JPH10119448A - Base paper for thermal stencil printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make durability excellent by joining a polyester film and polyester nonwoven fabric without using an adhesive as an intermediary and by setting a tear propagation resistance in the longitudinal direction to be in a specified range. SOLUTION: Polyester is prepared by putting an acid component in an esterification reaction directly with a diol component and by subjecting a product of this reaction to condensation polymerization by heating it under a reduced pressure, while removing an excess of the diol component. A polyester film is obtained by extruding this polyester onto a cast drum by a T-die extrusion method. The polyester film thus obtained and polyester nonwoven fabric are joined by a method of thermocompression bonding and, besides, a tear propagation resistance in the longitudinal direction is set to be 1-8 N. According to this constitution, a property of perforation and easiness of cutting are made excellent and a printed matter is made fine and clear in a high degree.

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 which is perforated by pulsed irradiation with a thermal head or a laser beam or the like, and more particularly to a heat-sensitive stencil sheet having excellent durability during printing and excellent printability. It relates to a stencil printing paper.

[0002]

2. Description of the Related Art Thermosensitive stencil printing uses an ink-permeable porous support to which a thermoplastic resin film is attached as a base paper, converts an image of an original read by a sensor into a digital signal, and heats the image by a thermal head. The plastic resin film is heated and melted to perform perforation plate making, and the perforated portion is made to infiltrate the printing ink from the porous support side and printed on printing paper.

In recent years, heat-sensitive stencil printing machines have been improved to respond to the demands for high-definition printing and high-speed plate making, such as increasing the dot density of a thermal head and reducing plate making energy. Base paper is required. At the same time, there is a demand for a base paper having excellent printing durability, which does not deform or break the base paper when printing a large number of sheets.

[0004] Conventionally, as stencils for heat-sensitive stencil printing, acrylonitrile-based films, polyester-based films,
Known is a structure in which a porous support composed of thin paper, nonwoven fabric, gauze, or the like, made of natural fiber, chemical fiber, or synthetic fiber, or a mixture thereof, is bonded to a thermoplastic resin film such as a vinylidene chloride-based film with an adhesive. (See, for example, JP-A-51-2513,
182495. ).

However, in the conventional heat-sensitive stencil printing paper, white spots are generated in a black solid portion, fine characters are blurred, or the like.
Further, in printing a large number of sheets, there are drawbacks such as wrinkling of the base paper, separation of the film and the support, and breakage of the base paper. The causes of poor printability and poor printing durability of these conventional base papers are that the adhesion of the film and the porous support is hindered by the adhesion of the ink, or the moisture or the organic solvent in the ink causes the adhesion of the adhesive. May be eroded to lower the adhesive strength.

Various proposals have been made so far to improve the drawbacks of the conventional base paper. For example, Japanese Patent Application Laid-Open
JP-A-147396 and JP-A-4-232790 disclose a heat-sensitive stencil sheet in which the amount of adhesive used is as small as possible. There has been proposed a heat-sensitive stencil sheet obtained by spraying synthetic fibers on one surface of a plastic resin film and thermocompression bonding. However, in these methods, there is a problem in that the adhesive strength becomes insufficient, or when trying to obtain a sufficient adhesive strength, the orientation of the film is reduced, the perforation becomes insufficient, and it is difficult to make a plate making faithful to the original. I understand.

Further, Japanese Patent Application Laid-Open No. Hei 6-305273,
JP-A-7-186565 discloses that a base paper is obtained by heat-bonding an unstretched polyester film and polyester fiber and then co-stretching. Although the base paper has a sufficient adhesive strength between the film and the support fiber without using an adhesive, the performance is still insufficient in terms of high sensitivity and printing durability required in recent years. .

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a heat-sensitive stencil sheet having excellent high-definition printability and particularly excellent durability.

[0009]

