JP2010184415A - Image forming apparatus, image forming method of image forming apparatus, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent clogging of a nozzle due to drying of ink. <P>SOLUTION: An image forming apparatus comprises: an ink usage amount adjusting means for adjusting the usage amounts of black ink and color inks; and an image plotting means for plotting a monochromatic image by using the inks adjusted by the ink usage amount adjusting means, wherein the ink usage amount adjusting means adjusts the usage amounts of each color ink on the basis of characteristics of each color ink to be used and usage environment so as not to clog the nozzle due to the drying of each color ink. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus that adjusts the amount of ink used to prevent clogging of nozzles due to drying of ink, an image forming method thereof, and a program therefor.

  An ink jet recording apparatus employing an ink jet recording method is capable of recording with high image quality and is relatively inexpensive, and is widely used as a color image output device with the spread of personal computers. ing.

  An ink jet recording head used in an ink jet recording apparatus includes a plurality of nozzles in the sub-scanning direction (paper traveling direction) and is moved in the main scanning direction (direction orthogonal to the paper traveling direction) by a carriage mechanism. . Each nozzle ejects ink droplets at a timing according to the dot pattern data obtained by developing the recording data. Thereby, ink droplets from each nozzle adhere to the recording medium (paper), and printing is performed.

  Such an ink jet recording apparatus has rapidly become popular for personal use because it has low price and high image quality when using special paper. Recently, however, it has recently been an electrophotographic laser printer. Is used as a recording apparatus capable of color output even in ordinary paper recording in offices.

  In the inkjet recording apparatus capable of recording a color image, a method of using only K ink is generally used when recording a monochrome image. However, in a nozzle of a color recording head that is not used during monochrome image recording, In the vicinity of the ink, drying proceeds and clogging is likely to occur. In order to prevent this, it is necessary to frequently perform a maintenance operation, which greatly affects the recording speed and cost.

  Therefore, for example, Patent Document 1 discloses an invention in which color ink is prevented from being clogged by recording a combination of K ink and color ink during monochrome image recording.

  As described above, the method described in Patent Document 1 can prevent nozzle clogging as the amount of color ink used increases when black is recorded using both K ink and color ink. However, the side effect is that the recorded black is colored or the printing cost increases due to the large amount of ink used. Conversely, if the amount of color ink used is too small, nozzle clogging cannot be prevented.

  Therefore, when recording black using both K ink and color ink, it is important to adjust the amount of color ink used. However, ink drying properties vary depending on the components of the ink, and because it is strongly affected by temperature, humidity, etc., it is highly dependent on the usage environment, so the amount of color ink used is suitable for black recording. There was a problem that it was difficult to determine uniquely.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to prevent nozzle clogging due to drying of ink.

  In order to solve the above problems, an image forming apparatus according to the present invention uses an ink usage amount adjusting unit that adjusts the usage amount of black ink and color ink, and a monochrome image using the ink adjusted by the ink usage amount adjustment unit. An image drawing means for drawing on a recording medium, and the ink use amount adjusting means uses each color ink based on characteristics and use environment of each color ink so that the nozzle is not clogged by drying each color ink. It is characterized by adjusting the amount.

  An image forming method according to the present invention includes: an ink usage adjustment step that adjusts the usage amounts of black ink and color ink; and image drawing that draws a monochrome image on a recording medium using the ink adjusted by the ink usage adjustment step. And the step of adjusting the ink usage amount adjusts the usage amount of each color ink based on the characteristics of each color ink used and the usage environment so that the nozzles are not clogged due to drying of each color ink. And

  The program according to the present invention includes an ink use amount adjustment process for adjusting the use amounts of black ink and color ink, and an image drawing process for drawing a monochrome image on a recording medium using the ink adjusted by the ink use amount adjustment process. In the ink usage adjustment process, the computer adjusts the usage amount of each color ink based on the characteristics and usage environment of each color ink so that the nozzles are not clogged by drying each color ink. It is characterized by making it.

  According to the present invention, it is possible to prevent clogging of nozzles due to drying of color ink by adjusting the amount of color ink used suitable for the use environment.

