Image forming device

Abstract

The present invention provides an image forming device. The image forming device comprises: an image holding unit that holds an image formed by a developer, the image being an image intended for transfer to a medium and an image not intended for transfer to a medium; a transfer unit that transfers the image intended for transfer to the medium to the medium; and a forming unit that, upon receiving a print instruction to form the image intended for transfer to the medium on the image holding unit, forms the image not intended for transfer to the medium at a position on the image holding unit where the image intended for transfer to the medium is to be formed.

Description

Technical Field

[0001] The present disclosure relates to an image forming apparatus. Background Art

[0002] In image forming apparatuses such as copiers, printers, and FAXes, the following three patent documents are known as technologies for forming images that are not intended to be transferred to a medium.

[0003] Japanese Patent No. 6340927 describes a technique for forcibly consuming toner that has deteriorated due to agitation without being consumed within a developing device. This technique forms a band-like toner image in the non-image area between toner images. In this technique, when the recording medium width is smaller than the maximum width, the image density of the band-like toner image is increased or the image length is lengthened, thereby consuming a large amount of deteriorated toner.

[0004] Japanese Patent Application Laid-Open No. 2006-251138 describes a technique for forming a toner band outside an image forming area. If the printed image is darker, the toner band is made lighter; if the printed image is lighter, the toner band is made darker, so as to maintain a constant toner supply amount to the cleaning device.

[0005] Japanese Patent Application Laid-Open No. 2006-221106 describes a technique in which, in a monochrome image forming mode, a toner band is formed on a photosensitive drum not performing image formation to maintain lubricity of a cleaning blade, and the toner amount of the toner band on the most upstream photosensitive drum is maximized. Summary of the Invention

[0006] The technical problem of the present disclosure is to suppress the occurrence of transfer failure to a medium, compared with a case where an image not intended for transfer to a medium is formed before forming an image intended for transfer to a medium.

[0007] According to a first aspect of the present disclosure, an image forming device is provided, comprising: an image holding unit that holds an image formed by a developer, the image being an image intended for transfer to a medium and an image not intended for transfer to a medium; a transfer unit that transfers the image intended for transfer to the medium to the medium; and a forming unit that, upon receiving a print instruction to form the image intended for transfer to the medium on the image holding unit, forms the image not intended for transfer to the medium at a position on the image holding unit where the image intended for transfer to the medium is formed.

[0008] According to the second aspect of the present disclosure, the image not intended to be transferred to the medium is a halftone image.

[0009] According to the third embodiment of the present disclosure, the forming unit has: a first forming mode for a first medium; and a second forming mode for a second medium having a transfer sensitivity lower than that of the first medium. In the case of the first forming mode, before an image for transfer to the medium is formed on the image holding unit, an image not for transfer to the medium is formed at a position on the image holding unit where the image for transfer to the medium is formed.

[0010] According to a fourth aspect of the present disclosure, the first medium includes embossed paper or Japanese paper.

[0011] According to a fifth aspect of the present disclosure, the second medium includes thin paper, plain paper, thick paper, or coated paper.

[0012] According to the sixth aspect of the present disclosure, the image forming apparatus includes an input unit to which a user can input an instruction for executing an operation of forming an image not intended for transfer to the medium on the image holding unit.

[0013] According to the seventh aspect of the present disclosure, the forming unit forms an image that is not intended to be transferred to the medium while the image holding unit rotates a plurality of times.

[0014] According to the eighth aspect of the present disclosure, the image not intended to be transferred to the medium has a predetermined length along the rotation direction of the image holding unit.

[0015] According to the 9th scheme of the present disclosure, the forming unit forms images that are not intended to be transferred to the medium with gaps between the images that are not intended to be transferred to the medium, and in the next and subsequent rotations of the image holding unit, images that are not intended to be transferred to the medium are formed in an area overlapping with the gaps.

[0016] According to the tenth aspect of the present disclosure, an image not intended to be transferred to the medium is formed in the region overlapping with all the gaps.

[0017] According to the eleventh aspect of the present disclosure, the forming unit forms an image not intended for transfer to the medium, corresponding to a portion of the image intended for transfer to the medium.

[0018] According to the twelfth aspect of the present disclosure, the forming unit forms an image not intended for transfer to the medium that corresponds to the entire image intended for transfer to the medium.

[0019] According to the thirteenth aspect of the present disclosure, an image not intended to be transferred to the medium is also formed at a position different from the image intended to be transferred to the medium.

[0020] According to the fourteenth aspect of the present disclosure, the forming unit forms the image not intended for transfer to the medium covering the entire region where the image intended for transfer to the medium can be formed.

[0021] According to the 15th embodiment of the present disclosure, there is provided an image forming device comprising: an image holding unit which holds an image formed by a developer, the image being an image intended to be transferred to a medium and an image not intended to be transferred to a medium; a transfer unit which transfers the image intended to be transferred to the medium to the medium; and a forming unit which forms an image not intended to be transferred to the medium and holds it on the surface of the image holding unit when a predetermined condition for supplying the developer to the surface of the image holding unit is satisfied.

[0022] According to the sixteenth aspect of the present disclosure, the forming unit forms an image that is not intended to be transferred to the medium while the image holding unit rotates a plurality of times.

[0023] According to the seventeenth aspect of the present disclosure, the image not intended to be transferred to the medium has a predetermined length along the rotation direction of the image holding unit.

[0024] According to the 18th embodiment of the present disclosure, the forming unit forms images that are not intended to be transferred to the medium with gaps between the images that are not intended to be transferred to the medium, and in the next and subsequent rotations of the image holding unit, images that are not intended to be transferred to the medium are formed in an area overlapping with the gaps.

[0025] (Effect)

[0026] According to the first or fifteenth aspect, compared with a case where an image not intended for transfer to a medium is formed before forming an image intended for transfer to a medium, occurrence of transfer failure to a medium can be suppressed.

[0027] According to the second aspect, a halftone image can be used as an image not intended to be transferred to a medium.

[0028] According to the third aspect, compared with the case where an image not intended to be transferred to a medium is formed in the second mode, the consumption of developer can be suppressed.

[0029] According to the fourth aspect, embossed paper or Japanese paper can be used as the first medium.

[0030] According to the fifth aspect, thin paper, plain paper, thick paper, or coated paper can be used as the second medium.

[0031] According to the sixth aspect, an image not intended for transfer to a medium can be formed at an arbitrary timing by inputting to the input unit.

