Patent Publication Number: US-8995869-B2

Title: Image forming apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from Korean Patent Application No. 10-2012-0004972, filed on Jan. 16, 2012, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     1. Field 
     Devices and methods consistent with the present general inventive concept provided herein relate to an image forming apparatus, and more specifically, to an image forming apparatus which reduces an amount of discharged micro-particles. 
     2. Description of the Related Art 
     An image forming apparatus adopting electrophotographic printing method such as printer, copier, and/or facsimile generally includes a developing module and a fixing module. The developing module develops a toner image on a printing medium, and the fixing module fixes the toner image into the printing medium. 
     When fixing the image, the printing medium is subject to heat and pressure from the fixing module, and the toner of the toner image on the printing medium may produce undesirable gases. 
     Particularly, excessive amounts of nano-scaled fine particles (FP) and ultrafine particles (UFP), which are extremely small, may be discharged externally from the image forming apparatus, and may be inadvertently introduced to humans. 
     SUMMARY 
     Exemplary embodiments of the present inventive concept overcome the above disadvantages and other disadvantages not described above. Also, the present general inventive concept is not required to overcome the disadvantages described above, and an exemplary embodiment of the present general inventive concept may not overcome any of the problems described above. 
     Additional features and utilities of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, and/or may be learned by practice of the general inventive concept. 
     According to one exemplary embodiment, a technical objective is to provide an image forming apparatus which may reduce an amount of discharged fine particles (FP) and ultrafine particles (UFP). 
     In one exemplary embodiment, an image forming apparatus adopting an electrophotographic printing method is provided, which may include a developing module which develops a toner image on a printing medium, a fixing module which fixes the toner image onto the printing medium, and a toner neutralization module arranged on a travel path of the printing medium between the developing module and the fixing module to electrically neutralize the toner image on the printing medium. 
     The toner neutralization module may include an electric charge elimination member which is arranged in contact with the printing medium, is connected to the ground, and which has conductivity. 
     The toner neutralization module may additionally include a power source to apply voltage to the electric charge elimination member. 
     The power source may include a direct current (DC) power source, and is connected to the electric charge elimination member. 
     The electric charge elimination member may have a plate-like shape, with one surface being in contact with the printing medium. 
     The electric charge elimination member may include at least one pointed protrusion formed on one surface to be in contact with the printing medium. 
     The toner neutralization module may include an ion spray member which provides ions onto the printing medium to electrically neutralize the toner image. 
     The image forming apparatus may additionally include an electromagnetic filter module which filters harmful particles generated by the fixing module using electromagnetic force. 
     The harmful particles may include fine particles (FP) and ultrafine particles (UFP). 
     The image forming apparatus may include a paper ejection outlet through which the printing medium is discharged from the image forming apparatus, and the electromagnetic filter module may be arranged on a travel path of the printing medium between the fixing module and the paper ejection outlet. 
     The electromagnetic filter module may be installed adjacent to the paper ejection outlet. 
     The image forming apparatus may include at least one air outlet to discharge air in the image forming apparatus to outside, and the electromagnetic filter may be installed adjacent to the air outlet. 
     The electromagnetic filter module may include a magnetic field forming member to form a magnetic field therearound. 
     The magnetic field forming member may include a permanent magnet and/or an electromagnet. 
     The electromagnetic filter module may include an electric field forming member to form an electric field therearound. 
     The electric field forming member may include a conductor through which electric current flows. 
     The electromagnetic filter module may include a magnetic field forming member to form a magnetic field therearound, and an electric field forming member to form an electric field therearound. 
     In one exemplary embodiment, an image forming apparatus adopting an electrophotographic printing method may include a developing module which develops a toner image on a printing medium, a fixing module which fixes the toner image onto the printing medium, and an electromagnetic filter module which filters harmful particles generated by the fixing module using electromagnetic force. 
     In one exemplary embodiment, an image forming apparatus adopting electrophotographic printing method may include a developing module which develops a toner image on a printing medium, a fixing module which fixes the toner image onto the printing medium, a toner neutralization module arranged on a travel path of the printing medium between the developing module and the fixing module to electrically neutralize the toner image on the printing medium, and an electromagnetic filter module which filters harmful particles discharged from the image forming apparatus using electromagnetic force. 
