JP2015189894A - Resin for lithographic printing ink and lithographic printing ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excellent printing ink that shows stable printing workability and concentration stability under printing conditions with excessive supply of dampening water, and that prevents watermarks or roller stripping.SOLUTION: A lithographic printing ink is provided, which contains the following rosin-modified phenolic resin (A). The rosin-modified phenolic resin (A) is produced by reacting rosin (a) and a resol type phenolic resin (b), then reacting a polyhydric alcohol (c). In the above production method of the rosin-modified phenolic resin (A), the polyhydric alcohol is divided into two or more fractions to separately react. With respect to the total amount of the polyhydric alcohol (c) supplied, an amount of the polyhydric alcohol (c) subjected to the reaction at the second time and later is 5 to 40 wt.%.

Description

  The present invention relates to a new and useful lithographic printing ink and printed matter. More specifically, the present invention relates to a printing ink and printed matter that are suitably used for offset lithographic printing such as newspaper printing, sheet-fed printing, and off-wheel printing, which are excellent in printability.

In recent years, in the printing industry, demands for labor saving, labor saving, automation, and high speed during printing have increased, and in particular, the printing speed has been increasingly increased. In addition, there is a demand for a printing ink that can obtain a high-quality printed matter stably for a long time without any trouble under various printing conditions, and ink manufacturers have made various improvements.

  The lithographic printing ink is an ink having a relatively high viscosity of about 10 to 100 Pa · s. The mechanism of the lithographic printing machine is that ink is supplied from the ink fountain of the printing machine via a plurality of rollers to the image area on the printing plate, dampening water is supplied to the non-image area in printing with water, and non-printing in waterless printing. The image area is made of a silicon layer, and the ink is repelled to form an image on the paper.

In printing with offset water, ink is supplied from the ink fountain to the plate surface via a plurality of rollers, and dampening water is supplied from the water boat to the plate surface via a plurality of rollers. Since the image area on the printing plate is oleophilic, ink is accepted, and since the non-image area on the printing plate is hydrophilic, an image is formed on the paper surface by coating with dampening water. If the amount of ink supplied and the amount of dampening water supplied are imbalanced, printing trouble may occur. For example, if dampening water is insufficient in the non-image area of the printing plate, a piling phenomenon generally referred to as non-image area remains. Further, when dampening water is supplied excessively, serious printing troubles such as water rod entanglement, water eyes, density fluctuation, flying, remaining roller, and roller peeling are induced. In order to prevent these printing troubles and to reproduce an excellent printing paper surface, the emulsification state of the ink and the dampening water on the printing machine is controlled, and the water width (the dampening water is applied to the printing machine or the paper surface). It is necessary to design a prescription for printing ink that expands the range of the amount of rising water that does not cause trouble. In recent years, with the progress of high-speed printing accompanying the improvement in the performance of offset printing presses, the ratio of waste paper used for printing paper has increased, so the supply and demand balance of ink and fountain solution has changed, and an optimal and stable emulsification state It is difficult to hold.

In particular, in printing with a small number of patterns, the amount of dampening water supplied tends to be excessive with respect to the amount of ink supplied. If the ink does not receive a large amount of dampening water inside, the dampening water that could not be received inside will be on the surface. It appears on the surface of the ink as water and inhibits smooth transfer of the ink between the rollers. In such a case, it is necessary to design an ink that can receive a large amount of fountain solution, and it is usual to achieve the target emulsification rate of the ink by using a surfactant. When an ink with a high emulsification rate is made with an agent or the like, background stain is induced in the non-image area of the plate, and generally a low surface tension cationic surfactant / anionic surfactant / amphoteric surfactant / nonionic surfactant If ink is used, the ink surface tension is remarkably lowered and the ink is easily scattered in the fountain solution, which causes troubles such as scattering stains and metering entanglements (Patent Documents 1 to 3).

JP 2007-31477 A JP 2007-169465 A JP 11-349880 A

The present invention has been made to solve such problems in the prior art, and the problem is that stable printing workability and density even under printing conditions in which dampening water is excessively supplied. In addition to providing stability, the present invention provides an excellent printing ink that is free from water and roller peeling.

  As a result of investigations aimed at solving the current problems, the present inventors have changed the structure of a relatively high molecular weight ink resin without using a low molecular weight additive such as a surfactant. In addition to suppressing the occurrence of background stains in non-image areas, density fluctuations and water droplets do not occur even in situations where overemulsification of ink is likely to occur, such as when printing extremely small patterns, greatly reducing printing trouble and excellent It was found that the printing workability was realized.

