JP2002144751A - Master for stencil process printing, master making method and device, stencil process printing device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a non-conforming state such as printing irregularities due to the presence of a porous support for a master and enable a printing process to be performed with the help of the master showing excellent conveyance performance and high print quality. SOLUTION: The master 2 wrapped in the form of a roll is formed of only a porous resin film and a solvent 22 is applied to a part corresponding to a non-image part by a solvent application means 3 and thereby an ink non- passable part is formed to make the master. The site melted by applying the solvent 22 is dried/hardened by a drying means 4. The master 2 through with a making process is wrapped around the outer circumferential surface of a printing drum 8 and printing is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil printing master having ink passage holes, a method of making the stencil printing master, a stencil printing master making apparatus, and a stencil printing apparatus using the stencil printing master. And a stencil printing method using the stencil master.

[0002]

2. Description of the Related Art In a stencil printing machine, a printing drum (plate cylinder) is used.
A stencil master (hereinafter, also simply referred to as a master) perforated by a stencil making machine is wound around the outer peripheral surface of the stencil, ink is supplied from the inside of the printing drum, and the printing paper is pressed by a pressing member such as a press roller. Printing is performed by pressing against the outer peripheral surface. The printing drum has a porous support cylinder and a mesh screen layer which is a mesh of resin or metal fibers, and a master is wound on the mesh screen layer. When the printing paper is pressed against the printing drum by a pressing member such as a press roller,
The ink supplied to the inner peripheral surface of the printing drum oozes out from the opening of the printing drum and the perforated portion of the master, and is transferred to the printing paper.

[0003] A master used in a stencil printing machine is such that a porous thin paper or the like as an ink-permeable support (hereinafter, also simply referred to as a support) is attached to a thermoplastic resin film (hereinafter, also simply referred to as a film). Further, the film has a structure in which a stick preventing layer for preventing sticking with the thermal head is provided on the film surface. Actually, a film is attached to a mixture of hemp fiber or hemp fiber and synthetic fiber or wood fiber as a porous tissue paper, and,
Heat-sensitive stencil masters having a stick prevention layer on the film surface are widely used.

[0004] However, the above-mentioned heat-sensitive stencil master has the following problems. The adhesive accumulates like a bird's web in the area where the film and the overlapped part of the fiber are in contact, making it difficult for the thermal head to pierce that part. The fibers themselves impede the passage of ink, causing print unevenness. Fibers are expensive and inevitably the masters are also expensive. A process of bonding the film and the support is necessary,
The cost is high. Also, each material cost.

Japanese Patent Application Laid-Open No. Hei 10-24667 discloses a thermosensitive stencil in which a porous resin film as a support is coated and dried on one surface of a thermoplastic resin film in order to improve image quality. A printing master has been proposed. According to this master, the above-mentioned problems (1) to (4) are solved, but a coating and drying process is required, so that a problem equivalent to the above problem remains. In addition, when the master is wound around the printing drum, the ink is filled in the support corresponding to the opening of the printing drum, but the ink is discarded together with the support when the master is discharged. In the case of a printed matter of about 10%, ink capable of printing several tens of sheets is discarded for each plate discharge, and there is a problem that the consumption of ink increases.

Japanese Patent Application Laid-Open No. 54-33117 proposes a master for heat-sensitive stencil printing which consists essentially of a thermoplastic resin film without using a support. According to this master, since there is no support, all of the above-mentioned problems caused by the support are solved, and the problem of increased ink consumption is also solved.

[0007]

However, in the case of a master for heat-sensitive stencil printing which is substantially composed of only a thermoplastic resin film, a new problem has arisen. That is, a film having a high heat shrinkage ratio and a film thickness of 3 μm or less has good perforation by a thermal head and excellent print quality, but has a problem that it is stiff and difficult to convey. If a thick film is used to improve transportability, the perforation by the thermal head will decrease,
Printing unevenness occurs.

Therefore, the present invention can solve all of the above-mentioned problems caused by the support, and is excellent in transportability and print quality, a stencil printing master, a master making method, a master making apparatus, and a master making apparatus. And a stencil printing method using the master.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention focuses on a porous resin film which has conventionally been used as a support for a thermoplastic resin film, and improves ink permeability and stiffness. The porous resin film itself having the same is used as a master. At the stage of manufacture, the porous resin film already has a hole corresponding to a perforated portion as an ink passage hole formed based on image information with a conventional thermal head, and in the present invention, many holes already existing are formed. Of these, setting a portion corresponding to a non-image portion (a non-image portion in an image area) as an ink non-passing portion corresponds to a conventional plate making operation. Specifically, the invention according to claim 1 employs a configuration in which a stencil printing master made based on image information is formed only of a porous resin film.

According to a second aspect of the present invention, in the stencil printing master according to the first aspect, the porous resin film has a structure having a large number of voids inside and on the surface of the film. I am taking it.

According to a third aspect of the present invention, in the stencil printing master according to the second aspect, the gap is continuously present in a thickness direction of the film.

According to the fourth aspect of the present invention, the first to third aspects are provided.
In the stencil printing master described in any one of the above, the thickness of the porous resin film is not less than 5 μm and not more than 50 μm.

According to the fifth aspect of the present invention, the first to third aspects are provided.
In the stencil printing master according to any one of the above, the density of the porous resin film is 0.1 g / cm ³ or more and 0.7 g
/ Cm ³ or less.

