JP2002166669A - Photopolymerizable lithographic printing plate for printing and developing near infrared laser exposure, and method for platemaking for printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photopolymerizable lithographic printing plate for printing and developing near infrared laser exposure having a high sensitivity and excellent visible picture properties, and a method for platemaking the same. SOLUTION: The photopolymerizable lithographic printing plate for printing and developing near infrared laser exposure comprises a photosensitive layer containing (A) an ethylenic compound, (B) a cyanine sensitizing dye cation and/or a phthalocyanine sensitizing dye having a structure in which a heterocyclic ring is coupled via a polymethine chain, and (C) an organic boron anion and/or a halomethyl group-containing compound and provided on a hydrophilized support. A releasing strength of a gum tape from the hydrophilized support obtained by a method for measuring the releasing strength of the gum tape is 500 g/cm or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive lithographic printing plate for printing and developing near-infrared laser exposure and a method for making the same. More specifically, the present invention relates to a novel lithographic printing plate capable of forming a photocurable photosensitive image without requiring an alkali developing treatment, and a plate making method thereof.

[0002]

2. Description of the Related Art Conventional photosensitive lithographic printing plates are prepared by forming a negative photosensitive layer such as a diazo resin, a photocrosslinkable polymer, a photopolymerizable composition, or a benzoquinonediazide, A positive-type photosensitive layer such as quinonediazide is applied, and a polyvinyl alcohol layer is formed as an oxygen barrier layer on the photosensitive layer, if necessary.

In order to form a photosensitive image on such a photosensitive lithographic printing plate (plate making), after exposing the printing plate imagewise, an inorganic alkali agent such as sodium silicate or sodium carbonate or diethanolamine, triethanolamine or triethanolamine is used. Using an alkaline developer containing an organic alkali agent such as ethanolamine, immersing the printing plate in this developer and applying a physical stimulus such as a brush to the photosensitive layer in the case of a negative photosensitive layer. The exposed portion is dissolved, and in the case of a positive photosensitive layer, the exposed portion is dissolved and removed to obtain a photosensitive image on the support.

When an ink liquid comprising an emulsion of a lipophilic printing ink and a printing dampening solution is supplied to the surface of the printing plate on which an image has been formed as described above, the exposed surface of the hydrophilic support and the photosensitive image are exposed. The printing ink selectively forms on the photosensitive image and the water selectively adheres on the exposed hydrophilic support surface, thereby forming a printing ink image. A printed matter can be obtained by transferring the printing ink image to an image receiving paper.

The alkali developing solution used in the above plate making process usually requires 10 to 20 L (liter) with respect to an automatic developing apparatus in order to obtain a uniform image. Generally, the same developer is repeatedly used for developing a large number of photosensitive lithographic printing plates in order to reduce the amount of the alkaline developer used. Over time, the repeatedly used alkaline developer is degraded by the photosensitive layer composition dissolved in the solution and oxygen in the air with the elapse of time, and is likely to cause poor development. In order to suppress the deterioration of the alkali developer, a complicated operation for additionally replenishing the alkali developer having a high concentration is required. Even when such a high-concentration alkaline developing solution is replenished, it has been necessary to replace it with a new solution once every several weeks in a normal plate making factory.

When the new solution is replaced, the waste solution of the used alkali developer is discharged. However, in recent years, from the viewpoint of protection of the marine environment, it has become difficult to discard the used alkali developer in the ocean. Disposal of alkaline developers has long been an important issue in the printing arts.

For these reasons, development of a photosensitive lithographic printing plate which does not require development with an alkali developing solution has been promoted. Is insufficient, resulting in poor image quality at the time of printing; lipophilic image area has insufficient durability and long-term printing operation is not possible; or hydrophilic image formation The layers were easily scratched and easily worn away;

To solve such a problem, Japanese Patent Application Laid-Open No. 8-48020 discloses an image forming layer having a lipophilic, radiation-absorbing and heat-sensitive layer formed on a support having a porous hydrophilic surface. A technique for making a lithographic printing plate by the following method using the photosensitive lithographic printing plate described above is described.

(1) The photosensitive lithographic printing plate is imagewise exposed, and heat is generated in the exposed area to enhance the adhesiveness between the image forming layer in the exposed area and the support. The layer is peeled off, exposing the porous hydrophilic surface.

(2) In a state where the transfer sheet having the image forming layer and the printing plate support are in close contact with each other, the image forming layer is irradiated with infrared light to be absorbed and converted into heat, and the image forming layer is transferred to the transfer sheet. To a printing plate support. Alternatively, the imagewise layer of the photosensitive lithographic printing plate provided in advance on the printing plate support is similarly irradiated with light and changed to heat to enhance the adhesion between the image forming layer and the printing plate support, The unexposed portion of the image forming layer is peeled off.

Further, Japanese Patent Application Laid-Open No. 10-333321,
JP-A-10-3166 and US Pat. No. 6,149,929 provide a photopolymerizable layer sensitive to ultraviolet light or visible light on a printing plate support or on a printing plate support provided with a hydrophilic polymer layer. A photosensitive lithographic printing plate which is mounted on a printing press after image exposure by reducing the adhesiveness between the photosensitive layer and the support to a certain extent, and removing non-image portions using a masking tape or the like. Forming a light-cured printed image on a support (on a printing plate) by performing normal printing without removing or removing the unexposed portion of the printing plate together with a printing ink onto a rubber blanket roller. This publication describes a print-developable photosensitive printing plate capable of forming a printing plate and a method of making the plate.

However, since the photopolymerizable layer of the printing plate described in each of the above documents is sensitive to ultraviolet light or visible light, it is usually used on a printing machine installed in a room under a white light. It was difficult to handle. Along with this,
With the progress of digital image processing in recent years, there has been a demand for a printing plate capable of printing and developing that has high sensitivity to near-infrared semiconductor laser light and that is easy to handle (has a safelight characteristic) even under white light. I have.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photopolymerizable lithographic printing plate which does not require an alkali developing solution and has high sensitivity to light in the near infrared region. Also,
Another object of the present invention is to provide a printable photopolymerizable lithographic printing plate that can be handled even under a white light, and a method of making the plate.

[0014]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a photosensitive layer containing a specific photopolymerization system is provided on a hydrophilic and low-adhesive support. Have been found, and the present invention has been achieved.

That is, the gist of the present invention is to provide (A) an ethylenically unsaturated compound, (B) a cyanine sensitizing dye having a structure in which a heterocyclic ring is bonded via a polymethine chain, and / or a phthalocyanine sensitizing dye. (C) a photosensitive layer containing an organic boron anion and / or a compound containing a halomethyl group,
A photopolymerizable lithographic printing plate for print development near-infrared laser exposure provided on a hydrophilically treated support, from the hydrophilically treated support of a gum tape determined by a peel strength measurement method using a gum tape. Of a photopolymerizable lithographic printing plate for print-developed near-infrared laser exposure, which has a peel strength of 500 g / m or less.

Another gist of the present invention is that the photosensitive layer of the photopolymerizable lithographic printing plate for printing and developing near-infrared laser exposure is image-exposed to near-infrared light to cure the photosensitive layer imagewise. After the exposure, a method of forming a photocurable photosensitive image by removing the unexposed portion of the photosensitive layer from the support, mounting the photopolymerizable lithographic printing plate after image exposure on a plate cylinder of a printing press, When the dampening water and the printing ink are supplied onto the photosensitive layer of the photopolymerizable lithographic printing plate to transfer the ink to the roller surface of a blanket roller, the unexposed portion is used together with the ink to utilize the adhesiveness of the ink. And transferring to a roller surface of a blanket roller to remove the unexposed portion from the support. The present invention also provides a method for making a photopolymerizable lithographic printing plate for printing and developing near-infrared laser exposure.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The hydrophilic support used in the present invention is in a state where the surface is covered with a thin film of water (wet state) by fountain solution supplied at the time of printing, and comes into contact with the printing ink in an emulsion state. A function of preventing the attachment of lipophilic ink particles and forming a non-image portion on printed matter,
At the time of printing, the photosensitive layer applied on the hydrophilized surface is easily transferred and removed onto the blanket cylinder by the adhesive force with the printing ink at the time of printing.

As a hydrophilic support exhibiting such a function, a gum tape for peeling a gum tape from the support determined by a method of measuring a gum tape peel strength described in JP-A-10-333321 is used. It is necessary that the peel strength is 500 g / cm or less. Also,
The peel strength of the gum tape when the photosensitive layer after the exposure is peeled off is preferably 150 g / cm or more, particularly preferably more than 200 g / cm. If the peel strength is less than 150 g / cm, the printing durability may be poor.

More specifically, the following (a) or (b) is mentioned as the hydrophilic support according to the present invention.

(A) an aluminum plate (hereinafter referred to as “aluminum plate”) whose surface is roughened (grained) by various methods and hydrophilized by anodic electrolytic treatment or the like; (b) paper, Various paper boards such as synthetic paper, coated paper, art paper,
A metal plate such as an aluminum plate, a copper plate, an iron plate, and a stainless steel plate, a wooden plate, a plastic plate such as a polyethylene terephthalate sheet, a polypropylene sheet, a polyethylene sheet, and the like, and a support having excellent dimensional stability are provided with hydrophilicity or water. With a swellable hydrophilic polymer layer; graining of the aluminum plate of (a) improves the adhesiveness of the photosensitive layer formed on the support, and water-receiving properties of the non-image area of the printing plate This is done to improve. This graining affects both the performance and durability of the printing plate, and the quality of the graining is an important factor in determining the overall quality of the printing plate. By forming fine and uniform grain without pits, the resulting printing plate is given essentially good printing performance.

As such a graining method, mechanical and electric graining methods are well known and widely used in the production of lithographic printing plates. Good results can be obtained by using electrolytic graining, referred to as electrochemical graining or electrochemical roughening.

Numerous electrolytic graining methods have already been proposed for the production of lithographic printing plates, for example, US Pat. Nos. 3,755,116, 3,887,447,
Nos. 3,935,080 and 4,087,341
No. 4,201,836, No. 4,272,34
No. 2, No. 4,294,672, No. 4,301,2
No. 29, No. 4,396,468, No. 4,427,
No. 500, No. 4,468,295, No. 4,47
No. 6,006, No. 4,482,434, No. 4,5
No. 45,875, No. 4,548,683, No. 4,
Nos. 564,429, 4,581,996, 4,618,405, 4,735,696, 4,897,168 and 4,919,774. Has been described.

As the anodic electrolysis treatment after graining, an anodic oxidation treatment using an acid such as sulfuric acid or phosphoric acid is performed, and after this anodic oxidation treatment, it is preferable to use thermal silicate (silicone).
) or an electro-silicate treatment is performed.

The subsequent roughening treatment (graining treatment) includes mechanical treatment methods such as a ball polishing method, a brush polishing method, a blast polishing method, a honing polishing method and a puff polishing method, an electrolytic etching method, and a chemical etching method. It is done according to the usual law such as the law. Among them, an electrolytic etching method of performing electrolysis by alternating current or direct current in a hydrochloric acid or nitric acid electrolytic solution is preferable,
At this time, when the acid concentration is 0.1 to 5% by weight, the applied voltage is 1 to 50%.
V, current density 10-200 A / dm ² , electric quantity 100-
It is preferable that the heat treatment be performed under the conditions of 2000 c / dm ² and a temperature in the range of about 10 to 50 ° C.

Next, the support roughened by the electrolytic etching method is used to remove an acid such as sulfuric acid, persulfuric acid, phosphoric acid, nitric acid, hydrochloric acid, hydrofluoric acid, etc. in order to remove the surface smut and control the pit shape. Alternatively, desmutting treatment is preferably performed by dipping in an aqueous solution of an alkali such as sodium hydroxide or potassium hydroxide.

