Stacked absorbent tissue paper product and method of forming same

Abstract

A method for forming a tissue paper product includes forming a wet web and drying the wet web. The method further includes calendering the dried web, forming a stack of tissue paper products from the compressed dried web, and packaging the stack of tissue paper products to form a packaged stack of tissue paper products. The packaged tissue paper product stack may have a packaging density of not less than 0.5 g / cm < 3 >.

Description

Cross Reference to Related Applications

[0001] This application is related to and has priority from U.S. Provisional Patent Application No. 63 / 520,395, filed August 18, 2023, which is incorporated by reference in its entirety for all purposes. BACKGROUND

[0002] To facilitate handling of thin tissue product sheets, absorbent thin tissue product sheets are often stacked together and then packaged for transport. After transport, the stacked thin tissue product sheets can be removed from the package and loaded into a dispenser from which an end user can remove individual thin tissue product sheets. Stacking and packaging absorbent thin tissue product sheets can allow for easier transport and handling, but also presents challenges.

[0003] Conventional methods of stacking and packaging absorbent thin tissue product sheets have drawbacks. For example, the volume of certain packages is relatively large, which results in increased transportation costs due to the relatively large volume each package occupies within a transport vehicle. However, reducing the volume of the package can adversely affect the absorbency and / or dispensability of the thin tissue product. Further, compressing stacked thin tissue product sheets with high pressure and then packaging the stacked thin tissue product sheets under pressure can reduce the absorbency and / or dispensability of the thin tissue product.

[0004] An improved packaged thin tissue product stack would be useful. For example, a packaged thin tissue product stack having a reduced volume while maintaining absorbency and / or dispensability would be useful. SUMMARY

[0005] Generally, the present disclosure relates to forming a thin tissue product including forming a fibrous web with a non-compressive dewatering such as through-air drying (TAD), uncreped through-air drying (UCTAD), or advanced thin paper molding technology (ATMOS), and then calendering the dewatered fibrous web to compress the fibrous web. The compressed fibrous web is then converted by folding to form a thin tissue product stack, which is then packaged. The packaged thin tissue product stack can have a bulk not less than zero point one five grams per cubic centimeter (0.15 g / cm 3 ) and not greater than zero point nine zero grams per cubic centimeter (0.90 g / cm 3). Thus, the packaged stack of tissue products can advantageously have a packing density that allows for more number of tissue products or the same number of tissue products to be shipped in a smaller volume relative to a packaged stack having a smaller packing density. The packaged stack of tissue products can also advantageously maintain absorbency and / or dispensability in combination with the packing density described above. For example, by calendering the dry fibrous web prior to packaging, the stack of tissue products can require less pressure to compress to the packing density described above. Surprisingly, calendering the dry fibrous web and then compressing the stack of tissue products can advantageously allow the packaged stack of tissue products to have the packing density described above while also advantageously maintaining absorbency and / or dispensability.

[0006] In one example embodiment, a method for forming a tissue product includes forming a tissue fibrous web using an uncreped through-air drying continuous process, calendering the tissue fibrous web to compress the tissue fibrous web, forming a stack of tissue products from the tissue fibrous web after calendering the tissue fibrous web, and packaging the stack of tissue products to form a packaged stack of tissue products. The packaged stack of tissue products has a packing density that is not less than 0.15 g / cm 3 and not greater than 0.90 g / cm 3 .

[0007] In another example embodiment, a method for forming a tissue product includes depositing fibers onto a forming surface to form a wet fibrous web, drying the wet fibrous web to form a dry fibrous web, calendering the dry fibrous web to form a compressed dry fibrous web, forming a stack of tissue products from the compressed dry fibrous web, and packaging the stack of tissue products to form a packaged stack of tissue products. The packaged stack of tissue products has a packing density that is not less than 0.15 g / cm 3 and not greater than 0.90 g / cm 3 .

[0008] In another example embodiment, a packaged stack of tissue products includes a plurality of tissue products stacked together and a package surrounding the plurality of tissue products. The plurality of tissue products and the package has a packing density that is not less than 0.15 g / cm 3 and not greater than 0.90 g / cm 3 . The tissue products of the plurality of tissue products have an absorbent capacity that is not less than 3 g / g of tissue and not greater than 10 g / g of tissue.

[0009] These and other features, aspects, and advantages of the present disclosure will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and serve to explain the principles of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0010] A complete and enabling disclosure of the present disclosure, directed to those ordinary skilled in the art, including its best mode, is set forth in the specification, which is to be taken in conjunction with the appended drawings.

[0011] Figure 1 is a perspective view of a stack of tissue products according to example aspects of the present disclosure;

[0012] Figure 2 is a schematic of a non-creped through-air dried tissue making process for forming a tissue web according to example aspects of the present disclosure;

[0013] Figure 3 is a schematic of a calendering process of a base sheet according to example aspects of the present disclosure;

[0014] Figure 4 is a schematic of a system through which a stack of tissue products can be sequentially transported according to example aspects of the present disclosure;

[0015] Figure 5 is a schematic of a stack of tissue products at an initial height according to example aspects of the present disclosure; and

[0016] Figure 6 is a schematic of an example stack of tissue products compressed from an initial height to a compressed height according to example aspects of the present disclosure. Figure 5

[0017] The repeated use of reference characters in the present specification and drawings is intended to represent the same or similar features or elements of the application. DETAILED DESCRIPTION

