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R-12 Retrofitting: Are we really doing it because DuPont’s patent for Freon® ran out?
by John R. Hess
From May/August 2001 Cool Profit$ Magazine
© 2001 All Rights Reserved

Every week I hear somebody say “this whole R-12 retrofit debacle is happening just because DuPont’s patent on Freon ran out.” Think about that. Assuming it to be true, then for all these years DuPont would have to have been the only company manufacturing and selling R-12 (not!). And then, anticipating that they were going to lose control of the product, they chose to sabotage R-12 by getting the EPA to ban its existence.

Continuing this doomsday scenario, losing their monopoly on the auto refrigerant, they "invented" R-134a and miraculously got it universally accepted by the world as R-12's replacement. And they did this all the while knowing that they would somehow be able continue to monopolize sales of R-134a as well??? Doubtful!

Obviously those concepts are false. Along with DuPont, Atofina Chemicals (formerly Elf Atochem), Ineos Fluor (formerly ICI Klea) and Honeywell (formerly Allied Chemical and Allied-Signal) were all major vendors of R-12, and are today major suppliers of R-134a. The "other three" did not pay royalties to DuPont for their sales of R-12, and will not for R-134a.

Who holds the trademarks and patents for Freon?
We know that the registration for the trademark “Freon” was filed on December 8, 1931 and registered May 10, 1932. It was issued for “Fluorinated Hydrocarbons Used As Refrigerants, Propellants and Fire Extinguishing Preparations,” and was first used in commerce December 1, 1931. The registrant was Kinetic Chemicals, Inc. of Wilmington, Delaware, which became E. I. du Pont De Nemours and Company.

Above top: Chapman & Hall Encyclopedia of Environmental Science says that Kettering’s and Frigidaire’s Patent Number 1,886,339 was the first patent covering CFCs.

However, this author could find no mention of CFCs in its description. In the opinion of the author, Midgley, Henne and McNary’s patent for Heat Transfer (Above lower ) should be the first patent for CFC based refrigeration, refrigerants and air conditioning.

The trademark search was easy and clear. The patent search, however, proved to be more difficult; there is none, at least not under the name Freon. (Thanks are owed to Chris Bede, Webmaster of www.aircondition.com for getting me started in the right direction.) The timeline below is far from the whole story, but for our purposes it is close "enough."

Summary of Refrigeration History
For a quick summary of refrigeration history, here’s a review from Chapman & Hall Encyclopedia of Environmental Science, edited by David E. Alexander and Rhodes W. Fairbridge, pp pp.78-80, Kluwer Academic, Boston, MA, 1999. It’s located on the National Oceanic and Atmospheric Administration website.

“Refrigerators in the late 1800s and early 1900s used the toxic gases, ammonia (NH3), methyl chloride (CH3Cl), and sulfur dioxide (SO2), as refrigerants. After a series of fatal accidents in the 1920s when methyl chloride leaked out of refrigerators, a search for a less toxic replacement begun as a collaborative effort of three American corporations - Frigidaire, General Motors, and Du Pont. CFCs were first synthesized in 1928 by Thomas Midgley, Jr. of General Motors, as safer chemicals for refrigerators used in large commercial applications1. Frigidaire was issued the first patent, number 1,886,339, for the formula for CFCs on December 31, 1928. In 1930, General Motors and Du Pont formed the Kinetic Chemical Company to produce Freon (a Du Pont trade name for CFCs) in large quantities. By 1935 Frigidaire and its competitors had sold 8 million new refrigerators in the United States using Freon-12 (CFC-12) made by the Kinetic Chemical Company and those companies that were licensed to manufacture this compound. In 1932 the Carrier Engineering Corporation used Freon-11 (CFC-11) in the world’s first self-contained home air-conditioning unit, called the ‘Atmospheric Cabinet.’

Because of the CFC safety record for non-toxicity, Freon became the preferred coolant in large air-conditioning systems. Public health codes in many American cities were revised to designate Freon as the only coolant that could be used in public buildings. After World War II, CFCs were used as propellants for bug sprays, paints, hair conditioners, and other health care products. During the late 1950s and early 1960s the CFCs made possible an inexpensive solution to the desire for air conditioning in many automobiles, homes, and office buildings. Later, the growth in CFC use took off worldwide with peak, annual sales of about a billion dollars (U.S.) and more than one million metric tons of CFCs produced.”

Above top: Freon was trademarked December 8, 1931 by the forerunner of DuPont, for their line of chlorofluorocarbon refrigerants, which includes R-12.

Above lower: Not 1994 when R-12 was banned, but as early as 1951, Allied Chemical (now Honeywell) received registration for the trade name Genetron. Genetron represents Allied’s R-12 and other CFC refrigerants (which they had actually been selling since 1946).

The search for “better” refrigerant patents
My search of the US Patent and Trademark Office shows that Patent Number 1,886,339 was in deed registered to Charles F. Kettering and assigned to Frigidaire Corporation. While the application is dated December 31, 1928, it was not issued until November 1, 1932. Further research shows that at GM, Midgley—chosen by Kettering—headed up the actual research that eventually invented Freon (CFCs).
But here’s where the dateline gets a little grey. I could find no mention of CFCs nor any specific refrigerant in Kettering’s and Frigidaire’s patent. It merely describes a “Refrigerating Apparatus.” Below are four other patents that appear to be more relevant to chlorofluorocarbons used as refrigerants.

