EP2072670A1 - Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande - Google Patents

Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande Download PDF

Info

Publication number
EP2072670A1
EP2072670A1 EP08161414A EP08161414A EP2072670A1 EP 2072670 A1 EP2072670 A1 EP 2072670A1 EP 08161414 A EP08161414 A EP 08161414A EP 08161414 A EP08161414 A EP 08161414A EP 2072670 A1 EP2072670 A1 EP 2072670A1
Authority
EP
European Patent Office
Prior art keywords
polymer material
layer
fibers
fiber
polymer
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.)
Withdrawn
Application number
EP08161414A
Other languages
German (de)
English (en)
Inventor
Robert Crook
Robert Eberhardt
Arved Westerkamp
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.)
Voith Patent GmbH
Original Assignee
Voith Patent GmbH
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
Application filed by Voith Patent GmbH filed Critical Voith Patent GmbH
Publication of EP2072670A1 publication Critical patent/EP2072670A1/fr
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F7/00—Other details of machines for making continuous webs of paper
    • D21F7/08—Felts
    • D21F7/083—Multi-layer felts
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F1/00—Wet end of machines for making continuous webs of paper
    • D21F1/0027—Screen-cloths
    • D21F1/0036—Multi-layer screen-cloths

Definitions

  • the present invention relates to a belt for a machine for producing sheet material, in particular paper or cardboard, and to a method for producing such a belt.
  • the endless belts used, for example, in press sections of paper machines move together with the web material to be produced through one or more press nips, where, on the one hand, the web material is compacted, on the other hand, liquid is pressed out of it by the pressing together of two rollers with the interposition of the belt and the web material to be produced becomes.
  • the pressed-out liquid should be removed with or through the band.
  • this band it is necessary to provide this band with a porous or voided structure suitable for receiving the liquid.
  • such a structure is of course also subject to the pressing load occurring in the area of a press nip, so that the risk of material fatigue due to the constant compression and relaxation or the porosity and thus the available cavities can greatly decrease over the service life.
  • this object is achieved by a belt, in particular press felt, for a machine for producing web material, in particular paper or cardboard, comprising a support structure and at least one layer of fiber material, wherein at least a part of the fibers of the at least one Layer of fibrous material is at least partially coated with a film-forming first polymer material and wherein a second polymer material and fibers of the at least one fiber layer, a fluid-permeable composite structure is formed by the second polymer material formed between these fibers only partially filled and / or bridged ,
  • At least one layer of fiber material at least a portion of the fibers is at least partially coated with a film of a first polymeric material.
  • a permeable composite structure of a second polymer material and fibers of the fiber layer is formed by the second polymer material partially filling and / or bridging voids formed between fibers of the at least one fiber layer.
  • a structure constructed from the second polymer material is provided, which in its spatial configuration is in particular at least partially connected, preferably completely coherent and irregular. Fibers of the fiber layer are at least partially embedded in the polymeric structure.
  • the effects generated by two polymer materials interact.
  • the fibers or at least a part of them are coated with a first film-forming polymer material and thereby supported in their structure or stiffened.
  • this coating can form a crosslinking of the individual fibers with one another, so that, taking into account the elastic properties of the polymer material intended for the coating, a significantly better return characteristic can be combined with reduced material fatigue.
  • a second polymer material forming a permeable composite structure, which bridges and / or fills in particular cavities between the already fibers of the at least one fiber layer, the water absorption and removal capacity of this layer can be adjusted in a targeted manner.
  • the second polymer material per se is non-porous or permeable, in particular, for example, not foamed, but that a permeable composite structure is formed by only partially bridging and / or filling the cavities formed between the fibers.
  • At least some of the fibers of the at least one fiber layer are glued together at fiber crossing and / or fiber contact points by the first polymer material forming the film.
  • the bonding of the fibers of the layer forms a coherent network of interconnected fibers. This fiber network contributes significantly to the elastic properties and the resilience of the at least one layer of fibrous material.
  • the permeable composite structure comprising the second polymer material preferably comprises at least partially coherent spatial and / or areal polymeric structures which are arranged irregularly in the at least one layer of fiber material.
  • the second polymer material forms a one-piece, ie, completely coherent, and permeable polymer layer in the at least one layer of fibrous material.
  • the polymer layer is in this case in particular elastically compressible.
  • the polymer layer can extend over the width of the layer of fiber material or only over part of the width of the layer of fiber material. In both cases, however, the polymer layer extends over the entire length of the strip.
  • a one-piece polymer layer is to be understood here as meaning a polymer layer which is formed from a single coherent piece.
