Wipes

Solvent compatibility is another factor to consider when choosing a wipe. If the wipe is to be used with a solvent in the cleaning application, then the wipe must be selected with the solvent in mind. Solvent retention and absorbency may also be required. The wipe must the able to absorb a given solvent and retain the solvent within the fabric of the wipe for a sufficient amount of time, without premature release of the solvent. Knitted polyester and nylon wipes have the highest compatibility with a wide range of organic solvents and weak acids. Coventry Poly-Wipes and Cleanroom Chamois have good absorbency, excellent durability when cleaning rough surfaces, and low ionic and organic residue contamination. The polyester/cellulose blended Chemtronics Controlwipes and Coventry Econowipes have excellent resistance to solvents and weak acids, good durability when cleaning rough, abrasive surfaces, high particle entrapment and low particle and ionic contamination.  They are an economical choice for general cleaning and spill clean-up.

Any wipe will produce particulates depending on the amount of abrasion it receives in use, so abrasion resistance should be considered. Wipes usually release the most particulates from their edges, so using a sealed-edge wipe will greatly reduce the particulate burden.  Heat cutting is a common method of creating a sealed edge. A hot knife cuts the edge and simultaneously fuses all the loose ends on the wipe, as in the Coventry Poly-Wipes. The texture of the wipe should also be considered when critical or sensitive surfaces are involved in the application. Some wipes can abrade some critical coated optical surfaces and should therefore be avoided in such applications. Chemtronics Twillwipes (C900) are knit cotton wipers that are also very good on abrassive surfaces.

Chemtronics general purpose wipes are meant to be used for wiping and in non-critical or controlled environments. By cleanroom standards, Chemtronics general purpose wipes would be acceptable in Class 10,000 cleanrooms or in “controlled environments”. Chemtronics ControlWipes (C910) and Coventry Econowipes (6709) have a non-woven blend of polyester and cellulose, with the best properties of each. The cellulose gives it good solvency and strong cleaning strength, and polyester it gives it good wet strength and then a high degree of cleanliness. Because of absorbency, strength, and lower cost, TechClean Wipers are commonly used in electronic assembly on SMT stencils for removing solder pastes and adhesives.

Cleanroom wipes used for critical applications are almost always knitted synthetic fibers. Knitted polyester fabric, like used for Coventry Poly-Wipes (part #6209), is the most popular wipe material for cleanrooms. Knitted polyester is made clean, contaminants can easily be removed from knitted polyester in a cleanroom laundry, and polyester is relatively inexpensive. Non-woven wipes do not offer the advantage of ease in cleaning as their composition causes them to disintegrate in a cleanroom washing machine or cleanroom drier.