JP3125342B2 - Developer composition dispersion and pressure-sensitive copy sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive copying sheet excellent in low-temperature initial color development obtained by applying a developer composition dispersion and a coating solution containing the dispersion.

[0002]

2. Description of the Related Art An electron-donating organic color former (e.g.,
(Hereinafter, simply referred to as a color former) A color paper capsule composition mainly composed of microcapsules containing an oily substance in which a dissolved substance is dissolved is coated on one surface of a support, and the above color former is contacted on one surface of the support. Electron-accepting color developer
(Hereinafter simply referred to as a developer) is applied with a developer composition as a main component, and only the developer composition is applied on one side of a medium paper and a support on which a color former capsule composition is applied on the other side. There are various sheets such as coated lower paper, generally upper paper-lower paper,
Alternatively, a combination of an upper sheet, a middle sheet, and a lower sheet is practically used as a copy set. In addition, a self-coloring type pressure-sensitive copying paper in which a color developing agent and a color developing agent are applied on the same surface of a support to enable pressure-sensitive copying with one sheet is also known as one form thereof.

[0003] Coloring agents for such pressure-sensitive copying paper include inorganic coloring agents such as acid clay, activated clay, attapulgite, zeolite, bentonite, silica, aluminum silicate, and the like, phenol-aldehyde polymers, phenol-acetylene. Organic colorants such as phenolic polymers such as polymers and polyvalent metal salts of aromatic carboxylic acids or derivatives thereof are known.

Of these, organic colorants such as a nuclear-substituted salicylate have a higher color-forming ability than inorganic colorants, and the resulting color image has a reduced density due to the adhesion of moisture or ordinary file storage. It has the advantage of not being. However, the color density immediately after printing is low, and there is a disadvantage that it takes time to reach the saturation density (a defect that is inferior to initial color development), and it takes time until a sufficient recording density is obtained, particularly in a low-temperature environment. Improvement of the initial coloring property has been desired.

Heretofore, as a method of solving such a drawback, a method of decreasing the viscosity of an oily substance in which the color former is dissolved to accelerate the contact between the color former and the color former has been performed. But,
Particularly under low-temperature conditions, the viscosity of the oily substance increases, so that satisfactory results have not been obtained by such a method.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a pressure-sensitive copying sheet having excellent low-temperature initial coloring properties.

[0007]

According to the present invention, there is provided a developer composition comprising a nucleus-substituted salicylate as a main component, which has a boiling point of 100.degree.
Organic solvent from 250 ° C to 150 ° C and boiling point from 250 ° C to 335 ° C
In a mixed solvent of a non-volatile oil, and this solution is emulsified and dispersed in an aqueous medium.
A developer composition dispersion obtained by removing an organic solvent at a temperature of from 00 ° C to 150 ° C by distillation.

[0008] The present invention also relates to the present invention,
Disclosed is the developer composition dispersion represented by the formula (1), wherein the volume average particle diameter of the developer composition in the developer composition dispersion is 4 μm or less.

[0009]

Embedded image

[However, R _1, R _2, R ₃ and R ₄ may be the same or different and each may be a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group, a phenyl group, a nucleus. substituted phenyl group, an aralkyl group or a nuclear substituted aralkyl group, and _{R 1, R 2, R 3} ,
And two of R ₄ and R ₄ may be combined to form a ring. n represents an integer of 1 or more, and M represents a monovalent or polyvalent metal atom. Further, the present invention discloses a pressure-sensitive copying sheet obtained by applying a coating solution containing the above-described developer composition dispersion to a support.

[0011]

In the present invention, the boiling point is from 100 ° C to 150 ° C.
The use of a mixed solvent of an organic solvent and a non-volatile oil having a boiling point of 250 ° C. to 335 ° C. is based on the following reasons. An organic solvent having a boiling point of from 100 ° C. to 150 ° C. has a high solubility of a color developer, is not only easy to remove by distillation, but is necessary for reducing the volume average particle diameter to 4 μm or less. As a result, the color developability is improved, and no stains are generated.

