JPH08283641A - Printing ink composition for offset rotary press - Google Patents

Abstract

PURPOSE: To obtain a printing ink for offset rotary press having high gloss and excellent drying property, press stability, resistance to misting and printability by using a solvent for a printing ink containing <=1wt.% an aromatic component. CONSTITUTION: The objective printing ink composition for offset rotary press is composed of a solvent containing >=50wt.% naphthene component and <=1wt.% an aromatic component and having a boiling point in the range of 255-280 deg.C, 260-270 deg.C boiling point of 50wt.% fraction and 75-85 deg.C an aniline point and a rosin-modified phenolic rosin not generating muddiness at 25 deg.C in producing a resin solution of <=5wt.% to the solvent. The resin-modified phenolic resin is a resin containing a rosin component, a resol-type resin component using phenols having a 10-20C alkyl group and a polyhydric alcohol component and obtained by a heating and reacting respective components in the presence of an acid catalyst, and has 3×10<4> -25×10<4> weight-average molecular weight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic printing ink composition, and more particularly to a heat set type rotary press (hereinafter referred to as "off wheel") printing ink composition.

[0002]

2. Description of the Related Art Recently, in the offset printing industry, demands for labor saving, labor saving, automation, and speeding up during printing have been increased, and stable and high quality printed matter can be obtained for a long time without trouble under various printing conditions. A lithographic printing ink that can be used is desired.
Further, the off-wheel printing is shifting from the sheet-fed printing, and the conventional leaflet-based printing has been changed to high-quality printed materials such as catalogs and posters. Generally, after printing with a printing machine, the offset printing is applied with hot air of 180 to 230 ° C. or direct flame on the printing surface to evaporate the solvent component in the ink at a paper surface temperature of 90 to 130 ° C., and then to a water-cooled type. The ink is cooled and solidified by cooling with a cooling roller and then discharged as a signature or a sheet. During printing, if poor drying occurs, the printed surface is rubbed with a guide roll, a turn bar, a triangular plate, etc., and the quality of the printed surface deteriorates, resulting in a marked loss of commercial value.

As a means for preventing poor drying, the temperature of the paper surface after printing is raised to sufficiently dry the printing surface. Reduce the amount of drying oil in the ink. It is known that the solvent used in the ink is changed to a solvent having a low boiling point. However, increasing the paper surface temperature tends to cause a blister phenomenon in which the amount of water in the printing paper decreases, causing spine cracks in the printed matter and blistering of the printed matter. Reduction of the amount of drying oil in the ink deteriorates the gloss and emulsification suitability of the printed matter. Further, lowering the boiling point of the solvent used surely improves the drying property, but the solvent evaporates even on the printing machine and the ink is apt to clog, and the stability (hereinafter referred to as on-machine stability) deteriorates.

Further, conventionally, an aromatic-containing solvent has been used as a solvent used in printing inks and paints. However, in recent years, environmental problems such as air pollution due to organic solvents and safety and health problems in the working environment have been pointed out, and in response to this, replacement with a non-aromatic ink solvent mainly containing naphthene and paraffin has been studied. There is. However, such a non-aromatic ink solvent has a drawback that it has a very poor dissolving power for a rosin-modified phenol resin. For example, Nippon Oil Co., Ltd. AF solvent (aromatic component 1% or less) has an aniline point of about 12 to 14 ° C. higher in the same boiling range than No. solvent containing aromatic component. Therefore, in the conventional rosin-modified phenolic resin, just replacing the solvent with the same boiling point as it is causes insufficient dissolving power, resulting in a decrease in gloss of the printing ink and poor printability.

Further, as the printing speed has been increased in recent years, in order to satisfy high-speed suitability such as misting resistance,
Increasing the molecular weight of ink resins is becoming indispensable. That is, it is desired to develop a resin for printing ink which has a high solubility in a non-aromatic ink solvent and a high molecular weight, as compared with a conventional rosin-modified phenol resin. Conventionally, as a means for increasing the solubility of rosin-modified phenol resin, (1) a method of using a large amount of phenol having a C9 or less alkyl group as a phenol component of rosin-modified phenol resin (2) higher fatty acid, drying oil alkyd resin, drying oil A method of using a linear modifying component such as the above has been adopted. However, in general, gloss and drying or misting are contradictory properties, and it is often difficult to balance these characteristics, and the drying property and the misting resistance are deteriorated by any of the above means.