[0032] According to the seventh or sixteenth aspect, transfer failure can be stably suppressed compared to a case where an image not intended to be transferred to a medium is formed only during one rotation of the image holding unit.

[0033] According to the eighth or seventeenth aspect, the developer can be stably supplied to the region corresponding to the length in the rotation direction.

[0034] According to the ninth or eighteenth aspect, compared with a case where an image not intended to be transferred to a medium is formed without forming a gap, transfer failure can be suppressed over the entire area of ​​the image holding unit.

[0035] According to the tenth aspect, an image not intended to be transferred to the medium can be formed in the region overlapping with all the gaps.

[0036] According to the eleventh aspect, wasteful consumption of developer can be suppressed compared to a case where an image not intended for transfer to a medium is formed even in a portion where no image not intended for transfer to a medium is required.

[0037] According to the twelfth aspect, wasteful consumption of developer can be suppressed compared to a case where an image not intended to be transferred to a medium is formed in correspondence with an image intended to be transferred to a medium.

[0038] According to the thirteenth aspect, transfer failure can be suppressed compared to a case where an image not intended for transfer to a medium is not formed at a position where the image not intended for transfer to a medium should be formed.

[0039] According to the fourteenth aspect, transfer failure can be stably suppressed compared to a case where an image not intended for transfer to a medium is formed covering the entire area of ​​the image intended for transfer to a medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is an overall explanatory diagram of the image forming apparatus of Example 1.

[0041] Figure 2 This is an enlarged explanatory diagram of the visible image forming apparatus of Example 1.

[0042] Figure 3 This is a diagram showing, in block form, the functions of the control section of the image forming apparatus according to the first embodiment.

[0043] Figure 4 FIG. 1 is an explanatory diagram of an example of a toner supply image of Example 1. Figure 4(A) is an explanatory diagram of an image forming area and a non-forming area. Figure 4 (B) is an explanatory diagram of a toner supply image for the odd-numbered turns of the intermediate transfer belt. Figure 4 (C) is an explanatory diagram of a toner supply image for an even-numbered turn of the intermediate transfer belt.

[0044] Figure 5 This is an explanatory diagram of a flowchart of a toner supply image forming process according to the first embodiment.

[0045] Figure 6 This is a diagram illustrating the voltage acting in the transfer area. Figure 6 (A) is an explanatory diagram of an example of low-sensitivity paper. Figure 6 (B) is an explanatory diagram of an example of embossed paper. Figure 6 (C) is an explanatory diagram of an example of Japanese paper.

[0046] Figure 7 This is a graph showing experimental results of the adhesion of the developer to the intermediate transfer belt, with the vertical axis representing the adhesion.

[0047] Figure 8 This is an explanatory diagram of the relationship between an example of an image intended to be transferred to a medium and a toner supplied image.

[0048] Figure 9 is an explanatory diagram of an example of a change in a toner supply image. Figure 9 (A) is an explanatory diagram of a state in which a toner supply image corresponds to the entire image to be transferred. Figure 9 (B) is an explanatory diagram of a case where a toner supply image is formed at a position different from the image to be transferred. Figure 9 (C) is an explanatory diagram of a case where a toner supply image corresponds to a portion of an image to be transferred. DETAILED DESCRIPTION

[0049] Next, specific examples (hereinafter referred to as examples) of the embodiments of the present disclosure will be described with reference to the drawings. However, the present disclosure is not limited to the following examples.

[0050] In addition, to facilitate understanding of the subsequent description, in the accompanying drawings, the front-to-back direction is the X-axis direction, the left-to-right direction is the Y-axis direction, the up-down direction is the Z-axis direction, and the directions indicated by the arrows X, -X, Y, -Y, Z, -Z or the sides indicated by these are respectively the front, rear, right, left, top, bottom or the front side, rear side, right side, left side, top side, and bottom side.

[0051] In the drawings, an arrow with “·” in “○” indicates an arrow pointing from the back side to the front side of the paper, and an arrow with “×” in “○” indicates an arrow pointing from the front side to the back side of the paper.

[0052] In the following description using the drawings, illustration of components other than those necessary for the description is appropriately omitted for ease of understanding.

[0053] [Example 1]

[0054] Figure 1 This is an overall explanatory diagram of the image forming apparatus of Example 1.

[0055] Figure 2 This is an enlarged explanatory diagram of the visible image forming apparatus of Example 1.

[0056] exist Figure 1 In the figure, a copy machine U as an example of an image forming device includes: a user interface UI as an example of an operating unit; a scanning unit U1 as an example of an image reading device; a paper feeding unit U2 as an example of a medium supply device; an imaging unit U3 as an example of an image recording device; and a medium processing device U4.

[0057] (Description of the user interface UI)

[0058] The user interface UI includes input buttons UIa used to start copying or set the number of copy pages, etc. The user interface UI also includes a display unit UIb that displays the contents inputted via the input buttons UIa or the status of the copy machine U.

[0059] (Description of Paper Feed Unit U2)

[0060] exist Figure 1 The paper feed unit U2 includes a plurality of paper feed trays TR1, TR2, TR3, and TR4, which serve as examples of media storage containers. Furthermore, the paper feed unit U2 includes a media supply path SH1, which removes recording paper S, which serves as an example of image recording media, from the paper feed trays TR1 to TR4 and transports it to the image forming unit U3.

[0061] (Description of Imaging Unit U3 and Medium Processing Device U4)

[0062] exist Figure 1 In the image forming unit U3 , the image recording unit U3 includes an image recording unit U3 a that records an image on the recording paper S conveyed from the paper feeding unit U2 based on the document image read by the scanner unit U1 .

[0063] exist Figure 1 、 Figure 2In the image forming unit U3, the latent image forming device drive circuit D outputs drive signals corresponding to the image information input from the scanner unit U1 to the latent image forming devices ROSy, ROSm, ROSc, and ROSk of each color Y through K at predetermined timings. Photosensitive drums Py, Pm, Pc, and Pk, serving as an example of image holders, are arranged below each of the latent image forming devices ROSy through ROSk.

[0064] The surfaces of the rotating photosensitive drums Py, Pm, Pc, and Pk are uniformly charged by charging rollers CRy, CRm, CRc, and CRk, respectively, as examples of chargers. Electrostatic latent images are formed on the charged surfaces of the photosensitive drums Py to Pk by laser beams Ly, Lm, Lc, and Lk, as examples of latent image writing light, output by latent image forming devices ROSy, ROSm, ROSc, and ROSk. The electrostatic latent images on the surfaces of the photosensitive drums Py, Pm, Pc, and Pk are developed into toner images, as examples of visible images, of yellow (Y), magenta (M), cyan (C), and black (K), by developing devices Gy, Gm, Gc, and Gk.

