JP2006315245A - Master for thermal stencil printing and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a master for thermal stencil printing which has excellent conveyability, while not impairing properties of perforation by a thermal head, nor losing features such as an excellent image quality and little set-off, and being free from jamming due to static electricity in a printing machine and from creasing on a drum, and a manufacturing method thereof. <P>SOLUTION: The master for thermal stencil printing is constituted by having a thermoplastic resin film 1 and also a porous resin film 2 and a reinforcing resin 3 provided in contact with the opposite end portions of the porous resin film 2, which are disposed at least on one side of the thermoplastic resin film 1. The reinforcing resin 3 is preferably in modes that it is provided at the opposite end portions of the master being parallel substantially to the direction of conveyance, that the thickness of the porous resin film 2 and that of the reinforcement resin 3 are equal, etc. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat-sensitive stencil printing master having excellent image quality and characteristics with little set-off and having excellent transportability, and a method for producing the heat-sensitive stencil printing master.

  Conventionally, porous thin paper mixed with hemp fiber, synthetic fiber, wood fiber, etc. as an ink permeable support is bonded to a thermoplastic resin film with an adhesive, and a low molecular surfactant is applied to the film surface. Thermal stencil printing masters provided as antistatic agents are known and widely used.

However, conventional heat-sensitive stencil masters have the following problems.
(1) A large amount of adhesive accumulates in the part where the film overlaps the film and the part where the film comes into contact (in the form of a bird's web), making it difficult for the thermal head to perforate the part, preventing the passage of ink, and printing Unevenness occurs.
(2) The fibers themselves obstruct the passage of ink and cause printing unevenness.
(3) Porous thin paper or the like is expensive, and loss due to laminating is large, and the master becomes expensive.
(4) When the printed papers overlap, so-called set-off occurs where the ink adheres to the back side of the overlapped paper.

  In order to solve the above problems, various proposals have been made for a heat-sensitive stencil printing master in which an ink-permeable support made of fibers is bonded to a thermoplastic resin film. For example, Patent Document 1 proposes a support using ultrafine fibers having a fineness of 1 denier or less. According to this proposal, the problems (2) and (4) can be solved, but the problems (1) and (3) still remain.

  Patent Document 2 proposes a method of forming a radiation curable heat-resistant resin pattern having a substantially closed shape on a film by a printing method such as gravure, offset, flexo or the like. However, in the above method, it is difficult to make the thickness of the resin layer as the ink permeable support 50 μm or less, and even if the thickness of the resin layer can be formed to about 30 μm, the thickness is not sufficient. There is a problem that the resin layer hinders perforation by the thermal head, the resin layer cannot be perforated cleanly, and printing unevenness such as blurring and blurring occurs.

  Patent Document 3 proposes a master for thermal stencil printing having a porous layer obtained by applying a liquid mixture of fine particles such as a water-dispersible polymer and colloidal silica to the film surface and drying it. However, the porous layer obtained by this method is poor in printing ink, and the conventional heat-sensitive stencil printing ink has a problem that a sufficient concentration cannot be obtained during printing.

Patent Document 4 proposes a heat-sensitive stencil printing master that is substantially composed of only a film without using a support. According to this proposal, the problems (1), (2), and (3) can be solved. However, (i) When the film has a thickness of 10 μm or less, the stiffness of the film is weak and the conveyance becomes difficult. In addition, (ii) when the film has a thickness of 5 μm or more, there is a problem that the thermal sensitivity of the film is reduced and it is difficult to perforate with a thermal head.
In order to solve these problems, for example, in Patent Document 5, the film is wound around the plate cylinder peripheral wall portion of a stencil printing machine without being cut, and the entire film is also printed with the rotation of the plate cylinder during printing. A method of rotating is proposed. However, in this method, since the film and the loading / unloading plate unit rotate with the rotation of the plate cylinder during printing, the rotation moment increases. Further, there is a large variation from the rotation center of the gravity center, and in order to solve these problems, there is a problem that the printing press is heavy and large.

In order to solve the above problem, for example, Patent Document 6 discloses a resin, a good solvent for the resin (referred to as a solvent capable of dissolving the resin), and a poor solvent (substantially does not dissolve the resin and the evaporation rate is A master for thermal stencil printing in which a fluid containing a solvent slower than the evaporation rate of a good solvent is applied to a thermoplastic resin film and dried to form a porous resin film has been proposed. In this proposed fluid, the porous resin film consisting of a three-dimensional network structure is formed by drying the resin due to the relative increase in poor solvent due to evaporation of the good solvent and concentration of the liquid during the drying process. Formed on top.
Patent Document 7 discloses a thermosensitive stencil printing master in which a fluid mainly composed of a water-in-oil (W / O) emulsion is coated on a thermoplastic resin film and dried to form a porous resin film. Proposed. In the proposed fluid, a portion of water droplets is dried to form pores in the drying process, and a porous resin film is formed on the thermoplastic resin film.
The heat-sensitive stencil printing masters of Patent Documents 6 and 7 are superior to the masters known so far, and hardly cause problems in normal use. However, these heat-sensitive stencil printing masters have a lower bending stiffness than a master using a Japanese paper type porous support, which is disadvantageous for conveyance in a printing press and winding around a drum. Actually, when plate-making printing is performed in a low-temperature and low-humidity environment, the master sticks to the inner wall of the printing machine due to static electricity generated during transportation, and smooth transportation and winding around the printing drum cannot be performed. There is a problem in that the printing machine stops in a wrinkled state or a jam occurs during winding.

  In order to solve this problem, for example, a heat-sensitive stencil master having a porous resin film on a thermoplastic resin film and further having a porous fiber film on the porous resin film has been proposed. (See Patent Document 8). In this proposed heat-sensitive stencil master, the transportability in the printing press and the winding property to the drum are improved. However, the fiber itself prevents the ink from passing through and prevents printing unevenness. It is necessary to use a porous fiber membrane having a basis weight and using fine fibers. Such a porous fiber membrane is expensive and has a large loss due to laminating, which makes the master expensive. Furthermore, a low basis weight porous fiber membrane using fine fibers has a low bending stiffness, and there is also a problem that it is difficult to obtain sufficient stiffness only by laminating them.

  On the other hand, for the purpose of enhancing transportability, for example, a plate-making part made of a thermoplastic resin film for each plate length having a porous material on the film and used for one plate-making printing, There has been proposed a stencil printing master that is provided in the short direction of the plate making part and has a plate making part including a reinforcing part (see Patent Document 9). However, in this proposal, since it is necessary to provide reinforcing portions at many places, there is a problem that the reinforcing range is widened and the cost is increased. In addition, since the reinforcing portion is provided across the master, the printing range of the master is included, and there is a problem that the ink is deteriorated at the portion where the reinforcing portion is provided.

  Therefore, the master for thermal stencil printing without losing the excellent image quality and the characteristic of little set-off without damaging the punching performance of the thermal head, and without wrinkles on the drum or static on the master printing machine. Has not been provided yet, and its rapid development is desired.

Japanese Patent Laid-Open No. 3-193445 Japanese Patent Laid-Open No. 62-198459 Japanese Patent Laid-Open No. 4-7198 JP 54-33117 A Japanese Patent Publication No. 5-70595 Japanese Patent Laid-Open No. 10-24667 Japanese Patent Laid-Open No. 11-235858 JP-A-10-147075 JP-A-6-239047

  This invention is made | formed in view of this present condition, and makes it a subject to solve the said various problems in the past and to achieve the following objectives. In other words, the present invention does not lose the characteristics of excellent image quality and less set-off without impairing the punchability of the thermal head, and also causes the generation of wrinkles on the drum or the drum due to static electricity in the master printer. An object of the present invention is to provide a heat-sensitive stencil printing master having excellent transportability and a method for producing the heat-sensitive stencil printing master.

