GB1562284A - Papermakers - Google Patents

Papermakers Download PDF

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Publication number
GB1562284A
GB1562284A GB44800/75A GB4480075A GB1562284A GB 1562284 A GB1562284 A GB 1562284A GB 44800/75 A GB44800/75 A GB 44800/75A GB 4480075 A GB4480075 A GB 4480075A GB 1562284 A GB1562284 A GB 1562284A
Authority
GB
United Kingdom
Prior art keywords
yarns
fabric
polyester
polyamide
machine direction
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
Application number
GB44800/75A
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.)
Scapa Blackburn Ltd
Original Assignee
Scapa Porritt Ltd
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 Scapa Porritt Ltd filed Critical Scapa Porritt Ltd
Priority to GB44800/75A priority Critical patent/GB1562284A/en
Priority to ZA766250A priority patent/ZA766250B/en
Priority to NZ182387A priority patent/NZ182387A/en
Priority to JP12788676A priority patent/JPS5285503A/en
Priority to IT28718/76A priority patent/IT1068852B/en
Priority to AU19014/76A priority patent/AU498904B2/en
Priority to CH1356876A priority patent/CH616469A5/de
Priority to NO763679A priority patent/NO147803B/en
Priority to NLAANVRAGE7611946,A priority patent/NL183202B/en
Priority to SE7612079A priority patent/SE7612079L/en
Priority to BR7607275A priority patent/BR7607275A/en
Priority to AT804876A priority patent/AT349879B/en
Priority to BE171963A priority patent/BE847837A/en
Priority to CA264,431A priority patent/CA1059354A/en
Priority to FI763099A priority patent/FI66040B/en
Priority to FR7632912A priority patent/FR2329799A1/en
Priority to DE19762649312 priority patent/DE2649312A1/en
Priority to ES452907A priority patent/ES452907A1/en
Priority to US06/109,661 priority patent/US4289173A/en
Publication of GB1562284A publication Critical patent/GB1562284A/en
Priority to US06/290,007 priority patent/US4529013A/en
Expired legal-status Critical Current

Links

Classifications

    • D—TEXTILES; PAPER
    • D03—WEAVING
    • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
    • D03D15/00—Woven fabrics characterised by the material, structure or properties of the fibres, filaments, yarns, threads or other warp or weft elements used
    • 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
    • D—TEXTILES; PAPER
    • D03—WEAVING
    • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
    • D03D15/00—Woven fabrics characterised by the material, structure or properties of the fibres, filaments, yarns, threads or other warp or weft elements used
    • D03D15/20—Woven fabrics characterised by the material, structure or properties of the fibres, filaments, yarns, threads or other warp or weft elements used characterised by the material of the fibres or filaments constituting the yarns or threads
    • D03D15/283—Woven fabrics characterised by the material, structure or properties of the fibres, filaments, yarns, threads or other warp or weft elements used characterised by the material of the fibres or filaments constituting the yarns or threads synthetic polymer-based, e.g. polyamide or polyester fibres
    • 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
    • D—TEXTILES; PAPER
    • D10—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
    • D10B—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
    • D10B2331/00—Fibres made from polymers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polycondensation products
    • D10B2331/04—Fibres made from polymers obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polycondensation products polyesters, e.g. polyethylene terephthalate [PET]

