Patent Publication Number: US-7585395-B2

Title: Structured forming fabric

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This is a continuation-in-part of U.S. patent application Ser. No. 10/768,550, entitled “APPARATUS FOR AND PROCESS OF MATERIAL WEB FORMATION ON A STRUCTURED FABRIC IN A PAPER MACHINE”, filed Jan. 30, 2004 now U.S. Pat. No. 7,387,706. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a method of forming a structured fiber web on a paper machine, and, more particularly, to a method and apparatus of forming a structured fiber web on a structured forming fabric in a paper machine. 
   2. Description of the Related Art 
   In a wet molding process, a structured fabric in a Crescent Former configuration impresses a three dimensional surface on a web while the fibrous web is still wet. Such an invention is disclosed in International Publication No. WO 03/062528 A1. A suction box is disclosed for the purpose of shaping the fibrous web while wet to generate the three dimensional structure by removing air through the structural fabric. It is a physical displacement of portions of the fibrous web that leads to the three dimensional surface. Similar to the aforementioned method, a through air drying (TAD) technique is disclosed in U.S. Pat. No. 4,191,609. The TAD technique discloses how an already formed web is transferred and molded into an impression fabric. The transformation takes place on a web having a sheet solids level greater than 15%. This results in a low density pillow area in the fibrous web. These pillow areas are of a low basis weight since the already formed web is expanded to fill the valleys thereof. The impression of the fibrous web into a pattern, on an impression fabric, is carried out by passing a vacuum through the impression fabric to mold the fibrous web. 
   It is known to form a fiber web in a wet molding process using a structured fabric to impress a three dimensional surface on the web while the fibrous web is still wet. Such an invention is disclosed in International Publication No. WO 03/062528 A1. It is known to use forming fabrics, which have a load bearing layer and a sculptured layer wherein impression knuckles are formed, which imprint the sheet to increase the surface contour. Such an invention is disclosed in U.S. Pat. No. 5,429,686. However, this patent does not teach the creation of pillows on a sheet that are required for effective dewatering in through air drying (TAD) applications and in particular of an ATMOS™ papermaking machine. U.S. Pat. No. 6,237,644 teaches the use of fabrics, which are woven with a lattice pattern of at least three yarns oriented in both warp and weft. This reference teaches the use of a pattern fabric to provide shallow craters in distinct patterns. The physical displacement of portions of the fibrous web is a technique utilized to lead to a three-dimensional surface. A TAD technique is disclosed in U.S. Pat. No. 4,191,609. The TAD technique discloses how an already formed web is transferred and molded into an impression fabric. The transformation takes place on a web having a sheet solids level greater than 15%. This results in a low density pillow area in the fibrous web having a low basis weight, since the already formed web is expanded to fill the valleys. The impressions of the fibrous web into a pattern is carried out by passing a vacuum through the impression fabric to mold the fibrous web. 
   Prior art weave patterns such as the M weave illustrated in  FIGS. 19-21  and the G weave shown in  FIGS. 22-24  illustrate prior art fabrics that limit the amount of bulk that can be built into the fibrous web due to the shallow depth of the pockets. The weave patterns of the M weave and G weave are each based on a 5 by 5 pattern, which serves to define the location and shape of pockets. The pockets in these fabrics are shown as the darkened areas in  FIGS. 19 and 22 . These pockets are of such shape and depth that the bulk that can go therein is limited to less than a desired amount. 
   What is needed in the art is a structured forming fabric that will provide increased caliper, bulk and absorbency in tissue and toweling formed thereon. 
   SUMMARY OF THE INVENTION 
   The present invention provides a method of producing a structured fibrous web having a high basis weight pillow area of low density on a paper machine using a woven structured fabric. 
   The present invention consists in one form of a fabric for use by a papermaking machine, the fabric including a plurality of weft yarns, a plurality of warp yarns, and a woven fabric resulting from a repeating pattern of the weft yarns and warp yarns. Each of the weft yarn in the repeating pattern having a sequence of starting at a starting point then sequentially going over three adjacent warp yarns, under one warp yarn, over one warp yarn, under three warp yarns, over one warp yarn and under one warp yarn, the sequence then repeating. 
   An advantage of the present invention is that the forming fabric has pockets formed by warp yarns that float over three cross-directional yarns and weft floats over three machine direction yarns for the manufacture of bulky tissue. 
   Another advantage of the present invention is that it creates an improved surface area on a bulky tissue sheet and improved machine performance in making the tissue sheet. 
