KR20020017509A - The thermal plate printing paper and its manufacturing method - Google Patents

Abstract

PURPOSE: Provided is a base paper for heat sensitive stencil printing with high sensitivity which is excellent in returning properties and printing durability and shows a high printing quality. Also, a method for producing such paper is provided. CONSTITUTION: The base paper for heat sensitive stencil printing comprises a synthetic resin film and a porous backing. The synthetic resin film is a two-layered co-extruded biaxial stretchable film having a top layer(A) and an inner layer(B), such as polyester resins which are prepared by reacting aromatic dicarbonic acid with alkyleneglycol. The ratio of a thickness of the top layer(A) to sum of thicknesses of the top layer(A) and the inner layer(B) is 0.01 or more and 0.1 or less. The difference between glass transition temperatures of the top layer(A) and the inner layer(B) is 20 deg.C or less. The base paper is produced by co-extruding material for the top layer and material for the inner layer(B) and laminating the co-extruded product over the porous backing.

Description

Thermal plate printing paper and its manufacturing method

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a thermosensitive plate printing paper which is perforated by heat generated by pulse irradiation of various xenon flash lamps or thermal heads, various laser beams, and the like, and a manufacturing method thereof.

The principle of the plate-making method of punching by heat generated by pulse irradiation of such a xenon flash lamp or thermal head, various laser beams, etc. is described in, for example, Japanese Patent Publication No. 7623/1966 Japanese Patent Laid-Open No. 103957/1980, Japanese Patent Laid-Open No. 143679/1984 and the like.

Conventionally, as a base paper used in such thermal plate printing, a base paper having a three-layer structure in which a film and a porous support are adhered by an adhesive or a two-layer structure in which a film and a porous support are laminated by heat is used. As the resin used for the paper film, a single layer film such as polyamide, polyethylene, polypropylene, soft polyolefin, polyvinylidene chloride, polyvinyl chloride, or polyester-based film is used, and as the porous support, thin paper and poly Ester silk paper, Teflon yarn and the like have been mainly used.

In general, thermal stencil printing reads originals on which letters and figures are recorded, and emits heat through xenon flash lamps or thermal heads to release images corresponding to the data values. The thermal stencil printing base on which an image produced by copying an image by a punching method is recorded is used as a printing original, and is fastened to a printing machine to perform high speed printing.

Since the thermal printing plate is punched using heat energy generated from a xenon flash lamp or a thermal head as printing energy, the film surface of the thermal printing plate is melted to form a xenon flash lamp or heat head ( Problems such as sticking frequently occur in thermal heads, etc., and such sticking phenomenon may cause problems such as deterioration of conveyability even when the printing disc is mounted on a printing drum, and deterioration of printing durability in high speed printing and mass printing. In some cases, as printing progresses, print quality may be degraded due to wear and deformation of the printing disc.

Therefore, in order to improve the high sensitivity and high resolution of the printing, a study on the improvement of the film such as lowering the melting energy (ΔHu) of the film so that the thin film of the thermal stencil printing paper and the perforation can be melted well even with low energy However, when the melting energy of the film is lowered, the problem of fusion of the film to the heat head occurs, so research on this is being actively conducted.

As a result of studies to solve the above problems, Japanese Patent Application Laid-Open No. 58-153697, Japanese Patent Laid-Open No. 61-40196, Japanese Patent Laid-Open No. 58-92595, Japanese Patent Laid-Open No. 60-97891, Japanese Patent Laid-Open 61 -182982 discloses a method of applying various lubricants and fusion inhibitors to the surface of the synthetic resin film in contact with the heat head, but a separate coating process is required because the anti-stick material must be formed on the film surface in contact with the heat head. There is a drawback that it is necessary to require a complicated step of performing permeation during film formation of the film.

In addition, the method of applying the fusion inhibitor to the surface of the film has a problem in that when the thermal printing plate is wound on the roller, the fusion inhibitor on the film is transferred to the substrate or the inside of the film, and the fusion preventive strength decreases over time.

Japanese Patent Laid-Open No. 2-55196 discloses a thermal stencil printing paper obtained by laminating an ink-permeable porous body and a heat-shrinkable synthetic resin film, wherein silicon is included in the substrate, and then the substrate and the film are adhered to each other. Although the method of adhering bonded as an adhesive is disclosed, in this case, there is a problem in that the adhesive strength is weak and the film is peeled off during printing and the printability is lowered.

In addition, Japanese Patent No. 3020622 uses alcohol-modified silicone oil as an anti-sticking agent to a synthetic resin film adhering to an ink-permeable porous body, and applies an anti-sticking solution using a cationic antistatic agent to remove the chargeability. The technique for preventing the fusion of the film is disclosed, but also in this case, it is difficult to punch the image due to the heat resistance of the silicone oil, and the cost increases due to the addition of the manufacturing process.