The subsequent anodizing treatment is performed by using an aqueous solution containing one or more of sulfuric acid, oxalic acid, phosphoric acid, chromic acid, malonic acid or the like as an electrolytic solution, and performing electrolysis using an aluminum plate as an anode. The amount of the oxide film thus formed is usually 1 to 50 mg / dm ² . In the middle, a preferred method of the sulfuric acid or / and aqueous electrolytic solution of phosphoric acid, specifically, for example, an acid concentration of 10 to 50 wt%, a current density of 1 to 60 A / dm ^2, temperature 5-50 ° C
For about 5 to 60 seconds.

In the subsequent water washing treatment, tap water, ground water, or the like is used as it is or after softening.
Shower at a temperature of about 0 ° C. for a time of about 1 second to 5 minutes,
It is performed by spraying, dipping, coating, or the like. The surface roughness of the support is generally 0.3 to 1.0 μm, preferably about 0.4 to 0.8 μm in terms of average roughness Ra specified in JIS B0601.

As a method for hydrophilizing a surface of an aluminum plate by anodizing treatment and silicate treatment, it is already widely known.

For example, US Pat. No. 2,594,289 discloses a patent relating to a method of anodizing a lithographic printing plate.
No. 2,703,781, No. 3,227,63
No. 9, No. 3,511,661, No. 3,804,7
No. 31, No. 3,915, 811 and No. 3,988,
Nos. 217, 4,022,670 and 4,11
Nos. 5,211 and 4,229,266 and 4,
No. 647,346.

As the coating material used in the surface hydrophilization treatment, in addition to the above silicates, hydrophilic polymers such as polyvinylphosphonic acid, polyacrylic acid, cellulose, polyvinyl alcohol, polyacrylamide or derivatives thereof, zirconate, Titanate can be used, and as patents relating to such a surface hydrophilization treatment, US Pat. Nos. 2,714,066 and 3,860,426
No. 4,427,765, No. 3,181,46
No. 1, No. 3220, 832, No. 3, 265, 50
No. 4, No. 3276,868, No. 3,549, 36
No. 5, No. 4,090,880, No. 4,153, 4
No. 61, No. 4,376,914, No. 4,383
No. 987, No. 4,399,021, No. 4,42
7,765, 4,427,766, 4,4
No. 48,647, No. 4,452,674, No. 4,
Nos. 458,005, 4,492,616, 4,578,156, 4,689,272, 4,935,332, and EP 190,190.
No. 643.

The thickness of the thus obtained hydrophilically treated aluminum plate is 0.1 to 1 mm, particularly 0.15 to 1 mm.
It is preferably 0.5 mm, especially 0.15 to 0.4 mm.

When a hydrophilic polymer layer is provided on the various supports described in (b) above, the hydrophilic polymer layer may contain, if necessary, a hydrophilic polymer cured with a crosslinking agent or the like in order to maintain the hydrophilicity. The binder polymer can be contained at 5 to 100% by weight, preferably 20 to 95% by weight, more preferably 40 to 90% by weight based on the total solid content of the hydrophilic polymer layer.

Here, the hydrophilic binder polymer is
As a side chain to a polymer composed of carbon-carbon bonds,
A networked polymer containing one or more hydrophilic functional groups such as a carboxyl group, an amino group, a phosphoric acid group, a sulfonic acid group, or a salt, a hydroxyl group, an amide group, and a polyoxyethylene group, or , Carbon atom, carbon-
Any of the carbon bonds is a carboxyl group, an amino group, a phosphoric acid group, a sulfonic acid group, or a carboxyl group, an amino group, a phosphoric acid group, Salt, a hydroxyl group, an amide group, a polymer containing one or more hydrophilic functional groups such as a polyoxyethylene group, specifically,
Poly (meth) acrylate, polyoxyalkylene, polyurethane, epoxy ring-opening addition polymerization, poly (meth) acrylic acid, poly (meth) acrylamide, polyester, polyamide, polyamine, polyvinyl, etc. Polymers such as saccharides and cellulose derivatives are exemplified.

Of these, a hydroxyl group on the side chain of the segment,
A carboxyl group or an alkali metal salt thereof, an amino group or a hydrogen halide salt thereof, a sulfonic acid group or an amine thereof,
Alkali metal salts, alkaline earth metal salts, those having a combination of two or more of any one of amide groups, and further having a polyoxyethylene group as a part of these hydrophilic functional groups and main chain segments. Those having an overlap are preferred because of their high hydrophilicity. Further, those having a urethane bond or a urea bond in the main chain or side chain of the hydrophilic binder polymer are more preferable because they have high printing durability in a non-image area as well as hydrophilicity.

Hereinafter, the hydrophilic polymer layer containing the hydrophilic binder polymer of the present invention will be described more specifically. In this specification, “(meth) acrylate” indicates “acrylate and / or methacrylate”, and “(meth) acryl” indicates “acryl and / or methacryl”. In addition, the hydrophilic binder polymer according to the present invention may contain various other components described below as necessary.

In order to form a hydrophilic polymer layer containing the hydrophilic binder polymer according to the present invention, for example, first,
(Meth) acrylic acid or its alkali and amine salts,
Itaconic acid or its alkali, amine salt, 2-hydroxyethyl (meth) acrylate, (meth) acrylamide, N-monomethylol (meth) acrylamide,
N-dimethylol (meth) acrylamide, 3-vinylpropionic acid or an alkali or amine salt thereof, vinylsulfonic acid or an alkali or amine salt thereof, 2-sulfoethyl (meth) acrylate, polyoxyethylene glycol mono (meth) acrylate, 2- Hydroxyl group such as acrylamide-2-methylpropanesulfonic acid, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, allylamine or its halogenated hydrochloride, carboxyl group or its salt, sulfonic acid group or its salt, phosphoric acid or A hydrophilic homo- or copolymer is synthesized using at least one selected from a hydrophilic monomer having a hydrophilic group such as a salt, an amide group, an amino group, and an ether group.

A hydrophilic binder polymer having a functional group such as a hydroxyl group, a carboxyl group, an amino group or a salt thereof, or an epoxy group utilizes these functional groups to add ethylene such as a vinyl group, an allyl group, and a (meth) acryl group. A polymer containing an unsaturated group into which a polymerizable unsaturated group or a ring-forming group such as a cinnamoyl group, a cinnamylidene group, a cyanosinnamylidene group or a p-phenylenediacrylate group is introduced is obtained. If necessary, a monofunctional or polyfunctional monomer copolymerizable with the unsaturated group, a polymerization initiator described below, and other components described below are added, and the mixture is dissolved in an appropriate solvent to prepare a coating solution. This is applied on a support and subjected to three-dimensional crosslinking after drying or also as drying.

The hydrophilic binder polymer containing an active hydrogen such as a hydroxyl group, an amino group or a carboxyl group may be used together with an isocyanate compound or a blocked polyisocyanate compound and other components described below together with an active hydrogen such as methyl ethyl ketone, propylene glycol monomethyl ether acetate, cyclohexanone, and the like. A coating solution is prepared by adding the solution to a non-containing solvent, and the solution is coated on a support, and dried or three-dimensionally crosslinked after drying.

A monomer having a glycidyl group such as glycidyl (meth) acrylate and a carboxyl group such as (meth) acrylic acid can be used in combination with the copolymer component of the hydrophilic binder polymer. Is a hydrophilic binder polymer having a glycidyl group as a crosslinking agent, α, X-alkane or alkenedicarboxylic acid such as 1,2-ethanedicarboxylic acid or adipic acid, 1,2,3-propanetricarboxylic acid, Polycarboxylic acids such as merit acid, 1,2-ethanediamine, diethylenediamine, diethylenetriamine, polyamine compounds such as α, X-bis- (3-aminopropyl) -polyethylene glycol ether, ethylene glycol, propylene glycol, diethylene glycol, tetraethylene A polyhydroxy compound such as oligoalkylene or polyalkylene glycol such as tylene glycol, trimethylolpropane, glycerin, pentaerythritol and sorbitol can be used, and three-dimensional cross-linking can be carried out using a ring opening reaction with these.

The hydrophilic binder polymer having a carboxyl group or an amino group may be used as a crosslinking agent such as ethylene or propylene glycol diglycidyl ether, polyethylene or polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether,
Three-dimensional crosslinking can be performed using an epoxy ring-opening reaction using a polyepoxy compound such as 1,6-hexanediol diglycidyl ether and trimethylolpropane triglycidyl ether.

Polysaccharides such as cellulose derivatives, polyvinyl alcohol or partially saponified products thereof, glycidol homo- or copolymers, or hydrophilic binder polymers based on these are utilized by utilizing the hydroxyl groups contained therein, and the above-mentioned functional groups capable of undergoing a crosslinking reaction. Groups can be introduced and three-dimensionally cross-linked by the methods described above.

A polyol or polyamine containing a hydroxyl group or an amino group at the polymer terminal, such as polyoxyethylene glycol, and 2,4-tolylene diisocyanate;
Using a polymer in which an ethylene addition polymerizable unsaturated group or a ring-forming group is introduced into a hydrophilic polyurethane precursor synthesized from a polyisocyanate such as 2,6-tolylene diisocyanate, 1,6-hexamethylene diisocyanate, or isophorone diisocyanate. Three-dimensional crosslinking can be performed by the method described above.

Here, when the synthesized hydrophilic polyurethane precursor has an isocyanate group terminal, glycerol mono (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, N -Monomethylol (meth) acrylamide, N-dimethylol (meth) acrylamide,
(Meth) acrylic acid, cinnamic acid, a compound having an active hydrogen such as cinnamic alcohol, and having a hydroxyl group or amino group terminal, (meth) acrylic acid, glycidyl (meth) acrylate, 2-isocyanatoethyl ( (Meth) acrylate and the like.

Further, after applying a polybasic acid and a polyol or a polybasic acid and a polyamine, a three-dimensional crosslinking is carried out by heating, or a water-soluble colloid-forming compound such as casein, glue or gelatin is three-dimensionally crosslinked by heating. A hydrophilic binder polymer having a structure may be formed.

In addition, hydroxyl groups such as homo- or copolymers synthesized from hydroxyl-containing monomers such as 2-hydroxyethyl (meth) acrylate and vinyl alcohol and allylamine, polysaccharides such as partially saponified polyvinyl alcohol and cellulose derivatives, and glycidol homo- or copolymers; There is also a method of forming a three-dimensionally crosslinked hydrophilic binder polymer by reacting a group-containing hydrophilic polymer with a polybasic acid anhydride having two or more acid anhydride groups in one molecule.

Here, polybasic acid anhydrides include ethylene glycol bis-anhydrotrimellitate, glycerol tris-anhydrotrimellitate,
3,3a, 4,5,9b hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-C] furan-1,3-dione, 3,3 ′,
4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride and the like are exemplified.

An active hydrogen-containing compound such as a polyamine or a polyol having an isocyanate group at the end thereof and an active hydrogen-containing compound such as a polyamine or a polyol are dissolved or dispersed in a solvent and coated on a support to remove the solvent. Can be cured at a temperature at which they do not break down to form a three-dimensional crosslink. In this case, hydrophilicity may be imparted by introducing a hydrophilic functional group into either or both segments and side chains of the polyurethane or the active hydrogen-containing compound. The segment expressing hydrophilicity and the functional group may be appropriately selected from those described above.

Here, polyisocyanate compounds that can be used include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, and 4,4 ′
-Diphenylmethane diisocyanate, 1,5-naphthalenediisocyanate, tolidine diisocyanate,
Examples thereof include 1,6-hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, lysine diisocyanate, triphenylmethane triisocyanate, and bicycloheptane triisocyanate.

