Denier - Art or Science?

by Geraden

In the UK and Europe, hosiery packaging almost invariably gives a denier value – or an equivalent value in the continental decitex (dtex) measure. This is not the case in the USA, where you will find it hard to get any details about denier.

European hosiery consumers set a lot of store by denier, using the value as a proxy for a measure of weight or opacity, whereas Americans rely more on descriptive words such as sheer, day-sheer, semi-opaque and opaque. So who is right?

On the face of it the European system seems more precise and scientific, while the US descriptive words appear to be more subjective. However, the reality is a little more complicated than that.

One of the most obvious questions about any hosiery is whether it is sheer or opaque. In the US the answer to this question alone will determine whether the legwear is to be classed as pantyhose or tights. Pantyhose are sheer, tights are opaque - simple! Well, no, it is not quite so simple as that, and maybe that is part of the reason we Brits insist on calling both sheers and opaques tights. Opacity is of course related to the density of the fabric, and is dependent on many factors. The weight, composition and construction of the yarn, the type of knit and (to some extent) the dye colour are the main ones.

The science

Technically the definition of denier is the weight in grammes of 9,000 metres of yarn.

The denier was an old French silver penny coin. The term denier was originally used in the French silk industry, and passed over into use for artificial fibres. Thus 9,000 metres of 15 denier silk or nylon weighs 15 g. In British terms one denier is 8 1/5 grains, where 480 grains = 1oz = 28.375g.) So that is the weight sorted out! What about the thickness?

A human hair is typically 40 thou (100μ). A single filament 15 denier nylon yarn has a thickness of 1.7 thou (4.25μ). But hosiery is not made from single filament yarn any more. Yarns made from filaments of less than 1 denier are known as microfibre yarns. The filaments that comprise the yarn may be in the order of 0.5 den, though filaments of 0.2 den are not unknown. This is about one two-thousandth of an inch or less than 1.5μ.

When nylon yarns were first produced, they were simple, single filament yarns, and there was a close correlation between the denier of the yarn and the thickness of the knitted fabric. Hosiery yarns are now coiled, multi-filament, multi-fibre (typically nylon and elastane) and multi-layer (sheathed). The use of denier in any scientific sense would be far to comlpicated for marketing purposes. Yet British and European consumers are reluctant to give up the denier as a measure of hosiery weight and thickness.  

The art

All this means that the construction of the yarn is more important than the strict denier in determining thickness of the product. So where denier values are stated, if you read hosiery packet carefully, you will see that the value is often described not as 'denier' but as 'denier appearance'. This is especially true in Britain where the Trades Descriptions Act is in force.

So in fact the European system of denier appearance ratings is no more scientific than the narrative descriptions of thickness common on the other side of the Atlantic. To answer the question in the title, denier is more of an art than a science. Having said that, it is still a useful guide, though being subjective, there can be wide variations in interpretation.

It is often said that ultra sheer is 10 den and less, sheer is 15 denier, day sheer is 20 denier, semi opaque is 30-40 denier and opaque is anything above 40 denier.

But even granted that denier is an art rather than an science, denier values do not correlate with the narrative descriptions in this way. This is because those descriptions relate to the sheerness or opacity of tights, and denier is still a measure of thickness rather than opacity. The assumption that tights of 30 denier and above are no longer sheer is not correct. Take Activskin A 569s. These are sheer support tights, but they are 70 denier. The highest denier sheer tights that I have come across, incredibly, are the Solidea Venere support tights from Italy: this range consists of sheer tights in 30, 70, 100, and (incredibly) 140 denier! Mention of these gives me an excuse to post a link to a rather nice commercial for these tights on Google Video.

The last two pictures are both of sheer tights packets, but one is 5 denier appearance and the other is 140 denier. I am not saying there is no diference between them, simply that both are described as sheer!

And that is just what the manufacturers say. Quite often when reviewing tights, I am amazed at variations in the denier ratings. I will give a few random examples to show what I mean.

• The Vogue Harmony tights that I reviewed here recently were very similar to Falke Seidenglatt. The Harmony are rated 30 denier, the Seidenglatt are 15.
• Recently I bought a couple of pairs of Wolfords. The Sheer 15 denier seemed sheerer than the Magic Touch 12 denier.
• Activskin 2019s are rated 110 denier but look and feel more like 30 denier.
• Falke Shelina are rated 12 denier but look more like 8 denier.
• In Max Mara the Microfibra Opaques are rated 50 den but look more like 60 den; the Velato are rated 15 but are more like 10.

If that has not convinced you that the whole thing is so imprecise that it has to be taken with a large pinch of salt, nothing will.

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tags: denier  sheer  opaque  appearance  

links: technorati