JP6487262B2 - Printing plate laminate for laser engraving - Google Patents

Description

  The present invention relates to a printing plate laminate for laser engraving.

2. Description of the Related Art Conventionally, as a printing plate using a photosensitive resin as a material, there is known a printing plate having a printing relief made of a cured photosensitive resin on a support.
Such a printing plate is widely used because a cured relief can be formed in a short time by an exposure process by irradiation with actinic rays and a development process in which unexposed areas are washed away with a chemical solution.

Among these, photosensitive resin relief plates using a metal material as a support are used as general printing plate materials, dry offset plate materials, metal foil printing plate materials, master plate-making plate materials, and embossing plate materials.
Photosensitive resin relief printing using such a metal material as a support is advantageous in that it does not impair the dimensional stability due to the elongation of the support in the mechanical attachment to the printing cylinder, and the printing machine cylinder using a magnet. It has the advantage that it can be mounted.

In the photosensitive resin relief printing plate as described above, it is required that the printing relief layer is firmly held on the support during use at the printing site. Therefore, it is a common practice to provide an adhesive layer in order to ensure the adhesive force between the support and the photosensitive resin layer.
The adhesive layer needs to satisfy both the adhesion at the interface between the adhesive layer and the metal support and the adhesion at the interface between the adhesive layer and the photosensitive resin layer. It is also necessary to have durability against chemicals used in the plate-making process, printing ink, and a cleaning solution for washing away the ink on the plate surface after printing.

The printing relief of the photosensitive resin letterpress suitable for the above-described applications is required to have a good developability and a relatively high hardness relief.
For example, from the viewpoint of enabling the use of an aqueous solution as a developer, a technique using a saponified polyvinyl acetate resin as a printing relief material (for example, see Patent Document 1), a technique using a water-soluble amide resin (for example, Patent Document 2) discloses a technique (for example, see Patent Document 3) in which a thermoplastic elastomer is used as a constituent for developing with an organic solvent. In these, a metal support is disclosed. A technique for ensuring the adhesion of the resin is disclosed.

  Specifically, Patent Document 1 discloses a saponification degree of 40 in order to adhere a photosensitive resin composition mainly composed of partially saponified polyvinyl acetate having a saponification degree of 60 to 90 mol% to a metal support. After applying a photosensitive adhesive mainly composed of 100 mol% partially saponified polyvinyl acetate to a metal support, the solvent is dried at 120 ° C. for 2 minutes, and further exposed to ultraviolet rays to form an adhesive layer A method of manufacturing is disclosed.

  Patent Document 2 discloses an epoxy-based, isocyanate-based, polyurethane-based adhesive or the like for bonding a photosensitive resin composition mainly composed of alcohol-soluble or water-soluble polyamide, polyvinyl alcohol SBR to a metal support. A method is disclosed in which an adhesive layer is produced by applying an adhesive to a metal support, followed by curing at 150 ° C. for 3 minutes.

  Further, Patent Document 3 discloses that a material capable of forming a crosslinked polymer matrix and an elastomeric binder (SBS block co-polymer) are used to adhere a photosensitive resin composition mainly composed of a thermoplastic elastomer binder to a metal support. A method of producing an adhesive layer by applying a mixture with a polymer, polyvinyl alcohol) to a metal support and heating at 170 to 180 ° C. for 2 to 2.5 minutes is disclosed.

On the other hand, in recent years, as a technique for simplifying the plate making process of a photosensitive resin printing plate, the resin is removed by irradiating the cured photosensitive resin obtained by curing the photosensitive resin composition layer with a laser beam to provide a printing relief. A method for forming the film (hereinafter sometimes referred to as laser engraving) is widely used.
For example, Patent Document 4 discloses a resin composition containing a photosensitive resin that is easily decomposed by laser light irradiation and an inorganic porous material for absorbing and removing generated liquid residue.

The applicant has already proposed several techniques regarding the technique for forming a printed relief by irradiating the cured photosensitive resin with a laser beam.
For example, Patent Document 4 discloses a photoengraving photomask for a printing original plate that includes a resin that is a plastomer at 20 ° C. containing a polymerizable unsaturated group, an organic compound having a polymerizable unsaturated group, and an inorganic porous material. A functional resin composition is disclosed.

  Patent Document 5 discloses a technique using a moisture-curable adhesive as a technique for forming a photosensitive resin composition mainly composed of an unsaturated urethane prepolymer having excellent laser engraving properties on a metal support. ing.

Further, Patent Document 6 discloses a technique using a urethane photosensitive resin made of unsaturated polyester.
In Patent Document 6, a photosensitive resin mainly composed of an unsaturated polyester urethane prepolymer composed of an unsaturated polyester resin, hexamethylene diisocyanate and hydroxypropyl methacrylate is applied on a metal support, and then a metal halide lamp is used. A resin cured layer is formed by irradiating light, and a photosensitive resin composition mainly composed of an unsaturated urethane prepolymer excellent in laser engraving property is applied to the upper layer portion, and photocured to obtain a laminate for a printing plate. Technology is disclosed.

Furthermore, Patent Document 7 discloses a technique using an adhesive having a three-layer structure as an adhesive for adhering a photosensitive resin composition containing an unsaturated polyurethane prepolymer as a main component to a support. Yes.
Patent Document 7 includes a first layer made of a polyester resin, a second layer made of an acrylic resin or a cellulose resin, and an adhesive composition comprising a vinyl chloride copolymer and a photopolymerization initiator as components. A technique relating to an adhesive material laminated on a substrate in three layers and in that order is disclosed.

Moreover, although it is not the thing of the applicant of this invention, the technique using the mixture of vinyl chloride-type resin and nitrile rubber is disclosed (for example, refer patent document 8).
Patent Document 8 includes a predetermined ratio of a vinyl chloride resin having an average degree of polymerization of 250 to 850 and a vinyl chloride content of 60 to 91% by weight and a nitrile rubber having an acrylonitrile content of 18 to 53% by weight. Techniques relating to adhesives are disclosed.

JP 59-172644 A JP 09-138507 A JP-T-2004-507778 International Publication No. 2003/022594 Pamphlet JP 2007-62201 A JP 2008-94030 A Japanese Patent Laid-Open No. 05-313377 Japanese Patent Laid-Open No. 06-342213

  However, in the prior art including the above-mentioned Patent Documents 1 to 3 and the like, there is still room for improvement in terms of stably exhibiting good adhesive strength when the photosensitive resin relief plate is used. In this regard, the techniques relating to Patent Documents 4 to 7 previously provided by the applicant can be expected to improve, but the applicant is conducting further research.

For example, in the technique disclosed in Patent Document 4, an unsaturated polyurethane system in which the end of a urethane compound obtained by polyaddition reaction of a polyol compound and a polyisocyanate compound is modified with a methacryl group as a material for forming a printing relief A prepolymer or the like is preferably used, but it is desirable if the adhesive strength can be further improved.
In this regard, for example, the adhesives disclosed in Patent Documents 1 to 3 and the like include a part of the photosensitive resin composition or a component that is chemically structurally similar to the adhesive resin composition. However, when a photosensitive resin composition mainly composed of an unsaturated polyurethane prepolymer is used, it is not always effective.

In the technique disclosed in Patent Document 5, a certain degree of improvement can be expected with respect to adhesive strength, but there are restrictions on the curing conditions (for example, curing temperature, curing humidity, curing time, etc.) of the moisture curable resin. Have the problem that there is.
In addition, when the adhesive is cured, it must be exposed in a short time from the application of a photosensitive resin composition mainly composed of an unsaturated urethane prepolymer with excellent laser engraving properties. There is also a problem that there is.
Furthermore, when using a sheet of a photosensitive resin laminate for a printing plate of a metal support in a desired printing machine, it is necessary to cut it into a predetermined size using a cutter or the like. There is also a problem that stronger adhesive strength may be required in order to suppress peeling of the end face of the laminate.

  Furthermore, in the technique disclosed in Patent Document 6, there is room for further improvement in the adhesive strength between the cured product of urethane photosensitive resin containing unsaturated polyester and the like and the laser engraving layer.

Furthermore, the technique disclosed in Patent Document 7 relates to a technique using a film of polyethylene terephthalate, polypropylene, triacetate resin, polystyrene or the like as a support, and further improves the adhesive strength of the adhesive to the metal support. Is desired.
The technique disclosed in Patent Document 8 is also desired to further improve the adhesive strength of the adhesive to the metal support.

  As described above, excellent adhesive strength can be stably exhibited with respect to the photosensitive resin relief plate in which the printing relief is formed on the metal support using the photosensitive resin composition mainly composed of unsaturated polyurethane prepolymer or the like. Further improvements are desired for photosensitive resin relief plates, particularly sheet-like photosensitive resin relief plates.

  In view of the above-described circumstances, an object of the present invention is to provide a printing plate laminate for laser engraving that can stably exhibit excellent adhesive strength.

As a result of intensive studies to solve such problems, the present inventor has found that the above problems can be solved by using an adhesive composition containing a thermosetting resin and a polyvinyl resin, and It came to be completed.
That is, the present invention is as follows.

[1]
A metal support;
An adhesive layer laminated on the surface of the metal support;
A photosensitive layer for printing relief laminated on the surface of the adhesive layer;
And having
The adhesive layer is a cured product made of a composition containing a thermosetting resin,
The photosensitive layer for printing relief includes an unsaturated polyurethane prepolymer, an ethylenically unsaturated compound, and a photopolymerization initiator,
A printing plate laminate for laser engraving in which the photosensitive layer for printing relief is cured.
[2]
The printing plate laminate for laser engraving according to [1], wherein the thermosetting resin is an epoxy resin or a urethane resin.
[3]
The printing plate laminate for laser engraving according to [1] or [2], wherein the thermosetting resin contains an amino resin.
[4]
The unsaturated polyurethane prepolymer according to any one of [1] to [3], wherein the unsaturated polyurethane prepolymer includes a polyester polyol and / or a polycarbonate polyol as a polymerization monomer and has a number average molecular weight of 1,000 to 100,000. Printing plate laminate for laser engraving.

