WO2000019014A1 - Papier de forte epaisseur et toile de machine a papier servant a la production de ce papier - Google Patents

Papier de forte epaisseur et toile de machine a papier servant a la production de ce papier Download PDF

Info

Publication number
WO2000019014A1
WO2000019014A1 PCT/US1999/021877 US9921877W WO0019014A1 WO 2000019014 A1 WO2000019014 A1 WO 2000019014A1 US 9921877 W US9921877 W US 9921877W WO 0019014 A1 WO0019014 A1 WO 0019014A1
Authority
WO
WIPO (PCT)
Prior art keywords
web
belt
deflection
papermaking
papermaking belt
Prior art date
Application number
PCT/US1999/021877
Other languages
English (en)
Inventor
Jonathan Andrew Ficke
Yanping Zhang
Kenneth Douglas Vinson
Original Assignee
The Procter & Gamble Company
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 The Procter & Gamble Company filed Critical The Procter & Gamble Company
Priority to AT99969755T priority Critical patent/ATE256783T1/de
Priority to AU60554/99A priority patent/AU745387B2/en
Priority to CA002344538A priority patent/CA2344538C/fr
Priority to EP99969755A priority patent/EP1153170B1/fr
Priority to BR9914223-6A priority patent/BR9914223A/pt
Priority to JP2000572452A priority patent/JP4405677B2/ja
Priority to DE69913741T priority patent/DE69913741T2/de
Priority to KR1020017003910A priority patent/KR20010075403A/ko
Priority to NZ510468A priority patent/NZ510468A/en
Publication of WO2000019014A1 publication Critical patent/WO2000019014A1/fr

Links

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F11/00—Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines
    • D21F11/006—Making patterned paper

