JPH0295895A - Production of high-mesh high-modulus polyester gauze - Google Patents

Abstract

PURPOSE:To obtain a high-modulus gauze having excellent dimensional stability to external forces by weaving high-strength monofilaments having a specified modulus and a specified density to form a high-density gauze, then stretching the gauze in the direction of warp, and heat-setting the stretched gauze. CONSTITUTION:A monofilament to be used must have a modulus of 3.5-7.0g/d, and it is important for the monofilament to have a density of 1.3580-1.3750g/cm<3>. It is necessary that polyethylene terephthalate monofilaments having a modulus and a density in the above ranges are woven into a high-mesh gauze of at least 200 mesh, and the gauze is stretched in the warp direction in a draw ratio of 2 to 15%. The gauze thus stretched is heat set at a temperature of 160 to 230 deg.C. As a result, a high-mesh high-modulus gauze with no weave defects and with high quality can be stably produced which has extremely excellent dimensional stability and uniformity of openings, and is free of possibility that fibrous scum may be woven in due to shaving or the like.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for producing screen gauze made of high mesh, high modulus polyester monofilament suitable for screen printing of electronic circuits, etc. By weaving gauze from a specific high-modulus polyester monofilament suitable for post-processing, and then stretching and heat-setting the gauze, we can create high-grade, high-mesh, high-modulus fabrics with excellent dimensional stability and opening uniformity. This invention relates to a method for manufacturing screen gauze.

[Conventional technology]

In recent years, screen printing has become a printing method that is simpler and more productive than other printing technologies, not only in the field of printing various electronic circuits, but also in other printing fields.
Its spread is remarkable.

There are many fibers that make up the conventional screen gauze used in screen printing, including 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 they are inexpensive and have excellent properties such as dimensional stability for screen gauze.

However, in order to meet the strong demand for further improvement in printing accuracy in the recent electronic circuit printing field,
It is necessary to reduce the denier of the monofilant to provide a high-strength, high-modulus screen gauze that has a large opening area, good ink permeability, little dimensional change in response to external forces, and does not easily tear the gauze. be. For example, gauze made of monofilament with a strength of 5 g/d and a weave density of 305 mesh usually has a breaking strength of 28 to 35 Kg and a modulus of 16 to 18 Kg.
However, with this level of strength, the gauze tends to warp due to the high tension when it is stretched. Furthermore, a higher modulus is required to enable high-precision printing.

-S, in order to obtain a polyester monofilament with high strength, high modulus, and fine denier, there is a method of drawing a melt-spun undrawn monofilament at a high drawing ratio. However, although the monofilament obtained by this method has high strength, high modulus, and fine denier, it inevitably has a greatly reduced elongation, is rigid, and hard, and the surface of the monofilament is damaged by the reed during weaving. It is scraped, fiber waste is generated, and a fibrous scum consisting mainly of this fiber waste is generated rapidly. Due to the generation of this fibrous scum, weaving becomes impossible, or even if weaving is possible, only gauze with extremely low quality scum woven into it can be obtained.

Therefore, in order to reduce the occurrence of such scum, such as white powder scum, a non-grade, non-reactive polymer or silica gel is contained in polyester to create a high-strength, A high Young's modulus monofilament has been proposed (Japanese Unexamined Patent Application Publication No. 58-23936), but this method contains unsatisfactory and non-reactive polymers or silica gel in the monofilament. The strength and elongation were reduced, and the strength, elastic recovery power, and durability of the obtained screen gauze were reduced, and the performance as a screen gauze could not be fully satisfied.

In addition, it is treated with reactive silicone resin, and the surface is coated with 0.1~
A monofilament coated with 0.7% by weight of the resin has been proposed (Japanese Unexamined Patent Publication No. 169540/1983), but
In this case, it is extremely difficult to uniformly apply a small amount of the relatively highly viscous treatment agent to the surface of the monofilament, and moreover, the adhesiveness of the silicone resin cross-linked on the surface of the polyester filament is insufficient. During warping or weaving, some parts of the paper peel off and fall off and are woven into the screen gauze, degrading the quality of the gauze, or during the finishing process of the screen gauze, it peels off and falls off, reducing printing accuracy.

