Acetate ASHTON M. TENNEY 4. M. Tenney Associates, Inc., 260 Madison Aue., New York,N . Y . by better and more useful Trends i n per capita consumption of textile fibers for fibers a t a much cheaper nonindustrial use i n the United States, showing the mission’s trade practice price. (Nylon consumption relative favorable position of acetate fibers, are given for rules effective February probably now exceeds the the past 20 years. A discussion of the economic relation 9, 1952, have established highest point ever reached of the natural and man-made fibers, as shown by textile the following definitionby silk, via., 80,000,000 fiber prices in the United States, suggests a current adAcetate: man-made textile pounds.) Rayon and acevantage for acetate filament yarn, and a present and probfibers and filaments comtate filament yarns were deable future advantageous price for acetate staple fiber. posed of cellulose acetate, liberately created tt8 a subA study is made of the diversified use of the different fibers and yarn, thread, or textile stitute for yarns made from in fabrics and the widening acceptance of acetate because fabric made of such fibers natural silk. From the time of its special characteristics. Such properties as resiliand filaments. these man-made yarns were ence, plasticity, and dryness of acetate and the new manH i s t o r i c a11y, cellulose launched, it was recognized made fibers are discussed, and the relative importance of acetate was the first organic that these new products these characteristics in fabrics of each kind of fiber is chemical compound to be would replace in appearance enumerated. Some recent developments in dyeing and created for textile fiber and and at a much lower price finishing processes for fabrics containing acetate yarn plastic film purposes. I t s the silk yarns employed in and/or staple are mentioned, together with the probable characteristic fiber appearheavy and medium weight increased demand for acetate fibers through their emance, beautiful luster, satins, taffetas, and crepes. ployment. sparkle and bloom, softness The lower relative strength to touch, and drapability of the acetate and rayon fiare quite different from ber was not a deterrent in rayon, a fiber of pure regentheir use as a replacement erated cellulose. Both aceyarn for these historically tate and ravonareconsumed silk fabrics, as the absolute strength in large quantities, and separately and together must face the com-DoDular * - of the acetate and rayon in the fabric weight required for the replacement construcpetition of each other and the new man-made fibers as they appear. tions was more than adequate for safe garment wearability. It What effect the introduction and use of the new fibers will have was soon recognized that the previous use of silk in these cloth conon the current economic position of acetate in wearing materials structions wasacostlywaste of strong finefiber, whichnowwould be or decorative fabrics is purely speculative and the validity of my utilized in sheer fabrics where strength and fineness were essential. opinion, while based on the interpretation of statistics and my own For example, in 1929 silk consumption in the United States experience in the marketing of textiles, should be accepted or rereached its highest point of 80,000,000 pounds of which only jected on each individual’s personal predilection. 60,000,000 pounds were being used in fine woven silk goods, and I n musing on the ultimate fate of a fiber, I like t o believe that 20,000,000 for women’s hosiery. While both rayon and acetate none are t o be left by the roadside. It has been stated that in the fiber could be made into hosiery of equal or better uniformity and decade 1929 t o 1939, the increase in the consumption of acetate appearance than silk, neither of these fibers could compete in this and rayon simply represented a larger woven fabric total and was field with silk because of the lack of the necessary strength and not accomplished at the expense of either cotton or wool. Howelasticity in such lightweight constructions. Nylon with fine ever, in those ten years the consumption of silk in the United filaments, strong and more elastic than silk, was yet to be created. States practically disappeared. Silk fiber has many basic desirable properties which in rayon, I have immense respect for the individual integrity and excelacetate, and new fiber creations have been augmented or reprolent qualities of silk, wool, and cotton created by nature for other duced at tremendous reductions in cost to the consumer. I t purposes but later adapted by man foi his own special textile use, could be said that in the main all man-made filaments are silklike. and now that man has learned t o create through chemistry new Basically, this is due t o the fact that they are all designed to imitextile fibers having predetermined desirable properties not existtate and improve the uniformity and evenness of the continuous ing in the world before, I am tempted to paraphrase a quotation lustrous filament &st found in real silk. Man-made filaments in part from a great Buddhist’s daily prayer for the world, “Let all have in part met the historic pent-up demand of women for (natural fibers and the new ones as created) without enemies, luxurious personal decoration by providing a substitute for silk without obstacles, overcoming sorrow, and attaining cheerfulness, a