JPH01141785A - Color developing sheet for pressure-sensitive copying paper - Google Patents

Abstract

PURPOSE:To prevent a deterioration of color developing ability during storage at high temperature by providing a color developing agent layer containing a multivalent metallized substance of salicylic acid resin of specific composition and a semi-synthesized solid acid with Mg component introduced in an acid- treated clay mineral on a support. CONSTITUTION:Ester salicylate expressed by a formula I (R1 is a C1-12 alkyl group, an aralkyl group, an aryl group and a cycloalkyl group) is caused to react with a stylene derivative expressed by a formula II (R2, R3 are H, a methyl group; R4 is H, a C1-4 alkyl group). Then a produced resin composition is subjected to hydrolysis. After this, a multivalent metallized/substance of salicylic acid resin is obtained by reaction with a multivalent metallic salt. Then a color developing layer consisting of the multivalent metallized substance and a semi-synthesized solid acid with Mg and/or Al component introduced in an acid-treated clay mineral, is applied to from a color-developing sheet for pressure-sensitive copying paper.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for forming an image by reacting with a basic leuco dye.
This invention relates to a color developer sheet for pressure-sensitive copying paper.

More specifically, the present invention relates to a color developing sheet characterized in that (^) a salicyl synthetic metal compound polyvalent metal compound and (B) a semi-synthetic inorganic solid acid are used as acidic color developers.

[Conventional technology]

Pressure-sensitive copying paper is also called carbonless paper, and is a type of copying paper that develops color under mechanical or impact pressure, such as when used in writing or typewriting, and is capable of making multiple copies at the same time, and is called a transfer type copying paper. , or single-coloring paper, the coloring mechanism of which is based on a coloring reaction between an electron-donating colorless dye and an electron-accepting color developer. Taking a transfer type pressure-sensitive copying paper as an example, this will be explained as shown in FIG. 1 as follows.

On the back side of the top paper 1 and the middle paper 2, microcapsules 4 with a diameter of several microns to more than ten microns are applied, which are made by dissolving a colorless pressure-sensitive dye in non-volatile oil and wrapping it in a polymer film such as gelatin. has been done. The surfaces of the middle paper 2 and the top paper 3 are coated with a paint containing a color developer 5 which has the property of causing a reaction and color development when it comes into contact with the above-mentioned pressure-sensitive dye. To make a copy, press top - (middle) - (middle)
- If you stack them in the order shown below (the dye-containing coated surface and the developer-containing coated surface face each other) and apply local pressure such as writing pressure 6 or typing pressure, the capsule 4 in that area will break and the pressure-sensitive dye A copy record is obtained by transferring the solution to the color developer 5.

As an electron-accepting color developer, (1) USP 2,712
．． (2) Inorganic solid acids such as acid clay and attapulgide disclosed in Japanese Patent Laid-Open No. 58-217389, etc.; Synthetic solid! [, (3) Substituted phenol and diphenol II disclosed in Japanese Patent Publication No. 40-9309 [, (4) p-substituted phenol-formaldehyde polymer disclosed in Japanese Patent Publication No. 42-20144, (5) Special Public Service 1977-10
Aromatic carboxylic acid metal salts disclosed in Japanese Patent No. 856 and Japanese Patent Publication No. 52-1327 have been proposed, and some of them have been put into practical use.

The performance conditions that a color developer sheet should have include not only excellent coloring properties that remain unchanged immediately after sheet production and even after long-term storage, but also little yellowing during storage and exposure to sunlight and other radiation, and a color image that is robust and resistant to radiation. Water or OK! ! Examples include not easily disappearing or discoloring due to peonies.

Conventionally proposed color developers and sheets coated with the same have advantages and disadvantages in terms of performance. For example, inorganic solid acids are inexpensive, but they absorb gas and moisture in the air during storage, causing yellowing of the paper surface and a decline in coloring performance, while substituted phenols have insufficient coloring properties and the density of colored images is reduced. P-phenylphenol-novolak resin, which is commonly used as a low-P-substituted phenol-formaldehyde polymer, has excellent color development, but the coated paper is exposed to sunlight or during storage (particularly when exposed to nitrogen oxidation in the air). (objects) turn yellow, and colored images fade significantly. Further, although aromatic carboxylic acid metal salts have good coloring properties, yellowing properties, and fading properties due to light, their resistance to water or plasticizers is still not sufficient.

