JP2017025289A - Active energy ray-curable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active energy ray-curable composition excellent in inkjet discharge stability even when an ink generates volatilization thickening on a nozzle pore surface of a head.SOLUTION: There is provided an active energy ray-curable composition containing a polymerizable monomer, a polymer component, a polymer dispersion and a pigment and having yield value of the active energy ray-curable composition and yield value when the active energy ray-curable composition is dried to become 70 mass% of initial weight of 0.1 Pa or less respectively.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an active energy ray curable composition, an active energy ray curable ink, a material for three-dimensional modeling, an active energy ray curable composition container, an image forming apparatus, an image forming method, a cured product, and a molded product.

Ink-jet inks often require pigment-based inks because pigments are superior to dyes in terms of various durability. However, unlike a dye that dissolves uniformly in ink, the pigment does not dissolve uniformly in the ink, so it is necessary to disperse the pigment in the ink as uniformly as possible.
In sufficiently low-viscosity pigment-based inks, even if the dispersion state of the pigment in the ink is somewhat bad, it usually does not show a large yield value, but in high-viscosity pigment-based inks having a certain viscosity or higher, temporarily When the dispersion state of the pigment in the ink is not good and is easy to aggregate, the ink exhibits a remarkable structural viscosity and the yield value becomes large.
Under such conditions, it is difficult to eject an ink in a stationary state (without fluidity) in an initial state (a state in which no shear stress is applied) with a general ink jet ejection head.
In order to stably eject the stationary ink, it is necessary to apply a considerable shear stress to the ink to cause the ink to flow, and the yield value of the ink must be smaller than the shear stress that can be applied by the inkjet ejection head. I must.

Japanese Patent Application Laid-Open No. 2002-265848 discloses a toner having a yield value of 5 to 100 Pa at a liquid temperature of 25 ° C. in which a colorant and a colorant containing a colorant are atomized by a shock wave and uniformly dispersed in an organic solvent. Certain colorant dispersions are disclosed.
JP-A-2009-258619 of Patent Document 2 discloses (A) a colorant, (B) a polyfunctional monomer, (C) a binder resin, ( D) A pigment dispersion containing an surfactant having an HLB value of 10 or less and (E) an organic solvent and having a yield value of 200 mPa or less forms a pixel having excellent flatness and no unpainted portion. It states that it can be done.
Further, JP 2008-101099 A of Patent Document 3 contains at least an organic solvent and a polymer compound, and at 25 ° C. by a measurement method performed with an increase in shear rate using a rotary viscometer. When the viscosity measured at a shear rate of 1 × 10 ³ sec ⁻¹ is A and the viscosity measured at a shear rate of 1 × 10 ⁴ sec ⁻¹ is B, the viscosity B is 1 to 30 mPa · s, and the thixotropic coefficient A / It is disclosed that an oil-based pigment ink composition having B of 1.01-1.40 can improve ejection stability during high-speed printing at a driving frequency of 10 KHz or higher.
Japanese Patent Application Laid-Open No. 2004-18264 of Patent Document 4 includes a resin acid metal salt and an essential oil in at least a non-aqueous solvent, a shear viscosity of 10 mPa · s or less, and a yield value of 200 mPa or less. It has been disclosed that an inkjet recording liquid is excellent in ejection stability, fixability to non-paper-based recording materials such as ceramics, glass, ceramics, and metals, and color developability.

These inks contain an organic solvent, and the addition of the organic solvent makes it easy to reduce the viscosity of the ink.
However, in recent years, from the viewpoint of environmental protection, it has been desired not to release VOC (volatile organic solvent) to the atmosphere. Furthermore, characteristics such as quick-drying and toughness of the coating film, which are not found in existing ink-jet inks. The photopolymerizable inkjet ink possessed is widely studied mainly for industrial use.
From this point of view, Japanese Patent Application Laid-Open No. 2013-112691 of Patent Document 5 discloses a photopolymerizable ink that does not contain an organic solvent and has excellent discharge stability when the yield value of the ink is 0.2 Pa or less.
However, some photopolymerizable monomers contained in the ink are likely to volatilize depending on the usage environment after being left without the cap of the ejection head, and the viscosity of the ink on the nozzle surface may increase. In this case, when the yield value is 0.2 Pa or less, there is a problem in the ejection at the front end of the image, and the ejection is not recovered in the predetermined idle ejection before the image portion is ejected.

On the other hand, in order to obtain good curability, a photopolymerizable inkjet ink substantially free of an organic solvent needs to use a monomer having a relatively large molecular weight such as a polyfunctional monomer, and has a sufficiently low viscosity. It adjusts so that it can discharge as an inkjet ink in combination with a different monomer.
Many of the monomers used in conventional photopolymerizable ink-jet inks are toxic, especially low-cost and easily procurable (meth) acrylic acid esters with sufficiently low viscosity that are allergic to the skin. Most of the skin sensitizers that cause toxicities are highly toxic. At present, even if such ink is used, it can be seen that it is operated by wearing protective equipment, but it is desirable that there is no problem in skin sensitization, and it can be discharged at room temperature even if a polymer component is blended. Although it is required to obtain a photopolymerizable inkjet ink having a sufficiently low viscosity, many of such low-viscosity and low-toxic monomers have a high vapor pressure, and the above-mentioned volatile thickening occurs on the nozzle surface. In some cases, a leading edge image may be lost, and the prior art does not show a solution for this problem.

  Therefore, an object of the present invention is to provide an active energy ray-curable composition that is excellent in inkjet discharge stability even when the ink volatilizes and thickens on the nozzle hole surface of the head.

  In order to solve the above problems, the active energy ray-curable composition of the present invention is a non-aqueous active energy ray-curable composition containing a polymerizable monomer, a polymer component, a polymer dispersant, and a pigment. Both the yield value of the active energy ray-curable composition and the yield value when the active energy ray-curable composition is dried to 70 mass% of the initial weight are 0.1 Pa or less. It is characterized by that.

  ADVANTAGE OF THE INVENTION According to this invention, even if ink raise | generates volatile thickening on the nozzle hole surface of a head, the active energy ray hardening-type composition which is excellent in inkjet discharge stability can be provided.

1 is a schematic diagram illustrating an example of an image forming apparatus according to the present invention. It is the schematic which shows an example of another image forming apparatus used by this invention. It is the schematic which shows an example of another image forming apparatus used by this invention. It is the schematic which shows an example of the ink bag of an ink cartridge containing an ink. FIG. 5 is a schematic view showing an example of an ink cartridge containing ink including the ink bag of FIG. 4. It is a figure which shows the relationship between the polymer dispersant adsorption amount of the carbon black in the Example of this invention, and the compounding ratio of a polymer dispersant.

