JP2013043935A - Inkjet ink composition, inkjet recording method, decorative sheet, and in-mold forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inkjet ink composition which excels in the film hardness of an image, stretchability at high temperatures, and ink flow resistance.SOLUTION: The inkjet ink composition includes a resin having an urethane bond in the main chain and an ethylenically unsaturated group and a polysiloxane structure in the side chain and/or at the end and a compound represented by formula (B) [wherein Rand Rare each hydrogen or a methyl group; Xand Xare each a single bond, an ether bond, an oxyalkylene group or an ester bond; Yand Yare each a single bond, a methylene group, an ethyleneoxy group, a propyleneoxy group or the like; and Z is a group represented by formula (Z-1), (Z-2a) or (Z-2b)].

Description

  The present invention relates to an inkjet ink composition, an inkjet recording method, a decorative sheet, and an in-mold molding method.

As an image recording method for forming an image on a recording medium such as paper based on an image data signal, there are an electrophotographic method, a sublimation type and a melt type thermal transfer method, an ink jet method and the like.
The ink jet method is an ink composition because the printing apparatus is inexpensive and does not require a plate at the time of printing, and the ink composition is ejected only on the required image portion to form an image directly on the recording medium. Can be used efficiently, especially in the case of small lot production. Furthermore, it has low noise and is excellent as an image recording method, and has attracted attention in recent years.
In particular, an ink-jet ink composition that can be cured by irradiation with radiation such as ultraviolet rays (a radiation-curable ink composition for inkjet recording) cures most of the components of the ink composition upon irradiation with radiation such as ultraviolet rays. This method is superior in that it can be printed on various recording media because it is excellent in drying properties and is less likely to bleed as compared with the ink-based ink composition.

  The radiation curable ink composition has various advantages because it is imparted with high curability by irradiation with actinic radiation, and the cured film of the obtained image (printed product) has high flexibility, extensibility, and adhesion to the substrate. By having such properties, impact resistance, blocking resistance, etc., there are merits that the printed matter can be displayed and stored for a long period of time in various environments while maintaining high image quality, and handling of the printed matter becomes easy. Examples of these ink-jet ink compositions include those described in Patent Documents 1 and 2.

  Also, in the field of three-dimensional decorative molding such as in-mold lamination and in-mold decoration, radiation-curable ink compositions have been used because decoration by an ink jet recording method is simple for reducing the number of copies / short delivery time. ing.

JP 2010-222385 A JP 2010-235697 A

  An object of the present invention is to provide an ink jet ink composition excellent in film hardness of the obtained image, stretchability at high temperature, and ink flow resistance, an ink jet recording method using the ink jet ink composition, and an excellent punching processability. It is to provide a decorative sheet and an in-mold forming method.

The above-described problems of the present invention have been solved by means described in the following <1>, <18>, <20>, and <21>. It is described below together with <2> to <17> and <19> which are preferred embodiments.
<1> (Component A) Resin having a urethane bond in the main chain and having an ethylenically unsaturated group and a polysiloxane structure in the side chain and / or terminal, and (Component B) represented by the formula (B) An ink-jet ink composition comprising:

（式（Ｂ）中、Ｒ¹及びＲ²はそれぞれ独立に、水素原子又はメチル基を表し、Ｘ¹及びＸ²はそれぞれ独立に、単結合、エーテル結合、オキシアルキレン基又はエステル結合を表し、Ｙ¹及びＹ²はそれぞれ独立に、単結合、メチレン基、エチレンオキシ基、プロピレンオキシ基、ポリ（エチレンオキシ）基又はポリ（プロピレンオキシ）基を表し、Ｚは式（Ｚ−１）で表される基、式（Ｚ−２ａ）で表される基、式（Ｚ−２ｂ）で表される基、又は、式（Ｚ−２ａ）で表される基及び式（Ｚ−２ｂ）で表される基を２以上組み合わせた基を表す。）

(In the formula (B), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, X ¹ and X ² each independently represent a single bond, an ether bond, an oxyalkylene group or an ester bond, Y ¹ and Y ² each independently represent a single bond, a methylene group, an ethyleneoxy group, a propyleneoxy group, a poly (ethyleneoxy) group or a poly (propyleneoxy) group, and Z is represented by the formula (Z-1). Group represented by formula (Z-2a), group represented by formula (Z-2b), or group represented by formula (Z-2a) and formula (Z-2b). Represents a group in which two or more groups to be combined are combined.)

（式（Ｚ−１）、式（Ｚ−２ａ）及び式（Ｚ−２ｂ）中、波線部分は式（Ｂ）中のＹ¹及びＹ²との結合位置を表し、ｒはそれぞれ独立に１以上の整数を表す。）

(In Formula (Z-1), Formula (Z-2a) and Formula (Z-2b), the wavy line part represents the bonding position with Y ¹ and Y ^{2 in} Formula (B), and r is independently 1 (It represents the integer above.)

<2> The inkjet ink composition according to <1>, wherein the content of component B is 0.5 to 10% by weight based on the total weight of the ink composition;
<3> (Component C) The inkjet ink composition according to <1> or <2>, further containing an ethylenically unsaturated compound,
<4> The ink-jet ink composition according to <3>, wherein component C is a monofunctional ethylenically unsaturated compound,
<5> The inkjet ink composition according to <4>, wherein the content of the monofunctional ethylenically unsaturated compound is 80% by weight or more based on the total weight of Component A to Component C.
<6> The monofunctional ethylenically unsaturated compound (Component C1) is an N-vinyl compound and / or (Component C2) has 5 to 20 carbon atoms and has an aliphatic hydrocarbon ring skeleton. <6> The inkjet ink composition according to <4> or <5> above, wherein the content of <7> component C2 is 5% by weight or more based on the total weight of the ink composition. > Inkjet ink composition according to
<8> The inkjet ink composition according to <6> or <7>, wherein component C1 is N-vinylcaprolactam,
<9> The ink-jet ink according to any one of <6> to <8>, wherein the component C2 includes at least one of the compounds represented by formulas (a-1) to (a-12). Composition,

＜１０＞成分Ａの含有量が、インク組成物の全重量に対し、０．１〜５重量％である、上記＜１＞〜＜９＞のいずれか１つに記載のインクジェットインク組成物、
＜１１＞成分Ａが、式（Ａ）で表される樹脂を有する、上記＜１＞〜＜１０＞のいずれか１つに記載のインクジェットインク組成物、

<10> The inkjet ink composition according to any one of <1> to <9>, wherein the content of component A is 0.1 to 5% by weight based on the total weight of the ink composition;
<11> The ink-jet ink composition according to any one of <1> to <10>, wherein the component A has a resin represented by the formula (A),

（式（Ａ）中、Ａ¹及びＡ³はそれぞれ独立に、炭素数５〜１５のアルキレン基、芳香族炭化水素環から水素原子を２つ除いた基及び脂肪族炭化水素環から水素原子を２つ除いた基よりなる群から選ばれた二価の連結基を表し、Ａ²は側鎖にポリシロキサン構造を有する二価の連結基を表し、Ａ⁴は側鎖にエチレン性不飽和基を有する二価の連結基を表す。ｍ及びｎは、ｍ：ｎ＝１００：１〜１：１００の関係を満たす正数を表す。）
＜１２＞（成分Ｄ）重合開始剤を更に含有する、上記＜１＞〜＜１１＞のいずれか１つに記載のインクジェットインク組成物、
＜１３＞成分Ｄの含有量が、インク組成物の全重量に対し、０．０１〜１０重量％である、上記＜１２＞に記載のインクジェットインク組成物、
＜１４＞成分Ｄが、チオキサントン化合物を含む、上記＜１２＞又は＜１３＞に記載のインクジェットインク組成物、
＜１５＞（成分Ｅ）連鎖移動剤を更に含有する、上記＜１＞〜＜１４＞のいずれか１つに記載のインクジェットインク組成物、
＜１６＞成分Ｅの含有量が、インク組成物の全重量に対し、０．１〜１０重量％である、上記＜１５＞に記載のインクジェットインク組成物、
＜１７＞成分Ｅが、式（Ｓ）で表される基を有する化合物である、上記＜１５＞又は＜１６＞に記載のインクジェットインク組成物、

(In the formula (A), A ¹ and A ³ are each independently an alkylene group having 5 to 15 carbon atoms, a group obtained by removing two hydrogen atoms from an aromatic hydrocarbon ring, or a hydrogen atom from an aliphatic hydrocarbon ring. 2 represents a divalent linking group selected from the group consisting of two groups, A ² represents a divalent linking group having a polysiloxane structure in the side chain, and A ⁴ represents an ethylenically unsaturated group in the side chain. And m and n represent a positive number satisfying a relationship of m: n = 100: 1 to 1: 100.)
<12> (Component D) The inkjet ink composition according to any one of <1> to <11>, further including a polymerization initiator,
<13> The ink-jet ink composition according to <12>, wherein the content of component D is 0.01 to 10% by weight with respect to the total weight of the ink composition,
<14> Component D contains the thioxanthone compound, The inkjet ink composition as described in said <12> or <13>,
<15> (Component E) The inkjet ink composition according to any one of <1> to <14>, further including a chain transfer agent,
<16> The ink-jet ink composition according to <15>, wherein the content of component E is 0.1 to 10% by weight based on the total weight of the ink composition;
<17> The inkjet ink composition according to <15> or <16>, wherein the component E is a compound having a group represented by the formula (S),

（式（Ｓ）中、波線部分は、結合位置を表す。）
＜１８＞（ａ¹）樹脂シート上に、上記＜１＞〜＜１７＞のいずれか１つに記載のインクジェットインク組成物をインクジェット方式により吐出する工程、及び、（ｂ¹）吐出されたインクジェットインク組成物に活性光線を照射して、前記インクジェットインク組成物を硬化させる工程、を含むことを特徴とするインクジェット記録方法、
＜１９＞前記活性光線の光源が、発光ダイオードである、上記＜１８＞に記載のインクジェット記録方法、
＜２０＞樹脂シート上に上記＜１＞〜＜１７＞のいずれか１つに記載のインクジェットインク組成物の硬化画像層を設けたことを特徴とする加飾シート、
＜２１＞複数の金型により形成された空洞部の内壁に上記＜２０＞に記載の加飾シートを配置し、ゲートから前記空洞部内に溶融樹脂を注入し射出成形する工程を含むことを特徴とするインモールド成形方法。

(In formula (S), the wavy line represents the coupling position.)
<18> (a ¹⁾ on the resin sheet, the <1> a step of discharging by an inkjet method an ink-jet ink composition according to any one of ~ <17>, and, (b ¹⁾ discharged inkjet Irradiating the ink composition with an actinic ray to cure the ink-jet ink composition, and an ink jet recording method comprising:
<19> The inkjet recording method according to <18>, wherein the light source of the actinic ray is a light-emitting diode,
<20> a decorative sheet provided with a cured image layer of the inkjet ink composition according to any one of the above <1> to <17> on a resin sheet,
<21> including a step of arranging the decorative sheet according to the above <20> on the inner wall of the cavity formed by a plurality of molds, injecting molten resin from the gate into the cavity, and performing injection molding. In-mold molding method.

  According to the present invention, an ink-jet ink composition having excellent film hardness, stretchability at high temperature, and ink flow resistance of the obtained image, an ink-jet recording method using the ink-jet ink composition, and excellent stamping processability. A decorative sheet and an in-mold molding method can be provided.

It is sectional drawing which shows typically an example of the decorating sheet and decorating molded product of this invention. It is sectional drawing which shows typically an example of the in-mold shaping | molding method of this invention.

  Hereinafter, the present invention will be described in detail.

(Inkjet ink composition)
The ink-jet ink composition of the present invention (hereinafter also simply referred to as “ink composition”) has (Component A) a urethane bond in the main chain, and an ethylenically unsaturated group and a poly chain at the side chain and / or terminal. It contains a resin having a siloxane structure, and (Component B) a compound represented by the formula (B).

（式（Ｂ）中、Ｒ¹及びＲ²はそれぞれ独立に、水素原子又はメチル基を表し、Ｘ¹及びＸ²はそれぞれ独立に、単結合、エーテル結合、オキシアルキレン基又はエステル結合を表し、Ｙ¹及びＹ²はそれぞれ独立に、単結合、メチレン基、エチレンオキシ基、プロピレンオキシ基、ポリ（エチレンオキシ）基又はポリ（プロピレンオキシ）基を表し、Ｚは式（Ｚ−１）で表される基、式（Ｚ−２ａ）で表される基、式（Ｚ−２ｂ）で表される基、又は、式（Ｚ−２ａ）で表される基及び式（Ｚ−２ｂ）で表される基を２以上組み合わせた基を表す。）

(In the formula (B), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, X ¹ and X ² each independently represent a single bond, an ether bond, an oxyalkylene group or an ester bond, Y ¹ and Y ² each independently represent a single bond, a methylene group, an ethyleneoxy group, a propyleneoxy group, a poly (ethyleneoxy) group or a poly (propyleneoxy) group, and Z is represented by the formula (Z-1). Group represented by formula (Z-2a), group represented by formula (Z-2b), or group represented by formula (Z-2a) and formula (Z-2b). Represents a group in which two or more groups to be combined are combined.)

（式（Ｚ−１）、式（Ｚ−２ａ）及び式（Ｚ−２ｂ）中、波線部分は式（Ｂ）中のＹ¹及びＹ²との結合位置を表し、ｒはそれぞれ独立に１以上の整数を表す。）

(In Formula (Z-1), Formula (Z-2a) and Formula (Z-2b), the wavy line part represents the bonding position with Y ¹ and Y ^{2 in} Formula (B), and r is independently 1 (It represents the integer above.)

In addition, in this invention, description of "A-B" showing a numerical range is synonymous with "A or more and B or less." The “(component A) resin having a urethane bond in the main chain and having an ethylenically unsaturated group and a polysiloxane structure in the side chain and / or terminal” is also simply referred to as “component A” or the like.
In the present invention, “(meth) acryl” is a term including one or both of “acryl” and “methacryl”, and “(meth) acrylate” is “acrylate”. And “methacrylate”, or both.

  The ink composition of the present invention is an oil-based ink composition that can be cured by actinic radiation (also referred to as “active energy rays”). “Actinic radiation” is radiation that can give energy to generate an initial species in the ink composition by irradiation, and includes α rays, γ rays, X rays, ultraviolet rays, visible rays, electron rays, and the like. Of these, ultraviolet rays and electron beams are preferable from the viewpoint of curing sensitivity and device availability, and ultraviolet rays are more preferable.

When the ink composition of the present invention contains Component A and Component B, an inkjet ink composition having excellent film hardness, stretchability at high temperature, and ink flow resistance can be obtained.
Hereinafter, each component of the ink composition of the present invention will be described.