[0065] The developer consumed by development in the developing devices Gy to Gk is supplied from toner cartridges Ky, Km, Kc, and Kk, which are examples of developer storage containers. The toner cartridges Ky, Km, Kc, and Kk are detachably mounted on the developer supply device U3b.

[0066] The toner images on the surfaces of the photosensitive drums Py, Pm, Pc, and Pk are sequentially transferred, overlapping each other, onto an intermediate transfer belt B, an example of an intermediate transfer member, in the order of primary transfer areas Q3y, Q3m, Q3c, and Q3k by primary transfer rollers T1y, T1m, T1c, and T1k, an example of a primary transfer device. This forms a color toner image, an example of a multi-color visible image, on the intermediate transfer belt B. The color toner image formed on the intermediate transfer belt B is conveyed to a secondary transfer area Q4.

[0067] In the case of only K-color image information, only the K-color photosensitive drum Pk and the developing device Gk are used to form only a K-color toner image.

[0068] After the primary transfer, residual developer, paper dust, and other residues adhering to the surfaces of the photosensitive drums Py, Pm, Pc, and Pk are removed by drum cleaners CLy, CLm, CLc, and CLk, which are examples of cleaners for image holders.

[0069] In Example 1, the photosensitive drum Pk, charging roller CRk, and drum cleaner CLk are integrated into a K-color photosensitive unit UK, serving as an example of an image carrier unit. Similarly, for the other colors Y, M, and C, the photosensitive drums Py, Pm, and Pc, charging rollers Cry, CRm, and CRc, and drum cleaners CLy, CLm, and CLc form photosensitive units UY, UM, and UC, respectively.

[0070] Furthermore, the K-color photoreceptor unit UK and the developing device Gk having a developing roller R0k as an example of a developer holding member constitute a K-color visible image forming device UK+Gk. Similarly, the Y-color, M-color, and C-color photoreceptor units UY, UM, and UC and the developing devices Gy, Gm, and Gc having developing rollers R0y, R0m, and R0c respectively constitute the Y-color, M-color, and C-color visible image forming devices UY+Gy, UM+Gm, and UC+Gc.

[0071] A belt module BM, an example of an intermediate transfer device, is located below the photosensitive drums Py-Pk. The belt module BM includes an intermediate transfer belt B, an example of an image retention unit; a drive roller Rd, an example of a driving member for the intermediate transfer element; a tension roller Rt, an example of a tension-applying member; a stepping roller Rw, an example of a meandering prevention member; multiple idler rollers Rf, an example of a driven member; a backup roller T2a, an example of a counter member; and the primary transfer rollers T1y, T1m, T1c, and T1k. The intermediate transfer belt B is supported for rotation in the direction of arrow Ya.

[0072] A secondary transfer unit Ut is disposed below the support roller T2a. The secondary transfer unit Ut includes a secondary transfer roller T2b, an example of a secondary transfer unit. The area where the secondary transfer roller T2b contacts the intermediate transfer belt B forms a secondary transfer area Q4. Furthermore, the support roller T2a, an example of an opposing member, faces the secondary transfer roller T2b across the intermediate transfer belt B. A contact roller T2c, an example of a power supply member, contacts the support roller T2a. A secondary transfer voltage having the same polarity as the toner charge polarity is applied to the contact roller T2c.

[0073] The backup roller T2 a , the secondary transfer roller T2 b , and the contact roller T2 c constitute a secondary transfer device T2 as an example of a transfer unit.

[0074] A medium transport path SH2 is located below the belt module BM. Recording paper S, supplied from the medium supply path SH1 of the paper feed unit U2, is conveyed by transport rollers Ra, an example of a medium transport member, to registration rollers Rr, an example of a member that adjusts the transport timing. Registration rollers Rr convey the recording paper S downstream in sync with the time at which the toner image formed on the intermediate transfer belt B is conveyed to the secondary transfer area Q4. The recording paper S fed by registration rollers Rr is guided by a paper guide SGr on the side where registration rollers Rr are located and by a pre-transfer paper guide SG1, and is then conveyed to the secondary transfer area Q4.

[0075] When the toner image on the intermediate transfer belt B passes through the secondary transfer area Q4, it is transferred by the secondary transfer device T2 onto the recording paper S. In the case of a color toner image, the primary transferred toner image superimposed on the surface of the intermediate transfer belt B is transferred to the recording paper S at once.

[0076] The primary transfer rollers T1y to T1k, the secondary transfer device T2, and the intermediate transfer belt B constitute the transfer device T1y to T1k+T2+B of the first embodiment.

[0077] After the secondary transfer, the intermediate transfer belt B is cleaned by a belt cleaner CLB, an example of an intermediate transfer body cleaner, located downstream of the secondary transfer area Q4. The belt cleaner CLB, an example of a removal member, removes residual materials such as developer and paper dust that remain untransferred in the secondary transfer area Q4 from the intermediate transfer belt B.

[0078] The recording paper S with the toner image transferred thereto is guided by the paper guide SG2 after the transfer and conveyed to the medium conveying belt BH as an example of a conveying member.

[0079] The fixing device F includes a heating roller Fh, an example of a heating member, and a pressure roller Fp, an example of a pressure member. The recording paper S is conveyed to a fixing area Q5, where the heating roller Fh and the pressure roller Fp come into contact. The toner image on the recording paper S is heated and pressurized by the fixing device F as it passes through the fixing area Q5, thereby being fixed.

[0080] The visible image forming devices UY+Gy to UK+Gk, the transfer devices T1y to T1k+T2+B, and the fixing device F constitute an image recording section U3a as an example of an image forming unit in the first embodiment.

[0081] A switching gate GT1, an example of a switching member, is provided downstream of the fixing device F. The switching gate GT1 selectively switches between the discharge path SH3 and the reversing path SH4, allowing the recording paper S that has passed through the fixing area Q5 to be conveyed to either the discharge path SH3 or the reversing path SH4, which extend toward the media processing device U4. The recording paper S conveyed to the discharge path SH3 is conveyed to the paper conveying path SH5 of the media processing device U4. A curl correction member U4a, an example of a warp correction member, is provided in the paper conveying path SH5. The curl correction member U4a corrects the warping, so-called curl, of the conveyed recording paper S. The recording paper S with corrected curl is discharged by the discharge roller Rh, an example of a medium discharge member, with the image-fixed surface of the paper facing upward, to the discharge tray TH1, an example of a medium discharge unit.

