Meet the Azlons from A to Z: Regenerated & Rejuvenated

(click on pictures for a larger view)

Researchers from the beginning of time have sought new sources for textile fibers. In their quest to improve performance of natural fibers, the laboratory became their field of dreams and fiber chemistry was born. Robert Hooke, an English experimental philosopher, stated in 1664 that an artificial glutinous substance similar to the liquid gum which the silk worm excretes and spins into silk filaments might be found from which fibers could be drawn out. This was echoed in 1710 by Rene Reumur, a French philosopher, who suggested methods by which an artificial silk might be approached using liquid gums and resins for making silky filaments

Once Count Hilaire de Chardonnet commercially produced nitrocellular rayon in 1891, the race for manufactured fibers accelerated. The test tube has enabled chemists worldwide to achieve momentous breakthroughs in textile technology which has resulted in rayon, nylon, polyesters and new generations of manufactured fibers. At the beginning of the 20th century, manufactured fibers accounted for 1% of the American fabric market; now into the 21st century it is more than 70%.

Little attention has been given to a group which was and is fiber source of protein -- azlons, referred to previously as not-natural proteins or prolon or protan. Through the marvels of experimentation these fibers helped a war effort, and now after a long period of declining activity are again becoming a valuable and economical source of textile and industrial applications.

It is important that textile collectors be aware of azlons as many of their vintage fabrics, quilts and garments from the latter 1930s through early 1960s thought to be wool or rayon could be azlon blends which simulate wool.

Azlon Overview

Azlon is defined by the Textile Fiber Products Identification Act as the generic name given to regenerated fibers of peanut, milk, corn [zein] and soybean, fibers which have been broken down from their original form and reassembled into fiber structure again.

The first attempt at producing a man-made protein fiber was Vandura silk introduced in 1894. It was not successful as a cloth but led the way to sparking interest in creating stable protein fibers. Another attempt in 1904 by a German chemist, Todtenhaupt, flopped as the product was not pliable; fibers would swell, soften and stick together during the dyeing process. Between 1924 and 1933 an Italian, Antonio Feretti, succeeded in creating useable casein protein textile fibers. Germany, England, Holland and the United States soon followed with their commercial productions. At the same time research began yielding methods for converting protein from peanuts, corn and soybeans into textile fibers.

Spinneret in action, often called the birth of man-made fibers. - The Modern Textile & Apparel Dictionary

The process in manufacturing protein fibers is somewhat similar to rayon production and azlons outside USA were and are considered regenerated protein or regenerated cellulose. The steps include extracting protein from original source and processing into a spinning solution that can be extruded through a spinneret. Fiber is coagulated in a chemical bath and stretched to produce sufficient strength and finally treated in a hardening bath to impart dimensional stability and chemical resistance.

Protein fibers are weaker and therefore have to be blended with other fibers for stamina. However, the chief desirability is their wool-like properties which add warmth and softness to otherwise stiff and cool cloth, and have an economical aspect as they cost less than wool to produce and for consumers to purchase.

Azlons have not been made in this country since 1973 and few are now made overseas. One of the major reasons for past declining textile production worldwide was the introduction of stronger and softer man-made fibers after WWII and an ongoing objection to cutting into valuable food supplies.

However, the market has begun to pick up as the search for perfect fibers intensifies -- those that are derived from low-cost natural resources rather than crude oil, which are clean and environmentally friendly and comfortable to our skin.

Japan successfully grafted milk protein with acrylic in the early 1970s to produce Chinon, very expensive to produce and no longer in production. Also from Japan, Unitika developed polymer-based proten fibers, called chitin, which are regenerated from the protein of outcovering of beetles which the firm believes will have specialized medical use for sutures. Corn is making a big splash with textile production of polylactic [PLA] fibers made from cornstarch and various cellulose solutions.

The following chart will help to map and put azlons into perspective for you. Highlighted fibers are featured in this column.

Textile Fiber Classification
I. Natural Fibers
II. Man-made or Manufactured Fibers
  1. Non-thermoplastic - does not melt; scorches or burns at high heat
    a. alginate [seaweed]
    b. cellulosic
    c. mineral
    d. protein
      - azlon fibers up to the early 1960s
        ~ animal
          . casein [milk] protein - Aralac, Lanital, Merinova, R-53, Caslen
        ~ vegetable
          . peanut protein - Ardil; new research
          . soybean protein - experimental, new research
          . corn [zein] protein - Vicara; new research
    e. miscellaneous
      - chicken feathers
      - cottonseed protein

* Casein [milk] protein

Casein dates back many centuries when it was used as a binder for paints -- paint with casein applied to 14th and 15th century churches still appears bright and unfaded.

