Inkjet recording method, and inkjet recording device

Abstract

To provide an inkjet recording method that can suppress deflection of discharging of ink from occurring even when using a recording head having a protective tape attached to a discharge port surface that is a water-repellent surface, and prevent the deflection of discharging of ink even when using the recording head for a long time.SOLUTION: An inkjet recording method records an image using an inkjet recording device equipped with means for wiping a discharge port surface 30 subjected to water-repellent processing. A protective tape that is peeled off when used is attached to the discharge port surface 30 of a recording head 12. The method has a first cleaning sequence including a first wiping step and a second wiping step in which the discharge port surface 30 is wiped using one wiper 20 in a blade shape, where in the first wiping step, the discharge port surface 30 is wiped with a middle part 25 of the wiper 20 and in the second wiping step, the discharge port surface 30 is wiped with an edge part of the wiper 20.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an inkjet recording method and an inkjet recording apparatus. [Background technology]

[0002] According to the inkjet recording method, images can be recorded on various recording media. In recent years, inkjet recording devices equipped with ink cartridges in which a recording head is built into an ink storage section that contains water-based ink have become widespread, with the aim of simplifying and miniaturizing the device configuration and shortening the preparation time until recording at the time of initial use. Since this ink cartridge is transported or stored in a state in which the water-based ink is filled up to the tip of the opening of the ejection port, the ink is prone to evaporating. In order to suppress such evaporation of ink, a protective tape having an adhesive layer formed of an adhesive is usually attached to the ejection port surface, and the ink cartridge in which the recording head is built is stored in a state in which the ejection port is blocked.

[0003] In addition, in the business field, the inkjet recording method is also used when recording full-color text including charts and diagrams on recording media such as plain paper. In such applications, there is an increasing need for inks containing resins that are less susceptible to deterioration in image quality due to irregular ejection and that can record images with excellent water resistance and abrasion resistance.

[0004] Inkjet recording is a method of recording an image by ejecting liquid ink from fine nozzles of a recording head and directly applying it to a recording medium. For this reason, during image recording, minute ink droplets other than the ink involved in recording may float in the atmosphere. Fine ink droplets such as mist that are not involved in recording may adhere to the periphery of the nozzles on the surface (discharge port surface) of the recording head where the nozzles are formed. When minute ink droplets adhere to the discharge port surface, the straightness of the ink is hindered and the discharge direction is distorted, so-called "discharge deviation" occurs, and the ink discharge accuracy decreases, making it easy for the quality of the recorded image to decrease. Furthermore, since the amount of ink droplets adhering to the discharge port surface tends to increase when recording is performed for a long period of time, the quality of the image further decreases with the recording time.

[0005] In order to prevent the occurrence of irregular ejection, for example, an inkjet recording device has been proposed that is equipped with a cleaning device that wipes the ejection port with the middle part of a first wiper that is bent significantly, and then wipes the ejection port with the edge part of a second wiper (Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2006-205715 A Summary of the Invention [Problem to be solved by the invention]

[0007] The present inventors have studied an inkjet recording device equipped with a cleaning device proposed in Patent Document 1. Specifically, an ink cartridge was prepared incorporating a recording head whose discharge port surface was treated to be water-repellent and whose discharge port surface (water-repellent surface) was covered with a protective tape that was peeled off at the start of recording, and an aqueous ink containing a pigment and a resin was stored in the ink storage section. Then, the protective tape of this recording head was peeled off and the recording head was set in an inkjet recording device, and an image was recorded. As a result, it was found that discharge irregularities were likely to occur immediately after the protective tape was peeled off (immediately after opening). On the other hand, when an aqueous ink containing a self-dispersing pigment but no resin was used, no discharge irregularities were observed immediately after opening. In addition, an inkjet recording device was prepared that had a recording head whose discharge port surface was blocked with a cap without a protective tape attached to the discharge port surface (water-repellent surface), and an image was recorded using an aqueous ink containing a pigment and a resin, and no discharge irregularities were observed immediately after removing the cap.

[0008] Therefore, an object of the present invention is to solve the problems that arise when using a recording head with a protective tape attached to the water-repellent discharge port surface, and a recording device equipped with a wiping means for the discharge port surface, and using an aqueous ink containing a pigment and a resin. That is, even in such a case, the object is to provide an inkjet recording method that suppresses the occurrence of irregular discharge of ink immediately after peeling off the protective tape (immediately after opening), and is less likely to cause irregular discharge even after long-term use. Another object of the present invention is to provide an inkjet recording device used in this inkjet recording method. [Means for solving the problem]

[0009] That is, according to the present invention, there is provided an inkjet recording method comprising: an inkjet recording device having a water-repellent treated ejection port surface, the inkjet recording device comprising: an aqueous ink containing a pigment and a resin; an ink storage section for storing the aqueous ink; a recording head having an ejection port surface formed with ejection ports for ejecting the aqueous ink supplied from the ink storage section; and a wiping means for wiping the ejection port surface; and a step of applying the aqueous ink ejected from the ejection port to a recording medium to record an image, the inkjet recording method comprising: an inkjet recording device having a water-repellent treated ejection port surface, the inkjet recording device comprising: an ink storage section for storing the aqueous ink; Effect of the Invention

[0010] According to the present invention, a recording head having a protective tape attached to the water-repellent discharge port surface and a recording device having a wiping means for the discharge port surface are used to solve the problems that arise when using an aqueous ink containing a pigment and a resin. That is, even in such a case, it is possible to provide an inkjet recording method that suppresses the occurrence of irregular discharge of ink immediately after peeling off the protective tape (immediately after opening), and is less likely to cause irregular discharge even after long-term use. Furthermore, according to the present invention, it is possible to provide an inkjet recording device used in this inkjet recording method. [Brief description of the drawings]

[0011] [Figure 1] 1 is a perspective view showing a schematic internal structure of an inkjet recording apparatus according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a perspective view illustrating an example of a maintenance unit. [Diagram 3] FIG. 2 is a perspective view illustrating an example of a recording unit. [Figure 4] 5A to 5C are diagrams illustrating the movement of a wiper during a cleaning operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention will be described in more detail below with reference to preferred embodiments. In the present invention, when the compound is a salt, the salt is present in the ink in the form of dissociation into ions, but for convenience, it is expressed as "containing a salt." In addition, water-based ink for inkjet printing may be simply referred to as "ink." Physical property values ​​are values ​​at room temperature (25°C) unless otherwise specified.

[0013] The present inventors prepared an ink cartridge in which a recording head is incorporated in an ink storage section having an ejection port surface where an ejection port for ejecting ink is formed, and the ejection port surface is treated to be water repellent. Then, using the prepared ink cartridge, an analysis was conducted on ejection irregularities that occur when an ink containing a pigment and a resin is ejected from a recording head immediately after peeling off a protective tape and opening the package. An ink cartridge in which an ink storage section and a recording head are integrally formed is usually stored in a state where a protective tape having an adhesive layer is attached to the ejection port surface of the recording head and the ejection port is blocked in order to suppress evaporation of the ink. Then, at the time of first use (at the start of initial use), the ink cartridge packed in a sealed container is opened, the protective tape is peeled off, and the ink cartridge is mounted on a recording device to start recording an image. However, when the protective tape is peeled off, a part of the adhesive forming the adhesive layer may remain attached to the ejection port surface, and it was found that the remaining adhesive causes ejection irregularities of the ink.