[0082] The recording paper S conveyed to the reversing path SH4 of the image forming unit U3 through the switching gate GT1 passes through the second gate GT2 as an example of a switching member and is conveyed to the reversing path SH4 of the image forming unit U3 .

[0083] At this time, when the recording paper S is discharged with the image-fixed surface facing downward, the recording paper S's conveying direction is reversed after its trailing end passes through the second gate GT2. In Example 1, the second gate GT2 is constructed of a film-like elastic member. Therefore, the second gate GT2 temporarily allows the recording paper S conveyed to the reversing path SH4 to pass directly. Once the recording paper S has passed through, and is reversed, or so-called switched back, it is guided to the conveying paths SH3 and SH5. The switched-back recording paper S then passes through the curl correction unit U4a and is discharged onto the discharge tray TH1 with the image-fixed surface facing downward.

[0084] The reversing path SH4 of the image forming unit U3 is connected to a circulation path SH6 , and a third gate GT3 as an example of a switching member is disposed at the connection portion. The downstream end of the reversing path SH4 is connected to a reversing path SH7 of the media processing device U4 .

[0085] The recording paper S conveyed to the reversing path SH4 through the switching gate GT1 is conveyed to the reversing path SH7 of the media processing device U4 through the third gate GT3. Similar to the second gate GT2, the third gate GT3 of Example 1 is constructed from a film-like elastic member. Therefore, the third gate GT3 temporarily allows the recording paper S conveyed through the reversing path SH4 to pass through. Once the recording paper S has passed through, it is redirected to the circulation path SH6.

[0086] The recording paper S conveyed to the circulation path SH6 is transported again to the secondary transfer area Q4 through the medium conveyance path SH2 , and printing is performed on the side of the recording paper S opposite to the image-fixed side.

[0087] The elements denoted by the reference numerals SH1 to SH7 constitute a paper conveyance path SH, and the elements denoted by the reference numerals SH, Ra, Rr, Rh, SGr, SG1, SG2, BH, and GT1 to GT3 constitute a paper conveyance device SU of the first embodiment.

[0088] (Description of the Control Unit of Example 1)

[0089] Figure 3 This is a diagram showing, in block form, the functions of the control section of the image forming apparatus according to the first embodiment.

[0090] exist Figure 3 In the embodiment, the control unit (controller) C, which is an example of a control unit of the copier U, has an input / output interface I / O for inputting and outputting signals to and from the outside. In addition, the control unit C has a ROM: Read Only Memory that stores programs and information for performing necessary processing. In addition, the control unit C has a RAM: Random Access Memory that temporarily stores necessary data. In addition, the control unit C has a CPU: Central Processing Unit that performs processing corresponding to the programs stored in the ROM, etc. Therefore, the control unit C of Example 1 is composed of a small information processing device, a so-called microcomputer. As a result, the control unit C can realize various functions by executing the programs stored in the ROM, etc.

[0091] (Signal output element connected to control unit C)

[0092] The control unit C receives an output signal from a signal output element such as a user interface UI.

[0093] The user interface UI includes, as an example of input means, input buttons UIa for inputting a copy start key, numeric keys, arrow keys, etc., a display unit UIb, and a recovery mode start button UIc for enabling input to start the recovery mode.

[0094] The recovery mode start button UIc allows the user to input an instruction to execute a recovery mode in which a toner supply image is formed on the intermediate transfer belt B as an example of an image holding unit, which is not intended to be transferred to the recording paper S.

[0095] The various input buttons UIa and the recovery mode start button UIc are not limited to being hardware buttons, but may be buttons displayed as images on an input-enabled display unit UIb such as a touch panel.

[0096] (Controlled element connected to control unit C)

[0097] The control unit C is connected to the driving circuit D1 of the main driving source, the power supply circuit E, and other control elements (not shown). The control unit C outputs control signals to the circuits D1 and E, and the like.

[0098] D1: driving circuit of the main driving source

[0099] The driving circuit D1 of the main driving source rotationally drives the photosensitive drums Py to Pk, the intermediate transfer belt B, and the like via a main motor M1 as an example of the main driving source.

[0100] E: Power circuit

[0101] The power supply circuit E includes a power supply circuit Ea for development, a power supply circuit Eb for charging, a power supply circuit Ec for transfer, a power supply circuit Ed for fixing, and the like.

[0102] Ea: Power supply circuit for development

[0103] The power supply circuit Ea for development applies a development voltage to the developing rollers of the developing devices Gy to Gk.

[0104] Eb: Power supply circuit for live use

[0105] The charging power supply circuit Eb applies a charging voltage for charging the surfaces of the photosensitive drums Py to Pk to the charging rollers CRy to CRk, respectively.

[0106] Ec: Power supply circuit for transfer

[0107] The power supply circuit Ec for transfer applies a transfer voltage to the primary transfer rollers T1y to T1k or the backup roller T2a.

[0108] Ed: Power supply circuit for fixing

[0109] The fixing power supply circuit Ed supplies power to the heater of the heating roller Fh of the fixing device F.

[0110] (Function of Control Unit C)

[0111] The control unit C has a function of executing processing according to the input signal from the signal output element and outputting a control signal to each of the control elements.

[0112] C1: Control unit for image formation

[0113] The image formation control unit C1 controls the driving of components of the scanner unit U1 or the image forming unit U3 and the timing of applying voltages based on image information input to the user interface UI or from an external personal computer, thereby executing a task as an image forming operation.

[0114] C2: Control unit of the drive source

[0115] The driving source control unit C2 controls the driving of the main motor M1 via the main driving source driving circuit D1 , and controls the driving of the photosensitive drums Py to Pk and the like.

[0116] C3: Control unit of the power circuit

[0117] The power circuit control unit C3 controls the power circuits Ea to Ed, and controls the voltage applied to each component or the power supplied to each component.