     In an exemplary embodiment, an image forming apparatus has at least a developing module and a fixing module that perform an electrophotographic printing method. The image forming apparatus includes a printing system and an harmful material reducing module. The printing system is in electrical communication with a power source and includes at least a developing module that develops a toner image on a printing medium that travels on a travel path to a fixing module that fixes the toner image onto the printing medium. Further, the harmful material reducing module includes at least one of an electric charge eliminating member and an electromagnetic filter module. The electric charge eliminating member is in electrical communication with the power source and is arranged on the travel path of the printing medium between the developing module and the fixing module to neutralize electrified charges of a toner image on the printing medium. The electromagnetic filter module is in electrical communication with the power source and is arranged proximate to a printing medium ejection outlet to attract charged fine particles and ultrafine particles to minimize output of the fine particles and ultrafine particles. 
     The electric charge eliminating member may be one of an electrically conductive material that includes one of a rectangular plate form, a cylindrical shape, and a plate-shaped body with pointed protrusions, and/or may be an ion-spraying member. 
     The electromagnetic filter module may include one of a rectangular plate of a permanent magnet, a cylindrical-shaped magnetic field forming member, an electromagnet that includes a core member and coils, and an electromagnetic field forming member in electrical communication with the power source. 
     In an exemplary embodiment, an image forming apparatus performs an electrophotographic printing method and minimizes output of charged fine particles and ultrafine particles. The image forming apparatus includes a printing system which is in electrical communication with a power source and an harmful material reducing module. The harmful material reducing module includes at least one of an electric charge eliminating member and an electromagnetic filter module. The electric charge eliminating member is in electrical communication with the power source and is arranged on a travel path of a printing medium in the printing system to neutralize electrified charges of a toner image on the printing medium. In addition, the electromagnetic filter module is in electrical communication with the power source and is arranged proximate to a printing medium ejection outlet to attract charged fine particles and ultrafine particles, minimizing output of the fine particles and ultrafine particles. 
     The printing system may include at least a developing module that develops the toner image on the printing medium that travels on the travel path and a fixing module that fixes the toner image onto the printing medium. 
     In an exemplary embodiment, an image forming apparatus includes a filter unit formed with a wall of the image forming apparatus to filter undesired particles traveling along an outlet path. The filter unit may include at least one air ventilation outlet/vent formed in the wall and aligned with the outlet path to receive the undesirable particles therethrough and an electromagnetic filter module disposed adjacent the at least one vent to generate a magnetic field that attracts the undesirable particles traveling toward the vent to the electromagnetic filter module. 
     The electromagnetic filter module may include a surface facing the outlet path such that the undesirable particles adhere to the surface due to an electromagnetic attractive force of the electromagnetic filter module. Further, a ledge may extend parallel with the outlet path and may have a surface facing the outlet path. The electromagnetic filter module may be coupled to the ledge and may face the outlet path through the at least one vent. 
     In addition, the at least one vent may include a plurality of vents, each vent aligned with a respective outlet path to receive undesired particles passing therethrough. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other features and utilities of the present general inventive concept will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  is a schematic cross-section view of an image forming apparatus according to an exemplary embodiment; 
         FIG. 2  is a diagram illustrating a mechanism of producing fine particles and ultrafine particles according to an exemplary embodiment; 
         FIG. 3  is an enlarged view of a surrounding area of the fixing module of  FIG. 1  according to an exemplary embodiment; 
         FIG. 4  is a schematic perspective view of a toner neutralization unit included in the image forming apparatus of  FIG. 1  according to an exemplary embodiment; 
         FIG. 5  is a perspective view of an electric charge eliminating member included in the toner neutralization module of  FIG. 4  according to an exemplary embodiment; 
         FIG. 6  is a perspective view of the electric charge eliminating member included in the toner neutralization module in  FIG. 4  according to another exemplary embodiment; 
         FIG. 7  is a schematic diagram illustrating a toner neutralization module according to an exemplary embodiment; 
         FIG. 8  is a cross-section view of an electromagnetic filter module installed proximate to a paper ejection outlet according to an exemplary embodiment; 
         FIG. 9A  is a perspective view of the electromagnetic filter unit of  FIG. 8  according to an exemplary embodiment; 
         FIG. 9B  is a perspective view of a electromagnetic filter module as an alternative to the electromagnetic filter module of  FIG. 9A , according to an exemplary embodiment; 
         FIG. 10  is a schematic perspective view of the electromagnetic filter module according to a second exemplary embodiment; 
         FIG. 11  is a schematic perspective view of the electromagnetic filter module according to a third exemplary embodiment; 
         FIG. 12  is a schematic cross-section view of the electromagnetic filter module of the image forming apparatus, installed near an air ventilation outlet according to an exemplary embodiment; and 
         FIG. 13  is a block diagram of an image forming apparatus according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
     Reference will now be made in detail to the exemplary embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The exemplary embodiments are described below to explain the present general inventive concept while referring to the figures. 
