SMT stencil cleaning is a high-risk, high-reward process, demanding the most from the fluids, wipes and tools. Proper cleaning results in perfect PCBs. Incorrect or inadequate cleaning produces expensive junk. To achieve the highest levels of stencil cleaning, especially on BGA stencils, and even more especially on stencil designs with densely packed circuitry, the best cleaners produce the highest yields.
While MicroCare does not offer simple housekeeping or hygenic cleaners, there are instances in which surface cleaning rises to be a critical application. This might be in a clean room for a medical device manufacturer or perhaps in an SMT assembly area at a company making circuit boards.
MicroCare products are used on armored vehicles, airborne platforms and on fire-and-control systems. MicroCare cleaning fluids are used in the field, at repair depots, and by the original manufacturers, even for cleaning radioactive devices.
Mass transit systems have very challenging cleaning environments. Subways, light rail systems, airport people-movers and city busses have a wide variety of cleaning problems: from simple grime and graffiti to cleaning complex electronics, removing protective coatings and refurbishing expensive traction motors.
Silicone is a remarkable and flexible polymer. It is generally used in making gaskets, insulation, protective coatings and specialty tools. It is affordably priced, easy to mix and handle and offers numerous characteristics that can be very handy.
Removing glues, adhesives and binders often is a problem in manufacturing and repair processes. There is a wide variety of chemistries found in glues, from polyvinyl acetate in white glues to cyanoacrylates (“Super glue”), silicone adhesives, complex polymers found in hot glues, polyurethane glues and epoxies. Matching the adhesive to a solvent can be a tricky balancing act.
Inks can be very challenging to clean because most are formulated to be permanent and very durable. Inks are formulated from different fluids and chemistries; while many are alcohol-based there are many other carriers that might be used. For example, epoxy inks are virtually indestructible. Finding a solvent that is safe for people and still has the cleaning power to remove these versatile materials can be problematic.
Removing water droplets and preventing/removing water spots is a specialized niche in the world of precision cleaning. In many manufacturing environments, aqueous cleaning is used for gross, general cleaning. The excess water then is removed with powerful air knives and/or heat.
Today’s electronic components run hotter, are smaller and more complex than ever before. With the pervasive deployment of BGAs and microBGAs, MCM devices and even denser semiconductor packages, clearances are so tight that aqueous systems simply cannot clean these components without higher spray pressures, extra cleaning agents and longer, more vigorous drying cycles.
The metal finishing industry is a diverse sector. Almost any company that is plating or anodizing would fit this category, or companies making circuit board components, costume jewelry, chrome metal furniture frames, automotive trim and household fixtures like doorknobs.
Rosin-based fluxes and solder pastes are a sub-set of general electronics cleaning. The precision cleaning and defluxing of traditional RMA, RA and OA fluxes is seeing a resurgence in the marketplace as no-clean fluxes have proven to not be the panacea they were originally proclaimed.
No-clean fluxes and solder pastes are another sub-set of PCB cleaning that requires special consideration. Most no-clean fluxes are more difficult to clean than rosin-based fluxes and pastes. These contaminates require a cleaner formulated with aggressive solvency, and possibly using inorganic fluids to fully remove any white residues.
Lead-free fluxes and solder pastes are another problem area in PCB cleaning. Most lead-free fluxes are more difficult to clean because they require higher temperatures to reflow. These contaminates are prone to white residue problems and require a cleaner formulated with aggressive solvency, and possibly using inorganic fluids to fully remove these residues.