JPH03254989A - Production of color developer water dispersion and pressure-sensitive copying paper - Google Patents

Abstract

PURPOSE:To obtain the above pressure-sensitive copying paper superior in resistance to light by a method wherein a coating liquid containing a water dispersion of a color developer mainly composed of a specific ring-substd. salicylate and a specific compound having an ultraviolet absorbing function is applied to a substrate. CONSTITUTION:In pressure-sensitive copying paper, a color developer mainly composed of a ring-substd. salicylate shown by a formula (I) and a compound shown by a formula (II) or/and a formula (III) with a function as an ultraviolet absorber are dissolved in an organic solvent; this solution is emulsified and disposed in an aqueous medium under heated or unheated conditions; and a coating liquid containing a color developer water dispersion obtained by removing the organic solvent by distillation by heating this dispersion is applied to a substrate. In the formulas R1, R2, R3, R4, R5, and R7 are hydrogen atom, alkyl group, cycloalkyl group, phenyl group, and the like; M is magnesium, calcium, zinc, aluminum, iron, cobalt, nickel, or the basic ion of these metals; R6 is alkyl group, alkyl group having substituent, cycloalkyl group, aryl group, or the like; and R8 is alkylene group which may have substituent, diester residue of polyethylene glycol, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a method for producing an aqueous color developer dispersion and a pressure-sensitive copying paper coated with a coating liquid containing the same and having excellent light resistance.

``Prior Art'' Pressure-sensitive copying paper uses a color-forming agent capsule composition, which is mainly composed of microcapsules containing an oil-based substance in which an electron-donating organic coloring agent (hereinafter simply referred to as coloring agent) is dissolved, as a support. An upper paper coated on one side and a color developer composition containing an electron-accepting color developer (hereinafter simply referred to as a color developer) as a main component that develops a color when it comes into contact with the color former on one side of the support. There are various types of sheets, such as an inner paper coated with a color former capsule composition on the opposite side, and a lower paper coated with only a color developer composition on one side of the support. Paper-
It is put into practical use as a copy set by combining the middle paper and the 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.

Known examples of this color developer include clays such as acid clay, activated clay, acpulgite, zeolite, ben I-night, and phenol polymers such as phenol-aldehyde polymers and phenol-acetylene polymers. . However, when clays such as those mentioned above are used as color developers, the clay adsorbs substances in the air during long-term storage, resulting in a marked decline in coloring ability, and colored prints gradually deteriorate over time. It has the disadvantage of discoloration or fading, and also has the disadvantage that if the print gets wet with water, the print density is extremely reduced. On the other hand, phenol polymers have the disadvantage of poor light resistance of printing and yellowing of the color developer layer caused by exposure treatment. For this reason, substituted salicylates, which have excellent performance in various aspects, have attracted attention in place of the above-mentioned acidic substances.

That is, pressure-sensitive copying paper using a substituted salicylate exhibits almost no decrease in coloring ability even after long-term storage. ■Colored prints are relatively difficult to discolor or fade over time. (2) When using a substituted salicylate that is difficult to dissolve in water, the print density hardly decreases even if it gets wet with water. (2) The developer layer has the advantage of not being easily yellowed even after exposure treatment. Furthermore, ■It has very high coloring ability.

(2) It has excellent performance in various aspects, such as print density and coloring ability hardly changing even after processing for several hours at 100°C or higher.

Thus, by using a substituted salicylate as a color developer in place of the color developer described above, the performance of pressure sensitive copying paper was significantly improved.

However, even with pressure-sensitive copying paper using substituted salicylates, it has been observed that when the printed copy paper is exposed to direct sunlight, the copied image fades, and further improvement in light resistance is desired. is the current situation.

"Problems to be Solved by the Invention" An object of the present invention is to solve the above problems and provide pressure-sensitive copying paper with excellent light resistance.

"Means for Solving the Problem" The present invention is based on a color developer whose main component is a nuclear-substituted salicylate represented by the general formula (1), and a color developer having the general formula (n) and/or the general formula [■]. Color developer water obtained by dissolving the compound shown in an organic solvent, emulsifying and dispersing this solution in an aqueous medium with or without heating, and then heating this dispersion to remove the organic solvent by distillation. This is a method for producing a dispersion.

