Note: Descriptions are shown in the official language in which they were submitted.
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Specification of Patent Invention: "SANITARY NAPKIN"
Background of the invention
The present invention is related to a, preferably disposable, sanitary napkin,
and provided with side wings that can be used initially or during use,
according to the will
and convenience of the user.
As already known in the art, sanitary napkins are normally disposable and
used to collect and contain vaginal exudates, especially menstrual blood,
intermenstrual se-
cretion and even urine in cases of incontinence.
Typically, such napkins are comprised of a generally oblong body made of ab-
sorbent material, wrapped between two layers, one of which is an upper
permeable layer
adapted to contact the user's body, and the other is a lower impermeable layer
facing her
under garment.
The permeable upper layer is adapted to contact the pelvic region of the user,
and therefore it is generally made of a comfortable non-irritating material.
According to the
current state of the art, said layer can be a perforated plastic film, a
porous or crosslinked
foam, a sheet of woven or non-woven material provided with natural fibers
(wood or cotton
fibers), synthetic fibers (polyester or polypropylene), or even of a synthetic
or natural fiber
combination. The upper layer can be of hydrophobic material, thus tending to
remain dry.
On the other hand, the function of the impermeable lower layer is to prevent
the fluid absorbed and retained in the absorbent body from passing through
towards the
user's clothes or skin, and it is generally a fine polyethylene sheet. The
lower layer may be
vapor permeable, in which case it is provided with small pores or made of a
material imper-
meable to liquids.
Prior art sanitary napkins frequently have one or more adhesive regions in the
respective impermeable lower layers, generally in a central portion in the
longitudinal and/or
transverse direction thereof, in order to attach the napkin to the internal
face of the crutch
portion of the user's panties. The adhesive region may comprise a single area
or a series of
discrete areas, and the trend is to apply the adhesive to the lower layer
along one or more
longitudinal bands, to simplify the process of manufacture.
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In its turn, the absorbent body may be made of any material able to absorb
and retain body exudates such as, for example, wood pulp, paper, bamboo
fibers, sugar
cane husks, corn stem or cob, turf moss, absorbent foams or sponges, synthetic
or poly-
meric fibers, super-absorbent materials (that form hidrogels when in contact
with liquids),
combinations of the materials above, and the like.
Currently, most sanitary napkins are provided with fiexible wings that extend
laterally, for example, as a prolongation of one or both of the upper and
lower layers, with
the function of attaching the napkin to the user's panties. For such, the
wings are folded
around the edges of the crotch portion of the panties, and face the external
surface thereof.
Preferably, one or more regions of the wings are coated with adhesives, thus
allowing them
to be attached to the panties for preventing displacement of the napkin when
in use.
The adhesive regions are preferably located over the lower surface of the
wing, which is usually a prolongation of the impermeable lower layer of the
napkin.
The adhesive coated regions, either in the impermeable lower layer of the nap-
kin, or in the respective wings, must be protected against any type of contact
before the
napkin is used, to avoid the risk of losing their adhesive properties or
inadvertent adhesion to
unsuitable parts of the user's napkin or clothes, in which case the napkin
might be damaged
due to the softness of the materials used in its manufacture.
For that purpose, protective sheets are frequently used, which sheets are also
known as "release papers" and are comprised of a sheet of paper coated with
anti-adhesive
resin such as silicone, or the like, thus protecting the adhesive surface
until it is used, at
which time they are removed for exposing the adhesive.
Description of the Art
As to the prior art, reference can be made to U.S. Patent No. 5,281,209
granted to Osborn and Lavash, wherein the wings of a sanitary napkin are
folded and kept
adhered to the lower surface of the napkin body, thus providing a rest
position in which they
will be held in a non-stable state if the user initially does not wish to use
them..
For keeping said wings attached to the body of the napkin when they are not
in use, recessed areas are provided over or inside the impermeable lower layer
of the nap-
kin, under which the wings are temporarily inserted. Such an arrangement
producer a feeling
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of insecurity in the user since the wings could easily get
out of position during use due to the movement of her body
and possibly cause leakage.
U.S. Patent No. 5,330,461 granted to Leeker can
also be cited, this document disclosing a sanitary napkin
provided with optionally usable wings, but the arrangement
prevents the user from pulling the wings out during use, for
part of the surface of the wing acts as a support for the
product as a whole since the beginning of its use.
Mention can also be made of Swedish Patent
SE9601688, granted to Hanssen and Trenk, which discloses a
sanitary napkin provided with optionally usable wings.
However, the option for non-use of the wings implies in the
removal thereof, without possibility of a later use after
the product has already having been put into use.
It is clear that the state of art does not provide
any sanitary napkin having side wings that can be used
optionally by the user even after the product is put to use,
and does not cause discomfort or even leakage if the user
decides not to use them.
Summary of the Invention
One of the main objects of an embodiment of this
invention is to provide a sanitary napkin provided with
wings or tabs that can be used initially or at any time
during use of the napkin.
Another object of an embodiment of the invention
is a sanitary napkin provided with flexible folded side
wings which can be releasably attached before use of the
article.
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Still another object of an embodiment of the
invention is to provide a sanitary napkin having wings that
remain folded during use until the user decides to use them,
thus providing her with a feeling of security from
undesirable leakages.
An aspect of the invention provides a sanitary
napkin which is comprised of an upper liquid permeable
layer; a lower liquid impermeable layer; an absorbent body
placed between the upper and lower layers; an impermeable
top film over the lower layer; laterally extendible foldable
wings that can be lodged in a rest position between the
lower layer and the top film. According to the invention,
the wings are releasably attached at least to the top film.
Another aspect of the invention provides a
sanitary napkin having a length, comprising: an upper liquid
permeable layer; a lower liquid impermeable layer; an
absorbent body between said upper and lower layers; an
impermeable top film over said lower layer, the top film
having opposite longitudinally extending edges; and
laterally extendible wings that can be folded and lodged, in
a rest position, between said lower layer and said top film
in which said wings are releasably attached to said top
film, wherein said top film is provided with longitudinally
extending adhesive bands which are respectively adjacent to
the edges of said top film and which extend along the length
of the sanitary napkin, the bands being suitable for
attaching at least part of the wings to said film, when the
wings are in said rest position, wherein the wings are
comprised of respective adhesive regions and wherein
protective sheets are included over said lower layer and
said sheets are located in such a way that, when the wings
are in the rest position, the respective adhesive regions
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releasably adhere to corresponding ones of said protective
sheets.
A further aspect of the invention provides a
sanitary napkin, comprising: an upper liquid permeable
layer; a lower liquid impermeable layer; an absorbent body
between said upper and lower layers; an impermeable top film
over said lower layer; and laterally extendible wings that
can be folded and lodged, in a rest position, between said
lower layer and said top film; in which said wings are
releasably attached to said top film wherein the top film is
comprised of longitudinal crimped portions suitable for
attaching at least part of the wings to said film when the
wings are in said rest position.
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As used herein, releasable attachment means the existence of suitable
attaching
means (glue, welding, sealing, crimping, and the like) that can be
deliberately undone with-
out significant damage to any of the previously attached underlying
substrates.
An example of releasable attachment is the contact of a permanent touch adhe-
sive (commonly known as "psa", the abbreviation for "pressure sensitive
adhesives") over a
substrate coated with a resin that permits non-permanent adherence.
Still another example of releasable attachment is that attained by crimping,
which
consists of pressing two or more layers of material against each other, in
such a way that the
interface between the two layers can provide a surface with protuberances and
recesses for
the inter-penetration between the respective materials, thus releasably
attaching one layer to
another.
Brief Description of the Drawings
The present invention will be described below in greater details with
reference
to the accompanying drawings that represent non-limiting alternative
embodiments, wherein:
Figure 1 is a top view of a sanitary napkin that represents a first preferred
embodiment of the present invention;
Figure 1A is a cross-sectional view of Figure 1, taken along line AA;
Figure 2 is a top view of a sanitary napkin that represents a second preferred
embodiment of the present invention;
Figure 3 is a top view of a sanitary napkin that represents a third preferred
embodiment of the present invention; and
Figure 4 is a top view of a sanitary napkin that represents a fourth preferred
embodiment of the invention.
The left side of the figures show the situation in which the side wing is re-
leasably attached to the sanitary napkin prior to use thereof, and the right
side shows the
situation in which the side wing has been dislodged from the rest position and
is ready for
use.
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Detaifed Description of the Figures
As illustrated in Figures 1 to 4, sanitary napkinl comprises a substantially
planar
absorbent body 2 surrounded by a permeable upper layer 4 suited to contact the
user's body
and by an impermeable layer 5 facing the user's underclothes.
As known in the art, napkin 1 is also has flexible wings 10 that extends
laterally
as a prolongation of upper and lower layers 4 and 5, respectively. The lower
face of each
wing 10 is provided with a first adhesive region 11, allowing its attachment
to the crotch por-
tion of the user's panties, thus configuring an in-use position for the wings.
At least one impermeable top film 13 is provided, which extends longitudinally
along at least part of lower layer 5. Film 13 is attached to lower layer 5
along lines 6 in such
a way that it covers the ends of wings 10 when these are folded, thus
configuring a corre-
sponding rest position. A second adhesive region 12 can be provided in at
least a longitudi-
nal portion of film 13, being protected by a resin-coated protection sheet 3.
In accordance with a first preferred embodiment of this invention, as
illustrated in
Figure 1, longitudinal adhesive bands 20 are provided, which bands are
respectively adja-
cent to the edges of film 13. Each one of bands 20 provides for a releasable
attachment of
relevant wing 10 to film 13.
Bands 20 must be provided with length and width suitable to keep wing 10
steady. Thus, the length of said band 20 may vary, covering a longitudinal
portion that may
be shorter, equal or even longer than the portion for contact between said
wing 10 and layer
13. Preferably, band 20 covers all the extension of contact between said wing
10 and layer
13 of napkin 1.
Sheets 16 for protecting adhesives 11 on lower layer 5 are also provided,
which
sheets are positioned in such a way that, when wings 10 are resting, the
corresponding ad-
hesive regions 11 releasably adhere to corresponding protective sheets 16. The
use of said
protection sheets 16 allows a partial adhesion of adhesive regions 11 to lower
layer 5, in
such a way that they do not lose its adhesive capacity when wings 10 are
removed from
their rest position.
Napkin 1 may also comprise additional protective sheets (not shown) between
wings 10 and respective bands 20, the rest of each band 20 attaching film 13
to lower layer
5.
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As illustrated in Figures 1 through 4, extensions 14 in the ends of wings 10
are
provided so that the user can pull them out when using the sanitary napkin 1,
said wings 10
then being available for being attached to the crotch portion of the outer
face of the user's
panties.
In accordance with a second embodiment of the present invention, illustrated
in
Figure 2, the attachment of wings 10 between lower layer 5 and top film 13 is
accomplished
by a crimping process, thus replacing adhesive band 20 with a crimping portion
30.
As shown, crimped portions 30 extend along the longitudinal edges of film 13,
and they can have the same length as napkin 1.
As previously described, the user will have to pull extensions 14 whenever she
wants to use wings 10 of napkin 1, thus releasing the crimped portion 30 that
holds wings 10
in the rest position and freeing them for use.
In accordance with a third preferred embodiment of this invention, illustrated
in
Figure 3, weakening lines 40 are provided, preferably as weakened or punched
lines, in film
13, such lines delimiting detachable portions 45 of film 13 itself. Such
detachable portions 45
are respectively attached in a non-detachable manner to wings 10 in their rest
position. In
this way, when the user pulls extensions 14, weakening lines 40 are broken,
thus freeing
wings 10 for use.
In accordance with a fourth embodiment of this invention, illustrated in
Figure 4,
and maintaining a certain similarity with the first embodiment shown in Figure
1, film 13 is
shorter than the length of napkin 1. A band of glue, not shown, extends over
lower layer 5 of
napkin 1, going from a longitudinal end to the opposite one, except between
lines 6, where
said glue band covers the outer surface of film 13. Lines 6 are lines for
attaching film 13 onto
lower layer 5.
Various examples of preferred embodiments having been described, it is to be
understood that the scope of the present invention encompasses other possible
variations, it
being limited only by the content of the accompanying claims, wherein possible
equivalents
are included.
