JP2021014492A - Cationic polymerizable color ink composition for flexographic printing, ink set, and laminate - Google Patents

Abstract

To provide a cationic polymerizable color ink for flexographic printing not hindering curability of a cationic polymerizable silicone composition used as a releasing agent, having coated film properties necessary for an adhesive label, and having adequacy for flexographic printing, an ink set for an adhesive label composed of the cationic polymerizable color ink composition for flexographic printing, and a polymerizable clear ink composition, and a laminate.SOLUTION: The cationic polymerizable color ink composition for flexographic printing is a cationic polymerizable color ink composition for flexographic printing including a coloring agent, a cationic polymerization initiator, and a cationic polymerizable compound, where the cationic polymerizable compound includes an epoxy compound (A) having a bisphenol A structure, an alicyclic epoxy compound (B), and an oxetane compound (C), the weight average molecular weight of the epoxy compound (A) is 400-2,000, and a basic compound is substantially not contained.SELECTED DRAWING: None

Description

The present invention provides a cationically polymerizable color ink composition for flexographic printing used for an adhesive label, a cationically polymerizable color ink composition for flexographic printing, an ink set for an adhesive label having the polymerizable clear ink composition, and the same. The present invention relates to a laminate using an ink set.

In recent years, in supermarkets and the like, a portable auto labeler or handler labeler automatically sends adhesive label paper one by one, and a label printed with a special sale price such as a time sale is attached to a product wrapped in a paper container or a plastic film. It is often attached. Adhesive label paper used for portable auto labelers and handler labels has an ink layer printed on the surface of a base material made of high-quality paper or coated paper so that it is noticeable, and adhesive (pressure-sensitive adhesive) processing is applied to the back surface. It is a roll of paper. In the adhesive label paper, what is called a separator such as a release paper or a plastic film is superposed on the adhesive surface so that the adhesive layer (back surface) and the front surface can be smoothly peeled (not adhered). Therefore, when the label is used, the separator is peeled off and discarded. Therefore, a method of not using the separator has been studied from the viewpoint of environment and cost.

For example, Tokusho 03-128975 discloses an ultraviolet curable epoxy silicone / polyol-based release composition, and a silicone composition containing polyorganosiloxane as a main component is described.
Since it has peelability to an adhesive substance, by coating the surface of paper, plastic film, etc. and providing a release layer, adhesion on the back surface can be suppressed, so that a separator is not required. Thermosetting type and ultraviolet curable type are known as silicone compositions used as such a release layer. Various studies have been conducted on the ultraviolet curable type because it cures instantly by irradiation with ultraviolet rays, saves energy as compared with the thermosetting type, and the equipment is inexpensive.

Furthermore, the UV curable silicone composition is radically polymerized by the curing mechanism.
There are hydrosilylation reaction type and cationic polymerization type. Among them, the cationic polymerization type has been widely used because it is not affected by oxygen during curing unlike the radical polymerization type, the coating film shrinks less after curing, and the peeling performance can be easily controlled.

However, the cationically polymerizable ultraviolet curable silicone composition is insufficiently cured due to the amine compound and the basic compound contained in the plastic film or synthetic paper as the base material, and the peeling performance that is satisfactory cannot be obtained. There is a problem that the adhesion between the compound and the cationically polymerizable ultraviolet curable silicone composition is lowered. Similarly, when the cationically polymerizable ultraviolet curable silicone composition is applied onto the ink layer, there is a problem that the substance contained in the ink is greatly affected. For example, when a radically polymerizable curable offset ink containing a pigment, which has been increasingly used due to its quick-drying property and high production in recent years, is used for the ink layer, it is added for the purpose of improving the curability of the ink. There is a problem that a basic compound such as an amine compound or a basic dispersant used as a pigment dispersant hinders the curing of a cationically polymerizable ultraviolet curable silicone composition, so that satisfactory peeling performance cannot be obtained. It was.

Further, there is also a problem that the adhesion between the ink layer and the base material layer is lowered with time because the compound contained in the adhesive layer is transferred to the ink layer through the release layer.

In order to solve such a problem, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2002-240203)
) Discloses a release base material having a sealing layer with an ultraviolet curable sealant between the base material and the cationically polymerizable ultraviolet curable silicone release agent. However, when a radically polymerizable curable ink using a basic compound such as an amine compound or a basic dispersant is printed on the ink layer, there is a problem that a sufficient effect cannot be obtained. When the amine compound is removed from the radically polymerizable curable ink, the curability of the cationically polymerizable ultraviolet curable silicone composition is improved, but in the radically polymerizable curable ink containing 5% or more of the pigment, the pigment is ultraviolet. There is also a problem that curing failure occurs because the permeation is hindered. Further, Patent Document 1 does not consider the poor adhesion caused by the compound migrating from the adhesive layer.

Further, when the ink used for the ink layer is for offset printing, complicated work such as adjusting the amount of ink and the amount of water is required during printing, which causes a problem in productivity. Therefore, the ink layer does not require complicated work and has a relatively low printing cost as compared with offset printing, and covers a wide range from a penetrating base material such as paper to a non-penetrating base material such as a plastic film. There has been a demand for printing by flexographic printing that can use a recording medium. Further, there is a demand for an ultraviolet curable flexo ink that does not require a drying process for removing an organic solvent or water and has high productivity.

Examples of the ultraviolet curable flexographic ink include Patent Document 2 (Japanese Patent Laid-Open No. 2007-2325).
6) discloses an active energy ray-curable flexographic ink containing an oxetane compound, a vinyl ether compound, or an epoxy compound. However, since a basic compound such as a basic dispersant or an amine compound is used, it is not possible to solve the curing failure of the cationically polymerizable ultraviolet curable silicone composition, and the viscosity of the ink is too low to be suitable for flexographic printing. Absent.

JP-A-2002-240203 Japanese Unexamined Patent Publication No. 2007-23256

The problem to be solved by the present invention is that it does not interfere with the curability of the cationically polymerizable silicone composition used as a release agent, has the physical properties (adhesion, flexibility) of the coating film required for the adhesive label, and has flexography. To provide a cation-polymerizable color ink for flexographic printing having printability, an ink set for an adhesive label of the cation-polymerizable color ink composition for flexo printing and a polymerizable clear ink composition, and a laminate using them. Is.

As a result of diligent studies to solve the above problems, the present inventors have shown the following cationically polymerizable ultraviolet curable color ink composition for flexographic printing, and the cationically polymerizable color ink composition for flexographic printing and clear polymerizable color. We have found that the above problems can be solved by using an ink set for an adhesive label with an ink composition, and have completed the present invention.

