JPS63183876A - Color-developing sheet for pressure-sensitive copying paper - Google Patents

Abstract

PURPOSE:To impart a superior color-forming performance, by providing a color-developer layer containing a polyvalent metallized substance of a salicylic acid condensate, obtained by the reaction of a salicylic acid and a specific benzyl alcohol derivative, and a semi-synthetic solid acid. CONSTITUTION:A benzyl alcohol derivative in use is a compound shown by Formula (I) (where R1 represents hydrogen atom, lower alkyl group, lower alkoxy group, or halogen atom, R2 and R3 represent respectively hydrogen atom or methyl group, and R4 represents hydrogen atom or C1-C4 lower alkyl group), such as benzyl alcohol and 4-methylbenzyl alcohol. A resin is produced by adding predetermined amounts of a salicylic acid, the benzyl alcohol derivative, and an acid catalyst to be allowed to react with each other at a predetermined temperature. As the metal used in a metallized substance of a salicylic acid condensate, magnesium, aluminum, zinc, and others are used. A semi-synthetic inorganic solid acid is obtained by a method in which a solid, such as an acid clay, is subjected to acid treatment and, thereafter, allowed to react with a magnesium compound and/or an aluminum compound to reintroduce these components. To produce a color-developing sheet, an aqueous solution is prepared by mixing a binder group well in addition to the polyvalent metallized substance of salicylic acid co-condensation resin and the semi-synthetic solid acid, and this aqueous solution is coated on a substrate, such as a film, and dried. As a result, a superior color- forming performance is obtained.

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) a polyvalent metallized salicylic acid condensate 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, there are microcapsules 4 with a diameter of several microns to ten-odd microns, which are made by dissolving a colorless color-forming pressure-sensitive dye in non-volatile oil and wrapping it in a polymer film such as gelatin. It is coated. 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, (I) 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 acids, (3) Substituted phenol and diphenol H1 disclosed in Japanese Patent Publication No. 40-9309 (4) Japanese Patent Publication No. 42
ρ-substituted phenol-formaldehyde polymer disclosed in No.-20144, (5) Japanese Patent Publication No. 49-1085
Aromatic carboxylic acid metal salts and the like disclosed in Japanese Patent Publication No. 6 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. Examples include not easily disappearing or discoloring due to water or plasticizers.

Conventionally proposed color developers and sheets coated with them 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, resulting in yellowing of the paper surface. p-phenylphenol-novolac resin, which is most commonly used as a p-substituted phenol-formaldehyde polymer, has poor color-forming properties. Although excellent, the coated paper turns yellow when exposed to sunlight or during storage (particularly due to nitrogen oxides in the air), and the colored image fades 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 intensive studies to achieve the above object.

That is, the present invention provides a method in which (A) salicylic acid and monocatalytic formula (I) (wherein R is a hydrogen atom, a lower alkyl group, a lower alkoxy group, or a halogen atom, and Rt and Ih are each a hydrogen atom or methyl group, R4 is hydrogen atom or C8~
Magnesium and/or aluminum components were introduced into the polyvalent metal compound of the salicylic acid condensate obtained by the reaction with the benzyl alcohol derivative represented by ), which represents a C4 lower alkyl group, and (B) acid-treated clay mineral. This color developer sheet for pressure-sensitive copying paper is provided with a color developer layer containing a semi-synthetic solid acid.

The novel color developer sheet of the present invention has superior color development performance (in particular, excellent color development speed and low temperature color development speed) compared to conventionally disclosed color development sheets, and the color development sheet can be formed using water, solvents, etc. It has extremely excellent resistance to browning caused by light, etc., has very little tendency to yellow on the paper surface due to gas or light, and has excellent printability and desensitization printing properties, making it extremely advantageous in handling and storage. It has the advantage of being able to provide color developing sheets at low cost.

Furthermore, the color developer sheet of the present invention can be used with conventional inorganic color developers,
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.

