JP2000118163A - Unwoven fabric for heat sensitive stencil printing original paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To strengthen the nerve of a fabric and permit the restriction of generation of creasing even when the weight of the fabric is reduced while improving a printed image by a method wherein both of a principal fiber, constituting the part of a skeleton and the non-oriented fiber, constituting the part of binder, are formed of a polyester, whose principal constituent is polyethylene naphthalate. SOLUTION: An unwoven fabric is constituted of a principal fiber, constituting the part of a skeleton, and a non-oriented fiber, constituting the part of binder. Both of the principal fiber, constituting the part of a skeleton, and the non-oriented fiber, constituting the part of binder and low in the orientation of fibers, are constituted of a polyester, whose principal constituent is polyethylene naphthalate, and whose ethylene naphthalate unit is at least 80 mol% or more in a repeating unit. According to this method, the nerve of the fabrics can be strengthened and the fiber can be used even when the weight thereof is reduced whereby a printing press can be compacted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a nonwoven fabric for heat-sensitive stencil printing base paper. More specifically, the present invention relates to a non-woven fabric for a heat-sensitive stencil printing paper, which is used for a porous support constituting the heat-sensitive stencil printing paper, and particularly has a strong stiffness, hardly generates wrinkles even when the basis weight is reduced, and provides a good image. is there.

[0002]

2. Description of the Related Art Conventionally, as heat-sensitive stencil printing paper, porous paper such as thin paper made of a thermoplastic resin film such as vinylidene chloride-vinyl chloride copolymer film, polypropylene film or polyester film and natural fibers such as manila hemp has been used. A structure in which a support and a support are bonded together with an adhesive is well known (JP-B-41-7623 or JP-A-51-2513). However, tissue paper containing natural fibers such as Manila hemp is susceptible to humidity, so it absorbs and expands especially in humid conditions such as during the rainy season. For this reason, the base paper laminated with the thermoplastic resin film has a drawback that it is curled and changes in dimensions are large.

[0003] As a porous support, a mixture of natural fibers and some synthetic fibers may be used (Japanese Patent Publication No. 48-82).
No. 17 or JP-A-60-217197),
Although it has been proposed to impregnate the entire porous support with a synthetic resin (Japanese Patent Publication No. 55-47997), no satisfactory resin has yet been obtained. For example, a porous support mixed with a chemical fiber hardly contributes to dimensional stabilization when wet because the chemical fiber has poor adhesion to natural fibers, and a case where the entire porous support is impregnated with a synthetic resin. In addition, a reduction in print sharpness due to poor transmission of the printing ink is inevitable.

Further, a nonwoven fabric using 100% of a hydrophobic fiber such as polyester as a porous support has been proposed (JP-A-59-2896 and JP-A-60-90).
JP-A-38193, JP-A-2-67197 or JP-A-3-76894), although the dimensional stability at the time of wetting is improved, but shrinkage occurs due to heat received from the thermal head during plate making. I found that there was.

[0005] In addition, a continuous roll system is used to supply the base paper in the printing press. In order to make the printing press compact, rigidity enough to allow the base paper to be conveyed has a rigidity that can be achieved in a place where the basis weight is as small as possible. However, conventional supports such as those described above have not been satisfactory.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems by defining the fibers constituting the non-woven fabric used as a porous support. An object of the present invention is to provide a nonwoven fabric which suppresses wrinkles and provides a good image.

[0007]

According to the present invention, which achieves the above-mentioned object, both the main fiber constituting the skeleton portion and the undrawn fiber constituting the binder portion are made of a polyester mainly composed of polyethylene naphthalate. A non-woven fabric for thermosensitive stencil printing characterized by the following.

[0008]

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

The nonwoven fabric according to the present invention comprises a main fiber constituting a skeleton portion and an undrawn fiber having a thermal bonding effect constituting a binder portion.

[0010] Those in which the main fibers are bonded to each other with an adhesive or the like without using undrawn fibers are not preferable because the adhesive inhibits the transmission of ink and lowers the image clarity.

In the present invention, both the main fibers constituting the skeleton portion and the undrawn fibers constituting the binder portion are made of a polyester mainly composed of polyethylene naphthalate.