That is, the present invention. In the method for producing a rosin-modified phenol resin (A) obtained by reacting a rosin (a) and a resol type phenol resin (b) and then reacting with a polyhydric alcohol (c), the following (1), (2) To a process for producing a rosin-modified phenolic resin (A).
(1) The polyhydric alcohol is allowed to react by being divided into two or more times.
(2) Polyhydric alcohol (c2) is 5 to 40% by weight based on the total charged amount of polyhydric alcohol (c).
However, the polyhydric alcohol reacted for the first time is polyhydric alcohol (c1),
The polyhydric alcohol that is reacted after the second time is referred to as polyhydric alcohol (c2).

Furthermore, in the present invention, when the polyhydric alcohol (c2) is reacted, the acid value of the rosin-modified phenol resin intermediate (M) is 60 or less, The method for producing the rosin-modified phenol resin (A), About.
However, the rosin-modified phenol resin obtained by reacting the rosin (a) and the resole-type phenol resin (b) and then reacting with the polyhydric alcohol (c1) is referred to as a rosin-modified phenol resin intermediate (M).

Furthermore, the present invention relates to a rosin-modified phenol resin (A) produced by the above production method.

Furthermore, this invention relates to the lithographic printing ink characterized by containing the said rosin modified phenol resin (A).

Furthermore, this invention relates to the printed matter formed by printing the said lithographic printing ink on a base material.

  By using the rosin-modified phenolic resin (A) of the present invention, it is possible to suppress the occurrence of scumming in the non-image area, and in the situation where ink is easily over-emulsified such as when printing a very small pattern, the density fluctuations, water grain, etc. Can reduce printing troubles and achieve excellent printing workability.

  First, the rosin modified phenolic resin (A) of the present invention will be described. The rosin-modified phenolic resin (A) is a method for producing a rosin-modified phenolic resin obtained by reacting a rosin (a), a resole-type phenolic resin (b) and a polyhydric alcohol (c). It can be obtained by dividing the reaction into two.

  As the rosins (a) in the present invention, natural rosins such as gum rosin, wood rosin, tall oil rosin, polymerized rosin derived from the natural rosin, stable rosin obtained by disproportionation or hydrogenation of natural rosin or polymerized rosin And an unsaturated acid-modified rosin obtained by adding an unsaturated carboxylic acid to a natural rosin or a polymerized rosin. The unsaturated acid-modified rosin is, for example, maleic acid-modified rosin, maleic anhydride-modified rosin, fumaric acid-modified rosin, itaconic acid-modified rosin, crotonic acid-modified rosin, cinnamic acid-modified rosin, acrylic acid-modified rosin, methacrylic acid Examples thereof include modified rosin and acid-modified polymerized rosin corresponding thereto. These may be used alone or in combination of two or more.

The resol type phenol resin (b) is a resin obtained by reacting aldehydes and phenols in the presence of an alkaline catalyst. 1.0-4.0 mol is preferable with respect to 1 mol of phenols, More preferably, it is 1.5-3.0 mol. As the alkaline catalyst, metal hydroxide catalysts such as sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, and organic amines can be used. The reaction is carried out at 60 to 120 ° C. under normal pressure or pressure. As phenols, all aromatic compounds having a phenolic hydroxyl group can be used, such as carboxylic acid, cresol, 4-amylphenol, bisphenol A, pt-butylphenol, pt-octylphenol, p-nonylphenol, and p-dodecylphenol. P-alkyl-substituted phenols are preferred. Examples of aldehydes include formaldehyde and paraformaldehyde.

  More preferably, the alkyl chain of the alkylphenol is a C4 to C13 alkylphenol. In the case of a resin produced with C4 or higher, compatibility with the ink solvent is improved, and it is suitable for the fluidity of the ink. In addition, since it is easy to form a resin having a bulk structure at C13 or less, the elasticity of the ink is improved, and the occurrence of stains and misting during printing can be suppressed.