As mentioned above, the salicylic acid condensate (A) used in the present invention is a composition obtained by reacting salicylic acid and the benzyl alcohol derivative represented by the general formula (I) in an acidic environment. The reaction between salicylic acid and a benzyl alcohol derivative can be carried out in an organic solvent or an inorganic solvent in the presence of an acid catalyst at a temperature of 110°C or higher, preferably 130°C or higher and 170°C or lower.

When the reaction temperature is low, the reaction time becomes long and side reactions such as esterification reactions occur frequently.

The benzyl alcohol derivative used as a reaction component is a compound represented by the general formula (I), and includes substituted benzyl alcohol and substituted benzyl alcohol lower alkyl ether, and specifically, the following compounds are exemplified. .

Benzyl alcohol, 3-methylbenzyl alcohol, 2-methylbenzyl alcohol, 3,4-dimethylbenzyl alcohol, α-methylbenzyl alcohol, 4-methyl-α-
Methylbenzyl alcohol, 2-methyl-α-methylbenzyl alcohol, 3-methyl-α-methylbenzyl alcohol, 4-ethyl-α-methylbenzyl alcohol, 4-ethyl-benzyl alcohol, 4-n-propylbenzyl alcohol, 4 -n-butylbenzyl alcohol, 4-chlorobenzyl alcohol, 4-chloro-α-
Methylbenzyl alcohol, 4-methoxybenzyl alcohol, 4-ethoxybenzyl alcohol, α,α-dimethylbenzyl alcohol, 4-methyl-α,α-dimethylbenzyl alcohol, 4-chloro-α. α-dimethylbenzyl alcohol, 4-ethyl-α,α-dimethylbenzyl alcohol, 4-butyl-α. α-dimethylbenzyl alcohol and methyl ether of the above compounds,
Examples include ethyl ether, propyl ether, butyl ether, but are not limited to these.

Among these compounds, alcohol type or methyl ether type compounds are preferably used because they have excellent reactivity with salicylic acid.

A general method for producing the resin used in the present invention is as follows:
A predetermined amount of salicylic acid, a benzyl alcohol derivative represented by general formula (I), and an acid catalyst are added and reacted at a predetermined temperature.

Water or alcohol produced as the reaction progresses is distilled out of the system.

After the reaction is complete, the contents are discharged, cooled, and then pulverized to obtain the desired product. In addition, if unreacted salicylic acid remains in the resin, it can be removed by washing the resin with hot water or using benzene, toluene, xylene, monochlorobenzene,
A method of dissolving it in an organic solvent such as methyl isobutyl ketone or cyclohexanone and washing with hot water is used.

Several known methods can be applied to produce the metallized product from the salicylic acid condensate thus produced. For example, it can be produced by reacting the alkali metal salt of the present resin with a water-soluble polyvalent metal salt in water or a solvent in which both are soluble.

That is, after reacting an alkali metal hydroxide, carbonate, alkoxide, etc. with a resin to obtain an alkali metal salt of the resin or an aqueous solution, alcohol solution, or water-alcohol mixed solution of the alkali metal salt, a water-soluble polyhydroxide is prepared. This is a method of producing it by reacting valent metal salts. It is desirable to react about 0.5 to 1.5 gram equivalents of water-soluble polyvalent metal salt per mole of salicylic acid in the resin.

It can also be produced by mixing a resin with 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. It can be produced by using oxides or halides and heating and melting them with organic ammonium carboxylates such as ammonium formate, ammonium acetate, ammonium caproate, ammonium stearate, ammonium benzoate, or basic substances such as ammonia.

When producing a metallized resin by heating and melting, the melting temperature is usually 100 to 180°C, and the reaction time depends on the resin composition, melting temperature, type of polyvalent metal salt, and amount used.
It takes about 1 to several hours. Regarding the amount of polyvalent metal salt used, organic carboxylates, carbonates, oxides, and hydroxides of polyvalent metals should be used so that the metal is present at 1% to about 20% by weight based on the total weight of the resin. It is desirable to use it.

