Search

CN-121976396-A - Method and apparatus for manufacturing electrostatic electret fibers and electret product

CN121976396ACN 121976396 ACN121976396 ACN 121976396ACN-121976396-A

Abstract

The invention relates to a method for producing electrostatic electret fibers, in particular for producing electret fiber formations, in which method fibers are produced from synthetic and/or natural materials, a polar liquid is atomized by means of a gaseous pressure medium to produce a process aerosol, the fibers are treated with the process aerosol for electrostatic electret, wherein the atomization is carried out at a quotient of a polar liquid volume flow per liter per hour and an overpressure of the gaseous pressure medium in millibars of 0.004 to 0.008.

Inventors

  • F. Knabe
  • R milis
  • R. Berkman

Assignees

  • 欧瑞康纺织有限及两合公司

Dates

Publication Date
20260505
Application Date
20230302
Priority Date
20220304

Claims (15)

  1. 1. A method for manufacturing an electrostatic electret fiber (12), in particular for manufacturing an electret fiber formation (14), in which method, Producing fibers (12) from synthetic and/or natural materials, Atomizing a polar liquid by means of a gaseous pressure medium to produce a process aerosol (24), Treating the fibers (12) with a treatment aerosol (24) for electrostatic electret, Wherein the atomization is carried out with a quotient of the volume flow of the polar liquid in liters per hour and the overpressure of the gaseous pressure medium in millibars of 0.004 to 0.008.
  2. 2. A method for manufacturing an electrostatic electret fiber (12), in particular according to claim 1, in which method, Producing fibers (12) from synthetic and/or natural materials, Atomizing a polar liquid by means of a gaseous pressure medium to produce a process aerosol (24), Treating the fibers (12) with a treatment aerosol (24) for electrostatic electret, Wherein the atomization is carried out with a quotient of the polar liquid mass flow and the gaseous pressure medium mass flow of 1.4 to 3.
  3. 3. A method for manufacturing an electrostatic electret fiber (12), in particular according to any of the preceding claims, in which method, -Making fibres (12) from synthetic and/or natural materials, Atomizing a polar liquid by means of a gaseous pressure medium to produce a process aerosol (24), Treating the fibers (12) with a treatment aerosol (24) for electrostatic electret, Wherein the atomization is carried out with a quotient of the polar liquid volume flow and the gaseous pressure medium volume flow of 0.001 to 0.004.
  4. 4. The method according to any of the preceding claims, characterized in that the atomizing of the polar liquid is performed by at least one two-component nozzle (48), in particular by a plurality of two-component nozzles (48).
  5. 5. The method according to claim 4, characterized in that the atomizing is carried out in one two-component nozzle (48) or for each two-component nozzle (48) with a polar liquid volume flow of 3.2 liters per hour to 5.2 liters per hour, in particular with a polar liquid volume flow of 4.2 liters per hour or about 4.2 liters per hour.
  6. 6. The method according to any of the preceding claims, characterized in that the atomizing of the polar liquid is carried out at an overpressure of 500 mbar to 900 mbar of gaseous pressure medium, in particular at 700 mbar or about 700 mbar of gaseous pressure medium.
  7. 7. The method according to any one of claims 4 to 6, characterized in that in one two-component nozzle (48) or for each two-component nozzle (48) atomization is carried out with a gaseous pressure medium mass flow of 2.1 kg per hour to 2.7 kg per hour, in particular with a polar liquid mass flow of 2.1 kg per hour to 2.5 kg per hour or 2.3 kg per hour to 2.7 kg per hour.
  8. 8. The method according to any one of claims 4 to 7, characterized in that in one two-component nozzle (48) or for each two-component nozzle (48) atomization is carried out with a gaseous pressure medium volume flow of 1.5 to 2.5 cubic meters per hour, in particular with a polar liquid volume flow of 0.002 to 0.008 cubic meters per hour.
  9. 9. The method according to any of the preceding claims, characterized in that the fibers (12) are sprayed with a treatment aerosol (24) before integration into the fiber formation (14) and/or the fiber nonwoven and/or before laying on the collecting device (28) and/or before being captured by a vacuum source.
  10. 10. The method according to any of the preceding claims, characterized in that the fibers (12) are produced by a melt-blowing process and/or the fibers (12) are sprayed with the process aerosol (24) directly after the fibers exit the melt-blowing nozzle device (20) and/or the process aerosol (24) is fed into the outlet mouth of the melt-blowing nozzle device (20) for spraying the fibers (12).
  11. 11. The method according to any of the preceding claims, characterized in that the fibers (12) are integrated into a fiber formation (14) and/or a fiber nonwoven and/or are laid on a collecting device (28) after spraying with a process aerosol (24), and/or the fibers (12) integrated into a fiber formation (14) and/or a fiber nonwoven and/or are laid on a collecting device (28) have a residual moisture of less than 6%, in particular less than 5%, without active drying.
  12. 12. Apparatus (10) for manufacturing an electrostatic electret fiber (12), in particular for performing the method according to any one of the preceding claims, having -A spinning device (16) for producing fibres (12) from synthetic and/or natural material, and A nozzle device (22) for generating a treatment aerosol (24) by atomizing a polar liquid by means of a gaseous pressure medium and for electrostatically electret the fibers (12) by spraying the fibers (12) with the treatment aerosol (24), -Wherein the nozzle device (22) is set to perform the atomizing in case the quotient of the polar liquid volume flow rate per hour and the overpressure of the gaseous pressure medium in millibar is 0.004 to 0.008, and/or in case the quotient of the polar liquid mass flow rate and the gaseous pressure medium mass flow rate is 1.4 to 3, and/or in case the quotient of the polar liquid volume flow rate and the gaseous pressure medium volume flow rate is 0.001 to 0.004.
  13. 13. The device (10) according to claim 12, characterized in that the nozzle arrangement (22) has one two-component nozzle (48) or a plurality of two-component nozzles (48), wherein the plurality of two-component nozzles (48) are preferably arranged at a distance of 4 to 10cm, in particular a distance of 5 to 8cm, or a distance of 7cm or about 7cm from each other, and/or the openings of the two-component nozzles (48) are arranged at an angle (52), in particular at an angle (52) of 1 ° to 30 °, preferably 5 ° to 20 °, relative to the horizontal line (50).
  14. 14. The apparatus (10) according to claim 12 or 13, characterized in that the spinning device (16) is configured as a melt-blowing device, a melt-spinning device, or a solvent-spinning device, in particular having Exxon nozzles or one or more rows of coaxial nozzles or nonwoven nozzles.
  15. 15. Electret product, in particular electret fiber and/or electret fiber nonwoven fabric, manufactured with a method according to any one of claims 1 to 12 and/or by an apparatus (10) according to any one of claims 12 to 14.

