U.S. patent application number 10/570429 was filed with the patent office on 2007-11-15 for method for coating grey goods for carpeting using a broad slotted nozzle.
Invention is credited to Gerd Ostermann, Jurgen Steckelberg.
Application Number | 20070261777 10/570429 |
Document ID | / |
Family ID | 34258498 |
Filed Date | 2007-11-15 |
United States Patent
Application |
20070261777 |
Kind Code |
A1 |
Steckelberg; Jurgen ; et
al. |
November 15, 2007 |
Method for Coating Grey Goods for Carpeting Using a Broad Slotted
Nozzle
Abstract
The invention relates to a method for coating grey goods for
carpeting (1) comprising an upper layer (21) containing filaments,
according to which a thermoplastic material (8) is applied to the
upper layer (21) of the underside of the carpet, thus bonding the
filaments in the grey goods (1). The invention also relates to a
carpet comprising an upper layer of filaments, in which a
thermoplastic material (8), which bonds the filaments in the
carpet, is applied to the upper layer (21) of the underside of the
carpet. In addition, the invention relates to a coating device for
coating carpets comprising an upper layer (21) of filaments, said
device being provided with transport elements for transporting the
carpet (1) along the coating device. The device is also equipped
with an applicator for applying the thermoplastic material (8) to
the underside of the upper layer (21) of the grey goods that are
transported past said applicator.
Inventors: |
Steckelberg; Jurgen;
(Bleckede, DE) ; Ostermann; Gerd; (Luneburg,
DE) |
Correspondence
Address: |
WOOD, HERRON & EVANS, LLP (NORDSON)
2700 CAREW TOWER
441 VINE STREET
CINCINNATI
OH
45202
US
|
Family ID: |
34258498 |
Appl. No.: |
10/570429 |
Filed: |
September 6, 2004 |
PCT Filed: |
September 6, 2004 |
PCT NO: |
PCT/EP04/09925 |
371 Date: |
June 27, 2007 |
Current U.S.
Class: |
156/72 |
Current CPC
Class: |
B29C 48/305 20190201;
B29C 48/05 20190201; D06N 7/0076 20130101; B29C 48/08 20190201;
D06N 2207/123 20130101; B29C 48/154 20190201; B05C 5/0254
20130101 |
Class at
Publication: |
156/072 |
International
Class: |
D05C 15/00 20060101
D05C015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 5, 2003 |
DE |
103 41 399.5 |
Claims
1-27. (canceled)
28. A method of making a carpet from a carpet article in a grey
state using a slot nozzle applicator having an entry edge and a
discharge slot having a pocket with a width, the carpet article
including an upper layer having filaments and an underside, the
method comprising: transporting the carpet article in the grey
state under the entry edge of the slot nozzle applicator, bending
over the filaments of the upper layer of the carpet article,
permitting the filaments to return to a standing position along the
width of the pocket of the discharge slot, and applying
thermoplastic material from the discharge slot to the underside of
the upper layer to bond the filaments to the carpet article.
29. A method according to claim 28, wherein the upper layer
comprises filaments joined in a non-ordered assembly or a laid
assembly, and the thermoplastic material penetrates into at least
one of (a) filaments at the underside of the carpet and (b)
intermediate spaces between filaments.
30. A method according to claim 28, in wherein the upper layer
comprises a carrier material arranged in a plane of the carpet
article and filament bunches are guided transversely through the
carrier material.
31. A method according to claim 30, wherein the thermoplastic
material at least partially penetrates into portions of the
filament bunches projecting from the carrier material at the
underside of the carpet article and penetrates into intermediate
spaces between the portions of the filament bunches.
32. A method according to claim 28, further comprising: heating the
upper layer at the underside of the carpet article, and applying
thermoplastic material to the heated upper layer at the underside
of the carpet article.
33. A method according to claim 28, further comprising: heating the
thermoplastic material after applying the thermoplastic material to
the upper layer.
