D/Denier
“D” is short for Denier, a unit of measurement indicating the linear mass density of fibers. It represents the mass of the yarn per 9,000 meters and measures in grams. A higher D value indicates a thicker yarn. Denier is important , no matter polyester fabric or nylon fabric.
For example, 75D is thicker than 50D. In swim trunks, the fabric made of 32D fiber is denser than those made of 25D.
The concept of 1D is based on a natural guideline: a single filament is equal to 1D, and a filament weighing 1 gram over a length of 9,000 meters.
The term “Denier” comes from the French word for a small-denomination coin (1/12 of a sou). In textiles, 1D is equivalent to 1/24 oz.
1 denier = 1 gram / 9000 meters = 0.05 grams / 450 meters (1/20 of above) = 0.111 milligrams / meter
The D value is typically calculated by weighing a sample of 900 meters in length and then multiplying the result by 10. Polyester filaments with a denier of 1D have a diameter of approximately 10 micrometers.
We use the term “Micro-Denier” to describe very fine yarns with a mass per 9000 meters of less than 1 gram.
The fineness of the yarn determines opacity:
- Below 10D = Ultra-transparent
- 10D-30D = Transparent
- 30D-40D = Semi-transparent
- 40D-70D = Opaque
- Above 70D = Extremely opaque
Hence, the higher the denier, the denser the fabric is.
What is Tex
“Tex” refers to the weight of a yarn that is 1000 meters long, measured in grams. Tex is used in Canada and Central Europe, while “Denier” is used in the United States and the United Kingdom.
A more frequently used advanced unit is “Dtex,” which is the abbreviation for decitex. It indicates the weight of a single yarn thread over a length of 10,000 meters.