Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3905863 A
Publication typeGrant
Publication date16 Sep 1975
Filing date1 Apr 1974
Priority date8 Jun 1973
Also published asCA1007911A1, DE2427291A1
Publication numberUS 3905863 A, US 3905863A, US-A-3905863, US3905863 A, US3905863A
InventorsAyers Peter G
Original AssigneeProcter & Gamble
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Process for forming absorbent paper by imprinting a semi-twill fabric knuckle pattern thereon prior to final drying and paper thereof
US 3905863 A
Abstract
A low-density, soft, bulky and absorbent paper sheet exhibiting a diamond-shaped pattern in its surface after creping, said paper being characterized by having a cross-directional stretch of from about 3.5 percent to about 6 percent, as well as improved softness, surface feel and drape, said paper sheet being particularly suitable for use in tissue, toweling and sanitary products. The aforesaid paper sheets are produced by impressing a dot-dash knuckle pattern, wherein the long axis of the dash impressions is aligned parallel to the machine direction of papermaking, using the back side of a monofilament, polymeric fiber, semi-twill fabric of selected coarseness, the knuckle imprint area of which constitutes between about 20 percent and about 50 percent of the total fabric surface area, as measured in the plane of the knuckles, on an uncompacted paper web at selected fiber consistencies, induced by thermal predrying, prior to final drying and creping.
Images(4)
Previous page
Next page
Description  (OCR text may contain errors)

United States Patent [191 Ayers [451 Sept. 16, 1975 THEREOF [75] Inventor: Peter G. Ayers, West Chester, Ohio [73] Assignee: The Procter & Gamble Company, Cincinnati, Ohio [22] Filed: Apr. 1, 1974 [21] App]. No.: 457,043

Related US. Application Data [63] Continuation-in-part of Ser. No. 368,440, June 8,

1973, abandoned.

[52] US. Cl. 162/113; 139/425 A; 156/183; 161/128; 162/116; 162/117 [51] Int. Cl. D21H 5/24 [58] Field of Search 162/113, 116, 117, 109; 139/425 A, 383 R; 161/128; 156/183 [56] References Cited UNITED STATES PATENTS 3,159,530 12/1964 Heller et a1. 130/425 AX 3,301,746 1/1967 Sanford et a1. 162/1 13 3,473,576 10/1969 Amneus 139/425 AX 3,573,164 3/1971 Friedberg et al.. 139/383 R 3,812,000 5/1974 Salvucci et 156/183 X 3,817,827 6/1974 Benz 162/113 3,821,068 6/1974 Shaw 156/183 X 12/1974 Egan 139/425 AX Primary Examiner-S. Leon Bashore Assistant Examiner-Arthur L. Corbin Attorney, Agent, or FirmE. Kelly Linman; Frederick H. Braun; John V. German [5 7] ABSTRACT A low-density, soft, bulky and absorbent paper sheet exhibiting a diamond-shaped pattern in its surface after creping, said paper being characterized by having a cross-directional stretch of from about 3.5 percent to about 6 percent, as well as improved softness, surface feel and drape, said paper sheet being particularly suitable for use in tissue, toweling and sanitary products. The aforesaid paper sheets are produced by impressing a dobdash knuck1e pattern, wherein the long axis of the dash impressions is aligned parallel to the machine direction of papermaking, using the back side of a monofilament, polymeric fiber, semi-twill fabric of selected coarseness, the knuckle imprint area of which constitutes between about 20 percent and about 50 percent of the total fabric surface area, as measured in the plane of the knuckles, on an uncompacted paper web at selected fiber consistencies, induced by thermal predrying, prior to final drying and creping.

6 Claims, 20 Drawing Figures PATENTED SEP 1 6 I975 SHEET L [1F 4 Fig. 17

Fig. 19

PROCESS FOR FORMING ABSORBENT PAPER BY IMPRINTING A SEMI-TWILL FABRIC KNUCKLE PATTERN THEREON PRIOR TO FINAL DRYING AND PAPER THEREOF CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of my copending application, Ser. No. 368,440, filed June 8, 1973, entitled PROCESS FOR FORMING ABSOR- BENT PAPER BY IMPRINTING A SEMI-TWILL FABRIC KNUCKLE PATTERN THEREON PRIOR TO FINAL DRYING AND PAPER THEREOF, now abandoned.

FIELD OF THE INVENTION This invention relates to improvements in papermaking and non-woven web manufacturing operations and particularly to the provision of a low-density, soft, bulky and absorbent paper sheet characterized by having significantly greater cross-directional stretch, as well as improved softness, surface feel and drape when compared to paper sheets produced by prior art papermaking and non-woven web manufacturing methods.

More particularly, in one important embodiment, the present invention consists of a monofilament, polymeric fiber, semi-twill fabric which when used to imprint an uncompacted paper web at selected fiber consistencies, induced by thermal pre-drying, will produce a dotdash pattern wherein the long axis of the dash impressions is aligned parallel to the machine direction of paper-making and the long axis of the dot impressions is aligned parallel to the cross-machine direction. The aforesaid imprinting fabric is especially suitable for use in papermaking and non-woven web manufacturing operations, such as the papermaking operation disclosed in U.S. Pat. No. 3,301,746, issued to Sanford et al. on Jan. 31, 1967, said patent being incorporated herein by reference, wherein the surface characteristics of such fabrics are of operational and product characteristic importance.

In one preferred cmbodimen, the present invention consists of a monofilament, polymeric fiber, semi-twill fabric of the type normally used for transporting a moist web through the forming, pressing and drying sections of a papermaking machine, which monofilament, polymeric fiber, semi-twill fabric is woven and thereafter shrunk by heat treatment to result in a dimensionally heat stable fabric having uniform knuckle heights in conjunction with minimum free or interstitial area on the surface of the fabric which will contact the uncompacted paper web, said fabric having been further improved by abrading its web contacting sur face with a fine abrasive medium to increase its knuckle imprint area.

BACKGROUND OF THE INVENTION In a Fourdrinier paper machine, paper stock is fed onto a traveling endless belt that is supported and driven by rolls associated with the machine and which serves to the papermaking surface of the machine. Foundrinier belts are commonly formed from a length of woven Fourdrinier fabric with its ends joined together in a seam to provide an endless belt. Fourdrinier fabrics of this type generally comprise a plurality of spaced longitudinal warp filaments and a plurality of spaced transverse woof or weft filaments which have been woven together on a suitable loom. It should be noted that the warp filaments of the fabric are, for purposes of this specification, defined as those which run parallel to the machine direction of papermaking and non-woven web manufacturing machines to form a continuous carrier belt; woof or weft filaments are, for purposes of this specification, defined as those which run in the cross-machine direction.

Although the weaving and fabric treatment criteria of the present invention are applicable in other areas of monofilament, polymeric fiber fabric use, the instant features will be most readily understood in respect to the use of such fabrics for imprinting purposes in web formation operations. In these operations, for example in the operation of a paper machine according to the teachings of U.S. Pat. 3,301,746, improved web transferability and dryer surface contact are desirable in an imprinting fabric, and the monofilament, polymeric fiber fabric used should not contribute factors to the final paper product other than those desired by the papermaker and designed into the paper product.

In referring to monofilament, polymeric fiber fabrics herein, applicant intends reference to moist web carrier fabrics woven, for example, from the polyamide fibers, vinyl fibers, acrylic fibers and polyester fibers sold under the respective trade names of nylon, Saran, Orlon, Dacron, and Treviera. While both warp and woof filaments in fabrics can be made up of a multiplicity of fibers, the present invention is concerned with warp and woof filamentscomprised of one fiber, i.e., monofilaments.

While a number of different weaves have been proposed for Fourdrinier fabrics, two weaveswhich find extensive use today are the so-called plain weave and the semi-twill (sometimes also called long crimp) weave. In the plain weave, each weft filament passes successively under one warp filament and then over the next warp filament, whereas in the semi-twill weave each weft filament passes over two warp filaments, under the next warp filament, and then over the next two warp filaments in a repeated pattern. Of these two weaves, the semi-twill weave is the most widely used.

The imprinting fabric suggested for use in U.S. Pat. 3,301,746, to which the present invention has particular relevance, may be of square or diagonal weave, and can be of any specific construction including, for example, plain or semi-twill weave. A preferred imprinting fabric, according to the teachings of the aforesaid Sanford et a1. patent, has about 20 to about 60 meshes per inch and is formed from filaments having a diameter of from about 0.008 to about 0.02 inches.

Paper sheets produced in accordance with the teachings of U.S. Pat. No. 3,301,746 utilizing a monofilament, polymeric fiber, semi-twill imprinting fabric exhibit properties similar in most respects to paper sheets produced utilizing a plain weave imprinting fabric having filaments of approximately the same diameter when the semi-twill fabric is installed so that its conventional face side is used to imprint the uncompacted paper web. This is due to the fact that the conventional face side of the semi-twill fabric, assuming the fabric has uniform knuckle heights on its web contacting side, will produce a dot-dash pattern wherein the long axis of the dash impressions is aligned parallel to the crossmachine direction and the long axis of the dot impressions is aligned parallel to the machine direction. The dash impressions result from each weft filament passing in a repeated pattern under one: warp filament and then over the next two warp filaments, while the dot impressions result from each warp filament passing in a repeated pattern over one weft filament and then under the next two weft filaments on the conventional face side of the fabric.

When paper sheets imprinted by the conventional face side of a semi-twill fabric, as described above, are doctored from the drying drum, the dot-dash knuckle impressions are aligned essentially between the creping folds. The resulting creping folds are, therefore, substantially uninterrupted across the sheets surface. Thus paper sheets produced utilizing the conventional face side of a semi-twill imprinting fabric exhibit properties substantially similar to paper sheets produced utilizing a plain weave imprinting fabric, i.e., a low-density, soft, bulky and absorbent paper sheet characterized by having .uniforrncreping folds which extend substantially uninterrupted across the width of the sheet.

On the other hand, utilization of the back side of a monofilament polymeric fiber, semi-twill fabric to imprint an uncompacted paper web in accordance with the teachings of U.S. Pat. No. 3,301,746 will, assuming the fabric has uniform knuckle heights on its web contacting side, produce a dot-dash pattern wherein the long axis of the dash impressions is aligned parallel to the machine direction of the paper machine and the longaxisof the dot impressions is aligned parallel to the cross-machine direction. The dash impressions result from each warp filament passing in a repeated pattern under one weft filament and then over the next two weft filaments, while the dot impressions result from each weft filament passing in a repeated pattern over one'warp filament and then under the next two warp filaments on the back side of the fabric.

Paper sheets imprinted with the back side of a conventional semi-twill, monofilament, polymeric fiber fabric, unlike paper sheets imprinted with either a plain weave fabric or the conventional face side of a semitwill fabric, exhibit a diamond-shaped pattern after creping.

