1. Technical Field
[0001] The present invention concerns a shoe, in particular a sports shoe.
2. Prior art
[0002] In general, a show comprises a sole and an upper fixed thereto. The sole and the
upper are made of leather in case of classic shoes, and, as a rule, of various synthetic
materials in case of sport shoes.
[0003] A shoe differs from a sock in that the upper of the shoe provides the foot with much
greater stability than a sock does. The foot is fixed much tighter by an upper than
it is by a sock. Moreover, the shoe sole protects the foot from injuries and provides
cushioning, i.e. the sole absorbs impacts of forces, e.g. during running. By use of
a suitable material, e.g. rubber and/or profiling, a shoe sole furthermore provides
the necessary static friction with the underground. A sock is not able to fulfil the
above-described functions of a shoe.
[0004] In case of a common shoe, the foot of the wearer of the shoe is completely surrounded
by the upper and the sole, i.e. the individual toes of the foot sit next to each other.
Furthermore, the toes rest on the sole such that each respective toe touches the sole
as a whole. It is not possible for a toe to have individual contact to the ground
via the sole. While the toes are able to move inside the shoe, they can only exert
force on the sole in their entirety.
[0005] This circumstance is felt to be disadvantageous and unnatural. From a foot-medical
point of view, walking barefoot is considered ideal, wherein the toes are able to
move freely to the fullest extent and each toe having direct contact to the ground
and being able to feel it.
[0006] Walking barefoot, however, is only possible comfortably and without risk on soft
ground. Even small stones are perceived as uncomfortable and involve the risk of injuring
the foot, just as pieces of broken glass. In addition, especially in winter, the ground
outdoors is generally too cold to allow comfortable barefoot walks.
[0007] In order to give the wearer of a shoe a more natural feeling when walking - similar
to walking barefoot -, on the one hand, and to protect the foot from injuries and
cold on the other hand, shoes are known which comprise individual portions for receiving
the toes. Each toe can move the portion in which it is placed independently from other
portions. This enables each toe to make contact with the ground individually and to
feel the ground. Thereby, the walking comfort is similar to the feeling of walking
barefoot, but, at the same time, the shoe sole protects the foot from injuries and
cold.
[0008] US 2007/0144039 A1, for example, relates to a piece of footwear which allows the independent movement
of the toes of the wearer of the piece of footwear while providing comfort, protection
and improved haptic feedback.
[0009] However, it has proven disadvantageous with such shoes that the connection between
the different portions is perceived as uncomfortable for the toes. The portions are
often sewn together or glued together, so that there is a thick and clearly perceptible
seam between the toes. This is perceived as uncomfortable and may even cause abrasions
in the spaces between the toes.
[0010] DE 10 2011 055 154 A1 refers to a sock for covering a foot as well as the use of firm and cut-resistant
yarns for socks. A piece of footwear is provided which is formed in a sock-like manner,
surrounds the individual toe areas and consists of a material which is at least partially
cut-resistant.
[0011] DE 20 2007 011 165 U1 refers to a piece of footwear which - particularly in the design of a sock or a knee
sock - substantially consisting of a formed knee-sock element, at least partially
covers the foot as well as a sole element, with the knee sock and the sole element
being connected to each other as one piece.
[0012] The solutions suggested by
DE 10 2011 055 154 A1 and
DE 20 2007 011 165 U1 differ considerably from a shoe or an upper. As was already explained above, a sock
is not able to provide the foot - particularly in the field of sports - with the necessary
stability. Furthermore, the suggested solutions lack any kind of cushioning, which
is especially indispensable during running, in order to protect the joints from jerky
impacts of forces.
[0013] The present invention therefore has the aim of providing a shoe - particularly a
sports shoe - which confers a walking feeling similar to walking barefoot without
causing an uncomfortable sensation in the spaces between the toes.
3. Summary of the invention
[0014] According to a first aspect of the present invention, this problem is solved by means
of an upper for a shoe, in particular a sports shoe, whereby the shoe comprises a
plurality of first portions for receiving at least one toe of a foot, wherein the
first portions can be moved substantially independently of each other, and wherein
the first portions comprise knitwear.
[0015] The upper according to the invention comprises first portions for receiving at least
one toe of a foot each. The first portions can be moved substantially independently
of each other in order to enable the toes to move freely to a certain extent, i.e.
the toes are not restricted in their movement as is the case with a common shoe. Thereby,
in case of movement of a portion, neighboring portions can also be moved slightly
due to friction or transmission of forces over the upper and/or an existing sole.
[0016] Due to the fact that the first portions are able to move substantially independently,
the toes, too, can be moved independently of each other to a large extent. This produces
a natural walking feeling similar to walking barefoot. The toes can move freely and
have individual contact with the ground and are able to feel it. Moreover, gripping
movements of the toes are possible, which are indispensable in certain types of sport,
such as climbing.
[0017] Due to the fact that the first portions are formed as knitwear, there is a possibility
to avoid thick seams at the joints of the portions. For example, the portions may
be manufactured as one-piece knitwear on a corresponding machine. Thereby, the portions
are already joined together without seams during the manufacturing process. Another
possibility would be to join the first portions by means of linking. In this regard,
the edges of the portions can be joined together in a course-oriented manner, i.e.
stitch by stitch, e.g. on a corresponding linking machine without producing thick,
irritating seams.
[0018] It has to be pointed out that the above-mentioned techniques, which avoid thick,
irritating seams, are rendered possible only by using knitwear.
[0019] In a preferred embodiment of the invention, the first portions are formed in one
piece. Thereby, thick, irritating seams are avoided. It is possible to manufacture
one-piece knitwear on a corresponding weft-knitting or warp-knitting machine in a
simple, cost-effective and quick manner. Due to the fact that the first portions are
already joined together during the manufacturing process, a corresponding subsequent
work step is not necessary.
[0020] In an alternative embodiment of the invention, the first portions are joined together
by means of linking. Linking enables the stitch-oriented joining of the edges of knitwear
without creating thick, irritating seams. Linking can be used both in weft-knitted
fabrics and in warp-knitted fabrics.
[0021] Preferably, the first portions are substantially joined without seams, i.e. the joining
of the portions between the toes is made without seams. In addition, the knitwear
can comprise seams in other areas which are not arranged between the toes (e.g. ornamental
seams). With the seamless joints of the first portions, no seams whatsoever are produced
in the spaces between the toes, such seams which are perceived as particularly irritating.
[0022] Preferably, an individual first portion is provided for each toe. Thereby, each toe
is able to move freely to the fullest extent and can be moved independently of the
toes next to it. The walking feeling is hence most similar to walking barefoot.
[0023] Preferably, the knitwear comprises at least one weft-knitted area. This may be manufactured,
for example, by means of a weft-knitting machine which allows the simple, cost-effective
and fast manufacture of knitwear.
[0024] Particularly preferably, the weft-knitted areas are flat-knitted. Further preferably,
the knitwear is weft-knitted as two layers. Further preferably, the two layers are
connected such on the sides that first portions are created.
[0025] In a preferred embodiment of the invention, the at least one weft-knitted area is
weft-knitted three-dimensionally. Three-dimensional (3D) weft-knitting allows the
weft-knitted fabric to be provided with a shape adjusted to the foot directly during
the weft-knitting process. Separate cutting is not required. The shape of the toes,
the instep or the heel can also be weft-knitted directly into the knitwear.
[0026] In a preferred embodiment of the invention, the upper including the first portions
are formed as one-piece knitwear. This allows a simple, cost-effective and fast manufacture
of the whole upper. Subsequent work steps for joining the first portions between each
other and with the rest of the upper are not necessary. In addition, the produced
waste is reduced to a minimum.
[0027] In an alternative embodiment of the invention, the knitwear of the upper is made
on a circular weft-knitting machine. Circular weft-knitting machines enable the simple
manufacture of the first portions, which should follow as far as possible the round
shape of the toe and thus, due to their most tubular form possible, are very well
suited for being manufactured on a circular knitting machine.
[0028] In an alternative, preferred embodiment of the invention, the knitwear comprises
at least one warp-knitted area. Warp-knitted fabric can be manufactured cost-effectively
and, above all, quickly.
[0029] Preferably, the at least one warp-knitted area is warp-knitted three-dimensionally.
Three-dimensional (3D) warp-knitting allows the warp-knitted fabric to be provided
with a shape adjusted to the foot directly during the warp-knitting process. Separate
cutting is not required. The shape of the toes, the instep or the heel can also be
warp-knitted directly into the knitwear.
[0030] Preferably, the knitwear of the upper is weft-knitted on a flat weft-knitting machine.
The weft-knitted fabric can be manufactured simply and cost-effectively on a flat
weft-knitting machine.
[0031] Preferably, at least one first portion comprises a first area having an elastic yarn.
Further preferably, the first portion comprises a second area, wherein the first area
comprises a more elastic yarn than the second area. In this way, at least one first
portion with an elastic area is produced, whereby the first portion can adapt optimally
to the toe. An elastic area which is, e.g., arranged in a transversal direction to
the toe allows the first portion associated with the toe to adapt to the length of
the latter.
[0032] Preferably, the first portions overlap at least in part. Due to this, an even more
comfortable feeling is created between the toes, as they are less spread, this being
more similar to walking barefoot.