[0018] ​The present disclosure generally relates to forming compressed, absorbent, and / or dispensable folded tissue products. A wet fibrous web can be formed on a forming surface, the wet fibrous web can be at least partially dewatered, and the dewatered fibrous web can be dried. In example embodiments, various non-compression processes can be used to form the dried fibrous web, such as through-air drying (TAD), uncreped through-air drying (UCTAD), or advanced tissue molding technology (ATMOS). The dried fibrous web can be calendered to compress the dried fibrous web. The compressed dried fibrous web can then be further processed to form a tissue product stack having the compressed dried fibrous web. For example, the compressed dried fibrous web can be cut, folded, stacked, and packaged to form a tissue product stack having the compressed dried fibrous web. Compressing the dried fibrous web via calendering prior to folding, stacking, packaging, etc. can advantageously reduce the volume of the dried fibrous web while maintaining the absorbency and / or dispensability of the final tissue product. For example, due to the calendered dried fibrous web, the tissue product stack can require less pressure to compress the tissue product for packaging. In example embodiments, by calendering the dried fibrous web prior to packaging, the packaged tissue product stack can have a package density of not less than zero point one five grams per cubic centimeter (0.15 g / cm 3 ) and not greater than zero point nine zero grams per cubic centimeter (0.90 g / cm 3 ) while also maintaining the absorbency and / or dispensability of the final tissue product. Such a package density can advantageously allow for shipping a greater number of tissue products or having the same number of tissue products in a smaller volume relative to a packaged stack having a smaller package density.

[0019] One of ordinary skill in the art will appreciate that the discussion is merely provided for the purpose of summarizing example embodiments and is not intended to limit the broader aspects of the disclosure.

[0020] When introducing elements of the present disclosure or the preferred embodiments thereof, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and allow for elements or events that would otherwise exclude, e.g., "comprising" is defined to include "consisting." Similarly, the term "or" is intended to be inclusive (i.e., "A or B" is intended to mean "A or B or both"). As used throughout the specification and claims, the approximate language is applied to modify any quantitative representation that could permit an insubstantial variation from the recited meaning without resulting in a change in the basic function to which such quantitative representation is directed. Accordingly, a value modified by one or more terms such as "about," "approximately," and "substantially" is not limited to the precise value specified. In at least some instances, the approximate language can correspond to the precision of an instrument used to measure the value. For example, the approximate language can refer to within ten percent (10%) of the magnitude.

[0021] Definitions :

[0022] As used herein, the term "base sheet" refers to a tissue paper fibrous web formed by any one of the papermaking processes described herein that has not yet been subjected to further processing such as embossing, calendering, treatment with softening or moisturizing compositions, perforating, plaiting, folding, or winding into individual roll products.

[0023] As used herein, the term "tissue paper product" refers to a product made from a base sheet and includes toilet tissue, facial tissue, paper towel, industrial wiper, food service wiper, napkin, medical pad, and other similar products.

[0024] As used herein, the terms "tissue paper fibrous web" or "tissue paper sheet" refer herein to a web of cellulosic fibers suitable for making or use as cosmetic paper, toilet tissue, paper towel, napkin tissue, and the like. The tissue paper fibrous web can be layered or unlayered, uncreped, and can be composed of a single ply or multiple plies. The tissue paper fibrous web described above is preferably made from natural cellulosic fiber sources such as hardwood, softwood, and non-wood based, but can also include a significant amount of recycled fibers, sized fibers or chemically modified fibers, or synthetic fibers.

[0025] As used herein, the term "ply" refers to a discrete tissue paper fibrous web used to form a tissue paper product. The individual plies can be arranged side-by-side to one another.

[0026] As used herein, the term "layer" refers to a plurality of fiber layers, chemical treatment layers, and the like within a ply. A "layered tissue paper fibrous web" generally refers to a tissue paper fibrous web formed from two or more layers of aqueous papermaking furnish. In some cases, the aqueous papermaking furnishes forming the two or more layers include different fiber types and / or can be manufactured by different manufacturing techniques.

[0027] As used herein, the term "tissue paper" refers to a fibrous web having a structure of individual fibers that are interlaced with one another but not in an identifiable manner as in a knitted or woven fabric. Nonwoven materials include, for example, carded fibrous webs, wet-laid fibrous webs, air-laid fibrous webs, foam-formed fibrous webs, and the like.

[0028] As used herein, the term "pulp" generally refers to a plurality of cellulosic fibers that have been treated by a pulping process that have become individualized and elongated in shape with an apparent length greater than an apparent width. The pulp fibers can be fibrillated and can have a measurable freeness.

[0029] As used herein, the term “basis weight” generally refers to the conditioning weight of tissue paper per unit area and is typically expressed in grams per square meter (gsm). While the basis weight of tissue paper products prepared according to this disclosure may vary, in some example embodiments the product has a basis weight greater than ten (10) gsm, such as greater than twenty (20) gsm, such as greater than about thirty (30) gsm, such as about ten (10) to about fifty (50) gsm, such as about fifteen (15) to about forty (40) gsm, such as about twenty (20) to about thirty (30) gsm.

[0030] As used herein, the term "longitudinal" or "MD" generally refers to the direction in which the thin paper fiber web or product is produced. The term "transverse" or "CD" refers to the direction perpendicular to the longitudinal direction.

[0031] As used herein, the term “thickness” refers to the representative thickness of a single sheet of absorbent lint fiber web, measured according to TAPPI Test Method T402 using a ProGage 500 thickness gauge (Thwing-Albert Instrument Company, West Berlin, NJ). The thickness of the absorbent lint fiber web comprising one or more layers is the thickness of a single sheet comprising all layers of absorbent lint fiber web. The micrometer has an anvil diameter of 2.22 inches (56.4 mm) and an anvil pressure of 132 g / cm² (per 6.45 cm²) (2.0 kPa). Sheet “bulkness” is calculated as the quotient of the dry sheet thickness divided by the dry basis weight.

[0032] Stacked packaged tissue product :

[0033] Figure 1 This is a perspective view of a package 10 containing stacked tissue paper products 20 according to an example embodiment of this subject matter. As shown, the package 10 contains a plurality of tissue paper products 20. The tissue paper products 20 are folded together. The tissue paper products 20 contained in the package 10 may vary depending on the specific application. For example, the tissue paper products 20 may include facial tissues, toilet paper, paper towels, napkins, industrial wipes, etc.

