WO2021125157A1 - Fiber aggregate - Google Patents

Fiber aggregate Download PDF

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Publication number
WO2021125157A1
WO2021125157A1 PCT/JP2020/046707 JP2020046707W WO2021125157A1 WO 2021125157 A1 WO2021125157 A1 WO 2021125157A1 JP 2020046707 W JP2020046707 W JP 2020046707W WO 2021125157 A1 WO2021125157 A1 WO 2021125157A1
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WIPO (PCT)
Prior art keywords
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fiber
fiber aggregate
fibers
air
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PCT/JP2020/046707
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French (fr)
Japanese (ja)
Inventor
信一 垰口
竜大 尾下
Original Assignee
ヤマシンフィルタ株式会社
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Application filed by ヤマシンフィルタ株式会社 filed Critical ヤマシンフィルタ株式会社
Priority to CN202080085304.6A priority Critical patent/CN114867896B/en
Publication of WO2021125157A1 publication Critical patent/WO2021125157A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
    • B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
    • B32B5/26—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer another layer next to it also being fibrous or filamentary
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
    • D04H3/016—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the fineness

Definitions

  • the present invention relates to a fiber aggregate.
  • Non-woven fabrics are used in various applications such as filter media for air filters, filter media for oil filters, oil absorbents, sound absorbing materials, shock absorbing materials, heat insulating materials, and heat insulating materials.
  • Patent Document 1 describes ultrafine fibers A having a fiber diameter D of 100 to 1000 nm and the ultrafine fibers A for the purpose of providing a non-woven fabric and a bag filter filter medium having excellent pleating performance as well as collection performance.
  • a non-woven fabric containing a fiber B having a fiber diameter larger than that of the fiber A and having a Gale-type rigidity and softness of 2000 mgf or more is described.
  • Patent Document 2 describes an air filter filter medium mainly made of glass fiber for the purpose of providing an air filter filter medium that consumes less energy, has high efficiency, and has a low pressure loss.
  • the fibers contain chopped strand glass fibers and ultrafine glass fibers, and the cumulative frequency in the range of more than 1.5 ⁇ m and 2.9 ⁇ m or less in the fiber diameter distribution of the air filter filter medium is 2 to 15%.
  • a filter medium for an air filter, which is characterized by the above, is described.
  • An object of the present invention is to provide a fiber aggregate which is particularly useful as a filter medium for an air filter.
  • the present invention relates to the following ⁇ 1> to ⁇ 11>.
  • the average fiber diameter of the fibers constituting the fiber aggregate is 600 nm or more and 1500 nm or less, the content of the fibers having a fiber diameter of 1 ⁇ m or more and less than 2 ⁇ m is 10% or more and 50% or less, and the fibers constituting the fiber aggregate.
  • a fiber aggregate containing a thermoplastic resin as a main component is a thermoplastic resin as a main component.
  • ⁇ 2> The fiber aggregate according to ⁇ 1>, which contains 35% or more of fibers having a fiber diameter of 400 nm or more and less than 1000 nm.
  • ⁇ 3> The fiber aggregate according to ⁇ 1> or ⁇ 2>, wherein the content of fibers having a fiber diameter of 2 ⁇ m or more is 20% or less.
  • ⁇ 4> The fiber aggregate according to any one of ⁇ 1> to ⁇ 3>, wherein the content of fibers having a fiber diameter of 400 nm or more and less than 600 nm is 5% or more and 40% or less.
  • ⁇ 5> The fiber aggregate according to any one of ⁇ 1> to ⁇ 4>, wherein the content of fibers having a fiber diameter of 600 nm or more and less than 800 nm is 5% or more and 40% or less.
  • ⁇ 6> The fiber aggregate according to any one of ⁇ 1> to ⁇ 5>, wherein the content of fibers having a fiber diameter of 800 nm or more and less than 1000 nm is 5% or more and 40% or less.
  • ⁇ 7> The fiber aggregate according to any one of ⁇ 1> to ⁇ 6>, wherein the content of fibers having a fiber diameter of less than 400 nm is 20% or less.
  • thermoplastic resin is at least one selected from a polyolefin resin and a polyester resin.
  • thermoplastic resin is at least one selected from polypropylene and polybutylene terephthalate.
  • CV value of the basis weight of the fiber aggregate is 20% or less.
  • FIG. 1 is a schematic view showing an outline of the melt blow device 1.
  • the average fiber diameter of the fibers constituting the fiber aggregate is 600 nm or more and 1500 nm or less, the content of fibers having a fiber diameter of 1 ⁇ m or more and less than 2 ⁇ m is 10% or more and 50% or less, and the fiber assembly
  • the fibers that make up the body contain thermoplastic resin as the main component. According to the present invention, a fiber aggregate which has a low pressure loss and a high collection rate and is useful as a filter medium for an air filter can be obtained. Although the detailed reason why the above effects are obtained is unknown, some of them are considered as follows.
  • the present invention has found that by setting the average fiber diameter and the fiber diameter distribution of the fiber diameters constituting the fiber aggregate within a specific range, the fiber aggregate becomes particularly useful as a filter medium for an air filter.
  • the present invention will be described in more detail.
  • the average fiber diameter of the fibers constituting the fiber aggregate of the present invention is 600 nm or more and 1500 nm or less. When the average fiber diameter of the fibers constituting the fiber aggregate is within the above range, low pressure loss and high collection rate are obtained.
  • the average fiber diameter is preferably 700 nm or more, more preferably 800 nm or more, further preferably 900 nm or more, and preferably 1450 nm or less, more preferably 1400 nm or less, from the viewpoint of lower pressure loss and high collection rate. , More preferably 1300 nm or less.
  • the average fiber diameter of the fibers constituting the fiber aggregate is measured by the method described in Examples.
  • the content of fibers having a fiber diameter of 1 ⁇ m or more and less than 2 ⁇ m is 10% or more and 50% or less.
  • the content of the fibers having a fiber diameter of 1 ⁇ m or more and less than 2 ⁇ m is preferably 15% or more, more preferably 18% or more, further preferably 20% or more, and preferably 47% or less, more preferably 45% or less. , More preferably 42% or less.
  • the content of fibers having a fiber diameter of 1 ⁇ m or more and less than 2 ⁇ m is measured by the method described in Examples.
  • the content of the fiber having a fiber diameter of 400 nm or more and less than 1000 nm is preferably 35% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 36% or more, more preferably 38% or more, and preferably 90% or less, more preferably 85% or less, still more preferably 75% or less.
  • the content of fibers having a fiber diameter of 400 nm or more and less than 1000 nm is measured by the method described in Examples.
  • the content of the fiber having a fiber diameter of 2 ⁇ m or more is preferably 20% or less, more preferably 18% or less from the viewpoint of obtaining a fiber aggregate having a high collection rate. , More preferably 16% or less.
  • the content of fibers having a fiber diameter of 2 ⁇ m or more is measured by the method described in Examples.
  • the content of the fiber having a fiber diameter of 400 nm or more and less than 600 nm is preferably 5% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. And preferably 40% or less, more preferably 30% or less, still more preferably 25% or less.
  • the content of fibers having a fiber diameter of 400 nm or more and less than 600 nm is measured by the method described in Examples.
  • the content of the fiber having a fiber diameter of 600 nm or more and less than 800 nm is preferably 5% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 8% or more, more preferably 10% or more, and preferably 40% or less, more preferably 35% or less, still more preferably 30% or less.
  • the content of the fiber width having a fiber diameter of 600 nm or more and less than 800 nm is measured by the method described in Examples.
  • the content of the fiber having a fiber diameter of 800 nm or more and less than 1000 nm is preferably 5% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 6% or more, more preferably 8% or more, and preferably 40% or less, more preferably 35% or less, still more preferably 30% or less.
  • the content of the fiber width having a fiber diameter of 800 nm or more and less than 1000 nm is measured by the method described in Examples.
  • the content of the fiber having a fiber diameter of less than 400 nm is preferably 20% or less from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate, and more. It is preferably 18% or less, more preferably 15% or less. Further, the lower limit thereof is not particularly limited and may be 0%.
  • the content of fiber widths with a fiber diameter of less than 400 nm is measured by the method described in the Examples.
  • the geometric standard deviation of the fiber diameter of the entire fiber constituting the fiber aggregate of the present invention is preferably 3.0 ⁇ m or less, more preferably 2.6 ⁇ m or less, from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is more preferably 2.2 ⁇ m or less, and preferably 0.5 ⁇ m or more, more preferably 0.8 ⁇ m or more, still more preferably 1.0 ⁇ m or more.
  • a fiber aggregate in which the geometric standard deviation of the fiber diameter of the entire fiber is in the above range is preferable because it is excellent in in-plane uniformity.
  • the geometric standard deviation of the fiber diameter of the fiber having a fiber diameter of less than 1 ⁇ m (less than 1000 nm) is preferable from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate.
  • the geometric standard deviation of the fiber diameter of the fiber having a fiber diameter of 1 ⁇ m or more is preferably 3.0 ⁇ m from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate.
  • it is more preferably 2.0 ⁇ m or less, still more preferably 1.5 ⁇ m or less, and from the viewpoint of ease of production, it is preferably 0.1 ⁇ m or more, more preferably 0.3 ⁇ m or more, still more preferably 0.5 ⁇ m. That is all.
  • the fibers constituting the fiber aggregate of the present invention preferably have the above-mentioned fiber diameter distribution, but the case where the large diameter fiber and the small diameter fiber are not mixed and used but have a wide distribution. Depending on the case, an aggregate of fibers having two or more peaks is preferable from the viewpoint of ease of production and in-plane uniformity.
  • the fibers constituting the fiber aggregate of the present invention contain a thermoplastic resin as a main component.
  • the fiber aggregate of the present invention is preferably produced by the melt blow method as described later, and a thermoplastic resin is suitable as the fiber raw material.
  • the thermoplastic resin include polyolefin resins such as polyethylene (PE) and polypropylene (PP); polyester resins such as polybutylene terephthalate (PBT) and polyethylene terephthalate (PET); polyamide resins (PA) and the like.
  • thermoplastic resin is preferably at least one selected from a polyolefin resin and a polyester resin, more preferably at least one selected from polypropylene and polybutylene terephthalate, and further preferably polypropylene. ..
  • the thermoplastic resin may be used alone or in combination of two or more.
  • the fibers constituting the fiber assembly of the present invention contain 50% by mass or more of a thermoplastic resin, preferably 70% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and 100. It is not more than% by mass and may be 100% by mass.
  • the fiber aggregate may contain other components in addition to the above-mentioned thermoplastic resin.
  • Other components include surfactants, colorants, phosphorus-based and phenol-based antioxidants, benzotriazole-based weather-resistant stabilizers, hindered amine-based light-resistant stabilizers, blocking inhibitors, and dispersion of calcium stearate.
  • examples include agents, lubricants, nucleating agents, pigments, softeners, hydrophilic agents, water repellents, auxiliaries, water repellents, fillers, antibacterial agents, pesticides, insect repellents, chemicals, natural oils, synthetic oils and the like.
  • the fiber aggregate of the present invention is not particularly limited as long as the above-mentioned average fiber diameter and fiber diameter distribution can be obtained, and may be produced by a dry method or a wet method, but the above-mentioned average fiber diameter and fiber may be produced.
  • the method for manufacturing a dry fiber aggregate include a melt blow method and a spunbond method.
  • it is preferable to manufacture by the melt blow method and it is more preferable to manufacture by the melt blow method in which the thermoplastic resin is melted, discharged from the nozzle of the extruder, and ejected by a high-speed high-temperature air flow.
  • the molten thermoplastic resin is discharged from above to below, and high temperature and high pressure air is blown from the air nozzle toward the discharged thermoplastic resin from a substantially horizontal direction. It is preferable to use the molten thermoplastic resin as a fibrous resin and collect the fibrous resin to produce a fiber aggregate.
  • the molten thermoplastic resin is stretched by the air blown from the air nozzle to become a fibrous resin.
  • the longer the distance to collection the lower the density of fiber aggregates tends to be obtained.
  • FIG. 1 is a schematic view showing an outline of the melt blow device 1.
  • the melt blow device 1 mainly includes a resin supply unit 10, an air flow generation unit 20, a collection unit 30, and a superheated steam supply unit 40.
  • the resin supply unit 10 mainly includes a hopper 11, an extruder 12, a die 13, and a resin nozzle 14.
  • the raw material chip of the thermoplastic resin is put into the hopper 11 and heated by a heater (not shown) provided in the extruder 12 to melt the thermoplastic resin to obtain the melted thermoplastic resin.
