JP6352737B2 - Offset printing ink and printed matter - Google Patents

Description

  The present invention relates to an offset printing ink, and more particularly to a osmotic drying offset printing ink in which a dry film is formed by osmotic drying.

Penetration drying type offset printing ink generally uses solvent, vegetable oil, pigment or resin contained in printing ink, and solvent or vegetable oil penetrates into the fiber part of paper by capillary action, while pigment, resin, etc. It takes a drying mechanism in which some solid matter is fixed on the paper surface and forms a film. Moreover, since the penetrating dry type offset printing ink is distinguished from a drying mechanism that forms a film by evaporating and drying the solvent in the ink by passing through a heating oven (dryer) called heat set printing ink, Also called cold set printing ink.
In the recent newspaper printing industry, which mainly uses penetrating dry offset printing inks, the speed of printing presses has been increasing in response to the improvement in productivity. As a result, printing inks are also required to be improved in high-speed printing suitability such as on-machine stability, suppression of misting, setability, and inking properties.

  In addition, the quality of printing paper has declined due to cost reductions, etc. When printing with conventional ink, if the ink has a high tackiness (tack), paper with low quality and low paper strength will be damaged. It becomes easy to do. Paper peeling means that the surface layer of the paper is torn off or peeled off by the adhesiveness (tack) of the ink. The tackiness (tack) of the ink is measured by the method described in JIS K5701-1. Examples of methods for preventing this paper peeling include lowering the tack of ink, improving fluidity, and improving on-machine stability. However, if the ink solvent is increased in order to simply lower the tack of the ink, the fluidity is improved, but the viscosity of the ink is lowered, so that an increase in misting and a reduction in on-machine stability occur. In particular, in the case of newspaper printers, the ink roller (rubber) in the printing press unit is often not passed through water, and in long run printing, heat is generated due to the friction of the metal roller in contact with the rubber roller. The solvent is easily volatilized, and the ink is easily fixed on the plate surface and the roller (also called piling). Ink solubility is important in order to suppress such ink sticking.

  In order to adjust the solubility of the ink, there are a method using a resin (highly soluble resin) highly compatible with the solvent used and a method using an ester solvent having a high dissolving power. However, the high-melting resin has a low molecular weight and the resin viscosity tends to be low, so it is excellent in roller cleaning after printing. And the set gets faster. In osmotic drying printing, it is useful to slow down these penetrations and delay the set. In particular, in recent years, demand for high-definition printing has also increased in newspaper printing. In this printing, the halftone dots are small and the ink film thickness is thin, so that setting is quicker and piling tends to occur. On the other hand, the use of an ester solvent is excellent in roller cleaning properties, but because of its high dissolving power, the fluidity increases, which causes increased misting and reduced on-machine stability.

On-machine stability refers to the stability of tackiness (tack) on a printing press during printing. For example, if the evaporation rate of the solvent component in the ink is high, the tackiness (tack) of the ink gradually increases and the paper tends to be peeled off. Therefore, such an ink is said to have poor on-machine stability. An ink with good on-machine stability can be said to be an ink with little fluctuation in tackiness (tack). As described above, low quality paper with low paper surface strength has been increasingly used, and ink with good on-machine stability is required.
For this reason, vegetable oil or machine oil having a relatively high viscosity is used in combination, but when vegetable oil or the like is increased, the drying property (setting property) is lowered. On the other hand, machine oil is a petroleum solvent composed of finite petroleum resources, and aromatic components contained therein are known as substances that adversely affect the human body. These are released from the printing process or from the ink coating of the printed matter, which causes environmental burdens such as the printing work environment and air pollution.

  In addition, as described above, increasing the ink solvent to lower the tack of the ink causes increased misting and decreased on-machine stability. For these measures, calcium carbonate, kaolin, silica, organic Although so-called extender pigments such as bentonite are also added, on the other hand, thixotropy becomes strong and fluidity may be remarkably lowered, and it is difficult to maintain appropriate fluidity.

  In particular, in the recent newspaper printing industry, automatic printing ink supply systems have become common due to increased productivity, faster printing presses and labor savings, and a large capacity installed in a separate ink chamber. Ink is temporarily supplied from the ink tank to a temporary supply tank, etc., and printing ink is supplied from there through a high-pressure pump to the ink supply section (ink rail, etc.) of the printing press unit. . In general, this system is equipped with a feed pipe that pumps ink from a temporary supply tank to the vicinity of the printing press unit at a high pressure. A valve is installed, and the pressure is reduced to a value suitable for the pump. Furthermore, when there are printing units that are not used or inks that are not used for printing because the printed image is small, etc., these need to be returned to the temporary supply tank. Thus, the ink is circulated between the temporary supply tank and the printing press unit via the feed pipe and the return pipe.

  Here, in such an automatic supply system, for example, when there is a time during which printing is not performed (for example, 8 to 10 hours) or maintenance of the printing press, the circulation of ink may be stopped. In this case, the flow of ink stops in the pipe. In such a state, a “margin” peculiar to ink occurs. Ink is a so-called non-Newtonian fluid. When the ink stops flowing, the apparent viscosity of the ink rises rapidly due to thixotropy or plasticity, and if it tries to flow again, it may not flow immediately. Ink supply to the machine unit becomes difficult, and printing troubles such as density reduction due to insufficient ink supply during reprinting occur. Even when the flow of ink stops, an ink that does not cause printing troubles due to insufficient fluidity, especially ink that has sufficient fluidity and suppresses "coldness" is required. is there.