When an organic solvent having a boiling point of more than 150 ° C. is used, the volume average particle diameter after dispersion tends to be large, and when an organic solvent having a boiling point of less than 100 ° C. is used, the water dispersion system becomes unstable during removal by distillation. , And the aqueous medium and the oil layer are easily separated, and the desired aqueous dispersion cannot be produced. In addition, a non-volatile oil having a boiling point of from 250 ° C. to 335 ° C. is necessary for improving low-temperature initial color development. A non-volatile oil having a boiling point of less than 250 ° C. is inferior in the effect of improving the initial color development at a low temperature, and 335
When a non-volatile oil having a temperature of more than ° C is used, the aqueous dispersion becomes unstable at the time of removal by distillation, and aggregates are easily formed, so that the intended aqueous dispersion cannot be produced. That is, in the present invention, the boiling point is 1
Organic solvent of 00 to 150 ° C and boiling point of 250 to 3
The use of a mixed solvent of a non-volatile oil at 35 ° C. makes good use of the properties described above.

Among the nuclear-substituted salicylates, [Chemical Formula 1]
Each of the nuclear-substituted salicylates represented by the formula (1) has excellent color developing ability. Typical examples thereof include 3-methyl-5-isononyl salicylic acid, 3-methyl-5-isododecyl salicylic acid, 3-methyl-5-isopentadecyl salicylic acid, and 3-methyl-5- (α-methylbenzyl). ) Salicylic acid, 3-methyl-5- (α, α-dimethylbenzyl) salicylic acid, 3,5-disiarybutylbutylsalicylic acid,
3,5-di-tert-butyl salicylic acid, 3,5-di-tert-butyl-6-methyl salicylic acid, 3-tert-butyl-5-phenyl salicylic acid, 3,5-di-tert-amyl salicylic acid, 3-tert-octyl-6-yl
Methyl salicylic acid, 3-cyclohexyl-5-isononyl salicylic acid, 3-phenyl-5-isononyl salicylic acid, 3- (α-methylbenzyl) -5-isononyl salicylic acid, 3-isopropyl-5-isononyl salicylic acid, 3- Isononyl salicylic acid, 3-isononyl-5-
Methyl salicylic acid, 3-isononyl-5-tert-butylsalicylic 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-tert-butyl-5-isononylsalicylic acid, 3,5-diisononylsalicylic acid, 3-isododecylsalicylic acid, 3-isododecyl-5-methylsalicylic acid, 3-isododecyl-6 Methyl salicylic acid, 3-isopropyl-5-isododesi Salicylic acid, 3-isododecyl-5-ethylsalicylic acid, 5-isododecylsalicylic acid, 3-isopentadecylsalicylic acid, 3-isopentadecyl-5-methylsalicylic acid, 3-isopentadecyl-6-methylsalicylic acid, 5-isopentane Decylsalicylic 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,
3,5-di-tert-butylsalicylic 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-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-
And polyvalent metal salts such as (α, α-dimethylbenzyl) -2-naphthoic acid. Specific examples of polyvalent metal salts include magnesium, calcium, zinc, aluminum,
Iron, cobalt, nickel and the like can be mentioned, but zinc is most preferable. These may be used alone or as a mixture. Here, an isononyl group, an isododecyl group, and an isopentadecyl group are defined as a general term for the substituents formed by the addition of propylene trimer, propylene tetramer or 1-butene trimer and propylene pentamer, respectively.

Some of these substituted salicylates are crystalline alone, and their softening points also vary. In order to prepare a non-crystalline developer composition having a preferable softening point, the developer composition is appropriately mixed and adjusted to obtain desired physical properties. If the softening point of the developer is too low, the developer applied and dried on the paper surface penetrates and transfers between the paper fibers to lower the color density, and the aqueous dispersion of the developer is also easily coagulated, and the It may lack storage stability over time.

On the other hand, if the softening point of the color developer is extremely high, it is difficult for the developer to exhibit self-adhesion when coated and dried on the paper surface, and a large amount of adhesive must be used in order to fix it to the paper surface. However, in this case, the adhesive may act as a film to hinder the transfer of the dye-dissolving oil present in the microcapsules, and the color developing ability may be slightly inferior. For these reasons, the softening point range of the developer is preferably 20 ° C. or higher, more preferably about 30 ° C. to 85 ° C.

