US2733498A - G hatay - Google Patents

Description

Feb 7; 1956 c. cs. HATAY METHOD OF FABRIC FINISHING TO"REDUCE SHRINKA AND IMPROVE THE FEEL AND HAND OF CLOTH Filed March 7, 1955 Feb. 7, ATAY C. G. H METHOD OF FABRIC FINISHING TO REDUCE SHRINKAGE AND IMPROVE THE FEEL AND HAND OF CLOTH Filed March 7, 1955 2 Sheets-Sheet 2 /NVENTOR CHARLES GEORGE H my A BVM h-w United States Patel-nt O METHD F FABRIC FINISHIN G T REDUCE SHRNKAGE AND IMPRVE THE FEEL AND HAND 0F CLOTH Charles G. Hatay, Manchester, Mass. Application March 7, 1955, Serial No. 492,436 1s claims. (ci. 26-185) The present invention relates to a method of finishing fabric, both woven and knit, to reduce shrinkage during subsequent washing and to improve the feel and hand of the cloth. It is applicable to fabric made from the various textile fibers, for instance, cotton, wool, rayon and other natural and synthetic fibers or mixtures thereof, and it may be used as part of the ordinary procedure of finishing such fabrics. It is particularly applicable to knit goods as to which, as far as I am aware, no practical method has been discovered by which the shrinkage may be greatly reduced.

vHeretofore,V a commonly employed method of reducing shrinkage has been to compress the goods while in a wet condition against a fiat surface, and while so compressed to dry them by the application of heat. As a practical matter this process is applicable only to cotton, linen and synthetic fibers of the same general nature, and while it reduces the subsequent shrinkage considerably, it is apt to give the cloth a polished, shinysurface and a less satisfactory hand and feel. This is probably due to the fact that the fibers composing the cloth are somewhat plastic in the presence of moisture and heat and are iiattened and polished and are pressed into each other thereby reducing the thickness of the cloth.

My invention is based on the discovery that if fabric while in a substantially lax condition is subjected to successive sharp localized impacts, shocks or blows and if the area on the other side of the cloth opposite to the area where each of said impacts is imparted is free from contact witha rigid surface at the time of said impact, the libers and strands composing the cloth are rearranged and repositioned, the cloth is thickened and some of the ends of the fibers are released from entanglement and brought to the surface and the hand and feel of the fabric is `improved butV that the surface of the fibers is not polished nor rendered shiny.

I have further discovered that if, during at least a part of the time during which wet fabric is impacted, it is simultaneously driedl and the Water content thereof is reduced below that necessary to saturate the fibers and maintain a molecular film of water thereon (about 25% moisture content of the fabric) the tendency of the fabric to shrink on being subsequently washed and dried is reduced and may even be largely eliminated, the residual shrinkage depending on the moisture content left in the fabric after completion of treatment andthe amount of impacting. Although the impacting may begin while the moisture in the cloth exceeds that necessary to saturate the fibers and maintain a molecular lm of water thereon, this amount of water being ordinarily about twenty-five percent of the weight ofthe bone dry cloth,it is not until after the water content has fallen Ybelow this amount that there is any substantial improvement in the reduction of shrinkage Vduring subsequent washing.

I have further discovered that by arranging the motion of the impactor in such a way that the resultant displacement of the fabric is in the direction of the desired ad- ,p 2,733,498 ce Patented Fei). 7, 1956 Vance, the fabric can be made to advance without pulling it or subjecting it to any substantial tension.

It is preferable that the area 0f each impact be as small as possible so that the amount of energy dissipated per unit of area shall be as large as possible, since, if applied over a large area, the result of the impact is chiey to push the cloth out of the path of the impacting member without the desired effect on the fiber structure.

The amount of rearrangement and repositioning of the fibers depends primarily upon the momentum of each impact, total number of impacts given to each unit area of the fabric, and the weight and mass of the fabric. The momentum of each impact depends chieiiy on the amplitude and rate of travel of the impactors while the total number of impacts given to each unit area depends also on the rate of travel of the fabric past the impactors. Different types of fabric require different amounts of energy to rearrange the fibers.

