JPH09300847A - Base paper for thermal stencil printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide base paper for thermal stencil printing in which printing clearness and carrier properties are excellent. SOLUTION: The base paper for thermal stencil printing is constituted by bonding a polyester film to a polyester nonwoven fabric without using an adhesive. In this case, orientation parameters of the film part and the nonwoven fabric part which are obtained by the laser Raman spectroscopic method are 3-10. A thin layer containing at least one kind selected from among an amino- modified silicone oil, a carboxyl-modified silicone oil, an alcohol-modified silicone oil and an epoxy-modified silicone oil as a main body is provided on one side to be brought into contact with a thermal head in the film.

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 a thermal head or the like, and more particularly to a heat-sensitive stencil sheet having excellent printing clarity and excellent transportability.

[0002]

2. Description of the Related Art Conventionally, as heat-sensitive stencil printing base paper (hereinafter simply referred to as base paper), thermoplastic resin films such as polyester films and vinylidene chloride films have been used.
There is known a structure in which a porous support made of natural fiber, chemical fiber or synthetic fiber or a thin paper, nonwoven fabric, gauze or the like obtained by mixing them is bonded with an adhesive (for example, see Japanese Patent Application Laid-Open No. SHO 51-51). No. 2513, JP-A-57
182495).

[0003] However, the conventional base paper has the drawbacks that white spots occur in solid black portions and fine characters are blurred. It is considered that the cause of these poor print clarity is that the permeation of the ink is hindered by the adhesive bonding the film and the porous support.

Various proposals have been made so far in order to improve the drawbacks caused by these adhesives. For example, JP-A-58-147396, JP-A-4-23279
In Japanese Patent Laid-Open No. 0-44, a method of reducing the amount of adhesive used as much as possible and a method of using no adhesive are disclosed in
No. 212891 discloses a base paper in which synthetic fibers are sprinkled on one surface of a thermoplastic resin film and thermocompression bonded. However, it has been found that these methods have a problem in that the adhesive strength is insufficient, or that when sufficient adhesive strength is to be obtained, sufficient perforation does not occur and the print density does not increase.

Further, Japanese Patent Application Laid-Open No. Hei 6-305273 discloses that a base paper is obtained by co-drawing an undrawn polyester film and an undrawn polyester fiber. The base paper has sufficient adhesive strength without the use of an adhesive, but wrinkles are likely to occur during transport, and it is easy to fuse with the thermal head during perforation, which limits the improvement of printability.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a base paper having high definition, high image quality printability and excellent transportability, which cannot be realized by the conventional base paper.

[0007]

Means for Solving the Problems The inventors of the present invention have made extensive studies in view of the above-mentioned problems, and as a result, in a heat-sensitive stencil printing base paper obtained by adhering a polyester film and a polyester non-woven fabric without an adhesive, laser Raman The orientation parameter of the film portion and the non-woven fabric portion obtained by the spectroscopic method is 3 to 10, and the amino-modified silicone oil, carboxyl-modified silicone oil, alcohol-modified silicone oil and epoxy-modified one surface of the film to be brought into contact with the thermal head. A heat-sensitive stencil printing base paper comprising a thin layer mainly composed of at least one selected from silicone oils.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The polyesters used in the polyester film and the polyester nonwoven fabric in the present invention are mainly composed of aromatic dicarboxylic acid, aliphatic dicarboxylic acid or alicyclic dicarboxylic acid and diol. . Here, as the aromatic dicarboxylic acid component, for example, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′- Examples thereof include diphenyl dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, and 4,4'-diphenyl sulfone dicarboxylic acid. Of these, terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid are preferably used. it can. Examples of the aliphatic dicarboxylic acid component include succinic acid, adipic acid,
Suberic acid, sebacic acid, dodecanedioic acid, eicosandioic acid, dimer acid and the like can be used, and among them, adipic acid and sebacic acid can be preferably used. Further, as the alicyclic dicarboxylic acid component, for example,
1,4-cyclohexanedicarboxylic acid or the like can be used. These acid components may be used alone or in combination of two or more, and further, an oxy acid such as hydroxybenzoic acid may be partially copolymerized. Examples of the diol component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol,
2,2-bis (4-hydroxyethoxyphenyl) propane or the like can be used. Among them, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, and 1,4-cyclohexanedimethanol are 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 preferably polyethylene terephthalate, a copolymer of ethylene terephthalate and ethylene isophthalate, polyethylene-2,6-naphthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polyhexahexene. Methylene-2,6-naphthalate, copolymer of butylene terephthalate and ethylene terephthalate, copolymer of butylene terephthalate and hexamethylene terephthalate, copolymer of hexamethylene terephthalate and 1,4-cyclohexane dimethylene terephthalate, ethylene A copolymer of terephthalate and ethylene-2,6-naphthalate can be used. Particularly preferably in order to improve the perforation sensitivity, a copolymer of ethylene terephthalate and ethylene isophthalate, polyhexamethylene terephthalate,
Hexamethylene terephthalate and 1,4-cyclohexane dimethylene terephthalate, a copolymer of ethylene terephthalate and ethylene-2,6-naphthalate, or the like can be used.