Means for solving the problems are as follows. That is,
<1> A thermoplastic resin film, a porous resin film on at least one surface of the thermoplastic resin film, and a reinforcing resin disposed in contact with both ends of the porous resin film This is a heat-sensitive stencil printing master. Since the heat-sensitive stencil printing master according to <1> is provided with a reinforcing resin in contact with both ends of the porous resin film, the reinforcing resin can impart excellent transportability to the master. it can. In addition, since the reinforcing resin is disposed only at both ends of the porous resin film, the reinforcing range is narrow and the cost is low as compared with the case where reinforcement is applied to the entire surface or many places. Furthermore, since the reinforcing range is out of the printing range at both ends of the master, there is no possibility that the ink may deteriorate due to the reinforcing.
<2> The heat-sensitive stencil printing master according to <1>, wherein the reinforcing resin is disposed at both ends substantially parallel to the conveyance direction of the master.
<3> The thermal stencil printing master according to any one of <1> to <2>, wherein the thickness of the porous resin film is equal to the thickness of the reinforcing resin.
<4> The heat-sensitive stencil printing master according to any one of <1> to <3>, comprising a porous fiber film on a porous resin film.
The thermosensitive stencil printing master described in <4> has a porous fiber film on the porous resin film, whereby the bending rigidity of the reinforcing resin is improved. In addition, since the ink is uniformly dispersed when passing through the porous resin film, unlike the master in which the porous fiber film is directly laminated on the film, the print image quality is not adversely affected. Moreover, since it is a porous fiber membrane, it is easy to obtain. Furthermore, there is an advantage that the strength and ink permeability can be controlled relatively easily by selecting the type of fiber as the raw material.

<5> The heat-sensitive stencil printing master according to any one of <1> to <4>, wherein the reinforcing resin is a water-in-oil (O / W) emulsion resin. In the heat-sensitive stencil printing master described in <5>, a water-in-oil (O / W) emulsion resin, which is a water-based coating liquid, is used as the reinforcing resin, so that it contacts the porous resin film. Even in this case, there is an advantage of not causing a problem such as dissolving the porous resin film to block the pores. In addition, since the load on the environment is small and no special equipment is required for coating, reinforcement can be easily performed. Furthermore, the water-in-oil (O / W) emulsion resin can be diluted with water and the viscosity of the coating solution can be easily adjusted, but the resin obtained after drying is excellent in water resistance.
<6> The thermal stencil printing master according to any one of <1> to <5>, wherein the reinforcing resin contains at least one of an electron beam curable resin and an ultraviolet curable resin. In the heat-sensitive stencil printing master described in <6>, the reinforcing resin includes at least one of an electron beam curable resin and an ultraviolet curable resin which are liquids during coating. Therefore, it can be easily applied, and is cross-linked and solidified by irradiation with an electron beam or ultraviolet rays.
<7> The heat-sensitive stencil printing master according to any one of <1> to <6>, wherein the reinforcing resin is provided by either drying or curing after applying a reinforcing resin coating solution containing the reinforcing resin. . For reinforcement, when a porous fiber membrane or other sheet-like material is laminated on both ends of the master, the thickness of the portion increases, and when the master is wound into a roll, irregularities are formed on the surface. As a result, the smoothness of the film surface is lowered, the contact property of the film with the thermal head is lowered during plate making, and the perforation sensitivity is lowered. However, in the heat-sensitive stencil printing master described in <7>, it is preferable that the reinforcing resin coating liquid flows into the voids of the porous fiber membrane and can be reinforced without changing the thickness of the master.
With a conventional master that has only a porous fiber membrane bonded to a film, the lateral continuity of the porous fiber membrane gap is high, and the reinforcement applied only to both ends of the master protrudes to the printed image part before drying or curing In many cases, practical application was difficult. The heat-sensitive stencil printing master described in <7> is low in lateral continuity of the voids of the porous resin film, and therefore, when a liquid is applied, it does not flow into the printed image area before drying or curing, Excellent productivity. In addition, charging during transport in the printing press is suppressed, and transport jams are less likely to occur.

<8> The heat-sensitive stencil printing master according to any one of <1> to <7>, wherein the coating amount of the nonvolatile resin in the reinforcing resin coating liquid containing the reinforcing resin is 2.0 to 40 g / m ² .
<9> The heat-sensitive stencil printing master according to <8>, wherein the nonvolatile content coating amount is 13 to 40 g / m ² .
<10> The thermal stencil printing master according to any one of <1> to <9>, wherein the reinforcing resin has a width of 5 to 15 mm.
<11> The thermal stencil printing master according to any one of <1> to <10>, wherein the reinforcing resin has a bending stiffness of 20 to 200 mN.

<12> For heat-sensitive stencil printing, including a porous resin film forming step of forming a porous resin film by applying a coating liquid for forming a porous resin film on a thermoplastic resin film and drying it. It is a manufacturing method of a master. In the method for producing a thermosensitive stencil printing master described in <12>, since the pore diameter uniformity of the porous resin film is high and the piercing property by the thermal head is high, the image quality is excellent, the settling is small, The master which has the characteristic that there is no generation | occurrence | production of the jam and the wrinkle on a drum by static electricity of can be manufactured efficiently.
Moreover, since the shape of the obtained porous resin film does not depend on the solubility of the resin, it is less affected by temperature and humidity, and is excellent in that the formed film shape is highly reproducible. Furthermore, since the degree of freedom of the formulation is high and the range in which the porous resin film can be formed is wide, it is excellent in that the range in which the viscosity of the coating solution can be adjusted by the ratio of the oil phase / water phase, the resin concentration, the resin molecular weight, and the like.

  According to the present invention, it is possible to solve the problems in the past, without damaging the piercing property of the thermal head, without the thermal head corrosion problem, without losing the characteristics of excellent image quality and less setback, It is possible to provide a heat-sensitive stencil printing master having excellent transportability without causing jamming or wrinkles on the drum due to static electricity in the master printing machine, and a method for producing the heat-sensitive stencil printing master.

(Master for thermal stencil printing)
The heat-sensitive stencil printing master of the present invention is disposed on a thermoplastic resin film, on at least one surface of the thermoplastic resin film, in contact with both ends of the porous resin film. And a reinforcing resin. Here, the reinforcing resin has a function of reinforcing the transportability of the heat-sensitive stencil printing master. That is, the reinforcing resin does not improve the bending rigidity of the master itself, but prevents the occurrence of wrinkles on the drum or the drum due to static electricity in the master's printing machine by the high bending rigidity of the reinforcing resin itself. is there.
The direction in which the reinforcing resin is disposed is not particularly limited as long as it is at both ends of the porous resin film. However, since excellent transportability can be reliably imparted, it is substantially parallel to the transport direction of the thermal stencil printing master. It is preferable to be arranged in Further, the reinforcing resin may be arranged in the longitudinal direction of the heat-sensitive stencil printing master or the transversal direction as long as it is parallel to the transport direction. Since it is conveyed in the direction, it is preferably arranged in the longitudinal direction.
The thickness of the porous resin film and the thickness of the reinforcing resin may be different, but in order to make the bending stiffness of the master an appropriate strength that has good transportability, the thickness should be the same. preferable.

Here, FIGS. 1 and 2 are schematic cross-sectional views showing an example of the heat-sensitive stencil printing master of the present invention. In the master shown in FIG. 1, the porous resin film 2 and the porous resin film 2 are formed on the thermoplastic resin film 1. Reinforcing resins 3 and 3 are provided in contact with both end portions substantially parallel to the longitudinal direction (conveying direction) of the porous resin film 2 and arranged with the same thickness as the porous resin film.
In the master shown in FIG. 2, the porous resin film 2 and the porous fiber film 4 are provided on the thermoplastic resin film 1 in this order, and the longitudinal direction of the porous resin film 2 and the porous fiber film 4 ( Reinforcing resins 3 and 3 are disposed in contact with both end portions substantially parallel to the transport direction) and have the same thickness as the porous resin film 2 and the porous fiber film 4. In the embodiment having the porous fiber membrane shown in FIG. 2, the total thickness of the porous resin membrane and the porous fiber membrane may be different from the thickness of the reinforcing resin. From the same viewpoint as in the case of only the porous resin film shown, it is preferable that the thickness is the same as shown.

-Thermoplastic resin film-
The thermoplastic resin film is not particularly limited in material, thickness, size, shape and the like, and can be appropriately selected from known ones commonly used for heat-sensitive stencil printing masters according to the purpose. As the material, a thermoplastic resin is suitable, and examples thereof include polyvinyl chloride resin, vinyl chloride-vinylidene chloride copolymer, polyethylene resin, polypropylene resin, and polyester resin.
As the thermoplastic resin film, a biaxially stretched resin film is particularly preferable, and examples thereof include a biaxially stretched polyester resin film, a biaxially stretched polyethylene resin film, and a biaxially stretched polypropylene resin film.
0.5-10 micrometers is preferable and, as for the thickness of the said thermoplastic resin film, 1.0-5.0 micrometers is more preferable. If the thickness is less than 0.5 μm, it may be too thin to apply a porous resin layer coating liquid described later, and if it exceeds 10 μm, it may be difficult to perforate the thermal head. is there.

