US 3097127 A
Description (OCR text may contain errors)
y 1963 B. e. OSTMANN, JR 3,097,127
PROCESS FOR MECHANICAL WORKING OF NON-WOVEN WEB Filed Dec. 1, 1960 hoDooma mmzma M25032 mm z mQmDOh xOm Q mI mmxzz mmmml memml ATTORNEY United States Patent 3,097,127 PROCESS FOR MECHANICAL WORKING OF NON-WOVEN WEB Bernard G. Ostmann, Jr., Wilmington, DeL, assignor to E. I. du Pont de Nemours and Company, Wilmington,
DeL, a corporation of Delaware Filed Dec. 1, 1960, Ser. No. 72,970 7 Claims. (Cl. 162-446) This invention relates to a process for the production of anew and improved non-woven fabric. It is particularly directed to a process for providing a synthetic non-woven interliner fabric for use in the manufacture of Wearing apparel.
The function of the interliner material is to add body and to provide a springiness to the apparel in which it 1s used. The materials presently in use as interliners are generally considered to be deficient property-wise and too expensive to produce.
As wash-wear suiting interliner, a fabric having a composition of cellulose triacetate fiber and goat hair and a [fabric of Dacron (registered trademark for Du Ponts polyester fiber) taffeta are in predominate use. In washwear shirting interliners, the same taifeta and a resintreated cotton fabric are most popular. The primary requirements of these fabrics in such use are dimensional stability and wash-ability. Dacron taffeta fabric has these properties but is considered, by many, to be too expensive. The Dacron taffeta has some deficiencies in that it exhibits slipperiness, i.e., it is difficult to handle in cutting and sewing, raveling during cutting, sewing, washing and Wearing, failure to conform to the body contour of the wearer and a tendency to cause a hard, rough, puckered lapel edge. The cellulose triacetate fiber-goat hair fabric and the resin-treated cotton fabric are less expensive but exhibit the more serious deficiencies, in use as interliners, of wet extension and poor dimensional stability to washing. Resin-treated cotton fabrics are also inferior to Dacron taffeta fabric in crease recovery and shrinkage during ironing.
The so-called hair cloths are generally used as interliners in regular-wear, i.e., dry-cleanable suits, sportcoats and topcoats. These hair cloths are woven fabrics containing cotton or rayon, wool, animal hair--usually goat hair blended into the filling yarn only. This results in a unique combination of directional properties. As an example of the unique properties attained through the use of such fabric, a coat front has a stiff springy roll in the lapel, or in a horizontal direction, and a soft drape in the vertical direction.
These unique directional properties which hair cloths exhibit have hitherto been unattainable in synthetic-fiber paper. Even machine papers with directional stiffness properties do not exhibit the combined properties of spring-iness and roll contributed by the hair fibers. It has been noted, however, that goat hair does contribute to a great degree to the property of springiness in a fabric when it is made a component part of a fabric in the interliner category.
The two major requirements of an ideal interliner are fabric-like strength and fabric-like stiffness. This presents an obvious problem in non-woven fabric since an increase in strength will generally result in papery stiffness due to the very nature of the fabric. T he synthetic non-woven interliners of this invention have the combination of high stiffness, high tensile strength, high tear strength, high porosity and good fold without papery kinks, cracks or breaks. They also exhibit stitch tear strength resistance as well as edge stability, i.e., lack of fraying. They are superior to hair cloth interliners in dimensional stability, crease recovery, lack of fiber leak-age and resistance to ravel-ing. They are superior to Dacron taffeta inter- 3,097,127 Patented July 9, 1963 liners in that slipperiness, raveling and failure to conform to body contour, all problems presented by a Dacron taffeta fabric, have been substantially eliminated. The cost of producing the instant interliner is also below that of Dacron taffeta fabric.
It is, therefore, an object of this invention to provide a process for the formation of a non-woven interliner which is relatively inexpensive to produce and has the highly desired physical properties. It is a further object to provide a process for the production of an inexpensive non-woven synthetic interliner having the highly desired physical properties for use in wash-wear and regular-wear apparel. Additional objects and advantages will be apparent as the invent-ion is hereinafter described in detail.
