JPH01133780A - Preparation of multivalent metal compound of salicylic acid resin - Google Patents

Abstract

PURPOSE:To provide the title compound having excellent color developing property and not changed even after long-time preservation when being used as a color developer for a pressure sensitive copying paper, by bringing a specified styrene derivative into reaction with a salicylic acid ester to obtain a salicylic acid ester resin, hydrolyzing the ester resin, and bringing the hydrolyzate into reaction with a multivalent metal salt. CONSTITUTION:A salicylic acid ester of formula I is brought into reaction with a styrene derivative of formula II to obtain a salicylic acid ester resin, which is hydrolyzed, and the hydrolyzate is brought into reaction with a multivalent metal salt. A color developer sheet using a novel color developer constituted of the multivalent metal compound of the salicylic acid ester resin thus obtained is free of after-yellowing due to light and gases such as nitrogen oxide contained in air, gives developed color images stable to light and plasticizers or the like, is free of lowering in developed color density, and has favorable water resistance. In the formula, R1 is a 1-12C alkyl, aryl or cycloalkyl, each of R2 and R3 is H or methyl, and R4 is H or a 1-4C alkyl.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a novel polyvalent metal compound of salicylic acid resin used as a color developer for pressure-sensitive copying paper.

1. Prior Art] Pressure-sensitive copying paper is also called carbonless paper, and is a copying paper that develops color by mechanical or impact pressure, such as when writing, quipwriting, etc., and can make multiple copies at the same time. There are some called transfer type papers and some called single colored papers, but their coloring mechanism is based on a coloring reaction between an electron-donating colorless dye and an electron-accepting color developer (
It is something. 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, a colorless color-forming pressure-sensitive dye is dissolved in non-volatile oil to form a pressure-sensitive dye solution, which is then wrapped in a polymeric film such as gelatin, with a diameter of several microns to more than ten microns. Microcapsules 4 are applied.

The surfaces of the middle paper 2 and the bottom paper 30 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 copies, stack them in the order of 10-(middle)-(middle)-bottom (the dye-containing coated side and the developer-containing coated side face each other), and apply local pressure such as pen pressure 6 or typing pressure. When pressure is applied, the capsule 4 in that area
is broken and the pressure-sensitive dye solution is transferred to the color developer 5 to obtain a copy record.

As an electron-accepting color developer, il) USP 2.712
(2) Substituted phenols and diphenols disclosed in Japanese Patent Publication No. 40-9309, (3)
p-substituted phenol-formaldehyde polymer disclosed in Japanese Patent Publication No. 42-20144, (4) Japanese Patent Publication No. 49-1989
Aromatic carboxylic acid metal salts disclosed in Japanese Patent Publication No. 52-1327 and the like have been proposed, and some of them have been put into practical use.

Among the laminated structure of pressure-sensitive copying paper, the sheet coated with a color developer layer, that is, the color developer sheet, must have excellent color development that remains unchanged immediately after sheet manufacture and after long-term storage. Examples include less yellowing during storage and exposure to radiation such as sunlight, and the color image is robust and does not easily disappear or fade due to radiation, water, or plasticizers.

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 adsorb gases 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 low. p-phenylphenol-novolak resin, which is most commonly used as a p-substituted phenol-formaldehyde polymer, has excellent coloring properties, but the coated paper is exposed to sunlight or during storage (especially when exposed to nitrogen oxides in the air). ), and the colored image fades significantly. Furthermore, although aromatic carboxylic acid metal salts have good resistance to yellowing, their color development at low temperatures, resistance to water or plasticizers, and stability to light are still far from satisfactory.

[Problems to be Solved by the Invention] An object of the present invention is to provide a novel method for producing a polyvalent metal compound of salicylic acid resin useful as a color developer, which eliminates the above-mentioned drawbacks.