Description

(54) PAPERMAKERS FABRICS (71) We, SCAPA-PORRITT LIMITED, a British Company of Cartmell Road, Blackburn, Lancashire, BB2 2SZ, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following state ment: - The invention concerns papermakers fabrics, and has more particular reference to what are known in the art as "wet end" fabrics, that is to say drainage fabrics, such as fourdrinier wires, which are endless bands of openwork mesh structure intended to support a moisture laden web of cellulosic fibres.
Originally fourdrinier wires comprised structures woven from metal wires, the preferred material of choice being phosphor bronze.
In recent years synthetic yarns have been widely used in the production of papermakers fabrics, including drainage fabrics for the wet end of the papermaking machine, but the inherent characteristics of the synthetic yarns in the context in question has given rise to some difficulties. Thus, in the case of polyester yarns, there is the problem of wear, whilst in the case of polyamides, there is the difficulty of dimensional instability in account of moisture take-up.
The use of a coating to improve the wear resistance of a wet end fabric formed from polyester yarns has been proposed.
It has also been proposed to overcome the problem of dimensional instability of polyamide yarns, and render such yarns suitable for application in the context of wet end fabrics by applying a resin coating to a multifilament yarn, the polyamide being totally unacceptable in its untreated state.
The object of the present invention is to provide a wet end fabric of adequate wear resistance and dimensional stability without the need to apply a coating for such purposes.
Thus, according to the present invention, we propose a papermakers wet end drainage fabric which is an endlesss band of openwork mesh structure and which comprises a woven structure having yarns formed wholly from polyester material extending in at least one direction so as to impart dimensional stability in at least the or each direction in which such yarns extend, characterised in that said woven structure also includes further yarns formed wholly from a synthetic material different from and of greater wear resistance than said polyester material of the first said yams, said further yarns being separate from and extending in a common direction to the first said yams.
With this arrangement it has been found possible to achieve, unexpectedly, improved wear resistance whilst maintaining dimensional stability without requiring the yarns to be coated.
The inherent dimensional stability of the polyester yarns is not, as might be expected, offset by any instability of the other yarns.
Preferably, the said further yarns constitute no more than 500,( of the yarns in the or each direction in which they extend, the remaining yarns in such direction all being the first said yarns, and in particular 50% of the yarns may be the further yarns.
In a particularly preferred embodiment the said further yarns are interposed between the first said yarns, and the said further yarns and the first said yarns may be arranged alternately.
Alternatively, or additionally the fabric may have at least two layers of common direction yarns comprising an upper layer of the first said yarns and a lower layer of the said further yarns or vice versa. In particular, the upper layer may be formed wholly of the first said yarns and the lower layer wholly of the further yarns.
The first said yarns are dimensionally stable polyester yarns such as are conventionally used in papermaking fabrics, that is yarns formed from polyester of the polyethylene terephthalate kind as sold for example under the Trade Mark Terylene or Trevira.
The further yarns may be any suitable material such as polyamide, polyolefin, poly tetrafluoroethylene, or even a polyester material different from that of the first said yarns (such as polybutyl terephthalate) having the requisite properties. A polyamide, particularly a polyamide as sold under the Trade Mark Nylon, is preferred.
Comparative tests between a standard fabric woven wholly from monofilament polyester yarns and an equivalent fabric woven partly from polyester (Terylene) and partly from polyamide yarns (Nylon 6), in accordance with one embodiment of the present invention, show the increase in wear resistance to be significant, and so much so that either an equivalent fabric of corresponding drainage characteristics can be provided which has an improved service life, or alternatively a finer fabric of improved drainage characteristic and a like service life can be produced.
In carrying out the tests, the following procedure was adopted: A sample forming fabric was held, under tension, in contact with the upper part of the periphery of a disc rotating in a vertical plane, whilst a slurry of a material commonly used in the papermaking art and having abrasive characteristics was continuously applied to the outer surface of the fabric.
The thickness of the sample was measured initially, and again after a predetermined time.
The disc was rotated at the same speed, the tension applied to the sample remained constant and the slurry was applied at a constant rate throughout the tests.
The control sample comprises a woven fabric having monofilament yarns both in machine direction and cross-machine direction, there being 26 machine direction ends and 20 cross-machine direction yarns of monofilament polyester yarns of 0.25 mm diameter per centimetre, whilst in the polyester/polyamide sample the cross-machine direction yarns comprised alternate polyester and polyamide monofilament yams, the weave structure in the two samples being the same.
The abrasive material used was calcium carbonate.
The following results were obtained: Thickness in (mm) Time in Control Polyester/Polyamide Minutes Sample Sample 0 0.55 0.55 40 0.37 0.46 The test results suggest that the wear resistance of the fabric having the polyester/ polyamide cross-machine direction yarns is improved as compared with the control sample which is wholly of polyester yarns.
It is to be understood that if the machine direction yarns of the fabric are ordinarily to be expected to be subjected to the wear, then the polyester/polyamide combination will be applied to the machine direction yarns rather than to the cross-machine direction yarns.
In those instances where wear both to machine and cross-machine direction yarns is experienced a polyester/polyamide combination will be provided in both directions.
The invention is, of course, not restricted to alternate machine or cross-machine direction polyester and polyamide yarns, since other fabric structures may well be of utilisation.
Whilst one preferred arrangement has been described in which there are 50',', of said further yarns, in alternative embodiments there may be a different proportion of further yarns. Thus, there may be up to 60,!, further yarns particularly but in the case of a tubular weave, and there may be more or less than 50 ,., where this is desirable or neces- sary due to the weaving pattern used.
WHAT WE CLAIM IS: 1. A papermaker's wet end drainage fabric which is an endless band of openwork mesh structure and which comprises a woven structure having yarns formed wholly from polyester material extending in at least one direction so as to impart dimensional stability in at least the or each direction in which such yarns extend, characterised in that said woven structure also includes further yarns formed wholly from a synthetic material different from and of greater wear resistance than said polyester material of the first said yarns, said further yarns being separate from and extending in a common direction to the said yarns.
2. A fabric according to claim 1, wherein the said further yarns constitute no more than 50% of the yarns in the or each direction in which they extend, the remaining yarns in such direction all being the first said yams.
3. A fabric according to claim 2, wherein 50% of the yarns are the said further yarns.
4. A fabric according to any one of claims 1 to 3, wherein the said further yarns are interposed between the first said yarns.
5. A fabric according to claim 4, when dependent on claim 3, wherein the said further yarns and the brst said yarns are arranged alternately.
6. A fabric according to any one of claims 1 to 3, which has at least two layers of common direction yarns comprising an upper layer of the first said yarns and a lower layer of the said further yarns.
7. A fabric according to claim 6, when dependent on claim 3, wherein the upper layer is formed wholly of the first said yarns
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

