Provided is a recording tape cartridge including: a case that accommodates a reel on which a recording tape is wound and includes a reference surface that serves as a reference in an axial direction of the reel in a case where the case is loaded into a drive device; noncontact communication mediums on which individual information is recorded, the noncontact communication mediums being accommodated in the case in a state where at least two noncontact communication mediums overlap each other and having a plate shape; and a supporting portion that is formed in the case and supports the noncontact communication mediums such that the noncontact communication mediums are disposed while being inclined with respect to the reference surface at an angle of approximately 45 degrees.

Provided is a recording tape cartridge including: a case that accommodates a reel on which a recording tape is wound and includes a reference surface that serves as a reference in an axial direction of the reel in a case where the case is loaded into a drive device; noncontact communication mediums on which individual information is recorded, the noncontact communication mediums being accommodated in the case in a state where at least two noncontact communication mediums overlap each other and having a plate shape; and a supporting portion that is formed in the case and supports the noncontact communication mediums such that the noncontact communication mediums are disposed while being inclined with respect to the reference surface at an angle of approximately 45 degrees.

In the magnetic tape, in a case where a maximum value of an absolute value of a difference between a servo band spacing obtained before storage in an environment of a temperature of 32° C. and relative humidity of 55% and a servo band spacing obtained after storage in the environment for a storage time T is set to A, and T is defined as 24 hours, 48 hours, 72 hours, 96 hours, or 120 hours, a medium life calculated by a linear function of A and a logarithm log.sub.eT of T, that are derived from a value of A and a value of the logarithm log.sub.eT of T obtained for each T is 3 years or longer. The medium life is T in a case where the A satisfies Equation 1: A=1.5−B.

In the magnetic tape, in a case where a maximum value of an absolute value of a difference between a servo band spacing obtained before storage in an environment of a temperature of 32° C. and relative humidity of 55% and a servo band spacing obtained after storage in the environment for a storage time T is set to A, and T is defined as 24 hours, 48 hours, 72 hours, 96 hours, or 120 hours, a medium life calculated by a linear function of A and a logarithm log.sub.eT of T, that are derived from a value of A and a value of the logarithm log.sub.eT of T obtained for each T is 3 years or longer. The medium life is T in a case where the A satisfies Equation 1: A=1.5−B.

A non-contact communication medium according to one disclosed embodiment includes a memory unit, a power generation unit, a power monitoring unit, and a capacitance control unit. The power generation unit includes a resonant circuit and a rectification circuit, and generates electric power to be supplied to the memory unit. The resonant circuit includes an antenna coil and resonant capacitance unit having a variable capacitance value, and the rectification circuit rectifies a resonant output of the resonant circuit. The power monitoring unit includes a current adjustment element, a reference voltage generation source, and an operational amplifier. The operational amplifier controls the current adjustment element such that an output voltage of the rectification circuit is equal to a reference voltage from the reference voltage generation source. The capacitance control unit is configured to control the resonant capacitance unit on the basis of an output of the operational amplifier.

The magnetic tape includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder, in which an edge portion Ra which is an arithmetic average roughness Ra measured at an edge portion of a surface of the magnetic layer is 1.50 nm or less, a central portion Ra which is an arithmetic average roughness Ra measured at a central portion of the surface of the magnetic layer is 0.30 nm to 1.30 nm, and a Ra ratio (central portion Ra/edge portion Ra) is 0.75 to 0.95.

The magnetic tape includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder, in which an edge portion Ra which is an arithmetic average roughness Ra measured at an edge portion of a surface of the magnetic layer is 1.50 nm or less, a central portion Ra which is an arithmetic average roughness Ra measured at a central portion of the surface of the magnetic layer is 0.30 nm to 1.30 nm, and a Ra ratio (central portion Ra/edge portion Ra) is 0.75 to 0.95.

A noncontact communication medium includes a processor, and a memory incorporated in or connected to the processor, and performs noncontact communication with an external communication device. The memory has a storage block where information determined depending on a specification of a magnetic tape cartridge, in which the noncontact communication medium is mounted, is stored, and the storage block has an identifier storage field. The processor is configured to write an identifier given from the external communication device to the noncontact communication medium, in the identifier storage field, and execute locking processing of locking the identifier storage field in response to a specific command given from the external communication device to the noncontact communication medium.

A noncontact communication medium includes a processor, and a memory incorporated in or connected to the processor, and performs noncontact communication with an external communication device. The memory has a storage block where information regarding an attribute of the noncontact communication medium is stored and that includes a plurality of storage fields. The plurality of storage fields include a specification-independent storage field where information independent of a specification of a magnetic tape cartridge, in which the noncontact communication medium is mounted, is stored. The processor is configured to write accompanying information regarding the magnetic tape cartridge in the specification-independent storage field in response to an instruction given from the external communication device to the noncontact communication medium by the noncontact communication.

A noncontact communication medium includes a processor, and a memory incorporated in or connected to the processor, and performs noncontact communication with an external communication device. The memory has a storage block where information regarding an attribute of the noncontact communication medium is stored and that includes a plurality of storage fields. The plurality of storage fields include a specification-independent storage field where information independent of a specification of a magnetic tape cartridge, in which the noncontact communication medium is mounted, is stored. The processor is configured to write accompanying information regarding the magnetic tape cartridge in the specification-independent storage field in response to an instruction given from the external communication device to the noncontact communication medium by the noncontact communication.