  • the extruder 12 pushes the molten thermoplastic resin into the die 13 by a gear pump (not shown).
  • the resin nozzle 14 is provided on the die 13 and discharges the molten thermoplastic resin. From the resin nozzle 14, the molten thermoplastic resin is discharged from the upper side to the lower side.
  • the air flow generating unit 20 mainly includes a compressor 21 that generates compressed air, a pipe 22 through which compressed air passes, a regulator 23, a heater 24 that heats the pipe 22, and an air nozzle 25.
  • the compressor 21, the pipe 22, and the heater 24 correspond to a high-temperature and high-pressure air generating unit that generates high-temperature and high-pressure air.
  • the air nozzle 25 is provided adjacent to the resin nozzle 14, and discharges high-temperature and high-pressure air generated by the high-temperature and high-pressure air generation unit.
  • the temperature of the air discharged from the air nozzle 25 may be appropriately selected depending on the type of the thermoplastic resin and the like, but from the viewpoint of obtaining a desired average fiber diameter and fiber diameter distribution, it is preferably 400 ° C.
  • the resin nozzles 14 and the air nozzles 25 are provided side by side in a row toward the back of the paper in the figure, and the arrangement direction of the air nozzles 25 is substantially parallel to the arrangement direction of the resin nozzles 14, and the air nozzles 25 are arranged.
  • the region includes an arrangement region of the resin nozzle 14.
  • High temperature and high pressure air is discharged from the air nozzle 25 in a substantially horizontal direction.
  • the flow rate of the air discharged from the air nozzle 25 is preferably 5 L / min or more, more preferably 10 L / min or more, still more preferably 15 L / min or more, from the viewpoint of obtaining a desired average fiber diameter and fiber diameter distribution. Then, it is preferably 60 L / min or less, more preferably 45 L / min or less, and further preferably 35 L / min or less.
  • the collecting portion 30 is mainly a suction drum 31 having a substantially cylindrical shape for collecting fibrous resin, a blower 32, a suction portion 33 connected to the blower 32, and a non-woven fabric around which the non-woven fabrics 51 and 52 are wound. It has rolls 34 and 35 and a take-up drum 36.
  • the non-woven fabric 51 is a base material
  • the non-woven fabric 52 is a covering material (cover material).
  • the molten polymer discharged from the resin nozzle 14 becomes fine fibers (for example, nanofibers) and is sprayed onto the suction drum 31.
  • the non-woven fabric 51 drawn from the non-woven fabric roll 34 is wound around the suction drum 31, and the fibrous resin is adsorbed on the surface of the non-woven fabric 51 by sucking air from the suction unit 33.
  • the end of the non-woven fabric 51 is provided on the take-up drum 36. As the take-up drum 36 rotates at a constant speed, the non-woven fabric 51 on which the fibrous resin is adsorbed on the surface moves toward the take-up drum 36 at a constant speed.
  • the non-woven fabric 52 drawn from the non-woven fabric roll 35 is also provided at the end of the take-up drum 36. Therefore, when the take-up drum 36 rotates at a constant speed, the non-woven fabric 52 covers the fiber layer on the surface of the non-woven fabric 51. Then, by integrating the non-woven fabric 52 covering the fiber layer on the surface of the non-woven fabric 51 by calendar processing or the like, a structure in which the fiber aggregate is sandwiched between the non-woven fabrics 51 and 52 is obtained, which is the take-up drum 36. It is wound around.
  • the base material and the coating material are not essential constituent requirements, and the fiber aggregate means a portion in which the resin discharged from the resin nozzle 14 is laminated as a fibrous resin. Therefore, the fiber aggregate of the present invention may be used in a form sandwiched between the base material and the covering material, or only the fiber aggregate may be used.
  • the superheated steam supply unit 40 supplies superheated steam to the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31.
  • the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31 is a region where the air blown from the air nozzle 25 fibrates the molten thermoplastic resin.
  • the superheated steam supply unit 40 mainly includes a heater 41 for generating superheated steam, a pipe 42, and a superheated steam nozzle 43.
  • the heater 41 further heats saturated steam generated by a boiler or the like (not shown) to generate superheated steam at a high temperature.
  • the superheated steam is dry steam having a temperature higher than the boiling point, and is used, for example, in a temperature range of 200 ° C.
  • the superheated steam generated by the heater 41 is supplied to the superheated steam nozzle 43 via the pipe 42, and is discharged from the superheated steam nozzle 43.
  • the superheated steam nozzles 43 are provided side by side in a row toward the back of the paper surface, and the arrangement direction of the superheated steam nozzles 43 is substantially parallel to the arrangement direction of the resin nozzle 14 and the air nozzle 25.
  • the arrangement area includes the arrangement area of the resin nozzle 14 and the air nozzle 25.
  • the central axis of the resin nozzle 14 is substantially in the vertical direction. Therefore, the molten thermoplastic resin discharged from the resin nozzle 14 falls vertically downward under its own weight. Further, the central axis of the air nozzle 25 is substantially horizontal. Therefore, the high temperature and high pressure air is blown out from the air nozzle 25 in the horizontal direction.
  • the air nozzle 25 preferably intersects the central axis of the resin nozzle 14. That is, the tip of the air nozzle 25 is preferably located in front of the central axis of the resin nozzle 14.
  • the superheated steam nozzle 43 preferably has a central axis tilted in the horizontal direction, and discharges superheated steam toward the air nozzle 25 from below and behind the air nozzle 25.
  • the superheated steam discharged from the superheated nozzle 43 flows horizontally along with the accompanying flow, and is supplied to the atmosphere surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31.
  • the superheated steam By placing the superheated steam on the accompanying flow, the superheated steam easily spreads in the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31. Since the superheated steam is supplied to the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31, the molten thermoplastic resin discharged from the resin nozzle 14 is stretched in a high temperature atmosphere and becomes fibrous. Become.
  • the texture (basis weight) of the fiber aggregate is preferably 10 g / m 2 or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 15 g / m 2 or more, more preferably 20 g / m 2 or more, even more preferably 25 g / m 2 or more, and preferably 50 g / m 2 or less, more preferably 40 g / m 2 or less, even more preferably. Is 35 g / m 2 or less.
  • the fiber aggregate of the present invention is also characterized in that it is excellent in in-plane uniformity, and the CV value of the basis weight is preferably 20% or less, more preferably 16% or less, still more preferably 12% or less, and From the viewpoint of ease of production, it is preferably 0.5% or more, more preferably 1% or more, still more preferably 2% or more.
  • the basis weight and CV value of the fiber aggregate are measured by the method described in Examples.
  • the thickness of the fiber aggregate of the present invention may be appropriately selected depending on the intended use, but when the fiber aggregate is used for an air filter application, the thickness of the fiber aggregate is preferably selected from the viewpoint of improving the collection rate. It is 30 ⁇ m or more, more preferably 45 ⁇ m or more, further preferably 60 ⁇ m or more, still more preferably 85 ⁇ m or more, still more preferably 100 ⁇ m or more, and from the viewpoint of reducing pressure loss, it is preferably 500 ⁇ m or less, more preferably 400 ⁇ m or less. It is more preferably 300 ⁇ m or less, still more preferably 240 ⁇ m or less, and even more preferably 180 ⁇ m or less.
  • the thickness of the fiber aggregate is measured by, for example, a thickness gauge manufactured by Mitutoyo Co., Ltd.
  • the thickness of the fiber aggregate may be appropriately changed according to the intended use, and in the case of a thicker fiber aggregate, the thickness may be measured by setting a ruler on the side surface and measuring the natural thickness.
  • the collection rate (collection efficiency) of particles having a diameter of 0.3 ⁇ m at a permeation wind speed of 5.3 cm / sec is preferably 55% or more, more preferably 55% or more. It is 57% or more, more preferably 60% or more.
  • the collection rate is measured by removing static electricity from the filter medium for an air filter to eliminate the effect of collecting particles due to static electricity. It has excellent collection performance by forming a fiber aggregate having a specific average fiber diameter and a distribution of fiber diameters. The collection rate is measured by the method described in Examples.
  • the pressure loss is preferably low, and the pressure loss when the permeation air velocity is 5.3 cm / sec is preferably 40 Pa or less, more preferably 35 Pa or less. , More preferably 32 Pa or less.
  • the pressure loss is measured by the method described in the examples.
  • PF value is a value indicating the balance between the collection rate and the pressure loss, and is generally used as an index indicating the performance of the filter medium for an air filter, and is represented by the following formula (1).
  • PF value (1 / kPa) -Log 10 ⁇ (100-collection rate (%)) / 100 ⁇ / (pressure loss (Pa) / 1000) (1)
  • the fiber aggregate of the present invention When the fiber aggregate of the present invention is used as a filter medium for an air filter, the PF obtained from the collection rate of particles having a diameter of 0.3 ⁇ m at a permeation wind speed of 5.3 m / sec and the pressure loss at a permeation wind speed of 5.3 m / sec.
  • the value (1 / kPa) is preferably 10 or more, more preferably 15 or more, still more preferably 18 or more.
  • the fiber aggregate of the present invention is useful as a filter medium for an air filter, but is not limited to this, and is not limited to the filter medium for an oil filter, an oil absorbing material, a heat insulating material, a heat storage material, a heat insulating material, and a sound absorbing material. It is expected to be applied to materials.
  • the fiber aggregate of the present invention may have a lower layer (base material) and an upper layer (coating material) thereof, and may be laminated with other layers to form a filter medium for an air filter or the like. It can be applied to applications.
  • the central portion (about 40 to 60 cm from the end) of the fiber aggregate having a width of about 1 m when divided into five in the width direction was used as a sample.
  • -Average fiber diameter calculation method- (1) The measured values were classified into the following classes, and the relative frequency was calculated. Less than 200nm, 200nm or more and less than 400nm, 400nm or more and less than 600nm, 600nm or more and less than 800nm, 800nm or more and less than 1,000nm, 1 ⁇ m or more and less than 2 ⁇ m, 2 ⁇ m or more and less than 3 ⁇ m, 3 ⁇ m or more and less than 5 ⁇ m
  • the class values for each class are as follows.
  • Class value 200 nm 200 nm or more and less than 400 nm; class value 300 nm 400 nm or more and less than 600 nm; class value 550 nm 600 nm or more and less than 800 nm; class value 750 nm 800 nm or more 1,000 nm; class value 850 nm 1 ⁇ m or more and less than 2 ⁇ m; class value 1,500 nm 2 ⁇ m or more and less than 3 ⁇ m; class value 2,500 nm 3 ⁇ m or more and less than 5 ⁇ m; class value 4,000 nm 5 ⁇ m or more and less than 10 ⁇ m; class value 7,500 nm 10 ⁇ m or more; class value 10,000 nm (3) The logarithmic mean value of the measured fiber diameter was taken as the average fiber diameter.
  • ⁇ Thickness> The thickness of the fiber aggregate and the non-woven fabric used as the base material and the coating material was measured using a thickness gauge (547-301) manufactured by Mitutoyo Co., Ltd.
  • a fiber aggregate having a width of about 1 m was divided into five in the width direction, and measurements were performed for each to obtain an average value.
  • the basis weight was a value obtained by measuring a sample cut into 10 cm squares with a precision balance and dividing the mass (g) by the area (0.01 m 2).
  • the CV value was calculated together with the average value.
  • CV value (%) (standard deviation of basis weight distribution / average basis weight) x 100
  • the basis weight of the air filter filter medium laminated in the order of the base material, the fiber aggregate, and the coating material was measured, and the basis weight of the base material and the coating material was subtracted to obtain the basis weight of the fiber aggregate.
  • the CV value was calculated for the basis weight of the fiber aggregate.
  • a measurement sample of a filter medium for an air filter which is laminated in the order of a base material, a fiber aggregate, and a coating material, is set in a filter holder having an inner diameter of 113 mm (effective filter medium area 100 cm 2 ), and the filter medium permeation air velocity is 5.3 cm. It was adjusted with a flow meter so that it would be / sec. Then, the pressure loss generated upstream and downstream of the sample filter medium at this time was measured with a manometer. The air filter filter medium, which is the measurement sample, was subjected to static elimination treatment in advance, and then the pressure loss was measured.
  • the static elimination of the filter medium for the air filter complies with JIS B 9908: 2011 "Performance test method for air filter unit for ventilation and electrostatic precipitator for ventilation", 5.2.3.3d) 2) IPA saturated steam exposure method. I went. Further, the base material and the covering material are formed of a coarse non-woven fabric, and have almost no effect on the pressure loss.