[In formula (1), R1, R2, R, 3, and R6 may be the same or different hydrogen atoms, 2 halogen atoms, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group, a phenyl group, a nucleus a substituted phenyl group, an aralkyl group or a nuclear-substituted aralkyl group, and R +,
Adjacent two of R2, R3 and R4 may be combined to form a ring. n is a number of 1 or more, and M is magnesium, calcium, zinc, aluminum, iron, cobalt, nickel, or a basic ion thereof. ] [In the formula [■], R3 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, a phenyl group, a nuclear-substituted phenyl group, an aralkyl group, or a nuclear-substituted aralkyl group .

R6 is an alkyl group, an alkyl group having a substituent, a cycloalkyl group, an aryl group, a monoester residue of a diol having 12 or less carbon atoms, a mononistyl residue of polyethylene glycol which may have a substituent, or a substituent. The monoester residue of polypropylene glycol which may have a substituent or the monoester residue of polybutylene glycol which may have a substituent is shown. ] [In (, I[[), R7 is a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group,
Represents a phenyl group, a nuclear-substituted phenyl group, an aralkyl group, or a nuclear-substituted aralkyl group.

R8 is an alkylene group which may have a substituent, a diester residue of polyethylene glycol which may have a substituent,
Represents a diester residue of polypropylene glycol which may have a substituent or a diester residue of polybutylene glycol which may have a substituent. ] The present invention also provides a method for producing an aqueous developer dispersion in which the volume average particle diameter of the developer in the aqueous developer dispersion is 5 microns or less.

Further, the present invention is a pressure-sensitive copying paper prepared by coating a support with a coating solution containing the above-mentioned aqueous developer dispersion.

"Function" Although the reason why pressure-sensitive copying paper with excellent light resistance can be obtained in the present invention is not necessarily clear, it is explained by the general formulas CTI) and (I[I
) It is thought that one reason for this is that the compound represented by has a function as an ultraviolet absorber. However, simply adding the compound represented by the general formula [■] and/or [■] to the color developer-containing layer does not provide a sufficient effect, and a color developer dispersion is prepared using the above manufacturing method. Since extremely excellent effects can be obtained when applied to a support, it is thought that the use of an organic solvent in the dispersion preparation process plays an important role.

All of the substituted salicylates represented by the general formula [1] have excellent color developing ability, and a typical example is 3-methyl-
5-(iso)nonylsalicylic acid, 3-methyl-5-(iso)dodecylsalicylic acid, 3- 0-methyl-5-(iso)pentadecylsalicylic acid, 3-
Methyl-5-(α-methylhensyl)salicylic acid, 3-
Methyl-5-(α,α-dimethylbenzyl)salicylic acid, 3,5-disecandabutylsalicylic acid, 3,5-ditertiarybutyl-6methylsalicylic acid, 3-tert-butyl-5phenylsalicylic acid, 3. 5-ditertiaryamylsalicylic acid, 3-cyclohexyl-5-(iso)nonylsalicylic acid, 3-phenyl-5-(iso)nonylsalicylic acid, 3-(α-methylbenzyl)-5-(iso)nonylsalicylic acid, 3-isopropyl-5-(iso)nonylsalicylic acid, 3-(iso)nonylsalicylic acid,
3-(iso)nonyl-5-methylsalicylic acid, 3-(iso)nonyl-5-cyclohexylsalicylic acid, 3-(iso)nonyl-5-phenylsalicylic acid, 3-(iso)nonyl Jl/-5-(α-methyl benzyl) salicylic acid, 3(
Iso)nonyl-5-(4,α-dimethylbenzyl)salicylic acid, 3-(iso)nonyl-5-(α α-dimethylbenzyl)salicylic acid, 3-(α α-dimethylbenzyl)-5-(iso)nonyl Salicylic acid, 5-(iso)nonylsalicylic acid, 3-(iso)nonyl-6-methylsalicylic acid, 3-tert-butyl-5-(iso)nonylsalicylic acid, 3.5-di(iso)nonylsalicylic acid, 3(iso) Dodecylsalicylic acid, 3-(iso)dodecyl-5
-Methylsalicylic acid, 3-(iso)l·decyl-6-
Methylsalicylic acid, 3-isopropyl-5-(iso)dodecylsalicylic acid, 3-(iso)dodecyl-5-ethylsalicylic acid, 5-(iso)dodecylsalicylic acid, 3-(
Iso)pentadecylsalicylic acid, 3-(iso)pentadecyl-5methylsalicylic acid, 3-(iso)pentadecyl 6-methylsalicylic acid, 5-(iso)pentadecylsalicylic acid, 3.5-dicyclohexylsalicylic acid, 3-cyclohexyl- 5-(α-methylbenzyl)salicylic acid, 3-phenyl-5-(α-methylbenzyl)salicylic acid, 3-ph,enyl 5-(α,α-dimethylbenzyl)salicylic acid, 3-(α-methylbenzyl)salicylic acid, l
-(1 2 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-methylhensyl)-5(α,α-dimethylbenzyl)salicylic acid, 3(α-methylbenzyl)-5-bromosalicylic acid, 3-(α,4-dimethyl benzyl)-5-methylsalicylic acid, 3,5-di(α14-dimethylbenzyl)
Salicylic acid, 3-(α,α-dimethylhensyl)-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,
2-hydroxy-3-(α,α-dimethylpencyl)-
Polyvalent metal salts such as 1-naphthoic acid or 3-hydroxy-7-(α,α-dimethylhensyl)-2-naphthoic acid can be mentioned. Specific examples of polyvalent metals include magnesium, calcium, zinc, aluminum, iron, cobalt,
Examples include nickel. These may be used alone or in combination.

