AU731653B2 - Paper structure having at least three regions, and apparatus and process for making the same - Google Patents

Paper structure having at least three regions, and apparatus and process for making the same Download PDF

Info

Publication number
AU731653B2
AU731653B2 AU18400/99A AU1840099A AU731653B2 AU 731653 B2 AU731653 B2 AU 731653B2 AU 18400/99 A AU18400/99 A AU 18400/99A AU 1840099 A AU1840099 A AU 1840099A AU 731653 B2 AU731653 B2 AU 731653B2
Authority
AU
Australia
Prior art keywords
web
region
elevation
felt
layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
AU18400/99A
Other versions
AU1840099A (en
Inventor
Paul Dennis Trokhan
Dean Van Phan
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Procter and Gamble Co
Original Assignee
Procter and Gamble Co
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
Priority claimed from AU27060/95A external-priority patent/AU704258C/en
Application filed by Procter and Gamble Co filed Critical Procter and Gamble Co
Priority to AU18400/99A priority Critical patent/AU731653B2/en
Publication of AU1840099A publication Critical patent/AU1840099A/en
Application granted granted Critical
Publication of AU731653B2 publication Critical patent/AU731653B2/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Description

IUM 1i 2815/91 Regulation 3.2(2)
AUSTRALIA
Patents Act 1990
ORIGINAL
COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: Invention Title: PAPER STRUCTURE HAVING AT LEAST THREE REGIONS, AND APPARATUS AND PROCESS FOR MAKING THE SAME The following statement is a full description of this invention, including the best method of performing it known to us I bi 1 PAPER STRUCTURE HAVING AT LEAST THREE REGIONS AND APPARATUS AND PROCESS FOR MAKING THE SAME This application is a divisional application of AU27060/95, the parent application. The parent application disclosed a number of aspects of the invention and various aspects have been the subject of separate divisional applications. The claims of the present application are directed to an aspect of the invention, namely a method of forming a paper web.
In order to fully describe this aspect of the invention, the other aspects of the invention are also described in the description. The phase "the present invention" or "the invention" refers to one or more of the various aspects of the invention.
The phrase "the present embodiment" or "the embodiment" or the like, refers to one or more exemplary embodiments of one or more of the various aspects of the invention.
FIELD OF THE INVENTION The present invention relates to a paper structure, such as a tissue paper web, having a transition region interconnecting relatively thinner regions disposed at different elevations. A web support apparatus and process for making such a paper web also form part of the present invention.
20 BACKGROUND OF THE INVENTION Paper structures, such as toilet tissue, paper towels, and facial tissue, are widely used throughout the home and industry. Many attempts have been e made to make such tissue products more consumer preferred. One approach to providing consumer preferred tissue products having bulk and flexibility is 25 illustrated in U.S. Patent 3,994,771 issued November 30, 1976 to Morgan et.
al. Improved bulk and flexibility may also be provided through bilaterally staggered compressed and uncompressed zones, as shown in U.S. Patent o 4,191,609 issued March 4, 1980 to Trokhan.
Another approach to making tissue products more consumer preferred S 30 is to dry the paper structure to impart greater bulk, tensile strength, and burst strength to the tissue products. Examples of paper structures made in this Smanner are illustrated in U.S. Patent 4,637,859 issued January 20, 1987 to
I(
2 Trokhan. Alternatively, a paper structure can be made stronger, without utilising more cellulosic fibers, by having regions of differing basis weights as illustrated in U.S. Patent 4,514,345 issued April 30, 1985.
Tissue paper manufacturers have also attempted to make tissue products more appealing to consumers by improving the aesthetic appearance of the product. For example, embossed patterns formed in tissue paper products after the tissue paper products have been dried are common.
One embossed pattern which appears in cellulosic paper towel products marketed by The Procter Gamble Company is illustrated in U.S. Patent Des.
239,137 issued March 9, 1976 to Appleman. Embossing is also illustrated in U.S. Patent 3,556,907 issued January 19, 1971 to Nystrand; U.S. Patent 3,867,225 issued February 18, 1975 to Nystrand; and U.S. Patent 3,414,459 issued December 3, 1968 to Wells.
However, embossing processes typically impart a particular aesthetic appearance to the paper structure at the expense of other properties of the structure. In particular, embossing a dried paper web disrupts bonds between fibers in the cellulosic structure. This disruption occurs because the bonds are formed and set upon drying of the embryonic fibrous slurry. After drying the paper structure, moving fibers normal to the plane of the paper structure by embossing breaks fiber to fiber bonds. Breaking bonds results in reduced tensile strength of the dried paper web. In addition, embossing is typically done after creping of the dried paper web from the drying drum. Embossing 0-0o after creping can disrupt the creping pattern imparted to the web. For instance, embossing can eliminate the creping pattern in some portions of the web by compacting or stretching the creping pattern. Such a result is •o undesirable because the creping pattern improves the softness and flexibility 0 of the dried web.
In addition, dry embossing a paper structure acts to stretch or draw the o paper structure around the perimeter of the embossments. As a result, the 30 paper structure around the perimeter of the embossments will have a reduced Sthickness relative to the non-embossed portion of the paper web.
3 Felts for use in papermaking are also well known. U.S. Pat. No.
3,537,954 issued to Justus discloses imparting a creping pattern to a web with a felt having yarns running in the cross machine direction along the outer surface of the felt. U.S. Pat. No. 4,309,246 issued to Hulit et al. discloses pressing a web between a felt and an imprinting fabric. U.S. Pat. No.
4,144,124 issued to Turunen et al. discloses a paper machine having a twinwire former having a pair of endless fabrics, which can be felts. One of the endless fabrics carries a paper web to a press section. The press section can include the endless fabric which carries the paper web to the press section, an additional endless fabric, and a wire for patterning the web. U.S. patent 5,328,565, Method of Pressing and Molding a Paper Sheet, filed December 1993 in the name of Ampulski et al. discloses a process for molding and dewatering a paper web which employs dewatering felts.
U.S. Patent 4,446,187 to Eklund discloses a sheet assembly which can be used as a forming fabric, press fabric, and drying fabric porous belt, including as a press felt and a drying felt. The sheet assembly includes a foil and a reinforcement structure bonded together. The foil can be formed from a plastic material, and is formed with through-holes. Eklund teaches that it is desirable to produce a belt fabric which possesses as even a surface as 20 possible to provide an even pressure distribution and to avoid a coarse surface structure in the finished paper. Eklund teaches that by adapting the diameter and positions of the holes in the foil, it is possible to obtain a dewatering belt possessing a very even pressure distribution.
U.S. Pat. No. 4,740,409 to Lefkowitz discloses a nonwoven fabric 25 having parallel machine direction yarns and interconnecting cross machine direction polymeric material surrounding the machine direction yarns. The i: l cross machine direction polymeric material contains spaced perforations through the fabric.
PCT Publication Number WO 92/17643 published October 15, 1992 in the name of Buchanan et al. and assigned to the SCAPA Group discloses a Sbase fabric for use in producing a papermakers fabric. The base fabric I (b 4 includes superimposed layers of thermoplastic materials in mesh form.
Buchanan teaches that the base fabric can be embodied in a marking felt.
PCT Publication Number WO 91/14558 published October 3, 1991 in the name of Sayers et al. and assigned to the SCAPA Group discloses a method of making an apertured polymeric resin material use in papermaking by curing a radiation curable polymeric material. Sayers et al. teaches that the apertured structure may be combined with a textile batt to form a papermakers dewatering felt. U.S. Patent 4,514,345 issued April 30, 1985 to Johnson et al.
teaches a method of making a foraminous member with a photosensitive resin.
PCT publication WO 95/17150, Tissue Paper Having Large Scale, Aesthetically Discernible Patterns and Apparatus for Making Same, filed June 19, 1991 in the name of Rasch et al. discloses a single lamina paper structure having at least three visually discernible regions. Rasch et al. teaches the three regions are visually distinguishable by an optically intensive property such as crepe frequency, elevation, or opacity. Rasch et al. teaches that opacity can be increased by increasing the density of a region. Rasch et al.
also teaches that differences in elevation between adjacent regions can be imparted to a paper structure by differences in elevation of the distal ends of S. 20 adjacent flow elements. While the structures of Rasch et al. provide an improvement over embossed paper structures, there is a need to provide tissue products having improved visually discernible patterns over those taught in Rasch et al. Therefore, those involved in the papermaking field continue to search for ways to make paper structures having highly discernible aesthetic patterns without sacrificing desirable paper web properties.
An object of the present invention is to provide a method of forming a *ilT I paper web, the method being an improvement or an alternative to the prior art.
:oo:SUMMARY OF THE INVENTION One aspect of the invention is an apparatus for use in making a web of 30 papermaking fibers, the apparatus including: I 30 papermaking fibers, the apparatus including: 4a a dewatering felt layer including a nonwoven batt of fibers, the felt layer having a first web facing felt surface at a first elevation and an oppositely facing second felt surface; and a web patterning layer joined to the first web facing surface of the dewatering felt layer, wherein the web patterning layer extends from the first felt surface, the patterning layer having a continuous network web contacting top surface at a second elevation different from the first elevation, the continuous network top surface having a plurality of discrete openings therein, wherein the surface area of the continuous network top surface is between 5 percent and percent of the projected area of the apparatus, and wherein the continuous netwbrk top surface has less than 700 discrete openings therein per square inch of projected area of the apparatus.
The difference between the first elevation and the second elevation is preferably between about 0.05 and about 2.0 millimeter. The web patterning layer can comprise a photosensitive resin cured on the dewatering felt layer to penetrate the first web facing surface. The web patterning layer can extend through less than the full thickness of the dewatering felt layer.
In one embodiment the web patterning layer has a continuous network woo* 20 web contacting top surface having a plurality of discrete openings therein.
The continuous network web contacting surface can have a projected surface area of between 20 percent and about 60 percent of the projected area of the apparatus, less than about 700 discrete openings per square inch of the projected area of the apparatus, and preferably between about 70 and about eo.l 25 700 discrete openings therein per square inch of the projected area of the *c apparatus. Such a web patterning layer is suitable for forming a paper l structure having a continuous, relatively high density network region and a plurality of relatively low density domes dispersed throughout the network region.
In another embodiment the first felt surface can be deflected relative to the web contacting top surface of the web patterning layer under a prescribed loading to reduce, and preferably substantially eliminate, the difference between the first and second elevations. The web contacting surface of the web patterning layer has a projected surface of area of between about percent and about 20 percent, and more preferably between about 5 and about 14 percent of the projected area of the apparatus. The web patterning layer inscribes a plurality of circular portions of the first felt surface, each inscribed circular portion having a projected area of at least about 10 square millimeters, more preferably at least about 20 square millimeters, and most preferably at least about 100 square millimeters. A web support apparatus having such a dewatering felt layer and web patterning layer is suitable for making a paper structure having a transition region interconnecting first and second regions disposed at different elevations, wherein the transition region thickness is greater than the thickness of the second region, and greater than or equal to the thickness of the first region. Such a web support apparatus is also suitable for making a paper structure having large scale, visually discernible patterns with foreshortened regions at different elevations.
Another aspect of the invention is a paper structure including: 20 a first region disposed at a first elevation and having a first thickness; a second region disposed at a second elevation different from the first .*elevation and having a second thickness; and ooa third transition region interconnecting the first region and the second region, the third region having a third thickness, the third thickness greater 25 than the second thickness, and the third thickness greater than the first thickness.
The first and second regions can be foreshortened, such as by creping, and the difference in elevation between the first and second foreshortened regions can be at least about 0.05 millimeter. In one embodiment of the present invention, a variable frequency creping region extends from at least a portion of the border of a patterned second region and terminates in a first region, thereby enhancing the visual discernibility of the second region.
Another aspect of the invention is a paper structure including: a first region; a second patterned region; a transition region interconnecting the first region and the second region; and a variable creping frequency region; the variable creping frequency region bordering at least a portion of the second patterned region; and the variable creping frequency region extending from a border of the patterned second region and terminating in the first region.
Another aspect of the invention, being the subject matter of the claims of this application is a method for forming a paper web. The method includes the steps of: providing a generally uncompacted, generally monoplanar wet web of paper making fibers; deflecting the web at a consistency of between 8 and 30 percent in a first deflection step to provide a non-monoplanar web having a first region at a first elevation and a second region at a second elevation different from the first elevation; deflecting the first region to the second region in a second deflection step to reduce the difference in elevation between the first web region and the second web region in a second deflection step at a web consistency of 25 between 20 and 80 percent; compacting at least a portion of the first web region at a consistency of between 20 and 80 percent to provide a first compacted web region; compacting at least a portion of the second web region at a consistency i of between 20 and 80 percent to provide a second compacted web region; 30 and 30 and 0 (b.
7 restoring at least some of the difference in elevation between the first web region and the second web region to provide a first compacted web region disposed at a first elevation and a second compacted web region disposed at a second elevation different from the first elevation.
DESCRIPTION OF THE DRAWINGS While the Specification concludes with claims particularly pointing out and distinctly claiming the desired aspect of the present invention, the invention will be better understood from the following description of exemplary embodiments taken in conjunction with the associated drawings, in which like elements are designated by the same reference numeral, and: Figure 1 is a plan view illustration of an embodiment of an apparatus for use in papermaking, the apparatus comprising a dewatering felt layer and a web patterning layer joined to the dewatering felt layer and having a continuous network web contacting top surface.
Figure 2 is a cross-sectional view of the apparatus of Figure 1 showing the dewatering felt layer to have a first web facing felt surface at a first elevation and an oppositely facing second felt surface, and showing the web patterning layer penetrating the first felt surface to extend through less than the full thickness of the dewatering felt layer, the web patterning layer 20 extending from the first felt surface to form the web contacting top surface at a second elevation different from the first elevation.
Figure 3 is a plan view illustration of an alternative embodiment of an apparatus for use in papermaking, the apparatus comprising a dewatering felt layer having a first web facing felt surface, and a web patterning layer 25 penetrating the first felt surface, the web patterning layer extending from the e*e° S. first felt surface and having a discontinuous web contacting top surface.
f Figure 4 is a photographic plan view of an embodiment of an apparatus for use in papermaking comprising a dewatering felt layer having a first web facing felt surface and a web patterning layer penetrating the first felt surface, S" 30 the web patterning layer comprising a plurality of discrete web patterning ,elements.
I, (N.
8 Figure 5 is a cross-sectional illustration of a paper structure according to an embodiment of the present invention, the paper structure having a transition region interconnecting first and second regions disposed at different elevations, wherein the transition region thickness is greater than the thickness of the second region, and greater than or equal to the thickness of the first region.
Figure 6A is a photomicrograph of a cross-section of a paper structure according to an embodiment of the present invention.
Figure 6B is the photomicrograph of 6A showing elevation reference lines.
Figure 7 is a photographic plan view of a paper structure according to the present embodiment.
Figure 8 is a photographic plan view of paper structure according to the present embodiment, enlarged relative to Figure 7, and showing a variable creping frequency region.
Figure 9 is an illustration of a process for making a paper structure according to the present embodiment.
Figure 10 is an illustration of a non-monoplanar, generally uncompacted paper web deflected while supported on a web support 20 apparatus comprising a felt layer and a web patterning layer to provide a first generally uncompacted web region at a first elevation and a second generally uncompacted web region at a second elevation different from the first oo. elevation.
Figure 11 is an illustration of a paper web being compacted against the *gO B 25 surface of a drying drum by deflecting the first felt surface of the web support apparatus relative to the web contacting surface of the web patterning layer.
Figure 12 is an illustration of a machine for making a web support apparatus having a felt dewatering layer and a web patterning layer formed from photosensitive resin.
LI 8a Figure 13 is a plan view illustration of a web support apparatus wherein the web patterning layer comprises a lattice network and a plurality of discrete web patterning elements disposed within openings in the lattice network.
Figure 14 is a plan view illustration of a paper structure made with the apparatus of Figure 13.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION The embodiments include examples of the claimed and non-claimed aspects of the invention.
Figures 1-4 and 13 illustrate embodiments of a web support apparatus 200 for use in making a web of papermaking fibers, the apparatus comprising a dewatering felt layer 220 and a web patterning layer 250. Figures 5-8 and 14 illustrate an embodiment of a paper structure 20 according to an embodiment of the present invention, the paper structure having a transition region interconnecting first and second regions disposed at different elevations, wherein the transition region thickness is greater than the thickness of the second region, and greater than or equal to the thickness of the first region. Figures 9-11 illustrate an embodiment of a method of the presently claimed aspect of the invention, the embodiment of the method .employing an apparatus 200 such as that shown in Figure 4 for making a 20 paper structure 20. Figure 12 is a schematic illustration of a non-claimed method for making a web support apparatus 200 having a web 9* 0SO patterning layer 250 formed of photosensitive resin cured on a dewatering felt laver 220.
Web Support Apparatus Figures 1, 2. 3. and 4 show different embodiments of a web support apparatus 200. which can comprise a continuous drying belt (Figure 9) for drying and imparting a pattern to a paper web. The web support apparatus 200 has a first web facing side 202 and a second oppositely facing side 204. The web support apparatus 200 is viewed with the first web facing side 202 toward the viewer in Figures 1.3.
and 4.
The web support apparatus 200 comprises a dewatering felt layer 220 having a first web facing felt surface 230 disposed at a first elevation 231. and an oppositely facing second felt surface 232. The web support apparatus 200 also comprises a web patterning layer 250 joined to the first web facing surface 230. The web patterning layer 250 extends from the first felt surface 230, as shown in Figure 2, to 20 have a web contacting top surface 260 at a second elevation 261 different from the first elevation 231. The difference 262 between the first elevation 231 and the second elevation 261 is at least about 0.05 millimeter, and is preferably between about 0.1 and about 2.0 millimeters.
The dewatering felt layer 220 is water permeable and is capable of receiving 25 and containing water pressed from a wet web of papermaking fibers. The web patterning layer 250 is water impervious, and does not receive or contain water pressed from a web of papermaking fibers. The web patterning layer 250 can be continuous, as shown in Figure 1, or discontinuous, as shown in Figures 3 and 4.
The web patterning layer 250 preferably comprises a photosensitive resin which can be deposited on the first surface 230 as a liquid and subsequently cured by radiation so that a portion of the web patterning layer 250 penetrates, and is thereby securely bonded to. the first felt surface 230. The web patterning layer 250 preferably does not extend through the entire thickness of the felt layer 220, but instead extends through less than about half the thickness of the felt layer 220 to maintain the flexibility and compressibility of the web support apparatus 200, and particularly the flexibility and compressibility of the felt layer 220. The curing depth can be controlled by a number of different methods, alone or in combination, such as by varying the intensity and duration of the actinic radiation; varying the thickness of the felt layer 220. The photosensitive resin under the first felt surface 230 can then be cured so that the web patterning layer 250 penetrates the first felt surface but does not extend through the full thickness of the felt layer. The web patterning layer 250 is thereby securely bonded to the felt layer 220 while maintaining flexibility of the felt layer 220 and the web support apparatus 200.
A suitable dewatering felt layer 220 comprises a batt 240 of natural or synthetic fibers joined, such as by needling, to a support structure formed of woven filaments 244. Suitable materials from which the batt 240 is formed include but are not limited to natural fibers such as wool and synthetic fibers such as polyester and nylon. The fibers from which the batt 240 is formed can have a denier of between about 3 and 20 grams per 9000 meters of filament length.
The felt layer 220 can have a layered construction, and can comprise a mixture of fiber types and sizes. The felt layer 220 is formed to promote transport of water received from the web away from the first felt surface 230 and toward the second felt surface 232. The felt layer 220 can have finer, relatively densely packed fibers disposed adjacent the first felt surface 230. The felt layer 220 preferably has a relatively high density and relatively small pore size adjacent the first felt surface 230 as compared to the density and pore size of the felt layer 220 adjacent the second felt 20 surface 232, such that water entering the first surface 230 is carried away from the first surface 230.
The dewatering felt layer 220 can have a thickness of between about 2 millimeters and about 5 millimeters, a basis weight of between about 800 and about 2000 grams per square meter, an average density (basis weight divided by thickness) 25 of between about 0.35 gram per cubic centimeter and about 0.45 gram per cubic centimeter, and an air permeability of between about 5-50 standard cubic feet per minute (scfm), where the air permeability in scfin is a measure of the number of cubic feet of air per minute that pass through a one square foot area of the felt layer 220 at a pressure drop across the thickness of the felt layer 220 equal to about 0.5 inch of water. The air permeability is measured using a Valmet permeability measuring device (Model Wigo Taifun Type 1000) available from the Valmet Corp. of Pansio, Finland. The permeability of the web support apparatus 200 is less than or equal to the permeability of the felt layer 220 and is about equal to the permeability of the felt layer 220 multiplied by the fraction of the projected area of the apparatus 200 not covered by the web patterning layer 250.
A suitable felt layer 220 is an Amflex 2 Press Felt manufactured by the Appleton Mills Company of Appleton, Wisconsin. Such a felt layer 220 can have a thickness of about 3 millimeter, a basis weight of about 1400 gm/square meter, an air permeability of about 30 scfm, and have a double layer support structure having a 3 ply multifilament top and bottom warp and a 4 ply cabled monofilament crossmachine direction weave. The batt 240 can comprise polyester fibers having a denier of about 3 at the first surface 230. and denier of between about 10-15 in the batt substrate underlying the first surface 230.
The web patterning layer 250 is preferably made by applying a layer of liquid photosensitive resin to the first felt surface 230. exposing at least some of the liquid photosensitive resin to a source of actinic radiation, curing some of the resin to provide a solid resin web patterning layer 250 having a predetermined pattern, and removing the uncured resin from the dewatering felt layer 220. Photosensitive resins are materials, such as polymers, which cure or cross-link under the influence of actinic radiation, usually ultraviolet (UV) light. Suitable resins are disclosed in U.S.
Patent 4.514,345 issued April 30 1985 to Johnson et al. which patent is incorporated herein by reference.
The resin, when cured, should have a hardness of no more than about 60 Shore D. The hardness is measured on an unpatterned photopolymer resin coupon measuring about 1 inch by 2 inches by 0.025 inches thick cured under the same conditions as the web patterning layer 250. The hardness measurement is made at 20 85 degrees Centigrade and read 10 seconds after initial engagement of the Shore D durometer probe with the resin. A resin having such a hardness upon curing is desirable so that the web patterning layer 250 is somewhat flexible and deformable.
Flexibility and deformability of the web patterning layer 250 can be desirable for making the paper structure 20 described below.
25 The resin preferably resists oxidation, and can have viscosity of between about 5000 and about 15000 centipoise at 70 degrees Fahrenheit to facilitate penetration of felt layer 220 by the resin prior to curing. Suitable liquid photosensitive resins are included in the Merigraph series of resins made by Hercules Incorporated of Wilmington, Delaware incorporating an antioxidant to improve the life of the web patterning layer 250.
