JP5474621B2 - Relief printing plate precursor for laser engraving, plate making method of relief printing plate and relief printing plate - Google Patents

Description

  The present invention relates to a relief printing plate precursor for laser engraving, a method for making a relief printing plate, and a relief printing plate.

Many so-called “direct engraving CTP methods” have been proposed in which a relief forming layer is directly engraved with a laser to make a plate. Unlike the relief formation using the original film, the direct engraving CTP method can freely control the relief shape. For this reason, when an image such as a letter is formed, the area is engraved deeper than other areas, or the fine halftone dot image is engraved with a shoulder in consideration of resistance to printing pressure, etc. Is also possible.
In the case of laser engraving, debris generated during engraving adheres to the plate. Patent Document 1 discloses a method of cleaning using water, soapy water, rinsing water containing a surfactant, and the like, and a method of removing engraving residue by physical removal such as brush rubbing or high-pressure water jetting. Patent Documents 2 and 3 disclose a manufacturing method including a thermal crosslinking step and a rinsing step as a method for manufacturing a laser-engravable flexographic printing element containing an elastomer binder.

JP 2008-207419 A Special table 2004-506551 gazette JP 2009-227900 A

As a method for removing residue generated when engraving, a method of washing with water or using a combination of water washing and rubbing with a brush or the like is common. In order for the residue to be removed by washing with water, the engraving residue needs to be dispersed in water or dissolved in water. When the engraving residue is dissolved in water, the residue is less likely to remain on the plate after washing, and a good relief printing plate can be obtained. However, in order to design the waste to dissolve in water, it is necessary to increase the hydrophilicity of the relief forming layer. On the other hand, at the time of printing, since it comes into contact with water-based ink and water-based cleaning agent, water resistance is required.
An object of the present invention is to provide a relief printing plate precursor for laser engraving having excellent residue removal and water resistance, a method for making a relief printing plate using the relief printing plate precursor for laser engraving, and a relief printing plate. Is to provide.

The above problems of the present invention have been solved by means described in the following <1> to <11>.
<1> a relief printing plate precursor for laser engraving characterized by having a relief-forming layer containing (Component A) an amino group-containing polymer and (Component B) a crosslinking agent;
<2> The laser engraving according to <1>, wherein the component A is a polymer having a side chain having an amino group, and the side chain having the amino group has a structure represented by the formula (A-1). Relief printing plate precursor,

（式（Ａ−１）中、＊はポリマーの主鎖に連結する位置を表し、Ｒ¹及びＲ²は、各々独立に、水素原子、アルキル基、アリール基、アルケニル基、アルキニル基、ハロゲン原子、アルコキシ基、アシル基、又は、アルコキシカルボニル基を表し、Ｒ³は単結合又は２価の有機基を表し、Ｒ¹〜Ｒ³のいずれか２以上が結合して環を形成してもよい。）

(In formula (A-1), * represents a position linked to the main chain of the polymer, and R ¹ and R ² are each independently a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, or a halogen atom. Represents an alkoxy group, an acyl group, or an alkoxycarbonyl group, R ³ represents a single bond or a divalent organic group, and any two or more of R ^{1 to} R ³ may be bonded to form a ring. .)

<3> Component B is at least one of (Component B1) an ethylenically unsaturated compound and (Component B2) a hydrolyzable silyl group and / or a silanol group, <1> or The relief printing plate precursor for laser engraving according to <2>,
<4> The relief printing plate precursor for laser engraving according to any one of <1> to <3>, wherein the relief forming layer further comprises (Component C) a polymer not containing an amino group.
<5> For laser engraving according to any one of <1> to <4>, wherein the relief forming layer further comprises (Component C) a polymer not containing an amino group, and the Component C is a non-elastomeric material. Relief printing plate precursor,
<6> The relief printing plate precursor for laser engraving according to any one of <1> to <5>, wherein the relief-forming layer further comprises (component D) a plasticizer,
<7> The relief printing plate precursor for laser engraving according to any one of <1> to <6>, which is a flexographic printing plate precursor,
<8> The relief printing plate precursor for laser engraving according to any one of <1> to <7>, wherein the relief forming layer is a crosslinked relief forming layer that has been thermally crosslinked and / or photocrosslinked.
<9><1> to <7> The relief printing plate precursor for laser engraving according to any one of the above, a crosslinking step of crosslinking the relief forming layer with heat and / or light, and laser engraving the crosslinked relief forming layer Engraving step for forming a relief layer, and a rinsing step for rinsing engraving residue remaining on the surface of the relief layer after the engraving step using an acidic liquid,
<10> The plate making method of a relief printing plate according to <9>, wherein the acidic liquid has a pH of 1.0 to 7.0.
<11> A relief printing plate obtained by the plate making method of a relief printing plate according to <9> or <10>.

  According to the present invention, there are provided a relief printing plate precursor for laser engraving having excellent residue removal and water resistance, a method for making a relief printing plate using the relief printing plate precursor for laser engraving, and a relief printing plate. I was able to.

I. Relief printing plate precursor for laser engraving The relief printing plate precursor for laser engraving of the present invention has a relief forming layer containing (Component A) a polymer containing an amino group and (Component B) a crosslinking agent. .
In this specification, regarding the description of the relief printing plate precursor, the component A and the component B are contained, the surface as an image forming layer to be subjected to laser engraving is a flat layer, and an uncrosslinked layer is referred to as “relief formation”. Referred to as a layer. A layer obtained by crosslinking the relief forming layer is referred to as a “crosslinked relief forming layer”. Further, a layer in which irregularities are formed on the surface by laser engraving is referred to as a “relief layer”. Hereinafter, the components of the resin composition for laser engraving will be described. “X to Y” representing a numerical range is synonymous with “X or more and Y or less”.

According to the present invention, even if the rinsing process is strengthened chemically and / or mechanically, the laser engraving-type flexographic printing plate achieves excellent engraving residue removal and water resistance without impairing the uneven shape of the relief plate itself. An original version can be provided.
The relief printing plate precursor for laser engraving of the present invention having such characteristics is not particularly limited, except for the relief forming layer application of the relief printing plate precursor subjected to laser engraving, and is widely applied to other uses. be able to. The present invention can be applied to the formation of various printing plates and various molded articles that are image-formed by laser engraving, such as other material shapes that form irregularities and openings on the surface, such as intaglio plates, stencil plates, and stamps.

(Component A) Polymer Containing Amino Group The relief forming layer of the relief printing plate precursor for laser engraving of the present invention comprises (Component A) a polymer containing an amino group. Component A must contain an amino group from the viewpoint of achieving both water resistance and residue removal in an acidic solution. Component A may be any compound as long as it is a polymer having an amino group in the main chain and / or side chain portion of the polymer, and is preferably a polymer having an amino group in the side chain. The side chain having an amino group is preferably a structure represented by the formula (A-1).

（式（Ａ−１）中、＊はポリマーの主鎖に連結する位置を表し、Ｒ¹及びＲ²は、各々独立に、水素原子、アルキル基、アリール基、アルケニル基、アルキニル基、ハロゲン原子、アルコキシ基、アシル基、又は、アルコキシカルボニル基を表し、Ｒ³は単結合又は２価の有機基を表し、Ｒ¹〜Ｒ³のいずれか２以上が結合して環を形成してもよい。）

(In formula (A-1), * represents a position linked to the main chain of the polymer, and R ¹ and R ² are each independently a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, or a halogen atom. Represents an alkoxy group, an acyl group, or an alkoxycarbonyl group, R ³ represents a single bond or a divalent organic group, and any two or more of R ^{1 to} R ³ may be bonded to form a ring. .)

In formula (A-1), * indicates a position linked to the main chain of the polymer.
R ¹ and R ² each independently represents a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, a halogen atom, an alkoxy group, an acyl group, or an alkoxycarbonyl group, A branched or cyclic alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an alkoxycarbonyl group having 5 or less carbon atoms are more preferable. As the alkyl group, a methyl group, an ethyl group, an isopropyl group, and a cyclohexyl group are preferable. As the aryl group, a phenyl group and a benzyl group are preferable. As the alkoxycarbonyl group, a methoxycarbonyl group is preferable.

R ³ represents a single bond or a divalent organic group. Here, the divalent organic group is a group containing at least one carbon atom. Specifically, an alkylene group, an arylene group, a carbonyl group, an ester bond (—COO—, —OCO—), an amide bond (—NR ⁴ CO— or —CONR ⁴ — is represented, and R ⁴ represents a hydrogen atom or a carbon atom. And a linking group containing a hetero atom such as an ether bond, and a linking group obtained by combining these are preferred, and among them, a single bond or an alkylene group, a carbonyl group, an ester bond, an amide. Bonds and linking groups obtained by combining these are more preferable.
The alkylene group is preferably an alkylene group having 1 to 3 carbon atoms, more preferably a methylene group or an ethylene group.
As the linking group in which two or more linking groups are combined, a group in which an ester bond bonded to * via a carbonyl group and an alkylene group are combined, and an amide bond and an alkylene group bonded to * through a carbonyl group Are preferable, and a group in which an ester bond bonded to * via a carbonyl group and an alkylene group is more preferable.

Any two or more of R ^{1 to} R ³ may be bonded to each other to form a ring. Further, any ^one of R ^{1 to} R ³ may form a double bond with the nitrogen atom (in this case, ^one of R ^{1 and} R ² does not exist). R ¹ or R ² may be bonded to a carbon atom adjacent to the carbon atom to which * in the main chain of the polymer is linked to form a ring.

Specific examples of the ring formed by combining any two or more of R ^{1 to} R ³ include a pyrrolidine ring formed by combining R ¹ and R ^2, and R ^{1 to} R ³ bonded together. The formed 1-azabicyclo [2.2.2] octane ring is mentioned. Examples of substituting one or more carbon atoms forming a ring with a heteroatom such as O, S, and N include a morpholino ring and an imidazole ring. Moreover, R < ¹ > -R < ³ > may couple | bond together and it may form the heterocyclic aromatic amine containing a nitrogen atom, and a pyridine ring is mentioned as an example of a heterocyclic aromatic amine.

From the viewpoint of developability at pH 1.0 to 5.0, it is preferable that R ¹ and R ² are each independently a hydrogen atom, an alkyl group, or an aryl group. Preferably the total number of carbon atoms of R ¹ and R ² is 0 to 24, and more preferably the total number of carbon atoms of R ^1, R ² is 0-12.

  Introduction of the amino group into the polymer can be performed using any method. For example, a method of copolymerizing a polymerizable compound having a structure represented by the formula (A-1) alone or with another polymerizable compound, a diol having a structure represented by the formula (A-1) The method of making it polymerize with diisocyanate and dicarboxylic acid is mentioned.

  Component A preferably includes a structural unit derived from the compound represented by Formula (A-2).

（式（Ａ−２）中、Ｒ¹及びＲ²は、各々独立に、水素原子、アルキル基、アリール基、アルケニル基、アルキニル基、ハロゲン原子、アルコキシ基、アシル基、又は、アルコキシカルボニル基を表し、Ｒ³は単結合又は２価の有機基を表し、Ｒ⁴は、水素原子又はメチル基を表す。）

(In Formula (A-2), R ¹ and R ² each independently represents a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, a halogen atom, an alkoxy group, an acyl group, or an alkoxycarbonyl group. R ³ represents a single bond or a divalent organic group, and R ⁴ represents a hydrogen atom or a methyl group.)

