JPH06179741A - Polyester and film for base paper for heat-sensitive stencil printing - Google Patents

Abstract

PURPOSE:To obtain a polyester for heat-sensitive stencil printing base paper, comprising an acid component composed of an aromatic dicarboxylic acid, etc., and a glycol component composed of an aliphatic glycol, etc., having a specific melting point, excellent in perforating properties by heat and brightness in printing and useful for facsimile, etc. CONSTITUTION:The objective polyester comprises a principal acid component composed of an aromatic dicarboxylic acid and/or an alicyclic dicarboxylic acid (preferably terephthalic acid, isophthalic acid or 2,6-naphthalenedicarboxylic acid) and a principal glycol component composed of a 6-10C aliphatic glycol and/or a 6-l6C alicyclic glycol (preferably 1,6-hexandiol or 1,4- cyclohexandimethanol) and has 100-220 deg.C (preferably 150-200 deg.C) melting point. Furthermore, a titanium compound is preferably used as a reaction catalyst in an amount of 0.001-0.05wt.% based on the resultant polyester.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to polyesters and films for heat-sensitive stencil printing base paper. More specifically, the present invention relates to a polyester and a film for heat-sensitive stencil printing paper which is perforated by heat, and more specifically to a polyester and a film for heat-sensitive stencil printing paper which is excellent in heat perforation and sharpness at the time of 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.
As the film for heat-sensitive stencil printing base paper, films of various resins such as vinyl chloride, vinylidene chloride copolymer, polypropylene and polyester have been used.

However, the current heat-sensitive stencil printing base paper has been punched by the high heat application energy of the thermal head and put into practical use. However, the high heat causes a short life of the thermal head. Further, since commercially available facsimiles, word processors and the like are thermal heads with low heat application energy, they have a drawback that they are inferior in perforation property and lack in sharpness during printing.

Many proposals have been made to solve such problems. For example, as a film excellent in perforation property under low heat application energy, there are disclosed in JP-A-2-158391 and JP-A-4-173835, a film containing polybutylene terephthalate as a main component and JP-A-62-162.
No. 282983, JP-A-62-149496 and JP-A-62-253492 disclose thermal characteristics,
Films and the like having specified heat shrinkage properties have been proposed.

[0005]

However, in the above-mentioned prior art, there are drawbacks such as poor perforation property under low heat application energy, enlargement of perforation diameter, clogging, and lack of sharpness at the time of printing. is there.

An object of the present invention is to eliminate these drawbacks, and to provide a polyester and a film for heat-sensitive stencil printing base paper, which are excellent in perforating property under low heat applied energy and excellent in sharpness at the time of printing.

[0007]

The object of the present invention described above is such that the main acid component is an aromatic dicarboxylic acid and / or an alicyclic dicarboxylic acid, and the main glycol component is a carbon atom having 6 carbon atoms.
-10 aliphatic glycol and / or 6 to 1 carbon atoms
6 alicyclic glycol and has a melting point of 100 to 22
This can be achieved by polyester and film for 0 ° C. heat sensitive stencil.

The polyester in the present invention means that the main acid component is an aromatic dicarboxylic acid and / or alicyclic dicarboxylic acid, and the main glycol component is an aliphatic glycol having 6 to 10 carbon atoms and / or a fat having 6 to 16 carbon atoms. A polyester having a cyclic glycol as a constituent component, examples of the aromatic dicarboxylic acid component include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, phthalic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid and the like, or ester-forming derivatives thereof. Or 5-
Examples thereof include ester-forming sulfonic acid alkali metal salt compounds such as sodium sulfoisophthalic acid, and examples of the alicyclic dicarboxylic acid component include 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1, 4-cyclohexane dicarboxylic acid, decalin dicarboxylic acid, etc. can be mentioned. Among them, terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid are preferable as the acid component from the viewpoint of thermal piercing property. These acid components may be used alone or in combination of two or more. Examples of the aliphatic glycol component having 6 to 10 carbon atoms include 1,6-hexanediol, 1,
7-heptanediol, 1,8-octanediol,
Examples thereof include 1,9-nonanediol and 1,10-decanediol. Examples of the alicyclic glycol component having 6 to 16 carbon atoms include 1,2-cyclohexanedimethanol and 1,3-cyclohexanedimethanol. , 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-tetraoxa (5,5) undecane and the like can be mentioned. Among them, 1,6-hexanediol and 1,4-cyclohexanedimethanol are preferable as the glycol component from the viewpoint of thermal piercing property.
These glycol components may be used alone or in combination of two or more.