A filament in which particulate matter is attached to the surface of the filament or a filament in which particulate matter is coated with a sticky water-soluble resin has been proposed (Japanese Patent Laid-Open No. 1164412/1983), but the filament obtained by such a method is Although the coefficient of dynamic friction decreases and the smoothness improves, the fine particles do not adhere uniformly to the surface of the filament and the adhesive strength is insufficient, so the fine particles are removed due to strong abrasion by the reed during weaving of high-density screen gauze. There was a problem in that the particles fell off and were woven into the screen gauze, degrading the quality of the screen gauze. Furthermore, when using a water-soluble resin, it is difficult to uniformly remove particulate matter in the screen gauze scouring process, and there is also the problem that opening accuracy is lacking in high mesh screen gauze.

Furthermore, in JP-A No. 61-282424, the intrinsic viscosity is 0.7 to 1.2, and the content of titanium oxide is 0.1 weight 2.
Below, seven filaments for screen gauze have been proposed, which are obtained from polyester with a carboxylic acid residue content of 25 eq/10' or less, have high toughness, high modulus, and have improved fibrillarity on the fiber surface. 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, which not only makes it impossible to solve the problem of the generation of fibrous scum, but also makes it difficult to obtain The gauze also has the disadvantage that the scraps generated during weaving are woven into the gauze, impairing the quality of the gauze.

[Problem to be solved by the invention]

Therefore, the present inventors have combined not only the characteristics of the polyethylene terephthalate monofilament used as screen gauze but also the post-processing conditions of the gauze made of the monofilant to achieve high dimensional stability, uniform opening, and high quality screen gauze. A method for producing high-quality screen gauze suitable for mesh high modulus high-precision screen printing, in particular, the physical properties of the monofilament constituting the gauze, the microstructure centered on the polymer matrix or crystal structure, and the post-processing conditions of the gauze. The present invention was discovered by intensively studying the relationship between the two.

That is, an object of the present invention is to provide an opening method that enables high-precision printing, which is strongly desired in the electronic circuit printing field, and which has not been possible with the above-mentioned conventional screen gauze manufacturing method using high-strength polyester monofilament. To provide a method for manufacturing a high-strength, high-modulus screen gauze having a large area and excellent ink permeability and dimensional stability against external forces.

[Means to solve the problem]

The object of the present invention is to weave a high-strength monofilament made of polyethylene terephthalate having a modulus of 3.5 to 7.0 g/d and a density of 1.3580 to 1.3750 g/cm3 to obtain a high density of at least 200 meshes. This can be achieved by creating a gauze, then stretching the gauze at least in the warp direction at a stretching rate of 2 to 15[chi], and heat setting it at a temperature of 160 to 230C.

The monofilament used in the present invention has a modulus of 3.5 to 7.0, which is measured according to the measurement method described below.
It is necessary to be within the range of g/d. This monofilament with a low modulus produces less fibrous scum, so it is advantageous in terms of improving weavability. However, if the modulus is less than 3.5 g/d, the modulus of the obtained gauze will be too low, and the stretching rate in the post-processing will have to be increased, which may cause the gauze to tear or the opening to be damaged during stretching. uniformity deteriorates,
This is not preferable because it results in a gauze with an uneven mesh. On the other hand,
If the modulus exceeds 7.0 g/d, fibrous scum will be generated during weaving and will be woven into the gauze, which is not preferable because it will degrade the quality of the gauze.

Furthermore, the monofilament used in the present invention has a density of 1.3580 = 1.3580 as measured according to the measurement method described below.
It is important that the density is within the range of 1.3750 g/cm3, and this density is preferably between 1.3580 and 1.370.
It is preferably within the range of 0 g/cm'. The lower the density, the smaller the progress of crystallization, and the resulting gauze is more flexible, and during post-processing, it is possible to stretch at a high stretching rate with a relatively low stretching tension, and the opening (i.e., mesh) is uniform. A high modulus processed gauze can be obtained. However, the density is 1.3580 g/
If it is less than cm3, it is not preferable because the shrinkage during heat setting of the yarn will be too large, causing troubles such as breakage of the gauze during processing.

In addition, if the density is thicker than 1.3750 g/cm'', the stretching tension of the gauze will be high and the gauze will curl, making it difficult to stretch the gauze uniformly at a high stretching rate. This is undesirable because it causes uneven stretching and the opening of the processed gauze becomes uneven.