According to the present invention, a polyester film and a polyester non-woven fabric are joined without using an adhesive, and the tear propagation resistance in the longitudinal direction is one.
８8N.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester used for the polyester film in the present invention is a polyester having an aromatic dicarboxylic acid or an aliphatic dicarboxylic acid and a diol as main components. Here, as the aromatic dicarboxylic acid, for example, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid,
4,4'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'-diphenylsulfonedicarboxylic acid and the like can be used. Of these, terephthalic acid and isophthalic acid are preferred. As the aliphatic dicarboxylic acid component, for example, adipic acid, suberic acid, sebacic acid, dodecanedioic acid and the like can be used. 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 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- Cyclohexane dimethanol, 1,3-cyclohexane dimethanol, 1,4-cyclohexane dimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2′bis (4′-β-hydroxyethoxyphenyl) propane, and the like. Can be. 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 in the polyester film of the present invention is, from the viewpoint of printability, a copolymer in which ethylene terephthalate, butylene terephthalate, and hexylene terephthalate are the main repeating units and other components are copolymerized, and a blend thereof. More preferred,
The copolymerization amount is particularly preferably 5 to 50 mol%. The polyester used in the polyester non-woven fabric of the present invention has an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid, or an alicyclic dicarboxylic acid and a diol as main components similarly to the film. Preferable examples include polyethylene terephthalate, polyethylene naphthalate, polycyclohexane dimethylene terephthalate, and a copolymer of ethylene terephthalate and ethylene isophthalate. Particularly preferred are polyethylene terephthalate and polyethylene naphthalate from the viewpoint of thermal dimensional stability during perforation.

The polyester according to the present invention can be produced by the following method. For example, a method in which an acid component is directly esterified with a diol component, and then the product of this reaction is heated under reduced pressure to remove the excess diol component and polycondensate to produce a dialkyl acid. There is a method of using an ester, performing a transesterification reaction between the ester and a diol component, and then performing polycondensation in the same manner as described above. At this time, if necessary,
As a reaction catalyst, an alkali metal, an alkaline earth metal, manganese, cobalt, zinc, antimony, germanium, or a titanium compound can also be used.

The polyester of the present invention may contain, if necessary, an organic lubricant such as a flame retardant, a heat stabilizer, an antioxidant, an ultraviolet absorber, an antistatic agent, a pigment, a fatty acid ester, a wax, or a polysiloxane. A foaming agent and the like can be blended. Furthermore, in order to impart lubricity, for example, clay, mica, titanium oxide, calcium carbonate,
A method of blending inorganic particles such as kaolin, talc, wet or dry silica, organic particles containing acrylic acid-based polymers, polystyrene, etc., and catalysts added during the polyester polymerization reaction are formed by deactivation. A method using so-called internal particles can also be used.

The melting point of the polyester film of the present invention is as follows:
From high definition printability, preferably 150 to 240 ° C., more preferably 160 to 230 ° C., and particularly preferably 170 to 2 ° C.
30 ° C.

[0015] The melting point of the polyester nonwoven fabric of the present invention is preferably higher than the melting point of the polyester film, more preferably 5 ° C or higher, particularly preferably 10 ° C or higher, from the viewpoint of thermal stability during perforation.

In the heat-sensitive stencil printing paper of the present invention, it is necessary that the polyester film and the polyester non-woven fabric are joined without using an adhesive. When the film and the porous support are adhered to each other with an adhesive, the adhesive may impede the permeation of the ink, or the adhesive in the ink may be eroded by water or an organic solvent in the ink, so that the adhesive strength may be reduced. This causes white spots on the black solid portion, blurred fine characters, and when printing a large number of sheets, wrinkles occur on the base paper, the film and the support are separated, and the base paper is broken. This is because there is a drawback in that

As described above, any method can be used to join the polyester film and the polyester non-woven fabric without the use of an adhesive, but in particular, the heat of directly bonding the unstretched polyester film and the unstretched polyester non-woven fabric while heating them is applied. The method of performing co-stretching after performing the pressure-bonding treatment is a particularly preferable method because strong adhesion can be achieved.

The base paper of the present invention is preferably obtained by directly bonding the unstretched polyester film and the unstretched polyester nonwoven fabric while heating, thermocompression bonding, and costretching.

In the present invention, the unstretched polyester nonwoven fabric is an unstretched nonwoven fabric having a low orientation obtained by a direct melt spinning method such as a melt blow method or a spun bond method using the above polyester. The intrinsic viscosity [η] of the polymer used is preferably at least 0.30, more preferably at least 0.40.

In the melt blow method, when the molten polyester polymer is discharged from a die, hot air is blown from a peripheral portion of the die, and the discharged polymer is made finer by the hot air. It is manufactured by spraying and collecting to form a web. Since the web is sucked together with the hot air by the suction device provided on the net conveyor, the fibers are collected before the fibers are completely solidified. That is, the fibers of the web are collected in a state where they are fused to each other. By appropriately setting the collection distance between the base and the net conveyor, the degree of fusion of the fibers can be adjusted. Further, by appropriately adjusting the amount of discharged polymer, the temperature of hot air, the flow rate of hot air, the moving speed of the conveyor, and the like, it is possible to arbitrarily set the basis weight of the web and the fineness of single yarn. The melt-blown fiber is fined by the pressure of hot air, but is not drawn,
It is solidified in a so-called non-oriented state. The thickness of the fibers is not uniform, and the web is formed in a state where the thick fibers and the fine fibers are appropriately dispersed. Further, the polymer discharged from the die is rapidly cooled from a molten state to a room temperature atmosphere, and thus solidifies in a state close to amorphous.

