JP3320528B2 - Developer composition and pressure-sensitive recording 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 developer composition and a pressure-sensitive recording sheet obtained by applying the composition to a support.

[0002]

2. Description of the Related Art Conventionally, pressure-sensitive recording sheets, for example,
An upper sheet coated on one side of a support with a microcapsule composition containing, as a main component, a capsule containing an oily substance in which an electron donating color forming compound or the like is dissolved, and the above electron donating color forming compound on one side of the support. An intermediate sheet coated with a developer composition mainly composed of an electron-accepting developer that exhibits a color when it comes into contact with the microcapsule composition on the opposite surface, and the above-mentioned on one surface of a support. There is a lower sheet coated with a developer composition, and is generally used in a combination of an upper sheet-lower sheet or an upper sheet-middle sheet-lower sheet. There is also a single copy sheet in which the microcapsule composition and the electron-accepting developer composition are coated on the same side of a support so that copying can be performed with one sheet.

[0003] Conventionally, salicylic acid derivatives, for example,
A polyvalent metal salt of a 3,5-disubstituted salicylic acid derivative (for example, JP-B-51-25174) or a reaction of salicylic esters with styrenes to hydrolyze the resulting salicylic acid ester resin, It is known that a polyvalent metal salt of a salicylic acid resin obtained by reacting a valent metal compound (JP-A-1-133780) is useful as an electron-accepting developer for a pressure-sensitive recording sheet. However, a pressure-sensitive recording sheet using a polyvalent metal salt of these salicylic acid derivatives as an electron-accepting color developer has a coloring speed,
In particular, the color developing speed in a low-temperature environment is low, and it takes a long time to obtain an image having a sufficient color density for practical use. At present, a pressure-sensitive recording sheet having a high coloring speed is desired.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a developer composition having an excellent color-forming speed, and a pressure-sensitive recording sheet formed by applying the composition.

[0005]

Means for Solving the Problems In order to meet the above-mentioned demands, the present inventors have conducted intensive studies on a color developer composition and a pressure-sensitive recording sheet, and have reached the present invention. That is, the present invention relates to a developer containing a polyvalent metal salt of a salicylic acid derivative as a component, and a developer composition containing glycerol. Further, the present invention relates to a pressure-sensitive recording sheet obtained by applying the above-described developer composition to a support. As the polyvalent metal salt of the salicylic acid derivative according to the present invention, preferably, for example, a polyvalent metal salt of a salicylic acid derivative represented by the general formula (1) (Formula 1) can be mentioned.

[0006]

Embedded image (Wherein, R _{1 to} R ₄ represent a hydrogen atom, an alkyl group, an alkoxy group, an aralkyl group, an aryl group, or a halogen atom, and two adjacent groups among R _{1 to} R ₄ are bonded to each other to form a ring. May be formed)

In the general formula (1), R _{1 to} R ₄ each represent a hydrogen atom, an alkyl group, an alkoxy group, an aralkyl group, an aryl group or a halogen atom;
Of ₁ to R _4, they may form a ring by bonding two groups adjacent. Preferably, it may have a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms which may have a substituent, or a substituent. An aryl group having 6 to 20 carbon atoms, a fluorine atom, a chlorine atom, and a bromine atom.