It is a schematic perspective view which shows the mechanism part of the inkjet recording device which concerns on embodiment of this invention. FIG. 2 is a diagram illustrating a schematic configuration example of a head unit mounted on an ink jet recording apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a schematic configuration example of a recording head according to an embodiment of the invention. It is a figure for demonstrating the operation example of the head unit at the time of recording on the recording medium which concerns on embodiment of this invention. 2 is a block diagram of a schematic configuration example of a control unit of the image forming apparatus according to the embodiment of the present disclosure. FIG. FIG. 3 is a diagram illustrating an example of a print control unit and a head driver according to an embodiment of the present invention. It is the figure which showed an example of the drive waveform which concerns on embodiment of this invention. It is the figure which showed an example of the drive waveform which concerns on embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 shows an example of an ink jet recording system according to an embodiment of the present invention.

  In FIG. 1, the recording system is mainly composed of an inkjet recording apparatus 100 and a host computer 101 such as a personal computer.

  The ink jet recording apparatus 100 is of a serial type, and a carriage 4 is movably mounted on guide rails 2 and 3 laid horizontally on the frame 1. A recording head 5 is mounted on the carriage 4, and a motor or the like (not shown) is used. The carriage 4 can be moved in the direction of arrow A by the drive source.

  A sheet 7, which is a printing medium set on the guide plate 6, is taken in by a platen 10 that is rotated via a drive gear 8 and a sprocket gear 9 by a drive source (not shown), and is pressed against the peripheral surface of the platen 10. The pressure roller 11 can be conveyed in the direction indicated by the arrow B. The platen 10 can also be manually rotated by the feed knob 10a. Then, while moving and scanning the print head 5 (carriage 4) in the main scanning direction (arrow A direction), the paper 7 is transported in the sub-scanning direction (arrow B direction) and ink droplets are ejected from the print head 5. The image is printed on the paper 7.

  FIG. 2 is a diagram illustrating a schematic configuration example of a head unit mounted on the color inkjet recording apparatus according to the embodiment of the present invention.

  In FIG. 2A, the head unit 5 is composed of ejection units 12 and 13 corresponding to the respective colors. Usually, recording is performed by ejecting ink droplets onto the paper surface from the head unit 5 in which the ejection units 12 and 13 are integrated. Each of the ejection units 12 and 13 has a plurality of ink ejection nozzles, and can eject a plurality of sizes of ink (pigment-based inks) having different droplet amounts. The recording head 5 can also be configured using a single inkjet head that ejects ink droplets of a plurality of colors.

  In the above description, the color ink jet recording apparatus 100 that discharges liquid ink is described as a representative example. However, as the discharge mechanism, a film that uses a piezoelectric effect by a piezoelectric element or a film that includes a heating element that generates heat when energized. An apparatus that uses a boiling type, or an electrostatic image forming apparatus that pressurizes the ink liquid chamber by displacing the diaphragm with an electrostatic force between the diaphragm and an electrode facing the diaphragm may be applied.

  FIG. 2B shows how ink droplets ejected from the head unit 5 are recorded on the recording paper 7.

  FIG. 3 is a diagram illustrating an arrangement example of nozzles in the head unit of the color inkjet recording apparatus according to the embodiment of the present invention. As shown in FIG. 3, each of the ejection units 12 and 13 constituting the head unit 5 is a nozzle constituted by a plurality of nozzles 18n that eject droplets arranged in a direction perpendicular to the main scanning direction. Rows N1 and N2 are arranged side by side in the main scanning direction.

  FIG. 4 is a diagram for explaining an operation example of the head unit at the time of bidirectional recording on a recording sheet according to the embodiment of the present invention. In FIG. 4, the head unit 5 has ejection units 12 and 13 arranged in the order of black, cyan, magenta, and yellow (hereinafter referred to as K, C, M, and Y) in the main recording forward recording direction. Yes. The color inkjet recording apparatus 100 reciprocates such a head unit 5 in the main scanning direction, and performs printing (injecting ink droplets from the nozzles) both when moving in the forward direction and when moving in the backward direction.

  The order of colors and the number of colors in the head unit 5 are not necessarily limited to this example. For example, a different arrangement order or more colors may be handled depending on the ink characteristics, the design concept, or the like. For example, other combinations capable of expressing black by color mixture such as R, G, and B can be used.

  In the above description, an example has been shown in which printing is performed both in the forward direction and in the backward direction in the reciprocating movement of the head unit 5 in the main scanning direction, but in the forward direction or in the backward direction. Printing may be performed at either one of the times.

  As for the ink, not only pigment-based ink but also dye-based ink may be used. Furthermore, although the case where the head unit 5 is a serial head has been described above, a line head may be used as the head unit 5.

