Inkjet ink composition, printed matter, and inkjet recording method

Abstract

To provide an ink composition for inkjet printing which gives a printing layer excellent in tactile, scratch resistance and adhesion to a base material, a printed matter and a recorded matter having an ink layer composed of the ink composition, and an inkjet recording method.SOLUTION: An ink composition contains the following components (A), (B) and (C), (A): 0.5-20 pts.mass in terms of solid content of a silicone acrylic copolymer resin emulsion, (B) 10-79.5 pts.mass in terms of a solid content of a urethane-based resin emulsion, and (C) 20-89.5 pts.mass of a pigment (total of solid contents of component (A) and component (B), and component (C) is 100 pts.mass), wherein the component (A) is an emulsion of a copolymerized matter of (a1) 60-99 pts.mass of polyorganosiloxane, and (a2) 1-40 pts.mass of an acrylate monomer and / or a methacrylate monomer (total of components (a1) and (a2) is 100 pts.mass).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an inkjet ink composition, printed matter , relates to an inkjet recording method. [Background technology]

[0002] Inkjet printing systems are printing systems that spray highly fluid liquid ink from minute nozzles onto a substrate to print. This system has recently become increasingly popular due to its ability to print high-resolution, high-quality images at high speed and with low noise using relatively inexpensive equipment.

[0003] It is expected that inkjet recording methods will be used in recording on recording media with low or no ink absorption in the future. In such applications, high levels of image color development and fastness (such as abrasion resistance, light resistance, ozone gas resistance, and water resistance) are required, and therefore inks using pigments as coloring materials are particularly useful.

[0004] Printed materials printed with pigment inks containing pigments as coloring materials tend to have localized pigment components on the surface of the recording medium, resulting in high color development. The pigments remain on the surface of the recording medium due to evaporation and penetration of vehicle components that occur during and after the ink is applied to the recording medium. However, because the pigments, which are coloring materials, tend to be present on the surface of the recording medium, the adhesion and abrasion resistance of the ink film are particularly important for pigment inks. To improve these properties of pigment ink printing, the addition of urethane resins to the inks has been investigated.

[0005] For example, Japanese Patent Application Laid-Open No. 2021-107527 uses a water-dispersed polyurethane resin in an aqueous inkjet ink. While it claims to provide an inkjet ink with excellent durability and processability, there are concerns that a urethane resin alone will not provide a smooth surface and will cause abrasion resistance.

[0006] Furthermore, Japanese Patent Application Laid-Open No. 2019-6936 discloses that dimethyl silicone is essential for urethane, which can provide rubbing resistance and washing resistance during printing. However, although dimethyl silicone has high initial water resistance, the dimethyl silicone on the surface volatilizes and is wiped off over time, so its performance cannot be said to be sufficient.

[0007] Furthermore, WO2017 / 104318 proposes that a powdered acrylic-modified polyorganosiloxane is incorporated into a photopolymerizable monomer to provide a liquid composition for inkjet printers with high abrasion resistance. However, because it is an acrylic, it is thought that adhesion is poor. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent Publication No. 2021-107527 [Patent Document 2] Japanese Patent Application Publication No. 2019-6936 [Patent Document 3] WO2017 / 104318 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention has been made in view of the above circumstances, and has an object to provide an ink composition for inkjet printing that provides a printed layer that is excellent in tactile feel, abrasion resistance, and adhesion to a substrate, a printed matter or recorded matter having an ink layer made of the ink composition, and an inkjet recording method. [Means for solving the problem]

[0010]

[0006] As a result of extensive research to achieve the above object, the present inventors have found that a layer obtained from an ink composition containing (A) a silicone-acrylic copolymer resin emulsion, (B) a urethane resin emulsion, and (C) a pigment in a specified ratio has excellent tactile feel, abrasion resistance, and adhesion to a substrate. In particular, the present invention provides a water-based ink composition for inkjet printing, and a printed material on which a film made of the water-based ink composition is formed.

[0011] That is, the present invention provides an ink composition containing the following components (A), (B), and (C): (A) silicone acrylic copolymer resin emulsion: 0.5 to 20 parts by mass in terms of solid content, (B) Urethane resin emulsion: 10 to 79.5 parts by mass in terms of solid content, (C) Pigment: 20~89.5 parts by mass (The total of the solid content of component (A), the solid content of component (B), and the solid content of component (C) is 100 parts by mass.) The component (A) (a1) 60 to 99 parts by mass of a polyorganosiloxane represented by the following general formula (1): (a2) an acrylic acid ester monomer and / or a methacrylic acid ester monomer: 1 to 40 parts by mass (the total of components (a1) and (a2) is 100 parts by mass), wherein the ink composition is an emulsion of a copolymer with the acrylic acid ester monomer and / or a methacrylic acid ester monomer: 1 to 40 parts by mass (the total of components (a1) and (a2) is 100 parts by mass). [ka] (In the formula, R 1 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms (however, R 2 and phenyl), R 2 are each independently an alkenyl group having 2 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms bonded to the carbon atoms are substituted with a mercapto group, a vinyl group, an acryloxy group, or a methacryloxy group, and R 3 are each independently a phenyl group or the above R 1 and at least one R3 is a phenyl group; X's are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group; a, b, c, and d are real numbers, such that, with respect to the sum of a, b, c, and d, a is a number that satisfies 0.11≦a / (a+b+c+d)<1, b is a number that satisfies 0.00001≦b / (a+b+c+d)≦0.05, c is a number that satisfies 0≦c / (a+b+c+d)≦0.6, and d is a number that satisfies 0.000001≦d / (a+b+c+d)≦0.24.

[0012] The present invention further provides an ink composition comprising the following components (A'), (B'), and (C), and water: (A') silicone acrylic copolymer resin: 0.1 to 20% by mass in the ink composition, (B') at least one resin selected from polyether polyurethane resins, polyester polyurethane resins, and polycarbonate polyurethane resins: 3 to 70% by mass in the ink composition; (C) Pigment: 0.1 to 25% by mass in the ink composition The component (A') (a1) 60 to 99 parts by mass of a polyorganosiloxane represented by the following general formula (1): The ink composition is characterized in that it is a copolymer with (a2) an acrylic acid ester monomer and / or a methacrylic acid ester monomer: 1 to 40 parts by mass (the total of the components (a1) and (a2) is 100 parts by mass). [ka] (In the formula, R 1 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms (however, R 2 and phenyl), R 2 are each independently an alkenyl group having 2 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms bonded to the carbon atoms are substituted with a mercapto group, a vinyl group, an acryloxy group, or a methacryloxy group, and R 3are each independently a phenyl group or the above R 1 and at least one R 3 is a phenyl group; X's are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group; a, b, c, and d are real numbers, such that, with respect to the sum of a, b, c, and d, a is a number that satisfies 0.11≦a / (a+b+c+d)<1, b is a number that satisfies 0.00001≦b / (a+b+c+d)≦0.05, c is a number that satisfies 0≦c / (a+b+c+d)≦0.6, and d is a number that satisfies 0.000001≦d / (a+b+c+d)≦0.24.