Specific examples of the polyvalent metal salt of the salicylic acid derivative according to the present invention include, for example, salicylic acid, 3-methylsalicylic acid, 6-ethylsalicylic acid, 5-isopropylsalicylic acid, 5-sec-butylsalicylic acid, 5-tert-
Butylsalicylic acid, 5-tert-amylsalicylic acid, 5-
Cyclohexyl salicylic acid, 5-n-octyl salicylic acid, 5-tert-octyl salicylic acid, 5-isononyl salicylic acid, 3-isododecyl salicylic acid, 5-isododecyl salicylic acid, 5-isopentadecyl salicylic acid, 4
-Methoxysalicylic acid, 6-methoxysalicylic acid, 5-
Ethoxysalicylic acid, 6-isopropoxysalicylic acid,
4-n-hexyloxysalicylic acid, 4-n-decyloxysalicylic acid, 3,5-di-tert-butylsalicylic acid, 3,5-di-tert-octylsalicylic acid, 3,5-
Diisononyl salicylic acid, 3,5-diisododecyl salicylic acid, 3-methyl-5-tert-nonyl salicylic acid, 3
-Tert-butyl-5-isononylsalicylic acid, 3-isononyl-5-tert-butylsalicylic acid, 3-isododecyl-5-tert-butylsalicylic acid, 3-isononyl-5
-Tert-amylsalicylic acid, 3-isononyl-5-tert
-Octylsalicylic acid, 3-isononyl-6-methylsalicylic acid, 3-isododecyl-6-methylsalicylic acid,
3-sec-octyl-5-methylsalicylic acid, 3-isononyl-5-phenylsalicylic acid, 3-phenyl-5-
Isononyl salicylic acid, 3-methyl-5- (α-methylbenzyl) salicylic acid, 3-methyl-5- (α, α-dimethylbenzyl) salicylic acid, 3-isononyl-5-
(Α-methylbenzyl) salicylic acid,

3- (α-methylbenzyl) -5-tert-
Butylsalicylic acid, 3-benzylsalicylic acid, 5-benzylsalicylic acid, 3- (α-methylbenzyl) salicylic acid, 5- (α-methylbenzyl) salicylic acid, 3-
(Α, α-dimethylbenzyl) salicylic acid, 4- (α,
α-dimethylbenzyl) salicylic acid, 5- (α, α-dimethylbenzyl) salicylic acid, 3,5-di (α-methylbenzyl) salicylic acid, 3,5-di (α, α-dimethylbenzyl) salicylic acid, 3- ( α-methylbenzyl)-
5- (α, α-dimethylbenzyl) salicylic acid, 3-
(1 ′, 3′-diphenylbutyl) salicylic acid, 5-
(1 ′, 3′-diphenylbutyl) salicylic acid, 3-
[Α-methyl-4 ′-(α′-methylbenzyl) benzyl] salicylic acid, 5- [α-methyl-4 ′-(α′-methylbenzyl) benzyl] salicylic acid, 3- (α-methylbenzyl) -5 -(1 ', 3'-diphenylbutyl)
Salicylic acid, 3- (1 ', 3'-diphenylbutyl)-
5- (α-methylbenzyl) salicylic acid, 3-phenylsalicylic acid, 5-phenylsalicylic acid, 3- (α-methylbenzyl) -5-phenylsalicylic acid, 3- (α, α
-Dimethylbenzyl) -5-phenylsalicylic acid, 3-
Phenyl-5- (α-methylbenzyl) salicylic acid, 5
-(4'-methylphenyl) salicylic acid, 5- (4'-
Methoxyphenyl) salicylic acid, 5-fluorosalicylic acid, 3-chlorosalicylic acid, 4-chlorosalicylic acid, 5
-Chlorosalicylic acid, 5-bromosalicylic acid, 3-chloro-5- (α-methylbenzyl) salicylic acid, 3- (α
-Methylbenzyl) -5-chlorosalicylic acid, 2-hydroxy-1-benzyl-3-naphthoic acid, 2-hydroxy-3- (α, α-dimethylbenzyl) -1-naphthoic acid, 3-hydroxy-7- ( α, α-dimethylbenzyl) -2-naphthoic acid,

