US2434111A - Method of manufacturing elastic fabrics - Google Patents

Description

1948. T. G. HAWLEY, JR., ET AL 2,434,111 I @METHOD OF MANUFACTURING ELASTIC FABRICS Filed Feb. 24, 1944 2 Sheets-Sheet 1 BYQVE 2 ATTORNEY Jan. 6, 1948. T. G. HAWLEY, JR., ET AL 2,434,111

' METHOD OF MANUFACTURING ELASTIC FABRICS Filed Feb. 24, 1944 2 Sheets- Sheet 2 ATTORNEY Patented Jan. 6, 1948 METHOD OF MANUFACTURING ELASTIC FABRICS Thomas G. Hawley, Jr., St. Paul, Minn., and Nicolai Timenes, Waterbury, Conn., assignors to United States Rubber Company, New York, N. Y., a corporation of New Jersey Application February 24, 1944, Serial No. 523,756

9 Claims.

This invention relates to an improved method of making an elastic fabric, by adhesively combining elastic material with an extensible layer of textile fabric, and particularly to such method wherein the elongation of the textile fabric in the finished product is increased uniformly throughout in one direction, as compared to its normal state, by gathering the opposite edges of the textile fabric, and stretching same in a direction transversely to such edges prior to combining the elastic material with the textile fabric.

It is known that textile fabric such as a knitted fabric when stretched transversely in the direction of its courses, and a fabric such as a biascut woven fabric when stretched transversely and diagonally of the threads, will contract in the loncedure the knitted fabric Was stretched transversely in the direction of the courses, so as to contract the fabric in the direction of the wales, and while so stretched the layer of fabric was combined with an elastic layer of rubber by adhering the rubber thereto.

The above process is described in United States Patent No. 2,004,110, gran-ted June 11, 1935, to P. H. Head. In that process provision was not made to permit the knitted fabric to contract freely and uniformly as it was being stretched transversely which is necessary in order to obtain the maximum elongation and uniformity of stretch in the finished elastic fabric. Although it is stated in the above mentioned patent that the treatment of the fabricmay be continuous there is no disclosure as to how the textile fabric may be continuously stretched transversely and the elastic material continuous but successively and simultaneously applied thereto. The problem of permitting the textile fabric to contract freely particularly arises when the fabric is processed continuously, as when it is stretched transversely on a tentering machine where the opposite edges of the fabric are held in a fixedposition along the diverging inelastic chains of the machine so 2 that it is restrained from contracting longitudinally when it is stretched transversely.

The process constituting the present invention is adapted to be carried out continuously and permits the textile fabric to contract freely and uniformly in one direction when it is stretched in the direction at right angle to the direction of contraction. The term textile fabric is used here in the sense that the fabric is capable of so stretching and contracting. The direction of the contraction of the fabric is referred to as the longitudinal direction and the direction at right angles thereto is referred to as the transverse direction. It is also to be understood that the term contraction means the longitudinal shortening of the fabric resulting from stretching it transversely. In accordance with the practice of the present invention, a transversely stretchable textile fabric is first gathered along its opposite longitudinal edges in an amount substantially equal to the desired longitudinal contraction of the fabric, which should be at least 15% of the normal finished length of such edges. The fabric is then stretched transverselybetween the edges, and although such edges may be held in a fixed position by the tenter frame, the fabric is free to contract longitudinally as it moves along the diverging sides of the tenter and is being stretched transversely. While the textile fabric is held in the transversely stretched condition, an elastic layer of material, such as for example, natural or synthetic rubber, or rubber composition or rubberlike material, or other elastic plastic, is adhered to and elastically combined with the fabric. The elastic material may be applied to the textile fabric in accordance with procedures heretofore used, such as by applying a coating of rubber or other plastic containing fluid to the fabric and thereafter drying and/or vulcanizing the solids deposited from. the fluid to form an elastic layer adhered to the fabric, or the elastic material may be calendered on the fabric, and in the case of a vulcanizable material, it may be subsequently vulcanized.

The operation of gathering the longitudinal edges of the textile fabric prior to stretching it in the transverse direction is an improvement over the prior process because by so doing the textile fabric is permitted to freely contract in the longitudinal direction and the fabric is thereby imparted greater extendibility and more uniform elongation throughout than was heretofore obtained, and the finished composite elastic fabric is provided with the same improved qualities. The gathering operationalso makes it possible to perform the process in a continuous manner on a tentering machine and thereby produce relatively long lengths of the elastic fabric without any seams.

The method practised in this invention will be described more fully in connection with the accompanying drawings, in which Fig. 1 is a plan view of an apparatus which is suitable for performing the method practiced in this invention;

Fig. 2 is a plan view of a fragment of a transversely extendible textile fabric showing one of its longitudinal edges, which has beenigathered on a sewing machine and stitched to hold the gathering in place;

Fig. 3 is a plan view of an apparatus capable of carrying out another form of the method;

Fig. 4 is a cross-section of a portion of the apparatus shown in Fig. 3, and illustrating the mechanism for gathering one of the longitudinal edges of the textile fabric; and

Fig. 5 is an end view of the apparatus shown in Fig. l'ta'ken on a line 5-45 of Figs. 3 and 4.