That is, the present invention is a cationically polymerizable color ink composition for flexographic printing, which comprises a colorant, a cationic polymerization initiator, and a cationically polymerizable compound.
The cationically polymerizable compound is an epoxy compound (A) having a bisphenol A structure,
Alicyclic epoxy compounds (B) (except when it becomes (A)) and oxetane compounds (C)
) Including
The epoxy compound (A) has a weight average molecular weight of 400 to 2,000.
The present invention relates to a cationically polymerizable color ink composition for flexographic printing, which is substantially free of basic compounds.

Further, the present invention is characterized in that the content of the epoxy compound (A) is 5 to 20% by mass with respect to the total mass of the cationically polymerizable color ink composition for flexographic printing. The present invention relates to a cationically polymerizable color ink composition.

Further, in the present invention, the epoxy equivalent of the alicyclic epoxy compound (B) is 110 to 250.
And
The content of the alicyclic epoxy compound (B) is 10 to 70% by mass with respect to the total mass of the cationically polymerizable color ink composition for flexographic printing. Regarding sex color ink compositions.

Further, in the present invention, the oxetane compound (C) has one oxetane ring and one hydroxyl group in its structure.
The content of the oxetane compound (C) is 10 to 30% by mass based on the total mass of the cation-polymerizable ultraviolet curable color ink composition for flexographic printing. Related to sex color ink compositions.

The present invention also relates to a polymerizable ink set for an adhesive label, which comprises the above-mentioned cationically polymerizable color ink composition for flexographic printing and a polymerizable clear ink composition.

In addition, the present invention further comprises a cationically polymerizable silicone composition as a release agent.
The present invention relates to the above-mentioned polymerizable ink set for an adhesive label, wherein the cationically polymerizable silicone composition contains a cationic polymerization initiator and a polyorganosiloxane compound having an epoxy group.

Further, in the present invention, the above-mentioned polymerizable ink set for an adhesive label is applied to a surface of a base material having an adhesive layer on one side opposite to the adhesive layer, a cationically polymerizable color ink composition for flexographic printing, and a polymerizable clear ink. The present invention relates to a laminate for an adhesive label, which comprises laminating the composition and the cationically polymerizable silicone composition in this order.

According to the present invention, a cation-polymerizable color ink for flexo printing, which does not interfere with the curability of a cationically polymerizable silicone composition used as a release agent, has excellent adhesion to a substrate, and has flexographic printing suitability. It was possible to provide an ink set for an adhesive label of a cationically polymerizable color ink composition for flexographic printing and a polymerizable clear ink composition, and a laminate using them.

Hereinafter, embodiments for carrying out the present invention will be described in detail. The present invention is not limited to the following embodiments, and can be variously modified and implemented within the scope of the gist thereof.

<Conic-polymerizable UV curable color ink for flexographic printing>
One embodiment of the present invention relates to a cationically polymerizable color ink composition for flexographic printing.
The cationically polymerizable color ink composition for flexographic printing includes a colorant, a cationic polymerization initiator, and the like.
A cationically polymerizable color ink composition for flexo printing containing a cationically polymerizable compound, which is an epoxy compound (A) having a weight average molecular weight of 400 to 2,000 and a bisphenol A skeleton as the cationically polymerizable compound, an alicyclic type. It is characterized by containing an epoxy compound (B) (excluding the case where it becomes (A)) and an oxetane compound (C), and substantially no basic compound.

Hereinafter, the cationically polymerizable color ink composition for flexographic printing of the present embodiment (hereinafter, simply "
The components contained in or may be contained in (also referred to as "color ink composition") will be described.

[Colorant]
The cationically polymerizable color ink for flexographic printing in the present invention contains a colorant. As the colorant, at least one of a pigment and a dye can be used. Pigments are preferred from the standpoint of light resistance.
The pigment that can be used in the present invention is not particularly limited, and known pigments can be used. As the pigment, either an inorganic pigment or an organic pigment can be used.

Examples of the above-mentioned inorganic pigments include furnace black, lamp black, and acetylene black.
Examples include carbon blacks such as channel black, iron oxide, and titanium oxide.

Examples of the organic pigments include soluble azo pigments such as β-naphthol type, β-oxynaphthoic acid type, β-oxynaphthoic acid type anilide type, acetoacetate anilide type, and pyrazolone type; β-naphthol type and β-oxynaphthoic acid. Insoluble azo pigments such as anilide, acetoacetate anilide monoazo, acetoacetate anilide disazo, pyrazolone; copper phthalocyanine blue, halogenated (eg, chlorinated or brominated) copper phthalocyanine blue, sulfonated copper phthalocyanine blue, metal Phthalocyanine pigments such as free phthalocyanine; quinacridone, dioxazine, slene (pirantron, antoanthron, indantron, anthrapyrimidine, flavantron, thioindigo, anthraquinone, perinone, perylene, etc.), isoindolinone, Examples thereof include polycyclic pigments such as metal complex type, quinophthalone type, and diketopyrrolopyrrole type, and heterocyclic pigments.
In this specification, barium sulfate, calcium carbonate, aluminum hydroxide and the like, which are extender pigments having no coloring power, are not included in the coloring agent.

More specifically, C.I. I. In terms of color index, black pigments include C.I. I. Pi
gement Black 1, 6, 7, 9, 10, 11, 28, 26, 31 and the like can be mentioned.

As the white pigment, C.I. I. Pigment White 5, 6, 7, 12, 28 and the like.

As the yellow pigment, C.I. I. Pigment Yellow 1, 2, 3, 12, 13,
14, 16, 17, 18, 24, 73, 74, 75, 83, 93, 95, 97, 98, 1
00, 108, 109, 110, 114, 120, 128, 129, 138, 139, 1
74, 150, 151, 154, 155, 167, 180, 185, 213 and the like can be mentioned.

Examples of blue or cyan pigments include C.I. I. Pigment Blue 1, 2, 14, 15
, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62 and the like.

Examples of red or red pigments include C.I. I. Pigment RED 1, 3, 5, 19, 21,
22, 31, 38, 42, 43, 48: 1, 48: 2, 48: 3, 48: 4, 48: 5,
49: 1, 50, 52, 53: 1, 57: 1, 57: 2, 58: 4, 63: 1, 81, 8
1: 1, 81: 2, 81: 3, 81: 4, 83, 90, 104, 108, 112, 114
, 122, 144, 146, 148, 149, 150, 166, 168, 169, 170
, 172, 173, 176, 177, 178, 184, 185, 187, 193, 202
, 209, 214, 242, 254, 255, 264, 266, 269, C.I. I. Pig
Ment Violet 19 and the like can be mentioned.

As a green pigment, C.I. I. Pigment Green 1, 2, 3, 4, 7, 8, 1
Examples thereof include 0, 15, 17, 26, 36, 45 and 50.

As the purple pigment, C.I. I. Pigment Violet 1, 2, 3, 4, 5: 1,
12, 13, 15, 16, 17, 19, 23, 25, 29, 31, 32, 36, 37, 3
9, 42 and the like.
As the orange pigment, C.I. I. Pigment Orange 13, 16, 20,
34, 36, 38, 39, 43, 51, 61, 63, 64, 74 and the like can be mentioned.

