CA1130188A - Tufted pile floor covering - Google Patents

Abstract

TUFTED PILE FLOOR COVERING

Abstract Of The Invention A tufted pile floor covering formed of an elastomeric base and a pile composite adhered thereto. The pile composite is formed of a primary pile backing through which loops of the piling project on one side with a connecting portions underlying the backing. The piling is a fibrous material such as polyester fiber coated with a material chemically similar to the base material. In adhering the piling composite to the elastomeric base, the connecting portions are embedded in and adhered to the base. A method is provided for making the floor covering which comprises floating the pile composite onto a pool of liquid plastisol of the base material to submerge the connecting portions of the piling therein and subsequently solvating the base material to mechanically embed and fuse the pile composite thereto.

Description

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Back ~o~uld ~nd S~lmmary Of The Invention The present invention relates to an improved f]oor covering material which is characterized by three distinct layers. The base layer, or secondary backing, is a resilient vinyl halide polymer or copolymer, preferably derived from a plastisol. An intermediate layer or primary pile backing is provided and is convenientl~ formed of a polyolein material. The third ana upper layer is tufted into the primary pile backing layer preferably as a continuous looped pile ~7ith loops projecting from the upper side thereof and connecting portions underlying the backing. According to the present invention, the piling material is a vinyl chloride polymer or copolymer coated fibrous material. In fabricating the floor covering of the present invention, the connecting por~ions of the tuft~d piling `
which extend through the pile backing are embedded in and fused with the upper portion of the bottom layer One type of floor covering heretofore available utilizes extruded elongated plasticized polyvinyl chloride filaments which are extruded onto a foam backing. These filaments are~
adhered to the backing and to each other in a random manner ta form a nonwoven, nonIooped randomly interlacea or tangled piling on the foam base. The piling of this type of floor~
covering has a tendency to trap dirt.
The floor coverings of the present invention are characterized by a tufted piling supported on a primary pile ~- ~ -~
backing and having a bottom or connecting portion of the piling underlying the bac~ing embedded in the base material. Such a ~loor covering is easy to clean with a stream of water from a hose and have excellent wear characteristics. The piling which I ~
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is a fiber reinforced polyvinyl halide thread is also ef~ective in removinc snow, slush, dirt, etc. from shoes. Still further, ;the floor coverings hereof are substantially unafEected by exposure to moisture, deicing compositions and granular foreicn materials. The improveci floor coverings are also amenable to manufacture by a continuous process enabling the production o~
longer and wider strips than the forementioned covering.
i The floor covering materials of the present invention are particularly useful as floor coverings for public walkways and ,doorways subject to contact with sno~, ice, slush, and thawing 7Ichemicals. They may be used indoors as well as outside.
¦ The term "PVC" and the term "polyvinyl chloride" as used herein will be understood as equivalent and ~eneric to -homopolymers and copolymers of polyvinyl chloride.
I Briefly, the present invention is a floor covering hav;ng ¦an elastomeric base, or secondary backing, and a fabric suppor~ed piling of elas~omer coated threads adhered to the upper surface of the base. The piling comprises a dense array of threads extending from the fabric to form an upper exposed ,pile surface, preferably a looped pile surace, and projecting downward through the fabric for embedment in and fusion with the elastomerlc base. Chemically, the elastomeric base is a polyvinyl chloride homopolymer or copolymer. The threads forming the piling have a coating of an ela5tomeric polyvinyl -chloride homopolymer or copolymer thereon which is compatible iwith that from which the~elastomeric ba5e is formed. The ¦Ifabric into whiCh the piling iS supported, is desirably a ,Ichemically dissimilar synthetic or natural fiber, and is a oven r nonwoven Eabric into whiCh the p~ling is tuEted.

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~; The invention also contemplates a method of ~naking a surface covering material by embedding and fusing to a ' plastisol derived PVC elastomeric base a fabric supported piling of PVC coated threads.

