COMPRESSED HOLLOW CORELESS RE-FORMABLE ROLL PRODUCTS

Abstract

A compressed coreless rolled product is described, including an inner surface defining a central cavity having an inner diameter and an outer surface having an outer diameter larger than the inner diameter. The outer diameter is at least five inches and a ratio of the inner diameter to the outer diameter is at least 0.35. Also described is a compressed coreless rolled product with similar inner and outer surfaces, wherein: a difference between the outer diameter and the inner diameter defining a thickness of at least 2.9 inches; and a ratio of the inner diameter to the outer diameter is at least 0.35. An associated method of producing the product is also described, including steps of: winding an absorbent sheet around a forming core member; removing the forming core member to form a coreless rolled product with a diameter ratio of at least 0.35; and compressing the product.

Claims

1. A compressed coreless rolled product comprising: an inner surface defining a central cavity having an inner diameter; and an outer surface having an outer diameter larger than the inner diameter, wherein: the outer diameter is at least five inches; and a ratio of the inner diameter to the outer diameter is at least 0.35.

2. The product of claim 1, wherein the inner diameter is at least 1.75 inches.

3. The product of claim 1, wherein the inner diameter ranges from 1.75 to 4.0 inches.

4. The product of claim 1, wherein the inner diameter is at least 2.0 inches.

5. The product of claim 1, wherein the inner diameter is 2.0 inches and the outer diameter is 5.0 inches.

6. The product of claim 1, wherein the inner diameter is between 2.0 and 3.0 inches.

7. The product of claim 6, wherein the inner diameter is 2.50 inches.

8. The product of claim 1, wherein the outer diameter is 5.6 inches and the ratio is 0.36.

9. The product of claim 1, wherein the outer diameter is 7.0 inches and the ratio is 0.40.

10. The product of claim 1, wherein the outer diameter is between 7.0 and 12.0 inches.

11. A compressed coreless rolled product comprising: an inner surface defining a central cavity having an inner diameter; and an outer surface having an outer diameter larger than the inner diameter, wherein: a difference between the outer diameter and the inner diameter defining a thickness of at least 2.9 inches; and a ratio of the inner diameter to the outer diameter is at least 0.35.

12. The product of claim 11, wherein the thickness is at least 4.0 inches.

13. The product of claim 11, wherein the thickness is between 3.0 and 12.0 inches.

14. The product of claim 11, wherein the thickness is 5.0 inches.

15. The product of claim 11, wherein the thickness is 3.25 inches.

16. The product of claim 11, wherein the ratio is at least 0.40.

17. A method of producing a compressed coreless rolled product, the method comprising the steps of: winding an absorbent sheet around a forming core member until a rolled product having an outer diameter of at least five inches is formed; removing the forming core member from the rolled product to form a coreless rolled product having a hollow central cavity with an inner diameter, a ratio of the inner diameter to the outer diameter being at least 0.35; and compressing the coreless rolled product such that the hollow central cavity is substantially collapsed.

18. The method of claim 17, wherein the forming core member is a tubular paperboard core.

19. The method of claim 18, wherein the tubular paperboard core is re-usable.

20. The method of claim 17, wherein a difference between the outer diameter and the inner diameter defines a thickness, the thickness being 3.0 and 12.0 inches.

21-25. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The invention is described in detail below with reference to the drawings wherein like numerals designate similar parts.

[0014] FIG. 1 illustrates a compressed coreless rolled product in an uncompressed state according to various embodiments.

[0015] FIG. 2A illustrates the compressed coreless rolled product in a compressed state according to various embodiments.

[0016] FIG. 2B illustrates the compressed coreless rolled product in a re-formed state according to various embodiments.

[0017] FIG. 3 illustrates exemplary packaging of the compressed coreless rolled product in the compressed state of FIG. 2A, according to various embodiments.

[0018] FIGS. 4A-4C illustrate various structural and dimensional characteristics of the compressed coreless rolled product according to various embodiments.

[0019] FIG. 5 illustrates the compressed coreless rolled product in the re-formed state of FIG. 2B, further experiencing telescoping according to various embodiments.

[0020] FIG. 6 illustrates a set of exemplary spindles for re-forming and using the compressed coreless rolled product according to various embodiments.

[0021] FIG. 7 is a chart mapping telescoping to a ratio of spindle to central cavity diameter according to various embodiments.