  ADVANTAGE OF THE INVENTION According to this invention, the printing plate laminated body for laser engraving which can exhibit the outstanding adhesive strength stably can be provided.

Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as “the present embodiment”) will be described in detail.
The present invention is not limited to the present embodiment described below, and can be implemented with various modifications within the scope of the gist.
In the present specification, unless otherwise specified, “(meth) acryl” means “acryl” and / or “methacryl”, and similarly, “(meth) acryloyl” means “acryloyl” and / or “ “Methacryloyl”, “(meth) acrylate” is a concept meaning “acrylate” and / or “methacrylate”.

[Printed plate laminate for laser engraving]
The printing plate laminate for laser engraving of this embodiment is
A metal support;
An adhesive layer laminated on the surface of the metal support;
A photosensitive layer for printing relief laminated on the surface of the adhesive layer;
And having
The adhesive layer is a cured product made of a composition containing a thermosetting resin,
The photosensitive layer for printing relief includes an unsaturated polyurethane prepolymer, an ethylenically unsaturated compound, and a photopolymerization initiator,
It is a printing plate laminate for laser engraving in which the photosensitive layer for printing relief is cured.

(Metal support)
Examples of the material for the metal support include, but are not limited to, iron, aluminum, zinc, magnesium, nickel, chromium, copper, and various metal alloys.
Among these, iron having excellent rigidity is preferable from the viewpoint of dimensional stability.
In addition, the iron surface plated with tin, chromium, etc., the iron surface treated with chromium hydrated oxide, etc., or ferromagnetic materials (various iron powders, etc.) can be suitably used. It is.
Furthermore, tin-free steel (TFS), which is an electrolytic chromate-treated steel sheet, has good compatibility with the adhesive layer described later, and is bonded to a resin, that is, a photosensitive layer for printing relief formed on the adhesive layer. This is preferable because of improved properties.

  From the viewpoint of maintaining practical strength and enabling the laser engraving printing plate laminate of this embodiment to be wound around a cylindrical printing plate cylinder, the metal support has a thickness of 0.05 to The range is preferably 0.5 mm, more preferably 0.05 to 0.4 mm, and still more preferably 0.1 to 0.4 mm.

The metal support may be in the form of a sheet, or in the form of being processed into a cylindrical shape in advance.

(Adhesive layer)
The adhesive layer is a cured product made of a composition containing a thermosetting resin (hereinafter sometimes referred to as “adhesive composition”).

The adhesive composition preferably contains a polyvinyl resin.
The content of the polyvinyl resin in the adhesive composition is preferably 5 to 70% by mass, more preferably 10 to 50% by mass, and still more preferably 20 to 50% by mass.
When the content of the polyvinyl resin is in the above range, even if the photocured product of the photosensitive layer for printing relief described later has a wide hardness, it tends to stably maintain high adhesive strength.

Examples of the thermosetting resin contained in the adhesive layer include, but are not limited to, urea-based resins, melamine-based resins, phenol-based resins, epoxy-based resins, unsaturated polyester-based resins, and alkyd-based resins. And urethane resins.
Among these, from the viewpoint that the curing reaction occurs at a relatively low temperature and in a short time, and that the thermosetting reaction after the lamination to the metal support is easy to control, the flexibility control of the adhesive layer From the viewpoint, an epoxy resin and a urethane resin are preferable.
Furthermore, an epoxy resin is more preferable from the viewpoints of reducing the blocking property of the adhesive layer, suppressing the decrease in adhesive strength during storage over time, and improving the corrosion resistance of the metal support.
From the viewpoint of improving adhesiveness, the thermosetting resin preferably contains an amino resin, and examples of the amino resin include urea-based resins and melamine-based resins.
In addition, it exists in the tendency which expresses more preferable adhesiveness by using amino resins, such as the said urea-type resin and a melamine-type resin, together with an epoxy-type resin and a urethane-type resin.

  As the epoxy resin and urethane resin, known materials can be used and are not particularly limited.

The epoxy resin is an epoxy resin containing two or more oxirane rings in one molecule.
It is preferable that the adhesive composition contains an epoxy resin curing agent in addition to the epoxy resin and the polyvinyl resin as thermosetting resins.
Examples of the epoxy resin include, but are not limited to, for example, bisphenol A type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, polyglycidylamine type epoxy resin, alicyclic ring Formula-type epoxy resin etc. are mentioned.

The epoxy equivalent of the epoxy resin is preferably 100 to 20000 g / eq from the viewpoint of suppressing cohesive failure of the adhesive layer and the adhesive strength with the metal support. More preferably, it is 100-10000 g / eq, More preferably, it is 100-5000 g / eq. In addition, an epoxy resin that is liquid at room temperature is preferable because it has good leveling properties.
Epoxy resins may be used alone or in combination of two or more.
The epoxy equivalent can be measured by a method according to JIS K7236.

Examples of the epoxy resin curing agent include, but are not limited to, urea compounds, phenolic compounds, amine compounds, mercaptan compounds, acid anhydride compounds, dicyandiamide, Lewis acid complex compounds, and imidazoles. System compounds and the like.
These may be used alone or in combination of two or more.

  Examples of the urethane resin include, but are not limited to, for example, those obtained by a reaction between a polyester polyol or polyether polyol having two or more active hydrogen atoms in the molecule and a polyisocyanate compound. Can be mentioned.

Examples of the polyester polyol include, but are not limited to, for example, a condensed polyester polyol (such as a diol having a repeating polyester segment obtained by a polycondensation reaction between a glycol compound and a dicarboxylic acid compound), caprolactone opening, and the like. Examples thereof include ring-polymerized esters.
Examples of the glycol compound include, but are not limited to, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, 1,3-butanediol, hexanetriol, and trimethylolpropane.
Examples of the dicarboxylic acid compound include, but are not limited to, adipic acid, succinic acid, glutaric acid, azelaic acid, sebacic acid, maleic acid, terephthalic acid, isophthalic acid, and 1,5-naphthalenedicarboxylic acid. Etc.
These may be used alone or in combination of two or more.

Examples of the polyether polyol include, but are not limited to, polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, poly1,2-butylene glycol, polyoxyethylene / polyoxypropylene Examples include random copolymers, polyoxyethylene / polyoxypropylene block copolymers, polyoxyethylene / polyoxytetramethylene random copolymers, polyoxyethylene / polyoxytetramethylene block copolymers, and the like.
These may be used alone or in combination of two or more.

Examples of the polyisocyanate compound include, but are not limited to, tolylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, and diphenylmethane diisocyanate.
These may be used alone or in combination of two or more.

Moreover, as described above, the adhesive composition preferably contains a polyvinyl resin.
The content of the polyvinyl resin in the adhesive composition is preferably 5 to 70% by mass, more preferably 10 to 50% by mass, and still more preferably 20 to 50% by mass.
When the content of the polyvinyl resin is in the above range, even if the photocured product of the photosensitive layer for printing relief described later has a wide hardness, it tends to stably maintain high adhesive strength.
The polyvinyl resin is a resin obtained by addition polymerization of a compound having a vinyl group.
Examples of the compound having a vinyl group include, but are not limited to, vinyl alcohol, vinyl pyrrolidone, vinyl chloride, vinyl acetate, vinyl cinnamate, vinyl alkanoate, vinyl cyclohexane, N-vinyl carbazole, N -Vinyl imidazole, N-vinyl caprolactam, (meth) acrylic acid, (meth) acrylic acid ester compounds, and the like. Furthermore, homopolymers, copolymer polymers, and derivatives thereof (for example, acetalized products, alkyl etherified products, alkylesterified products, etc.) of these compounds can be used as the polyvinyl resin of the adhesive composition.

  As a polyvinyl resin, the viewpoint that the adhesive strength with the photosensitive layer for printing relief can be expressed even when the addition amount is relatively low without impairing the adhesive strength of the thermosetting resin to the metal support. Therefore, a polyvinyl chloride resin, a polyvinyl acetate resin, a polyvinyl chloride-vinyl acetate copolymer resin, and the like are preferable. Among these, from the viewpoint of excellent solubility in a coating solvent, polyvinyl acetate resin and polyvinyl chloride-vinyl acetate copolymer resin are more preferable, and polyvinyl chloride-vinyl acetate copolymer resin is more preferable.

  Vinyl compounds other than vinyl chloride and vinyl acetate may be copolymerized with the polyvinyl chloride resin, the polyvinyl acetate resin, and the polyvinyl chloride-vinyl acetate copolymer resin. Examples of vinyl compounds other than vinyl chloride and vinyl acetate include, but are not limited to, (meth) acrylic acid, alkyl ester compounds of (meth) acrylic acid, hydroxyalkyl ester compounds, vinyl alcohol, and dicarboxylic acids. Etc.

  The polyvinyl resin preferably contains a vinyl alcohol component as a constituent component in the molecule in a range of less than 5% by mass, and more preferably does not substantially contain it. The vinyl alcohol component here is one type of polymer unit containing a hydroxyl group, and examples thereof include those obtained by hydrolysis of polyvinyl acetate. When the content of the vinyl alcohol component is less than 5% by mass, the adhesive strength can be realized at a high level. From this viewpoint, the content of the vinyl alcohol component in the polyvinyl resin is more preferably 0% by mass. The content of the vinyl alcohol component is calculated by converting the hydroxyl value (mgKOH / g) analyzed by a method according to the test method for the hydroxyl value of a chemical specified in JIS K0070 into the content of the vinyl alcohol component in the sample. The vinyl alcohol content (% by mass) in the polyvinyl resin can be calculated.

