JP3465375B2 - Film for heat-sensitive stencil printing base paper - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to relates to a full I <br/> Lum for stencil printing sheet. For more information relates stencil printing sheet for full Irumu being perforated plate-making by heat, more particularly drilling characteristics receives heat by xenon flash lamp or a thermal head or the like (perforation sensitivity, independence perforated), print sharpness (character printing, to a heat-sensitive stencil printing sheet for full Irumu having excellent solid printing).

[0002]

2. Description of the Related Art Conventionally, as a heat-sensitive stencil printing base paper, a heat-sensitive stencil printing base paper film laminated on a porous support (Japanese paper) by heat or an adhesive is known.
Films of various resins such as vinyl chloride / vinylidene chloride copolymer, polypropylene and polyester have been used as the film for heat-sensitive stencil printing base paper.

However, the current heat-sensitive stencil printing base paper is liable to cause printing unevenness during solid printing, has large thickness unevenness and poor flatness, is poor in aptitude for lamination with a porous support, and is apt to cause printing unevenness, and has a dark and light print portion. No clear image can be obtained, the thickness of characters is partially uneven, thin black characters do not appear and gradation is poor, and perforation sensitivity is improved by the adhesive used to adhere to the porous support. However, there were drawbacks such as differences in resolution.

In general, when a plastic film is used as a film for heat-sensitive stencil printing paper, a stick phenomenon occurs in which a part of the film is fused to the thermal head by the heat given by the thermal head. If this phenomenon occurs, not only the film will not run smoothly, but also the thermal head will be significantly contaminated, and the printing sharpness will be impaired. In addition, there is a problem that fusion with the document occurs when punching with a flash lamp.

Further, the current heat-sensitive stencil printing base paper is perforated by a head having a high heat applied energy for practical use, and has a drawback that the life of the head is shortened due to high heat application. Further, when used in a commercially available facsimile machine, word processor, etc., since this model is a head with low heat application energy, there is a drawback that the perforation sensitivity is poor and the target independent perforation cannot be obtained, so that the printing sharpness is reduced.

Further, since the biaxially stretched polyester film is an insulator, it is significantly charged by static electricity, which may cause wrinkles or the like in post-processing or dust or the like to cause perforation failure. Since the surface of the axially stretched polyester film is highly oriented, it has a drawback that the adhesiveness of the adhesive and the porous support is poor.

Many proposals have been made to solve the problems involved. For example, JP-A-2-15839 discloses a film having excellent perforation properties in the low heat application energy region.
No. 1 and JP-A-4-173835, a film having polybutylene terephthalate as a main component and having a low melting point and high crystallinity, JP-A-62-282983, and JP-A-4-282983.
No. 224925 and Japanese Unexamined Patent Publication No. 5-77572, a film that defines the thermal properties and thermal shrinkage properties of a polymer obtained by copolymerizing 1,4-cyclohexanedimethanol and isophthalic acid and Japanese Unexamined Patent Publication No. 2-113995, Kaihei 3
No. 39294 discloses a blending system of thermoplastic resins such as polyethylene terephthalate and polybutylene terephthalate, and polyethylene terephthalate having an average molecular weight of 200.
A film or the like has been proposed in which 30% by weight of polyethylene glycol of 00 is blended to define thermal characteristics.

[0008]

However, the above-mentioned drawbacks have not been solved in the prior art, and the perforation sensitivity and the perforation characteristics of independent perforation are poor in the low heat application energy region, and the heat storage energy after perforation is caused. There are drawbacks such as the molten polyester flowing and expanding the perforation diameter, blocking and sticking to reduce the printing clarity of character printing and solid printing.

An object of the present invention, brought overcome these drawbacks and to provide a low perforation characteristics in thermal energy applied area, printing stencil printing sheet for full Irumu excellent in vividness.

[0010]

The above-mentioned objects of the present invention are as follows: aromatic dicarboxylic acid, aliphatic dicarboxylic acid and / or
Alternatively, from at least one or more acid components selected from alicyclic dicarboxylic acids and at least one or more glycol components selected from aliphatic glycols having 2 to 10 carbon atoms and / or alicyclic glycols having 6 to 16 carbon atoms. And a number average molecular weight of 6000 to 110
Thousands of poly ethylene glycol component can <br/> Thus achieved in the thermal stencil sheet film made of heat-sensitive stencil sheet for polyester composition characterized by containing less than 20 wt%.

