Abstract: A recording apparatus capable of recording data either in a current-used format or a new format on a recording medium accommodated in a current-used tape cassette or a new tape cassette. The recording apparatus comprises a first writing prohibition detection switch to be inserted to an discrimination hole formed on both cassettes and receded in accordance with an open/close state of a writing prohibition discrimination hole provided on the current-used cassette, a second writing prohibition detection switch to be receded in accordance with an open/close state of a writing prohibition discrimination hole formed in the new tape cassette, and a cassette type detection switch to be inserted to an discrimination hole formed in the new tape cassette and receded by a side surface of the current-used cassette. A control circuit discriminates a new tape cassette from the current-used tape cassette.

Abstract: When a medium casing is moved deep into a device, a reference guide pin with a greater length provided in a driving-device body is first inserted into a first positioning hole of the medium casing and a subsidiary guide pin is subsequently inserted into a second positioning hole. This implies that the medium casing is guided deep into the device on the basis of the reference guide pin having a greater diameter. Therefore, even when the medium casing is inserted in a displaced state in a direction orthogonal to the insertion direction, such displacement can be compensated for gradually with the movement of the medium casing. This ensures proper connection between a plurality of external terminals of the medium casing and a plurality of connector pins of the driving-device body.

Abstract: A magnetic tape cartridge includes a reel around which a magnetic tape is wound, a cartridge casing accommodating the reel rotatably, a reel locking member, a biasing member, a spider, and a lubricant. The reel locking member includes a convex sliding portion and engages with the reel to block a rotation thereof. The biasing member biases the reel locking member so that the reel locking member engages with the reel. The spider includes a supporting surface that comes into contact with the sliding portion and has a concave portion concaved at substantially the center thereof, and a wall portion that surrounds the supporting surface, the spider pushing and moving the reel locking member against a bias force of the biasing member to release the engagement between the reel locking member and the reel. The lubricant is applied between the sliding portion and the supporting surface.

Abstract: A cartridge case of an information recording medium includes a case main body where a guide part is disposed on an inner surface of a top plate, a tape reel that includes a hub in the shape of a bottomed-cylinder and is rotatably enclosed inside the case main body, and a locking member that is guided in a state where rotation is restricted by the guide part, is enclosed within the case main body so as to be capable of moving in a direction toward and away from a base plate of the hub, and restricts rotation of the tape reel. The guide part includes a cylindrical first convex part disposed on the inner surface and a plate-like second convex part disposed on the inner surface. The locking member includes a main part, a cylindrical third convex part that is disposed on the main part and engages the first convex part, and a plate-like fourth convex part that is disposed on the main part and contacts the second convex part to restrict rotation of the locking member.

Abstract: A recording tape cartridge has a door with a first guard portion provided on the upper end of the door in the height direction and having a first through-hole through which a support axis is inserted; and a second guard portion provided on the lower end of the door in the height direction and having a second through-hole through which a support axis is inserted. A torsion spring is provided between the first guard portion and the second guard portion.

Abstract: The write protect mechanism provides a method for identifying the write protect state of the tape media enclosed in a tape cartridge from at least two orientations. A write protect switch on the front side of the tape cartridge housing moves to block the write protect aperture on the side of the tape cartridge housing when the write protect switch is in the write enable position and away from the aperture in the write protect position. A write protect indicator on the tape cartridge top cover includes a window that allows the user to view the position of the write protect switch by viewing the top of the switch. The top of the switch may include an arrow that moves corresponding to the position of the write protect switch, thus providing a means for the user to determine the write protect state. Human readable icons or color combinations on the write protect switch and/or adjacent to the write protect indicator clearly indicate the write protect state of the tape media enclosed within the tape cartridge.

Abstract: The recording medium cartridge accommodates a recording medium such as a magnetic tape, a optical and/or magnetic disk, or the like in a cartridge body having an upper half and a lower half. A non-contact type memory device storing information, for example, given when producing the cartridge is provided in a reel of at least one of upper and lower flanges of a tape reel or on a surface facing to the tape winding surface of the body in the cartridge accommodating the tape reel wound with the tape, or in a recessed portion formed in at least one of a bottom surface of the lower half and an upper surface of a slider or in the slider in the cartridge having the slider, or in a transparent window of the body. A part of at least one of the upper and lower halves that corresponds to the memory device may be notched. The memory device may be welded together when fitting other members.