The following theoretical explanation which I believe to be correct may be helpful in understanding and practicing the invention but is not intended to limit it except as stated in the claims.

When moisture is applied to a fabric Whose fibers are moisture absorbent, the bers first absorb moisture and complete saturation is indicatedy by a molecular film of moisture on the surface of the fibers; thereafter as further water is applied the interstices fill up. The moisture in the interstices is conveniently called the entrapped moisture while that contained in the fibers themselves may be called the absorbed moisture. Thereafter when the fabric is dried the entrapped moisture is first removed, and afterward the absorbed moisture evaporates. If a wet fabric is impacted and simultaneously dried, and the impacting is stopped before the entrapped moisture is entirely removed, it is found that while the hand and feel is improved by the treatment, the shrinkage is reduced.

It is further found that the effect of impacting in reducing shrinkage increases as the drying reduces the moisture content, and is particularly noticeable as the point of complete dryness is approached.

The method embodying the present invention may be incorporated as one step in the ordinary procedure of finishing fabrics.

The invention will be fully understood from the following description taken in connection with the accompanying drawings.

Fig. l is a vertical section of the machine through which cloth which is being treated passes horizontally after it leaves the dryer and before it enters a machine for some subsequent treatment, as for instance, a tenter,

and spreader.

Fig. 2 is a section on line 2 2 of Fig. 1.

Fig. 3 is a vertical section of a machine like that of Fig. l except that the upper impacting members are omitted and the impacting wires are arranged in units, each unit being moved independently by a separate and independent driving means. These driving means are not shown but each of them is like the driving means of Figs. l and 2.

Fig. 4 is a vertical section of a machine like that of Fig. 3 except that it has upper impacting units in addition to lower impacting units. Each of these upper units move and are moved in the same way and by the same means as, but independently of, the units of Fig. 3.

Fig. 5 is a section on line 5-5 of Fig. 4.

Referring now to Figs. land 2, a web, i. e., a continuous length, of fabric is indicated at A. At 11 is indicated a dryer with the support rolls 12*12 and weight rolls 13-13 supported by festoons of the fabric A. In this dryer a portion of the water is removed from the web. The web is pulled through the dryer 11 by the rolls 22 and then passes into and through a machine, which is conveniently referred to as an impacting machine and which is designated B, in such a manner that while it is in the impacting machine, it is at all times slack and lax. This machine includes a series of taut wires 14 and 15 which are stretched between vertical arms 16 and 16. The arms 16 for the wires 14 are located on and extend 'upwardly from a floating plate or support 26, and the arm lo for the wires 15 are supported on and extend downwardly from another floating plate or support 17. The plates 26 and 17 are supported between upper and lower springs 1S and 19 so that the plates 26 and 17, and consequently the arms 16 and 16 and the wires 14 and 15 are free to move bodily as a unit in a generally circular path or orbit under impulses given to the plate by some convenient device. Rotating shafts 28 and 29 are carried in brackets 31 and Si) on the plates 26 and 17. Each shaft is rotated by a belt 33 and an electric motor 32 mounted on the respective plate, and each shaft carries on its ends eccentric weights 20. It is apparent that upon clockwise rotation of the lower shaft and its eccentrics and counterclockwise rotation of the upper shaft and its eccentrics, the eccentrics attached to shaft 2g cause shaft 28, plate 26, arms 15 and wires 14 to move bodily and in a clockwise direction along a generally circular path or orbit, as shown by the arrows, and the eccentrics attached to shaft 29 cause shaft 29, plate 17, arms 16 and wires 15 to move bodily and in a counterclockwise direction along a generally circular path or orbit as shown by the arrows. This causes the wires to strike the fabric a succession of sharp localized impacts or blows and to move it longitudinally through the machine to the right. The periodand amplitude of movement of wires 14 and 15 may be regulated by regulating the speed of the motor and tension on the springs 13 and 19 by screws 35. At 21V-21 is shown a pair of rolls which carry the slack web away from the impacting machine at a suiciently slower rate than rolls 22 feed it into the machine to account for the shrinkage of the cloth while it is in the machine. Rolls 21-21 do not pull the cloth through the machine so as to cause the fabric in the machine to be under tension; on the contrary they serve only to take up slack in the fabric and while conveniently employed may be omitted without material effect on the operation ofthe machine.

