JPH0733118B2 - Method for producing high mesh / high modulus polyester screen gauze - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a screen gauze made of a high mesh / high modulus polyester monofilament suitable for screen printing of electronic circuits and the like, and more specifically, as a gauze. By weaving a gauze from a specific high-modulus polyester monofilament suitable for post-processing, and then stretching and heat-setting the gauze, a high-quality high-mesh high-quality product with excellent dimensional stability and opening uniformity is obtained. The present invention relates to a method for manufacturing a modulus screen gauze.

[Conventional technology]

In recent years, not only in the printing field of various electronic circuits, but also in other printing fields, screen printing is a printing method that is simple and excellent in productivity as compared with other printing technologies,
The spread is remarkable.

As the constituent fibers of the conventional screen gauze used for such screen printing, there are many fibers such as natural fibers such as silk, inorganic fibers such as stainless steel, and synthetic fibers such as nylon and polyester. Polyester monofilaments have been widely used because of their low cost and excellent properties such as dimensional stability for screen gauze.

However, in order to meet the recent strong demand for further improvement in printing accuracy in the field of printing electronic circuits,
It is necessary to provide a high-modulus screen gauze with a small denier of monofilant and a large opening area, good ink permeability, less dimensional change due to external force, less likely to break gauze, high strength and high modulus. is there. For example, the breaking strength of a gauze having a woven density of 305 mesh composed of monofilaments having a strength of 5 g / d is usually 28
~ 35Kg, modulus is about 16 ~ 18Kg, but with such strength, it is easy to break the gauze due to the high tension when the gauze is tensioned. Further, a higher modulus is required to enable high precision printing.

Generally, in order to obtain a high-strength, high-modulus, fine-denier polyester monofilament, there is a method of drawing a melt-spun unstretched monofilament at a high draw ratio. However, although the monofilament obtained by this method certainly has high strength, high modulus, and fine denier, the elongation is inevitably reduced, and it becomes rigid and hard, and the surface of the monofilament is regenerated by the reed during weaving. Scraping produces fiber scraps, and fibrous scum mainly composed of these fiber scraps is generated. Due to the generation of the fibrous scum, weaving becomes impossible, or even if weaving is possible, only a very low quality gauze into which the scum is woven can be obtained.

Therefore, in order to reduce the generation of such scum, for example, the generation of white powder scum, an amorphous, non-reactive polymer or silica gel or the like is contained in the polyester, and high strength having a fine unevenness on the surface, A high Young's modulus monofilament has been proposed (Japanese Patent Laid-Open No. 58-23936).
However, according to this method, since the amorphous and non-reactive polymer or silica gel is contained in the monofilament, the strength and elongation of the monofilament are lowered,
The strength, elastic recovery, and durability of the resulting screen gauze were reduced, and the performance of the screen gauze was not sufficiently satisfactory.

In addition, it is treated with a reactive silicone resin, and 0.1 to 0.7
A monofilament containing the resin by weight% has been proposed (JP-A-58-169540). In this case, a relatively small amount of the treating agent having a relatively high viscosity is uniformly attached to the surface of the monofilament. Is extremely difficult, and because the adhesiveness of the silicone resin that has undergone a crosslinking reaction on the surface of the polyester filament is insufficient, part of it peels off during warping or weaving and is woven into the screen gauze, degrading the quality of the gauze. Alternatively, there is a problem that the printing accuracy is deteriorated by peeling off during the finishing process of the screen gauze.

A filament in which a fine particle substance is attached to the filament surface or coated with an adhesive water-soluble resin together with the fine particle substance has been proposed (Japanese Patent Laid-Open No. 59-1164412), but a filament obtained by such a method is The coefficient of kinetic friction is reduced, and the smoothness is improved, but the fine particles do not adhere uniformly to the surface of the filament and the adhesive strength is insufficient. Was dropped and was woven into the screen gauze, degrading the quality of the screen gauze. Further, when a water-soluble resin is used, it is difficult to uniformly remove the particulate matter in the refining process of the screen gauze, and there is a problem that the opening accuracy of the high mesh screen gauze is lacking.

