Tufted pile fabric and method of making and installing the same

A tufted pile fabric for use indoors or outdoors as a substantially permanent floor covering. The tufted pile fabric is made entirely from man-made or synthetic materials and includes a synthetic plastic primary backing, and a synthetic plastic secondary backing, laminated together by a hot melt adhesive to form a relatively rigid impervious sheet. The structure is then provided with a plurality of perforations through the substantially impervious sheet comprising the secondary backing, the hot melt adhesive and the primary backing to give the fabric a softer hand and breathability. The tufted pile fabric may then be adhesively secured to a floor structure by a water based adhesive, inert to the primary and secondary backings and hot melt adhesive, with the water evaporating through the perforations to set the adhesive and thereby avoid puckers and edge rippling due to unbonding the pile fabric from the floor structure.

The present invention relates to an improved tufted pile fabric for use 
indoors or outdoors as a substantially permanent floor covering. 
Additionally, the present invention relates to an improved method for 
making a tufted pile fabric and installing the same on a floor structure, 
as well as to a substantially permanent floor covering. 
BACKGROUND OF THE INVENTION 
In recent years, tufted pile fabrics utilizing primary and secondary 
backings made from synthetic plastic materials have been developed for use 
indoors and outdoors. These carpets have utilized synthetic plastic 
primary and secondary backings in order to provide stability to the carpet 
structure and to eliminate the problems encountered previously by carpets 
which have been made from natural fibers. Carpets made from natural fibers 
are subject to shrinking and rotting in abnormal weather conditions and 
when liquids are spilled thereon. Additionally, such carpets are subject 
to excessive staining and require frequent removal and cleaning. 
In U.S. Pat. No. 3,110,905 issued Nov. 19, 1963 to Rhodes and U.S. Pat. No. 
3,336,178 issued Aug. 15, 1976 to Levitch, and both assigned to the same 
assignee as the instant application, namely, Burlington Industries, Inc., 
there are disclosed tufted pile fabrics utilizing synthetic plastic 
backings and pile yarn also made from synthetic plastic or man-made 
fibers. While the tufted pile fabric disclosed in these two patents have 
been commercially successful for installations wherein the floor covering 
is subjected to rotting conditions, moisture conditions from rain or 
spillage of liquids, they have not been completely satisfactory when used 
in situations wherein the carpeting is to be substantially permanently 
installed by adhesively securing the same to a floor structure, 
particularly when the primary and secondary backings are bonded together 
with a hot melt adhesive. With the advent of the use of hot melt adhesives 
and the application of such technology to the disclosures in these two 
patents and particularly to the disclosure in Levitch, the resulting 
tufted pile fabric provided greatly improved adhesion between the 
synthetic primary and secondary backings, effectively preventing 
separation of the primary and the carpet face from the secondary, when the 
secondary is bonded to a floor structure. Additionally, the hot melt 
adhesive greatly improves pile bind, effectively preventing removal of 
carpet tufts from the carpet face by pulling or snagging. However, a 
carpet with a hot melt bonded primary and secondary backing also exhibits 
a very firm hand which can make the fabric too stiff for practical 
installation. More serious however is the fact that the hot melt adhesive 
combines with the synthetic primary and secondary backings to form a 
substantially impervious sheet, a factor which has effectively prevented 
satisfactory water based adhesive installation of such carpets on floor 
structures because of lack of complete drying and subsequent unbonding or 
puckering of the undried areas. Water based adhesives are desired for such 
installations because the adhesive does not dry immediately, thus 
permitting flexibility and adjustment during carpet installation. Thus, 
when such carpeting is adhesively bonded to a floor structure by a water 
based adhesive, it will gradually unbond and display ripples on the edges 
and pockets or bulges in various places throughout the carpet apparently 
because the use of the hot melt adhesive for providing the bonding between 
the primary and secondary backing and for anchoring the tufts to the 
primary backing, also eliminates the breathability of the carpet to an 
extent sufficient to prevent adequate drying or setting of the water based 
adhesive in a practical time following installation. 
