US3115693A

US3115693A - Process of making a knitted fabric

Info

Publication number: US3115693A
Application number: US812215A
Authority: US
Inventors: Robert M Chandler
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1959-05-11
Filing date: 1959-05-11
Publication date: 1963-12-31
Anticipated expiration: 1980-12-31
Also published as: BE590712A; GB898819A

Description

Dec. 31, 1963 R. M. CHANDLER 3,115,593

PROCESS OF MAKING A KNITTED FABRIC Filed May 11, 1959 INVENTOR ROBERT M. CHANDLER United States Patent 3,115,693 PROCESS OF MAKWG A KNITTED FABRIC Robert M. Chandler, Wiimington, Dela, assignor to E. I. du Pont de Nemonrs and Qompany, Wilmington, Eek, a corporation of Delaware Fiied May 11, 1959, Ser. No. 812,215 8 flairns. (U. 23-72) This invention relates to novel knitted fabrics having woven-like characteristics and to a process for preparing same.

In the past, knitted fabrics have found their way into certain end uses which are dependent on a particular combination of physical properties and aesthetics peculiar to this fabric construction. The same has been true of Woven fabrics which have normally found their way into different end uses because of a different set of properties inherent in the woven construction. Knitted fabrics are too limp for some uses; they have a high degree of stretch, and a high tendency to bag. Woven fabrics need improvement in their wrinkling resistance. Present day costs of weaving are greater than those of knitting. Therefore, it has been felt desirable to develop a fabric having a combination of properties which can be used in a greater variety of applications and can be manufactured at lower cost.

It is an object of this invention to provide in the same fabric a combination of the more desirable characteristics in knitted and woven fabrics. More particularly it is an object to provide light weight knitted fabrics which closely simulate the aesthetics of woven fabrics. A further object is to provide a process for preparing novel knitted fabrics having woven-like characteristics. A fur ther object is to provide knitted fabrics which have outstanding shape retention, stability to stretching and shrinking and outstanding resistance to wrinkling during wear and laundering compared with woven fabrics of equivalent weight. Other objects will appear hereinafter.

The above objects are accomplished by providing a novel stretch resistant knitted fabric composed of at least 50% by weight synthetic organic linear polymeric filamentary material, said fabric having not more than about 15% stretch in the width and length directions. The invention also covers a process for preparing said novel stretch resistant fabric by the steps comprising selecting two feed yarns, each of which is composed of at least 50% by weight of synthetic organic linear polymeric filamentary material and each of which has a minimum residual linear shrinkage of at least 10%, feeding the first yarn into a single needle bed circular knitting machine to form a course of plain stitches, feeding the second yarn into said machine behind the first yarn to form a knitted greige fabric of tight construction having the second yarn in a laid-in configuration across the width of the fabric, subjecting the resulting greige fabric to conditions sufiicient to shrink the yarns, and finishing the fabric under conditions such that a fabric is obtained having not more than stretch in either direction. Preferably the process comprises selecting the said two feed yarns and knitting said greige fabric under conditions such that the tightness factor (T), as defined hereinafter, of the greige fabric is at least 1200. Optionally, it may be desirable to add another finishing step to the preparation of the fabric involving the application of a fiber bonding or coating composition in order to improve the final stiffness, liveliness, and handle of the fabric and improve the stretch resistance.

The filamentary material used in making the feed yarns for the knitting machine may be composed of either staple fibers or continuous filaments. The spun feed yarns or continuous filament feed yarns should be composed of at least 50% by weight of synthetic organic linear polymers. Examples of such highly polymeric fiber forming materials include polyamides such as poly(hexamethylene adipamide), poly(hexamethylene sebacamide), polycaproamide, and copolyamides, polyesters, and copolyesters such as condensation products of ethylene glycol with terephthalic acid, ethylene glycol with a 10 mixture of terephthalic/isophthalic acids, ethylene glycol with a 98/2 mixture of terephthalic/S-(sodium sulfo)- isophthalic acids, and trans p-hexahydroxylylene glycol with terephthalic acid, polyacrylonitrile, copolymers of acrylonitrile with other monomers such as vinyl acetate, vinyl chloride, methyl acrylate, vinyl pyridine, sodium styrene sulfonate, terpolymers of acrylonitrile/methyl acrylate/sodinm styrene sulfonate made in accordance with US. Patent 2,837,501, vinyl and vinylidene polymers and copolymers, polycarbonates, polyurethanes, polyesteramides, poiyethylenes, polypropylenes, fiuorinated ethylene polymers and copolymers, composite filaments such as, for example, a sheath of polyamide around a core of polyester as described in the copending application of Breen, S.N. 621,443, filed November 9, 1956, now abandoned and two acrylonitrile polymers differing in ionizable group content spun as a sheath and core as described in the copending application of Taylor, S.N. 771,677, filed November 3, 1958, now US. Patent 3,038,- 237, acrylonitrile polymer and copolymer fibers having a linear fiber shrinkage of 35% or more, and the like. For the purpose of this invention cellulose and cellulose derivative yarns are not to be construed as being included in the term synthetic.