Patent Document 1 discloses an offset ink composition containing a varnish obtained by dispersing and dissolving a resin for a varnish and a dissolution aid in an organic solvent, and the dissolution aid contains a polyhydric alcohol fatty acid ester other than vegetable oil. ing.
Patent Document 2 discloses a printing ink varnish containing a trihydric alcohol ester of tall oil fatty acid and a printing ink containing a pigment in a printing ink varnish.
Patent Document 3 discloses a lithographic printing ink composition containing tall oil fatty acid ester.
Patent Document 4 discloses an osmotic offset printing ink composition containing a gel fatty acid glyceride synthesized from fatty acid monoglyceride, diglyceride and aluminum 2-ethylhexylate.

  Patent Documents 1 to 4 all use esters, but Patent Document 1 uses a low-solubility resin and supplements with a polyhydric alcohol fatty acid ester as a solubilizing agent. It is a drying aid for increasing the release property. Specific examples include tricaproic acid glycerides and tri (caprylic / capric) glycerides, which are said to be effective in coating film curability. However, there are descriptions and suggestions for on-machine stability, fluidity and ink tightness. Absent. Patent Document 2 uses an ester to give a dryness comparable to that of soybean oil. Specific examples include tall oil fatty acid glycerin ester, trimethylolpropane ester and trimethylolethane. However, there is no description or suggestion about on-machine stability, fluidity and ink tightness. Patent Document 3 is an ester useful for compatibility with a resin in waterless ink, and only the normal butyl ester of tall oil fatty acid is described in the examples, and on-machine stability, fluidity and ink tightness are described. There is no suggestion. Patent Document 4 is an ink using a gelled ester solvent, which is effective for suppressing fluidity, but is different from the gist of the present invention, and is sufficient from the examples. Whether fluidity is ensured is unknown, and there is no description or suggestion about on-machine stability and ink tightness.

  In Patent Documents 5 to 7, lithographic printing produced by adding and mixing a dry pulverized product obtained by dry pulverizing crude copper phthalocyanine and a specific rosin resin, a printing ink solvent, a varnish for printing ink, an auxiliary agent for printing ink, etc. Ink is disclosed, animal and vegetable oils and fatty acid monoesters are suitable as printing ink solvents, fluidity and ink can be prevented by preventing redness and dispersibility deterioration due to copper phthalocyanine. Although it is evaluated for tightness, there are examples in which fluidity or inkness is inferior to the standard, and it is clear that it is not sufficient, and on-machine stability is described There is no suggestion.

JP 2009-73753 A JP 2010-285520 A JP 2012-201883 A JP 2013-213112 A JP 2008-270512 A JP 2009-155579 A JP 2009-155582 A

  Therefore, the present invention satisfies the basic performance as a printing ink, and is produced using an offset printing ink having good on-machine stability and fluidity and with reduced ink tightness, and the offset printing ink. It is an object to provide a printed matter.

  As a result of intensive studies, the present inventor has found that the above problem can be solved by containing a specific tall oil fatty acid ester in the offset printing ink, and has completed the present invention.

That is, the present invention
(1) An offset printing ink containing a rosin-modified phenolic resin, a tall oil fatty acid ester, a pigment, and a solvent,
Tall oil fatty acid ester, a tall oil fatty acid, and dimer acid, Ri esters der obtained by reacting a 3 and / or 4-valent alcohols,
An offset printing ink comprising 5 to 30% by weight of the dimer acid as a reaction component of the tall oil fatty acid ester ,
(2) The offset printing ink according to (1), wherein the tall oil fatty acid ester is 1 to 20% by weight in the printing ink,
(3) The hydroxyl value of the tall oil fatty acid ester is within the range of 20 to 80 mgKOH / g, the acid value is 4 mgKOH / g or less,
And a weight average molecular weight being in the range of 1,500～6,000 (1) or offset printing ink according to any one of (2),
(4) The difference of the shear viscosity η of the offset printing ink (η [20 minutes] −η [5 minutes]) is defined as the difference of the shear viscosity η of the offset printing ink not containing the tall oil fatty acid ester being 100. Sometimes the offset printing ink according to any one of (1) to ( 3 ), wherein the offset printing ink is 40 to 95,
(Here, the difference in shear viscosity η (η [20 minutes] −η [5 minutes]) is a strain of 10% for 5 minutes at 25 ° C. using a cone plate having a diameter of 25 mm and a cone angle of 1 °. The shear viscosity η (η [5 minutes]) when the structure of the ink was destroyed was measured under the conditions of a shear rate of 30 sec ⁻¹ , and subsequently, under the conditions of a strain of 10% and a shear rate of 5 sec ⁻¹ . The value obtained by subtracting the 5-minute shear viscosity η (η [5 minutes]) from the 20-minute shear viscosity η (η [20 minutes]) when the shear viscosity η was measured for 15 minutes)
(5) Printed matter obtained by printing the offset printing ink according to any one of (1) to ( 4 ) on paper as a base material,
It is.

ADVANTAGE OF THE INVENTION According to this invention, after satisfy | filling the basic performance as printing ink, the printed matter produced using the offset printing ink with favorable on-machine stability and fluidity | liquidity and the said offset printing ink can be provided.
In particular, as an osmotic drying type offset printing ink for newspapers, books, flyers, etc., it has excellent characteristics that it can be used without reducing the productivity during printing, with improved on-machine stability and fluidity. .

  Hereinafter, embodiments for carrying out the present invention will be described in detail. Note that this embodiment is merely an embodiment for carrying out the present invention, and the present invention is not limited by this embodiment, and various modified embodiments can be made without departing from the gist of the present invention. Is possible.

  The offset printing ink of the present invention is produced by kneading and containing a rosin-modified phenolic resin, tall oil fatty acid ester, pigment, solvent, etc., and the tall oil fatty acid ester comprises tall oil fatty acid, dimer acid, 3 and It is preferably an ester obtained by reacting with a tetrahydric alcohol.

  It is obtained by subjecting tall oil fatty acid, dimer acid and tri- and / or tetrahydric alcohol to a dehydration reaction by a conventionally known method. Moreover, a publicly known and used esterification catalyst can also be used as needed. Examples of the esterification catalyst include known Lewis acids such as tetraisopropoxytitanium or Lewis base. After the reaction, the triester may be purified by vacuum distillation or the like, or the triester alone may be isolated by treatment such as molecular distillation or adsorption.