The polyester composition in the present invention is
At least one or more acid components selected from aromatic dicarboxylic acids, aliphatic dicarboxylic acids and / or alicyclic dicarboxylic acids, and aliphatic glycols having 2 to 10 carbon atoms and / or
Alternatively, a polyester and a polyoxyalkylene glycol component composed of at least one glycol component selected from alicyclic glycols having 6 to 16 carbon atoms and a polyoxyalkylene glycol component of 0.
It is a polyester composition as a constituent component containing from 0 to less than 30% by weight.

Examples of the aromatic dicarboxylic acid component include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, phthalic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid and the like, ester-forming derivatives thereof, 5-sodium sulfoisophthalic acid and the like. Examples thereof include ester-forming sulfonic acid alkali metal salt compounds, and examples of the aliphatic dicarboxylic acid component include oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, fumaric acid and the like, or esters thereof. Examples of the alicyclic dicarboxylic acid component include 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and the like.
Examples thereof include 1,4-cyclohexanedicarboxylic acid, decalin dicarboxylic acid and the like, or ester-forming derivatives thereof. Among them, terephthalic acid, isophthalic acid, 2,
6-naphthalenedicarboxylic acid is preferred. More preferred are terephthalic acid and isophthalic acid. These acid components may be used alone or in combination of two or more.

As the aliphatic glycol component having 2 to 10 carbon atoms, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-
Butanediol, 1,5-pentanediol, 1,6-
Hexanediol, 1,7-heptanediol, 1,8
-Octanediol, 1,9-nonanediol, 1,1
Examples thereof include 0-decanediol and neopentyl glycol. Examples of the alicyclic glycol component having 6 to 16 carbon atoms include 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol and 1,4- Cyclohexanedimethanol, 1,4-cyclohexanediol, 1,3-cyclohexanediol, 1,2-cyclohexanediol, hydrogenated bisphenol A, 3,
9-bis (1,1-bismethyl-2-oxyethyl)-
2,4,8,10-tetraoxaspiro (5,5) undecane and the like can be mentioned. Among them, the drilling characteristics,
From the viewpoint of printing clarity, the glycol component is preferably ethylene glycol or 1,4-cyclohexanedimethanol. More preferably ethylene glycol. These glycol components may be used alone or in combination of two or more.

Examples of polyesters containing these components include polyethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate,
Polycyclohexane dimethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, polybutylene naphthalate, polyhexamethylene naphthalate, polycyclohexane dimethylene naphthalate and the like or copolymerized polyesters thereof can be mentioned.
Of these, polyethylene terephthalate, polyethylene naphthalate, and copolymerized polyesters thereof are preferable.

The polyester of the present invention can be produced by any conventionally known method without any particular limitation. For example, a polyester in which the acid component constituting the polyester is terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid and ethylene glycol as the glycol component and 1,4-cyclohexanedimethanol is preferable, and terephthalic acid as the acid component is 50. ~ 100 mol%, isophthalic acid 0-50 mol%,
Ethylene glycol 100 mol% as glycol component
Polyester consisting of 60 to 95 mol% of terephthalic acid and 5 to 40 of isophthalic acid are particularly preferable as the acid component.
Mol%, ethylene glycol 10 as glycol component
Polyester consisting of 0 mol% is preferred.

The polyester of the present invention may be copolymerized with components other than the acid component and the glycol component constituting the polyester of the present invention, as long as the effects of the present invention are not impaired. Such components include polyfunctional compound components such as trimellitic acid, trimesic acid, pyromellitic acid, tricarballylic acid, trimethylolpropane, glycerin, and pentaerythritol, oxycarboxylic acids such as p-oxybenzoic acid, and phenol. Examples thereof include aromatic glycols having a nucleus, a bisphenol nucleus, a naphthalene nucleus, and the like, and higher fatty acids such as capric acid, lauric acid, stearic acid, and the like.