[0034] Generally, tissue paper product 20 includes cellulose fibers, such as cork fibers and / or hardwood fibers. Tissue paper product 20 may also or optionally include secondary or recycled cellulose fibers and mixtures thereof. Particularly suitable hardwood fibers include eucalyptus fibers and maple fibers. Cork fibers particularly suitable for manufacturing tissue paper product 20 include northern cork kraft paper fibers. Tissue paper product 20 may include cellulose fibers in an amount greater than about fifty percent (50%) by weight, such as greater than about eighty percent (80%) by weight. For example, in one example embodiment, tissue paper product 20 may substantially comprise pulp fibers. In one example embodiment, tissue paper product 20 may also include synthetic fibers, such as fibers made from thermoplastic polymers. Tissue paper product 20 may, for example, include pulp fibers combined with synthetic fibers. Synthetic fibers may be present in an amount less than about fifteen percent (15%) by weight, such as from about one percent (1%) to about ten percent (10%) by weight.

[0035] As described above, in the example embodiments, the tissue paper product 20 may substantially comprise pulp fibers, i.e., about 100% (100%) of pulp fibers by weight. In some example embodiments, the tissue paper product 20 may comprise recycled or reused cellulose fibers as well as virgin cellulose fibers. For example, the tissue paper product 20 may comprise recycled cellulose fibers, and the recycled cellulose fibers may be present in an amount not less than about 90% (90%) and not more than about 100% (100%) by weight. Furthermore, the tissue paper product 20 may comprise virgin cellulose fibers, and the virgin cellulose fibers may be present in an amount greater than 0% (0%) and not more than about 10% (10%) by weight. The virgin cellulose fibers may be cork pulp fibers, such as Northern Cork Kraft Paper Fiber. As can be seen from the above, in some example embodiments, the tissue paper product 20 may substantially comprise recycled or reused cellulose fibers, such as about 100% (100%) of recycled or reused cellulose fibers by weight. In other example embodiments, the tissue paper product 20 may include recycled or reused cellulose fibers as well as virgin cellulose fibers. In some example aspects, the tissue paper product 20 having virgin cellulose fibers may advantageously provide improved absorbency compared to a tissue paper product 20 without virgin cellulose fibers.

[0036] The tissue paper product 20 can be made from a uniform fiber formulation, or it can be formed from a layered fiber formulation that produces layers within each sheet. The layered fiber web can be formed using equipment known in the art, such as a multilayer headbox.

[0037] The packaged tissue paper product 20 can typically be formed using any of a variety of papermaking processes. In one example embodiment, the tissue paper product 20 may be formed as a wet-laid fiber web or a foam-laid fiber web. Methods that can be used to form the tissue paper product 20 include air drying, adhesive creping, wet creping, double creping, embossing, and any other suitable method or technique.

[0038] Thin cotton paper products typically have a density greater than approximately 3 cubic centimeters per gram (3cm²). 3 / g), such as approximately five cubic centimeters per gram (5cm³ / g). 3 / g) to approximately 15 cubic centimeters / gram (15cm) 3 The bulk density is 1 / g. The tissue paper product 20 can be substantially dry, that is, the tissue paper product 20 can contain only ambient moisture.

[0039] The number of tissue paper products 20 included in the package 10 may vary depending on the specific application. In one example embodiment, the package 10 may contain at least about fifty (50) tissue paper products 20. For example, the package 10 may contain about one hundred (100) tissue paper products 20 to about one thousand (1000) tissue paper products 20, such as about two hundred (200) tissue paper products 20 to about five hundred (500) tissue paper products, such as about two hundred and fifty tissue paper products 20.

[0040] like Figure 1 As shown, the tissue paper product 20 in package 10 can be held together by package 30. Package 30 may include cardboard or plastic film. Figure 1 As shown, in one example embodiment, the package 30 may be in the form of a sleeve or strap wrapping around the already stacked tissue paper products 20. In this example embodiment, the package 30 wraps around the tissue paper products 20 to include an open end on one side and an open end on the opposite side. However, in an alternative example embodiment, the tissue paper products 20 may be completely enclosed within the package 30.

[0041] As described above, in the example embodiments, the package 30 can compress the tissue paper product 20 together. For example, the package 30 can compress the tissue paper product 20 together such that the compressed stack height is at least about 10 percent (10%) smaller than the uncompressed stack height. In various example embodiments, the compressed stack height can be at least about 20 percent (20%) smaller than the uncompressed stack height, at least about 30 percent (30%) smaller than the uncompressed stack height, and in one example embodiment, even at least about 50 percent (50%) smaller than the uncompressed stack height. In a particular example embodiment, the tissue paper product 20 can be compressed such that the compressed stack height can be from about 20 percent (20%) to about 40 percent (40%) smaller than the uncompressed stack height.

[0042] The amount of force applied by the packaging 30 to the tissue paper product 20 can vary depending on the specific application. In one example embodiment, the packaging 30 may apply a force greater than about 0.75 psi, such as a force greater than about 1 psi. For example, the packaging 30 may apply a force from about 0.75 psi to about 1.5 psi.

[0043] In one example implementation, packaging 30 may include various printed materials. For example, packaging 30 may include trademarks and product information. Furthermore, packaging 30 may include instructions teaching users how to refill the appropriate dispenser. The printed materials may also include advertisements regarding sheet quality, dispensing benefits, and environmental benefits.