[0013] The present invention further provides a recorded or printed matter having a recording medium and a layer made of the ink composition adhered to the recording medium. In particular, the present invention provides a recorded or printed matter having a recording medium with low or no ink absorption. The present invention also provides a method for producing a printed matter, which includes the steps of ejecting the ink composition from an inkjet head and adhering the ink composition to a recording medium to perform printing. Furthermore, the present invention provides an inkjet recording method, which includes the steps of ejecting the ink composition of the present invention from an inkjet head and adhering the ink composition to a recording medium to perform printing. In the present invention, the term "recording medium" refers to a recording medium to which ink is attached, and means a printing medium or a material for printing. [Effects of the Invention]

[0014] The ink composition of the present invention provides printed matter and recorded matter having an ink layer that is excellent in tactile feel, abrasion resistance, and adhesion to a substrate. In particular, the ink composition of the present invention provides a printed layer that is excellent in coatability, adhesion, and fixability to a recording medium that has low ink absorption or no ink absorption, and is excellent in tactile feel, abrasion resistance, durability, etc. The ink composition of the present invention is useful as an ink composition for inkjet printing. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention provides an ink composition containing (A) a silicone acrylic copolymer resin emulsion, (B) a urethane resin emulsion, and (C) a pigment in a predetermined ratio. Each component will be described in detail below.

[0016] (A) Silicone acrylic copolymer resin emulsion Component (A) is an emulsion of a silicone acrylic copolymer resin, which is a copolymer of (a1) 60 to 99 parts by mass of a polyorganosiloxane represented by the following general formula (1) and (a2) 1 to 40 parts by mass of an acrylic acid ester monomer and / or a methacrylic acid ester monomer (the total of components (a1) and (a2) is 100 parts by mass). [ka] (In the formula, R 1 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms (however, R 2 and phenyl), R 2 are each independently an alkenyl group having 2 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms bonded to the carbon atoms are substituted with a mercapto group, a vinyl group, an acryloxy group, or a methacryloxy group, and R 3 are each independently a phenyl group or the above R 1 and at least one R 3 is a phenyl group, each X is independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group, a, b, c, and d are real numbers, and with respect to the sum of a, b, c, and d, a is a number that satisfies 0.11≦a / (a+b+c+d)<1, b is a number that satisfies 0.00001≦b / (a+b+c+d)≦0.05, c is a number that satisfies 0≦c / (a+b+c+d)≦0.6, and d is a number that satisfies 0.000001≦d / (a+b+c+d)≦0.24. More specifically, it is an emulsion of a silicone acrylic copolymer resin obtained by emulsion graft polymerization of (a1) a polyorganosiloxane represented by the above general formula (1) and (a2) an acrylic acid ester monomer and / or a methacrylic acid ester monomer.

[0017] The blending ratio of component (a1) to component (a2) is preferably 60 to 99 parts by mass and 1 to 40 parts by mass of component (a2) relative to 100 parts by mass of the total amount of component (a1) and component (a2), and more preferably 70 to 95 parts by mass and 5 to 30 parts by mass of component (a2). [ka]

[0018] R 1 are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 6 carbon atoms. Examples thereof include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl groups; cycloalkyl groups such as cyclopentyl, cyclohexyl, and cycloheptyl groups; aryl groups such as tolyl and naphthyl groups; alkenylaryl groups such as vinylphenyl groups; aralkyl groups such as benzyl, phenylethyl, and phenylpropyl groups; and alkenylaralkyl groups such as vinylbenzyl and vinylphenylpropyl groups; and groups in which some or all of the hydrogen atoms of these groups have been replaced with halogen atoms such as fluorine, bromine, and chlorine, carboxyl groups, alkoxy groups, alkenyloxy groups, and amino group Na Examples include those substituted with R 1 As the alkyl group, an unsubstituted alkyl group having 1 to 6 carbon atoms is preferred, and a methyl group is more preferred.

[0019] R 2are each independently an alkenyl group having 2 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms bonded to the carbon atoms have been substituted with a mercapto group, a vinyl group, an acryloxy group, or a methacryloxy group. Examples of the alkenyl group having 2 to 6 carbon atoms include a vinyl group and an allyl group. R 2 is preferably an alkyl group having 1 to 6 carbon atoms and having an acryloxy group or a methacryloxy group. The alkyl group is preferably a methyl group, an ethyl group, or a propyl group. 3 are each independently a phenyl group or the above R 1 and at least one R 3 is a phenyl group.

[0020] X's are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 6 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 4 carbon atoms, or a hydroxyl group. Examples of the unsubstituted or substituted monovalent hydrocarbon group having 1 to 20 carbon atoms include the above-mentioned R 1 Examples of the alkoxy group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a tetradecyloxy group. X is preferably a hydroxyl group, a methoxy group, an ethoxy group, a methyl group, or a butyl group.

[0021] a, b, c, and d are real numbers, and a is a number that satisfies 0.11≦a / (a+b+c+d)<1 (e.g., 0.999999 or less) with respect to the total number of a to d, and is preferably a number that satisfies 0.59≦a / (a+b+c+d)≦0.99998. b is a number that satisfies 0.00001≦b / (a+b+c+d)≦0.05 with respect to the total number of a to d, and is preferably a number that satisfies 0.00001≦b / (a+b+c+d)≦0.01. c is a number that satisfies 0≦c / (a+b+c+d)≦0.6 with respect to the total number of a to d, and is preferably a number that satisfies 0≦c / (a+b+c+d)≦0.30. d is a number that satisfies 0.000001≦d / (a+b+c+d)≦0.24 relative to the total number of a to d, and is preferably a number that satisfies 0.00001≦d / (a+b+c+d)≦0.1. If b exceeds 5% by mass, the tactile feel of the coating film will not be improved and the antifouling properties will also decrease. If d exceeds 24.0% by mass, the weight-average molecular weight will become small and the tactile feel will not be improved, which is not preferable. c is the number of siloxane units having a phenyl group. Having it within the above range is preferable in terms of transparency and heat resistance.

[0022] The weight-average molecular weight of (a1) polyorganosiloxane is 5,000 to 500,000, preferably 8,000 to 450,000, more preferably 100,000 to 450,000, and even more preferably 150,000 to 400,000. By having such a weight-average molecular weight, a coating agent can be obtained that imparts the good slip properties characteristic of silicone. Here, the molecular weight (M) of the polyorganosiloxane can be calculated from the specific viscosity ηsp (25° C.) of a toluene solution of the organopolysiloxane at a concentration of 1 g / 100 ml. ηsp=(η / η0)-1 (η0: viscosity of toluene η: viscosity of solution) ηsp=[η]+0.3[η] squared [η]=2.15×10 -4 M 0.65 Specifically, 20 g of emulsion was mixed with 20 g of IPA (isopropyl alcohol), the emulsion was broken, the IPA was discarded, and the remaining rubbery organopolysiloxane was dried at 105°C for 3 hours. This was made into a toluene solution of organopolysiloxane at a concentration of 1 g / 100 ml, and the viscosity was measured at 25°C using an Ubbelohde viscometer. The molecular weight (M) could be calculated by substituting the viscosity into the above formula (References: Nakamuta, Nikka, 77 858

[1956] , Doklady Akad. Nauk. USSR 89 65

[1953] ).

