JP2005059326A - Head cleaning device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that nonejection and curved ejection are not eliminated because waste matter cannot be perfectly removed by a cleaning device using a brush and a cleaning fluid which does not contain a surface active agent. <P>SOLUTION: After the cleaning fluid 60 containing the surface active agent is jetted onto a nozzle surface Na of a head 14 from a cleaning-fluid jet spray 42 in a state wherein the nozzle surface Na of the head 14 is covered with a cap 41, the nozzle surface Na is made clean by using the brush 55. Thus, an agglomerate is dispersed by the action of the surface active agent contained in the cleaning fluid 60; releasability of the agglomerate and the nozzle surface Na is enhanced; and the agglomerate is removed by means of the brush 55. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a head cleaning device and an image forming apparatus, and more particularly to a head cleaning device that cleans a nozzle surface of a droplet discharge head that discharges droplets and an image forming apparatus including the device.

  Inkjet recording devices used as various image forming devices such as printers, facsimiles, copying machines, plotters, etc., form (record) images by mounting a droplet discharge head that discharges liquid recording liquid (ink) from fine nozzles. )

  Since the ink used in this ink jet recording apparatus contains volatile liquid such as water, the volatile liquid evaporates and thickens or aggregates when it is not used for a long period of time. May occur. If clogging occurs, ink cannot be ejected, resulting in an image defect.

  Therefore, in general, in order to recover the clogging of the nozzle, suction is performed in a state where the nozzle surface is sealed with a cap or the like to discharge the ink.

  However, when an ink containing a pigment that easily aggregates (so-called pigment ink) is used, when the ink dries, it becomes a highly aggregated state that cannot be recovered by ink suction. In addition, when a thermal head is used, continuous printing promotes evaporation of volatile components due to heating of the head, resulting in faster drying. Again, a highly agglomerated state that cannot be recovered by ink suction. turn into.

Therefore, in order to solve this problem, for example, a recording head cleaning device including a roller for removing unnecessary materials from the recording head and a means for rotating the roller has been proposed.
JP-A-10-217491

Further, there has been proposed a liquid ejection apparatus including a wiping means for wiping the liquid ejection portion on the outer peripheral surface of a cylindrical rotating wiping member having liquid impregnation property and a cleaning liquid supply means for supplying a cleaning liquid to the wiping member.
JP-A-11-334095

Further, there has been proposed a cleaning device for an ink discharge unit that has a roller that contacts and rotates with the ink discharge unit, an elastic body is disposed on the roller surface, and a cleaning liquid supply unit that supplies a cleaning liquid to the elastic body.
JP 2002-172895 A

Furthermore, the cleaner is sprayed from the cleaner spray that faces the ink nozzles of the ink jet printer head, and the ink in the ink nozzles flows into the ink reservoir, and the ink nozzle opening is cleaned by the rotating brush. Nozzle cleaning devices have been proposed.
Japanese Utility Model Publication No. 7-16433

  In the apparatus of Patent Document 1, there is a problem that even if a part of the thickened material can be scraped off, a portion that cannot be removed remains when the inside of the nozzle or the nozzle is uneven.

  In the devices of Patent Documents 2 and 3, the waste liquid can be removed by supplying the cleaning liquid to the roller and wiping the nozzle surface. There is a problem that will remain.

  Even in the apparatus of Patent Document 4, dirt on the nozzle surface can be removed, but it is satisfactory in that highly agglomerated aggregates cannot be removed even with the use of ethanol as an example of a cleaner. It was confirmed that it was not a thing.

  The present invention has been made in view of the above problems, and a head cleaning device capable of effectively removing the liquid thickened or agglomerated in the nozzle surface or in the nozzle to eliminate clogging of the nozzle, and this head cleaning device. An object of the present invention is to provide an image forming apparatus that can perform clear image formation without image defects.

  A head cleaning device according to the present invention is a head cleaning device for cleaning by bringing a brush into contact with a nozzle surface of a droplet discharge head for discharging droplets from a nozzle, and a cleaning liquid containing a surfactant on the nozzle surface of the head The cleaning liquid supply means for supplying the liquid is provided.

  Here, the cleaning agent preferably contains at least one of an antifoaming agent, an antiseptic / antifungal agent, a rust preventing agent, and a moisturizing agent, and the moisturizing agent is preferably a water-soluble organic solvent.

  The cleaning liquid supply means preferably supplies the cleaning liquid directly to the nozzle surface. In this case, the cleaning liquid is directly supplied to the nozzle surface by spraying or a porous body impregnated with the cleaning liquid is brought into contact with the nozzle surface. It is preferable.

  Alternatively, it is preferable to supply the cleaning liquid to the nozzle surface after supplying the cleaning liquid to the brush. In this case, the cleaning liquid is supplied to the brush by spraying, and the porous body impregnated with the cleaning liquid is brought into contact with the brush. It is preferable that the brush is supplied by immersing a part of the brush in the cleaning liquid.

  Further, it is preferable that the supply of the cleaning liquid to the nozzle surface is performed in a cleaning liquid scattering prevention chamber in close contact with the nozzle surface. In this case, it is preferable that the cleaning liquid scattering prevention chamber is formed by a cap.

  An image forming apparatus according to the present invention includes a liquid droplet ejection head for ejecting liquid droplets from a nozzle to form an image on a recording medium, a liquid cartridge that stores liquid to be supplied to the liquid droplet ejection head, And a head cleaning device according to the present invention for cleaning the nozzle surface of the droplet discharge head.

  Here, it is preferable that the droplet discharge head discharges droplets by utilizing film boiling generated in the liquid by the thermal energy generated by the electrothermal conversion means. The liquid is preferably a recording liquid containing a color material, and the color material of the recording liquid is preferably a pigment.

  In addition, it is preferable to include a liquid droplet discharge head that discharges a recording liquid containing a coloring material and a processing liquid that does not contain a coloring material and generates aggregates or insolubles by contacting the recording liquid. .

  According to the head cleaning device and the image forming apparatus according to the present invention, the cleaning liquid containing the surfactant is supplied to the nozzle surface of the head, and the nozzle surface is cleaned by bringing a brush into contact therewith. Aggregates can be dispersed, the peelability between the aggregates and the nozzle surface can be improved, and unnecessary materials in the recesses on the nozzle surface can also be removed by brushing. Thereby, occurrence of image defects can be prevented.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic perspective view of a mechanism portion of an ink jet recording apparatus as an image forming apparatus according to the present invention, and FIG. 2 is a side view of the mechanism portion.

  The ink jet recording apparatus includes a carriage that is movable in the main scanning direction inside the recording apparatus main body 1, a recording head that includes an ink jet head mounted on the carriage, an ink cartridge that supplies ink to the recording head, and the like. 2 and the like, the paper 3 fed from the paper feed cassette 4 or the manual feed tray 5 is taken in, a required image is recorded by the printing mechanism unit 2, and then discharged to the paper discharge tray 6 mounted on the rear side. Make paper.

  The printing mechanism unit 2 holds the carriage 13 slidably in the main scanning direction (vertical direction in FIG. 2) with a main guide rod 11 and a sub guide rod 12 which are guide members horizontally mounted on left and right side plates (not shown). doing.

  As shown in FIG. 3, the carriage 13 receives ink droplets, which are recording liquid droplets containing color materials of yellow (Y), cyan (C), magenta (M), and black (Bk). Four droplet discharge heads 14y, 14m, 14c, and 14k (collectively referred to as “recording head 14a”) having a nozzle row composed of a plurality of nozzles N to be discharged, ink containing no coloring material, and ink A processing liquid head 14 s composed of a droplet discharge head that discharges a processing liquid that generates aggregates or insolubles by contact is mounted, and the recording head 14 a and the processing liquid head are disposed above the carriage 13. Each liquid cartridge 15 for supplying each color ink or processing liquid to 14s is replaceably mounted.

