Textile Tampon Having A Resilient Foam Core

Abstract

A textile tampon having a compressible resilient spongiform core within the textile mass to cause the textile mass to expand laterally in the vagina so that the tampon conforms to the cross section of the vagina, thereby forming an intimate contact between the textile mass and the vaginal walls.

Description

FIELD OF THE INVENTION

This invention relates generally to absorbent catamenial tampons and more particularly concerns tampons which, in a dry state, are compliant to and deformable by pressures exerted thereon by the vagina.

DESCRIPTION OF THE PRIOR ART

Absorbent textile tampons as generally known are highly compressed bundles of textile fibers, and they retain their highly compressed form as a result of entanglement and hydrogen bonding between adjacent fibers. The hydrogen bonding results from heavy compression and moisture history of the textile fibers. Such a tampon remains highly compressed until it is wetted by a fluid, for example, the fluid which it is to absorb. The wetting releases the hydrogen bonds so that the textile fibers can expand somewhat in the direction opposite the compression originally placed upon the textile fibers. Thus textile tampons as generally known exhibit wet expansion.

Wet expansion by itself, as has been recognized by those of ordinary skill in the art, is not sufficient to provide complete protection against "bypass." Bypass occurs when the tampon cross section, after insertion in a cavity such as a vagina, is smaller than that cavity. The fluids draining through that cavity can follow a path which circumvents the dry tampon. Thus, the fluids can flow the length of the cavity without contacting the tampon. Therefore, the tampon which is to give protection against bypass must be expansible without depending on contact with the fluids which it is to absorb.

It is known in the art to make tampons which will give support to the cavity wherein it lies. Such a tampon is taught in U.S. Pat. No. 688,188, issued to Magoris on Dec. 3, 1901 wherein a somewhat elastic and basically nonabsorbent material such as wool is placed within a soft fabric sack made from a material such as muslin. The wool provides a cushioned filling for the sack.

Other types of support tampons are known in the art, such as the tampon taught in U.S. Pat. No. 1,401,358, issued to Peterkin on Dec. 27, 1921, wherein a nonabsorbent element such as lambswool is an outer member and acts as a sheath or a support for an absorbent element which is the inner member. The outer member has a central recess and the inner member is concentric with and secured to the outer member. The inner member being the absorbent element can be made of absorbent cotton.

It is also known in the art to make catamenial devices having wet expanding cores. Such a device is taught in U.S. Pat. No. 2,328,795, issued to Finks on Sept. 7, 1943, wherein a device is taught having an absorbent and moisture expansible compressed inner member, a permeable intermediate member for maintaining the inner member in a compressed condition, and an uncompressed or lightly compressed outer layer of absorbent material. It is also taught that the inner layer may be omitted, in which case the outer layer would be rolled more tightly about the core.

In addition, the art teaches multi-component devices which must be assembled by the user, inserted digitally, and expanded by digital movement after the device has been inserted in the cavity. Such a device is taught in U.S. Pat. No. 3,054,403, issued to Baker on Sept. 18, 1962, wherein an apparatus is taught comprising a hollowed conical pad which is fitted over a hollow conical injector, the injector being of flexible rubber which is nonabsorbent and having foramens at the top and side forming canals extending through to the cavity of the injector.

The art also teaches compressed textile tampons having a separate and distinct compressed, wet expansible core, for example, see U.S. Pat. No. 3,079,921, issued to Brecht et al on Mar. 5, 1963 which teaches a tampon formed of a plurality of layers of absorbent material and a highly compressed moisture expandable material, the highly compressed material being interspersed between the layers of absorbent material such that it is preferably completely enclosed by the absorbent material. The highly compressed material is also preferably absorbent, e.g., an absorbent sponge of regenerated cellulose. These tampons are intended to provide a more effective barrier to the flow of menstrual fluid by providing a tampon which when moistened expands, particularly in a direction more or less diametrically, to a size considerably larger than its compressed size to contact more of the surface of the vaginal walls.

However, none of the prior art tampons of which the applicant is aware provides a flexible fibrous absorbent body having a resilient, dry expanding, spongiform core which is substantially enclosed by the fibrous body to provide a tampon which can be resiliently compacted and will expand from its resiliently compacted condition without the presence of fluids.

OBJECTS OF THE INVENTION

It is an object of this invention to provide a tampon which is highly absorbent and dry expanding.

It is another object of this invention to provide a tampon which is also soft and conformable.