[0012] Polyester mainly composed of polyethylene naphthalate means at least 70 mol% of repeating units.
Is an ethylene naphthalate unit. Preferably it is 80 mol% or more, more preferably 85 mol% or more.
Mol% or more. If the content of the ethylene naphthalate unit in the polyester constituting the main fiber is less than 70 mol%, the rigidity is undesirably reduced. In addition, if the content of the ethylene naphthalate unit in the polyester constituting the undrawn fiber is less than 70 mol%, not only the rigidity is lowered but also the shrinkage during plate making is undesirably large. In addition, if it is 30 mol% or less of the repeating unit, it may be modified with the following copolymer component.

Examples of the copolymer component include components having a divalent ester-forming functional group such as a dicarboxylic acid component and a diol component. More specifically, terephthalic acid, isophthalic acid, 4,4'- Diphenyl dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, 4,
Aromatic dicarboxylic acids such as 4'-diphenylsulfone dicarboxylic acid and 5-sodium sulfoisophthalic acid, aliphatic dicarboxylic acids such as succinic acid, adipic acid, suberic acid and sebacic acid, and alicyclic rings such as 1,4-cyclohexanedicarboxylic acid Aliphatic dicarboxylic acid, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, Examples thereof include diols such as 1,4-cyclohexanedimetal, diethylene glycol, polyalkylene glycol, and 2,2′-bis (4′-β-hydroxyethoxyphenyl) propane. These may be used alone or in combination of two or more, and further, an oxyacid such as hydroxybenzoic acid may be partially copolymerized.

The main fiber in the present invention preferably has a highly oriented birefringence Δn of 0.15 to 0.25, more preferably 0.18 to 0.25. When the birefringence is in the range of 0.15 to 0.25, the stiffness is sufficient, which is preferable.

In the present invention, the unstretched fiber constituting the binder portion has a low fiber orientation, and Δn is preferably 0.12 or less. More preferably 0.10
Or less, more preferably 0.08 or less. When the orientation of the fiber is low, the adhesive force with the main fiber is improved, and the fiber is less likely to fall off, which is preferable. If Δn is 0.12 or less, a sufficient adhesive strength can be obtained.

The fiber diameter of the main fibers constituting the nonwoven fabric of the present invention is preferably 1 to 12 μm, more preferably 3 to 8 μm. Further, the fiber diameter of the undrawn fiber is preferably 4 to 30 μm, more preferably 5 to 20 μm. The smaller the fiber diameter is, the more uniform the printed image becomes, which is preferable. However, the above range is a preferable range from the viewpoint of ease of production. Both the main fiber and the unstretched fiber may have any cross-sectional shape, but the unstretched fiber is preferably flat. In this case, it is particularly preferable that the portion corresponding to the major axis of the cross section is within the above-mentioned fiber diameter.
Further, both the main fiber and the undrawn fiber may be continuous fibers, but more preferably short fibers of about 1 to 15 mm.

In the present invention, the mixing ratio of the main fiber and the undrawn fiber constituting the binder portion is 50:50 to 50:50.
A range of 95: 5 is preferred, and a range of 70:30 to 90:10 is more preferred. When the mixing ratio of the main fibers is high, the stiffness increases, and when the mixing ratio of the undrawn fibers increases, the falling off of the fibers can be suppressed, and the above range is a preferable range in which the above range can be balanced.

The basis weight of the nonwoven fabric of the present invention is preferably 2
１５15 g / m ² , more preferably 3 to 12 g / m ^2
2 If the basis weight is ² to 15 g / m ² , sufficient strength can be obtained. When the basis weight is 3 to 12 g / m ² ,
Further, a good image can be obtained with sufficient strength.

The thickness of the nonwoven fabric of the present invention is preferably 15
To 70 μm, more preferably 25 to 60 μm. When the thickness is 15 to 70 μm, ink permeability is good and image quality is good. Further, when the thickness is 25 to 60 μm, loss of ink at the time of plate discharge is small.

The tensile modulus of the nonwoven fabric of the present invention is preferably 0.15 N / mm or more, more preferably 0.18 N / mm.
mm or more. When the tensile modulus is 0.15 N / mm or more, no wrinkles occur when the base paper is conveyed in the printing press. When it is 0.18 N / mm or more, elongation during printing is suppressed.

The nonwoven fabric of the present invention is mainly intended for fibers made of polyester. However, it is acceptable to mix a third component which does not impair the basic performance such as rigidity of the nonwoven fabric, ink permeability and shrinkage. Absent. Examples of the third component include natural fibers such as cucumber, honey bean, and manila hemp, and synthetic fibers such as polyvinyl alcohol, acrylic, and aramid.