PRIOR ART 
Prior art on this subject is represented by the following patents which 
disclose various textile fabrics suitable for carpeting as well as means 
for perforation of sheet material: 
______________________________________ 
Number Name Date 
______________________________________ 
2,46,040 Guild June 17, 1941 
2,388,069 Meaker et al October 30, 1945 
2,515,847 Winkler July 18, 1950 
3,137,611 Krolik, Jr. June 16, 1964 
3,157,557 Palmer November 17, 1964 
3,542,632 Eickhoff November 24, 1970 
______________________________________ 
In one of the disclosures of the above listed prior art, it will be noted 
that there is a teaching of a laminated pile fabric structure having 
perforations therethrough. However, in such disclosure, the carpeting 
which is made of natural fibers was attached to a laminated backing 
structure made of layers of loosely matted fibers after the backing 
structure had been perforated. Such a carpeting did not contemplate the 
problems involved when using synthetic plastic backings laminated or 
bonded together by hot melt adhesives which when set provide an impervious 
relatively rigid sheet therebetween. In another disclosure of the above 
listed patents, there is a teaching of fibrillating a woven fabric, such 
as a backing similar to the backings of the aforementioned Rhodes and 
Levitch patents, the purpose of the fibrillation being to produce a ribbon 
yarn fabric which is more similar to fabric woven of natural fibers. The 
fibrillation is provided to the backing prior to forming of the laminated 
structure so as to provide excellent locking characteristics between the 
flat ribbon-like warp and filling yarns. Other disclosures of the above 
listed patents relate to surfacing materials with perforations extending 
therethrough for the purpose of drainage when such materials are utilized 
as artificial sods or the like. 
BRIEF SUMMARY OF THE INVENTION 
In its broadest aspect, the present invention relates to an improvement in 
a wholly synthetic tufted pile fabric for use as a floor covering either 
indoors or outdoors. In more detail, the tufted pile fabric includes a 
synthetic plastic primary backing of substantially uniform thickness 
having a series of pile projections extending therethrough from one face 
thereof, a synthetic plastic secondary backing of substantially uniform 
thickness and means including a hot melt adhesive for securing the 
secondary backing to the other face of the primary backing and for 
anchoring the series of pile projections to the primary backing. The hot 
melt adhesive provides a substantially impervious sheet between and in 
combination with the primary and secondary backings. A plurality of 
perforations are provided which extend completely through the secondary 
backing, the hot melt adhesive, and the primary backing so that the 
resultant tufted textile fabric will have a softer hand and breathability, 
making this carpet very suitable for substantially permanent bonding 
installation on a floor structure by use of a water based adhesive. 
Additionally, the present invention contemplates a method of making such a 
tufted pile fabric having a softer hand, and breathability, and which is 
capable of being adhesively secured to a floor structure by a water based 
adhesive. Typically, the method comprises the steps of tufting a series of 
pile projections through a synthetic plastic primary backing such that 
they extend through the primary backing and outwardly from the face 
thereof, and then heating a hot melt adhesive until it is liquefied and 
tacky and then applying the liquefied hot melt adhesive to the back of the 
primary backing and substantially immediately pressing a synthetic plastic 
secondary backing onto the back of the primary backing to form a laminated 
structure. The hot melt adhesive sets to form a substantially impervious 
sheet bonding the secondary backing to the primary backing and anchoring 
the pile projections to the primary backing. This relatively rigid 
laminated structure is then fairly uniformly pierced from the secondary 
backing side at a plurality of places thereon to provide a plurality of 
perforations extending through the secondary backing, the hot melt 
adhesive and the primary backing, thus giving the resulting structure a 
substantially softer hand than the unperforated structure, and making the 
same breathable. 
Ancillary to the above, the present invention contemplates providing a 
substantially permanent floor covering for a floor structure by adhesively 
securing such perforated tufted pile fabric to the floor structure by a 
water based installation adhesive, the water of the water based 
installation adhesive substantially completely and uniformly evaporating 
through the perforations to cause the installation adhesive to set within 
a desired time frame following installation, usually overnight. The water 
based installation adhesive is inert with respect to the synthetic plastic 
primary and secondary backings, as well as the hot melt adhesive and thus 
the dimensional stability of the tufted textile fabric is not affected 
after installation, and yet the bond to the floor structure is strong and 
substantially permanent. 