In the present invention, the pigment may be used alone or in combination of two or more.

In the present invention, the pigment can be used at any content as long as the desired concentration can be reproduced on the printing paper surface, and is 5 to 30% by mass with respect to the total mass of the color ink composition. It is preferably, more preferably 10 to 25% by mass.

[Cationic polymerization initiator (hereinafter, also referred to as "cation initiator")]
The cationically polymerizable color ink for flexographic printing in the present invention contains a cationic polymerization initiator. A cationic polymerization initiator is a compound capable of releasing a substance that initiates cationic polymerization by receiving energy rays such as light and ultraviolet rays.

In the present invention, the above-mentioned cationic polymerization initiator is not particularly limited, and known ones can be used. Specific examples include acid generators such as aryl sulfonium salt derivatives, aryl iodonium salt derivatives, allen-ion complex derivatives, diazonium salt derivatives, triazines and other halides. Above all, it is preferable to use an aryl sulfonium salt derivative.

The above-mentioned cationic polymerization initiator may be used alone or in combination of two or more.

In the present invention, the content of the cationic polymerization initiator is preferably 0.5 to 30% by mass, more preferably 5 to 20% by mass, based on the total mass of the color ink composition.

In the present invention, it is preferable that the radical polymerization initiator is substantially not contained. In particular, it is preferable that the radical polymerization initiator and the radical polymerization initiation accelerator having an amino group are substantially not contained. Substantially free of the radical polymerization initiator is preferably 1.0% by mass or less, more preferably 0.1% by mass or less, based on the total mass of the color ink composition.

[Cationally polymerizable compound]
The cationically polymerizable color ink for flexo printing in the present invention is an epoxy compound (A) having a weight average molecular weight of 400 to 2,000 and a bisphenol A structure, and an alicyclic epoxy compound (B) as a cationically polymerizable compound. A)) and the oxetane compound (C) are included.

(Epoxy compound having a bisphenol A structure with a weight average molecular weight of 400 to 2,000 (
A))
As the epoxy compound (A) used in the present invention, any known epoxy compound having a weight average molecular weight (hereinafter, also referred to as Mw) of 400 to 2,000 and having a bisphenol A structure may be used. it can. Above all, from the viewpoint of curability, Mw is 600 ~
It is more preferably 1,200.

In the present specification, the weight average molecular weight is calculated from the structural formula when the weight average molecular weight can be specified from the structural formula, and gel permeation chromatography (hereinafter referred to as “gel permeation chromatography”) when the weight average molecular weight cannot be specified from the structural formula. , "GPC").

The specific measurement method of GPC is as follows. A calibration curve was prepared from a standard polystyrene sample using HLC-8020 manufactured by Tosoh Corporation. Tetrahydrofuran was used as the eluent, and three TSKgel SuperHM-M (manufactured by Tosoh Corporation) were used as the column. The measurement was performed at a flow rate of 0.6 ml / min, an injection volume of 10 μl, and a column temperature of 40 ° C.

In the present invention, the content of the epoxy compound (A) having a bisphenol A structure having a weight average molecular weight of 400 to 2,000 is preferably 5 to 20% by mass with respect to the total mass of the color ink composition. More preferably, it is 8 to 15% by mass. When the content is in the above range, the transfer component from the adhesive layer can be suppressed without impairing the curability and flexographic printability of the color ink composition.

Further, the epoxy equivalent of the epoxy compound (A) having a bisphenol A structure having a weight average molecular weight of 400 to 2,000 is 20 from the viewpoint of curability and suppression of component transfer from the adhesive layer.
It is preferably 0 to 1,000, more preferably 400 to 800.

In addition, in this specification, the epoxy equivalent was measured according to JIS K7236.

Specific examples of the epoxy compound (A) having a bisphenol A structure having a weight average molecular weight of 400 to 2,000 include jER1001 (Mw900, epoxy equivalent 450) and jER1002 (Mw1,200, epoxy equivalent 600) manufactured by Mitsubishi Chemical Corporation. ), JER
1003 (Mw1,300, epoxy equivalent 450), jER1004 (Mw1,650,
Epoxy equivalent 875), jER1055 (Mw1,600, epoxy equivalent 800) and the like.

In the present invention, the epoxy compound (A) having a bisphenol A structure having a weight average molecular weight of 400 to 2,000 may be used alone or in combination of two or more.

(Alicyclic epoxy compound (B) (except when it becomes (A)))
In the present invention, the content of the alicyclic epoxy compound (B) is preferably 10 to 70% by mass, more preferably 30 to 50% by mass, based on the total mass of the color ink composition.
Is. When the content is in the above range, the curability of the color ink composition is not impaired.
Flexographic printing suitability can be obtained. In the present invention, the alicyclic epoxy compound is a compound having an epoxy group as a reactive group on the alicyclic skeleton.

In the present invention, known alicyclic epoxy compounds (B) can be used. Specific examples include 3,4-epoxycyclohexylmethyl- (3,4-epoxy) cyclohexanecarboxylate, 2- (3,4-epoxy) cyclohexyl-5,1-spiro (3,4-epoxy) cyclohexyl-meth. -Dioxane, bis (3,4-epoxycyclohexylmethyl) adipate, vinylcyclohexene oxide, 4-vinylepoxycyclohexane, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 3,4-epoxy-6-methyl Cyclohexyl- (3,4-epoxy-6-methyl) cyclohexanecarboxylate, methylenebis (3,4-epoxycyclohexane)
, Dicyclopentadiene diepoxiside, Di (3,4-epoxide cyclohexylmethyl) ether of ethylene glycol, ethylene bis (3,4-epoxide cyclohexanecarboxylate), lactone-modified 3,4-epoxide cyclohexylmethyl- (3,4-) Epoxide) Cyclohexanecarboxylate, limonene monooxide, limonen dioxide and the like. Among them, a compound having two alicyclic epoxy structures is preferable, and 3,4-epoxycyclohexylmethyl- (3,4-epoxy) cyclohexanecarboxylate is more preferable from the viewpoint of curability and flexographic printability.

In the present invention, the alicyclic epoxy compound (B) may be used alone or in combination of two or more.

(Oxetane compound (C))
In the present invention, the content of the oxetane compound (C) is preferably 10 to 30% by mass, more preferably 15 to 25% by mass, based on the total mass of the color ink composition.