The knitted yarns may be composed of either 100% of the said synthetic organic linear polymeric filamentary materials or they may be composed of a mixture of at least 50% of same with minor amounts of other filamentary material. The fibers or filaments present in the yarn in minor amounts may be composed of cellulose derivatives such as cellulose acetae, cellulose triacetate, regenerated cellulose, and the like or they may be composed of natural fibers such as cotton, wool, silk and the like. The yarns may be made from a mixture of two or more synthetic organic linear polymeric filamentary materails or they may be made from a mixture of said materials with one or more natural and/or cellulosic fibers or fiiarnents. The fibers and filaments making up the yarns may be either crimped or uncrimped, bulked or unbulked, or drawn or undrawn. Typical bulked yarns which may be used include Taslan textured yarn, Banlon, Saaba, Fluflon and the steam bulked yarns claimed in the co pending application of Breen and Lauterbach, S.N. 772,- 475, filed November 7, 8, now abandoned.

The preferred stitch construct-ion employed in knitting the greige fabric is basically a modification of a plain jersey construction. This construction is obtained by knitting an alternating course of plain stiches from the first yarn with a course of missed and tucked stitches from the second yarn. The course of missed and tucked stiches has the eifect of placing a laid-in yarn across the width of the fabric to impart stabilization to transverse stretching. The laid-in yarn or second feed yarn introduced to the knitting machine may be composed of the same filamentary material and may have the same residual linear shrinkage as that of the first feed yarn, or the two feed yarns may have different amounts of shrinkage and be composed of different filamentary materials. The second or laid-in yarn is important in the operation of this invention because it carries the major stress exerted in the widthwise direction of the fabric in the later finishing steps of the process. This laid-in stabilizing yarn actually contributes to reduction of the widthwise stretch provided the greige fabric is properly finished. The two feed yarns may be of the same or different deniers.

Any single needle bed circular knitting machine may be used to carry out the invention. Conventional satisfactory machines are illustrated on pages 20, 21, and 23 of Lester Mishcon and Abraham Abrams book entitled Pattern Wheel Designing for Circular Jersey Knitting Machines, (1949) published by Supreme Knitting Machine Co., Inc., Ozone Park, N.Y.

There are three yarn parameters, interdependent upon each other, which are important in obtaining a tight construction in the knitted greige fabric. These parameters are for each yarn (A) the length of yarn in the greige fabric, (B) the residual linear shrinkage of the yarn and (C) the denier of the yarn. As a guide for obtaining satisfactory tightness in the knitted greige fabric which will lead to fabrics that are inherently stretch resistant and woven-like, there may be used the following formula which relates the tightness (T) of the greige fabric with the three yarn parameters A, B, and C as follows:

(meters of yarn/yd?) (yarn denier in grams) (percent yarn shrinkage) stitches/foot of feed yarn 3 ft./yd. The length A is determined separately for each feed yarn in meters per square yard, then the two lengths added together to obtain the total length for use in the tightness formula. The average of the two yarn shrinkages and two yarn deniers are used in the formula. This tightness formula has been derived for one type of stitch construction in a circular knitted fabric, which is used in Examples IV, wherein plain courses are alternated in single succession with laid-in courses of missed and tucked stitches arranged in a 1X1 configuration. Each successive laidin course has missed and tucked stitches in different wales from the arrangement in the preceding laid-in course. The missed and tucked stitches in each laid-in course alternate in single succession. If the tightness factor T has a value greater than 1200, the greige fabric will yield improved woven-like knitted fabrics after being properly shrunk and finished. Greige fabrics prepared under conditions such that the tightness factor (T) has a value less than 1200 will result in finished fabrics having poor stretch resistance and a high degree of differential stretch between the length and width directions.

