CA1112143A - Manufacture of nonwoven pile articles - Google Patents

Abstract

Abstract of the Disclosure In procedure for making nonwoven pile articles by assembling an array of cut pile fibers or yarns having free ends disposed substantially in a common plane and adhering a backing to the free ends, the step of treating the fibers or yarns with steam after assembling the array but before apply-ing the backing thereto while mechanically agitating the support structure for the array.

Description

Backgr~und of the Invention . .

This invention relates to procedures for making nonwoven pile articles, and more particularly to procedures of the type wherein an adherent backing is applied to the free ends of a pre-assemble~ array of cut pile yarns or fibers.
For convenience of expression, the term "fibers" will be used herein to refer to yarns as well as to individual discrete fibers.
It i8 known to assemble an array of substantially aligned cut pile fibers having free ends disposed substantially in a common plane, and then to apply an adherent backing to the free ends of the assembled fibers, for production of a nonwoven pile article. Examples of such procedures are described in U.S. PatentsNos. 3,499,807, 3,850,713 and 3,971,685. Pile articles produced in this way may be used as carpets or for other purposes, and offer advantages especially with respect to ease of fabrication and economy of pile fiber consumption.
In procedures of the foregoing character, pile den~ity is controlled or adjusted by performing appropriate operations on the assembled fibers prior to application of the backing. Although the aforementioned patents describe effective ways of achieving such density control, it is found that (as also in more conventionally produced pile articles) spaces may remain between adjacent fiber ends where they join the backing, so that areas of exposed backing may be i ~

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seen ln the produced plle artlcle when the plle rlbers are separated. Presence Or these exposed areas Or ~e backlng is undeslrable slnce they tend to become vlslble as the plle depth decreases through wear, imparting a threadbare appear-ance to the article.
Heretorore, complete plle artlcles comprlsing a riber plle adhered or otherwise secured to a backing have sometimes been treated with steam or hot water to alter-the physical characteristics of the plle ribers and/or ror other purposes. One errect Or such treatment is a "blooming" or apparent denslrlcation Or the ~ree upper portions Or the rlbers. The blooming errect, however, does not alter the axlal spaclng Or the rlbers nor does it extend to the riber ends whlch are anchored to the backing; hence it does n~ over-come the problem Or exposure Or areas Or the backlng between ribers and resultant threadbare appearance as the pile wears.

Summary Or the Invention The present inventlon broadly contemplates the pro-~lsbn Or proc~dure rOr maklng a nonwoven plle artlcle by assembling an array Or plle ribers having rree ends disposed substantially ln a common plane, and adhering a backing to the rree ends o~ the ribers, whereln the improvement comprises exposing the rlbers to steam arter assembly Or the array but prior to application Or the backing. The steam treatment may, or example, be perrormed by directlng ~ets Or steam through a porous moving or stationary rlrst surrace whlle maintaining the riber array disposed between the ~irst sur~ace and a second surrace rOr preventing axial dislocation Or the ribers. Al-ternatlvely, the array may be exposed to a relatively .

qulescent atmssphere Or ~team ln a steam chamber. Desirably in most lnstances, the surface or sur~aces in contact with the fibers during the steam treatment are preheated to prevent condensatlon Or molsture.
By thus treatlng the ribers with steam before appli-cation o~ the backing (rather than a~terwards, 2S in prior practice), the procedure o~ the present lnvention achleYes a riber blosming sr apparent densirication ef~ect that very ælgniricantly extends to and includes 'hose rree ends o~ the ribers which are to be adhered ts the bac}cing. As a result, when the ba¢king ls subsequently applled, the bloomed ~ree ends adherlng to lt substantlally completely csver the entire backln~ surrace, leaving llttle or no exposed area on the pile-bearing side Or the backlng. ~he pile there~ore ex-hlblt3 desis~ably unirorm apparent density, wlth no "bald spots,"
even as lt wears to a small rractlon o~ its orlginal depth.
Moreover, the treatment Or the ~ibers with steam prlor to appllcation o~ the backlng can be perrormed so as to e~rect, or to cooperate with other steps in errectin~, den-slty control Or the ribers, i.e. to achleve desired axial spaclng (and unl~ormlty Or dlstrlbutlon) o~ the ~ree-ended ~lbers wlthln thearray. Since the ribers, when sub~ected to steam in accordance wlth the lnventlon, are laterally mov-able relative to each other (rather than being anchored at one end in a baclclng), resultant blooming o~ the ~lbers can pro-duce relative lateral movement o~ the ~ibers to space them rurther apart and/or more uni~ormly in the array. When the steam ls applled ln ~ets, the agitation caused by the ~et currents a~dltionally promotes relative lateral displacement , . , of fibers for density control.
',, Further features and advantages of the invention will be apparent from the ~detailed description hereinbelow set forth,' together with'the accompanying drawings.