In addition, the conventional pressure-sensitive copying paper color developing sheet had a problem in that the coloring ability, especially the initial coloring density, decreased when it was stored for a long period of time or at high temperatures after being coated and produced.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a color developer sheet for pressure-sensitive copying paper using a new color developer which improves the above-mentioned drawbacks.

[Means for solving problems]

The present inventors have completed the present invention as a result of diligent meter reading to achieve the above object.

That is, the present invention provides salicylic acid esters represented by the following general formula (II) on a support: A resin composition obtained by reacting a styrene derivative represented by Bi4 (wherein Rt, R3 represents a hydrogen atom or a methyl group, and R4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) A polyvalent metal compound of salicylic acid, which is characterized by hydrolyzing and then reacting with a polyvalent metal salt, and a semi-synthetic solid acid in which magnesium and/or aluminum components are introduced into a treated clay mineral. This is a color developer sheet for pressure-sensitive copying paper, which is provided with a color developer layer that emits a sound.

The new color developer sheet of the present invention has better color development than conventional color developer sheets! (especially excellent color development speed and low-temperature color development speed), and the color image has excellent resistance to browning caused by water, solvents, light, etc., and yellowing caused by gas and light on the paper surface. It has the advantage of being able to provide a color developing sheet at a low cost, which has very little tendency to tend, has excellent printability and fIi printing characteristics, and is very advantageous in handling and storage stability.

Furthermore, the color developer sheet of the present invention includes a renamed inorganic color developer,
Another feature is that it significantly improves the tendency for color development performance (particularly color development speed) to decline after long-term storage or high-temperature storage, which is a common problem with color developer sheets using resin-based color developers. It has the following.

The polyvalent metallized salicylic acid resin (A) used in the present invention can be obtained by the following method.

That is, a styrene derivative is subjected to a free-sol fluorofluorination reaction with a salicylic acid ester in the presence of a strong acid catalyst (hereinafter referred to as the first-stage reaction), and the resulting resin composition is hydrolyzed (hereinafter referred to as the second-stage reaction), Furthermore, this hydrolyzed resin composition is reacted with a polyvalent metal salt (hereinafter referred to as the third stage reaction) to produce the resin composition.

The salicylic acid resin produced in the first and second stages has never been disclosed before, and the present inventors newly discovered it and filed a separate patent application (Japanese Patent Application No. 62-20
1831).

The salicylic acid esters used in this first stage reaction include methyl salicylate, ethyl salicylate, n-propyl salicylate, isopropyl salicylate, n-butyl salicylate, itbutyl salicylate, tart-butyl salicylate, isoamyl salicylate, and salicylic acid. Industrially preferably inexpensive Methyl salicylate.

Next, the styrene derivatives defined by the general formula (■) used in this reaction include styrene, O-methylenestyrene, m-methylenestyrene, p-methylenestyrene, 0-ethylenestyrene, p-ethylenestyrene,
-isopropylstyrene, m-isopropylstyrene,
Examples include, but are not limited to, p-tert-7'tylstyrene, α-methylenestyrene, β-methylenestyrene, etc. Industrially preferred is styrene, which is inexpensive.

The amount of the styrene derivative to be used is 1 to 20 molar ratio, preferably 2 to 1O·molar ratio to the salicylic acid ester, and the average molecular weight of the resin is in the range of 50 to 10,000.

A strong acid catalyst is generally used in this general reaction, and the reaction may be carried out in the presence of a solvent inert to the reaction.

The salicylic acid ester resin obtained in the first stage reaction is then hydrolyzed using an acid or alkaline aqueous solution.