It is a further object of this invention to provide a textile tampon having high capacity which can be resiliently compacted and will dry expand from its resiliently compacted state.

It is also an object of this invention to provide a textile tampon having a high degree of dry expansion.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a tampon having a radially expandable, flexible, fibrous, absorbent body and a resilient, dry expanding spongiform core wherein the core is substantially enclosed by the body. The body is expansible in a dry condition from a resiliently compacted condition by the resilient, dry expanding core to establish contact with the vaginal walls.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing and distinctly claiming the subject matter which is regarded as forming the present invention, it is believed that the invention will be better understood from the following descriptions which are taken in connection with the accompanying drawings, in which the thickness of some of the materials are exaggerated for clarity and in which:

FIG. 1 is a perspective view of a tampon of this invention before any resilient compaction has been exerted on the tampon;

FIG. 2 is a perspective of the tampon of FIG. 1 in a partially compacted state;

FIG. 3 is a cross section through the tampon of FIG. 2 along the line 3--3;

FIG. 4 is a cross section similar to that of FIG. 3, but showing a different core configuration;

FIG. 5 is a perspective view, partially fragmented, of another tampon of this invention at one stage in its construction;

FIG. 6 is a perspective of the tampon of FIG. 5 in a further stage of its construction;

FIG. 7 is a perspective of another form of a tampon of this invention in its undeformed configuration;

FIG. 8 is a perspective view of the tampon of FIG. 7 in approximately its in-use configuration;

FIG. 9 is a perspective of another form of the tampon of this invention in a partially deformed configuration;

FIG. 10 is a cross section of the tampon of FIG. 9 along line 10--10;

FIG. 11 is an elevational cross sectional of an alternate embodiment of a tampon of this invention; and

FIG. 12 is a side cross section of a tampon of this invention in a tubular inserter.

DETAILED DESCRIPTION OF THE INVENTION

The tampon in this invention is generally a textile tampon having a highly compressive and resilient spongiform or foam core. The core is dry expanding and necessarily so when the tampon is resiliently compacted. Dry expanding as used herein is intended to mean expandable from a compacted condition, e.g., the condition of a tampon of this invention as when within a telescoping tubular inserter such as is shown in FIG. 12, without relying on the presence of fluid to release any set which may have taken place within the absorbent body while it was compacted.

Referring first to FIG. 12, a transverse cross section, i.e., the cross section perpendicular to the longitudinal axis, of the tampon 46 should be greater than the transverse cross sectional area enclosed by the outer tube 44 of inserter 43 in that portion of the outer tube 44 corresponding to the tampon transverse cross section, said correspondence occurring when the tampon 46 is within the outer tube 44. Preferably, the combination of the fibrous body and the core of the tampon 46 and the inside diameter of the outer tube 44 is such that the tampon 46 is optimally resiliently compacted, i.e., the fibrous body remains flexible and compliant so as to conform to irregularities within the vagina and the core has maximum dry expansion in that it is neither compacted so much that permanent set takes place nor compacted so little that its dry expansion is minimal. Also preferably, the uncompressed transverse cross section of the resiliently compacted core is greater than the transverse cross sectional area enclosed by the outer tube 44. The core being larger than the inside diameter of the outer tube 44 insures that the core will be at least moderately compressed when the tampon 46 is resiliently compacted within the outer tube 44.

Referring now to FIG. 1, there is shown one embodiment of a tampon of this invention before it is deformed or compacted. Layer 22 is a resilient, dry expanding core and layer 21 is a fibrous absorbent body. The core and fibrous body may be held together by looping a string 23 through the center as shown in FIG. 1 such that the string 23 can also function as a withdrawal string. The core 22 is shown slightly smaller than the fibrous body 21. This difference in size is not absolutely necessary but does result in a tampon of this invention wherein the core is substantially enclosed by the fibrous body, which can be advantageous.

To put the tampon of FIG. 1 in a configuration wherein it can be inserted into a vagina, the absorbent materials are radially compacted, i.e., gathered upwardly and inwardly such as is shown in FIG. 2. The shape of the tampon in FIG. 2 is an intermediate shape which may be the approximate compaction of the tampon when in place in the vagina. The tampon would be resiliently compacted more than is shown in FIG. 2 in order to place it within a typical telescoping tubular inserter such as inserter 43 shown in FIG. 12 to achieve easy comfortable placement of the tampon. After the tampon is released from the inserter, it dry expands.