  Although it does not specifically limit as polyhydric alcohol (c) of this invention, 1, 2- ethanediol, 1, 2- propanediol, 1, 3- propanediol which is a linear alkylene dihydric alcohol as a dihydric alcohol. 1,2-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,2-octanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, 1 , 12-dodecanediol, 1,2-dodecanediol, 1,14-tetradecanediol, 1,2-tetradecanediol, 1, 6-hexadecanediol, 1,2-hexadecanediol and the like are branched alkylene dihydric alcohols such as 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-2- Propyl-1,3-propanediol, 2,4-dimethyl-2,4-dimethylpentanediol, 2,2-diethyl-1,3-propanediol, 2,2,4-trimethyl-1,3- Pentanediol, dimethyloloctane, 2-ethyl-1,3-hexanediol, 2,5-dimethyl-2,5-hexanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl- 1,2-cyclohexa, in which 1,3-propanediol, 2,4-diethyl-1,5-pentanediol and the like are cyclic alkylene dihydric alcohols Diol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,2-cycloheptanediol, tricyclodecane dimethanol, hydrogenated catechol, hydrogenated resorcin, hydrogenated hydroquinone and the like, and polyethylene glycol (n = Examples thereof include polyether polyols such as 2 to 20), polypropylene glycol (n = 2 to 20), and polytetramethylene glycol (n = 2 to 20), polyester polyols, and the like.

  Furthermore, as trihydric or higher alcohol, glycerin, trimethylolpropane, pentaerythritol, 1,2,6-hexanetriol, 3-methylpentane-1,3,5-triol, hydroxymethylhexanediol, trimethyloloctane, Examples include diglycerin, ditrimethylolpropane, dipentaerythritol, sorbitol, inositol, tripentaerythritol and the like.

In the present invention, the polyhydric alcohol (c) needs to be divided and reacted in two or more times. In the case where the reaction is not performed after being divided into two or more at a ratio described later, there is a problem that density fluctuations, water spots, and the like are likely to occur in a situation where over-emulsification of the ink is likely to occur, such as when printing a very small pattern.
Hereinafter, the polyhydric alcohol to be reacted for the first time is referred to as polyhydric alcohol (c1), and the polyhydric alcohol to be reacted for the second time and thereafter is referred to as polyhydric alcohol (c2).

Examples of the reaction mechanism of the rosin-modified phenol resin (A) include the following reaction mechanisms.
The rosin (a) is heated and melted, and the resol type phenol resin (b) is dropped in the range of 150 to 250 ° C., and reacted for 1 to 8 hours. Next, a polyhydric alcohol (c1) is added and reacted in the range of 200 to 280 ° C. for 1 to 10 hours to obtain a rosin-modified phenol resin intermediate (M).
Furthermore, polyhydric alcohol (c2) is additionally added to the rosin-modified phenol resin intermediate (M), and the reaction is carried out in the range of 200 to 280 ° C. for 1 to 10 hours to obtain the rosin-modified phenol resin (A). . In addition, a polyhydric alcohol (c2) may be added in multiple times.

  The addition amount of the polyhydric alcohol (c2) is 5 to 40% by weight with respect to the total charged amount of the polyhydric alcohol (c) (the total amount of the polyhydric alcohol (c1) and the polyhydric alcohol (c2)). is necessary. If the amount is less than 5% by weight, the effect of the invention when the entire amount is charged at the first time is not seen, and it is likely that density fluctuations, water spots, etc. are likely to occur in situations where ink is easily over-emulsified, such as when printing a very small pattern. A malfunction occurs. On the other hand, if it exceeds 40% by weight, the amount of emulsification when ink is used becomes remarkably high, and the stain resistance of the non-image area is poor. It is presumed that the polyhydric alcohol (c2) is unevenly distributed outside the resin structure and has a suitable influence on the emulsifying properties of the ink.

  Further, the dropping timing of the polyhydric alcohol (c2) is preferably when the acid value of the rosin-modified phenol resin intermediate (M) is 60 mgKOH / g or less, more preferably 40 gKOH / g or less. Even if polyhydric alcohol (c) is added while the acid value is high, the effect of the invention when the whole amount is charged at the first time is not seen, and the concentration is high in the situation where over-emulsification of ink is likely to occur such as when printing a very small pattern. There is a problem that fluctuations and water droplets are likely to occur.

  The polyhydric alcohol (c1) and the polyhydric alcohol (c) do not need to be the same compound. Selection can be made in a timely manner according to individual required physical properties.