  • the results are shown in Table 1 below.
  • the collection efficiency was 60% or more
  • the pressure loss (pressure loss) was 32 Pa or less
  • the PF value was 15.0 or more. ..
  • Comparative Example 2 in which the content of fibers of 1 ⁇ m or more and less than 2 ⁇ m was 50% or more, a sufficient collection rate (collection efficiency) could not be obtained.
  • Comparative Example 3 in which the average fiber diameter is less than 600 nm, the pressure loss is large because there are many fine fibers.
  • Comparative Example 4 in which the content of fibers of 1 ⁇ m or more and less than 2 ⁇ m was less than 10% and the average fiber diameter was relatively small, the pressure loss was high and a sufficient PF value could not be obtained.
  • the fiber aggregate of the present invention is suitably used as a filter medium for an air filter, and is used for various non-woven fabrics such as a filter medium for an air filter, for example, a filter medium for an oil filter, an oil absorbing material, a sound absorbing material, a heat insulating material, and a heat insulating material. It is expected to be applied to such applications.

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Nonwoven Fabrics (AREA)
  • Filtering Materials (AREA)
  • Laminated Bodies (AREA)

Abstract

Provided is a fiber aggregate particularly useful as a filter medium for an air filter.　In the fiber aggregate, the average fiber diameter of fibers constituting the fiber aggregate is 600-1500 nm, the content of fibers having a fiber diameter of greater than or equal to 1 μm but less than 2 μm is 10-50%, and the fibers constituting the fiber aggregate contain a thermoplastic resin as a main component.

Description

繊維集合体Fiber assembly
　本発明は、繊維集合体に関する。 The present invention relates to a fiber aggregate.
　現在、不織布はエアフィルタの濾材、オイルフィルタ用濾材、吸油剤、吸音材、衝撃吸収材、断熱材、保温材等の種々の用途に使用されている。
　例えば、特許文献１には、捕集性能だけでなく、プリーツ加工性にも優れた不織布及びバグフィルター濾材を提供することを目的として、繊維径Ｄが１００～１０００ｎｍの極細繊維Ａと、該極細繊維Ａよりも繊維径が大きい繊維Ｂとを含み、ガーレ式剛軟度が２０００ｍｇｆ以上であることを特徴とする不織布が記載されている。 Currently, non-woven fabrics are used in various applications such as filter media for air filters, filter media for oil filters, oil absorbents, sound absorbing materials, shock absorbing materials, heat insulating materials, and heat insulating materials.
For example, Patent Document 1 describes ultrafine fibers A having a fiber diameter D of 100 to 1000 nm and the ultrafine fibers A for the purpose of providing a non-woven fabric and a bag filter filter medium having excellent pleating performance as well as collection performance. A non-woven fabric containing a fiber B having a fiber diameter larger than that of the fiber A and having a Gale-type rigidity and softness of 2000 mgf or more is described.
　また、特許文献２には、よりエネルギー消費が少なく、高効率で低圧力損失である、エアフィルタ用濾材を提供することを目的として、ガラス繊維を主体とするエアフィルタ用濾材であり、前記ガラス繊維がチョップドストランドガラス繊維及び極細ガラス繊維を含有しており、かつ、前記エアフィルタ用濾材の繊維径分布において、１．５μｍより大きく２．９μｍ以下の範囲の累積頻度が２～１５％であることを特徴とするエアフィルタ用濾材が記載されている。 Further, Patent Document 2 describes an air filter filter medium mainly made of glass fiber for the purpose of providing an air filter filter medium that consumes less energy, has high efficiency, and has a low pressure loss. The fibers contain chopped strand glass fibers and ultrafine glass fibers, and the cumulative frequency in the range of more than 1.5 μm and 2.9 μm or less in the fiber diameter distribution of the air filter filter medium is 2 to 15%. A filter medium for an air filter, which is characterized by the above, is described.
特開２０１９－９９９４６号公報JP-A-2019-999946 特開２０１９－１７７３３１号公報Japanese Unexamined Patent Publication No. 2019-177331
　本発明の目的は、エアフィルタ用濾材として特に有用な、繊維集合体を提供することである。 An object of the present invention is to provide a fiber aggregate which is particularly useful as a filter medium for an air filter.
　本発明者等は、鋭意検討の結果、平均繊維径及び繊維径の分布を特定の範囲とすることにより、上記の課題が解決されることを見出した。
　すなわち、本発明は、以下の＜１＞～＜１１＞に関する。
　＜１＞　繊維集合体を構成する繊維の平均繊維径が６００ｎｍ以上１５００ｎｍ以下であり、繊維径１μｍ以上２μｍ未満の繊維の含有率が１０％以上５０％以下であり、繊維集合体を構成する繊維が、熱可塑性樹脂を主成分として含む、繊維集合体。
　＜２＞　繊維径が４００ｎｍ以上１０００ｎｍ未満の繊維を３５％以上含有する、＜１＞に記載の繊維集合体。
　＜３＞　繊維径が２μｍ以上の繊維の含有率が２０％以下である、＜１＞又は＜２＞に記載の繊維集合体。
　＜４＞　繊維径が４００ｎｍ以上６００ｎｍ未満の繊維の含有率が５％以上４０％以下である、＜１＞～＜３＞のいずれかに記載の繊維集合体。
　＜５＞　繊維径が６００ｎｍ以上８００ｎｍ未満の繊維の含有率が５％以上４０％以下である、＜１＞～＜４＞のいずれかに記載の繊維集合体。
　＜６＞　繊維径が８００ｎｍ以上１０００ｎｍ未満の繊維の含有率が５％以上４０％以下である、＜１＞～＜５＞のいずれかに記載の繊維集合体。
　＜７＞　繊維径が４００ｎｍ未満の繊維の含有率が２０％以下である、＜１＞～＜６＞のいずれかに記載の繊維集合体。
　＜８＞　前記繊維集合体が、乾式の繊維集合体である、＜１＞～＜７＞のいずれかに記載の繊維集合体。
　＜９＞　前記熱可塑性樹脂が、ポリオレフィン樹脂及びポリエステル樹脂から選択される少なくとも１つである、＜１＞～＜８＞のいずれかに記載の繊維集合体。
　＜１０＞　前記熱可塑性樹脂が、ポリプロピレン及びポリブチレンテレフタレートから選択される少なくとも１つである、＜１＞～＜９＞のいずれかに記載の繊維集合体。
　＜１１＞　前記繊維集合体の坪量のＣＶ値が２０％以下である、＜１＞～＜１０＞のいずれかに記載の繊維集合体。 As a result of diligent studies, the present inventors have found that the above problems can be solved by setting the average fiber diameter and the distribution of the fiber diameter within a specific range.
That is, the present invention relates to the following <1> to <11>.
<1> The average fiber diameter of the fibers constituting the fiber aggregate is 600 nm or more and 1500 nm or less, the content of the fibers having a fiber diameter of 1 μm or more and less than 2 μm is 10% or more and 50% or less, and the fibers constituting the fiber aggregate. However, a fiber aggregate containing a thermoplastic resin as a main component.
<2> The fiber aggregate according to <1>, which contains 35% or more of fibers having a fiber diameter of 400 nm or more and less than 1000 nm.
<3> The fiber aggregate according to <1> or <2>, wherein the content of fibers having a fiber diameter of 2 μm or more is 20% or less.
<4> The fiber aggregate according to any one of <1> to <3>, wherein the content of fibers having a fiber diameter of 400 nm or more and less than 600 nm is 5% or more and 40% or less.
<5> The fiber aggregate according to any one of <1> to <4>, wherein the content of fibers having a fiber diameter of 600 nm or more and less than 800 nm is 5% or more and 40% or less.
<6> The fiber aggregate according to any one of <1> to <5>, wherein the content of fibers having a fiber diameter of 800 nm or more and less than 1000 nm is 5% or more and 40% or less.
<7> The fiber aggregate according to any one of <1> to <6>, wherein the content of fibers having a fiber diameter of less than 400 nm is 20% or less.
<8> The fiber aggregate according to any one of <1> to <7>, wherein the fiber aggregate is a dry type fiber aggregate.
<9> The fiber aggregate according to any one of <1> to <8>, wherein the thermoplastic resin is at least one selected from a polyolefin resin and a polyester resin.
<10> The fiber aggregate according to any one of <1> to <9>, wherein the thermoplastic resin is at least one selected from polypropylene and polybutylene terephthalate.
<11> The fiber aggregate according to any one of <1> to <10>, wherein the CV value of the basis weight of the fiber aggregate is 20% or less.
　本発明によれば、エアフィルタ用濾材として特に有用な、繊維集合体を提供することができる。 According to the present invention, it is possible to provide a fiber aggregate which is particularly useful as a filter medium for an air filter.
図１は、メルトブロー装置１の概略を示す模式図である。FIG. 1 is a schematic view showing an outline of the melt blow device 1.
［繊維集合体］
　本発明の繊維集合体は、繊維集合体を構成する繊維の平均繊維径が６００ｎｍ以上１５００ｎｍ以下であり、繊維径１μｍ以上２μｍ未満の繊維の含有率が１０％以上５０％以下であり、繊維集合体を構成する繊維が、熱可塑性樹脂を主成分として含む。
　本発明によれば、低圧損かつ高捕集率であり、エアフィルタ用濾材として有用な繊維集合体が得られる。上述の効果が得られる詳細な理由な不明であるが、一部は以下のように考えられる。
　繊維径１μｍ以上２μｍ未満の繊維の含有率を上記の範囲とすることにより、大きな繊維径を有する繊維が適度に存在することで、繊維集合体に適度な空隙を与え、圧力損失が小さくなると考えられる。一方、平均繊維径を１５００ｎｍ以下とすることにより、高捕集率な繊維集合体が得られると考えられ、平均繊維径を６００ｎｍ以上とすることにより、圧力損失が小さくなると考えられる。
　本発明は、繊維集合体を構成する繊維径の平均繊維径及び繊維径分布を特定の範囲とすることにより、エアフィルタ用濾材として特に有用な繊維集合体となることを見出したものである。
　以下、本発明を更に詳細に説明する。 [Fiber aggregate]
In the fiber assembly of the present invention, the average fiber diameter of the fibers constituting the fiber aggregate is 600 nm or more and 1500 nm or less, the content of fibers having a fiber diameter of 1 μm or more and less than 2 μm is 10% or more and 50% or less, and the fiber assembly The fibers that make up the body contain thermoplastic resin as the main component.
According to the present invention, a fiber aggregate which has a low pressure loss and a high collection rate and is useful as a filter medium for an air filter can be obtained. Although the detailed reason why the above effects are obtained is unknown, some of them are considered as follows.
By setting the content of fibers having a fiber diameter of 1 μm or more and less than 2 μm in the above range, it is considered that the appropriate presence of fibers having a large fiber diameter gives an appropriate void to the fiber aggregate and reduces the pressure loss. Be done. On the other hand, it is considered that a fiber aggregate having a high collection rate can be obtained by setting the average fiber diameter to 1500 nm or less, and it is considered that the pressure loss is reduced by setting the average fiber diameter to 600 nm or more.
The present invention has found that by setting the average fiber diameter and the fiber diameter distribution of the fiber diameters constituting the fiber aggregate within a specific range, the fiber aggregate becomes particularly useful as a filter medium for an air filter.
Hereinafter, the present invention will be described in more detail.
＜繊維径＞
〔平均繊維径〕
　本発明の繊維集合体を構成する繊維の平均繊維径は、６００ｎｍ以上１５００ｎｍ以下である。繊維集合体を構成する繊維の平均繊維径が上記範囲内であると、低圧損かつ高捕集率となる。
　前記平均繊維径は、より低圧損かつ高捕集率とする観点から、好ましくは７００ｎｍ以上、より好ましくは８００ｎｍ以上、更に好ましくは９００ｎｍ以上であり、そして、好ましくは１４５０ｎｍ以下、より好ましくは１４００ｎｍ以下、更に好ましくは１３００ｎｍ以下である。
　繊維集合体を構成する繊維の平均繊維径は、実施例に記載の方法により測定される。 <Fiber diameter>
[Average fiber diameter]
The average fiber diameter of the fibers constituting the fiber aggregate of the present invention is 600 nm or more and 1500 nm or less. When the average fiber diameter of the fibers constituting the fiber aggregate is within the above range, low pressure loss and high collection rate are obtained.