Therefore, the monofilament used in the production of the gauze of the present invention, for example, has a breaking strength of 5.1 g/d or more to create gauze, and by stretching and heat setting the gauze, uniform opening can be achieved. When trying to obtain high mesh/high modulus processed gauze,
It is important that the density is within the range of 1.3580 to 1.3750 g/cm''.

Next, in the present invention, a monofilament made of polyethylene terephthalate that satisfies the above-mentioned modulus and density is woven into a high mesh gauze of 200 meshes or more, and then the gauze is woven at a stretching rate of 2 to 15χ in at least the longitudinal direction. It is necessary to stretch it.

If the weave density of the gauze before post-processing is not at least 200 mesh, it will not be possible to obtain a high-mesh processed gauze. The higher the weaving density, the easier it is to obtain high-mesh gauze, but in consideration of ease of weaving, it is preferably 680 mesh or less, and more preferably in the range of 250 to 600 mesh. .

Furthermore, when the stretching ratio of the gauze is less than 2'A, it is impossible to obtain the desired high-mesh processed gauze;
On the other hand, if it exceeds 15χ, it is easy to cause curling during stretching, and the density of the gauze before stretching must be increased, and in the case of gauze with a high weaving density, fibrous scum will occur during weaving. , weaving becomes difficult.

Therefore, in the method for manufacturing screen gauze of the present invention, it is important to create a specific gauze from the specific monofilant specified in the present invention and process it under the above specific conditions, and these requirements and post-processing Only when these conditions are simultaneously satisfied can the fabricated gauze that is the object of the present invention be produced.

Here, as for the method of stretching the gauze, in order to facilitate uniform stretching and obtain gauze with a uniform opening and high modulus, the gauze is pre-heated at a temperature of Tg -30°C to 'rg +so°C (Tg is It is desirable to preheat within the temperature range (the glass transition point of polyester).

The thus preheated gauze is stretched at least in the warp direction (the direction in which the warp threads are pulled) at a stretching rate of 2 to 15χ, but the stretching method is not particularly limited, and for example, a feeding roller or a There is a general method of continuously stretching the gauze using a device equipped with a stretching roller, or a method of fixing both sides of the gauze and stretching it in the bamboo direction of the gauze, and then stretching it in the horizontal direction.

Here, the stretching rate means, for example, when stretching in the vertical direction, the number of weft threads per inch of gauze before stretching is 1°/inch, and the number of weft threads per inch of gauze after stretching is P. In books/inch, it means the value shown by the formula % formula %.

In the present invention, in order to obtain more uniform and high-mesh processed gauze, the cough stretching rate is 3 to 10χ, preferably 4
It is preferable to set it in the range of ~8χ.

The thus stretched gauze is heat set at a temperature of 160°C to 230°C. As this heat setting means, there is a method in which the material is set between a supply roller and a stretching roller, but a method in which the material is first stretched and then heat set may also be adopted.

If this heat setting temperature is lower than 160°C, the heat setting of the gauze will be insufficient, the change over time after gauze will be large, the dimensional stability will deteriorate, and the printing resistance will be poor, which is undesirable. . The higher the heat setting temperature is, the smaller the change over time of the gauze becomes, and the printing resistance and strength are improved. However, when it exceeds 230°C, it approaches the melting point of polyethylene terephthalate, and the monofilaments that make up the gauze become weaker. This is not preferable because it tends to cut and cause the gauze to curl.

Considering the aging 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.

Furthermore, the monofilament used in the present invention preferably has a crystal size in the (100) plane of 15 to 32 angstroms, as determined by wide-angle X-ray diffraction, which will be described later.
A range of 0 to 30 angstroms is desirable. Such crystal size is strongly related to the dimensional stability of the textured gauze obtained from the monofilament.

In other words, the smaller the crystal size of the monofilament, the more microcrystals that serve as nuclei are present, so crystallization progresses centering around the microcrystals during heat setting of the gauze.
The dimensional stability and strength of the obtained processed gauze are improved. In particular, when the crystal size is 15 angstroms or more, it is advantageous because melting of the microcrystals is reduced during preheating before stretching the gauze.