According to the sixth aspect of the present invention, the first to third aspects are provided.
In the stencil printing master described in any one of the above, an average pore diameter of the porous resin film is 5 μm or more and 30 μm or less.

According to the seventh aspect of the present invention, a stencil master made of only a porous resin film is subjected to plate making while processing so that ink cannot pass through a portion corresponding to a non-image portion based on the image information. We are taking steps.

According to the invention described in claim 8, in the plate making method described in claim 7, a procedure is adopted in which the treatment for preventing the passage of the ink is to apply a solvent.

According to a ninth aspect of the present invention, in the plate making method of the eighth aspect, a procedure is adopted in which the solvent is applied and then dried by force.

According to the tenth aspect of the present invention, in the plate making method according to the eighth or ninth aspect, a procedure is adopted in which the solvent dissolves the porous resin film.

In the eleventh aspect of the present invention, in the plate making method of the eighth or ninth aspect, a procedure is adopted in which the solvent swells the porous resin film.

According to the twelfth aspect of the present invention, in the plate making method of the seventh aspect, the treatment for preventing the ink from passing is to heat and melt the ink by a heating means.
The procedure is adopted.

According to a thirteenth aspect of the present invention, in the plate making method according to the twelfth aspect, a procedure is adopted in which heating and melting are performed, followed by forcible cooling.

According to a fourteenth aspect of the present invention, in the plate making method of any one of the seventh to thirteenth aspects, the peeled surface of the porous resin film in the production thereof is used as a plate making surface.
The procedure is adopted.

According to the present invention, an ink non-passing portion forming means for processing a portion corresponding to a non-image portion based on image information of the stencil printing master comprising only a porous resin film so that ink cannot pass therethrough. Is adopted.

According to a sixteenth aspect of the present invention, in the plate making apparatus of the fifteenth aspect, the ink non-passing portion forming means is a solvent applying means for applying a solvent to a portion corresponding to a non-image portion. I am taking it.

According to a seventeenth aspect of the present invention, in the plate making apparatus of the sixteenth aspect, a configuration is adopted in which a drying unit is provided downstream of the solvent coating unit in the master transport direction.

[0026] In the invention according to claim 18, in the plate making apparatus according to claim 16 or 17, the solvent is used for dissolving the porous resin film.

According to a nineteenth aspect of the present invention, in the plate making apparatus of the sixteenth or seventeenth aspect, the solvent is used to swell the porous resin film.

According to a twentieth aspect of the present invention, in the plate making apparatus of the fifteenth aspect, the ink non-passing portion forming means is a heating means for heating and melting a portion corresponding to the non-image portion. I have.

According to a twenty-first aspect of the present invention, in the plate making apparatus of the twentieth aspect, a cooling means is provided downstream of the heating means in the master transport direction.

According to a twenty-second aspect of the present invention, in the plate making apparatus according to any one of the fifteenth to twenty-first aspects, a configuration is adopted in which a peeling surface of the porous resin film in the production thereof is a plate making surface. ing.

In the stencil printing apparatus according to the twenty-third aspect, the stencil master is made by a stencil master based on the image information, and the stencil master is wound around the outer peripheral surface of a printing drum for printing. The plate making device is
This is one of claims 15 to 22.

In the invention according to claim 24, a stencil printing master consisting only of a porous resin film is subjected to plate making while processing so as to prevent ink from passing through a portion corresponding to a non-image portion based on the image information. The printing stencil master is wound around the outer peripheral surface of the printing drum, and printing is performed by supplying ink from the inside of the printing drum.

According to the twenty-fifth aspect of the present invention, the stencil master made of only the porous resin film is subjected to plate making while processing a portion corresponding to a non-image portion based on the image information so as to prevent ink from passing therethrough. The stencil printing master is wound around the outer peripheral surface of the printing drum so that the stencil surface is on the inside, and printing is performed by supplying ink from the inside of the printing drum.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, an outline of the overall configuration of a stencil printing apparatus according to the present embodiment will be described with reference to FIG. The stencil printing apparatus 1 mainly includes a stencil making device 110 for making the master 2, a printing unit 120, a stencil discharging unit 130, a pressing unit 170, and the like. The stencil making device 110 is disposed above a substantially central portion of the stencil printing device main body, and includes a master support member 20 that rotatably supports the master 2 wound in a roll shape, and an ink non-passing portion forming unit. It has a solvent application unit 3, a drying unit 4, a cutting unit 5 for cutting the master 2 at a position of a predetermined length, a guide plate 6 for guiding the transfer of the master 2, a transfer roller 7 for transferring the master 2, and the like. (Claims 15, 16, 17, 23).

The solvent application means 3 selectively applies a solvent for dissolving the master 2 on one surface of the master 2 selectively, that is, on a portion corresponding to a non-image portion, based on the input image information. Although not shown, it has a tank filled with a solvent and a discharge head including a heating element, a piezoelectric element, and the like. The drying unit 4 is located downstream of the solvent application unit 3 in the master transport direction, and has a blower fan.
It has a function of accelerating the drying and solidification of the melting portion of the master 2 (claims 17 and 23). The drying unit 4 may be configured to blow warm air using a heating unit. The cutting means 5 is located downstream of the drying means 4 in the master transport direction,
It has an upper blade 5a and a lower blade 5b. The transport roller 7 transports the master 2 while holding the master 2 against the guide plate 6 so as to hold the leading end of the master 2 by a holding unit 14 described later.

