KR102162025B1 - Wetlaid electret nonwoven fabric made of electret powders and fibers - Google Patents

Abstract

The present invention relates to a wet electrostatic nonwoven fabric composed of electrostatic powder and electrostatic fibers, and more particularly, electrostatic powder having an average particle diameter of 20 nm to 200 μm and an electrostatic material containing 0.05-3% by weight of electrostatic material and 0.05-10% by weight of electrostatic material As a wet electrostatic nonwoven fabric composed of ultra-fine electrostatic fibers having an average diameter of 0.5 to 10 μm contained in %, it relates to a wet electrostatic nonwoven fabric having very excellent filtering ability for fine particles and ultrafine dust.

Description

Wetlaid electret nonwoven fabric made of electret powders and fibers}

The present invention relates to a wet electrostatic nonwoven fabric made of electrostatic powder and electrostatic fibers, and more particularly, as a wet electrostatic nonwoven fabric manufactured using electrostatic fibers in which a dielectric material is mixed with electrostatic powder and ultrafine fibers. It relates to a wet electrostatic nonwoven fabric having a very excellent filtration ability against water.

In general, a wet nonwoven fabric is manufactured to serve as a filter, and a filter can achieve its purpose only when it has excellent filtration capability.

Existing materials or filters applied as wet non-woven fabrics are mainly exhibiting filtration effect due to mechanical action, but recently, as fine dust has emerged as a large social problem, we have encountered a problem that fine dust cannot be filtered only by mechanical filtration.

Therefore, in recent years, research on a filter having an electrostatic effect has been conducted in order to filter fine dust particles or fine dust. However, the filters for electrostatic filtration include film cutting & carding (Film) short fibers, spinning short fibers (dry nonwoven fabric), meltblown, spunbond, spunlace, solvent nanospinning, melting. Various types of electrostatic fibers, such as nano spinning, have been developed and progressed. However, such a filter for electrostatic filtration has a problem in that it is not practical and does not properly exert a filtration effect because the holding period of static electricity carrying an electric charge is very short. In addition, recently, there was a problem with emulsion cleaning in developing an electrostatic nonwoven fabric as a wet nonwoven fabric.

As a filter for filtering fine dust, etc., in Korea Patent Application Publication No. 10-2002-0081152, (a) polyvinylidene fluoride (PVDF) and polypropylene (PP: polypropylene) are mixed and spun. A fiber manufacturing step of manufacturing fibers, (b) a polarization treatment step of improving the dielectric constant by polarizing the fibers produced in the fiber manufacturing step, and (c) a nonwoven fabric manufacturing a nonwoven fabric with fibers having an improved dielectric constant in the polarization treatment step A method of manufacturing a high-k nonwoven fabric comprising a step and an electrostatic filter manufactured therefrom are disclosed. In Korean Patent Laid-Open No. 10-2017-0074334, fibers manufactured by mixing and spinning a polypropylene polymer and a dielectric inorganic material are disclosed. As an electrostatic filter manufactured by using, there is disclosed a high efficiency electrostatic filter capable of maintaining filtration for a long time by maintaining an electrostatic force for a long period of time by excellent filtration performance for fine particle size dust and the like.

In addition, in Korean Patent Registration No. 10-1126310, manufacturing a non-woven fabric laminate in which a melt blown non-woven fabric made of non-conductive thermoplastic fibers and a nano web are laminated, and charging the non-woven fabric laminate by spraying high-pressure water. , Drying the charged nonwoven fabric laminate, and a method of manufacturing an electrostatic nonwoven fabric for charging the dried nonwoven fabric laminate by corona discharge.

And in Korea Patent Registration No. 10-1919253, a sheath containing 0.2 to 5% by weight of at least one dielectric powder selected from BaTiO ₃ or PMMA in 95 to 99.8% by weight of polypropylene having a melt index of 20 to 36 g/10min; And , A core part made of polyester having an intrinsic viscosity of 0.6 to 1.2; as a core fiber for manufacturing an electrostatic filter including a dielectric powder consisting of, the sheath and the core part are composed of 20 to 50: 80 to 50% by weight, and the single fiber fineness is 0.5 It is proposed about an electrostatic filter for manufacturing an electrostatic filter including a dielectric powder composed of ~ 20 denier deep microfilament type monofilament, and an electrostatic filter containing the same. In this case, there is a difficulty in manufacturing deep weed yarn, etc., and there is an uneconomic problem that is expensive because the process is complicated.