Abstract: A leader tape where an non-magnetic under layer that contains a powder and a binder and a magnetic upper layer are sequentially laminated on at least one face of a support, in which F5 values of the support in a machine direction (MD) and in a transverse direction (TD) are from 80 to 120 MPa respectively, the F5 value in MD is larger than that in TD, and a difference between the F5 value in MD and that in TD is 15 MPa or less.

Abstract: A magnetic tape cartridge includes a cartridge case, a pair of cylindrical hubs rotatably provided in the cartridge case, and a magnetic tape laid between the hubs and wound around outer peripheries of the hubs. Each of the hubs has an inner diameter portion provided with a height-position determining member. The height-position determining member determines a height position of the hub in the magnetic tape cartridge by contacting a driving shaft inserted in the hub when the magnetic tape cartridge is mounted in a magnetic recording and reproducing apparatus.

Abstract: A magnetic recording medium comprising a non-magnetic support, at least one primer layer formed on one surface of the non-magnetic support, comprising a non-magnetic powder and a binder resin, at least one magnetic layer formed on the primer layer, comprising a magnetic powder and a binder resin, and a back layer formed on the other surface of the non-magnetic support, wherein the magnetic powder contained in the uppermost layer of the magnetic layer is a rare earth metal-iron type magnetic powder of substantially spherical or ellipsoidal particles comprising a rare earth element and iron or a transition metal which comprises iron, and has a number average particle size of 5 to 50 nm and an average axis ratio of 1 to 2, and the total thickness of the magnetic recording medium is less than 6 ?m. This magnetic recording medium can achieve an excellent block error rate.

Abstract: A tape cartridge includes a case, a magnetic tape stored in the case, a movable member slidably or movably mounted on the case and having a display portion visible from an outside of the case, a plurality of management information sets about the tape cartridge are displayed on the display portion, and a plurality of the information sets include one or more information sets different from each other.

Abstract: A tape drive having a single reel data storage cartridge disposed therein is provided. The single reel data storage cartridge includes a housing having an access window and a reel rotatably disposed within the housing and having storage tape wound on the reel. A guide surface is further disposed within the housing such that the tape extends from the reel to the guide surface before extending to the access window. The tape drive includes at least a first guiding element, a data transducer, and a take-up reel, wherein the storage tape extends from the supply reel to the guide surface before extending through the access window to the first guiding element, and the storage tape is guided within the tape drive adjacent a data transducer, and wound on the take-up reel.

Abstract: An object is to provide a leader tape which suppresses the increase of dropout resulting from imprinting of the drive reel or leader block part due to storage for a long time or running at a high temperature and hardly causes the edge damage of a magnetic tape, and also provide a magnetic tape cartridge using the leader tape. 1) A leader tape comprising a support having provided on at least one surface thereof a coating layer comprising a powder material and a binder, wherein the center line average roughness (Ra) on at least one surface of the leader tape is from 10 to 60 nm and the friction coefficient against an Al2O3/TiC member is from 0.1 to 0.

Abstract: A recording medium cartridge and producing method thereof, such that slidability of resin-fabricated members of different materials against one another can be assured even in conditions in which impacts are successively applied. The recording medium cartridge is provided with a recording medium T and a plurality of resin-fabricated components. A mixture C of perfluoropolyethylene and polytetrafluoroethylene is interposed at boundary surfaces at which the resin-fabricated components of different material slide against one another and/or at boundary surfaces at which the resin-fabricated components of different material slide against one another.

Abstract: In one example of one aspect of the invention, a single reel data storage cartridge is provided. The single reel data storage cartridge includes a housing having an access window and a reel rotatably disposed within the housing and having storage tape wound on the reel. A guide surface is further disposed within the housing such that the tape extends from the reel to the guide surface before extending to the access window. The guide surface thereby increases the tape path from the reel to guiding elements within a tape drive to reduce the force imparted on the tape edge during guiding.

Abstract: In an optical storage, a base is defined in a bottom of a space which receives a disk. A drive unit is mounted on the base for turning the disk around a drive axis. A shroud is defined in a side of the space, and a cover is defined in a top of the space. The cover has a slanted line extended from a central portion of the cover toward the shroud at an upward inclination with respect to a disk plane when seen in a cross-section taken along a line perpendicular to the disk plane.