' Brief Descr'ipt'i'on of the Draw_n~Ls Fig. 1 is a schematic side elevational view of apparatus for forming a nonwoven pile article, illustrating the practlce of the present invention in a particular embodi-mentt Fig. 2 is a further simplified perspective view of the pile-forming apparatus and procedure of Fig. l;
Fig. 3 is an enlarged fragmentary side view illus-trating application of steam as in the embodiment of Fig. l;
Fig. 4 i9 a largely diagrammatic side elevational view of a further pile-forming system in which the procedure of the present invention may be practiced~
Fig. 5 i8 an enlarged fragmentary slde elevational view in illustration of another embodlment of the invention;
Fig. 6 is a schematic side elevational view in illu~tration of a further modified embodiment o the invention;
Fig. 7 i8 an enlarged fragmentary side elevational view in illustration of still another embodiment of the inven-tion;

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- -Fi~. 8 is a similar view illustrating a further embodiment of the inventibn;
~ ig. 9 is a schematic side elevational view of yet another system in which the present invention may be practiced;
and Fig. 10 is an enlarged fragmentary side elevational view of a further embodiment of the invention incorporating the use of vibration means.

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Detalled Descri~tlon Rererring rlrst to Flgs. 1 and 2, there ls lllus-trated in si~plirled schematlc vlew a system ~or produclng a nonwoven plle artlcle, e.~. a cut pile carpet, as generally set rorth in t~e patents cited above.
In thls system, an array 10 of cut plle ribers 11 is established on the upper run Or an endless belt 12 by a rlber delivery de~lce 14, ~or example a devlce Or any o~ the types descrlbed ln the arorement-loned patents, to which refer-ence may be made ror detalls o~ constructlon and operatlon thereor. Stated broadly, the device 14 (~lg. 2) distributes on the upper surrace Or the belt 12 a plurality Or pile unlts 15 (Fig. 1) each comprlslng a dlsc-shaped, cyllndrlcal assembly substantially all~ned cut plle ~lbers ha~ing oppo-ed rree ends and held together in laterally compressed relatlon by a surrounding sleeve 16 Or rlexible, disposable material such as polyethylene ~ilm. The unlts 15 are deposlted on the belt, as shown ln Flg. 1,, in successive rows Or plural unlts wlth the lower ~ree ends Or the rlbers Or cach unlt cnga~ing the belt sur~ac,es. Upon or prior to deposlt Or the unlts, the slee~es are stripped thererrom by sultable means (not shown), releasing the contalned ~ibers ~or expanslon o~,the unlts ~pre-rerably under the lnrluence o~ a rorce applled by appropriate meano, not shown in Flgs. '1 and 2) into an essentially con-tinuous array o~ pile ribers~ extendin~ across and along the belt upper surface.
In thlæ array, the rlbers are substantlally allgned wlth each other and are supported by the belt ln upstandlng relation thereto wlth thelr lower rree ends restlng on the belt .

surrace and their upper rree ends disposed substantially ln a common plane parallel to but spaced above the belt surrace.
The belt, whlch is trained over a drlve roller 18 and ~
rollower roller 19, advances the array 10 o~ ~lbers in the dlrection shown by arrows 20. Prererably, a second driven endless belt 22 (omitted ~rom Fig. 1 ror simplicity Or illus-tration) llghtly engages the upper free ends Or the ribers in the array as they advance, to prevent accidental displacement Or the ribers in an axial direction; as shown in Fig. 2, the lower run Or belt 22 is driven in the same direction (and at the same velocity) as the sub~acent upper run o~ belt 12.
At a locality 23 spaced rrom the device 14, and beyond belt 22, a continuous backing web 24 trained over a roller 26 comes into engagement with the upper free ends o~
the ribers Or the array 10. An adhesive substance, applied to the surrace Or web 24 ahead Or locality 23 by an applicator represented at 28, anchors the rlbers endwlse to the web to rorm a complete pile article, whlch may thereartér be sub-~ected to curing treatment ~not shown) e.g. Or a conventlonal nature.
The ~oregoing procedure, which wlll be understood to be merely exemplary o~ operatlons wlth which the present in-vention may be practlced, i9, as stated, fully descrlbed inth.e patents.cited ~hover and there-rore need not ~ rurther detailed here.
; In accordance wlth the ln~entlon, as lncorporated ln such procedure, the rlber array 10 ls exposed to steam at a locallty 30 lntermedlate the rlber dellvery devlce 14 and the locality 23 at which the backing ls applled ~o the ~ibers.

