Tampon applicator with improved insertion tip
11304857 · 2022-04-19
Assignee
Inventors
Cpc classification
International classification
Abstract
An insertion end for a tampon applicator assembly. The insertion end has an insertion tip region and optionally an inflection region. The insertion end of the tampon applicator assembly is unique in one or more ways, including one or more of the following: having a unique degree of closure, an inflection region length that is different than an insertion end region length, petal slits that form a tear-drop shape, petals having multiple radii of curvature, the insertion end having a unique radius of curvature, the insertion end having a unique part thickness.
Claims
1. A tampon assembly, comprising: a tampon applicator having an insertion end adjacent a barrel region, the insertion end having between three and eight petals that are separated by slits, the petals having a free end defining a forward most end of the insertion end, the insertion end having a rearward most end defined by termination of the slits, the insertion end having a radius of curvature generally defining an exterior geometry of the insertion end between the forward most end and the rearward most end exceeding about 0.400 inches, wherein the slits are arcuately shaped, wherein the termination of the slits form a tear-drop shape having a radius of curvature between about 0.028 inches and about 0.030 inches, wherein each of the petals has a formed petal length of between about 0.40 inches and about 0.48 inches, wherein a total slit length between each of the petals is between about 0.50 inches and about 0.58 inches; and a tampon pledget contained within the barrel region of the tampon applicator; wherein an ejection force that is required to eject the tampon pledget out of the barrel region through the insertion end is between 9.8 ounces and about 13.8 ounces.
2. The insertion end according to claim 1, wherein the each of the petals has a petal width between about 0.24 and 0.42 inches.
3. The insertion end according to claim 2, wherein the free end of each petal define an inscribed polygon, the inscribed polygon defines an inscribed circle with a diameter of between about 0.075 inches and about 0.150 inches.
4. The insertion end according to claim 3, wherein a degree of closure between the inscribed circle and the termination of the slits of the petals is between about 0.1 and about 0.3.
5. The insertion end according to claim 1, wherein each of the petals have a petal length that is the same.
6. The insertion end according to claim 1, wherein each of the slits are equal in length.
7. The insertion end according to claim 1, wherein each of the petals are substantially uniform.
8. The insertion end according to claim 7, wherein each of the petals are substantially uniform and each petal has a high degree of uniformity.
9. The insertion end according to claim 8, wherein each of the petals has an area, wherein each petal has a thickness that does not vary by more than about 25% across the petal area.
10. The insertion end according to claim 9, wherein the thickness of the petal does not vary by more than about 10% across the petal area.
11. The insertion end according to claim 9, wherein the thickness of the petal does not vary by more than about 2% across the petal area.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
DETAILED DESCRIPTION
(21) The tampon applicator assembly 10 of the present disclosure has many general features in common with tampon applicators known in the art, i.e., a plunger 16 and a barrel 14 being generally tubular in shape defining a hollow cavity 15 and having two opposing ends 44, 84—a forward most end 44 and a rearward most end 84—wherein each end 44, 84 comprises an opening. The barrel 14 includes one or more of an insertion end 26, a main body region 36, and a reverse taper region 38, a grip region 40. The main body region 36 has a length 72, the finger grip region 40 has a length 74, and the reverse taper region 38 has a length 76. The tampon applicator 12 has a plunger 16 slideably disposed in the hollow cavity 15 and the rearward most end 84. The forward most end 44 has an insertion end 26. The insertion end 26 includes a plurality of petals 45. The petals 45 are initially in an unformed or straight position, and after assembly of the tampon applicator assembly 10 is sufficiently completed (i.e. at least the tampon pledget 22 is inside the hollow cavity 15, as shown at least in
(22) The tampon applicator 12 is a full-sized applicator 12 having a full-size barrel 14 and optionally a single piece plunger 16 as shown in
(23) For example,
(24) To improve insertion ease of the applicator 12, the architecture of the insertion end 26 has been reconfigured. Prior to operation of the applicator 12 but after assembly of the tampon applicator assembly components, the insertion end 26 has a defined taper, length, and closure. Such characteristics are determined by the shape and length of the individual petals 45 and/or the inflection curvature 54. Differences between the tampon applicator 12 of the present disclosure and the prior art can include one or more of the introduction of a unique or larger degree of closure at the forward most end 44 of the insertion end 26, lengthening of the petals 45 that form the insertion end 26 or lengthening the inflection curvature 54, having a unique petal gap 51, and/or the use of differently shaped petals 45 (i.e. curvature, width, thickness). As for the latter, differently shaped petals include petals 45 having different or multiple radii of curvature, having different shaped slits 48, having slits 48 with distinct radii of curvature. In such embodiments, the shape of the petals 45 leads to a unique inflection curvature 54, and/or an insertion end 26 having multiple radii of curvature.