Proteins are obtained from skim milk, evaporated milk and condensed milk. There are about three pounds of casein in every 100 pounds of milk.

When cut to staple-length fiber casein many properties of wool. Fibers are white, fluffy, springy and have a pleasant odor. When blended with other fibers casein added a soft draping quality and resiliency to fabrics. Fiber was blended with wool for creating felt and with spun rayon, wool, mohair and cotton for attractive woven and knitted fabrics in a variety of weaves, textures and prints.

Even through casein fiber lacks certain desirable qualities of wool it was a way to replace wool at a lower cost. When mixed with rayon and wool, casein helped in the conservation effort during WWII as a wool substitute.

Casein fibers cannot be distinguished from wool fibers by chemical or burning tests, only by microscope. Because chemical composition is so similar, casein burns like wool with odor of burning hair, has no surface scales like wool but is smooth and round when viewed under a microscope, is damaged readily by alkalies and mildews easily.

Though caseins can be laundered with care the same as wool, they lose strength when wet and must be handled gently. They cannot be kept damp for any length of time due to quick mildewing. Three successful brandnames were Aralac in America and Lanital and Merinova in Italy.

Ground casein is poured into trap door, treated with chemicals and heated in huge vats to form a solution which is forced through spinnerets; washed, dried, cut into staples and baled to yarn-making plants for spinning and blending. - America's Fabrics

Textured drapery made from soft casein yarns combined with other fibers. - America's Fabrics

Montgomery Ward's S/S 1942 catalog featured classic felt styles of 94% new wool and 6% casein fiber. Colors choices were black, flag red, navy, dusty rose, dusty blue and beige. $2.48 and $3.98 respectively. - Courtesy Shirley McElderry

Lanital was the first successful protein fiber from milk casein. Antonio Feretti was granted a patent for this fiber from the Italian government in 1935. It was named Lanital [lana = wool +ital = Italy], and manufactured by Snia Viscoca which called the fabric a fancy rayon. It lasted into the early 40s and superceded by Merinova which was was used to blend with rabbit hair in the production of felts. Merinova was discontinued in the late 1960s.

Fibers of both fabrics were very similar to wool and could be dyed by the same processes, and like wool they were easily damaged by alkalies. Both had a resilient wooly feel but were not as strong and firm nor as elastic as wool. Moths would not attack and shrinkage was not as much as wool but fibers mildewed easily when damp, an inherent characteristic of protein fibers as noted earlier.

Cross sectional view of Lanital under a microscope. - Kansas State Ag Bulletin 300

1942 fabric of 50% wool serge, 50% Lanital. - Kansas State Ag Bulletin 300

These are raw fibers of Merinova, a brandname, blended with rabbit hair the production of felts; usually particularly felts for hats. Color is champagne but deepened here to enhance image composition. - Courtesy Mary Humprhies

Aralac was detailed in the November-December column but is repeated here for reader convenience as there is additional information.

A patent was granted in 1937 to the United States Department of Agriculture for making a casein fiber by a somewhat different method than Lanital. Aralac was developed by the American Research Associates, a scientific research division of the National Dairy Products Corp.

A useable fiber was developed and ready for the market in 1940, just in time to serve as a wool substitute during WWII. Its name was derived from ARA = American Research Associates + lac = Latin for milk.

Aralac was blended with rabbit fur in making felt hats and with wool, mohair, rayon and cotton in varying proportions for fabrics and garments. Although clothing in this fiber was available as late as 1947, the impact of man-made fibers following the war caused the demise of this fiber in 1948 as it could not compete with the low price of new synthetics. Plus when damp, this fabric smelled like sour milk, causing many consumer complaints, a quite common, familiar ailment within the casein family.

- Fabrics and Dress

R-53 appeared around 1941; R for research and 53 indicating it was the 53rd fiber tested in a search for a fiber which was suitable to manufacture felt hats. This fiber was finer than Aralac and was used to blend with rabbit fur in making felt for hats. Little information is available. It was listed by this name as late as 1953 but seems to have disappeared. Possibly the fiber might have been renamed or absorbed by Merinova or failed to survive as a competitor.

Caslen was a trademark of Plastic Products, a division of Rubberset. It was developed as a curled and resilient replacement for horsehair in upholstery. It appeared on the market in the late 1940s and according to glossary listings, was off market by the early 60s. Another brand from Great Britain was Fibrolane, discontinued in 1965.