The average fiber diameter is preferably 700 nm or more, more preferably 800 nm or more, further preferably 900 nm or more, and preferably 1450 nm or less, more preferably 1400 nm or less, from the viewpoint of lower pressure loss and high collection rate. , More preferably 1300 nm or less.
The average fiber diameter of the fibers constituting the fiber aggregate is measured by the method described in Examples.
〔繊維径１μｍ以上２μｍ未満の繊維の含有率〕
　本発明の繊維集合体を構成する繊維のうち、繊維径が１μｍ以上２μｍ未満の繊維の含有率は１０％以上５０％以下である。繊維径が１μｍ以上２μｍ未満の繊維の含有率が上記範囲内であると、低圧損かつ高捕集率となる。
　前記繊維径１μｍ以上２μｍ未満の繊維の含有率は、好ましくは１５％以上、より好ましくは１８％以上、更に好ましくは２０％以上であり、そして、好ましくは４７％以下、より好ましくは４５％以下、更に好ましくは４２％以下である。
　繊維径が１μｍ以上２μｍ未満の繊維の含有率は、実施例に記載の方法により測定される。 [Fiber content of fibers with a fiber diameter of 1 μm or more and less than 2 μm]
Among the fibers constituting the fiber aggregate of the present invention, the content of fibers having a fiber diameter of 1 μm or more and less than 2 μm is 10% or more and 50% or less. When the content of fibers having a fiber diameter of 1 μm or more and less than 2 μm is within the above range, low pressure loss and high collection rate are obtained.
The content of the fibers having a fiber diameter of 1 μm or more and less than 2 μm is preferably 15% or more, more preferably 18% or more, further preferably 20% or more, and preferably 47% or less, more preferably 45% or less. , More preferably 42% or less.
The content of fibers having a fiber diameter of 1 μm or more and less than 2 μm is measured by the method described in Examples.
〔繊維径４００ｎｍ以上１０００ｎｍ未満の繊維の含有率〕
　本発明の繊維集合体を構成する繊維のうち、繊維径が４００ｎｍ以上１０００ｎｍ未満の繊維の含有率は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは３５％以上、より好ましくは３６％以上、更に好ましくは３８％以上であり、そして、好ましくは９０％以下、より好ましくは８５％以下、更に好ましくは７５％以下である。
　繊維径が４００ｎｍ以上１０００ｎｍ未満の繊維の含有率は、実施例に記載の方法により測定される。 [Fiber content of fibers with a fiber diameter of 400 nm or more and less than 1000 nm]
Among the fibers constituting the fiber aggregate of the present invention, the content of the fiber having a fiber diameter of 400 nm or more and less than 1000 nm is preferably 35% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 36% or more, more preferably 38% or more, and preferably 90% or less, more preferably 85% or less, still more preferably 75% or less.
The content of fibers having a fiber diameter of 400 nm or more and less than 1000 nm is measured by the method described in Examples.
〔繊維径２μｍ以上の繊維の含有率〕
　本発明の繊維集合体を構成する繊維のうち、繊維径が２μｍ以上の繊維の含有率は、高捕集率な繊維集合体を得る観点から、好ましくは２０％以下、より好ましくは１８％以下、更に好ましくは１６％以下である。
　繊維径が２μｍ以上の繊維の含有率は、実施例に記載の方法により測定される。 [Fiber content of fibers with a fiber diameter of 2 μm or more]
Among the fibers constituting the fiber aggregate of the present invention, the content of the fiber having a fiber diameter of 2 μm or more is preferably 20% or less, more preferably 18% or less from the viewpoint of obtaining a fiber aggregate having a high collection rate. , More preferably 16% or less.
The content of fibers having a fiber diameter of 2 μm or more is measured by the method described in Examples.
〔繊維径４００ｎｍ以上６００ｎｍ未満の繊維の含有率〕
　本発明の繊維集合体を構成する繊維のうち、繊維径が４００ｎｍ以上６００ｎｍ未満の繊維の含有率は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは５％以上であり、そして、好ましくは４０％以下、より好ましくは３０％以下、更に好ましくは２５％以下である。
　繊維径が４００ｎｍ以上６００ｎｍ未満の繊維の含有率は、実施例に記載の方法により測定される。 [Fiber content of fibers with a fiber diameter of 400 nm or more and less than 600 nm]
Among the fibers constituting the fiber aggregate of the present invention, the content of the fiber having a fiber diameter of 400 nm or more and less than 600 nm is preferably 5% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. And preferably 40% or less, more preferably 30% or less, still more preferably 25% or less.
The content of fibers having a fiber diameter of 400 nm or more and less than 600 nm is measured by the method described in Examples.
〔繊維径６００ｎｍ以上８００ｎｍ未満の繊維の含有率〕
　本発明の繊維集合体を構成する繊維のうち、繊維径が６００ｎｍ以上８００ｎｍ未満の繊維の含有率は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは５％以上、より好ましくは８％以上、更に好ましくは１０％以上であり、そして、好ましくは４０％以下、より好ましくは３５％以下、更に好ましくは３０％以下である。
　繊維径が６００ｎｍ以上８００ｎｍ未満の繊維幅の含有率は、実施例に記載の方法により測定される。 [Fiber content of fibers with a fiber diameter of 600 nm or more and less than 800 nm]
Among the fibers constituting the fiber aggregate of the present invention, the content of the fiber having a fiber diameter of 600 nm or more and less than 800 nm is preferably 5% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 8% or more, more preferably 10% or more, and preferably 40% or less, more preferably 35% or less, still more preferably 30% or less.
The content of the fiber width having a fiber diameter of 600 nm or more and less than 800 nm is measured by the method described in Examples.
〔繊維径８００ｎｍ以上１０００ｎｍ未満の繊維の含有率〕
　本発明の繊維集合体を構成する繊維のうち、繊維径が８００ｎｍ以上１０００ｎｍ未満の繊維の含有率は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは５％以上、より好ましくは６％以上、更に好ましくは８％以上であり、そして、好ましくは４０％以下、より好ましくは３５％以下、更に好ましくは３０％以下である。
　繊維径が８００ｎｍ以上１０００ｎｍ未満の繊維幅の含有率は、実施例に記載の方法により測定される。 [Fiber content of fibers with a fiber diameter of 800 nm or more and less than 1000 nm]
Among the fibers constituting the fiber aggregate of the present invention, the content of the fiber having a fiber diameter of 800 nm or more and less than 1000 nm is preferably 5% or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 6% or more, more preferably 8% or more, and preferably 40% or less, more preferably 35% or less, still more preferably 30% or less.
The content of the fiber width having a fiber diameter of 800 nm or more and less than 1000 nm is measured by the method described in Examples.
〔繊維径４００ｎｍ未満の繊維の含有率〕
　本発明の繊維集合体を構成する繊維のうち、繊維径が４００ｎｍ未満の繊維の含有率は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは２０％以下であり、より好ましくは１８％以下、更に好ましくは１５％以下である。また、その下限は特に限定されず、０％であってもよい。
　繊維径が４００ｎｍ未満の繊維幅の含有率は、実施例に記載の方法により測定される。 [Fiber content with a fiber diameter of less than 400 nm]
Among the fibers constituting the fiber aggregate of the present invention, the content of the fiber having a fiber diameter of less than 400 nm is preferably 20% or less from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate, and more. It is preferably 18% or less, more preferably 15% or less. Further, the lower limit thereof is not particularly limited and may be 0%.
The content of fiber widths with a fiber diameter of less than 400 nm is measured by the method described in the Examples.
〔幾何標準偏差〕
　本発明の繊維集合体を構成する繊維全体の繊維径の幾何標準偏差は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは３．０μｍ以下、より好ましくは２．６μｍ以下、更に好ましくは２．２μｍ以下であり、そして、好ましくは０．５μｍ以上、より好ましくは０．８μｍ以上、更に好ましくは１．０μｍ以上である。なお、繊維全体の繊維径の幾何標準偏差が上記の範囲である繊維集合体は、面内均一性に優れるので好ましい。
　本発明の繊維集合体を構成する繊維のうち、繊維径が１μｍ未満（１０００ｎｍ未満）の繊維の繊維径の幾何標準偏差は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは５．０μｍ以下、より好ましくは３．０μｍ以下、更に好ましくは２．２μｍ以下であり、そして、製造容易性の観点から、好ましくは０．３μｍ以上、より好ましくは０．５μｍ以上、更に好ましくは１．０μｍ以上である。
　本発明の繊維集合体を構成する繊維のうち、繊維径が１μｍ以上の繊維の繊維径の幾何標準偏差は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは３．０μｍ以下、より好ましくは２．０μｍ以下、更に好ましくは１．５μｍ以下であり、そして、製造容易性の観点から、好ましくは０．１μｍ以上、より好ましくは０．３μｍ以上、更に好ましくは０．５μｍ以上である。 [Geometric standard deviation]
The geometric standard deviation of the fiber diameter of the entire fiber constituting the fiber aggregate of the present invention is preferably 3.0 μm or less, more preferably 2.6 μm or less, from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is more preferably 2.2 μm or less, and preferably 0.5 μm or more, more preferably 0.8 μm or more, still more preferably 1.0 μm or more. A fiber aggregate in which the geometric standard deviation of the fiber diameter of the entire fiber is in the above range is preferable because it is excellent in in-plane uniformity.
Among the fibers constituting the fiber aggregate of the present invention, the geometric standard deviation of the fiber diameter of the fiber having a fiber diameter of less than 1 μm (less than 1000 nm) is preferable from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. Is 5.0 μm or less, more preferably 3.0 μm or less, still more preferably 2.2 μm or less, and from the viewpoint of ease of production, preferably 0.3 μm or more, more preferably 0.5 μm or more, still more preferable. Is 1.0 μm or more.
Among the fibers constituting the fiber aggregate of the present invention, the geometric standard deviation of the fiber diameter of the fiber having a fiber diameter of 1 μm or more is preferably 3.0 μm from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. Below, it is more preferably 2.0 μm or less, still more preferably 1.5 μm or less, and from the viewpoint of ease of production, it is preferably 0.1 μm or more, more preferably 0.3 μm or more, still more preferably 0.5 μm. That is all.
　本発明の繊維集合体を構成する繊維は、上述の繊維径の分布を有することが好ましいが、大径の繊維と、小径の繊維とを混合して使用するのではなく、分布が広く、場合によっては、２つ以上のピークが存在するような繊維の集合であることが、製造容易性及び面内均一性の観点から好ましい。 The fibers constituting the fiber aggregate of the present invention preferably have the above-mentioned fiber diameter distribution, but the case where the large diameter fiber and the small diameter fiber are not mixed and used but have a wide distribution. Depending on the case, an aggregate of fibers having two or more peaks is preferable from the viewpoint of ease of production and in-plane uniformity.
＜熱可塑性樹脂＞
　本発明の繊維集合体を構成する繊維は、熱可塑性樹脂を主成分として含む。本発明の繊維集合体は、後述するようにメルトブロー法により製造することが好ましく、繊維原料として、熱可塑性樹脂が好適である。
　熱可塑性樹脂としては、ポリエチレン（ＰＥ）、ポリプロピレン（ＰＰ）等のポリオレフィン樹脂；ポリブチレンテレフタレート（ＰＢＴ）、ポリエチレンテレフタレート（ＰＥＴ）等のポリエステル樹脂；ポリアミド樹脂（ＰＡ）等が例示される。これらの中でも、熱可塑性樹脂は、好ましくはポリオレフィン樹脂及びポリエステル樹脂から選択される少なくとも１つであり、より好ましくはポリプロピレン及びポリブチレンテレフタレートから選択される少なくとも１つであり、更に好ましくはポリプロピレンである。
　熱可塑性樹脂は、１種単独で使用してもよく、２種以上を併用してもよい。 <Thermoplastic resin>
The fibers constituting the fiber aggregate of the present invention contain a thermoplastic resin as a main component. The fiber aggregate of the present invention is preferably produced by the melt blow method as described later, and a thermoplastic resin is suitable as the fiber raw material.
Examples of the thermoplastic resin include polyolefin resins such as polyethylene (PE) and polypropylene (PP); polyester resins such as polybutylene terephthalate (PBT) and polyethylene terephthalate (PET); polyamide resins (PA) and the like. Among these, the thermoplastic resin is preferably at least one selected from a polyolefin resin and a polyester resin, more preferably at least one selected from polypropylene and polybutylene terephthalate, and further preferably polypropylene. ..
The thermoplastic resin may be used alone or in combination of two or more.
