EP1230863B1 - Poröses Element - Google Patents

Poröses Element Download PDF

Info

Publication number
EP1230863B1
EP1230863B1 EP02076724A EP02076724A EP1230863B1 EP 1230863 B1 EP1230863 B1 EP 1230863B1 EP 02076724 A EP02076724 A EP 02076724A EP 02076724 A EP02076724 A EP 02076724A EP 1230863 B1 EP1230863 B1 EP 1230863B1
Authority
EP
European Patent Office
Prior art keywords
fibers
sheath
core
bicomponent fibers
porous
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP02076724A
Other languages
English (en)
French (fr)
Other versions
EP1230863A3 (de
EP1230863A2 (de
Inventor
Richard M. Berger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Filtrona Richmond Inc
Original Assignee
Filtrona Richmond Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US08/470,594 external-priority patent/US5607766A/en
Application filed by Filtrona Richmond Inc filed Critical Filtrona Richmond Inc
Publication of EP1230863A2 publication Critical patent/EP1230863A2/de
Publication of EP1230863A3 publication Critical patent/EP1230863A3/de
Application granted granted Critical
Publication of EP1230863B1 publication Critical patent/EP1230863B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
    • A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
    • A24D3/06—Use of materials for tobacco smoke filters
    • A24D3/062—Use of materials for tobacco smoke filters characterised by structural features
    • A24D3/063—Use of materials for tobacco smoke filters characterised by structural features of the fibers
    • A24D3/064—Use of materials for tobacco smoke filters characterised by structural features of the fibers having non-circular cross-section
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
    • A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
    • A24D3/06—Use of materials for tobacco smoke filters
    • A24D3/062—Use of materials for tobacco smoke filters characterised by structural features
    • A24D3/063—Use of materials for tobacco smoke filters characterised by structural features of the fibers
    • A24D3/065—Use of materials for tobacco smoke filters characterised by structural features of the fibers with sheath/core of bi-component type structure
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
    • A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
    • A24D3/06—Use of materials for tobacco smoke filters
    • A24D3/08—Use of materials for tobacco smoke filters of organic materials as carrier or major constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
    • B43K—IMPLEMENTS FOR WRITING OR DRAWING
    • B43K1/00—Nibs; Writing-points
    • B43K1/003—Capillary nibs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
    • B43K—IMPLEMENTS FOR WRITING OR DRAWING
    • B43K15/00—Assembling, finishing, or repairing pens
    • B43K15/02—Automatic machines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
    • B43K—IMPLEMENTS FOR WRITING OR DRAWING
    • B43K8/00—Pens with writing-points other than nibs or balls
    • B43K8/02—Pens with writing-points other than nibs or balls with writing-points comprising fibres, felt, or similar porous or capillary material
    • B43K8/03—Ink reservoirs; Ink cartridges
    • 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
    • D01D5/253—Formation of filaments, threads, or the like with a non-circular cross section; Spinnerette packs therefor
    • 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
    • D01D5/28—Formation of filaments, threads, or the like while mixing different spinning solutions or melts during the spinning operation; Spinnerette packs therefor
    • D01D5/30—Conjugate filaments; Spinnerette packs therefor
    • D01D5/34—Core-skin structure; Spinnerette packs therefor
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F8/00—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
    • D01F8/04—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers
    • D01F8/06—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers with at least one polyolefin as constituent
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F8/00—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
    • D01F8/04—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers
    • D01F8/14—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers with at least one polyester as constituent
    • 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
    • D04H3/02—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of forming fleeces or layers, e.g. reorientation of yarns or filaments
    • D04H3/03—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of forming fleeces or layers, e.g. reorientation of yarns or filaments at random
    • 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
    • D04H3/08—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating
    • D04H3/16—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating with bonds between thermoplastic filaments produced in association with filament formation, e.g. immediately following extrusion