The polyoxyalkylene glycol component in the present invention is preferably a polyoxyalkylene glycol having a number average molecular weight of 106 to 5,000,000, for example, polymethylene glycol, polyethylene glycol, polytrimethylene glycol, polypropylene glycol, polytetramethylene glycol. And a block or random copolymer of ethylene oxide and propylene oxide. Among them, polyethylene glycol having a number average molecular weight of 1,000 to 2,000,000 is more preferable, and polyethylene glycol having a number average molecular weight of 6,000 to 1,100,000 is more preferable from the viewpoints of perforation characteristics and printing clarity. If the number average molecular weight of the polyoxyalkylene glycol component is less than 106, the perforation properties will be poor and the printing clarity will be poor. On the other hand, when the number average molecular weight exceeds 5,000,000, the compounding property with respect to polyester is poor, the thickness unevenness of the film occurs, the mechanical properties and heat resistance are poor, and the perforation properties and the printing sharpness are deteriorated. A heat-sensitive stencil printing base film suitable for the purpose cannot be achieved. These polyoxyalkylene glycols may be used alone,
You may use together 2 or more types, and also polyoxyalkylene glycol from which a number average molecular weight differs.

The content of the polyoxyalkylene glycol component of the present invention depends on the blendability with polyester, the perforation characteristics,
From the viewpoint of printing clarity, it is 0.
It is necessary that the content is 01 to less than 30% by weight, preferably 0.1 to less than 25% by weight, more preferably 1 to less than 20% by weight. If the content of the polyoxyalkylene glycol component is less than 0.01% by weight with respect to the polyester composition, the perforation properties will be poor and the printing sharpness will be reduced. On the other hand, when the content is 30% by weight or more, the compounding property with respect to polyester is poor, the film has uneven thickness, and the mechanical properties and heat resistance are poor. Further, the glass transition temperature becomes low, the film handling property deteriorates, and further, the quality of the film changes with the lapse of time, which causes a problem that, for example, a laminate with a porous support curls. Further, the perforation characteristics and the printing clarity are deteriorated, and the film for heat-sensitive stencil printing base paper adapted to the object of the present invention cannot be reached.

The melting point of the polyester composition of the present invention is preferably 270 ° C. or lower, more preferably 250 ° C. or lower, and further preferably 240 ° C. or lower from the viewpoints of perforation characteristics and printing clarity in the low heat application energy region. is there. On the other hand, when the melting point exceeds 270 ° C., the perforation property is poor and the printing clarity is deteriorated, so that a film for heat-sensitive stencil printing base paper suitable for the purpose of the present invention may not be achieved. Further, the melting point of the polyester composition is 1 from the viewpoint of perforation characteristics and printing clarity.
The temperature is preferably 00 ° C or higher, more preferably 12
The temperature is 0 ° C or higher, and more preferably 140 ° C or higher. On the other hand, when the melting point is less than 100 ° C., the perforation energy and the heat storage energy after perforation causes the perforation diameter to be expanded or clogged so that the printing sharpness is deteriorated, and a film for heat-sensitive stencil printing base paper suitable for the purpose of the present invention is obtained. It may not be reached.

The glass transition point of the polyester composition of the present invention is preferably 0 ° C. or higher, more preferably 2 ° C.
It is 0 ° C. or higher, and more preferably 30 ° C. or higher. If the glass transition point is lower than 0 ° C., the film may not be easily handled, and the quality of the film may change over time, which may cause a problem such as curling of a laminate with a porous support.

The method of incorporating the polyoxyalkylene glycol component of the present invention into the polyester is not particularly limited. For example, a method of adding the polyoxyalkylene glycol component at any stage of the polyester production process, or the polyester and the poly Examples thereof include a method in which the oxyalkylene glycol component is melt-kneaded using an extruder or the like. At this time, the polyoxyalkylene glycol component can be added by any method such as powder, melting or solution state. The polyoxyalkylene glycol component in the present invention contains a polyoxyalkylene glycol component produced as a by-product during the production of polyester.

As the method for producing the polyester composition of the present invention, any conventionally known method can be adopted and it is not particularly limited. For example, there may be mentioned a method in which an acid component or an ester-forming derivative constituting the polyester of the present invention and a glycol component are subjected to an esterification reaction or a transesterification reaction, and then a polycondensation reaction is carried out at high temperature under reduced pressure. At this time, the polyoxyalkylene glycol component can be added at any stage of the polyester production process to produce the polyester composition of the present invention.