  1. **WARNING** start of CLMS field may overlap end of DESC **.
    particularly a polyamide as sold under the Trade Mark Nylon, is preferred.
    Comparative tests between a standard fabric woven wholly from monofilament polyester yarns and an equivalent fabric woven partly from polyester (Terylene) and partly from polyamide yarns (Nylon 6), in accordance with one embodiment of the present invention, show the increase in wear resistance to be significant, and so much so that either an equivalent fabric of corresponding drainage characteristics can be provided which has an improved service life, or alternatively a finer fabric of improved drainage characteristic and a like service life can be produced.
    In carrying out the tests, the following procedure was adopted: A sample forming fabric was held, under tension, in contact with the upper part of the periphery of a disc rotating in a vertical plane, whilst a slurry of a material commonly used in the papermaking art and having abrasive characteristics was continuously applied to the outer surface of the fabric.
    The thickness of the sample was measured initially, and again after a predetermined time.
    The disc was rotated at the same speed, the tension applied to the sample remained constant and the slurry was applied at a constant rate throughout the tests.
    The control sample comprises a woven fabric having monofilament yarns both in machine direction and cross-machine direction, there being 26 machine direction ends and 20 cross-machine direction yarns of monofilament polyester yarns of 0.25 mm diameter per centimetre, whilst in the polyester/polyamide sample the cross-machine direction yarns comprised alternate polyester and polyamide monofilament yams, the weave structure in the two samples being the same.
    The abrasive material used was calcium carbonate.
    The following results were obtained: Thickness in (mm) Time in Control Polyester/Polyamide Minutes Sample Sample 0 0.55 0.55
    40 0.37 0.46 The test results suggest that the wear resistance of the fabric having the polyester/ polyamide cross-machine direction yarns is improved as compared with the control sample which is wholly of polyester yarns.
    It is to be understood that if the machine direction yarns of the fabric are ordinarily to be expected to be subjected to the wear, then the polyester/polyamide combination will be applied to the machine direction yarns rather than to the cross-machine direction yarns.
    In those instances where wear both to machine and cross-machine direction yarns is experienced a polyester/polyamide combination will be provided in both directions.
    The invention is, of course, not restricted to alternate machine or cross-machine direction polyester and polyamide yarns, since other fabric structures may well be of utilisation.
    Whilst one preferred arrangement has been described in which there are 50',', of said further yarns, in alternative embodiments there may be a different proportion of further yarns. Thus, there may be up to 60,!, further yarns particularly but in the case of a tubular weave, and there may be more or less than 50 ,., where this is desirable or neces- sary due to the weaving pattern used.
    WHAT WE CLAIM IS: 1. A papermaker's wet end drainage fabric which is an endless band of openwork mesh structure and which comprises a woven structure having yarns formed wholly from polyester material extending in at least one direction so as to impart dimensional stability in at least the or each direction in which such yarns extend, characterised in that said woven structure also includes further yarns formed wholly from a synthetic material different from and of greater wear resistance than said polyester material of the first said yarns, said further yarns being separate from and extending in a common direction to the said yarns.
  2. 2. A fabric according to claim 1, wherein the said further yarns constitute no more than 50% of the yarns in the or each direction in which they extend, the remaining yarns in such direction all being the first said yams.
  3. 3. A fabric according to claim 2, wherein 50% of the yarns are the said further yarns.
  4. 4. A fabric according to any one of claims 1 to 3, wherein the said further yarns are interposed between the first said yarns.
  5. 5. A fabric according to claim 4, when dependent on claim 3, wherein the said further yarns and the brst said yarns are arranged alternately.
  6. 6. A fabric according to any one of claims 1 to 3, which has at least two layers of common direction yarns comprising an upper layer of the first said yarns and a lower layer of the said further yarns.
  7. 7. A fabric according to claim 6, when dependent on claim 3, wherein the upper layer is formed wholly of the first said yarns
    and the lower layer is formed wholly of the further yams.
  8. 8. A fabric according to any one of claims 1 to 7, wherein the said further yarns are polyamide yarns.
  9. 9. A fabric substantially as hereinbefore described by way of example only.
GB44800/75A 1975-10-30 1975-10-30 Papermakers Expired GB1562284A (en)

