Machine Embroidery Thread: Rayon or Polyester?

Traditionally, there are two major choices for machine embroidery: rayon or polyester machine embroidery thread. Both threads are synthetic: rayon created from plant-based products and polyester from petroleum-based products. Rayon was created in mid-nineteen century as an inexpensive substitute for silk; whereas polyester has only been around for about the past 60 years. So which do you choose for your project? If you already have a decided preference, rayon or polyester, that, then, is the absolute best choice for you. However, for those of you who would like to use both, the following discussion of threads should help you choose the thread best suited to your project.

The Major Difference between Rayon and Polyester

There are two major differences between rayon and polyester machine embroidery thread: rayon is more rigid with a subtly glossier sheen, and polyester is stronger with a bit more stretch. When polyester thread was in its infancy, the sheen of rayon was vastly superior, but modern technology has narrowed the gap until now it is difficult to note the difference. Indeed, many people mix the two.

When to Choose Rayon

For delicate fabrics, such as dressy baby clothes, fine underwear, or textiles requiring dry cleaning, rayon is an excellent choice. These fabrics will be handled with care, without harsh chemical, thus preserving the embroidered designs. For lacey designs, rayon is an excellent choice because the thread is spread less densely over the design. Rayon is more heat resistant than polyester because it is made of plant based materials whereas polyester is petroleum based. Rayon should be used at lower embroidery speeds as it will break much more easily than polyester at high speeds.

When to Choose Polyester

Modern polyester threads are well-suited to most machine embroidery, and practically required by the high speed commercial embroidery machines. Polyester is very strong, durable, and color fast. You can bleach polyester, and it will retain its bright color; whereas rayon will fade. Therefore, polyester is the better choice for projects that will receive heavy usage and projects that will be washed often.

A Final Thought on Rayon and Polyester

Whichever thread you ultimately decide to use, choose a high quality thread like ThreadArt threads. If you are unsure which thread you will prefer then buy a spool or two of both rayon and polyester to test out. A good quality thread has few thread breaks and embroiders evenly with no skips or knots. A good quality thread makes you happy with the end results.