[0014] However, when dye ink or pigment ink not containing resin is used, it was found that irregular ejection does not occur even if adhesive is attached to the ejection port surface of the recording head. When the ejection port surface of the recording head where irregular ejection of ink occurred was observed after peeling off the attached protective tape, adhesive residue was confirmed. In addition, the contact angle of the ejection port surface with various inks before the protective tape was attached, and the contact angle of the ejection port surface with various inks after the protective tape was attached and peeled off were measured. As a result, it was found that the contact angle with the ink containing resin was uniquely different before and after the protective tape was attached. In other words, it is considered that the ejection port surface with the adhesive attached is easily wetted by the ink containing resin, causing irregular ejection.

[0015] When using a recording unit in which an ink container is set in a head cartridge equipped with a recording head, there is no need to suppress the evaporation of ink from the ejection ports, which is necessary in an ink cartridge in which a recording head is built into an ink container. Therefore, when using a recording unit in which an ink container is set in a head cartridge equipped with a recording head, irregular ink ejection caused by residual adhesive does not occur.

[0016] The present inventors further studied the wiping conditions of the ejection port surface. As a result, they found that the following configuration suppresses the occurrence of ejection irregularities immediately after peeling off the protective tape, and also makes ejection irregularities less likely to occur even after long-term use, and thus arrived at the present invention. That is, in the inkjet recording method of the present invention, an inkjet recording device is used that includes an ink containing a pigment and a resin, an ink storage section that stores the ink, a recording head incorporated in the ink storage section, and a wiping means that performs wiping. The recording head is attached to the ink storage section, and has an ejection port surface in which ejection ports for ejecting ink are formed, and this ejection port surface is treated to be water-repellent. The wiping means is a means for wiping the ejection port surface of the recording head. A protective tape having an adhesive layer formed of an adhesive is attached to the ejection port surface of the recording head in order to suppress evaporation of ink from the ejection ports, and this protective tape is peeled off when the inkjet recording device or the recording head is used for the first time. The inkjet recording method of the present invention has a first cleaning sequence including a first wiping step and a second wiping step that are performed successively to wipe the ejection port surface with a single blade-shaped wiper. The first wiping step is a step of bending the wiper to wipe the ejection port surface with the middle part of the wiper, and the second wiping step is a step of wiping the ejection port surface with the edge part of the wiper.

[0017] In the first wiping step, the wiper is bent relatively greatly, and the wiper's midsection is brought into sliding contact with the discharge port surface. This allows the ink droplets on the discharge port surface to spread and blend with the adhesive that has adhered thereto. In the subsequent second wiping step, the wiper is not bent very greatly or barely at all, and the wiper's edge portion (part other than the midsection) is brought into contact with the discharge port surface for wiping. This allows the mixture of ink droplets and adhesive that has been blended in the first wiping step to be scraped off. A large amount of pigment is also attached to the discharge port surface. The pigment, which is a hard granular material, is dragged by the wiper, scraping off the firmly attached adhesive that cannot be scraped off by the wiper's edge alone, so to speak, acting as an "abrasive." In this way, the ink droplets are spread and blended with the adhesive in the first wiping step, in which the wiper's midsection is used for wiping, and then the adhesive can be efficiently scraped off in the second wiping step, in which the wiper's edge is used for wiping. As a result, it is believed that uneven discharge immediately after opening is suppressed, and uneven discharge is less likely to occur even after long-term use.

[0018] If the second wiping step is not performed and only the first wiping step is performed, the adhesive cannot be scraped off and removed, making it impossible to prevent irregular ejection. Also, if the first wiping step is not performed and only the second wiping step is performed, the ink droplets and the adhesive do not blend well with each other, making it impossible to efficiently remove the adhesive, making it impossible to prevent irregular ejection.

[0019] <Inkjet recording method and inkjet recording apparatus> The inkjet recording method of the present invention is a recording method using an inkjet recording device including an ink, an ink storage section for storing the ink, a recording head, and a wiping means for wiping the nozzle surface of the recording head. The ink contains a pigment and a resin. The recording head is a recording head incorporated in the ink storage section, which has a nozzle surface formed with nozzles for discharging ink supplied from the ink storage section, and the nozzle surface is water-repellent treated. The inkjet recording method of the present invention includes a step of applying ink discharged from the nozzles of the recording head to a recording medium to record an image. A protective tape having an adhesive layer formed of an adhesive, which is peeled off when used, is attached to the nozzle surface of the recording head. Furthermore, the inkjet recording method of the present invention includes a first cleaning sequence including a first wiping step and a second wiping step that are performed consecutively to each other, in which the nozzle surface is wiped using a single blade-shaped wiper. The first wiping step is a step of bending the wiper to wipe the nozzle surface with the midsection of the wiper. And the second wiping step is a step of wiping the nozzle surface with the edge portion of the wiper.

[0020] The inkjet recording apparatus of the present invention includes ink, an ink storage unit that stores the ink, a recording head, and a wiping means that wipes the discharge port surface. The ink contains a pigment and a resin. The recording head is a recording head that is incorporated in the ink storage unit and has a discharge port surface in which discharge ports for discharging ink supplied from the ink storage unit are formed, and the discharge port surface is water-repellent treated. The inkjet recording method performed using this recording apparatus includes a step of applying ink discharged from the discharge ports of the recording head to a recording medium to record an image. A protective tape having an adhesive layer formed of an adhesive, which is peeled off when used, is attached to the discharge port surface of the recording head. Furthermore, the inkjet recording method includes a first cleaning sequence including a first wiping step and a second wiping step that are performed consecutively to each other, in which the discharge port surface is wiped using one blade-shaped wiper. The first wiping step is a step of bending the wiper to wipe the discharge port surface with the middle part of the wiper. And the second wiping step is a step of wiping the discharge port surface with the edge part of the wiper.

[0021] (Inkjet recording device) FIG. 1 is a perspective view showing a schematic internal structure of an embodiment of an ink recording device of the present invention. As shown in FIG. 1, an inkjet recording device 1010 of this embodiment includes a carriage 1020, a transport unit 1060, and a maintenance unit 1030. A recording head that ejects ink and an ink cartridge (not shown) are mounted on the carriage 1020. The transport unit 1060 is a unit that transports a recording medium fed from a paper feed unit 1070. The maintenance unit 1030 is a unit that performs maintenance on the recording head mounted on the carriage. The inkjet recording device 1010 further includes a tube 1090 that supplies ink to the recording head, and a main tank 1080 that contains ink. The transport unit 1060 is disposed at one end of the carriage carrying the recording head in the main scanning direction 21, and the maintenance unit 1030 is disposed at the other end of the main scanning direction 21. Drive from a drive source (not shown) of the transport unit 1060 is transmitted to the maintenance unit 1030 by a drive train.