[0118] C4: Storage unit of media type

[0119] The media type storage unit C4 stores the type of recording paper S, an example of the media being used. The media type storage unit C4 of Example 1 stores the type of recording paper S stored in each of the paper feed trays TR1 to TR4 of the paper feed unit U2 for each of the paper feed trays TR1 to TR4. Furthermore, in Example 1, the type of recording paper S stored in each of the paper feed trays TR1 to TR4 is stored and registered via input from the user interface UI. The type of recording paper S can be set by selecting from among "thin paper," "plain paper," "thick paper," "embossed paper," "Japanese paper," and "coated paper." For example, the type of recording paper S can also be set by directly inputting the "paper weight per square meter."

[0120] C5: Medium type identification unit

[0121] The media type determination unit C5 determines the type of recording paper S used for printing. The media type determination unit C5 of Example 1 determines the type of recording paper S based on information about the types of recording paper S in the paper feed trays TR1 to TR4 stored in the media type storage unit C4 and the paper feed trays TR1 to TR4 used for printing. Furthermore, the media type determination unit C5 of Example 1 determines whether the recording paper S is embossed paper or Japanese paper, an example of media with high transfer sensitivity, or thin paper, plain paper, thick paper, or coated paper, an example of media with low transfer sensitivity.

[0122] In addition, in the present specification and claims, "transfer sensitivity" refers to the degree to which the image is not easily transferred to the recording paper S, and the degree to which the image is easily transferred if the back side is turned over. The situation where poor transfer is likely to occur even when the environment such as temperature and humidity or the applied voltage changes, the conveying speed, etc. changes slightly is described as "high transfer sensitivity", and on the contrary, the situation where poor transfer is not likely to occur is described as "low transfer sensitivity". Therefore, thin paper or ordinary paper, thick paper, and coated paper with a smooth surface and roughly uniform density of fibers such as pulp have low transfer sensitivity. On the other hand, embossed paper with uneven surface or Japanese paper (low-density medium) with uneven density of pulp and a large number of voids inside have high transfer sensitivity. The reason is that Figure 6 The reason mentioned later is that in embossed paper or Japanese paper, when the transfer voltage is applied, if the resistance values ​​of the concave or gap part (the part without fibers) and the part with fibers are different or discharge occurs in the concave or gap, the transfer voltage will change and poor transfer will easily occur.

[0123] In the following description, embossed paper and Japanese paper may be referred to as “high-sensitivity paper” as an example of the first medium, and plain paper may be referred to as “low-sensitivity paper” as an example of the second medium.

[0124] Furthermore, while Example 1 illustrates the case where the media type is determined based on information stored in the media type storage unit C4, this is not limiting. For example, a configuration could also be employed in which a sensor, as an example of a detection component, is provided on the paper feed trays TR1-TR4 of the paper feed unit U2 or on the transport paths SH1 and SH2 from the paper feed trays TR1-TR4 to the registration rollers Rr. The sensor detects the type of media based on thickness, transmittance, reflectivity, polarization characteristics, surface roughness, or other factors. This allows the type of recording paper S used for printing to be detected and determined. For example, if the surface roughness of the recording paper S detected by the sensor is greater than a predetermined value (threshold), i.e., if the surface roughness is significantly uneven, the recording paper can be determined to be high-sensitivity paper. Furthermore, if the density (weight / (thickness x area)) of the recording paper S detected by the sensor is less than a predetermined value (threshold), i.e., if the recording paper S has a large internal void space, the recording paper can be determined to be high-sensitivity paper.

[0125] C6: Counting unit for printed pages

[0126] The print page count unit C6, which is an example of a unit for counting the number of transfers, counts the number of print pages, which is an example of the number of transfers. Specifically, the print page count unit C6 counts how many times a print image, which is an example of an image intended for transfer, has been transferred onto the recording paper S. Furthermore, in Example 1, when a toner supply image, which is an example of an image not intended for transfer, is formed (described later), the print page count is initialized, or so-called reset.

[0127] C7: Toner supply start determination unit

[0128] The toner supply start determination unit C7 determines whether it is time to form a toner supply image. The toner supply start determination unit C7 of Example 1 determines that it is time to form a toner supply image when predetermined conditions for supplying toner, an example of a developer, to the surface of the intermediate transfer belt B are met. For example, when using highly sensitive paper such as embossed paper, the toner supply start determination unit C7 determines that it is time to form a toner supply image before starting a job (a series of printing operations). Specifically, the copier U determines that it is time to form a toner supply image when it receives a print instruction to form a print image (an image intended for transfer) on the highly sensitive paper. Furthermore, the toner supply image is determined to be time to form when the number of pages counted by the print page count unit C6 since the last toner supply reaches a predetermined number as the job is executed. For example, the predetermined number of pages can be set to 10, but it can be arbitrarily changed based on design specifications, the sensitivity of the paper used, and other factors, such as page by page or every 100 pages. Furthermore, the toner supply start determination unit C7 of Example 1 also determines that the time has come to form a toner supply image when the recovery mode start button UIc is input. Therefore, in Example 1, three conditions are set as examples of conditions for supplying toner to the surface of the intermediate transfer belt B: before starting a job using high-sensitivity paper; when the number of printed pages in a job using high-sensitivity paper reaches a predetermined number; and when the recovery mode start button UIc is input.

[0129] Figure 4 FIG. 1 is an explanatory diagram of an example of a toner supply image of Example 1. Figure 4 (A) is an explanatory diagram of an image forming area and a non-forming area. Figure 4 (B) is an explanatory diagram of a toner supply image for the odd-numbered turns of the intermediate transfer belt. Figure 4 (C) is an explanatory diagram of a toner supply image for an even-numbered turn of the intermediate transfer belt.

[0130] C8: Forming unit for supplying an image (an example of a forming unit)

[0131] The supply image forming unit C8 forms a toner supply image 1, which is an example of an image not intended for transfer. When the toner supply start determining unit C7 determines that it is time to form the toner supply image 1, the supply image forming unit C8 forms the toner supply image 1 and transfers it to the intermediate transfer belt B. The belt cleaner CLB removes the toner supply image 1 without transferring it to the recording paper S.

[0132] exist Figure 4 In the embodiment 1, the intermediate transfer belt B is provided with an image area 2 as an example of an image forming area and an inter-image area 3 as an example of a non-forming area between the image areas 2. Figure 4 As shown in (B), the size of the toner supply image 1 is the same as the size of the image area 2. That is, the toner supply image 1 of Example 1 has the same length as the length L1 of the image area 2, which is an example of a predetermined length, along the rotation direction of the intermediate transfer belt B. Furthermore, the toner supply image 1 is formed at a distance equal to the length L2 of the inter-image area 3.