[0022] FIG. 8 is a chart mapping locking up to a ratio of spindle to central cavity diameter according to various embodiments.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

[0023] The invention is described in detail below in connection with the various figures and for purposes of illustration. The invention is also defined in the appended claims. It should be understood, though, that only some, but not all embodiments are shown and described herein. Indeed, the embodiments may take many different forms, and accordingly this disclosure should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Still further, terminology used throughout herein is given its ordinary meaning, except as supplemented immediately below, and like numbers refer to like elements throughout.

[0024] “Tissue” rolls or similar terminology refers to cellulosic fiber tissue products, while “bath tissue” rolls must be flushable and are typically manufactured without a substantial amount of permanent wet strength resin; as opposed to paper toweling, or kitchen roll towel, which has a substantial amount of wet strength resin. Accordingly, the invention described herein may be employed with respect to absorbent papers in which the sheets are not spoiled or defaced, including with bath tissue, kitchen roll towel, other paper toweling formats, or even napkin stock.

[0025] Referring first to FIGS. 1-3 in combination, the compressed coreless rolled product 10 according to various embodiments is illustrated in multiple states, namely an original uncompressed state (see FIG. 1), a compressed state (see FIG. 2A), and a re-formed state (see FIG. 2B). The compressed coreless rolled product 10 may be initially formed by winding the sheet of the compressed coreless rolled product 10 around a forming core member (e.g., a paperboard core) having a diameter ranging from 25 mm to 50 mm. After rolling, the forming core member is removed, providing a hollow coreless roll of the rolled product having a coreless central cavity 12 (see FIG. 2A). The compressed coreless rolled product 10 may then be compressed, into a state as illustrated in FIG. 2A.

[0026] As evident from FIG. 2A, the compressed coreless rolled product 10 maintains a flattened shape having: a substantially collapsed central cavity 12, a pair of longer sides 14 that may be relatively flattened and may have a central portion approaching being generally planar, a pair of shorter sides 16 that after initial compression are more rounded and may approach being generally semi-cylindrical. The compressed coreless rolled product 10 is thus characterized largely by a thickness that is measured from the perpendicularly longer sides 14 through the central axis 20 of the substantially collapsed central cavity 12, which corresponds to the central axis of the forming core member about which the compressed coreless rolled product was initially wound.

[0027] FIG. 2B illustrates the compressed coreless rolled product 10 in the re-formed state. Re-forming may occur by simple application of hand pressure, as described elsewhere herein, principally on the shorter sides 16 of the rolled product. As evident, the compressed coreless rolled product 10 recovers a shape near that of its original state (see FIG. 1), but for certain irregularities expected adjacent the coreless central cavity 12. If desired, the irregularly shaped cavity 12a (see FIG. 2B) may be further re-shaped by hand prior to mounting thereof on a spindle (or the like) for dispensing or on a re-usable dispensing core, which may also be re-inserted prior to mounting the roll on the spindle.

[0028] Although not a focus of the present disclosure, from FIG. 3 it may be understood that a package 50 may be formed containing four (or any desired number of) compressed coreless rolled products 10. Due to the collapsed central cavities 12 and the compressed state of the rolled product (as previously described herein), the size and density of the package 50 may also be compressed. In this example configuration, a volume savings of up to 42% may be achieved as compared to conventional packaging for uncompressed rolled products. Other packaging configurations (not shown) may achieve even larger volume savings, as known. To ensure achievement of maximum savings, a polymer film 52 or comparable wrapping material may be placed around the compressed coreless rolled products 10, thereby ensuring the packaging volume is consistent and constant.

[0029] Turning now to FIGS. 4A-C, illustrated therein are various structural and dimensional characteristics of the compressed coreless rolled product 10 according to various embodiments. Generally, the compressed coreless rolled product 10 has a coreless central cavity 12 (as previously discussed), an interior facing surface 22, and an exterior facing surface 24. Relative to the coreless central cavity 12, the interior facing surface 22 defines an inner diameter 32 (see FIG. 4B) and the exterior facing surface 24 defines an outer diameter 30 (see FIG. 4A) of the compressed coreless rolled product 10.

[0030] Collectively a difference between the outer and inner diameters 30, 32 define a thickness 34 of the compressed coreless rolled product 10. In certain embodiments, the thickness may range from approximately 2.5 inches to 8.0 inches. In at least one embodiment, the thickness may be 2.9 inches. In another embodiment, the thickness may be 7.8 inches. Combinations of these ranges may also be selected for the thickness 34.

