KR102563110B1 - Nanofiber filter and preparation method thereof - Google Patents

Abstract

According to the present invention, two or more kinds of spinning solutions including polymers having different concentrations or different weight average molecular weights, and two or more kinds of first nozzle parts and second nozzle parts into which the two or more kinds of spinning solutions can be alternately introduced are provided. A method for manufacturing a nanofiber filter comprising the step of forming a sheet including first nanofibers and second nanofibers having different diameters on a substrate using a spinning device, and a nanofiber filter formed by this method are provided. do.

Description

Nanofiber filter and its manufacturing method {NANOFIBER FILTER AND PREPARATION METHOD THEREOF}

The present invention relates to a nanofiber filter that has a low density, is advantageous in differential pressure, and has an increased thickness compared to the same basis weight to increase dust collection capacity and a method for manufacturing the same.

A filter is a filtering device that filters out foreign substances in a fluid, and is divided into a liquid filter and an air filter. Among them, air filters can be used in air purifiers, air conditioners, air conditioners, inside vehicles, etc. to remove biologically harmful substances such as fine dust, particulates, biological particles such as germs and molds, and bacteria in indoor air such as homes and offices. With the development of the industry, it can be applied to the installation of a clean room to prevent defects of high-tech products.

In addition, the air filter may be made of a nanofiber filter, and most of the nanofiber filter is a sheet composed of a similar diameter, or a multi-layered sheet after manufacturing a sheet with different fiber diameters. It is produced with multi-layer filter media.

The pore size and density of the nanofiber filter are mostly determined by the fiber diameter, and as the fiber diameter decreases, the pore size decreases and the density increases, and the thickness tends to decrease for the same basis weight. Therefore, when the fiber diameter is determined, there are limitations in controlling the pore size and density. In addition, if the thickness of the nanofiber filter is too thin, a large amount of dust cannot be collected, so the size of the filter must be widened.

Therefore, it is required to develop a nanofiber filter having a thickness and area capable of increasing dust collection efficiency.

An object of the present invention is to provide a nanofiber filter suitable for use as an air filter for dust collection that is advantageous in differential pressure and can lower the density and increase the thickness compared to the prior art for the same basis weight by manufacturing a sheet with various pore sizes and a manufacturing method thereof It is to do.

Another object of the present invention is to provide a nanofiber filter and a manufacturing method thereof capable of increasing dust collection efficiency compared to conventional nanofiber filters composed of only one type of fiber having a larger basis weight.

According to one embodiment of the present invention,

Two or more kinds of spinning solutions including polymers having different concentrations or different weight average molecular weights;

Using a spinning device having at least two first nozzle parts and a second nozzle part into which the two or more kinds of spinning solutions can be alternately injected,

Forming a sheet including first nanofibers and second nanofibers having different diameters on a substrate

It provides a method for manufacturing a nanofiber filter comprising a.

In addition, according to another embodiment of the present invention, a substrate; and a first nanofiber and a second nanofiber having different diameters dispersed on the substrate.

The present invention prepares two types of spinning solutions using the same polymer to have different concentrations or different weight average molecular weights, and then alternately injects them into two or more nozzle parts and spins them on the substrate, thereby forming a network on the substrate. A sheet in which nanofibers having two different diameters are dispersed can be prepared. The nanofiber sheet manufactured in this way provides an advantageous effect on pressure differential because a fiber web having a more diverse pore size than before is formed on the substrate. In addition, the nanofiber sheet of the present invention has a low density and an increased thickness compared to the same basis weight as in the prior art, so the dust collection capacity is greatly improved, so it is suitable for use as an air filter.