The tightness factor (T) for the fabric in each of the examples to appear hereafter is listed below:

Example: T value I 1940 II 1720 III 975 (unacceptable) IV a- 2.120 V 1670 To exemplify the use of the tightness formula, Example I produces a fabric wherein T is 1940. This fabric employs, for both feed yarns, a high number of stitches/in. (i.e. 750), a yarn denier of 266 and a yarn shrinkage of 12%. The number of stitches per foot for the plain and laid-in yarns is 80 and 169', respectively. Unacceptable fabrics are produced by lowering any one of the three variables as:

If shrinkage reduced to 6%, T=970 If greige stitches/in. are 350, T:900 If yarn denier is 137, T: 1000 In using the tightness formula given above it has been found that the shorter the length of laid-in yarn introduced per square yard of fabric in the width direction, the higher must be the residual yarn shrinkage in order to provide a tightness factor of at least 1200, and thereby yield satisfactory stretch resistance in the finished fabric. The preferred yarn counts are equal to or larger than those normally used for the machine gauge employed. Typical values of the yarn parameters in making the preferred fabrics of this invention when knitting on a 22 cut Supreme ROF circular knitting machine, include use of between 16 and 24 needles per inch, and preferably 20-24 needles per inch, when using 15s to 30s cotton count yarns, with yarn deniers preferably 150400, although the denier may vary over a range of 50 to 5000. The staple fibers or continuous filaments employed in spinning the two feed yarns must be selected so that each yarn posesses a linear residual shrinkage of at least 10%, and preferably from 15% to 30% or more. The exact amount of residual shrinkage in the yarn will be dependent upon the length of the yarn per square yard of fabric and the yarn denier in accordance with the tightness formula. The residual shrinkage in the yarn may be developed by spinning the yarn from synthetic organic linear polymeric filamentary material having high shrinkage, or the minimum residual yarn shrinkage may be developed by spinning the yarn from a mixture of two or more fibers or filaments having differential amounts of shrinkage. It is preferred to construct the yarn from a mixture of filamentary materials having differential amounts of shrinkage in order to obtain maximum bulk and cover in the final finished fabrics. The filamentary material having different amounts of shrinkage may comprise two or more fibrous materials having different amounts of high shrinkage or may comprise two or more fibrous materials some of which have essentially zero shrinkage and others of which have high amounts of shrinkage.

The linear residual shrinkage of all yarns referred to herein is determined by the following procedure:

The linear shrinkage of a single end loop of yarn is determined by making a single loop of yarn by knotting together the ends of a to cm. length of yarn. The loop of yarn is then measured by placing it over a hook at the top of a meter stick and hanging a hooked weight from the looped yarn using a tension of 0.1 gram per denier. The length of the loop is then read using the top surface of the hooked weight as the bottom of the loop. The loop(s) are then wrapped securely in cheesecloth and boiled in water for 30 minutes using a small amount of detergent. The package is removed from the bath, rinsed, centrifuged and dried and the loops hung up to condition. They are then remeasured using the same technique as before and recorded to the nearest 0.1 cm. The percent shrinkage is then calculated as follows:

Percent shrinkage X 100 where:

In addition to the preferred stitch construction of greige fabric for which the above tightness formula has been developed, other types of circular knitted constructions in the greige fabric may be employed using the second yarn in a laid-in stabilizing construction. Examples of these other types of construction include the following:

(A) Combinations of miss and tuck stitch courses a1- ternating or combined with plain knit courses.

(1) 1 2 (one tucked, two missed or welt stitches).

This construction may be formed by knitting a course of plain stitches on a circular knitting machine alternating with a course of stitches composed of a sequence of one tucked stitch and two missed (or welt) stitches to complete the course. Any multiple of feed yarns for these two types of courses may be used to form the fabric.

(2) 1 3 (one tucked, 3 missed stitches).

(3) 1 4 (one tucked, 4 missed stitches).

(4-) Random tucking and missing in laid-in course.

(5) Tuck and miss courses arranged in other than an alternating sequence with plain courses.

(B) Combinations of miss and knit stitches alternating or combined with plain courses.

