BACKGROUND OF THE INVENTION Cellulosic fibrous structures are a staple of everyday life. Cellulosic fibrous structures are used as consumer products for paper towels, toilet tissue, facial tissue, napkins and the like. The large demand for such paper products has created a demand for improved versions of the products and the methods of their manufacture.

Multiple ply cellulosic fibrous structures are very well known in the art of consumer products. Such products are cellulosic fibrous structures having more than one, typically two, plies superimposed in face-to-face relationship to form a laminate.

It is known in the art to emboss sheets comprising multiple plies of tissue for aesthetic purposes and to maintain the plies in face-to-face relation during use. In addition, embossing can increase the surface area of the plies thereby enhancing their bulk and water holding capacity.

During the embossing process, the plies are fed through a nip formed between juxtaposed axially parallel rolls. Embossment knobs on these rolls compress like regions of each ply into engagement and contacting relationship with the opposing ply. The compressed regions of the plies produce an aesthetic pattern and provide a means for joining and maintaining the plies in face-to-face contacting relationship.

Embossing is typically performed by one of two processes, knob-to-knob embossing or nested embossing. Knob-to-knob embossing consists of axially parallel rolls juxtaposed to form a nip between the knobs on opposing rolls. Nested embossing consists of embossment knobs of one roll meshed between the embossment knobs of the other roll. Examples of knob-to-knob embossing and nested embossing are illustrated in the prior art by U. S. Patents 3,414,459 issued December 3,1968 to Wells and commonly assigned; 3,547,723 issued December 15, 1970 to Gresham; 3,556,907 issued January 19,1971 to Nystrand; 3,708,366 issued January 2,1973 to Donnelly; 3,738,905 issued June 12,1973 to Thomas; 3,867,225 issued February 18,1975 to Nystrand and 4,483,728 issued November 20,1984 to Bauernfeind.

Knob to knob embossing produces a cellulosic fibrous structure composed of pillowed regions which enhance the thickness of the product. However, the pillows have a tendency to collapse under pressure due to lack of support. Consequently, the thickness benefit is typically lost during the balance of the converting operation and subsequent packaging, diminishing the quilted appearance sought by embossing.

Nested embossing has proven to be the preferred process for producing products exhibiting a softer more quilted appearance that is maintained throughout the balance of the converting process including packaging. With nested embossing, one ply has a male pattern, while the other ply has a female pattern. As the two plies travel through the nip of the embossment rolls, the patterns are meshed together.

Nested embossing aligns the knob crests on the male embossment roll with the low areas on the female embossment roll. As a result, the embossed sites produced on one ply provide support for the embossed sites on the other ply.

The lamination point at the nip between nested embossment rolls is typically eliminated, since the knobs on the nested embossment rolls do not touch. This necessitates the addition of a marrying roll to apply pressure for lamination. Typical marrying rolls are solid resulting in the lamination of every potential laminating point as shown in U. S. Patent No. 3,867,225 issued February 18,1975 to Nystrand.

The nested embossment rolls may be designed such that the knobs on one roll contact the periphery of the other embossing roll providing a lamination point, thereby eliminating the need for a marrying roll. Such nested embossing arrangement is shown in U. S. Patent No. 5,468,323 issued November 21,1995 to McNeil. This arrangement also provides a means for improving the bond strength between the plies by enabling a glue applicator roll to be used in conjunction with each of the embossment rolls providing an adhesive joint at each of the embossed sites.

Consumer testing of products having embossed cellulosic fibrous structures have determined that a softer, more quilted appearance is desired. Consumers desire products having relatively high caliper with aesthetically pleasing decorative patterns exhibiting a high quality cloth-like appearance. Such attributes must be provided without sacrificing the products'other desired qualities of softness, absorbency, drape (limpness) and bond strength between the plies.

Different attempts have been made in the art to produce paper products exhibiting superior functional properties as well as aesthetically pleasing decorative qualities. The present invention provides an embossed multiple ply tissue where the embossment pattern includes a plurality of indicia comprising aesthetically pleasing decorative images. The bonds between the plies are limited to the embossed indicia.

For the present invention, the multiple plies are selectively bonded at all or less than all of the indicia by adhesive or high pressure embossing. High pressure embossing selective indicia prevents separation of the multiply product during use and induces a glassine appearance that improves the decorative nature of the product.

