Hydrocarbon solvent continues to be an issue of fascination with drycleaners, judging from the high turn-out at the recent meeting of the Guild of Cleaners and Launderers.
Many members had come along to listen to Alex Reid’s Bob Ball-entyne give his views on the topic.
Kicking off his presentation with the subject of garment labelling and, more specifically, the use of the F-label, Mr Ballentyne said in Germany this label covered the use of hydrocarbon solvent for a wash cycle of a maximum of 20 minutes, with drying at a cage exit temperature of 60°C.
He was confident that this definition would also be valid for the UK.
Mr Ballentyne then compared the properties of hydrocarbon solvent with 113 and perc.
Hydrocarbon has a solvency value similar to 113, a density less than water (which could reduce the mechanical action) and a low vapour pressure. He pointed out that the solvent supplied by different petroleum suppliers varied in its properties.
It was noticeable that there was a 14% difference between the lowest and highest solvency value (KBV).
A serious problem with the practical use of hydrocarbon is that of flammability. Mr Ballentyne explored the different methods used by various machine manufacturers to combat the problem from nitrogen blanketing to vacuum and solvent cooling.
He also discussed whether a machine should have distillation or rely on absorbtion filter powders. In the latter case, he pointed out, it could be beneficial to have all the solvent distilled once or twice a year.
Whichever type of machine is chosen, the wash cycle should ideally be 10-12 minutes, and during spotting it was essential to flush out the chemicals used, Mr Ballentyne said.