(1) 1X1, 1X2, 1X3, and 1 4 knitted and missed courses.

(2) Courses of random knitted and missed stitches, providing the ratio of missed/knitted stitches is equal to or greater than 1 and preferably 2/1.

(3) Knitted and missed courses arranged in other than alternating sequence with plain courses.

(C) Combinations of knitted and tucked stitch courses alternating or combined with plain courses.

(1) 1 1, 1X2, 1 3, 1 4 knitted and tucked courses.

(2) Courses of random knitted and tucked stitches providing the ratio of tucked/knitted stitches is equal to or greater than 1 and preferably 2/ 1.

(3) Knitted and tucked courses arranged in other than alternating sequence with plain courses.

(D) Combinations of A, B, and C with one another to form patterns, provided that the number of plain knitted courses does not exceed more than /2 of all the courses knitted.

After production of the knitted greige fabric, this greige fabric is then subjected to conditions to shrink the yarns. The shrinkable yarns may be shrunk and/or bulked by any one of a number of conventional well-known methods, depending upon the particular composition of the fibrous material in the yarn. Such methods include exposure to boiling water, steam, heating in dry air or other inert atmosphere, exposure in molten metal or salt baths, exposure to aqueous or organic solutions containing chemicals which swell the fibrous material, and the like.

The last step in the process involves finishing the fabric after shrinkage under conditions which produce a final fabric having preferably equal stretch in both directions but having no greater stretch than 15% in each direction. This produces a knitted fabric with unconventional propperties since most knitted fabrics have a preferential stretch of a high degree in the widthwise direction. A preferred method of accomplishing the last finishing step is to subject the fabric either wet or dry on a pin tenter or other suitable holding means to an overfeed in the lengthwise direction while heating to a temperature of at east 200 F., while simultaneously stretching the fabric in the widthwise direction. The preferred range of stretch and overfeed is from 5% to 15% depending upon the method of shrinking the fabric. The fabric after this'final finishing step should have a stretch in both directions not greater than 15 and preferably less than in order to achieve all of the desirable objects of this invention. Other conventional finishing treatments may be given the fabric at this stage, including, for example, napping, shearing, fulling, needle punching, scouring, dyeing, semidecating, and the like.

The optional step of applying a fiber bonding or coating composition to the fabric after the stretch equalization finishing step in many cases further improves the woven-like characteristics and aesthetics of the knitted fabrics. This optional bonding step may be accomplished by applying to the fabric any of the well-known polymeric finishes in aqueous or organic media. Examples of these include resins such as ureaformaldehyde resins, melamine-formaldehyde resins, phenolformaldehyde resins, polyvinyl chloride and polyvinyl acetate resins, polyacrylic and polymethacrylic acid ester resins, elastomer compositions such as neoprene, styrene/butadiene synthetic rubber, butadiene/acrylonitrile synthetic rubber, polyurethane elastomers, and the like. A particularly valuable fiber bonding composition for application to the knitted fabrics of this invention is that described by R. A. Miller in copending application S.N. 794,813, filed February 24, 1959, now US. Patent 3,053,609. This fiber bonding composition comprises applying a one-phase liquid solution composed of a liquid medium, a latent fiber solvent soluble or miscible with said liquid medium and an inert extender soluble or miscible in said liquid medium, said solution being capable of conversion to a multi-phase system upon insolubilization of the inert extender, one phase of said system being a latent solvent for the fiber.

The following test procedures were employed in determining the physical properties of the fabrics reported in the examples.

The same test is employed for measuring both the stretch resistance and bagging tendency of a fabric. The stretch resistance is determined from the percent elongation or percent stretch in this test. The bagging tendency is reported as being a measure of the unrecovered tensile strain of the fabric in percent in both the length and width directions. Ten specimen pieces, each 4" x 8" are cut from a sample fabric. Five of the specimens are cut with the long dimension parallel to the wales and five are cut with the long dimension parallel to the courses of the fabric. A sample is placed in an Instron Tensile Tester at a 3-inch gauge length so that a slight amount of slack is left in the specimen. The fabric is then elongated at a rate of 16%%/min. to the load of 1,000 grams. After elongation, the load is removed at the same rate (16 /s%/min.) and the fabric is allowed to recover for 1 minute. The test specimen is then elongated at the same rate to a load of grams. The percent elongation is then determined from the first load elongation curve. The unrecovered tensile strain (bagging) is determined from the increase in specimen length after loading and unloading expressed as a percentage of original specimen length where the crosshead speed is 0.5 in./min. and the original specimen length is 3".