Hereinafter, the present invention will be described in detail.
(Active energy ray-curable composition)

The active energy ray-curable composition of the present invention includes at least a polymerizable monomer, a polymer component, a polymer dispersant, and a pigment. The polymer dispersant is preferably contained in an amount more than that which is saturatedly adsorbed on the pigment and does not substantially contain a volatile organic solvent. By containing more than the amount that is saturatedly adsorbed to the pigment as the polymer dispersant, the adsorbed dispersant becomes difficult to desorb, so the dispersibility of the pigment, that is, the repulsive force between the particles is improved, and the pigment particles The interaction to be agglomerated is weakened and the flow can be started with a minute shear stress.
Here, “substantially free of volatile organic solvent” means that a volatile organic solvent is not used as a material of the active energy ray-curable composition, and other dispersants such as a polymer dispersant and a polymerizable monomer are used. It does not mean that volatile organic solvents derived from materials are not included.
The active energy ray-curable composition of the present invention is preferably used as an active energy ray-curable ink, and in particular, an inkjet ink is preferred. Hereinafter, an active energy ray-curable ink (hereinafter sometimes referred to as ink) will be described as an example.

  In the present invention, the ink can be composed of a material that does not cause problems with skin sensitization, and the cured product obtained by using this ink is sensitive even if a small amount of uncured monomer components remain. There is no problem in the productivity, and even if it is touched with a finger or the like, it does not cause skin sensitization, so that high safety can be provided.

<Polymerizable monomer>
Examples of the polymerizable monomer include monofunctional monomers and polyfunctional monomers.
In the present invention, a monofunctional (meth) acrylate is used as a monomer capable of maintaining a sufficiently low viscosity even when a polymer component is blended. Among them, at least one of t-butyl methacrylate, n-pentyl methacrylate, and n-hexyl methacrylate, which is a photopolymerizable monomer having a negative skin sensitization property, is preferable.
The vapor pressures of these monofunctional monomers are 700 Pa (18.5 ° C.), 69.1 Pa (25 ° C.), and 34.7 Pa (20 ° C.), respectively. It is higher than 9.7 Pa (25 ° C.) of benzyl acrylate, which is a drying monomer, and is disadvantageous for drying property. When such a low-viscosity photopolymerizable monomer is blended, volatile thickening may occur in the vicinity of the nozzle. Even in this case, even if it is dried from the initial weight to 70%, if the yield value is within 0.1 Pa, it can be discharged without any problem.

  In the present invention, a polyfunctional (meth) acrylate is further used. In particular, if the monomer has negative skin sensitization, it contains at least one of glycerol dimethacrylate, ethylene oxide-modified trimethylolpropane trimethacrylate, caprolactone-modified dipentaerythritol hexaacrylate, and tricyclodecane dimethanol dimethacrylate. Furthermore, by further blending a polymer or copolymer consisting of at least one selected from styrene, styrene derivatives, acrylic acid and acrylic esters, a polymer having a polyester structure or a chlorinated olefin structure, Good curability as ink and good adhesion to various substrates not subjected to surface treatment can be obtained.

In addition, t-butyl methacrylate, n-pentyl methacrylate, and n-hexyl methacrylate have low viscosity of about 1 to 2 mPa · s at 25 ° C., and the ink can be ejected into the ink jet without any problem in skin sensitization. Although it is an important component for lowering the viscosity, sufficient curability cannot be obtained with these monomers alone.
However, practical curability can be obtained by blending at least one of glycerol dimethacrylate, ethylene oxide-modified trimethylolpropane trimethacrylate, caprolactone-modified dipentaerythritol hexaacrylate, and triclodecane dimethanol dimethacrylate. The SI value indicating the degree of skin sensitization and the degree of skin sensitization will be described later in detail.

The photopolymerizable monomer having negative skin sensitization refers to a compound corresponding to at least one of the following (1) to (3).
(1) Compound having a Stimulation Index (SI value) of less than 3 indicating the degree of sensitization in a skin sensitization test by the LLNA method (Local Lymph Node Assay) (2) MSDS (Chemical Safety Data Sheet) Compound (3) evaluated as “skin sensitization negative” or “no skin sensitization” in the literature [eg Contact Dermatitis 8 223-235 (1982)] or “skin Compounds rated as “no sensitization”

  Regarding (1), for example, “Functional Materials”, September 2005, Vol. 25, no. 9, as shown in P55, when the SI value is less than 3, it is determined that the skin sensitization is negative. The lower the SI value, the lower the skin sensitization. In the present invention, it is preferable to use a monomer having an SI value as low as possible, preferably less than 3, preferably 2 or less, more preferably 1.6 or less.

Moreover, the following (meth) acrylate, (meth) acrylamide, and vinyl ether can also be used together as needed, for example.
Ethylene glycol di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, γ-butyrolactone acrylate, isobornyl (meth) acrylate, formalized trimethylolpropane mono (meth) acrylate, polytetramethylene glycol di (meth) acrylate, trimethylolpropane (meth) acrylate benzoate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate _{[CH 2 = CH-CO- (OC} 2 H 4) n- OCOCH = CH ₂ (n≈9), (n≈14), (n≈23)], dipropylene glycol di (meth) acrylate, tripropylene glycol Koruji (meth) acrylate, polypropylene glycol di methacrylate _{[CH 2 = C (CH 3)} -CO- (OC 3 H 6) n-OCOC (CH 3) = CH 2 (n ≒ 7) ], 1,3 Butanediol diacrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Tricyclodecane dimethanol diacrylate, propylene oxide modified bisphenol A di (meth) acrylate, polyethylene glycol di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, (meth) acryloylmorpholine, 2-hydroxypropyl (meth) acrylic Ami , Propylene oxide modified tetramethylolmethane tetra (meth) acrylate, dipentaerythritol hydroxypenta (meth) acrylate, caprolactone modified dipentaerythritol hydroxypenta (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) Acrylate, trimethylolpropane triacrylate, ethylene oxide modified trimethylolpropane triacrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, caprolactone modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tris ( 2-Hydroxyethyl) isocyanurate tri (meth) acryl Ethoxylated neopentyl glycol di (meth) acrylate, propylene oxide modified neopentyl glycol di (meth) acrylate, propylene oxide modified glyceryl tri (meth) acrylate, polyester di (meth) acrylate, polyester tri (meth) acrylate, Polyester tetra (meth) acrylate, polyester penta (meth) acrylate, polyester poly (meth) acrylate, N-vinylcaprolactam, N-vinylpyrrolidone, N-vinylformamide, polyurethane di (meth) acrylate, polyurethane tri (meth) acrylate, Polyurethane tetra (meth) acrylate, polyurethane penta (meth) acrylate, polyurethane poly (meth) acrylate, triethyleneglycol Divinyl ether, cyclohexanedimethanol divinyl ether, cyclohexanedimethanol monovinyl ether, hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, diethylene glycol divinyl ether, dicyclopentadiene vinyl ether, tricyclodecane vinyl ether, benzyl vinyl ether, ethyl oxetane methyl vinyl ether, triethylene glycol di Vinyl ether, hydroxybutyl vinyl ether, ethyl vinyl ether, etc.

