The knitting process begins with the yarn. Your project will come to life by the inherent qualities of the yarn, and how it is knitted, that is the combination of the yarn, stitch pattern, and the tools. For this post, I want to address fibers, the raw materials of yarn, and in a later post yarn construction.
As you gain knitting experience, you will better understand fibers and their various properties. You will certainly find the ones you love. I wrote about my fave in “My Love Affair With Wool”. The following is a short introduction to fibers.
Getting To Know Fibers
Fibers are classified as natural consisting of vegetable (cellulose) or animal (protein) fibers, and manufactured consisting of cellulose based fibers, synthetic fibers, and metallic fibers. There are only a few synthetics useable for hand knitting yarns. Blends are combinations of different types of natural and/or manufactured yarns.
Natural Protein Fibers
WOOL Wool is by far the most popular and so much so that knitters term all yarn wool no matter what the fiber content. Wool is the hair fiber that comes from sheep. There are more than 200 breeds now in existence. The best quality for textiles come from breeds such as Merino, producing a luxurious, fine, soft fiber, and a favorite to knit with. Merino sheep dominate the world sheep industry. An Icelandic breed produce a coarse, scratchy fiber that is highly durable and popular for outerwear.
Wool is desired because of its special properties. It is resilient and elastic making it easy to knit with. Wool springs back into shape, wears well, and resists wrinkles. Wool is unique because it is comfortable to wear in both warm and cold climates. It has excellent insulating properties due to its natural crimp or wave, trapping air. In addition, it can absorb up to 1/3 its weight in water shedding liquid easily, and still feel dry; making it a favorite for items such as hiking socks and outdoor sweaters.
The surface of wool is covered with scales that vary in size and determine the fineness and coarseness of wool. Fine, soft wool has as many as 2000 scales/inch, whereas coarse wool has as few as 700 scales/inch. These scales are responsible for the “itchy” feel some people complain of, particularly with coarse yarn. The scales are also responsible for the felting or shrinkage of wool. Felting can be deliberately done through a process that includes heat, moisture, and friction, forming a matted fabric. Superwash is a finishing process that alters the scale structure so that wool can be machine washed.
Wool is susceptible to damage by moths. Today, most wool is moth proofed by manufacturers so it is rare to see this problem. Wool protein is also damaged by bleaching agents, so white wool should never be bleached.
SPECIALTY HAIR FIBERS
MOHAIR This fuzzy fiber is shorn from the Angora goat, not to be confused with angora from a rabbit. Kid mohair is the hair from the first two shearing of young goats. The fiber size increases with the age of the goat, thus a young goat yields fine, silky fiber used for clothing, and an older goat has thick, coarse fiber used in carpets and outerwear. It’s durable, lightweight, and warm, with similar properties to wool. Mohair is often blended with wool, cashmere, alpaca, silk or a synthetic to help the fibers cling together.
Beginner knitters may find yarn with a large percentage of mohair hard to work with; the long fibers entangle, making it difficult to take apart. The bloom or fluffiness of the yarn hides a highly textured pattern.
CASHMERE China is the largest producer of cashmere. Of the hair fibers, cashmere is one of the most luxurious and costly to produce. The down fiber is combed from the bellies of the Kashmir goat found in the high plateaus of Asia, and is collected only in the spring. Cashmere hand knitting yarns are often blended with wool to cut down production costs. Cashmere is incredibly soft, resilient, lightweight, and warm, but is more easily damaged than wool.
ALPACA Alpaca is a member of the camel family found mainly in South America. Today, other parts of the world are breeding alpacas. There are two types of Alpaca: Huacaya, a dense, soft fiber; and Suri, a long silky fiber. Alpaca fibers are typically long, durable, and lustrous. Alpaca has excellent warmth and insulation; warmer than wool. This fiber comes in 22 natural colors with more than 300 shades from blue black through brown black, brown, fawn, white, silver grey, and rose grey. White is predominant and can be dyed in the largest range of colors.
CAMEL HAIR Camel hair comes from the Bactrian two humped camel in Asia. The under hairs are fine and soft and are used for yarns. The natural colors of camel are frequently maintained, as the fiber is not very receptive to dye. This fiber is often found blended in yarns as neutral colors.