34. A method according to claim 32, wherein heating the upper layer
further comprises using electromagnetic radiation,
35. A method according to claim 28, wherein the thermoplastic
material is a hot melt adhesive.
36. A method according to claim 28, further comprising: laminating
a carpet backing onto the underside of the upper layer after
applying the thermoplastic material.
37-45. (canceled)
46. A coating apparatus for coating carpet articles in a grey
state, the carpet articles including an upper layer having
filaments and an underside, the apparatus comprising: transport
elements for transporting the carpet articles in a transport
direction along the coating apparatus, a thermoplastic material
applicator comprising a slot nozzle for applying a thermoplastic
material to the underside of the upper layer of the carpet article
in the grey state as the carpet article is transported past said
thermoplastic material applicator, said slot nozzle comprising: a
discharge slot, an entry edge upstream of said discharge slot in
said transport direction, and at least one pocket downstream of
said discharge slot and configured to open towards the carpet
article
47. A coating apparatus according to claim 46, further comprising a
first heating element upstream of said thermoplastic material
applicator in said transport direction.
48. A coating apparatus according to claim 46, further comprising a
second heating element downstream of said thermoplastic material
applicator in said transport direction.
49. A coating apparatus according to claim 46, wherein at least one
of said first and second heating elements is an infrared radiating
device.
50. A coating apparatus according to claim 46, further comprising a
coating roller disposed opposite said thermoplastic material
applicator for supporting the carpet article.
51. A method according to claim 34, wherein the electromagnetic
radiation is infrared light.
Description
[0001] The invention relates to a method for coating grey goods for
carpeting that has an upper layer with filaments. The invention
also relates to a carpet itself that has an upper layer with
filaments, and a coating device for coating grey goods for
carpeting.
[0002] Carpets and methods for producing them are sufficiently well
known. Carpets usually have an upper layer, which may be variously
constructed. The upper layer may comprise pressed filaments, which
are also referred to as mat or felt. The filaments are entangled
with each other. Carpets of this sort are known as felts. In other
carpet types the upper layer comprises yarns that are drawn through
a layer of supporting material. The yarns are bundles of filaments.
The yarns can be drawn through the supporting material as closed
loops in a tufting process. The tufting process produces carpets
known as tufted carpets. The loops can also be cut open, however,
and the cut loops then form velour. Felts that have undergone
further processing are also sometimes referred to as velours.
[0003] Regardless of the type of carpet, the upper layers are
subjected to highdemands from abrasion and foot traffic; good
filament binding prevents the filaments from being loosened by the
later demands. There are various standardized testing procedures,
such as the Lisson test, for measuring the traffic wear resistance
of a carpet.
[0004] In the known carpets the filaments are fixed with latex. The
use of latex has proven to be disadvantageous, however. Latex does
not meet the requirements for recyclability. Procedures for
applying latex are energy-intensive, and the production lines that
use them require a lot of space. Attempts to employ other forms of
binding, for example using thermoplastic materials, have failed so
far because of the quality of the filament binding. The binding did
not meet the requirements of standardized walking, tensile and
abrasion demands.
[0005] It is therefore the object of the present invention,
according to a first aspect, to make available a method for coating
grey goods for carpeting in which binding the filaments with latex
can be dispensed with, but which nevertheless provides a
wear-resistant carpet.
[0006] According to a second aspect of the invention, the object of
the invention is to provide a durable carpet without latex binding
of the filaments.
[0007] According to a third aspect of the invention, the object of
the invention is to provide a coating device for coating grey goods
for carpeting which makes it possible to produce wear-resistant
carpets without latex binding of the filaments.
[0008] The first aspect of the problem is solved by a method for
coating a carpet according to claim 1, wherein a thermoplastic
material is applied to the upper layer on the underside of the
carpet and the filaments are bonded.