Further, for example, Japanese Patent Application Laid-Open No. 62-1948
6, carboxy-modified terpene phenol resin described in JP-A-63-112537 and JP-A-63-1
JP-A-86729 and JP-A-1-133780, and the like.
And polyvalent metal salts such as polybenzylated styrenated salicylic acid resin derivatives described in JP-A-160815 and the like. Specific examples of the polyvalent metal include, for example, magnesium, zinc, nickel, aluminum, and calcium, and zinc is particularly preferable. These salicylic acid derivative polyvalent metal salts may be used alone or in combination of two or more. Furthermore, a polyvalent metal salt of a mixed salicylic acid derivative obtained by using a plurality of types of salicylic acid derivatives to obtain a polyvalent metal salt may be used. In the salicylic acid derivative, an isononyl group, an isododecyl group, and an isopentadecyl group are
Propylene trimer, propylene tetramer or 1 respectively
-A general term for substituents formed by the addition of butene trimer and propylene pentamer. Some of the above salicylic acid derivatives are commercially available, and can also be obtained, for example, from a phenol derivative by a Kolbe-Schmidt reaction.

The method for producing the polyvalent metal salt of the salicylic acid derivative according to the present invention is not particularly limited.
Known methods can be applied. For example, one or more salicylic acid derivatives and polyvalent metal compounds (eg, oxides, hydroxides, carbonates, silicates, organic carboxylate salts of polyvalent metals)
(Melting method) or a water-soluble salt of a salicylic acid derivative such as an alkali metal salt, an amine salt or an ammonium salt of one or more salicylic acid derivatives, and a water-soluble polyvalent metal compound (for example, , Sulfates such as zinc sulfate, magnesium sulfate, calcium sulfate, and aluminum sulfate, chlorides such as zinc chloride, magnesium chloride, calcium chloride, nickel chloride, and aluminum chloride, and acetates such as zinc acetate) in the presence of water. A method of producing by acting (double decomposition method) can be applied.

The color developer composition of the present invention is a color developer containing a polyvalent metal salt of a salicylic acid derivative and a color developer composition containing glycerol. The composition is not particularly limited. Glycerol is usually 0.5 to 20 parts by weight based on 100 parts by weight of a polyvalent metal salt of a salicylic acid derivative.
It is about 1 part by weight, more preferably about 1 to 10 parts by weight. In addition, in addition to glycerol, the developer composition of the present invention may further contain an oligomer of a styrene derivative, preferably an oligomer of about a dimer to a 20-mer of the styrene derivative, in a low-temperature environment. This is preferable in order to obtain a developer composition in which the color development speed is further improved. The oligomer may be a chain oligomer (for example, 1,3-diphenyl-1-butene which is a chain dimer of styrene) or a cyclic oligomer (for example, 1-methyl which is a cyclic dimer of styrene). -3-phenylindane)
Or a mixture thereof. In this case, the amount of the oligomer of the styrene derivative is preferably adjusted to about 1000 parts by weight or less, more preferably about 800 parts by weight or less, based on 100 parts by weight of glycerol.

As a method for preparing the color developer composition of the present invention, for example, a method of dispersing a polyvalent metal salt of a salicylic acid derivative and glycerol together or a method of separately dispersing and then mixing. Applicable. The dispersion treatment is usually performed in an aqueous medium, and the developer composition can be obtained as an aqueous dispersion. Usually, the developer composition is subjected to dispersion treatment to an average particle diameter of 3 μm or less, preferably 2 μm or less. As a method of obtaining an aqueous dispersion, for example, a polyvalent metal salt of a salicylic acid derivative and glycerol, in an aqueous medium, as a disperser, for example, a ball mill,
A method of obtaining an aqueous dispersion by pulverizing and dispersing using an attritor, a sand grinder, a pebble mill, a cobol mill, a dyno mill, a high-speed impeller disperser, a high-speed stone mill, etc. After dissolving in an aqueous medium, a method of emulsifying and dispersing in an aqueous medium using, for example, an ultrasonic disperser, a homogenizer, a homomixer, or the like, and removing an organic solvent to obtain an aqueous dispersion can be used. As the organic solvent used in the above method, those having low solubility in water, excellent solubility of the color developer, and having a relatively low boiling point are preferable.

