JPS59191776A - Printing ink resin - Google Patents

Abstract

PURPOSE:To provide a printing ink resin excellent in solubility, by incorporating a rosin-modified phenolic resin having a particular solubility, prepd. by the reaction of a resol-type phenolic resin with rosin in the presence of an acid catalyst. CONSTITUTION:A printing ink resin which comprises a rosin-modified phenolic resin having such a solubility that no turbidity appears at 25 deg.C in a soln. of 25wt% or lower said rosin-modified phenolic resin in a 16C aliph. hydrocarbon solvent, said rosin-modified phenolic resin being prepd. by the reaction of a resol-type phenolic resin with rosin in the presence of an acid catalyst at a temp. of 150 deg.C or above to lower the acid value to 30 or below. Long-chain alkyl phenols such as octylphenol or nonylphenol pref. as the principal phenolic component of phenolic resins with respect to solubility. The softening point of rosin may be further increased by replacing the whole or part of the rosin by a polymerized rosin a part of which is subjected to dimerization.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resin for printing ink with excellent solubility, which is mainly made by reacting a rosin and a resol type phenolic resin under an acid catalyst to lower the acid value.

In recent years, aliphatic hydrocarbon solvents, that is, paraffinic solvents, have been increasingly used as solvents for printing inks and paints for various reasons. The main reasons include quick drying, low odor, and low risk of air pollution. For example, in the case of offset rotary ink, as the printing speed increases, it is necessary to increase the amount of heat in the hot air dryer.
Paraffin-based solvents do not swell the rubber of the rollers, and can be used to replace quick-drying inks that evaporate quickly.

It becomes possible to lower the hot air temperature. Also, due to the evaporation of solvents in paints and gravure inks.

In many countries, including the United States, regulations are being put in place to limit its usage. In particular, oxygen-containing solvents such as ketones and alcohols seem to be closely related to oxidant formation, and the use of paraffinic solvents is attracting attention. However, a characteristic of such paraffinic solvents is that they have extremely poor dissolving power. Therefore, the resins that can be used in combination with paraffinic solvents are severely limited.

Not fully utilized. It is especially widely used in printing inks. Most rosin-modified phenolic resins are either not compatible with paraffinic solvents at all, or even if they are compatible, they have low tolerance and cannot be used at high solvent ratios. Although it is possible to partially denature, or esterify, with alcohol to make it compatible with paraffinic solvents, this lowers the softening point, and the film after the ink and other solvents are removed is soft and sometimes tacky (viscous). In high-speed off-wheel printing, this can cause the film to rub off on the folding machine, etc., and blocking while stacking printed materials.
This is undesirable as it may cause an accident in which the printed surfaces stick together. In other words, it is desired that the softening point of the rosin-modified phenolic resin be kept as high as possible, and that the resin can be mixed with paraffinic solvents in a wide range of ratios.

Here, an example of a conventional rosin-modified phenol resin will be explained. First, a resol type phenolic resin and rosin are reacted at a temperature of 200°C or higher.

Subsequently, add polyol such as glycerin to 230 to 260
Esterification is carried out at ℃ until the acid value becomes 30 or less. In this case, paratertiary butylphenol and paraoctylphenol are commonly used as resol type phenolic resins.

Phenols such as paranonylphenol are used alone or in combination. The resol type phenolic resin is synthesized by using an alkali such as caustic soda, caustic potash, ammonia, calcium hydroxide, etc. and reacting it with formaldehyde, paraformaldehyde, etc. according to a conventional method. The reaction ratio between rosin and resol type phenolic resin is determined based on the performance required for each application, price, etc.
In many cases, the rosin to phenolic resin ratio is 1 to 0.2.
The reaction is usually carried out at a ratio of 1 to 1.3 (weight ratio). Regarding the reaction type between rosin and phenolic resin,
There are various proposals, but since the acid value of the carboxyl group of lysine hardly changes, esterification between the methylol group in the phenol resin and the carboxyl group of rosin does not actually occur, or even if it does occur, it is minimal. It is believed that there is. On the other hand, when the resin contains a large amount of carboxyl groups.

In offset printing, which uses water, a reaction with basic pigments may occur, causing the ink to deteriorate over time.

It has a high affinity for the plate material and causes problems such as stains. Therefore, the carboxyl group of rosin after reacting with phenolic resin is converted into neopentyl glycol, chrycerin, and trimethylolpropane.

