JP2020069643A - inkjet printer - Google Patents

Abstract

To reduce scattering of ink mist and paper dust that occur when printing with an inkjet printer to reduce adhesion to a nozzle plate.SOLUTION: An inkjet printer controls potentials of a nozzle plate 181 and a cover head 183 to be GND potential and forms a non-uniform electric field between a short side electrode 126 of a platen member 100 and the nozzle plate and the cover head, thereby causing an absorption member 110 of the platen member 100 to efficiently adsorb ink mist and paper dust.SELECTED DRAWING: Figure 8

Description

  The present invention relates to an inkjet printer capable of avoiding or suppressing adhesion of ink mist and paper dust to a nozzle plate in an inkjet printer.

  When printing with an inkjet printer, especially during borderless printing, since the ink is sprayed to the outside of the edge of the paper that is the print target, the ink droplets that did not reach the paper become mist, and The inner wall of the device housing of the printer, the internal circuit board, the outer wall of the device housing, and the periphery of the desk or the like where the device is placed may be contaminated. As a countermeasure against this, for example, a method disclosed in Japanese Patent Laid-Open No. 2004-242242 has been adopted in which an electric field is generated between a nozzle plate of a head for ejecting ink and a platen member to reduce the floating of the ink mist. ..

  The inkjet printer also performs a flushing operation to clean the nozzle openings of the nozzle plate. Since ink mist is also likely to occur during this flushing, for example, as disclosed in Patent Document 2, a method of generating an electric field between the nozzle plate and the cap member to reduce floating of the ink mist. Was taken.

JP, 2004-202867, A JP, 2012-240257, A

  However, the conventional method has the following problems. First, a part of the ink droplets ejected from the nozzle plate plate becomes mist (droplet having a diameter smaller than that of the ink droplet for the original printing), returns to the nozzle plate side, and adheres to it. There was a problem that the image quality is deteriorated due to aggregation and adhesion to the nozzle openings. A similar phenomenon occurs during flushing, and the mist of ink returns to and adheres to the nozzle plate, which complicates the nozzle plate cleaning process.

  Further, as a problem other than the ink mist, there is the adhesion of paper dust to the printing target paper. Paper dust generated when the paper is cut may adhere to the edge of the paper, and when printing with an inkjet printer, the paper dust becomes dust due to vibration during paper transport by the device. Is released into. Some of the ejected paper powder adheres to the nozzle plate, and when adhered to the nozzle opening, it becomes an obstacle to the nozzle opening, resulting in a problem that the print image quality is deteriorated.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an inkjet printer that reduces ink mist and paper dust from paper.

[Application example 1]
An ink jet printer that ejects ink from a nozzle plate having a nozzle opening to form an image on a print target, the ink discharge including the nozzle plate on the back side of the print target during image printing processing. The electrode of the platen member arranged in a region facing the head and in a region where ink is ejected to the outside of the print target and receives ink droplets, and the inkjet printer are configured to have a GND potential. An electrode for generating an electric field between the electrode and the metal housing, and when the electrode of the platen member faces the ink ejection surface of the ink ejection head including the nozzle plate, the ink ejection head including the nozzle plate The area of the platen member on the surface facing the electrode is smaller than the area of the ink ejection surface. It is an ink jet printer.

  With this configuration, the ink mist can be effectively attached to the platen side, and it is possible to provide an inkjet printer that can reduce defects due to the ink mist and reduce deterioration of print image quality.

[Application example 2]
The electrode of the platen member has a shape having at least one long-side electrode and a plurality of short-side electrodes, and an interval between the plurality of short-side electrodes is adjusted to each width of a substantially standard paper size. The inkjet printer according to item 1.

  With this configuration, it is possible to effectively reduce the generation of ink mist during borderless printing of standard paper, reduce paper dust from the paper, and provide an inkjet printer that can reduce deterioration in print image quality.

