JP2624529B2 - Color developer - Google Patents

Description

The present invention relates to a developer. More specifically, the present invention relates to a recording material, particularly a developer for a pressure-sensitive recording material.

[Prior Art] An electron-accepting color developer causes a remarkable optical change upon contact with an electron-donating colorless dye, and is widely used in recording materials. As the color developing agents used in these, inorganic clay minerals and organic substituted phenol-formaldehyde condensation polymers or substituted polyvalent metal salts of salicylic acid are known. (US Patent No. 2712507
Nos. JP-A-51-25174, JP-A-62-19486, and JP-A-62-176875
[Problems to be Solved by the Invention] An organic color developer, that is, a polyvalent metal salt of a substituted phenol-formaldehyde polycondensate and a substituted salicylic acid is an inorganic type developer. Since the recorded image is clearer and more stable than the colorant, it has already been widely used. However, among these, the decomposing action by microorganisms such as paratertiary octylphenol-formaldehyde condensation polymer, paranonylphenol-formaldehyde condensation polymer or zinc 3,5-ditert-butylsalicylate is slow, and the There are some problems with the disposal of chemicals.

[Means for Solving the Problems] If the organic color developer is rapidly decomposed by microorganisms, the discarded color developer is immediately lost from the environment, which is the most desirable place.

Microbial degradation studies show that substituted salicylic acid and its polyvalent metal salts are rapidly degraded by microorganisms if the substituted salicylic acid substituents are limited to methyl, ethyl, isopropyl or secondary alkyl groups. did.

According to the invention, the compounds of the general formula [I] (Where R ₁ represents a methyl group, an ethyl group, an isopropyl group or a secondary alkyl group, R ₂ represents a hydrogen atom, a methyl group, an ethyl group, an isopropyl group or a secondary alkyl group, R ₃ represents a methyl group, and R ₁ , color developer for record material mainly containing zinc salt of substituted salicylic acid represented by the total number of carbon atoms of R ₂ and R ₃ is 9 Nashii 16) is provided.

The developer of the present invention is rapidly decomposed by microorganisms, and the obtained recorded image is extremely clear and stable to moisture, heat, light or environmental gas, and has sufficient practicality.

In the general formula [I], R ₁ represents a methyl group, an ethyl group, an isopropyl group or a secondary alkyl group, R ₂ represents a hydrogen atom, a methyl group, an ethyl group, an isopropyl group or a secondary alkyl group, and R ₃ represents a methyl group; The total number of carbon atoms of ₁ , R ₂ and R ₃ is 9 to 16.

The secondary alkyl group has the general formula [II] (Here, R 'and R "represent an alkyl group, provided that R' and R" are not both methyl groups.) According to this definition, for example, a secondary butyl group is the only group in which R 'is a methyl group and R "is an ethyl group. However, a secondary pentyl group is a group in which R' is a methyl group and R" is a methyl group. A pentan-2-yl group which is a normal propyl group, a 2-methylbutan-3-yl group wherein R 'is a methyl group, R "is an isopropyl group, and pentane-3-yl wherein both R' and R" are ethyl groups
Includes three groups, yl groups. Then, when the number of carbon atoms constituting the secondary alkyl group further increases, the type of the isomer further increases. However, most of the secondary alkyl groups derived from industrially easily available materials are linear in R 'and R ", and the number of isomers is also limited. The carbon number of the secondary alkyl group is Preferably it is 4-12.

Preferred materials for introducing these secondary alkyl groups into the salicylic acid nucleus include chlorinated paraffins and alkylenes, especially ethylene polymers such as butene, hexene, octene, decene, dodecene, tetradecene or hexadecene. It is easily obtained on an industrial scale. Representative secondary alkyl groups introduced by these materials include secondary butyl, pentan-2-yl, pentan-3-yl, hexane-2-yl, hexane-3-yl, and octane. -2-yl group, octane-3-yl group, octane-4-
Yl group, decane-2-yl group, decane-3-yl group, decane-4-yl group, decane-5-yl group, dodecane-2
-Yl group, dodecane-3-yl group, dodecane-4-yl group, dodecane-5-yl group or dodecane-6-yl group.

