Classifications

• • 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
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/736—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged characterised by the apparatus for arranging fibres
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/08—Melt spinning methods
  • D01D5/098—Melt spinning methods with simultaneous stretching
  • D01D5/0985—Melt spinning methods with simultaneous stretching by means of a flowing gas (e.g. melt-blowing)
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
  • B29C48/05—Filamentary, e.g. strands
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
  • B29C48/07—Flat, e.g. panels
  • B29C48/08—Flat, e.g. panels flexible, e.g. films
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/14—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration
  • B29C48/142—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration using force fields, e.g. gravity or electrical fields
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/30—Extrusion nozzles or dies
  • B29C48/345—Extrusion nozzles comprising two or more adjacently arranged ports, for simultaneously extruding multiple strands, e.g. for pelletising
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D4/00—Spinnerette packs; Cleaning thereof
• • 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
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/724—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged forming webs during fibre formation, e.g. flash-spinning
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C2948/00—Indexing scheme relating to extrusion moulding
  • B29C2948/92—Measuring, controlling or regulating
  • B29C2948/92504—Controlled parameter
  • B29C2948/92609—Dimensions
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C2948/00—Indexing scheme relating to extrusion moulding
  • B29C2948/92—Measuring, controlling or regulating
  • B29C2948/92819—Location or phase of control
  • B29C2948/92933—Conveying, transporting or storage of articles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/001—Combinations of extrusion moulding with other shaping operations
  • B29C48/0021—Combinations of extrusion moulding with other shaping operations combined with joining, lining or laminating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/14—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration
  • B29C48/147—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration after the die nozzle
  • B29C48/1472—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration after the die nozzle at the die nozzle exit zone
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/355—Conveyors for extruded articles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/92—Measuring, controlling or regulating