[0044] like Figure 1As shown, package 10 may define a longitudinal direction O, a transverse direction T, and a lateral direction A. The longitudinal direction O, transverse direction T, and lateral direction A may be perpendicular to each other. Package 10 may have a length L along the longitudinal direction O. Furthermore, package 10 may extend along the longitudinal direction O between a first end portion 11 and a second end portion 12, and the length L of package 10 may be defined between the first end portion 11 and the second end portion 12 of package 10. The first end portion 11 and the second end portion 12 of package 10 may be positioned opposite each other on package 10 along the longitudinal direction O. Package 10 may also have a height H along the transverse direction T. Furthermore, package 10 may extend along the transverse direction T between a top portion 13 and a bottom portion 14, and the height H of package 10 may be defined between the top portion 13 and the bottom portion 14 of package 10. The top portion 13 and the bottom portion 14 of package 10 may be positioned opposite each other on package 10 along the transverse direction T. Package 10 may also have a width W along the lateral direction A. Furthermore, the package 10 may extend along a lateral direction A between a first side portion 15 and a second side portion 16, and the length L of the package 10 may be defined between the first side portion 15 and the second side portion 16. The first side portion 15 and the second side portion 16 of the package 10 may be positioned opposite each other on the package 10 along a lateral direction A.

[0045] In the example embodiment, the tissue paper products 20 can be stacked within the package 30 along the transverse direction T. Therefore, for example, the length of each tissue paper product 20 along the longitudinal direction O can also correspond to the length L of the package 10. Furthermore, the width of each tissue paper product 20 along the lateral direction A can also correspond to the width W of the package 10. Conversely, the height of each tissue paper product 20 along the transverse direction T can be significantly less than the height H of the package 10. However, the height H of the package 10 can approximately correspond to the total height of the tissue paper products 20 along the transverse direction T.

[0046] It should be understood that the values ​​of the length L, width W, and height H of the package 10 may vary depending on the specific application. In an example embodiment, the length L of the package 10 may be not less than 10 cm, not less than 15 cm, such as not less than 20 cm, and the length L of the package 10 may be not greater than 60 cm, such as not greater than 45 cm, such as not greater than 35 cm. In an example embodiment, the width W of the package 10 may be not less than 5 cm, not less than 7 cm, such as not less than 10 cm, and the width W of the package 10 may be not greater than 20 cm, such as not greater than 15 cm, such as not greater than 10 cm. In the example implementation, the height H of the package 10 may be not less than 10 cm, not less than 15 cm, such as not less than 20 cm, and the height H of the package 10 may be not greater than 60 cm, such as not greater than 45 cm, such as not greater than 35 cm. It should be understood that such dimensions of the package 10 are provided by way of example.

[0047] The tissue paper product 20 can be compressed within the package 10. Furthermore, as described above, the package 30 can compress the tissue paper product 20 together, resulting in a smaller stack height after compression than the uncompressed stack height. Therefore, the package 10 can be configured to facilitate transport, for example, by allowing the package 10 to contain more tissue paper product 20 or the same quantity of tissue paper product within a smaller volume than a conventional package with a lower packing density, due to the packaging density of the package 10 described below. Moreover, although the tissue paper product 20 is compressed when contained within the package 30, it retains absorbency and / or dispensability when removed from the package 10.

[0048] In the example implementation, the tissue paper product 20 may be compressed within the package 10 to provide a packaging density for the package 10. As used herein, the term "packaging density" may be defined as the weight of the package 10 divided by the packaging volume of the package 10, where the packaging volume corresponds to the product of the length L, width W, and height H of the package 10. The calculation of packaging density is also described in more detail in the "Test Methods" section below.

[0049] The packaging density of package 10 can be not less than 0.15 g / cm³ (0.15 g / cm³). 3 And not greater than 0.90 g / cm³ (0.90 g / cm³). 3 ), such as not exceeding 0.70 g / cm³ (0.70 g / cm³). 3), such as not exceeding 0.50 g / cm³ (0.50 g / cm³). 3 ), such as not exceeding 0.30 g / cm³ (0.30 g / cm³). 3 ), such as not exceeding 0.20 g / cm³ (0.20 g / cm³). 3 Compared to conventional packaging with a lower packaging density, the packaging density of the aforementioned packaging 10 advantageously provides more tissue paper product 20 within the same volume. Furthermore, as stated above, the packaging density of packaging 10 can provide more tissue paper product 20 or the same quantity of tissue paper product within a smaller volume while maintaining absorbency and / or dispensability. Surprisingly, the packaging density of packaging 10 can be achieved without substantially reducing the absorbency and / or dispensability of the tissue paper product 20.

[0050] In the example implementation, after the tissue paper product 20 is removed from the package 30, the tissue paper product 20 may have a desired absorbency. As used herein, the term "absorbency" can be defined as the amount of water absorbed by the tissue paper sheet, expressed as grams of water absorbed per gram of tissue paper (dry weight). The calculation of absorbency is also described in more detail in the "Test Methods" section below.

[0051] The absorbency of the tissue paper product 20 can be no less than 3 g water / g tissue paper (3 g / g) and no more than 10 g water / g tissue paper (10 g / g), such as no less than 3.25 g water / g tissue paper (3.25 g / g) and no more than 7 g water / g tissue paper (7 g / g), such as no less than 3.5 g water / g tissue paper (3.5 g / g) and no more than 6 g water / g tissue paper water (6 g / g). Compared to conventional tissue paper products with smaller absorbency after being removed from compressed packaging, the absorbency of the aforementioned tissue paper product 20 can advantageously provide excellent absorbency characteristics. Furthermore, as mentioned above, the absorbency of the tissue paper product 20 can withstand the compression of the packaging 30. Surprisingly, the absorbency of the tissue paper product 20 can be achieved in conjunction with the packaging density of the packaging 10. Furthermore, in the example implementation, the tissue paper product 20 may have the above-mentioned absorbent capacity, wherein the basis weight is not less than fifteen (15) gsm to about forty (40) gsm, such as about twenty-five (25) gsm.