1 schematically illustrates a manufacturing process diagram of a nanofiber filter according to an embodiment of the present invention.
Figure 2a schematically illustrates a manufacturing process diagram of a nanofiber filter according to another embodiment of the present invention.
FIG. 2B is a simplified perspective view of the spinning device used in FIG. 2A.
Figure 3a is a FE-SEM picture of the nanofiber filter of Example 1.
Figure 3b is a FE-SEM picture shown by changing the magnification of the nanofiber filter of Example 1.
4 is a FE-SEM picture of the nanofiber filter of Comparative Example 1.
5 is a FE-SEM picture of the nanofiber filter of Comparative Example 2.
Figure 6 is a graph comparing the pore size distribution with respect to the diameter of Example 1 and Comparative Example 2.
7 is a FE-SEM picture of the nanofiber filter of Examples 2 to 4.
8 is FE-SEM pictures of nanofiber filters of Comparative Examples 3, 5 and 7.
9 is FE-SEM pictures of nanofiber filters of Comparative Examples 4, 6 and 8.
10 is a graph comparing pore size distribution with respect to diameter in Example 2 and Comparative Examples 3 to 4.
Figure 11 is a graph comparing the pore size distribution with respect to the diameter of Example 3 and Comparative Examples 5 to 6.
12 is a graph comparing the pore size distribution with respect to the diameter of Example 4 and Comparative Examples 7 to 8.

In the present invention, terms such as first and second are used to describe various components, and the terms are used only for the purpose of distinguishing one component from another.

In addition, terms used in this specification are only used to describe exemplary embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "comprise", "comprise" or "having" are intended to indicate that there is an embodied feature, number, step, component, or combination thereof, but one or more other features or It should be understood that the presence or addition of numbers, steps, components, or combinations thereof is not precluded.

In addition, since the present invention can have various changes and various forms, specific embodiments will be exemplified and described in detail below. However, it should be understood that this is not intended to limit the present invention to the specific disclosed form, and includes all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

According to one embodiment of the invention, two or more kinds of spinning solutions including polymers having different concentrations or different weight average molecular weights, and two or more kinds of first nozzle parts and second kinds of spinning solutions into which the two or more kinds of spinning solutions can be alternately introduced. A method of manufacturing a nanofiber filter may be provided, which includes forming a sheet including first nanofibers and second nanofibers having different diameters on a substrate using a spinning device having a nozzle unit.

Preferably, the method comprises the steps of preparing a first spinning solution and a second spinning solution by dissolving polymers having different concentrations or different weight average molecular weights in solvents; alternately injecting the first spinning solution and the second spinning solution into at least two first nozzle parts and second nozzle parts; And the first and second nanofibers having different diameters on the substrate by spinning the first spinning solution and the second spinning solution on the substrate through the first nozzle unit and the second nozzle unit of the spinning device. Forming a sheet including a; may include.

Hereinafter, a nanofiber filter and a manufacturing method thereof according to an embodiment of the present invention will be described in detail.

In a sheet having the same fiber diameter, it may be advantageous for differential pressure if it is possible to impart various pore sizes. In addition, in a sheet having the same fiber diameter, decreasing the density can increase the thickness relative to the same basis weight, thereby increasing the dust collection capacity.

Therefore, the present invention relates to a method for manufacturing a nanofiber sheet having various sizes of pores in the sheet by preparing the sheet to be composed of two different fiber diameters in order to provide all of the above effects.

In addition, although the sheet of the present invention contains fibers having different diameters, it forms a network-like fiber web rather than a conventional laminated structure. That is, the present invention uses a spinning solution containing two or more different concentrations or different weight average molecular weight polymers, but after repeatedly arranging two or more of them alternately, and then spinning on the substrate, the nanofibers having two different fiber diameters may be entangled with each other and formed in a network type having different pores.

Preferably, the present invention may be a configuration in which the aggregates including the first nanofibers and the second nanofibers having small particle diameters are entangled like a network while being evenly dispersed on the substrate using two types of spinning solutions.

In this case, in the present invention, the first nanofiber is a fiber assembly having a diameter of 1 μm or less, and the second nanofiber means a fiber assembly having a diameter twice or more than the diameter of the first nanofiber. The first nanofiber and the second nanofiber may have an average pore diameter of 0.1 to 10 μm.

Preferably, the ratio of the first nanofiber and the second nanofiber may be 1:1 times or more, and preferably, the ratio may be 1:1 to 1:30 times or 1:1 to 1:3 times.

The ratio of the first nanofiber and the second nanofiber can be calculated as the ratio of the number of nozzles for spinning each nanofiber assembly, the volume ratio of the spun spinning solution, or the weight ratio of the spun spinning solution.

