Patents Behind
the PolycoldTM Process

Patents that Inspired...

Mixed Refrigerants and Polycold™ History...

The history of mixed-refrigerant technology, to our knowledge, starts in 1936 when W.J. Podbielniak of Chicago obtained a U.S. Patent. His single-compressor low-temperature refrigeration system contained a mixture of hydrocarbons. Although Freons were not then in common use, he knew that they would work in his system. His invention was notable considering he developed it over 70 years ago. Earlier, in the 1920s, work done on gas separation laid a foundation for mixed refrigerant systems. The same physical principles apply.

In the fall of 1968 Dale Missimer contacted friends at DuPont to learn more about mixed-refrigerant systems. He had heard of low-temperature cooling based upon mixtures. This was shortly after selling his company, Missimer Inc., to Gulf and Western Industries. A DuPont engineer sent a copy of a 1965 U.S. Patent issued to Andrija Fuderer of Jugoslavia. Correspondence led to a license from Dr. Fuderer to Conrad-Missimer (a Division of Gulf and Western Industries).

Later he discovered that A.P. Kleemenko, a Russian, had published in 1958, a technical paper describing the mixed-refrigerant system he had developed. Also some European inventors had created cryogenic mixed-refrigerant systems. Their application included large systems (more than 1,000 horsepower) for liquefying natural gas. However, he could not find any organization designing or making small systems.

In 1970 Dale Missimer and others at Conrad-Missimer, began two years of research and development efforts. The goal was to produce reliable low-temperature refrigerators using the Fuderer low-temperature refrigeration process. He made and sold several models with the Conrad-Missimer label.

Later a Cold Trap Chiller model was developed called the PCT-015. This new unit was primarily focused at the vacuum systems market for use in water vapor cryo-pumping applications. A field once dominated with the use of liquid nitrogen. This also marked the beginning of the Polycold trade name.

Sometime around the mid-1970's, Dale Missimer left Gulf and Western Industries, and formed two new companies. One was called Marin Tek Inc., which was going to serve as the manufacturing aspect. This was to be jointly owned with two other partners, Rod Sutliff and David Edwards. The other company would be known as Polycold Systems International. And would concentrate on the sales of products that Marin Tek was going to build. As part of leaving Gulf and Western, Dale had also negotiated a licensing deal in which he obtained exclusive rights to use the Polycold name, and the low-temperature refrigeration technology he had helped develop while in their employ.

Some Trivia... The word Poly is actually a word used to describe more than one or "many". So Polycold really translates as "Many-Cold" which represents the mixed (or many) refrigerants used in a typical Polycold unit that are responsible for it getting cold.

Patents that Defined Polycold