The polyester used in the polyester nonwoven fabric of the present invention is preferably polyethylene terephthalate, polyethylene-2,6-naphthalate,
Poly-1,4-cyclohexane dimethylene terephthalate, a copolymer of ethylene terephthalate and ethylene isophthalate, or the like can be used. From the viewpoint of thermal dimensional stability during perforation, polyethylene terephthalate, polyethylene naphthalate and the like can be used particularly preferably.

The polyester in the present invention can be manufactured 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, alkali metal, alkaline earth metal, manganese, cobalt, zinc, antimony, germanium,
A titanium compound or the like can also be used. Further, a phosphorus compound can be used as a heat stabilizer.

If necessary, the polyester of the present invention may contain a flame retardant, an antioxidant, an ultraviolet absorber, a pigment, a dye, a defoaming agent such as polysiloxane, and the like.

Further, various slipperiness imparting methods can be adopted. For example, clay, mica, titanium oxide,
Calcium carbonate, kaolin, talc, inorganic particles such as wet or dry silica, alumina, zirconia, acrylic acid, a method of blending organic particles having styrene or the like as a constituent component, depositing a catalyst or the like added during the polyester polymerization reaction, There are a so-called internal particle method and a method of applying a surfactant.

The polyester non-woven fabric constituting the base paper in the present invention is obtained by stretching the non-stretched non-oriented non-woven fabric obtained by a direct melt spinning method such as a melt blow method or a spun bond method using the above polyester. It is a thing. The intrinsic viscosity of the polyester used is preferably 0.3 or more, more preferably 0.4 or more, and particularly preferably 0.5 or more.

In the melt-blowing method, the unstretched non-woven fabric is blown with hot air from the periphery of the die when the molten polyester polymer is ejected from the die, and the extruded polymer is made finer by the hot air and then placed at an appropriate position. It is sprayed and collected on the above-mentioned net conveyor, and a web is formed to be manufactured. Since the web is sucked together with the hot air by the suction device provided on the net conveyor, the individual fibers are collected before being 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 polymer discharge amount, hot air temperature, hot air flow rate, conveyor moving speed, etc., it is possible to arbitrarily set the fiber orientation of the unstretched nonwoven fabric, the web areal weight and the single yarn fiber diameter. The fiber spun by the melt blow method is finely pulverized by the pressure of hot air and solidified in a non-oriented or low-oriented state is particularly preferably used. The fibers constituting the undrawn nonwoven fabric are preferably substantially continuous. Further, the polymer discharged from the die is rapidly cooled from a molten state to a room temperature atmosphere, so that it is almost amorphous.
It can be solidified in a low crystalline state.

Similarly, in the spunbond method, the unstretched non-woven fabric is drawn by pulling the polymer discharged from the die with an air ejector, colliding the obtained filament with a collision plate to open the fiber, and collecting it in a conveyor shape. Manufactured by forming a web. The basis weight of the web can be arbitrarily set by appropriately setting the polymer discharge amount and the conveyor speed. 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.
A web having a low degree of molecular orientation can be obtained by reducing the spinning speed by reducing the pressure and the flow rate. Further, by adjusting the cooling rate of the discharged polymer, a web having low crystallinity can be obtained. When produced by the spunbond method, the unstretched polyester nonwoven fabric used to obtain the base paper of the present invention is preferably spun at a spinning speed of 2500 m / min or less, more preferably 2000 m / min.
Min or less, particularly preferably 1500 m / min or less.

The crystallinity of the unstretched polyester nonwoven fabric used in the present invention is preferably 20% or less, more preferably 10% or less, and particularly preferably 5% or less.

The unstretched polyester nonwoven fabric used in the present invention is most preferably non-oriented, but it is more preferred that the unstretched polyester nonwoven fabric has a low draw ratio even when stretched, and a low degree of orientation. The birefringence (Δn) is preferably 0.03 or less, more preferably 0.02 or less, and particularly preferably 0.01 or less.

The base paper of the present invention is preferably obtained by stacking an unstretched film and the above unstretched nonwoven fabric and biaxially stretching them. The method for forming an unstretched film using polyester is based on the following method. For example, an unstretched film can be produced by extruding polyester onto a cast drum by the 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 intrinsic viscosity of the polyester used for the polyester film is preferably 0.5
Or more, more preferably 0.53 or more, and particularly preferably 0.55 or more.

The polyester film and the polyester non-woven fabric according to the present invention are bonded together without an adhesive. Adhesion is the above unstretched polyester nonwoven fabric,
Most preferably, the unstretched polyester film obtained by extrusion casting and the pre-stage of the longitudinal stretching step are performed. The heat-bonding temperature is preferably between the glass transition temperature (Tg) and melting point (Tm) of the polyester film, more preferably between Tg and the cold crystallization temperature (Tcc), particularly preferably Tg + 10. ℃ ~ Tg + 50 ℃
Range.

