Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02721464 2010-11-17
19748P0001CA02
A Touch Fastening Anti-Skidding Material and Method of Making the Same
(a) Technical Field of the Invention
The present invention relates to a novel design of knitted structure of a
touch-fastening
anti-skidding fabric, which has the features of being fit for mass production
and manufacture of large
width surface area fabrics that have flexibility, resiliency, and light
weight, and also offers the
advantages of high air permeability and low manufacturing costs, and is fit
for combination with other
materials and suitable for being bonded to various felts, rugs, flannelette,
loop cloth (terrycloth) to
realize touch-fastening and anti-skidding.
(b) Description of the Prior Art
The commonly known hook-and-loop types of touch-'!fastener straps is Velcro
straps (Velcro is a
Registered Trade Mark of Velcro Industries BV) and these have the features of
touch-fastening and
anti-skidding. The known hook-and-loop straps are often composed of a first
band that has a plurality
of male hooks and a second band that has a plurality of female loops that are
engaged by the male
hooks when the two bands are placed into mutual contact. The male hook band
has a surface
forming a felt-like face on which a plurality of projecting hooks that have
ends forming hooks is
uniformly distributed. The female loop band has a surface forming a velvet-
like face on which curled
and entangling yarns are uniformly distributed. When the felt-like faces of
the male and female
bands are put together so as to mutually confronts and touches each other, the
hooks engage the curled
and entangling yams so as to hold the bands together. The known structure of
the touch-fastener
strap is effective in fixing articles to be fastened together, but the
conventional touch-fastener strap
suffers high manufacturing costs and difficulty in making large width
products, and is only fit for
continuous manufacture of small-surface-area elongate straps, making the
production performance
very poor. Further, the conventional touch-fastener strap is generally not
pliable, making it difficult
to bond to articles or materials showing a three-dimensional shape.
1
CA 02721464 2011-07-12
We are aware of British patents GB 927828, GB 1193130, GB 1289825, and
GB2049749, Erunpean
Publication EP1698245A3, US Patent US4854136 and Japanese Publication JP
20040415 all of which describe
various hook-and-loop type oftouch fastening fabrics but none of these
disclose a textile warp knitted fabric in which
the synthetic threads form the hooks are knitted together along the wales of
the fabric. Furthermore none of these
disclose the concept of knitting with pliable textile yams and synthetic
filaments that have totally different
charac eristics to the pliable threads together to form a foundation layer.
In the patent application there is described and shown in the drawings a
unique touch-fastening material, which
is manufactured by knitting synthetic fibres with pliable yams of different
char teristics or different diameter sizes in
order to suit the needs of different applications, wherein the length of the
synthetic fibres used to form the male hooks
can be set according to the kitting method used. The present application
describes in more detail the method of
manufacturing the fabric.
SUMMARY OFTHE INVF NTION
An object of present invention is to provide a mauve, lightweight, airmneable,
resiliently
expandable, and stnrcture simplified anti-skidding fabric that provides
effective skidding resistance for use with
various other materials, including felts, rugs, flannelette, and loop cloth
(texrycloth) that have a looped or entangling
stmetures to form atouch fastener.
An object of the present invention is to provide a stnic ure of touch-
fastening anti-skidding fabric formed by
warp knitting whereby the fabric is flexible and resilient, and which is
formed by knitting pliable yams simultaneously
with synthetic filaments or fibres that form the legs and have different
characteristics to those of the pliable yarns, so
that a knitted foundation layer is formed that comprises a great number of
synthetic fibres projecting therefrom that are
used to form hooks.
2
CA 02721464 2010-11-17
A further object is to provide a touch fastening fabric that can be
manufactured in a mass
production manner with excellent features of light-weight, air permeability,
resilience, and
processability.
Another object of the present invention is to provide an anti-skidding fabric,
which possesses
excellent stretchability and flexibility that offers excellent characteristics
of being easily applied to a
three-dimensional surface so that the anti-skidding material can be easily
shaped for forming an
excellent bonding surface for three-dimensional configuration.
A further objective of the present invention is to provide a touch-fastening
anti-skidding material
that can be used with felts, rugs, flannelette, and loop cloth (terrycloth)
for anti-skidding purposes.