[0022] The recording medium, which is fed one by one from the paper feed unit 1070, is transported by the transport unit 1060 in the discharge direction 11 of the recording medium. The carriage 1020 carrying the recording head performs a reciprocating motion in a direction (main scanning direction 21) substantially perpendicular to the discharge direction 11 of the recording medium, while ejecting ink from the recording head to perform recording on the recording medium. When performing recording, the carriage 1020 starts recording from the maintenance unit 1030 side, moves to the transport unit 1060 side, turns around and returns to the maintenance unit 1030 side. At the position of the maintenance unit 1030, preliminary ejection is performed from the recording head into a cap 1031 inside the maintenance unit. This reciprocating motion is regarded as one scan of the carriage 1020, and is repeated multiple times on the recording medium to record an image over the entire recording medium.

[0023] 2 is a perspective view showing a schematic example of a maintenance unit. The inkjet recording device is equipped with a black recording head and three color recording heads. A cap 1031 and a wiper 1032 are provided for each recording head. When the cam slider 1033 is actuated and the cam surface of the cam slider 1033 comes into contact with the follower surface of each member, each member operates independently.

[0024] The inkjet recording device preferably further includes a second ink storage unit such as a main tank having a larger capacity than the ink storage unit (first ink storage unit) such as a sub-tank, and a tube through which ink flows between the second ink storage unit and the ink storage unit. Considering the usage mode in remote work at home, it is important to reduce the frequency of replacing the ink cartridge as well as to reduce the size of the device. For this reason, by further providing a second ink storage unit such as a main tank, it is possible to reduce the frequency of ink replacement while avoiding an increase in the size of the device body. Hereinafter, an inkjet recording device in which only a first ink storage unit such as a sub-tank bonded to the recording head is provided as an ink storage unit is also referred to as a "first device configuration". In the case of the first device configuration, when the ink stored inside the ink storage unit is consumed, it is replaced with another ink storage unit (ink storage unit filled with ink). Therefore, compared to the second device configuration, the main tank and tube can be omitted, and the weight of the inkjet recording device can be reduced. An inkjet recording device further provided with a second ink containing unit such as a main tank having a larger capacity than the sub-tank as an ink containing unit is also referred to as a "second device configuration." In the case of the second device configuration, for example, by forming a connection part for a tube on the tank lid 33 of the recording unit 8 shown in FIG. 3, the ink containing unit 10 and the second ink containing unit such as the main tank can be connected.

[0025] In the case of the second device configuration, the frequency of ink replacement is reduced compared to the first device configuration, so that the period during which the ink is held in a stationary state in the main tank is longer. In addition, in the case of pigment ink, the pigment is more likely to settle if the period during which the ink is held in a stationary state is longer. The decrease in ejection performance due to adhesion occurs due to the ink drying in the flow path and the pigment coagulating, so it becomes more noticeable when an ink with a high pigment content is used. Depending on the usage conditions, the ejection irregularity after long-term use of the second device configuration is often inferior to the ejection irregularity after long-term use of the first device configuration. In contrast, in the inkjet recording method of the present invention, it is possible to suppress the ejection irregularity even in the case of the second device configuration, and it is possible to achieve both a reduction in the frequency of ink replacement and suppression of the ejection irregularity after long-term use.

[0026] FIG. 3 is a perspective view showing a schematic example of a recording unit (ink cartridge). As shown in FIG. 3, the recording unit 8 has an ink storage section 10, which is a housing formed of a material such as a thermoplastic resin, and a recording head 12 incorporated in the ink storage section 10. That is, the recording head 12 is formed integrally with the ink storage section 10. Since the recording head 12 is attached to the ink storage section 10 without any other member, the entire recording unit 8 is made small and lightweight. By using such a recording unit 8, the entire inkjet recording device can be made small and lightweight. Examples of the heat sink include those made of a material such as a metal oxide such as alumina. It is not necessary to interpose other members such as a heat sink between the ink storage section 10 and the recording head 12, but an adhesive layer formed of an adhesive or the like for fixing the recording head 12 to the ink storage section 10 may be present. The ink storage section 10 contains ink containing a pigment and a resin. The recording head 12 has an ejection port surface 30 in which ejection ports for ejecting ink supplied from the ink storage section 10 are formed. A protective tape 50 having an adhesive layer formed of an adhesive, which is peeled off when the ink cartridge is first used, is attached to the ejection port surface 30 of the recording head 12. By providing a tab 40 as a non-adhesive portion that is not attached to the recording head at the end of the protective tape 50, the protective tape can be easily peeled off.

[0027] The ink ejection method of the recording head includes a method of ejecting ink by applying mechanical energy generated by a piezoelectric element or the like to the ink, and a method of ejecting ink by applying thermal energy generated by an electrothermal converter (heater) or the like to the ink. Either ink ejection method may be adopted, but the method of ejecting ink by applying thermal energy to the ink is more preferable.

[0028] The discharge port surface of the recording head is treated to be water-repellent. Examples of methods for treating the discharge port surface to be water-repellent include a method of applying a water-repellent material by spraying, and a method of attaching a water-repellent material by vacuum deposition or plasma polymerization. The water repellency of the discharge port surface can be evaluated by measuring the contact angle of water. If the contact angle of water is 70° or more, it can be determined to be "water-repellent", and it is preferable that the contact angle of water is 90° or more. The contact angle with water can be measured using pure water (ion-exchanged water) and a general contact angle meter. Examples of the contact angle meter include an automatic contact angle measuring instrument (product name "CA-W", manufactured by Kyowa Interface Science).

[0029] Examples of the water-repellent material for the water-repellent treatment of the discharge port surface include compounds of fluorine-based resins. The water-repellent surface is preferably formed as a uniform resin film made of these materials, and this resin film preferably does not contain metals such as nickel. Examples of the fluorine-based resin include polytetrafluoroethylene resin and fluorine resins having a ring structure. Specific examples of the fluorine-based resin compound include those under the trade name "Polyflon PTFE" (manufactured by Daikin Industries), those under the trade name "Teflon (registered trademark) PTFE" (manufactured by DuPont), and those under the trade name "Cytop" (manufactured by Asahi Glass). In addition, other resins containing fluorine atoms, such as fluorinated epoxy resins, fluorinated polyimide resins, fluorinated polyamide resins, fluorinated acrylic resins, fluorinated urethane resins, fluorinated siloxane resins, and modified resins of these, can be used.

[0030] As the water-repellent material, a compound containing a silicon (Si) atom or a silicone-based resin may be used. Among them, it is preferable to use a condensate of a hydrolyzable silane compound having a fluoroalkyl group and a hydrolyzable silane compound having a cationic polymerizable group as the water-repellent material, since high water repellency and durability can be obtained. In addition, a resin obtained by curing the condensate by irradiation of active energy rays such as ultraviolet rays may be used. These hydrolyzable silane compounds have a hydrolyzable group such as an alkoxy group in their molecular structure. Examples of the cationic polymerizable group include a cyclic ether group and a cyclic vinyl ether group.

