Developer accommodating unit, process cartridge and electrophotographic image forming apparatus

A developer accommodating unit includes: a container, provided with an opening for permitting discharge of a developer, for accommodating the developer; a sealing member for sealing the opening by being mounted on the container and for being peeled from the container to expose the opening; and an unsealing member for unsealing the opening by moving the sealing member to peel the sealing member from the container. The sealing member includes a sealing portion defined in an end side thereof to seal the opening, a holding portion defined in another end side thereof to be held by the unsealing member, and a developer passing portion formed between the sealing portion and the holding portion to permit passing of the developer therethrough.

FIELD OF THE INVENTION AND RELATED ART

The present invention relates to a developer accommodating unit for accommodating a developer, and a process cartridge and an electrophotographic image forming apparatus which include the developer accommodating unit.

The electrophotographic image forming apparatus forms an image on a recording material (medium) by using an electrophotographic image forming process and may include, e.g., an electrophotographic copying machine, an electrophotographic printer (such as an LED printer or a laser beam printer), an electrophotographic facsimile machine, an electrophotographic word processor, and the like. Further, the process cartridge refers to a cartridge, prepared by integrally assembling at least a developing means and a developer accommodating unit accommodating a developer, detachably mountable to a main assembly of the electrophotographic image forming apparatus.

In a conventional electrophotographic image forming apparatus using the electrophotographic image forming process, a process cartridge type in which an electrophotographic photosensitive member and process means acting on the photosensitive member are integrally assembled into a cartridge and this cartridge is detachably mountable to a main assembly of the electrophotographic image forming apparatus is employed.

In such a process cartridge, a type in which an opening provided to a developer accommodating frame for accommodating a developer (toner, carrier, etc.) is sealed with a sealing member, and then a welding portion of as a sealing member is peeled off at the time of use to unseal the opening, thus enabling feeding (supply) of the developer has been widely employed. As an invention in which the opening of the developer accommodating frame is opened, those described in Japanese Laid-Open Patent Application (JP-A) Hei 4-166963, JP-A 2002-169366 and JP-A Sho 63-294582 are disclosed.

In JP-A Hei 4-166963, a constitution in which a toner accommodating portion formed with a sheet film is provided inside the developer accommodating frame and when a user pulls a grip, a developer supplying opening of the toner accommodating portion is opened is described. In JP-A 2002-169366, a constitution in which a winding-up shaft of a sealing member is provided outside the developer accommodating frame is provided and when the winding-up shaft is rotated, the developer supplying opening is opened is described. In JP-A Sho 63-294528, a constitution in which the winding-up shaft of the sealing member is provided inside the developer accommodating frame and when the winding-up shaft is rotated, the developer supplying opening is opened is described.

However, in the constitution described in JP-A Hei 4-166963, the user is required to expend effort such that the user pulls the grip, and the sealing member remains in user's hand. Further, in the constitutions described in JP-A 2002-169366 and JP-A Sho 63-249582, the sealing member is peeled off but it is desired that discharging efficiency of the developer is further improved.

SUMMARY OF THE INVENTION

A principal object of the present invention is to provide a developer accommodating unit capable of eliminating efforts of a user to remove a sealing member and capable of improving discharging efficiency of a developer from a flexible container in which the developer is accommodated.

According to an aspect of the present invention, there is provided a developer accommodating unit comprising: a container, provided with an opening for permitting discharge of a developer, for accommodating the developer; a sealing member for sealing the opening by being mounted on the container and for being peeled from the container to expose the opening; and an unsealing member for unsealing the opening by moving the sealing member to peel the sealing member from the container, wherein the sealing member includes a sealing portion defined in an end side thereof to seal the opening, a holding portion defined in another end side thereof to be held by the unsealing member, and a developer passing portion formed between the sealing portion and the holding portion to permit passing of the developer therethrough.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinbelow, embodiments for carrying out the present invention will be exemplarily and specifically described on the basis of Embodiments with reference to the drawings. However, dimensions, materials, shapes, relative arrangements, and the like of constituent elements described in the following embodiments are appropriately changed depending on constitutions or various conditions of devices (apparatuses) to which the present invention is applied, and therefore the scope of the present invention is not limited thereto unless otherwise specified.