Applicant has discovered that by increasing the knuckle'imprint area on the back side of a conventional semi-twill, monofilament, polymeric fiber fabric in accordance with the teachings of U.S. Pat. No. 3,573,164 issued to Friedberg et al. on Mar. 30, 1971, said patent being incorporated herein by reference. unexpected improvments in paper sheet characteristics can be realized. These unexpected advantages take the form of improved cross-directional stretch, softness, surface feel and drape. The improvements become more pronounced as the knuckle area on the back side of the semi-twill fabric is increased.

Although improved web transfer characteristics and improved drying of the web are realized when the web contacting knuckle surfaces of nearly any monofilament, polymeric fiber fabric are abraded in accordance with the teachings of U.S. Pat. No. 3,573,164, applicant has learned that the aforementioned improvements in cross-directional stretch, softness, surface feel and drape are realized only with respect to the back side of a semi-twill imprinting fabric, such as is described above.

In order to maximize the beneficial effects of abrading the knuckle surfaces on the back side of a semi-twill imprinting fabric, applicant has found it desirable to obtain a semi-twill fabric having uniform knuckle heights and minimum free area on its back side prior to initiating any abrading process. Uniform knuckle heights permit a greater increase in knuckle imprint 4 area while minimizing the danger of abrading completely through any particular filament. In addition, if knuckle heights are uniform prior to initiating any abrading process, the resulting imprint pattern after abrading will be more uniformly consistent.

Because a fabric such as is utilized for imprinting purposes in U.S. Pat. No. 3,301,746 is subjected to elevated temperatures during use, it is desirable to dimensionally heat stabilize the fabric prior to subjecting it to an abrading process to increase its knuckle imprint area. If this is not done, the uniform imprinting surface produced by carefully weaving the fabric and abrading the web contacting surface of the fabric prior to use will tend to warp as the temperature of the fabric becomes elevated, thereby losing most of the benefits to be obtained by such careful pre-treatment.

A means of preparing a dimensionally heat stable, plain weave, monofilament, polymeric fiber fabric having uniform knuckle heights and minimum free area on each side of the fabric is disclosed in U.S. Pat. No. 3,473,576 issued to Amneus on Oct. 21, 1969, said patent being incorporated herein by reference. A plain weave fabric is prepared by selecting polymeric warp monofilaments having a relatively high heat-induced shrinkage potential and further selecting an initial warp monofilament spacing in the loom according to a mathematical equation disclosed in the aforementioned Amneus patent. Polymeric woof monofilaments are then selected which have a relatively low heat induced shrinkage potential, and these woof monofilaments are woven and beaten in the weaving process into a plain weave fabric having an initial caliper calculated according to yet another mathematical equation disclosed in the aforementioned Amneus patent. After the initial weaving process, the fabric knuckles are brought to uniform on both sides of the fabric and the minimum free area of the fabric is set by a heat shrinkage treatment which maintains the fabric in warp tension while allowing it to shrink in the woof direction. Successive heat treatments are repeated until the monofilament, polymeric fiber, plain weave fabric does not shrink further at the treating temperature, at which point it is said to be locked-up, i.e., no further shrinkage will occur if the fabric is later subjected, in use, to elevated tempeatures equivalent to the treating temperature.

It is important to note that due to the symmetry of the plain weave, uniform knuckle heights and minimum free area are achieved simultaneously on both sides of the fabric when the weaving and heat treatment processes described in the aforementioned Amneus Patent are utilized. This is not the case with a semi-twill weave fabric. If a monofilament, polymeric fiber, semi-twill fabric is subjected to a heat treatment process similar to that disclosed in the Amneus patent, the knuckles on the conventional face side of the fabric will become coplanar before the knuckles on the back side of the fabric have reached a uniform height. Thus, in order for the knuckles on the back side of the fabric to become coplanar, the fabric must be subjected to further heat treatment. The additional heat treatment required to make the knuckle heights on the back side of the fabric uniform causes the knuckle heights on the conventional face side of the fabric to again become nonuniform.

Therefore, the initial warp filament spacing and caliper of a semi-twill fabric necessary to produce minimum free area and uniform knuckle heights on the back side of the fabric after heat treatment are determined experimentally by trial and error.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a low-density, bulky and absorbent creped paper structure exhibiting a diamond-shaped pattern in its surface, said paper structure having significanty improved softness, surface feel and drape, as well as significantly improved cross-directional stretch.

It is a further object of the present invention, in a preferred embodiment, to produce the above mentioned paper structure in accordance with the teachings of U.S. Pat. No. 3,301,746 by utilizing the back side of a conventional, monofilament, polymeric fiber, semitwill fabric which has been abraded in accordance with the teachings of U.S. Pat. No. 3,573,164 to imprint the uncompacted paper web prior to creping.

It is a further object of the present invention, in a preferred embodiment, to produce a paper structure in accordance with the teachings of U.S. Pat. No. 3,301,746 wherein a dot-dash pattern is imprinted on the uncompacted paper web, prior to creping, such that the long axis of the dash impressions is aligned parallel to the machine direction and the long axis of the clot impressions is aligned parallel to the cross-machine direction.

It is another object of the present invention, in a preferred embodiment, to provide dimensionally heat stable, monofilament, polymeric fiber, semi-twill fabrics for use in fibrous web carrying, imprinting, and other fabric using operations, which monofilament, polymeric fiber, semi-twill fabrics are characterized by having uniform knuckle heights and minimum free area on their back side, thus contributing materially to the avoidance of transfer and contact problems in papermaking and web formation operations.

It is a further object of the present invention, in a preferred embodiment, to provide a process for the production of dimensionally heat stable, monofilament, polymeric fiber, semi-twill fabrics, which process sets criteria for the weaving and heat treating operations necessary to achieve uniform knuckle heights and mini mum free area on the back side of said fabrics.

Another object of the present invention, in a preferred embodiment, is to provide a monofilament, polymeric fiber, semi-twill fabric for use in papermaking and non-woven web manufacturing operations, the back surface of which fabric has a total knuckle imprint area of from about percent to about 50 percent of the total fabric surface area, as measured in the plane of the knuckles, and which knuckle imprint area has a surface finish at least equal in smoothness to the surface finish induced by abrasion with an abrasive medium having an effective abrasive grain size-of less than about 300 mesh.

It is yet another object of the present invention, in a preferred embodiment, to provide a monofilament, polymeric fiber, semi-twill fabric for use in the imprinting and drying sections of a papermaking machine, the back side of which fabric presents an increased knuckle area to the moist paper web for use in pressing the web onto the surface of a dryer while it contributes materially to the final tensile strength of the dried paper product by avoiding the rupture of fiber bonds.

SUMMARY OF THE INVENTION In a preferred embodiment of the present invention, a low density, soft, bulky and absorbent paper sheet is provided, said paper sheet exhibiting a diamond 6 shaped pattern in its surface after creping, said paper sheet being characterized by having a cross-directional stretch of from about 2 percent to about 6 percent, as well as improved softness, surface feel and drape, said paper sheet being particularly suitable for use in tissue, toweling, and sanitary products.

The soft, bulky and absorbent paper sheets of the present invention are produced, in a preferred embodi ment, generally in accordance with the teachings of U.S. Pat. No. 3,301,746 by forming an uncompacted paper web, supporting said uncompacted paper web on the back side of a monofilament, polymeric fiber, semitwill imprinting fabric having about 20 to about 60 meshes per inch, said imprinting fabric having been formed from filaments having a diameter of from about 0.008 inches to about 0.025 inches, the back side of said fabric having had its knuckle imprint area increased in accordance with the teachings of U.S. Pat. No. 3,573,164, thermally pre-drying said uncompacted paper web to a fiber consistency of about 30 percent to about 98 percent, imprinting a dot-dash knuckle pattern with the back side of said semi-twill imprinting fabric such that the long axis of the dash impressions in said pattern is aligned parallel to the machine direction and the long axis of the dot impressions is aligned parallel to the cross-machine direction of the pre-dried uncompacted paper web, and final drying and creping the paper sheet so formed.

In a preferred embodiment of the present invention, the back side of the monofilament, polymeric fiber, semi-twill imprinting fabric is prepared in accordance with the teachings of U.S. Pat. No. 3,573,164 by abrading the knuckle surfaces to increase the knuckle imprint area to between about 20 percent and about 50 percent of the total fabric surface area, as measured in the plane of the knuckles, as well as to polish the knuckle surfaces.

In yet another preferred embodiment of the present invention, the monofilament, polymeric fiber, semitwill fabric is woven and heat treated so as to produce a dimensionally heat stable fabric having uniform knuckle heights and minimum free area on its back side prior to abrading the knuckle surfaces on the back side of the fabric.

BRIEF DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as the present invention, it is believed that the invention will be better understood from the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a plan view of an enlarged portion of a conventional right-hand semi-twill, monofilament, polymeric fiber fabric as viewed from the back side, i.e., that side of the fabric which according to the teachings of the prior art does not normally contact the web. The monofilament, polymeric fiber, semi-twill fabric is shown prior to any abrasion treatment and prior to use as an endless or continuous fabric belt in papermaking or non-woven web manufacturing operations.

FIG. 2 is an enlarged cross-sectional view of the semitwill fabric illustrated in FIG. 1, taken looking in the cross-machine direction (CD) along line 2-2 in FIG. 1, which crosssectional view illustrates the higher relative elevation and the smooth knuckle surfaces of the warp filaments on each side of the fabric.

FIG. 3 is an enlarged cross-sectional view of the semitwill fabricjillustrated in FIGS. 1 and 2, taken looking in themachine direction (MD) along line 3-3 in FIG. 1, which cross-sectional view illustrates the lower relative elevation and the smooth knuckle surfaces of the woof or weft filaments.

FIG. 4 is a simplified illustration of an'enlarged partial plan view of an uncreped paper sheet which has been imprinted utilizing the conventional face side of a semi-twill fabric such as is shown in FIGS. 1 through 3. The long axis of the dot impressions formed by the warp filaments is aligned parallel to the machine direction.

FIG. 5 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet which has been imprinted utilizing the back side of a semi-twill fabric such as is shown in FIG. 1 through 3. The long axis of the dash impressions formed by the warp filaments is aligned parallel to the machine direction.

FIG. 6 is an enlarged cross-sectional view of a monofilament, polymeric fiber, semi-twill fabric such as is illustrated in FIGS. 1 through 3, taken looking in the cross-machine direction at a point corresponding to line 22 in FIG. 1, after the fabric has been subjected to a heat treatment process sufficient to produce uniform knuckle heights on the conventional face side of the fabric.

FIG. 7 is an enlarged cross-sectional view of the semitwill fabric illustrated in FIG. 6, taken looking in the machine direction at a point corresponding to line 33 in FIG. 1.

FIG. 8 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet which has been imprinted utilizing the conventional face side of a monofilament, polymeric fiber, semi-twill fabric such as is illustrated in FIGS. 6 and 7. The long axis of the dash impressions formed by the woof or weft filaments is aligned parallel to the cross-machine direction, while the long axis of the dot impressions formed by the warp filaments is aligned parallel to the machine direction.

FIG. 9 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet which has been imprinted utilizing the back side of a semi-twill fabric such as is illustrated in FIGS. 6 and 7. The long axis of the dash impressions formed by the warp filaments is aligned parallel to the machine direction.