Next, the method for producing the nonwoven fabric of the present invention will be described below.

In the present invention, the polyester is, for example,
After the dicarboxylic acid component is directly esterified with the diol component, the product of this reaction is heated under reduced pressure to remove the excess diol component and polycondensate the dicarboxylic acid component. 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, an alkali metal, an alkaline earth metal, manganese, cobalt, zinc, antimony, germanium, and a titanium compound can be used as a reaction catalyst.

In the present invention, if necessary, the polyester may contain 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.

The polyester used for the unstretched fiber and the main fiber may be one mainly composed of polyethylene naphthalate, and may slightly vary depending on copolymerization, additives and the like. Next, undrawn fibers can be obtained by a melt spinning method using a polyester mainly composed of polyethylene naphthalate.

The main fiber can be obtained by using a polyester mainly composed of polyethylene naphthalate and then subjecting it to melt spinning and then drawing.

Each of the main fiber and the undrawn fiber is preferably cut into a predetermined length to be a short fiber.

Each of the obtained fibers is mixed and dispersed in water with a pulper or a beater so as to have a predetermined ratio, and then formed with a circular, short or long net paper machine, and then subjected to hot calender pressing. The raw cotton is obtained.

For the nonwoven fabric of the present invention, the calendering conditions are as follows. For example, the papermaking sheet formed at a papermaking dryer temperature of 110 to 150 ° C. is heated to a temperature lower than the lower one of the melting temperatures of the polyesters of the main fiber and the undrawn fiber. At a temperature of, for example, 180 to 240 ° C.

As the calendering method, either a single-stage method or a multi-stage method can be used.

If necessary, antistatic treatment may be applied to the raw cotton or the nonwoven fabric constituting the nonwoven fabric, or a hydrophilic treatment may be performed to increase the ink permeability of the nonwoven fabric.

In order to form a heat-sensitive stencil sheet using the nonwoven fabric of the present invention, for example, an acrylic, vinyl chloride, polyester, vinyl acetate, urethane, etc. It is possible to apply an adhesive of a system or the like so that the dry application amount is 0.1 to 1 g / m ² , and to superimpose and press, heat, dry, or irradiate with ultraviolet rays or the like. Further, in order to prevent fusion with the thermal head, a release agent such as a fluorine-based, silicone-based, or surfactant may be provided on the surface of the film opposite to the nonwoven fabric side.

[0033]

[Method of measuring characteristics] (1) Average fiber diameter: The average fiber diameter is
Ten photographs were taken of arbitrary 10 places of the non-woven fabric with an electron microscope at a magnification of 2000 times, and arbitrary 1 was taken per photograph.
The diameters of five fibers were measured, and the measurement was performed on ten photographs. The diameters of a total of 150 fibers were measured, and the average value was shown.

(2) Birefringence (Δn): A birefringence (Δn) was calculated by using a sodium lamp as a light source with a polarizing microscope and determining the retardation of the sample by the Berk compensator method while immersing the sample in α-bromonaphthalene.

(3) Weight per unit area: A nonwoven fabric was cut into a size of 20 × 20 cm, the weight was measured, and the value converted to the weight per square meter was used.

(4) Tensile elastic modulus: A base paper was cut in a length direction or a width direction by 20 mm × 150 mm and gripped by an air chuck of a “Tensilon” tensile tester (manufactured by Toyo Sokki Co., Ltd.) to determine the elastic modulus. It was measured. The measurement conditions were a chuck interval of 50 mm and a tensile speed of 50 mm / min, and a load-elongation diagram (SS curve) was recorded. It was calculated by dividing the tensile load at an elongation of 1% by the sample width from the initial rising slope of the SS curve.

(5) Plate formation wrinkle: The base paper was supplied to "RISOGRAPH" GR375 manufactured by Riso Kagaku Kogyo Co., Ltd., and a plate making operation was performed using a plain paper as an original. After the plate making operation, the state of the base paper wound around the plate cylinder was visually observed. This was repeated five times and judged according to the following criteria.

When no wrinkles were generated, the result was evaluated as “○”. When wrinkles were slightly observed at the end within 2 times out of 5 times, “△” was performed 3 times or more out of 5 times. In the case of what I saw, "x", "o" or "△" is a practically usable level.