(25) The insertion end 26 includes an insertion tip region 32 and optionally an inflection region 34. The insertion tip region 32 and inflection region 34 are distinct, overlap, or coincide. In any embodiment, the insertion tip region 32 defines the length 62 of the formed petals 45 (i.e. the length of the free end 46 of the petal 45 to the base where the slits 48 separating the petals 45 terminate 50). While the inflection region 34 defines the length 66 (i.e. the inflection region length 66) that corresponds to the inflection curvature 54 of the insertion end 26. The applicator 12 has between 3 and 8 petals 45 that define the insertion end 26.
(26) The insertion end 26 via the petals 45 defines a closure geometry, or said differently, defines the amount of space between the free petal ends 46. The closure geometry is defined by the inscribed shape 56 amongst the free petal ends 46 (i.e. petal tips), which is typically a polygonal shape. For instance, if the insertion end 26 has four petals 45, the inscribed polygon 56 might resemble a quadrilateral. The closure geometry (defining a polygon) further defines a circle 58 inscribed within the polygon 56. The diameter 60 of the circle 58 is between about 0.075 inches and about 0.150 inches.
(27)
(28) The tampon applicator 12 of the present disclosure may contain a barrel 14 that comprises either a linear or tapered main body region 36, and typically comprises a textured 42 finger grip region 40, although some embodiments may lack a well-defined textured 42 finger grip region 40. The textured 42 finger grip region 40 include ribs, embossing, slits, and/or other three-dimensional topographies.
(29) The tampon applicator 12 of the present disclosure has a tapered insertion end 26 defined in part by a taper ratio. The taper ratio is defined by the boundary of the insertion end 26. That is, where the inflection region 34 extends beyond the insertion tip region 32, the “boundary” is defined by the length, diameter and radius of the inflection curve 54 (i.e. the length 62 of the insertion tip region 32 and any additional length 66 provided by the inflection region 34, and the diameter 86 and radius 82 of the inflection region). Alternatively, where the inflection region 34 overlaps the insertion tip region 32, the “boundary” is defined by the length, diameter and radius of the insertion tip region 32 (i.e., the length 62 of the insertion tip region 32, and the diameter 78 and radius 80 of the insertion tip region 32). As such, the taper ratio of the insertion tip region 32 is defined by the ratio of the length of the taper projection along a longitudinal axis 11 of the barrel 14 (i.e. the formed length 62 of the insertion tip region 32) to the length of the taper projection along a radius 80 of the barrel 14 at the termination 50 of the plurality of slits 48 of the insertion end. The taper ratio of the insertion end 26 having an insertion tip region 32 and an inflection region 34 is defined by the ratio of the length of the taper projection along the longitudinal axis 11 of the barrel 14 (i.e., the formed length 66 of the inflection curve 54, typically including the formed length 62 of the insertion tip region 32 and the addition or subtraction of the formed length 66 of the inflection region 34). For example,
(30)
(31) The tampon applicator 12 of the present disclosure has a tapered insertion end 26 with a taper ratio of at least 1.0, or 1.2, or typically at least 1.3 and in many cases 1.4, 1.5, 1.6, 1.7 or higher.
(32) In some embodiments, it is advantageous to modify the insertion end 26 such that the insertion end 26 extends beyond the base region 47 of the petals 45 (i.e. beyond the slits 48 between the petals 45). In these embodiments, the insertion end 26 includes a portion extending to the base region 47 of the petals 45 which is an inflection region 34 beyond the insertion tip region 32 and up to the main body region 36. In these embodiments, an inflection curvature 54 extends from the free end 46 of the petals 45 as defined by (or defining) the insertion end 26 and continues to have a portion of the inflection curvature 54 beyond the base region 47 of the petals 45 and up to the main body region 36 in the inflection region 34. This portion between the base region 47 of the petals and the main body region 36 is described as the inflection region 34.
(33) Alternatively, in some embodiments, the inflection region 34 and insertion tip region 32 overlap and/or at least partially coincide. In these embodiments, the inflection curvature ends 54 at an axial length 62 of the petals 45 between the free end 46 of the petals 45 and the base region 47 (i.e. where the slits 48 between the petals 45 terminate 50). In these embodiments, the inflection region 34 is the portion of the length 66 between the end of the inflection curvature 54 and the termination 50 of the slits 48 separating the petals 45.