The objects of this invention are accomplished by providing a process for producing non-woven interliner fabric which comprises the formation of a fiber/fibrid waterleaf having a composition of at least about 10% by weight fibrids,.drying the waterlea-f, subjecting said waterleaf to a temperature of at least about 200 C. to provide a fusionbonded fabric, subjecting the resultant bonded fabric to mechanical working and abrading in an atmosphere of steam, washing the fabric and drying.
T o be designated a fibrid, a particle must possess (a) an ability to form a waterleaf having a couched wet tenacity of at least about 0.002 gram per denier when a plurality of the said particles is deposited from a liquid suspension upon a screen, which waterleaf, when dried at a temperature below about 50 C., has a dry tenacity at least equal to its couched wet tenacity and (b) an ability, when a plurality of the said particles are deposited concomitantly with staple fibers from a liquid suspension upon a screen, to bond a substantial weight of the said fibers by physical entwinement of the said particles with the said fibers to give a composite waterleaf with a wet tenacity of at least about 0.002 gram per denier. In addition, fibrid particles 1 ave a Canadian freeness number between and 790 and a high absorptive capacity for water, retaining at least 2.0 grams of water per gram of particle under a compression load of about 39 grams per square centimeter. The fibrid is formed of a polymeric material synthesized by man as distinguished from a polymeric product of nature or derivative thereof.
Any normally solid wholly synthetic polymeric material may be employed in the production of fibrids. By normally solid it is meant that the material is non-fluid un der normal room conditions. By an ability to bond a substantial weight of (staple) fibers is meant that at least 50% by weight of staple based on total staple and fibrids can be bonded from a concomitantly deposited mixture of staple and fibrids.
It is believed that the fibrid characteristics recited above are a result of the combination of the morphology and non-rigid properties of the particle. The morphology is such that the particle is non-granular and has at least one dimension of minor magnitude relative to its largest dimension, i.e., the fibrid particle is fiber-like or film-like. Usually, in any mass of fibrids, the individual fibrid particles are not identical in shape and may include both fiber-like and film-like structures. The non-rigid characteristic of the fibrid, which renders it extremely supple in liquid suspension and which permits the physical entwinement described above, is presumably due to the pres ence of the minor dimension. Expressing this dimension in terms of denier, as determined in accordance with the fiber coarseness test described in Tappi 41, A-7A, No. 6 (June) 1958, fibrids have a denier no greater than about 15.
Complete dimensions and ranges of dimensions of such heterogeneous and odd-shaped structures are difficult to express. Even screening classifications are not always completely satisfactory to define limitations upon size since at times the individual particles become entangled with one another or wrap around the wire meshes of the screen and thereby fail to pass through the screen. Such behavior is encountered particularly in the case of fibrids made from soft (i.e., initial modulus below 0.9) polymers. Hard polymers (i.e., initial modulus above 0.9 g./ denier) are more readily tested. As a general rule however, fibrid particles, when classified according to the Clark Classifica tion Test (Tappi 33, 294-8, No. 6, [June] 1950) are retained to the extent of not over on a 10-mesh screen, and retained to the extent of at least 90% on a 200-mesh screen.
Fibrid particles are usually frazzled, have a high spe cific surface area and, as indicated, a high absorptive capacity for water.
Preferred fibrids are those the waterleaves of which when dried for a period of twelve hours at a temperature below the stick temperature of the polymer from which they are made (i.e., the minimum temperature at whicl a sample of the polymer leaves a wet molten trail as it is stroked with a moderate pressure across the smooth surface of a heated block) have a tenacity of at least about 0.005 gram per denier.
Fibrid particles are described and claimed in copending United States application Serial No. 788,371, filed January 22, 1959, now United States Patent 2,999,788, dated September 12, 1961.
The term staple fiber is meant to designate fibers or filaments of textile denier which are short in length as opposed to continuous filaments. In general the lengths of the fibers may vary from a fraction of an inch to several inches. For the present invention, however, it is preferred that the fibers be of from /s to about 1 inch in length although longer lengths of longer fibers may be substituted in part for the staple fibers herein employed.