As a specific polyester composition of the present invention, for example, a polyester composition obtained by adding polyethylene glycol as a polyoxyalkylene glycol component to a polyester composed of terephthalic acid and isophthalic acid as acid components and ethylene glycol as a glycol component. The manufacturing method will be described. The first-stage reaction in which the terephthalic acid and isophthalic acid are directly esterified with ethylene glycol or the dimethyl terephthalate and dimethyl isophthalate are transesterified with ethylene glycol, and the reaction product of the first stage is The second step of conducting the condensation reaction is employed, and the addition of polyethylene glycol is carried out from the first step after the completion of the transesterification reaction to the polycondensation reaction at any step before the completion of the polycondensation reaction of the second step. It is preferable to add polyethylene glycol from the first stage after the completion of the transesterification reaction to the second stage before the start of the polycondensation reaction.

At this time, in producing the polyester composition of the present invention, a conventionally known reaction catalyst such as a metal compound,
A coloring inhibitor such as a phosphorus compound can be appropriately used.
Examples of such reaction catalysts include alkali metal compounds, alkaline earth metal compounds, zinc compounds, lead compounds,
Examples thereof include manganese compounds, cobalt compounds, aluminum compounds, germanium compounds, antimony compounds and titanium compounds. Examples of phosphorus compounds include phosphoric acid, phosphorous acid, phosphonic acid, and their derivatives. You may use these 2 or more types together.

The polyester composition of the present invention may optionally contain an antioxidant, an antistatic agent, a weather resistance agent, a terminal blocking agent,
Organic lubricants such as pigments, dyes, fatty acid esters and waxes, or defoaming agents such as polysiloxanes may be added, and clay, mica, titanium oxide, calcium carbonate, kaolin, wet type may be added for the purpose of imparting lubricity. And inorganic particles such as dry process silica, colloidal silica, calcium phosphate, barium sulfate, and alumina, and further organic particles having acrylic acid, styrene, etc. as constituent components may be blended, and two or more of these may be used in combination. Good.

Further, conventionally known thermoplastic resins may be blended within a range that does not impair the effects of the present invention.

The thickness of the biaxially stretched film of the polyester composition of the present invention is preferably 0.1 to 10.0 μm, more preferably 0.3 to 7.0 μm, and particularly preferably 0.5 to 5 μm. It is 0.0 μm. The thinner the film is, the shorter the heat conduction distance is, and the perforation property is improved in the low heat application energy region. However, if it is less than 0.1 μm, the print clarity is apt to be deteriorated, and the productivity and the winding workability in the film production are improved. May worsen. On the other hand, when the film thickness exceeds 10.0 μm, the perforation property is deteriorated and the printing clarity is deteriorated, and the film for heat-sensitive stencil printing suitable for the purpose of the present invention may not be reached.

The film may have a structure of two or more layers, and particles or other additives may be added to either layer. At that time, each layer may be coextruded, or may be formed into a film by an extrusion laminating method or a coating method. Also,
In order to improve the adhesiveness between the film and the porous support, the surface of the film may be subjected to corona discharge treatment in air, carbon dioxide gas and nitrogen gas, or a mixed gas thereof.

The polyester film in the present invention is
The average thermal shrinkage in the longitudinal direction and the transverse direction at 120 ° C. is preferably 5 to 80%, more preferably 10
˜70%, more preferably 10 to 60%. If the average heat shrinkage ratio is less than 5%, the perforation property is poor and the printing sharpness is further deteriorated, which is not preferable. On the other hand, if the average heat shrinkage exceeds 80%, curling occurs after perforation and the printing sharpness is deteriorated, and the film for heat-sensitive stencil printing paper suitable for the purpose of the present invention may not be achieved.