80% spun rayon and 20% Aralac plaids and checks, $1.94/yd from Sears F/W 1944-45 catalog. Dry cleaning recommended. - Courtesy Sharon Stark

Spun rayon 80% and Aralac 20% flannel solids, $1.56 and 88¢ /yd from Sears F/W 1944-45 catalog. Colors: brown, purple, beige, green, gold, aqua, red, black, blue. Dry cleaning recommended. - Courtesy Shirley McElderry

Sears S/S 1943 called these plaids the new animal fiber. 80% spun rayon, 20% Aralac. $1.49/yd. Suit and dress made from fabric were McCall patterns. Dry cleaning recommended. - Courtesy Betty Wilson

Floral housecoat of spun rayon and Aralac, blue or rose ground, $4.98, Mont. Ward S/S 1945 catalog. --Courtesy Shirley McElderry

Tailored flannel bathrobe of 50% spun rayon and 50% Aralac, copen blue & scarlet, $8.95, Sears F/W 1944-45 catalog. - Courtesy Shirley McElderry

Spring lined coats of 70% spun rayon and 30% Aralac twill; navy, black; $9.98; Sears S/S 1943 catalog. Sears guaranteed this product. - Courtesy Shirley McElderry

Super Charmalac dresses of rayon and Aralac, washable, pre-shrunk, $3.98. #1 coral red, med. blue; #2 pine green, coral red, navy; #3 aqua, melon rose, gold; #4 cocoa brown, aqua, violet. Sears F/W 1944-45 catalog. - Courtesy Shirley McElderry

Post-war Aralac/rayon Ara-fab Fashions from National Bellas Hess F/W 1946-47 Catalog

For the Jr. Miss - grey w royal blue bands, royal w Am. beauty rose, Am beauty rose w royal; jr. sizes 11-19, $4.98

Dress suit in grey w Am. beauty rose skirt, red w blk skirt, royal with Am. beauty rose skirt; misses 12-22, $5.98

Casual wear in kelly w gold or luggage w gold; misses 12-22; $5.98

2-pc jerkin set embellished with felt motifs; kelly, navy or purple; blouse not included; $4.98; misses 12-22

Embroidered dress suit with white detachable collar; blk, soldier blue or autumn wine; womens 36-53; $6.98

* Peanut protein

Peanut textile fibers, part of the pea family leguminosae, are derived from the high protein of peanut after oil is removed. Their use has not seemed to fare well in commercial cloth ventures. While they have a soft hand and high loft they are low in dry and wet tenacity.

Britain was the first to produce a commercial cloth, Ardil. At one time peanut textile fiber development was a hot topic in our country, and one company was all set to invest in such a venture but at the last moment switched to zein [corn] research.

Ardil was made from peanuts. In the 1950s it was heavily marketed for industrial and domestic uses. Dresses, suits and pajamas were promoted with the slogan Happy families wear clothes that contain Ardil. - The Dolphin, University of Southampton, UK

There appears to be renewed interest both in America and overseas to commit to peanut fiber research. The National Programs branch of the Agriculture Research Service is conducting tests to further understand the changes induced in peanut proteins during processing and the effect of these changes in reducing the allergenicity of peanut products.

Ardil was an artificial wool fiber spun from vegetable protein obtained from groundnuts. It was part of a research program conducted by the British government which ended in an ill-fated scheme to develop groundnuts as part of an East-African economic development program.

According to a book about the Imperial Chemical Industries [India] Ltd. by Carol Kennedy, the fiber was called Ardil after the name of the research chemist, David Trail, combined with the word wool. A pilot plant was built in 1940 by ICI to test the product and once satisfied, it built a full production plant.

During the testing period, a sample of Ardil was sent to the director of ICI's paint and rubber plant in India, The Alkali and Chemical Corporation of India Ltd., for evaluation. To test its strength and wear, he had a carpet woven from the fiber to see how it would withstand the daily rigors of being walked on. He still has the carpet which shows little sign of wear and tear.

At its peak capacity in 1951, the plant was producing 10,000 tons of fiber. However, Ardil was not a successful venture for ICI and manufacturing ceased in 1957. This was due in part to Ardil not having as wide a range of uses as the other fibers that ICI produced which were made from cellulose, and that it was perhaps developed at the wrong time with the intervention of WWII shortening its life span.