<Polymer component>
In the present invention, the polymer component needs to have good solubility in the monomer component described above. Therefore, it is desirable that the polymer component does not have a cross-linked structure and is a chain. Those having a molecular weight that is too large even in a chain form are preferred to have an average molecular weight of 100,000 or less because the solubility in the ink is lowered and the ink may be excessively thickened by drying and evaporation of the ink.
Furthermore, regarding solubility, it is also important that the polymer component is not very rigid and the crystallinity is not too high. In addition, those that are practically inexpensive and can be easily procured are preferred. Moreover, what has arbitrary acid value and hydroxyl value can also be used for solubility or other convenience. On the other hand, if the blending amount of the polymer component is too large, the viscosity increases due to drying and evaporation of the ink, and the ejection becomes difficult. As described above, the polymer component is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the total monomer components.

  Examples of such polymer components include “Hardlen DX530P” manufactured by Toyobo (polymer having a chlorinated olefin structure, weight average molecular weight 100000, chlorination rate 30%), “Hardlen 14-WL-P” manufactured by Toyobo (chlorinated olefin). Polymer having structure, weight average molecular weight 40000, chlorination rate 27%), “JONCRYL611” manufactured by BASF (styrene / (meth) acrylic acid / α-methylstyrene copolymer, acid value 53 mgKOH / g, weight average molecular weight 8100) Etc.

<Polymer dispersant>
Conventionally known polymer dispersants can be used as the polymer dispersant, but those having a polar functional group are preferable. By having a polar functional group, it becomes easy to adsorb to the pigment, dispersibility is improved, and an ink that easily starts to flow can be created.
Examples of the polymer dispersant include a hydroxyl group-containing carboxylic acid ester, a salt of a long chain polyaminoamide and a high molecular weight acid ester, a salt of a high molecular weight polycarboxylic acid, a salt of a long chain polyaminoamide and a polar acid ester, and a high molecular weight unsaturated. Acid ester, modified polyurethane, modified polyacrylate, polyether ester type anionic activator, naphthalene sulfonic acid formalin condensate salt, polyoxyethylene alkyl phosphate ester, polyoxyethylene nonyl phenyl ether, polyester polyamine, stearylamine acetate, etc. Can be mentioned.

  As such a polymer dispersing agent, commercially available products such as Nippon Lubrizol Solsperse, Enomoto Kasei Disparon, and Ajinomoto Finetech Ajisper can be used.

The content of the polymer dispersion stabilizer is not less than the amount that is saturatedly adsorbed on the pigment, and is preferably 5 or less when the amount that is saturatedly adsorbed without excess or deficiency is 1. If the amount is less than the saturated adsorption amount, the dispersion stability of the pigment is lowered and the yield value increases, and if it exceeds 10% by weight from the saturated adsorption amount, the strength of the ink after curing may be lowered.
It may be difficult to directly determine the saturated adsorption amount, and the pigment adsorption amount / surface area is often substituted.

<Pigment>
As the pigment used in the present invention, known inorganic pigments and organic pigments can be used.
As the black pigment, carbon black produced by a furnace method or a channel method can be used.
Examples of yellow pigments include Pig. Yellow pigments such as Pigment Yellow 1, Pigment Yellow 2, Pigment Yellow 3, Pigment Yellow 12, Pigment Yellow 13, Pigment Yellow 14, Pigment Yellow 16, Pigment Yellow 17, Pigment Yellow 73, Pigment Yellow 74, Pigment Yellow 75, Pigment Yellow 83, Pigment Yellow 93, Pigment Yellow 95, Pigment Yellow 97, Pigment Yellow 98, Pigment Yellow 114, Pigment Yellow 120, Pigment Yellow 128, Pigment Yellow 129, Pigment Yellow 138, Pigment Yellow 150, Pigment Yellow 151, Pigment Yellow 154, Pigment Yellow 155, Pigment Yellow 180, etc. It can be used.

  As magenta pigments, Pig. Red pigments such as Pigment Red 5, Pigment Red 7, Pigment Red 12, Pigment Red 48 (Ca), Pigment Red 48 (Mn), Pigment Red 57 (Ca), Pigment Red 57: 1, Pigment Red 112, Pigment Red 122, Pigment Red 123, Pigment Red 168, Pigment Red 184, Pigment Red 202, Pigment Violet 19, and the like can be used.

  Examples of cyan pigments include Pig. Blue pigments such as Pigment Blue 1, Pigment Blue 2, Pigment Blue 3, Pigment Blue 15, Pigment Blue 15: 3, Pigment Blue 15: 4, Pigment Blue 16, Pigment Blue 22, Pigment Blue 60, Bat Blue 4, Bat Blue 60 or the like can be used.

White pigments or colorless fillers for improving physical properties include alkaline earth metal sulfates such as barium sulfate, alkaline earth metal carbonates such as calcium carbonate, finely divided silicic acid, synthetic silicates, etc. Silicas, calcium silicate, alumina, alumina hydrate, titanium oxide, zinc oxide, talc, clay and the like can be used.
In addition to these pigments, various inorganic pigments and organic pigments can be used as necessary in consideration of physical properties and the like.

  Furthermore, as required, 4-methoxy-1-naphthol, methylhydroquinone, hydroquinone, t-butylhydroquinone, di-t-butylhydroquinone, methoquinone, 2,2'-dihydroxy-3,3'-di (α- Methylcyclohexyl) -5,5'-dimethyldiphenylmethane, p-benzoquinone, di-t-butyldiphenylamine, 9,10-di-n-butoxycyantracene, 4,4 '-[1,10-dioxo-1,10 -Decandiylbis (oxy)] bis [2,2,6,6-tetramethyl] -1-piperidinyloxy and other polymerization inhibitors, higher fatty acid esters having polyether, amino group, carboxyl group and hydroxyl group, side Polydimethylsiloxane having polyether, amino group, carboxyl group or hydroxyl group at the chain or terminal Emissions compounds, polyethers, amino group, carboxyl group, can be used surfactants such as fluoroalkyl compound having a hydroxyl group.

  In preparing the active energy ray-curable composition of the present invention, a part of a polymerizable monomer, a polymer dispersant and a pigment are mixed in advance to obtain a pigment dispersion, which is mixed with the polymerizable monomer and the polymer component. It is desirable to do.

  The blending amount of the pigment is preferably 2.5 to 5 parts by weight with respect to 100 parts by weight of the polymerizable monomer.

<Polymerization initiator>
It is preferable to use a photo radical polymerization initiator in the ink of the present invention. As the photoradical polymerization initiator, one having negative skin sensitization is more preferably used.
(Meth) acrylic acid ester, (meth) acrylamide and its derivatives, and vinyl ether compounds are known to have ionic polymerizability, but ionic polymerization initiators are generally not only expensive but also do not irradiate light. In order to generate slightly strong acid and strong alkali even in the state, special considerations such as providing acid resistance and alkali resistance in the ink supply path in the ink jet coating system are required. For this reason, there is a restriction on the selection of members constituting the inkjet coating system. On the other hand, in the ink of the present invention, it is possible to use a photo radical polymerization initiator that is inexpensive and does not generate strong acid / alkali, so that the ink can be manufactured at low cost and the ink-jet coating system can be easily selected. It becomes. Of course, in the case of using a high energy light source such as electron beam, α, β, γ ray, and X-ray, the polymerization reaction can proceed without using a polymerization initiator. This is well known and will not be described in detail in the present invention.

