may 22, 2011

Washing and wetcleaning

Richard Neale explains why drycleaners may need to use water-based cleaning methods.

Water is a powerful solvent and can be a useful tool for professional drycleaners. It will dissolve polar compounds – substances that split into ions such as sugar and salt, battery acid, oven cleaner, baby bottle sterilising fluid and most food and drink stains, with the exception of oil-based marks. This is why washing is used domestically.

Unfortunately, washing can lead to problems of shrinkage. This includes noticeable shrinkage on cottons and felting shrinkage of wool suits and angora sweaters. It can also lead to crack-creasing on most acetates and velvets, with the associated shrinkage. Drycleaning overcomes these problems by “washing” in solvents, which is why the drycleaning industry has developed and prospered.

Wetcleaning was developed to clean many types of “non-washable” items. This specialist process uses low temperature to minimise wash shrinkage of cottons and low mechanical action to avoid felting shrinkage of wool and cashmere and crack-creasing of acetate and viscose. The trick is to let the water do the work. The chemicals used in wetcleaning are designed to protect the work as much as to remove the dirt.

Just as a well-trained drycleaner can produce superb results with drycleaning, so a well-trained wet-cleaner can produce equally good results with wetcleaning in many cases but the results on staining are not the same. Oily marks come out better in drycleaning, sweaty armpits and soup spills are better wetcleaned.

Washing and wetcleaning can be extremely useful processes for the drycleaner when rescuing damaged items or when improving the drycleaning outcome.