[0133] Furthermore, in the first embodiment, the toner supply image 1 is formed during the five rotations of the intermediate transfer belt B, for example. The number of rotations of the intermediate transfer belt B by which the toner supply image 1 is formed is not limited to five, and can be changed according to the design or specifications. Furthermore, in the first embodiment, as Figure 4 (B) Figure 4 As shown in (C), during the odd-numbered turns of the intermediate transfer belt B, a toner supply image 1 is formed at a position corresponding to image area 2. During the even-numbered turns, a toner supply image 1 is formed at a position corresponding to the gap between the toner supply images 1 during the odd-numbered turns, that is, at a position that overlaps (repeats) the inter-image area 3. While the configuration illustrated covers image area 2 during the odd-numbered turns and covers inter-image area 3 during the even-numbered turns, this is not limiting. For example, instead of two turns per group, three turns can be formed per group, with the second turn offset by a distance of (L1+L2) / 3 relative to the first turn, and the third turn offset by a distance of (L1+L2) / 3 relative to the second turn. Similarly, four turns per group, five turns per group, and so on are possible.

[0134] Furthermore, as an example, the toner supply image 1 of Example 1 uses an image with a total density of 200%, which is an image formed by overlapping intermediate tones of the colors Y, M, C, and K, each with a density of 50%. Furthermore, the density of the toner supply image 1 is not limited to the density shown in the example and can be set to any density. Furthermore, the colors of the toner used are not limited to four colors and can be set to three or fewer colors. Furthermore, the colors of the toner used can be set to a color that has degraded among the four colors, that is, a color for which the ratio of a predetermined low-density image to the accumulated number of printed pages is higher than a predetermined ratio. In this case, the toner supply image 1 can be formed using degraded toner, and the degraded toner can be forcibly consumed and replaced with new toner.

[0135] (Description of Flowchart of Example 1)

[0136] Next, the flow of control in the copy machine U according to the first embodiment will be described using a flowchart.

[0137] (Description of Flowchart of Toner Supply Image Formation Process)

[0138] Figure 5 This is an explanatory diagram of a flowchart of a toner supply image forming process according to the first embodiment.

[0139] Figure 5 The processing of each step ST of the flowchart is performed according to the program stored in the control unit C of the copy machine U. In addition, this processing is executed in parallel with other various processing of the copy machine U. Therefore, the processing of forming an image on each recording paper S with the start of the job is the same as the processing of the image forming process on each recording paper S. Figure 5 The flowcharts are executed in parallel.

[0140] Figure 5 The flowchart shown is started by turning on the power of the copy machine U.

[0141] exist Figure 5 In ST1, it is determined whether the operation has started. If yes (Y), the process proceeds to ST2, and if no (N), the process proceeds to ST11.

[0142] In ST2 , it is determined whether the recording paper S to be used is high-sensitivity paper. If not (N), the process proceeds to ST3 , and if yes (Y), the process proceeds to ST4 .

[0143] In ST3 , a low-sensitivity paper mode as an example of the second forming mode, that is, a normal image forming operation is executed, and the process returns to ST1 .

[0144] In ST4, the next processing (1) and (2) are executed, and the process proceeds to ST5.

[0145] (1) Temporarily stop the operation. That is, do not start the operation.

[0146] (2) Reset, i.e., initialize the cumulative number of printed pages.

[0147] In ST5, formation of the toner supply image 1 is started. Then, the process proceeds to ST6.

[0148] In ST6, it is determined whether a toner supply image 1 corresponding to a predetermined number of turns (5 turns in Example 1) has been formed. If yes (Y), the process proceeds to ST7, and if no (N), ST6 is repeated.

[0149] In ST7, the formation of the toner supply image 1 is completed. Then, the process proceeds to ST8.

[0150] In ST8, the next processing (1) and (2) are executed, and the process proceeds to ST9.

[0151] (1) Start or restart an operation.

[0152] (2) Start counting the cumulative number of printed pages.

[0153] In ST9, it is determined whether it is the time to form a toner supply image. If yes (Y), the process returns to ST4, and if no (N), the process proceeds to ST10.

[0154] In ST10, it is determined whether the job has been completed. If yes (Y), the process returns to ST1, and if no (N), the process returns to ST9.

[0155] In ST11, it is determined whether the recovery mode start button UIc has been input. If yes (Y), the process proceeds to ST12, and if no (N), the process returns to ST1.

[0156] In ST12, formation of the toner supply image 1 is started. Then, the process proceeds to ST13.

[0157] In ST13, it is determined whether a toner supply image 1 corresponding to a predetermined number of turns (5 turns in Example 1) has been formed. If yes (Y), the process proceeds to ST14, and if no (N), ST13 is repeated.

[0158] In ST14, the formation of the toner supply image 1 is completed. Then, the process returns to ST1.

[0159] (Effects of Example 1)

[0160] In the copier U of embodiment 1 having the above-described structure, when low-sensitivity paper is used, an image is formed in the low-sensitivity paper mode, and when high-sensitivity paper is used, an image is formed in the high-sensitivity paper mode including ST4 to ST10 as an example of the first forming mode.

[0161] Figure 6 This is a diagram illustrating the voltage acting in the transfer area. Figure 6 (A) is an explanatory diagram of an example of low-sensitivity paper. Figure 6 (B) is an explanatory diagram of an example of embossed paper. Figure 6 (C) is an explanatory diagram of an example of Japanese paper.

[0162] exist Figure 6 In the case of low-sensitivity paper (second medium) S1 such as plain paper, the surface is smooth and there are almost no voids inside. Therefore, the secondary transfer voltage V1 acts substantially uniformly in the secondary transfer area Q4.

[0163] On the other hand, Figure 6 As shown in (B), embossed paper S2, an example of highly sensitive paper (first medium), has uneven surfaces, with gaps 12 formed between the concave portions S2a and the intermediate transfer belt B. Consequently, the resistance in the thickness direction varies between the convex portions S2b (which lack gaps 12) and the concave portions S2a (which contain gaps 12). This makes discharge more likely to occur in gaps 12, and the applied secondary transfer voltage V1a may vary in the concave portions S2a. Consequently, transfer failures are more likely to occur in the concave portions S2a than with low-sensitivity paper S1.

[0164] exist Figure 6 In (C), Japanese paper S3, an example of highly sensitive paper, is prone to internal voids (gaps) 13. Similar to the case of embossed paper S2, poor transfer is more likely to occur in areas with voids 13 than in areas without voids 13. This is not limited to Japanese paper; poor transfer is also more likely to occur in low-density recording paper S that has internal voids.

