Classifications

• • 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
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D25/00—Woven fabrics not otherwise provided for
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T442/00—Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
  • Y10T442/30—Woven fabric [i.e., woven strand or strip material]
  • Y10T442/3049—Including strand precoated with other than free metal or alloy
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T442/00—Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
  • Y10T442/30—Woven fabric [i.e., woven strand or strip material]
  • Y10T442/3179—Woven fabric is characterized by a particular or differential weave other than fabric in which the strand denier or warp/weft pick count is specified
  • Y10T442/322—Warp differs from weft
  • Y10T442/3228—Materials differ
  • Y10T442/3236—Including inorganic strand material
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T442/00—Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
  • Y10T442/30—Woven fabric [i.e., woven strand or strip material]
  • Y10T442/3179—Woven fabric is characterized by a particular or differential weave other than fabric in which the strand denier or warp/weft pick count is specified
  • Y10T442/322—Warp differs from weft
  • Y10T442/3228—Materials differ
  • Y10T442/326—Including synthetic polymeric strand material
  • Y10T442/3276—Including polyamide strand material

Definitions

• upper and lower dryer felts or fabrics are used and perform the function of pressing the web of paper against the outer periphery of the dryer rolls in intimate contact as the web travels seriatum from roll to roll and between arrays of rolls through the dryer section.
• these dryer felts or fabrics are exposed to extreme ly severe conditions of high heat, high moisture concentrations, and (frequently) chemically active environments.
• dryer felt is a misnomer since, as noted in the publication Modern Pulp and Papermaking (by John P. Calkin, Reinhold Publishing Co. 1957, at Page 349), The dryer felt is actually not a felt, but a heavy duck made essentially of cotton. By papermakers usage it is termed a felt'.” Historically, such felts have been made from cotton, or cotton and asbestos, although in some cases, material such as wool has also been used. More recently, dryer fabrics" have come into widespread use in the dryer sections of papermaking machines.
• Dryer fabrics are usually made from synthetic materials, such as polyesters and/or polyamides, in the form of monofilaments or multifilaments that are woven into open-weave structures. Although in the ambient conditions normally encountered in dryer sections of papermaking machines such dryer fabrics exhibit a significiantly longer life than did the previously used dryer felts, there are, nevertheless, continuing efforts to increase the useful life of such dryer fabrics even beyond that previously achieved.
• Yet another object of this invention is to provide a dryer fabric less susceptible to degradation than prior art structures.
• Another object is to provide a dryer fabric with improved heat, moisture, and/or chemical stability.
• Yam means any continuous structure useful as a constituent member in the weaving of fabrics, whether a monofilament, a multifilament, a plurality of multifilaments bundled together, or a plurality of spun staple fibers.
• Filament means a single thread, or a thin flexible threadlike object.
• Crinkled means having many short bends or turns.
• Bulky (as applied to yarns) means having a relatively large percentage of its cross-sectional area unoccupied by constituent filament material, wlhereby impregnation of the yarn by treating resins and consequent substantial entire encapsulation of the constituent filament material may be facilitated.
• Textured (asapplied to yarns) :means having rendered bulky a yarn comprising a plurality of filaments made from man-made materials which are not originally or inherently crinkled by causing said filaments to become crinkled; said plurality of filaments being, or being comprised of, a group of more than one substantially continuous filaments or a plurality of such groups of filaments (such yarns are also sometimes referred to in the textile arts as ftexturedyarns).
• Machine direction means the normal direction of travel of the dryer fabric when it is inuse on the papermaking machine.
• Cross-machine direction means a direction substantially normal to the machine direction.
• fiberglass may be incorporated into a papermakers dryer fabric and rendered suitable for the intended use by using, and subsequently resin impregnating, fiberglass yarns which have been rendered bulky (as defined above) by any of a variety of methods, including texturizing (methods for achieving which are disclosed in Cobb et al., U.S. Pat. No. 3,262,177 and the publication Textile World for December, 1969, (Vol.1 19, No. 12) at Pages 60 through 63).
• EXAMPLE A papermakers dryer fabric was made 162 feet long by 165 inches in width. For warp yarns it had 36 ends per inch of 1,200 denier, 600 filament NOMEX, high temperature polyamide yarns, as manufactured by E.I. duPont de Nemours & Co. For filling yarns, it had Owens-Corning textured fiberglass type No. 401, DE75 /3 (which is a code to indicate'that the yarns consisted of filaments comprising 7,500 yards per pound, 5 ends of which were plied, and 3 such plies being themselves plied together).
• the fabric was also rendered less susceptible to machine direction stretch with attendant cross-machine direction narrowing through crimp interchange.
• the fabric was treated with a resin according to a known technique substantially in accordance with Wagner U.S. Pat. No. 3,192,599, such that the fabric .was rendered sufficiently limber to permit it to be used in the papermaking process, while keeping the constituent members of the fiberglass yarns from abrading each other.
• a machine direction tensile strength 402 lbs. per lineal inch and a cross machine tensile strength of 254 lbs. per lineal inch.
• the fabric was operated on the papermaking machine for 8 months, at which time it was removed, but not for reason of any failure of the fabric, and inspection after removal indicated it would have operated for several more months.
• This 8-month period was the longest that any conventional dryer fabric had operated up to that time on this papermachine position.
• the fabric was removed, it was subjected to various measurements an and found to have a length of 159 feet, a width of 164 /2 inches, a machine-direction tensile strength of 257.89 lbs. per inch, and a cross-machine direction tensile strength of 284 lbs/in.
• this fabric was more highly resistant to the derogatory effects of high heat, high tension, and the chemical environment to which it was exposed throughout its useful life on the papermaking machine than were any of the conventional clothing previously used on this papermachine position.
• a woven dryer fabric for use in a papermaking machine comprising bulky, resin impregnated yarns in the crossmachine direction, said yarns, prior to impregnation, comprising fibers which have poor resistance to mutual abrasion.
• the dryer fabric described in claim 2 comprising machine direction yarns made from manmade material characterized by being substantially stable, physically and chemically over a long period of time to the ambient conditions to which the fabric is exposed when in use.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Paper (AREA)

Applications Claiming Priority (1)

Publications (1)

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Family Applications (1)

Country Status (7)

Cited By (9)

Families Citing this family (3)

Citations (2)

• 1970
  • 1970-02-11 US US10627A patent/US3653961A/en not_active Expired - Lifetime
• 1971
  • 1971-02-02 BR BR794/71A patent/BR7100794D0/pt unknown
  • 1971-02-02 DE DE19712104832 patent/DE2104832A1/de active Pending
  • 1971-02-08 NL NL7101651A patent/NL7101651A/xx unknown
  • 1971-02-08 AU AU25160/71A patent/AU2516071A/en not_active Expired
  • 1971-02-10 FR FR7104453A patent/FR2079359B3/fr not_active Expired
  • 1971-02-11 CA CA105,152A patent/CA945455A/en not_active Expired

Patent Citations (2)

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