In some cases, it is preferable to block (mask) the isocyanate group by a known method in order to prevent the isocyanate group from changing during handling before and after the coating step. In this case, for example, Keiji Iwata, "Plastic Materials Course Polyurethane Resin"
Sodium acid sulfite, aromatic secondary according to Nikkan Kogyo Shimbun (1974), pp. 51-52, "Polyurethane Resin Handbook" by Keiji Iwata, Nikkan Kogyo Shimbun (1987), pp. 98, 419, 423, 499, etc. Masking agents such as amines, tertiary alcohols, amides, phenols, lactams, heterocyclic compounds, and ketoxime can be used. Of these, isocyanate regeneration temperature is particularly low and hydrophilic is preferable, and examples thereof include sodium acid sulfite.

An addition-polymerizable unsaturated group may be introduced into any of the above-mentioned non-blocked or blocked polyisocyanates and used for strengthening crosslinking or reacting with lipophilic components. The degree of the degree of cross-linking such as the average molecular weight between cross-links varies depending on the type of segment used, the type and amount of the associative functional group, and the like, but may be determined according to the required printing durability. Normal,
The average molecular weight between crosslinks is set in the range of 500 to 50,000.
If this value is shorter than 500, it tends to be brittle. If it is longer than 50,000, it may be unfavorable because it swells with fountain solution and printing durability is impaired. On the balance between printing durability and hydrophilicity, the average molecular weight between crosslinks is 800 to 30,000, particularly 1000.
About 10,000 is practical.

The hydrophilic binder polymer of the present invention includes:
Further, the following monofunctional monomers and polyfunctional monomers may be used in combination.

In other words, Shinzo Yamashita, Tosuke Kaneko, “Crosslinking Agent Handbook”, Taiseisha (1981), Kiyomi Kato, “Ultraviolet Curing System”, published by Sogo Gijutsu Center (1989), Kiyomi Kato, “UV / EB Curing”. Handbook (raw material edition) "Polymer Publishing Association (1985), supervised by Kiyoshi Akamatsu," Practical technology of new photosensitive resin ", CMC, pp. 102-114 (198)
7), N, N'-methylenebisacrylamide, (meth) acryloylmorpholine, vinylpyridine, N-methyl (meth) acrylamide, N, N-
Dimethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminoneopentyl ( Meth) acrylate, N-vinyl-2-pyrrolidone, diacetone acrylamide, N
-Methylol (meth) acrylamide, p-styrene sulfonic acid and its salt, methoxytriethylene glycol (meth) acrylate, methoxy tetraethylene glycol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate (number average molecular weight of PEG 4
00), methoxypolyethylene glycol (meth) acrylate (PEG number average molecular weight 1000), butoxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, nonylphenoxy Ethyl (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, polyethylene glycol di (meth) acrylate (PEG having a number average molecular weight of 40
0), polyethylene glycol di (meth) acrylate (number average molecular weight of PEG 600), polyethylene glycol di (meth) acrylate (number average molecular weight of PEG 1)
000), polypropylene glycol di (meth) acrylate (number average molecular weight of PEG 400), 2,2-bis [4- (methacryloxyethoxy) phenyl] propane, 2,2-bis [4- (methacryloxy diethoxy) phenyl ] Propane, 2,2-bis [4- (methacryloxypolyethoxy) phenyl] propane or an acrylate thereof, β- (meth) acryloyloxyethyl hydrogendiene phthalate, β- (meth) acryloyloxyethyl hydrogen succinate, polyethylene Or polyphenylene glycol mono (meth) acrylate, 3-chloro-2-hydroxypropyl (meth)
Acrylate, 1,3-butylene glycol di (meth)
Acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropanetri (meth) acrylate, tetramethylolmethanetri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, Isobornia (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate,
Stearyl (meth) acrylate, isodecyl (meth)
Acrylate, cyclohexyl (meth) acrylate,
Tetrafurfuryl (meth) acrylate, benzyl (meth) acrylate, mono (2-acryloyloxyethyl) acid phosphate or its methacrylic body, glycerin mono- or di (meth) acrylate, tris (2-
(Acryloxyethyl) isocyanurate or its methacrylic body, N-phenylmaleimide, N- (meth) acryloxysuccinimide, N-vinylcarbazole, divinylethyleneurea, divinylpropyleneurea and the like.

The hydrophilic polymer layer used in the present invention has a particle size of 1 to improve the water retention of the dampening solution.
0-40 nm colloidal silica, particle size 10-100 n
m of colloidal alumina, acetic acid, formic acid, citric acid, tartaric acid, malic acid, carboxylic acid such as itaconic acid or a carboxylate alone or a mixture thereof with respect to the total solid content of the hydrophilic polymer layer is 0 to 90% by weight, preferably 0 to 80% by weight can be contained.

Further, in the hydrophilic polymer layer,
For the purpose of improving the coating properties of the photosensitive layer, a suitable surfactant is added to the total solid content of the hydrophilic polymer layer coating solution.
It can be contained at a blending ratio of 0.01 to 10% by weight.

The thickness of the hydrophilic polymer layer used in the present invention is 0.1 to 100 μm, preferably 0.2 to 50 μm.
m, more preferably 0.5 to 20 μm. In addition, the thickness of the various supports (b) forming such a hydrophilic polymer layer is 25 μm to 1 mm, particularly 50 to 500 μm.
m, particularly preferably 50 to 300 μm.

Further, between the support of the present invention and the photosensitive layer, if necessary, as described in US Pat. No. 6,014,929, JP-A-10-3166, etc. A release layer can be provided for the purpose of facilitating peeling of the non-image photosensitive layer from the support. The release layer is made of a material that is soluble or dispersible in a fountain solution, a printing ink or the like usually used on a printing press. Specifically, an organic polymer compound such as polyvinyl alcohol is preferably used. .0
It is applied to a film thickness of 1 to 5 mg / dm ² . In the case where the organic polymer compound having high hydrophilicity is used, the same treatment as the hydrophilizing treatment of the surface of the grain is performed, and the two effects of hydrophilizing and releasability can be achieved.

Next, in the present invention, a compound having at least one addition-polymerizable ethylenic double bond contained in the photosensitive layer formed on the hydrophilic support (hereinafter referred to as "ethylenic compound"). ) Will be described. The ethylenic compound as the component (A) of the photopolymerizable composition of the present invention is a monomer having an ethylenically unsaturated bond that undergoes addition polymerization and cures by the action of a photopolymerization initiation system (in addition, The meaning of the monomer in the present invention is a concept corresponding to a so-called polymer, and therefore includes not only a monomer in a narrow sense but also a dimer, a trimer, and an oligomer.) By penetrating into the unevenness or pores on the surface of the hydrophilic support and curing by light during exposure, it enhances the adhesion between the photosensitive layer and the hydrophilic support and has high film strength to withstand physical stimulation during printing. To provide a photosensitive layer, while
Before photocuring, the adhesive property to the hydrophilic support is relatively small, and the adhesive tape has the peel strength specified in the present invention.Therefore, in the unexposed portion of the photosensitive layer, the adhesiveness of the printing ink at the time of printing causes It is required that the material can be easily transferred to the surface of the blanket roller and removed from the hydrophilic support to expose the hydrophilic surface of the support.

In the present invention, as the ethylenic compound, an ethylenic compound having a urethane skeleton having the following specific structure, an esterified product of phosphoric acid and a compound containing a (meth) acryloyl group, or a hydroxy (mono / poly) It is preferable to use one or more alkyleneoxy (meth) acrylates (hereinafter, these three ethylenic compounds are referred to as “specific ethylenic compounds”).

The ethylenic compound having a urethane skeleton is characterized by having a urethane skeleton in the molecule, and has a function of exhibiting high adhesion to a support and high film strength. Among them, those having a partial structure represented by the following general formula (I) are preferably used.

[0060]

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(In the general formula (I), Y ¹ and Y ² each independently represent an acryloyl group or a methacryloyl group.
x represents an integer of 0 to 2, y represents an integer of 0 to 3, z
Represents an integer of 0 to 3. However, y + z−x = 1. A ³ represents an alkylene group having 1 to ³ carbon atoms or a direct bond. As the compound having the partial structure represented by the general formula (I), a urethane compound obtained by reacting an organic diisocyanate compound or a trimer thereof with a (meth) acryloyl group-containing hydroxy compound is usually used.

Examples of the organic diisocyanate compound include aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate, alicyclic diisocyanates such as cyclohexane diisocyanate and isophorone diisocyanate, and aromatic diisocyanates such as tolylene diisocyanate and diphenylmethane diisocyanate. Is mentioned. Also,
Examples of the (meth) acryloyl group-containing hydroxy compound to be reacted with the organic diisocyanate compound or a trimer thereof include those represented by the following general formula (II).

[0063]

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(In the formula (II), x, z, y, and A ³ have the same meanings as those in the general formula (I).) Such a (meth) acryloyl group-containing hydroxy compound is as follows. Is exemplified.

[0065]

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Representative urethane compounds obtained by reacting the above-mentioned organic diisocyanate compound or its trimer with a (meth) acryloyl group-containing hydroxy compound are represented by the following general formulas (III) to (VI). Show.

[0067]

Embedded image (In the formula (III), R ^{1 to} R ³ each independently represent the following)

Embedded image (In the above formula, k represents an integer of 1 to 10, preferably 5 to 7, and a represents 1 or 2. Y ¹ and Y ² each independently represent an acryloyl group or a methacryloyl group.)

[0068]

Embedded image (In the formulas (IV) and (V), R ⁴ and R ⁵ each independently represent the following)

Embedded image (In the above formula, j represents an integer of 1 to 3, preferably 1 or 2, a represents 1 or 2. Y ¹ and Y ² each independently represent an acryloyl group or a methacryloyl group.)

[0069]

Embedded image (In the formula (VI), h represents an integer of 1 to 10, preferably 5 to 7, and R ⁶ and R ⁷ each independently represent the following.)

Embedded image (In the above formula, a represents 1 or 2. Y ¹ and Y ² each independently represent an acryloyl group or a methacryloyl group.)

Preferred examples of the ethylenic compound having a urethane skeleton used in the present invention include the following compound E-
1 to E-11.

[0071]

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[0072]

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[0073]

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[0074]

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These ethylenic compounds having a urethane skeleton are used singly or as a mixture of two or more, and are usually used in an amount of 10 to 9 based on the total solid content of the photosensitive layer.
0% by weight, preferably 20 to 70% by weight. If the compounding ratio is less than 10% by weight, the printing durability is reduced, and if it is more than 90% by weight, the transferability of the unexposed photosensitive layer to the blanket roller is liable to be reduced. .

The phosphoric ester of the (meth) acryloyl group-containing compound among the specific ethylenic compounds is not particularly limited as long as it is an ester of phosphoric acid and the (meth) acryloyl group-containing compound. Include compounds represented by the following general formula (VII). Such a compound is effective in improving the sensitivity and printing durability, and in increasing the transferability of an unexposed portion to a blanket roller during printing. is there.

[0077]

Embedded image (In the general formula (VII), R ⁸ represents a hydrogen atom or a methyl group, n represents an integer of 1 to 25, and m represents 1 or 2.)

Among the compounds represented by the general formula (VII), those having n of 1 to 10 are particularly preferable in terms of improving the printing durability and the removability of the non-image area. General formula (VII)
Preferred specific examples of the compound represented by are methacryloxyethyl phosphate, bis (methacryloxyethyl) phosphate and the like.

