JP2001039049A - Film for thermosensitive stencil printing base paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve perforation sensitivity, imaging properties, and plate releasing properties by forming a film for the thermosensitive stencil printing base paper from at least two kinds of thermoplastic resins and using a polyetherimide for at least one of the resins. SOLUTION: In the production of a film for thermosensitive stencil printing base paper to be perforated by a thermal head, etc., at least two kinds of thermoplastic resins are used, and at least one of them is made a polyetherimide. By using these resins as raw materials, the thermal properties, especially heat shrinkage, are improved so that a high sensitivity film excellent in low-energy perforation sensitive to heat from the thermal head can be obtained. A thermoplastic film of a polyester, its copolymer or its blend is most preferable. Preferably 0.1-50 wt.% of the polyetherimide is incorporated.

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 film for perforated stencil printing made by a thermal head or a halogen lamp, a xenon lamp, a flash lamp, a laser beam or the like. And a heat-sensitive stencil film for a stencil sheet which is excellent in curl property and stencil discharge property of the base paper.

[0002]

2. Description of the Related Art Conventionally, as heat-sensitive stencil base paper,
A porous support composed of natural fiber, chemical fiber or synthetic fiber, or thin paper, nonwoven fabric, gauze, etc., made of a thermoplastic resin film such as vinylidene chloride film, polyester film, polypropylene film, etc. Those having a laminated structure are known (for example, JP-A-51-2513 and JP-A-57-2513).
182495).

However, in recent years, high resolution has been required for printed materials. For example, attempts have been made to increase the number of perforations per unit area by shortening the thermal head heating cycle. In such a case, it is necessary to reduce the energy supplied to the individual heads in order to obtain an appropriate size of perforations in a short time and to reduce the load on the thermal head and extend the life. Is desired to be perforated with low energy, that is, to increase the sensitivity of the film.

In addition, good transportability and plate discharging property in a printing press are required, and problems such as plate making defects and misalignment of printed images caused by troubles such as plate improper printing and master clogging during transport and plate discharging are required. It is necessary that it does not occur.

Conventionally, a film having improved printing characteristics by specifying the thermal characteristics of the film (Japanese Patent Laid-Open No. Sho 62-28)
2984, JP-A-3-39294, JP-A-4-224925, etc.)
Films in which the composition of the polymer is specified for the purpose of increasing the sensitivity of the film (JP-A-2-158391, JP-A-10-158
Japanese Patent Application Laid-Open No. 119453/1992) has been proposed, but is insufficient in terms of perforation sensitivity, image quality, and stencil discharge, especially in a high-resolution printing machine requiring a large number of perforations per unit area. At the same time, something satisfying was demanded.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a film for a heat-sensitive stencil sheet which is excellent in perforation sensitivity and excellent in image quality and plate discharging property.

[0007]

Means for Solving the Problems The present inventors diligently studied to solve the above problems. As a result, it is made of two or more kinds of thermoplastic resins, and at least one of them is made of polyetherimide, so that the perforation sensitivity is excellent, and the image quality can be improved without contaminating the thermal head, the inside of the printing machine, and the printing paper.
It has been found that a film for heat-sensitive stencil printing base paper having excellent transportability can be obtained, and the present invention has been completed.

That is, the film for heat-sensitive stencil printing paper according to the present invention comprises two or more kinds of thermoplastic resins, and at least one kind is a polyetherimide.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.

[0010] The film for heat-sensitive stencil printing base paper of the present invention comprises:
Consisting of two or more thermoplastic resins, at least one of
The type must be a film made of polyetherimide. By using a raw material consisting of polyetherimide and another kind of thermoplastic resin, the thermal characteristics of the film, especially the heat shrinkage characteristics, are improved, and the perforation at low energy is sensitive to the heat given by the thermal head. High sensitivity film can be obtained.

The thermoplastic resin used in the film for heat-sensitive stencil printing of the present invention includes polyetherimide, polyester, polyamide, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, their respective copolymers, and their copolymers. Blends and the like, among which polyester, and a copolymer thereof, or a thermoplastic film using the blend, film forming properties,
It is most preferable from the viewpoint of the strength and elongation characteristics.

