Many launderers view spa towels as bad news and might even try to avoid taking them.
They tend to cling to the odours of the essential oils used in a great many spa products, leading to customer accusations of poor washing and even ‘no washing’!
Even worse are the rancid odours that develop as the towels age, sometimes after only 20 washes or so. Several might then start to exhibit holes and tears when towels used in guest rooms that came from the same original batch are still strong and smelling sweet!
There are now solutions to each of these problems, drawn from the latest technology and sometimes coupled with innovative machine design.
This month we look at the craft skills involved in producing spa towels that consistently look and smell fresh and clean, lasting for a full life of up to 200 wash and use cycles.
The source of the problem
It is the essential oils in spa products that give the user of the spa some of the fragrances that contribute to the guest experience. These are highly refined and plant-based.
They have to be taken into solution in both the pre-wash and main wash by an emulsifying agent. This contains amphoteric molecules, one end of which takes the molecule into solution in water and the other dissolves in oil.
The emulsifying agent is designed to sequester (lock onto) the essential oils and solubilise them safely into the wash liquor and so eventually down the drain. The problem until recently is that standard laundry emulsifying agents targeted either food fats or mineral oils but did not work very well on spa oils.
The consequence of this poor performance was a washed towel that looked clean, but smelt strongly of spa fragrances as soon as it was unloaded from the tumble dryer.
The attraction of the cotton loops in the towel was greater than the power of the emulsifier to remove them. The heat of drying on the unremoved oils starts to degrade them, producing products with bigger molecules that cling more tightly to the textile and can start to give it a yellow or grey tinge.
Production of these degradation products continues during the next few cycles and starts to give the towel a much more rancid stench, which is stronger than the residual fragrance of the spa products.
Among the products produced in the dryer are acid radicals, which attack and rot the cotton itself.
After about 20 wash and use cycles (it varies according to the spa oils and the dryer conditions), the cotton becomes so weak that it tears easily and goes into holes, either in use or when being unloaded from the washer.
The link between spa oils and laundry fires
Any fat, oil or grease (FOG) which is not washed off completely from a textile represents a potential fire risk.
Any FOG will tend to oxidise in the dryer, triggered by the chemical reaction between the oxygen in the air and the heat in the drying air stream. This type of reaction tends to be exothermic (it gives off more heat), causing the local temperature of the textile to rise.
Occasionally this causes spontaneous combustion in the dryer (if the local temperature on a contaminated fabric rises even briefly to the auto-ignition point). The temperature at which ignition occurs is of course much lower on cotton contaminated with residual oil than it is on clean fabric.
Dryer fires are not that uncommon (some sources quote a few thousand reported to the UK Home Office each year).
Far more serious are fires which break out in the clean textiles stored in the finished goods area. If there is a pile of warm spa towels that have not been washed sufficiently thoroughly and which are still contaminated with traces of oil, then the warmth is sometimes enough to continue the chemical oxidation reaction between the oil and the oxygen.
This reaction starts in the hot airstream in the dryer itself (creating the horrible smells), but if it continues in the warm pile in the finished goods area there is nowhere for the heat to go and the temperature can rise exponentially.
The heat this generates increases the temperature at the centre of the pile and after a considerable time (often four to five hours, sometimes even longer) the entire pile will burst into flames and fling blazing cotton fabric across the laundry.
This is believed to be the prime cause behind the mysterious laundry fires which start without any warning in the middle of the night and result in total loss because there is no one on the premises to attend to them or to sound the alarm.
In the UK there are one or two large laundries burnt down each year with an average loss of some £5m or more! The risk in hotels and restaurants can be even more serious, especially if there are people sleeping on floors above the laundry.
Modern emulsifying agents are designed to target one or more groups of oils, ranging from mineral oils, through food fats right down to essential oils used in spas.
Premium emulsifying agents will tackle the entire range of fats, oils and greases. These have been developed from extensive research work by the leading suppliers and the best will handle spa oils just as efficiently as they do engineers’ oils and greases.
It is also possible to improve the residual odours on spa towels by an extra dosage of detergent, but this is far more hit and miss, difficult to control and out of date. Use of the correct emulsifier is the way forward.
Some launderers and a few machine suppliers believe the solution is to use washer-extractors for all spa towels because the necessary chemistry cannot be targeted at the batch of spa towels alone in a tunnel washer.
Certainly, this represents logical thinking, although at least one leading chemicals’ supplier is now reported to have cracked the problem in tunnels.
There is one washer extractor that stands out from the crowd – the Xeros-enabled design. This innovative and ingenious system uses XOrbsTM to replace at least half of the water in the washer cage, reducing, by about one half, the cost of processing spa towels in terms of heat energy, water and chemicals (both detergent and emulsifier).
The unique attraction of the XOrb (which is oleophilic – ‘oil-attracting’) is believed to help the final removal of the last traces of spa oil contamination from the surface of the towel.
This, coupled with the reduction in chemical, water and energy costs, makes a strong justification for using these machines in every laundry charged with decontaminating spa towels. There is an equally strong reason for having at least one Xeros-powered machine in every spa itself.
Achieving complete removal of spa oil contamination thus has a significant implication for textile replacement costs, because it eliminates the rotting which would otherwise occur, and which leads to short towel life. It also has a strong influence on the perceived quality of the wash.
Towels that still have a fragrance of essential oils after washing give the customer ammunition for complaint. If this fragrance degenerates into a rancid stench, then the complaints get much stronger and more difficult to explain! If the ultimate outcome of inadequate washing leads to a laundry fire, then there is a serious consequence on laundry finances.
So how does the poor launderer control this key aspect of product quality when they have a busy laundry to run? There is one key critical control point that is not that difficult to monitor, at the exit from the tumble dryer.
A warm spa towel that has been correctly washed smells clean and fresh to the human nose, which is an extremely sensitive organ. If management, supervisors and operatives are trained to sniff every spa towel batch as it comes out of the dryer, they will quickly, reliably and inexpensively detect any batch which could pose future problems.
In laundries that have experienced spontaneous combustion of poorly washed batches, this check has been enthusiastically embraced. It now needs to be copied in those laundries which recognise the potential hazard, see the risk of it occurring and want to avoid it!
Washing spa towels is not a task for the enthusiastic amateur.
It calls for a professional launderer’s craft skill and knowledge, combined with the correct chemistry and the right machinery. But success carries its own rewards and is a useful marketing tool in its own right.
If a laundry can wash spa towels successfully, then it has demonstrated an ability to tackle what has become known as a difficult classification.
It provides an entrée into any hotel with a spa and into any standalone spa in the country. The skills are not that difficult, the chemistry now exists and there are even washers containing Xeros technologies that could have been designed and built with this problem in mind!