JP2002120470A - Master for stencil printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a winding shifting from developing at the handling of a master at its change and the lowering of the product quality of a master roll from developing even in the master roll, which is formed by winding the thin and highly smooth master. SOLUTION: In this master roll, some part 100a of a sheet member 100 is pinched between the tip part 64a (or the terminal part in a winding direction) of a master 64 wound in a roll and the outer peripheral surface of the roll. In addition, by covering the outer peripheral surface of the roll with the other end part (or a setting part 100b), the overlapping part of the sheet members 100 is formed. The overlapping parts are set with a seal or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a stencil printing master used in a stencil printing apparatus.

[0002]

2. Description of the Related Art In a stencil printing machine, a heat-sensitive stencil master (hereinafter referred to as a master as appropriate) formed by perforating and making a plate by a heating means such as a thermal head is wound around an outer peripheral surface of a perforated plate cylinder. The printing paper sent from the paper means is pressed against the outer peripheral surface of the plate cylinder by a press roller as a pressing member to perform printing. An ink supply means is provided inside the plate cylinder, and the ink supplied to the inside of the plate cylinder oozes through the opening of the plate cylinder and the perforated part of the master by the pressing force of the press roller, and the printing paper is printed. Is formed to form an ink image.

[0003] The master making of a master is performed by a plate making unit that is detachable from the main body of the apparatus. When the master runs out, the master making unit is removed from the main body of the apparatus, and after replacing the master, the master making unit is mounted on the main body of the apparatus. It has become. The master is wound in a roll shape, and is fed out of a roll state and transported during plate making. Transport and storage,
In the master exchange in the plate making unit, handling in a roll state is performed.

[0004] A master of this type is generally made by laminating a porous thin paper or the like as an ink-permeable support to a thermoplastic resin film with an adhesive, and forming a thermal head on the opposite surface of the thermoplastic resin film. It has a structure provided with a stick prevention layer for preventing the stick. Actually, a thermosensitive stencil master in which a thermoplastic resin film is bonded with an adhesive to hemp fiber or a mixture of hemp fiber and synthetic fiber or wood fiber as porous thin paper, and a stick prevention layer is provided. Is widely used.

[0005] Such a master has a bending stiffness of 50-1.
The stiffness is as high as 00 mN or more (the stiffness is strong) and the smoothness is as low as 5000 seconds. For this reason, the leading end of the master roll (the leading end in use; the end in the winding direction) is stopped by a stop member such as an adhesive tape or a seal.

In recent years, in order to improve the image quality and reduce the cost of the master, a thin and weak master has been used. JP-A-8-332785 proposes a thin master for higher image quality. This has a structure having a porous resin film formed by coating and drying on one surface of a thermoplastic resin film. The thickness of the porous resin film is 5 μm or more and 100 μm or less, preferably 6 μm or more and 50 μm or less.

[0007]

In the case of a conventional master having a high rigidity and a low smoothness, even if the above-described stopping method is used, the master roll is not properly wound when the master is replaced in the transport, storage, or plate-making unit. Did not occur. However, in a thin master as described in JP-A-8-332785, the thickness of the porous resin film is 5 μm.
If it is less than 2,000, it is difficult to obtain a sufficient waist, the smoothness is as high as 20,000 seconds or more, and the surface of the master is slippery.
For this reason, in the conventional method of stopping with a tape or a seal,
Several windings from the outside of the master roll were liable to be displaced, causing wrinkles and reducing the product value.
A similar problem occurs in a master made of only a thermoplastic resin film.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a roll-shaped stencil master capable of preventing winding deviation even when the stiffness is low and the smoothness is high.

In order to achieve the above object, according to the first aspect of the present invention, in a stencil printing master wound in a roll shape, a sheet member is sandwiched between a leading end portion of the master and an outer peripheral surface of the master. The other end of the sheet member extends in the winding direction of the master, goes around the outer peripheral surface of the master, and overlaps the sheet members beyond the leading end of the master, and the overlapping portion is stopped. , Is adopted. Here, the leading end of the master is a leading end when the roll-wound master is used, and means the end in the winding direction.