Wherein ^{(A-2), R 1} ~R 3 is the same meaning as R ¹ to R ³ in Formula (A-1), and preferred ranges are also the same. In the present invention, among the compounds represented by the formula (A-2), a carboxylate ester bond in which a group having an amino group is bonded to a double bond in the formula (A-2) via a carbonyl group. The compound which has the group which has an amino group through the coupling group which C1-C3 alkylene group couple | bonded further to this carboxylic ester bond is more preferable.

  From the standpoint of debris removal and imparting film properties, the ratio of the structural units derived from the compound represented by the formula (A-2) in Component A is 5%, assuming that all the structural units of Component A are 100 mol%. -100 mol% is preferable, 10-70 mol% is more preferable, and 10-50 mol% is further more preferable.

  Specific examples of the compound represented by the formula (A-2) are shown below. In the exemplified compounds, R represents a hydrogen atom or a methyl group.

  As the other polymerizable compound that is polymerized together with the compound represented by the formula (A-2), an ethylenically unsaturated compound that is polymerizable with the compound represented by the formula (A-2) is preferable, and a known compound is used. Although not limited, alkyl (meth) acrylate, vinyl (meth) acrylate, allyl (meth) acrylate, etc. having a C1-C10 alkyl group having a linear, branched, or cyclic structure can be used. Alkyl polyoxyalkylene (meth) acrylate, glycidyl (meth) acrylate, styrene and the like having 1 to 5 alkenyl (meth) acrylates, alkyl groups having 1 to 3 carbon atoms and oxyalkylene groups having 2 to 4 carbon atoms are preferable.

  Specific examples of component A are listed below, but are not limited thereto. In the following specific examples, the numerical values described together with the compounds are the composition ratio (mol%) and the weight average molecular weight (Mw) of each polymer.

Next, the diol, diisocyanate, dicarboxylic acid, and diamine used in the method for polymerizing the diol having the structure represented by the formula (A-1), diisocyanate, dicarboxylic acid, and diamine will be described.
As the diol having a structure represented by the formula (A-1), a diol represented by the formula (A-3) is preferable.

（式（Ａ−３）中、Ｒ¹及びＲ²は、各々独立に、水素原子、アルキル基、アリール基、アルケニル基、アルキニル基、ハロゲン原子、アルコキシ基、アシル基、又は、アルコキシカルボニル基を表し、Ｒ³は単結合又は２価の有機基を表し、Ｒ⁴は、水素原子又はアルキル基を表し、Ｌ¹及びＬ²は、それぞれ独立に単結合又はアルキレン基を表す。）

(In Formula (A-3), R ¹ and R ² each independently represent a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, a halogen atom, an alkoxy group, an acyl group, or an alkoxycarbonyl group. R ³ represents a single bond or a divalent organic group, R ⁴ represents a hydrogen atom or an alkyl group, and L ¹ and L ² each independently represent a single bond or an alkylene group.)

Wherein ^{(A-3), R 1} ~R 3 is the same meaning as R ¹ to R ³ in Formula (A-1).
R ¹ and R ² are preferably a linear or branched alkyl group having 1 to 6 carbon atoms, a phenyl group, or a benzyl group, and more preferably a methyl group.
R ³ is preferably a single bond or an alkylene group having 1 to 3 carbon atoms, more preferably a single bond or a methylene group, and still more preferably a methylene group.
R ⁴ represents a hydrogen atom or an alkyl group, preferably a hydrogen atom, a methyl group or an ethyl group, and more preferably a hydrogen atom.
L ¹ and L ² each independently represent a single bond or an alkylene group, preferably a single bond or a methylene group, and more preferably ^one of L ¹ and L ² is a single bond and the other is a methylene group.
Examples of the diol represented by the formula (A-3) include the following.

  Further, as in the following specific examples, a diol containing a nitrogen atom in addition to a carbon atom between two hydroxy groups in place of or in combination with the diol having the structure represented by the formula (A-1) Can also be suitably used.

Examples of the diol that can be used in combination with the diol having the structure represented by the formula (A-1) include alkylene glycol, polyalkylene glycol, polyester diol, and polycarbonate diol.
Specific examples of such diol compounds include those shown below. That is, polyalkylene glycol such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, neopentyl glycol, 1,3-butylene glycol, 1 , 4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-butene-1,4-diol, 2-butyne-1,4-diol, 2,2,4-trimethyl-1, 3-pentanediol, 2,2-diethyl-1,3-propanediol, 1,4-bis-β-hydroxyethoxycyclohexane, cyclohexanediol, cyclohexanedimethanol, tricyclodecane dimethanol Hydrogenated bisphenol A, diethyl 2,2-dimethylolmalonate, bis- (2-hydroxyethyl) sulfide, hydrogenated bisphenol F, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, bis-phenol F Ethylene oxide adduct, bisphenol F propylene oxide adduct, hydrogenated bisphenol A ethylene oxide adduct, hydrogenated bisphenol A propylene oxide adduct, hydroquinone dihydroxyethyl ether, p-xylylene glycol, dihydroxyethyl sulfone, bis (2-hydroxyethyl) -2,4-tolylenedicarbamate, 2,4-tolylene-bis (2-hydroxyethylcarbamide), bis (2-hydroxyethyl) -m-xylylenedicarba Examples include ester compounds of (meth) acrylic acid such as rubamate, bis (2-hydroxyethyl) isophthalate, 2,3-dihydroxypropane (meth) acrylate and triol compounds having 3 to 10 carbon atoms, polyester diols, polycarbonate diols, and the like. Can be mentioned.

  Specific examples of the diisocyanate include 2,4-tolylene diisocyanate, dimer of 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-xylylene diisocyanate, metaxylylene diisocyanate, 4,4 ′. -Aromatic diisocyanate compounds such as diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3′-dimethylbiphenyl-4,4′-diisocyanate; hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, dimer acid diisocyanate, etc. Aliphatic diisocyanate compounds such as: isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), methylcyclohexane-2,4 (or 2, A reaction product of a diol and a diisocyanate such as an adduct of 1 mol of 1,3-butylene glycol and 2 mol of tolylene diisocyanate; an alicyclic diisocyanate compound such as diisocyanate and 1,3- (isocyanatomethyl) cyclohexane; A certain diisocyanate compound etc. are mentioned. Among these, from the viewpoint of adjusting the elastic modulus of the film, those having an aromatic ring such as 4,4'-diphenylmethane diisocyanate, and aliphatic diisocyanate compounds such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate are preferable.

Dicarboxylic acids include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, tetrabromophthalic acid, tetrachlorophthalic acid; adipic acid, azelaic acid, succinic acid, succinic acid, suberic acid, sebacic acid, malonic acid, Examples include saturated aliphatic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid. Among them, two carboxy groups are bonded by a single bond, an alkylene group having 1 to 10 carbon atoms, and an arylene group having 6 to 12 carbon atoms. Group dicarboxylic acids are preferred.
Examples of diamines include ethylene diamine, propylene diamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, heptamethylene diamine, octamethylene diamine, dodecamethylene diamine, propane-1,2-diamine, and bis (3-aminopropyl) methylamine. 1,3-bis (3-aminopropyl) tetramethylsiloxane, piperazine, 2,5-dimethylpiperazine, N- (2-aminoethyl) piperazine, 4-amino-2,2,6,6-tetramethylpiperidine , N, N-dimethylethylenediamine, lysine, L-cystine, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-tolylenediamine, benzidine, o-ditoluidine, o-dianisidine, 4-nitro m-phenylenediamine, 2,5-dimethoxy-p-phenylenediamine, bis- (4-aminophenyl) sulfone, 4-carboxy-o-phenylenediamine, 3-carboxy-m-phenylenediamine, 4,4′-diamino Examples include diphenyl ether and 1,8-naphthalenediamine.

  Component A includes (1) a resin composed of a structural unit derived from a combination of a diol having a structure represented by the formula (A-1), a polyalkylene glycol, and an aromatic diisocyanate, and (2) a formula (A- 1) a resin composed of a structural unit derived from a combination of a diol, a polyalkylene glycol, an aromatic diisocyanate, and an aliphatic diisocyanate having a structure represented by (1), and (3) a structure represented by the formula (A-1) A diol, a resin comprising a structural unit derived from a combination of an ester compound of (meth) acrylic acid and a triol compound having 3 to 10 carbon atoms, a polyalkylene glycol, an aromatic diisocyanate, and an aliphatic diisocyanate, and (4 Diol having a structure represented by formula (A-1), polyalkylene glycol, fat Family dicarboxylic acid, and a resin consisting of structural units derived from a combination of aliphatic diamines are preferred.

In the present invention, the total amount of structural units contained in component A is 100 mol%, and the content of structural units derived from the diol having the structure represented by formula (A-1) is 10 to 40 mol%. It is preferably 15 to 35 mol%, more preferably 20 to 30 mol%.
Component A preferably contains a structural unit derived from polyalkylene glycol, and the content when the total amount of structural units contained in Component A is 100 mol% is preferably 1 to 35 mol%. -30 mol% is more preferable, and 10-25 mol% is still more preferable.
When component A contains a structural unit derived from a diisocyanate compound, it preferably contains a structural unit derived from an aromatic diisocyanate compound. The content of the structural unit derived from the aromatic diisocyanate compound is preferably 15 to 50 mol%, more preferably 30 to 50 mol%, with the total amount of the structural units contained in Component A being 100 mol%.
Moreover, the aspect which uses together an aromatic diisocyanate compound and an aliphatic diisocyanate compound is also preferable.

  Specific examples PB-1 to PB-28 of component A are shown below. In the specific examples PB-1 to PB-28, the numerical value described together with the compound is the reaction ratio (mol%) of each component. “PEG” represents polyethylene glycol, “PPG” represents polypropylene glycol, and the subsequent numbers represent the weight average molecular weight.

  The weight average molecular weight of Component A is preferably 5,000 to 100,000, preferably 10,000 to 90,000, and more preferably 50,000 to 80,000. When the weight average molecular weight is 5,000 or more, the residue removal and water resistance are excellent, and when it is 100,000 or less, the elasticity of the film is appropriate and the viscosity of the treatment liquid is also appropriate.

  Component A may be used alone or in combination of two or more. The content of Component A is preferably 5 to 75% by mass, more preferably 10 to 70% by mass, based on the total solid content of the relief forming layer as 100% by mass, from the viewpoint of good image area strength and image formability. 10-60 mass% is still more preferable.

(Component B) Crosslinking agent The relief forming layer of the relief printing plate precursor for laser engraving of the present invention comprises (Component B) a crosslinking agent. Examples of (Component B) crosslinking agent include (Component B1) an ethylenically unsaturated compound, and (Component B2) a compound having a hydrolyzable silyl group and / or a silanol group. In the present invention, the relief forming layer preferably contains at least one compound as a crosslinking agent. Hereinafter, the component B1 and the component B2 will be described.

(Component B1) Ethylenically unsaturated compound (Component B1) An ethylenically unsaturated compound is a compound having at least one ethylenically unsaturated bond that can be radically polymerized by an initiation radical generated from a polymerization initiator. . By containing an ethylenically unsaturated compound, the relief-forming layer can be given properties that can be cured by crosslinking.

  The ethylenically unsaturated compound can be arbitrarily selected from compounds having at least 1, preferably 2 or more, more preferably 2 to 6 ethylenically unsaturated bonds. The ethylenically unsaturated compound preferably has a weight average molecular weight of less than 5,000. Component B1 does not include a polymer containing an amino group and a compound having a hydrolyzable silyl group and / or a silanol group. The ethylenically unsaturated compound is not particularly limited and may be a known compound, and examples thereof include the polymerizable compounds described in paragraphs 0098 to 0124 of JP2009-255510A and JP2009-204962A. it can.