As the oxetane compound (C), known compounds can be used. Specifically, as a compound having one oxetane ring, 3-ethyl-3-hydroxymethyloxetane, 3- (meth) allyloxymethyl-3-ethyloxetane, 3-ethyl-3- (4-)
Hydroxybutyloxymethyl) oxetane, (3-ethyl-3-oxetanylmethoxy) methylbenzene, 4-fluoro- [1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, 4-methoxy- [1- (3) -Ethyl-3-oxetanylmethoxy) methyl] benzene, [1- (3-ethyl-3-oxetanylmethoxy) ethyl] phenyl ether, isobutoxymethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyloxyethyl (3-Ethyl-3-oxetanylmethyl) ether, isobornyl (3)
-Ethyl-3-oxetanylmethyl) ether, 2-ethylhexyl (3-ethyl-3-3)
Oxetanylmethyl) ether, ethyldiethylene glycol (3-ethyl-3-oxetanylmethyl) ether, dicyclopentadiene (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenyloxyethyl (3-ethyl-3-oxetanylmethyl)
Ether, dicyclopentenyl (3-ethyl-3-oxetanylmethyl) ether, tetrahydrofurfuryl (3-ethyl-3-oxetanylmethyl) ether, tetrabromophenyl (3-ethyl-3-oxetanylmethyl) ether, 2-tetra Bromophenoxyethyl (3-ethyl-3-oxetanylmethyl) ether, tribromophenyl (3-ethyl-3-oxetanylmethyl) ether, 2-tribromophenoxyethyl (3-ethyl-3-oxetanylmethyl) ether, 2- Hydroxyethyl (3-ethyl-3-oxetanylmethyl) ether, 2-hydroxypropyl (3-ethyl-3-oxetanylmethyl) ether, butoxyethyl (3-ethyl-3-oxetanylmethyl) ether, pentachlorophenyl (3-ethyl) -3-Occetanylmethyl) ether, pentabromophenyl (3-ethyl-3-oxetanylmethyl) ether, Bornil (3-ethyl-3-3)
Examples of the compound having two or more oxetane rings include oxetanylmethyl) ether and the like, 3,7-bis (3-oxetanyl) -5-oxa-nonane, 3,3'-(1,3-).
(2-Methylenyl) Propanediylbis (oxymethylene)) Bis- (3-ethyloxetane), 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene,
1,2-Bis [(3-ethyl-3-oxetanylmethoxy) methyl] ethane, 1,3-bis [(3-ethyl-3-oxetanylmethoxy) methyl] propane, ethylene glycol bis (3-ethyl-3-3) Oxetanylmethyl) ether, dicyclopentenylbis (3-
Ethyl-3-oxetanylmethyl) ether, triethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, tetraethylene glycol bis (3-ethyl-3)
-Oxetanylmethyl) ether, tricyclodecandyldimethylene (3-ethyl-3)
-Oxetanylmethyl) ether, trimethylolpropane tris (3-ethyl-3-oxetanylmethyl) ether, 1,4-bis (3-ethyl-3-oxetanylmethoxy)
Butane, 1,6-bis (3-ethyl-3-oxetanylmethoxy) hexane, pentaerythritol tris (3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether, polyethylene Glycolbis (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol hexaxe (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol pentax (3-ethyl-3-oxetanylmethyl) ether, dipenta Elysylitol tetrakis (3-ethyl-3-oxetanylmethyl) ether, caprolactone-modified dipentaerythritol hexaxe (3-ethyl-3-oxetanylmethyl) ether, caprolactone-modified dipentaerythritol pentax (3-ethyl-3-oxetanylmethyl) Ether, ditrimethylolpropane tetrakis (3-ethyl-3-oxetanylmethyl) ether, EO-modified bisphenol A bis (3-ethyl-3-oxetanylmethyl)
Ether, PO-modified bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, EO-modified hydrogenated bisphenol A bis (3-ethyl-3-oxetanylmethyl) ether, PO-modified hydrogenated bisphenol A bis (3-ethyl-) Examples thereof include 3-oxetanylmethyl) ether and EO-modified bisphenol F (3-ethyl-3-oxetanylmethyl) ether. Of these, a compound having one oxetane ring is preferable because of the flexibility of the coating film.
Further, from the viewpoint of adhesion to the substrate, a compound having one oxetane ring and one hydroxyl group is preferable.

(Other polymerizable compounds)
The polymerizable compound other than the above (hereinafter, referred to as “other polymerizable compound”) is not particularly limited, and other polymerizable compounds may be used as long as the effect of the present invention is not deteriorated.
Specific examples thereof include compounds having a polymerizable group such as a (meth) acryloyl group, an allyl group, a vinyl group, a vinyl ether group, and an internal double bond group (maleic acid, etc.) in the molecule. Of these, compounds having a vinyl group and a vinyl ether group are preferable from the viewpoint of cationic polymerization.

[Other ingredients]
In the present invention, the color ink composition is an extender pigment, a resin, a leveling agent, an antistatic agent, a surfactant, a surface tension adjusting agent, a defoaming agent, a polymerization inhibitor, an ultraviolet ray, as long as the effect of the present invention is not deteriorated. Absorbents, antioxidants and the like can be added as needed.

In the present invention, it is preferable that the color ink composition does not substantially contain a basic compound. The term "substantially free" means that the color ink composition is preferably 1.0% by mass or less, more preferably 0.1% by mass or less, based on the total mass of the color ink composition. By not containing the basic compound in the color ink composition, the curability of the cationically polymerizable clear ink composition of the clear layer printed on the ink layer and the cationically polymerizable silicone composition of the release layer is improved. , Adhesion is also improved.

In the present specification, the basic compound includes both an organic basic compound and an inorganic basic compound. The organic basic compound is a compound having a higher basicity than phenol, and examples thereof include nitrogen-containing organic compounds and organic amines.

Specific examples of organic basic compounds include decylamine, dodecylamine, N, N-dimethyldodecylamine, stearylamine, cetylamine, benzylpiperidine, N, N-dimethylcyclohyxylamine, mono, di, or triethanolamine, amino. Propanol, aminobutanol, aminohexanol, dimethylaminohexanol, morpholin, aminoethylmorpholin, aminopropylmorpholin, aminoethylpiperazin, aminoethylpyrrolidin, bis (hydroxyethyl) piperazine, aminopropylpyrrolidinone, aminoethoxyethanol, dimethylaminoethylmorpholin, Phenylmorpholin, 1,3-bis [1- (2-hydroxyethyl) -4-piperidyl] propane, glamin, 1- (2-phenethyl) -4-piperidone, ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylene Diamine, aniline, N, N-diethylaniline, dodecylaniline, aminobiphenyl, aminophenol, 4-aminoacetanilide, aminoacetophenone, aminobenzamide, aminobenzanilide, aminobenzophenone, dimethylaminomethylthiophene, dimethylaminophenethyl alcohol,
Copolymers of polyethyleneimine, polyarylamine, polyvinylpyridine, N, N-dimethylaminoethyl methacrylate and methacrylate esters (eg butyl methacrylate), N, N-diethylaminoethyl methacrylate and acrylic acid esters (eg ethyl acrylate) Copolymers, dimethylaminomethylstyrene and styrene copolymers, 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinethanol and 1,
Condensation polymer of 4-butanedioic acid, guanidine, 1,1-dimethylguanidine, 1,1,3
, 3,-Tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2- (aminomethyl) pyridine, 2- Amino-3-methylpyridine, 2
-Amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazin, N- (2-) Aminoethyl) piperazin, N- (2-aminoethyl)
Piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidin, 1- (2-aminoethyl) pyrrolidine, pyrazole,
3-Amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6 -Dihydroxypyrimidine, 2-pyrazolin, 3-pyrazolin,
N-aminomorpholine, N- (2-aminoethyl) morpholine, 1,5-diazabicyclo [4.3.0] nona-5-ene, 1,8-diazabicyclo [5.4.0] undeca-
7-ene, 1,4-diazabicyclo [2.2.2] octane, 2,4,5-triphenylimidazole, N-methylmorpholine, N-ethylmorpholine, N-hydroxyethylmorpholine, N-benzylmorpholine, cyclohexyl Morpholine ethylthiourea (CH)
Examples thereof include tertiary morpholine derivatives such as METU).

