JPH11107147A - Chemical-resistant conjugate fabric and formed product obtained by using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject fabric, in which an undrawn polyphenylene sulfide fiber nonwoven fabric and a fabric comprising a chemical-resistant fiber are laminated and both are entangled in the boundary part and contact points among fibers are bonded and fixed, suitable for filter-related uses in which chemical resistance is required. SOLUTION: This conjugate fabric is obtained by laminating a polyphenylene sulfide fiber nonwoven fabric which has $10 μm fiber diameter and is substantially not drawn and a fabric such as a nonwoven fiber aggregate, e.g. filament nonwoven fabric, short fiber nonwoven fabric or web aggregate, knitted fabric or woven fabric comprising a chemical-resistant fiber such as polyphenylene sulfide fiber having >=15 μm fiber diameter, and entangling the both, preferably by stream in at least their laminated boundary part and bonding and fixing the contact points among fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite fabric excellent in chemical resistance and a molded article using the same, and its use is in general industrial fields, particularly where chemical resistance is required. It can be suitably used for filter-related applications.

[0002]

2. Description of the Related Art Conventionally, fluorine-based fibers, aramid fibers, polyimide fibers, polyarylene fibers and the like are generally known as fibers having excellent chemical resistance and heat resistance. Among them, aramid fiber is hydrolyzed under high temperature and heat,
The strength is greatly deteriorated by alkalis and acids. Further, the tetrafluoroethylene fiber has good chemical resistance, but has a low strength and has a problem in workability. In contrast,
Polyphenylene sulfide fibers are excellent in alkali resistance, acid resistance and heat resistance, and are often used in fields requiring very high chemical resistance such as liquid filters for waste solvents and in fields where heat resistance is required.

[0003] Many proposals have been made on sheet-like materials using the PPS fiber and methods for producing the same.
For example, Japanese Patent Publication No. 52-30609 discloses PPS fibers, and discloses that a woven or knitted fabric is obtained from fibers obtained by such a technique.

However, when used for applications such as filters, woven or knitted fabrics necessarily have large voids in the vicinity of the fiber entanglement point, and are liable to slip due to mechanical entanglement. On the other hand, in the field of non-woven fabrics, there is a method in which fibers are entangled by subjecting a PPS short fiber web to a high-pressure water flow method or a needle punching process. Things were hard to get. Japanese Unexamined Patent Publication (Kokai) No. 61-289162 proposes a method for producing a nonwoven fabric by subjecting a mixed cotton web of drawn polyphenylene sulfide fiber and undrawn polyphenylene sulfide fiber to heat treatment under pressure. However, when it is used for a filter or the like for a non-woven fabric made of fibers having a fiber diameter of 10 μm or more, there is a problem that even fine particles having a small particle diameter cannot be filtered.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to use, for example, a filter which is required to have a high level of chemical resistance, and is also required to have shape retention and heat resistance. It is an object of the present invention to provide a fabric suitable for the field of collecting fine particles having a small particle diameter, and a molded article using the same.

[0006]

As a result of intensive studies to solve the above-mentioned problems, the present invention has revealed that a chemically resistant fiber cloth having a fiber diameter of 15 μm or more and a substantially stretched fiber diameter of 10 μm or less have been obtained. By laminating non-woven polyphenylene sulfide fiber non-woven fabrics, performing hydroentanglement with relatively low water pressure, and then performing heat treatment, separation between the laminations can be suppressed, and a chemically resistant composite fabric excellent in shape retention can be obtained. It was also found that the intended purpose could be achieved when used for industrial materials such as filters, and the present invention was completed.

The present invention has solved the above-mentioned problems by the following constitution. (1) A non-stretched polyphenylene sulfide fiber non-woven fabric having a fiber diameter of 10 μm or less and a chemically resistant fiber cloth having a fiber diameter of 15 μm or more are laminated, and both are entangled at least at a lamination boundary portion. A chemical-resistant composite fabric, characterized in that contact points between the two are adhered and fixed. (2) The chemical-resistant composite fabric according to item (1), wherein the nonwoven fabric of polyphenylene sulfide fiber and the chemical-resistant fiber fabric are entangled by a water flow. (3) The chemical-resistant composite fabric according to (1) or (2), wherein the chemical-resistant fiber fabric is a polyphenylene sulfide fiber. (4) The non-woven fiber aggregate, the knitted fabric,
(1) to (3) which are at least one selected from woven fabrics
Item 7. The chemical-resistant composite fabric according to any one of the above items. (5) The chemical-resistant composite fabric according to item (4), wherein the nonwoven fiber aggregate is at least one selected from a long-fiber nonwoven fabric, a short-fiber nonwoven fabric, and a web aggregate. (6) A molded article using the composite fabric according to any one of (1) to (5).