In the relief forming layer in the present invention, a crosslinked structure is preferably formed, and a polyfunctional monomer is preferably used as Component B1. The molecular weight of these polyfunctional monomers is preferably 120 to 3,000, more preferably 200 to 2,000.
Monofunctional monomers and polyfunctional monomers include esters of unsaturated carboxylic acids (acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.) and polyhydric alcohol compounds, unsaturated carboxylic acids and polyvalent monomers. Examples include amides with amine compounds.
Specific examples of the monomer of an ester of an aliphatic polyhydric alcohol compound and an unsaturated carboxylic acid include (meth) acrylic acid ester, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, 1, 3 -Butanediol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane tri (( (Meth) acryloyloxypropyl) ether, trimethylolethane tri (meth) acrylate, hexanediol di (meth) acrylate, 1,4-cyclohexanediol di (meth) acrylate, tetraethylene Recall di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, sorbitol tri (Meth) acrylate, sorbitol tetra (meth) acrylate, sorbitol penta (meth) acrylate, sorbitol hexa (meth) acrylate, tri ((meth) acryloyloxyethyl) isocyanurate, polyester (meth) acrylate oligomer, bis [p- ( 3- (Meth) acryloxy-2-hydroxypropoxy) phenyl] dimethylmethane, bis- [p-((meth) acryloxyethoxy) Dimethyl] dimethylmethane, di (meth) acrylate of hydrogenated bisphenol A, di (meth) acrylate of hydrogenated bisphenol F, di (meth) acrylate of ethylene oxide adduct of bisphenol A, dipropylene oxide adduct of bisphenol A (Meth) acrylate, di (meth) acrylate of ethylene oxide adduct of bisphenol F, di (meth) acrylate of propylene oxide adduct of bisphenol F, di (meth) acrylate of ethylene oxide adduct of hydrogenated bisphenol A, water And di (meth) acrylates of propylene oxide adducts of bisphenol A, among others, pentaerythritol or dipentaerythritol derivatives of 2-6 functional (meth) acrylates, and bisphenol Di- (meth) acrylate is preferable, and dipentaerythritol hexa (meth) acrylate or bisphenol A-type di (meth) acrylate is more preferable. As the bisphenol A type di (meth) acrylate, those having 1 to 6 ethylene oxide groups added per molecule are more preferable. The ester monomers can also be used as a mixture.

  The content of the (component B1) ethylenically unsaturated compound in the relief forming layer is 5 to 60 from the viewpoint of flexibility and brittleness of the crosslinked film, in terms of solid content, with the total mass of the relief forming layer being 100% by mass. % By mass is preferable, and 8 to 30% by mass is more preferable.

(Component B2) Compound having a hydrolyzable silyl group and / or silanol group The “hydrolyzable silyl group” in Component B2 is a silyl group having hydrolyzability. Examples of the hydrolyzable group include an alkoxy group, a mercapto group, a halogen atom, an amide group, an acetoxy group, an amino group, and an isopropenoxy group. The silyl group is hydrolyzed to become a silanol group, and the silanol group is dehydrated and condensed to form a siloxane bond. Such a hydrolyzable silyl group or silanol group is preferably represented by the formula (B2-1).

In the formula (B2-1), at least one of R ^{1 to} R ³ is a hydrolysis selected from the group consisting of an alkoxy group, a mercapto group, a halogen atom, an amide group, an acetoxy group, an amino group, and an isopropenoxy group. Represents a sex group or a hydroxy group. The remaining R ^{1 to} R ³ are each independently a hydrogen atom, a halogen atom, or a monovalent organic substituent (for example, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, and an aralkyl group can be exemplified). Represent.
In formula (B2-1), the hydrolyzable group bonded to the silicon atom is particularly preferably an alkoxy group or a halogen atom, and more preferably an alkoxy group. As an alkoxy group, from a viewpoint of rinse property and printing durability, a C1-C30 alkoxy group is preferable, More preferably, it is C1-C15 alkoxy group, More preferably, it is C1-C5, Most preferably An alkoxy group having 1 to 3 carbon atoms, most preferably a methoxy group or an ethoxy group. Examples of the halogen atom include an F atom, a Cl atom, a Br atom, and an I atom. From the viewpoint of ease of synthesis and stability, a Cl atom and a Br atom are preferable, and a Cl atom is more preferable.

Component B2 is preferably a compound having one or more groups represented by formula (B2-1), and more preferably a compound having two or more groups. Particularly preferred are compounds having two or more hydrolyzable silyl groups. That is, a compound having two or more silicon atoms having a hydrolyzable group bonded in the molecule is preferably used. 2-6 are preferable and, as for the number of the silicon atoms which the hydrolyzable group contained in component B2 couple | bonded, 2 or 3 is more preferable.
The hydrolyzable group can be bonded to one silicon atom in the range of 1 to 4, and the total number of hydrolyzable groups in the formula (B2-1) is in the range of 2 or 3. preferable. In particular, it is preferable that three hydrolyzable groups are bonded to a silicon atom. When two or more hydrolyzable groups are bonded to a silicon atom, they may be the same as or different from each other.

Preferred examples of the alkoxy group as the hydrolyzable group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a tert-butoxy group, a phenoxy group, and a benzyloxy group. A plurality of these alkoxy groups may be used in combination, or a plurality of different alkoxy groups may be used in combination.
Examples of the alkoxysilyl group to which the alkoxy group is bonded include, for example, a trialkoxysilyl group such as a trimethoxysilyl group, a triethoxysilyl group, a triisopropoxysilyl group, a triphenoxysilyl group; a dimethoxymethylsilyl group, a diethoxymethylsilyl group And dialkoxymonoalkylsilyl groups such as methoxydimethylsilyl group and ethoxydimethylsilyl group.

Component B2 preferably has at least a sulfur atom, an ester bond, a urethane bond, an ether bond, a urea bond, or an imino group. Especially, it is preferable that component B2 contains a sulfur atom from a crosslinkable viewpoint. Moreover, it is preferable that component B2 is a compound which does not have an ethylenically unsaturated bond.
Component B2 includes a compound in which a plurality of groups represented by the formula (B2-1) are bonded via a divalent linking group. Such a divalent linking group includes a viewpoint of effects. To a linking group having a sulfide group (-S-).
There is no restriction | limiting in particular as a synthesis method of component B2, It can synthesize | combine by a well-known method. A typical synthesis method of component B2 containing a linking group having the above specific structure is shown below.

<Synthesis Method of Component B2 Having Sulfide Group as Linking Group>
The method for synthesizing component B2 having a sulfide group as a linking group is not particularly limited, but reaction of component B2 having a halogenated hydrocarbon group and alkali sulfide, reaction of component B2 having a mercapto group and halogenated hydrocarbon, mercapto group Reaction of component B2 having a halogenated hydrocarbon group and component B2 having a halogenated hydrocarbon group, reaction of a component B2 having a halogenated hydrocarbon group and a mercaptan, reaction of component B2 having an ethylenically unsaturated bond and a mercaptan, ethylenic unsaturation Reaction of component B2 having a bond and component B2 having a mercapto group, reaction of a compound having an ethylenically unsaturated bond and component B2 having a mercapto group, reaction of a ketone and a component B2 having a mercapto group, a diazonium salt and a mercapto group Reaction of component B2 having a component, component B2 having a mercapto group and oxiranes Examples of reaction, synthesis of component B2 having a mercapto group and component B2 having an oxirane group, reaction of a mercaptan and component B2 having an oxirane group, reaction of a component B2 having a mercapto group and aziridines, etc. it can.

  Component B2 is preferably a compound represented by the following formula (B2-2) or formula (B2-3).

（式（Ｂ２−２）及び式（Ｂ２−３）中、Ｒ^Bはエステル結合、アミド結合、ウレタン結合、ウレア結合、又は、イミノ基を表し、Ｌ¹はｎ価の連結基を表し、Ｌ²は二価の連結基を表し、Ｌ^s1はｍ価の連結基を表し、Ｌ³は二価の連結基を表し、ｎ及びｍはそれぞれ独立に１以上の整数を表し、Ｒ¹〜Ｒ³はそれぞれ独立に水素原子、ハロゲン原子、又は、一価の有機置換基を表す。ただし、Ｒ¹〜Ｒ³の少なくともいずれか１つは、アルコキシ基、メルカプト基、ハロゲン原子、アミド基、アセトキシ基、アミノ基、及び、イソプロペノキシ基よりなる群から選択される加水分解性基、又は、ヒドロキシ基を表す。）

(In Formula (B2-2) and Formula (B2-3), R ^B represents an ester bond, an amide bond, a urethane bond, a urea bond, or an imino group, L ¹ represents an n-valent linking group, and L ² represents a divalent linking group, L ^s1 represents an m-valent linking group, L ³ represents a divalent linking group, n and m each independently represents an integer of 1 or more, R ^{1 to} R ³ each independently represents a hydrogen atom, a halogen atom, or a monovalent organic substituent, provided that at least one of R ^{1 to} R ³ is an alkoxy group, a mercapto group, a halogen atom, an amide group, an acetoxy group A hydrolyzable group selected from the group consisting of a group, an amino group, and an isopropenoxy group, or a hydroxy group.)

R ¹ to R in the formula (B2-2) and formula (B2-3) ³ has the same meaning as R ¹ to R ³ in Formula (B 2 - 1), and preferred ranges are also the same.
Wherein R ^B is, from the viewpoint of rinsing properties and film strength, it is preferable that an ester bond or a urethane bond, and more preferably an ester bond.
The divalent or n-valent linking group in L ^{1 to} L ³ is a group composed of at least one atom selected from the group consisting of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom and a sulfur atom. It is preferably a group composed of at least one atom selected from the group consisting of carbon atom, hydrogen atom, oxygen atom and sulfur atom. The number of carbon atoms of L ^{1 to} L ³ is preferably 2 to 60, and more preferably 2 to 30.
The m-valent linking group in L ^s1 is a group composed of a sulfur atom and at least one atom selected from the group consisting of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom and a sulfur atom. Are preferable, and an alkylene group or a group in which two or more alkylene groups, sulfide groups, and imino groups are combined is more preferable. The carbon number of L ^s1 is preferably 2 to 60, and more preferably 6 to 30.
N and m are each independently preferably an integer of 1 to 10, more preferably an integer of 2 to 10, still more preferably an integer of 2 to 6, and particularly preferably 2. preferable.
The n-valent linking group of L ¹ and / or the divalent linking group of L ² or the divalent linking group of L ³ must have an ether bond from the viewpoint of sculpture residue removal (rinse). It is more preferable to have an ether bond contained in the oxyalkylene group.
Among the compounds represented by formula (B2-2) and formula (B2-3), from the viewpoint of crosslinkability and the like, in formula (B2-2), an n-valent linking group of L ¹ and / or L ² The divalent linking group is preferably a group having a sulfur atom.

  Specific examples of Component B2 that can be applied to the present invention are shown below. For example, vinyltrichlorosilane, 1,3-bis (trichlorosilane) propane, 1,3-bis (tribromosilane) propane, vinyltrimethoxysilane, vinyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyl Trimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, p-styryltrimethoxysilane , Γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminop Propylmethyldimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ- Aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, dimethoxy-3-mercaptopropylmethylsilane, 2 -(2-aminoethylthioethyl) diethoxymethylsilane, 3- (2-acetoxyethylthiopropyl) dimethoxymethylsilane, 2- (2-aminoethylthioethyl) triethoxysilane, dimethoxymethyl-3- (3- Phenoxypro Luthiopropyl) silane, bis (triethoxysilylpropyl) disulfide, bis (triethoxysilylpropyl) tetrasulfide, 1,4-bis (triethoxysilyl) benzene, bis (triethoxysilyl) ethane, 1,6-bis ( Trimethoxysilyl) hexane, 1,8-bis (triethoxysilyl) octane, 1,2-bis (trimethoxysilyl) decane, bis (triethoxysilylpropyl) amine, bis (trimethoxysilylpropyl) urea, γ- Examples include chloropropyltrimethoxysilane, γ-triethoxysilylpropyl (meth) acrylate, γ-ureidopropyltriethoxysilane, trimethylsilanol, diphenylsilanediol, and triphenylsilanol. In addition, the compounds shown below are preferred, but the present invention is not limited to these compounds.

