SYNTHETIC FIBER The chemists who developed the unsupported film and made it possible to develop plastic curtains has created competition difficult to meet in low-priced curtains. The effect of plastic curtains on cotton marquisettes has been felt severely. Here again is a field that needs some “spicing up.” If our mills will continue to weave a fabric for the manufacture of curtains, but adopt a chemical product in the form of our new synthetics to compete with that other chemical product, the vinyl chloride film, we have a happy future. The films are competition in the low-priced field, but the functional and aesthetic qualities of marquisettes made from nylon, Orlon, Dacron, and perhaps other continuous filament synthetics yet to come, are such as to ensure their use and, in this author’s opinion, enthusiastic acceptance by the housewife. The age-old textile industry must move forward under the stimulus of that relative newcomer, the chemical industry. There are those who look upon long wear and serviceability with apprehension. The unenlightened sometimes say, “But if these things wear forever, what happens to our business?” Others are wedded
to their raw material and associate thems tally with the natural products they have used for generations. Neither of these points of view stand up in the cold light of analysis. As far as raw materials are concerned, the position of this company, and the position of any enlightened company, is that our job is to manufacture and distribute the best product we can. Whether the raw materials come from a plantation, from an animal, or from a chemical factory does not and should not influence us. Our interest is in the end and not in the means. Furthermore, as far as losing one’s business is concerned, there ia, I think, only one answer. It is a somber one, perhaps, but a realistic one: It is better to put yourself out of business than to have your competitor do it. The future of synthetics is assured. Someone will make the new fabrics. Healthy, progressive firms have nothing to fear from progress and they never have. It is better to be in the van than in the rear when movement is afoot. Today, a whole industry is marching forward. RECEIVED for review March 31, 1952.
ACCEPTED July 7, 1952.
Pile Fabrics JOHN P. MALIK The George W , Borg Corp., Delavan, Wis.
denier sizes, a fabric was T h e discussion deals with the adaptation of some of the produced which had good wide reception in many newer synthetic fibers in producing pile fabrics on a modipaint-holding capacity, good fields, such as clothing, tied circular knitting machine. The application of these resilience, and which applied home usage, and industrial fibers in various fields, such as industrial, apparel, and the paint very uniformly. Its applications. With the adhome usage, is discussed. Work dealing with the deresistance toward the solvent of the newer synthetic velopment of synthetic furs and their applications is outvents found in the ordinary fibers the field has been lined as is a typical development for the armed forces, oil and water paints was satisbroadened, in most cases rewhere synthetic fibers played a major part. The object sulting in improvements both factory. The dynel paint was to produce a fabric that was functionally satisfacroller has proved superior t o economical and functional. tory to replace wolverine or wolf, which was critically New fields of application one made of wool or mohair in short supply. have been explored with the pile, or natural shearling, newer synthetics and found especially because of its nont o offer good commercial matting properties when used Dossibilities. in water-based Daints. This discussion will concern itself with the adaptation of the In the garment and footwear industries, the new synthetic newer synthetic fibers in the field of knitted pile fabrics. The fibers have found wide acceptance as liner and trim materials. specific knitted-type pile fabric discussed is that in which a roving In the case of jacket liners, nylon has been used most successfully, offering the advantage of light weight t o produce good thermal is fed directly into a circular knitting machine. The resulting circular fabric is one in which the roving forms the pile directly, insulation properties. Other factors in its favor are its rapid the pile being held by a knit yarn. Fabrics having a pile height drying ability, moth resistance, launderability, dry cleanability, of up to 4 inches have been produced commercially. The denabrasion resistance, ability t o maintain pile height under normal sity is controlled by the rate of roving fed into the machine. wear conditions, good appearance, and its dyeability. Most of Fabrics ranging in pile density from 8 ounces t o 8 pounds per these factors also influence its use in slippers and stadium boots. square yard have been manufactured. The high temperature resistance of nylon has been a factor in its With the introduction of the paint roller, much of the drudgery approval whenever the fabric is combined with rubber. It stands of home decorating has been eliminated. Overnight, the houseup well under the vulcanizing process t o which such rubber items wife has become an expert painter. The shortage and high cost are subjected. All