US2219829A - Method of making elastic fabrics - Google Patents

Description

Oct. 29, 1940. M. c. TEAGUE ET AL METHOD OF MAKING ELASTIC FABRICS Filed Jan. 21, 1938 .7 Q T ll. a w Q a k 1 mm m .0 Nu \m Q Q m H. v ooooooo o b oo oooecmoooooooo X ooobrdooooooo000000090000|\ 3 m W 0 ll l \nU z W Nw Patented Oct. 29, 1940 UNITED STATES,

PATENT orrlca METHOD OF MAKING ELASTIC FABRICS New Jersey Application January 21, 1938, Serial No. 186,132

11 Claims.

This invention relates to a method of treating various textile fabrics to impart to them elastic properties, and also to an elastic pile fabric.

It has been proposed heretofore to form elastic fabrics from stretchable textile fabrics by securing a sheet of calendered rubber or a layer or coating of rubber to one face of a knitted fabric.

The. rubber imparts to the fabric the desired quick recovery from stretched condition and a 10} capacity to retract to substantially its original condition after being stretched.

It has also been proposed heretofore to stretch knitted goods in the direction of the courses and while thus stretched apply a rubber-containing III fluid to the fabrics to yieldingly retain them in the stretched condition to thereby increase the property of the fabrics to stretch in the direction of the wales so as to produce two-way stretch fabrics. In that process the tension on the 20 threads in the unstretched rubber treated fabric is increased over and above the tension on the threads in the unstret'ched knitted goods.

-In the first case above the extensibility of the fabric was not changed and in the last case above the effect of the treatment has been to make an elastic fabric, and to increase the property of the fabric to elongate in one direction with a loss of such property in a direction at right angles thereto, but such treatments have not served to increase on the whole the property of a fabric to elongate over that which the textile fabric originally possessed before the rubber treatment.

The present invention relates to a method of treating woven, knitted and other textile fabrics by condensing the fabric in the presence of a deposit or coating of rubber that may be uncoagulated or partially coagulated, and then yieldingly securing the parts of the fabric in this condensed condition by setting or vulcanizing said deposit or coating of rubber to thereby produce an elastic fabric.

One important feature of the present invention resides in the step of utilizing the rubber-containing fluid, firstas an adhesive to temporarily secure the fabric to be condensed to a condensing belt, and later as a permanent elastic'binder to yieldingly hold the parts of the fabric in the condensed condition. As a result of the present invention whereby the rubber-containing fluid serves first asa temporary adhesive and later as a permanent elastic binder, it is unnecessary to use a glue or similar adhesive to secure the fabric to the condensing belt and then subsequently re- 55 move such adhesive, as contemplated in the Mer- Wu C. Teague application No. 758,009 filed December-l8, 1934.

Another feature of the invention resides in the method of. condensing the fabric by confining or gripping it between 'a pair of stretched belts, to oneor both of which the fabric is adhered, so that the fabric is firmly held therebetween and is gradually condensed as these belts are permitted to contract.

A further feature resides in a method of condensing the fabric by confining or gripping it between adrum and a stretched elastic belt passing around the drum. The fabric is adhered to the belt and is condensed by the contraction of the belt as it passes around the drum.

Another feature resides in the steps of spraying or otherwise applying a rubber-containing fiuid such as rubber latex to the fabric, then applying a coagulant upon the latex before the fabric is condensed, and later causing the rubbercontaining fiuid to set by vulcanizing or partially vulcanizing it after the fabric has been condensed. The coagulant may be applied to the fabric in a weak solution if desired, but it is preferably applied to the latex.

Still another feature resides in a pile fabric produced by the present method. 7

The invention will be further understood from the following description when read in connec.-' tion with the accompanying drawing illustrating mechanism for carrying out the method, and an elastic pile fabric embodying the invention.

