An ancient process still used to keep us warm and comfy, fabric napping and similar treatments also deserve their place in the field of technical textiles.
What do wool pile, flannel, polar knit, suedette and fleece have in common? They have all been napped.
Napping is a mechanical surface treatment that makes the fabric thick, soft and cuddly. Napping machines, also known as wooling or raising machines, are fitted with revolving cylinders covered with metal points which raise the surface fibres. For fine fabrics such as suitings, or for short fibres such as cotton, emery cloth is used instead of metal points. This is the technique used to obtain sueding.
Napping – fabric “FRISBI/N” by INSETA
After the napping process, the fabric becomes more or less woolly. This is the fleece stage. To ensure equal thickness and give the fabric a more elegant look, it must then be put through a shearing machine. The final step consists of brushing the surface to give it lustre and set the lay of the pile. Depending on the method used, the result is a wool pile if the nap is upright, otherwise it may be flattened for a smoother effect by using a process known as decating.
Napping – fabric “USSAMELO/N” by INSETA
It can take up to 28 operations, excluding dyeing, to treat fragile fibres such as angora, alpaca or baby wools, because napping is too rough a process and could damage them. They require gentle brushing, with rest periods between brushes to allow the fabric to “relax.”
Napping – fabric “DALLAS” by Manifattura Del Prato
Napping not only gives a fuller handle and handsome look, it also improves the performance of the fabric. It increases the adiathermic qualities thanks to the air trapped between the fibres, and it reduces contact points with the skin, which makes for better breathability and evaporation of perspiration. This explains why napping is so widely used in sports apparel, especially for polar knits and similar items.
WORDS FROM HISTORY
Woollens : it can be a another word for napping. Which doesn’t mean that wool is the only fabric that can be napped. The explanation comes from the Indo-European root of the word wool, which also means “pulling,” the same technique used for removing and processing fleece.
Thistle or teasel top: In the old days, thistle tops were used to card wool. They have since been replaced by metal points, and the thistle plant has grown rare, though it is thought to have valuable medicinal properties. The word “carding” comes from the French word for thistle: “cardère.”
Arles merino: with its 20-micron diameter, it is the only fine wool to be found in France. It arrived in Arles in the early 19th century and remains a highly-prized, 100% French material. Jules Tournier is one of the main manufacturers using this wool.
WORDS FROM EXPERTS
Jules Tournier, a unique company with a fully integrated wool carding activity. “We use special yarns and weaves for our napped fabrics. That is one of our manufacturing secrets. We control the entire production chain and have an archive dating back 150 years that allows us to precisely reproduce any product.”
Lanificio Becagli combines tradition and innovation in its sport fashion products, taking advantage of the technical qualities of napped fabrics. Since pilling is the bane of polar knits and other napped or sueded fabrics using microfibers, this Italian manufacturer has developed its own anti-pilling treatment.