(Component A) Resin having a urethane bond in the main chain and having an ethylenically unsaturated group and a polysiloxane structure in the side chain and / or the terminal The ink composition of the present invention has a urethane bond in the (component A) main chain. And a resin having an ethylenically unsaturated group and a polysiloxane structure in the side chain and / or terminal.
Hereinafter, a resin having a urethane bond in the main chain and having an ethylenically unsaturated group and a polysiloxane structure in the side chain and / or the terminal, used as component A of the ink composition of the present invention will be described.
Component A is also referred to as “surface segregation polymer” as appropriate. The surface segregation polymer is presumed to be able to provide an ink jet ink composition excellent in film hardness, stretchability at high temperature, and ink flow resistance by being unevenly distributed on the surface of the cured film of the ink composition.
Hereinafter, the main chain structure, the group containing a polysiloxane structure, and the group containing an ethylenically unsaturated group constituting Component A will be described.

<Main chain structure>
Component A is a so-called polyurethane resin containing a urethane bond (—NRCOO— or —OCONR—, R represents a hydrogen atom or an optionally substituted alkyl group having 1 to 6 carbon atoms) in the main chain. Examples of the substituent include a halogen atom, a hydroxyl group, and an amino group. As the main chain structure of Component A, a polyurethane structure can be formed by reacting a polyisocyanate component such as diisocyanate and a polyol component such as diol.

  Preferred examples of the polyisocyanate component capable of forming a polyurethane structure include tolylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, norbornene diisocyanate, dicyclohexylmethane-4,4-diisocyanate, diphenylmethane- Examples include 4,4-diisocyanate and dimer acid diisocyanate.

Examples of polyol components that can form a polyurethane structure include ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,4-butanediol, 2,3-butanediol, 1,3-butanediol, neopentyl glycol, and methylpentane. Diol, 1,6-hexanediol, trimethylhexamethylenediol, 2-methyloctanediol, 1,9-nonanediol, 1,4-cyclohexanedimethanol, tricyclodecane dimethanol, polycaprolactone diol, polycarbonate diol, glycerin, Examples include trimethylolpropane, trimethyloloctane, pentaerythritol, polytetramethylene glycol and the like.
Among these, it is preferable to use a polyol having a molecular weight of 4,000 or less.

<Group containing polysiloxane structure>
The group containing a polysiloxane structure contained in component A (surface segregation polymer) in the present invention is not particularly limited as long as it has a “—Si—O—Si—” structure, but the side chain of component A And / or preferably at least one of the ends of the main chain. Specifically, it is preferable to have a group represented by the formula (a2-1) or a group represented by the formula (a2-2).

In Formula (a2-1), R ²¹ represents an alkyl group or an aryl group, W ²¹ represents a divalent linking group, and X ²¹ represents —O—, —S—, or —N (R ²⁴ )-represents any group of-. Here, R ²⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. N _a2 represents an integer of 5 to 100, and * represents a position linked to the main chain and / or the main chain end of the polymer.

The alkyl group for R ²¹ preferably has 1 to 12 carbon atoms, and may have a linear structure or a branched structure. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group. Moreover, it is more preferable that it is a C1-C6 alkyl group, it is still more preferable that it is a C1-C4 linear structure alkyl group, and a butyl group is especially preferable.

The aryl group for R ²¹ preferably has 6 to 20 carbon atoms, and more preferably 6 to 14 carbon atoms. Specific examples of the aryl group for R ²¹ include a phenyl group, a biphenyl group, and a naphthyl group, and a phenyl group is more preferable.

The divalent linking group represented by W ²¹ is preferably an alkylene group having 1 to 20 carbon atoms or an arylene group. The alkylene group may have a linear structure or a branched structure. Moreover, even if it has a substituent, it may be unsubstituted. Examples of the substituent that may have include a halogen atom.

When W ²¹ is an alkylene group having 1 to 20 carbon atoms, it is preferably unsubstituted, more preferably an unsubstituted alkylene group having 1 to 10 carbon atoms, and still more preferably 1 to 4 carbon atoms. An unsubstituted alkylene group. Specific examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, an octylene group, and a decylene group. These groups may have a linear structure or a branched structure.

When W ²¹ is an arylene group, an arylene group having 6 to 20 carbon atoms is preferable, and an arylene group having 6 to 12 carbon atoms is more preferable. Specific examples include a phenylene group, a biphenylene group, and a naphthylene group. Of these, a phenylene group is particularly preferred.

In addition, in the divalent linking group represented by W ²¹ , imino bond (—NH—), amide bond (—CONH— or —NHCO—), ester bond (—COO— or —OCO—), ether Bond (—O—), sulfonamide bond (—NHSO ₂ — or —SO ₂ NH—), urethane bond (—NHCOO— or —OCONH—), ureylene bond (—NHCONH—), carbonate bond (—OCOO—) Or a group having a heterocyclic ring (specifically, a group in which two hydrogen atoms are removed from a heterocyclic ring such as triazine, isocyanuric acid, piperazine, etc.) may intervene as a linking group.

Among these, W ²¹ is more preferably an unsubstituted alkylene group having 1 to 4 carbon atoms or an unsubstituted alkylene group having 1 to 8 carbon atoms containing an ether bond (—O—) as a bonding group. _{preferably, ** - CH 2 CH 2 -O} -CH 2 CH 2 - ** is particularly preferred (** represents a bonding position.).

X ²¹ is any one of —O—, —S—, and —N (R ²⁴ ) —. Here, R ²⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and the alkyl group may be a straight chain structure or a branched structure. Examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a tert-butyl group. Among these, R ²⁴ is preferably a hydrogen atom or a methyl group.
X ²¹ is most preferably —O— among these.

In Formula (a2-2), R ²¹ represents an alkyl group or an aryl group, W ²¹ represents a divalent linking group, and Q ²¹ represents —O—, —S—, or —N (R ²⁴ ) represents a trivalent linking group having two of any groups of-. Here, R ²⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. N _a2 represents an integer of 5 to 100, and * represents a position linked to the main chain and / or the main chain end of the polymer.

In the formula ^{(a2-2), R 21, W} 21, R 24, and n _a2 has the same meaning as ^{R 21, W 21, R 24} , and n _a2 of the formula (a2-1). Moreover, a preferable aspect is also the same.

Q ²¹ is a trivalent linking group having two groups at the end of any one of —O—, —S—, and —N (R ²⁴ ) —. The trivalent linking group represented by Q ²¹ is preferably an alkylene group having 1 to 20 carbon atoms or an arylene group. The alkylene group may have a linear structure or a branched structure. Moreover, even if it has a substituent, it may be unsubstituted. Examples of the substituent which may have include a halogen atom.

When Q ²¹ is an alkylene group having 1 to 20 carbon atoms, it is preferably unsubstituted, more preferably an unsubstituted alkylene group having 1 to 10 carbon atoms, and still more preferably 1 to 4 carbon atoms. An unsubstituted alkylene group. Specific examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, an octylene group, and a decylene group. The alkylene group may have a linear structure or a branched structure, but a branched alkylene group is more preferable.

When Q ²¹ is an arylene group, an arylene group having 6 to 20 carbon atoms is preferable, and an arylene group having 6 to 12 carbon atoms is more preferable. Specific examples include a phenylene group, a biphenylene group, and a naphthylene group.

Q ²¹ is an alkylene group or an arylene group, and has two groups of any of —O—, —S—, and —N (R ²⁴ ) —. These two groups should just exist in the arbitrary positions of an alkylene group or an arylene group.

Q ²¹ is a branched alkylene group having 3 to 10 carbon atoms, having at least two ether bonds (—O—) at different terminals, and a trivalent linking group having at least one single bond. Is more preferable.

A specific method for introducing the group represented by the formula (a2-1) or the formula (a2-2) into the main chain and / or the end of the main chain of the component A will be described later. -1) or a commercially available compound having the structure of formula (a2-2) may be applied.
As the compound containing the structure represented by the formula (a2-1) or the formula (a2-2), an alcohol compound, an amine compound, a thiol compound, or the like can be used. Specifically, a compound represented by formula (a2-3) or formula (a2-4) is more preferable.

式（ａ２−３）及び式（ａ２−４）において、Ｗ²¹、Ｒ²¹、及びｎ_a2は好ましい範囲も含めて、式（ａ２−１）及び式（ａ２−２）と同義である。
式（ａ２−４）中、Ｑ²²は、３価の連結基であり、炭素数１〜２０のアルキレン、又はアリーレン基で、直鎖でも分岐でもよいが分岐が好ましい。２個のエーテル結合と１個の単結合に繋がる３価の連結基であることが好ましい。

In formula (a2-3) and formula (a2-4), W ²¹ , R ²¹ , and na ₂ are synonymous with formula (a2-1) and formula (a2-2), including preferred ranges.
In formula (a2-4), Q ²² represents a trivalent linking group, and is an alkylene or arylene group having 1 to 20 carbon atoms, which may be linear or branched, but is preferably branched. A trivalent linking group connected to two ether bonds and one single bond is preferred.

Examples of the compounds represented by formula (a2-3) and formula (a2-4) include the following compounds (in the exemplified compounds, n _a2 is an integer of 5 to 100). However, the present invention is not limited to these.

  Moreover, the alcohol compound represented by Formula (a2-3) or Formula (a2-4) is available as a commercial item, for example, X-22-170BX, X-22 made by Shin-Etsu Chemical Co., Ltd. -170DX, X-22-173DX, SILAPLANE FM-0411, FM-0421, FM-0425, FM-DA11, FM-DA21, FM-DA26, etc. manufactured by Chisso Corporation can be exemplified.

When a group containing a polysiloxane structure is introduced into Component A, it is preferably contained at the main chain structure and / or at least one main chain terminal.
As a method for introducing a group containing a polysiloxane structure into the main chain, specifically, when a polyurethane structure is obtained by reacting the aforementioned polyisocyanate with a polyol, a diol having a group containing a polysiloxane structure is used as a polyol. What is necessary is just to use as a raw material.

  As a method for introducing a group containing a polysiloxane structure to the end of the main chain, specifically, an alcohol compound having a group having a polysiloxane structure is appropriately selected according to the structure to be introduced during the synthesis of component A. What is necessary is just to use it as a polymerization terminator. As a specific example, a monohydric alcohol compound having a group containing the above-described polysiloxane structure can be given.

Specifically, first, when a polyurethane structure is obtained by reacting the above-described polyisocyanate and polyol, the total number of isocyanate groups contained in the synthesis system is slightly excessive with respect to the total number of moles of hydroxyl groups contained. To obtain a polymer having an isocyanate group at the terminal.
Subsequently, the polysiloxane structure can be introduced into the main chain terminal of the polymer by reacting the isocyanate group formed at the polymer terminal with a monohydric alcohol compound having a group containing the polysiloxane structure. It should be noted that how much the isocyanate group is excessively small can be appropriately determined according to the molecular weight of the component A to be formed.

<Ethylenically unsaturated group>
Component A has an ethylenically unsaturated group at the side chain and / or main chain end.
It is presumed that the component A contains an ethylenically unsaturated group, so that the surface of the cured film of the ink composition can be made stronger and coated with the component A. Therefore, it is presumed that an inkjet ink composition having excellent film hardness, stretchability at high temperature, and ink flow resistance can be provided.

  Examples of ethylenically unsaturated groups include unsaturated carboxylic acid ester groups such as acrylic acid ester groups, methacrylic acid ester groups, itaconic acid ester groups, crotonic acid ester groups, isocrotonic acid ester groups, maleic acid ester groups, and styrene. And radically polymerizable groups such as groups. Of these, an acrylic ester group and a methacrylic ester group (that is, a (meth) acrylic ester group) are preferable.

  As a method for introducing an ethylenically unsaturated group into Component A, a monomer in which a reaction is blocked with a double bond of an ethylenically unsaturated group using a protective group, and after this monomer is copolymerized, the protective group is Examples thereof include a method of removing a double bond and a method of introducing a low molecular compound having an ethylenically unsaturated group into a polymer which is a starting material of component A by a polymer reaction.

  As the component A, a resin represented by the formula (A) is more preferably used.

（式（Ａ）中、Ａ¹及びＡ³はそれぞれ独立に、炭素数５〜１５のアルキレン基、芳香族炭化水素環から水素原子を２つ除いた基及び脂肪族炭化水素環から水素原子を２つ除いた基よりなる群から選ばれた二価の連結基を表し、Ａ²は側鎖にポリシロキサン構造を有する二価の連結基を表し、Ａ⁴は側鎖にエチレン性不飽和基を有する二価の連結基を表す。ｍ及びｎは、ｍ：ｎ＝１００：１〜１：１００の関係を満たす正数を表す。）

(In the formula (A), A ¹ and A ³ are each independently an alkylene group having 5 to 15 carbon atoms, a group obtained by removing two hydrogen atoms from an aromatic hydrocarbon ring, or a hydrogen atom from an aliphatic hydrocarbon ring. 2 represents a divalent linking group selected from the group consisting of two groups, A ² represents a divalent linking group having a polysiloxane structure in the side chain, and A ⁴ represents an ethylenically unsaturated group in the side chain. And m and n represent a positive number satisfying a relationship of m: n = 100: 1 to 1: 100.)

In the formula (A), A ¹ and A ³ represent a base structure to which the isocyanate group of the diisocyanate compound that can form the polyurethane structure described in the main chain structure of the component A is bonded. The preferred structure of A ¹ and A ³ can be exemplified by a matrix structure to which the isocyanate group of the diisocyanate compound exemplified in the preferred specific examples of the diisocyanate compound capable of forming the polyurethane structure described in the main chain structure of component A is bonded. .

In formula (A), A ² represents a divalent linking group having a polysiloxane structure in the side chain, and in formula (a2-2) which is a preferred example of the group having the polysiloxane structure of component A described above, Q 2 ^{When 21} has at least two ether bonds, it represents a group having a polysiloxane structure excluding two ether bonds.

In the formula (A), A ⁴ represents a divalent linking group having an ethylenically unsaturated group in the side chain, and is not particularly limited, but a group represented by the formula (a4-1) is more preferable.

式（ａ４−１）中、Ｗ²¹とＱ²¹は、式（ａ２−２）中のＷ²¹とＱ²¹と同義である。式（ａ４−１）で表される基において、Ｗ²¹としてはエステル結合が好ましく、Ｑ²¹としては分岐した炭素数３〜１０のアルキレン基で、少なくとも異なる末端に２個のエーテル結合を有し、少なくとも１個の単結合を有する３価の連結基であることが好ましい。
具体的にはエチレン性不飽和基を有する二価以上のアルコール化合物から水酸基を２つ除いた構造を表す。エチレン性不飽和基の好ましい例としては、前述の成分Ａのエチレン性不飽和基の説明で例示した基を挙げることができる。

In the formula (a4-1), W ²¹ and Q ²¹ has the same meaning as W ²¹ and Q ²¹ in the formula (a2-2). In the group represented by the formula (a4-1), W ²¹ is preferably an ester bond, Q ²¹ is a branched alkylene group having 3 to 10 carbon atoms, and has at least two ether bonds at different terminals. The trivalent linking group having at least one single bond is preferable.
Specifically, it represents a structure obtained by removing two hydroxyl groups from a divalent or higher-valent alcohol compound having an ethylenically unsaturated group. Preferable examples of the ethylenically unsaturated group include the groups exemplified in the description of the ethylenically unsaturated group of Component A described above.