The printing means 120 is disposed on the lower left side of the plate making apparatus 110 in the figure, and mainly comprises the printing drum 8 and the ink supply means 9 provided inside the printing drum 8. Although not shown, the printing drum 8 has a porous support cylinder and a mesh screen layer which is a mesh of resin or metal fiber, and has an opening 8a formed on the outer peripheral surface thereof, and ink supply is performed. Support shaft 1 that also serves as a pipe
It is provided rotatable around 0. The support shaft 10 has a plurality of openings on its surface, and supplies ink to the ink supply means 9 through the openings. The ink supply means 9 includes:
It has an ink roller 11, a doctor roller 12, and the like, and has a well-known configuration in which ink from a wedge-shaped ink reservoir 13 supplied from the support shaft 10 is supplied to the inner peripheral surface of the printing drum 8.

On the outer peripheral surface of the printing drum 8, the holding means 1
4 are provided. The holding means 14 has a stage 15 formed by a plane extending along the generatrix of the printing drum 8 and a clamper 16 for holding the leading end of the master 2. The clamper 16 is provided on a support shaft 16 a rotatably supported on the outer peripheral surface of the printing drum 8,
Opening and closing operation is performed under predetermined timing by opening and closing means (not shown). The plate discharging means 130 is disposed on the left side of the printing drum 8 and includes an upper plate discharging roller 17 and a lower plate discharging roller 18.
And a plate discharge box 19 for storing the used master 2. Upper plate discharging roller 17 and lower plate discharging roller 18
Is rotated by a driving unit (not shown), and the upper plate discharge roller 17 is provided so as to be able to freely contact and separate from the outer peripheral surface of the printing drum 8 by a contacting / separating unit (not shown). The stencil discharge box 19 is provided detachably with respect to the stencil printing apparatus main body.

The pressing means 170 provided below the printing drum 8 has a press roller 38, an arm shaft 39, a pair of press roller arms 40 and the like. The arm shaft 39 is rotatably supported by a casing side plate (not shown), and one end of the press roller arm pair 40 is fixed to the arm shaft 39. The shaft of the press roller 38 is rotatably supported by the other end of the press roller 38, and is urged toward the print drum 8 by a spring member (not shown). To come and go. The press roller 38 is held at a position separated from the printing drum 8 except when the paper is passed, by a locking means (not shown).

A registration roller pair 41 is provided below the plate discharging means 130. The printing paper 42 fed by a feeding means (not shown) is temporarily stopped by the pair of registration rollers 41 to correct skew and the like, and then conveyed to the printing pressure portion of the printing drum 8 at a predetermined timing. The press roller 38 contacts the print drum 8 in synchronization with this timing. In the vicinity of below both ends of the printing drum 8,
A peeling claw 43 for peeling the printing paper 42 from the outer peripheral surface of the printing drum 8 is provided. Each of the peeling claws 43 is rotated by driving means (not shown) so that the leading end thereof comes into contact with the outer peripheral surface of the printing drum 8. Let go. On the right side of the print drum 8, a paper discharge tray 46 for loading printed printing paper is provided, and the paper discharge tray 46 is fixed to the main body of the stencil printing apparatus.

As shown in FIG. 2, the master 2 in this embodiment is composed of only a porous resin film made of a thermoplastic resin (Claim 1), and has a resin portion 2a (solid black portion);
It is composed of a large number of voids 2b (white portions) formed inside and on the surface of the film (claim 2). From the viewpoint of ink permeability, a structure in which the voids 2b are continuous in the thickness direction in the film is desirable (claim 3).

The average pore diameter of the porous resin film 2 (hereinafter also referred to as master 2), that is, the average diameter of the voids 2b is 2 μm.
It is at least 50 μm and preferably at least 5 μm and at most 30 μm. If the average pore size is less than 2 μm, the ink permeability is poor. Therefore, if a low-viscosity ink is used in order to obtain a sufficient amount of ink to pass through, the image may bleed or the ink may seep out from the side of the printing drum 8 or the rear end of the wound master 2 during printing. A phenomenon occurs.
In addition, the porosity in the porous resin film 2 is often low, and the passage of the ink is easily hindered.

On the other hand, when the average pore diameter exceeds 50 μm, the effect of suppressing the transfer amount of ink by the porous resin film 2 is reduced, and the ink between the printing drum 8 and the printing drum 8 is excessively extruded at the time of printing, so that the back stain is caused. Troubles such as bleeding and bleeding occur. That is, if the average pore size is too small or too large, good print quality cannot be obtained. In particular, the voids 2 in the porous resin film 2
When the average pore size of b is 20 μm or less, the thicker the porous resin film 2 is, the more difficult it is for ink to pass through. Therefore, the amount of ink transferred to printing paper can be controlled by the thickness of the porous resin film 2.

