JP2000177264A - Base sheet for thermosensitive stencil printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance sensitivity, to obtain good printed image and to enhance conveyability in a printer by setting tensile elastic moduli of a thermoplastic resin film and a porous support so as to satisfy specific formulae in a base sheet for thermosensitive stencil printing having the film and the support. SOLUTION: A thermosensitive resin film and a porous support for forming a base sheet for thermosensitive stencil printing to be perforated and engraved by a thermal head or the like are formed to satisfy 1.10<=F(TD)/F(MD)<=2.50 and 0.30<=S(TD)/S(MD)<=0.90, wherein the F(TD) is a tensile elastic modulus of the film in a width direction, the F(MD) is a tensile elastic modulus of the film in a length direction, the S(D) is a tensile elastic modulus of the support in the width direction and the S(MD) is a tensile elastic modulus of the support in the length direction. As the resin, a polyester and its copolymer or blended material are preferable.

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 perforated by a thermal head or the like, and more particularly, to a heat-sensitive stencil sheet capable of smoothly performing stencil printing and obtaining a high quality printed image. Related to base paper for printing.

[0002]

2. Description of the Related Art Conventionally, as heat-sensitive stencil base paper (hereinafter simply referred to as "base paper"), thermoplastic fibers such as polyester films and vinylidene chloride films, natural fibers, chemical fibers or synthetic fibers or these fibers are used. Are known in which a porous support composed of thin paper, non-woven fabric, gauze, etc., which is mixed with, is bonded with an adhesive (for example, JP-A-51-2513, JP-A-57-182495). Issue publication).

In these base papers, a thermoplastic resin film is perforated by a thermal head or pulsed irradiation with a laser beam or the like, and further by flash irradiation or infrared irradiation with a halogen lamp, a xenon lamp, a flash lamp, or the like. Has an ink passage function. The plate making method using a thermal head is a method in which an original is read by an image sensor, converted into a digital signal, and an image corresponding to the original is perforated in a dot shape on a film portion of the base paper by the thermal head to perform plate making.

In such a plate making method using a thermal head, a film used as a base paper must be perforated with predetermined energy without fail, that is, perforated to an appropriate size so that an image at the time of printing becomes clear. It is desired to do.

For this reason, a film in which the ratio of the length direction to the width direction of the heat shrinkage stress is in a specific range has been proposed (for example, JP-A-5-116215, JP-A-7-16).
No. 4778).

[0006] Many improvements in stencil paper are made on both sides of the film and the porous support. However, in order to continuously and smoothly make a large number of stencil paper, the stencil paper must be transported by a stencil machine. Has a significant effect. The transportability of the base paper largely depends on the porous support. Therefore, a number of improvements of porous supports in base paper have been proposed. For example, a porous support has been proposed in which the ratio between the length direction and the width direction of the tensile stress is in a specific range (for example, JP-A-60-38193, JP-A-4-91994).

[0007] However, the films described in JP-A-51-2513 and JP-A-57-182495 are insufficient in sensitivity.

Further, Japanese Patent Application Laid-Open No. 5-1 for improving sensitivity.
In the base paper using the film described in Japanese Patent Application Laid-Open No. 16215 and Japanese Patent Application Laid-Open No. Hei 7-164778, although the sensitivity is improved, there is a problem that a trouble is easily caused at the time of plate making and printing in a printing press.

Further, JP-A-60-38193 and JP-A-4-91994 for the purpose of improving the transportability of base paper.
In the base paper described in Japanese Patent Application Laid-Open Publication No. H10-209, although the transportability is improved, there is a problem in that the sensitivity is lowered and a printed image is defective.

That is, there has been a demand for a heat-sensitive stencil sheet which can improve the sensitivity and obtain a good printed image, and has good transportability in a printing machine and can smoothly perform plate making and printing.

[0011]

SUMMARY OF THE INVENTION According to the present invention, the sensitivity, which cannot be obtained with the conventional base paper, can be improved and a good printed image can be obtained. It is an object of the present invention to provide a heat-sensitive stencil base paper that can be used in a stencil printing machine.

[0012]

Means for Solving the Problems The present inventors have conducted intensive studies in view of the above problems, and as a result, have found that the above problems can be solved by combining a specific thermoplastic resin film and a porous support. Invented the invention.

That is, the present invention provides a heat-sensitive stencil printing paper comprising a thermoplastic resin film and a porous support, wherein the thermoplastic resin film and the porous support have the following tensile elastic moduli (1) and (1). 2) A heat-sensitive stencil sheet which satisfies the expression 2).

