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Publication numberUS20040259449 A1
Publication typeApplication
Application numberUS 10/489,057
PCT numberPCT/EP2002/009624
Publication dateDec 23, 2004
Filing dateAug 29, 2002
Priority dateSep 10, 2001
Also published asCA2459901A1, CN1304686C, CN1553980A, DE10144307A1, DE50208019D1, EP1432869A1, EP1432869B1, WO2003023136A1
Publication number10489057, 489057, PCT/2002/9624, PCT/EP/2/009624, PCT/EP/2/09624, PCT/EP/2002/009624, PCT/EP/2002/09624, PCT/EP2/009624, PCT/EP2/09624, PCT/EP2002/009624, PCT/EP2002/09624, PCT/EP2002009624, PCT/EP200209624, PCT/EP2009624, PCT/EP209624, US 2004/0259449 A1, US 2004/259449 A1, US 20040259449 A1, US 20040259449A1, US 2004259449 A1, US 2004259449A1, US-A1-20040259449, US-A1-2004259449, US2004/0259449A1, US2004/259449A1, US20040259449 A1, US20040259449A1, US2004259449 A1, US2004259449A1
InventorsThierry Onder de Linden, Jurgen Budenbender
Original AssigneeOnder De Linden Thierry, Jurgen Budenbender
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Backing fabrics for papermaking machine convering materials
US 20040259449 A1
Abstract
Backing fabric for paper machine felts, based on yarn made of polyamide 6 and polyamide 6.10, polyamide 6.11, polyamide 11 and/or polyamide 12.
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Claims(8)
1. Backing fabric for papermaking machine covering materials, having a base fabric which comprises combination twisted yarns of monofilaments of polyamide 6 and monofilaments of polyamide 6.10, in the warp direction.
2. Backing fabric for papermaking machine covering materials, having a base fabric which comprises combination twisted fabrics of monofilaments of polyamide 6 and monofilaments of polyamide 6.12, polyamide 11 or polyamide 12 in the warp direction.
3. Backing fabric according to claim 1, wherein the twisted yarns contain 1 to 20 monofilaments of polyamide 6 and 20 to 1 monofilaments of polyamide 6.10.
4. Backing fabric according to claim 2, wherein the twisted yarns contain 1 to 20, monofilaments of polyamide 6 and 20 to 1 monofilaments of polyamide 6.12, polyamide 11 or polyamide 12.
5. Backing fabric according to any one of claims 1 to 4, wherein said monofilaments of said base fabrics have a diameter of 0.08 to 0.3 mm.
6. Process for the production of base fabrics of papermaking machine covering materials, which comprises forming a combination twisted yarn of polyamide 6 monofilaments with monofilaments of polyamide 6.10, polyamide 6.12, polyamide 11 or polyamide 12 and forming the warp of a base fabric with said combination twisted yarn.
7. Backing fabric according to claim 3, wherein said twisted yarns contain 1 to 6 monofilaments of polyamide 6 and 6 to 1 monofilaments of polyamide 6.10.
8. Backing fabric according to claim 4, wherein said twisted yarns contain 1 to 6 monofilaments of polyamide 6 and 6 to 1 monofilaments of polyamide 6.12, polyamide 11 or polyamide 12.
Description
  • [0001]
    The present invention relates to backing fabrics for papermaking machine felt with improved properties, preferably improved wear resistance and in particular improved dimensional stability during paper manufacture.
  • [0002]
    Processes for the production of monofilaments from thermoplastic polymers are in principle known (c.f. Handbuch der Kunststofftechnik II, C. Hanser Verlag, Munich 1986, pp. 295-319).
  • [0003]
    Paper production on modern papermaking machines involving sheet forming (forming part), mechanical dewatering (pressing part) and thermal dewatering (drying part), smoothing and rolling is known from Lehrbuch der Papier- und Kartonerzeugung (VEB Fachbuchverlag 1987, p. 190 ff).