Abstract: The magnetic tape cassette has a base with an opening for forming a transparent window and a transparent resin-made window member to be installed in the opening. The window member is provided with an engaging unit which is to be fitted into the base at an angle and the base is provided with an engaging portion that is formed at an angle in correspondence to the engaging unit and the window member is installed in the opening by being fitted in at an angle.

Abstract: A leader tape to be spliced in a butting manner to a leading end of a magnetic tape, the leading end being mechanically cut in a tapered shape, wherein the leader tape has a surface roughness RZ (RZ complies with JIS B0601-1994) of 5 ?m or less.

Abstract: The magnetic tape cassette has a base with an opening for forming a transparent window and a transparent resin-made window member to be installed in said opening. The window member is provided with an engaging unit which is to be fitted into the base at an angle and the base is provided with an engaging portion that is formed at an angle in correspondence to the engaging unit and the window member is installed in the opening by being fitted in at an angle.

Abstract: A leader tape that is joined at an end portion of a recording tape wound on a reel and that, when pulling out the recording tape, is pulled out by a pullout member of a drive device and conveyed on a predetermined path by guide members of the drive device, wherein recessed portions are formed in a surface of the leader tape that abuts with the guide members, is provided.

Abstract: Sliding resistance at a time when a locking member is moved between a locking position and an unlocking position with respect to a reel can be lessened, and it is possible to avoid bringing about trouble with a drive device or the like. In a recording tape cartridge 10, in which a reel 20, which has a hub 22 on which a recording tape T is wound, is singly and rotatably accommodated within a case 12, a locking member 70 is configured to be able to rotate within a plane orthogonal to a rotation axis direction of the reel 20 around a position which is different from a rotational center of the reel 20.

Abstract: In one example of one aspect of the invention, a single reel data storage cartridge is provided. The single reel data storage cartridge includes a housing having an access window and a reel rotatably disposed within the housing and having storage tape wound on the reel. A guide surface is further disposed within the housing such that the tape extends from the reel to the guide surface before extending to the access window. The guide surface thereby increases the tape path from the reel to guiding elements within a tape drive to reduce the force imparted on the tape edge during guiding.

Abstract: The present invention relates to an object storage device having shaking function having a vertically situated storage cassette, which has multiple object storage points situated one on top of another, and having a drive unit functionally connected to the storage cassette via a first drive connection, comprising at least one drive element for performing a shaking movement of the storage cassette. The present invention also relates to a climatic cabinet having such an object storage device.

Abstract: A reel of a recording tape cartridge has a reel hub formed in a shape of a hollow cylinder; an annular reel gear; an upper flange; a lower flange; and a reel plate. A reel gear is provided coaxially at an outer surface of a floor of the reel hub, and meshes with a driving gear of a rotating shaft of a drive device. A reference surface is provided integrally at an outer side of the floor. The upper flange extends integrally toward a radial direction outer side from an open end of the reel hub. The lower flange is mounted to a floor side end of the reel hub, and opposes the upper flange. The reel plate is fixed to the outer surface of the floor, and is attracted by a magnet of the rotating shaft without being contacted by the magnet.

Abstract: A recording tape cartridge is structured so as to accommodate, within a case, a reel on which is wound a magnetic tape which is a recording medium. The recording tape cartridge has a so-called WORM function such that overwriting of data on a recording region of the magnetic tape where data is already written, is prohibited. Within the case are provided a first memory board which stores data managing information for managing data written on the magnetic tape, and a second memory board which stores WORM managing information for managing writing of data to the magnetic tape.

Abstract: The present invention provides a leader tape, method for manufacturing the same, and a magnetic tape cartridge with a leader tape having surface properties and conductive properties for securing slide durability suitable for a magnetic tape drive using a magnetic tape cartridge of one reel cartridge. A leader tape joined to a starting end of a magnetic tape wound around a magnetic tape reel of a one reel cartridge, comprising: a base material; and a conductive slide layer formed on at least one surface of the base material, the surface of the conductive slide layer having a surface electrical resistance value of 102 ?/square to 1010 ?/square and a surface roughness Ra of 0.5 ?m to 1.5 ?m.

Abstract: A tape cartridge including a tape capable of recording and reproducing a high accuracy servo signal, by preventing a deformation of the tape by preventing turning up of a front end portion of a tape when the front end portion is adhered to a reel hub. The tape cartridge includes the tape, a single reel having a reel hub around which the tape is wound and a cartridge case in which the reel is installed, and the front end portion of the tape is adhered to the reel hub, and each corner of the front end portion of the tape is chamfered and chamfers are formed.

