JP6532842B2 - Printing ink composition - Google Patents

Description

  The present invention relates to a printing ink composition, and more particularly to a printing ink composition suitable for a cold-drying offset sheet-fed lithographic printing ink and a heat-drying offset rotary printing lithographic ink.

  In general, the printing surface of a printed matter printed with offset lithographic printing ink is rubbed immediately after printing by contacting with a guide roll, a turn bar, a triangular plate or the back surface of another printed matter. In addition, the printing surface causes a so-called blocking phenomenon in which the composition of the printed ink is fused to the surface of the contact, causing a problem that the printing surface is significantly deteriorated and the surface of the contact is contaminated.

  In order to solve such problems, fine particles made of solid polymer such as resin and wax are added to the printing ink to form microprotrusions that impart lubricity to the printing surface after printing to form a printing surface It has been attempted to improve the wear resistance of the steel.

  Usually, since the thickness of the printing ink is about 0.2 to 1.0 μm, the particle diameter of the solid polymer particles for forming such a slippery protrusion on the printing surface is within a certain range of 1.0 μm or more. It is desirable that it is adjusted. The reason is that when the particle size of the solid polymer particles is less than 1.0 μm, the solid polymer particles are buried in the printed ink layer and the effect as a lubricant can not be obtained, and conversely, the solid high If the particle size of the molecular particles is too large, the particles remain on the inking roll, plate or blanket during printing, and this gradually accumulates and pirates to deteriorate the printing image quality, or agglomerates on the plate to form protrusions. This is because the so-called hickey phenomenon in which the hollow portion is whitened is caused.

  However, it is difficult to adjust the solid polymer particles to such a desired particle size range and stably disperse them in the ink, and under the present circumstances, plate stains, blanket stains, etc. which are caused due to the inclusion of large particle size particles. To solve the problem completely.

  In the case of high-speed printing, there is also a problem that causes so-called misting in which solid polymer particles are separated and scattered when ink is transferred from a plate. These are due to the low affinity of the solid polymer particles with the ink vehicle, and from this point of view it has become important to modify the surface of the dispersed particles to an interface having an affinity to the vehicle.

  In high-speed offset printing, the printed matter is exposed to high temperatures due to drying, but when the paper surface temperature at this time reaches 100 ° C. or more, the solid polymer particles are melted and flattened, and the target abrasion resistance is It can not be obtained. For this reason, in recent years, solid polymer particles having a high melting point have come to be used, but such solid polymer particles having a high melting point may be refined to an average particle diameter of about 1 to 10 μm It is a more difficult problem.

  The slippage between the printing surface and the back surface or the surface of other substances is also important, and sometimes a wax or the like present as protrusions on the surface of the printing surface may realize a significantly low coefficient of friction, and in such a case, It becomes difficult to stack As a method of adjusting this, although inorganic powder of an appropriate particle size is added to the printing ink, the transparency and glossiness of the printed matter are lowered, and reliable control of the coefficient of friction has not been achieved.

  Further, the same applies to sheet-fed printing of ultraviolet curable ink, and when sufficient drying by ultraviolet irradiation can not be obtained, undried ink or peeled ink adheres to cause a blocking phenomenon in which the printed matter is stained. .

  Also, in gravure printing, after printing on paper or film, the rolled paper or film may be soiled by undried ink on the back surface, and if it is severe, it may stick, or the blocking phenomenon after printing There is a problem that the printed matter surfaces are rubbed due to the contact between the printed matter sides and the printed matter side and the back side.

  In order to solve such problems, at present, especially offset printing ink of oxidative polymerization drying, corn starch, silicone treated corn starch, silicone treated tapioca starch, etc. are sprayed on the printing surface to prevent blocking phenomenon. However, the application of these starches has many problems, as there is a high possibility that dust may cause stains in the printing room, malfunction of equipment, and health problems of operators.

  In addition, it has been practiced to add starch, a silicone-treated starch, etc., which are fine particles in an amount that does not pose a problem in printability, to the printing ink (see, for example, Patent Document 1). However, even with this technology, a sufficient offset prevention effect is not obtained, and the gloss of the printed matter is also severely reduced.

  In recent years, fine particles made of solid polymer such as olefin resin powder and wax are added to offset printing ink including gravure printing to form protrusions that impart non-adhesiveness and lubricity to the printed surface after printing It has been proposed to prevent the adhesion of the printing surface and to improve the abrasion resistance (for example, see Patent Document 2). The fine particles of the solid polymer of this proposal have a volume average particle size of 0.3 to 20 μm, and preferably 0.3 to 15 μm. However, when the volume average particle diameter of such solid polymer particles is 2 μm or less, the blocking preventing effect and the abrasion resistance effect are inferior, and the solid height of a coarse average particle diameter of 10 μm or more is obtained. Molecules have problems in printability, and piling phenomena such as plate residue and blanket residue occur. Further, even if printing can be performed in very small lots, the printed matter is lowered in gloss due to the poor wetting with the ink component only with the large protrusions and the solid polymer such as the olefin resin powder and wax.

  Furthermore, there is a similar proposal in which fine particles having a particle diameter of 2 to 50 times the particle diameter of the olefin-based resin powder are added to the thickness of the print layer (see, for example, Patent Document 3). However, since the thickness of the usually printed offset lithographic printing ink is about 0.2 to 2 μm, the average particle diameter of the olefin resin powder becomes 0.4 μm to 100 μm, and coarse particles having poor printability problems and poor gloss of printed matter It contains. Further, in this document, protective colloid particles are also proposed as particles containing an olefin resin on the surface except for the core of the olefin resin, but this is not sufficient in terms of wear resistance and blocking prevention.

  There is also a proposal for a printing ink containing an acrylic / core-shell polymer (see, for example, Patent Document 4), but the printing ink in this proposal is inferior in the abrasion resistance and the antiblocking effect. There is also a proposal to add a polyvinyl alcohol-based resin powder of a water-soluble polymer to a printing ink (see, for example, Patent Document 5), but in this proposal, the abrasion resistance effect is very inferior.

  As described above, it is desirable that the particle diameter of the solid polymer particles be one having a particle size distribution adjusted to a certain range of 1.0 μm or more. From this point of view, the aqueous dispersion and printing method (see, for example, Patent Document 6) in which addition of a polyolefin wax having an average particle diameter of 0.08 to 0.3 μm is proposed have an abrasion resistance effect and an antiblocking effect. Is significantly inferior.

