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Publication numberUS20050241789 A1
Publication typeApplication
Application numberUS 10/835,883
Publication dateNov 3, 2005
Filing dateApr 30, 2004
Priority dateApr 30, 2004
Publication number10835883, 835883, US 2005/0241789 A1, US 2005/241789 A1, US 20050241789 A1, US 20050241789A1, US 2005241789 A1, US 2005241789A1, US-A1-20050241789, US-A1-2005241789, US2005/0241789A1, US2005/241789A1, US20050241789 A1, US20050241789A1, US2005241789 A1, US2005241789A1
InventorsKiran Reddy
Original AssigneeKimberly-Clark Worldwide, Inc.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Surface treated paper product
US 20050241789 A1
Abstract
A soft tissue product includes a surface treatment composition disposed on a treated portion that extends to the edges of the product, but which leaves the corners of the product untreated. The shape of the treated portion effectively ensures consumer benefit while reducing the total amount of additive composition on the product by placing the treatment composition in the portion of the product that is most likely to come into contact with the skin of a user.
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Claims(23)
1. A tissue product comprising a substrate defining a major surface having a rectangular planar surface area defining first and third opposed edges, second and fourth opposed edges, and first, second, third, and fourth corner portions, the tissue product further comprising a treated portion comprising an additive composition disposed on the major surface, wherein the treated portion intersects the first, second, third, and fourth edges of the major surface, and even further wherein the corner portions of the major surface are untreated.
2. The tissue product of claim 1, wherein the treated portion has a substantially parallelogram shape, the treated portion being positioned on the major surface wherein the corners of the parallelogram-shaped treated portion substantially bisect the edges of the major surface.
3. The tissue product of claim 1, wherein the treated portion has a substantially elliptical shape, the circumference of the elliptical-shaped treated portion substantially bisecting the edges of the major surface.
4. The tissue product of claim 1, wherein the additive composition is applied at an add-on level of from about 0.01 to about 20 percent of the basis weight of the substrate.
5. The tissue product of claim 1, wherein the treated portion comprises from about 100 to about 1,000,000 individual deposits of treatment composition per square inch of the planar surface area.
6. The tissue product of claim 1, wherein the treated portion covers from about 50 to about 80 percent of the planar surface area.
7. The tissue product of claim 1, wherein the treated portion is divided into two parts separated by an intervening untreated portion.
8. The tissue product of claim 7, wherein the intervening untreated portion extends from the first edge of the major surface to the third edge.
9. The tissue product of claim 8, wherein the two parts of the treated portion each extends from the first edge of the major surface to the third edge.
10. The tissue product of claim 8, wherein the tissue product is folded along the intervening untreated portion.
11. The tissue product of claim 1, wherein the additive composition comprises from about 30 to about 90 weight percent oil and from about 10 to about 40 weight percent wax, said composition having a melting point of from about 30° C. to about 70° C.
12. The tissue product of claim 11, wherein the add-on level of the additive composition is from about 3 to about 15 weight percent of the basis weight of the substrate.
13. The tissue product of claim 11, wherein the additive composition further comprises from about 5 to about 40 weight percent fatty alcohol.
14. The tissue product of claim 11, wherein the amount of oil in the composition is from about 40 to about 70 weight percent.
15. The tissue product of claim 11, wherein the amount of wax in the composition is from about 10 to about 30 weight percent.
16. The tissue product of claim 1, wherein the additive composition comprises a silicone compound.
17. The tissue product of claim 16, wherein the add-on level is from about 0.5 to about 3 weight percent of the basis weight of the substrate.
18. A hand towel comprising the tissue product of claim 1.
19. A facial tissue comprising the tissue product of claim 1.
20. A multi-ply tissue product comprising first and second outer plies and an inner ply, wherein the outer plies comprise the tissue product of claim 1.
21. A method of making a tissue product comprising the steps of: providing a tissue web and an additive composition; applying the additive composition to the tissue web; and recovering the tissue product of claim 1.
22. A tissue product comprising a substrate defining a major surface having a rectangular planar surface area defining first and third opposed edges, second and fourth opposed edges, and first, second, third, and fourth corner portions, the tissue product further comprising a treated portion comprising an additive composition disposed on the major surface, wherein the treated portion extends from the first edge of the major surface to the third edge, further wherein the treated portion extends from the second edge of the major surface to the fourth edge, and even further wherein the corner portions of the major surface are untreated.
23. A tissue product comprising a substrate defining a major surface having a rectangular planar surface area, the tissue product further comprising a treated portion comprising an additive composition disposed on the major surface, the treated portion having a substantially parallelogram shape, the treated portion being positioned on the major surface wherein the corners of the parallelogram-shaped treated portion substantially bisect the sides of the major surface.
Description
BACKGROUND OF THE INVENTION