There is no particular restriction on the amount of the basic substance used, but it is usually used in an amount of 1 to 15% by weight based on the total weight of the resin. When using a basic substance, it is more preferable to mix it with a polyvalent metal salt beforehand.

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 metalized product of the salicylic acid condensate used as the color developer of the present invention may contain a benzotriazole type, a benzophenone type, or a nickel complex type (during heavy ring oxygen quenching) in order to further improve light fastness and other properties. Of course, it is also included in the embodiment of the present invention to use an appropriate amount of blending and melting together.

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

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. However, there have already been proposals to overcome the drawbacks of such synthetic solid acid color developers, such as 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 salicylic acid condensate and (B) a semi-synthetic solid acid as color developer components.

In order to produce the color developer sheet of the present invention, in addition to the color developer (A) and (B), other white pigments (such as natural and synthetic metal oxides, hydroxides, or carbonates) may be added if desired. Of course, the addition and use of these are also included in the embodiments 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 polyvalent metallized salicylic acid condensate is generally used in advance in the form of an aqueous suspension of fine particles.

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 air knife coater, a bar coater, a blade coater, a gravure coater, a roll coater, etc. are generally used.

In the aqueous coating liquid used in the present invention, (A) polyvalent metallized salicylic acid condensate is contained in an amount of 2 to 40% by weight based on the total solid content;
(B) The semi-synthetic solid acid generally has a content of 30 to 90% by weight and a binder component of 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 1 g/m' in terms of dry weight.
More preferably, it is 2 to 10 g/m''.

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

[Action and effect]

The present invention provides a novel pressure-sensitive copying device with extremely excellent performance that uses (A) a polyvalent metal compound of a condensate obtained by reacting salicylic acid and a benzyl alcohol derivative and (B) a semi-synthetic inorganic solid acid as a color developer. Provides paper color developing sheets.

The color developer sheet of the present invention differs from previously known color developer sheets with respect to the physical properties required for a pressure-sensitive copying paper: (I) it provides excellent color development performance (color development speed, density); In particular, the color development performance (color development speed) at low temperatures in winter or outdoors, which is a problem when using pressure-sensitive copying paper, is significantly improved. 7(2)
It has excellent stability of colored images upon exposure to light and 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] 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 ratio color developer
15 Semi-synthetic inorganic solid acid 100 Synthetic rubber latex 10 Oxidized starch 12 Anti-dusting agent 1 Notes Semi-synthetic inorganic solid acid Mizusawa Chemical Zilton 5S-1 Synthetic rubber latex Mitsui Toatsu Polylac 52-A Oxidized starch Oji Cornstarch Ace B Dusting prevention Agent Nisshin Chemical DEF-922F The above water-based coating liquid was applied at 40g/m using a Meyer bar coater.
A color developer sheet for pressure-sensitive copying paper is prepared by applying and drying the mixture to a dry coating amount of 7 g/m2 on high-quality paper.

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

(I) Color development rate and density (20°C, 65χR1(
(Conducted in a thermostatic chamber) A commercially available top paper for blue coloring 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 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-40T) in a constant temperature room at 2°C overnight, combine the cloth surfaces of both cylinders to form a line. The color was developed by passing through a calender roll under a pressure of 50 kg, and the color density at 10 seconds after color development was measured using a Σ-80 color difference meter and expressed as a Y value. The smaller the Y value, the better the color development performance at low temperatures.

(3) Light fastness of color image The color developer sheet developed using the method (I) is exposed to direct sunlight outdoors on a sunny day for 6 hours, and the color image density 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 the coating liquid to which a small amount of starch-based binder was added using an air knife. DOP microcapsule-coated paper is prepared by coating and drying it on high-quality paper using a coater so that the dry coating amount is 5 g/c+i. After the OOP microcapsule-coated paper and the coloring surface of the color developing sheet colored in the above (I) are made to face each other, they are passed through a super calendar roll having a linear pressure of 100 Kg/am to uniformly penetrate the coloring surface with OOP. .

