US2608901A - Cylindrical absorptive fibrous body and the manufacture thereof - Google Patents

Description

Sept. 2, 1952 J. GOLDMAN CYLINDRICAL ABSORPTIVE FIBROUS BODIES AND THE MANUFACTURE THEREOF Filed Dec. 22, 1950 2 SHEETSSHEET l m w M M TL f N 0 W q N v 7 [MP AH E U m y y Sept. 2, 19 2 J. GOLDMAN 2,608,901

CYLINDRICAL ABSORPTIVE FIBROUS BODIES AND THE MANUFACTURE THEREOF 2 SHEETS-SHEET 2 Filed Dec. 22, 1950 Jaw/w 6 01 OMA/V Patented Sept. 2, 1952 UNITED STATES PATENT OFFICE QXLINDRICAL ABSORPTIVE EIBROUS',BQDY AND THE MANUFACTURE THEREOF 'Joseph Goldman, Highland Park, N. J assignor,

by mesne assignments, to Earnhardt Manufacw in C mpany. C tt c Q- a cemen tion of No t Car l na I ApplicationDecember 22, 1950,1Serial N 0.202.365

This invention relates to peripherally I confined gabsorptivefibrous substantially cylindrical bodies andithemanufacture thereof.

"It is an ob'ject of this invention to provide peripherally confined fibrous substantially cy- "lindrical bodies-Which exhibit a very high degree of absorbencyandwhich exhibit in very high degree capillary action longitudinally thereof whereby a very pronouncedwicking action is afiforded. "It isa further-object of this invention to provide a method-"whereby such bodies may be Q15 directing the absorbed liquid l ngit y within :the body-bycapillary action. The pronounced capillary action longitudinally-of the -new; product of-jthis invention is also of utility whenever a'pronounced wicking action is desired. "F orexample-thenew product of this invention serted in wounds in; performing surgical operai'tion "It is a .featureof flfiiS" inventionthat the fibers ,used"in-- the-fibrous body are disposed inunspun relation with the fibers oriented predominantly 'glongitudinally in" the body. The fibers are preferably-of;substantial length and preferably consistpre d'ominantly, i, e. numerically in major Proportion, f.10Ilg"fib$IS. Any fiber which is about';%"' in length or, longer is-regarded as a lo rrg fiber asgthis term is usedherein. The body .Ir ay'be; composed entirely of the long fibers al- ';though' a; certain amount ofshorter fibers may be yblendedtrierewith. It is -particularly with regard .,to,;t he. lon fibersjthat orientation predominantly.

'(i; e. inimajor proportion numerically) longitudirnally in'the bo'dy issignificant.

Q Fl .llft1llf83ltlll8$ of this invention relate to jth'e manner by which the unspun fibers are peripherally confined. j Preferably, the fibers are periplrerally confined' by wrapping a plurality of 4 composite strands about thefibers as in-itiallydisposed; in a-substantially cylindrical condition so --a s *to provide -opposit'ely inclined helices having --=-substantially spaced convolutions. -If--the strands 12 Claims. (Cl. 87.-6)

weremerely wound about the fibrous-bodyvima continuous condition'the strands would immediately unwindwhenever the fibrous bodyislseparated into lengths for intended uses of thebody.

According to the preferred practice of-this 1-invention, a composite strandzis made. up using. one

or'more strands composedof latent activatable adhesive material adapted to be activatedtorhave adhesiveness imparted thereto as by use of a solvent or-by application of heat. In conjunction with'thestrand or strands composed of latent activatable adhesivematerial there are onexor more strands composed of material that ":is

adapted to remain substantially unaffected when the latent activatable adhesive material .of the other strand or strands in the compositestrand is activated to impart. adhesiveness thereto. After the composite strand has been wrapped about the periphery of'the fibrous body, the

" is very well-adaptedfor use 'as a' drain to be in-. 3

latent activatable adhesive material in the composite strand is activatedthus bonding thesec- 0nd strandto the peripheral'fibers of the fibrous body. In this way, permanent peripheral confinement is aiforded so that the finished body' can' be severed'into' lengths Without unravelling enunwinding at the ends. It is significant .also that the confinement is provided by spaced convolutions provided by the strand material leaving the bulk of the peripheral surface of the. body in porous absorptive condition and substantially free of any binder. -While it is preferable :to use composite strands inthe manner aforesaid; it' -is possible to use strands composed entirely of latent activatable adhesive material and then merely subject the strands to sufiicient activation to cause them to adhere-to the peripheral fibers of the fibrous body without destroying their longitudinal continuity. Likewise, other expedients may be employed whereby the strands-carry the latentactivatable adhesive material so -that the strands may be bonded to the peripheral fibers of the-body.