Definitions

  • This invention relates to a porous element comprising polymeric bicomponent fibers and to its production.
  • EP-B-0881889 from whose Application 96919167.5 the present application is divided, is direct to continuous bicomponent fibers comprising a core of thermoplastic polymer material substantially totally surrounded by a sheath of polymer material selected from polyethylene terephthalate and copolymers thereof, said sheath polymer material being of higher melting point than said core polymer material and said fibers, on average, having a diameter of 12 microns or less.
  • the invention provides a substantially self-sustaining, three-dimensional, porous element formed of a web or roving of flexible thermoplastic fibrous material comprising an interconnecting network of highly dispersed continuous fibers randomly oriented primarily in a longitudinal direction and bonded to each other at points of contact, wherein at least a major part of said continuous fibers are bicomponent fibers comprising a core of thermoplastic polymer material substantially totally surrounded by a sheath of polymer material selected from polyethylene terephthalate and copolymers thereof, said sheath material being of higher melting point than said core material; preferably said bicomponent fibers, on average, have a diameter of about 12 microns or less.
  • the invention also provides a method of making a substantially self -sustaining elongated porous element comprising: [a] providing separate sources of a molten sheath-forming material selected from polyethylene terephthalate and copolymers thereof and of a molten core-forming thermoplastic material; [b] continuously extruding said molten core-forming and sheath-forming materials through a multiplicity of openings in a conjugate sheath-core die to provide a multiplicity of bicomponent fibers, each fiber comprising a continuous core of said core-forming material substantially totally surrounded by a sheath of said sheath-forming material; [c] collecting said bicomponent fibers on a continuously moving surface to form a highly entangled web or roving of said bicomponent fibers in the form of an interconnecting network of highly dispersed continuous fibers randomly oriented primarily in the direction of movement of said moving surface; [d] gathering said web or roving of bicomponent fibers; [e] heating said gathered web or
  • the method may include one or more of the steps of [i] continuously forming a longitudinal recess in said porous element along the periphery thereof; [ii] continuously covering said porous element with an outer sheath prior to cutting the same into discrete lengths; [iii] continuously overwrapping said porous element with a strip material to form an outer sheath; and [iv] forming said porous element as a rod and wrapping said porous rod with a filter tipping material prior to cutting the same into discrete lengths.
  • the method of the invention can include production of "sheath-core" bicomponent fibers wherein a sheath of polyethylene terephthalate or a copolymer thereof is spun to completely cover and encompass a core of relatively low cost, low shrinkage, high strength thermoplastic polymeric material such as polypropylene or polybutylene terephthalate, preferably using a "melt blown" fiber process to attenuate the extruded fibers (i.e. to make the fibers thinner).
  • the polyethylene terephthalate or copolymer thereof of the porous element of the invention is a homopolymer of polyethylene terephthalate or a copolymer thereof having a melting point which is higher than the melting point of the thermoplastic core material in the bicomponent fiber.
  • polyesters used to make fibers are the product of reaction of ethylene glycol (1,2 ethanediol) and terephthalic acid (benzene-para-dicarboxylic acid). Each of these molecules has reactive sites at opposite ends. In this way, the larger molecule resulting from an initial reaction can react again in the same manner, resulting in long chains made of repeated units or "mers".
  • the same polymer is also industrially made with ethylene glycol and dimethyl terephthalate (dimethyl benzene-paradicarboxylate). It is believed that polyesters of a broad range of intrinsic viscosities are useful for this invention, although those with lower intrinsic viscosities are preferred.
  • Crystar 1946 or 3946 made by DuPont has been successfully used as the sheath-forming material in the production of the bicomponent fibers for this invention.
  • This copolymer has dimethyl isophthalate (dimethyl benzyl-meta-dicarboxylate)substituted for 17% of the dimethyl terephthalate, lowering the peak melting point from 258°C to 215°C. This melting point is still well above that of polypropylene (166°C).
  • DuPont's Crystar 3991 with 40% dimethyl isocyanate has a melting point of 160°C, i.e., slightly below the 166°C melting point of polypropylene.
  • copolymers of polyethylene terephthalate containing up to about 35 weight percent of dimethyl isocyanate or isocyanic acid will be commercially acceptable.
  • melt blown refers to the use of a high pressure gas stream at the exit of a fiber extrusion die to attenuate the fibers while they are in their molten state. Melt blowing of single polymer component fibers was initiated at the Naval Research Laboratory in 1951. The results of this investigation were published in Industrial Engineering Chemistry 48, 1342 (1956). Seven years later Exxon completed the first large semiworks melt blown unit demonstration. See, for example, Buntin U.S. Patent Nos. 3,595,245, 3,615,995 and 3,972,759 (the '245, '995 and '759 patents, the subject matters of which are incorporated herein in their entirety by reference) for a comprehensive discussion of the melt-blowing process.
  • Melt blown polypropylene monocomponent fibers are presently used in the production of a variety of products, including fine particle air and liquid filters, and high absorbing body fluid media (diapers).
  • such fibers have low stiffness and very low recovery when compressed.
  • they are not susceptible to thermal bonding and are difficult to bond by chemical means.
  • they are not commercially acceptable for the production of three-dimensional, self-supporting items such as ink reservoirs, cigarette filters, wicks for chemical and medical test devices, and flat or corrugated filter sheets.
  • the '165 patent provides a good definition of the type of melt blown polyesters which are recognized by the industry as problematic, but the solution proposed in the '165 patent appears environmentally questionable, or, at the very least, quite expensive when safely performed.
  • the present invention overcomes the lack of stability with the polyesters iterated in the '165 patent in a more commercially and ecologically acceptable manner.
  • sheath-core conjugates in this invention comprising a sheath of polyethylene terephthalate or a copolymer thereof over a thermoplastic core such as polypropylene or polybutylene terephthalate, are believed to be unique, whether melt blown or not, having attributes that would not have been expected.
  • the fiber be formed of a polymer having a lower melting point than the polymer conjugated therewith.
  • they may be heated to a temperature between the melting points of the polymers, enabling the lower melting point polymer at the surface to function as the bonding agent without deleteriously affecting the higher melting point polymer material.
  • the sheath must be formed of the lower melting point polymer or the conjugate will not have useful thermal bonding properties.
  • the sheath-core bicomponent fibers in the product of this invention have a continuous covering of a higher melting point polymer, namely polyethylene terephthalate or a copolymer thereof, over a lower melting point, preferably low shrinkage, polymer core such as polypropylene or polybutylene terephthalate.
  • a higher melting point polymer namely polyethylene terephthalate or a copolymer thereof
  • a lower melting point preferably low shrinkage, polymer core
  • Such fibers particularly when melt blown, are uniquely adapted for porous elements useful for diverse commercial applications. Yet, it is believed that early attempts to produce and then attenuate melt spun polyester/polypropylene bicomponent fibers were abandoned because of delamination at the fiber interface.
  • the method of this invention can include the production of fine fibers from such diverse polymers by melt blowing the sheath-core bicomponent structures.
  • a principal focus of this invention is elongated highly porous ink reservoir elements for marking and writing instruments.
  • Ink reservoirs have conventionally been formed of a fibrous bundle compacted together into a rod-shaped unit having longitudinal capillary passageways which extend therethrough between the fibers and which serve to hold the ink and release it at the required controlled rate.
  • the fibrous material generally employed for the production of ink reservoirs was plasticized cellulose acetate fibers, which could readily be heat-bonded into a unitary body, and which were compatible with all of the ink formulations then in use.