Similarly, in the spunbonding method, the polymer discharged from the die is pulled by an air ejector, and the obtained filaments collide with a collision plate to spread the fibers.
It is manufactured by collecting on a conveyor to form a web. By appropriately setting the polymer discharge amount and the conveyor speed, the fiber basis weight of the web can be arbitrarily set. In addition, by appropriately adjusting the pressure and the flow rate of the ejector, the molecular orientation state of the filament can be arbitrarily adjusted. By reducing the spinning speed by reducing the pressure and flow rate, a fiber web having a low degree of molecular orientation can be obtained. Further, by adjusting the cooling rate of the discharged polymer, a fiber web having a different crystallinity can be obtained.

For example, the crystallinity of the unstretched polyester nonwoven fabric preferably used in the present invention is preferably 20% or less, more preferably 15% or less, in order to sufficiently fuse with the film.
%, Particularly preferably 10% or less. On the other hand, the degree of orientation of the unstretched polyester nonwoven fabric is desirably low from the viewpoint of co-stretchability, and is preferably 0.03 or less, more preferably 0.01 or less.

In the present invention, a method for obtaining an unstretched film is based on the following method. For example, an unstretched film can be produced by extruding a polyester onto a cast drum by a T-die extrusion method. An unstretched film having a desired thickness can be produced by adjusting the slit width of the die, the discharge amount of the polymer, and the rotation speed of the cast drum.

The method of thermocompression bonding of the unstretched polyester film and the unstretched polyester nonwoven fabric in the present invention is not particularly limited, but thermocompression bonding with a heating roll is particularly preferred in view of easiness of the process. The thermocompression bonding in the present invention, after casting a polyester film,
It is preferable to perform it before the stretching step. Thermocompression bonding temperature is from 50 ℃ to glass transition point (Tg) of polyester non-woven fabric
Preferably between + 20 ° C.

Next, the unstretched polyester film and the unstretched polyester nonwoven fabric which are thermocompression-bonded are co-stretched. By co-stretching in the state of thermocompression bonding, the film and the support can be stretched integrally. In addition, by co-stretching both, the polyester nonwoven fabric functions as a reinforcing member, the film is not broken, and the film-forming stability is extremely excellent.

Biaxial stretching is preferred from the viewpoint of improving the perforation sensitivity of the film and the uniform dispersibility of the fibers forming the polyester nonwoven fabric. The biaxial stretching may be any of a sequential biaxial stretching method and 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 horizontal direction, but may be performed in the opposite direction. The stretching temperature is the glass transition temperature (Tg) of the polyester film and the cold crystallization temperature (Tc).
and c). The stretching ratio is not particularly limited, and is appropriately determined depending on the type of the polymer for the polyester film to be used, the sensitivity required for the base paper, and the like.
After biaxial stretching, the film may be stretched longitudinally or horizontally, or vertically and horizontally again.

Further, it is preferable that the base paper of the present invention after biaxial stretching is subjected to a heat treatment. The heat treatment is performed at a temperature of 50 ° C. or more and a melting point (Tm) of the polyester nonwoven fabric polymer for 0.5 to 60 seconds.

The tear propagation resistance in the longitudinal direction of the heat-sensitive stencil sheet of the present invention is 1 to 8 N from the viewpoint of transportability and durability.
Preferably it is 1.5-5N. If the tear propagation resistance in the longitudinal direction is less than 1 N, the base paper is liable to be damaged at the time of mass printing and the printing durability becomes poor, which is not preferable. On the other hand, if it exceeds 8N, it is not preferable because the base paper cannot be cut at the time of transport and plate making.

Any method can be used to adjust the tear propagation resistance in the longitudinal direction of the base paper of the present invention to the above-mentioned range. Particularly, in the step of co-stretching the polyester film and the polyester nonwoven fabric in the longitudinal direction, a silicone rubber roll is preferably used. Using a soft roll such as a soft roll, and also using a soft roll such as a silicone rubber roll as a pressure roll on the stretching roll, at a pressure of 1.0 to 4.0 N / cm and lower than the preheating temperature of the polyester nonwoven fabric. This is most preferably achieved by co-stretching at a temperature.

The thickness of the polyester film of the present invention is as follows:
0.1 to 5 μm, more preferably 0.1 to 3 μm, particularly preferably 0.1 to 2 μm from the viewpoint of high-definition printability
This is a biaxially stretched film.