In addition, 2-benzyl-2- (dimethylamino) -1 used as a radical polymerization initiator
-(4-Morpholine phenyl) -1-butanone, 2- (dimethylamino) -2-[(4-4-morpholinophenyl)
Methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone and the like are also mentioned as organic basic compounds.

In addition, triethanolamine, p-dimethylaminobenzoic acid ethyl ester, p-formyldimethylaniline, p-methylthiodimethylaniline and the like used as radical polymerization accelerators are also mentioned as organic basic compounds.

Further, a known polymer dispersant having a basic polar group and an amine value used as a pigment dispersant can also be mentioned as an organic basic compound. Specifically, Dis made by Big Chemie
perBYK®-161 (amine value 11 mgKOH / g), DisperBY
K-162 (amine value 13 mgKOH / g), DisperBYK-163 (amine value 1)
0 mgKOH / g), DisperBYK-164 (amine value 18 mgKOH / g), D
isperBYK-166 (amine value 20 mgKOH / g), DisperBYK-16
7 (amine value 13 mgKOH / g, oxidation 0 mgKOH / g), DisperBYK-16
8 (amine value 10 mgKOH / g, oxidation 0 mgKOH / g), Solsperse (registered trademark) 24000 (amine value 47 mgKOH / g) manufactured by Lubrisol, Solsperse 320
Examples thereof include 00 (amine value 27.1 mgKOH / g) and Ajinomoto Finetech Co., Ltd. Ajispar (registered trademark) PB822 (amine value 17 mgKOH / g).

[Physical characteristics of cationically polymerizable color ink composition for flexographic printing]
(viscosity)
In the present invention, the viscosity of the color ink composition at 25 ° C. is preferably 200.
It is ~ 1,000 mPa · s, more preferably 300 to 800 mPa · s. 25
When the viscosity at ℃ is within the above range, troubles such as transfer failure due to the increase in viscosity can be reduced in the process of transferring the ink composition in the order of anilox roll, plate, and recording medium, and good flexographic printability is obtained. can get. The viscosity is E-type viscometer (T of Toki Sangyo Co., Ltd.)
It can be measured by reading the viscosity at a rotation speed of 100 rpm in an environment of 25 ° C. using a VE-25 type viscometer, type E).

<Ink set for adhesive label>
The adhesive label ink set in the present invention includes the above-mentioned cationically polymerizable color ink composition for flexographic printing and a polymerizable clear ink composition. By using the ink set, it is possible to suppress the transfer component from the adhesive layer and suppress the deterioration of the adhesion between the base material and the color ink layer over time.

<Polymerizable clear ink composition>
In the present embodiment, either a cationically polymerizable clear ink composition or a radically polymerizable clear ink composition can be used. Hereinafter, the components contained in or may be contained in the polymerizable clear ink composition of the present embodiment (hereinafter, also referred to as clear ink) will be described.

[Cationopolymerizable clear ink composition]
The cationically polymerizable clear ink composition is characterized by containing a cationic polymerization initiator and a cationically polymerizable compound, and substantially free of a colorant. The term “substantially free” means that the amount is preferably 1.0% by mass or less, more preferably 0.1% by mass or less, based on the total mass of the clear ink composition.

As the cationic polymerization initiator, the cationic polymerization initiator exemplified as being contained in the above-mentioned color ink composition can be used. Above all, it is preferable to use an aryl sulfonium salt derivative.

In the present invention, the content of the cationic polymerization initiator is the content of the cationic polymerization initiator contained in the color ink composition from the viewpoint of the curability of the film and the adhesion between the color ink layer and the clear ink layer. It is preferably 0.5 to 30% by mass, and 5 to 20% by mass.
More preferably, it is by mass.

As the cationically polymerizable compound, the cationically polymerizable compound exemplified as being contained in the above-mentioned color ink composition can be used. Among them, from the viewpoint of suppressing the transfer component from the adhesive layer, it is preferable to contain 3,4-epoxycyclohexylmethyl-3', 4'-epoxycyclohexanecarboxylate and 3-ethyl-3-hydroxymethyloxetane.

In the present invention, the above-mentioned cationic polymerization clear ink composition is a resin, a leveling agent, an antistatic agent, a surfactant, a defoaming agent, a polymerization inhibitor, an ultraviolet absorber, and an antioxidant as long as the effect of the present invention is not deteriorated. Agents and the like can be added as needed.

In the present invention, the cationically polymerizable clear ink composition may contain other polymerizable compounds and other components exemplified as those contained in the above-mentioned color ink composition as necessary, as long as the effects of the present invention are not reduced. Can be added.

In the present invention, it is preferable that the cationically polymerizable clear ink composition does not substantially contain a basic compound like the above-mentioned color ink composition. The term "substantially free" is preferably 1.0% by mass or less, more preferably 0.1% by mass or less, based on the total mass of the cationically polymerizable clear ink composition.

The basic compound is the same as the basic compound exemplified as being substantially not contained in the above-mentioned color ink composition.

[Radical polymerizable clear ink composition]
The radically polymerizable clear ink composition is characterized by containing a radical polymerization initiator and a radically polymerizable compound, and substantially free of a colorant and a basic compound. The term “substantially free” means that the amount is preferably 1.0% by mass or less, more preferably 0.1% by mass or less, based on the total mass of the clear ink composition.

The radical polymerization initiator is not particularly limited, and a known photopolymerization initiator can be used. Specific examples include benzophenone compounds, dialkoxyacetophenone compounds, α-hydroxyalkylphenone compounds, acylphosphine oxide compounds, thioxanthone compounds and the like. Further, the radical polymerization initiator may be used alone or in combination of two or more.

Examples of the benzophenone compound include benzophenone, 4-methylbenzophenone, and the like.
Examples thereof include 4-phenylbenzophenone and [4- (methylphenylthio) phenyl] -phenylmethanone.