In order to introduce these substituents into salicylic acid, chlorinated paraffins or alkylenes are allowed to act on m-cresol in the presence of a catalyst to introduce the substituents, and then to the alkyl metal salt of the product (substituted phenol). This is a method in which carbon dioxide is added to derive a substituted salicylic acid. As the catalyst, boron trifluoride, Lewis acid such as aluminum chloride or ferric chloride, methanesulfonic acid, organic acid such as trifluoromethanesulfonic acid or paratoluenesulfonic acid,
Alternatively, an acidic catalyst containing an inorganic acid such as sulfuric acid, perchloric acid, phosphoric acid, acid clay or heteropoly acid; and an aluminum salt of m-cresol. In particular, in an aluminum salt of m-cresol, a secondary alkyl group can be selectively introduced at the ortho-position to the hydroxyl group of m-cresol. When secondary alkylation of phenols or salicylic acids with alkylenes using an acidic catalyst, the product is known to contain many isomers.
For example, m- in the presence of trifluoromethanesulfonic acid
If cresol is alkylated with 1-octene, the products will be 2- (octan-2-yl) -4-methylphenol, 2- (octan-3-yl) -5-methylphenol and 2- (octane-4). -Yl) -5-methylphenol. As a result, 3-
Secondary octyl-6-methylsalicylic acid contains three isomers corresponding to substituted phenols, such as 3- (octan-2-yl) -6-methylsalicylic acid.

The total number of carbon atoms of R ₁ , R ₂ and R ₃ is 9 to 16. When the total number of carbon atoms is less than 9, the developer has poor water resistance or moisture resistance, and when it exceeds 16, the decomposability of the developer by microorganisms is extremely slow.

A preferred substituted salicylic acid for the purpose of the present invention is 3-
Secondary octyl-6-methylsalicylic acid, 3-secondary octyl-5,6-dimethylsalicylic acid, 3-secondary decyl-6-methylsalicylic acid, 3-secondary dodecyl-6-methylsalicylic acid, and the like. It was confirmed that all of these substituted salicylic acids were easily decomposed by microorganisms.

The zinc salt of a nuclear-substituted salicylic acid can be obtained as a water-insoluble salt by a metathesis reaction between an aqueous solution of a corresponding alkali metal salt of a nuclear-substituted salicylic acid and an aqueous solution of a water-soluble zinc compound. These are usually resinous substances having a low softening point but very high in the vicinity of room temperature, and it is very difficult to handle them as they are. Heating in water makes it easier to flow by heating, or if an organic solvent is added, the viscosity is reduced and handling becomes easier. Also, preferably, if an organic solvent is previously allowed to coexist at the time of the metathesis reaction, the zinc salt of the nucleus-substituted salicylic acid generated by the reaction is immediately dissolved in the organic solvent and the viscosity is reduced, so that the reaction is smooth even at a low temperature. Since the target compound after metathesis must be separated from the aqueous layer as an oily layer, the organic solvent preferably has a low solubility in water, and a solvent having a solubility in water of 10% by weight or less is used. Since the used organic solvent must be removed eventually, a solvent having a too high boiling point is not preferable, and one having a boiling point in the range of 60 ° C to 180 ° C is used. Preferred specific examples thereof are benzene, toluene, xylene, ethylbenzene, chloroform, carbon tetrachloride, ethylene chloride, vinylidene chloride, 1,2-dichloroethylene, butanol, amyl alcohol, isopropyl ether, butyl ether, methyl ethyl ketone, methyl propyl ketone, Examples include methyl isobutyl ketone or ethyl acetate. Usually, 0.05 to 5 parts by weight to 1 part by weight of the zinc salt of the nuclear-substituted salicylic acid is used.
Parts by weight are used.