As can be seen from the prior art, a method of manufacturing a thermal stencil printing base is generally manufactured by laminating a porous support and a film with an adhesive. Since the thermal stencil printing base is manufactured by laminating, the adhesive force between the porous support and the film plays a very important role in the printing quality of the thermal stencil printing base.

As adhesives used for adhesion between the porous support and the film, various resins such as acrylic resin, vinyl acetate resin, saturated ester resin, rosin resin, and the like have been developed. When the adhesion between the support and the film is weak, the problem of separating the porous support and the film frequently occurs during high speed printing and mass printing, and when the adhesion between the porous support and the film becomes excessively strong, the curl of the thermal plate printing paper ( Curl) phenomenon is deepened and the perforation of letters is uneven during engraving, and when the plated printing disc is mounted on the printing drum, the thermal printing plate is wrinkled and damaged. Get mad.

In addition, in the lamination process, which is the most important step in the manufacturing process of the thermal stencil printing paper, the productivity of the thermal stencil printing base is greatly changed according to the running characteristics of the film, and in the case of poor film runability, uniform lamination is impossible. This causes a problem of greatly lowering productivity.

Therefore, in the process of laminating the porous support and the film, the control of adhesion between the porous support and the film and the provision of excellent running property of the film during lamination serve as very important factors.

Accordingly, an object of the present invention is to improve the problems as pointed out above, to improve the problem of sticking to the xenon flash lamp or the thermal head (adhesive) and to control the adhesion and running characteristics between the porous support and the film excellent conveying The aim is to provide a highly functional thermal stencil printing base that can be printed with high sensitivity and high thermal sensitivities with high print durability.

In the thermal stencil printing base according to the present invention for solving the above problems, the thermal stencil printing base is made of a film and a porous support, the film is a two-layer coextrusion biaxial stretching consisting of a surface layer (A) and an inner layer (B) A film is used to achieve a thickness ratio of the surface layer A to the total film layer in a ratio of 0.01 to 0.1, and the difference between the glass transition temperatures of the surface layer A and the inner layer B is ΔTg ≦ 20 ° C. Can be.

If the thickness of the surface layer (A) is too thick in the above, the energy required for drilling is increased to decrease the printing sensitivity, and the thickness is preferably about 1% to 10% of the total thickness. In addition, by using a resin having a glass transition temperature of the surface layer (A) higher than the glass transition temperature of the inner layer (B), it is possible to obtain clear print quality by preventing wrinkles of the film due to puncture energy.

When the difference between the glass transition temperatures of the films constituting the surface layer (A) and the inner layer (B) is 20 ° C. or more, due to the shrinkage of the film, due to the difference in shrinkage between the surface layer (A) and the inner layer (B) This warping phenomenon, that is, curl occurs, and the deformation of the paper is caused by the heat supplied from the heat head at the time of punching and printing, and the curl generated by the heat deteriorates the conveyability, the deformation of the paper and This can cause damage and deterioration of print quality.

In addition, even when the biaxially stretched film is produced, the stretchability of the film is poor, and there is a problem in that it is impossible to produce a good quality film due to the thickness variation of the film or the widthwise property variation of the film due to the nonuniform stretching.

At this time, in the two-layer coextrusion biaxially oriented film used as the thermal plate printing paper, the total thickness of the film is suitably 0.5 µm to 4 µm.

As the resin that can be used to prepare the two-layer coextruded biaxially stretched film, polyamide, polyethylene, polypropylene, soft polyolefin, polyvinylidene chloride, polyvinyl chloride, and polyester resins as described above may be used. Among the films made of such resins, polyester films having excellent oil resistance, temperature stability, and Young's modulus are most preferred for thermal stencil printing paper.

The term "polyester" referred to in the present invention means a polyester containing an aromatic dicarboxylic acid as the main acid component and an alkylene glycol as the main glycol component. Examples of the aromatic dicarboxylic acid are terephthalic acid, isophthalic acid and naphthalene. Dicarboxylic acid, diphenoxy ethane dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid and diphenyl ketone dicarboxylic acid, among which terephthalic acid desirable.

Examples of the alkylene glycol of the glycol component include ethylene glycol, 1,4-butanediol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, and hexamethylene glycol, of which ethylene glycol is most preferred.

In addition, the polyester may also be used in the copolymer state, and as copolymerizable components, diethylene glycol, propylene glycol, neopentin glycol, polyalkylene glycol, para-xylene glycol, 1,4-cyclohexanedi Glycol components such as methanol and 5-sodium sulforezocin; Dicarboxylic acid components such as adipic acid, sebacic acid, phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid and 5-sodium isophthalic acid; Multifunctional dicarboxylic acid components such as trimellitic acid and pyromellitic acid; In addition, an oxycarboxylic acid component such as para-oxyethoxybenzoic acid may be used, and the content of such copolymerizable components is preferably contained within the range of 2 to 25 mol% based on the total polyester resin component. More preferably, 20 mol% is contained.

