Abstract:
A method, for recycling an ink cartridge used for a recording apparatus, comprises the steps of: discharging residual ink from an ink cartridge wherein a porous member is retained for the absorption of ink; using a cleansing fluid to clean the porous member; discharging the cleansing fluid from the porous member; and impregnating the porous member with ink.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a recycling technique of an ink cartridge for an ink-jet recording apparatus, in which the resupply of ink is effected by the replacement of the cartridge. The present invention is particularly applicable, but not limited to, an ink-jet recording apparatus of a type in which an ink-jet recording head and an ink cartridge are mounted on a carriage. 
     An ink-jet recording apparatus is known in which an ink container is attached to a carriage having an ink-jet recording head mounted thereon. In order to prevent printing failures associated with water head pressure change and air bubble generation due to agitation of ink by the carriage movement, it is preferable to accommodate a porous member at least in an ink supply port of the ink container, as disclosed in European Patent Publication No. 581531. 
     This arrangement can solve the above-mentioned problems linked with the ink agitation since the ink is supplied to the recording head via the porous member. 
     The recycling of ink cartridges is a desirable objective, and is in consonance with the current trend of effectively conserving resources and reducing the amount of pharmaceutical agents that are discharged to the environment. Japanese Unexamined Patent Publication No. Hei 7-60979 discloses an ink cartridge recycling apparatus having an annular member provided with a rotatable ink chamber. An ink cartridge is mounted on the annular member so that the ink supply port faces outward while an ink supply tube is connected to a lid side of the ink cartridge, and then the annular member is rotated in that state. 
     This apparatus makes it possible to fill new ink into a collected ink cartridge while discharging the remaining old ink from the collected ink cartridge using centrifugal force produced by the rotation of the annular member. 
     This apparatus, however, suffers from a problem in that the size of the apparatus is large because centrifugal force must be employed. Further, ink may not be completely discharged by the centrifugal force because of strong capillary attraction originating in the porous member contained in an ink cartridge, and/or because of solidification or increased viscosity of the ink. Consequently, refilled new ink is mixed with old ink to lower printing quality, and this is a serious problem, in particular, in case of ink cartridges for color printing. 
     It is conceivable to remove the porous member from the cartridge and then clean the cartridge sufficiently. The disassembly and the reassembly of cartridge is, however, required to increase the cost. 
     SUMMARY OF THE INVENTION 
     Therefor, an objective of the present invention is to provide a method for recycling an ink cartridge, which does not require the disassembly of an ink cartridge and which can provide a refilled ink cartridge ensuring high quality printing. 
     In the method of the present invention, a porous member in an ink cartridge is cleansed by cleansing fluid. Further, the cleansing fluid is discharged from the porous member. Therefore, new ink is neither mixed with residual ink nor cleansing fluid. The ink cartridge, after recycling, can provide the same quality as a brand-new cartridge. 
     Preferably, a method for recycling an ink cartridge for a recording apparatus according to the present invention comprising the steps of: 
     discharging residual ink from an ink cartridge in which a porous member for ink absorption is accommodated; 
     cleansing the porous member using cleansing fluid; 
     discharging the cleansing fluid from the porous member; and 
     impregnating the porous member with ink. 
     Therefore, refilling of ink can be carried out with the porous member accommodated in the ink cartridge and without disassembly of the ink cartridge. The cleansing fluid can completely remove any residual ink. Thus, an ink cartridge can be recycled at a low cost, and the same quality can be provided as that provided by a brand new one, without any contamination. 
     The present disclosure relates to the subject matter contained in Japanese patent application Nos. Hei. 10-364143 (filed on Dec. 22, 1998), and Hei. 11-358714 (filed on Dec. 17, 1999), all of which are expressly incorporated herein by reference in their entireties. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of an ink cartridge according to one embodiment of the present invention for which the recycling method of the present invention can be employed. 
     FIG. 2 is a cross-sectional view of the structure of the ink cartridge. 
     FIG. 3 is a top view of the structure of a lid of the ink cartridge. 
     FIG. 4 is a diagram showing an example of a work table that is used at an ink discharge step in an ink cartridge recycling process. 
     FIG. 5 a cross-sectional view for explaining a step during which residual ink is discharged. 
     FIG. 6 is a diagram showing the structure of an ink filling device. 