However, when stretching and heat setting a gauze made of monofilaments having a crystal size in such a range, for example, even if the heat setting temperature is 165°C, the size corresponding to a heat setting temperature of 175°C to 185°C is required. It can be made into a processed gauze having stability and strength.

Furthermore, the monofilament of the present invention has a breaking strength of 4
．． It is desirable that it be within the range of 8 g/d to 8.0 g/d. If the breaking strength of this monofilament is 4.8 g/d or more, it is possible to prevent the gauze from curling even when gauze having an extremely small wire diameter is stretched. but,
If the breaking strength becomes too large and exceeds 8.0 g/d, the surface of the monofilament will be easily scraped by a reed during weaving, which is not preferable.

Moreover, the elongation at break of the monofilament is 3 at 15% or more.
It is preferable that it be within a range not exceeding 5χ.

The lower the elongation at break, the higher the modulus of the monofilament, but this is not preferable because the surface of the monofilament is more likely to be scraped by the reed during weaving. When the elongation at break is 15% or more, the monofilament is extremely less likely to be scraped by the reed during weaving, making it easier to obtain high-quality processed gauze (
Become.

On the other hand, if the elongation at break is increased, it becomes necessary to stretch the gauze at a higher stretching rate, making it difficult to obtain a uniform high-mesh processed gauze.

The monofilament of the present invention preferably has a fineness of 5 to 30 deniers, preferably 6 to 20 deniers. The reason for this is that the finer the fineness, the better the opening area of the gauze can be obtained, but it is more likely that curls will occur when the gauze is stretched, and if the fineness is too large, the opening of the high mesh gauze will be reduced. This is because it becomes processed gauze, which is undesirable.

The polyester in the present invention is a polyester mainly composed of polyethylene terephthalate. More specifically, it is a polyester whose main repeating unit is ethylene terephthalate, but terephthalic acid (TP
Dicarboxylic acids such as phthalic acid, adipic acid, sebacic acid, oxalic acid, propylene glycol, butanediol, other than component A) and ethylene glycol <EG) component,
It may also be a monofilament made of polyester copolymerized and/or mixed with a small amount (usually 20 moles or less) of a diol such as polyethylene glycol or polytetramethylene glycol, or a third component such as pentasodium sulfoisofucric acid. .

Furthermore, for the purpose of preventing halation or improving weavability, it may be a polymer containing fine particles such as titanium dioxide or silicon dioxide, or a polymer containing particles generated in the polymer during the polymer manufacturing process, that is, a polymer containing internal particles. . In particular, the monofilament used in the present invention preferably contains titanium dioxide particles, and the amount added is preferably in the range of 0.2 to 0.7χ. The titanium dioxide particles can be very uniformly dispersed in the polyester by applying known dispersion techniques. As a result, it is possible to form uniform fine concavities on the fiber surface and reduce the friction coefficient of the fibers, so when weaving monofilaments having the modulus specified in the present invention, it is possible to effectively prevent the occurrence of abrasion in the reed. can be prevented. In particular, when the amount of titanium dioxide particles added is 0.2% or more, scraping in the flow will not occur. In addition, by setting the amount of the titanium dioxide particles to be 0.7z or less, the titanium dioxide particles can be uniformly dispersed in the polymer, and the generation of coarse particles can be prevented, so that the surface of the monofilament is is uniform and forms minute depressions,
Scraping caused by the reed will no longer occur.

Furthermore, in order to prevent halation caused by exposure to ultraviolet light in the screen plate-making process, a polymer containing an ultraviolet absorber can be used as the polyester for producing the monofilament.

The appropriate degree of polymerization of the polyester is such that the intrinsic viscosity measured in an 0-chlorophenol solution at 35°C is 0.5 or more, preferably 0.7 to 1.4.

Furthermore, a polymer containing an ultraviolet absorber may be used to prevent halation during exposure to ultraviolet light in the screen plate-making process.

The monofilament of the present invention is usually produced by extruding a polymer using a pressure melt type or extruder type melt spinning machine, applying an oil agent, creating an undrawn monofilament or an undrawn monofilament with a certain degree of orientation, and then drawing with a heating device. It can be manufactured by stretching with a machine.