If the thickness of the porous resin film 2 is not uniform, printing unevenness may occur. Therefore, it is desirable that the thickness be uniform. The thickness of the porous resin film 2 in the present embodiment is 2 μm or more and 100 μm or less, preferably 5 μm or more and 50 μm or less (claim 4). If the thickness is less than 5 μm, the printing durability may be reduced and the image may be stretched. The density of the porous resin film 2 is usually 0.1.
It is not less than 01 g / cm ^{3 and not} more than 1 g / cm ³ , preferably not less than 0.1 g / cm ^{3 and not} more than 0.7 g / cm ³ (claim 5). When the density is less than 0.01 g / cm ³ , the strength of the film is insufficient, and the film itself is easily broken. The adhesion amount of the porous resin film 2 is 0.1 g / m ² or more and 35 g / m ²
Or less, preferably ^{0.5g / m 2 ~25g / m 2} , in particular, 1~11g / m ² is desirable. Adhesion amount of increase will degrade the image quality prevent passage of ink, it is difficult to suppress the ink transfer amount is 0.1 g / m ² or less, contrary to 35 g / m ²
Above, the passage of ink is hindered and the image quality is degraded.

The resin material constituting the porous resin film 2 includes polyvinyl acetate, polyvinyl butyral, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, styrene-acrylonitrile copolymer and the like. Vinyl resins, polyamides such as polybutylene and nylon, polyphenylene oxide, (meth) acrylate, polycarbonate, polyurethane, cellulose derivatives such as acetylcellulose, acetylbutylcellulose and acetylpropylcellulose. Each resin may be used as a mixture of two or more.

In order to adjust the formation, strength, pore size and the like of the porous resin film 2, it is desirable to add an additive such as a filler to the porous resin film 2 as needed. Here, the filler is a concept including a pigment, a powder, and a fibrous substance. Among them, needle-like fillers are particularly preferable. Specific examples include magnesium silicate, sepiolite, potassium titanate, wollastonite, zonolite, mineral needle fillers such as gypsum fiber, non-oxide needle whiskers, oxide whiskers, and double oxide whiskers. Artificial mineral needle fillers such as mica, glass flakes, etc.
A plate-like filler such as talc may be used. Pigments are inorganic as well as organic pigments, or organic polymer particles such as polyvinyl acetate, polyvinyl chloride, polymethyl acrylate, and zinc oxide, titanium dioxide, calcium carbonate,
It is silica. Matsumoto Microsphere, a microcapsule manufactured by Matsumoto Yushi Seiyaku Co., Ltd., can also be used effectively.

The addition amount of these additives is preferably 5% to 200% with respect to the resin. If it is less than 5%, the bending stiffness due to the addition of the additive does not increase. Conversely, if it is 200% or more, the bending stiffness becomes too high. An antistatic agent, an anti-stick agent, a surfactant, a preservative, an antifoaming agent, and the like can be used in the porous resin film 2 as long as the function of forming an ink non-passing portion described later is not impaired.

Next, a method of forming the master 2 (porous resin film) in the present embodiment will be described. (First forming method) A coating liquid obtained by dissolving and / or dispersing a resin in a mixed solvent of a good solvent and a poor solvent is applied to a non-adhesive support, and a porous film is formed in a drying process. Form. At this time, a combination of a good solvent and a relatively easy-to-evaporate at a lower temperature than a poor solvent is required. When one good solvent and one poor solvent are used, respectively, the boiling point of the good solvent must be relatively lower than the boiling point of the poor solvent. The selection of a good solvent and a poor solvent is arbitrary, but generally, when the difference in boiling point is 15 to 40 ° C., a porous resin film having desired characteristics is easily formed.
If the boiling point difference is less than 10 ° C., the evaporation time difference between the two solvents is small, and the formed film is unlikely to have a porous structure. If the boiling point of the poor solvent is too high, drying takes a long time and the productivity is poor, so the boiling point of the poor solvent is desirably 150 ° C. or lower.

The resin concentration in the coating solution varies depending on the material used, but is 5 to 30%. If it is less than 5%, the opening diameter becomes too large, and the thickness of the porous resin film tends to be uneven. Conversely, if it exceeds 30%, it is difficult to form a porous resin film, or even if it is formed, the pore size becomes small and it is difficult to obtain desired characteristics. The average pore size of the porous resin film is affected by the poor solvent in the atmosphere. In general, the higher the ratio to the good solvent, the larger the amount of coagulation and the larger the average pore size. Since the addition ratio of the poor solvent differs depending on the resin and the solvent, it is necessary to appropriately determine the ratio by experiment. Generally, the pore size of the porous resin film increases as the amount of the poor solvent added increases. If the amount of the poor solvent is too large, the resin is precipitated and the coating liquid becomes unstable.

(Second Forming Method) JP-A-11-2358
No. 85, a fluid mainly composed of a W / O emulsion is applied to a non-adhesive support and dried. In this method, mainly water portions become holes through which the ink passes after drying, and the resin (which may contain additives such as fillers and emulsifiers) in the solvent becomes a structure. Also in this method, the formation of the porous membrane, the strength, the size of the pore size,
In order to control the stiffness and the like, an additive such as the filler can be added to the porous film as needed. Among them, needle-like, plate-like, or fibrous fillers are particularly preferable. To form a W / O emulsion, HLB (Hydrophiric Lyophiric Balance) having a relatively strong lipophilicity is 4%.
Are effective, but the HLB is 8 in the aqueous layer.
More stable and uniform W /
An O-type emulsion is obtained. The use of a polymeric surfactant is one of the methods for obtaining a more stable and uniform emulsion. Addition of a thickener such as polyvinyl alcohol or polyacrylic acid to an aqueous system is effective for stabilizing the emulsion. The method of forming the porous resin film is not limited to the above two methods.