In the practice of the ;present invention by the use of the apparatus lfl, shown in Fig. l, the longitudinal edges H of the transversely stretchable textile fabric 12 are first uniformly gathered on a sewing machine, Or by any other suitable means, so -as to gather the edges as illustrated in Fig. 2. However, as shown in the latter figure only one of the edges -ll is shown as gathered by the stitches 13, it bein understood that both edges are to be gathered similarly. The gathered fabric may be wound on a roll [4, or may be draped in a box, and is led from the roll or box to the transverse stretching apparatus It, which is a tenter frame of a common type. The opposite edges H of the fabric are led into the left end of the machine, as viewed in Fig. l, and are secured to pins 115 carried by the chains "5 and 1 1 of the tenter frame T0.

The top reach of chains travel from the left to the right as indicated in Fig. l by the arrow A, and they diverge from another in such direction. As the fabric travels from the left end of the machine towards the right endfit is stretched laterally due to divergence of the chains, and that much of the original capacity of the fabric to stretch transversely is subtracted and added to the capacity to stretch longitudinally, thereby potentially increasing the longitudinal elongation of the fabric. Since the edges 'H of the fabric 12 are in a gathered state on the chains, they can contract without being restrained by the fixed position of the edges on the chains iii and H. The divergent course of the chains 55 and IT turns .at the hinged points 19 to about-a parallel course. During the travel of the fabric along such course, the elastic material "is combined with the stretched textile fabric.

As shown in Fig. 1, the elastic rubber containing fluid '20, from which the elastic material -to be combined with the fabric is derived, is applied by a doctor blade 2i to form a coating 22 which is set and converted into an elastic medium by a drier 23. The coating may also be Vulcanized 'while passing through the drier23, if desired. As the coated and dried composite elastic fabric 2 reaches the end of the tenter frame F8, it may be removed therefrom and wound on a roll 25. If desired the coating may be dried to a tacky condition and another layer of fabric may be adhered to the tacky coating which maybe subsequently vulcanized. I

The tenter frame chains '16 or ll are support- 3'4 which is driven by a pulley keyed to the shaft 32, and drives a pulley 36 keyed to a shaft 3? on which is aflixed the roll 25.

The distance between the parallel sides of the tenter frame 1 0 is adjustable and the diverging sides are pivoted at [9, and 38 for the purpose of controlling the transverse stretch of the fabric l2, and also for the purpose of accommodating different widths of the textile fabric l2 in its normal condition as it enters the feed end of the frame at the left. Circular brushes 39 containing relatively stiff bristles are mounted on the feed end of the "tenter frame over the tenter pins 15 for the purpose of pressing the edges of the fabric 12 on the pins 15 as .the fabric is led between the brushes and the pins. The brushes 39 are mounted on the shafts All which are rotatably mounted in brackets ll which carry the sprockets 2'6 and '2"! for the tenter chains l6 and "IT. The supporting structure for the brushes 39 is more particularly shown in Fig. 5 of the modification of the apparatus for carryin out the other form of the method practiced in this invention.

The other form of this method is carried out by the apparatus shown in Figs. '3 to 5 of the drawings. The method described in connection with these figures is similar to the method described in connection with Figs. 1 and '2, excepting that the longitudinal edges of the fabric are not stitch-gathered prior to applying the edges to the tenter pins, but on the other "hand the edges are gatheredand applied "In .a gathered condition to the "pins without the stitches.

As illustrated in Fig. 4 of the drawings, the

textile fabric 42 in its normal finished condition is led from a roll 43 whichis positioned over the tenter frame 44. As shown in Figs. '3, '4, and 5, the longitudinal edges '45 of the "fabric 42 are led into the gathering devices '36 positioned on each side of the feed 'end of the tenter frame 44. The gathering device on each -side'comprises two 'intermeshing gears 4-7 and 48 which are shown in detail in Figs. '4 and '5. The edges of the fabric pass between the "gears 41 and '48 and, as shown in Fig. '5, the margin 39 of the fabric extends outside of the gears and is positioned directly over the tenter pins 50. A slackness or gathering is imparted to the edges G5 by the gear teeth 5-1 and 52 of the respective gears 4'! and 48. As the extending marginal edges '49 are pressed into contact with the traveling tenter pins 5'0 on the ten ter :chains .53 by the gear M, the bristle brushes 54 positioned directly over the pins 50 press the :edges t!) *on to the pins so as to firmly secure the gathered edges thereto. As will be noted in :Fig. 4, :as the fabric passes from the :brushes 54, the marginal edges'49 are provided with gathers .or folds between th pins 50.

The tenter chains 53 are constructed and driven in the manner described with reference to Figs. 1 and 2. As the fabric4'2 is carried in the direction of the arrow 'B by the divergent course of the chains 53, it is stretched laterally between its edges i5, which are secured to the pins '50. After the fabric reaches the parallel course 51 of the to which the tenter pins 50 are affixed.

