Multilayer filter including cellulose layer and manufacturing method thereof

Abstract

The present invention relates to a multilayer filter including a cellulose layer and, more specifically, is characterized by comprising a filtering unit and a fiber support supporting the filtering unit, wherein the fiber support is manufactured to include a cellulose material extracted from waste. A method for manufacturing a multilayer filter including a cellulose layer according to one preferred embodiment of the present invention is characterized by comprising: an extraction step of extracting a cellulose material from waste; a manufacturing step of manufacturing the fiber support on the basis of the extracted cellulose material after the extraction step; and a fusion step of combining the filtering unit and the fiber support after the manufacturing step, wherein the bonding unit passing through the filtering unit and the fiber support is formed as the pressing unit ultrasonically heats the filtering unit and the fiber support while fusing same.

Description

Multilayer filter including cellulose layer and manufacturing method thereof

[0001] The present invention relates to a multilayer filter including a cellulose layer and a method for manufacturing the same, and more specifically, to a multilayer filter including a cellulose layer and a method for manufacturing the same, which extracts cellulose from discarded wood resources and manufactures a composite multilayer filter based on a cellulose support capable of blocking fine dust, bacteria, viruses, etc., thereby reducing the generation and replacement costs of air filter waste and enabling the recycling of wood resources.

[0002] Upcycling is generally considered a broader concept than recycling, which involves repairing and reusing discarded or unusable items. It goes beyond simply recycling previously discarded products and adds new value to them, reproducing them into completely different products. For example, Republic of Korea Patent Publication No. 10-2023-0077045 (June 1, 2023) discloses a waste textile upcycling system and its operational method.

[0003] Meanwhile, in the case of conventional discarded wood resources, they are being utilized as material resources (composting, feed, or recycling into panel boards) and as roadside pavement materials through shredded chips, but the ratio is not high, and most of them are simply incinerated and discarded, causing environmental problems such as carbon emissions due to incineration.

[0004] The present invention has been devised to solve the problems of the prior art as described above, and the purpose of the present invention is to provide a multilayer filter including a cellulose layer and a manufacturing method thereof, which can reduce the generation and replacement costs of air filter waste and enable recycling of wood resources by manufacturing a composite multilayer filter capable of blocking fine dust, bacteria, viruses, etc. based on a cellulose support by extracting cellulose from discarded wood resources.

[0005] The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems to be solved by the present invention that are not mentioned herein will be clearly understood by a person having ordinary skill in the technical field to which the present invention pertains from the description below.

[0006] A multilayer filter including a cellulose layer according to a preferred embodiment of the present invention comprises a filtering section and a fiber support supporting the filtering section, wherein the fiber support is manufactured including a cellulose material extracted from waste.

[0007] In addition, the filtering unit according to a preferred embodiment of the present invention includes a three-dimensional filtration layer, an electrostatic filtration layer laminated on the three-dimensional filtration layer, and a nanofiltration layer laminated on the electrostatic filtration layer, and the fiber support includes a surface layer laminated on top of the three-dimensional filtration layer and a support layer laminated on a lower portion of the nanofiltration layer, and the nanofiltration layer is provided between the electrostatic filtration layer and the support layer, so that deformation or damage of the nanofiltration layer is minimized.

[0008] In addition, the present invention further includes a pressing unit that combines the filtering unit and the fiber support by ultrasonic fusing according to a preferred embodiment of the present invention, and the filtering unit is characterized in that it is manufactured by including a thermoplastic resin.

[0009] In addition, the compression member according to a preferred embodiment of the present invention is characterized in that it forms an adhesive member that allows the filtering member and the fiber support to be joined as the thermoplastic resin melts when one side of the filtering member is heated.

[0010] In addition, in a method for manufacturing a multilayer filter including a cellulose layer according to a preferred embodiment of the present invention, the method includes an extraction step of extracting a cellulose material from waste, a manufacturing step of manufacturing the fibrous support based on the extracted cellulose material after the extraction step, and a fusion step of joining the filtering part and the fibrous support after the manufacturing step, wherein the pressing part is characterized in that the bonding part penetrating the filtering part and the fibrous support is formed by ultrasonically fusing and heating the filtering part and the fibrous support.