  Conversely, if the particle size of the solid polymer particles is too large relative to the ink thickness, the particles remain on the inking roll, plate or blanket during printing, and this gradually accumulates and pilings to deteriorate the printing image quality, It causes so-called hickey phenomenon in which the portion where the protrusions are formed coagulate on the plate and white spots. However, it is difficult to prepare solid polymer particles in such a desired particle size range and to stably disperse them in the ink, and at present, pilings such as plate stains and blanket stains which are caused by the inclusion of large particle size particles It has not come to solve the problem completely.

  In addition, there is also a proposal for a printing ink of a spherical aqueous polyolefin wax having a particle diameter of 1.0 to 10.0 μm (for example, see Patent Document 7). However, since the offset lithographic printing ink is oil-based, in the offset lithographic ink using dampening water, the emulsion balance is easily broken. In addition, addition of a surfactant also causes problems in printability, and piling such as plate residue occurs. Furthermore, since the wetting of the ink is bad, the gloss of the printed matter is extremely deteriorated.

  There is also a proposal to add a spherical polymethacrylate as one having UV offset prevention effect (see, for example, Patent Document 8), but the particles have no abrasion resistance effect.

  In the case of high-speed printing, there is also a problem that causes so-called misting in which solid polymer particles are separated and scattered when ink is transferred from a plate. These are due to the low affinity of the solid polymer particles with the ink vehicle, and from this viewpoint, it is important to modify the surface of the dispersed particles to an interface having an affinity to the vehicle.

  With respect to such a point, the present applicant has already improved printing resistance using a printing ink composition using composite particles consisting of wax and inorganic fine particles, and has good abrasion resistance and maintains the gloss of printed matter. The printing ink composition which can be proposed is proposed (for example, refer to patent documents 9). By the way, although this printing ink composition generally has good printability, when it is used for sheet-type ink of normal temperature drying type of oxidation polymerization, it is further characteristic in the blocking effect and the effect of preventing impression cylinder stain. Improvement is required.

JP 01-306481 A Patent No. 3651892 gazette JP, 2010-47670, A Japanese Patent Application Publication No. 2014-514367 Patent No. 5669345 gazette Patent No. 4143165 gazette JP, 2013-216734, A Japanese Patent Application Laid-Open No. 07-331152 Patent No. 4869946

  The present invention has been made to solve such conventional problems, and has as its main object to provide a printing ink composition in which the following problems conventionally encountered in printing ink have been solved.

(1) To provide a printing ink composition which is excellent in abrasion resistance, exhibits an excellent blocking prevention effect, and is free from problems such as plate stains and blanket stains which do not cause a hickey phenomenon.
(2) A printing ink which is added with a finely divided solid polymer particle having a high melting point and which does not cause a plate stain or blanket stain with controlled rubbing of a guide roll with which the printing surface comes in contact with the printing surface during printing and blanket contamination. Providing a composition.
(3) A printing ink composition containing solid polymer components for satisfying printability such as visco-elastic properties is provided which does not deteriorate the surface gloss and transparency.

(4) A printing ink which exhibits excellent abrasion resistance and contains a solid spherical polymer component having an excellent anti-blocking effect, the abrasion resistance even after passing through the process of fixing the printing surface under high temperature. Provided is a printing ink composition in which the blocking property is not reduced.
(5) A printing ink composition containing a solid polymer component exhibiting excellent abrasion resistance and having an excellent antiblocking effect in a printing ink for solvent gravure or an aqueous flexo ink is provided.

  The printing ink composition of the present invention is a printing ink composition containing the composite particles (A) in the printing ink, wherein the composite particles (A) do not dissolve in the printing ink from a resin, a wax or a mixture thereof Solid polymer particles (A-1) and inorganic fine particles (A-2) with an average particle diameter of 5 to 1000 nm attached to the surface, and the volume average particle diameter of the composite particles (A) is 2 to 8 μm Within the range, the volume content of particles having a particle diameter of 10 μm or less is 20% by volume or less, and the sphericity of the composite particles (A) is 0.95 or more.

  The printing ink composition of the present invention is improved in piling and plate residue at the time of printing, which has been a problem when adding solid polymer particles in the past, and wear resistance of the printing surface at the time of printing and after printing Can be significantly reduced and the blocking phenomenon due to the stacking of the printed matter can be significantly reduced.

  In addition, since the inorganic fine particles coat the surface of the solid polymer particles, the affinity with the ink vehicle is good, there is no occurrence of the hicky phenomenon and the like, and in particular, the normal temperature drying type offset printing ink for offset sheet And, since the heat-drying type planographic printing ink for rotary printing offset is not taken by the impression cylinder and the impression cylinder is not soiled, it is possible to give a high gloss print without staining the preprinted print.

  Furthermore, the printing ink composition of the present invention has a remarkable improvement effect on sliding properties even when a small amount of highly sphericity composite particles (A) is added to the ink vehicle, and it seems that the sphericity is less than 0.95. Compared with a printing ink composition using the above composite particles, the addition of a small amount of composite particles can provide the same abrasion resistance and antiblocking performance, and the amount of addition can be greatly reduced. Therefore, compared to the conventional composite particles, the printed matter can be provided without lowering the transparency and the glossiness, and improvement in printability such as piling can also be obtained.

  Furthermore, even if solid polymer particles having a high melting point are used, the volume average particle diameter can be refined to 2 to 8 μm by the action of the inorganic fine particles.

7 is an electron micrograph of the composite particle obtained in Example 2.

The present invention is a printing ink composition containing composite particles (A) in a printing ink as described above, and is characterized in particular by the composite particles (A). Hereinafter, the present invention will be described in more detail.
First, the printing ink used in the present invention is not particularly limited as long as it is a known printing ink, and among them, offset ink is preferable.

  Examples of the offset ink used here include an oxidation polymerization type offset lithographic ink generally used, an ultraviolet-curable type offset lithographic ink, and a solvent type gravure ink.

  For example, as an oxidation polymerization type offset lithographic ink, pigments such as carbon black of black ink, phthalocyanine blue of black ink, brilliant carmine 6B of red ink, pigment yellow of pigment yellow of yellow ink, quinacridone pigments, etc. % By mass, 20-30% by mass of synthetic resin components such as rosin modified phenolic resin, alkyd resin, petroleum resin etc. as fixing components, semi-drying oil or drying oil such as soybean oil, linseed oil, soybean oil fatty acid butyl ester etc. An ink composed of 40 to 40% by mass, 20 to 30% by mass of mineral oil such as aroma free, and 1 to 10% by mass of auxiliary agent such as a dryer or an antioxidant can be used.