  The ink cartridge containing the ink to be supplied to the recording head 14a in the liquid cartridge 15 is filled with ink in the upper atmosphere port which communicates with the atmosphere, the lower supply port which supplies ink to the head, and the inside. It has a porous body, and the ink supplied to the head is maintained at a slight negative pressure by the capillary force of the porous body.

  Here, the carriage 13 is slidably fitted to the main guide rod 11 on the rear side (downstream side in the paper conveyance direction), and is slidably mounted on the secondary guide rod 12 on the front side (upstream side in the paper conveyance direction). doing. In order to move and scan the carriage 13 in the main scanning direction, a timing belt 20 is stretched between a driving pulley 18 and a driven pulley 19 that are rotationally driven by a main scanning motor 17. The carriage 13 is reciprocally driven by forward and reverse rotation of the main scanning motor 17.

  Further, although the recording head 14a for ejecting ink droplets uses a head for each color, it may be a single head having nozzles for ejecting ink droplets for each color. The droplet discharge head constituting the recording head 14 is preferably a thermal head that discharges droplets by utilizing film boiling generated in the liquid by the thermal energy generated by the electrothermal conversion means. A head configuration using means may be used.

  On the other hand, in order to convey the paper 3 set in the paper feed cassette 4 to the lower side of the recording head 14a and the processing liquid head 14s, a paper feed roller 21 and a friction pad 22 for separating and feeding the paper 3 from the paper feed cassette 4; The guide member 23 for guiding the paper 3, the transport roller 24 for reversing and transporting the fed paper 3, the transport roller 25 pressed against the peripheral surface of the transport roller 24, and the transport roller 24 from the transport roller 24 A leading end roller 26 for defining the feed angle is provided. The transport roller 24 is rotationally driven by a sub-scanning motor 27 through a gear train.

  A printing receiving member 29, which is a paper guide member for guiding the paper 3 fed from the transport roller 24 corresponding to the movement range of the carriage 13 in the main scanning direction, below the recording head 14a and the processing liquid head 14s. Provided. A conveyance roller 31 and a spur 32 that are rotationally driven to send the paper 3 in the paper discharge direction are provided on the downstream side of the printing receiving member 29 in the paper conveyance direction, and the paper 3 is further delivered to the paper discharge tray 6. A roller 33 and a spur 34, and guide members 35 and 36 that form a paper discharge path are disposed.

  At the time of recording, the recording head 14a and the treatment liquid head 14s are driven according to the image signal while moving the carriage 13, thereby ejecting ink onto the stopped sheet 3 to record one line, After the predetermined amount is conveyed, the next line is recorded. Upon receiving a recording end signal or a signal that the trailing edge of the sheet 3 has reached the recording area, the recording operation is terminated and the sheet 3 is discharged.

  Here, the recording on the paper 3 is performed by ejecting the processing liquid from the processing liquid head 14 s according to the image to be recorded on the paper 3, and then ejecting ink droplets from the recording head 14 a according to the image to be recorded on the paper 3. This is done by discharging. Note that a configuration without a droplet discharge head for discharging the treatment liquid may be employed.

  Further, a recovery device 37 including a head cleaning device according to the present invention for recovering defective ejection of the recording head 14a and the treatment liquid head 14s is disposed at a position outside the recording area on the right end side in the movement direction of the carriage 13. ing. The recovery device 37 includes a cap unit, a suction unit, and a cleaning unit. During printing standby, the carriage 13 is moved to the recovery device 37 side, the recording head 14a and the treatment liquid head 14s are capped by the capping means, and the discharge port (nozzle hole) is kept in a wet state, thereby discharging by ink drying. Prevent defects. Further, by ejecting (purging) ink not related to recording during recording or the like, the ink viscosity of all the ejection ports is made constant and stable ejection performance is maintained.

  When a discharge failure occurs, the capping unit seals the discharge ports (nozzles) of the recording head 14a and the processing liquid head 14s, and sucks out bubbles and the like from the discharge port through the tube with the suction unit. Adhering ink, dust, etc. are removed by the cleaning means, and the ejection failure is recovered. Further, the sucked ink is discharged to a waste ink reservoir (not shown) installed at the lower part of the main body and absorbed and held by an ink absorber inside the waste ink reservoir.

Next, the cleaning liquid that can be used in the head cleaning device according to the present invention will be described.
The cleaning liquid contains a surfactant. The surfactant has an effect of fragmenting and dispersing the aggregate due to the surface active effect between the cleaning liquid and the aggregate. Further, since it has a function of lowering the surface tension of the cleaning liquid, the cleaning liquid easily enters between the aggregate and the nozzle surface, and there is an effect of easily separating the aggregate from the nozzle surface.

  As the surfactant, any compound having a hydrophilic part and a hydrophobic part in the same molecule can be preferably used.

  As specific examples, those represented by the following formulas (I) to (IV) are preferable. That is, a polyoxyethylene alkylphenyl ether surfactant of the following formula (I), an acetylene glycol surfactant of the formula (II), a polyoxyethylene alkyl ether surfactant of the following formula (III) and the formula (IV ) Polyoxyethylene polyoxypropylene alkyl ether surfactants.

（Ｒは分岐していても良い炭素数６〜１４の炭化水素鎖、ｋ：５〜２０）

(R is an optionally branched hydrocarbon chain having 6 to 14 carbon atoms, k: 5 to 20)

（ｍ、ｎ≦２０，０＜ｍ＋ｎ≦４０）

(M, n ≦ 20, 0 <m + n ≦ 40)

（Ｒは分岐してもよい炭素数６〜１４の炭化水素鎖、ｎは５〜２０）

(R is a C6-C14 hydrocarbon chain which may be branched, n is 5-20)

（Ｒは炭素数６〜１４の炭化水素鎖、ｍ、ｎは２０以下の数）

(R is a hydrocarbon chain having 6 to 14 carbon atoms, m and n are numbers of 20 or less)

  Other than the compounds of the above formulas (I) to (IV), for example, diethylene glycol monophenyl ether, ethylene glycol monophenyl ether, ethylene glycol monoallyl ether, diethylene glycol monophenyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, tetraethylene glycol chlorophenyl Use alkyl and aryl ethers of polyhydric alcohols such as ethers, nonionic surfactants such as polyoxyethylene polyoxypropylene block copolymers, fluorine-based surfactants, lower alcohols such as ethanol and 2-propanol However, diethylene glycol monobutyl ether is particularly preferable.

  As the antifoaming agent used in the present invention, any component having an antifoaming effect can be used. Among them, a silicon-based antifoaming agent is preferably used. Since foaming can be suppressed by adding an antifoaming agent, it is preferable to use it together with a surfactant. If no defoaming agent is added, once foaming occurs, foaming does not disappear easily, and bubbles of cleaning agent remain around the brush and around the head. In some cases, this foam interferes with printing and causes image defects. Will lead to.

  Thus, by adding an antifoaming agent to the cleaning liquid, it is possible to suppress foaming of the cleaning liquid, it is possible to prevent foaming around the head, and it is possible to prevent foam from inhibiting the ejection of the recording liquid, Generation of image defects can be prevented.