A divalent or higher-valent alcohol compound having an ethylenically unsaturated group is obtained by protecting the ethylenically unsaturated group with an acetal group, for example, 2,2-dimethyl-1,3-dioxolane-4-methanol (Wako Pure Chemical Industries, Ltd. )) As a starting material, Tetrahedron Letters, 1985, 26, 3095, Angelwandte Chemie, 2007, 119, 4229, J. Am. Am. Chem. Soc. , 2002, 124, 1590, and (meth) acryloylation, styryl group introduction, vinyl etherification, and deacetalization using hydrogen chloride (methanol solution) etc. A diol having groups is obtained.
As a specific example of a divalent or higher alcohol compound having an ethylenically unsaturated group, a compound of the formula (a4-2) is preferably exemplified. As for the compound of the formula (a4-2), Bremer-GLM manufactured by NOF Corporation can be obtained as a commercial product.

  In the formula (A), when a monohydric alcohol having a polysiloxane structure is used as a raw material, a structure such as formula (Ae-a) or formula (Ae-b) added to the end of the main chain may be obtained. is there.

（式（Ａｅ−ａ）及び式（Ａｅ−ｂ）中、Ａ³、Ａ⁴、ｎは、式（Ａ）中のＡ³、Ａ⁴、ｎと同義であり、Ｗ²¹、Ｒ²¹、及びｎ_a2は、式（ａ２−３）のＷ²¹、Ｒ²¹、及びｎ_a2と同義である。）

(In the formula (Ae-a) and formula ^{(Ae-b), A 3} , A 4, n has the same meaning as A ^3, A ^4, n in the formula ^{(A), W 21, R} 21 and, n _a2 has the same meaning as W ^21, R ^21, and n _a2 of the formula (a2-3).)

Further, the main chain terminal group of the polymer represented by the formula (A) can contain various groups depending on the polymer synthesis method. By adding a known polymerization terminator, the terminal group may have a structure such as an isocyanate group, an amide group, or a hydroxyl group. Specific examples thereof include formula (Ae-1) to formula (Ae- Although the structure represented by 4) is mentioned, it is not limited to these.
Wherein (Ae-1) ~ formula ^{(Ae-4), A 1} ~A 4 has the same meaning as A ¹ to A ⁴ in the formula (A). A double wavy line part is a coupling | bonding position with the remaining part of resin of Formula (A).
The ends of the polymer of formula (A) may be the same or different at both ends.

  In formula (A), m and n represent positive numbers satisfying the relationship of m: n = 100: 1 to 1: 100. M and n represent the molar ratio of the repeating unit of Component A. Preferably, m: n = 0.1: 99.9 to 10:90, and more preferably 0.5: 99.5 to 5:95.

  The weight average molecular weight of Component A is preferably 5,000 to 200,000, more preferably 8,000 to 150,000, and still more preferably 10,000 to 100,000.

  The content of Component A contained in the ink composition of the present invention is preferably 0.1 to 10% by weight, more preferably 0.1 to 5% by weight, based on the total solid content of the ink composition. 2-3 weight% is still more preferable.

Specific preferred examples of the polymer of component A in the present invention are listed in Tables 1 and 2 below. The present invention is not limited to these specific examples.
Table 1, in Table 2, A ¹ to A ⁴ represents the A ¹ to A ⁴ of formula (A). * Represents a bonding position. When A ² is a monovalent alcohol partial structure, A ² is added to the end of the main chain.

(Component B) Compound represented by Formula (B) The ink composition of the present invention contains (Component B) a compound represented by Formula (B).

（式（Ｂ）中、Ｒ¹及びＲ²はそれぞれ独立に、水素原子又はメチル基を表し、Ｘ¹及びＸ²はそれぞれ独立に、単結合、エーテル結合、オキシアルキレン基又はエステル結合を表し、Ｙ¹及びＹ²はそれぞれ独立に、単結合、メチレン基、エチレンオキシ基、プロピレンオキシ基、ポリ（エチレンオキシ）基又はポリ（プロピレンオキシ）基を表し、Ｚは式（Ｚ−１）で表される基、式（Ｚ−２ａ）で表される基、式（Ｚ−２ｂ）で表される基、又は、式（Ｚ−２ａ）で表される基及び式（Ｚ−２ｂ）で表される基を２以上組み合わせた基を表す。）

(In the formula (B), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, X ¹ and X ² each independently represent a single bond, an ether bond, an oxyalkylene group or an ester bond, Y ¹ and Y ² each independently represent a single bond, a methylene group, an ethyleneoxy group, a propyleneoxy group, a poly (ethyleneoxy) group or a poly (propyleneoxy) group, and Z is represented by the formula (Z-1). Group represented by formula (Z-2a), group represented by formula (Z-2b), or group represented by formula (Z-2a) and formula (Z-2b). Represents a group in which two or more groups to be combined are combined.)

（式（Ｚ−１）、式（Ｚ−２ａ）及び式（Ｚ−２ｂ）中、波線部分は式（Ｂ）中のＹ¹及びＹ²との結合位置を表し、ｒはそれぞれ独立に１以上の整数を表す。）

(In Formula (Z-1), Formula (Z-2a) and Formula (Z-2b), the wavy line part represents the bonding position with Y ¹ and Y ^{2 in} Formula (B), and r is independently 1 (It represents the integer above.)

Hereinafter, the component B will be described.
Component B has a carbon-carbon double bond contained in a group represented by formula (Z-1) to formula (Z-2b) in the molecule, and has an ethylenically unsaturated group at both ends of the molecule. Therefore, it is presumed that it is unevenly distributed on the droplet surface of the ink image and contributes to the surface curability, and that both film curability and high temperature stretchability can be achieved.

In formula (B), R ¹ and R ² each independently represents a hydrogen atom or a methyl group. More preferably, R ¹ and R ² are both hydrogen atoms.

In formula (B), X ¹ and X ² each independently represent a single bond, an ether bond (—O—), an oxyalkylene group or an ester bond (—C (O) O— or —OC (O) —). And more preferably an ester bond.

In formula (B), Y ¹ and Y ² are each independently a single bond, a methylene group (—CH ₂ —), an ethyleneoxy group (—C ₂ H ₄ O— or —OC ₂ H ₄ —), propyleneoxy Represents a group (—C ₃ H ₆ O— or —OC ₃ H ₆ —), a poly (ethyleneoxy) group or a poly (propyleneoxy) group.

In the formula (B), Z is a group represented by the formula (Z-1), a group represented by the formula (Z-2a), a group represented by the formula (Z-2b), or the formula (Z- 2a) represents a group in which two or more groups represented by the group represented by formula (Z-2b) are combined. The group represented by the formula (Z-1) is a group having a structure in which two hydroxyl groups are removed from bisphenol A, and is represented by the group represented by the formula (Z-2a) and the formula (Z-2b). Is a group constituting a polybutadiene structure.
In formula (B), r is an integer greater than or equal to 1 each independently. The upper limit of r is 200, preferably 100.

Component B is particularly preferably a diacrylate compound in which R ¹ and R ² are both hydrogen atoms and X ¹ and X ² are both ester bonds.

  As the component B, when a stronger ink film is required, a compound having a group represented by the formula (Z-1) is more preferable. When a more flexible ink film is required, the compound represented by the formula (Z-2a) It is preferable to contain the compound which has the group represented by these, and the group which combined 2 or more groups represented by Formula (Z-2b).

When Z of component B has a structure represented by the formula (Z-1), Y ¹ and Y ² are each preferably a poly (ethyleneoxy) group that is independently bonded to Z by an ether bond. The number of ethyleneoxy group repeats is not particularly limited, but it is more preferable that Y ¹ and Y ² each independently have an ethyleneoxy group repeat number of 1 to 30.

  Component B is particularly preferably a compound represented by the formula (B-1a) having a bisphenol structure, having acryloxy groups at both ends, and having a poly (oxyethylene group).

(式（Ｂ−１ａ）中、ｐ及びｑは、それぞれ独立に１以上の整数を表し、ｐ＋ｑ＝３〜３０の関係を満たす。)

(In formula (B-1a), p and q each independently represent an integer of 1 or more, and satisfy the relationship of p + q = 3 to 30.)

  As component B having a bisphenol structure, NK ester A-BPE-10, A-BPE-4 (manufactured by Shin-Nakamura Chemical Co., Ltd.), SR349, SR601 (manufactured by Sartomer), Blemmer ADPE-150 (Nippon Yushi ( Co., Ltd.), Aronix M-210, M-211B (manufactured by Toagosei Co., Ltd.), light acrylate BP-4EA (manufactured by Kyoeisha Chemical Co., Ltd.), BPE-4 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), Biscoat # 700 (manufactured by Osaka Organic Chemical Co., Ltd.), Ebecryl 150, Ebecryl 1150 (manufactured by Daicel UCB Co., Ltd.) and the like can be mentioned.

Z of component B is a group represented by the formula (Z-2a), a group represented by the formula (Z-2b), or a group represented by the formula (Z-2a) and the formula (Z-2b). In the case of a structure in which two or more groups represented by the above are combined, the component B is preferably an oligomer having a polybutadiene structure.
The oligomer is generally a polymer in which a finite number of monomers (generally 5 to 100) are bonded, and a known compound called an oligomer can be arbitrarily selected. It is preferable to select a polymer having a molecular weight of 400 to 10,000 (more preferably 500 to 5,000).

Z of component B is a group represented by the formula (Z-2a), a group represented by the formula (Z-2b), or a group represented by the formula (Z-2a) and the formula (Z-2b). In the case of a structure in which two or more groups represented by the above are combined, Y ¹ and Y ² are preferably each independently a methylene group, and Component B is a polybutadiene diacrylate compound having an acryloxy group in the polybutadiene structure. Is particularly preferred.

  Examples of Component B having a polybutadiene structure and acryloxy groups at both ends include CN301, CN303, CN307 (manufactured by Sartomer) and the like as commercially available products.

Component B may be used alone or in combination of two or more as appropriate depending on the purpose.
The content of Component B in the ink composition of the present invention is preferably 0.1 to 10% by weight, more preferably 0.5 to 10% by weight, based on the total weight of the ink composition. Preferably, it is 1 to 10% by weight.

(Component C) Ethylenically Unsaturated Compound The ink composition of the present invention is a relatively low molecular weight compound having a molecular weight of 1,000 or less, different from the high molecular weight components A and B. (Component C) It is preferable to further contain a saturated compound.
Component C is a relatively low molecular weight compound having a radically polymerizable ethylenically unsaturated bond and any organic compound having at least one radically polymerizable ethylenically unsaturated bond in the molecule But you can. According to the number of ethylenically unsaturated bonds, it is classified into a monofunctional ethylenically unsaturated compound and a polyfunctional ethylenically unsaturated compound. Depending on the purpose, only one ethylenically unsaturated compound may be used, or two or more ethylenically unsaturated compounds may be used in combination at an arbitrary ratio in order to improve the desired properties.

  In the ink composition of the present invention, a monofunctional ethylenically unsaturated compound is more preferably used as Component C.

  Examples of the polymerizable compound having an ethylenically unsaturated bond capable of radical polymerization include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, and salts thereof, Examples thereof include anhydrides having a saturated group, acrylonitrile, styrene, and various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, unsaturated urethanes, and other ethylenically unsaturated compounds.

The component C monofunctional ethylenically unsaturated compound contained in the ink composition of the present invention includes (Component C1) an N-vinyl compound and / or (Component C2) an aliphatic hydrocarbon having 5 to 20 carbon atoms. It is preferable to contain a monofunctional ethylenically unsaturated compound having a ring skeleton.
Hereinafter, (Component C1) an N-vinyl compound and (Component C2) a monofunctional ethylenically unsaturated compound having 5 to 20 carbon atoms and having an aliphatic hydrocarbon ring skeleton will be described.

(Component C1) N-Vinyl Compound As the (Component C1) N-vinyl compound used in the ink composition of the present invention, N-vinyl lactams are preferably exemplified. As N-vinyl lactam, the compound represented by Formula (a) is preferable.

In the formula (a), n represents an integer of 2 to 6, and n is 3 to 5 from the viewpoint of flexibility after the ink composition is cured, adhesion to a recording medium, and availability of raw materials. It is preferable that n is 3 or 5, and n is 5, that is, N-vinylcaprolactam is particularly preferable. N-vinylcaprolactam is preferable because it is excellent in safety, is general-purpose and can be obtained at a relatively low price, and provides particularly good ink curability and good adhesion of a cured film to a recording medium.
In the N-vinyllactam, a hydrogen atom on the lactam ring may be substituted with a substituent such as an alkyl group or an aryl group, or a lactam ring and a saturated or unsaturated ring structure may be linked. Good.
The compound represented by Formula (a) may be used individually by 1 type, or may use 2 or more types together.

(Component C2) Monofunctional ethylenically unsaturated compound having 5 to 20 carbon atoms and having an aliphatic hydrocarbon ring skeleton As the monofunctional ethylenically unsaturated compound of Component C, (Component C2 ) Monofunctional ethylenically unsaturated compounds having 5 to 20 carbon atoms and having an aliphatic hydrocarbon ring skeleton can be preferably used.
By using component C2, the film hardness of the cured film of the ink image can be improved.

  As component C2, compounds represented by formulas (I) to (III) are preferably used.

（式（I）〜式（III）中、Ｒ¹は水素原子又はメチル基を表し、Ｘ¹はエーテル結合、エステル結合、アミド結合、Ｙ¹は単結合、エーテル結合、アルキレンオキシ基、ポリ（アルキレンオキシ）基の二価の連結基を表し、Ｙ¹は脂肪族炭化水素環の任意の位置に結合し、Ｒ²、Ｒ³及びＲ⁴はそれぞれ独立に置換基を表し、ｓ、ｔ及びｕはそれぞれ独立に０〜５の整数を表し、ｎは環状炭化水素構造を表す。）

(In Formula (I) to Formula (III), R ¹ represents a hydrogen atom or a methyl group, X ¹ represents an ether bond, an ester bond, an amide bond, Y ¹ represents a single bond, an ether bond, an alkyleneoxy group, a poly ( Alkylene group) represents a divalent linking group, Y ¹ is bonded to any position of the aliphatic hydrocarbon ring, R ² , R ³ and R ⁴ each independently represents a substituent, s, t and u each independently represents an integer of 0 to 5, and n represents a cyclic hydrocarbon structure.)