Definitions

  • the present invention is related to papermaking belts useful in papermaking machines for making low density, soft, absorbent paper products and the paper products produced thereby. More particularly, this invention is concerned with papermaking belts comprising a patterned framework and a reinforcing structure and the high caliper/low density paper products produced thereby.
  • Cellulosic fibrous webs such as paper are well known in the art. Such fibrous webs are in common use today for paper towels, toilet tissue, facial tissue, napkins and the like. The large demand for such paper products has created a demand for improved versions of the products and the methods of their manufacture.
  • cellulosic fibrous webs In order to meet the needs of the consumer, cellulosic fibrous webs must exhibit several characteristics. They must have sufficient tensile strength to prevent the structures from tearing or shredding during ordinary use or when relatively small tensile forces are applied. The cellulosic fibrous webs must be absorbent, so that liquids may be quickly absorbed and fully retained by the fibrous structure.
  • Tensile strength is the ability of the cellulosic fibrous web to retain its physical integrity during use. Tensile strength is a function of the basis weight of the cellulosic fibrous web.
  • Absorbency is the property of the cellulosic fibrous web which allows it to attract and retain contacted fluids. Absorbency is influenced by the density of the cellulosic fibrous web. If the web is too dense, the interstices between fibers may be too small and the rate of absorption may not be great enough for the intended use. If the interstices are too large, capillary attraction of contacted fluids is minimized preventing fluids from being retained by the cellulosic fibrous web due to surface tension limitations.
  • the web should exhibit softness, so that it is tactilely pleasant and not harsh during use.
  • Softness is the ability of the cellulosic fibrous web to impart a particularly desirable tactile sensation to the user's skin.
  • Softness is universally proportional to the ability of the cellulosic fibrous web to resist deformation in a direction normal to the plane of the cellulosic fibrous web.
  • Caliper is the apparent thickness of a cellulosic fibrous web measured under a certain mechanical pressure and is a function of basis weight and web structure. Strength, absorbency, and softness are influenced by the caliper of the cellulosic fibrous web.
  • Processes for the manufacturing of paper products generally involve the preparation of an aqueous slurry of cellulosic fibers and subsequent removal of water from the slurry while contemporaneously rearranging the fibers to form an embryonic web.
  • Various types of machinery can be employed to assist in the dewatering process.
  • a typical manufacturing process employs a Fourdrinier wire papermaking machine where the paper slurry is fed onto a surface of a traveling endless belt where the initial dewatering and rearranging of fibers is carried out.
  • the paper web is carried through a drying process on another fabric referred to as the drying fabric which is in the form of an endless belt.
  • the drying process can involve mechanical compaction of the paper web, vacuum dewatering, through air drying, and other types of processes.
  • the embryonic web takes on a specific pattern or shape caused by the arrangement and deflection of cellulosic fibers.
  • U.S. Patent No. 4,529,480 issued to Trokhan on July 16, 1985 introduced a papermaking belt comprising a foraminous woven member which was surrounded by hardened photosensitive resin framework.
  • the resin framework was provided with a plurality of discrete, isolated channels known as deflection conduits.
  • the papermaking belt used in the process was termed a deflection member because the papermaking fibers deflected into conduits and became rearranged therein upon the application of a fluid pressure differential.
  • the utilization of the belt in the papermaking process provided the possibility of creating paper having certain desired characteristics of strength, absorption, and softness.
  • the paper produced using the process disclosed in U.S. Patent No. 4,529,480 is described in U.S. Patent No. 4,637,859 issued to Trokhan which is incorporated herein by reference.
  • the paper is characterized by having two physically distinct regions distributed across its surfaces.
  • One region is a continuous network region which has a relatively high density and high intrinsic strength.
  • the other region is one which is comprised of a plurality of domes which are completely encircled by the network region.
  • the domes in the latter region have relatively low densities and relatively low intrinsic strength compared to the network region.
  • the domes are produced as fibers fill the deflection conduits of the papermaking belt during the papermaking process.
  • the deflection conduits prevent the fibers depositing therein from being compacted as the paper web is compressed during the drying process.
  • the domes are thicker having a lower density and intrinsic strength compared to the compacted regions of the web. Consequently, the caliper of the paper web is limited by the intrinsic strength of the domes.
  • the fibers are predominantly oriented in the X-Y plane of the web providing negligible Z-direction structural rigidity.
  • the fibers oriented in the X-Y plane are compacted by mechanical pressure, the fibers are pressed together increasing the density of the paper web while decreasing the thickness.
  • Orienting fibers in the Z direction of the web enhances the web's Z-direction structural rigidity and its corresponding resistance to mechanical pressure. Accordingly, maximizing fiber orientation in the Z-direction maximizes caliper.
  • Deflection conduits provide a means for producing a Z-direction fiber orientation by enabling the fibers to deflect along the periphery of the deflection conduits.
  • the total fiber deflection is dependent on the size and shape of the deflection conduits relative to the fiber length.
  • conduits also influences fiber deflection.
  • deflection conduits defined by a periphery forming sharp corners or small radii increase the potential for fiber bridging which minimizes fiber deflection. See US Patent No. 5,679,222 issued to Rasch et al. October 21, 1997 for examples of various conduit shapes that can effect fiber bridging.
  • the present invention provides a papermaking belt comprising a continuous network region and a plurality of discrete deflection conduits which are sized and shaped to optimize fiber deflection and corresponding Z-direction fiber orientation.
  • the invention further provides a paper web comprising an essentially continuous, essentially macroscopically monoplanar network region and a plurality of discrete domes dispersed therethroughout. The domes are sized and shaped to yield optimum caliper.
  • the present invention is directed to a papermaking belt having a patterned framework capable of producing a low density/high caliper paper web and the paper web produced thereby.
  • the papermaking belt comprises a reinforcing structure having a patterned framework disposed thereon.