A further feature of the present invention is to provide a tufted fabric 
structure which has dimensional stability despite changes in atmospheric 
conditions and, thus, does not shrink and yet the fabric structure has a 
relatively soft hand and is breathable, permitting drying of the 
installation adhesive, whereby it may be substantially permanently 
installed without subsequent unbonding from the floor structure, resulting 
in the formation of pockets, bulges, edge rippling and puckering which is 
believed due to nonuniform drying of the water based adhesive. The 
breathability provides the necessary porosity to the tufted textile fabric 
to permit substantially uniform drying and setting of the installation 
adhesive in a practical short time period following installation. 
These and other features, advantages, and objects of the present invention 
will become more apparent in the more detailed description of the 
invention which follows and in that description, reference will be made to 
the accompanying drawings as briefly described below.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to the drawings wherein like characters or reference numerals 
represent like or similar parts, there is disclosed in FIG. 1 a wholly 
synthetic tufted pile fabric suitable for installation as a floor covering 
for a substantially permanent installation either indoors or outdoors on a 
floor structure. In more detail, the tufted pile fabric, which is 
generally designated at 10, includes a plurality of pile projections 12 
which may be either cut or uncut. The pile projections 12 are shown looped 
rather than cut in FIG. 1 and since the tufted pile fabric 10 is primarily 
intended for use in situations where the floor covering is substantially 
permanently installed and would be subjected to fungus and mildew and 
other conditions which might cause rotting, shrinking and/or staining, the 
pile projections are made from man-made synthetic plastic fibers, examples 
of such fibers being made from polyamides such as nylon, polyolefins such 
as polyethylene and polypropylene, polyesters and copolymers thereof, 
polymerized acrylic and modacrylic materials, polyvinyl chloride and 
polyvinylidine chloride and like materials, as well as cellulose acetate 
and triacetate or the like, or mixtures of such plastic materials. The 
pile projections are inserted through a primary backing generally 
designated at 14 by a tufting machine (not shown) as is conventional in 
the art, which includes a series of oscillating needles arranged to carry 
the pile yarns from the back of the primary backing 14 through the same 
and extending from the face. To prevent the undesired pulling out of the 
pile projections and also to provide a firmer base for the fabric and to 
give dimensional stability, a secondary backing generally designated at 16 
is adhesively secured by the adhesive layer 18 to the primary backing, 
thus anchoring the pile yarn 12 and the stitch projections 20 thereof as a 
unitary structure. The provision of the secondary backing for a tufted 
pile fabric has been common for some time and initially materials such as 
jute, sponge and foam rubber layers, open mesh scrim and the like have 
been tried with varying degrees of success along with backsizing materials 
such as sponge and rubber lattices have been used but these materials 
frequently deteriorated. More recently, woven synthetic secondary backings 
such as those disclosed in the aforementioned U.S. Pat. No. 3,336,178 to 
Levitch have been used, these being made in accordance with the 
aforementioned U.S. Pat. No. 3,110,905 to Rhodes. Such backings have been 
found desirable because they are wholly synthetic and of uniform quality 
and thickness, and enable the making of more uniform carpet constructions 
having good dimensional stability and good physical properties. For the 
purpose of this disclosure, the Rhodes U.S. Pat. No. 3,110,905 and the 
Levitch U.S. Pat. No. 3,336,178 are incorporated herein by reference. 
As disclosed in the aforementioned Rhodes patent and Levitch patent, woven 
backing materials formed of flat ribbon-like strands or yarns made from a 
synthetic material, typically a polyolefin or one of the other fiber 
forming materials described above, provide a very satisfactory primary 
and/or secondary backing which is substantially closely woven and 
non-foraminous. 