[Means for Solving the Problem] In order to achieve the above object, the present inventors developed an alkyl-substituted salicylic acid compound which is insufficient for practical use, and an aromatic compound which is superior to this compound but whose performance is desired to be further improved. The present invention was completed as a result of extensive research into salicylic acid compounds that have performance as a color developer superior to that of group-substituted salicylic acid compounds. That is, the present invention provides a salicylic acid ester represented by the general formula (1) (wherein R1 represents an alkyl group, an aralkyl group, an aryl group, or a cycloalkyl group having 1 to 12 carbon atoms). ,
R2 and R3 represent a hydrogen atom or a methyl group, and R4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ) is a method for producing a polyvalent metal compound of a salicylic acid resin, which is characterized by reacting a styrene derivative represented by the following formula, hydrolyzing the resulting salicylic acid ester resin, and then reacting the resulting salicylic acid ester resin with a polyvalent metal salt.

A color developer sheet using a new color developer made of a polyvalent metal compound of salicylic acid resin is equivalent to or better than a color developer sheet using an inorganic solid acid or p-phenylphenol novolak resin. Furthermore, it has improved resistance to yellowing due to sunlight irradiation, and in particular has significantly improved resistance to yellowing due to nitrogen oxides in the air, making it extremely advantageous in handling and storage.

On the other hand, when compared with metal salts of salicylic acid compounds, which are typical aromatic carboxylic acid metal salts, the disadvantages of conventionally known aromatic carboxylic acid metal salts as color developers are (a) colorless color development; This can improve the following problems: (b) the lack of compatibility with the non-volatile oil in which the coloring matter is dissolved; (c) the dissolution in water; (c) fading of the colored image by light; and (ii) the high cost. The color developer of the present invention has improved color development properties at low temperatures, stability of color images against light and water, etc., and makes it possible to solve the above-mentioned problems and supply a useful color developer at a low cost.

This polyvalent metallized salicylic acid resin of the present invention is produced by subjecting salicylic acid esters to a Friedel-Crach reaction with a styrene derivative in the presence of a strong acid catalyst (hereinafter referred to as the first-stage reaction).
, the obtained salicylic acid ester resin is hydrolyzed (hereinafter referred to as the second stage reaction 7), and the salicylic acid resin after hydrolysis is further reacted with a polyvalent metal salt (hereinafter referred to as the third stage reaction). do.

The salicylic acid resins produced in the first and second stages have never been disclosed in the past and were newly discovered by the present inventors.

This first stage reaction is a reaction in which a salicylic acid ester represented by the NB formula (I) is reacted with a styrene derivative represented by the general formula (II) in the presence of a strong acid catalyst to obtain a salicylic acid ester resin.

Conventionally, methods for obtaining various alkyl-substituted salicylic acids by alkylation of salicylic acid have been common, and several methods are known.

For example, by reacting salicylic acid with isobutanol, te
How to obtain rt-butylsalicylic acid ("Experimental Chemistry Course")
18@, p. 30 (1956), round neck), salicylic acid 1
2 moles of phenylethanol are reacted with 5-[α
-methyl-4°-(α-methylbenzyl)-benzyl]
- Method for obtaining salicylic acid, etc. (Ciba Gaiki Co., Ltd., JP-A-6
1-100493.62-96449), etc.

In addition, the present inventors first discovered a method of condensing salicylic acid and various benzyl compounds to obtain various co-condensed resins (Japanese Patent Application No. 61-262019.62-18472゜6).
2-19672.62-6218). However, all of these are reactions between salicylic acid and alcohols or alkoxy compounds. A method of directly reacting salicylic acid with an olefin compound is disclosed in JP-A-62-84045. However, in the above method, because the reactivity of salicylic acid having an electron-withdrawing group is low, a relatively large amount of an aromatic sulfonic acid compound is used as a catalyst and the reaction is carried out at high temperature to obtain 1 mole of the corresponding aromatic substituted salicylic acid. However, under such extreme conditions, the styrene derivative used tends to polymerize, and there are also difficulties in controlling the reaction heat. Furthermore, only two types of dibenzyl salicylic acid have been obtained from this aromatic substituted salicylic acid compound, but this is because the reactivity of salicylic acid is similarly low. By increasing the amount of resin, it cannot be expected to improve the color development property or improve the stability against light and water. In response to the low reactivity of salicylic acid as described above, the present inventors have surprisingly found that when a styrene derivative is reacted with a salicylic acid ester, the styrene derivative easily reacts with the benzene ring of the salicylic acid ester under mild conditions. I discovered that.