  • Bunzl et al. U.S. Patent No. 3,094,736 discloses a marking device having as the adsorbent body thereof a tow or tow segment gathered with its filaments randomly oriented primarily in a longitudinal direction and bonded at a plurality of spaced locations by a heat-activated plasticizer for such filaments.
  • An impermeable overwrap was used to give rigidity to the body and facilitate handling thereof.
  • filamentary tow is defined in the '736 patent, and such continuous filamentary tows are also discussed in Berger U.S. Patent Nos. 3,095,343 and 3,111,702 (the '343 and '702 patents, respectively, the subject matters of which are also incorporated herein in their entirety by reference).
  • Such filamentary tows usually comprise at least 50% cellulose acetate fibers.
  • Such tow bodies, bound with plasticizers, provide rigidity.
  • the '702 patent shows an apparatus for handling and steam-treating the tow material to form therefrom a continuous body of fibers randomly oriented primarily in a longitudinal direction.
  • the phrase, "randomly oriented primarily in a longitudinal direction" is intended to describe the condition of a body of fibers which are, as a whole, longitudinally aligned and which are, in the aggregate, in a parallel orientation, but which have short portions running more or less at random in non-parallel diverging and converging directions.
  • the '702 patent teaches bonding, tensioning and impregnating a raw tow into a plasticizer-impregnated layer of continuous uncrimped filaments, and then curing the continuous filamentary tow simultaneously with, or immediately after, gathering of such impregnated layer into a final raw shape. Apparatus is shown for handling such raw tow.
  • the raw tow is taken from a supply bale through a device having jets to separate the tow, and a plasticizing device adds plasticizer to the fibers.
  • the fibers are simultaneously gathered together and heated, thereby comprising a curing station.
  • thermoplastic fibers in particular, fine denier polyester fibers, such as polyethylene terephthalate, replaced cellulose acetate as the polymer of choice in the production of ink reservoir elements for disposable writing and marking instruments.
  • polyester fibers are practically impossible to thermally bond due to the highly crystalline nature of conventional polyethylene terephthalate fibers. Resin bonding is slow and expensive and greatly reduces ink absorption. Undrawn polyethylene terephthalate fibers are not crystallized and can be thermally bonded, but such amorphous polymers shrink excessively in normal use and become brittle.
  • polyester fiber ink reservoir elements were commercially produced in the form of an unbonded bundle of fibers compacted and held together in a rod-shaped unit by means of a film overwrap.
  • they could be provided with a small diameter plastic "breather” tube disposed between the fibrous bundle and the overwrap to serve as an air release passage, if necessary.
  • Such film-overwrapped polyester fiber ink reservoir elements when made with parallel continuous-filament fibers, have had adequate ink holding capacity and ink release properties for use with certain types of marking or writing instruments, primarily those employing fiber tips or nibs. Yet, with the more recent development of roller ball writing instruments which require a faster ink release, or "wetter" system, such ink reservoir elements are commercially unacceptable.
  • polyester sliver having random fibers has been used which holds the ink better at lower densities.
  • sliver-type polyester ink reservoir elements still tend toward undesirable softness and often suffer from unacceptable weight variation which makes it difficult to control ink flow to a roller marker.
  • the ink reservoir of the '005 patent provides a combination of ink holding capacity and ink release properties useful with various types of marking or writing instruments, including roller markers and plastic nibs.
  • Such ink reservoirs are formed from coherent sheets of flexible thermoplastic fibrous material composed of an interconnecting network of randomly arranged, highly dispersed, continuous-filament junctions which has been embossed with a multiplicity of longitudinally extending parallel grooves and formed or compacted into a dimensionally stable rod-shaped body whose longitudinal axis extends parallel to the embossed grooves.
  • This ink reservoir could be provided with a longitudinal slot extending continuously along the periphery of the entire length of its body if a "breather" passage was required for the particular barrel design.
  • a "breather" passage was required for the particular barrel design.
  • the ink reservoir of the 005 patent while overcoming many problems with prior art products, required the use of relatively expensive materials, having a complex shape, and, for this reason, has not found commercial acceptance.
  • polyester ink reservoirs are currently made by the process described in Berger U.S. Patent No. 4,729,808 (the '808 patent, the subject matter of which is incorporated herein in its entirety by reference) which utilizes a raw material stretch yarn, often referred to as "false twist stretch yarn", which has unusual properties including the ability to stretch and curl or twist.
  • false twist yarn requires the use of melt spun fibers, generally averaging over 2 denier per filament (dpf) - about 12 microns in diameter.
  • While larger fibers are useful in some wetter systems, they take up more volume, so that there is less interstitial space for holding ink and thus less capacity in the reservoir.
  • Small fiber size less than about 12 microns, which cannot be achieved with false twist yarn, provides better release pressure without reducing capacity. Higher release pressure, which minimizes leakers, a particular problem with some very low surface tension ink compositions, is difficult to realize with false twist yarn.
  • Increasing density to improve leakers further reduces capacity.
  • polyesters such as polyethylene terephthalate, which are uniquely effective in the production of ink reservoir elements because of their compatibility with ink formulations currently in use, are expensive compared to other polymer materials. Therefore, the ability to minimize the quantity of polyethylene terephthalate necessary to the production of an ink reservoir having acceptable ink holding capacity, while being capable of controllably releasing the ink in a marking or writing instrument, would be highly desirable.
  • the use of a bicomponent fiber which replaces a significant portion of the polyethylene terephthalate with a lower cost polymer is problematic because polyethylene terephthalate has a higher melting point than the common thermoplastic polymers with which it might be conjugated, such as polypropylene or polybutylene terephthalate.
  • the porous element according to the invention may thus be an ink reservoir element, said network of continuous fibers defining intercommunicating interstitial spaces capable of holding and controllably releasing a quantity of ink; such an element may be a porous rod further including [a] an elongated passageway extending the full length of said porous rod to define an air passage from one end to the other thereof and/or [b] a continuous film circumferentially enveloping said porous rod.
  • a marking or writing instrument may include such a reservoir element, the instrument comprising an elongated hollow barrel member closed at one end and carrying a marking or writing tip at the opposite end, the reservoir element contained within said barrel in contact with said tip, and a quantity of ink held by said reservoir element for controlled release through said tip.
  • Such an instrument may have an air passage defined by a longitudinal recess formed in a continuous film circumferentially enveloping said porous rod, said air passage extending continuously along the periphery of said porous rod from one end to the other.
  • the bicomponent fibers can be effectively used for many other commercially important products.
  • sheets of such fibers have excellent filtration properties making them particularly useful in high temperature filtration environments because of the relatively high melting point of polyethylene terephthalate.
  • the same porous rod which can be used as an ink reservoir element comprises a network of continuous fibers which defines tortuous interstitial paths effective for capturing fine particulate matter when a gas or liquid is passed therethrough as in a filtering application.
  • the porous element according to the invention may thus be a tobacco smoke filter element, said network of continuous fibers defining a tortuous interstitial path for passage of smoke therethrough, and the fibers thereof may carry additive (e.g. selected from activated charcoal and flavourant).
  • a filter portion comprising such a filler element may be connected to a tobacco portion of a filtered cigarette by tipping overwrap.