  The molecular weight of the polyvinyl resin is preferably 100000 or less, more preferably 50000 or less, and more preferably 40000 or less from the viewpoint of adhesive strength with the photosensitive layer for printing relief and compatibility with the thermosetting resin. More preferably it is. In addition, from the viewpoint of maintaining the adhesive strength of the adhesive layer and chemical resistance, it is preferably 5000 or more, and more preferably 10,000 or more.

  In particular, when the thermosetting resin used for the adhesive layer is an epoxy resin, and these vinyl compounds other than vinyl chloride and vinyl acetate have a hydroxyl group, carboxylic acid, etc., a polyvinyl chloride resin, a polyvinyl acetate resin, The content of the vinyl compound other than vinyl chloride and vinyl acetate is preferably 15% by mass or less based on the total amount of monomers constituting the vinyl chloride-vinyl acetate copolymer resin. Setting the upper limit of the content in such a range is preferable from the viewpoint of suppressing interfacial peeling between the adhesive layer and the metal support, and the content is more preferably less than 5% by mass.

  In the adhesive composition used in the adhesive layer of the printing plate laminate for laser engraving of this embodiment, if necessary, a thermal polymerization inhibitor, an ultraviolet absorber, a light stabilizer, a dye, a pigment, a lubricant, an inorganic filler An agent, an organic filler, a plasticizer and the like can be further blended.

Examples of the thermal polymerization inhibitor include, but are not limited to, organotin stabilizers, phenol antioxidants, sulfur antioxidants, phosphorus antioxidants, and the like.
Examples of the ultraviolet absorber include, but are not limited to, salicylic acid ultraviolet absorbers, benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, and cyanoacrylate ultraviolet absorbers.
Examples of the light stabilizer include, but are not limited to, a hindered amine light stabilizer.
Examples of the dye include, but are not limited to, azo dyes, anthraquinone dyes, naphthol dyes, triphenylmentane dyes, polymethine dyes, sulfur dyes, and heavy metal ions such as chromium, copper, nickel, and cobalt. And complex salt dyes having a dihydroxyazobenzene structure.
Examples of the pigment include, but are not limited to, carbon black, titanium oxide, cobalt oxide, azo pigment, copper phthalocyanine pigment, and the like.
Examples of the lubricant include, but are not limited to, aliphatic hydrocarbon lubricants, higher fatty acid alcohol lubricants, higher fatty acid lubricants, fatty acid ester lubricants, fatty acid amide lubricants, and the like.
Examples of inorganic fillers and organic fillers include, but are not limited to, metal powders such as iron, copper, and nickel; carbon compounds such as carbon black, graphite, and carbon fiber; silica, alumina, and titanium oxide. Metal oxide such as aluminum hydroxide, hydroxide such as magnesium hydroxide; carbonate such as calcium carbonate and magnesium carbonate; sulfate such as calcium sulfate; silicate such as talc, clay and mica; polystyrene, polyethylene And fine particles of various synthetic resins such as polyamide (nylon (trademark), etc.
Examples of the plasticizer include, but are not limited to, ester compounds such as phthalic acid, adipic acid, sebacic acid, phosphoric acid, acetylcitric acid, trimellitic acid, polyester plasticizers, paraffin, rosin and the like. Is mentioned.

The lamination method for forming the adhesive layer on the surface of the metal support is not particularly limited, and a known method can be applied.
For example, after applying a solution in which an adhesive composition containing a thermosetting resin, which is a material of the adhesive layer, is mixed with a solvent so as to have a substantially constant thickness on the surface of the metal support, and drying the solvent A preferable method is to form an adhesive layer on the surface of the metal support by baking.
The solvent to be used is not particularly limited as long as it can dissolve the adhesive composition, and examples thereof include methanol, methyl ethyl ketone, ethyl acetate, toluene, and cyclohexanone.
The temperature of the baking process is not particularly limited, but is preferably 100 to 220 ° C.
The baking time is not particularly limited, but is preferably about 5 minutes to 2 hours.
Setting the baking temperature and time within this range is preferable from the viewpoint of securing the adhesive strength between the adhesive layer and the metal support.

The adhesive layer adheres on the surface 1 m ² of the metal support from the viewpoint of firmly bonding the metal support to the photosensitive layer for printing relief described later and suppressing cohesive failure of the adhesive layer. the formation amount of wood layer, preferably to 0.5 to 10 g / m ^2, and more preferably to 1-8 g / m ^2.
From the same viewpoint, the thickness of the adhesive layer is preferably 0.5 to 10 μm, and more preferably 1 to 8 μm.

Note that the adhesive layer may be a single layer or a plurality of two or more layers.
When the adhesive layer has a two-layer structure, the first adhesive layer is first formed on the surface of the metal support by the above-described method, and then the second adhesive layer is changed to the first adhesive layer. It is possible to employ a method of further forming on the surface of the film.
In this case, the first adhesive layer and the second adhesive layer may have the same component composition or different component compositions.

The formation amount of the first adhesive layer on the surface 1m ² of the metal support is 0.5 to 10 g / m ² from the viewpoint that the cohesive failure of the first adhesive layer can be effectively suppressed. It is preferably 1 to 8 g / m ² .
From the same viewpoint, the thickness of the first adhesive layer is preferably 0.5 to 10 μm, and more preferably 1 to 8 μm.
Furthermore, the amount of the second adhesive layer formed on the surface 1 m ² of the first adhesive layer is preferably 0.5 to 10 g / m ² and 1 to 8 g / m ² from the same viewpoint. It is more preferable that
From the same viewpoint, the thickness of the second adhesive layer is preferably 0.5 to 10 μm, and more preferably 1 to 8 μm.
Here, as an example, the case of two or more layers has been described, but the case of using three or more layers can be similarly manufactured.

When the adhesive layer is composed of three or more layers, the adhesive composition used for constituting the adhesive layer (the sum of the compositions used for constituting each layer) is bonded. The total content of the thermosetting resin in the total amount of the material composition is preferably 30 to 95% by mass, more preferably 50 to 90% by mass, and further preferably 50 to 80% by mass. .
When the total content of the thermosetting resin in the adhesive composition for constituting the adhesive layer is within the above range, the adhesive strength of both the metal support and the photosensitive layer for printing relief described later is high. In addition, the cohesive failure of the adhesive layer and chemical resistance can be satisfied at a higher level.

In addition, regarding the component composition of the adhesive composition used for constituting the adhesive layer (the total of the compositions used for constituting each layer), the total content of the polyvinyl resin in the total amount of the adhesive composition is 5 to 70% by mass, more preferably 10 to 50% by mass, and still more preferably 20 to 50% by mass.
When the total content of the polyvinyl resin in the adhesive composition for constituting the adhesive layer is within the above range, even if the photocured product of the photosensitive layer for printing relief described later has a wide hardness, high adhesion There is a tendency that the strength can be stably maintained.

(Photosensitive layer for printing relief)
The photosensitive layer for printing relief contains an unsaturated polyurethane prepolymer, an ethylenically unsaturated compound, and a photopolymerization initiator.
As will be described later, the photosensitive layer for printing relief of the printing plate laminate for laser engraving of the present embodiment is basically after curing, but includes the layer before curing within a range that is essentially free of problems. May be.

The unsaturated polyurethane prepolymer is a compound having a plurality of urethane bonds in the molecule and having an ethylenically unsaturated group and capable of binding to other compounds by a polymerization reaction.
Examples of the method for producing the unsaturated polyurethane prepolymer include the following methods (i) and (ii).
(I) A polyol and a polyisocyanate are reacted to form a polyurethane having an isocyanate group at a terminal so as to have a predetermined molecular weight, and then the polyurethane, an active hydrogen and an ethylenically unsaturated group in the molecule A method of reacting a compound having
(Ii) A polyol and a polyisocyanate are reacted to form a polyurethane having a hydroxyl group at a terminal so as to have a predetermined molecular weight, and then the polyurethane, an isocyanate group and an ethylenically unsaturated group are formed in the molecule. A method of reacting a compound having the same.

Examples of the polyol contained as a polymerization monomer in the unsaturated polyurethane prepolymer include, but are not limited to, for example, polyether polyol, polyester polyol, polyether polyester copolymer polyol, polycarbonate polyol, and polybutadiene polyol. Is mentioned.
These may be used alone or in combination of two or more.

Examples of the polyether polyol include, but are not limited to, polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, poly1,2-butylene glycol, polyoxyethylene / polyoxypropylene Examples include random copolymers, polyoxyethylene / polyoxypropylene block copolymers, polyoxyethylene / polyoxytetramethylene random copolymers, polyoxyethylene / polyoxytetramethylene block copolymers, and the like.
These may be used alone or in combination of two or more.

Examples of the polyester polyol include, but are not limited to, a condensed polyester polyol, that is, a diol having a repeating polyester segment obtained by a polycondensation reaction between a glycol compound and a dicarboxylic acid compound.
Examples of such diols include, but are not limited to, adipic acid ester diols.
Examples of the adipic ester diol include, but are not limited to, poly (ethylene glycol adipate) diol, poly (diethylene glycol adipate) diol, poly (propylene glycol adipate) diol, and poly (1,4-butane). Glycol adipate) diol, poly (1,6-hexaneglycol adipate) diol, poly (2-methylpropaneglycol adipate) diol, poly (3-methyl-1,5-pentaneglycol adipate) diol, poly (neopentyl glycol) Adipate) diol, poly (1,9-nonaneglycol adipate) diol, poly (2-methyloctaneglycol adipate) diol, polycaprolactone diol, poly (β-methyl-δ-valerolacto) N) diol.