The polyetherimide used in the film for heat-sensitive stencil printing paper of the present invention is a polymer containing an aliphatic, alicyclic or aromatic ether unit and a cyclic imide group as a repeating unit. The polymer is not particularly limited as long as it has a property. For example, U.S. Pat. No. 4,141,927 and Japanese Patent No. 2,622,678.
No. 2,606,912, Japanese Patent No. 260691
No. 4, Japanese Patent No. 2596565, Japanese Patent No. 259
No. 6566, Japanese Patent No. 2598478, polyetherimide, Japanese Patent No. 2598536, Japanese Patent No.
No. 599171, Japanese Unexamined Patent Publication No. 9-48852, Japanese Patent No. 256556, Japanese Patent No. 25664636, Japanese Patent No. 25664637, and Japanese Patent No. 256354.
No. 8, Japanese Patent No. 2563547, Japanese Patent No. 255
No. 8341, Japanese Patent No. 2558339 and Japanese Patent No. 2834580. As long as the effects of the present invention are not impaired, the main chain of the polyetherimide has a cyclic imide, a structural unit other than an ether unit, for example, an aromatic, aliphatic, alicyclic ester unit, or an oxycarbonyl unit. It may be contained.

In the present invention, the polyetherimide preferably contains 0.1 to 50% by weight.
More preferably 1 to 40% by weight, even more preferably 5 to
30% by weight.

When the polyetherimide content is less than 0.1% by weight, the heat shrinkage of the film at 65 ° C. becomes large,
A film with a large change with time, poor curl properties, poor transport properties and poor plate discharge properties may be obtained. On the other hand, if the polyetherimide content exceeds 50% by weight, the extensibility is reduced, and the extruded polymer is likely to contain unmelted materials. Care must be taken because it may be difficult to obtain the film of the invention. The content of the polyetherimide in the film can be determined by an appropriate measurement method.

Next, an example of obtaining the polyetherimide content in the film will be described, but the present invention is not limited to this example.

The weighed polyester film (Xg) is dissolved in a mixed solution of hexafluoroisopropanol and chloroform and then reprecipitated with acetone to obtain polyester and polyetherimide powder particles. The polyetherimide component is eluted in chloroform from the obtained powdery particles, filtered out, and weighed (Yg).

From the formula (1), the content of the polyetherimide contained in the film is calculated.

Polyetherimide content = Y / X × 100 [%] Formula (1) The polyester used for the film for heat-sensitive stencil printing paper of the present invention is an aromatic dicarboxylic acid or an aliphatic dicarboxylic acid. Polyester containing diol as a main component.

The aromatic dicarboxylic acids include, for example, terephthalic acid, isophthalic acid, phthalic acid, 1,4
-Naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-
Biphenyl dicarboxylic acid, 4,4'-biphenyl ether dicarboxylic acid, 4,4'-biphenyl sulfone dicarboxylic acid and the like can be used. Among them, terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid can be preferably used.

As the aliphatic dicarboxylic acid component, for example, adipic acid, suberic acid, sebacic acid, dodecanedioic acid and the like can be used.

These acid components may be used alone or in combination of two or more. Further, oxyacids such as hydroxybenzoic acid may be partially copolymerized. Also,
As the diol component, for example, ethylene glycol, 1,
2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,
4-butanediol, 1,5-pentanediol, 1,
6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4
-Cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2'-bis (4'-β-hydroxyethoxyphenyl) propane, and the like can be used. Among them, ethylene glycol, 1,4-butanediol, 1,6-
Hexanediol is preferably used. These diol components may be used alone or in combination of two or more.

The polyester used for the heat-sensitive stencil film of the present invention is preferably polyethylene terephthalate, a copolymer of ethylene terephthalate and ethylene isophthalate, a copolymer of ethylene terephthalate and ethylene naphthalate, hexamethylene Copolymers of terephthalate and cyclohexane dimethylene terephthalate, blends of polyethylene terephthalate and polybutylene terephthalate, copolymers, and the like can be given. Particularly preferred from the viewpoint of perforation sensitivity and stretchability are copolymers of ethylene terephthalate and ethylene isophthalate, copolymers of ethylene terephthalate and ethylene naphthalate, and copolymers of ethylene terephthalate and butylene terephthalate.