Abstract: Described herein are centering systems, including cartridge reels, reel drivers, and methods of using them. Aspects of the invention may include cartridges, tape drives, and systems of using the cartridge reels and reel drivers. A centering system may comprise a cartridge reel having gear teeth and a guide channel. The guide channel may mate with an alignment ring on a reel driver to center the cartridge reel with respect to the reel driver so that gear teeth on the reel driver may properly engage the gear teeth on the cartridge reel. Thus, the centering system (or components of the centering system) may be used to prevent misalignment and slipping between a cartridge reel and a reel driver.

Abstract: A tape cartridge (54) for use in a tape drive (46) having a tape head (260) includes a cartridge housing (272), a cartridge reel (274) and a tape (278). The cartridge reel (274) is rotatably secured to the cartridge housing (272). The tape (278) is secured to the cartridge reel (274). The tape (278) can include a storage tape (278D) that stores data and a lapping tape (278L) that laps the tape head (260). In one embodiment, the storage tape (278D) and the lapping tape (278L) are spliced together. The ratio of storage tape (278D) to lapping tape (278L) can be at least approximately 0.01:1. The lapping tape (278L) can include a diamond material having a grit of between approximately 0.1 micron and 1.0 micron. In one embodiment, the tape (578) can include a first lapping tape (578L1) and a second lapping tape (578L2) that has a different grit than the first lapping tape (578L1). In another embodiment, the tape (678) also includes a cleaning tape (678CL) that cleans the tape head (260).

Abstract: A data storage device is disclosed with a housing sized for a tape drive. A tape reel is mounted for rotation within the housing and a guide is mounted in the housing spaced apart from the tape reel. A first end of a data tape segment is mounted to the tape reel and a second end is not mounted to the tape reel. A structural tape segment has a pair of ends mounted between the first and second ends of the data tape segment for structurally enhancing an intermediate region of the data tape segment. In another embodiment, a structurally enhanced intermediate region is advanced to a read/write region of the data storage device during storage of the device for preventing inadvertent damage to the data tape.

Abstract: A tape cartridge capable of recording and reading out large and small tape cartridges with different widths is provided. The tape cartridge comprises a pair of right and left hubs for winding a tape which is winded off from one hub and is wound around the other hub via tape guides. A passage for light injection and a passage for light ejecting of the tape end detection light are opened respectively on a side wall of a case of a main body facing a tape traveling path between the tape guide and the hub, and an optical path inverted body facing a pair of passages across the tape traveling path is arranged in the case of the main body. One of the passages for light injection and the passages for light ejecting in the large and small tape cartridges is formed at a prescribed distance from the reference surface.

Abstract: A single reel tape cartridge capable of achieving high-speed read/write access to tapes at high density by enhancing the molding accuracy of lower flange and eliminating inclination and waviness of flange walls is provided. A reel incorporated in a main case is composed of an upper flange, a lower flange, and a boss which is integrally plastic-molded with the lower flange for taking up a magnetic tape. An exit port for allowing an operating nail of an unlock tool to get in and out is open on the bottom wall of the boss. The lower flange is molded in the state that a bridging piece extending along radial direction of the lower flange is formed in the exit port, so that resin flow to the flange wall radially outside the exit port is promoted. The bridging piece is removed after the lower flange is molded.

Abstract: A data storage cartridge comprises data storage media configured to store data for read and/or write access, wherein the data may be arranged in a plurality of partitions; and a plurality of cartridge memories. Each cartridge memory comprises a communication interface and a memory, wherein the information of the memory is formatted to allow association with at least one of the plurality of partitions of the data storage media. Thus, each of the cartridge memories may have a separate user and provide access for that user to a separate partition or subset of partitions.

Abstract: A tape cartridge capable of preventing emission of vibrating sounds and occurrence of abrasion at a usage time when a reel hub unit rotates at a high rotating speed. The tape cartridge has a single reel hub unit rotatably accommodated in a case and having its periphery wound with a tape-shaped recording medium, a brake lock member including an engaging portion for engaging a reel hub unit to restrict rotation of the reel hub unit when in non-use, and a flat surface bearing portion provided substantially at a central part of the brake lock member, wherein the central axis of said flat surface bearing portion of the brake lock member is parallel with and offset from the rotating central axis around which said brake release member rotates together with said reel hub unit.

