JP2006240235A - Ink jet head cleaning device and ink jet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent ink from scattering by reducing the ink deposit quantity to an eradication member at the time of a meniscus formation. <P>SOLUTION: An ink jet recording apparatus comprises an ink jet head 1 which ejects the ink drop from a nozzle hole according to the driving of an actuator and an eradication member 3 which cleans the nozzle surface 1' of this ink jet head. The eradication member 3 performs the eradication operation of multiple times after the ink suction, at least, the eradication operation is performed by the non-contact with the nozzle surface 1' at the time of the 1st eradication (Fig. (A)), and at least, the eradication operation is performed by the contact with the nozzle surface 1' at the time of the last eradication (Fig. (B)). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an inkjet head cleaning device and an inkjet recording apparatus including the inkjet head cleaning device, and more particularly to maintenance and recovery of ink ejection performance of an inkjet head that ejects ink.

  In recent years, with the generalization of ink jet recording apparatuses, it is necessary to improve the image quality of plain paper as well as the image quality of conventional ink jet paper such as dye ink. For this reason, in order to prevent bleeding on plain paper, a highly viscous pigment-based ink is employed.

  In the case of pigment ink, as shown in the prior art example, early thickening and fixing occur and remain in the recovery device provided in the ink jet recording apparatus, resulting in deterioration of recovery performance. Further, ink that is scattered due to the elasticity of the wiping member when wiping the nozzle surface also tends to deteriorate due to an increase in the ink mass.

  Japanese Patent Laid-Open No. 2000-103071 (Patent Document 1) describes that the behavior of a wiping member is moderated in order to prevent ink scattering during wiping. However, in this case, the wiping operation is restricted at the wiping end, and sufficient wiping is not performed, and in the case of pigment ink, there may be a problem that the remaining ink accumulates.

Japanese Patent Laid-Open No. 2003-154681 (Patent Document 2) discloses that in a recording apparatus provided with both pigment ink and dye ink, the recovery performance of the head is deteriorated by dissolving and discharging the pigment ink with the dye ink. It is described to prevent.
Generally, black ink is configured as pigment ink, and other color ink is configured as dye ink. However, in order to improve the quality of color printing on plain paper, an increasing number of recording apparatuses use pigment ink even for color ink. For this reason, it may be impossible to prevent the pigment ink from being thickened and prevented from sticking with the dye ink.
For this reason, pigment ink scattered by wiping accumulates in the form of clay, and there is a problem that the movable part of the operation of the maintenance mechanism malfunctions or a problem that adheres to the nozzle surface and causes image defects.
JP 2000-103071 A JP 2003-154681 A

The present invention has been made in view of the above situation,
The object of the present invention is to reduce the amount of ink adhering to the wiping member during meniscus formation and prevent ink scattering.

  In the invention of Claim 2, it aims at reducing the frequency | count of wiping operation | movement with the structure of a wiping member.

  According to the third aspect of the present invention, it is an object to efficiently perform the ink removal operation.

  According to a fourth aspect of the present invention, the ink is prevented from accumulating on the wiping member.

  In the invention of claim 5, the object is to reduce ink remaining on the nozzle surface during the ink removal operation.

  The present invention has an object of performing a stable printing operation by mounting an ink jet cleaning device which prevents ink scattering.

  The invention of claim 1 includes an inkjet head that ejects ink droplets from nozzle holes, an inkjet head cleaning device that includes a wiping member that cleans the nozzle surface of the inkjet head, and a suction cap that sucks ink from the nozzles. In the maintenance and recovery device, the ink is a pigment-based ink, and the wiping member performs a wiping operation a plurality of times after sucking the ink, and at least does a wiping operation without contact with the nozzle surface during the first wiping. In the final wiping, the wiping operation is performed in contact with the nozzle surface.

  According to a second aspect of the present invention, there is provided an ink jet head that discharges ink droplets from a nozzle hole, an ink jet head cleaning device that includes a wiping member that cleans a nozzle surface of the ink jet head, and a suction cap that sucks ink from the nozzle. In the maintenance and recovery device, the ink is a pigment-based ink, and the wiping member is a first wiping member disposed at a position not in contact with the nozzle surface, and a second wiping member disposed at a position in contact with the nozzle surface. It is characterized by comprising.

  According to a third aspect of the present invention, in the second aspect of the present invention, the first wiping member and the second wiping member are arranged with a gap therebetween.

  The invention of claim 4 is characterized in that, in the invention of claim 2, a water repellent film is formed on a surface outside the elastic deformation region of the wiping member.

  A fifth aspect of the invention is characterized in that, in the first or second aspect of the invention, a water repellent film is formed on a nozzle surface of the ink jet head.