As described above, the conventional inventions have a problem in that the electrostatic effect is not properly exhibited due to the use of mixed spinning of fibers including a dielectric material, deep weaving, etc., and thus it is difficult to achieve a sufficient purpose.

Korean Patent Publication No. 10-2002-0081152 Korean Patent Publication No. 10-2017-0074334 Korean Patent Publication No. 10-2017-0074334 Korean Patent Registration No. 10-1919253

In order to improve the problems of the prior art as described above, the present invention uses ultra-fine fibers that have superior adsorption properties compared to the previously used wet electrostatic nonwoven fabrics, and manufactures a wet electrostatic nonwoven fabric with high efficiency filter performance in a simple and economical method. As a solution.

Accordingly, an object of the present invention is to provide a wet electrostatic nonwoven fabric manufactured using an electrostatic powder material and an electrostatic fiber in which a dielectric material is mixed at the time of manufacturing an ultrafine fiber.

In addition, another object of the present invention is to provide a highly efficient wet electrostatic nonwoven fabric that exhibits a maximum electrostatic effect while using a minimum dielectric component, and can be manufactured by a simple and economical method.

In order to solve the above problems, the present invention provides an electrostatic powder containing 99.95-90% by weight of the synthetic resin powder and 0.05-10% by weight of the dielectric powder, and 0.05-3% by weight of a dielectric component in a fiber having an average diameter of 0.5-10㎛. It provides a wet electrostatic nonwoven fabric consisting of electrostatic powder and electrostatic fibers, including ultrafine electrostatic fibers contained in %.

In addition, the present invention comprises the steps of preparing an electrostatic powder by mixing 99.95-90% by weight of synthetic resin powder and 0.05-10% by weight of dielectric powder; Preparing ultra-fine electrostatic fibers having an average diameter of 0.5-10 μm containing a dielectric component in an amount of 0.05-3% by weight; And it provides a method of manufacturing a wet electrostatic nonwoven fabric made of electrostatic powder and electrostatic fibers comprising the step of manufacturing a wet nonwoven fabric using the electrostatic powder and ultra-fine electrostatic fibers.

The wet electrostatic nonwoven fabric according to the present invention produces ultra-fine electrostatic fibers by mixing and using a dielectric component as an electrostatic component, and by using these electrostatic fibers and electrostatic powder into a nonwoven fabric, a wet electrostatic nonwoven fabric can be manufactured simply. It is possible to economically manufacture a filter manufactured by fixing it on an ultra-fine electrostatic fiber nonwoven fabric using powder, and has the effect of filtering fine substances with high efficiency.

In addition, in applying the dielectric powder component as an electrostatic material, since it is mixed with synthetic resin and manufactured with ultra-fine fibers, the amount of use is minimized and the maximum electrostatic effect can be obtained even for long-term use. There is a possible advantage.

Hereinafter, the present invention will be described in more detail as one embodiment.

The present invention is not limited to the embodiments disclosed below, but may be modified or implemented in various different forms, and the following embodiments are intended to complete the disclosure of the present invention, and to those of ordinary skill in the art. It is provided to fully inform the category.

Accordingly, embodiments of the inventive concept should not be construed as being limited to a specific shape or component of the region disclosed in the present specification, but should include, for example, a change in shape resulting from manufacturing.

The present invention relates to a wet electrostatic nonwoven fabric composed of electrostatic powder and electrostatic fibers.

According to a preferred embodiment of the present invention, as the electrostatic powder, an electrostatic powder containing 0.05-10% by weight of a dielectric powder in a synthetic resin powder selected from polyethylene, polypropylene or a mixture thereof is used, and the electrostatic powder is used as an ultrafine fiber. It is contained in an amount of 0.05-3% by weight in the made electrostatic fiber.

Here, the electrostatic fiber is preferably an ultra-fine electrostatic fiber containing a dielectric component in an amount of 0.05-3% by weight of the total weight.

Therefore, the wet electrostatic nonwoven fabric according to the present invention may be contained in a form in which the electrostatic powder is dispersed between the ultrafine electrostatic fibers made of the nonwoven fabric.