(34)
(35)
(36)
(37)
(38) In some embodiments, in view of the additional length 66 of the insertion end 26 due to the inflection region 34 increasing the inflection curvature 54 beyond the base region 47 of the petals 45, where the axial length 66 of the inflection region 34 does not exceed the diameter 86 where the inflection curvature 54 terminates, a correlation can be drawn between (a) the axial length 62 of the insertion tip region 32, (b) the axial length 66 of the inflection region 34, and (c) the hypotenuse 88 of the inflection curve 54 can also be thought of by the following equation:
hypotenuse 88 of the inflection curve 54>√((axial length of the insertion tip region).sup.2+(axial length 62 of the insertion tip region 32+axial length 66 of the inflection region 34).sup.2)
(39) For clarity, above equation is not a usage of the Pythagorean theorem, as it does not reflect three sides of a right triangle. Rather, it demonstrates that in certain embodiments, the square of the hypotenuse 88 of the inflection curve 54 is greater than the sum of the squares of the aforementioned axial lengths 62, 66. In other words, the insertion end 26 is lengthened 62 via the inflection region 34 by a distance less than the diameter 86 of the barrel 14 where the inflection curve 54 terminates and thus what normally might be hypotenuse 90 for the insertion tip region 32 (i.e. the hypotenuse 90 from the free petal ends 46 to the termination 50 of the slits 48 between the petals 45). This concept can be utilized in both formed and unformed states, as it relates to external geometry and also to internal geometry 14a as discussed below. For instance, diameter 86 is referred to as diameter 86a in the context of external geometry and diameter 86b in the context of internal geometry 14a, and likewise, hypotenuse 88 and 90 are 88a and 88b and 90a and 90b for external “a” and internal geometries “b”. Also likewise, the insertion tip region 32 lengths 62 and 64, in the formed and unformed states, respectively, would be 62a and 64a, respectively, as it relates to external geometry 14b, and 62b and 64b, respectively, as it relates to internal geometry 14a. Additionally, the inflection region 34 lengths 66 and 68, in the formed and unformed states, respectively, would be 66a and 68a in the formed and unformed states, respectively, as it relates to external geometry 14b, and would be 66b and 68b in the formed and unformed states, respectively, as it relates to internal geometry 14a. Further, while the inflection curvature 54 is determined when in the formed state, inflection curvature 54 also has an unformed length 68 that can be determined by geometric calculations of the insertion end 26 in the formed state. Likewise, the insertion tip region 32 has an unformed length 64.
(40) Internal geometry 14a relates to, inter alia, ejection efficiency. Internal geometry 14a focuses on a correlation of the internal radius 80a of the barrel 14 where the slits 48 between the petals 45 terminate 50, and internal radius 82a describes the internal radius at the inflection region 34; internal geometry correlates how either or internal radii 80b and 82b compare to the length 62 of the formed petal 45. A longer or more gradual taper that is more conducive towards ejection efficiency would be achieved to the extent the length 62 between the free ends 46 of the petals 45 (when formed) length 66 of the inflection region 34 (when formed) is greater than the radius of interior surface 82b surface 82a where the inflection region 34 ends and the main body region 36 begins. In some embodiments, the length between the interior surface of the free ends 46b of the termination 50 of slits 48 of the petals 45 is greater than the interior radius 80b of the barrel 14 where the insertion tip region 32 meets the main body region 36. In some embodiments, the length between the interior of the free petal ends 46b and where the inflection region 34 meets the main body region 36 is greater than the interior radius 82b where the inflection region 34 meets the main body region 36.