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As descrlbed above, the upper ends (as well as the lower ends) Or the rlbers at locality 30 are ~ree, l.e. they are not ad-hered to each other or to a backing, although they may be re-strained by belt 22 against vertlcal dlsplacement. Simllarly, the fibers themselves at locanty 30 are ~ree-standlng in the sense that they are not positlvely restralned agalnst lateral movement relative to each other and to the belt. Particularly important reatures and advantages Or the lnventlon reslde in the exposure Or the rlbers to steam prior to appllcation o~ an adherent backing to thelr ends, or in other words while the rlber ends whlch wlll be adhered to the backing are stlll ~ree, but arter the ribers have been assembled lnto a plle-orming array on the belt or other support surrace.
As lllustrated ln Figs. 1 and 2, a plurallty Or upwardly directed steam nozzles 32 are dlsposed beneath the upper run Or belt 12 at locallty 30, and are connected to a common header 34 to which steam is supplled rrom a suitable source (not shown) through a condult 36. The belt 12 ls rabricated Or a material su~rlciently porous (or psr~orate) to permit relatlvely rree pas~a~e Or steam therethrou~h, ~o that upwardly directed Jets Or steam rrOm the nozzles 32 pass .....
through the' ~el,t and through the array 10 Or ribers. The upper belt 22 ls pre~erably also porous to permit the steam to escape upwardly rrom the array. Desirably, the belts are pre-heated (l.e. berore they come lnto contact wlth the steam) to a temperature hlgh enough to prevent condensation Or moistllre on the belts and/or ~ibers; to this end, heating means ror the belts, represented ln Flg. 2 as generally conventional radiant heatln~ elements 38, may be dlsposed adJacent the belts ahea~
Or locallty 30.

- 8 _ Thus, ln the per~ormance o~ the present procedure in the embodlment represented in Figs. 1 and 2, the assembled lbers 11 ln the array 10 advancing on belt 12 through local-lty 30 are sub~ected to ~ets of steam directed upwardly, i.e.
transversely Or the plane Or the belt and genera~ parallel to the axial orientation Or the ~ibers, rrom the nozzles 32.
The steam, passing through and permeating the interstices Or the riber array, acts on the ~lbers to cause them to swell, spread, or bloom, much as the free extremitles Or rlbers ad-hered to the backing o~ a complete pile article may be bloomed by a conventional steam treatment as heretorore known. That ~8 to say, the physical errects or the steam on the individual rlbers or groups Or ribers (e.g. ribers twisted into yarns) may be similar to the erfects heretorore produced on the rree extremi~es Or the pile fibers Or a cut-pile artlcle by steam treatment. In the present procedure, however, unlike such con~entlonal treatment, the spreading errect operates on the upper rree ends Or the ~ibers (i.e. the ends which will be adhered to the backlng) owing to the ract that the ribers are exposed to the steam berore tho backlng ls applled. Thus the latter rree ends or the rlbers are caused to bloom or spread by the steam, producing an errectlve densirication Or the rlber array ln the plane in whlch lt wlll be attached to the backlng as well as ln the parts o~ the ribers which will be remote rrom the backing. As a result, when the backing is applied, lt engages already-bloomed riber ends; these bloomed ends cover the backlng surrace substantially completely, vir-tually eliminating exposed port~ns Or backing surrace between ad~acent rlbers. Consequently, ln the produced pile article, _ g _ even very extensi~e wear Or the pile does not create a threadbare appearanc`e or bald spots.
The steam treatment Or the present invention, as . embodled,ror example, ~n the procedure lllustrated in ~lgs. 1 and 2, also contributes to the control Or denslty, and attain-ment Or unirormlty, ln the ultimately produced plle. Slnce the rlbers 10 Or the arr~y 11 are rree-standlng ln the above-described sense at the locality 30, the bloomlng er~ect of the steam treatment tends to push the rlbers apart laterally, i.e.
to increase the,spacing between the axes Or adJacent ribers.
As already e2p1ained, the flbers as delivered,to the belt 12 2re lnltlally compressed withln the plle units 15 to a denslty , commonly greater than the deslred ultimate plle denslty, and arter release or.the pile unlts (by strlpping Or the sleeves 16), the unlts are caused to expand laterally and merge into each other e.g. by application Or approprlate ~orce. Thls expansion, into a continuous array Or substantially uniror~ly dlstributed flbers typically havih~ a lower denslty (number o~
~ibers per unit area) than the lnitial pile units, may ~ er-rected, wholly or partly, by the ~team treatment. That ls to say, the Qteam treatment may provide the 801e or principa~
applled force promoting expansion o~ the plle unit.s or may contrlbute to such expanslon ln cooperatlon with other applica-tlon Or rorce e.g. as described in the patents cited above.