[0033] Preferably, at least one first portion comprises a second yarn in addition to a first
yarn of the knitwear. Preferably, the second yarn is a stabilizing yarn. This stabilizes
the toes in the longitudinal direction and laterally and the toes are kept in position
in relation to a sole. A slipping of the toes beyond the sole is reduced or prevented
completely.
[0034] Preferably, the second yarn is arranged on a tip of a toe and further preferably
extends to above the toenail and along the side of a toe. In this manner, the second
yarn acts like a toe cap which reduces or completely prevents slipping of the toe
and protects the latter.
[0035] Preferably, the second yarn is a melted yarn or a rubberized yarn. A melted yarn
or a rubberized yarn can be worked into the knitwear during the manufacturing process,
e.g. as an additional yarn. Then, the melted yarn can subsequently be melted by heat,
so that it forms reinforced areas when cooling down. The rubberized yarn ensures increased
adhesion to the ground surface and increased abrasion resistance.
[0036] The necessary stability of the toes which reduces or prevents sliding relative to
the sole, may be achieved, in addition or alternatively to the second yarn, by imprinting
or coating the first portion. The imprinting or coating may e.g. be polyurethane (PU),
a polymer or rubber.
[0037] The upper preferably further comprises an elastic yarn. An elastic yarn worked into
the upper allows a simple size adjustment to the respective foot size as well as an
overall better fit. Moreover, slipping into the upper is facilitated and lacing can
be done without. Lacing, a hook and loop tape or a strap may additionally be affixed
to the upper, however.
[0038] According to a further aspect of the present invention, a shoe, particularly a sports
shoe, comprises an upper as described above and a sole which has second portions which
correspond to the first portions of the upper and which are each linked with these.
In this regard, the second portions can correspond to the first portions with regard
to their number. This is not compulsory, however. Thus, there can be more first portions
than second portions or vice versa. In addition or alternatively, the second portions
may correspond to the first portions with regard to their dimensions, with these dimensions
not having to be exactly identical. Thus, a first portion may, for example, be smaller
than a corresponding second portion and vice versa. Due to the fact that the first
and the second portions correspond to each other, a shoe is obtained which allows
the greatest possible freedom of movement for the toes and a natural walking feeling,
with thick, irritating seams between the toes being avoided.
[0039] Preferably, at least a subsection of the sole together with the upper is formed as
one-piece knitwear. This allows a simple, cost-effective and fast manufacture. At
the same time, the material waste is reduced to a minimum.
[0040] Preferably, the shoe comprises a midsole. Preferably, the latter is arranged within
the one-piece knitwear. The one-piece knitwear can then form an outer sole in the
area of the sole, while the midsole may assume a cushioning function, for example.
[0041] The midsole is preferably arranged detachably. In this manner, the shoe can e.g.
be adjusted to the respective area of application or alternatively or additionally
to the weight of the wearer. Moreover, the shoe would be easy to dispose of, by the
midsole and the knitwear being disposed of separately.
[0042] Preferably, the sole is weft-knitted or warp-knitted. A weft-knitted or warp-knitted
sole can be manufactured cost-effectively on a corresponding machine with a minimum
of material waste. By using techniques described below, a weft-knitted or warp-knitted
sole can be precisely adapted to the requirements and the field of application of
the shoe.
[0043] In a preferred embodiment, the sole is reinforced by coating. This may additionally
or alternatively provide the sole with stability in a simple manner. Depending on
the coating, the sole can alternatively or additionally also be made water-resistant,
abrasion-resistant or firm.
[0044] Preferably, the coating is an applied polymer. This may be polyurethane, for example.
The polymer may be applied subject to heat and pressure. Alternatively, the polymer
may be sprayed on. Alternatively, the coating is a rubber coating. This has high static
friction, i.e. good "grip". Moreover, rubber coating is very abrasion-resistant.
[0045] In a preferred embodiment, the sole is additionally or alternatively reinforced by
an additional yarn, i.e. in addition to the yarn of the knitwear. Preferably, it is
a rubber yarn. Alternatively or additionally, it is a monofilament. A yarn may e.g.
simply be weft-knitted or warp-knitted into the knitwear of the sole during weft-knitting
or warp-knitting.
[0046] In a further preferred embodiment, the sole comprises a spacer weft-knitted fabric
or a spacer warp-knitted fabric. In this manner, additional cushioning can be achieved
or the sole of the shoe can be isolated against cold. The spacer weft-knitted fabric
or spacer warp-knitted fabric is preferably provided with a filling. This may be a
particle foam, foam material or another suitable filling material.
[0047] Further preferably, the sole is manufactured from a spacer weft-knitted fabric or
spacer warp-knitted fabric. In this manner, a sole with cushioning may be obtained
in one working step.
[0048] Preferably, the sole is reinforced depending on a wearer of the shoe. Further preferably,
depending on the wearer's running style, the sole is additionally or alternatively
reinforced depending on the intended use of a shoe by a wearer. For example, for a
runner who touches the ground first with his heel, the heel section of the sole could
be specially reinforced in order to allow additional shock absorption.
[0049] Preferably, the thickness of the sole is determined depending on the weight of a
wearer of the shoe. Preferably, the thickness of the sole can additionally or alternatively
be determined depending on the use of the shoe by a wearer. This enables the optimum
adaption of the properties of the sole to the requirements of the wearer of the shoe.
[0050] A further aspect of the present invention concerns a method of manufacturing an upper
as described above with the step of providing a plurality of first portions for receiving
at least one toe of the foot, whereby the upper is formed such that the first portions
can be moved substantially independently of each other and whereby the first portions
are formed as knitwear.
4. Short description of the drawings
[0051] Aspects of the present invention will be explained in more detail with reference
to the accompanying figures in the following. These figures show:
- Fig. 1a:
- schematic representation of textile structures which can be used for the present invention;
- Fig. 1b:
- a schematic representation of a weft-knitted fabric with a filler yarn which can be
used for the present invention;
- Fig. 2:
- three different interlaces of a warp-knitted fabric which can be used for the present
invention;
- Fig. 3:
- course and wale of a weft-knitted fabric which can be used for the present invention;
- Fig. 4:
- stitch forming by latch needles during weft-knitting;
- Fig. 5a:
- an embodiment of an upper which can be used for the present invention, with two connected
textile areas;
- Fig. 5b:
- an alternative embodiment of an upper which can be used for the present invention,
with two connected textile areas;
- Fig. 6:
- three cross-sections (Fig. 6a, 6b and 6c) of an embodiment of an upper connected to
a shoe sole by means of adhesive tape which can be used for the present invention;
- Fig. 7:
- cross-sectional views of fibers for yarns used in knitwear which can be used for the
present invention;
- Fig. 8:
- front view and back view of a knitwear which can be used for the present invention;
- Fig. 9:
- a schematic top view of an upper according to the invention;
- Fig. 10:
- a schematic partial view of an upper according to the invention;
- Fig. 11:
- a schematic side view of a shoe comprising an upper according to the invention;
- Fig. 12:
- a schematic partial view of a shoe comprising an upper according to the invention;
- Fig. 13:
- a side view of an embodiment of a shoe comprising an upper according to the invention;
- Fig. 14:
- a view of the bottom side of a shoe comprising an upper according to the invention.
5. Detailed description of preferred embodiments
[0052] In the following, embodiments and variations of the present invention are described
in more detail by means of an upper for a shoe, in particular a sports shoe.
[0053] The use of knitwear allows products such as an upper or a sole of a shoe, such as
an insole, strobel sole, midsole and / or outer sole to be equipped with areas with
different characteristics providing different functions with low production effort.
The properties include bendability, stretchability (expressed as Young's modulus,
for example), permeability to air and water, thermoconductivity, thermal capacity,
moisture absorption, static friction, abrasion resistance, hardness and thickness,
for example.
[0054] Various techniques are applied in order to achieve such characteristics or functions,
which will be described in the following. This includes suitable techniques in manufacturing
knitwear such as knitting techniques, the selection of fibers and yarns, coating the
fibers, yarns or knitwear with polymer or other materials, the use of monofilaments,
the combination of monofilaments and polymer coating, the application of fused/melted
yarns, and multi-layer textile material. In general, the yarns used for the manufacture
of knitwear may be quipped, i.e. coated accordingly. In addition or alternatively,
the finished knitwear may be equipped accordingly.
[0055] Another aspect of providing functions concerns the specific use of knitwear for certain
areas of a product, for example of an upper or a sole, and the connection of different
parts by means of suitable connection techniques. The mentioned aspects and techniques
as well as other aspects and techniques will be explained in the following.
[0056] The described techniques can be used individually or they can be combined in any
manner.
Knitwear
[0057] Knitwear used in the present invention is divided into weft-knitted fabrics and single-thread
warp-knitted fabrics on the one hand and multi-thread warp-knitted fabrics on the
other hand. The distinctive characteristic of knitwear is that it is formed of interlocking
yarn or thread loops. These thread loops are also referred to as stitches and can
be formed of one or several yarns or threads.
[0058] Yarn or thread are the terms for a structure of one or several fibers which is long
in relation to its diameter. A fiber is a flexible structure which is rather thin
in relation to its length. Very long fibers, of virtually unlimited length with regard
to their use, are referred to as filaments. Monofilaments are yarns consisting of
one single filament, that is, one single fiber.