1.10 ≦ F (TD) / F (MD) ≦ 2.50 (1) 0.30 ≦ S (TD) / S (MD) ≦ 0.90 (2) ( Where F (TD) is the tensile modulus in the width direction of the thermoplastic resin film, F (MD) is the tensile modulus in the length direction of the thermoplastic resin film, and S (TD) is the tensile modulus in the width direction of the porous support. Tensile modulus, S (MD) is the tensile modulus in the length direction of the porous support.)

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the heat-sensitive stencil sheet is a perforated plate made by a thermal head, a laser beam, a halogen lamp, a xenon lamp, a flash lamp or the like.

The thermoplastic resin constituting the film of the present invention includes polyester, polyamide, polyethylene,
Polypropylene, their respective copolymers, and blends thereof are preferred, but polyesters and their copolymers or blends are preferred. As the polyester, a polyester containing a dicarboxylic acid component and a glycol component as main components is preferable, and the dicarboxylic acid is an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid, or an alicyclic dicarboxylic acid. Here, as the aromatic dicarboxylic acid, for example, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,1,
5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,
Examples thereof include 4'-diphenyl ether dicarboxylic acid and 4,4'-diphenyl sulfone dicarboxylic acid. Examples of the aliphatic dicarboxylic acid component include succinic acid, adipic acid, suberic acid, sebacic acid, dodecandionic acid, eicosandioic acid, and dimer acid. Examples of the alicyclic dicarboxylic acid component include 1,4-cyclohexanedicarboxylic acid. One of these acid components may be used alone, or two or more thereof may be used in combination. Further, an oxyacid such as hydroxybenzoic acid may be partially copolymerized. Further, as the glycol 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- Examples thereof include cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, and 2,2-bis (4-hydroxyethoxyphenyl) propane.

In the present invention, the tensile modulus of the thermoplastic resin film needs to satisfy the following equation (1). 1.10 ≦ F (TD) / F (MD) ≦ 2.50 (1) (where F (TD) is the tensile modulus in the width direction of the thermoplastic resin film, and F (MD) is the thermoplastic) It is a tensile modulus in the length direction of the resin film.) A preferable range of F (TD) / F (MD) is a range represented by the following equation (4). 1.10 ≦ F (TD) / F (MD) ≦ 2.00 (4) If F (TD) / F (MD) is less than 1.10, the perforation sensitivity decreases, and It is not preferable because it causes blurring. Further, even if F (TD) / F (MD) exceeds 2.50, it is not preferable because the perforation sensitivity is lowered and the printed image is blurred.

The tensile modulus of the film according to the present invention is preferably at least 0.030 N / mm in both the length and width directions, and more preferably at least 0.040 N / mm. When the tensile elastic modulus in the length direction and the width direction of the film are both 0.030 N / mm or more, perforation due to cut of the film portion when printing is repeated does not occur.

The film of the present invention may be an unstretched film, but is preferably stretched, more preferably biaxially stretched.

The thickness of the film of the present invention is preferably 0.1.
1 to 7 μm, more preferably 0.2 to 5 μm,
Particularly preferably, it is 0.3 to 3 μm.

[0021] The porous support of the present invention is not particularly limited, but natural fiber paper, synthetic fiber paper, natural paper and paper made of a mixture of natural fibers and synthetic fibers, which are not substantially changed by heating in plate-making, thermoplastic, Various woven fabrics and nonwoven fabrics made of resin fibers can be used.

As an example of the non-woven fabric made of thermoplastic resin fibers, there is a non-woven fabric made of polyester fibers.
Specific examples of the polyester used for the nonwoven fabric are the same as the polyester constituting the above-mentioned film. More preferred are polyethylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexane dimethylene terephthalate, and a copolymer of ethylene terephthalate and ethylene isophthalate. Particularly preferred are polyethylene terephthalate and polyethylene-2,6-naphthalate from the viewpoint of thermal dimensional stability during perforation.

In the present invention, the tensile elastic modulus of the porous support must satisfy the following expression (2). 0.30 ≦ S (TD) / S (MD) ≦ 0.90 (2) (where S (TD) is the tensile modulus in the width direction of the porous support, and S (MD) is the porous modulus. It is a tensile modulus in the length direction of the support.) Further, a preferable range of S (TD) / S (MD) is a range represented by the following formula (5). 0.40 ≦ S (TD) / S (MD) ≦ 0.90 (5) Here, when S (TD) / S (MD) exceeds 0.90, the transportability in the printing press becomes poor. It is not preferable because it becomes worse and wrinkles or breaks during continuous plate making. Also,
When S (TD) / S (MD) is less than 0.30, it is not preferable because many wrinkles parallel to the length direction are easily formed.