t a continual lowering of price; this has not yet satisfied their move freely each in his own path.” insatiable appetite in spite of the expansion of silklike products Of over 100 vegetable and animal fibers which were and are still available for man’s adaption for clothing his body and decorating from a production of 200,000,000 pounds yearly 20 years ago to about three quarters of a billion pounds yearly today. Acetate his home, he selected centuries ago in the main only threenamely, silk, wool, and cotton-which have reached and, with filament yarn has in the last 20 years shared with rayon, and more the exception of silk, maintained an increasing volume consumprecently nylon, an increasing relatively larger part of this outertion. wear dress goods and underwear business. It is apparent that these great natural fibers including silk in As has been noted, rayon production passed the greatest use of silk in this country in 1929. Twenty years later in 1949 acetate lesser amounts (now about 8,000,000 pounds a year) are and will passed the greatest use of rayon in the same textile category. I n continue in the consumers’ favor as long as they are not replaced
HE Federal Trade Com-
T
September 1952
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the last ten years while acetate filament protluc tion has increased almost one and a half times annually, rayon production for t.extile appar,el use has grown less than one third of its former annual production rate. I n 1950 acetate filament production was 327,000,000 pounds a t an average denier of 108 and textile rayon filament production was 319,000,000 pounds a t an average denier of 129. In the war years rayon producers made rapid conversions of their manufacturing facilities for textile apparel yarns to high t,eiiacity tire yarns, and then increased capacity in this new field, until in 1950 high tenacity filament yarn production reached a total of 308,000,000 pounds a t an average coarse denier yarn of 1554. The price of 1650 denier was 61 cents. For a number of years the fine denier apparel acetate yarns, with fineness more nearly corresponding t o that formerly used in silk fabrim, have been cheaper than the same size yarns made of rayon. For example, in 1950, 129,000,000 pounds or 39.4% of the acetate produced was in yarn sizes of 75 denier or finer, and priced at $1.03 for 75 denier and 81.11 for 55 denier, while only 45,000,000 pounds or 14.2% of the rayon produced that year was in fine sizes priced a t $1.09 and $1.48, respectively. As of this writing, acetate filament yarns have been further reduced, and these fine sizes are now 17 to 45 cents per pound cheaper than rayon. Based on its record growth and this favorable price relationship, it would appear that, acetate filamerit in competition with rayon filament will continue to enjoy a preferential share in satisfying the consumers’ expanding desire for more lustrous cloths a t cheaper prices. Without taking into account the current recession of the textile market and its possible curtailing effect on any future textile expansion, it hm been suggested (based probably on the projection of a growth curve) that in 1953 the then current annual acetate filament, capacity will be 401,000,000 pounds and the competiug rayon filament capacity will be 355,000,000 pounds, a relative increase, Yespectively, of 5 l / d % and 4 3 / & % over today’s basis. Now that I have to my own satisfixtion placed acetate in the more favorable position for further expansion in the ladies’ wardrobes, I have made it more vulnerable t o the oncoming attack of the avalanche of new fibers, creat*ed, as some distraught beings would have us believe, t o destroy and replare not only the natural fibers, but the rayon and acetate now so etrongly ent,renched in our textile economy. T r:in assure you nothing like this is going t o happen. FILAMENTS
Acetate, because of certain desirable qualities and a lower price’ is seemingly outdistancing rayon in the filament field, but each of these two products have qualities not possessed to the same degree by the other; also, rayon costs less than acetate in heavy sizes. Both acetate and rayon will coritinue t o expand, and the new synthetic filament yarns will have t o share with them whatever additional increment of lustrous fil~ment(*lotliesthe women decide t o buy. Nylon is the first and the only new filament yarn as yet available in large quantity for the luxury wear field Nylon consumption is now said to exceed t,he 80,000,000 pounds annually once achieved by real silk. Hosiery and fine knitt,ed and woven underwear take the bulk of this yarn which is available at, a price a t least double that of acetate and rayon. The total market for all man-made fibers has been expanded to some extent by the blending in a fabric construction of the higher priced nylon and the cheaper acetate and/or rayon. For example, in certain knitted tricot and woven fabrics, acetate filament blended with strong nylon improves the luster and feel of the cloth, and gives it increased dimensional stability because of the acetate filament, all at a lower price than could be obtained by use of nylon alone. The weaviug of fine acetate and rayon fabrics in the last 20 years made possible the ownership by millions of women of lustrous gowns, which before 1930 could only be purchased by those who could pay t,he high price for real silk.