* Soybean Protein

As early as 1937 soybean fiber was showing promise of usefulness in the textile field. It was the first textile filament to be spun from the protein of vegetable origin. Soybean is exceptionally rich in protein, nearly 50% is protein.

Initially the fiber was manufactured by crushing beans under pressure and extracting oil. The protein in turn was extracted by passing the meal through a saline solution; it was then combined with various chemicals to form a liquid about as thick as molasses to be used in a spinning solution. This was forced through a spinneret containing as many as 500 holes and the filaments were then hardened in an acid bath.

Early soybean fiber research was a problem for scientists who were unable to produce firm, tough protein filaments which would resist wear and deterioration. This was due to a molecular arrangement very different from the structure of natural fibers.

The fiber was white to light tan color and had the appearance and texture similar to wool and silk, was warm and soft to the feel, had natural crimp and a high degree of resiliency. It did not absorb moisture as easily as wool or casein and thus didn't mold as readily as casein fiber. Because its chemical properties were similar to wool it could be dyed the same as wool.

It blended well with wool, rayon and cotton and was woven and knitted into goods by the usual textile methods. Ford Motor company experimented with it for car seats in the early 1940s which proved to be quite satisfactory. Fiber was used also for suitings and other upholstery fabrics but there was never any major production. As with other azlons, fiber fell victim to its faults and was overtaken by the new post-WWII synthetics.

Since 2000, China claims to have taken the world lead in the industrialized production of soybean fiber protein [SPF], calling it the healthy and comfortable fiber of the 21st century. A new process which involves wet spinning after extraction and changing the space frame of the protein by adding a functional agent has created a fiber which produces a fabric of such soft luster that it rivals silk and cashmere. Its unique qualities provide absorbing and releasing moisture for ventilation and warmth and yarns can be mixed with wool, flax, silk, cashmere and spandex to produce fashionable underwear and clothing. China claims that many countries have shown deep interest in this newly revamped fiber.

Soybean fibers ready to be blended with other fibers and spun into yarn at Ford Motor Co., early 1940s. - America's Fabrics

Yarn made from pure soybean protein fiber. - China Products

Car upholstery from soybean, 1941-42. - Kansas State Ag Bulletin 300

For further soybean information see http://www.spftex.com/aboutus/company.html

* Corn [zein] Protein

One of the few well-understood plant proteins is zein, an abundant protein in corn seeds. Zein makes up 39 % of kernel protein or about 4 % kernel weight. It resists microbial attack and cures with formaldehyde to become essentially inert, is water insoluble and thermoplastic. Thus it has several properties of industrial interest such as the ability to form fibers and films that are tough, glossy and grease and scuff resistant.

As a textile fiber it is non-petroleum based, naturally recyclable, non polluting and has a silky luster and smooth feel. As an industrial fiber its main current use is a water-impermeable coating for pharmaceutical tablets, nuts and candies. It also functions as a cork binder for gaskets and bottle cap liners, a binder in ink, a varnish and a shellac substitute. And with renewed interest in corn fiber, polylactic acid fibers are creating a stir in the clothing sector.

Vicara 1948-58 reads the tombstone. In the late 1940s the USDA Northern Regional Research Laboratory in Peoria IL was successful in developing zein into a textile fiber. Scientists generated the fiber by dissolving zein in alkali, extruding the solution through spinnerets into an acid coagulating bath, and then curing the product with formaldehyde.

Zein fibers were washable and dyeable with some of the good properties of wool, smoother, excellent hand but they had to be blended as fibers could not stand on their own due to percentage of shrinkage and were not as strong or wear resistant as synthetic fibers.

Raw fibers of Vicara, soft as cashmere. Color is champagne but deepened to enhance fiber structure. Blended with rayon, wool or nylon or all three for wearing apparel. Its brief lifespan was 1948-58. - Courtesy Mary Humphries

The Virginia-Carolina Corporation commercialized zein-based fiber as Vicara, producing about 5 million pounds in 1954. The fabric sounded too perfect - it was described at soft as cashmere, non-shrinking, resistant to wrinkling, pilling and matting, odorless when wet, non-felting and highly absorbant. It made up well into fabric and draperies. However, the company discontinued manufacture in 1958 due to the advent of better performing synthetic fibers.

Textile author Mary Humprhries remembers Vicara as soft, absorbent and quite a golden color. While analyzing a fabric comprised of 25% each wool, Vicara, Cuprama (cuprammonium rayon) and nylon in the 1950s she recalls it was fun to make dye formulations for and "we in the lab called it fiber stew. This combination made wonderfully soft, absorbent, very long-lasting and not-too expensive socks."