  In general, silicone type antifoaming agents include oil type, compound type, self-emulsifying type, emulsion type, etc., but considering the use in water system, it is reliable to use self-emulsifying type or emulsion type. Desirable in securing. Further, modified silicon-based antifoaming agents such as amino-modified, carbinol-modified, methacryl-modified, polyether-modified, alkyl-modified, higher fatty acid ester-modified, alkylene oxide-modified, etc. may be used.

  Commercially available silicone-based antifoaming agents include silicone antifoaming agents from Shin-Etsu Chemical Co., Ltd. (KS508, KS531, KM72, KM85, etc.) and silicone antifoaming agents from Toray Dow Corning Co., Ltd. (Q2-3183A, SH5510, etc.), Nippon Unicar Co., Ltd. silicone antifoaming agents (SAG30, etc.), Asahi Denka Kogyo Co., Ltd. antifoaming agents (Adecanol series), and the like.

  The amount of these antifoaming agents added to the ink may be the minimum amount that is effective, but generally it is preferably in the range of 0.001% to 3% by weight, more preferably 0.005% to 0.5%. It is the range of mass%.

  Examples of antiseptic / antifungal agents used in the present invention include sodium dehydroacetate, sodium sorbate, sodium 2-pyridinethiol-1-oxide, isothiazoline-based compounds, sodium benzoate, and sodium pentachlorophenol. By adding an antiseptic / antifungal agent, it is possible to suppress the occurrence of corrosion and soot even when the cleaning liquid is stored for a long period of time.

  In this way, by adding antiseptic and antifungal agents to the cleaning liquid, it is possible to prevent the occurrence of corrosion and wrinkles even when the cleaning liquid is stored for a long period of time. Can be prevented.

  Examples of the rust preventive used in the present invention include acidic sulfite, sodium thiosulfate, ammonium thiodiglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, dicyclohexylammonium nitrite and the like. By adding a rust preventive agent, it is possible to prevent rusting of a metal member such as around the head.

  In this way, by including a rust inhibitor in the cleaning solution, corrosion of metal parts such as the head can be prevented, the head can be operated normally over a long period of time, and image defects can be prevented. Can do.

  Examples of the humectant used in the present invention include the following specific examples. By adding a moisturizing agent, it is possible to suppress the drying of the recording liquid leading to nozzle clogging and to prevent the occurrence of image defects due to aggregates.

  Ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,5-pentanediol, 1,5-hexanediol, glycerol, 1,2,6-hexanetriol, 1,2,4-butanetriol, 1 Polyhydric alcohols such as 1,2,3-butanetriol and petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol mono Polyhydric alcohol alkyl ethers such as ethyl ether, ethylene glycol monophenyl ether, ether Including polyhydric alcohol aryl ethers such as lenglycol monobenzyl ether, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethylimidazolidinone, ε-caprolactam, etc. Nitrogen heterocyclic compounds, amides such as formamide, N-methylformamide, N, N-dimethylformamide, amines such as monoethanolamine, diethanolamine, triethanolamine, monoethylamine, diethylamine, triethylamine, dimethyl sulfoxide, sulfolane, thio Sulfur-containing compounds such as diethanol, propylene carbonate, ethylene carbonate, and γ-butyrolactone. These solvents are used alone or in combination with water.

  Of these, diethylene glycol, thiodiethanol, polyethylene glycol 200 to 600, triethylene glycol, glycerol, 1,2,6-hexanetriol, 1,2,4-butanetriol, petriol, 1,5 are particularly preferable. -Pentanediol, N-methyl-2-pyrrolidone, N-hydroxyethylpyrrolidone, 2-pyrrolidone, 1,3-dimethylimidazolidinone. By using these compounds, the high solubility of the present compound and the jetting properties due to water evaporation An excellent effect for prevention of defects is obtained. In the present invention, pyrrolidone derivatives such as N-hydroxyethyl-2-pyrrolidone are particularly preferable for obtaining dispersion stability of compound (I).

Next, a first embodiment of the head cleaning device according to the present invention will be described with reference to FIGS. 4 is a schematic configuration diagram of the cleaning device, and FIG. 5 is an explanatory diagram for explaining its operation.
With respect to the nozzle surface Na that also serves as a cleaning liquid splash prevention chamber for capping the nozzle surface Na (see FIG. 3) formed by the nozzle plate 14A of the recording head 14a or the processing liquid head 14s (this is referred to as “head 14”). The cap 41 disposed so as to be able to advance and retreat in the facing direction, the cleaning liquid spray 42 for spraying the cleaning liquid in the cap 41, the cleaning liquid cartridge 43 containing the cleaning liquid containing the surfactant, and the cleaning liquid in the cleaning liquid cartridge 43 as the cleaning liquid A cleaning liquid injection pump 44 and cleaning liquid supply tubes 45 and 46 for supplying and spraying to the spray 42 are provided.

  Further, a waste liquid suction pump 51 that sucks waste liquid from the cap 41, a waste liquid tank 52 that stores the waste liquid, a suction tube 53, and a waste liquid tube 54 are provided.

  Further, a rotatable brush 55 for cleaning the nozzle surface Na of the head 14 and a brush moving means 56 for moving the brush 55 forward and backward in a direction parallel to the nozzle surface Na while being in contact with the nozzle surface Na are provided. .

  Since it comprised in this way, when performing the recovery | restoration operation | movement of the nozzle N of the head 14, the nozzle surface Na of the head 14 is first capped by the cap 41 which also serves as the cleaning liquid scattering prevention chamber. Thereafter, the inside of the cap 41 is made negative pressure by the waste liquid suction pump 51, whereby the ink or the processing liquid is sucked from the nozzle N of the head 14 and stored in the waste liquid tank 52.

  Next, the cleaning liquid stored in the cleaning liquid cartridge 43 is transferred to the cleaning liquid injection spray 42 by the cleaning liquid injection pump 44, and the cleaning liquid is discharged from the cleaning liquid injection spray 42 with the cap 41 in close contact with the nozzle surface Na as shown in FIG. Let spray. As a result, the cleaning liquid adheres to the nozzle surface Na and the nozzle N.

  Thereafter, the brush 55 is moved by the brush moving means 56 while rotating, and the nozzle surface Na is brushed.

  By this series of operations, the ink thickened material and the ink aggregate on the nozzle surface are removed.

  At this time, the agglomerate can be dispersed by the action of the surfactant contained in the cleaning liquid, the peelability between the agglomerate and the nozzle surface can be improved, and unnecessary parts in the recesses on the nozzle surface are also removed by brushing. can do.

  In addition, by spraying the cleaning agent directly onto the nozzle surface, it is possible to apply a cleaning liquid during brushing, and it is possible to prevent the occurrence of image defects by removing aggregates and to cool the head. , The formation of aggregates can be suppressed.

Next, a second embodiment of the head cleaning apparatus according to the present invention will be described with reference to FIG.
Here, the nozzle surface Na of the head 14 is capped, and a cleaning liquid scattering prevention chamber member 58 that forms a cleaning liquid scattering prevention chamber 58 a that houses the brush 55 is provided.

  Then, the cleaning liquid spray spray 42 sprays the cleaning liquid 60 in a state where the cleaning liquid scattering prevention chamber member 58 is in close contact with the nozzle surface Na of the head 14, and the cleaning liquid adheres to the nozzle surface Na of the head 14. Move left and right with.

  In this process, the cleaning liquid is sprayed onto the nozzle surface Na to cool the head 14, and this also has the effect of suppressing ink drying due to head heating when a thermal head is used.

  In this way, by supplying the cleaning liquid in the cleaning liquid scattering prevention chamber or the cap, it is possible to prevent the inside of the image forming apparatus from being contaminated with the cleaning liquid without attaching the cleaning liquid to unnecessary portions.