In the formulas (I) to (III), R ¹ represents a hydrogen atom or a methyl group, and a hydrogen atom is particularly preferable.

In formulas (I) to (III), X ¹ is an ether bond, an ester bond or an amide bond, and particularly preferably an ester bond. The ethylenically unsaturated group is particularly preferably an acryloxy group.

In formulas (I) to (III), Y ¹ represents a single bond, an ether bond, an alkyleneoxy group, or a divalent linking group of a poly (alkyleneoxy) group, and Y ¹ is an aliphatic hydrocarbon ring. Can be combined at any position. Y ¹ is more preferably a single bond or an alkyleneoxy group. A single bond is particularly preferred.

In formula (I) to formula (III), R ^{2 to} R ⁴ each independently represent a substituent, and a linear or branched alkyl group having 1 to 6 carbon atoms is more preferable. A methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, and a t-butyl group are more preferable.
s, t and u each independently represents an integer of 0 to 5, preferably an integer of 0 to 3, and in the case of 2 or more, 1 and / or 2 are present on the same carbon atom of the aliphatic hydrocarbon ring. Can be combined.
s R ² , t R ³ , and u R ⁴ may be the same or different.

  In the formula (II), when n represents a cyclic hydrocarbon structure, both ends of the cyclic hydrocarbon structure may be substituted at any position of the norbornane skeleton, and the 5-membered or 6-membered cyclic hydrocarbon structure is preferable. N may be a monocyclic structure or a polycyclic structure. Preferred examples of formula (II) include the following structures.

Wherein (II-a) ~ formula ^{(II-c), R 1} , R 3, X 1, Y 1 and t, and ^{R 1, R 3, X 1} , Y 1 and t in the formula (II) It is synonymous and a preferable aspect is also the same.

The compounds represented by the formulas (I) to (III) are preferably acrylate compounds in which an acryloxy group is directly bonded to an aliphatic hydrocarbon ring.
Specific examples of component C2 used in the ink composition of the present invention include compounds represented by formulas (a-1) to (a-12).

  The content of component C2 is preferably 5% by weight or more based on the total weight of the ink composition of the present invention. When it is 5% by weight or more, sufficient hardness can be obtained for the film of the ink image.

The content of the monofunctional ethylenically unsaturated compound of Component C is preferably 80% by weight or more based on the total weight of Component A to Component C in the ink composition.
Furthermore, in order to improve the softness | flexibility of a coating film, 80-100 weight% is preferable, as for content of a monofunctional ethylenically unsaturated compound, 85-100 weight% is more preferable, and 85-99 weight% is still more preferable.

<Other ethylenically unsaturated compounds>
The ink composition of the present invention may further contain, as component C, an ethylenically unsaturated compound other than the aforementioned component C1 and / or component C2.
As other ethylenically unsaturated compounds, known ethylenically unsaturated compounds can be used, and (meth) acrylate compounds, vinyl ether compounds, allyl compounds, N-vinyl compounds other than the above-described component C1 and / or component C2. And unsaturated carboxylic acids. For example, the radically polymerizable monomer described in JP2009-22214A, the polymerizable compound described in JP2009-209289A, and the ethylenically unsaturated compound described in JP2009-191183A can be mentioned.
Although there is no restriction | limiting in particular as another ethylenically unsaturated compound, It is more preferable to contain further monofunctional (meth) acrylate compounds other than the ethylenically unsaturated compound mentioned above.

  As the monofunctional (meth) acrylate compound other than the above-described ethylenically unsaturated compound, a compound represented by the formula (2) can be preferably used.

（式（２）中、Ｒ¹は水素原子又はメチル基を表し、Ｘは単結合又は二価の連結基を表す。）

(In formula (2), R ¹ represents a hydrogen atom or a methyl group, and X represents a single bond or a divalent linking group.)

R ¹ in Formula (2) represents a hydrogen atom or a methyl group, and a hydrogen atom is preferable from the viewpoint of curing rate.
X in Formula (2) is preferably an alkylene group or a group in which one or more alkylene groups are combined with one or more bonds selected from the group consisting of an ether bond, an ester bond, a urethane bond, and a urea bond. More preferable examples include an alkylene group, an alkyleneoxy group, and a polyalkyleneoxy group.
The alkylene group, alkyleneoxy group, or polyalkyleneoxy group preferably has 2 to 10 carbon atoms, more preferably 2 to 4 carbon atoms, and particularly preferably 2 carbon atoms. The alkylene group, alkyleneoxy group, or polyalkyleneoxy group may have a substituent, and examples of the substituent include an alkyl group, an aryl group, a halogen atom, and a hydroxy group.
Among these, as a compound represented by Formula (2), phenoxyethyl (meth) acrylate is preferable and phenoxyethyl acrylate is particularly preferable.

  Other examples of monofunctional (meth) acrylate compounds other than Component A, Component B, Component C1, and Component C2 include cyclopentyl (meth) acrylate, cycloheptyl (meth) acrylate, cyclooctyl (meth) acrylate, cyclodecyl ( (Meth) acrylate, acryloylmorpholine, N-phthalimidoethyl (meth) acrylate, pentamethylpiperidyl (meth) acrylate, tetramethylpiperidyl (meth) acrylate, 5- (meth) acryloyloxymethyl-5-ethyl-1,3- Dioxacyclohexane, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, carbitol (meth) acrylate, methyl (meth) acrylate, - butyl (meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, 2- (2-butoxyethoxy) ethyl (meth) acrylate, dimethylaminomethyl (meth) acrylate.

As another ethylenically unsaturated compound, the monofunctional (meth) acrylate compound which has an aromatic group can also be included. The cyclic structure of the aromatic group of the monofunctional (meth) acrylate compound having an aromatic group may contain heteroatoms such as O, N, and S.
Examples of monofunctional (meth) acrylate compounds having an aromatic group other than the compound represented by the formula (2) include 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, and 2-α-naphthyloxyethyl. (Meth) acrylate, 2-β-naphthyloxyethyl (meth) acrylate, 2-anthryl (meth) acrylate, 9-anthryl (meth) acrylate, 1-phenanthryl (meth) acrylate, 2-phenanthryl (meth) acrylate, ethylene Oxide-modified cresol (meth) acrylate (hereinafter “ethylene oxide” is also referred to as “EO”), p-nonylphenoxyethyl (meth) acrylate, p-nonylphenoxypolyethylene glycol (meth) acrylate, p-cumylphenoxyethylene Glycol (Meth) acrylate, 2-furyl (meth) acrylate, furfuryl (meth) acrylate, 2-thienyl (meth) acrylate, 2-thenyl (meth) acrylate, 1-pyrrolyl (meth) acrylate, 2-pyridyl (meth) acrylate 2-quinolyl (meth) acrylate, N- (1,1-dimethyl-2-phenyl) ethyl (meth) acrylamide, N-diphenylmethyl (meth) acrylamide, N-phthalimidomethyl (meth) acrylamide, N- (1 , 1'-dimethyl-3- (1,2,4-triazol-1-yl)) propyl (meth) acrylamide and the like.

In addition to the monofunctional ethylenically unsaturated compound described above, a polyfunctional (meth) acrylate compound other than Component A and Component B can be preferably used in the ink composition of the present invention.
As polyfunctional (meth) acrylate compounds other than Component A and Component B, bifunctional (meth) acrylate compounds other than Component A and Component B or trifunctional or higher (meth) acrylate compounds can be preferably used.

Examples of the bifunctional (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, Propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, polypropylene glycol diacrylate, 2,2-bis (4- (meth) ) Acryloxypolyethoxyphenyl) propane, bis (4- (meth) acryloxypolyethoxyphenyl) propane and the like.
Among these, dipropylene glycol di (meth) acrylate is preferable, and dipropylene glycol diacrylate is particularly preferable.

As the bifunctional (meth) acrylate compound, a bifunctional (meth) acrylate compound having a hydrocarbon chain which may have a branch having 5 or more carbon atoms can be preferably used.
Preferable examples of the bifunctional (meth) acrylate compound are bifunctional (meth) acrylate compounds having a hydrocarbon chain having 5 or more carbon atoms in the molecule, specifically, neopentyl glycol di (meth) acrylate, Propylene oxide (PO) modified neopentyl glycol di (meth) acrylate, hexanediol di (meth) acrylate, PO modified hexanediol di (meth) acrylate, nonanediol di (meth) acrylate, decanediol di (meth) acrylate, dodecane Diol di (meth) acrylate, tridecanediol di (meth) acrylate, octadecanediol di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, 2-n-butyl-2-ethyl- 1,3-propanedi Ruji (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, and, cyclohexanedimethanol (meth) acrylate.

  Preferable examples of the trifunctional (meth) acrylate compound include pentaerythritol tri (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate and the like. Preferable examples of the tetrafunctional (meth) acrylate compound include pentaerythritol tetra (meth) acrylate and dipentaerythritol tetra (meth) acrylate.

  Examples of other ethylenically unsaturated compounds other than Component A, Component B, Component C1, and Component C2 include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, and maleic acid. And radically polymerizable compounds such as salts thereof, anhydrides having an ethylenically unsaturated group, acrylonitrile, styrene, various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes.

  Specific examples of other ethylenically unsaturated compounds include (meth) acrylic acid derivatives such as N-methylol (meth) acrylamide, diacetone (meth) acrylamide, and epoxy (meth) acrylate, allyl glycidyl ether, diallyl phthalate, And derivatives of allyl compounds such as triallyl trimellitate.

More specifically, Shinzo Yamashita “Cross-linking agent handbook” (1981, Taiseisha); Kato Kiyosumi “UV / EB curing handbook (raw material)” (1985, Polymer publication society); Ed. “Application and Market of UV / EB Curing Technology” on page 79 (1989, CMC Publishing Co., Ltd.); “Polyester Resin Handbook” by Eiichiro Takiyama (1988, Nikkan Kogyo Shimbun) Radical polymerizable or crosslinkable monomers, oligomers and polymers known in the industry can be used.
The molecular weight of the other polymerizable compound is preferably 80 to 2,000, more preferably 80 to 1,000, and still more preferably 80 to 800.

It is also preferable to use a monofunctional vinyl ether compound as another ethylenically unsaturated compound.
Examples of the monofunctional vinyl ether compound suitably used include ethylene glycol monovinyl ether, triethylene glycol monovinyl ether, hydroxyethyl monovinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, Examples include 2-ethylhexyl vinyl ether, hydroxynonyl monovinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, dodecyl vinyl ether, diethylene glycol monovinyl ether, and the like.

Moreover, a polyfunctional vinyl ether compound can also be used.
Suitable polyfunctional vinyl ether compounds include, for example, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexane. Examples thereof include di- or trivinyl ether compounds such as dimethanol divinyl ether and trimethylolpropane trivinyl ether.

  The content of the polyfunctional (meth) acrylate compound in Component C in the ink composition of the present invention is preferably 0.01 to 15.0% by weight with respect to the total weight of the ink composition, and 0.05 to 10.0 weight% is more preferable.

(Component D) Polymerization initiator The ink composition of the present invention may preferably contain (Component D) a polymerization initiator. The ink composition ejected on the recording medium is cured by irradiation with actinic radiation. This is because the polymerization initiator contained in the ink composition of the present invention is decomposed by irradiation with actinic radiation to generate polymerization initiation species such as radicals, and the polymerization reaction of the polymerizable compound occurs in the function of the initiation species. Because it is promoted.
The polymerization initiator in the present invention is not only a compound that absorbs external energy such as actinic radiation to generate a polymerization initiating species, but also a compound that absorbs specific actinic radiation to promote decomposition of the polymerization initiator (so-called Sensitizers).
In the ink composition of the present invention, when a sensitizer is present together with a polymerization initiator, the sensitizer in the system absorbs actinic radiation to be in an excited state and contacts the polymerization initiator to decompose the polymerization initiator. It can be accelerated and a more sensitive curing reaction can be achieved. Examples of the sensitizer include those described in JP-A-2008-208190.
The polymerization initiator is a polymerization initiator used for radical polymerization reaction, and (Component D-1) a thioxanthone compound or (Component D-2) a bisacylphosphine compound is preferable. By combining the polymerization initiator and the components A to C, an ink-jet ink composition having excellent ink image film hardness, stretchability at high temperature, and ink flow resistance can be obtained.
Below, the compound of component D-1 and D-2 is demonstrated.

<(Component D-1) Thioxanthone Compound>
The ink composition of the present invention can preferably contain (Component D-1) a thioxanthone compound.
There is no restriction | limiting in particular as a thioxanthone compound, Although a well-known thing can be used, It is preferable that it is a compound represented by Formula (D-1).

In the formula (D-1), R ^1F , R ^2F , R ^3F , R ^4F , R ^5F , R ^6F , R ^7F and R ^8F are each independently a hydrogen atom, alkyl group, halogen atom, hydroxy group, cyano Group, nitro group, amino group, alkylthio group, alkylamino group (including the case of mono- and di-substitution. The same applies to the following), alkoxy group, alkoxycarbonyl group, acyloxy group, acyl group, carboxy group Represents a group or a sulfo group. The number of carbon atoms in the alkyl group, the alkylthio group, the alkylamino group, the alkoxy group, the alkoxycarbonyl group, the acyloxy group, and the alkyl moiety in the acyl group is preferably 1-20, and more preferably 1-8. Preferably, it is 1-4.
R ^1F , R ^2F , R ^3F , R ^4F , R ^5F , R ^6F , R ^7F, and R ^8F may be bonded to each other to form a ring. Examples of the ring structure in the case where these form a ring include a 5- or 6-membered aliphatic ring, an aromatic ring, etc., and may be a heterocyclic ring containing an element other than a carbon atom. The rings may be further combined to form a binuclear ring, for example, a condensed ring. These ring structures may further have a substituent. Examples of the substituent include a halogen atom, a hydroxy group, a cyano group, a nitro group, an amino group, an alkylthio group, an alkylamino group, an alkoxy group, an alkoxycarbonyl group, an acyloxy group, an acyl group, a carboxy group, and a sulfo group. N, O, and S can be mentioned as an example of a hetero atom in case the formed ring structure is a heterocyclic ring.

