JP5116623B2 - Cylindrical printing master forming equipment - Google Patents

Description

  The present invention relates to a cylindrical printing original plate forming apparatus that adheres a sheet-like resin onto a cylindrical support using laser light.

In recent years, when manufacturing resin relief printing such as flexographic printing, dry offset printing, and letter press printing, or when performing surface processing such as embossing, the resin portion irradiated with laser light is irradiated on the resin layer surface. A laser engraving method for forming a concavo-convex pattern on the surface by being removed has come to be used.
The printing plate material applied to the laser engraving method includes vulcanized rubber, a cured photosensitive resin obtained by photocuring a photosensitive resin composition, and a heat obtained by thermosetting a thermosetting resin composition. A curable resin cured product is used. In particular, in recent years, a technique for laser engraving a cured photosensitive resin has been increasing from the viewpoint of shortening the processing time.

  Patent Document 1 describes a method of bonding two sheet-shaped resins. Patent Document 1 describes a method of bonding the end portions of two sheet-like resins.

International Publication No. 2005/021245 Pamphlet

However, Patent Document 1 does not describe any method for adhering a sheet-like resin on a cylindrical support.
A device for adhering a sheet-like resin on a cylindrical support requires a completely different mechanism from an apparatus for adhering two sheet-like resins. Moreover, it is required to produce a cylindrical object by adhering a sheet-like resin on a cylindrical support while ensuring thickness accuracy. In particular, in the printing technology field, it is extremely important to ensure the plate thickness accuracy.

There has been a strong demand for an apparatus for manufacturing a cylindrical printing original plate with high productivity and high thickness accuracy by adhering a sheet-like resin on a cylindrical support, but such an apparatus exists in the prior art. It wasn't.
The problem to be solved by the present invention is to provide a cylindrical printing original plate forming apparatus for producing a cylindrical printing original plate with high productivity and high thickness accuracy by adhering a sheet-like resin on a cylindrical support. It is in.

  As a result of intensive studies to solve the above problems, the inventors of the present invention are cylindrical printing original plate forming apparatuses for adhering a sheet-like resin on a cylindrical support (a), and (1) the cylindrical shape A mechanism for holding the support (a) and rotating it in the circumferential direction; and (2) holding a laser beam transmitting plate-like object or cylindrical object, and spacing between the cylindrical support (a) and the surface. A mechanism for changing; (3) a laser light source; and (4) the sheet-like resin is sandwiched between the plate-like object or cylindrical object and the cylindrical support (a), and the plate-like object or cylindrical object. And an optical system for irradiating laser light onto the interface between the sheet-like resin and the cylindrical support (a) that absorbs laser light, and (5) the position where the laser light is irradiated is cylindrical. A mechanism for moving the support (a) in the long axis direction, It can solve the serial problems, and have completed the present invention.

The present invention is as follows.
1.
A cylindrical printing original plate molding apparatus for adhering a sheet-like resin on a cylindrical support (a),
(1) a mechanism for holding the cylindrical support (a) and rotating it in the circumferential direction;
(2) a mechanism for holding a laser light-transmitting plate or cylinder and changing the distance from the surface of the cylindrical support (a);
(3) a laser light source disposed in the mechanism (2);
(4) The sheet resin is sandwiched between the plate or cylinder and the cylindrical support (a), and the sheet resin and laser light are absorbed through the plate or cylinder. An optical system for irradiating a laser beam on the interface with the cylindrical support (a);
(5) A cylindrical printing original plate forming apparatus comprising: a mechanism for moving a position irradiated with laser light in a long axis direction of the cylindrical support (a).
2.
The laser light source is a light source that emits laser light having a wavelength of 700 nm to 3 μm. The cylindrical printing original plate forming apparatus described in 1.
3.
The cylindrical support (a) is a hollow cylindrical support made of fiber reinforced plastic or metal,
The mechanism (1) has a cylindrical body made of at least one material selected from the group consisting of metal, rubber, and plastic. Or 2. The cylindrical printing original plate forming apparatus described in 1.
4).
The optical system (4) has a condensing lens and a mechanism for changing the distance between the condensing lens and the surface of the cylindrical support (a). To 3. The cylindrical printing original plate forming apparatus of any one of these.
5.
The mechanism (5) has a mechanism for changing the position of the optical system (4) in the long axis direction, or a mechanism for scanning laser light in the long axis direction. To 4. The cylindrical printing original plate forming apparatus of any one of these.
6).
The laser beam is pulsed, the frequency of the pulse is 1 kHz or more and 500 MHz or less, the pulse time half width is 1 nanosecond or more and 50 milliseconds or less, and the average output is 0.1 W or more and 200 W or less, 1. To 5. The cylindrical printing original plate forming apparatus of any one of these.
7).
The material of the plate or cylinder is at least one material selected from the group consisting of glass and plastic, and the light transmittance at the wavelength of the laser beam to be used is 50% or more and 100% or less. 1. To 6. The cylindrical printing original plate forming apparatus of any one of these.
8).
The cylindrical support (a) and the plate-like object or cylindrical object move synchronously,
1. The cylindrical support (a) and the sheet-like resin have a part in constant contact, and the contacted part is irradiated with laser light. To 7. The cylindrical printing original plate forming apparatus of any one of these.
9.
The sheet-like resin is made of at least one material selected from the group consisting of a thermoplastic resin, a photosensitive resin composition, and a thermosetting resin composition. To 8. The cylindrical printing original plate forming apparatus according to any one of the above.
10.
8. The sheet-like resin is a sheet-like laminate in which a photosensitive resin cured product or a thermosetting resin cured product is laminated on a sheet-like support made of the thermoplastic resin. The cylindrical printing original plate forming apparatus described in 1.
11.
The photosensitive resin composition or the thermosetting resin composition is polyamide, polyimide, polyurethane, polyester, polycarbonate, polyether polyol, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, and styrene. -Containing at least one resin selected from the group consisting of isoprene copolymers; The cylindrical printing original plate forming apparatus described in 1.
12
1. An apparatus for producing a cylindrical printing plate or a cylindrical printing plate used in flexographic printing, dry offset printing, or gravure printing applications. To 11. The cylindrical printing original plate forming apparatus of any one of these.
13.
11. The cylindrical printing original plate is a cylindrical printing original plate for laser engraving for forming a pattern on the surface by laser engraving. The cylindrical printing original plate forming apparatus described in 1.

  ADVANTAGE OF THE INVENTION According to this invention, the sheet form resin can be adhere | attached on a cylindrical support body, and the cylindrical printing original plate shaping | molding apparatus for manufacturing a cylindrical printing original plate with high productivity and highly accurate thickness can be provided.

  Hereinafter, the best mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

[Outline of cylindrical printing plate forming equipment]
The cylindrical printing original plate forming apparatus of the present embodiment is an apparatus for adhering a sheet-like resin on a cylindrical support (a),
(1) a mechanism for holding the cylindrical support (a) and rotating it in the circumferential direction;
(2) a mechanism for holding a laser light-transmitting plate or cylinder and changing the distance from the surface of the cylindrical support (a);
(3) a laser light source disposed in the mechanism (2);
(4) The sheet resin is sandwiched between the plate or cylinder and the cylindrical support (a), and the sheet resin and laser light are absorbed through the plate or cylinder. An optical system for irradiating a laser beam on the interface with the cylindrical support (a);
(5) A cylindrical printing original plate forming apparatus comprising: a mechanism for moving a position irradiated with laser light in a long axis direction of the cylindrical support (a).

  The cylindrical printing original plate molding is a device for adhering both by installing a sheet-like resin on the cylindrical support (a) and thermally welding it by irradiating the interface with laser light.

As the mechanism (1) for holding the cylindrical support (a) and rotating it in the circumferential direction, it is preferable to have a cylindrical object made of at least one material selected from the group consisting of metal, rubber and plastic.
Examples of the cylindrical member include an air cylinder and a jig such as an air shaft having a mechanism for changing the outer diameter of the cylinder when the cylindrical support (a) is a hollow cylindrical support. The cylindrical support (a) is held using the jig. The jig preferably has a shaft for rotating the hollow cylindrical support in the circumferential direction, and preferably holds the shaft and rotates the hollow cylindrical support in the circumferential direction.
It is preferable that the jig has a shaft portion such as a journal, and the cylindrical printing original plate forming apparatus includes a rotation mechanism for holding and rotating the shaft portion. An example of the rotating mechanism is a stepping motor having an encoder in order to ensure positional accuracy.

