by Laureen Belleville
Certain critical environments, from pharmaceutical, biotechnology and medical devices to semiconductor and aerospace equipment, require wet cleaning. The most widely used wipers in highly critical areas (ISO Class 5 [Class 100] and cleaner) are those made with fabrics knitted from filament polyester or nylon. These fabrics are cut into wipers and then laundered to reduce contamination.
Design criteria for wipers include determining the proper wiper type for your application, the solvent or disinfectant required to do the job, the proper size and put-up, the packaging system that is compatible with both the wiper and the solvent and the proper saturation level.
A main benefit of the presaturated wiper is that solvent use is optimized without the safety problems associated with solvent storage, use and disposal. For solvents the 70 percent isopropyl alcohol and 30 percent deionized water blend ratio is considered the most effective for a wide variety of cleaning applications. This blend also provides efficient drying without leaving a residue. Generally the solvents are filtered to remove all particles to a level of 0.2 micron and some meet SEMI specifications for ions and contaminants. Wipers with a ratio of 96 percent isopropyl alcohol and 4 percent deionized water, for example, are suited to cleaning fiber optics, magnetic tape heads, CRTs and disks. These applications require a cleaning agent that reacts and evaporates quickly.
Manufacturers of presaturated wipers.
An alternative to toxic and flammable solvent-based cleaners such as acetone and isopropyl alcohol is intended for spot cleaning and removes grease, adhesives and photo-resist stains from most surfaces. Filtered to 0.1 micron, it is geared to semiconductor, electronics and aerospace operations.
Manufacturers of presaturated wipers (con’t.)
Some vendors, offer point-of-use saturation products. Blend strength of the solvent and wiper saturation level are determined by the user.
By changing the weight, construction and fiber type vendors can produce wipers to meet many different needs.
Wiper products from High-Tech Conversions (left) and the AlphaSat 100% IPA CleanPak by (Texwipe).
Distributors of presaturated wipers
- Benchmark Products Inc.; Highwood, IL; Ph: (847) 433-3500
- Hal Sharpe Associates Inc.; Chico, CA; Ph: (530) 899-1555
- Lym-Tech Scientific; Chicopee, MA; Ph: (800) 628-8606
- Ultrapure Technology; Suwanee, GA; Ph: (770) 932-0309
This article was prepared with assistance from Kevin Leak, vice president, Jeff Rhoades, marketing manager, and Eliena Tipler, marketing manager, at VWR Scientific Products in West Chester, PA.