Examples of such an organic solvent include hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene and 1-methylnaphthalene, dichloromethane, chloroform, tetrachloroethylene, 1,2-dichloroethane, 1,1,1- Trichloroethane, 1,
1,2-trichloroethane, 1,1,2,2-tetrachloroethane, chlorobenzene, o-dichlorobenzene,
Halogenated hydrocarbon solvents such as m-dichlorobenzene, p-dichlorobenzene, o-chlorotoluene, m-chlorotoluene, p-chlorotoluene, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ethyl acetate, acetic acid Examples thereof include ester solvents such as butyl and amyl acetate, and alcohol solvents such as butanol, pentanol, hexanol and cyclohexanol. These organic solvents can be used alone or in combination.

The amount of the organic solvent to be used is not particularly limited, but is usually 100% of the salicylic acid derivative polyvalent metal salt.
The amount is about 5 to 500 parts by weight, more preferably about 20 to 300 parts by weight, based on parts by weight. In this case, the emulsification and dispersion treatment is performed at a temperature equal to or lower than the boiling point of the organic solvent,
It is carried out under atmospheric pressure or under pressure. After the dispersion treatment, the organic solvent is distilled off to obtain an aqueous dispersion of the developer composition. As a method for distilling off the organic solvent, the organic solvent can be distilled off by heating the organic solvent to a temperature higher than the boiling point of the organic solvent under atmospheric pressure or reduced pressure. The aqueous dispersion of the developer composition thus obtained can be further subjected to a dispersion treatment using the above-described dispersing machine (for example, a sand grinder), if desired.

As a dispersant used for dispersing in an aqueous medium, an ionic or nonionic surfactant is preferable. As the dispersant, for example, polyvinyl alcohol,
Alkyl-modified polyvinyl alcohol, cyanoethyl-modified polyvinyl alcohol, ether-modified polyvinyl alcohol, polyacrylamide, polyacrylic acid, acrylamide / alkyl acrylate copolymer, alkali metal salt of polystyrene sulfonic acid, maleic anhydride / isobutylene copolymer, carboxymethyl cellulose, Hydroxyethyl cellulose, polyvinylpyrrolidone, starch and derivatives thereof, casein, acacia, agar, synthetic or natural polymer compounds such as gelatin, alkali metal salts of alkylbenzenesulfonic acid, alkali metal salts of alkylnaphthalenesulfonic acid, dialkylsulfosuccinic acid Alkali metal salts, alkylsulfonic acid alkali metal salts, polyoxyethylene alkyl ethers, polyoxy Chi alkylphenyl ethers, polyhydric alcohol fatty acid esters.
In addition, these dispersants can be used alone or in combination. The amount of the dispersant used is not particularly limited, but is usually 100% of the polyvalent metal salt of the salicylic acid derivative.
It is about 1 to 30 parts by weight with respect to parts by weight. The amount of water used in preparing the aqueous dispersion is not particularly limited, but generally, the concentration of the developer composition in the aqueous dispersion is preferably 3 in consideration of handleability and the like. It is preferable to use an amount of about 50% by weight, more preferably about 5% to 40% by weight.

In the coating liquid for forming the color developer layer, a binder, a pigment and the like are usually added to the aqueous dispersion of the color developer composition obtained as described above. Examples of the binder include, but are not particularly limited to, polyvinyl alcohol, casein, starch and derivatives thereof, gum arabic, methylcellulose, carboxymethylcellulose, polyacrylic acid, styrene / butadiene copolymer latex, acrylate latex And synthetic or natural polymer compounds such as latexes. As the pigment, for example, zinc oxide, zinc carbonate, calcium carbonate, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, titanium oxide, talc, kaolin, activated clay, diatomaceous earth, aluminum hydroxide, magnesium hydroxide, alumina, Silica can be mentioned. Further, the coating solution for the developer layer includes:
If desired, various additives (for example, an ultraviolet absorber, an antifoaming agent, a pH adjuster, a viscosity adjuster, a plasticizer, an organic polymer compound, etc.) may be added.