Further, a resol type phenol resin comprising a rosin and at least one phenol component selected from octylphenol and nonylphenol,
A resin for printing ink, which is obtained by heating and reacting in the presence of an acid catalyst to lower the acid value and improving the solubility, is disclosed in JP-A-59-19.
It is disclosed in Japanese Patent No. 1776. Similarly, a reaction product (A) obtained by reacting a rosin and a phenol in the presence of an acid catalyst, and a resol type phenol resin (B) using an alkylphenol having an alkyl group having 4 to 12 carbon atoms. JP-A-1-275677 discloses a resin for a printing ink in which the acid value is lowered by reacting the above in the presence of an acid catalyst to improve the solubility.

However, the resins for printing inks obtained by these means are excellent in solubility, but they cannot obtain a sufficient molecular weight to satisfy the suitability for high speed. Therefore, it is possible to increase the molecular weight by using polyhydric alcohol or epoxy together.
The solubility of these resins is greatly reduced. However, when using a non-aromatic ink solvent, it retains sufficient solubility and simultaneously satisfies the required properties (hereinafter referred to as printability) such as high gloss and drying properties, misting resistance, and emulsion properties. The development of printing ink using resin is desired.

[0008]

DISCLOSURE OF THE INVENTION The present invention uses a solvent for a printing ink containing 1% by weight or less of an aromatic component and is excellent in high gloss and drying property, machine stability, misting resistance, and printability. It also provides printing ink for off wheels.

[0009]

That is, according to the present invention, the boiling point range is 255 to 280 ° C., and the fraction of 50% by weight is 260.
To 270 ° C., aniline point 75 to 85 ° C., naphthene content of 50% or more and aromatic component content of 1 wt% or less, and resin solvent of 5 wt% or less with respect to the solvent. The present invention relates to a printing ink composition for an offset rotary press, which comprises a rosin-modified phenolic resin having a weight average molecular weight of 30,000 to 250,000 that does not cause turbidity at 25 ° C when prepared. Further, the present invention is a resin in which a rosin-modified phenol resin comprises a rosin component, a resole-type resin component using a phenol having a C _{10 to} C ₂₀ alkyl group, and a polyhydric alcohol component, each component being an acid catalyst. The present invention relates to the above printing ink composition for an offset rotary press, which uses a rosin-modified phenolic resin which is heated and reacted in the presence of

Further, the present invention relates to the printing ink composition for offset rotary press, wherein the polyhydric alcohol component of the rosin-modified phenolic resin is used in an amount of 0.2 to 0.7 mol per mol of the rosin component. In the present invention, the solvent used has a boiling point range of 255 to 280 ° C. and a 50 wt% fraction of 260 to 270 ° C. Boiling range is lower than 255-280 ° C and 50% by weight of distillate is 260
If the temperature is lower than 0 ° C, the drying property is improved, but the on-machine stability is deteriorated. Further, those having a boiling point range of more than 255 to 280 ° C. and a fraction of 50% by weight of 270 ° C. or more have improved on-machine stability but deteriorated in drying property.

The aniline point is preferably 75 to 85 ° C. When the aniline point is 85 ° C. or higher, the solubility in the resin used in the ink composition is poor, and the fluidity, gloss and emulsification suitability of the ink deteriorate. If the temperature is lower than 75 ° C, the solvent cannot be easily removed from the ink film during drying, resulting in dry deterioration. The solvent component preferably has a naphthene content of 50% or more. If it is less than 50%, the ratio of the paraffin component, which has a poor dissolving power in the resin, increases, so that the gloss of the ink deteriorates. The content of the aromatic component in the solvent is 1% by weight or less. Aromatic components such as benzene, toluene and xylene in various solvents that have been widely used in the past generally cause skin irritation and nerve damage to the human body, as regulated by the Industrial Safety and Health Act. As a result, strict regulations are being adopted. In addition, ILO (International Labor Organization)
As has adopted a treaty to protect the safety of workers who handle chemicals, there is a growing international impetus to protect the human body from the harm of chemicals. From such a background, compared with the solvent for ink containing a large amount of aromatic components that was conventionally used, the ink using this solvent improves the working environment at the printing site and the printing ink manufacturing site, and You can protect your health.