Absorbent tissue products such as facial tissue, bath tissue, hand towels, and so forth have been used to absorb fluids on the skin and leave the skin dry. Frequent use of these products may, however, tend to irritate or abrade the skin. In particular, during frequent hand-drying, the skin can become so irritated as to appear red and be sore to the touch. To reduce skin irritation, tissue products have included additives applied to the tissue surfaces to reduce or eliminate irritated skin during heavy use periods. The additives can enhance sheet softness perceptions by reducing the stiffness of the sheet, making it more drapeable, or by providing lubricity, helping the sheet glide across the surface of the skin. The additives may also be deposited on the skin.

The general approach in the industry has been that the greater the quantity of additive on the tissue, the greater the benefit. Contributing to this approach is the fact that particular additives may be absorbed into the tissue, leaving less additive on the surface to provide the intended benefit. One major drawback to the “more is better” philosophy is cost. Additives to address skin irritation can represent a significant portion of the cost of a tissue sheet. Additionally, application of the additives to the entire surface of a tissue sheet can result in waste when the user does not utilize the entire sheet.

Thus, there is a need for an additive-treated tissue product adapted to maximize the effectiveness and efficiency of the additive and to enhance sheet softness and/or reduce skin irritation and redness.

SUMMARY OF THE INVENTION

In one aspect of the invention, a tissue product includes a substrate defining a major surface having a rectangular planar surface area defining first and third opposed edges, second and fourth opposed edges, and first, second, third, and fourth corner portions. The tissue product further includes a treated portion including an additive composition disposed on the major surface wherein the treated portion intersects the first, second, third, and fourth edges of the major surface, and even further wherein the corner portions of the major surface are untreated. In one embodiment, the treated portion has a substantially parallelogram shape and is positioned on the major surface wherein the corners of the parallelogram-shaped treated portion substantially bisect the edges of the major surface. In another embodiment, the treated portion has a substantially elliptical shape and the circumference of the elliptical-shaped treated portion substantially bisects the edges of the major surface.

In one embodiment, the treated portion may be divided into more than one part, for example, two, three, or four parts, with the parts being separated by one or more intervening untreated portions. When the tissue product includes two treated parts on one surface, the intervening untreated portion desirably extends from one edge of the major surface to the opposed or opposite edge. Additionally, when the tissue product includes two treated parts on one surface, the two parts of the treated portion desirably each extend from one edge of the major surface to the opposed or opposite edge. The tissue product may be folded, and when the tissue product includes two treated parts on one surface the tissue product is, when folded, desirably folded along the intervening untreated portion.

The additive composition desirably may be applied at an add-on level of from about 0.01 to about 20 percent of the basis weight of the substrate. Desirably, the treated portion covers from about 50 to about 80 percent of the planar surface area of the tissue product. In one embodiment, the treated portion includes from about 100 to about 1,000,000 individual deposits of treatment composition per square inch of the planar surface area.

In one embodiment, the additive composition includes from about 30 to about 90 weight percent oil and from about 10 to about 40 weight percent wax, said composition having a melting point of from about 30° C. to about 70° C. Desirably, the amount of oil in the composition is from about 40 to about 70 weight percent and the amount of wax in the composition is from about 10 to about 30 weight percent. The add-on level of this additive composition is desirably from about 3 to about 15 weight percent of the basis weight of the substrate. The additive composition may further include from about 5 to about 40 weight percent fatty alcohol.

In another embodiment, the additive composition includes a silicone compound. The add-on level is desirably from about 0.5 to about 3 weight percent of the basis weight of the substrate.

The tissue product of the invention may be suitable for use, for example, as facial tissue, bath tissue, hand towels, napkins, multi-ply tissue products, and so forth.

In one aspect of the invention, a method of making a tissue product includes the steps of: providing a tissue web and an additive composition; applying the additive composition to the tissue web; and recovering the tissue product of claim 1. In one embodiment, the additive composition is applied to the tissue web using a rotogravure process.