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 oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid,
Aliphatic dicarboxylic acids such as maleic acid and fumaric acid, oxycarboxylic acids such as p-oxybenzoic acid, trimellitic acid,
Polyfunctional compounds such as trimesic acid and trimethylolpropane, ethylene glycol, propanediol, butanediol, pentanediol, neopentyl glycol,
Examples thereof include aliphatic glycols such as diethylene glycol, aromatic glycols having a phenol nucleus, a bisphenol nucleus, a naphthalene nucleus, and polyoxyalkylene glycols such as polyethylene glycol.

In the polyester of the present invention, the melting point of the polyester is 100 to 2 in order to improve the thermal piercing property.
It is necessary to set the temperature to 20 ° C., preferably 130 to 2
The temperature is 10 ° C, more preferably 150 to 200 ° C. When the melting point is less than 100 ° C., the perforation diameter is enlarged or clogged by the storage heat energy after the applied perforation, so that the print definition is lowered. On the other hand, if the melting point exceeds 220 ° C., at low heat application energy, the perforation property and print definition are inferior, so that a film for heat-sensitive stencil sheet suitable for low heat application energy, which is the object of the present invention, cannot be reached. The polyester of the present invention having such a melting point is obtained by appropriately changing the type or composition of the acid component and / or glycol component constituting the polyester, or by using two or more types of acid component and / or glycol component in combination. It is possible and is not particularly limited.

For example, at least one acid component selected from terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid as constituent components of polyester and 1,6-
Polyester consisting of at least one glycol component selected from hexanediol and 1,4-cyclohexanedimethanol is preferable, and further 30 to 100 mol% of terephthalic acid and / or 2,6-naphthalenedicarboxylic acid and isophthalic acid are used as acid components. Acid 0 to 70 mol%, 1,6-hexanediol 5 as glycol component
Of 100 to 100 mol% and 1,4-cyclohexanedimethanol of 0 to 95 mol% is preferable, and especially 50 to 100 mol% of terephthalic acid and / or 2,6-naphthalenedicarboxylic acid and isophthalic acid of 0 to 0 are used as acid components. A polyester composed of 50 mol% and 20 to 100 mol% of 1,6-hexanediol as a glycol component and 0 to 80 mol% of 1,4-cyclohexanedimethanol is preferable.

The polyester of the present invention can be produced by any conventionally known method and 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 performed at high temperature and under reduced pressure.

As a concrete polyester of the present invention, for example, a method for producing a polyester comprising terephthalic acid as an acid component and 1,6-hexanediol and 1,4-cyclohexanedimethanol as a glycol component will be described. , 6-hexanediol and 1,4-cyclohexanedimethanol are directly esterified, or dimethyl terephthalate and 1,
A first stage reaction in which 6-hexanediol and 1,4-cyclohexanedimethanol are transesterified, and a second stage reaction in which the reaction product of this first stage is polycondensed
And a method of manufacturing the same.

The polycondensation reaction temperature at this time is 270 to 29.
When the temperature is 0 ° C., the reactivity of the deglycolization reaction is good, the thermal stability is excellent, and a polyester having a high polymerization degree can be obtained, which is preferable.