Therefore, the present invention can simultaneously exhibit the effect of reducing density and increasing thickness for the same basis weight compared to the prior art, as well as significantly increasing the pressure differential and dust collection efficiency. In particular, the present invention has the advantage of having a lower differential pressure compared to existing nanofiber sheets composed of a single diameter. The smaller the pore size, the higher the dust removal efficiency and differential pressure, and when the appropriate pore size and packing density are maintained, high efficiency and low differential pressure can be advantageous. In the present invention, two types of nanofiber aggregates are formed on a substrate to exhibit various pore sizes, maintain packing density, and increase thickness to reduce high efficiency and differential pressure.

According to one embodiment of the present invention, the two or more kinds of spinning solutions may be polymer solutions in which the same polymer is used, but selected at different concentrations or different weight average molecular weights and dissolved in a solvent. Preferably, the spinning solution may be used by preparing a first spinning solution and a second spinning solution by dissolving a polymer having a different concentration or different weight average molecular weight in a solvent.

In addition, it is preferable to prepare a sheet by adopting two types of spinning solutions so that the concentration of the polymer solution and the type of polymer are the weight average molecular weight or concentration of the polymer having a difference of more than two times compared to the fiber diameter under the same spinning conditions. .

Therefore, the second spinning solution may be used by adjusting the concentration or weight average molecular weight of the polymer so that the difference is more than twice as large as the fiber diameter prepared using the first spinning solution.

Such a polymer solution includes a polymer and a dispersion solvent, and may include a dispersant and an additive as needed, but the present invention is not limited thereto.

In addition, the first spinning solution may include a polymer having a concentration of 1 to 20% by weight or a weight average molecular weight of 10,000 to 4,000,000. The second spinning solution may include a polymer having a concentration of 10 to 30% by weight or a weight average molecular weight of 10,000 to 4,000,000.

At this time, the composition of the first spinning solution and the second spinning solution may be selected and used under the above conditions so that the diameter of the second nanofiber compared to the first nanofiber is more than twice as large by comparing the fiber diameter in the final sheet.

Preferably, the two or more kinds of spinning solutions include a first solution containing 1 to 20% by weight of a polymer having a weight average molecular weight of 100,000 to 4,000,000, and 10 to 30% by weight of a polymer having a weight average molecular weight of 100,000 to 4,000,000 It may include a second solution included as.

More preferably, the two or more kinds of spinning solutions include a first solution containing 1 to 10% by weight of a polymer having a weight average molecular weight of 100,000 to 1,000,000, and 10 to 20% by weight of a polymer having a weight average molecular weight of 100,000 to 1,000,000 It may include a second solution included in %.

In addition, according to one embodiment of the present invention, the polymer is polyvinylidene fluoride (PVDF), poly acrylonitrile (PAN), polyurethane, polyether sulfone, polyimide, polybutylene At least one selected from the group consisting of succinate, polyethyleneoxide (PEO), polyvinyl alcohol (PVA), polyvinyl chloride (PVC) and polyethylene terephthalate (PET) may include, preferably, polyvinylidene fluoride may be used, but the present invention is not limited thereto.

In addition, according to one embodiment of the present invention, organic solvents such as dimethylacetamide, diethylacetamide, dimethylmethoxyacetamide, N-methylpyrrolidone, and dimethylformamide or water may be used as the dispersion solvent. , the present invention is not limited thereto.

On the other hand, the manufacturing method of the nanofiber sheet of the present invention can be carried out using a general spinning device used in fiber manufacturing.

For example, the spinning apparatus is a nozzle-type spinning apparatus having two or more nozzle parts, such as electro spinning, solution spinning, meltblown spinning, and solution blowing. possible.

That is, the spinning device may include at least two or more types of nozzle units so that polymer solutions under different conditions may be alternately arranged.

According to a preferred embodiment, the present invention may use a solution blowing device in which two or more nozzle parts may be alternately and repeatedly arranged.

According to another embodiment, the present invention may use an electrospinning apparatus having two or more nozzle units. In this case, the electrospinning apparatus includes two or more nozzle parts, and after the first spinning solution and the second spinning solution are injected into the nozzle part, respectively, the nozzles containing the first spinning solution and the second spinning solution are alternately connected. The first spinning solution and the second spinning solution may be simultaneously spun onto the substrate. In addition, in the method of the present invention, the first nozzle unit and the second nozzle unit may be continuously and alternately radiated, and two or more nozzle units may be included.