The coating method of the coating liquid for forming a porous resin film may be a coating method generally used conventionally such as a blade, a transfer roll, a wire bar, a reverse roll, a gravure, a die, etc., and is particularly limited. Not something. The porous resin film is applied to a non-adhesive support,
It is obtained by being dried and then peeled off from the non-adhesive support. Since the peeled surface at this time has good smoothness, it is preferable that the peeled surface be a plate-making surface so that uniform plate-making is performed.

The printing operation of the stencil printing apparatus 1 based on the above configuration will be described below. The original 47 (see FIG. 3) is placed on an original reading unit (not shown) of the stencil
An operation is performed to set the image area 48 of the original 47 to be printed by a print area designating device such as a digitizer, and a start signal is transmitted by pressing a start key on an operation panel (not shown). The document 47 is transported by a document transport device (not shown), and its optical information is converted into an electric signal by a CCD (Charge Coupled Device) (not shown) or the like.
The digital signal is written to a memory device (not shown) via the converter. At the same time, a driving unit (not shown) of the printing drum 8 operates, the printing drum 8 rotates clockwise, and the upper plate discharging roller 17 of the plate discharging unit 130 is rocked by a rocking unit (not shown). Abuts the outer peripheral surface of. The used master 2 is peeled off from the outer peripheral surface of the printing drum 8 by the upper plate discharging roller 17,
The separated master 2 is accommodated in the plate discharge box 19.

Next, the driving means for rotating the printing drum 8 is operated, and the printing drum 8 is rotated and stopped until the holding means 14 reaches a predetermined plate feeding position. When the holding unit 14 reaches a predetermined plate feeding position, an opening / closing unit (not shown) operates to rotate the clamper 16 in a direction away from the stage unit 15. At about the same time, a stepping motor (not shown) operates, and the transport roller 7 starts rotating, and the master 2
Is transported. The master 2 is wound in a roll shape such that the peeled surface in the manufacture thereof becomes the surface. The ejection head of the solvent application unit 3 is driven while the digital signal is read from the memory device, and plate making on the master 2 in the plate making device 110 is started. The solvent 22 is applied from the discharge head to the non-image portion (the conventional non-perforated portion in the image region) in the portion 49 corresponding to the image region 48 of the original 47 shown in FIG. Items 7, 8, 18, 23). In FIG. 3, reference numeral 50 (hatched display) indicates an area other than the image area.

The solvent 22 contains the resin portion 2 a of the porous resin film 2.
Is selected as a good solvent. As shown in FIG. 4, the resin portion 2a corresponding to the non-image portion is dissolved and deformed by the solvent 22, and the gap 2b is closed (claim 10).
By blowing air by the drying means 4 and drying, an ink non-passing portion 2c is formed on the master 2 (claim 9). In FIG. 4, reference numeral 49a denotes an ink passage portion (conventional perforated portion). Since the master 2 is wound so that the peeled surface in the manufacture thereof becomes the front surface (upper surface), plate making is performed on the peeled surface.
2). Since the image is obtained by pressing the printing paper 42 against the master 2 to transfer the ink, the ink non-passing portion 2 c on the master 2 is a mirror image of the original 47. Even if the solvent is not dissolved, a solvent may be used that swells the resin portion 2a to close the gap 2b and forms an ink non-passing portion (claims 11, 19, and 23). Further, as shown in FIG. 5, by adjusting (increasing) the amount of the solvent discharged from the discharge head to increase the solubility and decreasing the height of the ink non-passing portion 2c, the ink non-passing portion 2c is reduced.
The amount of ink filled in the portion corresponding to c can be reduced, and the amount of ink discarded at the time of plate discharging can be further reduced.

In the present embodiment, the solvent 22 is applied from the discharge head. However, instead of the solvent 22, a resin solution in which an arbitrary resin is dissolved by a solvent or a configuration in which the resin is heated and melted and applied. Is also good. At this time, it is particularly preferable that the selected resin is the same as the raw material of the porous resin film 2 from the viewpoint of compatibility with the porous resin film 2. However, the method of applying the solvent 22 as in the present embodiment is preferable from the viewpoint of cost and simplicity of the mechanism.

The master 2 having undergone plate making is conveyed by the conveying roller 7 while its leading end is guided by the guide plate 6, and the leading end eventually reaches the stage 15 of the holding means 14. A control device (not shown) that indicates that the leading end of the master 2 has reached the holding position of the holding means 14 (for example, a stencil printing device 1)
(The main controller) outputs an operation command to the opening / closing means (not shown). As a result, the opening / closing means is operated to close the clamper 16, and the leading end of the master 2 is clamped between the stage 15 and the clamper 16. When the leading end of the master 2 is held by the holding means 14, the driving means for driving the printing drum 8 operates, and the printing drum 8 is driven.
Is rotated counterclockwise at substantially the same speed as the master transport speed of the transport roller 7. Thereby, the printing drum 8
The master 2 starts to be wound on the outer peripheral surface of. When the master 2 is wound for a predetermined length, the cutting means 5 cuts the master 2 and the winding of the master 2 around the printing drum 8 is completed.