As stated, one way in whlch the steam treatment pro-duces thls increase in spacing between rlbers ls by blooming or spreadln~ the indiYldual' ribers. In addition, in the em-~odiment Or ~i~s. 1 and 2, the rorce Or the upwardly directed Jets promotes such spreading or lateral displacement o~ the ~ibers. The extent of dlsplacement Or ~lbers resulting rrom the steam treatment ls dependent inter alia on the ~rictional rorces exerted by the belt or belts on the rlbers. Thus, i~
the belts are so-called high-rriction belts, ~eir engagement with the riber ends inhiblts lateral displacement of the ribers though lt does not prevent blooming Or the fiber ends;
on the other hand, lr the belts are low-frlctlon belts, the ribers mo~e apart r~ktively easily under the inrluence o~ the steam.
The errect Or the steam treatment in laterally dis-placlng the rlbers contributes very slgnlrlcantly to deslred unlrormity Or riber distrlbutlon ln the pile. As will be understood, in the expansion of the pile units on the belt surrace, whether resulting simply ~rom release Or the pile units or promoted by applied ~orces, gaps or interstlces Or unequal slze may remain between ad~acent ribers in local areas Or the array 10. When the rlbers are exposed to steam at the locality ~0, lateral dlspla¢emcnt Or rlbers occurs prereren-tlally into these gaps, where there is le8s resistance to such displacement, so that the unirormity ~ distribution o~
the ribers throughout the array ls enhanced.
lt will be appreciated that the lateral displacement Or the rlbers by the steam is agaln attrlbutable to the ract that the rlbers are sub~ected to the steam treatment before they are rlxed to any backing. I~ the steam treatment were applied only to ~lbers already adhered to a backing, as in prlor practlce, the ~lbers would be held by the backlng against lateral dlsplacement although their ~ree extremities could .. ; . ............................ . ~
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bloom and spread.
Use Or the upper belt 22 is particularly deslrable when the ribers are sub~ected, as ln Figs. l and 2, to ~ets o~
8t~am passlng through the ~lber array with substantial force.
~elt 22 restrains the fibers agalnst the vertlcal displacement that might otherwise occur owlng to the rorce Or the Jets.
In addltion to the preheatlng o~ the belts ~or pre-ventlon Or condensation as descrlbed above, the array Or ribers together with the supporting and restrainin~ belts or s~rraces may be subJected to drylng a~ter exposure to steam, 1~ deslred, ror example by advancing the fiber array on the belt 12 through a drying chamber (not shown in Flgs. l and 2).
Drying removes any excess molsture that may be present ln the rlbers as a result Or the steam treatment without detracting ~rom the bloomlng or spreadln~ errect produced by the steam.
Also lr desired, the ribers Or the array lO may be subJec~ed ~o a succession Or steam treatments with or wlthout inter~edl-ate or rollowlng drylng stages, prior to application o~ the backlng, ln order to achleve progresslve or stepwlse bloomin~
an~ ~preadln~ Or the rlbers.
~ t wlll be appreclated that ~e speclric physieal errects Or the steam on the rlbers are dependent on the nature Or the ~lbers and the nature Or the applled steam. Thus particular klnds Or rlbers may exhiblt a greater or lesser degree Or crimplng and/or some reductlon ln axial length under expo~ure to steam. The type Or steam employed, i.e. wet steam, dry steam, superheated steam, etc., may be selected the operator rOr partlcular appllcatlons, as will be ap-p~rent to those skilled ln the art rrom the e~ects Or :' ' " ' . :

