Withdrawal Strings for Tampons

BACKGROUND OF THE INVENTION

1. Field ofthe Invention This invention relates to an improved tampon and, more specifically, to improved withdrawal strings for tampons. 2. Prior Art Prior art tampons normally comprise a cylindrical pledget of a non- irritating, absorbent material such as cotton or rayon formed by compression into an easily insertable shape prior to use. A withdrawal string is typically attached to the pledget during construction to facilitate the removal of the tampon from the vagina following its use. The absorbent characteristics of a particular tampon depend upon, among other things, the geometry of the pledget as well as its method of fabrication and the material thereof. Those tampons enjoying success in the marketplace permit the continual absoφtion of blood and other vaginal discharge even in the presence of clotting blood. Thus, modern tampons have a great capacity for absoφtion of blood. Unfortunately, the withdrawal string that is used to retrieve the tampon from the vagina is typically made of an absorbent or intertwined material which, when wetted by urine, swimming, perspiration and the like serves to wick or conduct fluids present in the tampon's pledget into the tampon user's undergarments or to surroundings (mattress, clothes, furniture, etc.). Thus, not only are tampons changed more frequently, but undergarments and surroundings are soiled and/or damaged more regularly than would otherwise be the case in the absence of such conduction or wicking. Suφrisingly, the development of a non- wicking. non-absorbent tampon withdrawal string has received no attention. Indeed, the problem of wicking fluids either into or out of the vagina has not been addressed in the art. As used herein, the term "wicking" refers to the physical transport of fluid into or out of the vagina by a

withdrawal string. Commonly, cotton is used as a withdrawal string. Rayon, which is also frequently used for the tampon pledget itself, has also been recommended for use as a withdrawal string. Such strings, as mentioned above, suffer from an inescapable tendency to conduct, or wick, fluids. Since the withdrawal string extends from the pledget to the outside of the vagina, such conduction is undesirable.

Glassman, in US Patent 5,047,024, describes a withdrawal string that is double-stranded and of an unknown material. While no mention of the specific material is made, if the withdrawal string material is absorbent, it would wick fluid from or into the vagina. If it is not absorbent, the intertwined, double-stranded nature of the withdrawal string, would, by capillary action, also conduct fluid from or into the vagina. Hinzmann et al., in US Patent 5,004,467, describes a tampon comprising a cylindrical pledget and a withdrawal string. Hinzmann provides no characterization of the physical, chemical or mechanical properties of the material preferably comprising the withdrawal string. Walton, et. al., in US Patent 4,627,849, describes a tampon that utilizes an absorbent rayon withdrawal string. Such strings would conduct fluid from the vagina. US Patents 4,222,381 and 4,018.225 describe further embodiments of vaginal tampons employing withdrawal strings of unknown composition. It is desirable to provide a tampon that has a withdrawal string that does not conduct fluids from the vagina. It is also desirable to provide a withdrawal string for a tampon which prevents "reverse wicking" of exogenous fluids into the vagina as may occur when the wearer engages in any water activity such as swimming, or in strenuous activities producing perspiration. "Reverse wicking" of exogenous fluids will saturate or "water-log" a tampon ^' s pledget necessitating immediate change. Premature removal of an unsaturated tampon as well as the belated changing of an oversaturated tampon, at the very least, creates waste in the first instance and damage to garments in the latter case. In a worst case scenario, constant removal of undersaturated tampons may cause tiny abrasions to the user/wearer ^' s vaginal mucosa (vaginal lining) which provide an entrance point for the potentially pathogenic

organisms and lead to toxic shock syndrome. Catamenial or medical tampons may also incoφorate means by which the user/wearer can inspect and judge a tampon pledget's blood saturation level before removing the tampon, thereby enabling the user/wearer to change the tampon in a timely manner to maximize absorbence of blood by the pledget while preventing oversaturation thereof. The foregoing objectives are achieved by the improved withdrawal strings disclosed in the present invention.

SUMMARY OF THE INVENTION A first embodiment of this invention is an improved tampon having a withdrawal string which does not conduct vaginal or menstrual discharge. The withdrawal string is preferably a single-stranded, non-absorbent, homogenous filament having unitary construction. It is a further object of the invention to provide a withdrawal device for a tampon which is operable for providing an indication of a tampon pledget's blood saturation level. This second embodiment is useful for removing the guesswork from tampon use, and allowing the user/wearer to visually see the tampon pledget's saturation level so one may judge readiness for a change. Two examples of embodiments showing indicating withdrawal/removal devices are shown in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partially cutaway perspective view of a prior art absorbent pledget tampon 10 with the proximal end 11 of a withdrawal device 12 non-releasably attached to the tampon's pledget portion 13, wherein the withdrawal device prevents wicking of blood. Figure 2 is a cross-sectional view of a tampon 20 showing a prior art absorbent pledget 21 , having a withdrawal indicator device 22 which has one proximal end 23 which is open or permeable to blood (not shown) within the pledget 21 and a leakproof distal end 24 which is closed or sealed, and an inner indicating core 25 therebetween and coextensive with the withdrawal device.