Moreover, it is also possible to add well-known additives for polyester films, such as an antistatic agent and a heat stabilizer, in quantity in the range in which the basic characteristic of a film does not fall to polyester.

The film used for the two-layer coextrusion biaxially stretched thermosensitive plate printing paper using the resin as described above is characterized in that the resin constituting the surface layer (A) and the inner layer (B) has a surface temperature (A) of melting temperature (Tma). Is a resin having a temperature of 230 ° C. to 280 ° C. and a melting energy (ΔHua) of 11 to 18 cal / g, and the inner layer B has a melting temperature (Tmb) of 170 ° C. to 220 ° C. and a melting energy (ΔHub). ) Is preferably composed of a resin having 3 to 10 cal / g.

The reason why the melting temperature (Tma) of the surface layer (A) should be about 230 ° C. to 280 ° C. is that when the melting temperature is higher than 280 ° C., it is difficult to perforate with the heat energy generated from the xenon flash lamp or the thermal head. In addition to the need for a large amount of thermal energy, it is also difficult to control the desired drilling diameter, making it impossible to print in high resolution. When the melting temperature (Tma) is about 230 ° C. or lower, the anti-sticking effect is lowered. It adheres to the thermal head and also greatly reduces the print quality.

The reason why the melting temperature of the inner layer (B) as the main puncture layer should be about 170 ° C. to 220 ° C. is that when the melting temperature of the inner layer (B) as the main puncture layer becomes 170 ° C. or less, the puncture diameter becomes excessively large. There is also a problem that the printing durability falls, when the melting temperature is higher than 220 ℃ heat energy required for drilling is large, print sensitivity is low.

The surface roughness of the surface layer A and the inner layer B was 0.05 µm to 0.1 µm for the surface roughness Ra of the surface layer A, and the surface roughness Ra of the inner layer B was 0.01 µm to 0.05 µm. It is desirable to give.

The reason why the surface roughness (Ra) of the surface layer (A) used as the anti-sticking layer should be about 0.01 μm to 0.05 μm is high speed without lamination or wrinkle insertion of the film when laminating the porous support and the film. To be able to stably laminate, the surface roughness (Ra) of the inner layer (B), which is the main perforated layer laminated with a porous support and laminated with an adhesive, should be about 0.05 μm to 0.1 μm to improve adhesion even under the same bonding conditions. Since it is possible to improve the printing durability of the thermal stencil printing paper, and to minimize the occurrence of curl on the thermal stencil printing paper, high speed printing and printing quality can be improved.

The thermal stencil printing base consisting of the film for the thermal stencil printing base and the porous support of the present invention having the above configuration is easily perforated by heat generated from a xenon flash lamp or a thermal head, but is also a thermal head. It does not stick to the back, and the puncturing density is good, it enables clear printing, high-speed printing, printing durability is greatly improved, and the print quality has high sensitivity to heat. -Print symbols or symbols are clearly displayed and the thickness is constant, so that the shade of printed images becomes constant, and it is possible to laminate at high speed even when manufacturing heat-sensitive plate printing paper. It has the advantage that it is easy to handle.

The two-layer coextruded polyester biaxially oriented film according to the present invention may be prepared by the following method using a conventionally known coextrusion method.

First, homogeneous or heterogeneous polyester is selected from the above-mentioned resins, and coextruded each resin to prepare a two-layered amorphous sheet, followed by biaxial stretching through longitudinal stretching and transverse stretching. It is prepared by the application.

For example, a continuous sheet can be produced by supplying molten resin to a multi-manifold die or feed block die and fixing the plate-like molten resin to a rotating cooling drum, which is then stretched in the longitudinal direction. To undergo a longitudinal stretching process, either one-stage or multistage stretching methods may be used, and after the longitudinal stretching process, the film is biaxially stretched by stretching in the transverse direction and then heat-treated.

The film produced by the method as described above is to be laminated on the surface of the porous support via the adhesive or without the adhesive to prepare a thermal stencil printing base.

Here, the two-layer coextrusion biaxially oriented film is divided into a surface layer (A) and an inner layer (B), and each layer plays the following role. Here, the surface layer (A) acts as a stick prevention layer and the inner layer (B) acts as a main perforated layer. First, the surface layer (A) as the anti-stick layer is a thermally sensitive plate at the time of perforation by thermal energy. It prevents the film surface of the printing paper from sticking to the heat head during engraving by the heat head, or prevents the film surface from sticking to the components of the thermal plate printer during transportation, and wears the perforated printing disc during high speed mass printing. It prevents contamination and print quality from dropping out.

The inner layer B, which is the main perforated layer, is a layer that is perforated by actual heat, and thus perforation can be performed at high speed even at low thermal energy.

Hereinafter, the effects of the present invention will be described in detail with reference to the following examples, but the present invention is not limited only to the following examples.