It is esterified with a polyhydric alcohol such as pentaerythritol to lower the acid value to 30 or less. Alternatively, a method in which rosin, phenolic resin, and polyhydric alcohol are reacted all at once is also being considered. Even in this method, esterification of rosin and polyhydric alcohol mainly occurs compared to esterification of rosin and phenol resin. In addition, it has been considered to react rosin and phenolic resin using a catalyst, but this is not intended to be an esterification reaction between rosin and phenolic resin, and it is not intended to be an esterification reaction between rosin and phenolic resin. Measures have been taken to use alcohol in combination.

However, resins esterified with polyhydric alcohols appear to be difficult to dissolve in paraffinic solvents, and their 1W
To solve this problem, measures have been taken to use large amounts of phenols with large alkyl substituents. For example, resol type phenolic resins made of paraoctylphenol and paranonylphenol are reacted with rosin. The composition of a typical face for offset ink is approximately a weight ratio of resin/drying oil (or polymerized drying oil)/solvent (25 to 50)/(0 to
30)/(20 to 50), and in some cases, the resin may be dissolved and used only with a solvent. In this way, the tolerance of solvents to resins is an extremely important property.

If this tolerance is low, the surface will become cloudy and the fluidity of the obtained ink will be very poor. As mentioned above, methods to obtain resins with good compatibility with solvents have been to use long-chain alkylphenols or to partially use higher fatty acids, but according to this method, the softening point of the resin The setting speed of the ink becomes slower. Setting refers to the phenomenon in which the low viscosity components of the ink, especially the solvent, are absorbed into the paper fibers and coating layer immediately after printing, causing a rapid thickening of the ink, causing the color to appear on the back side of the printed matter that accumulates one after another. It is possible that the disease will become permanent. In high-speed printing, an important property of -C is required to be quick setting before reaching a dry state, and for this purpose it is extremely advantageous that the softening point of the resin is =6- higher. From this point of view, it is not desirable to simply use too many long-chain alkylphenols or modify the resin with fatty acids as a means of increasing the solubility of the resin. The softening point of general offset/7 ink resin is 120℃~
160°C (hand-in-pillar method) is widely used.

On the other hand, there are various methods to express the compatibility between a resin and a solvent, but those skilled in the art can measure the compatibility by heating and dissolving the resin in the solvent to be used or a similar solvent, then adding the solvent dropwise at 25°C and stirring. It is expressed as the weight percent of the resin in the solution at which the system becomes white and becomes cloudy. Therefore, resins with good compatibility have a low resin weight percentage at the point where the resin becomes cloudy. Hereinafter, this display will be referred to as a cloudy point.

The clouding point of the printing ink resin is preferably 40% by weight or less, preferably 25% by weight or less, as measured by the solvent used. 5 In the examples of this specification,
It is indicated by the cloudy point measured using normal hexadecane having 16 carbon atoms.

When using a resin with a high cloudiness point, it can be supplemented by using an aromatic solvent with good solubility, such as a solvent containing a large amount of dodecylbenzene, or by using a combination of tung oil, linseed oil, etc., but setting and drying It has the disadvantage of being delayed.

Among offset inks, the present inventors have developed a method for using a resin specifically applied to H-1, C-2, and 2-type offset rotary inks (hereinafter abbreviated as off-wheel inks), which often uses aliphatic hydrocarbon solvents. It shows a low value of 20% or less, and a softening point of 130°C or more. The present invention was completed by discovering a so-called high softening point, high solubility resin.

That is, a rosin-modified phenolic resin is produced by reacting a resol type phenolic resin and rosin at a temperature of at least 150°C in the presence of an acid catalyst to give an acid value of 30 or less, and using an aliphatic hydrocarbon solvent having 16 carbon atoms. This resin for printing ink is a rosin-modified phenolic resin that exhibits solubility that does not cause turbidity at a temperature of 25° C. when the solution is 25% by weight or less. This printing ink resin is useful for offset printing ink with strict physical properties requirements, but it is not suitable for single-sheet printing ink.

Of course, it can also be used for letterpress ink, gravure ink, etc.

As mentioned above, it is not preferable for the offset resin to have an excessive amount of free carboxyl groups in view of printability. Therefore, measures are taken to block the carboxyl groups with some kind of functional group so that the acid value is 30 or less, preferably 20 or less.