In addition, in the present invention, at least 2 to 10 of the first nozzle unit and the second nozzle unit of the spinning apparatus may be repeatedly disposed. A first spinning solution and a second spinning solution may be injected into the first nozzle unit and the second nozzle unit, respectively.

In addition, the configuration of the first nozzle unit and the second nozzle unit may be properly adjusted according to the size of the substrate, and the number of nozzle units may be alternately and repeatedly installed.

In the spinning apparatus, the first nozzle part and the second nozzle part may have similar diameters of 0.1 μm to 3 mm.

In this way, the present invention can manufacture a nanofiber sheet composed of two types of fiber diameters by alternately configuring two or more nozzle parts.

In addition, according to the spinning method of the present invention, when two or more polymer solutions of different configurations are spun into a substrate, a nanofiber web can be formed, and a drying method for volatilizing the solvent used in the polymer solution and controlling moisture, e.g. For example, after a process such as hot air drying, bonding between nanofibers is induced by a calendering process, and nanofiber filters having different pore sizes and thicknesses are controlled can be manufactured in a sheet form.

Then, when the sheet is recovered using a winding roll, the nanofiber filter of interest herein may be provided in a rolled state.

Meanwhile, a generally well-known mesh or non-woven fabric may be used as a substrate used for spinning the two or more kinds of spinning solutions of the present invention, and for example, a cellulose-based substrate may be used. The cellulose-based substrate forms a microporous structure, so it has good dimensional stability at high temperatures, heat resistance, high crystallinity, and the like. Therefore, the present invention can manufacture a nanofiber filter without the use of a separate adhesive by spinning the above-described two types of spinning solutions on such a substrate so that nanofiber webs having two different diameters are formed. In this case, the cellulose-based substrate may be a regenerated cellulose substrate or a rayon-polyester-based synthetic fiber using an acrylic binder, but is not limited thereto.

On the other hand, Figure 1 shows a schematic diagram of the manufacturing process of a nanofiber filter according to an embodiment of the present invention.

1 is a method using a solution blowing spinning apparatus having two kinds of spinning solutions and two or more kinds of nozzle parts.

In FIG. 1, the first nozzle unit 10 and the second nozzle unit 20 may be repeatedly disposed, and the first and second nozzle units respectively contain the first spinning solution 30 and the second spinning solution ( 40) is alternately injected and then co-spun on the substrate 50, the first nanofibers 32 and the second nanofibers 42 having two diameters are entangled and evenly dispersed on the substrate A nanofiber sheet may be formed.

At this time, the substrate can be moved through a conveyor belt, and at the same time as the first and second spinning solutions are spun, a fan 70 is installed in the collecting unit to increase the collection rate of the nanofibers and at the same time solvent drying can proceed.

In addition, the first spinning solution and the second spinning solution may be put into the first spinning solution storage tank and the second spinning solution storage tank, respectively, and used for the nanofiber filter.

In addition, although not shown in the drawing, the first nozzle unit may be installed connected to the first spinning solution storage tank. Similarly, the second nozzle unit may be installed connected to the second spinning solution reservoir. The first nozzle part and the second nozzle part may have the same diameter within the aforementioned range of 0.1 μm to 3 mm.

Figure 2a schematically illustrates a manufacturing process diagram of a nanofiber filter according to another embodiment of the present invention.

2A shows an example of a side view of an electrospinning device or a melt blowing spinning device having two or more nozzle parts, and an electrospinning device may be preferably used. More specifically, FIG. 2A shows a side view of the electrospinning device, and FIG. 2B is a schematic perspective view of the spinning device used in FIG. 2A.

At this time, although the nozzle part of the spinning device is shown as one type in the side view of FIG. 2A, as shown in FIG. 2B, the nozzle part is in a state in which several nozzles are connected, including the first nozzle part 10 and the second nozzle part 20. It has been, and the first spinning solution and the second spinning solution are added to the nozzle unit, and a nanofiber sheet can be produced.