The method of co-stretching is not particularly limited, but biaxial stretching is preferred, and either sequential biaxial stretching method or simultaneous biaxial stretching method may be used. In the case of the sequential biaxial stretching method, stretching is generally performed in the longitudinal direction and then in the transverse 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 may be appropriately determined depending on the type of the polyester film polymer used, the sensitivity required for the base paper, etc., but is preferably 2 to 8 times in each of the length and width, more preferably 3 to 8 times. Double is appropriate. After biaxial stretching, the film may be stretched longitudinally or horizontally, or vertically and horizontally again.

After that, the biaxially stretched base paper of the present invention may be heat treated. The heat treatment temperature is not particularly limited and may be appropriately determined depending on the type of film polymer or non-woven fabric polymer used, but is preferably 80 to 240.
C., more preferably 80 to 170.degree. C., more preferably 90 to 150.degree. C., and the time is suitably 0.5 to 60 seconds.

The base paper obtained by the heat treatment is once cooled to room temperature and then at a relatively low temperature of 40 to 90 ° C. for 5 minutes.
It can be aged for about a week to a minute. When such aging is employed, curling and wrinkles are less likely to occur during storage of the base paper or in the printing press, and it is particularly preferable.

In the present invention, the orientation parameter of the film portion and the non-woven fabric portion is 3 to 10. Both are preferably 3.5 to 8 or more, and more preferably both are 4 or more.
~ 7. If the film portion is less than 3 or the nonwoven fabric portion is more than 10, the perforation is insufficient and the printing sharpness is reduced. Further, if the film portion exceeds 10 or the nonwoven fabric portion is less than 3, wrinkles are likely to occur and the transportability is deteriorated.

The orientation parameter referred to in the present invention is determined by laser Raman spectroscopy. For the film portion, the base paper is embedded in PMMA resin and wet-polished to form a cross section perpendicular to the longitudinal or width direction of the film.
bin Yvon / Atago Bussan "Ramanor" U-
1000I (light source: NEC GLG3300 Ar ⁺ laser 514.5 nm, microscope: Olympus BH
-Type 2 objective lens × 100) was used to irradiate a laser beam perpendicularly to the cross section, and the Raman spectrum of the laser beam polarized in the plane direction of the film and the laser beam polarized in the thickness direction of the film was 1615 cm ^{−. When} the peak intensities of ^one band are I and IND, the ratio I / IND is the orientation parameter of the film.
The larger the value of this orientation parameter, the higher the degree of orientation. In the case of fiber, it is not necessary to form a cross section,
Using the above device, a laser beam is radiated perpendicularly to the fiber axis, and the peak of the Raman spectrum at 1615 cm ⁻¹ band due to the laser beam polarized in the length direction of the fiber and the laser beam polarized in the diameter direction of the fiber When the strengths are I and IND, respectively, the ratio I / IND is the fiber orientation parameter.

In the present invention, in order to bond the polyester film and the polyester non-woven fabric without the interposition of an adhesive so that the orientation parameters fall within the above range, the polymer species and the degree of polymerization of the film and the non-woven fabric,
This is achieved by appropriately adjusting the degree of orientation of the unstretched film and the unstretched nonwoven fabric, the respective temperatures during co-stretching, the stretching ratio, and the heat treatment temperature. It is preferable that the unstretched film and the unstretched non-woven fabric have similar stretching behavior, but even when the difference in the proper stretching temperature is large, for example, in the preheating stage before longitudinal stretching, the unstretched film portion, the unstretched nonwoven fabric portion is preheated. If different infrared heaters are used, or if they are contacted with single or multiple rolls for preheating, they can be heated by providing a difference in the temperature of the rolls where the unstretched film part and the unstretched nonwoven fabric part are in direct contact. It is possible to achieve high uniaxial orientation of the film portion and the non-woven fabric portion by carrying out the above and stretching after combining these. Further, in the case of transverse stretching with a tenter, a method of providing a difference in temperature of hot air between the film surface side and the non-woven fabric surface side in the preheating stage before stretching can be adopted.

The area fraction of the open pores obtained by directly observing the support surface of the base paper of the present invention by the bright field transmission method of an optical microscope is preferably 3 to 80%, more preferably 5 to 50%, and particularly It is preferably 10 to 30%. Further, when the opening is regarded as a circle, the average value of the equivalent circle diameter is preferably 5
˜100 μm, more preferably 10 to 60 μm, and particularly preferably 10 to 30 μm.

The fiber basis weight of the polyester nonwoven fabric constituting the base paper of the present invention is preferably 1 to 30 g / m ^2, more preferably 2 to 20 g / m ^2, particularly preferably is 3~16g / m ² .

The average fiber diameter of the single yarn constituting the polyester nonwoven fabric of the present invention is 1 to 20 μm, preferably 2 to 15 μm.
m, more preferably 3 to 12 μm.

The crystallinity of the polyester nonwoven fabric of the present invention is preferably 15% or more, more preferably 20%.
% Or more, particularly preferably 25% or more.

The polyester film constituting the base paper of the present invention is preferably a biaxially stretched film and has a thickness of
The thickness is appropriately determined depending on the sensitivity required for the base paper, etc., but is preferably 0.1 to 5 μm, and more preferably 0.
It is 1 to 4 μm, more preferably 0.1 to 3 μm.