Esterification is often carried out with alcohols, especially polyhydric alcohols, but also with isocyanates.

It is also possible that this is due to reaction with amines, epoxies, etc.

However, no matter which reaction is selected, these have in common that they deteriorate the solubility in aliphatic solvents. Therefore, the present inventor investigated whether it was possible to obtain a resin with a low acid value using only rosin and resol-type phenolic resin without using polyols, etc., and found that by reacting rosin and phenolic resin in the presence of an acid catalyst. 2. It was discovered that in addition to the usual reaction between rosin and resol type phenolic resin, an esterification reaction occurs in which carboxyl groups are reduced as indicated by a reduction in acid value. It is true that resol-type phenolic resin has a highly reactive methylol group at the end, and it seems that esterification with the carboxyl group of rosin can be expected, but in the absence of an acid catalyst, alcohol and rosin easily separate. Even when heated above the esterification temperature (260°C), the acid value hardly decreases, and the methylol group undergoes other reactions such as addition to the phenol nucleus, esterification between methylols, and subsequent elimination. It is thought that it has disappeared due to formalization or the like, or remains in an unreacted state, so that the normally expected esterification is unlikely to occur.

However, when heated above 150°C in the presence of an acid catalyst, the acid value easily decreases. In addition to temperature, the rate at which the acid value decreases depends on the amount of resol type phenolic resin added to rosin and the molecular weight (degree of polymerization) of resol type phenolic resin.
It also changes depending on.

Acids are most effective as esterification catalysts, such as para-toluenesulfonic acid and dodecylbenzenesulfonic acid.

Sulfonic acids such as methanesulfonic acid and ethanesulfonic acid or mineral acids such as sulfuric acid and hydrochloric acid are suitable for this purpose. However, in the presence of sulfonic acid, sulfuric acid, etc., rosin is easily colored by heating, and there is a risk of affecting the hue of the ink, so it is preferable to use hypophosphorous acid, triphenyl phosphite, etc. in combination. In addition, coloring can be suppressed by mixing these catalysts with a toluene solution of phenolic resin or adding them to a rosin and phenolic resin mixture instead of mixing them into the rosin melt. It should be noted that with the base catalyst generally used for the esterification reaction, esterification of the resol type phenol resin and the rosin or its derivative -10~ conductor does not occur, so it is advantageous to use an acid catalyst because it shortens the time. .

The esterification reaction between rosin and resol-type phenolic resin is carried out using the above acid catalyst at a weight ratio of rosin to phenolic resin of 1:0.1 to 1:1.5, preferably 1:0.5 to 1:1.3. This is carried out using 0.01 to 2 parts by weight based on a total of 100 parts by weight of the phenolic resin and rosin at two temperatures of 150°C or higher, preferably 200 to 260°C. In addition, at a temperature below 150°C, the esterification reaction hardly progresses and cannot be said to be a practical condition.

The phenolic components of phenolic resins include, for example, phenol, cresol, tertiary or secondary butylphenol, amylphenol, cyclohexylphenol, octylphenol, nonylphenol, phenylphenol, cumylphenol, bisphenol, among others long-chain alkylphenols, such as octylphenol. , nonylphenol is preferred from the viewpoint of solubility. Furthermore, the present invention is not necessarily limited to long-chain alkylphenols, and other phenols can also be used in combination with long-chain alkylphenols. However, 2 For example, tertiary
If the amount of butylphenol, paracumylphenol, carbolic acid, cresol, bisphenol A, bisphenol F, etc. used is too large, solubility often decreases.

In particular, since bisphenol A is polyfunctional, it can increase the molecular weight and softening point of the resin, but care must be taken when using it because the solubility decreases.

Examples of aldehyde components include pormaldehyde,
Examples include rose formaldehyde.

The usage ratio of aldehyde to phenol component is 1 to 4 mol per 1 mol of phenol component, and <1.5
It is preferable to set it in the range of ~3 mol.

Resol type phenolic resins are known and can be obtained by reaction in the presence of an alkali catalyst.

It is preferable to use a so-called initial condensate that is in a liquid, semi-solid or crystalline state at room temperature, but it is also possible to use a product that has undergone further condensation. The resol type initial condensate is prepared by using the above-mentioned phenol component and aldehyde component in the above-mentioned ratio and in the presence of an alkali catalyst.
It can be obtained by reacting at a temperature of 0°C for about 2 to 5 hours.