[0165] Therefore, when using high-sensitivity paper, there is a problem with toner being difficult to transfer. Transfer is the phenomenon in which toner held on the intermediate transfer belt B by electrostatic forces, adhesive forces, etc., moves to the recording paper S. However, if the adhesion of the toner to the intermediate transfer belt B is weakened, it is easily transferred.

[0166] The present inventors have conducted research and discovered that transferability is improved by applying a developer to the image-forming area of ​​the intermediate transfer belt B using a toner supply image 1 in advance. The detailed mechanism is unclear, but it is believed that silicone oil, an example of a release component contained in the developer, is supplied to the intermediate transfer belt B. It is believed that when the image (print image) to be transferred to the recording paper S is formed on the surface of the silicone oil adhered to the intermediate transfer belt B, the silicone oil weakens the adhesion between the developer constituting the print image and the intermediate transfer belt B, thereby improving transferability even for highly sensitive paper.

[0167] Therefore, in Example 1, when a print instruction is received to use high-sensitivity paper as recording paper S, a toner supply image 1 is formed before the image to be transferred to the recording paper S (the image to be transferred to the medium) is formed. This weakens the adhesion between the printed image transferred to the recording paper S and the intermediate transfer belt B. Consequently, transfer defects are suppressed compared to conventional configurations that do not pre-form the toner supply image 1.

[0168] (Experimental example)

[0169] Next, an experiment was conducted to confirm the effects of the present disclosure.

[0170] (Experimental Example 1)

[0171] In Experimental Example 1, the adhesion of the developer was measured on the image portion where an image was formed and the non-image portion where an image was not formed on the intermediate transfer belt B. In the experiment, the adhesion was measured without forming a toner supplied image 1 (before the recovery mode), and after forming a toner supplied image 1 on both the image portion and the non-image portion (after the recovery mode in ST12 and ST13).

[0172] Adhesion force is measured using the air pressure (wind pressure) as an adhesion force index (Pa): while the developer is attached to the intermediate transfer belt B, the intermediate transfer belt B is stopped, air is blown toward the developer, and the developer is visually dispersed by the blown air.

[0173] Figure 7 The experimental results are shown in .

[0174] Figure 7 This is a graph showing the experimental results of the adhesion of the developer to the intermediate transfer belt, with the vertical axis representing the adhesion.

[0175] exist Figure 7Before the recovery mode is executed, the adhesion in the non-image area is high. However, after the recovery mode is executed, in which toner is supplied to the image 1, the adhesion decreases. Furthermore, in the image area, the adhesion after the recovery mode is lower than before the recovery mode. Furthermore, after the recovery mode is executed, the difference in adhesion between the image and non-image areas is eliminated.

[0176] Figure 8 This is an explanatory diagram of the relationship between an example of an image intended to be transferred to a medium and a toner supplied image.

[0177] exist Figure 8 In the image area 21 of one page, there are areas 22 to which a developer such as text, a picture, or a photo is transferred, and areas 23 to which a developer is not transferred. In the area 23a to which a developer is not transferred in the previous operation, the image area 21 is formed as follows. Figure 7 The adhesion of the intermediate transfer belt B is high, as in the state of the non-image portion before the recovery mode. Figure 8 In this case, if area 23a, where developer was not transferred in the preceding process, becomes area 22b, where developer is transferred in the subsequent process, the developer's adhesion becomes high, potentially leading to transfer failure. Furthermore, if area 22b', where developer is transferred in the subsequent process, includes area 22b-1' that overlaps with area 22a, where developer was transferred in the preceding process, and area 22b-2' that overlaps with area 23a, where developer was not transferred in the preceding process, then, if recovery mode is not executed, localized transfer failure may occur due to the difference in adhesion, potentially leading to noticeable image quality defects.

[0178] On the other hand, in the present application, when high-sensitivity paper is used in the subsequent job, the toner supply image 1 is formed before the subsequent job. Figure 7 As after the recovery mode, the subsequent job is executed in a state where the adhesion of the developer is reduced and the level difference is eliminated. Therefore, it is possible to suppress transfer failure in the subsequent job using high-sensitivity paper.

[0179] Furthermore, in Example 1, forming the toner supply image 1 using high-sensitivity paper can suppress overall developer consumption compared to forming the toner supply image 1 even on low-sensitivity paper where the necessity for forming the toner supply image 1 is low.

[0180] Furthermore, in Example 1, a toner supply image 1 is formed not only when using high-sensitivity paper, but also every time a specified number of pages are printed. Therefore, even if the developer's adhesion increases as the image is formed, the adhesion can be reduced again by forming the toner supply image 1. This allows for stable transfer suppression in both the early and late stages of printing, even when printing multiple pages continuously. Furthermore, the formation of the toner supply image 1 can be executed by inputting the recovery mode start button UIc. Therefore, if the user wishes to confirm the printed image quality and enter recovery mode, they can manually start the process. This allows for more flexible response to user needs, compared to situations where manual initiation is not possible.

[0181] Furthermore, in Example 1, an image covering the entire image area 2 is used as the toner supply image 1. Therefore, there is no need to consider areas 22 to which the image will be transferred or areas 23 to which the image will not be transferred in previous or subsequent operations. This reduces the processing load compared to storing and calculating the values ​​of each area 22 and 23. Furthermore, regardless of the frequency or size of each area 22 and 23, the adhesion force of the entire image area 2 can be stably reduced.

[0182] Furthermore, in Example 1, the toner supply image 1 is formed during multiple turns of the intermediate transfer belt B. While the developer release component may be insufficiently supplied with only one turn of the intermediate transfer belt B, sufficient supply of the release component is achieved by supplying the toner supply image 1 over multiple turns. Consequently, transfer defects can be stably suppressed.

[0183] Furthermore, in Example 1, the toner supply image 1 is also formed at the position corresponding to the inter-image area 3 while the intermediate transfer belt B rotates multiple times. Therefore, the adhesive force can be uniformly reduced over the entire surface of the intermediate transfer belt B.

[0184] (Change Example)

[0185] Figure 9 is an explanatory diagram of an example of a change in a toner supply image. Figure 9 (A) is an explanatory diagram of a state in which a toner supply image corresponds to the entire image to be transferred. Figure 9 (B) is an explanatory diagram of a case where a toner supply image is formed at a position different from the image to be transferred. Figure 9 (C) is an explanatory diagram of a case where a toner supply image corresponds to a portion of an image to be transferred.