That is, when the present inventors sequentially reacted salicylic acid esters with styrene derivatives in the presence of a strong acid catalyst, the α-position of the styrene derivative reacted to the ortho-position and/or para-position with respect to the hydroxyl group of the salicylic acid skeleton, and further It was found that excess styrene reacts with the benzene ring of the styrene derivative bonded to the salicylic acid skeleton, resulting in an increase in molecular weight. The result is a useful novel salicylate resin as described above. The salicylic acid esters used in this first stage reaction include methyl salicylate,
Ethyl salicylate, 〇-propyl salicylate, isopropyl salicylate, 〇-butyl salidylate, izbudel salicylate, tert-butyl salidylate, isoamyl salicylate, tert salicylate, -del salidylate, →no-lycylic acid Examples include, but are not limited to, nonyl, dodecyl salicylate, cyclohexyl salicylate, phenyl salicylate, pencil salicylate, α-methylbenzyl salicylate, etc. Industrially preferred is methyl salicylate, which is inexpensive. .

Next, the styrene derivatives defined by the general formula (II) used in this reaction include styrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene,
0-ethylstyrene, p-ethylstyrene, 0-isopropylstyrene, m-isopropylstyrene, p-isopropylstyrene, p-tert-butylstyrene, α
Examples include, but are not limited to, -methylstyrene and β-methylstyrene. Industrially preferred is styrene, which is inexpensive.

The amount of the styrene derivative used is 1 to 20 molar ratio, preferably 2 to 10 molar ratio to the salicylic acid ester. If the amount of styrene derivative used is less than the scope of the present invention, compatibility with the non-volatile oil in the microcapsules of the upper paper or insolubility in water may be used; color ratio decreases, and the color density does not reach the desired level. The weight average molecular weight of the salicylic acid ester resin produced within this range of usage is 500 to 10.
,000.

A strong acid catalyst is used in this first stage reaction.

For example, mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, ferric chloride,
A free sol fluorocarbon catalyst such as zinc chloride, aluminum chloride, stannic chloride, titanium tetrachloride, boron trifluoride, or a strong acid catalyst such as methanesulfonic acid or trifluoromethanesulfonic acid can be used. Among these, particularly preferred is sulfuric acid, which is inexpensive. The amount of catalyst used is 0.05 to 200% based on the total weight of salicylic acid esters and styrene derivatives.
It is preferably in the range of 1 to 50% by weight considering economic efficiency.

Further, a solvent may be used in this first stage reaction. Examples of solvents that are inert to the reaction include aliphatic hydrocarbons such as n-hexadi, n-hebutane, n-pentane, and cyclohexane, ethers such as ethyl ether and ethylene glycol dimethyl ether, and ethyl acetate. ,
Esters such as butyl acetate, methylene chloride, 1.2-dichloroethane, 1.1.2-1~lichloroethane, halogenated hydrocarbon solvents such as carbon tetrachloride, chloroform, monochlorobenzene, organic acids such as acetic acid, propionic acid, etc. acids,
Ketones such as acetone and methyl ethyl ketone, their compounds, benzene, carbon disulfide, nitromethane, acetonitrile,
Examples include tetrahydrofuran.

The amount of these solvents to be used is desirably 30 (volume/weight) times or less relative to the total weight of the reaction raw materials, considering economic efficiency.

The reaction temperature when carrying out the first stage method is -20 °C to 1
80°C, preferably in the range of 0-120°C. Reaction time is 1 to 30 hours.

In the first stage reaction, the general method is to prepare a solution of salicylic acid esters in a solvent, charge the catalyst, and react while dropping the other raw material, a styrene derivative, at a predetermined temperature. At this time, the dropping time is preferably 50% or more of the total reaction time, and the usual dropping time is 1 to 20 hours. After the reaction, if the solvent used is insoluble in water, the resin may be obtained by adding water and washing and separating the two layers, and then distilling off the solvent. If the solvent is soluble in water, the resin may be obtained. It can be obtained by charging the resin and precipitating the resin.