Examples of the alkali catalyst include oxides, hydroxides or acetates of sodium, potassium, magnesium, calcium, zinc, etc., ammonia, lower organic amines, etc., and these are 0.1 to 5% by weight based on the phenol component. used at a rate of

Rosin components include gum rosin, wood rosin, 1.
- oil rosins, their modifications and mixtures thereof can be used. What is the denaturation reaction?

Examples include partial hydrogenation, disproportionate monopolymerization, aldehyde modification, and carboxylic acid modification. In addition, since industrial rosin has a softening point of around 62°C, it is not advantageous for increasing the softening point of the reaction product with resol-type phenolic resin. By replacing part or all of the rosin, the softening point can be further raised. Furthermore, by replacing part or all of the rosin with a rosin derivative obtained by adding an unsaturated carboxylic acid such as maleic acid, fumaric acid, or itaconic acid to rosin, a resin with a higher softening point can be obtained. When using these rosin derivatives, it should be noted that increasing the amount of resol type phenolic resin 13- may cause gelation. Since the rosin-modified phenolic resin according to the present invention has a low acid value, it is not necessarily necessary to further esterify it with a polyhydric alcohol.
In addition to polyhydric alcohols commonly used in the synthetic resin field such as diethylene glycol, propylene glycol, neopentyl glycol, pentaerythritol, dipentaerythritol, THEIC (2-hydroxyethyl isocyanurate), etc. You can also use epoxy. The solubility of materials such as these polyhydric alcohols in aliphatic solvents deteriorates as esterification with rosin progresses, so the amount that can be used is limited to a small amount. In most cases, less than about 5% by weight in the resulting resin is preferred.

2. In the present invention, the polyhydric alcohol and rosin are partially esterified in advance, and then reacted with a resol type phenol resin in the presence of an acid catalyst, and the resol type phenol resin, rosin, and polyhydric alcohol are It is also possible to esterify the phenol resin, rosin, and 14- by reacting them without a catalyst and then adding an acid catalyst.

In order to prepare a varnish for offset printing using the printing ink resin of the present invention, it is dissolved in 80 to 200 parts by weight of a solvent and/or a drying oil (or polymerized drying oil) per 100 parts by weight of the resin.

For actual use, apply yellow to the varnish mentioned above.

Ink is made by blending pigments such as indigo, red, or black, an anti-friction improver (wax-based compound), a gelling agent, and an ink dryer.

It is used as lithographic ink such as offset ink and rotary ink, newspaper printing ink, letterpress ink, etc. In addition, in order to make a varnish for gravure or flexographic ink using the resin of the present invention, an aliphatic hydrocarbon and/or alicyclic solvent having a boiling point of 140°C or less at normal pressure is added to
00 parts by weight, 100 parts by weight of the resin is dissolved.

Next, the present invention will be explained using specific examples. In the example, "part", 1
%" means 2 parts by weight and 1% by weight.

Production Example 1 (Production of resol-type phenolic resin initial condensate) In a four-sol flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, 200 parts of baraoctylphenol, 170 parts of 35% formalin, and 93% sodium hydroxide were added. A mixture of 12 parts was heated to 90°C and after 3 hours of reaction, 200
of toluene was added, the resin was dissolved in toluene, a hydrochloric acid solution of 25 parts of 6N hydrochloric acid and 200 parts of water was added, stirred and allowed to stand, and the supernatant layer with a pH of 5 to 6 was taken out and washed with water.

Approximately 400 parts of a toluene solution of resol type phenol resin (initial condensate) A having a nonvolatile content of 50% was obtained.

Production Example 2 Rose octylphenol 200 was produced by the process shown in Production Example 1.
The same procedure was carried out except that instead of 170 parts of paraoctylphenol and 22 parts of paratertiary butylphenol, a mixture of 170 parts of paraoctylphenol and 22 parts of paratertiary butylphenol was used.

About 400 parts of a toluene solution of resol type phenol resin (initial condensate) B with a nonvolatile content of 50% was obtained.