FIG. 1is a sectional view showing a structure of an image forming apparatus B including a developer accommodating unit25(FIG. 2) according to Embodiment 1 of the present invention. The image forming apparatus B is an image forming apparatus using an electrophotographic image forming process. As shown inFIG. 1, the image forming apparatus B includes an image forming apparatus main assembly B1in which an image forming portion Q for forming an image is provided. The image forming portion Q includes a photosensitive drum11as an image bearing member, a transfer roller9as a transfer device, and the like.

Inside the apparatus main assembly B1of the image forming apparatus B, the image forming portion Q, a cassette6and a fixing device10are provided. The image forming portion Q includes a cleaner unit24including the photosensitive drum11, a developer accommodating unit25, an exposure device8, and the transfer roller9. Of these members, a cartridge A is constituted principally by the cleaner unit24and the developer accommodating unit25. Further, in a conveying path of a sheet S, members consisting of the cassette6, the transfer roller9, the fixing device10, a discharging roller pair1and a discharge portion3where the discharged sheet S is to be stacked, are provided in this order.

For image formation, in synchronism with the conveyance of the sheet S from the cassette6, the exposure device8selectively exposes the surface of the photosensitive drum11to light, so that an electrostatic latent image is formed on the surface of the photosensitive drum11. Thereafter, the developer accommodated in a developer bag16is carried in a thin layer on the surface of a developing roller13by a developing blade15. Then, a developing bias is applied to the developing roller13as a developer carrying member, so that depending on the electrostatic latent image, the developer is supplied from the developing roller13to the surface of the photosensitive drum11.

On the other hand, the sheet S is conveyed from the cassette6to a nip between the photosensitive drum11and the transfer roller9. The developer image formed on the surface of the photosensitive drum11by changing, exposure and development, is transferred onto the sheet S by the transfer roller9supplied with a bias voltage. Then, the sheet S on which the developer image is transferred is conveyed to the fixing device10to fix the developer image thereon, and then is discharged onto the discharge portion3at an upper surface of the apparatus main assembly B1by the discharging roller pair1.

FIG. 2is a sectional view showing a structure of the cartridge A. The cartridge A shown inFIG. 2includes the image bearing member and process means acting on the image bearing member. Examples of the process means may include, e.g., a charging means for electrically charging the surface of the image bearing member, a developing device for forming an image on the surface of the image bearing member, and a cleaning means for removing a developer (containing a toner, a carrier and the like) remaining on the surface of the image bearing member. The cartridge A will be described specifically below.

The cartridge A as the process cartridge includes the cleaner unit24including the photosensitive drum11as the image bearing member, a charging roller12as the charging means, an elastic cleaning blade14as the cleaning means. Further, the cartridge includes the developer accommodating unit25including the developing roller13and a developing blade15which are a developing means, the developer bag16accommodating the developer, and a first frame17and a second frame18which support the developing roller13and the developing blade15. Incidentally, the frame a17and18accommodate a developer accommodating container30and an unsealing member20described later.

Further, the cleaner unit24and the developer accommodating unit25are integrally assembled in the cartridge A and is constituted so as to be detachably mountable to the apparatus main assembly B1(FIG. 1). In this embodiment, the developer accommodating unit25includes the developing roller13and the developing blade15but may also have a constitution (not shown) in which the developing roller13and the developing blade15are not included.