In another aspect of the invention, a tissue product includes a substrate defining a major surface having a rectangular planar surface area defining first and third opposed edges, second and fourth opposed edges, and first, second, third, and fourth corner portions. The tissue product further includes a treated portion that includes an additive composition disposed on the major surface, wherein the treated portion extends from the first edge of the major surface to the third edge, and further wherein the treated portion extends from the second edge of the major surface to the fourth edge, and even further wherein the corner portions of the major surface are untreated.

In a further aspect of the invention, a tissue product includes a substrate defining a major surface having a rectangular planar surface area. The tissue product further includes a treated portion that includes an additive composition disposed on the major surface. The treated portion has a substantially parallelogram shape and is positioned on the major surface wherein the corners of the parallelogram-shaped treated portion substantially bisect the sides of the major surface.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of this invention, including the best mode shown to one of ordinary skill in the art, is set forth in this specification.

FIG. 1 representatively shows a tissue product according to the present invention.

FIG. 2 representatively shows an alternate embodiment of a tissue product according to the present invention.

FIG. 3 is a schematic process flow diagram for a method of making a tissue base sheet in which an additive composition is applied to a creped tissue sheet during manufacture using a heated rotogravure printer.

DETAILED DESCRIPTION OF THE INVENTION

Reference now will be made to the embodiments of the invention, one or more examples of which are set forth below. Each embodiment is provided by way of explanation of the invention, not as a limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in this invention without departing from the scope or spirit of the invention. For example, features illustrated or described as part of one embodiment can be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present invention are disclosed in or are obvious from the following detailed description

It has now been discovered that, surprisingly, tissue products containing an additive adapted to reduce skin irritation and redness can be manufactured with substantially lower total add-on amounts while maintaining the overall effectiveness of the additive. Applicants have discovered that application of additive to the surface of a tissue product to form a treated portion that receives more contact with the skin of a user during the use of the tissue product can be used effectively to provide consumer benefit while minimizing the total amount of additive on the tissue. It is theorized that consumers do not use the entire surface area of tissue products. For example, in studies conducted on hand drying, it has been shown that the corners of rectangular towels are used to a much lesser extent than the central portion of the hand towels. Therefore, concentrating the additive in the portion of the paper product that is more extensively utilized will maximize the benefit to the user for a given amount of additive applied to the tissue product. Alternatively, similar performance is achieved at a lower cost.

FIG. 1 representatively shows a tissue product 100 that includes a substrate 102 that defines a major surface 104. Desirably, the major surface 104 has a substantially rectangular planar surface area. The major surface 104 defines a plurality of edges 106, 108, 110, 112. The first edge 106 is opposed by the third edge 110. The second edge 108 is opposed by the fourth edge 112. The tissue product further includes a treated portion 114 that includes an additive composition disposed on the major surface 104. The treated portion 114 approaches and/or intersects the edges 106, 108, 110, 112. The tissue product 100 further includes corner portions 116, 118, 120, 122 that remain untreated by the additive composition. The additive composition is disposed on the treated portion 114 at an add-on level that may range from about 0.01 percent to about 40 percent of the basis weight of the substrate. The treated portion 114 may have any of a variety of contiguous shapes. For example, the treated portion 114 may be shaped generally as a diamond or parallelogram as depicted in FIG. 1. Alternatively, the treated portion 114 may be shaped generally as a circle, ellipse, oval, and so forth. In a further embodiment, the treated portion 114 may have an irregular shape that extends to the edges of the of the tissue product 100 and allows the corner portions 116, 118, 120, 122 to remain untreated.

Alternate embodiments include tissue products having a treated portion that is separated into two or more parts. FIG. 2 representatively shows a tissue product 200 that includes a substrate 202 that defines a major surface 204. Desirably, the major surface 204 has a substantially rectangular planar surface area. The major surface 204 defines a plurality of edges 206, 208, 210, 212. The first edge 206 is opposed by the third edge 210. The second edge 208 is opposed by the fourth edge 212. The tissue product further includes a treated portion 214 that includes an additive composition disposed on the major surface 204. The treated portion 214 includes two sections 214A, 214B. The first section 214A approaches and/or intersects the first, second, and third edges 206, 208, 210. The second section 214B approaches and/or intersects the second, third, and fourth edges 208, 210, 212. The tissue product 200 further includes corner portions 216, 218, 220, 222 that remain untreated by the additive composition. Optionally, the tissue product 200 may further include a fold 224. Desirably, the fold 224 is placed between the first section 214A and the second section 214B. It is also contemplated that the tissue product may include multiple folds, some of which may extend through the treated portion of the tissue product, depending upon the desired configuration or intended use.