The polyester film constituting the base paper of the present invention preferably has a melting point of 240 ° C. or lower, more preferably 230 ° C. or lower, still more preferably 220 ° C. or lower. Also, the crystal melting energy (ΔHu) is 3 to
It is preferably 11 cal / g, more preferably 5
~ 11 cal / g.

The melting point (Tm1) of the polyester film and the melting point (Tm) of the polyester fiber constituting the base paper of the present invention.
2) is preferably Tm1 ≤ Tm2, more preferably the temperature difference is 5 ° C or more, particularly preferably 10 ° C or more.

The peel strength between the polyester film constituting the base paper of the present invention and the porous support is preferably 3 g / c.
m or more, more preferably 5 g / cm or more, and particularly preferably 10 g / cm or more.

The base paper of the present invention has an amino-modified silicone oil on one side to be brought into contact with the thermal head of the film.
A thin layer containing at least one selected from carboxylic acid-modified silicone oil, alcohol-modified silicone oil and epoxy-modified silicone oil is provided. Preferably, a thin layer mainly containing at least one selected from amino-modified silicone oil and carboxylic acid-modified silicone oil is provided. Amino-modified silicone oil, carboxyl-modified silicone oil, alcohol-modified silicone oil, and epoxy-modified silicone oil are those in which an organic group having an amino group, a carboxyl group, a hydroxyl group, and an epoxy group is bonded to the side chain or end of a polysiloxane chain, respectively. Is. If the silicone oil These modified silicone oil is not particularly limited, JIS-K-2283 is compliant measured viscosity, preferably at 25 ° C. 0.1 to 10 m ² /
s. As the other component constituting the thin layer on the surface of the film, any component may be used as long as it does not inhibit the effect of the modified silicone oil, but silicone resin, fluorine resin, surfactant, antistatic agent, heat-resistant agent, Not only antioxidants, organic particles, inorganic particles, pigments, dispersion aids, preservatives, antifoaming agents, but also other silicone oils can be mentioned. The amount of the modified silicone oil was 0.
Preferably 001~0.5g / m ^2, particularly preferably from 0.05 to 0.3 g / m ^2.

In the present invention, the thickness of the thin layer mainly composed of the modified silicone oil is preferably 0.005 μm or more and 0.4 μm or less, more preferably 0.01 μm or more and 0.1 μm or less.
It is 4 μm or less. When the thickness of the release agent layer is 0.4 μm or less, the running property at the time of punching is good and the contamination of the head is small.

When a thin layer mainly composed of modified silicone is provided in the base paper of the present invention, the coating liquid is preferably a coating liquid dissolved, emulsified or suspended in water from the viewpoint of explosion proof and environmental pollution.

The thin layer mainly composed of the modified silicone may be applied 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 coating method is not particularly limited, but it is preferable to use a roll coater, a gravure coater, a reverse coater, a bar coater or the like.

If necessary, the coated surface may be subjected to corona discharge treatment in air or various other atmospheres before providing the thin layer mainly composed of the modified silicone.

[0040]

[Characteristics measurement method]

(1) Orientation parameter The orientation parameter was determined by laser Raman spectroscopy. For the film part, embed the base paper in PMMA resin,
Wet polishing is performed to form a cross section perpendicular to the longitudinal or width direction of the film. For example, Jobin Yvon / Atago Bussan “Ramanor” U-1000I (light source: NEC G
LG3300 Ar ⁺ laser 514.5 nm, microscope: Olympus BH-2 type objective lens × 100)
Laser light is radiated perpendicularly to the cross section, and the peak intensity of the 1615 cm ⁻¹ band of the Raman spectrum by the laser light polarized in the plane direction of the film and the laser light polarized in the thickness direction of the film is I And IND, the ratio I / IND was used as the orientation parameter of the film.

In the case of a non-woven fabric, it is not necessary to form a cross section, and laser light is radiated perpendicularly to the fiber axis by using the above-mentioned device, and laser light polarized in the length direction of the fiber and diameter direction of the fiber are used. 1615cm Raman spectra of by laser light polarized in ^- when ^a peak intensity of the band is I and IND, respectively, and the ratio I / IND and orientation parameters of the nonwoven fabric.

(2) Melting point (Tm, ° C) Differential scanning calorimeter RDC220 manufactured by Seiko Instruments Inc.
Using a mold, a 5 mg sample was collected, and the temperature was
It was determined from the peak temperature of the endothermic curve when the temperature was raised at a rate of ° C./min.

(3) Crystal melting energy (ΔHu) Differential scanning calorimeter RDC220 manufactured by Seiko Electronic Industry Co., Ltd.
It is determined from the area at the time of melting using a mold. 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. I under the same DSC conditions
n (indium) is measured, and this area (b) is 6.8c
It is calculated by the following formula as al / g.

6.8 × a / b = ΔHu (cal / g)

(4) Fiber diameter (μm) 10 photographs were taken at arbitrary 10 points on the base paper with an electron microscope at a magnification of 2000, and 15 photographs were taken per photograph.
The diameter of each fiber was measured, and this was carried out for 10 photographs to measure a total of 150 fiber diameters.

(5) Fiber areal weight (g / m ² ) A piece of base paper 20 cm × 20 cm was taken and its weight was measured and converted into weight per m ² .