-Porous resin membrane-
The structure of the porous resin film is connected in an irregular rod shape, spherical shape, or branch shape (short structural units such as Japanese paper are not intertwined, and a combination of simple shapes formed by printing etc. Suitable examples include those having a complicated three-dimensional structure, a structure resembling a so-called yarn string, a honeycomb-like structure, a honeycomb-like structure, and the like. The porous resin film and the porous fiber film, which will be described later, make up for the insufficient strength of the thermoplastic resin film alone, improve the transportability and printing durability of the master, and make the ink that passes through the master uniform during printing. There is an effect of dispersing and improving the image quality.

  As a first method for forming a porous resin film having the above-described structure, for example, as disclosed in JP-A-10-24667, a good resin solvent (resin can be dissolved) that forms a porous resin film And a poor solvent (which means a solvent that does not substantially dissolve the resin and has an evaporation rate slower than the evaporation rate of the good solvent), and the resin and the good solvent for the resin. And a fluid containing a poor solvent is applied in a semi-precipitated state on a thermoplastic resin film and dried. The fluid containing this resin, its good solvent, and poor solvent has a three-dimensional network structure in which the good solvent evaporates first, the poor solvent increases relatively, the resin precipitates due to resin concentration, etc. Form a structure. In this first forming method, a porous resin film having a string-like structure is generally formed, and productivity can be increased by selecting a solvent that evaporates quickly such as ether or acetone.

  The resin material used for forming the porous resin film is not particularly limited and can be appropriately selected from known materials according to the purpose. For example, polyvinyl acetate resin, polyvinyl butyral resin, vinyl chloride- Vinyl resins such as vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, styrene-acrylonitrile copolymer; polyamide resins such as polybutylene resin and nylon; polyphenylene oxide resin, (meth) acrylate resin, polycarbonate Resins; Cellulose derivatives such as acetylcellulose, acetylbutylcellulose, acetylpropylcellulose, and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, a thermoplastic resin is preferably used in order to form a porous resin film having excellent ink permeability, which is an object of the present invention.

  The porous resin film may further contain, for example, a filler, an antistatic agent, a stick preventing agent, a surfactant, an antiseptic, an antifoaming agent, etc., as long as the purpose and effect of the present invention are not impaired. Can be added.

The filler is added to adjust the formation, strength, pore size, stiffness, etc. of the porous resin film. Here, the filler is a concept including pigments, powders, and fibrous substances, and among these, needle-like, plate-like, or fibrous fillers are particularly preferable.
The filler is not particularly limited and can be appropriately selected from known ones according to the purpose. For example, minerals such as magnesium silicate, sepiolite, potassium titanate, wollastonite, zonolite, gypsum fiber, etc. Needle-like fillers; artificial mineral-type needle-like fillers such as non-oxide-type needle-like whiskers and double oxide-type whiskers; plate-like fillers such as mica, glass flakes, and talc; carbon fibers, polyester fibers, glass fibers, vinylon fibers, Examples thereof include natural or synthetic fibrous fillers such as nylon fibers and acrylic fibers.
There is no restriction | limiting in particular as said pigment, According to the objective, it can select suitably according to the objective, For example, the organic polymer particle which consists of polyvinyl acetate resin, polyvinyl chloride resin, polymethyl acrylate resin, etc .; Examples thereof include inorganic pigments such as carbon black, zinc oxide, titanium dioxide, calcium carbonate, and silica. These may be used individually by 1 type and may use 2 or more types together.
The amount of the filler added is preferably 5 to 200 parts by mass with respect to 100 parts by mass of the resin. When the added amount of the filler is less than 5 parts by mass, curling may easily occur, and when it exceeds 200 parts by mass, the strength of the porous resin film may be reduced.

  The second method for forming the porous resin film is used when the good solvent and the poor solvent of the resin forming the porous resin film do not mix with each other, and disclosed in, for example, JP-A-11-23585. In this method, a fluid mainly composed of a W / O type (water-in-oil) emulsion is applied onto a thermoplastic resin film and dried to form a porous resin film. The porous resin film formed from this W / O type emulsion generally has a honeycomb-like structure and a honeycomb-like three-dimensional network structure. The porous resin film formed by the second forming method is formed by applying a fluid mainly composed of a W / O emulsion on a thermoplastic resin film and drying it. After the portion is dried, it becomes pores through which the ink passes, and the resin in the solvent (which may contain additives such as fillers and emulsifiers) becomes the structure.

  The resin is not particularly limited and may be appropriately selected from known ones according to the purpose. Examples thereof include acrylic resins, ester resins, urethane resins, acetal resins, olefin resins, and vinylidene chloride. Resin, epoxy resin, amide resin, styrene resin, vinyl resin, cellulose derivative, modified products thereof, or copolymers thereof. Among these, vinyl butyral resins and urethane resins are particularly preferable.

  For the formation of the W / O emulsion, a surfactant having a relatively strong lipophilic HLB of 2.5 to 6 is effective, but when a surfactant having an HLB of 8 to 20 is used in the aqueous phase, too. A more stable and uniform W / O emulsion can be obtained. The use of a polymeric surfactant is also one method for obtaining a more stable and uniform emulsion. In addition, addition of a thickener such as polyvinyl alcohol or polyacrylic acid to the aqueous system is effective for stabilizing the emulsion.

  In order to adjust the formation, strength, pore size, stiffness and the like of the porous resin film, an additive such as a filler can be further added to the porous resin film as necessary. Among these, needle-like, plate-like, or fibrous fillers are particularly preferable. In addition, as a filler, it can select suitably from the thing similar to the said 1st formation method.

Dried coating weight of the porous resin film in the first and second forming method is preferably from 0.3 to 30 g / ^{m 2,} and more preferably 20 to 30 g / ^{m 2.} The accumulation amount is less than 0.3 g / m ^2, may setoff of printed matter is degraded without the amount of ink deposited is controlled, to inhibit the passage of the ink exceeds 30 g / m ² Image When it is 20-30 g / m ² , the stiffness of the master itself is strong and it is advantageous in that it is excellent in handleability.

-Reinforcing resin-
The reinforcing resin is preferably used because it has a high reinforcing effect, is familiar with the porous resin film, and is low in cost.
There is no restriction | limiting in particular as said reinforcement resin, Although it can select suitably according to the objective, Since manufacture is easy and a porous resin film is not dissolved, water-soluble resin is preferable.
Examples of the water-soluble resin include starch, mannan, sodium alginate, galactan, tragacanth gum, gum arabic, pullulan, dextran, xanthan gum, glue, gelatin, collagen, casein, and other natural polymers; carboxymethylcellulose, hydroxymethylcellulose, methylcellulose, Semi-synthetic polymers such as hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, hydroxymethyl starch, carboxymethyl starch, and dialdehyde starch; neutralized products such as acrylic acid resin and sodium polyacrylate; polyvinylimide, polyvinyl alcohol, polyvinyl Pyrrolidone, polyethyleneimine, polyacrylamide, poly N-acryloylpyrrolidine, poly N-isopropyl Poly N-alkyl substituted acrylamides such as pill acrylamide; polyethylene oxide, polyvinyl methyl ether, styrene-maleic anhydride copolymer, styrene-acrylic acid copolymer, and polymers in which these are partially hydrophobic with alkyl groups Is mentioned. The acrylamide polymer and the acrylic polymer may be a copolymer type polymer in which the substituent is partially hydrophobized with an alkyl group. A block copolymer of polyethylene and polypropylene or polybutylene can also be used. The said water-soluble polymer may be used individually by 1 type, and may use 2 or more types together.
Among the water-soluble resins, a water-in-oil (O / W) emulsion resin is more preferable from the viewpoint of increasing the water resistance of the obtained reinforcing resin.
Examples of the water-in-oil (O / W) emulsion resin include, for example, polyvinyl acetate, acrylic acid ester, methacrylic acid ester, vinyl chloride, ethylene-vinyl acetate copolymer, vinyl acetate-acrylic acid ester copolymer, Styrene-acrylic acid ester copolymer, vinylidene chloride-acrylic acid ester copolymer, vinyl chloride-vinyl acetate copolymer, urethane-acrylic acid ester copolymer, urethane, acrylic, carnauba resin and the like can be mentioned.