The dimensional stability of a fabric is determined by measuring the amount of shrinkage or elongation in each direction after five standard launderings. For determining dimensional stability, swatches of fabric two feet square are cut from a sample fabric. The corners of an 18-inch square are marked on the 2' x 2' fabric, after lining up the marking square parallel to the warp and fill. The fabrics are then laundered in a domestic washing machine and tumble dried five times. After laundering the change in dimensions of the hatch marks is measured and reported as percent shrinkage or percent elongation calculated as follows:

The wash-wear wrinkling rating of a fabric is determined on a fabric after laundering. Swatches of fabric 2 feet square are cut from a sample fabric. The fabrics are then laundered in a domestic washing machine having an automatic cycle and removed before the final spin rinse portion of the cycle. The swatches are then hung up to drip dry. After drying, the fabrics are evaluated using a method and rating scale described in Du Pont Technical Information Bullet X83, March 1958, Test Methods to Determine Wash and Wear Properties. This method employs a scale in which a rating of 5.0 is equivalent to no visible wrinkling and thus no ironing needed, and where a rating of 1 is given a fabric which is badly wrinkled.

In the drawing the single figure represents an enlarged view of the arrangement of the stitches in the fabric of the present invention. The laid-in course is added to the conventional wales and courses as shown in the hatched yarn. This laid-in thread is tucked in as shown in one Wale, missed; i.e., not tucked in in the next and then again tucked in in the third Wale. As described above such an arrangement of stitches is designated as 1 l. If two wales are missed so that the laid-in course is tucked in Wales 1 and 4, the arrangement is designated as 1x2, etc.

The following examples illustrate specific embodiments of this invention without intending to limit same. All parts are by weight unless otherwise specified.

7 EXAMPLE I A fabric was knitted on a 22-cut Supreme ROE circular knitting machine from a 20.9 singles cotton count yarn having 12.6 turns per inch Z twist. The yarn is composed of by weight 35% 4 /2 denier, 2 /2 inch staple length acrylonitrile polymer fiber having a residual linear shrinkage of 17%, 35% of 2 denier, 2% inch staple length of the same acrylonitrile polymer fiber having essentially no residual linear shrinkage (0.3%), and 30% of 64/70s grade wool. The linear shrinkage of the yarn was 12.2%. This yarn was spun from a stock blend of fibers On a modified cotton spinning system. A stabilized structure was knitted at a construction of 34 courses and 22 wales per inch in a configuration consisting of alternating courses of plain stitches and courses of missed and tucked stitches (i.e., laid-in yarns simulating the filling of a woven fabric). The fabric was subjected to a standard fulling and dyeing treatment in a Beck at the boil, which treatment resulted in a shrinkage of 8.8% in the length direction and 25 in the width direction of the fabric. The fabric was then dried open width on a pin tenter frame, then mapped, sheared, and semi-decated. The resulting fabric was divided into two parts. The first sample was padded with a bonding composition using 50 lbs. per square inch pressure in the padding operation. The bonding composition consisted of a solution of 1% polyethylene oxide (Polyox WSR 301) and 2.5% sodium thiocyanate in water. The wet pickup on the fabric was 161%. The bonded fabric was Beck scoured to remove the chemicals in the bonding composition, dried on a pin tenter frame and given a final semi-decating treatment. The bonded and unbonded samples of fabric both resembled a woven flannel type fabric in cover and handle and had the following properties:

Bonded Fabric Unbonded Fabric Property EXAMPLE II This example illustrates the preparation of a light weight woven-like knitted fabric. The fabric was knitted on the same circular knitting machine as that described in Example I from a 25.7 singles cotton count yarn having 16.4 turns per inch 2 twist. The linear shrinkage of the yarn was 15.8%. The yarn was composed by weight of 35% 4 /2 denier, 1 /2 staple acrylonitrile polymer fiber having a residual linear shrinkage of 17%, 40% of three denier, 1% inch staple of the same acrylonitrile polymer fiber having essentially no residual linear shrinkage (0.3%), and 25% of three denier, 1%; inch staple regenerated cellulose fiber. A stabilized structure was knitted at a construction of 30 courses and 21 wales per inch in a configuration consisting of alternating courses of plain stitches and missed and tucked stitches. The fabric was then given a standard treatment of fulling and dyeing at the boil in a Beck, which treatment resulted in 5% lengthwise shrinkage and 25% widthwise shrinkage of the fabric. The resulting fabric was dried open width on a pin tenter frame, napped, sheared, and semi-decated. The fabric was subsequently stabilized on a pin tenter frame by stretching it while wet 17.5% in wi th and overfeeding it in length by 11% at 250 F. The resulting fabric exhibited a high degree of stretch resistance and, thus, much more resembled a woven fabric than a knitted fabric in its stretch characteristics. The fol- 0 lowing properties characterize the fabric before and after the stretch and cverfeeding stabilization step:

EXAMPLE III This example illustrates the criticality of using a yarn having a minimum of at least 10% residual linear shrinkage in obtained fabrics having the superior properties of this invention. In other words this example illustrates the preparation of a fabric using conditions outside the scope of this invention. This fabric was knitted on the same circular knitting machine as that described in Example I from a 20.8 singles cotton count yarn having 13.4 turns per inch Z twist. The yarn had a residual linear shrinkage of 6.4%. The yarn was composed by weight of 35% 4 /2 denier, 2 /2 inch staple acrylonitrile polymer fiber having a residual linear shrinkage of 0-3% 35% 2 denier, 2 /2 inch staple acrylonitrile polymer fiber having a residual linear shrinkage of 03% and 30% of 64/ 70s grade wool. This yarn was spun from a stock blend of fibers on a modified cotton spinning system. The fabric was knitted at a construction of 32 courses and 22 Wales in a configuration consisting of alternating courses :of plain stitches and courses of missed and tucked stitches. The fabric was then given a standard treatment of fulling and dyeing in a Beck at the boil, which treatment resulted in a shrinkage of 16% in width direction and elongation of 11% in the lengthwise direction of the fabric. The fabric was then dried open width on a pin tenter frame, napped, sheared, and semi-decated. The resulting fabric was lean in cover and still possessed a significant amount of stretch as well as a particularly high degree of differential stretch in width and length directions. The fabric possessed the following properties:

Property Weight oz./60yd 10.0 Percent stretch:

Wale direction 7.1

Course direction 31.2 Percent shrinkage:

Wale direction -6.6

Course direction +2.7 Bagging tendency:

Percent length 0.8

Percent width 3.2

EXAMPLE IV A fabric was knitted on the same circular knitting machine as that described in Example I from a 1/32 worsted count yarn having 11.2 turns per inch. The yarn had a residual linear shrinkage of 21.4%. This yarn was composed of a blend by weight of 40% of 4 /2 denier acrylonitrile polymer fiber having a residual linear shrinkage of approximately 22%, 40% of 3 denier acrylonitrile polymer fiber having 03% residual linear shrinkage and 20% of fine wool. The yarn was prepared by blending Turbo-Stapler processed acrylic fiber tow with wool top. A stabilized structure was knitted at a construction of 25 courses per inch and 21 wales per inch (greige weight, 6.8 oz./60" yards) in a configuration consisting of alternating courses of plain stitches and missed and tucked stitches. The fabric was then given a standard treatment of scouring and dyeing at the boil in a paddle dyer, during which treatment the fabric shrank 35.4% in length and 12% in Width. The resulting fabric was dried open width on a pin tenter frame, napped, and then sheared. The fabric was then stabilized by drying on a pin tenter frame using 10% overfeed in the length direction and 12% stretch in the width direction. The fabric was then divided into two parts. One sample was padded with a bonding solution of 3% polyethylene oxide (Polyox WSR 35) and 4% sodium thiocyanate in water. The wet pickup on the fabric was 187%. The bonded fabric was then dried by pin tentering at 250 Beck scoured at 110 F., softened in hand by application of a standard 1.5% commercially available softener (Cerenine HC) in the Beck bath, dried on a pin frame at 250 F. and finally semi-decated lightly. The resulting bonded fabric possessed a full bodied aesthetically appearing hand together with moderate surface cover and flannel-like characteristics. The fabric possessed the following properties:

Weight oz./60 yd 10.9 Percent stretch:

Wale direction 6.9 Course direction 3.7 Percent shrinkage:

Wale direction 1.3 Course direction 1.3 Wash-wear wrinkling rating 3.4 Bagging tendency:

Percent length 0.5 Percent Width 0.2

EXAMPLE V A fabric was knitted on the same circular knitting machine as described in Example I from a 25.2 singles cotton count yarn having 14.7 turns per inch Z twist. The residual linear shrinkage of the yarn was 15.6%. The yarn was composed of a mixed shrinkage blend by weight of 35% of 4 /2 denier, 1 /2 inch staple acrylonitrile polymer fiber having a residual linear shrinkage of approximately 17%, 15% of 2 denier, 1 /2 inch staple aorylonitrile polymer fiber having a residual linear shrinkage of 3%, and 50% of 3 denier, 1% inch staple regenerated cellulose fiber. The yarn was spun from a stock blend of fibers on a modified cotton spinning system. A stabilized structure was knitted at a construction of 34 courses and 23 wales per inch in a configuration consisting of alternating courses of plain stitches and missed and tucked stitches. The fabric was then given a standard treatment of dyeing in a Beck at the boil, which treatment resulted in a shrinkage of 11% lengthwise and 25% widthwise. The resulting fabric was dried and stabilized open width on a pin tenter frame by stretching 14.8% in the width direction and overfeeding 16% in the length direction. The fabric was then napped and stabilized a second time by wetting out the fabric, then stretching 12% in the Width direction and overfeeding 8% in the length direction on a pin tenter frame. The resulting fabric resambled a light weight woven dress goods flannel and possessed the following properties:

Weight 9.8/60" yd. Percent stretch:

Wale direction 8.4

Course direction 12.5 Percent shrinkage:

Wale direction 3.8

Course direction 4.5

The stretch resistance, stiffness and body of the above fabric may be further improved by an optional final finishing step involving the application to the fabric of a commercially available polyacrylic acid ester coating composition.

EXAMPLE VI This example illustrates for purposes of comparison samples of commercially available standard woven and knitted fabrics which were used as controls in comparing the properties of these standard fabrics with the improved properties of the fabric prepared in accordance with this invention. The commercially available woven fabric was a flannel-type fabric made from yarns which were spun using a long staple cotton spinning system and having a count of approximately 15 singles cotton count. The yarn was composed by weight 35% of 4 /2 denier, 2-inch staple acrylonitrile polymer fiber having a residual linear shrinkage of approximately 17%, 35 of 3 denier, 2-inch acrylonitrile polymer fiber having a residual linear shrinkage of 03% and 30% of approximately' 64s grade wool. The finished fabric is constructed at 79 ends x 73 picks. The fabric was finished by a sequence of steps involving napping, shearing, fulling, dolly washing, Beck dyeing, drying, shearing, and semidecating. The fabric was an aesthetically attractive worsted type flannel with moderate cover.

The standard commercial plain jersey fabric was a typical fabric having a high differential stretch in two directions which is true of most knitted plain jersey fabrics. The yarn was composed of 80% by weight of mixed shrinkage acrylonitrile polymer staple fibers and 20% by weight wool, the mixed shrinkage acrylic portion being composed of approximately 40% of acrylic fiber having a residual linear shrinkage of approximately 17% and 40% of the same acrylic fiber having a residual linear shrinkage of 0 3%, the yarns being essentially identical to those used in Example IV. The knitted fabric was treated by dyeing in a Beck at the boil, drying and steam calendering.

The two commercial fabrics described above which were used as controls are characterized by the following The chief advantage of this invention is the provision of a novel knitted synthetic fabric which possesses most of the desirable physical properties and aesthetics which are characteristic of woven fabrics without the disadvantages normally present in knitted fabrics, as well as the discovery of a process for preparing said fabrics which is more economical than standard weaving operations. The novel fabrics produced in accordance with this invention have superior performance over their woven counterparts as well as over knitted fabrics prepared from the same fibers by hitherto known methods. The new products exhibit outstanding resistance to wrinkling and shrinking during washing as well as freedom from wrinkling during wearing, the wash and wear wrinkling performance being superior to that of woven fabrics of equivalent weight. The improved fabrics also possess satisfactory resistance to pilling and scuffing as well as satisfactory crease retention, resistance to bagging, and good dimensional stability. The novel synthetic fabrics also possess improved wearing properties over woven or knitted fabrics made from natural fibers. Also these new fabrics have good drape and body. The particular advantage of this invention lies in the fact that it provides for the first time a light weight knitted fabric (i.e., less than 12 \oz./ 60 inch yard) which has all of the physical properties and aesthetics of a woven fabric which makes possible the preparation of fabrics in a number of light weight apparel end uses. The novel fabrics also have 1 l more equal and greater stretch resistance and greater dimensional stability after laundering than plain knitted jersey fabrics.