  Also, for example, as ultraviolet curable lithographic ink, 15 to 25% by mass of pigment used in oxidative polymerization type lithographic ink, fixing agent may be various acrylic prepolymers and monomers (for example, bisphenol A diglycidyl ether diacrylate, 60 to 70 mass% of a mixture of dipen erythritol pentaacrylate and dipentaerythritol hexaacrylate, ditrimethylolpropane tetraacrylate, ethylene oxide or propylene oxide adduct of trimethylolpropane triacrylate, methacrylate, etc., photopolymerization initiator ( For example, as a radical reaction type, alkylphenone type, acyl phosphine oxide type, oxime ester type, intramolecular hydrogen abstraction type, cation reaction type, etc. 10 wt%, a polymerization inhibitor and inks hardness adjustment bentonite such as 5 to 10% by weight as auxiliaries, in the configured ink can be used.

  As gravure ink, the pigment used for offset lithographic ink can be used, and the addition amount is 5 to 30% by mass, as an extender pigment, for example, fatty acid-treated calcium carbonate, rosin acid-treated calcium 0 to 5% by mass, fixing agent (For example, synthetic resin such as nitrocellulose, butyral resin, alkyd resin, acrylic resin, rosin type or mixed resin thereof) 20 to 40% by mass, the solvent has a low boiling point and is compatible with the resin (for example, toluene) , Ethyl acetate, isopropyl alcohol, propyl alcohol, butyl alcohol, methylcyclohexane, cyclohexanone, ethylene glycols, their mixtures, etc.) 40 to 70% by mass, adjuvants such as anti-settling agents 0 to 10% by mass Can be used.

  The composite particles (A) to be used in the present invention usually adhere (including a form in which a part is buried) so that the inorganic fine particles (A-2) substantially cover the surface of the solid polymer particles (A-1) And the volume average particle size thereof is in the range of 2 to 8 μm. Here, "coating" means that a large number of inorganic fine particles (A-2) are scattered on the surface of the solid polymer particles (A-1) to such an extent that the above-mentioned blocking phenomenon and hicky phenomenon are suppressed. It means that it does not have to be completely covered.

  The "volume average particle diameter" in the present specification is a value measured by a Coulter Counter manufactured by Beckman Coulter. When the average particle diameter of the composite particles (A) contained in the printing ink composition is less than 2 μm, it does not act as an active ingredient for imparting abrasion resistance and blocking property, which is the original purpose of the present invention, and thus it is not preferable. If the average particle size exceeds 8 μm, it is effective for improving the abrasion resistance and blocking property, but it may be pirated on a plate, blanket, or inking roll to cause plate stains, etc. It is not preferable because the gloss and the transparency are deteriorated. Even if the average particle size is 8 μm or less, it is not preferable because particles having a broad particle size distribution and containing more than 20 vol% of particles exceeding 10 μm are easy to be pirated. In particular, sphericity is important, and when the sphericity of spherical particles is 0.95 or more, the abrasion resistance is dramatically improved and the antiblocking effect is also excellent, and when the number of particles of 10 μm or more increases, the plate is clearly In the ink composition of the present invention, there is hardly any trouble on the printing machine up to 20% by volume of particles of 10 μm or more, which causes plate stains and the like by piling on a blanket, or inking roll.

  As the solid polymer particles (A-1) used in the present invention, resin particles such as fluorocarbon resin, polystyrene, polyacetal, epoxy resin, silicone resin and the like, natural wax, synthetic wax, polyethylene wax, polypropylene wax, ester wax, calcium stearate For example, metal soaps such as zinc stearate, waxes such as amide wax, particles made of this composite, and particles having an average particle diameter of 0.1 to 30 μm. As these particles, those having a melting point of 80 ° C. to 300 ° C. or crosslinked products having no melting point can be used, and in particular, an oxidized polyethylene wax having a melting point of 120 ° C. or more and an acid value of 10 or more is preferable. The wax used in the present invention is a generic term for substances containing long-chain hydrocarbon chains and rapidly decreasing at a certain temperature at viscosity, and in the present invention, the number of carbon atoms in the hydrocarbon chain is at least 10 or more. Waxes containing paraffin chains are suitable.

In addition, the solid polymer particle (A-1) has a melting point of 120 ° C. or higher, and a needle having a weight of 100 g applied according to JIS K-2235-5.4 is a sample at 25 ° C. for 5 seconds. Waxes having a penetration of 2.0 or less, expressed in units of 10 ⁻¹ mm as the depth of penetration into the membrane, are preferred.

  As the inorganic fine particles (A-2) used in the present invention, metal oxides selected from silica, alumina, titania, bentonite, montmorillonite and the like, metal nitrides such as aluminum nitride and boron nitride, silicon carbide and the like Fine particles consisting of metal carbide, metal sulfate such as barium sulfate and calcium sulfate, calcium carbonate, sulfide including carbon disulfide, fluoride or one or a mixture of fluoride such as fluorite, fluorocarbon, etc. primary average particle diameter Is from 5 nm to 1000 nm. The average particle diameter of the inorganic particles (A-2) is a value measured by Nanotrac UPA EX manufactured by Nikkiso Co., Ltd. while dispersed in water. In addition, particles having a particle diameter of 100 nm or less are usually measured as a particle diameter including aggregated particles. Since these primary average particle sizes may be present in a state of being attached to the surface of the composite particles (A), the particle sizes in the state of being actually used are measured by an electron microscope image of the particle surface.

  The sphericity measurement was carried out by measuring the circularity with an FPIA-3000 shape measuring instrument (manufactured by Malvern Division, trade name). Originally, it is necessary to determine whether the sphericity is spherical or not, but this measuring device measures an image in which three-dimensional particles are dropped in two dimensions, and is obtained by measuring a large number of particles, for example, 300,000. It can be regarded as substantially sphericity because it is an average of numerical values to be circularity, and this method is also widely used in this field.

  The composite particles (A) are prepared by blending the resin or solid polymer particles (A-1) and the inorganic fine particles (A-2) as a matrix in a desired ratio, then using a Henschel mixer, sand grinder, bead mill, attritor, ball mill Using a kneader, a roll mill, a twin screw kneader, a tornado mill, a jet mill, a pin mill, a mechanical mill, etc., and mix at a desired temperature or less under high speed and high shear force. By this mixing, a composite in which inorganic particles are uniformly coated on the surface of resin particles or wax particles is formed. Spheronization processing equipment for spheronization gives spherical microparticles. For example, the general spray drying method, the spray drying method using supercritical carbon dioxide, the emulsification method using an autoclave, and Meteor Rainbow (Sphericalized by Nippon Pneumatic Mfg. Co., Ltd., etc., raised the circularity to 0.95 or more). Composite particles (A) can be obtained.

