Q&A: Keeping clean

While cleaning is the core of MicroCare’s technology, it also offers lubricants designed to impart a better ‘feel’ to medical devices with sliding or pivoting designs. MicroCare VP Mike Jones takes a look at some of the changes in cleaning technology that might offer unexpected options to medical device designers.

MPN: What technical innovations in precision cleaning might be spilling over into the world of medical plastics?

MJ: Many of the solvents used in manufacturing are older technologies, bringing with them significant environmental, health and safety concerns. But in today's world there are new, safe, proven alternatives that eliminate those hazards. For example, one company working with medical plastics was able to transition from a solvent that was a major global warmer — a chemical with an atmospheric life span measured in thousands of years — to something far less harmful. When it did this, it also lowered its production costs by more than $500,000 annually. 

MPN: Everybody knows that solvents are good for cleaning. Are you suggesting there are other specific capabilities that might be utilised?

MJ: Absolutely. In fact these technologies have a number of highly useful applications. They can be used to clean oils, grease and particulate from plastic parts; that’s the easy applications. But they also can be used to deposit PTFE and silicone lubricant coatings on parts and remove water without spotting. Solvents also can temporarily swell plastic parts, such as silicone tubing, to make strong, tight, leak proof friction fittings over barbed couplings. Importantly, most solvents offer non-pyrogenic cleaning, which is very helpful in the medical world. 

MPN: For medical plastics most of the cleaning that is performed is usually done with water.  Are you trying to challenge that concept?

MJ: There is a place for water cleaning — it's safe, consistent, and the equipment used in the process is well-understood. But in many parts of the world, water is becoming very scarce, and electrical costs also are rising. One of the main contributors to global warming is the burning of fossil fuels to generate electricity; water cleaning uses vast quantities of electrical power. So these trends speak against water-cleaning. Additionally, as parts become more complex and cleaning standards climb, the ability of water cleaning systems to achieve ever-higher performance is limited by the water molecule itself. Water cleaning works on high-volume, simple shapes but on complex shapes residues can be a problem, as well as rinsing and bacterial growth. Solvent cleaning addresses all those worries and usually lowers the cost-per-part-cleaned.

MPN: Is there room in the cleaning world for additive manufacturing (3D-printing)?

MJ: Absolutely. One of our favourite solvent products is one that actually attacks the surface of the plastic parts produced in the 3D printing process. The result is a plastic part with a smoother, glossy surface finish, like a finely polished metal part. ‘Solvent smoothing’ is a process MicroCare Medical has pioneered with today's ozone-safe solvents.

MPN: The medical field is dominated by regulatory complexities; would using solvents add another layer to this?

MJ: Today's regulatory environment is very complex. California and Europe are leading the way with new regulations that are forcing reformulations. The new Globally Harmonised (safety) Standards are supposed to make the regulations more consistent around the world, but almost every country and market is trying to make the standards less consistent. For example, in Europe the big emphasis is on REACH, not GHS. Nonetheless, a quality vendor would be well-informed on these trends and policies and help companies navigate the regulatory playing field. In short, no, switching from old-style cleaning to modern solvent cleaning should not create a regulatory minefield.

MPN: How do the new choices measure up in terms of price and performance?

MJ: Generally, they compare favourably. Modern solvent technology is very safe for the environment, for people and for the budget. One medical customer with who I am familiar discovered that switching from water-based to solvent-based cleaning systems reduced their cleaning costs by 86%. Part of the savings stem from the minimal solvent usage in todays' tight cleaning systems, and also the improved cleaning performance of modern products. Solvent cleaning also enables new designs and technologies to be used that simply could not be implemented with older-style cleaners and lubricants.