(41) The internal hypotenuse 88b and/or 90b is particularly useful in that also describes how well the pledget 22 nests within the insertion end region 26, which contributes to improved insertion ease. A pledget 22 shaped such that at least a portion of the pledget 22 intersects the internal hypotenuse 88b and/or 90b indicates the pledget 22 supports at least a portion of the insertion tip end 26. In some embodiments, the pledget 22 intersects the insertion tip region 26 hypotenuse 88 and/or 90. In some embodiments, the pledget 26 intersects the inflection curve hypotenuse 90. In yet other embodiments, the pledget 22 intersects both the insertion tip region 26 hypotenuse 88 and the inflection curve 54 hypotenuse 90. While the internal geometry 14a is preferred, for simplicity, measurements can be made from external geometries 14b as well where the thickness 14c is small. Said differently, applicators 12 are typically thin parts and as such, the pledget will likely intersect any such internal hypotenuse 88b or 90b if pledget 22 intersects external hypotenuse 88a or 90a. Further, the hypotenuse 88 and/or 90 is to be calculated in the formed state. In some embodiments, the pledget 22 supports at least the free ends 46 of the petals 45 as the pledget 22 is ejected. While some embodiments have a pledget 22 shape that is substantially similar to the insertion end region 26, some embodiments do not require such as insertion into the body necessitates bodily forces that press upon the applicator 12 (i.e. at the insertion end region 26) and thus push the insertion end 26 into contact with the pledget 22. As such, to the extent the insertion end region 26 and pledget 22 shape are somewhat similar in at least some of the characteristics described throughout the present disclosure, greater insertion ease or comfort is achieved and improved.
(42) External geometry 14b, as it relates to internal geometry 14a also impacts ejection efficiency. A thinner petal 45 typically deflects under less force than a thicker petal 45, and as such, the relative thickness 14c of the petal 45 can impact ejection efficiency. As it may be difficult to create a very thin petal 45, portions of the petal 45 may be locally thinner than other portions of the petal 45, and provide improved ejection efficiency. These locally thinner regions can provide an aesthetic that indicates to the consumer that the applicator 12 has improved insertion ease (i.e. at least one of ejection efficiency and insertion comfort).
(43) The present disclosure further contemplates elongated petals 45. It has also been found that increasing the length 49 of the petals 45 will also decrease the amount of force required to eject a pledget 22 from the barrel 14 thus improving ejection efficiency. Note that petal length 49 in various embodiments, is the same as either or both of the length 62 (or 64) insertion tip region 32 and the length 66 (or 68) of the inflection region 34. Similarly, and as taught throughout the present disclosure, petal length 49a regards external geometry 14b and petal length 49b corresponds to internal geometry 14a. For example, consider a slit 48 in
(44) Extending the slit 48 as suggested also changes the shape of the petal 45 and the taper ratio. That is, a petal 45 that was largely a semi-circle or parabola now has a portion near the base region 47 that is largely linear. For example,
(45) The present disclosure further contemplates insertion end 26 configurations having varying spacing amongst the petals 45.
(46) The closure diameter (i.e. the insertion end opening 30) and its impact on ejection force is demonstrated in the below Table 1:
(47) TABLE-US-00001 TABLE 1 Closure Diameter vs. Ejection Force Metric Range Δ Closure Diameter 0.075 in 0.150 in 0.075 in Ejection Force 6N 3.5N 2.5N
(48) The above Table 1 demonstrates the ability to modify ejection force by one (1) Newton (3.6 ounces) by changing the closure diameter 30 by 0.76 mm (0.030 inches). In other words, one can increase or decrease ejection force by one (1) Newton by increasing or decreasing, respectively, the closure diameter 30 by 0.76 mm. Another way to describe the relationship of the closure diameter 30 and ejection force is by modifying the closure diameter 30 by 1 mm (0.039 inches), the ejection force is modified by 1.312 Newton (4.719 ounces).
(49) It has been found, as demonstrated above, that enlarging the insertion end 26 opening 30 will decrease the amount of force required to eject a pledget 22 from the barrel 14. This effect is relatively more pronounced in an insertion end 26 with a larger taper, e.g., the insertion end 26 shown the schematic of
(50) The length of the petals 45 also influence ejection force, as demonstrated in the below Table 2:
(51) TABLE-US-00002 CHART 2 Petal Length vs. Ejection Force Metric Range Δ Petal Length 8.5 mm 12.5 mm 4 mm Ejection Force 5.5N 2.5N 3N
(52) The above Table 1 demonstrates the ability to modify ejection force by one (1) Newton (3.6 ounces) by changing the petal 45 length 49 by 1.33 mm (0.052 inches). In other words, one can increase or decrease ejection force by one (1) Newton by increasing or decreasing, respectively, the petal 45 length 49 by 1.33 mm. Another way to describe the relationship of petal 45 length 49 and ejection force is by modifying the petal 45 length 49 by 1 mm (0.039 inches), the ejection force is modified by 0.75 Newton (2.698 ounces).