[Application example 3]
The electrode of the platen member has an absorber made of an insulating material on the side facing the ink ejection surface side of the ink ejection head, and the absorber is arranged so as to cover the entire electrode, The inkjet printer described in Examples 1 and 2.

  With this configuration, it is possible to provide an ink jet printer that can avoid discharge due to the application of a high electric field between the nozzle plate and the electrode of the platen member, and can avoid the trouble of the device due to the occurrence of discharge.

[Application example 4]
An inkjet printer that forms an image on a print target by ejecting ink from a nozzle plate having a nozzle opening, having a cap member for flushing the nozzle opening with ink droplets, and the electrode of the cap member is A mechanism for generating a potential difference between the inkjet printer and a metal casing set to the GND potential, and the electrode of the cap member is larger than the area of the ink ejection surface of the nozzle plate. An inkjet printer having an opening of area.

  With this configuration, the ink mist can be effectively attached to the cap side, the effect of flushing can be improved, and an inkjet printer that can reduce deterioration of print image quality can be provided.

[Application example 5]
The electrode of the cap member has an absorber made of an insulating material on the side facing the ink ejection surface side of the ink ejection head, and the absorber is arranged so as to cover the entire electrode. The inkjet printer described in Example 4.

  With this configuration, it is possible to provide an ink jet printer that can avoid electric discharge when a high electric field is applied between the nozzle plate and the electrode of the cap member, and can avoid a malfunction of the device due to occurrence of electric discharge.

FIG. 3 is a perspective view illustrating an appearance of the inkjet printer according to the first embodiment. FIG. 3 is a perspective view illustrating an appearance of a print portion of the inkjet printer. The enlarged view of the platen member of an inkjet printer, and its circumference. The exploded perspective view explaining the composition of the platen member of a 1st embodiment. The disassembled perspective view explaining the structure of the platen member of 2nd Embodiment. FIG. 4B is a cross-sectional view of the platen member taken along line A-A ′ of FIG. FIG. 3 is a diagram showing the ejection surface side of ink droplets of an ejection head. Explanatory drawing showing the unequal electric field between two electrodes. Explanatory drawing showing the behavior of the particle in the space under an unequal electric field. Explanatory drawing showing the state of adsorption | suction of an ink mist and a paper dust to a platen. The exploded perspective view explaining the composition of the cap member. Sectional drawing of the cap member shown as a B-B 'arrow of FIG. Explanatory drawing showing the relationship between a discharge head and a cap member.

A. First embodiment:
Hereinafter, a configuration applied to the inkjet printer I according to the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing the outer appearance of an inkjet printer I, which is an example of the liquid ejection apparatus according to the first embodiment. FIG. 2 is a perspective view showing the external appearance of the printing portion of the inkjet printer I. FIG. 3 is an enlarged view of the platen member 100 of the inkjet printer I according to the present invention and its surroundings. Hereinafter, the inkjet printer I is also referred to as “printer I”.

  As shown in FIG. 2, the printer I of this embodiment is provided with a head unit 1 and a control device 400. The head unit 1 includes an inkjet type ejection head 180, which is an example of a liquid ejection head, and is mounted on the carriage 3. Hereinafter, the inkjet type ejection head 180 is also referred to as “ejection head 180”. The control device 400 controls the overall operation of the printer I. The drive motor 6 transmits a drive force to the carriage 3 via a plurality of gears (not shown) and the timing belt 7. As a result, the carriage 3 having the head unit 1 mounted thereon is reciprocated along the axial direction of the carriage shaft 5 attached to the apparatus main body 4 made of metal.

  The apparatus body 4 is provided with a platen member 100 having a flat plate shape. The platen member 100 supports the paper 150 (a kind of object to be processed) from its back surface and defines the position of the paper 150 with respect to the ejection head 180. Details of the platen member 100 will be described later.

