"Security interest" means an interest in personal property or fixtures that secures payment or performance of an obligation. “Security interest” includes any interest of a consignor and a buyer of accounts, chattel paper, a payment intangible, or a promissory note in a transaction that is subject to COMM Division 9. “Security interest” does not include the special property interest of a buyer of goods on identification of those goods to a contract for sale under COMM 2401. (COMM 1201(35); CCP 481.223)