and Fabric Characteristics
Some basic information about fibers and fabric specifications is essential for evaluating and comparing available materials. Here are some essentials, but you might want to purchase a copy of Fiber Facts for a reference text that has more detailed information. It is available through the Cornell Cooperative Extension System online store (www.cce.cornell.edu/store/customer/home). Another very good source of fiber and fabric information is Fabric Link, which promotes itself as "The Educational Resource for Fabrics, Apparel, Home Furnishings, and Care", at www.fabriclink.com/University.html
Fiber content refers to the raw material making up the yarns and fabric. It can be natural, such as cotton, wool, linen, alpaca, and other specialty fibers; man-made from natural plant products, such as rayon, acetate, and lyocell; or synthetic from petroleum products, such as polyester, nylon, acrylic, olefin, or spandex. Fiber content is a major contributor to the appearance, comfort, durability, costs, and care characteristics of fabrics. Fibers present in percentages above 1% must be labeled by percentage as a required component of your product's label.
There are three main categories of fabric construction: nonwoven, woven, and knitted.
Fabrics can be constructed directly from intertwined fibers, such as felt or modern non-woven fabrics. Fabrics can also be formed from yarns that are then woven or knitted into fabrics.
Yarns can be formed from continuous filaments, either naturally, in the case of silk, or extruded from machinery, in the case of man-made fibers. Filament fibers are often very smooth, although texture can be imparted to the fiber to change that.
Yarns can also be spun from short fibers, such as with cotton, wool, and linen. Cut lengths of man-made fibers can be used to create a softer texture or to blend with natural fibers.
Very fine yarns such as microfiber yarns, can be created from filament yarns. Yarn diameter, twist, and texture will all affect the characteristics of fabrics made from them.
There are many methods to weave or knit yarns into fabrics. Woven fabrics have sets of yarns interlaced at right angles to each other. The interlacings can vary considerably to create patterns, nap, or textures. Knitted fabrics are made by intermeshing loops of yarn. There are several types of knit with different appearance and characteristics, as well. Fabric construction will influence the aesthetic, functional, and cost qualities of materials and is the third characteristic important to your choice.
Many fabrics are characterized and sold based on weight. Think about the variation in your T-shirts. Some are lightweight (2-4 oz. per yard) while others are heavier (6-8 oz.per yard). The yarn diameter and the number of yarns per inch of knit or weave determine the fabric weight. One measurement system used for yarn weight in some fibers is denier, equal to the mass in grams of 9 kilometers of that yarn. As the denier becomes larger, it describes a heavier yarn. A more detailed explanation is available at www.sizes.com/units/yarn_numbers.htm.
Fabrics are referred to by weight in ounces per yard. A shirt or blouse will typically use a lighter weight fabric than pants or a skirt. The weight of the fabric you should choose depends on whether your product's value is in function, durability, or price.
Color and Print
It is important to understand the various ways that fabrics can be dyed and printed. These determine different care requirements and expected colorfastness. Dyes can be pigments put into synthetic fibers before they are formed. Fibers, yarns, fabrics, or finished garments can be immersed in dye solution. Dye chemisty varies to accommodate fiber content and the desired color effect. Fabrics vary in colorfastness, depending on the chemistry of the particular dye or pigment, the fiber type, and how well the colorant is absorbed into the fabric. If color maintenance under particular conditions is desired, it is a good idea to check with the fabric manufacturer or converter to see specifications for dye fastness, or to send fabrics to a lab for testing.
Fabric can also be colored by printing. Print paste can be applied with rollers, blocks, flat screens, or rotary screens, or transferred from paper to fabric with application of heat.
One innovative computer-assisted printing method is called digital printing. It adds value by
- printing one-of-a-kind images onto completed stock, such as T-shirts
- printing images onto pattern parts before construction to accommodate engineered patterns for one-of-a-kind styles.
Digital printing advances the mass customization production method by allowing single-item or small quantity printing on stock fabric.
Fabrics have a wide array of finishes, such as a flame retardant required for children's sleepwear, a waterproofer, or a stain preventer such as Teflon. In addition to imparting special properties to fabrics, some of these may require special care. This information should be provided by or requested from materials vendors before purchase.
1. What three pieces of textile information are required by law on the labels of apparel and home furnishing products.
2. When you ask for a knitted material, are you indicating fiber content or fabric construction?
3. What performance characteristics do knits have that make them desirable for clothing?
4. At what stage can color be added by dyeing: fiber, yarn, or fabric?