JP2011194682A - Laser engraving relief printing plate original plate, relief printing plate making method, and relief printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser engraving relief printing plate original plate high in engraving sensitivity, a relief printing plate making method using the same, and a relief printing plate.SOLUTION: The laser engraving relief printing plate original plate includes, on a support, a relief forming layer containing at least one exothermic agent selected from the group composed of a hydrazide compound, a nitro compound, a nitroso compound, and a tetrazole compound (component A) and binder polymer where a glass transition temperature (Tg) is equal to or more than 20°C (compound B), and the content A of the component with respect to the total solid part of the relief forming layer is 1 to 20 mass%.

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.
Patent Document 1 discloses a printing plate material composed of a photosensitive layer containing nitrocellulose, a light absorber and a polyurethane elastomer, and a support on which the photosensitive layer is formed. Patent Document 2 is a printing in which a photosensitive layer for laser light and a light-transmitting surface layer are sequentially laminated on a support, and the photosensitive layer is composed of a binder made of nitrocellulose, a light absorber, and a polyurethane elastomer. Disclosed plate material. Patent Document 3 discloses a hydrophilic polymer (A1) containing hydroxyethylene as a structural unit, a hydrophilic polymer (A2) other than (A1), an ethylenically unsaturated monomer (B), a polymerization initiator (C), and a plasticizer ( A crosslinkable resin composition for laser engraving containing D) is disclosed.

Japanese Patent No. 3438404 Japanese Patent No. 3475591 JP 2006-2061 A

  An object of the present invention is to provide a relief printing plate precursor for laser engraving with high engraving sensitivity, a method for making a relief printing plate using the relief printing plate precursor for laser engraving, and a relief printing plate. That is.

The above problems have been solved by the following means.
<1> (Component A) at least one exothermic agent selected from the group consisting of a hydrazide compound, a nitro compound, a nitroso compound, and a tetrazole compound, and (Component B) a glass transition temperature (Tg) of 20 ° C. or higher. A relief for laser engraving comprising a relief forming layer containing a certain binder polymer on a support, and the content of the component A with respect to the total solid content of the relief forming layer is 1 to 20% by mass. Printing plate master,
<2> The relief printing plate precursor for laser engraving according to <1>, wherein the component B is an acrylic resin and / or polyvinyl acetal,
<3> The relief printing plate precursor for laser engraving according to <1> or <2>, wherein the relief forming layer further contains (Component C) a compound having a hydrolyzable silyl group and / or a silanol group,
<4> The relief printing plate precursor for laser engraving according to any one of <1> to <3>, wherein the relief forming layer further contains (Component D) a polymerizable compound,
<5> The relief printing plate precursor for laser engraving according to any one of <1> to <4>, wherein the relief forming layer further contains (Component E) a polymerization initiator,
<6> The relief printing plate precursor for laser engraving according to any one of <1> to <5>, wherein the relief forming layer further contains a (component F) photothermal conversion agent,
<7> The relief printing plate precursor for laser engraving according to any one of <1> to <6>, wherein the relief forming layer further contains a (component G) plasticizer,
<8> The relief printing plate precursor for laser engraving according to any one of <1> to <7>, wherein the relief forming layer further contains a (component H) fragrance,
<9> The relief printing plate precursor for laser engraving according to any one of <1> to <8>, which is a flexographic printing plate precursor,
<10> (1) <1> to <9> A crosslinking step of crosslinking the relief forming layer in the relief printing plate precursor for laser engraving according to any one by light and / or heat, and (2) crosslinking An engraving step of forming a relief layer by laser engraving the relief forming layer, and a method for making a relief printing plate,
<11> The method for making a relief printing plate according to <10>, wherein the crosslinking step is a step of crosslinking by heat,
<12> A relief printing plate produced by the plate making method of a relief printing plate according to <10> or <11>,
<13> The relief printing plate according to <12>, wherein the relief layer has a thickness of 0.05 mm to 10 mm.
<14> The relief printing plate according to <12> or <13>, wherein the Shore A hardness of the relief layer is from 50 ° to 90 °.

  According to the present invention, a relief printing plate precursor for laser engraving with high engraving sensitivity is provided, a relief printing plate making method using the relief printing plate precursor for laser engraving, and a relief printing plate are provided. did it.

  The relief printing plate precursor for laser engraving of the present invention comprises (Component A) at least one exothermic agent selected from the group consisting of a hydrazide compound, a nitro compound, a nitroso compound, and a tetrazole compound, and (Component B) a glass transition. The support has a relief forming layer containing a binder polymer having a temperature (Tg) of 20 ° C. or higher, and the content of the component A with respect to the total solid content of the relief forming layer is 1 to 20% by mass. It is characterized by that. In addition, in this specification, description of "X to Y" etc. which represent a numerical range is synonymous with "X or more and Y or less", and the both ends of a numerical range are included in the numerical range. Hereinafter, the present invention will be described in detail.

The relief printing plate precursor for laser engraving of the present invention can be widely applied to other uses. 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.
In this specification, regarding the explanation of the relief printing plate precursor for laser engraving, a predetermined amount of component A and component B are contained, and the surface as an image forming layer to be subjected to laser engraving is a flat layer, and The uncrosslinked layer is referred to as a “relief forming 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, each component will be described.

<(Component A) at least one exothermic agent selected from the group consisting of hydrazide compounds, nitro compounds, nitroso compounds, and tetrazole compounds>
The relief forming layer of the relief printing plate precursor for laser engraving of the present invention comprises at least one exothermic agent selected from the group consisting of (Component A) a hydrazide compound, a nitro compound, a nitroso compound, and a tetrazole compound. 1-20 mass% is contained with respect to the total solid content of the layer.

[Hydrazide compound]
The hydrazide compound is a general term for amides having a structure in which a hydrazine derivative and an oxo acid are condensed by dehydration.
Specific examples of the hydrazide compound include propionic acid hydrazide, salicylic acid hydrazide, hydroxynaphthoic acid hydrazide, carbohydrazide, thiocarbohydrazide, 1-naphthohydrazide, 2-chlorobenzhydrazide, 2-picolinic acid hydrazide, and m-anisic acid. Hydrazide, 4-aminobenzhydrazide, 2-thiophenecarboxylic acid hydrazide, 4-hydroxybenzohydrazide, 4-methoxybenzohydrazide, 4-nitrobenzohydrazide, nicotinic acid hydrazide, oxalyl dihydrazide, p-toluenesulfonyl hydrazide, phosphoric acid dihydrazide, Benzophenone hydrazide, 1,5-diphenylcarbonohydrazide, benzenesulfonyl hydrazide, 2,4,6-triisopropylbenzenesulfonyl hydrazide, 2- Citylenesulfonyl hydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, dodecanedioic acid dihydrazide, maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide diphthalide dihydradide 4,4′-oxybisbenzenesulfonyl hydrazide, trimesic acid trihydrazide, 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin, enocoic acid dihydrazide, 7,11-octadecadien-1,18-di Examples thereof include carbohydrazide, polyacrylic acid hydrazide, and acrylamide-acrylic acid hydrazide copolymer. Preferred hydrazide compounds include sulfonic acid derivatives, and arylsulfonyl hydrazide compounds are more preferred. Among them, benzenesulfonyl hydrazide, 2,4,6-triisopropylbenzenesulfonyl hydrazide, and 2-mesitylenesulfonyl hydrazide are more preferred. Further, the hydrazide value (equivalent of hydrazide group) is preferably 3.5 meq / g or more, more preferably 5.0 meq / g or more.

[Nitro compound]
The nitro compound is a general term for compounds having a nitro group —NO ₂ , and does not include a nitrate ester. Specifically, 2-methyl-2-nitropropane, nitromethane, nitroethane, nitropropane, 2-nitropropane, 1-nitrobutane, 2-nitrobutane, nitrobenzene, p-nitrobenzoic acid, m-nitrobenzoic acid, 3, 5-dinitrobenzoic acid, 3-chloro-2-nitrobenzoic acid, 3-nitrophthalic acid, 4-nitrophthalic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, o-nitrocinnamic acid, picric acid, o-nitrotoluene P-nitrotoluene, o-nitrophenol, p-nitrophenol, p-nitrophenyl acetate, p-nitrophenylacetic acid, 3-bromo-7-nitroindazole, 2-bromo-2-nitro-1,3-propanediol 2-bromo-4-nitroanisole, 1-chloro-2,4-dinitrobenzene N-chloromethyl-4-nitrophthalimide, 2-chloro-4-nitroaniline, 2-chloro-3-nitropyridine, 2,3-dichloronitrobenzene, 2,4-dinitroanisole, m-dinitrobenzene, 2,4 -Dinitrophenol, 2,4-dinitrophenylhydrazine, 3 ', 6'-bis (diethylamino) -2- (4-nitrophenyl) spiro [isoindole-1,9'-xanthen] -3-one, 2- Methyl-5-nitroaniline, 4-methyl-2-nitroaniline, metronidazole, o-nitroacetophenone, p-nitroacetophenone, o-nitroaniline, p-nitroaniline, o-nitrobenzaldehyde, m-nitrobenzaldehyde, 5- Nitrobenzotriazole, m-nitrobenzyl alcohol, p-ni B benzyl alcohol, 4- (p-nitrobenzyl) pyridine, and 4-nitro catechol. The nitro value (equivalent of nitro group) is preferably 2.0 meq / g or more, more preferably 5.0 meq / g or more.