  In addition, in the mixing step, fine particles are generated due to crushing and abrasion of the solid polymer particles (A-1), and inorganic fine particles are further attached to the surface thereof. The particle size can be adjusted relatively freely. Although the composite particles (A) having a circularity of 0.95 or more obtained by such mixing and spheroidizing steps are often substantially covered with the inorganic fine particles (A-2), For example, in the case of composite particles formed by recombination of wear powder, inorganic fine particles are also present inside the composite particles.

  In addition, when solid polymer particles (A-1) having high molecular weight and strong visco-elasticity are used, it is generally difficult to stably miniaturize the particles, but in the above embodiment, the inorganic fine particles (A-2) Because of the mixing, miniaturization can be easily and stably performed such that the volume average particle diameter of the composite particles (A) obtained by the action is 2 to 8 μm. Therefore, the composite particle (A) of the present invention can be stably produced by a simple operation.

  At this time, it is preferable to contain and mix an inorganic fine particle (A-2) in 0.5-50 mass parts with respect to 100 mass parts of solid polymer particles (A-1), and 2-20 mass parts Is more preferable. By mixing in such a range, inorganic fine particles can be dispersed on the surface of the solid polymer particles (A-1) for production.

  The composite particles (A) having a sphericity of 0.95 or more obtained in this manner are adjusted to a desired particle size through a classification step and added to the printing ink. At the time of addition, it is directly added to the printing ink, pre-mixed in advance in the printing ink vehicle to form a paste, and this paste is added to the ink in the process of producing the ink, or the like. It can be added, and good results can be obtained by any method. The addition of the printing ink to the composite particles can be carried out with a kneader, roll mill, bead mill or the like.

Examples of the present invention will be described below.
Composite particles (A) having a sphericity of 0.95 or more added to the printing ink in each example are simply described as composite particles.

Example 1
After blending 1.5 parts by mass of the following composite particles A with 100 parts by mass of printing ink for heating / drying type offset rotary press (hereinafter, heating / drying type ink), they are mixed by a three-roll mill to produce an ink 1 did.
Composite particle A: One in which 10 parts by mass of silica powder having a primary average particle diameter of 10 nm is contained in 100 parts by mass of oxidized polyethylene particles having a melting point of 135 ° C. and an acid value of 30. The sphericity of this composite particle A is 0.97, the average particle diameter is 5 μm, and 10 vol% of particles having a particle diameter of 10 μm or more are contained.

(Example 2)
After blending 1.5 parts by mass of the following composite particles B with respect to 100 parts by mass of the heat-drying type ink, they were mixed by a three-roll mill to prepare an ink 2.
Composite particle B: One in which 30 parts by mass of silica powder having a primary average particle diameter of 10 nm is contained in 100 parts by mass of polyethylene particles having a melting point of 130 ° C. The sphericity of this composite particle B is 0.95, the average particle diameter is 3 μm, and 5 vol% of particles having a particle diameter of 10 μm or more are included.

(Example 3)
After blending 1.5 parts by mass of the following composite particles C with respect to 100 parts by mass of the heat-drying type ink, they were mixed by a three-roll mill to prepare an ink 3.
Composite particle C: 100 parts by mass of amide wax particles having a melting point of 135 ° C. and 30 parts by mass of silica powder having a primary average particle diameter of 10 nm. The sphericity of this composite particle C is 0.95, the average particle diameter is 5 μm, and it contains 5% by volume of particles having a particle diameter of 10 μm or more.

(Example 4)
After 1.5 parts by mass of the composite particle D was blended with 100 parts by mass of the heat-drying ink, the mixture was mixed by a three-roll mill to prepare an ink 4.
Composite particles D: 70 parts by mass of polytetrafluoroethylene particles having a melting point of 310 ° C. and 30 parts by mass of oxidized PE WAX having a melting point of 120 ° C. are mixed and then heated to a temperature above the melting point of oxidized PE WAX and spheroidized by a spheronizer. Containing 20 parts by mass of silica powder with a particle size of 10 nm. This composite particle D has a sphericity of 0.95, an average particle diameter of 4 μm, and contains 5% by volume of particles having a particle diameter of 10 μm or more.

(Example 5)
After blending 1.5 parts by mass of the following true spherical composite particles E with respect to 100 parts by weight of the heat-drying type ink, they were mixed by a three-roll mill to prepare an ink 5.
Composite particle E: One in which 10 parts by mass of talc powder having a primary particle diameter of 500 nm is contained with respect to 100 parts by mass of polyethylene particles having a melting point of 125 ° C. The sphericity of this composite particle E is 0.96, the average particle diameter is 5 μm, and it contains 4% by volume of particles having a particle diameter of 10 μm or more.

(Example 6)
After blending 1.5 parts by mass of the following composite particles F with respect to 100 parts by mass of the normal temperature drying type offset sheet-fed printing ink (hereinafter, normal temperature drying type ink), they were mixed by a three roll mill to prepare an ink 6 .
Composite particle F: Polyethylene oxide particles having a melting point of 120 ° C. and an acid value of 30; penetration at 25 ° C. <1.0), 20 parts by mass of alumina powder having a primary particle diameter of 10 nm and 10 mass of bentonite powder having a primary particle diameter of 1000 nm Contain the part. The sphericity of this composite particle F is 0.95, the average particle diameter is 8 μm, and 20 vol% of particles having a particle diameter of 10 μm or more are included. The “penetration” is based on JIS K-2235-5.4. A needle with a weight of 100 g penetrates into the sample film at 25 ° C. for 5 seconds in a unit amount of 10 ⁻¹ mm. It is represented as

(Example 7)
After blending 1.5 parts by mass of the following composite particles G with respect to 100 parts by mass of the normal temperature drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 7.
Composite particle G: 100 parts by mass of polytetrafluoroethylene particles having a melting point of 310 ° C. coated with 5 parts by mass of fatty acid-treated calcium carbonate powder having a primary particle diameter of 80 nm. The sphericity of this composite particle G is 0.95, the average particle diameter is 4 μm, and 6 vol% of particles having a particle diameter of 10 μm or more are included.

(Example 8)
After blending 1.5 parts by mass of the following composite particles H with respect to 100 parts by mass of the normal temperature drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 8.
Composite particle H: 10 parts by mass of silica powder having a primary average particle diameter of 10 nm and 5 parts by mass of quaternary ammonium salt of montmorillonite in 100 parts by mass of Fischer-Tropsch wax (Fisher-Tropsch Wax; manufactured by Sazol wax) having a melting point of 105 ° C. The part was covered. The sphericity of this composite particle H is 0.97, the average particle diameter is 7 μm, and 20 vol% of particles having a particle diameter of 10 μm or more are included.