(53) Petal 45 gap 51 geometry describes the petal slit 48 at the base region 47 of the petals 45 and is also within the scope of the present disclosure. A tear-drop shaped gap 51 improves insertion ease. The radius of curvature 52 of the gap 51 is between about 0.028 inches and about 0.030 inches. The diameter of the gap 51 is between about 0.020 inches and about 0.056 inches. In some embodiments, the gap 51 between adjacent petals 45 is greater than about 0.005 inches.
(54) The insertion end 26 has a radius of curvature 96 between about 0.200 inches and about 0.420 inches. In other embodiments, the insertion end 26 has a radius of curvature 96 exceeding about 0.400 inches, or exceeding about 0.420 inches. In some embodiments, the insertion end 26 has a first radius of curvature 96a between about 0.202 inches and about 0.220 inches. In some embodiments, the insertion end 26 has a second radius of curvature 96b between about 0.336 inches and about 0.409 inches. In some embodiments, the insertion end 26 has a third radius of curvature 96c between about 0.373 inches and about 0.392 inches. In some embodiments, the insertion end 26 has a radius of curvature 96 between about 0.201 inches and about 0.399 inches.
(55) The insertion end 26 of the present disclosure is at least ten percent (10%) of the length 70 of the entire formed applicator barrel 14. In some embodiments, the length 70 is between about 2.0 and about 3.5 inches, and more preferably between about 2.5 and 3.0 inches. In some embodiments, the length is greater than about 2.0 inches, or less than about 3.5 inches. In further embodiments, the length is between about 2.75 inches and 3.0 inches. In some embodiments, the length of the insertion end 26 is at least fifteen percent (15%) of the length 70 of the entire formed applicator barrel 14. In further embodiments, the length of the insertion end 26 is at least twenty percent (20%) of the length 70 of the entire formed applicator barrel 14. Recall the insertion end 26 length is either or both of the length 62 or 64, respectively, of the insertion tip region 32 and/or the length 66 or 68, respectively, of the inflection region 34, depending on the embodiments as discussed throughout the present disclosure.
(56) The length 72 of the main body region is at least 1.25 inches, or up to about 2.0 inches, and more preferably between 1.25 inches and 1.75 inches. The length 74 finger grip region 40 is at least about 0.5 inches, or up to about 1.0 inches, and more preferably between about 0.50 inches and about 0.75 inches. The length 76 of the reverse taper region 38 is at least 0.10 inches, or up to about 0.5 inches, or more preferably between about 0.125 inches and about 0.4 inches.
(57) Applicators 12 of the present disclosure can be modeled similarly to a modified cantilevered beam equation. Such a model, referred to as the applicator deflection modulus, relates the number of petals 22, Young's Modulus, the moment of inertia, deflection, petal 45 length 49, the width 43 of the petal 45, thickness 14c of the petal 45 at its base region 47, the diameter 78 of the barrel 14 at the termination 50 of the slits, and the radius of curvature 52 of the gap 51 between adjacent petals 45 at their base regions 47. The model has been verified against currently known applicators, including the PLAYTEX SPORT applicator and PLAYTEX GENTLE GLIDE APPLICATOR. Inventive samples of the present disclosure have also been modeled. The model provides a basis for modifying certain aspects of the insertion end 26, insertion tip region 32, inflection region 34, and/or petals 45 to promote improved tampon assembly 10 performance.
(58) The aforementioned cantilever beam equation is defined as follows, from both a petal length standpoint and a petal thickness standpoint:
(59) Cantilever Beam Equation—Petal Thickness
Definitions
(60) F.sub.pb=Petal Bending Force
(61) F.sub.e=Ejection Force
(62) N=Number of Petals
(63) E=Young's Elastic Modulus
(64) I=Second Moment of Inertia
(65) L.sub.f=Formed Petal Length
(66) δ=Deflection
(67) b=Width of the Petal at the Base
(68) t=Thickness of the Petal
(69) d.sub.barrel=Outer Diameter of the Barrel at the Petal Base
(70) d.sub.tear=Diameter of the “Tear Drop” in the Petal
(71) Bending force for a single petal:
(72)
(73) Ejection force for multiple petals:
(74)
(75) Converting ejection force to ounces:
(76)
(77) Assuming E has units of psi, and d.sub.barrel, d.sub.tear, t, L.sub.f, and δ have units of inches.