  Examples of the dicarboxylic acid compound constituting the polyester segment include, but are not limited to, adipic acid, but include, for example, succinic acid, glutaric acid, azelaic acid, sebacic acid, maleic acid, terephthalic acid, isophthalic acid, 1 , 5-naphthalenedicarboxylic acid and the like.

In addition, as illustrated above, the polyester segment is generally constituted by a polycondensation reaction with a single kind of diol compound and a dicarboxylic acid compound.
However, it is also possible to form a polyester segment by using a plurality of either one or both compounds and polycondensing them at an arbitrary ratio.

As the polyester polyol, in addition to the above-mentioned condensed polyester polyol, for example, lactone polyester polyol, polycarbonate diol and the like can be used.
These may be used alone or in combination of two or more.

The polyether polyester copolymer polyol is a copolymer having a structure in which a repeating unit forming a molecular chain of the above-mentioned polyether polyol and a repeating unit forming a molecular chain of the above-mentioned polyester polyol are combined in a block or randomly. A polymer etc. are mentioned.
A polyether polyester copolymer polyol may be used individually by 1 type, and may use 2 or more types together.

  As the polycarbonate polyol, a compound represented by the following formula (1), a compound represented by the following formula (2), and the like are preferable.

(In Formula (1), each R ₁ independently represents a linear or branched hydrocarbon group having 2 to 20 carbon atoms, and the plurality of R ₁ may have the same carbon number, A may represent an integer of 1 or more.

(In Formula (2), each R ₂ independently represents a linear or branched hydrocarbon group having 2 to 20 carbon atoms, and the plurality of R ₂ may have the same carbon number, N may each independently represent an integer of 2 to 20, and b represents an integer of 1 or more.)

Specific examples of the polycarbonate polyol include, but are not limited to, for example, 4,6-polyalkylene carbonate diol, 8,9-polyalkylene carbonate diol, and 5,6-polyalkylene carbonate diol. Etc.
These may be used alone or in combination of two or more.

Examples of the polybutadiene polyol include, but are not limited to, for example, a mixture of poly (1,4-butanediene) glycol and a hydrogenated product thereof, poly (1,2-butadiene) glycol and a hydrogenated product thereof. Examples thereof include a mixture, a mixture of poly (1,2- / 1,4-butadiene) glycol and its water additive, and the like.
These may be used alone or in combination of two or more.

  The number average molecular weight of the polyol is within the range of 500 to 15000 from the viewpoint of imparting excellent flexibility and elastic properties to the photosensitive layer for printing relief constituting the printing plate laminate for laser engraving of the present embodiment. It is preferable that it is, More preferably, it is 500-10000, More preferably, it is the range of 500-5000.

Examples of the polyisocyanate include, but are not limited to, tolylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, and the like.
These may be used alone or in combination of two or more.

  Examples of the compound having an active hydrogen and an ethylenically unsaturated group in the molecule include, but are not limited to, hydroxypropyl (meth) acrylate, hydroxyethyl (meth) acrylate, polypropylene glycol mono ( Examples include meth) acrylate, polyethylene glycol mono (meth) acrylate, glycerin mono (meth) acrylate, and glycerin di (meth) acrylate.

  The compound having an isocyanate group and an ethylenically unsaturated group in the molecule is not limited to the following, and examples thereof include (meth) acryloyloxyethyl isocyanate.

In addition, you may implement reaction which adds a (meth) acryl group with respect to the molecular terminal of the polyurethane manufactured by the method of said (i) (ii).
In the present specification, a compound capable of reacting with a molecular terminal of polyurethane to add a (meth) acryl group may be referred to as a “(meth) acrylating agent”.
Examples of the (meth) acrylating agent include the (meth) acryloyloxyethyl isocyanate.

The number average molecular weight of the unsaturated polyurethane prepolymer is preferably from 1,000 to 100,000, more preferably from 5,000 to 100,000, and even more preferably from 5,000 to 50,000.
By setting the number average molecular weight of the unsaturated polyurethane prepolymer to the above lower limit or more, it is possible to impart good mechanical strength to the obtained printing relief photosensitive layer, and it is also high for repeated use of the printing plate and rough handling. Durability can be demonstrated.
By ensuring that the number average molecular weight of the unsaturated polyurethane prepolymer is not more than the above upper limit, the fluidity necessary for forming the photosensitive layer for printing relief on the surface of the metal support on which the adhesive layer is laminated is ensured. it can.
Unless otherwise specified in this specification, the number average molecular weight is a value calculated as a polystyrene equivalent value obtained in accordance with GPC measurement described in Examples described later.
The number average molecular weight of the unsaturated polyurethane prepolymer can be controlled by adjusting the type, amount and polymerization conditions of the polymer.

Assuming the case where the region corresponding to the relief image of the photosensitive layer for printing relief is cured with actinic rays and then the plate is made by a method of developing the region other than the relief image with an aqueous cleaning solution, the unsaturated polyurethane prepolymer is The polyoxyethylene segment is preferably contained, and the content of the polyoxyethylene segment is preferably 5 to 25% by mass, more preferably 10 to 20% by mass.
Dispersibility of the composition constituting the photosensitive layer for printing relief with respect to the aqueous cleaning liquid can be ensured by setting the content of the polyoxyethylene segment to the above lower limit value or more, and the content of the polyoxyethylene segment is not more than the above upper limit value. By doing so, the swelling property of the cured product of the photosensitive layer for relief with respect to the printing ink can be suppressed to a certain value or less, and the relief can be prevented from swelling during printing and the printing quality from being deteriorated.

The unsaturated urethane prepolymer described above may be used alone or in combination of two or more.

The ethylenically unsaturated compound contained in the photosensitive layer for printing relief is a compound having an ethylenically unsaturated group in the molecule, and is not limited to the following, for example, an unsaturated carboxylic acid Ester compounds of unsaturated carboxylic acids; (meth) acrylamide and derivatives thereof; allyl compounds; maleic acid, maleic anhydride, fumaric acid and esters thereof; and compounds having other ethylenically unsaturated groups.
These may be used alone or in combination of two or more.

Examples of the unsaturated carboxylic acid include, but are not limited to, (meth) acrylic acid, vinyl carboxylate, crotonic acid, myristoleic acid, palmitoleic acid, oleic acid, and the like.
Among these, (meth) acrylic acid is preferable from the viewpoint of polyaddition reactivity with the (meth) acryl group which is an unsaturated double bond modified at the molecular main chain terminal of the unsaturated polyurethane prepolymer.

  Examples of the unsaturated carboxylic acid ester compounds include, but are not limited to, alkyl (meth) acrylates, cycloalkyl (meth) acrylates, halogenated alkyl (meth) acrylates, and alkoxyalkyl (meth) acrylates. , Hydroxyalkyl (meth) acrylate, aminoalkyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, allyl (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate; alkylene glycol Mono- or di (meth) acrylate, polyoxyalkylene glycol mono- or di (meth) acrylate; trimethylolpropane tri (meth) acrylate; glycerin mono-, di- or Tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate.

  The (meth) acrylamide derivative is not limited to the following, but, for example, (meth) acrylamide or diacetone (meth) acrylamide that is N-substituted or N, N′-substituted with an alkyl group or a hydroxyalkyl group. , N, N′-alkylenebis (meth) acrylamide and the like.

  Examples of the allyl compound include, but are not limited to, allyl alcohol, allyl isocyanate, diallyl phthalate, triallyl cyanurate, and the like.

  Examples of the maleic acid ester and fumaric acid ester include, but are not limited to, alkyl, halogenated alkyl, alkoxyalkyl mono- or dimaleate, and fumarate.

  Examples of other compounds having an ethylenically unsaturated group include, but are not limited to, styrene, vinyl toluene, divinyl benzene, N-vinyl carbazole, N-vinyl pyrrolidone, and the like.

From the viewpoint of controlling the flexibility and elastic properties required for the laser engraving printing plate laminate of the present embodiment, the mechanical strength necessary for durability, the swelling property with respect to ink, and the like as the ethylenically unsaturated compound. , Propylene glycol monomethacrylate, polyoxypropylene glycol monomethacrylate, diethylene glycol monoethyl ether mono (meth) acrylate, diethylene glycol monobutyl ether mono (meth) acrylate, diethylene glycol mono-2-ethylhexyl ether mono (meth) acrylate, triethylene glycol monohexyl ether Mono (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, phenoxyethyl (meth) acrylate, N, N-diethyl Minoechiru (meth) acrylate, and one or more compounds selected from the group consisting of polyoxypropylene glycol di (meth) acrylate.
In the ethylenically unsaturated compound, aliphatic propylene glycol monomethacrylate, polyoxypropylene glycol monomethacrylate, diethylene glycol monoethyl ether mono (meth) acrylate, diethylene glycol monobutyl ether mono (meth) acrylate, diethylene glycol mono-2-ethylhexyl Ether mono (meth) acrylate, triethylene glycol monohexyl ether mono (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, phenoxyethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, and One or more compounds selected from the group consisting of polyoxypropylene glycol di (meth) acrylate are Odor less preferred when Za engraving.