nylon stadium boots have become a commerof good natural bristle had its influence on the acceptability of the cially accepted item. The nylon outer shell and nylon liner have paint roller. The desirable properties in a paint roller are, and replaced leather and shearling, respectively, producing a more theae are a function of the fiber, the ability to hold a maximum styled and versatile boot at approximately one half the weight. amount of paint and to spread uniformly on the surface to be During the last 5 years, much work has been expended in the painted with a minimum amount of spattering, good durdevelopment of synthetic furs. The field is a tremendous one and ability, and ease of cleaning. After testing the various newer offers unlimited opportunities. The initial goal was set a t making synthetics, it was found that dynel produced a fabric having a fabric that could be substituted for mouton. Working with the excellent consumer approval. By blending fibers of various naturally available fibers, such as wool and alpaca, definite prog-
ILE fabrics have found
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ress was made. Soon their limitations were realized and the possibilities of the newer synthetics, such as nylon, dynel, Vicara, Acrilan, Orlon, and Dacron were investigated. It was at once seen that the potentials were almost unlimited. Considerable difficulties-carding, dyeing, knitting, shearing, and finishingarose in the processing of the newer synthetics. Through tedious experimentation and with the assistance of the fiber manufacturers, these difficulties were soon eliminated. Synthetic furs have been made using dynel, Vicara, Acrilan, and Orlon, individually and in blends. By selection of proper denier size, fabrics can be produced to give almost any degree of softness, thus simulating the natural furs. The nonwater absorption properties of the newer synthetics result in fabrics that dry rapidly and return to their natural fluffy state after drying. Through dyeing, almost any color can be obtained, giving good fastness properties superior to those on natural dyed furs. I n the case of persons being allergic to natural fibers, synthetics will offer relief. Blends of Vicara and dynel have found wide acceptance when made into mouton-type fabrics. These are being used by manufacturers as collar material on storm coats and children’s snowsuits. The fabric stands u p well in dry cleaning and home Iaundering, and in the case of the snowsuit which must stand repeated washings, it is ideally suited. Because of its fast drying properties and thermal resistance, a mother can wash them in a home washer and dry them in a dryer-all of this in a little over an hour. This will, in most cases, eliminate the necessity of a child’s having to have two snowsuits. Garments made using 100% of the newer synthetics have been on the market for the last 2 years. Orlon and Acrilan lend themselves favorably to producing fabrics having furlike characteristics. Women’s coats have been made, esperimentally, from Acrilan fabrics. These have the fiber softness and drape commonly attributed to natural furs. With further work and improvements in the newer synthetics, it is entirely within the realm of possibility that synthetics of the more costly furs will be soon atbiined. I n 1949 The George W. Borg Corp. was aaarded a development contract by the Clothing Branch, Aero Medical Laboratory, USAF, to investigate the feasibility of making a simulated wolverine-type fabric. This material was intended as a replacement for natural wolverine or wolf on cold-weather parka garments. The Air Force saw the advantage of obtaining a functional fabric using this company’s method of approach. It was requested that they explore the available field of natural and synthetic fibers suitable in their estimation to produce a functionally satisfactory material. The outer garments, or parkas, of cold-weather clothing are provided with attached hoods which are bordered with furs. The fur is so attached that it breaks the force of high wind and a t the same time acts as a heat exchange chamber, the exhaled air warming the incoming air. Because of the high moisture content of the exhaled air coming in contact with the cold incoming air, moisture is deposited on the fur, forming frost. I n order that the man’s vision is not impaired or his face chafed by ice, it is imperative that the frost and ice be removed easily by periodic brushing. Through experience it has been found that wolverine fur is the most functionally suitable for ruff purposes. The availability of wolverine is very limited, being reported that not over 500 pelts per year are processed. The next best fur is a Siberian timber wolf, the availability being rather questionable. Experimentation was started to make a fabric having the functional characteristics and the general appearance of wolverine. The fabric would necessarily have a uniform underhair of approximately 1 inch supporting a guard hair averaging between 2l/2 inches and 3 inches long. The guard hair diameter to approximate wolverine should be in the neighborhood of 4 mils. It should be so placed that it stands perpendicular to the base and dense enough to give a good windbreak. Too dense a material or one in which the guard hairs do not have sufficient support re2148