As a method of adjusting the softening point of the developer to a preferable temperature, first, a developer having a different softening point is mixed, and second, a method of lowering the softening point of the developer is as follows. The addition of a substance that lowers the softening point, such as a metal salt of a fatty acid, a trialkylphenol, a trialkylalkylphenol or a styrene oligomer, and thirdly, a substance that increases the softening point of a developer having a softening point that is too low. For example, addition of polystyrene, poly-α-methylstyrene or petroleum resin can be mentioned. The mixing ratio is not particularly limited.

The term "softening point" as used in the present invention means a softening temperature in a state where a color developer contains equilibrium moisture in water. Usually, it is about 50 ° C. lower than the softening point in a dry state. In addition, a resin such as a copolymer of α-methylstyrene and styrene, an ultraviolet absorber, other auxiliaries, and the like can be appropriately added to the developer composition. The boiling point used in the present invention is from 100 ° C. to 15
As organic solvents at 0 ° C., nitromethane, dioxane,
Toluene, nitroethane, pyridine, methyl isobutyl ketone, ethylenediamine, 1-butanol, acetic acid,
-Methoxyethanol, octane, butyl acetate, morpholine, chlorobenzene, 2-ethoxyethanol, xylene (such as o-xylene, m-xylene, p-xylene and mixtures thereof), acetic anhydride and the like.

These organic solvents may be used alone or in combination of two or more. Boiling point is 25
Examples of the non-volatile oil at 0 ° C. to 335 ° C. include alkylnaphthalenes, diarylalkanes, alkylbenzenes, alkylbiphenyls, hydrogenated terphenyls and derivatives thereof, and chlorinated paraffins. Specifically, monoisopropylnaphthalene, diisopropylnaphthalene, 1-isopropylphenyl-2-phenylethane, 1-isopropylphenyl-1-phenylethane, 1,1-ditolylethane, 1-ethylphenyl-1
-Phenylethane, 1-phenyl-1-xylylethane, cyclohexylbenzene, bicyclohexylbenzene, 2-methylbiphenyl, 3-methylbiphenyl, 3,3-dimethylbiphenyl, 2,4-dimethylbiphenyl, 2,6-dimethylbiphenyl, 2,
4,6-trimethyl biphenyl, monoisopropyl biphenyl and the like are exemplified. These non-volatile oils may be used alone or in combination of two or more.

The mixing ratio of the organic solvent having a boiling point of 100 to 150 ° C. and the non-volatile oil having a boiling point of 250 to 335 ° C. is not particularly limited. It is about 10 to 1000 parts by weight, preferably about 10 to 100 parts by weight, of a non-volatile oil having a temperature of about 335 ° C. Although not particularly limited, the developer composition 10
Usually, about 50 parts by weight or more of the mixed solvent is used with respect to 0 parts by weight, and preferably about 70 to 400 parts by weight.

In order to emulsify and disperse the developer composition produced by the above method in an aqueous medium, examples of the dispersing agent to be contained in the aqueous medium include alkali salts of alkyl sulfates and alkali salts of alkylbenzene sulfonic acids. Alkyl naphthalene sulfonic acid alkali salts, oleic acid amide sulfonic acid alkali salts, dialkyl sulfosuccinic acid alkali salts and other anionic surfactants, polyoxyethylene alkyl ethers, nonionic surfactants such as polyoxyethylene fatty acid esters, Natural polymer substances such as gum arabic, sodium alginate, agar, gelatin, etc., semi-synthetic polymer substances such as carboxymethyl cellulose, hydroxyethyl cellulose, carboxymethylated starch, phosphorylated starch, sodium lignin sulfonate, methyl vinyl ether・ Maleic anhydride copolymer, ethylene / maleic anhydride copolymer, styrene / maleic anhydride copolymer, acrylic acid polymer, acrylic acid / methyl methacrylate copolymer, acrylic acid / acrylamide copolymer, vinyl Alkaline salts of polymers and copolymers such as benzenesulfonic acid polymers, polyvinyl alcohol, polyacrylamide, and synthetic high molecular substances such as vinyl carboxylic acid ester / acrylamide copolymers, etc. Among them, a vinyl carboxylate / acrylamide copolymer is particularly preferred. Polymerization degree is 1
00 or more and at least acrylamide 70 to 96
Acrylamide copolymers having a mole ratio of 4 to 30 mole% of an alkyl or alkoxyalkyl ester of acrylic acid, methacrylic acid, itaconic acid or maleic acid having 4 or less carbon atoms have a large protective colloid property, It is particularly preferable because of low foaming property.