The heat-sensitive stencil film of the present invention preferably has a crystal melting energy (ΔHu) of 5 to 45 J.
/ G, more preferably 10 to 45 J / g, particularly preferably 15 to 42 J / g. When ΔHu is 5 to 45 J / g, the variation in perforation sensitivity of the film is small.

The heat shrinkage of the film for heat-sensitive stencil printing paper of the present invention is determined by a required perforation method.
The heat shrinkage in the longitudinal direction of the film when treated at 65 ° C. for 60 minutes is preferably 1.5% or less. It is more preferably at most 1.0%, further preferably at most 0.8%. If the heat shrinkage in the longitudinal direction of the film after treatment at 65 ° C. for 60 minutes is 1.5% or less, the curl at room temperature of the heat-sensitive stencil sheet prepared using this film becomes good, and the This is preferable because the transportability of the resin becomes better, and the change with time hardly occurs, and the long-term storage property is enhanced.

It is preferable that the heat shrinkage in the longitudinal direction of the film after treatment at 100 ° C. for 30 minutes is 8% or more. It is more preferably at least 12%, further preferably at least 15%. When the heat shrinkage in the longitudinal direction of the film after treatment at 100 ° C. for 30 minutes is 8% or more, it is preferable because the pore diameter is large and uniform, and the image quality is easily improved.

The thickness of the film for heat-sensitive stencil printing paper of the present invention is preferably from 0.1 in view of perforation sensitivity and film forming stability.
10 μm, more preferably 0.2 to 7 μm, and still more preferably 0.3 to 5 μm.

The heat sensitive stencil film of the present invention is
From the viewpoint of enhancing the perforation sensitivity and improving the image quality, when the film was heated from room temperature to the melting point or the decomposition point and the heat shrinkage stress in the width direction and the longitudinal direction was measured, the peak value of the heat shrinkage stress was 300 g / mm ^2. It is preferable that it is above. More preferably, it is 400 g / mm ² or more, and still more preferably, 450 g / mm ² or more.

The glass transition temperature of the film for heat-sensitive stencil printing base paper of the present invention is preferably from 50 to 170 from the viewpoint of enhancing perforation sensitivity.
It is preferably in the range of ° C. More preferably 70 to
The temperature is 150 ° C, more preferably 75 to 140 ° C.

The melting temperature of the film for heat-sensitive stencil printing base paper of the present invention is preferably from 130 to 320 ° C. from the viewpoint of enhancing perforation sensitivity. More preferably, it is 140 to 310 ° C, more preferably 150 to 300 ° C.

The intrinsic viscosity of the film for heat-sensitive stencil printing paper of the present invention is usually 0.1 in view of the strength and film forming property of the film.
4 dl / g or more is preferable. More preferably 0.5 to
1.2 dl / g, more preferably 0.55 to 1.0 d
1 / g.

The melt viscosity of the film for heat-sensitive stencil printing paper of the present invention is preferably 500 to 20,000 poise. More preferably, 1000-15000po
is. Melt viscosity is 500-20,000 pois
The case of e is preferable because the fluidity of the resin forming the film is good, the perforation is high, the perforation diameter is easy to be uniform, and the image quality is high. If the ratio exceeds these ranges, the fluidity of the resin is deteriorated, and the performance may be deteriorated, such as a failure in obtaining a target perforation diameter and a decrease in image quality.

In the film for heat-sensitive stencil printing base paper of the present invention, in order to improve the workability in the film winding step, the coating in forming the base paper, the laminating step and printing, or between the thermal head and the film in hot perforation. In order to prevent fusion, it is preferable that the surface is roughened to impart an appropriate slip property to the film, and inorganic particles and organic particles as long as the effects of the present invention are not impaired, and other various additives, For example, a plasticizer, a weathering agent, an antioxidant, a heat stabilizer, a lubricant, an antistatic agent, a whitening agent, a coloring agent, a conductive agent, and the like may be added.

Specific examples of the inorganic particles include silicon oxide,
Oxides such as aluminum oxide, magnesium oxide, and titanium oxide; complex oxides such as kaolin, talc, and montmorillonite; carbonates such as calcium carbonate and barium carbonate; sulfates such as calcium sulfate and barium sulfate; barium titanate; Titanate such as potassium, phosphate such as tertiary calcium phosphate, dibasic calcium phosphate, and monocalcium phosphate can be used, but not limited thereto. These may be used in combination of two or more depending on the purpose.