  The invention of claim 6 is an ink jet recording apparatus for recording an image on a recording medium by ejecting ink droplets from ejection holes, comprising the invention according to any one of claims 1 to 4. It is what.

  2. The ink jet head cleaning apparatus according to claim 1, wherein ink droplets on the ink jet head surface are wiped in a non-contact manner at least in the first wiping operation, so that the ink in the final wiping operation for wiping at least in contact with the nozzle surface. Scattering can be prevented.

  3. The ink jet head cleaning apparatus according to claim 2, wherein at least the first wiping member wipes ink droplets on the surface of the ink jet head in a non-contact manner. Can be prevented.

  In the ink jet head cleaning device according to claim 3, since the gap is provided between the first wiping member and the second wiping member, the ink penetrates between the gaps, and the ink removal amount at the first wiping member is reduced. This increases the amount of ink scattered on the second wiping member.

  In the ink jet head cleaning device according to claim 4, since the water repellent treatment is performed outside the elastic region of the wiping member, the ink removed by the wiping operation falls by its own weight, and the ink is deposited on the wiping member. Can be prevented.

  In the ink jet head cleaning device according to claim 5, since the surface of the ink jet head is subjected to water repellency treatment, the amount of ink that is hydrophilic to the first wiping member increases, and the ink scatters on the second wiping member. Can be prevented.

  In the ink jet recording apparatus according to the sixth aspect of the present invention, since the ink jet head cleaning device that prevents ink scattering is provided, it is possible to prevent malfunction due to ink accumulation and to ensure stable print quality.

FIG. 1 is a block diagram of a main part for explaining an embodiment of an ink jet head cleaning apparatus according to the present invention. As shown in FIG. 1 (A), the ink jet head cleaning device is a wiping member for wiping off ink 2 adhering to the ink. In the first wiping operation, the ink droplet 2 accumulated on the nozzle surface 1 'after the suction operation is removed. The first wiping operation is performed with the wiping member 3 raised to the raised position I (not in contact with the nozzle surface 1 ′), that is, with the nozzle surface 1 ′ and the interval Da. The first wiping operation is performed by moving the wiping member 3 arrow direction over the A ₁ segment. Incidentally, showing the ink 2 ₂ which is wiped A ₂ section and ink 2 ₁ remaining on the nozzle surface 1 'after wiping by the wiping member 3. Many ink 2 ₂ is eliminated by this operation. This first wiping operation is performed at least once.

As described above, after eliminating the large amount of ink 2 _second nozzle surface 1 'by the first wiping operation, as shown in FIG. 1 (B), carrying out the final wiping operation. In this final wiping operation, the wiping member 3 is raised to the raised position II, elevated position II gave a constant bite amount Db to the nozzle surface 1 ', in this condition, the wiping member 3 directions of arrows B ₁ section The wiping operation is performed by moving over the distance. B ₂ section, shows a state in which the person performing this wiping operation, and wiping the ink 2 ₁ which remains on the nozzle surface 1 'by this wiping operation, forms a meniscus in the nozzle hole. The nozzle surface 1 'is subjected to a water repellent treatment, so that hydrophilicity to the wiping member is improved.

FIG. 2 is a configuration diagram of a main part for explaining another embodiment of the present invention. This embodiment includes a first wiping member 4 in which the wiping member is disposed so as not to contact the nozzle surface 1 ′, It has the 2nd wiping member 5 arrange | positioned so that a fixed bite amount may be given to nozzle surface 1 ', and it has a fixed gap W between the 1st wiping member 4 and the 2nd wiping member 5, These 1st wiping members 4 and a second wiping member 5 moves over the section C ₁ to integrally arrow direction. The first wiping member 4 operates corresponding to the first wiping operation in FIG. 1, and the second wiping member 5 operates corresponding to the final wiping operation in FIG. 1. According to this embodiment, the first wiping member 5 1 wiping member ink 2 ₂ was eliminated by 4 penetrates by capillary forces between the gap W. By performing water-repellent treatment outside the elastic deformation area of the wiping member (lower part Q in the figure), the excluded ink is discharged by its own weight into a waste liquid tank (not shown) provided below.

  The water repellent film may be formed by vacuum deposition or may be applied after being dissolved in an appropriate solvent. Speaking of the former, for example, after evacuating the inside of the vacuum chamber to a predetermined degree of vacuum with a vacuum pump, the water-repellent material is vaporized at 400 ° C. and introduced into the vacuum chamber to adjust the vacuum atmosphere, The discharge electrode is supplied with electric power to cause an RF glow discharge, and the orifice surface of the liquid discharge head is surface-treated in a plasma atmosphere to form the water-repellent film on the orifice surface. Depending on the material and the degree of vacuum in the vacuum chamber, it is possible to form a water-repellent film at a low temperature of about room temperature to about 200 ° C. As for the latter, for example, a water-repellent material can be dissolved in an organic solvent and coated with a jig such as a wire bar or a doctor blade, or can be applied by spin coating with a spin coater or by spraying. It can also be dip coated (dipped) in a container filled with a coating solution.