1. Patent Number 1,833,847 was issued November 24, 1931 (reissued August 7, 1934) to Thomas Midgley, Jr., Albert L. Henne and Robert R. McNary, all of Ohio, for “Heat Transfer.” The original application was filed February 8, 1930.

I believe that Alexander and Fairbridge erred. Number 1,833,847 appears to be not only the patent for “Freon,” but also for the refrigeration process and essentially “air conditioning.” It describes exactly what the invention covers (production of refrigeration, changing the physical state by condensing or evaporating, latent heat and a halo-fluoro derivative of an aliphatic hydrocarbon, etc.), and it does so in laymen’s terms.

Opening paragraphs:
“This application relates to the art of transferring heat from one pint to another and specifically to the art of refrigeration.

Heretofore, as far as we are aware, refrigerants and heat transfer agents have been chosen chiefly for their boiling points and stability in the refrigerating or heat transfer cycle irrespective of other desirable properties, such as non-inflammability and non-toxicity.

It is the object of our invention, on the other hand, to provide a process of refrigeration and, generically, a process of heat transfer in which these desirable properties, such as non-inflammability and non-toxicity, are obtained in combination with the desired boiling points.”

So there you have it, a new, safe refrigerant; exactly what was needed in 1931.

Here’s more from this patent:
“Obviously our invention is not limited in its application to any specific form of apparatus for carrying out the mode of operation described and it will not be necessary for a complete understanding of the invention to show a specific embodiment of apparatus. Nor is the present invention limited to the examples set forth for a particular advance of the present invention resides in the fact that a great number of new refrigerants with graduated properties is rendered available, and that one is accordingly enabled to secure the most suitable refrigerant for varied purposes.

We claim:

1. The process of refrigeration, which comprises condensing a halogen derivative of an aliphatic mono fluoride and then evaporating the said derivative in the vicinity of a body to be cooled…

6. The process of refrigeration which comprises condensing difluoro-dichloro methane and then evaporating it in the vicinity of a body to be cooled.”

Here are the other three patents.
2. June 18, 1935: Herbert Wilkins Daudt and Mortimer Alexander Youker were issued Patent Number 2,005,706 for “Organic Fluorine Compound.” It was assigned to Kinetic Chemical Inc., of Wilmington, Delaware, the forerunner of DuPont. It’s opening paragraph: “This invention relates to organic fluorine compounds, more particularly fluorinated derivatives of acyclic hydrocarbons and a process of the production thereof.”

3. July 9, 1935: Patent Number 2,007,706, filed January 30, 1931 was issued to Albert L. Henne and General Motors Corporation. Titled “Manufacture of Fluorated Aliphatic Compounds,” Henne states “this invention relates to chemical processes for the manufacturer of fluoro and/or halo-fluoro derivatives of aliphatic hydrocarbons, and more particularly, of halogen derivatives of the methane homologs having relatively high melting points.”

4. Patent Number 1,953,216, issued April 3, 1934 to Howard M. Elsey and assigned to Westinghouse Electric & Manufacturing Company appears to accidentally cover CFC refrigerants. While it’s titled “Insulating Liquid” and is targeted to electrical apparatus with liquid insulators, one of Elsey’s claims is “… As a new composition of matter a fluorinated mixture of hydrocarbons that is liquid at ordinary temperatures and solidifies below approximately -1° C.”

Patents don’t last forever, those for “CFC Refrigerants'” ran out in the ‘50s
Assuming their term is a maximum of twenty years, all of these patents ran out in the early 1950s. That means GM’s, Frigidaire’s, Kinetic’s, Westinghouse’s and yes, even DuPont’s patent on “Freon,” had run out long before the ozone layer was discovered to be suffering.

Proof of that also appears in the November 5, 1946 registration of the trademark Genetron®. General Chemical Company Corporation, later Allied Chemical, then Allied-Signal and now Honeywell Inc., claimed rights for: “Normally gaseous halogenated hydrocarbons; normally gaseous chemicals for use in propelling parasiticides (sic) and dispersing them in aerosol form.” No mention of refrigerants, but they declare first usage on January 4, 1946. On May 12, 1951 they again received registration for “genetron” with a Goods and Service claim of: “Halogenated hydrocarbons sold as such as chemicals of commerce.”

Just think how many millions of car owners out there were crediting all that cool air to the magic of Freon, when in fact they were being cooled by Genetron!

So, DuPont’s expiring patent did not cause the switch to R-134a. Thankfully, there were four major chemical manufacturers whose tooth-and-nail fighting for many years kept the price of cool air affordable to all. The switch to HFCs was an environmental-political decision that I expect was initially opposed vigorously by all of these manufacturers. When change became inevitable, they too had to jump on board. Check out the follow-up article: “SNAP Manufacturers.”                     $$$

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