FIG. 10 is an enlarged cross-sectional view of a monofilament, polymeric fiber, semi-twill fabric such as is illustrated in FIGS. 1 through 3 and 6 and 7, taken looking in the cross-machine direction at a point corresponding to line 22 in FIG. 1, after the fabric has been subjected to a heat treatment process sufficient to produce uniform knuckle heights and minimum free area on the back side of the fabric. It should be noted that at this point, the knuckle heights on the conventional face side of the fabric are no longer uniform.

FIG. 11 is an enlarged cross-sectional view of the semi-twill fabric illustrated in FIG. 10, taken looking in the machine direction at a point corresponding to line 3-3 in FIG. 1.

FIG. 12 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet which has been imprinted utilizing the conventional face side of a semi-twill fabric such as is illustrated in FIGS. 10 and 1 l. The long axis of the dash impressions formed by the woof or weft filaments is aligned parallel to the crossmachine direction.

FIG. 13 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet which has been imprinted utilizing the back side of a semi-twill fabric such as is illustrated in FIGS. 10 and 11. The long axis of the dash impressions formed by the warp filaments is aligned parallel to the machine direction, while the long axis of the dot impressions formed by the woof or weft filaments is aligned parallel to the crossmachine direction. The dot impressions are present at this stage due to the fact that the knuckles 'on the back side of the fabric are of uniform height.

FIG. 14 is an enlarged cross-sectional view of a monofilament, polymeric fiber, semi-twill fabric such as is illustrated in FIGS. 10 and 11, taken looking in the cross-machine direction at a point corresponding to line 22 in FIG. 1, after the back side of the fabric has been abraded to increase its knuckle imprint area.

FIG. 15 is an enlarged cross-sectional view of the semi-twill fabric illustrated in FIG. 14, taken looking in the machine direction at a point corresponding to line 33 in FIG. 1.

FIG. 16 is a plan view of an enlarged portion of the monofilament, polymeric fiber, semi-twill fabric illustrated in FIGS. 14 and 15, as viewed from the back side of the fabric.

FIG. 17 is a plan view photograph, enlarged about 12 times actual size, of an uncreped paper sheet which has been imprinted utilizing the back side of a semi-twill fabric such as is shown in FIGS. 14, 15, and 16. The pattern produced is similar to that shown in FIG. 13, but the dot-dash impressions constitute a greater percentage of the surface area of the paper due to the increased knuckle imprint area of the fabric.

FIG. 18 is an illustration of an enlarged cross-sectional view of the uncreped paper sheet of FIG. 17, taken looking in the cross-machine direction along line 18-18 in FIG. 17.

FIG. l9 is a plan view photograph, enlarged about 6 times actual size, of a paper sheet such as is shown in FIGS. 17 and 18 after creping. The long axis of the impressions visible after creping is oriented generally in the cross-machine direction, while the overall surface of the paper exhibits a diamond-shaped pattern characteristic of paper sheets made in accordance with the present invention.

FIG. 20 is an illustration of an enlarged cross-section view of the creped paper sheet of FIG. 19, taken looking in the cross-machine direction along line 2020 in FIG. 19.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In describing preferred embodiments of the invention disclosed herein, specific terminology will be adhered to for the sake of clarity in referring to the features of the monofilament, polymeric fiber fabrics for use in papermaking and non-woven web manufacturing processes. The conventional face side of the semi-twill fabrics referred to herein refers to that side of the fabric which, according to the teachings of the prior art, would normally come in contact with the paper web, i.e., the sides of the semi-twill fabric which would, depending upon its particular condition, produce one of the imprint patterns illustrated in FIGS. 4, 8 or 12 (assuming it is a right-hand semi-twill fabric). In the aforementioned FIGS. the long axis of the dash impressions 9, where present, is aligned parallel to the crossmachine direction, while the long axis of the dot impressions 3, where present, is aligned parallel to the machine direction. The back side of the semi-twill fabrics referred to herein shall be defined as that side which would not normally contact the paper web according to the teachings of the prior art, i.e., the side of the semi-twill fabric which would, depending upon its particular condition, produce one of the imprint patterns illustrated in FIGS. 5, 9, 13, or 17 (assuming it is a right-hand semi-twill fabric). In the aforementioned figures, the long axis of the dash impressions 8 is aligned parallel to the machine direction, while the long axis of the dot impressions 10, where present, is aligned parallel to the cross-machine direction.

It should be noted that although a right-hand semitwill fabric is utilized for purposes of illustration throughout this specification, the benefits disclosed can also be obtained utilizing a left-hand semi-twill fabric, which is woven as a mirror image of a right-hand semitwill fabric.

FIG. 1 represents an enlarged plan view of aportion of a conventional right-hand, monofilament, polymeric fiber, semi-twill fabric as viewed from the back side. The semi-twill fabric illustrated in FIG. 1 has not been used on a paper machine nor has it been accorded any special abrading treatment. The warp monofilaments l are aligned parallel to the machine direction, while the woof or weft monofilaments 2 are aligned parallel to the cross-machine direction. In a preferred embodiment of the present invention, the imprinting fabric illustrated in FIG. 1 has about 20 to about 60 meshes per inch and is formed from monofilament polymeric fibers having diameters ranging from about 0.008 inches to about 0.025 inches. Both warp and woof monofilaments may, but need not necessarily be of the same diameter. FIGS. 2 and 3 are cross-sectional views of the semi-twill fabric illustrated in FIG. 1, taken looking respectively in the cross-machine and machine directions. The knuckles formed at the cross-over points of the warp filaments 1 and the woof filaments 2 are not coplanar on either the face or the back side of the fabric. As can be seen in FIGS. 2 and 3, the warp filaments l are at a higher relative elevation than the woof filaments 2 on both sides of the fabric. This is termed, for purposes of this specification, a warp-high condition of the fabric.

FIG. 4 is a simplified illustration of the knuckle imprint pattern which would result if a semitwill fabric such as is illustrated in FIGS. 1 through 3 were installed so that the conventional face side of the fabric were utilized to imprint an uncreped paper web produced in accordance with the teachings of U.S. Pat. No. 3,301,746 issued to Sanford et al. on Jan. 31, 1967, said patent being incorporated herein by reference. The dot impressions 3 visible on the surface of such an uncreped paper sheet after imprinting form a pattern corresponding to the knuckles 4 of the warp filaments 1 on the conventional face side of the fabric. Since the dot impressions 3 are formed by the warp filaments l, the long axis of the dot impressions is aligned parallel to the machine direction. The knuckles 7 formed by the woof filaments 2 on the conventional face side of the fabric do not form a corresponding impression in the uncompacted paper web due to the fact that they are at a lower relative elevation than the warp filament knuckles 4.

FIG. illustrates the knuckle imprint pattern which would result if an uncompacted paper web produced in accordance with the teachings of U.S. Pat. No.

3,301,746 were imprinted utilizing the back side of an imprinting fabric such as is illustrated in FIGS. 1 through 3. Because the warp filaments 1 are at a higher relative elevation than the woof filaments 2 on the back side of the fabric, only the peaks of the knuckles 5 formed by the warp filaments are impressed into the paper web during the imprinting process. Since the warp filaments 1 run in the machine direction, the resulting pattern consists of a series of relatively long dash impressions 8, wherein the long axis of the impressions is aligned parallel to the machine direction.

The imprint pattern illustrated in FIG. 5 differs from the imprint pattern illustrated in FIG. 4 in two important respects. First, since each warp filament 1 passes over two woof filaments 2 on the back side ofthe semitwill fabric as compared to only one woof filament 2 on the face side of the fabric, the length of the impressions is approximately twice as great when the web is imprinted with the back side of the fabric. Secondly, when a paper web imprinted with the pattern illustrated in FIG. 5 is removed from the drying drum by means of a conventional doctor blade, a diamond-shaped pattern is imparted to the surface of the paper, whereas when a paper web imprinted with the pattern illustrated in FIG. 4 is removed from the drying drum by means of a conventional doctor blade, a regulated creping pattern results in which the crepe ridges are substantially unbroken across the width of the sheet. This characteristic difference in finished product appearsto bedue to the fact that the web illlustrated in FIG. 4 is adhered to the dryer drum only at interrupted intervals, i.e., by the dot impressions 3, which impressions are not sufficiently long to overlap each other in the machine direction. The paper web illustrated in FIG. 5, on the other hand, is adhered to the dryer drum in a continuous fashion, i.e., by the dash impressions 8, which impressions are sufficiently long to overlap each other in the machine direction. 1

Based on the teachings of the prior art, and particularly on U.S. Pat. No. 3,473,576 issued to Amneus on Oct. 21, 1969, said patent being incorporated herein by reference, it is recognized that smooth web transfers and maximum drying effectiveness are not realized with fabrics having rough or inconsistent web contacting surfaces. Smooth web transfers are particularly desirable where, as in the case of the papermaking process disclosed in U.S. Pat. No. 3,301,746, the imprinting fabric is of product characteristic importance. It has, therefore, been found desirable to utilize imprinting fabrics having uniform knuckle heights and minimum free or interstitial area on the side of the fabric contacting the uncompacted paper web. Because such imprinting fabrics are subjected to elevated temperatures during use, it has also been found desirable to di mensionally heat stabilize such fabrics prior to use to prevent warpage.

It is important to note that due to the symmetry of a plain weave fabric, uniform knuckle heights and minimum free area achieved simultaneously on both sides of the fabric when the fabric is subjected to a heat treatment process such as that disclosed in U.S. Pat. No. 3,473,576. This is not the case with a semi-twill weave fabric. If a monofilament, polymeric fiber, semitwill fabric is subjected to a heat treatment process such as that disclosed in U.S. Pat. No. 3,473,576, the knuckles 4 and 7 on the conventional face side of the fabric will become coplanar before the knuckles 5 and 6 on the back side of the fabric. In order for the knuck- 1 1 les 5 and 6 on the back side of the fabric to reach uniform heights, the fabric must be subjected to further heat treatment; The additional heat treatment in turn causes the heights of the knuckles 4 and 7 on the conventional face side of the semi-twill fabric to again become non-uniform.

Therefore, the initial warp filament spacing and caliper of a semi-twill fabric necessary to produce minimum free area and uniform knuckle heights on the back side of the fabric after heat treatment is determined experimentally by trial and error.

In a preferred embodiment of the present invention, a monofilament, polymeric fiber, semi-twill fabric is prepared'by selecting warp monofilaments having a relatively high heat-induced shrinkage potential in the range of about 10 percent to about 30 percent, preferably about'l6 percent. After selecting and spacing the warp monofilaments, polymeric woof monofilaments are selected which have a relatively low heat-induced shrinkage potential in the range of about 2 percent to about 8 percent, preferably about 4 percent. The heat shrinkage treatment takes advantage of the aforementioned shrinkage characteristics of the warp and woof monofilaments. The heat shrinkage treatment comprises subjecting the initially woven fabric to a series of heat applications as it is stretched and secured at its ends in the lengthwise or warp direction, while it is free to shrink in the woof direction.