Further, in producing the polyester of the present invention, a reaction catalyst such as a metal compound and a coloring preventing agent such as a phosphorus compound can be appropriately used. Examples of such a reaction catalyst include alkali metal compounds, alkaline earth metal compounds, zinc compounds, lead compounds, manganese compounds, cobalt compounds, aluminum compounds, germanium compounds, antimony compounds and titanium compounds. Among them, the use of a titanium compound as an esterification reaction or transesterification reaction catalyst, and further as a polycondensation reaction catalyst is preferable in that a transparent polyester having a high degree of polymerization can be obtained. The type of titanium compound is not particularly limited, for example, tetramethyl titanate, tetrabutyl titanate or titanium tetrachloride,
Examples thereof include lithium titanate, potassium salt or magnesium salt of fluorotitanic acid, ammonium oxalate titanate, potassium potassium oxalate, tetrabenzoic acid titanate, tetrahydroxyethyl titanate or tetrastearyl titanate, and hydrolysates thereof. Alternatively, a derivative can also be used. Of these, tetrabutyl titanate and tetrahydroxyethyl titanate are preferable because they are excellent in thermal stability and a polyester having a high degree of polymerization can be obtained. Further, these may be used in combination of two or more kinds. From the viewpoint of reactivity, the amount of the titanium compound used is preferably 0.0001 to 0.3% by weight, more preferably 0.0005 to 0.1% by weight, and even more preferably 0.001 to 0% by weight based on the polyester obtained. It is 0.05% by weight. Further, as a reaction catalyst other than the titanium compound, a conventionally known alkali metal, alkaline earth metal or a metal compound such as manganese, cobalt, zinc, lead, aluminum, antimony or germanium may be used in combination. Further, examples of the phosphorus compound include phosphoric acid, phosphorous acid, phosphonic acid and derivatives thereof. Two or more of these may be used in combination.

The polyester of the present invention may optionally contain
An antioxidant, an antistatic agent, a weather resistance agent, a terminal blocking agent, etc. may be added, and clay for the purpose of imparting slipperiness,
Inorganic particles such as mica, titanium oxide, calcium carbonate, kaolin, wet and dry process silica, colloidal silica, calcium phosphate, barium sulfate and alumina.
Furthermore, you may mix | blend the organic particle etc. which have acrylic acid, styrene, etc. as a structural component.

Further, conventionally known polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate may be blended.

The polyester film in the present invention is
Although it may be an unstretched sheet or a uniaxially or biaxially stretched film, a biaxially stretched film is preferable.

The polyester film of the present invention can be formed by any conventionally known method. For example, in the case of a biaxially stretched film, it is obtained by first drying the polyester of the present invention, then melt-extruding it to obtain an unstretched sheet, then stretching it biaxially and further subjecting it to heat treatment. 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 thickness of the obtained biaxially stretched film is preferably 0.1 to 10.0 μm, more preferably 0.5 to 5.0 μm, and particularly preferably 1.0 to
It is 3.5 μm.

[0020]

EXAMPLES The present invention will now be described in more detail by way of examples. The polyester and film heat sensitive stencil characteristics in the examples were measured and evaluated by the following methods.

A. Melting Point (Tm) of Polyester Using DSC-2 type manufactured by Perkin-Elmer Co., Ltd., the temperature was measured at 10 mg of polyester at a heating rate of 16 ° C./min.

B. Characteristics of stencil printing base paper The obtained film is attached to a support to create a base paper,
The applied energy was applied by a thermal head to carry out perforation plate making, actual printing was carried out using a printing machine, and the obtained characters and images were judged.

(1) Applied Energy The value when the appropriate perforated applied energy of the polyester film of Reference Example 1 was taken as 100% was measured. ◯: Applied energy is less than 80% and is at a target practical level. B: Applied energy is 80% or more and less than 90%, which is almost at a practical level. X: The applied energy exceeds 90% and is not at a practical level.

(2) Perforability Perforability was evaluated by observing from the film side of the plate-making base paper with a microscope. ⊚: The desired perforation was 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 desired perforation cannot be obtained at all.

(3) Sharpness The print density of the printed matter was visually determined. ⊚: Clear printing was possible without unevenness in density, bleeding, and blurring, which was good. ◯: There was unevenness in shading, bleeding, and blurring, but the printing sharpness was at a practical level and was good. Δ: Partially uneven in shades, bleeding, and blurring, and somewhat inferior in sharpness. X: It was unclear that unevenness in shades, bleeding, and blurring were obvious.