Since the zinc salt of the nuclear-substituted salicylic acid according to the present invention is slightly hydrated in water and its softening point is reduced by 50 ° C. to 80 ° C., it is usually used in the preparation of other organic developers. Not very suitable for pulverization and dispersion in water. If you dare to take such a method, take measures such as pulverizing and dispersing at a very constant temperature, mixing with a resinous substance having a high softening point, and adding inorganic substances with a large surface area as grinding aids. Must take.

In order to finely disperse the zinc salt of the nuclear-substituted salicylic acid according to the present invention, it is preferable to liquefy and emulsify and disperse in water containing a dispersant by heating or adding an organic solvent. This organic solvent can be exactly the same as that used in the metathesis reaction, and if the metathesis product contains a solvent, the dispersion step can be carried out without adding a new solvent. The organic solvent can be removed azeotropically with water, if necessary, after emulsification and dispersion. As the emulsification dispersion medium used here, an ultrasonic homogenizer, a high-compression homogenizer, a homomixer, a sand grinder, or the like is preferable.

Examples of the dispersant used include sodium alkyl sulfate, sodium alkyl sulfonate, sodium alkyl aryl sulfonate, sodium salt of sulfosuccinate, sodium polyaryl polysulfonate, sodium polyacrylate, sodium polymethacrylate, and maleic acid. Examples thereof include a sodium salt of a polymer, polyvinyl alcohol, polyacrylamide, an acrylamide copolymer, and hydroxyethyl cellulose.

Metal oxides, metal hydroxides, metal carbonates, high molecular compounds, polymer compounds, dispersants, antioxidants, ultraviolet rays before and after dispersion for the purpose of increasing the value of the zinc-substituted salicylic acid as a color developer An absorbent or a developer can be mixed.

When a zinc salt of a nuclear-substituted salicylic acid is used as a color developer in a pressure-sensitive recording paper, a paint is prepared by dissolving it in an organic solvent or dispersing it in water, and applying and fixing it on a substrate. Is common. The paint may further contain inorganic pigments, viscous minerals, dispersants, adhesives, thickeners, defoamers, antioxidants, ultraviolet absorbers, bleaching agents, lubricants, or organic solvents, depending on the purpose. Can be.

Next, in order to further clarify the present invention, specific examples will be described.

Example 1 A five-necked flask having an inner volume of 5,000 ml is charged with 3,024 g (28 mol) of meta-cresol and 20 g of small granular aluminum. The flask is heated while blowing nitrogen gas to dissolve the aluminum. 150 ℃ of contents
After cooling to room temperature, the contents are transferred to a 10,000 ml stainless steel autoclave and the temperature is increased. When the temperature of the contents reaches 240 ° C, keep this temperature
-Inject 2,016 grams (18 moles) of octene in about 8 hours. After the press-in, the temperature is maintained for another 4 hours, and then the content is cooled. This was transferred to a 10,000 ml hard glass separating funnel, and 1,000 grams of toluene and 3
Wash with 800 ml of the specified hydrochloric acid. Hot water 8
Wash twice with 00 ml. The oil layer was transferred to a vacuum distillation apparatus, and the temperature at the top of the distillation tower was raised from 105 ° C under a vacuum of 1.2 torr.
Collect the distillate up to 110 ° C to get about 3,200 grams. Analysis by gas chromatography equipped with a capillary column revealed that it consisted of 2- (octen-2-yl) -5-methylphenol and small amounts of other isomers. Further, the hydroxyl value was 253.6 (theoretical value; 254.6), and it was confirmed that the compound was 2-secondary octyl-5-methylphenol.