Priority Applications (20)

Application Number Priority Date Filing Date Title
GB44800/75A GB1562284A (en) 1975-10-30 1975-10-30 Papermakers
ZA766250A ZA766250B (en) 1975-10-30 1976-10-20 Papermakers fabrics
NZ182387A NZ182387A (en) 1975-10-30 1976-10-21 Woven paper-making fabric
JP12788676A JPS5285503A (en) 1975-10-30 1976-10-26 Fabric for paper making
IT28718/76A IT1068852B (en) 1975-10-30 1976-10-26 PAPER FABRICS
AU19014/76A AU498904B2 (en) 1975-10-30 1976-10-26 Papermakers fabric
CH1356876A CH616469A5 (en) 1975-10-30 1976-10-27
NO763679A NO147803B (en) 1975-10-30 1976-10-28 FORMING WIRE FOR A PAPER MACHINE.
NLAANVRAGE7611946,A NL183202B (en) 1975-10-30 1976-10-28 CLOTH FOR THE PAPER INDUSTRY.
SE7612079A SE7612079L (en) 1975-10-30 1976-10-29 TEXTILBANA FOR PAPER MACHINE, SPECIAL FOR THE WATER PART
BR7607275A BR7607275A (en) 1975-10-30 1976-10-29 TEXTURE FOR PAPER MANUFACTURING
AT804876A AT349879B (en) 1975-10-30 1976-10-29 FABRICS FOR PAPER MACHINE SCREENS
BE171963A BE847837A (en) 1975-10-30 1976-10-29 FABRICS FOR PAPER MANUFACTURING,
CA264,431A CA1059354A (en) 1975-10-30 1976-10-29 Papermakers fabrics
FI763099A FI66040B (en) 1975-10-30 1976-10-29 FORMNINGSVAEVNAD FOER EN PAPPERSMASKIN
FR7632912A FR2329799A1 (en) 1975-10-30 1976-10-29 CANVAS FOR PAPER MANUFACTURERS
DE19762649312 DE2649312A1 (en) 1975-10-30 1976-10-29 PAPER MAKING FABRIC, IN PARTICULAR FABRIC FOR THE WET AREA OF PAPER MACHINES
ES452907A ES452907A1 (en) 1975-10-30 1976-10-30 Papermakers
US06/109,661 US4289173A (en) 1975-10-30 1980-01-21 Papermakers fabrics
US06/290,007 US4529013A (en) 1975-10-30 1981-08-04 Papermakers fabrics

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB44800/75A GB1562284A (en) 1975-10-30 1975-10-30 Papermakers

Publications (1)

Publication Number Publication Date
GB1562284A true GB1562284A (en) 1980-03-12

Family

ID=10434805

Family Applications (1)

Application Number Title Priority Date Filing Date
GB44800/75A Expired GB1562284A (en) 1975-10-30 1975-10-30 Papermakers