The term waterleaf is meant to designate the material deposited on a foraminous surface in a conventional papermaking apparatus which results by providing a slurry of fibers and fibrids, thoroughly mixing the fibers and fibrids, causing the slurry to pass into a conventional single or multiple headbox and onto a moving screen where deposition occurs. The waterleaf may be composed of a single layer of thoroughly mixed component fiber/fibrid parts, yet may also consist of several layers where each layer has a particular descriptive composition. The process for preparing a waterleaf, as described herein, is disclosed in detail in copending United States application Serial No. 788,371.
This invention will 'be more readily understood by reference to FIGURE '1 which is a flow sheet designed to depict, generally, the formation of a fibrid waterleaf and the interliner fabric whichis the subject of this invention.
FIGURE 1 discloses the individual preparation of both fibrid and fiber slurries in aqueous dispersion. Each dispersion is led to a mixer where thorough intermixing is performed before the fiber/fibrid slurry is conducted through the headbox where deposition takes place and onto the moving screen of the Fourdrinier machine used in papermaking. The waterleaf then passes to a dryer and onto a heat-treating station where suflicient heat is supplied to bond the sheet by fusion. At this point, the waterleaf may be exposed to an embossing apparatus as a separate step or in conjunction with the aforementioned application of suificient heat to provide a fusionbonded fabric. From this point the fused-bonded sheet .or fabric is caused to undergo a fulling or compaction step in an atmosphere of steam where it is subjected to mechanical working and abrading action prior to final washing and drying. The drying should take place at a temperature of at least about 90 C.
It may be desirable to provide a colored fabric. Thus, dyeing may be accomplished'by padding a dispersed dye into the waterleaf prior to drying and development in the heat-treating step following the teachings of United States Patent 2,663,612. However, dyeing may also be accomplished while the fabric is being subjected to mechanical working in the fulling step of the process with equally satisfactory results.
After forming and drying the waterleaf as described earlier, the individual fibers and fibrids of the waterleaf are bonded together by fusion. This can be accomplished by applying pressure in conjunction with heat or by application of heat alone; however, if the process includes a pressure-free fusion bonding step, the use of forced hot air applied to the supported sheet is preferred. The fused sheet may then be heat embossed as desired or it may be left in the fused condition. If the sheet is to be embossed, this may be accomplished either after fusion-bonding or in a combined fusion-bonding embossing step using heat patterned rollers. In either case, there should be an application of sufiicient heat to produce the required fusion bonding of the sheet and this amounts to at least about 200 C. with regard to polyester fibers and fibrids.
The fusion-bonded fabric is then exposed to a fulling or compacting step which subjects the sheet to a mechanical working and abrading action in an atmosphere of steam. This consists of applying transient compressive stresses in the plane of the web coupled with induced short period, high amplitude flexing. This procedure is cyclically repeated a suific-ient number of times to result in the sheeting being folded back on itself transversely at least 15 times per inch and preferably 20 to folds per inch. The sheeting is also simultaneously subjected to mild, planar or tangential abrasion at least equivalent to that involved in moving the fabric over a smooth wood surface under a load of 0.5 pound per square inch. This fulling or compacting may readily be accomplished in a machine such as the Compactor offered by Fabric Research Laboratories, Inc., and Riggs and Lombard, Inc. This fulling or compacting may also be accomplished in a modified fulling mill; the modification being in the use of steam without water.
This invention will be further illustrated, but not limited, by the following examples.
EXAMPLE I In the preparation of a non-woven fabric, two components are employed. The first is Dacron polyester fiber staple material 1 /2 denier per filament inch long staple. The second component is a polyester fibrid. The fibrous components consist of 82% of the staple fiber and 18% of the fibrids. An aqueous suspension of the fibers is prepared with a consistency of 0.09%. A separate slurry of the copolyester fibrids is prepared at a consistency of 0.06%. This latter slurry includes 1 /2% by weight, based upon the dry fibrids, of a wetting agent consisting of a neutral condensation polymer of sodium naphthalene sulfonate and formaldehyde (Daxad-11 manufactured by Dewey and Almy Company). The use of this wetting agent in a process of this nature permits an excellent degree of uniform dispersion of the fibrid without foaming and without flotation of the fibrid.