The crystal melting energy of the polyester film of the present invention is preferably 2 to 2 from the viewpoint of high definition printability.
It is 45 J / g, more preferably 2 to 35 J / g.

The orientation parameter of the polyester film of the present invention is preferably 1 × 10 ^{−2 to} 9 × 1 from the viewpoint of printability.
0 ⁻¹ , more preferably 1 × 10 ^{−2 to} 5 × 10 ⁻¹ .

Here, the orientation parameter is defined as Jobin Yv
on / Raman Raman method using Ramanor T-64000 manufactured by Atago Bussan. 1615c in the plane direction of the film
The ratio (I) between the peak intensity (I) of the m ^-1 band and the peak intensity (I _ND ) of the 1615 cm ^-1 band in the thickness direction of the film.
/ I _ND ) was determined from the following equation.

Orientation parameter = 275 × (I / I _ND −
1) / (I / I _ND +2) The fiber diameter of the polyester nonwoven fabric of the present invention is preferably 3 to 30 μm, more preferably 3 to 10 μm from the viewpoint of strength and transportability.
m of oriented fiber.

The basis weight of the fiber is preferably ^{2 to 20} g / m ² , more preferably 5 to 20 g / m ² from the viewpoint of strength and transportability.
It is.

The crystal melting energy (ΔHu) of the polyester nonwoven fabric of the present invention is preferably from 20 to 65 J / g, more preferably from 30 to 6 from the viewpoint of heat resistance and durability.
5 J / g.

The crystallinity of the fibers constituting the polyester nonwoven fabric of the present invention is preferably at least 20%, more preferably at least 30%, from the viewpoint of heat resistance.

When the polyester nonwoven fabric of the present invention is observed two-dimensionally, the area fraction of the openings forming the network is preferably 5 to 80%, more preferably 5 to 50%, from the viewpoint of the permeability of the printing ink. It is. When the opening formed by the net is regarded as a circle, the average value of the equivalent circular diameter is preferably 5 to 100 μm from the viewpoint of ink permeability and retention.
m, more preferably 10 to 60 μm, particularly preferably 1 to 60 μm.
0 to 30 μm. The fibers constituting the polyester nonwoven fabric of the present invention may all have the same fiber diameter, or may be a mixture of fibers having different fiber diameters. Also,
It may be a multilayer structure in which fibers having different fiber diameters are laminated stepwise. In the case of a multilayer structure, at least the layer facing the film is composed of fibers of 10 μm or less, and the remaining layers are 10 μm or less.
The use of the above fibers is more preferable in terms of balance between image clarity and support strength. Here, the fiber diameter is defined as an arbitrary value of 10 points of the polyester non-woven fabric, which was observed at a magnification of 2 with an electron microscope.
Ten photographs were taken at a magnification of 000, the diameter of any fifteen fibers was measured for each photograph, and this was performed for ten photographs, and the fiber diameter of a total of 150 fibers was measured. It is represented by a value.

In the case of a multilayer structure, the fiber weight of the layer facing the film is preferably 1 to 5 g / m ² .

Here, the basis weight of the fiber means that the porous support is 2
Cut to 0 cm x 20 cm, weigh it and measure m ²
It is a value converted to the weight per unit.

The base paper of the present invention is used to prevent fusing at the time of perforation on one side of the film to be in contact with the thermal head.
Silicone oil, silicone resin, fluorine resin,
It is preferable to provide a thin layer comprising 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, it is 0.01 μm or more and 0.4 μm or less.

When a thin layer for preventing fusion is provided on the base paper of the present invention, it is preferable to apply the coating solution in the form of a coating solution dissolved, emulsified or suspended in water, and then remove the water by drying or the like. . The coating may be performed at any stage before or after the stretching of the film. In order to achieve the effect of the present invention more remarkably, it is particularly preferable to apply before horizontal stretching in the case of sequential biaxial stretching in which horizontal stretching is performed after longitudinal stretching, and before stretching in the case of simultaneous biaxial 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, an activation treatment such as a corona discharge treatment may be applied to the coated surface in air or other various atmospheres.

[Method of measuring properties] (1) Tear propagation resistance Light weight Tearing Te manufactured by Toyo Seiki Seisaku-sho, Ltd.
Using a ster (light load tearing tester) No.485451-10, the base paper is cut into a size of 63.5 mm (longitudinal direction) × 50.8 mm (horizontal direction), and is further directed to the center in the horizontal direction in the longitudinal direction. A 12.7 mm cut was made for the measurement.