  Examples of the thioxanthone compound include thioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 2-dodecylthioxanthone, 2,4-dichlorothioxanthone, 2,3-diethylthioxanthone, 1-chloro-4-propoxythioxanthone, 2-cyclohexylthioxanthone, 4-cyclohexylthioxanthone, 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, 1-methoxycarbonylthioxanthone, 2-ethoxycarbonylthioxanthone, 3- (2-methoxyethoxycarbonyl) thioxanthone, 4-butoxy Carbonylthioxanthone, 3-butoxycarbonyl-7-methylthioxanthone, 1-cyano-3-chlorothioxanthone, 1-eth Sicarbonyl-3-chlorothioxanthone, 1-ethoxycarbonyl-3-ethoxythioxanthone, 1-ethoxycarbonyl-3-aminothioxanthone, 1-ethoxycarbonyl-3-phenylsulfylthioxanthone, 3,4-di [2- (2- Methoxyethoxy) ethoxycarbonyl] thioxanthone, 1-ethoxycarbonyl-3- (1-methyl-1-morpholinoethyl) thioxanthone, 2-methyl-6-dimethoxymethylthioxanthone, 2-methyl-6- (1,1-dimethoxybenzyl ) Thioxanthone, 2-morpholinomethylthioxanthone, 2-methyl-6-morpholinomethylthioxanthone, n-allylthioxanthone-3,4-dicarboximide, n-octylthioxanthone-3,4-dicarboximide, N (1,1,3,3-tetramethylbutyl) thioxanthone-3,4-dicarboximide, 1-phenoxythioxanthone, 6-ethoxycarbonyl-2-methoxythioxanthone, 6-ethoxycarbonyl-2-methylthioxanthone, thioxanthone- Examples include 2-polyethylene glycol ester, 2-hydroxy-3- (3,4-dimethyl-9-oxo-9H-thioxanthone-2-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride. Among these, thioxanthone, 2,3-diethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2-cyclohexylthioxanthone from the viewpoint of availability and curability 4-cyclohexylthioxanthone, 2-isopropylthioxanthone, and 4-isopropylthioxanthone are preferable, and 2-isopropylthioxanthone and 4-isopropylthioxanthone are more preferable.

  The content of Component D-1 is preferably from 0.1 to 5.0% by weight, more preferably from 0.5 to 3.0% by weight, based on the entire ink composition.

<(Component D-2) Bisacylphosphine compound>
(Component D-2) The bisacylphosphine compound is not particularly limited and may be a known compound, but is preferably a compound represented by the formula (D-2).

（式（Ｄ−２）中、Ｒ^1E、Ｒ^2E及びＲ^3Eはそれぞれ独立に、メチル基又はエチル基を置換基として有していてもよい芳香族炭化水素基を表す。）

(In formula (D-2), R ^1E , R ^2E and R ^3E each independently represents an aromatic hydrocarbon group optionally having a methyl group or an ethyl group as a substituent.)

A known bisacylphosphine oxide compound can be used as the bisacylphosphine compound. Examples thereof include bisacylphosphine oxide compounds described in JP-A-3-101686, JP-A-5-345790, and JP-A-6-298818.
Specific examples include bis (2,6-dichlorobenzoyl) phenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -4-ethoxy. Phenylphosphine oxide, bis (2,6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2-naphthylphosphine oxide, bis (2,6-dichlorobenzoyl) -1-naphthyl Phosphine oxide, bis (2,6-dichlorobenzoyl) -4-chlorophenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,4-dimethoxyphenylphosphine oxide, bis (2,6-dichlorobenzoyl) decylphosphite Oxide, bis (2,6-dichlorobenzoyl) -4-octylphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -2,5- Dimethylphenylphosphine oxide, bis (2,6-dichloro-3,4,5-trimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6-dichloro-3,4,5-trimethoxybenzoyl) ) -4-Ethoxyphenylphosphine oxide, bis (2-methyl-1-naphthoyl) -2,5-dimethylphenylphosphine oxide, bis (2-methyl-1-naphthoyl) -4-ethoxyphenylphosphine oxide, bis (2 -Methyl-1-naphthoyl) -2-naphth Ruphosphine oxide, bis (2-methyl-1-naphthoyl) -4-propylphenylphosphine oxide, bis (2-methyl-1-naphthoyl) -2,5-dimethylphenylphosphine oxide, bis (2-methoxy-1- Naphthoyl) -4-ethoxyphenylphosphine oxide, bis (2-chloro-1-naphthoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide Etc.

  Among these, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (IRGACURE 819: manufactured by Ciba Japan Co., Ltd.), bis (2,6-dimethoxybenzoyl) -2, 4,4-trimethylpentylphosphine oxide and the like are preferable.

  The content of component D-2 is preferably 2 to 7% by weight, more preferably 3 to 6% by weight, based on the total ink composition.

A preferred embodiment of component D in the present invention is to contain component D-1, and more preferably to contain both component D-1 and component D-2.
The total content of component D in the present invention is preferably 0.01 to 10.0% by weight of the total ink composition, more preferably 1.0 to 8.0% by weight, and 2.0 More preferably, it is ˜6.0% by weight.
By using it in combination with Component A to Component C within the above range, an ink-jet ink composition having excellent ink film hardness, stretchability at high temperature, and ink flow resistance can be obtained.

The ink composition of the present invention may contain a polymerization initiator other than the polymerization initiators of components D-1 and D-2. Other polymerization initiators include monoacylphosphine compounds, α-hydroxy ketones, α-aminoalkyl ketones, aromatic ketones, aromatic onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketos. Examples include oxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, and compounds having a carbon halogen bond.
Details of the polymerization initiator are known to those skilled in the art, and are described, for example, in paragraphs 0090 to 0116 of JP-A-2009-185186.

(Component E) Chain transfer agent The ink composition of the present invention preferably contains (Component E) a chain transfer agent.
A chain transfer agent is a functional group that receives radicals from a growing polymer chain in a chain polymerization reaction and stops the extension of the polymer, but the chain transfer agent that receives the radicals can attack the monomer and start polymerization again. Is a compound having a chain transfer group. Examples of chain transfer groups include thiol groups, disulfide groups, phenol groups, and allyl groups.

As the chain transfer group of component E preferably used in the ink composition of the present invention, a thiol group, a disulfide group, and an allyl group are preferable, a thiol group and a disulfide group are more preferable, and a thiol group is particularly preferable.
The chain transfer group in Component E may be used alone or in combination of two or more.
The number of chain transfer groups in Component E is 1 or more, more preferably 1 to 6, more preferably a plurality of chain transfer groups in one molecule, and further 2 to 6 Preferably, it is 2-4 especially preferable.

  Component E is more preferably a compound having a group represented by the formula (S).

（式（Ｓ）中、波線部分は、結合位置を表す。）

(In formula (S), the wavy line represents the coupling position.)

In formula (S), a wavy line part represents a bonding position with an organic residue serving as a mother nucleus of a compound having a group represented by formula (S).
Examples of the organic residue (mother nucleus) include an aliphatic group, an aromatic group, a heterocyclic group, or a group obtained by combining these, and any of them may have a substituent. Further, an aliphatic group, an aromatic group, or heterocyclic group may be attached by a single bond, -O -, - S -, - CO -, - NH -, - SO 2 -, and -SO- and You may couple | bond together through the bivalent coupling group chosen from the group which consists of these combinations.
Below, the chemical structure of said organic residue (parent nucleus) is explained in full detail.

The number of carbon atoms in the aliphatic group is preferably 1 to 60, more preferably 1 to 30, further preferably 1 to 20, and most preferably 1 to 10. The aliphatic group may have a double bond or a triple bond. The aliphatic group may have a cyclic structure or a branch.
The aromatic group preferably comprises a benzene ring or a naphthalene ring, and more preferably comprises a benzene ring.

The heterocyclic group preferably has a 3- to 10-membered heterocyclic ring, more preferably has a 4- to 8-membered heterocyclic ring, and most preferably has a 5- or 6-membered heterocyclic ring. The hetero atom of the heterocyclic ring is preferably a nitrogen atom, an oxygen atom or a sulfur atom. In the heterocyclic ring, an aliphatic ring, an aromatic ring or another heterocyclic ring may be condensed or spiro-bonded. Examples of heterocyclic rings include pyrrolidine ring, piperidine ring, piperazine ring, morpholine ring, tetrahydrofuran ring, tetrahydropyran ring, tetrahydrothiophene ring, dioxane ring, oxazole ring, thiazole ring, pyridine ring, pyrazine ring, triazine ring, furan ring , A thiophene ring and an isocyanuric ring. Of these, the isocyanuric ring is most preferred.
Examples of substituents for aliphatic groups, aromatic groups and heterocyclic groups include hydroxy groups, halogen atoms (eg, chlorine atoms), cyano groups, amino groups, substituted amino groups, heterocyclic groups, acyl groups and acyloxy groups. Is included. The substituent of the substituted amino group is preferably an alkyl group or an aryl group. The aromatic group and the heterocyclic group may have an alkyl group as a substituent.
However, the above substituent does not include a mercapto group or a group containing the same.

  Although the preferable specific example of the said mother nucleus is shown below, this invention is not limited to these. The position where the mercapto-containing group is bonded to the mother nucleus [the wavy line in formula (S)] is indicated by *.

  The organic residue can include a structural unit obtained by addition polymerization or polycondensation, and examples thereof include an oligovinyl group and a polyvinyl group. Component E is preferably a low molecule having a molecular weight of 10,000 or less. This will be described in detail later.

Although the specific example of the component E used for this invention is given below, it is not limited to these.
1,2-ethanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,5-pentanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol, , 9-nonanedithiol, 2,3-dimercapto-1-propanol, dithioerythritol, 2,3-dimercaptosuccinic acid, 1,2-benzenedithiol, 1,2-benzenedimethanethiol, 1,3-benzenedithiol 1,3-benzenedimethanethiol, 1,4-benzenedimethanethiol, 3,4-dimercaptotoluene, 4-chloro-1,3-benzenedithiol, 2,4,6-trimethyl-1,3- Benzenedimethanethiol, 4,4'-thiodiphenol, 2-hexylamino-4,6-dimercapto-1 , 3,5-triazine, 2-diethylamino-4,6-dimercapto-1,3,5-triazine, 2-cyclohexylamino-4,6-dimercapto-1,3,5-triazine, 2-di-n- Butylamino-4,6-dimercapto-1,3,5-triazine, ethylene glycol bis (3-mercaptopropionate), butanediol bisthioglycolate, ethylene glycol bisthioglycolate, 2,5-dimercapto-1 , 3,4-thiadiazole, 2,2 ′-(ethylenedithio) diethanethiol, compound having two mercapto groups such as 2,2-bis (2-hydroxy-3-mercaptopropoxyphenylpropane), 1, 2,6-hexanetriol trithioglycolate, 1,3,5-trithiocyanuric acid, trimethylol Compounds having three mercapto groups such as propanetris (3-mercaptopropionate) and trimethylolpropane tristhioglycolate, 4 such as pentaerythritol tetrakis (3-mercaptopropionate) and pentaerythritol tetrakisthioglycolate Examples thereof include compounds having one or more mercapto groups. These polyfunctional thiol compounds include commercially available ethylene glycol bisthiopropionate, trimethylolpropane tristhiopropionate, pentaerythritol tetrakisthiopropionate (both manufactured by Sakai Chemical Co., Ltd.), etc. is there.

In addition to the above exemplary compounds, compounds described in paragraphs 0033 to 0035 of JP-A-2009-262370 can also be used in the present invention.
These compounds include 1,2-benzenedimethanethiol, o-, m- or p-xylenedithiol, ethylene glycol bisthiopropionate, butanediol bisthiopropionate, hexanediol bisthioglycolate, 1 , 4-bis (3-mercaptobutyryloxy) butane, 2- (dimethylamino) -1,3-propanebisthiol, 1,3-dimercapto-2-propanol, 2,3-dimercapto-1-propanol, 2 , 5-diamino-1,4-benzenedithiol, etc., 1,3,5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H , 3H, 5H) -trione, trimethylolpropane tristhiopropionate, trihydroxyethyltri Trifunctional thiol compound, pentaerythritol tetrakis (3-mercaptobutyrate) having three or more polymerizable functional groups such as sosocyanuric acid tristhiopropionate and tris [(3-mercaptopropionyloxy) ethyl] isocyanurate And tetrafunctional thiol compounds such as dipentaerythritol hexakis (3-mercaptopropionate).
The component E used in the present invention is preferably a compound having a plurality of these thiol groups (also referred to as mercapto groups) (also referred to as a polyfunctional thiol compound). (3-mercaptobutyryloxy) butane (Karenz MTBD1) (trademark), pentaerythritol tetrakis (3-mercaptobutyrate) (Karenz MTPE1) (trademark), 1,3,5-tris (3-mercaptobutyryloxyethyl) ) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione (Karenz MTNR1) (trademark) (both manufactured by Showa Denko KK), trimethylolpropane tris (3- Mercaptopropionate) (TMMP), pentaerythritol tetrakis (3-mercaptopropionate) (P MP), dipentaerythritol hexakis (3-mercaptopropionate) (DPMP), tris-[(3-mercaptopropionyloxy) -ethyl] -isocyanurate (TEMPIC) (all manufactured by Sakai Chemical Industry Co., Ltd.) Etc.
Preferred specific examples are shown below in chemical structural formulas. Some compounds were also used in the examples.

  Although the molecular weight of the component E used for this invention is not specifically limited, 100-10,000 are preferable, 200-5,000 are more preferable, 200-1,000 are especially preferable. When the molecular weight is within the above range, the volatility or odor is suppressed, and the solubility or compatibility is excellent.

  The content of component E in the ink composition of the present invention is preferably 0.1 to 10% by weight, more preferably 0.5 to 5% by weight, based on the total weight of the ink composition. Moreover, these components E may use only 1 type and may use 2 or more types together.

<Colorant>
The ink composition of the present invention preferably contains a colorant in order to improve the visibility of the formed image portion. Although there is no restriction | limiting in particular as a coloring agent, The pigment and oil-soluble dye which were excellent in weather resistance and were rich in color reproducibility are preferable, and it can select and use arbitrarily from well-known coloring agents, such as a soluble dye. As the colorant, a pigment is particularly preferable. As the colorant, it is preferable to select a compound that does not function as a polymerization inhibitor from the viewpoint of not reducing the sensitivity of the curing reaction by actinic radiation.