Country Status (18)

Country Link
JP (1) JPS5285503A (en)
AT (1) AT349879B (en)
AU (1) AU498904B2 (en)
BE (1) BE847837A (en)
BR (1) BR7607275A (en)
CA (1) CA1059354A (en)
CH (1) CH616469A5 (en)
DE (1) DE2649312A1 (en)
ES (1) ES452907A1 (en)
FI (1) FI66040B (en)
FR (1) FR2329799A1 (en)
GB (1) GB1562284A (en)
IT (1) IT1068852B (en)
NL (1) NL183202B (en)
NO (1) NO147803B (en)
NZ (1) NZ182387A (en)
SE (1) SE7612079L (en)
ZA (1) ZA766250B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2183263A (en) * 1985-10-24 1987-06-03 Phoenix Ag Conveyor belt
EP2230352A1 (en) 2009-03-20 2010-09-22 Heimbach GmbH & Co.KG Woven fabric band for circulation in a machine

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2723156B2 (en) * 1988-11-25 1998-03-09 敷島紡績株式会社 Dryer canvas for papermaking
DE4229828C2 (en) * 1992-09-07 1996-07-04 Kufferath Andreas Gmbh Paper machine screen in the form of a composite fabric

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB810603A (en) * 1955-09-23 1959-03-18 Scapa Dryers Ltd Improvements in or relating to papermakers' dryer felts
DE1126724B (en) * 1956-07-03 1962-03-29 Scapa Dryers Ltd Drying felt for paper machines
FR1309607A (en) * 1961-12-29 1962-11-16 Wire mesh for sieves, more particularly for sieves of papermaking machines
SE324101B (en) * 1967-01-31 1970-05-19 Nordiska Maskinfilt Ab
GB1207446A (en) * 1967-02-06 1970-09-30 Albany Felt Co Dryer felt for paper making machines
DE1985196U (en) * 1967-12-16 1968-05-09 Heimbach Gmbh Thomas Josef SIEVE BELT.
US3603354A (en) * 1968-04-10 1971-09-07 Huyck Corp Apparatus for use on papermaking machines
DE2502466C3 (en) * 1975-01-22 1985-05-30 Hermann Wangner Gmbh & Co Kg, 7410 Reutlingen Interchangeable weft paper machine screen
JPS51116210A (en) * 1975-04-02 1976-10-13 Nippon Filcon Kk Fabric for paper screen

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2183263A (en) * 1985-10-24 1987-06-03 Phoenix Ag Conveyor belt
GB2183263B (en) * 1985-10-24 1989-11-01 Phoenix Ag Conveyor belt
EP2230352A1 (en) 2009-03-20 2010-09-22 Heimbach GmbH & Co.KG Woven fabric band for circulation in a machine
RU2447217C2 (en) * 2009-03-20 2012-04-10 Хаймбах Гмбх Унд Ко. Кг Webbing for circulation in machine
US8181673B2 (en) 2009-03-20 2012-05-22 Heimbach Gmbh & Co. Kg Woven fabric band for circulation in a machine
KR101184308B1 (en) 2009-03-20 2012-09-21 하임바흐 게엠베하 운트 콤파니 카게 Woven fabric band for circulation in a machine

Also Published As

Publication number Publication date
FR2329799B1 (en) 1982-02-12
NO147803B (en) 1983-03-07
SE7612079L (en) 1977-05-01
DE2649312A1 (en) 1977-05-05
IT1068852B (en) 1985-03-21
JPS5285503A (en) 1977-07-15
NZ182387A (en) 1979-08-31
AT349879B (en) 1979-04-25
AU498904B2 (en) 1979-03-29
CA1059354A (en) 1979-07-31
ZA766250B (en) 1977-07-27
ES452907A1 (en) 1977-10-16
BE847837A (en) 1977-02-14
FI763099A (en) 1977-05-01
NL7611946A (en) 1977-05-03
ATA804876A (en) 1978-09-15
BR7607275A (en) 1977-09-13
CH616469A5 (en) 1980-03-31
AU1901476A (en) 1978-05-04
NL183202B (en) 1988-03-16
FI66040B (en) 1984-04-30
FR2329799A1 (en) 1977-05-27
NO763679L (en) 1977-05-03

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PE20 Patent expired after termination of 20 years

Effective date: 19961028