The heat shrinkage treatment is conveniently applied to the initially woven semi twill fabric while the fabric is mounted as an endless belt on a finishing table such as those conventionally used in finishing metal Fourdrinier wires. A conventional wire finishing table consists of two adjustable rolls for supporting, tensioning and driving the wire or fabric to be finished as an endless belt. The heat shrinkage can be induced conveniently by an infrared source mounted as a bank above and across the initially woven fabric. The infrared source heats areas of the initially woven fabric as the fabric slowly revolves on the rolls of the wire finishing table. Heat is applied to the fabric in successive treatments of about 5 seconds to about 40 seconds, preferably about seconds, per treatment. The fabric temperatures during the successive applications of heat approach gradually the softening point of the selected monofilament polymeric fibers. Multiple passes are used to avoid sudden shrinkage which induces fabric wrinkles. Successive heat treatments are repeated until the knuckle heights on the back side of the fabric reach uniformity, which condition should also correspond to minimum free or interstitial area if the initial warp filament spacing and caliper of the fabric have been properly determined. A semi-twill fabric which has been subjected to the aforementioned heat treatment process, although not locked-up as in the case of a plain weave fabric subjected to such a heat treatment process, is dimensionally heat stable at the temperatures encountered in the web imprinting process disclosed in U.S. Pat. No. 3,301,746. 3,301,746.

The temperature of the fibers in the successive heat treating passes is increased to a maximum temperature immediately below the softening point of the selected fibers. For example, the heat treating temperature used with Treviera fibers is about 360 to about 400F, preferably about 375F. For dimensional heat stability in use as an imprinting fabric is accordance with the teachings of US. Pat. No. 3,301,746, a sufficient number of successive heating treatments or passes are employed to insure that the monofilament polymeric fibers making up the fabric structure have been at the highest heat treating temperature for a total time of about 15 to about seconds.

Contrary to expectation, a weaving procedure wherein polymeric warp and woof monofilaments are merely woven as tightly as possible to insure a minimum free area will not result in a fabric with uniform knuckle heights after heat treating or use in web drying systems. Polymeric fibers in general exhibit heat shrinkage, and if such a tight weaving procedure involving initial minimum spacing in both polymeric warp and woof monofilaments is attempted, the resulting heat treated and heat stabilized fabric will exhibit non-uniform knuckle heights. Therefore, in a preferred embodiment of the present invention, an initial warp filament spacing in the loom and an initial caliper of the semi-twill fabric are determined experimentally by trial and error to take into account the heat-induced shrinkage which occurs during the above described dimensional heat stabilization process.

FIGS. 6 and 7 are enlarged cross-sectional views of a monofilament, polymeric fiber, semi-twill fabric such as is illustrated in FIGS. 1 through 3 after a heat treat ment process such as that described above has been initiated. FIG. 6 is taken looking in the cross-machine direction at a point corresponding to line 2-2 in FIG. I, while FIG. 7 is taken looking in the machine direction at a point corresponding to line 33 in FIG. 1. FIGS. 6 and 7 represent an intermediate condition of the fabric which occurs during the heat treatment process, prior to achieving uniform knuckle heights and minimum free area on the back side of the fabric. FIG. 6 represents the condition which results when the warp filaments I tend to draw themselves closer to a straight line due to the heat induced shrinkage. The tendency of the warp filaments 1 to assume a lower total amplitude, due to the heat-induced shrinkage, forces the woof monofilaments 2 on the conventional face side of the fabric downwardly and the woof monofilaments 2 on the back side of the fabric upwardly since the ends of the woof monofilaments are not restrained. This is more clearly illustrated in FIG. 7, wherein the Woof monofilaments 2 tend to wrap themselves more completely about the warp monofilaments 1. As a result, the knuckles 7 formed by the woof monofilaments 2 become coplanar with the knuckles 4 formed by the warp monofilaments 1 located on the conventional face side of the fabric. It should be noted that, at this particular point, the knuckles 5 formed by the warp monofilaments 1 remain at a higher relative elevation than the knuckles 6 formed by the woof monofilaments 2 on the back side of the fabric.

FIG. 8 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet produced in accordance with the teachings of US. Pat. No. 3,301,746, which uncreped paper sheet has been imprinted utilizing the conventional face side of a monofilament, polymeric fiber, semi-twill fabric such as is illustrated in FIGS. 6 and 7. The knuckle imprint pattern is similar to that shown in FIG. 4 wherein the dot impressions 3 formed by the knuckles 4 of the warp monofilaments 1 on the conventional face side of the fabric are illustrated, but the dash impressions 9 formed by the knuckles 7 of the woof monofilaments 2 are also present. Because the woof monofilaments 2 are aligned parallel to the cross-machine direction, the long axis of the dash impressions 9 is also aligned paral- 13 lel to the cross-machine direction.

FIG. 9 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet produced in accordance with the teachings of US Pat. No. 3,301,746, which uncreped paper sheet has been imprinted utilizing the back side of a semi-twill fabric such as is illustrated in FIGS. 6 and 7. As in FIG. 5, the long axis of the dash impressions 8 formed by the knuckles of the warp monofilaments l is aligned parallel to the machine direction.

As with paper sheets imprinted with the pattern illustrated in FIG. 4, paper sheets utilizing the imprinting pattern illustrated in FIG. 8 exhibit a basic regularity of creping wherein the crepe ridges extend substantially uninterrupted across the entire width of the sheet. Addition of the dash impressions 9 to the imprinting pattern does not alter the fact that the imprinted paper sheet is adhered to the dryer drum only at interrupted intervals corresponding to the spacing, in the machine direction, of the dot impressions 3. Paper sheets imprinted with the pattern illustrated in FIG. 9, on the other hand, exhibit a diamond-shaped pattern characteristic of paper sheets made in accordance with the present invention when doctored from the dryer drum.

In order to obtain uniform knuckle heights and minimum free area on the back side of a semi-twill fabric such as is illustrated in FIGS. 6 and 7, as is desired in a preferred embodiment of the present invention, the heat treatment process is continued until a condition similar to that illustrated in FIGS. 10 and 11 is achieved. FIG. 10 is taken looking in the cross-machine direction at a point corresponding to line 2-2 in FIG. 1, while FIG. 11 is taken looking in the machine direction at a point corresponding to line 3-3 in FIG. 1. Heat-induced shrinkage of the warp monofilaments l, as shown in FIG. 10, has produced a lower total amplitude causing the woof monofilaments 2 on the back side of the fabric to move upwardly and the woof monofilaments 2 on the conventional face side of the fabric to move downwardly. As can be seen in FIG. 11, the woof monofilaments 2 which, unlike the warp monofilaments l, are not subjected to tension tend to wrap themselves more completely about the warp monofilaments 1 located on the conventional face side of the fabric. Simultaneously, the woof monofilaments 2 tend to belly" or gradually wrap themselves about the two adjacent warp monofilaments 1 located on the back side of the fabric. As a result, the heights of the warp monofilament knuckles 5 on the back side of the fabric and the woof monofilament knuckles 6 on the back side of the fabric become uniform, while the heights of the woof monofilament knuckles 7 on the conventional face side of the fabric and the warp monofilament knuckles 4 on the conventional face side of the fabric become nonuniform. If the initial warp filament spacing in the loom and the initial caliper or thickness of the semi-twill fabric have been properly determined to take into account the heat-induced shrinkage, the condition illustrated in FIGS. 10 and 1] should result, i.e., a dimensionally heat stabilized semitwill fabric having uniform knuckle heights as well as minimum free area on its back side.

FIG. 12 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet made in accordance with the teachings of US. Pat. No. 3,301 ,746, which uncreped paper sheet has been imprinted utilizing the conventional face side of a semitwill fabric such as is illustrated in FIGS. 10 and 11.

The imprinting pattern is basically similar to that shown in FIG. 8, but the dot impressions 3 formed by the warp monofilament knuckles 4 on the conventional face side of the fabric are no longer present due to the fact that the warp monofilament knuckles 4 are at a lower relative elevation than the woof monofilament knuckles 7 on the conventional face side of the fabric. Paper sheets imprinted with the pattern illustrated in FIG. 12 exhibit properties substantially similar to sheets imprinted with the patterns shown in FIGS. 4 and 8 after creping.

FIG. 13 is a simplified illustration of an enlarged partial plan view of an uncreped paper sheet produced in accordance with the teachings of US. Pat. No. 3,301,746, which uncreped paper sheet has been imprinted utilizing the back side of a semi-twill fabric such as is illustrated in FIGS. 10 and 11. The dash impressions 8 formed by the warp filament knuckles 5 on the back side of the fabric are essentially the same as those illustrated in FIG. 8, but the dot impressions 10 formed by the woof monofilament knuckles 6 on the back side of the fabric are also present due to the fact that the warp filament knuckles 5 and the woof filament knuckles 6 on the back side of the fabric areof uniform height. Paper sheets produced utilizing the back side of a semitwill fabric such as is illustrated in FIGS. 10 and ll.for imprinting purposes exhibit a diamond-shaped surface appearance aftercreping, which surface appearance is characteristic of papersheets made in accordance with applicants invention. As the knuckle imprint area on the back side of such a monofilament, polymer fiber, semi-twill fabric is increased, the diamond-shaped pattern becomes more pronounced.

Applicant has discovered that increasing the knuckle imprint area on the back side of such a fabric also pro duces certain unexpected improvements in finished sheet characteristics. These unexpected improvements take the form of greater cross-directional stretch, as well as improved softness, surface feel and drape. Increasing the knuckle imprint area on the convenional face side of a similar monofilament, polymeric fiber, semi-twill imprinting fabric does not, however, yield similar improvements in finished sheet characteristics. This is likewise true of plain weave imprinting fabrics. Applicant has thus learned unexpectedly that the above mentioned improvements in sheet characteristics are uniquely achievable by increasing the knuckle imprint area on the back side of a conventional monofilament, polymeric fiber, semi-twill imprinting fabric.

One method of increasing the knuckle imprint area of a monofilament, polymeric fiber fabric is disclosed in US. Pat. No. 3,573,164 issued to Friedberg et al. on Mar. 30, 1971, said patent being incorporated herein by reference, wherein the knuckle surfaces are abraded with a fine abrasive medium to improve web transfer, web drying, web product characteristics and general machine operation. In a preferred embodiment of the present invention, the monofilament, polymeric fiber, semi-twill imprinting fabric to be abraded is brought to the condition illustrated in FIGS. 10 and 11, i.e., uniform knuckle heights and minimum free area on its back side, prior to initiating any abrading treatment. Although the abrasion treatment disclosed in the aforementioned Friedberg et al. patent will produce uniform knuckle heights on a fabric which does not initially have uniform knuckle heights, it is most desirable, in a preferred embodiment of the present invention, to utilize a fabric initially having uniform knuckle heights on the side to be treated to minimize the possibility of abrading completely through one or more monofilaments during the abrading process. Therefore, the back side of a fabric such as is shown in FIGS. and 1 1 can undergo a more extensive abrading process, thus producing a greater increase in knuckle imprint area than is permissible with a fabric initially having non-uniform knuckle heights on the side to be treated.