The amount of the dispersant used is appropriately adjusted depending on the size of the target dispersed particles, but is preferably adjusted at a ratio of about 1 to 30 parts by weight based on 100 parts by weight of the developer. You. These dispersants may be used alone or in combination of two or more. The emulsification and dispersion may be carried out with heating or without heating.

The aqueous dispersion of the developer composition thus prepared is heated, reduced in pressure and the like to a boiling point of 100 to 150.
The organic solvent at ℃ is distilled off to prepare a developer composition aqueous dispersion. If the organic solvent having a boiling point of 100 to 150 ° C. is not removed, the organic solvent evaporates in the step of coating on the support. Therefore, a coating machine having equipment for the organic solvent must be used. The pressure-sensitive copying sheet has a boiling point of 100 to 150.
When the organic solvent at a temperature of ° C. remains, there is a problem of odor, particularly when a printing machine for fixing the toner by heat is used, and a bad smell is generated.

The aqueous dispersion of the developer composition thus obtained can be further subjected to a dispersion treatment. Examples of the disperser include various types of sand mill type pulverizers using a pulverizing medium such as a ball mill, a pebble mill, a sand grinder (vertical type, horizontal type), a cobol mill, an attritor, a dyno mill, a three-roll mill, a high-speed impeller disperser, and a high-speed stone. High-speed grinding equipment such as a mill and a high-speed impact mill can be mentioned, but in consideration of ease of setting processing conditions, crushing efficiency, etc., a sand mill type (vertical type, horizontal type) and a high-speed impeller disperser are preferable. Sand mill type pulverizers (vertical type, horizontal type) are more preferable.

Generally, the concentration of the developer composition in the aqueous dispersion is usually as high as 10% or more, and the preferred upper limit is 55%.
It is about. Such a high concentration not only reduces the transportation cost, but also makes it possible to prepare a high-concentration coating liquid, thereby increasing the drying efficiency in the coating process and improving the quality of the obtained color paper for pressure-sensitive copying paper. Can also be expected. In the coating solution for forming the color developer layer, the color developer composition dispersion thus obtained is usually further used as an adhesive, for example, starch, casein, gum arabic, carboxymethyl cellulose,
Polyvinyl alcohol, styrene / butadiene copolymer latex, vinyl acetate latex, and the like are blended.
Further, inorganic pigments such as zinc oxide, magnesium oxide, titanium oxide, aluminum hydroxide, calcium carbonate, magnesium sulfate, and calcium sulfate, and various auxiliaries known in the field of pressure-sensitive copying paper can be appropriately added.

The amount of the developer layer coating liquid applied to the support is not particularly limited, but is about ² to 8 g / m ² in terms of dry weight. The thus-prepared coating solution for the developer layer is applied to a high quality paper, a coated paper, a synthetic paper, a film by a usual coating apparatus such as an air knife coater, a blade coater, a roll coater, a size press coater, a curtain coater, a short dwell coater, and the like. Etc., and finished as a pressure-sensitive copying sheet.

The method of the present invention comprises a step of providing a developer layer and a color former layer on the same surface of a support or a mixed coating layer of a developer coating liquid and a coating liquid containing an encapsulated color former. Of course, the present invention can also be applied to a self-coloring type pressure-sensitive copying paper (so-called self-contained type).