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A chemically resistant fiber cloth having a fiber diameter of 15 μm or more suitably used in the present invention may be any fiber as long as it is obtained from a resin having chemical resistance and heat resistance. Is an undrawn polyphenylene sulfide (P
PPS fibers and polyetheretherketone (PEEK) fibers are preferred in view of the hydroentanglement after lamination with the fiber nonwoven fabric and the adhesive strength during heat treatment. In particular, PPS fibers are the same as the components of the unstretched PPS fiber nonwoven fabric to be laminated, and have high compatibility and are most preferable. The fabric referred to in the present invention may be any fabric as long as it is in the form of a cloth, such as a woven fabric, a knitted fabric, a nonwoven fabric, or a non-woven fiber aggregate. Further, fibers mixed by a method such as cotton blending, blending, blending, twisting, knitting and weaving can be formed into a cloth form by the above method. In addition, the nonwoven fiber aggregate is, for example, a card-like method, an airlaid method, or a web-like material made uniform by a method such as papermaking, or a woven fabric,
It refers to a layered knit. A woven fabric is a cloth woven using warp and weft, and a knitted fabric is a cloth made by using a series of yarns and binding loops vertically or horizontally to form a flat shape.

This PPS fiber has a repeating unit
It is a fiber comprising a polymer containing phenylene sulfide units such as p-phenylene sulfide units and m-phenylene sulfide units. The PPS fiber may be a homopolymer or a copolymer of p-phenylene sulfide unit and m-phenylene sulfide unit, and may be a copolymer or a mixture with another aromatic sulfide without departing from the gist of the present invention. It may be. Among the PPS fibers, a substantially linear polymer containing 70% by weight or more, preferably 90% by weight or more of a p-phenylene sulfide unit as a repeating unit is preferable.

[0010] PPS used for such PPS fiber
As a method for producing a resin, a method of industrially reacting p-dihalobenzene with sodium sulfide to remove a halogen element as sodium halide to produce a PPS resin is used. A polyhalo aromatic compound having a substituent of more than two halogen atoms with respect to p-dihalobenzene in an amount of 0.1 to 5
Branched polymers with mol% added are also included in the preferred polymers.

The single fiber fineness of the chemical resistant fiber fabric suitably used in the present invention is not particularly limited as long as it is 15 μm or more. For example, when it is used for a filter, it is preferably 15 to 50 μm. In addition, when using a card and air raid, the fiber length should be considered in consideration of workability.
3-90 mm is preferred. Further, the cross-sectional shape of the PPS fiber can be circular or irregular. In the case of an irregular cross section, for example, a flat shape, a square shape such as a triangular to octagonal shape, T
The shape may be any shape such as a letter shape, a multi-lobe shape, a hollow cross-section shape, and is not particularly limited. In addition, commonly used additives such as pigments, carbon, heat stabilizers, ultraviolet absorbers, lubricants and the like can be used as needed as long as the effects of the present invention are not impaired.

In the method for producing a non-woven fabric of chemical resistance fiber, preferably a non-woven fabric of PPS fiber, which is suitably used in the present invention, first, PPS pellets are melt-spun, and a usual melt-spinning step can be employed. . That is, a PPS resin melted at about 300 to 350 ° C. by an extruder is extruded from a nozzle, cooled in a medium such as air, water, glycerin or the like at a temperature lower than the glass transition temperature, and wound around a roll.
The roll can be wound usually at a speed of 100 to 1500 m / min.

The undrawn yarn thus obtained by melt spinning is then drawn at a draw ratio of about 2 to 5 times. The stretching temperature is usually the glass transition temperature of the PPS resin, ie, 9%.
It is possible from around 0 ° C. By drawing, the PPS fiber is given strength, chemical resistance, heat resistance, and the like. The method of stretching the PPS fiber is not particularly limited, but is usually stretched at a ratio equal to or higher than the natural stretching between the supply roll and the take-up roll. The stretching may be performed in one-stage stretching, or may be performed in two or more stages.