Examples of the photo radical polymerization initiator include a molecular cleavage type photo polymerization initiator and a hydrogen abstraction type photo polymerization initiator.
Examples of molecular cleavage type photopolymerization initiators include 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane-1 -One, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy -2-methylpropionyl) benzyl] phenyl} -2-methyl-1-propan-1-one, phenylglyoxyc acid methyl ester, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane -1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1,2-dimethylamino-2- (4- Tilbenzyl) -1- (4-morpholin-4-yl-phenyl) butan-1-one, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2, 4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzoylphosphine oxide, 1,2-octanedione- [4- (phenylthio) -2- (o-benzoyloxime)], ethanone-1 -[9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime), [4- (methylphenylthio) phenyl] phenylmethanone, etc. .

Examples of hydrogen abstraction type photopolymerization initiators include benzophenone compounds such as benzophenone, methylbenzophenone, methyl-2-benzoylbenzoate, 4-benzoyl-4'-methyldiphenyl sulfide, phenylbenzophenone, and 2,4-diethyl. Examples include thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, and 1-chloro-4-propylthioxanthone.
An amine can be used in combination as a polymerization accelerator.
Examples thereof include ethyl p-dimethylaminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, methyl p-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, butoxyethyl p-dimethylaminobenzoate, and the like. Is mentioned.

  Among these polymerization initiators, 1-hydroxy-cyclohexyl phenyl ketone, 2-dimethylamino-2- (4-methylbenzyl)-, which is a readily available polymerization initiator having a negative skin sensitization property. One or more selected from 1- (4-morpholin-4-yl-phenyl) butan-1-one and an equimolar mixture of 2,4-diethylthioxanthone and 2-ethylhexyl p-dimethylaminobenzoate Is preferred.

  In the present invention, those containing the following components (A) to (D) are preferred, the monofunctional (meth) acrylate is the compound group (A), the polyfunctional (meth) acrylate is the compound (B), and the skin feel 1-hydroxy-cyclohexyl phenyl ketone, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholine-, which is a low-cost and easily procurable polymerization initiator 4-yl-phenyl) butan-1-one, an equimolar mixture of 2,4-diethylthioxanthone and p-dimethylaminobenzoic acid-2-ethylhexyl is compound group (C) and polymer component (D). When the total of the monomer components is 100 parts by weight, the blending ratio of (A) is preferably 50 to 85 parts by weight. The blending ratio of (B) is preferably 15 to 50 parts by weight. The blending ratio of (C) is preferably 5 to 15 parts by weight. Further, the blending ratio of (D) is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the total monomer components. However, none is limited to this range.

<Organic solvent>
The active energy ray-curable composition of the present invention may contain an organic solvent, but it is preferable not to contain it if possible. If the composition does not contain an organic solvent, especially a volatile organic solvent (VOC (Volatile Organic Compounds) free), the safety of the place where the composition is handled is further improved, and it is possible to prevent environmental pollution. . The “organic solvent” means a general non-reactive organic solvent such as ether, ketone, xylene, ethyl acetate, cyclohexanone, and toluene, and should be distinguished from a reactive monomer. is there. Further, “not including” an organic solvent means that it does not substantially include, and is preferably less than 0.1% by mass.

<Viscosity>
The viscosity of the active energy ray-curable composition of the present invention may be appropriately adjusted according to the use and application means, and is not particularly limited. For example, when applying a discharge means that discharges the composition from a nozzle The viscosity in the range of 20 ° C. to 65 ° C., desirably the viscosity at 25 ° C. is preferably 3 to 40 mPa · s, more preferably 5 to 15 mPa · s, and particularly preferably 6 to 12 mPa · s. Moreover, it is particularly preferable that the viscosity range is satisfied without including the organic solvent. In addition, the above-mentioned viscosity uses a cone rotor (1 ° 34 '× R24) with a cone plate type rotational viscometer VISCOMETER TVE-22L manufactured by Toki Sangyo Co., Ltd., with a rotation speed of 50 rpm and a constant temperature circulating water temperature of 20 ° C. It can be measured by appropriately setting in the range of ~ 65 ° C. VISCOMATE VM-150III can be used for temperature adjustment of circulating water.

<About yield value>
The active energy ray-curable composition of the present invention includes a yield value of the active energy ray-curable composition and a yield value when the active energy ray-curable composition is dried to 70 mass% of the initial weight. All of these are 0.1 Pa or less. Even if the active energy ray-curable composition is dried from the initial weight to 70% to cause volatile thickening, it can be discharged without any problem if the yield value is within 0.1 Pa.

(Use)
The active energy ray-curable composition of the present invention is not particularly limited as long as the active energy ray-curable material is generally used in the field, and can be appropriately selected according to the purpose. For example, a molding resin, It can be applied to paints, adhesives, insulating materials, release agents, coating materials, sealing materials, various resists, and various optical materials.

  Furthermore, the active energy ray-curable composition of the present invention can be used as an active energy ray-curable ink to form two-dimensional characters and images, and also forms a three-dimensional stereoscopic image (three-dimensional modeled object). It can also be used as a material for three-dimensional modeling. Among these, it is preferable to use as an active energy ray curable ink, and an inkjet ink is particularly preferable.

Paper, plastic, metal, ceramic, glass, or a composite material thereof is used as a substrate to be coated with the active energy ray-curable composition. Since an effect can be expected, it is also practical to use a water-based ink or oil-based ink that does not quickly dry. On the other hand, it is more practical to use ink that provides quick drying on non-permeable substrates such as matte coated paper, gloss coated paper, plastic film, plastic molding, ceramic, glass, metal, It is desirable to use the photopolymerizable ink in the present invention because it is cured immediately by light irradiation.
The present invention is particularly suitable for the non-permeable substrate as described above, and polypropylene is particularly suitable. In some polypropylene substrates, corona treatment is performed for the purpose of activating the surface and improving adhesion, but such a process that generates electric sparks is a photopolymerizable substance that is a hazardous material under the Fire Service Act. It is usually difficult at the site of inkjet ink application. In the present invention, sufficient adhesion can be obtained without such treatment.

As a three-dimensional modeling material, for example, as a binder between powder particles used in a powder lamination method which is one of three-dimensional modeling methods, and as shown in FIG. 2 described later, an active energy ray-curable composition is used. A material jet method (stereolithography method) in which three-dimensional modeling is performed by sequentially stacking materials that are discharged to a predetermined region and irradiated with active energy rays and cured, as shown in FIG. 3, an active energy ray curable composition A solid body in a stereolithography method or the like in which a storage pool (container) 1 of an object 5 is irradiated with an active energy ray 4 to form a hardened layer 6 having a predetermined shape on the movable stage 3, and this is sequentially stacked to form a solid body It can be used as a material constituting material.
A three-dimensional modeling apparatus for modeling a three-dimensional modeled object using such an active energy ray-curable composition can use a known one, and is not particularly limited. A thing provided with a supply means, a discharge means, an active energy ray irradiation means, etc. can be used.