[0023] Such polyorganosiloxane (a1) is preferably used in the form of an emulsion, and may be a commercially available product or may be synthesized. When synthesized, it can be carried out by a known emulsion polymerization method, and can be easily synthesized by emulsifying and dispersing a cyclic organosiloxane or an α,ω-dihydroxysiloxane oligomer, an α,ω-dialkoxysiloxane oligomer, an alkoxysilane, or the like, which may have a fluorine atom, a (meth)acryloxy group, a carboxyl group, a hydroxyl group, or an amino group, and a silane coupling agent represented by the following general formula (2) in water using an anionic surfactant, and then adding a catalyst such as an acid as necessary to carry out a polymerization reaction. R 5 (4-e-f) R 6 f Si(OR 7 ) e (2) (In the formula, R 5 R represents a monovalent organic group having a polymerizable double bond, particularly an alkyl group having 1 to 6 carbon atoms substituted with an acryloxy group or a methacryloxy group. 6 is an alkyl group having 1 to 4 carbon atoms, R 7 represents an alkyl group having 1 to 4 carbon atoms, e represents an integer of 2 to 3, f represents an integer of 0 to 1, and e+f=2 to 3.

[0024] Examples of the cyclic organosiloxane include hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), 1,1-diethylhexamethylcyclotetrasiloxane, phenylheptamethylcyclotetrasiloxane, 1,1-diphenylhexamethylcyclotetrasiloxane, 1,3,5,7-tetravinyltetramethylcyclotetrasiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, 1,3,5,7-tetracyclohexyltetramethylcyclotetrasiloxane, tris(3,3,3-trifluoropropyl)trimethylcyclotrisiloxane, and 1,3,5,7-tetra(3-methacryloxypropyl)tetramethylcyclotetrasiloxane. Examples include 1,3,5,7-tetra(3-acryloxypropyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(3-carboxypropyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(3-vinyloxypropyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(p-vinylphenyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra[3-(p-vinylphenyl)propyl]tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(N-acryloyl-N-methyl-3-aminopropyl)tetramethylcyclotetrasiloxane, and 1,3,5,7-tetra(N,N-bis(lauroyl)-3-aminopropyl)tetramethylcyclotetrasiloxane. Octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane are preferably used.

[0025] Examples of silane coupling agents include acrylic silanes such as γ-(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropyltriethoxysilane, γ-(meth)acryloxypropyltripropoxysilane, γ-(meth)acryloxypropyltriisopropoxysilane, γ-(meth)acryloxypropyltributoxysilane, γ-(meth)acryloxypropylmethyldimethoxysilane, γ-(meth)acryloxypropylmethyldiethoxysilane, γ-(meth)acryloxypropylmethyldipropoxysilane, γ-(meth)acryloxypropylmethyldiisopropoxysilane, and γ-(meth)acryloxypropylmethyldibutoxysilane; and mercaptosilanes such as γ-mercaptopropylmethyldimethoxysilane and γ-mercaptopropyltrimethoxysilane. Alternatively, oligomers obtained by condensation polymerization of these may be more preferred because they suppress the generation of alcohol. Acrylic silanes are particularly preferred. Here, (meth)acryloxy refers to acryloxy or methacryloxy. These silane coupling agents are preferably used in an amount of 0.01 to 10 parts by mass, more preferably 0.01 to 5 parts by mass, per 100 parts by mass of the cyclic organosiloxane. If the amount is less than 0.01 part by mass, the transparency of the resulting coating agent may decrease, and if the amount is more than 10 parts by mass, the sliding properties may not be exhibited.

[0026] By copolymerizing the cyclic organosiloxane with the silane coupling agent, a polymerizable group (R 2 ) is introduced. This allows the (a2) (meth)acrylic acid ester monomer to be grafted onto the (a1) polyorganosiloxane.

[0027] As the polymerization catalyst used for the polymerization, a known polymerization catalyst may be used. Among them, a strong acid is preferred, and examples thereof include hydrochloric acid, sulfuric acid, dodecylbenzenesulfonic acid, citric acid, lactic acid, and ascorbic acid. Dodecylbenzenesulfonic acid, which has emulsifying ability, is preferred.

[0028] The amount of the acid catalyst used is preferably 0.01 to 10 parts by mass, and more preferably 0.2 to 2 parts by mass, per 100 parts by mass of the cyclic organosiloxane.

[0029] Examples of surfactants used in polymerization include anionic surfactants such as sodium lauryl sulfate, sodium laureth sulfate, N-acylamino acid salts, N-acyltaurate salts, aliphatic soaps, and alkyl phosphates, among which those that are easily soluble in water and do not have polyethylene oxide chains are preferred.More preferred are N-acylamino acid salts, N-acyltaurate salts, aliphatic soaps, and alkyl phosphates, and particularly preferred are sodium lauroyl methyl taurate, sodium myristoyl methyl taurate, and sodium lauryl sulfate.

[0030] The amount of the anionic surfactant used is preferably 0.1 to 20 parts by mass, and more preferably 0.5 to 10 parts by mass, per 100 parts by mass of the cyclic organosiloxane.

[0031] The polymerization temperature is preferably 50 to 75° C., and the polymerization time is preferably 10 hours or more, more preferably 15 hours or more. Furthermore, it is particularly preferable to age the mixture after polymerization at 5 to 30° C. for 10 hours or more.

[0032] (a2) The acrylic acid ester or methacrylic acid ester (hereinafter sometimes referred to as the acrylic component) is a linear or branched alkyl ester having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms, and more preferably 1 to 3 carbon atoms. It may have a functional group such as an amide group, a vinyl group, a carboxyl group, or a hydroxyl group. Examples of the acrylic acid ester and the methacrylic acid ester include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, and 2-ethylhexyl methacrylate. Only one of these may be used, or two or more may be copolymerized. Methyl acrylate, ethyl acrylate, methyl methacrylate, or ethyl methacrylate is preferred. The acrylic acid ester and the methacrylic acid ester preferably have a glass transition temperature (Tg) of 120°C or lower, preferably 110°C or lower. The lower limit is preferably -50°C. The component (a2) is adjusted and graft copolymerized so that the Tg of the resulting silicone acrylic copolymer resin is 0° C. or higher, preferably 5° C. or higher. When the silicone acrylic resin has the above Tg, a resin with excellent antifouling properties can be obtained.

[0033] The graft copolymerization of the (a1) polyorganosiloxane and the (a2) (meth)acrylic acid ester monomer may be carried out according to a conventionally known method, for example, using a radical initiator. The radical initiator is not particularly limited, but examples include persulfates such as potassium persulfate and ammonium persulfate, aqueous hydrogen persulfate, t-butyl hydroperoxide, and hydrogen peroxide. If necessary, a redox system using a reducing agent such as sodium sulfite, Rongalit, L-ascorbic acid, tartaric acid, sugars, or amines may also be used.

[0034] To improve emulsion stability, anionic surfactants such as sodium lauryl sulfate, sodium laureth sulfate, N-acylamino acid salts, N-acyltaurine salts, aliphatic soaps, and alkyl phosphates can be added. Nonionic emulsifiers such as polyoxyethylene lauryl ether and polyoxyethylene tridecyl ether can also be added.

[0035] Additionally, a chain transfer agent may be added to adjust the molecular weight.

[0036] The solid content of (A) silicone acrylic copolymer resin emulsion is preferably 35 to 50% by mass. The viscosity (25°C) is preferably 500 mPa·s or less, more preferably 20 to 300 mPa·s. The viscosity can be measured using a rotational viscometer. The emulsion preferably has an average primary particle size of 1000 nm or less, preferably 100 to 500 nm, and more preferably 150 to 350 nm. If the average primary particle size is too large, whitening occurs, while if it is too small, dispersibility decreases. The average primary particle size of the emulsified particles in the resin emulsion is the volume-based average particle size measured using a JEOL JEM-2100™.

