JP5098342B2 - Resin varnish for printing ink and printing ink - Google Patents

Description

  The present invention relates to a resin varnish for printing ink that can provide a printing ink excellent in emulsification ability and gloss of printed matter, and the printing ink.

Alkyd resins used for lithographic offset printing inks have the effect of increasing the gloss of printed matter and are generally used as raw materials for printing ink varnishes.
However, since the alkyd resin generally has a high acid value and a high hydroxyl value, it reduces the water resistance and emulsification ability of the ink and causes stains on the printed matter. Therefore, the amount of alkyd resin used in the resin varnish for printing ink Was limited.

  In lithographic offset printing using fountain solution, the emulsification ability of the ink is an important quality characteristic for obtaining stable printing and excellent printed matter. In lithographic offset printing, the ink is constantly emulsified by contact with dampening water on the printing press. However, if the emulsification is too small, it may cause ink transfer failure, etc. Become. Accordingly, there is a need for a printing ink that can maintain a stable emulsified state even under various printing conditions.

As a method for improving the water resistance of the alkyd resin, there is a method in which a hydroxyl group contained in the alkyd resin is reacted with a monovalent carboxylic acid anhydride to remove the by-produced monovalent carboxylic acid (for example, Patent Document 1). reference).
However, when the acid value of the alkyd resin “Arachid 5001” (manufactured by Arakawa Chemical) described in Examples 1 to 3 of Patent Document 1 was measured, it was 13.8 mgKOH / g. As described in Examples 1 to 3 of Patent Document 1, this “Arachid 5001” was reacted with a monovalent carboxylic acid anhydride to remove the by-produced monovalent carboxylic acid, and the hydroxyl value of the modified alkyd resin. Is 2 or less, but the acid value is 9 to 13 mg KOH / g, and the acid value is high, so the emulsification suitability of the ink is not sufficient. Further, in this method, since it is necessary to add a step for removing the by-product monovalent carboxylic acid, the productivity may be lowered.
In Example 4 of Patent Document 1, an example using a low acid value and low hydroxyl value fatty acid-modified epoxy resin is described. This fatty acid-modified epoxy resin is generally low in compatibility with a resin used in a lithographic offset printing ink, and tends to cause a decrease in gloss of a printed matter (ink film).

Patent Document 2 describes an active energy ray-curable resin composition and a printing ink composition using an alkyd resin having a low acid value and a low hydroxyl value. However, judging from the composition of the alkyd resin described in the examples of Patent Document 2, the oil length of the alkyd resin is less than 50, so even if the water resistance can be improved, a good ink It is extremely difficult to obtain fluidity and high gloss.
In general, an alkyd resin having a low oil length has a high viscosity and is inferior in pigment dispersibility. Therefore, it is known that the fluidity and gloss of an ink using the resin decrease.

JP-A-2-251579 Japanese Patent Laid-Open No. 2-238013

  An object of the present invention is to provide a resin varnish for printing ink that can provide a printing ink excellent in emulsification suitability and gloss of printed matter, and the printing ink.

  The inventors have conducted intensive research to solve the above problems, and found that a printing ink containing a varnish using an alkyd resin having an acid value and a hydroxyl value within a specific range is excellent in gloss and emulsification ability. The invention has been completed.

That is, the resin varnish for printing ink of the present invention contains an alkyd resin that satisfies both the following conditions (a) and (b).
(A) The solid content acid value is 1.5 to 5 mgKOH / g, or the solid content hydroxyl value is 5 to 15 mgKOH / g.
(B) The solid content acid value is 5 mgKOH / g or less, and the solid content hydroxyl value is 15 mgKOH / g or less.
In other words, the conditions (a) and (b) above indicate that the alkyd resin of the present invention has a solid content acid value of 5 mgKOH / g or less and a solid content hydroxyl value of 15 mgKOH / g or less. It belongs to the region excluding the region B where the partial acid value is 1.5 mg KOH / g or less and the solid content hydroxyl value is 5 mg KOH / g or less.

  The printing ink using the resin varnish for printing ink of the present invention is excellent in gloss and emulsification ability, and the varnish can be suitably used as a raw material for printing ink for offset rotary printing, sheet-fed printing and newspaper printing. is there.

The component constituting the printing ink resin varnish of the present invention is essentially an alkyd resin, and is composed of other printing ink resins and solvents.
A rosin-modified phenolic resin may be used as the printing ink resin. Moreover, as a solvent, it is preferable to use the organic solvent whose content rate of an aromatic organic solvent is 1 mass% or less.

  The alkyd resin of the present invention is obtained by subjecting animal and vegetable oils and their fatty acids, polyvalent carboxylic acids and polyhydric alcohols to a condensation reaction.