The fibers contained in'the 'fibrous body may beany fiber which preferably is relatively inexpensive-and which may be available insubstantiallengths ofthe order mentioned-above. Ordinary cotton fibers ranging from about to' in length, or longer, are very well suited-for use according to-this invention although in combination with the long cotton fibers a minor proportion of shorter cotton"fibers suchas- 'cotton linters ranging from to inlen gthmay 'be used. Instead of cotton fibers rayonfibersmay be used when of the order of length.-.above-:in-

dicated. More generally any type of:fib er issuitable, although:itis-pre rabl im dental-e th s I ratus shown in Fig. '7 taken on the Fig. 7; and

or the like to use fibers which are relatively soft and pliable, being comparable to cotton or rayon in this regard and which, when associated in loose unspun relation, are highly absorptive. Cotton which has been cleaned in the conventional way to remove naturally occurring waxes is ordinarily preferred because of its absorptiveness and wetability and because of its relatively low cost. Cotton which has been treated with caustic solution as in the preparation of absorbent cotton is suitable. For dental roll uses the fibers preferably should be free of objectionable odor or taste.

Further features of this invention relate to the manufacture of the bodies above described. Thus when cotton fibers are employed the fibers may be subjected to a carding operation which has the effect of orienting the cotton fibers predominantly in the machine direction of the carded fiber web. The carded fiber web material with the fibers oriented longitudinally therein may thenbe condensed into sliver form and one or more of the slivers when disposed in the form of an approximately cylindrical body may be continuously moved longitudinally while simultane ously wrapping the peripherally applied confining strands thereabout by an operation such as braiding or winding. After the strand material has been applied, the confined fibers in the cylindrical body are subjected to an appropriate operation for activating the latent activatable adhesive comprised in the strand wrapping so as to bond the strand wrapping to the peripheral fibers of the cylindrical body. These operations can be carried on rapidly and continuously and the product can be produced at a very low cost.

Further objects, features and advantages of this invention will be apparent in connection with the following description of the practice of this invention as exemplified in connection with the accompanying drawings wherein:

Fig. 1 is a side elevation, largely schematic, showing one type of apparatus which may be employed in the practice of this invention;

Fig. 2 is an enlarged detail view partly in sectionof the portion of the apparatus of Fig. 1 at which the strands are applied to the fibrous body from the braider; f; Fig. 3 is a plan view on a further enlarged scale showing the application of the strands to the fibrous body at and adjacent the line 3-3 of Fig. 2;

Fig. 4 is a plan view of the fibrous body with the strand braiding applied thereto;

Fig. 5 is similar to Fig. 2 showing a modification;

Fig. 6 is a plan view taken on the line fi6 of Fig. 5;

' tion whereby the strands may be applied to the fibrous body by winding instead of by braiding;

Fig. 8 is a partially sectional view of the appaline 88 of Fig. 9 is a plan view of the apparatus shown in Figs. 7 and 8 taken onthe line 9-9 of Fig. 8.

Referring to Figs. 1 to 4,. the practice of this invention is illustrated in connection with the manufactureof the peripherall confined absorptive body by the application of composite strands to a preliminary shaped cylindrical body of untudinally in the cylindrical body, the strands being applied by a braiding operation.