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Before t’he advent o€ acetak, rayon, arid nylon, silk was cheap a t $4.00 per pound. Now in this category, man-made fibers are expensive at 932.00 per pound and the bulk of those used in silklike filament fabrics fall below $1.00 per pound for the raw yarns. Statistics show that in the last 20 years the per capita consumption of filament yarns has grown from 1pound per person t o about, 6.3 pounds per person in 1950. I n this field where man-made fibera have no competition from natural fibem, the future growt.11 is assured. I n my opinion nylon and the new acrylic and polyester filament, yarns will widen the market for fine filament, yarns in the next few years. It would be my guess that if in 1952 we have an annual production capacity of 850,000,000 pounds of acetate, rayon, nylon, and acrylic filament, by 1956 we would expect this to be increased by market demand to something over a billion-pound production capacity. While this estimate for filament yarri RXpansion in the next few years may appear t o some a8 very conservative in light, of some estimates in the papers, my thought, is that in the field for silklike fabrics a flattening out of the demand growth curve is likely to take place. -4billion pounds is a great, amount of yarn, if you consider that the yardage yield of 250,000,000 pounds of nylon is equivalent to t,he yardage of 750,000,000 pounds of acetate and rayon yarn, because of the fineness of the 40-denier nylon as opposed to the heavier 120-denier acetate and rayon. (Statistical information from which t,he est,iniat,es in this paper are derived are from TeztiEe Organon.) STAPLE
The larger and possibly more interesting field of short, staple fibers found in cotton, wool, and man-made spun yarn fabrics, in contradistinction to the cont,inuous filament fiber of luxurious cloths, will now be discussed. After the first World War, shortages and relatively high prices for wool and cott>onled t o the development and more rapid consumption of acetate and rayon staple fiber in Europe than in t,he United States. This is shown in the following table: Year
1951 1950 1950
Produrtion World capacity Europe United States
Staple Fiber,
.4pparel Vilaiiiciit Yarn,
53 59 32
47
v,
76
41 08
In the United States, staple fiber, which includes cotton am1 wool a3 w-ell as fibers of similar length manufactured or cut from long continuous man-made filaments, has grown in stature from 20 pounds per capita consumpt,ion in 1930 to 331/4pounds iii 1950. I n this growth we find very little man-made staple in 1930, so that, t,he present annual use of approximately 2 1 / 4pounds per capita represents relatively a phenomenal growth. Thc comparat ive figures are ahout as follow: Per Capital Consuinptioii, pounds 1930 1 9 60 18 27 2 4 Nominal 21/1 20 33’/a ~~
Cotton -tapir \~ool5tdplr
Man-niadp staple fiber Total
Rayon Acetate
Other t h a n rnyon a n d aoetatr Total
0.4 0.0 0,0 0.4
70.6
207
10.6
I29
Nominal 81 . 1
:i ‘I .~ 370
Considering the foregoing figures showing the per capita consumption, the following observations are of interest: First, the individual’s consumption of cotton in 20 years has increased by 50%. His consumption of‘ wool has douhled and his new use of the man-made fibers exceeds the amount of i ~ o ohe l consumed in 1930. Second, man-made fiber use today is made up of 56% rayon, 35% aretate, and 9% man-made fibers other than rayon and acetate
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
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S Y N T H E T I C FlBEll Today’s competitive prices per pound for various staple fibers are: acrylic fiber, $1.85; wool (top), $1.70; nylon, $1.70; cotton (New York spot), 42.4 cents; rayon, 42 cents; and acetate 42 cents. In discussing the competitive position of man-made fibers in the textile field where cotton and wool are so widely used, one is usually expected t o show that the natural fibers arc being replaced by the man-made fibers and that some time in the relatively near future fibers created by man will eventually replace wool and cotton. Xothing as yet would indicate the truth of such a philosophy. Recent history would show that as we kill off our sheep for lamb and mutton chops, the source of our wool supply diminishes, and because of a supply and demand situation, wool has become scarce and the price has gone up. Likewise, when the price of cotton rises t o the point where it rosts as much as either rayon or acetate t o procure, then these fibers at the same price will share some of the total business normally going to cotton. None of the old or new man-made yarns can duplicate certain characteristics of wool, and therefore it will not be supplanted a~ was silk. The use of the higher priced wool is likely t o grow as it is blended with the cheaper man-made yarns. During the last ten years of increasing consumption of acetate staple, although the price