Specific examples of the organic particles include polystyrene or crosslinked polystyrene particles, vinyl particles such as styrene / acrylic / acrylic crosslinked particles, styrene / methacrylic / methacrylic crosslinked particles, benzoguanamine / formaldehyde, silicone, and polytetrafluoroethylene. Although particles such as fluoroethylene can be used, the particles are not limited thereto, and any particles may be used as long as at least a part of the particles constituting the particles is organic polymer fine particles insoluble in polyester.

The organic particles preferably have a spherical particle shape and a uniform particle size distribution from the viewpoint of smoothness and uniformity of formation of projections on the film surface.

The particle size, blending amount, shape and the like of these particles can be selected according to the application and purpose.
The average particle size is preferably in the range of 0.01 μm to 3 μm, and the blending amount is preferably in the range of 0.01 to 6% by weight.

The heat-sensitive stencil film of the present invention is
An unstretched or unoriented film may be used, but effects such as strength and film-forming stability are more remarkably exhibited by using an oriented film that is uniaxially or biaxially stretched and heat-set by an appropriate stretching method. In particular, a film formed by a stenter sequential biaxial stretching method is preferable in terms of thickness uniformity.

The heat-sensitive stencil sheet of the present invention is obtained by bonding the above-mentioned film for heat-sensitive stencil sheet to a porous support. With the porous support of the present invention,
It is a porous material made from natural fibers, synthetic fibers, etc. that can transmit the printing ink and does not substantially undergo thermal deformation under the heating conditions under which the film is perforated, and is made of paper, nonwoven fabric, woven fabric, gauze or Other porous bodies.

The porous support bonded to the heat-sensitive stencil film of the present invention is preferably a porous support made of a stretched thermoplastic fiber in view of mechanical strength and heat resistance. The basis weight of the porous support is preferably 2 to 20 g /
m ² , more preferably 3 to 15 g / m ² , particularly preferably 5 to 10 g / m ² . The basis weight is 2 to 20 g
/ M ² , ink permeability is good and image quality is good.
Further, when the basis weight is 5 to 20 g / m ² , more sufficient strength can be obtained.

The average fiber diameter of the fibers constituting the porous support is preferably 1 to 20 μm, and more preferably 2 to 20 μm.
To 15 μm, particularly preferably 2 to 10 μm. When the average fiber diameter is 1 to 20 μm, sufficient strength and heat resistance can be obtained, ink permeability is good, and white spots are less likely to occur during printing, which is preferable.

The crystal melting energy of the porous support (ΔH
u) is preferably from 20 to 65 J / g, more preferably from 30 to 65 J / g, from the viewpoint of plate discharging property and durability after plate making. In addition, the crystallinity of the porous support is preferably 20% or more, more preferably 30% or more, from the viewpoint of plate discharging property after plate making in perforation.

The porous support may have the same fiber diameter or a mixture of fibers having different fiber diameters. Further, the porous support is not limited to a single-layer structure, and may have a multilayer structure in which materials having different average fiber diameters are laminated stepwise.

The method for producing the heat-sensitive stencil sheet of the present invention will be described below, but the present invention is not limited thereto.

In the present invention, the film for heat-sensitive stencil printing paper can be manufactured by the following method. In the present invention, the heat-sensitive stencil film for stencil printing is, for example, after sufficiently drying the thermoplastic resin, supplied to an extruder, melted in an extruder at 150 to 350 ° C., and cast onto a cast drum by a T-die extrusion method. An unstretched film is obtained by extrusion.

At this time, the drying condition of the resin is Tg-30 ° C. of the resin in order to remove water and low molecular weight substances in the resin.
The drying is performed at a drying temperature not less than the melting point but not more than the melting point, and the pressure is reduced to 10 Torr or less, preferably for 3 hours or more, more preferably 5 Torr or less for 5 hours or more.

The extrusion conditions are preferably such that the resin is extruded at a lower temperature and a shorter residence time within a range that does not affect the molding of the unstretched film, in order to suppress the thermal decomposition of the resin.