[0031] According to various embodiments, the inner diameter 32 may range from approximately 0.5 inches to 6.0 inches. In at least one embodiment, the inner diameter 32 may range from approximately 1.5 to 2.0 inches. In another embodiment, the inner diameter 32 may be any of 1.625 inches, 1.75 inches, 1.83 inches, or 2.25 inches. Combinations of these ranges may also be selected for the inner diameter 32.

[0032] The outer diameter 30 may also vary across a range, dependent in part upon how much volume of material (i.e., paper) is desired for providing on rolled product. This volume may be quantified and/or calculated also based upon the thickness 34 of the product, representing a difference between the outer and inner diameters 30, 32. According to various embodiments, the outer diameter 30 may range from approximately 4.5 to 12.0 inches. In at least one embodiment, the outer diameter may range from 5.0 to 9.0 inches. In another embodiment, the outer diameter 30 is one of at least 5.0 inches, at least 6.0 inches, or at least 7.5 inches. Combinations of these ranges may also be selected for the outer diameter 30.

[0033] The difference between the outer and inner diameters 30, 32 is oftentimes expressed as a ratio (i.e., the inner diameter divided by the outer diameter, referred to elsewhere herein as the “I/O ratio”). According to various embodiments, the I/O ratio may range from 0.03 to 0.95. In at least one embodiment, the I/O ratio ranges from approximately 0.35 to 0.95. In another embodiment, the I/O ratio is at least 0.35. Combinations of these ranges may also be selected for the I/O ratio.

[0034] As a non-limiting example, consider a compressed coreless rolled product 10 having an outer diameter 30 of 5.0 inches and an inner diameter 32 of 1.75 inches. This exemplary product would have an I/O ratio of exactly 0.35. As another example, a compressed coreless rolled product 10 could have an outer diameter 30 of 6.0 inches and an inner diameter 32 of 2.0 inches, also resulting in an I/O ratio of 0.35. Yet another example with an I/O ratio of 0.45 could be achieved with a 5.0-inch outer diameter 30 and a 2.0-inch inner diameter 32. Various combinations can thus be envisioned, all within the scope of the present invention, noting that a minimal inner diameter of 1.75 inches is required to achieve an I/O ratio of 0.35 or higher with a 5.0-inch outer diameter. Still further, as the inner and outer diameters approach one another (i.e., become closer in values), the I/O ratio increases.

[0035] From a theoretical perspective, it is known that hoop stress is imposed upon compressed coreless rolled products like that of the present invention when re-forming of those products is attempted. This may be understood with reference to FIG. 4C, wherein an induced external stress 36 may be imposed upon the previously compressed coreless rolled product 10. The induced external stress 36, in turn, imposes a tangential hoop stress 38 (denoted also as σ in FIG. 4C) upon the compressed coreless rolled product 10. The direction of the imposed tangential hoop stress 38 is denoted by the accompanying arrow in FIG. 4C, notably substantially perpendicular or transverse to the direction of the force applied by the induced external stress 36.

[0036] The equation reproduced below calculates the imposed tangential hoop stress 38.

[00001]${\sigma }_r=\frac{r_i^2{P}_i}{r_o^2-r_i^2}\left(1-\frac{r_i^2}{r_o^2}\right)$

[0037] The tangential hoop stress 38 (denoted also as σ) based upon the outer diameter 30 dimension (denoted as ½ thereof in terms of a radius r.sub.o), the inner diameter 32 dimension (denoted as ½ thereof in terms of a radius r.sub.i), and the induced external stress 36 (denoted as P).

[0038] Notably, induced tangential hoop stress 38 governs, at least in part, how easily a compressed coreless rolled product 10 can be reformed. Specifically, the tangential hoop stress 38 is heightened as the difference between the inner diameter 32 and the outer diameter 30 decreases. Stated another way, the tangential hoop stress 38 is heightened as the I/O ratio increases. Thus, with an I/O ratio of at least 0.35, as provided in certain embodiments, a tangential hoop stress 38 is induced that is greater than that induced is the I/O ratio were, for example, 0.15.

