total solid content: 38%).

A developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 7.

Example 9 A developer composition was dispersed in water in the same manner as in Example 1 except that 30 g of N,N-dimethyloleoylamide was used instead of 20 g of N,N-dicyclohexylacetamide. A liquid was prepared. The average particle diameter of the obtained developer-dispersed particles was 1.4 μm (total solid content: 38%). Thereafter, a developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1.

Comparative Example 1 A developer composition aqueous dispersion was prepared in the same manner as in Example 1 except that 20 g of N,N-dicyclohexylacetamide was not used. The average particle diameter of the obtained developer-dispersed particles was 2.4 μm (total solid content: 38%). Developing paper for pressure-sensitive copying paper was obtained in the same manner.

Comparative Example 2 In Example 5, an aqueous color developer composition dispersion was prepared without using 20 g of N,N-diethyl lauroylamide. The average particle diameter of the obtained developer-dispersed particles was 1.7 μm (total solid content: 38%). A developer paper for pressure-sensitive copying paper was obtained in the same manner.

Comparative Example 3 Instead of using 20 g of N,N-dicyclohexylacetamide in Example 1, 2,2'-methylenebis(
A developer composition aqueous dispersion was prepared in the same manner except that 4-methyl-6-tert-butylphenol) was used. The average particle diameter of the obtained developer-dispersed particles was 1.9 μm (total solid content: 38%). A developer paper for pressure-sensitive copying paper was obtained in the same manner.

Comparative Example 4 Instead of using 20 g of N,N-dicyclohexylacetamide in Example 1, triethylene glycol-
Bis[3-(3-tert-butyl-5-methyl-4-
An aqueous developer dispersion was prepared in the same manner except that 20 g of hydroxyphenyl propionate was used.

The average particle diameter of the obtained developer-dispersed particles was 2.
．． 9μ (total solid content 38%). A developer paper for pressure-sensitive copying paper was obtained in the same manner.

The following quality evaluation tests were conducted on the 13 types of color developer paper for pressure-sensitive copying paper thus obtained, and the results are shown in Table 1. [Preparation of top paper] A capsule coating liquid prepared by dissolving crystal violet lactone in alkylated naphthalene and microcapsulating this oily liquid was coated on one side of high-quality paper with a dry weight of 4 g/m2.
2 and dried to obtain upper paper.

Low-temperature color development test The developer paper and upper paper were left in an atmosphere at 1° C. for 10 hours. Next, the coated surfaces of the colored paper and top paper were placed opposite each other in an atmosphere of 1°C using a drop-type coloring tester (weight: 150 g, height:
10 cm), and the color density was measured using a Macbeth reflection densitometer 10 seconds after the impact and 1 day later.

[0050]

[Table 1]

[0051]

[Effects of the Invention] As is clear from the results in Table 1, the color developer paper for pressure-sensitive copying paper of the present invention had excellent properties in low-temperature color development, particularly in initial color development.

Claims (4)

[Claims] [Claim 1] A color developer composition comprising a color developer whose main component is a nuclear-substituted salicylate represented by the general formula [Chemical formula 1], and a compound represented by the general formula [Chemical formula 2]. [Formula 1, R1, R2, R3, and R4 are hydrogen atoms or halogen atoms, which may be the same or different, and have 1 to 1 carbon atoms]
Alkyl group, cycloalkyl group, phenyl group up to 5,
A nuclear-substituted phenyl group, an aralkyl group, or a nuclear-substituted aralkyl group, and R1, R2, R3
, and R4 may be bonded together to form a ring. n is an integer of 1 or more, and M represents a polyvalent metal atom. [Formula 2] [In the formula, R5 is a hydrogen atom, an alkyl group that may have a substituent, a cycloalkyl group, a phenyl group that may have a substituent, an alkenyl group, or a substituent Indicates a good aralkyl group. In addition, R6 and R7 are hydrogen atoms which may be the same or different, alkyl groups which may have substituents,
cycloalkyl group, phenyl group which may have a substituent,
It represents an alkenyl group or an aralkyl group which may have a substituent, and R6 and R7 may form a morpholine ring together with adjacent nitrogen atoms. ] [Claim 2] A color developer mainly composed of a nuclear-substituted salicylate represented by the general formula [Chemical formula 1] and a compound represented by the general formula [Chemical formula 2] are dissolved in an organic solvent, and this solution is dissolved in an aqueous solution. A method for producing an aqueous dispersion of a color developer composition obtained by emulsifying and dispersing it in a medium with or without heating, and then heating the dispersion to distill off the organic solvent. [Formula 1, R1, R2, R3, and R4 are hydrogen atoms or halogen atoms, which may be the same or different, and have 1 to 1 carbon atoms]
Alkyl group, cycloalkyl group, phenyl group up to 5,
A nuclear-substituted phenyl group, an aralkyl group, or a nuclear-substituted aralkyl group, and R1, R2, R3
, and R4 may be bonded together to form a ring. n is an integer of 1 or more, and M represents a polyvalent metal atom. [Formula 2] [In the formula, R5 is a hydrogen atom, an alkyl group that may have a substituent, a cycloalkyl group, a phenyl group that may have a substituent, an alkenyl group, or a substituent Indicates a good aralkyl group. In addition, R6 and R7 are hydrogen atoms which may be the same or different, alkyl groups which may have substituents,
cycloalkyl group, phenyl group which may have a substituent,
It represents an alkenyl group or an aralkyl group which may have a substituent, and R6 and R7 may form a morpholine ring together with adjacent nitrogen atoms. ] 3. An aqueous dispersion of a color developer composition produced by the method according to claim 2. 4. Pressure-sensitive copying paper obtained by coating a support with a coating liquid containing the color developer composition according to claim 1 or the aqueous dispersion of the color developer composition according to claim 3.