(6) Intrinsic viscosity [η] 0.1 ± 0.00 after drying the sample at 105 ° C for 20 minutes
5 g is weighed, and 160 ° C. × 1 in o-chlorophenol.
It was dissolved by stirring for 5 minutes. After cooling, the viscosity at 25 ° C. was measured and determined using a Yamatrabotik AVM-10S type automatic viscosity meter.

(7) Crystallinity (%) A sample was placed in a density gradient tube made of a mixed solution of n-heptane and carbon tetrachloride, and the value was read after 10 hours or more to determine the density. A density of 0% crystallinity is 1.335 g / c
m ³ , a density of 100% crystallinity is 1.455 g / cm ³
The crystallinity of the sample was calculated.

(8) Birefringence (Δn) Retardation was calculated by a Berek convensor method with a polarizing microscope using a sodium lamp as a light source and immersing the sample in α-promnaphthalene.

(9) Area Fraction (%) of Openings of Support Material The support surface of the base paper was directly observed by a bright-field transmission method using an optical microscope, and a Hi-Vision compatible image analyzer manufactured by Pierce Co., Ltd. was used. Then, the area ratio of the aperture was determined at a monitor magnification of 240 times. The area fraction was calculated at 10 arbitrary measurement points and expressed as an average value.

(10) Mean value (μm) of the equivalent circular diameter of the aperture of the support The surface of the support of the base paper was directly observed by the bright-field transmission method of an optical microscope, and an image analysis device compatible with Hi-Vision manufactured by Pierce Co., Ltd. Using a monitor with a monitor magnification of 240 times, black and white reversal processing,
The equivalent circular diameter of the opening was measured, and the average value was determined. Measurement was performed at 10 arbitrary measurement points, and the average value was shown.

(11) Peel strength (g / cm) Cellophane tape was attached to the film surface to reinforce, and the peel strength between the film and the porous support was measured according to JIS-K-6854.
It was measured by a 180-degree peeling test method according to.

(12) Evaluation of printability The prepared base paper was supplied to a printing machine "Lisograph" GR275 manufactured by Riso Kagaku Kogyo Co., Ltd., and a black solid of 10 mm on a side (■) was printed on A4 size by a thermal head type plate making method. A master was created by making a grid on the entire surface. The energy supplied to the thermal head was 30 μJ per dot. Printing was performed using the master, and the Macbeth density of printed matter and the presence or absence of white spots were evaluated by visual judgment.

The determination of white spots is ⊚ when there is no white spots, ◯ when there is a white spot in a small part of the solid black portion, and Δ when there is a white spot in less than half of the solid black portion. The white solid part in each black solid part was marked with x.

(13) Evaluation of transportability The prepared base paper was supplied to a printing machine "Lisograph" GR275 manufactured by Riso Kagaku Kogyo Co., Ltd. to make a plate, and the presence or absence of wrinkles in the base paper on the plate cylinder was visually judged to determine It was evaluated as.

When the base paper on the plate cylinder has no wrinkles at all, ⊚, and when wrinkles of 1 mm or less occur, ○, 1 to
The one in which wrinkles of 5 mm occurred was rated as Δ, and the one in which wrinkles of 5 mm or more occurred was rated as x.

[0057]

【Example】

Example 1 (Making of unstretched polyester nonwoven fabric) Pore diameter 0.35 m
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 0.48) was spun by a melt blow method at 80 ° C. and a discharge rate of 30 g / min, and fibers were collected and wound on a net conveyor at a collection distance of 15 cm. . At this time, the amount of hot air blown from around the spinneret was set to 2.6 Nm ³ / min, and the temperature of the web immediately below the spinneret was set to 87 ° C. by the suction device provided on the net conveyor. The fiber weight of the unstretched nonwoven fabric is 140 g /
m ² , the average fiber diameter was 8.7 μm, the crystallinity was 1%, and the birefringence (Δn) was 0.003.

(Film formation) Next, an ethylene terephthalate-ethylene isophthalate copolymer containing 0.4% by weight of silica having an average particle diameter of 1.5 μm (isophthalic acid 25
Mol% copolymerization, melting point 195 ° C., intrinsic viscosity 0.72) was pre-crystallized in an oven at 120 ° C., then dried under reduced pressure at 150 ° C. for 3 hours in a rotary dryer, and an extruder with a screw diameter of 40 mm was used. , T-die mouthpiece extruded at a temperature of 270 ° C, cast on a cooling drum with a diameter of 300 mm to a thickness of 13 μm
Was produced.

The non-woven fabric is laminated on the unstretched film to form a roll group consisting of five rolls in which the rotation directions of adjacent rolls are opposite to each other and a sixth roll rotating in the same direction as the fifth roll. The film surface of the first roll and the non-woven fabric surface of the second roll were passed through the fifth roll in a plow shape so that the non-woven fabric surface of the sixth roll was in contact with the non-woven fabric face of the second roll. At this time, the first roll and the second roll are metal rolls whose surfaces are plated with chrome, the third to sixth rolls are rolls coated with silicone rubber, and the surface temperature of the rolls is 83 ℃,
The second roll is 83 ℃ and the third roll is 90
℃, the fourth roll is 87 ℃, the fifth roll is 9
The temperature was 3 ° C and the sixth roll was 25 ° C. Further, the peripheral speeds of the first to fifth rolls were the same, and the peripheral speed difference was provided between the fifth and sixth rolls, whereby the film was stretched 3.5 times in the longitudinal direction.