The biaxially stretched film of the present invention can be formed by any conventionally known method. For example, it can be obtained by drying the polyester composition of the present invention, then melt-extruding it to obtain an unstretched sheet, then biaxially stretching it and further heat-treating it. Biaxial stretching may be either longitudinal or transverse sequential stretching or simultaneous biaxial stretching, and the stretching ratio is not particularly limited, but usually 2.0 to 5.0 times both longitudinal and transverse are suitable. . Alternatively, it may be stretched in the machine direction or in the transverse direction after stretching in the machine direction or in the transverse direction.

The obtained film is heat-treated, but if necessary, it may be stretched in the machine direction and / or the transverse direction before or after the heat treatment. The heat treatment temperature is 70 to 180
℃ is preferred, more preferably 90 ~ 150 ℃,
The heat treatment time is usually 1 second to 5 minutes. The heat shrinkage rate can be adjusted under this heat treatment condition. Further, the cooling rate of the film after the heat treatment also affects the heat shrinkage property.

The film may be coated if necessary. By providing a release layer by coating, antistick property and adhesion prevention with the manuscript are provided, and by providing an adhesive layer, adhesion with a porous support is provided, or antistatic property is provided. Good. As the coating, water-soluble, emulsified or suspended is used from the viewpoint of explosion proof and environmental pollution, and it is applied to a biaxially stretched film after completion of crystal orientation or after stretching after application to a film before completion of crystal orientation. There is a way to do it. The coating method is not particularly limited, but it is preferable to use a roll coater, a gravure coater, a reverse coater, a kiss coater, a bar coater or the like.

Before coating, if necessary, the coated surface may be subjected to corona discharge treatment in various atmospheres. Further, the coating layer may contain a defoaming agent, a cross-linking agent, a thickening agent, various particles, a lubricant, an antioxidant, a dye, a pigment and the like, if necessary.

[0034]

EXAMPLES The present invention will now be described in more detail by way of examples. The thermal properties of the polyester composition, the heat shrinkage ratio of the film, and the properties of the heat-sensitive stencil printing base paper in the examples were measured and evaluated by the following methods.

A. Thermal Properties of Polyester Composition (Glass Transition Point: Tg, Melting Point: Tm) Using DSC-2 type manufactured by Perkin-Elmer Co., Ltd., 10 mg of polyester was heated at a heating rate of 16 ° C./min under a nitrogen stream and measured. On the other hand, the polyester whose melting point is not obtained under the above conditions was treated with heated water at 90 ° C. for 5 hours, vacuum dried at room temperature for 24 hours, and then the melting point was determined.

B. A film sample having an average heat shrinkage of 100 mm square was measured at a predetermined temperature (120
After immersing in silicone oil set to ℃) for 1 minute,
The amount of shrinkage in the machine direction and the transverse direction of the film was calculated, the ratio to the original size was calculated as a percentage, and the average value was calculated.

C. Characteristics of heat-sensitive stencil printing base paper The obtained film was laminated on a porous support (Japanese paper) to prepare a base paper, and a character image and 1 were applied by a thermal head at applied energy of 0.09 mJ and 0.12 mJ.
6-level gradation image was prepared. The state of perforation in the gradation image area was observed with a microscope from the film side of the plate-making base paper, and the perforation characteristics were evaluated by the following items.

(1) Perforation sensitivity ⊚: The predetermined perforation was surely performed and was good. ◯: There was a part where a predetermined perforation could not be obtained, but there was no problem in practical use. Δ: There were portions where the desired perforations could not be obtained. X: The predetermined perforation cannot be obtained at all.

(2) Independent perforation ⊚: Each dot was independently perforated and was good. ◯: There was a portion in which a dot was not independently punched for each dot, but there was no problem in practical use. Δ: There were portions where dots were not independently punched. X: There are many places where dots are not independently punched or where adjacent dots are connected. In addition, the following characteristics of the characters and images (solid printing) of the printed matter were visually evaluated for the printing clarity using the plate making base paper.

(3) Visibility of character printing ◯: No missing of characters or uneven thickness. B: Although there are missing characters and uneven thickness, there is no practical problem. X: Unusable due to missing characters and uneven thickness.

(4) Clarity of solid printing ● (circle filled in black) 0.5.
The base papers of 0, 3.0, 10.0 and 30.0 mmφ were evaluated as follows. Evaluation of compatibility with solid paper size of solid printing Evaluation of uneven density of solid printing ○: No problem. Δ: There was a problem in a very small part, but there was no problem in practical use. X: Clearly problematic and unusable.