   Yet another advantage of the present invention is the perfect formation with high density pillow areas using the ATMOS™ concept, where the forming of the sheet takes place on the structured fabric. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
       FIG. 1  is a cross-sectional schematic diagram illustrating the formation of a structured web using an embodiment of a method of the present invention; 
       FIG. 2  is a cross-sectional view of a portion of a structured web of a prior art method; 
       FIG. 3  is a cross-sectional view of a portion of the structured web of an embodiment of the present invention as made on the machine of  FIG. 1 ; 
       FIG. 4  illustrates the web portion of  FIG. 2  having subsequently gone through a press drying operation; 
       FIG. 5  illustrates a portion of the fiber web of the present invention of  FIG. 3  having subsequently gone through a press drying operation; 
       FIG. 6  illustrates a resulting fiber web of the forming section of the present invention; 
       FIG. 7  illustrates the resulting fiber web of the forming section of a prior art method; 
       FIG. 8  illustrates the moisture removal of the fiber web of the present invention; 
       FIG. 9  illustrates the moisture removal of the fiber web of a prior art structured web; 
       FIG. 10  illustrates the pressing points on a fiber web of the present invention; 
       FIG. 11  illustrates pressing points of prior art structured web; 
       FIG. 12  illustrates a schematical cross-sectional view of an embodiment of a papermaking machine of the present invention; 
       FIG. 13  illustrates a schematical cross-sectional view of another embodiment of a papermaking machine of the present invention; 
       FIG. 14  illustrates a schematical cross-sectional view of another embodiment of a papermaking machine of the present invention; 
       FIG. 15  illustrates a schematical cross-sectional view of another embodiment of a papermaking machine of the present invention; 
       FIG. 16  illustrates a schematical cross-sectional view of another embodiment of a papermaking machine of the present invention; 
       FIG. 17  illustrates a schematical cross-sectional view of another embodiment of a papermaking machine of the present invention; and 
       FIG. 18  illustrates a schematical cross-sectional view of another embodiment of a papermaking machine of the present invention. 
       FIG. 19  is a prior art woven fabric known as an M weave fabric; 
       FIG. 20  is a schematical view of the positioning of the weft and warp yarns of the woven fabric of  FIG. 19 ; 
       FIG. 21  is a schematical representation of the routing of the warp yarns of the woven fabric of  FIGS. 19 and 20 ; 
       FIG. 22  is a prior art woven fabric known as an G weave fabric; 
       FIG. 23  is a schematical view of the positioning of the weft and warp yarns of the woven fabric of  FIG. 22 ; 
       FIG. 24  is a schematical representation of the routing of the warp yarns of the woven fabric of  FIGS. 22 and 23 ; 
       FIG. 25  is an illustration of the weave pattern of the woven fabric of  FIG. 1 ; 
       FIG. 26  is a schematical view of the warp yarns as they cross the weft yarns of the woven fabric of  FIGS. 1 and 25 ; 
       FIG. 27  illustrates a weave pattern of the warp and/or weft yarn of the woven fabric of FIGS.  1  and  25 - 26 ; 
       FIG. 28  is a paper side view of the woven fabric of FIGS.  1  and  25 - 27 ; 
       FIG. 29  is an opposite side view of the woven fabric of FIGS.  1  and  25 - 29 ; and 
       FIG. 30  is an impression made of the paper side of the woven fabric of FIGS.  1  and  25 - 29 . 
   

   Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to the drawings, and more particularly to  FIG. 1 , there is a fibrous web machine  20  including a headbox  22  that discharges a fibrous slurry  24  between a forming fabric  26  and a structured fabric  28 . Rollers  30  and  32  direct fabric  26  in such a manner that tension is applied thereto, against slurry  24  and structured fabric  28 . Structured fabric  28  is supported by forming roll  34  which rotates with a surface speed that matches the speed of structured fabric  28  and forming fabric  26 . Structured fabric  28  has peaks  28   a  and valleys  28   b , which give a corresponding structure to web  38  formed thereon. Structured fabric  28  travels in direction W, and as moisture M is driven from fibrous slurry  24 , structured fibrous web  38  takes form. Moisture M that leaves slurry  24  travels through forming fabric  26  and is collected in save-all  36 . Fibers in fibrous slurry  24  collect predominately in valleys  28   b  as web  38  takes form. 
   Structured fabric  28  includes warp and weft yarns interwoven on a textile loom. Structured fabric  28  may be woven flat or in an endless form. The final mesh count of structured fabric  28  lies between 95×120 and 26×20. For the manufacture of toilet tissue, the preferred mesh count is 51×36 or higher and more preferably 58×44 or higher. For the manufacturer of paper towels, the preferred mesh count is 42×31 or lower, and more preferably 36×30 or lower. Structured fabric  28  may have a repeated pattern of  4  shed and above repeats, preferably  5  shed or greater repeats. The warp yarns of structured fabric  28  have diameters of between 0.12 mm and 0.70 mm, and weft yarns have diameters of between 0.15 mm and 0.60 mm. The pocket depth, which is the offset between peak  28   a  and valley  28   b  is between approximately 0.07 mm and 0.60 mm. Yarns utilized in structured fabric  28  may be of any cross-sectional shape, for example, round, oval or flat. The yarns of structured fabric  28  can be made of thermoplastic or thermoset polymeric materials of any color. The surface of structured fabric  28  can be treated to provide a desired surface energy, thermal resistance, abrasion resistance and/or hydrolysis resistance. A printed design, such as a screen printed design, of polymeric material can be applied to structured fabric  28  to enhance its ability to impart an aesthetic pattern into web  38  or to enhance the quality of web  38 . Such a design may be in the form of an elastomeric cast structure similar to the Spectra® membrane described in another patent application. Structured fabric  28  has a top surface plane contact area at peak  28   a  of 10% or higher, preferably 20% or higher, and more preferably 30% depending upon the particular product being made. The contact area on structured web  28  at peak  28   a  can be increased by abrading the top surface of structured fabric  28  or an elastomeric cast structure can be formed thereon having a flat top surface. The top surface may also be hot calendered to increase the flatness. 
   Forming roll  34  is preferably solid. Moisture travels through forming fiber  26  but not through structured fabric  28 . This advantageously forms structured fibrous web  38  into a more bulky or absorbent web than the prior art. 