  In these reactions, a catalyst can be used as necessary. Catalysts include organic sulfonic acids such as benzenesulfonic acid, p-toluenesulfonic acid, p-dodecylbenzenesulfonic acid, methanesulfonic acid and ethanesulfonic acid, mineral acids such as sulfuric acid and hydrochloric acid, trifluoromethyl sulfuric acid, and trifluoromethylacetic acid. Etc. can be illustrated. Furthermore, metal complexes such as tetrabutyl zirconate and tetraisobutyl titanate, metal salt catalysts such as magnesium oxide, magnesium hydroxide, magnesium acetate, calcium oxide, calcium hydroxide, calcium acetate, zinc oxide, and zinc acetate can also be used. is there. These catalysts are usually used in the range of 0.01 to 5% by weight in the total resin. In order to suppress coloring of the resin due to the use of a catalyst, hypophosphorous acid, triphenyl phosphite, triphenyl phosphate, triphenyl phosphine, etc. may be used in combination.

  The rosin-modified phenol resin (A) obtained by the above reaction preferably has a weight average molecular weight (Mw) of 5,000 to 300,000, an acid value of 35 or less, and a melting point of 140 ° C. or more. If it is this range, it is suitable at the point of the printability of offset printing.

The weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC). Specifically, it was measured under the conditions of solvent tetrahydrofuran in terms of polystyrene using gel permeation chromatography (GPC) HLC8220 manufactured by Tosoh Corporation.

The acid value was measured according to JIS K2501-2003.
The melting point was measured according to JIS K0064-1992.

Next, the usage form as a lithographic printing ink in the present invention will be described. The lithographic printing ink in the present invention is used in the form of, for example, sheet-fed ink, heat-set rotary ink, newspaper ink (cold-set rotary ink) or the like. In general, the following compositions can be exemplified.
5-30% by weight of pigment
Rosin modified phenolic resin (A) Varnish 35-70 wt%
Other resins 0 to 30% by weight
Hydrocarbon solvent 0-60% by weight
Vegetable oil 0-70% by weight
Drying accelerator 0 to 5% by weight
Other Additives When used as a 0-10 wt% VOC free type ink, the hydrocarbon solvent is 0 wt% in the above composition. At this time, the fatty acid monoester compound may be contained in an amount of 0 to 60% by weight as necessary.

  The rosin-modified phenolic resin (A) obtained by the present invention is used as a varnish prepared by dissolving in a vegetable oil and / or a hydrocarbon solvent and / or a fatty acid monoester. It is also possible to add a gelling agent to impart elasticity and use it as a gel varnish with a crosslinked structure in the resin skeleton. As the gelling agent, a metal complex is generally used, and an aluminum complex compound can be given as a typical compound. Examples of such aluminum complex compounds include cyclic aluminum compounds such as cyclic aluminum oxide stearate (Kawaken Fine Chemical: Algomer 1000S), and aluminum alcoholates such as aluminum ethylate and aluminum isopropylate (Kawaken Fine Chemical: AIPD). , Aluminum-sec-butyrate (Kawaken Fine Chemical: ASPD), aluminum isopropylate-mono-sec-butyrate (Kawaken Fine Chemical: AMD), etc., aluminum alkyl acetates such as aluminum-di-n-butoxide-ethyl acetoacetate ( Hope Pharmaceutical: Chelope-A1-EB2), Aluminum-di-n-butoxide-methylacetoacetate (Hope Pharmaceutical: Che ope-A1-MB2), aluminum-di-iso-butoxide-methyl acetoacetate (Hope Pharmaceutical: Chelope-A1-MB12), aluminum-di-iso-butoxide-ethyl acetoacetate (Hope Pharmaceutical: Chelope-A1-EB102) Aluminum-di-iso-propoxide-ethyl acetoacetate (Hope Pharmaceutical: Chelope-A1-EP12, Kawaken Fine Chemical: ALCH), Aluminum-Tris (ethyl acetoacetate) (Kawaken Fine Chemical: ALCH-TR), Aluminum-Tris (Acetylacetonate) (Kawaken Fine Chemical: Aluminum Chelate-A), Aluminum-Bis (ethylacetoacetate) -Monoacetylacetonate (Kawaken Fine Chemical: A Mikireto D) or the like, aluminum soaps such as aluminum stearate (NOF Corporation), aluminum oleate, aluminum naphthenate, can be mentioned aluminum laurate, and aluminum acetylacetonate and the like. These gelling agents are usually used in the range of 0.1 to 10% by weight with respect to 100 parts by weight of the varnish, and are reacted at 160 to 270 ° C. under a nitrogen stream.