Next, a third embodiment of the head cleaning device according to the present invention will be described with reference to FIG.
Here, a cap 61 that caps the nozzle surface Na of the head 14 and is disposed so as to be able to advance and retreat in a direction facing the nozzle surface Na, and a waste liquid suction pump that sucks waste liquid from the cap 61 as in the above embodiment. 51, a waste liquid tank 52 for storing waste liquid, a suction tube 53, and a waste liquid tube 54.

  Also, a cleaning liquid spraying spray 62 for spraying the cleaning liquid onto the porous body 67, a cleaning liquid cartridge 63 containing the cleaning liquid, a cleaning liquid, which is disposed on the side opposite to the brush 55 at the recovery operation position of the head 14, A cleaning liquid injection pump 64 for supplying the cleaning liquid of the cartridge 63 to the cleaning liquid injection spray 62 and injecting the cleaning liquid and cleaning liquid supply tubes 65 and 66 are provided.

  A porous body 67 that absorbs and holds the cleaning liquid sprayed from the cleaning liquid spray spray 62, and a porous body that advances and retreats in parallel with the nozzle surface Na while contacting the porous body 67 with the nozzle surface Na. Moving means 68.

  Further, as in the first embodiment, a rotatable brush 55 that cleans the nozzle surface Na of the head 14 and a brush that advances and retreats the brush 55 in a direction parallel to the nozzle surface Na while being in contact with the nozzle surface Na. Moving means 56.

  With this configuration, when the recovery operation of the nozzle N of the head 14 is performed, the nozzle surface Na of the head 14 is first capped by the cap 61. After that, the waste liquid suction pump 51 makes the inside of the cap 61 have a negative pressure, whereby the ink or the processing liquid is sucked from the nozzle N of the head 14 and stored in the waste liquid tank 52.

  Next, the cleaning liquid stored in the cleaning liquid cartridge 63 is transferred to the cleaning liquid jet spray 62 by the cleaning liquid jet pump 64. With this momentum, the cleaning liquid is sprayed from the cleaning liquid spray 62 and the cleaning liquid adheres to the porous body 67. The porous body 67 with the cleaning liquid attached is moved to the head 14 side by the porous body moving means 68, and the cleaning liquid is attached to the nozzle surface Na.

  Thereafter, the brush 55 is moved by the brush moving means 56 while rotating, and the nozzle surface Na is brushed.

  By this series of operations, the ink thickened material and the ink aggregate on the nozzle surface are removed. That is, the function of the surfactant contained in the cleaning liquid can disperse the aggregate and improve the peelability between the aggregate and the nozzle surface, so that the ink thickener on the nozzle surface by brushing, and Ink agglomerates are removed.

  In this way, by impregnating the porous body with the cleaning liquid and bringing the porous body into contact with the nozzle surface, the cleaning liquid can be reliably applied to the nozzle surface without attaching the cleaning liquid to unnecessary portions.

Next, a fourth embodiment of the head cleaning device according to the present invention will be described with reference to FIG.
Here, a cap 61 that caps the nozzle surface Na of the head 14 and is disposed so as to be able to advance and retreat in a direction facing the nozzle surface Na, and a waste liquid suction pump that sucks waste liquid from the cap 61 as in the above embodiment. 51, a waste liquid tank 52 for storing waste liquid, a suction tube 53, and a waste liquid tube 54.

  Further, at the recovery operation position of the head 14, the cleaning liquid spray 62 is disposed on the side of the head 14 in the same manner as the brush 55, sprays the cleaning liquid onto the brush 55, the cleaning liquid cartridge 63 containing the cleaning liquid, and the cleaning liquid cartridge 63. The cleaning liquid jet pump 64 and the cleaning liquid supply tubes 65 and 66 are provided for supplying the cleaning liquid to the cleaning liquid jet spray 62 and jetting it.

  Further, as in the first embodiment, a rotatable brush 55 that cleans the nozzle surface Na of the head 14 and a brush that advances and retreats the brush 55 in a direction parallel to the nozzle surface Na while being in contact with the nozzle surface Na. Moving means 56.

  With this configuration, when the recovery operation of the nozzle N of the head 14 is performed, the nozzle surface Na of the head 14 is first capped by the cap 61. After that, the waste liquid suction pump 51 makes the inside of the cap 61 have a negative pressure, whereby the ink or the processing liquid is sucked from the nozzle N of the head 14 and stored in the waste liquid tank 52.

  Next, the cleaning liquid stored in the cleaning liquid cartridge 63 is transferred to the cleaning liquid jet spray 62 by the cleaning liquid jet pump 64. With this momentum, the cleaning liquid is sprayed from the cleaning liquid spray 62 and the cleaning liquid adheres to the brush 55.

  Therefore, the brush surface 55 is moved by the brush moving means 56 while rotating the brush 55 to which the cleaning liquid is adhered, and the nozzle surface Na is brushed.

  By this series of operations, the ink thickened material and the ink aggregate on the nozzle surface are removed. That is, at this time, the aggregates can be dispersed by the action of the surfactant contained in the cleaning liquid, the peelability between the aggregates and the nozzle surface can be improved, and the ink thickener on the nozzle surface by brushing. , And ink aggregates are removed.

  In this way, by supplying the cleaning liquid to the brush surface after being supplied to the brush, the cleaning liquid can be reliably applied to the nozzle surface without attaching the cleaning liquid to unnecessary portions. Then, an appropriate amount of cleaning liquid can be applied to the brush by spraying the cleaning liquid on the brush.

  In addition, the cleaning liquid can be impregnated into contact with the porous body, and even in this case, an appropriate amount of the cleaning liquid can be applied to the brush.

Next, a fifth embodiment of the head cleaning apparatus according to the present invention will be described with reference to FIG.
Here, a cap 61 that caps the nozzle surface Na of the head 14 and is disposed so as to be able to advance and retreat in a direction facing the nozzle surface Na, and a waste liquid suction pump that sucks waste liquid from the cap 61 as in the above embodiment. 51, a waste liquid tank 52 for storing waste liquid, a suction tube 53, and a waste liquid tube 54.

  Further, a cleaning liquid tank 72 disposed at a position where the required range of the tip of the brush 55 contacts the cleaning liquid 60, a cleaning liquid cartridge 73 containing the cleaning liquid, and a cleaning liquid for transferring the cleaning liquid from the cleaning liquid cartridge 73 to the cleaning liquid tank 72. An injection pump 74 and cleaning liquid supply tubes 75 and 76 are provided.

  Further, as in the first embodiment, a rotatable brush 55 that cleans the nozzle surface Na of the head 14 and a brush that advances and retreats the brush 55 in a direction parallel to the nozzle surface Na while being in contact with the nozzle surface Na. Moving means 56.

  With this configuration, when the recovery operation of the nozzle N of the head 14 is performed, the nozzle surface Na of the head 14 is first capped by the cap 61. After that, the waste liquid suction pump 51 makes the inside of the cap 61 have a negative pressure, whereby the ink or the processing liquid is sucked from the nozzle N of the head 14 and stored in the waste liquid tank 52.

  On the other hand, the cleaning liquid stored in the cleaning liquid cartridge 73 is transferred to the cleaning liquid tank 72 by the cleaning liquid injection pump 74, and the liquid level of the cleaning liquid 60 in the cleaning liquid tank 72 is such that the required range of the tip of the brush 55 is immersed in the cleaning liquid 60. Is maintained.

  Therefore, after the cleaning liquid 60 in the cleaning liquid tank 72 is attached to the tip while rotating the brush 55, the brush 55 is moved by the brush moving means 56 to brush the nozzle surface Na.