The solid content acid value and solid content hydroxyl value of the alkyd resin are determined by the blending ratio of animal and vegetable oils and their fatty acids, polycarboxylic acids and the polyhydric alcohol described below.
When the solid content acid value is larger than 5 mgKOH / g, or when the solid content hydroxyl value is larger than 15 mgKOH / g, the emulsification tends to be excessive and the emulsification suitability of the ink is poor.

On the other hand, when the solid content acid value is 1.5 mgKOH or less and the solid content hydroxyl value is 5 mgKOH / g or less, the emulsification suitability deteriorates because it becomes difficult to emulsify.
In addition, the ester bond increases and the resin has a high molecular weight, and the gloss of the film of the printing ink using it decreases. The gloss of the printing ink, that is, the gloss of the ink film printed with the ink, is important for obtaining color depth and a high-class feeling.

  The properties of the alkyd resin are affected by the type of oil used for modification and its content (oil length, unit mass%). The oil length of the alkyd resin is preferably 50 to 90 in view of the softening point of the resin, but is used in the range of 65 to 85 from the viewpoint of maintaining a good balance between the target gloss and heat setting properties. Is more preferable.

  Among the above-mentioned animal and vegetable oils and their fatty acids, exemplarily representative examples include linseed oil, soybean oil, safflower oil, Chinese paulownia oil, asami oil, enoki oil, tall oil, rice bran oil, castor oil, dehydrated Iodine values of castor oil, rapeseed oil, cottonseed oil, palm oil, fish oil, squid liver oil, and other fatty acids, dehydrated castor oil fatty acid, and high diene fatty acid (unit: mass of iodine bound to a 100 g sample (g)) Of 100 or more unsaturated fatty acids. It is also possible to use the above-mentioned various animal and vegetable oils and their unsaturated fatty acids in combination.

  Furthermore, fatty acids of the above-mentioned animal and vegetable oils, ester compounds of fatty acids and monohydric alcohols of the above-mentioned vegetable oils, polymerized oils such as linseed oils and the like, and polymer oils such as linseed oil or higher polymers may be used as animal and vegetable oils. it can. Animal and vegetable oils and their fatty acids may be used alone or in admixture of two or more.

  Specific examples of the polyvalent carboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, succinic acid, maleic acid, itaconic acid, fumaric acid, tetrahydrophthalic acid, hexahydrophthalic acid, and methyltetrahydrophthalic acid. Acid, adipic acid, sebacic acid, azelaic acid, hymic anhydride (product of Hitachi Chemical Co., Ltd., registered trademark), trimellitic acid, methylcyclohexeric carboxylic acid or pyromellitic acid, dimer acids derived from unsaturated fatty acids, Or these anhydrides etc. are mentioned, These polyhydric carboxylic acid is used individually or in mixture of 2 or more types.

  Among the polyvalent carboxylic acids, an aromatic carboxylic acid is preferable in consideration of the emulsification suitability of the ink. Further, considering the gloss of the printed matter, the isophthalic acid-derived component is 10 to 25 in 100% by mass of the alkyd resin. It is preferably contained by mass%, more preferably 18-23 mass%.

  Specific examples of the polyhydric alcohol include ethylene glycol, polyethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, polypropylene glycol, 1,3-butanediol, 2,3-butanediol, 1, 4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2,2-dialkyl Diols having an alicyclic structure such as 1,3-propanediol, 2,4,4-trimethyl-1,3-pentanediol, butylene glycol, hydrogenated bisphenol A, adducts of ethylene oxide of bisphenol A, bisphenol A's propire Dihydric alcohols such as adduct of oxide, glycerin, trimethylol ethane, trimethylol propane or pentaerythritol, tris isocyanurate.

  Moreover, you may use the polyhydric alcohol containing a carboxylic acid group as a polyhydric alcohol, and if a typical thing is illustrated, a dimethylol propionic acid, a dimethylol butanoic acid, and diphenolic acid will be mentioned.

  Animal and vegetable oils and their condensation reactions with fatty acids, polycarboxylic acids, and polyhydric alcohols can be obtained according to various known and commonly used synthetic methods. A monoglyceride method in which polyhydric carboxylic acid is condensed (esterified) after the alcohol exchange reaction of animal and vegetable oils is added together with the fatty acid, and the fatty acid, polycarboxylic acid and polyhydric alcohol of animal and vegetable oils. In general, the fatty acid method of condensing (esterifying) them together is common.

In conducting the condensation reaction as described above, in order to promote the reaction, a metal catalyst such as a tin compound, a zinc compound, or a titanium compound, or an inert solvent azeotropic with water such as xylene. May be added.