  As other resins, in addition to the rosin-modified phenolic resin (A) of the present invention obtained by the method described above, a binder resin can be blended, and lithographic printing inks such as rosin-modified alkyds, fatty acid-modified alkyds, petroleum resins, and polyesters. If it is resin applied to, it can be used individually or in combination of 2 or more types.

  Examples of the pigment include inorganic pigments and organic pigments. Inorganic pigments such as yellow lead, zinc yellow, bitumen, barium sulfate, cadmium red, titanium oxide, zinc white, alumina white, calcium carbonate, ultramarine, carbon black, graphite, aluminum powder, bengara, etc. -Soluble azo pigments such as naphthol, β-oxynaphthoic acid, β-oxynaphthoic acid allylide, acetoacetyl allylide, pyrazolone, β-naphthol, β-oxynaphthoic acid allylide, acetoacetyl allylide Insoluble azo pigments such as monoazo, allyl acetoacetate disazo, pyrazolone, phthalocyanine pigments such as copper phthalocyanine blue, halogenated (chlorine or brominated) copper phthalocyanine blue, sulfonated copper phthalocyanine blue, metal-free phthalocyanine, quinacridone , Dioxazine , Selenium (pyrantron, anthanthrone, indanthrone, anthrapyrimidine, flavantron, thioindigo, anthraquinone, perinone, perylene, etc.), isoindolinone, metal complex, quinophthalone, etc. In addition, various publicly known pigments such as heterocyclic pigments can be used.

  As the hydrocarbon solvent, a naphthene hydrocarbon solvent and / or a paraffin hydrocarbon solvent are preferable. A naphthenic hydrocarbon solvent and / or a paraffinic hydrocarbon solvent is a so-called aromaless (free) solvent. Commercially, AF Solvents 4-7, 0 Solvent H manufactured by JX Nippon Oil & Energy Idemitsu Kosan Co., Ltd. Supersol LA35, LA38, etc. Exxon Chemical Exxol D80, D110, D120, D130, D160, D100K, D120K, D130K etc., Riki Chemical D-SOL280, D-SOL300 However, the present invention is not limited to these examples, and these can be mixed and used at an arbitrary weight ratio. Particularly preferred are those having an aniline point in the range of 60 ° C to 110 ° C. When the aniline point is higher than 110 ° C., the solubility with the resin of the present invention is poor, the fluidity when used as an offset ink is insufficient, the ink transfer on the printing press is inferior, and transfer failure occurs, Later leveling on the printing medium is insufficient, which causes poor gloss. On the other hand, when the aniline point is lower than 60 ° C., the solvent releasability from the ink film after printing is deteriorated, resulting in poor drying, which causes blocking, show-through, and the like.

  Vegetable oil is triglyceride in which at least one fatty acid has at least one carbon-carbon unsaturated bond in triglyceride of glycerin and fatty acid. If a suitable vegetable oil is mentioned, the vegetable oil whose iodine value is at least 100 or more is preferable, and also the vegetable oil whose iodine value is 120 or more is more preferable. By setting the iodine value to 120 or more, the drying property by oxidative polymerization of the ink film can be enhanced, and it is particularly effective for a sheet-fed printing method that does not use a hot air dryer. Examples are: Asa seed oil, flaxseed oil, eno oil, prickly oil, olive oil, cacao oil, kapok oil, kaya oil, mustard oil, kyounin oil, kiri oil, kukui oil, walnut oil, poppy oil, sesame oil, safflower oil , Japanese radish seed oil, soybean oil, daikon oil, camellia oil, corn oil, rapeseed oil, niger oil, nuka oil, palm oil, castor oil, sunflower oil, grape seed oil, gentian oil, pine seed oil, cottonseed oil, palm Oil, peanut oil, dehydrated castor oil, and the like.

  Next, as a drying accelerator, acetic acid, propionic acid, butyric acid, isopentanoic acid, hexanoic acid, 2-ethylbutyric acid, naphthenic acid, octylic acid, nonanoic acid, decanoic acid, 2-ethylhexanoic acid, isooctanoic acid, isononanoic acid, Lauric acid, palmitic acid, stearic acid, oleic acid, linoleic acid, neodecanoic acid, versatic acid, secanoic acid, tall oil fatty acid, linseed oil fatty acid, soybean oil fatty acid, dimethylhexanoic acid, 3,5,5-trimethylhexa Metal salts of organic carboxylic acids such as noic acid and dimethyloctanoic acid, such as calcium, cobalt, lead, iron, manganese, zinc and zirconium salts, can be used as well as publicly known compounds. In order to accelerate curing, a plurality of these can be used in combination as appropriate.