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I, Other objects and advantages of the present invention will i be apparent and better understood from the following ~
! description and the accompanying drawings in which: ~ ;
j' Figure 1 is a fragmentary partially cut-away perspective ¦l view of a floor covering in accordance with the present inventionO ~ i Figure 2 is a cross sectional view on an enlarged scale of the floor covering shown in Figure 1 as it appea~s in the plane ¦'' indicated by the line 2-2 in Figure 1.
t Figure 3 is a cross sectional view on an enlarged scale showing a tùfted piling and primary pile backing with ~he underside of the piling threads embedded in the secondary base. ` ~-~
Figure 4 is a cross sectional view on a much enlarged si_ale ¦ of a piling thread in accordance with the present invention. ~ ~
¦ Figure 5 is a diagrammatic and schematic representation of ~ ~ ;
¦ a process and apparatus by which the floor c~vering of the ¦ present invention is groduced. ~;

Referring now more particularly to Figures l and 2 there is' shown in perspective and in section a floor coverîng material ~ ;
in accordance with the~present invention. The floor covering ¦ inc udes a nonloamcd or solid elastomeric vinyl hal-de pol~er ~ 4 ~
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secondary backin~ layer 10 and a ]ooped tuf~ed piling 12 secured thereto. The looped piling is supportea on a primary pile backing 14. As shown in Fig. 1, the pile surface is composed of rows 17 of loops 15, eac:h row being a single continuous thread tufted into the pile backin~ 14 and having discrete loops 15 projecting from the upper side of the backing-14. The underside of the secondary backing material 10 is desirably textured or roughened as indicated by the , indentations 16 to confer a nonslip characteristic to the floor ¦ covering material. Although the looped tufted piling is Il preferred, the projecting loops on the side to be exposed may ¦~ be cut if desired. -! In accordance with the present invention, the piling 12 is j fused to the layer 10. Figure 3 shows in detail the fusion of ¦I the piiing 12 -~hich extends through to ~he under$iae of the --, primary pile-backing ld and into embedded relation with the secondary backing or base layer 10.
The primary backing 14 is a woven backing conveniently ¦
formed o~ flat strands of a synthetic resinous material such as a polyolefin, e.g. polypropylene. Instead of a synthetic -material, the primary backing 14 may be formed of natural fibers, e.g. jute, hemp, or the like. Optionally, the primary pile backing 14 may be nonwoven. ~- .
¦ The piling 12 is formed of threads oE polyvinyl haliae ~ ~
I coated fibrous material, and particularly polyvinyl chloride `
i coated bundles of polyester filaments of strands such as shown !` on a greatly enlarged~scale in Figure 4. Such coated ~hreads are commercially available. The coated fibrous material to produce the piling material 12 may be producea by known . ' ' ' `

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methods. Homopolymers of vinyl halide, e.g., vinyl chloride, and copolymers thereof ~ith a vinyl ester, e.g., vinyl acetate, may be used in forming the coated threads. One particular]y adva~tagous method of coating is crosshead extruding a polyvinyl chloride coating onto a bundle of strands to form a 1 thread having a sheath coating that does not penetrate ¦~ internally of the ~ibrous core of the thread as shown in Fig.
i 4. Alternatively dipping of the strands into a PVC solution or `
, plastisol may be used to apply the coating to the thr~ads.
¦~ The preferred fibrous material from which the threads ~re t formed is a polyester fiber 18 made of a bundle of stranas, ;
e.g. 500 to 1000 denier strands per buDdle. The bundle of strands has a PVC coating 20 there~n from 1 to 10 mils thick.
~l Instead of polyester (polyethylene terephthalate~ fiber, other ¦I synthetic filaments or stranas may be used, e.g. n~lon, glass, rayon, metal_wire, cellulose acetate, etc.
¦ As shown in Figure 4, a cross section of a preferred pile thread 12 is composed of a core of a plurality of polyester ~
fiber filaments in a bundle, and encased in a relatively thin -¦ (e.g. 1 to 10 mils) resinous sheath 20 comprising polyvinyl ~ ~-chloride (PVC). Although the cross section of the thread illustrates a wholly external coating or sheath of PVC, which~ -is preferred, it will be understood that the coatin~ material~
j may permeate the filaments forming the core of the thread. ~he ¦ core desirably has a tensile strength greater than the po]yvinyl halide coating, and thus serves as a reinforcing ` element for the coating material.
i The thread coating formulations are well known and may contain finely divided (e.g. -200 mesh) said particulate material. Thu_, pigments,~fi1lers, extendors, as well as other 6 ~ ~ ~
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particulate solids may be dispersed by known means into the thread coating materials. It is contemplated, for example, to disperse ground glass or sand having a suitable particle size in the vinyl halide composition which is applied to the fiber , bundles to confer a nonslip surface to the projectin~ piling j, threads as an added safety feature. Instead of sand or ground 1' glass, any other abrasive material may be used. From 5% to 20%
, by weight of solid particulate material may be dispersed in the I thread coatings to provide color, inexpensive extenaing filler, nonslip qualities, reflective properties, fire retardant i properties, etc.
Tu~ting of the PVC coated fibers throu~h the primary pile backing 14 to form the pile/primary backing composite may be ~, accomplished by known procedure on known equipment.
i~ Figure ~ shows in diagrammatic and schematic orm an -ij apparatus for- producing the floor coverings of the present invention. The apparatus includes a flexible bel~ 22 moving in the dirèction indicated by the arrow 24. A supply o~ polyvinyl chloride plastisol is contained in the vessel 26, and deposited -~
on the belt 22 by any convenient process, such as curtain ¦ coating. As is well known, the plastisol compositi~ns are ~ ~
i liquid and are dispersions of dispersion-size polyvinyl ~ -chloride particles in a plasticizer or solvent-for ~he i polymer. These plastisols are incomplete solutions and are~
l stable dispersions at ordinary temperatures. To complete the~
solution and the conversion of the polymer to a solid elastomeric material, heat is required, ana to effect ~ ;; 1 "solvation" an oven 28 is provided. "Solvatlon" proceeds in ~ ;