According to one embodiment, when the electrospinning device is used in the present invention, the electrospinning device includes two or more nozzle parts, and the first spinning solution and the second spinning solution are prepared with two types of polymer concentration or weight average molecular weight. After each injection into the nozzle unit, the first spinning solution and the second spinning solution may be simultaneously spun onto the substrate by alternately connecting the nozzles containing the first spinning solution and the second spinning solution. In addition, in the method of the present invention, the first nozzle unit and the second nozzle unit may be continuously and alternately radiated, and two or more nozzle units may be included.

Therefore, in the case of the electrospinning apparatus, referring to FIGS. 2A and 2B, the first nozzle unit 10 and the second nozzle unit 20 are alternately installed to provide the first spinning solution and the second spinning solution on the substrate 50. It is possible to manufacture a sheet by simultaneously spinning, which can be recovered using a winding roll (62). Through the above method, a nanofiber filter in which the first nanofibers 32 and the second nanofibers 42 having two types of diameters on the substrate are evenly dispersed can be formed.

On the other hand, according to another embodiment of the present invention, a substrate; and a first nanofiber and a second nanofiber having different diameters dispersed on the substrate.

The first nanofibers and the second nanofibers may be formed in a network form on a substrate and mixed and dispersed.

In addition, as described above, the first nanofiber is a fiber assembly having a diameter of 1 μm or less, and the second nanofiber is a fiber assembly having a diameter twice or more than the diameter of the first nanofiber, and the first nanofiber and The average pore diameter of the second nanofibers may be 0.1 to 10 μm.

The ratio of the first nanofiber and the second nanofiber is 1: 1 when calculated as the ratio of the number of nozzles for spinning each nanofiber assembly, the volume ratio of the spun spinning solution, or the weight ratio of the spun spinning solution. It may be greater than or equal to 1:1 to 1:30 or 1:1 to 1:5.

In addition, the diameter of the first nanofiber may be 10 nm to 1000 nm, and the diameter of the second nanofiber may be 0.8 μm to 3 μm.

Further, in the present invention, a fiber assembly including the first nanofibers and the second nanofibers formed by spinning on a substrate is defined as a "nanofibler", and the particles may be dust particles.

Therefore, the nanofiber filter of the present invention may have a structure including a substrate and a particle removal layer, and the particle removal layer is evenly dispersed on the substrate like a network as described above.

At this time, the surface density of the particle removal layer in the nanofiber filter of the present invention is preferably in the range of 1 g/m ² to 50 g/m ² .

In addition, in the present invention, the substrate and the particle removal layer may be formed in a structure that repeats each other, and the structure has an advantage of having a lower differential pressure than a conventional structure including only one type of nanofiber.

On the other hand, as described above, the first nanofiber and the second nanofiber can be prepared using a solution containing the same type of polymer having different concentrations or different weight average molecular weights.

The polymer may be at least one selected from the group consisting of polyvinylidene fluoride, polyacrylonitrile, polyethylene oxide, polyvinyl alcohol, polyvinyl chloride, and polyethylene terephthalate.

As described above, the present invention can produce a nanofiber filter having a large thickness compared to basis weight by reducing the density of the sheet by preparing a sheet having different fiber diameters using the two or more kinds of spinning solutions. In addition, it is possible to provide a nanofiber sheet advantageous to differential pressure by providing various pore sizes by configuring two types of fiber diameter. In addition, the present invention can provide a nanofiber sheet having a high dust collection capacity due to a low density and a large thickness. Such a sheet has improved dust collection efficiency and is effective for application as an air filter.

Hereinafter, the action and effect of the invention will be described in more detail through specific examples of the invention. However, this is presented as an example of the invention, and thereby the scope of the invention is not limited in any sense.

<Spinning conditions>

The spinning solution used in the manufacture of the nanofiber filter was prepared using PAN and DMF under the spinning conditions in Table 1 below.

polymer Solvent/TSC write note PAN (Mw 150,000) DMF/8,12 or 14 wt % Miracloth 20ml/h @ 30kV,
tip-to-collector 15cm

That is, the spinning solution is prepared by changing the concentration such as 8% by weight, 12% by weight or 14% by weight using PAN having the same Mw, to prepare a polymer solution and used in Examples 1 to 4 and Comparative Examples 1 to 8 did

In Examples 1 to 4, 8% by weight and 12% by weight or 8% by weight and 14% by weight of the polymer solution was selected and used as the first spinning solution and the second spinning solution.