In order to improve the adhesion between the melted film and the cooling roll, an electrostatic application adhesion method or a liquid surface application adhesion method is preferably employed. At this time, the unstretched film can have a desired thickness by adjusting the slit width of the die, the discharge amount of the polymer, and the rotation speed of the cast drum. The unstretched film can be biaxially stretched by simultaneously or successively biaxially stretching it with a roll or a tenter from the viewpoint of film forming stability and film thickness uniformity.

In the case of sequential biaxial stretching, the stretching order may be such that the film is stretched in the longitudinal direction, the width direction, or vice versa. Further, in the sequential biaxial stretching, stretching in the longitudinal direction and the stretching in the width direction can be performed in two or more steps. The stretching conditions of the film can be appropriately adjusted according to the desired heat shrinkage characteristics, orientation degree, strength and elastic modulus of the film, and can be carried out by any method. The stretching temperature of the film is preferably lower than the glass transition temperature (Tg) of the resin to be used-30 ° C or higher and the crystallization temperature of the resin + 30 ° C or lower. The stretching ratio in the longitudinal direction and the width direction of the film can be set to any value from 1.2 to 10 times that allows setting the stretching temperature lower, and is preferably 1.5 times or more. Either of the stretching ratio in the longitudinal direction and the stretching ratio in the width direction may be increased, and may be the same. It is also possible to simultaneously biaxially stretch the unstretched film so that the area magnification becomes 5 to 50 times.

The film thus obtained can be heat-treated by any method for the purpose of improving the strength, stability over time, and shrinkage characteristics. The heat treatment temperature is preferably lower than 30 ° C. or higher but lower than the melting point, more preferably 130 ° C.
° C or lower, more preferably 100 ° C or lower.
In addition, the heat treatment time can be arbitrarily set, but 1 second to 5 seconds.
Minutes. Preferably, it is performed in the range of 1 to 60 seconds. The heat treatment may be performed while the film is relaxed in the longitudinal direction and / or the width direction, and may be cooled stepwise.

The film of the present invention can be subjected to various surface treatments such as corona discharge treatment, chemical treatment, flame treatment, ultraviolet treatment, and plasma treatment in order to improve the adhesion to the porous support.

Further, if necessary, a coating treatment can be performed. By providing a release layer on the film, stick preventing properties and adhesion preventing properties with the document may be imparted, or adhesive properties with the porous support and antistatic properties may be imparted. In the heat-sensitive stencil printing paper of the present invention,
Adhesion between the thermoplastic film and the porous support made of thermoplastic fibers may be via an adhesive such as a vinyl acetate resin, an acrylic resin, a urethane resin, or a polyester resin. It may be adhered without. The method for bonding without the use of an adhesive is not particularly limited, but a method of laminating a thermoplastic film and a porous support made of thermoplastic fibers and performing thermocompression bonding is preferred.

The porous support used is preferably a biaxially stretched unstretched non-woven fabric made of thermoplastic fibers. The method of biaxial stretching may be any of a sequential biaxial stretching method and a simultaneous biaxial stretching method as in the case of the above-mentioned film. In the case of the sequential biaxial stretching method, the unstretched nonwoven fabric is generally stretched in the longitudinal direction and the transverse direction in general, but may be stretched in the opposite direction. The stretching ratio is not particularly limited and is appropriately determined depending on the type of the polymer to be used, but is preferably 2 to 8 times, and more preferably 3 to 8 times, each in the vertical and horizontal directions. After that, the porous support after the biaxial stretching may be heat-treated. The heat treatment temperature is preferably 50 to 150 ° C., and the heat treatment time is preferably 0.5 seconds to 10 minutes. Next, a heat-sensitive stencil sheet can be prepared by bonding a porous support made of a thermoplastic film and a thermoplastic fiber with an adhesive.

The method of thermocompression bonding of the porous support comprising a thermoplastic film and a thermoplastic fiber in the present invention is not particularly limited.
It is particularly preferable in view of the easiness of the process. In the present invention, the thermocompression bonding is preferably performed before the stretching step after the thermoplastic film is cast. Thermocompression temperature is 5
0 ° C to glass transition temperature (Tg) of thermoplastic fiber +20
C. is preferred. Next, co-stretching of a thermocompressed thermoplastic film and an unstretched nonwoven fabric made of thermoplastic fibers can also be preferably used. By co-stretching in the state of thermocompression bonding, the film and the porous support can be stretched integrally. In addition, by co-stretching both, the porous support made of thermoplastic fiber serves as a reinforcing member, and the thermoplastic film can be formed extremely stably without being broken.