  Furthermore, other additives can be used in the planographic printing ink of the present invention as necessary. For example, anti-friction agent, anti-blocking agent, slip agent, anti-scratch agent include natural wax such as carnauba wax, wood wax, lanolin, montan wax, paraffin wax, microcrystalline wax, Fischer Trops wax, polyethylene wax, polypropylene Synthetic waxes such as wax, polytetrafluoroethylene wax, polyamide wax, and silicone compound can be exemplified. Further, examples of the anti-skinning agent include phenols such as cresol, guaiacol, o-isopropylphenol, and oximes such as butyraloxime, methylethylketoxime, and cyclohexanone oxime.

  As a method for producing the lithographic printing ink of the present invention, a part of the pigment and the resin varnish is kneaded and dispersed with a kneader, a three-roller, an attritor, a sand mill, or the like between room temperature and 100 ° C. Next, the remaining ink components are mixed and adjusted with a three roll, gate mixer or the like.

In the present invention, as the substrate, paper used for lithographic printing can be used without any particular limitation. Specifically, coated paper such as art paper, coated paper, cast paper, high quality paper, medium quality paper, uncoated paper such as newspaper paper, and synthetic paper such as YUPO are selected.

  Next, the present invention will be described in detail with specific examples. In the examples, “parts” and “%” refer to parts by weight and% by weight unless otherwise specified. The particle size of the base ink was measured with a grindometer according to JIS-K5600-2-5. The tack of the ink was measured with a roll temperature of 30 ° C., 400 rpm, and 1 minute after using an incometer manufactured by Toyo Seiki Co., Ltd.

(Resol type phenol resin production example 1) (b1)
In the same apparatus as in Phenol Resin Production Example 1, 1500 parts of paraoctylphenol, 500 parts of 92% paraformaldehyde, 8 parts of sodium hydroxide, and 1306 parts of xylene were heated and heated while blowing nitrogen gas at 90 ° C. for 5 hours. Reacted. After cooling to 50 ° C., 10 parts of sulfuric acid was added and the mixture was allowed to stand after neutralization and stirring. After removing the aqueous layer, a resol type phenolic resin (b1) having an active ingredient of 60% was obtained.

(Rosinphenol resin production example 1) (A1)
After heating 600 parts of Chinese rosin X (Chinese gum rosin manufactured by Arakawa Chemical Industries, Ltd.) to 200 ° C. while blowing nitrogen gas into a four-necked flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, resole phenol 400 parts (as an active ingredient) of the phenol resin (b1) obtained in Resin Production Example 1 was added dropwise over 5 hours. Further, 37 parts of glycerin and 2 parts of calcium hydroxide as a catalyst were added and reacted at 255 ° C. until the acid value reached 40 (rosin phenol resin intermediate (M1)). Thereafter, 23 parts of glycerin was added and reacted until the acid value reached 25 to obtain a rosin phenol resin (A1) having a weight average molecular weight (Mw) of 30000.

(Rosin phenol resin production example 2) (A2)
After heating 600 parts of Chinese rosin X (Chinese gum rosin manufactured by Arakawa Chemical Industries, Ltd.) to 200 ° C. while blowing nitrogen gas into a four-necked flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, resole phenol 400 parts (as an active ingredient) of the phenol resin (b1) obtained in Resin Production Example 1 was added dropwise over 5 hours. Further, 55 parts of glycerin and 2 parts of calcium hydroxide as a catalyst were added and reacted at 255 ° C. until the acid value became 35 (rosin phenol resin intermediate (M2)). Thereafter, 5 parts of glycerin was added and reacted until the acid value reached 25 to obtain a rosin phenol resin (A2) having a weight average molecular weight (Mw) of 30000.