FIG. 3 being a cross section of FIG. 2 shows the bending of the absorbent materials at the center thereof. Although the bending of the core at the center develops tension and stress in the core material to provide some spreading effect when the tampon is released from an inserter, the primary dry expanding force of the core results from the compression developed in the core when the tampon is radially resiliently compacted to fit within a tubular inserter.

The core can be made in various shapes, and an alternate embodiment is that of FIG. 4 wherein the core 24 had a tubular shape before the tampon was partially radially compacted. A tubular core 24 will also provide dry expansion to the tampon because it is resiliently compacted when the tampon is placed in an inserter for introduction into a vagina. Upon release from the inserter, the core 24 dry expands from its resiliently compacted configuration, thereby spreading the fibrous body 21.

In the tampon as shown in FIG. 5, cylindrical core 26 is rolled within a fibrous body 25 to form a "log." Adhesive means such as glue can be placed in the lap joint of the fibrous body 25, i.e., between the superposed portions of the fibrous body 25, to maintain the lap joint and prevent the assembly of the core 26 of the fibrous body 25 from coming apart. A string 27, shown in FIG. 6, can then be secured about the log of FIG. 5 at the approximate midpoint thereof. This string 27 can provide a withdrawal means to remove the used tampon from the vagina. The ends of the log of FIG. 5 are then brought together to form a U-shaped tampon such as shown in FIG. 6. The U shaped tampon is then radially compacted to place it within a tubular inserter and the resiliently compacted tampon upon release from the inserter into the vagina will dry expand.

Another embodiment of a tampon of this invention is as is shown in FIGS. 7 and 8 wherein a resilient dry expanding core 28 is superposed on a fibrous body 29 and the fibrous body and the core may be attached by threading a withdrawal string 30 through the fibrous body 29 and the core 28 at their approximate center as shown in FIG. 7. The fibrous body 29 and the core 28 have approximately the same shape and in this embodiment, that shape is two trapezoids having a common short base.

The ends of the tampon of FIG. 7 are then deformed upwardly to form a U as shown in FIG. 8. The tampon is then radially resiliently compacted to fit it within a tubular inserter so that it may be placed easily and comfortably into a vagina. The resilient compaction imposes compressive stresses within the core 28 to provide dry expansion of the core 28 which causes expansion of the fibrous body 29, when the tampon is released from an inserter. Although FIGS. 7 and 8 show the core 28 being coextensive with the fibrous body 29, the core 28 can be made slightly smaller than the fibrous body 29 such that the core is substantially enclosed by the fibrous body when the tampon is subjected to a slight amount of compaction.

Another embodiment of a tampon of this invention is shown in FIGS. 9 and 10 wherein a laminate of alternating layers of absorbent body 35, 36, 37 and 38 and core 31, 32, 33 and 34 is formed. This laminate may be held together by threading a withdrawal string 39 through the laminate along its approximate longitudinal axis as shown in the FIGS. 9 and 10 or by other attaching means. The tampon is then radially resiliently compacted -- a slight amount of compaction is shown in FIGS. 9 and 10 -- to fit the tampon within a tubular inserter. In this embodiment also, the compaction imposes compressive stresses in the core to provide dry expansion of the tampon when it is released from an inserter.

Although it is not absolutely necessary to graduate the size of succeeding layers of the tampon from one end to the other, i.e., generally smaller on one longitudinal end of the tampon and larger on the other longitudinal end, it is preferable to do so in order to achieve a tampon having a more uniform cross section and density in its compacted state. Also, such a graduation in size of the layers as shown in FIGS. 9 and 10 will provide a larger diameter at the proximal end or top of the tampon and, therefore, provide a tampon having the potential to fill a larger cross section. The proximal end is that end of the tampon nearest the cervix when the tampon is in use. An advantage of having the proximal end as the largest layer is that it is compacted the most and, therefore, has the greatest potential for dry expansion.

Although the FIGS. 9 and 10 show each core layer being slightly smaller than its cooperating fibrous absorbent body layer, whereby the core layers are substantially enclosed by the absorbent body layers when the tampon is in a compacted state, each core layer need not necessarily be smaller, and can, if such is desirable, be the same size as its cooperating fibrous body layer. In this description, the cooperating fibrous body layer for a core layer is the fibrous body layer immediately below the core layer, e.g., the cooperating fibrous absorbent body layer for core layer 31 is layer 35.