Production Example 3 In the process shown in Production Example 1, rose octylphenol 20
Exactly the same operation was performed except that a mixture of 170 parts of para-octylphenol and 33 parts of bisphenol A was used instead of 0 parts, to obtain about 400 parts of a toluene solution of resol type phenol resin (initial condensate) C with a non-volatile content of 50%. Ta.

Production Example 4 In the process shown in Production Example 1, rose octylphenol 20
Exactly the same operation was carried out except that a mixture of 140 parts of paraoctylphenol, 30 parts of paranonylphenol, and 30 parts of paratertiary-butylphenol was used instead of 0 parts of resol type phenolic resin (initial condensate) D with a nonvolatile content of 50%. Approximately 400 parts of toluene solution was obtained.

Example 1 (Production of highly soluble rosin-modified phenolic resin) Stirrer,
In a four-normo flask equipped with a Liebig condenser thermometer,
100 parts of gum rosin, 200 parts of toluene solution of resol type phenolic resin A (equivalent to 100 parts of phenolic resin),
0.3 parts of para-toluenesulfonic acid and 0.3 parts of hypophosphorous acid were added as a catalyst, heated while distilling toluene off, and reacted at 250 to 260°C for 2 hours, resulting in an acid value of 20.
．． Approximately 200 parts of a rosin-modified phenolic resin having a softening point of 135° C. (capillary method) was obtained.

The obtained normal hexadecane solution of the rosin-modified phenol resin with a resin concentration of 10% exhibited transparency at 25°C.

17- The infrared absorption spectrum of the obtained rosin-modified phenolic resin of the present invention is not shown in FIG. In the spectrum shown in Figure 1, a carbonyl peak representing an ester bond is clearly seen at 1720 cm'' (Kaiser).
The heat resistance at 00 cm has clearly decreased.

Example 2 In the process of Example 1, toluene solution 2 of phenolic resin B
00 parts (equivalent to 100 parts of phenolic resin).

Example 1 except that 0.3 parts of para-toluenesulfonic acid and 0.3 parts of triphenylphosphite were used as catalysts.
Perform exactly the same operation as above to obtain an acid value of 20. Softening point 145℃ (
Capillary method) rosin modified phenolic resin approx. 200
I got the department.

The obtained normal hexadecane solution of the rosin-modified phenol resin with a resin concentration of 15% exhibited transparency at 25°C.

Example 3 In a reactor similar to that shown in Example 1, 200 parts of a toluene solution of phenolic resin 1]IC (equivalent to 100 parts of phenolic resin) and 100 parts of gum rosin were added.

=18= 0.1 part of hydrochloric acid was added as a catalyst, heated while distilling off toluene, and the reaction was carried out at 210 to 220°C for 4 hours, resulting in an acid value of 20. Approximately 200 parts of a rosin-modified phenolic resin having a softening point of 145°C (capillary method) was obtained.

The obtained normal hexadecane solution of the rosin-modified phenol resin with a resin concentration of 20% exhibited transparency at 25°C.

Example 4 Into a reactor similar to that shown in Example 1, 200 parts of a toluene solution of phenolic resin A (100 parts of phenolic resin
equivalent) 100 parts of 1 polymerization mouth gin.

Add 0.3 parts of para-toluenesulfonic acid and 0.3 parts of hypophosphorous acid, distill off toluene and heat to 250 to 260
℃ for 1 hour to give an acid value of 40. After adding 2 parts of glycerin, the reaction was further carried out at 250 to 260℃ for 3 hours to give an acid value of 20. Approximately 200 parts of a rosin-modified phenolic resin having a softening point of 140° C. (capillary method) was obtained.

The obtained normal hexadecane solution of the rosin-modified phenol resin with a resin concentration of 15% exhibited transparency at 25°C.

Example 5 In the process of Example 1, toluene solution of phenolic resin 2
00 parts (equivalent to 100 parts of phenol resin) was used, but the same operation as in Example 1 was performed, and the acid value was 20. Approximately 200 parts of a rosin-modified phenolic resin having a softening point of 135'C (capillary method) was obtained.

The obtained normal hexadecane solution of the rosin-modified phenol resin with a resin concentration of 10% exhibited transparency at 25°C.

Example 6 100 parts by weight of gin was placed in a solo flask equipped with a stirrer,
While blowing inert gas, the temperature is raised to 230°C, and the mixture is melted and stirred. 10 parts by weight of fumaric acid is added into the molten rosin while being careful to prevent foaming.