The important thing here is that the density of the monofilament depends on the degree of polymerization of the polyethylene terephthalate used, the type of copolymer components such as isophthalic acid and sebacic acid, and their copolymerization ratio.
Furthermore, it depends on the spinning speed, the heat setting temperature and time during stretching, so it cannot be said unconditionally, but the type of polymer used, the spinning・Stretching conditions should be selected and determined appropriately. For example, the stretching temperature of an undrawn monofilament is 90°C to 120°C, and the heat setting temperature is relatively low, and the appropriate temperature is 90°C to 160°C for 0.1 to 0.3 seconds. The crystal size cannot be determined unconditionally because it 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 it satisfies the requirements stipulated in the present invention. Conditions are appropriately selected and determined so as to obtain a monofilament with the following properties. 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 during heat setting during stretching is set to be equal to or lower than the tension required for stretching. In addition, after spinning, -dan,
A direct stretching method in which the film is stretched continuously without winding can also be adopted. Alternatively, a method of spinning the fiber into a multifilament and splitting the fiber to produce a monofilament 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.

Moji 1 lath, degree of rupture, elongation at break: The tensile force when the sample breaks was measured using an Instron universal tensile tester in an atmosphere of a temperature of 20°C and a relative humidity of 65χ at a sample length of 20 cm and a speed of 20 cm/min. It is expressed as a value divided by the denier before tension.

In addition, the elongation at break of the sample was defined as the elongation at break.

The value obtained by dividing the tension (g) at an elongation of 10χ by the denier before tension was defined as the modulus axis/d).

1 degree: By density gradient tube method using density gradient consisting of carbon tetrachloride/n-hebutane, the apparent density of monofilament is d
The density d was calculated according to the following formula.

d = (d'(1-A/100)) / (1-(A
xd')/100 B) In the above formula, A is the amount (wt%) of additives other than polymers (fine particles, etc.) contained in polyester, and B is the amount of additives other than polymers contained in polyester. (fine particles, etc.) density (g/cm3).

A self-centered prisoner: Surface index (100) obtained by transmission method using a 4036 A2 type wide-angle x'fFA diffractometer manufactured by Rigaku Corporation.
It was determined from the value of the peak half-width according to the following Scherrer equation.

L(100) = λ/βa cos θ However, β.

′=βE′=β,′β,−apparent half width,βr=1.05×10−”rad,K=1.0
, λ - wavelength of X-ray, θ = Bragg angle, L (100)
==The average size in the direction perpendicular to the (100) plane of the microcrystal, and this was expressed as the crystal size.

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

Modulus of Ha, strength: JIS-L using test machine AC-B manufactured by Shimadzu Corporation.
-1068 (1979), using the Labelt strip method, sample width 50 mm, grip interval 200 mm.
A strong Kerr elongation curve was obtained at a tensile speed of 100 mm/min. The strength when the elongation was 10χ was taken as the modulus of the gauze, and the strength at break was taken as the breaking strength of the gauze.

Suhiro Song: Using Shimazu Autograph 5D-100, measure the sample width 5
0n+m: Grasp interval 200Iam, pulling speed 10m
Pull the tester to a tension of 20 kg at m/min, stop the tester, operate only the recording chart, and test 2 times in that state.
Leave for 0 minutes. Tension T2゜(Kg) after 20 minutes
is read and the change fiY(χ) is determined from the following equation.

Y= ((20-TZO) /20) xlooo The smaller this change IY, the less the gauze tension deteriorates over time and the dimensional change during printing, indicating that the dimensional stability and printing resistance are better.

If this change IY is 81.0% or less, the dimensional stability is good, if the change Y is 81.1χ to 83.0χ, the dimensional stability is somewhat good, and if the change Y is 83.1% or more, the dimensional stability is poor. did.

Evenness of opening - Observe the processed gauze using a transmission microscope, and calculate the opening distance (distance between adjacent warp threads and warp threads or between weft threads that make up the gauze) for n = 100 warp threads. and between the warp threads and between the weft threads and the weft threads, and the standard deviation was determined for each. The smaller the standard deviation obtained, the more uniform the opening of the gauze was, and was expressed as follows.

○...The accuracy of the opening is good. ×... The accuracy of the opening is poor.

In addition, the quality of the gauze was evaluated by observing the fibrous scum woven into the gauze and using the following criteria.

O: The number of scum per 1 m of gauze is 0.2 or less, and there is almost no fibrous scum. ×: The number of scum per 1 m of gauze is more than 0.2, and fibrous scum is observed.