  By this series of operations, the ink thickened material and the ink aggregate on the nozzle surface are removed. That is, at this time, the aggregates can be dispersed by the action of the surfactant contained in the cleaning liquid, the peelability between the aggregates and the nozzle surface can be improved, and the ink thickener on the nozzle surface by brushing. , And ink aggregates are removed.

  Thus, the cleaning liquid can be applied to the entire brush by immersing the brush in the liquid surface of the cleaning liquid.

  The timing of supplying the cleaning liquid is not limited to the above example, and the cleaning liquid may be supplied before brushing by the brush, may be supplied during the brushing, or supplied after the brushing. May be.

  A cleaning liquid absorber can be provided around the head cleaning device. This absorber is installed for the purpose of absorbing the cleaning liquid scattered by cleaning and preventing the inside of the image forming apparatus from being contaminated by the cleaning liquid. Any absorber that absorbs the cleaning liquid can be used. Examples thereof include synthetic fibers such as polyester, natural fibers such as cotton and paper, and sponge-like porous bodies such as urethane.

  Furthermore, the brush that can be used in the present invention can be suitably used as long as it has an uneven shape on the outer periphery. That is, a thickened material or an aggregate can be scraped off by the presence of protrusions or depressions.

  For example, as shown in FIG. 10, a plurality of fibers 55 a is a brush 55 </ b> A projecting radially outward on the circumferential surface of the roller-like member 55 b, and as shown in FIG. 11, the plurality of fibers 55 a is a flat plate Brush 55B planted in member 55c and protruding outward in the same direction, as shown in FIG. 12, brush 55C with a fine protrusion 55e on the surface of roller member 55d, as shown in FIG. An example is a brush 55D having a fine protrusion 55g on the surface of the rolled porous body 55f.

  In this case, by using the fiber 55a having a diameter equal to or smaller than the nozzle diameter, it is possible to scrape thickeners and aggregates within the nozzle diameter.

  Further, as described above, the brush may be cylindrical or plate-shaped, and the shape is not particularly limited. In the case of a cylindrical shape, it may be rotated to rub the nozzle surface, or may be fixed and rubbed to the nozzle surface.

  As described above, by using the head cleaning device according to the present invention, it is possible to reliably remove unwanted materials from the nozzle, and by using the image forming apparatus equipped with this head cleaning device, it is stable over a long period of time. A clear image can be obtained.

  In the image forming apparatus according to the present invention, a head that ejects liquid droplets by thermal energy can be used. Since this head is excellent in that it can form nozzles at high density and can be manufactured at low cost, a clear image can be obtained with high resolution.

  However, when the discharge operation is continuously performed, the head that discharges by heat energy gradually accumulates heat and generates high heat. For this reason, the volatile components of the recording liquid and the processing liquid near the nozzles evaporate, resulting in thickening and aggregation, and non-ejection and ejection bending are likely to occur.

  For this reason, in the conventional image forming apparatus using a cleaning liquid and a brush that do not contain a surfactant, it is impossible to completely remove unnecessary materials, so that non-ejection and ejection bending cannot be solved. On the other hand, by providing the cleaning device according to the present invention, a cleaning liquid containing a surfactant having an effect of dispersing the thickened material and aggregates and an effect of peeling the thickened material and aggregates from the nozzle is provided. However, since it is rubbed with the brush, the thickened substance and aggregates in and near the nozzle can be effectively removed, thereby preventing non-ejection and ejection bending and forming a high-quality image.

  The image forming apparatus according to the present invention can use a recording liquid containing a pigment. By using a pigment as the color material, a printed matter having a high image density, no bleeding, and high water resistance can be obtained.

  However, when a recording liquid containing a pigment is used, when a volatile component in the recording liquid evaporates, the pigment is likely to be deposited inside or near the nozzle, and non-ejection or ejection bend is likely to occur.

  For this reason, in the conventional image forming apparatus using a cleaning liquid and a brush that do not contain a surfactant, it is impossible to completely remove unnecessary materials, so that non-ejection and ejection bending cannot be solved. On the other hand, by providing the cleaning device according to the present invention, a cleaning liquid containing a surfactant having an effect of dispersing the thickened material and aggregates and an effect of peeling the thickened material and aggregates from the nozzle is provided. However, since it is rubbed with a brush, it is possible to effectively remove thickeners and aggregates in and near the nozzle. Thereby, non-ejection and ejection bending can be suppressed, and a high-quality image can be formed.

  The image forming apparatus according to the present invention can use a processing liquid that generates aggregates or insolubles when contacted with a recording liquid. By using the treatment liquid, it is possible to obtain a printed matter having a higher image density, a wider color reproduction range, and higher water resistance than using the recording liquid alone.

  However, once the processing liquid comes into contact with the recording liquid, an aggregate is instantaneously generated. If this agglomerate is generated inside or in the vicinity of the nozzle, non-ejection or ejection bending is likely to occur.

  For this reason, in the conventional image forming apparatus using a cleaning liquid and a brush that do not contain a surfactant, it is impossible to completely remove unnecessary materials, so that non-ejection and ejection bending cannot be solved. On the other hand, by providing the cleaning device according to the present invention, a cleaning liquid containing a surfactant having an effect of dispersing the thickened material and aggregates and an effect of peeling the thickened material and aggregates from the nozzle is provided. However, since it is rubbed with a brush, it is possible to effectively remove thickeners and aggregates in and near the nozzle. Thereby, non-ejection and ejection bending can be suppressed, and a high-quality image can be formed.

  Here, an example of ink that is a liquid used in the image forming apparatus according to the present invention will be described, but it is needless to say that the present invention is not limited thereto.

  The ink contains a color material. The coloring material may be contained in a dissolved state or may be contained in a dispersed state. In this case, a dye is preferable as the coloring material used in a dissolved state. Examples of the color material used in a dispersed state include pigments and dyes having low solubility in solvents. By using a pigment, high light resistance and water resistance can be obtained.

  In these, it is preferable to contain a coloring material in the disperse | distributed state. In other words, when the coloring material is contained in a dispersed state, the pH change occurs at the moment of landing on the recording medium (paper) and the dispersion of the coloring material is destroyed and the coloring material aggregates, or the coloring material is a fiber of the recording medium. The phenomenon of being caught in the eyes and not flowing far away occurs. As a result of such a phenomenon, feathering and color bleeding can be suppressed, and a clear image can be obtained.

  On the contrary, if the coloring material is contained in a dissolved state, the dissolved coloring material does not easily precipitate even if a pH change occurs at the moment of landing on the recording medium, so that the coloring material does not aggregate. Further, in a state where the color material is dissolved, when the ink permeates the recording medium, the ink flows out far without being caught in the eyes of the fibers. As a result of such a phenomenon, feathering or color bleeding may occur, resulting in an unclear image.

  Examples of the dye that can be used include dyes that are classified into acid dyes, direct dyes, reactive dyes, and food dyes in the color index, and that have excellent water resistance and light resistance. These dyes may be used as a mixture of a plurality of types, or may be used as a mixture with other dyes such as pigments. These are added as long as the effect is not inhibited.

If these dyes are specifically mentioned, as acid dyes and food dyes,
C. I. Acid Yellow 17, 23, 42, 44, 79, 142,
C. I. Acid Red 1, 8, 13, 14, 18, 26, 27, 35, 37, 42, 52, 82, 87, 89, 92, 97, 106, 111, 114, 115, 134, 186, 249, 254, 289,
C. I. Acid Blue 9, 29, 45, 92, 249
C. I. Acid Black 1, 2
And so on.