SUMMARY OF THE INVENTION The present invention comprises an embossed multiple ply tissue product wherein the embossment pattern includes a plurality of indicia. The indicia comprise one or more decorative images that are aesthetically pleasing. The multiple plies of tissue are selectively bonded in a face to face relationship to prevent separation during use and provide a soft product having improved drape. In one embodiment the plies are selectively bonded by high pressure embossing selective indicia providing a glassine look which enhances the decorative nature of the product. In another embodiment, the plurality of indicia are disposed within a latticework of cells composed of rows of embossed elements.

The invention further comprises a process for producing such multiple ply cellulosic structures. The process comprises the steps of providing a first ply embosser and a second ply embosser, wherein each said first and second ply embossers comprises a pressure roll juxtaposed axially parallel to a pattern roll to form a nip therebetween. Each of the pattern rolls comprises a plurality of radially oriented embossment knobs projecting from a periphery. The embossment knobs on at least one of the pattern rolls form a plurality of indicia comprising decorative images. First and second plies of tissue are interposed between the nips of the first and second ply embossers such that the embossment patterns are compressed thereon. Subsequently, the first and second plies are joined in a face to face relationship and selectively bonded.

In one embodiment, the process includes a means for selectively bonding the two plies by providing a steel anvil roll juxtaposed axially parallel to one of the two pattern rolls for selectively bonding the plies via high pressure embossing.

BRIEF DESCRIPTION OF THE DRAWINGS These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where: Figure 1 is a schematic side elevational view of an apparatus used to perform nested embossing and adhesive bonding of two plies according to the present invention.

Figure 2 is a side view of a nip formed between the two pattern rolls displayed in Figure 1.

Figure 3 is a side elevational view of an apparatus used to perform nested embossing and bonding of two plies utilizing high pressure embossing according to the present invention.

Figure 4 is a side view of a high pressure embossing nip formed between a pattern roll and the steel anvil roll displayed in Figure 3.

Figure 5 is a fragmentary vertical sectional view of an embossed multiple ply paper product according to the present invention.

Figure 6a is a plan view of linear flower shaped indicia and heart shaped indicia.

Figure 6b is a plan view of the indicia shown in Figure 8a comprising crenulated patterns.

Figure 7a is a plan view of a first ply showing flower shaped indicia arranged in a diagonal pattern.

Figure 7b a plan view of a first ply showing flower shaped and heart shaped indicia arranged in a diagonal pattern.

Figure 8a is a fragmentary plan view of the multiple ply paper product displaying a latticework embossment pattern on the first ply.

Figure 8b is a fragmentary plan view of the multiple ply paper product displaying a latticework embossment pattern on the second ply.

Figure 8c is a fragmentary plan view of the multiple ply paper product displaying the first ply embossment pattern illustrated in Figure 8a nested within the second ply embossment pattern illustrated in Figure 8b.

Figure 9 is a fragmentary plan view of a latticework embossment pattern showing apices and vertices skewed relative to CD and MD Figure 10 is a plan view of the first ply showing the embossed latticework of cells having flower shaped indicia disposed therein.

DETAILED DESCRIPTION OF THE INVENTION Definitions As used herein, the following terms have the following meanings: "Machine direction", designated MD, is the direction parallel to the flow of paper through the papermaking equipment.

"Cross machine direction", designated CD, is the direction perpendicular to the machine direction in the X-Y plane.

"Embossing"refers to the process of deflecting a relatively small portion of a cellulosic fibrous structure normal to its plane and impacting the projected portion of the fibrous structure against a relatively hard surface to permanently disrupt the fiber to fiber bonds.

A"nip"is a loading plane connecting the centers of two parallel axes.

"Nonrandom,"refers to a predictable disposition and may occur as a result of known and predetermined features of the manufacturing process.

"Repeating"means the pattern is formed more than once.

"Discrete,"means the adjacent embossed sites are not contiguous.

"Essentially continuous"refers to a region extending substantially throughout the fibrous structure in one or both of its principal directions.

"Crenulated emboss elements"are emboss elements formed into crenels and merlons such that the side of the emboss element would resemble the top of a castle wall having spaced projections which are merlons and depressions therebetween which are crenels.

An"indicia"is a distinctive marking, exhibiting a decorative aspect.

A"latticework"is a pattern of small intersecting diagonal or zigzag segments or angles.

A"cell"is a unit of a two-dimensional array comprising a group of individual enclosures.

The specification contains a detailed description of (1) the embossing laminating system of the present invention and (2) the finished paper product of the present invention.