[Nitroso compound]
The nitroso compound is a general term for compounds having a nitroso group —NO. Specifically, n-butyl-n-butanol nitrosamine, diisopropanol nitrosamine, 1-nitroso-2-naphthol, 2,4,6-tri-tert-butylnitrosobenzene, 2,4,6-triamino-5 Nitrosopyrimidine, 2,4-dinitrosolesorcinol, 2-nitroso-1-naphthol, 2-nitroso-5-dimethylaminophenol hydrochloride, 4- (dimethylamino) -4'-nitrosodiphenylamine, 4- (N- Butyl-N-nitrosoamino) butyric acid, 4-amino-2,6-dihydroxy-5-nitrosopyrimidine, 4-hydroxy-2-dimethylamino-5-nitroso-6-aminopyrimidine, 2-nitroso-1-naphthol- 4-sulfonic acid, 4-nitrosodiphenylamine, 4-nitrosophenol, 4-ni Trosolesorcinol-1-monomethyl ether, 5-nitroso-8-hydroxyquinoline, N, N′-dinitrosopentamethylenetetramine, N, N-dimethyl-4-nitrosoaniline, N, N-diethyl-4-nitroso Aniline, N-benzyl-N-nitroso-p-toluenesulfonamide, N-ethyl-N- (2-hydroxyethyl) nitrosamine, N-ethyl-N- (4-hydroxybutyl) nitrosamine, N-butyl-N- (4-hydroxybutyl) nitrosamine, N-methyl-N-nitroso-p-toluenesulfonamide, N-methyl-N-nitrosourethane, N-nitroso-N-methylaniline, N-nitrosodibutylamine, diethanolnitrosamine, N -Nitrosodiethylamine, N-nitrosodimethylamine, N-nitrosodiphenylamine, N-nitrosodipropylamine, N-nitrosoheptamethyleneimine, N-nitrosomorpholine, N-tert-butyl-N-ethylnitrosamine, nitrosobenzene and the like can be mentioned. The nitroso value (equivalent of nitroso group) is preferably 4.0 meq / g or more, more preferably 7.0 meq / g or more.

[Tetrazole compound]
Specific examples of the tetrazole compound include 1H-tetrazole, 1-methyltetrazole, 1-ethyltetrazole, 1-propyltetrazole, 1-butyltetrazole, 1-pentyltetrazole, 1-hexyltetrazole and 1-dodecyl. Tetrazole, 1-phenyltetrazole, 5-methyl-1H-tetrazole, 5-ethyl-1H-tetrazole, 5-propyl-1H-tetrazole, 5-butyl-1H-tetrazole, 5-pentyl-1H-tetrazole, 5-hexyl -1H-tetrazole, 5-dodecyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-benzyl-1H-tetrazole, 1-methyl-5-methyltetrazole, 1-ethyl-5-methyltetrazole, 1-propyl -5-methyl Tolazole, 1-butyl-5-methyltetrazole, 1-pentyl-5-methyltetrazole, 1-hexyl-5-methyltetrazole, 1-dodecyl-5-methyltetrazole, 1-phenyl-5-methyltetrazole, 1-naphthyl -5-methyltetrazole, 1-methyl-5-ethyltetrazole, 1-methyl-5-phenyltetrazole, 1-ethyl-5-phenyltetrazole, 1-propyl-5-phenyltetrazole, 1-butyl-5-phenyltetrazole 1-pentyl-5-phenyltetrazole, 1-hexyl-5-phenyltetrazole, 1-dodecyl-5-phenyltetrazole, 1-phenyl-5-phenyltetrazole, 5-amino-1H-tetrazole, 5- (2- Aminophenyl) -1H-tetrazo 1-methyl-5-aminotetrazole, 1-ethyl-5-aminotetrazole, 1-propyl-5-aminotetrazole, 1-butyl-5-aminotetrazole, 1-pentyl-5-aminotetrazole, 1-hexyl- 5-aminotetrazole, 1-dodecyl-5-aminotetrazole, 1-phenyl-5-aminotetrazole, 5-mercapto-1H-tetrazole, 1-methyl-5-mercaptotetrazole, 1-ethyl-5-mercaptotetrazole, 1 -Propyl-5-mercaptotetrazole, 1-butyl-5-mercaptotetrazole, 1-pentyl-5-mercaptotetrazole, 1-hexyl-5-mercaptotetrazole, 1-dodecyl-5-mercaptotetrazole, 1-cyclohexyl-5 Mercaptotetrazo 1-phenyl-5-mercaptotetrazole, 1-carboxymethyl-5-mercaptotetrazole, 1- (4-methoxyphenyl) -5-mercaptotetrazole, 1,5-pentamethylenetetrazole, 5- (methylthio)- 1H-tetrazole, 5- (ethylthio) -1H-tetrazole, 5- (benzylthio) -1H-tetrazole, 5,5-bitetrazole diammonium, 5,5-bitetrazole piperazine and the like can be mentioned. The tetrazole value (equivalent of tetrazole unit) is preferably 5.0 meq / g or more, more preferably 7.0 meq / g or more.

  Component A may be used alone or in combination of two or more. Content of the component A is 1-20 mass% with respect to the total mass of the total solid of a relief forming layer. If the content of component A is less than 1% by mass, the engraving sensitivity improvement effect may not be exhibited. On the other hand, when the content of component A exceeds 20% by mass, the relief shape may be deteriorated due to thermal decomposition of component A and generation of a large amount of gas. Moreover, when there is too much content of the component A, since the ratio of the compound related to bridge | crosslinking falls, the film | membrane physical property suitable for flexographic printing may not be implement | achieved. From the viewpoint of achieving both engraving sensitivity and film properties suitable for printing, the content of Component A is preferably 2 to 15% by mass, and more preferably 5 to 10% by mass.

<(Component B) Binder polymer having a glass transition temperature (Tg) of 20 ° C. or higher>
The relief forming layer of the relief printing plate precursor for laser engraving of the present invention contains (Component B) a binder polymer having a glass transition temperature (Tg) of 20 ° C. or higher. Engraving sensitivity can be increased by containing a binder polymer having a glass transition temperature (Tg) of 20 ° C. or higher.
As for the glass transition temperature (Tg), 10 mg of a sample is placed in a measurement pan of a scanning differential calorimeter (DSC, TA Instrument Q20000), and this is heated from 30 ° C. to 250 ° C. at 10 ° C./min in a nitrogen stream. after (1 ^st -run), the temperature was decreased at 10 ° C. / min to 0 ℃, warmed to 250 ° C. at 10 ° C. / min from further 0 ℃ Thereafter (2 ^nd -run), based in 2 ^nd -run The temperature is calculated by setting Tg as the temperature at which the line starts to be displaced from the low temperature side.

  An elastomer is generally defined scientifically as a polymer having a glass transition temperature of room temperature or lower (see Science Dictionary 2nd edition, edited by International Science Promotion Foundation, published by Maruzen Co., Ltd., P154). Therefore, component B refers to a polymer having a glass transition temperature exceeding normal temperature unlike such an elastomer. Although there is no restriction | limiting in the upper limit of the glass transition temperature of the component B, it is preferable from a viewpoint of handleability that it is 200 degrees C or less, and it is more preferable that it is 36 degreeC or more and 120 degrees C or less.

  Since component B takes a glass state at room temperature, thermal molecular motion is suppressed as compared with a rubber state. In laser engraving, in addition to the heat imparted by the infrared laser during laser irradiation, heat generated by the function of the component A and the photothermal conversion agent used together as desired (component F) is transferred to the binder polymer present in the surroundings. This is thermally decomposed and dissipated, resulting in engraving and forming a recess. In a preferred embodiment of the present invention, it is considered that heat transfer and thermal decomposition to component B occur effectively when (component F) a photothermal conversion agent is present in a state where thermal molecular motion of the non-elastomer is suppressed. It is estimated that the engraving sensitivity is further increased by such an effect.

  In the present invention, Component B is selected from the group consisting of (1) acrylic resin, (2) epoxy resin, (3) polyvinyl acetal, (4) polyester, and (5) polyurethane from the viewpoint of film strength. Preferably, the polymer is at least one polymer. Among these polymers, (Component C) those having a hydroxy group in the molecule are more preferable from the viewpoint of improving the reactivity of the compound having a hydrolyzable silyl group and / or silanol group. These polymers will be described.

(1) Acrylic resin Examples of the acrylic resin that can be used as Component B in the present invention include acrylic resins obtained using known acrylic monomers. Among them, an acrylic resin having a hydroxy group in the molecule is preferable.
Examples of the acrylic monomer used for the synthesis of the acrylic resin include (meth) acrylic acid esters, crotonic acid esters, and (meth) acrylamides. When synthesizing an acrylic resin having a hydroxy group, those having a hydroxy group in the molecule of the (meth) acrylic acid esters, crotonic acid esters, and (meth) acrylamides described above may be used. Specific examples of such an acrylic monomer having a hydroxy group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and the like.
Moreover, as an acrylic resin, you may synthesize | combine from acrylic monomers other than the acrylic monomer which has said hydroxyl group. Specifically, acrylic monomers other than the acrylic monomer having a hydroxy group include (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, Isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, acetoxyethyl (meth) acrylate , Phenyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (2-methoxyethoxy) ethyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) Acrylate, diethylene glycol monomethyl ether (meth) acrylate, diethylene glycol monoethyl ether (meth) acrylate, diethylene glycol monophenyl ether (meth) acrylate, triethylene glycol monomethyl ether (meth) acrylate, triethylene glycol monoethyl ether (meth) acrylate, di Propylene glycol monomethyl ether (meth) acrylate, polyethylene glycol monomethyl ether (meth) acrylate, polypropylene glycol monomethyl ether (meth) acrylate, monomethyl ether (meth) acrylate of a copolymer of ethylene glycol and propylene glycol, N, N-dimethyl Aminoethyl (meth) acrylate, N, N-die Aminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate. Furthermore, a modified acrylic resin comprising an acrylic monomer having a urethane group or a urea group can also be preferably used. Among these, alkyl (meth) acrylates such as lauryl (meth) acrylate and (meth) acrylates having an aliphatic cyclic structure such as t-butylcyclohexyl (meth) acrylate are particularly preferable from the viewpoint of water-based ink resistance. In addition, you may copolymerize said acrylic monomer with the acrylic monomer which has a hydroxyl group.
The weight average molecular weight of such an acrylic resin is preferably from 5,000 to 300,000, more preferably from 10,000 to 200,000, from the viewpoint of solubility in the coating solvent (time required for dissolution). 000-100,000 are more preferable.