Example 1

Polyester resin A using dimethyl terephthalate as acid component, ethylene glycol as glycol component, 80 mol% of dimethyl terephthalate and 20 mol% dimethyl isophthalate as acid component, and copolymerized with ethylene glycol as glycol component Resin B was supplied to each of two extruders and melt-extruded at about 290 ° C to discharge T-Die, which is capable of forming a laminated sheet, and then cooled and solidified in a casting drum having a surface temperature of about 35 ° C by an electrostatic casting method. To give an unstretched film of 2.5%. Here, the polyester resin A is a layer A which is an anti-sticking layer, and another polyester resin B is melt-extruded so that it is the B layer which is the main perforation side, and an unstretched film is manufactured. The unstretched film obtained in this manner is stretched at least about 3.5 times in the longitudinal direction and then stretched at least about 3.8 times in the transverse direction. The biaxially stretched film thus obtained was heat-treated at a relaxation rate of 2% to prepare a two-layer coextruded polyester biaxially stretched film having a thickness of 1.5 µm, and the two-layer coextruded polyester biaxially stretched film was laminated to a porous support to heat-sensitive plate printing. Prepare the base paper.

<Example 2>

Polyester resin A is prepared using 2,6-dimethylnaphthalate as the acid component and ethylene glycol as the glycol component, and polyester resin B is prepared using the same components as in Example 1. Two resins thus prepared were prepared in the same manner as described in Example 1 to prepare a two-layer coextruded polyester biaxially stretched film having a thickness of 1.5 μm, and the two-layer coextruded polyester biaxially stretched film was placed on a porous support. Lamination to prepare a thermal stencil printing paper.

<Comparative Examples 1-3>

Polyester resin B was prepared using the same components as in Example 1, and Comparative Examples 1 to 3 each used polyester resin A as an acid component, and 90 mol%, 85 mol%, 80 mol%, and dimethyl isophthalate were used. It is prepared by using 10mol%, 15mol%, 20mol% and using ethylene glycol as the glycol component. The two resins thus prepared were prepared in the same manner as in Example 1 to prepare a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm, and the two-layer coextruded polyester biaxially oriented film was laminated to a porous support to heat-sensitive plate. Prepare printing paper.

<Comparative Example 4>

Polyester resin A is prepared by copolymerizing 80 mol% of dimethyl terephthalate and 20 mol% of dimethylisophthalate as the acid component and ethylene glycol as the glycol component. Polyester resin B is prepared using dimethyl terephthalate as an acid component and ethylene glycol as a glycol component. Using these two resins, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was laminated to the porous support. To prepare a thermal plate printing paper.

<Examples 3-4, Comparative Examples 5-6>

Polyester resins A and B use the same polyester resins as mentioned in Example 1, and these two polyester resins are supplied to two extruders, respectively, and melt-extruded at about 290 ° C., thereby enabling the formation of a laminated sheet. After discharging the T-Die, the sheet is formed by laminating by cooling by a casting drum having a surface temperature of about 35 ° C. by electrostatic applied casting method. Examples 3-4 and Comparative Examples 5-6 use the unstretched film which becomes 5%, 10%, 15%, and 20% of the layer composition ratio of a sheet, respectively. The unstretched film thus obtained is stretched at least about 3.5 times in the longitudinal direction and then stretched at least about 3.8 times in the transverse direction. The biaxially stretched film was heat-treated at a relaxation rate of 2% to prepare a two-layer coextruded polyester biaxially stretched film having a thickness of 1.5 µm, and the two-layer coextruded polyester biaxially stretched film was laminated to a porous support to heat-sensitive plate printing paper. Manufacture.

<Examples 5-8, Comparative Examples 7-8>

The same polyester resin A as mentioned in Example 1 was used, and 95 mol%, 90 mol%, 85 mol%, 80 mol%, 75 mol%, 70 mol% of dimethyl terephthalate as the acid component of polyester resin B and 5 mol of dimethyl isophthalate were used. %, 10 mol%, 15 mol%, 20 mol% and 25 mol%, respectively, were prepared by copolymerizing with ethylene glycol which is a glycol component, and used as the polyester resins B of Examples 5 to 8 and Comparative Examples 7 to 8, respectively. Using the resin thus prepared, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was prepared on the porous support. Lamination to prepare a thermal stencil printing paper.

Example 9

Dimethyl terephthalate is used as an acid component, ethylene glycol is used as a glycol component, and 0.7 wt% of SiO2, which is an inert inorganic particle having an average particle diameter (D50) of 1.6 µm, is added to polyester resin A. Polyester resin B uses 80 mol% of dimethyl terephthalate and 20 mol% of dimethyl isophthalate as the acid component, ethylene glycol as the glycol component, and 0.5 wt% of CaCO3, an inert inorganic particle having an average particle diameter (D50) of 0.8 μm. By copolymerization. Using the resin thus prepared, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was prepared on the porous support. Lamination to prepare a thermal stencil printing paper.