(1) The Embossing/Laminating Equipment Illustrated in Figure 1 is an embossing and laminating system used to manufacture cellulosic fibrous structures for consumer paper products. The system depicted performs a process referred to in the prior art as nested embossing. In nested embossing two plies 20 and 22 are embossed between mated pressure rolls 30 and 32 and likewise mated pattern rolls 34 and 36. The pressure rolls 30 and 32 and pattern rolls 34 and 36 are juxtaposed with parallel axes to form three nips, a first nip between the first pressure roll 30 and the first pattern roll 34, a second nip between the second pressure roll 32 and the second pattern roll 36, and a third nip between the first and second pattern rolls 34 and 36. Although the present invention is equally applicable to all types of consumer paper products such as paper towels, toilet tissue, facial tissue, napkins, and the like, the embossing process used to produce the multiple ply tissue 24 as well as the multiple ply tissue 24 produced thereby are representative of toilet tissue.

Pattern rolls 34 and 36 have knobs 33 which extend radially outwardly and contact the periphery of the respective pressure rolls 30 or 32 at the respective nips.

Each ply 20 or 22 to be joined into the resulting multiple ply cellulosic fibrous structure 24 is fed through one of the nips between the pattern rolls 34 or 36 and the respective pressure roll 30 or 32. Each ply 20 or 22 is embossed in the nip by the knobs 33 of the respective pattern roll 34 or 36.

For the present invention, the embossment pattern disposed on one or both of the pattern rolls 34,36 includes a plurality of indicia comprising decorative images such as flowers and heart shapes. In an alternate embodiment the embossment pattern includes a latticework of cells having indicia disposed therein on one or both of the pattern rolls 34,36. In still another embodiment, the embossment pattern on the first pattern roll includes a latticework of cells comprising n rows of embossment elements forming cells with indicia disposed therein, while the second pattern roll 36 includes a latticework of cells comprising n+l arcuate rows of embossment elements.

After embossing, one of the plies 20 or 22 may have adhesive applied to the resulting crests 27 of the embossed sites 26 by an adhesive applicator roll 37. The adhesive applicator roll 37 may be utilized in conjunction with either ply 20 or 22. In this process, adhesive is applied to only the crests 27 of the embossed sites 26 of ply 20 or 22 since the crests 27 of the embossed sites 26 are the only portions of the ply 20 or 22 contacting the adhesive applicator roll 37. For the present invention, the adhesive applicator roll 37 is synchronized with one of the two pattern rolls 34,36 to apply adhesive to the selective embossed sites comprising indicia in order to limit the bonds between the two plies to the indicia.

The plies 20 and 22 are then fed through the nip between the first and second pattern rolls 34 and 36. The patterns on each of the two rolls 34,36 are arranged such that each embossed indicia on one or both rolls mesh with a nonembossed region on the opposing ply at the nip formed between the two rolls 34,36. For pattern rolls comprising n and n+1 rows of embossment elements disposed thereon, the n rows of embossment elements on the first pattern roll 34 mesh within the n+1 rows of embossment elements on the second pattern roll 36 at the nip.

As shown in Figure 2, the knobs 33 on each respective pattern roll 34,36 approach the periphery 31 of the neighboring pattern roll without making contact therewith. In this nip, the plies 20 and 22 are juxtaposed in a face-to-face relationship with the crests 27 of the embossed sites 26 on one ply 20,22 registered with nonembossed regions 25 on the other ply 20,22.

The two plies 20 and 22 are then fed through a nip between the pattern roll 34 associated with the adhesive applicator roll 37 and a marrying roll 38, to insure the crests of the first ply 20 embossed sites 26 having the adhesive applied from the adhesive applicator roll 37 are bonded to the nonembossed regions 25 of the second ply 22. Contact between the pattern roll 34 and the marrying roll 38 is limited to the embossed sites 26 of the first ply 20.

In an alternate embodiment (not shown), the pattern rolls 34,36 can be designed such that the knobs 33 on each of the rolls contact the periphery of the opposing roll bonding the plies 20,22 at the nip which is formed therebetween, thus eliminating the need for the marrying roll 38. Such arrangement is disclosed in commonly assigned U. S. Patent No 5,468,323 issued November 21,1995 to McNeil and is incorporated herein by reference. For such an arrangement, an adhesive applicator roll 37 may be used in conjunction with each of the pattern rolls so that lamination points may be formed between the plies at each of the knobs 33 on the two pattern rolls 34,36.