[0059] In weft-knitted fabrics and single-thread warp-knitted fabrics, the stitch formation
requires at least one thread or yarn, with the thread running in longitudinal direction
of the product, i.e. substantially at a right angle to the direction in which the
product is made during the manufacturing process. In multi-thread warp-knitted fabrics,
the stitch formation requires at least one warp sheet, i.e. a plurality of so-called
warps. These stitch-forming threads run in longitudinal direction, i.e. substantially
in the direction in which the product is made during the manufacturing process.
[0060] Fig. 1a shows the basic difference between a woven fabric
10, weft-knitted fabrics
11 and
12 and a warp-knitted fabric
13. A woven fabric
10 has at least two thread sheets which are usually arranged at a right angle to one
another. In this regard, the threads are placed above or underneath each other and
do not form stitches. Weft-knitted fabrics
11 and
12 are created by knitting with one thread from the left to the right by interlocking
stitches. View
11 shows a front view (also referred to as the front loop fabric side) and view
12 a back view (also referred to as the back loop fabric side) of a weft-knitted fabric.
The front loop and back loop product sides differ in the run of the legs
14. On the back loop fabric side
12 the legs
14 are covered in contrast to the front loop fabric side
11.
[0061] An alternative of a weft-knitted fabric which can be used for the present invention
with a so-called filler yarn
15 is shown in
Fig. 1b. A filler yarn
15 is a length of a thread placed between two wales in longitudinal direction, which
is held by transverse threads of other weave elements. By the filler yarn
15 being combined with other weave elements the properties of the weft-knitted fabric
are influenced or various pattern effects are achieved. Stretchability of the weft-knitted
fabric in the direction of the wales can for example be reduced by a filler yarn
15.
[0062] Multi-thread warp-knitted fabric
13 is created by warp-knitting with many threads from top down, as shown in
Fig. 1a. In doing so, the stitches of a thread are interlocked with the stitches of the neighboring
threads. Depending on the pattern according to which the stitches of the neighboring
threads are interlocked, one of the seven basic connections (also referred to as "interlaces"
in multi-thread warp-knitting) pillar, tricot, 2x1 plain, satin, velvet, atlas and
twill are created, for example. By way of example, the interlaces tricot
21, 2x1 plain
22 and atlas
23 are shown in
Fig. 2. A different interlocking results depending on how the stitches of thread
24, which is highlighted by way of example, are interlocked in the stitches of neighboring
threads. In the tricot interlace
21, the stitch-forming thread zigzags through the knitwear in the longitudinal direction
and binds between two neighboring wales. The 2x1 plain interlace
22 binds in a manner similar to that of the tricot interlace
21, but each stitch-forming warp skips a wale. In the atlas interlace
23 each stitch-forming warp runs to a turning point in a stairs-shape and then changes
direction.
[0063] Stitches arranged above each other with joint binding sites are referred to as wales.
Fig. 3 shows a wale as an example of a weft-knitted fabric with reference number
31. The term wale is also used analogously in warp-knitted fabrics. Accordingly, wales
run vertically through the mesh fabric. Rows of stitches arranged next to one another,
as shown by way of example for a weft-knitted fabric with reference number
32 in
Fig. 3 are referred to as courses. The term course is also used analogously in warp-knitted
fabrics. Accordingly, courses run through the mesh fabric in the lateral direction.
[0064] Three basic weft-knitted structures are known in weft-knitted fabrics, which can
be recognized by the run of the stitches along a wale. With plain, single Jersey,
only back loops can be recognized along a wale on one side of the fabric and only
back loops can be recognized along the other side of the product. This structure is
created on one row of needles of a knitting machine, i.e. an arrangement of neighboring
knitting needles, and also referred to as single Jersey. With rib fabric, front and
back loops alternate within a course, i.e. either only front or back loops can be
found along a wale, depending on the side of the product from which the wale is considered.
This structure is created on two rows of needles with needles offset opposite each
other. With purl fabric, front and back loops alternate in one wale. Both sides of
the product look the same. This structure is manufactured by means of latch needles
as illustrated in
Fig 4 by means of stitch transfer. The transfer of stitches can be avoided if double latch
needles are used, which comprise both a hook and a latch at each end.
[0065] An essential advantage of knitwear over weaved textiles is the variety of structures
and surfaces which can be created with it. It is possible to manufacture both very
heavy and / or stiff knitwear and very soft, transparent and / or stretchable knitwear
with substantially the same manufacturing technique. The parameters by means of which
the properties of the material can be influenced substantially are the pattern of
weft-knitting or warp-knitting, the used yarn, the needle size or the needle distance,
and the tensile strain subject to which the yarn is placed on the needles.
[0066] The advantage of weft-knitting is that certain yarns can be weft-knitted in at freely
selectable places. In this manner, selected zones can be provided with certain properties.
For example, an upper for a soccer shoe can be provided with zones made from rubberized
yarn in order to achieve higher static friction and thus enable the player to better
control the ball. With certain yarns being weft-knitted in at selected places, no
additional elements have to be applied.
[0067] Knitwear is manufactured on machines in the industrial context. These usually comprise
a plurality of needles. In weft-knitting, latch needles
41 are usually used, which each comprise a moveable latch
42, as illustrated in
Fig. 4. This latch
42 closes the hook
43 of the needle
41 such that a thread
44 can be pulled through a stitch
45 without the needle
41 being caught on the stitch
45. In weft-knitting, the latch needles are usually moveable individually, so that every
single needle can be controlled such that it catches a thread for stitch formation.
[0068] A differentiation is made between flat-knitting and circular-knitting machines. In
flat-knitting machines, a thread feeder feeds the thread back and forth along a row
of needles. In a circular-knitting machine, the needles are arranged in a circular
manner and the thread feeding correspondingly takes place in a circular movement along
one or more round rows of needles.
[0069] Instead of a single row of needles, it is also possible for a knitting machine to
comprise two parallel rows of needles. When looked at from the side, the needles of
the two rows of needles may, for example, be opposite each other at a right angle.
This enables the manufacture of more elaborate structures or weaves. The use of two
rows of needles allows the manufacture of a one-layered or two-layered weft-knitted
fabric. A one-layered weft-knitted fabric is created when the stitches generated on
the first row of needles are enmeshed with the stitches generated on the second row
of needles. Accordingly, a two-layered weft-knitted fabric is created when the stitches
generate on the first row of needles are not or only selectively enmeshed with the
stitches generated on the second row of needles and / or if they are merely enmeshed
at the end of the weft-knitted fabric. If the stitches generated on the first row
of needles are loosely enmeshed only selectively with the stitches generated on the
second row of needles by an additional yarn, this is also referred to as spacer weft-knitted
fabric. The additional yarn, for example a monofilament, is thus guided back and forth
between two layers, so that a distance between the two layers is created. The two
layers may e.g. be connected to each other via a so-called handles.
[0070] Generally, the following weft-knitted fabrics can thus be manufactured on a weft-knitting
machine: If only one row of needles is used, a one-layered weft-knitted fabric is
created. When two rows of needles are used, the stitches of both rows of needles can
consistently be connected to each other so that the resulting knitwear comprises a
single layer. If the stitches of both rows of needles are not connected or only connected
at the edge when two rows of needles are used, two layers are created. If the stitches
of both rows of needles are connected selectively in turns by an additional thread,
a spacer weft-knitted fabric is created. The additional thread is also referred to
as spacer thread and it may be fed via a separate yarn feeder.
[0071] Single-thread warp-knitted fabrics are manufactured by jointly moved needles. Alternatively,
the needles are fixed and the fabric is moved. In contrast to weft-knitting, it is
not possible for the needles to be moved individually. Similarly to weft-knitting,
there are flat single thread warp-knitting and circular single thread warp-knitting
machines.
[0072] In multi-thread warp-knitting, one or several coiled threads, i.e. threads which
are coiled next to one another, are used. In stitch formation, the individual warps
are placed around the needles and the needles are moved jointly.
Three-dimensional knitwear
[0074] Three-dimensional (3D) knitwear can also be manufactured on weft-knitting machines
and warp-knitting machines, particularly on flat-knitting machines. This is knitwear
which comprises a spatial structure although it is weft-knitted or warp-knitted in
a single process. A three-dimensional weft-knitting or warp-knitting technique allows
for spatial knitwear to be manufactured without seams, cut or manufacture in one piece
and in a single process.
[0075] Three-dimensional knitwear may, for example, be manufactured by varying the number
of stitches in the direction of the wales by partial courses being formed. The corresponding
mechanical process is referred to as "needle parking". Depending on the requirement,
this may be combined with structural variations and / or variations of the number
of stitches in the direction of the course. When partial courses are formed, stitch
formation temporarily occurs only along a partial width of the weft-knitted fabric
or warp-knitted fabric. The needles which are not involved in the stitch formation
keep the half stitches ("needle parking") until weft-knitting occurs again at this
position. In this way, it is possible bulges to be achieved, for example.
[0076] By three-dimensional weft-knitting or warp-knitting an upper can be adjusted to the
cobbler's last or the foot and a sole can be profiled, for example. The tongue of
a shoe can e.g. be weft-knitted into the right shape. Contours, structures, knobs,
curvatures, notches, openings, fasteners, loops and pockets can be integrated into
the knitwear in a single process.
[0077] Three-dimensional knitwear can be used for the present invention in an advantageous
manner.