FIG. 11 shows another embodiment of this invention in cross section wherein both the fibrous absorbent body 40 and the core 41 are similarly shaped hollow cones. The core 41 is located within the fibrous body 40 and a string 42 can be threaded through the apex of both the core 41 and the fibrous body to attach the two and also provide a withdrawal means for the tampon. The core 41 and the fibrous body can also be attached by other means well-known to men of ordinary skill in the art, such as adhesives.

FIG. 12 shows a tampon 46 of this invention resiliently compacted in a constraining means such as the outer tube 44 of a telescoping tubular inserter 43. Telescoping tubular inserters are well-known to men of ordinary skill in the tampon art. A typical telescoping tubular inserter is taught in detail in U.S. Pat. No. 3,628,533, issued to Loyer on Dec. 21, 1971. The inserter 43 has an ejection means such as inner tube 45 to push tampon 46 out of outer tube 44 and into a vagina after the outer tube 44 has penetrated the vaginal introitus.

The fibrous body as referred to in this application can be either a single layer of multiple layers of absorbent fibrous materials as are well-known to those of ordinary skill in the art, such as creped cellulose, airfelt, gauze wadding, etc. When the fibrous body is an airfelt or any other material lacking substantial tensile strength, an overwrap should be placed around either the fibrous body itself or the entire tampon to prevent sloughing off or disintegration of the fibrous body. The fibrous body in this invention is a low density body, i.e., less than about 0.15 grams per cubic centimeter (g/cc) uncompressed and in the range of 0.16 to 0.30 g/cc, and preferably from 0.20 to 0.25 g/cc when compacted in conjunction with a resilient spongiform core in a tubular inserter. The low density textile body is flexible and will provide a better conformability of the tampon to the vaginal walls which it contacts than a highly compressed, high density textile body.

The core can be made of any highly resilient dry expanding material having a relatively low modulus of compression, preferably a spongiform material such as polyurethane foam. It is preferable that the core material also be absorptive to increase the capacity of the tampon. A material which has been found to work well is polyurethane Hydro-Foam available from the Scott Paper Company, Foam Division, Eddystone, Pa. The Hydro-Foam used had a cell count of about 60 cells per inch, was hydrophilic, resilient, dry expanding, and had a low modulus of compression, typically about 0.4 pounds per square inch under the ASTM test D1564, Compression Load Deflection Test (suffix D).

The absorbency of a material like Hydro-Foam can be enhanced by reticulation. A foam such as polyurethane foam is reticulated by opening the common walls between adjacent cells in the foam by methods well-known in the foam art. Reticulation changes closed cell foam to open cell foam and permits fluids to penetrate the foam, thereby enhancing its absorption characteristics.

The dry resiliency of the core material preferably should be greater than about 87 percent. Dry resiliency was determined as follows: A 1 inch .times. 1 inch .times. 1 inch sample was placed on a flat plate which was resting on the compression cell of an Instron Universal Testing Instrument. The sample was placed in such a manner that the height of the sample was 1 inch. The cross head of the Instron having a plate thereon was lowered at a speed of 2 inches per minute and a mark was placed on the Instron chart when the plate initially contacted the top of the sample. The sample was then compressed to 20 percent of its original height (nominally to 0.2 inch) which is 80 percent compression. Immediately upon reaching the 80 percent compression level the cross head started upward to a distance of 11/4 inches above the above mentioned point of initial contact. Upon reaching 11/4 inches the cross head again started down and a mark was placed on the chart at the point where the plate on the cross head again touched the sample. From marks on the chart indicating where the cross head plate contacted the sample, the sample heights; pre- and post- to the compression cycle, were recorded. The percent recovery was determined as the post-compression height divided by the pre-compression height times 100. All samples were tested at 80.degree. F., 30 percent relative humidity. A sample of Hydro-Foam had a pre-compression height of 1.00 inch and a post-compression height of 0.88 inch which was 88 percent recovery.