As a method for hydrolyzing the salicylic acid ester resin obtained in the first stage reaction (second stage reaction), a conventional method using an acid or alkaline aqueous solution is used. That is, in hydrolysis with acids, mineral acids such as hydrochloric acid and sulfuric acid, a combination of mineral acids and organic acids such as sulfuric acid and acetic acid, benzenesulfonic acid, p-
Organic sulfonic acids such as toluenesulfonic acid, tetralobenzenesulfonic acid, methanesulfonic acid, Lewis acids such as aluminum chloride, zinc chloride, and tin chloride, as well as trifluoromethanesulfonic acid, Nafion H (D
It is carried out using a super strong acid such as U' Pont (trade name) and water. For hydrolysis with alkali, a common method is to mix caustic soda, caustic potassium and water.

When carrying out the hydrolysis reaction using these acids or alkalis, the ratio of acid or alkali to water can be selected at any desired ratio, but is usually 1.100 to 99:1, preferably 5:95.
-955 (weight ratio).

In addition, the amount of acid or alkali to be used with respect to the salicylic acid ester resin obtained in the first stage reaction can be carried out in any ratio in the case of acid, but it is usually 0.05 to 0.05 depending on the strength of the acid.
This is done in a 30-fold molar range. In the case of an alkali, the amount is in the range of at least equivalent to 30 times the molar amount of the salicylic acid ester as the raw material.

The reaction temperature is in the range of 50 to 200°C, preferably 80 to
The range is 60°C. When conducting at high temperatures, it is carried out in an autoclave under naturally occurring pressure, but the pressure range is 1.
~30 atm. Reaction times range from 1 to 50 hours. quaternary ammonium salt for the purpose of shortening the reaction time,
Phase transfer catalysts such as quaternary phosphonium salts, crown ethers, cributates, and polyethylene glycols may be added as reaction promoters.

Further, although this reaction is usually carried out without using an organic solvent, an organic solvent may be used. This solvent is N-
methylformamide, N,N-dimethylformamide,
Aprotic polar solvents such as N,N-dimethylacetamide, dimethylsulfoxide, sulfolane, 1,3-dimethyl-2-imidazolidinone, N-methylpyrrolidone, hexamethylphosphotriamide, ethylene glycol,
Glycols such as polyethylene glycol dialkyl ether, 2-methoxyethanol, and 2-ethoxyethanol can be used, and solvents that are immiscible with water such as toluene, xylene, monochlorobenzene, 1,2-dichloroethane, and 1.1.2-trichloroethane can be used. can also be used.

The amount of this solvent to be used is 0.5 to 10 times (volume/weight) the amount of the raw material.

After the completion of the reaction, the desired product can be obtained from the reaction solution using conventional methods such as liquid separation, dilution, concentration, etc. to obtain a hydrolyzate of the salicylic acid ester resin, ie, a salicylic acid resin.

Several known means can be applied to produce a metal compound from the salicylic acid resin thus produced in the third stage reaction. For example, it can be produced by reacting both the alkali metal salt and the water-soluble polyvalent metal salt of the salicylic acid resin in water or a solvent in which both are soluble. That is, by reacting an alkali metal hydroxide, carbonate, alkoxide, etc. with the resin, an aqueous solution of the alkali metal salt of the resin,
This is a method in which an alcohol solution or a water-alcohol mixed solution is obtained, and then a water-soluble polyvalent metal salt is reacted. It is desirable to react about 0.5 to 1 gram equivalent of water-soluble polyvalent metal salt per mole of salidylic acid. In addition, a salicylic acid resin polyvalent metal compound can be obtained by mixing salicylic acid 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. Can be manufactured. Optionally, further basic substances, such as ammonium carbonate,
Ammonium bicarbonate, ammonium acetate, and ammonium benzoate may be added and heated to cause a melting reaction.

Furthermore, salicylic acid resin and polyvalent metal carbonates, oxides,
Using hydroxide, heat melt reaction with basic substances such as ammonium formate, ammonium acetate, ammonium caproate, ammonium stearate, ammonium benzoate and other organic carboxylates, and then cool to resin salicylic acid polyvalent metal Chemicals can be manufactured.