(Active energy ray-curable composition container)
The active energy ray-curable composition storage container of the present invention means a container in which the active energy ray-curable composition is stored, and is preferably used for the above-described applications.
For example, when the active energy ray-curable composition of the present invention is used for ink, the container in which the ink is stored can be used as an ink cartridge or an ink bottle. This eliminates the need for direct contact with the ink and prevents dirt on fingers and clothes. In addition, foreign matters such as dust can be prevented from entering the ink. Further, the shape, size, material, and the like of the container itself may be suitable for use and usage, and are not particularly limited, but the material is preferably light-shielding.

(ink cartridge)
The ink of the present invention can be stored in a container and used as an ink cartridge. The container is not particularly limited, and its shape, structure, size, material, etc. can be appropriately selected according to the purpose. For example, a container having an ink bag formed of an aluminum laminate film, a resin film, etc. Is preferred.
The ink cartridge containing ink will be described with reference to FIGS.
FIG. 4 is a schematic view showing an example of the ink bag 241 of the ink cartridge, and FIG. 5 is a schematic view showing the ink cartridge 200 containing the ink bag 241 shown in FIG.

  As shown in FIG. 4, ink is filled into the ink bag 241 from the ink inlet 242, the air remaining in the ink bag is exhausted, and then the ink inlet 242 is closed by fusion. In use, the needle of the apparatus main body is pierced into the ink discharge port 243 made of a rubber member and supplied to the apparatus. The ink bag 241 is formed of a packaging member such as a non-permeable aluminum laminate film. As shown in FIG. 5, the ink cartridge 200 is usually housed in a plastic cartridge case 244 and detachably mounted on an apparatus for forming various cured products, for example, an ink jet recording apparatus.

  The ink cartridge containing ink is preferably detachable from a cured product forming apparatus, preferably an ink jet recording apparatus. Thereby, replenishment and replacement of ink can be simplified, and workability can be improved.

(2D or 3D image forming method and 2D or 3D image forming apparatus)
The two-dimensional or three-dimensional image forming method in the present invention includes at least an irradiation step of irradiating an active energy ray to cure the active energy ray-curable composition, and the two-dimensional or three-dimensional image formation in the present invention. The apparatus includes irradiation means for irradiating the active energy ray-curable composition with active energy rays, and an accommodating portion for accommodating the active energy ray-curable composition. You may accommodate the said active energy ray hardening-type composition storage container in this storage part. Furthermore, you may have the discharge process and discharge means which discharge an active energy ray hardening-type composition. A method for discharging is not particularly limited, and examples thereof include a continuous injection type and an on-demand type. Examples of the on-demand type include a piezo method, a thermal method, and an electrostatic method.

FIG. 1 is an example of an image forming apparatus provided with an ink jet ejection unit. Ink is ejected to the recording medium 22 supplied from the supply roll 21 by each color printing unit 23a, 23b, 23c, 23d including ink cartridges and discharge heads of active energy ray curable inks of yellow, magenta, cyan, and black. Is done. Thereafter, the light is cured by irradiating active energy rays from the light sources 24a, 24b, 24c, and 24d for curing the ink, thereby forming a color image. Thereafter, the recording medium 22 is conveyed to the processing unit 25 and the printed matter winding roll 26. Each of the printing units 23a, 23b, 23c, and 23d includes a heating unit that heats the ink in the ink discharge unit. If necessary, a mechanism for cooling the recording medium to about room temperature by contact or non-contact may be provided. In addition, for a recording medium that moves intermittently according to the ejection head width, a serial method in which ink is ejected onto the recording medium by moving the head, or the recording medium is moved continuously and held at a fixed position. Any ink jet recording apparatus of a line system in which ink is ejected from a head onto a recording medium can be applied.
The recording medium 22 is not particularly limited, and examples thereof include paper, a film, a metal, a composite material thereof, and the like, and may be a sheet shape. Moreover, even if it is the structure which enables only single-sided printing, the structure which also enables double-sided printing may be sufficient.
Further, the active energy ray irradiation from the light sources 24a, 24b, and 24c may be weakened or omitted, and the active energy ray may be irradiated from the light source 24d after printing a plurality of colors. Thereby, energy saving and cost reduction can be achieved.
The recorded matter recorded by the ink of the present invention is not only printed on a smooth surface such as ordinary paper or resin film, but also printed on a surface to be printed having irregularities, such as metal or ceramic. It includes those printed on a printing surface made of various materials. Further, by stacking two-dimensional images, it is possible to form an image having a stereoscopic effect (an image composed of two and three dimensions) or a three-dimensional object.

  FIG. 2 is a schematic view showing an example of another image forming apparatus (three-dimensional stereoscopic image forming apparatus) used in the present invention. The image forming apparatus 39 in FIG. 2 discharges the first active energy ray-curable composition from the modeling object discharge head unit 30 by using a head unit (movable in the AB direction) in which inkjet heads are arranged. A second active energy ray-curable composition having a composition different from that of the first active energy ray-curable composition is discharged from the head units 31 and 32, and these respective compositions are cured by the adjacent ultraviolet irradiation means 33 and 34. While laminating. More specifically, for example, the second active energy ray-curable composition is ejected from the support ejection head units 31 and 32 on the model support substrate 37 and solidified by irradiation with active energy rays. After forming the first support layer having the reservoir, the first active energy ray-curable composition is discharged from the ejection head unit 30 for a molded article into the reservoir and is solidified by irradiation with active energy rays. Then, the step of forming the first modeled object layer is repeated a plurality of times while lowering the stage 38 movable in the vertical direction in accordance with the number of stacking, thereby stacking the support layer and the modeled object layer to form the three-dimensional modeled object 35. Is produced. Thereafter, the support laminate 36 is removed as necessary. In FIG. 2, only one shaped article discharge head unit 30 is provided, but two or more shaped article discharge head units 30 may be provided.

(Hardened products and molded products)
The present invention also includes a cured product obtained by curing the active energy ray-curable composition and a molded product obtained by processing a structure in which the cured product is formed on a substrate such as a recording medium.

  The cured product of the present invention is obtained by curing the active energy ray-curable composition of the present invention with active energy rays. For example, a coating film (image) on a substrate obtained by using an inkjet discharge device. On the other hand, by subsequently irradiating with ultraviolet rays, the coating film on the substrate is quickly cured to obtain a cured product.

  There is no restriction | limiting in particular as a base material which can be used in the formation method of the hardened | cured material of this invention, According to the objective, it can select suitably, For example, paper, a plastics, a metal, a ceramic, glass, or these composites Materials and the like.

  Among these, a plastic substrate is preferable from the viewpoint of processability, for example, polyethylene, polypropylene, polyethylene terephthalate, polycarbonate, ABS resin, polyvinyl chloride, polystyrene, other polyester, polyamide, vinyl-based material, acrylic resin, or these. Examples include plastic films made of composite materials and plastic moldings.