  The resin for printing ink used in the present invention is generally used as a printing ink resin such as rosin-modified phenol resin or petroleum resin-modified rosin-modified phenol resin, maleic acid-modified phenol resin, alkyd resin, unsaturated polyester, petroleum resin. It is what. Among these, rosin-modified phenol resin and petroleum resin-modified rosin-modified phenol resin are preferable.

  The rosin-modified phenol resin used in the present invention can be obtained by reacting a rosin ester resin obtained by esterifying a rosin with a polyhydric alcohol with a resol type phenol resin.

  Examples of rosins used herein include those that react with a resol type phenol resin, such as gum rosin, wood rosin, tall oil rosin, polymerized rosin, acid-modified rosin, and those purified by distillation or the like. Of these, gum rosin is preferable because it has excellent reactivity with a resol type phenol resin and a high-viscosity rosin-modified phenol resin can be obtained.

  The acid-modified rosin is preferably modified with a dibasic acid or an anhydride thereof. Examples of the dibasic acid or its anhydride include fumaric acid, maleic acid, maleic anhydride, adipic acid, itaconic acid, phthalic anhydride, isophthalic acid, terephthalic acid, and trimellitic anhydride. Acid, maleic acid and maleic anhydride are preferred.

  Examples of the polyhydric alcohol as a raw material for the rosin-modified phenol resin include, for example, glycerin, diglycerin, trimethylolethane, trimethylolpropane, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, Pentaerythritol, dipentaerythritol, sorbitol and the like can be mentioned, among which glycerin and pentaerythritol are preferable.

  Examples of the method for producing a rosin ester resin include a method in which a rosin and a polyhydric alcohol are esterified at 200 to 300 ° C., preferably 250 to 285 ° C. in the presence of an esterification catalyst. In this case, the ratio of the rosins and polyhydric alcohol used is usually preferably such that the hydroxyl group in the polyhydric alcohol is 1.5 molar equivalents or less with respect to 1 molar equivalent of the carboxylic acid in the rosins. A ratio of 8 to 1.1 molar equivalents is particularly preferred.

  As the rosin ester resin, a rosin ester resin having an acid value of 70 mgKOH / g or less is used, and among them, a rosin ester resin having an acid value of 18 mgKOH / g or less is preferable. The hydroxyl value of the rosin ester resin is preferably 50 mgKOH / g or less.

  The resol type phenolic resin used in the present invention is a condensate obtained by reacting phenols and formaldehyde in the presence of an alkali catalyst such as sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, and aqueous ammonia. In addition, a resol product of a novolac type phenol resin is preferably used.

Among these, a condensate obtained by reacting phenols (P) and formaldehyde (F) in the presence of an alkali catalyst in a range where F / P (molar ratio) is 1.5 to 3.0 is preferable.
As the average number of nuclei of these resol type phenol resins, those having an average of 1 to 10 nuclei are usually used, and among them, those having an average of 3 to 6 nuclei as the main component are preferred. As a weight average molecular weight, the thing of 200-1600 is mentioned, Especially the thing of 700-1300 is preferable.

Examples of the phenols include phenol, cresol, amylphenol, p-tertiary butylphenol, p-octylphenol, p-nonylphenol, p-dodecylphenol, bisphenol A, and among them, p-tertiarybutylphenol. Alkylphenol having a substituent having 4 to 12 carbon atoms in the para position, such as p-octylphenol, p-nonylphenol, and p-dodecylphenol.
In addition, formaldehyde includes a formaldehyde supply substance, and examples thereof include formaldehyde and rose formaldehyde.

In the resin varnish for printing ink of the present invention, the solid content mass ratio (A / B) of the alkyd resin (represented by A) and the rosin-modified phenolic resin (represented by B) is the ink tackiness, viscosity, fluidity and emulsification. From the viewpoint of suitability, it is preferably 1/35 to 20/35, more preferably 3/35 to 15/35.
When A / B is less than 1/35, the gloss of the printed matter is lowered, and when it is more than 20/35, the viscosity of the ink is lowered. To metastasize well).
The solid content of the resin refers to the non-volatile content of the resin, which is calculated by drying the resin at 108 ° C. for 1 hour in a blowing oven and measuring the mass before and after drying.

In the production of the printing ink of the present invention, it is preferable to use an organic solvent having an aromatic solvent content of 1% by mass or less.
Examples of the organic solvent having an aromatic solvent content of 1% by mass or less include Solvent No. 0 Solvent H for printing ink (manufactured by Nippon Oil Corporation, aromatic component content of 1% by mass or less), AF solvent 4 No. 7 (manufactured by Shin Nippon Oil Co., Ltd., aromatic component content 1 mass% or less) and the like.
The organic solvent preferably has a boiling point in the range of 239 to 321 ° C., and has a boiling point in the range of 260 to 300 ° C., in order to have good stability and drying on the printing press of the ink using the varnish of the present invention. The range of is more preferable. Two or more organic solvents may be used in combination.