Example 1 77.3 parts by weight of dimethyl terephthalate, 13.6 parts by weight of dimethyl isophthalate, 58.1 parts by weight of ethylene glycol, 0.08 parts by weight of calcium acetate as a transesterification reaction catalyst, and as a polycondensation reaction catalyst Add 0.03 parts by weight of antimony trioxide, 0.1 parts by weight of Irganox 1010 (manufactured by Ciba Geigy) as an antioxidant, and 0.2 parts by weight of silicone TSF433 (manufactured by Toshiba Silicone Co., Ltd.) as an antifoaming agent. According to a conventional method, the theoretical amount of methanol was distilled out of the system while gradually raising the temperature from 150 ° C. to 240 ° C. to cause a transesterification reaction, and then 0.04 parts by weight of trimethyl phosphate and a number average molecular weight of 20,000 were used as a coloring inhibitor. Polyethylene glycol 10.0
Parts by weight were added. Then, the temperature was gradually raised from 240 ° C. and the pressure was reduced, and finally a polycondensation reaction was carried out at 285 ° C. and 1 mmHg or less to obtain a polyester composition having a glass transition point of 72 ° C. and a melting point of 212 ° C. Further, the obtained polyester composition was vacuum dried at 140 ° C. for 24 hours, then fed to an extruder, melted at 260 ° C., extruded in a sheet form from a T-type die, and cooled and solidified to obtain an unstretched film. Next, the unstretched film is heated to 100 ° C., stretched 3.5 times in each of the longitudinal and transverse directions, and subjected to heat treatment at 150 ° C. for 5 seconds,
After cooling, a biaxially stretched film having a thickness of 2.0 μm was obtained. Further, the obtained film was attached to a porous support to prepare a heat-sensitive stencil printing base paper, and the perforation characteristics and the printing sharpness were evaluated. The results are shown in Table 2. The perforation sensitivity, which is a perforation characteristic, was good because the predetermined perforation was surely performed. Furthermore, the independent perforation was good because each dot was independently perforated. In addition, the sharpness of character printing, which is the printing clarity, was free from missing characters and uneven thickness. Further, the sharpness of solid printing was good without any problem in correspondence with the size of the base paper and unevenness of light and shade.

Comparative Example 1 100 parts by weight of dimethyl terephthalate, 65 parts by weight of ethylene glycol, 0.09 parts by weight of calcium acetate as a transesterification reaction catalyst, and 0.03 parts by weight of antimony trioxide as a polycondensation reaction catalyst were added. Then, a theoretical amount of methanol was distilled out of the system while gradually raising the temperature from 150 ° C. to 240 ° C. to cause a transesterification reaction, and then 0.05 part by weight of trimethyl phosphate was added as a coloring inhibitor.
Then gradually increase the temperature from 240 ° C and reduce the pressure until the final 28
Polycondensation reaction was performed at 5 ° C. and 1 mmHg or less to obtain polyester having a glass transition point of 82 ° C. and a melting point of 256 ° C. Further, the obtained polyester was vacuum dried at 140 ° C. for 24 hours, then supplied to an extruder, melted at 290 ° C., extruded into a sheet form from a T-shaped die, and cooled and solidified to obtain an unstretched film. Next, the unstretched film was heated to 100 ° C., stretched 3.5 times in the longitudinal and transverse directions, heat-treated at 160 ° C. for 5 seconds, and cooled to obtain a biaxially stretched film having a thickness of 2.0 μm. . Further, the obtained film was laminated on a porous support to prepare a heat-sensitive stencil printing base paper, and the perforation characteristics and the printing sharpness were evaluated. The results are shown in Table 2. The perforation sensitivity, which is a perforation characteristic, did not give the desired perforation at all. Furthermore, independent perforation was not independently perforated for each dot. In addition, the sharpness of character printing, which is the printing clarity, was unusable due to missing characters and uneven thickness. Further, the sharpness of solid printing was unusable due to obvious problems with the compatibility with the size of the base paper and the uneven density.

