Well, (sort of tongue in cheek), I tried looking it up from authoritative sources...
According to the faa, materials that may be carried in checked baggage are regulated by US DOT regulations recorded in cfr 49 sections 101-172.
According to the eclipse msds taken from the photosol web site, Eclipse is classified as a UN1993 hazardous material. According to the dot in cfr 49-172.101 (department of transportation hazardous materials table) UN 1993 decodes to a "flammable liquid n.o.s." which can be carried aboard a passenger aircraft in under 1 Liter quantity.
Of course, that is according to the manufacturer's classification. E2 is not listed with its un code, instead it is accorded an iata id8000 which merely identified it as a class 9 misc hazardous material. Class 9 is the lowest hazard level and is carried by many (most) international carriers usually with some quantity limit far more than that contained in a single small bottle.
On the other hand, almost everyone in the transportation business takes the most conservative interpretation if left to their own devices which would be to classify it as a dot "alcohol, flammable, toxic, n.o.s" which is forbidden unless packaged in accordance with exception 202 which extends that to 1 Liter.
If the toxic element were removed, then the above forbidden moves up to a liter.
Of course, all of this can be changed through application and approval of a shipping exception (aka a license) which would have its own restrictions.
To sum it all up... Nobody will admit that you can carry a liter of this stuff in checked baggage because of the liability of interpreting the regulations incorrectly or possibly because of the way that it is packaged or boxed...I am willing to personally risk carrying half an ounce in my checked baggage.
Don't even think of carrying it aboard the aircraft. It is prohibited not so much because it is flammable, but because it is poisonous. The same dot table specifies a limit of 5 liters of alcoholic beverages in checked baggage.
So, will somebody please check up on this to see if I did it right
-bob