Further, JP-A-61-282424 discloses that the intrinsic viscosity is 0.7 to
1.2, Monofilament for screen gauze with high toughness, high modulus and improved fibrillarity on fiber surface, obtained from polyester with titanium oxide content of 0.1 wt% or less and carboxylic acid residue amount of 25 eq / 10 ⁶ or less However, since the monofilament has a low titanium oxide content, the coefficient of friction between the fiber surface and the metal is high, and the surface of the monofilament is scraped by the reed, and the problem of the occurrence of the fibrous scum is solved. Not only that, but also the obtained gauze has a drawback that the shavings generated during the weaving are woven and impair the quality of the gauze.

[Problems to be Solved by the Invention]

Therefore, the present inventors combined not only the characteristics of the polyethylene terephthalate monofilament used as the screen gauze but also the post-processing conditions of the gauze composed of the monofilament to obtain a dimensional stability, uniform opening, and high mesh. A method for producing a high-quality screen gauze suitable for high-precision screen printing with a high modulus, in particular, physical properties of the monofilament constituting the gauze, a fine structure centered on a polymer substrate or a crystalline structure, and post-processing conditions of the gauze. The present invention has been found by diligently studying the relationship.

That is, the object of the present invention enables high-precision printing, which has been strongly required in the field of electronic circuit printing, which could not be obtained by the above-described conventional method for producing a screen gauze using a high-strength polyester monofilament. It is an object of the present invention to provide a method for producing a high-strength, high-modulus screen gauze having a large area and excellent ink permeability and dimensional stability against external force.

[Means for Solving the Problems]

The object of the present invention is to obtain a modulus of 3.5-7.0 g / d and 1.358
High-strength monofilament made of polyethylene terephthalate having a density of 0 to 1.3750 g / cm ³ is woven to create a high-density gauze of at least 200 mesh, and then this gauze is 2 to 15% at least in the warp direction. It can be achieved by stretching at a stretching ratio of 1, and heat setting at a temperature of 160 ° C to 230 ° C.

The monofilament used in the present invention needs to have a modulus of 3.5 to 7.0 g / d measured according to the measuring method described later. This low-modulus monofilament is advantageous in improving weavability because it produces less fibrous scum. However, if the modulus is less than 3.5 g / d, the modulus of the gauze obtained is too low, so the stretch ratio in the post-processing of the gauze must be increased, and the gauze is broken during stretching and the opening is uniform. It is not preferable because it deteriorates the property and gives a gauze with a non-uniform mesh. On the other hand, the modulus is 7.
When it exceeds 0 g / d, fibrous scum is generated during weaving and is woven into the gauze, which deteriorates the quality of the gauze, which is not preferable.

Further, the monofilament used in the present invention has a density of 1.3580 to 1.3750 g / measured according to the measuring method described later.
It is important that it is in the range of cm ³ , and this density is preferably in the range of 1.3580 to 1.3700 g / cm ³ .
The lower the density, the smaller the progress of crystallization, the softer the obtained gauze, and the relatively high draw tension at the time of post-processing of the gauze makes it possible to draw with a high draw ratio,
A high modulus processed gauze with a uniform opening (that is, mesh) is obtained. However, the density is 1.3580
If it is less than g / cm ³ , the shrinkage of the gauze during heat setting is too large, and troubles such as breakage of the gauze occur during processing, which is not preferable. Also, the density is 1.3750
When it is larger than g / cm ³ , the stretching tension of the gauze becomes high, and the gauze breaks, which makes it difficult to uniformly stretch the gauze at a high stretch rate. It is not preferable because the opening becomes uneven.

Therefore, the monofilament used in the production of the difference of the present invention has, for example, a gauze having a breaking strength of 5.1 g / d or more, is stretched, and is heat-set to make the opening uniform. High mesh
When obtaining a high modulus processed gauze, it is important that its density is within the range of 1.3580 to 1.3750 g / cm ³ .

Next, in the present invention, a monofilament composed of polyethylene terephthalate satisfying the above-mentioned modulus and density is woven into a high mesh gauze of at least 200 mesh, and subsequently at a stretching ratio of 2 to 15% in at least the vertical direction of the gauze. It is necessary to stretch. If the weaving density before post-processing of the gauze is not at least 200 mesh or more, it becomes impossible to obtain a processed gauze of high mesh. The higher the weaving density, the easier it is to obtain a high-mesh gauze, but considering the ease of weaving, it is preferably 680 mesh or less, and more preferably in the range of 250 to 600 mesh. Good.

Further, when the stretch ratio of the gauze is less than 2%, the desired high-mesh processed gauze cannot be obtained. On the other hand, when it exceeds 15%, tearing tends to occur during the stretch of the gauze and before stretching. The density of the gauze must be increased, and in the case of a gauze with a high woven density, fibrous scum is generated during the weaving, which makes the weaving difficult.