In the above formulas, R represents a partial structure selected from the following structures. When a plurality of R and R ¹ are present in the molecule, these may be the same or different from each other, and are preferably the same in terms of synthesis suitability.

In the above formulas, R represents a partial structure shown below. R ¹ has the same meaning as described above. When a plurality of R and R ¹ are present in the molecule, these may be the same or different from each other, and are preferably the same in terms of synthesis suitability.

  Component B2 can be obtained by appropriately synthesizing, but it is preferable from the viewpoint of cost to use a commercially available product. As component B2, for example, commercially available silane products and silane coupling agents commercially available from Shin-Etsu Chemical Co., Ltd., Toray Dow Corning Co., Ltd., Momentive Performance Materials Co., Ltd., Chisso Co., Ltd., etc. Since products correspond to this, these commercially available products may be appropriately selected according to the purpose.

As the component B2 in the present invention, a partial hydrolysis condensate obtained by using one kind of compound having a hydrolyzable silyl group and / or silanol group, or a partial cohydrolysis condensate obtained by using two or more kinds Can be used. Hereinafter, these compounds may be referred to as “partial (co) hydrolysis condensates”.
Among silane compounds as partial (co) hydrolysis condensate precursors, from the viewpoint of versatility, cost, and film compatibility, it has a substituent selected from a methyl group and a phenyl group as a substituent on silicon. It is preferably a silane compound, specifically, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane. Is exemplified as a preferred precursor.
In this case, as a partial (co) hydrolysis condensate, dimers of the silane compound as described above (1 mol of water was allowed to act on 2 mol of the silane compound to remove 2 mol of alcohol to form disiloxane units. To 100-mer, preferably 2 to 50-mer, more preferably 2 to 30-mer, and a partial cohydrolysis condensate using two or more silane compounds as raw materials. It is also possible to use it.

  In addition, as such a partial (co) hydrolysis condensate, you may use what is marketed as a silicone alkoxy oligomer (for example, it is marketed from Shin-Etsu Chemical Co., Ltd.), etc. You may use what was manufactured by removing by-products, such as alcohol and hydrochloric acid, after making the hydrolysis water of less than an equivalent react with a hydrolysable silane compound based on a conventional method. In production, for example, when using alkoxysilanes or acyloxysilanes as described above as the precursor hydrolyzable silane compound, acids such as hydrochloric acid and sulfuric acid, sodium hydroxide, hydroxide Alkaline or alkaline earth metal hydroxides such as potassium, alkaline organic substances such as triethylamine, etc. may be used as a reaction catalyst for partial hydrolysis and condensation. In the case of direct production from chlorosilanes, by-product hydrochloric acid is used as a catalyst. And water and alcohol may be reacted.

  Component B2 may use only 1 type and may use 2 or more types together. The content of component B2 is preferably in the range of 0.1 to 80% by mass of the relief forming layer, more preferably in the range of 1 to 40% by mass, and most preferably 5 to 30 in terms of solid content. It is the range of mass%.

<(Component C) Polymer not containing amino group>
The relief forming layer of the relief printing plate precursor for laser engraving of the present invention preferably contains (Component C) a polymer containing no amino group. Component C is preferably a non-elastomer. The elastomer is a polymer having a glass transition temperature of room temperature or lower (see Science Dictionary 2nd edition, Editor International Science Promotion Foundation, published by Maruzen Co., Ltd., P154). Therefore, the non-elastomer refers to a polymer having a glass transition temperature exceeding normal temperature (20 ° C.). The glass transition temperature of the non-elastomer is preferably 20 to 200 ° C, more preferably 20 to 170 ° C, and still more preferably 25 to 150 ° C, from the viewpoint of the balance between engraving sensitivity and film property. When the component C having a glass transition temperature in the above range is combined with the (component F) photothermal conversion agent, engraving sensitivity is improved. Component C in the glassy state at room temperature is in a state in which thermal molecular motion is suppressed as compared with the rubbery state. In laser engraving, in addition to the heat imparted by laser irradiation, the heat generated by the function of the photothermal conversion agent used in combination is transmitted to the component C present in the surroundings, and the component C is thermally decomposed and dissipated, resulting in To form a recess. If a photothermal conversion agent is present in component C in which thermal molecular motion is suppressed, it is presumed that heat transfer and thermal decomposition to component C occur effectively and engraving sensitivity further increases.

  Component C is an effective component for imparting film properties during film formation. Component C is preferably a polymer compound selected from (meth) acrylic resin, vinyl acetal resin, urethane resin, amide resin, epoxy resin, styrene resin, ester resin, butyral resin, (meth) acrylic resin, styrene resin, A polyurethane resin and a butyral resin are more preferable, and a butyral resin is particularly preferable. Component C may be any of random polymer, block polymer, graft polymer and the like.

  As the butyral resin, polyvinyl butyral and its derivatives are preferable. Polyvinyl butyral is represented by the formula (C-1), and the derivative includes a repeating unit represented by the formula (C-1).

  In formula (C-1), l, m, and n represent the content (mol%) of each repeating unit in formula (C-1) in polyvinyl butyral, and satisfy the relationship of l + m + n = 100. The butyral content (value of 1 in the formula (C-1)) in polyvinyl butyral and its derivatives is preferably 30 to 90 mol%, more preferably 40 to 85 mol%, and particularly preferably 45 to 78 mol%.

  Specific examples of polyvinyl butyral and its derivatives are preferably Sekisui Chemical Co., Ltd. S-LEC B series, S-LEK K (KS) series, Denka Butyral manufactured by Denki Kagaku Kogyo Co., Ltd. As the S-Rec B series, BL-1, BL-1H, BL-2, BL-5, BL-S, BX-L, BM-S, BH-S, and Denkabutyral # 3000-1, # 3000 -2, # 3000-4, # 4000-2, # 6000-C, # 6000-EP, # 6000-CS, # 6000-AS.

Component C may have a crosslinkable group. Here, the crosslinkable group is a group having a function of crosslinking a polymer not containing an amino group. For example, an ethylenically unsaturated group, amino group, epoxy group, hydroxy group as a functional group capable of addition polymerization reaction. Etc. Moreover, the functional group which can become a radical by heat or light may be sufficient, and examples of such a crosslinkable group include a thiol group and a halogen atom. Among these, an ethylenically unsaturated bond group is preferable.
In Component C, for example, free radicals (polymerization initiation radicals or growth radicals in the polymerization process of a polymerizable compound) are added to the crosslinkable functional group, and addition polymerization is performed directly between polymers or via a polymerization chain of the polymerizable compound. As a result, a cross-link is formed between the polymer molecules and cured. Alternatively, atoms in the polymer (eg, hydrogen atoms on carbon atoms adjacent to the functional bridging group) are abstracted by free radicals to form polymer radicals that are bonded together, thereby causing cross-linking between polymer molecules. Forms and cures.

  From the viewpoint of balance between engraving sensitivity and film property, the weight average molecular weight of Component C is preferably 5,000 or more, and preferably 10,000 to 300,000. Further, the number average molecular weight is preferably 1,000 or more, and more preferably 2,000 to 250,000. The polydispersity (weight average molecular weight / number average molecular weight) is preferably 1.1 to 10.

  Component C may be used alone or in combination of two or more. The content of Component C is preferably from 5 to 75% by mass, more preferably from 10 to 70% by mass, based on the total solid content of the relief forming layer, from the viewpoint of good image area strength and image formability. -60 mass% is still more preferable.

(Component D) Plasticizer The relief forming layer of the relief printing plate precursor for laser engraving of the present invention preferably contains (Component D) a plasticizer from the viewpoint of imparting flexibility necessary for a flexographic plate. As the plasticizer, those known as polymer plasticizers can be used, and are not limited. For example, those described in pages 211 to 220 of Polymer Dictionary (First Edition, published by Maruzen Co., Ltd., 1994). Adipic acid derivatives, azelaic acid derivatives, benzoyl acid derivatives, citric acid derivatives, epoxy derivatives, glycol derivatives, hydrocarbons and derivatives, oleic acid derivatives, phosphoric acid derivatives, phthalic acid derivatives, polyesters, ricinoleic acid derivatives, sebacic acid derivatives, Examples include stearic acid derivatives, sulfonic acid derivatives, terpenes and derivatives, and trimellitic acid derivatives. Among these, adipic acid derivatives, citric acid derivatives, and phosphoric acid derivatives are preferable from the viewpoint of the effect of reducing the glass transition temperature.
As the adipic acid derivative, dibutyl adipate and 2-butoxyethyl adipate are preferable, and as the citric acid derivative, tributyl citrate is preferable. Examples of phosphoric acid derivatives include tributyl phosphate, tri-2-ethylhexyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, cresyl diphenyl phosphate, tricresyl phosphate, t-butylphenyl phosphate, 2-ethylhexyl phosphate Examples thereof include diphenyl and the like. Among them, triphenyl phosphate, cresyl diphenyl phosphate and tricresyl phosphate are preferable, and cresyl diphenyl phosphate is more preferable.
Component D may use only 1 type and may use 2 or more types together. From the viewpoint of lowering the glass transition temperature to room temperature or lower, the content of Component D is preferably 1 to 50% by mass, preferably 10 to 40% by mass, in terms of solid content, with the total mass of the relief forming layer being 100% by mass. Is more preferable, and 20-30 mass% is still more preferable.

(Component E) Polymerization initiator The relief forming layer of the relief printing plate precursor for laser engraving of the present invention preferably further contains (Component E) a polymerization initiator. As the polymerization initiator, a radical polymerization initiator is preferable, and compounds described in paragraphs 0074 to 0118 of JP-A-2008-63554 can be preferably exemplified.
As radical polymerization initiators, aromatic ketones, onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, carbon halogens Examples thereof include a compound having a bond and an azo compound.

  In particular, when the relief forming layer is thermally crosslinked, an organic peroxide or an azo compound is used from the viewpoint of engraving sensitivity and a relief edge shape being favorable when applied to the relief forming layer of the relief printing plate precursor. More preferred are organic peroxides. As the organic peroxide, those described in JP-A-2008-63554 and JP-A-2008-233244 are preferable, and among them, t-butylperoxybenzoate is preferable.

Moreover, it is preferable to use a combination of an organic peroxide and a photothermal conversion agent because the engraving sensitivity is extremely high, and an embodiment using a combination of an organic peroxide and carbon black as a photothermal conversion agent is more preferable. This is because when an organic peroxide is used to cure the relief forming layer by thermal crosslinking, unreacted organic peroxide that does not participate in radical generation remains, but the remaining organic peroxide is self-reactive. Works as an additive and decomposes exothermically during laser engraving. As a result, the amount of heat generated is added to the irradiated laser energy, so that the engraving sensitivity is estimated to increase.
This effect is remarkable when carbon black is used as the photothermal conversion agent. This is because the heat generated from the carbon black is transferred to the organic peroxide, resulting in heat generation not only from the carbon black but also from the organic peroxide, and generation of thermal energy to be used for decomposition of the component B and the like. This is considered to occur synergistically.