Several known methods can be applied to obtain the polyvalent metal compound used in the present application from the salicylic acid resin obtained by hydrolysis as described above.For example, (1) adding alkali metal hydroxide to the resin; , carbonate, alkoxide, etc. to obtain an alkali metal salt of the resin or an aqueous solution, alcohol solution, or water-alcohol mixed solution of the resin, and then react with a water-soluble polyvalent metal salt. . Approximately 0.5 to 1 per mole of salicylic acid in the resin
It is desirable to react gram equivalents of the water-soluble polyvalent metal salt.

(2) It can be produced by mixing a resin and a polyvalent metal salt of an organic carboxylic acid such as formic acid, acetic acid, propionic acid, valeric acid, caproic acid, stearic acid or benzoic acid, and heating and melting the mixture. In some cases, a basic substance such as ammonium carbonate, ammonium bicarbonate, ammonium acetate, or ammonium benzoate may be added and melted by heating. (3) Resin and polyvalent metal carbonates, oxides, and water It can be produced by heating and melting an oxide with a basic substance such as organic ammonium caproate such as ammonium formate, ammonium acetate, ammonium caproate, ammonium stearate, and ammonium benzoate.

The metal of the metallized salicylic acid condensate used in the present invention includes metals excluding alkali metals such as lithium, sodium, and potassium. Preferred polyvalent metals include magnesium, aluminum, calcium, copper, zinc, tin, Examples include barium, cobalt and nickel. Among these, zinc is particularly effective.

The polyvalent metallized product of the salicylic acid condensate used as the color developer of the present invention includes:
Of course, the present invention can also be implemented by blending and co-using an appropriate amount of a benzotriazole type, benzophenone type, or nickel complex type-heavy ring oxygen quencher! Included in a.

The semi-synthetic inorganic solid acid used as the other component (B) of the present invention is a layer consisting of regular tetrahedrons of silica as disclosed in JP-A-57-15996 or JP-A-58-217389. According to electron beam diffraction, it shows a diffraction pattern based on crystals with a layered structure consisting of regular tetrahedrons of silica, but according to X-ray diffraction, the above-mentioned It is a white fine powder that does not substantially show a diffraction pattern based on a layered structure and contains at least silicon, magnesium and/or aluminum as elements other than oxygen, and after acid treatment of a solid such as acid clay, magnesium and/or It can be obtained by reacting with an aluminum compound and reintroducing magnesium and/or aluminum components.

Such a semi-synthetic solid acid itself has color developing ability and a large specific surface area, and is extremely useful as a pigment for coating white paper.

When a semi-synthetic solid acid color developer having such color developing ability is used alone as a color developer for pressure-sensitive copying paper, the color fastness to light and water of the developed color image is insufficient, and it cannot be put to practical use as it is. The development of these synthetic solid acid color developers is rapidly progressing, and proposals to overcome the drawbacks of such synthetic solid acid color developers have already been proposed in JP-A No. 58-162375.
No. 58-162376, No. 58-162377, No. 58-162378, No. 60-208282, No. 6
No. 1-49886, etc. These methods attempt to improve the physical properties of the color developing sheet by using the semi-synthetic solid acid in combination with a phenol compound with a specific chemical structure, a polyvalent metal salt of a salicylic acid derivative, or a thiourea compound, but unfortunately, However, it has not been possible to completely solve the drawbacks of the semi-synthetic solid acids, which are the lack of light resistance and water resistance of colored images, and in some cases, the yellowing tendency of the paper surface is promoted, so it has not been put into practical use. not present.

As described above, the present invention is a color developer sheet containing (A) a novel polyvalent metallized salicyl #condensate and (B) a semi-synthetic solid acid as color developer components.

In order to produce the color developing sheet of the present invention, in addition to the color developers described above (A) and (B), other white gradients (such as natural and synthetic metal oxides, hydroxides, or carbonates) may be used as desired. Of course, the addition and use of the above is also included in the practice of the present invention.

Further, if necessary, known acidic color developers such as phenol formaldehyde resin, polyvalent metal salts of aromatic carboxylic acids, etc. may be used in combination.

In the present invention, the salicylic acid condensate polyvalent metal compound is used in advance in the form of an aqueous suspension of microparticles for boat fishing.