Functional knitwear
[0078] Knitwear and particularly weft-knitted fabric may be provided with a range of functional
properties and used in the present invention in an advantageous manner.
[0079] It is possible by means of a weft-knitting technique to manufacture knitwear which
has different functional areas and simultaneously maintains its contours. The structures
of knitwear may be adjusted to functional requirements in certain areas, by the stitch
pattern, the yarn, the needle size, the needle distance or the tensile strain subject
to which the yarn is placed on the needles being selected accordingly.
[0080] It is possible, for example, to include structures with large stitches or openings
within the knitwear in areas in which airing is desired. In contrast, in areas in
which support and stability are desired, fine-meshed stitch patterns, stiffer yarns
or even multi-layered weft-knitting structures can be used, which will be described
in the following. In the same manner, the thickness of the knitwear is variable.
[0081] Knitwear having more than one layer provides numerous possible constructions for
the knitwear, which provide many advantages. Knitwear with more than one layer, e.g.
two, may be weft-knitted or warp-knitted on a weft-knitting machine or a warp-knitting
machine with several rows of needles, e.g. two, in a single stage, as described in
the section "knitwear" above. Alternatively, several layer, e.g. two, may be weft-knitted
or warp-knitted in separate stages and then placed above each other and connected
to each other if applicable, e.g. by sewing, gluing, welding or linking.
[0082] Several layers fundamentally increase solidness and stability of the knitwear. In
this regard, the resulting solidness depends on the extent to which and the techniques
by which the layers are connected to each other. The same yarn or different yarns
may be used for the individual layers. For example, it is possible in a weft-knitted
fabric for one layer to be weft-knitted from multi-fiber yarn and one layer to be
weft-knitted from monofilament, whose stitches are enmeshed. In particular stretchability
of the weft-knitted layer is reduced due to this combination of different yarns. It
is an advantageous alternative of this construction to arrange a layer made from monofilament
between two layers made from multi-fiber yarn in order to reduce stretchability and
increase solidness of the knitwear. This results in a pleasant surface made from multi-fiber
yarn on both sides of the knitwear.
[0083] An alternative of two-layered knitwear is referred to as spacer weft-knitted fabric
or spacer warp-knitted fabric, as explained in the section "knitwear". In this regard,
a spacer yarn is weft-knitted or warp-knitted more or less loosely between two weft-knitted
or warp-knitted layers, interconnecting the two layers and simultaneously serving
as a filler. The spacer yarn may comprise the same material as the layers themselves,
e.g. polyester or another material. The spacer yarn may also be a monofilament which
provides the spacer weft-knitted fabric or spacer warp-knitted fabric with stability.
[0084] Such spacer weft-knitted fabrics or spacer warp-knitted fabrics, respectively, which
are also referred to as three-dimensional weft-knitted fabrics, but have to be differentiated
from the formative 3D weft-knitted fabrics or 3D warp-knitted fabrics mentioned in
the section "three-dimensional knitwear" above, may be used wherever additional cushioning
or protection is desired, e.g. at the upper or the tongue of an upper or in certain
areas of a sole. Three-dimensional structures may also serve to create spaces between
neighboring textile layers or also between a textile layer and the foot, and thus
ensure airing. Moreover, the layers of a spacer weft-knitted fabric or a spacer warp-knitted
fabric may comprise different yarns depending on the position of the spacer weft-knitted
fabric on the foot.
[0085] The thickness of a spacer weft-knitted fabric or a spacer warp-knitted fabric may
be set in different areas depending on the function or the wearer. Various degrees
of cushioning may be achieved with areas of various thicknesses, for example. Thin
areas may increase bendability, for example, thus fulfilling the function of joints
or flex lines.
[0086] Moreover, the layers of a spacer weft-knitted fabric may comprise different yarns
depending on the position of the spacer weft-knitted fabric on the foot. In this way,
knitwear can be provided with two different colors for the front and the back, for
example. An upper made from such knitwear may then comprise a different color on the
outside than on the inside.
[0087] An alternative of multi-layered constructions are pockets or tunnels, in which two
textile layers or knitwear weft-knitted or warp-knitted on two rows of needles are
connected to each other only in certain areas so that a hollow space is created. Alternatively,
items of knitwear weft-knitted or warp-knitted in two separate processes are connected
to each other such that a void is created, e.g. by sewing, gluing, welding or linking.
It is then possible to introduce a cushioning material such as a foam material, eTPU
(expanded thermoplastic urethane), ePP (expanded polypropylene), expanded EVA (ethylene
vinyl acetate) or particle foam, an air or gel cushion for example, through an opening,
e.g. at the tongue, the upper, the heel, the sole or in other areas. Alternatively
or additionally, the pocket may also be filled with a filler thread or a spacer knitwear.
It is furthermore possible for threads to be pulled through tunnels, for example as
reinforcement in case of tension loads in certain areas of an upper. Moreover, it
is also possible for the laces to be guided through such tunnels. Moreover, loose
threads can be placed into tunnels or pockets for padding, for example in the area
of the ankle. However, it is also possible for stiffer reinforcing elements, such
as caps, flaps or bones to be inserted into tunnels or pockets. These may be manufactured
from plastic such as polyethylene, TPU, polyethylene or polypropylene, for example.
[0088] A further possibility for a functional design of knitwear is the use of certain variations
of the basic weaves. In weft-knitting, it is possible for bulges, ribs or waves to
be weft-knitted in certain areas, for example, in order to achieve reinforcement in
these places. A wave may, for example, be created by stitch accumulation on a layer
of knitwear. This means that more stitches are weft-knitted or warp-knitted on one
layer than on another layer. Alternatively, different stitches are weft-knitted fabric
on the one layer than on the other layer, e.g. by being weft-knitted fabric tighter,
wider or using a different yarn. Thickening is caused in both alternatives.
[0089] Ribs, waves or similar patterns may, for example, also be used at the bottom of a
weft-knitted outer sole of a shoe in order to provide a tread and provide the shoe
with better non-slip properties. In order to obtain a rather thick weft-knitted fabric,
for example, it is possible to use the weft-knitting techniques "tuck" or "half cardigan",
which are described in
"Fachwissen Bekleidung", 6th ed. by H. Eberle et al., for example.
[0090] Waves may be weft-knitted or warp-knitted such that a connection is created between
two layers of a two-layered knitwear or such that no connection is created between
the two layers. A wave may also be weft-knitted as a right-left wave on both sides
with or without a connection of the two layers. A structure in the knitwear may be
achieved by an uneven ration of stitches on the front or the back of the knitwear.
[0091] A further possibility of functionally designing knitwear within the framework of
the present invention is providing openings in the knitwear already during weft-knitting
or warp-knitting. An embodiment in the course of the present invention, which can
be combined with other embodiments, refers to an insole which comprises knitwear.
The embodiment can also be applied to a strobe sole, however. The embodiment may equally
be applied to an outer sole. An insole, strobe sole or outer sole is generally arranged
above a midsole. The midsole may comprise cushioning properties. The midsole may e.g.
comprise a foam material or consist of it. Other suitable materials are eTPU (expanded
thermoplastic urethane), ePP (expanded polyprobylene), expanded EVA (ethylene vinyl
acetate) or particle foam, for example.
[0092] The knitwear of the insole, strobe sole or outer sole comprises at least one opening
which was already weft-knitted or warp-knitted in during weft-knitting or warp-knitting
of the knitwear, respectively. The at least one opening enables the foot of a wearer
of a shoe to be able to directly touch the midsole. This improves the cushioning properties
of the shoe on the whole, so that the thickness of the midsole can be reduced.
[0093] Preferably, the at least one opening is arranged in the area of the calcaneus. An
arrangement in this position has a particularly positive effect on the cushioning
properties. Another positioning of the at least one opening is conceivable.
[0094] Yet another possibility of functionally designing knitwear within the framework of
the present invention is forming laces integrally with the knitwear of an upper. In
this embodiment the upper comprises knitwear and the laces are warp-knitted or weft-knitted
as one piece with the knitwear already when the knitwear of the upper is weft-knitted
or warp-knitted. In this regard, a first end of a lace is connected to the knitwear,
while a second end is free.
[0095] Preferably, the first end is connected to the knitwear of the upper in the area of
the transition from the tongue to the area of the forefoot of the upper. Further preferably,
a first end of a first lace is connected to the knitwear of the upper at the medial
side of the tongue and a first end of a second lace is connected to the knitwear of
the upper at the lateral side of the tongue. The respective second ends of the two
laces may then be pulled through lace eyelets for tying the shoe.
[0096] A possibility of speeding up the integral weft-knitting or warp-knitting of laces
is having all yarns used for weft-knitting or warp-knitting knitwear end in the area
of the transition from the tongue to the area of the forefoot of the upper. The yarns
preferably end in the medial side of the upper on the medial side of the tongue and
form the lace connected on the medial side of the tongue. The yarns preferably end
in the lateral side of the upper on the lateral side of the tongue and form the lace
connected to the lateral side of the tongue. The yarns are then preferably cut off
at a length which is sufficiently long for forming laces. The yarns may be twisted
or intertwined, for example. The respective second end of the laces is preferably
provided with a lace clip. Alternatively, the second ends are fused or provided with
a coating.