When producing a metallized salicylic acid resin by heating and melting, the reaction temperature is usually 100 to 180°C, and the reaction time is 1 to several hours, depending on the resin composition, reaction temperature, type of polyvalent metal salt, and amount used. That's about it. The polyvalent metal salt may be an organic carboxylate, carbonate, oxide, or/and hydroxide of a polyvalent metal such that the metal is present in an amount of 1 to about 20% by weight based on the total weight of the resulting resin metallized product. It is preferable to use objects.

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

The softening point (ring and ball softening point measuring method according to JIS-2548) of the polyvalent metal compound of salicylic acid resin produced by this heat-melting method is 50 to 120°C.

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

The polyvalent metallized salicylic acid resin obtained by the method described below has excellent properties as a color developer. In order to use the metallized product as a color developer, it is preferable to grind it with a sand grinding mill or the like to obtain a suitable particle size. For actual use, the color developer may be further suspended or dissolved in a solvent and used in the desired form. It is also possible to use it in combination with organic polymers such as phenol-formaldehyde resins or metal salts of aromatic carboxylic acids, and in addition, the group consisting of zinc, magnesium, aluminum, lead, titanium, calcium, Kobal 1~, nickel, manganese, and barium. At least one of polyvalent metal oxides, hydroxides, and carbonates selected from the following may be used in combination.

The method for preparing color developer sheet 1- for pressure-sensitive copying paper using the color developer of the present invention includes (1) preparing a water-based paint using an aqueous suspension of the metal compound and applying it to a support such as paper; how to,(
2) A method in which the metallized product is strained during paper making, and (3) A method in which a paint is prepared using a solution or suspension of the metallized material in an organic solvent and applied to a support can be used.

To form a color developer layer on a support such as paper by coating,
It is desirable that the color developer has appropriate viscosity and coating suitability, and it can be made into an aqueous suspension as in (1) and (2) above, or dissolved or suspended in a solvent and then further added to kaolin clay. It is used as a paint by blending with other ingredients, such as calcium carbonate, starch, synthetic or natural latex, etc., to adjust the viscosity and coating suitability to an appropriate level.

The proportion of the color developer component in the paint is preferably 10 to 70% of the total solid content, and the proportion of the color developer component is 10%.
If it is less than 70%, sufficient color development cannot be achieved, and if it exceeds 70%, the paper surface properties of the color developing sheet deteriorate. The amount of paint applied is 0.5 g/m'' or more in terms of dry weight, preferably 1 to 10 g.
/rd.

The color developing sheet using the novel polyvalent metallized salicylic acid resin obtained by the present invention has the same or better coloring property than the color developing sheet using an inorganic solid acid or p-phenylphenol novolak resin. Furthermore, yellowing caused by sunlight exposure is also improved, and in particular, resistance to yellowing caused by nitrogen oxides in the air is greatly improved, making it extremely advantageous in handling and storage.

On the other hand, when compared with metal salts of typical salicylic acid compounds as metal salts of aromatic carboxylic acids, their color development at low temperatures, stability with light, and resistance to water are significantly lower. do. In addition, it is extremely advantageous because it can be manufactured using inexpensive raw materials and in a simple process.

[Example] Hereinafter, the present invention will be explained in detail with reference to Examples.

The preparation of a pressure-sensitive copying paper color developer sheet using the products obtained in each of the Examples and Comparative Examples as a color developer and the method for measuring the performance of the color developer sheet will be described below. The performance measurement results are collectively shown in Table 1.

1. Preparation of Color Developer Sheet Using the salicylic acid resin metallization obtained in Examples 1 to 7 and the compound of Comparative Example 1.2 as color developers, the following composition was dispersed with a sand grinding mill and suspended. A suspension was prepared.

Color developer 6 parts by weight Polyvinyl alcohol (Clara #117) 10% aqueous solution
3 parts by weight water 22.
5 parts by weight Next, a paint having the following composition was prepared using the suspension.