The molded product according to the present invention is obtained by molding a decorative body having a surface decoration made of the cured product of the present invention on a base material by stretching or punching.
The molded product is suitably used for applications that require decoration of surfaces such as automobiles, OA equipment, electrical / electronic equipment, cameras, and operation panel panels.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

(Preparation of carbon black dispersion 1)
Carbon black (Mitsubishi Chemical # 5B) and amino group-containing polyester polymer dispersant (Solsperse 32000, Nippon Lubrizol Co., Ltd.) are added to a photopolymerizable monomer (“n-Amylmethacrylate” manufactured by Zhangjiagang Render Chemical). In addition, a carbon black dispersion 1 having a carbon black content of 15% by weight and a polymer dispersant content of 0.9% by weight was prepared.

(Preparation of carbon black dispersion 2)
Carbon black (Mitsubishi Chemical # 5B) and amino group-containing polyester polymer dispersant (Solsperse 32000, Nippon Lubrizol Co., Ltd.) are added to a photopolymerizable monomer (“n-Amylmethacrylate” manufactured by Zhangjiagang Render Chemical). In addition, a carbon black dispersion 2 having a carbon black content of 15% by weight and a polymer dispersant content of 5% by weight was prepared.

(Preparation of carbon black dispersion 3)
Carbon black (Mitsubishi Chemical Corporation # 5B) and amino group-containing polyester polymer dispersant (Solsperse 32000, Nippon Lubrizol Co., Ltd.) are added to the photopolymerizable monomer (t-butyl methacrylate "Acryester TB" manufactured by Mitsubishi Rayon). A carbon black dispersion 3 having a carbon black content of 15% by weight and a polymer dispersant content of 5% by weight was prepared.

(Preparation of carbon black dispersion 4)
Add carbon black (Mitsubishi Chemical # 5B) and amino group-containing polyester polymer dispersant (Solsperse 32000, Nippon Lubrizol Co., Ltd.) to photopolymerizable monomer (n-hexyl methacrylate “n-Hexyl Methacrylate” manufactured by Tokyo Chemical Industry). A carbon black dispersion 4 having a carbon black content of 15% by weight and a polymer dispersant content of 5% by weight was prepared.

<Relationship between amount of polymer dispersant adsorbed on carbon black and blending ratio of polymer dispersant>
With respect to the carbon black dispersions 1 to 4, the relationship between the polymer dispersant adsorption amount of carbon black and the blending ratio of the polymer dispersant was examined. The result is shown in FIG.

The measurement results of the amount of adsorption of the polymer dispersant in the above carbon black dispersions 1 to 4 will be described in detail with reference to FIG. In FIG. 6, the blending ratio of the polymer dispersant indicates the amount of the polymer dispersant in the carbon black dispersion.
It is obvious that the amount of adsorption is 0 when the polymer dispersant content is 0%. When the blending ratio of the polymer dispersant was 0% to 1%, the amount of adsorption increased with increasing blending ratio. When the blending ratio of the polymer dispersant was 1% or more, the adsorption amount was constant. Therefore, if the blending ratio of the polymer dispersant is less than 1%, the adsorption is not saturated, and if the blending ratio of the polymer dispersant is 1% or more, the adsorption is saturated, and the blending ratio of the polymer dispersant is 1%. It can be seen that the polymer dispersant is adsorbed without excess and deficiency, and when the blending ratio of the polymer dispersant exceeds 1%, 5% and 10%, it is excessive blending with respect to saturated adsorption.

<Measurement of amount of polymer dispersant adsorbed on carbon black>
The adsorption amount was measured as follows.
(1) The dispersion was centrifuged, and the obtained solid content was washed with acetone, and only the carbon black adsorbed with the polymer dispersant was taken out.
(2) The carbon black collected above was baked at 450 ° C., and the weight loss before and after calcination was taken as the adsorption amount. In addition, it has been confirmed in advance that carbon black itself has a slight weight loss under the same firing conditions and almost no change in state. However, the amount of adsorption has been corrected by taking into account the slightly observed weight loss of carbon black itself. Was calculated.
(3) The amount of adsorbing polymer dispersant per unit weight of carbon black is converted into the specific surface area of carbon black used (29 m ² / g: catalog value), and the amount of adsorption per carbon black surface area is shown in FIG. It was.

<SI value evaluation method>
SI value was measured as follows according to the skin sensitization test by LLNA method (Local Lymph Node Assay).
[Test material]
《Positive control substance》
Α-hexylcinnamaldehyde (HCA; manufactured by Wako Pure Chemical Industries, Ltd.) was used as a positive control substance.
《Medium》
As a medium, a mixed solution in which acetone (manufactured by Wako Pure Chemical Industries, Ltd.) and olive oil (manufactured by Fujimi Pharmaceutical) were mixed at a volume ratio of 4: 1 was used.
《Animals used》
For each of the test substance, the positive control, and the vehicle control, female mice were acclimated for 8 days including 6 days of quarantine. During quarantine and habituation, no abnormalities were observed in all animals. Using the body weight measured 2 days before the start of sensitization, it was divided into 2 groups (4 animals / group) so that the body weight of the individual was within ± 20% of the total body weight by the random extraction method according to the weight group. . The age of the animals at the start of sensitization was 8-9 weeks. Animals that were excluded by grouping were excluded from the study.
The animals used were identified by applying oil-based ink to the tail throughout the test period, and the cages were identified by labeling.
《Creation environment》
Animals are used throughout the entire breeding period including quarantine and acclimatization period, temperature 21 to 25 ° C., relative humidity 40 to 70%, ventilation rate 10 to 15 times / hour, light / dark cycle 12 hours sense (lights from 7 o'clock to 19 o'clock) Breeding in the breeding room of the barrier system set to “off”.
The cage made of polycarbonate was used as the breeding cage. The animals used were kept at 4 / cage.
The feed used was a solid feed MF for experimental animals (manufactured by Oriental Yeast Co., Ltd.), and was used freely by the animals used. The drinking water was allowed to be freely consumed by the animals using a water supply bottle with tap water added with sodium hypochlorite (Purelux, Oyalax) so that the chlorine concentration was about 5 ppm. Sun flakes (fir, electric planer shavings, manufactured by Charles River Japan) were used for the flooring. The feed and breeding equipment were each autoclaved (121 ° C., 30 minutes).
Cages and bedding were exchanged at the time of grouping and the auricular lymph node intake day (at the time of removal from the breeding room), and the water bottles and racks were exchanged at the time of grouping.

[Test method]
<< Group composition >>
Table 1 shows the group structure used in the SI value measurement test.

[Preparation]
<Test substance>
Table 2 shows the weighing conditions of the test substance. The test substance was weighed into a volumetric flask, and the volume was adjusted to 1 mL while adding the medium. The preparation liquid was put in a light-tight airtight container (made of glass).