(2) Epoxy resin It is also one of the preferable aspects to use an epoxy resin as the component B. Epoxy resins are preferred because they have hydroxy groups in the side chain. As a specific example, an epoxy resin obtained by polymerizing an adduct of bisphenol A and epichlorohydrin as a raw material monomer is preferable.
The epoxy resin preferably has a weight average molecular weight of 800 to 200,000 and a number average molecular weight of 800 to 60,000.

(3) Polyvinyl acetal In this specification, polyvinyl acetal and its derivative (s) are simply referred to as polyvinyl acetal. That is, in this specification, polyvinyl acetal is used in a concept including polyvinyl acetal and its derivatives, and is a general term for compounds obtained by cyclic acetalization of polyvinyl alcohol (obtained by saponifying polyvinyl acetate). Show.
The acetal content in the polyvinyl acetal (the total number of moles of the vinyl acetate monomer as the raw material is 100%, the mole% of vinyl alcohol units to be acetalized) is preferably 30 to 90 mol%, more preferably 50 to 85 mol%. 55 to 78 mol% is particularly preferable.
The vinyl alcohol unit in the polyvinyl acetal is preferably 10 to 70 mol%, more preferably 15 to 50 mol%, and particularly preferably 22 to 45 mol%, based on the total number of moles of the starting vinyl acetate monomer.
Moreover, the polyvinyl acetal may have a vinyl acetate unit as another component, and as its content, 0.01-20 mol% is preferable and 0.1-10 mol% is more preferable. The polyvinyl acetal may further have other copolymer units.
Examples of the polyvinyl acetal include a polyvinyl butyral derivative, a polyvinyl propylal derivative, a polyvinyl ethylal derivative, a polyvinyl methylal derivative, etc. Among them, a polyvinyl butyral derivative (hereinafter referred to as a PVB derivative) is preferable. In these descriptions, for example, the term “polyvinyl butyral derivative” is used in the present specification to include polyvinyl butyral and its derivatives, and the same applies to other polyvinyl acetal derivatives.
The molecular weight of the polyvinyl acetal is preferably 5,000 to 800,000, more preferably 8,000 to 500,000 as a weight average molecular weight from the viewpoint of maintaining a balance between engraving sensitivity and film property. Furthermore, from the viewpoint of improving the rinse performance of engraving residue, it is particularly preferably 50,000 to 300,000.

  Hereinafter, polyvinyl butyral will be described as a particularly preferable example of polyvinyl acetal, but is not limited thereto. The structure of the polyvinyl butyral derivative is as shown below, and includes these structural units.

  As the PVB derivative, it is also available as a commercial product, and preferred specific examples thereof include, from the viewpoint of alcohol solubility (particularly ethanol), “S-Lec B” series, “S-LEC K” (manufactured by Sekisui Chemical Co., Ltd.). KS) "series," Denkabutyral "manufactured by Denki Kagaku Kogyo Co., Ltd. is preferable. More preferably, from the viewpoint of alcohol solubility (especially ethanol), “S Lec B” series manufactured by Sekisui Chemical Co., Ltd. and “Denka Butyral” manufactured by Denki Kagaku Kogyo Co., Ltd. are preferred. Among these, particularly preferred commercial products are shown below together with the values of l, m and n and the molecular weight in the above formula. In the “S Lec B” series manufactured by Sekisui Chemical Co., Ltd., “BL-1” (l = 61, m = 3, n = 36 weight average molecular weight 19000), “BL-1H” (l = 67 , M = 3, n = 30 weight average molecular weight 2 million), “BL-2” (l = 61, m = 3, n = 36 weight average molecular weight about 27,000), “BL-5” ( l = 75, m = 4, n = 21 weight average molecular weight 32,000), “BL-S” (l = 74, m = 4, n = 22 weight average molecular weight 23,000), “BM-S (L = 73, m = 5, n = 22 weight average molecular weight 53,000), “BH-S” (l = 73, m = 5, n = 22 weight average molecular weight 66,000), In the “Denkabutyral” series manufactured by Denki Kagaku Kogyo Co., Ltd., “# 3000-1” (l = 71, m = 1, n = 28 weight average molecular weight. ), “# 3000-2” (l = 71, m = 1, n = 28 weight average molecular weight 9 million), “# 3000-4” (l = 71, m = 1, n = 28 weight average) Molecular weight 17,000), “# 4000-2” (l = 71, m = 1, n = 28 weight average molecular weight 152,000), “# 6000-C” (l = 64, m = 1, n = 35 weight average molecular weight 308,000), "# 6000-EP" (l = 56, m = 15, n = 29 weight average molecular weight 381,000), "# 6000-CS" (l = 74, m = 1, n = 25 weight average molecular weight 322,000) and “# 6000-AS” (l = 73, m = 1, n = 26 weight average molecular weight 242,000).

  In the case of using a resin composition using a PVB derivative, the relief forming layer is preferably formed by casting and drying a solution obtained by dissolving the PVB derivative in a solvent from the viewpoint of the smoothness of the film surface. .

(4) Polyester Polyester can be used as Component B in the present invention.
The polyester may be at least one polyester selected from the group consisting of a polyester comprising hydroxycarboxylic acid units and derivatives thereof, polycaprolactone (PCL) and derivatives thereof, poly (butylene succinic acid) and derivatives thereof. preferable.
In the present specification, “polyester composed of a hydroxycarboxylic acid unit” refers to a polyester obtained by a polymerization reaction using hydroxycarboxylic acid as one of raw materials. In the present specification, “hydroxycarboxylic acid” refers to a compound having at least one OH group and COOH group in the molecule. It is preferable that at least one OH group and COOH group of the “hydroxycarboxylic acid” are present in the vicinity, and the OH group and COOH group are preferably linked with 6 or less atoms, preferably 4 or less. More preferably.
Specific examples of the 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 are preferred.
The weight average molecular weight of the polyester is preferably from 5,000 to 300,000, more preferably from 10,000 to 200,000, more preferably from 20,000 to 100,000, from the viewpoint of solubility (time required for dissolution) in the coating solvent. 000 is more preferable.

(5) Polyurethane Polyurethane can also be used as Component B in the present invention. The polyurethane that can be used as component B in the present invention is a polyurethane having as a basic skeleton a structural unit that is a reaction product of at least one diisocyanate compound and at least one diol compound.
Specific examples of the diisocyanate compound include 2,4-tolylene diisocyanate, dimer of 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-xylylene diisocyanate, and m-xylylene diisocyanate. Aromatic diisocyanate compounds such as 4,4′-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3′-dimethylbiphenyl-4,4′-diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine Aliphatic diisocyanate compounds such as diisocyanate and dimer acid diisocyanate; isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), methylcyclohexane-2 , 4 (or 2,6) diisocyanate, 1,3- (isocyanatomethyl) cyclohexane, and other alicyclic diisocyanate compounds; And a diisocyanate compound which is a reaction product of diol and diisocyanate. Particularly, from the viewpoint of thermal decomposability, 4,4′-diphenylmethane diisocyanate and 1,5-naphthylene diisocyanate are preferable.
Specific examples of the diol compound include 1,4-dihydroxybenzene, 1,8-dihydroxynaphthalene, 4,4′-dihydroxybiphenyl, 2,2′-hydroxybinaphthyl, bisphenol A, 4,4′-. Examples include bis (hydroxyphenyl) methane, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol having a weight average molecular weight of 1,000 or less, and polypropylene glycol having a weight average molecular weight of 1,000 or less.
Preferable examples of the polyurethane include a polyurethane resin having a structure in which an aromatic group described in JP-A-2008-26653 is directly bonded to a urethane bond.
The molecular weight of the polyurethane as component B is preferably 10,000 or more in terms of weight average molecular weight, and more preferably in the range of 40,000 to 200,000. In particular, when a polyurethane having a molecular weight within this range is used, the strength of the resin crosslinked product formed by thermal crosslinking is excellent.

Among the polymers of (1) to (5), from the viewpoint of engraving sensitivity, at least one polymer selected from the group consisting of (1) acrylic resin, (2) epoxy resin, and (3) polyvinyl acetal. It is preferable that acrylic resin and / or polyvinyl acetal is more preferable, and polyvinyl acetal is more preferable.
Component B may be used alone or in combination of two or more.
15-75 mass% is preferable with respect to the solid content total mass of a relief forming layer, and, as for the total content of component B, 20-65 mass% is more preferable. When the content of Component B is 15% by mass or more, printing durability sufficient to use the obtained printing plate as a printing plate can be obtained, and when it is 75% by mass or less, other components are insufficient. Therefore, even when the printing plate is a flexographic printing plate, the flexibility sufficient for use as the printing plate can be obtained.

<(Component C) Compound having hydrolyzable silyl group and / or silanol group>
The relief forming layer of the relief printing plate precursor for laser engraving of the present invention contains (Component C) a compound having a hydrolyzable silyl group and / or a silanol group. The “hydrolyzable silyl group” is a silyl group having hydrolyzability, and 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. Can be mentioned. 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 following formula (1).