  • [0004]
    Fabrics employed in the forming part consist predominantly of polyester monofilaments. In order to improve the abrasion resistance monofilaments of polyamides together with polyester monofilaments in an alternating pick-and-shot arrangement on the machine side are also used.
  • [0005]
    In the pressing part the basic fabrics for the pressing felt or wet pressing felt are produced almost exclusively from polyamide fibres and polyamide monofilaments, preferably from pure polyamide-6 but also from polyamide-66. A nonwoven layer of polyamide fibres is needled onto the base fabrics consisting of polyamide monofilaments in a second processing stage and this layer is thereby mechanically anchored in the said base fabric.
  • [0006]
    Dry screens on the other hand normally consist of polyester monofilaments that are largely stabilised by means of suitable products, for example Stabaxol (a commercial product available from Rheinchemie, Mannheim), against hydrolytic decomposition.
  • [0007]
    The commercially available press felts made from polyamide-6 monofilaments have on account of their high abrasion resistance, compressibility and very good recovery of the felts after passing through the press nip major advantages compared to press felts of other materials, e.g. polypropylene, polyester, wool or other types of polyamide (e.g. PA 6.10, PA 6.12).
  • [0008]
    A significant disadvantage of these press felts is however the lack of dimensional stability in the event of machine downtimes. The materials polyamide-6 and polyamide-66 absorb up to 10 wt. % of water in a wet environment. The length and thickness of the monofilaments changes with the absorption of water. In particular the change in length means that in the event of malfunctions or downtimes of the papermaking machine due to other causes the felts have a different weight and fabric density in the wet zones than in the dry zones. After dealing with the malfunctions and starting up the papermaking machine again no high-quality paper can be produced with these felts until the felts have re-established the same water content and the same density and width over the whole area.
  • [0009]
    Furthermore the change in width often means that the full working width of the papermaking machine cannot be utilised since the felts extend beyond the maximum width of the machine and are damaged at their edges.
  • [0010]
    There has therefore been no lack of attempts to improve the dimensional stability of press felts in wet/dry cycles.
  • [0011]
    One possibility is to use other fabric constructions.
  • [0012]
    The use of other materials in the warp of the fabrics is widespread, for example the replacement of polyamide-6 or polyamide-66 monofilaments by filaments which absorb substantially less moisture under high ambient moisture conditions and in which the dimensions of the fabrics consequently change only slightly. Monofilaments of polyamide 6.10 and polyamide 6.12 have proved suitable.
  • [0013]
    A disadvantage of these fabrics and of the felt produced therefrom is however the significantly reduced wear resistance when used in papermaking machines compared to fabrics of polyamide-6 monofilaments and felts produced therefrom.
  • [0014]
    It has now surprisingly been found that the disadvantages of the lack of wear resistance can be avoided and can be replaced by the advantages of a good dimensional stability if the warp of the basic fabric consists of combination twisted yarns that contain monofilaments of polyamide-6 as well as also monofilaments of polyamide 6.10 or polyamide 6.12.
  • [0015]
    The object of the invention is achieved if in the production of the backing fabric there are used combination twisted yarns with 1 to 20 monofilaments of polyamide-6 and 20 to 1 monofilaments of polyamide 6.10, polyamide 6.12, polyamide 11 or polyamide 12 in the warp instead of twisted yarns of polyamide-6 monofilaments.
  • [0016]
    Moreover, the fabrics produced in this way also have a significantly improved economic utility since the raw materials polyamide-6 and polyamide-66 are industrially more readily available and can be re-used in many recycling systems after economic utilisation.
  • [0017]
    A particular advantage of the process according to the invention is that twisted yarns of an even number of the materials used as well as also an odd number of these materials can be twisted with one another. In this way specific, calculable dimensional changes of the twisted yarns or fabrics produced therefrom can be established and the economic utility can optionally also be improved.