According to one aspect of the present invention there is provided a touch-
fastening anti-skidding
warp knitted fabric comprising a foundation layer that has wales of the fabric
that comprise pliable
base yams and a plurality of discrete synthetic filaments knitted together,
wherein each stitch of the
synthetic filaments is looped around a previous stitch of the filament in the
same wale and is
subsequently cut to form a discrete length of the filament that comprises a
loop in the foundation layer
and two legs projecting from the foundation layer..
Preferably the synthetic fibres are monofilaments selected from the following
synthetic materials
polyamides, polyesters, polypropylene, and polyethylene. Preferably the
synthetic filaments each have
a diameter in the range of 0.02mm to 0.5mm and have a Shore hardness of
between 35A to 90A or
between 40D to 90D.
Preferably the pliable yams are natural or synthetic spun yams selected from
the group
comprising acrylic, cotton, cellulose, or polyester cotton, or blends of these
fibres.
Preferably the pliable yams and the synthetic filaments are knitted so that
each stitch of synthetic
filament is looped around a previous stitch of the synthetic filament along
the wales of the fabric to
3
CA 02721464 2010-11-17
form a wale of loops of synthetic filaments, and the pliable yams accompany
the stitches of the
synthetic yams to form the loops that are extended transversely to an adjacent
wale of the fabric.
The foundation layer of the fabric may have apertures and the apertures the
shape of the
apertures is selected from the following shapes namely, polygonal, circular,
hexagonal, rectangular, or
quadrangular. Alternatively the foundation layer need not have apertures
knitted into its structure.
According to a further aspect of the invention there is provided a method of
warp knitting a touch
fastening fabric having hooks for engaging loops or entangling structure of
another structure, wherein
the method comprising the steps of:-
(a) Simultaneously warp knitting a plurality of continuous lengths of pliable
yams
together with a plurality of continuous lengths of synthetic monofilaments on
a double
needle bed warp knitting machine to form two foundation layers each of which
is knitted on
one of the needle beds and has wales of the fabric that have the stitches of
the synthetic
filament linked together along the wale with wales of the foundation layers
linked along and
between the wales by the pliable yams, and wherein the two foundation layers
are linked
together by stitches of the synthetic filaments that extend between the two
foundation layers;
and
(b) Cutting the stitches of the synthetic filaments that extend between the
foundation layers to form two separate fabrics each of which has a foundation
layer with
discrete lengths of the filaments that have a loop linked to the next stitch
of the filament
along each wale of the foundation layer and two legs projecting from the
foundation layer.
Preferably the knitting process is commenced by knitting pairs of adjacent
wales together with
the pliable yam passing from one wale to the next of the wales of the pair.
Preferably the foundation layer comprises wales that are knitted by passing
the pliable yams
between adjacent wales of the foundation layer.
4
CA 02721464 2010-11-17
Apertures may be formed in the foundation layer by knitting a set of first
pairs of wales, splitting
each of the first pairs of wales into two wales and passing the pliable yarns
to an adjacent one of the
wales of each split first pair of wales and knitting the wales together to
form a second set of pairs of
wales, splitting the second pairs of wales into two wales and passing the
pliable yams to an adjacent
one of the wales of each split second pair of wales and knitting the wales
together to re form the set of
first pairs of wales and thereby define apertures in the foundation layer
between the wales.
The present invention provides a touch-fastening anti-skidding material, which
comprises a
knitted foundation layer and a plurality of synthetic fibres or yams that is
collectively knitted in the
foundation layer and secured together. The synthetic filaments possess
predetermined rigidity strength
to provide strong legs that project from the foundation layer whilst the
pliable yams make a
foundation layer that is flexible, resilient, and light-weighted. Together the
contrasting characteristics
of the filaments and yarns produce a fabric that when placed in contact with
felts, rugs, flannelette, and
loop cloth (tenycloth), the anti-skidding material of the present invention
provides excellent resistance
against skidding.
The foregoing objectives and summary provide only a brief introduction to the
present invention.
To appreciate fully these and other objects of the present invention as well
as the invention itself, all of
which will become apparent to those skilled in the art, the following detailed
description of the
invention and the claims should be read in conjunction with the accompanying
drawings.
Throughout the specification and drawings identical reference numerals refer
to identical or similar
parts.
Many other advantages and features of the present invention will become
manifest to
those versed in the art upon making reference to the detailed description and
the accompanying sheets
of drawings in which a preferred structural embodiment incorporating the
principles of the present
invention is shown by way of illustrative examples.