In addition, as the reinforcing resin, an electron beam curable resin and an ultraviolet curable resin can be more suitably used from the viewpoint of performing strong reinforcement.
Examples of the electron beam curable resin and the ultraviolet curable resin include polyoxyethylene monoacrylate, polyoxyethylene diacrylate, polyoxyethylene monomethacrylate, polyoxyethylene diacrylate, 2-hydroxyethyl methacrylate, polyethylene glycol monomethacrylate, and polyethylene. Glycol monoacrylate, hydroxypropyl methacrylate, polypropylene glycol monomethacrylate, polypropylene glycol monoacrylate, poly (ethylene glycol-propylene glycol) monomethacrylate, polyethylene glycol-polypropylene glycol monomethacrylate, polyethylene glycol-polypropylene glycol monoacrylate, poly (ethylene glycol- Tetra Methylene glycol) monomethacrylate, poly (ethylene glycol-tetramethylene glycol) monoacrylate, poly (propylene glycol-tetramethylene glycol) monomethacrylate, poly (propylene glycol-tetramethylene glycol) monoacrylate, propylene glycol polybutylene glycol monomethacrylate, Propylene glycol polybutylene glycol monoacrylate, methoxypolyethylene glycol monomethacrylate, methoxypolyethylene glycol monoacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, polyethylene glycol diacrylate, polypropylene glycol dimethacrylate , Polypropylene glycol diacrylate, polytetramethylene glycol dimethacrylate, polytetramethylene glycol diacrylate, and the like. These may be used individually by 1 type and may use 2 or more types together.

The coating amount of the reinforcing resin is preferably 2.0 to 40 g / m ² , and more preferably 13 to 40 g / m ² in the nonvolatile resin coating liquid containing the reinforcing resin. If the non-volatile coating amount is less than 2.0 g / m ² , sufficient reinforcement may not be performed. When the coating amount of the non-volatile component is more than 40 g / m ² , the thickness of the reinforcing resin increases, and when the master is wound up in a roll shape, a step is generated and wrinkles occur, or the smoothness of the film surface is impaired. The contact property with the thermal head at the time of drilling may be reduced, leading to poor drilling.

  The width of the reinforcing resin is preferably 5 to 10 mm. When the reinforcing width is less than 5 mm, a sufficient reinforcing effect by the reinforcing resin may not be obtained. When the reinforcing width exceeds 15 mm, the reinforcing resin is applied to the print image range, which may adversely affect the print image quality.

  The reinforcing resin preferably has a bending stiffness of 20 to 200 mN. When the bending stiffness is less than 20 mN, the reinforcing effect by the reinforcing resin cannot be obtained, and the transportability may not be improved. The bending stiffness is sufficient if it is 200 mN, and if it exceeds this, the cost may be wasted.

  The method of providing the reinforcing resin is not particularly limited, but it is easy to reinforce without changing the thickness of the master. Therefore, after applying the reinforcing resin coating solution containing the reinforcing resin, it is provided by either drying or curing It is preferable.

-Porous fiber membrane-
The porous fiber membrane is preferably provided because the bending stiffness of the reinforcing resin is improved by providing the porous fiber membrane on the porous resin membrane.
The porous fiber membrane is not particularly limited as to the material, size, structure, etc., and can be appropriately selected from known materials according to the purpose. Examples of the material include glass, sepiolite, and various types. Mineral fibers such as metals; animal fibers such as wool and silk; natural fibers such as cotton, manila hemp, mulberry, mitsumata, and pulp; recycled fibers such as sufu and rayon; synthetic fibers such as polyester, polyvinyl alcohol, and acrylic; carbon fibers A semi-synthetic fiber; a thin paper such as an inorganic fiber having a whisker structure. Among these, a porous fiber membrane obtained by mixing natural fibers and synthetic fibers, and a porous fiber membrane consisting only of synthetic fibers are preferable. The porous fiber membrane obtained by mixing natural fibers and synthetic fibers is relatively inexpensive and can provide good ink permeability and bending stiffness. The porous fiber membrane made of only synthetic fibers is preferable because it is less dependent on the environment such as mechanical strength and charging characteristics, and finer fibers than natural fibers can be obtained.

The thickness (for example, diameter), length, and shape of the fibrous material constituting the porous fiber membrane is not particularly limited, and is appropriately selected according to the perforated diameter of the thermoplastic resin film, the thickness of the film, and the like. be able to.
As a diameter (thickness) of the said fibrous substance, 20 micrometers or less are preferable and 1-10 micrometers is more preferable. If the diameter is less than 1 μm, the tensile strength may be weakened. If the diameter is more than 20 μm, ink passage may be hindered and a white-out image due to fibers may occur.
The length of the fibrous substance is preferably 0.1 to 10 mm, and more preferably 1 to 6 mm. If the length of the fibrous material is less than 0.1 mm, the tensile strength may be weakened, and if it exceeds 10 mm, it may be difficult to uniformly disperse.

There is no restriction | limiting in particular as basic weight of the said porous fiber membrane, According to the objective, it can select suitably, 1-20 g / m < ² > is preferable and 3-10 g / m < ² > is more preferable. When the basis weight exceeds 20 g / m ² , the ink permeability decreases and the image sharpness may decrease. When the basis weight is less than 1 g / m ² , sufficient strength as an ink-permeable support is obtained. It may not be obtained.

  The porous fiber membrane may be a commercially available product or an appropriately formed one. The method for forming the porous fiber membrane is not particularly limited and may be appropriately selected depending on the purpose. For example, the porous fiber membrane may be a paper-making paper obtained by wet-making short fibers, a nonwoven fabric or a woven fabric. Any of these may be used, and a screen basket may be used, and among these, papermaking paper is preferable from the viewpoint of productivity and cost. Moreover, as a method of forming the porous fiber membrane, it can be formed by the method described in JP-B-49-18728, JP-B-49-8809, and the like.

  The method for laminating the porous fiber film and the porous resin film and the thermoplastic resin film is not particularly limited and may be appropriately selected depending on the intended purpose. For example, one surface of the thermoplastic resin film It is preferable to apply a porous resin film coating liquid on the top, and at least the outermost surface layer of the porous resin film is dried and formed into a film, and then bonded to the porous fiber layer coated with an adhesive. If a porous fiber film is laminated before the porous resin film is formed, the formation of the porous resin film may be hindered and a desired porous resin film may not be obtained. Moreover, since there exists a possibility that the said adhesive agent may block | close the hole of a porous resin film, it is more preferable to apply | coat to the porous fiber film.

As an adhesive used when laminating (laminating) the porous fiber film and the film having the porous resin film, the adhesive does not block the pores of the porous resin film from the aspect of ink permeability. The thing of the state of a viscosity is preferable. The viscosity until the adhesive is completely cured is preferably 100 cP or more, more preferably 300 cP or more at 25 ° C.
In this case, if a solvent-type adhesive is used as the adhesive, the porous resin film is eroded and the pores are blocked. Therefore, there is no solvent at least when the porous resin film and the porous fiber film are laminated. From this point, a solventless type adhesive, a water-based or emulsion type adhesive is preferably used.

The method for applying the adhesive is not particularly limited and may be appropriately selected depending on the purpose. For example, (1) a coating solution diluted with an organic solvent such as ethyl acetate is applied to the porous fiber layer. Then, after drying, a method of bonding with a porous resin film, (2) a method of applying without solvent, and the like are mentioned. Among these, (2) A method of coating without solvent is preferred.
The method for applying the adhesive is not particularly limited and may be appropriately selected depending on the purpose. For example, blade coating method, reverse roll coating method, gravure coating method, knife coating method, spray coating method, offset gravure Preferred examples include a coating method, a kiss coating method, a bar coating method, and the like.
The surface on which the adhesive is applied may be applied to either the porous resin film or the porous fiber film. However, in order not to block the opening of the porous resin film, the surface is applied to the porous fiber film. It is preferable to work.

  As the adhesive, a polyurethane-based adhesive is particularly preferable in order to obtain a predetermined adhesive strength and satisfy the above conditions. As the polyurethane-based adhesive, a solventless polyurethane adhesive capable of obtaining desired adhesive strength with a low adhesion amount is suitable. In addition, since the porous fiber membrane preferably contains inexpensive natural fibers as described above, in this case, the aqueous fiber or emulsion type polyurethane adhesive causes expansion and contraction of the porous fiber membrane during coating, A solventless polyurethane adhesive is also preferably used from the viewpoint of deteriorating curl and the like.

  The solventless polyurethane adhesive is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, (1) one-component moisture curing obtained by reaction of a polyol component and an isocyanate component Type urethane prepolymer, (2) two-component curable adhesive divided into a polyol component and an isocyanate component, and the like.

  The polyol component is not particularly limited as long as it has a hydroxyl group at both ends and is a liquid, and can be appropriately selected from known ones according to the purpose. For example, a polyether polyol having hydroxyl groups at both ends , Polyester polyol, and the like.