After stretching, a constant-length heat treatment or a relaxation heat treatment at a temperature equal to or lower than the melting point may be performed, if necessary, to improve dimensional stability and promote crystallization. This heat treatment can be performed by a conventional method, and the conditions are not particularly limited. For example, in a dry heat atmosphere at 200 to 280 ° C., a stretching ratio of 0.8
A method in which heat treatment is performed for 1 to 50 seconds under conditions of up to 1.2 times. The obtained drawn PPS fiber is subjected to mechanical crimping and cut into a predetermined length.

The basis weight of the web is not particularly limited.
It is not, but 10-200 g / m ^TwoThings are preferred
No. 10g / m^TwoIf less, the basis weight is too low and uniform
Not only is it difficult to produce
Its value as a cloth is also poor. On the other hand, the basis weight is 200g
/ M^TwoChemical resistance due to water entanglement at relatively low water pressure
Entanglement of non-stretched PPS fiber non-woven fabric laminate
Becomes difficult. As a result, a strong composite fabric can be obtained.
It is difficult and may cause chemical resistant fibers to fall off the nonwoven fabric.
You. For this reason, chemical-resistant fabrics with a large basis weight are
Pre-entanglement of the fiber in advance by the squeeze method or the high-pressure water flow method
The fibers are ideally three-dimensionally entangled, so the basis weight is thick
Even after this, the fiber is not detached, and the strength can be maintained.
Needle punch method and high-pressure water flow method use conventional methods
be able to. For example, the needle punch method is 30 to 15
0 points / cm^TwoCan be needle punched
preferable.

Next, the non-stretched non-stretched PPS fiber nonwoven fabric having a fiber diameter of 10 μm or less according to the present invention (unstretched PPS fiber nonwoven fabric)
PS fiber non-woven fabric) is a non-woven fabric that has a lower melting point or softening temperature than the above-mentioned chemical resistant fiber fabric, and can be melt-bonded when laminated with a chemical resistant fiber fabric and heated or heated under pressure. is there. As the undrawn PPS fiber nonwoven fabric, an undrawn yarn obtained by a usual spinning step or a nonwoven fabric obtained by a melt blow method is preferable.

The unstretched PPS fiber obtained in the ordinary spinning step is defined as PPS pellets melted at about 300 to 350 ° C. by an ordinary extruder.
The resin is extruded from a nozzle, cooled in a medium such as air, water, or glycerin at a temperature equal to or lower than the glass transition temperature, and wound around a roll. Roll take-up speed is usually 100 to 1500 m
/ Min. In order to prepare a web having a desired basis weight using a carding method, an air laid method, or the like, a mechanical crimp is applied and cut into a predetermined length. In the case of long fibers, the web may be prepared by directly opening the tow. Next, among the unstretched PPS fiber nonwoven fabrics, the melt blown nonwoven fabric which is preferably used is a high-speed heating airflow jetted from both sides while melt-spinning to thin the fibers, and the fibers are collected on a mesh screen to form a nonwoven fabric. It is assumed that.

The unstretched PPS fiber nonwoven fabric contains many unoriented portions and is softened even at a relatively low temperature, so that stretched PPS fibers can be bonded as an adhesive component. That is, by heating under pressure at or above the glass transition point of the unstretched PPS fiber nonwoven fabric, the unoriented portion is softened, and the physical properties of the chemical resistant fiber fabric are not affected, and the nonwoven fabric can be bonded.