As a direct dye,
C. I. Direct Yellow 1, 12, 24, 26, 33, 44, 50, 86, 120, 132, 142, 144,
C. I. Direct Red 1, 4, 9, 13, 17, 20, 28, 31, 39, 80, 81, 83, 89, 225, 227,
C. I. Direct Orange 26, 29, 62, 102,
C. I. Direct Blue 1, 2, 6, 15, 22, 25, 71, 76, 79, 86, 87, 90, 98, 163, 165, 199, 202,
C. I. Direct black 19, 22, 32, 38, 51, 56, 71, 74, 75, 77, 154, 168, 171
And so on.

As reactive dyes,
C. I. Reactive Black 3, 4, 7, 11, 12, 17,
C. I. Reactive Yellow 1, 5, 11, 13, 14, 20, 21, 22, 25, 40, 47, 51, 55, 65, 67,
C. I. Reactive Red 1, 14, 17, 25, 26, 32, 37, 44, 46, 55, 60, 66, 74, 79, 96, 97,
C. I. Reactive Blue 1, 2, 7, 14, 15, 23, 32, 35, 38, 41, 63, 80, 95
And so on.

  In particular, acid dyes and direct dyes can be preferably used.

  Specific examples of the pigment that can be used include the following. In this case, these pigments may be used by mixing a plurality of types, or may be used by mixing with other pigments such as dyes.

  Examples of organic pigments include azo, phthalocyanine, anthraquinone, dioxazine, indico, thioindico, perylene, isoindolenone, aniline black, azomethine, rhodamine B lake pigment, and carbon black.

  The pigment is preferably used in the form of particles having a particle diameter of 0.01 to 0.15 μm.

  Examples of inorganic pigments include iron oxide, titanium oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, bitumen, cadmium red, chrome yellow, and metal powder. Examples of organic pigments include azo, phthalocyanine, anthraquinone, quinacridone, dioxazine, indigo, thioindigo, perylene, isoindolenone, aniline black, azomethine, rhodamine B lake pigment, and carbon black. It is done.

  Further, the particle diameter of these pigments is preferably 0.01 to 0.15 μm. If it is 0.01 μm or less, the hiding power is lowered, the density is low, the light resistance is lowered, and the light resistance of the ink when mixed with the polymer dye system becomes equivalent to that of the conventional dye system. On the other hand, if the thickness is 0.15 μm or more, clogging of the head or clogging with a filter may occur, and it may not be possible to obtain ejection stability.

  Ink is used for the purpose of making the ink have the desired physical properties, preventing drying of the ink by preventing discharge failure, and improving the dissolution stability and dispersion stability of the coloring material. It is preferable to use a water-soluble organic solvent.

  That is, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,5-pentanediol, 1,5-hexanediol, glycerol, 1,2,6-hexanetriol, 1,2,4-butanetriol Polyhydric alcohols such as 1,2,3-butanetriol and petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene Polyhydric alcohol alkyl ethers such as glycol monoethyl ether, ethylene glycol monophenyl ether Ter, polyhydric alcohol aryl ethers such as ethylene glycol monobenzyl ether, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethylimidazolidinone, ε-capro Nitrogen-containing heterocyclic compounds such as lactam, amides such as formamide, N-methylformamide, N, N-dimethylformamide, amines such as monoethanolamine, diethanolamine, triethanolamine, monoethylamine, diethylamine, triethylamine, dimethyl sulfoxide Sulfur-containing compounds such as sulfolane and thiodiethanol, propylene carbonate, ethylene carbonate, and γ-butyrolactone. These solvents are used alone or in combination with water.

  Of these, diethylene glycol, thiodiethanol, polyethylene glycol 200 to 600, triethylene glycol, glycerol, 1,2,6-hexanetriol, 1,2,4-butanetriol, petriol, 1,5 are particularly preferable. -Pentanediol, N-methyl-2-pyrrolidone, N-hydroxyethylpyrrolidone, 2-pyrrolidone, 1,3-dimethylimidazolidinone. By using these, an excellent effect can be obtained for preventing poor jetting characteristics due to high solubility or high dispersibility of the coloring material and water evaporation.

The ink preferably contains a penetrant.
The penetrant is added for the purpose of improving the wettability between the ink and the recording medium and adjusting the penetrating speed. As the penetrant, those represented by the following formulas (I) to (IV) are preferable. That is, a polyoxyethylene alkylphenyl ether surfactant of the following formula (I), an acetylene glycol surfactant of the formula (II), a polyoxyethylene alkyl ether surfactant of the following formula (III) and the formula (IV The polyoxyethylene polyoxypropylene alkyl ether-based surfactant (1) can reduce the surface tension of the liquid, so that the wettability can be improved and the penetration rate can be increased.

（Ｒは分岐していても良い炭素数６〜１４の炭化水素鎖、ｋ：５〜２０）

(R is an optionally branched hydrocarbon chain having 6 to 14 carbon atoms, k: 5 to 20)

（ｍ、ｎ≦２０，０＜ｍ＋ｎ≦４０）

(M, n ≦ 20, 0 <m + n ≦ 40)

（Ｒは分岐してもよい炭素数６〜１４の炭化水素鎖、ｎは５〜２０）

(R is a C6-C14 hydrocarbon chain which may be branched, n is 5-20)

（Ｒは炭素数６〜１４の炭化水素鎖、ｍ、ｎは２０以下の数）

(R is a hydrocarbon chain having 6 to 14 carbon atoms, m and n are numbers of 20 or less)

  Other than the compounds of the above formulas (I) to (IV), for example, diethylene glycol monophenyl ether, ethylene glycol monophenyl ether, ethylene glycol monoallyl ether, diethylene glycol monophenyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, tetraethylene glycol chlorophenyl Use alkyl and aryl ethers of polyhydric alcohols such as ethers, nonionic surfactants such as polyoxyethylene polyoxypropylene block copolymers, fluorine-based surfactants, lower alcohols such as ethanol and 2-propanol However, diethylene glycol monobutyl ether is particularly preferable.

  Further, it is preferable to add a pH adjusting agent or a rust preventive agent to the ink for the purpose of preventing elution and corrosion of the member in contact with the ink. As the pH adjuster, any substance can be used as long as the pH can be adjusted to 6 or more without adversely affecting the prepared ink. For example, amines such as diethanolamine and triethanolamine, hydroxides of alkali metal elements such as lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonium hydroxide, quaternary ammonium hydroxide, quaternary phosphonium hydroxide Products, alkali metal carbonates such as lithium carbonate, sodium carbonate and potassium carbonate. Examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thiodiglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, and dicyclohexylammonium nitrite.

  Further, it is preferable to add an antiseptic / antifungal agent to the ink for the purpose of antiseptic / antifungal. As the antiseptic / antifungal agent, sodium dehydroacetate, sodium sorbate, 2-pyridinethiol-1-oxide sodium, isothiazoline-based compound, sodium benzoate, sodium pentachlorophenol and the like can be used.

  Furthermore, it is preferable to add an antifoaming agent to the ink in order to suppress unnecessary foaming. As the antifoaming agent, a silicon-based antifoaming agent is preferably used. In general, there are oil type, compound type, self-emulsification type, emulsion type, etc. for silicone antifoaming agent, but considering the use in water system, use of self-emulsification type or emulsion type ensures reliability. This is preferable. Further, modified silicon-based antifoaming agents such as amino-modified, carbinol-modified, methacryl-modified, polyether-modified, alkyl-modified, higher fatty acid ester-modified, alkylene oxide-modified, etc. may be used.