The tissue product of this invention can be one-ply, two-ply, three-ply or more. In all cases, the additive composition is desirably applied to the outer surface(s) of the product. The composition can be applied after the plies are brought together or prior to bringing the plies together. The individual plies can be layered or non-layered (homogeneous). In one embodiment, a three-ply tissue product may treated wherein the outer surfaces of the outer plies may include a treated portion as described above that includes a first composition for which transfer of the first composition to the skin of the user is desirable, such as, for example, a softener, lotion, and so forth. The middle ply may be treated with a second composition for which transfer of the second composition may not be desirable, such as, for example, an antiviral composition, an antibacterial composition, and so forth.

The add-on amounts, and the number, size, shape, and position of the treated portions, can be selected to maximize the overall benefit provided to the consumer while minimizing the total add-on amount. The term “add-on level” refers to the basis weight of additive composition in the treated portion, and is typically measured as a percentage of the substrate basis weight. The treated portion may be present on one or both surfaces of the tissue. The add-on level in the treated portion is desirably set as the level of the selected additive that provides a high degree of satisfaction on the part of the consumer. The actual basis weight values for the selected additive may need to be determined by comparing the consumer benefits obtained from a series of test tissue products that differ from one another only in the additive add-on amount, each having a uniform application of the additive deposited on one surface or both surfaces.

The number, size, shape and position of the treated portions on a particular tissue are selected so as to obtain the same or substantially the same consumer benefit as would be obtainable from a tissue having an additive applied to the entire surface. It should be readily appreciated that a wide variety of configurations of the shape and position of the treated portion may be possible. The specific size of the treated portion will depend upon the desired effect of the composition and the specific composition.

Another aspect of the invention relates to a method of making the tissue products described above. The method comprises the steps of: providing a tissue web and an additive composition; applying the additive composition to the tissue web in the treated portion at the appropriate add-on rate; and recovering from the rotogravure process a tissue product having the additive composition disposed in a treated portion.

One particularly beneficial method is to uniformly apply the composition to the surface of the tissue web within each of the zones by rotogravure printing, either direct or indirect (offset), because it is a very exact printing process and offers maximum control of the composition distribution and transfer rate. However, other application methods, such as flexographic printing, spraying, extruding, and the like can also be used. Typical of gravure printing, the additive composition in the treated portion may actually be present in a large number of small, spaced apart deposits on the tissue surface. These deposits are desirably uniformly positioned within each section of the treated portion but only cover part of the surface in each section. When viewed by the naked eye, the large number of small spaced-apart deposits appears to cover the entire surface, but in fact do not. The actual surface area coverage of the deposits can be from about 40 to about 80 percent, more specifically from about 50 to about 75 percent. For purposes of the present invention, the surface area of the treated portion includes the complete area circumscribed by the pattern of deposits, and not just the actual surface area coverage of the deposits.

Gravure printing is ideally suited to such an application by providing, for example, from about 10 to about 1000 deposits per lineal inch of surface, or from about 100 to about 1,000,000 deposits per square inch. Each deposit results from an individual cell on a printing roll, so that the density of the deposits corresponds to the density of the cells.

Gravure printing encompasses several well known engraving techniques, such as mechanical engraving, acid-etch engraving, electronic engraving and ceramic laser engraving. A suitable electronic engraved example for a primary delivery zone is about 200 deposits per lineal inch of surface, or about 40,000 deposits per square inch. By providing such a large number of small deposits, the uniformity of the deposit distribution is very high. Also, because of the large number of small deposits applied to the surface of the tissue, the deposits more readily re-solidify on the surface of the tissue where they are most effective in benefiting the user. As a consequence, a relatively low amount of the composition can be used to cover a large area.

The add-on rate is also determined by the volume of the gravure roll engraving. Typically, this is expressed in terms of the volume of the cells per square inch of engraved area. The volume in the primary delivery regions will deliver more additive composition than the volume in the supplementary delivery regions. The range of liquid cell volume for a primary delivery region, described in terms of cubic billion microns (CBM) per square inch, is suitably from about 0.5 to about 15 CBM per square inch, more specifically from about 1 to about 10 CBM per square inch, and still more specifically from about 1.5 to about 8 CBM per square inch. The range of liquid cell volume for a supplementary delivery region is suitably from 0.1 to about 10 CBM per square inch, more specifically from about 0.5 to about 8 CBM per square inch, and still more specifically from about 0.75 to about 6 CBM per square inch.