(2) Melting point Differential scanning calorimeter RDC220 manufactured by Seiko Electronic Industry Co., Ltd.
Using a mold, 5 mg of a polyester film and polyester nonwoven fabric sample peeled from the base paper were sampled, and the peak of an endothermic curve when the temperature was raised from room temperature at a rate of temperature rise of 20 ° C./min was determined and defined as a melting point. (3) Crystal melting energy (ΔHu) of polyester film and polyester nonwoven fabric Differential scanning calorimeter RDC220 manufactured by Seiko Electronics Industry Co., Ltd.
Using a mold, it is determined from the area of the film and the nonwoven fabric at the time of melting. This area is shifted from the baseline to the absorption side by increasing the temperature, and is the area until the temperature returns to the baseline position when the temperature is further increased.The area from the melting start temperature position to the end position is connected by a straight line. (A) is obtained.
In (indium) is measured under the same DSC conditions, and the area (b) is determined as 28.5 J / g by the following equation.

ΔHu = 28.5 × a / b (J / g) (4) Intrinsic viscosity [η] After the sample was dried at 105 ° C. for 20 minutes, 0.8 ± 0.00.
5 g is weighed, and 160 ° C. × 1 in o-chlorophenol.
Stir for 5 minutes to dissolve. After cooling, the viscosity at 25 ° C. was measured with a Yamatra Robotic AVM-10S automatic viscosity meter.

(5) Durability The prepared base paper was used as RISOGRAP manufactured by Riso Kagaku Corporation.
H "SR7200", and by a thermal head plate making method, JIS first level character size of 2 mm square, 5 mm square and ● (circle black inside) 2 to 10 mmφ Plates were made using originals and ruled lines with different thicknesses as originals. Printing was repeated using the plate-making manuscript, and the number of sheets until the base paper was damaged and the printed matter was stained was examined.

A over 3000 A up to 1000-3000 B (level that can be practically used somehow) up to 500-1000 C less than 500 D (6) Evaluation of printability The prepared base paper was prepared by RISOGRAP manufactured by Riso Kagaku Corporation.
H "SR7200", and by a thermal head plate making method, JIS first level character size of 2 mm square, 5 mm square and ● (circle black inside) 2 to 10 mmφ Plates were made using originals and ruled lines with different thicknesses as originals.

The printed matter using the plate-making manuscript was evaluated as follows by visual judgment.

When the character is clear, the ruled line has no thickness unevenness, and there are no white spots in the black solid area, the mark "○" indicates that the character is unclear, the ruled line is cut off, and the black solid area has white spots. ×
The mark, which is intermediate between ○ and ×, and which can be used practically in practical use, was marked with Δ.

[0050]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. .

Example 1 A hole diameter of 0.32 mm and the number of holes was 10
Using 0 rectangular spinnerets, a polyethylene terephthalate raw material ([η] = 0.485, Tm = 255 ° C) is spun out by melt-blowing at a die temperature of 290 ° C and a discharge rate of 35 g / min. The fibers were collected to prepare an undrawn nonwoven fabric having a basis weight of 140 g / m ² . The average fiber diameter of the nonwoven fabric was 12 μm.

Next, a raw material of a copolymer of ethylene terephthalate and ethylene isophthalate having an ethylene isophthalate copolymerization amount of 25 mol% was supplied to a hopper, and then a T-die die was formed using an extruder having a screw diameter of 40 mm. It was extruded at a temperature of 270 ° C. and cast on a cooling drum (60 ° C.) having a diameter of 600 mm to form an unstretched film.

The unstretched nonwoven fabric was placed on the unstretched film, supplied to a heating roll, and thermocompressed at a roll temperature of 80 ° C. The film surface of the laminated sheet thus obtained was preheated at 80 ° C., and then the nonwoven fabric surface was preheated at 95 ° C., and then stretched with a silicone rubber stretching roll (pressing roll pressure 2.0 N / cm) heated to 93 ° C. 2. In the length direction
It was stretched 5 times. Further, it is sent to a tenter type stretching machine and
The film was stretched 4.0 times in the width direction at 00 ° C. Further, heat treatment was performed at 100 ° C. for 5 seconds in the tenter to prepare a heat-sensitive stencil sheet having a thickness of 60 μm. A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying. The basis weight of the polyester nonwoven fabric of the obtained base paper was 10 g / m ² , the average fiber diameter was 8 μm, the crystal melting energy was 55 J / g, the melting point was 255 ° C., and the intrinsic viscosity was 0.48.
It was 5. The thickness of the polyester film alone was 0.8 μm, the crystal melting energy was 10 J / g, and the melting point was 190 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 4N, a printability of ○, and a durability of A. Example 2 An unstretched nonwoven fabric having a basis weight of 70 g / m ² was prepared under the same conditions as in Example 1 except for the conveyor speed.