of acetate has ranged from 5 t o 19 cents above viscose rayon, one third t o one half of the acetate produced has been blended with rayon in percentages of from 20 to 80% and spun into combination yarns having different characteristics than either fiber alone. The cloths woven from these combination yarns and finished in plain and cross-dyed colors possessed a pleasing touch. In flannels, twills, and gabardines for suits, slacks, and sport shirts these combinations showed good wear, little distortion, and excellent resistance t o mussing or wrinkling. Fibers t h a t resist wrinkles better in fabrics are polyesters, nylon, wool, acrylics, and acetate. Of these acetate is the cheapest. Now t h a t the prices of acetate and rayon staple are the same42 cents per pound-an increased use of these combination yarns in sport clothes is assured. One disadvantage which the wool and cotton natural fibers have is that their price fluctuates over a given period of time much more rapidly than for man-made fibers. For example, in March 1951 when wool had climbed t o $3.70 from a low of $1.53 in November 1949, no one was surprised that with the rapidly increasing price of wool, acetate and rayon fibers had found increased use in men’s lightweight summer suits. This experience has shown t h a t these man-made fibers possess more woollike properties than had previously been supposed and the result is that they have made a permanent place for themselves in men’s clothing. In order to compare and show the potential value of the newly created fibers and their competitive place in relationship t o each other and t o both the natural fibers and acetate and rayon staple, a few outstanding properties of each of the several fibers under consideration will be outlined briefly. This should help evaluate the probably competitive penetration of the new fibers into the current textile distribution. The properties of the different fibers as outlined here are based to a large extent on my observational experience of the functional use of fabrics made from the various fibers and do not necessarily represent or coincide with conclusions of the fiber scientist. Cotton. With a dry strength exceeded only by nylon, cotton is the only textile under consideration which gains strength as it picks up moisture, whereas man-made fibers generally lose strength. The strong cotton fabrics thus have a recognized safety factor over man-made fabrics in dyeing, finishing, and laundering. Cotton fabrics take vat as well as direct dyes, and are therefore fast to light and washing. Untreated cotton fibers, in yarn and fabric, swell and shrink when wet or laundered, Cotton is regularly and commercially spun into much finer yarns September 1952
than any other fiber and in this con is a valuable feature. Some disadvantages are that cotton wrinkles badly and that its price at this time is the same as, and in fine cotton staple is higher than, acetate or rayon staple fiber. This, of course, will lead to some replacement of cotton in certain categories. For example, rayon staple may be used in yarns of 50’s and h e r , while acetate has an advantage in cotton-type cloths in numbers below 20’s. On the other hand, if the price of cotton does not increase materially, the tough wet strength and ease of dyeing of this product will continue to be preferred in fabrics. New finishing processes for increasing wrinkle resistance, abrasion, and dimensional stability will improve the desirability of this product. Wool. Among all staple fibers, both natural and man-made, wool is the only fiber having the property of fulling and felting. This property gives a unique advantage t o wool and worsted fabrics in that they can be woven in a n open construction on the loom and can be shrunk after weaving by fulling 25% or more in the warp and filling. As wool has a natural thermoplastic property, the shrunk cloth can be softened by heat and permanently “preset.” T o my knowledge there is no man-made fiber as yet which possesses this valuable property of fulling shrinkage. For this reason it is not possible to reproduce exactly a wool or worsted construction in man-made fiber fabrics. Some good fabrics simulating the appearance of wool or worsted cloths are practicable by weaving a cloth of man-made yarns in the number of ends and picks per inch found in the wool or worsted fulled or iinished cloth. However, this does not give a cover or crimped appearance of the yarns in the cloth as found in the worsted cloth being copied. While wool is the lowest in strength of the natural fibers, i t has high elastic recovery from deformation and possesses a high degree of resistance to wrinkling on days when the temperature does not reach 80’ F. with the humidity less than 70%. Wrinkling at high temperatures and high humidity is due t o the softening of the fiber with accompanying ease of deformation. Wool has been extremely vulnerable for some time, because