  The acid value of tall oil fatty acid ester is preferably 4 mgKOH / g or less. Moreover, it is preferable that the hydroxyl value of tall oil fatty acid ester exists in the range of 20-80 mgKOH / g. Furthermore, it is preferable that the weight average molecular weight of tall oil fatty acid ester is in the range of 1,500 to 6,000. When the acid value, the hydroxyl value, and the weight average molecular weight are within the above ranges, a printing ink excellent in balance between on-machine stability and fluidity can be obtained.

  The tall oil fatty acid used in the present invention is obtained by rectification of crude tall oil, which is a by-product in the kraft pulp process, and the main fatty acids are oleic acid and linoleic acid, and contains a small amount of conjugated linoleic acid. Is done. Examples of commercially available products include Hartle FA-1, Hartle FA-1P, and Hartle FA-3S (manufactured by Harima Kasei Co., Ltd.).

  The dimer acid used in the present invention is preferably tall oil fatty acid having an iodine value of 120 to 145, soybean oil fatty acid, cottonseed oil fatty acid, rice bran oil fatty acid, etc., especially tall oil fatty acid and rice bran oil fatty acid having a relatively high oleic acid content. Is more preferable. As a commercial product, it can be obtained as the Haridimer series (manufactured by Harima Kasei Co., Ltd.) A dimerized tall oil fatty acid as a commercial product may be used. However, the structure of this dimer acid is not single, and may be a mixture of acyclic, monocyclic and polycyclic. In addition, commercially available dimer acids may also contain a small amount of monomeric acid, trimer acid and the like.

  Examples of the tri- and / or tetrahydric alcohol used in the present invention include glycerin, propane-1,1,3-triol, 1,2,3-butanetriol, 1,2,4-butanetriol, 1,1,4. -Butanetriol, 2- (hydroxymethyl) -1,3-propanediol, 2-methylpropane-1,1,1-triol, 2-methyl-1,2,3-propanetriol, trimethylolethane, 2, 3,4-pentanetriol, 1,2,3-pentanetriol, 1,2,4-pentanetriol, 1,2,5-pentanetriol, 1,3,4-pentanetriol, 1,3,5-pentane Triol, 2-methyl-1,2,4-butanetriol, 3-methyl-1,2,3-butanetriol, 2-methylbutane-1,2,3-trio 2-ethylbutane-1,2,3-triol, 2- (hydroxymethyl) -1,3-butanediol, 2- (hydroxymethyl) -1,4-butanediol, 2-ethyl-1,2, 3-propanetriol, trimethylolpropane, 2,4-dihydroxy-3-hydroxymethylpentane, 2-hydroxymethyl-3-methylbutane-1,3-diol, 2-methylpentane-1,3,5-triol, 3, -Methylpentane-1,3,5-triol, 2-methylpentane-1,2,3-triol, 3-methylpentane-1,2,5-triol, 1,2,3-hexanetriol, hexane-1 , 2,4-triol, 1,2,5-hexanetriol, 1,2,6-hexanetriol, 1,3,5-hexanetriol, 4,5-hexanetriol, hexane-1,3,6-triol, hexane-2,3,4-triol, 2,2-di (hydroxymethyl) -3-butanol, 3-hydroxymethyl-1,5- Trivalent alcohols such as pentanediol, 3,3-dimethyl-1,2,4-butanetriol, 2-isopropylpropane-1,2,3-triol, 1,2,3,4-butanetetraol, 1, 1,4,4-butanetetraol, pentaerythritol, 1,1,5,5-pentanetetraol, 1,2,3,5-pentanetetraol, 1,2,4,5-pentanetetraol, 2 -Methyl-1,2,3,4-butanetetraol, 1,2,4,5-hexanetetraol, 1,2,5,6-hexanetetraol, 2,2-bis (hydroxy Methyl) -1,4-butanediol, 4-methylpentane-1,2,4,5-tetraol and other tetrahydric alcohols such as linear or branched polyhydric alcohols having 3 to 6 carbon atoms Is mentioned. Of these, glycerin, trimethylolpropane, pentaerythritol, and trimethylolethane are more preferable.

  The tall oil fatty acid ester is an ester obtained by reacting tall oil fatty acid, dimer acid, 3 and / or tetrahydric alcohol, and the dimer acid is one of them when the total amount of these reaction components is 100% by weight. It is preferable to contain 5 to 30% by weight. Of these, 10 to 20% by weight is particularly preferable. If the dimer acid is less than 5% by weight, the weight average molecular weight becomes low, the fluidity becomes excessive, and the solubility becomes high, so that the cohesive force of the ink is lowered, and the stain and misting are liable to increase. If the dimer acid exceeds 30% by weight, the weight average molecular weight increases, the fluidity decreases, and it becomes difficult to have good thixotropic properties. And ink ink-applying property on the paper surface are likely to decrease. By being in the said range, the printing ink which is excellent in balance with on-machine stability and fluidity | liquidity is obtained. Moreover, since the dissolving power is maintained, the printing ink which is excellent in roller washability is obtained.

  The acid value of the tall oil fatty acid ester of the present invention is preferably 4 mgKOH / g or less. Among these, 2 mgKOH / g or less is more preferable, and 1-2 mgKOH / g is particularly preferable. When the acid value is larger than 4 mgKOH / g, the polarity becomes high, so that emulsification is facilitated, and the occurrence of soiling and the reduction in halftone dot reproducibility due to the decrease in cohesive force occur. The acid value is a value measured according to JIS K5601.