Next, a copolymer of ethylene terephthalate and ethylene isophthalate was used, and a raw material having an ethylene isophthalate copolymerization amount of 25 mol% was used.
An unstretched film was prepared under the same conditions as described above. On the unstretched film, the unstretched nonwoven fabric was laminated and stretched under the same conditions as in Example 1 to prepare a 55 mm thick heat-sensitive stencil sheet.
A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying. The fiber weight of the polyester nonwoven fabric of the obtained base paper is 6 g / m ² , the average fiber diameter is 8 μm, the crystal melting energy is 55 J / g, and the melting point is 25.
At 5 ° C., the intrinsic viscosity was 0.485. The thickness of the polyester film alone was 0.8 μm, the crystal melting energy was 28 J / g, and the melting point was 218 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 2N, a printability of ○, and a durability of B.

Example 3 An unstretched nonwoven fabric having a basis weight of 140 g / m ² prepared in Example 1 was prepared.

Then, a copolymer of ethylene terephthalate and ethylene isophthalate was used, and a raw material having an ethylene isophthalate copolymerization amount of 15 mol% was used in Example 1.
An unstretched film was prepared under the same conditions as described above. On the unstretched film, the unstretched nonwoven fabric was superimposed and stretched under the same conditions as in Example 1 to prepare a heat-sensitive stencil sheet having a thickness of 70 μm.
A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying. The fiber weight of the polyester nonwoven fabric of the obtained base paper is 10 g / m ² , the average fiber diameter is 8 μm, the crystal melting energy is 55 J / g, and the melting point is 2
At 55 ° C., the intrinsic viscosity was 0.485. The thickness of the polyester film alone was 0.8 μm, the crystal melting energy was 28 J / g, and the melting point was 218 ° C. The obtained base paper had a tear propagation resistance of 4.2 N in the longitudinal direction, a printability of ○, and a durability of A.

Example 4 An unstretched nonwoven fabric having a basis weight of 140 g / m ² prepared in Example 1 was prepared.

Next, ethylene terephthalate and 2,6
2,6-naphthalenedicarboxylate and copolymer
Using a raw material having a naphthalenedicarboxylate copolymerization amount of 25 mol%, an unstretched film was prepared under the same conditions as in Example 1. The unstretched nonwoven fabric was laminated on the unstretched film and stretched under the same conditions as in Example 1 to prepare a heat-sensitive stencil sheet having a thickness of 68 μm. A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying. The basis weight of the polyester nonwoven fabric of the obtained base paper is 10 g / m ² , the average fiber diameter is 8 μm, the crystal melting energy is 55 J / g, the melting point is 255 ° C., and the intrinsic viscosity is 0.4.
85. The thickness of the polyester film alone was 0.8 μm, the crystal melting energy was 20 J / g, and the melting point was 192 ° C. The obtained base paper had a tear propagation resistance of 4.1 N in the longitudinal direction, a printability of ○, and a durability of A.

Example 5 A raw material having a copolymerization amount of ethylene terephthalate and ethylene isophthalate having a copolymerization amount of ethylene isophthalate of 5 mol% was used, and the average fiber diameter was 12 μm under the same conditions as in Example 1. Fiber weight 140
g / m ² of an unstretched nonwoven fabric was prepared.

Next, an unstretched film was prepared using the same raw materials as in Example 1. The unstretched nonwoven fabric was superimposed on the unstretched film, and stretched under the same conditions as in Example 1 to prepare a 67 mm thick heat-sensitive stencil sheet. At the entrance of the tenter on the film surface of the base paper, a wax-based release agent was weighed to 0.1 g after stretching and drying using a gravure coater.
/ M ² . The basis weight of the polyester nonwoven fabric of the obtained base paper was 10 g / m ² , the average fiber diameter was 8 μm, the crystal melting energy was 42 J / g, the melting point was 245 ° C., and the intrinsic viscosity was 0.485. The polyester film alone has a thickness of 0.8 μm and a crystal melting energy of 10 J.
/ G, melting point 190 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 3 N, a printability of ○, and a durability of A.