In Comparative Examples 1 to 8, only one type of polymer solution of 8% by weight, 12% by weight or 14% by weight was used as a spinning solution.

Example 1

As shown in FIG. 2, the first spinning solution and the second spinning solution were respectively injected into the nozzle-type electrospinning apparatus in which the first nozzle unit and the second nozzle unit are alternately and repeatedly disposed.

*First spinning solution: polymer solution containing 8% by weight of PAN

*Second spinning solution: polymer solution containing 14 weight concentration of PAN

Then, the first spinning solution and the second spinning solution were simultaneously spun to prepare a nanofiber filter. In addition, the nanofiber filter was prepared in the form of a sheet and recovered using a winding roll.

Examples 2 to 4

A nanofiber filter was prepared in the same manner as in Example 1, except that the concentrations of the first and second spinning solutions were changed to the concentrations shown in Table 4.

Comparative Examples 1 to 2

One type of spinning solution was fixed at a concentration of 14% by weight and 8% by weight, injected into a nozzle-type spinning device, respectively, and one type of spinning solution was spun on a fiber substrate (miracloth) to prepare a nanofiber filter.

Comparative Examples 3 to 8

One type of spinning solution was fixed at the concentration shown in Table 4, each injected into a nozzle-type spinning device, and one type of spinning solution was spun on a fiber substrate (miracloth) to prepare a nanofiber filter.

Test Example 1

For Example 1 and Comparative Examples 1 and 2, pore size and porosity were comparatively analyzed through basis weight, density, thickness measurement, SEM analysis, and porometer measurement in the following manner. In addition, the efficiency and differential pressure of the sheet were measured and the results are shown in Table 3.

Specifically, the nanofiber filters prepared in Examples and Comparative Examples were sampled in three 4cmX4cm sizes. The weight of each sample was measured, and the basis weight was calculated through the average value.

In addition, the thickness of three samples at random locations was measured using a digital thickness gauge, and the average value was shown. Based on the measured thickness and basis weight, the density and porosity of the sample were calculated by applying the density of the spinning polymer used.

The size of the pores was measured using a capillary flow porometer from PMI (Porous Materials Inc), and after preparing the fabric to an appropriate size (3 cm × 3 cm), the surface tension was measured using a known Galwick solution.

In addition, FE-SEM images of Example 1 and Comparative Examples 1 and 2 are shown in FIGS. 3A to 5 . The pore size distribution with respect to the diameter of Example 1 and Comparative Example 2 was compared and shown in FIG. 6 .

Sample description Fiber diameter write
(substrate) Example 1 PAN 8wt%/14wt%
(Co-spindle) 350nm/1.65㎛ mira cloth Comparative Example 1 PAN 14wt% 1.65㎛ mira cloth Comparative Example 2 PAN 8wt% 350 nm mira cloth

Referring to Table 2 and FIGS. 3a and 3b, Example 1 shows the appearance of a fabric composed of a first nanofiber assembly having a diameter of 350 nm and a second nanofiber assembly having a diameter of 1.65 μm.

However, in FIG. 4, Comparative Example 1 showed the appearance of a fabric composed of only one type of 1.65 μm fiber aggregate. In addition, in FIG. 5, Comparative Example 2 showed the appearance of a fabric composed of only one type of 350 nm fiber aggregate.

In addition, as confirmed from the results of FIG. 6, since Example 1 uses two types of spinning solutions having different concentrations compared to Comparative Examples 1 and 2, it can be seen that the two types of nanofiber groups are evenly distributed on the substrate. can

basis weight (g/m ² ) thickness
(μm) Efficiency (%) Pressure drop
(mmAQ) Mean pore diameter
(μm) Example 1 3.111 14.5 92.5 5.3 2.5645 Comparative Example 1 3.000 17 3.94 0.2 not measurable Comparative Example 2 3.185 not measurable
(tenuity) 61.76 2.13 1.65

In addition, as shown in Table 3, Example 1 of the present invention exhibited excellent overall effects compared to Comparative Examples 1 and 2 having the same basis weight composed of only one type of fiber, and in particular, the dust collection efficiency increased rapidly.