The unstretched PPS fiber nonwoven fabric constituting the chemical-resistant composite fabric of the present invention, in particular, PP by melt blow method
The average fiber diameter of the S-fiber nonwoven fabric is 10 μm or less, that is, 1
There is no particular problem if it is 10 to 10 μm. The fiber diameter of one of the chemical resistant fiber fabrics constituting the chemical resistant composite nonwoven fabric of the present invention is preferably equal to or less than the fiber diameter. If the average fiber diameter is larger than that of the chemical resistant fiber cloth, the fiber bonding intersections are small, and it is difficult to obtain sufficient strength. In particular, when the average fiber diameter of the unstretched PPS fiber is 10 μm or less, when the composite fiber is laminated with the chemical resistant fiber fabric, the hydroentanglement is easy in the vicinity of the boundary between the two,
In addition, not only the fine fiber having an average fiber diameter of 10 μm or less, but also the unstretched state has a large pliable soft action, which penetrates deeply into the fiber gap of the chemical resistant fabric to be laminated and is delicately entangled. As a result, the confounding condition is extremely good. This is also important in forming an ideal base for the heat treatment performed after the entanglement treatment, and the heat treatment makes the entanglement of the two more firm and results in a chemically resistant composite fabric that is extremely difficult to peel off. When the unstretched PPS fiber has a fiber diameter of 10 μm or less, when the composite fabric of the present invention is used as a filter, the unstretched PPS fiber nonwoven fabric formed of ultrafine fibers of 10 μm or less has a microporous structure. In this case, in a chemically resistant fiber cloth having a fiber diameter of 15 μm or more, coarse particles are collected and the unstretched P of 10 μm or less is collected.
Since the PS fiber nonwoven fabric captures fine particles, a material having extremely high filtration accuracy in addition to the original chemical resistance can be obtained.
The basis weight of the unstretched PPS nonwoven fabric is 20 to 200 g / m ^2.
A degree is suitably used.

As a preferred embodiment of the present invention, a chemical resistant fiber fabric previously processed by the needle punch method or the high pressure water flow method and an undrawn PPS fiber nonwoven fabric are laminated.
The laminate may be a laminate of one each of a chemical resistant fiber fabric and an unstretched PPS fiber nonwoven fabric, or may be a laminate of a plurality of laminates alternately. The mixed fiber is treated by hydroentanglement at a relatively low pressure, and then heat-treated or heat-treated under pressure to produce the chemical-resistant composite nonwoven fabric of the present invention.

The relatively low water pressure hydroentanglement referred to here is:
For example, the hole diameter is 0.05 to 1.0 mm, especially 0.1 to 0.
This is a method of using a device in which a large number of 4 mm injection holes are arranged, and injecting from the injection holes at a relatively low water pressure of an injection pressure of 5 to 40 kg / cm ² . When the non-stretched PPS fiber non-woven fabric is laminated with the PPS unstretched non-woven fabric and the chemical resistant fiber fabric obtained in the ordinary spinning process, the hydroentanglement may be treated from either side, The pressure can be set relatively high. However, when laminating the nonwoven fabric obtained by the melt blow method and the chemical resistant fiber fabric, the high-density nonwoven fabric obtained by hydroentanglement at a high water pressure or hydroentanglement from the meltblown nonwoven fabric side is greatly damaged. It is preferable to perform the hydroentanglement treatment at a relatively low water pressure from the non-melt blow nonwoven fabric side. The arrangement of the injection holes is arranged in a row in a direction orthogonal to the traveling direction of the web. As the fluid, water or hot water is generally used.
This step may be a continuous step or a separate step. After performing the hydroentanglement treatment, the web may be dried using a drying facility such as a hot air dryer. Thereafter, heat treatment is performed.

A known method can be used for the heat treatment. For example, when processing with a pair of rolls having a smooth surface, it is necessary to perform pressing at a linear pressure of 1 to 50 kg / cm. When the linear pressure is less than 1 kg / cm, sufficient strength cannot be obtained, and when the linear pressure exceeds 50 kg / cm,
The fiber turns into a film. When one of the rolls is replaced with an embossing roll and the fibers present in the embossed pattern portion of the embossing roller are partially thermally bonded to each other, the embossing roll preferably has a pressed area ratio of 5% or more. When the pressed area ratio is less than 5%, the fused area is small and the mechanical strength is reduced, and it is difficult to obtain good dimensional stability. The emboss pattern has a pressed area ratio of 5
% Is not particularly limited as long as it is at least
Any shape such as an elliptical shape, a diamond shape, a triangular shape, a T-shape, and a well shape may be used. The roll may be thermally bonded in a temperature range from the glass transition point to the melting point of the unstretched PPS fiber nonwoven fabric.
The heat bonding temperature is 90-180 ° C. Since such thermal bonding is performed at a low temperature, no special equipment such as a calender roll capable of processing at a high temperature of 250 ° C. or more is required, and processing can be performed with a normal calender roll. This makes it possible to form a nonwoven fabric while maintaining the strength without forming a film of the chemical resistant fabric near the melting point of PPS. In addition, when the heat treatment is performed at a high temperature close to the melting point of the PPS resin, the heat treatment becomes a paper-like material having a low porosity, and it is difficult to obtain a filter or a material suitable for use as a molded body. Further, the heat resistance of the unstretched PPS fiber nonwoven fabric is greatly improved by heat processing, and a chemically resistant composite fabric having heat resistance can be obtained.