   Prior art methods of moisture removal, remove moisture through a structured fabric by way of negative pressure. It results in a cross-sectional view as seen in  FIG. 2 . Prior art structured web  40  has a pocket depth D which corresponds to the dimensional difference between a valley and a peak. The valley occurring at the point where measurement C occurs and the peak occurring at the point where measurement A is taken. A top surface thickness A is formed in the prior art method. Sidewall dimension B and pillow thickness C of the prior art result from moisture drawn through a structured fabric. Dimension B is less than dimension A and dimension C is less than dimension B in the prior art structure. 
   In contrast, structured web  38 , as illustrated in  FIGS. 3 and 5 , have for discussion purposes, a pocket depth D that is similar to the prior art. However, sidewall thickness B′ and pillow thickness C′ exceed the comparable dimensions of web  40 . This advantageously results from the forming of structural web  38  on structured fabric  28  at low consistency and the removal of moisture is an opposite direction from the prior art. This results in a thicker pillow dimension C′. Even after fiber web  38  goes through a drying press operation, as illustrated in  FIG. 5 , dimension C′ is substantially greater than A p ′. Advantageously, the fiber web resulting from the present invention has a higher basis weight in the pillow areas as compared to prior art. Also, the fiber to fiber bonds are not broken as they can be in impression operations, which expand the web into the valleys. 
   According to prior art an already formed web is vacuum transferred into a structured fabric. The sheet must then expand to fill the contour of the structured fabric. In doing so, fibers must move apart. Thus the basis weight is lower in these pillow areas and therefore the thickness is less than the sheet at point A. 
   Now, referring to  FIGS. 6 to 11  the process will be explained by simplified schematic drawings. 
   As shown in  FIG. 6 , fibrous slurry  24  is formed into a web  38  with a structure inherent in the shape of structured fabric  28 . Forming fabric  26  is porous and allows moisture to escape during forming. Further, water is removed as shown in  FIG. 8 , through dewatering fabric  82 . The removal of moisture through fabric  82  does not cause a compression of pillow areas C′ in the forming web, since pillow areas C′ reside in the structure of structured fabric  28 . 
   The prior art web shown in  FIG. 7 , is formed with a conventional forming fabric as between two conventional forming fabrics in a twin wire former and is characterized by a flat uniform surface. It is this fiber web that is given a three-dimensional structure by a wet shaping stage, which results in the fiber web that is shown in  FIG. 2 . A conventional tissue machine that employs a conventional press fabric will have a contact area approaching 100%. Normal contact area of the structured fiber, as in this present invention, or as on a TAD machine, is typically much lower than that of a conventional machine, it is in the range of 15 to 35% depending on the particular pattern of the product being made. 
   In  FIGS. 9 and 11  a prior art web structure is shown where moisture is drawn through a structured fabric  33  causing the web, as shown in  FIG. 7 , to be shaped and causing pillow area C to have a low basis weight as the fibers in the web are drawn into the structure. The shaping can be done by performing pressure or underpressure to the web  40  forcing the web to follow the structure of the structured fabric  33 . This additionally causes fiber tearing as they are moved into pillow area C. Subsequent pressing at the Yankee dryer  52 , as shown in  FIG. 11 , further reduces the basis weight in area C. In contrast, water is drawn through dewatering fabric  82  in the present invention, as shown in  FIG. 8 , preserving pillow areas C′. Pillow areas C′ of  FIG. 10 , is an unpressed zone, which is supported on structured fabric  28 , while pressed against Yankee  52 . Pressed zone A′ is the area through which most of the pressure applied is transferred. Pillow area C′ has a higher basis weight than that of the illustrated prior art structures. 
   The increased mass ratio of the present invention, particularly the higher basis weight in the pillow areas carries more water than the compressed areas, resulting in at least two positive aspects of the present invention over the prior art, as illustrated in  FIGS. 10 and 11 . First, it allows for a good transfer of the web to the Yankee surface  52 , since the web has a relatively lower basis weight in the portion that comes in contact with the Yankee surface  52 , at a lower overall sheet solid content than had been previously attainable, because of the lower mass of fibers that comes in contact with the Yankee dryer  52 . The lower basis weight means that less water is carried to the contact points with the Yankee dryer  52 . The compressed areas are dryer than the pillow areas, thereby allowing an overall transfer of the web to another surface, such as a Yankee dryer  52 , with a lower overall web solids content. Secondly, the construct allows for the use of higher temperatures in the Yankee hood  54  without scorching or burning of the pillow areas, which occurs in the prior art pillow areas. The Yankee hood  54  temperatures are often greater than 350° C. and preferably greater than 450° C. and even more preferably greater than 550° C. As a result the present invention can operate at lower average pre-Yankee press solids than the prior art, making more full use of the capacity of the Yankee Hood drying system. The present invention can allows the solids content of web  38  prior to the Yankee dryer to run at less than 40%, less than 35% and even as low as 25%. 
   Due to the formation of the web  38  with the structured fabric  28  the pockets of the fabric  28  are fully filled with fibers. 
   Therefore, at the Yankee surface  52  the web  38  has a much higher contact area, up to approx. 100%, as compared to the prior art because the web  38  on the side contacting the Yankee surface  52  is almost flat. At the same time the pillow areas C′ of the web  38  maintain unpressed, because they are protected by the valleys of the structured fabric  28  ( FIG. 10 ). Good results in drying efficiency were obtained only pressing 25% of the web. 