(6) Print wrinkle: The base paper was supplied to RISOGRAPH GR375 manufactured by Riso Kagaku Kogyo Co., Ltd., and plate making and printing were performed using a black solid document as an original. 1
After printing 00 sheets, the state of the base paper wrapped around the plate cylinder was visually observed and judged according to the following criteria.

[0040] Wrinkles were not observed at all. "O". Wrinkles were slightly observed at the edges. "△". Wrinkles were observed at a plurality or at the center. “○” or “△” is a practically usable level.

(7) Image quality: base paper is Riso Kagaku Kogyo Co., Ltd.
The plate was supplied to "RISOGRAPH" GR375, and plate making and printing were performed using a black solid document as a document. Twenty sheets were printed, and the state of white spots and density unevenness of the twentieth printed image was visually determined based on the following criteria.

<White spots> No white spots, “O” White spots slightly observed, “△” White spots, conspicuous spots, “×” <Light / shade unevenness> There are no samples at all, “○” unevenness is slightly observed, “も の” unevenness is noticeable, and “×” “○” or “△” is a practically usable level.

[0043]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Example 1 [Preparation of main fiber] A polyethylene naphthalate chip was melted at 295 ° C.
C. and discharged at a speed of 1000 m / min. Next, the undrawn yarn is drawn at a magnification of 3.8 times in an atmosphere of 110 ° C., subjected to a tension heat treatment at 200 ° C., a relaxation heat treatment at 140 ° C., cut into 5 mm, and birefringent at an average fiber diameter of 5 μm. Was 0.18.

[Production of Undrawn Fiber] On the other hand, a polyethylene naphthalate chip was melted at 295 ° C.
At 290 ° C. and cut into 5 mm to obtain undrawn fiber a having an average fiber diameter of 8 μm and a birefringence of 0.05.

[Paper making] The main fiber A and the undrawn fiber a
After thoroughly mixing and dispersing in a pulper at a weight ratio of 0:20, the mixture was heated and dried at a speed of 10 m / min and a surface temperature of a Yankee dryer of 130 ° C. using a circular paper machine. Estimated basis weight is 8
g / m ² .

Then, the metal roll surface temperature was 215 ° C., and the linear pressure was 20 kg / c using a metal / elastic roll calendering machine.
By pressing under a condition of m, a nonwoven fabric having a thickness of 25 μm was obtained.

[Production of base paper] A 2 μm-thick biaxially stretched film made of a copolymer of ethylene terephthalate and ethylene isophthalate (isophthalic acid copolymerization amount: 15 mol%) was prepared by using a vinyl acetate adhesive. The above nonwoven fabric was adhered, and a silicone release material was applied to the opposite surface of the film from the nonwoven fabric side to obtain a base paper.

[Evaluation] The properties of the obtained base paper are shown in Table 1. It can be seen that the base paper has excellent dimensional stability during plate making and has good image quality.

Comparative Example 1 [Production of Main Fiber] A polyethylene terephthalate chip was melted at 290 ° C., and was passed through a die having 900 holes.
It was discharged at 5 ° C. and wound up at a speed of 1000 m / min. Next, the undrawn yarn is drawn at a magnification of 3.8 times in warm water at 80 ° C., subjected to a tension heat treatment at 200 ° C., a relaxation heat treatment at 125 ° C., cut into 5 mm, and cut into a fiber having an average fiber diameter of 5 μm. A main fiber B having a refraction of 0.20 was obtained.

[Production of Undrawn Fiber] On the other hand, a polyethylene terephthalate chip was melted at 290 ° C.
Discharge at 285 ° C through the base of No. 0, cut to 5mm,
An undrawn fiber b having an average fiber diameter of 8 μm and a birefringence of 0.05 was obtained.

[Paper making] The main fiber B and the undrawn fiber b
After thoroughly mixing and dispersing in a pulper at a weight ratio of 0:20, the mixture was heated and dried at a speed of 10 m / min and a surface temperature of a Yankee dryer of 130 ° C. using a circular paper machine. Estimated basis weight is 8
g / m ² .

Next, the metal roll surface temperature was 210 ° 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 25 μm was obtained.

[Production of base paper] A 2 μm-thick biaxially stretched film made of a copolymer of ethylene terephthalate and ethylene isophthalate (isophthalic acid copolymerization amount: 15 mol%) was prepared by using a vinyl acetate adhesive. The above nonwoven fabric was adhered, and a silicone release material was applied to the opposite surface of the film from the nonwoven fabric side to obtain a base paper.