<Example 10>

Dimethyl terephthalate is used as an acid component, ethylene glycol is used as a glycol component, and 0.5 wt% of SiO2, which is an inert inorganic particle having an average particle diameter (D50) of 1.6 µm, is added to the polyester resin A. Polyester resin B uses 80 mol% of dimethyl terephthalate and 20 mol% of dimethyl isophthalate as the acid component, ethylene glycol as the glycol component, and 0.5 wt% of CaCO3, an inert inorganic particle having an average particle diameter (D50) of 0.8 μm. By copolymerization. Using the resin thus prepared, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was prepared on the porous support. Lamination to prepare a thermal stencil printing paper.

<Example 11>

Dimethyl terephthalate is used as an acid component, ethylene glycol is used as a glycol component, and 0.5 wt% of SiO 2, which is an inert inorganic particle having an average particle diameter (D50) of 1.0 μm, is added to polyester resin A. Polyester resin B uses 80 mol% of dimethyl terephthalate and 20 mol% of dimethyl isophthalate as the acid component, ethylene glycol as the glycol component, and 0.5 wt% of CaCO3, an inert inorganic particle having an average particle diameter (D50) of 0.8 μm. By copolymerization. Using the resin thus prepared, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was prepared on the porous support. Lamination to prepare a thermal stencil printing paper.

Comparative Example 9

Dimethyl terephthalate is used as an acid component, ethylene glycol is used as a glycol component, and 0.5 wt% of CaCO3, an inert inorganic particle having an average particle diameter (D50) of 0.8 µm, is added to polyester resin A. Polyester resin B uses 80 mol% of dimethyl terephthalate and 20 mol% of dimethyl isophthalate as the acid component, ethylene glycol as the glycol component, and 0.5 wt% of CaCO3, an inert inorganic particle having an average particle diameter (D50) of 0.8 μm. By copolymerization. Using the resin thus prepared, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was prepared on the porous support. Lamination to prepare a thermal stencil printing paper.

Comparative Example 10

Dimethyl terephthalate is used as an acid component, ethylene glycol is used as a glycol component, and 0.5 wt% of CaCO3, an inert inorganic particle having an average particle diameter (D50) of 0.8 µm, is added to polyester resin A. Polyester resin B uses 80 mol% of dimethyl terephthalate and 20 mol% of dimethylisophthalate as acid component, ethylene glycol as glycol component, and 0.5 wt% of SiO2, an inert inorganic particle having an average particle diameter (D50) of 1.6 μm. By copolymerization. Using the resin thus prepared, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was prepared on the porous support. Lamination to prepare a thermal stencil printing paper.

Comparative Example 11

Dimethyl terephthalate is used as an acid component, ethylene glycol is used as a glycol component, and 0.7 wt% of SiO2, which is an inert inorganic particle having an average particle diameter (D50) of 1.6 µm, is added to polyester resin A.

Polyester resin B uses 80 mol% of dimethyl terephthalate and 20 mol% of dimethyl isophthalate as the acid component, ethylene glycol as the glycol component, and 0.7 wt% of SiO2, an inert inorganic particle having an average particle diameter (D50) of 1.6 μm, is added. By copolymerization. Using the resin thus prepared, a two-layer coextruded polyester biaxially oriented film having a thickness of 1.5 μm was prepared by the same method as described in Example 1, and the two-layer coextruded polyester biaxially oriented film was prepared on the porous support. Lamination to prepare a thermal stencil printing paper.

The films prepared according to Examples 1 to 11 and Comparative Examples 1 to 11 were tested by the following test methods, and the results are shown in Tables 1 and 2.

[Measurement method of characteristics and evaluation method of effects]

(1) melting energy, melting temperature, glass transition temperature

Ⓐ melt energy

Differential scanning calorimeter DSC (available from Perkin-Elmer Co., Ltd.) is used to determine the crystal melting energy from the area (α) of the area in the thermogram of the film for thermal stencil printing during melting. The temperature increase rate at the time of a measurement is made into about 20 degree-C / min, and it measures by making a measurement sample volume into 10 mg. The area representing the crystal melting energy is an area located between the baseline of thermogram and the differential thermal curve in the range from the melting start temperature to the melting end temperature. In other words, while the heating continues, the parallax heat curve deviates from the baseline to the endothermic side and then returns to the baseline. The area α is the area of the region between the parallax heat curve deviating from the baseline and the straight line connected to the point where the lag curve starts to deviate and returns to the baseline. In the same way, the area? Is measured for the indium in the same manner as above, and the melt energy is obtained by the following equation using the area? And the area?.

α / β × 6.8 = ΔHu (cal / g)

Ⓑ melting temperature

Measured in the same way as in section ⓐ above to obtain a Thermogram, where the parallax thermal curve decreases from increasing in the interval where the parallax thermal curve on the Theogram is out of the baseline and back to the baseline. The temperature at the point of conversion to is measured as the melting temperature (Tm).