The additive composition or compositions can be applied to one or both outer surfaces of a tissue. The additive composition can be water-based or oil-based. Suitable water-based compositions include, but are not limited to, emulsions and water-dispersible compositions which can contain, for example, debonders (cationic, anionic or nonionic surfactants), or polyhydroxy compounds such as glycerin or propylene glycol. The basesheet could be treated with a bi-component system comprising a debonder and a polyhydroxy compound. Both components can be added separately or mixed together prior to being applied to the basesheet. In particular embodiments, the treated portions on the opposite sides of the tissue could comprise different additive compositions.

In particular embodiments, the tissue products are made by applying, on the surface(s) of the tissue, large numbers of individual deposits of a melted moisturizing/protective additive composition comprising a wax and an oil, and thereafter re-solidifying the composition to form a distribution, of solid deposits on the surface(s) of the tissue. Because the composition is a solid at room temperature and rapidly solidifies after deposition, it has less tendency to penetrate and migrate into the sheet. Compared to tissues treated with liquid formulations, this leaves a greater percentage of the added composition on the surface of the tissue where it can contact and/or transfer to the user's skin to provide a benefit. Furthermore, a lower add-on amount can be used in the treated portion to deliver the same benefit at lower cost because of the efficient placement of the composition substantially at the surface of the product.

The additive composition may comprise solidified deposits of a composition comprising from about 30 to about 90 weight percent oil, and from about 10 to about 40 weight percent wax, desirably also containing from about 5 to about 40 weight percent fatty alcohol, said composition having a melting point of from about 30° C. to about 70° C., more specifically from about 40° C. to about 60° C. For purposes herein, “melting point” is the temperature at which the majority of the melting occurs, it being recognized that melting actually occurs over a range of temperatures.

The amount of oil in the composition can be from about 30 to about 90 weight percent, more specifically from about 40 to about 70 weight percent, and still more specifically from about 45 to about 60 weight percent. Suitable oils include, but are not limited to, the following classes of oils: petroleum or mineral oils, such as mineral oil and petrolatum; animal oils, such as mink oil and lanolin oil; plant oils, such as aloe extract, sunflower oil and avocado oil; and silicone oils, such as dimethicone and alkyl methyl silicones.

The amount of wax in the composition can be from about 10 to about 40 weight percent, more specifically from about 10 to about 30 weight percent, and still more specifically from about 15 to about 25 weight percent. Suitable waxes include, but are not limited to the following classes: natural waxes, such as beeswax and carnauba wax; petroleum waxes, such as paraffin and ceresine wax; silicone waxes, such as alkyl methyl siloxanes; or synthetic waxes, such as synthetic beeswax and synthetic sperm wax.

The amount of fatty alcohol in the composition, if present, can be from about 5 to about 40 weight percent, and more specifically from about 10 to about 30 weight percent. Suitable fatty alcohols include alcohols having a carbon chain length of C14-C30, including acetyl alcohol, stearyl alcohol, behenyl alcohol, and dodecyl alcohol.

In order to better enhance the benefits to consumers, additional ingredients can be used. The classes of ingredients and their corresponding benefits include, without limitation, C10 or greater fatty alcohols (lubricity, body, opacity); fatty esters (lubricity, feel modification); vitamins (topical medicinal benefits); dimethicone (skin protection); powders (lubricity, oil absorption, skin protection); preservatives and antioxidants (product integrity); ethoxylated fatty alcohols; (wettability, process aids); fragrance (consumer appeal); lanolin derivatives (skin moisturization), colorants, optical brighteners, sunscreens, alpha hydroxy acids, natural herbal extracts, and the like.