  • the polymer layer has openings extending therethrough, the openings in the polymer layer being formed by the polymer material forming the polymer layer only partially filling and / or bridging voids formed between fibers of the fiber layer.
  • the fiber material if it is, for example, of polyamide, for example, be dissolved out by means of formic acid.
  • a particularly preferred embodiment of the invention provides that the second polymer material at least partially filling and / or bridging the interstices between fibers is at least partially, in particular completely, attached to portions of the fibers which are coated with the first polymer material forming the film.
  • the first polymer material forming the film additionally acts as a semi-intermediate between the second polymer material and the fibers of the at least one fiber layer.
  • the first polymeric material and the second polymeric material preferably each comprise an elastomeric polymer, in particular, the first and second polymeric materials are an elastomeric polymer.
  • the second polymer material comprises, alone or in combination, a thermoplastic elastomer, in particular a thermoplastic elastomeric polyurethane, a polyether blockpolyamide, a polyamide preferably of the types PA 11, PA 12, PA 6.10 or PA 6.12, in particular the second polymer material is one of the abovementioned materials.
  • the first polymer material can, for example, in the form of an aqueous dispersion of particulate first Polymer material are applied in the at least one layer of fiber material.
  • aqueous dispersions are known, for example, under the name "witcobond polymer dispersion" and are obtained, for example, from Baxenden Chemicals Ltd. distributed in England.
  • the first polymeric material to which the fibers are coated has a higher melting point than the second polymeric material.
  • the second polymer material forming a permeable composite structure after the fibers have already been coated with the first polymer material without affecting the coating of the fibers required to melt the starting material for the second polymer material forming a permeable composite structure.
  • the fiber of the first polymer material, at least partially covering the fibers, preferably has a thickness in the range from 1 ⁇ m to 20 ⁇ m.
  • the film formed from the first polymer material has a uniform thickness.
  • At least a portion of the fibers of the at least one layer of fibrous material may be coated with multiple film layers of first polymeric materials. It is conceivable in this connection that at least some of the several film layers have mutually different properties. These different properties may, for example, result from mutually different first polymer materials which are used for the respective film layers.
  • an outer fiber layer in which the first and the second polymer material is introduced, provides a web material contact side of the tape.
  • the first and second polymeric materials have mutually different elastic properties.
  • the fibers of the first polymer material covering at least one fiber layer can be up to a depth of 10% to 100%, preferably to a depth of 30% to 100%, most preferably to a depth of 50%. extend to 100%, based on the total thickness of the tape.
  • good interfacial bonding of the second polymeric material may be provided regardless of whether the second polymeric material is capable of the entire thickness of the layer or only locally in a limited thickness range is arranged from fiber material.
  • a further concrete embodiment of the invention provides that, starting from the web material contact side, the voids between fibers of the at least one fiber layer bridging and / or filling second polymer material to a depth of 10% to 50%, preferably up to a depth of 10% 30%, based on the total thickness of the strip.
  • the second polymer material which partially fills the cavities between fibers of the at least one fiber layer does not extend over the entire thickness of the fiber layer, but is arranged substantially in the region of the web material contact side.
  • the second polymer material filling the cavities in the region of the web material contact side provides large local area elements, whereby significantly lower local pressure differences are produced on the web material contact side as the band passes through a press nip than with an uncoated fiber web providing the web material contact side. This has a particularly positive effect on a uniform and mark-free drainage of the paper web in the press nip.
  • the procedure is such that the second polymer material at least partially, in particular completely, attaches to sections of the fibers already coated with the first polymer material.
  • the first polymer film material forming a film for example, after the second polymer material has melted, its adhesion to the fibers is substantially improved, which leads to a significantly prolonged durability of the product performance on the paper machine.
  • the first polymer material has in addition to the function of stiffening the layer of fiber material, the task of improving the adhesion of the second polymer material to the fibers.
  • a preferred embodiment of the invention provides that in measure b) at least some of the fibers of the at least one fiber layer at fiber crossing and / or fiber contact points through the first Polymermateial be glued together.
  • the measure b) preferably comprises the introduction of an aqueous dispersion of particulate, in particular finely particulate, first polymer material into the at least one layer of fiber material and the removal of liquid from the dispersion introduced in the at least one fiber layer.
  • the fibers of the at least one fiber layer covering film substantially, in particular completely, is formed by the liquid is withdrawn from the particulate polymer dispersion and the polymer particles form a film forming on the fibers.
