JP3309001B2 - Base paper for heat-sensitive stencil printing and production method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive stencil sheet and a method for producing the same, and more particularly, to a thermal head,
The present invention relates to a heat-sensitive stencil sheet having excellent heat-perforation properties such as a xenon plate making method and a flash valve method, and a method for producing the same.

[0002]

2. Description of the Related Art A conventional heat-sensitive stencil sheet is composed of a thermoplastic resin film such as a polyester film and a porous support adhered to one surface of the film with an adhesive. The plate is made by bringing a thermal head into contact with the film and thermally melting the film by the heat to form an opening corresponding to the image portion of the document.

[0003] However, in such a base paper, an adhesive layer for bonding the thermoplastic resin film and the porous support is formed between the thermoplastic resin film and the porous support.
There has been a problem that the perforation of the film due to the heat of the thermal head is easily hindered, and the adhesive layer is dissolved by the organic solvent contained in the ink during printing, thereby lowering the printing durability of the base paper. In the production of the base paper, if the coating amount of the adhesive is too large, the voids of the porous support are filled with the adhesive layer, and the perforation sensitivity of the film is reduced, the plate making performance is reduced, and ink passing On the other hand, if the coating amount of the adhesive is too small, problems such as low adhesive strength and poor printing durability occur, and it is difficult to control the production process.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a thermal head, a xenon plate making system, a flash valve system, etc., which are excellent in film piercing and printing durability in heat-sensitive stencil printing. It is an object of the present invention to provide a method for producing a heat-sensitive stencil sheet which can easily control the base paper and the manufacturing process.

[0005]

According to a first aspect of the present invention, there is provided a heat-sensitive stencil printing paper comprising a thermoplastic resin film and a porous support, wherein the porous support has a sheath-core structure and a sheath component thereof. Is a fiber composed of components having an affinity for the thermoplastic resin film is used for all or a part thereof
A heat-sensitive stencil printing base paper characterized in that a screen woven is used and the screen is joined to the thermoplastic resin film via a sheath component.

According to a second invention of the present application, a thermoplastic resin film has a sheath-core structure comprising a low-melting component and a high-melting component,
A screen in which the sheath component is woven by using all or a part of fibers having an affinity for the thermoplastic resin film at a temperature higher than the softening point of the sheath component and lower than the melting point of the thermoplastic resin film. A method for producing a heat-sensitive stencil printing base paper, which comprises bonding by thermocompression bonding.

[0007] In the present invention, as the porous support ,
It has a sheath core structure, and the sheath component is a thermoplastic resin fill
Screen woven using conjugate fiber with
And the screen and the thermoplastic resin film are directly joined by a line and a point contact via a sheath component, so that an adhesive layer does not exist between the film and the screen as in the related art. Therefore, it is possible to improve the smoothness of the film surface of the laminated base paper, as well as to improve the adhesion with the thermal head during plate making, thereby improving the heat transfer efficiency, and to greatly improve the plate making sensitivity. , Yu
An improved film perforation is obtained . Further, since the surface of the base paper is smooth, the pressure applied per unit area at the time of printing becomes uniform, the printing becomes uniform, and an image more faithful to the original can be obtained. In addition, a screen and
Form a uniform adhesive layer between thermoplastic resin films
Process is not required, making the management of the manufacturing process easier.
You.

[0008] As the thermoplastic resin film used in the present invention, a film of polyester, polyvinyl chloride, polypropylene or the like is usually used. 8 μm.

The screen used in the present invention is composed of a woven fabric woven by using all or a part of composite fibers having a sheath-core structure, and the sheath component has an affinity for the thermoplastic resin film. Consists of components. The component having an affinity for the thermoplastic resin film refers to a component which has a sufficient bonding force with the film by alternative means such as thermocompression bonding or light irradiation and is not easily peeled off. Such a component may be the same as the thermoplastic resin film.

