Cotton fabrics have been around since ancient times and while their basic properties should be second nature to cleaners, surprisingly I have even found launderers that were unaware of the ironing temperature required for cotton or the temperature delivered by their steam heated hand irons. So, let’s take a look at some important facts relating to cotton that cleaners should know.
- Cotton gains strength in washing.
- Attracts free moisture in drycleaning so good classification is important for whites
- Requires a finishing temperature of up to 200C.
- Responds well to finishing and particularly from a slightly damp condition.
- Cotton dyes are not always fast to spotting chemicals – deep dyed shades in particular.
- Black oil can be difficult to remove from cotton.
Cotton fabrics generally respond well to drycleaning or water based processes; but dry or wet, dyes cannot be relied upon to be fast to spotting chemicals, therefore pre-spotting with kit chemicals is not recommended. When it comes to finishing, cleaners should be aware that at the maximum steam pressure (70 psi) common to dry/wetcleaning boilers, a maximum theoretical ironing temperature of no more than 110C can be achieved (see also LCN June 2024). Realistically, in the working environment, this means that the actual finishing temperature using a steam heated steam iron is most unlikely to be much above 100 deg. C ! – totally inadequate for finishing most cotton or linen garments.
Linen
Very similar to cotton, over the years, linen has developed something of a reputation in drycleaning for being a potential problem fabric. This, in my view, is quite undeserved and provided that the clearer is aware of the following, linen is not difficult to clean.
- 30% stronger than cotton, linen gains an extra 10% when wet.
- Dyes can be prone to colour loss from spotting chemicals.
- Pre-spotting with kit chemicals should be avoided.
- Requires a finishing temperature of up to 200C
- Creases and wrinkles very easily.
Because of the risk of colour loss, particularly on deep dyed shades, do not pre-spot with kit chemicals but general prespotting with specialist products designed for sensitive items is normally safe.
Linen can be difficult to finish to a very good standard and even when new the standard of finish is, shall we say, often less than perfect. It is also the case that some customers when purchasing a garment are completely unaware of linens propensity for creasing and somehow expect things to change when they have it cleaned. Because of this it is a good idea to establish the customers expectations during reception. Additional care in finishing is required to avoid glazing seams and it can be beneficial to mist the garment very lightly with water and cover with a cloth prior to ironing.
Viscose rayon
This was the original manmade fibre, it was first commercially manufactured in the UK by Courtaulds in 1905. Produced from wood pulp, at the time it was referred to as artificial silk; with about half the tensile strength of silk, viscose has very poor wet strength.
- Viscose loses 50% strength when wet.
- When spotting on the wetside tamp gently with a soft brush – do not use a spatula.
- In terms of stain removal the dye fastness of viscose is considered to be better cotton or linen.
- Classify delicate viscose garments with silk and / or delicate items
- When drycleaned/washed use a reduced/ gentle or handwash cycle to reduce mechanical action.
As pressing is a low temperature process, steam ironing at 150C, if possible on the reverse of the fabric over a cloth to prevent shine is likely to produce the best result. The answer to the steam iron issue is to install either a professional or a domestic electric steam iron.
Finally, a reminder on stain removal. It is entirely the cleaners responsibility to ensure that the spotting chemicals selected to treat a stain do not affect the colour. Pre-spotting is always the most risky option as the cleaner is normally unaware there is a problem until a damaged garment is taken from the machine.