FIG. 3is a perspective view showing structures of the developing bag16, the sealing member19and the unsealing member20. As shown inFIG. 3, the developer accommodating container30includes the developer bag16as a flexible container and includes the sealing member19. The developer bag16the developer inside the bag and specifically has the following constitution. The developer bag16includes a discharging portion16b. The discharging portion16bincludes a plurality of openings16c, for permitting discharge of the developer, arranged in an arrow F direction substantially perpendicular to an arrow C direction in which unsealing advances, and includes a plurality of connecting portions19g. The openings16copen, and the connecting portions16gestablishes a relationship with the openings such that the connecting portions16gare interposed between the openings16cto connect the openings16c.

Further, the sealing member19is mounted on the developing bag16in order to seal the openings16c, and exposes the openings16cwhen being peeled from the developing bag16. Specifically, the sealing member19is applied onto the discharging portion16bto seal the openings16cso as to prevent the developer inside the developing bag16from leaking out of the developer bag16. The sealing member19is formed in a sheet shape.

Further, the unsealing member20is mounted on the sealing member19at an end portion of the sealing member19. When the unsealing member20is rotated in the arrow C direction, the sealing member19is rotated to open the openings16cof the developer bag16. Thus, the unsealing member20unseals the openings16cby operating the sealing member19to peel the sealing member19from the developing bag16. As a result, the developer comes out of the developer bag16.

FIG. 4is a sectional view showing a structure of the developer accommodating unit25. As shown inFIG. 4, the developer accommodating unit25includes the developing bag16, and the sealing member19is mounted on the developing bag16. The sealing member19includes a sealing portion19a, a holding portion19band a connecting portion19c. The sealing portion19ais defined in an end portion side of the sealing member19and covers and seals the openings16c(FIG. 3) of the discharging portion16b. The holding portion19bis defined in another end side of the sealing member19and is held by the unsealing member20. The connecting portion19cas a developer passing portion connects the sealing portion19aand the holding portion19band is formed so that the developer is passable. These portions of the sealing member19are arranged from a base end side to a leading end side in the order of the holding portion19b, the connecting portion19cand the sealing portion19a.

The connecting portion19cis provided with a plurality of holes19n(FIG. 6). The sealing member19is folded once from the sealing portion19ato the holding portion19b. The sealing portion19ain the leading end side of the sealing member19is mounted on the discharging portion16bby a first welding portion16eand a second welding portion16d. The holding portion19bin the base end side of the sealing member19is mounted on the unsealing member20by a third welding portion20c.

The unsealing member20is rotatably supported about its shaft by the frames17and18. The unsealing member20corresponds to a shaft rotatably supported by the first frame17and includes a first fixing side20xand a second fixing side20y. Each of the first fixing side20xand the second fixing side20yis constituted by a flat surface substantially parallel to an axis of the unsealing member20. In the first fixing side20x, the holding portion19bof the sealing member19is fixed, and in the second fixing side20y, a holding portion21bof an urging member21in a base end side is fixed. The holding portion21bof the urging member21is fixed on the second fixing side20yby a fourth welding portion20d, and the urging member21urges the developer bag16in its leading (free) end side by being rotated. The urging member21is disposed inside the frames17and18, and urges the developing bag16to deform the developing bag16.

Next, a fixing state of the inside members of the developer accommodating unit25will be described. For fixing, (heat) welding, ultrasonic welding, bonding, pseudo-bonding or the like is employed. The sealing member19is fixed on the discharging portion16bat the sealing portion19ain the leading end side in a peelable manner, thus sealing the openings16c. The sealing member19is fixed on the unsealing member20at the holding portion19bin the base end side.

As the fixing means, in addition to the welding, the ultrasonic welding, the bonding and the pseudo-bonding, it is possible to use clamping by grip-shaped portions, hanging by holes and projections, and the like.

The developing bag16, the sealing member19and the unsealing member20are accommodated in the first frame17and are also covered with the second frame18. Then, the first frame17and the second frame18are bonded by the welding, the bonding or the like, so that the respective members are accommodated inside the developer accommodating unit25. The developer bag16is provided with fixing holes16xand16y.