  In the case where the relief forming layer is photocrosslinked, aromatic ketones are preferred. As aromatic ketones, an α-hydroxyacetophenone compound is preferable, and a compound represented by Formula (E-1) is more preferable.

（式（Ｅ−１）中、Ｒ¹は水素原子、炭素数１〜１０のアルキル基、又は、炭素数１〜１０のアルコキシ基を表し、Ｒ²、Ｒ³は互いに独立して、水素原子、又は、炭素数１〜１０のアルキル基を表し、Ｒ²とＲ³とは結合して炭素数４〜８の環を形成していてもよい。）

(In Formula (E-1), R ¹ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and R ² and R ³ are each independently a hydrogen atom. Alternatively, it represents an alkyl group having 1 to 10 carbon atoms, and R ² and R ³ may be bonded to form a ring having 4 to 8 carbon atoms.)

  Examples of α-hydroxyacetophenones include 2-hydroxy-2-methyl-1-phenylpropan-1-one (DAROCUR 1173), 2-hydroxy-2-methyl-1-phenylbutan-1-one, 1- (4-methylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-isopropylphenyl) -2-methylpropan-1-one, 1- (4-butylphenyl) -2-hydroxy 2-methylpropan-1-one, 2-hydroxy-2-methyl-1- (4-octylphenyl) propan-1-one, 1- (4-dodecylphenyl) -2-methylpropan-1-one, 1- (4-methoxyphenyl) -2-methylpropan-1-one, 1- (4-methylthiophenyl) -2-methylpropan-1-one, 1- (4-Chlorophenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-bromophenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-1- (4- Hydroxyphenyl) -2-methylpropan-1-one, 1- (4-dimethylaminophenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-carboethoxyphenyl) -2-hydroxy- 2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone (IRGACURE 184), 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one (IRGACURE 2959).

A polymerization initiator may be used individually by 1 type, and can also use 2 or more types together.
The content of the polymerization initiator is preferably 0.01 to 10% by mass, and preferably 0.1 to 3% by mass with respect to the total solid content of the relief forming layer, from the viewpoint of curing speed and final film hardness adjustment. % Is more preferable.

(Component F) Photothermal Conversion Agent The relief forming layer of the relief printing plate precursor for laser engraving of the present invention preferably further contains a photothermal conversion agent. It is considered that the photothermal conversion agent promotes thermal decomposition of the cured product during laser engraving by absorbing laser light and generating heat. For this reason, it is preferable to select a photothermal conversion agent that absorbs light having a laser wavelength used for engraving.
When the relief printing plate precursor for laser engraving of the present invention is used for laser engraving using a laser (YAG laser, semiconductor laser, fiber laser, surface emitting laser, etc.) emitting infrared rays of 700 to 1,300 nm as a light source, a photothermal conversion agent It is preferable to use a compound having a maximum absorption wavelength at 700 to 1,300 nm. Various dyes or pigments are used as the photothermal conversion agent.

  Among the photothermal conversion agents, as the dye, commercially available dyes and known ones described in documents such as “Dye Handbook” (edited by the Society for Synthetic Organic Chemistry, published in 1970) can be used. Specific examples include those having a maximum absorption wavelength at 700 to 1,300 nm. Azo dyes, metal complex azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, diimonium compounds, quinone imine dyes Preferred are dyes such as methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal thiolate complexes. Dyes preferably used in the present invention include cyanine dyes such as heptamethine cyanine dyes, oxonol dyes such as pentamethine oxonol dyes, phthalocyanine dyes, and paragraphs 0124 to 0137 of JP-A-2008-63554. Mention may be made of dyes.

Among the photothermal conversion agents used in the present invention, commercially available pigments and color index (CI) manuals, “latest pigment manuals” (edited by the Japan Pigment Technical Association, published in 1977), “latest pigment application” The pigments described in "Technology" (CMC Publishing, 1986) and "Printing Ink Technology" (CMC Publishing, 1984) can be used. Examples of the pigment include pigments described in paragraphs 0122 to 0125 of JP-A-2009-178869.
Of these pigments, carbon black is preferred. As long as the dispersibility in the composition is stable, any carbon black can be used regardless of the application, in addition to the classification based on ASTM. Carbon black includes, for example, furnace black, thermal black, channel black, lamp black, acetylene black and the like. In order to facilitate dispersion, black colorants such as carbon black can be used as color chips or color pastes previously dispersed in nitrocellulose or a binder, if necessary. Such chips and pastes can be easily obtained as commercial products. Examples of carbon black include those described in paragraphs 0130 to 0134 of JP2009-178869A.

  The content of the photothermal conversion agent in the relief forming layer varies greatly depending on the molecular extinction coefficient inherent to the molecule, but is preferably 0.01 to 30% by mass of the total solid content of the relief forming layer, 0.05 -20 mass% is more preferable, and 0.1-10 mass% is especially preferable.

(Component G) The relief forming layer of the relief printing plate precursor for laser engraving of the present invention is preferably (Component G) the periodic table. And at least one oxy compound of a metal or metalloid selected from Group 1-16. The component G is not particularly limited as long as it is selected from Groups 1 to 16 of the periodic table, but is not limited to alkali metals (Li, Na, K, Rb, Cs, Fr), alkaline earth metals (Be, Mg). , Ca, Sr, Ba, Ra), aluminum, silicon, phosphorus, titanium, germanium, arsenic, zirconium, tin, zinc, cadmium, bismuth, indium, scandium and antimony are preferred. Preferred in terms of engraving sensitivity are alkaline earth metals, aluminum, silicon, phosphorus, bismuth, titanium, germanium, arsenic, zirconium, tin, zinc, more preferably alkaline earth metals, tin, zinc, bismuth, Zirconium, titanium (preferably valence 4), aluminum, particularly preferably alkaline earth metal, tin, bismuth, zinc, titanium and aluminum.
Examples of the oxy compound (= oxygen-containing compound) include alkoxides, phenoxides, enolates, carbonates, acetates or carboxylates and oxides of the above metals or metalloids.
If desired, the organic portion of the oxy compound can be partially polyvalent, such as those derived from polyhydric alcohols (eg, glycol or glycerol), polyvinyl alcohol, or hydroxycarboxylic acids. Chelate compounds may be used. When carbon atoms are present, typically the number of carbon atoms per metal or metalloid ranges from 4 to 24.
In the present invention, zinc, tin, bismuth, and aluminum carboxylates are preferable, and among them, zinc acetate, zinc 2-ethylhexanoate, tin 2-ethylhexanoate, bismuth tris (2-ethylhexanoate), bis (2 -Ethylhexanoic acid) hydroxyaluminum is particularly preferred.
The content of component G is preferably 0.01 to 20% by mass, more preferably 0.5 to 10% by mass, with the total mass of the relief forming layer being 100% by mass from the viewpoint of engraving sensitivity and film property. 5 mass% is still more preferable.

(Other ingredients)
In addition to Component A to Component G, the relief forming layer of the relief printing plate precursor for laser engraving of the present invention can be used in combination with various compounds depending on the purpose as long as the effects of the present invention are not impaired. In addition to the above components A and B, a known binder polymer can be used in combination in the relief forming layer. For example, from the viewpoint of laser engraving sensitivity, a polymer containing a partial structure that is thermally decomposed by exposure or heating is preferable. In addition, for example, when a soft and flexible film formation is intended, a soft resin is selected. Furthermore, it is preferable to use a hydrophilic or alcoholic polymer from the viewpoint of ease of preparation of the relief forming layer and improvement of resistance to oil-based ink in the obtained relief printing plate. These components are described in JP2008-163081A.

In addition, polyesters composed of hydroxycarboxylic acid units such as polylactic acid can be preferably used. Specific examples of such polyester include polyhydroxyalkanoate (PHA), lactic acid-based polymer, polyglycolic acid (PGA), polycaprolactone (PCL), poly (butylene succinic acid), and derivatives or mixtures thereof. Those selected from the group consisting of
In addition, when used for the purpose of curing by heating or exposure and improving the strength, a polymer having a carbon-carbon unsaturated bond in the molecule is preferably used. Examples of the polymer containing a carbon-carbon unsaturated bond in the main chain include SB (polystyrene-polybutadiene), SBS (polystyrene-polybutadiene-polystyrene), SIS (polystyrene-polyisoprene-polystyrene), SEBS (polystyrene-polyethylene / polybutylene). -Polystyrene) and the like.
The polymer having a carbon-carbon unsaturated bond in the side chain is a carbon-carbon unsaturated group such as an allyl group, an acryloyl group, a methacryloyl group, a styryl group, or a vinyl ether group in the skeleton of the binder polymer applicable in the present invention. It is obtained by introducing a bond into the side chain.
Thus, in consideration of the physical properties according to the application application of the relief printing plate, a binder polymer can be selected according to the purpose, and one or more of the binder polymers can be used in combination.

  In the relief forming layer of the relief printing plate precursor for laser engraving of the present invention, various additives usually used in the field of rubber can be appropriately blended as long as the effects of the present invention are not impaired. Examples include vulcanizing agents, fillers, waxes, process oils, organic acids, metal oxides, antiozonants, antiaging agents, thermal polymerization inhibitors, colorants, etc., and these are used alone. Alternatively, two or more kinds may be used in combination.

When process oil is used, for example, aromatic process oil, naphthenic process oil, and paraffinic process oil can be mentioned. The amount added is preferably 1 to 70 parts by mass per 100 parts by mass of component B.
The organic acid can be used as an auxiliary agent for vulcanization acceleration in combination with a conventional vulcanizing agent as a metal salt. Examples of the organic acid include stearic acid, oleic acid, and murastic acid. Examples of the metal source used in combination include metal oxides such as zinc oxide (zinc white) and magnesium oxide. In these vulcanization processes, organic acids and metal oxides form metal salts in the rubber, and the activation of vulcanizing agents such as sulfur is promoted. The amount of the metal oxide added to form such a metal salt in the system is preferably 0.1 to 10 parts by mass and more preferably 2 to 10 parts by mass per 100 parts by mass of the rubber component (component B). 0.1-5 mass parts is preferable per 100 mass parts of rubber components (component B), and, as for the addition amount of an organic acid, 0.1-3 mass parts is more preferable.

  In the present invention, the relief forming layer preferably contains an alcohol exchange reaction catalyst in order to promote the formation of a crosslinked structure of component B2. The alcohol exchange reaction catalyst can be applied without limitation as long as it is a reaction catalyst generally used in a silane coupling reaction. Hereinafter, the acid or basic catalyst which is a typical alcohol exchange reaction catalyst will be sequentially described.

As the catalyst, it is preferable to use an acid or a basic compound as it is, or a catalyst dissolved in water or a solvent such as an organic solvent (hereinafter also referred to as an acidic catalyst or a basic catalyst, respectively). The concentration at the time of dissolving in the solvent is not particularly limited, and may be appropriately selected according to the characteristics of the acid or basic compound used, the desired content of the catalyst, and the like.
Acidic catalysts include hydrogen halides such as hydrochloric acid, nitric acid, sulfuric acid, sulfurous acid, hydrogen sulfide, perchloric acid, hydrogen peroxide, carbonic acid, carboxylic acids such as formic acid and acetic acid, and R of the structural formula represented by RCOOH. Examples thereof include substituted carboxylic acids substituted with other elements or substituents, sulfonic acids such as benzenesulfonic acid, phosphoric acid, heteropolyacid, and inorganic solid acids.
Examples of the basic catalyst include ammoniacal bases such as aqueous ammonia, amines, alkali metal hydroxides, alkali metal alkoxides, alkaline earth oxides, quaternary ammonium salt compounds, quaternary phosphonium salt compounds, and the like.