       FIG. 1  is a schematic cross-section view of an image forming apparatus according to an exemplary embodiment. The image forming apparatus may also be other types of the image-forming apparatuses that adopt the electrophotographic printing method, such as a copy machine or a facsimile. 
     Referring to  FIG. 1 , an image forming apparatus  1  may include a main body  10  and a printing medium supply module  20  which provides the recording medium by a single basis to the main body  10  established below the main body  10 . 
     The main body  10  may include a side casing  11  having a plurality of air ventilation outlets/vents  11   a  and an upper casing  12  having a paper outlet  12   a . The main body  10  may further include a developing module  30 , a transfer module  40 , a fixing module  50 , and a light scanning module  60  in the inner area defined by the casings  11  and  12 . 
     The developing module  30  may include an image holding member  31 , a charge roller  32 , a toner cartridge  33 , a toner supply roller  34 , and a developing roller  35 . The charge roller  32  may charge the image holding member  31  with a specific potential, the toner supply roller  34  may provide the toner of the toner cartridge  33  to the developing roller  35 , and the developing roller  35  may develop the toner image corresponding to the electrostatic latent image on the image holder member  31 . 
     The transfer module  40  may include a transfer roller  41  which is opposed to the image holding member  31  with a transfer nip formed therebetween. When the printing medium passes through the transfer nip between the image holding member  31  and the transfer roller  41 , the toner image on the image holding member  31  is formed on (transferred onto) the printing medium. 
     The fixing module  50  may include a heating member  51  and a pressuring member  52  formed opposite to each other. Referring to  FIG. 1 , the heating member  51  and the pressuring member  52  may be a heating roller and a pressuring roller. The printing medium may be heated and pressed upon passing through the fixing nip between the heating member  51  and the pressuring member  52  so that the toner image is fixed onto the printing medium by the heat and the pressure. 
     The scanning module  60  may form an electrostatic latent image on the surface of the image holding member  31 . For instance, the scanning module  60  may be the laser scanning module (LSU) which emits a laser beam onto the image holding member  31  to form electrostatic latent image. 
     The printing process of the image forming apparatus  1  will be explained below along the travel path (P) of the printing medium. The printing medium in the supply module  20  of the printing medium may be picked up on a single sheet basis and enter the main body  10 . When the printing medium passes through the transfer nip between the image holding member  31  and the transfer roller  41 , the toner image is formed on the surface of the printing medium. When the printing medium passes through the fixing nip between the heating member  51  and the pressuring member  52  of the fixing module  50 , the tone image is fixed by the heat and pressure. After the image is fixed, the printing medium is discharged through the paper ejection outlet  12   a  of the upper casing  12 . 
     Harmful materials may be produced by the image forming apparatus  1  while printing. The harmful materials may be fine particles (FP) and ultrafine particles (UFP). 
     It has been understood that the FP and UFP are produced from materials involved with the toner and the image fixation by the heat applied to fix the image. Accordingly, attempts to reduce the amount of the FP and UFP have focused mostly on developing the toner which may be fixed at a lower temperature. However, this requires that such toner fixable at a lower temperature be developed first, and that the control conditions of the image forming apparatus be re-set based on the newly-developed toner. 
     By conducting several tests on the FP and UFP produced from the image forming apparatus  1 , a mechanism which is different from the already-known mechanism has been shown to produce the FP and UFP. 
     This will be explained below with reference to  FIG. 2 .  FIG. 2  is a diagram illustrating a mechanism of producing fine particles and ultrafine particles according to an exemplary embodiment. 
     The toner is a mixture of various components including the semi-volatile organic compounds (SVOC  202 ). The SVOC  202  of the toner may include wax, pigment, etc. 