In Fig. l, the cotton fiber is shown as being taken in the form of slivers Ilia and lllb from the cans I la and I lb. The cotton fibers in these slivers are fibers which have previously been subjected to a conventional carding operation which has the effect of orienting the fibers predominantly in the'machine direction of the web produced by the carding machine. In a carding operation the fibers are acted upon by the cylinder and doffer so that while many of the fibers occur so as to be hook-shaped in the web their direction is predominantly longitudinal in the web. This is the case particularly with regard to the longer fibers inasmuch as some of the shorter fibers may not be as effectively acted upon in their passage through the carding machine so as to orient them longitudinally in the web. By way of specific example, the cotton fibers may be mostly to A in length and the action of the carding machine is such that at least about 65% of the long fibers are oriented longitudinally in the Web. The web material produced by the carding machine is condensed into the slivers [0a and 10b that are stored in the cans Ha and [lb for feeding into the system of this invention and since the fibers have been oriented longitudinally in the web material taken from the carding machine they are similarly oriented in the slivers 10a and 16b.

In the specific example shown in Fig. 1, two slivers are employed, but if desired only a single sliver may be used or more than two slivers may be used. The number of slivers used will depend upon the desired diameter of the cylindrical body to be produced. For such uses as dental rolls or surgical drains, the diameter ranging from A" to /2" is usually desired, although bodies of smaller or larger diameter can be readily produced in the practice of this invention.

Supported by the table 42 there is shown a braiding machine 13. Braiding machines are extensively used for many purposes and their construction is well known. For this reason, the details with regard to the construction of the braiding machine 13 are not shown and the braiding machine is merely indicated schematically in Fig. 1. The particular system shown is adapted to wrap eight strands about the body of unspun fibrous material in braided relatlonr As shown in Fig. 1, the slivers lUa and Nb pass over the rollers [4a and [4b and over the rollers 15a and I51) so as to merge in the vertically disposed body I0 which is brought into an approximately cylindrical shape by the guide IS. The cylindrical body In passes up through the center of the braiding machine l3 and thence through the guide I! which is of an inverted funnel shape. The eight strands are continuously applied in braided relation to the cylindrical body 10 immediately above the guide H and below the eye 18 in the arm I?! while the body If! is being moved longitudinally upwardly. The strands are indicated in Fig. 3 by the reference characters 20, 2|, 22, 23, 24, 25, 2B and 21. As shown in Fig. 3, the strands 2B, 22, 24 and 26 are wrapped around the body [0 in a clockwise direction while the strands 2|, 23. 25 and 2'! are wrapped around the body ID in a counterclockwise direction. The strands are fed from the bobbins 28 of the braiding machine and while only four such bobbins are shown in Fig. 1, it is to be understood that the total number of bobbins corresponds to the number of strands employed, namely. eight in connection with the tHesebbBbins -Iu- 1n-':oi1e: dictiori while the other in bobbins are caused tatearoeha 'the 'loodyll in the opgiosite di- -posedi "'-Preferab1y this isacc'o'm'plisheti' bypassm -the hhdw O-W-iththe'hraidi g applied" thereto '--ii1to* tI'iefch'amber-32 ihto which a solvent such as acetone "is directed from the Simply line 33 mm*through atomizmg n'oz'zles 34. When the rfyihe thebraidihg comes, 1 contact with 'rhizerracethne; the ac'et' he-immediately es 't elliilose-"a'cetate' o the-strands m,

hmeed st'rahes 'cohipr-isihg the e sentiany on- I dhesiire streiigth impartiiig st rids y'adhesively ezgwsmm 156 is PQSSBdRthrO'I-IghiihSE sol vent imecoveryschamber andthence1through the heated;drying-c;,eham- :onitheireel 3"lyfor saleiinpcontinuousform'; EA-Iter- 5 mativel-y; the product maynbeseveredzintoz suitable :length's and'soldiinsuch-form: r

The 1 typical ,appearancetof: the finished-product is shown in i Fig. '4 with .thetbraiding appliedflto theperipher'al; surface of: the body" l'o'ifor confiner tially cylindricalxform; The'zappearance: is-yrthe :same bothwafter :and :before the, strands'izare :bonded. :to the-periphery of the :body L0 Except for-.t=he-:app1ied1 strandsftheiperipheralasurataeeeof ethe body i flr is -in porous-i absorptive :conditiomso that fluids may -:be-: readily r; absorbed rr-irom -z-the :periphery*into'i'thefinterior. Duetozthefactfthat rthezbody- 10 consists preidom-inantly ofllong fibers -wh-ichfare rpredominantly: orientedaiongitudinally,

theistructure of the :body 1 0i is such "thatditsexthibits an extremelylarge? amount; of capillarityiin longitudinal directions". This isvthei: case vboth aasrregardstfluids:absorbed into the body- 10 from the'periphery" thereof *and :as regards anyi fluid :which-"may-E enter :thewbody I 0: from either- =.;end.