     FIG. 7 is a diagram showing the first half of a packaging step for a recycled ink cartridge. 
     FIG. 8 is a diagram showing the second half of the packaging step for the recycled ink cartridge. 
     FIG. 9 is a diagram showing another example of a work table used in the cartridge recycling process. 
     FIG. 10 is a diagram showing the residual ink discharging step using the work table. 
     FIG. 11 is a diagram showing an ink cartridge according to another embodiment for which the present invention can be applied. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1 and 2 are diagrams showing an ink cartridge, according to one embodiment of the present invention, for which a manufacturing method of this invention is applied. A container  1 , having a substantially rectangular, parallelpiped shape, is formed by the injection of a polymer material, with the open side being slightly larger than the opposite side. The container  1  has walls  2  defining a plurality of ink chambers  3 . In each of the ink chamber  3 , a porous member  4 , made of a flexible material that is appropriate for ink absorption is accommodated in a compressed state. Formed at the bottom end of each chamber  3 , is an ink supply port  5  which receives an ink supply needle or ink supply tube of a recording head. An opening  6  is sealingly closed by a lid  9  having ink introduction holes  7  and air communication holes  8 . 
     A projecting portion  10  is provided for each ink chamber  3  to compress the porous member  4  in the vicinity of the ink supply port  5 . The upper end of the projection portion  10  is formed into a recessed portion  12  that defines a chamber  11  having a predetermined opening area. A through-hole  13  extends from the chamber  11  to the ink supply port  5 . A packing  16  is fitted on the outer end portion of the through-hole  13 . The packing  16  is adapted to hermetically engage the ink supply needle or ink supply tube of the recording head. A gas impermeable film  17  is attached to cover the ink supply port  5 . The film  17  is made, for example, of a low density polyethylene film having low moisture permeability, and can be broken upon the ink supply needle is inserted into the ink supply port  5 . Reference numeral  18  in FIGS. 1 and 2 denotes a filter member that is provided to cover the recessed portion  12 . 
     As shown in FIG. 3, meandering grooves  19  are formed in the upper surface of the lid  9 , each of which is communicated at its one end with a corresponding air communication hole  8 . The other end of each meandering groove  19  is extended to the lower side of the lid  9  in FIG. 3. A film  20  is attached to the lid  9  to cover a hatched area. The lower half of the film  20  in FIG. 3 can be peeled off by lifting a tongue piece  20   a.    
     The re-filling method will now be described. 
     The surface of an ink cartridge collected from a user is cleaned, and the films  17  and  20  are peeled off from the ink supply ports  5  and the lid  9 . Then, the ink cartridge is set on a work table  31  in which suction ports  30  are formed as shown in FIG. 4 to engage the ink supply ports  5 . 
     As shown in FIG. 5, negative pressure is applied to the ink supply ports  5  by an ink suction device that communicates with the suction ports  30 , so that ink remaining in the porous members  4 , etc. is removed by suction. 
     Hollow needles  32 , which communicate with a device for supplying a cleansing fluid that is, for example, refined water, a solvent, a constituent of ink, are abutted upon or inserted into the ink introduction holes  7  and the air communication holes  8  in the lid  9  to introduce the cleansing fluid of an amount required to impregnate the porous members  4 , preferably 1 to 15 times of the amount, more preferably 3 times or greater of the amount. As a result, the cleansing fluid flowing from the top of the cartridge permeates the porous members  4 , and then flows out of the ink supply ports  5  to the suction ports  30  while diluting and dispersing the residual ink. 
     After the cleansing step ends, the cleansing fluid is discharged from the porous members  4 . The cleansing fluid discharge step is preferably carried out such that negative pressure is applied to the ink supply ports  5  so that the cleansing fluid is forcibly extracted by suction. 
     More preferably, each of the cleansing step and the cleansing fluid discharge step is divided into plural sub-steps, so that the cleansing substeps and the cleansing fluid discharge sub-steps are carried out alternately. In other words, a required amount of the cleansing fluid to be introduced during the cleansing step is divided, so that the cleansing step is carried out plural times each followed by a cleansing fluid discharge step using suction. Further, it is also preferable and effective to vary the amount of cleansing fluid and the inflow rate of the cleansing fluid depending on the number of times the cleansing has been carried out, i.e., the degree of cleansing achieved. Moreover, an amount or flow rate of the cleansing fluid supplied during one cleansing sub-step may be different from an amount or flow rate supplied during another cleansing sub-step. 