The coating solution for the color developer layer thus prepared is supported by a known method, for example, by a coating device such as an air knife coater, a blade coater, a roll coater, a size press coater, and a curtain coater. A pressure-sensitive recording sheet can be prepared by applying the composition on a body (for example, paper, a plastic sheet, a synthetic paper, or a composite sheet obtained by combining them) to form a color developer layer. The weight of the developer layer on the support (that is, the amount of coating) is not particularly limited, but is usually 0.5% by dry weight.
g / m ² or more, preferably a 0.5 to 10 g / m ^2.

The form of the pressure-sensitive recording sheet of the present invention includes
Although not particularly limited, for example, a lower sheet used in combination with an upper sheet obtained by applying a microcapsule containing an electron-donating color-forming compound and capsule oil to the back surface of the sheet, making a plurality of copies In order to insert the intermediate layer between the upper sheet and the lower sheet, a developer layer is provided on the surface of the sheet and a microcapsule layer is provided on the back surface of the sheet, and a micro sheet is further provided on the same surface of the sheet. There is a single copy sheet coated with both a capsule and a developer. The above microcapsules are prepared by dissolving an electron-donating color-forming compound in capsule oil and dissolving the solution in a known manner, for example, a coacervation method, an interfacial polymerization method, an internal polymerization method, a phase separation method, an external polymerization method, or the like. Can be produced by various microencapsulation methods.

Examples of the electron-donating color-forming compound include triarylmethane compounds, diarylmethane compounds, rhodamine-lactam compounds, fluoran compounds, indolylphthalide compounds, pyridine compounds, spiro compounds, Various known compounds such as a fluorene compound and a phenothiazine compound are exemplified. As the capsule oil, for example, various kinds of cottonseed oil, castor oil, kerosene, paraffin, chlorinated paraffin, naphthenic oil, alkylated biphenyl, alkylated terphenyl, alkylated naphthalene, diarylalkane, hydrogenated terphenyl, dialkyl phthalate, etc. Oils can be mentioned. These capsule oils may be used alone or in combination.

[0021]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.
In addition,% represents weight%. Example 1 Zinc 3,5-di (α-methylbenzyl) salicylate 20
g, 1 g of glycerol, 0.5 g of sodium polystyrene sulfonate, and 200 g of water, were subjected to atomization and dispersion treatment with a sand grinder so that the average particle diameter of the developer dispersion particles became 1.5 μm, and the mixture was developed. An aqueous dispersion of the agent composition was obtained. 100 g of a 10% aqueous solution of polyvinyl alcohol (PVA-117, manufactured by Kuraray) was added to the aqueous dispersion.
0% carboxy-modified SBR latex (SN-307,
10g and calcium carbonate 12
0 g was added, and water was added so that the solid content concentration became 20%, to obtain a water-dispersed coating solution of a developer. The aqueous dispersion coating solution of the color developer composition is applied to a high-quality paper (50 g / m ² ) so that the coating amount (weight of the color developer layer) when dried becomes 5.0 g / m ² and dried. A pressure-sensitive recording sheet (lower sheet) was prepared.

Example 2 In Example 1, 3,5-di (α-methylbenzyl)
Instead of using 20 g of zinc salicylate, a method described in Example 1 was repeated, except that 20 g of a zinc salt of a polystyrene salicylic acid resin produced by the method shown in the following Reference Example was used. Particle size 1.6 μm
Was obtained, and a pressure-sensitive recording sheet was prepared.

Reference Example 152 g of methyl salicylate, 37 g of 98% sulfuric acid and 500 ml of 1,2-dichloroethane were charged into a glass reactor, and 384 g of 4-methylstyrene was added dropwise at 0 to 2 ° C. while stirring the solution. The solution was fed using a funnel over 6 hours. After the supply, the mixture was further stirred at the same temperature for 3 hours. After neutralization with a 5% by weight aqueous solution of sodium hydroxide, the mixture was heated to distill off 1,2-dichloroethane. Further, an aqueous solution consisting of 40 g of sodium hydroxide and 1000 g of water was added, and the mixture was heated and stirred at 95 ° C. for 6 hours. After adding 3000 g of water to the solution, zinc sulfate 7
An aqueous solution consisting of 145 g of hydrate and 2000 g of water was added dropwise over 1 hour. After stirring at room temperature for 2 hours, the mixture was filtered, washed with water, and dried to obtain a colorless zinc salt of salicylic acid resin 53.
0 g was obtained. The softening point was 112 ° C.