     When the toner image develops on the image holding member  31 , some electric charges (e.g., electrons) may be charged on the surface of the image holding member  31 . Referring to  FIG. 2 , the SVOC  204  included in the toner is electrified by the electric charges, and activated. The SVOC  204  electrified/activated by the electrons according to one exemplary embodiment will be described below for convenience of explanation. 
     Referring to  FIG. 2 , the ‘activated’ SVOC  204  contained in the toner image is heated and pressured by the fixing module  50  in the toner image fixing process, and decomposed into the volatile organic compounds (VOC-  206 ). Metal materials  208  such as Fe, Sn, and Ti may also be decomposed from the toner. 
     If the SVOC  202  is not activated by electrons, the SVOC  202  is stable and thus, is hardly decomposable. 
     As the name suggests, the VOC- has a lower vaporization point than the SVOC  202 . In other words, the VOC- evaporates at a lower temperature than the SVOC  202 . As used herein, the ‘vaporization’ includes volatilization and evaporation. Thus, if the air temperature in the fixing module  50  is about 180° C. to 190° C., the VOC- volatilizes to a gaseous state while the SVOC  202  does not. 
     Referring to  FIG. 2 , the VOC- in the gaseous state either agglomerate to each other and/or to the seed material, such as Fe, Sn, and/or Ti, thereby producing the FP and UFP. A considerable amount of FP and/or UFP is electrified with the electrons which originated from the SVOC  202  before decomposition. 
     Considering the producing mechanism of the FP and UFP explained above, attempts to reduce the amount of the FP and UFP may be achieved accordingly to different reducing methods. A first reducing method may include preventing decomposition of the SVOC  202  in the image fixing process by eliminating the electrified charges such as electrons from the toner image before the tone image is fixed. A second reducing method may include directly eliminating the produced FP and UFP. 
     Referring back to  FIG. 1 , the image forming apparatus  1  may include a toner neutralization module  70 A and an electromagnetic filter module  80 A. The toner neutralization module  70 A may apply the above-mentioned first reducing method to eliminate the electrified charges of the toner image. The electromagnetic filter module  80 A may apply the above-mentioned second reducing method to eliminate the produced FP and UFP. However, it is appreciated that modules  70 A and  80 A are not limited to these reducing methods. 
     The toner neutralization module  70 A will be explained below. 
       FIG. 3  is an enlarged view of a surrounding area of the fixing module of  FIG. 1  according to an exemplary embodiment.  FIG. 4  is a schematic perspective view of a toner neutralization module  70 A included in the image forming apparatus  1  of  FIG. 1  according to an exemplary embodiment. Further,  FIG. 5  is a perspective view of an electric charge eliminating member  71  included in the toner neutralization module  70 A of  FIG. 4  according to an exemplary embodiment.  FIG. 6  is a perspective view of the electric charge eliminating member  71  included in the toner neutralization module  70 A in  FIG. 4  according to another exemplary embodiment, and  FIG. 7  is a schematic diagram provided to illustrate a toner neutralization module  70 A according to an exemplary embodiment. 
     Referring to  FIGS. 3 and 4 , the toner neutralization module  70 A may be arranged adjacent to the fixing module  50 . In at least one exemplary embodiment, the toner neutralization module  70 A may be arranged on the travel path (P) of the printing medium between the developing module  30  and the fixing module  50  as illustrated in  FIG. 1 . 
     As shown in  FIG. 4 , the toner neutralization module  70 A may include an electric charge eliminating member  71  and a power source  77 . 
     The electric charge eliminating member  71  may include conductive materials, including, but not limited to metal materials and may take a rectangular plate form, for example. However, the electric charge eliminating member  71  may include different shapes, as discussed further below. 
     The electric charge eliminating member  71  may be arranged on the travel path P of the printing medium between the developing module  30  and fixing module  50 . An upper face  71   c  of the electric charge eliminating member  71  may contact a lower face of the printing medium M. For example, one end  71   a  of the electric charge eliminating member  71  may be connected to a ground source  75  through an electric wire  76 . The other end  71   b  of the electric charge eliminating member  71  may be connected to the power source  77  through an electric wire  78 . 