A fixing portion116xis fixed to the first frame17through the fixing holes16x. A fixing portion116yfor connecting the first frame17and the second frame18is fixed to the first frame17and the second frame18through the holes16y. The fixing portions116xand116yare fixed to at least one of the first and second frames17and18by using, e.g., a double-side tape, a wedge-shaped member, a hook-shaped member, the welding, the ultrasonic welding or the bonding. Incidentally, the developing bag16is provided with the fixing holes16xand16yin a flat side (surface) substantially parallel to the axis of the unsealing member20.

Next, details and a mutual relationship of the respective members of the developing bag16will be described with reference to the drawings3,4and5. The developing bag16includes the discharging portion16band is clogged by the sealing member19as described above. Other sides of the developing bag16constitutes a folding-back portion of the bag material or a bag-shaped portion by firmly bonding bag materials to each other by using the welding, the ultrasonic welding, the bonding or the like. In order to realize the unsealing by the above-described constitution, there is a need to always peel the discharging portion16bfirst, and therefore it is essential that at all of bonding portions of the developing bag16, strength, i.e., a peeling force of each bonding portion between the sealing member19and the developer bag16is weakest. This is true for other portions. With respect to a fixing force between the sealing member19and the unsealing member20, a fixing force between the developer bag16and the first frame17or the second frame18, or the like force, it is essential that the above-described peeling force is weakest.

On the other hand, the developer accommodating unit25functionally accommodates the toner therein, and therefore from the viewpoint of a sealing property, a larger peeling force to the possible extent is advantageous. This is because when the peeling force is large, there is a high possibility that a status in which the openings are unsealed in a state other than an intended state (in which the developer accommodating unit25is set in the image forming apparatus B) in the case where an unexpected force (e.g., an impact force during drop) can be avoided. From the above, the peeling force is required to be set at a desired value.

A method of setting the peeling force at the desired value will be described. In this embodiment, in order to set the peeling force at the desired value (a minimum force within a range in which the toner sealing property can be maintained), two methods are principally employed.

In a first method, a laminate material having a special sealant layer which exhibits an easy peeling property (peeling strength of about 3N/15 mm in testing methods for heat sealed flexible packages according to JIS-Z0238) is applied. Further, the first method is a method in which the easy peeling property is exhibited at the peeling portion by using, as the material (member) for the developer bag16, a sheet material (of, e.g., polyethylene or polypropylene) which is weldable with the special sealant layer and which has flexibility. By changing a combination of formulation of the special sealant layer with the material to be bonded, the peeling force can be reduced.

A second method is a method in which as shown inFIGS. 4,5and6, the discharging portion16bof the developer bag16is placed in a state in which the sealing member19is folded back with respect to an unsealing direction (arrow E direction). For example, in the state ofFIG. 4, the unsealing member20is rotated in the rotational direction (arrow C direction), so that the sealing member19is pulled in a pulling direction (arrow D direction) by the unsealing member20. As a result, the developer bag16and the sealing member19establish a positional relationship, as shown inFIG. 4, enabling inclined peeling (peeling at 90 degrees to 180 degrees). It has been conventionally known that the peeling force necessary to separate the both members can be reduced by establishing the inclined peeling positional relationship. Therefore, as described above, the discharging portion16bis placed in the state in which the sealing member19is folded back with respect to the unsealing direction (arrow E direction), so that the peeling force can be reduced.

Next, an effect obtained by employing the constitution in this embodiment will be described. As described above, by appropriately shaping the bonding portions between the developer bag16and the sealing member19and by using the laminate material having the special sealant layer which exhibits the easy peeling property, it is possible to unseal the openings of the developer bag16with a small force (the peeling force of about 3N/15 mm at the portion to be unsealed).