The web support apparatus 200 can be made using the process schematically illustrated in Figure 12. In Figure 12, a forming unit 1513 in the form of a drum is provided having a working surface 1512. The forming unit 1513 is rotated by a drive means not illustrated. A backing film 1503 is provided from a roll 1531, and taken up by a rol 1532. Intermediate the rolls 1531 and 1532, the backing film 1503 is applied to the working surface 1512 of the forming unit 1513. The function of the backing film is to protect the working surface of the forming unit 1513 and to facilitate the removal of the partially completed web support apparatus 200 from the forming unit 1513. The backing film 1503 can be made of any suitable material including but not limited to, polypropylene and have a thickness of between about 0.01 and about 0. 1 millimeter.
The felt dewatering layer 2210. which is shown in the form of a Continuous'belt in Figure 12, is conveyed across a precoating nozzle 1420 positioned agzainst the first felt surface 2-30. The nozzle 1420 extrudes a film 1402 of the liquid photosensitive resin onto the first felt surface 23)0 to uniformly cover the first felt surface. The extruded film 1402 wets the surface 230 and helps prevent the formation of air bubbles on the first felt surface 230 when additional resin is subsequently applied to the first felt surface 230.
The felt dewatering layer 220 is then positioned adjacent the backing film 1503 such that backing film 1503 is interposed between the felt dewatering layer 220 and the forming unit 1513, and such that the second felt surface 232 of the felt dewatering layer 220 is positioned adjacent the backing film 1503. As shown in Figure 12. the felt dewatering layer 220 in the form of a continuous belt is conveyed about return roll 1511, about forming unit 1513, and around return rolls 1514 and 1515.
A coating of liquid photosensitive resin 1502 is applied over the film 1402.
The coating of liquid photosensitive resin 1502 can be applied to the first felt surface in any suitable manner. In Figure 12 the coating of resin 1502 is applied by a nozzle 1520. The thickness of the coating of resin 1502 is controlled to a preselected value corresponding to the desired difference in elevation 262 between the elevation 23 1 of the, first felt surface 230 and the elevation 261 of the web contacting top surface ~25 260 of the web patterning layer 250. In Figure 12, the thickness of the coating of resin 1502 is controlled by mechanically controlling the clearance between a nip roll 1541 and the forming unit 1513. The nip roll 1541 in conjunction with amask 1504 *and a mask guide roll 1542 tend to smooth the surface of the resin 1502 and control its thickness, and distribute the liquid resin through the entire thickness of the felt layer 220.
~thThe mask 1504 can be formed of any suitable material which can be provided *wt opaque and trasparent portions. The transparent portions are arranged in a pattern corresponding to the desired pattern of the web patterning layer 250. A material in the nature of a flexible photographic film is suitable. The opaque portions can be applied to the mask 1504 in any suitable way, such as photographic, gravure.
flexographic, or rotary screen printing. The mask 1504 can be an endless belt. or alternatively, supplied from one supply roll and taken up by a take-up roll. As shown in Figure 12, the mask 1504 is conveyed around the rolls 1541 and 1542, and intermediate the rolls 1541 and 1542 is brought into contact with the surface of the resin 1 502- The photosensitive resin 1502 is exposed. to actinic radiation of an activating wavelength through the mask 1504. thereby inducing partial curing of the resin 1502 in those portions of the layer of resin 1502 which are in register with transparent portions of the mask 1504 to form a partially cured resin layer 1521. In Figure 12 radiation having an activating wavelength is supplied by a first exposure lamp 1505.
The activating wavelength is a characteristic of the resin 1502. and can be supplied by any suitable source of illumination such as mercury arc, pulsed xenon, electrodless. and fluorescent lamps. Partial curing of the resin is manifested by a solidification of the resin registered with the transparent portions of the mask 1504.
while the unexposed portions of the resin 1502 registered with the opaque portions of the mask 1504 remain liquid.
A subsequent step in forming the apparatus 200 comprises removing substantially all the uncured liquid resin from the felt dewatering layer 220. The uncured liquid resin can be removed from the felt layer 220 by washing the felt layer 220 in a mixture of surfactant and water. At a point adjacent the roll 1542 the mask 20 1504 and the backing film 1503 are separated from the felt layer 220 and the partially cured resin layer 1521. The composite felt layer 220 and partially cured resin layer 1521 travel to a first resin removal vacuum shoe 1523, where a vacuum is applied to the second felt surface 232 to remove uncured resin. The composite felt layer 220 and partially cured resin layer 1521 then travel past top wash showers 25 1524A and bottom wash showers 1524B. The showers 1524A, B deliver a washing mixture of water and a surfactant in a concentration of between about 0.01 and about 0.1 percent by volume surfactant. A suitable surfactant is a TOP JOB® brand detergent manufactured by The Procter and Gamble Company of Cincinnati, Ohio.
The showers 1524A, B deliver the washing mixture at a temperature of about 160 degrees using fan jet nozzles such as Spray Systems nozzles number SS2506 having an orifice diameter of about 0.062 inches. The shower delivery pressure is about 140 psi at the top showers 1524A, and about 100 psi at the bottom showers 1524B. The showers 1524A, B and the felt layer 220 can be moved laterally relative to one another to eliminate streaking and provide uniform removal of the liquid resin across the width of the felt layer 220.
The composite felt layer 220 and resin layer 1521 then travel over a vacuum shoe 1600 where a vacuum is applied to the second felt surface 232 to remove uncured liquid resin and the washing mixture. The composite felt layer 220 and resin layer 1521 are then carried through a bath 1620 of water. A post cure lamp 1605 positioned over the bath 1600 is turned off while the composite felt layer 220 and resin layer 1521 are carried through the bath 1600. After leaving the bath 1600. a vacuum is applied to the second felt surface 232 by a vacuum shoe 1626 to remove uncured liquid resin and the water from the felt The washing sequence of carrying the felt layer 220 past the vacuum shoe 1523: washing the felt layer with the washing mixture at the showers 1524A, B.
carrying the felt layer 220 past the vacuum shoe 1600; carrying the felt layer 220 through the bath 1600 comprising water: and carrying the felt layer 220 past the vacuum shoe 1626 is repeated at least about 4 to 6 times until substantially all the uncured liquid resin is removed from the felt layer 220. The washing sequence can be repeated by carrying the composite felt layer 220 and resin layer 1521 around the circuit provided by the rollers 15 14. 15 15. 1511, and 1513 four to six times. The first curing lamp 1505 and the post cure lamp 1605 are turned off during each repetition of the washing sequence.
Once the uncured liquid resin has been removed from the felt layer 220, the felt layer 220 is rinsed with water to remove wash mixture from the felt layer 220. After the residual wash mixture is removed from the felt layer, curing of the partially cured resin layer 1521 is completed with the post curing lamp 1605.
To remove the wash mixture from the felt layer 220, the composite felt layer *220 and resin layer 1521 are first carried past the vacuum shoe 1523 to remove wash mixture. The composite felt layer 220 and resin layer 1521 are then carried through the showers 1524A, B and a second rinse shower 1525 which rinse the felt layer 220 with water only in order to remove any excess wash mixture. To complete curing of the resin layer 152 1, the composite felt layer 220 and resin layer 1521 are submerged in the bath 1620 which has been previously emptied and refilled to contain only *.:water. The composite felt layer 220 and resin layer 1521 are carried through the bath 1620 with the post curing lamp 1605 turned on. The water in the bath 1620 permiuts passage of the actinic radiation from the post curing lamp 1605 to the resin ~:layer 1521, while precluding oxygen which can quench the free radical *.:polymerization reaction. Just prior to and during the post curing operation, the water sprayed from the showers 1524A, B and 1525 and the water in the bath 1620 should not include the surfactant because presoence of the surfactant can restrict passage of the actinic radiation through the bath 1620 and to the resin layer 152 1.
After exiting the bath 1620, the composite felt layer 220 and resin layer 1521 are carried over the vacuum shoe 1526 to remove water from the felt layer 220.
The post curing sequence of passing the composite felt layer 220 and resin layer 1521 over the vacuum shoe 1523; through the showers 1524Ak B and 1525: through the bath 600 with the post curing lamp 1605 turned on, and over the vacuum shoe 1626 can be repeated about I to 3 times until the resin layer 1521 is no longer tacky. At this point. the felt' layer 220 and the cured resin, together, form the web support apparatus 200 having a web patterning layer 250 formed Of the cured resin. The post curing sequence can be repeated by carrying the composite felt layer 220 and resin layer 1521 around the circuit provided by the rollers 15 14. 15 1511, and 15 13 one to three times with the lamp 1505 turned off.
In one embodiment, the mask 1504 can be provided with a transparent portion in the form a continuous network. Such a mask can be used to provide the web support apparatus 200 having a web patterning layer 250 having a continuous network web contacting top surface 260 having a plurality of discrete openings 270 therein, as shown in Figure 1. Each discrete opening 270 communicates with the first felt surface 230 through a conduit formed in the web patterning layer 250.
Suitable shapes for the openings 270 include, but are not limited to circles, ovals elongated in the machine direction (NM in Figure polygons, irregular shapes, or mixtures of these. The projected surface area of.the continuous network top surface 260 can be between about 5 and about 75 percent of the projected area of the web support apparatus 200 as viewed in Figure 1, and is preferably between about percent and about 60 percent of the projected area of the web support apparatus 200 *as viewed in Figure 1.
In the embodiment shown in Figure 1, the continuous network top surface 260 can have less than about 700 discrete openings 270 per square inch of the projected area of the web support apparatus 200, and preferably between about 70 and about 700 discrete openings 270 therein per square inch of projected area of the web support apparatus as viewed in Figure 1. Each discrete opening 270 in the **:continuous network top surface can have an effective free span which is between about 0.5 and about 3.5 mnilimeter, where the effectv free sa sdfnda h area of the opening 270 divided by one-fourth of the perimeter of the opening 270.
The effective free span can be between about 0.6 and about 6.6 times the elevation difference 262. An apparatus having such a pattern of openings 270 can be used as a drying belt or press fabric on a papermaking machine for makcing a patterned paper structure having a continuous network region which can be a compacted, relatively high density region corresponding to the web contacting surface 260, and a plurality of generally uncompacted domes dispersed domes dispersed throughout the continuous network region, the domes corresponding to the positioning of the openings 270 in the surface 260. The discrete openings 270 are preferably bilaterally staggered in the machine direction (MD) and cross-machine direction (CD) as described in U.S. Patent 4,637,859 issued January 20, 1987, which patent is incorporated herein by reference. In the embodiment shown in Figure 1, openings 16 270 are over-lapping and bilaterally staggered, with the openings sized and spaced such that in both the machine and cross-machine directions the edges of the openings 270 extend past one another, and such that any line drawn parallel to either the machine or cross-machine direction will pass through at least some openings 270.
In the embodiment shown in Figure 3. the web patterning layer 250 has a discontinuous web contacting top surface 260. The web patterning layer 250 comprises a plurality of discrete projections 275. The projections 275 can have any suitable shape, including but not limited to circles, ovals, polygons, irregular shapes, and mixtures of these. The apparatus 200 can have between about 50 and about 500 projections 275 per square inch of projected area of the apparatus 200, with each projection 275 surrounded by the first felt surface 230. The surface area of the top surface 260 can be between about 20 and about 60 percent of the projected area of the apparatus 200 as viewed in Figure 3, and each projection 275 can have a maximum width of between about 0.6 and about 3.0 millimeter, with the maximum spacing between adjacent projections 275 no greater than about 2.0 millimeter. An 0 20 apparatus 200 having such an arrangement of projections 275 can be used as a drying belt or press fabric on a papermaking machine to make a patterned paper .structure having discrete compacted regions corresponding to the discrete surfaces 260 of each projection 275. In such a structure, the discrete compacted regions, which can be relatively high density regions, are dispersed throughout a continuous 25 relatively uncompacted network, which network can be a relatively low density network region. Optionally, each discrete projection 275 can include a conduit 277 extending through the projection 275, the conduit bounded by the first felt surface 230.
In another embodiment, the web contacting top surface 260 has a projected surface area of between about 5 and about 20 percent, and more preferably between about 5 and about 14 percent of the projected area of the web support apparatus 200. The web patterning layer 250 inscribes a plurality of circular portions of the first felt surface 230, each inscribed circular portion having a projected area of at least about 10, preferably about 20, and more preferably at least about 100 square millimeters.
A web support apparatus 200 having a web contacting top surface 260 with a projected area in the above range and inscribing relatively large portions of the first felt surface 230, as described above, can be used to make a paper structure having a transition region interconnecting first and second regions disposed at different elevations, wherein the transition region thickness is greater than the thickness of the second region. and greater than or.equal to the thickness of the first region.