  Examples of the isocyanate component include hexamethylene diisocyanate (HMDI), 2,4-diisocyanate-1-methylcyclohexane, 2,6-diisocyanate-1-methylcyclohexane, diisocyanate cyclobutane, tetramethylene diisocyanate, o-, m- and p-xylylene diisocyanate (XDI), dicyclohexylmethane diisocyanate, dimethyldicyclohexylmethane diisocyanate, hexahydrometaxylidene diisocyanate (HXDI), lysine diisocyanate alkyl ester (the alkyl part of the alkyl ester has 1 to 6 carbon atoms) Aliphatic or cycloaliphatic diisocyanates; toluylene-2,4-diisocyanate (TDI), toluylene- , 6-diisocyanate, diphenylmethane-4,4′-diisocyanate (MDI), 3-methyldiphenylmethane-4,4′-diisocyanate, m- and p-phenylene diisocyanate, chlorophenylene-2,4-diisocyanate, naphthalene-1, Aromatics such as 5-diisocyanate, diphenyl-4,4′-diisocyanate, 3,3′-dimethyldiphenyl-4,4′-diisocyanate, 1,3,5-triisopropylbenzene-2,4-diisocyanate, diphenyl ether diisocyanate And diisocyanates, and mixtures thereof. These may be used individually by 1 type and may use 2 or more types together.

  When applying a solvent-free polyurethane adhesive to the porous fiber membrane, if the viscosity is too high, the fibers will fall off and a coating failure will occur, so it is possible to apply the coating by lowering the viscosity by heating the roll. preferable. The viscosity of the solventless polyurethane adhesive is preferably 3000 cP or less, more preferably 300 to 1500 cP at 25 ° C. If the viscosity is less than 3000 cP, the opening may be blocked after bonding with the porous resin film to impair ink permeability, and the fiber layer is likely to fall off.

  When the solventless adhesive is used, curing is preferably performed for the purpose of promoting the reaction of the heat-sensitive stencil master wound in a roll. The curing temperature is preferably 50 ° C. or lower, and more preferably 40 ° C. or lower. When the temperature of the curing exceeds 50 ° C., the thermoplastic resin film may shrink and a curling problem may occur. The curing time is not particularly limited as long as the desired adhesive force can be obtained, and can be appropriately selected according to the purpose.

  As a method for applying the adhesive, there is a method in which a coating liquid diluted with an organic solvent such as ethyl acetate is applied to the porous fiber layer and dried, and then bonded to the porous resin film. From the problem of residual solvent, a method of coating without solvent is preferred.

Unlike the conventional heat-sensitive stencil printing master (laminated product of thermoplastic resin film and porous fiber film), it is not necessary to consider the influence of perforation inhibition as the adhesion amount of the adhesive. Is not particularly limited as long as the pores of the porous resin membrane and the porous fiber membrane are not blocked, and can be appropriately selected according to the purpose, preferably 0.05 to 5.0 g / m ^2. , 0.1 to 3.0 g / ^{m 2} is more preferable.

The adhesive strength between the thermoplastic resin and the porous resin film and the adhesive strength between the porous resin film and the porous fiber film in the heat-sensitive stencil printing master of the present invention is preferably 1.4 N / m or more. 8 N / m or more is more preferable.
When the adhesive strength is less than 1.4 N / m, film peeling between the porous resin film and the porous fiber film occurs during handling and transportation, which not only causes wrinkles, but also prevents the master from being damaged during printing. May cause problems such as elongation, tearing and tearing. The upper limit of the adhesive strength is not particularly limited as long as ink passage is not inhibited, and can be appropriately selected according to the purpose.

  The surface on which the adhesive is applied may be applied to either a porous resin film or a porous fiber film. However, in order not to block the opening of the porous resin film, it is applied to the porous fiber film. Is good.

--Conductive material--
The porous fiber membrane preferably has a conductive material because charging during conveyance in a printing press is suppressed and conveyance jam is unlikely to occur.
Here, in the present invention, the conductive substance may be a conductive substance as a result of the fact that a substance that does not originally have conductivity contains an antistatic agent. Further, the conductive substance may be the antistatic agent itself, and the conductive substance may further contain an antistatic agent for improving the performance.

  The conductive substance is not particularly limited as long as it can impart conductivity to the laminate, and can be appropriately selected from known ones according to the purpose. For example, an electron beam curable resin UV curable resin, conductive powder, surfactant, a mixture of a low molecular surfactant and a binder resin, an ionic polymer compound, or a mixture thereof. Among these, since it is a liquid, it is easy to apply, and since it crosslinks and solidifies when irradiated with an electron beam or ultraviolet rays, it has no deterioration in antistatic performance due to movement and is excellent in stability over time. A curable resin or an ultraviolet curable resin is preferred.

The electron beam curable resin or the ultraviolet curable resin is not particularly limited as long as it is a polymer having conductivity, and can be appropriately selected from known ones according to the purpose. A resin having a bond or a hydrophilic group is suitable, for example, a relatively low molecular weight polyester resin, polyether resin, acrylic resin, epoxy resin, urethane resin, (meth) acrylate and a radically polymerizable monofunctional monomer or polyfunctional. And a copolymer with a monomer. The resin having a hydrophilic group in the structure has a characteristic of obtaining electrical conductivity when the hydrophilic group adsorbs moisture.
Since these resins are liquid before being irradiated with an electron beam or ultraviolet rays, they are less likely to solidify during coating and contaminate the coating equipment. Also, solventless coating with a low environmental load is possible.

  Examples of the electron beam curable resin or ultraviolet curable resin include polyurethane acrylate resin, polyester acrylate resin, rosin-modified urethane / ester acrylate resin, water-soluble epoxy acrylate resin, and self-emulsifiable polyurethane acrylate resin. Among these, a water-soluble epoxy acrylate resin and a self-emulsifiable polyurethane acrylate resin are preferable because they can be diluted with water and are easy to handle.

  Further, when crosslinking is performed by ultraviolet irradiation, a photopolymerization initiator is preferably contained. There is no restriction | limiting in particular as this photoinitiator, It can select suitably according to the objective from well-known things, For example, a monofunctional photoinitiator or a polyfunctional photoinitiator is used. . These may be used individually by 1 type and may use 2 or more types together.

  Examples of the monofunctional photopolymerization initiator include 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl acryloyl phosphate, tetrahydrofurfuryl acrylate, tetrahydrofurfuryl acrylate, tetrahydro And acrylates of full-freele derivatives.

  Examples of the polyfunctional polymerization initiator include dicyclobenenyl acrylate, dicyclobenenyl oxyethyl acrylate, 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, and 1,6-hexanediethyl. Earl diacrylate, diethylene glycol diacrylate, neoventil glycol 400 diacrylate, polyethylene glycol 400 diacrylate, hydroxybivalate ester neoventyl glycol diacrylate, tripropylene glycol diacrylate, 1,3-bis (3'-acrylic Oxyethoxy-2'-hydroxypropyl) -5,5-dimethylhydantoin, hydroxybivalate ester neobenchyl glycol diacrylate, trimethylolpropane tria Relate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, and the like.

  In the case of curing by irradiation with the electron beam, various electron beam accelerators such as a Cockloft Walton type, a bandegraph type, a resonance transformation type, an insulating core transformer type, a linear type, an electrocurtain type, a dynamitron type, a high frequency type, etc. The irradiation energy of the electron beam is preferably 50 to 1000 keV, more preferably 100 to 300 keV.

  In the case of curing by ultraviolet irradiation, it is preferable to use a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, a metal halide lamp, or an electrodeless discharge lamp D bulb. Among these, a metal halide lamp or an electrodeless discharge lamp D bulb having a continuous wavelength between emission wavelengths of 320 to 450 nm is preferable in terms of a high curing rate.

In addition, since irradiation with an electron beam or ultraviolet rays raises the ambient temperature and the thermoplastic resin film may shrink, it is preferable to cool using a cooling device or the like.
The porous fiber film coated with the conductive material coating solution and cured by electron beam irradiation or ultraviolet irradiation is dried with a dryer or the like. The drying temperature is preferably 40 to 70 ° C. If the drying temperature exceeds 70 ° C, the thermoplastic resin film may shrink, and if it is less than 40 ° C, it may take time to dry the thermoplastic resin film.