  The aniline point of the organic solvent is preferably in the range of 63 to 94 ° C. By using an organic solvent within that range, the viscosity of the ink comprising the resin varnish for printing ink of the present invention can be set to an appropriate value, mist is hardly generated, and good drying properties and gloss are obtained.

  When manufacturing 100 mass parts of resin varnishes for printing inks of this invention, it is preferable to add 0.01-3.0 mass parts gelling agent. This makes it possible to produce a gel varnish for printing ink having higher viscoelasticity, and all steps up to the finishing of the varnish for printing ink can be carried out all at once, which is extremely economical.

  Suitable gelling agents that can be used include aluminum compounds such as aluminum alcoholate and aluminum soap, metal soaps such as manganese, cobalt and zirconium, and gelling agents such as alkanolamines.

The resin varnish for printing ink obtained in the present invention has a pigment content of 10 to 25% by mass consisting of extender pigments such as yellow, red, indigo, black and calcium carbonate, and 30 to 85% by mass of the resin varnish for printing ink of the present invention. %, The above organic solvent is 0 to 30% by mass, vegetable oils such as soybean oil and vegetable oil esters are 0 to 30% by mass, and further, if necessary, a drying inhibitor, a drier, a friction resistance improver and the like are 0.5%. A blending raw material consisting of 10% by mass to 10% by mass is mixed and kneaded with a roll mill or the like to obtain a printing ink.
Printing inks are prepared to have appropriate tackiness and viscosity, and printing inks corresponding to various uses such as sheet-fed printing inks and offset rotary printing inks can be obtained.
The resin varnish for printing ink of the present invention can also be used as a raw material for newspaper ink and letterpress ink.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited thereto. In the examples, “part” and “%” are based on mass unless otherwise specified.

First, examples and comparative examples of lithographic offset rotary printing ink will be described.
<1. Preparation of resin varnish for lithographic offset rotary printing ink>
[Preparation of rosin-modified phenolic resin varnish]
220 parts of soybean oil and 15 parts of AF Solvent No. 7 (manufactured by Nippon Oil Co., Ltd.) are added to 48 parts of rosin-modified phenolic resin (product number 1126HV, manufactured by Dainippon Ink and Chemicals, Inc.) Hold at 1 ° C. for 1 hour.
Thereafter, 15.7 parts of AF Solvent No. 7 and 1 part of ethyl acetoacetate aluminum dinormal butyrate were added and held at 160 ° C. for 1 hour. Further, BHT (2,6-di-tert-butyl-4- 0.3 parts of methylphenol) was added, and rosin-modified phenolic resin varnishes used in Examples and Comparative Examples were prepared. This rosin modified phenolic resin varnish was used in Examples 1-6 and Comparative Examples 1-5.

[Preparation of Alkyd Resin Used in Example 1 and Resin Varnish A-1 for Printing Ink]
In a reaction kettle equipped with a stirrer, rectifying column and thermometer, 780 parts of soybean oil, 35.6 parts of glycerin and 39.4 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature is lowered to 150 ° C., and a decanter separator is provided instead of the rectification column. 184.2 parts of isophthalic acid, 30 parts of xylene for reflux, and 0.2 part of dibutyltin oxide are added, and the mixture is gradually heated to 250 ° C. Then, the esterification reaction was carried out until the solid content acid value became 4, while dehydrating by holding at 250 ° C. for about 10 hours. The dehydration amount was 37.6 parts.
Next, in order to remove xylene, while maintaining a temperature of 250 ° C., a reduced pressure reaction is performed at about 30 Torr for 2 hours to obtain 990.3 parts of an alkyd resin having a solid content acid value of 2.3 and a solid content hydroxyl value of 8.0. Got.
The obtained alkyd resin and the rosin-modified phenol resin varnish were blended so that the ratio of the alkyd resin to the rosin-modified phenol resin was 5/35 to obtain a resin varnish A-1 for printing ink.

[Preparation of Alkyd Resin Used in Example 2 and Resin Varnish A-2 for Printing Ink]
In a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, 700 parts of soybean oil, 48.5 parts of glycerin, and 53.8 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. 250.8 parts of isophthalic acid and 30 parts of xylene for reflux were added, and the mixture was gradually heated to 250 ° C. While adding 2 parts and maintaining at 250 ° C. for about 8 hours for dehydration, the esterification reaction was performed until the solid content acid value became 5. The dehydration amount was 50.6 parts.
Next, in order to remove xylene, while maintaining a temperature of 250 ° C., a reduced pressure reaction is performed at about 30 Torr for 2 hours to obtain 992.4 parts of an alkyd resin having a solid content acid value of 4.0 and a solid content hydroxyl value of 12.0. Got.
The obtained alkyd resin and the rosin-modified phenolic resin varnish were blended so that the ratio of the alkyd resin to the rosin-modified phenolic resin was 5/35 to obtain a resin varnish A-2 for printing ink.