In the embodiment shown in Figure 4. the web patterning layer 250 comprises a plurality of discrete web patterning elements 280 joined to the felt layer 220. Each discrete web patterning element 280 extends from the first felt surface 230 to have a discrete web contacting top surface 260. The spacing (DA in Figure 4) between at least some adjacent elements 280 can be at least about 8 millimeter, and preferably at least about 10 times the difference between the first elevation 23 I of the first felt surface 230 and the second elevation 261 of the web contacting top surface 260. Elements 280 are considered to be adjacent if the shortest straight line which can be drawn between the two elements does not intersect a third element.
Referring to Figure 4, at least some adjacent web patterning elements 280 preferably can inscribe a plurality of circular portions CA of the first felt surface 230 having a projected surface area of at least about 10, preferably about 20 and more preferably about 100 square millimeters. In the embodiment shown in Figure 4, a 20 plurality of the discrete web patterning elements 280 are surrounded by the first felt surface 230. A plurality of the web patterning elements 280 each enclose a discrete opening 285. Each discrete enclosed opening 285 communicates with a surface having an elevation different from the surface 260. Preferably, each enclosed opening 285 communicates with the first felt surface 230. Some of the discrete web 25 patterning elements 280 shown in Figure 4 comprise flower shaped patterning :elements.
The belt apparatus 200 having a web patterning layer 250 with the above projected area and disposed to inscribe portions of the first felt surface 230 with the above area is relatively flexible compared to a belt made from the same underlying felt layer but having a larger percentage of its surface covered by a web patterning layer. Such flexibility is one factor which permits deflection of the first felt surface 230 relative to the web contacting top surface 260 of the web patterning layer 250 for formation of a paper structure 20 having foreshortened regions at different elevations, as described below.
Figure 13 shows an alternative embodiment of a web support apparatus 200.
Figure 13 is a plan view illustration of a web support apparatus 200 wherein the web patterning layer 250 comprises a lattice network 290 and a plurality of discrete web patterning elements 280 disposed within at least some of a plurality of cells 292 formed by the lattice network 290. The lattice 290 in Figure 13 comprises spaced apart bands 294 which intersect spaced apart bands 296 to form the cells 292. The bands 294 and/or the bands 296 can be unbroken, or alternatively, can be formed by 18 a plurality of short, spaced apart segments. In Figure 13 the bands 294 are unbroken and extend generally in the machine direction, and the bands 296 are unbroken and extend generally in the cross-machine direction. The web patterning layer 250 has a web contacting top surface 260 which comprises a continuous network web contacting top surface formed by the intersecting bands 294 and 296, and a discontinuous web contacting top surface formed by the discrete elements 280.
PAPER STRUCTURE A paper structure according to the present invention is taken off the web support apparatus 200 as a single ply having one or more fiber constituent layers. Though not necessary, two or more paper structures of the present embodiment can be joined together after drying to form a multi-ply paper product. A "zone" as used herein refers to a contiguous portion of the paper structure. A "region" of a paper structure, as used herein, refers to a portion or portions of the paper structure having a common property or characteristic, such as density, thickness, elevation, or creping pattern.
A
region can comprise one or more zones, and can be continuous or discontinuous.
Referring to Figures 5-8, the paper structure 20 according to the 20 present embodiment comprises a tissue paper web having a first S-nonembossed region 30 disposed at a first elevation 32 and having a first thickness 31; a second nonembossed patterned region 50 disposed at a second elevation 52 different from the first elevation 32, and having a second thickness 51; and a third transition region 70 interconnecting the first and e 25 second nonembossed regions 30 and 50. The transition region 70 has a thickness 71. In a non-claimed aspect of the invention, the thickness 71 is greater than the second thickness 51, and the thickness 71 is greater than or equal to the first thickness 31. In the embodiment shown in Figures 5 and 6A, B the thickness 71 is greater than each of the thicknesses 31 and 51. The thickness 71 is preferably at least 1.5 times greater than each of the thicknesses 31 and 51.
18a The difference between the first and second elevations 32 and 52 is designated 62 in Figure 5. The difference 62 is preferably at least about 0.05 millimeter. Such a difference in elevation is desirable to enhance the visual distinctness of the first and second regions 30 and 50. The thicknesses 31, 51 and 71 and the elevation difference 62 can be measured using the procedure described below with reference to Figures 6A and 6B.
The first and second regions 30 and 50 can be formed by selectively deflecting and compacting a wet web of papermaking fibers, as described below. For a web having a generally constant basis weight having thicknesses 31 and 51 less 0000 0 0 0 a a ee...
a a 0 a 0 :-.00 0.00 9:.00 00.0 0 00 than the thickness 71. the first and second regions 30 and 50 can be characterized as relatively high density regions, while the transition region 70 can be a relatively low density region.
The first and second regions 30 and 50 are foreshortened. Foreshortening can be provided by creping a paper web with a doctor blade, as described below.
Foreshortened portions of the paper structure 20 are characterized by having a creping pattern having a creping frequency. The creping pattern of the first region is indicated by reference numeral 35, and is characterized by a series of peaks and valleys extending generally in the cross-machine direction. The machine and crossmachine direction are indicated as MD and CD, respectively, in the Figures. The creping pattern of the second region 50 is indicated by reference numeral 55 and is characterized by a series of peaks and valleys. The creping frequency of a creping pattern is defined as the number of times a peak occurs on the surface of the paper structure for a given linear distance measured in the machine direction.
The first and second regions 30 and 50 have foreshortened portions disposed 20 at different elevations, such that at least a portion of the creping pattern 35 is disposed at an elevation different from the elevation at which the creping pattern is disposed. At least a portion of the patterned second region 50 can be bordered by an uncreped zone, or a zone having a creping frequency different from that of the second region 50. In Figure 5 the transition region 70 interconnecting the second 25 region 50 with the first region 30 can be uncreped. or have a creping frequency different from that of the second region Referring to Figures 7 and 8, at least a portion of the patterned second region 50 can be bordered by a variable frequency creping region. The variable frequency creping region has a reduced creping frequency relative to the creping frequency of at least one of the'creping patterns 35 and 55. The variable frequency creping region is visible in Figures 7 and 8 as wrinkles 92 extending in the cross-machine direction.
The wrinkles 92 of the variable frequency creping region extend from a portion of the border of the second region 50, and terminate in the first region 30. The creping patterns 35 and 55 can have frequencies of at least about 1.5 times that of the frequency of the wrinkles 92.
The wrinkles 92 and the transition region 70 border a portion of second region and thereby help to visually offset the second region 50 from the first region Referring to Figures 7 and 8, the second region 50 can comprise a plurality of discrete zones 54 (a single discrete zone 54 is shown in Figure where each discrete zone 54 corresponds to a web patterning element 280 such as those shown in Figure 4. The first region 30 can comprise a continuous network, with a plurality 0J f( of discrete zones 54 surrounded by the first region 30. Each discrete zone 54 is interconnected with the first region 30 by the transition region 70, discrete portions of which can encircle the discrete zones 54.
Adjacent discrete zones 54 can inscribe a plurality of circular zones
C
of the first region 30. One inscribed zone C is shown in Figure 7. The projected area of some inscribed circular zones C are at least about preferably about 20 and more preferably at least about 100 square millimeter.
The spacing D between at least some adjacent discrete zones 54 of the second region 50 can be at least about 8 millimeters, and preferably at least about 10 times greater than the difference 62 between the first elevation 32 and the second elevation 52.
Referring to Figures 7 and 8, a plurality of the discrete zones 54 can enclose one or more discrete zones 130 corresponding to the openings 285 in a web patterning element 280. Each discrete, enclosed zone 130 can have an elevation 131 different from the second elevation 51 of the second region Each of the enclosed zones 130 can have a creping pattern 135, as shown in Figures 5 and 8.
Figure 14 illustrates an alternative embodiment of a paper structure As shown in Figure 14, the second region 50 can comprise a lattice network 20 1050 defining cells 1052, and a plurality of discrete zones 54. The discrete zones 54 can be disposed within at least some of the cells 1052 of the lattice network 1050.
The lattice network 1050 shown in Figure 14 comprises spaced apart bands 1054 which intersect spaced apart bands 1056 to form the cells 1052.
25 The bands 1054 and/or the bands 1056 can be unbroken, or alternatively, can be formed by a plurality of short, spaced apart segments. In Figure 14 the bands 1054 and 1056 are unbroken. The bands 1054 extend generally in the machine direction, and the bands 1056 extend generally in the cross-machine direction. The intersecting, unbroken bands 1054 and 1056 thereby form a continuous network lattice 1050.
9
S
S S 5 S
S
S
C
C
S. C 9 The paper structure 20 according to the present embodiment preferably has a basis weight of between about 7 pounds per 3000 square feet (about 11 gram/square meter) and about 35 pounds per 3000 square feet (57 gram/square meter), which basis weight range is desirable for providing paper structures 20 suitable for use in bath tissue and facial tissue products. The basis weight of the paper structure 20 is measured by cutting eight single ply samples of the paper structure 20 conditioned at 73 degrees Fahrenheit and percent relative humidity, each sample measuring 4 inches by 4 inches (0.0103 square meter). The eight 4 inch by 4 inch samples are placed one on top of each other and weighed to the nearest 0.0001 gram. The basis weight of the eight samples (in grams/square meter) is the combined weight of the eight samples in grams divided by the sample area of 0.0103 square meter.
The basis weight of the paper structure 20 is obtained by dividing the combined basis weight of eight samples by eight.
PAPERMAKING METHOD
DESCRIPTION
A paper structure 20 according to other aspects of the present invention can be made with the papermaking apparatus shown in Figures 9-11.
Referring to Figure 9, the method of making the paper structure 20 according to an exemplary embodiment of the presently claimed aspect of the present 20 invention is initiated by depositing a slurry of papermaking fibers from a headbox 500 onto a foraminous, liquid pervious forming member, such as a forming belt 542, followed by forming an embryonic web of papermaking fibers 543 supported by the forming belt 542. The forming belt 542 can comprise a continuous Fourdrinier wire, or alternatively, can be in the form of any of the 25 various twin wire formers known in the art.
It is anticipated that wood pulp in all its varieties will normally comprise the paper making fibers used in this embodiment. However, other cellulose fibrous pulps, such as cotton liners, bagasse, rayon, etc., can be used and none are disclaimed. Wood pulps useful herein include chemical pulps such as Kraft, sulfite and sulfate pulps as well as mechanical pulps including for Sexample, ground wood, thermomechanical pulps and Chemi-
U
r. 4 4 a 0 4 4 4 4444 4.
4 44 ThermoMechanical Pulp (CTMP). Pulps derived from both deciduous and coniferous trees can be used.
Both hardwood pulps and softwood pulps as well as blends of the two may be employed. The terms hardwood pulps as used herein refers to fibrous pulp derived from the woody substance of deciduous trees (angiosperms): wherein softwood pulps are fibrous pulps derived from the woody substance of coniferous trees (gymnosperms). Hardwood pulps such as eucalyptus having an average fiber length of about 1.00 millimeter are particularly suitable for tissue webs described hereinafter where softness is important, whereas northern softwood Kraft pulps having an average fiber length of about millimeter are preferred where strength is required. Also applicable to the present embodiment are fibers derived from recycled paper, which may contain any or all of the above categories as well as other non-fibrous materials such as fillers and adhesives used to facilitate the original paper making.
The paper furnish can comprise a variety of additives, including but not limited to fiber binder materials, such as wet strength binder materials, dry strength binder materials, and chemical softening compositions. Suitable wet strength binders include, but are not limited to, materials such as polyamide- 20 epichlorohydrin resins sold under the trade name of Kymene® 557H by Hercules Inc., Wilmington, Del. Suitable temporary wet strength binders include but are not limited to modified starch binders such as National Starch 78-0080 marketed by National Starch Chemical Corporation, New York, N.Y.
Suitable dry strength binders include materials such as carboxymethyl cellulose and cationic polymers such as ACCO® 711. The ACCO® family of adry strength materials are available from American Cyanamid Company of Wayne, N.J. Suitable chemical softening compositions are disclosed in U.S.