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two stages - "gel],ation", which is partial solvation, and ` complete solvation to yield a hornogeneous plasticized , elastomeric polyvinyl chloride base sheet 10.
In order to regulate the thickness of the secondary backing 10, there is provided a doctor blade 30 which spans the belt Il and which functions to control the thickness of the plastisol ! layer from which the secondary backing 10 is,formed. For most ,} purposes, the final thickness of the secondary backing 10 will i be from 25-125 mils, e.g., 75 mils. The previously tufted, ~, piling/primary backing composite is rolled on a supply reel 32 I! supported above the belt 22, and fed from the supply reel 32 ¦1 onto a guide plate 34 disposed at a suitable angle,with respec~
to the belt 2?, e.g. a 45 angle. The leading end 36 of the ! tufted piling composite 12 is brought into contact with the ¦ liquid pool of plastisol adjacent the discharge end 38 o~ the ~ ,~
plate 34 where it sinks into the liquid plastisol to the point -where the backing 14 virtually floats on the top o~ the sur~ace of the li~uid plastisol and is carried along witb the pool of I liquid plastisol. In such a condition, the conpecting portions ¦ 15~of the piling ~Fig. 3~ which underlie the primary pile : ;
¦ backing 14 are submerged in the liquid plastisol from which the ¦ backing 10 will be formed during tbe thermal solvating ¦ process. Thus, the liquid plastisol completely surrounas thè
¦ lower portion polyvinyl halide coated threads 12 that project ~hrough the primary backing 14. The composite then enters a I, solvating oven 28 to solidify the base 10 and fuse the vinyl ¦~' coating on th,e threads 12 into the base 10. Inasmuch as the . . ~ .
; I plasticizer dispersing medium o the plastisol is compatible ;
with the thermoplastic polyvinyl chloride ooatln~ of the piliAg 8 ~
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threads 12, under the influence of the solvatin~ heating oven , 28, the piling 12 and the base material 10 become fused ; together as the base 10 is ~elled and solidif~ed in the solvating process. As the completed floor covering material ; leaves the conveyor belt 22, it is wound upon a take-up reel 40. Sufficient length may be provided for spontaneous cooling of the solvated plastisol material Oll the belt, or forced cooling means may be provided as desired. `
,' The resulting material`may be then cut to desired shapes or l~ sizes.
I The floor covering materials of the present invention are ¦ characterized by the fact that the pil-ing material is extremely strongly adhered to the ba5e layer 10. Thusr fraying or piling separation is minimized. Because of the nature of the surface of the polyvinyl halide coating and the polyvinyl halide base layer 10, the-floor covering materials of the present invention are impermeable to water and easily cleaned. The nature o~ the looped piling enables the accummulation o~ snow, mua, etc. ~rom the feet of passers by and its collection ~ithin the loops of the piling. As indicated above, it is readily flushed out with a stream of wster and removed from the floor covering materisl ;
as needed.
In carrying out the present invention, the use of PVC
! polymers and copolymers ~or forming the thread coatin~s as well ~`~
i! as the secondary backiny is pre~erred because of the relative availability and low cost of these materials in adaition to other desired properties. An important feature of the present invention is that the secondary backing material 10 and the coat ng 20 of ths pile thr~sds 12 should be of c1Osely sioil~r . ` `~ ~.