Further, after the heat treatment, the film once cooled to 30 ° C. or less is heated under tension or without tension to 40 to 10 ° C.
An aging treatment of placing the film at a temperature of 0 ° C. for about 10 seconds to about 1 week can be performed to adjust the thermal characteristics of the film. This aging treatment may be incorporated in the film forming process as in the case of the heat treatment, but it is more preferable to perform such treatment on a roll-shaped film obtained by winding once after the heat treatment.

In the present invention, the above-mentioned “co-stretching” means that the unstretched nonwoven fabric is laminated with a film and then both stretched.

In the method of co-stretching in the present invention, biaxial stretching is preferred from the viewpoint of improving the perforation sensitivity of the film and the uniform dispersibility of the fibers forming the porous support made of thermoplastic fibers. The biaxial stretching may be either a sequential biaxial stretching method or a simultaneous biaxial stretching method. In the case of the sequential biaxial stretching method, stretching is generally performed in the order of the longitudinal direction and the transverse direction, but may be performed in the opposite direction. The stretching temperature is preferably between the glass transition temperature (Tg) of the polyester fiber used for stretching and the elevated crystallization temperature (Tcc). The stretching ratio is not particularly limited, and is appropriately determined depending on the type of the polymer for the thermoplastic film to be used and the perforation sensitivity required for the heat-sensitive stencil printing base paper, and the like.
About 5 times is appropriate. After biaxial stretching, the film may be stretched longitudinally, horizontally, or vertically and horizontally again. Further, it is also preferable to subject the heat-sensitive stencil printing base paper of the present invention to heat treatment after biaxial stretching. Further, after the heat-sensitive stencil sheet obtained by the treatment is once cooled to about room temperature,
Aging can be performed at a relatively low temperature of about 90 ° C. for about 5 minutes to about 1 week. When such aging is employed, curling and wrinkling are less likely to occur during storage of the heat-sensitive stencil sheet or in a printing machine, which is particularly preferable.

The base paper for heat-sensitive stencil printing of the present invention has a silicone oil, a silicone-based resin, a fluorine-based resin, a surfactant, an antistatic agent, in order to prevent fusing at the time of perforation on one side of the film to be in contact with the thermal head. Agents, heat stabilizers, antioxidants, organic particles, inorganic particles, pigments, dispersing aids, preservatives,
It is preferable to provide a thin layer made of an antifoaming agent or the like. The thickness of the thin layer for preventing fusion is preferably 0.005 to 0.4 μm.
m, more preferably 0.01 to 0.4 μm.

When a thin layer for preventing fusion is provided on the heat-sensitive stencil sheet of the present invention, the coating solution is applied in the form of a coating solution dissolved, emulsified or suspended in water, and then the water is dried. Is preferred. The coating may be performed before or after stretching the film. In order to make the effect of the present invention more remarkable, when performing sequential biaxial stretching such as transverse stretching after longitudinal stretching, before transverse stretching, and when performing simultaneous biaxial stretching, before stretching. It is particularly preferred to apply. The application method is not particularly limited, but application is preferably performed using a roll coater, a gravure coater, a reverse coater, a bar coater, or the like.
Before providing the thin layer for preventing fusion, an activation treatment such as a corona discharge treatment may be applied to the coated surface in air or other various atmospheres as necessary. [Method of measuring properties] (1) Melting temperature, crystallization temperature, melting energy (ΔH
u) As a differential scanning calorimeter (DSC), a robot DSC “RDSC220” manufactured by Seiko Denshi Kogyo Co., Ltd. is used.
SC / 5200 "on an aluminum pan
g of composition or film sample. This sample was once melted and rapidly cooled, and then heated from room temperature at a temperature rising rate of 20 ° C./min to obtain a temperature rising DSC curve. The melting temperature and the heating crystallization temperature were determined in accordance with JIS K-7121. The crystal melting energy was determined by first determining the area of the crystal melting endothermic peak, and based on the area of the indium melting endothermic peak under the same DSC measurement conditions. (2) Glass transition temperature A robot DSC "RDSC220" manufactured by Seiko Denshi Kogyo Co., Ltd. was used as a differential scanning calorimeter (DSC), and a disk station "S" manufactured by the company was used as a data analyzer.
SC / 5200 "on an aluminum pan
g of composition or film sample. This sample was once melted and rapidly cooled, and then heated from room temperature at a temperature rising rate of 20 ° C./min to obtain a temperature rising DSC curve. The glass transition temperature was determined according to JIS K-7121. (3) Melt viscosity Using a high-low flow tester, 280 ° C, shear rate 1
The value at 000 sec-1 is measured. The unit is [Pa
s]. (4) Heat Shrinkage (%) The heat shrinkage in the longitudinal direction and width direction of the film was measured according to the method specified in JIS C-2318. The sampling method was the same as for the sample of the elastic modulus. A sample having a sample width of 10 mm and a sample length of 200 mm was heat-treated in a gear oven under two conditions of 65 ° C., 60 minutes, 100 ° C., and 30 minutes, and the heat shrinkage was calculated from the change in sample length by the following equation.