According to a preferred embodiment of the present invention, the fibers used in the ultrafine fibers of the present invention may be made of a thermoplastic resin as a synthetic resin, and preferably a molten thermoplastic resin. Examples of the molten thermoplastic resin may be made of a molten olefin-based thermoplastic resin, more preferably a polyethylene (PE) or polypropylene (PP) resin.

As the synthetic resin used for the ultrafine fibers of the present invention, the thermoplastic resin may be various known thermoplastic resins. Specific examples of such a thermoplastic resin include a single or a copolymer of ethylene, propylene, 4-methyl-1-pentene, and α-olefin. More specifically, polyolefins such as low-density polyethylene, linear low-density polyethylene (LLDPE), high-density polyethylene, polypropylene (propylene homopolymer), polypropylene random copolymer, poly4-methyl-1-pentene, ethylene-propylene random copolymer, etc. Can be mentioned. In addition, as another example of the thermoplastic resin, polycarbonate such as vinyl isofluoride (PVDF), polymethyl methacrylate (PMMA), polytetrafluoroethylline (PTFE), or a mixture thereof may be exemplified.

According to the present invention, the ultra-fine fibers may have the form of composite mixed fibers manufactured by mixing the synthetic resin components.

The synthetic resin component for manufacturing such ultrafine fibers is a main component in the manufacture of fibers, and preferably those having a melt index of 15 to 40 g/10min can be easily mixed in the mixing process with the dielectric component, which is an electrostatic material. In addition, the dielectric effect can be preferably exhibited after being made of ultrafine fibers.

According to a preferred embodiment of the present invention, an ultrafine fiber is prepared by mixing a synthetic resin component and a dielectric component, wherein the dielectric component mixed with the synthetic resin is mixed at 0.05-3% by weight of the synthetic resin to prepare ultrafine electrostatic fibers. have.

According to a preferred embodiment of the present invention, as the dielectric component, at least one dielectric component selected from polyvinylidene fluoride (PVDF), polymethyl methacrylate (PMMA), hindered amine light stabilizer (HALS), triazine, BaTiO ₃ Can be used. However, since other dielectric components can be used, it is limited thereto. In particular, HALS usable in the present invention is used as a light stabilizer that prevents modification of a polymer by reducing or stopping a photochemical reaction due to UV, and most HALS are known to have properties as a dielectric.

According to a preferred embodiment of the present invention, a synthetic resin and a dielectric component are mixed in this way to prepare and use ultra-fine fibers having an average diameter of 0.5-10 μm. Ultra-fine electrostatic fibers having such electrostatic properties are ultra-fine fibers with a small average diameter, unlike electrostatic fibers that have been used by manufacturing dielectric powder as fibers. Therefore, the electrostatic area is superior to those of fibers having a large average diameter. It has a very excellent adsorption effect due to the non-woven fabric composition of the wider and very fine ultra-fine electrostatic fibers.

In the present invention, the term "ultra-fine fiber" refers to a fiber made of microfiber, microfiber, decomposed yarn, island-in-the-sea yarn, and the like.

According to a preferred embodiment of the present invention, the ultrafine fiber is a single ultrafine fiber, split yarn or island-in-the-sea yarn; Or PP/PE, PET/PE, PET/PP, or PC Sheath/Core or Side by Side type composite melting point fibers selected from one or more synthetic fibers. The ultrafine fibers are preferably those having a melting point of 110-270° C. and an average diameter of 0.5-10 μm.

In the present invention, split yarn or island-in-the-sea yarn can be used by reducing alkali and washing by putting several% of a hydrophilic material, and ultrasonic dispersion can be performed to facilitate dispersion in a wet nonwoven fabric.

The synthetic fibers usable in the present invention are not limited thereto, and composite ultrafine fibers made of other forms or other similar components similar to this may be used.

If the average diameter of the ultrafine fibers is too large, the fine dust removal effect and adsorption effect are greatly reduced, and if the average diameter is too small, there may be uneconomical problems such as difficulty in manufacturing the ultrafine fibers and the nonwoven fabric.

According to a preferred embodiment of the present invention, since the ultrafine fiber is a fiber that is hydrophilic in water and becomes hydrophobic when dried, it is possible to hydrophobize without a water repellent, and because it is used after fiberization in water, there is no oil and no dielectric material is used. Even if it is mixed and manufactured into electrostatic fiber, it does not interfere with the characteristics of the electrostatic fiber.