Such a phosphoric ester compound is as follows.
The seeds are used alone or as a mixture of two or more kinds, and the content is usually 0.1 to 30% by weight, preferably 0.2 to 25% by weight of the total solids of the photosensitive layer. If the proportion is less than 0.1% by weight, the adhesiveness to the support and the transferability of the unexposed photosensitive layer will be poor.

Further, hydroxy (mono / poly) alkyleneoxy (meth) acrylate as a specific ethylenic compound has a function of improving adhesiveness, sensitivity, and transferability of an unexposed photosensitive layer. And those represented by the following general formula (VIII) are preferred.

[0081]

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(In the general formula (VIII), R ⁹ represents a hydrogen atom or a methyl group, A ⁶ represents an alkylene group having 1 to 6 carbon atoms which may be substituted by halogen, p represents an integer of 2 or more.) In the general formula (VIII), A ⁶ has 2 to 4 carbon atoms.
Is preferably an optionally branched alkylene group. When the alkylene group is substituted with halogen, the substituent is preferably a chlorine atom. More preferably, A ⁶ is an unsubstituted and optionally branched alkylene group having 2 or 3 carbon atoms, that is, polyethylene glycol mono (meth) acrylate or polypropylene glycol mono (meth) acrylate. In the general formula (VIII), p is not a problem as long as it is an integer of 2 or more. In particular, it is most preferable that p is from 5 to 50 in terms of adhesion to a support, sensitivity, and developability. preferable.

Such hydroxy (mono / poly)
The alkyleneoxy (meth) acrylate is used singly or as a mixture of two or more, and the content thereof is not particularly limited, but is usually 0.1 to 10% based on the total solid content of the photosensitive layer. 30% by weight, preferably 0.2 to
It is 25% by weight, more preferably 0.3 to 20% by weight. If this blending ratio is less than 0.1% by weight, the adhesion to the support and the transferability of the unexposed photosensitive layer are poor, and
If the amount is more than the percentage by weight, the sensitivity tends to deteriorate.

The phosphoric acid ester of the (meth) acryloyl group-containing compound and the hydroxy (mono / poly) alkyleneoxy (meth) acrylate compound as the specific ethylenic compound are effective in their respective functions. On the other hand, the phosphoric acid ester of a (meth) acryloyl group-containing compound should be applied to a grained grain that has not been subjected to hydrophilization of silicate and an aluminum plate that has only been subjected to anodic oxidation, as a hydrophilic support. Preferably, the hydroxy (mono / poly) alkyloxy (meth) acrylate compound is applied to a grained and anodized aluminum plate that has been subjected to a hydrophilization treatment with silicate as a hydrophilic support.

In the present invention, an ethylenic compound other than the above specific ethylenic compound may be used in combination.
In particular, it is desirable to use a polyfunctional ethylenic compound having two or more ethylenic double bonds together with the above specific ethylenic compound.

Examples of such polyfunctional ethylenic compounds include, for example, esters of aliphatic polyhydroxy compounds with unsaturated carboxylic acids, esters of aromatic polyhydroxy compounds with unsaturated carboxylic acids, aliphatic polyhydroxy compounds, aromatic polyhydroxy compounds, and aromatic polyhydroxy compounds. And esters obtained by an esterification reaction of a polyvalent hydroxy compound such as an aromatic polyhydroxy compound with an unsaturated carboxylic acid and a polyvalent carboxylic acid.

Here, the ester of the aliphatic polyhydroxy compound and the unsaturated carboxylic acid is not particularly limited, but ethylene glycol diacrylate, triethylene glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, Acrylic esters of aliphatic polyhydroxy compounds such as pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, glycerol acrylate, and these exemplified compounds Methacrylates instead of acrylates, and itaconates Instead itaconic acid esters, maleic acid esters, and the like was replaced with crotonic acid ester or maleate was replaced crotonate.

Examples of the ester of an aromatic polyhydroxy compound and an unsaturated carboxylic acid include hydroquinone diacrylate, hydroquinone dimethacrylate, resorcin diacrylate, resorcin dimethacrylate,
Acrylic esters and methacrylic esters of aromatic polyhydroxy compounds such as pyrogallol triacrylate.

The ester obtained by the esterification reaction of unsaturated carboxylic acid, polycarboxylic acid and polyhydroxy compound is not necessarily a single substance, but typical examples include acrylic acid and phthalic acid. Examples thereof include condensates of acid and ethylene glycol, condensates of acrylic acid, maleic acid and diethylene glycol, condensates of methacrylic acid, terephthalic acid and pentaerythritol, condensates of acrylic acid, adipic acid, butanediol and glycerin.

Other polyfunctional ethylenic compounds used in the present invention include epoxy acrylates such as an addition reaction product of a diepoxy compound and hydroxyethyl acrylate, acrylamides such as ethylenebisacrylamide, and allyls such as diallyl phthalate. Esters and vinyl group-containing compounds such as divinyl phthalate are effective.

Among the ethylenic compounds, polymers having an ethylenic double bond in the main chain include, for example, polyesters obtained by a polycondensation reaction between an unsaturated divalent carboxylic acid and a dihydroxy compound, and unsaturated divalent carboxylic acids. And polyamides obtained by a polycondensation reaction between amides and diamines. Polymers having an ethylenic double bond in the side chain are divalent carboxylic acids having a double bond in the side chain, for example, condensation of itaconic acid, propylidene succinic acid, ethylidene malonic acid and the like with a dihydroxy compound or a diamine compound. There are polymers. Further, a polymer having a functional group having a reactive activity such as a hydroxy group or a methyl halide group in a side chain, for example, polyvinyl alcohol, poly (2-hydroxyethyl methacrylate), polyepichlorohydrin, etc., and acrylic acid, methacrylic acid, crotonic acid A polymer obtained by a polymer reaction with an unsaturated carboxylic acid such as described above can also be suitably used.

The proportion of the component (A) in the entire photosensitive layer is preferably from 20 to 80% by weight, particularly preferably from 30 to 70% by weight, due to the content of other components described later. .

(B) Constituting the Photopolymerizable Composition of the Invention
Among the components, the cyanine-based sensitizing dye cation has a structure in which a heterocycle is bonded via a polymethine chain, and the phthalocyanine dye has a structure in which a heterocycle is bonded via a (aza) polymethine chain. But among these,
Those absorbing any light of 750 to 1200 nm are preferable, and among them, it is particularly effective to have a maximum absorption in a near infrared region of a wavelength range of 750 to 1200 nm. These cyanine-based sensitizing dye cations and phthalocyanine sensitizing dyes efficiently absorb light in the above-mentioned wavelength range, and transfer the photoexcitation energy to an organic boron anion or a halomethyl group-containing compound of the component (C) described below. While having a sensitizing function of decomposing the component (C) and generating an active radical that induces polymerization of the ethylenic compound of the component (A),
It is a compound that hardly absorbs light in the ultraviolet region, or has a substantially low response even when absorbed, and has a small effect of denaturing the composition depending on weak ultraviolet light contained in a white fluorescent lamp.

In the present invention, these cyanine dye cations include so-called cyanine dyes in a broad sense, in which a heterocyclic ring containing a nitrogen atom, an oxygen atom, a sulfur atom or the like is bonded by a polymethine (-CH =) n chain. A cation, specifically, for example, a quinoline-based (so-called cyanine-based)
Indole (so-called indocyanine), benzothiazole (so-called thiocyanine), iminocyclohexadiene (so-called polymethine), pyrylium, thiapyrylium, squarylium, croconium,
Azurenium-based dye cations are exemplified, among which quinoline-based, indole-based, benzothiazole-based, iminocyclohexadiene-based, pyrylium-based, and thiapyrylium-based dye cations are preferable. Here, the case where the cyanine dye cation forms an inner salt is also included.

In the present invention, among the cyanine-based dye cations, quinoline-based dye cations particularly include the following general formulas (IXa), (IXb), and (IX)
Those represented by c) are preferred.

[0096]

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[Formulas (IXa), (IXb) and (IX
In c), R ¹ and R ² are each independently an alkyl group optionally having a substituent, an alkenyl group optionally having a substituent, or an alkynyl group optionally having a substituent. Or a phenyl group which may have a substituent, wherein L ¹ is an optionally substituted tri, penta, hepta, nona,
Or a undecamethine group, and two substituents on the penta, hepta, nona, or undecamethine group are connected to each other to form a cycloalkene ring having 4 to 7 carbon atoms, a cycloalkenenone ring, a cycloalkenedione ring, or a cycloalkenethione. A ring may be formed, and the quinoline ring may have a substituent. In this case, two adjacent substituents may be connected to each other to form a fused benzene ring. ]

Here, when R ¹ and R ² in the formulas (IXa), (IXb) and (IXc) are alkyl groups, the number of carbon atoms is usually 1 to 15, preferably 1 to 5, alkenyl group, When it is an alkynyl group, the number of carbon atoms is usually 2 to 15,
Preferably 2 to 5, the substituent in these, an alkoxy group, a phenoxy group, hydroxy group, or a phenyl group, examples of the substituent in L ^1, an alkyl group, an amino group, a halogen atom, an aryl Examples include a mercapto group or a heteroaromatic mercapto group,
Examples of the substituent on the quinoline ring include an alkyl group, an alkoxy group, a nitro group, and a halogen atom.

As the indole-based and benzothiazole-based dye cations, those represented by the following formula (X) are particularly preferable.

[0100]

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[In the formula (X), Y ¹ and Y ² each independently represent a dialkylmethylene group or a sulfur atom, and R ³ and R ⁴ each independently may have a substituent. An alkyl group, an alkenyl group which may have a substituent, an alkynyl group which may have a substituent, or a phenyl group which may have a substituent, and L ² has a substituent Represents a tri, penta, hepta, nona, or undecamethine group which may be substituted, and two substituents on the penta, hepta, nona, or undecamethine group are connected to each other to have 4 carbon atoms.
To 7 may form a cycloalkene ring, a cycloalkeneone ring, a cycloalkenedione ring, or a cycloalkenethione ring, and the fused benzene ring may have a substituent. The substituents may be linked to each other to form a fused benzene ring. ]

Here, when R ³ and R ⁴ in the formula (X) are an alkyl group, the number of carbon atoms is usually 1 to 15, preferably 1 to 15.
When it is an alkenyl group or an alkynyl group, the number of carbon atoms is usually 2 to 15, preferably 2 to 5, and examples of the substituent include an alkoxy group, a phenoxy group, a hydroxy group, and a phenyl group. is, as the substituent in L ^2, an alkyl group, an amino group, an aryl mercapto group, such as heteroaromatic mercapto group or a halogen atom. Examples of the substituent in the benzene ring, an alkyl group, an alkoxy group, or a halogen atom And the like.

As the iminocyclohexadiene dye cation, those represented by the following general formula (XI) are particularly preferred.

[0104]

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[In the formula (XI), R ⁵ , R ⁶ , R ⁷ and R ⁸
Each independently represents an alkyl group; R ⁹ and R ¹⁰ each independently represent an aryl group, a furyl group, or a thienyl group which may have a substituent; and L ³ has a substituent. Represents a mono, tri, penta, or heptamethine group which may be substituted, and two substituents on the tri, penta, or heptamethine group are connected to each other to form a cycloalkene ring having 4 to 7 carbon atoms, a cycloalkene ring, A cycloalkenedione ring or a cycloalkenethione ring may be formed, and the quinone ring and the benzene ring may have a substituent. ]

Here, R ⁵ , R ⁶ , R ⁷ in formula (XI)
And when R ⁸ is an alkyl group, the number of carbon atoms is usually 1 to 1
5, preferably 1 to 5, and the carbon number when R ⁹ and R ¹⁰ are an aryl group is usually 6 to 20, preferably 6 to
15, specifically as R ⁹ and R ¹⁰ , a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-furyl group,
3-furyl, 2-thienyl, 3-thienyl group and the like, as those of the substituent groups include an alkyl group, an alkoxy group, a dialkylamino group, hydroxy group, or a halogen atom and the like, in the L ³ As the substituent,
Examples thereof include an alkyl group, an amino group, an arylmercapto group, a heteroaromatic mercapto group, and a halogen atom.