[0027]

EXAMPLES Examples and comparative examples are described below to further clarify the effects of the present invention, but the present invention is not limited to these examples. In the examples, "parts" 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) were placed in a 20,000 ml stainless steel cylindrical vessel equipped with a stirrer and a thermometer and dissolved therein. The 3,5-di (α
-Methylbenzyl) 10% aqueous solution of sodium salicylate 85
00g, copolymer of α-methylstyrene and styrene (copolymerization ratio: 40 to 60 mole percent, average molecular weight: about 1500) 15
0 g, 800 g of methyl isobutyl ketone (boiling point: 116 ° C.) and 200 g of diisopropylnaphthalene (boiling point: 305 ° C.) are added in a short time while vigorously stirring the contents. Since the fluidity of the thixotropic-dropped contents gradually improves, when the contents easily flow, the container is heated to a temperature of 75 ° C. and allowed to stand. The aqueous phase is separated into the upper layer and the oil phase is separated into the lower layer.
Transfer to 5000ml hard glass beaker. This is further mixed with 600 g of water, 2.5 g of sodium carbonate, 500 g of a 5% aqueous solution of polyvinyl alcohol (degree of saponification: 98%, polymerization degree: about 1700) and a copolymer of ethyl acrylate and acrylamide (copolymerization ratio: 13 to 87 mol). Percent, degree of polymerization; about 400) Add 60 g of 25% aqueous solution, and homomixer (Model M, manufactured by Tokushu Kika Kogyo Co., Ltd.) at 8800 min.
An oil-in-water emulsion is obtained by performing the emulsification operation at 9000 rotations for 20 minutes. This is transferred to a 10,000 ml hard glass three-necked flask equipped with a stirrer, a thermometer, and a distillation port, and 2,000 g of water is further added. The flask is heated and boiled while slowly stirring the contents. When methyl isobutyl ketone and a part of water are taken out from the distillation port, the content becomes an emulsion having a total solid content of 38% without methyl isobutyl ketone. The average particle diameter of the obtained developer composition dispersed particles was 1.2 μm.

[Preparation of developer coating solution] 27 parts of the 38% developer composition dispersion liquid obtained by the above treatment, calcium carbonate 90
And 100 parts of water, mixed and dispersed.
A 50% aqueous solution of polyvinyl alcohol and 10 parts of 50% carboxy-modified SBR latex (SN-307, manufactured by Sumitomo Nogatack Co., Ltd.) were mixed and dispersed to prepare a developer coating solution.

[0030] applying the [pressure-sensitive copying paper for developing the production of colored paper] the color developer coating solution so that the dry weight on one side of the base paper 40 g / m ² is 4g / m ^2, and dried to pressure-sensitive copying paper A color developing paper was obtained.

Example 2 In Example 1, toluene (boiling point: 111) was used in place of methyl isobutyl ketone and diisopropyl naphthalene.
℃) and 800 g of 1-isopropylphenyl-2-phenylethane (boiling point 315 ° C) in the same manner as in Example 1 to prepare a toluene-free developer composition aqueous dispersion. The average particle diameter of the obtained developer composition dispersed particles is
2.0 μ (38% total solids). Thereafter, a color-developed paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1.

Example 3 2000 g of water and 400 g of zinc sulfate (heptahydrate) were placed in a 20,000 ml stainless steel cylindrical vessel equipped with a stirrer and a thermometer and dissolved therein. To this, 6000 g of a 10% aqueous solution of sodium 3-isononyl salicylate, 2500 g of a 10% aqueous solution of sodium 3,5-di (α-methylbenzyl) salicylate, a copolymer of α-methylstyrene and styrene (copolymerization ratio: 40 to 60 mol) Percent, average molecular weight; about 15
00) 150 g, 400 g of p-xylene (boiling point 139 ° C.) and 600 g of 1-phenyl-1-xylylethane (boiling point 296 ° C.) are added in a short period of time with vigorous stirring of the contents. Since the fluidity of the thixotropic-dropped contents gradually improves, when the contents easily flow, the container is heated to a temperature of 75 ° C. and allowed to stand. The aqueous phase is separated into the upper layer and the oil phase is separated into the lower layer.
Transfer to a 00 ml hard glass beaker. This further
600 g of water, 2.5 g of sodium carbonate, 500 g of a 5% aqueous solution of polyvinyl alcohol (degree of saponification: 98%, degree of polymerization: about 1700) and a copolymer of ethyl acrylate and acrylamide (copolymerization ratio: 13 to 87 mol%, degree of polymerization Approx. 400) Add 60g of 25% aqueous solution, and homogenize (Model M, manufactured by Tokushu Kika Kogyo Co., Ltd.) at 8800 min./min.
An oil-in-water emulsion is obtained by performing the emulsification operation at 9000 rotations for 20 minutes. Transfer this to a 10,000 ml hard glass three-necked flask equipped with a stirrer, thermometer and distillation port, add 2000 g of water, and heat the flask while slowly stirring the contents. When p-xylene and a part of water are removed, the content becomes an emulsion having a total solid content of 38% without p-xylene.
The average particle size of the obtained developer-dispersed particles was 0.9 μm.