Example 6 A copolymer of 1,4-cyclohexane dimethylene terephthalate and 1,4-cyclohexane dimethylene isophthalate, where the copolymerization amount of 1,4-cyclohexane dimethylene isophthalate is 30 mol%. The average fiber diameter was 12 μm and the basis weight was 1 under the same conditions as in Example 1 except that the die temperature was set to 300 ° C. using the raw materials.
An unstretched nonwoven fabric of 40 g / m ² was prepared.

Next, an unstretched film was prepared using the same raw materials as in Example 1. The unstretched non-woven fabric was laminated on the unstretched film and stretched under the same conditions as in Example 1 to prepare a 75 mm thick heat-sensitive stencil sheet. At the entrance of the tenter on the film surface of the base paper, a wax-based release agent was weighed to 0.1 g after stretching and drying using a gravure coater.
/ M ² . The basis weight of the polyester nonwoven fabric of the obtained base paper was 10 g / m ² , the average fiber diameter was 8 μm, the crystal melting energy was 20 J / g, the melting point was 260 ° C., and the intrinsic viscosity was 1.000. The thickness of the polyester film alone was 0.8 μm, and the crystal melting energy was 9 J /
g, melting point was 190 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 4.5 N, a printability of ○, and a durability of A.

Example 7 An average fiber diameter of 12 μm and a basis weight of 140 g / m ² were obtained under the same conditions as in Example 1 using a polyethylene terephthalate raw material having an intrinsic viscosity of 0.505.
Was produced.

Next, an unstretched film was prepared using the same raw materials as in Example 1. The unstretched nonwoven fabric was superimposed on the unstretched film, and stretched under the same conditions as in Example 1 except that the nonwoven fabric surface was preheated at 97 ° C. to prepare a heat-sensitive stencil sheet having a thickness of 65 μm. A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying. The fiber basis weight of the polyester nonwoven fabric of the obtained base paper is 10 g.
/ M ² , average fiber diameter 8 μm, crystal melting energy 5
The melting point was 5 J / g, the melting point was 255 ° C., and the intrinsic viscosity was 0.485. The thickness of the polyester film alone is 0.8
μm, crystal melting energy is 10 J / g, melting point is 190
° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 5 N, a printability of ○, and a durability of A.

Example 8 An average fiber diameter of 12 μm and a basis weight of 140 g / m ² were obtained under the same conditions as in Example 1 using a polyethylene terephthalate raw material having an intrinsic viscosity of 0.550.
Was produced.

Next, an unstretched film was prepared using the same raw materials as in Example 1. The unstretched nonwoven fabric was overlaid on the unstretched film, and stretched under the same conditions as in Example 1 except that the nonwoven fabric surface was preheated at 100 ° C. to prepare a heat-sensitive stencil sheet having a thickness of 70 μm. A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying.
The fiber basis weight of the obtained base paper polyester nonwoven fabric is 10
g / m ² , average fiber diameter was 8 μm, crystal melting energy was 55 J / g, melting point was 255 ° C., and intrinsic viscosity was 0.485. The thickness of the polyester film alone is 0.1.
8 μm, crystal melting energy 11 J / g, melting point 19
It was 0 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 6 N, a printability of Δ, and a durability of A.

Comparative Example 1 An unstretched nonwoven fabric having a basis weight of 140 g / m ² prepared in Example 1 was prepared.

Next, in Example 1, a copolymer of ethylene terephthalate and ethylene isophthalate was used in which a raw material having an ethylene isophthalate copolymerization amount of 25 mol% was used.
An unstretched film was prepared under the same conditions as described above. On the unstretched film, the unstretched non-woven fabric is superimposed, and both the film surface and the non-woven fabric surface are preheated at 90 ° C., and then heated to 100 ° C. by a ceramic stretching roll (pressing roll pressure 8.0 N / c).
m), it was stretched 3.5 times in the length direction. Furthermore, it was sent to a tenter type stretching machine and stretched 4.0 times in the width direction at 100 ° C. Further, heat treatment was performed at 100 ° C. for 5 seconds in the tenter to prepare a heat-sensitive stencil sheet having a thickness of 60 μm. A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying. The basis weight of the polyester nonwoven fabric of the obtained base paper is 10 g / m ² , and the average fiber diameter is 8 μm.
m, crystal melting energy is 55 J / g, melting point is 255
° C, the intrinsic viscosity was 0.485. The thickness of the polyester film alone was 0.8 μm, the crystal melting energy was 10 J / g, and the melting point was 190 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 0.2 N, a printability of ○, and a durability of C.

Comparative Example 2 An unstretched nonwoven fabric having a basis weight of 140 g / m ² prepared in Example 1 was prepared.