[0037] The silicone acrylic copolymer resin emulsion of component (A) preferably has a solid content of component (A) of 0.5 to 20 parts by mass, more preferably 1.5 to 20 parts by mass, and even more preferably 2 to 15 parts by mass, relative to 100 parts by mass of the total solid content of components (A), (B), and (C). The glass transition temperature Tg of the silicone acrylic copolymer resin (A) is preferably 0°C or higher, more preferably 5°C or higher. The glass transition temperature (hereinafter sometimes referred to as Tg) can be measured using a flow tester after drying the emulsion.

[0038] An ink layer obtained from an ink composition for inkjet printing containing the above-mentioned (A) silicone-acrylic copolymer resin emulsion has excellent water resistance, humidity resistance, high gloss, and alcohol resistance. The amount of component (A) is preferably 0.1 to 20%, more preferably 0.4 to 18%, more preferably 0.5 to 15%, even more preferably 0.6 to 10%, and even more preferably 1.5 to 8%, in terms of solids content, based on 100% by mass of the ink composition of the present invention. If the solids content is less than the above-mentioned lower limit, the tactile feel, abrasion resistance, and stain resistance may not be fully exhibited, while if the solids content is more than the above-mentioned upper limit, the coating film surface may be easily stained.

[0039] (B) Urethane resin emulsion The (B) urethane resin emulsion may be synthesized by a known method, such as emulsion polymerization using an anionic or nonionic emulsifier, or may be a commercially available product. Examples of urethane resins include various water-soluble urethane resins, such as reaction products of polyisocyanate and polyol, in which the polyol is a polyether, polycarbonate, polyester, or other suitable polyol. The urethane resin emulsion is an emulsion of these urethane resins. To ensure that the urethane resin emulsion has film-forming ability, the particle size of the emulsified particles is preferably 10 to 500 nm. The viscosity (25°C) of the urethane resin used should preferably be 10 to 500 mPa·s. The glass transition temperature (Tg) of the urethane resin is preferably 120°C or lower, more preferably 60°C or lower, and even more preferably 30°C or lower. The lower limit of the glass transition temperature is preferably −50°C. The glass transition temperature can be measured according to JIS K7121.

[0040] Commercially available polyether-based urethane resin emulsions include Adeka Bontiter HUX-350 manufactured by Adeka Corporation, WLS-201 and WLS-202 manufactured by DIC Corporation, and Superflex E-4000 and E-4800 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. Examples of polycarbonate-based urethane resin emulsions include Hydran WLS-210 and WLS-213 manufactured by DIC Corporation, UW-1005E and UW-5502 manufactured by Ube Industries, Ltd., Permarin UA-368 manufactured by Sanyo Chemical Industries, Ltd., and Superflex 460 and Superflex 470 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. Examples of polyester-based urethane resin emulsions include Adeka Bontiter HUX-380 and HUX-540 manufactured by Adeka Corporation, and Superflex 420 and Superflex 860 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.

[0041] The average particle size of the emulsified particles of (B) urethane resin emulsion is more preferably 10 nm to 500 nm, even more preferably 20 nm to 350 nm, and even more preferably 20 nm to 150 nm. The average particle size is a volume-based average particle size measured using a JEM-2100™ manufactured by JEOL Ltd.

[0042] The amount of resin emulsion (B) blended is 10 to 79.5 parts by solids weight, preferably 20 to 79 parts by weight, and more preferably 25 to 75 parts by weight, per 100 parts by weight of the total solids weight of component (A), component (B), and component (C). The ink composition preferably contains 3 to 80% by weight, 3.5 to 70% by weight, preferably 4 to 30% by weight, and more preferably 4.5 to 15% by weight of resin emulsion (solids weight). If the resin emulsion (solids weight) is less than the lower limit, coating properties such as abrasion resistance may be significantly impaired. If the resin emulsion (solids weight) is greater than the upper limit, the coating feel may be poor.

[0043] (C) Pigment The (C) pigment may be any conventional pigment that is incorporated into ink compositions, and may be either an inorganic or organic pigment. Inorganic pigments include titanium oxide, red iron oxide (red iron oxide), yellow iron oxide, black iron oxide, Prussian blue, zinc oxide, cobalt blue, emerald green, viridian, titanium white, and carbon black. Organic pigments include alkali blue, lysol red, carmine 6B, disazo yellow, phthalocyanine blue, quinacridone red, and isoindoline yellow.

[0044] The pigments used in the present invention are shown by the color index as follows: Pigment White 4, Pigment White 6, Pigment White 21, Pigment Black 7 (carbon black), Pigment Blue 15, 15:1, 15:3, 15:4, 15:6, 60, Pigment Green 7 (chlorinated phthalocyanine green), 36 (brominated phthalocyanine green), Pigment Red 9, 48, 49, 52, 53, 57, 57:1, 97, 122, 149, 168, 177, 178, 179, 2 06, 207, 209, 242, 254, 255, Pigment Violet 19, 23, 29, 30, 37, 40, 50, Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 86, 93, 94, 95, 109, 110, 117, 120, 125, 128, 137, 138, 139, 147, 148, 150, 151, 154, 155, 166, 168, 180, 185, 213, Pigment Orange 36, 43, 51, 55, 59, 61, 71, 74, etc.

[0045] The average particle size of the pigment (C) is not particularly limited, but is preferably 5 nm to 10 μm, and more preferably 10 nm to 5 μm. The average particle size can be measured as a cumulative volume-based average value (or median diameter) in particle size distribution measurement by laser diffraction method.

[0046] The blending amount of the (C) pigment is 20 to 89.5 parts by mass, preferably 20 to 80 parts by mass, per 100 parts by mass of the total of the solid content of the (A) component, the solid content of the (B) component, and the (C) component. The content of the (C) pigment in the ink composition is 0.1 to 25% by mass, preferably 0.5 to 20% by mass, and more preferably 1 to 15% by mass. If the pigment is less than the lower limit, there is a problem of a lack of hiding power and an inability to change the design. If the pigment is more than the upper limit, there is a problem of poor dispersibility and the occurrence of lumps, etc., which is undesirable.

[0047] (D) Water-soluble organic solvent The ink composition of the present invention may further contain a water-soluble organic solvent. Examples of water-soluble organic solvents include ethylene glycol monoether, diethylene glycol monoether, propylene glycol monoether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, ethylene glycol, diethylene glycol, propylene glycol, glycerin, methanol, ethanol, isopropyl alcohol, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, acetone, ethyl acetate, diacetone alcohol, and 1,3-propanediol. These solvents may be used alone or in combination of two or more.

[0048] Preferably, the water-soluble organic solvent has 3 or more carbon atoms. Organic solvents with fewer than 3 carbon atoms may reduce the stability of the emulsion. More preferably, the organic solvent has 10 or fewer carbon atoms. Furthermore, the solubility parameter (sp value) of the water-soluble organic solvent is preferably 10 or more. Examples of organic solvents with an sp value of 10 or more and 3 or more carbon atoms include glycerin (SP value: 21.1), 1,3-propanediol (SP value: 13.5), diethylene glycol (SP value: 14.6), and propylene glycol (SP value: 14.8). There is no particular upper limit for the sp value, but it is usually 30 or less.