Next, after continuing stirring at 230°C for 40 minutes, 140 parts by weight of phenolic resin A (equivalent to 70 parts by weight of phenolic resin) added in advance to 0.7 parts by weight of dodecylbenzenesulfonic acid and 0.7 parts by weight of hypophosphorous acid was added dropwise. do. After dropping, the resin obtained by reacting at the same temperature for 3 hours has a softening point of 143°C (capillary method) and a cloudiness point of 22 with n-hexadecane.
%Met.

Comparative Example 1 A reaction apparatus similar to that shown in Example 1 was charged with 200 parts of a toluene solution of phenolic resin (100 parts of phenolic resin).
100 parts of gum rosin was added, heated while distilling off toluene, and reacted at 250 to 260°C for 2 hours, and the acid value was 80. Furthermore, the acid value of the rosin-modified phenol resin obtained by adding 10 parts of glycerin and reacting at 250 to 260°C for 8 hours was 20, but the normal hexadecane solution with a resin concentration of 35% became cloudy and opaque at 25°C. there were.

Comparative Example 2 The acid value of a rosin-modified phenolic resin obtained by performing the same procedure as in Comparative Example 1 except that phenolic resin B was used instead of phenolic resin A was 20. A normal hexadecane solution with a concentration of 50% is 25
It became cloudy and opaque at ℃.

Comparative Example 3 The same procedure as in Example 1 was performed except that 0.5 part of sodium hydroxide was used instead of para-toluenesulfonic acid and primary hypophosphorous acid, but the acid value did not change at all. figure,
It is thought that 21- has not undergone an esterification reaction.

Comparative Example 4 The same operation as in Example 1 was performed except that the reaction temperature was changed to 125°C, but the acid value did not change at all.
No esterification reaction occurred.

An ink varnish was prepared using the rosin-modified phenolic resin obtained in each of the Examples and Comparative Examples.

After forming into an ink, the developed color gloss and cent of each printing ink were measured, and the results are shown in Table 1. In addition.

The printing ink of Comparative Example 3.4 had poor emulsion resistance.

(Preparation of printing ink) 50 parts of the obtained rosin-modified phenolic resin, 36.5 parts of phenolic resin 5 (manufactured by Kogaku side), 12 parts of No. 00 linseed oil, AL-C
65 parts of gel varnish consisting of 1.5 parts of H (Yoken Fine Chemical i gelling agent), 19 parts of pigment (Carmine 6B manufactured by Toyo Ink Mfg. @) and 6 parts of No. 0 solvent H1 were mixed and kneaded with three rolls. and tank 5.5~6.0,
The printing ink was adjusted to have a flow of 19.0 to 21.0.

22- Table 1 - [Cent Test] After spreading 3 cc of Ink Q on coated paper (Mitsubishi Pearl Co. 66.5K) with R1 raster, 160
°C Place it in the oven and the time it takes until it feels no longer sticky to the touch (
seconds) was measured.

[Gloss test]

After spreading 0.3 cc of ink on coated paper using an R■ tester, it was dried in an oven at 160°C for 3 seconds.

- It was left standing day and night and measured using a 60°-60° gloss meter.

The results are shown in Table 1. The gloss and set of the printing ink using the resin according to the invention are both good.

This could be effective as a resin for offset inks.

[Brief explanation of the drawing]

¥1 The drawing shows the infrared absorption spectrum of the rosin-modified phenolic resin according to the present invention. Patent applicant: Toyo Ink Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. Resol type phenolic resin and rosin are reacted at a temperature of at least 150°C in the presence of an acid catalyst to give an acid value of 30 or less, and an aliphatic hydrocarbon solvent having 16 carbon atoms is used. A resin for printing ink, characterized in that the resin is a rosin-modified phenolic resin that exhibits solubility that does not cause turbidity at a temperature of 25° C. in a solution containing 25% by weight or less of the rosin-modified phenolic resin. 2. The resin for printing ink according to claim 1, which is a resol type phenolic resin mainly containing at least one selected from octylphenol and nonylphenol. 3. The resin for printing ink according to claim 1 or 2, wherein the rosin is a polymerized rosin. 4. The resin for printing ink according to claim 1 or 2, wherein the rosin is an adduct of at least one selected from maleic acid and fumaric acid.