On the other hand, Comparative Example 1 was composed of only nanofibers with a pore size of 1.65 μm, so the differential pressure was low and the thickness was thick, but the average pore measurement was not possible and the dust collection efficiency was particularly low at 3.94%. In addition, Comparative Example 2 was too thin to measure, and the efficiency was 61.76%, so it was not suitable for use as a filter.

Test Example 2

For Examples 2 to 4 and Comparative Examples 3 to 8, an experiment was conducted to confirm the effect of the ratio of the fiber aggregate when two types of nanofiber groups of the present application were included. Measurement of each physical property was performed in the same manner as in Test Example 1, and the results are shown in Table 4.

Fiber diameter write
(substrate) Example 2 PAN 8wt%/12wt% (1:2)
(Co-spindle) 350nm/800nm mira cloth Example 3 PAN 8wt%/12wt% (1:2)
(Co-spindle) 350nm/800nm mira cloth Example 4 PAN 8wt%/12wt% (1:2)
(Co-spindle) 350nm/800nm mira cloth Comparative Example 3 PAN 8wt% 350 nm mira cloth Comparative Example 4 PAN 12wt% 800 nm mira cloth Comparative Example 5 PAN 8wt% 350 nm mira cloth Comparative Example 6 PAN 12wt% 800 nm mira cloth Comparative Example 7 PAN 8wt% 350 nm mira cloth Comparative Example 8 PAN 12wt% 800 nm mira cloth

Referring to Table 4 and FIG. 7, Examples 2 to 4 all show the appearance of fabrics composed of a first nanofiber assembly having a diameter of 350 nm and a second nanofiber assembly having a diameter of 800 nm.

However, in FIG. 8, Comparative Examples 3, 5, and 7 showed fabrics composed of only one type of 350 μm fiber aggregate. In addition, in FIG. 9, Comparative Examples 4, 6, and 8 showed fabrics composed of only one type of 800 nm fiber aggregate.

In addition, as confirmed in the results of FIG. 10, Example 2 uses two types of spinning solutions having different concentrations compared to Comparative Examples 3 and 4 of the same basis weight, so that the two types of nanofiber groups are evenly distributed on the substrate. distribution can be seen. In addition, in FIG. 11, since Example 3 uses two types of spinning solutions having different concentrations compared to Comparative Examples 5 and 6 of the same basis weight, it can be seen that the two types of nanofiber groups are evenly distributed on the substrate. In addition, in Figure 12, since Example 4 uses two types of spinning solutions with different conditions compared to Comparative Examples 7 and 8 of the same basis weight, it can be seen that the two types of nanofiber groups are evenly distributed on the substrate.

basis weight
(g/m ² ) thickness
(μm) Efficiency
(%) Pressure drop
(mmAQ) Mean pore diameter
(μm) Example 2 18.146 17.3 77.29 3.5 2.7181 Example 3 20.708 37.3 95.38 7.4 2.1821 Example 4 21.104 40.2 98.99 11.1 1.786 Comparative Example 3 17.229 13.1 93.48 6.6 1.6532 Comparative Example 4 18.750 18.5 31.91 1.3 5.6788 Comparative Example 5 19.813 27.5 99.32 13.5 1.3575 Comparative Example 6 21.021 38 41.68 1.8 5.6275 Comparative Example 7 21.125 39 99.98 20 1.2149 Comparative Example 8 22.042 109.1 72.84 4.4 4.361

Referring to Table 5, in terms of the size of the pores measured by the porometer, Examples 2 to 4 of the present invention are different from Comparative Examples 3 to 8, and Comparative Examples 3, 5, and 7 composed of one type of fiber aggregate with a size of 350 nm Compared to Comparative Examples 4, 6, and 8 composed of one-type fiber aggregates with a size of 800 nm, the collection efficiency was very high. That is, in Examples 2 to 4, compared to Comparative Examples consisting of only one kind of nanofiber, the dust removal efficiency was increased because the differential pressure was low and various pore sizes were exhibited while the thickness increased.