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chemical nature, preferably being formed of the same or closely similar homopolymer or copolymer compositions. Thus, the preferred embodiment provides a polyvinyl chloride coating 20 for the fibers, and a po]yvinyl chloride for the base layer or secondary backing 10. Instead of polyvinyl chloride, other polyvinyl halides, e.g. polyvinyl 1uoride, polyvinyl bromide may be used. Copolymers of vinyl halides and vinyl acetate may ~e used. Thus, a polyvinyl chloride-vinyl aceta~e copolymer (2~ to 10~ vinyl acetate) may be used in accordance w~th the present invention.
As indicated above, the preferred primary backing material for the piling is a polyolefin material, e.g. polypropylene.
This material is normally supplied in woven sheets to provide a primary pile backing material into which the piling is tu~ted by known means. The polyolefin ma.erial is unaffected by the plasticizer forming the dispersion medium for the vinyl halide resin plastisol. Although the primary backing material may itsel~ ultimately become adhered to the top surface of the solvated base material lOr it is not essential to the production of satisfactory floor covering materials of ~he present invention. It~is desirable that the primary backin~
"float" on the top surface of the li~uid plastisol as it ~¦
receives the tufted piling and primary backing composite from the supply roll 32. Any woven pile fabric material may be used for the primary backing 14 in accordance with the present invention. It may be formed from threads of natural or synthetic fibers. These are woven by known means to provide a pile backing. The pile backing may also be a relatively thin~
flexible sheet 5 t:o 40 mils thick, e~g., rubber or urethane : ' ''`':

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~L13'1~8~ , foam. It is desirable that the pile backing mater;al be 1~ unaffected by the plasticizer and any diluent or solvent which i may be present in the plastis~l composition from which the ,` secondary backing 10 is formed.
i; As indicated, the secondary bac~ing or base layer 10 is ¦~ preferably formed from a plastisol. Plastisols of h~mopolymers and cop~lymers of polyvinyl chloride and their formulation are ~well known. In general, the plastisol is a dispersio~ 40% to 70% by weight, preferably 50%-60% by weight, of fine particle 250 micron) dispersion size PVC in a plastic;zer as a ! dispersion medium. The rigidity or resilience o~ the solvated I plastisol, or fused organisol is determined by the I concentration of plasticizer, or solvent as the case may be.
¦ Within the range stated above, the fully solvated PVC resins I are flexible and resilientr From 0.1 to 4.0~ b~ weight o~ a ~1 ¦ light and heat stabilizer, e.g. lead carbonate, dibasic lead `
jl phosphate or barium-cadmium stabilizer is usually included in -I the plastisol formulation. Suita~le plasticizer meaia ~or --¦ formulating plastisols of PVC homopolymer~ and copolymers ¦ incluae dioctyl phthalate, dibutyl phthaLate, and di-2-ethylhexylphthalate,trioctyl phosphate and mixtures of various plasticizers. These are known, commercially available materials. -~ These plastisol formulations may also include from 5~ to ¦l 15% by weight of fillers and extenders in finely divided form , (e.g., -200 mesh), e.g. barytes, calcium carbonate, barium sulfate, silica, diatomaceous earth, fullers earth, attapulgus cla~ ground glass, sand, etc. Fr~guently a small anount ' ' ~ ` 11 ' : :'.
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(0.05% to .5~) of a lubricant (internal or external) e.g. wax, calcium stearate, lead stearate, or the like is included in the formulation.
Specific examples of pigments which may be included in both the plastisol and thread coating formulations, are carbon black, cadmium sulfide~ zinc oxide, titanium dioxide, barium chromate, lead chromate, PbCrO4 PbO, cobalt aluminate, chrome oxide, etc., or mixtures thereof may be used in usual amounts, e.g., 0.5% to 10% by weight.
The plastisol ingredients are blended in a suitable mixer.
A typical illustrative plastisol formulation for both the pile fibers and the base is as follows:

Cadmium yellow pigment 2.0 Barytes 16.0%
PVC (homopolymer) 45.5%
Dioctyl phthalate 36.2%
Light stabilizer 0.3 Another plastisol formulation useful herein is:

Polyvinyl chloride-vinyl acetate (copolymer) 100 parts Dioctyl phthalate 30 parts Trioctyl phosphate 20 parts Dioctyl sebacate 10 parts Barium-cadmium stabilizer 3.5 parts Antimony trioxide flame retarder 5.0 parts Numerous other plastisol formulations are well known in the `~
art, commercially available, and can be used in fabricating both the coated fibers and the secondary ~acking of the floor coverings of the present invention. Such plastisols are first gelled and then fused (solvated) at temperatures generally in the range of 170 to 220C. The fusion temperature and minimum ~;
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residence time in the oven to produce a plasticized PVC
elastomeric base 10 with the PVC coated pile threads 12 fused ~ ~ -12- ~