Comparative Example 2 85.9 parts by weight of dimethyl terephthalate, 15.2 parts by weight of dimethyl isophthalate, 65 parts by weight of ethylene glycol and calcium acetate of 0.1% as a transesterification reaction catalyst.
09 parts by weight and 0.03 parts by weight of antimony trioxide as a polycondensation reaction catalyst were added, and the theoretical amount of methanol was distilled out of the system while gradually raising the temperature from 150 ° C. to 240 ° C. according to a conventional method to cause a transesterification reaction. After that, 0.05 part by weight of trimethyl phosphate was added as a coloring inhibitor. Then, gradually increase the temperature from 240 ° C, reduce the pressure, and finally 285
Polycondensation reaction was carried out at a temperature of 1 ° C or less and 1 mmHg or less to obtain a polyester having a glass transition point of 75 ° C and a melting point of 214 ° C. Further, the obtained polyester was vacuum dried at 140 ° C. for 24 hours, then fed to an extruder, melted at 260 ° C., extruded in a sheet form from a T-type die, and cooled and solidified to obtain an unstretched film. Next, the unstretched film was heated to 100 ° C., stretched 3.5 times in the longitudinal and transverse directions, heat-treated at 150 ° C. for 5 seconds, and cooled to obtain a biaxially stretched film having a thickness of 2.0 μm. . Further, the obtained film was laminated on a porous support to prepare a heat-sensitive stencil printing base paper, and the perforation characteristics and the printing sharpness were evaluated. The results are shown in Table 2. As for the perforation sensitivity, which is a perforation characteristic, there were portions where the desired perforation could not be obtained. Furthermore, in the independent perforation, there were portions where dots were not independently perforated. In addition, the sharpness of character printing, which is the printing clarity, was unusable due to missing characters and uneven thickness. Further, the sharpness of solid printing was unusable due to obvious problems with the compatibility with the size of the base paper and the uneven density.

Examples 2-9 , Reference Examples As shown in Table 1, Examples 2-9 , Reference Examples are acid components,
Type of glycol component, the amount changes and the molecular weight of the polyoxyalkylene glycol, except for changing the content, to obtain a variety of polyester and film in the same manner as in Example 1. The results are shown in Table 2. Examples 2 to 9 were within the scope of the present invention, and both the perforation characteristics and the printing sharpness were good, and there was no problem in practical use.

[0046]

[Table 1]

[Table 2]

[0047]

The polyester composition and film for heat-sensitive stencil printing base paper having excellent perforation properties (perforation sensitivity, independent perforation) in the low heat application energy region and excellent printing sharpness (character printing, solid printing).

Front page continued (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41N 1/24 102 C08L 67/02 C08J 5/18 B29K 67:00

Claims (6)

(57) [Claims] 1. At least one or more acid components selected from aromatic dicarboxylic acids, aliphatic dicarboxylic acids and / or alicyclic dicarboxylic acids, and aliphatic glycols having 2 to 10 carbon atoms and / or 6 to 16 carbon atoms. Is a polyester composed of at least one glycol component selected from alicyclic glycols, and has a number average molecular weight of 600.
20 The 0-1100000 poly ethylene glycol component
For heat-sensitive stencil printing base paper characterized by containing less than wt% for heat-sensitive stencil printing base paper
Film . 2. The film for heat-sensitive stencil printing base paper according to claim 1, wherein the polyester composition has a melting point of 270 ° C. or lower. 3. The film for heat-sensitive stencil printing base paper according to claim 1, wherein the melting point of the polyester composition is 100 ° C. or higher. 4. The polyester comprises ethylene glycol, 1, and at least one acid component selected from terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid.
The film for heat-sensitive stencil printing paper according to any one of claims 1 to 3, which comprises at least one glycol component selected from 4-cyclohexanedimethanol. 5. The polyester according to claim 1, wherein the polyester comprises an acid component of terephthalic acid and isophthalic acid and a glycol component of ethylene glycol.
A film for heat-sensitive stencil printing base paper according to item. 6. A thickness of the polyester composition of 0.1.
A biaxially stretched film of 10 .mu.m, serial be vertical and horizontal average heat shrinkage is 5% to 80% in any one of claims 1 to 5, wherein at 120 ° C. <br /> Film for heat-sensitive stencil printing base paper.