  • this invention has significant commercial applications in the production of wick reservoirs, that is, materials designed to take up a liquid and later controllably release the same as in an ink reservoir for a marking and writing instrument. It is also particularly useful in the production of filters, whether in sheet or rod form.
  • the porous element of the invention may thus be a lateral flow wick designed to transport ink between an ink reservoir and a rolling ball in a writing instrument; or a nib for extracting and applying ink from a reservoir to a surface used in a marking or writing instrument. Wicks of this nature are also useful in diverse medical applications, for example as a lateral flow wick to transport a bodily fluid to a test site in a diagnostic device.
  • Products made by the present invention are not only useful as wicks and wick reservoirs, they may also be used as absorption reservoirs, i.e., as a membrane to take up and simply hold a liquid as in a diaper or an incontinence pad; or as a capillary reservoir pad for absorbing excess ink in a printing device.
  • Absorption reservoirs of this type are also useful in medical applications e.g. as a reservoir for collecting and holding bodily fluids which have passed through a test site in a diagnostic test device; as an absorptive device for the removal of saliva or other bodily fluids from a bodily cavity; or as filtering material for filtering solid matter from bodily fluids in preparation for diagnostic testing or for therapeutic purposes.
  • a layer or pad of such material may be used in an enzyme immunoassay diagnostic test device where it will draw a bodily fluid through the fine pores of a thin membrane coated, for instance, with monoclonal antibodies that interact with antigens in the bodily fluid which is pulled through the membrane and then held in the absorption reservoir.
  • a porous element according to the invention wherein the surface of said bicomponent fibers is hydrophobic and wherein said element is [a] a filter material for use as a vent filter in a pipette tip or [b] a filtering material for use in an intravenous solution injection system.
  • the bicomponent fibers are highly attenuated as they exit the bicomponent sheath-core extrusion die using available melt blowing techniques to produce a web or roving wherein the fibers have, on the average, a diameter of about 12 microns or less, down to 5 and even 1 micron.
  • Melt spun fibers of a larger size or even larger melt blown fibers, on the order of, perhaps, 20 microns - are useful in certain applications, for example in some wicking applications where strength is more important than capillarity; yet, the finer melt blown fibers possible in this invention have significant advantages in most of the applications mentioned above.
  • these small diameter fibers provide high surface area, and an increased holding capacity as compared to currently available conventional ink reservoirs produced entirely of polyethylene terephthalate.
  • the fine fiber size of the melt blown bicomponent continuous filaments gives enhanced filtration efficiency, providing increased fiber surface area at the same weight of fiber.
  • the bicomponent fibers in this invention containing a polyethylene terephthalate continuous sheath on a polypropylene or other crystalline polymer core have unique and commercially important properties. Contrary to melt blown monocomponent polyester fibers, the melt blown bicomponent fibers in this invention are not brittle and evidence much less shrinkage under heat. The melt blown bicomponent fibers in this inventionmay shrink only about 6% in the amorphous stage and 0% after heating to or above 90°C to crystallize the polyethylene terephthalate. This compares with 40 to 60% shrinkage for conventional melt blown polyethylene terephthalate.
  • the stiffness of the fibers in this invention is greater than that of conventional melt blown polypropylene; this is reflected in higher and more resilient bulk. Moreover, the stiffness of the bicomponent fibers and bonding of the product permits the use of a less thick wrapping material than currently used in the production of ink reservoirs. Likewise, the solvent resistance of the melt blown bicomponent fibers herein, having a continuous crystallized polyethylene terephthalate covering, is also much superior to polypropylene fibers when exposed to aromatic, aliphatic and chlorinated solvents.
  • the fibrous webs or rovings formed in the method of the invention are thermally bondable with heated fluids such as hot air, saturated steam, or other heating media because of the unusual property of the polyethylene terephthalate sheath to undergo crystallization at a temperature less than the melting temperature of the core material.
  • heated fluids such as hot air, saturated steam, or other heating media
  • the polyethylene terephthalate sheath is still amorphous at up to 90°C or so in the collected melt blown web or roving.
  • the fibers are bonded at their points of contact and the polyethylene terephthalate is crystallized.
  • the higher melting temperature crystalline core material supports the sheath during the heating step and minimizes shrinkage of the bicomponent fiber as the polyethylene terephthalate is crystallized. Once heated to temperatures above about 90°C, however, the shaped product is relatively self-sustaining and the crystallized polyethylene terephthalate renders the sheath solvent resistant.
  • the method of this invention enables the fiber extrusion and melt blowing, and conversion of the resultant fiber web into an elongated substantially self-sustaining porous rod (which may be subdivided for use, for example, as ink reservoir elements or tobacco smoke filters), to be a one-step or continuous process.
  • the porous rod can be continuously overwrapped or covered with a film or coating, if desired, and an air passage can be continuously formed longitudinally along the periphery of the porous rod in an obvious manner.
  • the porous rod is to be used as a cigarette filter, it can be continuously encased in an air permeable or impermeable paper filter wrap, if desired, before the rod is cut into discrete filter rods or filter plugs.
  • the three-dimensional elements may be shaped, as by grinding or in any other conventional manner, depending upon their particular application.
  • elongated porous rod is used herein to describe many of these elements, it should be understood that this term is not intended to be limited to a cylindrical shape except where such a configuration would be appropriate.
  • the method of this invention preferably makes such substantially self-sustaining elongated elements by combining bicomponent extrusion technology with melt blown attenuation to produce a web or roving of highly entangled fine fibers with a sheath of substantially amorphous polyethylene terephthalate or a copolymer thereof which is bondable at a lower temperature than the melting point of the core material, and then gathering the web or roving and heating the same by a heated fluid, preferably saturated steam, or in a dielectric oven, to bond the fibers at their points of contact and crystallize the polyethylene terephthalate at the same time.
  • a heated fluid preferably saturated steam, or in a dielectric oven
  • Products incorporating porous elements of the invention can be useful commercially as 1) wick reservoirs, including ink reservoirs and marking and writing instruments incorporating the same; 2) filtering materials, including tobacco smoke filters and filtered cigarettes formed therefrom; 3) wicks for transporting liquid from one place to another by capillary action, including fibrous nibs for marking and writing instruments and capillary wicks in medical applications designed to transport a bodily fluid to a test site in a diagnostic device; and 4) absorption reservoirs, including membranes for taking up and holding a liquid as in a diaper or an incontinence pad, or in medical applications such as enzyme immunoassay diagnostic test devices wherein a pad of such material will draw a bodily fluid through a thin membrane and hold the fluid pulled therethrough.
  • a primary product of this invention is a high capacity ink reservoir for a marking or writing instrument defined by an elongated porous rod formed of a network of fine bicomponent fibers having a continuous sheath of polyethylene terephthalate or a copolymer thereof which is compatible with all currently available ink formulations and which provides an adequate release pressure to minimize "leakers” even when used in a roller ball pen or the like.
  • the method of manufacturing the specific polymers used in the production of the bicomponent fibers is not part of the invention. Processes for making these polymers are well known in the art and, as noted above, most commercially available polyethylene terephthalate materials or copolymers thereof can be used. While it is not necessary to utilize sheath and core materials having the same melt viscosity, as each polymer is prepared separately in the bicomponent melt blown fiber process, it may be desirable to select a core material, e.g.