  Next, a method of using K ink and color ink together in order to prevent nozzle clogging when recording black using an ink jet recording apparatus according to an embodiment of the present invention will be described.

  Generally, when black (black) is expressed by mixing color inks of cyan (C), magenta (M), and yellow (Y), black is obtained by mixing approximately equal amounts (equivalent drops). (Composite black) can be expressed. Although it is related to the type and constituent components of the ink, when expressing black having a different color tone, the mixing ratio of the three inks is changed. Black (real black) can also be expressed by mixing black (K) with a mixture of the above three inks.

  Regarding the relationship between the droplet sizes of the K ink and the color ink, the smaller the color ink is, the fewer the side effects that are colored by the color ink combined with the recorded black.

  In addition, the number of droplets of K ink and color ink is less when the color ink is smaller than the K ink.

  However, when the color ink droplet size or the number of droplets is small or too small, or the longer the time for recording black with only K ink, the longer the nozzle that discharges the color ink is left unused. As a result, the ink near the nozzles is dried and clogged.

  However, the optimal ink usage varies depending on the ink characteristics (drying properties) of each ink component and the environment (temperature, humidity) in which the ink jet recording device is used. Use ink according to these conditions. It is desirable to vary the amount. For example, if the ink is generally easy to dry, the amount used may be large, and if the ink is difficult to dry, the amount used is preferably small. When the temperature is high, the ink is easy to dry, and when the temperature is low, the ink is difficult to dry. If the humidity is high, the ink is difficult to dry, and if the humidity is low, the ink is likely to dry. The amount of ink used is adjusted according to the above conditions.

  The above-described ink characteristic is the ink drying property. In addition, the use environment that affects the temperature and humidity is preferably detected by a sensor in the vicinity of the recording head.

  Furthermore, from the standpoint of image quality, since the optimum ink usage varies depending not only on the temperature and humidity but also on the type of recording medium, the ink usage may be selected depending on the type of recording medium.

  At this time, the user may select the type of the recording medium and select an appropriate ink usage amount, or the sensor may automatically identify the type of the recording medium and select the appropriate ink usage amount. . For example, when the ink absorption characteristic of the recording medium is easy to absorb ink, the amount used is large, and when it is difficult to absorb ink, the amount used is small. However, since various conditions such as ink absorption characteristics, moisture absorption state, thickness, and ink drying conditions of the recording medium are combined, it is desirable to appropriately adjust the amount of ink used. However, when the amount of ink used is large, the maximum ink ejection amount per unit area of the recording medium is not exceeded.

  Further, since the use environment (temperature, humidity) varies depending on the region where the ink jet recording apparatus is used, the color ink usage amount may be set according to the sales region, or the region used by the user may be set. For example, a small amount of ink may be set in a region where the ink is difficult to dry in a region where the temperature is low, or a large amount of ink may be set in a region where the ink is likely to dry even if the temperature is low. Also, the amount of ink used may be set lower in areas where the temperature is high and the ink is difficult to dry, or may be set higher in areas where the temperature is high and the ink tends to dry.

  As a method of adjusting the ink usage described above, the ink droplet size may be changed. For example, the ink droplet size may be increased when the usage amount is increased, and the ink droplet size may be decreased when the usage amount is decreased. The number of drops may be adjusted by changing the error diffusion or the input value to the dither mask. For example, the number of drops is decreased when the error diffusion or the input value to the dither mask is increased, and the number of drops is increased when the input value is decreased. Further, as an adjustment method, the reverse case described above can be considered. That is, the number of drops may be increased when the input value is increased, and the number of drops may be decreased when the input value is decreased.

  Further, in the case where the black recording image using the K ink and the color ink using the automatically adjusted color ink usage amount does not meet the user's preference, the user can set an arbitrary ink usage amount. Good.

  At this time, the usage amount of K ink and the usage amount of color ink have an inversely proportional relationship.

  Further, in order to prevent nozzle clogging when recording black using an ink jet recording apparatus, the method of using K ink and color ink in combination with a method of expressing black by mixing color ink and black ink The method of expressing black by mixing color ink and color ink may be switched and recorded for each predetermined number of sheets so that the ink does not dry. In addition, the color ink is mixed to express black, the black ink and color ink are mixed to express black, and the method using only black ink is switched for each number of sheets so that the ink does not dry. May be recorded.

  Next, FIG. 5 is a block diagram of a schematic configuration example of the control unit of the image forming apparatus according to the embodiment of the present invention.