As mentioned earlier in this specification, it has been found desirable that monofilament, polymeric fiber fabrics be dimensionally heat stabilized prior to use. Failure to do so can cause warpage after the fabric has been placed in service and subjected to elevated temperatures. Thus, to realize the full benefits to be obtained by the abrading process, it is most desirable, in a preferred embodiment of the present invention, that the semi-twill fabric be dimensionally heat stabilized in accordance with the procedures described in this specification prior to initiating the abrading treatment.

In accordance with the teachings of the aforementioned Friedberg et al. patent, the back side of a monofilament, polymeric fiber, semi-twill imprinting fabric, in a preferred embodiment of the present invention, is subjected to a treatment wherein the knuckle surfaces of the fabric are abraded using either a wet or dry sandpaper having an effective abrasive grain size of about 300 mesh to about 500 mesh as an abrasive medium. The abrasive media can be mounted on drums for rotative application to the fabric knuckle surfaces. The abrading process can be performed while continuously showering the fabric with water or other cleansing and lubricating fluid, for example light oil, to remove abraded particles and facilitate the polishing operation.

In a preferred embodiment of the present invention, a total knuckle imprint area of about 20 percent to about 50 percent of the total fabric surface area, as measured in the plane of the knuckles, is developed on the treated surface. Increasing the knuckle imprint area beyond the 50 percent level greatly increases the danger of abrading completely through particular monofilaments and is also likely to have a detrimental effect on the fabric life.

In yet another preferred embodiment of the present invention, it is desirable to form a smooth and polished surface on the knuckles on the back side of the monofilament, polymeric fiber semi-twillfabric. To this end, the above described abrading operation can be conducted in several stages. For example, the initial abrasion can be carried out with an abrasive medium having an effective abrasive grain size of about 300 mesh, and this initial abrading operation can be followed by an abrasive polishing treatment using a water lubricated wet sandpaper having an effective abrasive grain size of about 500 mesh. Polishing abrasives such as talc, rouge and crocus cloth can also be used to further polish the knuckle surfaces.

FIGS. 14 and are enlarged cross-sectional views of a monofilament, polymeric fiber, semitwill fabric such as is illustrated in FIGS. 10 and 11 after the back side of the fabric has been abraded to increase its knuckle imprint area to between about percent and about 50 percent of the total fabric surface area, as measured in the plane of the knuckles. FIG. 16 is a plan view of an enlarged portion of the fabric illustrated in FIGS. 14 and 15, as viewed from the back side of the fabric. The fabric illustrated in FIGS. 14 through 16 represents a preferred embodiment of the present invention,

wherein uniform knuckle heights and minimum free area were achieved on the back side of the fabric prior to initiating the abrading process. An inherent advantage associated with obtaining uniform knuckle heights and minimum free area prior to initiating the abrading treatment is in the uniform consistency of the knuckle imprint pattern which results after the abrading process has been completed. This latter feature is most clearly illustrated in FIG. 16.

FIGS. 14 and 15, taken looking in the cross-machine and machine directions respectively, illustrate the fabric profile which is presented to an uncompacted paper web when the fabric is utilized for imprinting purposes in accordance with the teachings of US. Pat. No. 3,301,746. The warp filament knuckles 5 and the woof filament knuckles 6 as shown in FIGS. 10 and 11 have been abraded to form the plateau-like warp filament knuckles 5 and Woof filament knuckles 6 illustrated in FIGS. 14 and 15. In addition to improving web transfer and web drying characteristics, the plateau-like knuckle surfaces 5' and 6' impress an uncompacted paper web to a uniform depth, thus producing a more distinct imprint pattern.

The moist paper web carried on an imprinting fabric of the present invention can be thermally pre-dryed by means of passing hot gases, for example air, through the moist paper web and the imprinting fabric. One suitable apparatus for pre-drying the moist paper web is disclosed in US. Pat. No. 3,303,576 issued to Sisson on Feb. 14, I967, which patent is incorporated herein by reference. Although the means by which thermal predrying is accomplished is not critical, it is critical that the relationship of the moist web to the imprinting fabric be maintained once established.

According to the teachings of US. Pat. No. 3,301,746, thermal pre-drying is used to effect a fiber consistency in the moist paper web from about 30 percent to about percent, preferably about 40 percent to about 80 percent. The aforementioned Sanford et al. patent further teaches that at fiber consistencies less than about 30 percent, the desirably balanced sheet characteristics of softness, bulk and absorbency suffer because the sheet and the fibers thereof are two moist, and yielding occures during the imprinting step. The aforementioned Sanford et al. patent also teaches that pre-drying to fiber consistencies above about 80 percent precludes the development of effective tensile strengths in the imprinted paper sheet.

Based on the Sanford et al. patent and the application of Gregory A. Bates, Ser. No. 452,610 filed Mar. 19, 1974 and entitled TRANSFER AND ADHERENCE OF RELATIVELY DRY PAPER WEB TO A ROTAT- ING CYLINDRICAL SURFACE, said application being commonly owned by the assignee of the present invention and incorporated herein by reference, it is now-known that fiber consistencies between about 30 percent and about 98 percent prior to transfer of the web to the drying drum are possible without adversely affecting the tensile strength of paper sheets thus produced. Fiber consistencies in the higher end of the range, i.e., above about 80 percent, are now known to be a function of the adhesive sprayed on the surface of the drying drum prior to web transfer, as explained in detail in the aforementioned application of Bates.

Imprinting the fabric knuckle pattern in the moist web by pressing the pre-dryed web against a relatively non-yielding surface, for example, an unheated steel roll or a Yankee dryer surface, while the pre-dryed web is yet carried on the imprinting fabric results in a paper sheet having impressed in its surface, to a depth of at least 30 percent of its machine glazed caliper the knuckle pattern of the imprinting fabric. Machine glazed claiper refers to the caliper of the paper sheet taken directly from the Yankee dryer, before creping. Thus, the knuckle surfaces and 6', illustrated in FIGS. 14 through 16 in a preferred embodiment of the present invention, are impressed to a uniform depth of at least 30 percent of the machine glazed caliper of the uncreped paper sheet.

The pressure required for the imprinting of the imprinting fabric pattern can be provided, in a preferred embodiment of the present invention, by one or more pressure rolls operating on the imprinting fabric to force the knuckles of the fabric into the surface of the pre-dryed web and to force the pre-dryed web surface under the knuckles against a Yankee dryer surface.

It should be understood that it is critical to the practice of the present invention that the imprinting step described above be the first substantial overall mechanical compaction step which the paper web has received during formation and pre-drying.

FIG. 17 is a photograph of an enlarged partial plan view of an uncreped paper sheet made in accordance with the teachings of US. Pat. No. 3,301,746, utilizing the back side of a semi-twill fabric such as is illustrated in FIGS. 14 through 16 to imprint the uncompacted paper web. The resulting knuckle imprint pattern is basically similar to that shown in FIG. 13. However, the dash impressions 8 formed by the warp filament knuckles 5' and the dot impressions formed by the woof filament knuckles 6' constitute a greater percentage of the sheets surface area due to the increase in the size of the fabric knuckles. In addition, the impressions 8 and 10 are more distinct due to the fact that they are of substantially uniform depth, having been produced by the plateau-like surfaces of the knuckles 5 and 6'.

FIG. 18 is an illustration of an enlarged cross-sectional view of the uncreped paper sheet of FIG. 17, taken looking in the cross-machine direction along line 18-48 in FIG. 17.

'FIG. 19 is a photograph of an enlarged partial plan view of a creped paper sheet made in accordance with the teachings of US. Pat. No. 3,301,746, utilizing the back side of a semi-twill fabric such as is illustrated in FIGS. 14 through 16 to imprint the uncompacted paper web prior to creping. The long axis of the impressions 11 visible after creping appears to be oriented generally in the cross-machine direction. Unlike paper sheets made in accordance with the teachings of the aforementioned Sanford et al. patent utilizing either a similarly prepared plain weave imprinting fabric or the conventional face side of a similarly prepared semi-twill imprinting fabric, the overall surface of the paper exhibits a diamond-shaped pattern rather than uniform unbroken creping ridges extending across the width of the sheet.

FIG. 20 is an illustration of an enlarged cross-sectional view of the paper sheet of FIG. 19, taken looking in the cross-machinc direction along line 2020 in FIG. 19. I

A finished paper sheet such as is illustrated in FIGS. 19 and 20, produced in accordance with the present invention, exhibits improvements in cross-directional stretch, softness, surface feel and drape which are not achievable by the paper manufacturing process disclosed in US. Pat. No. 3,301,746 when a similarly precharacteristics, does not produce the improvements in cross-directional stretch, softness, surface feel and drape which are realized by increasing the knuckle imprint area on the back side of a semi-twill imprinting fabric.

From the foregoing general and specific description of the present process, it is apparent that the critical procedures to be carried out are the formation of an uncompacted paper web at a specified range of fiber consistency and the imprinting thereof by the knuckles on the back side of a monofilament, polymeric fiber, semi-twill imprinting fabric, said fabric having a knuckle imprint area constituting about 20 percent to about 50 percent of the total surface area on the back side of the fabric, as measured in the plane of the knuckles. The formation of the paper web and the final drying techniques together with the pre-drying imprinting and creping procedures can. be varied by one skilled in the art to produce distinctive papers for various uses while remaining within the scope of this invention.

By the foregoing procedures, creped paper sheets exhibiting a diamond-shaped surface appearance, composed substantially of cellulosic fibers, having basic weights of from about 5 to about 40 pounds per 3000 square feet, and exhibiting a repeating pattern of discrete impressed areas are produced.

In order to demonstrate the improvements characteristic of finished product made in accordance with applicants invention, a series of test runs were made to compare the characteristics of paper sheets made in accordance with the teachings of US. Pat. No. 3,301,746, utilizing different sides of a monofilament, polymeric fiber, semi-twill fabric. Paper machine conditions, with the exception of the imprinting fabric, were maintained constant for the entire series of tests.

Furnish comprised of a 50 percent softwood kraft and a 50 percent hardwood sulfite stock was utilized throughout the entire series of tests.

An adhesive coat was applied to the Yankee dryer surface by utilizing a wire glue roll of approximately 40 mesh turning at a lineal speed of approximately 9 feet per minute at its periphery in an open glue pot and then spraying the glue picked up on the wire mesh glue roll onto the surface of the Yankee dryer drum by means of a series of air jets located interiorly of the glue roll and operating continuously at an air pressure of p.s.i.g. The glue utilized was purchased under the specification Peter Cooper IX from the Peter Cooper Corporation of Gowanda, New York. The mixture, as applied, contained 1 part glue and 99 parts water. The pre-dryed and imprinted web was caused to part from the imprinting fabric at the pressure nip exit and adhere to the Yankee dryer surface by means of the adhesive coat described above.

The dry creped sheet was removed from the Yankee dryer by means of a conventional doctor blade so that the finished product had 12 percent stretch as crepe folds.

