EP0647111B1

EP0647111B1 - Carpet construction

Info

Publication number: EP0647111B1
Application number: EP93915588A
Authority: EP
Inventors: Joseph R. Pacione
Original assignee: Tac Fast Systems SA
Current assignee: Tac Fast Systems SA
Priority date: 1992-06-30
Filing date: 1993-06-30
Publication date: 1997-09-03
Anticipated expiration: 2013-06-30
Also published as: RU94046352A; JP3307643B2; HK1002820A1; HU9403834D0; DE69313637D1; WO1994000043A1; EP0647111A1; CZ332894A3; CA2136210A1; CZ284062B6; JPH07508436A; ATE157521T1; DK0647111T3; PL170948B1; TW392585U; ES2108288T3; BR9306624A; SK161694A3; DE69313637T2; CA2136210C

Abstract

A carpet construction having an interposed layer of foam and a loop backing. The foam layer is manufactured with a fabric covering on both of its sides, the bottom covering having loops. A carpet backing is affixed to the foam sandwich using conventional methods. The foam sandwich can be secured to the carpet pile layer at the same time and with the same material that binds and seals the carpet pile layer. Alternatively, the foam sandwich can be manufactured, stored and later attached to the carpet which has previously been pre-coated with a binder.

Description

This invention relates to a new carpet construction and particularly to a carpet for use with a hook and loop installation device.
As shown in US-A-4 822 658, it has been found that it is possible to produce a new carpet to be installed, as for instance in wall to wall carpeting, by the use of a hook and loop system. With this previous invention, in the preferred embodiment, a carpet is manufactured with an undersurface substantially covered with loops, and this carpet is installed with a complementary tape containing hooks which are temporarily covered. The tapes are put in place on the floor and along the edges at intervals corresponding to the width of the carpet or wherever additional affixation to the floor is required. The tapes are covered so that they do not pre-maturely attach to the loops when the carpet is put in place, cut and fitted. The tape covering is then pulled off to expose the hooks and to adhere the carpet to the floor.
This earlier patent also discloses the possibility of incorporating a foam layer between the primary layer containing the carpet tufts and the underlying looped backing.
The earlier patent US-A-4 822 658 shows a carpet with a foam interposed layer. In-line lamination can work to achieve a carpet construction as shown in US-A-4 822 658. In such process, the bottom loop layer is laminated onto the foam while the foam is formed onto the layer so that the foam cures on the back of the carpet resulting in attachment of the underloop layer to the top tufted layer of the carpet.
A principle drawback of such an arrangement is that the unfinished carpet has to be brought to a foamer so that the lamination can be done on a foaming line or, alternatively, the carpet manufacturer has to invest in foaming machinery for his factory.
Further, there is considerable stress on the foam in use when it is directly attached to the carpet. Without a covering to give the foam some dimensional stability, the unsupported foam can easily shear, tear or delaminate from the carpet.
In addition, it would be highly desirable in many applications if a lower density foam could be used. However, when this method of direct application of the foam to a carpet primary layer is used, higher density foam is normally needed to give the foam enough stability.
Some carpet does have a backing such as an "action backing" of polypropylene or jute over the back of the carpet. Affixing the foam directly to such backing could reduce the stress on the foam but attempts to achieve this have caused delamination problems between the foam and the action backing.
Finally this application of foam directly to a carpet primary layer "in-line" normally requires that any covering or loop backing on the foam be placed there while the foam is setting which can create additional disadvantages.
The present invention attempts to create an improved carpet construction containing an interposed layer of foam and a loop backing.
The carpet and method of making a carpet according to the present invention are characterized in the present claims.
It has been discovered that this can be achieved by manufacturing the foam layer with a fabric covering on both sides of this layer (the bottom covering having loops) and then subsequently affixing this foam sandwich to a carpet backing using conventional methods. The foam sandwich can be secured to the carpet pile layer at the same time and with the same material that binds and seals the carpet pile layer, i.e. "in line" or the foam sandwich can be made, stored and attached in a subsequent step to the carpet which had previously been pre-coated with a binder.
This improvement can enable carpet containing a loop backing to be manufactured with existing machinery so that a pre-existing, earlier manufactured foam layer can be attached by a binder or adhesive to the back of a carpet by the use of currently available conventional carpet machinery.
Further different thicknesses or gauges of foam can be retained by a carpet manufacturer for later attachment to different carpet pile layers, as required.
A fabric covering placed on both sides of a pre-manufactured foam layer also can increase the dimensional stability of the foam to allow lower density foam to be used and can also allow, in a preferred embodiment, the use of foam not formed in-line, such as slab foam.
Fabric is preferable to a chemical or polymer covering because it can impart dimensional stability to the foam while at the same time providing some flexibility and protection to the foam from ripping and breaking.
Further, in the preferred embodiment, the upper surface fabric covering is a fabric which can have a rough outer surface, such as a hairy or loopy fabric, with upstanding threads, which will improve adhesion to the carpet backing.
While the fabric covering can be placed on the foam using conventional methods, it is desirable, in the preferred embodiment, to place the covering on the surface of the foam after the foam has formed. This prevents infiltration of the foam into the fabric covering, which is usually not desirable, particularly with respect to the lower covering of the foam layer which has the loops needed to attach the carpet to the floor.
Thus the present invention in one aspect consists of a laminated carpet for attachment to a floor without a separate underpad comprising (i) a primary layer having pile elements substantially covering a first side of the primary layer, (ii) a foam layer having a first fabric covering on an upper surface of such layer and a second covering having exposed loops on a lower surface of such layer, (iii) means for securing the first and second covering to the foam layer, and (iv) means for securing the upper surface of the first covering of the foam layer to the primary layer so that the pile elements and the loops are exposed on abutting faces of the carpet.
In another aspect the invention consists of a carpet comprising a primary layer having pile elements tufted into and through such layer and substantially covering a first side of the primary layer, a foam layer having a first fabric covering exposing threads outstanding from the upper surface of such layer and a second fabric covering exposing loops on the lower surface of such layer, and adhesive means for securing the first fabric covering of the foam layer to the primary layer so that the outstanding threads of the upper surface of the first covering and the tufts extending through the primary layer are sealed together, and so that the pile elements and the loops of the lower surface of the foam layer are exposed on abutting faces of the carpet lamination.
Certain embodiments of the invention are described with reference being made to the accompanying drawings wherein:

FIG. 1 is a sectional elevation of a preferred laminated carpet embodiment in accordance with the present invention prior to the installation of the foam layer onto the carpet backing; and
FIG. 2 is a sectional elevation of this preferred laminated carpet embodiment in which the foam layer and carpet backing have been attached together.

Referring to the drawings, figure 1 shows a conventional carpet backing 1 of polypropylene or other conventional material forming a primary layer containing yarn 3 needled through the backing to form tufted bundles 5.
A foam layer 7 is shown. Such foam layer can be made by any conventional means such as by chemically blown, frothed or pre-manufactured slab or any other means that would produce the necessary resilience, shear strength and tensile strength. In the preferred embodiment, a loopy woven or non-woven fabric covering 9 and 11 is affixed to the foam, after the foam is made, by using adhesives, flame lamination or ultrasound or any other method which produces a satisfactory peel-delamination strength without undue infiltration into the loop fabric covering, thus maintaining a high degree of flexibility.
However in some cases, it is possible, though not usually preferable, to place the covering on the foam while the foam is being formed or setting up. In this case, the benefits of gauge control and of non-penetration of the covering will not be equal to a carpet construction in which the foam has formed first, but there will still be advantages derived from the separate covering and manufacture of the foam as previously described.
Placing the covering on the foam before the foam has set has drawbacks in that the loop fabric is sometimes infiltrated to a degree that is not preferable and a board-like effect can be created as the foam hardens around and in the loop fabric.
The infiltration which can occur may also destroy or impede all or some of the loops from performing their function as was intended, due to loss of directional movement. Further, this method of in-line lamination reduces the ability to lower the weight of the loop fabric by opening the gauge. Opening the gauge to reduce the weight of the loop fabric can cause further penetration of liquid foam which could cause "bleeding" of the liquid foam to the other side of the loop fabric thus eliminating the use of some or all of the loops.
It is advantageous to have the loop layer maintain its ability to stretch in length and width. A more open gage and less penetration of the foam into the loop layer can allow the loop layer to give. This can allow completed carpet product with its attached interposed foam pad to be rolled more easily and be more flexible.
Additionally, the in-line method of depositing foam while attaching it to the carpet yarn backing does not produce the most efficient form of foam gauge control. Since the in-line lamination requires the manufacturing of the foam at the same time as its attachment to the back of the carpet, it is difficult to control the exact gauge or height of the foam during this process.
Nevertheless the principal advantages of the invention can be achieved by covering the foam on both sides with fabric as described, and it may initially be easier for some manufacturers, with their existing machinery, to add this covering while the foam is setting up notwithstanding the other disadvantages.
Preferably the loop fabric 11 is a locked loop by which is meant that the loops are firmly set into the loop backing either by the adhesive used to attach the covering to the foam, the form of loopy material that is used, or (in the non-preferred embodiment) by the infiltration of the foam into the fabric. It has been found that a knit is ideal, especially a warp or tricot knit, for having the proper degree of locked loop in the fabric. Such a warp or tricot knit is preferably used for both loop layers, however a woven or other material may also be used. The term "fabric" means any woven, non-woven, pressed material of natural or artificial fibres.
The loop layers 9 and 11 do not need to be of the same material or strength. The loop layer 9 is less critical and preferably has loops or upstanding threads to assist adhesion to the backing 5. Many coverings would be suitable if they have the desired strength, flexibility and ability to adhere to the foam.
As previously stated, the upper loop covering 9 is preferably a knit or other "locked loop" material but it could also be a fabric which has upstanding threads rather than loops such as many needle punched materials or felt or other kinds of loopy fabric in which the loops are not firmly locked in place. It is thought that the upstanding threads fill in the carpet primary layer and assist in adhesion of the foam layer to the carpet primary layer. Normally the carpet will have a "backing" of polypropylene but the invention would work equally well with a carpet without a distinct backing in which the warp and weft of the carpet forms the primary layer.
With the embodiment of figure 1 the foam material can be transported and stored, after it is covered on both sides with a loopy fabric, in an easier way than with uncovered foam. Uncovered foam rips, tears and soils easily and is not as suitable for handling, transportation and storage. In addition, the loop covering on both sides of the foam gives the foam greatly increased sheer and tensile strength while retaining and possibly even improving the foam's natural resilience.
The preferred construction uses slab foam because gauge or thickness control is easier with slab foam than with other methods of foam manufacture.
Figure 2 shows the carpet with the foam installed on a carpet backing. The foam can be installed using conventional techniques by the use of any binder or adhesive 13. If a loopy fabric is used it is preferable if the adhesive infiltrates and seals the loop material 9 and the carpet tufts 5 together.
This adhesive can be applied using conventional carpet machinery in either a one pass system in which the binder being used does both the job of encapsulation, tuft-bind and secondary backing lamination of the pre-manufactured covered foam layer, or in an end of line or post-laminate off-line system whereby a conventional primary backing with yarn needled through is backed using a light coat (e.g. "kiss-coat") of adhesive binder to laminate the pre-manufactured slab foam sandwich. The resulting product can have increased dimensional stability, better tuft-bind and more flexibility.
The carpet can be manufactured as tiles or in rolls for wall-to-wall installation. However, the invention finds its greatest benefit in wall-to-wall installation where the dimensional stability of long runs of carpet and the difficulties of installation are more significant problems.