[Preparation of Alkyd Resin Used in Example 3 and Resin Varnish A-3 for Printing Ink]
Into a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, 850 parts of soybean oil, 24.6 parts of glycerin, and 27.3 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. After adding 123.9 parts of isophthalic acid and 30 parts of xylene for reflux, and gradually heating to 250 ° C., 2-ethylhexanoic acid was added. While adding 0.2 parts of zinc and maintaining at 250 ° C. for about 12 hours for dehydration, the esterification reaction was carried out until the solid content acid value reached 4. The dehydration amount was 24.1 parts.
Next, in order to remove xylene, while maintaining a temperature of 250 ° C., a reduced pressure reaction is performed at about 30 Torr for 2 hours to obtain 990.5 parts of an alkyd resin having a solid content acid value of 3.2 and a solid content hydroxyl value of 9.5. Got.
The obtained alkyd resin and rosin-modified phenolic resin varnish were blended so that the ratio of alkyd resin and rosin-modified phenolic resin was 5/35 to obtain resin varnish A-3 for printing ink.

[Preparation of Alkyd Resin Used in Example 4 and Resin Varnish A-4 for Printing Ink]
Mixing 750 parts of soybean oil, 40.0 parts of glycerin and 44.4 parts of pentaerythritol in a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, and maintaining at 250 ° C. for about 1 hour, alcohol exchange reaction Went.
The temperature is lowered to 150 ° C., and a decanter separator is provided instead of the rectification column. 157.5 parts of isophthalic acid, 46.8 parts of phthalic anhydride and 30 parts of xylene for reflux are added, and the mixture is gradually heated to 250 ° C. Then, 0.2 part of dibutyltin oxide was added, and the esterification reaction was performed until the solid content acid value became 4 while dehydrating by holding at 250 ° C. for about 8 hours. The dehydration amount was 33.6 parts.
Next, in order to remove xylene, a pressure reduction reaction was performed at about 30 Torr for 2 hours while maintaining 250 ° C., and 989.8 parts of alkyd resin having a solid content acid value of 3.5 and a solid content hydroxyl value of 8.0. Got.
The obtained alkyd resin and the rosin-modified phenolic resin varnish were blended so that the ratio of the alkyd resin to the rosin-modified phenolic resin was 5/35 to obtain a resin varnish A-4 for printing ink.

[Preparation of Alkyd Resin Used in Example 5 and Resin Varnish A-5 for Printing Ink]
750 parts of soybean oil, 44.1 parts of glycerin, and 44.1 parts of pentaerythritol are blended in a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. After adding 206 parts of isophthalic acid and 30 parts of xylene for refluxing and gradually heating to 250 ° C., 0.2 part of dibutyltin oxide was added. While adding and maintaining at 250 ° C. for about 12 hours for dehydration, the esterification reaction was performed until the solid content acid value reached 4. The amount of dehydration was 38.2 parts.
Next, in order to remove xylene, a pressure reduction reaction was performed at about 30 Torr for 3 hours while maintaining a temperature of 250 ° C., and 990.3 parts of an alkyd resin having a solid content acid value of 2.6 and a solid content hydroxyl value of 3.0. Got.
The obtained alkyd resin and the rosin-modified phenolic resin varnish were blended so that the ratio of the alkyd resin to the rosin-modified phenolic resin was 5/35 to obtain a resin varnish A-5 for printing ink.

[Preparation of Alkyd Resin Used in Example 6 and Resin Varnish for Printing Ink]
750 parts of soybean oil, 44.1 parts of glycerin, and 44.1 parts of pentaerythritol are blended in a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went. The amount of dehydration was 38.2 parts.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectifying column. After adding 206.2 parts of isophthalic acid and 30 parts of xylene for reflux, and gradually heating to 250 ° C., dibutyltin oxide 0.2 The esterification reaction was carried out until the solid content acid value was 2, while dehydrating by adding a part and maintaining at 250 ° C. for about 15 hours.
Next, in order to remove xylene, a pressure reduction reaction was performed at about 30 Torr for 3 hours while maintaining 250 ° C., and 992.3 parts of an alkyd resin having a solid content acid value of 1.0 and a solid content hydroxyl value of 6.7. Got.
The obtained alkyd resin and the rosin-modified phenol resin varnish were blended so that the ratio of the alkyd resin to the rosin-modified phenol resin was 5/35, to obtain a resin varnish A-6 for printing ink.