[0049] The total content (mass %) of the water-soluble organic solvent in the ink composition of the present invention is preferably 3 mass % or more and 70 mass % or less, more preferably 5 to 60 mass %, even more preferably 15 to 55 mass %, and still more preferably 25 to 50 mass %, based on the total mass of the inkjet ink composition.

[0050] The ink composition according to a preferred embodiment of the present invention is an aqueous ink composition containing water, which allows the polymer to be easily dispersed in an emulsion state, and makes it possible to easily form an image having excellent fixability and abrasion resistance by an inkjet method.

[0051] The water content is 10% by mass or more, preferably 15% by mass or more, and more preferably 20% by mass or more, relative to the total amount of the ink composition. The water in the ink composition includes, for example, water from the polymer particle dispersion liquid and pigment dispersion liquid used as raw materials, and added water. A water content of 10% by mass or more allows the ink composition to have a relatively low viscosity. The upper limit of the water content is preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 80% by mass or less, relative to the total amount of the ink composition.

[0052] The ink composition of the present invention can be obtained by mixing (A) an emulsion of a silicone acrylic copolymer resin, (B) an emulsion of a urethane resin, and (C) a pigment previously dispersed in water, an optional (D) organic solvent, and water by a known mixing and preparation method such as a propeller stirrer, a homogenizer, a ball mill, a bead mill, or a disper mixer.

[0053] For example, while component (B) is being stirred at 100 to 1000 rpm in a disperser mixer, component (A), an aqueous dispersion of component (C), and optional component (D) are added, and the mixture is stirred at 500 to 1500 rpm for 30 minutes to obtain a water-based ink composition.

[0054] The ink composition of the present invention may contain antioxidants, ultraviolet absorbers, antifreeze agents, pH adjusters, preservatives, antifoaming agents, antibacterial agents, antifungal agents, light stabilizers, antistatic agents, plasticizers, flame retardants, thickeners, surfactants, organic solvents such as film-forming aids, other resins, and the like, as long as the addition does not affect the ink composition's performance. The amount of these other components added is not particularly limited. For example, the amount of antifoaming agents and surfactants added to the ink composition is preferably 0.01 to 5%, more preferably 0.1 to 3%, based on the total mass of the ink composition.

[0055] The ink composition of the present invention is preferably used in an ink jet recording method. The recording medium is not particularly limited, but may be a low ink absorbent or non-ink absorbent recording medium. covered A recording medium having low ink absorption or non-ink absorption refers to a recording medium having the property of not absorbing ink at all or absorbing almost no ink. More specifically, in the present invention, a recording medium having low ink absorption or non-ink absorption is a recording medium having the property of not absorbing ink at all or absorbing almost no ink at all in the Bristow method. 1 / 2 Water absorption up to 10mL / m 2 The Bristow method is the most widely used method for measuring the amount of liquid absorbed in a short period of time, and is also adopted by the Japan Pulp and Paper Technical Association (JAPANTAPPI). Details of the test method are described in Standard No. 51 "Paper and Paperboard - Liquid Absorbency Test Method - Bristow Method" of the "JAPANTAPPI Paper and Pulp Test Methods 2000 Edition." Examples of recording media having low ink absorption or non-ink absorption properties include media that do not have an ink-absorbing ink-receiving layer on the recording surface, and media that have a coating layer with low ink absorption on the recording surface.

[0056] The non-ink-absorbing recording medium is not particularly limited, but examples thereof include substrates such as a plastic film having no ink-absorbing layer, a sheet in which a plastic is coated on a substrate such as paper, a sheet in which a plastic film is adhered to a substrate such as paper, etc. Examples of plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc.

[0057] The low ink-absorbent recording medium is not particularly limited, but examples thereof include substrates such as coated paper having a coating layer on the surface for receiving oil-based ink. Examples of coated paper include, but are not particularly limited to, printing paper such as art paper, coated paper, and matte paper.

[0058] By using the ink composition of the present invention, it is possible to covered It is also possible to more easily form a predetermined printed matter on a recording medium with good fixability and abrasion resistance.

[0059] In the inkjet recording method according to the present invention, covered It is more preferable that the recording medium is mainly composed of polyolefin (polyethylene, polypropylene, etc.) and polyethylene terephthalate (PET). covered Generally, it is difficult for ink to adhere to recording media. covered The ink composition of the present invention is particularly effective in forming a printed layer having excellent fixability and abrasion resistance on such a substrate. Therefore, the ink composition of the present invention is particularly preferably used for inkjet recording on a recording medium whose main component is polyolefin (polyethylene, polypropylene, etc.) and polyethylene terephthalate (PET).

[0060] According to the inkjet recording method of the present invention, for example, when the ink composition of the present invention is ejected from an inkjet head onto a recording medium to form a printed layer, it is possible to ensure intermittent ejection stability and obtain a printed matter that satisfies both the fixability and abrasion resistance of the printed matter.

[0061] The ink jet recording method of the present invention may be performed according to a conventionally known method. For example, the ink composition of the present invention is ejected from an ink jet recording head, covered This is a method of depositing the ink composition on a recording medium to record a printed matter. Methods for ejecting the ink composition include a method of applying mechanical energy to the ink composition using an electrostrictive element and a method of applying thermal energy to the ink composition. In the present invention, it is particularly preferable to use a method of applying mechanical energy to the ink composition using an electrostrictive element. The recording method is carried out using an inkjet recording apparatus equipped with the above-mentioned inkjet head. [Example]

[0062] The present invention will be specifically explained below with reference to Production Examples, Examples, and Comparative Examples, but the present invention is not limited to the following Examples. In the following Examples, parts and % represent parts by mass and % by mass, respectively. Each resin emulsion obtained in Production Examples and Comparative Production Examples was measured as follows.

[0063] <Average particle size> Measurement was performed using a JEM-2100TM manufactured by JEOL.

[0064] <Glass transition temperature Tg> The glass transition temperature Tg was measured for approximately 1 g of silicone acrylic copolymer resin powdered by spray drying using a Shimadzu flow tester under a load of 5 kgf at a temperature increase rate of 5° C. per minute.

[0065] <Solid content (resin content)> Approximately 1 g of each emulsion (sample) was accurately weighed onto an aluminum foil dish, placed in a dryer maintained at 105-110°C, heated for 1 hour, then removed from the dryer and allowed to cool in a desiccator. The dried sample was weighed and the evaporation residue (i.e., solid content) was calculated using the following formula.