  • the surface can then be influenced in its topography in such a way that it assumes a configuration advantageous for the design of the web product to be produced thereon.
  • it is preferable to smooth the web material contact side e.g. by calendering. Therefore, a further embodiment of the method according to the invention provides in particular that after measure c) the web material contact side of the strip is processed in a further measure using pressure and / or temperature, in particular smoothed and / or compacted.
  • Another development of the invention provides that the at least one layer of fiber material with the first and the second polymer material after measure c) is compressed in a further measure using pressure and / or temperature. As a result, precompaction of this layer is achieved.
  • At least 50% of the particles of the fine particulate first polymer material have a size in the range from 2.0 nm to 10 ⁇ m. It is conceivable in this connection that all particles of the finely particulate first polymer material have a size of not more than 10 .mu.m, in particular of not more than 2 .mu.m.
  • a preferred embodiment of the invention provides that the measure b) is carried out a number of times to provide a multilayer or multi-layered fiber of the at least one layer of fiber material covering film.
  • the measure b) is carried out a number of times to provide a multilayer or multi-layered fiber of the at least one layer of fiber material covering film.
  • the fibers of the at least one layer of fiber material are coated with different first polymer material.
  • the measure c) comprises the introduction of the second polymer material in particle form in preferably aqueous dispersion in the at least one layer of fiber material and the melting of the introduced in the least one fiber layer second polymer material in particle form.
  • the permeable composite structure comprising the second polymer material is formed by melting the second polymer material after its introduction into the at least one layer of fibrous material, adhering to the fibers, and subsequently solidifying the melted second polymeric material to the fibers.
  • liquid may be preferably withdrawn from the at least one layer of fibrous material prior to the melting of the particulate second polymer material.
  • the first and second particulate polymeric material comprises an elastomer, in particular, the first and second particulate polymeric material is an elastomer.
  • the elastomer may in particular be polyurethane.
  • the first polymer material in particle form may have a smaller particle size than the second polymer material in particle form.
  • the particulate first polymer material used in measure b) has a higher melting point than that in measure c). used particulate second polymer material.
  • the measure a) may include fixing, preferably needling, the at least one layer of fiber material to a support structure. It is conceivable in this connection that the bonding of the at least one layer of fibrous material to the support structure takes place prior to the application of the first and second polymer material or, alternatively, first the first and the second polymer material is applied to the at least one layer of fibrous material before Connect this with the Carrying structure takes place.
  • the support structure may be fabric-like or random. It is also conceivable in this connection that the carrying structure comprises or is formed from a one-piece polymeric lattice structure, as is the case for example in the US Pat EP0285376 is described. In general, any textile surface structure which is suitable as a load-bearing support structure is conceivable.
  • the at least one layer of fiber material may be formed in particular as a nonwoven layer.
  • the measure c) can be carried out after the measure b).
  • the Fig. 1 shows in a pregnant foodsphase in section a belt 10, as it can be used for example in a press section of a paper machine.
  • the band 10 comprises a support structure 12, which may be formed, for example, as a fabric, as a scrim or as a spiral link structure.
  • a layer 16 of fiber material On a machine contact side 14 of the support structure 12 may be provided a layer 16 of fiber material, which may be connected to the support structure 12, for example by needling.
  • a layer 20 and a layer 40 of fiber material is provided in the illustrated example. These are also firmly connected to the support structure 12 preferably by needling.
  • the fibers of the two layers 20 and 40 are coated with a first polymer material forming a film.
  • the first polymer material forming the film can also completely or partially coat the layers 12 and 16.
  • a plurality of fine particles 22 of the first polymer material is applied in the layer 20 of fiber material. These particles 22 preferably spread over the entire thickness of the layer 20 of fiber material. This can be done so that an aqueous dispersion of fine particulate first polymer material 22 is applied with a weight fraction of about 2 to 10% of the particles 22 from the web material contact side 18 of the tape ago in the layer 20.
  • the liquid is removed from the layers 20, 40 and 16 of fiber material and also the support structure 12, for example by evaporation, whereby a fiber of these layers at least partially coating film forms.
  • This process of introducing a film-forming first polymer material, the drying and film-forming process and thus the coating and partially bonding, or embedding of the fibers can be repeated several times, so that forms a corresponding multilayer coating on the fibers.
  • the materials used for this purpose may differ, for example, from film layer to film layer.