《Positive control substance》
Approximately 0.25 g of HCA was accurately weighed, and a 25.0 w / v% solution was prepared as 1 mL while adding the medium. The preparation was placed in a light-tight airtight container (made of glass).
<< BrdU >>
200 mg of 5-bromo-2'-deoxyuridine (BrdU, manufactured by Nacalai Tesque) was accurately weighed into a volumetric flask, physiological saline (manufactured by Otsuka Pharmaceutical Co., Ltd.) was added, and ultrasonic irradiation was performed to dissolve. Thereafter, the volume was adjusted to 20 mL to prepare a 10 mg / mL solution (BrdU preparation solution). The preparation solution was sterilized by filtration using a sterilized filtration filter and placed in a sterilized container.
《Preparation time and storage period》
The positive control substance preparation solution was prepared the day before the start of sensitization and stored in a cold place except when it was used. Media and test substance preparations were prepared on each sensitization day. BrdU solution was prepared 2 days before administration and stored in a cold place until the day of administration.

[Sensitization and BrdU administration]
《Sensitization》
25 μL of each test substance and positive control substance preparation and medium were applied to both ears of the animal. A micro pipettor was used for coating. This operation was performed once a day for 3 consecutive days.
Administration of BrdU
About 48 hours after the final sensitization, the BrdU preparation solution was intraperitoneally administered at 0.5 mL per animal.

[Observation and inspection]
《General condition》
All animals used in the test were observed at least once a day from the date of sensitization to the date of collecting auricular lymph nodes (the date of removal from the breeding room). In addition, in the calculation method of the observation date, the sensitization start date was set to Day1.
<< Weighing >>
Body weights were measured on the date of sensitization and the date of collection of auricular lymph nodes (the date of removal from the breeding room). Moreover, the average value and standard error of the body weight for every group were calculated.
《Auricular lymph node collection and weight measurement》
Approximately 24 hours after BrdU administration, animals were euthanized and auricular lymph nodes were collected. The surrounding tissues were removed and the bilateral auricular lymph nodes were weighed together. Moreover, the average value and standard error of the auricular lymph node weight for each group were calculated. After weighing, each individual was stored frozen in a biomedical freezer set at -20 ° C.
<Measurement of BrdU incorporation>
After returning the auricular lymph node to room temperature, it was ground and suspended while adding physiological saline. After filtering this suspension, 3 wells of each individual were dispensed into 96-well microplates, and the BrdU incorporation was measured by ELISA. Each reagent was obtained from a multi-plate reader (FLUOstar OPTIMA, BMG LABTECH) using a commercially available kit (Cell Proliferation ELISA, BrdU colorimetric, Cat. No. 1647229, manufactured by Roche Diagnostics). For the individual absorbance (OD370nm-OD492nm, BrdU incorporation amount), the average value of 3 wells was taken as the BrdU measurement value of each individual.

[Evaluation of results]
<< Calculation of Stimulation Index (SI) >>
As shown by the following formula, the measured value of BrdU of each individual was gradually decreased by the average value of BrdU measured values of the vehicle control group, and the SI value of each individual was calculated. The SI value of each test group was the average value of SI of each individual. The SI value was rounded off to the first decimal place by rounding off the second decimal place.

(Examples 1-4, Comparative Examples 1-4, Reference Examples 1-2)
The materials of the following (A) to (D) and the above carbon black dispersions 1 to 4 were mixed at the blending ratios (numerical values are parts by weight) shown in the respective columns of the examples in Table 3 to obtain black ink.
(A) Monofunctional (meth) acrylate (B) Multifunctional (meth) acrylate (C) Photoradical polymerization initiator having negative skin sensitization (D) Polymer polymer (Since the polymer component has a high molecular weight, the skin Difficult to pass through, usually without skin sensitization)

  The details of A1 to A3, B1 to B4, C1 to C2, and D1 to D6 in Table 3 are as follows. The numerical value in parentheses at the end is the SI value in the LLNA test of (1) above, and “negative” or “none” is the literature of (2) above, or the MSDS (chemical safety data sheet) of (3) above Were evaluated as “negative skin sensitization” or “no skin sensitization”. “Positive” is accompanied by a warning phrase “R43” indicating that there is a problem with skin sensitization in the risk phrase notation rule in the European directive.

A1: n-pentyl methacrylate Evaluation by “n-Amyl Methacrylate” (negative) literature made by Zhangjiagang Render Chemical (test method: maximization method)
A2: t-Butyl methacrylate “Acryester TB” manufactured by Mitsubishi Rayon (negative) Evaluation in literature (Test method: Maximization method)
A3: n-hexyl methacrylate Evaluation by “n-Hexyl Methacrylate” (negative) literature manufactured by Tokyo Chemical Industry (test method: maximization method)

B1: Glycerol dimethacrylate Shin-Nakamura Chemical "701" (1.2)
B2: Tricyclodecane dimethanol dimethacrylate “DCP” (1.3) manufactured by Shin-Nakamura Chemical
B3: Ethylene oxide modified trimethylolpropane trimethacrylate “TMPT-3EO” (1.0) manufactured by Shin-Nakamura Chemical
B4: Caprolactone-modified dipentaerythritol hexaacrylate Evaluation by Nippon Kayaku (negative) MSDS (Test method: OECD test guideline 406)

C1: 1-hydroxy-cyclohexyl phenyl ketone “Irgacure 184” manufactured by BASF (none) Evaluation by MSDS (test method: OECD test guideline 406)
C2: 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-yl-phenyl) butan-1-one “Irgacure 379” manufactured by BASF (none) Evaluation by MSDS (Test method) : OECD Test Guideline 406)

D1: Polymer having a chlorinated olefin structure Weight average molecular weight 100000 Chlorination rate 30% “Hardlen DX530P” manufactured by Toyobo
D2: Polymer having a chlorinated olefin structure Weight average molecular weight 40000 Chlorination rate 27% "Hardlen 14-WL-P" manufactured by Toyobo
D3: Styrene / (meth) acrylic acid / α-methylstyrene copolymer Acid value 53 mg KOH / g Weight average molecular weight 8100 “JONCRYL611” manufactured by BASF
D4: Polymer having a chlorinated olefin structure Weight average molecular weight 200000
D5: Polymer having a chlorinated olefin structure Weight average molecular weight 90000
D6: Polymer having a chlorinated olefin structure Weight average molecular weight 110000

  The yield values and inkjet discharge properties of Examples 1 to 4, Comparative Examples 1 to 4, and Reference Examples 1 to 2 were evaluated by the following methods. The results are shown in Table 4 below.

(Yield value)
The yield value was calculated from Casson's Plot shown by the following formula (1) based on the viscosity value measured by changing the shear rate.
√τ = √η∞ × √D + √τ0 (1)
(Where τ is the shear stress (Pa), D is the shear rate (1 / sec), √η∞ and √τ0 are constants.)
Casson's Plot graphed with √τ on the vertical axis and √D on the horizontal axis is widely used for analyzing rheological properties because good linearity can be obtained in a pigment dispersion system. Here, √τ0 corresponds to the intercept of the vertical axis in the graph, and the square thereof, that is, τ0 is the yield value.
The Casson's Plot of the above data is not shown here, but good linearity has been confirmed, and it has been confirmed that the application of the above formula is appropriate.