In another embodiment, the two plies 20,22 are bonded by high pressure embossing. As shown in Figure 3, the adhesive applicator roll 37 is eliminated and the first pattern roll 34 is paired with a steel anvil roll 50 in place of the marrying roll 38. Once the two plies pass through the nip between the first and second pattern rolls 34,36 and are thereby juxtaposed in a face to face relationship, the plies 20,22 are made to pass through the nip between the first pattern roll 34 and the steel anvil roll 50. As shown in Figure 4, the knobs 33 on the first pattern roll 34 act in conjunction with land areas 52 on the steel anvil roll 50 to apply high unit pressures to the surfaces of the two plies 20,22 disposed therebetween. The land areas 52 on the steel anvil roll have sizes which correspond to and slightly exceed the dimension associated with the interfacing knob portions of the mating pattern roll 34 where the bonds are to occur.

For the present invention, multiply products joined by high pressure embossing are selectively bonded at the indicia. For tissues having more than one type indicia, the selective bonds may be limited to one indicia type such that the glassine look further distinguishes the bonded indicia from the nonbonded indicia, thus further enhancing the decorative quality of the tissue.

High pressure embossing bonds the two plies by interlocking the fibers and reducing them to plastic. The resulting bonds exhibit a glassine appearance which is aesthetically pleasing. Bonding via high pressure embossing is disclosed in U. S.

Patent 3,323,983 issued September 8,1964 to Palmer and is incorporated herein by reference.

(2) The Embossed Paper Product The present invention provides a tissue paper product having functional characteristics of softness, absorbency, and drape as well as exhibiting aesthetically pleasing decorative attributes. Such aesthetically pleasing features include patterns of indicia displaying a high quality cloth-like appearance and particularly, a softer, more quilted look.

For the present invention, the embossment patterns on the multiply tissue include indicia comprising decorative images. The plies are joined in a face-to-face arrangement with the bond locations being limited to the indicia. Bonding the plies at the indicia produces a more permanent decorative figure that inhibits dissipation caused by compressive forces, humidity, and absorption. In addition, by limiting the bond sites to the indicia a softer tissue with improved drape is produced.

Referring to Figure 5, the cellulosic fibrous structure 20 according to the present invention comprises two plies 20 and 22 joined in face-to-face relation. Each of the plies 20 and 22 has two distinct zones, an essentially continuous nonembossed region 24, and discrete embossed sites 26 projecting generally outward therefrom and preferably orthogonal thereto. It is to be understood that each ply 20 or 22 may be directly joined to the opposite ply 22 or 20, or, may be connected through an intermediate layer (not shown) interposed between the plies 20 and 22.

For the present invention, the embossment pattern comprises a plurality of one or more types of indicia distributed throughout one or both plies in a nonrandom manner. Although the indicia may comprise any decorative image, for the present invention, the indicia include flowers 92 and heart shapes 94.

The indicia 90 may comprise a linear pattern as shown in Figure 6a, or a crenulated pattern as shown in Figure 6b. The linear pattern comprises an essentially continuous embossed design while the crenulated pattern comprises crenulated emboss elements. The crenulated emboss elements add bulk to the paper substrate and enhance the definition and retention of the embossed pattern. Crenulated decorative images are disclosed in U. S. Patent 5,620,776 issued April 15,1997 to Schulz.

In one embodiment shown in Figure 7a, the first ply 20 comprises indicia 90 disposed in a nonrandom pattern running diagonal to both MD and CD. The pattern alternates between a diagonal nonembossed row to a diagonal row comprising nonembossed regions and regions having embossed flower shaped indicia disposed therein.

In an alternate embodiment shown in Figure 7b, the embossed pattern comprises two indicia 90 comprising a flower 92 and a heart 94 disposed in a nonrandom pattern running diagonal to both MD and CD. For this embodiment, every other diagonal row in the pattern shifts from having all heart shaped indicia to alternating heart and flower shaped indicia.

The distal end of each embossed site 26 on each of the two plies 20,22 projects towards and contacts the nonembossed region 25 of the opposite ply.

Bonding the plies at the embossed sites 26 improves the appearance of the tissue by providing a more permanent structure that inhibits subsequent dissipation caused by compressive forces, humidity, and absorption. The two plies 20,22 may be bonded at every embossed site 26 or at selective discrete sites depending on the process.

The number of bond sites occurring between the two plies not only affects the bond strength but also the product stiffness and drape. Whether the plies 20,22 are joined adhesively or via high pressure embossing, the greater the bond area the stiffer the tissue. Stiffness has a direct impact on product softness and drape. Therefore, it is preferred to minimize the bond area by limiting the region bonded between the two plies 20,22 to selective discrete sites.