The tensile elastic modulus of the porous support of the present invention is preferably 0.050 N / mm or more in both the length direction and the width direction, and more preferably 0.070 N / mm or more. When the tensile elastic modulus in both the length direction and the width direction of the porous support is 0.050 N / mm or more, the dimensional change when printing is repeated becomes small.

The basis weight of the porous support is not particularly limited, but is preferably ^{2 to 20} g / m ² , more preferably
5 to 15 g / m ² .

The fiber diameter of the fibers constituting the porous support is preferably 1 to 30 μm in the case of papermaking or nonwoven fabric, and 5 to 100 μm in the case of a mesh sheet.

In the base paper for heat-sensitive stencil printing of the present invention, the thermoplastic resin film and the porous support are bonded to each other via an adhesive such as a vinyl acetate resin, an acrylic resin, a urethane resin or a polyester resin. It may be good, but it may not be through an adhesive which is achieved by heat fusion or laminating and co-stretching a thermoplastic resin film and a non-woven fabric described later.

The base paper for heat-sensitive stencil printing of the present invention comprises a silicone oil, a silicone-based resin,
It is preferable to provide a thin layer comprising a fluororesin, a surfactant, an antistatic agent, a heat-resistant agent, an antioxidant, organic particles, inorganic particles, a pigment, a dispersing agent, a preservative, an antifoaming agent and the like.

The thickness of the thin layer for preventing fusion is preferably 0.005 μm or more and 0.4 μm or less, more preferably 0.01 μm or more and 0.3 μm or less.

In the base paper for heat-sensitive stencil printing of the present invention, it is preferable that the tensile elastic modulus of the base paper satisfies the following expression (3), since wrinkling when a large number of sheets are repeatedly printed is particularly small.

0.50 ≦ M (TD) / M (MD) ≦ 0.95 (3) (where M (TD) is the tensile modulus in the width direction of the base paper, M
(MD) is the tensile modulus in the longitudinal direction of the base paper. A more preferable range of M (TD) / M (MD) is a range represented by the following formula (6). 0.60 ≦ S (TD) / S (MD) ≦ 0.90 (6) The tensile elastic modulus of the heat-sensitive stencil sheet of the present invention is 0.120 N / mm or more in both the length and width directions. And more preferably 0.150 N / mm or more. When the tensile elastic modulus in the length direction and the width direction of the base paper are both 0.120 N / mm or more, there is almost no change in dimensional accuracy when printing is repeated.

Next, the method for producing the heat-sensitive stencil sheet of the present invention will be described.

[0033] The thermoplastic resin according to the present invention is obtained by a usual method. For example, in the case of polyester, it can be produced by the following method.

For example, a method in which a dicarboxylic acid component is subjected to a direct esterification reaction with a glycol component, and a product produced by heating the product of the reaction under reduced pressure to conduct polycondensation while removing an excess glycol component, There is a method in which a dialkyl ester is used as an acid component, a transesterification reaction is performed between the dialkyl ester and a glycol component, and then polycondensation is performed in the same manner as described above. At this time, if necessary, an alkali metal, an alkaline earth metal, manganese, cobalt, zinc, antimony, germanium, a titanium compound or the like can be used as a reaction catalyst. Further, a phosphorus compound can be used as a heat stabilizer.

The thermoplastic resin of the present invention may contain a flame retardant, an antioxidant, an ultraviolet absorber, a pigment, a dye,
An antifoaming agent such as polysiloxane can be blended.

Further, a commonly used method for imparting lubricity may be employed. For example, clay, mica,
A method of blending inorganic particles such as titanium oxide, calcium carbonate, kaolin, talc, wet or dry silica, alumina, zirconia, organic particles containing acrylic acid, styrene, etc., and a catalyst to be added during the polymerization reaction. And a method of applying or blending a lubricant such as a surfactant.