  • a second particulate polymer material may be introduced whose particles are then dimensioned, for example, such that at least 50% of the Total volume of all particles thereof have a size in the range of 20 microns to 120 microns. These particles will be distributed in accordance with the porosity of the layer 20 from already coated fiber material in the inner volume area, which due to the generally larger particles this increases in the near-surface region, i. in the region of the web material contact side 18, accumulate. If necessary, smaller particles can penetrate deeper into the overall structure (layers 20, 12, 16).
  • the second polymer material forming the permeable layer preferably has a lower melting point than the first polymeric material with which the fibers of the layer 20 of fiber material have been coated, heating to only a temperature which will melt the remaining second particulate polymer material is required but the first film-forming polymeric material of the fiber coating does not interfere. This creates a strong connection between the two materials.
  • the proportion of this second polymer material forming a coherent polymeric structure is preferably in the range from 20 g / m 2 to 400 g / m 2 .
  • the tensile strength of the second polymer material used is preferably in the range between 5 and 1000 MPa, and this polymer material should have a melting point in the range between 120 ° C and 220 ° C.
  • Polymer dispersions preferably based on polyurethane or polyacrylate, but also other or mixtures of several polymer dispersions, such as, for example, Impranil DLH or Witcobond 372-95 or any similar material having properties in comparable ranges, may preferably be used to provide the film of the first polymer material be used.
  • the tensile strength of the first polymer materials formed from the polymer dispersions may be in the range of 1 to 100 MPa, and the maximum elongation may be in the range of 100 to 1600%.
  • the fine particulate first particulate material is preferably applied in an amount ranging from 20 to 500 g / m 2 .
  • these materials are applied so that they are preferably applied from the web material contact side in preferably aqueous dispersion, so that the particles can be distributed in the inner volume region of the layer of fiber material.
  • at least 50% of the particles of the first polymer material should have a size in the range of 2 nm - 10 microns.
  • thermoplastic polymeric materials preferably elastic materials such as e.g. Polyurethanes find use.
  • This can e.g. Polyurethanes as under the trade name Estane, Pearlcoat, Unex, etc. are available and have the required material properties.
  • polyether block polyamides e.g. Pebax ex Arkema
  • polyamides e.g. B. PA11, PA12, PA6, 12, which is e.g. under the trade names Orgasol or Rilsan, or similar.
  • high melt flow materials or material mixtures are used.
  • the second polymer material is preferably used in powder form and preferably applied as an aqueous dispersion.
  • dispersants and thickeners can be used.
  • the second polymer material can also be applied dry, for example, by sprinkling.
  • the first polymer material forming the film e.g. a spraying process, patting, padding, etc are used
  • the aforementioned methods as well as thermal application methods can be used.
  • the film-forming coating of the fiber material is also conceivable by means of polymer solutions.
  • the principles of the invention may find application when employing multiple layers of fibrous material. It is also possible to carry out the described measures, that is to say the coating of the fibers and the formation of the permeable composite structure, in one operation.
  • the coarser particles accumulate primarily on the surface of the fibers.
  • a polymer film forms on the fibers, which additionally bonds the coarser particles.
  • the second polymer material forming the permeable layer is preferably lower in melting point than the polymer material with which the fibers of the layer 20 of fiber material have been coated, heating is only required to a temperature which, while melting the remaining second particulate material the material of the fiber coating is not affected and leads to a strong connection of both materials.
  • the Fig. 2 shows in a schematic enlarged view of the fiber structure of the layer 20 of fiber material thereof.
  • Fig. 2 individual fibers 26 coated with a film 28 of the first polymeric material.
  • the fibers 26 are reinforced by this film coating 28.
  • a bond is created by the film 28 at the intersections of the fibers 26, so that also the total strength of the layer 20 of fibrous material increases.
  • the permeable polymeric structure 30 forming second polymer material, which mainly accumulates in the region of intersections or in the vicinity of the already coated with the film 28 fibers 26 after it has been melted and cooled again. Between the fibers 26 and the polymer material regions 28, 30 are the pores or cavities 32, which allow the passage of liquid through the layer 20.
  • the Fig. 3 shows in cross-section an electron micrograph of an inventive formed as a press felt belt 10th
  • the belt 10 has a layer of fiber material 20 with fibers 26 providing the web material contact side 18.
  • the machine contact side 14 of the belt 10 is formed by a layer of fiber material 16.
  • a support structure 12 in the form of a fabric 12 is arranged.
  • the two layers of fiber material 16 and 20 and the fabric 12 are connected by needling firmly together.
  • the fibers 26 of the layer 20 are substantially completely coated with the film 28 formed from the first polymeric material.
  • the Fig. 4 and 5 show the plan view of the web material contact surface 22 of such a layer 20 of polymeric material. It can be seen the fiber structure and the surrounding structure-forming polymeric material and a variety of pores. With this patterning, not only an increased strength and recovery property of the fibrous material layer 20 is achieved. The microstructuring and optionally the surface energy of the introduced polymer material on the surface also facilitates the release of such a band where it is to be separated from the web material to be produced.