5
CA 02721464 2010-11-17
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a touch-fastening warp knitted fabric that has a network of
apertures X and is
constructed in accordance with the present invention;
Figure 2 shows a second touch-fastening warp knitted fabric that does not have
the network of
apertures X like those of the fabric of Figure 1 and is constructed in
accordance with the present
invention;
Figures 3 and 4 show, schematically, the steps of the knitting part of the
fabrics of Figures 1 and
2;
Figure 5 shows schematically a cross sectional view taken along one of the
wales of the fabric
shown in Figures 3 and 4;
Figure 6 shows schematically steps of knitting the apertures in the fabric of
Figure 1;
Figures 7 and 8 show in greater detail a portion of the knitting shown in
Figure 6;
Figure 9 is a schematic view showing legs of the fabric of Figure 1 or Figure
2 that has been
subjected to heating to melt the tips of the legs to form hooks; and
Figure 10 is a schematic view showing legs of fabrics of Figures 1 or 2 that
have been subjected
to heating and deformation to form hooks.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following descriptions are exemplary embodiments only, and are not
intended to limit the
scope, applicability, or configuration of the invention in any way. Rather,
the following description
provides a convenient illustration for implementing exemplary embodiments of
the invention.
Various changes to the described embodiments may be made in the function and
arrangement of the
elements described without departing from the scope of the invention as set
forth in the appended
claims.
6
CA 02721464 2010-11-17
Referring to Figures 1 and 2 the fabrics 10 and I0a each comprise a foundation
layer 40 that has a
plurality of hooks 22 projecting from the plane of the foundation layer 40. In
use, when the fabrics 10
or I Oa are brought into contact with another fabric or surface (not shown)
that has a looped or tangled
structure, such as for example, felts, rugs, flannelette, and looped cloth
(terry-cloth), the hooks 22
engage and tangle with the other fabric or surface to grip it and thereby
create a touch fastener that can
be pulled apart.
The difference between the fabric of Figure 1 compared with the fabric of
Figure 2 is that the
knitted foundation layer of the fabric of Figure 1 has network of apertures
"X" formed during the
knitting process, whereas the fabric of Figure 2 does not
For simplicity, in the following description of Figures 3 to 10 of the
drawings, only a few wales
or columns that extend along the length of the fabrics 10 or I Oa are shown.
These wales are identified
by the references "A" and "B". It is to be understood that the pattern of
stitches shown in the drawings
is repeated throughout the width and length of the fabrics 10 and 10a, thus
permitting fabrics of
various widths and stretchability to be made.
Both of the fabrics of Figures 1 and 2 are warp knitted on a double needle bed
warp knitting
machine in which two foundation layers 40 are knitted simultaneously (one
layer 40 on each needle
bed) as a single structure with the stitches 20a and 20b knitted across the
two needle beds. Once the
knitted structure is removed from the needle beds of the knitting machine the
stitches 20a and 20b that
extend between the foundation layers 40 are then cut to separate the
foundation layers 40 and form
two identical fabrics 10, or I Oa as shown respectively in Figure 1 or Figure
2 whilst at the same time
the legs 22 of the cut stitches are used to form the hooks of the fabric. By
varying the tension of the
stitches 20 and 20b across the needle beds it is possible to make longer or
shorter legs 22.
To make the double knitted structure that is cut to form two fabrics 10 or I
Oa of the present
invention, continuous lengths of two types of textile yams or filaments are
knitted simultaneously. The
7
CA 02721464 2010-11-17
two types of filaments and yams used are fibres 20a and 20b that form the legs
22 that are used to
make "hooks" of the fabric 10, and pliable fibres 30a and 30b that form each
the foundation layers 40
of the fabric 10 and hold the legs 22 into place in the foundation layer 40.
The fibres 20a and 20b are preferably monofilaments (sometimes called "Drawn
Textile Yarns
(DTY) or extruded filaments) selected from one or more of the following
synthetic plastic materials,
namely, polyamides (for example Nylon"), polyesters, polypropylene, and
polyethylene. Preferably
the monofilaments have a diameter in the range of 0.02mm to 0.5mm, and have a
Shore hardness of
between 35A to 90A or a Shore hardness between 40D to 90D.