sults in ice forming and freezing a number of them together. The guard hair must be firmly anchored into the material and have sufficient strength so that it does not pull out or break during the brushing ice-removal process. It must not be adversely affected by low temperatures. Moisture should not cause matting. The guard hair should maintain good resiliency and stiffness during the life of the garment. The frost- and ice-removal properties are a function of the stiffness; this is evidently iyhy wolverine has proved to be the most satisfactory of the natural furs. During early experimentation, natural fibers such as horsetail and cowtail hairs were tried; this proved to be a practical method of approach. Ruffs of these were made and tested in a cold chamber for frosting and ease of frost removal. Promising results were obtained. From the limited number of tests made, it was gathered that a functionally suitable material could be manufactured. Because of the unpredictable nature of the supply situation and the nonuniformity of the fibers, it was decided to concentrate efforts on evaluating commercially available monofilaments. Work was limited to nylon, saran, polyethylene, vinyl chloride, and Caden and fabrics were knit using these monofilaments as guard hairs, It was found that a heat-set nylon monofilament showed the most promise. The guard hairs mere positioned almost perpendicular t o the base. A range of fabrim were made using the heat-set nylon monofilaments in diameters of from 2 l / 2 to 8 mils. It was found that a 4- to 5-mil nylon filamenl produced a ruff material that had functionally the same ice-removal properties as natural wolverine. For underhair purposes it was found that 6-denier nylon staple gave the best support t o the guard hair. Thus, fabric has been thoroughly tested by the USAF under arctic conditions and found to be functionally satisfactory as a replacement for natural wolverine and wolf. Large procurementa of this material have been made a t a cost approximately one fourth that of the natural fur. Further work is being done in conjunction with the Air Force to investigate some of the newer fibers available in monofilament form. These will be tested t o determine their acceptance for this particular purpose. A knitted synthetic mouton-type fabric has undergone extensive testing by the WSAF. This material is intended for usage as collar and parka liner in cold-weather clothing. Acceptance has been given to three different types-blends of Vicara with dynel, Orlon, and Acrilan. For properly selecting the synthetic fibers and processing them with this unique process, synthetic fur fabrics which stand upon their own merits, competing with the natural furs only on a cost basis, have been made commercially. Working in conjunction with the Office of Quartermaster, General, Research and Development Section, interest in new applications of pile fabrics has been developed. About a year ago a new casualty evacuation bag was developed by the Quartermaster Corps. To overcome the lack of compressional resistance afforded by down, it was suggested that a dense pile fabric be positioned at points of maximum compression. For this purpose a ll/r-inch dynel fabric weighing 32 ounces per square yard and incorporating the good resilience of high denier dynel was developed. These bags were tested and given a high clo value of insulation. Specifications were written for this bag and procurements have been made. The armed forces are using an arctic mitt, the back of which has a piece of alpaca designed to be used as a nose wiper or face warmer. Tests show that a Vicara-dyne1 blend synthetic mouton fabric performs equally as well in regard to the removal of frost and ice. A heat-set nylon sock is now being evaluated as a replacement for the felt boot inserts. Tests show it to be equally as warm but having one half the weight. The ease of washing and rapid drying are a derided point in its favor. -4dynel liner material is now being evaluated as an insulator in
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SYNTHETIC FIBER cold-weather clothing. A lightweight shell fabric is quilted over the face of the pile fabric. Initial laboratory tests show it to be equally as warm as any lining material yet produced and approximately 25% lighter than the conventional types now being used. Fiber orientation is extremely important in providing the necessary properties of an efficient garment insulator. When the fibers are directed parallel to compressor force, such as in a pile fabric, the fabric resists deformation to a greater extent than similar weight insulation fillers prepared from carded webs. When the effects of compressive forces are minimized, significant improvements result because of greater thickness, since greater thickness means greater insulation, but the maintenance of thickness is even more important than is commonly realized because of the loss of heating energy that occurs aa the result of bellows-type action. It will be obvious that any material which readily re sponds to thickness changes under moderate loads will produce considerable heat transfer by evolving occluded warm air which is replaced in turn by cold air.