Polylactic acids - is this the perfect fiber of the future? As with soybean research, the corn field is currently a source of rejuvenated advanced research in producing an ecological corn fiber which uses a natural product, corn. This is a biodegradable synthetic fiber [polylactic acid fiber or PLA] which is made from raw materials of cornstarch and various forms of cellulose.

Although still at the early stages of production, polylactic acid fiber is thought to be the new fiber of the 21st century. The new method of processing allows fiber to be blended with cotton, rayon and wool for a wider range of applications to a variety of textile products such as fabric, knits for shirts, casual wear and uniforms, yarns and nonwoven fabrics. The safety of polylactic acid resin in corn fiber has also been confirmed through field trials and skin irritation tests. Another feature is minimal maintenance for clothing - no ironing nor tumble drying.

Cargill Dow recently completed construction of a polylactide polymer plant in Blair NB which can produce 300 million pounds of PLA per year when running at full capacity. The company will continue to use the NatureWorks trade name for its proprietary fiber. Kanebo Gohsen has already been working on the merchandising of its corn-based fiber LACTRON as a new fiber material for both clothing and non-clothing use.

For more on corn research, see this new brandname Ingeo http://just-style.com/nd.asp?art=28171&dm=yes

Fashionable casual wear and suit made of 100% corn fiber with wool or cotton offer lightness, stability and anti- wrinkling. -Kanebo Goshen Ltd.

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My thanks to textiles instructor Pauline Bulawa whose early 1970s textile classification outline is responsible for the idea behind this column;to Shirley McElderry, Sharon Stark and Betty Wilson for time spent researching their catalogs and magazines; and to textile author Mary Humphries for additional information..

Footnote to vintage fabric collectors:

For those who are serious about fiber content of their fabrics made during the mid-1930s through early 1960s, you might want to research textile science literature of that time which contain microscopic views of protein fibers. It might prove interesting to compare and learn if any of your quilts, garments and fabric are protein blends. Fibersource.com provides links to the American Fiber Manufacturers Association [AFMA]and other manufactured fiber websites which may be able to assist you.

A forthcoming project also should be of interest. Research for a book on regenerated protein fibers made in the USA in the mid-twentieth century as a substitute for wool is being conducted by Mary Brooks of the Textile Conservation Centre at the University of Southampton, UK. She has been awarded a scholarship at the Getty Conservation Institute, Los Angeles, and will begin research work this summer.

Her study will focus on locating surviving examples of these forgotten fibers to characterize their degradation patterns as well as exploring the history of their development and use. This work builds on her previous research into ICI's regenerated protein fiber. Anyone who remembers having Ardil or other protein garments, carpets or upholstery is invited to contact Mary at the Textile Conservation Centre. Email tccuk@soton.ac.uk.

References

General Information about the Protein Group
America's Fabrics, Bendure & Pfeiffer, 1947,
Introductory Textile Science, Marjory Joseph, 1972
Modern Textile & Apparel Dictionary, George Linton, 1973
Synthetic Fibers and Textiles, Bulletin 300, Hazel M. Fletcher, Kansas State College of Agriculture and Applied Sciences, April 1942
Textile Fibersr and Their Use, Katherine Paddock Hess, 1948
Information re Mary Brooks forthcoming book: dolphin.soton.ac.uk/Feb2002/ardil.html

Casein, Aralac, Lanital, Chinon, Chitin
America's Fabrics
Fabrics, Grace Denny, 1936, 42, 47, 53, 62
Fabrics and Dress, Rathbone & Tarpley, 1946
Fabric Reference, Mary Humphries, 1999
Kansas State College Bulletin 300
New Zealand milk, China Products: chinaproducts.com/tu.htm
Textile Fibers and Their Use
Understanding Textiles, Phyllis Tortora, 1992

Peanut Fiber & Ardil
University of Georgia peanut statistics: angelfire.com/tn2/minsrecipes/IndigenousPlants/Peanut.htm
Big Idea: bigidea.org.uk/poa/Products/Products
Fairchild's Dictionary of Textiles, 7th ed., 1999

Soybeans
America's Fabrics
China Products

Vicara & Polylactic Acids
America's Fabrics
Fabrics
Modern Textile & Apparel Dictionary
Kanebo Goshen Ltd.: kanebotx.com/english/new/corn-f.htm
National Academies Press: nap.edu/books/0309053927/html/35.html
Shenshobu Keizai Shimbun: textileinfo.com/en/clean/cleantech/10.html