In the formula (1), at least one of R ^{1 to} R ³ is a water 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. It represents a decomposable 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). To express.
In the formula (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, a C1-C30 alkoxy group is preferable from a viewpoint of rinse property and printing durability. More preferably, it is a C1-C15 alkoxy group, More preferably, it is C1-C5, Most preferably, it is a C1-C3 alkoxy group, Most preferably, it is a methoxy group or an ethoxy group.
Examples of the halogen atom include F atom, Cl atom, Br atom, and I atom. From the viewpoint of ease of synthesis and stability, Cl atom and Br atom are preferable, and Cl atom is more preferable. is there.

Component C in the present invention is preferably a compound having one or more groups represented by the formula (1), more preferably a compound having two or more. In particular, a compound having two or more hydrolyzable silyl groups is preferably used. That is, a compound having two or more silicon atoms having a hydrolyzable group bonded in the molecule is preferably used. The number of silicon atoms bonded to the hydrolyzable group contained in Component C is preferably 2 or more and 6 or less, and most preferably 2 or 3.
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 (1) is preferably in the range of 2 or 3. 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.

Specific examples of preferable alkoxy groups include methoxy, ethoxy, propoxy, isopropoxy, butoxy, tert-butoxy, phenoxy, and benzyloxy. 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 C preferably has at least a sulfur atom, an ester bond, a urethane bond, an ether bond, a urea bond, or an imino group.
Among them, the component C preferably contains a sulfur atom from the viewpoint of crosslinkability, and from the viewpoint of engraving residue removal (rinse), an ester bond, urethane bond, or It preferably contains an ether bond (particularly an ether bond contained in an oxyalkylene group). Component C containing a sulfur atom improves the strength of the crosslinked relief forming layer and the relief layer.
Moreover, it is preferable that the component C in this invention is a compound which does not have an ethylenically unsaturated bond.

Component C in the present invention includes a compound in which a plurality of groups represented by the formula (1) are bonded via a divalent linking group, and such a divalent linking group is effective. From the viewpoint, a linking group having a sulfide group (—S—), an imino group (—N (R) —), or a urethane bond (—OCON (R) — or —N (R) COO—) is preferable. R represents a hydrogen atom or a substituent. Examples of the substituent in R include an alkyl group, an aryl group, an alkenyl group, an alkynyl group, and an aralkyl group.
There is no restriction | limiting in particular as the synthesis | combining method of component C, It can synthesize | combine by a well-known method. A typical synthesis method of component C containing a linking group having the above specific structure is shown below.

<Method for synthesizing a compound having a sulfide group as a linking group and having a hydrolyzable silyl group and / or silanol group>
The method for synthesizing Component C having a sulfide group as a linking group (hereinafter, appropriately referred to as “sulfide linking group-containing component C”) is not particularly limited. Specifically, for example, it has a halogenated hydrocarbon group. Reaction of component C and alkali sulfide, reaction of component C having mercapto group and halogenated hydrocarbon, reaction of component C having mercapto group and component C having halogenated hydrocarbon group, component C having halogenated hydrocarbon group Reaction of component C having an ethylenically unsaturated double bond with mercaptan, reaction of component C having an ethylenically unsaturated double bond and component C having a mercapto group, ethylenically unsaturated double bond Reaction of a compound having a bond with a component C having a mercapto group, reaction of a ketone with a component C having a mercapto group, a diazonium salt and a mercapto group Reaction of component C having a reaction, reaction of component C having a mercapto group and an oxirane, reaction of component C having a mercapto group and component C having an oxirane group, reaction of a component C having a mercaptan group and an oxirane group, mercapto Examples thereof include a synthesis method such as a reaction between component C having a group and aziridines.

<Method for synthesizing compound having imino group as linking group and having hydrolyzable silyl group and / or silanol group>
The synthesis method of component C having an imino group as a linking group (hereinafter, referred to as “imino linking group-containing component C” as appropriate) is not particularly limited. Specifically, for example, component C having an amino group and Reaction of halogenated hydrocarbon, reaction of component C having amino group and component C having halogenated hydrocarbon group, reaction of component C having halogenated hydrocarbon group and amines, component C having amino group and oxiranes Reaction of component C having an amino group and component C having an oxirane group, reaction of amines and component C having an oxirane group, reaction of component C having an amino group and aziridines, Reaction of component C having a heavy bond with amines, reaction of component C having an ethylenically unsaturated double bond and component C having an amino group, a compound having an ethylenically unsaturated double bond, and Reaction of component C having mino group, reaction of compound having acetylenic unsaturated triple bond and component C having amino group, reaction of component C having imine unsaturated double bond and organic alkali metal compound, imine Examples of the synthesis method include a reaction between Component C having a saturated double bond and an organic alkaline earth metal compound, and a reaction between Component C having a carbonyl compound and an amino group.

<Method for synthesizing compound having urethane bond (ureylene group) as linking group and having hydrolyzable silyl group and / or silanol group>
The method for synthesizing Component C having a ureylene group as a linking group (hereinafter referred to as “ureylene linking group-containing component C” as appropriate) is not particularly limited. Examples include synthetic methods such as reaction of isocyanates, reaction of component C having an amino group and component C having isocyanate, and reaction of component C having amines and isocyanate.

  Component C is preferably a compound represented by the following formula (C-1) or formula (C-2).

（式（Ｃ−１）及び式（Ｃ−２）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 (C-1) and Formula (C-2), 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 ³ in Formula (C-1) and formula (C-2), it has the same meaning as R ¹ to R ³ in Formula (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 is
From the viewpoint of engraving residue removal (rinseability), it preferably has an ether bond, and more preferably has an ether bond contained in an oxyalkylene group.
Among the compounds represented by formula (C-1) or formula (C-2), from the viewpoint of crosslinkability and the like, in formula (C-1), n ¹ -valent linking group and / or L ² The divalent linking group is preferably a group having a sulfur atom.

  Specific examples of component C applicable to the present invention are shown below. For example, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxy Silane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, p-styryltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacrylic Roxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxy Silane, N- (β-aminoethyl) -γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercapto Propyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, dimethoxy-3-mercaptopropylmethylsilane, 2- (2-aminoethylthioethyl) diethoxymethylsilane, 3- (2-acetoxyethyl) Thiopropyl) dimethoxymethylsilane, 2- (2-aminoethylthioethyl) triethoxysilane, dimethoxymethyl-3- (3-phenoxypropylthiopropyl) silane, bis (triethoxysilylpropyl) disulfide, bis (tri Toxisilylpropyl) 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-chloropropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, trimethylsilanol, Examples thereof include 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 C can be obtained by appropriately synthesizing, but it is preferable from the viewpoint of cost to use a commercially available product. Examples of component C include 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 the product corresponds to this, these commercially available products may be appropriately selected and used according to the purpose in the relief forming layer of the relief printing plate precursor for laser engraving of the present invention.

As component C 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 C in the resin composition of the present invention may be used alone or in combination of two or more.
Content of the component C contained in the relief forming layer of the relief printing plate precursor for laser engraving of the present invention is in the range of 0.1 to 80% by mass in terms of solid content with respect to the total mass of the relief forming layer. Preferably, it is in the range of 1 to 40% by mass, and most preferably in the range of 5 to 30% by mass.

<(Component D) polymerizable compound>
In the present invention, from the viewpoint of forming a crosslinked structure in the relief forming layer, in order to form this, the relief forming layer of the relief printing plate precursor for laser engraving of the present invention preferably contains a polymerizable compound. .
The polymerizable compound that can be used here can be arbitrarily selected from compounds having at least one ethylenically unsaturated bond, preferably two or more, more preferably 2 to 6, and even more preferably two. .
Further, the polymerizable compound is a compound different from Component B, and is preferably a compound having an ethylenically unsaturated bond at the end of the molecule. Further, the molecular weight (weight average molecular weight) of the polymerizable compound is preferably less than 5,000.
There is no restriction | limiting in particular as said polymeric compound, Although a well-known thing can be used, The thing as described in Paragraph 0098-0124 of Unexamined-Japanese-Patent No. 2009-204962 and Unexamined-Japanese-Patent No. 2009-255510 is illustrated. it can.
Since it is necessary to form a crosslinked structure in the relief forming layer of the relief printing plate precursor for laser engraving of the present invention, a polyfunctional monomer is preferably used. The molecular weight of these polyfunctional monomers is preferably 120 to 3,000, and more preferably 200 to 2,000.

  Examples of monofunctional monomers and polyfunctional monomers include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.) and esters of polyhydric alcohol compounds, unsaturated carboxylic acids, Examples include amides with polyvalent amine compounds.

  Preferred components D include glycerol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) ) Acrylate, ethoxylated pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethoxylated dipentaerythritol hexa (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, ethoxylated bisphenol A di ( (Meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, propoxylated bisphenol A di (meth) a Relate, polytetramethylene glycol di (meth) acrylate, ethoxylated isocyanuric acid tri (meth) acrylate, glycerin tri (meth) acrylate, etc. ethoxylated glycerin tri (meth) acrylate.

By using a polymerizable compound in the relief forming layer of the relief printing plate precursor for laser engraving of the present invention, film physical properties such as brittleness and flexibility in the crosslinked relief forming layer can be adjusted.
Further, the content of the (Component D) polymerizable compound in the relief forming layer of the relief printing plate precursor for laser engraving of the present invention is the total of the relief forming layer in terms of solid content from the viewpoint of flexibility and brittleness of the crosslinked film. 5-60 mass% is preferable with respect to the mass, and the range of 8-30 mass% is 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, and is preferably used in combination with (Component D) a polymerizable compound.
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. Among these, organic peroxides or azo compounds are more preferable, and organic peroxides are particularly preferable from the viewpoint of engraving sensitivity and a favorable relief edge shape when applied to the relief forming layer of the relief printing plate precursor.