To prepare the color developer sheet of the present invention, in addition to (a) a salicylic acid cocondensed resin polyvalent metal compound (generally used as a pre-pulverized aqueous suspension), (b) a semi-synthetic solid acid,
(C) Binders (for example, synthetic rubber latex, modified starches, polyvinyl alcohol or modified polyvinyl alcohols, etc.), (d) Others (anti-dusting agents, fluorescent whitening agents, viscosity property modifiers, antifoaming agents) A method is used in which a water-based coating solution is prepared in advance with a viscosity and a solid content depending on the coating method to be used, and the coating solution is coated on a support such as paper or film and dried.

As a coating method, an en-knife coater, a bar coater, a blade coater, a gravure coater, a roll coater, etc. are used for boat fishing.

In the aqueous coating liquid used in the present invention, (A) salicylic acid bath metal polyvalent metallization is 2 to 40% by weight of the total solid content;
(B) The semi-synthetic solid acid generally contains 30 to 90% by weight, and the binder component generally contains 5 to 40% by weight.

The ability of the semi-synthetic solid acid used in the present invention as a color developer is most effectively expressed when the system is weakly alkaline. is common.

The amount of water-based coating liquid applied to the support is 1gown by dry weight.
The amount is preferably 2 to 10 g/#.

The color developer sheet of the present invention has the advantage that the amount of color developer subcomponents and coating liquid to be applied is small, and the concentration, viscosity, etc. of the aqueous coating liquid can be changed over a relatively wide range, and the mechanical and thermal Due to its excellent mechanical stability, it can be applied both on-machine and off-machine, which has great advantages not only in terms of printing performance but also in the pressure-sensitive copying paper manufacturing process.

[Action and effect]

The present invention provides a novel color developer sheet for pressure-sensitive copying paper that uses (^) a novel polyvalent metallized salicylic acid resin and (B) a semimetal-forming inorganic solid acid as a color developer and has extremely excellent performance.

The color developer sheet of the present invention differs from conventionally known color developer sheets with respect to the physical properties required for pressure-sensitive copying paper: (1) It provides excellent coloring performance (coloring speed, density) and, in particular, poses no problems when using pressure-sensitive copying paper. The color development performance (color development speed) at low temperatures in winter or outdoors is significantly improved.

(2) Excellent stability of colored images upon exposure to light or contact with solvents such as plasticizers.

(3) The colored image has excellent water resistance and does not disappear under humid conditions or upon contact with water.

(4) - There is very little change in coloring ability even after long-term storage or storage at high temperatures.

(5) The coated surface does not yellow even when it comes into contact with light or NOx gas components in the air.

(6) It has extremely excellent characteristics such as excellent printability and desensitization printing characteristics, and it has become possible to expand its use to applications for which conventional pressure-sensitive paper was unsuitable, and its practical significance is extremely large.

〔Example〕

The present invention will be explained in detail below using Examples and Comparative Examples.

Prior to Examples, a method for manufacturing a color developer sheet and a method for evaluating its performance as a pressure-sensitive copying paper will be described below.

The color developer used on each side was wet milled in the presence of a small amount of anionic polymeric surfactant to form an aqueous suspension with a solids content of 40% by weight (average particle size 2.5μ).

Next, using this suspension, an aqueous coating solution (solid content: 35% by weight, pH 9.8) having the following composition is prepared.

Standard aqueous coating composition Solid content weight comparison
15 Semi-synthetic inorganic solid acid 100 Synthetic rubber latex i.

Oxidized starch 12 Anti-dusting agent 1 Notes Semi-synthetic inorganic solid acid Mizusawa Chemical Zilton 35-1 Synthetic rubber latex Mitsui Toatsu Polylac 52-A Oxidized starch Egg cornstarch Ace B Anti-dusting agent Nissin Chemical DEF-922F above water-based coating liquid 40g/+ using Meyer bar coater
A pressure-sensitive copying paper developing sheet was prepared by applying and drying the mixture to a dry coating amount of 7 g/m' on a high-quality paper of 1.5 g/m'.