Description

Method and apparatus for manufacturing electrostatic electret fibers and electret product The present application is a divisional application of patent application No. 202310191560.9, filed on 2/3/2023, entitled "method and apparatus for manufacturing electrostatic electret fibers" and electret product. Technical Field The present invention relates to a method for manufacturing electrostatic electret fibers, in particular for manufacturing electret fiber forms/fiber structures. The invention further relates to a device for producing electrostatic electret fibers, in particular for producing electret fiber formations. Finally, the invention relates to an electret product, in particular an electret fiber and/or electret fiber nonwoven fabric. Background The charge/electrostatic electret can be applied electrostatically to the fibers or to a formation produced with such fibers by means of so-called water-electret. Such electrostatic electret may for example have an advantageous effect on the filtration properties of the fiber formation. In so-called water-stationary electrodes, aerosols and/or vapors are generated from polar liquids and, under defined operating conditions, release charges deposited on fibrous materials, for example nonwoven fabrics or fibers made of polymers. The charge can be anchored semi-permanently by the additive to the corresponding fibre surface and thus the filtering effect of such fibre material is improved. But the water resident is accompanied by wetting of the corresponding fibers or corresponding fiber formations. This wetting may lead to corrosion and mildew in subsequent processing steps. To avoid this effect of wetting, active drying of the fibers or fiber formations is provided. However, such active drying increases the production effort and also the complexity of the production facilities used for this purpose. Furthermore, active drying is accompanied by a higher energy requirement, as this additionally increases the production costs. Disclosure of Invention Against the background of the above-described background, the object of the present invention is to provide a method for producing electrostatic electret fibers, which can be carried out with high operational safety and with a resultant high product quality and at the same time with lower production costs and energy consumption. The object of the invention is also to provide an apparatus for manufacturing electrostatic electret fibers and an electret product. In terms of the method, this object is achieved by the subject matter of claims 1,2 and 3, respectively. The device according to the invention is the subject of claim 13 and the electret product according to the invention is given in claim 15. Advantageous embodiments are given in the dependent claims. A first aspect of the invention relates to a method for manufacturing electrostatic electret fibers, in particular for manufacturing electret fiber formations, in which method fibers are manufactured from synthetic and/or natural materials, a polar liquid is atomized by means of a gaseous pressure medium to produce a process aerosol, and the fibers are treated with the process aerosol for electrostatic electret. According to the invention, the atomization is carried out here at a quotient of the polar liquid volume flow (unit liter/hr) and the overpressure of the gaseous pressure medium (unit mbar) of 0.004 to 0.008. Thus, according to the invention, the atomization is carried out in a ratio of 0.004 to 0.008 of the volume flow of the polar liquid (unit liter/hour) to the overpressure of the gaseous pressure medium (unit mbar). By means of this quotient or this ratio, on the one hand, a relatively large charge quantity can be produced and applied to the respective fibers. At the same time, by means of such quotient or such ratio, the amount of treatment aerosol produced can be sufficiently limited or kept small. In this way, it is ensured that only relatively little of the fibers or fiber formations are wetted. Active drying of the electrostatic electret fibers can thus be avoided and the production effort and the energy consumption required for production can thus be significantly reduced. At the same time, a high filtering action of the fiber formation produced from the fibers thus produced is ensured due to the sufficient electrostatic electret. In a preferred manner, the overpressure of the gaseous pressure medium can be an overpressure relative to the ambient pressure. The overpressure of the gaseous pressure medium can thus be related to the pressure difference of the pressure of the gaseous pressure medium with respect to the ambient pressure. By means of the overpressure relative to the ambient pressure, atomization can be carried out in a particularly advantageous manner and with high operational safety. The overpressure of the gaseous pressure medium can likewise be absolute pressure. Absolute pressure is understood to be the pressure relative to a reference