(Rosin phenol resin production example 3) (A3)
After heating 600 parts of Chinese rosin X (Chinese gum rosin manufactured by Arakawa Chemical Industries, Ltd.) to 200 ° C. while blowing nitrogen gas into a four-necked flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, resole phenol 400 parts (as an active ingredient) of the phenol resin (b1) obtained in Resin Production Example 1 was added dropwise over 5 hours. Further, 48 parts of glycerin and 2 parts of calcium hydroxide as a catalyst were added and reacted at 255 ° C. until the acid value became 35 (rosin phenol resin intermediate (M3)). Thereafter, 12 parts of glycerin was added and reacted until the acid value reached 25 to obtain a rosin phenol resin (A3) having a weight average molecular weight (Mw) of 30000.

(Rosin phenol resin production example 4) (A4)
After heating 600 parts of Chinese rosin X (Chinese gum rosin manufactured by Arakawa Chemical Industries, Ltd.) to 200 ° C. while blowing nitrogen gas into a four-necked flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, resole phenol 400 parts (as an active ingredient) of the phenol resin (b1) obtained in Resin Production Example 1 was added dropwise over 5 hours. Further, 48 parts of glycerin and 2 parts of calcium hydroxide as a catalyst were added and reacted at 255 ° C. until the acid value became 55 (rosin phenol resin intermediate (M4)). Thereafter, 12 parts of glycerin was added and reacted until the acid value reached 25 to obtain a rosin phenol resin (A4) having a weight average molecular weight (Mw) of 30000.

(Rosin phenol resin production example 5) (A5)
After heating 600 parts of Chinese rosin X (Chinese gum rosin manufactured by Arakawa Chemical Industries, Ltd.) to 200 ° C. while blowing nitrogen gas into a four-necked flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, resole phenol 400 parts (as an active ingredient) of the phenol resin (b1) obtained in Resin Production Example 1 was added dropwise over 5 hours. Further, 48 parts of glycerin and 2 parts of calcium hydroxide as a catalyst were added and reacted at 255 ° C. until the acid value reached 65 (rosin phenol resin intermediate (M5)). Thereafter, 12 parts of glycerin was added and reacted until the acid value reached 25 to obtain a rosin phenol resin (A5) having a weight average molecular weight (Mw) of 30000.

(Rosinphenol resin production example 6) (A6)
After heating 600 parts of Chinese rosin X (Chinese gum rosin manufactured by Arakawa Chemical Industries, Ltd.) to 200 ° C. while blowing nitrogen gas into a four-necked flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, resole phenol 400 parts (as an active ingredient) of the phenol resin (b1) obtained in Resin Production Example 1 was added dropwise over 5 hours. Further, 60 parts of glycerin and 2 parts of calcium hydroxide as a catalyst were added and reacted at 255 ° C. until the acid value became 25, to obtain a rosin phenol resin (A6) having a weight average molecular weight (Mw) of 30000.

(Rosin phenol resin production example 7) (A7)
After heating 600 parts of Chinese rosin X (Chinese gum rosin manufactured by Arakawa Chemical Industries, Ltd.) to 200 ° C. while blowing nitrogen gas into a four-necked flask equipped with a stirrer, a reflux condenser with a water separator, and a thermometer, resole phenol 400 parts (as an active ingredient) of the phenol resin (b1) obtained in Resin Production Example 1 was added dropwise over 5 hours. Furthermore, 58 parts of glycerin and 2 parts of calcium hydroxide as a catalyst were added and reacted at 255 ° C. until the acid value reached 40. Thereafter, 2 parts of glycerin was added and reacted until the acid value reached 25 to obtain a rosin phenol resin (A7) having a weight average molecular weight (Mw) of 30000.

[Manufacture of varnish]
In the same apparatus as in rosin phenol resin production example 1, 430 parts of rosin phenol resin (A1) obtained in rosin phenol resin production example 1, 300 parts of soybean oil, AF Solvent No. 5 (Aroma-free, manufactured by JX Nippon Oil & Energy Corporation) 260 parts of a hydrocarbon solvent and 10 parts of ALCH (a gelling agent manufactured by Kawaken Fine Chemical Co., Ltd.) were charged and reacted at 190 ° C. for 1 hour under a nitrogen stream to obtain a varnish (V1).
Varnishes (V2) to (V7) were obtained in the same manner as varnish (V1) except that rosin-modified phenolic resin (A1) was changed to rosin-modified phenolic resins (A2) to (A7).

[Example 1]
200 parts of Mitsubishi Carbon MA7 (Mitsubishi Chemical Corporation), 600 parts of varnish (V1) and 200 parts of AF solvent are kneaded using three rolls with a roll temperature of 60 ° C. until the particle size becomes 7.5 microns or less. A lithographic printing ink (X1) was obtained.