  The hydroxyl value of the tall oil fatty acid ester of the present invention is preferably 20 to 80 mgKOH / g. Of these, 30 to 70 mg KOH / g is particularly preferable. When the hydroxyl value is less than 20 mgKOH / g, the cohesive force is lowered when the ink is emulsified, and the fluidity becomes excessive, so that it becomes dirty and the dot reproducibility is lowered. If it exceeds 80 mgKOH / g, the emulsification rate increases and the cohesive strength of the emulsified ink also increases, so that the fluidity is insufficient. If the fluidity is lowered due to excessive emulsification, the ink tends to be excessive on the roller, causing stains, misting, color loss and density fluctuation. The hydroxyl value is the number of mg of potassium hydroxide required to acetylate the OH group contained in 1 g of the sample. It is obtained by acetylating OH groups in a sample with acetic anhydride and titrating the produced acetic acid with a potassium hydroxide solution.

  The tall oil fatty acid ester of the present invention preferably has a weight average molecular weight of 1,500 to 6,000. Of these, 2,000 to 4,000 is particularly preferable. When the weight average molecular weight is less than 1,500, the viscosity and yield value (cohesive force) of the printing ink are lowered, and the fluidity becomes excessive. Moreover, if the viscosity of the ink is too low, it will be easy to see through. If it exceeds 6,000, the ink has a high viscosity, the cohesive force becomes too high, the fluidity is insufficient, and the permeation drying property is slow. Here, the weight average molecular weight is a value measured by the GPC method (polystyrene conversion).

  As described above, in long-run printing, heat is generated by friction between the ink roller made of rubber in the printing press unit and the metal roller, and the solvent in the ink is likely to volatilize. However, the tall oil fatty acid ester of the present invention has the acid value, the hydroxyl value, and the weight average molecular weight within the above ranges, respectively, so that the solubility in a resin having a high viscosity and a high crosslinking density can be reduced. Therefore, the resin can remain on the paper surface even in areas where the halftone dot is small, such as in high-definition printing, which slows down the set-up and suppresses piling and the increase in tack over time. (Because it has good stability) and has an appropriate viscosity, the tackiness of the ink can be kept low and the fluidity must not be excessive. . In addition, there is an effect that moderate fluidity that does not cause excessive fluidity can be imparted, and ink jamming can be suppressed.

  The tall oil fatty acid ester of the present invention is preferably 1 to 20% by weight in the printing ink. Especially, 5 to 15 weight% is especially preferable. When the amount is less than 1% by weight, solvent detachment on the printing press cannot be suppressed, and the increase in tack over time cannot be suppressed, so that wicking due to paper peeling or ink sticking to the roller tends to occur. If it exceeds 20% by weight, solvent detachment on the printing press will be suppressed, and tack rise over time will be suppressed, but penetrability will be slow, and ink will be taken off to the guide roller and set-off will likely occur. Become.

  The offset printing ink of the present invention contains a printing ink varnish (hereinafter also simply referred to as varnish), tall oil fatty acid ester, pigment, solvent and the like.

  The varnish for printing ink may be produced by a conventionally known method, and is produced by heating and mixing a rosin-modified phenol resin, a solvent, a chelating agent and the like.

As the rosin-modified phenolic resin, those conventionally used in offset printing inks can be used. The rosin-modified phenolic resin preferably has a weight average molecular weight in the range of 40,000 to 300,000. Among these, particularly preferred is a weight average molecular weight in the range of 90,000 to 170,000. When the weight average molecular weight exceeds 300,000, the solubility decreases, and the solvent releasability becomes faster, so that the on-machine stability is inferior and paper peeling tends to occur. Moreover, since it has high elasticity, it tends to cause a decrease in pigment dispersibility, a decrease in thickness on the paper surface, and a decrease in gloss due to a decrease in leveling and fluidity.
Here, the weight average molecular weight is a value measured by the GPC method (polystyrene conversion).

  The content of the rosin-modified phenol resin is preferably in the range of 20 to 35% by weight in the total amount of offset printing ink. If it is less than 20% by weight, since the solid content is small, the viscosity becomes low, the fluidity becomes excessive and it becomes difficult to obtain a desired ink, and if it exceeds 35% by weight, the gloss tends to be lowered.

  As the solvent used in the present invention, for the purpose of imparting fluidity, an AF solvent, a normal paraffin solvent, an isoparaffin solvent, a petroleum solvent typified by a machine oil, a cylinder oil, a vegetable oil, a vinylidene olefin, etc. It can be appropriately selected and used.

  As the vegetable oil used in the present invention, soybean oil or a fatty acid ester derived from soybean oil is mainly used. Examples of other vegetable oils include linseed oil, rapeseed oil, coconut oil, olive oil, tung oil, and the like, and those obtained by regenerating them. Other fatty acid esters derived from vegetable oils include, for example, fatty acids derived from dry oil or semi-dry oil such as cottonseed oil, linseed oil, safflower oil, sunflower oil, tung oil, tall oil, dehydrated castor oil, rapeseed oil, sesame oil, etc. A monoalkyl ester can be illustrated. The alcohol-derived alkyl group constituting the fatty acid monoalkyl ester preferably has 1 to 12 carbon atoms, and specific examples include methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl. , Dodecyl, 3-methyl-1-butyl, 2,2-bis (hydroxymethyl) butyl, 2,4-dimethyl-3-pentyl, 2-ethyl-1-butyl, 2-ethyl-1-hexyl, 3, 5,5-trimethyl-1-hexyl, 4-decyl, 2-isopropyl-5-methyl-1-hexyl, 2-butyl-1-octyl and the like. Of these, methyl, ethyl, propyl, butyl, isobutyl, octyl, 2-ethylhexyl, 2,2-bis (hydroxymethyl) butyl and the like are particularly preferable. The vegetable oils have an excellent effect of improving the gloss of printed matter because of increased solubility in resins. However, if the tall oil fatty acid ester of the present invention is used, it is preferable not to use a fatty acid ester derived from soybean oil or a fatty acid ester derived from other vegetable oils.