Although it does not necessarily limit as a pigment which can be used for this invention, For example, the organic or inorganic pigment of the following number described in a color index can be used.
Examples of red or magenta pigments include C.I. I. Pigment Red 3 (also referred to as “Pigment Red 3”), 5, 19, 22, 31, 38, 42, 43, 48: 1, 48: 2, 48: 3, 48: 4, 48: 5, 49: 1, 53: 1, 57: 1, 57: 2, 58: 4, 63: 1, 81, 81: 1, 81: 2, 81: 3, 81: 4, 88, 104, 108, 112, 122, 123, 144, 146, 149, 166, 168, 169, 170, 177, 178, 179, 184, 185, 202, 208, 216, 226, 257, C.I. I. Pigment violet 3 (also referred to as “Pigment Violet 3”), 19, 23, 29, 30, 37, 50, 88, C.I. I. Pigment Orange 13 (also referred to as “Pigment Orange 13”), 16, 20, 36, blue or cyan pigments include C.I. I. Pigment Blue 1 (also referred to as “Pigment Blue 1”), 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17: 1, 22, 27, 28, 29, 36, 60, green pigments include C.I. I. Pigment Green 7 (also referred to as “Pigment Green 7”), 26, 36, 50, yellow pigments include C.I. I. Pigment Yellow 1 (also referred to as “Pigment Yellow 1”), 3, 12, 13, 14, 17, 34, 35, 37, 55, 74, 81, 83, 93, 94, 95, 97, 108, 109, 110, 120, 137, 138, 139, 150, 153, 154, 155, 157, 166, 167, 168, 180, 185, 193, black pigments include C.I. I. Pigment Black 7 (also referred to as “Pigment Black 7”), 28, 26, and white pigments include C.I. I. Pigment White 6 (also referred to as “Pigment White 6”), 18, 21 or the like can be used depending on the purpose.

  It is preferable that the colorant is appropriately dispersed in the ink composition after being added to the ink composition. For dispersing the colorant, for example, a dispersion device such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, or a paint shaker can be used.

The colorant may be directly added together with each component when preparing the ink composition. In order to improve dispersibility, it may be added to a dispersion medium such as a solvent or a polymerizable compound used in the present invention in advance and uniformly dispersed or dissolved, and then blended.
In the present invention, in order to avoid the deterioration of solvent resistance when the solvent remains in the cured image and the problem of VOC (Volatile Organic Compound) of the remaining solvent, the colorant is polymerizable. It is preferable to add and mix in advance in a dispersion medium such as a compound. That is, it is preferable not to contain a solvent. In consideration of only dispersibility, it is preferable to select a monomer having the lowest viscosity as the polymerizable compound used for the addition of the colorant. One or more colorants may be appropriately selected and used according to the purpose of use of the ink composition.

When using a colorant such as a pigment that remains solid in the ink composition, the average particle diameter of the colorant particles is preferably 0.005 to 0.5 μm, more preferably 0.01 to It is preferable to set the colorant, the dispersant, the dispersion medium, the dispersion conditions, and the filtration conditions so as to be 0.45 μm, more preferably 0.015 to 0.4 μm. This particle size control is preferable because clogging of the head nozzle can be suppressed and the storage stability, transparency, and curing sensitivity of the ink composition can be maintained.
The content of the colorant in the ink composition is appropriately selected depending on the color and purpose of use, but is preferably 0.01 to 30% by weight with respect to the weight of the whole ink composition.

<Dispersant>
The ink composition of the present invention preferably contains a dispersant. In particular, when a pigment is used, a dispersant is preferably contained in order to stably disperse the pigment in the ink composition. As the dispersant, a polymer dispersant is preferable. The “polymer dispersing agent” in the present invention means a dispersing agent having a weight average molecular weight of 1,000 or more.

Examples of the polymer dispersant include DISPERBYK-101, DISPERBYK-102, DISPERBYK-103, DISPERBYK-106, DISPERBYK-111, DISPERBYK-161, DISPERBYK-162, DISPERBYK-163, DISPERBYK-164, DISPERBYK-166, DISPERBYK-166, and DISPERBYK-166. , DISPERBYK-168, DISPERBYK-170, DISPERBYK-171, DISPERBYK-174, DISPERBYK-182 (manufactured by BYK Chemie); EFKA 7462, EFKA 7500, EFKA 7570, EFKA 7575, EFKA 7580 (manufactured by Efka Additive); Disperse Aid 6, Disperse Aid 8, Disperse Aid 15, Disperse Aid 9100 (Sannopco Co., Ltd.); 3000, 5000, 9000, 12000, 13240, 13940, 17000, 22000, 24000, 26000, 28000, 32000, 36000, 39000, 41000, 71000, and other various Solsperse dispersants (manufactured by Nippon Lubrizol Corp.); F38, L42, L44, L61, L64, F68, L72, P95, F77, P84, F87, P94, L101, P103, 108, L121, P-123 (manufactured by ADEKA Corporation); Ionette S-20 (manufactured by Sanyo Chemical Industries); Disparon KS-860, 873SN, 874 (polymer dispersing agent), # 2150 (aliphatic poly Carboxylic acid), # 7004 (polyether ester type) (manufactured by Enomoto Kasei Co., Ltd.)
The content of the dispersant in the ink composition is appropriately selected depending on the purpose of use, but is preferably 0.05 to 15% by weight with respect to the total weight of the ink composition.

<Other ingredients>
The ink composition of the present invention may contain a surfactant, a co-sensitizer, an ultraviolet absorber, an antioxidant, an antifading agent, a conductive salt, a solvent, a basic compound, etc. May be included. As these other components, known components can be used, for example, those described in JP-A-2009-22214.

The ink composition of the present invention preferably contains a polymerization inhibitor from the viewpoints of storage stability and suppression of head clogging.
The content of the polymerization inhibitor is preferably 200 to 20,000 ppm with respect to the total weight of the ink composition of the present invention.
Examples of the polymerization inhibitor include nitroso polymerization inhibitors, hindered amine polymerization inhibitors, hydroquinone, benzoquinone, p-methoxyphenol, TEMPO, TEMPOL, and cuperon Al.

(Inkjet recording method, inkjet recording apparatus, printed matter, decorative sheet, and in-mold molding method)
<Inkjet recording method>
The ink composition of the present invention is suitably used for inkjet recording.
In the inkjet recording method of the present invention, the ink composition of the present invention is ejected onto a recording medium (support, recording material, resin sheet, etc.) for inkjet recording, and the ink composition ejected onto the recording medium is used. This is a method of forming an image by irradiating actinic radiation and curing the ink. In the ink jet recording method of the present invention, the recording medium is particularly preferably a resin sheet.

More specifically, the inkjet recording method of the present invention comprises (a ¹ ) a step of ejecting the ink composition of the present invention onto a resin sheet, and (b ¹ ) actinic radiation to the ejected ink composition. Irradiating and curing the ink composition.
By including the steps (a ¹ ) and (b ¹ ), the ink jet recording method of the present invention forms an image with the ink composition cured on the resin sheet.
The printed material of the present invention is preferably a printed material recorded by the inkjet recording method of the present invention.

In addition, the ink composition of the present invention is suitably used when an image is formed on a support subjected to a molding process by an inkjet method. A molded printed matter can be produced by molding the printed matter obtained by the above-described inkjet recording method.
More specifically, the method for producing a molded printed material of the present invention includes (a ² ) a step of forming an image by ejecting the ink composition of the present invention onto a support by an ink jet method, and (b ² ) the obtained image. And irradiating actinic radiation to cure the ink composition to obtain a printed material having a cured image on the support, and (c ² ) forming the printed material. And As the forming process, embossing, vacuum forming, pressure forming, vacuum / pressure forming, drilling, and in-mold forming are preferable.

  In the present invention, the recording medium is not particularly limited, and a known recording medium can be used as a support or a recording material. For example, paper, paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), metal plate (eg, aluminum, zinc, copper, etc.), film-like or sheet-like resin (eg, cellulose diacetate, triacetic acid) Cellulose, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), paper or resin film on which the above-mentioned metal is laminated or deposited. . In addition, as the recording medium in the present invention, a non-absorbable recording medium can be preferably used. Among these, a sheet-like resin (resin sheet) is particularly preferable.

The resin as a support that can be used in the present invention is not particularly limited. However, when a printed material is subjected to a molding process or the like, a known resin described later can be used.
Specifically, polyolefin resins such as polyethylene, polypropylene, polymethylpentene, polybutene, olefin thermal plastic elastomer, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, terephthalic acid-isophthalic acid-ethylene glycol copolymer, Polyester resins such as terephthalic acid-ethylene glycol-1,4 cyclohexane dimethanol copolymer, polyester-based thermal plastic elastomer, polyamide resins such as nylon 6, nylon 9, nylon 6, 6, etc., polyvinyl fluoride, polyfluoride Fluorine resin such as vinylidene, poly (vinylidene trifluoride), ethylene-tetrafluoroethylene copolymer, polytetrafluoroethylene, acrylic resin, polyvinyl chloride, polystyrene, polycarbonate resin Etc. can be exemplified. Examples of the acrylic resin include polymethyl (meth) acrylate, polyethyl (meth) acrylate, polybutyl (meth) acrylate, methyl (meth) acrylate-butyl (meth) acrylate copolymer, ethyl (meth) acrylate-butyl (meth) ) Resin such as acrylate copolymer, methyl (meth) acrylate-styrene copolymer [However, (meth) acrylate represents acrylate or methacrylate. Can be used alone or in a mixture of two or more.
Among them, a resin sheet obtained by blending other resins with polyethylene terephthalate, polycarbonate resin, or polycarbonate resin is preferably used in terms of easy decorative printing and excellent various resistances of the finished molded product.

  In the present invention, the thickness of the thermoplastic resin sheet used for the support during the molding process (the total thickness in the case of a laminate structure) is a vacuum / pneumatic molding that combines the principles of embossing, vacuum molding, pressure molding, and vacuum / pressure molding. However, it is preferably 50 μm to 1,000 μm, more preferably 70 μm to 800 μm, and still more preferably 100 to 500 μm.

  When embossing suitability for imparting high gloss areas, low gloss areas, and thin sheet thicknesses from heat-treated plastic resin sheets, and when molding processing such as vacuum forming by heating and softening the molded printed matter Is appropriately selected in consideration of compatibility between molding suitability by heat during the molding process and durability of embossing (preventing disappearance of embossing). The layer structure of the transparent resin substrate sheet may be either a single layer or a laminate in which two or more layers of different kinds of resins are laminated.

  Additives can be appropriately added to the thermoplastic resin sheet as necessary. Appropriate amounts of various additives can be added as long as they do not interfere with the thermal behavior such as surface gloss and melting point. For example, UV stabilizers such as benzotriazole and benzophenone, light stabilizers such as hindered amine radical scavengers, lubricants such as silicone resins and waxes, colorants, plasticizers, heat stabilizers, antibacterial agents, antifungal agents , Antistatic agents and the like.

  In the present invention, the molded printed matter is produced by subjecting a thermoplastic resin sheet to vacuum forming or the like, and an image is formed on the support by an ink jet method prior to forming. The image is generally formed on the back side of the transparent sheet (the side facing the mold in vacuum forming), but an image may be formed on the opposite side. In some cases, it is also possible to form an image only on the opposite surface. In this case, the thermoplastic resin sheet serving as the substrate does not need to be transparent.

-Decorative sheet-
The decorative sheet of the present invention is preferably a form in which an image layer is provided on the resin sheet preferably used in the present invention, and the image layer is an ink-cured image of the inkjet ink composition of the present invention. Is preferred.

Below, the outline | summary of this decorating sheet is demonstrated, referring FIG.1 and FIG.2.
FIG. 1 is a schematic cross-sectional view showing an example of a decorative sheet 1 and a molded product 1A according to the present invention.
In (1) in FIG. 1, the decorative sheet 1 is provided with an image layer 4 on a resin sheet 2. This decorative sheet 1 can be used for in-mold molding.
In (2) in FIG. 1, in the molded product 1A, the decorative sheet 1 and the thermoplastic resin 8 are integrally molded.
FIG. 2 is a cross-sectional view schematically showing an example of the in-mold mold 10 used in the in-mold molding method using the decorative sheet of the present invention. The decorative sheet 1 having the image layer 4 on the resin sheet 2 is positioned and fixed in the cavity 16 formed by the fixed mold 12 and the movable mold 14. A thermoplastic resin is injected into the hollow portion 16 from the gate 18 to produce a molded product integrally with the decorative sheet.
The material used for manufacture of this decorating sheet is demonstrated below. Details of the in-mold molding will be described later.

  The resin sheet as the recording medium used in the present invention constitutes the base material of the decorative sheet. As the resin sheet, various synthetic resin films or sheets having high transparency are preferably used. Preferable examples of the synthetic resin include thermoplastic resins, and typical examples thereof include polyesters such as polycarbonate and polyethylene terephthalate, styrene, and acrylic resins.

The decorative sheet of the present invention is preferably used as an in-mold molding material.
"In-mold molding" means that a decorative sheet having an image formed on a resin sheet is inserted into a cavity formed by a plurality of, preferably a pair of molds, and then heated and melted thermoplastic resin It is injected into the hollow portion of the sheet to form a product in which the decorative sheet and the thermoplastic resin are integrally formed. In in-mold molding, the resin sheet and the image layer may be separated in the mold after injection molding. On the other hand, a molding method in which a decorative sheet fixed in a mold at the time of injection molding and an injected thermoplastic resin are integrally molded to form a final product including the resin sheet may be referred to as film insert molding.
“In-mold molding” of the present invention is a superordinate concept and includes film insert molding in addition to in-mold molding for separating a resin sheet.
The in-mold forming method will be described in detail later.

In the steps (a ¹ ) and (a ² ) in the ink jet recording method of the present invention, the ink jet recording apparatus described in detail below can be used.

<Inkjet recording apparatus>
There is no restriction | limiting in particular as an inkjet recording device used for the inkjet recording method of this invention, The well-known inkjet recording device which can achieve the target resolution can be selected arbitrarily and can be used. That is, any known inkjet recording device including a commercially available product can be applied to the resin sheet (support) in the step (a ¹ ) of the inkjet recording method of the present invention and the method (a ² ) of the method for producing a molded printed matter. Ink can be discharged.
Examples of the ink jet recording apparatus that can be used in the present invention include an apparatus including an ink supply system, a temperature sensor, and an actinic radiation source.
The ink supply system includes, for example, an original tank containing the ink composition of the present invention, a supply pipe, an ink supply tank immediately before the inkjet head, a filter, and a piezo-type inkjet head. The piezo-type inkjet head preferably has a multi-size dot of 1 to 100 pl, more preferably 8 to 30 pl, preferably 320 × 320 to 4,000 × 4,000 dpi, more preferably 400 × 400 to 1,600 ×. It can be driven so that it can discharge at a resolution of 1,600 dpi, more preferably 720 × 720 dpi. In the present invention, dpi represents the number of dots per 2.54 cm.

  As described above, since it is desirable for the radiation curable ink such as the ink composition of the present invention to have a constant temperature for the ejected ink, heat insulation and heating are performed from the ink supply tank to the inkjet head portion. It can be carried out. The temperature control method is not particularly limited, but for example, it is preferable to provide a plurality of temperature sensors at each piping site and perform heating control according to the ink flow rate and the environmental temperature. The temperature sensor can be provided near the ink supply tank and the nozzle of the inkjet head. Moreover, it is preferable that the head unit to be heated is thermally shielded or insulated so that the apparatus main body is not affected by the temperature from the outside air. In order to shorten the printer start-up time required for heating or to reduce the loss of thermal energy, it is preferable to insulate from other parts and reduce the heat capacity of the entire heating unit.