(Example 9)
After blending 1.5 parts by mass of the following composite particles I with respect to 100 parts by mass of the normal temperature drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 9.
Composite particle I: 100 parts by mass of polyethylene particles having a melting point of 125 ° C. coated with 10 parts by mass of rosin acid-treated calcium carbonate having a primary particle size of 50 nm. The sphericity of this composite particle I is 0.96, the average particle diameter is 9 μm, and 20% by mass of particles having a particle diameter of 10 μm or more are contained.

(Example 10)
After blending 1.5 parts by mass of the following composite particles J with 100 parts by mass of the ultraviolet curable offset sheet-fed printing press ink, they were mixed by a three-roll mill to prepare a printing ink composition 10.
Composite particle J: 100 parts by mass of polytetrafluoroethylene particles having a melting point of 310 ° C. coated with 10 parts by mass of silica powder having a primary particle diameter of 10 nm. The sphericity of this composite particle J is 0.95, the average particle diameter is 5 μm, and 7 vol% of particles having a particle diameter of 10 μm or more are contained.

(Example 11)
The following composite particles K and 0.7 parts by mass of the composite particles A of Example 1 were blended with 100 parts by mass of the normal temperature drying type aqueous gravure ink, and then they were mixed by a three-roll mill to obtain an ink composition 11 Was produced.
Composite particle K: 100 parts by mass of polypropylene particles having a melting point of 135 ° C. and 30 parts by mass of silica powder having a primary particle diameter of 10 nm. The sphericity of this composite particle K is 0.95, the average particle diameter is 5 μm, and it contains 3% by volume of particles having a particle diameter of 10 μm or more.

(Example 12)
The following composite particles L and 1 part by mass of the composite particles A of Example 1 were blended with 100 parts by mass of the evaporation-drying type solvent gravure ink, and then they were mixed by a bead mill to prepare a printing ink composition 12 .
Composite particle L: 100 parts by mass of ethylene-vinyl acetate copolymer wax having a melting point of 102 ° C. coated with 30 parts by mass of silica powder with a primary particle diameter of 10 nm. The sphericity of this composite particle L is 0.96, the average particle diameter is 6 μm, and 18 vol% of particles having a particle diameter of 10 μm or more are included.

(Comparative example 1)
After 1.5 parts by mass of the following particles M were blended with 100 parts by mass of the heat-drying ink, they were mixed by a three-roll mill to prepare a printing ink composition 13.
Particles M: melting point 130 ° C., sphericity 0.91, average particle diameter 6 μm, and containing 15% by volume of particles with a particle diameter of 10 μm or more.

(Comparative example 2)
After blending 1.5 parts by mass of the following particles N with respect to 100 parts by mass of the heat-drying ink, they were mixed by a three-roll mill to prepare a printing ink composition 14.
Particles N: Melting point 110 ° C., sphericity 0.85, average particle diameter 7 μm, containing 20% by volume of particles with a particle diameter of 10 μm or more.

(Comparative example 3)
After blending 1.5 parts by mass of the following particles P with respect to 100 parts by mass of the heat-drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 15.
Particles P: Melting point 130 ° C., average particle diameter 6 μm, sphericity 0.91 and particles 10 μm or more in particle size 10% by volume.

(Comparative example 4)
After blending 1.5 parts by mass of the following particles Q with respect to 100 parts by mass of the normal temperature drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 16.
Particles Q: Polyethylene particles having a melting point of 120 ° C., particles having a sphericity of 0.90, an average particle diameter of 5 μm, and containing 10% by volume of particles having a particle diameter of 10 μm or more.

(Comparative example 5)
After blending 1.5 parts by mass of the following composite particles R with respect to 100 parts by mass of the normal temperature drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 14.
Composite particle R: 100 parts by mass of polyethylene particles having a melting point of 120 ° C. coated with 10 parts by mass of silica powder having a primary average particle diameter of 12 nm. This composite particle N has a sphericity of 0.85, an average particle diameter of 6 μm, and contains 20% by volume of particles having a particle diameter of 10 μm or more.

(Comparative example 6)
After blending 1.5 parts by mass of the following true spherical particles S with respect to 100 parts by mass of the normal temperature drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 15.
Particles S: Polyethylene particles having a melting point of 130 ° C., having a sphericity of 0.95, an average particle diameter of 8 μm, and containing 23% by volume of particles having a particle diameter of 10 μm or more.

(Comparative example 7)
After blending 1.5 parts by mass of the following composite particles T with respect to 100 parts by mass of the normal temperature drying type ink, they were mixed by a three-roll mill to prepare a printing ink composition 16.
Composite particle T: 100 parts by mass of Fischer-Tropsch wax having a melting point of 105 ° C. coated with 10 parts by mass of silica powder having a primary average particle diameter of 10 nm and 10 parts by mass of quaternary ammonium salt of montmorillonite. The sphericity is 0.93, the particle average particle diameter is 8 μm, and 22 volume% of particles having a particle diameter of 10 μm or more are included.

(Comparative example 8)
After 2 parts by mass of the following particles U were blended with 100 parts by mass of the ultraviolet curable offset sheet-fed printing press ink, they were mixed by a three-roll mill to prepare a printing ink composition 17.
Particles U: polytetrafluoroethylene particles having a melting point of 310 ° C., having a sphericity of 0.86 and an average particle diameter of 3 μm, and containing 1% by volume of particles having a particle diameter of 10 μm or more.

(Comparative example 9)
After blending 1.5 parts by mass of the following particles W with 100 parts by mass of the evaporation-drying type solvent gravure ink, they were mixed by a bead mill to prepare a printing ink composition 18.
Particles W: Polyethylene particles having a melting point of 120 ° C., having a sphericity of 0.92, an average particle diameter of 10 μm, and containing 22% by volume of particles having a particle diameter of 10 μm or more.

  The inks obtained in Examples and Comparative Examples were tested by printing on paper by a normal temperature drying method and an ultraviolet curing method of a rotary offset printing sheet-fed printing press or a gravure printing press. The test results are shown in Table 1.

Evaluation printing ink:
As printing ink before mixing a true spherical composite particle etc. in the above-mentioned example and comparative example, a base ink (red ink, twill ink) for offset rotary offset lithography various performance evaluation, and a base for performance evaluation of offset sheet-fed various lithography An ink (red ink, twill ink), an offset sheet-fed lithographic UV base ink for evaluating various performances (red ink, twill ink), and a gravure various performance evaluation base ink (red ink, twill ink) were used.