[Preparation of Alkyd Resin Used in Comparative Example 1 and Resin Varnish a-1 for Printing Ink]
In a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, 800 parts of soybean oil, 31.9 parts of glycerin, and 35.4 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. After adding 165.3 parts of isophthalic acid and 30 parts of xylene for refluxing, and gradually heating to 250 ° C., dibutyltin oxide 0.2 The esterification reaction was carried out until the solid content acid value was 12, while adding and dehydrating the mixture at 250 ° C. for about 5 hours. The amount of dehydration was 28.9 parts.
Next, in order to remove xylene, while maintaining a temperature of 250 ° C., a reduced pressure reaction is performed at about 30 Torr for 2 hours to obtain 991.4 parts of an alkyd resin having a solid content acid value of 10.0 and a solid content hydroxyl value of 15.0. Got.
The obtained alkyd resin and rosin-modified phenolic resin varnish were blended so that the ratio of alkyd resin and rosin-modified phenolic resin was 5/35 to obtain resin varnish a-1 for printing ink.

[Preparation of Alkyd Resin Used in Comparative Example 2 and Resin Varnish a-2 for Printing Ink]
In a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, 800 parts of soybean oil, 34.0 parts of glycerin, and 37.7 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. After adding 161.8 parts of isophthalic acid and 30 parts of xylene for reflux, and gradually heating to 250 ° C., 2-ethylhexanoic acid was added. While adding 0.2 parts of zinc and maintaining at 250 ° C. for about 8 hours for dehydration, the esterification reaction was carried out until the solid content acid value reached 6. The dehydration amount was 29.3 parts.
Next, in order to remove xylene, while maintaining a temperature of 250 ° C., a reduced pressure reaction is performed at about 30 Torr for 2 hours to obtain 990.8 parts of an alkyd resin having a solid content acid value of 4.8 and a solid content hydroxyl value of 20.0. Got.
The obtained alkyd resin and rosin-modified phenol resin varnish were blended so that the ratio of alkyd resin and rosin-modified phenol resin was 5/35, to obtain resin varnish a-2 for printing ink.

[Preparation of Resin Varnish a-3 for Printing Ink Used in Comparative Example 3]
The obtained alkyd resin and the rosin-modified phenol resin varnish were blended so that the ratio of the alkyd resin (A-1) to the rosin-modified phenol resin was 25/35, and the resin varnish for printing ink a-3 Got.

[Preparation of Alkyd Resin Used in Comparative Example 4 and Resin Varnish a-4 for Printing Ink]
Mixing 750 parts of soybean oil, 50.1 parts of glycerin and 55.5 parts of pentaerythritol in a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, and maintaining at 250 ° C. for about 1 hour, alcohol exchange reaction Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. After adding 183.9 parts of isophthalic acid and 30 parts of xylene for refluxing, and gradually heating to 250 ° C., dibutyltin oxide 0.2 The esterification reaction was carried out until the solid content acid value was 2, while adding and dehydrating the mixture at 250 ° C. for about 4 hours. The dehydration amount was 32.5 parts.
Next, in order to remove xylene, a pressure reduction reaction was performed at about 30 Torr for 2 hours while maintaining 250 ° C., and 1000.0 parts of alkyd resin having a solid content acid value of 0.7 and a solid content hydroxyl value of 48.0 Got.
To a reaction kettle equipped with a stirrer, a cooling tower and a thermometer, 1000 parts of this alkyd resin and 90 parts of acetic anhydride were added and reacted at 160 ° C. for 5 hours. Thereafter, in order to distill off acetic acid, a reduced pressure reaction was performed at a reduced pressure of about 30 Torr for 2 hours to obtain 993.3 parts of an alkyd resin having a solid content acid value of 1.1 and a solid content hydroxyl value of 1.5.
The obtained alkyd resin and rosin-modified phenolic resin varnish were blended so that the ratio of the alkyd resin to the rosin-modified phenolic resin was 5/35 to obtain a resin varnish a-4 for printing ink.

[Preparation of Alkyd Resin and Resin Varnish for Printing Ink Used in Comparative Example 5]
In a reaction kettle equipped with a stirrer, rectifying column and thermometer, 750 parts of soybean oil, 39.3 parts of glycerin, and 43.6 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour for alcohol exchange reaction. Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. After adding 122.3 parts of isophthalic acid and 30 parts of xylene for refluxing, and gradually heating to 250 ° C., dibutyltin oxide 0.2 The esterification reaction was carried out by adding 25 parts and maintaining at 250 ° C. for about 30 hours for 25 hours until the solid content acid value reached 5.
Next, in order to remove the solvent of xylene, a reduced pressure reaction was performed at about 30 Torr while maintaining 250 ° C. for 10 hours. However, since gelation occurred, the solid content acid value was 1.0 and the solid content hydroxyl value was 1.0. An alkyd resin could not be obtained. Therefore, the alkyd resin of Comparative Example 5 could not be obtained, and the printing ink could not be prepared.

