US3520302A

US3520302A - Tampon

Info

Publication number: US3520302A
Application number: US619509A
Authority: US
Inventors: John Leslie Jones
Original assignee: Kimberly Clark Corp
Current assignee: Kimberly Clark Corp
Priority date: 1967-02-13
Filing date: 1967-02-13
Publication date: 1970-07-14
Anticipated expiration: 1987-07-14

Description

J. L. JONES July M, 1970 'TAMPON Filed Feb. 13, 1967 INVENTOR United States Patent Oifice 3,520,302 Patented July 14, 1970 3,520,302 TAMPON John Leslie Jones, Pasadena, Calif., assignor to Kimberly- Clark Corporation, Neenah, Wis., a corporation of Delaware Continuation-impart of application Ser. No. 350,193, Mar. 9, 1964. This application Feb. 13, 1967, Ser. No. 619,509

Int. Cl. A61f 13/20 US. Cl. 128-285 9 Claims ABSTRACT OF THE DISCLOSURE A one-piece regenerated cellulose sponge tampon having a withdrawal string coaxially disposed through the length of the tampon body and permanently bonded to the tampon along its length, with an end of the strip extending beyond one end of the tampon to provide handle means.

This application is a continuation-in-part of my copending application on tampons, Ser. No. 350,193, filed Mar. 9, 1964, now US. Pat. No. 3,342,237. My present invention relates to new and useful improvements in a menstrual tampon.

The principal object of my invention is to provide a menstrual tampon containing a coaxial withdrawal string permanently bonded therein.

Further objects and advantages of my invention will become apparent in the following description, to be read in connection with the accompanying drawings.

My earlier copending application, Ser. No. 350,193 teaches a dry, radially compressed, regenerated fine pore cellulose sponge, having a coaxial withdrawal string disposed in the length of the cylinder, and forming a menstrual tampon.

FIG. 1(a) is a perspective view of a radially compressed menstrual tampon of my invention. FIG. 1(b) is a perspective and partial sectional view of an uncompressed, or fully expanded, menstrual tampon of my invention, showing details of my withdrawal string structure. The relative diameters of the tampons of FIG. 1(b) and FIG. 1(a) show the relative diameter of my tampons before and after radial compression of the one-piece, regenerated cellulose sponge. FIG. 1(0) shows enlarged details of my withdrawal string structure, in use in my tampon.

Referring to FIG. 1(a) in detail the menstrual tampon 1 comprises a dry, radially compressed, minimum pore volume, regenerated cellulose cylinder 2, and withdrawal string 3 coaxially located in and along the cylinder axis length and extending beyond the cylinder, forming a string handle 6. FIG. 1(b) shows more detail of my tampon invention, being a perspective and partial cross section view of the dry, fine-pore, expanded, regenerated cellulose, polygonal cross section cylinder 2', prior to radial compression to form the cylinder 2. The coaxially located withdrawal string 3, shown in the cylinder 2', is also coaxially surrounded by a permanent bond means 4 extending the length of the cylinder 2. The cylinder 2' has area ends 5 and 5'. The permanent bond means 4 is an annular cylindrical shaped zone which is shown in enlarged cross sectional detail in FIG. 1(a), taken through 1c1c of FIG. 1(b).

I have found that the permanent bond means 4 can comprise a thermally fused bond formed between a fused yarn structure of the withdrawal string and the regenerated cellulose sponge structure. The fused yarn is cooled to room temperature to form a permanent bond means 4. I have also found that the permanent bond means 4 can be formed by a hot melt adhesive, cooled to room temperature to form a bond between the withdrawal string and the regenerated cellulose sponge structure. My permanent bond means 4 provides a bond between the withdrawal string and the regenerated cellulose sponge which will withstand the stresses of commercial storage conditions, immersion in menstrual fluid and the force required to remove a wet used tampon from a vagina.

I have found that a bifilament withdrawal string made of 50 wt. percent regenerated cellulose rayon yarn-50 wt. percent cellulose acetate yarn, made in a conventional 2 ply with a wet strength of 6.5 lbs., is a representative bifilament yarn or string useful in my invention.

By using such an above described bifilament yarn as the withdrawal string 3 in the cylinder 2, I may then thermally fuse or melt the cellulose acetate yarn in the string 3. On cooling the fused yarn, the solidifying cellulose acetate yarn melt will bond to both the rayon yarn and the regenerated cellulose sponge, particularly if the sponge is rapidly radially compressed, before the fused yarn begins to solidify. I use a second non-melting or nonthermally decomposing yarn as a second filament in the bifilament yarn structure, to provide a second strength member of the bifilament yarn which will not fuse. A fusible yarn used alone may stress crack on cooling, possibly breaking off the withdrawal string on application of the force required to withdraw a used tam pon from a vagina, the non-fusing yarn will not break ofl.

Cotton yarn plied with cellulose acetate yarn is also a suitable bifilament yarn construction for my withdrawal string 3. Cotton yarn plied with polyvinyl chloride yarn; also regenerated rayon plied with nylon yarn, or like combinations of fusible yarns plied with non-fusible yarns can be used to make my withdrawal string 3. The bifilament yarns form a permanent bond means 4 on application of the required heat of fusion for the fusible yarn, followed by rapid radially compressing the cylindrical tampon, and allowing the fused yarn to cool and solidify.