  Commercially available silicone-based antifoaming agents include silicone defoaming agents from Shin-Etsu Chemical Co., Ltd. (KS508, KS531, KM72, KM85, etc .: trade names), silicone from Toray Dow Corning Co., Ltd. Defoamers (Q2-3183A, SH5510, etc .: trade names), Silicone defoamers (SAG30, etc .: trade names) from Nihon Unicar Co., Ltd., Defoamers from Asahi Denka Kogyo Co., Ltd. ) And the like.

  The ink preferably has a viscosity at 20 ° C. of 4 mPa · sec or more. By setting it in the range of 4 mPa · sec, it is possible to prevent mist due to ink rebound, to ensure ejection stability, and to obtain a clearer image.

Next, specific examples will be described.
<Production example of cleaning liquid>
The following components were mixed to produce a cleaning liquid.
Surfactant (I) (R = C9H19, k = 12) 1.0 part humectant (glycerin) 10.0 parts silicone-based antifoaming agent (KM72, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 part antiseptic / antifungal agent (Produced by Avicia, PROXEL LV (s)) 0.5 parts Rust inhibitor (sodium thiosulfate) 0.5 parts Remaining amount of ion-exchanged water

<Example of production of recording liquid>
The following components were mixed to produce a recording liquid.
Carbon black (Cabot Jet, Cabot Jet 300) 10 parts moisturizer 1 (1,3-butanediol) 22.5 parts moisturizer 2 (glycerin) 7.5 parts moisturizer 3 (2-pyrrolidone) 2.0 parts interface Activator (I), R = C9H19, k = 12 1.0 part Antirust agent (sodium thiosulfate) 0.2 part Antiseptic / antifungal agent (Avicia, PROXEL LV (s)) 0.4 part ion exchange The remaining amount of water was further adjusted to pH 10.5 with an aqueous LiOH solution.

<Example of treatment liquid production>
The following components were mixed to produce a treatment liquid.
Cationic colloidal silica (manufactured by Nissan Chemical Co., Ltd .: Snowtex AK) 15.0 parts humectant 1 (2-pyrrolidone) 12.5 parts humectant 2 (diethylene glycol) 12.5 parts penetrant (octanediol) 0 parts cationic surfactant (manufactured by Sanyo Chemical Co., Ltd .: Cation G50) 2.0 parts antiseptic / antifungal agent (Avicia, PROXEL LV (s)) 0.2 parts ion-exchanged water remaining amount and pH 4 with acetic acid .3 to be used.

<Example>
(1) Example 1
When the cleaning device shown in FIG. 4 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid and the recording liquid were filled, and printing was performed, a clear image could be obtained. After printing, it was allowed to stand for 1 week at room temperature and normal humidity without capping. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no ink thickeners and aggregates on the nozzle surface, and the nozzles were not clogged.

(2) Example 2
When the cleaning device shown in FIG. 6 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid and the recording liquid were filled, and printing was performed, a clear image could be obtained. After printing, it was left for 1 week at room temperature and normal humidity without capping. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no ink thickeners and aggregates on the nozzle surface, and the nozzles were not clogged.

(3) Example 3
When the cleaning device shown in FIG. 7 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid and the recording liquid were filled and printing was performed, a clear image could be obtained. After printing, it was left for 1 week at room temperature and normal humidity without capping. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no ink thickeners and aggregates on the nozzle surface, and the nozzles were not clogged.

(4) Example 4
When the cleaning device shown in FIG. 8 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid and the recording liquid were filled, and printing was performed, a clear image could be obtained. After printing, it was left for 1 week at room temperature and normal humidity without capping. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no ink thickeners and aggregates on the nozzle surface, and the nozzles were not clogged.

(5) Example 5
When the cleaning device shown in FIG. 9 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid, the recording liquid, and the processing liquid were filled and printing was performed, a clear image could be obtained. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to have been produced by the reaction of the recording liquid and the processing liquid bounced off the recording surface, and the nozzle also It was confirmed that clogging occurred. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no aggregates on the nozzle surface and the nozzles were not clogged.

(6) Example 6
When the cleaning device shown in FIG. 7 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid, the recording liquid, and the processing liquid were filled and printing was performed, a clear image could be obtained. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to be generated due to the reaction between the recording liquid and the processing liquid bounced off the recording surface. It was confirmed that clogging occurred. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no aggregates on the nozzle surface and the nozzles were not clogged.

(7) Example 7
When the cleaning device shown in FIG. 8 was attached to the image forming apparatus shown in FIG. 1 and FIG. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to be generated due to the reaction between the recording liquid and the processing liquid bounced off the recording surface. It was confirmed that clogging occurred. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no aggregates on the nozzle surface and the nozzles were not clogged.

(8) Example 8
When the cleaning device shown in FIG. 9 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid, the recording liquid, and the processing liquid were filled and printing was performed, a clear image could be obtained. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to be generated due to the reaction between the recording liquid and the processing liquid bounced off the recording surface. It was confirmed that clogging occurred. After performing the cleaning operation, printing was performed again, and a clear image free from image defects could be obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that there were no aggregates on the nozzle surface and the nozzles were not clogged.

(9) Comparative Example 1
As shown in FIG. 14, the image forming apparatus shown in FIGS. 1 and 2 is attached with a cleaning device provided with a roller 101 instead of the brush 55 in FIG. 4, filled with cleaning liquid and recording liquid, and printed. A clear image could be obtained. After printing, it was left for 1 week at room temperature and normal humidity without capping. When printed again, an image with white streaks was obtained. After performing the cleaning operation, printing was performed again. As a result, white streaks did not disappear and an image with image defects was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(10) Comparative Example 2
As shown in FIG. 15, the image forming apparatus shown in FIGS. 1 and 2 is attached with a cleaning device provided with a blade 102 instead of the brush 55 in FIG. 4, filled with cleaning liquid and recording liquid, and printed. However, a clear image could be obtained. After printing, it was allowed to stand for 1 week at room temperature and normal humidity without capping. When printed again, an image with white streaks was obtained. After performing the cleaning operation, printing was performed again. As a result, white streaks did not disappear and an image with image defects was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(11) Comparative Example 3
As shown in FIG. 16, the image forming apparatus shown in FIGS. 1 and 2 is attached with a cleaning device that does not have the configuration related to the cleaning liquid in FIG. 14, filled with a recording liquid, and printed. I was able to get it. After printing, it was left for 1 week at room temperature and normal humidity without capping. When printed again, an image with white streaks was obtained. After performing the cleaning operation, printing was performed again. As a result, white streaks did not disappear and an image with image defects was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(12) Comparative Example 4
As shown in FIG. 17, the image forming apparatus shown in FIG. 1 and FIG. 2 is attached with a cleaning device that eliminates the configuration related to the cleaning liquid shown in FIG. 15, filled with the recording liquid, and printed. I was able to get it. After printing, it was left for 1 week at room temperature and normal humidity without capping. When printed again, an image with white streaks was obtained. After performing the cleaning operation, printing was performed again. As a result, white streaks did not disappear and an image with image defects was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(13) Comparative Example 5
As shown in FIG. 18, the image forming apparatus shown in FIGS. 1 and 2 uses the brush 55 of FIG. 4, but is attached with a cleaning device that eliminates the configuration related to the cleaning liquid, and is filled with a cleaning agent (ethanol) and a recording liquid. When printing was performed, a clear image could be obtained. After printing, it was left for 1 week at room temperature and normal humidity without capping. When printed again, an image with white streaks was obtained. After the cleaning operation, printing was performed again, and an image with white streaks was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(14) Comparative Example 6
When the cleaning device shown in FIG. 14 was attached to the image forming apparatus shown in FIGS. 1 and 2, the cleaning liquid, the recording liquid, and the processing liquid were filled and printing was performed, a clear image could be obtained. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to be generated due to the reaction between the recording liquid and the processing liquid bounced off the recording surface. It was confirmed that clogging occurred. After the cleaning operation, printing was performed again, and an image with white streaks was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(15) Comparative Example 7
When the cleaning device shown in FIG. 15 was attached to the image forming apparatus shown in FIG. 1 and FIG. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to have been produced by the reaction of the recording liquid and the processing liquid bounced off the recording surface, and the nozzle also It was confirmed that clogging occurred. After the cleaning operation, printing was performed again, and an image with white streaks was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(16) Comparative Example 8
When the cleaning device shown in FIG. 16 was attached to the image forming apparatus shown in FIGS. 1 and 2, the recording liquid and the processing liquid were filled, and printing was performed, a clear image could be obtained. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to be generated due to the reaction between the recording liquid and the processing liquid bounced off the recording surface. It was confirmed that clogging occurred. After the cleaning operation, printing was performed again, and an image with white streaks was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(17) Comparative Example 9
When the cleaning device shown in FIG. 17 was attached to the image forming apparatus shown in FIGS. 1 and 2, the recording liquid and the processing liquid were filled, and printing was performed, a clear image could be obtained. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to be generated due to the reaction between the recording liquid and the processing liquid bounced off the recording surface. It was confirmed that clogging occurred. After the cleaning operation, printing was performed again, and an image with white streaks was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

