Coolant patents are a good source of technical info about coolant. They are hard to read and present the product in the best light. If you read some of these coolant patents you get a sense they were focusing on metal corrosion protection, which the extended life coolants are good at, but not on gasket compatibility.
Here is the patent that appears to be for Prestone dexcool/extended life. In this excerpt it claims Havoline Dexcool uses sebacic acid. Isn't that what Japanese coolant uses lol? Sebacic acid=carboxylic acid=2-EHA I think:
Quote:
However, such organic acid formulations also suffer from a number of problems. For example, sebacic acid, which is used in several commercial antifreezes (e.g., Texaco's "Havoline" Extended Life AntiFreeze/Coolant; General Motors' "Dex-Cool" Anti-Freeze/Coolant; Canadian Tire's "Motomaster" Long Life and is currently used in the standard formulation set forth by the British Military (see Specification TS 10177, "Antifreeze, Inhibited Ethanediol, AL-39"), is more difficult to use commercially since it is commercially available as a solid, and as such requires heat to dissolve it in a heat transfer fluid. Also, sebacic acid is generally more expensive and difficult to obtain commercially since currently there is only one domestic industrial supplier (Union Camp Corporation). See SAE SP811, pp. 141-42. Also, sebacic acid and higher di-carboxylic acids, tend to have poor solubility in antifreeze formulations using hard water. See U.S. Pat. No. 4,578,205, col. 1, lines 52-64.
Prestone patent
That link also has some references to patents in regard to OATS going back to the early 80's. Lol they've been working on this OATs since then and still didn't get it right. It's some dry reading but you can gain some info from it.
Here is the patent that appears to be for Prestone dexcool/extended life. In this excerpt it claims Havoline Dexcool uses sebacic acid. Isn't that what Japanese coolant uses lol? Sebacic acid=carboxylic acid=2-EHA I think:
Quote:
However, such organic acid formulations also suffer from a number of problems. For example, sebacic acid, which is used in several commercial antifreezes (e.g., Texaco's "Havoline" Extended Life AntiFreeze/Coolant; General Motors' "Dex-Cool" Anti-Freeze/Coolant; Canadian Tire's "Motomaster" Long Life and is currently used in the standard formulation set forth by the British Military (see Specification TS 10177, "Antifreeze, Inhibited Ethanediol, AL-39"), is more difficult to use commercially since it is commercially available as a solid, and as such requires heat to dissolve it in a heat transfer fluid. Also, sebacic acid is generally more expensive and difficult to obtain commercially since currently there is only one domestic industrial supplier (Union Camp Corporation). See SAE SP811, pp. 141-42. Also, sebacic acid and higher di-carboxylic acids, tend to have poor solubility in antifreeze formulations using hard water. See U.S. Pat. No. 4,578,205, col. 1, lines 52-64.
Prestone patent
That link also has some references to patents in regard to OATS going back to the early 80's. Lol they've been working on this OATs since then and still didn't get it right. It's some dry reading but you can gain some info from it.