Examples of amines include (a) hydrazine compounds such as hydrazine; (b) aliphatic amines, alicyclic amines or aromatic amines; (c) cyclic amines containing condensed rings; (d) amino acids and amides. Oxygen-containing amines such as alcohol amines, ether amines, imides or lactams; (e) hetero-containing amines having a hetero atom such as S and Se;
As the aliphatic amine (b), an amine compound represented by the formula (D-1) is preferable.
N (R ^d1 ) (R ^d2 ) (R ^d3 ) (D-1)
In formula (D-1), R ^{d1 to} R ^d3 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, or 6 to 6 carbon atoms. 20 represents an aryl group, a heterocyclic ring (thiophene) containing a sulfur atom or oxygen atom having 3 to 10 ring members, and the alkyl group and cycloalkyl group may have at least one unsaturated bond.
The amine compound represented by the formula (D-1) may have a substituent, and examples of the substituent include an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an amino group, Examples thereof include (di) alkylamino groups and hydroxy groups having an alkyl group having 1 to 6 carbon atoms.
Two or more groups of R ^{d1 to} R ^d3 may be bonded to form a C═N bond. Examples of the amine compound having a C═N bond include guanidine and 1,1,3,3-tetramethylguanidine.
As the alicyclic amine of (b), an alicyclic compound containing a nitrogen atom in a ring skeleton in which two or more groups out of R ^{d1 to} R ^d3 in the compound represented by the formula (D-1) are bonded. Examples include amines. Examples of the alicyclic amine include pyrrolidine, piperidine, piperazine, and quinuclidine.
Examples of the aromatic amine (b) include imidazole, pyrrole, pyridine, pyridazine, pyrazine, purine, quinoline, and quinazoline. The aromatic amine may have a substituent, and examples of the substituent include the substituent in formula (D-1).
Further, two or more aliphatic amines, alicyclic amines, and aromatic amines that are the same or different may be combined to form a polyamine such as diamine or triamine. The polyamine is preferably a polyamine in which aliphatic amines are bonded to each other, and examples thereof include hexamethylenetetramine and polyethyleneimine (Epomin, manufactured by Nippon Shokubai Co., Ltd.).

The (c) cyclic amine containing a condensed ring is a cyclic amine containing a ring skeleton in which at least one nitrogen atom forms a condensed ring. For example, 1,8-diazabicyclo [5.4.0] undeca- 7-ene, 1,5-diazabicyclo [4.3.0] non-5-ene, 1,4-diazabicyclo [2.2.2] octane, among others, 1,8-diazabicyclo [5.4]. 0.0] Undec-7-ene is preferred.
Examples of the oxygen-containing amines such as (d) amino acids, amides, alcohol amines, ether amines, imides or lactams include phthalimide, 2,5-piperazinedione, maleimide, caprolactam, pyrrolidone, morpholine, glycine, Examples include alanine and phenylalanine.
In addition, (c) and (d) may have the said substituent in the compound represented by Formula (D-1), and a C1-C6 alkyl group is especially preferable.
In the present invention, the amine compound is preferably (b) or (c). (B) is preferably an aliphatic amine, more preferably an aliphatic amine polyamine, and still more preferably polyethyleneimine. (C) is preferably 1,8-diazabicyclo [5.4.0] undec-7-ene.

From the viewpoint of film strength after thermal crosslinking, the preferable range of pKaH (acid dissociation constant of conjugate acid) as an amine is preferably 7 or more, more preferably 10 or more.
Among the acid or basic catalysts, methanesulfonic acid, p-toluenesulfonic acid, pyridinium p-toluenesulfonate, dodecylbenzenesulfonic acid, phosphoric acid, phosphonic acid are used from the viewpoint of promptly proceeding the alcohol exchange reaction in the membrane. , Acetic acid, polyethyleneimine, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,5-diazabicyclo [4.3.0] non-5-ene, 1,1,3,3- Tetramethylguanidine is preferable, and phosphoric acid, polyethyleneimine, and 1,8-diazabicyclo [5.4.0] undec-7-ene are particularly preferable.

  In the present invention, only one alcohol exchange reaction catalyst may be used, or two or more kinds may be used in combination. The content of the alcohol exchange reaction catalyst in the relief forming layer is preferably 0.01 to 20% by mass and more preferably 0.1 to 10% by mass in the total solid content of the relief forming layer.

(Relief printing plate precursor for laser engraving)
The relief printing plate precursor for laser engraving of the first embodiment has a relief forming layer containing the above components. The relief printing plate precursor for laser engraving of the second embodiment has a crosslinked relief forming layer obtained by crosslinking the relief forming layer. The crosslinking is preferably performed by heat and / or light, and more preferably by heat. Moreover, the said bridge | crosslinking will not be specifically limited if it is reaction by which a relief formation layer is hardened, It is a concept containing the crosslinked structure by reaction of component B1 or component B2.

A “relief printing plate” is produced by laser engraving a relief printing plate precursor for laser engraving having a crosslinked relief forming layer. The “relief layer” refers to a layer engraved with a laser in a relief printing plate, that is, the crosslinked relief forming layer after laser engraving.
The relief printing plate precursor for laser engraving of the present invention has a relief forming layer containing the above components. The (crosslinked) relief forming layer is preferably provided on the support. The relief printing plate precursor for laser engraving further has an adhesive layer between the support and the (crosslinked) relief forming layer, if necessary, and a slip coat layer and a protective film on the (crosslinked) relief forming layer. May be.

<Relief forming layer>
The relief printing plate precursor for laser engraving of the present invention has a relief-forming layer imparted with a crosslinkable function by Component B1 or Component B2.
As a production mode of a relief printing plate using a relief printing plate precursor for laser engraving, a relief printing plate precursor having a crosslinked relief forming layer is obtained by crosslinking the relief forming layer, and then a crosslinked relief forming layer (hard relief forming layer) is used. An embodiment in which a relief layer is formed by laser engraving to form a relief printing plate is preferred. By crosslinking the relief forming layer, wear of the relief layer during printing can be prevented, and a relief printing plate having a relief layer having a sharp shape after laser engraving can be obtained.

  The relief forming layer is formed by molding a resin composition containing the above components for the relief forming layer into a sheet shape or a sleeve shape. The relief forming layer is usually provided on a support which will be described later. However, the relief forming layer can be directly formed on the surface of a member such as a cylinder provided in an apparatus for plate making and printing, or can be arranged and fixed there. It does not necessarily require a support. Hereinafter, the case where the relief forming layer is formed into a sheet shape will be mainly described as an example.

<Support>
The material used for the support of the relief printing plate precursor for laser engraving is not particularly limited, but materials having high dimensional stability are preferably used. For example, metals such as steel, stainless steel and aluminum, polyester (for example, PET (polyethylene terephthalate)) , Plastic resins such as PBT (polybutylene terephthalate), PAN (polyacrylonitrile)) and polyvinyl chloride, synthetic rubbers such as styrene-butadiene rubber, and plastic resins reinforced with glass fibers (such as epoxy resins and phenol resins) It is done. As the support, a PET film or a steel substrate is preferably used. The form of the support is determined depending on whether the relief forming layer is a sheet or a sleeve.

<Adhesive layer>
When the relief forming layer is formed on the support, an adhesive layer may be provided between them for the purpose of enhancing the adhesive strength between the layers. As a material (adhesive) that can be used for the adhesive layer, for example, I.I. Those described in the edition of Skeist, “Handbook of Adhesives”, the second edition (1977) can be used.

<Protective film, slip coat layer>
For the purpose of preventing scratches or dents on the surface of the relief forming layer or the surface of the crosslinked relief forming layer, a protective film may be provided on the surface of the relief forming layer or the surface of the crosslinked relief forming layer. The thickness of the protective film is preferably 25 to 500 μm, more preferably 50 to 200 μm. As the protective film, for example, a polyester film such as PET, or a polyolefin film such as PE (polyethylene) or PP (polypropylene) can be used. The surface of the film may be matted. The protective film is preferably peelable.
When the protective film cannot be peeled or when it is difficult to adhere to the relief forming layer, a slip coat layer may be provided between both layers. The material used for the slip coat layer is a resin that can be dissolved or dispersed in water, such as polyvinyl alcohol, polyvinyl acetate, partially saponified polyvinyl alcohol, hydroxyalkyl cellulose, alkyl cellulose, polyamide resin, etc. It is preferable that

(Manufacturing method of relief printing plate precursor for laser engraving)
Formation of the relief forming layer in the relief printing plate precursor for laser engraving is not particularly limited. For example, after preparing a resin composition containing each component and removing the solvent from the resin composition, the support is prepared. The method of melt-extruding above is mentioned. Alternatively, a method may be used in which a resin composition containing each component is cast on a support and dried in an oven to remove the solvent from the resin composition.
Among them, the method for producing a relief printing plate precursor for laser engraving of the present invention includes a layer forming step of forming a relief forming layer comprising a resin composition containing each component, and a crosslinked relief forming layer by thermally crosslinking the relief forming layer. It is preferable that the production method includes a cross-linking step of obtaining a relief printing plate precursor having

  Thereafter, a protective film may be laminated on the relief forming layer as necessary. Lamination can be performed by pressure-bonding the protective film and the relief forming layer with a heated calendar roll or the like, or by bringing the protective film into close contact with the relief forming layer impregnated with a small amount of solvent on the surface. When using a protective film, you may take the method of laminating | stacking a relief forming layer on a protective film first, and laminating a support body then. When providing an adhesive layer, it can respond by using the support body which apply | coated the adhesive layer. When providing a slip coat layer, it can respond by using the protective film which apply | coated the slip coat layer.

<Layer formation process>
The method for producing a relief printing plate precursor for laser engraving of the present invention preferably includes a layer forming step of forming a relief forming layer made of the resin composition for laser engraving containing each of the above components. As a method for forming the relief forming layer, a resin composition containing each component is prepared, and if necessary, after removing the solvent from the resin composition, a method of melt extrusion on a support, or a resin composition is used. A method of preparing and casting the resin composition on a support and drying it in an oven to remove the solvent can be preferably exemplified.

  The resin composition can be produced, for example, by dissolving Component A, Component B, and other optional components in an appropriate solvent, and then dissolving Component B1, Component B2, and a polymerization initiator. It is preferable to use an amount of solvent such that the viscosity of the resin composition is 10 to 200 poise. For the stirring and mixing, any method suitable for mixing a liquid having the above viscosity range can be used, but mixing with a static mixer or a dynamic mixer is particularly preferable. Most of the solvent component needs to be removed at the stage of producing the relief printing plate precursor. It is preferable to use a solvent that easily volatilizes and suppress the total amount of the solvent as small as possible by adjusting the temperature.

  The thickness of the (crosslinked) relief forming layer in the relief printing plate precursor for laser engraving is preferably 0.05 to 10 mm, more preferably 0.05 to 7 mm, and still more preferably 0.05 to 3 mm before and after crosslinking.

<Crosslinking process>
The plate making method of the relief printing plate for laser engraving of the present invention is preferably a plate making method comprising a crosslinking step of obtaining a relief printing plate precursor having a crosslinked relief forming layer by thermally crosslinking or photocrosslinking the relief forming layer. The relief forming layer can be crosslinked by heating or irradiating the relief printing plate precursor for laser engraving (step of crosslinking by heat or light). Examples of the heating means for crosslinking by heat include a method of heating the printing plate precursor in a hot air oven or a far infrared oven for a predetermined time, and a method of contacting a heated roll for a predetermined time.
Examples of irradiation means for performing crosslinking with light (active radiation) include a mercury lamp, a metal halide lamp, an LED (UV-LED), and an LD (UV-LD). As the actinic radiation, α rays, γ rays, electron beams, X rays, ultraviolet rays, visible light, infrared light, or the like is used, and among these, ultraviolet rays are preferable. The exposure surface illuminance, 500~4,000mW / cm ^2, preferably, 1,000~3,000mW / cm ² is more preferable.
By heat-crosslinking or photocrosslinking the relief-forming layer, first, the relief formed after laser engraving becomes sharp, and secondly, the adhesiveness of engraving residue generated during laser engraving is suppressed. is there.