  • the patterned framework includes a continuous network region and a plurality of discrete deflection conduits, wherein the deflection conduits are isolated from one another by the continuous network region.
  • the deflection conduits are generally elliptical in shape and sized relative to a mean web fiber length, L , such that the mean width, W , of the conduits is L ⁇ W ⁇ 3 L .
  • the deflection conduits have an aspect ratio ranging from at least about 1.0 to about 2.0 and a minimum radius of curvature wherein the ratio of minimum radius of curvature to mean width ranges from at least about 0.29 to about 0.50.
  • the deflection conduits may be arranged in a hexagonal pattern in order to maximize the concentration of conduits per unit area while at the same time minimizing the area of the continuous network region.
  • the continuous network region provides a knuckle area having a width ranging from at least about 0.007 inches to about 0.020 inches.
  • the paper produced on such papermaking belt comprises an essentially macroscopically monoplanar network region and a plurality of discrete domes dispersed throughout and isolated from one another by the continuous network region.
  • the domes take on the shape and arrangement of the generally elliptical deflection conduits previously described.
  • FIG. 1 is a schematic side elevational view of one embodiment of a papermaking machine which uses the papermaking belt of the present invention.
  • FIG. 2 is a top plan view of a portion of the papermaking belt of the present invention, showing the framework joined to the reinforcing structure and having elliptically-shaped paper-side openings of the deflection conduits.
  • FIG. 3 is a vertical cross-sectional view of a portion of the papermaking belt shown in FIG. 2 as taken along line 3-3.
  • FIG. 4 is a vertical cross-sectional view of a portion of the papermaking belt shown in FIG. 3 depicting fibers bridging the deflection conduit.
  • FIG. 5 is a vertical cross-sectional view of a portion of the papermaking belt shown in FIG. 3 depicting fibers collecting in the bottom of the deflection conduit.
  • FIG. 6 is a vertical cross-sectional view of a portion of the papermaking belt shown in FIG. 3 depicting a fiber cantilevered over the deflection conduit opening to illustrate fiber defection.
  • FIG. 7 is a vertical cross-sectional view of a portion of the papermaking belt shown in FIG. 3 depicting a fiber bridging the deflection conduit opening to illustrate fiber defection.
  • FIG. 8a & 8b are a top plan views of conduit shapes having tight radii or sharp corners making them prone to fiber bridging.
  • FIG. 9 is a schematic representation of an elliptically shaped conduit having a rectilinear periphery.
  • FIG. 10 is a schematic representation of an elliptically shaped conduit having a curvilinear periphery.
  • FIG. 1 1 is a top plan schematic representation of deflection conduits arranged in a hexagonal pattern with major axes oriented parallel to the machine direction of the belt.
  • FIG. 12 is a top plan schematic representation of deflection conduits arranged in a hexagonal pattern with major axes oriented diagonal to the machine direction of the belt.
  • FIG. 13 is a vertical cross-sectional view of a portion of the papermaking belt shown in FIG. 3 depicting fibers deflecting into the deflection conduit and illustrating the relation between the conduit width, the conduit Z-direction height , and the web stretch.
  • Figure 14 is a vertical cross-sectional view of a portion of the papermaking belt shown in FIG. 3 depicting fibers deflecting into the deflection conduit and illustrating the relation between the web deflection angle and the angle forming the knuckle/conduit opening interface.
  • Figure 15 is a top plan schematic representation of a paper web having domes arranged in a hexagonal pattern.
  • Figure 16 is a vertical cross-sectional view of a portion of the paper web shown in FIG. 15 as taken along line 16-- 16.
  • Machine direction is the direction parallel to the flow of the paper web through the papermaking equipment.
  • Cross machine direction is the direction perpendicular to the machine direction in the X-Y plane.
  • Center of area is a point within the deflection conduit that would coincide with the center of mass of a thin uniform distribution of matter bounded by the periphery of the deflection conduit.
  • Major axis is the longest axis crossing the center of area of the conduit and joining two points along the perimeter of the conduit.
  • Minor axis is the shortest axis or width crossing the center of area of the conduit and joining two points along the perimeter of the conduit.
  • Aspect Ratio is the ratio of the major axis length to the minor axis length.
  • the mean width of the conduit is the average length of straight lines drawn through the center of area of the conduit and joining two points on the perimeter thereof.
  • Radius of curvature is the instantaneous radius of curvature at a point on a curve. Curvilinear pertains to curved lines.
  • Rectilinear pertains to straight lines.
  • Z-direction height is the portion of the resin framework extending from the paper facing side of the reinforcing structure.
  • Mean fiber length is the length weighted average fiber length.
  • the specification contains a detailed description of (1) the papermaking belt of the present invention and (2) the finished paper product of the present invention.
  • the papermaking belt of the present invention takes the form of an endless belt, papermaking belt 10.
  • the papermaking belt 10 has a paper-contacting side 1 1 and a backside 12 opposite the paper-contacting side 1 1.
  • the papermaking belt 10 carries a paper web (or "fiber web") in various stages of its formation (an embryonic web 27 and an intermediate web 29). Processes of forming embryonic webs are described in many references, such as U.S. Pat. No. 3,301 ,746, issued to Sanford and Sisson on Jan. 31 , 1974, and U.S. Pat. No. 3,994,771 , issued to Morgan and Rich on Nov. 30, 1976, both incorporated herein by reference.
  • the papermaking belt 10 travels in the direction indicated by directional arrow B around the return rolls 19a and 19b, impression nip roll 20, return rolls 19c, 19d, 19e, 19f, and emulsion distributing roll 21.
  • the loop around which the papermaking belt 10 travels includes a means for applying a fluid pressure differential to the embryonic web 27. such as vacuum pickup shoe (PUS) 24a and multi-slot vacuum box 24.
  • PUS vacuum pickup shoe
  • the papermaking belt 10 also travels around a predryer such as blow-through dryer 26, and passes between a nip formed by the impression nip roll 20 and a Yankee drying drum 28.
  • the preferred embodiment of the papermaking belt of the present invention is in the form of an endless belt 10, it can be incorporated into numerous other forms which include, for instance, stationary plates for use in making handsheets or rotating drums for use with other types of continuous process. Regardless of the physical form which the papermaking belt 10 takes for the execution of the claimed invention, it generally has certain physical characteristics set forth below.