Therefore, in the method for producing a screen gauze of the present invention, it is important to prepare a specific gauze from the specific monofilament specified in the present invention and process it under the above specific conditions. Only when both are satisfied at the same time, the processed gauze object of the present invention can be manufactured.

Here, as a method of stretching the gauze, in order to facilitate uniform stretching of the gauze and obtain a gauze with a high opening uniform, Tg-30 ° C to Tg + 50 ° C (Tg is a polyester It is desirable to preheat in the temperature range of (glass transition point).

The preheated gauze is stretched at least in the warp direction (the direction of pulling the warp yarn) of the gauze at a stretching ratio of 2 to 15%, but the stretching method is not particularly limited, and may be, for example, a supply roller. There is a general method of continuously stretching using a device equipped with a stretching roller and a method of fixing both sides of the gauze and stretching the gauze in the bamboo direction, and subsequently stretching the gauze in the horizontal direction.

Here, for example, in the case of stretching in the vertical direction, the stretch ratio means the number of weft threads per inch of the silk gauze before stretching is ₀ / inch, and the number of weft threads per inch of the stretched silk gauze is l. When the number is book / inch, it means a value represented by the formula [(l ₀ −l) / l ₀ ] −100.

In the present invention, in order to obtain a more uniform and high-mesh processed gauze, the stretching ratio is 3 to 10%, preferably 4 to
It is preferable that the range is 8%.

The gauze thus stretched is heat set at a temperature of 160 ° C to 230 ° C. As the heat setting means, there is generally a method of carrying out between a supply roller and a stretching roller, but a method of temporarily stretching and then heat setting may be adopted.

If the heat setting temperature is lower than 160 ° C., the heat setting of the gauze is insufficient, the secular change after the gauze is stretched is large, the dimensional stability is deteriorated, and the printing resistance is deteriorated, which is not preferable. . Then, as the heat setting temperature becomes higher, the secular change of the gauze becomes smaller, and the printing resistance and strength are also improved, but when it exceeds 230 ° C, it becomes close to the melting point of polyethylene terephthalate, and the monofilament constituting the gauze is cut. However, the gauze is likely to break, which is not preferable.

Considering the secular change of the gauze and the stability of post-processing, the heat setting temperature is more preferably in the range of 170 ° C to 200 ° C.

Further, the monofilament used in the present invention preferably has a crystal size in the (100) plane obtained by wide-angle X-ray diffraction described later in the range of 15 to 32 angstroms, more preferably 20 to 30 angstroms. Such a crystal size is closely related to the dimensional stability of the processed gauze obtained from the monofilament. That is,
The smaller the crystal size of the monofilament, the greater the number of microcrystals that serve as nuclei. Therefore, during the heat setting of the gauze, crystallization progresses centering on the microcrystals, resulting in dimensional stability of the obtained processed gauze. Strengthen and improve. In particular, when the crystal size is 15 angstroms or more, the melting of fine crystals is reduced during preheating before stretching the gauze, which is advantageous.

However, when a gauze composed of monofilaments having a crystal size in such a size range is stretched and heat set, for example, even if the heat setting temperature is 165 ° C, 175
A processed gauze having dimensional stability and strength corresponding to a heat setting temperature of ℃ to 185 ℃ can be obtained.

Further, the monofilament of the present invention has a breaking strength of 4.
It is desirable to be in the range of 8 g / d to 8.0 g / d. If the breaking strength of the monofilament is 4.8 g / d or more, it is possible to prevent the gauze from breaking even when stretching a gauze having an extremely thin wire diameter. However, the breaking strength becomes too large, and if it exceeds 8.0 g / d, the monofilament surface is easily scraped by the reed during weaving, which is not preferable.

The breaking elongation of the monofilament is 35% at 15% or more.
It should be within the range not exceeding. The lower this breaking elongation, the higher the modulus of the monofilament,
The surface of the monofilament is easily scraped by the reed during the weaving, which is not preferable. When the breaking elongation is 15% or more,
Scraping of the monofilament due to the reed during weaving is extremely reduced, and a high-quality processed gauze is easily obtained. On the other hand, if the breaking elongation is large, it is necessary to stretch the gauze at a higher stretching rate, and it becomes difficult to obtain a uniform high-mesh processed gauze.