Further, as a preferred combination component, it is more preferable to use an organic peroxide and a photothermal conversion agent in combination, since the engraving sensitivity is extremely high, and the organic peroxide and the photothermal conversion agent carbon black are used in combination. The embodiment was most preferred.
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 because it is generated synergistically.

In the present invention, the (component E) polymerization initiator may be used alone or in combination of two or more.
The content of the (component E) polymerization initiator in the relief forming layer of the relief printing plate precursor for laser engraving of the present invention is preferably 0.01 to 10% by mass relative to the total solid content of the relief forming layer. 1-3 mass% is more preferable. By making the content of the polymerization initiator 0.01% by mass or more, the effect of adding this is obtained, and the crosslinkable relief forming layer is rapidly crosslinked. In addition, when the content is 10% by mass or less, other components are not insufficient, and printing durability sufficient for use as a relief printing plate can be obtained.

<(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 (Component F) a photothermal conversion agent. That is, it is considered that the photothermal conversion agent in the present invention promotes thermal decomposition of a 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 in the present invention.

  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, carbon black can be used regardless of the classification according to ASTM or the use (for example, for color, for rubber, for dry battery, etc.). 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 of the relief printing plate precursor for laser engraving of the present invention varies greatly depending on the molecular extinction coefficient inherent to the molecule, but it is 0. 0% of the total solid mass of the relief forming layer. The range of 01-30 mass% is preferable, 0.05-20 mass% is more preferable, and 0.1-10 mass% is especially preferable.

<(Component G) Plasticizer>
The plasticizer has an effect of softening the relief layer and preferably has good compatibility with the component B.
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, phthalic acid derivatives, citric acid derivatives, and glycol derivatives are preferable.
Examples of adipic acid derivatives include bis (2-ethylhexyl) adipate, bis (isononyl) adipate, bis (isodecyl) adipate, and bis (2-butoxyethyl) adipate. Examples of phthalic acid derivatives include dioctyl Phthalate, didodecyl phthalate, etc., citric acid derivatives, tributyl citrate, etc., glycol derivatives, polyethylene glycols, polypropylene glycol (monool type and diol type), polypropylene glycol (monool type and diol type) Etc. are preferably used.
Component G may use only 1 type and may use 2 or more types together. The content of component G is preferably 1 to 50% by mass, more preferably 10 to 40% by mass, and still more preferably 20 to 30% by mass based on the total mass of the relief forming layer in terms of solid content.

<(Component H) Fragrance>
In order to reduce odor, the relief forming layer of the relief printing plate precursor for laser engraving of the present invention preferably contains (Component H) a fragrance. The fragrance is effective for reducing odor during the production of the relief printing plate precursor and during laser engraving.
By containing a fragrance | flavor, when drying the liquid resin composition containing each component apply | coated during manufacture, the solvent odor which volatilizes can be masked. Also, it is possible to mask unpleasant odors such as amine odor, ketone odor, aldehyde odor, and burnt odor of the resin generated during laser engraving. Moreover, since a fragrance | flavor is effective also in reducing the smell of sulfur, when a compound which has a sulfur atom is included, it is useful.

As a fragrance | flavor, a well-known fragrance | flavor can be selected suitably and can be used, a fragrance | flavor can also be used individually by 1 type and can also be used combining a some fragrance | flavor.
The fragrance is preferably appropriately selected depending on the components used, and is preferably optimized by combining known fragrances. Perfumes include "synthetic fragrances-chemistry and product knowledge" (Motoichi Into, published by Chemical Industry Daily Inc.), "Introduction to Fragrance Chemistry" (written by Shoji Watanabe, published by Baifukan Co., Ltd.), The fragrances described in “Encyclopedia” (edited by the Japan Fragrance Association, published by Asakura Shoten Co., Ltd.) and “Applied Fragrance Chemicals II, Isolated Fragrances, Synthetic Fragrances, and Fragrances” (published by Yodogawa Shoten Co., Ltd.). Moreover, as a fragrance | flavor which can be used for this invention, the fragrance | flavor described in Paragraph 0012-0025 of Unexamined-Japanese-Patent No. 2009-203310 can be illustrated.

  Among them, as perfumes, terpene compounds such as terpene hydrocarbons, terpene alcohols, terpene oxides, terpene aldehydes, terpene ketones, terpene carboxylic acids, terpene lactones, terpene carboxylic esters, and / or aliphatic It is preferable to use ester compounds such as esters, furan carboxylic acid esters, aliphatic cyclic carboxylic acid esters, cyclohexyl carboxylic acid esters, and aromatic carboxylic acid esters.

Moreover, it is preferable to use a heat-resistant fragrance | flavor as a fragrance | flavor in this invention. By using heat-resistant fragrance, masking bad odor caused by decomposition of resin by releasing fragrance at the time of laser engraving, and also (crosslinking) relief forming layer which can be stored for a long time without emitting fragrance at room temperature It can be a relief layer.
Here, the heat-resistant fragrance is a fragrance that masks the bad odor caused by decomposition of the resin by releasing the fragrance during the laser engraving work, and that can be stored for a long time with almost no fragrance emitted at room temperature. Say.

As the heat-resistant fragrance, specifically, one or more fragrance ingredients selected from the group consisting of heliotrop, jasmine, rose, orange flower, amber, and musk are shown below. Preferably used.
Further, as a more specific fragrance, an oriental base mainly composed of the following patchouli oil, a fragrance component selected from the group consisting of the following rose, amber, musk, and jasmine types, a solvent dioctyl phthalate There is a tabu (TABU) type fragrance on top of (DOP).
Oriental bases include patchouli oil, hercoline (methyl abieticate), vanillin, ethyl vanillin, coumarin, and the like. Rose-based fragrance ingredients include phenylethyl alcohol, geraniol, iso-bornylmethoxycyclohexanol (iso -Bornyl methoxycyclohexanol) and the like, examples of the amber-based fragrance component include tetrahydroparamethylquinoline and the like, examples of the musk-based fragrance component include galac solid and musk ketone, and examples of the jasmine-based fragrance component include α -Amylcinnamaldehyde, methyl dihydrojasmonate and the like.

In addition, the following heliotrope-based fragrance components are used as the main fragrance, and jasmine-based fragrance components, as well as rose-based fragrance components and orange flower-based fragrance components are added to the solvent DOP in order to impart harmonicity and diffusibility. Amethyst type fragrances added together with are also preferred.
Examples of the heliotrope-based fragrance component include heliotropin, musk ketone, coumarin, ethyl vanillin, acetyl cedrene, hercoline (methyl abieticate), eugenol, methyl ionone, and the like. , Iso-bornyl methoxycyclohexanol and the like, orange flower fragrance components include methyl anthranilate, γ-undecalactone, γ-nona lactone and the like, and jasmine fragrance components include methyl dihydrojas. Examples include monates.
Furthermore, it is also preferable to use 6-hydroxyalkanoic acid or 6- (5- and / or 6-alkenoyloxy) alkanoic acid as another heat-resistant fragrance.

The fragrance preferably includes at least a vanillin fragrance, a jasmine fragrance, or a mint fragrance, more preferably includes a vanillin fragrance and / or a mint fragrance, and further includes a vanillin fragrance. preferable.
Specific examples of vanillin-based fragrances include vanillin, vanillic acid, vanillyl alcohol, vanillin propylene glycol acetal, methyl vanillin, ethyl vanillin, parahydroxybenzoic acid, parahydroxybenzaldehyde and the like.
Specific examples of the jasmine perfume include methyl dihydrojasmonate, methyl epi-dihydro jasmonate, methyl jasmonate, methyl epi-jasmonate, cis jasmon, jasmonan, cis jasmon lactone, dihydro jasmon lactone, jasmine lactone, γ- Jasmolactone, cis jasmon lactone, methyl γ-decalactone, jasmolactone, γ-hexalactone, γ-octalactone, γ-nonalactone, 4-methyl-5-hexenolide-1: 4, 2-n-hexylcyclopenta Preferred examples include non-alkyl-cycloheptylmethyl carbonate and the like.
Specifically, menthol, menthol, cineole, 1-menthol, d-menthol, dl-menthol, d-neomenthol, d-isomenthol, d-neomenthol, peppermint oil, spearmint oil, peppermint oil Etc. can be preferably exemplified.

  0.003-1.5 mass% is preferable with respect to the total solid content of a relief forming layer, and, as for content of a fragrance | flavor, 0.005-1.0 mass% is more preferable. When it is in the above range, the masking effect can be sufficiently exhibited, the fragrance of the fragrance is moderate, and the working environment is improved.

<Other additives>
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 fillers, waxes, process oils, organic acids, metal oxides, antiozonants, antiaging agents, thermal polymerization inhibitors, colorants, and the like, and these may be used alone. 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 per 100 parts 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 metal oxide added to form such a metal salt in the system is preferably 0.1 to 10 parts, more preferably 2 to 10 parts per 100 parts of component B.
The amount of the organic acid added is preferably 0.1 to 5 parts, more preferably 0.1 to 3 parts per 100 parts of component B.

  An alcohol exchange reaction catalyst is preferably added to the relief forming layer in order to promote the formation of a crosslinked structure of component C. 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. As the alcohol exchange reaction catalyst, an acid or a basic compound is used as it is, or a catalyst in which it is dissolved in a solvent such as water or an organic solvent (hereinafter also referred to as an acidic catalyst and 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 basic catalysts include ammoniacal bases such as ammonia water, amines, alkali metal hydroxides, alkali metal alkoxides, alkaline earth oxides, quaternary ammonium salt compounds, quaternary phosphonium salt compounds, and the like. Amines are preferred.
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-element amines having hetero atoms such as S and Se; and (c) containing a condensed ring. Cyclic amines are preferred.
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.