Thus; the newiproductis; suitable both "for zefi'ect- Zing; a very"great amountcof absorption ZOfTflllid from" the periphery" and is: likewise adapted: for "21158"Wh6116Ve1'=,3j'WiCking'aCtiOn is Jdesired ,-::1as,:for

ffmFigs; 5 and 6 is illustra-ted the-employment -0f a; modification. The?showingainrFigsai5:and- 6 is hidentical withi that of 2-except'ithatithe guide ifis provided with a 'centrallwlocatedrrod 3 3 8 which is: held in: positionrbyfithe webs 3 9. The

, w and :extends a-'substantiakdistance b'elow-ztihe guide TF1.

idevice is'iof' some advantage inmaintaining? the body 10' inalignment as lit :passes' upwardly :through: the reg-iomwherefthestrands arebr'aided thereon Thus; the rod 38f-servesxto'prevent :any "inequalities in tensionimposed" -by rthe ,zapplied strands from pulling the body I!) Out of-aproper alignmentiidu-ring ritsf passage athrough'tithejbraidifurther: function in that: {it occupiestherinterior oft-the body lflrat the-time'thatwthe braiding is aappliedthereto. "JIfhe application o-f+the=bra-iding reflects: some compaction -ofhthe\unspun fibers .and

such:compaction usinggthe modifieationshow-m in s; 5 and 6, ishlimitedsto theszone disposed vv.abouththe rook 3 8. 'Wh'en theuboldy-l [this moved L beyond thegupper end; of hthesrbd 318,, -.the'n ,the lf bers, withirii-the' bodyqarelifreeltoh fill lthe hollow lfl passes beyor'idfitherddjB'B; .In tthisfl-wayj the strands; can' be zmplieekilunder siibstanti'aL tension a q-thehompactmg t h'dncyj resulting 'frbin,the *tierisior {is relieved when thelb'ody pas's es' the upper e'n'd ofithe'rod 38 sothat"thej'fibers beobine free m assun'ie' a very'loo'sely jcompacted" :ahd absorptive conqit-ion. The employment :of fthe --ar'r ai1'geiriiit shoWri-in'Figsh f desirable-when?th roductp'rbduced'isaii enided w be composed of very loosely corhp'act'edfibers :ih h highly: absorptive condition;

An:altern'ative method'of prodiicihgthpifo'duct -wi11= now: e desc'ribe'd 'iri doiinectieri with ieigs. 117,: of aa 9 In generm, the pr huct i prddiiced rte 6, apiflied 0- he I aS dis'tifigiJi'sheWfroih a Fi si-ihra The rod '38-during.:operation;of-:the

'each of these strands being indicated by the reference character 63. Four of these strands Y are fed from bobbins 40, 41, 42 and 43 which are carried by the annular plate 44 rotatably mounted about the bearing member (if which is upstanding from the base 62. The annular plate 44 is rotatable in one direction from the driven pulley 45 through the bevel gears 46. The bobbins 41, 48,49 and 50 are carried by the inner plate 5| which is rotatable in the opposite direction about the bearing member El from the same driven pulley45 through the bevel gearing 52. The strands from the bobbins are wound about the fibrous body I which'is continuously moved up through the winding machine in the region between the guide 53 and the eye 54 in the arm 55. The strands from the bobbins 47, 48, 49 and are wound about the body H3 in one direction and immediately thereafter the strands from the bobbins 40, 4|, 42 and 43 are wound about the body I!) in the opposite direction. The body in may be formed from slivers taken from cans in the manner shown in Fig. l and described hereinabove and may be moved upwardly through the machine by passage over the periphery of the wheel 56 that is rotatably mounted at the upper end of the frame member 64. The wheel 56 may be rotated simultaneously with the rotation of the plates 44 and 5| by means of the chain drive 51 between the sprocket gears 58 and 59.

have been wound thereon will have the same general appearance, for example, as that shown I imFig. 4 except that all of the strands wound in one direction will overlie the strands wound in the opposite direction at their points of inter- 7 section.

