JP2014079932A - Maintenance liquid, ink supply system and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a maintenance liquid having excellent dissolution and storage stabilities and improving initial chargeability of an ink and stability of continuous printing, an ink supply system with excellent initial chargeability of an ink and stability of continuous printing and an ink jet recorder equipped with the ink supply system.SOLUTION: A maintenance liquid contains an alkylene oxide adduct of an acetylene glycol having a 12C or higher principal chain, an acetylene glycol having a 10C or higher principal chain and a polyoxyalkylene alkyl ether.

Description

  The present invention relates to a maintenance liquid, an ink supply system, and an ink jet recording apparatus.

  2. Description of the Related Art Conventionally, in a printing method using an ink jet recording method, ink is supplied to a print head, and ink droplets are ejected from the print head and fly to adhere to a recording medium such as paper. When ejecting ink, it is known that ejection failure occurs due to bubbles generated in the ink. Thus, various techniques for removing bubbles and stably ejecting ink by degassing ink using a deaeration device or the like have been proposed (see, for example, Patent Documents 1 and 2).

  Further, as a method for supplying ink to the print head, a method is disclosed in which ink is supplied from the ink outlet portion of the ink tank to the print head attached to the printer via a tube (see, for example, Patent Documents 3 and 4). ).

JP 2010-23362 A JP 2011-42104 A Japanese National Patent Publication No. 11-504874 JP 2003-127427 A

  However, even if the ink is deaerated as disclosed in Patent Documents 1 and 2, minute bubbles are likely to be mixed due to gas-liquid exchange accompanying ink filling or ink consumption, and the ink is kept in the deaerated state. However, initial filling property and continuous printing stability are insufficient.

  Also, in the ink supply methods disclosed in Patent Documents 3 and 4, minute bubbles are easily mixed by gas-liquid exchange accompanying ink filling or ink consumption, and air is introduced into the ink tank. In such a case, if bubbles flow out from the ink tank together with the ink and are carried to the print head, the initial filling property and the continuous printing stability are deteriorated.

  The present invention has been made in view of the above problems, and has an object to provide a maintenance liquid that is excellent in dissolution stability and storage stability, and improves the initial filling property and continuous printing stability of ink. To do. Another object of the present invention is to provide an ink supply system and an ink jet recording apparatus including the ink supply system, which are excellent in initial filling property and continuous printing stability.

  The present inventors diligently studied to solve the above problems. As a result, separately from ink, by using a predetermined maintenance liquid that is pre-filled in at least one of the ink container and the ink flow path before ink filling, it is possible to perform gas-liquid exchange during ink filling or ink consumption. It has been found that generation of minute bubbles can be prevented, and that initial filling properties and continuous printing stability are improved, and the present invention has been completed.

That is, the present invention is as follows.
[1]
An alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain;
Acetylene glycol having 10 or more carbon atoms in the main chain;
Including polyoxyalkylene alkyl ethers,
Maintenance liquid.
[2]
The maintenance liquid according to the above item [1], wherein the polyoxyalkylene alkyl ether has an HLB value of 12 to 16.
[3]
The alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain includes an ethylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain, as described in [1] or [2] above. Maintenance fluid.
[4]
The content of the polyoxyalkylene alkyl ether, and the total content of acetylene glycol having an alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain and 10 or more carbon atoms in the main chain, The maintenance liquid according to any one of [1] to [3], wherein the mass ratio is in the range of 0.10: 1.0 to 0.50: 1.0.
[5]
The maintenance liquid according to any one of [1] to [4] above, wherein the alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain has an HLB value of 8 to 15.
[6]
The maintenance liquid according to any one of [1] to [5] above, wherein the acetylene glycol having 10 or more carbon atoms in the main chain has an HLB value of 4 or less.
[7]
The maintenance liquid according to any one of [1] to [6], further including an organic solvent.
[8]
An ink storage container including a liquid storage chamber having an air inlet, wherein air is generated from the air inlet into the liquid stored in the liquid storage chamber, thereby generating bubbles in the liquid;
A print head having a nozzle for discharging the liquid;
An ink supply path for connecting the ink storage container and the print head and supplying the liquid from the ink storage container to the print head;
The maintenance liquid according to any one of [1] to [7] above is provided as the liquid in at least one of the liquid storage chamber and the ink supply path.
Ink supply system.
[9]
The ink supply system according to [8], wherein a filter is further provided in the ink supply path, and an average pore diameter of the filter is equal to or less than a nozzle diameter of the nozzle.
[10]
The ink supply system according to [8] or [9], wherein a plurality of the filters are provided in the ink supply path.
[11]
The ink supply system according to any one of [8] to [10], wherein a material of the filter is resin.
[12]
The ink supply system according to any one of [8] to [11] above,
An ink jet recording apparatus that ejects ink supplied from the ink container to the print head from the print head toward a recording medium.