  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)
In the present invention, the “relief printing plate precursor for laser engraving” means a state in which a relief forming layer having a crosslinkability made of a resin composition for laser engraving has been cured and is cured by light or heat. Both or either one.
In the present invention, the “relief-forming layer” refers to a layer in a state before being crosslinked, and may be dried as necessary.
In the present invention, the “crosslinked relief forming layer” refers to a layer obtained by crosslinking the relief forming layer. The cross-linking is performed by heat and / or light. The crosslinking is not particularly limited as long as the resin composition containing each component is cured.
A “relief printing plate” is produced by laser engraving a relief printing plate precursor for laser engraving having a crosslinked relief forming layer. In the present invention, the “relief layer” refers to a layer engraved by 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 further has, if necessary, an adhesive layer between the support and the (crosslinked) relief forming layer, and a slip coat layer and a protective film on the (crosslinked) relief forming layer. May be.

<Relief forming layer>
The relief forming layer is a layer made of a resin composition containing the above components, and is a heat-crosslinkable and / or photocrosslinkable layer. As the relief printing plate precursor for laser engraving of the present invention, in addition to the crosslinked structure of component B and component C, it further contains (Component D) a polymerizable compound and (Component E) a polymerization initiator, thereby further crosslinking. What has the relief forming layer which provided the function of property is preferable.

The relief printing plate using the relief printing plate precursor for laser engraving includes a relief printing plate precursor having a crosslinked relief forming layer by crosslinking the relief forming layer, and then forming a crosslinked relief forming layer (hard relief forming layer). It is preferable that the relief printing plate is produced by forming a relief layer by laser engraving. 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 having the above components for the relief forming layer into a sheet shape or a sleeve shape. The relief forming layer is provided on a support described later. 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. Examples of materials (adhesives) that can be used for the adhesive layer include: 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, but the method for producing the relief printing plate precursor for laser engraving is a layer formation for forming a relief forming layer comprising the resin composition. Preferably, the production method includes a step and a crosslinking step in which the relief forming layer is thermally crosslinked and / or photocrosslinked to obtain a relief printing plate precursor having a crosslinked relief forming layer.

  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>
In this invention, it is preferable that the plate-making method of the relief printing plate for laser engraving includes the layer formation process which forms the relief forming layer which consists of the said resin composition.
As a method for forming the relief forming layer, a resin composition is prepared, and after removing the solvent as necessary, a method of melt extrusion on a support, a resin composition is prepared, and the resin composition is placed on the support. And a method of removing the solvent by drying in an oven.
The resin composition can be produced, for example, by dissolving component A, component B and other optional components in a suitable solvent. Since most of the solvent components need to be removed at the stage of producing the relief printing plate precursor, low-molecular alcohols that easily volatilize (for example, methanol, ethanol, n-propanol, isopropanol, propylene glycol monomethyl) are used as the solvent. It is preferable to keep the total amount of solvent added 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 mm or more and 10 mm or less, more preferably 0.05 mm or more and 7 mm or less, and more preferably 0.05 mm or more and 3 mm or less before and after crosslinking. Further preferred.

<Crosslinking process>
The plate making method of the relief printing plate for laser engraving of the present invention is preferably a production method including a crosslinking step of crosslinking the relief forming layer in the relief printing plate precursor for laser engraving with heat and / or light.
The relief forming layer can be crosslinked by heating and / or irradiating the relief printing plate precursor for laser engraving. 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. In the case of crosslinking by light, a step of irradiating actinic rays with an actinic ray source is required. This step may be performed either before or after removing the solvent. Examples of the active light source include a high-pressure mercury lamp, an ultra-high pressure mercury lamp, an ultraviolet fluorescent lamp, a carbon arc lamp, a xenon lamp, and a sterilization basket.
By crosslinking the relief forming layer, there is an advantage that the relief formed first after laser engraving becomes sharp, and second, the adhesiveness of engraving residue generated during laser engraving is suppressed.

(Relief printing plate and plate making method)
The plate making method of the relief printing plate of the present invention comprises (1) a crosslinking step of crosslinking the relief forming layer in the relief printing plate precursor for laser engraving of the present invention with heat and / or light, and (2) a crosslinked relief. An engraving step of forming a relief layer by laser engraving the forming layer.
The relief printing plate of the present invention is a relief printing plate made by the plate making method of the relief printing plate of the present invention. The relief printing plate of the present invention can be suitably used when printing water-based ink. The crosslinking step in the plate making method of the relief printing plate of the present invention is synonymous with the crosslinking step in the method for producing a relief printing plate precursor for laser engraving, and the preferred range is also the same.

<Engraving process>
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, a 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 a portion of a groove that prints fine punched characters is engraved deeply As a result, the ink is less likely to be buried in the groove, and it is possible to suppress the crushing of the extracted characters.
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 can be downsized with high efficiency and low cost in laser oscillation compared to a CO ₂ laser. Moreover, since it is small, it is easy to form an array. In addition, the beam shape can be controlled by fiber processing.
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.

Moreover, since the semiconductor laser with a fiber can output a laser beam efficiently by attaching an optical fiber, it is effective for the engraving process in the present invention. In addition, the beam shape can be controlled by fiber processing. For example, the beam profile can have a top hat shape, and energy can be stably given to the plate surface. Details of semiconductor lasers are described in “Laser Handbook 2nd Edition” edited by Laser Society, Practical Laser Technology and Electronic Communication Society.
Also, a plate making apparatus equipped with a fiber-coupled semiconductor laser that can be suitably used for a plate making method of 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.

In the plate making method of the relief printing plate of the present invention, after the engraving step, a rinsing step of rinsing the engraved surface with water or a liquid containing water as a main component is engraved after the engraving step, if necessary. A drying step for drying the relief layer, and a post-crosslinking step for imparting energy to the relief layer after engraving and further crosslinking the relief layer may be included.
As a means for rinsing, engraving with a method of washing with water or a liquid containing water as a main component, a method of spraying high-pressure water, a known batch type or conveying type brush type washing machine as a photosensitive resin letterpress developing machine A method of brushing the surface mainly in the presence of water can be mentioned. If the engraving residue cannot be removed, a rinsing liquid to which soap or a surfactant is added may be used.
When the rinsing process for rinsing the engraving surface is performed, it is preferable to add a drying process for drying the engraved relief forming layer and volatilizing 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.

Since handling is easy, 9-14 are preferable, as for pH of a rinse liquid, 10-13 are more preferable, and 11-12.5 are further more preferable. 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.
The rinse liquid preferably contains water as a main component. Moreover, the rinse liquid may contain water miscible solvents, such as alcohol, acetone, tetrahydrofuran, etc. as solvents other than water.

  It is preferable that the rinse liquid contains a surfactant. As surfactants, betaine such as carboxybetaine compounds, sulfobetaine compounds, phosphobetaine compounds, amine oxide compounds, or phosphine oxide compounds from the viewpoint of reducing engraving residue removal and influence on the relief printing plate. Preferred examples include compounds (amphoteric surfactants). The betaine compound is preferably a compound represented by the formula (1) and / or a compound represented by the formula (2).

（式（１）中、Ｒ¹〜Ｒ³はそれぞれ独立に、一価の有機基を表し、Ｒ⁴は単結合、又は、二価の連結基を表し、ＡはＰＯ（ＯＲ⁵）Ｏ^-、ＯＰＯ（ＯＲ⁵）Ｏ^-、Ｏ^-、ＣＯＯ^-、又は、ＳＯ₃ ^-を表し、Ｒ⁵は、水素原子、又は、一価の有機基を表し、Ｒ¹〜Ｒ³のうち２つ以上の基が互いに結合し環を形成してもよい。）

(In formula (1), R ^{1 to} R ³ each independently represents a monovalent organic group, R ⁴ represents a single bond or a divalent linking group, and A represents PO (OR ⁵ ) O ^−. , OPO (OR ⁵ ) O ⁻ , O ⁻ , COO ⁻ , or SO ₃ ⁻ , R ⁵ represents a hydrogen atom or a monovalent organic group, and two or more of R ^{1 to} R ³ May be bonded to each other to form a ring.)

（式（２）中、Ｒ⁶〜Ｒ⁸はそれぞれ独立に、一価の有機基を表し、Ｒ⁹は単結合、又は、二価の連結基を表し、ＢはＰＯ（ＯＲ¹⁰）Ｏ^-、ＯＰＯ（ＯＲ¹⁰）Ｏ^-、Ｏ^-、ＣＯＯ^-、又は、ＳＯ₃ ^-を表し、Ｒ¹⁰は、水素原子、又は、一価の有機基を表し、Ｒ⁶〜Ｒ⁸のうち２つ以上の基が互いに結合し環を形成してもよい。）

(In formula (2), R ^{6 to} R ⁸ each independently represents a monovalent organic group, R ⁹ represents a single bond or a divalent linking group, and B represents PO (OR ¹⁰ ) O ^−. , OPO (OR ¹⁰ ) O ⁻ , O ⁻ , COO ⁻ , or SO ₃ ⁻ , R ¹⁰ represents a hydrogen atom or a monovalent organic group, and two or more of R ^{6 to} R ⁸ May be bonded to each other to form a ring.)

