U.S. patent number 3,805,790 [Application Number 05/252,599] was granted by the patent office on 1974-04-23 for preshaped feminine napkin.
This patent grant is currently assigned to Kimberly-Clark Corporation. Invention is credited to Leonard M. Kaczmarzyk, Robert F. Skora.
United States Patent |
3,805,790 |
Kaczmarzyk , et al. |
April 23, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
PRESHAPED FEMININE NAPKIN
Abstract
A feminine napkin of predetermined shape, dimensioned to conform
particularly well to the perineal area of the female body over a
wide range of anatomical sizes. The defined shape and dimensions
enables the napkin to automatically position itself properly with
respect to the body when worn while at the same time providing
improved comfort. In addition, the napkin is substantially
non-discernible to the casual observer, even when worn in
combination with tight-fitting garments. The napkin is also adapted
for adhesive attachment to supporting garments.
Inventors: |
Kaczmarzyk; Leonard M. (Neenah,
WI), Skora; Robert F. (Neenah, WI) |
Assignee: |
Kimberly-Clark Corporation
(Neenah, WI)
|
Family
ID: |
22956699 |
Appl.
No.: |
05/252,599 |
Filed: |
May 12, 1972 |
Current U.S.
Class: |
604/369; D24/125;
604/370; 604/377; 604/378; 604/387 |
Current CPC
Class: |
A61F
13/47245 (20130101); A61F 13/51305 (20130101); A61F
13/512 (20130101); A61F 13/47272 (20130101); A61F
2013/53782 (20130101); A61F 2013/582 (20130101); A61F
13/537 (20130101); A61F 2013/51409 (20130101); A61F
13/58 (20130101); A61F 2013/51186 (20130101) |
Current International
Class: |
A61F
13/15 (20060101); A61F 13/56 (20060101); A61f
013/16 () |
Field of
Search: |
;128/284,285,286,287,290,296 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Rosenbaum; Charles F.
Attorney, Agent or Firm: Hanlon, Jr.; Daniel J. Herrick;
William D. Miller; Raymond J.
Claims
What is claimed is:
1. An anatomy-conforming feminine napkin of predetermined shape and
comprising a preshaped absorbent pad member, a fluid-pervious cover
member, and a preformed fluid-impervious backing member; said
preshaped pad member when viewed in plan comprising an elongate
generally biconcave pad having a major and a minor axis, the sides
of said pad flanking said major axis being generally and
symmetrically concave, and said minor axis being disposed
perpendicular to said major axis at the narrowest point of
biconcavity; the dimension of said minor axis being in the range of
about 1 1/4 inches to about 1 3/4 inches; said concave sides being
defined by a curve the segments of which have a radius of curvature
of no less than 2 inches and no more than 4 inches, said curve
being perpendicular to said minor axis at its intersection
therewith, and the length of the chord which subtends said curve
being from about 2 1/2 inches to 5 inches; said impervious backing
member comprising a preformed shallow basin into which said
preshaped pad member is nested; the fluid pervious cover member
being of the same contoured outline in plan view as said pad member
to overlie the entire top surface of said pad member; said cover
member being substantially planar; the peripheral edges of said
cover member extending slightly beyond the edges of said pad member
and being secured to the top periphery of the walls defining the
shallow basin formed by said backing member.
2. The feminine napkin of claim 1 wherein said concave curve is the
arc of a circle.
3. The feminine napkin of claim 1 wherein said concave curve is
elliptical.
4. The feminine napkin of claim 1 wherein the end portions of said
pad member disposed on either side of said minor axis are of
unequal width and length, the narrower and shorter of said end
portions defining the rear end of the pad as worn, and wherein said
pad member is thickest at said minor axis tapering to thinner
portions at each end, being feathered at one end while being about
one-half of the minor axis thickness at the other end, said latter
end being the rear of said pad as worn, and said feathered end
being the front of said pad as worn.
5. The feminine napkin of claim 1 wherein said cover member
comprises a non-woven web of hydrophobic fibers.
6. The feminine napkin of claim 5 wherein said cover member is
provided with spaced perforations.
7. The feminine napkin of claim 1 wherein said preformed fluid
impervious backing member comprises a thin plastic film.
8. The feminine napkin of claim 1 wherein said preformed fluid
impervious backing member comprises a thin plastic foam.
9. The feminine napkin of claim 8 wherein at least the bottom
surface of said foam is a closed skin.
10. The feminine napkin of claim 1 wherein said napkin is adapted
to be removably attached to a supporting garment by having pressure
sensitive adhesive means disposed on said fluid-impervious backing
member.