Example 3 75 g of 3,5-di (α-methylbenzyl) salicylic acid
A mixture of 25 g of 3- (α-methylbenzyl) -5- (1,3-diphenylbutyl) salicylic acid was dissolved at 30 ° C. in an aqueous solution consisting of 11 g of sodium hydroxide and 500 g of water. 39.3 g of zinc sulfate heptahydrate and water 2
An aqueous solution consisting of 00 g was added dropwise over 30 minutes. After dripping, 3
After stirring for 0 minutes, toluene (100 g) was added to the aqueous solution in which the mixed zinc salt of the salicylic acid derivative was precipitated, and after stirring, the toluene layer was separated. The toluene solution is heated at 50 ° C.
After the temperature was increased, 7 g of glycerol was added, and 500 g of a 5% aqueous solution of polyvinyl alcohol (PVA-117, manufactured by Kuraray) was further added. Using a homomixer [AM-7, manufactured by Nippon Seiki Co., Ltd.], 10,000 times per minute The emulsion was emulsified at a rotation speed of 10 minutes to obtain an oil-in-water emulsion. Heating the emulsion,
Toluene and a part of water were distilled off to obtain an aqueous dispersion (solid concentration: 30%) of the developer composition having an average particle diameter of the developer dispersed particles of 1.3 μm. Next, calcium carbonate 120
g, activated clay 30 g, zinc oxide 40 g, 40% sodium hexametaphosphate aqueous solution 5 g and water 230 g were dispersed with a sand grinder to an average particle diameter of 2 μm to obtain a pigment dispersion. To 50 g of this pigment dispersion, 10%
40 g of an aqueous polyvinyl alcohol solution and an aqueous dispersion of the above-described developer composition were added, and water was further added so that the solid content concentration became 20% to obtain an aqueous dispersion of the developer. The aqueous dispersion coating solution of the color developer is applied to a high-quality paper (50 g / m ² ) so that the coating amount (weight of the color developer layer) when dried becomes 5.0 g / m ² and dried. , Pressure-sensitive recording sheet (lower sheet)
Was prepared.

Example 4 The procedure of Example 3 was repeated, except that 7 g of glycerol was used instead of 7 g of glycerol, and 5 g of 1,3-diphenyl-1-butene which is a linear dimer of styrene. According to the method described in 1 above, an aqueous dispersion of the developer composition having an average particle diameter of the developer-dispersed particles of 1.2 μm was obtained, and a pressure-sensitive recording sheet was produced.

Example 5 100 g of a zinc salt of a polystyrene salicylic acid resin produced in the reference example, 7 g of glycerol, 4 g of 1,3-diphenyl-1-butene which is a chain dimer of styrene, and a cyclic dimer of styrene 2 g of a certain 1-methyl-3-phenylindane was dissolved in 100 g of xylene to prepare a xylene solution. This xylene solution is mixed with 80 g of water containing 0.2 g of sodium carbonate, 1 g of acrylamide / ethyl acrylate copolymer (weight average molecular weight 2500) and 2 g of polyvinyl alcohol by a homomixer at 80 min / min.
The emulsion was added while being rotated at a rotation number of 00 to obtain an emulsion. After 150 g of water was added to this emulsion, the emulsion was heated to distill off xylene and some of the water, and the developer composition had an average particle diameter of the developer dispersion particles of 1.2 μm. (Solid content: 30%) was obtained. Next, calcium carbonate 120 g, activated clay 30 g, zinc oxide 40 g, 40 g
5g aqueous solution of sodium hexametaphosphate and 230g of water
Was dispersed with a sand grinder to an average particle diameter of 2 μm to obtain a pigment dispersion. 50 g of this pigment dispersion
, 40 g of a 10% aqueous solution of polyvinyl alcohol and an aqueous dispersion of the above-described developer composition were added.
Water was added so as to be 20% to obtain a water-dispersed coating solution of a developer. A water-dispersed coating solution of the color developer was coated on a high-quality paper (50 g / m2).
² ) In addition, the coating amount (weight of the color developer layer) at the time of drying was 5.0.
g / m ² and dried to prepare a pressure-sensitive recording sheet (lower sheet).

