However, just as surely, if the landlord fails to segregate properly a security deposit, or mingles it with personal funds, the law views such as an illegal conversion of the security deposit (Kelligrew v Lynch, 2 Misc 3d 135[A], 2004 NY Slip Op 50220[U], *2 [App Term, 1st Dept 2004]; LeRoy v Sayers, 217 AD2d 63 [1st Dept 1995]; Sommers v Timely Toys, Inc., 209 F2d 342 [2d Cir 1954]). In such a case, if the tenant has vacated the premises, the right to a refund is immediate and shall not be delayed or postponed until the resolution of a landlord’s claim *967for some or all of the security deposit (LeRoy v Sayers, supra).2 This right to immediate recovery of a security deposit rests upon fundamental principles explored in the leading case of Matter of Perfection Tech. Servs. Press (Cherno-Delecar Realty Corp.) (22 AD2d 352 [2d Dept 1965], affd without op 18 NY2d 644 [1966]), in which the Appellate Division, Second Department, explained:
“[The security deposit law] changed the legal relationship between the [landlord and tenant] from debtor-creditor to trustee-cesízzz que trust. The inability of the commingling landlord to set off claims against the deposit flows from the change in his legal status. [The landlord] does not owe a debt as he once did; he owes a duty not to commingle the deposit with his own funds. Upon a breach of that duty, he forfeits his right to avail himself of the deposit for any purpose. To allow him to set off the deposit against his individual claims is to treat the deposit as a debt and the landlord as a debtor— precisely the situation which [the security deposit law] was enacted to change.” {Id. at 356 [emphasis added].)