   As can be seen in  FIG. 11  the contact area of the prior art web  40  to the Yankee surface  52  is much lower as compared to the one of the web  38  manufactured according to the invention. 
   The lower contact area of the prior art web  40  results from the shaping of the web  40  that now follows the structure of the structured fabric  33 . 
   Due to the less contact area of the prior art web  40  to the Yankee surface  52  the drying efficiency is less. 
   Now, additionally referring to  FIG. 12 , there is shown an embodiment of the process where a structured fiber web  38  is formed. Structured fabric  28  carries a three dimensional structured web  38  to an advanced dewatering system  50 , past suction box  67  and then to a Yankee roll  52  where the web is transferred to Yankee roll  52  and hood section  54  for additional drying and creping before winding up on a reel (not shown). 
   A shoe press  56  is placed adjacent to structured fabric  28 , holding it in a position proximate Yankee roll  52 . Structured web  38  comes into contact with Yankee roll  52  and transfers to a surface thereof, for further drying and subsequent creping. 
   A vacuum box  58  is placed adjacent to structured fabric  28  to achieve a solids level of 15-25% on a nominal 20 gsm web running at −0.2 to −0.8 bar vacuum with a preferred operating level of −0.4 to −0.6 bar. Vacuum box  58  is a differential pressure arrangement  58  that provides for a pressure differential as it acts on fabric  28 , web  38 , and fabric  82 . Web  38 , which is carried by structured fabric  28 , contacts dewatering fabric  82  and proceeds toward vacuum roll  60 . Vacuum roll  60  is a supporting structure  60  having a support surface. Vacuum roll  60  operates at a vacuum level of −0.2 to −0.8 bar with a preferred operating level of at least −0.4 bar. Hot air hood  62  is optionally fit over vacuum roll  60  to improve dewatering. If for example, a commercial Yankee drying cylinder with 44 mm steel thickness and a conventional hood with an air blowing speed of 145 m/s is used production speeds of 1400 mlmin or more for towel paper and 1700 mlmin or more for toilet paper are used. 
   Optionally a steam box can be installed instead of the hood  62  supplying steam to the web  38 . Preferably the steam box has a sectionalized design to influence the moisture re-dryness cross profile of the web  38 . The length of the vacuum zone inside the vacuum roll  60  can be from 200 mm to 2,500 mm, with a preferable length of 300 mm to 1,200 mm and an even more preferable length of between 400 mm to 800 mm. The solids level of web  38  leaving suction roll  60  is 25% to 55% depending on installed options. A vacuum box  67  and hot air supply  65  can be used to increase web  38  solids after vacuum roll  60  and prior to Yankee roll  52 . Wire turning roll  69  can also be a suction roll with a hot air supply hood. Roll  56  includes a shoe press with a shoe width of 80 mm or higher, preferably 120 mm or higher, with a maximum peak pressure of less than 2.5 MPa. To create an even longer nip to facilitate the transfer of web  38  to Yankee  52 , web  38  carried on structured fabric  28  can be brought into contact with the surface of Yankee roll  52  prior to the press nip associated with shoe press  56 . Further, the contact can be maintained after structured fabric  28  travels beyond press  56 . 
   Dewatering fabric  82  may have a permeable woven base fabric connected to a batt layer. The base fabric includes machine direction yarns and cross-directional yarns. The machine direction yarn is a 3 ply multifilament twisted yarn. The cross-direction yarn is a monofilament yarn. The machine direction yarn can also be a monofilament yarn and the construction can be of a typical multilayer design. In either case, the base fabric is needled with a fine batt fiber having a weight of less than or equal to 700 gsm, preferably less than or equal to 150 gsm and more preferably less than or equal to 135 gsm. The batt fiber encapsulates the base structure giving it sufficient stability. The needling process can be such that straight through channels are created. The sheet contacting surface is heated to improve its surface smoothness s. The cross-sectional area of the machine direction yarns is larger than the cross-sectional area of the cross-direction yarns. The machine direction yarn is a multifilament yarn that may include thousands of fibers. The base fabric is connected to a batt layer by a needling process that results in straight through drainage channels. 
   In another embodiment of dewatering fabric  82  there is included a fabric layer, at least two batt layers, an anti-rewetting layer and an adhesive. The base fabric is substantially similar to the previous description. At least one of the batt layers include a low melt bi-compound fiber to supplement fiber to fiber bonding upon heating. On one side of the base fabric, there is attached an anti-rewetting layer, which may be attached to the base fabric by an adhesive, a melting process or needling wherein the material contained in the anti-rewet layer is connected to the base fabric layer and a batt layer. The anti-rewetting layer is made of an elastomeric material thereby forming elastomeric membrane, which has openings therethrough. 
   The batt layers are needled to thereby hold dewatering fabric  82  together. This advantageously leaves the batt layers with many needled holes therethrough. The anti-rewetting layer is porous having water channels or straight through pores therethrough. 
   In yet an other embodiment of dewatering fabric  82 , there is a construct substantially similar to that previously discussed with an addition of a hydrophobic layer to at least one side of de-watering fabric  82 . The hydrophobic layer does not absorb water, but it does direct water through pores therein. 