FIG. 5is a sectional view showing a structure of the developer accommodating unit25. While referring toFIG. 5, structures of the unsealing member20, the sealing member19and the urging member21will be specifically described. As shown inFIG. 5, the unsealing member20is formed in a substantially rectangular (polygonal) shape in cross section. The urging member21has a stirring function for stirring the developer discharged from the developer bag16after the discharging portion16bis unsealed (as specifically described later) and has a conveying function for conveying the developer toward the developing roller13.

FIG. 6is an enlarged perspective view showing a structure of the sealing member19after being disposed in the developer accommodating unit25, and corresponds to a schematic view as seen from an arrow G direction indicated inFIG. 4. As shown inFIG. 6, the sealing member19includes the sealing portion19afor covering the openings16cof the developer bag16and a peripheral portion16fof the connecting portion16g. Further, although being not illustrated inFIG. 6, as described above, the sealing member19includes the holding portion19bfixed on the unsealing member20in the first fixing side20x. Further, as shown inFIG. 6, the sealing member19includes the connecting portion19cfor connecting the sealing portion19aand the holding portion19b.

The sealing portion19ais welded at the peripheral portion16fof the connecting portion19cconnecting the openings16c, thus sealing the openings16c. Specifically, the peripheral portion16fof the openings16cis sealed by the first welding portion16d, the second welding portion16eand a widthwise welding portion16p. The first welding portion16dis welded at the peripheral portion16fin the base end side of the sealing portion16a. The second welding portion16eis welded at the peripheral portion16fin the leading end side of the sealing portion16a. The widthwise welding portion16pis welded at the peripheral portion16fso as to connect the first welding portion16dand the second welding portion16eat each of longitudinal end portions of the openings16c. Incidentally, as shown inFIG. 6, the connecting portion19cincludes a continuous member19c1continuous between the sealing portion19aand the holding portion19band is provided with a plurality of holes19, formed on the continuous member19a, for permitting passing of the developer therethrough.

FIG. 7is an enlarged plan view showing a structure of the sealing member19before being disposed in the developer accommodating unit25. As shown inFIG. 7, the connecting portion19cis provided with the plurality of holes19n. The holes19nfunction as a developer passing portion through which the developer is further passed when the developer is discharged from the openings16cof the discharging portion16b. When the connecting portion19cis provided with the plurality of holes19n, a degree of prevention of discharge of the developer by the connecting portion19cis alleviated (as will be specifically described later). The holes19nmay desirably be a circular shape so as not to cause stress concentration since the connecting portion19cis pulled during unsealing or drop. In this embodiment, the holes19nare not illustrated in the figures other thanFIGS. 6,7and11.

FIG. 8is a sectional view showing a structure of the developer accommodating unit25. While principally referring toFIG. 8in combination withFIGS. 4 and 5, an unseal opening of the developer bag16will be described.

When the unsealing member20is rotated in the arrow C direction, the sealing member19is pulled in an arrow D direction (FIG. 4). Then, when the unsealing member20is further rotated in the arrow C direction, the sealing member19is peeled from the first welding portion16d(FIG. 5). Then, when the unsealing member20is further rotated in the arrow C direction, the sealing member19is peeled from the second welding portion16e, and as a result, the discharging portion16bis unsealed (FIG. 8).

FIG. 9is a sectional view showing a structure of the developer accommodating unit25. While referring toFIG. 9, a step of discharging the developer from the developer bag16will be described. As shown inFIG. 9, when the unsealing member20is rotated further in the arrow C direction after the discharging portion16bis unsealed, the urging member21fixed on the unsealing member20is rotated. By this opening, the urging member21urges the developer bag16in an arrow J direction while deforming the developer bag16. In this way, when the developer bag16is urged by the urging member21, an inside volume of the developer bag16is reduced, and thus the inside developer is pushed out, so that the developer is discharged in an arrow I direction from the discharging portion16b.

