The wet wiping is an important cleaning process removing contaminants generally invisible to the naked eye. To ensure efficient cleaning, the solvent dampened wipers must be able to absorb a wide range of surface contaminants in the shortest possible time and without themselves distributing further pollution in the form of particles, fibers, ions or microbiological contaminants. 

The solvent such as the IPA (Isopropyl-alchohol) and Ethanol are commonly use together with the De-ionized Water in a pre-define mixture ratio, for example 50%IPA and 50%DI Water.

One to be considered is that the IPA is flammable with high evaporation rate. Hence the safety handling and storage are needed. The chemical should be kept in a tightly closed and sealed container until ready to use. It had to be stored in a chemical cabinet in a cool (not above 23 0C or 73.40F) and ventilated area. Also, the chemical should be keep away from heat and source of ignition, to prevent the fire and explosion hazards.

Below are some of the common issues occurred when using the solvent for wet wiping cleaning process .
a) Personnel hazard â?” the safety handling in mixing, dispensing and storing the solvent.
b) Environmental aspect â?” high VOC (Volatile Organic Compounds) due to the solvent evaporation.
c) Inconsistency of Solvent/DI water mixture concentration â?” dependent to operators
d) Wastage of solvent – Spillage while pouring the solvent
e) Maintenance of chemical bottles – squirt bottle or dispensing bottles
f) Non productivity process â?” pouring cleaning solution onto the wiper or spray it onto the surface of parts being cleaned.
g) Over saturation and non-uniform saturation on wipers will reduce the cleaning efficiency.

So, it is important to have proper education to the cleanroom personnel with regards to the use of solvent chemical in the wet wiping.

The other good alternative is to use the pre-saturated wipers which are available in the market, this would directly resolve most of the issues as discussed above. These readily saturated wipers come in a vacuum-packed, sturdy and recyclable, refillable pail. The pail also comes with easy resealable hinge lid, to keep the wipes moistened and wet all the time.