In addition, since the ultra-fine fiber according to the present invention has a hydrophobic property after being manufactured and dried, it has strong water repellency, so when applied as a filter, it is possible to manufacture it as a filter media (filter fabric) that can be washed continuously for repeated use. There is this.

Therefore, it is very efficient and economical for the filtering effect of fine dust and ultra-fine dust through the composition of non-woven fabric using ultra-fine fibers containing such an electrostatic material, and changes in long-term use due to not using a separate electrostatic powder. It has excellent effects even in the absence of durability.

According to the present invention, when manufacturing a wet nonwoven fabric exhibiting an electrostatic effect, an electrostatic material is mixed in the manufacturing process of an ultra-fine fiber to form a fiber into an ultra-fine fiber, but not a normal fiber, but an ultra-fine fiber having a specific diameter or less. Compared to the case of applying a dielectric material or applying the electrostatic powder to the nonwoven fabric of general fiber, the electrostatic effect is far superior.

In addition, since the wet electrostatic nonwoven fabric according to the present invention exists in the form of ultra-fine fibers having a large surface area, it exhibits an effect of widening the contact surface to the ultra-fine particles, and thus has a very excellent filter effect.

A method of manufacturing a wet electrostatic nonwoven fabric made of electrostatic fibers according to the present invention will be described in more detail.

According to the present invention, a step of preparing an electrostatic powder by mixing a synthetic resin powder and a dielectric powder is performed.

In this process, 99.95-90% by weight of synthetic resin powder and 0.05-10% by weight of dielectric powder may be mixed to prepare electrostatic powder. According to a preferred embodiment of the present invention, the electrostatic powder produced at this time may be prepared as an electrostatic powder having an average particle diameter of 20 nm to 200 μm. Only then has desirable properties for application to a nonwoven fabric made of ultra-fine electrostatic fibers.

Separately, a step of producing ultra-fine electrostatic fibers is performed by mixing a dielectric component in the manufacturing process of the ultra-fine fibers.

Here, 0.05-3% by weight of a dielectric component is mixed with 99.95-97% by weight of synthetic resin to prepare ultra-fine electrostatic fibers having an average diameter of 0.5-10 μm.

In the step of mixing the dielectric component with the synthetic resin to produce an ultra-fine fiber, which is an electrostatic fiber, it may be produced into an ultra-fine fiber by a conventional method.

According to the present invention, since the ultra-fine electrostatic fiber thus produced is manufactured into an ultra-fine fiber by mixing a dielectric component in the fiber manufacturing process, it exhibits electrostatic properties by itself. In particular, since the ultrafine electrostatic fiber of the present invention is an ultrafine fiber whose fiber average diameter is very small compared to the previous one, the electrostatic property is more excellent due to the increased external exposure of the mixed dielectric material, and the large surface area and adsorption characteristics of the ultrafine electrostatic fiber itself It has excellent fine dust absorption ability. Therefore, in the case of manufacturing a nonwoven fabric using a mixed ultrafine electrostatic fiber as an electrostatic material in the ultrafine fiber and using it as an electrostatic wet nonwoven fabric, the adsorption properties of ultrafine particles such as ultrafine dust are very excellent.

According to the present invention, the wet electrostatic nonwoven fabric may contain electrostatic powder. The electrostatic powder contained at this time may be contained in an amount of 0.05-3% by weight in the total wet electrostatic nonwoven fabric.

In this case, the available electrostatic powder may be a conventional dielectric powder as it is, or a synthetic resin powder and a dielectric powder may be combined into one powder by wet-laid mixing to form an electrostatic powder. In the case of mixed electrostatic powder, the synthetic resin powder exerts adhesive strength in the wet mixing process, so that the dielectric powder adheres to the synthetic resin powder to form a single powder unit, or it may be composed of an electrostatic powder in the form of coating on the dielectric powder or synthetic resin powder. Therefore, even after the electrostatic powder is manufactured, the dielectric powder hardly maintains the external shape of the powder, but adheres to the fiber, and the surface area of the dielectric powder is enlarged, so that it can be formed into a fiber that is fixed on the fiber.