  The vegetable oil (including the tall oil fatty acid ester of the present invention) is preferably in the range of 30 to 50% by weight based on the total amount of the offset printing ink of the present invention. Among these, particularly preferable is the range of 35 to 45% by weight. If it is less than 30% by weight, the gloss is lowered. Even if an amount exceeding 50% by weight is added, the effect of improving the gloss is not obtained, the solubility is increased, the piling is easy, and the increase of the tack over time is increased. Adhesiveness increases, aftertack remains, and it becomes easy to peel off the paper.

  The ratio of the soybean oil to the tall oil fatty acid ester of the present invention (if the fatty acid ester derived from soybean oil or other vegetable oil-derived fatty acid ester is included, the total amount of fatty acid esters including them) is 100/0 by weight. It is preferable to be within the range of -30/70. Especially, it is especially within the range of 90 / 10-50 / 50. When the tall oil fatty acid ester of the present invention exceeds 70% by weight in the ratio of soybean oil to the tall oil fatty acid ester of the present invention, the tack becomes high and the paper is easily peeled off.

  The chelating agent used in the present invention functions as a gelling agent, but metal chelates, particularly aluminum chelate compounds such as ethyl acetoacetate aluminum diisopropoxide and aluminum trisethyl acetoacetate are preferably used.

  The pigment used in the present invention is an organic pigment or an inorganic pigment, such as an organic pigment typified by disazo yellow, carmine 6B, phthalocyanine blue, etc., and an inorganic pigment typified by carbon black, calcium carbonate, etc. There is no particular limitation.

  Since many of the organic pigments are often synthesized in water, they are processed and used in a paste form that is squeezed to a certain degree of moisture, and kneaded with varnish, kneader, extruder, continuous kneader, etc. Kneaded with a machine and used for offset printing ink. More specifically, the organic pigment paste and the varnish are kneaded with a kneader, the organic pigment is transferred to the varnish, water is separated and removed, and then the remaining water is removed by reducing the pressure (referred to as a flushing method). A mixture of pigment and varnish.

  In the present invention, other additives such as a pigment dispersant, an emulsifier, a drying inhibitor, a drying accelerator, a surface conditioner, and a lubricant can be appropriately used for the purpose of improving the function as an ink.

  For example, as anti-friction, anti-blocking agent and slip agent, natural wax such as carnauba wax, paraffin wax, microcrystalline wax, Fischer Trops wax, polyethylene wax, polypropylene wax, polytetrafluoroethylene wax, polyamide wax, silicone Synthetic waxes such as compounds can be exemplified.

  The printed matter of the present invention can be produced by ordinary offset printing on paper as a base material.

  As the base material used in the printed matter of the present invention, any paper that can be used for normal offset printing can be used, and in particular, an additional paper suitable for offset printing (non-coated paper), fine coated paper, coated paper, art paper Paper or the like is preferably used.

The offset printing ink of the present invention has its shear viscosity when the difference in shear viscosity η (η [20 minutes] −η [5 minutes]) of the offset printing ink not containing the tall oil fatty acid ester of the present invention is 100. The ratio of η difference is preferably 40 to 95. Especially, 60-85 are especially preferable. The difference in shear viscosity η of ink (η [20 minutes] −η [5 minutes]) was measured using a viscoelasticity measuring device such as a Physica MCR301 viscoelasticity measuring device (manufactured by Anton Paar) with a diameter of 25 mm and a cone angle of 1 The shear viscosity η (η [5 minutes]) when the structure of the ink was destroyed under the conditions of a strain cone of 10% and a shear rate of 30 sec ⁻¹ for 5 minutes at 25 ° C. using a ° cone plate. Measured, and then the shear viscosity η (η [20 minutes]) of 20 minutes when the shear viscosity η was measured for 15 minutes under the conditions of 10% strain and 5 sec ⁻¹ shear rate, the 5 minute shear. It can be determined by subtracting the viscosity η (η [5 minutes]). The smaller this difference is, the smaller the ink viscosity fluctuation becomes, and the more difficult the ink is to be stuck.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. In the examples, “part” indicates “part by weight” and “%” indicates “% by weight”.

[Adjustment of offset printing ink varnish]
Production Example 1
Rosin-modified phenol resin R1 (weight average molecular weight 126,000, 33% O solvent tolerance 3.1, acid value 19.1 mgKOH / g, hydroxyl value 63 mgKOH / g, Arakawa Chemical Industries, Ltd.) 17 parts, rosin-modified phenol Resin R2 (weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mgKOH / g, hydroxyl value 120 mgKOH / g, manufactured by Arakawa Chemical Co., Ltd.) 15 parts, soybean white tightening oil 38 parts, AF 11 parts of Solvent 6 (manufactured by JX Nippon Oil & Energy Corporation), 131120A (tall oil fatty acid glycerin ester (dimer acid 15%), weight average molecular weight 2,500, acid value 1.1, hydroxyl value 35, Harima Chemical ( Co., Ltd.) and 18 parts of an aluminum chelating agent (8% octope aluminum, manufactured by Hope Pharmaceutical Co., Ltd.) in a reaction vessel. While blowing gas temperature was raised to 185 ° C., and stirred and mixed for 60 minutes to obtain a varnish V1. The varnish had a heptane tolerance of 505% and an alcohol number of 25.7 ml.