The rosin-modified phenol resin of the present invention is a rosin (hereinafter referred to as component (A)), a resol type phenol resin (hereinafter referred to as component (B)), a polyhydric alcohol (hereinafter referred to as component (C)). ), And an acid catalyst (hereinafter referred to as component (D)). Where component (A)
Examples thereof include gum rosin, tall oil rosin, wedrodine, disproportionated rosin, polymerized rosin and modified products thereof. Examples of the component (B) phenols include 4
-Decylphenol, 4- (1-butylhexyl) phenol, 4- (1-methylnonyl) phenol, 4-
(1-Ethyloctyl) phenol, 4- (1-propylheptyl) phenol, 4- (1-ethyl-1-methylheptyl) phenol, 4- [1-methyl-1- (1
-Methylethyl) hexyl] phenol, 4- (1,1
-Dimethyloctyl) phenol, 4- [1-methyl-
1- (1-methylpropyl) pentyl] phenol, 4
-Undecylphenol, 4- (1-pentylhexyl) phenol, 4- (1-methyldecyl) phenol, 4- (1-ethylnonyl) phenol, 4- (1-
Propyloctyl) phenol, 4- (1-butylheptyl) phenol, 4-dodecylphenol, 4-
(1,1,3,3,5,5-hexamethylhexyl) phenol, 4- (1-ethyldecyl) phenol, 4-
(1-Propylnonyl) phenol, 4- (1-butyloctyl) phenol, 4- (1-pentylheptyl)
Phenol, 4- (1-methylundecyl) phenol 4- (1,1-dimethyldecyl) phenol, 4-
(1,3,5,7-tetramethyloctyl) phenol, 4-tridecylphenol, 4- (1-propyldecyl) phenol, 4- (1-butylnonyl) phenol, 4- (1-pentyloctyl) phenol, 4-
(1-hexylheptyl) phenol, 4- (1-methyldodecyl) phenol, 4-tetradecylphenol, 4-pentadecylphenol, 4-hexadecylphenol, 4- (1-methylpentadecyl) phenol, 4- ( 1-hexyldecyl) phenol, 4- (1
-Butyldodecyl) phenol, 4- (1-propyltridecyl) phenol, 4- (1-ethyltetradecyl) phenol, 4- (1-heptylnonyl) phenol, 4- (1-pentylundecyl) phenol, 4-
Heptadecylphenol, 4-octadecylphenol, 4- (1-methylheptadecyl) phenol, 4-
Nonadecylphenol, 4-eicosylphenol, 4
Examples thereof include-(1-methylnonadecyl) phenol. Further, the present invention is not necessarily limited to only C _{10 to} C ₂₀ alkylphenols, and common general-purpose phenols such as carboxylic acid, cresol, butylphenol, amylphenol, octylphenol, nonylphenol, phenylphenol, cumylphenol, etc. Can be used together. However, if the amount of carboxylic acid, cresol, butylphenol, cumylphenol, etc. used is too large, the solubility often decreases.

Examples of the aldehyde component (B) include formaldehyde and paraformaldehyde. The amount of aldehyde used with respect to the phenol component is 1 to 4 mol, preferably 1.5 to 3 mol, per 1 mol of the phenol component. Resol-type phenolic resin is known, and is obtained by reacting in the presence of an alkali catalyst. Examples of alkali catalysts include oxides of sodium, calcium, zinc, potassium, magnesium, etc., hydroxides or acetates, or ammonia, lower organic amines, etc. Used in percentage by weight.

The amount of the component (B) used is appropriately determined in consideration of the solubility and softening point of the rosin-modified phenol resin obtained together. The amount of component (B) used is 100 for component (A).
It is usually about 30 to 120 parts by weight, preferably 40 to 100 parts by weight, based on parts by weight. If the amount used is less than 30 parts by weight, a rosin-modified phenolic resin having the desired solubility cannot be obtained, and if it exceeds 120 parts by weight, the solubility will be too good, resulting in dryness, Misting deteriorates and neither is preferable. The component (C) is not particularly limited and various known ones can be used, and specific examples thereof include glycerin, trimethylolethane, trimethylolpropane, diethylene glycol, pentaerythritol and the like.

The amount of component (C) used is 0.2 mol to 0.7 mol, preferably 0.3 to 0.6 mol, per 1 mol of component (A). If the amount used is less than 0.2 mol, a rosin-modified phenol resin having a desired molecular weight cannot be obtained, and if it exceeds 0.7 mol, a rosin-modified phenol resin having a desired solubility is not obtained. I can't get it. Examples of the component (D) include sulfonic acid salts such as paratoluene sulfonic acid, dodecylbenzene sulfonic acid, methane sulfonic acid and ethane sulfonic acid, or mineral acids such as sulfuric acid and hydrochloric acid.
It is about 0.01 to 2 parts by weight based on 100 parts by weight of (B) in total. In the present invention, the reaction method is not particularly limited, as long as the above components are used in predetermined amounts.
The ink resin of the present invention can be easily obtained by directly adopting the conventionally known method for producing a rosin-modified phenolic resin.