(18) Comparative Example 10
When the cleaning device shown in FIG. 18 was attached to the image forming apparatus shown in FIGS. 1 and 2, the recording liquid and the processing liquid were filled, and printing was performed, a clear image could be obtained. When 100 sheets were printed continuously, white streaks occurred. When the nozzle surface was observed with an optical microscope without performing the cleaning operation, the nozzle surface had agglomerates that were thought to be generated due to the reaction between the recording liquid and the processing liquid bounced off the recording surface. It was confirmed that clogging occurred. After the cleaning operation, printing was performed again, and an image with white streaks was obtained. When the nozzle surface was observed with an optical microscope, it was confirmed that ink thickeners and aggregates were adhered to the nozzle surface, and the nozzle was clogged.

  The above results are shown in Table 1.

  In the above-described embodiment, the present invention has been described with reference to an example in which the present invention is applied to an ink jet recording apparatus.

1 is a configuration diagram showing an outline of a mechanism part of an ink jet recording apparatus as an embodiment of an image forming apparatus according to the present invention including a head cleaning apparatus according to the present invention. It is side surface explanatory drawing of the mechanism part. FIG. 2 is an explanatory plan view of a head configuration of the recording apparatus. FIG. 3 is a schematic explanatory view for explaining the first embodiment of the head cleaning device according to the present invention. FIG. 5 is an explanatory diagram for explaining the operation of FIG. 4. It is typical explanatory drawing with which it uses for description of 2nd Embodiment of the head cleaning apparatus which concerns on this invention. It is typical explanatory drawing with which it uses for description of 3rd Embodiment of the head cleaning apparatus which concerns on this invention. It is typical explanatory drawing with which it uses for description of 4th Embodiment of the head cleaning apparatus which concerns on this invention. It is typical explanatory drawing with which it uses for description of 5th Embodiment of the head cleaning apparatus which concerns on this invention. It is explanatory drawing explaining the 1st example of the brush of the head cleaning apparatus which concerns on this invention. It is explanatory drawing explaining the 2nd example of the brush of the head cleaning apparatus which concerns on this invention. It is explanatory drawing explaining the 3rd example of the brush of the head cleaning apparatus which concerns on this invention. It is explanatory drawing explaining the 4th example of the brush of the head cleaning apparatus which concerns on this invention. It is a typical explanatory view of a head cleaning device concerning the 1st comparative example. It is a typical explanatory view of a head cleaning device concerning the 2nd comparative example. It is a typical explanatory view of a head cleaning device concerning the 3rd comparative example. It is typical explanatory drawing of the head cleaning apparatus which concerns on a 4th comparative example. It is a typical explanatory view of a head cleaning device concerning the 5th comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 13 ... Carriage 14 ... Head 14a ... Recording head 14s ... Processing liquid head 15 ... Liquid cartridge 37 ... Subsystem 41, 61 ... Cap 42, 62 ... Cleaning liquid injection spray 43, 63 ... Cleaning liquid cartridge 44, 64 ... Cleaning liquid injection pump 55 ... Brush 56 ... Brush moving means 60 ... Cleaning solution 67 ... Porous body

Claims (20)

  A head cleaning apparatus for cleaning by bringing a brush into contact with a nozzle surface of a droplet discharge head for discharging droplets from a nozzle, comprising cleaning liquid supply means for supplying a cleaning liquid containing a surfactant to the nozzle surface of the head A head cleaning device.   The head cleaning device according to claim 1, wherein the cleaning agent includes an antifoaming agent.   3. The head cleaning apparatus according to claim 1, wherein the cleaning agent includes an antiseptic / antifungal agent.   4. The head cleaning device according to claim 1, wherein the cleaning agent includes a rust preventive agent.   5. The head cleaning apparatus according to claim 1, wherein the cleaning agent includes a humectant.   6. The head cleaning apparatus according to claim 5, wherein the humectant is a water-soluble organic solvent.   7. The cleaning apparatus according to claim 1, wherein the cleaning liquid supply unit supplies the cleaning liquid directly to a nozzle surface.   8. The cleaning apparatus according to claim 7, wherein the cleaning liquid supply means directly supplies the cleaning liquid to the nozzle surface by spraying.   8. The cleaning apparatus according to claim 7, wherein the cleaning liquid supply means makes the porous body impregnated with the cleaning liquid contact the nozzle surface.   7. The head cleaning device according to claim 1, wherein the cleaning liquid is supplied to the brush surface after being supplied to the brush.   11. The head cleaning device according to claim 10, wherein the cleaning liquid is supplied to the brush by spraying.   11. The head cleaning apparatus according to claim 10, wherein the porous body impregnated with the cleaning liquid is supplied in contact with the brush.   11. The head cleaning device according to claim 10, wherein a part of the brush is immersed in the cleaning liquid and supplied.   7. The head cleaning device according to claim 1, wherein the cleaning liquid is supplied to the nozzle surface in a cleaning liquid scattering prevention chamber in close contact with the nozzle surface.   15. The head cleaning apparatus according to claim 14, wherein the cleaning liquid scattering prevention chamber is formed of a cap.   A liquid droplet ejection head for ejecting liquid droplets from a nozzle to form an image on a recording medium, a liquid cartridge containing liquid supplied to the liquid droplet ejection head, and a nozzle surface of the liquid droplet ejection head are cleaned 16. An image forming apparatus comprising: a head cleaning device that comprises a head cleaning device, wherein the head cleaning device is the head cleaning device according to claim 1.   17. The image forming apparatus according to claim 16, wherein the droplet discharge head discharges droplets using film boiling generated in the liquid by thermal energy generated by electrothermal conversion means.   18. The image forming apparatus according to claim 16, wherein the liquid is a recording liquid containing a color material.   The image forming apparatus according to claim 18, wherein the color material of the recording liquid is a pigment. 17. The image forming apparatus according to claim 16, wherein the recording liquid contains a coloring material and the processing liquid that does not contain a coloring material and generates agglomerates or insolubles by contact with the recording liquid. An image forming apparatus comprising a droplet discharge head.

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