After the strands have been applied to the pe-- riphery of the body ill in the manner described in connection with Figs. 7, 8 and 9, the body If! withthe strands wound thereon may then be subjected to appropriate treatment for activating the latent activatable adhesive material in the strands as described hereinabove and illustrated in connection with Fig. 1.

In Figs. 7, 8 and 9, the guide 53 is in the form of a simple aperture through which the body passes, but, if desired, the guide 53 may be of the type shown in Figs. 5 and 6.

While a composite strand has been illustrated hereinabove as containing one strand of cellulose acetate and a second strand of rayon, it is apparent that other materials can be used in the composite strand in accordance with the practice of this invention. As the strand which remains substantially unaffected when the material of the other strand is activated to impart adhesiveness thereto, any suitable material may be employed and the one which is used will depend principally on the matter of cost. While rayon is suitable for the purpose, an ordinary cotton thread can be used. Any other material such as silk or wool may also be used. For use as the strand composed of latent activatable adhesive, other materials than cellulose acetate may be employed. The material may be such that adhesiveness can be imparted thereto either bythe action of a solvent thereon or by the such as ketones, alcohols, ethers, esters and aromatic hydrocarbons, but is also thermoplastic and can have adhesiveness imparted thereto by application of heat. Moreover, it is possible to use heat in conjunction with the use of a solvent. A material such as a polyethylene may likewise be used and this particular material can readily be activated to impart adhesiveness thereto by use of an aromatic hydrocarbon or by application of heat. Polyethylene has a relatively low melting point around 250 F. and is thus readily susceptible to activation by application of heat. The latent activatable adhesive of the strands a: may also be composed of a material such as nylon which is not only thermoplastic, but also can be activated by alcohol. Other examples of suitable materials are polyvinyl alcohol fibers, chlorinated polyvinyl chloride, polystyrene and ethyl cellulose. Ordinarily, the best results are obtained when the latent activatable adhesive is activated by use of a solvent and the solvent preferably is applied by atomization of the solvent into an atmosphere through which the wrapped body I0 is passed inasmuch as better control is afforded for keeping the latent activatable adhesive from migrating under the influence of the solvent away from the zone where the strand wrapping contacts the periphery of the body. However, the solvent may be applied in any other suitable way.

The composite strand may likewise be composed of more thantwo strands. Thus, there may be a plurality of strands of the latent activatable adhesive material or a plurality of the essentially non adhesive strength imparting strands. However, in any case the composite strand will comprise one or more strands which are capable of being activated to act as an adhesive binder and one or more other strands which, because of difference in solubility in a solvent or difference in thermoplasticity, or both, will not be substantially affected upon activation of the strand or strands of latent activatable adhesive material.

In the practice of this invention it is distinctly preferable to use composite strand material of the character aforesaid. However, it is possible to achieve some of the benefits of this invention, but to a lesser degree, by using a strand which consists entirely of latent activatable adhesive material. In such case, the strand used would be relatively somewhat heavier than the individual strands in a composite strand and, for example, a cellulose acetate strand of denier is suitable, although any of the other latent activatable adhesive materials may be used. When such a strand isapplied to the fibrous body, the external surface thereof can be activated either by use of heat or application of a solvent so as to cause its adhesion to the peripheral fibers of the fibrous body and if only the peripheral surface of the strand material is thus affected, the strand material will retain its continuity and provide the desired confinement of the fibers. The extent of activation of such a strand can be controlled by regulation of the time or the severity of action of the activating agent as by use of a relatively slow-acting solvent applid for a limited period of time. Another alternative would be to employ a coated strand, as for example, by applying to a strand such as above described in connection with strand 1/ a coating of some latent activatable adhesive material such as those above mentioned for use as the strand it. However, use of coated strandsis less desirable and involves the relato aeeomplish a still mordi complete longitudinal" 9 J15. tiv'ein expensmemoau. eperatinn; whic avoided by the use of composite strands charactersaboveidescribed s.

