ask the labs

The Perils of PAL Pens

Susan P. Tarrant

Progressive addition lenses can present a special challenge at the dispensing table. The markings on the lenses help ensure that the fit is the best, visually, for the patient. But, getting those markings off can be work.

Here, we tackle the topic of markings, and look at how the evolution of the lens generation process has affected it.

LOSE THE ACETONE

Q Do progressive lens manufacturers ever use water-soluble ink for the progressive markings? If not, is there a process to make the removal procedure easier? Having to use All Off, acetone, or alcohol is a real pain. In most cases, the lenses have to be cleaned and re-dotted, so using ink that comes off easier would make things go much smoother.

A ECPs, lens manufacturers, and laboratories have all struggled through the years dealing with progressive lens markings. As any good optician will tell you, these markings are an essential part of the dispensing process, as they help to ensure the best fit possible. The markings are essential for mapping out the lenses in a universally understood way.

That said, the challenge is creating the perfect consistency within ink markings that allow a lab to conduct its fabrication process without removing the markings, yet still be relatively easy to remove at dispensing. This requires quite a balance, and it ultimately presents itself as a very frustrating situation at the dispensing table.

■ EVOLUTION. As the mix of products being consumed continues to evolve, we are seeing more and more Rx's leave the laboratory with “aftermarket” markings. The reason for this is that the digital (or freeform) and anti-reflective processes are such that we are required to remove these markings in order to complete our fabrication process.
■ REMOVAL HELP. Whether the concern is removing manufacturers' ink markings, or those reapplied by your lab, we have found that a product called Delta Ink Remover works in almost all situations, and is also very cost effective.
■ WARNING! We would strongly suggest that acetone never be used in any situations as the chemical is simply too caustic, and while it may not always cause an immediate breakdown, it can often cause damage and premature failure at later dates. My advice for eyecare professionals is to work in tandem with their laboratories in finding the best solutions to these problems.

—Jeff Szymanski, vice president,
Toledo Optical Laboratory,
Toledo, Ohio

If you have a question you'd like to have answered in Ask the Labs, send it to Susan P. Tarrant. Email: Susan.Tarrant@WoltersKluwer.com. An archive of past Ask the Labs columns can be found on the Eyecare Business website at eyecarebusiness.com.