Examples of the α-hydroxyalkylphenone compound include 1-hydroxy-cyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propane-1-one, and 1- [4- (2-hydroxymethoxy) -phenyl. ] -2-Hydroxy-2-methyl-
Examples thereof include 1-propane-1-one and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl] -2-methyl-propane-1-one. ..

Examples of the above-mentioned acylphosphine oxide compounds include diphenylacylphenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide. Can be mentioned.

Examples of the thioxanthone-based compound include 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, and 2,4-diethylthioxanthone.

The content of the radical polymerization initiator is preferably 1 to 25% by mass, more preferably 5 to 20% by mass, based on the total mass of the radically polymerizable clear ink composition.

The radically polymerizable compound is not particularly limited, and a known radically polymerizable compound can be used. The polymerizable compound that can be used in the present invention is not particularly limited as long as it is a compound having one or more ethylenically unsaturated bonds in the molecule as a radically polymerizable group, and is in any form of a monomer, an oligomer, or a polymer. Also includes. Further, the radically polymerizable compound may be used alone or in combination of two or more.

Examples of the radically polymerizable compound include 2-ethylhexyl (meth) acrylate and 2-.
Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, β-carboxyethyl (meth) acrylate, 4-tert-butylcyclohexanol (meth) acrylate, tetrahydrofurfuryl acrylate, alkoxylated tetrahydrofurfuryl acrylate, caprolactone (Meta) Acrylate, Lauryl (Meta)
Acrylate, stearyl (meth) acrylate, isoamyl (meth) acrylate, 2
-Phenoxyethyl (meth) acrylate, isodecyl (meth) acrylate, 3,3
5-trimethylcyclohexanol (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, norbornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (oxyethyl) (meth)
Acrylate, 1,4-Cyclohexanedimethanol (meth) acrylate, cyclic trimethylolpropane formal (meth) acrylate, benzyl (meth) acrylate, E
O-modified (2) Monofunctional (meth) having one (meth) acryloyl group in the molecule such as nonylphenol acrylate, 2-methyl-2-ethyl-1,3-dioxolane-4-yl) methyl acrylate, acryloylmorpholin, etc. ) Acrylate monomer,
N-vinylcarbazole, 1-vinylimidazole, N-vinyl-2-pyrrolidone, N-
Monofunctional vinyl monomers having one vinyl group in the molecule, such as vinyl caprolactam and N-vinylformamide,
1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, 1
, 6-Hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 1,2-dodecanediol di (meth) acrylate, neopentyl glycol Di (meth) acrylate, polyethylene glycol (200) Di (meth) acrylate, polyethylene glycol (300)
) Di (meth) acrylate, polyethylene glycol (400) di (meth) acrylate, polyethylene glycol (600) di (meth) acrylate, neopentyl glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, Tripropylene glycol di (meth) acrylate, EO modified (2) 1,6-
Hexanediol di (meth) acrylate, PO modified (2) Neopentyl glycol di (
Meta) acrylate, (neopentyl glycol modified) trimethylolpropane di (meth) acrylate, dimethyloltricyclodecandi (meth) acrylate, EO modified (4)
) Bisphenol A di (meth) acrylate, PO modified (4) Bisphenol A di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, dimethylol-
A bifunctional (meth) acrylate monomer having two (meth) acryloyl groups in the molecule, such as tricyclodecanedi (meth) acrylate and dicyclopentanyldi (meth) acrylate,
Trimethylolpropane tri (meth) acrylate, EO modified (3) trimethylolpropane tri (meth) acrylate, PO modified (3) trimethylolpropane tri (meth)
Acrylate, ε-caprolactone-modified tris (2-acryloxyethyl) isocyanurate, tri (meth) ethoxylated isocyanurate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, pentaerythritol tri (meth)
A trifunctional (meth) acrylate monomer having three (meth) acryloyl groups in a molecule such as acrylate,
A tetrafunctional (meth) acrylate monomer having four acryloyl groups in the molecule, such as pentaerythritol tetra (meth) acrylate and ditrimethylolpropane tetra (meth) acrylate.
Dipentaerythritol A pentafunctional (meth) acrylate monomer having five (meth) acryloyl groups in the molecule, such as penta (meth) acrylate.
Examples thereof include a hexafunctional (meth) acrylate monomer having six (meth) acryloyl groups in the molecule such as dipentaerythritol hexa (meth) acrylate.
In addition, in this specification, "(meth) acrylate" means either acrylate and / or methacrylate.

In the present invention, the radically polymerizable clear ink composition is an extender pigment, a resin, a leveling agent, an antistatic agent, a surfactant, a defoaming agent, a polymerization inhibitor, and an ultraviolet absorber as long as the effect of the present invention is not deteriorated. Agents, antioxidants and the like can be added as needed.

In the present invention, it is preferable that the radically polymerizable clear ink composition does not substantially contain a basic compound like the above-mentioned color ink composition. The term "substantially free" means that the amount is preferably 0.5% by mass or less, more preferably 0.1% by mass or less, based on the total mass of the radically polymerizable clear ink composition.

[Physical characteristics of polymerizable clear ink composition]
(viscosity)
In the present invention, the viscosity of the polymerizable clear ink composition at 25 ° C. is 100 to 80.
It is 0 mPa · s, more preferably 200 to 500 mPa · s. When the viscosity at 25 ° C. is within the above range, troubles such as leveling defects can be reduced in the process of transferring the ink composition in the order of anilox roll, plate, and recording medium, and a good printed matter can be obtained. The viscosity is determined by E-type viscometer (TVE-25 type viscometer manufactured by Toki Sangyo Co., Ltd., type).
It can be measured by reading the viscosity at a rotation speed of 100 rpm in an environment of 25 ° C. using E).

The adhesive label ink set in the present invention preferably further has a release agent.

<Cationopolymerizable silicone composition>
In the present invention, the release agent is not particularly limited, and a known release agent can be used. Among them, a cationically polymerizable silicone composition containing a cationic polymerization initiator and a polyorganosiloxane compound having an epoxy group is preferable from the viewpoint of controlling productivity and peeling performance.

Examples of the cationically polymerizable silicone composition include UVPOLY200, UVPOLY201, and UVPOLY215 of the Silicone lease series manufactured by Arakawa Chemical Industry Co., Ltd., and X-62-7622, X-62-7660, and X-62- manufactured by Shin-Etsu Chemical Co., Ltd. 7655 and the like can be mentioned.

<Laminate for adhesive label>
In the laminate for an adhesive label in the present invention, the color ink composition is printed on the other side of a substrate having an adhesive layer on one side by a flexographic printing method and cured. After curing, the clear ink composition is printed and cured on it, and further, the cationically polymerizable silicone composition is printed and cured as a release agent. As a result, it is possible to obtain a laminate for an adhesive label that suppresses the transfer component from the adhesive layer and suppresses the deterioration of the adhesion between the base material and the color ink layer over time.