In the present invention, the method for biaxially stretching the film may be any of a sequential biaxial stretching method and a simultaneous biaxial stretching method. In the case of the sequential biaxial stretching method, for example, an unstretched film is obtained by extruding a thermoplastic resin onto a cast drum by a T-die extrusion method,
Next, the film is generally stretched in the order of the longitudinal direction and the transverse direction, but may be stretched in the opposite direction. The stretching temperature is preferably between the glass transition temperature of the polyester film and the elevated crystallization temperature. The stretching ratio is not particularly limited, and is appropriately determined depending on the type of the film polymer to be used, but is preferably 2 to 8 times, and more preferably 3 to 8 times, in each of the vertical and horizontal directions. After biaxial stretching, the film may be stretched longitudinally or horizontally, or vertically and horizontally again. After that, the film after biaxial stretching may be heat-treated. The heat treatment temperature is not particularly limited and is appropriately determined depending on the type of the film polymer to be used, but is usually 80 to 200 ° C, preferably 80 to 170 ° C, more preferably 90 to 150 ° C, and the time is 0.5. About 60 seconds is appropriate.

After the film obtained by the heat treatment is once cooled to about room temperature, it can be further aged at a relatively low temperature of 40 to 90 ° C. for about 5 seconds to 1 week.

In the present invention, any method may be used for satisfying the above-mentioned formula (1) for the tensile modulus of the thermoplastic resin film, but any combination of the type of the polymer used, the temperature at the time of stretching, and the magnification may be used. Can be achieved by

For example, in the case of polyester, the temperature and the magnification in the above-mentioned sequential biaxial stretching can be achieved by carrying out a high magnification at a high temperature in a longitudinal direction and a low magnification in a transverse direction.

The method of satisfying the above-mentioned formula (1) for the tensile elastic modulus of the porous support may be any method. For example, in the case of papermaking, papermaking such as the composition, temperature and speed of the fiber may be used. This can be achieved by adjusting the calendar such as conditions, temperature and pressure.

In the present invention, as a method for forming a heat-sensitive stencil sheet, a method may be used in which the thermoplastic resin film and the porous support are bonded together with an adhesive.
A method of bonding without using an adhesive may be used. Examples of the adhesive include a vinyl acetate resin, an acrylic resin, a urethane resin, and a polyester resin.

In particular, as a method of bonding without using an adhesive, there is also a method of heat-sealing a film and a porous support near the melting point of the film or the porous support.
When the film is biaxially stretched, a method in which unstretched porous supports are overlapped and co-stretched can be used. In order to perform biaxial stretching with such superposition, as the unstretched porous support, a woven fabric or a nonwoven fabric made of thermoplastic resin fibers is preferable, and a nonwoven fabric made of polyester fibers is particularly preferably used.

When a thin layer for preventing fusion is provided on the base paper 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 removed by drying or the like. The method is preferably used. The coating may be performed at any stage before or after the stretching of the film. In order to more remarkably exhibit the effects of the present invention, it is particularly preferable to apply the composition before stretching. 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, if necessary, the surface to be coated may be subjected to a corona discharge treatment in air or other various atmospheres.

[Method for Measuring Characteristics] (1) Tensile modulus A sample was cut in the longitudinal and width directions, and ten samples having a width of 2 cm and a length of 15 cm were collected, and “Tensilon” was obtained.
With a tensile tester (manufactured by Toyo Sokki), hold it at a test length of 5 cm,
Pull at a speed of 5 cm / min and record the load-elongation relationship. The elastic modulus was obtained from the initial linear portion of the load-elongation, and the average was represented by 10 samples in each direction.

(2) Sensitivity The produced base paper is supplied to a printing machine lithograph (GR275) manufactured by Riso Kagaku Kogyo Co., Ltd. The original plate was made by making a plate in the same shape. The energy supplied to the thermal head was 40 μJ per dot. Plate making is performed with the base paper, and the perforated part is scanned with a scanning electron microscope.
Observation was performed at a magnification of 0.

The sensitivity was determined by measuring the area of the perforated portion and converting the area per dot. Measurement is 150 per field
The measurement was performed for 10 visual fields, and the average value was obtained and evaluated according to the following criteria.

Those having an average value of 1400 × 10 ^-12 m ² or more are evaluated as ◎, and those having an average value of 1000 × 10 ^-12 m ² or ^more1
を means less than 400 × 10 ^-12 m ² , average value is 5
Those having a value of at least 00 × 10 ⁻¹² m ^{2 and} less than 1000 × 10 ⁻¹² m ² were rated as Δ, and those having an average value of less than 500 × 10 ⁻¹² m ² were rated as ×. In the evaluation, ◎, △, and Δ are practically used.

(3) Print Image Properties The prepared base paper is supplied to a printing machine lithograph (GR275) manufactured by Riso Kagaku Kogyo Co., Ltd. Plate making and printing were performed. The energy supplied to the thermal head was 40 μJ per dot. The printed matter was observed, and the print clarity was evaluated based on the following criteria.