The conductive substance may contain an ionic polymer compound. Many of the ionic polymer compounds are water-soluble, and when they are water-soluble, they have little impact on the environment, are easy to handle, are coated with a coating solution containing a reinforcing resin, and are simply dried. Therefore, the master manufacturing method can be simplified. Furthermore, in the master using the ionic polymer compound, bending stiffness, transportability in the printing press, and wrinkle suppression effect are improved.
The ionic polymer compound is not particularly limited and may be appropriately selected from known compounds according to the purpose. For example, lithium salt, sodium salt, potassium salt, olefin of isoprenesulfonic acid copolymer -Anionic polymer compounds such as lithium salt, sodium salt and potassium salt of maleic acid copolymer; Cationic polymer compounds such as quaternary ammonium ion modified acrylic resin and quaternary ammonium ion modified urethane resin . Among these, isoprene sulfonic acid copolymer sodium salt and olefin / maleic acid copolymer sodium salt are particularly preferable because of high antistatic effect. These may be used individually by 1 type and may use 2 or more types together. These are preferably used because of their higher antistatic performance than carboxylates among anionic polymer compounds.

  As the conductive substance, it is also preferable to use conductive powder from the viewpoint that the antistatic performance does not deteriorate with time and there is no environmental influence. There is no restriction | limiting in particular as this electroconductive powder, According to the objective, it can select suitably according to the objective, For example, metal powders, such as aluminum, iron, zinc, tin; Tin oxide, antimony oxide, indium oxide And metal oxide powders such as carbon black. These may be used individually by 1 type and may use 2 or more types together.

The conductive powder is used in combination with a binder resin. On the other hand, the surfactant as the conductive substance may be used alone or in combination with a binder resin as necessary.
There is no restriction | limiting in particular as this binder resin, According to the objective, it can select suitably according to the objective, For example, application to a porous fiber membrane like an electron beam curable resin or an ultraviolet curable resin, etc. It is sometimes preferable to use a liquid which is then solidified by electron beam irradiation or ultraviolet irradiation. The electron beam curable resin or the ultraviolet curable resin can be appropriately selected from those described above according to the purpose. In addition, although the said binder resin does not need to have electroconductivity, it is preferable that it has electroconductivity at the point which the antistatic effect increases.

A surfactant can also be used as the conductive substance. There is no restriction | limiting in particular as this surfactant, Although it can select suitably according to the objective from well-known things, It is preferable that it is a low molecular surfactant.
When the conductive substance is a combination of a low molecular surfactant and a binder resin, the liquid conductive substance and the resin are mixed, and even if the conductive substance on the resin surface is removed, the resin The conductive material oozes out from the inside, and it becomes possible to obtain a high temporal stability compared to the case of single coating.
The low molecular surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, sorbitan sesquioleate, alkyldimethylethylammonium ethosulphate, alkyl phosphate monoethanolamine, alkyldimethylamino Examples include betaine acetate, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan sesquistearate, sorbitan monooleate, and the like.

  The state of adhesion of the conductive substance is not particularly limited, whether it is in a liquid state or a solid state, but is preferably adhered to the porous fiber membrane in a solid state. In the final master for heat-sensitive stencil printing, the conductive material only needs to be in a solid state, and the conductive material may be liquid when applied to the porous fiber membrane. There is no restriction | limiting in particular as a method of solidifying the electrically conductive substance which was liquid at the time of providing, According to the objective, it can select suitably, For example, drying, a chemical change, etc. are mentioned.

In the heat-sensitive stencil printing master of the present invention, a stick prevention layer can be provided on the opposite surface of the thermoplastic resin film on which the porous resin film and the porous fiber film are formed to prevent sticking with the thermal head. .
The stick preventing agent in the stick preventing layer is not particularly limited and can be appropriately selected according to the purpose from those generally used in conventional heat-sensitive stencil printing masters. For example, a silicone release agent , Fluorine release agents, phosphate ester surfactants, and the like. An antistatic agent can be added to the anti-stick layer in order to prevent generation of static electricity.

  The method for forming the stick prevention layer is not particularly limited and can be appropriately selected according to the purpose.For example, a roll coater, a gravure coater, a reverse coater, a bar coater or the like diluted with water or a solvent is used. An anti-stick layer can be formed by applying and drying.

(Method for manufacturing a master for thermal stencil printing)
The method for producing a master for heat-sensitive stencil printing of the present invention comprises a porous resin film forming step of forming a porous resin film by applying a coating liquid for forming a porous resin film on a thermoplastic resin film and drying it. In addition, it further includes other steps such as a reinforcing resin coating step and, if necessary, a conductive substance coating step and a porous fiber membrane coating step.

-Porous resin film formation process-
The porous resin film forming step is a step of forming a porous resin film by applying a porous resin film-forming coating solution containing a porous resin on a thermoplastic resin film and drying it.
The porous resin film coating solution contains at least a resin and further contains other components as required, and is preferably a water-in-oil type.

  As the method for forming the porous resin film, as described above, the first formation method (see Japanese Patent Laid-Open No. 10-24667), the second formation method (see Japanese Patent Laid-Open No. 11-235858), or the like. Is mentioned.

As the method for forming the porous resin film, there is a method of forming a porous resin film by further applying a water-in-oil emulsion containing a dissolved porous resin onto a thermoplastic resin film and drying it. preferable. With this method, the pore diameter uniformity of the porous resin film is high, and the thermal head is highly pierced, so the image quality is excellent, there is little set-off, and there is no occurrence of jamming on the drum or wrinkles on the drum. The master which has the feature of it can be manufactured efficiently.
Moreover, since the shape of the obtained porous resin film does not depend on the solubility of the resin, it is less affected by temperature and humidity, and is excellent in that the formed film shape is highly reproducible. Furthermore, since the degree of freedom of the formulation is high and the range in which the porous resin film can be formed is wide, it is excellent in that the range in which the viscosity of the coating solution can be adjusted by the ratio of the oil phase / water phase, the resin concentration, the resin molecular weight, and the like.

-Reinforcing resin application process-
In the reinforcing resin coating step, the reinforcing resin coating liquid containing the above-described reinforcing resin is applied to both ends of the porous resin film on the thermoplastic film, and then provided by either drying or curing.

As described above, the non-volatile total coating amount of the reinforcing resin coating liquid is preferably 2.0 to 40 g / m ² . When the non-volatile total coating amount is in the above range, a sufficient transportability improvement effect can be obtained, and the perforation sensitivity is not affected.

-Conductive substance application process-
The conductive substance applying step is a step of applying a conductive substance coating solution containing at least a conductive substance to the reinforcing resin.
As described above, the conductive substance includes at least one of an electron beam curable resin and an ultraviolet curable resin, a surfactant, a mixture of a low molecular surfactant and a binder resin, a conductive powder, and ions. It is preferable that it is at least 1 sort (s) selected from a conductive polymer compound.

-Porous fiber membrane formation process-
The porous fiber membrane forming step is a step of forming a porous fiber membrane on the porous resin membrane.
The method for forming the porous fiber membrane is not particularly limited and may be appropriately selected depending on the purpose. As described above, the porous fiber membrane may be a paper-making paper obtained by wet-making short fibers, or may be a nonwoven fabric or a woven fabric. It may be a screen basket or the like, and papermaking paper is preferably used from the viewpoint of productivity and cost.

  Furthermore, there is no restriction | limiting in particular as another process, According to the objective, it can select suitably, For example, a stick prevention layer formation process etc. are mentioned.

  The heat-sensitive stencil master produced by the method for producing a heat-sensitive stencil master of the present invention does not lose the characteristics of excellent image quality and little set-off without losing the punching ability by the thermal head, There is no generation of jam or wrinkles on the drum due to static electricity in the printing press, and it is a high-quality one that can solve conventional problems.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Preparation of coating solution for forming porous resin film>
After stirring and dispersing 1 part by mass of talc (manufactured by Nippon Talc Co., Ltd., Microace LG) in 30 parts by mass of ethyl acetate, 3 parts by mass of polyvinyl acetal resin (Sekisui Chemical Co., Ltd., ESREC KS1) was dissolved. . In this solution, 0.1 part by mass of sorbitan fatty acid ester (Nikko Chemicals Co., Ltd., SO-15), 0.1 part by mass of modified silicone oil (Shin Super Chemical Co., Ltd., KF6012), and acrylic polymer O / W 0.2 parts by mass of a type emulsion (Joncry-711, manufactured by Johnson Polymer Co., Ltd.) was stirred and dissolved. While stirring this solution, 25 parts by mass of a 1% by weight aqueous solution of hydroxyethyl cellulose (HEC) (manufactured by Wako Pure Chemical Industries, Ltd., using hydroxyethyl cellulose) was added dropwise to prepare a water-in-oil emulsion. This water-in-oil emulsion was used as a coating solution for forming a porous resin film.