[0186] In the above-described first embodiment, the toner supplied image 1 is exemplified as an image covering the entire image area 2 , that is, an image covering the entire area of ​​the image to be transferred, but the present invention is not limited thereto.

[0187] like Figure 9 As shown in (A), it is also possible to set a toner supply image 36 in which a developer is supplied to a position 37 corresponding to the entire image portion 32 in the image 31 of the subsequent job. Figure 9 The toner supply image 36 of (A) can suppress the adhesion of the developer to the image portion 32, which could cause image quality problems if a transfer failure occurs. Therefore, there are no problems with the image transferred to the recording paper S. Furthermore, compared to the case of Example 1, the amount of developer used to form the toner supply images 1 and 36 can be reduced.

[0188] exist Figure 9 In (B), a toner supply image 36' can be configured to supply developer to a position 38 different from the image portion 32 in addition to the position 37 corresponding to the entire image portion 32 in the image 31 of the subsequent job. For example, a toner supply image 36' can be formed that supplies developer to a position 38 different from the image portion 32 in the event that the adhesion becomes too high, such as when an image is not formed at the position 38 for a long time in the previous job, and thus the adhesion may not be completely suppressed by applying the toner supply image 1 once. This configuration can prevent the adhesion of the developer from becoming too high.

[0189] exist Figure 9 In (C), it is also possible to configure a toner supply image 36" such that developer is supplied only to a portion of a position 37 corresponding to the image portion 32 in the image 31 of the subsequent operation. That is, it is also possible to configure a toner supply image 36" having a position 37" to which developer is not supplied even if it corresponds to the image portion 32. For example, in a case where the image is continuously formed at the position 37" in the past operation and the adhesion is sufficiently reduced, there is a high possibility that it is useless even if developer is supplied to the position 37". Therefore, it is also possible to configure a toner supply image 36" such that developer is not supplied to such a position 37". By configuring in this way, it is possible to suppress useless consumption of developer.

[0190] (Change Example)

[0191] While the embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the embodiments described above, and various modifications are possible within the scope of the gist of the present disclosure as described in the claims. Modifications (H01) to (H05) of the present disclosure are exemplified below.

[0192] (H01) While the above embodiment illustrates a copy machine U as an example of an image forming apparatus, the present invention is not limited thereto and can be applied to a fax machine or a multifunction peripheral having multiple functions such as a fax machine, a printer, and a copy machine. Furthermore, the present invention is not limited to a multi-color image forming apparatus and can also be configured as a monochromatic image forming apparatus.

[0193] (H02) In the above-described embodiments, the specific numerical values ​​exemplified can be appropriately changed according to changes in design or specifications.

[0194] (H03) While the above embodiment illustrates the case where the toner supply image 1 is formed when using high-sensitivity paper, the present invention is not limited to this. The toner supply image 1 can also be formed when using low-sensitivity paper. Furthermore, in cases where the developer's adhesion increases, such as in high humidity or when the proportion of degraded developer increases, or when image retention elements such as the intermediate transfer belt B degrade over time, the toner supply image 1 can also be formed based on an image from a subsequent job.

[0195] (H04) In the above embodiment, the recovery mode for forming the toner supply image 1 is executed by inputting the recovery mode start button UIc. However, the recovery mode can be executed without providing the recovery mode start button UIc.

[0196] (H05) In the above embodiment, as an example of a toner supply image, it is not limited to Figure 4 or Figure 9 The configurations illustrated in (A) to (C) of FIG. For example, if the image portion is text, the following modifications can be made as appropriate: a rectangular image surrounding the text; an image slightly larger than the image portion 32; or an image having a specific shape, such as a circle or polygon, encompassing the image portion. Furthermore, the color and density can also be modified as appropriate.

Claims

1. An image forming apparatus comprising: an image holding unit that holds an image formed by a developer, the image being an image intended for transfer to a medium and an image not intended for transfer to a medium; a transfer unit that transfers the image to the medium for the purpose of transferring it to the medium; as well as a forming unit that, upon receiving a print instruction to form an image to be transferred to the medium on the image holding unit, forms an image not to be transferred to the medium before at least one of the images to be transferred to the medium at a position on the image holding unit where the image to be transferred to the medium is to be formed; The forming unit has gaps between images not intended to be transferred to the medium in the rotation direction of the image holding unit. The forming unit forms an image not intended to be transferred to the medium while the image holding unit rotates a plurality of times. The forming unit forms an image not intended to be transferred to the medium in an area overlapping with the gap in the next and subsequent rotations of the image holding unit, at a position offset by a specified distance from the position of the image not intended to be transferred to the medium in the previous rotation.

2. The image forming apparatus according to claim 1, wherein An image not intended for transfer to the medium is a halftone image.

3. The image forming apparatus according to claim 1 or 2, wherein: The forming unit includes: a first forming mode for a first medium; and a second forming mode for a second medium having a transfer sensitivity lower than that of the first medium. In the first formation mode, before the image intended for transfer to the medium is formed on the image holding unit, an image not intended for transfer to the medium is formed at a position on the image holding unit where the image intended for transfer to the medium is formed.

4. The image forming apparatus according to claim 3, wherein The first medium includes embossed paper or Japanese paper.

5. The image forming apparatus according to claim 4, wherein The second medium includes thin paper, plain paper, thick paper, or coated paper.

6. The image forming apparatus according to claim 1, wherein The image forming apparatus includes an input unit through which a user can input an instruction for executing an operation of forming an image that is not intended to be transferred to the medium on the image holding unit.

7. The image forming apparatus according to claim 1, wherein The image not intended to be transferred to the medium has a predetermined length along the rotation direction of the image holding unit.

8. The image forming apparatus according to claim 1, wherein The forming unit forms an image not intended for transfer to the medium corresponding to a portion of the image intended for transfer to the medium.

9. The image forming apparatus according to claim 1, wherein The forming unit forms an image not intended for transfer to the medium corresponding to the entire image intended for transfer to the medium.

10. The image forming apparatus according to claim 8 or 9, wherein An image not intended to be transferred to the medium is also formed at a position different from the image intended to be transferred to the medium.

11. The image forming apparatus according to claim 1, wherein The forming unit forms an image not intended for transfer to the medium covering an entire region where the image intended for transfer to the medium can be formed.

Images