The blending amount of the ethylenically unsaturated compound in the composition constituting the photosensitive layer for printing relief is preferably 10 to 150 parts by mass with respect to 100 parts by mass of the unsaturated polyurethane prepolymer component described above. More preferably, it is -100 mass parts, More preferably, it is 20-90 mass parts.
Setting the blending amount of the ethylenically unsaturated compound within the above range realizes the fluidity necessary for laminating the photosensitive layer for printing relief on the surface of the metal support on which the adhesive layer described above is laminated. From the viewpoint of

Examples of the photopolymerization initiator include, but are not limited to, hydrogen abstraction initiators and cleavage initiators.
Examples of the hydrogen abstraction type initiator include, but are not limited to, benzophenone, benzyl, diacetyl, 9,10-anthraquinone, and the like.
Examples of the cleavage type initiator include, but are not limited to, benzoin alkyl ethers such as benzoin, benzoin ethyl ether, benzoin-n-propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, diphenyl sulfide, 2 , 2-dimethoxy-2-phenylacetophenone and the like.
These may be used alone or in combination of two or more.

Here, it is preferable to use the said photoinitiator in combination with a sensitizer from a viewpoint of improving the reactivity.
Examples of such sensitizers include, but are not limited to, triethanolamine, methyldiethanolamine, triisopropanolamine, Michler's ketone, 4,4′-diethylaminophenone, 4-diethylaminobenzoic acid ethyl ester, and the like. Amines; dyes such as eosin and thiocin.
In particular, when a hydrogen abstraction type initiator such as benzophenone is used as the photopolymerization initiator component, it is preferable to use such a sensitizer.

The blending amount of the photopolymerization initiator in the composition constituting the photosensitive layer for printing relief is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the unsaturated polyurethane prepolymer. It is more preferably 1 to 5 parts by mass, and further preferably 0.5 to 5 parts by mass.
Setting the blending amount of the photopolymerization initiator within the above range means that the storage stability of the composition, which is the material of the photosensitive layer for printing relief, the photocuring speed, and the physical properties of the photosensitive layer for printing relief are at a high level. This is preferable because both can be balanced.

  Other additives such as thermal polymerization inhibitors, ultraviolet absorbers, light stabilizers, dyes, pigments, lubricants, inorganic fillers, organic fillers, plasticizers and the like are further added to the photosensitive layer for printing relief as necessary. Can be blended.

Examples of the thermal polymerization inhibitor include, but are not limited to, organotin stabilizers, phenol antioxidants, sulfur antioxidants, phosphorus antioxidants, and the like.
Examples of the ultraviolet absorber include, but are not limited to, salicylic acid ultraviolet absorbers, benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, and cyanoacrylate ultraviolet absorbers.
Examples of the light stabilizer include, but are not limited to, a hindered amine light stabilizer.
Examples of the dye include, but are not limited to, azo dyes, anthraquinone dyes, naphthol dyes, triphenylmentane dyes, polymethine dyes, sulfur dyes, and heavy metal ions such as chromium, copper, nickel, and cobalt. And complex salt dyes having a dihydroxyazobenzene structure.
Examples of the pigment include, but are not limited to, carbon black, titanium oxide, cobalt oxide, azo pigment, copper phthalocyanine pigment, and the like.
Examples of the lubricant include, but are not limited to, aliphatic hydrocarbon lubricants, higher fatty acid alcohol lubricants, higher fatty acid lubricants, fatty acid ester lubricants, fatty acid amide lubricants, and the like.
Examples of inorganic fillers and organic fillers include, but are not limited to, metal powders such as iron, copper, and nickel; carbon compounds such as carbon black, graphite, and carbon fiber; silica, alumina, and titanium oxide. Metal oxide such as aluminum hydroxide, hydroxide such as magnesium hydroxide; carbonate such as calcium carbonate and magnesium carbonate; sulfate such as calcium sulfate; silicate such as talc, clay and mica; polystyrene, polyethylene And fine particles of various synthetic resins such as polyamide (nylon (trademark), etc.
Examples of plasticizers include, but are not limited to, ester compounds such as phthalic acid, adipic acid, sebacic acid, phosphoric acid, acetylcitric acid, trimellitic acid; polyester plasticizers, paraffin, rosin, etc. Is mentioned.

In particular, in the case where a printing pattern is formed by laser engraving technology in which a region other than the relief image is burned off with a laser beam after the photosensitive layer for printing relief is cured by irradiation with active light, the inorganic filler or The organic filler is preferably a porous body.
Examples of the porous body include, but are not limited to, porous silica, mesoporous silica, silica-zirconia porous gel, mesoporous molecular sieve, porous alumina, porous glass, and the like.

Among the porous bodies, the average pore diameter of the inorganic porous body is preferably 1 nm to 1000 nm.
The pore volume of the inorganic porous body is preferably 0.1 mL / g to 10 mL / g.
The number average particle diameter of the inorganic porous material is preferably 10 μm or less.
And it is more preferable that the average pore diameter, pore volume, and number average particle diameter of the inorganic porous body are in the above ranges, respectively.
By satisfying these conditions, it is preferable because the liquid component generated during engraving can be effectively captured and transformed into powdered debris.
The average pore diameter and pore volume can be measured by a nitrogen adsorption method.
The number average particle size can be measured using a laser scattering type particle size distribution measuring apparatus.

In this embodiment, the method of laminating the photosensitive layer for printing relief on the adhesive layer laminated on the surface of the metal support is not particularly limited, and a known method can be applied.
For example, a method of extruding a photosensitive resin composition for forming a photosensitive layer for printing relief having a viscosity that exhibits fluidity onto an adhesive layer using a T-die, or after applying an arbitrary amount Various known methods such as a method of stretching with a doctor can be mentioned.
The thickness of the photosensitive layer for printing relief is preferably adjusted in the range of 0.1 mm to 10 mm for use in various printing applications.
In flexographic printing and dry offset printing, the thickness of the photosensitive layer for printing relief is more preferably 0.1 mm to 5 mm. More preferably, it is 0.1 mm-3 mm.

The photosensitive layer for printing relief constituting the printing plate laminate for laser engraving of the present embodiment may have a single layer configuration of only one layer or a multilayer configuration of two or more layers.
When two layers of photosensitive layers for printing relief are used, for example, the first photosensitive layer for printing relief is first formed on the surface of the adhesive layer by the method described above, and then the second photosensitive layer for printing relief. A method of further forming a conductive layer on the surface of the first photosensitive layer for printing relief can be employed. In this case, the first printing relief photosensitive layer and the second printing relief photosensitive layer may have the same component composition or different component compositions.

In order to adjust the photosensitive layer for printing relief to a certain thickness, after forming the photosensitive resin composition layer forming the photosensitive layer for printing relief, the surface of the layer has transparency to actinic rays. The film is preferably laminated as a cover film, and then compressed using a roll having a rubber or metal surface, a metal plate, a glass plate, or the like.
Moreover, when shape | molding in a sheet form, suitable viscosity may be required in order to apply the photosensitive layer for printing relief to fixed thickness, suppressing mixing of a bubble. The viscosity at 35 ° C. is preferably 1000 mPa · s to 10000000 mPa · s. More preferably, it is 5000 mPa * s-1 million mPa * s, More preferably, it is 10000 mPa * s-500000 mPa * s.

The printing plate laminate for laser engraving of this embodiment is a layer obtained by curing the photosensitive layer for printing relief by, for example, irradiating the photosensitive layer for printing relief with light.
The photosensitive layer for printing relief may be cured by heating.
Thereby, the outstanding adhesive strength with respect to an adhesive material layer can be expressed.
Unless otherwise specified, “cured” and “cured product” in this specification include not only complete curing but also states such as partial curing and semi-curing.
And it includes not only the state where the entire surface of the photosensitive layer for printing relief is cured, but also the state where at least a part of the surface is cured.

As a light source used for light irradiation, although not limited to the following, an active light source is mentioned, for example.
Examples of the actinic ray source include, but are not limited to, a low pressure mercury lamp, a high pressure mercury lamp, an ultraviolet fluorescent lamp, a carbon arc lamp, a xenon lamp, a zirconium lamp, and the sun.
Examples of the irradiation with actinic rays include a method of irradiating a photosensitive layer for printing relief with actinic rays.
When the method of photocuring the entire photosensitive layer for printing relief is applied, it is necessary to subsequently produce a desired printing relief shape by a predetermined engraving technique.
An example of the engraving technique is burning with a laser beam.

  In the case where the entire surface of the photosensitive layer for printing relief is irradiated with actinic rays and cured, printing is performed after photocuring by irradiation with actinic rays in order to adjust the thickness of the printing plate laminate for laser engraving of this embodiment. You may perform mechanical processing, such as grinding and grinding | polishing, to the photosensitive layer for relief.

The photosensitive layer for printing relief is preferably designed in consideration that the hardness of the cured product is in an appropriate range according to the printing method, the material of the printing material, and the required printing quality.
When evaluating the hardness of the cured product in the present embodiment, for example, Shore A hardness, Shore D hardness, or the like can be used as an index.
The Shore A hardness tends to be evaluated with high accuracy in a more flexible region, and the Shore D hardness tends to be evaluated with high accuracy in a harder region.
In addition, Shore A hardness and Shore D hardness can be measured based on the method as described in the Example mentioned later.

  When the hardness of the photosensitive layer for printing relief is high (for example, the hardness with Shore D hardness as an index, etc.), the cohesive force inside the photosensitive layer for printing relief is usually high, so that adhesion with the adhesive layer It tends to be difficult to set the strength high. However, according to the present embodiment, even when the hardness of the photosensitive layer for printing relief is high (for example, when the photosensitive layer for printing relief has a Shore D hardness of 10 to 80 degrees), By using an adhesive composition, it is possible to achieve a high level of adhesive strength between the photosensitive layer for printing relief and the adhesive layer.

