Denier Measurements: Definition of Clothing Apparel Search
Denier provides a scale for the heaviness (largely related to thickness) of fibers in a fabric. The higher the denier, the thicker the fiber. The denier value is defined as the mass in grams per 9000 meters of yarn. Contrary to some claims, the unit is not "mostly obsolete", but still finds much use in the fiber industry.
Denier or den (abbreviated D), a unit of measure for the linear mass density of fibers, is the mass in grams per 9000 meters of the fiber. The denier is based on a natural reference: a single strand of silk is approximately one denier; a 9000-meter strand of silk weighs about one gram. The term denier comes from the French denier, a coin of small value. Applied to yarn, a denier was held to be equal in weight to 1⁄24 ounce (1.2 g). Microdenier describes filaments that weigh less than 1 g per 9000 m.
There is a difference between filament and total measurements in deniers. Both are defined as above; but the first relates to a single filament of fiber (commonly called denier per filament (DPF)), whereas the second relates to a yarn.
Broader terms, such as fine may be applied, either because the overall yarn is fine or because fibers within this yarn are thin. A 75-denier yarn is considered fine even if it contains only a few fibers, such as thirty 2.5-denier fibers; but a heavier yarn, such as 150 denier, is considered fine only if its fibers are individually as thin as one denier.
The following relationship applies to straight, uniform filaments:
1 denier = 1 g / 9000 m = 0.11 mg/m
In practice, measuring 9000 meters is both time-consuming and unrealistic. Generally a sample of 900 meters is weighed, and the result is multiplied by ten to obtain the denier weight.
In tights and pantyhose, the linear density of yarn used in the manufacturing process determines the opacity of the article in the following categories of commerce: ultra sheer (below 10 denier), sheer (10 to 30 denier), semi-opaque (30 to 40 denier), opaque (40 to 70 denier) and thick opaque (70 denier or higher).
For single fibers, instead of weighing, a machine called a vibroscope is used. A known length of the fiber (usually 20 mm) is set to vibrate, and its fundamental frequency measured, allowing the calculation of the mass and thus the (linear density).
Learn about fiber & fabric units of measure.