Each impact of the wires bats the lax fabric into space where, while it is still in a floating condition as a result of such impact, it is again subjected to succeeding impacts, much as `a tennis ball is kept in the air by repeatedly batting it upwardly with a tennis racquet. In other words the fabric is impacted while it is floating in space due to the next preceding impact. In the case of the lower impacting members, the fabric is batted upwardly and forwardly and caused to progress toward the outlet of the machine. Where both upper and lower impactors are employed, the fabric is repeatedly batted back and forth by and between the impactors and also progresses through the machine. Warm, dry air is blown through the machine by a suitable blower 24 and reduces the water content of the web as the treatment takes place. As can be seen from the drawings the fabric A is extremely billowy along its width and length and is in the air a large part of the time as it progresses through the machine.

At 25 is indicated a device for treating the web further, for instance, a tenter to stretch it laterally or for such other treatment that may be required. VSuch Vtreatment does not form a part of my invention.

The embodiment of Fig. 3 is similar to that of Figs. l and 2 except that (l) it has no top impactors, (2) the bottom impacting wires are arranged in three units 4'0, each unit having a plurality of impacting wires 14 attached to three cross bars 14a which are in turn attached to arms 16, and (3) each unit is driven independently and bodily along a generally circular path or orbit as shown by the arrows by independent driving means (not shown), each` of which is like the driving means of Figs.

1 and 2. That is, the arms 16 of each unit are attached to a separate, independent plate like plate 26 of Fig. 1, which is moved independently and bodily along a generally circular path or orbit by a separate shaft having eccentrics attached to the ends thereof, a separate set of springs and a separate motor which is arranged in the same manner as shaft 28, ecccntrics 20, springs 18, 19 and motor 32 of Figs. l and 2. However, any means for moving the units bodily in a generally circular or elliptical path or other orbit can be used. The units 40, as shown, are not synchronized and move independently of each other. However, they may be synchronized to move together or may all be attached to the same plate so that they all move together as in the case of the Wires 14 in Figs. l and 2. In the machine shown in Fig. 3 the lefthand unit, shown in full lines, is in its uppermost position while the middle unit, shown in full lines, is in its lowermost position and the right-hand unit, shown in full lines, is in an intermediate vertical position. The lowermost position and two intermediate position of the lefthand unit, the uppermost and two intermediate positions of the middle unit and the uppermost, lowermost and one intermediate position of the right-hand unit are shown in broken lines. The lax cloth batted upwardly and to the right by the right-hand unit falls onto a trough 41 from which it is taken up by rolls 21. As many units as desired can be used in series depending upon the amount of impacting desired.

The embodiment of Figs. 4 and 5 is like that of Fig. 3 except that top impacting units 42 eachY of which has a plurality of wires 14", cross bars 14h and arms 16" are provided opposite each bottom unit. Each of the top units has independent driving means to move it independently in a generally circular path or orbit as shown by the arrows. Each of these driving means are the same as those used to drive the lower units. In the drawing the left-hand upper and lower units are at their uppermost positions while the right-hand upper and lower units are in their lowermost positions. However, the upper units need not be synchronized in any manner with the lower units and can move completely independent therefrom. It is apparent that opposing units never come together and are at all times spaced from each other so that the fabric is batted back and forth between them while being advanced to the right. In other words, the area on the other side of the fabric opposite from the area where each of the impacts is given is free from contact with a rigid surface at the time of such impact so that the fabric is freely displaced. In effect the fabric is floating or in a floating condition.