Next, an aqueous dispersion of amino-modified silene oil (concentration: 2%) was applied onto the obtained laminated sheet using a metering bar so that the application thickness was 9 μm.

Further, it was sent to a tenter type horizontal stretching machine,
Heated to 95 ° C with hot air and stretched 4.0 times in the width direction,
Heat treatment was performed at 120 ° C. for 10 seconds to prepare a heat-sensitive stencil sheet. The orientation parameters of the obtained base paper were 5.5 for the film part, 4.8 for the non-woven fabric part, and 10 g / unit for the non-woven fabric weight.
m ² , and the average fiber diameter was 5 μm. The film alone had a thickness of 0.9 μm, a melting point of 195 ° C., and a crystal melting energy of 5.9 cal / g. The amount of amino-modified silicone oil applied was 0.04 g / m ² .

(Evaluation Results) As summarized in Table 1, Table 2 and Table 3, when the printability was evaluated using the finally obtained base paper, the printed matter printed using this base paper was The density of the black solid portion was high, there were no white spots, and no wrinkles occurred, which was good.

Comparative Example 1 The unstretched polyester non-woven fabric obtained in Example 1 alone,
A biaxially stretched polyester nonwoven fabric was obtained in the same manner as in the film formation of Example 1. The orientation parameter of the non-woven fabric was 4.8, the basis weight was 10 g / m ² , and the average fiber diameter was 5 μm.
A biaxially stretched polyester film was obtained in the same manner as in the film formation of Example 1, except that unstretched nonwoven fabrics were not overlaid and aminosilicone oil was not applied. The film had a thickness of 0.9 μm, a melting point of 190 ° C., and a crystal melting energy of 5.9 cal / g.

The above biaxially stretched polyester nonwoven fabric and 2
The axially stretched polyester film was heat-bonded with a nip roll at a temperature of 100 ° C. and a linear pressure of 30 N / cm, but peeling occurred between the film and the nonwoven fabric, and sufficient adhesive force could not be obtained.

Comparative Examples 2 and 3 A laminate comprising a polyester film and a polyester non-woven fabric was prepared in the same manner as in Comparative Example 1 except that the temperatures of the nip rolls were 150 ° C. and 190 ° C., and 0.04 g of amino-modified silicone oil was then added. The base paper was obtained by coating so as to be / m ² .

The characteristics of the obtained base paper are shown in Tables 1, 2 and 3. The evaluation results are also shown, but the print clarity or transportability was poor.

Comparative Example 4 A base paper was obtained in the same manner as in Example 1 except that the amino-modified silicone oil was not applied. The evaluation results are summarized in Table 1, Table 2 and Table 3, and it can be seen that wrinkles occur and the transportability deteriorates when the amino-modified silicone oil is not applied.

Comparative Example 5 A base paper was obtained in the same manner as in Example 1 except that the ethylene terephthalate-ethylene isophthalate copolymer had an intrinsic viscosity of 0.61. The evaluation results are summarized in Table 1, Table 2 and Table 3, but it can be seen that the printing sharpness decreases.

Comparative Example 6 A base paper was obtained in the same manner as in Example 1 except that the temperatures of the rolls used for stretching in the longitudinal direction were all set to 93 ° C. Table 1,
The evaluation results are summarized in Tables 2 and 3, and it can be seen that the print clarity is reduced.

Examples 2 to 4 and Comparative Example 7 The same as Example 1 except that carboxyl-modified silicone oil, alcohol-modified silicone oil, epoxy-modified silicone oil and dimethyl silicone oil were applied in place of the amino-modified silicone oil. I got the base paper. The evaluation results are summarized in Table 1, Table 2 and Table 3. When the modified silicone oil of the present invention is applied, the printing sharpness and transportability are good, while the dimethyl silicone oil is printed. It can be seen that sharpness and transportability are reduced.

Example 5 (Fabrication of non-stretched polyester non-woven fabric) Pore size 0.35 m
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 0.55) was spun by a melt blow method at 85 ° C. and a discharge rate of 30 g / min, and fibers were collected and wound on a net conveyor at a collection distance of 15 cm. . At this time, the amount of hot air blown from around the die was set to 2.8 Nm ³ / min, and the temperature of the web immediately below the die was set to 87 ° C. by the suction device provided on the net conveyor. The fiber basis weight of the unstretched nonwoven fabric is 120 g /
m ² , average fiber diameter was 9.5 μm, crystallinity was 2%, and birefringence (Δn) was 0.004.

(Film Forming) Next, an ethylene terephthalate-ethylene isophthalate copolymer (isophthalic acid 14%) containing 0.4% by weight of silica having an average particle diameter of 1.5 μm was prepared.
Mol% copolymerization, melting point 225 ° C., intrinsic viscosity 0.61) is pre-dried at 120 ° C. in an oven and then 175 in a rotary dryer.
At 275 ° C. using a 40 mm screw diameter extruder.
An unstretched film having a thickness of 13 μm was formed by casting on a cooling drum having a thickness of 13 mm.