<2. Preparation of lithographic offset rotary printing ink>
In the printing inks of Examples 1 to 6 and Comparative Examples 1 to 4, the raw materials having the following composition were mixed using a three-roll mill so that coarse particles in the ink had a particle size of 2.5 μm or less. In total, 10 inks were obtained.
The amount of AF-7 solvent used as an aroma-free solvent is an amount necessary for the ink to have a Raleigh viscosity of 120 dPa · s at 25 ° C.
55 parts each of the resin varnish for printing ink of A-1 to A-6 and a-1 to 4 described above.
Carmin 6B ... 20 copies.
AF-7 Solvent ... Necessary amount.
Carmine 6B is a red pigment manufactured by Dainippon Ink & Chemicals, Inc.

<3. Evaluation of lithographic offset rotary printing ink>
The evaluation of gloss and inking property was performed using a color-developed product developed using a proof bow printability tester. The color was developed so that the ink density was 1.45 at a printing pressure of 400 N and a printing speed of 6 m. Then, the 60 ° gloss of the color-extended product was measured. The evaluation criteria for gloss is 82 points or higher and less than 82 points.
In the evaluation of the fleshing property, when the color is developed by the proof bow, the case where the paper does not occur is indicated by ○, and the case where it is generated is indicated by ×.
The proof bow printing aptitude tester is a testing machine for offset printing ink developed at the FOGRA printing plate making laboratory in Germany and is widely used.

The water width was evaluated using a Roland 700 printing machine manufactured by Roland. The water width is the width of the numerical value of the scale of the water dial of the printing press that can print without causing the printed matter density to drop by 0.1 points or more and without being stained. The wider the width, the better the emulsification suitability.
Decreasing the water dial value will reduce the amount of dampening water supplied and make it more prone to contamination. Further, when the numerical value is increased, the supply amount is increased, and when the emulsification of the ink is excessive, the density of the printed matter tends to decrease. The water width evaluation criteria were an upper reference value of 82 or higher and a lower reference value of 32 or lower.

The heat set property was evaluated using a color-developed product developed on an OK top coat paper using an RI tester. Immediately after the color development, it was left in a dryer kept at 100 ° C. for 20 seconds. Then, it took out and evaluated the stickiness of the color-extracted thing by finger erosion. When there is no stickiness, heat setting property ○, when it remains somewhat, Δ, when a considerable degree of stickiness remains is marked as x.
The evaluation results of the inks of Examples 1 to 6 are shown in Table 1, and the evaluation results of Comparative Examples 1 to 4 are shown in Table 2. The ratio in the table represents the mass% of the component in the ink.
In Comparative Examples 1 to 3, the water width does not reach the standard. Moreover, it turns out that the comparative example 4 has low gloss. In Comparative Example 3, the alkyd resin is excessive with respect to the rosin-modified phenol resin, so that the inking property is lowered.

Next, examples and comparative examples of lithographic offset sheet-fed printing ink will be described.
<4. Preparation of resin varnish for lithographic offset sheet-fed printing ink>
[Preparation of rosin-modified phenolic resin varnish]
To 40 parts of rosin-modified phenolic resin (product number 1126HV, manufactured by Dainippon Ink and Chemicals, Inc.), 35 parts of soybean oil and 15 parts of AF Solvent No. 6 (manufactured by Shin Nippon Oil Co., Ltd.) were added to obtain 220 parts. Hold at 1 ° C. for 1 hour.
Thereafter, 9.9 parts of AF Solvent No. 6 and 1 part of ethyl acetoacetate aluminum dinormal butyrate were added and held at 160 ° C. for 1 hour. Further, BHT (2,6-di-tert-butyl-4- Methylphenol) 0.1 part was added, and the rosin modified phenolic resin varnish used in Examples and Comparative Examples was prepared. This rosin-modified phenolic resin varnish was used in Example 7 and Comparative Examples 6-7.

[Preparation of Alkyd Resin Used in Example 7 and Resin Varnish A-7 for Printing Ink]
In a reaction kettle equipped with a stirrer, rectifying column and thermometer, 780 parts of soybean oil, 35.6 parts of glycerin and 39.4 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature is lowered to 150 ° C., and a decanter separator is provided instead of the rectification column. 184.2 parts of isophthalic acid, 30 parts of xylene for reflux, and 0.2 part of dibutyltin oxide are added, and the mixture is gradually heated to 250 ° C. Then, the esterification reaction was carried out until the solid content acid value became 4, while dehydrating by holding at 250 ° C. for about 10 hours. The dehydration amount was 37.6 parts.
Next, in order to remove xylene, while maintaining a temperature of 250 ° C., a reduced pressure reaction is performed at about 30 Torr for 2 hours to obtain 990.3 parts of an alkyd resin having a solid content acid value of 2.3 and a solid content hydroxyl value of 8.0. Got.
The obtained alkyd resin and the rosin-modified phenolic resin varnish were blended so that the ratio of the alkyd resin to the rosin-modified phenolic resin was 5/35 to obtain a resin varnish A-7 for printing ink.