Further, the solubility of the rosin-modified phenol resin of the present invention is 2 when the solubility using the ink solvent of the present invention is 2
It is preferably 5% by weight or less at 5 ° C. The method of expressing the solubility is indicated by the weight% of the resin in the solution at the point where the system is white and becomes turbid after the resin is heated and dissolved in the solvent used, and the solvent is added dropwise at 25 ° C. with stirring. Therefore, the more compatible the resin, the lower the resin weight% at the point of clouding. If it is 5% by weight or more, the solubility of the resin deteriorates and the gloss decreases. The rosin-modified phenol resin of the present invention has a molecular weight of 30,000 to 250,000, preferably 40,000 to 200,000. This is because if it is less than 30,000, the misting resistance is significantly reduced. The softening point of the resin is not particularly limited, but is usually about 120 to 200 ° C. This is because if the temperature is lower than 120 ° C, the drying property is lowered.

The thus-obtained ink solvent and rosin-modified phenol resin of the present invention are made into printing ink by appropriately blending various known pigments, drying oils, various additives and the like by a conventional method and kneading. I can do something. When adjusting the above-mentioned ink, a known rosin-modified phenolic resin may be used together within a range that does not reduce the effects of the present invention.

[0018]

The present invention will be described below with reference to examples. In the examples, parts and% are parts by weight and% by weight, respectively. Production Example 1 (Production Method of Resol-Type Phenolic Resin Initial Condensate) After stirring, 4- (1,1 dimethyloctyl) phenol 1 was placed in a four-necked flask equipped with a reflux condenser with a water separator and a thermometer.
A mixture of 000 parts, 875 parts of 35% formalin and 60 parts of 93% sodium hydroxide was heated to 95 ° C. and reacted for 3 hours, then 1000 parts of toluene was added, the resin was dissolved in toluene, and 6N hydrochloric acid 125 Part, 1000 parts of water in a hydrochloric acid solution, stirred and allowed to stand, and the supernatant layer of PH5-6 was taken out and washed with water, and a toluene solution of a resol type phenol resin (initial condensate) A having a nonvolatile content of 50% About 200
I got 0 copies. Production Example 2 The same as in Production Example 1 except that 4- (1,1 dimethyloctyl) phenol was changed to 4- (1,1,3,3,5,5-hexamethylhexyl) phenol in the process shown in Production Example 1. The operation was performed to obtain about 2000 parts of a toluene solution of a resol-type phenol resin (initial condensation product) B having a nonvolatile content of 50%. Production Example 3 In the process shown in Production Example 1, the same operation was performed except that 4- (1,1 dimethyloctyl) phenol was changed to 4-pentadecylphenol, and a resol type phenol resin having a nonvolatile content of 50% (initial Condensate) C toluene solution about 2
I got 000 copies. Production Example 4 In the process shown in Production Example 1, the same operation was performed except that 4- (1,1-dimethyloctyl) phenol was changed to 4- (1-methylpentadecyl) phenol, and a nonvolatile content of 50% was obtained. About 2000 parts of a toluene solution of a resol type phenol resin (initial condensation product) D was obtained. Production Example 5 In the process shown in Production Example 1, the same operation was performed except that 4- (1,1 dimethyloctyl) phenol was changed to 4- (1-methylnonadecyl) phenol.
%, About 2000 parts of a toluene solution of a resol type phenol resin (initial condensation product) D was obtained. Production Example 6 In the process shown in Production Example 1, the same operation was performed except that 4- (1,1 dimethyloctyl) phenol was changed to 4-octylphenol, and a resol type phenol resin having a nonvolatile content of 50% (initial condensate). ) D toluene solution about 200
I got 0 copies. Example 1 A 4-necked flask equipped with a stirrer and a Liebig condenser thermometer was charged with 1000 parts of gum rosin, 1200 parts of resol-type phenol resin A (corresponding to 600 parts of phenol resin), 40 parts of glycerin, and 3 parts of paratoluenesulfonic acid as a catalyst. , Heating while distilling off toluene, 240-
Reaction at 250 ° C for 3 hours, acid value 20, softening point 169
About 2000 parts of a rosin-modified phenolic resin having a solubility in the ink solvent of the present invention of 5% by weight or less was obtained. Examples 2 to 5 The reaction was performed in the same manner as in Example 1 except that the resol-type phenol resin A used was changed to the composition shown in Table 1 to obtain a rosin-modified phenol resin of the present invention.
The resin constants are shown in Table 1. Examples 6 to 8 Reactions were performed in the same manner as in Example 1 except that the resole-type phenol resin A used had the composition shown in Table 1 and the amount of the phenol resin used was changed as shown in Table 1. Then, the rosin-modified phenol resin of the present invention was obtained. The resin constants are shown in Table 1. Examples 9 to 10 Reactions were performed in the same manner as in Example 1 except that the resole-type phenol resin A used had the composition shown in Table 1 and the amount of glycerin used was changed as shown in Table 1. A rosin-modified phenol resin of the present invention was obtained. The resin constants are shown in Table 1. Examples 11 to 12 The reaction was performed in the same manner as in Example 1 except that the resol type phenol resin A used was changed to the composition shown in Table 1 to obtain a rosin-modified phenol resin of the present invention.
The resin constants are shown in Table 1. Comparative Examples 1 to 3 Reactions were performed in the same manner as in Example 1 except that the resol-type phenol resin A used had the composition shown in Table 1 and the amount of glycerin used was changed as shown in Table 1. , A comparative resin was obtained. The resin constants are shown in Table 1.