On the unstretched film, the above-mentioned non-woven fabric was laminated, and a roll group consisting of five rolls in which the rotation directions of adjacent rolls were opposite and a sixth roll rotating in the same direction as the fifth roll were formed. The film surface of the first roll and the non-woven fabric surface of the second roll were passed through the fifth roll in a plow shape so that the non-woven fabric surface of the sixth roll was in contact with the non-woven fabric face of the second roll. At this time, the first roll and the second roll are metal rolls whose surfaces are plated with chrome, the third to sixth rolls are rolls coated with silicone rubber, and the surface temperature of the rolls is 83 ℃,
The second roll is 83 ℃, the third roll is 92
℃, the fourth roll is 89 ℃, the fifth roll is 9
The temperature was 6 ° C and the sixth roll was 25 ° C. Further, the peripheral speeds of the first to fifth rolls were the same, and the peripheral speed difference was provided between the fifth and sixth rolls, whereby the film was stretched 3.5 times in the longitudinal direction.

Next, an aqueous dispersion of amino-modified silene oil (concentration: 2%) was applied onto the obtained laminated sheet using a metalling bar so that the application thickness was 9 μ.

Further, it was sent to a tenter type horizontal stretching machine,
Heated to 97 ° C with hot air, stretched 4.0 times in the width direction,
Heat treatment was performed at 120 ° C. for 10 seconds to prepare a heat-sensitive stencil sheet. The orientation parameters of the obtained base paper were 5.8 for the film portion, 4.9 for the non-woven fabric portion, and 9 g / m for the non-woven fabric weight.
² , the average fiber diameter was 5 μm. The thickness of the film alone is 0.9 μm, and the crystal melting energy is 7.9 ca.
1 / g. The amount of amino-modified silicone oil applied was 0.04 g / m ² .

(Evaluation Results) As shown in Table 1, Table 2 and Table 3, printability was evaluated using the finally obtained base paper. The printed matter printed using this base paper was There were no white spots, and no wrinkles occurred, which was good.

Example 6 (Fabrication of unstretched polyester non-woven fabric) Pore diameter 0.35 m
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 0.61) was spun by a melt blow method at 90 ° C. and a discharge rate of 30 g / min, and fibers were collected and wound on a net conveyor at a collection distance of 15 cm. . At this time, the amount of hot air blown from around the die was set to 2.9 Nm ³ / min, and the temperature of the web immediately below the die was set to 87 ° C. by the suction device provided on the net conveyor. The fiber basis weight of the unstretched nonwoven fabric is 120 g /
m ² , average fiber diameter was 9.4 μm, crystallinity was 1%, and birefringence (Δn) was 0.004.

(Film formation) Next, an ethylene terephthalate-ethylene-2,6-naphthalate copolymer (2,6-) containing 0.4% by weight of silica having an average particle diameter of 1.5 μm.
Naphthalene dicarboxylic acid 30 mol% copolymerization, melting point 180
C., intrinsic viscosity 0.61) is pre-dried at 110.degree. C., and dried under reduced pressure at 140.degree. C. for 4 hours in a rotary dryer to give a screw diameter of 4
It was extruded at a T-die die temperature of 270 ° C. using an 0 mm extruder and cast on a cooling drum having a diameter of 300 mm to prepare an unstretched film having a thickness of 13 μm.

On the unstretched film, the above-mentioned non-woven fabric was superposed, and a roll group consisting of five rolls in which the rotation directions of adjacent rolls were opposite and a sixth roll rotating in the same direction as the fifth roll were formed. The film surface of the first roll and the non-woven fabric surface of the second roll were passed through the fifth roll in a plow shape so that the non-woven fabric surface of the sixth roll was in contact with the non-woven fabric face of the second roll. At this time, the first roll and the second roll are metal rolls whose surfaces are chrome-plated, the third to sixth rolls are rolls coated with silicone rubber, and the surface temperature of the rolls is 85 ℃,
The second roll is 85 ℃, the third roll is 95
℃, the fourth roll is 89 ℃, the fifth roll is 9
The temperature was 8 ° C and the sixth roll was 25 ° C. Further, the peripheral speeds of the first to fifth rolls were the same, and the peripheral speed difference was provided between the fifth and sixth rolls, whereby the film was stretched 3.5 times in the longitudinal direction.

Then, an aqueous dispersion of amino-modified silene oil (concentration: 2%) was applied onto the obtained laminated sheet using a metering bar so that the application thickness was 9 μm.

Further, it was fed into a tenter type horizontal stretching machine,
It was heated to 100 ° C. with hot air, stretched 4.0 times in the width direction, and heat-treated at 140 ° C. for 10 seconds to prepare a heat-sensitive stencil sheet. The orientation parameter of the obtained base paper was 5.2 for the film part, 5.3 for the non-woven fabric part, and 9 g for the non-woven fabric weight.
/ M ² and the average fiber diameter was 5 μm. The thickness of the film alone is 0.9 μm, and the crystal melting energy is 5.4.
It was cal / g. The amount of amino-modified silicone oil applied was 0.04 g / m ² .