From the viewpoint of ensuring the thickness accuracy of the cylindrical printing original plate, the cylindrical support forming apparatus holds a laser beam-transmitting plate-like object or cylindrical object, and sets an interval with the surface of the cylindrical support (a). A mechanism (2) for changing is provided.
The mechanism (2) changes the distance between the plate-shaped object or the cylindrical object and the surface of the cylindrical support (a) so that the cylindrical support (a) and the sheet-shaped resin are in contact with each other. This is a mechanism in which the sheet-like resin is sandwiched between the article or the cylindrical article and the cylindrical support (a). Moreover, the mechanism which can change the distance between a cylindrical support body (a) and a plate-shaped object or a cylindrical object from a viewpoint of workability | operativity is provided.

The outer diameter of the cylindrical support (a) to be used and the thickness of the sheet-like resin need to be changed depending on the use and the repeat length of the printed matter. Depending on the outer diameter of the cylindrical support (a) and the thickness of the sheet-like resin, the distance between the surface of the cylindrical support (a) and the plate or cylindrical object can be changed by the mechanism (2). preferable.
When joining the two by laser welding, it is necessary to keep the distance between the surface of the cylindrical support (a) and the sheet-like resin constant, so a stepping motor, servo motor, It is preferable to enable fine adjustment using a linear motor or the like.
In changing the distance between the surface of the cylindrical support (a) and the sheet-like resin, the cylindrical support (a) side may be moved, or the plate or cylindrical object may be moved.

The laser beam transmitting plate or cylinder has a light transmittance of preferably 50% or more and 100% or less, more preferably 70% or more and 100% or less, at the wavelength of the laser beam used. More preferably, it is 80% or more and 100% or less.
If the light transmittance of the plate or cylinder is within the above range, the laser beam energy absorbed by the plate or cylinder is small, and the laser beam can be efficiently used for bonding.

The cylindrical object is preferably a hollow cylinder. The thickness of the plate-like object or cylindrical object is preferably 0.1 mm or more and 50 mm or less, more preferably 0.5 mm or more and 10 mm or less, and further preferably 1 mm or more and 5 mm or less.
If the thickness of the plate-like object or the cylindrical object is within the above range, the mechanical strength can be sufficiently secured, and the plate-like object or the cylindrical object can be used without being excessively heavy. The material of the plate or cylinder is preferably glass or plastic.
When near infrared laser light is used as the laser light, it is more preferable to use a plastic with little light absorption from the viewpoint of weight reduction.

Although the laser light source (3) arrange | positioned in a mechanism (2) is not specifically limited, A cylindrical support body (a) and sheet-like resin can be adhere | attached.
In order for the surface of the cylindrical support (a) to absorb the laser beam and convert the light into heat, a near-infrared or infrared region laser beam having a wavelength of 700 nm or more is preferable. Among these, a laser beam in the near infrared region having a wavelength of 3 μm or less is preferable from the viewpoint of the light absorption characteristics of the plate or cylinder.

Examples of the laser light source include a semiconductor laser, a YAG laser, a YVO ₄ laser, a fiber laser doped with Er or Yb, a Ti sapphire laser, and an alexandrite laser. The laser light may be continuous wave laser light or pulsed laser light.

  The average output of the laser light source is preferably from 0.1 W to 200 W, more preferably from 0.5 W to 100 W, and even more preferably from 1 W to 100 W.

Pulse oscillation laser light is preferred from the viewpoint that the peak output is large even when the average output of the laser light source is relatively small and can be used in the bonding step.
The pulse time half-width of the pulsed laser beam is preferably 1 nanosecond or more and 50 milliseconds or less, more preferably 5 nanoseconds or more and 1 millisecond or less, and further preferably 10 nanoseconds or more and 50 microseconds or less. It is.
If the half-width of the pulse time of the pulsed laser beam is within the above range, it can be sufficiently used in the bonding step without using a high-power laser beam.
The oscillation frequency of the pulsed laser beam is preferably 1 kHz to 500 MHz, more preferably 10 kHz to 100 MHz.
If the oscillation frequency of the pulsed laser beam is within the above range, a pulse having a sufficiently high peak output can be used in the bonding step.

  The laser beam diameter irradiated to the contact interface between the cylindrical support (a) and the sheet-like resin is preferably 1 μm or more and 5 mm or less because the laser beam can be reduced to a small diameter using a condenser lens. More preferably, it is 10 μm or more and 4 mm or less, and further preferably 0.1 mm or more and 3 mm or less.

  The beam diameter at the focal point of the laser beam (α) is preferably 1 μm or more and 5 mm or less, more preferably 0.1 mm or more and 4 mm or less, and even more preferably 0.1 mm from the viewpoint of improving the bonding speed. It is 3 mm or less.

The cylindrical printing original plate forming apparatus sandwiches a sheet-shaped resin between a plate-shaped object or a cylindrical object and a cylindrical support (a), and absorbs the sheet-shaped resin and the laser beam through the plate-shaped object or the cylindrical object. An optical system (4) for irradiating a laser beam is provided at the interface with the cylindrical support (a).
The optical system (4) preferably has a condensing lens and has a mechanism for changing the distance between the condensing lens and the surface of the cylindrical support (a). The optical system (4) may be disposed in the laser light source or may be installed on the surface of the laser light source.
The cylindrical printing original plate forming apparatus may have a laser head in which a condenser lens and a laser light source are disposed.

The laser beam can be narrowed down to a small diameter using a condenser lens.
It is preferable to focus the laser beam in the vicinity of the contact interface between the cylindrical support (a) and the sheet-like resin using a condensing lens. A distance between the surface of the cylindrical support (a) and the condenser lens by a mechanism for changing the distance of the condenser lens of the optical system (4) or a mechanism for changing the position of the cylindrical support (a). Is preferably controlled.

Since it is preferable that there are a plurality of locations where the cylindrical support (a) and the sheet-like resin are bonded, the cylindrical printing original plate forming apparatus determines the position where the laser beam is irradiated as the length of the cylindrical support (a). A mechanism (5) for moving in the axial direction is provided.
As the mechanism (5), the condensing lens is generally disposed at the end of the optical system. Therefore, as the mechanism (5), the position of the optical system (4) such as the condensing lens is set to a cylindrical support. (A) a mechanism for moving the laser beam in the long axis direction, a mechanism for scanning the laser beam in the long axis direction, specifically, a mechanism for disposing a galvanometer mirror or a polygon mirror for scanning the laser beam in front of the condenser lens Etc.
The laser beam does not need to be moved along the major axis accurately, and may be moved in the major axis direction.

  The cylindrical support (a) can be rotated to change the position where the laser beam is irradiated in the circumferential direction. The part irradiated with the laser light may be carried out without a gap in the cylindrical surface or may be carried out with a short gap.

The mechanism (5) can irradiate the cylindrical support (a) with a laser beam in the longitudinal direction of the cylindrical support (a) to bond the cylindrical support (a) and the sheet-like resin. By rotating in the circumferential direction according to 1), the position of the cylindrical support (a) to be irradiated with the laser can be changed, and the cylindrical support (a) and the sheet-like resin can be bonded.
By bonding in this way, the entire sheet-like resin can be bonded. In addition, the time required for the bonding process can be shortened by bonding at intervals.

In the present embodiment, it is preferable that the laser light-transmitting plate or cylinder and the cylindrical support (a) move synchronously. Since the cylindrical support (a) and the sheet-shaped resin can always be brought into contact with each other by moving both in synchronization, a void is formed between the cylindrical support (a) and the sheet-shaped resin. Can be prevented.
In the present embodiment, it is preferable that the cylindrical support (a) and the sheet-like resin have a part in constant contact, and the contacted part is irradiated with laser light. Since the cylindrical resin (a) and the sheet resin are always in contact, the sheet resin can be bonded onto the cylindrical support with high thickness accuracy.

  By using the cylindrical printing original plate forming apparatus of the present embodiment, a sheet-like resin can be bonded onto the cylindrical support (a). In the present embodiment, it is preferable to use a cylindrical support (a) and a sheet-like resin described below.

[Cylindrical support (a)]
Examples of the cylindrical support (a) include a metal, rubber, or plastic cylinder, and a hollow cylindrical support such as a metal, plastic, or fiber-reinforced plastic sleeve. From the viewpoint of weight and handling, a hollow cylindrical support is preferable.
Examples of the material constituting the metallic cylinder or the metallic sleeve include materials such as aluminum, nickel, and iron.
Examples of the material constituting the plastic cylinder or the plastic sleeve include materials such as polyester, polyimide, polyamide, polyphenylene ether, polyphenylene thioether, polysulfone, and epoxy resin.
Examples of the fiber material constituting the fiber reinforced plastic sleeve include materials such as polyester fiber, polyimide fiber, polyamide fiber, polyurethane fiber, cellulose fiber, glass fiber, metal fiber, ceramic fiber, and carbon fiber.
Examples of the material constituting the rubber cylinder include materials such as EPDM rubber, fluororubber, silicone rubber, urethane rubber, and SB rubber.