After the completion of plate feeding, printing is performed. The printing paper 42 held between the registration roller pair 41 and waiting is
The printing drum 8 and the press roller 38 are timed.
To the contact portion (transfer portion). When the printing paper 42 is pressed against the outer peripheral surface of the printing drum 8 (strictly, the outer surface of the master 2) by the press roller 38, the ink supplied by the ink supply means 9 forms the ink non-passing portion 2 c of the master 2. Is transferred through a part that is not
An image is formed on the surface of No. 2 (claim 24). The printing paper 42 on which the image has been formed is peeled off from the outer peripheral surface of the printing drum 8 by the peeling claw 43, discharged to a paper discharge tray 46, and stacked.

Next, another embodiment will be described with reference to FIG. The same parts as those in the above-described embodiment are denoted by the same reference numerals, and the description of the already-described configuration and function will be omitted unless otherwise required. Except for the plate making device, the embodiment is the same as the above embodiment, and the illustration and description thereof are omitted. The plate making apparatus 180 according to the present embodiment includes a thermal head 59 as a heating unit that selectively heats and melts the master 2 based on image information, instead of the solvent coating unit 3 according to the above embodiment.
And a platen roller 60 that conveys the master 2 while pressing the master 2 against the thermal head 59 (claims 12, 20, and 23). In the present embodiment, the drying unit 4 serves as a cooling unit. The thermal head 59 is provided so as to be able to freely contact and separate from the platen roller 60 by a contacting / separating means (not shown). The platen roller 60 is rotatably supported by the stencil printing apparatus main body, and is driven to rotate by a stepping motor (not shown).

The thermal head 59 has a structure as shown in FIG. (C) is a view of the minute heating portion of the thermal head 59 as viewed from above, and (b) is a cross-sectional view thereof. Reference numeral 1A indicates a heating element layer made of a high electric resistance material, reference numeral 1B indicates a lead electrode, and reference numeral 1C indicates a protective film. In (b), the lead electrode 1B is omitted. The heating element layer 1A is formed on the substrate E.
When a voltage is applied between the lead electrodes 1B, the lead electrodes 1B
An electric current flows through the heating element layer 1A between B and the heating element layer 1A in the energized portion generates heat by Joule heat. Such minute heat generating portions are closely arranged at a constant pitch in the main scanning direction, and the resin portion 2a corresponding to the non-image portion is melted and deformed while the master 2 is being conveyed in the sub scanning direction, The gap 2b is closed. By cooling by blowing air by the cooling means 4, solidified ink non-passing portions 2c are formed on the master 2 (claims 13, 21 and 23).

When melting energy is supplied to the heat generating portion of the thermal head 59 in the form of electric energy, the energy is converted into heat energy by the heat generating layer 1A, and the porous resin film in contact with the protective film 1C is formed. The temperature of 2 rises. The temperature distribution at this time is as shown in FIG. Symbol D is a threshold temperature at which the porous resin film 2 is melted. By applying a temperature equal to or higher than the threshold temperature,
A resin film in which the gap 2b is continuously closed in the main scanning direction can be formed. Similarly, in the sub-scanning direction, the size of the heating element layer 1A and the heating element layer 1A in the sub-scanning direction are set so that a temperature equal to or higher than the threshold temperature is continuously applied to the master 2.
By adjusting the power supply time to the resin, a resin film in which the gap 2b is continuously closed can be formed.

The platen roller 60 starts rotating and conveys the master 2, and plate making on the master 2 in the plate making device 180 is started. As shown in FIG. 3, the master 2 is heated and melted by the thermal head 59 while leaving a portion 49 corresponding to the image area 48. The melted resin portion 2a is blown and cooled by the cooling means 4 to form a solidified ink non-passing portion 2c on the master 2. An antistatic agent, an anti-stick agent, a surfactant, a preservative, an antifoaming agent, and the like can be used in combination with the porous resin film 2 as long as the ink non-passing portion forming function is not impaired.

Next, another embodiment will be described with reference to FIG. The same parts as those in the above embodiment are denoted by the same reference numerals, and the description of the already-described configuration and function will be omitted unless necessary. The present embodiment is characterized in that the stencil making surface of the master 2 is wound in contact with the outer peripheral surface of the printing drum 8, and the rotation direction of the printing drum 8 and the clamper 16.
The configuration is the same as that of the first embodiment, except for the position and the like. The master 2 on which the plate has been made is sent to the clamper 16 in an open state by the pair of transport rollers 65, and is wound around the leading end portion thereof. As shown in FIG. 9, the master 2 is wound so that its plate making surface is in contact with the outer peripheral surface of the printing drum 8 (claim 25). For this reason, the ink is not filled in the ink non-passing portion 2c which is the non-image portion, and the ink discarded at the time of plate discharging can be saved. The same can be implemented in a configuration using the plate making apparatus 180 shown in FIG.

In each of the above embodiments, the master 2 usually wound around the outer peripheral surface of the printing drum 8 has a so-called effective image area where ink adheres and an area where ink does not adhere. Naturally, the formation process of the ink non-passing portion 2c is not performed in the area where the ink does not adhere.