number

[0066] (A) Example of Production of Silicone Acrylic Copolymer Resin Emulsion [Manufacturing Example 1] A solution of 600g of octamethylcyclotetrasiloxane, 0.48g of γ-methacryloxypropylmethyldiethoxysilane, 6g of sodium lauryl sulfate dissolved in 54g of purified water, and a solution of 6g of dodecylbenzenesulfonic acid dissolved in 54g of purified water were placed in a 2L polyethylene beaker and emulsified uniformly using a homomixer. Then, 470g of water was gradually added to dilute the mixture. The pressure was 300kgf / cm. 2 The emulsion was passed through a high-pressure homogenizer twice at 100°C to obtain a uniform white emulsion. The emulsion was transferred to a 2 L glass flask equipped with a stirrer, thermometer, and reflux condenser, and subjected to a polymerization reaction at 55°C for 24 hours. After aging at 15°C for 24 hours, the emulsion was neutralized to near neutrality with 12 g of a 10% aqueous sodium carbonate solution. The structure of the polyorganosiloxane obtained by the above polymerization reaction is 1 H-NMR and 29 Si-NMR (equipment name: JNM-ECA600, measurement solvent: CDCl 3、 When confirmed by 1H frequency 600 MHz, room temperature, accumulation number 128 times 29Si frequency 600 MHz, room temperature, accumulation number 5000 times), it was expressed by the following formula (1-1), and Mw (weight average molecular weight, measurement method as above) was 250,000. [ka] In formula (1-1), R 2 is a γ-methacryloxypropyl group, and X is a hydroxyl group or an ethoxy group. The ratios of a, b, and d are shown in Table 1. To the neutralized reaction solution (containing 534 g of the polyorganosiloxane obtained above), 232 g of methyl methacrylate (MMA) was added dropwise over 3 to 5 hours while carrying out a redox reaction between the peroxide and the reducing agent at 30°C, resulting in copolymerization of the polyorganosiloxane with acrylic, yielding a silicone acrylic copolymer resin emulsion with a non-volatile content of 45.2%. The average particle size and solids content of the silicone acrylic copolymer resin emulsion are shown in Table 2.

[0067] [Manufacturing Example 2] 600g of octamethylcyclotetrasiloxane, 0.60g of gamma-methacryloxypropylmethyldiethoxysilane, 6g of sodium lauryl sulfate dissolved in 54g of pure water, and 6g of dodecylbenzenesulfonic acid dissolved in 54g of pure water were placed in a 2L polyethylene beaker and emulsified uniformly using a homomixer. After that, 470g of water was gradually added to dilute the mixture, and the mixture was heated under a pressure of 300kgf / cm. 2 The emulsion was passed through a high-pressure homogenizer twice at 100°C to obtain a uniform white emulsion. The emulsion was transferred to a 2 L glass flask equipped with a stirrer, a thermometer, and a reflux condenser, and subjected to a polymerization reaction at 55°C for 24 hours. After aging at 5°C for 24 hours, the emulsion was neutralized to near neutrality with 12 g of a 10% aqueous sodium carbonate solution. The structure of the polyorganosiloxane obtained by the above polymerization reaction was determined by NMR (instrument name: JNM-ECA600, measurement solvent: CDCl 3、 The measurement conditions were the same as in Production Example 1, and the polymer was found to be represented by the above formula (1-1), with Mw (weight average molecular weight, measured by the above method) being 400,000. 2 is a γ-methacryloxypropyl group, and X is a hydroxyl group or an ethoxy group. The ratios of a, b, and d are shown in Table 1. To the neutralized reaction solution (containing 534 g of the polyorganosiloxane obtained above), 61 g of methyl methacrylate (MMA) was added dropwise over 3 to 5 hours while carrying out a redox reaction between the peroxide and the reducing agent at 30°C, resulting in copolymerization of the polyorganosiloxane with acrylic, yielding a silicone acrylic copolymer resin emulsion with a non-volatile content of 44.8%. The average particle size and solids content of the silicone acrylic copolymer resin emulsion are shown in Table 2.

[0068] [Manufacturing Example 3] A solution of 300 g of octamethylcyclotetrasiloxane, 300 g of diphenyldimethylsiloxane (KF-54 manufactured by Shin-Etsu Chemical Co., Ltd.), 0.96 g of γ-methacryloxypropylmethyldiethoxysilane, 24 g of 50% sodium alkyldiphenylether disulfonate (Pelex SS-L manufactured by Kao Corporation) in 45 g of purified water, and a solution of 6 g of dodecylbenzenesulfonic acid in 54 g of purified water were placed in a 2 L polyethylene beaker and emulsified uniformly using a homomixer. After that, 490 g of water was gradually added to dilute the mixture, and the mixture was heated under a pressure of 300 kgf / cm. 2 The emulsion was passed through a high-pressure homogenizer twice at 55°C to obtain a uniform white emulsion. The emulsion was transferred to a 2 L glass flask equipped with a stirrer, thermometer, and reflux condenser, and subjected to a polymerization reaction at 55°C for 10 to 20 hours. After aging at 10°C for 10 to 20 hours, the emulsion was neutralized to a near-neutral pH with 12 g of a 10% aqueous sodium carbonate solution. The structure of the polyorganosiloxane obtained by the above polymerization reaction was determined by NMR (instrument name: JNM-ECA600, measurement solvent: CDCl 3、 When confirmed under the same measurement conditions as in Production Example 1, it was found to be represented by the following formula (1-2) and had Mw (weight average molecular weight, measured by the method described above) of 8,000. [ka] In the above formula (1-2), R 2 is a γ-methacryloxypropyl group, and R 3 ' and R 3 '' is a phenyl group or a methyl group, and R 3 ' and R 3At least one of a, b, c, and d is a phenyl group, and X is a hydroxyl or ethoxy group. The ratios of a, b, c, and d are shown in Table 1. The emulsion obtained after the neutralization had a non-volatile content (solids content) of 47.5% after drying at 105°C for 3 hours. 242g of methyl methacrylate (MMA) was added dropwise to the neutralized reaction solution (containing 534g of the polyorganosiloxane obtained above) over 3-5 hours while carrying out a redox reaction with peroxide and a reducing agent at 30°C to copolymerize the polyorganosiloxane with acrylic, yielding a silicone-acrylic copolymer resin emulsion with a non-volatile content of 45.5%. The average particle size and solids content of the silicone-acrylic copolymer resin emulsion are shown in Table 2.

[0069] [Manufacturing Example 4] A uniform white emulsion was obtained by repeating the above-mentioned Preparation Example 1. As in Preparation Example 1, the emulsion was transferred to a 2 L glass flask equipped with a stirrer, thermometer, and reflux condenser, and polymerization reaction was carried out at 55°C for 24 hours. The emulsion was then aged at 15°C for 24 hours and neutralized to near neutrality with 12 g of 10% aqueous sodium carbonate solution. The resulting polyorganosiloxane was represented by the above-mentioned formula (1-1) and had an Mw (weight-average molecular weight, measured as described above) of 250,000. To the neutralized reaction solution (containing 534 g of the polyorganosiloxane obtained above), 162 g of methyl methacrylate (MMA) and 80 g of butyl acrylate (BA) were added dropwise over 3 to 5 hours, while a redox reaction was carried out with a peroxide and a reducing agent at 30°C to copolymerize the acrylic into silicone, yielding a silicone-acrylic copolymer resin emulsion with a nonvolatile content of 44.9%. The average particle size and solid content of the silicone acrylic copolymer resin emulsion are shown in Table 2.

[0070] [Comparative Manufacturing Example 1] A uniform white emulsion was obtained by repeating the above Production Example 1. As in Production Example 1, the emulsion was transferred to a 2 L glass flask equipped with a stirrer, thermometer, and reflux condenser, and subjected to a polymerization reaction at 55°C for 24 hours. After aging at 15°C for 24 hours, the emulsion was neutralized to near neutrality with 12 g of a 10% aqueous sodium carbonate solution. The resulting polyorganosiloxane was represented by the above formula (1-1) and had an Mw (weight average molecular weight, measured as described above) of 250,000. To the neutralized reaction solution (containing 534 g of the polyorganosiloxane obtained above), 541 g of methyl methacrylate (MMA) was added dropwise over 3 to 5 hours while carrying out a redox reaction with peroxide and a reducing agent at 30°C, resulting in copolymerization of the polyorganosiloxane with acrylic, yielding a silicone acrylic copolymer resin emulsion with a non-volatile content of 45.5%. The average particle size and solids content of the silicone acrylic copolymer resin emulsion are shown in Table 2.