According to a preferred embodiment of the present invention, the wet electrostatic nonwoven fabric made of the ultrafine electrostatic fibers is an electrostatic powder in the electrostatic fiber, and the dielectric powder is contained in an amount of 0.05-10% by weight in a synthetic resin powder selected from polyethylene, polypropylene, or a mixture thereof. The electrostatic powder is contained in the wet nonwoven fabric, but the electrostatic powder may be contained in the form of being dispersed in the ultrafine electrostatic fibers of the wet nonwoven fabric in an amount of 0.05-3% by weight of the total weight.

According to a preferred embodiment of the present invention, the wet electrostatic nonwoven fabric manufactured by the wet nonwoven manufacturing process as described above has a unit weight of 30 to 150 g/m ² , a thickness of 0.1 to 1.0 mm, and the air permeability is filtration efficiency and ventilation. In consideration of pressure, economy, etc., it may be preferably manufactured to be 20 to 250 cm ³ /cm ² /sec.

According to a preferred embodiment of the present invention, when the unit weight of the wet nonwoven fabric is less than 30 g/m2, the nonwoven fabric is too thin, so the strength may be too weak, and when it exceeds 100 g/m2, the pressure loss of the nonwoven fabric is excessive. There is a risk of increasing.

Further, according to a preferred embodiment of the present invention, the thickness of the wet electrostatic nonwoven fabric is the most excellent in terms of strength and filtration efficiency in the range of 0.1 to 1 mm.

According to the present invention, the wet electrostatic nonwoven fabric prepared as described above is subjected to a charge treatment on the surface of the nonwoven fabric through a corona discharge treatment process using a wire-shaped or plate-shaped electrode to form a large amount of cations or anions.

According to a preferred embodiment of the present invention, in order to charge the surface of the nonwoven fabric, an electrostatic treatment step of performing corona discharge treatment may be additionally performed. In this corona discharge, if the voltage is raised while supplying power to the DC high voltage generator, a corona discharge occurs at the tip of the settling electrode, and a high field is formed between the flat electrode and the settling electrode. Therefore, the nonwoven fabric passing between the flat electrode and the settling electrode is There is a high charge on the surface.

According to a preferred embodiment of the present invention, the corona discharge applied to the wet electrostatic nonwoven fabric is preferably performed with an applied voltage of 10 to 100 kV. In addition, the voltage application time for corona discharge is preferably 1 to 7 minutes. As described above, the amount of charge applied to the entire surface of the nonwoven fabric is increased by the corona discharge.

When the corona discharge treatment is performed as described above, the electrostatic force relative to the same weight of the fiber may be increased by 20 to 70% by the electrostatic treatment. Therefore, it is possible to improve a problem in that the dust collection efficiency is deteriorated due to the loss of electric charge as fine dust adsorbed for a long period of time during use after the filter is manufactured is accumulated.

According to the present invention, the wet electrostatic nonwoven fabric manufactured through such a series of processes has excellent static electricity retention, and the dust collection efficiency is not reduced even when used for a long period of time, so that it is possible to manufacture a wet electrostatic nonwoven fabric having excellent filtering effect.

The wet electrostatic nonwoven fabric manufactured according to the present invention may be manufactured and used as an electrostatic filter through an appropriate process after corona discharge treatment as described above.

The filter using a wet electrostatic nonwoven fabric made of electrostatic fibers manufactured according to the present invention has excellent static electricity retention because it has electrostatic properties in the national fibers. In particular, the surface area is very large, so it can prevent fine particles such as fine dust as well as ultrafine dust. The filtration efficiency is significantly superior to the conventional filter.

In addition, unlike the conventional electrostatic filter, which has problems such as a rapid decrease in collection efficiency or desorption of electrostatic powder when used due to the use of a dielectric material in a fibrous form, the filter manufactured using the wet electrostatic nonwoven fabric substrate of the present invention Since the material is present in the very fine fiber, there is no loss of static electricity, and the surface area is very large, so that the collection efficiency is excellent, and the collection efficiency is not reduced, and the effect of being maintained for a long time can be expected.

In particular, according to the present invention, in manufacturing electrostatic powder and electrostatic fiber, since it is manufactured with ultra-fine electrostatic fiber as an electrostatic fiber and manufactured with a wet nonwoven fabric, it is possible to easily manufacture it, thereby increasing the price competitiveness of the wet electrostatic nonwoven fabric. have.