  The inkjet printer I according to the present embodiment further includes a feeding mechanism that intermittently conveys the sheet 150 on which the printing process is performed by the ejection head 180 in the feeding direction orthogonal to the head scanning direction.

  As shown in FIG. 3, the feeding mechanism sandwiches the paper 150 and feeds it onto the platen member 100 along the conveyance direction (feeding direction) F, and the paper feed rollers 14a and 14b arranged to face each other. Paper discharge rollers 13a and 13b arranged to face each other for discharging the printed paper 150 are provided. The paper feed roller 14a and the paper discharge roller 13a are driven rollers, and the paper feed roller 14b and the paper discharge roller 13b are drive rollers.

  In the present embodiment, the direction opposite to the conveyance direction F of the sheet 150 is called the first direction X, and the direction along the moving direction of the carriage 3 is called the second direction Y. In the present embodiment, the relationship in each direction (X, Y, Z) is assumed to be orthogonal, but the arrangement relationship of each configuration is not necessarily limited to be orthogonal. Further, in the present embodiment, the third direction Z is a direction from the paper 150 toward the head unit 1 side, and is a direction opposite to the direction in which the nozzles of the head unit 1 eject ink.

  As shown in FIG. 2, the head unit 1 is connected to a liquid supply means 2 having a liquid storage means such as an ink tank in which liquid ink is stored so as to be able to supply ink. The liquid supply means 2 is fixed to the apparatus main body 4, and the ink from the liquid supply means 2 is supplied to the head unit 1 via a supply tube 2a such as a flexible tube. The liquid supply means 2 is not limited to one fixed to the apparatus main body 4, and, for example, a liquid supply means such as an ink cartridge is held on the head unit 1 so that the liquid supply means together with the head unit 1 is carried by the carriage 3. You may make it move by.

  In the non-printing area of the printer I, a suction device 9 that sucks ink, bubbles, and the like in the flow path from the nozzles of the head unit 1 is provided. The suction device 9 includes a cap member 300 that covers the nozzles of the head unit 1, and a pump 9c that is connected to the cap member 300 via a suction pipe 9b.

  The suction device 9 brings the cap member 300 into contact with the nozzle surface of the head unit 1 in the standby state, and the suction operation of the pump 9c sucks the ink in the flow path of the head unit 1 from the nozzle together with the bubbles. When the printer I is not printing, the nozzle may be sealed by the cap member 300 to prevent the nozzle from drying. The cap member 300 is provided movably along the direction Z in order to contact the nozzle surface and cover the nozzle at a desired timing. The movement of the cap member 300 in the direction Z is performed, for example, by a moving unit such as a drive motor or an electromagnet (not shown).

  Next, details of the platen member 100 will be described with reference to FIGS. 4A and 5. FIG. 4A is an exploded perspective view illustrating the configuration of the platen member 100 of the printer I according to the present invention. FIG. 5 is a cross-sectional view of the platen member 100 showing a cross section in the longitudinal direction of the platen member 100 as seen from the arrow A-A ′ in FIG. 4A. The platen member 100 basically includes three parts, that is, a main body 130, an electrode 120, and an absorbing member 110. The electrode 120 is a ladder-shaped electrode having two long-side electrodes 121 and 122 and a plurality of short-side electrodes 125, 126, 127, 128, 129 sandwiched between them, and is connected to the power source PM by the terminal portion 123.

  FIG. 6 is a view showing the ejection surface side of ink droplets of the ejection head 180 of the printer I according to the present invention. A plurality of nozzle openings 182 are formed in the nozzle plate 181 which serves as an ink ejection portion. A cover head 183 is provided around the nozzle plate 181. The cover head 183 is made of metal, is electrically connected to the GND potential in the circuit of the printer I according to the present invention, and is also electrically connected to the metal casing forming the printer I to have the same potential. There is. The nozzle plate 181 is also preferably connected to the GND potential, but need not be the GND potential.