The impacting machines and drying means shown in Figs. l to 5 are merely for the purpose of illustration, since any device which will give the fabric violent localized impacts may be employed. These machines are not claimed herein, since they will constitute the subjectv matter of another application.

I have found that cloth treated by my improved method will have a shrinkageV after subsequent washing and Vdrying less than one percent and that this shrinkage may be even as low as 0.2 percent. Cotton knit goods for underwear which have been subjected to the hereindescribed treatment were found to have a shrinkage after washing and drying of less than 5% or lower depending on the method of testing employed.

To determine the eifect of my novel method for reducing shrinkage,.four pieces of cotton knit goods suitable for underwear were treated as hereindescribed and then tested by the following procedure.

The four fabrics were cut to uniform length and treated twice by running in home type portable washing machine at 120 F. with .5% soap and given three rinses in water of F. (each washing for a thirty minute period). Each piece Was measured in'a straight but not stretched condition before laundering and between each laundering after being dried. The average measurement of the two verage Percent Average Percent kage Elongatlon Sample Stitch Length Width Length Width a- Rib 3.75 1.9 b Flat 0.7 3.75 c Rib 1` 875 1.3 d Flat 3.75 nil It is to be understood that the momentum, i. e., a function of the mass, speed and amplitude of movement of impacts should be great enough to produce the desired results but should not injure the structure of the fiber. In the practice of the invention, I have used impactors having amplitudes of movement varying from A to 2.3 inches and rates of movement from 5000 strokes a minute to 520 strokes a minute and have obtained satisfactory results. The amplitudes of movement, and the rates of impact will of necessity vary with the character of the fabric to be treated. In practice the fabric can enter the machine in a thoroughly wet condition, be dried as it passes the impactors and emerge from the machine in dry condition with a much improved hand and feel and a marked reduction in shrinkage, the amount of the reduction depending largely on the extent of the drying and impacting.

This application is a continuation-impart of application Serial No. 205,760, led January 12, 1951, and now abandoned.

I claim:

l. A method of treating a web of fabric comprising giving to the web, while it is freely floating in space ina substantially lax condition, sharp, localized impacts at a plurality of points along the surface thereof.

2. The method of claim 1 in which said impacts are imparted to said fabric in such a direction as to advance the fabric longitudinally.

3. The method of claim l wherein said web of fabric is batted into space by said impacts, and while it is in a floating condition, is again batted.

4. The method of treating a wet fabric which includes subjecting the same, while it is in a substantially lax condition, to successive sharp, localized impacts, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface at the instant of impact.

5. The method of treating a web of fabric which includes subjecting a wet web of said fabric at a plurality of relatively small areas therealong, while it is in a substantially lax condition and during drying thereof, to successive, rapidly repeated, sharp, localized impacts, the area in the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface at the instant of impact.

6. The method of treating a web of fabric which includes subjecting a wet web of said fabric at a plurality of relatively small areas therealong, while it is in a substantially lax condition and while it has a moisture content less than that of the absorbed moisture, to successive, rapidly repeated, sharp, localized impacts, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface at the instant of impact.

7. The method of finishing a web of fabric to reduce shrinkage and improve the feel and hand, which includes giving to a wet web of fabric at a plurality of relatively small areas therealong, during drying thereof and while it is in a substantially lax condition, successive, rapidly repeated sharp localized impacts, the water content of said fabric during at least a part of said drying and impacting being not more than that necessary to saturate, and maintain a molecular lm of water on the fibers thereof, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface during the time of said impact.

8. The method of claim 7 wherein said web of fabric is longitudinally conveyed in a selected direction by said impacts.

9. The method of fabric finishing to reduce shrinkage and improve the feel and hand, which includes giving to a wet fabric at a plurality of relatively small areas therealong, While reducing the moisture content of the fibers thereof and while it is in a substantially lax condition, successive, rapidly repeated, sharp localized impacts, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface during the time of said impact.

l0. The method of fabric finishing to reduce shrinkage and improve the feel and hand, which includes subjecting the surface of a wet fabric during drying thereof and While it is in a substantially lax condition, to successive, sharp localized impacts, the water content of the wet fabric during at least a part of said -drying and said irnpacting being not more than 25% of the dry weight of the fabric, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface during the time of said impact.