Abstract: A tape cartridge which, in a state in which a reel cannot rotate, restricts movement of a braking member and restricts movement of the reel. In a state in which engaging walls of locking members are engaged with a top edge portion of a reel hub, step portions and the engaging walls abut a top surface of an upper flange and an inner peripheral surface of the reel hub. In this way, when the cartridge is not in use, vertical direction movement of the reel is restricted. Even if impact of a drop or the like is applied to the recording tape cartridge 10, the reel does not rise up. Accordingly, a problem such as the braking member tilting and becoming anchored does not arise. It is also possible to overcome a problem of the upper flange or a lower flange of the reel breaking due to the reel moving within a case when the tape cartridge is dropped.

Abstract: A leader tape in which an non-magnetic under layer that contains a powder and a binder and a magnetic upper layer are sequentially laminated on at least one side of a support, a center line average roughness (Ra) of a surface of the support is from 30 to 50 nm, and a center line average roughness (Ra) of the multi layer coated surface is larger than that (Ra) of an opposite surface of the support, and the difference is at most 4 nm.

Abstract: A recording tape cartridge is structured so as to accommodate, within a case, a reel on which is wound a magnetic tape which is a recording medium. The recording tape cartridge has a so-called WORM function such that overwriting of data on a recording region of the magnetic tape where data is already written, is prohibited. Within the case are provided a first memory board which stores data managing information for managing data written on the magnetic tape, and a second memory board which stores WORM managing information for managing writing of data to the magnetic tape.

Abstract: A recording tape cartridge with high strength and resistance to deformation around an opening aperture of a case, which opening aperture is for drawing out recording tape. The recording tape cartridge is provided with a leader block at a distal end of a magnetic tape. Left and right peripheral portions of this leader block are defined by wall portions. The leader block is mounted and removed at a leader block-retaining portion, which is an opening portion which penetrates through the case vertically. An opening aperture for drawing out the magnetic tape from the case is formed at a base portion of the leader block-retaining portion. Because the wall portions are provided, the leader block-retaining portion does not have free-standing end portions at any of a front wall at a front wall side thereof, a ceiling plate and a floor plate, and strength of the leader block-retaining portion is high.

Abstract: A reel has: a hub which is shaped as a cylindrical tube having a bottom, and around which a recording tape is wound; a flange provided at an end portion of the hub, and holding a widthwise direction end portion of the recording tape; a reel plate attracted by magnetic force to a rotating shaft of a drive device; and a pin for caulking which projects from a bottom surface of a floor wall of the hub, for attachment of the reel plate. A positioning portion, which positions the pin for caulking, is provided at a top surface of the floor wall of the hub.

Abstract: The recording medium cartridge of the invention can keep superiority in supplying a power source and realize a high capacity of an IC chip and an improvement of communications performance, with a cartridge memory being able to be flexibly arranged in a cartridge case.

Abstract: A cartridge case includes a case main body, a tape reel that includes a hub in the shape of a bottomed-cylinder and is rotatably enclosed inside the case main body, and a locking member on whose base part ring-shaped first teeth are formed, which is energized toward an inner surface of a base plate of the hub, is enclosed within the case main body so as to be capable of moving in a direction toward and away from the base plate, and restricts rotation of the tape reel. The tape reel includes a plurality of arc-shaped convex parts that are disposed on a circle about an axis of the hub on the inner surface of the base plate and support the locking member that has moved toward the base plate. Second teeth that engage the first teeth are formed on an upper part of at least one of the convex parts. A contact surface that contacts edges of the first teeth without engaging the first teeth is formed on an upper part of at least one of the convex parts.

Abstract: A tape cartridge improving an assembling property of a leader member, for leading out a tape-shaped recording medium, to which a leading edge of the tape is fixed. The tape cartridge accommodates a reel hub unit rotatably, for winding a magnetic recording medium on its periphery, and includes a leader member for holding and fixing a leading edge of the magnetic recording medium. The leader member has a pin member having a pair of collar portions between which the magnetic recording medium is positioned, and a clamp member fitted in between the collar portions from through an opening so formed in a longitudinal direction of a cylindrical body as to extend to end surfaces on both sides of the cylindrical body, and clamping the magnetic recording medium between the pin member and the clamp member itself. Chamfered portions are provided at edge portions of the opening of the clamp member.