Example 1-2 The 2-secondary secondary glass obtained in Example 1 was placed in a 1,000 ml hard glass three-necked flask equipped with a stirrer, a thermometer, and a device capable of azeotropically separating and removing water. 440 grams of octyl-5-methylphenol (2
Mol), 200 grams of toluene, 200 grams of diethylene glycol dimethyl ether and 157 grams (1.96 moles) of a 50 percent aqueous sodium hydroxide solution. Heat the flask with stirring to remove water azeotropically. After confirming complete removal of water, transfer the entire contents to a 1,000 ml stainless steel autoclave. Pressure 15 carbon dioxide into autoclave
Blow at kg / cm ² and react at 170 ° C until the absorption of carbon dioxide disappears. The reaction is completed in about one hour. Reduce the temperature of the contents to 60 ° C. and pour into 6,000 ml of water. Charge the previous aqueous solution and 1,000 g of toluene into a 10,000 ml hard glass four-necked flask equipped with a stirrer, thermometer, reflux condenser and spare port,
Heat the flask with stirring to boil the contents slightly. Stop heating and stirring, let the flask stand still, and remove the upper toluene layer from the preliminary port. Add 500 grams of toluene again, stir for 10 minutes, then let the flask stand still and remove the upper toluene layer. Such a washing operation is repeated five times. After switching the reflux condenser to the distillation port, the flask is heated to remove toluene azeotropically solubilized with water. Install a dropping funnel in the spare port,
600 grams of percent dilute sulfuric acid is added dropwise with vigorous stirring of the contents. If the mixture is stirred vigorously for another 20 minutes after the completion of the dropwise addition and allowed to stand, a light brown viscous liquid is released. After removing the aqueous layer, add 1,000 ml of water and heat the flask while stirring vigorously to boil the contents a little,
After standing still, remove the aqueous layer. Such a washing operation is performed 3 times.
Repeat. The light brown viscous liquid is transferred to a hard glass vacuum distillation apparatus with a volume of 1,000 ml and the volatile components are removed under a vacuum of 1.2 torr until the temperature of the kettle reaches 120 ° C. 476 g of the product after dehydration is a viscous light brown transparent liquid having an acid value of 210 (theoretical value: 212.2), which is confirmed to be 3-secondary octyl-6-methylsalicylic acid. .

Example 1-3 2,000 g of water containing 60 g of sodium hydroxide was charged into a hard glass beaker having an internal volume of 3,000 ml, and the 3-secondary octyl-6 obtained in Example 1-2 was stirred while stirring the contents. Slowly add methyl salicylic acid. 398 grams of 3-secondary octyl-6-methylsalicylic acid are required before the pH reaches 7. It is clear that this solution is an aqueous solution of sodium 3-secondary octyl-6-methylsalicylate, and it is a complete single peak even by analysis by liquid chromatography.
A 5,000 ml hard glass four-necked flask equipped with a stirrer, thermometer, reflux condenser, and dropping funnel was charged with 1,800 g of an aqueous solution containing 200 g of zinc sulfate, and the contents were heated while stirring. Boil a little. While maintaining this state, the entire sodium salt aqueous solution is dropped. Immediately after the addition, stop heating the flask and continue stirring for another 30 minutes. When the flask is allowed to stand, a light brown viscous resinous substance is released. After removing the aqueous layer, add 1,000 ml of water, stir while heating the flask, and let it stand after boiling to remove the aqueous layer. This washing operation is repeated twice. The resulting resin contains about 8 percent water. An aliquot is taken and dried at 100 ° C. for 1 hour under a vacuum of 5 torr in a vacuum dryer to obtain an analysis sample. It is a light brown transparent resin with a zinc content of 10.8% (theoretical; 11.04%) and a softening point of 97 ° C, and 3-secondary octyl-6.
-It is clear that it is zinc methyl salicylate.