In addition, the wet electrostatic nonwoven fabric according to the present invention can be manufactured economically as described above, and has an effect of exhibiting more excellent dust collection efficiency due to the microstructure made of fine electrostatic powder and ultra-fine electrostatic fibers.

Filters such as various air filters can be manufactured by using the wet electrostatic nonwoven fabric made of the fine electrostatic powder and ultrafine electrostatic fibers according to the present invention as described above.

These wet electrostatic nonwovens can be combined with a single layer or other similar laminates to form a multilayered laminate.

The filter using a wet electrostatic nonwoven fabric made of electrostatic fibers according to the present invention can be used as an industrial, automobile, and household filter for air purification in various forms.

Hereinafter, the present invention will be described in detail by examples, but the present invention is not limited by the examples.

Example 1

By compounding 98.5% by weight of PE/PET resin with a melt index of 32g/10min and 1.5% by weight of BaTiO ₃ as a dielectric component, a PE/PET composite ultra-fine electrostatic fiber with an average diameter of 2.0㎛ and a fiber length of 6mm is prepared as an electrostatic fiber. Was prepared.

Wet-laid non-woven fabric with a unit weight of 100 g/m ² , a thickness of 0.5 mm, and an air permeability of 70 cm ³ /cm ² /sec by using an electrostatic fiber in the form of ultra-fine fibers thus prepared. Was prepared. Here, a fine electrostatic powder (Powder in which 1.5% by weight of BaTiO ₃ is mixed as a dielectric material in PE powder) is added to the non-woven fabric prepared as described above to be cut into 20 cm X 20 cm size and continuous corona discharge. A wet electrostatic nonwoven fabric was manufactured by processing for 3 minutes at a maximum processing speed of 20 m/min and an output of 30 kV in a room temperature atmosphere using a processing equipment.

Example 2

By compounding 98.5% by weight of PE/PET resin with a melt index of 32g/10min and 1.5% by weight of BaTiO ₃ as a dielectric component, a PE/PET composite ultrafine electrostatic fiber with an average diameter of 10.0㎛ and a fiber length of 6mm is used as electrostatic fiber. Was prepared.

Wet-laid non-woven fabric with a unit weight of 100 g/m ² , a thickness of 0.5 mm, and a permeability of 100 cm ³ /cm ² /sec by using an electrostatic fiber in the form of ultra-fine fibers thus prepared according to a conventional method. Was prepared. Here, by putting 1.5% of fine electrostatic powder 90㎛ LDPE Powder, the nonwoven fabric prepared as described above is cut into a size of 20 cm X 20 cm, and the maximum processing speed is 20 m/in under room temperature atmosphere using a continuous corona discharge processing device. A wet electrostatic nonwoven fabric was prepared by processing for 3 minutes at an output of min and 30 kV.

Example 3

PP/PET composite ultra-fine electrostatic fiber with an average diameter of 2.0㎛ and a fiber length of 6mm by compounding 98.5% by weight of PP/PET resin with a melt index of 32g/10min and 1.5% by weight of hindered amine as a dielectric component. Was prepared.

Wet-laid with a unit weight of 100 g/m ² , a thickness of 0.5 mm and an air permeability of 70 cm ³ /cm ² /sec by using an electrostatic fiber in the form of ultrafine fibers thus prepared according to a conventional method. A nonwoven fabric was prepared. The nonwoven fabric prepared as described above is cut into 20 cm X 20 cm size by adding 1.0% of fine electrostatic powder 40㎛ LDPE Powder, and the maximum processing speed is 20 m/min under room temperature atmosphere using a continuous corona discharge processing equipment. , A wet electrostatic nonwoven fabric was prepared by processing for 3 minutes at an output of 30 kV.

Example 4

PP/PET composite ultra-fine electrostatic fiber with an average diameter of 10.0㎛ and a fiber length of 6mm by compounding 98.5% by weight of PP/PET resin with a melt index of 32g/10min and 1.5% by weight of hindered amine as a dielectric component. Was prepared.