Note that (iso)alkyl represents isoalkyl or normal alkyl. Moreover, an isononyl group, an isododecyl group, and an isopentadecyl group are defined as a substituent formed by the addition of a propylene trimer, a propylene tetramer, a 1-butene daimer, and a propylene pentamer, respectively.

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.

If the softening point of the color developer is too low, the color developer applied to the paper surface and dried will penetrate and migrate between the paper fibers, reducing the color density.
Aqueous dispersions of color developers also tend to coagulate and lack long-term storage stability.

On the other hand, if the softening point of the color developer is extremely high,
Since it exhibits almost no self-adhesive effect when dried, a large amount of adhesive must be used to adhere it to the paper surface, in which case the adhesive forms a film and forms microcapsules. This may hinder the transfer of the dye-dissolving oil present in the dye, and the color developing ability may be slightly inferior.

For these reasons, the softening point range of the color developer is preferably 20°C or higher, more preferably about 30°C to 85°C.

The first method to adjust the softening point of the color developer to a desired temperature 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, I-realkylphenols, trialkylphenols, or styrene oligomers; and thirdly, substances that raise the softening point by 1 to a color developer whose softening point is 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. When R6 is an alkyl group among the compounds represented by Table 1 or -format CIII), those having 18 or less carbon atoms are preferred. Examples of the monoester residue of a diol in which R6 has 12 or less carbon atoms include 5-hydroxypentyl group and 8-hydroxyoctyl group, and examples of the alkyl group having a substituent include phenoxyethyl group.

Among the compounds represented by the general formula (III), although not particularly limited, R8 may have a substituent or diester residue 7 of polyethylene glycol. To a lesser extent.

- Among the compounds represented by the formula [■], there are no particular limitations, but the general formula (I
V) is preferred.

[In formula (IV), R9 and R1 may be the same or different; a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, a phenyl group,
Indicates a nuclear-substituted phenyl group, an aralkyl group, or a nuclear-substituted aralkyl group. m represents an integer of 1 or more. ] However, m is not particularly limited, but is usually between 1 and 1.
An integer around 00 is desirable. Specific examples of compounds represented by the -format (IV) include compounds in which R9 and R8° are shown in Table 1.

6 Compounds of the form (v) are preferred.

[[In formula 73, Rz, R, +□ may be the same or different, and are a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, a phenyl group, a nuclear-substituted phenyl group, Indicates an aralkyl group or a nuclear-substituted aralkyl group. p represents an integer of 1 or more. ] However, p is not particularly limited, but is usually an integer of about 1 to 100.

- Specific examples of compounds represented by format (v) include R and RI.
Compounds with the combinations indicated by □ are shown in Table 2.

8 Table 2 Also, when Re is an alkylene group which may have a substituent in the compound represented by the formula (II), an alkylene group having 12 or less carbon atoms is preferable.