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

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

(6) Yellowing of developer sheet (6-1) Yellowing due to No. Based on JIS L-1055 (nitrogen oxide gas fastness test method for dyed products and dyes), the developer sheet was
The sample was stored for 1 hour in a closed container in a N0w gas atmosphere generated by the reaction between sodium nitrite) and H3P0a (phosphoric acid), and the degree of yellowing was examined.

One hour after the end of the test, the WB value is displayed using a Σ-80 color difference meter. The larger the WB value and the smaller the difference from the WB value of the untested sheet, the less yellowing in the N08 atmosphere.

(6-2) Yellowing due to light The developer sheet is irradiated with a carbon arc fade meter (manufactured by Suga Test Instruments) for 4 hours, and after the test, it is displayed as a WB value using a Σ-80 color difference meter. The larger the 1B value and the smaller the difference from the IIB value of the untested sheet, the smaller the yellowing caused by light irradiation.

(2) 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).

Each color developing sheet was stored in a constant temperature bath at 50°C for 100 hours, and a commercially available top paper for blue color development (Jujo N
40T) and passed through a calender roll with a linear pressure of 50 kg/cm to develop color.

Color density at 10 seconds 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.

(Left below) Synthesis g4-1 Add 2.5 g of p-toluenesulfonic acid to 160 g of 0-chlorotoluene and heat to 60°C, then add 125 g of α-methylbenzyl alcohol and 77 g of salicylic acid.
．． Add 5 g. The mixture is heated to 90° C. and the water produced by the reaction is continuously distilled off azeotropically. Thereafter, 0-chlorotoluene was distilled off and the residue was
- Stir with 560 d of aqueous NaOH solution and then dilute with 11 ml of water. The resulting solution is left at room temperature for several hours, and the oil layer that has separated on the surface is separated and removed. Thereafter, this aqueous solution was dropped into an aqueous solution of 47.7 gt of zinc chloride dissolved in 3001 d of water over a period of 10 minutes with strong stirring. The white precipitate obtained is then filtered off and compressed. Li again the resulting cake! The suspension was suspended in water, filtered and separated again, and the cake was pressed and dried under vacuum at 100°C to obtain 117 g of a Zn compound of a powdery salicylic acid-α-methylbenzyl alcohol condensate.

Synthesis Example-2 27.6 g (0.2 mol) of salicylic acid, 68 g (0.5 mol) of 4-methylbenzyl methyl ether, and 0.75 g of anhydrous zinc chloride as a catalyst were charged into a glass reactor, and the reaction temperature After aligning at 160″C for 4 hours,
The temperature was raised to 170°C, and methanol produced by reaction for 2 hours was distilled out of the system.

Next, the internal temperature is cooled to 100"C, 20 (ld) of methyl isobutyl ketone is added and dissolved, and then 50 (lal!) of warm water is added and stirred at 95-100 °C for 20 minutes to remove the aqueous layer. The separation operation was repeated two more times to remove unreacted salicylic acid.Then, the solvent was distilled off and the condensate was cooled to obtain 75 g of a reddish-brown transparent oily resin.The salicylic acid content of this resin was determined by titration. I found it to be 25.2wt%.
Met.

The liquid resin obtained above was dispersed in 700 g of water in which 5.7 g of caustic soda was dissolved, and when heated to 70° C., it was dissolved.

Next, while maintaining the temperature of the solution at 50°C, a solution prepared by dissolving 11.25 g of anhydrous zinc chloride (90% purity) in 250 m of water was added dropwise over 30 minutes while stirring.1. A white precipitate separated out.

After stirring at the same temperature for 2 hours, the mixture was filtered, washed with water, and dried to obtain 78.7 g of white powder. This was a zincated salicylic acid condensate, and the zinc content was 4.9%.

Synthesis Example 3 Nickel chloride hexahydrate (purity 9) was used instead of anhydrous zinc chloride.
Pale green salicylic acid condensate nickelide powder 7B, 5. I got it.