In the drawing:

Fig. 1 is a diagrammatic side elevation of one form of mechanism for condensing fabric 'between two stretched belts;

Fig. 2 is a diagrammatic side elevation of a different form of mechanism for condensing fabric between two stretched belts; 1

Fig. 3 is a diagrammatic side elevation of mechanism for applying the fabric to and condensing'lt on the inner face of an elastic belt;

Fig. 4 is a longitudinal sectional view through a piece of pile fabric before it is condensed; and

Fig. 5 is a view similar to Fig. 4 showing the fabric as condensed and secured in this condition by a rubber backing.

The method of the present invention may be employed in treating knitted, woven, lace or other fabrics to render them elastic, and-these fabrics may be condensed either longitudinally or transversely or both longitudinally and transversely, as dsired. The extent to which it is practicable to condense a piece of fabric-depends largely upon how open a construction the fabric is given when 65 originally produced. It is obvious that-a loosely formed fabric may be condensed to a much greater degree than a firm closely produced fabric.

In the construction disclosed in Fig. 1 of the drawing the fabric F to be made elastic is supplied by a roll I0, and is adhered to a stretched condensing belt II, to be described, with a rubbercontaining fluid which may take the form of a solvent rubber cement which does not soften when under heat of vulcanization to such an extent as to release the condensed condition of the fabric, or an aqueous dispersion of rubber such as rubber latex with or without compounding and/or vulcanizing ingredients andin either a vulcanized or unvulcanized condition to a workable degree. Some of the solvent rubber cements of the class referred to above are those made from crude rubber without mastication and from reclaim rubber which contains combined sulphur.

It is desirable to use a desolvating agent during the solvating step to provide a maximum rubber content and minimum solvent content. Rubber containing fluid as used herein shall include any consistency or viscosity of the rubber containing materials which may be sprayed, spread or applied by a pick-up roll or the like. The rubber fluid may be applied to the fabric or to the condensing belt, or to both but it is deemed preferable to employ rubber latex to impart the desired elastic properties to the fabric, and to apply it to the fabric by means of a spray. In the construction shown in Fig. 1, the latex is applied to the upper face of the fabric by the nozzles L and L.

The present inventionas above stated contemplates using the adhesive action of the rubber coating to temporarily secure the fabric to the condensing belt. It is therefore important that the coating upon the fabric be in a taclw condition when the fabric reaches the condensing belt.

This tacky condition may be secured by heating or drying the latex upon the fabric, or by coagulating the latex either by heating or spraying a coagulant thereupon by means of the nozzle 0, or a heat sensitive latex may be used. A second coating of latex may be sprayed on the fabric at L' to increase the tacky condition. The heating or partial coagulation of the latex may serve also t'o make it less fluid so as to prevent too deep penetration into the fabric and to prevent it from flowing together to close the apertures of the fabric. The spraying nozzles 1 L' and C are preferably inclined to the fabric as shown so that the spray will not be forced through the fabric but will be deposited upon the upper face thereof.

The fabric F is condensed in the construction from slipping therebtween. The large drum [2 is positively driven and the smalldrum I3 is positively driven at a slower surface speed. The effect of this is to tension the lower run of the belt I I and to permit the upper run of this belt to contract The outer=belt I5 like the inner belt II passes around the large drum I2 and' together serve to tightly grip the fabric F between the two belts. The outer beltis shown as passing around the spaced drums I6 and I1 and the upper drum I6 has cooperating therewith the pinch roll I8, and

the lower drum I I may be a free-running drum. The drum I6 is operated at a slower surface speed than the large drum I2 so that the lower run of this belt will be stretched and the upper run relaxed similar to the belt I I.

In the construction shown in Fig. 1 it is assumed that the rubber-containing fluid is deposited upon the upper face of the fabric F which engages the inner belt II so that the fabric will adhere to "this belt instead of to the outer belt I5. A pinclrroll I8 may be employed to press the belts II and I5 firmly together against the drum l2 tocause the fabric F to be firmly secured to the belt II by its adhesive rubber coating. This pinch roll'serves also to prevent slippage between the drum and belts at this point.