Production Example 2
Rosin-modified phenolic resin R3 (weight average molecular weight 200,000, 5 solvent tolerance 1.0, acid value 18 mgKOH / g, hydroxyl value 47.6 mgKOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 16 parts, rosin-modified phenolic resin R2 (Weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mgKOH / g, hydroxyl value 120 mgKOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 16 parts, soybean white oil 35 parts, AF solvent 6 12 parts (manufactured by JX Nippon Oil & Energy Corporation), 131120A (tall oil fatty acid glycerin ester (15% dimer acid), weight average molecular weight 2,500, acid value 1.1, hydroxyl value 35, Harima Kasei Co., Ltd. 20 parts) and 1 part of an aluminum chelating agent (ALCH, manufactured by Kawaken Fine Chemical Co., Ltd.) are charged into a reaction vessel, and nitrogen gas is supplied. The temperature was raised to narrowing while 185 ° C. can, and stirred and mixed for 60 minutes to obtain a varnish V2. The varnish had a heptane tolerance of 324% and an alcohol number of 30.1 ml.

Production Example 3
Rosin-modified phenol resin R1 (weight average molecular weight 126,000, 33% O solvent tolerance 3.1, acid value 19.1 mgKOH / g, hydroxyl value 63 mgKOH / g, Arakawa Chemical Industries, Ltd.) 17 parts, rosin-modified phenol Resin R2 (weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mg KOH / g, hydroxyl value 120 mg KOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 15 parts, soy white squeezed oil 38 parts, AF Solvent 6 (manufactured by JX Nippon Oil & Energy Co., Ltd.) 11 parts, 130324A (tall oil fatty acid glycerin ester (dimer acid 30%), weight average molecular weight 5,300, acid value 1.8, hydroxyl value 30, Harima Chemical ( Co., Ltd.) and 18 parts of an aluminum chelating agent (8% octope aluminum, manufactured by Hope Pharmaceutical Co., Ltd.) in a reaction vessel. While blowing gas temperature was raised to 185 ° C., and stirred and mixed for 60 minutes to obtain a varnish V3. The varnish had a heptane tolerance of 461% and an alcohol number of 26.3 ml.

Production Example 4
Rosin-modified phenol resin R1 (weight average molecular weight 126,000, 33% O solvent tolerance 3.1, acid value 19.1 mgKOH / g, hydroxyl value 63 mgKOH / g, Arakawa Chemical Industries, Ltd.) 17 parts, rosin-modified phenol Resin R2 (weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mg KOH / g, hydroxyl value 120 mg KOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 15 parts, soy white squeezed oil 38 parts, AF 11 parts of Solvent 6 (manufactured by JX Nippon Oil & Energy Corporation), 130324D (tall oil fatty acid pentaerythritol ester (15% dimer acid), weight average molecular weight 3,500, acid value 2, hydroxyl value 30, Harima Kasei Co., Ltd. )) 18 parts, and 1 part of aluminum chelating agent (8% Octopu Aluminum, manufactured by Hope Pharmaceutical Co., Ltd.) in a reaction vessel , While blowing nitrogen gas heated to 185 ° C., and stirred and mixed for 60 minutes to obtain a varnish V4. The varnish had a heptane tolerance of 500% and an alcohol number of 25.6 ml.

Production Example 5
Rosin-modified phenol resin R1 (weight average molecular weight 126,000, 33% O solvent tolerance 3.1, acid value 19.1 mgKOH / g, hydroxyl value 63 mgKOH / g, Arakawa Chemical Industries, Ltd.) 17 parts, rosin-modified phenol Resin R2 (weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mg KOH / g, hydroxyl value 120 mg KOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 15 parts, soy white squeezed oil 38 parts, AF 11 parts of Solvent 6 (manufactured by JX Nippon Oil & Energy Corporation), 130324C (tall oil fatty acid glycerin ester (dimer acid 15%), weight average molecular weight 2,000, acid value 1.6, hydroxyl value 70, Harima Kasei ( Co., Ltd.) and 18 parts of an aluminum chelating agent (8% octope aluminum, manufactured by Hope Pharmaceutical Co., Ltd.) in a reaction vessel. While blowing gas temperature was raised to 185 ° C., and stirred and mixed for 60 minutes to obtain a varnish V5. The varnish had a heptane tolerance of 443% and an alcohol number of 27.4 ml.

Production Example 6
Rosin-modified phenol resin R1 (weight average molecular weight 126,000, 33% O solvent tolerance 3.1, acid value 19.1 mgKOH / g, hydroxyl value 63 mgKOH / g, Arakawa Chemical Industries, Ltd.) 17 parts, rosin-modified phenol Resin R2 (weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mg KOH / g, hydroxyl value 120 mg KOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 15 parts, soy white squeezed oil 38 parts, AF Solvent 6 (manufactured by JX Nippon Oil & Energy Co., Ltd.) 11 parts, 130324B (tall oil fatty acid glycerin ester (dimer acid 5%), weight average molecular weight 1,800, acid value 1.4, hydroxyl value 30, and Harima Kasei ( 18 parts) and 1 part of an aluminum chelating agent (8% octope aluminum, manufactured by Hope Pharmaceutical Co., Ltd.) in a reaction vessel, and nitrogen While blowing scan was raised to 185 ° C., and stirred and mixed for 60 minutes to obtain a varnish V6. The varnish had a heptane tolerance of 450% and an alcohol number of 27.2 ml.

Production Example 7
Rosin-modified phenol resin R1 (weight average molecular weight 126,000, 33% O solvent tolerance 3.1, acid value 19.1 mgKOH / g, hydroxyl value 63 mgKOH / g, Arakawa Chemical Industries, Ltd.) 17 parts, rosin-modified phenol Resin R2 (weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mg KOH / g, hydroxyl value 120 mg KOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 15 parts, soy white squeezed oil 38 parts, AF Solvent 6 (manufactured by JX Nippon Oil & Energy Corporation) 11 parts, 130702A (Tall oil fatty acid glycerin ester (dimer acid 0%), weight average molecular weight 1,000, acid value 1.1, hydroxyl value 34.3, Harima 18 parts of Kasei Chemical Co., Ltd.) and 1 part of an aluminum chelating agent (8% Octopu Aluminum, manufactured by Hope Pharmaceutical Co., Ltd.) are charged into a reaction vessel. The temperature was raised to 185 ° C. while blowing hydrogen gas, mixed with stirring for 60 minutes, to obtain a varnish V7. The varnish had a heptane tolerance of 470% and an alcohol number of 26.5 ml.

