He explained the different causes of shrinkage and how to allocate the blame for each and went on to consider dye mark-off, stain removal and holes.

He said that investigating the damaged item requires a detective-like mentality, observing and recording without always knowing where the investigation will lead. Then suddenly all becomes clear and the cleaner will be able to recognise the difference between a hole caused by a one-legged seafarer from that produced by the grub of the hungry clothes moth!

Shrinkage in drycleaning

Shrinkage in drycleaning can be caused by one of four ways:

Felting shrinkage is caused to hair fibres (wool, angora, cashmere, mohair) by drycleaning with too much moisture in the system. If just one item is damp, then that will be the only one in the load to shrink; if every hair fibre item shrinks then the problem is probably caused by droplets of water in the solvent, from a leaky still condenser for example.

Relaxation shrinkage affects every type of fabric. It occurs when the drycleaning solvent allows the release of the slight stretch set into the cloth by the fabric maker. The British Standard for curtain fabric allows the cloth maker a relaxation of 3%; manufacturers of fully fashioned clothing usually work to tighter tolerances than this.

Solvent shrinkage affects fabrics containing polypropylene (which commonly occurs in non-woven fabrics made from recovered fibres and produced by “garneting”). Watch out for suite covers made from pure woven polypropylene – these will shrink by over 20% when drycleaned in perchloroethylene

Thermal shrinkage affects acrylic and modacrylic fibres which occur in knitwear and some types of outerwear as well as in curtaining. The outlet air thermostat must be turned down to 50C or below for acrylic and 40C for modacrylic.

Relaxation shrinkage is sometimes reversible by repressing using tension and vacuum. The technique is to pull the lay to size and then to apply vacuum to cool, dry and set the cloth before tension is released. Felting, solvent and thermal shrinkages are all non-reversible.

The manufacturer is usually responsible for relaxation shrinkage, because only the cloth maker is in a position to know how much stretch is set into the cloth. A good garment maker will relax the cloth immediately prior to cutting out, often by light steaming.

If the owner of an item complains of shrinkage then they are probably justified because all fabrics relax in cleaning. Puckering of the main seams is the usual tell-tale sign. The main point to determine accurately is the degree of shrinkage and the cause, so as to pinpoint blame precisely.

Poor colourfastness

Loose dyes cause damage not only to the item from which the colour bleeds or marks off, but also to other items in the load. Poor colourfastness affects a great many garment and household textile ranges and is frequently discovered only when the item is drycleaned.

The source of the loose colour can be determined by examining the pattern of the mark-off and by carrying out simple colour fastness testing at the stain removal table. A small piece of clean cotton cloth is moistened with drycleaning solvent and rubbed firmly over the suspect print or dyed fabric. If the colour is loose it will immediately mark-off onto the test fabric. This test by the cleaner is essential when contemplating cleaning an unlabelled set of curtains for example.

If the bleeder has been classified with a load of pure white goods, then the cleaner must be prepared to defend the classification decision or take the blame. If the bleeder is classified with a load of similar items (all of which are prints on a pale background for example), then the blame will generally lie with the manufacturer. There are British Standards for colourfastness of curtaining in drycleaning to which reference can be made in a dispute.

Poor stain removal

Stains which appear during cleaning usually result in long and acrimonious arguments about who put the stain there. The cleaner tries to explain that the staining occurred in use and has developed in the cleaning machine process, whilst the owner is certain that the item was unmarked when handed in. Often both parties are right. There is a wide variety of staining based on proteins or sugars which dry to leave no visible mark and which are therefore not pre-treated prior to cleaning. They do not dissolve in drycleaning solvent and darken with the warmth in the tumble dry stage, hence the complaint.

They can usually be detected both before and after cleaning using an ultraviolet light. Sugar stains from wine or lemonade will tend to fluoresce white under uv, with a bright white rim from the crystals of sugar. Protein stains, from perspiration or meat juice tend to fluoresce pink. Sugars can be removed with water and steam (and considerable patience if they have caramelised). Proteins need a proprietary protein remover or ammonia, some work with the tamping brush and some persistence.

Looking at holes

Holes are always a source of strong argument because they usually look worse after cleaning than they may have done before. When examining a hole, look for:

Size, shape and location

Colour damage around the hole

The condition of the ends of the damaged yarns at the edge of the hole

Other damage nearby

Acidity or alkalinity of the surrounding fabric

Distortion to the weave or the knit

Cuts from a sharp knife produce a row of neatly severed yarns whereas moth grubs will munch in a semicircle. Acid and alkali damage will usually cause a colour reaction as well as changing the surface pH. Snag damage produces distortion to the surrounding structure. Abrasive wear produces damage to the surrounding surface yarns.