As the water-repellent material, an organic compound having a fluorine atom, particularly an organic substance having a fluoroalkyl group, an organic silicon compound having a dimethylsiloxane skeleton, or the like can be used.
As the organic compound having a fluorine atom, fluoroalkylsilane, alkane having a fluoroalkyl group, cambonic acid, alcohol, amine and the like are desirable. Specifically, the fluoroalkylsilane includes heptadecafluoro-1,1,2,2-tetrahydrodecyltrimethoxysilane, heptadecafluoro-1,1,2,2-tetrahydrotrichlorosilane; fluoroalkyl Examples of the alkane having a group include octafluorocyclobutane, perfluoromethylcyclohexane, perfluoro-n-hexane, perfluoro-n-heptane, tetradecafluoro-2-methylpentane, perfluorododecane, perfluoroeucosan; Examples of the carboxylic acid having an alkyl group include perfluorodecanoic acid and perfluorooctanoic acid; examples of the alcohol having a fluoroalkyl group include 3, 3, 4, 4, 5, 5, 5-heptafluoro-2-pentanol; A with a fluoroalkyl group The emissions, heptadecafluoro-1,1,2,2-tetrahydro-decyl amine. Examples of organosilicon compounds having a dimethylsiloxane skeleton include α, w-bis (3-aminopropyl) polydimethylsiloxane, α, w-bis (3-glycidoxypropyl) polydimethylsiloxane, α, w-bis (vinyl). ) Polydimethylsiloxane and the like.

  As another water-repellent material, an organic compound having a silicon atom or an organic compound having an alkylsiloxane group can be used. Examples of the organic compound having an alkylsiloxane group include alkylsiloxane groups having two or more alkylsiloxane groups and cycloaliphatic epoxy groups in the molecule constituting the alkylsiloxane epoxy resin composition. The polymer compound (A) containing the structural unit represented by general formula (a) and (b) is mentioned.

The compound having the above structure also functions as a binder when used in combination with other water-repellent compounds. In other words, it improves the application suitability of the ink-repellent composition and also improves the workability as a dry coating film that improves the drying property after evaporation of the solvent.
The film thickness of the water repellent film is preferably 5 μm or less, more preferably 2 μm or less. When the film thickness exceeds 5 μm, drying of the coating film may be delayed, productivity may be deteriorated, and mechanical durability may be impaired, and peeling may occur when wiping is performed.

  FIG. 3 is a perspective view showing a main part of an ink jet recording apparatus to which the present invention is applied, and FIG. 4 is a side view showing a mechanism part of the recording apparatus. The ink jet recording apparatus is provided inside the recording apparatus main body 10. The printing mechanism unit 11 includes a carriage 12 movable in the main scanning direction, a recording head 13 including an inkjet head mounted on the carriage 12, and an ink cartridge that supplies ink to the recording head 13. 14 etc. A paper feed cassette (or a paper feed tray) 22 capable of stacking a large number of sheets 21 from the front side can be removably mounted on the lower part of the apparatus main body 10, and the sheets 21 can be manually fed. The manual feed tray 23 for paper can be opened, the paper 21 fed from the paper feed cassette 22 or the manual feed tray 23 is taken in, a required image is recorded by the printing mechanism unit 11, and then attached to the rear side. The paper is discharged to the discharged paper discharge tray 24.

Printing mechanism unit 11, slidable carriage 12 in non a guide member which is laterally placed on the left and right side plates and the main guide rod 15 ₁ and sub guide rod 15 ₂ shown in the main scanning direction (direction perpendicular to the paper surface in FIG. 3) In this carriage 12, a recording head 13 comprising an ink jet head for discharging ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk) is provided with a plurality of ink discharge ports ( Nozzles) are arranged in a direction crossing the main scanning direction, and are mounted with the ink droplet ejection direction facing downward. In addition, each ink cartridge 14 for supplying ink of each color to the recording head 13 is replaceably mounted on the carriage 12.