　本発明の繊維集合体を構成する繊維は、熱可塑性樹脂を５０質量％以上含有し、好ましくは７０質量％以上、より好ましく９０質量％以上、更に好ましくは９５質量％以上であり、そして、１００質量％以下であり、１００質量％であってもよい。 The fibers constituting the fiber assembly of the present invention contain 50% by mass or more of a thermoplastic resin, preferably 70% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and 100. It is not more than% by mass and may be 100% by mass.
　本発明において、繊維集合体は、上記熱可塑性樹脂に加え、他の成分を含有していてもよい。他の成分としては、界面活性剤、着色剤、リン系、フェノール系等の酸化防止剤、ベンゾトリアゾール系等の耐候安定剤、ヒンダードアミン系等の耐光安定剤、ブロッキング防止剤、ステアリン酸カルシウム等の分散剤、滑剤、核剤、顔料、柔軟剤、親水剤、撥水剤、助剤、撥水剤、充填剤、抗菌剤、農薬、防虫剤、薬剤、天然油、合成油などが挙げられる。 In the present invention, the fiber aggregate may contain other components in addition to the above-mentioned thermoplastic resin. Other components include surfactants, colorants, phosphorus-based and phenol-based antioxidants, benzotriazole-based weather-resistant stabilizers, hindered amine-based light-resistant stabilizers, blocking inhibitors, and dispersion of calcium stearate. Examples include agents, lubricants, nucleating agents, pigments, softeners, hydrophilic agents, water repellents, auxiliaries, water repellents, fillers, antibacterial agents, pesticides, insect repellents, chemicals, natural oils, synthetic oils and the like.
＜繊維集合体の製造方法＞
　本発明の繊維集合体は、上述した平均繊維径及び繊維径分布が得られれば特に限定されず、乾式で製造してもよく、湿式で製造してもよいが、上述した平均繊維径及び繊維径分布を得るためには、乾式で製造することが好ましく、乾式の繊維集合体の製造方法としては、メルトブロー法、スパンボンド法等が例示される。これらの中でも、メルトブロー法で作製することが好ましく、熱可塑性樹脂を溶融して押出機のノズルから吐出し、高速高温の気流で噴き出すメルトブロー法で製造することがより好ましい。
　より詳細には、高温雰囲気下において、溶融した熱可塑性樹脂を上方から下方に向けて吐出すると共に、吐出された熱可塑性樹脂に向けて略水平方向より、エアノズルから高温かつ高圧の空気を吹き付けて、溶融した熱可塑性樹脂を繊維状の樹脂とし、該繊維状の樹脂を捕集して、繊維集合体を製造することが好ましい。上記の方法では、エアノズルから吹き付けられた空気により、溶融した熱可塑性樹脂が延伸されて繊維状の樹脂となる。
　ここで、捕集までの距離が長いほど、密度が低い繊維集合体が得られる傾向にある。また、吐出された熱可塑性樹脂に吹き付ける空気の温度を上げるほど、繊維状の樹脂の繊維径が小さくなる傾向にあり、吹き付ける空気の風量を上げるほど、繊維状の樹脂の繊維径が小さくなる傾向にある。また、溶融した熱可塑性樹脂の時間あたりの吐出量を下げると、繊維径が小さくなる傾向にある。
　また、捕集した繊維状の樹脂を巻き取りながら、繊維集合体を製造するが、このとき、巻き取り速度を遅くすることで、目付（坪量）を上げることができる。 <Manufacturing method of fiber aggregate>
The fiber aggregate of the present invention is not particularly limited as long as the above-mentioned average fiber diameter and fiber diameter distribution can be obtained, and may be produced by a dry method or a wet method, but the above-mentioned average fiber diameter and fiber may be produced. In order to obtain the diameter distribution, it is preferable to manufacture by a dry method, and examples of the method for manufacturing a dry fiber aggregate include a melt blow method and a spunbond method. Among these, it is preferable to manufacture by the melt blow method, and it is more preferable to manufacture by the melt blow method in which the thermoplastic resin is melted, discharged from the nozzle of the extruder, and ejected by a high-speed high-temperature air flow.
More specifically, in a high temperature atmosphere, the molten thermoplastic resin is discharged from above to below, and high temperature and high pressure air is blown from the air nozzle toward the discharged thermoplastic resin from a substantially horizontal direction. It is preferable to use the molten thermoplastic resin as a fibrous resin and collect the fibrous resin to produce a fiber aggregate. In the above method, the molten thermoplastic resin is stretched by the air blown from the air nozzle to become a fibrous resin.
Here, the longer the distance to collection, the lower the density of fiber aggregates tends to be obtained. Further, the higher the temperature of the air blown onto the discharged thermoplastic resin, the smaller the fiber diameter of the fibrous resin tends to be, and the higher the air volume of the blown air, the smaller the fiber diameter of the fibrous resin tends to be. It is in. Further, when the discharge amount of the molten thermoplastic resin per hour is reduced, the fiber diameter tends to be reduced.
Further, the fiber aggregate is produced while winding the collected fibrous resin. At this time, the basis weight (basis weight) can be increased by slowing down the winding speed.
　本発明において特に好適な繊維集合体の製造方法について、図１を参照して詳述する。図１は、メルトブロー装置１の概略を示す模式図である。
　メルトブロー装置１は、主として樹脂供給部１０と、空気流発生部２０と、捕集部３０と、過熱蒸気供給部４０と、を有する。
　樹脂供給部１０は、主として、ホッパ１１と押出機１２と、ダイ１３と、樹脂ノズル１４と、を有する。熱可塑性樹脂の原料チップをホッパ１１に投入し、押出機１２に備えられた図示しないヒータで加熱して熱可塑性樹脂を溶融し、溶融した熱可塑性樹脂を得る。押出機１２は、図示しないギアポンプにより、溶融した熱可塑性樹脂をダイ１３へと押し出す。
　樹脂ノズル１４は、ダイ１３に設けられており、溶融した熱可塑性樹脂を吐出する。樹脂ノズル１４からは、溶融した熱可塑性樹脂が上方から下方に向けて吐出される。 A method for producing a fiber aggregate particularly suitable in the present invention will be described in detail with reference to FIG. FIG. 1 is a schematic view showing an outline of the melt blow device 1.
The melt blow device 1 mainly includes a resin supply unit 10, an air flow generation unit 20, a collection unit 30, and a superheated steam supply unit 40.
The resin supply unit 10 mainly includes a hopper 11, an extruder 12, a die 13, and a resin nozzle 14. The raw material chip of the thermoplastic resin is put into the hopper 11 and heated by a heater (not shown) provided in the extruder 12 to melt the thermoplastic resin to obtain the melted thermoplastic resin. The extruder 12 pushes the molten thermoplastic resin into the die 13 by a gear pump (not shown).
The resin nozzle 14 is provided on the die 13 and discharges the molten thermoplastic resin. From the resin nozzle 14, the molten thermoplastic resin is discharged from the upper side to the lower side.
　空気流発生部２０は、主として圧縮空気を生成するコンプレッサ２１と、圧縮空気が通過する配管２２と、レギュレータ２３と、配管２２を加熱するヒータ２４と、エアノズル２５と、を有する。コンプレッサ２１、配管２２、及びヒータ２４は、高温かつ高圧の空気を生成する高温高圧空気生成部に相当する。エアノズル２５は、樹脂ノズル１４に隣接して設けられており、高温高圧空気生成部で生成された高温かつ高圧の空気を吐出する。
　エアノズル２５から吐出する空気の温度は、熱可塑性樹脂の種類等により適宜選択すればよいが、所望の平均繊維径及び繊維径分布を得る観点から、好ましくは４００℃以上、より好ましくは４５０℃以上、更に好ましくは４７０℃以上であり、そして、好ましくは８００℃以下、より好ましくは７００℃以下、更に好ましくは６５０℃以下、より更に好ましくは６２０℃以下である。
　なお、樹脂ノズル１４及びエアノズル２５は、図の紙面奥に向かって、一列に並んで設けられており、エアノズル２５の配列方向は、樹脂ノズル１４の配列方向と略並行であり、エアノズル２５の配置領域は、樹脂ノズル１４の配置領域を含む。 The air flow generating unit 20 mainly includes a compressor 21 that generates compressed air, a pipe 22 through which compressed air passes, a regulator 23, a heater 24 that heats the pipe 22, and an air nozzle 25. The compressor 21, the pipe 22, and the heater 24 correspond to a high-temperature and high-pressure air generating unit that generates high-temperature and high-pressure air. The air nozzle 25 is provided adjacent to the resin nozzle 14, and discharges high-temperature and high-pressure air generated by the high-temperature and high-pressure air generation unit.
The temperature of the air discharged from the air nozzle 25 may be appropriately selected depending on the type of the thermoplastic resin and the like, but from the viewpoint of obtaining a desired average fiber diameter and fiber diameter distribution, it is preferably 400 ° C. or higher, more preferably 450 ° C. or higher. It is more preferably 470 ° C. or higher, and preferably 800 ° C. or lower, more preferably 700 ° C. or lower, still more preferably 650 ° C. or lower, and even more preferably 620 ° C. or lower.
The resin nozzles 14 and the air nozzles 25 are provided side by side in a row toward the back of the paper in the figure, and the arrangement direction of the air nozzles 25 is substantially parallel to the arrangement direction of the resin nozzles 14, and the air nozzles 25 are arranged. The region includes an arrangement region of the resin nozzle 14.
　エアノズル２５からは、高温かつ高圧の空気が略水平方向に吐出される。エアノズル２５から吐出される空気の流量は、所望の平均繊維径及び繊維径分布を得る観点から、好ましくは５Ｌ／ｍｉｎ以上、より好ましくは１０Ｌ／ｍｉｎ以上、更に好ましくは１５Ｌ／ｍｉｎ以上であり、そして、好ましくは６０Ｌ／ｍｉｎ以下、より好ましくは４５Ｌ／ｍｉｎ以下、更に好ましくは３５Ｌ／ｍｉｎ以下である。エアノズル２５から吐出された空気を吹き付けることによって、樹脂ノズル１４から吐出された溶融熱可塑性樹脂が延伸されて、繊維状の樹脂となる。 High temperature and high pressure air is discharged from the air nozzle 25 in a substantially horizontal direction. The flow rate of the air discharged from the air nozzle 25 is preferably 5 L / min or more, more preferably 10 L / min or more, still more preferably 15 L / min or more, from the viewpoint of obtaining a desired average fiber diameter and fiber diameter distribution. Then, it is preferably 60 L / min or less, more preferably 45 L / min or less, and further preferably 35 L / min or less. By blowing the air discharged from the air nozzle 25, the molten thermoplastic resin discharged from the resin nozzle 14 is stretched to become a fibrous resin.
　捕集部３０は、主として、繊維状の樹脂を捕集する略円筒形状のサクションドラム３１と、ブロワ３２と、ブロワ３２に接続された吸引部３３と、不織布５１、５２が巻回された不織布ロール３４、３５と、巻取りドラム３６と、を有する。ここで、不織布５１は基材であり、不織布５２は被覆材（カバー材）である。 The collecting portion 30 is mainly a suction drum 31 having a substantially cylindrical shape for collecting fibrous resin, a blower 32, a suction portion 33 connected to the blower 32, and a non-woven fabric around which the non-woven fabrics 51 and 52 are wound. It has rolls 34 and 35 and a take-up drum 36. Here, the non-woven fabric 51 is a base material, and the non-woven fabric 52 is a covering material (cover material).
　エアノズル２５から吐出された空気により、樹脂ノズル１４から吐出された溶融ポリマーは微細な繊維（例えば、ナノファイバ）となり、サクションドラム３１に吹き付けられる。サクションドラム３１には、不織布ロール３４から引き出された不織布５１が巻き掛けられており、吸引部３３から空気が吸引されることで繊維状の樹脂が不織布５１の表面に吸着する。
　不織布５１の端は巻取りドラム３６に設けられている。巻取りドラム３６が一定の速度で回転することで、繊維状の樹脂が表面に吸着した不織布５１は、巻取りドラム３６に向けて一定速度で移動する。
　また、不織布ロール３５から引き出された不織布５２も、端が巻取りドラム３６に設けられている。従って、巻取りドラム３６が一定の速度で回転することで、不織布５２が不織布５１表面の繊維層を覆う。そして、不織布５２が不織布５１表面の繊維層を覆ったものをカレンダー加工等により一体化することで、繊維集合体が不織布５１、５２によって挟持された構造が得られ、これは、引取りドラム３６に巻回される。
　本発明において、基材及び被覆材は必須の構成要件ではなく、繊維集合体は、樹脂ノズル１４から吐出された樹脂が繊維状樹脂となって積層した部分を意味する。従って、本発明の繊維集合体は、基材及び被覆材に挟持された形態で使用されてもよく、繊維集合体のみを使用してもよい。 Due to the air discharged from the air nozzle 25, the molten polymer discharged from the resin nozzle 14 becomes fine fibers (for example, nanofibers) and is sprayed onto the suction drum 31. The non-woven fabric 51 drawn from the non-woven fabric roll 34 is wound around the suction drum 31, and the fibrous resin is adsorbed on the surface of the non-woven fabric 51 by sucking air from the suction unit 33.