[0097] The knitwear is particularly stretchable in the direction of the stitches (longitudinal
direction) due to its construction. This stretching may be reduced e.g. by subsequent
polymer coating of the knitwear. The stretching may also be reduced during manufacture
of the knitwear itself, however. One possibility is reducing the mesh openings, that
is, using a smaller needle size. Smaller stitches generally result in less stretching
of the knitwear. Fine-meshed knitwear may e.g. be used at an upper (also referred
to as shoe upper).. Moreover, the stretching of the knitwear can be reduced by weft-knitted
reinforcements, e.g. three-dimensional structures. Such structures may be arranged
on the inside or the outside of an upper. Furthermore, non-stretchable yarn, e.g.
made from nylon, may be laid in a tunnel along the knitwear in order to limit stretching
to the length of the non-stretchable yarn.
[0098] Colored areas with several colors may be created by using a different thread and/or
by additional layers. In transitional areas, smaller mesh openings (smaller needle
sizes) are used in order to achieve a fluent passage of colors.
[0099] Further effects may be achieved by weft-knitted insets (inlaid works) or Jacquard
knitting. Inlaid works are areas which only provide a certain yarn, e.g. in a certain
color. Neighboring areas which may comprise a different yarn, for example in a different
color, are then connected to each other by means of a so-called handle.
[0100] During Jacquard knitting, two rows of needles are used and two different yarns run
through all areas, for example. However, in certain areas only one yarn appears on
the visible side of the product and the respective other yarn runs invisibly on the
other side of the product.
[0101] A product manufactured from knitwear may be manufactured in one piece on a weft-knitting
machine or a warp-knitting machine. Functional areas may then already be manufactured
during weft-knitting or warp-knitting by corresponding techniques as described here.
[0102] Alternatively, the product may be combined from several parts of knitwear and it
may also comprise parts which are not manufactured from knitwear. In this regard,
the parts of knitwear may each be designed separately with different functions, for
example regarding thickness, isolation, transport of moisture, etc.
[0103] An upper and/or a sole may, for example, be generally manufactured from knitwear
as a whole or it may be put together from different parts of knitwear. A whole upper
or parts of that may, for example, be separated, e.g. punched, from a larger piece
of knitwear. The larger piece of knitwear may, for example, be a circular weft-knitted
fabric or a circular warp-knitted fabric or a flat weft-knitted fabric or a flat warp-knitted
fabric.
[0104] For example, a tongue may be manufactured as a continuous piece and connected with
the upper subsequently, or it can be manufactured in one piece with the upper. With
regard to their functional designs, ridges on the inside may e.g. improve flexibility
of the tongue and ensure that a distance is created between the tongue and the foot,
which provides additional airing. Laces may be guided through one or several weft-knitted
tunnels of the tongue. The tongue may also be reinforced with polymer in order to
achieve stabilization of the tongue and e.g. prevent a very thin tongue from convolving.
Moreover, the tongue can then also be fitted to the shape of the cobbler's last or
the foot.
[0105] In an upper, it is possible for only the front part to be manufactured from knitwear,
for example. The remainder of the upper may comprise a different textile and/or material,
such as a woven fabric, for example. The front part may e.g. be located only in the
area of the toes, extend beyond the toe joints or into the midfoot area. Alternatively,
the back part of an upper may be manufactured from knitwear in the area of the heel,
for example, and e.g. be additionally reinforced with polymer coating. In general,
any desired areas of an upper or a sole may be manufactured as knitwear.
[0106] Applications such as polyurethane (PU) prints, thermoplastic polyurethane (TPU) ribbons,
textile reinforcements, leather, etc., may be applied to knitwear subsequently. Thus,
in an upper which comprises knitwear in its entirety or in parts, a plastic heel or
toe cap as reinforcement or logos and eyelets for laces may be applied on the upper,
for example by sewing, gluing or welding, as described below.
[0107] Sewing, gluing or welding, for example, constitute suitable connection techniques
for connecting individual knitwear with other textiles or with other knitwear. Linking
is another possibility for connecting two pieces of knitwear. Therein, two edges of
knitwear are connected to each other according to the stitches (usually stitch by
stitch).
[0108] A possibility for welding textiles, particularly ones made from plastic yarns or
threads, is ultrasonic welding. Therein, mechanical oscillations in the ultrasonic
frequency range are transferred to a tool referred to as a sonotrode. The oscillations
are transferred to the textiles to be connected by the sonotrode under pressure. Due
to the resulting friction, the textiles are heated up, softened and ultimately connected
in the area of the place of contact with the sonotrode. Ultrasonic welding allows
rapidly and cost-effectively connecting particularly textiles with plastic yarns or
threads. It is possible for a ribbon to be attached, for example glued, to the weld
seam, which additionally reinforces the weld seam and is optically more appealing.
Moreover, wear comfort is increased since skin irritations - especially at the transition
to the tongue - are avoided.
[0109] Connecting various textile areas may occur at quite different locations. For example,
the seams for connecting various textile areas of an upper can be arranged at various
positions, as shown in
Figures 5a and
5b. An upper
51 is shown in
Fig. 5a which comprises two textile areas
52 and
53. They are sewn to each other. The seam
54 which connects the two textile areas
52 and
53 runs diagonally from an instep area of the upper to an area of the sole in the transition
area from the midfoot to the heel. In
Fig. 5b the seam
55 also runs diagonally, but it is arranged more to the front in the direction of the
toes. Other arrangements of seams and connecting places in general are conceivable.
The seams shown in
Figures 5a and
5b can each be a thread seam, a glued seam, a welded seam or a linking seam. The two
seams
54 and
55 may each be mounted only on one side of the upper
51 or on both sides of the upper.
[0110] The use of adhesive tape constitutes a further possibility for connecting textile
areas. This may also be used in addition to an existing connection, e.g. over a sewn
seam or a welded seam. An adhesive tape may fulfil further functions in addition to
the function of connecting, such as e.g. protection against dirt or water. An adhesive
tape may comprise properties which change over its length.
[0111] An embodiment of an upper
51 connected to a shoe sole
61 by means of adhesive tape is shown
in Figures 6a, 6b and 6c. Each of
Figures 6a, 6b and 6c shows a cross-section through a shoe with different positions of the foot and the
deformations of the shoe caused by that. For example, tensile forces work on the right
side of the shoe in
Fig. 6a, whereas compression forces work on the left side.
[0112] The shoe sole
61 can be an outer soles or a midsole. The upper
51 and the shoe sole
61 are connected to each other by means of a surrounding adhesive tape
62. The adhesive tape
62 can be of varying flexibility along its length. For example, the adhesive tape
62 might be particularly rigid and not very flexible in the shoe's heel area in order
to provide the shoe with the necessary stability in the heel area. This may be achieved
by varying the width and / or the thickness of the adhesive tape
62, for example. The adhesive tape
62 may generally be constructed such that it is able to receive certain forces in certain
areas along the tape. In this way, the adhesive tape
62 does not only connect the upper to the sole but simultaneously fulfils the function
of structural reinforcement.
Fibers
[0113] The yarns or threads, respectively, used for knitwear of the present invention usually
comprise fibers. As was explained above, a flexible structure which is rather thin
in relation to its length is referred to as a fiber. Very long fibers, of virtually
unlimited length with regard to their use, are referred to as filaments. Fibers are
spun or twisted into threads or yarns. Fibers can also be long, however, and twirled
into a yarn. Fibers may consist of natural or synthetic materials. Natural fibers
are environmentally friendly, since they are compostable. Natural fibers include cotton,
wool, alpaca, hemp, coconut fibers or silk, for example. Among the synthetic fibers
are polymer-based fibers such as NylonTM, polyester, elastane or spandex, respectively,
or KevlarTM, which can be produced as classic fibers or as high-performance fibers
or technical fibers.
[0114] It is conceivable that a shoe be assembled from various parts, with a weft-knitted
or a warp-knitted part comprising natural yarn made from natural fibers and a removable
part, e.g. the insole, comprising plastic, for example. In this manner, both parts
may be disposed of separately. In this example, the weft-knitted part could be directed
to compostable waste, whereas the insole could be directed to recycling of reusable
materials, for example.
[0115] The mechanical and physical properties of a fiber and the yarn manufactured therefrom
are also determined by the fiber's cross-section, as illustrated in
Fig. 7. These different cross-sections, their properties and examples of materials having
such cross-sections will be explained in the following.
[0116] A fiber having the circular cross-section
710 can either be solid or hollow. A solid fiber is the most frequent type, it allows
easy bending and is soft to the touch. A fiber as a hollow circle with the same weight/length
ratio as the solid fiber has a larger cross-section and is more resistant to bending.
Examples of fibers with a circular cross-section are Nylon™, polyester and Lyocell.
[0117] A fiber having the bone-shaped cross-section
730 has the property of wicking moisture. Examples for materials for such fibers are
acrylic and Spandex. The concave areas in the middle of the fiber support moisture
being passed on in the longitudinal direction, with moisture being rapidly wicked
from a certain place and distributed.