When the above-mentioned screen is joined to a thermoplastic resin film by heating, the melting point of the sheath component is lower than the core components of the thermoplastic resin film and the composite fiber. For example, when using a polyethylene terephthalate film as a thermoplastic resin film, as a sheath component, a copolymerized polyester having a lower melting point than this, for example, other monomers and reaction components such as polyethylene glycol were copolymerized during the polymerization of polyethylene terephthalate. Are preferably used. Other monomers or reaction components include dicarboxylic acids such as isophthalic acid, adipic acid and dimer acid, low molecular weight glycols such as diethylene glycol and butanediol, and polyalkylene glycols such as polyethylene glycol and polytetramethylene glycol. .

The core component of the conjugate fiber is not particularly limited as long as it does not melt by thermocompression bonding at the time of bonding the screen and the thermoplastic resin film. For example, polyester, especially polyethylene terephthalate is preferably used in terms of price and the like. Can be The use ratio of the sheath component is such that the sheath component of the multilayer fiber is softened or hot-melted by thermocompression bonding and adheres to the thermoplastic resin film.
The amount may be such that the holes in the screen are not crushed by deformation due to softening or by a hot melt. Usually, the cross-sectional area ratio of the sheath component / core component is preferably in the range of 5/95 to 50/50. The composite fiber cross-sectional shape may be circular or modified. The cross-sectional shape and the number of cores are not necessarily
It does not need to be a book, and can be selected and determined as needed.

The conjugate fiber is obtained by a conventional melt spinning method using a known sheath-core composite spinning nozzle, and is woven by a known method using all or part of the conjugate fiber (filament). Thus, a screen used in the present invention can be obtained. The screen may be composed of only composite fibers. However, for some of the fibers, for example, composite fibers may be used only for the warp or weft, or every other warp or weft may be used. It may be used every other book. As the fiber used other than the conjugate fiber, for example, a normal fiber made of the polyester having the high melting point component described above can be used. The aperture of the screen is preferably in the range of 70 mesh to 400 mesh from the viewpoint of ink passage and image quality, and the thickness thereof is preferably in the range of 40 μm to 200 μm.

The heat-sensitive stencil sheet of the present invention is produced by laminating a thermoplastic resin film and a screen as a porous support by thermocompression bonding using, for example, a nip roll. The temperature and pressure of thermocompression bonding are
Depending on the material of the thermoplastic resin film or screen, it is determined to be heated to a temperature equal to or higher than the softening point of the low melting point component of the composite fiber and lower than the melting point of the high melting point component and the thermoplastic resin film as described above. . For example, in the case of heat-sensitive stencil printing paper in which a polyester film is bonded to a cloth made of a polyester composite yarn using a copolyester as a low-melting point component, a nip pressure of 1 between a metal roll and a silicone rubber roll heated to 120 ° C. .
Thermocompression bonding can be performed at 8 kg / cm ² .

[0014]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Example 1 A screen made of a polyester fiber having a multifilament sheath-core structure (trade name: TP-70, manufactured by Japan Special Textile Co., Ltd.)
0, 70 mesh, thickness 110 μm) and thickness 2 μm
Of polyethylene terephthalate film, and passed through a metal roll and a silicone rubber roll heated at 120 ° C. at a nip pressure of 1.8 kg / cm ² to bond the screen and the film to produce a heat-sensitive stencil sheet. The surface of the fiber constituting the screen was uniformly bonded to the film by heat fusion. Dimethylsilicone oil was applied to the film surface of the base paper and mounted on an integrated plate-making and printing machine (RC-115) manufactured by Riso Kagaku Kogyo Co., Ltd. to perform plate-making printing. As a result, a good printed image was obtained. .