(78) Cantilever Beam Equation—Petal Thickness
Definitions
(79) F.sub.e=Ejection Force
(80) N=Number of Petals
(81) E=Young's Elastic Modulus
(82) I=Second Moment of Inertia
(83) L.sub.f=Formed Petal Length
(84) δ=Deflection
(85) b=Width of the Petal at the Base
(86) t=Thickness of the Petal
(87) d.sub.barrel=Outer Diameter of the Barrel at the Petal Base
(88) d.sub.tear=Diameter of the “Tear Drop” in the Petal
(89) t.sub.e=effective thickness
(90) t.sub.max=Maximum Petal Thickness
(91) t.sub.min=Minimum Petal Thickness
(92) α=Percentage of “Thick” Petal Regions (0<α<1)
(93) β=Percentage of “Thin” Petal Regions (0<β<1)
(94) n=Number of Regions of Thickness “i”
(95) t.sub.i=Thickness “i”
(96) ε.sub.i=Percentage of t.sub.i throughout the Petal
(97) Ejection force for multiple petals:
(98)
(99) Effective thickness expressed as a function of two different thicknesses:
t.sub.e=αt.sub.max+βt.sub.min
(100) Effective thickness expressed as a function of as a series of thicknesses:
t.sub.e=Σ.sub.i=1.sup.n∈.sub.it.sub.i
(101) Ejection force based for a petal with varying thicknesses;
(102)
(103) Ejection force for a petal with varying thicknesses in ounces:
(104)
(105) Assuming E has units of psi, and d.sub.barrel, d.sub.tear, t, L.sub.f, and δ have units of inches.
(106) Many tampon applicators 12 are made from plastic materials, and as such, the Modulus of Rigidity is generally between about 27,000 psi and about 70,000 psi.
(107)
(108) Chart 3 below describes some embodiments using theoretical and actual measurements:
(109) TABLE-US-00003 CHART 3 Theoretical and Actual Ejection Forces Sample Slit Length- Formed Formed Total Gentle Theoretical Actual Actual Petal Petal Gap Slit Slit R1/Total Glide Slit Ejection Ejection Ejection Length Length R1 Radius Length Length Slit Length Force Force Force Sample [mm] [in] [in] [in] [in] [in] Length [in] [oz] [oz] [N] Current 0.576 0.028 0.403 0.431 1.336 0.000 18.866 13.800 GENTLE GLIDE Current 0.955 0.010 0.592 0.602 1.586 0.171 8.451 9.840 SPORT Sample 0 0.955 0.010 0.530 0.540 1.769 0.109 11.839 10.500 Control 8.743 0.344 0.576 0.028 N/A 0.431 1.336 N/A N/A 18.895 5.253 Sample A 10.293 0.405 0.576 0.028 0.501 1.150 13.862 3.854 Sample B 10.704 0.421 0.576 0.028 0.521 1.106 13.507 3.755 Sample C 11.220 0.442 0.576 0.028 0.541 1.065 11.663 3.243 Sample D 11.991 0.472 0.576 0.028 0.561 1.027 10.260 2.852 Sample E 12.394 0.488 0.576 0.028 0.581 0.991 9.800 2.724 Sample F 0.576 0.028 0.592 0.620 0.929 0.189 7.532 N/A N/A Sample G 0.576 0.028 0.530 0.558 1.032 0.127 10.816 Current 0.360 0.018 0.328 0.346 1.040 N/A 25.713 17.190 Radiant
(110) The model is based on a known hemispherical insertion tip such as that of the PLAYTEX GENTLE GLIDE. Due to this basis in the theoretical model, the PLAYTEX GENTLE GLIDE theoretical numbers deviate from actual. Nonetheless, as demonstrated by the above Chart 3, the theoretical model does demonstrate how the petal gap 51 and petal length 49 can impact ejection force. Chart 3 is exemplary and not limiting.
(111) It can also be appreciated that other changes to the shape of the curved portion of the petal 22, e.g., a blunter terminus, difference in the slope along portions of the curve or along the entire curve, can also affect ejection force or insertion comfort. Further, the degree of curl inwards toward the longitudinal axis 11 of the barrel 14 can have an impact on these features.
(112) The tampon applicator 12 of the present disclosure also has specific performance features, for example, from about 5 oz. to about 25 oz. of ejection force is required to eject a pledget 22 from the barrel 14 of the tampon applicator 12, typically less than 25 oz., e.g., 20 oz or less is required, and often 15 oz. or less is required to eject a pledget 22. Thus, in various embodiments, the tampon applicator 12 requires from about 8 to about 20 oz., i.e., 2.2 to 5.6 N, e.g., about 10 to about 20 oz, i.e., 2.8 to 5.8 N, about 10 to about 15 oz., i.e., 2.8 to 4.2 N, or about 10 to about 12 oz., i.e., 2.8 to 3.3 N, to eject the pledget 22.