Two separate monofilament, polymeric fiber, semitwill fabrics were utilized during the test runs. The fabrics were both 31 (machine direction) by 28 (crossmachine direction) mesh utilizing warp and woof 19 monofilaments having a diameter of 0.45 mm. (about 0.018 inches). One of the fabrics was woven so as to present its back side as a web contacting surface and the other was woven so as to present its conventional face side as a web contacting surface. Both of the fabrics, as received, were in a configuration similar to that illustrated in FIGS. and 11, Le, the heights of the warp filament knuckles 5 and the woof filament knuckles 6 on the back side of each fabric were approximately equal, while the warp filament knuckles 4 were at a lower relative elevation than the woof filament knuckles 7 on the conventional face side of each fabric.

In order to isolate the effect of the imprinting fabrics on finished sheet characteristics, the fabrics were installed successively on the same paper machine in the as-received condition, and paper sheets were produced in accordance with the teachings of US. Pat. No. 3,301,746.

The fabric woven so as to present its back side as a web contacting surface was found to have an initial knuckle imprint area of about 21.2 percent in the asreceived condition, while the fabric woven so as to present its conventional face side as a web contacting surface was found to have a knuckle imprint area of about 23.4 percent in the as-received condition.

Data taken from paper samples made utilizing the imprinting fabric having its back side in contact with the uncompacted paper web is reported hereinbelow under Example I. Data taken from paper samples made utilizing the imprinting fabric having its conventional face side in contact with the uncompacted paper web is reported hereinbelow under Example II. With the exception of the imprinting fabrics, the paper machine conditions were unchanged between Examples I and II.

To illustrate the effect of increasing the knuckle imprint area on the web contacting side of the imprinting fabrics, each fabric was abraded in accordance with the teachings of US. Pat. No. 3,573,164. The knuckle imprint area on the fabric utilizing its back side as a web contacting surface was increased from approximately 21.2 percent to approximately 28.4 percent, while the knuckle imprint area of the fabric utilizing its conventional face side as a web contacting surface was increased from approximately 23.4 percent to approximately 34.1 percent. The tests were repeated keeping all paper machine conditions, other than the increased knuckle imprint area of the fabrics, unchanged. The results of tests performed on sample paper sheets taken during each run are tabulated hereinbelow under Examples Ill and IV. The data set forth in Example III is taken from sample sheets made utilizing the semi-twill imprinting fabric which presented its back side to the uncompacted paper web, while the data set forth in Example IV is taken from sample sheets made utilizing the semi-twill fabric which presented its conventional face side to the uncompacted paper web.

Finally, the knuckle imprint area of each fabric was further increased in accordance with the teachings of US. Pat. No. 3,573,164 until the fabric utilizing its back side as a web contacting surface achieved a total knuckle imprint area of 37.3 percent, while the fabric utilizing its conventional face side as a web contacting surface achieved a total knuckle imprint area of 40.0 percent. The tests were repeated keeping all paper machine conditions, other than the knuckle imprint area of the fabrics, unchanged. The results of tests performed on sample paper sheets taken during each run are tabulated hereinbelow under Examples V and VI.

20 Data set forth in Example V is taken from paper sheets made utilizing the semi-twill fabric which presented its back side to the uncompacted paper web, while data set forth in Example VI is taken from paper sheets made utilizing the semi-twill fabric which presented its conventional face side to the uncompacted paper web.

The caliper of a paper sheet at grams per square inch, as tabulated in the Examples hereinbelow, is the thickness of that sheet when subjected to a compressive load of 80 grams per square inch.

The tensile strengths in the machine direction (MD) and cross-machine direction (CD), as tabulated in the Examples hereinbelow, are reported as the force in grams that a 1 inch wide sample with a 4 inch span between the tensile tester clamps, cut in the MD or CD direction, can withstand before breaking, as measured on a standard Thwing-Albert Tensile Tester such as is available from the Thwing-Albert Instrument Company of Philadelphia, Pennsylvania.

The percentage stretch data tabulated in the Examples hereinbelow was determined concurrently with the determination of MD and CD tensile strengths as described above.

A Thwing-Albert I-Iandle-O-Meter, catalogue num-. ber 21 1-3, such as is available from the Thwing-Albert Instrument Company of Philadelphia, Pennsylvania, was used to measure a combination of stiffness and sliding friction of the paper samples. A high Handle-O- Meter or I-I-O-M reading indicates a lack of softness and is, therefore, undesirable. A lower I-I-O-M reading indicates a softer sheet. Two 4 /2 inch by 4 /2 inch paper samples were placed side by side over the 0.25 inch wide Handle-O-Meter slot located beneath the blade of the unit. To determine the machine direction Handle- O-Meter reading of the sheets, the machine direction of the paper samples was aligned parallel to the Handle- O-Meter blade. To determine the cross-machine direc tion l-Iandle-O-Meter reading, the machine direction of the sample sheets was aligned perpendicular to the blade of the Handle-O-Meter. Readings taken directly from the standard 50 micro-ampere meter mounted on the I-Iandle-O-Meter are reported in the Examples hereinbelow.

In order to quantify sheet properties relating to surface feel and drape, resort was had to the principles of textile testing. Fabric handle, asits name implies, is concerned with the feel of the material and so depends on the sense of touch. When the handle of a fabric is judged, the sensations of stiffness or'limpness, hardness of softness, and roughness or smoothness are all made use of. Drape has a rather different meaning and very broadly is the ability of a fabric to assume a graceful ap pearance in use. Experience in the textile industry has shown that fabric stiffness is a key factor in the study of handle and drape.

One instrument devised by the textile industry to measure stiffness is the Shirley Stiffness Tester. In order to compare the drape and surface feel properties of paper samples made utilizing different sides of a semi-twill imprinting'fabric, a Shirley Stiffness Tester was constructed to determine the bending length of the paper samples, and hence to calculate values for flexural rigidity and bending modulus.

The Shirley Stiffness Tester is described in ASTM Standard Method No. 1388. The horizontal platform of the instrument is supported by two side pieces made of plastic. These side pieces have engraved on them index lines at the standard angle of deflection of 41 /2. At-

21 tached to the instrument is a mirror which enables the operator to view both index lines from a convenient position. The scale of the instrument is graduated in centimeters. The scale may be used as a template for cutting the specimens to size.

To carry out a test, a rectangular strip ofpaper, 6 inches by 1 inch, is cut to the same size as the scale and then both scale and specimen are transferred to the platform with the specimen underneath.- Both are slowly pushed forward. The strip of paper will commence to droop over the edge of the platform as the scale and specimen are advanced. Movement of the scale and the specimen is continued until the tip of the specimen viewed in the mirror cuts both of the index lines. The amount of overhang, I, can immediately be read off from the scale mark opposite a zero line engraved on the side of the platform.

Due to the fact that paper assumes a permanent set after being subjected to such a stiffness test, four individual specimens were utilized to test the stiffness of 20 the paper along a given axis, and an average value for the particular axis was then calculated. Samples were cut both on and across the cross-machine direction (CD) axis, on and across the CD+30 axis, and on and across the CD+135 axis. From the data collected both on and perpendicular to each of three aforementioned axes, an average overhang value, I, was calculated for theparticular paper sample.

The bending length, 0, for purposes of these tests, shall be defined as the length of paper that will bend under its own weight to a definite extent. it is a measure of the stiffness that determines draping quality. The calculation is as follows: i

c f cm. f(6) wheref() [cos /2 6+ 8 tan 0], and f the average overhang value of the particular paper sample as determined above.

In the case of the Shirley Stiffness Tester, the angle 0 41 V2", at which angle f(6) orf(41 /2) 0.5. Therefore, the above calculation simplifies to:

c=f X (0.5) cm.

Flexural rigidity, G, is a measure of stiffness associated with handle. The calculation of flexural rigidity, G, in the present instance is as follows:

The bending modulus, q, as reported in the Examples hereinbelow, is independent of the dimensions of the strip tested and may be regarded as .the intrinsic stiffness of the material. Therefore, this value may be used to compare the stiffness of materials having different 10 thicknesses. For its calculation, the thickness or caliper of the paper sample must be measured at a pressure of 1 pound per square inch.

The bending modulus, q, is; then given by:

q 732 X G I- g kg./sq.cm., where G is the flexural rigidity of the particular paper sample as determined above, expressed in mg. cm., and g is the thickness or caliper of the particular paper sample, expressed in mils, when subjected to a pressure of 1 pound per square inch.

The results of tests performed on sample paper sheets produced during the runs described above are reported in the Examples hereinbelow :in terms of bending mod ulus, q, which has relevance with respect to both drape and surface feel. A lower bending modulus corresponds to increased drape, and hence to improved surface feel.

The knuckle imprint areas referred to in the Examples hereinbelow were determined by making an impression with pressure sensitive paper in each of four areas on the web contacting surface of the imprinting 3O fabric utilized in the particular Example. Enlarged photographs were taken of each of the four impressions, and a unit-cell of knuckles, i.e., one repeating pattern of knuckles, was enclosed in each photograph. The total area of each enclosed unit-cell and the total area of the knuckles inside each such unit-cell'we re then 40 The Examples below compare the finished sheet properties of paper samples produced in accordance with the present invention with the sheet properties of paper samples produced utilizing the conventional face side of a similar imprinting fabric at various stages of fabric treatment.

EXAMPLE 1 Back side of imprinting fabric contacting web Cal Basis Sample no. ipcr at Knuckle weight Bending (for indentigm/ imprint pounds] Tensile Tensile Handle Handle- Stretch Stretch Modulus fication pursq.in., area, 3,000 MD,gm./ CD,gm./ O-Meter O-Meter MD. CD. q",kg./ poses only) inches percent sq.ft. in. in. MD CD "/1 71 sq.cm.

EXAMPLE 11 Conventional face side of imprinting fabric contacting web Cal- Basis Sample no.' iper at Knuckle weight Bending (for indenti- 80 gm/ imprint pounds/ Tensile Tensile Handle- Handle- Stretch Stretch Modulus fication pursq.in., area, 3,000 MD,gm./ CD,gm./ O-Meter O-Meter MD, CD, q,kg./ poses only) inches percent sq.ft. in. in. MD CD sq.cm.

EXAMPLE 111 Back side of imprinting fabric contacting web Cal- Basis Sample no. iper at Knuckle weight Bending (for indenti- 80 gm/ imprint pounds/ Tensile Tensile Handle- Handle- Stretch Stretch Modulus fication pursq.in.. area, 3,000 MD,gm./ CD,gm./ O-Meter OMeter MD. CD, q,kg./ poses only). inches percent sq.ft. in. in. MD CD 7: sq.cm.

EXAMPLE lV Conventional face side of imprinting fabric contacting web Cal- Basis Sample no. iper at Knuckle weight Bending 1 (for indenti- 80 gm/ imprint pounds/ Tensile Tensile Handle Handle- Stretch Stretch Modulus fication pursq.in., area, 3,000 MD,gm./ CD,gm./ O-Meter O-Meter MD, CD. q".kg./ poses only) inches percent sq.ft. in. in. MD CD sq.cm.