Printing conditions:
Printing was performed using the following offset sheet-fed lithographic printing press (also used as a printing test machine for lithographic printing ink for offset-off rings), and printing suitability (pile evaluation) and printed matter evaluation were performed. After printing, the sheet-fed ink composition was stacked on a stick and dried at normal temperature to obtain a printed matter evaluation piece. Blocking evaluation is as described below. After printing, the UV-drying ink composition was evaluated as a printed matter evaluation piece by the following UV irradiator. The pressure cylinder staining evaluation was evaluated only for the sheet-fed ink composition. The heat drying of the ink for off-rings takes out the printed matter immediately after printing, and a heating and drying apparatus (according to the printed matter evaluation piece).

・ Kiku half-cut four-color offset printing machine (Sakurai Graphic Systems (made), CTP version: SCREEN PT-R4300, printing speed: 10,000 sheets / Hr)
・ UV irradiator (for UV ink): TUJ-690 (made by Toho Seiki Co., Ltd.)
・ Drying device (off-wheel printing drying device: device name PM-9000D SMT (made by company))
Test conditions:
· Hot air temperature 200 ° C, paper surface temperature 120 ° C
・ At the time of blocking evaluation (paper surface temperature 100 ° C)

  The ink compositions obtained in the respective Examples and Comparative Examples were printed using an offset printing machine or a gravure printing machine, and the printing appropriateness evaluation and the printed matter evaluation were performed. The test results are shown in Table 1.

The test results in the table are the results evaluated by the following methods.
Piling resistance:
After printing 3000 sheets of each of the printing ink composition for oxidation-polymerization type sheet-fed, the heat-drying type off-ring ink and the ultraviolet curing drying ink on an offset printing machine, a plate, a blanket and an inking for each printing Evaluate by the presence or absence of deposits on the roll surface and the degree of soiling. That is, no precipitation of solid polymer is observed, and a printed surface that maintains the same image quality as the initial printing is regarded as ○, and the case where the solid polymer is precipitated and the printing surface is deteriorated is x, The middle is marked △.
In addition, in the case of gravure printing, no precipitation of solid polymer is observed in the cylinder made by the gravure printing machine at the time of printing, and the printing surface maintains the same image quality as in the initial printing stage. The case where molecules were precipitated and the printing surface was degraded was marked x, and the middle was marked Δ.

Pressure-resistant cylinder stain resistance (evaluated for sheet-fed printing ink composition):
After printing 3000 sheets on an offset sheet-fed lithographic printing press, stack it up and leave it for a day, turn it over to print the back side, and to what extent the printing ink of the first printing adheres to the metal impression cylinder and becomes soiled Determine visually.胴 Good impression with few stains on the impression cylinder 、, Slight stains but no problems を, Slight stains 激 し く, Severe stains ×.

Blocking resistance:
Immediately after printing printed materials for sheet-fed printing ink compositions, the printed surfaces are overlapped and left to stand for 24 hours at a room temperature of 40 ° C. and a humidity of 60% under a load of 500 g / cm ² . Was visually evaluated. Those with no offset were 、, those with little appearance were ○, those with some appearance were △, and those with many offsets were ×.
For the evaluation of the off-ring ink composition, after printing, the print is half-dried so that the sheet temperature is 100 ° C. by blowing hot air at 200 ° C. Immediately after that, the printing surfaces are overlapped to print the sheet ink composition It was evaluated under the same conditions as above.

Wear resistance of printed matter:
After drying the printed matter printed on a special art paper for 24 hours, the room temperature drying type ink composition rubs the solid print area under a load of 500 g for 20 reciprocations with a Toyo Seiki Kakusho friction tester, and the image by abrasion is printed The degree of deterioration was evaluated in five steps. There were few rubbed stains, good ones ◎, very slight rubbed stains, 、, slightly rubbed dirt, Δ, slightly rubbed dirt a little x, and strongly scuffed dirt x ×.
For evaluation of off-ring ink composition, print on pearl coated paper using a sheet-fed printing press as evaluation printer, blow hot air at 200 ° C to make the paper surface temperature 120 ° C, and then cool the paper surface to normal temperature The evaluation pieces were used as the evaluation pieces, and the abrasion resistance was evaluated in five steps in the same manner as the normal temperature drying type ink.
The UV ink composition is printed on a sheet of paper and then printed using a printed matter as a test piece with a UV irradiator. The solid print area is abraded under load of 500 g under the condition of 500 cycles of back and forth. did.

Print gloss rating:
Measured by the ratio (%) of the incident light intensity at an incident angle of 60 degrees to the solid printing surface after drying and the reflected light intensity at a reflection angle of 60 [glossmeter: GM-3D, manufactured by Murakami Color Research Laboratory Based on this result as a reference, it was comprehensively evaluated whether it was a high gloss printed matter by visual evaluation.
A high-gloss, good printed product was rated as ◎, a somewhat good type as ○, a somewhat inferior type as Δ, and a poor type as x.

  In addition, the detailed composition of the printing ink used by the above-mentioned Example and comparative example is as follows.

  The base ink for evaluating the performance of offset rotary offset lithography has the following constitution, and the used rosin-modified phenolic resin varnish is obtained by the following constitution.

  (Red ink) Carmine 6B (product name: ECR101, Dainichi Seika Kogyo Co., Ltd.) 8 to 22% by mass, rosin-modified phenolic resin varnish 60 to 70% by mass, AF-solvent 7 (trade name, Nippon Oil Co., Ltd. A) Solvent: 10 to 20% by mass, and other additives 5 to 10% by mass. In this formulation, particle size measurement (according to JIS K 5701 4.3 2000) was carried out using a bead mill and 3 rolls with a grind gauge: Toyo Seiki Seisakusho (made), and dispersion was carried out to a particle size of 5.0 μm or less. Final adjustment: Tack value (Incometer meter Toyo Seiki Seisakusho (made): 32 ° C, value after 1 minute according to JIS K 5701 4.2 2000) is adjusted to 4 to 7, and the ink Fluidity: It was adjusted to be 38 to 42 mm at a flow value (a spread meter measuring instrument, manufactured by Toyo Seiki Seisaku-sho, Ltd .: JIS K 5701 4.1 2000 at 25 ° C., diameter value after 1 minute).