   In yet another embodiment of dewatering fabric  82 , the base fabric has attached thereto a lattice grid made of a polymer, such as polyurethane, that is put on top of the base fabric. The grid may be put on to the base fabric by utilizing various known procedures, such as, for example, an extrusion technique or a screen-printing technique. The lattice grid may be put on the base fabric with an angular orientation relative to the machine direction yarns and the cross direction yarns. Although this orientation is such that no part of the lattice is aligned with the machine direction yarns, other orientations can also be utilized. The lattice can have a uniform grid pattern, which can be discontinuous in part. Further, the material between the interconnections of the lattice structure may take a circuitous path rather than being substantially straight. The lattice grid is made of a synthetic, such as a polymer or specifically a polyurethane, which attaches itself to the base fabric by its natural adhesion properties. 
   In yet another embodiment of dewatering fabric  82  there is included a permeable base fabric having machine direction yarns and cross-direction yarns, that are adhered to a grid. The grid is made of a composite material the may be the same as that discussed relative to a previous embodiment of dewatering fabric  82 . The grid includes machine direction yarns with a composite material formed therearound. The grid is a composite structure formed of composite material and machine direction yarns. The machine direction yarns may be pre-coated with a composite before being placed in rows that are substantially parallel in a mold that is used to reheat the composite material causing it to re-flow into a pattern. Additional composite material may be put into the mold as well. The grid structure, also known as a composite layer, is then connected to the base fabric by one of many techniques including laminating the grid to the permeable fabric, melting the composite coated yarn as it is held in position against the permeable fabric or by re-melting the grid onto the base fabric. Additionally, an adhesive may be utilized to attach the grid to permeable fabric. 
   The batt fiber may include two layers, an upper and a lower layer. The batt fiber is needled into the base fabric and the composite layer, thereby forming a dewatering fabric  82  having at least one outer batt layer surface. Batt material is porous by its nature, additionally the needling process not only connects the layers together, it also creates numerous small porous cavities extending into or completely through the structure of dewatering fabric  82 . 
   Dewatering fabric  82  has an air permeability of from 5 to 100 cubic feet/minute preferably 19 cubic feet/minute or higher and more preferably 35 cubic feet/minute or higher. Mean pore diameters in dewatering fabric  82  are from 5 to 75 microns, preferably 25 microns or higher and more preferably 35 microns or higher. The hydrophobic layers can be made from a synthetic polymeric material, a wool or a polyamide, for example, nylon 6. The anti-rewet layer and the composite layer may be made of a thin elastomeric permeable membrane made from a synthetic polymeric material or a polyamide that is laminated to the base fabric. 
   The batt fiber layers are made from fibers ranging from 0.5 d-tex to 22 d-tex and may contain a low melt bi-compound fiber to supplement fiber to fiber bonding in each of the layers upon heating. The bonding may result from the use of a low temperature meltable fiber, particles and/or resin. The dewatering fabric can be less than 2.0 millimeters, or less than 1.50 millimeters, or less than 1.25 millimeters or less than 1.0 millimeter thick. 
   Preferred embodiments of the dewatering fabric  82  are also described in the PCT/EP2004/053688 and PCT/EP2005/050198 which are herewith incorporated by reference. 
   Now, additionally referring to  FIG. 13 , there is shown yet another embodiment of the present invention, which is substantially similar to the invention illustrated in  FIG. 12 , except that instead of hot air hood  62 , there is a belt press  64 . Belt press  64  includes a permeable belt  66  capable of applying pressure to the non-sheet contacting side of structured fabric  28  that carries web  38  around suction roll  60 . Belt  66  is also known as a pressure producing element  66 . Fabric  66  of belt press  64  is also known as an extended nip press belt or a link fabric, which can run at 60 KN/m fabric tension with a pressing length that is longer than the suction zone of roll  60 . 
   Preferred embodiments of the fabric  66  and the required operation conciliation are also described in PCT/EP2004/053688 and PCT/EP2005/050198 which are herewith incorporated by reference. 
   The above mentioned references are also fully applicable for dewatering fabrics  82  and press fabrics  66  described in the further embodiments. 
   While pressure is applied to structured fabric  28 , the high fiber density pillow areas in web  38  are protected from that pressure as they are contained within the body of structured fabric  28 , as they are in the Yankee nip. 
   Belt  66  is a specially designed Extended Nip Press Belt  66 , made of, for example reinforced polyurethane and/or a spiral link fabric. Belt  66  is permeable thereby allowing air to flow therethrough to enhance the moisture removing capability of belt press  64 . Moisture is drawn from web  38  through dewatering fabric  82  and into vacuum roll  60 . 
   Belt  66  provides a low level of pressing in the range of 50-300 KPa and preferably greater than 100 KPa. This allows a suction roll with a 1.2 meter diameter to have a fabric tension of greater than 30 KN/m and preferably greater than 60 KN/m. The pressing length of permeable belt  66  against fabric  28 , which is indirectly supported by vacuum roll  60 , is at least as long as a suction zone in roll  60 . Although the contact portion of belt  66  can be shorter than the suction zone. 