FIG. 10is a sectional view showing a structure of the developer accommodating unit25. As shown inFIG. 10, when the unsealing member20is rotated further in the arrow C direction, the urging member21is separated from the developer bag16. At this time, the developer bag16has elasticity and therefore the developer bag16is expanded so as to be restored to a state before being urged by the urging member21. As described above, also by the rotation of the urging member21, the urging member21urges the developer bag16to discharge the developer from the openings16c. When such a cycle is repeated, the developer inside the developer bag16is stably discharged (in the arrow L direction). In addition, the discharged developer includes a component to be discharged by its self-weight from the openings16c, a component to be discharged by vibration when the urging member21is separated from the developer bag16, a component to be discharged by flow of the developer inside the developer bag16due to deformation of the developer bag16(in the arrow L direction), and the like component.

As described above, when the developer is discharged, it is desirable that there is no member in the neighborhood of the openings16c. This is because powder such as the developer has a flowing speed which is slow when it passes through a narrow range and therefore a discharging speed is lowered.

FIG. 11is a sectional view showing a structure of the developer accommodating unit25. As shown inFIG. 11, the holes19nprovided in the sealing member19are set and disposed, when the unsealing member20is rotated, so as to pass through positions where they oppose the openings16c. To put it briefly, there are many phases where the sealing member19is located in the neighborhood of front portions of the openings16cof the developer bag16with rotation of the unsealing member20. In such a case, when the sealing member19is provided with the openings19n, more discharging paths of the developer are ensured, so that the developer is discharged efficiently in an arrow M direction. At this time, it is desirable that the openings16cof the discharging portion16band the holes19nof the connecting portion19coppose each other to ensure developer discharging phases with reliability. Further, the sealing member19may also function as the urging member21, and in that case, when the unsealing member20is rotated, the developer bag16deforms the sealing member19.

As described above, the unsealing of the discharging portion16bof the developer bag16is enabled by only pulling the sealing member19in one direction (arrow D direction) by the unsealing member20, so that the openings16cof the developer bag16is stably unsealed with reliability. Further, the cartridge A is pulled in a widthwise direction perpendicular to a longitudinal direction, so that the developer bag16can be unsealed, and therefore a peeling distance which is about two times a longitudinal distance of a conventional cartridge can be considerably reduced. The sealing member19after being unsealed is fixed on the unsealing member20, so that it is possible to unseal the developer bag16without generating a waste member from the process cartridge.

Further, by the urging member21and the holes19n, the discharge of the developer from the inside of the developer bag16is quickly made with reliability, thus leading to a reduction in time required from insertion to a printable state of the process cartridge. Further, the developer bag16has a bag shape, so that the developer can be treated as a unit, and therefore a developer filling step can be separated from a process cartridge assembling step.

FIG. 12is an enlarged sectional view for illustrating a structure of the sealing member19, the developer bag16and the first frame17after being disposed in a developer accommodating unit25in this embodiment. Constituent elements (members), of the developer accommodating unit25in this embodiment, having the same constitutions and effects as those of the developer accommodating unit25in Embodiment 1 are represented by the same reference numerals or symbols and will be appropriately omitted from description (similarly applied in Embodiments 3 and 4 appearing hereinafter). Also in this embodiment, the constituent elements can be applied to the developer accommodating unit25and the image forming apparatus B similar to those in Embodiment 1, and therefore description of the developer accommodating unit25and the image forming apparatus B will be omitted (similarly applied in Embodiments 3 and 4). A characteristic feature in the constitution in this embodiment is as follows.

The developer bag16has flexibility and does not have a completely defined shape, so that there is a need to ensure a clearance where the developer bag16is assembled with the first frame17. For that reason, at an end portion of the unsealing member20with respect to a rotational axis direction, a space (indicated by an arrow N) where the developer bag16is assembled with the first frame17is ensured. With respect to the discharge of the developer after the sealing portion19ais peeled, it is desirable that a discharging amount of the developer at the end portion is larger than at a central portion with respect to the rotational axis direction.