It-will be apparent from the foregoing that when the treated fabric F is introduced between the stretched lower runs of the belts II and I5 it will be strongly gripped between these belts as they pass around the drum I2, and that'as these belts' and the fabric approach the upper quadrant of the drum II, in the construction shown, the belts will be permitted to contract gradually, with the resultthat the fabric therebetween will be condensed gradually. The rubber-containing fluid will cause the fabric to adhere more or less firmly to the belt II, and the contraction of this belt will therefore serve first to condense the fabric and then to hold it in the condensed condition. The treated and condensed fabric may be conducted by the belt II past the drying or heating mechanism I9 which will cause the rubber to set or become sufficiently vulcfanized to yieldingly hold the fabric condensed. The fabric may then be stripped off of the belt I I and wound upon the roll 20, whereupon the rubber may be further vulcanized or otherwise treated. For example, two such fabrics may be plied together but in order to unite the two fabrics latex or some other adhesiv e may be introduced between them.

In practicing the method of Fig. 1, the tacky condition of the rubber coating and the confining pressure between the belts II and I5 are both employed to condense the fabric. This is desirable in condensing heavy fabrics, but in condensing light fabrics the tacky condition alone may be sufficient to retain the fabric in firm engagement with the belt II as it contracts and the belt I5 may be eliminated. Where the belt I5 is also used it may be desirable in some cases to treat the belt so as to give it a more or less tacky surface to which the fabric will temporarily adhere. In condensing some light textile fabrics it is not essential that the latex be rendered tacky before the fabric is condensed between the belts II and I5.

In the construction shown in Fig. 2 the fabric F is supplied by the ro1l.2| and as it is unwound from 'this roll the rubber-containing fluid is sprayed against its lower face at 22, or a rubbercontaining fluid and then a coagulant may be deposited upon the fabric by the different nozzles 22. The rubber containing fluid and coagulant mayalso be applied to the upper face of the fabric. The fabric may then be partially dried by'the heater 23 and/or fan 24; The fabric is then introduced between stretched portions of the cooperating elastic belts 25 and 26.

- The lower belt 25 passes around the spaced drums 21 and 28 and the upper belt 26 around the spaced drums 29 and ill, and each of these drums is provided with a cooperating pinch roll 3|. It is important that the fabric to be condensed be firmly gripped between the adjacent stretched runs of the belt 25 and 26, and in the construction shown heavy non-elastic belts 32 and 33 are provided to back or support the fabric-engaging portions of the elastic belts. The lower non-elastic belt 32 passes around the drum 2'! and a drum 34, and the upper non-elastic belt 33 passes around the drum 29 and a drum 35. The adjacent runs of the belts 32 and 33 are held close together by the series of supporting rollers 36, arranged in rows above and below the adjacent runs of the belts. Each row is preferably mounted in a separate frame for adjustment toward each other, and these frames preferably diverge slightly in the direction in which the fabric travels, as will be apparent from the arrangement of the rollers shown in Fig. 2.

The drums 21, 29, 34 and 35 are all operated at the same surface speed and the drums 28 and 30 are operated at aslower surface speed with the result that the runs of the elastic belts 25 and 26 will be stretched when they first engage the fabric F and will tightly grip the fabric therebetween, but as they pass between-the slightly diverging rollers 36, the pressure of the non-elastic belts against the elastic belts decreases. This will permit the elastic belts to gradually contract to condense the fabric which may be more or less firmly secured to the belt 25 by the rubber-containing material. After the fabric is condensed it may be carried by the belt 25 below the heater 31, and then stripped ofl this belt and wound upon the roll 38, as above described in connection with Fig. 1.-