The pyrylium-based and thiapyrylium-based dye cations are particularly preferably represented by the following general formula (XII)
Those represented by a), (XIIb) or (XIIc) are preferred.

[0108]

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[In the formulas (XIIa), (XIIb) and (XIIc), Z ¹ and Z ² each independently represent an oxygen atom or a sulfur atom, and R ¹¹ , R ¹² , R ¹³ and R ¹⁴ Are each independently a hydrogen atom or an alkyl group, or R ¹¹ and R
¹³ , and R ¹² and R ¹⁴ may be linked to each other to form a cycloalkene ring having 5 or 6 carbon atoms, and L ⁴ may be mono, tri, penta, or heptamethine which may have a substituent. And the two substituents on the tri, penta, or heptamethine group are linked together to form a cycloalkene ring, cycloalkeneone ring, cycloalkenedione ring, or cycloalkenethione ring having 4 to 7 carbon atoms. And the pyrylium ring and the thiapyrylium ring may have a substituent. In this case, two adjacent substituents may be connected to each other to form a fused benzene ring. ]

Here, the formulas (XIIa), (XIIb),
And when R ¹¹ , R ¹² , R ¹³ and R ^{14 in} (XIIc) are an alkyl group, the number of carbon atoms is usually 1 to 15, preferably 1 to 5, and the substituent in L ⁴ is alkyl Examples include a group, an amino group, an arylmercapto group, a heteroaromatic mercapto group, and a halogen atom. Examples of the substituent on the pyrylium ring and the thiapyrylium ring include an aryl group such as a phenyl group and a naphthyl group.

The quinoline dye cations represented by formulas (IXa to IXc), the indole or benzothiazole dye cations represented by formula (X), and the cations represented by formula (XI) Iminocyclohexadiene-based dye cations, and the compounds represented by the general formulas (XIIa to XII)
Among the pyrylium-based or thiapyrylium-based dye cations represented by IIc), in the present invention, the indole-based or benzothiazole-based dye cations represented by the general formula (X) are particularly preferable. Specific examples of each of these cyanine dye cations are shown below. However, (VI-11) is an example in which an inner salt is formed.

[0112]

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[0113]

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[0114]

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[0115]

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[0116]

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[0117]

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[0118]

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[0119]

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[0120]

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[0121]

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The phthalocyanine sensitizing dyes include
It is preferably represented by the following general formula.

[0123]

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(In the formula (XIII), M is a hydrogen atom SnC
l ₂ , Zn, Cu, AlCl, or Ni, wherein the benzene ring has an alkoxy group, an alkylthioxy group, an aryloxy group, an arylthioxy group, a fluorine atom, a chlorine atom at each o-position or m-position. , A bromine atom, an iodine atom, an alkylamino group, or an arylamino group may be used as a substituent. Further, the phenyl ring may be such that two adjacent substituents are connected to each other to form a fused benzene ring. Here, in the formula (XIII), M is Zn or SnCl ₂
Are preferred as the benzene cyclic substituent, a C1-10 alkoxy group, a C1-10 alkylthioxy group, a C1-10
Aryloxy group, C1-10 arylthioxy group,
A fluorine atom, a chlorine atom and a bromine atom are preferred, and those having a substituent at the m-position of the benzene ring are particularly preferred because of their excellent solubility in organic solvents. Specific examples of the phthalocyanine sensitizing dye are shown below.

[0125]

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(C) Constituting the Photopolymerizable Composition of the Invention
The organic boron anion as the component is a radical generator that generates an active radical when irradiated with light in the presence of the cyanine sensitizing dye cation or the phthalocyanine sensitizing dye as the component (B). Sho 62-143 044
JP-A-62-150242, JP-A-9-1886
No. 85, JP-A-9-188686, JP-A-9-188
No. 710, Japanese Patent No. 2764769, etc., and
Kunz, Martin “Rad Tech'98.Proceeding April 19-22,1
998, Chicago "and the like.
Those represented by the following general formula (XIV) are preferred.

[0127]

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[In the formula (XIV), R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ are each independently an alkyl group which may have a substituent or an alkenyl which may have a substituent. A group, an alkynyl group which may have a substituent, an aryl group which may have a substituent, or a heterocyclic group, which may be linked to each other to form a cyclic structure; At least one of them is an alkyl group which may have a substituent. ]

Here, R ¹⁵ , R ¹⁶ , R in the formula (XIV)
^{When 17} and R ¹⁸ are alkyl groups, the number of carbon atoms is usually 1
-15, preferably 1-5, the number of carbon atoms when it is an alkenyl group or an alkynyl group is usually 2-15, preferably 2-
5, the number of carbon atoms when it is an aryl group is usually 6 to 20, preferably 6 to 15, and the number of carbon atoms when it is a heterocyclic group is usually 4 to 20, preferably 4 to 15. Represents a halogen atom, an alkyl group, an alkoxy group, a trifluoromethyl group, a trimethylsilyl group, or the like. Among them, it is preferred that R15 to R17 are independently a phenyl group optionally substituted with a halogen atom, and R18 is an alkyl group having 1 to 6 carbon atoms.

Specific examples of these organic boron anions include, for example, n-butyl-methyl-diphenyl boron anion, n-butyl-triphenyl boron anion and n-butyl-triphenyl boron anion.
-Butyl-tris (2,4,6-trimethylphenyl)
Boron anion, n-butyl-tris (p-methoxyphenyl) boron anion, n-butyl-tris (p-fluorophenyl) boron anion, n-butyl-tris (m-
Fluorophenyl) boron anion, n-butyl-tris (2,6-difluorophenyl) boron anion, n-butyl-tris (2,4,6-trifluorophenyl) boron anion, n-butyl-tris (2,3 , 4,5,6
-Pentafluorophenyl) boron anion, n-butyl-tris (p-chlorophenyl) boron anion, n-butyl-tris (trifluoromethyl) boron anion, n
-Butyl-tris (2,6-difluoro-3-pyrrolylphenyl) -boron anion;

In the present invention, in order for the cyanine dye cation of the component (B) and the organic boron anion of the component (C) to be present in the photopolymerizable composition, (a) the cyanine dye cation and the aforementioned A method of blending a salt with an organic boron anion, or (ii) a salt (including the case of an intramolecular salt) of the cyanine dye cation and an appropriately selected counter anion; It depends on the method of compounding a salt with a cation.

In order that the phthalocyanine-based sensitizing dye of the component (B) and the organic boron anion of the component (C) are present in the photopolymerizable composition, the phthalocyanine-based sensitizing dye and the organic boron anion may be used. And a salt of a counter cation appropriately selected.

Here, as the counter anion, for example, C
l^-, Br^-, I^-, ClO_Four ^-, PF₆ ^-And BF_Four ^-,
BCl_Four ^-Inorganic acid anions such as inorganic boron anions such as
Benzene sulfonic acid, p-toluene sulfonic acid, naphthale
Organic acid anions such as sulfonic acid and acetic acid.
it can.

When an inner salt is formed, the compounds represented by the above-mentioned general formulas (IXa to IXc), (X), (XI) and (X
By having a barbiturate anion group or a thiobarbiturate anion group represented by the following general formula (XV) as a substituent of the polymethine chain of L ¹ , L ² , L ³ and L ⁴ in IIa to XIIc) Those which form a salt are preferred.

[0135]

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[In the formula (XV), Z ³ represents an oxygen atom or a sulfur atom, and R ¹⁹ and R ²⁰ each independently represent a hydrogen atom,
An alkyl group which may have a substituent, an alkenyl group which may have a substituent, an alkoxy group which may have a substituent, or a phenyl group which may have a substituent . ]

Here, when R ¹⁹ and R ²⁰ in the formula (XV) are an alkyl group or an alkoxy group, the number of carbon atoms is usually from 1 to 1.
15, preferably 1 to 5, the number of carbon atoms when it is an alkenyl group is usually 2 to 15, preferably 2 to 5, but is preferably an alkyl group, and as the alkyl group, specifically, a methyl group , An ethyl group, a propyl group, or a butyl group.

When the component (B) is a cyanine-based sensitizing dye, the above-mentioned general formulas (IXa to IXc), (X), (XI) and (XIIa to XIIc) may be used as counter anions other than the organic boron anion. ), A squarate anion group or a thiosquarate anion group, a croconate anion group or a thiocroconate anion group represented by the following general formula (XVI) in the polymethine chain of L ¹ , L ² , L ³ and L ^4. Are preferred to form an inner salt.

[0139]

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[In the formula (XVI), Z ⁴ , Z ⁵ , Z ⁶ , Z ⁷ ,
And Z ⁸ each independently represent an oxygen atom or a sulfur atom. ]

Examples of the counter cation include onium compounds such as alkali metal cation, ammonium cation, phosphonium cation, sulfonium cation and iodonium cation, and pyrylium cation, thiapyrylium cation and indolium cation. However, an organic ammonium cation such as a tetraalkylammonium is preferable, and particularly a C1-6
The tetraalkylammonium cation of the alkyl group is preferred.

The proportion of the component (B) in the whole photosensitive layer is preferably 0.05 to 20% by weight, and more preferably 0.2 to 20% by weight.
More preferably, it is 10 to 10% by weight. When these components are less than the above ranges, the sensitivity tends to decrease as a photopolymerizable composition, and when the components exceed the above ranges, residues in unexposed areas tend to be easily generated during development.

In the present invention, the compound containing a halomethyl group as the component (C) is activated radically when irradiated with light in the presence of the cyanine sensitizing dye cation or the phthalocyanine sensitizing dye as the component (B). Wherein at least one mono-, di- or trihalogen-substituted methyl group is bonded to an s-triazine ring.
Triazine compounds are preferred, and are represented by the following general formula (XVII)
Is particularly preferable.

[0144]

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[In the formula (XVII), X represents a halogen atom, W represents an aryl group or a heterocyclic group which may have a substituent, and R ²¹ represents a hydrogen atom, a halogen atom, an alkyl group, or Represents an aryl group, and r is an integer of 0 to 2; ]

The s-triazine compounds include
Specifically, for example, 2-methyl-4,6-bis (trichloromethyl) -s-triazine, 2-n-propyl-
4,6-bis (trichloromethyl) -s-triazine,
2- (α, α, β-trichloroethyl) -4,6-bis (trichloromethyl) -s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p- Methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (3,4-epoxyphenyl) -4,6-bis (trichloromethyl)
-S-triazine, 2- (p-chlorophenyl) -4,
6-bis (trichloromethyl) -s-triazine, 2-
[1- (p-methoxyphenyl) -2,4-butadienyl] -4,6-bis (trichloromethyl) -s-triazine, 2-styryl-4,6-bis (trichloromethyl) -s-triazine, -(P-methoxystyryl)
-4,6-bis (trichloromethyl) -s-triazine, 2- (pi-propyloxystyryl) -4,6
-Bis (trichloromethyl) -s-triazine, 2-
(P-tolyl) -4,6-bis (trichloromethyl)-
s-triazine, 2- (4-methoxynaphthyl) -4,
6-bis (trichloromethyl) -s-triazine, 2-
Phenylthio-4,6-bis (trichloromethyl) -s
-Triazine, 2-benzylthio-4,6-bis (trichloromethyl) -s-triazine, 2-methyl-4,6
-Bis (tribromomethyl) -s-triazine, 2-methoxy-4,6-bis (tribromomethyl) -s-triazine and the like, among which 2-methyl-4,6-bis (trichloromethyl) -S-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (3 , 4-Epoxyphenyl) -4,6-bis (trichloromethyl)
-S-triazine, 2- [1- (p-methoxyphenyl) -2,4-butadienyl] -4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxystyryl) -4,6 -Bis (trichloromethyl) -s-triazine, 2- (pi-propyloxystyryl)-
4,6-bis (trichloromethyl) -s-triazine and the like are preferable because of excellent stability over time.