On the other hand, Comparative Examples 3 to 8 have only one type of pore structure, so the dust collection efficiency is low even when the thickness is thick, or the dust collection efficiency is high due to the small pore size, but the differential pressure is very high and the thickness is too thin. ) was unfavorable.

10: first nozzle unit
20: second nozzle part
30: first spinning solution
32: first nanofiber
40: second spinning solution
42: second nanofiber
50: base
60, 62: winding roll
70: drying fan

Claims (14)

Two or more kinds of spinning solutions including polymers having different concentrations or different weight average molecular weights;
Using a spinning device having at least two first nozzle parts and a second nozzle part into which the two or more kinds of spinning solutions can be alternately injected,
Forming a sheet including first nanofibers and second nanofibers having different diameters on a substrate ; including ,
The diameter of the first nanofiber is 10 nm to 350 nm, the diameter of the second nanofiber is 0.8 μm to 3 μm,
The ratio of the first nanofiber and the second nanofiber is 1: 1 when calculated as the ratio of the number of nozzles for spinning each nanofiber assembly, the volume ratio of the spun spinning solution, or the weight ratio of the spun spinning solution. to 1:30 times,
Manufacturing method of nano fiber filter.
The method of claim 1, wherein the method
preparing a first spinning solution and a second spinning solution by dissolving polymers having different concentrations or different weight average molecular weights in a solvent;
alternately injecting the first spinning solution and the second spinning solution into at least two first nozzle parts and second nozzle parts; and
The first and second nanofibers having different diameters on the substrate by simultaneously spinning the first and second spinning solutions on the substrate through the first nozzle unit and the second nozzle unit of the spinning device. Forming a sheet including;
Method of manufacturing a nanofiber filter comprising a.
According to claim 2,
The second spinning solution is a method of manufacturing a nanofiber filter used by adjusting the concentration or weight average molecular weight of the polymer so that the difference is more than twice as large as the fiber diameter prepared using the first spinning solution.
According to claim 1,
The two or more kinds of spinning solutions include a first solution containing 1 to 20% by weight of a polymer having a weight average molecular weight of 100,000 to 4,000,000, and 10 to 30% by weight of a polymer having a weight average molecular weight of 100,000 to 4,000,000. A method for producing a nanofiber filter comprising a second solution.
delete delete According to claim 1,
The polymer is selected from the group consisting of fluorinated polyvinylidene, polyacrylonitrile, polyurethane, polyether sulfone, polyimide, polybutylene succinate, polyethylene oxide, polyvinyl alcohol, polyvinyl chloride and polyethylene terephthalate. Method for manufacturing one or more nanofiber filters.
According to claim 1,
The first nozzle part and the second nozzle part manufacturing method of a nanofiber filter in which at least 2 to 10 are repeatedly arranged.
According to claim 1,
The spinning device is a manufacturing method of a nanofiber filter comprising any one selected from the group consisting of an electrospinning device, a solution spinning device, a melt spinning device and a solution blowing spinning device having two or more nozzle parts.
write; and
A particle removal layer, which is a fiber aggregate including first nanofibers and second nanofibers having different diameters dispersed on the substrate,
The diameter of the first nanofiber is 10 nm to 350 nm, the diameter of the second nanofiber is 0.8 μm to 3 μm,
The ratio of the first nanofiber and the second nanofiber is 1: 1 when calculated as the ratio of the number of nozzles for spinning each nanofiber assembly, the volume ratio of the spun spinning solution, or the weight ratio of the spun spinning solution. to 1:30 times,
Nano fiber filter.
According to claim 10,
The substrate and the particle removal layer are formed in a structure that repeats each other,
The surface density of the particle removal layer is in the range of 1 g / m ² to 50 g / m ² Nanofiber filter.
delete According to claim 10,
The first nanofiber and the second nanofiber is a nanofiber filter formed using a solution containing the same type of polymer having different concentrations or different weight average molecular weights.
According to claim 13,
The polymer is selected from the group consisting of fluorinated polyvinylidene, polyacrylonitrile, polyurethane, polyether sulfone, polyimide, polybutylene succinate, polyethylene oxide, polyvinyl alcohol, polyvinyl chloride and polyethylene terephthalate. One or more nano-fiber filters.