(Evaluation Results) As summarized in Table 1, Table 2 and Table 3, when the printability of the finally obtained base paper was evaluated, the printed matter printed using this base paper was The density of the black solid portion was high, there were no white spots, and no wrinkles occurred, which was good.

Comparative Example 8 A base paper was obtained in the same manner as in Example 6 except that the intrinsic viscosity of polyethylene terephthalate as the raw material for the non-woven fabric was 0.48. The evaluation results are shown in Table 1, Table 2 and Table 3, but it can be seen that the transportability is lowered.

Example 7 (Fabrication of unstretched polyester non-woven fabric) Pore diameter 0.35 m
m, using a rectangular spinneret having 100 holes and a spinneret temperature of 2
An ethylene terephthalate-ethylene isophthalate copolymer (isophthalic acid 3 mol% copolymerization, melting point 248 ° C., intrinsic viscosity 0.61) was spun by a melt-blowing method at 75 ° C. and a discharge rate of 30 g / min, and a collecting distance was 15 cm. The fibers were collected on a net conveyor and wound up. At this time, the amount of hot air blown from around the spinneret was set to 2.4 Nm ³ / min, and the temperature of the web immediately below the spinneret was set to 84 ° C. by the suction device provided on the net conveyor. The fiber weight of the unstretched non-woven fabric is 150 g
/ M ² , the average fiber diameter was 9.4 μm, the crystallinity was 1%, and the birefringence (Δn) was 0.004.

(Film Forming) Next, an ethylene terephthalate-ethylene isophthalate copolymer containing 0.4% by weight of silica having an average particle diameter of 1.5 μm (isophthalic acid 25
Mol% copolymerization, melting point 195 ° C., intrinsic viscosity 0.72) was crystallized in an oven at 120 ° C., and then dried under reduced pressure at 150 ° C. for 3 hours in a rotary dryer, using an extruder with a screw diameter of 40 mm. , T-die mouthpiece extruded at a temperature of 270 ° C, cast on a cooling drum with a diameter of 300 mm to a thickness of 13 μm
Was produced.

On the unstretched film, the above-mentioned non-woven fabric was laminated, and a roll group consisting of five rolls in which the rotation directions of adjacent rolls were opposite and a sixth roll rotating in the same direction as the fifth roll were formed. The film surface of the first roll and the non-woven fabric surface of the second roll were passed through the fifth roll in a plow shape so that the non-woven fabric surface of the sixth roll was in contact with the non-woven fabric face of the second roll. At this time, the first roll and the second roll are metal rolls whose surfaces are chrome-plated, the third to sixth rolls are rolls coated with silicone rubber, and the surface temperature of the rolls is 81 ℃,
The second roll is 81 ° C and the third roll is 87
℃, the fourth roll is 83 ℃, the fifth roll is 8
The temperature was 8 ° C and the sixth roll was 25 ° C. Further, the peripheral speeds of the first to fifth rolls were the same, and the peripheral speed difference was provided between the fifth and sixth rolls, whereby the film was stretched 3.5 times in the longitudinal direction.

Then, an aqueous dispersion of amino-modified silene oil (concentration: 2%) was applied onto the obtained laminated sheet using a metalling bar so that the application thickness was 9 μm.

Further, it was sent to a tenter type horizontal stretching machine,
Heated to 93 ° C. with hot air and stretched 4.0 times in the width direction,
Heat treatment was performed at 110 ° C. for 10 seconds to prepare a heat-sensitive stencil sheet. The orientation parameters of the obtained base paper were 5.9 for the film portion, 3.9 for the non-woven fabric portion, and 11 g / for the non-woven fabric weight.
m ² , and the average fiber diameter was 4 μm. The thickness of the film alone was 0.9 μm, the melting point was 195 ° C., and the crystal melting energy was 6.0 cal / g. The amount of amino-modified silicone oil applied was 0.04 g / m ² .

(Evaluation Results) As summarized in Table 1, Table 2 and Table 3, when the printability was evaluated using the base paper finally obtained, the printed matter printed using this base paper was The density of the black solid portion was high, there were no white spots, and no wrinkles occurred, which was good.

[0090]

[Table 1]

[Table 2]

[Table 3]

[0091]

According to the present invention, the above-mentioned structure is provided.
The following effects are obtained. That is, since there is no wrinkle in the transport system in the device during use and there is no fusion with the thermal head, the printed matter obtained by stencil printing using this base paper has printing sharpness and transport. Also excellent in sex.

Claims (1)

[Claims] 1. In a heat-sensitive stencil printing base paper obtained by adhering a polyester film and a polyester non-woven fabric without an adhesive, the orientation parameter of the film portion and the non-woven fabric portion determined by laser Raman spectroscopy is 3 to 10. And a thin layer mainly containing at least one selected from amino-modified silicone oil, carboxyl-modified silicone oil, alcohol-modified silicone oil and epoxy-modified silicone oil is provided on one surface of the film to be brought into contact with the thermal head. A heat-sensitive stencil printing base paper characterized by the following.