   Permeable belt  66  has a pattern of holes therethrough, which may, for example, be drilled, laser cut, etched formed or woven therein. Permeable belt  66  may be monoplanar without grooves. In one embodiment, the surface of belt  66  has grooves and is placed in contact with fabric  28  along a portion of the travel of permeable belt  66  in belt press  64 . Each groove connects with a set of the holes to allow the passage and distribution of air in belt  66 . Air is distributed along the grooves, which constitutes an open area adjacent to contact areas, where the surface of belt  66  applies pressure against web  38 . Air enters permeable belt  66  through the holes and then migrates along the grooves, passing through fabric  28 , web  38  and fabric  82 . The diameter of the holes may be larger than the width of the grooves. The grooves may have a cross-section contour that is generally rectangular, triangular, trapezoidal, semi-circular or semi-elliptical. The combination of permeable belt  66 , associated with vacuum roll  60 , is a combination that has been shown to increase sheet solids by at least 15%. 
   An example of another structure of belt  66  is that of a thin spiral link fabric, which can be a reinforcing structure within belt  66  or the spiral link fabric will itself serve as belt  66 . Within fabric  28  there is a three dimensional structure that is reflected in web  38 . Web  38  has thicker pillow areas, which are protected during pressing as they are within the body of structured fabric  28 . As such the pressing imparted by belt press assembly  64  upon web  38  does not negatively impact web quality, while it increases the dewatering rate of vacuum roll  60 . 
   Now, additionally referring to  FIG. 14 , which is substantially similar to the embodiment shown in  FIG. 13  with the addition of hot air hood  68  placed inside of belt press  64  to enhance the dewatering capability of belt press  64  in conjunction with vacuum roll  60 . 
   Now, additionally referring to  FIG. 15 , there is shown yet another embodiment of the present invention, which is substantially similar to the embodiment shown in  FIG. 13 , but including a boost dryer  70 , which encounters structured fabric  28 . Web  38  is subjected to a hot surface of boost driver  70 , structure web  38  rides around boost driver  70  with another woven fabric  72  riding on top of structured fabric  28 . On top of woven fabric  72  is a thermally conductive fabric  74 , which is in contact with both woven fabric  72  and a cooling jacket  76  that applies cooling and pressure to all fabrics and web  38 . Here again, the higher fiber density pillow areas in web  38  are protected from the pressure as they are contained within the body of structured fabric  28 . As such, the pressing process does not negatively impact web quality. The drying rate of boost dryer  70  is above 400 kg/hrm 2  and preferably above 500 kg/hrm 2 . The concept of boost dryer  70  is to provide sufficient pressure to hold web  38  against the hot surface of the dryer thus preventing blistering. Steam that is formed at the knuckle points fabric  28  passes through fabric  28  and is condensed on fabric  72 . Fabric  72  is cooled by fabric  74  that is in contact with the cooling jacket, which reduces its temperature to well below that of the steam. Thus the steam is condensed to avoid a pressure build up to thereby avoid blistering of web  38 . The condensed water is captured in woven fabric  72 , which is dewatered by dewatering device  75 . It has been shown that depending on the size of boost dryer  70 , the need for vacuum roll  60  can be eliminated. Further, depending upon the size of boost dryer  70 , web  38  may be creped on the surface of boost dryer  70 , thereby eliminating the need for Yankee dryer  52 . 
   Now, additionally referring to  FIG. 16 , there is shown yet another embodiment of the present invention substantially similar to the invention disclosed in  FIG. 13  but with an addition of an air press  78 , which is a four roll cluster press that is used with high temperature air and is referred to as an HPTAD for additional web drying prior to the transfer of web  38  to Yankee  52 . Four roll cluster press  78  includes a main roll and a vented roll and two cap rolls. The purpose of this cluster press is to provide a sealed chamber that is capable of being pressurized. The pressure chamber contains high temperature air, for example, 150° C. or higher and is at a significantly higher pressure than conventional TAD technology, for example, greater than 1.5 psi resulting in a much higher drying rate than a conventional TAD. The high pressure hot air passes through an optional air dispersion fabric, through web  38  and fabric  28  into a vent roll. The air dispersion fabric may prevent web  38  from following one of the four cap rolls. The air dispersion fabric is very open, having a permeability that equals or exceeds that of fabric  28 . The drying rate of the HPTAD depends on the solids content of web  38  as it enters the HPTAD. The preferred drying rate is at least 500 kg/hr/m 2 , which is a rate of at least twice that of conventional TAD machines. 
   Advantages of the HPTAD process are in the areas of improved sheet dewatering without a significant loss in sheet quality, compactness in size and energy efficiency. Additionally, it enables higher pre-Yankee solids, which increase the speed potential of the invention. Further, the compact size of the HPTAD allows for easy retrofit to an existing machine. The compact size of the HPTAD and the fact that it is a closed system means that it can be easily insulated and optimized as a unit to increase energy efficiency. 
   Now, additionally referring to  FIG. 17 , there is shown another embodiment of the present invention. This is significantly similar to  FIGS. 13 and 16  except for the addition of a two-pass HPTAD  80 . In this case, two vented rolls are used to double the dwell time of structured web  38  relative to the design shown in  FIG. 16 . An optional coarse mesh fabric may used as in the previous embodiment. Hot pressurized air passes through web  38  carried on fabric  28  and onto the two vent rolls. It has been shown that depending on the configuration and size of the HPTAD, that more than one HPTAD can be placed in series, which can eliminate the need for roll  60 . 