While; th s-in ention;nastpeen a itate connection;withaapplicationloteiahtstrandslte; 5 thQlfibIQllSbQd-X, ins-"apparent that the umhelz. of-strandsi employedrmayl be; yaried rso..as to; bee. r either:le ss.;.than.-or.mogze thaneight The-pum v benoistrandaemnloxed-wzilhdenendinnalgtupom the'.1diamete1:; of theglqedy; thehsnacip ehettaeen.

theweenvolutionsloithelstrands. andcthe speed-t atimhiclnthe fibrQllS; bQdy ispassed-throneh.the, maqhineghwhilepthei; strands. are: being-firemen: ther'eabbut; .Bmusingat number;oi -strandssueh; a,

be-greater tham: if: aalesserj'number pig; strandsc were-iaemployedyithusienabling; greater speedxatr. whichotlieeoperationsemam-be icarriedzontewhile, maintaining (Estrada-spacing: between; LhBgCBIl-a l VOllltiOllSi-J Ordinarily, for: *hondingqfree; .unsnun; 20,

desirablesadneatmthetaddedccostri1agslower-produca 0,,

tidn i-rat'eilandnlesseningmirthaperiphnali area -ot the bodyethatis lent-uncovered in porous-absorph-M tiVe;(lCOnditiOli. .:More;-', generally, the. maximum SIIaOi-DgibBtWQGI-l. @thehstrands'of the-strand'wrapL pings preierablyiisi less-than; the average length: V

of-the; fiberaemployed while sttlltleawingzsubstanel tia'l-r spacing between. the. strands; Moreover,v

while theistic-ands .haveebeenshown asn wrappedtaabouti thefibro'usi hodyain the-.iformiofi'oppositehe inelineds helices, any other.- type; of strand wrap.- pingemaypba employed.- a a Assfan as. the finished? product is concerned; there; is. littleidiiferenca whether the '.'strands\ are applied bye braiding. as shown-.in-sconnection with- ;Li or arasapplied byewindina as. shown in conhectionewith Fi'gss-fl; 8 and 'Q-a 'fI-Iowever; it may be izientioned that the mech'anical: motions involved finathetoperation of:-'a braiding machine are: o'f 'suc h characteras -to impose a limi-t outliespeed -at: which the-braiding" operation can be carried out and while the product oi this inventioncan be prodticediveny rapidly in thisinanner; much hi-her A speedsof:- operation are possible whemth'e strands areapplied; by a simplewinding operationot thetypeaillustrated in connection-- withl' 'igsfl; '8; and 9:

-Whilereference-leas been--made hereinabove; to the einployment of a carding machine; for the; purposeeof orienting unspun fiber soas to be longitudinally disposed-fin afibrous body; other? expedients" iriay be; employedg for the purpose, depending partly-ongthe-natizreotthe fibers being handle 1 Thns there-are a number o f-- we1l known-devicesfor-= per-f0rming operations such; as combing, drawing and the lilr whichresu-lt in' longitudinal orientation ofthe fibers in; an elong -ed body;- 'Morover; while an; ordinary cardi" g operation is ordiharilysufficient; acarding peration may be:- supplemen-tecl b; drafting orientation-bi th' fibers. Inan-y-case; lion/"ever; theiinventi'on'coziternplates the orientation otthe- I unspumfibers so\ as? to occur.- predominantly; longitudinally-sin assubsta-ntially: cylindrical" elonv-l' gatedebodyz-andithe lapplicationaofiazstrandswrapa. v

m ambon'aedamelatiorttdthe per phe al su ac 75;; i

Such binder interferes with; the-absorptive ess .of the roll and, whe n a water-solublebindensn het lt; fib rh ef awardi ripheral surface isporous and absorptive and" 0.;

as to beessentially free of any surface applica tionr-such as a binder, While the product .oiithi invent onasmany'd fie entu s i s ofzespecial; 5 utility asa dental" roll and forsnch use in notable for its capillarity, for its, freedom from-anyrad verse'effectdueto contact with moistureQand fo its property- ,oi not sticking to thegnms}? In 4th past dental rolls have been produced byjtalgin a web of carded I cottonqor; the like, and" rolli A theweb; up inthe machine direction. of; the we untilv aroll oi desired diameter-is produced. S11 rolls are kept from unrolling; by a periphera overall application of a} binder suchas se r l as starch is used, the binder is dissolvedan ts effectiveness is destroyed as soon asv theroll comes in, CQntact with the moisture,-