According to a second aspect of the present invention, in the stencil printing master according to the first aspect, the master has a structure in which a porous resin film is laminated on one surface of a thermoplastic resin film. The configuration is adopted.

According to a third aspect of the present invention, in the stencil printing master of the first aspect, the master is made of only a thermoplastic resin film.

According to the fourth 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 sandwiching length of the sheet member in the winding direction of the master is not more than the outer peripheral length of the master roll.

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 sandwiching length of the sheet member in the winding direction of the master is not less than 20 mm and not more than 150 mm.

According to the sixth aspect of the present invention, the first to fifth aspects are provided.
In the stencil printing master according to any one of the above, the width of the sheet member in the axial direction of the master roll is not less than 1/3 of the width of the master in the same direction and within a range equivalent to the width of the master. There is a configuration that there is.

[0015] In the invention according to claim 7, claims 1 to 6 are provided.
In the stencil printing master according to any one of the above, the thickness of the sheet member is 100 μm or less.

According to the invention described in claim 8, claims 1 to 7 are provided.
In the stencil printing master according to any one of the above, the surface of the sheet member is rougher than the surface of the master.

[0017]

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 configuration of a stencil printing apparatus 2 using a stencil printing master according to the present embodiment will be described with reference to FIG. The stencil printing apparatus 2 includes an image reading unit 4, a plate cylinder 6, a plate making unit 8 as a plate making unit, a paper feeding unit 10, and a press that is controlled to be moved toward and away from the plate cylinder 6 by a not-shown contacting / separating unit. A press roller 12 as a member, and a discharge claw 14 disposed near the discharge side of the plate cylinder 6
, A paper discharge conveying means 16, a paper discharge tray 18, a plate discharge means 20, and the like. Although not shown, the plate cylinder 6 has a base obtained by rolling a thin metal plate such as a stainless steel plate into a cylindrical shape, and a master 64 wound around the outer circumference of the plate cylinder 6 is held on the outer peripheral surface of the base. Clamper 22 is provided.

A large number of fine through-holes having a diameter of about 0.1 to 0.5 mm are formed in the substrate, so that the supplied ink can be oozed to the outer surface. The plate cylinder 6 is rotatably supported by a support shaft 24 also serving as an ink supply pipe, and an ink supply means 26 is provided inside. The ink supply means 26 has an ink roller 28 for supplying ink to the inner peripheral surface of the plate cylinder 6, a doctor roller 30, and the like. The ink supplied from the support shaft 24 to the ink reservoir 32 via a distribution pipe (not shown) is supplied to the ink roller 28 with its thickness regulated by the doctor roller 30, and the ink is supplied when the press roller 12 presses the printing paper P. The roller 28 comes into contact with the inner peripheral surface of the plate cylinder 6 to supply ink.

The paper feeding means 10 separates the loaded printing papers P one by one in cooperation with a separating member (not shown) in order from the top of the paper feeding table 34 on which the printing papers P are loaded. It has a feed roller 36 for feeding, a pair of registration rollers 38 for stopping the fed printing paper P once and correcting the oblique deviation or the like, and then feeding the printing paper P to the transfer portion of the plate cylinder 6 at a predetermined timing. . The paper discharging and conveying means 16 has a conveying belt 44 driven by a driving pulley 40 and a driven pulley 42, and a suction fan 46, and the printed printing paper P separated from the plate cylinder 6 by the paper discharging claws 14. The non-image surface (back surface) is transported by suction. The plate discharging means 20 includes separation rollers 48 and 50, plate discharging rollers 52 and 54, transport belts 56 and 58 stretched between these rollers, and a plate cylinder 6.
A master discharge box 60 in which a used master 64 separated from the outer peripheral surface of the master is stored, and a compression plate 62 for compressing the master 64 in the master discharge box 60.