Using the above inkjet recording apparatus, the ink composition of the present invention is ejected by heating the ink composition to preferably 25 to 80 ° C., more preferably 25 to 50 ° C. Preferably it is performed after lowering to 3 to 15 mPa · s, more preferably 3 to 13 mPa · s. In particular, it is preferable to use an ink composition having an ink viscosity at 25 ° C. of 50 mPa · s or less as the ink composition of the present invention, since it can be discharged satisfactorily. By using this method, high ejection stability can be realized.
A radiation curable ink composition such as the ink composition of the present invention generally has a higher viscosity than a water-based ink usually used in ink jet recording inks, and therefore has a large viscosity fluctuation due to temperature fluctuations during ejection. The ink viscosity fluctuation has a great influence on the change of the droplet size and the change of the droplet discharge speed, and causes the image quality deterioration. Therefore, it is necessary to keep the temperature of the ink at the time of ejection as constant as possible. Therefore, in the present invention, the control range of the ink temperature is preferably set to ± 5 ° C. of the set temperature, more preferably ± 2 ° C. of the set temperature, and further preferably set temperature ± 1 ° C.

Next, (b ¹ ) a step of irradiating the ejected ink composition with actinic radiation to cure the ink composition, and (b ² ) irradiating the obtained image with actinic radiation to obtain the ink composition. The step of curing the product to obtain a printed product having a cured image on the support will be described.
The ink composition discharged on the resin sheet (support) is cured by irradiation with actinic radiation. This is because the radical polymerization initiator contained in the ink composition of the present invention is decomposed by irradiation with actinic radiation to generate an initiation species such as a radical, and the polymerization reaction of the radical polymerizable compound is a function of the initiation species. This is because it is created and promoted. At this time, if a sensitizer is present together with the polymerization initiator in the ink composition, the sensitizer in the system absorbs actinic radiation to be in an excited state, and promotes decomposition of the polymerization initiator by contacting with the polymerization initiator. And a more sensitive curing reaction can be achieved.

  Here, the actinic radiation used may be α rays, γ rays, electron beams, X rays, ultraviolet rays, visible light, infrared rays, or the like. Although the peak wavelength of actinic radiation is based also on the absorption characteristic of a sensitizer, it is preferable that it is 200-600 nm, for example, it is more preferable that it is 300-450 nm, and it is still more preferable that it is 350-420 nm.

In addition, the polymerization initiation system of the ink composition of the present invention has sufficient sensitivity even with a low output actinic radiation. Therefore, it is appropriate to cure the exposed surface with an illuminance of 10 to 4,000 mW / cm ² , more preferably 20 to 2,500 mW / cm ² .

Mercury lamps and gas / solid lasers are mainly used as actinic radiation sources, and mercury lamps and metal halide lamps are widely known as light sources used for curing UV photocurable ink jet recording inks. Yes. However, from the viewpoint of environmental protection, mercury-free is strongly desired, and replacement with a GaN-based semiconductor ultraviolet light-emitting device is very useful industrially and environmentally. Furthermore, light-emitting diodes (LEDs) and laser diodes (LDs) are small, have a long life, have high efficiency, and are low in cost, and are expected as light sources for photo-curable ink jets. In particular, when an ultraviolet light source is required, an ultraviolet LED and an ultraviolet LD can be used. For example, Nichia Corporation has introduced a purple LED whose main emission spectrum has a wavelength between 365 nm and 420 nm. If even shorter wavelengths are required, the LED may be an LED capable of emitting actinic radiation centered between 300 nm and 370 nm as disclosed in US Pat. No. 6,084,250. It can be illustrated. Other ultraviolet LEDs are also available and can emit radiation in different ultraviolet bands. The actinic radiation source particularly preferred in the present invention is a UV-LED, particularly preferably a UV-LED having a peak wavelength at 350 to 420 nm.
The maximum illumination intensity of the LED of the resin sheet is preferably 10 to 2,000 mW / cm ^2, more preferably 20 to 1,000 mW / cm ^2, is 50 to 800 mW / cm ² It is particularly preferred.

The ink composition of the present invention is appropriately irradiated with such actinic radiation for 0.01 to 120 seconds, more preferably for 0.1 to 90 seconds.
Actinic radiation irradiation conditions and a basic irradiation method are disclosed in JP-A-60-132767. Specifically, the light source is provided on both sides of the head unit including the ink ejection device, and the head unit and the light source are scanned by a so-called shuttle method. Irradiation with actinic radiation takes a certain period of time (preferably 0.01 to 0.5 seconds, more preferably 0.01 to 0.3 seconds, still more preferably 0.01 to 0.15 seconds) after ink landing. Will be done. Thus, by controlling the time from ink landing to irradiation to an extremely short time, it is possible to prevent the ink that has landed on the resin sheet from bleeding before being cured. Moreover, since it can expose before an ink osmose | permeates the deep part which a light source does not reach also with respect to a porous resin sheet, since the residue of an unreacted monomer can be suppressed, it is preferable.
Further, the curing may be completed by another light source that is not driven. International Publication No. 99/54415 pamphlet discloses a method using an optical fiber or a method of irradiating a recording unit with UV light by applying a collimated light source to a mirror surface provided on the side of the head unit as an irradiation method. Such a curing method can also be applied to the ink jet recording method and the method for producing a molded printed material of the present invention.

  By adopting the method as described above, the dot diameter of the landed ink can be kept constant even for various resin sheets (supports) having different surface wettability, and the image quality is improved. In addition, in order to obtain a color image, it is preferable to superimpose in order from the color with the highest brightness. By superimposing the inks in order of higher lightness, the irradiation line can easily reach the lower ink, and good curing sensitivity, reduction of residual monomers, and improvement in adhesion can be expected. In addition, irradiation can be performed by discharging all colors and collectively exposing, but exposure for each color is preferable from the viewpoint of promoting curing.

  In the inkjet recording method of the present invention, the order of the colored ink compositions to be ejected is not particularly limited, but it is preferably applied to the recording medium from a colored ink composition having high brightness, and yellow, cyan, When magenta and black are used, it is preferable to apply them on the recording medium in the order of yellow → cyan → magenta → black. In addition, when white is used in addition to this, it is preferable to apply on the recording medium in the order of white → yellow → cyan → magenta → black. Further, the present invention is not limited to this, and an ink set including at least a total of seven colors including yellow, light cyan, light magenta, cyan, magenta, black, and white ink compositions can be preferably used. In this case, it is preferable to apply white, light cyan, light magenta, yellow, cyan, magenta, and black on the recording medium in this order.

<Molding process>
The printed matter created using the ink composition of the present invention has suitability for forming such as embossing, vacuum forming, pressure forming, vacuum / pressure forming, or punching. A known apparatus can be used as an apparatus for forming a printed material, and may be an apparatus integrated with the ink jet recording apparatus or another apparatus.

-Embossing-
Embossing is a process of producing a three-dimensional effect by denting a printed material or the like into an arbitrary shape such as a pattern or a character, and can be processed using, for example, a roller or a press.
An example of embossing is a hot and cold press method, and the method described in JP-A-10-199360 can be referred to.
An example of an embossing apparatus by the hot and cold press method is shown below.
In the embossing apparatus, a lower surface plate (lower surface plate) and an upper surface plate (upper surface plate) are disposed so as to be able to approach and separate from each other. A plate heater is fixed on the lower surface plate, and a plate heater is also fixed on the lower surface of the upper surface plate. Thereby, hot pressing can be performed while heating the support. In this hot press machine, a mold having a convex portion that follows a predetermined emboss shape is attached to the plate-type heater on the lower surface plate, and the convex portion is brought into contact with the heater fixed to the lower surface of the upper surface plate. A mold having a concave portion that matches the shape is attached. Then, an image-formed support is disposed, a cushion sheet is disposed between the support and the concave mold, and the upper surface plate is lowered to support it between the upper surface plate and the lower surface plate. Press the body and cushion sheet. The applied pressure in this hot pressing step is, for example, 30 tons, and the heating temperature by the plate type heater is, for example, 170 ° C. And an upper surface plate is pressed on a lower surface plate, a support body and a cushion sheet are pinched between metal mold | dies, and this hot press is hold | maintained for about 3 minutes. The support is heated by a heater through a mold, and a plurality of convex portions are formed by thermal deformation. Next, the support and the cushion sheet are sandwiched between the molds and placed between the internal water-cooled surface plates without a heater. For example, the internal water-cooled surface plate with a pressure of 30 tons and a holding time of about 3 minutes. Press and cold press. Thereby, the convex shape which carried out the heat deformation by the hot press is hold | maintained, and the molded printed matter which gave the embossing process is obtained. The applied pressure and heating temperature can be appropriately adjusted according to conditions such as the material of the printed matter used and the processed shape.
When embossing a printed material prepared using the ink composition of the present invention, it is preferably performed at a temperature of 20 ° C to 150 ° C, more preferably at a temperature of 20 ° C to 100 ° C, and 25 ° C to 60 ° C. It is particularly preferable to carry out at a temperature of When the temperature is within the above-mentioned range, the color change of the image is small and processing excellent in mold release can be performed.

-Vacuum forming, pressure forming, vacuum pressure forming-
Vacuum forming is a method in which a support on which an image has been formed is preheated to a temperature at which it can be thermally deformed in advance, and this is sucked into a mold by decompression and stretched while being compressed and cooled to the mold. In this method, the support on which the image is formed is preheated to a temperature at which it can be thermally deformed in advance, pressed from the opposite side of the mold, and then pressed and cooled on the mold. Vacuum / pressure forming is a method in which the pressure reduction and pressurization are performed simultaneously.
For details, refer to Polymer Dictionary (Maruzen Co., Ltd.) p. Reference can be made to the item “thermoforming” described in 766 to 768 and the literature cited in the item. The processing temperature is appropriately determined depending on the type of support and the support, but the support is preferably molded at a temperature of 60 ° C. to 180 ° C., more preferably 80 ° C. to 160 ° C., and still more preferably 80 ° C. to 150 ° C. When the temperature is within the above-described temperature range, there is little change in the color of the image, and processing with excellent mold releasability is possible.

-Drilling-
The punching process is a process of punching a printed matter or the like into an arbitrary shape such as a figure or a character, and includes a punching process using a conventionally known press machine, a drilling process using a drill, and a laser drilling method. Among these, this is a processing method suitable for a case where many punching processes using a press machine or the like are made.
Punching using a press machine or the like is a method of shearing using a press machine in which a punching blade is installed on a printed material installed on a mold.
When punching a printed material prepared using the ink composition of the present invention, it is preferably performed at a temperature of 20 ° C to 150 ° C, more preferably at a temperature of 20 ° C to 100 ° C, and 25 ° C to 60 ° C. It is particularly preferable to carry out at a temperature of If it is in the above range, there is little change in the color of the image, and processing excellent in mold release into a mold is possible.

<In-mold molding method>
The in-mold molding method of the present invention comprises a plurality of dies, preferably a pair of dies, for example, an inner wall of a cavity formed by a fixed die and a moving die arranged opposite to each other. It includes a step of disposing a decorative sheet, injecting molten resin from the gate into the cavity, and performing injection molding.
This molding method will be described below.

The first essential step in the in-mold molding method of the present invention is a step of fixing the decorating sheet of the present invention to the inner wall of the hollow portion formed by the plurality of preferably a pair of molds. Injection molding is performed by an injection molding machine. A mold used for manufacturing a molded product is formed by, for example, a fixed mold and a movable mold that are arranged to face each other, and a hollow portion sandwiched between both molds is formed. The mold is usually made so that the molding material filled in the cavity through the sprue, runner, and gate is cooled and solidified, and then the mold is automatically opened to take out the molded product. .
Here, the hollow portion is also referred to as a cavity, and is a space portion corresponding to the shape of the molded product. This step is a step of positioning and fixing the decorative film having the printed image layer in the cavity of the mold. The image layer on the resin sheet of the decorative sheet may be fixed toward the side in contact with the mold or may be fixed toward the cavity side. In this case, the image layer of the decorative sheet is hollow. It is preferable to fix so as to be inside the portion.

The decorative sheet of the present invention can be fixed in the mold after being vacuum-formed or pressure-formed in advance. By this vacuum forming or pressure forming, it can be formed into a shape that matches a part of the external shape of the final product. In this case, in the first step, the decorative sheet preliminarily vacuum-formed or pressure-formed is placed in the mold, preferably on the fixed mold side, at a position where the molten resin injected from the gate described later is injected onto the sheet. It will be fixed.
The stretch rate of the decorative sheet in vacuum forming or pressure forming is preferably 200% or less and more preferably 150% or less in all regions of the decorative sheet. In many cases, when a thick solid is formed into a shape divided into two, the stretch ratio of the peripheral portion tends to increase.

The essential step of the second step in the in-mold molding method of the present invention is a step of injecting molten resin from the gate into the cavity and injection molding.
Here, the “gate” refers to an injection port for injecting a molten resin, which is a molding material, into a cavity in an injection mold. There are several candidates for the position of the gate that match the shape to be molded, and it is preferable to select it appropriately.

The injection molding conditions are appropriately determined depending on the type of thermoplastic resin to be injected, the shape of the molded product, and the like. Taking the case of acrylonitrile butadiene styrene (ABS) resin as an example, it is preferable that the cylinder temperature is 180 to 260 ° C., the mold temperature is 40 to 80 ° C., and the injection pressure is 500 to 1,800 kgf / cm ² . Preferable examples of the resin used for in-mold molding include thermoplastic resins, and representative examples include polyesters such as polycarbonate and polyethylene terephthalate, styrene, and acrylic resins. In addition, polyolefins such as polyethylene and polypropylene, modified polyphenylene ether, acrylonitrile-butadiene-styrene (ABS) copolymer, polyamide, or a polymer alloy composed of two or more of these may be used. Of these, ABS resin and polycarbonate are preferable.

In the molding method of the present invention, when a product is taken out from the injection mold after the injection molding step, a decorated molded product is obtained.
As already described, in the in-mold molding, the decorative sheet fixed in the mold at the time of injection molding and the injected resin are integrally molded.
In-mold molding has been applied to many fields, and has developed into a widely adopted molding method for home appliances, communication, miscellaneous goods and the like. It has greatly contributed to the popularization of mobile phones in recent years and has grown into a technology indispensable for display windows.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the present invention is not limited to these examples.
In the following description, “parts” means “parts by weight” unless otherwise specified.