Synthesis Example 4 77.5 g of salicylic acid, 140.4 g of 4-methyl-α-methylbenzyl alcohol, and 06 g of p-toluenesnephonic acid-IHz are linearly combined at 120° C. for 3 hours with stirring. The water produced during the condensation is continuously distilled out of the system to complete the reaction. Thereafter, the mixture was continued to be cooled to 90° C., and 295% of an aqueous sodium hydroxide solution was added thereto. The resulting solution is left to stand at room temperature, and the solid by-products that have formed on the surface are filtered off. After this, add the remaining solution to 400 ml of water.
It is introduced into a solution of 50.3 g of 1 g of ZnC in arffi with vigorous stirring. The precipitate obtained is then filtered off and compressed. The obtained filter cake was dried under vacuum at a temperature of 50°C to obtain 148 g of a zincated powder of 4-methyl salicylate-α-methylbenzyl alcohol condensate.

Example 1 A color developer sheet (I) was obtained using the zincated product of the salicylic acid and α-methylbenzyl alcohol condensate obtained in Synthesis Example 1 as the color developer (A) and the standard aqueous coating formulation described above.

Example 2 A color developer sheet (2) was obtained using the above-mentioned standard aqueous coating formulation using the zincated product of the condensate of salicylic acid and 4-methylbenzyl-methyl ether obtained in Synthesis Example 2 as the color developer (A). .

Example 3 Salicylic acid-4-α obtained in Synthesis Example 3 as color developer (A)
- Color developer sheet (3) using a nickel compound of a condensate of methylbenzyl-methyl ether and using the standard aqueous coating formulation as described above.
I got it.

Example 4 A color developer sheet (4) was obtained using the standard aqueous coating liquid formulation using the zincated 4-methyl-α-methylbenzyl alcohol condensate salicylate obtained in Synthesis Example 4 as the color developer (A). .

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 55 to 180 parts of Zilton and 20 parts of zinc oxide were used.

Example 6 Instead of 100 parts of semi-synthetic solid acid (Zilton 5S-1),
80 parts of Jilton 55-1 and light calcium carbonate (
A color developing sheet (6) was obtained in the same manner as in Example 1 except that 20 parts of Okutama Kogyo TP-123) were used.

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

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 Color development was carried out in the same manner as in Example 1, except that the same amount of Zn-modified salicylic acid-p-nonylphenol-formaldehyde condensate (Schenectady Chemical) RJ-4002) was used as the color developer (A). A sheet (I0) was obtained.

Comparative Example 5 A color developer sheet (I1) was obtained in the same manner as in Example 1 except that Zn 3,5-di-tert-butylsalicylate was used as the color developer (A).

Comparative Example-6 A color developing sheet (I2) 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 (Jilton 5S-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 Table 1, the pressure-sensitive copying paper color developer sheet of the present invention is an unprecedented color developer sheet that satisfies the physical properties required for pressure-sensitive copying paper.

[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.--Bottom paper 2.--Middle paper 3-.--Bottom paper 4
...- Upper microcapsule 5-- Color developer 6--
・Writing pressure patent applicant: Mitsui Toatsu Chemical Co., Ltd. Drawing 1

Claims (1)

[Claims] 1) On the support are (A) salicylic acid and the general formula (I) ▲ mathematical formula, chemical formula, table, etc. ▼ (I) (in the formula, R_1 is a hydrogen atom, a lower alkyl group, a lower alkoxy salicylic acid condensate obtained by reaction with a benzyl alcohol derivative represented by a group or a halogen atom, R_2 and R_3 each represent a hydrogen atom or a methyl group, and R_4 represents a hydrogen atom or a lower alkyl group of C_1 to C_4. A pressure-sensitive copying paper comprising a color developer layer containing a polyvalent metal compound 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. 2) The color developer sheet for pressure-sensitive copying paper according to claim 1, wherein the benzyl alcohol derivative is 4-methylbenzyl methyl ether. 3) The color developer sheet for pressure-sensitive copying paper according to claim 1, wherein the benzyl alcohol derivative is α-methylbenzyl alcohol.