   Now, additionally referring to  FIG. 18 , a conventional Twin Wire Former  90  may be used to replace the Crescent Former shown in previous examples. The forming roll can be either a solid or open roll. If an open roll is used, care must be taken to prevent significant dewatering through the structured fabric to avoid losing basis weight in the pillow areas. The outer forming fabric  93  can be either a standard forming fabric or one such as that disclosed in U.S. Pat. No. 6,237,644. The inner forming fabric  91  must be a structured fabric  91  that is much coarser than the outer forming fabric. A vacuum box  92  may be needed to ensure that the web stays with structured wire  91  and does not go with outer wire  90 . Web  38  is transferred to structured fabric  28  using a vacuum device. The transfer can be a stationary vacuum shoe or a vacuum assisted rotating pick-up roll  94 . The second structured fabric  28  is at least the same coarseness and preferably courser than first structured fabric  91 . The process from this point is the same as one of the previously discussed processes. The registration of the web from the first structured fabric to the second structured fabric is not perfect, as such some pillows will lose some basis weight during the expansion process, thereby losing some of the benefit of the present invention. However, this process option allows for running a differential speed transfer, which has been shown to improve some sheet properties. Any of the arrangements for removing water discussed above as may be used with the Twin Wire Former arrangement and a conventional TAD. 
   The fiber distribution of web  38  in this invention is opposite that of the prior art, which is a result of removing moisture through the forming fabric and not through the structured fabric. The low density pillow areas are of relatively higher basis weight than the surrounding compressed zones, which is opposite of conventional TAD paper. This allows a high percentage of the fibers to remain uncompressed during the process. The sheet absorbency capacity as measured by the basket method, for a nominal 20 gsm web is equal to or greater than 12 grams water per gram of fiber and often exceeds 15 grams of water per gram fiber. The sheet bulk is equal to or greater than 10 cm 3 /gm and preferably greater than 13 cm 3 /gm. The sheet bulk of toilet tissue is expected to be equal to or greater than 13 cm 3 /gm before calendering. 
   With the basket method of measuring absorbency, five (5) grams of paper are placed into a basket. The basket containing the paper is then weighted and introduced into a small vessel of water at 20° C. for 60 seconds. After 60 seconds of soak time, the basket is removed from the water and allowed to drain for 60 seconds and then weighted again. The weight difference is then divided by the paper weight to yield the grams of water held per gram of fibers being absorbed and held in the paper. 
   Web  38  is formed from fibrous slurry  24  that headbox  22  discharges between forming fabric  26  and structured fabric  28 . Roll  34  rotates and supports fabrics  26  and  28  as web  38  forms. Moisture M flows through fabric  26  and is captured in save all  36 . It is the removal of moisture in this manner that serves to allow pillow areas of web  38  to retain a greater basis weight and therefore thickness than if the moisture were to be removed through structured fabric  28 . Sufficient moisture is removed from web  38  to allow fabric  26  to be removed from web  38  to allow web  38  to proceed to a drying stage. Web  38  retains the pattern of structured fabric  28  and any zonal permeability effects from fabric  26  that may be present. 
   Referring again to  FIG. 1 , there is shown a papermaking machine  20  including a headbox  22  that discharges a fibrous slurry  24  between forming fabric  26  and a woven structured fabric  28 . Rollers  30  and  32  direct fabric  26  in such a manner that tension is applied thereto, against slurry  24  and woven structured fabric  28 . Woven structured fabric  28  is supported by forming roll  34 , which rotates with a surface speed that matches the speed of woven structured fabric  28  and forming fabric  26 . Structured fabric  28  has peaks  28   a  and valleys  28   b , which give a corresponding structure to web  38  formed thereon. Structured fabric  28  travels in direction W, and as moisture M is driven from fibrous slurry  24 , a structured fibrous web  38  takes form. Moisture M leaves slurry  24  travels through forming fabric  26  and is collected in save-all  36 . Fibers in fibrous slurry  24  collect predominately in valleys  28   b  as web  38  takes form. 
   As slurry  24  comes from headbox  22  it has a very low consistency of approximately 0.1 to 0.5%. The consistency of web  38  increases to approximately 7% at the end of the forming section outlet. Structured fabric  28  carries web  38  from where it is first placed there by headbox  22  all of the way to a Yankee dryer to thereby provide a well defined paper structure for maximum bulk and absorbency capacity. Web  38  has exceptional caliper, bulk and absorbency, 30% higher than with a conventional TAD fabric used for producing paper towels. Excellent transfer of web  38  to the Yankee dryer takes place with the ATMOS™ system working at 33 to 37% dryness, which is a higher moisture content than the TAD of 60 to 75%. There is no dryness loss running in the ATMOS™ configuration, since structured fabric  28  has pocket depth (valleys) and not knuckles (peaks) there is no loss of intimacy between a dewatering fabric, web  38 , structured fabric  28  and the belt, which is key to reaching the desired dryness with the ATMOS™ system. 
   Now, additionally referring to  FIGS. 25-27 , woven structured fabric  28  includes warp and weft yarns that are interwoven on a textile loom. Structured fabric  28  may be woven flat or in endless form. Structured fabric  28  has a surface contact area on the web side of 15 to 40%, preferably 25 to 30% and most preferably approximately 28%. 