The proportion of the compound represented by -Form (II) and/or -Form (III) is variously selected depending on the purpose of use of the color developer, etc., and is not particularly limited; however, if a large amount is blended, This may cause a decrease in the coloring performance of the resulting color-forming paper for pressure-sensitive copying paper or yellowing of the color developer-containing layer.
In terms of dry weight, preferably 0.05 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the substituted salidylate represented by general formula [N], general formula [■] and/ Or - A compound represented by the format [■] is contained in a coating liquid for colored paper.

In the present invention, the organic solvent that dissolves the color developer and the compound represented by -Form [■] and/or -Form (III) has relatively low solubility in water and good solubility of the color developer. It is required to have various properties such as a low boiling point and resistance to chemical changes during the preparation of a dispersion.

Specific examples include benzene, toluene, xylene, chloroform, carbon tetrachloride, trichloroethane, chlorobenzene, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, butanol, amyl alcohol, or methyl tajarybdel ether. Can be mentioned.

The amount of the organic solvent to be used is appropriately adjusted depending on the intended size of the dispersed particles, etc., but it is preferably adjusted within a range of about 500 parts by weight or less per 100 parts by weight of the color developer.

90 When the organic solvent solution thus obtained is emulsified and dispersed in an aqueous medium with or without heating, it is preferable to include an emulsifier in the aqueous medium. Examples of emulsifiers include low molecular weight anionic surfactants such as polyvinyl alcohol, alkali salts of alkyl sulfates, alkali salts of alkyl hanzene sulfonic acids, anionic natural polymers such as gum arabic, acrylic acid polymers, and vinyl benzene sulfates. Examples include alkali salts of anionic polymers such as ponic acid polymers, acrylic acid/acrylamide copolymers, and ethylene/maleic anhydride copolymers. Two or more of these may be used in combination.

The thus prepared aqueous developer dispersion is heated to remove the organic solvent by distillation, thereby preparing an aqueous developer dispersion comprising truly spherical particles.

The obtained aqueous developer dispersion may be subjected to wet pulverization treatment if necessary. Examples of fine grinding machines include ball mills, pebble mills, sand grinders, Kobol mills, attritors, Dyno mills, etc., which use grinding media, three-roll mills, high-speed impeller dispersion machines, high-speed stone mills, and high-speed stone mills. Examples include high-speed grinding devices such as a speed impact mill, but in view of ease of setting processing conditions, grinding efficiency, etc., Zandmill-type pulverizers and high-speed impeller dispersers are preferred, and among these, Zandmill-type pulverizers are more preferred.

If the volume average particle diameter of the color developer particles in the dispersion liquid exceeds 5 microns, the distribution on the paper surface becomes uneven during application, resulting in missing recorded images, or the speed at which recorded images develop in cold regions. In some cases, the initial color development may be poor. Furthermore, if the average particle size is smaller than 0.3 microns, the particles tend to penetrate between the paper fibers, resulting in a loss of color developing action, and there is no advantage in making the particles smaller than that. Therefore, the preferred range of the average particle diameter of the color developer particles is 0.3
-5 microns, with a more preferred range of 0.6-3 microns. Generally, the concentration of the color developer in the aqueous dispersion is usually 1
The concentration is as high as 0% or more, and the preferable upper limit is about 55%. Such a high concentration not only reduces transportation costs, but also makes it possible to prepare a highly concentrated coating solution, which increases drying efficiency in the coating process and improves the quality of the resulting colored paper for pressure-sensitive copying paper. Improvement effects can also be expected.

The coating solution for forming the developer layer of pressure-sensitive copying paper usually contains an adhesive, such as starch, casein, gum arabic, carboxymethylcellulose, polyvinyl alcohol, styrene, etc., in the dispersion thus obtained. Butadiene copolymer latex, vinyl acetate latex, etc. are blended, and inorganic pigments such as zinc oxide, magnesium oxide, titanium oxide, aluminum hydroxide, calcium carbonate, magnesium sulfate, calcium sulfate, etc., and pressure-sensitive copying paper manufacturing Various auxiliaries known in the art can be added as appropriate.

The amount of the developer layer coating liquid applied to the support is not particularly limited, but is approximately 2 to 8 g/m2 in terms of dry weight.