  Assuming that the area of the cover head 183 including the nozzle plate 181 on the ink ejection surface side is S, the long side electrodes 121 and 122 and the short side electrodes 125 to 129 of the electrode 120 are moved by the movement of the ejection head 180 during the printing operation. It is preferable that the facing area of each of the long-side electrodes 121 and 122 and each of the short-side electrodes 125 to 129 that are covered by the area S when facing each other is sufficiently smaller than the area S.

  The interval between the short-side electrodes 125 to 129 is set according to the length of the standard size paper in the longitudinal direction or the width direction. For example, the interval between the short-side electrodes 125 and 126 is the width and the short side of postcard paper (A6 paper). The electrodes 125 and 127 have a width of B5 paper, the short side electrodes 125 and 128 have a width of A4 paper, the short electrodes 125 and 129 have a width of B4 paper, and the like. Accordingly, when printing each sheet, the short-side electrode 125 and any of the short-side electrodes 126 to 129 can always be present near the edge in the width direction of the sheet. When printing on the paper, the edge of the paper in the longitudinal direction is set to the long side electrode 121 and the timing at which the edge of the paper in the longitudinal direction is placed near the long side electrode 122. It can be made by controlling.

  As shown in FIG. 4A, the electrode 120 is housed in the groove 132 formed in the body 130. The main body 130 is made of an electrically insulating material such as resin. On the upper side of the electrode 120 (the side facing the ejection head 180), the absorbing member 110 for receiving ink droplets or the like is fitted into the recess 131 of the main body 130 so as to cover the electrode 120. The absorbing member 110 is a sponge-like material capable of absorbing ink and is electrically insulating.

  Next, the platen member 200 of 2nd Embodiment is demonstrated using FIG. 4B. FIG. 4B is an exploded perspective view illustrating the configuration of the platen member 200 according to the second embodiment. Regarding the shapes of the electrode 120 and the body 130 corresponding thereto in the first embodiment, as shown in FIG. 4B, the electrode 220 and the body 230 corresponding thereto may be used. More specifically, the electrode has one long side electrode 221 and a plurality of short side electrodes 225, 226, 227, 228, 229, and is connected to the power source PM by the terminal portion 223.

  When the area on the ink ejection surface side of the cover head 183 including the nozzle plate 181 is S, when the ejection head 180 moves during the printing operation, the long side electrode 221 and the short side electrodes 225 to 229 of the electrode 220 face each other. The facing area of each of the long-side electrode 221 and the short-side electrodes 225 to 229 covered by the area S is preferably sufficiently smaller than the area S.

  The interval between the short-side electrodes 225 to 229 is set according to the length of the standard size paper in the longitudinal direction or the width direction. For example, the interval between the short-side electrodes 225 and 226 is the width of the postcard paper (A6 paper) The distance between the side electrodes 225 and 227 is the width of the B5 paper, the distance between the short side electrodes 225 and 228 is the width of the A4 paper, the distance between the short side electrodes 225 and 229 is the width of the B4 paper, and the like. Thus, when printing each sheet, it is possible to always have the short-side electrode 225 or one of the short-side electrodes 226 to 229 near the edge in the width direction of the sheet. When printing on paper, the edge of the paper in the longitudinal direction can be set by controlling the paper feeding mechanism of the printer I at the timing at which the edge of the paper in the longitudinal direction is placed near the long-side electrode 221. it can.

  The electrode 220 is housed in a groove 232 formed in the body 230. The main body 230 is made of a material such as an electrically insulating resin. On the upper side of the electrode 220 (the side facing the ejection head 180), an absorbing member 210 for receiving ink droplets or the like is fitted into the recess 231 of the main body 230 so as to cover the electrode 220. The absorbing member 210 is a sponge-like material capable of absorbing ink and is electrically insulating.