The monofilament of the present invention has a weaving degree of 5 to 30 denier, preferably 6 to 20 denier. The reason for this is that the finer the weaving, the more the opening area can be obtained, but the tearing tends to occur when the gauze is stretched. It is not preferable because the processed gauze has decreased.

The polyester in the present invention is a polyester whose main object is polyethylene terephthalate. More specifically, it is a polyester containing ethylene terephthalate as the main repeating unit, but terephthalic acid (TP
A) and ethylene glycol (EG) other than phthalic acid, adipic acid, sebacic acid, oxalic acid and other dicarboxylic acids, propylene glycol, butanediol, polyethylene glycol, polytetramethylene glycol and other diols, or 5-sodium It may be a monofilament made of polyester in which a small amount (usually 20 mol% or less) of a third component such as sulfoisophthalic acid is copolymerized and / or mixed.

Further, for the purpose of preventing halation and improving weavability, a polymer containing fine particles of titanium dioxide, silicon dioxide, or the like, or particles generated in the polymer in the polymer manufacturing process, that is, a polymer containing internal particles may be used. . In particular, the monofilament used in the present invention preferably contains titanium dioxide particles, and the addition amount thereof is preferably in the range of 0.2 to 0.7%. The titanium dioxide particles can be dispersed extremely uniformly in the polyester by applying a known dispersion technique. By forming uniform fine recesses on the fiber surface by this, it is possible to reduce the friction coefficient of the fiber, when weaving a monofilament having a modulus defined in the present invention,
It is possible to effectively prevent the occurrence of abrasion on the reed. In particular, if the amount of titanium dioxide particles added is 0.2% or more, the reed will not be scraped. Further, by setting the addition amount of the titanium dioxide particles to 0.7% or less, it is possible to uniformly disperse the titanium dioxide particles in the polymer, it is possible to prevent the formation of coarse particles, the surface of the monofilament Uniform and minute recesses are formed, and scraping on the reed does not occur.

Further, in order to prevent halation due to exposure to ultraviolet rays in the screen plate making process, a polymer containing an ultraviolet absorber can be used as the polyester for producing the monofilament.

The degree of polymerization of the polyester is such that the intrinsic viscosity measured with an o-chlorophenol solution at 35 ° C. is 0.5 or more, preferably 0.7 to
1.4 is suitable. Further, a polymer containing an ultraviolet absorber may be used in order to prevent halation during exposure to ultraviolet light in the screen plate making process.

The monofilament of the present invention is usually obtained by extruding a polymer from a pressure melt type or extruder type melt spinning machine, applying an oil agent to prepare an unstretched monofilament or an unstretched monofilament with a degree of orientation, and further stretching with a heating device. It can be produced by stretching with a machine.

What is important here is that the density of the monofilament is the degree of polymerization of polyethylene terephthalate used, the type of copolymerization components such as isophthalic acid and sebacic acid, and their copolymerization ratio, as well as the spinning speed, the heat setting temperature and time during stretching. However, the type of polymer to be used and the spinning / drawing conditions should be appropriately selected and determined so that a monofilament satisfying the density range specified in the present invention can be obtained. For example, the stretching temperature of the unstretched monofilament is 90 ° C to 120 ° C, the heat setting temperature is relatively low, and 90 ° C to 160 ° C and 0.1 to 0.3 seconds are appropriate. The crystal size depends on the polymer used, the cooling conditions and winding speed during spinning, the heat setting temperature during stretching, and the tension during heat setting, but cannot be generally stated, but the requirements specified in the present invention are satisfied. The conditions are appropriately selected and determined so that a monofilament to be obtained can be obtained. For example, the temperature of the monofilament at the time of winding is adjusted to 120 ° C to 160 ° C at a point 1 m below the spinneret, and the tension at the time of heat setting during stretching is set to be equal to or lower than the tension required for stretching. It is also possible to employ a direct drawing method in which after spinning, the film is continuously drawn without being once wound. Further, a method of producing a monofilament by spinning and spinning as a multifilament can also be adopted.

The modulus, breaking strength, breaking elongation, density and crystal size of the monofilament of the present invention were measured according to the following measuring methods.

Modulus, breaking strength, breaking elongation: The tensile strength when the tensile sample breaks at a test length of 20 cm and a speed of 20 cm / min by an Instron universal tensile tester in an atmosphere of a temperature of 20 ° C and a relative humidity of 65%. It is shown by the value divided by the denier before tensioning. The elongation at break of the sample was defined as the elongation at break. The modulus (g / d) was obtained by dividing the tension (g) at 10% elongation by the denier before stretching.