The fabrics of this invention may be used in preparing products for a number of end uses, among these uses including mens sport shirts, suits and slacks, womens and childrens suits, skirts, shirts and outerwear, suitings, slacks, dresses, skirts, jackets, trousers, uniforms, overcoatings, shirtings, sport coats, fiannels, tweeds, coatings, blankets, upholstery, curtains and drapes, home furnishings, filters, felts, and other apparel and industrial fabrics.

It will be apparent that many widely different embodiments of this invention may be made without departing from the spirit and scope thereof, and therefore it is not intended to be limited except as indicated in the appended claims.

I claim:

1. The process of preparing a stretch resistant knitted fabric which comprises feeding a yarn into a single needle bed circular knitting machine to form a course of plain stitches, feeding a second yarn into the said machine behind the first yarn to form a knitted greige fabric having the second yarn forming a course in a laid-in configuration across the width of the fabric and being shorter than the first yarn and having a tightness factor as herein defined of at least 1200 shrinking the greige fabric and finishing the shrunken fabric including the steps of stretching the shrunken fabric Widthwise and overfeeding the said fabric lengthwise while heating said fabric to a temperature of at least 200 F. under such conditions that it has a stretch of less than about 15% in each direction, each of the feed yarns being composed of at least 50% by weight of synthetic organic linear polymeric filamentary material with a minimum residual linear shrinkage of at least 10%; and bonding the fibers to each other at isolated contiguous points only.

2. The process of claim 1 in which the filamentary material is in the form of staple fibers.

3. The process of claim 1 in which the synthetic portion of the yarn is a linear fiber-forming polyamide.

4. The process of claim 1 in which the synthetic portion of the yarn is a polyester.

5. The process of claim 1 in which the synthetic portion of the yarn is a polymer of acrylonitrile.

6. The process of claim 1 in which each of the two feed yarns have filamentary components having different amounts of residual shrinkage.

7. The process of claim 1 which includes knitting plain courses alternating in single succession with laid-in courses of missed and tucked stitches, each successive laid-in course having missed and tucked stitches in different wales from the arrangement in the preceding laid-in course, and the missed and tucked stitches in each laid-in course alternating in single succession.

8. The process of claim 1 in which each of the two feed yarns has a linear residual shrinkage of from about 15% to 30%.

References (Iited in the file of this patent UNITED STATES PATENTS 2,117,208 Page et a1 May 10, 1938 2,174,439 ickens Sept. 26, 1939 2,377,490 Getaz June 5, 1945 2,383,986 Page Sept. 4, 1945 2,541,500 Carney Feb. 13, 1951 2,591,861 Pannaci Apr. 8, 1952 2,705,880 Kinzinger et al Apr. 12, 1955 2,714,756 Redman Aug. 9, 1955 2,836,970 Deiss et a1. June 3, 1958 2,842,947 Lindner July 15, 1958 3,053,609 Miller Sept. 11, 1962

Claims

1. THE PROCESS OF PREPARING A STRETCH RESISTANT KNITTED FABRIC WHICH COMPRISES FEEDING A YARN INTO A SINGLE NEEDLE BED CIRCULAR KNITTING MACHINE TO FORM A COURSE OF PLAIN STITCHES, FEEDING A SECOND YARN INTO THE SAID MACHINE BEHIND THE FIRST YARN TO FORM A KNITTED GREIGE FABRIC HAVING THE SECOND YARN FORMING A COURSE IN A LAID-IN CONFIGURATION ACROSS THE WIDTH OF THE FABRIC AND BEING SHORTER THAN THE FIRST YARN AND HAVING A TIGHTNESS FACTOR AS HEREIN DEFINED OF AT LEAST 1200 SHRINKING THE GREIGE FABRIC AND FINISHING