In the present invention, in order to securely join the primary and 
secondary backings together, and to securely lock the tuft stitches in 
place, and to improve dimensional stability of the tufted pile fabric to 
make it suitable for use as a substantially permanent floor covering, it 
is preferred that the secondary backing should be secured to the primary 
backing by a hot melt adhesive since the hot melt adhesive sets firmly, 
resists degradation, and substantially permanently combines the secondary 
backing 16 and the primary backing 14. The sheet of hot melt adhesive 18 
also securely anchors the stitches 20 of the pile projections 12. However, 
such sheet 18 of hot melt adhesive suffers a disadvantage because it is 
impervious and results in a tufted pile fabric structure having a 
relatively hard and inflexible hand with no breathability. This hard hand 
makes the hot melt bonded tufted pile fabric structure difficult to 
install as a substantially permanent floor covering because of its 
inflexibility and its lack of porosity, preventing the installation 
adhesive from setting in a reasonable time. These two factors gradually 
cause the floor covering to display ripples on the edges and pockets or 
bulges in various places throughout. The stiffness tends to make the 
fabric move or rise and unbond from the floor structure in places where 
the installation adhesive does not dry sufficiently quickly and uniformly. 
Nevertheless, the hot melt material is desired because it resists 
deterioration from foreign substances, and provides excellent adhesive 
qualities as discussed above. 
The use of a water based installation adhesive is preferred because of 
desirable properties. These include low fire danger, being inert to the 
tufted carpet construction materials, and good drying properties. By the 
latter is meant that the installation adhesive will dry slowly enough to 
permit adjustment during installation (in contrast to a "contact" cement), 
but yet will become set within an hour, e.g. 15-20 minutes, and will dry 
or cure essentially completely overnight. 
To eliminate the aforementioned disadvantages and yet still provide a 
substantially permanent floor covering having the advantages of 
dimensional stability and wearability when installed with the further 
advantage to resist stains, according to the present invention the tufted 
pile fabric 10 is perforated in a plurality of places from its secondary 
backing side, the perforations 22 extending through the secondary backing 
16, the impervious sheet of hot melt adhesive 18 and the primary backing 
14. The perforations may be formed in the tufted pile fabric 10 by use of 
a tufting machine designated generally at 24 in FIG. 2, the tufting 
machine being modified to have its needle bar 26 provided with a reduced 
stroke or with needles 28 of a reduced length so that the needles just 
penetrate through to the outer surface of primary backing 14 and do not 
penetrate far enough to interfere with the pile projections 12. Of course, 
rather than using a modified tufting machine 24, a heavy duty roll 
provided with a plurality of spikes projecting from its surface may be 
used so long as the spikes have the correct diameter, length and spacing 
and so long as a series of hold-down rolls are provided to press the 
tufted pile fabric 10 down onto the spikes and thus form the perforations 
22. It will be appreciated that if a roll type perforation apparatus is 
used instead of a modified tufting machine 24, the deflection of the roll 
must be eliminated so that perforations of uniform depth and size are 
effected across the width of the tufted pile fabric, to provide 
substantially uniform breathability to the thus perforated fabric. 
Referring back to the hot melt adhesive which is utilized to adhesively 
secure the secondary backing 16 to the primary backing 14 and anchoring 
the pile projections 12 therein, it has been discovered that very 
satisfactory results can be obtained by a hot melt adhesive comprising a 
mixture of three components such as (1) a Picco resin Part 20 made by 
Hercules, Inc., the resin being an aliphatic aromatic thermoplastic 
hydrocarbon resin, (2) Elvax pellets Part 55 manufactured by the DuPont 
Company which is an ethylene-vinyl acetate copolymer and (3) a filler of 
alumina trihydrate or calcium carbonate. A mixture of 48 percent (14400 
pounds) of the alkylated aromatic thermoplastic hydrocarbon resin, 22 
percent (6600 pounds) of the ethylene-vinyl acetate copolymer and 30 
percent (9000 pounds) of alumna trihydrate were mixed and heated to 
liquefy the same and then while in a liquefied state, the mixture was 
applied to either the primary backing or the secondary backing by a doctor 
blade or the like and the two backings were then pressed together until 
the hot melt adhesive had set as an impervious sheet of the same. 