     Thereafter, the cleansing fluid retained by capillary attraction in the porous members  4  is removed by natural drying, ventilation drying or decompression drying. That is, the ink cartridge is maintained at room temperature, dry air is introduced via the ink introduction holes  7  and the air communication holes  8  of the lid  9 , or via the ink supply ports  5 , the ink cartridge is placed in a decompression chamber, etc. 
     More preferably, the cleansing fluid retained by capillary attraction is volatilized by heating the ink cartridge for a predetermined period of time, e.g., for one day, at a temperature, e.g., 60° C., at which no deterioration of the porous members  4  occurs. This makes it possible to easily and surely remove the cleansing fluid from the porous members  4  without any great change to the manufacturing line. Thus, productivity can be improved. 
     Still more preferably, after the cleansing fluid has been discharged from the porous members  4 , the ink cartridge is heated for approximately 24 hours at a temperature of approximately 60° C. Then, the ink cartridge is placed in a vacuum chamber for vacuum drying until the cleansing fluid is reduced to approximately 0.4 g per 80 g of the porous member  4 . 
     After the cleansing fluid has been discharged, the ink supply ports  5  of the ink cartridge are sealed by attaching to them gas-impermeable films  17 , respectively. It is also preferable that the packing  16  be replaced with new one at this time. The replacement of the packing  16  that has been thermally deteriorated during the cleansing step or the cleaning fluid discharge step with new one improves the reliability or quality of the recycled product. 
     As shown in FIG. 6, an introduction tube  34  that communicates with an ink supply unit  33  is inserted through the ink introduction hole  7  into the porous member  4 . A discharge tube  35 , which communicates with a vacuum pump, is connected to the air communication hole  8 . While removing air from the upper space of the cartridge, a predetermined amount of degassed ink is introduced into the porous member  4  from a metering pipe  42  to which ink from a tank  41  has been preliminarily supplied via a degassing unit  40 . 
     In a case where an ink cartridge is recycled to an ink cartridge having the same specifications as the former ink cartridge, it is preferable that the density of effective ink constituent elements, such as pigments, dyes, surface-active agents or moisture solvents, be slightly reduced. That is, since the porous member of the ink cartridge has been so impregnated with the effective constituent elements of the initially filled ink that those elements can no further be dissolved, the effective constituent elements of the ink used for re-filling will not be absorbed by the porous member  4 , and the density of the ink will not be reduced. 
     Subsequently to filling the ink of a predetermined amount,the gas-impermeable film  20  is attached to the surface of the lid  9  to seal the ink introduction holes  7 , the air communication holes  8 , and the grooves  19 . 
     Then, as shown in FIG. 7, the tongue piece  20   a  of the film  20  is folded down and the container  1  is inserted into a bag  35  formed of an air-impermeable film. 
     An opening  35   a  is thereafter closed by heat sealing in a reduced-pressure environment. As shown in FIG. 8, the bag  35  is then stored in a case  36  on which the trademark of the recycling company is displayed. In this fashion, the production of the product is completed. 
     If the suction ports are formed as hollow needles  50  as shown in FIG. 9, then, as is shown in FIG. 10, the hollow needles  50  can be inserted into the ink supply ports  5  in the same manner as when the ink cartridge is mounted on a recording head, and the cleansing fluid can be drawn out. 
     In the above description, an ink cartridge in which all ink is impregnated in the porous members  4  has been explained. The same effects can be obtained by applying the recycling process of the present invention to an ink cartridge shown in FIG. 11, in which a form chamber  3  is divided by a wall  1   b  having a communication hole  1   a  to have an ink chamber  37 . 
     In the above description, the film  17  is attached to the ink supply port  5  to seal the ink supply port  5 . The present invention is not restricted thereto or thereby. For example, the packing member  16  per se may have the sealing function for the ink supply port  5 , or an integrally formed member having both the sealing function and the packing function may be used. In this case, it is preferable to detach the packing member  16  or the integrally formed member from the ink supply port  5  prior to the negative pressure applying step, and to attach the packing member  16  or the integrally formed member to the ink supply port  5  (or to attach a new packing member  16  or a new integrally formed member to the ink supply port  5 ) prior to the ink refilling step.