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dirrerent types Or steam treatment on dirrerent types Or rlbers already adhered to backings.
Although inFlgs. 1 and 2 the backlng 24 is repre-sented ln the rorm Or a web ha~ln~ adheslve applied to its surrace for securing the rlbers to the web,cther types Or backlngs may be employed. For example, a backing may be ~ormed dlrectly on the upper rree ends Or the array at locality 23 by spraylng or applylng onto the riber rree ends a fluld materlal which solldiries to constitute an adherent backing.
The errect Or the steam treatment ls rurther illus-trated ln Flg. 3 which shows the array Or ribers 10 between concurrently advancing porous belts 12 and 22 durlng exposure to a Jet Or steam dlrected upwardly through the belts from one o~ the nozzles 32. The bloomlng errect Or the steam on the rlbers is schematlcally represented as an enlargement particu-larly at the upper and lower rree ends Or the rlbers lla on the rlght-hand or downstream slde Or the array as compared wlth the ~lbers llb on the lert-hand side Or the array ~ust enter-lng the steam zone. The increase in axlal spacing beSween adJacent rlbers i3 also evldent by comparlson Or the treated rlbers llb wlth the untreated rlbers lla.
Whlle the procedure Or the lnvention has been de-scrlbed as per~ormed to treat an array Or ribers carr~ed on a movlng endless belt, the ribers sub~ected to the treatment may be supported in other ways. For example, the rlber array 10 (havin~ the same characterlstics as described above) may be establlshed on or dell~ered to a statlonary perrorate plate through whlch steam ls passed, and arter the steam treatment, a backing may be applled to the rree ends Or the rlbers - .

~ 3 ; while they are still supported on the perforate plate. Ir ~ets o~ steam are used, dlrected perpendicularly to the.plane ,~ .
o~ the per~orate plate, a per~orate top plate (correspondlng positionally to belt 22) is preferably also employed to re-strain the ~lbers against dispiacement ln an axlal directlon.
~he arrangement Or an array o~ ribers on a statlonary per~or-ate plate (wlth a retainlng perrorate top plate) may be under-stood ~rom Fig. 3, i~ elements 12 and 22 are considered as ~tatlonary plates or support sur~aces rather than movlng belts.
Flg. 4 lllustrates dlagrammatlcally the lncorporation Or the present procedure ln a -~ystem (ror producing nonwoven pile carpet~ or.other nonwoven plle articles) somewhat more complex than that shown in Flgs. 1 and 2. Means represented ror simpliclty as an endless belt 40 conveys the array Or ~lbers lO rrom the rlber dellvery devlce 14 twhlch may be the same as that Or Flg. 2) through denslty control mechan~sm 42 where, ror example, the lnterriber spaclng may be increased to reduce the den~ity Or the plle array, ror example as dls-closed ln the patent~ cited above. Belt 40 then ~uccessively conveys the ribers through a heating zone 44 where th~ belt and ~lbers are preheated, a steam zone 46 where the rlbers are bloomed by exposure to steam, and an optional drylng zone 48 where excess molsture remalning rrom the steam treatment may be removed as by application Or heat ln a dry atmosphere. The steam-trea.ted ~ibers havlng bloomed ~ree ends are rinally carried by the belt 40 into contact with backing web 24 whlch has an adhe31ve-bearlng sur~ace ror an-choring the ~lbers to the web to produce a complete plle artlcle.