[0052] Forming system and method :

[0053] Ideally, the tissue paper product may be composed of a tissue paper fiber web. A suitable tissue paper fiber web for this purpose can be manufactured using any method that produces an elastic structure. Such methods include crease-free air-drying. Ideally, the tissue paper substrate may be a crease-free air-drying tissue paper fiber web. Exemplary methods for preparing crease-free air-drying tissue paper are described in U.S. Patent Nos. 5,607,551, 5,672,248, 5,593,545, 6,083,346, and 7,056,572, all of which are incorporated herein by reference. However, it should be understood that in other exemplary embodiments, the tissue paper product may be formed using other non-compression dehydration processes. For example, the tissue paper fiber web may be formed using air-drying (TAD) or advanced tissue paper molding technology (ATMOS). An example TAD process is described in U.S. Patent No. 5,853,547, which is incorporated herein by reference. Example ATMOS processes are described in U.S. Patents Nos. 7,744,726, 7,550,061, and 7,527,709, all of which are incorporated herein by reference.

[0054] Now for reference Figure 2 A method for manufacturing a ventilated and dried substrate is shown. A double-web forming device with a papermaking headbox 34 (such as a layered headbox) is shown, which injects or deposits a stream 36 of an aqueous suspension of papermaking fibers onto a forming fabric 38 located on a forming roll 39. The forming fabric 38 is used to support the newly formed wet web and convey it downstream of the process when the web is partially dehydrated to a consistency of approximately ten (10)% dry weight. Further dehydration of the wet web can be performed, for example by vacuum suction, while the wet web is supported by the forming fabric.

[0055] The wet fiber web is then transferred from the forming fabric 38 to the transfer fabric 40. In one example embodiment, the transfer fabric 38 may travel at a slower speed than the forming fabric 38 in order to impart increased stretch to the fiber web. This is often referred to as a “rapid” transfer. The relative speed difference between the two fabrics can be from zero (0) to sixty percent (60), more specifically from about fifteen percent (15) to forty-five percent (45). Preferably, the transfer is carried out with the aid of a vacuum boot 42 and a fixed gap or void between the forming fabric 38 and the transfer fabric 40, or with the aid of a kiss transfer, to avoid compressing the wet fiber web.

[0056] Then, using vacuum transfer rollers 46 or vacuum transfer boots, optionally again employing the fixed-gap transfer as described above, the wet fiber web is transferred from transfer fabric 40 to ventilated drying fabric 44. Ventilated drying fabric 44 may travel relative to transfer fabric 40 at approximately the same speed or a different speed. If desired, ventilated drying fabric 44 may run at a slower speed to further enhance stretching. The transfer can be performed with vacuum assistance to ensure that the sheet deforms to conform to ventilated drying fabric 44, thereby producing the desired volume and imparting a three-dimensional morphological pattern to the fiber web.

[0057] The vacuum level used for transferring the web can be from about 75 (75) to about 380 (380) mmHg, preferably about 125 (125) mmHg. In addition to or as an alternative to drawing the web onto the next fabric using vacuum, a vacuum boot (negative pressure) can be supplemented or replaced by using positive pressure from the opposite side of the web to blow the web onto the next fabric. Furthermore, one or more vacuum rollers can be used in place of one or more vacuum boots.

[0058] When supported by a ventilated drying fabric, the fiber web is dried through a ventilated dryer 48 to approximately 94 percent (94%) or higher consistency, and then transferred to a carrier fabric 50. The dried substrate 52 is conveyed to a reel 54 using the carrier fabric 50 and optionally a carrier fabric 56. An optional pressure guide roller 58 may be used to facilitate the transfer of the fiber web from the carrier fabric 50 to the fabric 56. In one example embodiment, as... Figure 2 The spool 54 shown can operate at a slower speed than the fabric 56 during the rapid transfer process used to build the body into the thin paper fiber web 52. For example, the relative speed difference between the spool 54 and the fabric 56 can be from about five percent (5) to about twenty-five percent (25), and particularly from about twelve percent (12) to about twenty percent (20), such as about eighteen percent (18). The rapid transfer at the spool 54 can occur alone or in combination with an upstream rapid transfer process, such as between the forming fabric 38 and the transfer fabric 40.

[0059] The smoothness and flexibility of substrate 52 can be improved using roll calendering or subsequent offline calendering. For example, as... Figure 2 As shown, the thin cotton paper fiber web 52 can be conveyed through one or more fixed-gap calendering rollers 60 before being wound onto the reel 54. Therefore, the dried substrate 52 can be calendered to compress it.

[0060] As those skilled in the art will understand, the compression of the dried substrate 52 can be performed by a variety of methods and mechanisms. For example, in Figure 3In this process, the drying substrate 52 can pass through one or more rollers or roller gaps 62, 64, which are configured to compress and smooth the surface of the material. The drying substrate 52 can be compressed such that the thickness of the drying substrate 52 is reduced from an initial thickness TH1 to a compressed thickness TH2. The difference between the initial thickness TH1 and the compressed thickness TH2 can vary depending on the specific application. In an example embodiment, the difference between the initial thickness TH1 and the compressed thickness TH2 may not exceed 300 micrometers (300µm), such as not exceeding 200 micrometers (200µm), such as not exceeding 100 micrometers (100µm).

[0061] The calendering effect on the dry substrate 52 can vary depending on the temperature, the applied pressure, and the duration of the pressure. Calendering can be performed at ambient temperature or at elevated temperatures. Suitable calendering pressures can be from about fifty (50) to about 1,400 (1,400) pounds per linear inch (pli). Suitable temperatures can be from about twenty degrees Celsius (20°C) to about two hundred and forty degrees Celsius (240°C). The duration of calendering can be varied in combination with the roll gap pressure to produce the desired compression for the dry substrate 52.

[0062] like Figure 2 The method shown in the example embodiments can be a continuous production process. Therefore, for example, the fiber web can be continuous between the various components described above, and the fiber web may not be wound onto a spool and not conveyed to another line between components. Specifically, the dried substrate 52 can be calendered before the spool 54. Therefore, during this method, the fiber web can move continuously between the headbox, the ventilated dryer, and the calender. In other example embodiments, the roll of dried substrate can be transferred to a separate calender or a folding device with a calender to compress the substrate before folding and packaging. Therefore, calendering can be a process discontinuous or separate from the formation of the substrate. Furthermore, in some example embodiments, both calendering in a continuous production process of the dried fiber web and calendering separate or separate from the production process can be used to compress the dried fiber web.