The two slurries are combined in a mixing T in a manner similar to that described in copending application Serial No. 788,371, referred to earlier. The proportion of slurries is adjusted to provide a sheet having the above-indicated ratio of staple fibers and fibrids. Using this mixed slurry, a sheet product is prepared on a papermaking machine employing a triple headbox to give a three-layered structure in which the top and bottom layers consist essentially of 100% copolyester fibrids, and the middle layer consists of a mixture of fibrids and staple fibers. The quantity of fibrids on each of the two surfaces comprises between 1 and 2% of the total weight of the product.
After the waterleaf is deposited and formed on the wire, it is dried and fused in a gas-fired fuser in which the sheet is supported in a horizontal position on a supporting frame with a hot air temperature of 460 F., a speed of 10 yards per minute, an exposure time of 20 seconds with an overfeed rate of 5%. The resulting sheet has a basis weight of 2.6 ounces per square yard and a thickness of 21 mils. It has a tensile strength of 20.3 pounds per inch in the machine direction and 13.6 pounds per inch in the transverse direction. Elongation at the break is 24% in the machine direction and 33% in the transverse direction.
Following the fusion step, the sheet is treated in a conventional fulling mill, but in an atmosphere of steam, in a process which dyes, works and abrades the fabric. The following table shows the processing conditions.
Table I APPLICATION, FULLING AND FINISHING Ounces/50 Gallons Ounces/50 Gallons Fulling Agents:
Avitone '1 (Registered trademark for Du Pont Company, an anionic hydrocarbon sulfonate dispersing agent in the form of a semi-fluid pas 6. 3 Carolid (Sold by the Tanatex Corporation), a
solid modified phenol derived dispersed dyestuff carrier 63.0 Vertex (Sold by Swift and Company), sodium oleate 111.0 Nopco 1479A (Sold by Nopco Chemical Company), a liquid fatty alkylolamide condensate, iulling lubricant 50.
Equipment Fulling mill. Temperature 210 F. with steam. Speed 250 y.p.m. Smooth feed rolls. No extra weights on trap. Material in rope form. Yardage 600 yards (300 yards on eac5 side of mill). Time 25-minute heat-up period; ap-
proximately 1% hour runprepared which is suitable for use as a wash-wear shirt component. The fibrous elements employed in this example are Dacron polyester fiber staple, l /z denier per filament, A inch long, and a copolyester fibrid consisting of 80% poly(ethylene terephthalate) and 20% poly- (ethylene isophthalate). However, in the preparation of this interliner material, only a single layer non-woven structure is used. There is no surface layer on either side. Rather, the two slurries are blended directly to give a non-woven structure comprising 86% by weight of staple fibers and 14% by Weight of polyester fibrids. The material as deposited has a basis weight of 1.75 ounces per square yard (dry weight). As described in the pre ning time; IO-minute cooldown period. Passes through mi1l 100.
' About 0.15. 15 per inch. Washing:
Equipment Dolly washer. I Time 35 minutes for 100 yard pieces. Temperature 110 F. Drying:
Equipment Horizontal, layered pm frame. Temperature 250 F. Exposure time Approximately 6 minutes. Spee Approximately 20 y.p.m.
The finished sheet product after drying is a non-woven fabric with a tensile strength of 13 pounds per inch in the machine direction and 12 pounds per inch in the transverse direction, with an elongation of 23% in the machine direction and 24% in the transverse direction. The basis weight is 2.8 ounces per square yard and the thickness was 16 mils. It has a Mullen burst strength of 71 pounds per square inch, a tongue tear strength of 1.9 pounds, and excellent washability and dry-cleanability, no fiber leakage and exhibits no sticking during ironing. The finished fabric is found to be excellent for use as a washwear suiting interliner and was appraised as superior in appearance to an interliner containing cellulose triacetate fiber and goat hair blend or resin-treated cotton interliners. Ninety suits were made using this material as an interliner and no failures or other problems occured in the cutting, sewing or wearing of the coats.
