Richard (Dick) Muhlethaler, a thermoforming pioneer who founded Arrem Plastics Inc. in 1945, has died at the age of 108, six days shy of his 109th birthday.
Born in Newark, N.J., in 1911, Muhlethaler earned a mechanical engineering degree from the Newark College of Engineering. He started Arrem Plastics in Chicago, and later relocated to Addison, Ill.
He was a charter member of the Chicago Section of the Society of Plastics Engineers. He received awards from SPE and the Society of the Plastics Industry Inc., now the Plastics Industry Association, honoring him for innovation, design and execution. The awards included several recognitions for the top part of the year.
In 1959, Arrem began pressure forming to replicate mold detail on the formed part, making Muhlethaler a pioneer in that process. In the 1960s the company began forming parts with undercuts for the lighting industry, using advanced forming and tooling techniques. The parts with undercuts were often used to conceal the metal lighting fixture so that only the formed diffuser was visible, creating a "free floating" effect.
Muhlethaler held two U.S. patents. One was for an all-plastic lighting fixture enclosure that used undercuts to create an integral latching system to seal the enclosure. The second patent was for a two-sided, pressure-formed lens with an optically effective prism on the inside and outside of the lens without using matched metal dies or "coining" the plastic material.
Arrem later used undercuts combined with the pressure forming of etched textures from the tool surface and tight radii (of less than 1/16 of an inch) to form parts that rivaled the appearance of injection molded parts, but with lower tooling costs and shorter lead times. These parts were widely used for high-end applications such as enclosures for medical test equipment — helping to usher a big market for heavy-gauge thermoforming.
In 2002, Profile Plastics Corp., another heavy-gauge thermoformer in Lake Bluff, Ill., bought Arrem Plastics.
According to people who knew him, Muhlethaler allowed every Arrem employee a level of self-determination to decide the best court of action for the long-term good of the company, without interference from him. He shunned the limelight, they said.
An avid golfer, he hit a hole-in-one when he was 83 years old.