of its high price, to competition from the cheaper man-made fibers. As we have noted, it has qualities which still make it the over-all preferred fiber for functional outerwear apparel fabrics and many of the upholstery and drapery fabrics. Nylon and the new polyester fiber with their high resistance to wrinkling, the new acrylic fibers with their bulk properties, and acetate staple, which comes so close t o wool in most properties, indicate that these man-made fibers will be blended with wool and used alone or in combination with spun rayon t o give some, but not all, of the wanted properties found in fabrics made of 100% wool. All of these new man-made fibers, experimentally at least, have been successfully dyed with acid or wool dyestuffs. The different rate of dye absorption for each of thesefibersprovidesconsiderable disadvantages in union dyeing with wool. The blending of staple nylon with wool in small percentages provides increased strength and higher abrasion resistance and undoubtedly will be used in increasing amounts. Rayon. Rayon staple fiber is produced in a fineness which corresponds t o that of cotton. It thus can be spun commercially into yarn sizes as fine as 70’s cotton count. Deniers as coarse as 20 are also made, and thus yarns in sizes corresponding t o wool and linen are practicable. Having a pure cellulose base like cotton, it can be dyed with fast vat colors. While the regular staple is not so strong as cotton in spun yarns, i t does have at least twice as much elongation as cotton yarn and fabric and garments can be laundered satisfactorily. Rayon is stronger than wool; therefore, good spun yarn blends are made of wool and rayon. Except as specially treated in finishing, rayon is low in resistance t o wrinkling and shrinks in washing. The relatively large expansion of poundage consumption of
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rayon staple outside the United States viould indicate that a similar growth in the use of staple rayon would occur here. Rayon staple and acetate staple are blended to produce a fine men’s and women’s suiting, and as has been noted, the production of this type of fabric is expected to increase. It is quite likely that rayon in increasing amounts will be blended with the new acrylic and polyeater fibers in the same manner as it has been blended lrith acetate. The observation has been made that the hydrophobic fibers are not comfortable to wear unless they are blended with a high percentage of rayon. It is claimed that because all of these new fibers, in dry veather and in dry heated rooms, develop a high static charge, causing the fabrics to cling or stick to the wearer and attract soil or lint, the blending of rayon staple with these fibers would reduce the over-all static charge materially. Acetate. hcetate is thermoplastic like wool and nylon and is produced in a range of deniers of ll/z t o 20. When cut into staple lengths, it contains 7 to 10 crimps per inch, which are partially recoverable after lorn load stretching. It has the same strength and stretch as wool when dry. While acetate is usually spun on the cotton system, it is especially suited to spinning on the wool or worsted systems, and because it has the same strength as wool, it is manufactured into the same counts or yarn numbers. Acetate was the first man-made fiber with a relatively low moisture pickup, having a regain of 6 > / ~ % .Garments of acetate, after being wet, dry much faster than n-001 or rayon. Acetate fiber is very soft, its pliancy being similar to that of wool. It, like wool, possesses a high immediate elastic recovery a t low load stretch, which in my opinion is the reason for its comparatively high resistance to winkling. Acetate staple, because of its special noollike characteristics and price equivalent to cotton and rayon staple, will have an increasing share in the over-all expansion of the staple fiber market. New acetate dyestuffs have recently been developed, which in acetate spun fabrics are of excellent fastness to light and atmospheric fading. Furthermore, since it is a relatively dry fiber, it can, like the new fibers, be dyed with acid wool dyes and v a t dyes under recently discovered methods. It would appear that blends of acetate of low specific gravity and the new polyesters would produce a cloth of new and favorable resilience characteristics having compatible dyeing qualities. A new development is the spinning of acetate staple from a dope solution containing extremely fast pigments; the staple is later made up on the worsted system into tops for further blending of colors before spinning. This solution-dyed fiber is also used on the cotton system, where the various colors are also blended together or blended with white rayon; the rayon component can later be cross dyed in the fabric for a large range of unusual color combinations. Nylon. Xylon staple has the highest abrasion resistance, elasticity, and