Brackets 62 are secured to each of the channels 58 of the tenter frame at the feed end for the purpose of supporting the ends of the channels and the tenter chain sprocket 63. The sprocket 63 is mounted on a shaft 64 which carries a sprocket 65 and drives a chain 65 which, in turn, drives a sprocket 61 which is keyed to a shaft 68. The shaft 68 is mounted in the bracket 62 and the gathering device gear 48 is mounted on the shaft 68 and drives the gathering mechanism.

The gathering device gear 41 is mounted on a stub shaft 69 which is rotatably mounted in an overhanging arm of the bracket 62. The bristle brushes 54 are mounted on stub shafts H which rotate idly in an arm 12 of the bracket 62.

While the preferred forms of this method have been described herein, it will be understood that changes in the details as described may be made without departing from the spirit of the invention and the scope of the appended claims.

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

1. The method of making elastic fabrics comprising the successive steps of uniformly gathering up the opposite edges of a textile fabric, uniformly stretching said fabric transversely to and between said edges by gradual increments until the fabric has been contracted in the direction of the gathered edges, and rendering said fabric elastic by adhesively combining elastic rubber containing material with said textile fabric while said fabric is so stretched.

2. The method of making elastic fabrics comprising the successive steps of uniformly gathering up at least 15% of the normal length of the opposite edges of a textile fabric in relatively small gathers, uniformly stretching said fabric transversely to and between said edges by gradual increments until the fabric has been contracted in a lengthwise direction in an amount substantially equal to the amount said edges were gathered up, and rendering said fabric elastic by adhesively uniting an elastic layer of rubber containing material to said textile fabric with an elastic bond while said fabric is so stretched.

3. The method of making elastic fabrics comprising the successive steps of uniformly gathering up at least 15% of the normal length of both of the longitudinal edges of a textile fabric, uniformly stretching said textile fabric transversely to said edges by gradual increments until the said textile fabric has been contracted in the direction of said edges in an amount substantially equal to the percentage of the gathering, applying an adhesive rubber containing liquid to said transversely stretched fabric, and converting said liquid into an elastic medium while said fabric is so stretched.

4. The method of making elastic fabrics comprising the successive steps of uniformly gathering up at least 15% of the normal length of both of the longitudinal edges of a textile fabric which is adapted to contract in the direction of said edges when stretched transversely thereto, uniformlystretching saidtextile fabric transversely .age of the gathering of the longitudinal edges, :applying an adhesive rubber containing liquid to said transversely stretched fabric, and drying said liquid sufficiently to convert it into a coherent elastic layer while said fabric is so stretched.

5. The method of making elastic fabrics comprising the successive steps of uniformly gathering the longitudinal edges of a transversely stretchable and, longitudinally contractable textile fabric until the gathered lengths of saidedges are less than of their normal length, uniformly stretching said textile fabric transversely by gradual increments until the textile fabric has been contracted in a lengthwise direction sufficiently to smooth out the gathering in the central portion of the textile fabric, coating the textile fabric with an adhesive rubber containing liquid while it is transversely stretched, and converting the liquid into an elastic medium.

6. The method of making elastic fabrics comprising the successive steps of uniformly gathering the longitudinal edges of a transversely stretchable and longitudinally contractable textile fabric until the gathered lengths of said edges are less than 85% of their normal length, uniformly stretching said textile fabric transversely by gradual increments until the textile fabric has been contracted in a lengthwise direction sufficiently to smooth out the gathering in the ce tral portion of the textile fabric, coating the textile fabric with an adhesive rubber containing liquid'while it is transversely stretched, and drying said liquid and vulcanizing the rubber so as to convert the liquid into an elastic medium.

7. The method of making elastic fabrics comprising the successive steps of introducing an initial longitudinal slack in a transversely stretchable textile fabric, by uniformly gathering the longitudinal edges of said fabric so that the athered length is less than 85% of its normal length, stitching said edges to retain them in said gathered condition, uniformly stretching said textile fabric transversely by gradual increments until the textile fabric has been contracted in the lengthwise direction in an amount substantially equal to the amount said edges were gathered, and rendering said fabric elastic by adhesively uniting an elastic layer of rubber containing material to said transversely stretched textile fabric with an elastic bond.

8. The method of making elastic fabrics comprising the successive steps of uniformly gathering up at least 15% of the normal length of both of the longitudinal edges of a textile fabric which is adapted to contract in the direction of said edges when stretched transversely thereto, uniformly stretching said textile fabric transversely by gradual increments until the said textile fabric has been contracted in the direction of said edges in an amount substantially equal to the percentage of the gathering of the longitudinal edges, applying to the transversely stretched fabric a rubber containing liquid, and drying said liquid to convert the residue into an elastic layer adhesively united to said textile fabric whil it is so stretched.

9. The method of making elastic fabrics comprising the successive steps of uniformly gathering up the longitudinal edges of a textile fabric, and thereafter continuously moving said fabric REFERENCES CITED The "folluwing references are of record in fi-he file of this patent:

Ntrmber Nmriber UNITED STATES Name 'Da'te I Head June '11, 1 935 fiawley June 13.11939 Teague 'Feb.25, 1 941 FOREIGN PATENTS Country Date Germany 001;.2'6, 193-8

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