Landscapes

  • Laminated Bodies (AREA)
EP08161414A 2007-12-21 2008-07-30 Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande Withdrawn EP2072670A1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US1580407P 2007-12-21 2007-12-21

Publications (1)

Publication Number Publication Date
EP2072670A1 true EP2072670A1 (fr) 2009-06-24

Family

ID=40467064

Family Applications (1)

Application Number Title Priority Date Filing Date
EP08161414A Withdrawn EP2072670A1 (fr) 2007-12-21 2008-07-30 Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande

Country Status (1)

Country Link
EP (1) EP2072670A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8496785B2 (en) 2009-08-04 2013-07-30 Voith Patent Gmbh Combination of a press felt with a pressure roll covering and/or suction roll covering for a paper machine

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4439481A (en) * 1983-03-04 1984-03-27 Albany International Corp. Resole treated papermakers felt and method of fabrication
EP0285376A2 (fr) 1987-03-31 1988-10-05 Leonard Robert Lefkowitz Etoffe non tissée et son procédé de fabrication
WO2003091498A1 (fr) * 2002-04-26 2003-11-06 Tamfelt Oyj Abp Feutre de presse

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4439481A (en) * 1983-03-04 1984-03-27 Albany International Corp. Resole treated papermakers felt and method of fabrication
EP0285376A2 (fr) 1987-03-31 1988-10-05 Leonard Robert Lefkowitz Etoffe non tissée et son procédé de fabrication
WO2003091498A1 (fr) * 2002-04-26 2003-11-06 Tamfelt Oyj Abp Feutre de presse

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8496785B2 (en) 2009-08-04 2013-07-30 Voith Patent Gmbh Combination of a press felt with a pressure roll covering and/or suction roll covering for a paper machine
EP2462279B1 (fr) 2009-08-04 2016-08-31 Voith Patent GmbH Combinaison d'un feutre de presse avec un revêtement de cylindre compresseur et/ou un revêtement de cylindre aspirant pour une machine à papier

Similar Documents

Publication Publication Date Title
DE69709115T2 (de) Verwendung eines filzes mit einer membran in einer yankee-papiermaschine
EP1722034B1 (fr) Toile ou feutre comprenant des fibres qui peuvent se scinder
DE69533498T2 (de) Verfahren zum Schliessen des Saums von Überführungs- und anderen Papierbehandlungsbändern
DE69718572T2 (de) Faserverstärkter Kunststoff mit Verbundsubstrat
EP2072675A2 (fr) Bande pour une machine destinée à la fabrication de matériau en bande
DE60121015T2 (de) Pressfilz für papiermaschine
US8034730B2 (en) Composite press fabric
DE602005004963T2 (de) Papiermacherfilz mit punktuell gebundener Zwischenschicht aus Fasern geringer Feinheit
EP2072676A1 (fr) Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande
EP3443162B1 (fr) Feutre de presse et procédé pour sa fabrication
DE29706427U1 (de) Biegsames Band, insbesondere zum Einsatz in Papiermaschinen
EP2344696A2 (fr) Feutre de presse et son procédé de fabrication
EP2072667A1 (fr) Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande
DE102007000578A1 (de) Papiermaschinenbespannungen, insbesondere für Pressfilze, und Verfahren zu deren Herstellung
EP2072670A1 (fr) Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande
EP2072669B1 (fr) Bande pour une machine destinée à la fabrication de matériaux en bande et procédé de fabrication d'une telle bande
EP2128334A1 (fr) Feutre de presse
US7981820B2 (en) Press fabric for a machine for the production of web material and method to produce said press fabric
DE60320384T2 (de) Band für papiermaschinen
WO2015090797A1 (fr) Revêtement et procédé pour le produire
AT11147U1 (de) Maschine zur herstellung von bahnmaterial
DE102004038770A1 (de) Papiermaschinenbespannungen
DE102007055690A1 (de) Papiermaschinenbespannung
EP3443160B1 (fr) Toile de formation et son procédé de fabrication
EP2185769A1 (fr) Feutre comprimé

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

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL BA MK RS

17P Request for examination filed

Effective date: 20091228

17Q First examination report despatched

Effective date: 20100122

AKX Designation fees paid

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20150310