[0009] The method according to the invention makes it possible to
bind the filaments of the upper layer of grey goods for carpeting
firmly into the carpet. It has been found that adequate binding of
the filaments can be accomplished by applying a thermoplastic
material. Here a thermoplastic material is applied to the underside
of the upper layer. The thermoplastic material then bonds the
filaments in the grey goods. Compared to latex, thermoplastic
materials and hence the entire carpet are more easily recyclable.
Preferably, a particular form of slotted nozzle which will be
described later is chosen for applying the thermoplastic material.
The term thermoplastic is used here in general to mean an adhesive
based on thermoplastic material or a formulation based on
thermoplastic material.
[0010] Binding of the filaments with thermoplastic material is
usable with various types of carpeting, in particular with tufted
carpets, which may be of looped or velour type, but also with
felts, which may likewise be of looped or velour type or in the
form of fleece or needle felt.
[0011] Tufted carpets have yarns or filament bundles which are
passed through a supporting material, so that segments of filament
bundles protrude from the top and bottom sides of the supporting
material. Preferably, the segments of filament bundles are passed
through the supporting material on the underside of the carpet in
the form of loops. Carpet loops are formed by a filament bundle on
the top side of the carpet being passed through the supporting
material to the underside of the carpet, being reversed through a
loop, and being passed again from the underside of the carpet at a
(penetration) point some distance away through the supporting
material to the top of the carpet. The segments of filament bundles
on the underside of the carpet are not fixed, and are therefore
very sensitive, in part because they are drawn only loosely through
the supporting material and in part because individual filaments
can easily be pulled out of them.
[0012] Applying the thermoplastic material to the underside of the
carpet glues the entire filament bundle permanently to the
supporting material, since the thermoplastic material penetrates
into interstices and thus actually makes the carpet durable. In
addition, the thermoplastic material also penetrates at least part
way into the filament bundle, so that the filaments become bonded
together. If the thermoplastic material penetrates into the area of
the outer periphery of the filament bundles, they have as it were a
bonded protective sleeve due to the adhesive that has penetrated
into them, which makes the carpet even more durable. The segments
of filament bundles covered with thermoplastic material form
so-called nubs on the underside of the carpet.
[0013] While the filament bundles in tufted carpets form loops on
the underside of the carpet, their top sides can take various
forms; for example, they can also have cut loops. But all types of
tufted carpets are suitable for the coating according to the
invention.
[0014] In a different version of a carpet, which is also known as
felt, filaments are joined together to form the top layer by
mechanical processes such as pressing, needle-punching or fulling,
or by thermal processes. The filaments form a felt or mat. Felts
have an unorganized structure on the underside of the carpet. The
thermoplastic material is applied to the pressed upper layer on the
underside of the carpet to fix the filaments. Because surprisingly
it has turned out even with felts that filament binding can be
accomplished in a simple way by applying thermoplastic material.
Alternatively, a supporting layer can be positioned between the
pressed filaments and the thermoplastic layer, even with felts.
[0015] Preferably, the upper layer is heated on the underside of
the carpet, and a thermoplastic material is applied to the heated
upper layer on the underside of the carpet. Heating the grey goods
before applying the thermoplastic material, known as preheating, is
preferably performed when hot melt adhesives are used. Hot melt
adhesives are solid at ambient temperatures and fluid at elevated
temperatures. The hot melt adhesive cools down more slowly when the
grey goods are preheated, and is therefore able to penetrate into
the segments of filament bundles for a longer time and to bond
filaments together not only on the outer circumference but also in
the interior of the filament bundles. In the case of felts the
thermoplastic material is able to penetrate more deeply into the
mat or felt.
[0016] In an especially preferred embodiment of the invention, the
thermoplastic material is heated after it is applied to the
underside of the upper layer. Such afterheating can be combined
with the preheating. Being heated up twice enables the
thermoplastic material, in particular hot melt adhesive, to
penetrate especially deeply into the filament bundle or the mat.