Ⓒ glass transition temperature

Using a differential scanning calorimetry DSC as used in section ⓐ above, take 10 mg of the sample, hold at 280 ° C for about 5 minutes, and quench with liquid nitrogen. The glass transition temperature (Tg) is measured by a conventional method from the differential heating wire on the thermogram measured while raising the sample subjected to this pretreatment at a heating rate of 20 ° C./min.

(2) Floor composition ratio

The cross-section is cut out by a microtome for a co-extruded sheet or a co-extruded polyester biaxially stretched film, and the cut-out cross section is measured with an electron microscope photograph of 100,000 times, and it calculates by the following formula.

Layer composition ratio (%) = A layer thickness / (A layer thickness + B layer thickness) x 100

(3) Surface roughness (Ra)

It is measured using a contact surface roughness measuring instrument according to JIS B 061, and the cut-off value is set to 0.25 mm.

(4) Evaluation of adhesion resistance (sticking resistance)

In the heat-sensitive plate printing paper made by laminating the film and the porous support, the surface of the anti-stick layer is brought into contact with the thermal head, and the degree of sticking is determined based on the following criteria when perforating by thermal energy. ] Sticking resistance was good when the above evaluation was received.

(Double-circle): No adhesion generate | occur | produces at all, normal perforation is possible, and running property is very favorable.

(Circle): There is no problem in driving property and normal perforation is possible, but some stick generate | occur | produces in a beta printing part.

(Triangle | delta): It runs but normal drilling is impossible.

X: It does not run at all.

(5) Print durability evaluation

The number of printable sheets is displayed as the number of printable sheets until the film for thermal plate printing paper is damaged in the Lithographic GR 2750 plate making press (manufactured by Sang-Suk Science Co., Ltd.).

(6) Evaluation of Character Printing

Thermal plate printing is carried out using a document of character size 2.0 mm long. Manuscripts and heat-printed manuscripts attached to the Lithographic GR 2750 Engraving Press (manufactured by Sang-Soo Scientific Co., Ltd.) were plated and printed. Ⓐ Evaluation of the absence of letters and ⓑ Evaluation of the thickness and blotches of the letters It was. In ⓐ and ⓑ above, there is no problem [○]. [×] which was clearly unusable was indicated.

(7) Better Printing

Printing is carried out in the same manner as mentioned in the above (6), but the paper is printed on the plate-making press using a manuscript of 1 to 5 mm in diameter (with a black circle in the center). Evaluate the printed circle. Evaluate the edges of the printed circle.The thermal stencil printing base, which has a border line with protrusions or depressions of 200㎛ or more than the size of the original, appears on the circle with a bad appearance and is not printed clearly. This is represented by ×. In addition, it is evaluated that it is clear that the protrusion part or the depression part of 50 micrometers or less size is formed, and it is represented by (circle). In the case of 50 μm to 200 μm, which do not correspond to the above two cases, it is expressed as △ and is evaluated as being usable.

(8) evaluation of sensitivity

A pencil with hardness of 5H, 4H, 3H, 2H, and H is used to write the text to be printed while pressing with a force of 150g. The printing is carried out in the same manner as mentioned in the above (6) to determine whether the printed character is read. Characters written in pencil with a hardness of 5H are the most faint and characters written in pencil with a hardness of H are the darkest, so if a printed character written in pencil with a 5H is readable, the sensitivity is the best. The sensitivity of the pencil, from which the readable characters can be made, goes from 5H to H. Sensitivity is evaluated as the hardness of a pencil on which printable characters can be made.

(9) dysplasia

After engraving, the degree of manuscript dropping from the thermal stencil is evaluated. If the manuscript falls without any resistance, it is evaluated as having excellent releasability. In addition, not only defects remain in the plate making area when the original is removed, but also the damage to the film for thermal stencil printing paper is evaluated as unusable and indicated by x.

(10) high speed printing

The printed matter after printing 5000 sheets at a printing speed of 60 sheets / minute, 80 sheets / minute, 100 sheets / minute, 120 sheets / minute, and 130 sheets / minute by using the thermal stencil printing machine mentioned in (5) above. Compare the quality with the manuscript. High-speed printing is evaluated at the maximum printing speed at which the original and print quality are the same.

(11) Curl

One sheet of thermal stencil printing paper is cut into 200 mm x 200 mm to make a square sample. Place the cut sample on the plate and measure the distance (height) of each corner of the square, plate and distance (height). On the basis of having the largest value of the distance between the edges and the flat plate, it shall be regarded as excellent in case of 10mm or less, and marked by ○, and in case of 10mm or more by bad and marked by x.