Density: Apparent density d'of the monofilament by a density gradient tube method using a density gradient consisting of carbon tetrachloride / n-heptane
Was calculated and the density d was calculated according to the following formula.

d = [d '(1-A / 100)] / {(1- (Axd') / 100B} In the above formula, A is the amount of additives (fine particles, etc.) other than the polymer contained in the polyester. (% By weight), and B is the density (g / cm ³ ) of additives (fine particles and the like) other than the polymer contained in the polyester.

Crystal size: Calculated according to Scherrer's formula below from the value of the peak half width of the surface index (100) obtained by the transmission method using a 4036 A2 wide-angle X-ray diffractometer manufactured by Rigaku Denki Co., Ltd.

L (100) = Kλ / β ₀ cos θ Correct, β ₀ ² = β _E ² = β ₁ ² , β _E = apparent half width, β ₁ = 1.05 × 10 ^-2 rad, K = 1.0, λ = X Line wavelength, θ = Bragg angle, L (100) = average size in the direction perpendicular to the (100) plane of the microcrystals, and this was expressed as a crystal size.

Further, the modulus, breaking strength, dimensional stability, and opening uniformity of gauze were evaluated by the following methods.

Modulus and breaking strength of gauze: JIS-L is used with a testing machine AG-B manufactured by Shimadzu Corporation.
According to -1068 (1979), using the labeled strip method, sample width 50 mm, gripping interval 200 mm, pulling speed 100 mm /
In minutes a tenacity-elongation curve was obtained. The strength at 10% elongation was defined as the modulus of the gauze, and the strength at break was the breaking strength of the gauze.

Dimensional stability: Using the Shimadzu Autograph SD-100, pull the sample to a width of 50 mm: gripping interval of 200 mm, tension speed of 10 mm / min up to a tension of 20 Kg, stop the tester as it is, and activate only the recording chart. Leave it for 20 minutes. The tension T ₂₀ (Kg) is read after 20 minutes have elapsed, and the change amount Y (%) is calculated from the following equation.

Y = [(20−T ₂₀ ) / 20] × 100 The smaller the amount of change Y, the better the dimensional stability and the printing resistance without the deterioration of the stretchiness with time and the dimensional change during printing.

If the amount of change Y is 81.0% or less, the dimensional stability is good.
Is 81.1% to 83.0%, the dimensional stability is slightly good, and the variation Y is 8
3.1% or more was defined as poor dimensional stability.

Uniformity of opening: Observe the processed gauze with a transmission microscope and check the opening distance (distance between adjacent warp threads and warp threads or weft thread and weft thread that form the gauze) for n = 100 The measurement was performed between the yarn and the warp yarn and between the weft yarn and the weft yarn, and the standard deviation was obtained for each. The smaller the obtained standard deviation was, the more uniform the opening was, and it was displayed as follows.

○: Good opening accuracy, ×: Poor opening accuracy.

In addition, the quality of the gauze was displayed according to the following criteria by observing the fibrous scum woven into the gauze.

○: The number of scum per 1 m of gauze was 0.2 or less and almost no fibrous scum was observed. ×: The number of scum per m of gauze was more than 0.2, and fibrous scum was recognized.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1 Polyethylene terephthalate containing 0.35% by weight of titanium dioxide was melt-spun by adjusting the discharge rate so that the drawn yarn fineness was 11.5 denier, and a finish oil was applied and wound up. The temperature of the yarn at 1 m below the spinneret was adjusted to 130 ° C to 150 ° C. The obtained unstretched monofilament was stretched with a stretching machine having a heating device at a stretching ratio of 3.7 times.

The obtained monofilament drawn yarn has a strength of 6 g / d and an elongation of 32.
%, Modulus 3.9 g / d, density 1.366 g / cm ³ , crystal size 23
It was Angstrom.

This monofilament was woven using a slewing loom after heat setting of gauze to adjust the woven density so that the woven density was 305 mesh. The occurrence of fibrous scum on the reeds during weaving was small, and the gauze was not woven with the fibrous scum. Further, the obtained gauze was preheated at 92 ° C. in advance and heat set at 180 ° C. while being stretched in the warp yarn direction at a stretching ratio of 6.7%.