Next, ethylene terephthalate and 2,6
2,6 in a copolymer with naphthalene dicarboxylate
A naphthalene dicarboxylate copolymerization amount of 25 mol%
An unstretched film was prepared under the same conditions as in Example 1 using the following raw material. The unstretched nonwoven fabric is superimposed on the unstretched film, and both the film surface and the nonwoven fabric surface are preheated at 95 ° C., and then heated by a ceramic stretching roll (pressing roll pressure 4.0 kg / m) heated to 110 ° C. 2. In the length direction
It was stretched 5 times. Further, it is sent to a tenter type stretching machine and
The film was stretched 4.0 times in the width direction at 10 ° C. Further, heat treatment was performed at 100 ° C. for 5 seconds in the tenter to prepare a 67 mm thick heat-sensitive stencil sheet. A wax-based release agent was applied to the film surface of the base paper at the entrance of the tenter using a gravure coater at a weight of 0.1 g / m ² after stretching and drying. The basis weight of the polyester nonwoven fabric of the obtained base paper was 10 g / m ² , the average fiber diameter was 8 μm, the crystal melting energy was 55 J / g, the melting point was 255 ° C., and the intrinsic viscosity was 0.48.
It was 5. The thickness of the polyester film alone was 0.8 μm, the crystal melting energy was 20 J / g, and the melting point was 192 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 0.2 N, a printability of ○, and a durability of C.

Comparative Example 3 Using a raw material having a copolymerization amount of ethylene terephthalate and ethylene isophthalate with a copolymerization amount of ethylene isophthalate of 25 mol%, the average fiber diameter was 12 μm under the same conditions as in Example 1. Fiber weight 14
An unstretched nonwoven fabric of 0 g / m ² was prepared.

Next, an unstretched film was prepared using the same raw materials as in Example 1. The unstretched nonwoven fabric was superimposed on the unstretched film and stretched under the same conditions as in Example 1 to prepare a heat-sensitive stencil sheet having a thickness of 62 μm. At the entrance of the tenter on the film surface of the base paper, a wax-based release agent was weighed to 0.1 g after stretching and drying using a gravure coater.
/ M ² . The basis weight of the polyester nonwoven fabric of the obtained base paper was 10 g / m ² , the average fiber diameter was 8 μm, the crystal melting energy was 9 J / g, the melting point was 190 ° C., and the intrinsic viscosity was 0.485. The thickness of the polyester film alone was 0.8 μm, and the crystal melting energy was 10 J /
g, melting point was 190 ° C. The obtained base paper had a tear propagation resistance in the longitudinal direction of 0.3 N, a printability of x, and a durability of D.

[Comparative Example 4] Thin paper having a fiber weight of 10 g / m ^{2 and} 100% of natural fibers made from Manila hemp was prepared. Next, an unstretched film was prepared under the same conditions as in Example 1 by using a raw material having a copolymerization amount of ethylene terephthalate and ethylene isophthalate having an ethylene isophthalate copolymerization amount of 15 mol%. The unstretched film is stretched 3.6 times in the length direction between 95 ° C. heating rolls alone, then sent to a tenter type stretching machine, and stretched 4.2 times in the width direction at 100 ° C. The inside was heat-treated at 120 ° C. for 5 seconds, and the obtained film having a thickness of 0.8 μm was bonded using a vinyl acetate resin. The adhesive application amount was 1 g / m ² . Next, a wax-based release agent was applied to the surface of the film at a weight of 0.1 g / m ² after drying to prepare a heat-sensitive stencil sheet. The obtained base paper had a tear propagation resistance in the longitudinal direction of 0.3 N, a printability of Δ, and a durability of D.

[0074]

[Table 1]

[0075]

According to the present invention, high-definition printability is excellent,
Particularly, a heat-sensitive stencil sheet having excellent durability has been provided.

Claims (5)

[Claims] 1. A heat-sensitive stencil printing paper characterized in that a polyester film and a polyester non-woven fabric are joined together without an adhesive therebetween, and have a tear propagation resistance in the longitudinal direction of 1 to 8N. 2. The tear propagation resistance in the longitudinal direction is 1.5 to 5
The heat-sensitive stencil sheet according to claim 1, wherein N is N. 3. The heat-sensitive stencil sheet according to claim 1, wherein the polyester film has a crystal melting energy of 2 to 45 J / g. 4. The polyester nonwoven fabric has a crystal melting energy of 20 to 65 J / g.
3. The base paper for heat-sensitive stencil printing according to any one of 3. 5. The heat-sensitive stencil sheet according to claim 1, wherein the melting point of the polyester nonwoven fabric is higher than the melting point of the polyester film by 5 ° C. or more.