<Preparation of reinforcing resin coating solution>
Reinforcing coating liquid 1:
A non-volatile component concentration 29 mass% reinforcing coating solution 1 of an O / W type polyester emulsion (manufactured by Chukyo Yushi Co., Ltd., Resem ES-1) was prepared.
Reinforcing coating solution 2:
A coating solution 2 for reinforcing a non-volatile content of 34% by mass of an O / W type polyvinyl butyral emulsion (manufactured by Chukyo Yushi Co., Ltd., Resem VB-2) was prepared.
Reinforcing coating solution 3:
A reinforcing coating solution 3 having a nonvolatile content concentration of 70% by mass of an electron beam curable resin polyoxyethylene monoacrylate aqueous solution was prepared.
Reinforcing resin coating solution 4:
A reinforcing coating solution 4 having a nonvolatile content concentration of 40% by mass of an O / W type carnauba wax emulsion (manufactured by Sanai Oil Co., Ltd.) was prepared.

<Preparation of porous fiber membrane>
Porous fiber membrane 1:
40 parts by mass of unstretched polyester fiber (Teijin Co., Ltd., Tepyrus TK08PN) having a fineness of 0.2 denier and a fiber length of 3 mm, and a polyester binder fiber having a fineness of 1.5 denier and a fiber length of 5 mm (sheath component: low melting point PET, heat Melting temperature 110 ° C., core component: PET / Unitika Co., Ltd., Melty 4080) 60 parts by mass were mixed, and porous fiber membrane 1 was produced with a circular net paper machine.
The obtained porous fiber membrane had a basis weight of 6.0 g / m ² and a thickness of 20 μm.
Porous fiber membrane 2:
40 parts by mass of unstretched polyester fiber having a fineness of 0.2 denier and a fiber length of 3 mm (manufactured by Teijin Co., Ltd., Tepyrus TK08PN), a polyester binder fiber having a fineness of 1.5 denier and a fiber length of 5 mm (sheath component: low melting point PET, heat Melting temperature 110 ° C., core component: PET / Unitika Co., Ltd., Melty 4080) was mixed with 60 parts by mass, and a porous fiber membrane was produced by a circular net paper machine.
The obtained porous fiber membrane 2 had a basis weight of 10 g / m ² and a thickness of 30 μm.

<Preparation of electron beam curable adhesive>
50 parts by mass of polyurethane acrylate resin (Arakawa Chemical Industries, Ltd., beam set 504H) and 50 parts by mass of acrylic acid ester monomer (Toa Gosei Co., Ltd., Aronix M-101) are melt-mixed at about 80 ° C. A line curable adhesive was prepared.

<Preparation of anti-stick agent coating solution>
A stick prevention layer coating solution consisting of 1 part by mass of silicone oil (SF 8422 manufactured by Toray Dow Corning Co., Ltd.) and 99 parts by mass of toluene was prepared.

Example 1
−Preparation of heat-sensitive stencil printing master−
The porous resin film-forming coating solution is applied to a biaxially stretched polyester film having a thickness of 2 μm with a gravure roll, dried at 50 ° C., and a porous resin having an adhesion amount after drying of 5 g / m ^2. A film was formed.
Subsequently, with a gravure roll, the porous resin film is brought into contact with both end portions substantially parallel to the transport direction (longitudinal direction) and has a width of 10 mm and the same thickness as the porous resin film. Thus, the reinforcing resin coating solution 1 was applied and dried at 50 ° C. The total coating amount of the nonvolatile component of the reinforcing resin coating solution 1 after drying was 12 g / m ² . In addition, the non-volatile total coating amount of the reinforcing resin coating liquid is obtained by calculating a mass difference between the porous resin film 25 cm × 25 cm to which the reinforcing resin coating liquid is applied and the porous resin film not applied to g / m ² . The converted amount was defined as the total amount of nonvolatile content applied.
Furthermore, using the bar coater on the surface of the thermoplastic resin film (the surface opposite to the surface on which the porous resin film was laminated), the amount of adhesion after drying was 0.05 g / m ² . This was applied and dried to form a stick prevention layer.
Thus, the heat-sensitive stencil master for Example 1 was produced.

(Example 2)
−Preparation of heat-sensitive stencil printing master−
In Example 1, a heat-sensitive stencil printing master of Example 2 was prepared in the same manner as in Example 1 except that the reinforcing resin coating liquid 2 was applied in a 16 mm width instead of the reinforcing resin coating liquid 1. In addition, when the total application amount of the non-volatile content of the reinforcing resin coating solution 2 after drying was measured in the same manner as in Example 1, it was 15 g / m ² .

(Example 3)
−Preparation of heat-sensitive stencil printing master−
The porous resin film-forming coating solution is applied to a biaxially stretched polyester film having a thickness of 2 μm with a gravure roll, dried at 50 ° C., and a porous resin having an adhesion amount after drying of 5 g / m ^2. A film was formed.
Subsequently, using a roll coater heated to 80 ° C., the electron beam curable adhesive was applied to one surface of the porous fiber membrane 1 so that the adhesion amount was 0.4 g / m ² . The surface coated with the adhesive and the porous resin film were laminated.
Further, the porous resin film and the porous fiber film are in contact with both end portions substantially parallel to the conveyance direction (longitudinal direction), have a width of 4 mm, and a thickness combined with the porous resin film and the porous fiber film. Reinforcing resin coating solution 3 was applied so as to have the same thickness as in Example 1, and dried at 50 ° C. When the total coating amount of the nonvolatile component of the reinforcing resin coating solution 3 after drying was measured in the same manner as in Example 1, it was 42 g / m ² .
Subsequently, an electron beam of 5 Mrad was irradiated to cure the electron beam curable adhesive and polyoxyethylene monoacrylate.
Furthermore, using the bar coater on the surface of the thermoplastic resin film (the surface opposite to the surface on which the porous resin film was laminated), the amount of adhesion after drying was 0.05 g / m ² . This was applied and dried to form a stick prevention layer.
Thus, a heat-sensitive stencil printing master of Example 3 was produced.

Example 4
−Preparation of heat-sensitive stencil printing master−
In Example 3, a master for thermal stencil printing of Example 4 was prepared in the same manner as in Example 3 except that the reinforcing resin coating liquid 4 was applied in a width of 6 mm instead of the reinforcing resin coating liquid 3. In addition, when the total application amount of the non-volatile component of the reinforcing resin coating solution 4 after drying was measured in the same manner as in Example 1, it was 1.9 g / m ² .

(Example 5)
−Preparation of heat-sensitive stencil printing master−
In Example 4, the master for thermal stencil printing of Example 5 was produced like Example 4 except having applied the reinforcement resin coating liquid 1 instead of the reinforcement resin coating liquid 4. FIG. In addition, when the total application amount of the non-volatile content of the reinforcing resin coating solution 4 after drying was measured in the same manner as in Example 1, it was 35 g / m ² .

(Example 6)
−Preparation of heat-sensitive stencil printing master−
In Example 1, in place of the reinforcing resin coating liquid 1, except that the reinforcing resin is provided by applying the porous resin film-forming coating liquid so as to have a thickness of 25 μm. Similarly, the master for heat-sensitive stencil printing of Example 6 was produced. The total coating amount of the nonvolatile component of the coating solution for forming a porous resin film used as the reinforcing resin after drying was measured in the same manner as in Example 1 and found to be 8 g / m ² .

(Example 7)
−Preparation of heat-sensitive stencil printing master−
In Example 2, a heat-sensitive stencil printing master of Example 7 was produced in the same manner as in Example 2 except that the reinforcing resin coating solution 2 was applied in a width of 14 mm. In addition, when the total application amount of the non-volatile content of the reinforcing resin coating solution 2 after drying was measured in the same manner as in Example 1, it was 15 g / m ² .

(Example 8)
−Preparation of heat-sensitive stencil printing master−
In Example 3, a heat-sensitive stencil printing master of Example 8 was produced in the same manner as in Example 3 except that the reinforcing resin coating solution 3 was applied with a width of 7 mm. In addition, when the total application amount of the nonvolatile component of the reinforcing resin coating solution 3 after drying was measured in the same manner as in Example 3, it was 38 g / m ² .

(Comparative Example 1)
−Preparation of heat-sensitive stencil printing master−
In Example 1, a heat-sensitive stencil printing master of Comparative Example 1 was produced in the same manner as in Example 1 except that no reinforcing resin was provided.

(Comparative Example 2)
−Preparation of heat-sensitive stencil printing master−
In Example 3, a heat-sensitive stencil printing master of Comparative Example 2 was produced in the same manner as in Example 3 except that no reinforcing resin was provided.