The modulus of the gauze was compared before and after stretching. The modulus of the gauze in the warp direction after stretching is 6K before stretching.
28 g / g, and a high mesh / high modulus processed gauze with a good balance in the horizontal direction was obtained.

The processed gauze was a high-strength gauze with a breaking strength of 42 kg, and was extremely good in terms of dimensional stability, uniformity of opening, and quality of gauze. That is, this processed gauze was a high-modulus, high-mesh gauze consisting of fine denier monofilaments in which no fibrous scum was woven, and of high quality.

Example 2 In accordance with Example 1, the physical properties such as modulus and density shown in Table 1 were changed by changing the degree of polymerization, copolymerization ratio, discharge amount during spinning, take-up speed, draw ratio and temperature during drawing of the polymer used. Various drawn monofilaments having a single yarn fineness of 9 denier were obtained.

These drawn monofilaments were woven using a slewing loom after the heat setting of the gauze to adjust the woven density to 320 mesh. Furthermore, after stretching the gauze in the vertical direction and then in the horizontal direction so that the modulus of the obtained processed gauze is 24 kg, 165 ° C for No. 4 in Table 1
Then, all the samples other than No. 4 were heat set at 180 ° C.

Dimensional stability of the obtained processed gauze, uniformity of opening,
The quality of the gauze and the breakage of the gauze were evaluated and observed, and the results are shown in Table 1.

In Table 1, No. 1 had a low monofilament modulus, and therefore, in order to obtain a gauze having a high modulus, the stretch ratio had to be increased, and a considerable amount of gauze was broken. In addition, the obtained processed gauze had a poor opening uniformity and a non-uniform mesh. In No. 5, the monofilament had a high modulus and the gauze was woven with fibrous scum, and the quality of the gauze was poor. No. 6 has a high monofilament density, so the stretching tension of the gauze is high, making it difficult to stretch it uniformly, and uneven stretching occurs,
It was a processed gauze with uneven opening. In No. 7, the density of the monofilament was low, so the shrinkage during heat setting was too large and the gauze broke. Nos. 2, 3 and 4 were gauze satisfying the requirements of the present invention, and were high mesh and high modulus gauze having good dimensional stability, opening uniformity, gauze quality and gauze tear. . In addition, with No. 3
The crystal sizes (100) of No. 4 were 38 angstrom and 24 angstrom, respectively. 165 for No.4
Despite heat setting at a low temperature of ℃, a processed gauze having the same performance as that of heat setting at 180 ℃ was obtained.

Example 3 Using the monofilament of Example 1, the weaving density was adjusted so that the weave density of the gauze after heat setting was 320 mesh, and weaving was performed. No fibrous scum was woven into the obtained gauze. Subsequently, the gauze was post-processed by variously changing the stretching rate in both the vertical and horizontal directions and the temperature during heat setting. The processed gauze thus obtained was evaluated and observed for the modulus in both the vertical and horizontal directions, the dimensional stability, the uniformity of the opening, and the breaking of the gauze, and the results shown in Table 2 were obtained.

In Table 2, No. 8 had a low modulus, and thus the obtained gauze had a low modulus. Moreover, No. 12 had poor dimensional stability because the heat setting temperature was too low. Since No. 16 had a too large stretching rate, the gauze broke during stretching. In No. 14, the monofilament forming the gauze was partially melted and cut because the heat setting temperature was too high, and the gauze was broken. For these, the requirements of the present invention are satisfied. N
All of o.9,10,11,13 and 15 gauze had good dimensional stability and uniformity of opening, and were high-quality high-modulus and high-mesh gauze.

〔The invention's effect〕

According to the method for producing a monofilament gauze made of polyethylene terephthalate according to the present invention, it has extremely excellent dimensional stability and uniformity of opening, and a high fibrous scum that is not woven by shaving or the like and has no weaving defect. High quality and high mesh gauze, especially,
It is possible to stably manufacture gauze that satisfies the characteristics required for high-precision screen printing of electronic circuits and the like.

Claims (1)

[Claims] 1. A polyethylene terephthalate composition, 3.
Weaving monofilaments with a modulus of 5 to 7.0 g / d and a density of 1.3580 to 1.375 g / cm ³ for at least 200
It is characterized in that a gauze having a density equal to or higher than that of a mesh is prepared, and thereafter, this gauze is stretched at least in a warp yarn direction at a draw ratio of 2 to 15% and heat set at a temperature of 160 ° C to 230 ° C. A method for producing a high mesh, high modulus polyester screen gauze.