uch .0111i;-hate. also been found tobeobjectionablein usedue to; their tendency to stick: to -the gurns-iespec llyf after-prolonged application; Moreover, in such," a roll; the-fibersare not. disposed redom' longitudinally in the-rollbutar spose pr 7 dominantly transversely, with'the flberidirectioii v following the.- spira1 oi therolledeup him er and with the, result. that the'rollhas tug c larity in the longitudinal direction. Itl-ishalso the case thatthe production ofdental rolls f manner inherently-involves much inore cornp e." ca ted, more time-consuming, and more expe sivemanufacturing operations as comparedwith, the practice of thisinvention.

ccordin i n eatioa. .-nej.w and: proved product -0f the characteldescribed ha ng A n e pron fies ndz ha racte i ticscan tap ng.

duced veryinexpensiely and atlavveryhigh pron. duction rate. Whil e e hod- Of h g nv n iq mear y ada ati n hemanuiaQ- u eof, sub tantiallt y r eal odiess ic asd fibers 1.1 lt a fprmiand eyhatetliestram momma. ppli d; thereto and canseditoe adhere 0.1 the: 116:4

eoacoi highly absorptive so that the spacing of the strand 7 convolutions may be of the order of that above described as appropriate when the fibers are preponderantly long fibers, but if more firm confinement is desired, the strands may be more closely spaced while retaining substantial spacing between the convolutions. However, by employment of preponderantly long fibers disposed preponderantly longitudinally in the cylindrical body and by use of the self-bonding strands whose spacing is less than the average length of the fibers a further constructional principle is utilized whereby the fibers in the body not only are peripherally confined but also are peripherally anchored so that in effect the core or body portion is contairied within a highly porouscylindrical shell which affords confining strength by virtue of the strands and which afiords longitudinal strength a by virtue of the multiplicity of the peripheral long fibers that are bonded to the strands between their ends. much superior product is afforded providing optimum all-around strength characteristics in combination with optimum porosity, absorptiveness and longitudinal wicking action;

I claim:

1. A method of producing a peripherally confined substantially cylindrical fibrous body which comprises arranging unspun fibers in the form of 0 an elongated substantially cylindrical body, said body comprising long unspun fibers oriented predominantly longitudinally in said body, moving said body, longitudinally and while said body is being so moved wrapping a plurality of composite strands about said cylindrical body substantially in the form of oppositely inclined helices with the convolutions of said helices in substantially spaced relation, each of said composite strands comprising a strand of latent activatable adhesive adapted to be activated to impart adhesiveness thereto by application of a solvent thereto and a second contiguous strand which is adapted to remain substantially unaffected upon application of said solvent thereto, and, after said strands have been wrapped about said cylindrical body as aforesaid, activating said latent activatable adhesive comprised in each of said strands by application of solvent thereto, thereby bonding the second strand comprised in each of said strands to peripheral fibers of said cylindrical body.

2. A method according to claim 1 wherein said solvent is applied to activate the latent activatable adhesive comprised in said strands by atomization of said solvent into the atmosphere in contact with the periphery of said body.

3. A method of making a substantially cylindrical absorptive fibrous body which comprises disposing long unspun fibers in an elongated body of approximately cylindrical periphery with said fibers oriented predominantly longitudinally in the body, moving said body longitudinally and while said body is being so moved wrapping a composite strand substantially helically about said cylindrical body with the convolutions of said strand in substantially spaced relation, said composite strand comprising a strand of latent adhesive material adapted to be activated to impart adhesiveness thereto and a second contiguous strand which is adapted to remain substantially unafi'ected when said strand of latent activatable adhesive material is activated to impart adhesiveness thereto, and after said composite strand has been wrapped about said cylindrical body as aforesaid activating said strand of latent activatable material, thereby bonding By this constructional principle, a

sen e-cane strand "to peripheral fibers of said":

cylindricalbody.