The above additive composition may be applied to one or both outer surfaces of the tissue by heating the composition to a temperature above the melting point of the composition, for instance a melting point of from about 30° C. to about 70° C., thereby causing the composition to melt. The additive is then uniformly applied within the treated portion at the predetermined add-on amount by uniformly applying the melted composition to one or both surfaces of a tissue web in spaced-apart deposits. Thereafter, the deposits of the melted composition are re-solidified. Re-solidification of the deposits can occur almost instantaneously, without the need for external cooling means such as chill rolls, if the composition is heated to a temperature only slightly above or at the melting point of the composition. However, external cooling means such as chill rolls, either before or after the application of the melt, can be used if desired to accelerate re-solidification. Such instantaneous re-solidification tends to impede penetration of the composition into the tissue and retain it on the surface of the tissue, which is advantageous. For example, the temperature of the melted composition can advantageously be above the melting point about 10° C. or less, more specifically about 5° C. or less, and still more specifically about 2° C. or less. As the temperature of the melted composition approaches the melting point, the viscosity of the melted composition generally increases, which further enhances the tendency of the melted composition to be retained on the surface.

Surface additive compositions of the foregoing type comprising a wax and an oil are disclosed in International Patent Application PCT/US96/01243 published Aug. 15, 1996 and identified as WO 96/24722; and International Patent Application PCT/US96/01297 published Aug. 15, 1996 and identified as WO 96/24723; the disclosures of which are incorporated herein by reference.

The total tissue add-on amount of the additive composition can be from about 0.01 to about 40 weight percent, more specifically from about 0.3 to about 15 weight percent, and still more specifically from about 0.5 to about 10 weight percent, based on the weight of the tissue. The add-on amount will depend upon the desired effect of the composition on the product attributes and the specific composition. Generally, though, with respect to an additive composition of the foregoing type comprising a wax and an oil, the add-on amount is suitably from about 1 to about 35 weight percent, more specifically from about 3 to about 15 weight percent, and still more specifically from about 4 to about 10 weight percent, based on the weight of the tissue.

The additive composition may alternatively comprise a silicone compound. Suitable silicone compounds are those silicone compounds which provide a smooth, lubricated surface feel, desirably without smearing glass. Desirably the silicone compounds are present in an aqueous emulsion and/or solution for ease in handling and processing. A wide variety of such silicone compounds are known in the art. Specific suitable silicone compositions include, without limitation, polydimethyl siloxanes; mixtures of polydimethyl siloxanes and alkylene oxide-modified polydimethyl siloxanes; organomodified polysiloxanes; mixtures of cyclic- and non-cyclic-modified dimethyl siloxane; and the like. Number average molecular weights are generally about 10,000 or greater. Also suitable are aqueous mixtures of tetraethoxy silane, dimethyl diethoxy silane, and ethylene oxide/dimethyl siloxane copolymer. A desired composition contains about 5 weight percent tetraethoxy silane, about 5 weight percent dimethyl diethoxy silane, and about 2 weight percent ethylene oxide/dimethyl siloxane copolymer in water. In such silane mixtures, the ethylene oxide-dimethyl siloxane acts as a coupling agent to bind the silicone to the tissue sheet surface, thus retarding residue build-up on the contact surface and thereby reducing the greasy feeling associated with some lubricants.

Surface additive compositions of the foregoing type comprising a silicone compound are disclosed in U.S. Pat. No. 4,950,545 issued Aug. 21, 1990 and U.S. Pat. No. 5,227,242 issued Jul. 13, 1993, both to Walter et al.; the disclosures of which are incorporated herein by reference.

The total amount of silicone solids in the tissue sheet can be from about 0.1 to about 5 weight percent, based on the finished basis weight of the tissue sheet. Desirably the amount of the silicone compound is from about 0.5 to about 3 weight percent and most desirably from about 0.7 to about 2 weight percent. Amounts below 0.1 weight percent alone provide little benefit to the tissue in terms of softness improvement. Amounts above 5 weight percent may become economically unattractive.

The add-on amount of an additive composition comprising a silicone compound is suitably from about 0.1 to about 5 weight percent, more specifically from about 0.5 to about 3 weight percent, and still more specifically from about 0.7 to about 2 weight percent, based on the weight of the tissue.

The silicone compound can be incorporated into the facial tissue by any suitable means, including printing, spraying, dipping and the like. The silicone compound can be incorporated into the tissue sheet at any point in the tissue manufacturing process. Desirably the silicone compound is printed onto a dried tissue sheet between the base sheet manufacturing process and the final tissue product converting process. Printing provides precise control of the add-on amount of the silicone compound and places the silicone compound on the surface of the tissue in the treated portion.