Production Example 8
Rosin-modified phenol resin R1 (weight average molecular weight 126,000, 33% O solvent tolerance 3.1, acid value 19.1 mg KOH / g, hydroxyl value 63 mg KOH / g, Arakawa Chemical Industries, Ltd.) 20 parts, rosin-modified phenol Resin R2 (weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mg KOH / g, hydroxyl value 120 mg KOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 15 parts, soy white squeezed oil 38 parts, AF 29 parts of Solvent 6 (manufactured by JX Nippon Oil & Energy Co., Ltd.) and 1 part of an aluminum chelating agent (8% octope aluminum, manufactured by Hope Pharmaceutical Co., Ltd.) are charged into a reaction vessel and 185 ° C. while blowing nitrogen gas. The mixture was stirred and mixed for 60 minutes to obtain varnish V8. The varnish had a heptane tolerance of 365% and an alcohol number of 24.6 ml.

Production Example 9
Rosin-modified phenolic resin R3 (weight average molecular weight 200,000, 5 solvent tolerance 1.0, acid value 18 mgKOH / g, hydroxyl value 47.6 mgKOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 16 parts, rosin-modified phenolic resin R2 (Weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mgKOH / g, hydroxyl value 120 mgKOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 16 parts, soybean white oil 35 parts, AF solvent 6 12 parts (manufactured by JX Nippon Oil & Energy Corporation), 130702A (Tall oil fatty acid glycerin ester (dimer acid 0%), weight average molecular weight 1,000, acid value 1.1, hydroxyl value 34.3, Harima Kasei ( 20 parts) and 1 part of an aluminum chelating agent (ALCH, manufactured by Kawaken Fine Chemical Co., Ltd.) are charged into a reaction vessel and nitrogen gas is blown. The temperature was raised to 185 ° C. while Inclusive, and stirred and mixed for 60 minutes to obtain a varnish V9. The varnish had a heptane tolerance of 244% and an alcohol number of 29.3 ml.

Production Example 10
Rosin-modified phenolic resin R3 (weight average molecular weight 200,000, 5 solvent tolerance 1.0, acid value 18 mgKOH / g, hydroxyl value 47.6 mgKOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 16 parts, rosin-modified phenolic resin R2 (Weight average molecular weight 88,000, 5 solvent tolerance 1.3, acid value 26.7 mgKOH / g, hydroxyl value 120 mgKOH / g, manufactured by Arakawa Chemical Industries, Ltd.) 16 parts, soybean white oil 35 parts, AF solvent 6 32 parts (manufactured by JX Nippon Oil & Energy Corporation) and 1 part of an aluminum chelating agent (ALCH, manufactured by Kawaken Fine Chemical Co., Ltd.) were charged into a reaction vessel, and the temperature was raised to 185 ° C. while blowing nitrogen gas, The mixture was stirred and mixed for 60 minutes to obtain varnish V10. The varnish had a heptane tolerance of 270% and an alcohol number of 29.8 ml.

As for heptane tolerance, 5 g of varnish was weighed in a 100 ml beaker, dissolved in 45 g of toluene, and n-heptane was added dropwise with stirring at 20 ° C., the solution became cloudy and the newspaper type (10 points under the beaker) ) Is a numerical value calculated by the following equation from the n-heptane dripping amount (g) until it cannot be determined.
Heptane tolerance (%) = 100 × (n-heptane dripping amount g) / (varnish amount g)
Heptane tolerance is an index of the affinity of the solvent for the resin in the varnish. If it is greater than 600%, the stability on the printing press will be good, but when printing, the removal of the solvent will worsen and the set will be slow (dried). Difficult). On the other hand, if it is less than 400%, the ink state on the printing press becomes unstable, the fluidity is lowered, the transferability between rollers, and the fleshing on the paper surface are reduced, so that a high-quality printed matter can be stably produced. Disappear.

The alcohol number was determined by weighing 5 g of varnish in a 100 ml beaker, dissolving in 45 g of toluene, and dropping methanol with stirring at 20 ° C., and the solution became cloudy and the newspaper type (10 points) under the beaker could be judged. This is the amount of methanol dripped until it disappears (ml).
The alcohol number is an index that indirectly represents the ratio of hydroxyl groups in the varnish, and when it is larger than 32 ml, water tends to be taken in, so that it becomes easy to overemulsify, and ink entanglement and stains on the metering roller are likely to occur. On the other hand, if it is smaller than 25 ml, it becomes difficult to take in water, so that emulsification is difficult, the roller is easy to peel off, and ink transferability is impaired.

[Preparation of offset printing ink]
Examples 1-7 and Comparative Examples 1-5
Varnish, indigo pigment (Fastgen Blue GBK-19SD, manufactured by DIC Corporation), calcium carbonate (Neolite SA-300, manufactured by Takehara Chemical Industry Co., Ltd.) and AF Solvent 6 (JX Nippon Oil & Energy Corporation) Co., Ltd.), kneaded with a three-roll mill to obtain an ink base, and added with white soybean oil and AF solvent 6 (manufactured by JX Nippon Oil & Energy Corporation), mixed, and mixed with a viscosity of 7-8 Pa -The offset printing ink of Examples 1-7 of s and Comparative Examples 1-5 was obtained.

  The following table test was performed for the offset printing inks in Table 1. The results are shown in Table 2.