[0031] The protective tape is a member used to suppress evaporation of evaporable components in the ink, such as water, from evaporating from the nozzles of the recording head. The protective tape has an adhesive layer formed of an adhesive. Examples of the adhesive include silicone-based adhesives, acrylic-based adhesives, rubber-based adhesives, and urethane-based adhesives. Among them, silicone-based adhesives or acrylic-based adhesives are preferred, and acrylic-based adhesives are more preferred. Rubber-based adhesives generally have low strength. In addition, urethane-based adhesives may deteriorate due to the ink, and may peel off during storage and become easily dissolved in the ink. As a result, liquid components such as water in the ink may evaporate, and pigments and resins may aggregate in the ink flow path, which may cause ejection irregularities. In contrast, acrylic-based adhesives are preferred because the contact angle with the ink on the ejection port surface after peeling is less likely to decrease compared to other adhesives. The adhesive layer is formed on the surface of a sheet-like or film-like substrate, for example. Resin materials such as polyethylene terephthalate (PET) can be used as the substrate.

[0032] It is preferable that the acrylic adhesive contains a metal chelate crosslinking agent and that the pH of the ink at 25° C. is 8.6 or more. When an acrylic adhesive containing a metal chelate crosslinking agent is in contact with an ink having a high pH for a long time, the coordinated metal is released and the adhesive is easily deteriorated. As a result, the adhesive is easily wiped off by a wiper, which is preferable.

[0033] The inkjet method of this embodiment has a first cleaning sequence in which a blade-shaped wiper is used to wipe the discharge port surface of the recording head. This first cleaning sequence includes a first wiping step and a second wiping step that are performed consecutively. FIG. 4 is a diagram for explaining the movement of the wiper during the cleaning operation. (a) is a schematic diagram for explaining the movement of the wiper in the first wiping step, and (b) is a schematic diagram for explaining the movement of the wiper in the second wiping step. In the first wiping step, as shown in FIG. 4(a), the penetration amount P1 of the wiper with respect to the recording head 12 is set to a predetermined value by changing the height of the carriage on which the recording head 12 is mounted, and the wiper (wiper 15 before bending) is bent relatively greatly. Then, the bent portion 25 of the wiper 20 wipes the discharge port surface 30 of the recording head 12. This allows the ink droplets on the discharge port surface 30 to spread and blend with the attached adhesive 60.

[0034] In the second wiping step, as shown in Fig. 4(b), the edge of the wiper 20 wipes the ejection port surface 30 of the recording head 12. In the second wiping step, for example, the carriage is positioned higher than in the first wiping step, and the penetration amount P2 of the wiper into the recording head 12 is set to be smaller than the penetration amount P1 of the wiper in the first wiping step. This makes it possible to scrape off the mixture 65 of ink droplets and adhesive that has been blended in the first wiping step.

[0035] The penetration depth P1 of the wiper during the first wiping step is preferably 1.8 mm or less (FIG. 4(a)). If the penetration depth P1 of the wiper exceeds 1.8 mm, the force applied by contact increases, and the discharge port surface may become easily damaged. Furthermore, the water-repellent surface may be worn away by prolonged use, and the effect of suppressing uneven discharge may decrease. The penetration depth P1 of the wiper during the first wiping step is preferably 1.0 mm or more. The penetration depth P2 of the wiper during the second wiping step is preferably 0.3 mm or more (FIG. 4(b)). If the penetration depth P2 of the wiper is less than 0.3 mm, the efficiency of removing adhesive and the like may decrease slightly, and the effect of suppressing uneven discharge may decrease. The penetration depth P2 of the wiper during the second wiping step is preferably less than 1.0 mm. In particular, it is preferable that the penetration amount of the wiper in the first wiping step is 1.0 mm or more and 1.8 mm or less, and that the penetration amount of the wiper in the second wiping step is 0.3 mm or more and 1.0 mm or less.

[0036] The interval between the end of the first wiping step and the start of the second wiping step is preferably 5 seconds or more and 15 seconds or less. If the interval (time difference) is less than 5 seconds, the ink spread on the discharge port surface by the first wiping step may not be sufficiently compatible with the adhesive, and the efficiency of removing the adhesive and the like may be slightly reduced, and the effect of suppressing irregular discharge may be slightly reduced. On the other hand, if the interval (time difference) is more than 15 seconds, liquid components such as water in the ink attached to the discharge port surface may evaporate, making the ink more likely to stick. As a result, the efficiency of removing the adhesive and the like may be slightly reduced, and the effect of suppressing irregular discharge may be slightly reduced.

[0037] It is preferable to perform the first wiping step and the second wiping step two or more times each. If the first wiping step is performed less than two times, the ink droplets on the ejection port surface may not spread sufficiently, and the effect of suppressing irregular ejection may be reduced. Also, if the second wiping step is performed less than two times, it may be difficult to sufficiently remove the adhesive or the like attached to the ejection port surface, and the effect of suppressing irregular ejection may be reduced.

[0038] The material of the wiper is preferably one having rubber elasticity, for example, a rubber material (urethane rubber) formed of urethane resin. The thickness of the wiper is preferably 0.5 mm or more and 1.5 mm or less, more preferably 0.8 mm or more and 1.2 mm or less. If the thickness of the wiper is less than 0.5 mm, the efficiency of removing adhesives and the like may be slightly reduced. On the other hand, if the thickness of the wiper is more than 1.5 mm, the discharge port surface may be easily scratched. And, the water-repellent surface may be scraped off by long-term use, and the effect of suppressing discharge distortion may be reduced. The height of the wiper (the length from the fixed position of the wiper to the tip of the wiper) is preferably 5.0 mm or more and 20.0 mm or less, more preferably 5.0 mm or more and 15.0 mm or less.

[0039] The speed at which the discharge port surface is wiped using a wiper is preferably 100 mm / s or more and 150 mm / s or less. If the wiping speed is less than 100 mm / s, the discharge port surface may be easily damaged. Furthermore, the water-repellent surface may be scraped off by long-term use, and the effect of suppressing uneven discharge may decrease. On the other hand, if the wiping speed exceeds 150 mm / s, the efficiency of removing adhesive and the like may decrease slightly, and the effect of suppressing uneven discharge may decrease. The wiping speeds in the first wiping step, the second wiping step, and the third wiping step described later may be set within the above ranges, and may be the same or different.

[0040] It is preferable to execute the first cleaning sequence at least immediately after peeling off the protective tape. Specifically, it is preferable to execute the first cleaning sequence after peeling off the protective tape and before recording. If a certain amount of time has passed since peeling off the protective tape, the adhesive remaining on the ejection port surface may dry and adhere, making it difficult to remove. This may reduce the effect of suppressing irregular ejection.

[0041] The inkjet recording method of this embodiment preferably further includes a second cleaning sequence that is executed after the first cleaning sequence. This second cleaning sequence preferably includes a third wiping step of wiping the ejection port surface with an edge of a wiper while heating the recording head. This third wiping step can be performed in the same procedure as the above-mentioned second wiping step, except for heating the recording head. By wiping the recording head while heating it, the adhesive that has deteriorated due to heat can be easily peeled off, thereby improving the adhesive removal efficiency.

[0042] To heat the recording head, a heating means capable of heating the ink in the recording head to a temperature higher than the recording environment temperature such as room temperature (25°C) may be used. Examples of such a heating means include a heater for adjusting the ink temperature arranged in contact with the recording head, and a heater for ink ejection. To heat the ink using a heater for ink ejection, for example, a current that does not eject the ink may be repeatedly passed through the heater. The temperature of the ink in the recording head may be higher than the environment temperature (25°C), and is preferably 40°C to 70°C, and more preferably 50°C to 70°C.