(12) Runability

When preparing the thermal stencil printing paper, that is, laminating the porous support and the film, the degree of shaking of the film is visually evaluated. When shaking does not occur at all during lamination, it is evaluated as having excellent driving performance, and is marked as ○, and when film shaking occurs, it is evaluated as having poor driving performance and is indicated by ×.

division Melt Energy (cal / g) [A / B] Melt Temperature (℃) [A / B] Glass Transition Temperature (℃) [A / B] Layer Composition Ratio (%) [A / (A + B] × 100 Adhesion Resistance Print durability (sheets) Character printing Better printing Sensitivity Dysplasia Example 1 15/5 257/202 81/72 2.5 ◎ 30,000 ○ ○ 5H ○ Example 2 17/5 266/202 125/72 2.5 ◎ 30,000 ○ ○ 5H ○ Comparative Example 1 10/5 229/202 73/72 2.5 △ 20,000 ○ ○ 5H ○ Comparative Example 2 7/5 213/202 73/72 2.5 △ 20,000 ○ ○ 5H ○ Comparative Example 3 5/5 202/202 73/72 2.5 × 10,000 ○ ○ 4H × Comparative Example 4 5/15 202/257 72/81 2.5 × 5,000 × × 1H × Example 3 15/5 257/202 81/72 5 ◎ 30,000 ○ ○ 5H ○ Example 4 15/5 257/202 81/72 10 ◎ 20,000 ○ ○ 5H ○ Comparative Example 5 15/5 257/202 81/72 15 ◎ 30,000 △ △ 2H × Comparative Example 6 15/5 257/202 81/72 20 ◎ 30,000 × × 1H × Example 5 15/11 257/245 81/77 2.5 ◎ 30,000 × × 1H ○ Example 6 15/10 257/229 81/76 2.5 ◎ 30,000 △ △ 4H ○ Example 7 15/7 257/213 81/73 2.5 ◎ 20,000 ○ ○ 5H ○ Example 8 15/5 257/202 81/72 2.5 ◎ 20,000 ○ ○ 5H ○ Comparative Example 7 15/3 257/190 81/71 2.5 ◎ 10,000 ○ ○ 4H ○ Comparative Example 8 15/1 257/181 81/70 2.5 ◎ 5,000 ○ ○ 3H ○

division Surface Roughness Ra (㎛) [A / B] High Speed Printing (sheets / minute) Print durability (sheets) Curl Run Example 9 0.09 / 0.03 130 30,000 ○ ○ Example 10 0.07 / 0.03 130 30,000 ○ ○ Example 11 0.05.0.03 130 30,000 ○ ○ Comparative Example 9 0.03 / 0.03 100 10,000 ○ × Comparative Example 10 0.03 / 0.07 100 10,000 × × Comparative Example 11 0.09 / 0.09 130 30,000 × ×

As described above, the present invention improves adhesion to xenon flash lamps or thermal heads and adjusts adhesion and running characteristics between the porous support and the film, thereby providing excellent conveyability and high printing durability, but also having high print quality. It is a useful invention to provide a high functional thermal stencil printing base capable of high sensitivity thermal stencil printing.

Claims (24)