In the printing plate laminate for laser engraving of this embodiment, the metal support, the adhesive layer, and the photosensitive layer for printing relief are firmly bonded to each other.
The adhesive strength can be evaluated by measuring the strength when the photosensitive layer for printing relief laminated on the adhesive layer is peeled off.
When the relief depth (depth of the uncured component to be removed) of the printing plate obtained from the printing plate laminate for laser engraving of this embodiment is shallower than the thickness of the photosensitive layer for printing relief (printing plate lamination for laser engraving) In the state where the printing relief is processed on the body, the photosensitive layer for printing relief remains in the area corresponding to the non-image area of printing), for the printing relief from the printing plate laminate for laser engraving in the actual printing operation The adhesive strength for preventing the photosensitive layer from peeling is preferably 2 N / cm or more, more preferably 2.5 N / cm or more, and further preferably 2.9 N / cm or more.
In addition, adhesive strength is measured based on the method as described in the Example mentioned later.

  When the relief depth of the printing plate obtained from the printing plate laminate for laser engraving of this embodiment is the same as the thickness of the photosensitive layer for printing relief (in the state where the printing relief is processed on the photosensitive resin printing plate laminate) The photosensitive layer for printing relief does not remain in the area corresponding to the non-image area of printing), and the adhesive area between the photosensitive layer for printing relief and the adhesive layer tends to be small. The adhesive strength for preventing the photosensitive layer for printing relief from peeling from the laminate for printing is preferably 4.0 N / cm or more, more preferably 5.0 N / cm or more, and 6.0 N / cm. More preferably, it is the above.

Furthermore, after photocuring the photosensitive layer for printing relief, assuming a case where the printing plate laminate for laser engraving of this embodiment is cut with a shear cutter, etc., from the viewpoint of reducing peeling of the cut end face, An adhesive strength of 6.0 N / cm or more is required.
When cutting the printing plate laminate for laser engraving of this embodiment, it is preferable to use a single blade, and the blade angle is preferably 15 ° to 75 °.
The adhesive strength of the photosensitive layer for printing relief is preferably 6 N / cm or more as described above, and is not peelable (that is, the cured product of the photosensitive layer for printing relief is torn off in the peeling test method described later). It is even more preferable that it is in a state where it cannot be peeled off.

In the printing plate laminate for laser engraving of this embodiment, the above adhesive strength can be realized by finding a cured printing relief photosensitive layer containing an unsaturated polyurethane prepolymer and an optimum adhesive.
In addition, even when stored for a long time (for example, when stored at 50 ° C. for about 3 months), the adhesive strength can be maintained, and excellent adhesive strength can be stably exhibited.

The adhesive strength for preventing the release of the photosensitive layer for printing relief from the laminate for the photosensitive resin printing plate of the present embodiment is suitable as long as it is in the above numerical range, but as a peeling form at that time, a metal support and Interfacial failure that occurs between adhesive layers, interfacial failure that occurs between adhesive layers and photosensitive layers for printing relief, cohesive failure that occurs inside adhesive layers, cohesive failure that occurs within photosensitive layers for printing relief, etc. As a peeling form, cohesive failure occurring inside the photosensitive layer for printing relief is preferable.
This is because the adhesive strength at other locations is stronger than that.
In the adhesion strength measurement, the cohesive failure of the photosensitive layer for printing relief indicates that the respective interfaces are adhered beyond the strength of the photosensitive layer for printing relief designed according to the printing purpose. Therefore, it can be said that this is a preferred form.

  Hereinafter, the present embodiment will be described more specifically with specific examples and comparative examples. However, the present embodiment is not limited to the following examples.

[Production Example 1] Production of photosensitive resin composition A for forming photosensitive layer for printing relief 1200 g of poly (3-methyl-1,5-pentanediol adipate) diol (hydroxyl value: 37 KOHmg / g, average molecular weight: 3000, trade name “Kurapol P3010” (manufactured by Kuraray Co., Ltd.) and 800 g of polyoxyethylene (EO) -oxypropylene (PO) block copolymerized diol (hydroxyl value: 44 KOH mg / g, average molecular weight: 2550, EO content 30 mass %, 0.09 g of dibutyltin dilaurate (hereinafter abbreviated as “BTL”) is added to the mixture with the product name “Sanix PL2100” (manufactured by Sanyo Chemical Industries) until uniform at 40 ° C. Stir to obtain a mixture.
To the obtained mixture, 136.9 g of tolylene diisocyanate (trade name “Coronate T80”, manufactured by Nippon Polyurethane Co., Ltd., hereinafter abbreviated as “TDI”) was added and further stirred.
When the mixture became uniform, the mixture was heated to 80 ° C. and then reacted for about 4 to 5 hours to prepare a prepolymer precursor having isocyanate groups at both ends.
About 387.2 g of poly (oxypropylene) glycol monomethacrylate (average molecular weight 380, trade name “Blenmer PP”, manufactured by NOF Corporation, hereinafter abbreviated as “PPM”) was added to the prepolymer precursor. The mixture was reacted for 2 hours to obtain an unsaturated polyurethane prepolymer composition A. PPM is a (meth) acrylating agent for (meth) acrylating the prepolymer precursor molecule terminal, and the amount thereof was added in excess of the theoretical amount in order to carry out the reaction quickly and stably.
Therefore, unsaturated polyurethane prepolymer composition A was a mixture of unsaturated polyurethane prepolymer A and excess PPM.

The number average molecular weight and the like of the unsaturated polyurethane prepolymer A were determined by performing GPC measurement by the following method.
<GPC measurement method>
GPC measurement was performed under the following conditions to determine the number average molecular weight in terms of polystyrene. Moreover, the content of the high molecular weight substance derived from the unsaturated polyurethane prepolymer component excluding the unreacted component of PPM added excessively at the time of production was determined from the peak area ratio (%) obtained by GPC measurement. As a result, the number average molecular weight of the high molecular weight substance derived from the unsaturated polyurethane prepolymer A component was 22500, and the content of the high molecular weight substance in the prepolymer composition was about 87% by mass. The remaining low molecular weight component of about 13% by mass was a reaction residue of PPM that was added in excess to (meth) acrylate the prepolymer precursor molecular ends.
Equipment: “HLC-8220GPC” manufactured by Tosoh Corporation
Column: “TSLgelGMMHXL” manufactured by Tosoh Corporation
Solvent: Tetrahydrofuran Flow rate: 1 ml / min Injection volume: 100 microliters Detector: RI detector Calibration curve standard: Polystyrene (molecular weight 500 to 1260000)
Sample: 0.3 mass% tetrahydrofuran solution

  Unsaturated polyurethane prepolymer composition A: 114.9 parts by mass (from the GPC measurement results, unsaturated polyurethane prepolymer A: 100 parts by mass, reaction residue PPM: 14.9 parts by mass), methacrylic acid 2- (2-butoxyethoxy) ethyl ester (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester AK-8”): 18.6 parts by mass, diethylene glycol-2-ethylhexyl ether acrylate (manufactured by Toagosei Co., Ltd., trade name “Aronix” M-120 "): 18.6 parts by mass, trimethylolpropane trimethacrylate (trade name" SR350J ", manufactured by Sartomer): 1.7 parts by mass, 2,2-dimethoxy-2-phenylacetophenone (Ciba Specialty Chemicals) Product name “IRGACURE651”): 0.93 parts by mass, 2, 6 Di-t-butyl-p-cresol (trade name “IONOL”, manufactured by Japan Chemtech Co., Ltd.): 1.6 parts by mass are added and mixed at 60 ° C. for about 1 hour to form a photosensitive layer for printing relief. Resin composition A was obtained.

(Shore A hardness)
The photosensitive resin composition A was cured by the following method to obtain a cured product, and its Shore A hardness was measured.
Using a 1 mm thick rubber as a spacer, sandwich the photosensitive resin composition A between two 5 mm thick glass plates via a polyethylene terephthalate film, and after adjusting the thickness, each side of the front and back surfaces of the UV fluorescent light. Irradiation was performed at an exposure amount of 1200 mJ, and photocuring was performed.
The obtained photocured product of the photosensitive resin composition A was left in a constant temperature and humidity room at a temperature of 20 ° C. and a relative humidity of 70% for one day, and the Shore A hardness was measured.
The measurement was performed using a JIS constant pressure loader GS-710 (according to ASTM D2240A, JIS K6253A, ISO 7619A, manufactured by Teclock Co., Ltd.) with a 1 kg load, and reading the value 15 seconds after the start of measurement.
As a result, the Shore A hardness of the photocured product of the photosensitive resin composition A was 40 degrees.