Pat. No. 5,279,767 issued Jan. 18, 1994 to Phan et al. Suitable biodegradable °chemical softening compositions are disclosed in U.S. Pat. No. 5,312,522 issued May 17, 1994 to Phan et al.
The embryonic web 543 is prepared from an aqueous dispersion of papermaking fibers, though dispersions in liquids other than water can be used. The fibers are dispersed in the carrier liquid to have a consistency of from about 0.1 to about 0.3 percent. The percent consistency of a dispersion, slurry, web, or other system is defined as 100 times the quotient obtained when the weight of dry fiber in the system under consideration is divided by the total weight of the system. Fiber weight is always expressed on the basis of bone dry fibers.
The embryonic web 543 can be formed in a continuous papermaking process, as shown in Figure 9, or alternatively, a batch process, such as a handsheet making process can be used. After the dispersion of papermaking fibers is deposited onto the forming belt 542, the embryonic web 543 is formed by removal of a portion of the aqueous dispersing medium by techniques well known to those skilled in the art. The embryonic web is generally monoplanar.
Vacuum boxes, forming boards, hydrofoils, and the like are useful in effecting water removal from the dispersion. The embryonic web 543 travels with the forming belt 542 about a return roll 502 and is brought into the proximity of the web support apparatus 200.
The next step in making the paper structure 20 comprises transferring 20 the embryonic web 543 from the forming belt 542 to the web support apparatus 200 and supporting the embryonic web 543 on the first side 202 of the web support apparatus. The embryonic web has a consistency of at least 8 percent at the point of transfer to the web support apparatus 200. The step of transferring the embryonic web 543 can simultaneously include the step of 25 deflecting a portion of the web 543. Alternatively, the step of deflecting a portion of the web 543 can follow the step of transferring the web.
The steps of transferring the embryonic web 543 to the web support apparatus 200 and deflecting a portion of the embryonic web 543 can be provided, at least in part, by applying a differential fluid pressure to the embryonic web 543. For instance, the embryonic web 543 can be vacuum transferred from the forming belt 542 to the web support apparatus 200 by a see.
Ce S 09 0 0 s o
C.
C 0C
C
06.0 0 9 9 *60000
C
9**e 0 0
C.
CS C me
C
vacuum source 600 depicted in Figure 9, such as a vacuum shoe or a vacuum roll. One or more additional vacuum sources 620 can also be provided downstream of the embryonic web transfer point.
Referring to Figures 9 and 10, the step of deflecting the web 543 comprises deflecting a portion of the web 543 overlying the first felt surface 230 in a first deflection step to form a non-monoplanar web 545 having a first uncompacted web region 547 supported on the first web contacting surface 230, and a second uncompacted web region 549 supported on the web contacting surface 260. The first deflection step is performed at a web consistency of between 8 percent and 30 percent, and preferably at a web consistency of between 8 percent and 20 percent, so that deflection of the web takes place when the fibers of the web 543 are relatively mobile, and so that the deflection does not result in breaking of substantial numbers of fiber to fiber bonds. The pressure differential provided by the vacuum source 600 can be between about 10 to about 25 inches of mercury. U.S. Pat. No. 4,529,480 issued Jul. 16, 1985 to Trokhan is incorporated herein by reference for the purpose of teaching transfer and deflection of an embryonic web by applying a differential fluid pressure.
After transferring and deflecting the embryonic web 543 to form the 20 nonmonoplanar web 545, the web 545 is carried on the web support apparatus 200 through a nip 800 provided between a compaction surface 875 and a deformable compression surface 910 of a compression member shown in Figure 11. The compression member can comprise a roller 900. The web 545 is carried through the nip 800 for positioning of the web 545 adjacent the compaction surface 875, and for positioning the second side 202 of the web support apparatus 200 adjacent the deformable compression surface 910.
The web 545 preferably enters the nip 800 at a consistency of between about 20 percent and about 50 percent.
The compaction surface 875 is preferably characterized in having a relatively high hardness and in being relatively incompressible as compared to the deformable compression surface 910. A suitable surface 875 is the 0.69 0 so a 0
OSSS
0005 0 0 6 00000 0 4 0 S 0 @0 00 .0 0
S
6 5
S
S
o OS S @0 I. surface of a steel or iron heated dryer drum 880. The surface 875 can be coated with a creping adhesive dispensed from a spray nozzle 890 located upstream of the nip 800, or alternatively, by an impression roll (not shown).
Alternatively, the creping adhesive can be applied to the pressed web 546 by any suitable means of glue application. A suitable creping adhesive is shown in U.S. Pat. No. 3,926,716 issued to Bates on Dec. 16, 1975, which patent is incorporated by reference.
Referring to Figure 11, the roller 900 can have an inner core 902 and an outer layer 906. The roller 900 can have a diameter of about 1-3 feet, and the dryer drum 880 can have a diameter of about 12-18 feet. The deformable compression surface 910 is preferably located on a layer 906 formed from a material having a P&J hardness less than about 120 P&J and preferably between about 30 and about 100 P&J. In one embodiment, the inner core 902 can be formed from a material such as steel, and the outer layer 906 comprising the surface 910 can be formed from natural rubber or other generally elastomeric materials.
The roller 900 can compose a vacuum pressure roll. Suitable vacuum pressure rolls have a drilled or grooved surface 910 through which vacuum is applied to the back side 202 of the web support apparatus 200 to provide 20 dewatering of the paper web in the nip 800. The vacuum applied ranges from about 0 to 15 inches of Mercury preferably between 3 and 12 inches of Mercury.
The next step in forming the paper structure 20 comprises pressing the web support apparatus 200 and the non-monoplanar web 545 between the 25 compression surface 910 and the compaction surface 875 to provide a average nip compression pressure of at least about 100 psi and preferably at least about 200 psi. The nip pressure is the total force applied to the nip divided by the nip area. The total force applied to the nip can be determined from hydraulic gauge readings coupled with a force balance analysis based on the equipment geometry. The nip width is determined by loading the nip 900 with a sheet of white paper and a sheet of carbon paper positioned between 0 *OO0 0000
OO..
O
O
OOO
OO0
S
0@ S oooo ooooo 00 oooo
S
ooo
S
00@0
S
0
OSOS
o o 0 0 0 00 00 0 ooo* oo5 oo the apparatus 200 and the surface 875, such that the carbon paper provides an impression of the nip width on the white paper.
Pressing the web support apparatus 200 and the web 545 in the nip 800 provides a second deflection step. The second deflection step comprises deflecting the first felt surface 230 relative to the web contacting top surface 260. In particular, the first web contacting surface 230 is deflected toward the compaction surface 875 by the deformable compression surface 910, as shown in Figure 11, thereby temporarily reducing, and temporarily substantially eliminating the difference in elevation 262 between a portion of the first felt surface 230 and the surface 260.
Deflecting the first web contacting surface 230 relative to the second web contacting surface 260 provides deflection of the first uncompacted web region 547 relative to the second uncompacted web region 549, thereby temporarily reducing the difference in elevation between the first and second web regions 547 and 549. In particular, a portion of the first web region 547 is deflected toward the compaction surface 875 by the first felt surface 230, to thereby temporarily substantially eliminate the difference in elevation between the first and second uncompacted web regions 547 and 549. The second S: deflection step is performed at a web consistency of between about 20 percent and about 80 percent, and preferably at a web consistency of lo* between about 30 percent and about 70 percent.
Pressing the web support apparatus 200 and the web 545 in the nip 800 also provides a web compaction step. Compacting a region of a web reduces the thickness of that region of the web. The web compaction step comprises the step of compacting a portion of the first generally uncompacted :web region 547 against the compaction surface 875 to form a first compacted web region 530, and compacting at least a portion of the second uncompacted web region 549 against the compaction surface 875 to form a second :I compacted web region 550. In particular, the web region 547 is compacted between the first felt surface 230 and the compaction surface 875, and the Y I web region 549 is compacted between the web contacting top surface 260 of the web patterning layer 250 and the compaction surface 875. The difference in elevation between the first and second compacted web regions 530 and 550 is essentially zero at the end of the compaction step, as both of the regions 530 and 550 are pressed into engagement with the compaction surface 875 of the dryer drum 880, as shown in Figure 11.
Relative deflection of the first felt surface 230 and the web contacting top surface 260 of the web imprinting layer 250 in the second deflection step is accomplished with a web support apparatus 200 and compression surface 910 having a combination of desired characteristics. One characteristic that enables such relative deflection is the bending flexibility of the web support apparatus 200.
The bending flexibility of the web support apparatus 200 is a function of the flexibility of the dewatering felt layer 220 and the stiffness imparted to the apparatus 200 by the web patterning layer 250. The web support apparatus 200 having a web patterning layer 250 with top surface 260 having the above described projected area and disposed to inscribe large portions of the felt surface 230 is relatively flexible compared to a structure having a larger percentage of its surface covered by resin. Such flexibility permits the deflection of the first felt surface 230 relative to the surface 260. In addition, spacing between adjacent web patterning elements 280 which is large relative to the elevation difference 262 reduces the bending stiffness of the felt layer 220 intermediate the elements 280, and permits the felt layer 220 intermediate the elements 280 to be deflected so that the first uncompacted web region 547 can be pressed into engagement with the compaction surface 875.
Another factor which affects relative deflection of the surfaces 230 and 260 is the hardness of the web patterning layer 250. A resin having a low hardness when cured will be compressed to some degree in the nip 800, thereby reducing the difference in elevation between the surfaces 260 and 230. Relative deflection of the
SS
S
surfaces 230 and 260 is also enhanced by reducing the hardness of the compression surface 910. A relatively low hardness compression surface 910 can conform to the second felt surface 232, and thereby provide a compressive load intermediate the web patterning elements 280 to press the first felt surface 230 and the first uncompacted web region 547 toward the compaction surface 875. Yet another factor which affects the relative deflection of the surfaces 230 and 260 is the degree of penetration of the web patterning layer 250 through the thickness of the felt layer 220. In general, a web patterning 250 that extends through less than about half the thickness of felt layer 220 is desirable to enhance relative deflection of surfaces 230 and 260.
The step of compacting the first and second uncompacted web regions 547 and 549 to form the compacted web regions 530 and 550 preferably also comprises the step of adhering at least a portion of the first and second compacted web regions 530 and 550 to the compaction surface 875, as shown in Figure II. The compacted web regions 530 and 550 can be adhered to the surface 875 by the creping adhesive applied to the surface 875 by the nozzle 890. After the compaction step, the web is dried on the heated surface 875 to have a consistency of greater than about percent.
The final step in forming the paper structure 20 comprises restoring at least some of the difference in elevation between the web regions 547 and 549 lost in the second deflection step. This restoring step provides the first region 30 at the first elevation 32 (corresponding to the first compacted web region 530), the second region 50 at the second elevation 52 (corresponding to the second compacted web region 550).
The step of restoring some of the difference in web elevation lost in the second 30 deflection step preferably comprises releasing the web from the compaction surface 875. In a preferred embodiment the step of restoring some of the difference in web elevation comprises foreshortening the web concurrently with the step of releasing the web from the compaction surface 875. Preferably, the step of releasing and foreshortening the web comprises the step of creping the web from the surface 875 with a doctor blade 1000, as shown in Figure 9.
As used herein, foreshortening refers to the reduction in length of the web which occurs when energy is applied to the dry web in such a way that the length of the web is reduced in the machine direction. Foreshortening can be accomplished in any of several ways. The most common and preferred way to foreshorten a web is by creping. The web adhered to the compaction surface 875 is removed from the surface 875 by the doctor blade 1000. In general, the doctor blade has a bevel angle of about 25 degrees and is positioned with respect to the Yankee dryer to provide an impact angle of about 81 degrees.
ANALYTICAL PROCEDURES Measurement of Thickness and Elevation The thicknesses and elevations of various regions 30-70 of a sample of the fibrous structure 20 are measured from microtomes made from cross-sections of the paper structure 20. A sample measuring about 2.54 centimeters by 5.1 centimeters (1 inch by 2 inches) is provided and stapled onto a rigid cardboard holder. The cardboard holder is placed in a silicon mold. The paper sample is immersed in a resin such as Merigraph photopolymer manufactured by Hercules, Inc.