(Relief printing plate and plate making method)
The plate making method of the relief printing plate of the present invention comprises (1) a step of crosslinking the relief forming layer in the relief printing plate precursor for laser engraving with heat and / or light (crosslinking step), and (2) a crosslinked relief. A step of engraving the formation layer by laser engraving to form a relief layer (engraving step).

  The relief printing plate of the present invention is a relief printing plate having a relief layer obtained by crosslinking and laser engraving a relief forming layer containing each component, and the relief printing made by the plate making method of the relief printing plate of the present invention A plate is preferred. The relief printing plate of the present invention can be suitably used during printing with water-based ink. The layer forming step and the cross-linking step in the plate making method of the relief printing plate of the present invention are synonymous with the layer forming step and the cross-linking step in the plate making method of the relief printing plate precursor for laser engraving, and the preferred range is also the same.

<Engraving process>
The plate making method of the relief printing plate of the present invention preferably includes an engraving step of laser engraving the relief printing plate precursor having the crosslinked relief forming layer. The engraving step is a step of forming a relief layer by laser engraving the crosslinked relief forming layer crosslinked in the crosslinking step. Specifically, it is preferable to form a relief layer by engraving a crosslinked crosslinked relief forming layer by irradiating a laser beam corresponding to a desired image. Moreover, the process of controlling a laser head with a computer based on the digital data of a desired image and carrying out scanning irradiation with respect to a bridge | crosslinking relief forming layer is mentioned preferably.
In this engraving process, an infrared laser is preferably used. When irradiated with an infrared laser, the molecules in the crosslinked relief forming layer undergo molecular vibrations and generate heat. When a high-power laser such as a carbon dioxide laser or YAG laser is used as an infrared laser, a large amount of heat is generated in the laser irradiation part, and molecules in the crosslinked relief forming layer are selectively cut by molecular cutting or ionization. That is, engraving is performed. The advantage of laser engraving is that the engraving depth can be set arbitrarily, so that the structure can be controlled three-dimensionally. For example, the portion that prints fine halftone dots can be engraved shallowly or with a shoulder so that the relief does not fall down due to printing pressure, and the portion of the groove that prints fine punched characters is engraved deeply As a result, the ink is less likely to be buried in the groove, and the collapsed characters can be suppressed. In particular, when engraving with an infrared laser corresponding to the absorption wavelength of the photothermal conversion agent, the crosslinked relief forming layer can be selectively removed with higher sensitivity, and a relief layer having a sharp image can be obtained.

As the infrared laser used in the engraving process, a carbon dioxide laser (CO ₂ laser) or a semiconductor laser is preferable from the viewpoints of productivity and cost. In particular, a semiconductor infrared laser with a fiber (FC-LD) is preferably used. In general, a semiconductor laser is more efficient and cheaper than a CO ₂ laser and can be miniaturized, and since it is small, it can be easily arrayed. Furthermore, the beam shape can be controlled by processing the fiber.
The semiconductor laser preferably has a wavelength of 700 to 1,300 nm, more preferably 800 to 1,200 nm, still more preferably 860 to 1,200 nm, and particularly preferably 900 to 1,100 nm.

The semiconductor laser is effective for the engraving process because it can efficiently output laser light by attaching an optical fiber. Furthermore, the beam shape can be controlled by processing the fiber. For example, the beam profile can have a top hat shape, and energy can be stably given to the plate surface. Details of the semiconductor laser are described in “Laser Handbook 2nd Edition” edited by the Laser Society, practical laser technology, and the Institute of Electronics and Communication Engineers of Japan.
Also, a plate making apparatus equipped with a fiber-coupled semiconductor laser that can be suitably used in a method for making a relief printing plate using the relief printing plate precursor of the present invention is disclosed in JP 2009-172658 A and JP 2009-214334 A. And can be used for making a relief printing plate according to the present invention.

<Rinse process>
The plate making method of the relief printing plate of the present invention includes a rinsing step of rinsing engraving residue remaining on the surface of the relief layer after the engraving step using an acidic liquid (hereinafter also referred to as “rinsing liquid”). preferable.
Examples of the rinsing means include a means for immersing in an acidic liquid or a means for spraying an acidic liquid on the plate surface. If necessary, it is preferable to use a method of brushing the relief layer surface with a known batch type or conveying type brush type washing machine as a developing machine.

After the rinsing step, it is preferable to add a running step of washing the relief forming layer with running water, and a drying step of drying the engraved relief forming layer to volatilize the rinsing liquid.
Furthermore, you may add the post-crosslinking process which further bridge | crosslinks a relief forming layer as needed. By performing the post-crosslinking step, which is an additional cross-linking step, the relief formed by engraving can be further strengthened.

The pH of the rinse liquid is preferably 1.0 to 7.0, preferably 1.0 to 4.0, and more preferably 1.0 to 3.0 from the viewpoint of removability.
What is necessary is just to adjust pH using an acid and / or a base suitably in order to make a rinse liquid into said pH range, and the acid and base to be used are not specifically limited. Acids used to prepare the acidic rinse liquid include inorganic acids such as sulfuric acid, hydrochloric acid, or phosphoric acid, or organic acids such as acetic acid, trifluoroacetic acid, oxalic acid, methanesulfonic acid, or trifluoromethanesulfonic acid. Although it is mentioned, Preferably it is an inorganic acid, More preferably, it is a sulfuric acid.

  In addition to the acid, the rinsing liquid may contain a surfactant, a wetting agent, a preservative, a chelate compound, an antifoaming agent, an organic solvent, and the like as necessary.

  In the present invention, a surfactant may be added to the rinsing liquid for reasons such as improving the compatibility of the liquid, adjusting the liquid viscosity, improving the wettability to the plate, and removing the engraving residue. Typical examples of the surfactant that can be added to the rinsing liquid are illustrated, but the present invention is not limited to the following examples. Examples of the surfactant include those described in JP-A Nos. 62-173463 and 62-183457. For example, anionic surfactants such as dialkylsulfosuccinates, alkylnaphthalenesulfonates, fatty acid salts, polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols, polyoxyethylene / polyoxypropylene blocks Nonionic surfactants such as copolymers, and cationic surfactants such as alkylamine salts and quaternary ammonium salts.

  As the wetting agent, ethylene glycol, propylene glycol, triethylene glycol, butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, diglycerin and the like are preferably used. These wetting agents may be used alone or in combination of two or more. Generally, the wetting agent is used in an amount of 0.1 to 5% by weight based on the total weight of the rinse solution.

Preservatives include phenol or derivatives thereof, formalin, imidazole derivatives, sodium dehydroacetate, 4-isothiazolin-3-one derivatives, benzoisothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, benztriazole derivatives Amiding anidine derivatives, quaternary ammonium salts, derivatives such as pyridine, quinoline, guanidine, diazine, triazole derivatives, oxazole, oxazine derivatives, nitrobromoalcohol-based 2-bromo-2-nitropropane-1,3diol, 1, 1-dibromo-1-nitro-2-ethanol, 1,1-dibromo-1-nitro-2-propanol and the like can be preferably used.
The addition amount of the preservative is an amount that exerts stability against bacteria, molds, yeasts, etc., and varies depending on the types of bacteria, molds, yeasts, but is 0. The range of 01 to 4% by mass is preferable, and it is preferable to use two or more preservatives in combination so as to be effective against various molds and sterilization.

Examples of the chelate compound include ethylenediaminetetraacetic acid, potassium salt thereof, sodium salt thereof; diethylenetriaminepentaacetic acid, potassium salt thereof, sodium salt thereof; triethylenetetraminehexaacetic acid, potassium salt thereof, sodium salt thereof, hydroxyethylethylenediaminetriacetic acid Nitrilotriacetic acid, sodium salt; 1-hydroxyethane-1,1-diphosphonic acid, potassium salt, sodium salt; aminotri (methylenephosphonic acid), potassium salt, sodium salt And organic phosphonic acids and phosphonoalkanetricarboxylic acids. Organic amine salts are also effective in place of the sodium and potassium salts of the chelating agents.
These chelating agents are selected so that they exist stably in the treatment liquid composition and do not impair the printability. The addition amount is preferably 0.001 to 1.0% by mass with respect to the treatment liquid during use.

As the antifoaming agent, a general silicon-based self-emulsifying type, emulsifying type, surfactant nonionic type, HLB 5 or less compound can be used, and among them, a silicon-based antifoaming agent is preferable. Among them, emulsification dispersion type and solubilization can be used.
The content of the antifoaming agent is preferably in the range of 0.001 to 1.0% by mass with respect to the treatment liquid during use.

  The rinse liquid preferably contains water as a main component, but may contain an organic solvent as a solvent other than water. Examples of the organic solvent include aliphatic hydrocarbons (hexane, heptane, “Isopar E, H, G” (produced by Esso Chemical Co., Ltd.) or gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, etc.) ), Or halogenated hydrocarbons (methylene dichloride, ethylene dichloride, tricrene, monochlorobenzene, etc.) and polar solvents.

Polar solvents include alcohols (methanol, ethanol, propanol, isopropanol, benzyl alcohol, ethylene glycol monomethyl ether, 2-ethoxyethanol, diethylene glycol monoethyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl ether, propylene glycol monoethyl ether , Propylene glycol monomethyl ether, polyethylene glycol monomethyl ether, polypropylene glycol, tetraethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monobenzyl ether, ethylene glycol monophenyl ether, methylphenyl carbinol, n-amyl alcohol, methyl amyl alcohol, etc.) , (Acetone, methyl ethyl ketone, ethyl butyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), esters (ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, methyl lactate, butyl lactate, ethylene glycol monobutyl acetate, propylene Glycol monomethyl ether acetate, diethylene glycol acetate, diethyl phthalate, butyl levulinate, etc.) and others (triethyl phosphate, tricresyl phosphate, N-phenylethanolamine, N-phenyldiethanolamine, etc.).
In addition, when the organic solvent is insoluble in water, it can be used after being solubilized in water by using a surfactant or the like. From the viewpoint of properties, the solvent concentration is preferably less than 40% by mass.

  The rinse liquid is obtained by dissolving or dispersing each of the above components in a solvent as necessary. The solid content concentration of the rinse liquid is preferably 2 to 25% by mass. As the solvent, water is preferable.

  As described above, a relief printing plate having a relief layer on the surface of an arbitrary substrate such as a support can be obtained. The thickness of the relief layer of the relief printing plate is preferably 0.05 to 10 mm, more preferably 0.05 to 7 mm, from the viewpoint of satisfying various printability such as abrasion resistance and ink transferability. Especially preferably, it is 0.05-3 mm.

Moreover, it is preferable that the Shore A hardness of the relief layer which a relief printing plate has is 50-90 degrees. When the Shore A hardness of the relief layer is 50 ° or more, even if the fine halftone dots formed by engraving are subjected to the strong printing pressure of the relief printing press, they do not collapse and can be printed normally. In addition, when the Shore A hardness of the relief layer is 90 ° or less, it is possible to prevent faint printing in a solid portion even in flexographic printing with a kiss touch.
In addition, the Shore A hardness in this specification is a durometer (spring) in which an indenter (called a push needle or an indenter) is pressed and deformed on the surface of the object to be measured, and the amount of deformation (indentation depth) is measured and digitized. It is a value measured by a formula rubber hardness meter.