[Evaluation] The properties of the obtained base paper are shown in Table 1. As shown in Table 1, wrinkles occurred when the plate was formed and the printing was repeated, and the image was defective.

Comparative Example 2 [Papermaking] The main fiber A and the undrawn fiber b were thoroughly mixed and dispersed in a pulper at a weight ratio of 80:20. 1
It was dried by heating at 30 ° C. The weight per unit area was 8 g / m ² .

Then, using a metal / elastic roll calendering machine, the metal roll surface temperature was 210 ° C., and the linear pressure was 15 kg / cm.
Under the following conditions to obtain a nonwoven fabric having a thickness of 25 μm.

[Production of base paper] A 2-μm-thick biaxially stretched film made of a copolymer of ethylene terephthalate and ethylene isophthalate (isophthalic acid copolymerization amount: 15 mol%) was prepared by using a vinyl acetate adhesive. The above nonwoven fabric was adhered, and a silicone release material was applied to the opposite surface of the film from the nonwoven fabric side to obtain a base paper.

[Evaluation] The properties of the obtained base paper are shown in Table 1. As a result, wrinkles were easily generated and the image was insufficient.

Example 2 [Production of Main Fiber] A polyethylene naphthalate chip was melted at 295 ° C.
C. and discharged at a speed of 1000 m / min. Next, this undrawn yarn is drawn at a magnification of 3.2 times in an atmosphere of 110 ° C., subjected to a tension heat treatment at 200 ° C., and further subjected to a relaxation heat treatment at 140 ° C., and then cut into 5 mm to have an average fiber diameter of 5 μm.
As a result, a main fiber B having a birefringence of 0.15 was obtained.

[Paper making] The main fiber B and the undrawn fiber a
After thoroughly mixing and dispersing in a pulper at a weight ratio of 0:20, the mixture was heated and dried at a speed of 10 m / min and a surface temperature of a Yankee dryer of 130 ° C. using a circular paper machine. Estimated basis weight is 8
g / m ² .

Then, using a metal / elastic roll calendering machine, the metal roll surface temperature is 215 ° C., and the linear pressure is 20 kg / c.
By pressing under a condition of m, a nonwoven fabric having a thickness of 25 μm was obtained.

[Production of base paper] A 2-μm-thick biaxially stretched film made of a copolymer of ethylene terephthalate and ethylene isophthalate (isophthalic acid copolymerization amount: 15 mol%) was prepared by using a vinyl acetate adhesive. The above nonwoven fabric was adhered, and a silicone release material was applied to the opposite surface of the film from the nonwoven fabric side to obtain a base paper.

[Evaluation] The characteristics of the obtained base paper are shown in Table 1. It can be seen that wrinkles are less generated and the image quality is good.

Example 3 Production of Main Fibers A polyethylene naphthalate chip was melted at 295 ° C.
C. and discharged at a speed of 1000 m / min. Next, this undrawn yarn is drawn at a magnification of 4.5 times in hot water at 110 ° C., subjected to a tension heat treatment at 200 ° C., a relaxation heat treatment at 140 ° C., cut into 5 mm, and birefringent at an average fiber diameter of 5 μm. Was 0.22.

[Paper making] The main fiber C and the undrawn fiber a
After thoroughly mixing and dispersing in a pulper at a weight ratio of 0:20, the mixture was heated and dried at a speed of 10 m / min and a surface temperature of a Yankee dryer of 130 ° C. using a circular paper machine. Estimated basis weight is 8
g / m ² .

Then, using a metal / elastic roll calendering machine, the metal roll surface temperature was 215 ° C., and the linear pressure was 20 kg / cm.
Under the following conditions to obtain a nonwoven fabric having a thickness of 25 μm.

[Production of base paper] A 2-μm-thick biaxially stretched film made of a copolymer of ethylene terephthalate and ethylene isophthalate (isophthalic acid copolymerization amount: 15 mol%) was prepared by using a vinyl acetate adhesive. The above nonwoven fabric was adhered, and a silicone release material was applied to the opposite surface of the film from the nonwoven fabric side to obtain a base paper.

[Evaluation] The characteristics of the obtained base paper are shown in Table 1. It can be seen that the shrinkage during plate making is small and the image quality is good.