The two plies 20,22 may be joined at selective sites by adhesive bonds or high pressure embossments using the processes previously described. For selective adhesive bonds, the adhesive applicator roll is synchronized with selective discrete embossment locations on the mating pattern roll. Alternatively, for selective high pressure bonds, land areas are formed on the steel anvil roll matching the selective discrete embossment locations on the neighboring pattern roll. The sizes of the land areas correspond to and slightly exceed the dimensions of the embossments on the pattern roll where the selective bonds are desired.

As previously described, high pressure embossing produces a glassine bond site that enhances the decorative quality of the tissue. Therefore, for the present invention, it is preferred to form the selective bond sites via high pressure embossing.

Particularly, it is preferred to bond the two plies by high pressure embossing such that the area bonded between the two plies 20,22 comprises about 2% to about 5% of the interfacing surface area between the two plies 20,22.

Although any pattern of embossment elements 26 may be selected for the selective bond sites, it is preferred to choose a nonrandom pattern of embossment elements providing adequate bond strength using minimal surface area. For the present invention, the first ply 20 represents the outside ply of a multiple ply tissue which is typically exposed to a consumer during use. In order to further enhance the decorative quality of the product, it is preferred to limit the selective bond sites to the indicia 90 embossed on the first ply 20. For embodiments comprising more than one type of indicia, such as a flower 92 and a heart shape 94, it is preferred to limit the selective bond sites to one type of indicia 90 embossed on the first ply 20.

The embossment pattern for the present invention may include a latticework of cells. Figure 8a depicts a plan view of the latticework of cells embossed on the first ply 20 and Figure 8b depicts a plan view of the latticework of cells embossed on the second ply 22. Although the latticework of cells on each of the two plies are composed of arcuate rows of discrete embossment elements 26 forming apices 62 and vertices 64, the latticework of cells may comprise other configurations having rectilinear or serpentine rows of embossment elements.

As shown in figures 8a and 8b, the latticework of cells on the first ply 20 are defined by single arcuate rows 66 of embossment elements 26 while the cells on the second ply 22 are defined by two rows 67 of embossment elements 26. Once the two plies 20,22 are joined together in a face to face relationship, the single arcuate rows 66 on the first ply become nested within the two rows 67 on the second ply. This nested arrangement, illustrated in Figure 8c, provides a softer, more quilted look.

Although the latticework of cells for the two plies 20,22 depicted in Figures 8a, 8b, and 8c comprises a first ply 20, single row 66 latticework of cells nested within a second ply 22, double row 67 latticework of cells, it is apparent that other nested latticework arrangements would provide similar or improved cloth like appearances. For the present invention, it is preferred to nest every row 66 of embossment elements 26 on the first ply 20 between two rows 67 of embossment elements 26 on the second ply. In other words, if the latticework of cells on the first ply 20 comprises n rows of embossment elements 26 then it is preferred that the latticework of cells on the second ply 22 comprises n+l rows of embossment elements 26 (where n is an integer 1,2,3... etc.).

For the nested arrangement illustrated in Figure 8c, each of the embossment elements 26 forming the n rows 66 on the first ply can be radially aligned or nonaligned with the embossment elements 26 forming the n+1 rows 67 on the second ply. In addition, for the nested arrangement, each of the rows 66 of embossment elements 26 on the first ply can be arranged equidistant or nonequidistant from the adjacent rows 67 of embossment elements on the second ply 22.

As shown in Figures 8a and 8b, the rows 66 making up the latticework of cells are disposed in a repeating array extending transversely in the CD. The latticework is typically arranged such that the apices 62 and the vertices 64 are aligned parallel to both the MD and the CD. In an alternate embodiment, the latticework of cells are offset in the CD. As illustrated in Figure 9, the cells are arranged such that the vertices and apices are skewed at an angle 80 which is offset from the CD. Such skewed angle may range from about 4° to about 10°.

As previously explained, for the present invention, the first ply 20 represents the outside ply of a multiple ply tissue which is typically exposed to a consumer during use. In order to further enhance the decorative quality of the product, indicia 90, illustrated in Figure 8a, may be disposed within the latticework of cells 68 on the first ply 20 in a nonrandom, repeating manner. The space within the latticework of cells on the first ply 20 for such indicia 90 is made available by limiting the number of rows of embossment elements 26. Figure 10 shows flower shaped indicia disposed within the latticework of cells in a nonrandom diagonal pattern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is intended to cover in the appended claims all such changes and modifications that are within the scope of the invention.