  The control unit 200 of the image forming apparatus according to the present embodiment also includes a CPU 201 that controls the entire image forming apparatus that also serves as a means for correcting the outline (for example, a means for performing jaggy correction), and a book executed by the CPU 201. Program including the program according to the embodiment, ROM 202 for storing other fixed data, RAM 203 for temporarily storing image data and the like, and rewritable data for holding data even while the power of the image forming apparatus is shut off A non-volatile memory 204 and an ASIC (Application Specified IC) 205 that processes input / output signals for controlling various kinds of signal processing and rearrangement of image data and other image forming apparatuses are provided. .

  The control unit 200 also includes an I / F 206 for transmitting and receiving data and signals to and from the host, data transfer means for driving and controlling the recording head 5, and drive waveform generation means for generating a drive waveform. A printing control unit 207, a head driver (driver IC) 208 for driving the recording head 5 provided on the carriage 3, a motor driving unit 210 for driving the main scanning motor 220 and the sub scanning motor 222, and charging An AC bias supply unit 212 that supplies an AC bias to the roller 34, detection signals from the encoder sensors 221, 223, and various sensors such as a temperature sensor 215 that detects an environmental temperature as a factor causing a shift in the dot formation position. An I / O 213 for inputting a detection signal is provided. The control unit 200 is connected to an operation unit 214 for inputting and displaying information necessary for the image forming apparatus.

  Here, the control unit 200 transmits image data from the host side such as an information processing device such as a personal computer, an image reading device such as an image scanner, an imaging device such as a digital camera, etc. via an I / F 206 via a cable or a network. Receive.

  Then, the CPU 201 of the control unit 200 reads and analyzes the print data in the reception buffer included in the I / F 206, performs necessary image processing, data rearrangement processing, and the like in the ASIC 205, and prints the image data. The data is transferred from the unit 207 to the head driver 208. Note that generation of dot pattern data for outputting an image is performed by a printer driver on the host side as will be described later.

  The print control unit 207 transfers the above-described image data to the head driver 208 as serial data, and transmits a transfer clock, a latch signal, a droplet control signal (mask signal), and the like necessary for the transfer of the image data and confirmation of the transfer. In addition to the output to the head driver 208, a drive waveform generator and head driver composed of a D / A converter, a voltage amplifier, a current amplifier, etc. for D / A converting the pattern data of the drive signal stored in the ROM 202 Drive waveform selection means for supplying to the head driver 208, and generating a drive waveform composed of one drive pulse (drive signal) or a plurality of drive pulses (drive signal).

  The head driver 208 selectively selects a drive signal constituting a drive waveform supplied from the print control unit 207 based on image data corresponding to one line of the print head 5 inputted serially, as a droplet of the print head 5. The recording head 5 is driven by applying it to a driving element (for example, a piezoelectric element as described above) that generates energy for discharging the ink. At this time, by selecting a driving pulse constituting the driving waveform, for example, dots having different sizes such as large droplets (large dots), medium droplets (medium dots), and small droplets (small dots) can be distinguished. it can.

  The CPU 201 also detects a speed detection value and a position detection value obtained by sampling a detection pulse from the encoder sensor 221 constituting the linear encoder, and a speed target value and a position target value obtained from a previously stored speed / position profile. Based on this, a drive output value (control value) for the main scanning motor 220 is calculated, and the main scanning motor 220 is driven via the motor driving unit 210. Similarly, based on the speed detection value and position detection value obtained by sampling the detection pulse from the encoder sensor 223 constituting the rotary encoder, and the speed target value and position target value obtained from the speed / position profile stored in advance. Then, a drive output value (control value) for the sub-scanning motor 222 is calculated, and the sub-scanning motor 222 is driven via the motor driving unit 210.

  Next, FIG. 6 is a diagram illustrating an example of a print control unit and a head driver.

  As described above, the print control unit 207 generates a drive waveform (common drive waveform) composed of a plurality of drive pulses (drive signals) within one printing cycle, and outputs a print waveform. And a data transfer unit 302 that outputs a clock signal, a latch signal (LAT), and droplet control signals M0 to M3.

  The drop control signal is a 2-bit signal that instructs each drop to open and close an analog switch, which will be described later, of the head driver 208. The drop control signal is a waveform to be selected according to the print cycle of the common drive waveform. The state transitions to (ON), and when not selected, the state transitions to L level (OFF).