The sample is cured to harden the resin mixture. The sample is removed from the silicon mold. Prior to immersion in photopolymer the sample is marked with a reference point to accurately determine where microtome slices are made.
Preferably, the same reference point is utilized in both the plan view and various sectional views of the sample of the fibrous structure The sample is placed in a model 860 microtome sold by the American Optical Company of Buffalo, New York and leveled. The edge of the sample is removed from the sample, in slices, by the microtome until a smooth surface appears.
A sufficient number of slices are removed from the sample, so that the various regions 30-70 may be accurately reconstructed. For the embodiment described herein, slices having a thickness of about 60 microns per slice are taken from the smooth surface. Multiple slices may be required so that the thicknesses 31, 51, and 71 may be ascertained.
30 A sample slice is mounted on a microscope slide using oil and a cover slip.
~The slide and the sample are mounted in a light transmission microscope and observed at about 40X magnification. Photomicrographs are taken along the slice, and the individual photomicrographs are arranged in series to reconstruct the profile of the slice. The thicknesses and elevations may be ascertained from the S1. 35 reconstructed profile, as shown in Figures 6A and 6B. By knowing the relative basis weights of individual regions, as well as the corresponding thicknesses of the individual regions, the density of the individual regions can be ascertained. U.S.
Patent 5,277,761 issued January 11, 1994 in the name of Phan et al. is incorporated herein by reference for describing the micro basis weight of individual regions of a paper structure.
The thickness between regions 31-71 may be established by using Hewlett Packard ScanJet IIC color flatbed scanner. The Hewlett Packard Scanning software is DeskScan II version 1.6 The scanner settings type is black and white photo. The path is LaserWriter NT, NTX. The brightness and contrast setting is 125. The scaling is 100%. The file is scanned and saved in a picture file format on a Macintosh IICi computer. The picture file is opened with a suitable photo-imaging software package or CAD program, such as PowerDraw version Referring to Figure 6B. the thickness of each region can be determined by drawing a circle which is inscribed by the region. The thickness of the region at that point is the diameter of the smallest circle that can be drawn in the region (in the microtome sample), multiplied by the appropriate scale factor. The scale factor is the magnification of the photomicrograph multiplied by the magnification of the scanned image. The circle can be drawn using any appropriate software drawing package, such as PowerDraw, version 5.0, available from Engineered Software of North Carolina.
The difference in elevation 62 is measured by drawing the smallest circle inscribed by region 50 (in the microtome sample), and by drawing two circles inscribed by region 30. as shown in Figure 6B. A first line LI is drawn tangent to the two circles inscribed by region 30. A second line L2 is drawn parallel to the first line L l and tangent to circle inscribed by region 50. The distance between the first and second lines, multiplied by the appropriate scale factor, is the difference in S* elevation 62.
Projected Area Measurement The projected area of the web contacting surface 260 is measured according to the following procedure. First, the web contacting surface 260 is darkened with a black marker (Sanford Sharpie) to increase the contrast. Second, three digitized 30 images of the we6 patterning apparatus 200 are acquired using a Hewlett Packard ScanJet IIc Flatbed scanner. The scanner options are set as follows: Brightness 198, contrast 211, black and white photo resolution 100 DPI scaling 100%. Third, the Spercentage of the projected area of the web support apparatus 200 comprising the web contacting surface 260 is determined using a suitable image analysis software system such as Optimas available from Bioscan, Incorporated, Edmonds, WA. The ratio of the number of pixels having a greyscale value between 0 and 62 (corresponding to the web contacting surface 260) is divided by the total number of pixels in the scanned image (times 100) to determine the percentage of the projected area of the web support apparatus 200 comprising the web contacting surface 260.
Measurement of Web Support Apparatus Elevations 29 The elevation difference 262 between the elevation 231 of the first felt surface and the elevation 261 of the web contacting surface 260 is measured using the following procedure. The web support apparatus is supported on a flat horizontal surface with the web patterning layer facing upward. A stylus having a circular contact surface of about 1.3 square millimeters and a vertical length of about 3 millimeters is mounted on a Federal Products dimensioning gauge (model 432B-81 amplifier modified for use with an EMD-4320 W1 breakaway probe) manufactured by the Federal Products Company of Providence. Rhode Island. The instrument is calibrated by determining the voltage difference between two precision shims of known thickness which provide a known elevation difference. The instrument is zeroed at an elevation slightly lower than the first felt surface 230 to insure unrestricted travel of the stylus. The stylus is placed over the elevation of interest and lowered to make the measurement. The stylus exerts a pressure of about 0.24 grams/square millimeter at the point of measurement. At least three measurements are made at each elevation. The difference in the average measurements of the 20 individual elevations 23 1 and 261 is taken as the elevation difference 262.
0* 6 Measurement of P&J Hardness The surface hardness of the roll 900 is measured using a P&J plastometer .6 Model 2000 manufactured by Dominion Engineering Works LTD of Lachine, Quebec, Ontario. The indentor shaft has a 3.17 millimeter ball. The hardness is taken at three different positions: One in the middle of the roll, one 6 inches from 6* one end of the roll, and one 6 inches from the other end of the roll. The P&J hardness is the average of these three readings. The readings are made with the roll conditioned at a temperature of 21 degrees Celsius following the procedure provided 30 by the manufacturer of the plastometer.
EXAMPLES
The following examples are provided to illustrate paper making according to embodiments of the present invention.
EXAMPLE 1 A 3% by weight aqueous slurry of Northern Softwood Kraft (NSK) fibers is made using a conventional re-pulper. The NSK slurry is refined gently (no load) and a 2% solution of the temporary wet strength resin National Starch 78-0080 marketed by National Starch and Chemical corporation of New-York, is added to the NSK stock pipe at a rate of 0.02% by weight of the dry fibers. The NSK slurry is diluted to about 0.2% consistency at the fan pump. Second, a 3% by weight aqueous slurry of Eucalyptus fibers is made up using a conventional re-pulper. The Eucalyptus slurry is diluted to about 0.2% consistency at the fan pump.
Three individually treated furnish streams (stream 1=100%
NSK;
stream 2=100% Eucalyptus; stream 3=100% Eucalyptus) are kept separate through the headbox and deposited onto a Fourdrinier wire to form a three layer embryonic web containing outer Eucalyptus layers and a middle
NSK
layer. Dewatering occurs through the Fourdrinier wire and is assisted by a deflector and vacuum boxes. The Fourdrinier wire is of a 5-shed, satin weave 20 configuration having 110 machine-direction and 95 cross-machine-direction monofilaments per inch, respectively.
The embryonic wet web is transferred from the Fourdrinier wire, at a fiber consistency of about 8% at the point of transfer, to a web support apparatus 200 having a dewatering felt layer 220 and a photosensitive resin web patterning layer 250.
The dewatering felt 220 is a Amflex 2 Press Felt manufactured by Appleton Mills of Appleton, Wisconsin. The felt 220 comprises a batt of polyester fibers. The batt has a surface denier of 3, a substrate denier of 15. The felt layer 220 has a basis weight of 1436 gin/square meter, a caliper of about 3 millimeter, and an air permeability of about 30 to about 40 scfm.
The web patterning layer 250 comprises discrete web patterning elements 280 having a flower-like shape, as shown in FIG. 4. The web patterning layer 250 has a projected area equal to about 10 percent of the projected area of the web support apparatus 200. The difference in elevation 262 between the top web contacting surface 260 and the first felt surface 230 is about 0.025 inch (0.633 millimeter).
The embryonic web is transferred to the web support apparatus 200 and deflected in a first deflection step to form a generally uncompacted, nonmonoplanar web 545. Transfer and deflection are provided at the vacuum transfer point with a pressure differential of about 20 inches of mercury.
Further de-watering is *q *oeo accomplished by vacuum assisted drainage until the web has a fiber consistency of about 25%. The web 545 is carried to the nip 800. The roll 900 has a compression surface 910 having a hardness of about 40 P&J. The web 545 is then deflected and compacted against the compaction surface 875 of the Yankee dryer drum 880 by pressing the web 545 and the web support apparatus 200 between the compression surface 910 and the Yankee dryer drum 880 surface at a compression pressure of about 200 psi. A polyvinyl alcohol based creping adhesive is used to adhere the compacted web to the Yankee dryer. The fiber consistency is increased to at least about 90% before dry creping the web with a doctor blade. The doctor blade has a bevel angle of about 25 degrees and is positioned with respect to the Yankee dryer to provide an impact angle of about 81 degrees; the Yankee dryer is operated at about 800 fpm (feet per minute) (about 244 meters per minute). The dry web is formed into roll at a speed of 650 fpm (200 meters per minutes).
The web is converted into a three-layer, one-ply toilet tissue paper. The one-ply toilet tissue paper has a basis weight of about 18 pounds per 3000 square feet. and 20 contains about 0.02% of the temporary wet strength resin. The resulting one-ply Stissue paper is soft absorbent, and is suitable for use as toilet tissues.
EXAMPLE 2 A 3% by weight aqueous slurry of Northern Softwood Kraft is made up in a conventional re-pulper. The NSK slurry is refined gently (no load) and a 2% solution of the permanent wet strength resin Kymene® 557H marketed by Hercules Incorporated of Wilmington, Delaware) is added to the NSK stock pipe at a rate of 0.02% by weight of the dry fibers followed by the addition of a 1% solution of the dry strength resin CMC from Hercules Incorporated of Wilmington, Delaware) is added to the NSK stock before the fan pump at a rate of 0.08% by weight of the dry fibers. The NSK slurry is diluted to about 0.2% consistency at the fan pump. Second, a 3% by weight aqueous slurry of Eucalyptus fibers is made up in a conventional re- S* pulper. The Eucalyptus slurry is diluted to about 0.2% consistency at the fan pump.
The two individually treated furnish streams (stream 1 100% NSK; stream 2 100% Eucalyptus) are kept separate through the headbox and deposited onto a Fourdrinier wire to form an NSK layer and a Eucalyptus layer. Dewatering occurs through the Fourdrinier wire and is assisted by a deflector and vacuum boxes. The Fourdrinier wire is of a 5-shed, satin weave configuration having 110 machinedirection and 95 cross-machine-direction monofilaments per inch, respectively.
The embryonic wet web is transferred from the Fourdrinier wire, at a fiber consistency of about 8% at the point of transfer, to a web support apparatus 200 having a dewatering felt layer 220 and a photosensitive resin web patterning layer 250.
The dewatering felt 220 is a Amflex 2 Press Felt manufactured by Appleton Mills of Appleton, Wisconsin. The web patterning layer 250 comprises discrete web patterning elements 280 having a flower-like shape, as shown in Figure 4. The web patterning layer 250 has a projected area equal to about 10 percent of the projected area of the web support apparatus 200. The difference in elevation 262 between the top web contacting surface 260 and the first felt surface 230 is about 0.025 inch (0.633 millimeter).
The embryonic web is transferred to the web support apparatus 200 and deflected in a first deflection step to form a generally uncompacted, nonmonoplanar web 545. Transfer and deflection are provided at the vacuum transfer point with a pressure differential of about 20 inches of mercury.
Further de-watering is accomplished by vacuum assisted drainage until the web has a fiber consistency of about 25%. The web 545 is carried by the web support apparatus 200 to the nip 800. The roll 900 has a compression surface 910 having a hardness of about 40 P&J. The web 545 is then deflected and compacted against the compaction surface 875 of the Yankee dryer drum 880 *by pressing the web 545 and the web support apparatus 200 between the *compression surface 910 and the Yankee dryer drum 880 surface at a ocompression pressure of at least about 200 psi. A polyvinyl alcohol based creping adhesive is used to adhere the compacted web to the Yankee dryer.
25 The fiber consistency is increased to at least about 90% before dry creping the web from the surface of the dryer drum 880 with a doctor blade. The doctor blade has a bevel angle of about 25 degrees and is positioned with S: respect to the Yankee dryer to provide an impact angle of about 81 degrees; the Yankee dryer is operated at about 800 fpm (feet per minute) (about 244 meters per minute). The dry web is formed into roll at a speed of 650 fpm R(200 meters per minutes).
32a The web is converted to provide a two-layer, two-ply facial tissue paper.
Each ply of the two-ply facial tissue paper has a basis weight about 10 pounds per 3000 square feet, and contains about 0.02% by weight of the permanent wet strength resin and about 0.08% by weight of the dry strength resin. The resulting two-ply tissue paper is soft, absorbent, and is suitable for use as a facial tissue.
The term "comprises" and its grammatical variations such as "comprising" when used in the description and claims does not preclude the presence of additional features, integers, or steps or components, or groups thereof.
oo t, •go• •*oo *go* o• a