  • polypropylene or polybutylene terephthalate of a melt index similar to the melt index of the sheath polymer, or, if necessary, to modify the viscosity of the sheath polymer to be similar to that of the core material to insure compatibility in the melt extrusion process through the bicomponent die.
  • Providing sheath-core components with compatible melt indices is not a significant problem to those skilled in this art with commercially available thermoplastic polymers and additives.
  • additives may be incorporated or compounded into the polymer prior to extrusion to provide the fibers and products produced therefrom with unique properties, e.g. increased hydrophilicity or even increased hydrophobicity.
  • polypropylene and polybutylene terephthalate are the preferred core materials for the reasons iterated below, other highly crystalline thermoplastic polymers such as high density polyethylene, as well as polyamides such as nylon 6 and nylon 66, can be used.
  • the main requirement of the core material is that it is crystallized when extruded or crystallizable during the melt blowing process.
  • Polyethylene terephthalate in contrast, normally requires a separate drawing stage for crystallization.
  • Polypropylene is a preferred core-forming material due to its low price and ease of processability. Polypropylene has also been found to be particularly useful in providing the core strength needed for production of fine fibers using melt blown techniques.
  • Various modified polypropylenes can be used as the core-forming material to achieve even better adhesion to the sheath such as DuPont's BYNEL CXA Series 5000 anhydride-modified polypropylenes, other acid anhydride (preferably maleic acid anhydride) polypropylenes, anhydride functionalized polypropylenes, adhesive polypropylenes such as Quantum Chemical Corporation's PLEXAR extrudable adhesive polypropylenes, or other reactive polypropylenes.
  • polybutylene terephthalate crystallizes easily and is not amorphous for any appreciable length of time. Thus, it is ineffective as a sheath-forming material according to this invention in that the resultant bicomponent fiber is not bondable.
  • a polyethylene terephthalate sheath/polybutylene terephthalate core bicomponent fiber has the advantage, however, of an especially effective bond between the sheath and core due to the similar properties in these related polyester polymers, and is stable to temperatures approaching 250°C, in contrast to the degradation of product at substantially lower temperatures using a polypropylene core bicomponent fiber.
  • the fiber 20 preferably has a polyethylene terephthalate or polyethylene terephthalate copolymer sheath 22 and a polypropylene or polybutylene terephthalate core 24.
  • the core material constitutes at least about 30%, and up to about 90% by weight of the overall fiber content.
  • the bicomponent melt blown process preferably utilized in the invention provides fine fibers with increased surface area having improved capillary pressure and absorbency over ordinary fibers, even those with non-round cross-sections.
  • the rate of flow of a liquid can be controlled through density changes only, when the smallest commercial fibers are used. With the melt blown techniques of this invention, the flow can be controlled by simply changing the size of the fiber.
  • melt blown bicomponent fibers with a non-round cross section having even further increased surface area can be produced which may be advantageous, for example, if the product is to be used as a filter.
  • the non-round fiber cross-section enhances the use of air when the fiber is attenuated by melt blowing techniques.
  • a trilobal or "Y" shaped fiber 20a is shown in Figure 2 with a sheath 22a and a core 24a.
  • a cross or "X" shaped bicomponent fiber as seen at 20b in Figure 3, having a sheath 22b and a core 24b, is illustrative of many multi-legged fiber core sections possible. It will be seen that, in each instance, the sheath of polyethylene terephthalate completely covers the core material. Failure to enclose any major portion of the core material minimizes or obviates many of the advantages of the invention.
  • FIGs 13 to 17 schematically illustrate preferred equipment used in making a bicomponent fiber, and processing the same into continuous, three-dimensional, porous elements - that can be subsequently subdivided to form, for example, ink reservoir elements to be incorporated into marking or writing instruments, or tobacco smoke filter elements to be incorporated into filtered cigarettes or the like.
  • the overall processing line is designated generally by the reference numeral 30 in Figure 13.
  • the bicomponent fibers are made in-line with the equipment utilized to process the fibers into the porous elements. Such an arrangement is practical with the melt blown techniques because of the small footprint of the equipment required for this procedure. While the in-line processing has obvious commercial advantages, it is to be understood that the invention is not so limited; bicomponent fibers and webs or rovings formed from such fibers may be separately made and processed according to the invention into diverse products in separate or sequential operations.
  • the fibers themselves can be made using standard fiber spinning techniques for forming sheath-core bicomponent filaments as seen, for example, in Powell U.S. Patent Nos. 3,176,345 or 3,192,562 or Hills U.S. Patent No. 4,406,850 (the '345, '562 and '850 patents, respectively, the subject matters of which are incorporated herein in their entirety by reference).
  • methods and apparatus for melt blowing of fibrous materials, whether they are bicomponent or not are well known. For example, reference is made to the aforementioned '245, '995 and '759 patents as well as Schwarz U.S. Patent Nos.
  • one form of a sheath-core melt blown die is schematically shown enlarged in Figures 14 and 15 at 35.
  • Molten sheath-forming polymer 36, and molten core-forming polymer 38 are fed into the die 35 and extruded therefrom through a pack of four split polymer distribution plates shown schematically at 40, 42, 44 and 46 in Figure 15 which may be of the type discussed in the aforementioned '850 patent.
  • the molten bicomponent sheath-core fibers 50 are extruded into a high velocity air stream shown schematically at 52, which attenuates the fibers 50, enabling the production of fine bicomponent fibers on the order of 12 microns or less.
  • a water spray shown schematically at 54 is directed transversely to the direction of extrusion and attenuation of the melt blown bicomponent fibers 50. The water spray cools the fibers 50 to enhance entanglement of the fibers while minimizing bonding of the fibers to each other at this point in the processing, thereby retaining the fluffy character of the fibrous mass and increasing productivity.
  • a reactive finish may be incorporated into the water spray to make the polyethylene terephthalate fiber surface more hydrophilic or "wettable".
  • a lubricant or surfactant can be added to the fibrous web in this manner, although unlike spun fibers which require a lubricant to minimize friction and static in subsequent drawing operations, melt blown fibers generally do not need such surface treatments.
  • the ability to avoid such additives is particularly important, for example, in medical diagnostic devices where these extraneous materials may interfere or react with the materials being tested.
  • the resultant product may be a porous element which readily passes a gas such as air
  • a gas such as air
  • a porous element according to the invention is used, for example, as a vent filter in a pipette tip or in an intravenous solution injection system.
  • the materials to so-treat the fiber are well known and the application of such materials to the fiber or porous element as they are formed is well within the skill of the art.
  • a stream of a particulate material such as granular activated charcoal or the like may be blown into the fibrous mass as it emanates from the die, producing excellent uniformity as a result of the turbulence caused by the high pressure air used in the melt blowing technique.
  • a liquid additive such as a flavorant or the like may be sprayed onto the fibrous mass in the same manner.
  • melt blown fibrous mass is continuously collected as a randomly dispersed entangled web or roving 60 on a conveyor belt shown schematically at 61 in Figure 13 (or a conventional screen covered vacuum collection drum as seen in the '759 patent, not shown herein) which separates the fibrous web from entrained air to facilitate further processing.
  • This web or roving 60 of melt blown bicomponent fibers is in a form suitable for immediate processing without subsequent attenuation or crimp-inducing processing.
  • the polyethylene terephthalate sheath material at this point in the processing is still amorphous.
  • the core material whether it be polypropylene, polybutylene terephthalate or other appropriate polymer, is crystalline, providing strength to the bicomponent fibers and precluding significant shrinkage of these materials.