When the cylindrical support (a) is a hollow cylindrical support, the thickness of the hollow cylindrical support is preferably 0.2 mm or more and 2 mm or less. The thickness of the intermediate cylindrical support is more preferably 0.3 mm or more and 1.5 mm or less, and further preferably 0.4 mm or more and 1 mm or less.
If the thickness of the hollow cylindrical support is within the above range, it can be easily mounted on the mechanism (1), and sufficient mechanical strength can be ensured without being broken or cracked.

A laser light absorption layer is preferably laminated on the surface of the cylindrical support (a). The thickness of the laser light absorbing layer is preferably from 10 μm to 500 μm, more preferably from 50 μm to 300 μm, and even more preferably from 80 μm to 200 μm.
The laser light absorbing layer preferably contains a dye or pigment that absorbs the laser light to be used. It is preferable that a component similar to the component of the sheet-like resin to be laminated is contained. Dyes and pigments that absorb laser light are not particularly limited, but black pigments such as carbon black, graphite, activated carbon, carbon nanotubes, and fullerenes, metal oxide pigments such as iron oxide and copper oxide, and phthalocyanine And organic pigments and dyes.

"Heat-shrinkable tube"
A laser light absorption layer can also be formed using a heat-shrinkable tube.
As a heat-shrinkable tube, it is a heat-shrinkable tube that has both the property of shrinking when heated and the property of absorbing laser light.
Regarding the shrinkage characteristics of the heat-shrinkable tube, the heat shrinkage rate at 80 ° C. is preferably 10% or more and 50% or less. More preferably, they are 20% or more and 50% or less, More preferably, they are 20% or more and 40% or less.
If the thermal contraction rate is within the above range, it can be securely fixed to the cylindrical support (a), can be prevented from shifting in the circumferential direction even in the printing process, and sufficient mechanical strength can be secured. is there.

The thickness of the heat-shrinkable tube is preferably 10 μm or more and 500 μm or less, more preferably 25 μm or more and 250 μm or less, and further preferably 50 μm or more and 150 μm or less.
If the thickness of the heat-shrinkable tube is within the above range, the tube can be easily formed, and sufficient mechanical strength can be ensured.

Since the laser light is applied to the contact interface between the heat-shrinkable tube and the sheet-like resin, the heat-shrinkable tube needs to absorb the laser light used for welding.
The heat-shrinkable tube preferably contains a laser light absorber in order to absorb laser light. Since laser light having an oscillation wavelength in the near infrared region is preferable as the laser light, the laser light absorbent preferably contains a dye or pigment having light absorption characteristics in the near infrared region.

  Preferred compounds as laser light absorbers include black pigments such as carbon black, graphite, activated carbon, carbon nanotubes, fullerenes, organic dyes and organic pigments such as phthalocyanine, azo, perinone, and anthraquinone, iron oxide, oxidation Inorganic pigments such as metal oxides such as copper, chromates, sulfides, silicates, carbonates and ferrocyanides can be mentioned.

The light transmittance of the heat-shrinkable tube is preferably 10% or less, more preferably 1% or less, and even more preferably 0.1% or less, at the wavelength of the laser light used.
If the light transmittance of the heat-shrinkable tube is within the above range, the laser beam can be sufficiently absorbed.

  The heat-shrinkable tube may be a tube in which both ends of the film are welded or a seamless tube without a joint. In the case of forming both ends of the film by welding, the film can be produced by molding using a technique such as extrusion molding or casting, and then stretching. Moreover, a seamless tube can be produced by inflation using a circular die or a ring die.

  Examples of the material for the heat-shrinkable tube include materials such as polyolefin, polyester, polystyrene, polyamide, and polyvinyl acetate.

  The surface roughness of the heat-shrinkable tube is preferably 0.5 μm or less from the viewpoint of ensuring adhesive strength with the cylindrical support and ensuring surface flatness.

[Sheet resin]
The sheet-like resin is preferably made of at least one material selected from the group consisting of a thermoplastic resin, a photosensitive resin composition, and a thermosetting resin composition.
As a sheet-like resin, a photosensitive resin cured product or a thermosetting resin cured product on a sheet-like support made of a thermoplastic resin from the viewpoints of laser engraving property, image formability, flexibility, mechanical strength securing, etc. It is preferable that it is a sheet-like laminated body with which is laminated | stacked.

In the present embodiment, the cured photosensitive resin is a cured resin obtained by photocuring the photosensitive resin composition, and the cured thermosetting resin is obtained by thermosetting the thermosetting resin composition. (Hereinafter simply referred to as “photosensitive resin composition and thermosetting resin composition”, “resin composition”, “photosensitive resin cured product and thermosetting resin cured product”, “resin curing”) May be described as "thing").
The resin composition is selected from the group consisting of polyamide, polyimide, polyurethane, polyester, polycarbonate, polyether polyol, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, and styrene-isoprene copolymer. It is preferable to contain at least one kind of resin.

When the cylindrical printing original plate is for flexographic printing, the resin composition may be a polyurethane having a relatively low hardness, such as polyurethane, polyester, polycarbonate, polyether polyol, styrene-butadiene copolymer, and styrene-isoprene copolymer. It is preferable to contain a material.
When the cylindrical printing original plate is for dry offset printing or gravure printing, the resin composition is made of a material such as polyamide, polyimide, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, and polycarbonate having a relatively high hardness. It is preferable to contain.

The sheet-like support preferably has a thickness of 10 μm or more and 500 μm or less from the viewpoints of dimensional stability, lightness, flexibility, and flatness. The thickness of the sheet-like support is more preferably from 50 μm to 300 μm, still more preferably from 50 μm to 200 μm.
Examples of the material for the sheet-like support include metals such as nickel, aluminum, and iron, and a thermoplastic resin that is at least one selected from the group consisting of polyester, polyamide, and polyimide.

  The sheet-like resin is preferably a material that transmits the laser beam to be used, and the light transmittance of the sheet-like resin at the wavelength of the laser beam to be used is preferably 50% or more and 100% or less, more preferably 70. % To 100%, more preferably 80% to 100%.

The thickness of the sheet-like resin is preferably from 0.1 mm to 5 mm.
If the thickness of the sheet-like resin is within this range, it can be used for printing applications such as flexographic printing, dry offset printing, and gravure printing.

  In the present embodiment, the resin composition forming the sheet-like resin preferably contains the resin (b) and the organic compound (c).

[Resin (b)]
The number average molecular weight of the resin (b) is preferably 1000 or more and 300,000 or less, more preferably 2000 or more and 200,000 or less, and further preferably 5000 or more and 150,000 or less.
If the number average molecular weight of the resin (b) is 1000 or more, the cured resin prepared by crosslinking later maintains strength and can withstand repeated use.
If the number average molecular weight of the resin (b) is 300,000 or less, the resin composition can be molded without excessively increasing the melt viscosity of the resin composition.
In the present embodiment, the number average molecular weight is a value measured by gel permeation chromatography, calibrated with polystyrene having a known molecular weight, and converted.

The resin (b) may have a polymerizable unsaturated group in the molecule.
Preferred examples of the resin (b) include compounds having an average of 0.7 or more polymerizable unsaturated groups per molecule.
If the average number of polymerizable unsaturated groups is 0.7 or more per molecule, the cured resin has excellent mechanical strength and good durability, and can withstand repeated use, particularly as a printing substrate. It is preferable.
From the viewpoint of the mechanical strength of the cured resin, the number of polymerizable unsaturated groups in the resin (b) is preferably 0.7 or more per molecule, more preferably 1 or more, more preferably 1 or more. 10 or less, more preferably 1 or more and 5 or less.
The upper limit of the number of polymerizable unsaturated groups per molecule of the resin (b) is not particularly limited, but the number of polymerizable unsaturated groups per molecule is preferably 20 or less. If the number of polymerizable unsaturated groups per molecule of the resin (b) is 20 or less, shrinkage during curing can be suppressed to a low level, and occurrence of cracks in the vicinity of the surface can also be suppressed.

  In the present embodiment, having a polymerizable unsaturated group in the molecule means that the polymerizable unsaturated group is directly contained in the end of the polymer main chain, the end of the polymer side chain, the polymer main chain, and the polymer side chain. The case where a saturated group is attached is also included.