  The head driver 208 receives a transfer clock (shift clock) and serial image data (gradation data: 2 bits / CH) from the data transfer unit 302, and each register value of the shift register 311 by a latch signal. A latch circuit 312 for latching, a decoder 313 that decodes gradation data and droplet control signals M0 to M3 and outputs the result, and a logic level voltage signal of the decoder 313 is converted to a level at which the analog switch 315 can operate. Level shifter 314, and an analog switch 315 that is turned on / off (opened / closed) by the output of the decoder 313 provided via the level shifter 314.

  The analog switch 315 is connected to the selection electrode (individual electrode) of each piezoelectric element 121, and the common drive waveform from the drive waveform generation unit 301 is input thereto. Therefore, by turning on the analog switch 316 in accordance with the result of decoding the serially transferred image data (gradation data) and the control signals MN0 to MN3 by the decoder 313, a required drive signal constituting the common drive waveform is obtained. Passing (selected) is applied to the piezoelectric element 121.

  Next, an example of the drive waveform will be described with reference to FIGS.

  As shown in FIG. 7, the drive waveform generation unit 301 includes a waveform element that falls from the reference potential Ve and a waveform element that rises from the state after the fall within one printing cycle (one drive cycle). A drive signal (drive waveform) composed of eight drive pulses P1 to P8 is generated and output. On the other hand, the driving pulse to be used is selected by the droplet control signals M0 to M3 from the data transfer unit 302.

  Here, the waveform element in which the potential V of the drive pulse falls from the reference potential Ve is a pull-in waveform element in which the piezoelectric element 121 contracts and the volume of the pressurized liquid chamber expands. Further, the waveform element that rises from the state after the fall is a pressurizing waveform element that causes the piezoelectric element 121 to expand and the volume of the pressurized liquid chamber to contract.

  Then, when a small droplet (small dot) is formed by the droplet control signals M0 to M3 from the data transfer unit 302, the drive pulse P1 is selected as shown in FIG. 8A, and the medium droplet (medium dot) is selected. When forming, drive pulses P4 to P6 are selected as shown in FIG. 8B, and when forming large droplets (large dots), drive pulses P2 to P8 are selected as shown in FIG. 8C. When fine driving is performed (for example, when the meniscus is vibrated without droplet ejection), the fine driving pulse P2 is selected and applied to the piezoelectric element 121 of the recording head 5 as shown in FIG. To.

  The image forming method using the ink jet recording apparatus according to the embodiment of the present invention has been mainly described above. However, the application of the present invention is not limited to such a configuration. Either of the image forming apparatuses may be provided.

  Further, the present invention may be in the form of a program for causing a computer to execute the above-described image forming method, or in the form of a computer-readable recording medium on which the program is recorded. Here, the program includes a printer driver that can be incorporated into a computer.

  An embodiment of a recording medium storing a program and data for realizing an image forming method according to an embodiment of the present invention will be described. Specifically, a CD-ROM, a magneto-optical disk, a DVD-ROM, an FD, a flash memory, a memory card, a memory stick, and various other ROMs and RAMs can be assumed as the recording medium. By causing a computer to execute the steps in each embodiment of the present invention and recording and distributing a program for realizing the functions of the above-described image forming method, the functions can be easily realized.

  Then, the recording medium as described above is mounted on an information processing apparatus such as a computer and the program is read by the information processing apparatus, or the program is stored in a storage medium provided in the information processing apparatus. By reading, the function of the image forming method according to the present invention can be executed.

  The ink use amount adjusting means of the image forming apparatus according to the present invention is characterized in that adjustment is made so that a large amount of each color ink that is easily dried is used.

  The ink use amount adjusting means of the image forming apparatus according to the present invention is characterized by adjusting the ink droplet size or the number of ink ejected droplets.

  The ink use amount adjusting means of the image forming apparatus according to the present invention is characterized in that the ink to be used is switched and used for each predetermined number of sheets.

  The characteristic of each color ink of the image forming apparatus according to the present invention is that the ink is dry.

  The use environment of the image forming apparatus according to the present invention is characterized in that the temperature, the humidity, the area where the image forming apparatus is used, and the type of the recording medium.

  An image forming apparatus according to the present invention includes a sensor that detects a use environment, and the ink use amount adjustment unit automatically adjusts the use amount of each color ink based on information on the use environment detected by the sensor. To do.