In Fig. 3 a third construction for carrying out the present method is shown. -In this view the fabric F to be treated is supplied by the roll 39 and as it is advanced towards the drum 40 it may be sprayed with latex at L and if desired,

with a coagulant atC so as to cause the lower face of the fabric to bev in a tacky condition as itreaches the stretched belt 4| passing around the drum 40. The latex may also be reduced to the tacky condition by drying as with a fan or heating as described in Fig. 2. If desired the latex or other rubber-containing fluid may be applied to either the surface of the fabric or the surface of the belt to be run adjacent each other and where the coeflicient of friction between the belt 4| and the fabric F is sufficient to condense the fabric, the rubber-containing fluid may be applied toeither the surface of the drum or the surface of the fabric runningadjacent thereto. The belt 4| passes around a drum 42 where it is engaged by the pinch roll 43, and the drum 42 is driven at slower surface speed than the drum 40 so as to stretch the lower run of the belt 4| and permit its upper run to contract gradually as it passes around the upper quadrant of the drum 40. The belt 4| may also pass around the free running rollers 44, and a pinch roll. 43' is preferably provided to force the belt 4| firmly against the fabric near the point where the belt and fabric meet the drum. This causes the tacky fabric to be firmly secured tothe stretched belt 4| and to be condensed as the belt contracts.

.The constructions shown in Fig. 1 andFig. 3 utilize the tension of an elastic belt to press the fabric against the drum and this serves to hold the fabric in a smooth fiat condition while it is being condensed. The rubber-containing liquid upon the fabric may if desired be partly dried or partly coagulated as it passes around the drum l2 or 40 respectively by heating these drums. Care should be taken however, not to set the rubber by vulcanization before the fabric is condensed. The condensed fabric upon leaving the drum 40 may be carried past the dryer or heater 45 to dry and partially or completely vulcanize the rubber and then the fabric may be stripped off the belt 4| and wound upon the roll 46, after which the rubber coating may be further vulcanized or otherwise treated as desired.

The elastic belts ll, I5, 25, 26 and 4| may be formed of a poro or non-porous rubber sheet or of a length of webbing, and the webbing if woven of elasticwarps and non-elastic wefts can be stretched longitudinally without contracting appreciably transversely. In condensing a woven fabric it is frequently important to use a belt the I width of which does notvary appreciably as the belt is stretched longitudinally and then permitted to contract, for a woven fabric tends to pull away from a belt that expands transversely as it contracts lengthwise. It may be desirable in some cases to condense less than the entire area of the fabric to impart a design or pattern eifects to the fabric. This may be done by using a perforated belt or by applying the rubber-containing fluid to the fabric F at selected areas, or if desired by applying an adhesion preventing material to parts of the elastic belt to prevent the tacky fabric from adhering to the belt at these points.

In some cases it may be desirable to produce a two-way stretch fabric. To accomplish this a knitted fabric may be stretched longitudinally to contract it transversely and may then be condensed longitudinally as above described. The fabric which is now condensed both transversely and longitudinally may be yieldingly retained in this condition and made elastic by providing the same with a coating of rubber vulcanized thereupon. For' example, a two-way stretch knitted fabric may readily be formed upon the mechanism of Fig. 1 by stretching the fabric F, in this case a knitted fabric, longitudinally so as to con tract it transversely before it is gripped between the'stretched belts I l and I5. Then as this fabric passes around the drum l2 it will be condensed longitudinally as above desscribed so that by the time the fabric is released by the upper run of the belt l5 it will be contracted in the crosswise direction and condensed in the longitudinal direction, so that if thelatex applied to the fabric at L and L is now vulcanized by the application of heat at It, a two-way stretch fabric will be produced. Such two-way stretch fabric may be similarly produced upon the construction shown in Fig.2 or Fig. 3.

A two-waystretch may also be produced from a textile fabric having substantially no stretch in either direction. This may be done by stretching the condensing belt both longitudinally and transversely before the fabric is adhered thereto, and then releasing the tension in both directions and condensing the fabric in both directions.

The elastic fabric made in accordance with the extent and it is given acloser texture in appearance. The term condensed as applied to the textile fabrics shall mean that the fabrics are contracted in either their longitudinal, or transverse direction, or both of such directions and to va greater extent than at the time the textile fabrics are adhered to the stretched condensing surface, and that the threads in such fabrics-are relaxed in oneor more of such directions to a greater extent than the threads in the normal unstretched textile fabrics and the term "relaxed" as applied to the present invention shall be'so construed. As compared to the normal finished condition of the textile fabrics used, the textile fabric lamina or laminae so condensed has an additional stretch imparted to it in either the longitudinal or transverse direction, or both of such directions without diminishing the original amount of stretch in any direction.