Comparative Example 1 In Example 1, 1000 g of methyl isobutyl ketone was used for emulsification and dispersion in the same manner without using diisopropylnaphthalene as a solvent, and methyl isobutyl ketone was distilled to prepare a developer aqueous dispersion. The average particle size of the obtained developer-dispersed particles was 1.2 μm (total solid content: 38%). Thereafter, a color developing paper for pressure-sensitive copying paper was obtained in the same manner.

Comparative Example 2 In Example 1, 1000 g of diisopropylnaphthalene was emulsified and dispersed in the same manner as in Example 1 except that methyl isobutyl ketone was not used as a solvent, and an aqueous developer dispersion was prepared without distillation. The average particle diameter of the obtained developer-dispersed particles was 6 μ (total solid content: 38%). Thereafter, a color developing paper for pressure-sensitive copying paper was obtained in the same manner. Comparative Example 3 A developing paper for pressure-sensitive copying paper was obtained in the same manner as in Example 1, except that methyl isobutyl ketone was not removed by distillation after emulsification and dispersion.

The following color evaluation tests were carried out on the thus obtained color-developed papers for pressure-sensitive copying paper, and the results are shown in Table 1.

[Preparation of Top Paper] Crystal violet lactone is dissolved in alkylated naphthalene, and this oily liquid is microencapsulated. The capsule coating liquid is prepared so that the dry weight is 4 g / m ^{2 on} one side of high quality paper. Coating and drying yielded upper paper.

[Low Temperature Initial Color Development Test] The color-developed paper and the upper paper were left in an atmosphere of 0 ° C. for 10 hours. Next, the coated surfaces of the colored paper and the upper paper are opposed to each other, and the color is formed by a drop-type color tester (weight: 150 g, height: 15 cm) in an atmosphere of 0 ° C.
The color density was measured 10 seconds after the pressing with a Macbeth reflection densitometer. [Coloring density] The above coloring test sample was left at room temperature for 3 days, and the coloring density was measured with a Macbeth densitometer. [Cosmetic stain resistance test] The developed paper and the upper paper are overlapped so that the coated surfaces face each other, and rubbed 5 times under a load of 5 kg / cm ² to determine the degree of color stain on the coated surface of the developed paper. The results are shown in Table 1.

；: Almost no contamination ×: Dirt is conspicuous and poses a problem in practical use XX;

[0039]

[Table 1]

[0040]

As is clear from the results shown in Table 1, the pressure-sensitive copying sheet of the present invention is excellent in low-temperature initial coloring property and coloring property,
It was a pressure-sensitive copy sheet free from scratches.

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41M 5/124-5/165

Claims (3)

(57) [Claims] 1. A developer composition comprising a nucleus-substituted salicylate as a main component is dissolved in a mixed solvent of an organic solvent having a boiling point of 100 ° C. to 150 ° C. and a non-volatile oil having a boiling point of 250 ° C. to 335 ° C. A developer composition dispersion obtained by emulsifying and dispersing this solution in an aqueous medium and subsequently distilling off an organic solvent having a boiling point of 100 ° C. to 150 ° C. from the dispersion. 2. The developer according to claim 1, wherein the nucleus-substituted salicylate is represented by the following chemical formula (1), and the developer composition in the developer composition dispersion has a volume average particle diameter of 4 μm or less. Composition dispersion. Embedded image [However, R _1, R _2, R ₃ and R ₄ may be the same or different and may be a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group, a phenyl group, It is a phenyl group, an aralkyl group, or a nucleus-substituted aralkyl group, and _two adjacent groups out of R _1, R _2, R _3, and R ₄ may combine to form a ring. n represents an integer of 1 or more, and M represents a monovalent or polyvalent metal atom. ] 3. A pressure-sensitive copying sheet obtained by applying a coating solution containing the developer composition dispersion according to claim 1 to a support.