The materials used in the present invention are as shown below.
・ CINQUASIA MAGENTA RT-355-D (magenta pigment, manufactured by BASF Japan Ltd.)
・ SOLSPERSE32000 (dispersant, manufactured by Nippon Lubrizol Co., Ltd.)
・ V-CAP (N-vinylcaprolactam, manufactured by ISP)
・ Polymer 1 (see the synthesis method described later)
・ Polymer 2 (see the synthesis method described later)
・ Polymer 3 (refer to the synthesis method described later)
Polymer 6 (see the synthesis method described below)
・ Polymer 9 (refer to the synthesis method described later)
Polymer 15 (see the synthesis method described below)
・ Polymer 21 (refer to the synthesis method described later)
Polymer 27 (see synthesis method below)
Polymer 33 (see the synthesis method below)
CN307 (oligomer, polybutadiene diacrylate, manufactured by Sartomer)
A-BPE-10 (diacrylate having bisphenol A structure, manufactured by Shin-Nakamura Chemical Co., Ltd.)
-PEA (SR339, phenoxyethyl acrylate, manufactured by Sartomer)
IBOA (SR506, isobornyl acrylate, manufactured by Sartomer)
・ Irg819 (IRGACURE819, bisacylphosphine photopolymerization initiator, manufactured by BASF Japan Ltd.)
・ ITX (photopolymerization initiator, isopropylthioxanthone, manufactured by Shell Chemicals Japan Co., Ltd.)
-Karenz MT-PE1 (chain transfer agent, manufactured by Showa Denko KK)

<Synthesis of Polymer 1>
In a 500 ml three-necked round bottom flask equipped with a condenser and a stirrer, FM-DA11 (Mw = 1,000, manufactured by Chisso) (1.1 g, 1 mmol), and Bremmer GLM (manufactured by NOF Corporation) 14 .85 g (93 mmol) dissolved in 2-butanone 160 ml was added. To this was added 19.4 g (103 mmol) of xylylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.) and 0.1 g of dibutyltin dilaurate (manufactured by Wako Pure Chemical Industries, Ltd.). Stir for hours. Thereafter, the mixture was heated to 70 ° C., 100 ml of 2-butanone was added, and the mixture was further heated for 2 hours.
Next, 50 ml of methyl alcohol was added to the reaction solution and stirred for 30 minutes. The reaction solution was poured into 3 l of hexane in a separately prepared container with stirring to precipitate a white polymer. The polymer was separated by filtration, washed with water, and dried under vacuum to obtain 47 g of polymer. The synthesized specific polyurethane resin had a structure represented by the specific polymer (polymer 1) in Table 1 above.
When the molecular weight was measured by gel permeation chromatography (GPC), the weight average molecular weight (polystyrene standard) was 30,000.

<Synthesis of polymers 2, 3, 6, 9, 15, 21, 27, 33>
Polymers 2, 3, 6, 9, 15, 21, 27, and 33 were synthesized in the same manner as for polymer 1 using the corresponding raw materials. As a corresponding raw material, all of the diols introducing ethylenically unsaturated groups were Blemmer GLM. As raw diisocyanates, xylylene diisocyanate was used for polymers 2, 3, and 6, dicyclohexylmethane-4,4-diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.) was used for polymer 9, and tolylene diisocyanate (Nikka Trading) was used for polymer 15. Co., Ltd.), polymer 21 with diphenylmethane-4,4-diisocyanate (Aldrich), polymer 27 with 1,6 hexamethylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.), polymer 33 with isophorone diisocyanate ( Wako Pure Chemical Industries, Ltd.) was used. As raw materials for introducing the polysiloxane structure, FM-DA11 (manufactured by Chisso) was used for polymers 2, 3, 9, 15, 21, 27, and 33, and FM-0411 (manufactured by Chisso) was used for polymer 6. When the molecular weight of each synthesized polymer was measured by gel permeation chromatography (GPC), the weight average molecular weight (polystyrene standard) was the value described in Tables 1 and 2.

<Preparation of magenta mill base>
-Magenta pigment: CINQUASIA MAGENTA RT-355D: 30 parts by weight-PEA (phenoxyethyl acrylate): 60 parts by weight-SOLPERSE 32000: 10 parts by weight The above components were stirred to obtain a magenta mill base. The pigment mill base was prepared in a disperser motor mill M50 (manufactured by Eiger) and dispersed for 8 hours at a peripheral speed of 9 m / s using zirconia beads having a diameter of 0.65 mm.

<Examples 1 to 26 and Comparative Examples 1 and 2>
-Preparation of ink composition-
Ingredients A to E, magenta mill base, and other additives were added in the amounts shown in Table 3 and mixed, followed by high-speed stirring, and ink compositions of Examples 1 to 26 and Comparative Examples 1 and 2 Respectively. In Table 3, “-” represents non-contained.

-Inkjet image recording-
Recording on a resin sheet was performed using an inkjet recording apparatus having a piezoelectric inkjet nozzle. The ink supply system was composed of an original tank, supply piping, an ink supply tank immediately before the inkjet head, a filter, and a piezo-type inkjet head, and heat insulation and heating were performed from the ink supply tank to the inkjet head portion. Temperature sensors were provided near the ink supply tank and the nozzles of the inkjet head, respectively, and temperature control was performed so that the nozzle portions were always 40 ° C. ± 2 ° C. The piezo-type inkjet head was driven so that 1 to 10 pl multi-size dots could be ejected at a resolution of 600 × 600 dpi. After landing, UV light is focused to an exposure surface illumination of 1,200 mW / cm ² and the exposure system, main scanning speed and emission frequency are adjusted so that irradiation starts 0.1 seconds after the ink composition has landed on the resin sheet. did. Further, the exposure time was variable, and exposure energy was irradiated. As the ultraviolet lamp, a UV-LED lamp (manufactured by Matsushita Electric Works Co., Ltd.) was used.
In the present invention, dpi represents the number of dots per 2.54 cm.
As the resin sheet, polycarbonate (film thickness: 500 μm, manufactured by Teijin Chemicals Ltd., trade name: Panlite) was used.

Here, since the ink image is formed by the above-described head reciprocating six times, the first hit ink is irradiated with an exposure amount corresponding to six reciprocations. Since the exposure amount is about 50 mJ / cm ² for one reciprocation, the total exposure amount for 300 reciprocations is 300 mJ / cm ² . In the following film hardness and punching suitability evaluation, evaluation was performed by controlling the number of reciprocations.

  The ink composition samples of Examples and Comparative Examples prepared above were evaluated for film hardness, heat stretching ratio, punching suitability, and ink flow resistance. Each evaluation method is as follows, and the evaluation results are shown in Table 3.

<Measurement of film hardness>
According to the inkjet recording method, a transparent substrate (polycarbonate) was used as a recording medium, and a solid image having an average film thickness of 30 μm was drawn using the ink compositions of Examples and Comparative Examples, and the ink image was 25 ° C. The pencil hardness was measured according to JIS K5600-5-4.
The standard of hardness is as follows.
5: H or higher 4: F
3: HB
2: B
1: 2B or less Evaluation 5 is the most excellent, and evaluation 3 or more is a practically acceptable range.

<Measurement of heating stretch ratio>
In accordance with the inkjet recording method, a solid image having an average film thickness of 30 μm was drawn on a transparent substrate (polycarbonate) as a resin sheet using the ink compositions of Examples and Comparative Examples, and the ink image was 5 cm × It cut | disconnected to 2 cm, it pulled on the following extending | stretching machine and temperature conditions, and measured the extending | stretching rate.
Machine used: Tensilon (manufactured by Shimadzu Corporation)
Conditions: Temperature 180 ° C., tensile speed 50 mm / min, length at break was measured and stretch ratio was calculated. Here, the stretching ratio was determined by {(length at break-length before stretching / length before stretching) × 100. ((Example) When breaking at 10 cm, {(10 cm-5 cm) / 5 cm} × 100 = 100% elongation is calculated.)
The evaluation criteria for heat stretchability are as follows.
5: Stretching rate 200% or more 4: Stretching rate 150% or more and less than 200% 3: Stretching rate 100% or more and less than 150% 2: Stretching rate 70% or more and less than 100% 1: Stretching rate 70% or less Evaluation 5 is the most excellent Therefore, a rating of 3 or higher is in a range where there is no practical problem.

<Punching aptitude>
According to the ink jet recording method, a solid image having an average film thickness of 30 μm was drawn on a transparent substrate (polycarbonate) as a resin sheet using the ink compositions of Examples and Comparative Examples to prepare an ink film. A punching test was conducted using an office punch machine under the following conditions, and the punching suitability was evaluated by visual observation and observation with an optical microscope.
Machine used: Office punching machine (Product name DP-23 Blue, manufactured by MAX)
Condition: The ink film was punched at a temperature of 25 ° C.
The evaluation criteria for punching suitability are as follows.
5: There is no cracked part by visual observation and microscopic observation.
4: Although it cannot confirm visually, when it looked with the microscope, it has confirmed that the crack location was two or less places.
3: Although it cannot confirm visually, when it looked with the microscope, it has confirmed that there were three or more places which were cracked.
2: The crack which can be visually confirmed from the punch hole periphery had generate | occur | produced.
1: The crack which spread 5 cm or more from the punch hole periphery had generate | occur | produced.
The evaluation 5 is the most excellent, and the evaluation 3 or more is a range having no practical problem.

<Ink flow resistance>
According to the ink jet recording method, a solid image having an average film thickness of 30 μm was drawn on a transparent substrate (polycarbonate) as a resin sheet using the ink compositions of Examples and Comparative Examples to prepare an ink film.
Using the following injection molding machine, the decorative sheet is fixed to the inner wall of the cavity of the 5.5 cm × 5.5 cm mold, and the ABS at 220 ° C. from the gate toward the image surface of the decorative sheet ( An acrylonitrile / butadiene / styrene resin was injected and molded. The molded product was evaluated for resistance to ink flow generated at that time.
Ink flow refers to a phenomenon in which an ink image fails to follow the expansion and contraction of high-temperature melted injection resin on which a decorative sheet ink image film has been injected during injection molding, and the length of the defective portion is measured. did.
Used injection molding machine: SG-50 manufactured by Sumitomo Heavy Industries, Ltd.
The evaluation criteria for ink flow resistance are as follows.
5: No ink flow occurred.
4: The image density of the image layer at the injected portion is thin.
3: In the image layer at the ejected portion, an ink flow of 0.1 to 0.5 cm is generated.
2: Ink flow is generated in the image layer at the ejected portion by 0.5 to 5 cm.
1: Ink flow is generated by 5 cm or more in the image layer of the ejected portion.
The evaluation 5 is the most excellent, and the evaluation 3 or more is a range having no practical problem.

1: Decorating sheet 1A: Molded product 2: Resin sheet 4: Image layer 8: Thermoplastic resin 10: Mold for in-mold molding 12: Fixed mold 14: Moving mold 16: Cavity 18: Gate

Claims (21)

(Component A) a resin having a urethane bond in the main chain and having an ethylenically unsaturated group and a polysiloxane structure in the side chain and / or terminal, and
An ink-jet ink composition comprising (Component B) a compound represented by formula (B).

(In the formula (B), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, X ¹ and X ² each independently represent a single bond, an ether bond, an oxyalkylene group or an ester bond, Y ¹ and Y ² each independently represent a single bond, a methylene group, an ethyleneoxy group, a propyleneoxy group, a poly (ethyleneoxy) group or a poly (propyleneoxy) group, and Z is represented by the formula (Z-1). Group represented by formula (Z-2a), group represented by formula (Z-2b), or group represented by formula (Z-2a) and formula (Z-2b). Represents a group in which two or more groups to be combined are combined.)

(In Formula (Z-1), Formula (Z-2a) and Formula (Z-2b), the wavy line part represents the bonding position with Y ¹ and Y ^{2 in} Formula (B), and r is independently 1 (It represents the integer above.)   The inkjet ink composition according to claim 1, wherein the content of component B is 0.5 to 10% by weight based on the total weight of the ink composition.   The inkjet ink composition according to claim 1 or 2, further comprising (Component C) an ethylenically unsaturated compound.   The inkjet ink composition according to claim 3, wherein Component C is a monofunctional ethylenically unsaturated compound.   The inkjet ink composition according to claim 4, wherein the content of the monofunctional ethylenically unsaturated compound is 80% by weight or more based on the total weight of Component A to Component C.   The monofunctional ethylenically unsaturated compound contains (component C1) an N-vinyl compound and / or (component C2) a monofunctional ethylenically unsaturated compound having 5 to 20 carbon atoms and having an aliphatic hydrocarbon ring skeleton. The inkjet ink composition according to claim 4 or 5.   The inkjet ink composition according to claim 6, wherein the component C2 is 5% by weight or more based on the total weight of the ink composition.   The inkjet ink composition according to claim 6 or 7, wherein Component C1 is N-vinylcaprolactam. The inkjet ink composition according to any one of claims 6 to 8, wherein the component C2 comprises at least one of compounds represented by formulas (a-1) to (a-12).

  The inkjet ink composition according to any one of claims 1 to 9, wherein the content of component A is 0.1 to 5% by weight based on the total weight of the ink composition. The inkjet ink composition of any one of Claims 1-10 in which the component A has resin represented by Formula (A).

(In the formula (A), A ¹ and A ³ are each independently an alkylene group having 5 to 15 carbon atoms, a group obtained by removing two hydrogen atoms from an aromatic hydrocarbon ring, or a hydrogen atom from an aliphatic hydrocarbon ring. 2 represents a divalent linking group selected from the group consisting of two groups, A ² represents a divalent linking group having a polysiloxane structure in the side chain, and A ⁴ represents an ethylenically unsaturated group in the side chain. And m and n represent a positive number satisfying a relationship of m: n = 100: 1 to 1: 100.)   The inkjet ink composition according to claim 1, further comprising (Component D) a polymerization initiator.   The inkjet ink composition according to claim 12, wherein the content of component D is 0.01 to 10% by weight based on the total weight of the ink composition.   The inkjet ink composition according to claim 12 or 13, wherein Component D comprises a thioxanthone compound.   The inkjet ink composition according to claim 1, further comprising (Component E) a chain transfer agent.   The inkjet ink composition according to claim 15, wherein the content of component E is 0.1 to 10% by weight based on the total weight of the ink composition. The inkjet ink composition according to claim 15 or 16, wherein Component E is a compound having a group represented by Formula (S).

(In formula (S), the wavy line represents the coupling position.) (A ¹⁾ on a resin sheet, a step of discharging by an inkjet method an ink-jet ink composition according to any one of claims 1 to 17 and,
(B ¹ ) A step of irradiating the ejected inkjet ink composition with actinic rays to cure the inkjet ink composition.   The ink jet recording method according to claim 18, wherein the light source of the actinic ray is a light emitting diode. A decorative sheet, wherein a cured image layer of the ink-jet ink composition according to any one of claims 1 to 17 is provided on a resin sheet. An in-mold comprising a step of disposing the decorative sheet according to claim 20 on an inner wall of a cavity formed by a plurality of molds, and injecting molten resin into the cavity from a gate and performing injection molding. Molding method.

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