  • the remainder of the processing line seen in Figure 13 may use apparatus known in the production of plasticized cellulose acetate tobacco smoke filter elements, although minor modifications may be required to individual elements thereof in order to facilitate heat bonding of the fibers.
  • Exemplary apparatus will be seen, for example, in Berger U.S. Patent Nos. 4,869,275, 4,355,995, 3,637,447 and 3,095,343 (the '275, '995,'447 and '343 patents, the subject matters of which are incorporated herein in their entirety by reference).
  • the web or roving of melt blown sheath-core bicomponent fibers 60 is not bonded or very lightly bonded at this point and is pulled by nip rolls 62 into a stuffer jet 64 where it is bloomed as seen at 66 and gathered into a rod shape 68 in a heating means 70 which may comprise a heated air or steam die as shown at 70a in Figure 16 (of the type disclosed in the '343 patent), or a dielectric oven as shown at 70b in Figure 17.
  • the heating means raises the temperature of the gathered web or roving above about 90°C to cure the rod, first softening the sheath material to bond the fibers to each other at their points of contact, and then crystallizing the polyethylene terephthalate sheath material.
  • the element 68 is then cooled by air or the like in the die 72 to produce a stable and relatively self-sustaining, highly porous fiber rod 75.
  • the bonding of the fibers need only provide sufficient strength to form the rod and maintain the pore structure.
  • the porous rod 75 can be coated with a plastics material in a conventional manner (not shown) or wrapped with a plastics film or a paper overwrap 76 as schematically shown at 78 to produce a wrapped porous rod 80.
  • the continuously produced porous fiber rod 80, whether wrapped or not, may be passed through a standard cutter head 82 at which point it is cut into preselected lengths and deposited into an automatic packaging machine.
  • Each element 90 comprises an elongated air-permeable body of fine melt blown bicomponent fibers such as shown at 20 in Figure 1, bonded at their contact points to define a high surface area, highly porous, self-sustaining element having excellent capillary properties when used as a reservoir or wick and providing a tortuous interstitial path for passage of a gas or liquid when used as a filter.
  • elements 90 produced in accordance with this invention need not be of uniform construction throughout as illustrated in Figure 4.
  • a continuous longitudinally extending peripheral groove such as seen at 92 in Figures 6 and 7 can be provided as an air passage in an ink reservoir 95 (which may or may not include a coating or film wrap 96) if necessary for use in, for example, a writing instrument as shown generally at 100 in Figure 5.
  • the writing instrument 100 may include a roller ball wick 102 which can also be produced by this invention and which engages a roller ball writing tip 103 in a conventional manner.
  • the ink reservoir 95 is contained within a barrel 104 in fluid communication with the roller ball wick 102 to controllably release a quantity of ink 106 to the roller ball 103 in the usual way.
  • the roller ball wick 102 will generally have a higher capillarity than the reservoir 95, with the fibers thereof being more longitudinally oriented so as to draw the ink 106 from the reservoir 95 and feed the same to the roller ball 103. It is well within the skill of the art to form the three-dimensional porous elements of the invention with higher or lower capillarity depending upon the particular application by controlling, for example, the speed with which the fibrous mass is fed into the forming devices, the size and shape of the forming devices and other such obvious processing parameters.
  • a marking device is shown generally at 120 as including a conventional barrel 122 containing an ink reservoir 95a in fluid communication with a fibrous wick or nib 124 which may be of the type commonly referred to as a "felt tip".
  • the fibrous wick or nib 124 may be provided with the shape shown in Figure 8, or any other desired shape, by conventional grinding techniques well known to those skilled in this art.
  • the nib 124 is generally denser, with the fibers generally more longitudinally oriented, than the fibers from which the reservoir 95a are made, in order to provide the nib with the higher capillarity necessary to draw the ink from the reservoir in use.
  • Elements 90 can also be provided with interior pockets, exterior grooves, crimped portions or other modifications (not shown) as in the aforementioned prior patents to Berger, or others, particularly if they are to be used as tobacco smoke filters.
  • a conventional filtered cigarette is illustrated at 110 in Figure 10 as comprising a tobacco rod 112 covered by a conventional cigarette paper 114 and secured to a filter means comprising a discrete filter element 115, such as would result from further subdividing a filter rod 116 shown in Figure 9.
  • the filter element 115 may be overwrapped with an air permeable or air impermeable plugwrap 118 and secured to the tobacco rod 112 in a conventional manner as by standard tipping wrap 119.
  • a diagnostic test device is shown generally by reference numeral 130 as comprising a shell or housing 132 encasing a test site 134 which may be, for example, a porous membrane or the like, with an exposed wick element 136 which may be made according to this invention, an internal wick 138 of a higher capillarity, also made by the invention, and an absorptive reservoir 140, also a product of this invention.
  • a device of this type is capable, for example, of collecting a bodily fluid with the exposed wick 136, carrying the same via the internal wick 138 to and through the test site 134, and then absorbing and holding the liquid in the reservoir 140.
  • this device utilizes porous elements according to this invention as a lateral flow wick designed to transport a liquid to a test site, and then also provides a reservoir to draw the liquid past the test site and then to hold the liquid.
  • Figure 12 is a schematic showing of the use of a plug 152 of filtering material according to this invention as a vent filter in a pipette designated generally by the reference numeral 150 (or as an in-line filter in, for example, an intravenous solution injection system).
  • the pad or plug of material 152 formed according to this invention may have been pre-treated to render the fibers or the element in general hydrophobic so that air may pass, but liquids will not.
  • In-line filters are well known and are commonly used in vitro to remove undesirable materials from a sample prior to a diagnostic test, or in vivo , for example, in flushing the kidneys prior to kidney dialysis, or to filter out blood clots in open heart surgery.
  • Pads of material made according to this invention can also be used as capillaries to absorb excess ink in a printing device, for example, as an "overshot pad” in an ink jet printer. Likewise, such materials can be used as an absorptive device for the removal of saliva and other bodily fluids from the oral cavity.
  • the resulting melt blown webs were shaped into cylindrical rods by pulling them through dies where the fibers were exposed to live steam.
  • the steam heating not only shaped and bonded the web, but also crystallized the fibers.
  • the crystallized fibers were dimensionally stable to subsequent heating and did not swell when submerged in ink carrier solvents, such as low alcohols, ketones and xylene and formic acid-containing inks. compares various properties of cylindrical ink reservoirs formed from the melt blown bicomponent fibers with the more conventional monocomponent polyethylene terephthalate fiber reservoirs of the prior art.
  • PET Polyethylene Terephthalate
  • PP Polypropylene
  • the polyethylene terephthalate/polypropylene fiber product shows a substantially equal liquid absorption using about 40% less fiber weight.
  • Raw material costs are reduced not only because of lower overall polymer weights, but also because of the lower cost of polypropylene as compared with polyethylene terephthalate, particularly on a volume basis (the specific gravity of polyethylene terephthalate is 1.38 g/cm 3 , while that of polypropylene is only 0.90 g/cm 3 ).
  • the market price of polyethylene terephthalate per cubic inch, listed in the November 1995 issue of Plastics Technology is 3.6 cents for railcar quantities while the comparable price for polypropylene is only 1.3 cents.
  • the melt blown bicomponent fibers in Samples 1-3 contain approximately 40% polyethylene terephthalate by weight. Again, the higher absorption of the bicomponent fiber elements of this invention is seen when compared to the same quantity of conventional polyethylene terephthalate crimp yarn product. Table 2 also illustrates the advantage of increasingly small fibers, which can only be provided with the melt blowing process preferred in this invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Multicomponent Fibers (AREA)
  • Nonwoven Fabrics (AREA)