(Inkjet ejection)
Using an inkjet discharge head GEN4 (nozzle diameter 26 μm) manufactured by Ricoh Printing Systems, the black ink was heated to 50 ° C., the head cap was removed, and the discharge evaluation after being left for 10 minutes was performed. A predetermined idle discharge was performed before the discharge evaluation.
○: Can be discharged ×: Cannot be discharged (concentration)
Furthermore, a solid image is printed on a PC substrate (white) with the above system, cured by irradiation with a meta-hara lamp with an integrated light quantity of 1000 mJ / cm ² , density measurement is performed with Model 939 of Xrite, and if it is 1.2 or more, 1 Less than 2.

* 1: Even if the container was tilted, the fluidity was so poor that it did not flow due to its own weight, and the viscosity could not be measured because it exceeded the measurement upper limit of the viscometer used, and the yield value could not be obtained.
* 2: It was difficult to supply ink to the ejection head via the ink flow path, and ejection evaluation could not be performed.
* 3: The concentration could not be measured because it did not cure.

Since Comparative Example 1 uses a carbon black dispersion liquid in which the polymer dispersant is not saturatedly adsorbed to carbon black, it is considered that sufficient dispersibility is not obtained. As a result, the yield value became very large, and inkjet discharge could not be performed.
In Comparative Example 2, since the blending amount of the polymer component is high, it is considered that the viscosity is not sufficiently measured when the ink weight is dried and evaporated to 70%, and it has a considerably large yield value. Even it was difficult to do.
In Comparative Example 3, the molecular weight of the polymer component is high, and when the ink weight evaporates to 70%, the viscosity becomes high and the fluidity is so low that the sexual viscosity cannot be measured. Even the evaluation was difficult.
In Comparative Example 4, the molecular weight of the polymer component was high, and the yield value exceeded 0.1 Pa.
In Reference Example 1, the pigment concentration was low and the desired concentration was not obtained.
In Reference Example 2, the pigment concentration was high, causing poor curing.
Examples 1 to 4 use a carbon black dispersion liquid in which a polymer dispersant is saturated and adsorbed on carbon black, and use a diluted solution in which the polymer dispersant is dissolved in advance, and saturated adsorption to carbon black in the ink. By adding the polymer dispersing agent, the dispersibility of the carbon black was not impaired even by dilution accompanying ink formation, and as a result, the yield value could be suppressed to 0.1 Pa or less and inkjet discharge could be performed.

Example 5
(Cyan ink composition)
A cyan dispersion was prepared with the same composition except that the carbon black (# 5B manufactured by Mitsubishi Chemical Corporation) in the carbon black dispersion 2 was changed to cyanine blue 4933M (manufactured by Dainichi Seika Kogyo Co., Ltd.), and the carbon black dispersion was cyan dispersed. A cyan ink was prepared with the same composition as in Example 1 except that the liquid was used.

Example 6
(Magenta ink composition)
A magenta dispersion was prepared with the same composition except that carbon black (Mitsubishi Chemical Corporation # 5B) in Carbon Black Dispersion 2 was changed to KET Red 301 (Dainippon Ink Chemical Co., Ltd.), and the carbon black dispersion was magenta dispersed. A magenta ink was prepared with the same composition as in Example 1 except that the liquid was used.

Example 7
(Yellow ink composition)
A yellow dispersion was prepared with the same composition except that carbon black (# 5B manufactured by Mitsubishi Chemical Corporation) of the carbon black dispersion 2 was changed to Lionol Yellow 1405G (manufactured by Toyo Ink), and the carbon black dispersion was changed to a yellow dispersion. A yellow ink was prepared with the same composition as in Example 1 except for the above.

  In Examples 5 to 7, the yield value and the inkjet dischargeability were evaluated in the same manner as in Example 1, and the results shown in Table 5 were obtained.

  As in Example 1, a pigment dispersion in which a polymer dispersant is saturated and adsorbed without excess or deficiency is used, and a saturated solution is used to dissolve and adsorb to a pigment in ink in a saturated manner. Addition of the polymer dispersant did not impair the dispersibility of the pigment even by dilution accompanying ink formation, and as a result, the yield value could be suppressed to 0.1 Pa or less, and inkjet discharge could be performed.

(Figure 1)
DESCRIPTION OF SYMBOLS 21 Supply roll 22 Recording medium 23, 23a, 23b, 23c, 23d Printing unit 24a, 24b, 24c, 24d Light source 25 Processing unit 26 Printed material winding roll (FIG. 2)
39 Image forming apparatus 30 Modeling object ejection head unit 31, 32 Supporting body ejection head unit 33, 34 Ultraviolet irradiation means 37 Modeling object support substrate 38 Stage 35 Three-dimensional object 36 Support layer stacking unit (FIG. 3)
1 Storage pool (container) 1
DESCRIPTION OF SYMBOLS 3 Movable stage 4 Active energy ray 5 Active energy ray hardening-type composition 6 Hardened layer (FIG. 4, FIG. 5)
200 Ink cartridge with ink 241 Ink bag 242 Ink inlet 243 Ink outlet 244 Cartridge case

JP 2002-265848 A JP 2009-258619 A JP 2008-101099 A JP 2004-182664 A JP 2013-112691 A

Claims (14)

A non-aqueous active energy ray-curable composition comprising a polymerizable monomer, a polymer component, a polymer dispersant, and a pigment,
Both the yield value of the active energy ray-curable composition and the yield value when the active energy ray-curable composition is dried to 70 mass% of the initial weight are 0.1 Pa or less. A characteristic active energy ray-curable composition.   2. The active energy ray-curable composition according to claim 1, wherein the polymer dispersant contains an amount more than that which is saturatedly adsorbed to the pigment.   The active energy ray-curable composition according to claim 1 or 2, wherein the polymer component has an average molecular weight of 100,000 or less.   The active energy ray-curable composition according to any one of claims 1 to 3, wherein the blending amount of the polymer component is 0.1 to 20 parts by weight with respect to 100 parts by weight of the polymerizable monomer. .   The active energy ray-curable composition according to claim 1, wherein the amount of the pigment is 2.5 to 5 parts by weight with respect to 100 parts by weight of the polymerizable monomer.   The active energy ray-curable composition according to any one of claims 1 to 5, wherein the polymerizable monomer has an SI value of less than 3.   An active energy ray-curable ink comprising the active energy ray-curable composition according to any one of claims 1 to 6.   The active energy ray-curable ink according to claim 7, which is an ink jet ink.   A three-dimensional modeling material comprising the active energy ray-curable composition according to any one of claims 1 to 6.   An active energy ray-curable composition storage container comprising the active energy ray-curable composition according to any one of claims 1 to 6.   Irradiation means for irradiating the active energy ray-curable composition according to any one of claims 1 to 6 formed on a substrate with active energy rays, and a housing portion for accommodating the active energy ray-curable composition; And a two-dimensional or three-dimensional image forming apparatus.   It has an irradiation process of irradiating an active energy ray curable composition according to any one of claims 1 to 6 formed on a substrate with an active energy ray to cure the active energy ray curable composition. A two-dimensional or three-dimensional image forming method characterized.   Hardened | cured material obtained by hardening | curing the active energy ray hardening-type composition in any one of Claims 1-6 with an active energy ray. A molded product obtained by stretching or punching the cured product according to claim 13.