EXAMPLE V Back side of imprinting fabric contacting web Cal- Basis Sample no. iper at Knuckle weight Bending (for indenti- 80 gm/ imprint pounds/ Tensile Tensile Handle- Handle- Stretch Stretch Modulus fication pursq.in., area. 3,000 MD,gm./ CD.gm./ O Metcr O-Meter MD, CD, q",kg./ poses only) inches percent sq.ft. in. in. MD CD "/1 7r sq cm.

EXAMPLE V1 Conventional face side of imprinting fabric contacting weh Cal- 7 Basis Sample no. iper at Knuckle weight Bending (for indenti- 80 gm/ imprint pounds/ Tensile Tensile Handle- Handle- Stretch Stretch Modulus fication pursq.in., area. 3,000 MD.gm./ CD.gm./ O-Mcter O-Mctcr MD, CD. q",kg./ poses only) inches percent sq.ft. in. in. MD CD /1 sq.cm.

EXAMPLE Vl Continued Conventional face side of imprinting fabric contacting web Cal- Basis Sample no. iper at Knuckle weight Bending (for indenti- 80 gm/ imprint pounds} Tensile Tensile Handle- Handle- Stretch Stretch Modulus fication pursq.in., area, 3,000 MD,gm./ CD,gm./ O-Meter O-Meter MD. CD, q",kg./ poses only) inches percent sq.ft. in. in. MD CD sq.cm.

4 0.009] 40.0 l4.5 304 2l3 12.25 2.0 23.0 2.0 l5.66

The data presented in the Examples above clearly show the advantages of the present invention in producing a paper sheet characterized by having significantly improved cross-directional stretch, softness, surface feel and drape.

It is to be understood that the forms of the invention herein illustrated and described are to be taken as preferred embodiments. Various changes or omissions may be made in the weaving process, the heat treating process, or in the process for increasing the knuckle imprint area of the fabric without departing from the spirit or scope of the invention as defined in the attached claims.

Having thus defined and described the invention, what is claimed is:

1. A process for the manufacture of a soft, bulky and absorbent paper sheet which comprises the steps of:

a. forming an uncompacted paper web having a uniform basis weight of about 5 to about 40 pounds per 3000 square feet,

b. supporting said uncompacted paper web on the back side of a semi-twill imprinting fabric having about to about 60 meshes per inch, the knuckle imprint area on the back side of said fabric consti-.

tuting between about 20 and about 50 percent of the total fabric surface area, as measured in the plane of the knuckles, said imprinting fabric being formed from filaments having a diameter of about 0.008 to about 0.025 inches,

c. thermally pre-drying said uncompacted paper web to a fiber consistency between about 30 and about 98 percent,

d. imprinting a dot-dash knuckle pattern with said semi-twill imprinting fabric such that the long axis of the dash impressions in said pattern is aligned parallel to the machine direction .of the pre-dryed, uncompacted paper web, and

e. final drying and creping the paper sheet so formed.

2. The process for the manufacture of a soft, bulky and absorbent paper sheet as described in claim 1 wherein the final drying of the paper sheet is performed on the imprinting fabric.

3. The process for the manufacture of a soft, bulky and absorbent paper sheet as described in claim 1 wherein the final drying of the paper sheet is performed on a Yankee dryer drum and the creping is performed by means of a doctor blade.

4. The process for the manufacture of a soft, bulky and absorbent paper sheet as described in claim 1 wherein the uncompacted paper web formed in step (a) is molded to conform to the pattern of the imprinting fabric prior to thermally pre-drying the uncompacted paper web in step (c).

5. A process for the manufacture of a soft, bulky and absorbent paper sheet which comprises the steps of: a. forming an uncompacted paper web having a uniform basis weight of about 9 to about 25 pounds per 3000 square feet,

b. supporting said paper web on the back side of a semi-twill imprinting fabric having about 20 to about 60 meshes per inch, the knuckle imprint area on the back side of said fabric constituting between about 20 and about 50 percent of the total fabric surface area, as measured in the plane of the knuckles, said imprinting fabric being formed from filaments having a diameter of about 0.008 to about 0.025 inches,

0. thermally pre-drying said uncompacted paper web to a fiber consistency between about 40 and about 98 percent,

d. imprinting a dot-dash knuckle pattern with said semi-twill imprinting fabric such that the long axis of the dash impressions in said pattern is aligned parallel to the machine direction of the pre-dryed, uncompacted paper web, and

e. final drying and creping the paper sheet so formed by means of a Yankee dryer drum and a doctor blade.

6. The process for the manufacture of a soft, bulky and absorbent paper sheet as described in claim 5 5 wherein the uncompacted paper web formed in step (a) is molded to conform to the pattern of the imprinting fabric prior to thermally pre-drying the uncompacted web in step (c).

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO.

DATED INVENTOR(S) Column Column Column Column Column Column Column Column [SEAL] September 16,

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

1, line 42, "embodimen" should read, embodiment 1, line 61, "to" should read as 4, line 36, after "uniform" insertheights 16, line 43, "two" should read too 16, line 44, "oocures" should read ocours 18, line 29, "basic" should read basis 19, line 42, "of" should read on 20, line 50, "of" should read or Signed and Sealed this Eighth Day of February 1977 Arrest:

RUTH C. MASON Arresting Officer

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3159530 *23 Jun 19601 Dec 1964Kimberly Clark CoPapermaking machine
US3301746 *13 Apr 196431 Jan 1967Procter & GambleProcess for forming absorbent paper by imprinting a fabric knuckle pattern thereon prior to drying and paper thereof
US3473576 *14 Dec 196721 Oct 1969Procter & GambleWeaving polyester fiber fabrics
US3573164 *22 Aug 196730 Mar 1971Procter & GambleFabrics with improved web transfer characteristics
US3812000 *24 Jun 197121 May 1974Scott Paper CoSoft,absorbent,fibrous,sheet material formed by avoiding mechanical compression of the elastomer containing fiber furnished until the sheet is at least 80%dry
US3817827 *30 Mar 197218 Jun 1974Scott Paper CoSoft absorbent fibrous webs containing elastomeric bonding material and formed by creping and embossing
US3821068 *17 Oct 197228 Jun 1974Scott Paper CoSoft,absorbent,fibrous,sheet material formed by avoiding mechanical compression of the fiber furnish until the sheet is at least 80% dry
US3851681 *18 Apr 19733 Dec 1974Albany Int CorpWoven papermaking drainage fabric having four shed weave pattern and weft threads of alternating diameter
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3994771 *30 May 197530 Nov 1976The Procter & Gamble CompanyProcess for forming a layered paper web having improved bulk, tactile impression and absorbency and paper thereof
US4042740 *20 Sep 197416 Aug 1977Minnesota Mining And Manufacturing CompanyReinforced pillowed microfiber webs
US4103058 *15 Mar 197625 Jul 1978Minnesota Mining And Manufacturing CompanyPillowed web of blown microfibers
US4191609 *9 Mar 19794 Mar 1980The Procter & Gamble CompanySoft absorbent imprinted paper sheet and method of manufacture thereof
US4239065 *9 Mar 197916 Dec 1980The Procter & Gamble CompanyPapermachine clothing having a surface comprising a bilaterally staggered array of wicker-basket-like cavities
US4309246 *14 Aug 19785 Jan 1982Crown Zellerbach CorporationPapermaking apparatus and method
US4533437 *16 Nov 19826 Aug 1985Scott Paper CompanyPapermaking machine
US4612231 *24 Sep 198416 Sep 1986James River-Dixie Northern, Inc.Patterned dry laid fibrous web products of enhanced absorbency
US4671983 *12 Jun 19859 Jun 1987Marcal Paper Mills, Inc.Embossments for minimizing nesting in roll material
US4941239 *14 Feb 198917 Jul 1990Albany International CorporationMethod to reduce forming fabric edge curl
US4942077 *23 May 198917 Jul 1990Kimberly-Clark CorporationTissue webs having a regular pattern of densified areas
US5100512 *11 Sep 199031 Mar 1992The Mead CorporationDandy roll having a twill weave wiremark and related method for papermaking
US5160789 *28 Dec 19893 Nov 1992The Procter & Gamble Co.Fibers and pulps for papermaking based on chemical combination of poly(acrylate-co-itaconate), polyol and cellulosic fiber
US5213588 *14 Apr 199225 May 1993The Procter & Gamble CompanyAbrasive wiping articles and a process for preparing such articles
US5324392 *14 Mar 199128 Jun 1994Nippon Filcon Co., Ltd.Extendable and heat shrinkable polyamide mono-filament for endless fabric and endless fabric
US5399412 *21 May 199321 Mar 1995Kimberly-Clark CorporationUncreped throughdried towels and wipers having high strength and absorbency
US5429686 *12 Apr 19944 Jul 1995Lindsay Wire, Inc.Apparatus for making soft tissue products
US5443899 *2 Jun 199222 Aug 1995The Procter & Gamble CompanyFibers and pulps for papermaking based on chemical combination of poly(acrylate-co-itaconate), polyol and cellulosic fiber
US5510001 *14 Sep 199423 Apr 1996Kimberly-Clark CorporationMethod for increasing the internal bulk of throughdried tissue
US5542455 *13 Feb 19956 Aug 1996Wangner Systems Corp.Papermaking fabric having diagonal rows of pockets separated by diagonal rows of strips having a co-planar surface
US5580423 *1 Jun 19953 Dec 1996The Procter & Gamble CompanyWet pressed paper web and method of making the same
US5607551 *24 Jun 19934 Mar 1997Kimberly-Clark CorporationSoft tissue
US5616207 *21 Nov 19941 Apr 1997Kimberly-Clark CorporationMethod for making uncreped throughdried towels and wipers
US5637194 *19 Dec 199410 Jun 1997The Procter & Gamble CompanyWet pressed paper web and method of making the same
US5656132 *6 Mar 199512 Aug 1997Kimberly-Clark Worldwide, Inc.Soft tissue
US5667636 *27 Oct 199416 Sep 1997Kimberly-Clark Worldwide, Inc.Method for making smooth uncreped throughdried sheets
US5698074 *1 May 199516 Dec 1997The Procter & Gamble CompanyFibers and pulps for papermaking based on chemical combination of poly (acrylate-co-itaconate), polyol and cellulosic fiber
US5772845 *17 Oct 199630 Jun 1998Kimberly-Clark Worldwide, Inc.Soft tissue
US5776307 *28 Jun 19967 Jul 1998The Procter & Gamble CompanyMethod of making wet pressed tissue paper with felts having selected permeabilities
US5795440 *28 Jun 199618 Aug 1998The Procter & Gamble CompanyMethod of making wet pressed tissue paper
US5806569 *26 Mar 199715 Sep 1998Asten, Inc.Multiplanar single layer forming fabric
US5830316 *16 May 19973 Nov 1998The Procter & Gamble CompanyMethod of wet pressing tissue paper with three felt layers
US5832962 *29 Dec 199510 Nov 1998Kimberly-Clark Worldwide, Inc.System for making absorbent paper products
US5839479 *26 Mar 199724 Nov 1998Asten, Inc.Papermaking fabric for increasing bulk in the paper sheet
US5846379 *1 Mar 19958 Dec 1998The Procter & Gamble CompanyWet pressed paper web and method of making the same
US5853547 *18 Oct 199629 Dec 1998Asten, Inc.Papermaking fabric, process for producing high bulk products and the products produced thereby
US5855739 *22 Apr 19975 Jan 1999The Procter & Gamble Co.Pressed paper web and method of making the same
US5861082 *5 Jun 199519 Jan 1999The Procter & Gamble CompanyWet pressed paper web and method of making the same
US5888347 *2 May 199730 Mar 1999Kimberly-Clark World Wide, Inc.Method for making smooth uncreped throughdried sheets
US5897745 *6 Jun 199727 Apr 1999The Procter & Gamble CompanyMethod of wet pressing tissue paper
US5904811 *21 Apr 199718 May 1999The Procter & Gamble CompanyWet pressed paper web and method of making the same
US5925217 *29 Dec 199520 Jul 1999Kimberly-Clark Tissue CompanySystem for making absorbent paper products
US5932068 *10 Mar 19973 Aug 1999Kimberly-Clark Worldwide, Inc.Soft tissue
US5980691 *12 May 19979 Nov 1999The Procter & Gamble CompanySmooth through air dried tissue and process of making
US6039838 *29 Dec 199521 Mar 2000Kimberly-Clark Worldwide, Inc.System for making absorbent paper products
US6039839 *3 Feb 199821 Mar 2000The Procter & Gamble CompanyMethod for making paper structures having a decorative pattern
US6051105 *3 Aug 199818 Apr 2000The Procter & Gamble CompanyMethod of wet pressing tissue paper with three felt layers
US6103062 *1 Oct 199815 Aug 2000The Procter & Gamble CompanyMethod of wet pressing tissue paper
US6117270 *1 Jul 199912 Sep 2000The Procter & Gamble CompanyPapermaking belts having a patterned framework with synclines therein and paper made therewith
US617144230 Apr 19999 Jan 2001Kimberly-Clark Worldwide, Inc.Soft tissue
US619384712 Jun 200027 Feb 2001The Procter & Gamble CompanyPapermaking belts having a patterned framework with synclines therein
US638721712 Nov 199914 May 2002Fort James CorporationApparatus for maximizing water removal in a press nip
US6434856 *14 Aug 200120 Aug 2002The Procter & Gamble CompanyVariable wet flow resistance drying apparatus, and process of drying a web therewith
US645824817 Mar 20001 Oct 2002Fort James CorporationApparatus for maximizing water removal in a press nip
US651767216 Jul 200111 Feb 2003Fort James CorporationMethod for maximizing water removal in a press nip
US65514537 Dec 199822 Apr 2003The Procter & Gamble CompanySmooth, through air dried tissue and process of making
US666982114 Nov 200130 Dec 2003Fort James CorporationApparatus for maximizing water removal in a press nip
US670163720 Apr 20019 Mar 2004Kimberly-Clark Worldwide, Inc.Systems for tissue dried with metal bands
US673362621 Dec 200111 May 2004Georgia Pacific CorporationApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US6769146 *7 Jan 20033 Aug 2004Milliken & CompanyTransportation seat with release barrier fabrics
US682138610 Feb 200323 Nov 2004The Procter & Gamble CompanySmooth, micropeak-containing through air dried tissue
US682781827 Sep 20027 Dec 2004Kimberly-Clark Worldwide, Inc.Soft tissue
US68333369 Oct 200121 Dec 2004The Procter & Gamble CompanyLaundering aid for preventing dye transfer
US68491577 May 20041 Feb 2005Kimberly-Clark Worldwide, Inc.Soft tissue
US686096824 May 20001 Mar 2005Kimberly-Clark Worldwide, Inc.Tissue impulse drying
US68873495 Sep 20023 May 2005Fort James CorporationApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US688752428 Jan 20023 May 2005The Procter & Gamble CompanyMethod for manufacturing laundry additive article
US71569547 May 20042 Jan 2007Kimberly-Clark Worldwide, Inc.Soft tissue
US7166189 *14 Nov 200523 Jan 2007Kimberly-Clark Worldwide, Inc.Method for making rolls of tissue sheets having improved properties
US718283825 Mar 200427 Feb 2007Georgia Pacific CorporationApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US725616616 Jan 200314 Aug 2007The Procter & Gamble CompanyLaundry articles
US726506719 Jun 19984 Sep 2007The Procter & Gamble CompanyApparatus for making structured paper
US729722611 Feb 200420 Nov 2007Georgia-Pacific Consumer Products LpApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US73005523 Mar 200327 Nov 2007Georgia-Pacific Consumer Products LpMethod for maximizing water removal in a press nip
US732632212 Nov 20045 Feb 2008Georgia Pacific Consumer Products LpApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US736056031 Jan 200622 Apr 2008Astenjohnson, Inc.Single layer papermakers fabric
US740487528 Apr 200429 Jul 2008Georgia-Pacific Consumer Products LpModified creping adhesive composition and method of use thereof
US7476279 *3 Dec 200413 Jan 2009Seikoh Giken Co., Ltd.Cleaning tool for a connecting end face of an optical connecting part and method
US76116055 Dec 20063 Nov 2009Kimberly-Clark Worldwide, Inc.Method for making rolls of tissue sheets having improved properties
US7611607 *27 Oct 20063 Nov 2009Voith Patent GmbhRippled papermaking fabrics for creped and uncreped tissue manufacturing processes
US7678230 *15 Dec 200616 Mar 2010Kimberly-Clark Worldwide, Inc.Environmentally sustainable multiple ply paper product
US77273603 May 20051 Jun 2010Wangner GmbhForming sieve for the wet end section of a paper machine
US77447232 May 200729 Jun 2010The Procter & Gamble CompanyFibrous structure product with high softness
US774935525 Oct 20056 Jul 2010The Procter & Gamble CompanyTissue paper
US775404918 Oct 200713 Jul 2010Georgia-Pacific Consumer Products LpMethod for maximizing water removal in a press nip
US77991768 Oct 200721 Sep 2010Georgia-Pacific Consumer Products LpApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US785794118 Dec 200628 Dec 2010Georgia-Pacific Consumer Products LpApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US792745730 Oct 200919 Apr 2011Kimberly-Clark Worldwide, Inc.Environmentally sustainable multiple ply paper product
US7935409 *14 Nov 20053 May 2011Kimberly-Clark Worldwide, Inc.Tissue sheets having improved properties
US79597619 Apr 200314 Jun 2011Georgia-Pacific Consumer Products LpCreping adhesive modifier and process for producing paper products
US801714514 May 200413 Sep 2011Conopco, Inc.Exfoliating personal care wipe article containing an array of projections
US814261723 Aug 201027 Mar 2012Georgia-Pacific Consumer Products LpApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US816313019 Aug 201024 Apr 2012The Proctor & Gamble CompanyPaper product having unique physical properties
US81780253 Dec 200415 May 2012Georgia-Pacific Consumer Products LpEmbossing system and product made thereby with both perforate bosses in the cross machine direction and a macro pattern
US821127119 Aug 20103 Jul 2012The Procter & Gamble CompanyPaper product having unique physical properties
US823176120 Apr 201131 Jul 2012Georgia-Pacific Consumer Products LpCreping adhesive modifier and process for producing paper products
US82827833 May 20109 Oct 2012The Procter & Gamble CompanyPapermaking belt having a permeable reinforcing structure
US82876933 May 201016 Oct 2012The Procter & Gamble CompanyPapermaking belt having increased de-watering capability
US828769417 Aug 201016 Oct 2012Georgia-Pacific Consumer Products LpApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US829837619 Aug 201030 Oct 2012The Procter & Gamble CompanyPatterned framework for a papermaking belt
US831361719 Aug 201020 Nov 2012The Procter & Gamble CompanyPatterned framework for a papermaking belt
US836127816 Sep 200929 Jan 2013Dixie Consumer Products LlcFood wrap base sheet with regenerated cellulose microfiber
US844482520 Apr 201021 May 2013Wangner GmbhForming sieve for the wet end section of a paper machine
US847590514 Feb 20082 Jul 2013High Voltage Graphics, IncSublimation dye printed textile
US851252427 Mar 201220 Aug 2013The Procter & Gamble CompanyPatterned framework for a papermaking belt
US853548113 Jun 201217 Sep 2013Georgia-Pacific Consumer Products LpApparatus and method for degrading a web in the machine direction while preserving cross-machine direction strength
US864710516 Apr 201211 Feb 2014Georgia-Pacific Consumer Products LpEmbossing system and product made thereby with both perforate bosses in the cross machine direction and a macro pattern
US865799714 Dec 201225 Feb 2014The Procter & Gamble CompanyPaper product having unique physical properties
US20090239025 *4 Mar 200924 Sep 2009High Voltage Graphics, Inc.Flocked articles having a woven graphic design insert and methods of making the same
USRE42968 *15 Mar 201129 Nov 2011The Procter & Gamble CompanyFibrous structure product with high softness
DE3008344A1 *5 Mar 198018 Sep 1980Procter & GamblePapiermaschinen-tuch
DE3127359A1 *10 Jul 198115 Jul 1982Albany Int CorpTextilmaterial fuer einen trockenfilz und daraus hergestellter trockenfilz
EP1212483A1 6 Sep 200012 Jun 2002THE PROCTER & GAMBLE COMPANYPapermaking apparatus and process for removing water from a cellulosic web
EP1632604A11 Sep 20058 Mar 2006Fort James CorporationMulti-ply paper product and method of making the same
WO1996004418A1 *31 Jul 199515 Feb 1996Wangner Systems CorpWoven fabric
WO1997024487A1 *20 Dec 199610 Jul 1997Kimberly Clark Tissue CompanyImproved system for making absorbent paper products
WO1997024488A1 *20 Dec 199610 Jul 1997Kimberly Clark Tissue CompanyImproved system for making absorbent paper products
WO2011139950A22 May 201110 Nov 2011The Procter & Gamble CompanyA papermaking belt having a permeable reinforcing structure
WO2011139999A13 May 201110 Nov 2011The Procter & Gamble CompanyA papermaking belt having increased de-watering capability
WO2012024077A12 Aug 201123 Feb 2012The Procter & Gamble CompanyA papermaking belt with a knuckle area forming a geometric pattern that is repeated at ever smaller scales to produce irregular shapes and surfaces
WO2012024459A118 Aug 201123 Feb 2012The Procter & Gamble CompanyA papermaking belt with a knuckle area forming a geometric pattern that is repeated at ever smaller scales to produce irregular shapes and surfaces
WO2012024460A118 Aug 201123 Feb 2012The Procter & Gamble CompanyA paper product having unique physical properties
WO2012024463A218 Aug 201123 Feb 2012The Procter & Gamble CompanyA paper product having unique physical properties
Classifications
U.S. Classification162/113, 162/116, 139/425.00A, 162/117, 156/183
International ClassificationD21F11/00, D21F11/14, D21H27/00
Cooperative ClassificationD21F11/006, D21F11/14
European ClassificationD21F11/14, D21F11/00E