[0039] As a result of the heightened tangential hoop stress 38 with a greater I/O ratio, re-forming of the compressed coreless rolled product 10 requires less externally induced stress 36. Stated otherwise, it is easier for consumers (or others) to re-form the compressed coreless rolled product according to various embodiments, as compared to conventional rolled products having a lower I/O ratio. As a non-limiting example, if a compressed coreless rolled product 10 according to the present invention comprises an outer diameter of about 5.6 inches and an I/O ratio of about 0.36, the tangential hoop stress induced increases by about 52%, as compared to conventional rolled products.

[0040] Notably, having an increased I/O ratio according to various embodiments (whether greater than 0.35 or otherwise), requires a certain degree of increase in the inner diameter 32 of the compressed coreless rolled product. For example, as compared to certain conventional rolled products having an inner diameter of 1.6 inches and an outer diameter of 4.75 inches, the I/O ratio is less than 0.35. Similarly, it is not possible to achieve an I/O ratio of greater than 0.35 with an outer diameter less than 5.0 inches without having an inner diameter that is larger than conventional inner diameters. An additional advantage due to this arises regarding telescoping.

[0041] Referencing now FIG. 5, illustrated therein is an occurrence of telescoping in a compressed coreless rolled product 10. As generally known and understood, telescoping is a defect in a rolled product attributable, at least in part, to a poorly re-formed and unclear central cavity 12, which can lead to obstruction of proper loading of the rolled product onto a dispenser, such as a spindle (see FIG. 6). As illustrated in FIG. 5, an inner portion 42 of the rolled product is axially extended (i.e., telescoped) outwardly relative to the winding of the material of the remainder (or outer) portion 40 of the rolled product. Telescoping can result in unused portions of the rolled product, typically with respect to the inner portion 42 that exhibits the telescoping.

[0042] Another recognized advantage from various embodiments is that, as the inner diameter increases (for purposes of increasing the I/O ratio, as previously described herein) a difference between the inner diameter and a diameter of an associated spindle, as may be used to mount the compressed coreless rolled product 10 is also potentially increased, dependent in part upon the diameter of the spindle itself. FIG. 6, in this regard, illustrates an exemplary spindle 100. As generally known, a spindle 100 may include opposing end portions 104 (i.e., stoppers to retain the rolled product once mounted) and an intermediate rod 102 that is spindle-like or elongated in shape and extending between the opposing end portions. Certain spindles, as illustrated, may provide a nesting configuration for the rod 102, with separate outer 102a and inner 102b portions being provided, each having slighting differing (outer>inner) diameters 104a, 104b. Various spindle rod 102 diameters are well-known and understood, with the limitation that they are dimensionally less than the inner diameter dimensions of central cavities of associated rolled products.

[0043] As mentioned, though, as the inner diameter increases (to increase the I/O ratio), a ratio of spindle to inner (or central cavity) diameter increases. As this spindle/cavity ratio increases from 1 to 3, occurrences of telescoping are reduced. This is evident not only from chart 200 of FIG. 7, but also from the data presented in Table 1, immediately below.

TABLE-US-00001 TABLE 1 Percent Differences Between Central Cavity Diameters Telescoping Ratio 1.625″ 2.0″ % Difference    1-1.25 20.83% 12.50% 66.67% 1.25-1.5  20.00% 14.29% 40.00%  1.5-1.75 12.50% 11.11% 12.50% 2-3  0.00%  0.00%  0.00% 3 & up  0.00%  0.00%  0.00%

[0044] As illustrated above, it is also evident that a compressed coreless rolled product 10 according to various embodiments, having an inner diameter of 2.0 inches exhibits less telescoping (or a lowered risk thereof), as compared to conventional rolled products having an inner diameter of 1.625 inches. Above and beyond a spindle/central cavity ratio of 2-3, telescoping is virtually eliminated. And although this is true regardless of the inner diameter of the rolled product, occurrences are significantly lower with a larger inner diameter product (i.e., one also having a heightened I/O ratio, as previously described). For example, a 23% inner diameter increase to 2.0 inches reduces telescoping issues up to 67%, as compared to a conventional 1.625-inch cavity diameter.

[0045] Referencing now FIG. 8, illustrated therein is a chart 300 mapping a relationship between spindle/central cavity ratio and the “locking-up” phenomena. While locking up occurrences start higher for the 2.0 inch inner diameter compressed coreless rolled products 10, it is consistently lower from a ratio of 1 and upward, revealing additional advantages with coupling of high spindle/central cavity and I/O ratios, at least with respect to re-forming, telescoping, and locking up. Further data regarding locking-up advantages observed are provided in Table 2, below. For example, it may be seen that a 23% inner diameter increase to 2.0 inches reduces telescoping issues up to 150%, as compared to a conventional 1.625-inch cavity diameter.