The proportion of the component (C) in the whole photosensitive layer is preferably 0.05 to 20% by weight, and more preferably 0.2 to 20% by weight.
More preferably, it is 10 to 10% by weight. When these components are less than the above ranges, the sensitivity tends to decrease as a photopolymerizable composition, and when the components exceed the above ranges, residues in unexposed areas tend to be easily generated during development.

In the photosensitive layer according to the present invention, in addition to the ethylenic compound and the photopolymerization initiation system, an organic binder may be further used as a binder for modifying the photosensitive layer and improving physical properties after photocuring. It preferably contains a molecular substance (hereinafter, referred to as “polymer binder”).

In this case, the polymer binder to be used can be selected according to the compatibility, the film forming property, the adhesiveness and the purpose of improvement.

As specific examples of the polymer binder, for example,
(Meth) acrylic acid, (meth) acrylic acid ester,
(Meth) acrylamide, maleic acid, (meth) acrylonitrile, styrene, vinyl acetate, vinylidene chloride,
Examples thereof include homo- or copolymers of maleimide and the like, polyethylene oxide, polyvinyl pyrrolidone, polyamide, polyurethane, polyester, polyether, polyethylene terephthalate, acetyl cellulose, and polyvinyl butyral. Among them, a homopolymer of (meth) acrylic acid ester or a copolymer containing at least one kind of (meth) acrylic acid ester and (meth) acrylic acid as a copolymer component is preferable. The preferred acid value of the polymer binder having a carboxyl group in the molecule is 10 to 250, and the preferred weight average molecular weight (hereinafter abbreviated as “Mw”) is 5,000 to 500,000.

It is desirable that these polymer binders have an unsaturated bond in the side chain, and in particular, the following general formula (XVII)
It preferably has at least one type of unsaturated bond represented by any one of Ia to XVIIIc).

[0152]

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(Wherein R ¹⁰ represents a hydrogen atom or a methyl group. R ^{11 to} R ¹⁵ each independently represent a hydrogen atom, a halogen atom, an amino group, a dialkylamino group, a carboxyl group, an alkoxycarbonyl group, Having a sulfo group, a nitro group, a cyano group, an alkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent An aryloxy group which may be substituted, an alkylamino group which may have a substituent, an arylamino group which may have a substituent, an alkylsulfonyl group which may have a substituent, or a substituent An arylsulfonyl group optionally having
Represents an oxygen atom, a sulfur atom, an imino group, or an alkylimino group. The substituent such as the alkyl group which may have a substituent is not particularly limited as long as the reactivity of the carbon-carbon double bond is not extremely reduced, but is usually a halogen atom, an alkyl group, a phenyl group. Group, a cyano group, a nitro group, an alkoxy group, an alkylthio group, a dialkylamino group, or the like.

Among them, those represented by the general formula (XVIIIa) include those in which R ¹⁰ is a hydrogen atom or a methyl group, and R ¹¹ and R ¹² are each independently a hydrogen atom, a lower alkyl group or an alkoxy group. , A dialkylamino group or a cyano group is more preferable, and a compound represented by the general formula (XVIII)
As those represented by b), R ¹¹ and R ¹² are each independently a hydrogen atom, a halogen atom, a lower alkyl group, a carboxyl group, an alkoxycarbonyl group or a cyano group, and R ¹³ is a hydrogen atom, a halogen atom , Lower alkyl group,
More preferably, a carboxyl group, an alkoxycarbonyl group, or a cyano group, and R14 and R15 each independently represent a hydrogen atom, a halogen atom, or a lower alkyl group, and those represented by the general formula (XVIIIc) ,
It is more preferred that R ¹¹ , R ¹² and R ¹³ are each independently a hydrogen atom, a halogen atom, a lower alkyl group, a carboxyl group, an alkoxycarbonyl group or a cyano group. In addition, from the easiness of the addition reaction of the carbon-carbon double bond in the general formulas (XVIIIa to XVIIIc), the general formula (X
In VIIIa), at least 2 of R ^{10 to} R ¹²
Are hydrogen atoms, and the compounds represented by the general formulas (XVIIIb) and (X
In VIIIc), at least two of R ^{11 to} R ¹³
Those having a hydrogen atom are particularly preferred.

The methods of synthesizing these compounds are roughly classified into the following two methods.

(Synthesis method 1) An inert organic solvent solution of a polymer binder having a carboxyl group in the molecule (for example, alcohol, ester, aromatic hydrocarbon, aliphatic hydrocarbon, etc.) A method of reacting an unsaturated compound having an epoxy group with an epoxy group under a reaction condition of about 80 to 120 ° C. for about 1 to 50 hours.

The ratio of the carboxyl group to be reacted with the unsaturated compound having an epoxy group is not particularly limited as long as the effect of the present invention can be achieved. It is preferably from 20 to 80 mol%, more preferably from 30 to 70 mol%. Within the above range, the developing property is good and the adhesive property is good.

The unsaturated epoxy group-containing compound used in the production of the ethylenic polymer binder having an unsaturated group in the side chain includes:
A compound having at least one addition-polymerizable unsaturated bond and an epoxy group in one molecule.

Examples of the unsaturated compound having an epoxy group include glycidyl (meth) acrylate, allyl glycidyl ether, α-ethyl glycidyl acrylate, crotonyl glycidyl ether, glycidyl crotonate, glycidyl isocrotonate, monoalkyl itaconate monoglycidyl ester And aliphatic epoxy group-containing unsaturated compounds such as monoalkyl fumarate monoglycidyl ester, monoalkyl maleate monoglycidyl ester, and the following structural formulas (XIXa) to (XIX).
IXn) and the alicyclic epoxy group-containing unsaturated compound.

[0160]

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[0161]

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(In each formula, R¹⁶, R¹⁷, R¹⁸Are independent
Represents a hydrogen atom or a methyl group. R ¹⁹, R²⁰, R^{twenty one}Is each
Each independently a divalent aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms
Is shown. R^{twenty two}, R^{twenty three}Are each independently 2 to 10 carbon atoms
Represents a monovalent hydrocarbon group. q and r each represent an integer of 0 to 10
You. ) The preferred compounds of the above epoxy group-containing unsaturated compounds
Examples of glycidyl methacrylate, allyl
Ricidyl ether, 3,4-epoxycyclohexylme
Tyl acrylate and the like. Especially good among these
Preferred compounds are allyl glycidyl ether and 3,4-E
Poxycyclohexylmethyl acrylate.

(Synthesis Method 2) The above general formula (XVIIIb)
And a compound having a total of two or more unsaturated bonds of at least one unsaturated bond having a low reactivity and at least one unsaturated bond having a higher reactivity as shown in (XVIIIc), and an unsaturated carboxylic acid. And synthesizing them by copolymerizing them.

Specific examples of the compound having an unsaturated group represented by the general formula (XVIIIb) include allyl (meth) acrylate, 3-allyloxyethyl (meth) acrylate, and 3-allyloxy-2-hydroxypropyl (meth) Acrylates, N, N-diallyl (meth) acrylamide, cinnamyl (meth) acrylate, crotonyl (meth) acrylate, methacryl (meth) acrylate and the like can be mentioned. Of these, allyl (meth) acrylate is particularly preferred.

Specific examples of the compound having an unsaturated group represented by the general formula (XVIIIc) include vinyl (meth) acrylate, vinyl crotonate, 1-propenyl (meth) acrylate, 1-chlorovinyl (meth) acrylate, 2-phenylvinyl (meth) acrylate, vinyl (meth) acrylamide, and the like. Of these, vinyl (meth) acrylate is particularly preferred.

By copolymerizing these monomers with an unsaturated carboxylic acid, preferably acrylic acid or methacrylic acid, a copolymer having the unsaturated group is obtained. As the monomer to be copolymerized, another monomer may be copolymerized in addition to the unsaturated carboxylic acid, and examples thereof include alkyl acrylate, alkyl methacrylate, acrylonitrile, and styrene. General formulas (XVIIIb), (X
The ratio of the compound having the structure VIIIc) to the total components of the polymer is preferably from 10 to 90 mol%, more preferably from 30 to 80 mol%. If it is less than this range, the sensitivity and printing durability are poor, and if it is too large, the image reproducibility deteriorates.

The mixing ratio of such a polymer binder is from 0 to 90% by weight, especially from 20 to 90% by weight, based on the total solid content of the photosensitive layer.
It is preferably 80% by weight, particularly preferably 30 to 70% by weight.

Next, the photopolymerizable composition used in the present invention preferably contains a coloring dye having an absorption maximum peak at 450 to 650 nm as the component (D) of the present invention. Specifically, coloring dyes such as a basic dye, a reactive dye, an acid dye, and a direct dye are exemplified. In the case of adding a coloring dye, a basic dye is particularly preferred from the viewpoint of the effect of the present invention that a decrease in sensitivity in laser exposure at 650 to 1200 nm is small, and among them, a triphenylmethane dye excellent in coloring property is more preferred. Specifically, the following general formula (D
A dye represented by -I).

[0169]

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(X in the formula (DI)^-Replaces the counter anion
And R_a1~ R_a6May be the same or different, water
Represents a hydrogen atom, an alkyl group or an aryl group, and a benzene ring
May have a substituent, in which case two adjacent
Are linked together to form a fused benzene ring
You may. p represents 0 or 1. Preferably, X^-Is Cl^-, Br^-, I^-, ClO_Four ^-, PF
₆ ^-, BF_Four ^-And BCl _Four ^-, Benzenesulfonic acid, palat
Ruenesulfonic acid, naphthalenesulfonic acid or acetic acid
Or R_a1~ R_a6May be the same or different
A C1-10 alkyl group, a hydrogen atom, a phenyl group,
Condensed Benze when benzene ring forms fused benzene ring
The ring is a naphthalene ring, and p is 0 or 1. this
Specific examples of (DI) are shown below.

[0171]

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[0172]

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As the coloring dye of the present invention other than the above-mentioned triphenylmethane dye, dyes exemplified as water-soluble dyes in JP-B-7-60268 can be mentioned.

The compounding ratio of the coloring dye having an absorption maximum at 450 to 650 nm of the component (D) is usually in the range of 1 to 20% by weight based on the entire photopolymerizable composition. It is preferably at least 1.5% by weight, more preferably at least 4% by weight, preferably at most 15% by weight, more preferably at most 12% by weight. If it is less than 1% by weight, the coloring is insufficient and the visibility is poor (clear colored images cannot be obtained after development). On the other hand, when the content exceeds 20% by weight, a remarkable decrease in sensitivity in laser exposure at 750 to 1200 nm is caused. In particular, when the amount is in the range of 1 to 3% by weight, more preferably 1.5 to 2.5% by weight, high sensitivity can be maintained, and on the other hand, the amount of addition is 4 to 15% by weight, more preferably 4 to 12%. When the content is in the range of% by weight, remarkable improvement in printing durability can be seen, so that it is preferable. Therefore, the amount of the coloring dye may be appropriately adjusted within the above range according to the purpose.