The method for evaluating the performance of the color developing sheet thus obtained as a pressure-sensitive paper is as follows.

(1) Color development speed and density (conducted in a thermostatic chamber at 20°C and 65χRH) Commercial blue coloring paper containing crystal violet lactone (CVL) as the main pressure-sensitive dye (NW-4 manufactured by Jujo Paper Co., Ltd.)
0T), the color developing sheet (lower layer paper) obtained in the example
The two cylinders were placed one on top of the other with their fabric surfaces facing each other, and the colors were engraved using an electronic typewriter. The reflectance after 30 seconds and 24 hours of imprinting was measured using a Σ-80 color difference meter (manufactured by Nippon Denshoku) and expressed as a Y value.

(2) Low-temperature color development speed After storing the color developing sheet obtained in the Example and the commercially available top paper for blue color development (Jujo NW-40?) in a constant temperature room at 2°C overnight, combine the cloth surfaces of both types. Linear pressure 50Kg/C1
Pass through a calendar roll to develop color.

10 seconds after color development, measure the Ho color density using a Σ-80 color difference meter.
Display by value. The smaller the Y value, the better the color development performance at low temperatures.

(3) Light fastness of colored image The color developing sheet developed by the method in (1) is exposed to direct sunlight outdoors on a sunny day for 6 hours, and the density of the colored image after the test is expressed as a Y value.

(4) Plasticizer resistance of color image Prepare melamine-formaldehyde resin membrane microcapsules with an average particle size of 5.0μ with dioctyl phthalate (DOP) as the core material, and apply a coating liquid with a small amount of starch-based binder using an air knife. [)OP microcapsule-coated paper is prepared by coating and drying it on high-quality paper using a coater so that the dry coating amount becomes 58/cd. The [10P micro-pressure coated paper and the coloring surface of the color developing sheet developed in (1) above were placed opposite each other, and then passed through a super calendar roll having a linear pressure of 100 kg/cm to uniformly apply DOP to the coloring surface. Let it penetrate.

The concentration one hour after the test is expressed as a Y value using a Σ-80 color difference meter. The lower Y(i and the smaller the difference from the pre-test value, the better the plasticizer resistance of the colored image.

(5) Water resistance of colored image The color developing sheet developed by the method of (1) was immersed in water for 2 hours, and changes in the density of the colored image were observed with the naked eye.

(6) Yellowing of color D sheet (6-1) Yellowing due to NO, based on JIS L-1055 (nitrogen oxide gas fastness test method for dyed products and dyes)
The sample was stored for 1 hour in a sealed container in an atmosphere of NOx gas generated by the reaction between (sodium nitrite) and HiPOa (phosphoric acid), and the degree of yellowing was examined.

One hour after the end of the test, the -B value is displayed using a Σ-80 color difference meter. WB (−B of large i and untested sheet)
The smaller the difference from the value, the less yellowing under the N08 atmosphere.

(6-2) Yellowing due to light The color developing sheet is irradiated with a carbon arc fade meter (manufactured by Suga Test Instruments) for 4 hours, and after the test, the -B value is displayed using a Σ-80 color difference meter. The larger the WB value and the smaller the difference from the -B value of the untested sheet, the smaller the yellowing caused by light irradiation.

(7) Heat resistance of color developer sheet Evaluation was made by measuring the tendency for color development ability to decrease during long-term storage or high-temperature storage (in particular, changes in color density immediately after color development).

After each color developing sheet was stored in a constant temperature bath at 50°C for 100 hours, commercially available top paper for blue color development (Jujo NW) was used.
-407) and passed through a calender roll with a linear pressure of 50 kg/am to develop color.

The color density after 10 seconds Ho and 24 hours after color development is Σ-80
Y value with color difference meter Y value. The smaller the change compared to the untreated color development density that was similarly subjected to the color development test, the better the long-term storage and heat stability.

Synthesis Example 1 Methyl salicylate 15.2g (0.1 mol), 1.2-
3.75 g of dichloroethane 5 (ld, 96% concentrated sulfuric acid) was placed in a glass reactor, and 52 g (0.5 mol) of styrene was added dropwise thereto over 6 hours at 0 to 2° C. while stirring vigorously.