     The power source  77  includes, but is not limited to, direct current (DC). A positive pole of the power source  77  may be connected to the electric charge eliminating member  71  via the electric wire  78 . In at least one exemplary embodiment, the power source may be excluded. However, if the power source  77  providing the voltage of the electric charge eliminating member  71  is included, the performance of the electric charge eliminating member  71  to eliminate the charges may be further enhanced. Meanwhile, the negative pole of the power source  77  is connected to the electric charge eliminating member  71 . Accordingly, the electric charge eliminating member  71  may eliminate the positive charges on the printing medium. 
     The printing medium M with the toner image formed thereon contacts the upper face  71   c  of the electric charge eliminating member  71  in the toner neutralization module  70 A before moving into the fixing module  50 . The charges (i.e., electrons in this exemplary embodiment) electrified to the toner image exit to the ground source  75  through the electric charge eliminating member  71 . Thus, the electrified/activated SVOC  204  included in the toner image may also be eliminated. For example, when the printing medium M contacts the electric charge eliminating member  71 , the toner image on the printing medium M is neutralized electrically and the electrified/activated SVOC  204  in the toner image is also neutralized, i.e., the electrical charge of the SVOC  204  is removed. Accordingly, the amount of the electrified/activated SVOC  204  is reduced greatly. 
     Given the fact that the electrified/activated SVOC  204  greatly contributes to the production of the FP and UFP, the amount of the FP and UFP may be greatly reduced according to an exemplary embodiment described above, because the toner neutralization module  70 A may greatly reduce the amount of the electrically activated SVOC  204  by neutralizing the toner image electrically before image fixing. 
     The form of the electric charge eliminating member  71  included in the toner neutralization module  70 A may not be limited to the plate, and accordingly, other various forms may apply. 
     In one exemplary embodiment, referring to  FIG. 5 , the electric charge eliminating member  72  may be provided in a cylindrical shape. Both sides  72   a  and  72   b  of the electric charge eliminating member  72  may be connected to the ground source  75  and the power source  77 . An outer circumference  72   c  of the electric charge eliminating member  72  may contact the printing medium. 
     In another exemplary embodiment, referring to  FIG. 6 , the electric charge eliminating member  73  may include a plate-shaped body  73   a  and pointed protrusions  73   b . The protrusions  73   b  may contact the printing medium. Accordingly, the electric charge elimination efficiency of the electric charge eliminating member  73  may be further enhanced. 
       FIG. 7  is a schematic diagram illustrating a toner neutralization module according to an exemplary embodiment. The toner neutralization module  70 B may be arranged on the travel path P of the printing medium between the developing module  30  and the fixing module  50 . The toner neutralization module  70 B may include an ion spraying member  74 . The ion spraying member  74  may spray onto the printing medium M ions having opposite polarity to the electrified charges on the toner image. For example, if electrons are electrified on the toner image, positive ions may be sprayed onto the printing medium M. 
     In at least one exemplary embodiment, the toner image may be electrically neutralized by the ion spraying member  74  before being fixed. As explained above, if the toner image is neutralized, the amount of the activated SVOC  204  is reduced, and the amount of the FP and UFP  210  (charged and uncharged) is also reduced. 
     The electromagnetic filter module  80 A will be explained below. 
       FIG. 8  is a cross-sectional view of an electromagnetic filter module  80 A. In at least one exemplary embodiment, the electromagnetic filter module  80 A may be installed proximate to a paper ejection outlet  12   a .  FIG. 9A  is a perspective view of the electromagnetic filter module  80 A of  FIG. 8  according to an exemplary embodiment, and  FIG. 9B  is a perspective view of an electromagnetic filter module  82  as an alternative to the electromagnetic filter module  80 A of  FIG. 9A , according to an exemplary embodiment. 
     Referring to  FIGS. 8 and 9A , the electromagnetic filter module  80 A may be installed on the upper casing  12  of the image forming apparatus  1 , and arranged adjacent to the paper ejection outlet  12   a . The electromagnetic filter module  80 A may include a magnetic field forming member  81 . The magnetic field forming member  81  may be a rectangular plate of permanent magnet. It can be appreciated, however, that the magnetic field forming member  81  may be formed of various different shapes. Alternatively, the magnetic field forming member may include an electrically conductive winding and a current source to drive current through the winding. Accordingly, an electric field may be induced to attract magnetic material, as discussed in greater detail below. 
     If the FP and UFP produced in the image forming apparatus  1  include magnetic materials such as Fe, for example, the magnetic materials are attracted by the magnetic field formed by the magnetic field forming member  81  and are adhered to a lower surface  81   a  of the magnetic field forming member  81 . Therefore, the amount of FP and UFP discharged from the paper ejection outlet  12   a  may be reduced. 