- 14 _ I~ desired, between the fiber dellvery device 14 and the locality o~ application o~ backin~ web 24, there may be pro-~ided a suc cession of densiSy control mechanisms 42, e.g.
ror errectlng stepwise ~ncrease in separation o~ ribers o~ the array 10, and each Or these density control mechanisms 42 may be indlvidually ~ollowed by a steam zone 46 to correct any nonunirormlty in riber distribùtion that may have been intro-duced into the array by the immediately preceding density cantrol mechanism.
Illustratlve examples Or density control mechanisms, descrlbed in detail ln one or more o~ the patents cited above, include ~iber-c~rrying endless belts rabricated Or an elastic material and sub~ected to progressive lateral or longitudinal expansion whlle supporting the ~lbers, as well as successlons o~ belts drlven at respectively dir-rerentvelocltles.
Re~erring to Fl~. 5, there are shown a succession Or three belts 50, 51 and 52 havlng upper runs dlsposed in a com-mon plane ror se~uentlally supportin~ an array Or ribers 10 advanclng in the directlon lndicated by arrow 53. Belts 50, 51 and 52 may be respectively drlven at successlvely greater velocitles, i.e. belt 50 being the slowest Or the three belts ant belt 52 belng the rastest. In thls way, as the rlbers Or array 10 advance succeæslvely over the three belts in the dlrectlon Or arrow 53, they become spaced progressively ~urther apart, decreaslng the overall density of the riber array.
With each Or the belts 50, 51 and 52, there is associated a corresponding upper belt 50a, 51a or 52a having lts lower run drlven in the same dlrectlon and at the same velocity as the .

assoclated sub~acent belt, to restraln the rlbers Or the array agalnst vertlcal dlsplacement.
It wlll be understood that ~e described arrangement Or belts ln Fl~. 5 constitu2s one rorm Or density control mechanism ror progressively reduclng the density Or a riber array ln a controlled manner determined by the relative velo-cltles Or the belts. Intermedlate successlve lower belts, stationary support members 54 are mounted to support the ad-vanclng ribers as they are transrerred from one belt to the next. Corresponding stationary restraining members 56 are mounted above the members 54, between successive upper belts.
In accordance wlth the inventlon, each Or the support members 54 may have one or more passages 58 rormed in it and openlng upwardly. Steam is supplied through passages 58 so as to pass upwardly thererrom through the advancing riber array 10. The upper members 56 may, as shown, be hollow and per-rorate to conduct the steam away rrom the array Or ribers.
In thls embodiment Or the inventlon, the successive applications Or steam serve to bloom the riber rree ends ln the manner already de~cribed prior to application Or a backing thereto ~the backing being applied beyond the downstream end o~ belts 52 and 52a ln Flg. 5~ and also serve to promote lateral displacement Or the ribers so as to correct any non-unlrormity Or ~lber dlstrlbutlon resulting rrom the rlber array-expandlng stages. While dir~erential speed belts have been specirlcally described as constltutlng the denslty con-trol or array-expandlng mechanlsm Or Flg. 5, the belts 50, 51 and 52 (as also the belts 50a, 51a and 52a) may be elastic expandlng belts whlch stretch pro~resslvely and thus pro-gresslvely separate the rlbers supported on them. These belts, whether Or the dirrerentlal speed or expandlng type, are prererably hlgh-rriction belts; l.e. the ~ree ends o~ thé
ribers are-restrained by substantlal rrictlonal rorces against movement relative to the belt surfaces so that the di~ferential velocity or expanding e~fect Or the belts promotes riber separation. The surraces Or members 54 and 56 engaging the rlber ends may, by contrast, be low-rrlctlon surraces on which the rlber ends can move readlly to maximize the errect Or the steam in promoting riber dlsplacement ror rllling gaps in the array. It wlll Or course be appreciated that the ribers sup-ported on the surraces Or elements 54 are pushed ~orwardly (ln the direction Or arrow 53) by the advancing belt-trans-ported r$bers behlnd them.
Fig. 6 lllust~ates an alternatlYe arrangement rOr exposlng the ribers Or an array lO to steam. In Flg. 6, the ~lber array lO (establlshed, as ln the preceding embodlments arthe lnvention, by a suitable deliYery devlce on the upper ~urrace Or the upper run Or a drlYen endle8~ belt 20a) ls ad~anced through a substantlally ~ully enclo8ed chamber 60 havlng opposed lateral ports 61 and 62 to accommodate the belt and rlber array. Steam supplled to the chamber 60 through a conduit 64 rllls the chamber with a more or iess qulescent atmosphere Or steam which permeates the rlbers Or thearray 10 within the chamber and causes bloomln~ especlally at the rree ends Or the ribers. In this embodiment, the fibers are not subJected to the addltional displacln~ errect Or a directional ~low or Jet or steam, but the steam atmosphere produces the deslret bloomlng or spreadlng Or the indlvidual ribers. As - . . , , - . ~--.