(113) Embodiments of the present disclosure provide tampon applicators 12 incorporating one or more of these findings. A general embodiment of the present disclosure provides a tampon applicator 12 comprising a plunger 16 and a barrel 14, said barrel 14 being generally tubular in shape and comprising a main body region 36 having a generally circular or elliptical hollow interior cavity 15, a forward most end 44 that defines a tapered insertion end 26 formed by from 3 to 8 petals 45, the insertion end 26 terminates at an opening 30 defined by the free ends 46 of petals 45. The insertion end 26 has a generally circular or elliptical shape that is similar to that of the hollow interior cavity 15 of the main body region 36 where the insertion end 26 adjoins the main body region 36, and a rearward most end 84 opposing the forward most end 44, said rearward most end 84 having an opening 31 in which the plunger 16 is slideably disposed, wherein the insertion end 26 has a taper ratio as defined above of from about 1.3 to about 3.5, and the insertion end 26 opening 30 has a degree of closure as defined above of from about 0.1 to about 0.3, which tampon applicator 12 requires an ejection forces of from about 5 to about 25 oz to eject an absorbent pledget 22.
(114) In most embodiments the barrel 14 has a circular interior, i.e., a cross section of the main body region 36 of the barrel 14 defines an enclosed circle, and the insertion end 26 opening 30 has an inscribed circle 60. It should be understood that the actual shape of the insertion end 26 opening 30 is not that of a simple circle—the shape of the free ends 46 of the petals and the size of the slits 48 defining the petals 45 create an irregular shaped opening 30. Circular as used in relationship to the insertion end 26 opening 30 means that a regular curved figure described by the free ends 46 of the petals 45 is in this case circular as opposed to elliptical.
(115) In many embodiments the insertion end 26 is formed by from 3 to 6 or 3 to 5 petals 45, e.g., 3, 4 or 5 petals 45.
(116) The ejection force of a tampon applicator 12 of the present disclosure is no greater than 25 oz. In many embodiments the required ejection force is from about 8 to about 20 oz. In many preferred embodiments the required ejection force is from about 10 to about 20 oz, or from about 10 to about 15 oz, for example, from about 10 to about 12 oz.
(117) In many embodiments the tampon applicator 12 has a taper ratio of from about 1.3 to about 2.5, for example a taper ratio of at least 1.5, 1.6 or 1.7, up to about 2.3, 2.2 or 2.0, and in many embodiments the tampon applicator 12 has a degree of closure of from about 0.1 to about 0.25, from about 0.1 to about 0.20, e.g., from about 0.12 to about 2.0 or about 0.14 to about 0.25.
(118) The taper of the tampon applicator 12 is related to the outside dimensions 14b of the applicator 12, while the degree of closure is related to the interior dimensions 14a. The direct relationship between taper and degree of closure is through the thickness 14c of the barrel 14 wall where the main body region 36 adjoins the insertion end 26 and the thickness 14c of the petals 45 at their free ends 46. The thickness 14c of the barrel 14 wall and the petals 45 of the present disclosure are typical of those encountered in the art, and will vary somewhat.
(119) As discussed above, in light of reduction in ejection force due to the present the reconfiguration of the insertion end 26, it may be possible to prepare applicators 12 with somewhat thicker petals 45, which may prevent unwanted deformation of the insertion end 26. For example, while in many embodiments the petals 45 will have a thickness in the ranges found in U.S. Pat. No. 8,444,590, e.g., about 0.004 inches to about 0.022 inches, about 0.008 inches to about 0.018 inches, or about 0.009 inches to about 0.013 inches, many embodiments the thickness of the petals 45 may be at the higher end of such ranges. In some embodiments the petals 45 can be thicker than those of U.S. Pat. No. 8,444,590, for example, up to 0.025, 0.03 or 0.035 inches.
(120) Generally, the petals 45 have a high degree of thickness uniformity. Petal 45 thickness 14c uniformity across the entire area of each petal 45 is advantageous for several reasons. First, it can result in processing efficiencies when making the applicator 12. Secondly, a uniform thickness 14c ensures that each petal 45 will function properly both during storage and shipment of the applicator 12, and more importantly during use by a woman. In addition, the uniform petals 45 may be more aesthetically pleasing to the consumer.