[0063] After forming and calendering, the fiber web can be transformed into a stack of packaged tissue paper products, such as packaging 10, through other processes (such as embossing, printing, cutting, slicing, folding, compression, and packaging). For example, see reference... Figure 4 According to the example aspect, system 70 can be configured to convert tissue paper products into packaged tissue paper product stacks, such as package 10. System 70 may include a folding assembly 72, a stacking assembly 74, a compression assembly 76, and a packaging assembly 78. Tissue paper products, such as tissue paper product 20 ( Figure 1The process can proceed sequentially through: a folding component 72, for example, in which each piece of tissue paper is folded; a stacking component 74, for example, in which the folded tissue papers are stacked into a tissue paper stack; a compression component 76, for example, in which the tissue paper stack is compressed to reduce the height of the tissue paper stack; and a packaging component 78, for example, in which the compressed tissue paper stack is packaged.

[0064] refer to Figure 5 and Figure 6 The stack of thin tissue paper products 20 from the stacking assembly 74 can have, for example, the stacking of the thin tissue paper products 20. Figure 5 The initial height is shown. Compression assembly 76 can displace the stack of tissue paper product 20 from the initial height shown. Figure 5 The initial height shown is compressed to, as Figure 6 The compression height is shown. Packaging 30 can be applied to the stack of tissue paper product 20 to maintain the desired compression height. Figure 6 The compression height is shown. The compression of the stack of tissue paper products 20 can vary depending on the specific application. For example, the compression component 76 can compress the stack of tissue paper products 20 such that the compression height is at least about 10 percent (10%) less than the initial height, such as at least about 20 percent (20%) less than the initial height, such as at least about 30 percent (30%) less than the initial height, and even at least about 50 percent (50%) less than the initial height in one example embodiment. In a particular example embodiment, the compression component 76 can compress the stack of tissue paper products 20 such that the compression height is about 20 percent (20%) to about 40 percent (40%) less than the initial height.

[0065] It should be understood that, such as Figure 5 and Figure 6 The compression component 76 shown is provided by way of example only. Other methods and mechanisms may be used to cut, fold, compress, package, and otherwise convert calendered fiber webs into a packaged stack of tissue paper products, such as package 10. For example, the compression apparatus described in U.S. Patent No. 11,542,048, which is incorporated herein by reference, may be used to compress a stack of tissue paper products 20.

[0066] Test method :

[0067] Dry basis weight

[0068] The dry basis weight of the material forming the stacked tissue paper products can be obtained using the current ASTM standard D646-96 (2001), the standard test method for basis weight (mass per unit area) of paper and paperboard, or an equivalent method.

[0069] Packaging density

[0070] Generally, packaging density can be calculated in the manner described in U.S. Patent No. 11,542,048, which is incorporated herein by reference.

[0071] As defined above, the packaging of tissue paper products has a length L, width W, and height H that are perpendicular to each other. The stacked volume is determined by calculating the product of length L, width W, and height H (i.e., L × W × H).

[0072] During the 48-hour period, the sample stacks were conditioned to 23 degrees Celsius and 50 percent relative humidity.

[0073] If the density to be measured is the density of free stacking, the following height measurement procedure should be followed:

[0074] To determine the height H, the stack is positioned on a generally horizontal support surface, which is configured such that the height H of the stack extends in a generally vertical direction. At least one side of the stack can abut against the vertically extending support to ensure that the stack as a whole extends in a generally vertical direction. The height H of the stack is the vertical height measured from the support surface. A measuring rod, kept parallel to the horizontal support surface and parallel to the width W of the stack, is lowered toward the stack, and the vertical height of the rod when it contacts the stack is recorded. The measuring rod is lowered toward the stack at three different locations along the length L of the stack. The first location should be at the middle of the stack, i.e., 0.5 L. The second location should be approximately two centimeters (2 cm) from the first end portion 11 (measured along length L), and the third location should be approximately two centimeters (2 cm) from the second end portion 12 (measured along length L). The height H of the stack is determined as the average of three height measurements taken at the three different locations.

[0075] It should be understood that when the above height measurement method is performed, and when the stack is not perfectly rectangular but, for example, the end surfaces bulge outwards, the height H will correspond to the maximum height of the stack.

[0076] If the density to be measured is the density of the stack when it is included in the packaging, then the height measurement procedure described above is performed when the stack is included in the packaging. If the packaging material has a thickness that significantly affects the measurement results, the thickness of the packaging material can be measured after it has been removed from the stack, and the value obtained during the height measurement can be adjusted accordingly.

[0077] The length L and width W of the stack are determined by opening the stack and measuring the length L and width W of the tissue paper product within the stack. Edges and / or folds in the tissue paper material will provide necessary guidance for performing the measurements of length L and width W. It should be understood that the length and width of the stack may change during compression and relaxation of the stack. However, such changes are considered insignificant for the results desired herein. Instead, the length L and width W of the stack are considered constant and identical to those measured on the tissue paper product.

[0078] The weight of the stack is measured by weighing it to one decimal place (0.1 g) using a suitable, calibrated scale. To determine the density of the stack within its packaging, the packaging is removed before weighing the stack.

[0079] The calculated stack volume (L×W×H) is divided by the measured stack weight to calculate the packing density. Therefore,

[0080] .