  • the papermaking belt 10 of the present invention may be made according to commonly assigned U.S. Pat. No. 5,334,289, issued in the name of Trokhan et al., which patent is incorporated by reference herein.
  • the belt 10 comprises two primary components: a framework 30 and a reinforcing structure 32.
  • the framework 30 preferably comprises a cured polymeric photosensitive resin.
  • the framework 30 and belt 10 have a first surface 1 1 which defines the paper contacting side 1 1 of the belt 10 and an opposed second surface 12 oriented towards the papermaking machine on which the belt 10 is used.
  • X, Y and Z directions are orientations relating to the papermaking belt 10 of the present invention (or paper web 27 disposed on the belt) in a Cartesian coordinate system.
  • the papermaking belt 10 according to the present invention is macroscopically monoplanar.
  • the plane of the papermaking belt 10 defines its X-Y directions. Perpendicular to the X-Y directions and the plane of the papermaking belt 10 is the Z-direction of the belt 10.
  • the web 27 according to the present invention can be thought of as macroscopically monoplanar and lying in an X-Y plane.
  • Perpendicular to the X-Y directions and the plane of the web 27 is the Z-direction of the web 27.
  • the framework 30 defines a predetermined pattern and provides a knuckle area 36 which imprints a like pattern onto the web 27 of the present invention.
  • a particularly preferred pattern for the framework 30 is an essentially continuous network. If the preferred essentially continuous network pattern is selected for the framework 30, discrete deflection conduits 34 will extend between the first surface 1 1 and the second surface 12 of the belt 10. The essentially continuous network surrounds and defines the deflection conduits 34.
  • the framework 30 prints a pattern corresponding to that of the framework 30 onto the web 27 carried thereon. Imprinting occurs anytime the belt 10 and web 27 pass between two rigid surfaces having a clearance sufficient to cause imprinting.
  • the second surface 12 of the belt 10 is the machine contacting surface of the belt 10.
  • the second surface may be made with a backside network having passageways therein which are distinct from the deflection conduits 34.
  • the passageways provide irregularities in the texture of the backside of the second surface of the belt 10.
  • the passageways allow for air leakage in the X-Y plane of the belt 10, which leakage does not necessarily flow in the Z-direction through the deflection conduits 34 of the belt 10.
  • Belts 10 inco ⁇ orating such backside texturing may be made according to any of commonly assigned U.S.
  • Patents 5,098,522 issued March 24, 1992 to Smurkoski et al.; 5,364,504 issued November 15, 1994 to Smurkoski et al.; and 5,260,171 issued November 9, 1993 to Smurkoski et al., the disclosures of which are inco ⁇ orated by reference.
  • the second primary component of the belt 10 according to the present invention is the reinforcing structure 32.
  • the reinforcing structure 32 like the framework 30, has a first or paper facing surface 13 and a second or machine facing surface 12 opposite the paper facing surface.
  • the reinforcing structure 32 is primarily disposed between the opposed surfaces of the belt 10 and may have a surface coincident the backside of the belt 10.
  • the reinforcing structure 32 provides support for the framework 30.
  • the reinforcing component is typically woven, as is well known in the art.
  • the portions of the reinforcing structure 32 registered with the deflection conduits 34 prevent fibers used in papermaking from passing completely through the deflection conduits 34 and thereby reduces the occurrences of pinholes. If one does not wish to use a woven fabric for the reinforcing structure 32, a nonwoven element, screen, net, or a plate having a plurality of holes therethrough may provide adequate strength and support for the framework 30 of the present invention.
  • the framework 30 is joined to the reinforcing structure 32.
  • the framework 30 extends outwardly from the paper- facing side 13 of the reinforcing structure 32.
  • the reinforcing structure 32 strengthens the resin framework 30 and has suitable projected open area to allow the vacuum dewatering machinery employed in the papermaking process to perform adequately its function of removing water from the embryonic web 27, and to permit water removed from the embryonic web 27 to pass through the papermaking belt 10.
  • the belt 10 according to the present invention may be made according to any of commonly assigned U.S. Patents: 4,514,345, issued April 30, 1985 to Johnson et al.; 4,528,239, issued July 9, 1985 to Trokhan; 5,098,522, issued March 24, 1992; 5,260,171, issued Nov. 9, 1993 to Smurkoski et al.; 5,275,700, issued Jan. 4, 1994 to Trokhan; 5,328,565, issued July 12, 1994 to Rasch et al.; 5,334,289, issued Aug. 2, 1994 to Trokhan et al.; 5,431 ,786, issued July 1 1, 1995 to Rasch et al.; 5,496,624, issued March 5,
  • the ability to produce a paper web having a particular thickness is a function of the caliper of the web.
  • Caliper is the apparent thickness of a cellulosic fibrous web measured under a certain mechanical pressure.
  • Caliper is a function of web basis weight and web structure. Basis weight is the weight in pounds of 3000 square feet of paper.
  • Web structure pertains to orientation and density of fibers making up the web 27. Fibers making up the web 27 are typically oriented in the X-Y plane and provide minimal structural support in the Z-direction.
  • the web 27 is compressed by the patterned framework 30, the web 27 is compacted creating a patterned, high density region that is reduced in thickness. Conversely, portions of the web 27 covering the deflection conduits 34 are not compacted and as a result, thicker, low density regions are produced.
  • the low density regions give the web 27 an apparent thickness. Since the fibers making up a typical dome are predominently oriented in the X- Y plane of the web 27, the fibers provide negligible Z-direction support. Consequently, the domes are highly susceptible to being deformed and reduced in thickness during subsequent papermaking operations. Thus, the caliper of the web 27 is generally limited by the domes' ability to withstand mechanical pressure.
  • deflection conduits 34 provide a means for deflecting fibers in the Z- direction along the periphery 38. Fiber deflection produces a fiber orientation which includes a Z-direction component.
  • deflection conduits 34 are sized and shaped to maximize fiber deflection along the peripheries 38.
  • Water removal from the embryonic web 27 begins as the fibers 50 are deflected into the deflection conduits 34.
  • the water removal results in a decrease in fiber mobility which tends to fix the fibers in place after they have been deflected and rearranged.
  • Deflection of the fibers into the deflection conduits 34 can be induced by, the application of differential fluid pressure to the embryonic web 27.
  • One preferred method of applying differential pressure is by exposing the embryonic web 27 to a vacuum through deflection conduits 34.
  • FIG. 1 the preferred method is illustrated by the use of pick-up shoe 24.