〔Example〕

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

In the example, a polyethylene terephthalate ζ drawn yarn containing 0.35% by weight of titanium oxide was melt-spun with adjusting the spinning so that the fineness was 11.5 denyl, a finishing oil was applied, and the yarn was wound up. The temperature of the yarn at 1m below the nozzle is 130℃~
The temperature was adjusted to 150°C. The obtained undrawn monofilament was drawn at a drawing ratio of 3.7 times using a drawing machine equipped with a heating device.

The obtained monofilament drawn yarn had a strength of 6 g/d, an elongation of 32χ, a modulus of 3.9 g/d, and a density of 1.366 g/d.
cm3, and the crystal size was 23 angstroms.

This monofilament was woven using a Sluzer loom with the weave density adjusted so that the weave density was 305 mesh after the gauze was heat set. There was little occurrence of fibrous scum on the reed during weaving, and no fibrous scum was woven into the gauze. Further, the obtained gauze was preheated at 92°C, and while being stretched in the warp direction at a stretching rate of 6.7χ,
'C set the temperature to 7.

The modulus of the gauze was compared before and after stretching.

The modulus of the gauze in the warp direction after stretching was 28 kg, compared to 6 kg before stretching, and a high mesh, high modulus processed gauze was obtained which was well balanced with the weft direction.

The processed gauze was a high-strength gauze with a breaking strength of 42 kg, and was extremely good in terms of dimensional stability, opening uniformity, and gauze quality.

In other words, this processed gauze was a high-quality, high-modulus, high-mesh gauze made of fine denier monofilament without woven fibrous scum.

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

These drawn monofilaments were woven using a Sluzer loom, with the weave density adjusted to a weave density of 320 mesh after heat setting the gauze.

Furthermore, after stretching the obtained processed gauze in the warp direction and then in the weft direction so that the modulus of the processed gauze was 24 kg, No. 4 in Table 1 was stretched at 165°C.
Other items were heat set at 180°C.

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

(The following is a blank space) Table 1 In Table 1, No. 1 has a low modulus of monofilament, so in order to obtain a high modulus gauze, the stretching rate had to be increased, and considerable curling of the gauze occurred. .

Furthermore, the obtained processed gauze had poor opening uniformity and non-uniform mesh. In No. 5, the monofilament had a high modulus, fibrous scum was woven into the gauze, and the quality of the gauze was poor. In No. 6, the density of the monofilament was high, so the stretching tension of the gauze was high, making it difficult to stretch it uniformly, causing uneven stretching, and resulting in a processed gauze with non-uniform openings.

In No. 7, because the density of the monofilament was low, the shrinkage during heat setting was too large, causing cracks in the gauze.

No, 2. Nos. 3 and 4 were gauze that satisfied the specifications of the present invention, and were high mesh and high modulus gauze with good dimensional stability, opening uniformity, gauze quality, and gauze quality. The crystal sizes (100) of No. 3 and No. 4 were 38 angstroms and 24 angstroms, respectively. 1 if No, 4
Despite being heat set at a low temperature of 65°C, the
A textured gauze was obtained with similar performance to that heat-set at °C.

Example 3 Weaving was carried out using the monofilament of Example 1 and adjusting the weave density so that the weave density of the gauze after heat setting was 320 mesos. The resulting gauze had no fibrous scum woven into it. Subsequently, the gauze was post-processed by varying the stretching ratio in both the vertical and horizontal directions and the temperature during heat setting. The processed gauze thus obtained was evaluated and observed for modulus in both vertical and horizontal directions, dimensional stability, opening uniformity, and gauze tearing, and the results shown in Table 2 were obtained.

(Hereafter, margin) It is possible to stably produce gauze that satisfies the desired characteristics.

Claims (1)

[Claims] Made of polyethylene terephthalate, 3.5 to 7.0
modulus of g/d and 1.3580 to 1.3750
A monofilament having a density of g/cm^3 is woven to create a gauze having a density of at least 200 mesh, and then this gauze is woven at least 2 times in the warp direction.
Stretched at a stretching rate of ~15% and 160°C ~2
A method for producing a high mesh/high modulus polyester screen gauze characterized by heat setting at a temperature of 30°C.