  The relief printing plate of the present invention is particularly suitable for printing with water-based ink by a flexographic printing machine, but printing is possible with any of water-based ink, oil-based ink and UV ink by a relief printing press. In addition, printing with UV ink by a flexographic printing machine is also possible. The relief printing plate of the present invention has excellent rinsing properties, no engraving residue remains, and the resulting relief layer is excellent in elasticity, so that it is excellent in water-based ink transfer and printing durability, and has a relief layer over a long period of time. Thus, printing can be carried out without concern for plastic deformation or deterioration of printing durability.

  Hereinafter, the present invention will be described in detail with reference to examples. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.

The structural formulas or compound names of Component A to Component F used in Examples and Comparative Examples are shown below.
(Component A) Polymer containing amino group The compounds shown in Table 1 were added.

<(Component B1) ethylenically unsaturated compound>

<(Component B2) Compound having hydrolyzable silyl group and / or silanol group>
B2-1: KBE-846 (manufactured by Shin-Etsu Chemical Co., Ltd.)

<(Component C) Polymer not containing amino group>
C-1: Polyvinyl butyral (Denka butyral # 3000-2, weight average molecular weight: 90,000, manufactured by Denki Kagaku Kogyo Co., Ltd.)
<(Component D) Plasticizer>
D-1: Cresyl diphenyl phosphate <(Component E) polymerization initiator>
E-1: Perbutyl Z (t-butyl peroxybenzoate, manufactured by NOF Corporation)
E-2: Irgacure 184 (α-hydroxyketone, manufactured by Ciba Specialty Chemicals)
<(Component F) photothermal conversion agent>
F-1: Ketjen Black EC600JD (carbon black, manufactured by Lion Corporation)
<(Component G) Other components>
G-1: Zinc 2-ethylhexylate (manufactured by Hope Pharmaceutical Co., Ltd.)
G-2: DBU (1,8-diazabicyclo [5.4.0] undec-7-ene, manufactured by San Apro Co., Ltd.)

Example 1
<Preparation of relief printing plate precursor 1 for laser engraving>
(C-1) 35 parts of polyvinyl butyral, 5 parts of the compound shown in Table 1 as component A, (D-1) 25 parts of cresyl diphenyl phosphate, (G-1) 2 parts of zinc 2-ethylhexylate, as a solvent 100 parts of propyl glycol monoethyl ether acetate (PGMEA) was placed in a three-necked flask equipped with a stirring blade and a condenser, and heated and dissolved at 70 ° C. for 120 minutes with stirring. Thereafter, 10 parts of ethylenically unsaturated compound (B1-1) and 3 parts of (F-1) ketjen black EC600JD were added and stirred for 30 minutes. Thereafter, 20 parts of (B2-1) KBE-846, 1.6 parts of (E-1) perbutyl Z, and 0.8 parts of (G-2) DBU were added and stirred at 70 ° C. for 10 minutes. By this operation, a fluid resin composition for laser engraving was obtained. A spacer (frame) with a predetermined thickness is placed on the PET substrate, and the resin composition for laser engraving is gently cast so that it does not flow out of the spacer (frame), and is dried and thermally crosslinked in an oven at 100 ° C. for 3 hours. Then, a relief forming layer having a thickness of about 1 mm was provided to prepare a relief printing plate precursor 1 for laser engraving.

(Examples 2 to 15)
<Preparation of relief printing plate precursors 2 to 15 for laser engraving>
Relief printing plate precursors 2 to 15 for laser engraving are produced in the same manner as in the relief printing plate precursor 1 for laser engraving of Example 1 except that the components A to C are changed to the types and blending amounts shown in Table 1. did.

(Example 16)
<Preparation of relief printing plate precursor 16 for laser engraving>
(C-1) 35 parts of polyvinyl butyral, 5 parts of the compound shown in Table 1 as component A, (D-1) 25 parts of cresyl diphenyl phosphate, (G-1) 2 parts of zinc 2-ethylhexylate, as a solvent 100 parts of propyl glycol monoethyl ether acetate (PGMEA) was placed in a three-necked flask equipped with a stirring blade and a condenser, and heated and dissolved at 70 ° C. for 120 minutes with stirring.
Thereafter, 10 parts of ethylenically unsaturated compound (B1-1) was further added and stirred for 30 minutes. Thereafter, 1.6 parts of (E-2) Irgacure 184 was added and stirred at 70 ° C. for 10 minutes. By this operation, a fluid resin composition for laser engraving was obtained.
A spacer (frame) with a predetermined thickness is placed on the PET substrate, and the resin composition for laser engraving is gently cast so as not to flow out of the spacer (frame), and is dried in an oven at 80 ° C. for 3 hours, and then air-dried. After that, using an exposure machine using a metal halide lamp manufactured by Ushio Co., Ltd., exposure was performed so that the exposure amount on the plate surface was 2,000 mJ / cm ² , and the relief printing plate precursor 16 for laser engraving was obtained. Produced.

(Comparative Examples 1-3)
<Preparation of relief printing plate precursors C1 to C3 for laser engraving>
Except that component A to component C are changed to the types and blending amounts shown in Table 1, laser relief engraving relief printing plate precursors C1 to C3 are prepared in the same manner as in laser engraving relief printing plate precursor 1 of Example 1. did.

<Preparation of relief printing plate for laser engraving>
As a laser engraving machine, ADFLEX (manufactured by Comtex) was used.
After peeling off the protective film from the printing plate precursor for laser engraving, a halftone dot pattern (2 × 2 dots, high with the laser engraving machine under the conditions of output: 12 W, head speed: 200 mm / second, pitch setting: 2,400 DPI 300 μm) was engraved.

(Debris removal)
A 1N aqueous solution of H ₂ SO ₄ (manufactured by Wako Pure Chemical Industries, Ltd.) was dropped into 500 ml of pure water while stirring, and the pH shown in Table 1 was adjusted to prepare a rinse solution.
The rinse solution prepared on each plate material engraved by the above method is dropped with a dropper (about 100 ml / m ² ) so that the plate surface is evenly wetted, and left for 1 minute, and then a toothbrush (Lion Corporation Clinica Habrush) Flat) and rubbed 20 times (30 seconds) in parallel with the plate at a load of 200 gf. Thereafter, the plate surface was washed with running water, the water on the plate surface was removed, and air-dried for about 1 hour.
The surface of the rinsed plate was observed with a microscope having a magnification of 100 times (manufactured by Keyence Corporation), and the remaining residue on the plate was evaluated. The evaluation criteria are as follows.
A: No residue remains on the plate.
○: Slight residue remains on the bottom (recess) of the image.
Δ: Waste remains on the plate image convex portion and the image bottom portion (concave portion).
X: Waste is adhered to the entire surface of the plate.
◎, ○, and △ were considered acceptable. Preferably, ◎ and ○.

(water resistant)
Evaluation of water resistance was made by cutting the prepared laser engraving relief printing plate precursor into 2 cm squares, dipping in 20 mL of distilled water controlled at 25 ° C. for 24 hr, drying at 100 ° C. for 2 hr, and the film before and after immersion The weight change was evaluated. A weight loss of 5% or less was judged to be a practically acceptable level.
◎: Weight reduction is 1% by mass or less ○: Weight reduction is more than 1% by mass and 3% by weight or less Δ: Weight reduction is more than 3% by mass and 5% by weight or less ×: Weight reduction is Over 5% by weight

  (Component A) It has been found that by removing the addition of an amino group-containing polymer and the rinsing step with an acidic liquid, the residue removal performance is remarkably improved. In particular, when both component B1 and component B2 coexist, the effect is great, and it becomes possible to provide a relief printing plate for laser engraving that is excellent in residue removal and water resistance.

Claims (13)

(Component A) a polymer containing an amino group, and
Have a relief forming layer comprising (Component B) a crosslinking agent,
The component A is a polymer having a side chain having an amino group, and the side chain having the amino group has a structure represented by the formula (A-1),
Relief printing plate precursor for laser engraving.

(In formula (A-1), * represents a position connected to the main chain of the polymer, R ¹ and R ² each independently represent a hydrogen atom, an alkyl group, or an aryl group, and R ³ represents a single atom. It represents a bond, or an alkylene group, a carbonyl group, an ester bond, an amide bond, or a linking group obtained by combining these, and any two or more of R ^{1 to} R ³ may be bonded to form a ring. )   In the formula (A-1), R ¹ And R ² The total number of carbon atoms is 0-12, and R ^Three Is a single bond or a combination of an alkylene group having an alkylene group having 1 to 3 carbon atoms, a carbonyl group, an ester bond, an amide bond, and an ester bond (—COO—) bonded to * via a carbonyl group. The relief printing plate precursor for laser engraving according to claim 1, wherein   The component B is at least one of (component B1) an ethylenically unsaturated compound and (component B2) a compound having a hydrolyzable silyl group and / or a silanol group. Relief printing plate precursor for laser engraving.   The relief printing plate precursor for laser engraving according to any one of claims 1 to 3, wherein the component B comprises (component B2) a compound having a hydrolyzable silyl group and / or a silanol group. The relief printing plate precursor for laser engraving according to any one of claims 1 to 4 , wherein the relief forming layer further comprises (Component C) a polymer not containing an amino group. The relief printing plate precursor for laser engraving according to any one of claims 1 to 5 , wherein the relief forming layer further comprises (Component C) a polymer not containing an amino group, and the Component C is a non-elastomer. The relief printing plate precursor for laser engraving according to any one of claims 1 to 6 , wherein the relief forming layer further comprises (Component D) a plasticizer.   The relief printing plate precursor for laser engraving according to any one of claims 1 to 7, wherein the component A is a resin selected from the group consisting of the following (1) to (4).
(1) A resin comprising a structural unit derived from a combination of a diol having a structure represented by the formula (A-1), a polyalkylene glycol, and an aromatic diisocyanate
(2) A resin comprising a structural unit derived from a combination of a diol having a structure represented by the formula (A-1), a polyalkylene glycol, an aromatic diisocyanate, and an aliphatic diisocyanate
(3) Diol having a structure represented by formula (A-1), ester compound of (meth) acrylic acid and triol compound having 3 to 10 carbon atoms, polyalkylene glycol, aromatic diisocyanate, and aliphatic diisocyanate Resin consisting of structural units derived from the combination of
(4) A resin comprising a structural unit derived from a combination of a diol having a structure represented by the formula (A-1), a polyalkylene glycol, an aliphatic dicarboxylic acid, and an aliphatic diamine A flexographic printing plate precursor for laser engraving Relief printing plate precursor as claimed in any one of claims 1 to 8. The relief printing plate precursor for laser engraving according to any one of claims 1 to 9 , wherein the relief forming layer is a crosslinked relief forming layer that has been thermally crosslinked and / or photocrosslinked. A crosslinking step of crosslinking the relief forming layer in the relief printing plate precursor for laser engraving according to any one of claims 1 to 10 by heat and / or light,
Engraving process for forming a relief layer by laser engraving a crosslinked relief forming layer, and
A method for making a relief printing plate, comprising a rinsing step of rinsing engraving residue remaining on the surface of the relief layer with an acidic liquid after the engraving step. The plate making method of the relief printing plate of Claim 11 whose pH of the said acidic liquid is 1.0-7.0. A relief printing plate obtained by the plate making method of a relief printing plate according to claim 11 or 12 .