  • the rearrangement of the fibers in the embryonic web 27 relative to the deflection conduits 34 can generally take one of two models, dependent on a number of factors including fiber length. As schematically shown in FIG. 4, the ends of longer fibers 50 can be restrained on the top of the knuckles 36 allowing the middle parts of fibers 50 to be bent into the conduit 34 without being fully deflected.
  • Fiber deflection is function of the web's resistance to bending. The higher the web bending stiffness the greater the resistance to deflection. The bending stiffness of a web is dominated by two factors: (1 ) the bending stiffness of individual fibers; and (2) fiber-to-fiber bonding strength.
  • f B F L 3 /8EI (1) where, f B - deflection at point B;
  • the fiber segment 50 is longer than conduit width, resulting in two fixed points A and B. If the fiber segment 50 experiences the same vacuum, the supporting forces at A and B create offsetting bending moments resulting in a fiber deflection at point C defined by
  • fiber deflection can be enhanced by sizing the deflection conduits 34 to minimize the occurrences of fiber bridging.
  • the size of the conduit is also limited by the number of small fibers in the furnish capable of accumulating in the conduits 34 and consequently, inhibiting the larger fibers from deflecting therein.
  • Furnish normally includes both hardwood and softwood.
  • An example of hardwood fiber is Eucalyptus (EUC) while an example of softwood fiber is Northern Softwood Kraft (NSK).
  • An example of a furnish comprises 30% by weight softwood and 70% by weight hardwood.
  • the conduit width, W be sized relative to the mean fiber length of the furnish, L , where
  • the mean fiber length is the length weighted average fiber length determined by
  • I, Average lengths of fibers in class .
  • n l Number of fibers measured in class / ' .
  • the length weighted average fiber length for the present invention is about 0.043 inches.
  • the conduits 34 may take on a variety of different shapes having either variable or constant widths. Conduit shapes having variable widths are defined in terms of the major axis 40, the minor axis 42, and the mean width 46. As defined, the major axis 40 is the longest axis or width crossing the center of area of the conduit, the minor axis 42 is the shortest width crossing the center of area of the conduit, and the mean width 46 is the average width crossing center of area of the conduit.
  • the mean width 46 is determined by first measuring the length of a line drawn through the center of area in the CD joining two points on the perimeter of the conduit. The lengths of similar lines oriented at A ⁇ angular increments with respect to the CD (such as 15 degrees or less ranging from 0° to 165° where 0° represents the CD) are measured and averaged to determine the mean width.
  • the preferred min conduit width is at least about 0.043 inches.
  • the conduits such that the mean conduit width ranges from about 0.043 inches to about 0.129 inches.
  • the web 27 is approximately a two-dimensional fiber network.
  • An ideal fiber network comprises a random distribution of fibers where the fiber orientation does not favor a particular direction.
  • the mean fiber length, L is same in all directions.
  • fiber networks are typically arranged in the web having a fiber orientation that is biased in a particular direction.
  • the mean fiber length will vary relative to angular orientation in the X-Y plane of the web 27. Theoretically, such mean fiber length is designated, L ⁇ , where
  • L ⁇ Component Lengths of fibers at angular orientation, ⁇ , in X-Y plane.
  • L ⁇ Mean fiber length at angular orientation, ⁇ , in X-Y plane.
  • n Number of fibers measured at angular orientation, ⁇ , in X-Y plane.
  • the fibers 50 making up the two dimensional fiber network are predominantly oriented in the machine direction MD. Consequently, the mean fiber length in the machine direction is greater than the mean fiber length in the cross machine direction CD.
  • the conduits 34 it is preferred to orient the conduits 34 such that the major axes 40 run parallel to the machine direction of the belt.
  • the major axis 40 may also be oriented at a diagonal, where, as illustrated in Figure 12, diagonal is defined as an angle 54 oriented 22.5° ⁇ 22.5° relative to MD.
  • the shape of the conduit is defined in terms of an aspect ratio, R A , which is defined as the ratio of the major axis 40 to the minor axis 42.
  • R A the aspect ratio
  • the physical properties of a paper web 27 are largely influenced by the orientation of fibers in the X-Y plane of the web 27.
  • a web 27 having a fiber orientation which favors MD has a higher tensile strength in MD than in CD, a higher stretch in CD than in MD, and a higher bending stiffness in MD than in CD.
  • the web tensile strength is proportional to the corresponding lengths of fibers oriented in a particular direction in the X-Y plane. Therefore, the web tensile strength in the MD and CD is proportional to the mean fiber lengths in the MD and CD.
  • the tensile strengths of the web 27 in MD and CD were measured using a Thwing-Albert Intelect II Standard Tensile Tester manufactured by Thwing-Albert
  • the preferred conduit shape providing optimum fiber deflection and corresponding caliper generation has an aspect ratio ranging from 1 to about 2.
  • a more preferred shape has an aspect ratio ranging from about 1.3 to 1.7.
  • a most preferred shape has an aspect ratio ranging from 1.4 to 1.6.
  • the shape of the deflection conduit 34 is not only significant for minimizing fiber bridging across the width of the conduit but also for minimizing fiber bridging along the perimeter 38 of the conduit walls. Conduit walls forming tight radii or sha ⁇ corners provide additional locations for fiber bridging. Examples of unfavorable conduit shapes for this pu ⁇ ose are shown in Figures 8a & 8b.
  • a preferred conduit shape for the present invention is one that is generally elliptical which includes, but is not limited to, circles, ovals, and polygons of six or more sides.
  • Figure 9 illustrates an elliptically shaped conduit having a rectilinear periphery comprising individual wall segments 44.
  • fiber bridging along the periphery is minimized by providing an included angle 39 between adjacent wall segments which is at least about 120 degrees.
  • Figure 10 illustrates an elliptically shaped conduit having a curvilinear periphery concave toward the center of the conduit.
  • the curvilinear periphery includes a minimum radius of curvature 48.
  • fiber bridging along the periphery is minimized by limiting the shape such that the ratio of the minimum radius of curvature 48 to the mean conduit width is at least 0.29 and no more than 0.50.
  • OB is the Z-direction height
  • W is the conduit width
  • Critical stretch determines when the web 27 will break. If the stretch is greater than the critical stretch in the web 27, the network will be broken causing pinholes in the web.
  • the critical stretch in the web 27 depends on the network properties such as fiber length and fiber orientation. The fiber-to-fiber bonding does not play a role in critical stretch because the web at the pick up shoe is wet and the fiber-to-fiber bonds are not well established.