[0011] By the means for solving the above problem, the multilayer filter including a cellulose layer of the present invention and the manufacturing method thereof are effective in that the multilayer filter including a cellulose layer capable of blocking fine dust, bacteria, viruses, etc., is manufactured by extracting cellulose from discarded wood resources and using a cellulose support as a composite multilayer filter, thereby reducing the generation and replacement costs of air filter waste and providing a multilayer filter including a cellulose layer capable of recycling wood resources and a manufacturing method thereof.

[0012] In addition, the multilayer filter including the cellulose layer of the present invention and the manufacturing method thereof have the advantage of maximizing performance by reducing the lost flow area and improving the manufacturability of the material filter, such as bendability, by applying ultrasonic fusing technology and optimizing the ultrasonic fusing pattern in consideration of the low adhesiveness and other bonding properties of the nanofilter material in the nanofiltration layer.

[0013] In addition, the multilayer filter including the cellulose layer of the present invention and the manufacturing method thereof have the advantage of implementing the three main layers of a three-dimensional filtration layer, an electrostatic filtration layer, and a nanofiltration layer into a single filter, improving the durability of the multilayer filter through a surface layer and a support layer at the upper and lower portions, respectively, improving the efficiency of the filter by setting a main dust target for each layer, and enabling long-life use without being affected by moisture through a nanofilter of the final nanofiltration layer.

[0014] In addition, the multilayer filter including a cellulose layer of the present invention and the manufacturing method thereof have the advantage of being able to perform an upcycled cellulose-based fiber support that does not stick to each other even when heat energy is applied in a single process, by applying heat to a compression unit along both edges of the filtering unit while the fiber support is laminated on the filtering unit, thereby perforating the edges of the filtering unit and the fiber support, and filling the perforated space with a heated thermoplastic resin to form an adhesive unit and combine them, unlike conventional materials.

[0015] The effects of the present invention are not limited to the effects mentioned above, and effects of the present invention not mentioned herein will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0016] Figure 1 is a development diagram showing the configuration of a multilayer filter according to one embodiment of the present invention.

[0017] Figure 2 is a cross-sectional view showing the configuration of a multilayer filter according to one embodiment of the present invention.

[0018] Figure 3 (a) is an exemplary diagram showing the structure of a conventional single-layer filter, and Figure 3 (b) is an exemplary diagram showing the structure of a multi-layer filter according to an embodiment of the present invention.

[0019] Figure 4 is an exemplary diagram showing the configuration of a multilayer filter or a three-dimensional filter layer according to one embodiment of the present invention.

[0020] Figure 5 is a conceptual diagram showing the appearance of a multilayer filter before and after ultrasonic fusion according to one embodiment of the present invention.

[0021] Figure 6 is a diagram showing experimental data on dust collection efficiency and pressure drop by combined method.

[0022] Fig. 7 is an exemplary diagram showing a pattern of a compression part of a multilayer filter according to an embodiment of the present invention.

[0023] Figure 8 is a drawing showing the experimental results showing the pressure drop value according to the pattern of the compression part of the multilayer filter according to one embodiment of the present invention.

[0024] Figure 9 is a drawing comparing the performance of a multilayer filter according to an embodiment of the present invention and a conventional mass-produced filter.

[0025] FIG. 10 is a drawing showing a method for manufacturing a multilayer filter including a cellulose layer according to one embodiment of the present invention.

[0026] The terms used in this specification will be briefly explained, and the present invention will be described in detail.

[0027] The terms used in this invention have been selected from widely used, common terms, taking into account their functions. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Therefore, the terms used in this invention should be defined based on their meaning and the overall content of the invention, rather than simply their names.

[0028] When a part of a specification is said to “include” a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0029] Below, with reference to the attached drawings, embodiments of the present invention are described in detail so that those skilled in the art can easily implement them. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0030] Specific details, including the problems to be solved, means of solving them, and the effects of the invention, are included in the embodiments and drawings described below. The advantages and features of the present invention, and methods for achieving them, will become clearer with reference to the embodiments described below in detail, along with the accompanying drawings.