Examples of the resin (b) include compounds having a polymerizable unsaturated group in the molecule with a polymer as shown below as a skeleton.
Examples of polymers include polyolefins such as polyethylene and polypropylene; polydienes such as polybutadiene and polyisoprene; polyhaloolefins such as polyvinyl chloride and polyvinylidene chloride; polystyrene, polyacrylonitrile, polyvinyl alcohol, polyvinyl acetate, polyvinyl acetal , Polymers having a hetero atom in the main chain such as polyacrylic acid, poly (meth) acrylic acid esters, poly (meth) acrylamide, polyester, polycarbonate, polyacetal, polyurethane, polyamide, polyurea, polyether polyol, and polyimide, One or two selected from the group consisting of vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer and the like It may be used or more polymers. When using a plurality of polymers, either a copolymer or a blend may be used.

When a flexible relief image is required as in flexographic printing plate applications, as part of the resin (b), a liquid resin having a glass transition temperature of 20 ° C. or lower, preferably a liquid resin having a glass transition temperature of 0 ° C. or lower. Can also be added.
Liquid resins include, for example, hydrocarbons such as polyethylene, polybutadiene, hydrogenated polybutadiene, polyisoprene, and hydrogenated poisoprene; polyesters such as adipate and polycaprolactone; polyethylene such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol Examples include ethers; aliphatic polycarbonates; silicones such as polydimethylsiloxane; polymers of (meth) acrylic acid and / or derivatives thereof, and mixtures and copolymers thereof.
The content of the liquid resin is preferably 30% by mass to 100% by mass with respect to the entire resin (b).
As the liquid resin, unsaturated polyurethanes having a polycarbonate structure are preferable from the viewpoint of weather resistance. Examples of the unsaturated polyurethane include a resin having a polymerizable unsaturated group such as an acrylate group or a methacrylate group at the end of the polyurethane molecular chain, and a resin having a double bond in the polyurethane molecular chain.

As a method of introducing a polymerizable unsaturated group into the molecule of the resin (b), for example, a method of directly polymerizing using a monomer having a polymerizable unsaturated group introduced into the molecular end or molecular chain thereof. Can be mentioned.
As another method, a method in which a resin (polymer) and a compound having a polymerizable unsaturated group are reacted to introduce a polymerizable unsaturated group into the terminal of the resin can also be mentioned. Specifically, it has a plurality of reactive groups such as a hydroxyl group, amino group, epoxy group, carboxyl group, acid anhydride group, ketone group, hydrazine residue, isocyanate group, isothiocyanate group, cyclic carbonate group, and ester group. The compound is allowed to react with a binder having a plurality of functional groups capable of binding to a reactive group (for example, when the reactive group is a hydroxyl group or an amino group, examples of the binder include polyisocyanate), and the molecular weight. The resin obtained by the reaction is reacted with a compound having a functional group capable of reacting with the terminal binding group of the resin and a polymerizable unsaturated group. Then, a polymerizable unsaturated group is introduced into the terminal of the resin.

When the cured resin is used as a printing substrate for laser engraving, it is preferable to use a polymer having high thermal decomposability as the resin (b). For example, polymers having α-methylstyrene, methacrylic acid ester, and acrylic acid ester units, or a carbonate bond and a carbamate bond in the molecule are known as highly thermally decomposable compounds.
As an index of thermal decomposability, thermogravimetric data obtained by measuring weight loss when a sample is heated in an inert gas atmosphere can be used.
The temperature at which the weight of the resin (b) is halved is preferably in the range of 150 ° C. or higher and 450 ° C. or lower. The temperature at which the weight of the resin (b) is halved is more preferably in the range of 250 ° C. or higher and 400 ° C. or lower, and still more preferably in the range of 250 ° C. or higher and 380 ° C. or lower.

  As the resin (b), a compound in which thermal decomposition occurs in a narrow temperature range is preferable. As an indicator that thermal decomposition occurs in a narrow temperature range, in thermogravimetric analysis, the difference between the temperature at which the weight is reduced to 80% of the initial weight and the temperature at which the weight is reduced to 20% of the initial weight is 100 ° C. or less. It is preferable that The temperature difference is more preferably 80 ° C. or less, and further preferably 60 ° C. or less.

[Organic compound (c)]
The organic compound (c) is a compound having a polymerizable unsaturated group involved in radical polymerization reaction or ring-opening polymerization reaction, and the number average molecular weight is 1000 or less in consideration of easiness of dilution with the resin (b). It is preferable that
Examples of the organic compound (c) include olefins such as ethylene, propylene, styrene and divinylbenzene; acetylenes; (meth) acrylic acid and derivatives thereof; haloolefins; unsaturated nitriles such as acrylonitrile; (meth) acrylamide Allyl compounds such as allyl alcohol and allyl isocyanate; unsaturated dicarboxylic acids such as maleic anhydride, maleic acid, fumaric acid, and itaconic acid and their derivatives; vinyl acetates; N-vinylpyrrolidone; Carbazole; cyanate esters and the like.
As the organic compound (b), derivatives such as (meth) acrylic acid and (meth) acrylic acid ester are preferable from the viewpoints of variety and price.

As the derivative, an alicyclic compound having a functional group such as a cycloalkyl group, a bicycloalkyl group, a cycloalkene group, and a bicycloalkene group ; a functional group such as a benzyl group, a phenyl group, a phenoxy group, a methylstyryl group, and a styryl group An aromatic compound having a group; an ester compound or an amide compound such as a compound having a functional group such as an alkyl group, a halogenated alkyl group, an alkoxyalkyl group, a hydroxyalkyl group, an aminoalkyl group, a tetrahydrofurfuryl group, and a glycidyl group; And ester compounds of polyhydric alcohols such as alkylene glycol, polyoxyalkylene glycol, (alkyl / allyloxy) polyalkylene glycol and trimethylolpropane.

  The organic compound (c) having a polymerizable unsaturated group can be selected from one or more compounds depending on the purpose. For example, when a cylindrical printing original plate is used as a printing plate, long-chain aliphatic, alicyclic, or aromatic is used as the organic compound (C) in order to suppress swelling with respect to an organic solvent such as alcohol or ester as a printing ink solvent. It is preferable to select at least one kind of group derivative.

  In order to increase the mechanical strength of the cured resin, it is preferable to select at least one compound having a substituent (functional group) such as an alicyclic group or an aromatic group as the organic compound (c). The compound having a substituent such as an alicyclic group or an aromatic group is preferably 20% by mass or more and 100% by mass or less, more preferably 50% by mass or more and 100% by mass with respect to the total amount of the organic compound (c). It is as follows.

  The sheet-like resin can be produced by photocuring the photosensitive resin composition. The photosensitive resin composition is irradiated with light and cured to form a laser engraving layer as a sheet-like resin.

[Photopolymerization initiator]
As light at the time of photocuring the photosensitive resin composition, high energy rays such as ultraviolet rays, visible rays, electron beams, and X-rays can be used.
When photocuring using ultraviolet rays or visible light, it is preferable to add a photopolymerization initiator to the photosensitive resin composition. Examples of the photopolymerization initiator include a hydrogen abstraction type photopolymerization initiator (d) and / or a decay type photopolymerization initiator (e).

[Hydrogen extraction type photopolymerization initiator (d)]
Although it does not specifically limit as a hydrogen abstraction type photoinitiator (d), An aromatic ketone can be mentioned.
An aromatic ketone is efficiently brought into an excited triplet state by photoexcitation. As this excited triplet state, a chemical reaction mechanism has been proposed in which hydrogen is extracted from the surrounding medium to generate radicals. The generated radical is considered to be involved in the photocrosslinking reaction.

The hydrogen abstraction type photopolymerization initiator (d) is not particularly limited as long as it is a compound that generates radicals by extracting hydrogen from a surrounding medium through an excited triplet state.
Examples of aromatic ketones include benzophenones, Michler ketones, xanthenes, thioxanthones, and anthraquinones, and it is preferable to use at least one compound selected from the group consisting of the aforementioned compounds.

Examples of benzophenones include benzophenone and derivatives thereof. Specifically, 3,3 ′, 4,4′-benzophenone tetracarboxylic anhydride, 3,3 ′, 4,4′-tetramethoxybenzophenone, etc. Can be mentioned.
Examples of Michler ketones include Michler ketone and derivatives thereof.
Examples of xanthenes include xanthene and derivatives substituted with an alkyl group, a phenyl group, or a halogen group.
Examples of thioxanthones include thioxanthone and derivatives substituted with an alkyl group, a phenyl group, and a halogen group. Specific examples include ethylthioxanthone, methylthioxanthone, and chlorothioxanthone.
Examples of anthraquinones include anthraquinone and derivatives substituted with an alkyl group, a phenyl group, or a halogen group.