  • the critical stretch ⁇ crilical is a complicated function of fiber length, fiber orientation and basis weight. Qualitatively, the critical stretch increases when fiber length and/or basis weight increases.
  • the preferred Z-direction height 60 for maximum web deflection ranges from at least about 0.005 inches to about 0.039 inches.
  • the total deflection a web will undergo in the deflection conduits is also largely determined by the angle forming the knuckle/conduit interface of the patterned framework.
  • the web deflection angle 62 is defined as the angle of the web at the knuckle/conduit interface with respect to the Z-direction.
  • An illustration of the web deflection is shown in Figure 14.
  • Fibers 50 accumulating at the knuckle/conduit interface are oriented with a Z-direction component which enables them to provide the support structure capable of withstanding external compressive forces. Fibers oriented parallel to the Z-direction at the knuckle/conduit interface provide maximum support.
  • the walls of the deflection conduits are sloped forming a resin angle 64 at the knuckle/conduit interface.
  • the resin angle 64 further limits the web deflection since the deflection angle 62 cannot be less than the resin angle 64.
  • the resin angle is preferably sloped between 5 degrees and 10 degrees.
  • the web deflection angle typically ranges from about 20 degrees to about 50 degrees.
  • the number of fibers 50 in the transition interface can be optimized by maximizing the total perimeter 38 of the interface. This is equivalent to maximizing the number of deflection conduits 34 per unit area or to minimizing the percentage of knuckle area 36.
  • conduits 34 can be packed to an extreme. However, as shown in Figures 1 1 and 12 the knuckles 36 separating conduits 34 are required to have a minimum width 52 in order to enable the resin to securely attach to the secondary 32.
  • the preferred minimum knuckle width 52 ranges from at least about 0.007 inches to about 0.020 inches.
  • conduits 34 can be maximized by packing conduits 34 into more efficient arrangements.
  • a preferred arrangement of conduits 34 is one forming a hexagonal pattern as shown in Figures 1 1 and 12.
  • the paper 80 of the present invention has two primary regions.
  • the first region comprises an imprinted region 82 which is imprinted against the framework 30 of the belt 1 .
  • the imprinted region 82 preferably comprises an essentially continuous network.
  • the continuous network 82 of the first region of the paper 80 js made on the essentially continuous framework 30 of the belt 10 and will generally correspond thereto in geometry and be disposed very closely thereto in position during papermaking.
  • the second region of the paper 80 comprises a plurality of domes 84 dispersed throughout the imprinted network region 82.
  • the domes 84 generally correspond in geometry, and during papermaking, in position to the deflection conduits 34 in the belt 10. By conforming to the deflection conduits 34 during the papermaking process, the fibers in the domes 84 are deflected in the Z-direction between the paper facing surface of the framework 30 and the paper facing surface of the reinforcing structure 32. As a result, the domes 84 protrude outwardly from the essentially continuous network region 82 of the paper 80.
  • the domes 84 are preferably discrete, isolated one from another by the continuous network region 82.
  • the domes 84 and essentially continuous network regions 82 of the paper 80 may have generally equivalent basis weights.
  • the density of the domes 84 is decreased relative to the density of the essentially continuous network region 82.
  • the essentially continuous network region 82 (or other pattern as may be selected) may later be imprinted as, for example, against a Yankee drying drum. Such imprinting increases the density of the essentially continuous network region 82 relative to that of the domes 84.
  • the resulting paper 80 may be later embossed as is well known in the art.
  • the paper 80 according to the present invention may be made according to any of commonly assigned U.S. Patents: 4,529,480, issued July 16, 1985 to Trokhan; 4,637,859, issued Jan. 20, 1987 to Trokhan; 5,364,504, issued Nov. 15, 1994 to Smurkoski et al.; and 5,529,664, issued June 25, 1996 to Trokhan et al. and 5,679,222 issued Oct. 21, 1997 to Rasch et al., the disclosures of which are inco ⁇ orated herein by reference.
  • the shapes of the domes 84 in the X-Y plane include, but are not limited to, circles, ovals, and polygons of six or more sides.
  • the domes 84 arc generally elliptical in shape comprising either curvilinear or rectilinear peripheries 86.
  • the curvilinear periphery 86 comprises a minimum radius of curvature such that the ratio of the minimum radius of curvature to mean width of the dome ranges from at least about 0.29 to about 0.50.
  • the rectilinear periphery 86 may comprise of a number of wall segments where the included angle between adjacent wall segments is at least about 120 degrees.
  • Providing a paper 80 having high caliper requires maximizing the number Z- direction fibers per unit area in the web.
  • the majority of the Z-direction fibers are oriented along the periphery 86 of the domes 84 where fiber deflection occurs.
  • Z- direction fiber orientation and corresponding caliper of the paper web is largely dependent on the number of domes per unit area.
  • the number of domes 84 per unit area is maximized by minimizing the distance between adjacent domes which is accomplished by arranging the domes into efficient patterns.
  • the preferred minimum distance 88 between domes 84 is at least about 0.007 inches and no more than 0.020 inches.
  • the preferred arrangement of the domes 84 is one forming a hexagonal pattern.
  • the number of domes 84 per unit area of the paper 80 is largely dependent on the size and shape of the deflection conduits previously described.
  • the preferred mean width of the domes 84 is at least about 0.043 inches and less than about 0.129 inches.
  • the preferred generally elliptical shape for the domes is one having an aspect ratio ranging from 1 to about 2.
  • a more preferred generally elliptical shape has an aspect ratio ranging from about 1.3 to 1.7.
  • a most preferred generally elliptical shape has an aspect ratio ranging from 1.4 to 1.6.
  • the caliper of the paper web is typically measured under a pressure of 95 grams per square inch using a round presser foot having a diameter of 2 inches, after a dwell time of 3 seconds.
  • the caliper can be measured using a Thwing-Albert Thickness Tester Model 89-100, manufactured by the Thwing-Albert Instrument Company of Philadelphia, Pennsylvania.
  • the caliper is measured under TAPPI temperature and humidity conditions.
  • the caliper was measured on a paper web comprising two plies.
  • the caliper of the two ply paper web is preferably between 20 mils and 40 mils. More preferably the caliper of the two ply paper web is between 38 mils and 46 mils. Most preferably the caliper of the two ply paper web is between 25 mils and 30 mils.