Reference Example 1 85 parts by weight of dimethyl terephthalate, 15 parts by weight of dimethyl isophthalate, 65 parts by weight of ethylene glycol, 0.09 parts by weight of calcium acetate as a transesterification reaction catalyst, and 0.03 of antimony trioxide as a polycondensation reaction catalyst. By adding 1 part by weight, 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 0.05 part by weight of trimethyl phosphate was added as an anti-coloring agent. Was added. Next, the temperature is gradually raised from 240 ° C, the pressure is reduced, and finally 290 ° C, 1 mmHg.
Polycondensation reaction was performed below to obtain a polyester having a melting point of 225 ° C. Further, the obtained polymer was vacuum dried at 140 ° C. for 24 hours, then supplied to an extruder and melted at 290 ° C. and extruded in a sheet form from a T-shaped die to be cooled and solidified to obtain an unstretched film. The unstretched film is then 80
The film was heated to 120 ° C, stretched 3.3 times in the longitudinal and transverse directions, and heat-treated at 160 to 240 ° C to obtain a biaxially stretched film having a thickness of 2.0 µm. Further, the obtained film was attached to a support to prepare a heat-sensitive stencil printing base paper, and the heat perforation property and printing characteristics were evaluated. The results are shown in Table 2. The applied energy was 100%, and the piercing property was in places where a predetermined piercing was not obtained. The print sharpness was slightly inferior in terms of uneven density, bleeding, and blurring in some areas.

Example 1 As dimethyl terephthalate 74.3 parts by weight, 1,6-hexanediol 67.8 parts by weight, 1,4-cyclohexanedimethanol 27.6 parts by weight, as a transesterification reaction catalyst and polycondensation reaction catalyst Tetrabutyl titanate 0.0
Add 2 parts by weight and gradually increase from 150 ° C to 240
While raising the temperature to ℃, the theoretical amount of methanol was distilled out of the system for transesterification. Then, the temperature was gradually raised from 240 ° C. and the pressure was reduced, and finally a polycondensation reaction was carried out at 280 ° C. and 1 mmHg or less to obtain a polyester having a melting point of 162 ° C. Further, the obtained polyester was vacuum dried at 120 ° C. for 24 hours, then supplied to an extruder, melted at 220 ° C., extruded in a sheet form from a T-type die, and cooled and solidified to obtain an unstretched film. The unstretched film is then 90
It is heated to ℃ and stretched 3.3 times in the longitudinal and transverse directions, respectively.
Heat treatment was performed at 00 ° C. to obtain a biaxially stretched film having a thickness of 2.0 μm. The obtained film was attached to a support to prepare a heat-sensitive stencil printing base paper, and the heat perforability and printing characteristics were evaluated. The results are shown in Table 2. Applied energy is 70-8
At 0%, the perforability was good because the desired perforation was performed.
In addition, the printing sharpness was good, with no unevenness in density, bleeding, and blurring, and clear printing was possible.

Example 2 78.2 parts by weight of dimethyl terephthalate, 95.2 parts by weight of 1,6-hexanediol, 0.02 part by weight of tetrahydroxyethyl titanate as a transesterification reaction catalyst and polycondensation reaction catalyst were added, and According to the method, the theoretical amount of methanol was distilled out of the system while the temperature was gradually raised from 150 ° C. to 240 ° C. to carry out a transesterification reaction. Then 240
Gradually increase the temperature from ℃, reduce the pressure, and finally 280 ℃, 1mm
Polycondensation reaction was carried out at Hg or less to obtain a polyester having a melting point of 148 ° C. Furthermore, the obtained polyester is heated to 100 ° C.
After vacuum drying for 48 hours, feed it to the extruder and
It was melted at 0 ° C., extruded in a sheet form from a T-shaped die, and cooled and solidified to obtain an unstretched film. Then, the unstretched film was heated to 90 ° C., stretched 3.3 times in each of the longitudinal and transverse directions, and heat-treated at 100 ° C. to obtain a biaxially stretched film having a thickness of 2.0 μm. Further, the obtained film was attached to a support to prepare a heat-sensitive stencil printing base paper, and the heat perforation property and printing characteristics were evaluated. The results are shown in Table 2. The applied energy was less than 80%, and the piercing property was at a level where practically no problem occurred although there was a portion where a predetermined piercing was not obtained. Further, the printing sharpness was good because it was practically used, although unevenness in shading, bleeding, and blurring were present in a small part.

