Note: Descriptions are shown in the official language in which they were submitted.
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METHOD FOR CONSTRUCTING A DOUBLE FACE FABRIC
Background Of The Invention
This invention relates to a fabric that has a raised
surface on both faces or sides, and more particularly to a
method for making such fabric by utilizing a double needle
bar warp knitting machine.
It is well known in the fabric field to use a warp
knitting machine in the manufacture of velvet. A three-
dimensional knit fabric is knit on a machine having two
needle beds with multiple guide bars. Two warp knit fabrics
with yarn connecting the two fabrics are formed (see U.S.
Patent No. 3,855,820). After knitting, the fabrics are
split into two pile fabrics by cutting the yarn connecting
them. Each of the two fabrics has a flat warp knit side and
a pile side. The flat side is known as the technical back
and the pile side is known as the technical face of the
fabric (Raz, Dr. S.: "Warp Knitting Production," Verlag
Melliand Textilberichte GmbH, Heidelberg).
Typically, the technical face is brushed to separate
the individual fibers in each yarn bundle and create a face
finished fabric often referred to as velvet. The flat side,
the technical back, is typically not processed and remains
in the as-knit state.
Because only one side of the fabric is face finished,
its use is limited.to applications in which the technical
back is unexposed. As an example, garments made with single
sided face finished fabric with the pile to the outside must
be lined to avoid contact of the harsher technical back with
the wearer's skin.
It is generally understood in the textile community
that double faced fabrics overcome the inherent disadvantag-
es of single faced fabrics for end uses in which both sides
are utilized.
Warp knit fabrics provide inherent technical features.
For example, they can be engineered to have as high a degree
of dimensional stability and durability as woven fabrics,
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properties that are desirable in many end uses and that are
not available in weft knit fabrics. Because the velvet on
the pile side consists of individual fibers of yarn bundles
that are anchored in the warp knit fabric, the velvet is
more resilient than other pile fabrics in which the surface
is raised by simply tearing fibers out of the stitch. This
resilience is maintained, even after repeated laundering,
with the result that the velvet look is maintained and fiber
clumps are not formed. Warp knit fabrics made on double
needle bar machines have the added benefit of providing
enhanced thermal properties by control of fabric thickness
and density. Warp knit fabrics made on tricot machines (see
U.S. Patent No. 4,712,281) can also be face finished on both
sides, but do not provide the range of thermal properties or
resilience possible on double needle bar equipment.
Accordingly, it is desirable to provide fabric which
overcomes the above disadvantages.
Summary Of The Invention
Generally speaking, in accordance with the invention, a
method of constructing a double face fabric is provided.
The first step in the method is to knit a three dimensional
fabric using a conventional double needle bar warp knitting
machine which has a first knit fabric layer, a second knit
fabric layer and a plurality of yarns that interconnect the
two knit layers. Then, the yarns connecting the two layers
are cut, resulting in two pieces of fabric having a pile
surface on one side (the technical face, the side that is
cut), and a flat knit surface on the other (the technical
back). The technical face is brushed to separate the indi-
vidual fibers in each yarn bundle to create a velvet. The
technical back of each fabric is raised by a conventional
process such as napping to form two double face fabrics,
each with a velvet surface on the technical face and a
raised fleece surface on the technical back.
The double face fabric produced by the inventive method
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may be used in a variety of applications, including coats,
sweaters, blazers, blankets, throws and slippers. Either
surface of the fabric may be worn against the skin or under-
garment of the wearer. If the connecting yarn is treated to
be hydrophilic, the velvet side may be worn on the inside
and will wick liquid moisture away from the wearer's skin.
If the connecting yarn is treated to be water repellent, the
velvet side may be worn on the outside to provide the wearer
protection from rain. Alternatively, the double face fabric
may be treated for durable water repellency by a conven-
tional padding operation during finishing, in which event,
either side may be worn on the outside.
Accordingly, it is an object of the invention to pro-
vide a method for preparing a double face fabric.
Another object of the invention is to nap the flat side
of the fabric made on a double needle bar warp knitting
machine in order to form a double face fabric.
A further object of the invention is to provide a
double face fabric for enhancing the transport of moisture
away from the wearer's skin.
Still another object of the invention is to provide a
double face fabric having durable water repellency.
Yet a further object of the invention is to provide a
double face fabric having thermal and insulative properties.
Yet another object of the invention is to provide a
double face fabric having a velvet surface whose appearance
is unaltered even after repeated laundering.
Still other objects and advantages of the invention
will in part be obvious, and will in part be apparent from
the following description.
The invention accordingly comprises the several steps
and the relation of one or more steps with respect to each
of the others, and the material or materials having the fea-
tures, properties, and relation of constituents which are
exemplified in the following detailed disclosure, and the
scope of the invention will be set forth in the claims.
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Brief Description of the Drawings
For a fuller understanding of the invention, reference
is made to the following description in connection with the
attached drawings, in which:
FIG. 1 is a side view showing the loop structure of a
pile fabric produced on a double needle bar warp knitting
machine:
FIG. 2 is a side view in which knitting of a double
needle bar fabric with six guide bars is shown; and
FIG. 3 is a side view in which the splitting of a
double needle bar fabric is shown.
Detailed Description of the Preferred Embodiment
The double face fabric of the invention is prepared by
first knitting a three dimensional knit fabric on a double
needle bar warp knitting machine commonly used in the manu-
facture of single faced velvet and well known in the art.
The three dimensional knit fabric includes a first fabric
layer, a second fabric layer and a plurality of yarn or yarn
elements interconnecting the two layers (Figure 1).
After fabric formation, the fabric may be dyed or
printed, or the yarns that are used for the layers as well
as to connect the layers may be dyed before fabric forma-
tion. The yarns may be either a synthetic material such as
polyester, acrylic, nylon or olefin, and may be spun or
filament (textured or oriented), or natural fibers such as
cotton or wool, or modified natural materials such as rayon
or acetate. The synthetic yarn to connect the layers should
be in the range of 0.3 to 6.0 denier per filament or per
staple if spun yarn is used. The yarn connecting the layers
30. may have been rendered hydrophilic if wicking properties are
required, or it may have been treated to enhance fabric
finishing. The yarn for the layers may be any commercially
available yarn since the layers have virtually no effect on
the performance characteristics of the fabric.
After producing the three dimensional knit, the yarn
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connecting the two surfaces is cut with a splitter (Figures
2 and 3). The result is two single faced fabrics with a
velvet on the technical face and a flat surface on the
technical back.
Thereafter, the technical back of each of the fabric
pieces is raised by a conventional process such as napping,
brushing or sanding. Thus, this surface becomes a fleece
with those attributes and advantages associated with such
fabric.
Preferably, after raising the flat knit surface of each
fabric piece, the raised surface can then be cleaned of
loose fibers by additional brushing or napping and sheared
to even the height therealong. Each resulting fabric piece
thus comprises a velvet fabric surface on one side and a
raised fleece surface that is a non-pilling functional
velour on the other.
It will thus be seen that the objects set forth above,
and those made apparent from the preceding description, are
efficiently attained, and since certain changes may be made
in both the process and products described above without
departing from the spirit and scope of the invention, it is
intended that all matter contained in the above description
shall be interpreted as illustrative and not in a limiting
sense.
It is also to be understood that the following claims
are intended to cover all of the generic and specific fea-
tures of the invention herein described, and all statements
of the scope of the invention which, as a matter of lan-
guage, might be said to fall therebetween.