  • [0018]
    The following examples demonstrate the advantages according to the invention of the combination twisted yarns, without restricting the possibilities of these combinations.
  • EXAMPLES
  • [0019]
    [0019]
    Monofilament
    Commercial Product Diameter
    Polyamide 6 X 201 0.20 mm
    Polyamide 6.10 ATF 2311 0.20 mm
    Polyamide 6.12 ATF 23 0.20 mm
  • [0020]
    Manufacturer: Bayer Faser GmbH
  • [0021]
    Pre-Twisted Yarns
  • [0022]
    Pre-twisted yarns of construction 0.20 mm×2 were produced on an Allma Saurer AZB-T type yarn twisting machine at 304 revolutions/metre
  • [0023]
    Experimental part V 1: X 201/X 201, 0.20 mm×2, S 304 revolutions/metre
  • [0024]
    Experimental part V 2: X 201/ATF 2311, 0.20 mm×2, S 304 revolutions/metre
  • [0025]
    Experimental part V 3: ATF 2311, 0.20 mm×2, S 304 revolutions/metre
  • [0026]
    Experimental part V 4: ATF 2300 0.20 mm×2, S 304 revolutions/metre
  • Comparison Example 1
  • [0027]
    Pre-twisted yarns of polyamide 6, experimental part V 1, were processed on an Allma Saurer AZB-T type yarn twisting machine to form a balanced annular twisted yarn of construction 0.2 mm×2×2 with S 304/Z 260 revolutions.
  • [0028]
    The twisted yarn was then fixed tension-free in a heating cabinet for 5 minutes at 160° C. and cut into pieces of length 1.00 m. The exact length and the weight of the sample pieces was determined. Following this the samples were then stored tension-free for 24 hours in a water bath at 20° C., removed from the water, dried, and the change in length as well as the weight were determined.
  • [0029]
    The twisted yarn was then dried for 24 hours at 80° C. in a circulating air drying cabinet and the change in length and weight loss were again determined. This cycle was repeated three times. The changes in length between the wet/dry cycles are summarised in Table 1.
  • [0030]
    The abrasion resistance of the twisted yarns was determined by an abrasion test developed in-house. For this, the monofilaments and twisted yarns are drawn cyclically under a defined load over a grinding roller until they break. The number of grinding cycles is a measure of the abrasion resistance.
  • Comparison Example 2
  • [0031]
    Pre-twisted yarns of polyamide 6.10 (ATF 2311), experimental part V 3, 0.20 mm were processed into an annular twisted yarn as described in comparison example 1. The change in length after wet/dry alternating cycles as well as the abrasion resistance were also determined as described in comparison example 1. The results are summarised in Table 1.
  • Example 1
  • [0032]
    Pre-twisted yarn V 1 and pre-twisted yarn V 2 were processed into an annular twisted yarn as described in comparison example 1. The annular twisted yarn had a proportion of PA 6.10 of 25%. The change in length after wet/dry alternating cycles as well as the abrasion resistance was also determined as described in comparison example 1. The results are summarised in Table 1.
  • Example 2
  • [0033]
    Pre-twisted yarn V 1 and pre-twisted yarn V 3 were processed into an annular twisted yarn as described in comparison example 1. The annular twisted yarn had a proportion of PA 6.10 of 50%. The change in length after wet/dry alternating cycles as well as the abrasion resistance was also determined as described in comparison example 1. The results are summarised in Table 1.
  • Example 3
  • [0034]
    Pre-twisted yarn V 2 and pre-twisted yarn V 2 were processed into an annular twisted yarn as described in comparison example 1. The annular twisted yarn had a proportion of PA 6.10 of 50%. The change in length after wet/dry alternating cycles as well as the abrasion resistance was also determined as described in comparison example 1. The results are summarised in Table 1.