Next, the printing operation of the stencil printing apparatus 2 will be briefly described. Based on the read image information of the original by the image reading means 4, the master making unit 8 performs perforating and making a master on the master 64, and the master made master 64 is clamped at its leading end by the clamper 22 of the plate cylinder 6. It is wound around the outer peripheral surface of the plate cylinder 6 as it rotates. After the master 64 is wound, the plate attaching operation is performed. The leading edge of the image on the plate cylinder 6 and the printing paper P
The printing paper P is sent by the pair of registration rollers 38 at a timing when the predetermined position in the transport direction coincides with the printing paper P, and the printing paper P is pressed against the printing drum 6 by the press roller 12 that moves toward the printing drum 6 at this timing. Is done. The ink supplied to the inner peripheral surface of the plate cylinder 6 by the ink roller 28 oozes out of the perforated portion of the master 64 through the fine through holes of the base, and is transferred to the printing paper P. Thus, an ink image is formed on the printing paper P. The printing paper P on which the ink image has been transferred is peeled off from the plate cylinder 6 by the paper ejection claws 14, and the paper ejection tray 18 (not shown) by the paper ejection conveyance means 16.
Conveyed toward. When printing of a predetermined number of sheets is completed, the used master 64 is separated from the plate cylinder 6 by the plate discharging means 20.

Next, the plate making unit 8 will be described with reference to FIG. The plate making unit 8 has a unit frame 66, and the unit frame 66 is detachably provided to the apparatus main body via a guide member 67. In the unit frame 66, a roll-shaped master 64, a master set roller 68 and a set plate 70, a master set sensor 72 as a master set detecting means for detecting a set state of the master, a thermal head 74,
A platen roller 76 that presses the master 64 against the thermal head 74 and conveys it, a pair of conveying rollers 78, a master cutting unit 80, a master tip sensor 82, and a pair of conveying rollers 8.
4, a guide 86 for guiding the leading end of the master 64 to the clamper 22 of the plate cylinder 6 at the time of plate feeding, a bending box 88 and the like. The master cutting means 80 is of a guillotine type and has a moving blade 80a and a fixed blade 80b. The flexible box 88 is provided with a guide plate 88a which is selectively set at a position where the master 64 is transported and a position where the master 64 is stored, and a suction fan 88b.

Each operation of the stencil printing machine 2 is controlled by the control means 90 shown in FIG. The control means 90 controls the CP
A microcomputer including U, ROM, RAM, I / O interface, etc.
2. A detection signal from the master tip sensor 82 and the like and setting information from the operation panel 92 are input. The control means 90
The thermal head 74, the platen motor 91, the operation panel 92 and the like are controlled based on these information.

As shown in FIG. 4, the master 64
5 is wound in a roll shape, and the starting end thereof is stopped by a weak adhesive force (a force enough to peel off by the conveying force of the master 64) to the core material 65. The outer peripheral surface of the master 64 wound in a roll shape is covered with a sheet member 100,
The sheet member 100 is stopped at three places by an adhesive seal 102 indicated by hatching. As a result, the master 64 is stopped so as not to vary.

As shown in FIG. 5 and FIG.
A part of 00 (indicated by hatching for easy distinction) is sandwiched between the front end portion 64a of the master 64 and the outer peripheral surface 64b of the roll-shaped master 64 wound before that. Nipping portion 100a of sheet member 100
Is less than or equal to the outer peripheral length of the master roll (the outer peripheral length of the master roll before use; the concept of the outer peripheral length of the master roll used to some extent). In the present embodiment, it is 20 mm or more and 150 mm or less ( Claims 4 and 5). Length L2 of stopper 100b as the other end of sheet member 100
Is set to a size that extends in the winding direction of the master 64, goes around the outer circumferential surface of the master 64, and overlaps the sheet members 100 beyond the front end portion 64a of the master 64. It is stopped by the seal 102 (claim 1).