  (藍 ink) Phthalocyanine blue (product name: ECB-303, Dainichi Seika Kogyo Co., Ltd.) 18 to 22% by mass, rosin modified phenolic resin varnish 60 to 70% by mass, AF-solvent 7 (trade name, Nippon Oil Co., Ltd.) Solvent (made by Co., Ltd.) 10 to 20% by mass, and other additives 5 to 10% by mass. In this formulation, particle size measurement (according to JIS K 5701 4.3 2000) was carried out using a bead mill and 3 rolls with a grind gauge: Toyo Seiki Seisakusho (made), and dispersion was carried out to a particle size of 5.0 μm or less. Final adjustment: Tack value (Incometer meter Toyo Seiki Seisakusho (made): 32 ° C, value after 1 minute according to JIS K 5701 4.2 2000) is adjusted to 4 to 7, and the ink Fluidity: It was adjusted to be 38 to 42 mm at a flow value (a spread meter measuring instrument, manufactured by Toyo Seiki Seisaku-sho, Ltd .: JIS K 5701 4.1 2000 at 25 ° C., diameter value after 1 minute).

  Formulation of rosin-modified phenolic resin varnish: 35 to 45% by mass of TAMANOL 420 (product name, Arakawa Chemical Industries, Ltd.), 1 to 5% by mass of alkyd resin HL-17 (product name, Toshin Fat & Co., Ltd.) White drawn oil (Nisshin Oil Co., Ltd.) 1 to 10% by mass, TX-100 (Nab Corporation (made)) 10 to 20% by mass, AF-solvent 4 (trade name, solvent manufactured by Nippon Oil Co., Ltd.) ) 35 to 45 mass%, ALCH (trade name: Kawaken Fine Chemical Co., Ltd.) 0.5 to 2 mass% are heated and mixed at 180 ° C. to 220 ° C. to dissolve the resin, and the viscosity is 25 by cone and plate viscosity The viscosity is adjusted to 30 to 40 Pa · s at a shear rate of 100 / s and the varnish is used as a varnish.

  The base ink for offset sheet-fed lithographic various performance evaluation has the following constitution, and the used rosin modified phenolic resin varnish is obtained by the following constitution.

  (Red ink) Carmine 6B (product name: ECR101, Dainichi Seika Kogyo Co., Ltd.) 8 to 22% by mass, rosin modified phenolic resin varnish 60 to 70% by mass, AF-solvent 6 (trade name, Nippon Oil Co., Ltd. A) Solvent: 5 to 10% by mass, cobalt, 1% by mass of dry accelerator of manganese complex (trade name: Petrodryer EF, T & K TOKA (made)), and 5 to 10% by mass of other additives. In this formulation, particle size measurement (according to JIS K 5701 4.3 2000) was carried out using a bead mill and 3 rolls with a grind gauge: Toyo Seiki Seisakusho (made), and dispersion was carried out to a particle size of 5.0 μm or less. Final adjustment: Tack value (Incometer meter Toyo Seiki Seisakusho (made): 32 ° C, value after 1 minute according to JIS K 5701 4.2 2000) is adjusted to 6 to 9, and the ink Fluidity: It was adjusted so as to be 37 to 40 mm at a flow value (a spread meter measuring instrument, manufactured by Toyo Seiki Seisakusho (manufactured by Toyo Seiki Co., Ltd.): diameter value after 1 minute at 25 ° C. according to JIS K 5701 4.1 2000).

  (藍 ink) Phthalocyanine blue (product name: ECB-303, Dainichi Seika Kogyo Co., Ltd.) 18 to 22% by mass, rosin modified phenolic resin varnish 60 to 70% by mass, AF-solvent 6 (trade name, Nippon Oil Co., Ltd.) Solvent manufactured by Co., Ltd.) 5 to 10% by mass, cobalt, 1% by mass of dry accelerator of manganese composite (trade name: Petrodryer EF, T & K TOKA (made)), and 5 to 10% by mass of other additives. In this formulation, particle size measurement (according to JIS K 5701 4.3 2000) was carried out using a bead mill and 3 rolls with a grind gauge: Toyo Seiki Seisakusho (made), and dispersion was carried out to a particle size of 5.0 μm or less. Final adjustment: Tack value (Incometer meter Toyo Seiki Seisakusho (made): 32 ° C, value after 1 minute according to JIS K 5701 4.2 2000) is adjusted to 6 to 9, and the ink Fluidity: It was adjusted so as to be 37 to 40 mm at a flow value (a spread meter measuring instrument, manufactured by Toyo Seiki Seisakusho (manufactured by Toyo Seiki Co., Ltd.): diameter value after 1 minute at 25 ° C. according to JIS K 5701 4.1 2000).

  Formulation of rosin modified phenolic resin varnish: 30 to 40 mass% of TAMANOL 463 (product name, Arakawa Chemical Industries, Ltd.), 1 to 5 mass% of alkyd resin HL-17 (trade name, Toshin Fat (manufactured by Toshin Yushi Co., Ltd.)) White drawn oil (Nisshin Oil Co., Ltd.) 25-35% by mass, soybean oil fatty acid N-butyl ester SFB-2 (trade name, Toshin Yushi (product)) 10-20% by mass, AF-sorbent No. 5 (product Brand name, 15-25 mass% of Nippon Oil Co., Ltd. solvent, 0.5-1 mass% of Octopal Aluminum T (trade name, Hope Pharmaceutical Co., Ltd.), heated and mixed at 180 ° C.-230 ° C. resin The viscosity is adjusted to a viscosity of 35 to 40 Pa · s at a shear rate of 100 / s as a cone and plate type viscosity at 25 ° C. to make a varnish.

  As the base inks (red ink, black ink) for offset sheet-fed lithographic UV various performance evaluation, those having the following configurations were used.

  (Red ink) Carmine 6B (product name: ECR101, manufactured by Dainichi Seika Kogyo Co., Ltd.) 20 to 25% by mass, a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (product name: KAYARAD DPHA, Nippon Kayaku Co., Ltd. 20-30 mass% of a company (made), 20-30 mass% of bisphenol A diglycidyl ether diacrylate (trade name: CN121, Arkema (made)), ditrimethylolpropane tetraacrylate (product name: KAYARAD T-1420 (T) 5) to 10% by mass, photopolymerization initiator: 2-methyl-1- [4- (methylthio)]-2-monophorinopropan-1-one (product name: IRUGACURE 907, BASF ( Made from 5) to 10% by mass, and from 1 to 10% by mass of other additives Become. In this formulation, particle size measurement (according to JIS K 5701 4.3 2000) was carried out using a bead mill and 3 rolls with a grind gauge: Toyo Seiki Seisakusho (made), and dispersion was carried out to a particle size of 5.0 μm or less. Final adjustment: Tack value (Incometer, manufactured by Toyo Seiki Seisakusho (manufactured by Toyo Seiki Co., Ltd.): 32 ° C., value after 1 minute according to JIS K 5701 4.2 2000) adjusted to 5 to 8 and ink The flowability was adjusted to 35 to 38 mm with a flow value (a spread meter measuring instrument, manufactured by Toyo Seiki Seisaku-sho (manufactured by Toyo Seiki Co., Ltd.): 25 ° C., diameter value after 1 minute according to JIS K 5701 4.1 2000).