High concentration of colored dye added (4% by weight or more)
In this case, the print-developed photosensitive lithographic printing plate of the invention is considered to exhibit a characteristic effect by the mechanism described below.
800-1000nm near infrared laser beam 10μm
When scanning exposure is performed on a high-intensity laser spot condensed to a diameter of about 2 mm,
Since a high-temperature state of 00 to 1000 ° C. is formed, a multiphoton sensitization reaction is induced by high-density light absorption. It is considered that photopolymerization proceeds. Therefore, it is considered that a coloring dye having a large desensitizing effect can be blended at a high concentration in a general photopolymerization system. Furthermore, when a coloring dye having a highly basic chromophore is added at a high compounding ratio, a matrix structure due to hydrogen bonding or the like is formed between the carboxylic acid group of the organic polymer binder and the coloring dye in the photosensitive layer. It is considered that the film is formed to increase the film strength of the photocurable photosensitive layer and to exhibit high printing durability.

The photopolymerizable composition of the present invention may further comprise, if necessary, other components (F) other than (1) a photopolymerization initiator system containing the components (B) and (C). As a polymerization initiator component, a thiol compound, and an amine compound, (2)
Plasticizers such as dioctyl phthalate, didodecyl phthalate, tricresyl phosphate, dioctyl adipate, triethylene glycol dicaprylate, (3) hydroquinone, resorcinol, pyrogallol, p-methoxyphenol, 2,6-di-t-butyl- Thermal polymerization inhibitors such as p-cresol and β-naphthol may be added.

The photopolymerizable composition for forming the photosensitive layer may further contain, if necessary, other additives such as hydroquinone, p-methoxyphenol, and 2,6.
Thermal polymerization inhibitors such as -di-t-butyl-p-cresol, coloring agents comprising organic or inorganic dyes and pigments other than the component (D), dioctyl phthalate, didodecyl phthalate,
Plasticizers such as tricresyl phosphate, sensitivity improving agents such as tertiary amines and thiols, and other additives such as dye precursors may be added.

In this case, the preferable compounding amount of these various additives is such that the thermal polymerization inhibitor 2 based on the total solid content of the photosensitive layer.
% By weight, colorants such as dyes and pigments, 40% by weight or less, plasticizers, 10% by weight or less, sensitivity characteristic improvers, 20% by weight or less,
The content of the dye precursor is 30% by weight or less.

The photopolymerizable composition of the present invention is usually prepared by applying a solution prepared by dissolving the above-mentioned components in an appropriate solvent onto the surface of a hydrophilic support by a known coating method, followed by drying to obtain a photosensitive layer. To form a lithographic printing plate.

Here, the solvent is not particularly limited as long as it has a sufficient solubility for the components used and gives good coating properties. Examples of the solvent include methyl cellosolve,
Cellosolve solvents such as ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate , Propylene glycol solvents such as dipropylene glycol dimethyl ether, butyl acetate, amyl acetate, ethyl butyrate, butyl butyrate, diethyl oxalate, ethyl pyruvate, ethyl-2-hydroxybutyrate, ethyl acetoacetate, methyl lactate, ethyl lactate, Ester solvents such as methyl 3-methoxypropionate, heptanol Hexanol, diacetone alcohol, alcohol solvents such as furfuryl alcohol, cyclohexanone, ketone solvents such as methyl amyl ketone,
Highly polar solvents such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone and the like, or a mixed solvent thereof, and further a mixture thereof with an aromatic hydrocarbon may be used. The usage ratio of the solvent is usually in the range of about 1 to 20 times by weight based on the total amount of the photopolymerizable composition.

As the coating method, conventionally known methods, for example, spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, curtain coating and the like can be used. The amount of application varies depending on the application, but usually 3 to 70 mg as a dry film thickness.
/ Dm ^2, preferably from 5 to 50 mg / dm ^2, particularly preferably in the range of 10 to 30 mg / dm ^2. The drying temperature at that time is, for example, about 60 to 170 ° C., preferably about 70 to 150 ° C., and the drying time is, for example, about 5 seconds to 10 minutes, preferably about 10 seconds to 5 minutes. Can be

Incidentally, an oxygen barrier layer containing polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene oxide, cellulose or the like is usually provided on the photopolymerizable layer (photosensitive layer) in order to prevent polymerization inhibition by oxygen. Provided.

Next, a method of making a printing plate using the photosensitive lithographic printing plate of the present invention will be described. In order to form an image using the photosensitive lithographic printing plate of the present invention, the printing plate is 750
After exposure with a near-infrared laser having an oscillation wavelength of １1200 nm, preferably with a light intensity of 10 ³ W / cm ² or more, printing and development are performed to remove unexposed portions. The photopolymerizable composition of the present invention has a visible image with exposure while maintaining high sensitivity by exposure at a high exposure intensity density using a laser having an oscillation wavelength of 750 to 1200 nm, and is handled under a white lamp. Also excellent in nature.

The exposure light source applicable to the composition of the present invention is not particularly limited as long as it has a laser having an oscillation wavelength of 750 to 1200 nm.
It is a laser having an oscillation wavelength between 850 nm and 900-1100 nm. The exposure is performed by using a laser beam having a laser output light intensity of 0.1 to 100 W, preferably 0.5 to 70 W, as a beam spot having a diameter of 2 to 30 μm, preferably 4 to 20 μm, and 0.1 to 500 m / s, preferably 0 to 500 μm. This is performed by moving the beam spot at a scanning speed of 3 to 400 m / s. Laser light exposure on the image forming material, 200 mJ / cm ² or less, preferably imagewise exposed so that 150 mJ / cm ² or less. The lower limit is preferably as small as possible, but usually 1 mJ /
cm ² or more.

The image-exposed photosensitive lithographic printing plate can be used as it is for mounting on a plate cylinder of a printing press for printing. The unexposed portion of the photosensitive layer having low adhesiveness is peeled off and transferred to the roller surface side of the blanket rubber roller (impression cylinder) together with the printing ink. The photosensitive layer transferred to the blanket rubber roller is transferred to printing paper together with the ink, and the printing paper in the initial stage of printing becomes waste paper, thereby achieving print development. As a result, the hydrophilic surface of the support in the portion is exposed, and an image-like ink image composed of the printing ink water and the ink balance is formed on the plate surface.
The ink image is transferred to a blanket roller and then to printing paper, and printing is performed.

[0186]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof. In the following, “%” indicates “% by weight” unless otherwise specified.

The following examples and comparative examples used:
The hydrophilic support, the ethylenic compound and the polymer binder are as follows.

(Hydrophilic support-1) An aluminum plate having a thickness of 0.2 mm was degreased with 3% sodium hydroxide.
In a 8.0 g / L nitric acid bath, electrolytic etching was performed at 25 ° C. and a current density of 80 A / dm ² for 15 seconds, followed by desmutting with a 1% aqueous sodium hydroxide solution at 50 ° C. for 5 seconds.
Next, the mixture was neutralized with a 10% aqueous solution of nitric acid at 25 ° C. for 5 seconds. After washing with water, 30% sulfuric acid bath at 30 ° C and 10 A / dm ² conditions.
Anodized for 2 seconds, washed with water and dried to obtain an aluminum plate for lithographic printing plate ("Support 1"). The formed anodized film is 2.1 g / m ² .

(Hydrophilic support-2) Support-1 was further treated with an aqueous 1% sodium orthosilicate solution at 85 ° C for 30 minutes.
After hydrophilization for 2 seconds, washing with water and drying, an aluminum plate for a lithographic printing plate ("Support 2") was obtained.

(Hydrophilic support-3) An aluminum plate for a lithographic printing plate ("support-3") was obtained in the same manner as in the production of support-1, except that phosphoric acid was used instead of sulfuric acid. Was. The formed anodized film is 1.8 g / m ² .

(Hydrophilic support-4) Water development type negative type lithographic printing plate manufactured by AGF: A photosensitive layer of HYDROPRINT was removed by washing with water to obtain a polyethylene terephthalate support for lithographic printing plate ("Support-4"). Was. This polyethylene terephthalate support has a roughened thickness of 180.
This is one in which a hydrophilic polymer layer of several μm is formed on a polyethylene terephthalate of μm.

(Hydrophilic support-5) On the aluminum plate treated in the same manner as the support-1 except that electrolytic etching was carried out using hydrochloric acid instead of nitric acid, 50 pp.
It was immersed in an mCMC aqueous solution for 5 seconds to obtain an aluminum plate for a lithographic printing plate ("Support-5").

(Ethylenic compound-1) Nippon Kayaku Co., Ltd.
"PM-2" (structural formula is as follows) (ethylenic compound-2) "UA-" manufactured by Shin-Nakamura Chemical Co., Ltd.
306H "(the structural formula is as follows) (Ethylene compound-3)" ABP "manufactured by Shin-Nakamura Chemical Co., Ltd.
E-4 "(The structural formula is as follows.) (Ethylenic compound-4) Ethylenic compound of the following structural formula

[0194]

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(Polymer Binder-1) Methyl methacrylate / isobutyl methacrylate / isobutyl acrylate / methacrylic acid = 35/20/10/35 mol% (charge ratio) (Mw 70,000)

(Polymer Binder-2) 3-allyloxy-2-hydroxypropyl methacrylate 80 was placed in a 3 L four-necked flask equipped with a stir bar equipped with blades, reflux cooling, and a nitrogen tube.
g, 20 g of methacrylic acid and 1.6 L of ethanol as a reaction solvent were added, and heated and stirred in a 90 ° C. oil bath.
1.6 g of azobisisobutyronitrile was added to this solution for 40 minutes.
It was dissolved in 0 mL of ethanol and added. After heating and stirring for 3 hours, the nitrogen tube was removed, and p-methoxyphenol 0.0
4 g and 400 mL of propylene glycol monomethyl ether acetate were added, the bath temperature was raised to 100 ° C., and the heating and stirring were continued for 1 hour. Finally, ethanol was distilled off to remove 18 of ethylenic polymer binder-2 (Mw 300,000).
% Solution was obtained.

(Polymer binder-3) 107 g of allyl methacrylate, 13 g of methacrylic acid, and 1.6 L of ethanol as a reaction solvent were placed in a 3 L four-necked flask equipped with a stir bar equipped with blades, reflux cooling, and a nitrogen tube. The mixture was heated and stirred in a 90 ° C. oil bath. 1.6 g of azobisisobutyronitrile dissolved in 400 mL of ethanol was added to this solution. After heating and stirring for 3 hours, the nitrogen tube was removed, 0.04 g of p-methoxyphenol and 400 mL of propylene glycol monomethyl ether acetate were added, the bath temperature was raised to 100 ° C, and heating and stirring were continued for 1 hour. Finally, ethanol is distilled off to remove the ethylenic polymer binder-3.
A 20% solution of (Mw 180,000) was obtained.

(Polymer binder-4) The above-mentioned polymer binder-
1,200 parts by weight, the following alicyclic epoxy-containing unsaturated compound: 75 parts by weight, p-methoxyphenol: 2.5 parts by weight,
8 parts by weight of tetrabutylammonium chloride and 800 parts by weight of propylene glycol monomethyl ether acetate are added to a reaction vessel, and the mixture is stirred and reacted in air at 110 ° C. for 24 hours to produce an ethylenic polymer molecule binder-4 (Mw).
75,000, an acid value of 60, and 60% of the entire methacrylic acid component of the polymer binder-1 reacted with an unsaturated group. ) Of 25
% Solution was obtained.