[0081] Absorption capacity

[0082] As described above, absorbance capacity is a measure of the amount of water absorbed by a sheet of tissue paper, expressed as grams of water absorbed per gram of tissue paper (dry weight). Specifically, vertical absorbance capacity is determined by cutting the sheet of the product to be tested into a square measuring 100 mm × 100 mm (±1 mm). The resulting test sample is weighed to two decimal places (0.01 g) and recorded as “dry weight.” The sample is attached to a 3-point clamping device and suspended from one corner of the device, with the opposite corner lower than the rest of the sample. The sample and clamp are then placed in a dish of water and immersed for 3 minutes (±5 seconds). The water should be distilled or deionized water at 23±3°C. At the end of immersion, the sample and clamp are removed from the water. The clamping device should minimize the influence of clamping area and pressure on the test results. Specifically, the clamping area should be only large enough to hold the sample, and the pressure should be only sufficient to hold the sample while minimizing the amount of water removed from the sample during clamping. Allow the sample to drain for 3 minutes (±5 seconds). At the end of the drainage, remove the sample by holding the weighing pan under the sample and releasing it from the clamping device. Then weigh the wet sample to two decimal places (0.01 g) and record this value as “wet weight”.

[0083] The difference between the measured wet weight and the measured dry weight can be divided by the measured dry weight to calculate the absorption capacity. Therefore,

[0084] .

[0085] At least five (5) repeated measurements were performed on representative samples from the same roll or box of products to obtain the average absorption capacity.

[0086] Examples :

[0087] Qualitative tests were performed on samples of folded paper towels compared to several commercially available folded paper towels. Table 1 lists the commercially available folded paper towels used for comparison.

[0088]

[0089] The sample of this invention corresponds to Scott ® The formulation and corresponding forming process of 1804 tissue paper include calendering to compress and dry the fiber web, and providing approximately 0.18 g / cm³ (0.18 g / cm³) of thin tissue paper before unpacking. 3 Packaging density. (Scott) ® The 1804 tissue paper sample corresponds to the uncalendered control sample below. Before unpacking, the packing density of the thin tissue paper clips in commercially available folded tissues is less than 0.15 g / cm³. 3 ).

[0090] The test involved one hundred and twenty (120) participants. Each participant evaluated a sample of the present invention and five samples of commercially available folded paper towels in the following manner: Participants were asked to wash and dry their hands in the same manner they would normally do in a public restroom, and then answer questions about each sample. During each sample test, participants applied cosmetics to their hands and distributed dirt to their palms and backs of their hands. Each participant was provided with a soap pump, and they washed their hands in the normal manner. Participants were asked to remove the sample from the dispenser and dry their hands. Participants were then asked to rate the degree to which the sample dried their hands. The results are summarized below as the percentage of participants for the preferred sample of the present invention compared to commercially available samples, and the percentage of participants for the preferred comparative samples compared to other commercially available samples.

[0091]

[0092] As can be seen from the above, the samples of the present invention provide similar drying and therefore absorption properties to the comparative uncalcined samples. Furthermore, the calcination of the dried fiber web does not negatively affect the drying and therefore absorption properties in a significant manner. The samples of the present invention also provide absorption properties comparable to or better than commercially available samples.

[0093] Participants were also asked about the ease with which they could obtain the required amount of sample from the dispenser. The results are summarized below as the percentage of participants for the preferred sample of the invention compared to commercially available samples, and the percentage of participants for the preferred comparative sample compared to other commercially available samples.

[0094]

[0095] As can be seen from the above, the samples of the present invention provide improved dispensing quality compared to the comparative uncalendered samples. Therefore, calendering of the dried fiber web does not detrimental to the dispensing of the samples, but rather improves it. Without wishing to be bound by any particular theory, it is believed that reducing the compression force required to achieve the provided packaging density by calendering the fiber web before compression reduces interference between adjacent sheets. The samples of the present invention also consistently provide better dispensing performance compared to all commercially available samples.

[0096] Participants were also asked if they experienced any difficulty in removing the sample from the dispenser. All participants indicated that removing the sample from the dispenser was not difficult.

[0097] These and other modifications and variations of the invention can be practiced by those skilled in the art without departing from the spirit and scope of the invention, which are more specifically set forth in the appended claims. Furthermore, it should be understood that aspects of the various embodiments are interchangeable in whole or in part. Moreover, those skilled in the art will understand that the foregoing description is merely illustrative and is not intended to limit the invention further described in the appended claims.

[0098] Example embodiments

[0099] First example implementation: A method for forming a tissue paper product, the method comprising: forming a tissue paper fiber web using a crepe-free ventilated drying continuous process; calendering the tissue paper fiber web to compress the tissue paper fiber web; forming a tissue paper product stack from the tissue paper fiber web after calendering; and packaging the tissue paper product stack to form a packaged tissue paper product stack, wherein the packaged tissue paper product stack has a packaging density of not less than 0.15 g / cm³ and not more than 0.90 g / cm³.

[0100] Second example implementation: According to the method described in the first example implementation, the packaging density of the stacked tissue paper products is less than 0.20 g / cm³.

[0101] Third example implementation scheme: According to the method described in the first example implementation scheme or the second example implementation scheme, the basis weight of the thin cotton paper fiber web is not less than one gram per square centimeter and not more than five grams per square meter.

[0102] Fourth example implementation: The method according to any one of the first to third example implementations, wherein the stacked tissue paper products of the packaged tissue paper products have an absorption capacity of not less than 3 grams of water per gram of tissue paper and not more than 10 grams of water per gram of tissue paper.

[0103] Fifth example implementation: A stack of packaged tissue paper products formed according to any one of the first to fourth example implementations.

[0104] Sixth Example Implementation: A method for forming a tissue paper product, the method comprising: depositing fibers onto a forming surface to form a wet fiber web; drying the wet fiber web to form a dry fiber web; calendering the dry fiber web to form a compressed dry fiber web; forming a tissue paper product stack from the compressed dry fiber web; and packaging the tissue paper product stack to form a packaged tissue paper product stack, wherein the packaged tissue paper product stack has a packaging density of not less than 0.15 g / cm³ and not more than 0.90 g / cm³.

[0105] Seventh Example Implementation: The method according to the sixth example implementation, wherein the packaging density of the stacked tissue paper products is less than 0.20 g / cm³.

[0106] Eighth Example Implementation: The method described in the sixth or seventh example implementation, wherein the basis weight of the compressed dry fiber web is not less than one gram per square centimeter and not more than five grams per square meter.

