Flying high: Success with airline textiles

At many airports, and certainly at most of those hosting an airline’s base, there is a local laundry which specialises in processing airline textiles. This demands rapid turnaround, high quality stain and soil removal and attention to key details. This can be a very profitable business, with a year-round flow of similar items from clients whose customer experience is supported by the quality skills of the launderer.

In practice, every laundry could learn from the agility and forward thinking of the airline launderer, so this month we take a look at the skills required and how these can be turned to very profitable use in any laundry.

Shrinkage

All textiles have the potential shrink in laundering and drycleaning! When supplying textile items that need to fit either the wearer or the cabin seat, for example, they need to be delivered slightly oversize to accommodate the relaxation shrinkage. This arises not from any fault on the part of the cleaning company’s processes but is caused by the unavoidable release of normal manufacturing strains in the various textiles used. Any item could lose 2-3% in size in drycleaning, simply because of the lubricating effect of the drycleaning solvent on the yarns, at the molecular level. A seat cover designed for drycleaning must therefore take this into account in manufacture. Otherwise, after cleaning, it might be a very tight fit on the seat frame, or even display gaping seams. In developing a good relationship with an airline customer, a cleaner or launderer could offer test cleaning to enable the precise identification of the degree of oversize required. ­

Wash shrinkage results from normal relaxation plus the effect of water and temperature on the yarns in the textile. For example, cotton and other cellulosic fibres swell in warm water, pulling the fabric in as they dry, and the resultant wash shrinkage is not fully reversed in drying and finishing. Wash shrinkage is normally higher than relaxation shrinkage and an item could easily lose 5- 7% in each direction. Even the use of more expensive, pre-shrunk cotton cloth might reduce this only to say 3%. For this reason, it is essential for an airline to check the wash shrinkage before ordering and ensure that the manufacturing measurements reflect this correctly. This is particularly important for areas likely to encounter frequent and/or heavy staining, such as seat covers, napkins and crew kitchen items. Laundries must look at the stains and decide whether they should be removed by a good laundering process, rather than drycleaning. ­

Felting shrinkage is caused by excessive mechanical action in the presence of moisture on items made from a hair fibre. This is one reason why a garment fabric containing a percentage of wool would normally be classified for drycleaning (enabling tight control of moisture content in the cleaning fluid). It is also the reason why any item containing wool must be totally dry before going into the drycleaning machine.

The effect of excessive moisture on a hair fibre such as wool is to cause the scales on the individual fibres to rise, creating the appearance of a barbed spear. This can be pushed in one direction with the mechanical action in the cleaning process, but this cannot then be reversed when the action changes. The result is to produce a sightly thicker, stiffer fabric with a matted surface, very little elasticity and considerable shrinkage. The damaged articles cannot be rectified, but if the fault arises then an airing or drying stage before drycleaning will prevent it occurring in the future. ­

Crease-cracking of natural and artificial silk fabrics (such as viscose and acetate) produces tiny tight creases, accompanied by significant shrinkage. It is caused by the same combination of mechanical action in the presence of moisture which causes felting of hair fibres and could ruin silk or viscose scarves worn by some cabin crew. Because airline textiles frequently require the removal of body-based soiling and staining, which is best removed with plenty of moisture in the system, any fabric which displays crease-cracking in test cleaning or laundering should be fully test washed and the results reviewed by both the airline and the laundry before deciding on their introduction. ­

Thermal shrinkage is a real problem with modacrylic fabrics, which are prized for their insulation properties and for their inherent flame retardancy, but which are temperature sensitive. Use of perchloroethylene in the drycleaning of airline textiles gives high cleaning power, but the final drying temperature must be reduced into the range 40 – 45C for these fabrics, to avoid the excessive shrinkage which would otherwise occur. The safe range for drying modacrylic blankets and duvets after laundering varies with different types of modacrylic fabric construction.