[Liquidity]
Each offset printing ink of Examples 1 to 7 and Comparative Examples 1 to 5 is weighed into an ink pipette and dropped on a reference line of a horizontally placed glass plate fluometer, and the glass plate is immediately set up vertically. The length that the printing ink flowed after 10 minutes was measured and evaluated after standing upright. The larger the measured value, the better the fluidity. Regarding the degree of fluidity, ◎: 130 mm or more and less than 135 mm, ○: 120 mm or more and less than 130 mm, Δ: 110 mm or more and less than 120 mm, or 135 mm or more and less than 140 mm (practical problem), x: less than 110 mm or 140 mm or more. It was evaluated with.

[Onboard stability]
Each offset printing ink of Examples 1-7 and Comparative Examples 1-5 was used an incometer (manufactured by Toyo Seiki Seisakusho Co., Ltd.), ink amount 1.31 cc, room temperature 25 ° C., roller temperature 30 ° C., rotation speed 1200 rpm The difference between the tack value at 0 minutes and the tack value after 10 minutes (tack change) was measured and evaluated. The smaller the tack change, the better the on-machine stability.
About tack change, ○: less than 0.5 (best on-machine stability), Δ: 0.5 to less than 1.0 (good on-machine stability, no problem in practical use), x: 1.0 or more (on-machine The stability was inferior).

[Margin of ink]
Each offset printing ink of Examples 1 to 7 and Comparative Examples 1 to 5 was measured at 25 ° C. using a cone plate having a diameter of 25 mm and a cone angle of 1 ° using a Physica MCR301 viscoelasticity measuring device (manufactured by Anton Paar). The shear viscosity η (η [5 minutes]) when the ink structure was broken was measured under the conditions of 5 minutes, strain 10%, shear rate 30 sec ⁻¹ , and then strain 10%, shear rate 5 sec. Subtract the 5-minute shear viscosity η (η [5 minutes]) from the 20-minute shear viscosity η (η [20 minutes]) when the shear viscosity η is measured for 15 minutes under the condition of ^-1. As the difference is smaller, the ink viscosity fluctuation is smaller and the ink is less likely to be stuck. In addition, it showed in the ratio when the difference of the shear viscosity (eta) of the offset printing ink which does not contain the tall oil fatty acid ester of this invention is set to 100. Examples 1 to 5 and Comparative Example 1 are ratios when Comparative Example 2 is used, Examples 6 and 3 are Comparative Example 4 and Example 7 is a ratio when Comparative Example 5 is 100.

[tack]
Each offset printing ink of Examples 1-7 and Comparative Examples 1-5 was used an incometer (manufactured by Toyo Seiki Seisakusho Co., Ltd.), ink amount 1.31 cc, room temperature 25 ° C., roller temperature 30 ° C., rotation speed 400 rpm. The numerical value (tack value) after 1 minute was measured under these conditions. The lower the tack value, the harder the paper will peel off.
The tack values were evaluated with ○: less than 3.0 and x: 3.0 or more.

[Emulsification test]
For each of the offset printing inks of Examples 1 to 7 and Comparative Examples 1 to 5, a lithotronic emulsification tester (manufactured by NOVOCONTROL) was used, and 25 g of ink was rotated at 1200 rpm at 40 ° C. and 2 ml / 25 g of ink. Water was added at a rate of minutes, and the amount of water at the time when the ink was saturated was measured and evaluated as the weight percent with respect to 25 g of ink.
Emulsification rate (%) = 100 × (moisture content g at saturation) / (ink content g)
It has been confirmed that the emulsification rate is preferably in the range of approximately 30 to 50% in a printing test using a printing press.

  From Table 2, Examples 1 to 7 have low tack, good fluidity, suppressed ink tightness, and excellent on-machine stability. That is, since all of the offset printing inks of Examples 1 to 7 are effective in suppressing paper peeling and have been provided with on-machine stability, the occurrence of ink piling can be suppressed, and further, the reduction in tack can be suppressed. While adding extender pigments, fluidity is improved, thixotropy is suppressed, and ink tightness is suppressed, so fluidity in the piping is not reduced, avoiding problems during printing It can be used without reducing productivity. Furthermore, since the dissolving power is maintained, the roller cleaning property is excellent and the workability is improved.

Claims (5)

An offset printing ink containing rosin-modified phenolic resin, tall oil fatty acid ester, pigment, and solvent,
Tall oil fatty acid ester, a tall oil fatty acid, and dimer acid, Ri esters der obtained by reacting a 3 and / or 4-valent alcohols,
An offset printing ink comprising 5 to 30% by weight of the dimer acid as a reactive component of the tall oil fatty acid ester . The offset printing ink according to claim 1, wherein the tall oil fatty acid ester is 1 to 20% by weight in the printing ink. The hydroxyl value of the tall oil fatty acid ester is within the range of 20 to 80 mgKOH / g,
The acid value is 4 mgKOH / g or less,
And, offset printing ink according to claim 1 or 2, wherein the weight average molecular weight in the range of 1,500～6,000. When the ratio of the shear viscosity η of the offset printing ink (η [20 minutes] −η [5 minutes]) is 100, the difference in shear viscosity η of the offset printing ink not containing the tall oil fatty acid ester is 100 It is 40-95, The offset printing ink in any one of Claims 1-3 characterized by the above-mentioned.
(Here, the difference in shear viscosity η (η [20 minutes] −η [5 minutes]) is a strain of 10% for 5 minutes at 25 ° C. using a cone plate having a diameter of 25 mm and a cone angle of 1 °. The shear viscosity η (η [5 minutes]) when the structure of the ink was destroyed was measured under the conditions of a shear rate of 30 sec ⁻¹ , and subsequently, under the conditions of a strain of 10% and a shear rate of 5 sec ⁻¹ . The value obtained by subtracting the 5-minute shear viscosity η (η [5 minutes]) from the 20-minute shear viscosity η (η [20 minutes]) when the shear viscosity η was measured for 15 minutes) The printed matter obtained by printing the offset printing ink in any one of Claims 1-4 on the paper which is a base material.