(121) In many embodiments of the present disclosure, the thickness 14c measured at any point on a given petal 45 does not vary more than about 25% across the entire area of the petal 45, often the thickness 14c does not vary more than about 10% across the entire area of the petal 45 and in some embodiments the thickness 14c does not vary more than about 2% across the entire area of the petal 45.
(122) The barrel 14 and the plunger 16 may be prepared from the same material or from different materials, and likewise for embodiments with a two-piece plunger 16 having an inner plunger 18 and an outer plunger 20, the materials. For example, the tampon applicator 12 plunger 16 and/or barrel 14 may be prepared from cardboard, but in many embodiments, at least a portion of the tampon applicator 12, e.g., the barrel, or the entire applicator is prepared from a composition comprising a thermoplastic polymer, an elastomeric polymer, or a mixture of a thermoplastic and elastomeric polymer. For example, the tampon applicator may be made from a polymer composition comprising one or more synthetic polymers and/or naturally occurring materials such as a polyolefin polymer or copolymer, polyester, polyamide, polystyrene, polyvinyl chloride, polyacrylate, polymethacrylate, polyvinyl alcohol, polylactic acid or moldable starch. Most often the polymer will comprise a thermoplastic polymer or a blend of a thermoplastic and elastomeric polymer, for example, the polymer often comprises a polyethylene, low density polyethylene, high density polyethylene, near low density polyethylene, polypropylene, or a copolymer comprised of ethylene, styrene, isoprene or butadiene monomers. In many embodiments the organic polymer comprises low density polyethylene, high density polyethylene or a mixture of low density polyethylene and high density polyethylene.
(123) In some embodiments, the organic polymer comprises a blend of a polyethylene, e.g., low-density polyethylene and a thermoplastic elastomer. For example, the organic polymer may comprise a blend of about 50 wt. % to about 90 wt. %, e.g., about 80 wt. %, low-density polyethylene and about 50 wt. % to about 10 wt. %, e.g., about 20 wt. %, thermoplastic elastomer, based on a total weight of the composition. On useful thermoplastic elastomer is a tri-block (terpolymer), having an A-B-A configuration of monomers, in which monomer B is not the same as monomer A. Typically the blocks comprise styrene, butadiene, or isoprene monomers. Other classes of useful thermoplastic elastomers include, for example, thermoplastic polyurethane elastomers.
(124) When the tampon applicator 12 comprises a thermoplastic or elastomeric polymer composition, the composition will also typically comprise one or more of a variety of common additives, such as processing aids, stabilizers, lubricants colorants etc. For example, the polymer composition may comprise one or more plasticizers, compatibilizers, flow modifiers, antioxidants, antistatic agents, fillers, reinforcements, surfactants, thermal stabilizers, impact modifiers, processing aids such as stearate salts, lubricants, flame retardants, biocides, antiozonants, blowing agents, anti-foaming agents and the like. In order to possess or maintain the proper softness and/or lubricity the composition typically contains at least 0.05 of a lubricant, for example, a lubricant comprising a fatty acid amide such as erucamide, oleamide, stearamide, stearyl erucamide, bis-erucamide, ethylene bis stearamide, ethylene bis oleamide.
(125) Some embodiments of the present disclosure provide a tampon assembly 10 comprising a tampon applicator 12 of the present disclosure and an absorbent tampon pledget 22 contained within the barrel 14 (prior to ejection from the barrel 14 as used inside the body of a user). The pledget 22 may have a shape that corresponds with the interior geometry 14a of the main body region 36 of the barrel 12, or at least a portion of the pledget 22 may be shaped to correspond with at least a portion of the interior geometry 14a of the insertion end 26 as in U.S. Pat. No. 9,192,522. Suitable materials for forming a pledget 22 include, for example, cellulosic; rayon; cotton; pulp; superabsorbent, such as Oasis; absorbent foam, such as hydrophilic polyurethane foam; or any combinations thereof.
(126) The reconfigured insertion end 26 of the present disclosure furthers the attempts to find a proper balance of both ejection force and petal 45 stability, particularly stability in the free petal ends 46. There is no particular limitation placed on the main body region 36 of the barrel 14 or the plunger 16, each of which may encompass any of the variety of features known in the art.
(127) In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one. In this document, the term “or” is used to refer to a nonexclusive or, unless otherwise indicated. It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the present disclosure should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc., as they may be included, are used merely as labels, and are not intended to impose numerical requirements on their objects. In the Detailed Description provided above, various features may be grouped together to streamline the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter may lie in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.