  Next, the principle of mist adhesion will be described with reference to FIGS. 7A and 7B. FIG. 7A is an explanatory diagram showing an unequal electric field between the two electrodes E1 and E2. FIG. 7B is an explanatory diagram showing the behavior of the particles Pc in a space under an unequal electric field. First, an electric field can be formed in the space between the electrodes by facing the two electrodes E1 and E2 and applying a voltage between the two electrodes E1 and E2 using a power source PM. When the areas where E1 and E2 face each other are the same, the formed electric field has a substantially uniform electric field density in the space where the electrodes face each other, and this state is called a uniform electric field. However, when one electrode has a different shape from the other electrode, for example, when the electrode shapes are different, such as the electrode E1 and the electrode E2 shown in FIG. 7A, the electric field is increased from the larger electrode side toward the smaller electrode side. An electric field of increasing density is formed. This state is called an unequal electric field.

  Regarding the behavior of the particles Pc in the space under the non-uniform electric field, as shown in FIG. 7B, the particles Pc are attracted to the electrode E2 side where the electric field density is high. As shown in the figure, this causes dielectric polarization on the surface of the particle Pc due to the external electric field, and electric charges having a polarity that cancels the electric force lines of the electric field are generated. This is because, at this time, the manner in which the electric charges are generated conforms to the bias (nonuniformity) of the lines of electric force.

  In the printer I according to the present invention, an uneven electric field is generated between the surface of the ejection head 180 facing the platen member 100 (ink ejection surface side) and the platen member 100 so that the electric field density is increased on the electrode 120 side of the platen member 100. Is formed. Accordingly, the adsorption of the ink mist on the platen member 100 side can be promoted, and the adhesion to the nozzle plate 181 can be avoided. Further, paper dust that adheres to the edge of the paper and is scattered due to vibration or the like can also be adsorbed to the platen member 100 side, and can be prevented from adhering to the nozzle plate 181.

  The potential of the nozzle plate 181 is preferably GND, which is the same potential as the cover head 183. However, even when the nozzle plate 181 cannot be set to the GND potential, if the surrounding cover head 183 is the GND potential, The cover head 183, the platen member 100, and the lines of electric force of the non-uniform electric field also enter the space on the ink ejection side of the nozzle plate 181, and the ejection head 180 itself moves, so that the effect of adsorbing mist on the platen member 100 side is obtained. Can be demonstrated. The potential of the electrode 120 may be either positive or negative with respect to GND. However, in order to effectively adsorb the ink mist and the paper dust, the voltage of the power source PM applied to the electrode 120 is in the range of several 100V to KV. On the other hand, the distance between the electrode 120 and the nozzle plate 181 or the cover head 183 on the ink ejection side of the GND level (0V) is about 5 mm or less. When a high electric field is formed over a short distance, a discharge may occur. However, in the printer I according to the present invention, since the absorbing member 110 is made of an insulating material and covers the electrodes 120, a discharge is generated due to the formation of a high electric field. Can be avoided. That is, since the electrodes are not exposed to the space, the absorbing member 110 hinders the plasma generation of air generated during discharge. Further, since the absorbing member 110 is insulated from the electrode 120, even if the user's hand or the like approaches the platen member 100 by mistake, an accident such as electric shock can be avoided.

  In the past, the absorbing member 110 was made conductive, but if the absorbing member 110 is made conductive, the voltage applied to the electrode 120 spreads throughout the absorbing member 110 and becomes the same potential. In this situation, an uneven electric field having a higher electric field density is formed on the ink ejection head side than on the absorbing member side, and the ink mist is more likely to be adsorbed on the nozzle plate 181 side.

  Next, the principle of mist adsorption and paper dust adsorption will be described with reference to FIG. FIG. 8 is a diagram for explaining the state of adsorption of ink mist and paper dust on the platen member 100 in the printer I according to the present invention. Ink mist tends to be generated in large quantities during borderless printing. Most of the ink droplets ejected outside the edge of the paper are absorbed by the absorbing member 110, but at the same time, the generation of mist tends to increase.