[0043] It is preferable that the first wiping step is performed only in the first cleaning sequence. In other words, it is preferable that the second cleaning sequence does not substantially include a step of wiping the discharge port surface with the bottom of the wiper by bending the wiper significantly. If the step of wiping the discharge port surface with the bottom of the wiper by increasing the penetration amount of the wiper is also performed in the second cleaning sequence, the discharge port surface may be easily damaged. In addition, the water-repellent surface may be worn down by long-term use, and the effect of suppressing discharge irregularities may decrease. It is preferable to wipe the discharge port surface with the edge of the wiper (perform the second wiping step) after performing a recovery operation of the recording head by suction or recovery.

[0044] (Water-based ink) The inkjet recording method of the present invention includes a step of recording an image by applying the ink containing a pigment and a resin to a recording medium, the ink being ejected from an ejection port. The ink includes, for example, black ink, cyan ink, magenta ink, and yellow ink. In the present invention, it is sufficient to perform a step of applying the ink to a recording medium, and it is not necessary to perform a separate process (a step of applying a reaction liquid that reacts with the ink, a step of curing the image by irradiation with active energy rays, a step of heating the image, etc.). Therefore, the ink does not need to contain a reactant or a component that is cured by active energy rays, and it is also not necessary to use the ink and the reaction liquid in combination. The components constituting the ink will be described below.

[0045] [Colorant] A pigment is used as the coloring material of the ink. By using an ink containing a pigment, the adhesive firmly attached to the discharge port surface can be scraped off. Examples of the pigment include inorganic pigments such as carbon black; and organic pigments such as azo pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, imidazolone pigments, diketopyrrolopyrrole pigments, dioxazine pigments, and perinone pigments. Of these, it is preferable to use carbon black. Since carbon black is particularly hard among pigments, by using an ink containing carbon black, the adhesive attached to the discharge port surface can be scraped off more efficiently.

[0046] The pigment content (mass %) in the aqueous ink is preferably from 0.50 to 10.00 mass %, and more preferably from 1.00 to 8.00 mass %, based on the total mass of the ink.

[0047] Examples of pigment dispersion methods include resin-dispersed pigments that use a resin (resin dispersant) as a dispersant, and self-dispersed pigments in which hydrophilic groups are bonded to the pigment particle surface. In addition, resin-bonded pigments in which organic groups containing a resin are chemically bonded to the pigment particle surface, and microcapsule pigments in which the pigment particle surface is coated with a resin, etc. can be used. Among these, it is particularly preferable to use a resin-dispersed pigment in which a resin dispersant having a hydrophobic portion and a hydrophilic portion is used, the hydrophobic portion of the resin dispersant is adsorbed to the pigment particle surface, and the pigment is dispersed by the hydrophilic portion.

[0048] As the resin dispersant for dispersing the pigment in the aqueous medium, it is preferable to use one that can disperse the pigment in the aqueous medium by the action of anionic groups. As the resin dispersant, a resin described below, especially a water-soluble resin, can be used. When a resin-dispersed pigment is used, the content (mass%) of the pigment in the ink is preferably 0.3 to 10.0 times the content (mass%) of the resin dispersant in terms of mass ratio.

[0049] As the self-dispersing pigment, an anionic group such as a carboxylic acid group, a sulfonic acid group, or a phosphonic acid group can be used, which is bonded to the particle surface of the pigment directly or via another atomic group (-R-). The anionic group may be either an acid type or a salt type, and when it is a salt type, it may be either a partially dissociated state or a completely dissociated state. When the anionic group is a salt type, examples of the cation that serves as the counter ion include an alkali metal cation, ammonium, and organic ammonium. Specific examples of the other atomic group (-R-) include a linear or branched alkylene group having 1 to 12 carbon atoms; an arylene group such as a phenylene group or a naphthylene group; a carbonyl group; an imino group; an amide group; a sulfonyl group; an ester group; and an ether group. In addition, it may be a group that is a combination of these groups.

[0050] [resin] The ink contains a resin such as a water-soluble resin. The content (mass%) of the resin in the ink is preferably 0.10% by mass or more and 20.00% by mass or less, and more preferably 0.50% by mass or more and 15.00% by mass or less, based on the total mass of the ink. The resin can be added to the ink (i) to stabilize the dispersion state of the pigment, that is, as a resin dispersant or its auxiliary. Also, (ii) to improve various properties of the recorded image. Examples of the form of the resin include block copolymers, random copolymers, graft copolymers, and combinations thereof. The resin may be a water-soluble resin that can be dissolved in an aqueous medium, or may be resin particles that are dispersed in an aqueous medium. Among them, a water-soluble resin is preferred, and the water-soluble resin is preferably a resin dispersant for dispersing the pigment.

[0051] Examples of the resin include acrylic resin, urethane resin, and olefin resin. Among them, acrylic resin and urethane resin are preferred, and acrylic resin is more preferred. The acrylic resin is preferably one having a hydrophilic unit as a hydrophilic part and a hydrophobic unit as a hydrophobic part as a constituent unit. The hydrophilic unit is a unit having a hydrophilic group such as an anionic group. The hydrophilic unit can be formed, for example, by polymerizing a hydrophilic monomer having a hydrophilic group. Examples of the hydrophilic monomer having a hydrophilic group include acidic monomers having a carboxylic acid group such as (meth)acrylic acid, itaconic acid, maleic acid, and fumaric acid; anionic monomers such as anhydrides and salts of these acidic monomers; and the like. Examples of the cations constituting the salts of the acidic monomers include ions such as lithium, sodium, potassium, ammonium, and organic ammonium. The hydrophobic unit is a unit that does not have a hydrophilic group such as an anionic group. The hydrophobic unit can be formed, for example, by polymerizing a hydrophobic monomer that does not have a hydrophilic group such as an anionic group. Examples of hydrophobic monomers include monomers having an aromatic ring, such as styrene, α-methylstyrene, and benzyl (meth)acrylate; and (meth)acrylic acid ester monomers, such as methyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.

[0052] Among them, acrylic resins having a hydrophilic unit derived from (meth)acrylic acid and a hydrophobic unit derived from at least one monomer selected from the group consisting of a monomer having an aromatic ring and a (meth)acrylic acid ester monomer are preferred. In particular, acrylic resins having a hydrophilic unit derived from (meth)acrylic acid and a hydrophobic unit derived from at least one monomer of styrene and α-methylstyrene are preferred. These acrylic resins are easily interacted with pigments, and therefore can be suitably used as resin dispersants for dispersing pigments.

[0053] The urethane resin can be obtained, for example, by reacting a polyisocyanate with a polyol. In addition, a chain extender may be further reacted with the urethane resin. Examples of the olefin resin include polyethylene and polypropylene.