     The magnetic field forming member  81  is not limited to take a rectangular plate form, and may be realized as other forms. In one exemplary embodiment, referring to  FIG. 9B , a cylindrical-shaped magnetic field forming member  82  may be provided and, in this case, the FP and UFP are adhered to an outer circumference  82   a  of the magnetic field forming member  82 . 
       FIG. 10  is a schematic perspective view of the electromagnetic filter module according to a second exemplary embodiment, and  FIG. 11  is a schematic perspective view of the electromagnetic filter module according to a third exemplary embodiment. 
     Referring to  FIG. 10 , the electromagnetic filter module  80 B as an alternative to the electromagnetic filter module  80 A may include an electromagnet which includes a core member  83  and coils  83   b . The coils  83   b  are wound around the rod-shaped core member  83  and the current of a power source  85  flows on the coils  83   b  so that the magnetic field is produced around the core member  83 . The reference numeral  86  refers to resistance of the wire forming the coils. 
     Since the magnetic field is formed around the core member  83  of the electromagnetic filter module  80 B, the FP and UFP are adhered to the outer circumference  83   a  of the core member  83 , and as a result, the amount of the discharged FP and UFP is reduced. Intermittently resetting the voltage  85  applied to the coils  83   b  allows the release of the FP and UFP from the core member  83 , i.e., cleans the core member  83  to maintain effectiveness. 
     Referring to  FIG. 11 , the electromagnetic filter module  80 C according to a third exemplary embodiment may include an electromagnetic field forming member  84  and a power source  87 . The electromagnetic field forming member  84  may be conductive material such as Cu, and may have a rod-like shape, but is not limited thereto. Both sides  84   a  and  84   b  of the electromagnetic field forming member  84  may be connected to the power source  87  so that the electrical current flows to the electromagnetic field forming member  84 . The reference numeral  88  is resistance of the wire forming the coils. 
     When the electric current flows through the electromagnetic field forming member  84 , the electromagnetic field forming member  84  forms the electromagnetic field. Referring to  FIG. 11 , the electrified FP and UFP are adhered to the surface  84   c  of the electromagnetic field forming member  84  by the electromagnetic field. Thus, an amount of the FP and UFP discharged from the image forming apparatus  1  may be reduced. 
     Referring to  FIG. 11 , the electromagnetic field forming member  84  may be separately provided from the electric wire. However, in another exemplary embodiment, the electric wire itself may be implemented as the electromagnetic field forming member  84 . 
       FIG. 12  is a schematic cross-sectional view of the electromagnetic filter module  80 A installed near an air ventilation outlet according to an exemplary embodiment. 
     Referring to  FIG. 12 , the electromagnetic filter module  80 A (see  FIG. 9A ) may be installed adjacent to the air ventilation outlet/vent  11  a formed in the side casing/wall  11 . The electromagnetic filter module  80 A may be provided on an installation member/ledge  13  extended from the side casing/wall  11 . 
     While the air in the image forming apparatus  1  is guided to the air ventilation outlet  11   a  along the air passage (AF), the FP and UFP included in the air are adhered to the electromagnetic filter module  80 A. Thus, the amount of the FP and UFP discharged from the image forming apparatus  1  may be reduced. 
     As illustrated in  FIG. 13 , in an exemplary embodiment, an image forming apparatus  1300  has at least a developing module  1314  and a fixing module  1312  that perform an electrophotographic printing method, the image forming apparatus  1300  including a printing system  1302  and an harmful material reducing module  1304 . The printing system  1302  is in electrical communication with a power source  1306  and includes at least a developing module  1314  that develops a toner image on a printing medium that travels on a travel path  1316  to a fixing module  1312  that fixes the toner image onto the printing medium. Further, the harmful material reducing module  1304  includes at least one of an electric charge eliminating member  1310 , in electrical communication with the power source  1306  and arranged on the travel path  1316  of the printing medium between the developing module  1314  and the fixing module  1312 , to neutralize electrified charges of a toner image on the printing medium and an electromagnetic filter module  1308 , in electrical communication with the power source  1306  and arranged proximate to a printing medium ejection outlet  1318 , to attract charged fine particles and ultrafine particles, minimizing output of the fine particles and ultrafine particles. 