There can also be a controller that controls the intensity of the
preheating and afterheating, and hence the depth of penetration of
the thermoplastic material into the filaments. Preferably, infrared
light (IR light) is used to heat the carpet. Using IR light in
combination with an adhesive that reacts to it thermally makes it
possible to dispense with complicated heating systems like those
needed when latex is used to bind the filaments.
[0017] Preferably, the thermoplastic material is applied to the
upper layer on the underside of the carpet in a contact process. A
slotted nozzle or broad slotted nozzle can be used for that
purpose. It is advantageous for the carpet to be transported past
under an entry edge of an outflow slot of the slotted nozzle. While
this is occurring, filaments bend down contrary to the transport
direction. After passing the entry edge, they can stand upright
again along the width of a pocket-like enlargement of an outflow
slot of the slotted nozzle to receive the thermoplastic material.
The pocket on the outflow slot enables a longer contact between the
grey goods and the still-flowing adhesive which is being applied,
and hence better binding of the filaments.
[0018] In a preferred refinement, a backing is laminated onto the
underside of the applied thermoplastic material. The backing can be
a fleece or netting material. To laminate the backing, all that is
needed is to apply a sufficiently thick coating of thermoplastic
material onto the underside of the upper layer, and then to
immediately laminate the backing. The thermoplastic material bonds
the backing to the underside. It is therefore not necessary to
apply an additional coating (second application) for the backing.
Hence an additional production step can be saved. A corresponding
additional coating device can be dispensed with.
[0019] The second aspect of the problem is solved by a carpet
having the features of claim 12, which has an upper layer with
filaments, and a thermoplastic material applied to the upper layer
on the underside of the carpet, which bonds the filaments in the
carpet.
[0020] The carpet according to the invention is producible by at
least one of the processes named above. The thermoplastic material
that penetrates into the nubs and/or filaments of the upper layer
on the underside of the carpet gives the carpet adequate strength
and durability to satisfy standardized demand tests.
[0021] Both felts and tufted carpets can have a supporting
material, onto or into which filaments are introduced. In this
version the thermoplastic material bonds the filaments additionally
with the supporting material.
[0022] Various choices are possible for the structure and type of
the supporting material. The supporting material may have a web
structure consisting of a plurality of synthetic threads oriented
in two different directions, where synthetic threads of the one
direction are passed alternately over and under the synthetic
threads of the other direction and hence are woven together. The
synthetic threads may also be yarns. The pattern of the weave has
holes. In this preferred version of the carpet, the bundles of
filaments are passed through the holes in the pattern of the weave.
That enables cost-effective and simple introduction of the
filaments into the carpet, which are preferably bonded onto the
structure of the weave by means of hot melt adhesive. The
supporting material may be a supporting fleece, for example a
spundbond fleece. The supporting materials can vary greatly.
[0023] The third aspect of the problem is solved by a coating
device according to the invention, for coating carpets having an
upper layer, where the coating device has transport elements to
transport the carpet along the transport device and a thermoplastic
applicator to apply a thermoplastic material to the underside of
the upper layer of the carpet being transported past the
thermoplastic applicator.
[0024] The coating device can be used to employ at least one of the
methods described above and for coating at least one of the types
of grey goods described above. The coated grey goods preferably
have a width of from less than one meter to several meters, and any
length desired. The coating device is especially well suited for
coating long runs of carpeting, which are sold as rolled goods.
[0025] In the coating device according to the invention, a
thermoplastic applicator is preferably positioned so that the
thermoplastic material flows out beneath the thermoplastic
applicator, preferably from a slotted nozzle, and is applied to the
carpet which is positioned beneath the thermoplastic applicator. In
this version no additional means are needed to transfer the
adhesive from the slotted nozzle to the carpet. The carpet
transported beneath the thermoplastic applicator is transportable
and supportable by a coating roller.
[0026] Preferably an adhesive, in particular hot melt adhesive, is
applied to the carpet. In a preferred version of the coating
device, a first heating element is located before the thermoplastic
applicator, and/or a second heating element in the transport
direction after the thermoplastic applicator. The two heating
elements, which are preferably IR radiators, are used, as described
above, to preheat and post-heat the carpet being fed through
beneath the adhesive applicator, in order to improve and support
penetration of the hot melt adhesive into the underside of the
upper layer.
