AATCC 158:2005 pdf download.Dimensional Changes on Drycleaning in Perchloroethylene: Machine Method
6.1 Drycleaning machine. This shall consist of a commercial rotating cage type, totally enclosed machine for use with perchloroethylene. The diameter of the rotating cage shall be not less than 600 mm and not more than 1080 mm. Its depth shall be not less than 300 mm. It shall be fitted with three or four lifters. The speed shall be such as to give a g- factor (see 13.2) between 0.5 and 0.8 for cleaning and between 35 and 120 for ex- traction. The machine shall be equipped with a thermometer for the measurement of the solvent temperature. The machine shall have suitable facilities so that the emulsion can be introduced gradually into the solvent between the inner and outer cages below the level of the sol- vent. The machine may be of the single- unit washer/dryer type or a separate dryer may be used. Both types of dryers shall be equipped with temperature control of either the incoming or the outgoing air during the drying cycle. (Information on solvent recovery is given in 13.3.)
When loaded into the machine, the specimen(s) and the ballast shall be in equilibrium with the standard atmosphere for testing textiles. Equilibrium is deemed to be attained after exposure for 24 h to this atmosphere.
9.1.2 Place the conditioned load in the machine and introduce perchloroethylene containing l g/L of sorbitan mono-oleate so that the liquor ratio, calculated on the volume of solvent in the outer and inner cages, is 0.65 ± 0.5 L for each kg of load (this corresponds to a solvent level of about 30% of the inner cage diameter). Maintain the solvent at 30 ± 3°C (86 ±5°F) throughout the cleaning operation.
.1.3 Prepare an emulsion by mixing 1 part (by volume) of the sorbitan mono- oleate with 3 parts of perchloroethylene and then adding 2 parts of water (with stirring). Start the machine with the filter circuit shut off and slowly (over a period of not less than 2 min and not more than 12 min) add an amount of emulsion cor- responding to 2% of water calculated on the mass of the load, to the machine be- tween the inner and outer cages below the level of the solvent.AATCC 158 pdf download.