The developer layer coating solution thus prepared can be coated on high-quality paper, coated paper, synthetic paper, and film using conventional coating equipment such as an air knife coater, a flade coater, a roll coater, a size press coater, a curtain coater, and a short dwell coater. It is coated on a support such as, and finished as a colored paper for pressure-sensitive copying paper.

Note that the method of the present invention can be applied to a self-coloring method having a color developer layer and a color former layer on the same side of the support, or a mixed coating layer of a color developer coating liquid and a coating liquid containing an encapsulated color former. Of course, it can also be applied to type pressure-sensitive copying paper (so-called self-content type).

3 4 "Example J" Examples and comparative examples are described below in order to further clarify the effects of the present invention, but the present invention is not limited to these. and "%" represent "parts by weight" and "% by weight", respectively, unless otherwise specified.

Example 1 2000 g of water and 400 g of zinc sulfate (heptahydrate) are placed in a stainless steel cylindrical container with an internal volume of 20000 m equipped with a stirrer and a thermometer, and dissolved.

To this, 8500 g of a 10.chi. aqueous solution of I.lium 3,5-di(.alpha.-methylbenzyl)salicylate was added while stirring the contents vigorously. Due to double decomposition, the inside of the container immediately becomes a thixotropic drawer liquid. Here, a copolymer of α-methylstyrene and styrene (copolymerization ratio;
40:60 mole percent, average molecular weight; approximately 1500)
800 g of a methyl isobutyl ketone solution containing 25 g of a mixture of 150 g of compound 1-], 1-1 (see Tables 1 and 2, mixing ratio 50:50) are added within a short time. The fluidity of the contents, which form a thixotropic drawer, gradually improves, making it easier to flow (when it becomes easy to flow, heat the container to bring the temperature of the contents to 75°C and let it stand. The oil phase will separate, so take out the entire oil layer,
This has an internal volume of 5000m I! , transfer to a hard glass beaker.

This was further added to 600 g of water, 2.5 g of sodium carbonate, polyvinyl alcohol (degree of saponification: 981, degree of polymerization approximately 170).
0) 500 g of 5'A aqueous solution and 60 g of 25χ aqueous solution of copolymer of ethyl acrylate and acrylamide (copolymerization ratio: 13:87 mol percent, degree of polymerization: approximately 400)
An oil-in-water emulsion is obtained by adding the following ingredients and emulsifying for 20 minutes at a rotation speed of 8,800 to 9,000 times per minute using a homomixer (Model 11 manufactured by Tokushu Kika Kogyo Co., Ltd.) at a temperature of 35°C to 40°C. is obtained. This has an internal volume of 10,100 O with a stirrer, thermometer and distillation port.
0! Transfer to a hard glass three-necked flask and add 11 ml of water.
After adding 00g, heat the flask to a boil while stirring the contents slowly. When about 640 g of methyl isobutyl ketone and about 640 g of water were taken out from the distillation port,
The contents become an emulsion containing almost no methyl isobutyl ketone and a total solid content of 39χ. The average particle diameter of the obtained developer-dispersed particles was 1.9μ.

The softening point of the dispersed phase is 75°C.

[Preparation of color developer coating liquid] 18 parts of the 39% color developer dispersion obtained by the treatment described in section 2,
93 parts of calcium carbonate and 100 parts of water were mixed and dispersed, and as a binder, 50 parts of a 10% polyvinyl alcohol aqueous solution and 50% carboxy-modified SBR latex (
A developer coating solution was prepared by mixing and dispersing 20 parts of SN-307 (manufactured by Sumitomo Naugatac).

[Manufacture of color developer paper for pressure-sensitive copying paper]

The above color developer coating liquid was applied to one side of a base paper of 40 g/n (dry weight: 5 g/rrr) and dried to obtain a color developer paper for pressure-sensitive copying paper.

Example 2 In Example 1, compound 1-2゜2-2 (see Tables 1 and 2) was used instead of compound -1,2-1 (see Tables 1 and 2). A color developer aqueous dispersion was prepared in the same manner as in Example 1 except for the following steps.

The average particle diameter of the obtained developer-dispersed particles was 2.0 μm.

Next, this aqueous dispersion was processed with a sand grinder (manufactured by Igarashi Kikai Co., Ltd., MODEL NO. 03G-8G) at a rate of 2 kg per minute to prepare a color developer dispersion with an average particle size of 1.9μ. A developer paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1.