be~ore, the belt and ~ibers may be preheated by suitable and e.g. conventional heating means (not shown) ahead o~ the locality Or exposure to steam and may ir desired be dried as by heating arter exposure to steam. Beyond the steam chamber 60, belt 20a carrles the array of bloomed ribers into contact wlth backing web 24, which has an adhe~ive sur~ace to which the ribers adhere, rorming a complete pile article.
A rurther arrangement ror applylng steam in accord-ance with the invention to an array Or ribers ls shown in Fig. 7. The array lO, supported as in Flg. 2 on lower porouC
belt 12 and restrained by upper porous belt 22, is advanced (be~ore appllcation Or a backing) past a locality where steam is dlrected upwardly through the belt 12 and thence through the rlber array 10 rrom a distributor 66 positioned immediately beneath the belt 12 and opening upwardly. A suction plate 68 to whlch suction is applied as through a condult 70 overlies belt 22 in opposed relatlon to the dlstributor 66. The suc-tlon plate 68 not only helps to draw steam upwardly through the array lO ~rom the dlstributor 66, but also tends to hold the upper ~ree end8 o~ the ribers against the belk 22. Thls latter errect is particularly desired when the array lO i8 constituted Or heterogeneous ribers havlng respectively dir-rerent axlal shrinka~e propertles under exposure to steam.
More specirlcally, in Fig. 7 the array lO is shown as constltuted Or ribers llc which exhiblt relatlvely little axial shrlnkage under exposure to steam in mlxture with ribers lld which exhiblt relatively greater axial shrinkage when expo,sed to 9team. As rlbers lld shorten durlng passage through the steam locality, their upper ~ree ends are held by the suctlon plate 68 agalnst the upper belt 22 so-that they shrlnk upwardly away rrom belt 12, but thelr upper ends remain in deslred coplanar relatlon wlth the upper ends Or ribers llc ~or subsequent appllcatlon Or a backlng to these upper ends.
In the ~oregoing ~escription, rererence has been made to use Or nozzles supplying upwardly directed ~ets Or steam to a rlber array 10. Alternatively, the steam may be supplied through downwardly directed ~ets rrOm above the array Or rlbers, indeed with good e~rect ln maxlmlzing the blooming Or the upper rree ends Or the ribers ror subsequent attachment to a backing. As shown in Fig. 8, which represents a modi~ication Or the Flg. 2 arrangement, the nozzles 32 dlrecting steam upwardly through pDrous belt 12 lnto the array 10 may be supplemented by ~urther downwardly oriented nozzles 72 disposed above belt 22, ~or directlng Jets Or steam downwardly lnto the array 10, i.e. so that the array is ex-posed to steam ~ets slmultaneously appliqd rrom both above and below.
A still rurth~r modirication Or the inv~ntion i9 illustrated in Fig. 9. The arrangement o~ Fig. 9 is slmilar ____~D.~hat-or-Fig. 1, i.e. including an array o~ ribers 10 ad-.. . ...... ...
~ancing on a lower belt 12 (and restrained against upwardv~rtlcal displacement by an upper belt 22) through a locality 30 where the array ls exposed to steam supplied throu6h noz-zles 32, and thence to a locality 23 where a backing web 24 havlng an adheslve surrace ls applled to the bloomed upper rree ends o~ the rlbers.
The arrangement o~ Fig. 9, however, rurther includes provlslon Or a ~econd backlng web 74, trained around a roller 75 and havlng adhesive applled to ~s sur~ace ~rom a source (not shown). This backing web 74 ls applied to the lower ~ree ends Or the ~ibers of array 10 which are thus sandwiched end-wise between the upper and lower adherent backing webs 24 and 74. In accordance with a ~urther reature o~ operatlon known in the art, the pile array 10 between the adherent backlngs 24 and 74 is subsequently sllced laterally as by a knl~e 76 to produce simultaneously two cut pile articles 78a and 78b. In ~his Fig. ,9 arrangement, the blooming errect o~ the steam on both the upper and lower ~ree ends Or the ribers at locallty 30~ i.e. prlor to adherence Or any rlber ends to a'backlng, produces,in both plle articles 78a and 78b substantially total coverage o~ the backing sur~ace by the adhered ~lber ends and resultant ~reedom from bare spots as the pile wears ln ser~ice.
A particularly e~ectlve way Or achievlng expanslon Or a plle ~lber array to a deslred and un~rorm denslty ls by mechanically agltating the array. One arrangement ~or er~ect-lng such agltatlon in con~unctlon w~th spplicatlon Or steam ~e.g. in a system Or the general type Or Flgs. 1 and 2) i8 illustrated in Fig. 10. As there shown, the ribers in the array 10, disposed between porous belts 12 and 22, are advanc-lng, ln the direction Or arrow 20 toward the locallty Or appll-cation o~ a backing. The lower belt 12 ls supported on a perrorate plate 80, whlch is in turn supported on sprlngs 82 on a ~ixed mount 84. Plate 80 is connected through llnkage 86 to means shown as a motor 88 ~or mechanically agltating the plate, and thu,s the belt 12 wlth the rlb,ers dlsposed thereon, in directions whlch may be transverse and/or parallel to the plane o~ the belt. As the motor ls operated to provlde the descrlbed agitatlon, steam ls supplied through nozzles 32 ~-2~- , .