  (藍 ink) Phthalocyanine blue (product name: ECB-303, manufactured by Dainichi Seika Kogyo Co., Ltd.) 20 to 25% by mass, mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (product name: KAYARAD DPHA, Nipponized Pharmaceutical Co., Ltd. (made) 20-30 mass% bisphenol A diglycidyl ether diacrylate (product name: CN121, Arkema (made)) 20-30 mass%, ditrimethylolpropane tetraacrylate (product name: KAYARAD T-1420 (product name) T), Arkema (made) 5 to 10% by mass, Photopolymerization initiator: 2-methyl-1- [4- (methylthio)]-2-monophorinopropan-1-one (product name: IRUGACURE 907: BASF) (Made) 5 to 10% by mass, other additives 1 to 10 It consists of%. In this formulation, particle size measurement (according to JIS K 5701 4.3 2000) was carried out using a bead mill and 3 rolls with a grind gauge: Toyo Seiki Seisakusho (made), and dispersion was carried out to a particle size of 5.0 μm or less. Final adjustment: Tack value (Incometer, manufactured by Toyo Seiki Seisakusho (manufactured by Toyo Seiki Co., Ltd.): adjusted to 5-8 at 32 ° C., 1 minute according to JIS K 5701 4.2 2000), and ink The flowability was adjusted to 35 to 38 mm with a flow value (a spread meter measuring instrument, manufactured by Toyo Seiki Seisaku-sho (manufactured by Toyo Seiki Co., Ltd.): 25 ° C., diameter value after 1 minute according to JIS K 5701 4.1 2000).

Base ink for gravure performance evaluation (red ink)
Lake red C # 405 (F) (product name, Dainichi Seika Kogyo Co., Ltd.) red pigment 10 to 20% by mass, nitrifying cotton dope (trade name: nitrone NC dope NO.5, Taisei Chemical Works (product)) 20 -40% by mass, Imma-99% IPA modified ethanol (product name, Imazu Pharmaceutical Co., Ltd. (made)) 15-25% by mass, ethyl acetate 15-25% by mass, isopropyl alcohol 10-20% by mass, other additives 1- It consists of 10% by mass.
In this formulation, the pigment was subjected to particle size measurement (according to JIS K 5701 4.3 2000) with a grind gauge: Toyo Seiki Seisakusho Co., Ltd. (manufactured by Toyama Seiki Co., Ltd.) and dispersed to a particle size of 20 μm or less. Zaan cup No. 3 (trade name, manufactured by Reikasha Co., Ltd.) (following the viscosity measurement method according to the flow cup of JIS K 5600-2-2) in the combination of the above solvents so as to be 15 to 20 seconds Adjusted.

Base ink for gravure performance evaluation (評 価 ink)
Phthalocyanine blue (Product name: ECB-303, manufactured by Dainichi Seika Kogyo Co., Ltd.) 10 to 20% by mass, Nitrified cotton dope (trade name: Nitron NC dope No. 5, Daisei Chemical Co., Ltd.) 20 to 40 % By mass, Imma ヅ 99% IPA modified ethanol (trade name, Imazu Pharmaceutical Co., Ltd.) 15 to 25% by mass, ethyl acetate 15 to 25% by mass, isopropyl alcohol 10 to 20% by mass, and other additives 1 to 10% It consists of%.

  In this formulation, the pigment was subjected to particle size measurement (according to JIS K 5701 4.3 2000) with a grind gauge: Toyo Seiki Seisakusho Co., Ltd. (manufactured by Toyama Seiki Co., Ltd.) and dispersed to a particle size of 20 μm or less. Zaan cup No. The viscosity was adjusted by post-addition with the combination of the above solvents so as to be 15 to 20 seconds (based on the viscosity measurement method according to the flow cup of JIS K 5600-2-2) by No. 3 (manufactured by Rigosha Co., Ltd.) .

  As mentioned above, the printing ink composition of this invention can improve the piling and plate | version | printing residue at the time of printing, becomes the outstanding printed matter which improved the abrasion resistance of the printing surface at the time of printing, and after printing, and blocking effect effectively. It has been found that it is possible to suppress, and also to prevent impression cylinder dirt, and to obtain high-gloss printed matter.

  The present invention is suitable as various printing ink compositions, particularly as a heat-setting rotary press for sheet-fed offset printing presses and printing inks for sheet-fed printing.

Claims (5)

A printing ink composition comprising the composite particles (A) in a printing ink,
Solid polymer particles (A-1) composed of a resin, a wax or a mixture thereof which does not dissolve in the printing ink and the inorganic fine particles (A-) having an average particle diameter of 5 to 1000 nm adhered to the surface of the composite particles (A) 2), the volume average particle diameter of the composite particles (A) is in the range of 2 to 8 μm, and the volume content of particles exceeding 10 μm is 20% by volume or less, and the composite Printing ink composition characterized in that the sphericity of the particles (A) is 0.95 or more.   The composite particles (A) contain the inorganic fine particles (A-2) in an amount of 0.5 to 50 parts by mass with respect to 100 parts by mass of the solid polymer particles (A-1), and the inorganic particles (A) The printing ink composition according to claim 1, wherein the fine particles (A-2) are formed so as to adhere to the surface of the solid polymer particles (A-1).   The inorganic fine particle (A-2) is made of metal oxide, metal nitride, metal carbide, metal sulfate, sulfide and fluoride, or one or a mixture of these. Printing ink composition. The solid polymer particle (A-1) has a melting point of 120 ° C. or higher, and a needle with a load of 100 g according to JIS K-2235-5.4 is in the sample film at 25 ° C. for 5 seconds. The printing ink composition according to any one of claims 1 to 3, which is a wax having a penetration of 2.0 or less in which the depth of penetration into the unit is 10 ¹ mm.   The printing according to any one of claims 1 to 4, wherein the solid polymer particle (A-1) is an oxidized polyethylene wax having a melting point of 120 ° C or more and an acid value of 10 or more. Ink composition.

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