Example 1-4 To 400 g of the aqueous zinc 3-secondary octyl-6-methylsalicylate obtained in Example 1-3 was added toluene 300.
Add grams and dissolve. This was put into a hard glass beaker having an internal volume of 3,000 ml, and further added with 1,200 g of water containing 3 g of sodium dodecylbenzenesulfonate and 8 g of polyvinyl alcohol having a saponification degree of 98%.
Gram and homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd .; T
(K-M type) and emulsified and dispersed at 10,000 rotations per minute for 15 minutes. Transfer the emulsion to a hard glass three-necked flask with a stirrer, thermometer, and distillation port with a capacity of 3,000 ml, and heat the bottom of the flask while stirring slowly to evaporate toluene azeotropically with water. I do. The liquid after the distillation of toluene is milky white, and the average particle size of the dispersion is
0.8 microns. A small portion is taken and dried at 100 ° C. for 1 hour under a vacuum of 20 torr and the volatile residue is 36.8 percent, which is a hydroacid solution of zinc 3-secondary octyl-6-methylsalicylate.

Example 2 In the same manner as in the above example group, a water-acid solution of 3-secondary decyl-6-methylzinc salicylate having a dry residue of 38.5% is obtained from meta-cresol and 1-decene.

Reference Example The products obtained according to Examples 1-4 and 2 were
Table 1 shows the results of measuring the degree of decomposition by microorganisms according to JIS K0102.

Example 3 100 parts of fine powdery aluminosilicate, 10 parts of zinc oxide, 9
0.5 part of polyvinyl alcohol having a saponification degree of 8%, zinc salt of a nuclear-substituted salicylic acid obtained in Examples 1-4 and 2, zinc zinc 3,5-dicyclohexylsalicylate (Comparative Example 1) and 3,5-di 10 parts of each of (α-methylbenzyl) zinc salicylate (Comparative Example 2) was added as a solid content, and water was added so that the total amount became 300 parts. Then, the mixture was added to a pot-type sand grinder of 1,000 ml / min. Disperse at 10 revolutions for 10 minutes. To the resulting dispersion, 100 parts of an aqueous polyvinyl alcohol solution having a 98% saponification degree and 10 parts (as a solid content) of a carboxy-modified styrene-butadiene latex are added, and water is further added so that the total solid content becomes 20% to prepare a paint. I do. This paint is applied to a base paper weighing 50 g per square meter with a bar coater and dried so that the remaining dry amount is 6 g per square meter to obtain a pressure-sensitive recording paper. Then, in exactly the same manner, only the zinc salt of each nucleus-substituted salicylic acid is reduced to one third to obtain a pressure-sensitive recording paper for comparison. The upper paper of a commercially available pressure-sensitive recording paper using crystal violet lactone as the paint and diisopropylnaphthalene as the solvent is superimposed on each pressure-sensitive recording paper for comparison, and printed with an electric typewriter.
Leave in a room at 20 ° C for 24 hours for comparison of recording density. Overlay the pressure-sensitive recording paper obtained above with a commercially available upper paper, print it with an electric typewriter in a room cooled to below 10 ° C, and then record the density until it becomes the same for each comparative and visual observation The time (seconds) is measured and used as a measure of instantaneous coloring. Next, this was further transferred to a room at 20 ° C., and after 24 hours, the color development density was visually evaluated and evaluated on a five-point scale. (5; most concentrated, 4; fairly concentrated, 3; slightly concentrated, 2; generally commercially available, 1; slightly inferior) The results obtained are shown in Table-2. The table also shows the average particle size (micron) of the emulsified dispersion using the zinc salt of the nuclear-substituted salicylic acid obtained in each Example.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tomoharu Shiozaki 4-3-1 Jokoji, Amagasaki City, Hyogo Prefecture Kanzaki Paper Co., Ltd. Kanzaki Mill (56) References JP-A-1-145189 (JP, A)

Claims (1)

(57) [Claims] 1. A compound of the general formula [I] (Where R ₁ represents a methyl group, an ethyl group, an isopropyl group or a secondary alkyl group, R ₂ represents a hydrogen atom, a methyl group, an ethyl group, an isopropyl group or a secondary alkyl group, R ₃ represents a methyl group, and R ₁ , developer, characterized in that a main component of zinc salt of substituted salicylic acid to the total number of carbon atoms of R ₂ and R ₃ is represented by 9 Nashii is 16).