[Preparation of Alkyd Resin Used in Comparative Example 6 and Resin Varnish a-6 for Printing Ink]
In a reaction kettle equipped with a stirrer, a rectifying column and a thermometer, 800 parts of soybean oil, 31.9 parts of glycerin, and 35.4 parts of pentaerythritol are blended and kept at 250 ° C. for about 1 hour to perform an alcohol exchange reaction. Went.
The temperature was lowered to 150 ° C., and a decanter separator was provided instead of the rectification column. After adding 165.3 parts of isophthalic acid and 30 parts of xylene for refluxing, and gradually heating to 250 ° C., dibutyltin oxide 0.2 The esterification reaction was carried out until the solid content acid value was 12, while adding and dehydrating the mixture at 250 ° C. for about 5 hours. The amount of dehydration was 28.9 parts.
Next, in order to remove xylene, while maintaining a temperature of 250 ° C., a reduced pressure reaction is performed at about 30 Torr for 2 hours to obtain 991.4 parts of an alkyd resin having a solid content acid value of 10.0 and a solid content hydroxyl value of 15.0. Got.
The obtained alkyd resin and rosin-modified phenol resin varnish were blended so that the ratio of alkyd resin and rosin-modified phenol resin was 5/35, to obtain resin varnish a-6 for printing ink.

[Preparation of Resin Varnish a-7 for Printing Ink Used in Comparative Example 7]
The alkyd resin A-7 and rosin-modified phenol resin were blended so that the ratio was 25/35 to obtain a resin varnish a-7 for printing ink.

<5. Preparation of lithographic offset sheet-fed printing ink>
The total of three printing inks of Example 7 and Comparative Examples 6 to 7 are blended as shown below, using a three-roll mill so that the particle size of coarse particles in the ink is 2.5 μm or less. Obtained by dispersing the meat.
55 parts each of the resin varnish for printing ink of A-7 and a-5 to 6 described above.
Carmin 6B ... 20 copies.
AF-6 Solvent ... Required amount.
Note that the amount of AF-6 solvent used as an aroma-free solvent is an amount necessary for the ink to have a Raleigh viscosity of 180 dPa · s at 25 ° C.

<6. Evaluation of flat offset sheet-fed printing ink>
The gloss, water width, and inking property test methods and evaluation criteria are in accordance with the evaluation methods for the offset rotary printing ink.
An evaluation of room temperature setting was performed using an automatic setting tester. Using an RI tester, color is applied to an OK top coat paper with an ink level of 0.125 cc, and immediately after color development, it is set on an automatic setting tester together with a test fine paper. The evaluation criteria for room temperature setting property are those that do not set for more than 15 minutes.
Table 3 shows the evaluation results of the inks of Example 7 and Comparative Examples 6-7. The ratio in the table represents the mass% of the component in the ink.
In Comparative Examples 6 and 7, the water width does not reach the standard. In Comparative Example 7, the alkyd resin is excessive with respect to the rosin-modified phenol resin, so that the inking property is lowered.

  The printing ink using the resin varnish for printing ink of the present invention is excellent in gloss and emulsification ability, and the varnish can be suitably used as a raw material for printing ink for offset rotary printing, sheet-fed printing and newspaper printing. .

Claims (6)

A printing ink resin varnish containing an alkyd resin having a solid content acid value of 1.5 to 5 mg KOH / g and a solid content hydroxyl value of 5 mg or more and less than 15 mg KOH / g, and a rosin-modified phenol resin, Resin varnish for printing ink , wherein mass ratio of resin to rosin modified phenolic resin (= (solid content of alkyd resin) / (solid content of rosin modified phenolic resin)) is 1/35 to 20/35 .   The resin varnish for printing ink according to claim 1, wherein the alkyd resin is an alkyd resin having an oil length of 50 to 90.   The resin varnish for printing ink according to claim 1, wherein the alkyd resin is an alkyd resin containing an isophthalic acid-derived component.   The resin varnish for printing ink according to claim 3, wherein the content of the isophthalic acid-derived component of the alkyd resin is 10 to 25% by mass.   The resin varnish for printing ink according to claim 3, wherein the alkyd resin is an alkyd resin obtained by reacting an animal and vegetable oil having an iodine value of 100 or more, a polyvalent carboxylic acid containing isophthalic acid, and a polyhydric alcohol. . A printing ink comprising the resin varnish for printing ink according to any one of claims 1 to 5 .