The compound represented by the formula (1) or the compound represented by the formula (2) is preferably a carboxybetaine compound, a sulfobetaine compound, a phosphobetaine compound, an amine oxide compound, or a phosphine oxide compound. In the present invention, N = O amine oxide compound, and, each structure of the P = O phosphine oxide ^{compounds, N + -O -, P +} -O - shall be regarded as.
R ^{1 to} R ³ in the formula (1) each independently represent a monovalent organic group. Moreover, although two or more groups among R ^{1 to} R ³ may be bonded to each other to form a ring, it is preferable that no ring is formed.
The monovalent organic group in R ^{1 to} R ³ is not particularly limited, but an alkyl group, an alkyl group having a hydroxy group, an alkyl group having an amide bond in the alkyl chain, or an ether bond in the alkyl chain. The alkyl group is preferably an alkyl group, an alkyl group having a hydroxy group, or an alkyl group having an amide bond in the alkyl chain.
In addition, the alkyl group in the monovalent organic group may be linear, branched or have a ring structure.
Further, it is particularly preferable that two of R ^{1 to} R ³ are methyl groups, that is, the compound represented by the formula (1) has an N, N-dimethyl structure. With the above structure, particularly good rinsing properties are exhibited.

R ⁴ in the formula (1) represents a single bond or a divalent linking group, and is a single bond when the compound represented by the formula (1) is an amine oxide compound.
The divalent linking group in R ⁴ is not particularly limited, but is preferably an alkylene group or an alkylene group having a hydroxy group, and is an alkylene group having 1 to 8 carbon atoms or a carbon having a hydroxy group. It is more preferably an alkylene group having 1 to 8 carbon atoms, and further preferably an alkylene group having 1 to 3 carbon atoms or an alkylene group having 1 to 3 carbon atoms having a hydroxy group.
A in the formula (1) represents PO (OR ⁵ ) O ⁻ , OPO (OR ⁵ ) O ⁻ , O ⁻ , COO ⁻ , or SO ₃ ^−, and represents O ⁻ , COO ⁻ , or SO ₃ ^−. is preferably, COO ^- is more preferable.
When A ⁻ is O ⁻ , R ⁴ is preferably a single bond.
R ⁵ in PO (OR ⁵ ) O ⁻ and OPO (OR ⁵ ) O ⁻ represents a hydrogen atom or a monovalent organic group, and is a hydrogen atom or an alkyl group having one or more unsaturated fatty acid ester structures. It is preferable that
R ⁴ is preferably a group having no PO (OR ⁵ ) O ⁻ , OPO (OR ⁵ ) O ⁻ , O ⁻ , COO ⁻ , and SO ₃ ⁻ .

R ^{6 to} R ⁸ in the formula (2) each independently represent a monovalent organic group. Moreover, although two or more groups among R ^{6 to} R ⁸ may be bonded to each other to form a ring, it is preferable that no ring is formed.
The monovalent organic group in R ^{6 to} R ⁸ is not particularly limited, but is preferably an alkyl group, an alkenyl group, an aryl group, or a hydroxy group, and is preferably an alkenyl group, an aryl group, or a hydroxy group. More preferably.
In addition, the alkyl group in the monovalent organic group may be linear, branched or have a ring structure.
Moreover, it is particularly preferable that two of R ^{6 to} R ⁸ are aryl groups.

R ⁹ in the formula (2) represents a single bond or a divalent linking group, and is a single bond when the compound represented by the formula (2) is a phosphine oxide compound.
The divalent linking group for R ⁹ is not particularly limited, but is preferably an alkylene group or an alkylene group having a hydroxy group, and is an alkylene group having 1 to 8 carbon atoms or a carbon having a hydroxy group. It is more preferably an alkylene group having 1 to 8 carbon atoms, and further preferably an alkylene group having 1 to 3 carbon atoms or an alkylene group having 1 to 3 carbon atoms having a hydroxy group.
B in the formula (2) represents PO (OR ¹⁰ ) O ⁻ , OPO (OR ¹⁰ ) O ⁻ , O ⁻ , COO ⁻ , or SO ₃ ^−, and is preferably O ⁻ .
When B ⁻ is O ⁻ , R ⁹ is preferably a single bond.
R ¹⁰ in PO (OR ¹⁰ ) O 2 ^— and OPO (OR ¹⁰ ) O 2 ^— represents a hydrogen atom or a monovalent organic group, and represents a hydrogen atom or an alkyl group having one or more unsaturated fatty acid ester structures. It is preferable that
R ⁹ is preferably a group having no PO (OR ¹⁰ ) O ⁻ , OPO (OR ¹⁰ ) O ⁻ , O ⁻ , COO ⁻ , and SO ₃ ⁻ .

  The compound represented by the formula (1) is preferably a compound represented by the following formula (3).

（式（３）中、Ｒ¹は一価の有機基を表し、Ｒ⁴は単結合、又は、二価の連結基を表し、ＡはＰＯ（ＯＲ⁵）Ｏ^-、ＯＰＯ（ＯＲ⁵）Ｏ^-、Ｏ^-、ＣＯＯ^-、又は、ＳＯ₃ ^-を表し、Ｒ⁵は、水素原子、又は、一価の有機基を表す。）

(In the formula (3), R ¹ represents a monovalent organic group, R ⁴ represents a single bond or a divalent linking group, and A represents PO (OR ⁵ ) O ⁻ , OPO (OR ⁵ ) O. ^-, O -, COO ^-, or SO ₃ ^- represents, R ⁵ represents a hydrogen atom, or a monovalent organic group).

Equation (3) R ¹ in, A, R ⁴ and, R ⁵ is, R ^1, A, R ⁴ in the formula (1), and has the same meaning as R ^5, a preferred range is also the same.
The compound represented by the formula (2) is preferably a compound represented by the following formula (4).

（式（４）中、Ｒ⁶〜Ｒ⁸はそれぞれ独立に、アルキル基、アルケニル基、アリール基、又は、ヒドロキシ基を表す。ただし、Ｒ⁶〜Ｒ⁸の全てが同じ基となることはない。）

(In formula (4), R ^{6 to} R ⁸ each independently represents an alkyl group, an alkenyl group, an aryl group, or a hydroxy group. However, not all of R ^{6 to} R ⁸ are the same group. .)

R ^{6 to} R ⁸ in the formula (4) each independently represents an alkyl group, an alkenyl group, an aryl group, or a hydroxy group, and preferably an alkenyl group, an aryl group, or a hydroxy group.
Specific examples of the compound represented by the formula (1) or the compound represented by the formula (2) include the following compounds.

Examples of the surfactant include known anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants. Further, fluorine-based and silicone-based nonionic surfactants can be used in the same manner.
Surfactant may be used individually by 1 type, or may use 2 or more types together.
Although the usage-amount of surfactant does not need to specifically limit, it is preferable that it is 0.01-20 mass% with respect to the total mass of a rinse liquid, and it is more preferable that it is 0.05-10 mass%.

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.

The Shore A hardness of the relief layer of the relief printing plate is preferably 50 ° or more and 90 ° or less. 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.
The Shore A hardness in this specification is measured based on the Shore A hardness specified in JIS K6253, and an indenter (called a push needle or an indenter) is pushed into the surface of the object to be measured for deformation. It is a value measured by a type A durometer (spring type rubber hardness meter) that measures the amount (indentation depth) and digitizes it. In addition, the test piece uses what laminated | stacked 6 sheets of thickness 1mm, and the measurement temperature shall be 25 degreeC.

  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.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. Unless otherwise specified, “part” is based on mass.

Example 1
1. Preparation of resin composition for laser engraving The components shown in Table 1 below were mixed, and kept at 70 ° C. and degassed under reduced pressure while stirring to prepare a resin composition for laser engraving.
・ (Component A) Exothermic agent: 7 parts ・ (Component B) Binder polymer: 50 parts ・ (Component C) Crosslinking agent (alkoxysilane): 15 parts ・ (Component D) Polymerizable compound: 15 parts ・ (Component E) Polymerization initiator: 1 part. (Component F) Photothermal conversion agent: 5 parts. (Component G) Plasticizer: 20 parts. (Component H) Fragrance: 1 part. Catalyst: 1,8-diazabicyclo [5.4.0. ] Undec-7-ene: 0.4 parts Propylene glycol monomethyl ether acetate (PGMEA) was added to the above components to make the total mass of the resin composition for laser engraving 200 parts.

2. Preparation of relief printing plate precursor for laser engraving The resin composition for laser engraving is applied on PET (polyethylene terephthalate), heated at 90 ° C. for 8 hours, and thermally crosslinked to have a relief forming layer having a thickness of 1.28 mm. A relief printing plate precursor for laser engraving was obtained.

3. Production of relief printing plate (laser engraving) and evaluation Laser equipped with semiconductor laser with fiber (FC-LD) SDL-6390 (JDSU, wavelength: 915 nm) with a maximum output of 8.0 W as a semiconductor laser engraving machine A recording device was used. A 1 cm square solid part was raster engraved with a semiconductor laser engraving machine under conditions of laser output: 7.5 W, head speed: 409 mm / second, pitch setting: 2,400 DPI. There was no change in the thickness of the relief layer.
Moreover, when the Shore A hardness of the relief layer was measured by the above-mentioned measuring method, it was 71 °.

  The “sculpture depth” of the relief layer was measured as follows. Here, “sculpture depth” refers to the difference between the engraved position (height) and the unengraved position (height) when the cross section of the relief layer is observed. The “engraving depth” in this example was measured by observing the cross section of the relief layer with an ultra-deep color 3D shape measuring microscope VK9510 (manufactured by Keyence Corporation). A large engraving depth means high engraving sensitivity.

(Examples 2-38 and Comparative Examples 1-14)
Using the components shown in Table 1, the resin composition for laser engraving, the relief printing plate precursor for laser engraving, and the relief printing plate were prepared in the same manner as in Example 1, and Examples 2-38 and Comparative Examples 1- Each of 14 was obtained. Table 1 shows the results of measuring the engraving depth, relief layer thickness, and Shore A hardness of each relief printing plate obtained.