Heat shrinkage (%) = [(length before heat treatment−length after heat treatment) / length before heat treatment] × 100 (5) Intrinsic viscosity 0.1 g at 25 ° C. in orthochlorophenol. / Ml
It is a measured value in concentration. The unit is represented by dl / g. (6) Average Fiber Diameter The average fiber diameter was determined by taking 10 photographs of the porous support at arbitrary 10 points at a magnification of 2000 times using an electron microscope, and arbitrarily selecting 15 fibers for each photograph. Is measured for 10 photographs, the diameter of a total of 150 fibers is measured, and the average value is shown. (7) Weight per unit area The polyester film was carefully peeled off from the heat-sensitive stencil sheet, and the porous support was cut into 20 x 20 cm.
It is a value obtained by measuring the weight and converting it to the weight per square meter. (8) Evaluation of curling properties A 10 cm square of heat-sensitive stencil printing paper was cut and left at 50 ° C. for 30 minutes, and then the curling state when the film layer was placed on a flat plate was observed and evaluated according to the following criteria. did.

[0060] A sample which maintained a flat surface without curling at all was marked with "◎". A slight lift at the end portion, but a sample with a lift height of 1 cm or less was marked with "○". Is more than 1 cm and less than 3 cm, "△" is more than 3 cm at the end, "x"
And ◎ and ○ are practically usable. (9) Evaluation of cutability The base paper for heat-sensitive stencil printing was RISOG manufactured by Riso Kagaku Corporation.
No. RAPH "GR375". An 8 chart (manufactured by Riso Kagaku Co., Ltd.) was used as a manuscript for plate making, and the plate was printed on a drum. This operation was performed 50 times, and the cutting state of the end of the base paper was visually observed, and the following judgment was made. Here, the cutting failure means that tears and wrinkles occur at the end of the base paper.

[0061] A sample that was cut normally 50 times was indicated by "O". A sample in which cut failure occurred 50 times was performed once.
And "△" and above are practical levels. (10) Evaluation of stencil release property Rigid paper for heat-sensitive stencil printing was manufactured by RISOG Co., Ltd.
No. RAPH "GR375". After making a plate using 8 charts (manufactured by Riso Kagaku Kogyo KK) as a manuscript and printing 100 sheets at a standard speed, the master was discharged. This operation was performed 50 times, and the following judgment was made.

[0062] The ones in which the plate discharging was performed normally 50 times are indicated by "O". The ones in which the plate discharging trouble occurred 50 times in the middle.
“×” was assigned. "△" and above are practical levels. (11) Evaluation of image quality The base paper for thermal stencil printing was RISOG manufactured by Riso Kagaku Corporation.
The ink was supplied to RAPH "GR375", and energy was applied to the thermal head by a thermal head type plate making method so that the porosity of the film became 35%, and all solid plate making printing was performed. And about the image of the 100th printed matter,
The white solid defect of the solid black portion was visually observed and determined as follows. Here, the white spot defect indicates a white spot having an area of 0.25 mm ² or more.

When no white spot defect was generated, “未 満”: less than 5 white spot defects, “○”: 5 to 10 white spot defects, “△”: white spot defect Are more than 10 were marked as "x".
"△" and above are practical levels.