Example 6 In Example 5, 7 g of glycerol, 4 g of 1,3-diphenyl-1-butene which is a chain dimer of styrene, and 1-methyl-3-phenylindane which is a cyclic dimer of styrene were used. Instead of using 2g, 7g glycerol
According to the method described in Example 5, except that 6 g of a mixture of 2 to 10-mers of styrene and styrene was used, an aqueous dispersion of a developer composition having an average particle diameter of developer dispersion particles of 1.2 μm was prepared. Thus, a pressure-sensitive recording sheet was produced.

COMPARATIVE EXAMPLE 1 The procedure of Example 1 was repeated except that glycerol was not used, except that the water content of the developer composition was 1.5 μm. A dispersion was obtained, and a pressure-sensitive recording sheet was produced. Comparative Example 2 In Example 5, 7 g of glycerol, 4 g of 1,3-diphenyl-1-butene which is a chain dimer of styrene, and 2 g of 1-methyl-3-phenylindane which is a cyclic dimer of styrene were used. Other than that, the average particle diameter of the developer-dispersed particles was 1.2 according to the method described in Example 5.
A μm aqueous dispersion of the developer composition was obtained, and a pressure-sensitive recording sheet was prepared.

The pressure-sensitive recording sheet (lower sheet) produced as described above was evaluated by the following method. Evaluation of pressure-sensitive recording sheet (low-temperature coloring test) Each pressure-sensitive recording sheet (lower sheet) prepared in Examples and Comparative Examples and crystal violet lactone (CVL) are contained as main electron-donating color-forming compounds. Commercially available upper sheet for blue coloring coated with microcapsules to be coated [N-4 manufactured by Mitsubishi Paper Mills, Ltd.]
0] was stored in a thermo-hygrostat at 5 ° C. and 30% RH for 5 hours. Next, in the constant temperature and humidity chamber, both application surfaces of the upper sheet and the lower sheet are overlapped so as to face each other, and 300 kg /
Color was developed for 1 second under a load pressure of cm ² . After pressing, 30
After 2 seconds, the color density was measured using a Macbeth reflection densitometer. Further, after storing the colored lower paper in the same environment for 24 hours, the color density was measured in the same manner. The results are shown in Table 1 (Table 1). The color development density indicates that the larger the numerical value, the deeper the color.

[0030]

[Table 1] From the results in Table 1, it can be seen that the pressure-sensitive recording sheet coated with the developer composition of the present invention develops a deep color in a short time under a low-temperature environment, and thus has excellent initial color-forming properties at a low temperature. It has been found.

[0031]

According to the present invention, it has become possible to provide a developer composition for a pressure-sensitive recording sheet having excellent low-temperature color developability, and a pressure-sensitive recording sheet formed by applying the composition.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-131672 (JP, A) JP-A-2-261690 (JP, A) JP-A-4-269583 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) B41M 5/155 B41M 5/30

Claims (2)

(57) [Claims] 1. A pressure-sensitive recording sheet containing a developer containing a polyvalent metal salt of a salicylic acid derivative as a component and glycerol in an amount of 0.5 to 20% by weight based on the developer . Developer composition. 2. A pressure-sensitive recording sheet obtained by applying the developer composition for a pressure-sensitive recording sheet according to claim 1 to a support.