も の indicates that the image was printed without any problem, and △ indicates that the ruled line was slightly thickened or blurred.
When the ruled line was thickened or distorted, or when the ruled line was interrupted and a discontinuous portion was generated, it was evaluated as x. In the evaluation, ◎, △, and Δ are practically used.

(4) Conveyability in a printing press The prepared base paper is supplied to a printing machine lithograph (GR275) manufactured by Riso Kagaku Kogyo Co., Ltd., and is subjected to plate making using a black solid original by a thermal head plate making method. Ten prints were made.

The plate making and printing operations were repeated 10 times continuously, and the evaluation was made according to the following criteria based on the frequency of troubles due to wrinkles of the stencil, occurrence of creases in the printing paper, and poor conveyance in the printing machine at that time.

When no trouble was found, ○ was given when trouble occurred once or twice, and when × was given 3 times or more. In the evaluation, ◎, △, and Δ are practically used.

[0055]

Example 1 [Production of thermoplastic resin film] 100 parts by weight of a raw material of a copolymerized polyester composed of 85 mol% of ethylene terephthalate and 15 mol% of ethylene isophthalate and 0.4 weight of silica particles having an average particle diameter of 1.2 μm Were melt-kneaded using a twin-screw extruder and extruded and cut to obtain a particle-containing copolymerized polyester raw material.

The obtained copolymer polyester material containing particles was vacuum-dried at 150 ° C. for 5 hours using a rotary dryer. The obtained polymer was supplied to an extruder, melted at 270 ° C., extruded from a T-type die into a sheet shape on a drum, and cooled and solidified to obtain an unstretched film.

Then, the unstretched film was heated to 90 ° C. using a sequential biaxial stretching machine and stretched 3.0 times in the longitudinal direction.
After further heating to 85 ° C. and stretching 4.5 times in the width direction, 12
Heat treatment was performed at 0 ° C. for 5 seconds, followed by cooling to obtain a biaxially stretched film having a thickness of 1.5 μm.

[Production of Porous Support] A polyethylene terephthalate chip was melted at 290 ° C., discharged at 285 ° C. through a die having 900 holes, and wound up at a speed of 1000 m / min. Next, this undrawn yarn is treated at a magnification of 3.8 times at 8 times.
It was stretched in warm water at 0 ° C., subjected to a tension heat treatment at 200 ° C., and further subjected to a relaxation heat treatment at 125 ° C., and then cut into 5 mm to obtain a main fiber having an average fiber diameter of 5 μm and a birefringence of 0.20.

On the other hand, a polyethylene terephthalate chip was melted at 290 ° C.
The mixture was discharged at 5 ° C. and cut into 5 mm pieces to obtain undrawn fibers having an average fiber diameter of 8 μm and a birefringence of 0.05.

After the main fiber and the undrawn fiber were sufficiently mixed and dispersed in a pulper at a weight ratio of 80:20, the yarn was dried at a speed of 9 m / min.
It was dried by heating at 0 ° C. The weight per unit area was 10 g / m ² .

Next, the metal roll surface temperature was 210 ° C. and the linear pressure was 12 kg / cm using a metal / elastic roll calendering machine.
Under the following conditions to obtain a nonwoven fabric having a thickness of 40 μm.

[Production of base paper] The porous support was bonded to the biaxially stretched film having a thickness of 1.5 μm using a vinyl acetate-based adhesive, and a silicone release film was attached to the surface of the film opposite to the nonwoven fabric side. A base material was obtained by applying a template.

[Evaluation] The properties of the base paper were evaluated and are shown in Table 1. ADVANTAGE OF THE INVENTION The base paper of this invention improves a sensitivity and can obtain a favorable printed image, and also has good transportability in a printing machine and can perform plate making and printing smoothly.

Comparative Example 1 [Production of thermoplastic resin film] Using the unstretched film obtained in Example 1, a film was formed.

Using a sequential biaxial stretching machine, the unstretched film was heated to 90 ° C. and stretched 3.8 times in the longitudinal direction.
After heating to 0 ° C and stretching 3.8 times in the width direction, 5 ° C at 120 ° C
After a heat treatment for 2 seconds, the film was cooled to obtain a biaxially stretched film having a thickness of 1.5 μm.

[Production of porous support] As in Example 1, the main fiber and the unstretched fiber were sufficiently mixed and dispersed in a pulper at a weight ratio of 80:20, and then the mixture was fed at a speed of 7 using a circular paper machine.
Heat drying was performed at a surface temperature of 120 ° C. at a m / min. The weight per unit area was 10 g / m ² .