  Since the short side electrode 126 of the electrode 120 of the printer I according to the present invention is located near the lower side of the edge 151 of the paper 150, the short side electrode 126 is provided between the short side electrode 126 and the nozzle plate 181 and the cover head 183 of the ejection head 180. Since an unequal electric field as shown in the figure can be generated, the generated ink mist is attracted to the platen member 100 side and adsorbed to the absorbing member 110. Further, if there is paper dust on the edge 151 of the paper 150, there is a possibility that the paper dust may be scattered due to vibration of the printer I such as paper conveyance. If the ejection head 180 approaches while the paper dust is floating, the paper dust may adhere to the nozzle plate 181 of the ejection head 180. In the printer I of the present invention, the short-side electrode 126 is arranged near the lower side of the edge 151 of the paper 150, and the short-side electrode 126 is disposed between the short-side electrode 126 and the nozzle plate 181 of the ejection head 180 and the cover head 183. Since such an unequal electric field can be generated, the generated paper dust is attracted to the platen member 100 side and adsorbed to the absorbing member 110. Regarding the edge of the paper 150 in the longitudinal direction, the long edge of the paper 150 is placed on the platen member 100 near the position of the long side electrode 121 or the long side electrode 122 of the platen member 100. If the paper conveyance is controlled and the borderless printing is performed at this position, the ink mist and the paper dust are adsorbed to the absorbing member 110 of the platen member 100, similarly to the borderless printing on the edge of the paper 150 in the width direction. be able to.

  Next, the principle of mist adsorption during flushing will be described with reference to FIGS. 9 to 11. FIG. 9 is an exploded perspective view illustrating the configuration of the cap member 300 of the printer I according to the present invention, and FIG. 10 is a cap member showing a cross section in the longitudinal direction of the cap member 300 as seen from the arrow BB ′ in FIG. 9. FIG. The cap member 300 basically includes three parts, that is, a main body 330, an electrode 320, and an absorbing member 310. The electrode 320 is an electrode having a shape provided with an opening 325, and is connected to the power source PM by the terminal portion 323.

  The electrode 320 is housed in a groove 332 formed in the body 330. Further, the main body 330 has an opening 335 in the center. The main body 330 is made of a material such as an electrically insulating resin. On the upper side of the electrode 320 (the side facing the ejection head 180), an absorbing member 310 for receiving ink droplets, ink mist and the like is fitted into the recess 331 of the main body 330 so as to cover the electrode 320. The absorbing member 310 is a sponge-like material capable of absorbing ink and is electrically insulating.

  FIG. 11 is an explanatory diagram showing the relationship between the ejection head 180 in the home position and the cap member 300 of this embodiment. The cap member 300 of the printer I according to the present invention is at the home position of the ejection head 180, and the main body 330 of the cap member 300 faces the cover head 183 including the nozzle plate 181. In this state, when the ink is blown out (flushing) to improve the state of the nozzle opening 182 of the nozzle plate 181, a negative pressure 340 is applied from the opening 335 of the main body 330 to the ejected ink droplet. The configuration is such that ink droplets do not scatter by flowing a descending air flow.

  Ink mist may also occur during this flushing, and as a countermeasure against this, a voltage is applied between the electrode 320 and the cover head 183 or the like by using the power source PM, and the electrode 320 and the nozzle plate of the ejection head 180 are applied. An unequal electric field in which electric field density increases on the electrode 320 side is formed between the electrode 181 and the cover head 183. Thereby, the ink mist can be effectively absorbed by the absorbing member 310. Further, since the electrode 320 is in a state of being covered by the absorbing member 310 with respect to the ejection head 180 side, it is possible to avoid the occurrence of discharge due to a high electric field between the electrode 320 and the nozzle plate 181 and the cover head 183. Further, since the electrode 320 is not exposed to the space, an accident such as electric shock does not occur even if the user's finger or the like approaches the electrode 320 by mistake.