I have likewise found that a hot melt adhesive can coat, or impregnate and coat, a non-fusible string, forming a string composition which is not melted or sticky at body temperature, or soluble in menstrual fluid. A typical mercerized cotton string impregnated and coated with a plasticized cellulose diacetate composition can be used to form a suitable string 3. The above cotton string, with the plastized cellulose acetate coating thereon. is preheated prior to location in the sponge billet, but not to the coating fusion temperature. After locating the preheated, coated cotton string in the sponge cylinder, both the sponge cylinder 2 and the coated string are further heated above the fusion temperature of the cellulose acetate coating and then rapidly compressed. The compressive force aids the formation of a strong permanent bond means 4 between the withdrawal string 3 and the sponge cylinder 2, when the string 3 and sponge cylinder 2 are cooled to room temperature.

Other non-fusible yarns or strings, selected from cotton, linen, hemp, regenerated cellulose rayon or the like, can be combined with hot melt adhesive coatings. Suitable hot melt coating are plasticized vinyl chloride resin, plasticized vinyl acetate-vinyl chloride copolymer, plasticized collulose acetate butyrate, polyethylene or the like fusible coatings. My hot melt coatings should not fuse or lose bonding strength at human body or commercial storage temperatures, yet should be readily fusible at the higher temperatures to which the regenerated cellulose spronge can be heated without decomposing the sponge. Controlled heating of all bond components can effect a good bond between the sponge, the cooled and solidified hot melt coating, and the non-fusible, yarn or string.

My invention uses dry, expanded, regenerated cellulose sponge of fine pore structure as a basic raw material. I

3 defined expanded, fine pore regenerated cellulose sponge as the dry sponge of fully distended pore structure, not yet subjected to a compressive force which collapses the pore dimensions.

Typically, my white spronge has pores in the dry, expanded state ranging from 0.5 to 2.0 mm. diameter and the like, and a 1 mm. pore diameter is common. A typical dry, expanded regenerated cellulose sponge density is 0.029 g./cc. When fully saturated with water the typical regenerated cellulose sponge density is 1.00 g./cc., so a fully saturated wet sponge may absorb approximately 0.97 g./cc. of Water or relatively similar density menstrual fluid.

My dry, radially compressed minimum pore volume, regenerated cellulose tampons, having coaxially located withdrawal strings permanently bonded the length of the sponge cylinder, have been tested in menstrual absorption application with very favorable results. The small diameter radially compressed sponge cylinder does not cause discomfort in females and is easily inserted by a correspondingly sized conventional pair of telescoping paper tubes. The sponge tampon expands on absorption of menstrual fluid and is removed by pulling on the permanently bonded withdrawal string 3, or the like. The wet sponge is soft and pliable, and does not damage or tear tissue. If the menstrual fluid is insutficient to fully wet the tampon, the dry portion of the tampon does not expand, and hence is easily removed from the vagina.

Typical absorption test data is listed below in Table I. The data clearly establish the use of my tampon to absorb a daily menstrual flow at the range of normal flow rate in a normal use pattern, without discomfort. In addition, the relative small diameter of my radially compressed tampons are supported in Table II by the comparison of my sponge tampon diameters, before and after radial compression to a minimum pore volume. I compare both dry, expanded regular hexagon polygons and circular cross section tampons, since for my purpose I classify a circle as an infinite sided polygon. The radial compression ratio is substantially constant, independent of the tampon expanded cross section diameter.

TABLE I.-TAMPON PERFO RMANCE Dry blank \vt.=0.9 gram 0 P.M 0 PJVI Test N0. 2.Tampon size: in. round X 2% in. long Dry blank wt.=0.8 gram I claim:

1. A menstrual tampon comprising: a dry, radially compressed, minimum pore volume, regenerated cellulose cylinder; a withdrawal string coaxially disposed through the length of said cylinder and extending from one end of said cylinder to form a handle means; and a permanent bond means coaxially surrounding said string and securing said string to said cylinder along the length of said cylinder.

2. The menstrual tampon of claim 1 in which a thermally fused bond secures said string to said cylinder.

3. The menstrual tampon of claim 1 in which an adhesive bond secures said string to said cylinder.

4. A menstrual tampon comprising: a dry, expanded, fine pore, regenerated cellulose sponge, polygonal crosssection cylinder; a Withdrawal string coaxially disposed through the length of said cylinder and extending from one end of said cylinder to form a handle means; and a permanent bond means coaxially surrounding said string and securing said string to said cylinder along the length of said cylinder.

5. The menstrual tampon of claim 4 in which a thermally fused bond secures said string to said cylinder.

'6. The menstrual tampon of claim 4 in which an adhesive bond secures said string to said cylinder.

7. The menstrual tampon of claim 2 in which said string is comprised at least in part of fusible material.

8. The menstrual tampon of claim 7 in which said string comprises a bifilament yarn in which one filament is fusible and one filament is non-fusible.

9. The menstrual tampon of claim 3 in which said string is comprised of non-fusible yarn coated with a hot melt adhesive.

References Cited UNITED STATES PATENTS 2,298,752 10/1942 Crockford 128263 2,458,685 1/1949 Crockford l28263 2,880,726 4/1959 Stieg 128285 2,884,925 5/1959 Meynier 128285 3,347,237 10/1967 Jones 128285 CHARLES F. ROSENBAUM, Primary Examiner US. Cl. X.R.