[0054] In this specification, "a resin is water-soluble" means that when the resin is neutralized with an alkali equivalent to the acid value, it exists in an aqueous medium in a state in which it does not form particles whose particle size can be measured by dynamic light scattering. Whether or not a resin is water-soluble can be determined according to the following method. First, a liquid (resin solid content: 10 mass%) containing a resin neutralized with an alkali (sodium hydroxide, potassium hydroxide, etc.) equivalent to the acid value is prepared. Next, the prepared liquid is diluted 10 times (volume basis) with pure water to prepare a sample solution. Then, when the particle size of the resin in the sample solution is measured by dynamic light scattering, if particles having a particle size are not measured, the resin can be determined to be water-soluble. On the other hand, if particles having a particle size are measured, the resin can be determined to be "resin particles" (i.e., "water-dispersible resin"). The measurement conditions at this time can be, for example, as follows. [Measurement conditions] SetZero: 30 seconds Number of measurements: 3 Measurement time: 180 seconds

[0055] As the particle size distribution measuring device, a particle size analyzer using a dynamic light scattering method (for example, the product name "UPA-EX150" manufactured by Nikkiso Co., Ltd.) can be used. Of course, the particle size distribution measuring device and the measurement conditions to be used are not limited to those described above.

[0056] [Aqueous medium] The ink is an aqueous ink containing at least water as an aqueous medium. The ink may contain water or an aqueous medium that is a mixed solvent of water and a water-soluble organic solvent. As the water, deionized water (ion-exchanged water) is preferably used. The content (mass%) of water in the ink is preferably 50.00 mass% or more and 95.00 mass% or less based on the total mass of the ink. As the water-soluble organic solvent, any of those usable for inkjet inks, such as alcohols, glycols, (poly)alkylene glycols, nitrogen-containing compounds, and sulfur-containing compounds, can be used. The content (mass%) of the water-soluble organic solvent in the ink is preferably 3.00 mass% or more and 50.00 mass% or less based on the total mass of the ink.

[0057] [Surfactants] The ink preferably further contains a surfactant. Examples of the surfactant include anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, and other surfactants. Of these, it is preferable to use a nonionic surfactant.

[0058] The content (mass %) of the surfactant in the ink is preferably from 0.10% to 5.00% by mass, more preferably from 0.10% to 2.00% by mass, and particularly preferably from 0.10% to 1.00% by mass, based on the total mass of the ink.

[0059] [Other ingredients] In addition to the above components, the ink may contain, as necessary, water-soluble organic compounds that are solid at room temperature, such as polyhydric alcohols such as trimethylolpropane and trimethylolethane, urea and its derivatives, and sugars and its derivatives. Furthermore, the ink may contain, as necessary, various additives, such as antifoaming agents, pH adjusters, viscosity adjusters, rust inhibitors, preservatives, antifungal agents, antioxidants, and reduction inhibitors.

[0060] [Ink properties] The ink is a water-based ink applied to the inkjet method. Therefore, from the viewpoint of reliability, it is preferable to appropriately control the physical property values. Specifically, the static surface tension of the ink at 25°C is preferably 28 mN / m or more and 45 mN / m or less. In addition, the viscosity of the ink at 25°C is preferably 1.0 mPa·s or more and 5.0 mPa·s or less, and more preferably 1.0 mPa·s or more and 3.0 mPa·s or less. The pH of the ink at 25°C is preferably 5.0 or more and 9.5 or less. As described above, when using a protective tape having an adhesive layer formed of an acrylic adhesive containing a metal chelate-based crosslinking agent, the pH of the ink is preferably 8.6 or more, and more preferably 8.9 or more and 9.3 or less. EXAMPLES

[0061] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples without departing from the gist of the invention. "Parts" and "%" used to describe the amounts of components are based on mass unless otherwise specified.

[0062] <Preparation of pigment dispersion> (Pigment dispersion 1) A solution of 5.0 g of concentrated hydrochloric acid in 5.5 g of water was cooled to 5°C, and 1.5 g of 4-amino-1,2-benzenedicarboxylic acid was added in this state. The container containing this solution was placed in an ice bath, and while stirring to maintain the temperature of the solution below 10°C, a solution obtained by dissolving 1.8 g of sodium nitrite in 9.0 g of water at 5°C was added. After stirring for 15 minutes, the specific surface area was 250 m 26.0 g of carbon black with a DBP oil absorption of 140 mL / 100 g was added under stirring. Stirring was continued for another 15 minutes to obtain a slurry. The obtained slurry was filtered through filter paper (product name "Standard Filter Paper No. 2", manufactured by Advantec), and the particles were thoroughly washed with water and dried in an oven at 110°C. Thereafter, sodium ions were replaced with potassium ions by ion exchange to obtain a self-dispersing pigment in which -C6H3-(COOK)2 groups were bonded to the pigment particle surface. An appropriate amount of water was added to adjust the pigment content, and pigment dispersion 1 with a pigment content of 15.00% was obtained.

[0063] (Pigment dispersion 2) A styrene-acrylic acid copolymer with an acid value of 90 mgKOH / g and a weight average molecular weight of 10,000 was neutralized with a 10% aqueous solution of potassium hydroxide. Carbon black (specific surface area 220 m 2 A mixture was obtained by mixing 10.0 parts of styrene-acrylic acid copolymer (solid content) (100 mL / 100 g, DBP oil absorption 100 mL / 100 g), 2.0 parts of neutralized styrene-acrylic acid copolymer (solid content), and 88.0 parts of ion-exchanged water. The mixture obtained was dispersed using a sand grinder for 1 hour, and then centrifuged to remove coarse particles. The mixture was then filtered under pressure using a microfilter (manufactured by Fujifilm) with a pore size of 3.0 μm to obtain pigment dispersion 2 in which carbon black was dispersed in water by the resin. The pigment content in pigment dispersion 2 was 15.00%, and the resin dispersant content was 3.00%.

[0064] (Pigment dispersion 3) A styrene-acrylic acid copolymer with an acid value of 120 mgKOH / g and a weight average molecular weight of 10,000 was neutralized with a 10% potassium hydroxide aqueous solution. 10.0 parts of CI Pigment Blue 15:3, 3.0 parts of the neutralized styrene-acrylic acid copolymer (solid content), and 85.0 parts of ion-exchanged water were mixed to obtain a mixture. The mixture obtained was dispersed for 1 hour using a sand grinder, and then centrifuged to remove coarse particles. Furthermore, the mixture was filtered under pressure using a microfilter (manufactured by Fujifilm) with a pore size of 3.0 μm to obtain pigment dispersion 3 in which CI Pigment Blue 15:3 was dispersed in water by the resin. The pigment content in pigment dispersion 3 was 15.00%, and the resin dispersant content was 3.00%.

[0065] (Pigment Dispersion 4) Pigment Dispersion 4 was obtained in the same manner as Pigment Dispersion 3 described above, except that CI Pigment Red 122 was used instead of CI Pigment Blue 15:3. The pigment content in Pigment Dispersion 4 was 15.00%, and the resin dispersant content was 3.00%.

[0066] (Pigment Dispersion 5) Pigment Dispersion 5 was obtained in the same manner as Pigment Dispersion 3 described above, except that CI Pigment Yellow 74 was used instead of CI Pigment Blue 15:3. The pigment content in Pigment Dispersion 5 was 15.00%, and the resin dispersant content was 3.00%.

[0067] <Preparation of dye aqueous solution> CI Direct Blue 199 was dissolved in ion-exchanged water, and then acid was added to precipitate the dye. The precipitated dye was filtered and separated to obtain a wet cake of the free acid dye. The obtained wet cake was added to ion-exchanged water, and an aqueous solution containing an equimolar amount of sodium hydroxide to the anionic groups of the dye was added to neutralize all the anionic groups and dissolve the dye. An appropriate amount of ion-exchanged water was added to obtain an aqueous dye solution with a dye content of 15.00%.