[0027] It has been found especially advantageous for the
thermoplastic applicator to have a slotted nozzle for applying the
thermoplastic material, in particular adhesive, preferably hot melt
adhesive. The slotted nozzle can have an outflow slot for the
thermoplastic material, and before the outflow slot in the
direction of transport a sloping entry edge and behind the outflow
slot at least one pocket. The sloping of the entry edge toward the
carpet in the direction of transport enables uniform transporting
of the carpet under the slotted nozzle, without the carpet getting
caught. The pocket located after the outflow aperture collects
thermoplastic material, and also serves to form a longer contact
surface between the thermoplastic material and the carpet being
transported past. The pocket enables the nubs and filaments to
stand up and relax, or to open up again after passing the entry
edge. This special form of the slotted nozzle achieves especially
firm binding of the filaments.
[0028] The invention will be described on the basis of exemplary
embodiments. The figures show the following:
[0029] FIG. 1: a schematic cross section of a preferred version of
a tufted carpet,
[0030] FIG. 2: a schematic depiction of a preferred version of a
coating device,
[0031] FIG. 3: a cross section through a preferred version of a
slotted nozzle, and
[0032] FIG. 4: a cross section through a preferred version of a
felt carpet.
[0033] The carpet 1 according to the invention which is shown in
FIG. 1 is a tufted carpet. It has a two-dimensional supporting
material 2, from which segments of filament bundles 3 protrude on
the underside of the carpet. Additional segments of filament
bundles 4 protrude from the supporting material 2 on the top side
of the carpet. The segments of filament bundles 4 on the top side
of the carpet and the supporting material 2 form an upper layer of
the tufted carpet. Neighboring segments of filament bundles 3 on
the underside of the carpet are joined into carpet loops 5 on the
underside of the carpet. Neighboring segments of filament bundles 4
on the top side of the carpet are joined into carpet loops 6 on the
top side of the carpet. FIG. 1 shows an individual filament bundle
7, portions of which form filament bundle segments on the underside
of the carpet 3 and on the top side of the carpet 4. Along its
length the filament bundle 7 is pulled alternately from above to
below and vice versa through the supporting material 2, thereby
forming along its length the offset carpet loops on the underside 5
and top side 6 of the carpet.
[0034] On the underside of the carpet a hot melt adhesive 8 is
applied to the filament bundle segments 3 that protrude from the
underside of the carpet and to the underside of the supporting
material 2. The hot melt adhesive 8 partially or completely
penetrates the filament bundle segments 3 on the underside of the
carpet, and forms nubs. On the one hand, the hot melt adhesive 8
bonds the filament bundle segment 3 firmly to the supporting
material 2, and on the other hand it firmly attaches the filament
bundle segments 3 on the underside of the carpet together. Because
the hot melt adhesive 8 penetrates into the filament bundle
segments 3 on the underside of the carpet, it bonds the individual
filaments on the outer periphery of the filament bundle 7 together
there, and thereby prevents individual filaments from being able to
be pulled out of the filament bundle segments 3 on the underside of
the carpet.
[0035] The supporting material 2 has a woven or braided structure
(not drawn). In two directions that are perpendicular to each
other, synthetic yarns are positioned parallel to each other in
each of the two directions. The synthetic yarns of the one
direction are alternately passed over and under the synthetic yarns
of the other direction. After the binding of the nubs and
filaments, a backing can be laminated onto the layer of adhesive on
the underside of the carpet.
[0036] The filament bundles 7 are passed approximately vertically
through the supporting material 2 at penetration points 9. At the
same time, the penetration points 8 are made by the holes formed in
the braided structure, and the filament bundles 7 are passed
through these holes. The carpet loops 3 on the underside of the
carpet form a space between themselves and the supporting material
2, which is completely filled with hot melt adhesive 8.