The addition amount of the hydrogen abstraction type photopolymerization initiator (d) is preferably 0.3% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 5% by mass with respect to the total amount of the photosensitive resin composition. % Or less.
If the addition amount of the hydrogen abstraction type photopolymerization initiator (d) is within the above range, when the photosensitive resin composition is photocured in the atmosphere, the curability of the cured product surface can be sufficiently secured, and As a cured product, cracks and the like are not generated on the surface during long-term storage, and weather resistance can be ensured.

"Collapse photopolymerization initiator (e)"
The collapsible photopolymerization initiator (e) means a compound that generates an active radical by generating a cleavage reaction in the molecule after light absorption, and is not particularly limited.
Specifically, benzoin alkyl ethers, 2,2-dialkoxy-2-phenylacetophenones, acetophenones, acyloxime esters, azo compounds, organic sulfur compounds, acylphosphine oxides, diketones, etc. Can be mentioned.
As the collapsible photopolymerization initiator (e), it is preferable to use at least one compound selected from the group consisting of the aforementioned compounds.

Examples of benzoin alkyl ethers include benzoin isopropyl ether and benzoin isobutyl ether.
Examples of 2,2-dialkoxy-2-phenylacetophenones include 2,2-dimethoxy-2-phenylacetophenone and 2,2-diethoxy-2-phenylacetophenone.
Examples of acetophenones include acetophenone, trichloroacetophenone, 1-hydroxycyclohexylphenylacetophenone, and 2,2-diethoxyacetophenone.
Examples of acyloxime esters include 1-phenyl-1,2-propanedione-2- (o-benzoyl) oxime.
Examples of the azo compound include azobisisobutyronitrile, diazonium compound, and tetrazene compound.
Examples of diketones include benzyl and methylbenzoyl formate.

The addition amount of the collapsible photopolymerization initiator (e) is preferably 0.3% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 5% by mass based on the total amount of the photosensitive resin composition. It is as follows.
If the addition amount of the collapsible photopolymerization initiator (e) is within the above range, when the photosensitive resin composition is photocured in the air, the curability inside the cured product can be sufficiently secured. .

A compound having a site functioning as a hydrogen abstraction type photopolymerization initiator and a site functioning as a decay type photopolymerization initiator in the same molecule can also be used as the photopolymerization initiator.
Examples of the photoinitiator include α-aminoacetophenones.
Examples of α-aminoacetophenones include 2-methyl-1- (4-methylthiophenyl) -2-morpholino-propan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -Butanone etc. can be mentioned.

The addition amount of the photopolymerization initiator having a site functioning as a hydrogen abstraction type photopolymerization initiator and a site functioning as a decay type photopolymerization initiator in the same molecule is 0.3% by mass of the total amount of the photosensitive resin composition. The content is preferably 10% by mass or less, more preferably 0.5% by mass or more and 3% by mass or less.
If the addition amount of the photopolymerization initiator is within the above range, the mechanical properties of the cured product can be sufficiently ensured even when the photosensitive resin composition is photocured in the atmosphere.

  The sheet resin in the present embodiment may be a thermosetting resin composition or a thermosetting resin cured product, and preferably contains a thermal polymerization initiator in the thermosetting resin composition.

[Thermal polymerization initiator]
As thermal polymerization initiators, suitable compounds are all thermal polymerization initiators that can be used in radical polymerization reactions or ring-opening polymerization reactions.
Examples of the thermal polymerization initiator used in the radical polymerization reaction include organic peroxides, inorganic peroxides, organic silicon peroxides, hydroperoxides, azo compounds, thiol compounds, phenol resins, amino resins, halogen compounds, and aldehydes. A compound etc. can be mentioned.
Examples of the thermal polymerization initiator used in the ring-opening polymerization reaction include a latent thermal polymerization initiator in which a thermal polymerization initiator is placed in a microcapsule.

The thermal polymerization initiator is preferably liquid at 20 ° C. from the viewpoint of easy mixing with the resin (b) or the organic compound (c).
The content of the thermal polymerization initiator is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 5% by mass or less, with respect to the total amount of the thermosetting resin composition. Yes, and more preferably 1% by mass or more and 5% by mass or less.
If the content of the thermal polymerization initiator is within the above range, the thermosetting resin composition can be sufficiently cured, and the tackiness of the surface of the thermosetting product can be reduced.

In the present embodiment, selection of a thermal polymerization initiator is important in order to perform thermal polymerization suitably. The thermal stability of the thermal polymerization initiator is usually free by the 10 hour half-life temperature (10 h-t1 / 2), ie 50% of the initial amount of thermal polymerization initiator decomposes after 10 hours. Indicated at the temperature at which the radical is formed.
Details regarding the 10-hour half-life temperature are given in “Encyclopedia of Polymer Science and Engineering”, Volume 11, p. 1 and later, John Wiley & Sons, New York, 1988.
The 10-hour half-life temperature of the thermal polymerization initiator is preferably at least 60 ° C, more preferably at least 70 ° C, and even more preferably 80 ° C to 150 ° C.

As the thermal polymerization initiator, an organic peroxide is particularly preferable from the viewpoint of thermosetting and compatibility with the thermosetting resin composition.
Examples of the thermal polymerization initiator include t-butyl peroctanoate, t-amyl peroctanoate, t-butyl peroxyisobutyrate, t-butyl peroxymaleate, t-amyl perbenzoate, di-peroxyphthalate di- Peroxyesters such as t-butyl, t-butyl perbenzoate, t-butyl peracetate, and 2,5-di (benzoylperoxy) -2,5-dimethylhexane; 1,1-di (t-amylperoxy) ) Diperoxyketals such as cyclohexane, 1,1-di (t-butylperoxy) cyclohexane, 2,2-di (t-butylperoxy) butane, and ethyl 3,3-di (t-butylperoxy) butyrate; Di-t-butyl peroxide, t-butyl cumyl peroxide, dicumyl peroxide, and 2,5-di (t-butyl peroxide) Dialkyl peroxides such as dibenzoyl peroxide and diacetyl peroxide; t such as t-butyl hydroperoxide, t-amyl hydroperoxide, pinane hydroperoxide, and cumyl hydroperoxide -Alkyl hydroperoxides can be mentioned.

As a thermopolymerizable initiator, an azo compound may be mentioned as a preferable compound when forming a cushion layer containing bubbles.
Examples of the azo compound include 1- (t-butylazo) formamide, 2- (t-butylazo) isobutyronitrile, 1- (t-butylazo) cyclohexanecarbonitrile, 2- (t-butylazo) -2-methylbutane. Nitriles, 2,2′-azobis (2-acetoxypropane), 1,1′-azobis (cyclohexanecarbonitrile), 2,2′-azobis (isobutyronitrile), and 2,2′-azobis (2- Methylbutanenitrile) and the like.

[Fine particles]
Inorganic fine particles, organic fine particles, and / or organic-inorganic composite fine particles can be added to the sheet-like resin. By adding these fine particles, it is possible to improve the mechanical properties of the sheet-like resin obtained by curing, improve the wettability of the surface of the sheet-like resin, and adjust the viscoelastic properties of the sheet-like resin.
The material of the inorganic fine particles or organic fine particles is not particularly limited, and known fine particles can be used.
Examples of the organic / inorganic composite fine particles include fine particles in which an organic layer or organic fine particles are formed on the surface of inorganic fine particles, or fine particles in which an inorganic layer or inorganic fine particles are formed on the surface of organic fine particles.

As the fine particles, for the purpose of improving the mechanical properties of the sheet-like resin, high-rigidity inorganic fine particles such as silicon nitride, boron nitride, and silicon carbide, or organic fine particles such as polyimide can be used.
In order to improve the solvent resistance of the obtained sheet-like resin, inorganic fine particles or organic fine particles formed of a material having a good swelling property in the solvent to be used can be added.

  When forming a concavo-convex pattern on the surface of a cylindrical printing original plate by a laser engraving method, inorganic porous fine particles having excellent adsorption and removal characteristics of a viscous liquid residue generated in the laser engraving process may be added.

  The fine particles are not particularly limited, and examples thereof include porous silica, mesoporous silica, silica-zirconia porous gel, porous alumina, and porous glass.

  It is preferable that the number average particle diameter of the fine particles is 0.01 to 100 μm. The number average particle diameter of the fine particles is preferably 0.1 to 20 μm, more preferably 1 to 10 μm. When fine particles having a number average particle size within the above range are used, there are inconveniences such as increase in viscosity, entrainment of bubbles, and generation of a large amount of dust when mixing with the resin (b) and the organic compound (c). As a result, unevenness does not occur on the surface of the sheet-shaped resin.