The end of the non-woven fabric 51 is provided on the take-up drum 36. As the take-up drum 36 rotates at a constant speed, the non-woven fabric 51 on which the fibrous resin is adsorbed on the surface moves toward the take-up drum 36 at a constant speed.
Further, the non-woven fabric 52 drawn from the non-woven fabric roll 35 is also provided at the end of the take-up drum 36. Therefore, when the take-up drum 36 rotates at a constant speed, the non-woven fabric 52 covers the fiber layer on the surface of the non-woven fabric 51. Then, by integrating the non-woven fabric 52 covering the fiber layer on the surface of the non-woven fabric 51 by calendar processing or the like, a structure in which the fiber aggregate is sandwiched between the non-woven fabrics 51 and 52 is obtained, which is the take-up drum 36. It is wound around.
In the present invention, the base material and the coating material are not essential constituent requirements, and the fiber aggregate means a portion in which the resin discharged from the resin nozzle 14 is laminated as a fibrous resin. Therefore, the fiber aggregate of the present invention may be used in a form sandwiched between the base material and the covering material, or only the fiber aggregate may be used.
　過熱蒸気供給部４０は、樹脂ノズル１４、エアノズル２５、及びサクションドラム３１により囲まれた空間に過熱蒸気を供給する。樹脂ノズル１４、エアノズル２５、及びサクションドラム３１により囲まれた空間は、エアノズル２５から吹き出された空気が溶融した熱可塑性樹脂を繊維化する領域である。過熱蒸気供給部４０は、主として、過熱蒸気を発生させる加熱器４１と、配管４２と、過熱蒸気ノズル４３とを有する。
　加熱器４１は、図示しないボイラー等により発生する飽和蒸気を更に熱し、高い温度の過熱蒸気を発生させる。過熱蒸気は、沸点より高い温度の乾いた水蒸気であり、例えば、２００℃以上７００℃以下の温度帯で使用される。
　加熱器４１で生成された過熱蒸気は、配管４２を介して、過熱蒸気ノズル４３に供給され、過熱蒸気ノズル４３から吐出される。過熱蒸気ノズル４３は、紙面の奥に向けて一列に並んで設けられており、過熱蒸気ノズル４３の配列方向は、樹脂ノズル１４及びエアノズル２５の配列方向と略並行であり、過熱蒸気ノズル４３の配置領域は、樹脂ノズル　１４及びエアノズル２５の配置領域を含む。
　過熱蒸気ノズル４３から、過熱蒸気を大量に供給することで、樹脂ノズル１４、エアノズル２５、及びサクションドラム３１により囲まれた空間を高温高湿雰囲気下に置くことができる。 The superheated steam supply unit 40 supplies superheated steam to the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31. The space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31 is a region where the air blown from the air nozzle 25 fibrates the molten thermoplastic resin. The superheated steam supply unit 40 mainly includes a heater 41 for generating superheated steam, a pipe 42, and a superheated steam nozzle 43.
The heater 41 further heats saturated steam generated by a boiler or the like (not shown) to generate superheated steam at a high temperature. The superheated steam is dry steam having a temperature higher than the boiling point, and is used, for example, in a temperature range of 200 ° C. or higher and 700 ° C. or lower.
The superheated steam generated by the heater 41 is supplied to the superheated steam nozzle 43 via the pipe 42, and is discharged from the superheated steam nozzle 43. The superheated steam nozzles 43 are provided side by side in a row toward the back of the paper surface, and the arrangement direction of the superheated steam nozzles 43 is substantially parallel to the arrangement direction of the resin nozzle 14 and the air nozzle 25. The arrangement area includes the arrangement area of the resin nozzle 14 and the air nozzle 25.
By supplying a large amount of superheated steam from the superheated steam nozzle 43, the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31 can be placed in a high temperature and high humidity atmosphere.
　なお、樹脂ノズル１４は、中心軸が略鉛直方向に沿っている。従って、樹脂ノズル１４から吐出された溶融した熱可塑性樹脂は、自重で鉛直下向きに落下する。
　また、エアノズル２５は、中心軸が略水平方向に沿っている。従って、高温かつ高圧の空気は、エアノズル２５から水平方向に吹き出す。
　エアノズル２５は、樹脂ノズル１４の中心軸と交差することが好ましい。つまり、エアノズル２５の先端は、樹脂ノズル１４の中心軸よりも前方に位置することが好ましい。エアノズル２５から吹き出した空気は随伴流が発生しており、樹脂ノズル１４から吐出された溶融した熱可塑性樹脂は、随伴流に乗って水平方向に吹き飛ばされ、その後、エアノズル２５から吐出された空気により前方に吹き飛ばされることで延伸されて繊維状の樹脂となり、エアノズル２５の前方に配置されたサクションドラム３１に吹き付けられる。
　なお、過熱蒸気ノズル４３は、中心軸が水平方向に傾いており、エアノズル２５の下方かつ後方からエアノズル２５に向けて過熱蒸気を吐出することが好ましい。過熱ノズル４３から吐出された過熱蒸気は、随伴流に乗って水平方向に流れ、樹脂ノズル１４、エアノズル２５、及びサクションドラム３１によって囲まれた雰囲気に供給される。過熱蒸気を随伴流に乗せることで、樹脂ノズル１４、エアノズル２５及びサクションドラム３１により囲まれた空間に過熱蒸気が広がりやすい。
　樹脂ノズル１４から吐出された溶融した熱可塑性樹脂は、過熱蒸気が樹脂ノズル１４、エアノズル２５、及びサクションドラム３１により囲まれた空間に供給されているため、高温雰囲気下で延伸されて繊維状となる。 The central axis of the resin nozzle 14 is substantially in the vertical direction. Therefore, the molten thermoplastic resin discharged from the resin nozzle 14 falls vertically downward under its own weight.
Further, the central axis of the air nozzle 25 is substantially horizontal. Therefore, the high temperature and high pressure air is blown out from the air nozzle 25 in the horizontal direction.
The air nozzle 25 preferably intersects the central axis of the resin nozzle 14. That is, the tip of the air nozzle 25 is preferably located in front of the central axis of the resin nozzle 14. An accompanying flow is generated in the air blown out from the air nozzle 25, and the molten thermoplastic resin discharged from the resin nozzle 14 is blown off in the horizontal direction by riding on the accompanying flow, and then by the air discharged from the air nozzle 25. By being blown forward, it is stretched to become a fibrous resin, which is sprayed onto the suction drum 31 arranged in front of the air nozzle 25.
The superheated steam nozzle 43 preferably has a central axis tilted in the horizontal direction, and discharges superheated steam toward the air nozzle 25 from below and behind the air nozzle 25. The superheated steam discharged from the superheated nozzle 43 flows horizontally along with the accompanying flow, and is supplied to the atmosphere surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31. By placing the superheated steam on the accompanying flow, the superheated steam easily spreads in the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31.
Since the superheated steam is supplied to the space surrounded by the resin nozzle 14, the air nozzle 25, and the suction drum 31, the molten thermoplastic resin discharged from the resin nozzle 14 is stretched in a high temperature atmosphere and becomes fibrous. Become.
＜繊維集合体の特性＞
〔繊維集合体の目付〕
　本発明において、エアフィルタ用に使用する場合には、繊維集合体の目付（坪量）は、低圧損かつ高捕集率な繊維集合体を得る観点から、好ましくは１０ｇ／ｍ２以上、より好ましくは１５ｇ／ｍ２以上、更に好ましくは２０ｇ／ｍ２以上、より更に好ましくは２５ｇ／ｍ２以上であり、そして、好ましくは５０ｇ／ｍ２以下、より好ましくは４０ｇ／ｍ２以下、更に好ましくは３５ｇ／ｍ２以下である。
　本発明の繊維集合体は、面内均一性に優れる点にも特徴があり、目付のＣＶ値は、好ましくは２０％以下、より好ましくは１６％以下、更に好ましくは１２％以下であり、そして、製造容易性の観点から、好ましくは０．５％以上、より好ましくは１％以上、更に好ましくは２％以上である。
　繊維集合体の目付及びＣＶ値は、実施例に記載の方法により測定される。 <Characteristics of fiber aggregate>
[Metsuke of fiber aggregate]
In the present invention, when used for an air filter, the texture (basis weight) of the fiber aggregate is preferably 10 g / m 2 or more from the viewpoint of obtaining a fiber aggregate having a low pressure loss and a high collection rate. It is preferably 15 g / m 2 or more, more preferably 20 g / m 2 or more, even more preferably 25 g / m 2 or more, and preferably 50 g / m 2 or less, more preferably 40 g / m 2 or less, even more preferably. Is 35 g / m 2 or less.
The fiber aggregate of the present invention is also characterized in that it is excellent in in-plane uniformity, and the CV value of the basis weight is preferably 20% or less, more preferably 16% or less, still more preferably 12% or less, and From the viewpoint of ease of production, it is preferably 0.5% or more, more preferably 1% or more, still more preferably 2% or more.
The basis weight and CV value of the fiber aggregate are measured by the method described in Examples.
〔繊維集合体の厚み〕
　本発明の繊維集合体の厚みは、用途によって適宜選択すればよいが、繊維集合体をエアフィルタ用途に使用する場合には、繊維集合体の厚みは、捕集率向上の観点から、好ましくは３０μｍ以上、より好ましくは４５μｍ以上、更に好ましくは６０μｍ以上、より更に好ましくは８５μｍ以上、より更に好ましくは１００μｍ以上であり、そして、圧損を減少させる観点から、好ましくは５００μｍ以下、より好ましくは４００μｍ以下、更に好ましくは３００μｍ以下、より更に好ましくは２４０μｍ以下、より更に好ましくは１８０μｍ以下である。
　繊維集合体をエアフィルタ用途に使用する場合、繊維集合体の厚みは、例えば、株式会社ミツトヨ製、シックネスゲージで測定される。
　なお、繊維集合体の厚みは、その用途に応じて適宜変更すればよく、より厚い繊維集合体とする場合には、その厚みは、側面に定規を立てて、自然厚を測定すればよい。 [Thickness of fiber aggregate]
The thickness of the fiber aggregate of the present invention may be appropriately selected depending on the intended use, but when the fiber aggregate is used for an air filter application, the thickness of the fiber aggregate is preferably selected from the viewpoint of improving the collection rate. It is 30 μm or more, more preferably 45 μm or more, further preferably 60 μm or more, still more preferably 85 μm or more, still more preferably 100 μm or more, and from the viewpoint of reducing pressure loss, it is preferably 500 μm or less, more preferably 400 μm or less. It is more preferably 300 μm or less, still more preferably 240 μm or less, and even more preferably 180 μm or less.
When the fiber aggregate is used for an air filter application, the thickness of the fiber aggregate is measured by, for example, a thickness gauge manufactured by Mitutoyo Co., Ltd.
The thickness of the fiber aggregate may be appropriately changed according to the intended use, and in the case of a thicker fiber aggregate, the thickness may be measured by setting a ruler on the side surface and measuring the natural thickness.
〔繊維集合体の０．３μｍ径の粒子の捕集率〕
　本発明の繊維集合体をエアフィルタ用濾材に使用する場合、透過風速５．３ｃｍ／ｓｅｃにおける０．３μｍ径の粒子の捕集率（捕集効率）は、好ましくは５５％以上、より好ましくは５７％以上、更に好ましくは６０％以上である。
　なお、前記捕集率はエアフィルタ用濾材を除電して、静電気による粒子の捕集効果を失わせて測定したものである。特定の平均繊維径及び繊維径の分布を有する繊維集合体とすることにより、優れた捕集性能を有する。
　前記捕集率は、実施例に記載の方法により測定される。 [Collection rate of 0.3 μm diameter particles of fiber aggregate]
When the fiber aggregate of the present invention is used as a filter medium for an air filter, the collection rate (collection efficiency) of particles having a diameter of 0.3 μm at a permeation wind speed of 5.3 cm / sec is preferably 55% or more, more preferably 55% or more. It is 57% or more, more preferably 60% or more.