[0118] The following further cross-sections are illustrated in
Fig. 7:
- Polygonal cross-section 711 with flowers; example: flax;
- oval to round cross-section 712 with overlapping portions; example: wool;
- flat, oval cross-section 713 with expansion and convolution; example: cotton;
- circular, serrated cross-section 714 with partial striations; example: rayon;
- lima bean cross-section 720; smooth surface;
- serrated lima bean cross-section 721; example: Avril™ rayon;
- triangular cross-section 722 with rounded edges; example: silk;
- trilobal star cross-section 723; like triangular fiber with shinier appearance;
- Clubbed cross-section 724 with partial striations; sparkling appearance; example: acetate;
- flat and broad cross-section 731; example: acetate in another design;
- star-shaped or concertina cross section 732;
- cross-section 733 in the shape of a collapsed tube with a hollow center; and
- Square cross-section 734 with voids; example: AnsoIV™ nylon.
[0119] Individual fibers with their properties which are relevant for the manufacture of
knitwear for the present invention will be described in the following:
- aramid fibers: good resistance to abrasion and organic solvents; non-conductive; temperature-resistant
up to 500°C.
- para-aramid fibers: known under trade names Kevlar™, Techova™ and Twaron™; outstanding
strength-to-weight properties; high Young's modulus and high tensile strength (higher
than with meta-aramides); low stretching and low elongation at break (approx. 3.5%);
difficult to dye.
- meta-aramides: known under trade names Numex™, Teijinconex™, New Star ™, X-Fiper™.
- dyneema fibers: highest impact strength of any known thermoplastics; highly resistant
to corrosive chemicals, with exception of oxidizing acids; extremely low moisture
absorption; very low coefficient of friction, which is significantly lower than that
of nylon™ and acetate and comparable to Teflon; self-lubricating; highly resistant
to abrasion (15 times more resistant to abrasion than carbon steel); nontoxic.
- carbon fiber: an extremely thin fiber about 0.005-0.010 mm in diameter, composed substantially
of carbon atoms; highly stable with regard to size; one yarn is formed from several
thousand carbon fibers; high tensile strength; low weight; low thermal expansion;
very strong when stretched or bent; thermal conductivity and electric conductivity.
- glass fiber: high ratio of surface area to weight; by trapping air within them, blocks
of glass fibers provide good thermal insulation; thermal conductivity of 0.05 W/(m
x K); the thinnest fibers are the strongest because the thinner fibers are more ductile;
the properties of the glass fibers are the same along the fiber and across its cross-section,
since glass has an amorphous structure; correlation between bending diameter of the
fiber and the fiber diameter; thermal, electrical and sound insulation; higher stretching
before it breaks than carbon fibers.
Yarns
[0120] A plurality of different yarns may be used for the manufacture of knitwear which
is used in the present invention. As was already defined, a structure of one or several
fibers which is long in relation to its diameter is referred to as a yarn.
[0121] Functional yarns are capable of transporting moisture and thus of absorbing sweat
and moisture. They can be electrically conducting, self-cleaning, thermally regulating
and insulating, flame resistant, and UV-absorbing, and may enable infrared radiation.
They may be suitable for sensorics. Antibacterial yarns, such as silver yarns, for
example, prevent odor formation.
[0122] Stainless steel yarn contains fibers made of a blend of nylon or polyester and steel.
Its properties include high abrasion resistance, high cut resistance, high thermal
abrasion, high thermal and electrical conductivity, higher tensile strength and high
weight.
[0123] In textiles made from knitwear, electrically conducting yarns may be used for the
integration of electronic devices. These yarns may, for example, forward impulses
from sensors to devices for processing the impulses, or the yarns may function as
sensors themselves, and measure electric streams on the skin or physiological magnetic
fields, for example. Examples for the use of textile-based electrodes can be found
in European patent application
EP 1 916 323.
[0124] Melted yarns may be a mixture of a thermoplastic yarn and a non-thermoplastic yarn.
There are substantially three types of melted yarns: a thermoplastic yarn surrounded
by a non-thermoplastic yarn; a non-thermoplastic yarn surrounded by thermoplastic
yarn; and pure melted yarn of a thermoplastic material. After being heated to the
melting temperature, thermoplastic yarn fuses with the non-thermoplastic yarn (e.g.
polyester or nylon™), stiffening the knitwear. The melting temperature of the thermoplastic
yarn is determined accordingly and it is usually lower than that of the non-thermoplastic
yarn in case of a mixed yarn.
[0125] A shrinking yarn is a dual-component yarn. The outer component is a shrinking material,
which shrinks when a defined temperature is exceeded. The inner component is a non-shrinking
yarn, such as polyester or nylon. Shrinking increases the stiffness of the textile
material.
[0126] A further yarn for use in knitwear are luminescent or reflecting yarns and so-called
"intelligent" yarns. Examples of intelligent yarns are yarns which react to humidity,
heat or cold and alter their properties accordingly, e.g. contracting and thus making
the stitches smaller or changing their volume and thus increasing permeability to
air. Yarns made from piezo fibers or yarn coated with a piezo-electrical substance
are able to convert kinetic energy or changes in pressure into electricity, which
may provide energy to sensors, transmitters or accumulators, for example.
[0127] Yarns may furthermore generally be reworked, e.g. coated, in order to maintain certain
properties, such as stretching, color or humidity resistance.
Polymer coating
[0128] Due to its structure, weft-knitted or warp-knitted knitwear is considerably more
flexible and stretchable than weaved textile materials. For certain applications and
requirements, e.g. in certain areas of an upper or a sole according to the present
invention, it is therefore necessary to reduce flexibility and stretchability in order
to achieve sufficient stability.
[0129] For that purpose, a polymer layer may be applied to one side or both sides of knitwear
(weft-knit or warp-knit goods), but generally also to other textile materials. Such
a polymer layer causes a reinforcement and / or stiffening of the knitwear. In an
upper it may e.g. serve the purpose of supporting and / or stiffening and / or reducing
elasticity in the toe area, in the heel area, along the lace eyelets, on lateral and
/ or medial surfaces or in other areas. Furthermore, elasticity of the knitwear and
particularly stretchability are reduced. Moreover, the polymer layer protects the
knitwear against abrasion. Furthermore, it is possible to give the knitwear a three-dimensional
shape by means of the polymer coating by compression-molding.
[0130] In the first step of polymer coating, the polymer material is applied to one side
of the knitwear. It can also be applied on both sides, however. The material can be
applied by spraying on, coating with a doctor knife, laying on, printing on, sintering,
ironing on or spreading. If it is polymer material in the form of a film, the latter
is placed on the knitwear and connected with the knitwear by means of heat and pressure,
for example. The most important method of applying is spraying on. This can be carried
out by a tool similar to a hot glue gun. Spraying on enables the polymer material
to be applied evenly in thin layers. Moreover, spraying on is a fast method. Effect
pigments such as color pigments, for example, may be mixed into the polymer coating.
[0131] The polymer is applied in at least one layer with a thickness of preferably 0.2-1
mm. One or several layers may be applied, with it being possible for the layers to
be of different thicknesses and / or colors. Between neighboring areas with polymer
coating of various thicknesses there can be continuous transitions from areas with
a thin polymer coating to areas with a thick polymer coating. In the same manner,
different polymer materials may be used in different areas, as will be described in
the following.
[0132] During application, polymer material attaches itself to the points of contact or
points of intersection, respectively, of the yarns of the knitwear, on the one hand,
and to the gaps between the yarns, on the other hand, forming a closed polymer surface
on the knitwear after the processing steps described in the following. However, in
case of larger mesh openings or holes in the textile structure, this closed polymer
surface may also be intermittent, e.g. so as to enable airing. This also depends on
the thickness of the applied material: The more thinly the polymer material is applied,
the easier it is for the closed polymer surface to be intermittent. Moreover, the
polymer material may also penetrate the yarn and soak it and thus contributes to its
stiffening.
[0133] After application of the polymer material, the knitwear is pressed in a press under
heat and pressure. The polymer material liquefies in this step and fuses with the
yarn of the textile material.
[0134] In a further optional step, the knitwear may be pressed into a three-dimensional
shape in a machine for compression-molding. For example the area of the heel or the
area of the toes of an upper can be shaped three-dimensionally over a cobbler's last.
Alternatively, the knitwear may also be directly fitted to a foot.
[0135] After pressing and molding, the reaction time until complete stiffening may be one
to two days, depending on the used polymer material.
[0136] The following polymer materials may be used: polyester; polyesterurethane pre-polymer;
acrylate; acetate; reactive polyolefins; copolyester; polyamide; co-polyamide; reactive
systems (mainly polyurethane systems reactive with H
2O or O
2); polyurethanes; thermoplastic polyurethanes; and polymeric dispersions.
[0137] A suitable range for viscosity of the polymer material is 50-80 Pa s (pascal second)
at 90-150°C. A range of 15-50 Pa s (pascal second) at 110-150°C is especially preferred.
[0138] A preferred range for the hardness of the hardened polymer material is 40-60 Shore
D. Depending on the application, other ranges of hardness are also conceivable.
[0139] The described polymer coating can be used sensibly wherever support functions, stiffening,
increased abrasion resistance, elimination of stretchability, increase of comfort
and/or fitting to prescribed three-dimensional geometries are desired. It is also
conceivable to fit e.g. an upper to the individual shape of the foot of the person
wearing it, by polymer material being applied to the upper and then adapting to the
shape of the foot under heat.
Monofilaments for reinforcement
[0140] As was already defined, a monofilament is a yarn consisting of one single filament,
that is, one single fiber. Therefore, stretchability of monofilaments is considerably
lower than that of yarns which are manufactured from many fibers. This also reduces
the stretchability of knitwear which are manufactured from monofilaments or comprise
monofilaments and which are used in the present invention. Monofilaments are typically
made from polyamide. However, other materials, such as polyester or a thermoplastic
material, would also be conceivable.