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, the temperature is gradually raised from 240 ° C., the pressure is reduced, and finally 29
Carry out polycondensation reaction at 0 ° C and 1 mmHg or less, melting point 25
8 ° C. polyester was obtained. Furthermore, the obtained polymer is 1
After vacuum drying at 40 ° C for 24 hours, it is fed to an extruder and melted at 290 ° C and extruded into a sheet from a T-shaped die,
An unstretched film was obtained by cooling and solidifying. Then, the unstretched film was heated to 100 ° C., stretched 3.3 times in each of the longitudinal and transverse directions, and heat-treated at 210 ° C. to obtain a biaxially stretched film having a thickness of 2.0 μm. Further, the obtained film was attached to a support to prepare a heat-sensitive stencil printing base paper, and the heat perforation property and printing characteristics were evaluated. The results are shown in Table 2. Even when the applied energy was 100% or more, the perforability could not be the predetermined perforation, and the print sharpness was unclear because of uneven density, blurring, and blurring.

Examples 3 to 10 and Comparative Example 2 As shown in Table 1, various polyesters and films were obtained in the same manner as in Example 1 except that the types and amounts of the acid component and glycol component were changed. The results are shown in Table 2. Examples 3 to 10 were within the scope of the present invention, and were good in applied energy, perforation property, and print clarity. On the other hand, Comparative Example 2 had a melting point outside the range of the present invention, and was inferior in perforation property and print clarity.

Comparative Example 3 79.4 parts by weight of dimethyl terephthalate, 8.8 parts by weight of dimethyl isophthalate, 81.9 of 1,4-butanediol.
By weight, 0.1 part by weight of tetrabutyl titanate as a transesterification reaction catalyst and polycondensation reaction catalyst was added, and a theoretical amount of methanol was distilled out of the system according to a conventional method while gradually increasing the temperature from 150 ° C to 220 ° C. Exchange reaction was performed. Then, gradually reduce the pressure at 240 ° C to 1 m.
Polycondensation reaction was performed at mHg or less to obtain a polyester having a melting point of 210 ° C. The obtained polymer was vacuum dried at 120 ° C. for 24 hours, then fed to an extruder and melted at 260 ° C., extruded into a sheet form from a T-type die, and cooled and solidified to obtain an unstretched film. Then, the unstretched film is heated to 60 ° C.
And draw it 3.3 times in the longitudinal and transverse directions.
Heat treatment was performed at 0 ° C. to obtain a biaxially stretched film having a thickness of 2.0 μm. Further, the obtained film was attached to a support to prepare a heat-sensitive stencil printing base paper, and the heat perforation property and printing characteristics were evaluated. As a result, the applied energy was less than 80%, but the perforability was smaller than the predetermined perforation diameter. Since the printing sharpness was smaller than that of the predetermined hole, unevenness in shades, bleeding, and blurring were partially present, and the sharpness was slightly inferior.

[0032]

[Table 1]

[Table 2]

[0033]

EFFECTS OF THE INVENTION A polyester and a film for heat-sensitive stencil printing base paper, which have excellent perforation properties in the low heat application energy range of facsimiles, word processors and the like and have excellent sharpness at the time of printing.

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Claims (3)

[Claims] 1. A main acid component is an aromatic dicarboxylic acid and / or an alicyclic dicarboxylic acid, and a main glycol component is an aliphatic glycol having 6 to 10 carbon atoms and / or an alicyclic glycol having 6 to 16 carbon atoms. And melting point 10
Polyester for heat-sensitive stencil printing base paper at 0-220 ° C. 2. A main acid component is at least one selected from terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid, and a main glycol component is selected from 1,6-hexanediol and 1,4-cyclohexanedimethanol. The polyester for heat-sensitive stencil printing base paper according to claim 1, which comprises at least one kind of 3. A film comprising the polyester for heat-sensitive stencil printing base paper according to claim 1.