1l. The method of finishing a web of fabric to reduce shrinkage and improve the feel and hand, which includes wetting a web of said fabric to saturate, and include more than a molecular film of moisture on the fibers thereof, and thereafter during drying of the web of wetted fabric to a point below the amount required for said saturation and said iilm and while it is in a substantially lax condition, repeatedly giving the web of fabric at a plurality of relatively small areas therealong progressively successive, sharp localized impacts, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface during the time of saidimpact.

12. The method of claim l1, wherein said web is longitudinally conveyed in a selected direction by said impacts.

13. The method of fabric finishing to reduce shrinkage and improve the feel and hand, which includes giving to a wet fabric during drying thereof, and while it is in a substantially lax condition, successive, sharp, localized impacts, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface at the time of said impact, the water content of said wet fabric during at least a part of said drying and said impacting being not more than that necessary to saturate, and maintain a molecular film of water on the fibers.

14. The method of claim 13 wherein said fabric is longitudinally conveyed in a selected direction by said impacts.

l5. The method of finishing a web of fabric to reduce shrinkage and improve the feel and hand, which includes repeatedly giving a wet web of said fabric at a plurality of relatively small areas therealong, while it is being dried and while it is in a substantially lax condition, successive, sharp localized impacts, the area on, the other side of said fabric opposite to the area where each of said impacts are imparted being free from contact with a rigid surface during the time of said impact, the water content of said fabric during at least a part of said drying and said impacting being not more than 25% of the dry weight of the fabric.

16. A method of fabric finishing to reduce shrinkage and improve the hand and feel, which includes subjecting :rr-thoroughly wetted fabric at a plurality of relatively small areas therealong, during, drying thereof to a bone dry condition, and While it is in a substantially lax condition, to successive, rapidly repeated, sharp, localized im pacts, the area on the other side of said fabric opposite to the area where each of said impacts is imparted being free from contact with a rigid surface during the time of said impact, said impacts being imparted to said fabric in such a manner as to longitudinally advance said web in a selected direction. Y

17. A method of finishing a web of fabric to reduce shrinkage and improve the hand and feel, Ywhich includes repeatedly giving a Wet web of fabric at a plurality. of relatively small areas therealong, while it is being dried from a point at which it contains an amount of Water greater than the amount necessary to saturate, and form a film of moisture on the bers thereof to a point at which it contains an amount of water which is substantially less than that amount required to saturate, and form a film of moisture on said bers and while the web is in a substantially lax condition, successive, sharp, localized impacts, theY area on the other side of saidfabric opposite to the area where each of said impacts Yare* imparted being free from contact with a rigid surface .during the timeof saidxirnpact. l

18. The methodtof claim 17 Whereinsaid web is longitudinally conveyed in a selectedktdirection by said impacts.

References Cited in the iile of this patent UNITED STATES PATENTS 253,161 Doubleday Ian. 31, 1882 485,694 Haskell Nov. 8, 1892 1,181,789 Morley May 2, 1916 1,591,851 Macadam et al. July 6, 1926 1,741,755 Chase et al. Q Dec'. 31, 19,29 GObel 'Fell 2,187,543 Haskin Ian. 16, 1940 2,351,549 Schwartz Jan. 13, 1944 2,393,243 Franz V l Jan. 22, 1946

Claims (1)

1. A METHOD OF TREATING A WEB OF FABRIC COMPRISING GIVING TO THE WEB, WHILE IT IS FREELY FLOATING IN SPACE IN A SUBSTANTIALLY LAX CONDITION, SHARP, LOCALIZED IMPACTS AT A PLURALITY OF POINTS ALONG THE SURFACE THEREOF.

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