4. A method of producing a peripherally confined substantially cylindrical body composed pre dominantly of long unspun fibers which comprises orienting said long unspun fibers predominantly in one direction, disposing said fibers in a pe ripherally approximately cylindrical body with said long unspun fibers disposed predominantly longitudinally therein, wrapping a pluralityof strands comprising latent activatable adhesive material-adapted to be activated by application:

of a solvent thereto about said peripherally approximately cylindrical body substantially in the form of oppositely inclined helices'having sub-.

stantially spaced convolutions, and thereafter activating said latent activatable adhesive material to cause adhesion of said strands with peripheral fibers of said body by contacting the peripheryof said body with strands wrapped thereabout with an atmosphere containing finely-divided droplets of solvent for said adhesive dispersed therein. l

5. A method according to claim 4 wherein said wrapping of said body by said strands is performed continuously by abraiding operation while said body is being moved longitudinally.

6. A method according to claim iwherein saidoppositely inclined helices are applied: continue. ously by winding respectivfe strands sequentially t in opposite directions about said cylindrical bond while said body is being moved longitudinally.

l. A method of producing a peripherally connantly longitudinally in said body, wrapping a plurality of strands comprising latent activatable adhesive material about the periphery of said body while said central member is disposed within said body, separating the resultant wrapped body from the central member to permit the 11-;

bers of said bodyto fill the space afforded by separation of said member therefrom, andactivat-W ing said latent activatable adhesive material-to cause adhesion of said strands with peripheralfibers of said body.

8. A method of producing a peripherally con fined substantially cylindricalfibrous body which comprises arranging unspun fibers in the form of an elongated substantially cylindrical body whose diameter is at least of the order of about A inch, wrapping a plurality of preformedstrands comprising latent activatable adhesive material about, the peripheral surface of said cylindrical body in the form of substantially spaced convolutions while said latent activatable adhesivematerial is in non-tacky condition, and thereafter activating said latent activatable adhesive 'material to cause adhesion of said strands with peripheral;

fibers of said body. e r g 9. A method of producing a peripherally con-- fined substantially cylindrical fibrous body which comprises disposing unspun fibers in the form of an elongated substantially cylindrical body, wrappinga plurality of strands about the periph cry of said substantially cylindrical bodysub- V stantially in the form of inclined helices: having substantially spaced convolutions, said strands-- comprising com'positestrand construction wherein a strand of latent activatable adhesive material adapted to be activated'ttoiimpartEadhesivenesS' thereto is contiguous to a second strand which is adapted to remain substantially unaiiected when the strand of latent activatable adhesive material is activated to impart adhesiveness thereto, and after said strands have been wrapped about said cylindrical body as aforesaid activating said strand of latent activatable adhesive material thereby bonding said second strand to peripheral fibers of said cylindrical body.

10. A method according to claim 9 wherein said latent activatable adhesive is adapted to be activated by application of a solvent thereto and is activated by contacting the periphery of the body with said strands wrapped thereabout with an atmosphere containing finely divided droplets of solvent dispersed therein.

11. A method according to claim 8 wherein said latent activatable adhesive is activatable to im-' part adhesiveness thereto by application thereto of a solvent therefor and wherein said latent activatable adhesive is activated by contacting the periphery of said body with said strands wrapped thereabout with an atmosphere containing finely-divided droplets of solvent for said adhesive dispersed therein.

12. A dental roll consisting of a, substantially cylindrical absorptive body approximately to inch in diameter and of predetermined length suitable for use as a dental roll composed predominantly of fibers selected from the group consisting of cotton and rayon fibers which fibers are predominantly at least about inch in length and are disposed predominantly longitu- -dinally in said cylindrical body in unspun porous, absorptive and longitudinally wicking relation, the periphery of said body being confined by substantially spaced convolutions of oppositely inclined substantially helically disposed strands composed predominantly of fibers selected from the group consisting of cotton and rayon fibers with the maximum spacing of said strands longitudinally of said body of the order of to inch, and said strands being bonded to the peripheral fibers of said cylindrical body by a water-insoluble adhesive material which is adherent to said peripheral fibers of said body substantially solely where said strands overlie said peripheral fibers, the peripheral fibers of said cylndrical body between said spaced convolutions being in said porous and absorptive condition and essentially free of binder material.

JOSEPH GOLDMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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