Thereafter, the reaction was completed by aging at the same temperature for 3 hours.

Next, 50 g of an 85% aqueous sulfuric acid solution was added to the reaction solution and heated to distill off 1,2-dichloroethane.

Acetic acid 50H1 was added to this, and a hydrolysis reaction was carried out under reflux for 18 hours. After the reaction was completed, the reaction solution was poured into 30 ml of water and allowed to stand, causing a brown resin to precipitate.

This was tilted to discard the upper layer of water, and was further washed twice with 300 d of warm water.

The weight average molecular weight of the obtained salicylic acid cocondensation resin was 96.
It was 0. This resin is placed in another reactor and the temperature is 150~
A premixed mixture of 16.3 g of zinc benzoate and Log ammonium bicarbonate at 160° C. was gradually added over 30 minutes. After the addition, stirring was continued for 1 hour at the same temperature, the mixture was discharged, cooled, and then ground to obtain 79.5 g of zinc benzoate modified salicylic acid resin. The softening point of this material in JIS-
8 when measured with a ring and ball softening point measuring device according to 2548
The temperature was 2°C.

This is referred to as salicylic acid resin polyvalent gold II (A).

Synthesis Example 2 22.8 g (0.1 mol) of benzyl salicylate, 15 d of methylene chloride, and 15.9 g of 96% concentrated sulfuric acid were charged into a glass reactor, and 83.2 g (0.8 mol) of styrene was heated at a temperature of 5 to 12 mol. The mixture was added dropwise and reacted over 8.5 hours at °C.

After aging at the same temperature for 3 hours, the mixture was neutralized with diluted ammonia water and separated to obtain a methylene chloride solution of the co-condensed resin.

The weight average molecular weight of this co-condensed resin was 1,380.

Next, the solvent was distilled off while heating the above solution, and 12
The temperature was raised to 0''C. 35g (0.05mol) of a 20% zinc chloride aqueous solution was added dropwise to the slightly viscous cocondensation resin and stirred under reflux for 12 hours.Then, the temperature was raised to 140'C.
After stirring for 2 hours, 250 d of toluene was added. Next, while maintaining the temperature at 70°C to -80°C, 7.3g (0.12 mol) of 28% aqueous ammonia was added dropwise to the mixture and stirred for 1 hour. The mixture was then allowed to stand, the lower aqueous layer was separated and removed, and the temperature was raised to distill off toluene. The reddish-brown resin liquid was discharged, cooled, and then pulverized to obtain 93.5 g of a zinc-modified salicylic acid cocondensation resin. The softening point of this product was 76° C. This was designated as salicylic acid resin polyvalent metal (Bl).

Synthesis Example 3 In the first stage reaction of Synthesis Example 1, 38.4 g (0.3 mol) of P-methylstyrene was used instead of styrene, and a similar reaction was carried out. Next, 80 g (0.2 mol) of a 10% aqueous sodium hydroxide solution was added to this reaction solution, and the temperature was increased to distill off the solvent. Next, the 6 reaction solution that was subjected to a hydrolysis reaction for 12 hours at a temperature of 100 to 10°C was a slightly cloudy solution, and after diluting it by adding 850 d of water, 400 g of a 5% zinc sulfate aqueous solution (0.07 mol) was added dropwise over 3 hours at a temperature of 20-25°C. The precipitate was filtered, washed with water, and dried under vacuum to obtain 52 g of white salicylic acid resin zinc salt. The softening point was 112°C.

This is referred to as salicylic acid resin polyvalent metal (C).

Synthesis Example 4 A salicylic acid cocondensation resin having a weight average molecular weight of 720 was obtained in the same manner as in Example except that α-methylstyrene was used instead of styrene in the reaction of Synthesis Example 1. Add 4.1g (0.05 mol) of zinc oxide to this resin and make 1,140 ~
When the reaction was carried out at a temperature of 150° C. for 2 hours, 76 g of a zinc-modified salicylic acid cocondensation resin was obtained which was reddish-brown and transparent. The softening point was 71°C.