   As can be seen in  FIGS. 25 and 26 , repeating almost square pockets are formed because the weave pattern holds pockets to a deeper depth since there is a plane formed lower than the contact level that substantially surrounds the pocket. The pocket depth, which can be thought of as an offset between peak  28   a  and valley  28   b  occurs substantially across the pocket due to the weave pattern of the present invention. The boundaries of the pockets are shared with part of a boundary of another adjacent pocket formed in woven structured fabric  28 . This pocket depth and the size of the pocket leads to a pocket volume. Each pocket has a volume of from 1.0 mm 3  to 3.0 mm 3 , with a preferred volume of between 1.5 mm 3  to 2.5 mm 3 , and a most preferred volume of approximately 2.0 mm 3 . 
   Yarns utilized in woven structured fabric  28  may be of any cross-sectional shape, for example, round, oval, flattened or square. Yarns of woven structured fabric  28  can be made of thermoplastic or thermo-set polymeric materials of any color. Surface features  42  may be a flattened, protruding, depressed or other formation on the surface of individual warped and/or weft yarns. Such surface feature  42  may be applied after the weaving of woven structured fabric  28 . For example, the top surface may be hot calendared to increase the flatness. The permeability of woven structured fabric  28  is between 300 cfm and 1,600 cfm, with a preferred range of 500 cfm to 1,000 cfm, and a most preferred value of approximately 750 cfm. 
   The warp yarn pattern shown in  FIG. 27  is also reflective of the weft patterns. For example, in  FIG. 26  it can be seen that the pattern for warp yarn  1 , from top to bottom, is the same as the pattern for weft yarn  3  from left to right. Warp yarn  1  goes over weft yarn  1 , under weft yarn  2 , over weft yarn  3 , under weft yarns  4 ,  5  and  6 , over weft yarn  7 , under weft yarn  8  and then over weft yarns  9  and  10 . The patterns of the other yarns are described in a like matter from the information in  FIGS. 25 ,  26  and  27 . 
   Woven structured fabric  28  has a repeating pattern that is described by the ten weft and warp yarns of  FIGS. 25-27 . The fabric can be thought of as having a weave pattern that has offsets from a starting point for the 10 by 10 pattern. Any of the weaves illustrated in  FIG. 27  can be selected to demonstrate an offset of the pattern. For example, choosing yarn number  7  as defining a starting point has a zero offset from itself, yarn number  6  is offset by three intersecting yarns to the right, yarn  5  is offset by six positions from the starting position and yarn  4  is offset by nine positions to the right. In a like manner, yarn  3  is offset two, yarn  2  is offset five, yarn  1  is offset eight, yarn  10  is offset one, yarn  9  is offset four and yarn  8  is offset seven. Since the pattern is repeating the offsets can be measured from any of the yarns with a selected yarn being the starting point for the pattern. In a similar fashion, the offsets can be described as a negative offset, which can be thought of as a shift to the left of the pattern. It is noted that adjacent yarns are offset from each other by an odd number of positions from the intersecting yarns. And that the next adjacent yarns are offset by an even number of intersecting yarns. As mentioned previously the weave patterns shown in  FIG. 27  are equally applicable to either the weft or the warp directions of the pattern, thereby making the pattern of a symmetrical nature. 
   The pattern of the weave of the present invention advantageously has a pocket density of from 100 to 300 pockets per square inch and preferably from 150 to 300 pockets per square inch, and a most preferred value of approximately 200 pockets per square inch. Within each 10 by 10 yarn repeating pattern there is at least eight full pockets. The full pockets exist at the intersections of warp yarns  1  and  2  with weft yarns  3  and  4 , warp yarns  3  and  4  with weft yarns  7  and  8 , warp yarns  4  and  5  with weft yarns  4  and  5 , warp yarns  5  and  6  with weft yarns  1  and  2 , warp yarns  6  and  7  with weft yarns  8  and  9 , warp yarns  7  and  8  with weft yarns  5  and  6 , warp yarns  8  and  9  with weft yarns  2  and  3 , and warp yarns  9  and  10  with weft yarns  9  and  10 . As can be seen in  FIGS. 25 and 26  there are also a half pocket along each border of each the four sides of the repeating pattern, which serves to interconnect with a corresponding half of a pocket in the repeating design. 
   Structured fabric  28  has a surface contact area in the range of 15 to 40%, with a preferred range of 25 to 30% and a most preferred value of approximately 28%. The thickness of structured fabric  28  is in the range of 0.03 to 0.08 inches and preferably 0.04 to 0.06 inches, with a most preferred value of 0.05 inches. 
   As previously mentioned, the pockets are deeper than those of the prior art because they are on a plane lower than the contact level that surrounds each of these pockets. The use of woven structured fabric  28  with a papermaking machine  20 , as illustrated in  FIGS. 12-18 , is directed to a molding position on an ATMOS™ system, but may also find use on a conventional TAD, a transfer position on an E-TAD or a position on a Metso concept machine. 
   Views of the weave patterns are also shown in  FIGS. 28 and 29  with  FIG. 30  illustrating the possible impression view of the top of the structured fabric  28 .  FIG. 28  is a picture of the paper side weave and  FIG. 29  is a picture of the opposite side of structured fabric  28 .  FIGS. 28 and 29  are substantially similar since the weave patterns are of a symmetrical nature.  FIG. 30  shows an impression that illustrates the contact points of structured fabric  28 . The weft yarns are prouder than the warp yarns, which can reflect the relative sizes of the weft and warp yarns, the shaping of the yarns or use factors such as tension on structured fabric  28  while in use. 
   While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.