[0068] <Preparation of Resin> (Acrylic Resin 1) Acrylic resin 1 was synthesized by copolymerizing 81.0 parts of styrene and 19.0 parts of acrylic acid according to a conventional method. The carboxylic acid group was neutralized with potassium hydroxide in an amount equimolar to the acid value of acrylic resin 1, and an appropriate amount of pure water was added to obtain a liquid containing acrylic resin 1 with a resin content of 20.00%. The acid value of acrylic resin 1 was 148 mgKOH / g, and the weight average molecular weight measured by gel permeation chromatography was 10,000.

[0069] (urethane resin) A four-neck flask equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, and a reflux tube was prepared. 41.5 parts of isophorone diisocyanate, 40.6 parts of polypropylene glycol, 15.7 parts of dimethylolpropionic acid, and 300.0 parts of methyl ethyl ketone were placed in this four-neck flask. Then, the mixture was reacted at 80°C for 6 hours under a nitrogen gas atmosphere. Next, 3.6 parts of polyamine were added and reacted at 80°C to obtain a reaction liquid. After the reaction liquid obtained was cooled to 40°C, ion-exchanged water was added, and an aqueous potassium hydroxide solution was added while stirring at high speed with a homomixer to obtain a liquid. Methyl ethyl ketone was distilled off from the liquid obtained by heating and reducing the pressure, and a liquid containing a urethane resin with a urethane resin (solid content) content of 20.00% was obtained.

[0070] (Acrylic Resin 2) A solution was prepared by mixing 79.4 parts of ion-exchanged water and 0.2 parts of potassium persulfate. An emulsion was prepared by mixing 16.7 parts of butyl methacrylate, 0.4 parts of methacrylic acid, 3.0 parts of ethylene glycol methyl diacrylate, and 0.3 parts of "Aqualon KH-05" (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). The prepared emulsion was dropped into the above solution over 1 hour under a nitrogen atmosphere, and a polymerization reaction was carried out while stirring at 80°C, and then stirred for 2 hours. After cooling to room temperature, ion-exchanged water and an aqueous potassium hydroxide solution were added to adjust the pH to 8.5, and a liquid containing acrylic resin 2 with a resin particle content of 20.00% was obtained.

[0071] <Ink Preparation> Each component (unit: %) shown in the upper part of Tables 1-1 and 1-2 was mixed, thoroughly stirred, and then pressure filtered through a microfilter (manufactured by Fujifilm) with a pore size of 3.0 μm to prepare each ink. In Tables 1-1 and 1-2, the numerical value attached to polyethylene glycol indicates the number average molecular weight, and "Acetylenol E100" is the trade name of an acetylene glycol-based nonionic surfactant (manufactured by Kawaken Fine Chemicals). The pigment content and resin content in the obtained ink, as well as the pH of the ink at 25°C, are shown in the lower part of Tables 1-1 and 1-2. The pH of the ink was adjusted by adding a 1 mol / L aqueous solution of acetic acid or an 8 mol / L aqueous solution of potassium hydroxide. The amount of the aqueous solution of acetic acid or the aqueous solution of potassium hydroxide used for pH adjustment was included in the pure water content.

[0072] TIFF2025024685000002.tif133170

[0073] TIFF2025024685000003.tif132170

[0074] <Configuration of the recording unit (ink cartridge)> A recording unit (ink cartridge) was prepared in which a recording head that ejects ink by applying thermal energy to an ink storage unit 10 without using a heat sink was directly attached to the ink storage unit 10 as shown in FIG. 3. The recording element substrate constituting the recording head has an ejection port array in which 384 ejection ports are arranged at an array density of 600 dpi. The mass of an ink droplet ejected from one ejection port is 5.5 ng. The recording head used had an ejection port surface made of epoxy resin that was treated to be water repellent with a water repellent agent. The water repellent agent was a resin obtained by hardening a condensation product of a hydrolyzable silane compound having a fluoroalkyl group (a compound having a fluoromethyl group and a methoxy group) and a hydrolyzable silane compound having a cationic polymerizable group (a compound having an epoxy group and an ethoxy group). A protective tape having an adhesive layer was attached to the ejection port surface of the recording head to manufacture a recording unit. The characteristics of the obtained recording unit are shown in Table 2.

[0075] TIFF2025024685000004.tif62170

[0076] <Evaluation> As device 1, we prepared a product name "PIXUS TS5130S" (manufactured by Canon), which is an inkjet recording device in which when the ink contained inside the ink container (ink cartridge) is consumed, it is replaced with a new ink container filled with ink. As device 2, we prepared a product name "G3370" (manufactured by Canon), which is an inkjet recording device in which the ink container (sub-tank) on the carriage and the ink container (main tank) placed inside the device are connected by a tube through which the ink flows. These inkjet recording devices were equipped with a blade-shaped wiper (contact pressure: 1.2 kgf / mm) made of urethane resin that wipes the ejection port surface of the recording head. 2 ) was incorporated. The penetration depth of the wiper in the first wiping step was 1.3 mm, and the penetration depth of the wiper in the second and third wiping steps was 1.0 mm. In Comparative Example 4, an inkjet recording device equipped with two wipers with penetration depths of 1.3 mm and 1.0 mm was used. The time difference between the passage of the two wipers was 0.03 seconds. Immediately after peeling off the protective tape from the recording unit of the type shown in Tables 3-1 and 3-2, the recording unit was set on the carriage of the above recording device, and the cleaning sequence described later was performed, and then each item described later was evaluated.

[0077] First, the first cleaning sequence was performed under the conditions shown in Tables 3-1 and 3-2. Details of the conditions are shown below. In the first cleaning sequence, the first wiping process was performed in which the nozzle face was wiped with the bent wiper, and then the height of the carriage was changed and the second wiping process was performed in which the nozzle face was wiped with the edge of the wiper. In Examples 5 and 41, the recording unit was set in the recording device immediately after peeling off the protective tape, and five nozzle check patterns for the "PIXUS TS5130S" or "G3370" were recorded, and then the first cleaning sequence was performed. Condition 1: 1st wiping process 2 times → 2nd wiping process 2 times Condition 2: 1x 1st wiping process → 1x 2nd wiping process Condition 3: 1st wiping step 1 time → 2nd wiping step 2 times Condition 4: 1st wiping process 2 times → 2nd wiping process 1 time Condition 5: 1st wiping process 1 time → 2nd wiping process 1 time → 1st wiping process 1 time → 2nd wiping process 1 time Condition 6: First wiping process 4 times Condition 7: Second wiping process 4 times Condition 8: 1 time for 2 wiper pairs

[0078] Next, a third wiping step was performed as the second cleaning sequence, in which the edge (or bottom) of the wiper was used to wipe the ejection port surface under the conditions shown in Tables 3-1 and 3-2. In the examples shown as "Yes" in the "Recording head heating" column in Tables 3-1 and 3-2, the temperature of the ink in the recording head was heated to 60°C when the second cleaning sequence was performed.