Definitions

• the present disclosure relates generally to making webs of nonwoven media, and, more particularly, to a method and apparatus for making such webs of nonwoven media.
• meltblown media has come into wide commercial use, for uses such as filtration, cleaning wipes, bandages, surgical drapes, battery electrode separation and insulation.
• meltblowing die of a particular width will provide useful media of a lesser width at the collector. This is especially noticeable when the collector is positioned more than 40 cm from the meltblowing die. For example, a 200 cm wide die may produce usable webs having a width of only 175 cm.
• the present disclosure generally provides a method and apparatus for forming a meltblown web by positioning a Coanda effect device adjacent to the flight path of the fibers emerging from the blowing die on at least one edge of the web. While not wishing to be bound by any theory, it is believed that the Coanda effect provided by the Coanda effect device redirects some of the fibers which would otherwise form an insufficiently thick "ragged edge" on the web formed on the collector.
• the present disclosure provides a meltblowing apparatus, comprising a meltblowing die having a plurality of filament outlets, a collector for receiving filaments of polymeric material expelled from the filament outlets, and a first Coanda effect device positioned adjacent to the path of the filaments adjacent to the last filament outlet at an end of the meltb lowing die.
• the present disclosure provides a method of forming a meltblown media, comprising providing a meltblowing die having a plurality of filament outlets, positioning a first Coanda effect device adjacent to a first end of the meltblowing die, expelling molten filaments from a meltblowing die, manipulating the flight of the molten filaments with the first Coanda effect device, and collecting the molten filaments to form a web of nonwoven media.
• One advantage of webs formed using the apparatus and method of the present disclosure is that they have more uniform side-to-side basis weights compared to webs made according to conventional techniques. That is, the basis weight of the side edge regions of webs produced using the apparatus and methods described herein are similar to, and consistent with, the basis weight of the central region of the web located between the side edge regions.
• FIG. 1 is a schematic view of a meltblowing apparatus without the inventive features.
• FIG. 2 is a perspective view of one end of a meltblowing die generally as depicted in FIG. 1, except that certain inventive features have been added.
• FIG. 3 is a perspective view of a Coanda effect device according to the invention in isolation.
• FIG. 4 is a plan view of the Coanda effect device of FIG. 3. Repeated use of reference characters in the specification and drawings is intended to represent the same or analogous features or elements of the disclosure.
• FIG. 1 a schematic view of a meltblowing apparatus 20 is illustrated without the inventive features for background and the establishment of nomenclature.
• a meltblowing apparatus 20 including a meltblowing die 22 is illustrated in a diagrammatic cross-section.
• the meltblowing die 22 is used to expel a stream 24 of extended polymeric filaments towards a collection belt 26 moving in direction "D," is illustrated.
• a belt is depicted in connection with this embodiment, those acquainted with the meltblowing art will understand that other collectors, such as a rotating drum, may be used for the purpose of collecting, conveying, and taking off the filaments as media.
• the meltblowing die 22 is provided with cavities 28 and 30 for directing two streams of heated gas against the stream 24 of polymeric filaments just after the stream 24 has been extruded from a line of extrusion orifices 32.
• the heated gas jets emerging from cavities 28 and 30 extend and thin the filaments emerging from the extrusion orifices 32 so that the filaments have the proper size and dispersion to form the desired media 34 upon the collector 26.
• the meltblowing apparatus 20 further includes a pair of ducts 40 and 42, one upstream and one downstream of the stream 24 compared to the direction "D". Secondary flow is expelled from ducts 40 and 42 against the filament stream 24 so the filaments, when they impinge upon the collection belt 26, have the properties desired in the media 34.
• the foregoing description generally corresponds to the disclosure of coassigned U.S. Pat. No. 6,861,025 to Breister et al, and is adequate for the production of meltblown media at low and moderate speeds of collector 26.
• additional manifolds 44 and 46 may be provided for the purpose of disrupting standing vortices.
• FIG. 2 a perspective view of one end of the meltblowing die 22 including certain inventive features is illustrated. Specifically, a first Coanda effect device
• the Coanda effect device 50 is positioned adjacent to the path of the filaments emerging from the last orifice 32a at an end of the meltblowing die 22.
• the Coanda effect device 50 generally comprises a convex surface arranged along the direction of the filament flow path.
• the convex surface flares outwardly away from the array of orifices 32 in the direction away from the meltb lowing die 22.
• the convex surface serves to alter, or can be used to adjust or control, the flow path of the filaments in the region adjacent to the Coanda effect device 50, thereby producing a web of media having a more consistent and uniform basis weight across its entire width.
• a shield 52 is positioned between the lateral end of the array of orifices 32 and the first Coanda effect device 50.
• the shield 52 is positioned to direct and regulate the entrainment of ambient air from the side of the die 22 towards the leading edge 54 of the first Coanda effect device 50. It will be recognized that a second Coanda effect device and a second shield may optionally be provided at the other end of the array of orifices 32.
• FIGS. 3 and 4 there is shown a perspective view and a plan view, respectively, of a Coanda effect device 50 shown in isolation.
• the Coanda effect device 50 has a leading edge 54 and a trailing edge 56.
• the exact parameters of an advantageous Coanda effect device will vary depending on the material being extruded from the orifices 32 and other process parameters. However, some general observations for achieving desirable results have been made.
• the Coanda effect device may be characterized in terms of a first radius of curvature "Rl" adjacent to the leading edge 54, a second radius of curvature “R2" adjacent to the trailing edge 56, and/or an angle of attack a.
• the angle of attack a can be defined generally as the angle between the surface of the Coanda effect device and a line generally parallel to the streamlines of material 24 emerging from the orifices 32.
• the first Rl and second R2 radii of curvature and the angle of attack a should be selected so as to minimize vortex shedding at the trailing edge 56.
• the angle of attack a may be less than about 45 degrees, less than about 35 degrees, or less than 25 degrees. Negative angles of attack are less commonly indicated, but not considered to be outside the scope of the invention.
• the first radius of curvature Rl may be at least about 4 cm, at least about 6 cm or at least about 7.5, and no greater than about 24 cm, no greater than about 20 cm, or no greater than about 18 cm.
• the second radius of curvature R2 may be at least about 14 cm, at least about 16 cm, or at least about 18 cm.
• the Coanda effect device may have a uniform cross section, but this is not considered essential. Also, in embodiments where two Coanda effect devices are provided, it may be desirable that the first and second Coanda effect devices be similar or even identical, but this is not considered essential.
• the Coanda effect devices may optionally include mechanical expedients such as cams, levers, bolts or the like so that minor adjustments to the radii of curvature and/or angle of attack can be made to the Coanda effect device during, for example, the production of meltblown media.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Textile Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
• Nonwoven Fabrics (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (2)

Family

ID=46965483

Family Applications (1)

Country Status (7)

Family Cites Families (7)

• 2012
  • 2012-04-06 EP EP12768658.2A patent/EP2699720A4/en not_active Withdrawn
  • 2012-04-06 KR KR1020137028912A patent/KR20140020315A/ko not_active Withdrawn
  • 2012-04-06 BR BR112013025726A patent/BR112013025726A2/pt not_active IP Right Cessation
  • 2012-04-06 JP JP2014504017A patent/JP2014514472A/ja active Pending
  • 2012-04-06 CN CN201280021758.2A patent/CN103518012A/zh active Pending
  • 2012-04-06 WO PCT/US2012/032481 patent/WO2012138970A2/en not_active Ceased
  • 2012-04-06 US US13/441,338 patent/US20120256357A1/en not_active Abandoned

Non-Patent Citations (1)

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