Example 4 [Production of undrawn fiber] On the other hand, a polyethylene naphthalate chip was melted at 290 ° C, discharged at 280 ° C through a die having 900 holes, cut into 5 mm, and cut to an average fiber diameter of 5 µm.
As a result, an undrawn fiber b having a birefringence of 0.12 was obtained.

[Paper making] The main fiber A and the undrawn fiber b
After thoroughly mixing and dispersing in a pulper at a weight ratio of 0:20, the mixture was heated and dried at a speed of 10 m / min and a surface temperature of a Yankee dryer of 130 ° C. using a circular paper machine. Estimated basis weight is 8
g / m ² .

Then, the metal roll surface temperature was 210 ° 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 25 μm was obtained.

[Production of base paper] A 2-μm-thick biaxially stretched film made of a copolymer of ethylene terephthalate and ethylene isophthalate (isophthalic acid copolymerization amount: 15 mol%) was prepared by using a vinyl acetate adhesive. The above nonwoven fabric was adhered, and a silicone release material was applied to the opposite surface of the film from the nonwoven fabric side to obtain a base paper.

[Evaluation] The properties of the obtained base paper are shown in Table 1. The shrinkage during plate making was small and the image quality was good.

Example 5 [Paper making] After sufficiently mixing and dispersing the main fiber B and the undrawn fiber b at a weight ratio of 80:20 in a pulper, the speed was 10 m / min using a circular paper machine, and the surface temperature of a Yankee dryer. 1
It was dried by heating at 30 ° C. The weight per unit area was 8 g / m ² .

Then, the metal roll surface temperature was 210 ° 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 25 μm was obtained.

[Production of base paper] A 2-μm-thick biaxially stretched film made of a copolymer of ethylene terephthalate and ethylene isophthalate (isophthalic acid copolymerization amount: 15 mol%) was prepared by using a vinyl acetate adhesive. The above nonwoven fabric was adhered, and a silicone release material was applied to the opposite surface of the film from the nonwoven fabric side to obtain a base paper.

[Evaluation] The properties of the obtained base paper are shown in Table 1. The shrinkage during plate making was small, and the image quality was usable.

Examples 6 to 8 and Comparative Example 3 A base paper was obtained in the same manner as in Example 1 except that the weight ratio between the main fiber A and the undrawn fiber a was changed as shown in Table 1.

[Evaluation] The properties of the obtained base paper are shown in Table 1. The nonwoven fabric of the present invention has excellent dimensional stability during plate making.
It can be seen that the image quality is also good.

Examples 5 and 6 Base papers were obtained in the same manner as in Example 1 except that the basis weight of the paper was changed to 6 and 10 g / m ² .

[Evaluation] The properties of the obtained base paper are shown in Table 1. The nonwoven fabric of the present invention has excellent dimensional stability during plate making.
It can be seen that the image quality is also good.

[0083]

[Table 1]

[0084]

The nonwoven fabric of the present invention has a strong stiffness and can provide a support particularly suitable for heat-sensitive stencil printing base paper. Also. Since the printer can be used even if the basis weight is reduced, the printing machine can be made compact and defects such as white spots during printing can be suppressed.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H114 AB23 DA56 EA04 EA06 FA02 FA10 4F100 AK22G AK42B AK79D AS00A BA02 BA04 BA07 BA10A BA10D DG01A DG15A EJ37A GB90 JK04 JK07A JL04 JL14C JN18 FA13GA4 GA4

Claims (5)

[Claims] 1. A non-woven fabric for heat-sensitive stencil printing paper, wherein both the main fiber constituting the skeleton portion and the unstretched fiber constituting the binder portion are made of polyester mainly composed of polyethylene naphthalate. 2. The nonwoven fabric for heat-sensitive stencil printing paper according to claim 1, wherein the birefringence of the main fiber is 0.15 to 0.25. 3. The nonwoven fabric for heat-sensitive stencil printing paper according to claim 1, wherein the birefringence of the undrawn fiber is 0.12 or less. 4. The heat-sensitive material according to claim 1, wherein the mixing ratio of the main fiber and the undrawn fiber constituting the binder portion is in the range of 50:50 to 95: 5. Non-woven fabric for stencil printing paper. 5. The non-woven fabric for heat-sensitive stencil printing according to claim 1, wherein the tensile elastic modulus is 0.15 N / mm or more.