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to and embedded in the upper surface thereof will vary with each plastisol or organisol and can be determined quite simply with the apparatus used in making t:he floor coverin~.
Residence times will be found for ntost purposes to be in ~he range of 3 to 30 minutes depending on the temperature achieved in the base, the nature of the plasticizer or mixture of plasticizers used, etc. Residence time will also vary with the thickness of the base des;red, the thicker sections requiring more residence time. A heat stabilizer is conveniently included in the pile fiber coating plastisol to aid in ~
preventing degradation of the PVC during transit through the -oven, and in use, e.g. exterior exposure to hot sun. For this purpose any known heat and/or ligh~ stabilizer may be use~ in -the usual amounts. `~ `
Although plastisols provide a convenient way of handling~ ~;
polyvinyl chloride compositions, it will be understood that the PVC solutions in a plasticizer as distinct from the plastisol form may also be used not only for coating the fibers to make the polyvinyl chloride coated threads but also for casting the ~-~`
base layèr 10. Other resinous base materials may be used, although because of chemical dissimilarity, are less desirable than the more compatible and easily handled plastisols~ Thus,~
a liquid form (e.g., solution or uncured liquid) of a urethane resin which cures to a solid or foamed condition may be cast onto the moving belt and the pile/primary backing composite applied thereto as with the plastisol and the resulting assembly cured or solidified in a suitable oven. Alsor albeit less desirably instead of casting the li~uified form of the ' I . ' ' ~ '"' ,, - - . - . ~ .

- ( 11301B8 ( base 10 onto a moving belt, the piling/primary backing composite may be inverted and placed on the moving belt and the plastisol applied to the reverse sicle and solvated in a conventional carpet oven.

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Claims (14)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A floor covering composite having a base layer for contacting a floor and a pile portion adapted to be trod upon and comprising:
a fluid impermeable, flexible polymeric base layer adapted to contact a floor surface;
an intermediate woven primary pile backing supported on the upper surface of said base layer; and a looped piling material tufted into said intermediate primary pile backing, the piling having exposed loops above said backing and piling portions projecting below said backing, the piling portions below said backing being embedded in said flexible polymeric base layer, said piling being formed from threads having a reinforcing inner fibrous core and an exterior poly(vinyl chloride) coating, said inner fibrous core having a tensile strength greater than the tensile strength of said exterior coating, said piling portions below said backing being mechanically locked with said base layer.

2. The floor covering composite as set forth in claim 1 wherein said flexible polymeric base layer and said polymeric coating on said piling are chemically com-patible and the polymeric base and coating are fused with each other to create an adherent chemical bond therebetween.

3. The floor covering composite as set forth in claim 2 wherein said flexible polymeric base layer and said polymeric coating are both vinyl chloride plastic materials.

4. The floor covering composite as set forth in claim 3 wherein said vinyl chloride plastic material for said flexible polymeric base and polymeric coating are independently selected from a group consisting of homopoly-mers of vinyl chloride, copolymers of vinyl chloride, and mixtures thereof.

5. The floor covering composite as set forth in claim 1 wherein the underside of said base layer is roughened.

6. The floor covering composite as set forth in claim 1 wherein said primary pile backing is formed of a synthetic resin.

7. The floor covering composite as set forth in claim 6 wherein said synthetic resin is polypropylene.

8. The floor covering composite as set forth in claim 1 wherein said primary pile backing is a woven pile backing.

9. The floor covering composite as set forth in claim 1 wherein said primary pile backing is nonwoven.

10. A floor covering composite having a base layer for contacting a floor and a pile portion adpated to be trod upon and comprising:

a fluid impermeable, flexible polymeric base layer adapted to contact a floor surface;
an intermediate woven primary pile backing supported on the upper surface of said base layer; and a looped piling material tufted into said intermediate primary pile backing, the piling having exposed loops above said backing and piling portions projecting below said backing, the piling portions below said backing being embedded in said flexible polymeric base layer, said piling being formed from threads having a reinforcing inner fibrous core and an exterior polymeric coating, said piling portions below said backing being mechanically locked with said base layer, said piling threads comprising a bundle of polyester fibers having a poly(vinyl chloride) coating thereon.

11. The floor covering composite as set forth in claim 10 wherein said base layer is a solvated poly(vinyl chloride) resin.

12. The floor covering composite as set forth in claim 10 wherein said base layer comprises a copolymer of vinyl chloride and vinyl acetate.

13. The floor covering composite as set forth in claim 12 wherein said base layer is foamed.

14. A floor covering composite as defined in claim 10 wherein said inner fibrous core comprises a bundle of fibers having a poly(vinyl chloride) coating thereon.