Using the electrostatic fiber in the form of ultra-fine fibers thus prepared, a wet-laid nonwoven fabric having a unit weight of 100 g/m ² , a thickness of 0.5 mm and an air permeability of 120 cm ³ /cm ² /sec according to a conventional method. Was prepared. Here, by putting 1.5% of fine electrostatic powder 200㎛ LDPE Powder, the nonwoven fabric prepared as above is cut into a size of 20 cm X 20 cm, and the maximum processing speed is 20 m/min under a room temperature atmosphere using a continuous corona discharge processing device, Treatment for 3 minutes at an output of 30 kV was performed to prepare a wet electrostatic nonwoven fabric.

In the same manner as in Example 1 above, a dielectric powder was used as shown in the following table and conditions were changed to prepare ultra-fine electrostatic fibers, and then a wet electrostatic nonwoven fabric was prepared by constituting the nonwoven fabric.

Comparative Example 1

Conducted in the same manner as in Example 1, except that electrostatic powder was not prepared, and when PE/PET fiber was produced, the average diameter of the fiber was 10 µm and short fibers of 6 mm length were prepared, and the unit weight was 100 g/s according to a conventional method. m ² , a thickness of 0.5 mm, and an air permeability of 100 cm ³ /cm ² /sec to prepare a wet-laid nonwoven fabric. This was used to manufacture a wet nonwoven fabric to prepare a wet electrostatic nonwoven fabric.

2 in comparison

Polypropylene masterbatch was prepared by compounding 97% by weight of PP/PET with a melt index of 30 g/10min and 3% by weight of hindered amine as a dielectric powder. In addition, the master batch was prepared by spinning and stretching a 75/36 deir core yarn with a polyester having an intrinsic viscosity of 1.0 as a core portion and a core portion having an intrinsic viscosity of 1.0. At this time, the sheath part and the core part are composed of 30:70 in a weight ratio, and after that, the core sheath is manufactured with a short fiber having a fiber diameter of 10 μm and a fiber length of 6 mm, and the unit weight is 120 g/m ² based on a conventional method. And a wet-laid nonwoven fabric having a thickness of 0.6 mm and an air permeability of 70 cm ³ /cm ² /sec was prepared. The nonwoven fabric prepared as described above was cut into a size of 20 cm X 20 cm and treated for 3 minutes at a maximum processing speed of 20 m/min and 30 kV in an oxygen atmosphere using a continuous corona discharge processing device to prevent the electrostatic discharge of the present invention. A nonwoven base material for filter production was prepared and used as a test piece.

Experimental example

A filtration test was performed according to the NaCl aerosol test method in order to test the filtering ability of ultrafine dust of the wet electrostatic nonwoven fabric containing the dielectric powder for manufacturing the electrostatic filter prepared according to the above Examples and Comparative Examples.

It was tested with a surface speed of 5.3 cm/sec with 0.3 μm of NaCl particles. The test equipment was measured using a model TSI 8130 filter tester. This was carried out by the above method as a method of measuring the amount of sodium chloride remaining in the air after passing through the filter to be tested, and the filtration rate was expressed as a percentage (%).

In this experiment, the initial filtration rate and the long-term filtration rate, which is the filtration rate of the test piece after 120 days, were measured for the nonwoven test pieces of the above Examples and Comparative Examples. After measuring the filtration rate of the test piece in the same manner as described above, it is shown in Table 1 below.

Here, the environmental resistance efficiency was measured after repeated use twice, such as -40°C, 8 hours, +80°C 8 hours.

division Electrostatic powder Ultrafine
fiber Fiber diameter
(㎛) weight
(g/m ² ) thickness
(mm) Ventilation
(cc/cm ² /sec) Early
percolation
efficiency
(%) Environment
percolation
efficiency
(%) blackout
matter powder
size
(㎛) content
(%) Example 1 BaTiO ₃ 200 1.5 PE/PET 10 100 0.5 120 95.34 93.27 Example 2 BaTiO ₃ 90 1.5 PE/PET 10 100 0.5 100 99.92 98.31 Example 3 Hindered amine 40 1.0 PP/PET 2.0 100 0.5 70 99.95 99.91 Example 4 200 1.5 PP/PET 10 100 0.5 120 94.01 93.43 Comparative Example 1 x x x PE/PET
Non-blackout 10 100 0.5 100 40.45 39.05 Comparative Example 2 X X X PP/PET 10 120 0.6 70 86.49 79.63

As a result of the above experiment, in the case of the wet electrostatic nonwoven fabric of Examples 1-4 according to the present invention, all of the initial filtration rates were measured to be 94% or more, but in the case of the comparative example, the initial filtration rates were measured to be low. In addition, even in the case of the filtration rate of the environmental resistance test piece, it was measured that the filtration rate decreased by about 2.0% in the case of the example, but in the case of the test piece of the comparative example, when the measurement test piece was a non-static material, the filtration efficiency was very low, and the electrostatic powder The non-injected wet nonwoven fabric was also measured to significantly decrease the filtration efficiency.

