Client & Alumni News

RADIUS Toothbrush Success Story

RADIUS invented a two-part toothbrush product line. The components were a head made of transparent plastic and a handle made from either a solid plastic or an electronic handle that delivered the amount of time necessary to brush and a meter to count the number of uses.

Shortly after launching the product line, customers started to return a large number of toothbrushes. The common problem was that the head snapped off at the point of insertion into the handle. Our engineering team immediately assumed that the design of the junction between the two components was poorly engineered and overloading the head component, thus causing failure.

We re-designed the junction, re-built the molds, and returned to production. Within a month or so, we were back again receiving broken toothbrushes in the mail, followed by letters of complaint.

The Ben Franklin Technology Partners associate in our area, Connie Faylor, suggested that we approach Pennsylvania College of Technology and ask for suggestions. An initial meeting produced the idea of a research project to analyze our failures and to make recommendations for the materials. RADIUS and Ben Franklin Technology Partners enthusiastically entered into this project.

After a few months of intensive research, the team at Penn College had taken a large number of our replaceable toothbrush heads, run them through a battery of rigorous tests, and established the cause of the failures. It was not an engineering issue, but a failure of the transparent ABS plastic that we had selected. Toothbrushes are subjected not only to stress from the action of brushing, but also are immersed in toothpaste. The ingredients of toothpaste include peppermint oil (a very potent chemical), bicarbonate of soda, and hydrogen peroxide. All of these chemicals can corrode plastics, in particular when the plastic is already weakened by being transparent.

Having successfully analyzed this complex problem we were now faced with the need to replace the ABS with another material that would not fail. Penn College professors and associates analyzed multiple plastics and came up with a final suggestion – Trogamid nylon from Degussa in Germany. This plastic is extraordinarily resistant to attack from chemicals. Further extensive testing at Penn College proved that it resisted the three main culprits of our failures. RADIUS put this plastic into service immediately. We have not received a broken or snapped-off head ever since. 

Some years on, RADIUS is celebrating great success and, in particular, our Source™ product line, with the infamous replaceable heads, is now our leading product.

Penn College did a terrific job in analyzing and locating the source of failure and in recommending new plastics to replace them.

I recommend them highly.

Kevin Foley
RADIUS Toothbrush