[0031] Hereinafter, the present invention will be described in more detail with reference to the attached drawings.

[0032] In a multilayer filter (1000) including a cellulose layer according to a preferred embodiment of the present invention, the filtering unit (10) and a fiber support (40) supporting the filtering unit (10) are included, and the fiber support (40) is manufactured including a cellulose material extracted from waste.

[0033] First, the fiber support (40) is prepared. The fiber support (40) has a fiber diameter in the range of 0.5 μm to 300 μm and a basis weight of 30 g / m. 2 130 g / m 2 , and may be a cellulose support having a thickness of 0.2 mm to 1.2 mm.

[0034] That is, the multilayer filter of the present invention is an air filter that laminates the fiber support (40) made of a cellulose fiber material obtained through upcycling. For example, the upcycled cellulose fiber is a component extracted from wood, paper, waste paper, etc., and the filtering unit (10) may be a thermoplastic filter such as PP (polypropylene), PE (polyethylene), PVdF (polyvinylidene fluoride), PES (polyether sulfone), or a filter having adsorption properties such as activated carbon in addition to PP (polyethylene). In addition, the air filter is bonded using heat such as thermal fusion / ultrasonic waves between the upcycled cellulose fiber support and the filter having thermoplastic properties such as PP (polypropylene), PE (polyethylene), PVdF (polyvinylidene fluoride), PES (polyether sulfone). And, the filtering member (10) having thermoplastic properties such as PP (polypropylene), PE (polyethylene), PVdF (polyvinylidene fluoride), and PES (polyether sulfone) can be formed to have a fiber diameter in the range of 0.05 μm to 10 μm. And, the thickness ratio of the fiber support (40) and the filtering member (10) having thermoplastic properties such as PP (polypropylene), PE (polyethylene), and PVdF (polyvinylidene fluoride) can be formed as 1 to 1.5 : 1 : 0.1 to 1.0 in the order of PP (polypropylene), PE (polyethylene), and PVdF (polyvinylidene fluoride).

[0035] In addition, the filtering unit (10) includes a three-dimensional filtration layer (100), an electrostatic filtration layer (200) laminated on the three-dimensional filtration layer (100), and a nanofiltration layer (300) laminated on the electrostatic filtration layer (200), and the fiber support (40) includes a surface layer (500) laminated on the upper portion of the three-dimensional filtration layer (100), and a support layer (400) laminated on the lower portion of the nanofiltration layer (300), and the nanofiltration layer (300) is provided between the electrostatic filtration layer (200) and the support layer (400) so as to minimize deformation or damage of the nanofiltration layer (300).

[0036] Here, the fiber diameter can be formed to gradually decrease so that smaller particles are sequentially filtered according to the flow of fluid in the order of the three-dimensional filtration layer (100), electrostatic filtration layer (200), and nano filtration layer (300).

[0037] First, the three-dimensional filter layer (100) is provided. The three-dimensional filter layer (100) may correspond to an outer skin and serves to capture coarse dust such as pollen and dust having a diameter of 10 μm or more. At this time, the three-dimensional filter layer (100) may be manufactured from a material having a relatively high strength compared to other layers, and the diameter of the filter fiber may be manufactured to be 10 μm or less, and may have a density of 50 g / m. 2 70g / m2 2 can be manufactured to have a weight of .

[0038] Next, the electrostatic filtration layer (200) is provided. The electrostatic filtration layer (200) can be laminated on the inner surface of the three-dimensional filtration layer (100) and serves to capture dust having a relatively small diameter. For example, the electrostatic filtration layer (200) serves to capture fine dust of PM10 to PM2.5. At this time, the electrostatic filtration layer (200) captures fine dust using electrostatic force as an electrostatic filter, and the diameter of the filter fiber can be manufactured to be about 0.5 μm to 5 μm, the dust collection efficiency can be 85% to 99.995%, and the pressure drop can be 0.5 mmAq to 7.0 mmAq.