EXAMPLE II An interliner fabric of non-woven polyester material is ceding example, the material is formed on a papermaking machine and is embossed at 210 C. with a pressure of pounds per square inch for one minute using a press and l6-mesh screens to provide an embossed surface with a fabric-like appearance. The resulting fabric is a strong, soft, non-woven structure with a surface like a Woven fabric. It has a drape stiffness of 6 centimeters, a thickness of 12 mils and a soft but crisp handle.
EXAMPLE III An interliner fabric is prepared which is considered to be suitable for use in mens regular-wear suits. The fabric of this example is prepared in a manner similar to that described in the preceding two examples with the following two exceptions: the copolyester fibrid content of the Waterleaf is reduced to 10%. The polyester staple fiber is a spontaneously elongatable polyester staple 3 denier per filament Ai-inch long material. The preparation and use of spontaneously elongatable fibers is described in copending United States application Serial No. 27,476, filed May 9, 1960. The polyester staple fiber content of the waterleaf is 65% and the remainder of the material is 25% by Weight of goat hair. The non-woven as deposited ou the screen has a dry basis weight of 3.0 ounces per square yard. As in Example I, surface layers are used to prevent fiber leakage, particularly of the goat hair component. A surface layer comprising 0.5 ounce per square yard of a combination of 86% of the polyester fibers and 14% of the fibrids is deposited on each surface of the fabric during formation. During the embossing step, which employs restraining screens, the spontaneously elongatable fibers are elongated to provide a crimped polyester fiber component which enhances the softness and drapability of the non-Woven fabric. The goat hair pro vides springiness to a degree satisfactory for use in lapel and suit front interliners for regular-wear suits. The final interliner product has a basis Weight of 3.0 ounces per square yard, an elongation of 61% at the break, a tensile strength of 11 pounds per inch and a thickness of 30 mils.
EXAMPLE IV Following the procedure of Example I, a non-woven fabric of Dacron polyester fiber staple material and copolyester fibrids is prepared. The preparation of the waterleaf follows exactly the procedure described in Example 1.
During the preparation of the Waterleaf on the Fourdrinier machine, a dispersed dye mixture is padded onto the Web. The composition of the dye is the same as that shown in Table I, the medium gray shade. The application of this dyestuff is based on the technology described in United States Patent 2,663,612. By applying the dyestuif to the waterleaf in this stage, it is possible to obtain a fabric ready to undergo the later step of heat treatment in such a manner that the heat treatment will provide the necessary thermally-induced dye penetration taught in United States Patent 2,663,612.
As the non-woven web comes off the papermaking machine, it is dried and then heat-fused in the manner described in Example 1. Dye fixation and penetration presented no problems. The fabric obtained has a basis weight of 2.6 ounces per square yard and a thickness of 7 21 mils. It has a tensile strength of 20 pounds per inch in the machine direction and 13.2 pounds per inch in the transverse direction.
The heat-treated non-woven fabric is then subjected to a combined mechanical working and abrading step in an atmosphere of steam employing textile-processing equipment known as a compactor. The speed of the top roll of the compactor is 14 r.p.m. and the speed of the bottom roll is 9 rpm. Two passes through the machine are used for the entire length of the fabric. Steam at a line pressure of 60 p.s.i. is applied to the fabric in the nip of the compactor. The over-all speed of the fabric through the machine is approximately 15 feet per minute (speeds as high as 200 feet per minute can be employed). The take-01f rolls of the compactor are employed to maintain tension as the fabric leaves the nip rolls to avoid over-all shrinkage of the fabric.
The differential roll speeds of the compactor combined with the design of the nip-roll feed plate, operate to cause the fabric to be doubled back transversely on itself sharply at a frequency of approximately '20 folds per inch. At the same time the differential surface speed of the two rolls gives a mild abrading action on the surface of the fabric resulting in a surface containing a large number of firmly anchored protruding fiber elements, giving a soft, fabric-like handle and obviating any tendency of the fabric to stick during later processing, since the surface consisted 8 EXAMPLE -v An interl-ining fabric of non-woven polyester material is prepared which is suitable for use as a regular-wear shirt component. The fibrous elements employed in this example include those employed in Example II with the addition of a rayon fiber component. Copolyester fibrid content is Polyester fiber content is with 30% being rayon staple fiber. The waterleaf has surface layers composed of copoiyester fibrid and dacron fiber (50%) to minimize leakage of rayon fibers during washing. The material, deposited, has :a basis weight of 2.5 ounces per square yard (dry weight). .As described in Example II, the material is formed on a papermaking machine and is embossed at 210 C. with a pressure of 80 pounds per square inch for one minute using a platen press and 16 rnesh screens to provide an embossed surface with a fabric-like appearance. The resulting fabric is a soft, strong non-woven structure with a surface like a woven fabric. It has a drape stiffness of 6 centimeters, a thickness of 16 mils, and a soft but crisp handle. Because of the presence of rayon, the material is stanchable; without rayon, there is poor adhesion of the starch to a non-Woven fabric composed entirely of polyesters and copolyester fibrids.