(Comparative Example 3)
−Preparation of heat-sensitive stencil printing master−
A heat-sensitive stencil printing master of Comparative Example 3 was produced in the same manner as in Comparative Example 2, except that the porous fiber membrane 1 was replaced with the porous fiber membrane 2 in Comparative Example 2.

(Comparative Example 4)
−Preparation of heat-sensitive stencil printing master−
Using the roll coater heated at 25 degreeC, the said electron beam curable adhesive was apply | coated to one surface of the porous fiber membrane 2 so that the adhesion amount might be 0.4 g / m < ² >. The surface to which the adhesive was applied and a biaxially stretched polyester film having a thickness of 2 μm were laminated, and an electron beam of 5 Mrad was irradiated to cure the electron beam curable adhesive.
Subsequently, the reinforcing resin is in contact with both ends of the porous fiber membrane substantially parallel to the transport direction (longitudinal direction) so as to have a width of 10 mm and the same thickness as the porous fiber membrane. Coating solution 1 was applied and dried at 50 ° C. In addition, when the total application amount of the nonvolatile component of the reinforcing resin coating solution 1 after drying was measured in the same manner as in Example 1, it was 12 g / m ² .
Furthermore, using the bar coater on the surface of the thermoplastic resin film (the surface opposite to the surface on which the porous resin film was laminated), the amount of adhesion after drying was 0.05 g / m ² . This was applied and dried to form a stick prevention layer.
Thus, a heat-sensitive stencil printing master of Comparative Example 4 was produced.

(Comparative Example 5)
In Example 1, instead of applying the reinforcing resin coating solution 1 in contact with both ends of the porous resin film substantially parallel to the transport direction (longitudinal direction), the porous resin film is spaced at intervals of 50 cm. A heat-sensitive stencil printing master of Comparative Example 5 was produced in the same manner as in Example 1 except that the reinforcing resin coating solution 1 was applied along the short direction of the porous resin film. In addition, when the total application amount of the nonvolatile component of the reinforcing resin coating solution 1 after drying was measured in the same manner as in Example 1, it was 12 g / m ² .

-Evaluation-
Next, various characteristics of each of the heat-sensitive stencil printing masters of Examples 1 to 8 and Comparative Examples 1 to 5 prepared above were evaluated as follows. The results are shown in Table 1.

<Measurement of bending stiffness>
L & W STIFFNESS TESTER for the reinforcing resin in each of the heat-sensitive stencil printing masters of Examples 1 to 8 and Comparative Examples 4 and 5 and the conveyance direction (longitudinal direction) ends of each of the heat-sensitive stencil printing masters of Comparative Examples 1 to 3 (AB Lorentzen Co., 16-D) was used to set the bending angle = 30 ° and the bending length = 1 mm, and the bending stiffness in the transport direction (longitudinal direction) was measured.

<Evaluation of transportability>
About each heat-sensitive stencil printing master of Examples 1-8 and Comparative Examples 1-5, plate-making conveyance is carried out using a printing machine (Ricoh Co., Ltd., Ricoh Satellite A400) in an environment of 23 ° C.-65% RH. When wound around the drum, a test was conducted to determine whether or not the drum would be wound straight without skewing, and the following criteria were evaluated.
〔Evaluation criteria〕
○: The master was successfully wound around the drum.
Δ: Although the behavior of the master is slightly unstable, the master is normally wound around the drum and there is no practical problem.
X: The master was wound around the drum diagonally or wrinkled.

<Evaluation of white spots on printed images>
Using a Satellite A400 (made by Ricoh Co., Ltd .: equipped with a thermal head manufactured by Toshiba Corporation) as a perforation and printing apparatus, each of the thermal stencil printing masters of Examples 1 to 8 and Comparative Examples 1 to 5 was made with an A3 size solid chart and Printing was done. About the obtained printed image, the degree of white spot of the printed image was evaluated according to the following criteria.
〔Evaluation criteria〕
◯: There are almost no white spots in the printed image.
Δ: Slight white spots are observed in the printed image, but there is no practical problem.
×: White spots that may be caused by poor conveyance occurred.

＊Ｆ＋Ｐ：熱可塑性樹脂フィルム（Ｆ）上に多孔性樹脂被膜（Ｐ）を積層したもの
＊Ｆ＋Ｐ＋Ｔ：熱可塑性樹脂フィルム（Ｆ）上に多孔性樹脂被膜（Ｐ）、多孔性繊維膜（Ｔ）をこの順に積層したもの
＊Ｆ＋Ｔ：熱可塑性樹脂フィルム（Ｆ）上に多孔性繊維膜（Ｔ）を積層したもの

* F + P: A laminate of a porous resin film (P) on a thermoplastic resin film (F) * F + P + T: A porous resin film (P) and a porous fiber film (T) on a thermoplastic resin film (F) * F + T: Laminated porous fiber membrane (T) on thermoplastic resin film (F)

From the results of Table 1, each of Examples 1 to 8 having reinforcing resins at both ends in the transport direction has excellent transportability to the extent that there is no practical problem, and a high-quality image can be recorded. .
Furthermore, in Examples 1-5, 7 and 8 using a water-in-oil (O / W) emulsion resin or an electron beam curable resin as the reinforcing resin, the image has better transportability and has high image quality. Was recorded.
In particular, in Examples 5, 7, and 8 in which the coating amount of the reinforcing resin coating liquid, the bending stiffness, and the width of the reinforcing resin are within the predetermined ranges, images having extremely excellent transportability and higher image quality can be obtained. I was able to record.
In Comparative Examples 1 and 2, since there was no reinforcing resin, the transportability was poor, and white spots in the printed image were also observed.
Comparative Example 3 used a highly weighed porous fiber membrane, so that the transportability was good, but white spots were seen in the printed image.
In Comparative Example 4, since there was no porous resin film (low continuity in the lateral direction of the voids), the reinforcing resin partially protruded into the printed image portion and white spots occurred.
In Comparative Example 5, the bending stiffness in the master transport direction was not improved, and the transportability was not improved.

  The master for heat-sensitive stencil printing of the present invention does not lose the characteristics of excellent image quality and low set-off without impairing the punchability by the thermal head, and also on the jam or drum due to static electricity in the master printer. There is no generation of wrinkles, it has excellent transportability, and is suitably used as a master for heat-sensitive stencil printing.

FIG. 1 is a schematic cross-sectional view showing an example of the master for heat-sensitive stencil printing according to the present invention, which has a porous resin film and a reinforcing resin on a thermoplastic resin film. FIG. 2 is a schematic cross-sectional view showing an example of the master for heat-sensitive stencil printing of the present invention, which has a porous resin film and a porous fiber film in this order, and a reinforcing resin is provided on the porous resin film and the porous fiber film. It is arranged.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thermoplastic resin film 2 Porous resin film 3 Reinforcement resin 4 Porous fiber film

Claims (12)

  A thermoplastic resin film; a porous resin film on at least one surface of the thermoplastic resin film; and a reinforcing resin disposed in contact with both ends of the porous resin film. A master for heat sensitive stencil printing.   The heat-sensitive stencil printing master according to claim 1, wherein the reinforcing resin is disposed at both ends substantially parallel to the conveyance direction of the master.   The thermal printing master according to claim 1, wherein the thickness of the porous resin film is equal to the thickness of the reinforcing resin.   The master for heat-sensitive stencil printing according to any one of claims 1 to 3, comprising a porous fiber film on the porous resin film.   The heat-sensitive stencil printing master according to any one of claims 1 to 4, wherein the reinforcing resin is a water-in-oil (O / W) emulsion resin.   The master for heat-sensitive stencil printing according to any one of claims 1 to 5, wherein the reinforcing resin contains at least one of an electron beam curable resin and an ultraviolet curable resin.   The master for thermal stencil printing according to any one of claims 1 to 6, wherein the reinforcing resin is provided by either drying or curing after applying a reinforcing resin coating solution containing the reinforcing resin. Reinforcing resin coating solution having a nonvolatile coating amount of 2.0~40g / m ² at which claims 1 to 7 or a heat-sensitive stencil master according, including reinforced resin. The master for heat-sensitive stencil printing according to claim 8, wherein the coating amount of the nonvolatile component is 13 to 40 g / m ² .   The master for heat-sensitive stencil printing according to any one of claims 1 to 9, wherein the width of the reinforcing resin is 5 to 15 mm.   The heat-sensitive stencil master according to any one of claims 1 to 10, wherein the bending rigidity of the reinforcing resin is 20 to 200 mN.   Production of a master for thermosensitive stencil printing, comprising a porous resin film forming step of forming a porous resin film by applying a coating liquid for forming a porous resin film on a thermoplastic resin film and drying it. Method.

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