In a thermal stencil printing base composed of a synthetic resin film and a porous support, a film is used as a two-layer coextrusion biaxially oriented film composed of a surface layer (A) and an inner layer (B), and is used for the total film layer The thickness of the surface layer (A) is a ratio of 0.01 to 0.1, the difference between the glass transition temperature of the surface layer (A) and the inner layer (B) is ΔTg≤20 ℃ characterized in that the thermal plate printing paper. The heat-sensitive plate printing paper according to claim 1, wherein the resin constituting the two-layer coextrusion biaxially oriented film is a polyester resin. The thermal stencil printing base according to claim 2, wherein the polyester resin contains a resin produced by the reaction of aromatic dicarboxylic acid and alkylene glycol as a main component. The method according to claim 3, wherein the polyester resin is in a copolymer state, and as copolymerizable components, diethylene glycol, propylene glycol, neopentin glycol, polyalkylene glycol, para-xylene glycol, 1,4-cyclohexanedi Glycol components such as methanol and 5-sodium sulforezocin; Dicarboxylic acid components such as adipic acid, sebacic acid, phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid and 5-sodium isophthalic acid; Multifunctional dicarboxylic acid components such as trimellitic acid and pyromellitic acid; And a component selected from oxycarboxylic acids such as para-oxyethoxybenzoic acid within the range of 2 to 25 mol% with respect to the entire polyester resin component. The thermal stencil printing base according to claim 4, wherein the copolymer component is contained in an amount of 5 to 20 mol% based on the entire polyester resin. The thermosensitive plate printing base according to any one of claims 1 to 5, wherein the thickness of the two-layer coextrusion biaxially stretched film is 0.5 µm to 4 µm. The inner and outer surface roughness of the two-layer coextruded polyester biaxially stretched film is a film having a surface layer (A) of 0.05 µm to 0.1 µm and an inner layer (B) of 0.01 µm to 0.05 µm. Thermal stencil printing base. The inner and outer surface roughness of the two-layer coextruded polyester biaxially oriented film is a film having a surface layer (A) of 0.05 µm to 0.1 µm and an inner layer (B) of 0.01 µm to 0.05 µm. Thermal stencil printing base, characterized in that. The resin composition of the surface layer and the inner layer is characterized in that the surface layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. And the inner layer is made of a resin having a melting temperature (Tmb) of 170 ° C to 220 ° C and a melting energy (ΔHub) of 3 to 10 cal / g. The resin layer constituting the surface layer and the inner layer is characterized in that the surface layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. A heat-sensitive plate printing paper, characterized in that the layer is composed of a resin having a melting temperature (Tmb) of 170 ° C to 220 ° C and a melting energy (ΔHub) of 3 to 10 cal / g. The resin layer constituting the surface layer and the inner layer is characterized in that the surface layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. A heat-sensitive plate printing paper, characterized in that the layer is composed of a resin having a melting temperature (Tmb) of 170 ° C to 220 ° C and a melting energy (ΔHub) of 3 to 10 cal / g. The resin composition of the surface layer and the inner layer is characterized in that the surface layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. A heat-sensitive plate printing paper, characterized in that the layer is composed of a resin having a melting temperature (Tmb) of 170 ° C to 220 ° C and a melting energy (ΔHub) of 3 to 10 cal / g. In the method for producing a thermal stencil printing paper by laminating a synthetic resin film on a porous support, the difference between the glass transition temperature of the surface layer (A) and the inner layer (B) of the same or different resins is ΔTg ≦ 20 The resin was co-extruded so that the composition ratio of the surface layer (A) and the total film layer was in the ratio of 0.01 to 0.1 to prepare a two-layered amorphous sheet, followed by longitudinal stretching and transverse stretching. Biaxial stretching to prepare a two-layer coextruded biaxially oriented film consisting of the surface layer (A) and the inner layer (B), and thermally plated printing, characterized in that to laminate the prepared two-layer coextruded biaxially oriented film on a porous support Method of making base paper. The method for producing a thermosensitive plate printing paper according to claim 13, wherein the resin constituting the two-layer coextrusion biaxially stretched film is a polyester resin. The method according to claim 14, wherein the polyester resin contains a resin produced by the reaction of aromatic dicarboxylic acid and alkylene glycol as a main component. The method of claim 15, wherein the polyester resin is in a copolymer state, and as copolymerizable components, diethylene glycol, propylene glycol, neopentin glycol, polyalkylene glycol, para-xylene glycol, 1,4-cyclohexanedi Glycol components such as methanol and 5-sodium sulforezocin; Dicarboxylic acid components such as adipic acid, sebacic acid, phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid and 5-sodium isophthalic acid; Multifunctional dicarboxylic acid components such as trimellitic acid and pyromellitic acid; And a component selected from oxycarboxylic acids such as para-oxyethoxybenzoic acid in the range of 2 to 25 mol% with respect to the entire polyester resin component. The method for producing a thermal stencil printing base material according to claim 16, wherein the copolymer component is contained in an amount of 5 to 20 mol% based on the entire polyester resin. The thickness of the two-layer coextrusion biaxially stretched film is 0.5 micrometer-4 micrometers, The manufacturing method of the thermographic printing sheet of any one of Claims 13-17 characterized by the above-mentioned. 19. The film according to claim 18, wherein the inner and outer surface roughness of the two-layer coextruded polyester biaxially stretched film is a surface layer (A) of 0.05 µm to 0.1 µm and an inner layer (B) of 0.01 µm to 0.05 µm. Method of producing a thermal stencil printing paper. The surface roughness of the inner and outer surfaces of the two-layer coextruded polyester biaxially oriented film is a surface layer (A) of 0.05 µm to 0.1 µm and the inner layer (B) of 0.01 µm to 0.05 µm. Method for producing a thermal stencil printing paper, characterized in that. 18. The resin according to any one of claims 13 to 17, wherein the resin constituting the surface layer and the inner layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. And the inner layer is made of a resin having a melting temperature (Tmb) of 170 ° C to 220 ° C and a melting energy (ΔHub) of 3 to 10 cal / g. 19. The characteristics of the resin constituting the surface layer and the inner layer is that the surface layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. The layer is made of a resin of thermal plate printing paper, characterized in that the melting temperature (Tmb) is 170 ° C to 220 ° C and the melting energy (ΔHub) is 3 to 10 cal / g. The resin composition of the surface layer and the inner layer according to claim 19, wherein the surface layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. The layer is made of a resin of thermal plate printing paper, characterized in that the melting temperature (Tmb) is 170 ° C to 220 ° C and the melting energy (ΔHub) is 3 to 10 cal / g. The resin according to claim 20, wherein the resin constituting the surface layer and the inner layer is a resin having a melting temperature (Tma) of 230 ° C to 280 ° C and a melting energy (ΔHua) of 11 to 18 cal / g. The layer is made of a resin of thermal plate printing paper, characterized in that the melting temperature (Tmb) is 170 ° C to 220 ° C and the melting energy (ΔHub) is 3 to 10 cal / g.