fiber strengthof any fiber, and it reacts much like rubber in resisting wear caused by friction. In some spun nylon yarns and fabrics fuzziness develops in rubbing because of the escape of high elastic fiber ends. Kylon spun fabrics have good resistance to large wrinkling forces and a much lower resistance to small mussing forces. However, the wrinkles in nylon garments hang out, and the mussed garment can be smoothed out with light ironing after washing, because of nylon’s slow high elastic recovery. In 100% nylon fabrics the use of an extremely hot iron must be avoided, as otherwise a pressed wrinkle is permanently set. This results from nylon’s thermoplastic nature. This property in fibers such as nylon, the polyesters, acrylics, acetate, and wool can be turned to advantage in the formation of permanent pleats in fabrics containing these fibers. Very few 100% spun nylon fabrics are made because of their comparatively cold and unattractive hand. Further, spun nylon fabrics when made into draperies creep up or down with atmospheric changes. While 2174
there does not seem to be any advantage in using nyIon in a 100% spun fabric for apparel, the staple is being used in increasing quantities, but in small amounts, for blending Tvith wool, cotton, rayon, and acetate for the purpose of increasing the strength and abrasion resistance of the fabric. Sylon and the other new fibers of very low moisture content and relatively high elasticity have a tendency to develop minute bunches of fiber, sometimes described as “pilling,” probably due t o a combination of the elastic property of the fibers and the static charge. These minute bunches, when they appear in the yarn and show up in the cloth, are drsrribed as “neps.” Acrylic or Polyacrylic Staple. This fiber (the type with which I am familiar) has the lowest fiber density, a specific gravity of around 1.12 to 1.30, which in part accounts for a higher bulking quality than any other fiber. Fabric made of this fiber is warm and pleasant t o the touch. It is least affected by exposure to the sun and weather. It has relatively little resistance to soft wrinkles, and if the wrinkled fabric is steam pressed, the wrinkles are difficult to remove. While it softens a t temperatures above 400” F., it is plastic a t temperatures under the boiling point of water, and it has been recommended that the cloth should be preset in open width a t temperatuies around 200” F. in order to avoid wrinkling if the cloth is to be dyed later in rope form around 160’ F. The dyes suggested for use are selected arid or acetate dyestuffs. I n using acetate dyestuffs, it is difficult to get the same depth of shade as can be obtained with these dyes on acetate fabrics. It has been found possible to dye these fabrics with selected wool or acid colors, and in dyeing, these colors go on much slower than they do on wool and are generally not as color fast. Completely satisfactory commercial methods of dyeing have yet to be developed and it is possible that as different forms of acrylic fibers are introduced in the market, a fiber will eventually be created which can be dyed satisfactorily, or continued dyeing research will solve this problem for the type of acrylics now available. The natural color of most of the acrylics is creamlike. This color seems to darken or yellow a t dry temperatures of over 250’ F. The moisture regain a t 65’ F., 70% relative humidity, is somewhat between 0.5 to 1.76%. I have been shown fibers which have 2l/2 t o 3 grams per denier tenacity with 35% elongation, and others with a strength of 3 to 4 grams per denier and an elongation of 14 to 16%. The acrylic fibers, having high strength, good dimensional stability, low absorption, and high bulking power nil1 eventually have a place in the industry. As they come nearer in price to acetate and rayon, they -will finally be substituted for some of the constructions made of these fibers. I have not as yet seen sufficient evidence of superiority of fabrics of these acrylic products to indicate that they will do more than share in the over-all increase in the market for all staple fibers. I believe the largest use for this fiber , its extra strength and high bulking is in blends with ~ o o 1 where power will provide a warm weight fabric with a very small percentage of wool in the blend. Polyester Staple. This fiber is unique in that it is the first man-made fiber to have built in its structure a large measure of combined stiffness and elastic recovery from bending. The resultant fiber when woven into cloths of proper construction, does not muss or wrinkle in normal wear, a t high or low temperatures, or under dry or wet conditions. -4s the fiber is thermoplastic, heat-set tailored creases in pants are little altered after many days of wear. As shirts made of this fiber are usually hand-washed a t home because they do not require ironing, there is no shrinkage after washing in water a t a temperature below the boiling point. However, my experience with sending a polyester shirt to the commercial steam laundry is that the garment shrank badly and after eight or ten xashings was too small for comfort. The explanation for this is probably that the fabric, before being made up into
