This method uses organic compounds (chemicals) as washing solvent.Characteristics: the method does not make the fabrics shrunken or deformed, and it is easy for finishing; but it hardly removes water-soluble stains such as sweat ...
Due to requirement on high safety during solvent operation and storage, specialized dry-cleaning equipments are used. This is also the reason why dry-cleaning method can be applied at laundries only.
Besides, dry-cleaning solvent is re-used for many times, it is necessary to consider professional skills of the laundries in order to avoid bad effects to washing process.
Currently, there are 2 types of dry-cleaning solvent which are being used popularly, including: chlorine-based dry-cleaning solvent (PERC) and oil-based dry-cleaning solvent (Hydrocarbon). Despite having the same name of "Dry Cleaning", they are remarkably different. Next section will provide more details on each type.
Chlorine-based dry-cleaning solvent (PERC)
This type of solvent is used popularly at laundries in Hanoi, its full name is Tetrachlorethylene, or PERC.The solvent has special absorption power on oily stains and can remove them easily. However, it may solute other plastic materials which have the same nature such as vinyl plastic or artificial leather items, thus the risk of damaging such clothes is especially high.
Moreover, because its density is higher than water (1.42 times higher), impact force between clothes and dry-cleaning solvent (mechanical force) will be greater than that of laundry cleaning method. This helps to improve cleaning efficiency, but it may also damage or break buttons and decorated items.
In spite of being a relatively effective cleaning method without deforming clothes, PERC has been prohibited in many countries because it may cause bad effects to human health and environment, it will be replaced by a safer and more preeminent solvent soon.
Evaluation (3-level scale):
Cleanliness level (hardly removing water-soluble stains)
Easy finishing level (preserving original form of the clothes)
Risk level of damage (damaging some types of materials, attached items)
Oil-based dry-cleaning solvent (Hydrocarbon)
This dry-cleaning method uses organic compound named hydrocarbon as the solvent.This solvent does not have strong absorption power on oily stains like PERC and its stain removing capacity is also weaker. However, with auxiliary dry-cleaning chemicals, cleaning efficiency of the method has been improved considerably...
In addition, due to weaker absorption power on synthetic plastic materials, vinyl plastic and artificial leather clothes (which cannot be dry-cleaned by PERC) can be cleaned safety by this hydrocarbon solvent.
Density of hydrocarbon solvent is only 0.8, this makes the cleaning method safe for decorated items of the clothes.
Evaluation (3-level scale):
Cleanliness level (improved by auxiliary dry-cleaning chemicals)
Easy level finishing (preserving original form of the clothes)
Risk level of damage