     The electric charge eliminating member  1310  may be one of an electrically conductive material that includes one of a rectangular plate form, a cylindrical shape, and a plate-shaped body with pointed protrusions, and/or may be an ion-spraying member. 
     The electromagnetic filter module  1308  may include one of a rectangular plate of a permanent magnet, a cylindrical-shaped magnetic field forming member, an electromagnet that includes a core member and coils, and an electromagnetic field forming member in electrical communication with the power source. 
     In an exemplary embodiment, as illustrated in  FIG. 13 , an image forming apparatus  1300  performs an electrophotographic printing method and minimizes output of charged fine particles and ultrafine particles. The image forming apparatus  1300  includes a printing system  1302  which is in electrical communication with a power source  1306  and an harmful material reducing module  1304 . The harmful material reducing module  1304  includes at least one of an electric charge eliminating member  1310  and an electromagnetic filter module  1308 . The electric charge eliminating member  1310  is in electrical communication with the power source  1306  and is arranged on a travel path  1316  of a printing medium in the printing system  1302  to neutralize electrified charges of a toner image on the printing medium. In addition, the electromagnetic filter module  1308  is in electrical communication with the power source  1306  and is arranged proximate to a printing medium ejection outlet  1318  to attract charged fine particles and ultrafine particles, minimizing output of the fine particles and ultrafine particles. 
     The printing system  1302  may include at least a developing module  1314  that develops the toner image on the printing medium that travels on the travel path  1316  and a fixing module  1312  that fixes the toner image onto the printing medium. 
     As illustrated in  FIG. 12 , in an exemplary embodiment, an image forming apparatus includes a filter unit  1200  formed with a wall  11  of the image forming apparatus to filter undesired particles traveling along an outlet path. The filter unit  1200  may include at least one air ventilation outlet/vent  11   a  formed in the wall  11  and aligned with the outlet path to receive the undesirable particles therethrough and an electromagnetic filter module  80 A disposed adjacent the at least one vent  11   a  to generate a magnetic field that attracts the undesirable particles traveling toward the vent  11 A to the electromagnetic filter module  80 A. 
     The electromagnetic filter module  80 A may include a surface facing the outlet path such that the undesirable particles adhere to the surface due to an electromagnetic attractive force of the electromagnetic filter module  80 A. Further, a ledge  13  may extend parallel with the outlet path and may have a surface facing the outlet path. The electromagnetic filter module  80 A may be coupled to the ledge  13  and may face the outlet path. 
     In addition, the at least one vent may include a plurality of vents, each vent aligned with a respective outlet path to receive undesired particles passing therethrough. 
     The electromagnetic filter module s  80 A,  80 B, and  80 C explained above may include any one of the magnetic field forming member  81 ,  82  and the electromagnetic field forming member  84 . In another exemplary embodiment, to enhance the FP and UFP filtering efficiency, the electromagnetic filter module  80 A,  80 B,  80 C may include both the magnetic field forming member  81 ,  82  and electromagnetic field forming member  84 . For example, the electromagnetic filter module  80 A,  80 B,  80 C may include the magnetic field forming member  81  of  FIG. 9A  and the electromagnetic field forming member  84  of  FIG. 11 . 
     Meanwhile, although the image forming apparatus  1  explained above may include both the toner neutralization,  70 A and/or  70 B and the electromagnetic filter module  80 A,  80 B, and/or  80 C, the image forming apparatus may also include merely one of the toner neutralization module  70 A or  70 B and the electromagnetic filter module,  80 A,  80 B, or  80 C. 
     According to the exemplary embodiments explained above, since the toner image is electrically neutralized by the toner neutralization module  70 A and/or  70 B, and the electromagnetic filter module  80 A,  80 B, and/or  80 C secondly filters the FP and UFP electromagnetically, the image forming apparatus  1  may significantly reduce the discharged amount of the FP and UFP. 
     Further, according to the exemplary embodiments, since the toner neutralization module s  70 A and  70 B and the electromagnetic filter modules s  80 A,  80 B, and  80 C are applicable to the conventional toners, it is not required to develop the toner fixable at low-temperature and re-set the control conditions of the image forming apparatus. As a result, the amount of discharged FP and UFP may be reduced at low cost. 
     Although a few exemplary embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these exemplary embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the appended claims and their equivalents.