[0079] In this embodiment, the printing duty of a solid image printed under conditions in which two ink droplets, each with a mass of 5.5 ng, are applied to a unit area of ​​1 / 600 inch x 1 / 600 inch, is defined as 100%. The evaluation conditions are shown in Tables 3-1 and 3-2. In the present invention, in the evaluation criteria for each item shown below, "AA", "A", and "B" were defined as acceptable levels, and "C" was defined as an unacceptable level. The evaluation results are shown in Table 4.

[0080] TIFF2025024685000005.tif179170

[0081] TIFF2025024685000006.tif173170

[0082] (Discharge at the beginning of initial use) Each ink was concentrated by evaporating 10%. The prepared ink was placed in a fluorine-treated container and stored at 70°C for one month. The stored concentrated ink was used for the evaluation in order to evaluate the state of ejection irregularity under more severe conditions. The stored ink was poured into the ink storage section of the recording unit, then set in the recording device, and the ejection port surface was cleaned under the conditions shown in Tables 3-1 and 3-2. After that, the nozzle check patterns of the "PIXUS TS5130S" or "G3370" were recorded on glossy paper, coated paper, and plain paper, respectively. The glossy paper used was "Photo Paper Glossy Gold GL-101" (Canon). The coated paper used was "High-quality Dedicated Paper HR-101" (Canon). The plain paper used was "PPC Paper CS-680" (Canon). The three types of nozzle check patterns were visually observed, and ejection irregularity at the start of initial use was evaluated according to the following evaluation criteria. AA: No distortion occurred in the nozzle check pattern for any of the three types of recording media. A: Creases occurred on glossy paper, but no creasing occurred on coated paper or plain paper. B: Curling occurred on glossy paper and coated paper, but not on plain paper. C: Wrinkling occurred on all three types of recording media.

[0083] (Discharge irregularities after long-term use) After the evaluation of "irregular ejection at the beginning of initial use" was performed, a nozzle check pattern was recorded on 15,000 sheets of recording medium (product name "High-quality dedicated paper HR-101", manufactured by Canon) for the "PIXUS TS5130S" or "G3370". The nozzle check pattern recorded on the 15,000th sheet was visually observed, and irregular ejection after long-term use was evaluated according to the following evaluation criteria. A: No irregular ejection occurred in the nozzle check pattern recorded on the 15,000th recording medium. C: Irregular ejection occurred in the nozzle check pattern recorded on the 15,000th recording medium.

[0084] TIFF2025024685000007.tif197170

[0085] Although Examples 36 and 39 were rated A for "irregular discharge at the start of initial use," irregular discharge was relatively suppressed compared to other Rank A examples.

Claims

1. an ink jet recording device including: an aqueous ink containing a pigment and a resin; an ink storage section for storing the aqueous ink; a recording head having an ejection port surface formed with ejection ports for ejecting the aqueous ink supplied from the ink storage section and incorporated in the ink storage section; and a wiping means for wiping the ejection port surface, the ejection port surface having been treated to be water repellent; An inkjet recording method comprising a step of applying the water-based ink ejected from the ejection orifice to a recording medium to record an image, a protective tape having an adhesive layer formed of an adhesive, the adhesive layer being peeled off when the recording head is used, is attached to the ejection port surface of the recording head; The method further includes a first cleaning sequence including a first wiping step and a second wiping step that are performed successively to wipe the ejection port surface using a single blade-shaped wiper, the first wiping step is a step of bending the wiper to wipe the ejection port surface with a bottom portion of the wiper, an ink jet recording method, characterized in that the second wiping step is a step of wiping the ejection port surface with an edge portion of the wiper;

2. The ink jet recording method according to claim 1 , wherein the first cleaning sequence is performed immediately after the protective tape is peeled off.

3. The ink jet recording method according to claim 1 , wherein the first wiping step is carried out only in the first cleaning sequence.

4. Further, a second cleaning sequence is executed after the first cleaning sequence, 2. The ink jet recording method according to claim 1, wherein the second cleaning sequence includes a third wiping step of wiping the ejection port surface with an edge portion of the wiper while heating the recording head.

5. 2. The ink jet recording method according to claim 1, wherein an interval between the end of the first wiping step and the start of the second wiping step is 5 seconds or more and 15 seconds or less.

6. 6. The ink jet recording method according to claim 1, wherein the wiper has a thickness of 0.5 mm or more and 1.5 mm or less.

7. The inkjet recording method according to claim 1 , wherein the first wiping step and the second wiping step are each performed two or more times.

8. 6. The ink jet recording method according to claim 1, wherein a speed at which the nozzle surface is wiped with the wiper is 100 mm / s or more and 150 mm / s or less.

9. 6. The inkjet recording method according to claim 1, wherein a penetration amount of the wiper in the first wiping step is 1.0 mm or more and 1.8 mm or less, and a penetration amount of the wiper in the second wiping step is 0.3 mm or more and 1.0 mm or less.

10. 6. The ink-jet recording method according to claim 1, wherein the pigment is carbon black.

11. 6. The inkjet recording method according to claim 1, wherein a content (mass %) of the pigment in the aqueous ink is from 0.50 mass % to 10.00 mass % based on the total mass of the ink.

12. 6. The inkjet recording method according to claim 1, wherein the content (mass %) of the resin in the water-based ink is 0.10 mass % or more and 20.00 mass % or less based on the total mass of the ink.

13. 6. The ink jet recording method according to claim 1, wherein the pressure-sensitive adhesive is a silicone-based pressure-sensitive adhesive or an acrylic pressure-sensitive adhesive.

14. 6. The ink jet recording method according to claim 1, wherein the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive.

15. the acrylic pressure-sensitive adhesive contains a metal chelate crosslinking agent, The inkjet recording method according to claim 14, wherein the pH of the water-based ink at 25° C. is 8.6 or more.

16. The inkjet recording method according to claim 11, wherein the pH of the water-based ink at 25° C. is from 8.9 to 9.

3.

17. 6. The ink jet recording method according to claim 1, wherein the ink containing unit is replaced with another ink containing unit after the water-based ink contained therein is consumed.

18. 6. The inkjet recording method according to claim 1, further comprising: a second ink containing section having a larger capacity than the ink containing section; and a tube through which the water-based ink circulates between the second ink containing section and the ink containing section.

19. an ink jet recording device including: an aqueous ink containing a pigment and a resin; an ink storage section for storing the aqueous ink; a recording head having an ejection port surface formed with ejection ports for ejecting the aqueous ink supplied from the ink storage section and incorporated in the ink storage section; and a wiping means for wiping the ejection port surface, the ejection port surface having been treated to be water repellent; an inkjet recording apparatus for use in an inkjet recording method having a step of applying the water-based ink discharged from the discharge port to a recording medium to record an image, a protective tape having an adhesive layer formed of an adhesive, the adhesive layer being peeled off when the recording head is used, is attached to the ejection port surface of the recording head; the inkjet recording method further includes a first cleaning sequence including a first wiping step and a second wiping step that are performed successively to wipe the ejection port surface with a single blade-shaped wiper, the first wiping step is a step of bending the wiper to wipe the ejection port surface with a bottom portion of the wiper, an ink jet recording apparatus, wherein the second wiping step is a step of wiping the ejection port surface with an edge portion of the wiper;

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