Claims (24)

  1. Im Wesentlichen selbsttragendes dreidimensionales poröses Element, das aus einer/m Bahn oder Roving aus flexiblem thermoplastischem Fasermaterial gebildet ist, umfassend ein Verbindungsnetz aus hochdispergierten kontinuierlichen Fasern, die zufallsmäßig hauptsächlich in einer Längsrichtung orientiert und an Kontaktstellen aneinander gebunden sind, wobei wenigstens ein großer Teil der genannten kontinuierlichen Fasern Bikomponentenfasern sind, umfassend einen Kern aus thermoplastischem Polymermaterial, das im Wesentlichen vollständig von einer Hülse aus Polymermaterial umgeben ist, ausgewählt aus Polyethylenterephthalat und Copolymeren davon, wobei das genannte Hülsenmaterial einen höheren Schmelzpunkt hat als das genannte Kernmaterial.
  2. Element nach Anspruch 1, wobei die genannten Bikomponentenfasern im Durchschnitt einen Durchmesser von etwa 12 Mikron oder weniger haben.
  3. Element nach Anspruch 2, wobei die genannten Bikomponentenfasern durch kontinuierliches Schmelzblasextrudieren der genannten Hülse-Kern-Materialien hergestellt werden.
  4. Element nach Anspruch 1 oder 2 oder 3, wobei das genannte Kernmaterial Polypropylen oder Polybutylenterephthalat ist.
  5. Element nach einem der Ansprüche 1 bis 4, wobei das genannte Kernmaterial zwischen 30 und 90 Gew.-% der gesamten Bikomponentenfaser ausmacht.
  6. Element nach einem der Ansprüche 1 bis 5, wobei die genannten Bikomponentenfasern einen "Y"-förmigen oder "X"-förmigen oder einen anderen nichtrunden Querschnitt haben.
  7. Element nach einem der Ansprüche 1 bis 6, das ein Farbvorratselement ist, wobei das genannte Netzwerk aus kontinuierlichen Fasern miteinander in Verbindung stehende Zwischengitterräume definiert, die eine Farbmenge halten und kontrolliert abgeben können.
  8. Element nach Anspruch 1, das ein Tabakrauchfilterelement ist, wobei das genannte Netzwerk von kontinuierlichen Fasern einen gewundenen Zwischengitterpfad für den Durchfluss von Rauch definieren.
  9. Element nach Anspruch 1, das [a] ein Docht zum Transportieren von Flüssigkeit von einem Ort zu einem anderen durch Kapillarwirkung ist, z.B. ein Seitenflussdocht, der so ausgelegt ist, dass er Farbe zwischen einem Farbvorrat und einer Rollkugel in einem Schreibinstrument transportiert; oder [b] eine Spitze zum Extrahieren und Aufbringen von Farbe von einem Vorrat auf eine Oberfläche ist, die in einem Markier- oder Schreibinstrument verwendet wird; oder [c] ein Seitenflussdocht ist, der so ausgelegt ist, dass er Körperfluid zu einem Testort in einer Diagnostikvorrichtung transportiert; oder [d] ein absorptionsfähiger Vorrat zum Aufnehmen und Halten von Flüssigkeiten ist; oder [e] ein Vorrat zum Sammeln und Halten von Körperfluiden ist, die durch einen Testort in einer diagnostischen Testvorrichtung geflossen sind; oder [f] ein Kapillarvorratskissen zum Absorbieren von überschüssiger Farbe in einem Druckgerät ist; oder [g] eine absorptionsfähige Vorrichtung zum Entfernen von Speichel oder anderen Körperfluiden aus einem Körperhohlraum ist; oder [h] ein Filtermaterial zum Ausfiltern von fester Materie aus Körperfluiden in Vorbereitung für einen Diagnostiktest oder für therapeutische Zwecke ist.
  10. Element nach Anspruch 1, wobei die Oberfläche der genannten Bikomponentenfasern hydrophob ist und wobei das genannte Element [a] ein Filtermaterial für die Verwendung als Lüftungsfilter in einer Pipettenspitze oder [b] ein Filtermaterial für die Verwendung in einem intravenösen Lösungsinjektionssystem ist.
  11. Farbvorratssystem nach Anspruch 7, das ein poröser Stab ist, ferner mit [a] einem länglichen Verbindungsweg, der über die volle Länge des genannten porösen Stabes verläuft, um einen Luftkanal von einem Ende zum anderen davon zu definieren, und/oder [b] einer kontinuierlichen Folie, die den genannten porösen Stab umfangsmäßig umhüllt.
  12. Markier- oder Schreibinstrument, umfassend ein längliches hohles Zylinderelement, das an einem Ende geschlossen ist und eine Markierungs- oder Schreibspitze am gegenüberliegenden Ende trägt, ein Farbvorratselement nach Anspruch 7, das in dem genannten Zylinder in Kontakt mit der genannten Spitze enthalten ist, und eine Farbmenge, die von dem genannten Vorratselement für eine kontrollierte Abgabe durch die genannte Spitze gehalten wird.
  13. Instrument nach Anspruch 12 mit einem Vorratselement nach Anspruch 11 und einem Luftkanal, der durch eine longitudinale Aussparung definiert wird, die in einer kontinuierlichen Folie ausgebildet ist, die den genannten porösen Stab umfangsmäßig umhüllt, wobei der genannte Luftkanal kontinuierlich entlang der Peripherie des genannten porösen Stabes von einem Ende zum anderen verläuft.
  14. Filterelement nach Anspruch 8, das ferner ein Zusatzmittel beinhaltet, das von den Fasern des genannten Filterelementes getragen wird, wobei das genannte Zusatzmittel vorzugsweise aus Aktivkohle und einem Geschmacksmittel ausgewählt ist.
  15. Filterstab, umfassend eine Vielzahl von Filterelementen nach Anspruch 8 oder 14, die in einer Endean-Ende-Beziehung zu einem Stück miteinander verbunden sind.
  16. Zigarette, umfassend einen Tabakabschnitt und einen Filterabschnitt, die durch Manschetteneinwicklung miteinander verbunden sind, wobei der genannte Filterabschnitt ein Filterelement nach Anspruch 8 oder 14 umfasst.
  17. Verfahren zur Herstellung eines im Wesentlichen selbsttragenden länglichen porösen Elementes, umfassend die folgenden Schritte:
    a) Bereitstellen separater Quellen eines schmelzflüssigen, hülsenbildenden Materials, ausgewählt aus Polyethylenterephthalat und Copolymeren davon, und eines schmelzflüssigen kernbildenden thermoplastischen Materials;
    b) kontinuierliches Extrudieren der genannten schmelzflüssigen kernbildenden und hülsenbildenden Materialien durch eine Vielzahl von Öffnungen in einer zusammenpassenden Hülse-Kern-Düse, um eine Vielzahl von Bikomponentenfasern bereitzustellen, wobei jede Faser einen kontinuierlichen Kern des genannten kernbildenden Materials umfasst, das im Wesentlichen vollständig von einer Hülse aus dem genannten hülsenbildenden Material umgeben wird;
    c) Sammeln der genannten Bikomponentenfasern auf einer sich ständig bewegenden Oberfläche zum Bilden einer/s stark verschlungenen Bahn oder Roving aus den genannten Bikomponentenfasern in der Form eines Verbindungsnetzes von hochdispergierten kontinuierlichen Fasern, die zufallsmäßig hauptsächlich in der Bewegungsrichtung der genannten sich bewegenden Oberfläche orientiert sind;
    d) Aufnehmen der/des genannten Bahn oder Roving aus Bikomponentenfasern;
    e) Erhitzen der/des genannten Bahn oder Roving zum Binden der genannten Fasern aneinander an ihren Kontaktpunkten und zum Kristallisieren des genannten hülsenbildenden Materials;
    f) Kühlen des/der genannten erhitzten aufgenommenen Bahn oder Roving zum Bilden eines gebundenen dreidimensionalen kontinuierlichen porösen Elementes, das miteinander verbundene Zwischengitterräume hat und in dem das genannte hülsenbildende Material einen höheren Schmelzpunkt hat als das genannte kernbildende Material; und
    g) Schneiden des genannten gebundenen kontinuierlichen porösen Elementes in diskrete Längen.
  18. Verfahren nach Anspruch 17, wobei die genannte Vielzahl von Bikomponentenfasern mit einem unter Druck stehenden Gas in Kontakt gebracht wird, während die Bikomponentenfasern die Hülse-Kern-Düse verlassen, um die genannten Bikomponentenfasern dünner zu machen, während sie noch in ihrem schmelzflüssigen Zustand sind.
  19. Verfahren nach Anspruch 18, wobei die Dicke der genannten Fasern reduziert wird, um ein(e) Bahn oder Roving aus Fasern mit einem durchschnittlichen Faserdurchmesser von etwa 12 Mikron oder weniger zu erzeugen.
  20. Verfahren nach einem der Ansprüche 17 bis 19, wobei die Bikomponentenfasern auf kontinuierliche In-line-Weise zu dem genannten porösen Element gebildet und verarbeitet werden.
  21. Verfahren nach einem der Ansprüche 17 bis 20, wobei das genannte kernbildende Material Polypropylen oder Polybutylenterephthalat ist.
  22. Verfahren nach einem der Ansprüche 17 bis 21, wobei die genannten Öffnungen der genannten Hülse-Kern-Düse, durch die die genannten Bikomponentenfasern extrudiert werden, nicht kreisförmig sind, so dass Bikomponentenfasern mit einem nichtrunden Querschnitt (z.B. einem "Y"-förmigen oder "X"-förmigen Querschnitt) entstehen.
  23. Verfahren nach einem der Ansprüche 17 bis 22, ferner umfassend das Integrieren eines Zusatzmittels (z.B. Aktivkohle oder ein Geschmacksmittel) in die genannte Vielzahl von Bikomponentenfasern, während die genannten Bikomponentenfasern die Hülse-Kern-Düse verlassen.
  24. Verfahren nach einem der Ansprüche 17 bis 23, ferner umfassend einen oder mehrere der folgenden Schritte: [i] kontinuierliches Ausbilden einer longitudinalen Aussparung in dem genannten porösen Element entlang dessen Peripherie; [ii] kontinierliches Bedecken des genannten porösen Elementes mit einer Außenhülse vor dem Schneiden desselben in diskrete Längen; [iii] kontinuierliches Einwickeln des genannten porösen Elementes in ein Streifenmaterial zum Bilden einer Außenhülse; und [iv] Formen des genannten porösen Elementes zu einem Stab und Einwickeln des genannten porösen Stabes in ein Filterspitzenmaterial vor dem Schneiden desselben in diskrete Längen.
EP02076724A 1995-06-06 1996-06-04 Poröses Element Expired - Lifetime EP1230863B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/470,594 US5607766A (en) 1993-03-30 1995-06-06 Polyethylene terephthalate sheath/thermoplastic polymer core bicomponent fibers, method of making same and products formed therefrom
US470594 1995-06-06
EP96919167A EP0881889B1 (de) 1995-06-06 1996-06-04 Polyethylen Terephthalate Schutzhülle/Thermoplastischer Polymerkern aus Zweikomponentenfasern und Produkte