[0071] [Comparative Manufacturing Example 2] A uniform white emulsion was obtained by repeating the above-mentioned Production Example 1. As in Production Example 1, the emulsion was transferred to a 2 L glass flask equipped with a stirrer, thermometer, and reflux condenser, and subjected to a polymerization reaction at 55°C for 24 hours. After aging at 15°C for 24 hours, the emulsion was neutralized to near neutrality with 12 g of a 10% aqueous sodium carbonate solution. The resulting polyorganosiloxane was represented by the above formula (1-1) and had an Mw (weight average molecular weight, measured as above) of 250,000. The acrylic was not polymerized, and the reaction was terminated as is. A silicone resin emulsion with a nonvolatile content of 44.8% was obtained.

[0072] [Comparative Manufacturing Example 3] 552g of octamethylcyclotetrasiloxane, 48g of gamma-methacryloxypropylmethyldiethoxysilane, 6g of sodium lauryl sulfate dissolved in 54g of pure water, and 6g of dodecylbenzenesulfonic acid dissolved in 54g of pure water were placed in a 2L polyethylene beaker and emulsified uniformly using a homomixer. After that, 470g of water was gradually added to dilute the mixture, and the mixture was heated under a pressure of 300kgf / cm. 2The emulsion was passed through a high-pressure homogenizer twice at 100°C to obtain a uniform white emulsion. The emulsion was transferred to a 2 L glass flask equipped with a stirrer, a thermometer, and a reflux condenser, and subjected to a polymerization reaction at 55°C for 24 hours. After aging at 15°C for 24 hours, the emulsion was neutralized to near neutrality with 12 g of a 10% aqueous sodium carbonate solution. The structure of the polyorganosiloxane obtained by the above polymerization reaction was determined by NMR (instrument name: JNM-ECA600, measurement solvent: CDC1 3、 When confirmed under the same measurement conditions as in Production Example 1, it was found to be represented by the following formula (1-3) and had Mw (weight average molecular weight: measured by GPC) of 250,000. [ka] In formula (1-3), R 2 is a γ-methacryloxypropyl group, and X is a hydroxyl group or an ethoxy group. The ratios of a, b, and d are shown in Table 1. To the neutralized reaction solution (containing 534 g of the polyorganosiloxane obtained above), 232 g of methyl methacrylate (MMA) was added dropwise over 3 to 5 hours while carrying out a redox reaction with peroxide and a reducing agent at 30°C, resulting in acrylic copolymerization with the polyorganosiloxane, yielding a silicone acrylic copolymer resin emulsion with a nonvolatile content of 45.0%. The average particle size and solids content of the silicone acrylic copolymer resin emulsion are shown in Table 2.

[0073] [Table 1] D4: Octamethylcyclotetrasiloxane KF-54: Diphenyldimethylsiloxane PELLEX SS-L: 50% Sodium Alkyl Diphenyl Ether Disulfonate

[0074] [Table 2]

[0075] [Examples 1 to 8, Comparative Examples 1 to 6] Components (A) to (D) and an antifoaming agent were mixed according to the formulations shown in Tables 3 and 5 below, and stirred with a propeller stirrer to obtain ink compositions. [Ink preparation] For example, in Example 1, 1.5 parts of silicone acrylic copolymer resin emulsion (45% solids), 13.5 parts of urethane resin emulsion WLS-213 (35% solids), 5 parts of carbon black MA100 (manufactured by Mitsubishi Paper Mills), 1.5 parts of Noigen XL-400D, 15 parts of glycerin, 12 parts of 1,3-propanediol, 10 parts of diethylene glycol, and 5 parts of propylene glycol were added and mixed at 500 rpm, followed by the addition of 36.5 parts of water. The mixture was stirred at 1000 rpm for 60 minutes in a paint shaker (manufactured by Asada Iron Works), and then the YTZ ball was removed to prepare the ink.

[0076] Tables 4 and 6 show the solid content of component (A), the solid content of component (B), and the amount of component (C) per 100 parts by mass of the total of the solid contents of components (A) and (B) and the amount of component (C).

[0077] The urethane resin emulsions (B) used in the following examples and comparative examples are as follows: Hydran WLS-213 (DIC polycarbonate polyurethane dispersion) solid content 35%, particle size 20-30nm Hydran WLS-201 (DIC polyether polyurethane dispersion) solid content 35%, particle size 20-30nm Adeka Bontiter HUX-380 (Adeka Corporation polyester polyurethane dispersion) solid content 40%, particle size 0.2 μm

[0078] (C) Pigment Carbon black MA100 (Mitsubishi Paper Mills, particle size 24 nm)

[0079] The component (D) used in the following examples and comparative examples is as follows: Glycerin (SP value: 21.1) 1,3-propanediol (SP value: 13.5) Diethylene glycol (SP value: 14.6) Propylene glycol (SP value: 14.8)

[0080] [Film forming method] Each ink composition was applied to a PET film using a bar coater so that the dry film thickness was 26 μm, and then the film was left at room temperature for 2 days before measurement.

[0081] <Tactile sensation, static and dynamic friction coefficient measurement Set> Using a HEIDON TYPE-38 (manufactured by Shinto Scientific Co., Ltd.), a 200 g metal indenter was brought into contact with the coating film perpendicularly and moved at a speed of 3 cm / min. The frictional force was measured, and the static and dynamic friction coefficients were calculated from the frictional force. The tactile feel was evaluated as "good" when the static friction coefficient was less than 0.10, the dynamic friction coefficient was less than 0.07, and the difference between the static and dynamic friction coefficients was less than 0.05.

[0082] <Dispersibility (Stability over time)> Each ink composition was left to stand at room temperature for one week, and sedimentation over time was visually evaluated according to the following criteria. ○: No sedimentation △: Settled but can be stirred again ×: Settled and not restored

[0083] <Coatability> Each ink composition was applied to a non-ink-absorbent soft vinyl chloride film, Super Film Non-Tack E (manufactured by Okamoto Corporation), with a thickness of 9 μm (dry weight solid content 3.6 g / m) using a bar coater No. 4. 2 ) and dried at 40°C for 30 seconds to form an ink layer. The appearance of the ink layer was visually observed and evaluated according to the following criteria. ○: No defects on the coated surface △: There are some defects in appearance such as small bumps on the coated surface ×: There are many defects in appearance such as bumps on the coated surface

[0084] <Adhesion> After affixing cellophane tape (manufactured by Nichiban Co., Ltd., registered trademark) to the ink layer of the coated product obtained in the above coating test, The above-mentioned Cellotape (registered trademark) The film was peeled off and evaluated according to the following criteria. ○: Ink layer No peeling △: Ink layer Some peeling ×: The ink layer Complete peeling did

[0085] <Color tone> Each ink composition was applied to a commercially available paper using a bar coater No. 4 to a thickness of 9 μm (dry weight solid content 3.6 g / m 2 ) and dried at 40°C for 30 seconds to form an ink layer (printed layer). The appearance of the resulting coated paper and ink layer was visually observed and evaluated according to the following criteria. ○: Coated paper and ink layer The color tone is the same △: Black density is insufficient ×: Color tone has changed