  Regarding the edges of the respective portions of the electrodes 120, 220 of the platen members 100, 200 and the electrodes 320 of the cap member 300 covered by the respective absorbing members 110, 210, 310, the respective absorbing members 110, 210, 310 are It needs to be covered with 120 and 220 overlapping. This is because if there is no overlap, there is an increased possibility that discharge will occur between the discharge head 180 and the cover head 183 of the nozzle plate 181 that is at the GND potential. The amount of the overlap depends on the voltage applied to the electrodes 120, 220 and 320 and the distances between the electrodes 120, 220 and 320 and the nozzle plate 181 and the cover head 183 of the ejection head 180. When the applied voltage is about 1 KV and each distance is about 3 mm, the amount of overlap is preferably about 1 mm or more.

B. Other forms:
The present disclosure is not limited to the above-described embodiments, and can be realized in various forms without departing from the spirit thereof. For example, the present disclosure can be implemented by the following modes. The technical features in the above embodiments corresponding to the technical features in the embodiments described below are to solve some or all of the problems of the present disclosure, or some or all of the effects of the present disclosure. In order to achieve the above, it is possible to appropriately replace or combine. If the technical features are not described as essential in this specification, they can be deleted as appropriate.

(1) According to one aspect of the present disclosure, there is provided an inkjet printer that forms an image on a print target by ejecting ink from a nozzle plate having a nozzle opening. This inkjet printer is a back surface side of the printing object during image printing processing, a region facing the ink ejection head including the nozzle plate, and the outside of the printing object, ink is ejected, The platen member has a mechanism for generating an electric field between an electrode of a platen member arranged in a region to be covered with ink droplets and a metal casing constituting the inkjet printer and set to a GND potential. Area of the electrode of the platen member opposite to the ink ejection surface of the ink ejection head including the nozzle plate, when compared with the area of the ink ejection surface of the ink ejection head including the nozzle plate. Has a small relationship.
According to the inkjet printer of this aspect, it is possible to provide an inkjet printer that can effectively attach the ink mist to the platen side, reduce defects due to the ink mist, and reduce deterioration of print image quality.

(2) In the inkjet printer according to the above-described embodiment, the electrode of the platen member has a shape having at least one long-side electrode and a plurality of short-side electrodes, and the interval between the plurality of short-side electrodes is approximately a standard paper size. May be adjusted to each width.
According to the inkjet printer of this aspect, it is possible to effectively reduce the generation of ink mist during borderless printing of standard paper, reduce the floating of paper dust from the paper, and reduce the deterioration of print image quality. Can be provided.

(3) In the inkjet printer according to the above aspect, the electrode of the platen member has an absorber made of an insulating material on a side facing the ink ejection surface side of the ink ejection head, and the absorber is the electrode. You may arrange | position in the state which covers the whole.
According to the inkjet printer of this aspect, it is possible to provide an inkjet printer capable of avoiding a discharge due to the application of a high electric field between the nozzle plate and the electrode of the platen member, and avoiding a malfunction of the device due to the occurrence of the discharge.

(4) According to another aspect of the present disclosure, there is provided an inkjet printer that forms an image on a print target by ejecting ink from a nozzle plate having a nozzle opening. According to the ink jet printer of this aspect, the metal casing has a cap member for flushing the nozzle opening with ink droplets, and the electrode of the cap member constitutes the ink jet printer and is set to the GND potential. And a mechanism for generating a potential difference, and the electrode of the cap member has an opening having an area larger than the area of the ink ejection surface of the nozzle plate.
According to the inkjet printer of this aspect, it is possible to provide the inkjet printer that can effectively attach the ink mist to the cap side, improve the effect of flushing, and reduce the deterioration of the print image quality.