[Examples 2 to 5, Comparative Examples 1 and 2]
Lithographic printing inks (X2) to (X7) having a particle size of 7.5 microns or less (Example) except that the varnish (V1) was changed to varnishes (V2) to (V7) in the same manner as in Example 1. 2 to 5 and Comparative Examples 1 and 2) were obtained.

(Evaluation of ink)
Using the inks obtained in Examples 1 to 5 and Comparative Examples 1 and 2, a printing test was performed with an offset sheet-fed printing press, and the dampening water supply dial (water dial) 10 was set to the standard state, and the water dial (1) Concentration change at the maximum amount of dampening water (concentration reduction rate), (2) Water evaluation at the time of maximum dampening water (water), (3) Humidity Evaluation of soil contamination (soil contamination) when the amount of water supplied was small. The dampening water supply amount is lower as the water dial is lower, and the larger the water supply amount, the higher the water supply amount.

(Printing conditions)
Printing machine: LITHRONE26 (manufactured by Komori Corporation)
Version: HP-F (manufactured by FUJIFILM Graphic Systems)
Dampening solution: AQUAUNITY C 2.0% aqueous solution (Toyo Ink Co., Ltd.)
Paper: Tokuhishi art double side N 127.9g / m2 Y (Mitsubishi Paper Co., Ltd.)
Speed: 12000sheet / hour
Print density: 1.60 (GretagMacbeth SpectroEye)
Color measurement conditions: density standard = DIN, white standard = blank paper, no filter (manufactured by X-rite)

(Density reduction rate evaluation)
The rate of decrease in concentration when the dampening water supply amount was maximum (water dial 30) was calculated from the following formula and evaluated according to the following evaluation criteria.
[a formula]
(Print density at 10 o'clock on the water dial-Print density at 30 o'clock on the water dial) ÷ (Print density at 10 o'clock on the water dial) x 100
[Evaluation criteria]
Concentration reduction rate of less than 5%: ○
Density reduction rate of 5% or more and less than 10%: Δ
Concentration reduction rate of 10% or more: ×
* The lower the rate of decrease, the better.

(Water evaluation)
[Evaluation criteria]
Cannot visually check the water: ◎
Slight water can be confirmed visually: ○
Water eyes can be clearly confirmed by visual inspection: ×
* Indicates that the water without water is better.

(Earth dirt evaluation)
[Evaluation criteria]
Water dial when dirt on non-image area occurs
4-5: ○
6-7: △
8-9: ×
* A smaller value means better.

  The results evaluated according to the above criteria are shown in Table 2.

  As shown in FIGS. 5A and 5B, Examples 1 to 5 have a high printing density stability even in a state where the dampening water is excessively increased, and the degree of water can be slightly confirmed. In addition, it was confirmed that even when the dampening water was squeezed, no soiling occurred and the water width was wide. On the other hand, in Comparative Examples 1 and 2, the change in concentration when the dampening water increased excessively was large, and water spots were also confirmed.

Claims (5)

In the method for producing a rosin-modified phenol resin (A) obtained by reacting a rosin (a) and a resol type phenol resin (b) and then reacting with a polyhydric alcohol (c), the following (1), (2) A process for producing a rosin-modified phenolic resin (A), characterized in that
(1) The polyhydric alcohol is allowed to react by being divided into two or more times.
(2) Polyhydric alcohol (c2) is 5 to 40% by weight based on the total charged amount of polyhydric alcohol (c).
However, the polyhydric alcohol reacted for the first time is polyhydric alcohol (c1),
The polyhydric alcohol that is reacted after the second time is referred to as polyhydric alcohol (c2). The method for producing a rosin-modified phenolic resin (A) according to claim 1, wherein when reacting the polyhydric alcohol (c2), the acid value of the rosin-modified phenolic resin intermediate (M) is 60 or less.
However, the rosin-modified phenol resin obtained by reacting the rosin (a) and the resole-type phenol resin (b) and then reacting with the polyhydric alcohol (c1) is referred to as a rosin-modified phenol resin intermediate (M).   A rosin-modified phenolic resin (A) produced by the production method according to claim 1 or 2.   A lithographic printing ink comprising the rosin-modified phenolic resin (A) according to claim 3.   A printed matter obtained by printing the lithographic printing ink according to claim 4 on a substrate.