[0199]

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(Examples 1 to 6, Comparative Example 1)
A coating solution of the photopolymerizable composition was prepared by using a bar coater so as to have a dry film thickness of 2 g / m2.
And dried. Further, an aqueous solution of polyvinyl alcohol was applied thereon using a bar coater and dried to a thickness of 3 μm at a dry film weight of 3 g / m 2 and dried.
A photosensitive lithographic printing plate was prepared. The following items were evaluated for the obtained photosensitive lithographic printing plate, and the results are shown in Table 1.

[0201]

[Table 1] Photopolymerizable composition coating solution formulation-1 (parts by weight) Ethylenic monomer shown in Table 1: 55 Polymer binder shown in Table 1: 45 Compound of the following structural formula (A-1): 2.0 Compound of the following structural formula (B-1): 5.0 N, N-dimethylbenzoic acid ethyl ester: 10 Ethyl violet: 5.0 Cyclohexanone: 1090

[0202]

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(Peel strength) The peel strength of the gum tape of the hydrophilic support was measured according to the following measuring method. As shown in FIG. 1 (a), the peel strength (hereinafter, referred to as "gum tape peel strength") of the support subjected to the hydrophilic treatment (hereinafter, referred to as "hydrophilic support") by a gum tape showing surface adhesiveness is as shown in FIG. Gum tape (SLIONTEC SL)
ION TAPE) 3 at 25 ° C., 5 kg / cm ² , 50
After pressure bonding at a rate of 1 cm / min, the support 1 is fixed on the fixing table 2, and the force required when pulling the gum tape 3 so that the gum tape 3 and the support 1 are separated from each other in the direction of 180 ° at 30 cm per minute. F divided by the width of the packing tape (g)
/ Cm).

(Sensitivity) The photosensitive lithographic printing plate was image-exposed at various exposure amounts using a near-infrared exposure apparatus (Trendsetter 3224-T: oscillation wavelength: 830 nm) manufactured by Creo Co., Ltd. Attached to the plate cylinder on a lithographic printing machine “Diamond F-2] manufactured by Mitsubishi Heavy Industries, Ltd.
o.1 Mark II), printing was performed by printing 100 sheets using printing ink (Toyo Process Ink High Echo Magenta). The sensitivity was evaluated based on the minimum laser exposure amount (energy) at which a printed image on the 100th printed material obtained appeared. F in the table indicates that no image was formed even at an exposure amount of 1000 mJ / cm ² . The results are shown in Table 1.

[0205]

[Table 2]

Example 7 The sensitivity was evaluated in the same manner as in Example 1 except that the photosensitive layer having the following composition-2 was used and the support -5 was used. The sensitivity was 100 mJ / cm ² . The peel strength of the support 5 was 300 g.

[0207]

Table 3 Formulation of photopolymerizable composition coating liquid-2 (parts by weight) Dipentaerythritol hexaacrylate: 50 Acrylate urethane oligomer (Ebecryl 8301 manufactured by Radcare): 10 Polymethyl methacrylate (Mw = 30000): 40 The above structural formula Compound of (A-1) 2.0 Compound of the above structural formula (B-1): 5.0 Ethyl violet: 5.0 Cyclohexanone: 1090 Methyl cellosolve: 100

Example 8 In Example 7, 0.1% by weight of polyvinyl alcohol GL-03 manufactured by Nippon Synthetic Chemical Co., Ltd.
After coating with a wire bar of 0.5 and drying at 70 ° C. for 2 minutes to form a release layer, the following structural formula (A-2) is used instead of the compound of structural formula (A-1), The sensitivity was evaluated in the same manner as in Example 7, except that the following structural formula (B-2) was used instead of the compound (B-1). Sensitivity is 150
mJ / cm ² .

[0209]

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Example 9 The sensitivity was evaluated in the same manner as in Example 7, except that the cover sheet layer of polyvinyl alcohol was not provided. The sensitivity was 200 mJ / cm ² .

Example 10 The sensitivity was evaluated in the same manner as in Example 7, except that ethyl violet was not used. The sensitivity was 70 mJ / cm ² .

Reference Example 1 A 0.24 mm thick aluminum plate was degreased on its surface in a 5% by weight aqueous sodium hydroxide solution at 60 ° C. for 1 minute, and then a 0.5 mol / liter aqueous hydrochloric acid solution was used. After performing an electrolytic etching treatment at 28 ° C. and a current density of 60 A / dm ² for 40 seconds, and then performing a desmut treatment at 60 ° C. for 12 seconds in a 4% by weight aqueous sodium hydroxide solution,
In a 20% by weight aqueous sulfuric acid solution, 20 ° C., 3.5 A / dm ²
At a current density of 1 minute, sealed with hot water at 80 ° C. for 20 seconds, washed with water and dried to prepare a support for a photopolymerizable lithographic printing plate. Next, the following photosensitive composition solution (formulation-
The coating solution prepared by stirring 3) at room temperature for 10 minutes was applied using a wire bar, dried at 80 ° C. for 2 minutes to form a photopolymerizable composition layer having a thickness of 20 mg / dm ² , and An aqueous solution composed of polyvinyl alcohol: polyvinylpyrrolidone (95: 5 weight ratio) is applied thereon, dried at 80 ° C. for 2 minutes to form an overcoat layer having a thickness of 30 mg / dm ² , and photopolymerizable lithographic printing. A plate was made.

Photopolymerizable Composition Coating Solution Formulation-3 Ethylene Monomer 1 22 parts by weight of UA-306H Ethylene Monomer 2 22 parts by weight of ABPE-4 22 parts by weight of Ethylene Monomer 3 11 parts by weight of PM-2 Sensitizing dye: 5 parts by weight of the compound (A-2) Radical generator: 5 parts by weight of the compound (B-2) Coloring dye: 5 parts by weight of ethyl violet 50 parts by weight of a polymer binder (polymer binder-5 having the following composition) Cyclohexane 500 parts by weight Methyl cellosolve 500 parts by weight

[0214]

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The photopolymerizable lithographic printing plate thus obtained was subjected to 400 lux (6.2 × 10 −5 W) of a white fluorescent lamp (36 W white fluorescent lamp manufactured by Mitsubishi Electric Corporation “Neorumi Super FLR40S-W / M / 36”). / Cm2: This is the light intensity at a relative luminosity factor of 1 at 550 nm described in "Optics", written by Kozo Ishiguro, published by Kyoritsu Shuppan Co., Ltd., p269 (1972), 1 lux = 1.55 × 10 ^-7 W / Cm ^2. ) After leaving for 10 minutes under irradiation of lux light intensity, the same print development treatment as described above was performed without laser exposure, whereby the composition layer was completely removed. . This indicates that the photosensitivity to a white fluorescent lamp is low.

Reference Example 2 A photosensitive lithographic printing plate was prepared in the same manner as in Reference Example 1 except that ethyl violet was not added to the photosensitive composition, and was left under a white fluorescent lamp for 10 minutes. did.
Next, when the same printing and developing treatment was performed without laser exposure, the composition layer was completely removed. This indicates that the photosensitivity to a white fluorescent lamp is low.

Reference Example 3 In Reference Example 1, the sensitizing dye represented by the structural formula (A-2)
Reference Example 1 except that 1 part by weight of the following structural formula (A-3) was used instead of the compound of formula (A-3), and 2 parts by weight of the following structural formula (B-3) was used instead of the compound of formula (B-2). A lithographic printing plate was prepared in the same manner as described above.

[0218]

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Next, a xenon lamp (“UI-501” manufactured by Ushio Inc.) was used using a spectral sensitivity measurement device (manufactured by Narumi).
Exposure was performed by irradiating the dispersed light with the light source “C” as the light source for 10 seconds while setting the exposure wavelength to change linearly in the horizontal axis direction and logarithmically changing the exposure intensity in the vertical axis direction. Print development was performed in the same manner as in Example 1, and from the obtained image,
The minimum exposure required for image formation at 532 nm was determined. The smaller the minimum exposure, the higher the sensitivity. From the above evaluation, the minimum exposure amount was 1200 μJ / cm.
^-2 indicated.

Reference Example 4 A photosensitive lithographic printing plate was prepared in the same manner as in Reference Example 3 except that ethyl violet was not added to the photosensitive composition, and exposed to a xenon lamp for 10 seconds. Next, print development processing was performed in the same manner as in Example 1, and the minimum exposure required for image formation at 532 nm was determined from the obtained image. The minimum exposure was 160 μJ /
cm ^-2 . That is, according to Reference Examples 3 and 4, 532n
It was shown that the sensitivity of the photopolymerizable composition capable of forming an image with a laser of m significantly changed depending on the presence or absence of the coloring dye. Further, when the composition was left under a white fluorescent lamp as in Reference Example 10 for 10 minutes and subjected to print development processing without laser exposure, the composition was completely photosensitive-cured and the composition layer was not removed at all. .

[0221]

According to the present invention, it has a high sensitivity to light in the near-infrared region, has excellent stability over time, and has excellent handleability under a white fluorescent lamp. A photopolymerizable lithographic printing plate and a plate making method thereof can be provided.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a method for measuring a gum tape peel strength.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support body 2 Fixed base 3 Adhesive tape

Continued on front page F term (reference) 2H025 AA13 AA14 AB03 AC08 AD01 BC13 BC42 CA14 CA41 CA42 CC11 DA36 FA10 2H084 AA14 AA32 AE05 BB04 CC05 2H096 AA06 BA05 EA04 EA23 2H114 AA04 AA22 AA23 DA04 DA09 DA28 GA05

Claims (7)

[Claims] (A) an ethylenic compound; (B) a cyanine sensitizing dye cation and / or a phthalocyanine sensitizing dye having a structure in which a heterocyclic ring is bonded via a polymethine chain;
(C) A photopolymerizable lithographic printing plate for print-developing near-infrared laser exposure, wherein a photosensitive layer containing an organic boron anion and / or a halomethyl group-containing compound is provided on a support subjected to hydrophilic treatment. A photopolymerizable lithographic printing plate for near infrared laser exposure for print development, wherein the peel strength of the gum tape from the support subjected to the hydrophilic treatment, determined by a peel strength measurement method using a gum tape, is 500 g / cm or less. . 2. The photopolymerizable lithographic printing plate according to claim 1, wherein the cyanine sensitizing dye cation and the phthalocyanine sensitizing dye have a maximum absorption at 750 to 1200 nm. 3. The photosensitive layer further comprises (D) 450 to 650 nm.
The photopolymerizable lithographic printing plate according to claim 1, further comprising 1 to 20% of a coloring dye having a maximum absorption. 4. The photopolymerizable lithographic printing plate according to claim 3, wherein the coloring dye is a basic dye. 5. The photopolymerizable lithographic printing plate according to claim 3, wherein the coloring dye is a triphenylmethane dye. 6. The photosensitive layer has a thickness of 800 to 850 nm or 90.
The photopolymerizable lithographic printing plate according to any one of claims 1 to 5, wherein a minimum exposure amount capable of forming an image with a laser having an oscillation wavelength of 0 to 1100 nm is 200 mJ / m ² or less. 7. The photosensitive layer of the photopolymerizable lithographic printing plate for print-developing near-infrared laser exposure according to any one of claims 1 to 6, which is image-wise exposed by near-infrared light. A method for forming a photo-cured photosensitive image by photo-curing a photosensitive layer and then removing an unexposed portion of the photosensitive layer from a support, comprising: When the ink is transferred to the roller surface of a blanket roller by supplying dampening water and printing ink onto the photosensitive layer of the photopolymerizable lithographic printing plate, A plate-making method for a photopolymerizable lithographic printing plate for print-developing near-infrared laser exposure, wherein the unexposed portion is removed from the support by transferring to a roller surface of a blanket roller using the adhesiveness of the plate. .