[0107] Ninth Example Implementation: The method according to any one of the sixth to eighth example implementations, wherein the stacked tissue paper products of the packaged tissue paper products have an absorption capacity of not less than three grams of water per gram of tissue paper and not more than ten grams of water per gram of tissue paper.

[0108] Tenth Example Implementation: The method according to any one of the sixth to ninth example implementations, wherein drying the wet fiber web includes ventilating and drying the wet fiber web.

[0109] Eleventh Example Implementation: The method according to any one of the Sixth to Tenth Example Implementations, wherein the compressed dried fiber web is wrinkle-free.

[0110] Twelfth Example Implementation: The method according to any one of the sixth to eleventh example implementations, wherein calendering the dried fiber web comprises: calendering the dried fiber web downstream of a dryer and upstream of a spool of the compressed dried fiber web on a continuous production line for a roll of the compressed dried fiber web; or calendering the dried fiber web on a folder of a roll of the dried fiber web.

[0111] Thirteenth Example Implementation: A stack of packaged tissue paper products formed according to any one of the methods in the Sixth Example Implementation to the Twelfth Example Implementation.

[0112] Fourteenth Example Implementation: A packaged tissue paper product stack, the packaged tissue paper product stack comprising: a plurality of tissue paper products stacked together; and a package surrounding the plurality of tissue paper products, wherein the packaging density of the plurality of tissue paper products and the package is not less than 0.15 g / cm³ and not more than 0.90 g / cm³, and wherein the tissue paper products of the plurality of tissue paper products have an absorption capacity of not less than 3 g water / g tissue paper and not more than 10 g water / g tissue paper.

[0113] Example 15: A stack of packaged tissue paper products according to Example 14, wherein the packaging density of the plurality of tissue paper products is less than 0.20 g / cm³.

[0114] Sixteenth Example Implementation: A stack of packaged tissue paper products according to the Fourteenth Example Implementation or the Fifteenth Example Implementation, wherein the basis weight of the plurality of tissue paper products is not less than 10 g / cm² and not more than 50 g / m².

[0115] Seventeenth Example Implementation: A stack of packaged tissue paper products according to any one of the fourteenth to sixteenth example implementations, wherein the plurality of tissue paper products includes not less than two hundred and fifty tissue paper products and not more than one thousand tissue paper products.

[0116] Eighteenth Example Implementation: A method for forming a tissue paper product, substantially as described herein.

[0117] Example implementation: A stack of packaged tissue paper products, essentially as described herein.

Claims

1. A method for forming tissue tissue product, the method comprising: forming a tissue tissue web using a non-crimp through-air dried continuous process; calendering the tissue tissue web to compress the tissue tissue web; forming a tissue tissue product stack from the tissue tissue web after calendering the tissue tissue web; and packaging the tissue tissue product stack to form a packaged tissue tissue product stack, wherein the packaged tissue tissue product stack has a package density of not less than zero point one five grams per cubic centimeter and not greater than zero point nine zero grams per cubic centimeter.

2. The method of claim 1, wherein the packaged tissue tissue product stack has a package density of less than zero point two zero grams per cubic centimeter.

3. The method of claim 1, wherein the tissue tissue web has a basis weight of not less than one gram per square meter and not greater than five grams per square meter.

4. The method of claim 1, wherein the tissue tissue product of the packaged tissue tissue product stack has an absorbent capacity of not less than three grams of water per gram of tissue tissue and not greater than ten grams of water per gram of tissue tissue.

5. A packaged tissue tissue product stack formed according to the method of claim 1.

6. A method for forming tissue tissue product, the method comprising: depositing fibers onto a forming surface to form a wet web; drying the wet web to form a dry web; calendering the dry web to form a compressed dry web; forming a tissue tissue product stack from the compressed dry web; and packaging the tissue tissue product stack to form a packaged tissue tissue product stack, wherein the packaged tissue tissue product stack has a package density of not less than zero point one five grams per cubic centimeter and not greater than zero point nine zero grams per cubic centimeter.

7. The method of claim 6, wherein the packaged tissue tissue product stack has a package density of less than zero point two zero grams per cubic centimeter.

8. The method of claim 6, wherein the compressed dry web has a basis weight of not less than one gram per square meter and not greater than five grams per square meter.

9. The method of claim 6, wherein the tissue tissue product of the packaged tissue tissue product stack has an absorbent capacity of not less than three grams of water per gram of tissue tissue and not greater than ten grams of water per gram of tissue tissue.

10. The method of claim 6, wherein drying the wet web comprises through-air drying the wet web.

11. The method of claim 10, wherein the compressed dry web is non-crimp.

12. The method of claim 6, wherein calendering the dry web comprises: calendering the dry web on a continuous production line for a roll of the compressed dry web downstream of a dryer and upstream of a spool for the roll of the compressed dry web; or calendering the dry web on a folder for a roll of the dry web.

13. A packaged tissue tissue product stack formed according to the method of claim 6.

14. A packaged tissue tissue product stack, the packaged tissue tissue product stack comprising: a plurality of tissue tissue products stacked together; and ​ a package surrounding the plurality of tissue products, wherein the package density of the plurality of tissue products and the package is not less than zero point one five grams per cubic centimeter and not greater than zero point nine zero grams per cubic centimeter, and wherein the tissue products of the plurality of tissue products have an absorbent capacity not less than three grams of water per gram of tissue and not greater than ten grams of water per gram of tissue.

15. The packaged stack of tissue products of claim 14, wherein the package density of the plurality of tissue products is less than zero point two zero grams per cubic centimeter.

16. The packaged stack of tissue products of claim 14, wherein the basis weight of the plurality of tissue products is not less than ten grams per square meter and not greater than fifty grams per square meter.

17. The packaged stack of tissue products of claim 14, wherein the plurality of tissue products comprises not less than two hundred fifty tissue products and not more than one thousand tissue products.

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