For purposes herein, “tissue sheet” is a single ply sheet suitable for facial tissue, bath tissue, towels, napkins, or the like having a density of from about 0.04 grams per cubic centimeter to about 0.3 grams per cubic centimeter and a basis weight of from about 4 to about 40 pounds per 2880 square feet. Tensile strengths in the machine direction are in the range of from about 100 to about 5,000 grams per inch of width. Tensile strengths in the cross-machine direction are in the range of from about 50 to about 2500 grams per inch of width. Cellulosic tissue sheets of paper-making fibers are desirable, although synthetic fibers can be present in significant amounts.

The tissue sheet can be made in any suitable manner. In this regard, a variety of conventional papermaking apparatus may be used in the application of this invention, as they are known by persons of skill in the art. Conventional operations may be used with respect to the stock preparation, headbox, forming fabrics, web transfers, and through-air drying. For example, paper products utilized in the present invention can be made utilizing adhesive creping, wet creping, double creping, embossing, wet-pressing, air-pressing, through- air drying, creped through-air drying, uncreped through-air drying, as well as other steps known in the paper art. By way of illustration, various tissue making processes are disclosed in U.S. Pat. No. 5,607,551 issued Mar. 4, 1997 to Farrington and U.S. Pat. No. 5,667,636 issued Sep. 16, 1997 to Engel et al., which are incorporated herein by reference.

Referring to FIG. 3, a representative method of carrying out this invention is shown. FIG. 3 illustrates a tissue sheet 301 approaching a Yankee dryer 302 and being dislodged from the dryer with a creping blade 303. The dried creped tissue sheet 304 is passed to a heated rotogravure printing station comprising a backing roll 306 and an engraved roll 307, at which point the melted additive composition is applied to one surface of the tissue sheet. The treated tissue sheet is then wound into a roll 308 for subsequent converting operations.

During the printing operation, the melted composition to be applied to the tissue sheet is supplied by a heated supply tank 310 and pumped to a heated doctor application head 311 by a suitable metering pump. It is desirable to maintain constant temperature in the process. Accordingly, the melted composition may be continually circulated between the supply tank and the application head while maintaining an adequate amount in the reservoir. The heated doctor applicator head supplies the melted composition to the engraved roll 307, the surface of which contains a plurality of small cells that form the pattern to be printed on the final tissue product. As previously noted, the configuration and add-on rates of the cells are selected to provide the transfer volume necessary to achieve the desired tactile effect.

In operation the engraved roll 307 is loaded to the backing roll 306 to force the tissue web or sheet into contact with the engraved roll. The backing roll can be any material that meets the process requirements such as natural rubber, synthetic rubber or other compressible surfaces. Loading pressures can vary from approximately 5-50 pounds per lineal inch (roll to roll interference) to a gravure roll/backing roll gap of 0.008″ (no roll to roll contact).

In a further embodiment, the tissue sheet to be printed with the melted composition may be supplied from a parent roll. In such an off-line process, the printing operation is carried out independently of the tissue sheet manufacturing process. The sheet to be printed with the melted composition can be a single ply or it can be multiple plies. The resulting sheet is then wound into a roll for further converting operations. Even further, the additive may be printed on both sides of the tissue sheet using two printing stations in sequence. Two-sided printing is desirable when the effect of the composition is desired on both sides and/or the tissue sheet consists of two or more plies.

It is understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary constructions. The invention is shown by example in the appended claims.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7988824Dec 15, 2005Aug 2, 2011Kimberly-Clark Worldwide, Inc.Tissue product having a transferable additive composition
EP1732709A2 *Mar 30, 2005Dec 20, 2006Thi International, LLCApparatus and method for treating mulch
WO2008068653A1 *Oct 30, 2007Jun 12, 2008Kimberly Clark CoAdditive compositions for treating various base sheets
WO2008157132A1 *Jun 10, 2008Dec 24, 2008Dow Global Technologies IncAdditive compositions for treating various base sheets
Classifications
U.S. Classification162/134, 162/179, 162/172, 162/158
International ClassificationD21H17/14, D21H17/13, D21H23/22, D21H17/60, A47K10/16, D21H27/00, D21H27/02
Cooperative ClassificationA47K10/16, D21H27/008, D21H27/02
European ClassificationD21H27/02, D21H27/00D4, A47K10/16
Legal Events
DateCodeEventDescription
Apr 30, 2004ASAssignment
Owner name: KIMBERLY-CLARK WORLDWIDE, INC., WISCONSIN
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:REDDY, KIRAN KUMAR KARREM;REEL/FRAME:015294/0303
Effective date: 20040430