Example 2 Polyester composite fiber having a sheath-core structure (monofilament)
(Manufactured by NBC Industries, mesh 200 mesh, thickness 75 μm) is superimposed on a polyethylene terephthalate film having a thickness of 2 μm, and a nip pressure between the metal roll and the silicone rubber roll heated to 120 ° C. is 1.8 kg / cm. ^The screen and the film were bonded together by passing through step ² to prepare a heat-sensitive stencil printing base paper. Dimethyl silicone oil is applied to the film surface of the base paper, and an integrated plate-making printing machine (RC-11, manufactured by Riso Kagaku Kogyo Co., Ltd.) is used.
When plate-mounting printing was performed by mounting the plate on 5), a good printed image could be obtained.

Example 3 Polyester composite fiber (monofilament) having a sheath-core structure obtained by subjecting a low-melting component (copolyester) and a high-melting component (homopolyester) to composite spinning at a ratio (weight ratio) of 10/90. Is used as a weft thread, and a normal polyester fiber is used as a warp thread, and the screens of 135 mesh, 200 mesh and 420 mesh are used (the thickness is 90, respectively).
70, 60 μm). These screens are superimposed on a polyethylene terephthalate film having a thickness of 2 μm and passed between a metal roll and a silicone rubber roll heated to 120 ° C. at a nip pressure of 1.8 kg / cm ² , and the screen and the film are bonded to each other to form a heat sensitive stencil. Printing base papers were respectively produced. Dimethylsilicone oil was applied to the film surface of these base papers, and mounted on an integrated plate-making and printing machine (RC-115) manufactured by Riso Kagaku Kogyo Co., Ltd. to perform plate-making printing. As a result, a good printed image could be obtained. Was.

Comparative Example 1 A screen made of polyethylene fiber having a softening point of 105 ° C. (NB
C Industrial Co., Ltd., nip strong net, 150 mesh) and a 2 μm polyethylene terephthalate film were superimposed and thermocompression-bonded in the same manner as in Example 1. However, the fibers constituting the screen were softened to form a film, and the ink was completely removed. Was unable to pass.

Comparative Example 2 A screen made of polypropylene fiber having a softening point of 140 ° C. (N
A superposition of 2 μm polyethylene terephthalate film and a nip strong net (150 mesh, manufactured by BC
When passing between a metal roll and a silicone rubber roll heated to 0 ° C. in the same manner as in Example 1, the fibers constituting the screen were deformed, the bonding strength between the screen and the film was extremely weak, and the film was picked lightly. And peeled off.

Comparative Example 3 Polyester Screen (trade name: TN, manufactured by NBC Industries, Ltd.)
0.200 S) and a polyethylene-based multilayer film (trade name: 212.T, manufactured by Dainippon Ink and Chemicals, Inc.), and a nip pressure of 1.8 kg / cm ² between a metal roll and a silicone rubber roll heated to 100 ° C. Let it pass. The surface layer of the film was softened and a good bonded product could be obtained. However, when dimethyl silicone was applied to the film surface and plate-making printing was performed in the same manner as in Example 1, the film was not perforated at all. No image could be obtained.

[0020]

According to the first aspect of the present invention, since the screen and the thermoplastic resin film can be directly bonded without forming an adhesive layer, excellent film perforation and printing durability can be obtained. Can be According to the second aspect of the present invention, since the step of forming an adhesive layer between the screen and the thermoplastic resin film is unnecessary, the management of the manufacturing process is facilitated.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-184888 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41N 1/24

Claims (2)

(57) [Claims] 1. A heat-sensitive stencil printing paper comprising a thermoplastic resin film and a porous support, wherein the porous support has a sheath-core structure, and the sheath component has an affinity for the thermoplastic resin film. A heat-sensitive stencil printing base paper characterized in that a screen woven using fibers composed entirely of components is used in whole or in part, and the screen is joined to the thermoplastic resin film via a sheath component. . 2. A thermoplastic resin film having a sheath-core structure comprising a low-melting-point component and a high-melting-point component, wherein the sheath component uses, as a whole or in part, fibers having an affinity for the thermoplastic resin film. A method for producing heat-sensitive stencil printing paper, comprising bonding the woven screen by thermocompression bonding at a temperature higher than the softening point of the sheath component and lower than the melting point of the thermoplastic resin film.