beneath the plate 80, and passes upwardly through the plate perrorations and the porous belt 12 lnto the riber array. The agitatlon or ~ibratlon imparted to the ribers promotes thelr lateral separation even as the steam acts to bloom them, and can be controlled to pro~ide a desired extent Or separatlon, i.e. a desired pile density.
This comblnatlon Or steam and agltatlon or ~ibratlon may be employed advantageously, ~or example, in expanding the pile unlts 15 Or Flg. 1 (arter their slee~es 16 are removed) lnto a unlrorm continuous rlber array. Moreover, while belts ha~e been rererred to above, the a~itatlon may be applied to a plate on which the ribers are supported, prlor to applylng a backing to the ribers. Application Or agitatlon to the ribers berore and/or arter steam treatment also errectl~ely promotes expansion Or the array to a deslred density.
It ls to be understood that the inventlon ls not llmlted to the reatures and embodlments herelnabo~e speclrlc-ally set rorth but may be carrled out in other ways wlthout departure ~rom lts splrit.

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Claims (7)

THE EMBODIMENTS OF THE PRESENT INVENTION IN WHICH AN
EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED AS FOLLOWS:

1. A process for making a nonwoven pile article, com-prising the steps of (a) assembling an array of substantially axially aligned pile fibers having free ends disposed substantially in a common plane;
(b) exposing said array to heat while (c) supporting said fibers, by means of support struc-ture, in a condition in which the fibers are later-ally displaceable relative to each other in main-tained substantially axial alignment;
(d) mechanically agitating said support structure while said array is being exposed to heat, by vibrating the support structure, for laterally displacing the fibers of the array relative to each other in maintained substantially axial alignment; and .
(e) thereafter applying an adherent backing to said free ends to form a pile article.

2. A process according to claim 1, wherein the step of exposing said array to heat comprises exposing said array to steam while supporting said fibers on said surface in a free-standing condition; and further including the step of heating said surface and said array before exposing said array to steam for preventing condensation of moisture thereon from the steam.

3. A process according to claim 2, wherein the step of exposing said array to steam comprises passing a directional flow of steam through said array in a direction substantially parallel to the axes of said fibers while restraining said fibers against substantial axial displacement by maintaining a second surface in spaced parallel relation to said first surface with the fibers of said array extending between said first and second surfaces, at least one of said surfaces being pervious to steam, and said flow of steam being passed through said one pervious surface toward the other of said surfaces with sufficient force for effecting lateral dis-placement of the fibers relative to each other.

4. A process according to claim 3, wherein the assembling step comprises assembling a plurality of rows of pile units, each comprising a substantially radially symmetrical and initially laterally compressed bundle of substantially axi-ally aligned free-ended fibers, in side-by-side relation with the fibers of the pile units released from lateral compres-sion, each of said rows comprising a plurality of said pile units.

5. A process according to claim 3, wherein the as-sembling step and the applying step are performed at spaced localities, and including the step of conveying said array between said localities, and wherein the steam-passing, sup-porting and restraining steps are performed during the con-veying step.

6. A process according to claim 3, wherein the steam-passing step comprises directing jets of steam through said one pervious surface along paths substantially perpendicular thereto.

7. A process according to claim 3, wherein the as-sembling step comprises assembling an array of cut pile fibers which undergo effective dimensional modification upon exposure to steam.