Landscapes

  • Paper (AREA)
  • Belt Conveyors (AREA)

Abstract

L'invention concerne une toile de machine à papier servant à produire un papier de forte épaisseur à base de fibres de fabrication de papier, ainsi que la feuille continue de papier ainsi produite. Cette toile comprend une structure renforçatrice présentant une région à réseau continu ainsi que plusieurs gorges distinctes de déflexion, agencées sur cette région. Ces gorges sont dimensionnées, mises en forme et conçues pour maximiser la déflexion des fibres le long de la périphérie des gorges, elles sont généralement de forme elliptique et présentent une largeur moyenne dimensionnée par rapport à la longueur moyenne des fibres. Ces gorges sont agencées pour maximiser le périmètre d'un motif, et la déflexion correspondante des fibres, par unité de surface.
PCT/US1999/021877 1998-09-30 1999-09-21 Papier de forte epaisseur et toile de machine a papier servant a la production de ce papier WO2000019014A1 (fr)

Priority Applications (9)

Application Number Priority Date Filing Date Title
AT99969755T ATE256783T1 (de) 1998-09-30 1999-09-21 Dickes papier und papiermachergewebe zu seiner herstellung
AU60554/99A AU745387B2 (en) 1998-09-30 1999-09-21 High caliper paper and papermaking belt for producing the same
CA002344538A CA2344538C (fr) 1998-09-30 1999-09-21 Papier de forte epaisseur et toile de machine a papier servant a la production de ce papier
EP99969755A EP1153170B1 (fr) 1998-09-30 1999-09-21 Papier de forte epaisseur et toile de machine a papier servant a la production de ce papier
BR9914223-6A BR9914223A (pt) 1998-09-30 1999-09-21 Papel de elevado corpo e correia de fabricação de papel para sua produção
JP2000572452A JP4405677B2 (ja) 1998-09-30 1999-09-21 大きい厚さを有する紙およびその紙を抄造するための抄紙ベルト
DE69913741T DE69913741T2 (de) 1998-09-30 1999-09-21 Dickes papier und papiermachergewebe zu seiner herstellung
KR1020017003910A KR20010075403A (ko) 1998-09-30 1999-09-21 제지 벨트
NZ510468A NZ510468A (en) 1998-09-30 1999-09-21 High caliper papermaking belt having a reinforcing structure with elliptical deflection conduits

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US16588898A 1998-09-30 1998-09-30
US09/165,888 1998-09-30

Publications (1)

Publication Number Publication Date
WO2000019014A1 true WO2000019014A1 (fr) 2000-04-06

Family

ID=22600891

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1999/021877 WO2000019014A1 (fr) 1998-09-30 1999-09-21 Papier de forte epaisseur et toile de machine a papier servant a la production de ce papier

Country Status (12)

Country Link
EP (1) EP1153170B1 (fr)
JP (2) JP4405677B2 (fr)
KR (1) KR20010075403A (fr)
CN (1) CN1138036C (fr)
AT (1) ATE256783T1 (fr)
AU (1) AU745387B2 (fr)
BR (1) BR9914223A (fr)
CA (1) CA2344538C (fr)
DE (1) DE69913741T2 (fr)
ES (1) ES2209555T3 (fr)
NZ (1) NZ510468A (fr)
WO (1) WO2000019014A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003000002A1 (fr) * 2001-06-20 2003-01-03 Voith Paper Patent Gmbh Procede et dispositif pour produire une bande de matiere fibreuse pourvue d'une structure superficielle tridimensionnelle
JP2003531308A (ja) * 2000-04-27 2003-10-21 ザ プロクター アンド ギャンブル カンパニー 切断耐性粒子を有する吸収性シート材料及びその作成方法
US8852397B2 (en) 2009-01-28 2014-10-07 Georgia-Pacific Consumer Products Lp Methods of making a belt-creped absorbent cellulosic sheet prepared with a perforated polymeric belt
US10704203B2 (en) 2013-11-14 2020-07-07 Gpcp Ip Holdings Llc Absorbent sheets having high absorbency and high caliper, and methods of making soft, absorbent sheets
WO2021059085A1 (fr) * 2019-09-24 2021-04-01 Gpcp Ip Holdings Llc Courroies de fabrication de papier ayant des ouvertures décalées, procédés de fabrication de papier utilisant des courroies ayant des ouvertures décalées, et produits en papier fabriqués à partir de celles-ci

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7462257B2 (en) * 2004-12-21 2008-12-09 Kimberly-Clark Worldwide, Inc. Method for producing wet-pressed, molded tissue products

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0135231A1 (fr) * 1983-08-23 1985-03-27 The Procter & Gamble Company Membre flexible et procédé pour sa fabrication
WO1997026407A1 (fr) * 1996-01-19 1997-07-24 The Procter & Gamble Company Papier possedant de meilleures caracteristiques en ce qui concerne les trous d'aiguilles et bande continue destinee a la fabrication de ce papier

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0135231A1 (fr) * 1983-08-23 1985-03-27 The Procter & Gamble Company Membre flexible et procédé pour sa fabrication
WO1997026407A1 (fr) * 1996-01-19 1997-07-24 The Procter & Gamble Company Papier possedant de meilleures caracteristiques en ce qui concerne les trous d'aiguilles et bande continue destinee a la fabrication de ce papier