Abstract: A data storage tape cartridge used in a tape transport apparatus that incorporates air bearing technology is provided. The tape cartridge includes a housing for storing the data storage tape and a compressible filter. The filter is located proximate to an opening, or air inlet, that is in communication with the housing interior. The housing may also have a second opening, or air outlet, in communication with the housing interior such that the filter is interposed between the inlet and the outlet. Further, the housing may include a storage region to retain the filter in the compressed state. The filter and the storage region may have congruent geometries. A method of supplying filtered air to a tape transport apparatus is also provided. The method contemplates drawing ambient air through the filter and passing it directly through the outlet opening for use by the tape transport apparatus.

Abstract: A tape cartridge is configured to include a cartridge case, a hub, around which a magnetic tape is wound around and is housed in the cartridge case rotatably, and a drive apparatus for driving the hub to rotate, the drive apparatus being arranged between a bottom portion of the hub and the cartridge case.

Abstract: A disc cartridge including a disc medium which is loaded into a drive device and into/from which information can be recorded/reproduced; a case that houses the disc medium rotatably; a disc opening from which the disc medium provided into the case can be taken out; and a disc taking-out history detecting portion that can be deformed recognizably and irreversibly according to an operation for firstly taking out the disc medium from the case, is provided to judge whether a disc medium is taken out of the case.

Abstract: A recording tape cartridge (10) includes: a case (12) that houses a reel (40) onto which a recording tape is wound, the case comprising an upper case (14) including a top plate (14A) and a lower case (16) including a bottom plate (16A); lock members (90) that are disposed, so as to be slidable in a radial direction of the reel, in an attachment portion (60) formed on an inner surface of the top plate, the lock members being movable between a rise/fall lock position, at which the lock members are intervened between an upper surface of the reel and the top plate to prevent movement in an axial direction of the reel, and a rise/fall allowance position, at which the lock members are retracted from between the upper surface of the reel and the top plate to allow movement in the axial direction of the reel; and projecting portions (70A) that are formed on the inner surface of the top plate and project towards the lock members so that the lock members do not fall out of the attachment portion at least when the case

Abstract: In a recording tape cartridge, an inclined opening obtained by notching a corner portion on the side of loading to a drive apparatus is closed when a door is in a close position in which the door is inclined from a direction matching the loading direction and is open when the door is in an open position along a right side wall. The door is guided by first and second guide grooves and moves between the close position and the open position while changing its orientation by a urging force of a compression coil spring disposed along the right side wall or a moving force transmitted from an operation projection which comes into engagement with the engagement member of the drive apparatus.

Abstract: A cartridge for operatively housing a recording/playback medium comprising a first spool and a second spool located at offset positions inside a cartridge shell body; a recording/playback medium of a fixed width and length wound around the first and second spools; and a plurality of slant tape guides positioned between the first and second spools for guiding the recording/playback medium and for creating a helical scan tape wrap angle in connection with a plurality of main tape guides, the plurality of main tape guides being positioned between the first and second spools. The cartridge shell body comprises a plurality of pull out arm assemblies serving as enclosure doors for a bottom surface of the cartridge shell body, the pull out arm assemblies further serving as semicircular side walls of the cartridge shell body; a top plate; and opposing end plates formed perpendicular to the pull out arm assemblies and the top plate.

Abstract: In a recording tape cartridge, a compression coil spring urges a reel downward via a brake member. Due to the biasing force of the spring, a gear of the brake member securely meshes with a gear inside a reel hub preventing the reel's inadvertent rotation. The biasing force urges lock members outward in a radial direction from the center of a mount or the reel. Engagement portions of the lock members engage with an upper edge of the hub. The outer side surfaces of the engagement portions press against the inner peripheral surface of the hub, and ends of the engagement portions at a further outer side than the body portions intervene between the upper surface of an upper flange and the inner surface of a top plate to prevent rotation of the reel and to control movement of the reel in either a radial or an axial direction.

Abstract: A recording tape cartridge including at least a door opening and closing an opening by rotating around a supporting shaft provided at a front wall side; an allowing portion formed in the door, which allows avoidance of contact between the door and a distal end surface of a leader tape when the door closes the opening; and a guide portion formed at the allowing portion, and abutting the distal end portion of the leader tape, and formed to be thick-walled in a direction of making the distal end portion of the leader tape move away from the side wall. When the door closes the opening of the recording tape cartridge, a predetermined clearance is ensured between the distal end surface of the leader tape and a deepest surface of the allowing portion.