  In the present embodiment, the average particle size of the fine particles means a value measured using a laser scattering type particle size distribution measuring apparatus.

  The particle shape of the fine particles is not particularly limited, and as the fine particles, spherical, flat, needle-shaped, amorphous, or particles having protrusions on the surface can be used, and from the viewpoint of wear resistance, Spherical particles are preferred.

The surface of the fine particles can be coated with a silane coupling agent, a titanium coupling agent, and other organic compounds and subjected to a surface modification treatment to use finer particles that are made more hydrophilic or hydrophobic.
In the present embodiment, one kind or two or more kinds of these fine particles can be selected.

[Composition ratio of resin composition]
The ratio of the resin (b), the organic compound (c), and the fine particles in the resin composition is preferably 5 to 200 parts by mass of the organic compound (c) with respect to 100 parts by mass of the resin (b). More preferably, it is 100 parts by mass.
The fine particles are preferably 1 to 100 parts by mass, more preferably 2 to 50 parts by mass, and further preferably 2 to 20 parts by mass with respect to 100 parts by mass of the resin (b).
When the ratio of the organic compound (c) is within the above range, it is easy to balance the hardness and tensile strength / elongation of the resulting resin cured product, and the shrinkage at the time of curing is within a small range to ensure thickness accuracy. Can do.

  A polymerization inhibitor, an ultraviolet absorber, a lubricant, a surfactant, a plasticizer, a fragrance, and the like can be added to the resin composition according to the use and purpose.

[Method for producing sheet-like resin]
As a method for producing the sheet-like resin, an existing resin molding method can be used.
Sheet resin production methods include, for example, a casting method, a method of extruding a resin from a nozzle or a die with a machine such as a pump or an extruder, a method of adjusting the thickness with a blade, a method of adjusting a thickness by calendaring with a roll, a spray, and the like The method of spraying using can be mentioned.
When the sheet-like resin is molded, it is possible to perform the molding while heating in a range that does not cause thermal decomposition, and rolling treatment, grinding treatment, and the like may be performed as necessary.

[Photocuring method]
The molded photosensitive resin composition is crosslinked by light irradiation to form a cured photosensitive resin.
While forming the photosensitive resin composition, it can be crosslinked by irradiation with light to form a cured photosensitive resin.
Examples of the light source used for photocuring include a high pressure mercury lamp, an ultrahigh pressure mercury lamp, an ultraviolet fluorescent lamp, a germicidal lamp, a carbon arc lamp, a xenon lamp, and a metal halide lamp.
The light irradiated to the photosensitive resin composition preferably has light having a wavelength of 200 nm to 400 nm.
Since many hydrogen abstraction type photopolymerization initiators have strong light absorption in this wavelength region, when having light with a wavelength of 200 nm to 400 nm, sufficiently ensure the curability of the surface of the photosensitive resin cured product. Can do. The light source used for photocuring may be one type, but since the curability of the resin may be improved by curing using two or more types of light sources having different wavelengths, two or more types of light sources may be used. preferable.

[Thermosetting method]
When the curable resin composition is a thermosetting resin composition, a thermosetting resin cured product is obtained by heat treatment.
Examples of the heating method include a method of irradiating infrared rays, a method of exposing to an atmosphere heated by an oven, a method of contacting an object such as a heated metal, and the like. The heating temperature is selected according to the type of thermal polymerization initiator.

[Cushion layer]
A cushion layer can also be formed on the sheet-like resin. A cushion layer can be provided on the lower part of the sheet-like resin (the side in contact with the cylindrical support (a)).
The cushion layer is preferably an elastomer layer having a Shore A hardness of 10 or more and 70 degrees or less, or an ASKER-C hardness of 20 degrees or more and 85 degrees or less measured with an ASKER-C type hardness tester.
When the Shore A hardness is 10 degrees or more, or the ASKER-C hardness is 20 degrees or more, the print quality can be ensured because it is appropriately deformed.
When the Shore A hardness is 70 degrees or less or the ASKER-C hardness is 85 degrees or less, it can serve as a cushion layer.
It is preferable that the Shore A hardness is 20 to 60 degrees or the ASKER-C hardness is 45 to 75 degrees. The Shore A hardness and the ASKER-C hardness are preferably selected depending on the material used for the cushion layer. The difference between the two types of hardness stems from the difference in the shape of the pushers of the hardness meter used for measurement. In the case of a uniform resin composition, it is preferable to use Shore A hardness, and in the case of a non-uniform resin composition such as a foamable base material such as foamed polyurethane and foamed polyethylene, it is preferable to use ASKER-C hardness. ASKER-C hardness is a measuring method based on JIS K7312 standard.

The material for the cushion layer is not particularly limited, and examples thereof include elastomers having rubber elasticity such as thermoplastic elastomers, photocurable elastomers, and thermosetting elastomers.
From the viewpoint of processability to a cylindrical printing plate, it is convenient and preferable to use a liquid photosensitive resin composition that is cured by light and to use a material that becomes an elastomer after curing.

  The cushion layer preferably contains a cured resin and contains bubbles or organic fine particles. It is preferable to use organic microparticles that are hollow microcapsules, in which inorganic microparticles are attached to the surface of the hollow microcapsules. The average particle diameter of the organic fine particles is preferably 1 μm or more and 500 μm or less, more preferably 10 μm or more and 300 μm or less, and further preferably 80 μm or more and 200 μm or less.

The density of the cushion layer is preferably 0.1 g / cm ³ or more and 0.9 g / cm ³ or less, more preferably 0.3 g / cm ³ or more and 0.7 g / cm ³ or less, and still more preferably 0. .4g / cm ³ or more 0.6g / cm ³ or less.
If the density of the cushion layer is within the above range, the impact applied to the laser engraving layer in the printing process can be sufficiently absorbed.

  Examples of the thermoplastic elastomer used for the cushion layer include styrene thermoplastic elastomers such as SBS (polystyrene-polybutadiene-polystyrene), SIS (polystyrene-polyisoprene-polystyrene), and SEBS (polystyrene-polyethylene / polybutylene-polystyrene), Examples include olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, ester-based thermoplastic elastomers, amide-based thermoplastic elastomers, silicon-based thermoplastic elastomers, and fluorine-based thermoplastic elastomers.

The photocurable elastomer used for the cushion layer is a composition in which a thermoplastic elastomer is mixed with a photopolymerizable monomer, a plasticizer, a photopolymerization initiator, etc., and a liquid resin is mixed with a photopolymerizable monomer, a photopolymerization initiator, etc. And the like.
Unlike the design concept of the photosensitive resin composition, in which the function of forming a fine pattern is an important element, it is not necessary to form a fine pattern using light, and the necessary mechanical properties can be obtained by curing it by full exposure. Since it is sufficient to ensure the strength, the degree of freedom in selecting the material is extremely high.

  The elastomer used for the cushion layer may be a sulfur cross-linked rubber, organic peroxide, phenol resin initial condensate, quinone dioxime, metal oxide, and non-sulfur cross-linked rubber using a compound such as thiourea as a cross-linking agent. . It is also possible to use an elastomer obtained by three-dimensional crosslinking using a curing agent that reacts with telechelic liquid rubber.

  The cushion layer may be a cushion layer made of foamed polyurethane, foamed polyethylene or the like and having independent or open cells in the layer, and commercially available cushion materials and cushion tapes can also be used. An adhesive or a pressure-sensitive adhesive may be applied to one side or both sides of the layer.

[Laser engraving]
In the present embodiment, when the cured resin is used as a printing substrate on which a pattern is formed by using a laser engraving method, the laser engraving method uses a computer as a digital data to form an image to be formed. To create a relief image on the printing substrate. Any laser beam may be used for the laser engraving as long as the original plate includes a wavelength having absorption. However, in order to perform engraving at a high speed, a laser beam having a high output is preferable. And infrared or infrared emitting solid lasers such as YAG lasers and semiconductor lasers.
The second harmonic of a YAG laser having an oscillation wavelength in the visible light region, a copper vapor laser, an ultraviolet laser having an oscillation wavelength in the ultraviolet region, such as an excimer laser, and a YAG laser wavelength-converted to the third or fourth harmonic are organic Ablation processing that cuts the bond of molecules is possible, and it is suitable for fine processing. The laser may be continuous irradiation or pulse irradiation.

  Laser engraving is carried out in an oxygen-containing gas, generally in the presence of air or an air stream, but can also be carried out in the presence of carbon dioxide or nitrogen gas. After engraving is finished, the powdery or liquid substance slightly generated on the relief printing plate surface is washed with an appropriate method such as water containing a solvent or a surfactant, or a water-based cleaning agent is irradiated by a high-pressure spray or the like. Alternatively, it may be removed using a method of irradiating high-pressure steam.