[0037] FIG. 2 shows a schematic representation of a coating device
for coating a carpet 1 according to FIG. 1. The coating device has
an adhesive applicator 10 which is intended for applying the hot
melt adhesive to an underside of the carpet 1. On its end nearest
the carpet, which is the lower end in FIG. 2, the adhesive
applicator 10 has a slotted nozzle 11 through which the hot melt
adhesive is applied over the surface of the carpet 1 which is
running through under the adhesive applicator 10, on the underside
of the carpet material. The carpet 1 which is running through under
the adhesive applicator 10 is supported by a coating roller 12,
which is positioned below and opposite the adhesive applicator 10.
Between the adhesive applicator 10 and the coating roller 12 there
is a small intermediate space through which the carpet 1 is
transported. The interval between coating roller 12 and adhesive
applicator 10 is adjustable by adjusting the height of the adhesive
applicator 10. The height adjustability of the adhesive applicator
10 is indicated by the double-ended arrow. The application with the
adhesive applicator 10 is contact application. The transport
direction of the carpet 1 is identified by the two single-ended
arrows. Before the adhesive applicator 10 in the transport
direction of the carpet 1 the underside of the carpet is uncoated,
and after the adhesive applicator 10 in the transport direction the
carpet 1 is coated with the hot melt adhesive 8.
[0038] Positioned before and after the adhesive applicator 10 in
the transport direction of the carpet 1 are a first infrared
radiator 13 and a second infrared radiator 14, respectively. The
purpose of the first infrared radiator 13 is to preheat the
underside of the carpet. The purpose of the second infrared
radiator 14, positioned after the adhesive applicator 10, is to
post-heat the carpet 1. Preheating and post-heating the carpet
enables the hot melt adhesive to remain in the fluid state for a
longer time, and thus to penetrate deeper into the filament bundles
and/or the structure of the weave. The depth of penetration can be
controlled or influenced on the basis of the intensity of the
post-heating and preheating.
[0039] Located before and after the support roller 12 in the
transport direction of the carpet 1 are additional first 15 and
second 16 deflecting rollers, which support the carpet 1 and bring
it into the desired position.
[0040] FIG. 3 shows details of a slotted nozzle 11 according to the
invention. The adhesive applicator 10 has a slotted nozzle 11. The
carpet 1 is transported in the direction indicated by the arrow. In
this exemplary embodiment it is tufted carpeting fabric. However it
is also possible with the slotted nozzle 10 according to the
invention to coat felt, velour, or fleece fabrics. The transport
direction corresponds to the rear view in FIG. 2. The slotted
nozzle 10 has an outflow slot 17 that extends across the entire
width of the slotted nozzle 10. The hot melt adhesive emerges from
the outflow slot. Positioned before the outflow slot in the
transport direction is an entry edge 18. The entry edge slopes down
obliquely to the carpet 1 in the transport direction. Because of
the slope of the entry edge, the carpet 1 does not get caught on
the slotted nozzle 11. After the outflow slot in the transport
direction there is at least one pocket 19 on the end of the slotted
nozzle 10 toward the carpet fabric. Hot melt adhesive that flows
from the outflow slot 17 is collected in the pocket 19. Because of
the longer contact surface with the carpet 1 formed by the pocket
19, the hot melt glue can penetrate better into the nubs and
filaments and their interstices. At its end facing away from the
outflow slot 17 the pocket has a tear-off edge 20 for the hot melt
adhesive 8.
[0041] The felt carpet shown in FIG. 4, like the tufted carpet in
FIG. 1, can be produced by the coating device described above. The
felt has a pressed upper layer 21 of filaments. It is true that the
filaments are joined or felted together with each other
mechanically, thermally or chemically, but even here the filaments
must be bound on the underside of the upper layer in order to make
the felt carpet sufficiently durable. Only the application of the
hot melt adhesive 8 gives the carpet sufficient strength.
* * * * *