The pliable threads 30a and 30b are preferably made from natural or synthetic
spun yams such
as, for example, acrylic, cotton, cellulose, or polyester cotton blends, and
are more pliable than the
fibres 20a and 20b.
Referring to Figures 3 and 4 there is shown schematically two adjacent wales
A, and B of the
foundation layer 40 of the fabric of Figure 2. Each alternate wale A is
started by simultaneously
knitting a pair of continuous threads 20a, 20b, and 30a to form the first
stitches of each wale (Al, A2,
A3, and so on) of each of the two foundation layers 40. Simultaneously each
alternate wale (B 1, B2,
B3 and so on) of each foundation layer is started by knitting a pair of
continuous threads 20a, 20b, and
30b together.
As explained above when the two foundation layers 40 are separated, the
stitches 20a or 20b that
extend between the two foundation layers 40 are cut to leave discrete lengths
of the filament 20a or
20b, each of which comprises a loop 21 linked to the previous stitch and two
legs 22 that project from
the foundation layer 40 and these are modified as shown in Figures 9 and 10 to
constitute the hooks of
the fabric 10 or l Oa.
For reasons of clarity, Figure 3 only shows the threads 20a, 20b, and 30a, and
Figure 4 only
shows the threads 20a, 20b and 30b. In reality, the wales Al, A2, A3 and B 1,
B2, B3 of the fabric IOa
8
CA 02721464 2010-11-17
of Figure 2 are knitted together by passing the pliable threads 30a and 30b
transversely between
adjacent wales A and B and knitting them with the stitches of the threads 20a
and 20b as discussed
below.
In Figure 3 the loops 21 of alternate stitches (2nd, 4th, 6th and so on) along
the wale Al of each
foundation layer 40 are formed using a continuous lengths of the threads 30a
and threads 20b, whilst
the loops 21 of alternate stitches (3rd, 5th, and 7th and so on) along the
wale B 1 of the foundation
layers 40 are formed using continuous lengths of the threads 20a and yarns
30a.
In Figure 4 the loops 21 of alternate stitches (2nd, 4th, 6th and so on) along
the wale A3 of the
foundation layers 40 are formed using the thread 30b and threads 20a, whilst
the loops 21 of alternate
stitches (3rd, 5th, and 7th and so on) along the wale B 1 of the foundation
layers are formed with
threads 20b and yarns 30b. A cross sectional view taken along the length of
each wale is shown
schematically in Figure 5.
The pattern of stitching shown in Figures 3 and 4 is repeated widthways on the
needles of the
two needle beds for all the wales of the foundation layers 40 using multiple
yarns 30a and 30b and
multiple filaments 20a and 20b and along the length of the foundation layers
40, thus making it
possible to knit two fabrics 10 as shown in Figure 2 of any desired width when
the stitches 20a and
30b are cut
Figures 6 to 8 show the method of knitting the fabric of Figure 1 with
apertures or gaps "X" in
the foundation layer 40 of the fabric 10. The apertures "X" can be of any
desired geometric shape,
such as circle, honeycomb, hexagonal, or a quadrangle, or other geometric
shapes. The presence of the
apertures X improves the stretchability and deformability in the longitudinal
and the transverse
directions ofthe fabric 10 compared with that of the fabric I Oa of Figure 2.
Referring to Figure 6, the knitting process is started by knitting together a
first set of pairs of
wales (A 1, B 1), (A2, B2) and (A3, B3) spaced across the width of each
foundation layer 40 using the
9
CA 02721464 2010-11-17
threads 30a and 30b and threads 20a and 20b, following the pattern of stitches
shown in Figures 3 to
5.
Initially alternate pairs of the first set of pairs of wales are not linked to
the next adjacent pairs of
wales in the foundation layer 40. Instead, as shown in Figure 7 and the lower
part of Figure 6, each of
the linked pairs of the first set of pairs of wales in each foundation layer
are knitted using the pattern of
stitches shown in Figures 3 and 4 for a short distance.
After knitting a short distance along the pair of wales, each pair of the
first set of pairs of wales
((Al, B1), (A2, B2) and (A3, B3) and so on) in each foundation layer 40 are
split into two separate
wales and knitted with one of the wales of an adjacent pair of wales (as shown
in upper part of Figure
6 and in Figure 8) to form a second set of pairs of wales ((B 1, A2), and (B2,
A3) and so on)). The
pairs of wales ((B 1, A2) and (B2, A3) and so on)) in each foundation layer 40
are knitted together at
intervals along the length of the foundation layer 40 by extending the yams
30a and 30b into adjacent
wales and knitting them with the stitches of the yams 20a and 20b for a short
distance along the length
of the foundation layer 40.