By laminating the unstretched PPS fiber nonwoven fabric and the chemical resistant fiber fabric and treating them by hydroentanglement at a relatively low water pressure, peeling between the laminations can be greatly suppressed. In addition, the fibers between the layers are entangled in order to melt-bond the unstretched PPS fiber nonwoven fabric portion by heat treatment. In particular, both are strongly entangled at the lamination boundary. In particular, since the two are firmly entangled at the lamination boundary, a composite fabric having high peel strength can be obtained. As a result, it is possible to obtain a fabric which has chemical resistance and heat resistance, and which can be collected from materials having fine shape retention and fine particle diameter, which is suitable for filter applications.

[0024]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. (Basis weight) is the weight per nonwoven 1 m ² (g). (Shape retention) Tensile strength (kg / 5 cm) at 5% width per 5 cm width in the machine direction of the nonwoven fabric. (Tear strength) The tear strength (g / 5 cm) between the layers of the chemical resistant fiber fabric and the unstretched PPS fiber nonwoven fabric. (Air permeability) JIS-L using a Frazier-type air permeability tester
-1096-6-27-1-A method was followed.

(Chemical resistance) After immersion in a 30% by weight aqueous solution of sulfuric acid at 95 ° C. (solution 1) and a 30% by weight aqueous solution of sodium hydroxide at 95 ° C. (solution 2) for 24 hours,
The strength retention after washing with water and drying was measured. Chemical resistance was evaluated by the following three grades based on the strength retention. ：: 80% or more strength retention. Δ: strength retention 50 to 80
%Less than. ×: strength retention less than 50%.

Example 1 (Chemical resistant fiber cloth) PPS resin (melt flow rate (hereinafter abbreviated as MFR): 50 g / 10 minutes, 310 ° C.
2.16 kg load) was pre-dried at 140 ° C. for 2 hours, and then spun at a spinning temperature of 32 with an extruder having a cylinder diameter of 30 mm.
Spinning was performed at 0 ° C. and a winding speed of 800 m / min. The obtained undrawn yarn is drawn three times at 90 ° C., then drawn in two steps at 160 ° C. and 1.2 times, and finally heat-treated at 220 ° C. in a relaxed state, 3 denier (fiber diameter 18 μm) Thus, a PPS fiber having a cut length of 51 mm was obtained. A web having a basis weight of 47 g / m ² was produced from the obtained staple fiber using a card machine. (Unstretched PPS fiber nonwoven fabric) PPS resin (MFR: 13
(0 g / 10 min, 310 ° C., 2.16 kg load) to produce a melt-blown nonwoven fabric having an average fiber diameter of about 10 μm and a basis weight of 29 g / m ² by a melt blow method. (Preparation of Chemical-Resistant Composite Fabric of the Present Invention) The obtained chemical-resistant fiber fabric and unstretched PPS fiber nonwoven fabric are laminated. This non-woven fabric is placed on a 100-mesh plain woven net such that the chemical resistant fiber fabric faces upward, and the nozzle diameter is 0.1 mm.
Water pressure 30kg / c from nozzle plate with pitch 1mm
The hydroentanglement was performed three times at a relatively low water pressure of m ² . After drying this composite fabric, the processing temperature is 90 ° C., the pressure is 10 kg / cm.
Was performed under the above conditions to obtain a chemically resistant composite fabric having a basis weight of 71 g / m ² .

