principled contradictory of exchange contracts with Mere subject matter of credit papers

Todays, banking exchange facilities is one of the new Islamic jurisprudence issues that its legal process arise within commutative contract and in way of exchange of real property in consideration of cash credit paper (money) and commercial negotiable instruments. Although this process has criteria such as legitimacy of motive of contract,proportion between inflation rate and credit paper rate and importance of time as a part of price, but non principled act of banking system in credit paper is issue that may deprive above mentioned papers from value and make formation of exchange contract as usury lending and as a result, confront monitory transferring with usury consequences. This research aims to study above mentioned papers financial value, descriptively and analytically. And briefly can be said that deprive of ownership character from these paper, cause usury in these contracts. And finally, has remembered statutory tests free interest banking with emphasis on need to take consideration to form of favourity of credit paper.