Claims (11)

1. A method of forming a paper web, the method including the steps of: providing a generally uncompacted, generally monoplanar wet web of paper making fibers; deflecting the web at a consistency of between 8 and 30 percent in a first deflection step to provide a non-monoplanar web having a first region at a first elevation and a second region at a second elevation different from the first elevation; deflecting the first region relative to the second region in a second deflection step to reduce the difference in elevation between the first web region and the second web region in a second deflection step at a web consistency of between 20 and 80 percent; compacting at least a portion of the first web region at a consistency of between 20 and 80 percent to provide a first compacted web region; compacting at least a portion of the second web region at a consistency of between 20 and 80 percent to provide a second compacted web region; and restoring at least some of the difference in elevation between the first web region and the second web region to provide a first compacted web region disposed at a first elevation and a second compacted web region disposed at a second elevation different from the first elevation.
2. The method of claim 1 characterized in the restoring step includes foreshortening the first and second compacted regions after compacting the web.
The method of claim 1 or 2 including the step of imparting a variable frequency crepe pattern to a portion of the web bordering at least a portion of Sthe second compacted web region. 34
4. The method of any one of claims 1 to 3 characterized in that the step of deflecting the web in the first deflection step comprises providing a differential fluid pressure across the thickness of the web.
The method of any one of claims 1 to 4 further including the step of drying the web to a consistency of between 85 percent and 100 percent after the compacting steps and prior to the restoring step.
6. The method of any one of claims 1 to 5 characterized in that the steps of compacting at least a portion of the first and second web regions include the steps of: providing a compaction surface; 0.00 compacting at least a portion of the first web region against the 0compaction surface; and 00* compacting at least a portion of the second web region against the compaction surface. S
7. The method of claim 6 further including the steps of adhering at least a portion of the first compacted to the compaction surface and adhering at least a portion of the second compacted web region to the compaction surface. .O
8. The method of claim 1 including the steps of: afrtproviding a web support apparatus having a dewatering felt layer having S°a first web facing felt surface at an elevation and a web patterning layer, the web patterning layer having a web contacting top surface at an elevation difference from the elevation of the first felt surface; providing a compaction surface; providing a source of differential fluid pressure; applying the differential fluid pressure to transfer the generally monoplanar web to the web support apparatus; supporting the web of paper making fibers on the web support apparatus; deflecting the web at a consistency of between 8 and 30 percent in a first deflection step to provide a non-monoplanar web having a first region at a first elevation, the first region supported on the first felt surface; and a second region at a second elevation different from the first elevation, the second region supported on the web contacting top surface; deflecting the first felt surface relative to the web contacting surface of the web patterning layer to reduce the difference in elevation between the first web region and the second web region in a second deflection step; compacting at least a portion of the first web region against the compaction surface at a consistency of between 20 and 80 percent to provide a first compacted web region; and compacting at least a portion of the second web region against the compaction surface at a consistency of between 20 and 80 percent to provide a second compacted web region.
9. The method of claim 8 further including the steps of: drying the web to a consistency of 85 and 100 percent after compacting the first and second web region; and foreshortening the first and second compacted web region.
10. The method of claim 9 characterized in that the second deflection step Sg and the steps of compacting the first and second web regions include: providing a deformable compression surface having a hardness less than the hardness of the compaction surface; providing a nip between the deformable compression surface and the compaction surface; positioning the web in the nip intermediate the web support apparatus and the compaction surface; positioning the web support apparatus intermediate the web and the deformable compression surface; and pressing the web support apparatus and the web between the deformable compression surface and the compaction surface. 36
11. The method of claim 1 substantially as hereinbefore described with reference to the examples. DATED this 23rd day of February, 1999 THE PROCTER GAMBLE COMPANY WATERMARK PATENT TRADEMARK ATTORNEYS 290 BURWOOD ROAD HAWTHORN VICTORIA 3122 AUSTRALIA DOC 25 AUoo2997.wPC LCG/JGC/MEH Go:* 0000 *0 a to
AU18400/99A 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same Ceased AU731653B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU18400/99A AU731653B2 (en) 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/268213 1994-06-29
AU27060/95A AU704258C (en) 1994-06-29 1995-06-19 Paper structure having at least three regions, and apparatus and process for making the same
AU18400/99A AU731653B2 (en) 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
AU27060/95A Division AU704258C (en) 1994-06-29 1995-06-19 Paper structure having at least three regions, and apparatus and process for making the same