Claims

A laminated carpet for attachment to a floor without a separate underpad, the carpet comprising a primary layer (1) having pile elements (3) substantially covering a first side of the primary layer and loops (11) on a lower surface, the pile elements and loops being exposed on opposite faces of the carpet, characterized in that the carpet comprises:
(i) a foam layer (7) having a first fabric covering (9) on an upper surface of the layer and a second fabric covering (11) having the exposed loops on a lower surface of the layer;

(ii) means for securing the first and second covering to the foam layer (7); and

(iii) means (13) for securing the upper surface of the first covering of the foam layer to the primary layer.
The carpet of claim 1 in which the exposed loops (11) substantially cover the lower surface of the foam layer (7).
The carpet of claim 2 in which the exposed loops of the second covering are locked into the fabric of the covering.
The carpet of claim 3 in which the second covering is a knitted fabric.
The carpet of claim 3 in which the second covering is a woven fabric.
The carpet of claim 3 in which the first covering (9) is a fabric with exposed upstanding threads.
The carpet of claim 6 in which the first covering (9) is secured to the primary layer (1) by means of an adhesive coated along substantially the entire surface of the second side of the primary layer and infiltrated into the upstanding threads of the first covering (9).
The carpet of claim 7 in which the upstanding threads of the first covering (9) are loops locked into the fabric of the covering.
The carpet of claim 2 in which the loops of the second covering (11) are locked into the foam layer (7) during setting of the foam.
The carpet of claim 9 in which the first covering (9) has exposed loops projecting upwardly from its upper surface and such loops are bound to the covering and locked by the foam layer (7) during setting of the foam.
The carpet of any of the preceeding claims in which the carpet is produced with a substantially uniform cross-section so that it can be cut and fit in place as wall-to-wall carpeting.
The carpet of claim 3 in which the fabric coverings (9, 11) are secured to the surface of the foam (7) without substantial penetration of foam into the fabric.
The carpet of claim 12 in which the foam layer (7) is a pre-manufactured slab foam.
The carpet of claim 12 or 13 in which the foam layer (7) is chemically blown.
A laminated carpet for attachment to a floor, the carpet comprising a primary layer (1) having pile elements (3) tufted into and through such layer and substantially covering a first side of the primary layer and a lower surface having exposed loops (11) on an opposite face of the carpet to that of the first side, characterized in that the carpet comprises:
(i) a foam layer (7) having a first fabric covering (9) having exposed threads outstanding from the upper surface of such layer and a second fabric covering having the exposed loops on the lower surface of such layer; and

(ii) adhesive means (13) for securing the first fabric covering of the foam layer to the primary layer so that the exposed threads of the upper surface of the first covering and the tufts extending through the primary layer are sealed together.
The carpet of claim 15 in which the loops (11) are locked into the fabric of the second covering.
The carpet of claim 16 in which the second covering is adhered to the surface of the foam layer (7) without substantial penetration of foam into the second covering.
The carpet of claim 16 or 17 in wich the first covering (9) is adhered to the surface of the foam layer (7) without substantial penetration of foam into the first covering.
A method of making a laminated carpet comprising the steps of:
(i) manufacturing a foam sandwich having a foam layer (7) in the middle and two outer fabric coverings (9, 11) at least one of which coverings has loops on substantially the whole of its surface;

(ii) manufacturing a carpet pile layer, having exposed carpet pile (3) on one surface;

(iii) securing the foam sandwich to the pile layer so that the carpet pile and the loops are exposed on opposite faces of the carpet.
The method of claim 19 comprising the additional step of first setting the foam (7) before securing the coverings so as to prevent substantial penetration of the foam into the fabric coverings.