[Production Example 2] Production of photosensitive resin composition B for forming photosensitive layer for printing relief 2000 g of polycarbonate diol (hydroxyl value 55.4 KOHmg / g, number average molecular weight 2025, manufactured by Asahi Kasei Chemicals Corporation, trade name "Duranol T4672 )), 0.04 g of BTL was added and stirred at 40 ° C. until uniform, and 119.3 g of TDI was added and further stirred.
When the mixture became uniform, the mixture was heated to 80 ° C., reacted for about 3 to 4 hours, and the disappearance of isocyanate groups was confirmed using IR spectroscopy, and a prepolymer precursor having hydroxyl groups at both ends was prepared. did.
To the prepolymer precursor, 95.8 g of 2-methacryloyloxyethyl isocyanate (trade name “Karenz MOI” manufactured by Showa Denko KK) was added and reacted for about 3 hours to obtain an unsaturated polyurethane prepolymer composition B. Obtained.
The unsaturated polyurethane prepolymer composition B was subjected to GPC measurement in the same manner as in [Production Example 1]. As a result, the number average molecular weight of the high molecular weight substance derived from the prepolymer component was 7700, and the prepolymer composition The content of the high molecular weight substance was about 100% by mass.
Unsaturated polyurethane prepolymer composition B: 100 parts by mass (corresponding to 100 parts by mass of unsaturated polyurethane prepolymer B from GPC measurement results), phenoxyethyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “ Light ester PO "): 46.3 parts by mass, trimethylolpropane trimethacrylate (trade name" SR350J ", manufactured by Sartomer): 19.7 parts by mass, 2,2-dimethoxy-2-phenylacetophenone (Ciba Specialty Chemicals) Manufactured, trade name “IRGACURE651”): 3.0 parts by mass, benzophenone (manufactured by Asahi Kasei Finechem): 0.8 parts by mass, “2,6-di-t-butyl-p-cresol (manufactured by Japan Chemtech, Product name “IONOL”): 1.0 part by mass, the product name “Silo as an inorganic porous material” Fair C-1504 "(Fuji Silysia Chemical Ltd., porous fine powdered silica, number average particle diameter: 4.5 [mu] m, a specific surface area: 520m ² / g, average pore diameter: 12 nm, pore volume: 1.5 ml / g, oil absorption: 290 ml / 100 g): 8.0 parts by mass were added and mixed at 60 ° C. for about 1 hour to obtain a photosensitive resin composition B.

(Shore D hardness)
In addition, about the photosensitive resin composition B, the cured | curing material was produced with the following method and Shore D hardness was measured.
Using a 1 mm thick rubber as a spacer, sandwich the photosensitive resin composition B between two 5 mm thick glass plates via a polyethylene terephthalate film, and after adjusting the thickness, each of the front and back surfaces of each UV fluorescent light It was irradiated with an exposure amount of 1200 mJ and photocured to obtain a photocured product.
The resulting photocured product of the photosensitive resin composition B was left in a constant temperature and humidity room at a temperature of 20 ° C. and a relative humidity of 70% for one day, and the Shore D hardness was measured.
The measurement was performed using a JIS constant pressure loader GS-710 (according to ASTM D2240D, JIS K7215D, ISO R868D, manufactured by Teclock Corporation) installed in the same room with a 5 kg load, and the value 15 seconds after the start of measurement was read.
As a result, the Shore D hardness of the photocured product of the photosensitive resin composition B was 55 degrees.

[Example 1]
First, "jER (registered trademark) resin 834" which is an epoxy thermosetting resin (Mitsubishi Chemical Corporation, molecular weight: about 470, epoxy equivalent: 230 to 270 g / eq, hereinafter abbreviated as "epoxy resin 834"). : 100 parts by mass, “jER Cure (registered trademark) DICY7” (Mitsubishi Chemical Co., Ltd., dicyandiamide finely pulverized product): 4 parts by mass, “jER Cure (registered trademark) EMI24” (Mitsubishi Chemical Co., Ltd., imidazole curing agent) 1 part by mass, 100 parts by mass of methyl ethyl ketone, and 100 parts by mass of cyclohexanone were mixed to prepare an adhesive composition.
Next, as a metal support, 0.23 mm tin-free steel (manufactured by JFE Steel Co., Ltd., a metal plate treated with metal chromium, chromium hydrated oxide, and oil film on the surface of the ground iron in this order, hereinafter abbreviated as “TFS”. And the adhesive composition was applied to a thickness of 0.30 mm with a doctor blade, and then dried under a drying condition of 95 ° C. for 2 minutes to evaporate the solvent component. Further, 160 ° C., 1.5 Baking treatment was performed under time conditions to obtain a processed metal support on which an adhesive layer having a thickness of 6 to 8 μm was formed.
After applying a cellophane tape to protect a part of the surface of the adhesive layer of the obtained processed metal support, a suitable amount of photosensitive resin composition A (uncured treatment) is applied using 1 mm thick rubber as a spacer. Then, “APR (registered trademark) base film type BF-444” (polyethylene film treated with an adhesive for urethane-based liquid photosensitive cured product) was laminated thereon to produce a photosensitive resin layer.
Here, the cellophane tape was applied to a part of the surface of the adhesive layer to protect it in order to produce a cured layer of the photosensitive resin composition that does not contact the adhesive layer in the adhesive strength measurement described later. Is.
The photosensitive resin laminate is compressed with two 5 mm-thick glass plates to adjust the thickness, and then the surface of the photosensitive resin composition A laminated with ultraviolet light is exposed to 1800 mJ / cm ² . The photosensitive resin composition A was photocured by irradiation in an amount to obtain a printing plate laminate for laser engraving in which the photosensitive layer for printing relief was photocured.

(Adhesive strength measurement)
The photocured product of the obtained printing plate laminate for laser engraving was cut out to a width of 1 cm, and the photocured product (cured product and adhesive layer of the photosensitive resin composition layer) in which the surface of the adhesive layer was covered with cellophane tape. Folded 180 degrees. Attach the folded metal support part and the cured part of the photosensitive resin composition layer to the upper and lower chucks of “Shimadzu Autograph AGS-X” (manufactured by Shimadzu Corporation) as a tensile tester. The peel test was conducted by separating at a speed of 50 mm / min, and the adhesive strength was measured.
At this time, after peeling occurred in the printing plate laminate for laser engraving, when the chuck was further separated by a length of 30 mm, the strength measurement value measured by the tensile tester was stable at 6.5 N / cm. . As a result of visually observing the peeled state of the peeled sample, the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition A.

  In Example 1, the photosensitive resin composition B was used instead of the photosensitive resin composition A, and the laser engraving printing plate laminate was manufactured under the same conditions as described above. The adhesive strength was 7.8 N / cm, and the release surface was the interface between the adhesive layer and the cured product layer of the photosensitive resin composition B.

[Example 2]
About the adhesive composition, the printing plate lamination for laser engraving was performed in the same manner as in [Example 1] except that 10 parts by mass of methylated melamine resin (trade name MS-11, manufactured by Sanwa Chemical Co., Ltd.) was further added. The body was manufactured.
When the photosensitive resin composition A was used, the adhesive strength was 12.5 N / cm, and the peeled surface was a cohesive failure of the cured layer of the photosensitive resin composition A.

In Example 2, using the photosensitive resin composition B instead of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
When the photosensitive resin composition B was used, the adhesive strength was 14.0 N / cm, and the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition B.

Example 3
The adhesive composition is changed to “trade name EPICLON850” (made by DIC Corporation, epoxy equivalent of about 188 g / eq, hereinafter abbreviated as “epoxy resin 850”), which is an epoxy-based thermosetting resin, and methylated melamine resin. 20 parts by mass of a certain “trade name SUPER BECKAMINE L-105-60” (manufactured by Sanwa Chemical, DIC Corporation) is added, and “jER Cure (registered trademark) DICY7” (manufactured by Mitsubishi Chemical Corporation, dicyandiamide finely pulverized product): 4 masses A printing plate laminate for laser engraving was produced in the same manner as in [Example 1] except that the amount was changed from 5 parts to 5 parts by weight.
When the photosensitive resin composition A was used, the adhesive strength was 11.0 N / cm, and the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition A.

In Example 3 described above, a photosensitive resin composition B was used in place of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
When the photosensitive resin composition B was used, the adhesive strength was 10.5 N / cm, and the peeled surface was a cohesive failure of the cured layer of the photosensitive resin composition B.

Example 4
About the adhesive composition, the printing plate laminated body for laser engraving was manufactured by the method similar to the said [Example 1] except having added 30 mass parts of butylated melamine resin "brand name SUPERBECKAMINE L-117-60".
When the photosensitive resin composition A was used, the adhesive strength was 13.7 N / cm, and the peeled surface was cohesive failure of the cured product layer of the photosensitive resin composition A.

In Example 4, a printing plate laminate for laser engraving was produced using the photosensitive resin composition B instead of the photosensitive resin composition A under the same conditions, and a peel test was performed in the same manner.
When the photosensitive resin composition B was used, the adhesive strength was 11.2 N / cm, and the peeled surface was cohesive failure of the cured product layer of the photosensitive resin composition B.

Example 5
In place of the adhesive composition of Example 1, a urethane-based thermosetting resin “TOMOFLEX (trademark) AD-502 grade” (polyester resin, ethyl acetate 50 mass% solution, hereinafter referred to as “AD-502”) Abbreviated.): 100 parts by mass, “TOMOFLEX ™ CAT-10L grade” (aromatic polyisocyanate, 50% by mass ethyl acetate solution, hereinafter abbreviated as “CAT-10L”): 10 parts by mass, methyl ethyl ketone: A photosensitive resin laminate was prepared in the same manner as in Example 1 except that 80 parts by mass and cyclohexanone: 80 parts by mass, and the adhesive strength was measured.
When the photosensitive resin composition A was used, the adhesive strength was 4.5 N / cm, and the peeled surface was an interface failure between the adhesive layer and the cured layer of the photosensitive resin composition A.

In Example 5, using the photosensitive resin composition B instead of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
The adhesive strength in the case of using the photosensitive resin composition B was 6.2 N / cm, and the peeled surface was an interface fracture between the adhesive layer and the cured layer of the photosensitive resin composition B.

Example 6
Regarding the adhesive composition, a printing plate laminate for laser engraving was prepared in the same manner as in [Example 5], except that 10 parts by mass of a methylated melamine resin (trade name MS-11, manufactured by Sanwa Chemical Co., Ltd.) was further added. The body was manufactured and the adhesive strength was measured.
When the photosensitive resin composition A was used, the adhesive strength was 7.2 N / cm, and the peeled surface was an interface failure between the adhesive layer and the cured layer of the photosensitive resin composition A.