ANGORA Angora is a very soft, fluffy, warm fiber, and high quality angora is combed from rabbits rather than shorn. This fiber is a very short staple and is difficult to spin, so it is often combined with other fibers. Because it’s a very short staple, it sheds as much in the yarn form as it would from the animal. As with mohair, it is difficult to see patterns because of the fluffiness.
The above hair fibers are the most commonly found in hand knitting yarns, but there others you might come across including fiber from llamas, another member of the camel family. This fiber is often blended with wool. Qiviut from musk ox is a very fine, soft, warm fiber mainly used by the Inuit peoples, and has recently become a luxury yarn with a high price tag. The vicuna, found in South America looks like a miniature llama and is one of the softest of the hair fibers. It is rare and costly, and a vicuna coat is comparable in cost to a fur coat. Mink, chinchilla, reindeer, beaver, and even dog hair can be spun to produce yarn.
SILK China is the leading producer of silk and legend suggests it was discovered by a Chinese empress. Cultivated silk is raised under controlled conditions called sericulture, an expensive and labour intensive process. A variety of moths produce silk. The larvae live on mulberry leaves, and the cocoons are subjected to heat to unwind the fine, lustrous filaments in one continuous strand. Wild silk worms produce a coarser fiber, with an irregular surface (tussah silk), less lustrous than cultivated silk.
Silk is a strong fiber, an excellent insulator, and dyes well in bright colors. Although silk is a strong fiber, it has other characteristics which make it less durable and not as versatile as wool. Silk is not as resilient or flexible as wool. It has a tendency to stretch with wear and is stiffer to knit with than wool. Silk tends to fade more readily with each cleaning, and over time may develop a fuzzy surface. Because of the expense of producing 100% silk yarn, it is often found blended with other fibers, adding a sheen.
NATURAL CELLULOSE FIBERS
COTTON Cotton is the most widely used fiber in the world, but less popular for hand knitting yarns. Cotton is a seed fiber attached to the cotton plant, and grows best in warm, humid climates. Cotton is classified according to its fiber or staple length, grade (color or brightness), and fineness. The fiber length is most important to the quality of cotton. The longer the staple as in Pima and Egyptian cotton, the better the fiber properties. These types of cotton are very soft. Organic cottons and genetically engineered colored cottons (no dyes) are available today.
Cotton has high strength and is stronger when wet, making it easy to launder. Generally, cotton has to be treated to prevent shrinkage. Cotton has poor elasticity and low resiliency so it feels stiffs when knitting. With cleaning and wear, a cotton garment tends to get a worn fuzzy appearance. A wool garment will be enjoyed for many years longer than one made of cotton.
Mercerization is a chemical finish used on cotton that adds luster and improves its dyeing properties. Mercerized cotton is also stronger and less prone to shrinkage.
Cotton does not attract moths, but mildew can be a problem. Garments should be totally dry before storage. Cotton blends well with other fibers including wool, rayon, and synthetics.
FLAX (LINEN) Linen is the term that describes fabric that is made from the stem of the flax plant, a bast fiber. The proper name for the fiber is flax, but “linen” is commonly used as a generic term to describe the fiber and woven textiles.
Flax is the oldest textile fiber, used in the ancient civilizations around the Mediterranean as it made a cool, breathable fabric. It is uncommon to see 100% linen hand knitting yarns, as it requires a great deal of processing. Flax is quite stiff to work with due to its low elasticity and resiliency. These properties also cause the extreme wrinkling of linen fabric. Flax is often blended with other fibers, particularly cotton to make it more useable as a hand knitting yarn.
Flax is the strongest of the plant fibers and like cotton is stronger when wet. Its absorbency is higher than cotton and can withstand higher temperatures than cotton, making it is easy to care for.
RAMIE Ramie comes from the perennial shrub, ramie. The fibers have similar properties as flax; high strength and poor elasticity. The fibers are very stiff, almost brittle, so it is blended with silk, flax, or cotton for hand knitting yarns.
HEMP Hemp is the name of the soft, durable fiber that is cultivated from plants of the Cannabis genus. New modifications by manufacturers have improved the properties of hemp, making it useable as a hand knitting yarn on its own or blended.
BAMBOO Bamboo fiber comes from the pulp of bamboo grass. It is considered a sustainable product as it is quick growing, and usually requires no pesticides or herbicides; farms are easily kept organic. The fiber resembles cotton in its natural form.