The core material should have a dry expansion of greater than about 1 percent per minute, preferably greater than about 2 percent per minute, at least for the first 15 minutes. Temporal set occurs while a spongiform material is resiliently compacted within a tubular inserter for extended periods of time. It is classified as temporal because the set dissipates with the passage of time after the tampon is ejected from the inserter. Dry expansion from a temporal set in a spongiform material such as are used in the core of the tampon of this invention has been measured as follows: Samples were prepared from trapezoidal blanks in accordance with the disclosure in the copending, commonly owned U.S. Pat. application, Ser. No. 172,790, entitled HOLLOW FOAM TAMPONS FROM FLAT BLANKS AND METHOD OF MAKING SAME, by Bernard A. Dulle, filed Aug. 18, 1971, incorporated herein by reference. Each blank was 0.4 inch thick, had an altitude of 2.25 inches, a long base of 3.75 inches and a short base of 1.06 inches. Two trapezoidal blanks were coextensively superposed and sewed together along their two common sides and their common short base. The sewed assembly was then turned inside out, i.e., inverted. A string was attached at the apex of the bell-shaped sample to provide a withdrawal string. The samples were resiliently compacted and stored within a tubular inserter having an inside diameter of about 0.71 inch for over 21/2 months. The samples were then placed in vivo, i.e., in female humans, during nonmenstrual times and withdrawn from the vagina after being worn for 15 minutes. Each sample was measured with a scale across the base, i.e., the end opposite the apex, of the sample immediately after withdrawal by the woman who wore the sample. The base of each sample had been measured before it was resiliently compacted and stored in an inserter. The dry expansion was then determined as the pre-compacted base diameter minus the post wearing base diameter times 100. Dry expansion of several samples made from the aforementioned Hydro-Foam polyurethane after 15 minutes in vivo was 15.1 percent and 17.2 percent.

A tampon of this invention in the form of that shown in FIGS. 7 and 8 which has been found to perform well is as follows. A fibrous body was formed from carded rayon fibers. The body was a four-ply web of the carded rayon fibers and was about 1/4 inch thick. Each of the two trapezoids forming the fibrous body had a large base of about 3 inches, a short base of about 3/4 inch, and an altitude of about 21/4 inches. The core 28 was made from the above mentioned Hydro-Foam and was 3/16 inch thick, had a cell count of about 60 cells per inch, had a dry modulus of compression of about 0.4 pounds per square inch, had a resiliency of about 88 percent, and had a dry expansion of about 15 percent in the first 15 minutes. The fibrous body was backed with a layer of fluid pervious material to prevent sloughing off of the rayon fibers from the tampon. This tampon has been found to expand and absorb well.

Thus it is apparent that there has been provided, in accordance with the invention, a tampon that fully satisfies the objects, aims, and advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the appended claims.

Claims

What is claimed is:

1. A tampon, comprising:

a. a flexible, fibrous, absorbent body, said body being in layer form; and

b. a resilient, dry expanding spongiform core;

c. said body being radially compacted about said core;

d. said core being substantially enclosed by said radially compacted body;

e. said body and said core being resiliently compacted so that the density of the body is from 0.16 to 0.30 grams per cubic centimeter;

whereby said body is expanded in a dry condition from a resiliently compacted condition by said resilient, dry expanding core to establish contact with the vaginal walls.

2. The tampon of claim 1 wherein the tampon is a plurality of layers of the body and a plurality of layers of the core, sequential layers of the body being separated by a core layer, whereby the tampon has alternating layers of body and core.

3. The tampon of claim 2 wherein the longitudinal axis of the tampon is substantially normal to and passes through the center of each of the alternating layers.

4. The tampon of claim 3 wherein each succeeding layer of the body is smaller in diameter than the previous layer of the body.

5. A catamenial device, comprising:

a. the tampon of claim 1;

b. constraining means for maintaining the tampon at a predetermined diameter; and

c. release means for removing the tampon from the constraining means;

d. the tampon being resiliently compacted within the constraining means;

whereby the tampon is resiliently compacted to a predetermined diameter to facilitate ease and comfort of insertion into a vagina and dry expands after insertion and release from the constraining means to fill the vaginal cross section before being wetted by menses.

6. The tampon of claim 1 wherein the core is substantially centrally located in the body, whereby the body is omnidirectionally expanded about its longitudinal axis.

7. A tampon, comprising:

a. a flexible, fibrous, absorbent body; and

b. a resilient, dry expanding, spongiform core;

c. said body being radially compacted about said core;

d. said core being substantially enclosed by said radially compacted body;

e. the inside diameter of the body being at least as large as the outside diameter of the core when the body and core are in the uncompacted state;

whereby the body is at least as expansible as the core and the expansion of the core is not restricted by the body.

8. The tampon of claim 7 wherein the core is hydrophilic polyurethane foam.

9. The tampon of claim 8 wherein the core is reticulated, whereby the absorbent capacity of the tampon is increased.

10. The tampon of claim 8 wherein the core has a dry expansion of at least 15 percent in the first 15 minutes.

11. The tampon of claim 7 wherein the body and the core are concentric cones.

12. The tampon of claim 7 wherein the core is a cylinder.