Manufacturer · Fashion & Home Accessories
Cotton or silk thread – cotton is matte, affordable and withstands high temperatures, so it is the practical choice for garments made from cotton and linen. Silk is finer, stronger and elastic, with a natural lustre, and is preferred for silk and wool fabrics, hand stitching, basting and hand-worked buttonholes in bespoke tailoring.
The two natural fibres in brief
Cotton is a plant cellulose fibre of limited length. To produce a smooth sewing thread, cotton is spun from long fibres, mercerised and gassed. Silk is a protein fibre that the silkworm spins as a continuous filament hundreds of metres long. That is why silk thread is naturally smooth, free of fuzz and has a characteristic lustre.
Cotton or silk thread – a comparison
| Property | Cotton thread | Silk thread |
|---|---|---|
| Look | matte or slight satin sheen (mercerised) | natural deep lustre |
| Strength at the same thickness | medium | high |
| Elasticity | low | good |
| Lint | low to medium | practically none |
| Ironing | high temperature | medium temperature |
| Marks under iron pressure | may leave an imprint through the fabric | leaves almost no imprint |
| Washing | tolerates high temperatures | delicate wash |
| Cost | affordable | considerably higher |
When to choose cotton thread
Cotton is the logical choice for everyday and series sewing of garments made from plant fibres:
- shirts, blouses, dresses and trousers made from cotton and linen;
- home textiles that are washed at high temperatures;
- garments that will be dyed after sewing with dyes for cellulose;
- patchwork, quilting and wadded items;
- production where the cost of thread matters.
Cotton thread is available in a wide range of thicknesses and colours and is readily available on cones for industrial machines. See the options in the cotton threads category.
When to choose silk thread
Silk is a specialist material. It is used where its properties make a visible difference:
- Silk fabrics – the thread is the same fibre, it is fine and does not weigh down the delicate fabric.
- Bespoke wool suits and coats – silk “sinks” into the fabric and the stitching looks invisible.
- Basting (temporary stitches) – silk thread leaves no imprint after pressing and pulls out easily.
- Hand-worked buttonholes – a heavier silk thread (cordonnet) gives raised, lustrous and strong buttonholes.
- Sewing on buttons by hand on high-end garments.
- Hand embroidery, where the lustre is part of the effect.
Silk thread is labelled according to different systems, and thicknesses from different manufacturers do not always match. So for a first order it is wise to compare a sample with the fabric and needle you work with. For machine seams on silk, a fine needle with a slim point is used and the stitch length is reduced so that the seam lies flat. Silk slides easily, so the upper tension often needs to be tightened slightly compared with cotton.
Basting: why tailors prefer silk
In bespoke tailoring, the parts are first joined with large temporary stitches. The garment is then fitted, adjusted and pressed. Cotton thread can leave an imprint on wool and silk when pressed – a mark that is difficult to steam out. Silk thread is thinner and smoother, leaves no such mark and pulls out easily without catching the fibres of the fabric. In series production, basting is replaced by fusing and templates, so the question hardly arises there.
Buttonholes with silk thread
Hand-worked buttonholes are a hallmark of high-quality tailoring. They use a heavier silk thread, often with a gimp (cord) underneath that gives relief. Silk is smooth enough to form dense stitches without fraying and keeps its lustre for years. Cotton can also be used, but the buttonholes look more matte and wear faster at the edge. For machine buttonholes in series production, polyester thread is used.
Alternatives to silk
Because of its cost, silk is rarely used in series-produced clothing. If you want lustre and smoothness but not the price of silk, there are compromise options:
- mercerised cotton – shinier and smoother than standard cotton;
- continuous filament polyester – smooth, strong and lustrous, suitable for synthetics;
- viscose embroidery threads – with a bright lustre, but weaker when wet.
For machine seams on garments, polyester from the sewing threads range is the closest substitute for silk in strength and elasticity.
Care and storage
Both materials should be stored in a dark, dry place. Sunlight fades the colour and weakens the fibres, and moisture leads to mould in cotton. Silk is sensitive to strong alkaline detergents and chlorine – garments with silk seams are washed gently. Cotton seams tolerate more intensive washing, as long as the fabric allows it.
How to choose in three questions
- What is the fabric made of? Plant fibres – cotton. Silk or fine wool – silk or fine polyester.
- Hand or machine work? For hand stitching, basting and buttonholes, silk has the advantage. For machine series sewing – cotton or polyester.
- What are the budget and the volume? For runs of hundreds of pieces, cotton and polyester are the sensible choice.
Threads for clothing from Polkom
Polkom is a manufacturer of accessories for fashion, furniture, footwear and bags, based in Sofia and delivering across the EU. We offer cotton and polyester threads in a wide range of colours, together with buttons, zips and labels. If you are not sure which thread is right for your fabric, send an inquiry via Contact – we will help you choose and send a sample.