Publications (2)

Publication Number Publication Date
AU1840099A AU1840099A (en) 1999-05-06
AU731653B2 true AU731653B2 (en) 2001-04-05

Family

ID=3715440

Family Applications (3)

Application Number Title Priority Date Filing Date
AU18400/99A Ceased AU731653B2 (en) 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same
AU18401/99A Ceased AU731649B2 (en) 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same
AU18402/99A Ceased AU731534B2 (en) 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same

Family Applications After (2)

Application Number Title Priority Date Filing Date
AU18401/99A Ceased AU731649B2 (en) 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same
AU18402/99A Ceased AU731534B2 (en) 1994-06-29 1999-02-23 Paper structure having at least three regions, and apparatus and process for making the same

Country Status (1)

Country Link
AU (3) AU731653B2 (en)

Also Published As

Publication number Publication date
AU1840299A (en) 1999-05-13
AU1840099A (en) 1999-05-06
AU1840199A (en) 1999-05-06
AU731534B2 (en) 2001-03-29
AU731649B2 (en) 2001-04-05

Similar Documents

Publication Publication Date Title
EP0801697B1 (en) Paper structure having at least three regions, and apparatus and process for making the same
EP0767850B1 (en) Web patterning apparatus comprising a felt layer and a photosensitive resin layer and method of forming the apparatus
US5871887A (en) Web patterning apparatus comprising a felt layer and a photosensitive resin layer
US5549790A (en) Multi-region paper structures having a transition region interconnecting relatively thinner regions disposed at different elevations, and apparatus and process for making the same
CA2514603C (en) Unitary fibrous structure comprising cellulosic and synthetic fibers and process for making same
AU2004211618B2 (en) Process for making unitary fibrous structure comprising randomly distributed cellulosic fibers and non-randomly distributed synthetic fibers and unitary fibrous structure made thereby
CA2271863A1 (en) Method for making paper web having both bulk and smoothness
CA2271640C (en) Improved drying for patterned paper webs
AU731653B2 (en) Paper structure having at least three regions, and apparatus and process for making the same
AU704258C (en) Paper structure having at least three regions, and apparatus and process for making the same
AU729557B2 (en) Multi-region paper structure and apparatus and process for making the same

Legal Events

Date Code Title Description
FGA Letters patent sealed or granted (standard patent)