[0141] So whereas knitwear made from a monofilament is considerably more rigid and less
stretchable, this knitwear', however, does not have the desired surface properties
such as e.g. smoothness, colors, transport of moisture, outer appearance and variety
of textile structures as usual knitwear has. This disadvantage is overcome by the
knitwear described in the following.
[0142] Fig. 8 depicts a weft-knitted fabric having a weft-knitted layer made from a first yarn,
such as a multi-fiber yarn, for example, and a weft-knitted layer made from monofilament.
The layer of monofilament is weft-knitted into the layer of the first yarn. The resulting
two-layered knitwear is considerably more solid and less stretchable than the layer
made from yarn alone. If a monofilament is begun to be melted slightly, the monofilament
fuses with the first yarn even better.
[0143] Fig. 8 particularly depicts a front view
81 and a back view
82 of a two-layered knitwear
80. Both views show a first weft-knitted layer
83 made from a first yarn and a second weft-knitted layer
84 made from monofilament. The first textile layer
83 made from a first yarn is connected to the second layer
84 by stitches
85. Thus, the greater solidness and smaller stretchability of the second textile layer
84 made from the monofilament is transferred to the first textile layer
83 made from the first yarn.
[0144] A monofilament may also be begun to be melted slightly in order to connect with the
layer of the first yarn and limit stretching even more. The monofilament then fuses
with the first yarn at the points of contact and fixates the first yarn with respect
to the layer made from monofilament.
Combination of monofilaments and polymer coating
[0145] The weft-knitted fabric having two layers described in the preceding section may
additionally be reinforced by a polymer coating as was already described in the section
"polymer coating". The polymer material is applied to the weft-knitted layer made
from monofilament. In doing so, it does not connect to the material (e.g. polyamide
material) of the monofilament, since the monofilament has a very smooth and round
surface, but substantially penetrates the underlying first layer of a first yarn (e.g.
polyester yarn). During subsequent pressing, the polymer material therefore fuses
with the yarn of the first layer and reinforces the first layer. In doing so, the
polymer material has a lower melting point than the first yarn of the first layer
and the monofilament of the second layer. The temperature during pressing is selected
such that only the polymer material melts but not the monofilament or the first yarn.
Melted yarn
[0146] For reinforcement and for the reduction of stretching, the yarn of the knitwear which
is used according to the invention may additionally or alternatively also be a melted
yarn which fixes the knitwear after pressing. There are substantially three types
of melted yarns: a thermoplastic yarn surrounded by a non-thermoplastic yarn; a non-thermoplastic
yarn surrounded by thermoplastic yarn; and pure melted yarn of a thermoplastic material.
In order to improve the bond between thermoplastic yarn and the non-thermoplastic
yarn, it is possible for the surface of the non-thermoplastic yarn to be texturized.
[0147] Pressing preferably takes place at a temperature ranging from 110 to 150°C, especially
preferably at 130°C. The thermoplastic yarn melts at least partially in the process
and fuses with the non-thermoplastic yarn. After pressing, the knitwear is cooled,
so that the bond is hardened and fixed. The melted yarn may be arranged in the upper
and / or the sole. In one embodiment, the melted yarn is weft-knitted into the knitwear.
In case of several layers, the melted yarn may be weft-knitted into one, several or
all layers of the knitwear.
[0148] In a second embodiment, the melted yarn may be arranged between two layers of knitwear.
In doing so, the melted yarn may simply be placed between the layers. Arrangement
between the layers has the advantage that the mold is not stained during pressing
and molding, since there is no direct contact between the melted yarn and the mold.
Thermoplastic textile for reinforcement
[0149] A further possibility for reinforcing knitwear which is used for the present invention,
for example in an upper and / or a sole, is the use of a thermoplastic textile. This
is a thermoplastic woven fabric or thermoplastic knitwear. A thermoplastic textile
melts at least partially subject to heat and stiffens as it cools down. A thermoplastic
textile may, for example, be applied to the surface of an upper or a sole, which may
comprise knitwear, for example, by applying pressure and heat. When it cools down,
the thermoplastic textile stiffens and specifically reinforces the upper or the sole
in the area in which it was placed, for example.
[0150] The thermoplastic textile may specifically be manufactured for the reinforcement
in its shape, thickness and structure. Additionally, its properties may be varied
in certain areas. The stitch structure, the knitting stitch and / or the yarn used
may be varied such that different properties are achieved in different areas.
[0151] One embodiment of a thermoplastic textile is a weft-knitted fabric or warp-knitted
fabric made from thermoplastic yarn. Additionally, the thermoplastic textile may also
comprise a non-thermoplastic yarn. The thermoplastic textile may be applied to an
upper or a sole of a shoe, for example, by pressure and heat.
[0152] A woven fabric whose wefts and / or warps are thermoplastic is another embodiment
of a thermoplastic textile. Different yarns can be used in the weft direction and
the warp direction pf the thermoplastic woven fabric, so as to achieve different properties,
such as stretchability, in the weft direction and the warp direction.
[0153] A spacer weft-knitted fabric or spacer warp-knitted fabric made from thermoplastic
material is another embodiment of a thermoplastic textile. In this regard, e.g. only
one layer may be thermoplastic, e.g. so as to be attached to an upper or a sole. Alternatively,
both layers are thermoplastic, e.g. in order to connect the sole to the upper.
[0154] A thermoplastic weft-knitted fabric or warp-knitted fabric may be manufactured using
the manufacturing techniques for knitwear described in the section "knitwear".
[0155] A thermoplastic textile may be connected with the surface to be reinforced only partially
subject to pressure and heat so that only certain areas or only a certain area of
the thermoplastic textile connects to the surface. Other areas or another area do
not connect, so that the permeability for air and / or humidity is maintained there,
for example. The function and / or the design of e.g. an upper or a sole can be modified
by this.
Upper
[0156] Fig. 9 shows a schematic top view of a first embodiment of an upper
51 according to the invention. The upper
51 comprises a plurality of first portions
91 which are suitable for receiving at least one toe of a foot each. The toes of a wearer
of a shoe provided with an upper
51 according to the invention are positioned in the first portions
72 while the shoe is worn.
[0157] The upper
51 in
Fig. 7 comprises five first portions
91, which means that for each toe, there is an individual first portion of the plurality
of portions
91. However, it is also conceivable that two or more toes are allocated to one single
first portion.
For example, the big toe could be allocated to an individual first portion, while
the remaining toes are allocated to a mutual first portion. The upper
51 would hence comprise two first portions in total.
[0158] A toe may also be allocated to none of the first portions. Openings in the upper
51 could, for example, make one or several toes visible from outside.
[0159] The upper
51 is configured such that the first portions
91 can be moved substantially independently of each other in order to enable the toes
to move freely to a certain extent, i.e. the toes are not restricted in their movements
as it is the case with a normal shoe. The toes can create individual contact with
the ground via the sole. In this regard, in case of movement of a portion, neighboring
portions can indeed be moved along slightly due to friction or transmission of forces
over the upper
51 and/or an existing sole.
[0160] Due to the substantially independent freedom of movement of the first portions
91, the toes, too, can be moved largely independently from each other. This produces
a natural walking feeling similar to walking barefoot. The toes can move freely and
have individual contact with the ground and are able to feel it. A gripping movement
of individual toes is also possible.
[0161] The first portions
91 in
Fig. 9 are formed as knitwear, which can be manufactured as explained in the section "knitwear".
In the example of
Fig. 9, the forefoot area
92, which comprises the first portions
91, is formed as knitwear. The remaining area
93 of the upper
51 does not have to be formed as knitwear, since seams are perceived as less disturbing
in this area. It is conceivable that this area
93 is formed as a thicker, elastic woven fabric or as another conventional shoe material,
for example.
[0162] However, it is also conceivable that merely the first portions
91 of the upper
51 are formed as knitwear and no further area of the upper
51. Alternatively, the whole upper
51 can be formed as knitwear. For example, the forefoot area
92 could be weft-knitted, whereas the remaining area
93 is warp-knitted, or vice versa.
[0163] It is also conceivable that the upper
51 is formed as knitwear in one piece. For example, the upper
51 could be weft-knitted or warp-knitted continuously. In this case, there are no differing
areas
92 and
93 with regard to the use of knitwear. In this case, however, the areas
92 and
93 could differ with regard to their weft-knitted or warp-knitted structure or the used
yarns. A more open stitch structure could be used for airing on the toes in the forefoot
area
92, whereas a tighter weft-knitted fabric is used on the sides in order to increase
stability. Reinforcements such as e.g. ribs, tunnels, pockets, etc. can be weft-knitted
or warp-knitted into areas
92 or
93 in order to receive reinforcements or the like. Ribbons may be weft-knitted on.
[0164] The first portions
91 can each be manufactured individually as knitwear and then be joined together by
means of linking. During linking, the edges of the portions of knitwear are joined
together in a course-oriented manner, i.e. linked together stitch by stitch, so that
no thick seam is produced. This can e.g. be done on a linking machine.