From the results of Table 1 above, when the nonwoven fabric substrate according to the present invention is used as an electrostatic filter, the filtration performance is superior to that of the conventional filter, and the performance is maintained at an almost initial level even in the environment-resistant, so that the lifespan is significantly improved compared to the conventional filter. I can see that it is.

Although the present invention has been described as one embodiment, this is only illustrative, and those of ordinary skill in the art will appreciate that various modifications and equivalent other experimental examples are possible therefrom. Therefore, the true technical scope of the present invention should be determined by the technical spirit of the appended claims.

Claims (9)

An electrostatic powder having an average particle diameter of 20 nm to 200 μm containing 0.05 to 10% by weight of the dielectric component powder in 99.95 to 90% by weight of synthetic resin powder, and
The average diameter is 0.5 to 10 ㎛, the dielectric component is contained in an amount of 0.05 to 3% by weight, a single microfiber, split yarn or island-in-the-sea yarn; Or ultra-fine electrostatic fiber made of one or more synthetic fibers selected from Sheath/Core or Side by Side type composite melting point fibers selected from PP/PE, PET/PE, PET/PP or PC
Including, wherein the electrostatic powder is fixed to the ultra-fine electrostatic fiber, characterized in that the wet electrostatic nonwoven made of electrostatic powder and electrostatic fiber.
delete The method according to claim 1, wherein the synthetic resin component constituting the ultrafine electrostatic fiber is low density polyethylene, linear low density polyethylene (LLDPE), high density polyethylene, polypropylene (propylene homopolymer), polypropylene random copolymer, poly4-methyl-1-pentene, A wet electrostatic nonwoven fabric comprising an electrostatic powder and an electrostatic fiber, characterized in that it is any one selected from ethylene-propylene random copolymer and polycarbonate, or a mixture of two or more.
The electrostatic powder according to claim 1, wherein the dielectric component is at least one dielectric component selected from polyvinylidene fluoride (PVDF), polymethyl methacrylate (PMMA), hindered amine light stabilizer (HALS), and BaTiO ₃ And a wet electrostatic nonwoven fabric made of electrostatic fibers.
The wet electrostatic nonwoven fabric according to claim 1, comprising electrostatic powder and electrostatic fibers in which the electrostatic powder is contained in an amount of 0.05-3% by weight in ultrafine electrostatic fibers.
The wet electrostatic nonwoven fabric according to claim 1, comprising an electrostatic powder and an electrostatic fiber, which is subjected to corona discharge treatment.
Preparing an electrostatic powder by mixing 99.95-90% by weight of synthetic resin powder and 0.05-10% by weight of a dielectric component powder;
It contains a dielectric component in an amount of 0.05-3% by weight and has an average diameter of 0.5-10 μm, and is a single microfiber, split or island-in-the-sea yarn; Or preparing ultra-fine electrostatic fibers made of one or more synthetic fibers selected from Sheath/Core or Side by Side composite melting point fibers selected from PP/PE, PET/PE, PET/PP, or PC; And
Manufacturing a wet nonwoven fabric with the electrostatic powder adhered to the ultrafine electrostatic fiber
Method for producing a wet electrostatic nonwoven fabric consisting of electrostatic powder and electrostatic fibers comprising a.
The method according to claim 7, comprising electrostatic powder consisting of electrostatic fibers and electrostatic fibers further comprising performing corona discharge treatment after manufacturing a wet nonwoven fabric, but performing corona discharge at an applied voltage of 10 to 100 kV for 1 to 7 minutes. Method for producing a wet electrostatic nonwoven fabric.
A filter comprising a wet electrostatic nonwoven fabric made of electrostatic powder and electrostatic fibers according to any one of claims 1 and 3 to 6.