Suspension 10 parts by weight Light calcium carbonate 10 parts by weight Source Powder
08 parts by weight synthetic rubber latex
08 parts by weight water 32.
5 parts by weight of these paints on high-quality paper with a dry coating amount of 5.0 parts by weight.
It was coated and dried to give a color developing sheet of ~5.5 g/m''.

2 Color development speed and density (5°C, 60%RH and 20%
℃, 65% rule (conducted in a constant temperature and humidity chamber) Using commercially available blue coloring paper (NW-407 manufactured by Jujo Paper Industries) containing crystal violet lactone (CVL) as the main pressure-sensitive dye,
The two coated surfaces of the color developing sheet (lower paper) coated with water-based paint are placed on top of each other, facing each other, and the color is developed by pressing with an electronic typewriter.

The color is measured at two points, 1 minute and 30 seconds after stamping and 24 hours later, and displayed as a Y value.

3. Light fastness of color image The color developing sheet developed using method 2 was exposed to a carbon arc fade meter (manufactured by Suga Test Instruments) for 2 hours (and 4 hours), and the reflectance after irradiation was measured using a Σ-80 color difference meter. It was measured using a Y value and expressed as a Y value.

The lower the Y value (and the smaller the difference from the pre-test value, the less fading caused by light, which is preferable).

4 Prepare melamine-formaldehyde resin membrane microcapsules with an average particle size of 5.0 LL containing plasticizer-resistant thiocdylphthalate (DOPI) as the core material, add a small amount of liquid starch binder to make a coating liquid, and coat with an air knife coater. DOP microcapsule-coated paper is prepared by coating and drying the dry coating amount on paper to a dry coating amount of 5 g/rr+''. After facing the DOP microcapsule-coated paper and the color-developing side of the color-developing sheet, 100 kg is coated. The DOP is passed through a super calender roll having a linear pressure of /Cm to uniformly infiltrate the coloring surface.

The reflectance after 1 hour is measured using a Σ-80 color difference meter and expressed as a Y value. 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 Image The color developing sheet developed by method 2 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 developer sheet f6-11 Yellowing due to NO
2 (sodium nitrite) and H, (PO2 (phosphoric acid)) in a closed container with NOx gas atmosphere generated by the reaction.
Store for a while and check the degree of yellowing.

After storage, the WB value is displayed using a Σ-80 color difference meter for one hour. The larger the WB value and the smaller the difference from the WB value of a sheet that has not been exposed to NOx gas (indicated as untested sheet in Table 1), the less yellowing under the NOx atmosphere.

(6-, l) Irradiate the color developing sheet that yellows with light for 4 hours using a carbon arc fade meter (manufactured by Suga Test Instruments), and display the WB value using a Σ-80 color difference meter after irradiation. The smaller the difference from the WB value of the irradiated sheet (indicated as untested sheet in Table 1), the smaller the yellowing caused by light irradiation.

Example 1 Methyl salicylate 15.2 g (0.1 mol), 1
．． 2-dichloroethane 50++1! , 96% concentrated sulfuric acid3.
75 g was placed in a glass reactor, and 52 g (0.5 mol) of styrene was added dropwise 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. 50 mρ of acetic acid was added to the mixture, and a hydrolysis reaction was carried out under reflux for 18 hours. After the reaction was completed, the reaction solution was poured into 300 mj2 of water, and when it was left to stand, a brown resin precipitated.

Tilt this, discard the upper layer of water, and add 300 mJ2 of warm water.
Washed twice with

The weight average molecular weight of the resulting salicylic acid resin was 960. This resin was placed in another reactor and the temperature was 150-16
At 0°C, a mixture of 6.3 g of zinc benzoate and 10 g of ammonium bicarbonate 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 pulverized to obtain 79.5 g of zinc benzoate modified salicylic acid resin. The softening point of this product was measured using a ring and ball softening point measuring device according to JIS-2548 and found to be 82°C.

Example 2 22.8 g (0.1 mol) of benzyl salicylate, 75 nl of styrene chloride, and 159 g of 96% concentrated sulfuric acid were charged into a glass reactor, and 83.2 g (0.8 mol) of styrene was added at a temperature of 5 to 12°C. The mixture was added dropwise over 5 hours to react.