  • Example 4
  • [0035]
    Pre-twisted yarn V 3 and pre-twisted yarn V 2 were processed into an annular twisted yarn as described in comparison example 1. The annular twisted yarn had a proportion of PA 6.10 of 75%. The change in length after wet/dry alternating cycles as well as the abrasion resistance was also determined as described in comparison example 1. The results are summarised in Table 1.
  • Example 5
  • [0036]
    Pre-twisted yarn V 4 and pre-twisted yarn V 1 were processed into an annular twisted yarn as described in comparison example 1. The annular twisted yarn had a proportion of PA 6.12 of 50%. The change in length after wet/dry alternating cycles as well as the abrasion resistance was also determined as described in comparison example 1. The results are summarised in Table 1.
    TABLE 1
    Abrasion
    Propn. Propn. Water Water Behaviour
    PA 6 PA 6.10 Absorption 1) Elongation 1) min-max
    % % % % Cycles
    Comp. Ex. 1 100 0 6.8 3.0 260-350
    Comp. Ex. 2 0 100 2.8 1.2 220-290
    Example 1 75 25 6.0 2.7 260-320
    Example 2 50 50 5.2 2.0 250-295
    Example 3 50 50 4.9 1.9 255-305
    Example 4 25 75 3.8 1.6 225-290
    Propn.
    PA 6.12
    Example 5 50 50 5.1 2.1 245-300
Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US4564985 *Oct 7, 1982Jan 21, 1986Nippon Felt Co., Ltd.Felt for paper manufacture and method for producing the same
US4874660 *Apr 14, 1988Oct 17, 1989Albany Research (Uk) LimitedPaper machine felts
US4891040 *Jul 20, 1988Jan 2, 1990Mitsuboshi Belting Ltd.Woven fabric belt
US5164251 *Nov 28, 1990Nov 17, 1992Albany International Corp.Paper machine felts
US5194121 *Nov 29, 1989Mar 16, 1993Nippon Felt Co. Ltd.Needled felt for papermaking use
US5244543 *Jan 14, 1992Sep 14, 1993Asten Group, Inc.Belt filter press fabric
US5783501 *Oct 10, 1994Jul 21, 1998Ems-Inventa AgPaper machine felts
US6175996 *Jul 22, 1999Jan 23, 2001Weavexx CorporationMethod of forming a papermakers' felt
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7344074 *Apr 8, 2002Mar 18, 2008Nokia CorporationMobile terminal featuring smart card interrupt
US8289159Apr 24, 2007Oct 16, 2012Qualcomm IncorporatedWireless localization apparatus and method
US8406794Apr 25, 2007Mar 26, 2013Qualcomm IncorporatedMethods and apparatuses of initiating communication in wireless networks
US8600373Apr 26, 2007Dec 3, 2013Qualcomm IncorporatedDynamic distribution of device functionality and resource management
US8644396Apr 17, 2007Feb 4, 2014Qualcomm IncorporatedWaveform encoding for wireless applications
US8654868Apr 17, 2007Feb 18, 2014Qualcomm IncorporatedOffloaded processing for wireless applications
US20100188695 *Jan 12, 2010Jul 29, 2010Sharp Kabushiki KaishaCommunication system, information processing system, image forming apparatus and portable information terminal device
Classifications
U.S. Classification442/181
International ClassificationD03D15/00, D21F7/08, D03D7/00
Cooperative ClassificationY02W30/62, Y10T442/30, D21F7/08, B29B17/00, D10B2211/02, D03D7/00, D10B2331/02, B29L2031/7092, B29K2277/00, D10B2331/04
European ClassificationD21F7/08, D03D7/00
Legal Events
DateCodeEventDescription
Aug 16, 2004ASAssignment
Owner name: BAYER FRASER GMBH, GERMANY
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ONDER DE LINDEN, THIERRY;BUDENBENDER, JURGEN;REEL/FRAME:015062/0308;SIGNING DATES FROM 20040224 TO 20040322