The length L1 of the sandwiching portion 100a is 20 m
m, the sheet material 1 from the master roll
00 is easily removed, and the master 64 becomes loose. If the length L1 of the sandwiching portion 100a is 150 mm, it is possible to prevent detachment from the master roll and to obtain a stopping function with a minimum length. Further, the sheet member 10
The width W1 of the master roll 0 in the axial direction is set to be at least 1/3 of the width W2 of the master 64 in the same direction and within the same range as the width W2 of the master 64 (claim 6). The width W1 of the sheet member 100 is equal to the width W2 of the master 64.
If it is not more than の of the above, the both ends of the master 64 may be bent or the sheet member 100 may be displaced. If the width W1 of the sheet member 100 is made equal to the width W2 of the master 64, problems such as breakage and displacement can be prevented, and the protection of the master 64 can be maximized.

As the material of the sheet member 100, a Japanese paper type or PET type material can be adopted. In the present embodiment, the surface of the sheet member 100 is set to be rougher than the surface of the master 64 (claim 8). The thickness of the sheet member 100 is set to 100 μm or less (claim 7). 1
When the thickness is larger than 00 μm, the master 64 is easily creased by the edge of the sheet member 100.

In the present embodiment, the master 64
As shown in (a), a porous resin film 202 made of a thermoplastic resin is laminated as a support sheet on one surface of a thermoplastic resin film 200 (claim 2). The porous resin film 202 includes a resin film component 202a.
And a gap 202b. Porous resin film 2
02 is formed by depositing and coagulating a resin dissolved in a solvent, and has a structure having a large number of voids 202b inside and on the surface of the film. From the viewpoint of ink permeability, it is desirable that the gap 202b be continuous in the thickness direction in the film and be penetrated in the ceiling direction when the thermoplastic resin film 200 is used as a floor.

At the boundary between the porous resin film 202 and the thermoplastic resin film 200, the resin film component 202a of the porous resin film 202 covers the thermoplastic resin film 200 as long as the perforation by the thermal head 74 is not hindered. May be closed. The thickness of the resin constituting the porous resin film 202 that covers the thermoplastic resin film 200 and does not hinder the perforation by the thermal head 74 varies depending on the type of the resin, the thermal sensitivity of the thermoplastic resin film 200, and the like. The thickness combined with the plastic resin film 200 is 7 μm or less.

The thickness of the porous resin film 202 as a support is 5 μm or more and 50 μm or less, preferably 6 μm or more and 20 μm or less. If the thickness is less than 5 μm, it is difficult to obtain sufficient film strength, the porous resin film 202 is hardly left behind the perforated portion after perforation by the thermal head 74, and the amount of ink transferred is not controlled, and the back stain on the printed matter is poor. Easy to be. In addition, the effect of the porous resin film 202 for suppressing the amount of ink transferred is greater as the film is thicker, and the amount of ink transferred to printing paper during printing can also be adjusted by the thickness of the porous resin film 202. The porous resin film 202 is provided on the thermal head 74.
In order to more effectively perforate the porous resin film 202 due to the above, it is desirable that at least a part thereof, that is, a portion in contact with the thermoplastic resin film 200 be softened at a temperature of 150 ° C. or less. The pore size, shape,
A pigment may be included in the porous resin film 202 in order to adjust strength, stiffness, and the like.

The plastics which are the main components of the material of the porous resin film 202 include polyethylene, polypropylene, polybutene, styrene resin, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetal,
Vinyl resin such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, styrene-acrylonitrile copolymer, etc., polyacrylonitrile, polyacrylic plastic, diene plastic, polybutylene, nylon, etc. Polyamide, polyester, polyphenylene oxide, (meth) acrylate ester, polycarbonate, polyacetal, fluorine resin, polyurethane plastic, various natural plastics, natural rubber plastics, various thermoplastic elastomers, acetylcellulose, acetylbutylcellulose,
Examples include cellulose derivatives such as acetylpropylcellulose, microbial plastics, and copolymers containing these polymers. In addition, various fatty acids, various carbohydrates such as wax, and various proteins can also be used.