In Example 6, using the photosensitive resin composition B instead of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
When the photosensitive resin composition B was used, the adhesive strength was 8.5 N / cm, and the peeled surface was an interface failure between the adhesive layer and the cured layer of the photosensitive resin composition B.

Example 7
Instead of the adhesive composition of Example 1, "jER (registered trademark) resin 828" (Mitsubishi Chemical Corporation, molecular weight: about 370, epoxy equivalent: 184 to 194 g / eq, below), which is an epoxy thermosetting resin (Abbreviated as “epoxy resin 828”): 33 parts by mass, “jER Cure (registered trademark) DICY7” (manufactured by Mitsubishi Chemical Corporation, dicyandiamide finely pulverized product): 5 parts by mass, “jER cure (registered trademark) EMI24” ( Mitsubishi Chemical Co., Ltd., imidazole-based curing agent): 1 part by mass, “SOLBIN (registered trademark) CNL grade” as a polyvinyl resin (manufactured by Nissin Chemical Industry Co., Ltd., vinyl chloride vinyl acetate copolymer resin, 90% by mass vinyl chloride / 10% by mass of vinyl acetate, number average molecular weight of 13,000 by GPC measurement, hereinafter abbreviated as “polyvinyl resin CNL”): 67 parts by mass, methyl ethyl Ketone: 100 parts by weight of cyclohexanone 100 parts by weight were mixed and the adhesive composition. For other conditions, a printing plate laminate for laser engraving was produced in the same manner as in [Example 1], and the adhesive strength was measured.
When the photosensitive resin composition A was used, the adhesive strength was 32.5 N / cm, and the peeled surface was a cohesive failure of the cured layer of the photosensitive resin composition A.

In Example 7, a printing plate laminate for laser engraving was produced using the photosensitive resin composition B in place of the photosensitive resin composition A under the same conditions, and a peel test was performed in the same manner.
In the peeling test, peeling did not occur after the start of measurement, and the cured product layer of the photosensitive resin composition B was torn off at the 180-degree folded portion, making it impossible to measure the adhesive strength.
From this, it was judged that the adhesive strength between the metal support and the adhesive layer, and between the adhesive layer and the cured layer of the photosensitive resin composition B was very strong.
Hereinafter, when the same result was obtained, it was simply described as “unpeelable”.

Example 8
About the adhesive composition of Example 7, it replaced with polyvinyl resin CNL and replaced with polyvinyl resin CNL "SOLBIN (registered trademark) CL grade" (manufactured by Nissin Chemical Industry Co., Ltd., vinyl chloride vinyl acetate copolymer resin, chloride) Printing plate lamination for laser engraving in the same manner as in Example 7 except that 86% by mass vinyl / 14% by mass vinyl acetate, number average molecular weight 19000 by GPC measurement, and abbreviated as “polyvinyl resin CL”) A body was prepared and the adhesive strength was measured.
When the photosensitive resin composition A was used, the adhesive strength was 31.5 N / cm, and the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition A.

In Example 8 described above, the photosensitive resin composition B was used in place of the photosensitive resin composition A, and a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
The result of the peel test was “non-peelable”, and it was judged that the adhesive strength between the metal support and the adhesive layer, and between the adhesive layer and the cured product layer of the photosensitive resin composition B was very strong.

Example 9
About the adhesive composition of Example 7, “SOLBIN (registered trademark) M5 grade” (manufactured by Nissin Chemical Industry Co., Ltd., vinyl chloride vinyl acetate copolymer resin, 85% by mass of vinyl chloride / vinyl acetate, instead of polyvinyl resin CNL) The printing plate laminate for laser engraving was prepared in the same manner as in Example 7, except that 14 mass% / dicarboxylic acid 1 mass%, GPC measurement number average molecular weight 32000, hereinafter abbreviated as “polyvinyl resin M5”). Prepared and measured the adhesive strength.
When the photosensitive resin composition A was used, the adhesive strength was 31.5 N / cm, and the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition A.

In Example 9, a printing plate laminate for laser engraving was produced using the photosensitive resin composition B instead of the photosensitive resin composition A under the same conditions, and a peel test was performed in the same manner.
The result of the peeling test using the photosensitive resin composition B is “unpeelable”, and the adhesive strength between the metal support and the adhesive layer, and the adhesive layer and the cured layer of the photosensitive resin composition B. Could be judged to be very strong.

Example 10
For the adhesive composition of Example 7, “SOLBIN (registered trademark) C5R grade” (manufactured by Nissin Chemical Industry Co., Ltd., vinyl chloride vinyl acetate copolymer resin, 79% by mass of vinyl chloride / vinyl acetate, instead of polyvinyl resin CNL) A printing plate laminate for laser engraving was prepared in the same manner as in Example 7 except that 21% by mass, GPC measurement number average molecular weight 20000, hereinafter abbreviated as “polyvinyl resin C5R”. It was measured.
When the photosensitive resin composition A was used, the adhesive strength was 31.5 N / cm, and the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition A.

In Example 10, using the photosensitive resin composition B instead of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
The result of the peeling test using the photosensitive resin composition B is “unpeelable”, and the adhesive strength between the metal support and the adhesive layer, and the adhesive layer and the cured layer of the photosensitive resin composition B. Could be judged to be very strong.

Example 11
For the adhesive composition of Example 5, “AD-502” was changed from 100 parts by mass to 50 parts by mass, and a polyvinyl resin “Kanevinyl (registered trademark) S-400 grade” (manufactured by Kaneka Corporation, vinyl chloride). A printing plate laminate for laser engraving was prepared in the same manner as in Example 5 except that a resin, a number average molecular weight of 22000 by GPC measurement, and abbreviated as “polyvinyl resin S-400” is used. Was measured.
When the photosensitive resin composition A was used, the adhesive strength was 25.5 N / cm, and the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition A.

In Example 11, using the photosensitive resin composition B instead of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
The result of the peeling test using the photosensitive resin composition B is “unpeelable”, and the adhesive strength between the metal support and the adhesive layer, and the adhesive layer and the cured layer of the photosensitive resin composition B. Could be judged to be very strong.

Example 12
About the adhesive composition of Example 7, the polyvinyl resin CNL is replaced by 67 parts by mass to 12 parts by mass, and “jER (registered trademark) resin 1001” (Mitsubishi Chemical Co., Ltd., molecular weight), which is an epoxy thermosetting resin. : About 900, epoxy equivalent: 450 to 500 g / eq, hereinafter abbreviated as “epoxy resin 1001”.): A printing plate laminate for laser engraving was prepared in the same manner as in Example 7 except that 55 parts by mass were further added. Prepared and measured the adhesive strength.
When the photosensitive resin composition A was used, the adhesive strength was 30.4 N / cm, and the peeled surface was a cohesive failure of the cured layer of the photosensitive resin composition A.

In Example 12, using the photosensitive resin composition B instead of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
The result of the peel test when using the photosensitive resin composition B was 12.2 N / cm, and the peeled surface was a cohesive failure of the cured product layer of the photosensitive resin composition B.

[Comparative Example 1]
Instead of the metal support of [Example 1], a 0.20 mm tin steel plate (manufactured by Nippon Steel & Sumitomo Metal) was used. In addition, regarding the adhesive composition, instead of “epoxy resin 834”, “jER cure (registered trademark) DICY7”, and “jER cure (registered trademark) EMI24”, a polyvinyl resin “SOLBIN (registered trademark CNL grade)” 100 parts by mass of a vinyl chloride vinyl acetate copolymer resin manufactured by Shin Chemical Industry Co., Ltd. was used.
Other conditions were the same as in [Example 1], a printing plate laminate for laser engraving was produced, a peel test was performed, and the adhesive strength was measured.
When the photosensitive resin composition A was used, the adhesive strength could not be measured. When the peeled surface was observed, interface destruction between the adhesive layer and the cured product layer of the photosensitive resin composition A was confirmed.

In Comparative Example 1, a photosensitive resin composition B was used in place of the photosensitive resin composition A, a printing plate laminate for laser engraving was produced under the same conditions, and a peel test was performed in the same manner.
When the photosensitive resin composition B was used, it peeled off immediately and the adhesive strength could not be measured. When the peeled surface was observed, interface destruction between the adhesive layer and the cured product layer of the photosensitive resin composition B was confirmed.

  Tables 1 and 2 show the conditions and results of each example and each comparative example.

As shown in Table 1, it was confirmed that Examples 1 and 2 have excellent adhesive strength.
Furthermore, it was confirmed that all of the examples were able to stably exhibit excellent adhesive strength.

  The printing plate laminate for laser engraving of the present invention is industrially used in various fields including general printing plate materials, dry offset plate materials, metal foil printing plate materials, master mold plate materials, and embossing plate materials. There is a possibility to use on.

Claims (4)

A metal support;
An adhesive layer laminated on the surface of the metal support;
A photosensitive layer for printing relief laminated on the surface of the adhesive layer;
And having
The adhesive layer is a cured product made of a composition containing a thermosetting resin,
The photosensitive layer for printing relief includes an unsaturated polyurethane prepolymer, an ethylenically unsaturated compound, and a photopolymerization initiator,
A printing plate laminate for laser engraving in which the photosensitive layer for printing relief is cured.   The printing plate laminate for laser engraving according to claim 1, wherein the thermosetting resin is an epoxy resin or a urethane resin.   The printing plate laminate for laser engraving according to claim 1, wherein the thermosetting resin contains an amino resin.   The laser engraving according to any one of claims 1 to 3, wherein the unsaturated polyurethane prepolymer includes a polyester polyol and / or a polycarbonate polyol as a polymerization monomer and has a number average molecular weight of 1,000 to 100,000. Printing plate laminate.