[0165] The first portions
91 can, alternatively, be manufactured as one-piece knitwear. For example, the portions
91 can be weft-knitted on a circular knitting machine. The manufacture on a flat knitting
machine or a warp knitting machine is, however, also imaginable. On a flat weft-knitting
machine, an upper layer and a bottom layer of the knitwear can e.g. be weft-knitted
at the same time, with a respective row of needles being used for each of the two
layers, as described in the section "knitwear". The two layers can only be connected
to each other along the contour of the shoe and thus form a cavity for the foot. The
two layers may also be not fully flat weft-knitted but weft-knitted three-dimensionally,
so that the final shape corresponds to the foot, as described in the section "three-dimensional
knitwear".
[0166] By linking or manufacturing in one piece the first portions
91, no seams are produced between the first portions
91. This means that joining of the first portions
91 between the toes is made without seams. The knitwear can comprise seams in other
areas which are not arranged between the toes.
[0167] The first portions
91 can overlap at least in part, as it is shown in
Fig. 10. Here, for example, the first portion for the big toe
91a partially overlaps the neighboring first portion
91b, which, in turn, partially overlaps the neighboring first portion
91C, etc.
[0168] Not all first portions
91 have to overlap each other. The at least partially overlapping first portions
91 can e.g. be manufactured by the smallest first portion
91e being weft-knitted or warp-knitted first. Subsequently, the next bigger first portion
91d is weft-knitted or warp-knitted such that it at least partially overlaps the smaller
first portion
91e. This process is repeated until the largest first portion
91a is reached. This overlapping first portions
91 can also be weft-knitted in one go on a flat weft-knitting machine or three-dimensionally
weft-knitted into shape, for example.
[0169] The at least partial overlap of the first portions
91 causes an even more pleasant sensation between the toes, since the toes are spread
apart less and a "lumpy" feeling between the toes is reduced further or prevented.
[0170] The first portions
91 can comprise an additional yarn which, for instance, can be directly weft-knitted
or warp-knitted into the knitwear. Alternatively, the additional yarn can be worked
into the knitwear afterwards, for example, by sewing in or embroidering (on). The
additional yarn may e.g. be a stabilizing yarn, which improves the support of the
toes in the first portions
91 and thus reduces or prevents the toes slipping forward or towards the sides beyond
the sole. The additional yarn may be a melted yarn, a rubberized yarn, a yarn with
less stretchability or a thicker yarn. There can also be several stabilizing yarns
which are twisted, for example. A melted yarn can, e.g. be fused by heat and hardens
when cooling down. Thereby, a stiffened, reinforced area is formed. A rubberized yarn
has a rubber-like surface and a correspondingly high static friction and thus causes
increased adhesion to the ground surface and increased abrasion resistance.
[0171] The additional yarn may be arranged on a tip of a toe and extend to above the toenail
and along the side of a toe. In this manner, the additional yarn acts like a toe cap
which reduces or completely prevents slipping of the toe and protects the latter.
The additional yarn does not have to be processed in a sheet-like manner. It may also
be processed in a line-like manner, for example, such as weft-knitted in.
[0172] In
Fig. 7 a first area
94 in the first portion
91 of the big toe is shown which comprises an elastic yarn. Due to this, the first portion
91 is particularly elastic in this area. The first portion
91 hence simply adapts itself to the shape and size of the toe, particularly to the
length of the toe. It is conceivable that also other first portions of other areas
of the upper are formed by an elastic yarn. The elastic yarn can, for example, be
directly weft-knitted or warp-knitted into the knitwear. Alternatively, the elastic
yarn can be worked into the knitwear afterwards, for example, by sewing (on) or weft-knitting
(on).
Shoe
[0173] Fig. 11 shows a shoe
111 with an upper
51 according to the invention. Besides the upper
51, the shoe
111 comprises a sole
61. The sole can be made of leather, rubber or a synthetic material such as ethylene
vinyl acetate (EVA), for example. The sole
61 may also be weft-knitted or warp-knitted, i.e. also be formed of knitwear. The upper
51 is fixed to the sole
61, for example, by bonding, welding or sewing. The sole
61 comprises two portions
112 which correspond to the first portions of the upper
91 and are connected to them.
[0174] The top view of
Fig. 12 shows that each of the first portions
91 of the upper corresponds to one of the second portions
112 each of the sole. It is also conceivable that several first portions of the upper
correspond to one single second portion of the sole. For example, the first portion
for the big toe alone could correspond to a second portion, whereas the remaining
first portions for the other toes merely correspond to a further second portion of
the sole. The shoe would then have an upper with five first portions and a sole with
two second portions.
[0175] In case of the shoe
111 shown in
Fig. 10 and
Fig. 11, a subsection of the sole
61 together with the upper 51 can be formed as one-piece knitwear. Alternatively, the
entire sole
61 and the entire upper
61 can jointly be formed as one-piece knitwear. The manufacture of such a shoe
111 can occur made on a weft-knitting machine or a warp-knitting machine. With regard
to the manufacture of knitwear, reference is made to the section "knitwear", for example.
[0176] The sole
61 and the upper
51 can also be weft-knitted or warp-knitted separately and then joined together, e.g.
by linking, gluing, weft-knitting together, welding, etc.
[0177] The sole
61 can be additionally reinforced, as described in the sections "polymer coating", "monofilaments
for reinforcement", "combination of monofilaments and polymer coating", melted yarn"
and "thermoplastic textile for reinforcement", i.e. for example, by an applied polymer,
a rubber coating, a yarn, a spacer warp-knitted fabric and / or a spacer weft-fabric.
[0178] The reinforcement can be effected depending on the running style of a wearer of the
shoe. For a runner who, for example, prefers touching the ground with the heel first,
the heel area of the sole
61 could be reinforced correspondingly.
[0179] The thickness of the sole
61 can be determined depending on the weight of a wearer of the shoe
111. For a wearer who weighs more, a thicker sole
61 can e.g. be used than for a lighter wearer.
[0180] Alternatively or additionally, the thickness of the sole
61 can be determined depending on the use of the shoe
111 by a wearer. For example, a thicker sole
61 providing additional cushioning can be used for a running shoe than is the case for
a climbing shoe or a casual shoe.
[0181] Fig. 13 shows a side view of an embodiment of a shoe
111 which comprises an upper
51 according to the invention. The shoe
111 shown in
Fig. 13 comprises a sole
61 to which the upper
51 is fixed. The upper
51 has a forefoot area
92 made of knitwear. The area
92 comprises first portions
91 for receiving the toes of a wearer of the shoe
111. The first portions
91 are formed as knitwear. The area
93 of the upper may be manufactured from elastane, nylon, spandex, neoprene or Lycra.
The areas
92 and
93 are joined by means of a seam
131. In principal, other techniques for joining may also be used, such as sewing, gluing,
welding, linking, for example.
[0182] The first portions
91 are coated partially with a foil
132 for reinforcing and improving the abrasive properties. The foil
132 is thermoplastic and is applied to the first portions
91 by heat and pressure. Alternatively, an abrasion-resistant yarn may be weft-knitted
in and additionally or alternatively, a coating, e.g. a polymer coating, a PU print
or a rubberized print may be applied. A melted yarn may also be weft-knitted in or
embroidered on afterwards. Instead of a foil, other techniques of the ones described
above could also be used for reinforcing.
[0183] The area
93 is partially printed on, e.g. by a PU print (for example by the company Kurim, which
specializes in PU coatings e.g. for the shoe industry), in order to improve stability.
Equally, the area
92, the first portions
91 or the sole
61 could be printed on for improving stability or for optical enhancement.
[0184] Fig. 14 shows a view of the bottom of a shoe
111 which comprises an upper
51 according to the invention. The shoe
111 comprises a sole
61 with second portions
112, which are overlapped by corresponding first portions (not visible in
Fig. 14) of the upper. The sole
61 may be formed as a separate part and connected, e.g. glued to, the upper
51. The sole
61 may also be sprayed (e.g. as TPU) or vulcanized (e.g. rubber) directly onto the upper
51. The sole
61 may be formed as a coating of the upper
51. The sole
61 may also be a part of the weft-knitted fabric or warp-knitted fabric of the upper
51 and weft-knitted in or warp-knitted in e.g. as a rubberized yarn or melted yarn.
[0185] The sole
61 is provided with a profile in order to improve the traction of the shoe
111. The profile can, in principle, be adapted to the field of application of the shoe
111. A shoe which is to be used in the country could comprise a coarser and deeper profile
than a shoe which is worn in town.
[0186] The sole shown in
Fig. 12 furthermore includes an area where the sole
61 is thinner than in other areas. This area
141 is located between the area of the toes and the area of the ball of the toes and
extends along the foot's flex lines. Since the sole
61 is thinner in this area
141, the second portions
112 of the sole
61, which are connected to the first portions of the upper, are easier to snap with regard
to the remainder of the sole
61. The overall freedom of movement of the toes is thus increased.
[0187] The sole
61 shown in
Fig. 14 furthermore comprises grooves
142 and
143. The grooves
142 run substantially in the longitudinal direction of the sole
61, whereas the grooves
143 run substantially in the lateral direction of the sole
61. The grooves
142,
143 generally correspond to the foot's natural flex lines, but another path of the grooves
is also possible.
[0188] The grooves
142 and
143 have the effect that the sole
61 as a whole becomes more flexible, adapts better to the shape of the foot and allows
a more natural walking feeling similar to that of walking barefoot.