The collection rate is measured by removing static electricity from the filter medium for an air filter to eliminate the effect of collecting particles due to static electricity. It has excellent collection performance by forming a fiber aggregate having a specific average fiber diameter and a distribution of fiber diameters.
The collection rate is measured by the method described in Examples.
〔繊維集合体の圧力損失〕
　本発明の繊維集合体をエアフィルタ用濾材に使用する場合、圧力損失が低いことが好ましく、透過風速を５．３ｃｍ／ｓｅｃとしたときの圧力損失は、好ましくは４０Ｐａ以下、より好ましくは３５Ｐａ以下、更に好ましくは３２Ｐａ以下である。
　前記圧力損失は、実施例に記載の方法により測定される。 [Pressure loss of fiber aggregate]
When the fiber aggregate of the present invention is used as a filter medium for an air filter, the pressure loss is preferably low, and the pressure loss when the permeation air velocity is 5.3 cm / sec is preferably 40 Pa or less, more preferably 35 Pa or less. , More preferably 32 Pa or less.
The pressure loss is measured by the method described in the examples.
〔ＰＦ値〕
　ＰＦ値は、捕集率と圧力損失とのバランスを示す値であり、エアフィルタ用濾材の性能を示す指標として一般的に使用されており、下記式（１）で表される。
　ＰＦ値(1/kPa)
　　＝-log10{(100-捕集率(%))/100}/(圧力損失(Pa)/1000)　（１）
　ＰＦ値が高いほど、エアフィルタ用濾材として高性能であることを意味する。
　本発明の繊維集合体をエアフィルタ用濾材に使用する場合、透過風速５．３ｍ／ｓｅｃにおける０．３μｍ径の粒子の捕集率と、透過風速５．３ｍ／ｓｅｃにおける圧力損失から求めたＰＦ値（１／ｋＰａ）は、好ましくは１０以上、より好ましくは１５以上、更に好ましくは１８以上である。 [PF value]
The PF value is a value indicating the balance between the collection rate and the pressure loss, and is generally used as an index indicating the performance of the filter medium for an air filter, and is represented by the following formula (1).
PF value (1 / kPa)
= -Log 10 {(100-collection rate (%)) / 100} / (pressure loss (Pa) / 1000) (1)
The higher the PF value, the higher the performance as a filter medium for an air filter.
When the fiber aggregate of the present invention is used as a filter medium for an air filter, the PF obtained from the collection rate of particles having a diameter of 0.3 μm at a permeation wind speed of 5.3 m / sec and the pressure loss at a permeation wind speed of 5.3 m / sec. The value (1 / kPa) is preferably 10 or more, more preferably 15 or more, still more preferably 18 or more.
＜用途＞
　本発明の繊維集合体は、上述したように、エアフィルタ用濾材として有用であるが、これに限定されるものではなく、オイルフィルタ用濾材、吸油材、保温材、蓄熱材、断熱材、吸音材等にも応用が期待される。
　なお、本発明の繊維集合体は、その下層（基材）及び上層（被覆材）を有していてもよく、また、他の層と積層してエアフィルタ用濾材等の、上述の種々の用途に適用することができる。 <Use>
As described above, the fiber aggregate of the present invention is useful as a filter medium for an air filter, but is not limited to this, and is not limited to the filter medium for an oil filter, an oil absorbing material, a heat insulating material, a heat storage material, a heat insulating material, and a sound absorbing material. It is expected to be applied to materials.
The fiber aggregate of the present invention may have a lower layer (base material) and an upper layer (coating material) thereof, and may be laminated with other layers to form a filter medium for an air filter or the like. It can be applied to applications.
　以下に実施例と比較例とを挙げて本発明の特徴を更に具体的に説明する。以下の実施例に示す材料、使用量、割合、処理内容、処理手順等は、本発明の趣旨を逸脱しない限り適宜変更することができる。従って、本発明の範囲は以下に示す具体例により限定的に解釈されるべきものではない。なお、実施例及び比較例中の「部」及び「％」は、特に断らない限り、それぞれ「質量部」及び「質量％」を示す。 The features of the present invention will be described in more detail below with reference to Examples and Comparative Examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention should not be construed as limited by the specific examples shown below. Unless otherwise specified, "parts" and "%" in Examples and Comparative Examples indicate "parts by mass" and "% by mass", respectively.
［測定・評価］
＜繊維径の測定＞
〔測定装置〕
　スパッタ：Vacuum　Device　Inc.製、MODEL　MSP-1S　Magnetron　Sputter
　ＳＥＭ：本体＝株式会社キーエンス製　ＶＨＸ－Ｄ５１０
　　　　　測定システム＝株式会社キーエンス製　ＶＨＸ－９５０Ｆ
〔測定方法〕
　測定試料に上記スパッタ装置で金蒸着し、視野に１００本強入る倍率で（２，５００～３，０００倍）１００本以上の繊維径を測定した。得られたデータから、各繊維径の分布を算出した。
　なお、幅約１ｍの繊維集合体について、幅方向に５分割したときの中央部（端から約４０～６０ｃｍ）を試料とした。
－平均繊維径算出方法－
（１）測定値を下記のような階級に分類し、相対度数を求めた。
　　２００ｎｍ未満、２００ｎｍ以上４００ｎｍ未満、４００ｎｍ以上６００ｎｍ未満、６００ｎｍ以上８００ｎｍ未満、８００ｎｍ以上１，０００ｎｍ未満、１μｍ以上２μｍ未満、２μｍ以上３μｍ未満、３μｍ以上５μｍ未満、５μｍ以上１０μｍ未満、１０μｍ以上
（２）各階級の階級値は下記の通りとした。
　　２００ｎｍ未満；階級値＝２００ｎｍ
　　２００ｎｍ以上４００ｎｍ未満；階級値３００ｎｍ
　　４００ｎｍ以上６００ｎｍ未満；階級値５５０ｎｍ
　　６００ｎｍ以上８００ｎｍ未満；階級値７５０ｎｍ
　　８００ｎｍ以上１，０００ｎｍ；階級値８５０ｎｍ
　　１μｍ以上２μｍ未満；階級値１，５００ｎｍ
　　２μｍ以上３μｍ未満；階級値２，５００ｎｍ
　　３μｍ以上５μｍ未満；階級値４，０００ｎｍ
　　５μｍ以上１０μｍ未満；階級値７，５００ｎｍ
　　１０μｍ以上；階級値１０，０００ｎｍ
（３）測定した繊維径の対数平均値を平均繊維径とした。 [Measurement / evaluation]
<Measurement of fiber diameter>
〔measuring device〕
Sputter: Made by Vacuum Device Inc., MODEL MSP-1S Magnetron Sputter
SEM: Main unit = VHX-D510 manufactured by KEYENCE CORPORATION
Measurement system = VHX-950F manufactured by KEYENCE CORPORATION
〔Measuring method〕
Gold was vapor-deposited on the measurement sample with the above sputtering apparatus, and the diameter of 100 or more fibers was measured at a magnification of more than 100 fibers (2,500 to 3,000 times). From the obtained data, the distribution of each fiber diameter was calculated.
The central portion (about 40 to 60 cm from the end) of the fiber aggregate having a width of about 1 m when divided into five in the width direction was used as a sample.
-Average fiber diameter calculation method-
(1) The measured values were classified into the following classes, and the relative frequency was calculated.
Less than 200nm, 200nm or more and less than 400nm, 400nm or more and less than 600nm, 600nm or more and less than 800nm, 800nm or more and less than 1,000nm, 1μm or more and less than 2μm, 2μm or more and less than 3μm, 3μm or more and less than 5μm The class values for each class are as follows.
Less than 200 nm; Class value = 200 nm
200 nm or more and less than 400 nm; class value 300 nm
400 nm or more and less than 600 nm; class value 550 nm
600 nm or more and less than 800 nm; class value 750 nm
800 nm or more 1,000 nm; class value 850 nm
1 μm or more and less than 2 μm; class value 1,500 nm
2 μm or more and less than 3 μm; class value 2,500 nm
3 μm or more and less than 5 μm; class value 4,000 nm
5 μm or more and less than 10 μm; class value 7,500 nm
10 μm or more; class value 10,000 nm
(3) The logarithmic mean value of the measured fiber diameter was taken as the average fiber diameter.
＜厚み＞
　繊維集合体、並びに基材及び被覆材として使用した不織布の厚みは、株式会社ミツトヨ製、シックネスゲージ（５４７－３０１）を使用して測定した。 <Thickness>
The thickness of the fiber aggregate and the non-woven fabric used as the base material and the coating material was measured using a thickness gauge (547-301) manufactured by Mitutoyo Co., Ltd.
　以下の項目については、約１ｍ幅の繊維集合体を、幅方向に５分割し、それぞれについて測定を行い、平均値を求めた。
＜目付＞
　目付は、１０ｃｍ角にカットした試料を精密天秤にて測定し、質量（ｇ）を面積（０．０１ｍ２）で除した値とした。目付については、平均値と共に、ＣＶ値を算出した。
　ＣＶ値（％）＝（目付分布の標準偏差／平均目付）×１００
　なお、基材、繊維集合体、及び被覆材の順で積層してあるエアフィルタ用濾材について目付を測定し、基材及び被覆材の目付を差し引いて、繊維集合体の目付とし、得られた繊維集合体の目付に対して、ＣＶ値を算出した。 For the following items, a fiber aggregate having a width of about 1 m was divided into five in the width direction, and measurements were performed for each to obtain an average value.
<Metsuke>
The basis weight was a value obtained by measuring a sample cut into 10 cm squares with a precision balance and dividing the mass (g) by the area (0.01 m 2). For the basis weight, the CV value was calculated together with the average value.
CV value (%) = (standard deviation of basis weight distribution / average basis weight) x 100
The basis weight of the air filter filter medium laminated in the order of the base material, the fiber aggregate, and the coating material was measured, and the basis weight of the base material and the coating material was subtracted to obtain the basis weight of the fiber aggregate. The CV value was calculated for the basis weight of the fiber aggregate.
＜圧力損失＞
　基材、繊維集合体、及び被覆材の順で積層してあるエアフィルタ用濾材の測定サンプルを、直内径１１３ｍｍ（有効濾材面積１００ｃｍ２）のフィルタホルダにセットし、濾材透過風速を５．３ｃｍ／ｓｅｃになるよう流量計で調整した。そして、この時のサンプル濾材の上下流で生じる圧力損失をマノメータで測定した。なお、測定試料であるエアフィルタ用濾材は、予め、除電処理を行ってから、圧力損失の測定を行った。エアフィルタ用濾材の除電は、ＪＩＳ　Ｂ　９９０８：２０１１「換気用エアフィルタユニット・換気用電気集じん器の性能試験方法」の５．２．３．３ｄ）の２）ＩＰＡ飽和蒸気曝露法に準拠して行った。
　また、基材及び被覆材は、目の粗い不織布から形成されており、圧力損失については、ほとんど影響しない。 <Pressure loss>
A measurement sample of a filter medium for an air filter, which is laminated in the order of a base material, a fiber aggregate, and a coating material, is set in a filter holder having an inner diameter of 113 mm (effective filter medium area 100 cm 2 ), and the filter medium permeation air velocity is 5.3 cm. It was adjusted with a flow meter so that it would be / sec. Then, the pressure loss generated upstream and downstream of the sample filter medium at this time was measured with a manometer. The air filter filter medium, which is the measurement sample, was subjected to static elimination treatment in advance, and then the pressure loss was measured. The static elimination of the filter medium for the air filter complies with JIS B 9908: 2011 "Performance test method for air filter unit for ventilation and electrostatic precipitator for ventilation", 5.2.3.3d) 2) IPA saturated steam exposure method. I went.
Further, the base material and the covering material are formed of a coarse non-woven fabric, and have almost no effect on the pressure loss.