In each of the above embodiments, the master 2 composed of only the porous resin film is used, but a porous fiber film composed of fibers may be laminated on the porous resin film for reinforcement. Examples of the porous fiber membrane include glass, sepiolite, mineral fibers such as various metals, animal fibers such as wool and silk, natural fibers such as cotton, manila hemp, mulberry, mitsumata, pulp, regenerated fibers such as souff and rayon, polyester, Examples include synthetic fibers such as polyvinyl alcohol and acrylic, semi-synthetic fibers such as carbon fiber, and thin paper such as inorganic fibers having a whisker structure. In this case, the thickness of the fibrous material is
The diameter is 20 μm or less, preferably 1 to 10 μm. If the diameter is smaller than 1 μm, the tensile strength is weak, and
If it is larger than m, ink passage is hindered and so-called white spots due to fibers appear on the image. The length of the fibrous material is preferably about 0.1 to 10 mm, more preferably about 1 to 6 mm. If it is shorter than 0.1 mm, the tensile strength becomes weak, and if it is longer than 10 mm, it is difficult to perform uniform dispersion. Instead of the porous fiber membrane, a mesh screen made of nylon fiber, metal fiber, or the like, or a porous membrane made of a porous sheet or film having a large number of through holes may be used. Further, a pattern may be printed by a printing method such as gravure, offset, or flexo, or a porous film may be formed by nozzle coating or the like.

[0064]

According to the first aspect of the present invention, since the stencil master is formed only of the porous resin film, it is possible to obtain a stencil master excellent in transportability and printing quality and at low cost. .

According to the second aspect of the invention, since the porous resin film has a structure having a large number of voids inside and on the surface of the film, good ink permeability can be obtained.

According to the third aspect of the present invention, since the voids are continuously formed in the thickness direction of the film, good ink permeability can be obtained.

According to the fourth aspect of the present invention, since the thickness of the porous resin film is not less than 5 μm and not more than 50 μm, good printing durability can be obtained and occurrence of image elongation can be suppressed. can do.

According to the fifth aspect of the present invention, since the density of the porous resin film is 0.1 g / cm ³ or more and 0.7 g / cm ³ or less, good film strength can be obtained. it can.

According to the sixth aspect of the present invention, since the average pore diameter of the porous resin film is 5 μm or more and 30 μm or less, it is possible to obtain a sufficient ink passage amount without causing image bleeding. it can.

According to the seventh aspect of the present invention, a stencil master made only of a porous resin film is subjected to plate making while processing a portion corresponding to a non-image portion based on the image information so that ink cannot pass through. As a result, it is possible to solve the problems caused by the conventional master support, and to improve the transportability and print quality.

According to the eighth, tenth, or eleventh aspect of the present invention, the solvent is applied so as to prevent the ink from passing, so that the problem caused by the conventional master support can be solved. Transportability and print quality can be improved.

According to the ninth aspect of the present invention, since the solvent is forcibly dried after being applied, the chemical reaction site can be efficiently dried and solidified, and the ink non-passing portion can be formed. It can be performed with high accuracy.

According to the twelfth aspect of the invention, the ink is heated and melted by the heating means so as to prevent the ink from passing therethrough, so that the problem caused by the conventional support of the master can be solved and the transportability can be improved. And print quality can be improved.

According to the thirteenth aspect of the present invention, since the molten portion is forcibly cooled after being heated and melted, the molten portion can be efficiently solidified, and the ink non-passing portion can be formed with high precision. be able to.

According to the fourteenth aspect of the present invention, since the release surface in the production of the porous resin film is used as a plate making surface, the release surface has good smoothness. It can be carried out.

According to the invention of claim 15 or 23,
Since the stencil printing master consisting only of the porous resin film has an ink non-passing portion forming means for processing so as to prevent ink from passing through a portion corresponding to a non-image portion based on image information, the conventional configuration is adopted. In addition to solving the problems caused by the support of the master, the transportability and the print quality can be improved.

According to the invention of claim 16, 18, 19 or 23, the ink non-passing portion forming means is a solvent applying means for applying a solvent to a portion corresponding to a non-image portion. In addition to solving the problems caused by the support of the master, the transportability and the print quality can be improved.

According to the invention of claim 17 or 23,
Since the drying means is provided downstream of the solvent application means in the master transport direction, the chemical reaction site can be efficiently dried and solidified, and the ink non-passing portion can be formed with high precision. .

According to the invention of claim 20 or 23,
Since the ink non-passing portion forming means is a heating means for heating and melting the portion corresponding to the non-image portion, it is possible to solve the problems caused by the conventional support of the master and to improve the transportability and the printing quality. Can be done.

According to the invention of claim 21 or 23,
Since the cooling means is provided downstream of the heating means in the master transport direction, the melted portion can be efficiently cooled and solidified, and the ink non-passing portion can be formed with high accuracy.

According to the twenty-second aspect of the present invention, since the release surface in the production of the porous resin film is a plate making surface, the release surface has good smoothness. It can be carried out.

According to the twenty-fourth aspect of the present invention, a stencil master made of only a porous resin film is subjected to plate making while processing a portion corresponding to a non-image portion based on the image information so that ink cannot pass through. Since the stencil master for stencil printing is wound around the outer peripheral surface of the printing drum and printing is performed by supplying ink from the inside of the printing drum, problems caused by the conventional master support can be solved. , Transportability and print quality can be improved.