  In this embodiment, after engraving to form a concave pattern by irradiating laser light, following the step of removing powdery or viscous liquid residue remaining on the plate surface, the surface of the printing plate on which the pattern is formed has a wavelength of 200 nm to Post-exposure by irradiating with 450 nm light can also be performed. This is an effective method for removing tack on the surface. The post-exposure may be performed in any environment such as air, inert gas atmosphere, and water. This is particularly effective when the photosensitive resin composition used contains a hydrogen abstraction type photopolymerization initiator. Furthermore, before the post-exposure step, the printing plate surface may be treated and exposed to a treatment liquid containing a hydrogen abstraction type photopolymerization initiator. Moreover, you may expose in the state which immersed the printing plate in the process liquid containing a hydrogen drawing-type photoinitiator.

  The cylindrical printing original plate manufactured by the cylindrical printing original plate forming apparatus according to the present embodiment includes, as its use, a printing original plate or a printing plate used in printing techniques such as flexographic printing, dry offset printing, and gravure printing. it can. Narrow webs such as flexographic label printing, which require a highly accurate printed matter, and curved offset printing such as can offset printing and tube printing are preferred applications.

In printing, when the ink contains an aliphatic hydrocarbon and / or an aromatic hydrocarbon, the sheet-like resin preferably contains a polycarbonate, polyurethane, polyamide, polyvinyl alcohol, or vinyl alcohol-vinyl acetate copolymer. These resin materials are preferable because they have resistance to the above-mentioned solvents.
Examples of aliphatic hydrocarbons include compounds such as hexane, heptane, octane, nonane, decane, cyclohexane, methylcyclohexane, cyclooctane, cyclodecane, dipentene, rubber volatile oil, mineral spirits, and high boiling petroleum solvents (ink oil). Can do.
Aromatic hydrocarbons include compounds such as toluene, xylene, dimethylbenzene, dichlorobenzene, solvent naphtha, and tetralin.

  Hereinafter, the present embodiment will be described more specifically with reference to examples and comparative examples. However, the present embodiment is not limited only to these examples. The measurement method and the evaluation method used in this embodiment are as follows.

[Measuring method]
(1) Laser engraving Laser engraving is a carbon dioxide laser engraving machine (ZED-mini-1000, UK, manufactured by ZED, USA, coherent, equipped with a 250 W carbon dioxide laser with an oscillation wavelength of 10.6 μm) It was performed using. Engraving was performed by creating a dot pattern (120 lines / inch, area ratio 10%). The engraving depth was 0.55 mm.

(2) Viscosity The viscosity of the resin composition was measured at 20 ° C. using a B-type viscometer (trademark, B8H type; manufactured by Tokyo Keiki Co., Ltd., Japan).

(3) Measurement of number average molecular weight The number average molecular weights of the resin (b) and the organic compound (c) were determined by conversion with polystyrene having a known molecular weight using a gel permeation chromatography method (GPC method). Using a high-speed GPC apparatus (Japan, manufactured by Tosoh Corporation, HLC-8020) and a polystyrene-filled column (TSKgel GMHXL; manufactured by Tosoh Corporation, Japan), the measurement was performed using tetrahydrofuran. The column temperature was set to 40 ° C. As a sample to be injected into the GPC apparatus, a tetrahydrofuran solution having a resin concentration of 1% by mass was prepared, and the injection amount was 10 μL. A differential refractometer was used as the detector.

Example 1
[Cylindrical printing plate making machine 1]
As a mechanism that can hold and rotate the air cylinder, a small lathe with a three-claw chuck and a core pushing tailstock was modified, and a stepping motor with an encoder was attached as a rotating mechanism to enable low-speed rotation. The fiber reinforced plastic sleeve and the metal sleeve can be mounted by ejecting air from the pores of the air cylinder and can be fixed by stopping the ejection of air.
As shown in FIG. 1, two rolls (16, 17) supporting the glass hollow cylinder 15 are installed on the upper part of the air cylinder 10, and the roll 16 can rotate in synchronization with the rotation of the air cylinder 10. Attached. The other roll 17 is a mechanism that supports it so that it can freely rotate in the circumferential direction. A glass hollow cylinder 15 was held on the two rolls (16, 17). The two rolls (16, 17) were provided with a vertical movement mechanism that is driven by a stepping motor so that the rolls can move up and down. The sheet-like resin 12 is placed on the cylindrical support (a) 11, and the positions of the two rolls (16, 17) are determined so that the glass hollow cylinder 15 is in contact with the sheet-like resin 12 and does not move. . The glass hollow cylinder 15 has an inner diameter of 300 mm and a thickness of 5 mm. The light transmittance at 1064 nm which is the wavelength of the laser beam of the glass hollow cylinder 15 used was 95% or more.
As a laser light source, a continuous wave fiber laser (“REDENERGY”, manufactured by SPI, UK) (oscillation wavelength: 1064 nm, beam diameter: 3 mm, oscillation frequency: 125 kHz, time half-width: 20 nanoseconds) is used as a laser light source. Then, a laser head 14 in which a condenser lens was attached to the output head of the fiber laser was produced. The laser head 14 is installed inside the glass hollow cylinder 15, and the laser head 14 and the linear motor 23 are connected so that the laser head 14 moves smoothly in the long axis direction by the linear motor 23 in the glass hollow cylinder 15. A uniaxial drive system having a jig 24 was introduced. Further, the laser head 14 was attached to a drive mechanism that can be adjusted so that the interface between the cylindrical support (a) 11 and the sheet-like resin 12 is in focus by moving the laser head 14 up and down. A stepping motor is also used for driving the laser head 14 in the vertical direction. The diameter of the laser beam (13) at the focal point was 2 mm.
While moving the laser head 14 in the long axis direction of the glass hollow cylinder 15, the interface between the cylindrical support (a) 11 and the sheet-like resin 12 was welded linearly by irradiating laser light. During the welding with the laser, the cylindrical support (a) 11 was fixed so as not to move. Next, the cylindrical support (a) 11 was rotated by a predetermined amount and welded in the same manner, and the entire surface of the sheet-like resin was welded to the cylindrical support (a) 11. It adjusted with rotation of the roll 16 so that the glass-made hollow cylinder 15 might rotate by the same amount synchronizing with rotation of the cylindrical support body (a) 11. Laser welding was performed in such a manner that the cylindrical support (a) 11 and the sheet-like resin 12 were always in contact with each other at the portion to be welded by laser.

[Preparation of sheet resin]
As the resin (b), a polycarbonate polyurethane having a number average molecular weight of about 100,000 (manufactured by Dainichi Seika Co., Ltd., “Resamine (registered trademark) P890”) 70 parts by mass, as the organic compound (c), phenoxyethyl methacrylate (molecular weight 190) 30 parts by mass and trimethylolpropane triacrylate (molecular weight 338) 1 part by mass, as fine particles, porous fine powder silica (manufactured by Fuji Silysia Chemical Co., Ltd., “Cyrossphere (registered trademark) C-1504”) 5 parts by mass, light As polymerization initiators, 0.5 parts by mass of benzophenone and 0.6 parts by mass of 2,2-dimethoxy-2-phenylacetophenone and 0.5 parts by mass of 2,6-di-t-butylacetophenone as stabilizers were small. Mixing at a temperature of 130 ° C. using a capacity press kneader (“D1-5”, manufactured by Moriyama Co., Ltd.), photosensitive resin A composition was prepared. On the PET film (manufactured by Toray Industries, Inc.) having a thickness of 50 μm, a urethane adhesive is thinly applied to the surface using a biaxial extruder (“KZW-TW”, manufactured by Technobel Co., Ltd.). A sheet-like resin was formed by extruding at a thickness of 0.4 mm and sandwiched between 50 μm-thick PET cover sheets (manufactured by Fujimori Kogyo Co., Ltd.) subjected to silicone release treatment. Solid at ℃.
The obtained sheet-like resin was cut into a width of 180 mm and a length of 710 mm. Before wrapping around a hollow cylindrical support, it is irradiated with 4000 mJ / cm ² (integrated light quantity at 350 nm) with UV light emitted from a chemical lamp (“10R”, Lankoku, Philips) on a glass plate and photocured. A sheet-like resin was obtained.