Figure 3 shows a cross-sectional view of a tampon 30 also showing prior art absorbent pledget 31, having a withdrawal indicator device 32 which has one proximal end 33, an inner indicating core 35, and a distal end 34 which is transparent and optionally includes a semi-spherical terminal lens 36 providing optical communication between the interior of the pledget and the distal end 34 of the withdrawal device 32.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning first to Figure 1 , a tampon, generally indicated at the numeral 10. consists of an absorbent, usually cylindrical or rectangular pledget 1 1 non- releasably attached to a withdrawal string 12. The withdrawal string 12 may be attached to the pledget by a variety of means such as is well known in the prior art. Friese, for example, in US Patent 4,490,894, shows an apparatus for attaching a withdrawal string to a tampon. The withdrawal string 12 comprises an elongate, flexible hydrophobic monofilament such as single-stranded dacron or siliconized dacron. The hydrophobic composition and the monofilamentous unitary construction of the withdrawal string 12 prevents the unwanted conduction of menstrual/vaginal fluids to the exterior of the vagina by absoφtion, wicking and capillary action. Such a non-wicking withdrawal string also prevents reverse wicking as mentioned earlier. The above-described preferred embodiment provides a tampon which materially improves the performance, comfort and utility of the tampon for preventing the conduction of menstrual and/or vaginal discharge into undergarments during use. Additionally, the monofilamentous withdrawal string will prevent reverse wicking. The foregoing preferred embodiment is exemplary and presented to illustrate the invention. not limit it. It is within the scope of this invention to include any withdrawal string which is non-wicking to aqueous liquids such as menstrual or vaginal discharge, urine, pool water, sea water, perspiration or other liquids and incapable of conducting such fluids along its length by capillary action. Suitable materials for the withdrawal string include, but are not limited to monofilamentous organic polymers having a homogenous composition or an absorbent material, such as cotton which has been coated with a hydrophobic outer layer.

Turning now to figures 2 and 3. generic prior art absorbent pledgets 21 and 31 which form and are common to prior art tampons, are shown for illustrative puφoses

only, and not considered a part of the invention. The withdrawal/removal devices 22 and 32 shown in figures 2 and 3 respectively are enhancements of the foregoing non- wicking, non-absorbent withdrawal device 12, the enhancement being the incoφoration of a pledget blood-saturation indicating means thereto. These withdrawal devices 22 and 32 may be transparent, semi-transparent, colored, or opaque with a transparent window on or near the proximal end 24 and 34 thereof through which the user may view the saturation level of the pledget. The open or unsealed proximal ends 23 and 33 ofthe withdrawal devices 22 and 32 are adapted to allow either fluid contact (22) or optical communication (32) between the inner, indicating cores 25 and 35 and blood (not shown) which may be present in the absorbent pledgets 21 and 31. Both withdrawal devices 22 and 32 have closed or sealed distal ends 24 and 34 which will prevent blood or material present in the inner indicating cores 25 and 35 and the absorbent pledgets 21 and 31 from coming in contact with the liser/wearer ^' s skin, undergarments, bedding, clothing, etc. The indicating withdrawal device 32 of Figure 3 may optionally include a closed or sealed distal end 34 having a transparent semi -spherical lens formed thereon providing a "lens" for wide angle viewing of the condition of the pledget 31 via the core 35. The inner indicating core 25 and 35 ofthe monofilament withdrawal/removal device 22 and 32 are shown in Figures 2 and 3. The core 25 chosen can be operable for either (a) absorbing blood and transporting the blood along the length of the core

25 to the distal end 24 thereof and into view ofthe user/wearer; or (b) utilize capillary action to transport blood along its length into view: or (c) be saturated or treated with, or made of a material that undergoes a color change responsive to blood contact or the degree of pledget blood saturation: The inner indicating core 35 may comprise at least one fiber optic enabling the user/wearer to visually perceive when blood has

saturated the pledget by visual inspection ofthe distal end 34 ofthe core 35 within the withdrawal device 32.

What I claim is: