Note: Descriptions are shown in the official language in which they were submitted.
115880S
This invention relates to a tubular knitted diaper in which the
central portion of the diaper comprises on at least one of its
surfaces a pile-looped or terry cloth structure of highly absor-
bent nature, the side portions of the diaper being knitted
integrally with the center portions but in a non-pile type
of stitch.
BACK¢ROUND OF THE INVENTION
In the development of the desirable qualities of absorbency,
softness, and more especially, convenience in use, it has been
common practice to fold woven or knitted diaper fabrics into a
generally rectangular configuration, securing the folded layers
into permanent position by stitching or similar means. Such
diapers ready for application, are commonly called "prefolds",
no matter which particular type of fabric construction they are
composed of.
In the knitted diaper art, it is also known to provide such
diapers with a pile surface, or terry knit, as in U. S. Patent
3955575, to Okuda. Such structures, however, have a pile of
terry knit construction throughout the entire outer surface of
the diaper; further, due to the upper portion of the diaper being
wider than the lower portion, such diapers are not amenable to
rapid, straight-line construction procedures, and are expensive
to produce.
Another type of pile-surfaced diaper is disclosed in U. S. Patent
3367333, to Scheier, introducing the concept of confining the
terry knit yarns to the central portion of the diaper. Such
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diapers, however, are produced by a multi-stage series of
operations involving the formation of a base fabricl the super-
imposition thereon of a set of pile-loop yarns, and a series of
folding and sewing operations to form the fabric into a prefold
diaper.
SUMMARY OF THE INVENTIQN
The present invention relates to a ready-to-use, tubular knit
diaper with at least one central panel of pile or terry knit con-
struction on a least one surface thereof.
The diapers of this invention can be produced more simply,
rapidly, and economically than prior art knitted panel diapers.
The invention will be better understood with reference to the ~:~
following description and drawings, in which:
FIGURE 1 is an isometric view of a preferred embodiment of this
invention in which the pile-knit panel extends lengthwise of the
diaper.
FIGURE 2 is an isometric view of another embodiment of the ~:
invention in which the pile-knit panel extends crosswise of the
shorter dimension of the diaper.
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FIGURES 3, 4, 5, 6, and 7 are representations of cross-sectional
views of five different em~odiments of this invention, as taken
along the line A-A of FIGURE 1 or line B-B of FIGURE 2.
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FIGURE 8 is a magnified representation of a segment of a surface
of a diaper of this invention, showing the pile-knit and non-pile-
knit portions.
Referring now to FIGURE l, the diapers of this invention are of
generally rectangular shape, preferably greater in length than in
width, as indicated at 30. At least one rectangular panel, 25, of
pile-knit construction, comprising hydrophilic yarns, is located
substantially centrally of the diaper, and is bounded along two
of its opposing side dimensions by a pair of non-pile-knit panels
20, 20, which may be of jersey knit or similar stitch. The ground
yarn which forms the jersey stitch may be hydrophilic like the
pile yarn, or may be a hydrophobic yarn such as polyester, thus
adding an element of non-absorbency or dryness to those portions
of the diaper.
All of the diapers of this invention are of tubular knit, which
provides a pair of knitted outside edges, 32, 32, in FIGURE l,
which are soft and conformable, requiring no sewing operations
which are essential for diapers made by folding sheet material.
If desired, the side portions of the pile-knit panel may be
stitched by sewing through both layers of the diaper as at 35, 35
in FIGURE l, or as shown more clearly at 22, 22 in FIGURES 3
through 7. Such sewing serves to anchor the pile-knit panel in
a central portion of the diaper.
The diapers, formed on a circular knitting machine as described
more fully below, are cut to suitable length, the cut edges
being secured as by ~veredge stitching as at 34, 34 in FIGURE l.
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FIGURE 2 is a diaper similar to EIGURE 1 except that the pile-knit
panel runs across the width of the diaper, instead of along its
length. In FIGURE 2, the knitted pile panel 42 is bounded along
its longer dimensions by a pair of non-pile-knit panels 44, 44,
and the knitted edges 46,46 are at the top and bottom edges of
the diaper. The optional sewings 45, 45 along the sides of the
pile panel correspond to the sewings 35,35 of FIGURE 1, and the
overedge stitchings 48, 48 correspond to 34, 34 of FIGURE 1.
As explained more fully below, the diaper of FIGURE 2 is formed on
a circular knitting machine of larger diameter than is employed
for the diaper of FIGURE 1, so that in both cases the pile-knit
panel is created in a continuous and uninterrupted process.
FIGURES 3 through 7 are similar cross-sectional representations
showing five variations of the diapers of this invention. The
diapers, 10, 12, 14, 16, and 18, have in common a tubular knit
construction with a pair of non-pile-knit side panels, 20, 20,
and the optional stitching 22, 22, sewing to stabilize the pile-
knit panel substantially centrally of the diaper.
In FIGURE 3, the pile panel portion 24 is a single panel located
on the interior of one face of the diaper. In FIGURE 4, the pile
panel portion 26 is located on the exterior of one face of the
diaper, which may be accomplished by turning the diaper of
FIGURE 3 inside out before inserting the stitching 22, 22, or,
alternatively, by modifying the circular knitting machine to form
the loops of pile yarn on the outside face of the diaper.
FIGURE 5 is a cross-section of a diaper wherein two pile-knit
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panels, 24, 24, have been formed on both of the inside faces of
the two diaper surfaces as by arranging two sets of terry sinkers
on opposing sides of the circular knitting machine, as will be
readily understood by those skilled in the knitting art.
In FIGURE 6, a pair of pile-knit panel portions have been formed
on both of the exterior faces of the two diaper surfaces, whereas
in FIGURE 7 the two pile-knit panel portions are situated one, 24,
on an interior surface of the diaper and another, 26, on the
exterior of the opposite surface.
In FIGURE 7, two pile-knit panel portions have been formed by
known modification of a circular knitting machine, so that one
portion 26 is formed on the exterior suface of one layer of the
diaper, and a second portion 24 is formed on the interior surface
of the other layer of the diaper.
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FIGURE 8 represents, in magnified form, the transition from a
pile-knît panel area C to a non-pile knit panel area D. A
hydrophilic yarn 54 is interknit with a ground yarn 50, which may
be hydrophilic or hydrophobic. The knitting pattern, governed by
the placement of the sinkers in the circular knitter, is such
that the hydrophilic yarn 54 is formed into pile loops 52 in the
pile-knit panel area, but is knit into a jersey stitch 56,
together with the ground yarn, in the non-pile-knit panel portion.
5PECIFIC EMBODIMENTS OF THE INVENTION
Using a body-size terry-knit machine, such as the Albi Single-
plush Circular Knitting Machine, 12 inch diameter, 18-cut with
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672 needles, the diaper of FIGURE 1, shown in cross-section in
FIGURE 5, was constructed using a ground yarn of 70 denier 34
filament textured polyester (50 ln FIGURE 8) and a loop yarn of
26/1 cotton (54 in FI~GURE 8). Two sections of terry sinkers, 140
in each section, were arranged on opposite sides of the knitting
machine.
The diaper thus produced, with a hydrophilic pile-loop panel on
each of the opposing lnterior faces of the tubular diaper, was
cut into 20 inch lengths and supplied with overedge stitching on
the cut edges. Such diapers, weighing about 50 grams each,
absorbed more than five times their own weight in water when wet
out and subsequently drained for one minute.
The diaper of FIGURE 2 is constructed in similar fashlon except
that the width of the diaper as it comes from the knitting
machine becomes the length of the finished diaper. Therefore a
larger diameter circular knitting machine is used, such as an
Albi of 17 inch diameter, 18 cut, with 960 needles. The opposing
sets of terry sinkers, one on each side of the machine, had 180
sinkers in each section, to provide an eight-lnch terry panel on
each of the opposing interior fa¢es of the diaper. The yarns
employed were the same as in the previous example.
The diaper thus produced comes from the machine in a l9-inch
width, and is cut into 15 inch sections. Overedge stitching is
supplied to the 19 inch edges to provide a finished diaper 19
inches long by 15 inches wide, with the pile panels running across
the width of the diaper.
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OTHER EMBOD~MENTS OF THE I`NVENTION.
Although cotton yarn was specified as the hydrophilic yarn in the
above examples, it is obvious that other hydrophilic yarns may be
employed, such as rayon or hydrophilic synthetic yarns.
It will also be apparent to those skilled in the art that by
adjustment of the sinkers in the circular knitting machine, the
number and placement of the terry panels may be varied from one to
two and may be on the inner or outer surface of the diaper, as
shown schematically in FIGURES 3 through 7. It is similarly
apparent that by the use of a so-called "stripper attachment", as
is used in sock machines, a terry or loop panel can be inserted
at any desired point on the circumference of the knitted article.
Thus, although both a ground yarn and a loop yarn were interknit
throughout the whole circumference of the diapers of the specific
embodiments, above, it is possible to produce the diapers of this
invention by using a single ground yarn and a hydrophilic loop
yarn which is confined to the terry panel or panels.
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