Assignment 4: Textile Structures

Woven Fabrics

Woven fabrics are created by crossing yarns at right angles to each other.  This creates a structure that after washing and finishing (setting) is dimensionally relatively stable horizontally and vertically. Depending on the structure of the weave and whether the yarns used are springy, some stretch can be introduced into wovens. Wovens are naturally somewhat more stretchy on the bias (diagonal), a characteristic that has been used to great advantage in dress design since it was pioneered by designer Madeleine Vionnet in the 1930s.

Here are some examples of woven fabrics.  All photos by the author.

 Andean tapestry.

 Brocade for upholstery.

Herringbone twill.  Wool.  Coat weight.

Carved velvet.  Cotton.

 Taffeta.

 Tartan 2 X 2 twill.  Wool.  Kilt weight.

 Terry cloth.  Cotton.

Warp faced weave.  Wool blend.  Light suit weight.

Window screen.  Fibreglass.

The type of fibre, construction of the yarns (ply, spin, etc.), weight of yarns, weave pattern and density, and finishing techniques such as fulling or glazing all affect the way a woven fabric will behave in terms of handling, stretch, drape, breathability, heat retention and even cleaning requirements or restrictions.  These considerations influence which fabrics can be used for which purposes.  A heavy, tight weave such as 16 oz. cotton duck is suitable for applications where the fabric's rigidity is useful, such as with luggage, hammocks, utility upholstery and even shoes and artwork.  A fine, light fabric such as cotton lawn is suited to highly detailed and refined garment construction techniques that demonstrate the skill of the designer and seamstress.  The finer the fabric, the more it will be able to follow the complex contours of the human body, but this must be balanced with practicality and durability as finer fabrics are more prone to tearing and wearing through.

In addition to the usual fibres, high tech fibres are being used in woven materials to address specific challenges. For example, fibreglass and carbon fibre have many familiar uses, silver is used for electromagnetic sheilding, Nomex is used for fire resistance, Kevlar for puncture resistance and Twaron for impact resistance.

Knits

Knit fabrics are constructed with interlocking loops. Crochet fabrics are considered knits.  The yarn within a knit remains much more mobile than the yarn in a woven and this creates a fabric that is both looser and stretchier than is possible with weaving. It is not possible to knit a fabric that is as tight as the tightest wovens. Knits are generally much more drapey than wovens, with lighter knits being the drapiest.  Whereas wovens fray when cut, many knits tend to unravel or run, or the edges roll up dramatically.  This necessitates special seam finishes such as serging or taping.

Here are some examples of knit fabrics.  All photos by the author.

 Stockinette and 2 X 2 rib.  Wool.  Lightly felted.

 Knit mesh.  Nylon.

 Fair Isle.  Wool acrylic blend.

 1 X 1 rib.  Cotton.

Athletic jersey.  Polyester.

Polar fleece.  Recycled polyethylene terephthalate (PET).

Knits are ideally suited to clothing, especially where stretch and comfort are desired.  Because of their looser structure they trap more air than wovens made of similar yarns and this makes them more breathable and, paradoxically, more insulating except under the windiest conditions.  Modern fibre technologies have improved the shape retention (memory) of knits, but many still require some care in laundering to retain their desired shape and texture.

Felts

Felts are constructed of interlocking fibres rather than yarns.  In the case of animal hair or wool, friction is used to cause the keratin scales on the hairs to snag and tangle on each other and ratchet up to form a mat. Heat can help the scales to open up, so steam or hot water are often used. Dry felting is accomplished without heat with barbed needles that catch the hairs and drag them against each other. Where plant or synthetic fibre is used adhesives or heat are usually used to help join the fibres together.  Felts are non-fraying, thick, warm and not stretchy.  Other characteristics such as durability, ability to hold a sewn seam or adhesives, deformation under stress, and resistance to friction depend on the fibres and felting techniques used.  A felt made from 70% wool and 30% acrylic retains the best of the characteristics of wool felt while gaining improved dimensional stability and opacity from the acrylic. 

Woven or knit fabrics made of animal hair or wool can be felted as well, but these fabrics often retain some of the characteristics or the original fabric and are usually still considered under their original categories.

Here are some examples of felt fabrics.  All photos by the author.

 Wet felted.  Wool.

Machine felted (white ground and red trim). Wool. Hungarian crewelwork motif in wool.

Wet and needle felted.  Wool.

Machine felted.  Cotton.

Whereas the most familiar use of felt for many people is in crafts, felts serve a great many other purposes. Next to leather and waxed cotton, a dense felt is the most wind-proof natural material available for clothing. The synthetic felt used for making decorations is inexpensive, thin, easy to cut and work with. Fibre artists use wool, mohair, angora, camel and other animal fibres because they felt readily, take dyes beautifully and have various textures and shine. The felt used to line winter boots must be up to 0.5 cm thick, sturdy enough to keep its shape and not wear out.  Medium weight felt may be used in table silencers to protect the surface from heat damage and to quieten the meal; it is also used in upholstery and quilting. Felt up to 1.5 cm thick is used for yurts.  Felt is used in vehicles, industrial machinery and even geotextiles.  For these last purposes it is engineered to exacting specifications.

Rolled and Pressed

Synthetic roll goods can be made by extruding liquid plastic and rolling it flat as it cools, or they can be spun and bonded with heat and pressure. They can be so thin that their thickness is measured in mils (1 mil = 0.0254 mm). They can be imprinted with a texture. Some are bonded to woven or knit fabrics for durability and comfort such as in the case of faux leather. Common uses for these materials which can also be made of wovens include shower curtains, table cloths, dust covers for appliances, barbecue covers, banners, bags and labels.

When choosing these "fabrics" consideration must be given to construction techniques.  Some cannot be sewn; some cannot be glued; some cannot be heat sealed.  Some cannot have stress points such as grommets or buttons.  

Some roll goods are very high tech, designed to solve specific technical problems, for example: Gore-tex provides water proofing with breathability; Smart-fab provides low cost non-fraying, non-shedding disposable fabric for sanitary environments; Mylar reflects radiant heat while being practically weightless and is used to insulate winter wear and oven mitts; Tyvek is wind-proof, water-resistant and practically impossible to tear, used in construction, clothing labels and hazmat suits. 

Here are some examples of rolled or pressed fabrics.  All photos by the author.

 Vinyl.  Embossed.

 Vinyl.  Seams sewn and heat-sealed.

Smart-fab.

Choosing Fabrics

When selecting fabrics for any garment or home decor project there are three aspects to consider other than cost: aesthetics, such as drape and handling qualities; functionality, such as durability, waterproofing or strength; and comfort, such as stretch and softness.  For example, a hat could be made of woven, knit, felt or roll goods, but the purpose of the hat and the needs of the wearer will affect the choice. When there are several possible candidates for a project, bearing these three categories can help in making a decision.  

Useful Resources

Andie. (2014). American felt and craft - the blog.  Retrieved from
http://americanfeltandcraft.wordpress.com/about/

Bryk, N. (2014). How Products are Made. Retrieved from
http://www.madehow.com/Volume-7/Felt.html

Dupont. (2014). Apparel and textiles. Retrieved from
http://www.dupont.com/products-and-services/apparel-textiles.html

Smart-Fab. (n.d.). Retrieved from
http://www.smartfab.com/Homepage

Textile Glossary. (2014). Warwich Mills, Inc. Retrieved from
http://www.warwickmills.com/Roll-Goods.aspx