[0039] And, the nanofiltration layer (300) is provided. The nanofiltration layer (300) can be laminated on the inner surface of the electrostatic filtration layer (200) and serves to capture dust having a very small diameter. For example, the nanofiltration layer (300) serves to capture ultrafine dust and viruses of PM2.5 or less. At this time, the nanofiltration layer (300) is a nanofilter and there is no decrease in performance and efficiency according to the use time and cycle, and the direct diameter of the filter fiber can be manufactured to be about 0.05 μm to 0.5 μm, the dust collection efficiency can be 85% to 99.995%, and the pressure drop can be about 1.5 mmAq.

[0040] In addition, it further includes a support layer (400) laminated on the inner surface of the nanofiltration layer (300). For example, the diameter of the filter fiber of the support layer (400) can be manufactured to be 10 μm or less, and 10 g / m 2 30g / m 2 can be manufactured to have a weight of .

[0041] At this time, the nanofiltration layer (300) is provided between the electrostatic filtration layer (200) and the support layer (400) to minimize deformation or damage of the nanofiltration layer (300). More specifically, the filter medium of the nanofiltration layer (300) is vulnerable to damage due to external impact and damage due to thermal changes, and thus, in order to minimize this, it is provided between the electrostatic filtration layer (200) and the support layer (400) which have relatively high strength.

[0042] Meanwhile, the fiber diameter of the fiber support (40) is within the range of 0.5 μm to 300 μm, the fiber diameter of the three-dimensional filtration layer (100) is within the range of 10 μm or less, the fiber diameter of the electrostatic filtration layer (200) is within the range of 0.5 μm to 5 μm, and the fiber diameter of the nano-filtration layer (300) is within the range of 0.5 μm or less.

[0043] If it is manufactured outside the above range, there is a problem that the ventilation amount decreases rapidly as the pressure loss increases rapidly compared to the dust collection efficiency, and when applied to a mask, there is a problem that breathing becomes difficult. In addition, there is a problem that the filtering efficiency for fine dust and ultrafine dust decreases, and when applied to a mask, there is a problem that moisture according to the user's exhalation is transferred to the electrostatic filter layer (200), and the dust collection efficiency of the electrostatic filter layer (200) is further reduced.

[0044] On the other hand, the thickness ratio of the three-dimensional filtration layer (100): electrostatic filtration layer (200): nano-filtration layer (300): support layer (400) is manufactured to be 1 to 1.5: 1: 0.1 to 0.2: 1. More specifically, the three-dimensional filtration layer (100) can be manufactured to have a thickness of 161 μm to 608 μm, the electrostatic filtration layer (200) can be manufactured to have a thickness of 161 μm to 483 μm, the nano-filtration layer (300) can be manufactured to have a thickness of 16 μm to 81 μm, and the support layer (400) can be manufactured to have a thickness of 135 μm to 483 μm.

[0045] At this time, if the thickness ratio of the three-dimensional filter layer (100): electrostatic filter layer (200): nano filter layer (300): support layer (400) is manufactured at a thickness ratio less than 1:1:0.1:1, there is a problem that the ventilation amount rapidly decreases as the pressure loss rapidly increases compared to the dust collection efficiency, and when applied to a mask, there is a problem that breathing becomes difficult. In addition, when the thickness ratio of the three-dimensional filter layer (100): electrostatic filter layer (200): nano-filter layer (300): support layer (400) is manufactured at a thickness ratio exceeding 1.5:1:0.2:1, there is a problem that the filtering efficiency for fine dust and ultrafine dust is reduced, and when applied to a mask, there is a problem that moisture according to the user's exhalation is transferred to the electrostatic filter layer (200), further reducing the dust collection efficiency of the electrostatic filter layer (200).

[0046] On the other hand, the three-dimensional filter layer (100) may be formed of multiple layers, for example, an upper layer (101), a middle layer (102), and a lower layer (103). At this time, referring to (a) of FIG. 3, when the outer layer is formed as a single layer as in the past, a clogging phenomenon may occur in which contaminants of various sizes in the air are blocked by large-diameter particles during the process of passing through the filter, and due to the shielding, even though the filter has a filtering ability, there is a problem in that the life of the filter is reduced as the differential pressure increases and the flow rate decreases, so that the filter can no longer perform its filtering function.