Description
BACKGROUND OF THE INVENTION
Feminine napkins presently used for catamenial protection comprise
absorbent pad structures which for the most part are of elongate
and substantially rectangular configuration. The market is provided
with a large variety of such napkins in different lengths, widths,
and thicknesses, each of which is designated as being suitable for
a particular body size or shape, for heavy or light flows, or for
different age needs. In addition to the more common rectangular
form, there exists a limited selection of other geometric
configurations also designed to meet particular body shapes or
sizes.
As the result of an extensive anatomical study of the perineal area
of subjects who fall in the various size groups it has now been
found, rather surprisingly, that the dimensions of the female body
in the area where catamenial protection devices are worn does not
vary as much between groups as had been suspected. As a result it
has been found possible to design an anatomy-conforming absorbent
pad which, within certain critical dimensions, provides
satisfactory absorptive protection for practically all body shapes
and sizes. In addition, the improved pad was found to provide
decreased bulk, and improved comfort and secrecy when worn, as
compared to more conventional pads. The present invention is
directed to an improved feminine napkin structure which provides
the desirable characteristics enumerated above.
SUMMARY OF THE INVENTION
The improved feminine napkin of this invention comprises an
absorbent pad of a predetermined, anatomy-conforming shape adapted
to be removably attached to a supporting garment by adhesive means.
The napkin is made of conventional materials, i.e., a highly
absorbent core of fibrous material or the like, a fluid-pervious
cover member, and a fluid-impervious pre-shaped backing member,
preferably of thin plastic film, with pressure sensitive attachment
means disposed thereon. The invention lies primarily in the
anatomy-conforming shape of the pad and backing member, as well as
the manner in which the component members are assembled. The shape
of the anatomy-conforming pad when viewed in plan comprises an
elongate, biconcave pad body in which the biconcavity lies along
its major axis. The minor axis of the pad lies perpendicular to the
major axis at the narrowest point of mutual concavity. The
dimension of the minor axis and the concave curvature of the side
edges are critical. The minor axis dimension is preferably 1/2, but
may fall in the range of about 1 1/4 to about 1 3/4.
The dimensions of the curvature which provide the concavity of the
pad body are also critical. These latter dimensions may be variable
within a certain range but can be specifically defined in
mathematical terms. A preferred shape for each of the concave arcs
making up the side edges of the pad is a circular arc of about 3
1/4 radius, but may fall within a range of about 2 to 4. A
preferred length of the chord which subtends the circular arc of
the preferred radius is about 3 3/4, but may have a length of from
about 2 1/2 to 5. Variations of these parameters within a range
specified are permitted as further specified in the detailed
description.
The length of the napkin is not critical, but preferably is from
about 6 to 8. Larger sizes are not needed for the majority of users
because, if larger, the utilization of the available absorbent
capacity is grossly inefficient and is therefore wasteful and
uneconomical. A pad dimensioned as described will automatically
seat itself over the perineal area within the inner curvature of
the wearer's thighs.
The ends of the pad body may be generally parallel and of equal
width while being equally spaced from the minor axis. In the
preferred form, the rear end portion of the pad is shorter and
narrower than the front end portion. The pad is preferably thickest
in section at the minor axis, and is tapered down toward each end.
In the preferred form, the thickness of the rear end portion tapers
less than the front end portion, and retains substantial thickness
for improved absorption in that area.
In another important structural feature, the fluid-impervious
backing member comprises a preformed shallow basin into which the
preshaped pad body is snugly nested. The peripheral walls of the
shallow basin thus are in contact with and extend around, the
entire outer periphery of the pad body to provide an impervious
fluid-holding container. The fluid-pervious cover member is of the
same contour in plan view as the pad body to overlie the entire top
surface of the pad body. The peripheral edges of the cover member
are secured to the top edge of the backing member wall around the
entire periphery thereof. The bottom face of the impervious backing
member may have pressure sensitive adhesive means applied thereto
and is covered by a protective strip. When this strip is removed,
the adhesive serves as the means to attach the napkin to a suitable
supporting garment.
Other features, objects and advantages will become apparent by
reference to the detailed description and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective top view partly in section of a feminine
napkin in accordance with one embodiment of the invention.
FIG. 2 is a plan view of a feminine napkin generally similar to the
FIG. 1 embodiment.
FIG. 3 is a longitudinal section taken at line 3--3 of FIG. 2.
FIG. 4 is a bottom view of a feminine napkin in accordance with the
FIG. 1 embodiment.
FIG. 5 is a perspective top view partly in section, and generally
similar to FIG. 1, of another embodiment of the feminine napkin of
the invention.
FIG. 6 schematically illustrates in plan the critical dimensions of
a feminine napkin in accordance with the invention.
FIG. 7 schematically illustrates the parameters of the curves
defining the concave sides of the napkin.
DETAILED DESCRIPTION OF THE INVENTION
In the preferred embodiments of the invention as shown in the
accompanying drawings reference is made first to FIGS. 1-4 wherein
there is shown an elongate feminine napkin 10 with symmetrically
concave side edges 12 and 14. The biconcave napkin 10 is comprised
of an absorbent pad body 16, enclosed within a preformed
fluid-impervious backing member or baffle 18 which is formed into
the shape of a shallow continuous-walled basin, and covered by a
fluid pervious cover member 20.
Cover member 20, in plan view, is of the same biconcave contour as
absorbent pad body 16. As shown, the edges of cover member 20
extend slightly beyond the entire periphery of pad body 16 and are
secured to backing member 18 along the entire periphery of the
backing member walls as indicated at 22.
In a preferred embodiment, feminine napkin 10 may have located on
the bottom of backing member 18 a strip of pressure sensitive
adhesive 24, or the like, covered by a protective release sheet 26.
Sheet 26 may be removed to expose adhesive 24 for attachment to a
suitable supporting garment. In instances where a tight-fitting
undergarment is worn, of course, there is no need for the adhesive,
since the close fit of the garment itself will hold the napkin
tightly against the body, while the anatomical shape of the napkin,
as shown, will be sufficient to maintain the preshaped feminine
napkin in proper position longitudinally with respect to the
perineal area.
As indicated earlier, the elements which make up feminine napkin 10
may consist of known conventional materials. Pervious cover member
20 may consist of a non-woven thread web, a bonded carded web of
absorbent of non-absorbent staple fibers, or an autogeneously or
otherwise bonded web of continuous filament synthetic fibers. Many
variations of such materials are well known in the art. A preferred
cover material is comprised of a hydrophobic, but fluid-permeable,
autogeneously bonded web which, due to its hydrophobicity and
one-way permeability when in contact with an absorbent pad body,
helps provide the napkin with a desirable dry-feeling surface when
in use. One embodiment of a preferred cover material is illustrated
in FIG. 2 at 20a. As shown there, it is provided with a
multiplicity of spaced perforations 21 to aid in rapid fluid
penetration by menstrual exudate.
Absorbent pad body 16 may comprise natural absorbent cellulosic
fibers such as wood pulp fluff, cotton, cotton linters,
multi-layered cellulose wadding, or combinations thereof. It may
also include regenerated cellulose fibers or sponge, staple rayon
fibers, and various mixtures of absorbency-aiding materials, such
as natural or synthetic gums, modified cellulose materials and the
like.
While the absorbent pad body 16 may be of substantially uniform
thickness throughout, it has been found that more efficient use per
unit weight of the absorbent capacity is obtained by strategically
locating the bulk of the absorbent material at the center and near
the rear end portion of the pad. A preferred embodiment of such an
arrangement is illustrated in the longitudinal section of FIG. 3.
As noted by reference to that figure, the pad body is thickest in
area 16 which is coincident with the transverse minor axis of the
pad body. The absorbent material tapers down to about one-half this
thickness at the rear end of the pad designated 17, and tapers down
to a feathered edge at the front end of the pad 19. Most of the
fluid absorbed in use is retained in the central and rear end
portions of the pad. The feathered front end serves to preserve
secrecy because of its inconspicuity when worn.
Fluid impervious backing member 18 is preferably a thin plastic
film such as polyethylene or polypropylene of about 1/2 to 3 mils
in thickness. Other thin flexible films such as polyvinyl chloride,
polyvinylidene chloride, natural rubber, etc. may be employed.
Another useful material is a thin polyurethane foam which may be of
open or close-celled construction on the interior, and may be
absorbent or nonabsorbent, but which should have a closed
fluid-impervious skin or at least the bottom surface. An
illustration of one embodiment of such foam is shown at 28 in FIG.
5.
As indicated in the summary of the invention, the
anatomy-conforming shape of the feminine napkin and several of its
key dimensions are particularly critical. FIGS. 6 and 7
schematically illustrate these dimensions.
The typical profile of a feminine napkin in accordance with this
invention as represented by FIG. 6, has a rear end portion 31 and a
front end portion 32. Line A--A is drawn through the longitudinal
or major axis of the pad body. Line B--B is disposed at the
narrowest point of biconcavity perpendicular to line A--A, and is
drawn through the transverse or minor axis of the pad body. The
dimension C on minor axis Line B--B indicates the narrowest area of
biconcavity, and should have a dimension in the range of from 1 1/4
to 1 3/4, with 1 1/2 being preferred.
The preferred parameters for the curvature of the concave edges of
the pad will now be described with reference to FIGS. 6 and 7.
The pad edges may be described as being minor-symmetrical about the
major axis A--A. That is, given the shape of the pad edge on one
side of the axis, the shape of the other pad edge may be obtained
by folding or reflection about axis A--A. With this in mind, it
will be sufficient to specify the edge of the pad on one side of
A--A.
The critical area for the shape of the concave curvature lies
between lines D--D and E--E. Line D--D is shown as being spaced
distance a forward of minor axis B--B, and line E--E is shown as
being spaced distance b rearward of B--B. The sum a+b also defines
the length of the chord of the arc segment for the concave edge
lying between D--D and E--E. Distances a and b are preferably each
1 7/8 in. However, the sum of a+b may range from 2 1/2 in. to 5
in.
Within this range, the preferred shape for the pad edge H--H (see
FIG. 7) is a circular arc of radius 3 1/4in. It is noted that the
reflected arc for H--H, G--G and F--F in FIG. 7 are indicated by a
"prime" symbol. The center of curvature in this figure is of course
fixed on axis B--B, at a distance 3 1/4 in. outward from the pad
edge.
However, the inner aspect of the female thigh adjacent the perineal
body is not a perfect arc, but an irregular curve which changes
with body attitude and movement. Accordingly, it has been found
that the concave edge H--H of FIG. 7 may be satisfactorily
described by any smooth curve, always concave outward, whose radius
of curvature is between 2 in. and 4 in. at every significant
segment of the curve and which is perpendicular to the minor axis
B--B at its intersection with B--B. Thus the center of curvature
may shift as one moves along the curve. Where the curve intersects
B--B, the center of curvature must lie on B--B, in order to make
the curve perpendicular to B--B at that point; elsewhere on the
curve, the center of curvature may shift continuously but smoothly,
so that both the curve and its shape are continuous.
Thus, for example, a half-ellipse of major diameter 6.35 in., minor
diameter 5.04 in., halved along its minor diameter and placed with
its major diameter along B--B, would satisfy the criteria for the
case where a and b are each less than 2.52 in. At its intersection
with B--B, the ellipse would have its sharpest curvature with a
radius of (2.52).sup.2 /3.175, or 2.0 in. The curvature of the
ellipse gradually decreases as one moves away from B--B, but at the
farthest conceivable reach, a distance 2.52 in. from B--B, the
radius of curvature is (3.175).sup.2 /2.52 or 4.0 in.
The boundaries of all allowable curves will be the circular arc of
radius 2 in., shown as F--F in FIG. 7, and the circular arc of
radius 4 in., shown as G--G. The allowable curves, while not
necessarily circles themselves, cannot turn outward any more
rapidly than F--F nor any more slowly than G--G, since their radius
at every point are between these limits.
It may be noted that these limits also prohibit any straight-line
segments (radius of inifinity) and any sharp corners (radius =
0).
It is understood that C which defines the minor axis of the pad may
have a dimension in the range of from about 1 1/4 inches to 1 3/4
inches and that the explanation of the relative curvature applies
to any crotch structure within these preferred dimensions.
When various feminine napkins constructed within the ranges of the
above-defined dimensions were tested in use, they were found to
provide a desirable indexing function. That is, because the concave
dimensions and narrow pad width at the minor axis conform so
closely to average body measurements, when the pad is worn the
narrow portion and associated curvature automatically maintain the
pad in a properly indexed position with respect to the longitudinal
axis, through all normal body movements.
In this respect, the feminine napkin, as described herein was found
by the subjects who tested the pads to be superior in comfort and
placement, when compared with the conventionally shaped pads
described in the background section of this specification.
It was also found that because conventionally shaped pads tend to
form longitudinal folds and to bunch together transversely when in
contact with the narrow crotch area of the body, they were a source
of some discomfort and early leakage. The latter characteristics
were judged by subjects who tested various types of napkins to be
minimized by the improved napkins described herein.
Another undesirable characteristic of conventionally shaped pads is
the tendency for such pads to move forward or backward while being
worn. As indicated above, this type of movement is largely overcome
by the automatic indexing or positioning characteristics of the
anatomically shaped napkin of the present invention.
* * * * *