Next, the metal roll surface temperature was 200 ° C. and the linear pressure was 15 kg / c using a metal / elastic roll calendering machine.
By pressing under a condition of m, a nonwoven fabric having a thickness of 35 μm was obtained.

[Production of base paper] The porous support was bonded to the above-mentioned biaxially stretched film having a thickness of 1.5 μm using a vinyl acetate-based adhesive, and a silicone release film was attached to the opposite side of the nonwoven fabric side of the film. A base material was obtained by applying a template.

[Evaluation] Table 1 shows the characteristics of the base paper. The obtained base paper had poor transportability in a printing machine and a poor printed image.

Examples 2 to 6, Comparative Examples 2 to 4 Base papers were prepared in the same manner as in Example 1 except that the films and the porous supports shown in Table 1 were used.

[Evaluation] Table 1 is obtained by evaluating the characteristics of the base paper.
It was shown to. ADVANTAGE OF THE INVENTION The base paper of this invention improves a sensitivity and can obtain a favorable printed image, and also has good transportability in a printing machine and can perform plate making and printing smoothly.

Example 7 Fabrication of Unstretched Polyester Nonwoven Fabric 0.35 m pore size
m, using a rectangular spinneret having 100 holes and a spinneret temperature of 2
A polyethylene terephthalate raw material (melting point: 257 ° C., intrinsic viscosity: 0.50) was spun at 90 ° C. at a discharge rate of 30 g / min by a melt blow method, and the fibers were collected and wound on a net conveyor at a collection distance of 13 cm. . At this time, the amount of hot air blown from around the base was set to 2.4 Nm ³ / min, and the temperature of the web immediately below the base was set to 95 ° C. by a suction device provided on a net conveyor. The fiber weight of the unstretched nonwoven fabric is 110 g /
m ² , and the average fiber diameter was 9.8 μm.

[Film Forming] The particle-containing copolymerized polyester raw material obtained in Example 1 was heated at 150 ° C. using a rotary dryer.
For 5 hours under vacuum. The obtained polymer was supplied to an extruder, melted at 270 ° C., extruded from a T-type die into a sheet shape on a drum, and cooled and solidified to obtain an unstretched film.

The unstretched nonwoven fabric was placed on the unstretched film, and nips were applied to a roll heated to 80 ° C. at a pressure of 1 kg / cm, and heated to 90 ° C. to increase the length by 4.0 times in the longitudinal direction.
A silicone release agent was applied to the surface of the film opposite to the nonwoven fabric surface using a bar coater, stretched 3.0 times at 90 ° C. in the width direction, and heat-treated at 120 ° C. to obtain a base paper.

[Evaluation] Since the obtained base paper had a film portion and a non-woven fabric portion integrated, the characteristics of the film and the non-woven fabric alone were evaluated using a sample from which the non-woven fabric portion or the film portion was sufficiently removed from the base paper. . The results are shown in Table 1.

The base paper of the present invention has improved sensitivity and can obtain a good printed image, and has good transportability in a printing machine and can smoothly perform plate making and printing.

[0077]

[Table 1]

[0078]

As described above, the heat-sensitive stencil sheet of the present invention has improved sensitivity and can obtain a good printed image, and has good transportability in a printing machine, so that plate making and printing can be smoothly performed. It can be carried out.

Claims (2)

[Claims] 1. A heat-sensitive stencil printing paper comprising a thermoplastic resin film and a porous support, wherein the thermoplastic resin film and the porous support have the following tensile modulus.
And a heat-sensitive stencil sheet which satisfies the formula (2). 1.10 ≦ F (TD) / F (MD) ≦ 2.50 (1) 0.30 ≦ S (TD) / S (MD) ≦ 0.90 (2) (where F (TD): Tensile modulus in the width direction of the thermoplastic resin film, F (MD): Tensile modulus in the length direction of the thermoplastic resin film, S (TD): Tensile modulus in the width direction of the porous support , S (MD): tensile modulus in the longitudinal direction of the porous support
) 2. The heat-sensitive stencil printing paper according to claim 1, wherein the tensile elastic modulus of the base paper satisfies the following expression (3). 0.50 ≦ M (TD) / M (MD) ≦ 0.95 (3) (where M (TD) is the tensile modulus in the width direction of the base paper, and M (MD) is the length direction of the base paper. Tensile modulus of)