[0047] In contrast, referring to (b) of FIG. 3, the three-dimensional filter layer (100) applied to the multilayer filter including the cellulose layer of the present invention and the manufacturing method thereof is formed of the upper layer (101), the middle layer (102), and the lower layer (103), and the fiber diameter is gradually formed to be smaller so that smaller particles are sequentially filtered according to the flow of fluid in the order of the upper layer (101), the middle layer (102), and the lower layer (103), so that substances with large particles can be sequentially filtered from substances with small particles. Accordingly, the clogging phenomenon can be minimized, thereby facilitating the flow of air, increasing the filtering performance, and improving the life of the filter.

[0048] In addition, referring to FIG. 4, when a hole is created due to destruction or damage in the upper layer (101) and middle layer (102), the lower layer (103) performs filtering of air flowing through the hole, thereby minimizing the deterioration of filter performance due to damage compared to a conventional single layer.

[0049] Likewise, the multilayer filter including the cellulose layer of the present invention and the method for manufacturing the same have the advantage of being able to minimize the clogging phenomenon and minimizing the performance degradation of the filter due to damage by being laminated in a multilayer structure with the three-dimensional filtration layer (100), electrostatic filtration layer (200), nanofiltration layer (300) and support layer (400).

[0050] In addition, the multilayer filter including the cellulose layer of the present invention further includes a pressing part (600) that combines the filtering part (10) and the fiber support (40) by ultrasonic fusing, and the filtering part (10) is manufactured by including a thermoplastic resin. Here, the pressing part (600) forms an adhesive part (610) that allows the filtering part (10) and the fiber support (40) to be combined as the thermoplastic resin melts when one side of the filtering part (10) is heated.

[0051] More specifically, referring to FIG. 5, when the fiber support (40) is laminated on the filtering part (10), the pressing part (600) applies heat along both edges of the filtering part (10), so that the edges of the filtering part (10) and the fiber support (40) are perforated, and the perforated space is filled with a heated thermoplastic resin, thereby forming the bonding part (610). In other words, the filtering part (10) and the fiber support (40) are combined as the thermoplastic resin melted by the heat fills the perforated space. Unlike conventional materials, the cellulose-based fiber support extracted through upcycling does not stick to each other even when heat energy is applied, so that a hole is formed in the fiber support (40), and the thermoplastic resin melted by the heat from the filtering part (10) is filled in the hole and hardened, thereby combining the filtering part (10) and the fiber support (40). In this way, there is an advantage in that the process of forming a hole in the fiber support (40), melting a thermoplastic resin, and then filling the melted thermoplastic resin into the formed hole can be performed in a single process.

[0052] Meanwhile, when the cellulose layer and filter material are bonded together in a bonding manner, such as in the conventional hot melt method, a large amount of adhesive is required due to differences in the material, basis weight, and thickness of the support layer, and there is a problem that the performance of the filter is reduced due to a decrease in efficiency and an increase in differential pressure as a large amount is applied.

[0053] In contrast, referring to FIG. 6 and Tables 1, 2 and 3, the multilayer filter including the cellulose layer of the present invention has an electrostatic filtration layer and a nanofiltration layer, which are core filtration layers based on thermoplastic resins, attached between the cellulose supports using a medium that sinteres the cellulose supports to each other, in order to improve the parts where ultrasonic fusion between cellulose supports is impossible and the parts where lamination between cellulose and the filter is not easy, and thus has the advantage of reducing differential pressure and improving the efficiency of the filter.

[0054] Differential efficiency (%) Differential pressure (mmAq) Electrostatic filter layer 95,502.0 Nano filter layer 88.002.5

[0055] Separation efficiency (%) Differential pressure (mmAq) After ultrasonic bonding 99.005.1 After adhesive bonding 96.776.3