Table II presents a brief and general summary of some of the interlincr compositions of this invention.
Table II INTERLINER COMPOSITIONS Fiber Component Fabric Use (percent) Fibrid Component (percent) Fabric Properties Surface Properties Weight Thickness (on/yd?) Tensile Strength (mils) (lbJillch) 1. Wash-wear suiting 75-85 Dacron 1 staple interliner.
1% denier per filament 4 long.
75-85 fDacron staple 1% denier per filament $4 long (or fibers may be single layer, a blend of at least 50% Dacron and up to 50% rayon st ple).
15-30 goat hair S.E. "Dacron 58-76 polyester staple 3 d.p.f., long.
side). 2. Wash-Wear shirt in- 15-25 polyester tcrhner.
3. Regular wear suiting inter or.
surface. 4. Regular wear shirt 15-64 rayon 3 d.p.f., interliner.
staple 15-64 Dacron 1% d.p.f., staple.
15-25 polyester (80% ZGT 20% 2G1 1% t0 3% fibrid surface on each 8-12 polyester fibrids 3 layers, with a blend of 86/14 Dacron staple] polyester fibrids on each 15-40 polyester fibrlds 3 layers, each surface layer being 0.1 to 0.8 oz./ yd. Dacron" staple] polyester fibrids at 15-50 2.3-2. 7 15-20 10+ (Machine directlon), 5+ (Transverse) Soft surface fabric bonded by fusion at 210 0. or bonded and embossed.
Soft fabric-like weave surface by roller embossing at 210 C.
2. 8-3. 2 25-30 See Item 2.
2. 0-3. 0 8+ See Item 2.
1 Du Ponts registered trademark for its polyester fiber. 2 Poly(ethylene terephthalate). 3 Poly(ethylene isophthalate).
predominantly of high-melting fiber components rather than the low-melting fibrid components.
Two passes through the compactor are employed to ensure that both surfaces of the fabric are treated equally. The over-all compactor treatment results in a total working of the fabric equivalent to approximately 40 folds per inch transverse to the machine direction of the material.
Following the compactor treatment, the dyed fabric may be washed and dried to give final interliner material of a medium gray shade. The tabric shows excellent washabil ity and retention of physical properties after dry cleaning. No evidence is observed of sticking of the intor-liner duping ironing. As in Example I, the interli-ncr is .used in making suits. No fabrication problems occurred in cutting, sewing, wearing or cleaning of the coats. It is considered that the results obtained with the compactor were equivalent with those obtained inthe fulling mill. As indicated, the processing actions of the two pieces of apparatus are found to be substantially the same.
The products of this invention may be used as interliners for wearing apparel, such as regular-wear and washwear suiting, shirting, over-coats, rtopcoat-s and jackets. Other end uses include its incorporation into specific garment components, such as pocketing, findings and waisthands. It may also be used in bagging, tarpaulins, rtent materials and in protective coating materials, as well as in food packing materials and in other similar packing materials. It also has effective use in draperies, upholstery backing, disposable garments, tea bags and materials of that nature.
The fusion step in the instant process eliminates fiber leakage and improves tensile strength in the synthetic nonwoven sheeting. lFiber leakage from the surface of the interliner through the shell fabric creates a lint-covered appearance while a lack of tensile strength would result in fabric failure when the mechanical stresses developed by dry cleaning and Washing are encountered. Calendering of the synthetic sheeting, as opposed to fusion, results in a sheet which is too stiff-and which produces a paper- 9 like noise When flexed. Fusion bonding produces a soft texture sheeting which does not exhibit paper-like noise.