As the recording medium, thermal paper (thermal paper) can be used. In particular,
Examples thereof include GS80, HE90, GG50 manufactured by Oji Paper, 150LA-1, 150LHB manufactured by Ricoh, and the like.

In the present invention, the method for curing the color ink composition, the clear ink composition, and the cationically polymerizable silicone composition is not particularly limited, and known methods can be used. For example, it can be cured by irradiating with α-rays, γ-rays, electron beams, X-rays, ultraviolet rays, visible light, infrared light and the like. Of these, ultraviolet rays and electron beams are preferable, and ultraviolet rays are more preferable. The peak wavelength of ultraviolet rays is preferably 200 to 600 nm, more preferably 250 to 420 nm.

The ultraviolet source is not particularly limited, and a known source can be used. In particular,
Mercury lamps, xenon lamps, metal hydride lamps, ultraviolet light emitting diodes (UV)
-LED), LED (light emitting diode) such as ultraviolet laser diode (UV-LD), gas / solid-state laser, and the like.

The coating film thickness of the color ink composition and the clear ink composition is preferably 1 to 20 μm, more preferably 5 μm to 10 μm.

The present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited thereto. In Examples and Comparative Examples, "parts" and "%" represent "parts by mass" and "% by mass", respectively.

[Preparation of cationically polymerizable color ink composition for flexographic printing]
Color ink 1
5 parts of JER1001 as the cationically polymerizable compound (A) and 10 parts of CER4221 as the cationically polymerizable compound (B) were mixed, and JER1001 was dissolved by heating with stirring. After that, 35 parts of CER4221 and PIGMENT YE as a colorant
Add 15 parts of LLOW 1453T and disperse with 3 rolls so that the maximum particle size is 20 μm or less. Then, as a cationically polymerizable compound (C), add 20 parts of OXT-101 and a cationic polymerization initiator. As a result, 15 parts of AT-6992 was added and stirred to prepare a cationically polymerizable color ink composition.

Cationic polymerizable color ink 2-ink 24
Inks 2 and 24 were obtained in the same manner as ink 1, except that the raw materials and amounts shown in Table 1 were changed.

[Preparation of radically polymerizable color ink composition for flexographic printing]
Ink 24
15 parts of Viscoat 230D as a radical polymerization compound and LION as a colorant
15 parts of OL YELLOW TT1842 and Azisper PB822 as a pigment dispersant
3 parts, 5 parts of Omnirad 369 as a radical polymerization initiator, and Omnirad
Add 7 parts of TPO and disperse with 3 rolls so that the maximum particle size is 20 μm or less, then add 25 parts of MIRAMER M3130 and 20 parts of MIRAMER M600 and stir to make a radically polymerizable color. An ink composition was prepared.

Radical Polymerizable Color Ink 24 to Ink 26
Inks 24 to 26 were obtained in the same manner as ink 24, except that the raw materials and amounts shown in Table 1 were changed.

In addition, the blank indicates that it is not mixed.

[Preparation of cationically polymerizable clear ink composition]
Clear 1
As a cationically polymerizable compound, 10 parts of jER1001 and 5 of celoxide 2021P.
0 part and 20 parts of OXT-101 were added, and jER1001 was heated and dissolved with stirring. After that, 5 parts of AT-6992 as a cationic polymerization initiator and FLEX as another resin.
10 parts of OREZ-188 and 5 parts of Fineoxocol 180 as a surface tension adjuster were added and stirred to prepare a cationically polymerizable clear ink composition.

[Preparation of radically polymerizable clear ink composition]
Clear 2
As a radically polymerizable compound, 30 parts of MIRAMER M600, Sartomer SR3
Add 30 copies of 06, 25 copies of Photomer 4028, and then 5 of Omnirad 4MBZ.
5 parts of Omnirad 481 as a surface tension adjuster, Fine Oxyacid 180
Was added, and the mixture was heated and stirred to prepare a radically polymerizable clear ink composition.

Clear 3
Clear 3 was obtained in the same manner as in Clear 2 except that the raw materials and amounts shown in Table 2 were changed.

The abbreviations in Tables 1 and 2 are as follows.
[Colorant]
Pigment Yellow 1453T: manufactured by Sanyo Dye Co., Ltd., C.I. I. Pigm
ent Yellow 14

[Cationic polymerization initiator]
-AT-6992: Made by ACETO

[Cationally polymerizable compound]
-JER828: Mitsubishi Chemical Corporation, bisphenol A type epoxy compound, Mw3
70, epoxy equivalent 120
-JER834: Mitsubishi Chemical Corporation, bisphenol A type epoxy compound, Mw4
70, epoxy equivalent 230
・ JER1001: Mitsubishi Chemical Corporation, bisphenol A type epoxy compound, Mw
900, epoxy equivalent 450
-JER1002: Mitsubishi Chemical Corporation, bisphenol A type epoxy compound, Mw
1200, epoxy equivalent 875
-JER1004: Mitsubishi Chemical Corporation, bisphenol A type epoxy compound, Mw
1650, epoxy equivalent 875
-JER1007: Mitsubishi Chemical Corporation, bisphenol A type epoxy compound, Mw
2900, epoxy equivalent 1750
-TTA15: Sun Chemical Co., Ltd., 3,4-epoxycyclohexylmethyl methacrylate-CER4221: Achiewell, 3,4-epoxycyclohexylmethyl-
(3,4-Epoxide) Cyclohexanecarboxylate, TTA26: Sun Chemical Co., Ltd., Bis (3,4-Epoxide, Cyclohexylmethyl) Adipate, Epolite 1600: Kyoeisha Co., Ltd. -101: Toa Synthetic Co., Ltd., 3-Ethyl-3-hydroxymethyloxetane, OXT-212: Toa Synthetic Co., Ltd., 2-Ethylhexyl oxetane, OXT-121: Toa Synthetic Co., Ltd., Xylenebis oxetane, OXT- 221: Toa Synthetic Co., Ltd., 3-ethyl-3 {[(3-ethyloxetane-
3-Il) methoxy] methyl} oxetane

[Radical polymerization initiator]
Omnirad 369: manufactured by iGM RESINS, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1
-Omnirad TPO: iGM RESINS, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide-Omnirad4MBZ: iGM RESINS, 4-methylbenzophenone dalocure 1173: BASF, 2-hydroxy-2-methyl-1 -Phenyl-1
-Propanone Omnirad 481: 1-Hydroxycyclohexylphenyl ketone manufactured by iGM RESINS

[Radical polymerizable compound]
-Viscoat 230D: Acrylic ester multimer ester of 1,6-hexanediol manufactured by Osaka Organic Chemical Industry Co., Ltd.-Miramer M3130: Miwon Specialty Chemical
Co. , Ltd, EO-modified (3) Trimethylolpropane Triacrylate-Miramer M600: Miwon Specialty Chemical C
o. , Ltd, Dipentaerythritol Hexaacrylate Photomer 4028: iGM RESINS, EO Modified Bisphenol A Diacrylate Sartomer SR306: Sartomer, Tripropylene Glycol Diacrylate Evecryl 8415: Ornex, Urethane Acrylate

[Basic compound]
-Ajisper PB822: Ajinomoto Phi Chemical Co., Ltd., basic pigment dispersant, amine value 17 mgKOH / g

[resin]
-Beam set 271: Arakawa Chemical Co., Ltd., amine-modified acrylate polymer-FLEXOREZ-188: Kusumoto Kasei Co., Ltd., polyester polyol

[Surface tension adjuster]
-Fineoxocol 180: Isooctadecanol manufactured by Nissan Chemical Industries, Ltd.