＜捕集効率＞
　圧力損失の測定と同一のフィルタホルダに、測定試料であるエアフィルタ用濾材をセットした後、濾材の上流側に大気塵を導入し、空気を流速５．３ｃｍ／ｓｅｃで通過させたときの０．３μｍ径の上流及び下流の粒子数を、微粒子計測器（ベックマンコールター社製、MET　ONE　HHPC　3+）で測定した。捕集効率は次式で算出した。なお、測定試料であるエアフィルタ用濾材は、予め、除電処理を行ってから、捕集効率の測定を行った。エアフィルタ用濾材の除電は、ＪＩＳ　Ｂ　９９０８：２０１１「換気用エアフィルタユニット・換気用電気集じん器の性能試験方法」の５．２．３．３ｄ）の２）ＩＰＡ飽和蒸気曝露法に準拠して行った。
　捕集効率（％）＝（１－（ＣＯ／ＣＩ））×１００
　　　ＣＯ＝下流側０．３μｍ粒子の粒子数
　　　ＣＩ＝上流側０．３μｍ粒子の粒子数
　なお、基材及び被覆材は、目の粗い不織布から形成されており、捕集効率については、ほとんど影響しない。 <Collection efficiency>
After setting the filter medium for the air filter, which is the measurement sample, in the same filter holder as the measurement of pressure loss, air dust is introduced to the upstream side of the filter medium, and 0 when air is passed at a flow velocity of 5.3 cm / sec. The number of particles upstream and downstream with a diameter of 3 μm was measured with a fine particle measuring instrument (MET ONE HHPC 3+ manufactured by Beckman Coulter). The collection efficiency was calculated by the following formula. The air filter filter medium, which is the measurement sample, was subjected to static elimination treatment in advance, and then the collection efficiency was measured. The static elimination of the filter medium for the air filter complies with JIS B 9908: 2011 "Performance test method for air filter unit for ventilation and electrostatic precipitator for ventilation", 5.2.3.3d) 2) IPA saturated steam exposure method. I went.
Collection efficiency (%) = (1- (CO / CI)) x 100
CO = Number of particles of 0.3 μm particles on the downstream side CI = Number of particles of 0.3 μm particles on the upstream side The base material and coating material are formed of a coarse non-woven fabric and have almost no effect on the collection efficiency. ..
＜ＰＦ値＞
　上記で求めた圧力損失及び捕集効率（粒子径０．３μｍの粒子の捕集効率）から、次式に従いＰＦ値を求めた。ＰＦ値はエアフィルタ用濾材の捕集性能と圧損のバランスを示す指標として従来から使用されている値であり、性能がよいほどＰＦ値が大きくなる。
　ＰＦ値（１／ｋＰａ）
　　＝{-log((100-捕集効率(%))/100)}/(圧力損失(Pa)/1000) <PF value>
From the pressure loss and collection efficiency (collection efficiency of particles having a particle size of 0.3 μm) obtained above, the PF value was calculated according to the following equation. The PF value is a value conventionally used as an index showing the balance between the collection performance and the pressure loss of the filter medium for an air filter, and the better the performance, the larger the PF value.
PF value (1 / kPa)
= {-Log ((100-collection efficiency (%)) / 100)} / (pressure loss (Pa) / 1000)
［繊維集合体の製造］
　図１に示すメルトブロー装置を使用し、単孔吐出量（１孔あたりの吐出量）、エアノズル２５の１孔あたりの吐出風量（Ｌ／ｍｉｎ）、エアノズル２５からの吐出温度（℃）、繊維集合体の厚みを表１に記載のように変更して、繊維集合体を作製し、上述の方法により、得られた繊維集合体について、測定及び評価を行った。
　なお、製造時には、スパンボンド不織布（ポリエステル製、目付＝１２ｇ／ｍ２、三井化学株式会社製、Ｒ００４、厚み＝０．１３ｍｍ）を基材として使用し、ポリエチレンテレフタレート長繊維不織布（目付＝２５ｇ／ｍ２、旭化成工業株式会社製、Ｅ１０２５、厚み＝０．１５ｍｍ）を被覆材として使用した。
　結果を以下の表１に示す。 [Manufacturing of fiber aggregates]
Using the melt blow device shown in FIG. 1, the single-hole discharge amount (discharge amount per hole), the discharge air amount per hole of the air nozzle 25 (L / min), the discharge temperature from the air nozzle 25 (° C.), and the fiber assembly. The thickness of the body was changed as shown in Table 1 to prepare a fiber aggregate, and the obtained fiber aggregate was measured and evaluated by the above method.
At the time of manufacture, a spunbonded non-woven fabric (polyester , grain = 12 g / m 2 , manufactured by Mitsui Chemicals, Inc., R004, thickness = 0.13 mm) is used as a base material, and a polyethylene terephthalate long fiber non-woven fabric (grain = 25 g / m / m 2 , manufactured by Asahi Kasei Kogyo Co., Ltd., E1025, thickness = 0.15 mm) was used as the coating material.
The results are shown in Table 1 below.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　表１に示されているように実施例の繊維集合体では、捕集効率が６０％以上であり、圧損（圧力損失）が３２Ｐａ以下であり、更に、ＰＦ値が１５．０以上であった。
　一方、比較例１のように、１μｍ以上２μｍ未満の繊維の含有率が１０％未満の場合には、細い繊維が多く、圧力損失が大きくなった。また、１μｍ以上２μｍ未満の繊維の含有率が５０％以上の比較例２では、十分な捕集率（捕集効率）が得られなかった。
　更に、平均繊維径が６００ｎｍ未満である比較例３では、細い繊維が多いため、圧力損失が大きくなった。また、１μｍ以上２μｍ未満の繊維の含有率が１０％未満であり、また、平均繊維径が比較的小さい比較例４では、圧損が高く、また、十分なＰＦ値を得ることができなかった。 As shown in Table 1, in the fiber aggregate of the example, the collection efficiency was 60% or more, the pressure loss (pressure loss) was 32 Pa or less, and the PF value was 15.0 or more. ..
On the other hand, when the content of the fibers of 1 μm or more and less than 2 μm was less than 10% as in Comparative Example 1, there were many fine fibers and the pressure loss was large. Further, in Comparative Example 2 in which the content of fibers of 1 μm or more and less than 2 μm was 50% or more, a sufficient collection rate (collection efficiency) could not be obtained.
Further, in Comparative Example 3 in which the average fiber diameter is less than 600 nm, the pressure loss is large because there are many fine fibers. Further, in Comparative Example 4 in which the content of fibers of 1 μm or more and less than 2 μm was less than 10% and the average fiber diameter was relatively small, the pressure loss was high and a sufficient PF value could not be obtained.
　本発明の繊維集合体は、エアフィルタ用濾材として好適に使用され、エアフィルタ用濾材をはじめとする、種々の不織布用途、例えば、オイルフィルタ用濾材、吸油材、吸音材、保温材、断熱材等への応用が期待される。 The fiber aggregate of the present invention is suitably used as a filter medium for an air filter, and is used for various non-woven fabrics such as a filter medium for an air filter, for example, a filter medium for an oil filter, an oil absorbing material, a sound absorbing material, a heat insulating material, and a heat insulating material. It is expected to be applied to such applications.
　１：メルトブロー装置
　１０：樹脂供給部
　１１：ホッパ
　１２：押出機
　１３：ダイ
　１４：樹脂ノズル
　２０：空気流発生部
　２１：コンプレッサ
　２２：配管
　２３：レギュレータ
　２４：ヒータ
　２５：エアノズル
　３０：捕集部
　３１：サクションドラム
　３２：ブロワ
　３３：吸引部
　３４，３５：不織布ロール
　３６：巻取りドラム
　４０：過熱蒸気供給部
　４１：加熱器
　４２：配管
　４３：過熱蒸気ノズル
　５１：不織布（基材）
　５２：不織布（被覆材（カバー材）） 1: Melt blow device 10: Resin supply unit 11: Hopper 12: Extruder 13: Die 14: Resin nozzle 20: Air flow generator 21: Compressor 22: Piping 23: Regulator 24: Heater 25: Air nozzle 30: Collection unit 31 : Suction drum 32: Blower 33: Suction part 34, 35: Non-woven fabric roll 36: Winding drum 40: Superheated steam supply part 41: Heater 42: Piping 43: Superheated steam nozzle 51: Non-woven fabric (base material)
52: Non-woven fabric (covering material (covering material))

Claims (11)

  1. 　繊維集合体を構成する繊維の平均繊維径が６００ｎｍ以上１５００ｎｍ以下であり、
    　繊維径１μｍ以上２μｍ未満の繊維の含有率が１０％以上５０％以下であり、
    　繊維集合体を構成する繊維が、熱可塑性樹脂を主成分として含む、
    　繊維集合体。     The average fiber diameter of the fibers constituting the fiber aggregate is 600 nm or more and 1500 nm or less.
    The content of fibers having a fiber diameter of 1 μm or more and less than 2 μm is 10% or more and 50% or less.
    The fibers constituting the fiber aggregate contain a thermoplastic resin as a main component.
    Fiber aggregate.
  2. 　繊維径が４００ｎｍ以上１０００ｎｍ未満の繊維を３５％以上含有する、請求項１に記載の繊維集合体。 The fiber aggregate according to claim 1, which contains 35% or more of fibers having a fiber diameter of 400 nm or more and less than 1000 nm.
  3. 　繊維径が２μｍ以上の繊維の含有率が２０％以下である、請求項１又は２に記載の繊維集合体。 The fiber aggregate according to claim 1 or 2, wherein the content of fibers having a fiber diameter of 2 μm or more is 20% or less.
  4. 　繊維径が４００ｎｍ以上６００ｎｍ未満の繊維の含有率が５％以上４０％以下である、請求項１～３のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 3, wherein the content of fibers having a fiber diameter of 400 nm or more and less than 600 nm is 5% or more and 40% or less.
  5. 　繊維径が６００ｎｍ以上８００ｎｍ未満の繊維の含有率が５％以上４０％以下である、請求項１～４のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 4, wherein the content of fibers having a fiber diameter of 600 nm or more and less than 800 nm is 5% or more and 40% or less.
  6. 　繊維径が８００ｎｍ以上１０００ｎｍ未満の繊維の含有率が５％以上４０％以下である、請求項１～５のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 5, wherein the content of fibers having a fiber diameter of 800 nm or more and less than 1000 nm is 5% or more and 40% or less.
  7. 　繊維径が４００ｎｍ未満の繊維の含有率が２０％以下である、請求項１～６のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 6, wherein the content of fibers having a fiber diameter of less than 400 nm is 20% or less.
  8. 　前記繊維集合体が、乾式の繊維集合体である、請求項１～７のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 7, wherein the fiber aggregate is a dry type fiber aggregate.
  9. 　前記熱可塑性樹脂が、ポリオレフィン樹脂及びポリエステル樹脂から選択される少なくとも１つである、請求項１～８のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 8, wherein the thermoplastic resin is at least one selected from a polyolefin resin and a polyester resin.
  10. 　前記熱可塑性樹脂が、ポリプロピレン及びポリブチレンテレフタレートから選択される少なくとも１つである、請求項１～９のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 9, wherein the thermoplastic resin is at least one selected from polypropylene and polybutylene terephthalate.
  11. 　前記繊維集合体の坪量のＣＶ値が２０％以下である、請求項１～１０のいずれかに記載の繊維集合体。 The fiber aggregate according to any one of claims 1 to 10, wherein the CV value of the basis weight of the fiber aggregate is 20% or less.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012102398A1 (en) * 2011-01-28 2012-08-02 タピルス株式会社 Melt-blown nonwoven fabric comprising ultra-fine fibers, production method therefor, and device for producing same
WO2016148174A1 (en) * 2015-03-16 2016-09-22 東レ・ファインケミカル株式会社 Nonwoven fabric and method for manufacturing same

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58186412A (en) * 1982-04-26 1983-10-31 Asahi Chem Ind Co Ltd Filter medium
JP2849291B2 (en) * 1992-10-19 1999-01-20 三井化学株式会社 Electretized nonwoven fabric and method for producing the same
JPH10280267A (en) * 1997-04-08 1998-10-20 Mitsui Chem Inc Flexible spun-bonded nonwoven fabric
JP2004270096A (en) * 2003-03-11 2004-09-30 Toray Ind Inc Filament nonwoven fabric and method for producing the same
JP2015190081A (en) * 2014-03-28 2015-11-02 旭化成せんい株式会社 Melt-blown nonwoven fabric
KR102477321B1 (en) * 2015-07-24 2022-12-13 주식회사 쿠라레 Fiber laminate
JP6210422B2 (en) * 2015-12-21 2017-10-11 パナソニックＩｐマネジメント株式会社 Fiber assembly
EP3255188B1 (en) * 2016-06-06 2019-08-07 Borealis AG Melt blown web with good water barrier properties

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012102398A1 (en) * 2011-01-28 2012-08-02 タピルス株式会社 Melt-blown nonwoven fabric comprising ultra-fine fibers, production method therefor, and device for producing same
WO2016148174A1 (en) * 2015-03-16 2016-09-22 東レ・ファインケミカル株式会社 Nonwoven fabric and method for manufacturing same

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