After aging at the same temperature for 3 hours, the mixture was neutralized with dilute ammonia water and separated to obtain a methylene chloride solution of salicylic acid ester resin. The weight average molecular weight of this resin was 1,380. Next, the solvent is distilled off while heating the solution,
The temperature was raised to 120°C. Add 35 g of 20% zinc chloride aqueous solution to the slightly viscous salicylic acid ester resin (0.05
mol) was added dropwise, and the mixture was stirred at reflux for 12 hours. Thereafter, the temperature was raised and the mixture was stirred at a temperature of 140° C. for 2 hours, and then toluene 250+nj2 was added. Next, the temperature is 70-80°
7.3g of 28% ammonia water (0,
12 mol) was added dropwise and stirred for 1 hour.

Then, the mixture was allowed to stand still and the lower aqueous layer was separated and removed, and then the temperature was raised to distill off toluene. The reddish-brown tree sap was drained, cooled, and then crushed to produce zinc-modified salicylic acid resin 93.
．． 5 g was obtained. The softening point of this material was 76°C.

Example 3 The same reaction as in Example 1 was carried out except that 38.4 g (0.3 mol) of p-methylstyrene was used instead of styrene. Next, 80 g (0.2 mol) of a 10% caustic Sogoo aqueous solution was added to this reaction solution, and the temperature was raised to distill off the solvent. Then, a hydrolysis reaction was carried out at a temperature of 100 to 102°C for 12 hours.

The reaction solution is a slightly cloudy solution, and 88% of water is added to it.
After diluting with 50 mff, 400 g (0.07 mol) of 5% zinc sulfate aqueous solution was added at a temperature of 20 to 25 °C for 3 hours.
It dripped over time. The deposited 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.

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

Example 5 Methyl salicylate 15.2 g (0.1 mol), 1.2
-50 nl of dichloroethane! , 3.75g of 96% concentrated sulfuric acid
was placed in a glass reactor, and 83.2 g (0.8 mol) of styrene was added dropwise over 12 hours at 0 to 5° C. while stirring vigorously. Thereafter, aging was performed for 3 hours at the same temperature to complete the first stage reaction. Next, add 15 ml of water to the second reaction solution.
mj2 was added dropwise, heated to 104℃, and the solvent
．． 2-dichloroethane was distilled off. 18 g of a 45% caustic sorter aqueous solution was added dropwise to this, and a second stage reaction was carried out at a temperature of 95 to 100°C for 2 hours. After the second stage reaction was completed, the reactor was cooled to 80°C, and 150 nl of toluene was charged therein. Subsequently, the mixture was neutralized with a 10% aqueous sulfuric acid solution until the pH reached 6, and then the lower aqueous layer was removed by liquid separation.

Further, 60 g of 20% saline was added and washed with stirring, and then the lower layer was separated. 2 g of magnesium oxide was added to the obtained toluene solution of the salicylic acid resin, and the third stage reaction was carried out while heating and raising the temperature to distill off toluene. Finally 145~
After being kept under aspirator vacuum at a temperature of 150° C. for 30 minutes, it was discharged into a porcelain dish to obtain a reddish-brown transparent magnesium modified salicylic acid resin (yield: 94.3 g). The softening point was 93°C and the average molecular weight was 1150.

Example 6 The method of Example 5 was repeated except that 2 g of zinc oxide and 6.2 g of nickel acetate tetrahydrate were used instead of magnesium oxide in the third stage reaction, and zinc, salicylic acid resin,
A nickel modified product was obtained (yield: 96.5 g). Softening point is 1
At 05°C, the average molecular weight was 1350.