Example 3 In Example 1, compound 1-1. ．． 2-1. (see Tables 1 and 2), compound 1-32-3 (1
A color developer aqueous dispersion was prepared in the same manner as in Example 1 except that the following was used (see Table 2).

The average particle diameter of the obtained developer-dispersed particles was 1.6 μm.

Thereafter, the diameter of a developer paper for pressure-sensitive copying paper was determined in the same manner as in Example 1.

Example 4 In Example 1, compound 1-1.2-1. (Table 1,
Compound 1-4゜2-4 (see Table 2)
A color developer aqueous dispersion was prepared in the same manner as in Example 1 except that the following was used (see Table 2).

7 8 The average particle diameter of the obtained developer-dispersed particles was 1.9μ.

Thereafter, the diameter of a developer paper for pressure-sensitive copying paper was determined in the same manner as in Example 1.

Example 5 Example 2 except that compound 1-5゜2-5 (see Tables 1 and 2) was used instead of compound i2,2-2 (see Tables 1 and 2). An aqueous developer dispersion was prepared in the same manner as in Example 2.

The average particle diameter of the obtained developer-dispersed particles was 1.7 μm.

Thereafter, the diameter of a developer paper for pressure-sensitive copying paper was determined in the same manner as in Example 2.

Example 6 200 g of zinc 3-isododecylsalicylate (softening point: 43°C) and 295 g of zinc 3,5-di(α-methylbenzyl)salicylate were mixed and dissolved in 400 g of toluene at 50°C to prepare a toluene solution. Add compound 1 to this toluene solution. Add and dissolve 13 g of the mixture of -1.2-1 (see Table 1 and Table 2, mixing ratio 50:50).

Separately, in a stainless steel beaker with an internal volume of 3000 rd, 600 g of water, 2.5 g of sodium carbonate, and a copolymer of ethyl acrylate and acrylamide (copolymerization ratio: 1
3 to 87 mole percent, degree of polymerization; approximately 400) 25
An oil-in-water type was obtained by adding 100 g of the 2 aqueous solution and performing an emulsification operation for 20 minutes at a homomixer (model gate, manufactured by Tokushu Kika Kogyo Co., Ltd.) at a rotation speed of 8,800 to 9,000 revolutions per minute at a temperature of 35°C to 40°C. An emulsion of . Transfer this to a hard glass pressure-controlled flask with an internal volume of 10,000 ml and equipped with a stirrer, a thermometer, and a distillation port, add 1,000 g of water, and heat the flask to boil while stirring the contents slowly. When about 320 g of toluene and about 340 g of water are taken out from the distillation port, the contents become an emulsion containing almost no toluene and a total solid content of 39χ. The average particle diameter of the obtained developer-dispersed particles was 2.
．． It was 1μ.

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

Comparative Example 1 9 0 In Example 1, Compounds 1-1, 2-1. (Table 1,
(see Table 2), the UV absorber 2-(3
,5-di-toptyl-2-hydroxyphenyl)benzo I lyazole (trade name TINUWIN 320CI
An aqueous developer dispersion was prepared in the same manner as in Example 1, except that 25 g of the developer (manufactured by B^-GETGY) was used.

The average particle diameter of the obtained developer-dispersed particles was 1.9μ.

Thereafter, a developing paper strip for pressure-sensitive copying paper was prepared in the same manner as in Example 1.

Comparative Example 2 In Example 1, Compound 1=il-1 (Table 1, Table 2
(see table) instead of the UV absorber 2 (35-dibutyl-2-hydroxyphenyl)-5 chlorohencitrial (trade name TlN0VIN 327CIB8-G).
An aqueous developer dispersion was prepared in the same manner as in Example 1, except that 25 g of the developer (manufactured by ErGY) was used.

The average particle diameter of the obtained developer-dispersed particles was 1.911.

Thereafter, a developing paper strip for pressure-sensitive copying paper was prepared in the same manner as in Example 1.

Comparative Example 3 In Example 2, instead of compound 1-2.2-2 (see Tables 1 and 2), 2-(3,5-di-t-butyl-4hydroxyhensyl)-2- n-butylmalonate bis(L2,2,6.6-bentamethyl-4-piperidyl)
(Product name TINUVIN 144, CIBA-G
An aqueous developer dispersion was prepared in the same manner as in Example 2, except that 50 g of the developer (manufactured by EIGY) was used.