[0056] MethodCaseLaminationCombination efficiency(%)Differential pressure(mmAq)UltrasonicLaminationACellulose support-Electrostatic filter-Nanofilter-Cellulose support99.24.9BCellulose support-Electrostatic filter-Nanofilter-Thermal bond support99.35.3CCellulose support-Electrostatic filter-Nanofilter-Thermal bond support98.75.1DThermal bond support-Electrostatic filter-Nanofilter-Cellulose support98.95EThermal bond support-Electrostatic filter-Nanofilter-Cellulose support99.25.1AdhesiveLaminationACellulose support-Electrostatic filter-Nanofilter-Cellulose support99.26.3BCellulose support-Electrostatic filter-Nanofilter-Thermal bond Support 97.16.1C Cellulose Support - Electrostatic Filter - Nanofilter - Thermal Bond Support 96.86.3D Thermal Bond Support - Electrostatic Filter - Nanofilter - Cellulose Support 96.46.6E Thermal Bond Support - Electrostatic Filter - Nanofilter - Cellulose Support 97.36

[0057] Here, [Table 1] shows the core filter layer efficiency and differential pressure data, [Table 2] shows the efficiency and differential pressure data according to the bonding method, and [Table 3] is a diagram showing a comparative case of ultrasonic bonding and adhesive bonding. Specifically, in the case of the conventional adhesive bonding method, the differential pressure is about 6.3 mmAq and the filter efficiency is about 96.77%, and in the case of the ultrasonic bonding method applied to the multilayer filter of the present invention, the differential pressure is about 5.1 mmAq and the filter efficiency is about 99.00%, which can be seen to be higher in efficiency than the conventional adhesive bonding method.

[0058] Next, referring to FIG. 7, the pressing portion (600) is illustrated as the adhesive portion (610) that allows the three-dimensional filtration layer (100), the electrostatic filtration layer (200), the nanofiltration layer (300), and the support layer (400) to be joined together through ultrasonic pressing. The adhesive portions (610) are formed in a plurality of manners and penetrate the three-dimensional filtration layer (100), the electrostatic filtration layer (200), the nanofiltration layer (300), and the support layer (400) in that order by ultrasonic pressing, and contain an adhesive to allow the three-dimensional filtration layer (100), the electrostatic filtration layer (200), the nanofiltration layer (300), and the support layer (400) to be bonded together. At this time, the plurality of adhesive portions (610) may be formed in a grid shape that is arranged to be inclined at an angle. That is, the plurality of adhesive portions (610) are formed to have a circular cross-section with a smaller diameter compared to conventional adhesive portions (E1, E2, E3) formed by conventional ultrasonic pressing, and the plurality of adhesive portions (610) are arranged adjacent to each other to form a line.

[0059] More specifically, in order to set the pattern of the plurality of adhesive portions (610), in the TSI 8130 filter performance test, the dust simulation is paraffin oil or NaCl (0.3 μm or less), the flow rate is 32 LPM, and monodisperse particles of 0.3 μm are sprayed under general environmental conditions, and the dust collection efficiency before and after the filter is calculated by counting the number of particles before and after using a light scattering method. That is, after combining patterns of various shapes as in FIG. 7, and looking at the pressure drop analysis results as in FIG. 8, Pattern 1 and Pattern 4 have relatively low pressure drop values, but Pattern 1 has problems such as the layers separating due to relatively low adhesiveness of each layer, resulting in low manufacturability. Therefore, the plurality of adhesive portions (610) are formed in a grid shape that is arranged obliquely, so that the pressure drop value of the multilayer filter including the cellulose layer of the present invention and the manufacturing method thereof can be minimized.

[0060] The above three-dimensional filtration layer (100) can be manufactured to have a thickness of 161 μm to 608 μm, the above electrostatic filtration layer (200) can be manufactured to have a thickness of 161 μm to 483 μm, the above nanofiltration layer (300) can be manufactured to have a thickness of 16 μm to 81 μm, the above support layer (400) can be manufactured to have a thickness of 135 μm to 483 μm, the above three-dimensional filtration layer (100) has a fiber diameter in the range of 15 μm to 300 μm, the above electrostatic filtration layer (200) has a fiber diameter in the range of 0.5 μm to 5 μm, the above nanofiltration layer (300) has a fiber diameter in the range of 0.5 μm or less, and the above support layer (400) has a fiber diameter in the range of 15 μm to 300 μm. As it is manufactured to be included in the range of 300μm, the dust collection efficiency is 95.77%, and the plurality of adhesive parts (610) are formed in a grid shape that is arranged obliquely, so that there is an advantage of minimizing the pressure drop value of the multilayer filter including the cellulose layer of the present invention and the manufacturing method thereof. In other words, as a result of testing through the field test method of TSI 8130 (flow rate 32 LPM), it can be confirmed that the dust collection efficiency (sodium chloride) is 96.4% for the first time, 95.8% for the second time, and 95.1% for the third time, and the average dust collection efficiency is 95.77% or more.