According to the twenty-fifth aspect of the present invention, a stencil printing master made of only a porous resin film is subjected to plate making while processing so that ink cannot pass through a portion corresponding to a non-image portion based on the image information. The stencil master for stencil printing is wound around the outer peripheral surface of the printing drum so that the stencil surface is on the inside, and printing is performed by supplying ink from the inside of the printing drum. Ink can be saved.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a stencil printing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a master.

FIG. 3 is a perspective view showing a correspondence between a document and an image portion of a master.

FIG. 4 is a cross-sectional view taken along line AA of FIG.

FIG. 5 is a cross-sectional view taken along line AA of FIG. 3 in another embodiment.

FIG. 6 is a schematic front view of a plate making apparatus according to another embodiment.

7A and 7B are views showing the thermal head in the embodiment shown in FIG. 6, wherein FIG. 7A is a graph showing thermal characteristics, FIG. 7B is a cross-sectional view of a heat generating portion, and FIG. 7C is a plan view of the heat generating portion. .

FIG. 8 is a schematic front view of a stencil printing apparatus according to another embodiment.

FIG. 9 is a schematic sectional view of a master in the embodiment shown in FIG.

[Explanation of symbols]

 2 Porous resin film 3 Solvent coating means as ink non-passing portion forming means 4 Drying or cooling means 59 Thermal head as heating means 110, 180 Plate making device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B41M 1/12 B41M 1/12 F term (Reference) 2H084 AA13 AA25 AA38 AE05 AE06 BB04 BB13 CC09 2H113 AA01 AA02 AA05 BA09 BB02 BB22 DA04 DA52 DA53 DA57 DA68 EA05 EA07 EA08 FA10 FA29 FA32 2H114 AB23 BA00 BA06 BA10 DA04 DA51 DA52 DA56 DA76 DA78 EA01 EA08 FA06 GA34 GA38

Claims (25)

[Claims] 1. A stencil printing master that is made based on image information, characterized in that the stencil printing master comprises only a porous resin film. 2. The stencil printing master according to claim 1, wherein the porous resin film has a structure having a large number of voids inside and on the surface of the film. 3. A stencil printing master according to claim 2, wherein said voids are continuously present in the thickness direction of the film. 4. The stencil printing master according to claim 1, wherein said porous resin film has a thickness of 5 μm or more and 50 μm or less. 5. The stencil printing master according to claim 1, wherein the density of the porous resin film is 0.1 g / cm ³ or more and 0.1 g / cm ³ or more.
A stencil master having a weight of 7 g / cm ³ or less. 6. The stencil printing master according to claim 1, wherein the porous resin film has an average pore diameter of 5 μm or more and 30 μm or less. 7. A stencil printing method, wherein a stencil printing master comprising only a porous resin film is subjected to stencil processing while processing a portion corresponding to a non-image portion based on the image information so as to prevent ink from passing therethrough. 8. The plate making method according to claim 7, wherein the treatment for preventing the passage of the ink is to apply a solvent. 9. The plate making method according to claim 8, wherein the solvent is forcibly dried after being applied. 10. The plate making method according to claim 8, wherein the solvent dissolves the porous resin film. 11. The plate making method according to claim 8, wherein the solvent swells the porous resin film. 12. The plate making method according to claim 7, wherein the step of treating the ink so as not to pass through is heating and melting by a heating means. 13. The plate making method according to claim 12, wherein the plate is forcibly cooled after being heated and melted. 14. The plate making method according to claim 7, wherein a peeled surface of the porous resin film in the production thereof is a plate making surface. 15. An ink non-passing portion forming means for processing a portion corresponding to a non-image portion based on image information of a stencil printing master comprising only a porous resin film so as to prevent ink from passing therethrough. A plate making apparatus characterized by the above-mentioned. 16. A plate making apparatus according to claim 15, wherein said ink non-passing portion forming means is a solvent applying means for applying a solvent to a portion corresponding to a non-image portion. 17. The plate making apparatus according to claim 16, further comprising a drying means downstream of the solvent applying means in the master transport direction. 18. The plate making apparatus according to claim 16, wherein said solvent dissolves said porous resin film. 19. The plate making apparatus according to claim 16, wherein the solvent swells the porous resin film. 20. A plate making apparatus according to claim 15, wherein said ink non-passing portion forming means is heating means for heating and melting a portion corresponding to a non-image portion. 21. A plate making apparatus according to claim 20, further comprising a cooling means downstream of said heating means in a master conveying direction. 22. A plate-making apparatus according to claim 15, wherein a release surface of said porous resin film in the production thereof is a plate-making surface. 23. A stencil printing machine for making a stencil printing master by a stencil printing machine based on image information and winding the stencil printing master around an outer peripheral surface of a printing drum for printing. A stencil printing machine characterized by one of items 15 to 22. 24. A stencil printing master comprising only a porous resin film is subjected to plate making while processing so as to prevent ink from passing through a portion corresponding to a non-image portion based on the image information. A stencil printing method, wherein the stencil printing method is performed by wrapping around an outer peripheral surface of a printing drum and supplying ink from inside the printing drum. 25. A stencil printing master made only of a porous resin film is subjected to plate making while processing so as to prevent ink from passing through a portion corresponding to a non-image portion based on the image information. A printing method, wherein the printing is performed by wrapping around the outer peripheral surface of a printing drum such that the plate making surface is inside, and supplying ink from inside the printing drum.