Typically, machine embroidery can enhance a garment's beauty or add a personalized or themed embellishment. Machine embroidery threads are special threads that embroiderers use when creating these embellishments. They can vary from basic cotton to one of the newer threads, such as metallic or light-sensitive thread. Manufacturers technologically formulate machine embroidery thread to withstand the strain of machine embroidery. Often as the thread passes through the embroidery machine's tension disks and the needle, there is considerable strain on the thread.
There are two types of threads: natural fibers and synthetic, or manmade, fibers. Traditional natural fibers include cotton, linen, and wool, but manufacturers are developing new fibers like bamboo viscose threads. The wools may include sheep, rabbit, and other animal fibers. Rayon, nylon, and polyester top the list of synthetic fibers.
Manufacturers use different techniques to create machine embroidery threads. Monofilament thread is a single filament, which manufacturers produce by forcing polymer resins through tiny holes. Spun threads are fibers that machines spin into single threads, and then several of these fibers are spun into thread. Core threads are monofilaments wrapped with spun fibers. Another synthetic specialty thread is filament polyester or nylon that a machine texturizes to create a fuzzy and elastic thread.
Some of the newest machine embroidery thread creations include the innovative special-effect threads. These range from a fuzzy wool and acrylic blend that produces a crewel embroidery effect to synthetics in bright neon colors. Two popular special-effect threads are those that change colors in the sunlight and those that glow in the dark.
Rayon thread often is an embroiderer's favorite choice because it has more sheen and is available in most markets. This type of machine embroidery thread generally resists breaking or unraveling during high-speed stitching. Typically, manufacturers offer rayon embroidery thread in a variety of solid and variegated colors. One newer rayon thread has two or more solid colors twisted during production.
Another popular machine embroidery thread, and one of the most economical ones, is polyester embroidery thread. Being a synthetic monofilament, it is comparable to rayon. It is available in various colors, including variegated ones. Like rayon thread, it is shrink proof and fade resistant. Typically, rayon thread has a slightly superior sheen than polyester thread. Usually polyester thread and rayon thread are interchangeable.
Cotton thread has a softer sheen and is generally available in more thread weights than the synthetic threads. Very fine cotton thread usually is called heirloom quality. These very fine threads often are weaker than heavier threads and tend to break easily. An embroiderer often may overcome this handicap by sewing slower. The average weight — 30- or 50-weight — cotton thread is stronger and more popular with embroiderers.
Many embroiderers enjoy the luxury of silk threads. Silk fibers absorb dyes more vividly than other natural fibers and have a distinguishing sheen. Generally, silk thread sews efficiently without breaking. Like cotton machine embroidery thread, silk is available in a wide range of weights, but most embroiderers use the 30 to 50 weights.
If an embroiderer wants to add sparkle to the design, metallic threads are an excellent choice. The metallic machine embroidery thread has a monofilament core that is wrapped with metal foil. Some manufacturers apply color by affixing a colored polyester film to the foil. The most expensive metallic threads have a coating of rice paper on the core to stop the metal from separating from the core. Generally, cheaper metallic threads tend to separate, snag, and break during the embroidery process.