In- Fig; 4 is shown in longitudinal section a piece of pile fabric which may constitute the fabric F before it has been condensed, and Fig. is a similar view of such fabric after it has been condensed upon the apparatus ,shown in Fig. l, 2 or 3 or by other means. It will benotedthat the pile tufts T are closer together in Fig. 5 than in Fig. 4 and that the ground fabric is held in a condensed condition in Fig. 5 by the rubber backing B so that it may stretch under tension. The rubber backing Bis bondedto the condensed ground fabric and to the base of the tufts T, and normally retains the ground fabric in a condensed condition, but permits the fabric to stretch under tension. The rubber backing B also assists in holding the tufts in the ground'fabric and prevents them from coming out when the fabric is stretched.

Heretofore it was desirable to closely weave the ground fabric so as to hold the tufts in place. In accordance with the present invention it is desirable to use a relatively open weave in the ground fabric so that it can be condensed and rely upon the rubber backing B to retain the tufts inthe ground fabric as it is stretched and contracted. This elastic pile fabric is particularly well adapted for use in upholstery work where it will conform more snugly to the surface being covered than non-elastic pile fabric, and will also stretch to relieve strains thereupon. I

A loosely constructed textile fabric when treated in accordance with the present invention may be converted into an elastic fabric having a stretch considerably in excess of 100% of the stretch of the original textile fabric.

As various other modifications than those disclosed herein will occur to persons skilled in the art, it is not intended to limit the invention other than as required by the scope of the prior art and as set forth in the appended claims.

This application is a continuation in part of application Serial No. 69,302, flied March 17, 1936.

Having thus described our invention what we claim and desire to protect by Letters Patent is:

l. The method of making an elastic fabric comprising the steps of adhering a textile fabric to a stretched elastic surface with a rubber-containing fluid, releasing a substantial amount of tension on said elastic surface to permit it to contract and condense the fabric, converting the rubber containing fluid into an elastic medium of sufllcient strength to retain the textile fabric in the condensed condition, and removing said tex k 2,219,829 is condensed its thickness is increased to some tile fabric with the rubber adhered thereto from said elastic surface.

2. The method of-making airelastic fabric com-; prising the steps of stretching an elastic surface, adhering a textile fabric to the stretched surface with a latex adhesive, releasing a substantial amountof the tension on said elastic surface to permit it to contract and condense the fabric, converting the latex into an elastic medium of sumcient strength to retain the textile fabric in the condensed condition, and removing said textile fabric with the rubber derivedfrom said latex adhered thereto from said elastic surface.

3. The method of making an elastic fabric comprising the steps of applying a rubber-containing fluid to a textile fabric, stretching an elastic surface under tension, securing the fabric temporarily to said stretched surface by the rubber-containing substance on the fabric, releasing a substantial amount of the tension on the stretched surface to permit said surface to contract while the fabric is secured thereto to condense the fabric by forcing the threads thereof more closely together, treating said rubber-containing substance and thereby cause it to set to a solid condition so that it will yieldingly hold the fabric condensed, and then removing the fabric with the rubber adhered thereto from said surface.

4. The method of making an 'elastic fabric comprising the steps of applying a. rubber-containing fluid to a textile fabric, drying said rubber containing fluid to a tacky condition in which the rubber is substantially coagulated, stretching an elastic surface under tension,securing the fabric temporarily to said stretched surface by the dried tacky rubber-containing substance on the fabric, releasing a substantial amount of the tension on the stretched surface to permit said surface to contract while the fab ric is secured thereto to condense the fabric by forcing the threads thereof more closely together,

at least partially curing the rubber derived from said rubber-containing fluid so that it will yieldingly hold the fabric condensed, and then removing. the fabric with the rubber adhered thereto from said surface.

