Tech Talk Blog

We’ve all been touched by the recent earthquake destruction in Haiti.  And our team is now seeing a renewed interest in surface treatments that can help building materials (like cement) resist seismic activity and sudden impact.

By adding specially treated polyethylene fibers to concrete mixtures, contractors are able to enhance the strength and durability of preformed structures.  With plasma treatment, our team can select the optimum gas chemistry and operating condition to improve the bond strength and interface toughness of ethylene fibers.  Treated fibers have a significantly improved bond strength compared to virgin, non-treated fibers.  With our plasma process, we can enhance the structural integrity of fiber cement mixtures used in buildings, bridges, and other superstructures.

Our team is designing a lens that must withstand military extremes such as salt spray, fog, humidity and temperature.  The coating must be abrasion-resistant and anti-reflective – what is the best treatment?

This is a great question — and a multi-step process. Assuming your lens is a polymer lens like polycarbonate or CR-39, currently there is no single surface treatment for both anti-abrasion and anti-reflective (AR) properties.  Instead, one would apply the anti-abrasion coating first, followed by the AR process, which is done in a vacuum for a uniform and consistent result.

Your abrasion-resistant coating options include:

A)    Polyurethane  – This usually is the most economical coating, which is applied by either sprayed or dip method. This is a popular treatment for end user ophthalmics, but also has the least durability and longevity.

B)    DLC (Diamond-like coating) – An extremely hard, durable coating, that is relatively expensive, but most effective for high-end users.  DLC ensures high-performance and impact-resistance as the resulting surface is very close to the hardness of diamond.

Our team can help you explore your best solution.

What is the best process for removing silicone oil from a catheter made of Pebax® tubing prior to a bonding operation?  Would you use plasma or corona?

Your question is one that we are seeing more frequently. And the short answer is that it all depends on the amount of oil.

If you can see a significant oil collection, then you need to wash the tubing in an ultrasonic bath with an emulsifier. Then, you may simply wipe the tubing with an alcohol wipe to remove any excess. It really depends on the level of contamination. Generally speaking, I’ve found that catheters have a superficial level of oil.

If the amount of oil is superficial, plasma can carry away the excess oil via a specific oxygen treatment. We do not advise corona treatment for this application, since it can make the silicone hydrophilic and give a false impression of being clean. Plasma is a more elegant solution and will “superclean” the surface to promote better adhesion.  Learn how we recently solved this challenge.

Welcome to the Surface Treatment / Modification Blog.

This Blog will attempt to discuss and inform about anything and everything related to…drum roll please…surface treatment and separate fact from fantasy.

The subject of surface treatment can be difficult to explore. Some techniques are closely held secrets while other procedures are spelled out on the page of a magazine. So, it can be difficult to know what cleaning or surface treatment technique is appropriate for a specific application. In many cases, a perfectly good surface treatment technique is applied to the wrong application, and then the technique is given a “bum rap”; There are many times I have heard…”plasma doesn’t work!” or ” nothing beats my sandpaper and acetone trick.” Well, plasma can work and there is something better and simpler than acetone and sandpaper.

If you have already heard enough and would like help increasing yield, adding value, or developing new products, please go to the TriStar Plastics Corp. web site to initiate your project. Or simply Ask The Experts your questions right away!

So, without further delay…lets blog about Surface treatment.