[Manufacture of cylindrical printing original plate]
Shrink molded from PET in which carbon black (manufactured by Tokai Carbon Co., Ltd.) is kneaded on a glass fiber reinforced plastic sleeve (manufactured by Polybest, Germany) having an inner diameter of 225 mm, a thickness of 1 mm, and a width of 200 mm mounted on an air cylinder. The tube was covered and heated to shrink the tube and adhere to a glass fiber reinforced plastic sleeve. Thereafter, a sheet-like resin was wound, and both were welded using a cylindrical printing original plate manufacturing apparatus to produce a cylindrical printing original plate.
The outer diameter of the obtained cylindrical printing original plate was measured using a laser length measuring instrument (manufactured by Keyence Corporation, “LS-5120”) at 5 locations on the same circumference and 5 locations in the long axis direction. However, the part where the joint part of the sheet-like resin does not enter was selected for measurement. The outer diameter accuracy was ± 15 μm.

(Example 2)
[Cylindrical printing plate making machine 1]
As shown in FIG. 2, an acrylic plate 18 having a thickness of 5 mm is installed on the cylindrical support (a) 11, and a sheet-like resin is sandwiched between the cylindrical support (a) 11 and the acrylic plate 18. The device. The rolls 19 and 20 support the acrylic plate 18 and have a rotation mechanism so that the acrylic plate 18 can be moved to the left and right in accordance with the rotation of the cylindrical support (a) 11. Moreover, the roll 21 and the roll 22 are rolls for holding the acrylic plate 18 so as not to move upward, and are configured to freely rotate. The light transmittance of the acrylic plate 18 at a wavelength of 1064 nm was 95% or more.
The same laser head 14 as in Example 1 was used. The mechanism used in Example 1 was also used for the mechanism for moving the laser head 14 in the long axis direction of the cylindrical support (a) 11.

[Preparation of sheet resin]
As the resin (b), a polycarbonate polyurethane having a number average molecular weight of about 100,000 (manufactured by Dainichi Seika Co., Ltd., “Resamine (registered trademark) P890”) 70 parts by mass, as the organic compound (c), phenoxyethyl methacrylate (molecular weight 190) 30 parts by mass and trimethylolpropane triacrylate (molecular weight 338) 1 part by mass, as fine particles, porous fine powder silica (manufactured by Fuji Silysia Chemical Co., Ltd., “Cyrossphere (registered trademark) C-1504”) 5 parts by mass, stable As an agent, 0.5 part by mass of 2,6-di-t-butylacetophenone was mixed at a temperature of 130 ° C. using a small-capacity pressure type kneader (“Dri-5” manufactured by Moriyama Co., Ltd.), and then 70 ° C. Until it is cooled to t-butyl peroxy-2-ethylhexyl carbonate (Nippon Yushi Co., Ltd. Butyl E (registered trademark) ”) 1 part by mass was added to prepare a thermosetting resin composition. Between the obtained thermosetting resin composition, a PET film (manufactured by Toray Industries, Inc.) having a thickness of 50 μm, on which a urethane adhesive layer is applied, and a PET film (manufactured by Fujimori Kogyo Co., Ltd.) subjected to silicone release treatment. Inserted and hot pressed with two metal plates. A metal spacer having a thickness of 0.5 mm was inserted between the two metal plates, and heat treatment was performed at 130 ° C. for 30 minutes to obtain a thermally cured sheet-like resin.

[Manufacture of cylindrical printing original plate]
An aramid fiber reinforced plastic (epoxy resin) sleeve having a thickness of 0.4 mm was used as the cylindrical support (a), and was mounted on a metal air cylinder. The same shrink tube as in Example 1 was attached to the sleeve and brought into close contact therewith. The produced sheet-like resin was sandwiched between the cylindrical support (a) and the acrylic plate and adhered to the cylindrical support (a) by laser welding to produce a cylindrical printing original plate. The outer diameter accuracy of the obtained cylindrical printing original plate was within ± 15 μm.

[Manufacture and printing of cylindrical printing plates]
An uneven pattern was formed on the surface of the obtained cylindrical printing original plate at a linear velocity of 10 m / sec using a carbon dioxide laser engraving machine to obtain a cylindrical printing plate. Then, it mounted on the flexographic printing machine and printed on the polyethylene film using the solvent ink at a printing speed of 200 m / min. In the laser engraving process and the printing process, the sheet-like resin was not peeled off from the cylindrical support (a). Moreover, the printing quality of the halftone dot part of the obtained printed matter was also good.

INDUSTRIAL APPLICABILITY The present invention can provide a cylindrical printing original plate molding apparatus for manufacturing a cylindrical printing original plate with high productivity and high thickness accuracy by adhering a sheet-like resin on a cylindrical support.
The present invention has industrial applicability in printing fields such as flexographic printing, dry offset printing, and gravure printing.

The schematic side view of the cylindrical printing original plate manufacturing apparatus in Example 1 is shown. The schematic side view of the cylindrical printing original plate manufacturing apparatus in Example 2 is shown.

Explanation of symbols

1: Cylindrical printing original forming apparatus 10: Air cylinder 11: Cylindrical support (a)
12: Sheet resin 13: Laser beam 14: Laser head 15: Cylindrical material (for example, glass hollow cylinder)
16: Roll 17: Roll 18: Plate (for example, acrylic plate)
19: Roll 20: Roll 21: Roll 22: Roll 23: Linear motor 24: Connecting jig for laser head and linear motor

Claims (13)

A cylindrical printing original plate molding apparatus for adhering a sheet-like resin on a cylindrical support (a),
(1) a mechanism for holding the cylindrical support (a) and rotating it in the circumferential direction;
(2) a mechanism for holding a laser light-transmitting plate or cylinder and changing the distance from the surface of the cylindrical support (a);
(3) a laser light source disposed in the mechanism (2);
(4) The sheet resin is sandwiched between the plate or cylinder and the cylindrical support (a), and the sheet resin and laser light are absorbed through the plate or cylinder. An optical system for irradiating a laser beam on the interface with the cylindrical support (a);
(5) A cylindrical printing original plate forming apparatus comprising: a mechanism for moving a position irradiated with laser light in a long axis direction of the cylindrical support (a).   The cylindrical printing original plate forming apparatus according to claim 1, wherein the laser light source is a light source that emits laser light having a wavelength of 700 nm to 3 μm. The cylindrical support (a) is a hollow cylindrical support made of fiber reinforced plastic or metal,
The cylindrical printing original plate forming apparatus according to claim 1 or 2, wherein the mechanism (1) has a cylindrical object made of at least one material selected from the group consisting of metal, rubber, and plastic.   The said optical system (4) has a condensing lens and the mechanism in which the distance of this condensing lens and the surface of the said cylindrical support body (a) is changed, The any one of Claim 1 to 3 The cylindrical printing original plate forming apparatus described in 1.   The said mechanism (5) has a mechanism which changes the position of the said optical system (4) to a major axis direction, or a mechanism which scans a laser beam to a major axis direction, The any one of Claim 1 to 4 Cylindrical printing master forming equipment.   The laser beam is pulsed, the frequency of the pulse is 1 kHz or more and 500 MHz or less, the pulse time half width is 1 nanosecond or more and 50 milliseconds or less, and the average output is 0.1 W or more and 200 W or less, The cylindrical printing original plate forming apparatus according to any one of claims 1 to 5.   The material of the plate or cylinder is at least one material selected from the group consisting of glass and plastic, and the light transmittance at the wavelength of the laser beam to be used is 50% or more and 100% or less. The cylindrical printing original plate forming apparatus according to any one of claims 1 to 6. The cylindrical support (a) and the plate-like object or cylindrical object move synchronously,
The cylindrical support body (a) and the sheet-like resin have a portion that is always in contact, and the contacted portion is irradiated with laser light. The cylindrical printing original plate forming apparatus according to Item.   The cylindrical sheet according to any one of claims 1 to 8, wherein the sheet-like resin is made of at least one material selected from the group consisting of a thermoplastic resin, a photosensitive resin composition, and a thermosetting resin composition. Printing original plate forming equipment.   The cylindrical sheet according to claim 9, wherein the sheet-like resin is a sheet-like laminate in which a photosensitive resin cured product or a thermosetting resin cured product is laminated on a sheet-like support made of the thermoplastic resin. Printing original plate forming equipment.   The photosensitive resin composition or the thermosetting resin composition is polyamide, polyimide, polyurethane, polyester, polycarbonate, polyether polyol, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, and styrene. The cylindrical printing original plate forming apparatus according to claim 9, comprising at least one resin selected from the group consisting of -isoprene copolymers.   The cylindrical printing original plate according to any one of claims 1 to 11, which is an apparatus for producing a cylindrical printing original plate or a cylindrical printing plate used in flexographic printing, dry offset printing, or gravure printing applications. Molding equipment.   The cylindrical printing original plate forming apparatus according to claim 12, wherein the cylindrical printing original plate is a cylindrical printing original plate for laser engraving that forms a pattern on a surface by a laser engraving method.

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