Example 7 20.4 g (0.1 mol) of isobutyl salicylate, 25 nu of acetic acid, and 1.5 g of trifluoromethanesulfonic acid as a catalyst were charged into a glass reactor, and the temperature was 25 to 35 ml.
52 g (0.5 mol) of styrene were added dropwise over a period of 5 hours at °C. After that, it was aged for 3 hours at the same temperature.
The stage reaction was completed. Next, this reaction solution was transferred to an autoclave, 10 g of water was further added, and the temperature was increased. Hydrolysis reaction was carried out at a reaction temperature of 150 to 160° C. and a pressure of 3 to 5 atm for 15 hours to complete the second stage reaction. When this was cooled and diluted with 300 n of water + J2, a brown viscous resinous substance precipitated. Separate this, put it in a glass reactor, add 8g of zinc hydroxide, and adjust the temperature to 145°.
Raised it to C. Further, volatile components were removed under vacuum for 30 minutes to complete the third stage reaction. The yield of the zinc-modified salicylic acid resin was 45.8 g, the softening point was 68°C, and the average molecular weight was 580.

Comparative Example 1 170 g of p-phenylphenol, 22.5 g of 80% paraformaldehyde, 2°O of p-toluenesulfonic acid
g and 200 g of benzene were charged into a glass reactor,
The reaction is carried out at 70 to 80° C. for 2 hours while stirring and heating to distill water produced by the reaction out of the system by azeotropy with benzene. After reaction 10% sodium hydroxide aqueous solution 32
0 g was added, and benzene was distilled off by steam distillation. Next, after cooling, dilute sulfuric acid was added dropwise, and the precipitated p-phenylphenol formaldehyde polymer was collected by filtration, washed with water, and dried to obtain 176 g of white powder.

Comparative Example 2 9.4 g of phenol and 0.2 g of sulfuric acid are placed in a reactor equipped with a thermometer, reflux condenser, dropping funnel and stirring device. Next, while stirring, 23.6 g of α-methylstyrene was added dropwise using a dropping funnel at a temperature of 50° C. over 5 hours. After the addition was completed, the mixture was aged for 5 hours and then poured into a dilute aqueous sodium carbonate solution. The liquid was separated to obtain an oil layer, which was vacuum distilled.

At a vacuum degree of 3 to 4 mm and 1 g, 22 g of a fraction of 220° C. or higher was obtained. Next, add 7.5 g of a 40% caustic sorter aqueous solution to this fraction.
was added, and dehydration was performed under reflux of xylene. After dehydration,
The xylene mixture was transferred to an autoclave, and then carbon dioxide gas was introduced at a temperature of 160° C. to a concentration of 30 kg/cm 2 . Thereafter, the reaction was carried out at the same temperature for 5 hours. After the reaction,
After cooling and purging residual gas, the reaction solution was extracted with hot water and neutralized with dilute sulfuric acid, resulting in precipitation of crystals. Filter this out,
Recrystallization from an acetic acid aqueous solution gave 8 g of 3,5-di(a,α-dimethylbenzyl)salicylic acid. A zinc salt was produced from this salicylic acid compound in the same manner as in Example 2.

[Effects of the Invention] The polyvalent metallized salicylic acid resin of the present invention can be prepared using inexpensive raw materials and through simple work steps. Color developer sheets for pressure-sensitive copying paper using this method require less color developer components and less paint, and the concentration, viscosity, etc. of the paint can be changed over a relatively wide range, allowing for on-machine coating. This makes it possible to perform both off-machine and off-machine coating, which brings great benefits to the pressure-sensitive paper manufacturing process.

The color developing sheet of the present invention does not cause yellowing due to light or gases such as nitrogen oxides in the air, has a stable color image against light and plasticizers, does not cause a decrease in color density, and is water resistant. Since it also has good properties, it has become possible to expand its use to applications for which conventional products were unsuitable because long-term storage stability is required, and its practical significance is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the structure of pressure-sensitive copying paper. ■...-Bottom paper 2...Middle paper 3...Bottom paper 4...Microcapsule 5...Color developer diagram 1

Claims (1)

[Claims] (1) General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (In the formula, R_1 represents an alkyl group, an aralkyl group, an aryl group, or a cycloalkyl group having 1 to 12 carbon atoms) Salicylic acid esters include the general formula (II) ▲Mathematical formulas, chemical formulas, tables, etc.▼(II) 1. A method for producing a polyvalent metal compound of a salicylic acid resin, which comprises reacting a styrene derivative represented by (representing an alkyl group), hydrolyzing the obtained salicylic acid ester resin, and then reacting the resulting salicylic acid ester resin with a polyvalent metal salt.