This is referred to as salicylic acid resin polyvalent metal CD).

Implementation N1 Salicylic acid resin Zn compound obtained in Synthesis Example 1 was used as a color developer (
Using A), color developer sheet (1) is prepared using the standard aqueous coating solution formulation.
I got it.

Example 2 Salicylic acid resin Zn compound C obtained in Synthesis Example 2 as a color developer
Using B), color developing sheet (2) with the above standard aqueous coating liquid formulation.
I got it.

Example 3 Salicylic acid resin Zn compound obtained in Synthesis Example 3 was used as a color developer (
Using C), color developing sheet (3) with the above standard aqueous coating liquid formulation.
I got it.

Implementation g44 Salicylic acid resin Zn compound C obtained in Synthesis Example 4 as a color developer
Using D), color developing sheet (4) is prepared using the standard aqueous coating solution formulation.
I got it.

Example 5 Instead of 100 parts of semi-synthetic solid acid (Zilton 5S-1),
A color developing sheet (5) was obtained in the same manner as in Example 2 except that 5s-iso parts of Zilton and 20 parts of zinc oxide were used.

Example 6 Instead of 100 parts of semi-synthetic solid acid (Zilton 33-1),
Example 3 except that 180 parts of Jilton 5S and 20 parts of light calcium carbonate (Okutama Kogyo TP-123) were used.
A color developing sheet (6) was obtained in the same manner as above.

Comparative Example 1 Example 1 except that salicylic acid resin Zn compound was not used.
A color developing sheet (7) was obtained in the same manner as above.

Comparative Example 2 A color developer sheet (8) was obtained in the same manner as in Example 1, except that the same amount of p-phenylphenol formaldehyde resin (Mitsui Toatsu RB) was used as the color developer (A).

Comparative Example 3 In place of the semi-synthetic solid acid (Jilton 5S-1), activated clay (Mizusawa Chemical Co., Ltd., Jilton DR), which is conventionally known as a color developer, was used.
A color developer sheet (9) was obtained in the same manner as in Example 1 except that -1) was used.

Comparative Example 4 A color developer sheet ( 10) was obtained.

Comparative Example 5 A color developer sheet (11) was obtained in the same manner as in Example 1 except that Zn 3,5-di-tar t-butylsalicylate was used as the color developer (A).

Comparative Example 6 A color developing sheet (12) was obtained in the same manner as in Example 2 except that the same amount of light calcium carbonate was used in place of the semi-synthetic solid acid (Zilton 55-1).

Table 1 summarizes the performance evaluation results of the color developing sheets of Examples and Comparative Examples thus obtained as pressure-sensitive copying paper.

(Hereinafter, blank spaces) As is clear from Tables 1 to 1, the pressure-sensitive copying paper color developer sheet of the present invention does not satisfy the physical properties required for pressure-sensitive copying paper, and is an unprecedented color developer sheet.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the structure of pressure-sensitive copying paper. In FIG. 1, each symbol is as follows. 1-...Top paper 2...Middle paper 3-...Top paper 4
・--L microcapsule 5... Color developer 6--
・Writing pressure patent applicant: Mitsui Toatsu Chemical Co., Ltd. Drawing diagram-1

Claims (1)

[Claims] 1) (A) General formula (I) ▲ Numerical formula, chemical formula, table, etc. ▼ (I) (In the formula, R_1 is an alkyl group having 1 to 12 carbon atoms, an aralkyl group, an aryl group, or (Indicates a cycloalkyl group.) Salicylic acid esters represented by the general formula (II) ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (II) (In the formula, R_2 and R_3 represent a hydrogen atom or a methyl group, and R_4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.) salicylic acid, which is characterized by reacting a styrene derivative represented by the formula, hydrolyzing the resulting resin composition, and then reacting it with a polyvalent metal salt. Pressure-sensitive copying characterized by providing a color developer layer containing a polyvalent metallized resin and (B) a semi-synthetic solid acid in which magnesium and/or aluminum components are introduced into an acid-treated clay mineral. Color developer sheet for paper.