Once the hot melt adhesive had set to form the laminated structure of the 
tufted pile fabric 10, the perforations 22 were then made in the same by 
utilizing needles of the tufting machine 24 which penetrated through the 
structure just through and to the primary backing 14. The needles were 
0.064 inches thick and 0.130 inches wide and the tufted pile fabric was 
passed through the tufting machine 24 with the secondary backing 16 facing 
the needles at a rate of 45 feet per minute with the number of strokes of 
the needle bar being 800 per minute. The width-wise spacing of the needles 
on the needle board was three-eighths of an inch and the length-wise 
spacing between the holes formed by the needles 28 was five-eighths of an 
inch. This perforating procedure is preferred since it fairly accurately 
controls the size, depth and spacing of the holes so produced, and avoids 
damage to the pile tufts themselves. This procedure resulted in tufted 
pile fabric 10 having a sufficiently soft hand to permit ease of 
installation and the installation was further enhanced as the drying rate 
of the water based installation adhesive appeared to proceed 
satisfactorily with evaporation of the water vehicle through the holes 
provided by the perforations, since this installation did not result in 
edge ripples or pockets which had plagued adhesive installations of 
synthetic nonperforated carpets heretofore. 
In installing the tufted pile fabric 10 on a floor structure 30 as shown in 
FIG. 3, a water based adhesive inert to the primary backing 14, secondary 
backing 16, hot melt adhesive sheet 18 and pile projections 12 was used. 
In this respect, a preferred installation adhesive is supplied by the 
Bordon Chemical Company under the tradename PLACCO LA6252, which is 
believed to be a water based mixture of a synthetic latex and a tackifying 
resin that is thickened to a trowelable viscosity. Other water based 
installation adhesives are well known in the art. The water based adhesive 
32 is applied to the floor structure 30 by trowels or the like and the 
tufted pile fabric is then rolled or placed onto the water based adhesive 
32 and floor structure 30. The water vehicle of the water based adhesive 
evaporates through the holes formed by perforations 22, thus, permitting 
the adhesive to dry out and develop its ultimate strength and tackiness in 
a reasonable time. The floor structure may be a masonry or concrete floor 
structure such as found on patios, outside walks or floors, or inside 
floors of commercial and industrial buildings, as well as in homes, or it 
may be wood or other suitable subfloor materials where wood or another 
material is used either inside or outside as a floor structure. 
Referring now to FIGS. 4 and 5, there is disclosed a modified synthetic 
plastic backing material which is preferably used as the secondary backing 
16' of the tufted pile fabric 10 although it could be used as a primary 
backing. In this respect, the woven backing 16' includes synthetic plastic 
twisted yarns or strands 34 used as the warp and flat ribbon-like yarns or 
strands 36 used as the weft, the ribbon-like yarns or stands 36 providing 
the backing material 16 with the characteristics of being substantially 
impervious or non-foraminous. By utilizing the twisted yarns or strands 
34, the resulting backing material 16' has added strength in its warp-wise 
direction and when this backing material is laminated pg,20 to the 
primary backing material 14 of the textile pile fabric 10, the yarns 34 
are oriented in a weft-wise direction with respect to the stitches 18 of 
the pile projections 12 to thus add to the weft-wise dimensional stability 
of the overall structure. 
It is also contemplated that the secondary backing, and even the primary 
backing, may include spun or multifilament type yarns, particularly in the 
filling of certain secondary backing constructions, to increase physical 
adhesion by the hot melt resin or the installation adhesive. In some 
instances, a synthetic nonwoven material such as DuPont's "Typar" may also 
be used as the primary backing material. 
The perforation size and spacing mentioned above may be changed if desired. 
An increase in needle bar speed at constant or lower tufted fabric feed 
will increase the concentration of perforations, while a decrease in 
needle bar speed or a higher tufted fabric feed will result in a lower 
concentration of perforations. 
As mentioned above, the water based installation adhesive 32 is preferably 
inert to the materials used in the primary and secondary backings and 
tufting yarns as well as the hot melt adhesive. It should also be 
mentioned that the hot melt adhesive likewise is preferably inert to the 
other materials which make up the tufted pile fabric. 
The terminology used throughout the specification is for the purpose of 
description and not limitation, the scope of the invention being defined 
in the claims.