INDUSTRIAL AND ENGINEERING CHEMISTRY
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the garment, had not been preset a t a high enough temperature and that the laundry used boiling water or steam at temperatures above the boiling point, where shrinkage of 5 to 6% will take place. A sufficient range of colors which are fast t o light and washing has yet t o be developed. Some of the new dyes, developed for fast colored acetate, have been successfully employed in dyeing this fiber. A relatively longer time of dyeing has had to be used than with other fibers to get the depth of color desired, Recent developments would indicate that polyester fibers can be dyed satisfactorily in wanted colors with adequate fastness by using special dyeing processes with temperatures above the boiling point of water. It would appear that this new fiber will eventually be consumed in large quantities in competition with all other fibers in the staple fiber market. Introduced a t a relatively high price, it should find its greatest advantage when used in small quantities in blends with other fibers. One of the new fibers which will find a place and compete with all other fibers, particularly for products which require nap, such as blankets, is the staple fiber spun from a copolymer of acrylonitrile and vinyl chloride. For convenience, this is usually included in the polyacrylic group. However, its properties are in many respects quite different from fibers made from the acrylic polymer or copolymer. This fiber has a high resilience and warmth, dimensional stability, rapid drying qualities, and does not support combustion, which makes it valuable for many uses. The protein fiber is a desirable product for use in blending with wool. While it does not have the wrinkle-resistant properties of the other fibers, its soft nature and the fact that it is a protein, like wool, and thus can be dyed with the same dyestuffs, is favorable. CONCLUSION
Looking to the future, it is my belief that the staple fiber market will continue to grow. Assuming that a continued rise in the standard of living predicates an increased use of apparel, as the human need for clothes is second only to food, I have tried to show
e ompetition among the various fibers. I n the staple field there has and will be again a n unsatisfied demand for any and all fibers, At the present time the cost of the natural fibers is relatively too high, and as long as this situation prevails, the further rapid development of man-made staple will be favored. Rayon and acetate, with their prices more closely keyed to those of the natural fibers, will continue to expand. The newly created fibers entering the field a t high prices, but enjoying Some attributes of superiority not possessed by the fibers now being consumed, will have for the next few years relatively rapid growth. You have all, no doubt, noted the recent estimates of an installed production capacity for the newly created fibers of around 156,000,000 pounds in 1953. Based on my study of the past growth curves of the different staple fibers, as affected by the continuing competition of cotton and wool, I would estimate that the present man-made staple fiber capacity of around 400,000,000 pounds might well be increased to three quarters of a billion pounds on a n annual basis by 1956. At the beginning of this discussion on staple I indicated that in Europe the annual production of staple fiber was running slightly ahead of t h a t of apparel filament yarn, while in the United States in 1950, it represented only 32% of the combined total. I have estimated the filament yarn production by 1956 as 1 billion pounds, and I now estimate the man-made staple fiber capacity as 750,000,000 pounds or a total of 1.75 billion pounds. The 1956 estimated capacity would show staple fiber production a t 43% of the combined staple and filament yarn, and as has long been expected, we will commence in this country to overhaul the head start which Europe has had on us in the use of man-made staple fiber. I have already mentioned that the United States per capita consumption of man-made staple in 1950 was 2'/4 pounds. M y staple estimate would indicate a possible per capita consumption of around 4'/2 pounds for 1956. I n my opinion, acetate will absorb the impact of the new man-made fibers, and by 1956 will have a large part in the estimated 1.75-billion-pound production of filament and staple. RECEIVED for review March 31, 1952.
ACCEPTEDJuly 3, 1952.
Inside View of Machine Used for Dyeing Dyne1
COURTESY CLIFFSIDE DYElNQ CORP.
September 1952
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