(Examples 39 to 76 and Comparative Examples 15 to 28)
Using each component shown in Table 2, the resin composition for laser engraving, the relief printing plate precursor for laser engraving, and the relief printing plate were prepared in the same manner as in Example 1, and Examples 39 to 80 and Comparative Examples 15 to Each of 29 was obtained.
In Examples 39 to 80 and Comparative Examples 15 to 29, as a carbon dioxide laser (CO ₂ laser) engraving machine, engraving by laser irradiation was performed using a high-quality CO ₂ laser marker ML-9100 series (manufactured by Keyence Corporation). ) Was used. After peeling the protective film from the printing plate precursor for laser engraving, a 1 cm square solid part was raster engraved with a carbon dioxide laser engraving machine under the conditions of output: 12 W, head speed: 200 mm / sec, pitch setting: 2,400 DPI . There was no change in the thickness of the relief layer.
Table 2 shows the results of measuring the engraving depth, relief layer thickness, and Shore A hardness of each relief printing plate obtained.

(Examples 77 to 80 and Comparative Example 29)
Using each component shown in Table 2, a resin composition for laser engraving was prepared in the same manner as in Example 1.
The above resin composition for laser engraving is applied on PET (polyethylene terephthalate), heated at 90 ° C. for 3 hours, and exposed to the whole surface with an ultrahigh pressure mercury lamp (manufactured by Oak Co., Ltd.) having a light source in the ultraviolet region (exposure amount: 4). , 000 mJ / cm ² ).
In Examples 77 to 80 and Comparative Example 29, as a carbon dioxide laser (CO ₂ laser) engraving machine, engraving by laser irradiation was performed using a high-quality CO ₂ laser marker ML-9100 series (manufactured by Keyence Corporation). Using. After peeling the protective film from the printing plate precursor for laser engraving, a 1 cm square solid part was raster engraved with a carbon dioxide laser engraving machine under the conditions of output: 12 W, head speed: 200 mm / sec, pitch setting: 2,400 DPI .
Table 2 shows the results of measuring the engraving depth, relief layer thickness, and Shore A hardness of each relief printing plate obtained.

The contents of each component described in Table 1 and Table 2 are as follows.
<(Component A) at least one exothermic agent selected from the group consisting of hydrazide compounds, nitro compounds, nitroso compounds, and tetrazole compounds>
A-1: 2,4,6-triisopropylbenzenesulfonyl hydrazide (manufactured by Tokyo Chemical Industry Co., Ltd.) Hydrazide value: 3.35 meq / g
A-2: 2-mesitylenesulfonyl hydrazide (manufactured by Tokyo Chemical Industry Co., Ltd.) hydrazide value: 4.67 meq / g
A-3: Benzenesulfonyl hydrazide (manufactured by Tokyo Chemical Industry Co., Ltd.) Hydrazide value: 5.81 meq / g
A-4: 1,5-diphenylcarbonohydrazide (manufactured by Tokyo Chemical Industry Co., Ltd.) Hydrazide value: 8.25 meq / g
A-5: 3 ′, 6′-bis (diethylamino) -2- (4-nitrophenyl) spiro [isoindole-1,9′-xanthen] -3-one (manufactured by Tokyo Chemical Industry Co., Ltd.) Nitro Value: 1.78 meq / g
A-6: 2-bromo-4-nitroanisole (manufactured by Tokyo Chemical Industry Co., Ltd.) Nitro value: 4.31 meq / g
A-7: 3,5-dinitrobenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) Nitro value: 9.43 meq / g
A-8: 2,4,6-tri-tert-butylnitrosobenzene (manufactured by Tokyo Chemical Industry Co., Ltd.) Nitroso value: 3.63 meq / g
A-9: 4-nitrosolesorcinol-1-monomethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) Nitroso value: 6.53 meq / g
A-10: Nitrosobenzene (manufactured by Tokyo Chemical Industry Co., Ltd.) Nitroso value: 9.34 meq / g
A-11: 1- (4-Methoxyphenyl) -5-mercaptotetrazole (manufactured by Tokyo Chemical Industry Co., Ltd.) Tetrazole value: 4.80 meq / g
A-12: 5-phenyl-1H-tetrazole (manufactured by Tokyo Chemical Industry Co., Ltd.) Tetrazole value: 6.84 meq / g
A-13: 5,5′-bistetrazole piperazine (Certetra BHT-PIPE, manufactured by Eiwa Chemical Industry Co., Ltd.) Tetrazole value: 8.88 meq / g
<(Component B) Binder polymer having a glass transition temperature (Tg) of 20 ° C. or higher>
B-1: Polyvinyl butyral (Denka Butyral # 3000-2, manufactured by Denki Kagaku Kogyo Co., Ltd.), Tg = about 68 ° C.
B-2: polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., Gohsenal T-215), Tg = about 85 ° C.
B-3: Polyvinyl acetate (manufactured by Alfa Aesar), Tg = about 32 ° C.
B-4: Polyamide (Amilan CM1017 manufactured by Toray Industries, Inc.), Tg = about 48 ° C.
B-5: Blemmer PME-100 (manufactured by NOF Corporation) / copolymer of 2-hydroxyethyl methacrylate = 50/50, comparative example, Tg = about 7 ° C.
B-6: Styrene butadiene rubber (manufactured by JSR Corporation, TR2000) (comparative example, Tg = −50 ° C.)
<(Component C) Compound having hydrolyzable silyl group and / or silanol group (crosslinking agent)>

＜（成分Ｄ）重合性化合物＞
・Ｄ−１：グリセロールジメタクリレート（東京化成工業（株）製）
・Ｄ−２：１，６−ヘキサンジオールジアクリレート（東京化成工業（株）製）
＜（成分Ｅ）重合開始剤＞
・Ｅ−１：ｔｅｒｔ−ブチルペルオキシベンゾエート（日油（株）製、パーブチルＺ）
・Ｅ−２：２，２’−アゾビス（２，４−ジメチルバレロニトリル）（和光純薬工業（株）製、Ｖ−６５）
・Ｅ−３：１−ヒドロキシシクロヘキシルフェニルケトン（チバジャパン（株）製、ＩＲＧＡＣＵＲＥ１８４）
＜（成分Ｆ）光熱変換剤＞
・Ｆ−１：ケッチェンブラック（ライオン（株）製、ＥＣ６００ＪＤ）
・Ｆ−２：カーボンブラック（東海カーボン（株）製、Ｎ３３０、ＨＡＦカーボン）
＜（成分Ｇ）可塑剤＞
・Ｇ−１：ジエチレングリコール（東京化成工業（株）製）
・Ｇ−２：クエン酸トリブチル（東京化成工業（株）製）
＜（成分Ｈ）香料＞
・Ｈ−１：バニリン（和光純薬工業（株）製）
・Ｈ−２：ｌ−メントール（和光純薬工業（株）製）

<(Component D) polymerizable compound>
D-1: Glycerol dimethacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
D-2: 1,6-hexanediol diacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)
<(Component E) Polymerization initiator>
E-1: tert-butyl peroxybenzoate (manufactured by NOF Corporation, perbutyl Z)
E-2: 2,2′-azobis (2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd., V-65)
E-3: 1-hydroxycyclohexyl phenyl ketone (Ciba Japan Co., Ltd., IRGACURE 184)
<(Component F) photothermal conversion agent>
F-1: Ketjen Black (Lion Corporation, EC600JD)
・ F-2: Carbon black (manufactured by Tokai Carbon Co., Ltd., N330, HAF carbon)
<(Component G) Plasticizer>
G-1: Diethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.)
G-2: Tributyl citrate (manufactured by Tokyo Chemical Industry Co., Ltd.)
<(Component H) Fragrance>
・ H-1: Vanillin (Wako Pure Chemical Industries, Ltd.)
・ H-2: l-Menthol (Wako Pure Chemical Industries, Ltd.)

Claims (14)

(Component A) at least one exothermic agent selected from the group consisting of hydrazide compounds, nitro compounds, nitroso compounds, and tetrazole compounds, and
(Component B) having a relief forming layer containing a binder polymer having a glass transition temperature (Tg) of 20 ° C. or higher on the support,
The relief printing plate precursor for laser engraving, wherein the content of the component A with respect to the total solid content of the relief forming layer is 1 to 20% by mass.   The relief printing plate precursor for laser engraving according to claim 1, wherein Component B is an acrylic resin and / or polyvinyl acetal.   The relief printing plate precursor for laser engraving according to claim 1, wherein the relief forming layer further contains (Component C) 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 3, wherein the relief forming layer further comprises (Component D) a polymerizable compound.   The relief printing plate precursor for laser engraving according to any one of claims 1 to 4, wherein the relief forming layer further contains (Component E) a polymerization initiator.   The relief printing plate precursor for laser engraving according to any one of claims 1 to 5, wherein the relief forming layer further contains (Component F) a photothermal conversion agent.   The relief printing plate precursor for laser engraving according to any one of claims 1 to 6, wherein the relief forming layer further contains a (component G) plasticizer.   The relief printing plate precursor for laser engraving according to any one of claims 1 to 7, wherein the relief-forming layer further contains a (component H) fragrance.   The relief printing plate precursor for laser engraving according to claim 1, which is a flexographic printing plate precursor. (1) 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 9 by light and / or heat, and
(2) An engraving step of forming a relief layer by laser engraving a crosslinked relief forming layer, and a method for making a relief printing plate.   The method for making a relief printing plate according to claim 10, wherein the crosslinking step is a step of crosslinking by heat. A relief printing plate produced by the plate making method of a relief printing plate according to claim 10 or 11.   The relief printing plate according to claim 12, wherein the thickness of the relief layer is from 0.05 mm to 10 mm.   The relief printing plate according to claim 12 or 13, wherein the Shore A hardness of the relief layer is from 50 ° to 90 °.