The average particle diameter of the obtained color developer-dispersed particles was 3.2μ.

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

Comparative Example 4 Compound 1-1.1-1 (see Tables 1 and 2) in Example 1 was not dissolved in methylisobutylkene 1-1,
A color developer paper for pressure-sensitive copying paper was obtained in the same manner except that the mixture was dispersed in a 2% polyvinyl alcohol aqueous solution and ground and dispersed using a sand grinder, and then added to the developer dispersion.

1 2 The following quality evaluation tests were conducted on the nine types of color developer paper for pressure-sensitive copying paper thus obtained, and the results are shown in Table 3.

[Creating the top paper]

A capsule coating liquid prepared by dissolving crystal violet lactone in alkylated naphthalene and microencapsulating this oily liquid was coated on one side of high-quality paper with a dry weight of 4 g/
% and dried to obtain upper paper.

[Creating inner paper]

A capsule coating liquid similar to that of the "-paper" was applied to the base paper surface of the developer paper for pressure-sensitive copying paper so that the dry weight was 4 g/m, and dried to obtain an inner paper.

Inori Rinke Namiken 2 The developing paper and the top paper were left in an atmosphere at 5°C for 1.0 hour. Next, the coated sides of the colored paper and top paper were placed opposite each other and heated to 5°C.
The color was developed using a falling color tester (weight: 150 g, height: 20 c+n) in an atmosphere of 1, and the color density was measured 10 seconds after striking and 1 day later using a Machess foul densitometer.

Layer the test developer paper and top paper on the j-stitch so that the coated surfaces are facing each other, apply a load of 1.20 kg/cm2 to form a colored image, measure the color density with a Maches color densitometer, and check the color density. value D
o. Next, after irradiating sunlight for 1011 rs, the color density was measured and the value was expressed as:

Light resistance is defined by the following formula, and the closer the value is to 100, the better the light resistance.

1 Light resistance-×100 D.

3 4 Table 3 "Effects" As is clear from the results in Table 3, the developer paper for pressure-sensitive copying paper obtained in the example of the present invention was excellent in both initial color development and light fastness. It had certain characteristics.

Claims (3)

[Claims] (1) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼[I] [In formula [I], R_1, R_2, R_3, and R
_4 is a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group, a phenyl group, a nuclear-substituted phenyl group, an aralkyl group, or a nuclear-substituted aralkyl group, which may be the same or different. Also, two adjacent ones of R_1, R_2, R_3, and R_4 may be combined to form a ring. n is a number of 1 or more, M is magnesium, calcium, zinc, aluminum, iron,
Cobalt, nickel or their basic ions. ] A color developer mainly composed of a nuclear-substituted salicylate represented by the above and a compound represented by the general formula [II] and/or the general formula [III] are dissolved in an organic solvent, and this solution is dissolved in an aqueous medium. A method for producing an aqueous color developer dispersion obtained by emulsifying and dispersing the dispersion with or without heating, and then heating the dispersion to distill off the organic solvent. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [II] [In formula [II], R_5 is a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, a phenyl group, a nuclear-substituted phenyl group, Aralkyl group,
or a nuclear-substituted aralkyl group. R_6 is an alkyl group, an alkyl group having a substituent, a cycloalkyl group, an aryl group, a monoester residue of a diol having 12 or less carbon atoms, a monoester residue of polyethylene glycol which may have a substituent, a substituent. The monoester residue of polypropylene glycol which may have a substituent or the monoester residue of polybutylene glycol which may have a substituent is shown. ] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [III] [In the formula [III], R_7 is a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, a phenyl group, a nuclear-substituted phenyl group, Aralkyl group,
or represents a nuclear-substituted aralkyl group. R_8 is an alkylene group that may have a substituent, a diester residue of polyethylene glycol that may have a substituent, a diester residue of polypropylene glycol that may have a substituent, or a diester residue of polypropylene glycol that may have a substituent. Represents a diester residue of polybutylene glycol. ] (2) The volume average particle diameter of the color developer in the color developer aqueous dispersion is 5
A method for producing a color developer aqueous dispersion having a size of micron or less. (3) A pressure-sensitive copying paper obtained by coating a support with a coating liquid containing the aqueous developer dispersion according to claim (1) or (2).