[0086] <Ink absorbency (water resistance)> The paper (printed matter) obtained in the above color tone test was placed in a Gakushin-type dye rub fastness tester (manufactured by Yasuda Seiki Seisakusho). The printed surface was rubbed 25 times with gauze moistened with water. After rubbing, the printed surface and gauze were visually observed and evaluated according to the following criteria. ○: No color transfer to gauze △: Color transfer is observed ×: The color has completely transferred and the color of the printed surface has faded

[0087] <Ink absorbency (humidity resistance)> The paper (printed matter) obtained in the above color tone test was left to stand for one day at 50° C. and 90% humidity. After standing, the printed surface was visually observed and evaluated according to the following criteria. ○: No bleeding in the printed area △: Slight bleeding is observed from the printed area. ×: Completely blurred

[0088] [Table 3]

[0089] [Table 4]

[0090] [Table 5]

[0091] [Table 6]

[0092] As shown in Table 5 above, the printed layers obtained from the ink compositions of Comparative Examples 1, 3, and 4, which do not contain the silicone acrylic copolymer resin emulsion of the present invention, are poor in tactile feel, abrasion resistance, and adhesion to the substrate. Furthermore, the ink composition of Comparative Example 2 is poor in dispersibility and coatability, and the resulting printed film is poor in adhesion to the substrate. The ink compositions of Comparative Examples 5 and 6 are poor in dispersibility, and no printed matter with good tactile feel, abrasion resistance, adhesion, and color development is obtained. In contrast, as shown in Table 3 above, the ink composition of the present invention is excellent in dispersibility, coatability, and adhesion to the substrate, and the resulting printed film is excellent in tactile feel, abrasion resistance, adhesion to the substrate, and durability. The ink composition of the present invention is useful as an aqueous ink composition for inkjet printing.

Claims

1. An ink composition containing the following components (A), (B), and (C): (A) Silicone acrylic copolymer resin emulsion: 0.5 to 20 parts by mass in terms of solid content, (B) Urethane resin emulsion: 10 to 79.5 parts by mass in terms of solid content, (C) Pigment: 20 to 89.5 parts by mass (However, the total of the solid content of component (A), the solid content of component (B), and the solid content of component (C) is 100 parts by mass.) The component (A) (a1) 60 to 99 parts by mass of a polyorganosiloxane represented by the following general formula (1): the ink composition, characterized in that it is an emulsion of a copolymer with (a2) an acrylic acid ester monomer and / or a methacrylic acid ester monomer: 1 to 40 parts by mass (the total of components (a1) and (a2) is 100 parts by mass). 【Chemistry 1】 (In the formula, R １ are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms (provided that R ２ and phenyl group), R ２ are each independently an alkenyl group having 2 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms bonded to the carbon atoms are substituted with a mercapto group, a vinyl group, an acryloxy group, or a methacryloxy group, and R ３ are each independently a phenyl group or the above R １ and at least one R ３ is a phenyl group; X's are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group; a, b, c, and d are real numbers, and with respect to the sum of a, b, c, and d, a is a number that satisfies 0.11≦a / (a+b+c+d)<1, b is a number that satisfies 0.00001≦b / (a+b+c+d)≦0.05, c is a number that satisfies 0≦c / (a+b+c+d)≦0.6, and d is a number that satisfies 0.000001≦d / (a+b+c+d)≦0.

24.

2. 2. The ink composition according to claim 1, wherein the component (B) is an emulsion of at least one resin selected from the group consisting of polyether polyurethane resins, polyester polyurethane resins, and polycarbonate polyurethane resins.

3. 2. The ink composition according to claim 1, wherein the emulsion of the silicone acrylic copolymer resin (A) has an average primary particle size of emulsified particles of 1000 nm or less.

4. 2. The ink composition according to claim 1, wherein the pigment (C) has an average particle size of 5 nm to 10 μm.

5. 2. The ink composition according to claim 1, wherein the amount of component (A) in the ink composition is 0.1 to 20% by mass in terms of solid content, the amount of component (B) in the ink composition is 3 to 70% by mass in terms of solid content, and the amount of component (C) in the ink composition is 0.1 to 25% by mass.

6. The ink composition according to claim 1, further comprising (D) a water-soluble organic solvent in an amount of 3% by mass to 70% by mass relative to the total mass of the ink composition.

7. 7. The ink composition according to claim 6, wherein component (D) is an organic solvent having a solubility parameter (SP value) of 10 or more and having 3 or more carbon atoms.

8. The ink composition according to claim 1, which contains water in an amount of 10% by mass or more based on the total mass of the ink composition.

9. An ink composition comprising the following components (A'), (B'), and (C), and water: (A') silicone acrylic copolymer resin: 0.1 to 20% by mass in the ink composition; (B') at least one resin selected from polyether polyurethane resins, polyester polyurethane resins, and polycarbonate polyurethane resins: 3 to 70% by mass in the ink composition; (C) Pigment: 0.1 to 25% by mass in the ink composition The component (A') (a1) 60 to 99 parts by mass of a polyorganosiloxane represented by the following general formula (1): (a2) an acrylic acid ester monomer and / or a methacrylic acid ester monomer: 1 to 40 parts by mass (the total of components (a1) and (a2) is 100 parts by mass), 【Chemistry 2】 (In the formula, R １ are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms (provided that R ２ and phenyl group), R ２ are each independently an alkenyl group having 2 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms bonded to the carbon atoms are substituted with a mercapto group, a vinyl group, an acryloxy group, or a methacryloxy group, and R ３ are each independently a phenyl group or the above R １ and at least one R ３ is a phenyl group; X's are each independently a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group; a, b, c, and d are real numbers, and with respect to the sum of a, b, c, and d, a is a number that satisfies 0.11≦a / (a+b+c+d)<1, b is a number that satisfies 0.00001≦b / (a+b+c+d)≦0.05, c is a number that satisfies 0≦c / (a+b+c+d)≦0.6, and d is a number that satisfies 0.000001≦d / (a+b+c+d)≦0.

24.

10. The ink composition according to claim 9, further comprising (D) a water-soluble organic solvent in an amount of 3% by mass to 70% by mass relative to the total mass of the ink composition.

11. The ink composition according to claim 10, wherein the component (D) is an organic solvent having a solubility parameter (SP value) of 10 or more and having 3 or more carbon atoms.

12. 12. The ink composition according to claim 1, wherein the difference between the static friction coefficient and the dynamic friction coefficient of a film made of the ink composition is less than 0.

05.

13. An ink for ink-jet printing, comprising the ink composition according to any one of claims 1 to 11.

14. A printed matter comprising a recording medium and the ink composition according to any one of claims 1 to 11 adhered to the recording medium.

15. The printed matter according to claim 14, wherein the recording medium has low ink absorption or no ink absorption.

16. A method for producing a printed matter according to claim 14, comprising the steps of ejecting the ink composition according to any one of claims 1 to 11 from an inkjet head and depositing the ink composition on a recording medium to obtain the printed matter according to claim 14.

17. An inkjet recording method comprising the steps of ejecting the ink composition according to any one of claims 1 to 11 from an inkjet head and depositing the ink composition on a recording medium to perform printing.

18. 18. The ink jet recording method according to claim 17, wherein the recording medium has low ink absorption or no ink absorption.

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