Example 2 The chemical-resistant fiber fabric obtained in Example 1 was placed on a 100-mesh plain woven net, and a water pressure of 20 kg / cm ^{2 was applied} from a nozzle plate having a nozzle diameter of 0.1 mm and a pitch of 1 mm.
, And three times at a high water pressure of 80 kg / cm ² . After drying, a hydro-entangled chemical-resistant fabric having a basis weight of 47 g / m ² was prepared. The unstretched PPS fiber nonwoven fabric obtained in Example 1 was laminated on this cloth, and a chemically resistant composite cloth of the present invention was obtained by the same steps as in Example 1 below.

Example 3 PPS resin (melt flow rate (hereinafter abbreviated as MFR): 50 g / 10 minutes, 310 ° C., 2.16 kg load)
Was pre-dried for 2 hours at 140 ° C.
0 mm extruder, spinning temperature 320 ° C, winding speed 80
Spinning was performed at 0 m / min. The obtained undrawn yarn was made into short fibers having a cut length of 10 mm and an average fiber diameter of 7 μm, and was made into a paper by a tappy type paper machine to prepare an undrawn PPS fiber nonwoven fabric having a basis weight of 47 g / m ² . The obtained unstretched PPS fiber nonwoven fabric and the chemical resistant fiber fabric produced in Example 1 are laminated. This nonwoven fabric is placed on a 100-mesh plain weave net with the chemical resistant fiber fabric facing upward, and three times from a nozzle plate having a nozzle diameter of 0.1 mm and a pitch of 1 mm at a relatively low water pressure of 30 kg / cm ^2. Water entangled.
After drying the composited fabric, calendering was performed under the conditions of a processing temperature of 105 ° C. and a pressure of 15 kg / cm to obtain a chemically resistant composited fabric having a basis weight of 90 g / m ² .

Example 4 Using the chemical-resistant composite nonwoven fabric of the present invention prepared in Example 2, a vertical molded body having a diameter of 250 mm and a diameter of 150 mm was used.
Was manufactured. The following filtration accuracy and filtration life were measured using this filter. (Filtration accuracy) A filter was attached to the circulation type filtration performance tester, and after adjusting the flow rate of water passing through a 50-liter water tank by a pump to 30 liters / minute, AC, which is a standard powder for basic physical properties, was used as a test powder in the water tank. Coarse test dust (abbreviated as ACTCD; median diameter: 27 to 31 μm) is 60
The solution was continuously added at a rate of mg / min, and after 5 minutes from the start of the addition, the undiluted solution and the filtrate were collected, and the particle size distribution of the particles contained in each solution was measured using a light-blocking type particle detector. Using the results of the particle size distribution measurement, the ratio of the number of particles collected by the filter was calculated as the collection efficiency, and the particle size of 99.9% collected was defined as the filtration accuracy of the filter. (Pressure strength) A filter was attached to the circulating filtration performance tester, and the flow rate of water passing through a 50-liter water tank was adjusted to 30 liters per minute by a pump. After that, a standard powder for basic physical properties was used as a test powder in the water tank. A certain AC course test dust (abbreviated to ACTCD; median diameter: 27 to 31 μm)
Add continuously at 00 mg / min, measure the pressure at the primary and secondary sides of the filter and record the change in pressure loss. The pressure loss at the time when the filter was deformed and perforated occurred was defined as the pressure resistance.

Comparative Example 1 The water-needle-processed chemical-resistant fiber fabric prepared in Example 2 alone did not have fiber-to-fiber adhesion, caused misalignment, had a low strength at 10% elongation, and had insufficient shape retention. .

Comparative Example 2 Using a mixed solvent of phenol and carbon tetrachloride in the same amount, the intrinsic viscosity was measured at a concentration of 0.5 g / dl and a temperature of 25 ° C. and was 0.
A 65 dl / g polyethylene terephthalate is spun and stretched using a melt spinning apparatus, and has a fineness of 3 denier (fiber diameter 1
8 μm) and a fiber having a cut length of 51 mm was obtained. A web having a basis weight of 75 g / m ² was prepared from the obtained staple fiber with a card, placed on a 100-mesh plain weave net, and pre-pressed at a water pressure of 20 kg / cm ² from a nozzle plate having a nozzle diameter of 0.1 mm and a pitch of 1 mm. After processing, 40
Treated three times at a high water pressure of kg / cm ² , then invert the entangled tow web and remove 4
The treatment was performed three times with a water pressure of 0 kg / cm ² . After drying, a nonwoven fabric with a basis weight of 72 g / m ² was produced. However, there was misalignment and the shape retention was not sufficient.