[How to create a test sample]
Test sample 1
The obtained color ink composition was applied to a thermal paper (150LA manufactured by Ricoh Co., Ltd.) as a base material, using an Anilox roller having a number of lines of 800 LPI and a cell volume of 3.72 cm ³ / m ^{2 and} a flexiproof machine. Was printed and then cured with a conveyor speed of 50 m / min and an air-cooled mercury lamp (under the conditions of an output of 160 w / cm ² ). Then, the obtained clear ink 1 was printed on the color ink layer using an Anilox roller having a line number of 400 LPI and a cell volume of 9.48 cm ³ / m ² , and then a conveyor speed of 50 m / min and an air-cooled mercury lamp lamp (air-cooled mercury lamp lamp). It was cured at an output of 160 w / cm ² ). Furthermore, on the clear layer, the number of lines is 400 LPI,
After printing Silicone's UVPOLY215 (manufactured by Arakawa Chemical Co., Ltd.) as a release agent using an Anilox roller with a cell volume of 9.48 cm ³ / m ² , a conveyor speed of 50 m / min and an air-cooled mercury lamp lamp (condition of output 160 w / cm ² ). It was cured with. Then, a test sample 1 in which a base material, a color ink layer, a clear ink layer, and a release layer were laminated in this order was obtained.

Test samples 2-26
Test samples 2 to 26 were obtained in the same manner as in sample 1 except that the color inks and clear inks shown in Table 3 were changed.

[Curability of release agent]
The peeled layer surface of the test samples 1 to 29 prepared by the above method immediately after curing was touched with a finger and evaluated according to the following criteria. A level of 3 or higher is evaluated as having no practical problem.
5: Completely non-sticky.
4: Almost no stickiness.
3: Almost no stickiness, but slightly sticky.
2: Somewhat sticky.
1: There is stickiness.

[Adhesion to the substrate immediately after curing]
A cellophane tape peeling test was performed between the printed layer surface of the test samples 1 to 29 prepared by the above method and the base material, and the evaluation was made according to the following criteria. A level of 3 or higher is evaluated as having no practical problem.
5: No peeling at all.
4: About 5% of the adhesive surface is peeled off.
3: About 15% of the adhesive surface is peeled off.
2: 50% or more of the adhesive surface is peeled off.
1: All peel off.

[Removability over time]
The printed layer surface of the test samples 1 to 29 prepared by the above method and the adhesive layer surface of the thermal paper coated with the adhesive (Cybinol manufactured by Saiden Chemical Co., Ltd.) are overlapped and a load of 10 kg per square centimeter is applied. It was allowed to stand at 60 ° C. for 10 days. And 10 days later, 25 ° C
The printed surface and the adhesive layer surface were peeled off, and the state of the printed surface was visually evaluated according to the following criteria. A level of 3 or higher is evaluated as having no practical problem.
5: Good peelability without affecting the printed surface.
4: There is no effect on the printed surface, but a slight peeling resistance is felt.
3: There is no effect on the printed surface, but peeling resistance is felt.
2: The printed surface and the adhesive surface adhere to each other, and the printed surface is peeled off in an area of less than 50%.
1: The printed surface and the adhesive surface adhere to each other, and the printed surface is peeled off in an area of 50% or more.

[Flexibility]
The test samples 1 to 29 obtained by the above method are bent back by 180 ° so that the peeling layer is on the inside, and further bent by 180 ° so that the peeling layer is on the outside, and the state of the printed layer in the bent portion is checked. , Visual evaluation was performed according to the following criteria. A level of 3 or higher is evaluated as having no practical problem.
5: There is no effect on the printed surface and there is no cracking of the film.
4: There is no effect on the printed surface, but slight cracks are confirmed.
3: There is no effect on the printed surface, but cracks in the film are slightly confirmed.
2: The printed surface is slightly cracked, and the base material can be confirmed.
1: The printed surface is cracked and the base material can be confirmed.

Claims (7)

A cationically polymerizable color ink composition for flexographic printing, which comprises a colorant, a cationic polymerization initiator, and a cationically polymerizable compound.
The cationically polymerizable compound is an epoxy compound (A) having a bisphenol A structure,
Alicyclic epoxy compounds (B) (except when it becomes (A)) and oxetane compounds (C)
) Including
The epoxy compound (A) has a weight average molecular weight of 400 to 2,000.
A cationically polymerizable color ink composition for flexographic printing, which is substantially free of basic compounds. The flexo printing cation according to claim 1, wherein the content of the epoxy compound (A) is 5 to 20% by mass with respect to the total mass of the cation-polymerizable color ink composition for flexographic printing. Polymerizable color ink composition. The epoxy equivalent of the alicyclic epoxy compound (B) is 110 to 250.
According to claim 1 or 2, the content of the alicyclic epoxy compound (B) is 10 to 70% by mass with respect to the total mass of the cationically polymerizable color ink composition for flexographic printing. The cationically polymerizable color ink composition for flexographic printing described. The oxetane compound (C) has one oxetane ring and one hydroxyl group in its structure.
Any one of claims 1 to 3, wherein the content of the oxetane compound (C) is 10 to 30% by mass with respect to the total mass of the cationically polymerizable color ink composition for flexographic printing. The cationically polymerizable color ink composition for flexographic printing according to the section. A polymerizable ink set for an adhesive label, which comprises the cationically polymerizable color ink composition for flexographic printing according to any one of claims 1 to 4 and the polymerizable clear ink composition. Further, as a release agent, a cationically polymerizable silicone composition is provided.
The polymerizable ink set for an adhesive label according to claim 5, wherein the cationically polymerizable silicone composition contains a cationic polymerization initiator and a polyorganosiloxane compound having an epoxy group. The polymerizable ink set for an adhesive label according to claim 6, a cationically polymerizable color ink composition for flexographic printing, and a polymerizable clear ink composition on the surface of the base material having an adhesive layer on one side opposite to the adhesive layer. , A laminate for an adhesive label, characterized in that the cationically polymerizable silicone composition is laminated in this order.