  The ink use amount adjusting means of the image forming apparatus according to the present invention is characterized in that the use amount and use amount of each color ink set by the user is adjusted in preference to the use amount based on the use environment. To do.

  In addition, according to the embodiment of the present invention, the amount of color ink used is adjusted based on the characteristics or usage environment of each mounted ink, which is optimal for preventing drying of nozzles that discharge color ink. It can be an amount.

  Further, according to the embodiment of the present invention, the optimum amount for preventing drying of the nozzle that discharges the color ink by adjusting the amount of the color ink used in accordance with the temperature of the environment in which the recording apparatus is used. It can be.

  In addition, according to the embodiment of the present invention, by adjusting the amount of color ink used in accordance with the humidity of the environment in which the recording apparatus is used, the optimum amount for preventing drying of the nozzles that discharge the color ink It can be.

  In addition, according to the embodiment of the present invention, by adjusting the amount of color ink used in accordance with the type of recording medium using the recording apparatus, it is optimal for preventing drying of nozzles that discharge color ink. It can be an amount.

  Further, according to the embodiment of the present invention, the usage amount of each ink can be automatically adjusted in accordance with the information on the usage environment detected by the sensor or the type of the recording medium.

  Further, according to the embodiment of the present invention, the usage amount of each ink can be adjusted by adjusting the number of ejected droplets of each ink.

  Further, according to the embodiment of the present invention, the usage amount of each ink can be adjusted by adjusting the size of each ink droplet.

  In addition, according to the embodiment of the present invention, the user can output a black image that prioritizes user preference over prevention of clogging of color nozzles by adjusting the usage ratio of K ink to other inks. it can.

  Although the embodiments have been described above, various modifications and changes can be made to these embodiments and specific examples without departing from the broad scope and scope of the present invention defined in the claims.

DESCRIPTION OF SYMBOLS 100 Inkjet recording device 101 Host computer 1 Frame 2, 3 Guide rail 4 Carriage 5 Recording head 6 Guide plate 7 Recording paper 8 Drive gear 9 Sprocket gear 10 Platen 10a Feed knob 11 Pressure roller 12, 13 Injection unit 18n Nozzle N1, N2 Nozzle Column

Japanese Patent No. 3184744

Claims (10)

Ink usage adjustment means for adjusting the usage of black ink and color ink;
Image drawing means for drawing a monochrome image on a recording medium using the ink adjusted by the ink use amount adjusting means,
The ink use amount adjusting means adjusts the use amount of each color ink based on the characteristics and use environment of each color ink used so that the nozzles are not clogged by drying each color ink. apparatus.   The image forming apparatus according to claim 1, wherein the ink use amount adjusting unit adjusts the ink to be used in a large amount so that the ink is easily dried.   The image forming apparatus according to claim 1, wherein the ink usage amount adjusting unit adjusts the size of ink droplets or the number of ejected droplets of ink.   4. The image forming apparatus according to claim 1, wherein the ink use amount adjusting unit switches and uses ink to be used for each predetermined number of sheets. 5.   The image forming apparatus according to claim 1, wherein the characteristic of each color ink is ink drying.   6. The image forming apparatus according to claim 1, wherein the use environment is temperature, humidity, a local place to be used, and a type of a recording medium. A sensor for detecting the use environment;
The said ink usage-amount adjustment means adjusts the usage-amount of each said color ink automatically based on the information of the said usage environment detected by the said sensor, The any one of Claim 1 to 6 characterized by the above-mentioned. Image forming apparatus.   The ink use amount adjusting unit adjusts the use amount of each color ink in preference to the use amount based on the use environment with respect to the use ratio and use amount of each color ink set by a user. The image forming apparatus according to any one of 1 to 7. An ink usage adjustment step for adjusting the usage of black ink and color ink;
An image drawing step of drawing a monochrome image on a recording medium using the ink adjusted in the ink usage adjustment step,
The ink use amount adjusting step adjusts the use amount of each color ink based on the characteristics and use environment of each color ink to be used so that the nozzles are not clogged by drying each color ink. Image forming method of apparatus. An ink usage adjustment process for adjusting the usage of black ink and color ink;
An image drawing process for drawing a monochrome image on a recording medium using the ink adjusted by the ink usage adjustment process,
The ink use amount adjustment process is a program that causes a computer to adjust the use amount of each color ink based on the characteristics and use environment of each color ink to be used so that the nozzles are not clogged by drying each color ink. .

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