Bamboo can be processed to create a silky, soft yarn that drapes well. Bamboo is highly absorbent with antimicrobial qualities maintained through multiple washings, and takes bright dyes well. Bamboo fiber is manufactured by two different methods. “Natural” bamboo is mechanically processed much like flax or hemp, by crushing the stalks and removing or combing the fibers. Bamboo can also be processed in the same manner as rayon (viscose) fiber, with chemicals and equipment used to make synthetic fibers. Manufacturers are now required to label these “rayon like” yarns with terminology such as “bamboo sourced viscose” rather than “natural” bamboo. The chemical processing of bamboo fibers destroys the antimicrobial properties.
Manufacturers are continuing to produce yarns from new sources such as soy, kapok, pearls, and milk (casein), adding to the variety of yarns available in the market place.
MANUFACTURED CELLULOSE BASED FIBERS
RAYON Rayon is not a true synthetic; it is regenerated cellulose manufactured by the same processes as for synthetic fibers. It is the oldest manufactured fiber developed around 1910 in the United States. It was developed as artificial silk, a cheaper substitute for real silk. Today, two types of rayon are produced; viscose rayon and modal. Modal is a modified version of viscose that has greater strength than viscose rayon when wet.
Rayon is a fiber with a soft hand, and drapes better than cotton. It dyes better than cotton because of its higher absorbency, but has low strength when wet. Historically, rayon was notorious for shrinking and stretching. Manufacturers over the years have developed better processing techniques to alleviate these problems. 100% rayon tape or ribbon yarns are available and rayon/cotton blends are common. Rayon in a blend adds absorbency, softness, and drape. Take caution when laundering and pay attention to the labels, as rayon is generally weaker when wet and may shrink.
There are a variety of synthetics manufactured today, but only a few are used in hand knitting yarns. All synthetics are manufactured in filament form, and then cut into staple lengths to be spun into hand knitting yarns, resembling the texture of natural fiber yarns.
Amongst knitters there is varied appeal of synthetic yarns. They are generally less expensive and easier to care for. As a rule synthetics absorb very little moisture and can feel hot and clammy. They are prone to pilling and look worn much sooner than natural fibers. Stains may set and are almost impossible to remove. With knitting experience you will notice a characteristic hand of a synthetic. I refer to the hand as “plastic like”. Manufacturers are coming out with quality blends of synthetics and natural fibers that have favorable properties of both fiber types. The following synthetics are most commonly found in hand knitting yarns.
NYLON Nylon is the generic name for one of the fibers found in the group polyamides. It was introduced to the market place just prior to the second World War, as a cheap alternative to silk for producing hosiery.
The major advantage of nylon is its strength. It is one of the strongest textile fibers and is used in blends to reinforce them. A common blend is a small percentage of nylon and wool, as in many sock yarns.
Pilling is a problem because it is so strong; the fibers get tangled and cannot be broken off the surface of the textile. Nylon is also heat sensitive and may lose its shape. Due to the very low moisture regain of nylon, static cling can be a problem.
ACRYLIC The first production of acrylic was around 1950. This fiber began as a replacement for wool because it was less expensive and washable.
The best applications for acrylic are as “novelty” yarns, such as fake fur and other bulky, textured yarns. Acrylic blended with wool has a better hand than 100% acrylic yarn.
Care must be taken when laundering, as it has poor resiliency and will stretch when wet. As with most synthetics acrylic is heat sensitive. A short dryer time is recommended at a low temperature. Do not iron at hot temperatures, as it could melt or lose its shape. Acrylic is also prone to severe pilling and static cling. Definitely save acrylic for beginner and baby projects, and not for complex items that you spend many hours knitting.
POLYESTER Polyester is generally found in combination with other fibers. Polyester has excellent resistance to wrinkling. It also has very good strength. Pilling and static cling are problems, as with most synthetics.
METALLIC FIBERS Metallic threads or yarns are the oldest form of fibers dating back to ancient Persia and Assyria. These early metallic fibers were actually strips or filaments of real gold and silver. Today, metallic fibers are made by laminating rolled foil with plastic film that can be colored and then cut into narrow strips.
Metallic fibers are not strong and are primarily for decorative effects. Hand knitting yarns are commonly blended with a small amount of the metallic fiber, as they increase fabric stiffness. Some newer modifications are softer. Due to the plastic film, they are heat sensitive and caution must be taken when applying heat or cleaning.
Getting to know fibers will help you in choosing the appropriate yarn for your projects.