[0019]

[Table 1]

The rosin-modified phenolic resins obtained in the respective Examples and Comparative Examples were used to prepare inks for Examples and Comparative Examples based on the vehicle ink formulations shown in Table 2. The specifications of the ink solvent used are shown in Table 3.

[0021]

[Table 2]

[0022]

[0023]

[Table 3]

Regarding the inks obtained in each example, L-400 manufactured by Mitsubishi Heavy Industries, Ltd., 4-color off-wheel printer, T manufactured by Inoue Metal Co., Ltd.
The test was carried out using an EC dryer device. As the dampening water, a 1.5% solution of Acwa Magic NS (etching solution manufactured by Toyo Ink Mfg. Co., Ltd.) was used. The print evaluation items and conditions are as follows, and the evaluation results are shown in Table 4.

[0025]

[Table 4]

Gloss: A printed matter having a paper surface drying temperature of 100 ° C. was measured using a gloss meter GM26D (60 ° -60 °) manufactured by Murakami Color Research Laboratory. Dryability: Printing was carried out under the above conditions, and comparison was made by the sticky feel of the solid portion, and comparison was made by the paper surface temperature when the sticky feeling disappeared. Misting: Each ink was printed under the above conditions, a blank sheet was put on the printing unit, and the misting state after continuous 10,000 sheets were printed was evaluated by 5 grades. On-machine stability: 10,000 sheets of each ink were continuously printed under the above conditions, and compared with the feel of stickiness on both ends of the kneading roller (outside the paper width). It was set as Δ.

Emulsification suitability: A water dial value is set higher than usual, a kneading roller is peeled off, and ink accumulation on the roller is compared. The product in which neither was generated was evaluated as ◯, the product in which both were generated was evaluated as x, and the product in which one was generated was evaluated as Δ. From this result, it is clear that the offset rotary printing ink composition of the present invention is an ink having high gloss and excellent drying property, machine stability, misting resistance, and printability.

[0028]

The printing ink composition for offset rotary printing according to the present invention can greatly improve the drying property, the on-machine stability, the misting resistance and the printability without lowering the gloss of the printing surface. We were able to meet the demands for labor saving, labor saving, and speeding up at the time of printing, and under the various printing conditions, we were able to provide trouble-free, stable, high-quality printed matter for a long time. In addition, by using a non-aromatic ink solvent, it was possible to improve the working environment at the printing site and printing ink manufacturing site and protect the health of the site workers.

[Procedure amendment]

[Submission date] May 12, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction content]

[0019]

[Table 1]

Claims (3)

[Claims] 1. A boiling point range of 255 to 280 ° C., a 50 wt% fraction of 260 to 270 ° C., and an aniline point of 75 to 85.
A solvent having a naphthene content of 50% or more and an aromatic content of 1% by weight or less as a component, and 5% with respect to the solvent.
A printing ink composition for an offset rotary press, comprising a rosin-modified phenolic resin having a weight average molecular weight of 30,000 to 250,000, which does not cause turbidity at 25 ° C. when a resin solvent is prepared in an amount of not more than 5% by weight. 2. A rosin-modified phenolic resin is a resin containing a rosin component, a resole-type resin component using a phenol having a C ₁₀ -C ₂₀ alkyl group, and a polyhydric alcohol component, each component being an acid catalyst. A rosin-modified phenolic resin obtained by heat-reacting in the presence of
A printing ink composition for an offset rotary press as described. 3. The amount of the polyhydric alcohol component of the rosin-modified phenol resin used is 0.2 with respect to 1 mol of the rosin component.
The printing ink composition for an offset rotary press according to claim 1 or 2, wherein the printing ink composition has an amount of about 0.7 mol.