Subsequently the pairs of wales in the second set of pairs of wales are each
split into two wales
and the split wales (A 1, B 1), (A2, B2) and (A3, B3) are knitted together as
shown in the lower part of
Figure 6, to reform the first set of wales. The pattern of stitches is
repeated along the length and
width of the foundation layers 40 to produce the desired size of fabric 10 and
thereby form apertures
"X" in the two layers 40.
As explained above, the knitted structure is removed from the needle beds of
the knitting
machine and the two foundation layers 40 are separated by cutting the stitches
of the filaments 20a or
20b that extend between the foundation layer 40 to leave two fabrics that have
discrete lengths of the
filaments 20a or 20b that comprises a loop 21 linked to the previous stitch
and two legs 22 knitted into
CA 02721464 2010-11-17
the foundation layers 40, and the two legs of each stitch are used to
constitute the hooks of the fabric
or 1 Oa, that project from the foundation layer 40 of the fabric 10.
It will be seen that as the knitting progresses, the pliable base yams 30a and
30b are allowed to
extend transversely to an adjacent wales of the foundation layers 40 and are
simultaneously knitted
5 alternately with the stitches 20a and 20b to make the foundation layers 40
but the loops 21 of the
synthetic yams 20a, 20b are linked to each other along the length of the wales
of the foundation layers
40 so that the loops 21 of each previous stitch loops around the loops 21 of
the next stitch, and leaves
ends that form short legs 22 of predetermined length projecting from the
foundation layers 40.
Referring to Figures 9 and 10 a further feature of the present invention is
shown wherein, after
10 the filaments 20a and 20b are cut the to form two separate pieces of fabric
10 or 1 Oa, the fabric 10 or
IOa is further processed by passing the fabric through a tunnel-type oven (not
shown) for heating and
melting the free ends of the legs 22 of each synthetic yam 20a, 20b to form
rounded ends 23 that
constitute "hooks" (see Figure 9). Alternatively, the free ends of the legs 22
of each synthetic yam 20a,
20b may be subjected to heating and compressed to deform the ends to form
hooks 24 as shown in
Figure 10.
With the fabrics 10 1 Oa of Figures 1 and 2 the short legs 22 of synthetic
filaments extend beyond
the surface of foundation layer 40 and project outside the foundation layer 40
and the distance or
length of the legs 22 of the synthetic yams 20a, 20b can be adjusted as
desired by during the knitting
stage by making the loops of the threads 20a and 20b that extend across the
needle beds of a looser or
tighter knit by controlling the tension of the monofilaments as they are
knitted.. The Shore harness of
the filaments 20a and 20b determines the rigidity and strength of the legs 22.
Thus, the touch-fastening anti-skidding fabrics 10 and 10a of the present
invention posses
advantages of light weight, high air permeability, and flexibility and is fit
for mass production of large
width products.
11
CA 02721464 2010-11-17
To summarize, the present invention provides a touch-fastening anti-skidding
material that is
structured to have synthetic filaments 20a, 20b of short lengths knitted
together with pliable threads
30a, 30b, that forms the foundation layer of the fabric to provide the effect
of anti-skidding which
when brought into contact with felts, rugs, flannelette, and loop cloth
(terrycloth) that have a looped or
entangling structures, will grip the other materials. Further, the synthetic
yams 20a, 20b, are tightly
knitted together and with the pliable yams 30a and 30b, so that they are not
pulled out of the
foundation layer 40 by the felts, rugs, flannelette, and loop cloth
(tenycloth) when being separated or
pulled apart from the other fabric. The present invention has excellent touch-
fastening characteristics
and better grip and resistance against skidding when in contact with other
looped or entangling
structures.
While certain novel features of this invention have been shown and described
and are pointed out
in the annexed claim, it is not intended to be limited to the details above,
since it will be understood
that various omissions, modifications, substitutions and changes in the forms
and details of the device
illustrated and in its operation can be made by those skilled in the art
without departing in any way
from the spirit of the present invention.
12