A filler may be added to the resin solution in the manufacturing process of the porous resin film 202, if necessary. This addition affects the shape, strength, and pore size of the porous resin film formed during the drying process. Specifically, zinc oxide, titanium dioxide, calcium carbide,
Inorganic compounds such as silica; and organic polymer particles such as polyvinyl acetate, polyvinyl chloride, and polymethyl acrylate. Microcapsules and Matsumoto Microsphere (Matsumoto Yushi Seiyaku Co., Ltd.) can also be used effectively. Further, 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 202 within a range that does not hinder perforation.

As the thermoplastic resin film 200 in the present embodiment, a film conventionally used for a heat-sensitive stencil master for heat-sensitive stencil printing, such as a vinyl chloride-vinylidene chloride copolymer film, a polypropylene film and a polyester film, is used. it can. The thickness of the film is
0.5 to 10 μm, more preferably 1.0 to 7.0
μm. If the thickness is less than 0.5 μm, it is too thin to apply the resin liquid.
4 makes it difficult to pierce. A stick prevention layer for preventing sticking with the thermal head 74 can be provided on the surface of the film. In this case, as the stick inhibitor to be used, those generally used in conventional heat-sensitive stencil masters for heat-sensitive stencil printing can be used. For example, a silicone release agent, a fluorine release agent, a phosphate ester surfactant, and the like can be used.

The image density of a printed image is determined by the amount of ink oozing from the master 64. The amount of ink that oozes out of the master 64 is proportional to the opening area of each minute hole of the thermoplastic resin film 200 constituting the perforation pattern formed in the master 64 and the gap 202 b on the hole of the porous resin film 202. I do. Therefore, a printed image having a high image density can be obtained by enlarging the individual holes of the thermoplastic resin film 200 and the porous resin film 202 forming the perforation pattern, as shown in FIG. As shown in FIG. 7B, a printed image with a low image density can be obtained by reducing the individual holes of the thermoplastic resin film 200 and the porous resin film 202 that form the perforation pattern. In other words, the punching energy corresponding to the temperature of each heat generating portion of the thermal head 74, that is, the size of the holes of the punching pattern for obtaining the optimum print image is determined according to the image density of the desired print image. be able to.
The master 64 may be composed of only a thermoplastic resin film (claim 3). Further, a porous fiber film made of a fibrous substance such as hemp may be laminated on the surface of the porous resin film opposite to the film.

Next, the method of replacing the master 64 and the operation of the plate making unit 8 will be described. When replacing the master 64, the master making unit 8 is pulled out of the apparatus main body, the remaining core material 65 is removed, flanges are attached to both ends of a new master roll, and the master making unit 8 is set in the master setting unit (not shown). set. After setting, the seal 102 is peeled off to remove the sheet member 100, and the leading end 64a of the master 64 is removed.
And push it into the nip of the master set roller 68. Thereafter, the plate making unit 8 is mounted on the apparatus main body.
When the plate making unit 8 is mounted, a mounting switch (not shown) is turned on, and the leading end 64a of the master 64 is sent by the master set roller 68, the platen roller 76, and the conveying roller pair 78. Is detected, the sheet is conveyed a predetermined distance, and the operation stops. This operation is called master auto loading, and is automatically performed when the plate making unit 8 is mounted on the apparatus main body. In this automatic loading, the thermal head 74 is not driven, and the master 64 is sent without plate-making.

The master 64 having undergone plate making is accommodated in a flexible box 88 and cut by a master cutting means 80 at a position corresponding to one plate length. The master 64 stored in the flexible box 88 is transported by a transport roller pair 84 that is driven to rotate in accordance with the opening and closing timing of the clamper 22 of the plate cylinder 6, and is wound around the outer peripheral surface of the plate cylinder 6.

[0036]

According to the first aspect of the present invention, the sheet member is sandwiched between the lower surfaces of the end portions of the roll-wound master and the outer peripheral surface is stopped by the sheet member. It is possible to prevent winding deviation during handling of the master such as during transport, storage, and when exchanging the master in the plate making unit, and it is possible to prevent the product quality of the master from deteriorating.