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003531308A (ja) * 2000-04-27 2003-10-21 ザ プロクター アンド ギャンブル カンパニー 切断耐性粒子を有する吸収性シート材料及びその作成方法
WO2003000002A1 (fr) * 2001-06-20 2003-01-03 Voith Paper Patent Gmbh Procede et dispositif pour produire une bande de matiere fibreuse pourvue d'une structure superficielle tridimensionnelle
EP1626122A1 (fr) * 2001-06-20 2006-02-15 Voith Paper Patent GmbH Procédé et dispositif pour produire une bande de matière fibreuse pourvue d'une structure superficielle tridimensionelle
EP1626121A1 (fr) * 2001-06-20 2006-02-15 Voith Paper Patent GmbH Procédé et dispositif pour produire une bande de matière fibreuse pourvue d'une structure superficielle tridimensionelle
US7291249B2 (en) 2001-06-20 2007-11-06 Voith Paper Patent Gmbh Apparatus for the manufacture of a structured fiber web
US8968516B2 (en) 2004-04-14 2015-03-03 Georgia-Pacific Consumer Products Lp Methods of making a belt-creped absorbent cellulosic sheet prepared with a perforated polymeric belt
US9017517B2 (en) 2004-04-14 2015-04-28 Georgia-Pacific Consumer Products Lp Method of making a belt-creped, absorbent cellulosic sheet with a perforated belt
US9388534B2 (en) 2004-04-14 2016-07-12 Georgia-Pacific Consumer Products Lp Method of making a belt-creped, absorbent cellulosic sheet with a perforated belt
US8852397B2 (en) 2009-01-28 2014-10-07 Georgia-Pacific Consumer Products Lp Methods of making a belt-creped absorbent cellulosic sheet prepared with a perforated polymeric belt
US10704203B2 (en) 2013-11-14 2020-07-07 Gpcp Ip Holdings Llc Absorbent sheets having high absorbency and high caliper, and methods of making soft, absorbent sheets
WO2021059085A1 (fr) * 2019-09-24 2021-04-01 Gpcp Ip Holdings Llc Courroies de fabrication de papier ayant des ouvertures décalées, procédés de fabrication de papier utilisant des courroies ayant des ouvertures décalées, et produits en papier fabriqués à partir de celles-ci
US11578460B2 (en) 2019-09-24 2023-02-14 Gpcp Ip Holdings Llc Papermaking belts having offset openings, papermaking processes using belts having offset openings, and paper products made therefrom

Also Published As

Publication number Publication date
AU745387B2 (en) 2002-03-21
JP2002525455A (ja) 2002-08-13
DE69913741T2 (de) 2004-12-09
JP2010007224A (ja) 2010-01-14
ES2209555T3 (es) 2004-06-16
DE69913741D1 (de) 2004-01-29
CA2344538C (fr) 2006-07-25
CA2344538A1 (fr) 2000-04-06
EP1153170A1 (fr) 2001-11-14
BR9914223A (pt) 2001-06-26
AU6055499A (en) 2000-04-17
NZ510468A (en) 2003-07-25
EP1153170B1 (fr) 2003-12-17
CN1319150A (zh) 2001-10-24
KR20010075403A (ko) 2001-08-09
CN1138036C (zh) 2004-02-11
JP4405677B2 (ja) 2010-01-27
ATE256783T1 (de) 2004-01-15

Similar Documents

Publication Publication Date Title
US7691229B2 (en) High caliper web and web-making belt for producing the same
JP4382042B2 (ja) ランダムに分配されたセルロース繊維及びランダムでなく分配された合成繊維を含む単一繊維構造体を作製するための方法及びそれにより作製された単一繊維構造体
EP0912801B1 (fr) Procede de fabrication de papier soie en pressage humide
US5776307A (en) Method of making wet pressed tissue paper with felts having selected permeabilities
JP4382043B2 (ja) セルロース繊維及び合成繊維を含む単一繊維構造体及びその作成方法
US5714041A (en) Papermaking belt having semicontinuous pattern and paper made thereon
JP2010007224A (ja) 大きい厚さを有する紙およびその紙を抄造するための抄紙ベルト
MXPA01003328A (en) High caliper paper and papermaking belt for producing the same
CA2206750C (fr) Toile de machine a papier a motif semi-continu et papier obtenu

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 99811281.X

Country of ref document: CN

AK Designated states

Kind code of ref document: A1

Designated state(s): AE AL AM AT AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ CZ DE DE DK DK DM EE ES FI FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SK SL TJ TM TR TT UA UG UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 510468

Country of ref document: NZ

ENP Entry into the national phase

Ref document number: 2344538

Country of ref document: CA

Ref document number: 2344538

Country of ref document: CA

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1020017003910

Country of ref document: KR

ENP Entry into the national phase

Ref document number: 2000 572452

Country of ref document: JP

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 60554/99

Country of ref document: AU

WWE Wipo information: entry into national phase

Ref document number: PA/a/2001/003328

Country of ref document: MX

WWE Wipo information: entry into national phase

Ref document number: 1999969755

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

WWP Wipo information: published in national office

Ref document number: 1020017003910

Country of ref document: KR

WWP Wipo information: published in national office

Ref document number: 1999969755

Country of ref document: EP

WWG Wipo information: grant in national office

Ref document number: 60554/99

Country of ref document: AU

WWG Wipo information: grant in national office

Ref document number: 1020017003910

Country of ref document: KR

WWG Wipo information: grant in national office

Ref document number: 1999969755

Country of ref document: EP