TABLE-US-00002 TABLE 2 Percent Differences Between Central Cavity Diameters Locking up Ratio 1.625″ 2.0″ % Difference up to 1 63.64% 100.00%  −36.36%   1-1.5 47.73%  27.78%  71.82% 1.5-2 56.25%  27.78% 102.50% 2-3 33.33%  33.33%   0.00% 3 & up 50.00%  20.00% 150.00%

[0046] Further data regarding reductions in telescoping and locking-up observed in various studies conducted is shown in Tables 3-6, provided below. The methodology employed in these studies, conducted to demonstrate certain non-limiting advantages achieved by one or more (or a combination of) increased I/O ratio, increased spindle to inner diameter (or central cavity diameter) ratio, and increased outer diameter, involved testing a hypothesis that properly finding the center of the compressed coreless rolled product is influential to alleviating telescoping and locking-up issues. For example, participants who indicated telescoping and locking-up issues were provided an additional compressed coreless rolled product to test. Those participants then exhibited a 45% decrease in telescoping and a 61% decrease in locking-up once the center of the compressed coreless rolled product 10 was properly located. Further, it was shown that an increased inner diameter improved participants' ability to reform and install the compressed coreless rolled product 10. It should be appreciated, though, that the studies conducted, including their results, are non-limiting examples and supportive of the further detailed disclosure provided elsewhere herein.

[0047] As can be seen in Tables 3-4 below, a first study involving a compressed coreless rolled product 10 having a 1.6″ inner diameter and a second studying involving a compressed coreless rolled product having a 2.0″ inner diameter was conducted. As observed, the increased inner core diameter engendered an increased consumer acceptance of the format. Stated another way, participants in the two studies felt they gained more benefits (i.e., reduced telescoping and locking-up) while using the 2.0″ inner diameter compressed coreless rolled product, and were willing to change their own behavior (e.g., more carefully find the center of the compressed coreless rolled product) to enjoy those benefits.

TABLE-US-00003 TABLE 3 Telescoping & Locking Data Studies 1 & 2 1.6″ core 2.0″ core % Change Telescoping (%) Yes 11 7 −36 No 89 93 4 Not Roiling (%) Very Often/Sometimes 25 14 −44 Seldom/Never 75 86 15 Got To Last Sheet (%) Yes 75 79 5 No 25 21 −16

TABLE-US-00004 TABLE 4 Benefits & Try/Purchase Data from Studies 1 & 2 1.6″ Core 2.0″ core % Change Benefits (%) Yes 82 84   2% No 18 16  −11%   Benefits Change Behavior (%) Yes 21 48 129% No 79 52  −34%   Issues Prevent Purchase (%) Yes 48 20  −58%   No 52 80  54% Try Use Again (%) Yes 84 93  11% No 18 7  −61%  

[0048] Observed in Table 5 below is data related to participants included in both the first study and the second study. As shown, 60% of participants successfully resolved their issues when given a second compressed coreless rolled product to try. Those participants who continued to experience difficulty were given a third compressed coreless rolled product. A comparison of this third study to the second study is observed in Table 6 still further below.

TABLE-US-00005 TABLE 5 Participant Ratings that were a Part of Both Studies 2.0″ core Second Test (%) Yes 62 No 38 Issues Solved 2nd Time (%) Yes 60 No 40 Rate Between Tests (%) First Better 3 Second Better 33 Same 55 Neither 9

[0049] Table 6 below, shows that instances of telescoping continued to decrease when participants were given a third compressed coreless rolled product and successfully found the central cavity thereof. Moreover, fewer participants complained of sheets falling off at the end of the roll or improperly dispensing. Accordingly, the number of participants that perceived benefits, would change behavior for said benefits and try/purchase again increased.

TABLE-US-00006 TABLE 6 Results between Study 2 & Study 3 2.0″ core 2.0″ core & Spindle % Change Telescoping (%) Yes 7 6 −14% No 93 94    1% Not Rolling (%) Very Often/Sometimes 14 10 −31% Seldom/Never 86 90    5% Got To Last Sheet (%) Yes 77 85   10% No 23 15 −35%

CONCLUSION

[0050] Many modifications and other embodiments will come to mind to one skilled in the art to which this disclosure pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the disclosure is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.