The carriage 12 is slidably fitted rear side (downstream in the sheet conveying direction) on the main guide rod 15 _1, slidably mounted front side (the sheet conveyance direction upstream side) to the slave guide rod 15 ₂ ing. Then, this order to the carriage 12 to move in the main scanning direction, and ChoSo the timing belt 18 between the _main scanning driving pulley 17 by the motor 16 is driven to rotate and a driven pulley 17 _2, the timing belt 18 The carriage 12 is fixed to the carriage 12, and the carriage 12 is reciprocated by forward and reverse rotation of the main scanning motor 16.

  On the other hand, in order to convey the paper 21 set in the paper feed cassette 22 to the lower side of the recording head 13, the paper feed roller 31 and the friction pad 32 for separating and feeding the paper 21 from the paper feed cassette 22 and the paper 21 are guided. A guide member 33 for conveying, a conveyance roller 34 for reversing and conveying the fed paper 21, a conveyance roller 35 pressed against the peripheral surface of the conveyance roller 34, and a feeding angle of the paper 21 from the conveyance roller 34 are defined. A tip roller 36 is provided. The conveyance roller 34 is rotationally driven by a sub-scanning motor 37 through a gear train.

  At the time of recording, the recording head 13 is driven according to the image signal while moving the carriage 12, thereby ejecting ink onto the stopped sheet 21 to record one line, and after the sheet 21 is conveyed by a predetermined amount, Record the line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 21 reaches the recording area, the recording operation is terminated and the paper 21 is discharged.

  A recovery device 100 (recovery device shown in FIG. 1 or FIG. 2) for recovering defective ejection of the recording head 13 is disposed at a position outside the recording area on the right end side in the movement direction of the carriage 12. The recovery device 100 includes a cap unit, a suction unit, and a cleaning unit. The carriage 12 is moved to the recovery device 100 side during printing standby, and the recording head 13 is capped by the capping unit, and the ejection port portion is kept in a wet state to prevent ejection failure due to ink drying. Further, by ejecting ink that is 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 discharge port (nozzle) of the recording head 13 is sealed by the capping unit, and bubbles and the like are sucked from the discharge port by the suction unit through the tube. 1 or 2 is removed by the cleaning means shown in FIG. 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.

It is a principal part block diagram for demonstrating one Example of the inkjet head cleaning apparatus by this invention. It is a principal part block diagram for demonstrating the other Example of this invention. 1 is a perspective view showing a main part of an ink jet recording apparatus to which the present invention is applied. FIG. 6 is a side view illustrating a mechanism unit of the recording apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Nozzle surface, 2 ... Ink, 3 ... Wiping member, 4 ... 1st wiping member, 5 ... 2nd wiping member, 10 ... Recording apparatus main body, 11 ... Printing mechanism part, 12 ... Carriage, 13 ... Recording head, 14 ... ink cartridge, 15 ₁ ... main guide rod, 15 ₂ ... slave guide rod, 17 ₁ ... drive pulley, 17 ₂ ... driven pulley, 18 ... timing belt, 21 ... paper, 22 ... paper feed cassette, 23 ... manual feed tray, 24: paper discharge tray, 31: paper feed roller, 32 ... friction pad, 33 ... guide member, 34 ... transport roller, 35 ... transport roller, 36 ... tip roller, 37 ... sub-scanning motor, 100 ... recovery device.

Claims (6)

In an inkjet head that ejects ink droplets from nozzle holes, an inkjet head cleaning device that includes a wiping member that cleans the nozzle surface of the inkjet head, and a maintenance and recovery device that includes a suction cap that sucks ink from the nozzles.
The ink is a pigment-based ink,
The wiping member performs a wiping operation a plurality of times after ink suction, and at least does the wiping operation without contact with the nozzle surface at the time of the first wiping, and at least does the wiping operation in contact with the nozzle surface at the time of the final wiping. An inkjet head cleaning device characterized by the above. In an inkjet head that ejects ink droplets from nozzle holes, an inkjet head cleaning device that includes a wiping member that cleans the nozzle surface of the inkjet head, and a maintenance and recovery device that includes a suction cap that sucks ink from the nozzles.
The ink is a pigment-based ink,
The ink-jet head cleaning apparatus according to claim 1, wherein the wiping member is composed of a first wiping member disposed at a position not in contact with the nozzle surface and a second wiping member disposed at a position in contact with the nozzle surface.   The inkjet head cleaning apparatus according to claim 2, wherein a gap is provided between the first wiping member and the second wiping member.   The inkjet head cleaning apparatus according to claim 2, wherein a water repellent film is formed on a surface outside the elastic deformation region of the wiping member.   The inkjet head cleaning apparatus according to claim 1, wherein a water repellent film is formed on a nozzle surface of the inkjet head.   An ink jet recording apparatus for recording an image on a recording medium by ejecting ink droplets from an ejection hole, comprising the ink jet head cleaning device according to claim 1. .