[0064]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Example 1 A copolyester resin composed of 70 mol% of polyethylene terephthalate and 30 mol% of polyethylene isophthalate was treated in boiling water for 3 hours to crystallize the surface, and then dried under vacuum at 125 ° C. overnight. Thereafter, the copolymerized polyester resin and Ultem were mixed at a ratio of 9: 1,
Dry in a vacuum dryer at 140 ° C. for 3 hours or more. Thereafter, the mixture is put into an extruder, melt-extruded at 320 ° C., passed through a fiber sintered stainless steel filter, discharged at a draft ratio of 5 from a T-die into a sheet, and the sheet is subjected to a surface temperature of 25%. A non-oriented polyester film is obtained by bringing it into close contact with a cooling drum at ℃ and rapidly cooling and solidifying it.

Next, this non-oriented film was heated at 100 ° C.
The film is stretched 3.6 times and cooled with a cooling roll group at 50 ° C.
Next, this film was gripped with a clip and led to a first tenter, and stretched 3.7 times at 110 ° C.
Leading to a temperature zone of 110 ° C., followed by cooling to room temperature,
The film edge was removed to obtain a heat-sensitive stencil film having a thickness of 2 μm. Next, the resulting film was bonded to 100% natural fiber made of manila hemp using vinyl acetate as an adhesive and Japanese paper having a fiber weight of 10 g / m ² to prepare a heat-sensitive stencil sheet. Table 1 shows the thermal shrinkage of the film and the results of thermal characteristics. Table 2 shows the results of printing using the base paper. Example 2 A film was formed in the same manner as in Example 1 except that the copolymerized polyester resin used in Example 1 and Ultem were mixed at a ratio of 8: 2, and a heat-sensitive stencil sheet was prepared and printed. Tables 1 and 2 show the evaluation results of the film and the base paper. Example 3 A heat-sensitive stencil sheet was prepared in the same manner as in Example 1, except that a copolymerized polyester resin composed of 50 mol% of polyethylene terephthalate, 30 mol% of polyethylene naphthalate, and 20 mol% of polyethylene isophthalate was used. Printing. Tables 1 and 2 show the evaluation results of the film and the base paper. Comparative Example 1 Example 1 except that no polyetherimide was used.
A heat-sensitive stencil sheet was prepared and printed in the same manner as described above. Tables 1 and 2 show the evaluation results of the film and the base paper. Comparative Example 2 Example 3 except that no polyetherimide was used.
A heat-sensitive stencil sheet was prepared and printed in the same manner as described above. Tables 1 and 2 show the evaluation results of the film and the base paper.

From these results, the heat-sensitive stencil sheet prepared using the film of the present invention has curl properties, image properties,
It can be seen that this is a high-quality heat-sensitive stencil printing sheet excellent in cutting properties and plate discharging properties.

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[Table 1]

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[Table 2]

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According to the present invention, there is provided a heat-sensitive stencil film comprising two or more kinds of thermoplastic resins according to the present invention, wherein at least one kind is a polyetherimide.
Good thermal properties, curl properties of heat-sensitive stencil printing base paper,
It is a film that significantly improves imageability and plate dischargeability, and has extremely high industrial value.

Claims (6)

[Claims] 1. A heat-sensitive stencil film for stencil printing, comprising two or more thermoplastic resins, at least one of which is a polyetherimide. 2. The film for heat-sensitive stencil printing paper according to claim 1, wherein the film comprises two or more kinds of thermoplastic resins, and at least one kind is polyester. 3. The film for heat-sensitive stencil printing paper according to claim 1, wherein the polyetherimide is contained in an amount of 0.1 to 50% by weight. 4. The film has a crystal melting energy of 5 to 45.
The film for heat-sensitive stencil printing base paper according to any one of claims 1 to 3, which is J / g. 5. A film having a longitudinal direction (longitudinal direction) of 65 ° C.
The heat-sensitive stencil film for stencil printing according to any one of claims 1 to 4, wherein a heat shrinkage for 60 minutes is 1.5% or less. 6. A film in a longitudinal direction (longitudinal direction) of 100.
The film for heat-sensitive stencil printing paper according to any one of claims 1 to 5, wherein the heat shrinkage at 30 ° C for 30 minutes is 8% or more.