their ability t o withstand compressive for decreases in thickness under moderate load, minimize this tendency for bellows-type action. Conventionally, woven pile is characterized by its extremely high density and particularly by its high total weight per pile ratio. This unique knitted type permits considerable advantage in providing greater pile density per total weight. The versatility of the process permits the inclusion of varying length fibers and fibers that would be difficult to process by other techniques. For example, a feather fiberdyne1 blend pile fabric waa recently made on this company’s type of equipment. It has been attempted to show how and where some of the newer synthetic fibers can be used in pile fabrics. Given a fuller denier range, their application will be further extended, Incorporating into the fibers better crimp, good resilience, and rapid recovery will make them more versatile.
Knit Goods F. F. HUBACH Princeton K n i t t i n g Mills, Inc., New York, N . Y .
HE subject of knit goods
he hydrophobic fibers provide new horizons for both cirAnnual fabric production will be approached along cular- and flat-knitted fabrics, for a variety of end uses, inreached a high of around 110,historical lines starting cluding apparel fabrics and also household and industrial 000,000 square yards and, with the positions the manfabrids. Filament and spun yarns, especially in blends, because of conditions which made fibers assumed upon will be employed as individual yarns and in combinations will be mentioned later, fell Grst being available to the to achieve fabrics with predetermined characteristics. to about 65,000,000 square knitters, their influence upon yards in 1951, with further the conventional knitting reductions in sight. At least equipment then in place, and 9Sy0 of current productions the consumer reaction to the are used in the lower priced oroducts which ameared in small tieccs. the market. More space will be given to the circular and warp The second field of knitted yarn acceptance was in men’s knitting industries but the hosiery industry will be covered as well. half-hose, and to a lesser degree in ladies’ seamless hose. Here The chicf raw materials available to the knitting industries, again, equipment changes were made, permitting lighter weight prior to the man-made fibers, were cotton, wool, blends thereof, hose, and more important, fancy styles for men’s wear. When and silk. Although sizable quantities of cotton and wool are acetate appeared, it immediately contributed to the fancy styles still being consumed and will continue to be, this paper shall be because of its cross-dyeing characteristics. confined to a discussion of the man-made fibers, starting with Originally, the circular-knitted underwear productions were viscose process rayon, cupra-ammonium, and acetate and consupplied by the vertical operation, wherein fabric was knit and tinuing into the hydrophobic group, starting with nylon. garments were cut, and the cutter establishment, which purchased The knitting industries quickly accepted continuous filament finished fabrics from the independent knitter. I n the mid 1 9 3 0 ’ ~ ~ viscose process rayon when it appeared and became the major certain rayon producers installed knitting equipment and entered consumer of the product for a number of years. An early obserthe finished fabric market, selling to cutters. Within a few years vation led to the conclusion that refinements were necessary in the competitive factors in the sale fabrics became severe; this all types of knitting machines, especially the need of finer gage caused certain independent knitters to turn to circular-knitted machines. The manufacturers of all types of knitting equipment outerwear fabrics during the late 1930’s. quickly responded and so aided materially in the progress made. Circular-knitted outerwear fabrics, chiefly of viscose rayon, The first volume production in knitted rayon was the circularachieved a fair volume, but their productions are limited beknitted underwear fabric used in women’s and misses’ small cause the fabrics lack certain features which the public demands. piece underwear and in a smaller way in slips and nightwear. The circular knitting industry is in position to use sizable quantiThe consumer quickly accepted these new, reasonably priced ties of cellulose yarns if these can be engineered to provide the garments, which were more appealing and lighter in weight than fabric characters needed to obtain consumer acceptance. the previous knitted garments available in volume. Productions The warp-knitting segment of the industry consumed relatively grew as more raw material became available, with the growth small poundages of viscose as it became available and did not being almost entirely in small pieces, with which the consumer become an important man-made fiber consumer until acetate acceptance was unquestioned. Acceptance of knitted nightwear yarn appeared. Because of the broad weaving-yarn demands, the was fair, with less success in slips, because of poor fabric stability. warp knitters were usually short of yarn; this condition has now
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