FIG. 13is an enlarged plan view showing a structure of a sealing member319before being provided in the developer accommodating unit in this embodiment.FIG. 13corresponds to a schematic view as seen from the arrow G direction in a state in which the sealing member319disposed in the developer accommodating unit is extended. The structure of the sealing member319will be specifically described. Constitutions of a welding portion where the sealing member319is welded on the developer bag16and a fixing portion where the sealing member319is fixed on the unsealing member20are the same as those in the case of Embodiment 1. The connecting portion19cincludes a plurality of holes19n. Of the holes19n, holes19n2in an end portion side of the continuous member19c1with respect to an axial direction R of the unsealing member20are formed in a larger size than that of holes19n1in a central portion side of the continuous member19c1with respect to the axial direction R of the unsealing member20. For that reason, the holes19nconstitute portions through which the developer passes when the developer is discharged from the openings16cof the discharging portion16b, so that a developer discharging amount is larger at the end portion than at the central portion with respect to the rotational axis direction of the unsealing member20. In this embodiment, a shape of the holes19n2is an elliptical shape elongated in the rotational direction of the unsealing member20but may also be not limited to the elliptical shape.

It would be also considered that all the holes19nare formed in a larger size to the possible extent, but a range in which the size can be increased is limited by a balance with the strength (stiffness). The size of each of the openings19nat the central portion and end portions of the unsealing member20with respect to the rotational axis direction may only be required to be determined within the range.

By the constitution described above, in addition to the effect in Embodiment 1, an insufficient feeding force to the end portions can be compensated by ensuring the assembling space, so that also the developer discharge is quickly performed with reliability. Accordingly, the time required from the insertion to the printable state of the process cartridge can be reduced.

FIG. 4is an enlarged plan view showing a structure of a sealing member419before being provided in a developer accommodating unit in this embodiment. Other than the constitutions described above, it is possible to employ a constitution in which the developer passing portion is formed by changing a shape of the connecting portion19cof the sealing member419so that the developer is discharged in a larger amount at the end portion with respect to the axial direction R of the unsealing member20. For example, as shown inFIG. 14, the continuous member19c1may also be formed in a smaller size than the sealing portion19aand the holding portion19bwith respect to the axial direction R of the unsealing member20. To put it briefly, the connecting portion19chas a cut-away portion in a curved shape at end portions with respect to the rotational axis direction thereof. This shape may also be applied to the constitutions in Embodiments 1 to 3.

According to the constitution in Embodiment 1, there is no effort of the user to remove the unsealing member, so that the developer discharging efficiency from the developer bag16in which the developer is accommodated. Particularly, while using the sealing member19for improving flowability of the developer, it is possible to suppress a phenomenon that flow of the developer which flows from the openings16cis prevented by the sealing member19after the unsealing member20is operated to release the sealing of the openings16cby the sealing member19. Further, in this way, by employing the constitution in which the release of the sealing by the sealing member19can be effected by the inside member, there is no need for the user to pull out the sealing member19of the cartridge A, so that the cartridge A can be replaced simply. This is true for also the constitutions in Embodiments 2 and 3.

According to the constitution in Embodiment 3, the holes19n2of the continuous member19c1are formed in the larger size at the end portion than at the central portion. As a result, the developer can pass through the holes19n1in the central side and concurrently can pass through the holes19n2in the end side at a higher efficiency than that in the central side.

According to the constitution in Embodiment 4, the holes19n2of the continuous member19c1are formed in the small size than the surface and the holding portion19bwith respect to the axial direction R of the unsealing member20. As a result, the developer can pass through the holes19nand concurrently can pass through a portion outside a cut-away portion419X of the continuous member19c1with respect to the axial direction R of the unsealing member20.

According to the present invention, there is no effort of the user to remove the sealing member, and the developer discharging efficiency from the flexible container in which the developer is accommodated is improved.

This application claims priority from Japanese Patent Application No. 115868/2012 filed May 21, 2012, which is hereby incorporated by reference.