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
EP96919167A Division EP0881889B1 (de) 1995-06-06 1996-06-04 Polyethylen Terephthalate Schutzhülle/Thermoplastischer Polymerkern aus Zweikomponentenfasern und Produkte

Publications (3)

Publication Number Publication Date
EP1230863A2 EP1230863A2 (de) 2002-08-14
EP1230863A3 EP1230863A3 (de) 2003-03-19
EP1230863B1 true EP1230863B1 (de) 2004-12-15

Family

ID=26144751

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02076724A Expired - Lifetime EP1230863B1 (de) 1995-06-06 1996-06-04 Poröses Element

Country Status (2)

Country Link
EP (1) EP1230863B1 (de)
DK (1) DK1230863T3 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022170234A1 (en) * 2021-02-08 2022-08-11 Porex Technologies Corporation Seamless filtration media and methods of use

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11633307B2 (en) * 2019-01-29 2023-04-25 L'oreal Porous formulation storage cushion, formulation delivery system, and method of manufacturing a porous formulation storage cushion

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5940938B2 (ja) * 1978-11-15 1984-10-03 チッソ株式会社 棒状繊維成形体の製造方法
US4713291A (en) * 1984-09-06 1987-12-15 Mitsubishi Rayon Company Ltd. Fragrant fiber
JPS6183315A (ja) * 1985-05-07 1986-04-26 Kureha Chem Ind Co Ltd 同心複合糸
DE68917784T2 (de) * 1988-05-27 1995-01-05 Kuraray Co Leitfähiges zusammengesetztes Filament und Verfahren zur Herstellung desselben.

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022170234A1 (en) * 2021-02-08 2022-08-11 Porex Technologies Corporation Seamless filtration media and methods of use

Also Published As

Publication number Publication date
EP1230863A3 (de) 2003-03-19
DK1230863T3 (da) 2005-04-25
EP1230863A2 (de) 2002-08-14

Similar Documents

Publication Publication Date Title
US5607766A (en) Polyethylene terephthalate sheath/thermoplastic polymer core bicomponent fibers, method of making same and products formed therefrom
KR100359754B1 (ko) 복합성분섬유및이섬유로형성된담배연기필터
US20150125504A1 (en) Bicomponent fibers, products formed therefrom and methods of making the same
US7888275B2 (en) Porous composite materials comprising a plurality of bonded fiber component structures
US6026819A (en) Tobacco smoke filter incorporating sheath-core bicomponent fibers and tobacco smoke product made therefrom
EP0984706A1 (de) Tabakrauchfilter aus polyvinylalkohol, produkte, die diese filter verwenden,verfahren sowie apparat zur herstellung derselben
US20030194260A1 (en) Method and apparatus for making NIBS and ink reservoirs for writing and marking instruments and the resultant products
US3079930A (en) Process and apparatus for manufacturing filters
EP1489929B1 (de) Verfahren und einrichtung zum auftragen von additiv auf einen vliesstoff sowie vliesstoff
US4357379A (en) Melt blown product
US4267002A (en) Melt blowing process
EP1230863B1 (de) Poröses Element
GB2170391A (en) Adhesive application method for manufacturing cigarette filter elements
US4726862A (en) Process for producing tubular shaped fibrous articles
US7022200B2 (en) Method of making adhesive-free bonded porous thermoplastic nibs for markers and highlighter applications
CA1257520A (en) Thermally bonded polyolefin gas filters

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20020527

AC Divisional application: reference to earlier application

Ref document number: 881889

Country of ref document: EP

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

RIC1 Information provided on ipc code assigned before grant

Ipc: 7D 01F 8/14 B

Ipc: 7A 24D 3/14 A

Ipc: 7A 24D 3/08 B

Ipc: 7D 01F 8/06 B

Ipc: 7B 43K 15/02 B

Ipc: 7D 04H 1/00 B

Ipc: 7B 43K 8/03 B

Ipc: 7D 01D 5/34 B

17Q First examination report despatched

Effective date: 20031016

AKX Designation fees paid

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AC Divisional application: reference to earlier application

Ref document number: 0881889

Country of ref document: EP

Kind code of ref document: P

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 69634057

Country of ref document: DE

Date of ref document: 20050120

Kind code of ref document: P

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

REG Reference to a national code

Ref country code: CH

Ref legal event code: NV

Representative=s name: PATENTANWAELTE SCHAAD, BALASS, MENZL & PARTNER AG

REG Reference to a national code

Ref country code: GR

Ref legal event code: EP

Ref document number: 20050401047

Country of ref document: GR

REG Reference to a national code

Ref country code: DK

Ref legal event code: T3

REG Reference to a national code

Ref country code: PT

Ref legal event code: SC4A

Free format text: AVAILABILITY OF NATIONAL TRANSLATION

Effective date: 20050310

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 20050516

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 20050519

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: PT

Payment date: 20050523

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: MC

Payment date: 20050601

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20050617

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20050621

Year of fee payment: 10

Ref country code: IE

Payment date: 20050621

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FI

Payment date: 20050622

Year of fee payment: 10

Ref country code: CH

Payment date: 20050622

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DK

Payment date: 20050623

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GR

Payment date: 20050628

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: LU

Payment date: 20050629

Year of fee payment: 10

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2234977

Country of ref document: ES

Kind code of ref document: T3

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20050708

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 20050725

Year of fee payment: 10

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20050916

ET Fr: translation filed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060604

Ref country code: AT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060604

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060605

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060605

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060605

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060630

Ref country code: MC

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060630

Ref country code: DK

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060630

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060630

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20061204

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070101

REG Reference to a national code

Ref country code: DK

Ref legal event code: EBP

REG Reference to a national code

Ref country code: PT

Ref legal event code: MM4A

Free format text: LAPSE DUE TO NON-PAYMENT OF FEES

Effective date: 20061204

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

EUG Se: european patent has lapsed
NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20070101

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20070228

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20060605

BERE Be: lapsed

Owner name: *FILTRONA RICHMOND INC.

Effective date: 20060630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060604

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070104

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

Free format text: REGISTERED BETWEEN 20110113 AND 20110119

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 69634057

Country of ref document: DE

Representative=s name: KUHNEN & WACKER PATENT- UND RECHTSANWALTSBUERO, DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 69634057

Country of ref document: DE

Owner name: FILTRONA POROUS TECHNOLOGIES CORP., US

Free format text: FORMER OWNER: FILTRONA RICHMOND, INC., COLONIAL HEIGHTS, US

Effective date: 20121009

Ref country code: DE

Ref legal event code: R082

Ref document number: 69634057

Country of ref document: DE

Representative=s name: KUHNEN & WACKER PATENT- UND RECHTSANWALTSBUERO, DE

Effective date: 20121009

Ref country code: DE

Ref legal event code: R081

Ref document number: 69634057

Country of ref document: DE

Owner name: FILTRONA POROUS TECHNOLOGIES CORP., COLONIAL H, US

Free format text: FORMER OWNER: FILTRONA RICHMOND, INC., COLONIAL HEIGHTS, VA., US

Effective date: 20121009

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20150527

Year of fee payment: 20

Ref country code: GB

Payment date: 20150603

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20150625

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 69634057

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20160603

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20160603