Beside the issue of what it is, you have to consider if it is a liquid you can only take a one quart size bag of liquids on the plane. So, unless they will all fit in one or two (one for each of you quart size ziplocs, not only are you facing an issue if it is considered flamable but will it get past the liquids requirement.
Also, if they consider this a flammable liquid, you may not even be able to check it. Below is the TSA policy. None of these items can be taken on the plane as carry-on or in checked baggage.
Flammable Items Carry-on Checked
Aerosol (any except for personal care or toiletries in limited quantities) No No
Fuels (including cooking fuels and any flammable liquid fuel) No No
Gasoline No No
Gas Torches No No
Lighter Fluid No No
Common Lighters - Lighters without fuel are permitted in checked baggage. Lighters with fuel are prohibited in checked baggage, unless they adhere to the Department of Transportation (DOT) exemption, which allows up to two fueled lighters if properly enclosed in a DOT approved case. If you are uncertain as to whether your lighter is prohibited, please leave it at home. Yes No
Torch Lighters - Torch lighters create a thin, needle-like flame that is hotter (reaching 2,500 degrees Fahrenheit) and more intense than those from common lighters. Torch lighters are often used for pipes and cigars, and maintain a consistent stream of air-propelled fire regardless of the angle at which it is held. Torch lighters continue to be banned. No No
Strike-anywhere Matches - One book of safety (non-strike anywhere) matches are permitted as carry-on items, but all matches are prohibited in checked baggage. No No
Flammable Paints (See Other Items below for non-flammable paints) No No
Turpentine and Paint Thinner No No
Realistic Replicas of Incendiaries No No
NOTE: There are other hazardous materials that are regulated by the FAA. This information is summarized at FAA: Home, click on Passengers, then Preparing to Fly