The fulling or compacting step improves the balance of tensile strength and stiffness to a desired degree. Prior to step, the fusion-bonded fabric is too stiif and does not have the desired soft texture. It is believed that during this step the inflexible bonds in the synthetic fabric, which are present and contribute greatly Il'IO fabric stiffness, are broken while the flexible bonds remain unbroken, thus resulting in a fabric having the desired tensile strength yet a product which does not exhibit a degree of stiffness which would be detrimental insofar as its intended use is concerned.
By the process of this invention, a novel non-woven synthetic fiber/fibrid interliner is produced which overcomes the physical disabilities exhibited by the interliner fabric presently known to the art and which can readily meet the low cost requirements which are of paramount importance to the industry.
Many equivalent modifications will be apparent to those skilled in the art from a reading of the above without a departure from the inventive concept.
What is claimed is:
1. In a process for producing a synthetic non-woven interlinear fabric comprising the formation of a fiber/ fibrid waterleaf having a fibrid composition of at least about 10% by Weight, drying said Waterleaf and thereafter, subjecting said waterleaf to a temperature of at least about 200 C. to provide a fusion-bonded fabric, the improvement comprising subjecting the bonded fabric to mechanical working and abrading in an atmosphere of steam, said mechanical working and abrading comprising the folding of the said bonded fabric back on itself transversely at least about times per inch while simultaneously subjecting the said bonded fabric to mild tangential abrasion, subsequently washing the said bonded fabric and thereafter drying the said bonded fabric.
2. The product of claim 1.
3. In a process for producing non-woven synthetic inter-liner fabric comprising the formation of a fiber/fibrid waterleaf having a composition of about 86% poly (ethylene terephthalate) staple fibers by weight and about 14% by weight copolyester fibrid composition which consists of about by weight poly(ethylene isophthalate) and about 80% by weight poly(ethylene terephthalate), drying the said waterleaf and thereafter subjecting the said waterleaf to a temperature of at least about 210 C. to provide a fusion-bonded fabric, the improvement comprising subjecting the resultant bonded fabric to mechanical Working and abrading in an atmosphere of steam, said 10 mechanical working and abrading comprising the folding of the said bonded fabric back on itself transversely at least about 15 times per inch while simultaneously subjecting the said bonded fabric to mild tangential abrasion, subsequently washing the said bonded fabric and there after drying the said bonded fabric.
4. The process of claim 3 wherein the total fiber composition of the said waterleaf consists of about 82% by weight poly(ethylene terephthalate) staple fibers and the total fibrid composition of the said waterleaf consists of about 18% by weight copolyester fibrids.
5. The process of claim 3 wherein the total fiber composition of the said watenleaf is 90% by weight and consists of by weight spontaneously elongatable polyester staple fiber and 25% by weight goat hair, and wherein the total fibrid composition of the said waterleaf is 10% by weight and consists of copolyester fibri'ds.
6. The process of claim 3 wherein the total fiber composition of the said waterleaf is by weight and consists of 40% by weight polyester staple fiber and 30% by weight rayon staple fiber and wherein the total fibrid composition of the said waterleaf is 30% by weight copolyester fibrids.
7. In a process for producing a synthetic non-woven interliner fabric comprising the formation of a fiber/fibrid waterleaf having a fibrid composition of at least about 10% by weight, drying said watenleaf and thereafter subjecting said Waterleaf to a temperature of at least about 200 C. to provide a fusion-bonded fabric and embossing the said bonded fabric under sufficient heat and pressure to provide an embossed design thereon, the improvement comprising subjecting the fusion-bonded embossed fabric to mechanical working and abrading in an atmosphere of steam, said mechanical working and abrading comprising the folding of the said embossed fabric back on itself transversely at least about 15 times per inch while simultaneously subjecting the said embossed fabric to mild tangential abrasion, subsequently washing the said embossed fabric and thereafter drying the said embossed fabric.
References Cited in the file of this patent UNITED STATES PATENTS Wrigley et a1. Nov. 25, 1941 Bidgood Feb. 21, 1961 OTHER REFERENCES