Stain and soil removal

Airlines quite rightly demand very good stain and soil removal from their circulating stocks, not least because an airline passenger cannot be expected to accept a stained, dirty seat, with old residual soiling and staining still visible on it. Most of the staining encountered in the airline cabin is either from human body fluids (which are mainly protein based) or from food (producing a combination of protein and vegetable dye stains). These types of stains are far better removed by a skilfully designed laundering process, rather than by drycleaning. This makes a powerful argument, wherever possible, for designing airline textiles to be washed. Modern laundry processes can be designed to operate at low temperature and still achieve superb soil and stain removal, along with disinfection to the latest healthcare standards.

Historically, some airlines and manufacturers have not considered the benefits of regular cleansing on their textiles and simply passed the problem over to their cleaning and laundering contractor. There has then been little option but to dryclean the non-washable items, necessitating individual stain pretreatment, a much greater tendency to long-term greying and the unwelcome appearance of hidden stain residues. In stark contrast, airlines and manufacturers which have paid proper attention to correct design for multiple cleansing have enjoyed bright and fresh stainfree textiles, with seat covers which fit correctly throughout their service life.

There are still some stains which merit individual attention, including iron oxide (rust) residues from old blood stains. These require special chemical treatments, either by pre-spotting for small stains or by a dedicated chemical process in a washer extractor for more extensive marking. Repeated washing or repeated drycleaning will not work and are a waste of time. Only a good professional cleaner can recover these.

Odours

Odours can occur on some airline textiles, especially those that have been drycleaned or incorrectly laundered. They are usually the result of incomplete removal of staining and soiling. This is another powerful reason for designing textiles for both multiple use and multiple laundering. Protein residues, in particular, are prone to bacterial infection, and it is these which can give rise to the most unpleasant odours. Professional laundering processes which include low temperature disinfection are the best way to avoid them.

Washing and cleaning

Airline textiles can be washed in either a washer extractor or in a tunnel washer. In a washer extractor they will need a main wash which runs for at least 8 – 10 minutes. In a tunnel washer they need a total process time of usually at least 30 minutes. These processes should be reviewed regularly in conjunction with your detergent supplier. A good detergent system is essential, with proven capabilities at low temperature (in order to get the best life out of complex seat covers , for example). The chemical mix will probably need good low temperature emulsification properties to remove not only food oils and fats, but also essential oils used in skin care products that might be used by passengers. Vegetable dyes from red wine, beetroot, blackcurrant, tea and coffee will require low-temperature oxidation to decolour them effectively and permanently.

It is important to stick to the load factors stipulated by machine makers, because airline textiles need the correct lift and drop action to dislodge old stains, for example on seat covers (which might be washed only at quite extended intervals). Where time is at a premium, it is important to have sufficient machine capacity for immediate processing. Meeting return deadlines by over-loading or by shortening processing time are not sensible options.

Drying

It is generally essential, in order to minimise drying or ironing time, to optimise moisture extraction after washing. For a washer extractor process, this means selecting the fastest spin speed which the textiles are able to withstand without creating irremovable creasing. In a tunnel washer, it is vital to maximise the time at pressure in the membrane press, so that maximum pressure is imparted on the textiles without damaging them or causing the need for additional finishing. Conditioning (or partial drying in the tumbler) is dependent on the textile construction and the finishing to come. At the ironer, use every lane for tray cloths and table napkins, to get the batch through quickly, ensuring they do not dry out (and so causing a poor finish). For tips on ironer tuning for good quality with high productivity, see LCN Material Solutions for July-August 2022.

Conclusion

So, what makes airline textiles such a specialised classification? It is probably the combination of very high quality and very high immediately available capacity which the market demands. Meeting the airlines’ deadlines with stain- and soil-free textiles, every time, every day calls for the best professional laundering and cleaning skills, sound, hands-on management and the latest technical knowledge. The most successful launderers have recognised the need to build a working relationship with the airline customers, so that they design and buy textile items which enable consistent, fast and very high-quality processing. This is one area of the market where price should definitely come second to customer service! ­