5. The method of making an elastic fabric comprising the steps of applying a rubber-containing fluid to a textfle fabric, introducing the fabric between a pair of surfaces at least one of which is stretched under that the fabric is gripped between said surfaces and is secured to the stretched surface by the rubbercontaining substance, releasing a substantial amount of the tension on the stretched surface to permit it to contract and condense the fabric secured thereto by forcing the threads of the fabric closer together, treating said rubber-containing substance to cause it to ,set to a solid-condition so that it will yieldingly hold the fabric condensed, and then removing thefabric with the rubber adhered thereto from said surface.

6. The method of making an elastic fabric comprising the steps of applying a rubber-containing fluid to a textile fabric, introducing the fabric between a pair of elastic surfaces stretched under tension so that the fabric is gripped therebetween, adhering said fabric by said rubber-containing substance to one of said surfaces, releasing a substantial amount of the tension on the surfaces to permit said surfaces to contract to condense the fabric held therebetween by crowding the threads of the fabric closer together, treating the rubber-containing substance to set it to a solid condition so that it will yieldingly hold the fabric condensed, and then removing the fabric with the rubber adhered thereto from said surface.

7. The method of making an elastic fabric which comprises applying latex adhesive to a textile fabric, adhering said textile fabric to a stretched elastic surface with said adhesive, releasing a substantial amount of the tension on saidsurface to permit it to contract and condense the said textile fabric and thereby placing the threads thereof extending in the direction of the condensation in a relaxed condition, converting said latex adhesive into an elastic medium of sumcient strength to retain the textile fabric in the condensed condition, and removing said textile fabric with the rubber deposited from the latex adhered thereto from said elastic surface.

8. The method of making an elastic fabric which comprises applying latex adhesive to atextile fabric, drying said latex adhesive to a tacky condition in which the rubber is substantially coagulated, adhering said textile fabric to a stretched elastic surface with said dried tacky adhesive, releasing a substantial amount of the tension on said surface to permit it to contract and condense the said textile fabric and thereby placing the threads thereof extending in the direction of the condensation in a relaxed condition, at least partially curing the rubber derived from said latex adhesive until it has sufllcient strength to yieldingly retain the textile fabric in the condensed condition, and removing said textile fabric with the rubber deposited from the latex adhered thereto from said elastic surface.

9. The method of making an elastic fabric comprising the steps of spraying a rubber-containing fluid on a textile fabric, spraying a coagulant thereupon, then adhering the fabric to a stretched elastic surface with the rubber containing fluid, releasing a substantial amount of the tension on the elastic surface to permit it to contract and condense the fabric by crowding the adjacent rows of threads forming the fabric more closely together so as to place the threads of the fabric forming a connection between said rows in a relaxed condition, treating the rubber-containing fluid to set it to a solid condition so that it will yieldingly hold the fabric condensed, and then removing the fabric with the rubber adhered thereto from said elastic surface.

10. The method of producing a two-way stretch. elastic fabric which comprises the steps of stretching a knitted fabric longitudinally to contract it transversely, then adhering the fabric to a stretched elastic surface with a rubber containing fluid, releasing a substantial amount of the tension on the elastic surface to permit it to contract and condense the fabric by crowding the adjacent rows of thread forming the fabric more closely together, converting the rubber containing fluid into an elastic medium to hold the fabric yieldingly in the condensed condition, and removing said fabric with the rubber adhered thereto from said elastic surface.

11. The method of making an elastic fabric comprising the steps of stretching an elastic surface in one direction without appreciably changing its dimension transverse thereto; adhering a textile fabric to the stretched surface with a rubber-containing fluid; releasing a substantial amount of tension on said elastic surface to permit it to contract along the lines it has been stretched, without any appreciable change in its dimension transverse thereto and thereby condensing the fabric; converting the rubber-containing fluid into an elastic medium of suflicient strength to retain the textile fabric in the condensed condition; and removing said textile fabric with the rubber adhered thereto from the elastic surface.

MERWYN C. TEAGUE. THOMAS G. HAWLEY, JR.

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