(5) In the inkjet printer according to the above aspect, the electrode of the cap member has an absorbing material made of an insulating material on a side facing the ink ejection surface side of the ink ejection head including the nozzle plate, and the absorbing material. May be arranged so as to cover the entire electrode.
According to the inkjet printer of this aspect, it is possible to provide an inkjet printer capable of avoiding a discharge due to the application of a high electric field between the electrodes of the nozzle plate and the cap member, and avoiding a malfunction of the device due to the occurrence of discharge.

  The present disclosure can be implemented in various forms other than the inkjet printer. For example, it can be implemented in the form of an inkjet printer manufacturing method, an inkjet printer control method, a computer program that implements the control method, a non-transitory recording medium that records the computer program, or the like.

DESCRIPTION OF SYMBOLS 1 ... Head unit, 2 ... Liquid supply means, 2a ... Supply pipe, 3 ... Carriage, 4 ... Device body, 5 ... Carriage shaft, 6 ... Drive motor, 7 ... Timing belt, 9 ... Suction device, 9b ... Suction pipe, 9c ... Pump, 13a ... Paper ejection roller, 13b ... Paper ejection roller, 14a ... Paper feeding roller, 14b ... Paper feeding roller, 100 ... Platen member, 110 ... Absorption member, 120 ... Electrode, 121 ... Long side electrode, 122 ... Long-side electrode, 123 ... Terminal part, 125 ... Short-side electrode, 126 ... Short-side electrode, 130 ... Main body, 131 ... Recess, 132 ... Groove, 150 ... Paper, 151 ... Edge, 180 ... Ink jet type ejection head, 181 ... Nozzle plate, 182 ... Nozzle opening, 183 ... Cover head, 200 ... Platen member, 210 ... Absorption member, 220 ... Electrode, 221 ... Long side electrode, 223 ... End 225 ... Short side electrode, 226 ... Short side electrode, 230 ... Main body, 231 ... Recessed portion, 232 ... Groove, 300 ... Cap member, 310 ... Absorbing member, 320 ... Electrode, 323 ... Terminal portion, 325 ... Opening portion, 330 ... Main body, 331 ... Recessed portion, 332 ... Groove, 335 ... Opening portion, 340 ... Negative pressure, 400 ... Control device

Claims (5)

An inkjet printer that ejects ink from a nozzle plate having nozzle openings to form an image on a print target,
On the back side of the printing target during the image printing process, ink is ejected to a region facing the ink ejection head including the nozzle plate and to the outside of the printing target to form ink droplets. A mechanism for generating an electric field is provided between the electrode of the platen member arranged in the covered region and the metal casing that is included in the inkjet printer and is set to the GND potential.
The electrode of the platen member, when opposed to the ink ejection surface of the ink ejection head including the nozzle plate, is larger than the area of the ink ejection surface of the ink ejection head including the nozzle plate,
The area of the platen member on the opposite surface side of the electrode is small,
Inkjet printer characterized by. The electrode of the platen member is
A shape having at least one long side electrode and a plurality of short side electrodes,
The interval between the plurality of short side electrodes is adjusted to each width of a substantially standard paper size,
The inkjet printer according to claim 1. The electrode of the platen member has an absorbing material made of an insulating material on a side facing the ink ejection surface side of the ink ejection head,
The absorber is arranged so as to cover the entire electrode,
The inkjet printer according to claim 1 or 2. An inkjet printer that ejects ink from a nozzle plate having nozzle openings to form an image on a print target,
It has a cap member for flushing the nozzle opening with ink droplets,
The electrode of the cap member has a mechanism for generating a potential difference between the electrode and the metal casing, which is included in the inkjet printer and is set to the GND potential,
The electrode of the cap member has an opening having an area larger than the area of the ink ejection surface of the nozzle plate,
inkjet printer. The electrode of the cap member has an absorber made of an insulating material on a side facing the ink ejection surface side of the ink ejection head including the nozzle plate,
The absorber is arranged so as to cover the entire electrode,
The inkjet printer according to claim 4.

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