[0061] In addition, in the above nanofiltration layer (300), by applying ultrasonic fusing technology and optimizing the ultrasonic fusing pattern in consideration of the low adhesiveness and other bonding properties of the nanofilter material, there is an advantage in that the lost flow area can be reduced to maximize performance and improve the manufacturability of the material filter, such as bendability.

[0062] In addition, the three main layers of the three-stage filtration layer (100), electrostatic filtration layer (200), and nano-filtration layer (300) are implemented as a single filter, the durability of the nano-filtration layer (300) is improved through the support layer (400), the efficiency of the filter is improved by setting the main dust target for each layer, and there is an advantage in that long-life use without being affected by moisture is possible through the nano-filter of the nano-filtration layer (300) at the last stage.

[0063] In addition, there is an advantage in that a high-efficiency / low-pressure differential long-life filter design is possible through various combinations by comparing the dust collection efficiency and pressure drop characteristics of the electrostatic filter and nano filter of the electrostatic filter layer (200) and nano filter layer (300). For example, an E10 grade (85%) MB filter + E10 grade (85%) nano filter = E11 grade filter (>95%) can be used.

[0064] And, referring to FIG. 9, the multilayer filter including the cellulose layer of the present invention can maintain the removal efficiency of ultrafine dust even when the use period is extended compared to a conventional general mass-produced filter. More specifically, the multilayer filter including the cellulose layer of the present invention has a lifespan of 12 months or more, which is 4 to 12 times longer than a conventional mass-produced filter. In other words, the multilayer filter including the cellulose layer of the present invention can drastically improve the lifespan of the filter compared to the conventional filter, and has the advantage of maintaining high-efficiency filtration performance.

[0065] Hereinafter, a method for manufacturing a multilayer filter including a cellulose layer according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0066] Referring to FIG. 10, in a method for manufacturing a multilayer filter including a cellulose layer according to a preferred embodiment of the present invention, the method includes an extraction step (S100) of extracting a cellulose material from waste, a manufacturing step (S200) of manufacturing the fibrous support (40) based on the extracted cellulose material after the extraction step (S100), and a fusion step (S300) of joining the filtering part (10) and the fibrous support (40) after the manufacturing step (S200), and the pressing part (600) ultrasonically fuses the filtering part (10) and the fibrous support (40) and heats them, thereby forming the bonding part (610) penetrating the filtering part (10) and the fibrous support (40).

[0067] More specifically, in a state where the fiber support (40) is laminated on the filtering part (10), the pressing part (600) applies heat along both edges of the filtering part (10), so that the edges of the filtering part (10) and the fiber support (40) are perforated, and the perforated space is filled with a heated thermoplastic resin, thereby forming the bonding part (610). In other words, the filtering part (10) and the fiber support (40) are combined as the thermoplastic resin melted by the heat fills the perforated space. Unlike conventional materials, the cellulose-based fiber support extracted through upcycling does not stick to each other even when heat energy is applied, so that a hole is formed in the fiber support (40), and the thermoplastic resin melted by the heat from the filtering part (10) is filled in the hole and hardened, thereby combining the filtering part (10) and the fiber support (40). In this way, there is an advantage in that the process of forming a hole in the fiber support (40), melting a thermoplastic resin, and then filling the melted thermoplastic resin into the formed hole can be performed simultaneously.