Comparative Example 3 The chemical-resistant fiber fabric and the unstretched PPS fiber non-woven fabric prepared in Example 1 were laminated and calendered at a processing temperature of 90 ° C. and a pressure of 10 kg / cm without hydroentanglement. Processing was performed to obtain a nonwoven fabric.

Comparative Example 4 A nonwoven fabric was obtained by laminating the chemical resistant fiber fabric prepared in Example 1 and an unstretched PPS fiber nonwoven fabric, and performing only hydroentanglement.

Comparative Example 5 PPS resin (melt flow rate (hereinafter abbreviated as MFR): 50 g / 10 minutes, 310 ° C., 2.16 kg load)
Was pre-dried for 2 hours at 140 ° C.
0 mm extruder, spinning temperature 320 ° C, winding speed 80
Spinning was performed at 0 m / min. 90 ° C.
The film is stretched three times at 160 ° C., then stretched at 160 ° C. in two steps, and finally heat-treated at 220 ° C. in a relaxed state.
Denier (fiber diameter 18μm), cut length 51mm PP
An S fiber was obtained. A web having a basis weight of 75 g / m ² was prepared from the obtained staple fiber using a card machine. This was placed on a 100-mesh plain weave net, pretreated at a water pressure of 20 kg / cm ² from a nozzle plate having a nozzle diameter of 0.1 mm and a pitch of 1 mm, and then treated three times at a high water pressure of 80 kg / cm ² . After drying, a hydro-entangled chemical-resistant fabric having a basis weight of 71 g / m ² was prepared. Using this chemical-resistant composite nonwoven fabric, a vertical length: 250 m
m, a cylindrical bag filter having a diameter of 150 mm was produced.

Table 1 shows the basis weight of the nonwoven fabrics obtained in Examples 1 to 3 and Comparative Examples 1 to 4, strength at 10% elongation, air permeability, tear strength, and chemical resistance.

[0036]

[Table 1]

As is clear from Table 1, the chemical-resistant composite fabric of the present invention is entangled between the two layers and is thermally bonded. Therefore, even if stress is applied, misalignment and delamination hardly occur. The form was preserved. Further, it was very excellent in chemical resistance.

Further, as is apparent from Example 4 and Comparative Example 5, the chemical-resistant composite nonwoven fabric of the present invention is composed of a laminate of a chemical-resistant fiber fabric and a non-stretched fine-strength PPS fiber nonwoven fabric. The fine particles of unstretched PPS fiber non-woven fabric trapped fine particles, while the chemical-resistant fiber fabric collected coarse particles to provide a filter having excellent pressure resistance while maintaining filtration accuracy.

[0039]

[Table 2]

[0040]

As described above, the chemical resistant composite fabric of the present invention has sufficient shape retention to withstand the intended use while maintaining chemical resistance and heat resistance. Furthermore, when used as a molded article, particularly a filter, the chemically resistant composite fabric of the present invention captures both coarse particles and fine particles, and thus has extremely high filtration accuracy. In addition to filters, it can be used in various fields of industrial materials.

Claims (6)

[Claims] 1. A non-woven polyphenylene sulfide fiber non-woven fabric having a fiber diameter of 10 μm or less and a fabric made of chemical resistant fibers having a fiber diameter of 15 μm or more are laminated, and both are entangled at least at a lamination boundary. Combined
A chemical resistant composite fabric characterized in that the contact points between the fibers are adhered and fixed. 2. The chemical-resistant composite fabric according to claim 1, wherein the nonwoven fabric of polyphenylene sulfide fiber and the chemical-resistant fiber fabric are entangled by a water flow. 3. The chemical-resistant composite fabric according to claim 1, wherein the chemical-resistant fiber fabric is a polyphenylene sulfide fiber. 4. A non-woven fiber aggregate, comprising:
The at least one kind selected from a knitted fabric and a woven fabric.
4. The chemical-resistant composite fabric according to any one of items 1 to 3. 5. The chemical-resistant composite fabric according to claim 4, wherein the nonwoven fiber aggregate is at least one selected from a long-fiber nonwoven fabric, a short-fiber nonwoven fabric, and a web aggregate. 6. A molded article using the composite fabric according to any one of claims 1 to 5.