According to the second aspect of the present invention, the waist is low,
Even if the master has high smoothness, it is possible to prevent the winding from being displaced when the master is handled, such as when transporting, storing, or exchanging the master in the plate-making unit, and the product quality of the master can be prevented from deteriorating.

According to the third aspect of the present invention, the waist is low,
Even if the master has high smoothness, it is possible to prevent the winding from being displaced when the master is handled, such as when transporting, storing, or exchanging the master in the plate-making unit, and the product quality of the master can be prevented from deteriorating.

According to the fourth aspect of the present invention, since the sandwiching length of the sheet member in the winding direction of the master is set to be equal to or less than the outer peripheral length of the master roll, the sheet member can be easily pulled out when the master is used. Can be

According to the fifth aspect of the present invention, the sandwiching length of the sheet member in the winding direction of the master is 20 mm.
As described above, since the configuration is 150 mm or less, it is possible to prevent the sheet member from coming off and causing the loosening of the master, and to easily pull out the sheet member when using the master. Further, the sheet member can be firmly wound into the master, and the displacement of the sheet member can be prevented.

According to the sixth aspect of the present invention, the width of the sheet member in the axial direction of the master roll is not less than 1/3 of the width of the master in the same direction and within a range equivalent to the width of the master. Accordingly, it is possible to prevent the both ends of the master roll from being broken, to prevent the sheet member from being displaced, and to protect the master.

According to the seventh aspect of the present invention, since the thickness of the sheet member is 100 μm or less, it is possible to prevent the master from breaking at the end face of the sheet member.

According to the eighth aspect of the present invention, since the surface of the sheet member is rougher than the surface of the master, it is possible to prevent winding deviation even if the master has high smoothness.

[Brief description of the drawings]

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

FIG. 2 is a schematic front view of a plate making unit.

FIG. 3 is a control block diagram.

FIG. 4 is a perspective view of a master wound in a roll shape.

FIG. 5 is a perspective view of a state before the sheet member is wound around a master roll.

FIG. 6 is a front view of a master wound in a roll shape.

7A and 7B are schematic cross-sectional views showing a master, where FIG. 7A shows a state before punching, FIG. 7B shows a punching state when printing density is low, and FIG. 7C shows a state when printing density is high. It is a figure showing a perforated state.

[Explanation of symbols]

 64 Master 64a Tip end 64b Master outer peripheral surface 100 Sheet member 100b Stopper as the other end of the sheet member 200 Thermoplastic resin film 202 Porous resin film L1 Sheet member sandwiching length W1 Sheet member width W2 Master width

Claims (8)

[Claims] In a stencil printing master wound in a roll, a sheet member is sandwiched between a leading end portion of the master and an outer peripheral surface of the master, and the other end of the sheet member extends in a winding direction of the master. A stencil printing master, wherein the stencil printing master extends so as to make a round around the outer peripheral surface of the master, and the sheet members overlap with each other beyond the front end of the master, and the overlapping portion is stopped. 2. The stencil printing master according to claim 1, wherein said master has a structure in which a porous resin film is laminated on one surface of a thermoplastic resin film. For master. 3. A stencil printing master according to claim 1, wherein said master comprises only a thermoplastic resin film. 4. The stencil printing master according to claim 1, wherein a sandwiching length of the sheet member in a winding direction of the master is equal to or less than an outer peripheral length of the master roll. Stencil printing master. 5. The stencil printing master according to claim 1, wherein a sandwiching length of the sheet member in a winding direction of the master is not less than 20 mm and not more than 150 mm. Stencil printing master. 6. A stencil printing master according to claim 1, wherein the width of the sheet member in the axial direction of the master roll is at least 1/3 of the width of the master in the same direction. And a stencil printing master characterized by being within a range equivalent to the width of the master. 7. A stencil printing master according to claim 1, wherein said sheet member has a thickness of 10%.
A stencil master having a thickness of 0 μm or less. 8. The stencil printing master according to claim 1, wherein a surface of said sheet member is rougher than a surface of said master.