[0068] Most conventional mask and air purifier filters are melt-blown electrostatic filters that utilize electrostatic force to filter, resulting in high efficiency and low differential pressure. However, electrostatic filters are vulnerable to moisture, and their dust collection efficiency decreases over time due to durability. For example, the E11 Grade standard can decrease from 95% to as much as 30%, and the dust collection efficiency of electrostatic filters can decrease to 30% to 60% over time. Furthermore, among electrostatic filters, nanofilters with small filter fibers have a nano-sized fiber weave, and while the change in lifespan and decrease in efficiency due to filter use is minimal, they have the problem of having a differential pressure that is two to three times higher than that of electrostatic filters of the same efficiency grade. Furthermore, utilizing electrostatic filters without a decrease in lifespan requires components such as fans and motors, which rapidly increases the volume of the filtering system, resulting in space and noise issues.

[0069] The multilayer filter including the cellulose layer of the present invention and the method for manufacturing the same can complement the problems of conventional electrostatic filters and nanofilters and maximize efficiency and differential pressure performance.

[0070] The multilayer filter including the cellulose layer of the present invention and the method for manufacturing the same can be applied to, but are not limited to, home and commercial ventilation devices or air purification systems (ERV, DOAS), multi-use facility air conditioning systems and ventilation devices, semiconductor process and hospital (operating room) clean room systems, air purifiers, automobile air conditioner filters, etc.

[0071] By using the multilayer filter including the cellulose layer of the present invention and the method for manufacturing the same, a composite multilayer filter capable of blocking fine dust, bacteria, viruses, etc., based on a cellulose support, is manufactured by extracting cellulose from discarded wood resources, thereby reducing the generation and replacement costs of air filter waste and recycling wood resources.

[0072] In this way, it will be understood by those skilled in the art that the technical configuration of the present invention described above can be implemented in other specific forms without changing the technical idea or essential features of the present invention.

[0073] Therefore, the embodiments described above should be understood as being exemplary and not restrictive in all respects, and the scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

[0074] [Explanation of symbols]

[0075] 10: Filtering section

[0076] 100: 3D filtration layer

[0077] 101: Upper floor

[0078] 102: Middle layer

[0079] 103: Lower floor

[0080] 200: Electrostatic filtration layer

[0081] 300: Nanofiltration layer

[0082] 40: Fiber support

[0083] 400: Supporters

[0084] 500: Surface layer

[0085] 600: Compression part

[0086] 610: Adhesive

[0087] 1000: Multilayer filter

[0088] D: Dust

[0089] E1: Conventional adhesive

[0090] E2: Conventional adhesive

[0091] E3: Conventional adhesive

[0092] S100: Extraction stage

[0093] S200: Manufacturing Stage

[0094] S300: Fusion stage

Claims

1. Filtering section; and A fiber support supporting the above filtering unit; The above fiber support is, A multilayer filter comprising a cellulose layer characterized in that it is manufactured including a cellulose material extracted from waste.

2. In paragraph 1, The above filtering unit, three-dimensional filtration layer; An electrostatic filter layer laminated on the above three-dimensional filter layer; and A nanofiltration layer laminated on the above electrostatic filtration layer; The above fiber support is, A surface layer laminated on top of the three-dimensional filter layer; and It includes a support layer laminated on the lower part of the above nanofiltration layer; A multilayer filter including a cellulose layer, characterized in that the nanofiltration layer is provided between the electrostatic filtration layer and the support layer, so that deformation or damage of the nanofiltration layer is minimized.

3. In paragraph 1, It further includes a compression unit that combines the filter unit and the fiber support by ultrasonic fusing; A multilayer filter including a cellulose layer, characterized in that the filtering part is manufactured by including a thermoplastic resin.

4. In paragraph 3, The above compression part, A multilayer filter including a cellulose layer, characterized in that when one side of the filtering part is heated, the thermoplastic resin melts and forms an adhesive portion that allows the filtering part and the fiber support to be bonded together.

5. In the manufacturing method of a multilayer filter including the cellulose layer of paragraph 4, An extraction step for extracting cellulose material from waste; After the above extraction step, a manufacturing step of manufacturing the fiber support based on the extracted cellulose material; and After the above manufacturing step, a fusion step of combining the filtering part and the fiber support is included; A method for manufacturing a multilayer filter including a cellulose layer, characterized in that the pressing part forms the adhesive part penetrating the filtering part and the fiber support by ultrasonically fusing and heating the filtering part and the fiber support.

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