1 is a block diagram illustrating an overall configuration of a printer including an ink supply system. It is the schematic which shows the cross section of the printer provided with the ink supply system. It is the schematic for demonstrating the principle of the ink supply from an ink container to a head.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. However, the present invention is not limited to this, and various modifications can be made without departing from the gist thereof. Is possible.

[Maintenance liquid]
The maintenance liquid of this embodiment contains an alkylene oxide adduct of acetylene glycol having a main chain having 12 or more carbon atoms, an acetylene glycol having 10 or more carbon atoms in the main chain, and a polyoxyalkylene alkyl ether. It is a waste.
Hereinafter, each component contained in the maintenance liquid of the present embodiment or that may be contained will be described in detail.

  The “maintenance liquid” in the present embodiment is a liquid that is prefilled in at least one of the ink container and the ink flow path before ink filling for the purpose of defoaming effect at the time of ink filling, and is different from ink. Is. The maintenance liquid having the above composition can prevent the generation of minute bubbles during ink filling. As a result, filling and ejection defects in the print head are improved, and initial filling properties and continuous printing stability are improved. Further, by using the maintenance liquid, it is not necessary to contain a large amount of a surfactant in the ink, and it is possible to avoid instability of ink characteristics and restrictions on the ink composition.

  Here, the “ink channel” means a channel for distributing ink in the ink jet recording apparatus. As the ink flow path, for example, an ink supply path for supplying ink from an ink container that stores ink to the ink jet recording head, or a flow path for distributing ink to the nozzle opening in the ink jet recording head Is mentioned.

  The location and amount of the maintenance liquid to be filled are not particularly limited, and at least a part of the ink container or the ink flow path may be filled with the maintenance liquid. In order to improve the initial filling property of the ink, it is preferable to fill the maintenance liquid in the ink container on the upstream side before filling the ink. Accordingly, it is possible to efficiently remove bubbles generated in the ink container during ink filling and bubbles in the ink flow path, thereby improving the initial filling property of the ink.

  Further, when the image recording using the ink jet recording apparatus is not performed for a long period of time or when ejection failure occurs, at least one of the ink storage container and the ink flow path can be replaced with the maintenance liquid. . The replacement with the maintenance liquid is performed by causing the maintenance liquid to flow into at least one of the ink storage container or the ink flow path filled with ink and using at least one of the ink in the ink storage container or the ink flow path as the maintenance liquid. It can be done by replacing. At this time, prior to the inflow of the maintenance liquid, at least one of the ink in the ink container or the ink flow path may be discharged out of the system.

  On the other hand, when resuming image recording using the ink jet recording apparatus, ink is allowed to flow into at least one of the ink container filled with the maintenance liquid or the ink flow path, and the maintenance liquid is discharged from the nozzle opening. By discharging, the maintenance liquid may be replaced with ink. At this time, prior to the inflow of ink, at least one of the maintenance liquid in the ink container or the ink flow path may be discharged from the nozzle opening.

  Further, in order to fill at least one of the ink container and the ink flow path with the ink or the maintenance liquid, the ink and the maintenance liquid may be filled so as to be replaced by a normal cleaning operation. In addition, the nozzle opening surface of the recording head is sealed with a cap, connected to the cap with a suction pump, and a negative pressure is generated in the cap by the suction pump, whereby ink or maintenance liquid is circulated in the ink flow path. It may be filled with.

[Alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain]
The maintenance liquid of this embodiment contains an alkylene oxide adduct of acetylene glycol having a main chain having 12 or more carbon atoms (hereinafter also simply referred to as “AO adduct”). The “main chain” in the present specification means the main chain of acetylene glycol determined based on the IUPAC nomenclature.

  The AO adduct having 12 or more carbons in the main chain imparts wettability to the maintenance liquid with respect to foreign substances that can contribute to the generation of bubbles in the polymer member such as rubber and plastic that constitute the ink flow path and the ink. . Therefore, by using the maintenance liquid containing the AO adduct, it is possible to suppress the generated bubbles from remaining during ink filling. Thereby, the initial filling property of the ink is improved, and it is possible to prevent both the growth of the remaining bubbles and the dot omission due to the separation of the bubbles adhering to the flow path surface, thereby improving the continuous printing stability.

  The AO adduct is excellent in solubility in the maintenance liquid, and improves the solubility in the maintenance liquid of acetylene glycol having 10 or more carbon atoms in the main chain described later. Thereby, if it is the maintenance liquid of this embodiment, both solubility and defoaming property are achieved.

  The HLB (Hydrophile-Lipophile Balance) value of the AO adduct is preferably 8-15, more preferably 10-13. By setting it as the said preferable range, it exists in the tendency for the wettability with respect to the foreign material which may be a cause of bubble generation to become further excellent. In addition, the HLB value in this specification is defined by the Griffin method.

Although it does not specifically limit as an AO adduct, Specifically, the compound represented by following formula (1) is mentioned.
In the above formula (1), R ¹ , R ^{1 ′} , R ² , and R ^{2 ′} each independently represent a linear or branched alkyl group having 1 to 5 carbon atoms, and represented by acetylene glycol Carbon number of the main chain is 12 or more, and —OR ³ and —OR ^{3 ′} each independently represent —OH or —O (C _m H _2m O) _n H. However, the case where both -OR ³ and -OR ^{3 '} are -OH is excluded. Here, m shows the integer of 1-5. Also, n is a value including a decimal fraction of 0.5 to 25, representing the average degree of polymerization of the added alkylene oxide _{(C m H 2m} O).

The total number of added moles of alkylene oxide units (total of R ³ and R ^{3 ′} ) is preferably 2 to 40 moles. By being the said preferable range, a static and dynamic surface tension can be made small and it exists in the tendency for initial stage filling property to become more favorable.

  Although it does not specifically limit as an AO adduct, Specifically, the ethoxylate of 2,5,8,11-tetramethyl-6-dodecine-5,8-diol, 5,8-dimethyl-6-dodecin- Examples include ethoxylated products of 5,8-diol, orphine EXP4300 (trade name, carbon number 12, ethylene oxide adduct made by Nissin Chemical Industry CO., Ltd.).

  The maintenance liquid of this embodiment preferably contains an ethylene oxide adduct or a propylene oxide adduct as the AO adduct, and more preferably contains an ethylene oxide adduct. By including an ethylene oxide adduct, it is easy to stably exist in a maintenance liquid containing water, but it has better wettability to foreign matters that can contribute to the generation of bubbles. Tend to be better.

  AO adducts may be used alone or in combination of two or more. The content of the AO adduct is preferably 0.05 to 0.30% by mass with respect to the total mass (100% by mass) of the maintenance liquid.

[Acetylene glycol having 10 or more carbon atoms in the main chain]
The maintenance liquid of this embodiment contains acetylene glycol having 10 or more carbon atoms in the main chain. Acetylene glycol having 10 or more carbon atoms in the main chain is excellent in defoaming properties, and by containing it in the maintenance liquid, bubbles generated during the introduction of ink can be effectively defoamed. Thereby, initial filling property and continuous printing stability are improved.

  The HLB value of acetylene glycol having 10 or more carbon atoms in the main chain is preferably 7 or less, more preferably 5 or less, and even more preferably 4 or less. The lower limit is preferably 3 or more. By being in the above range, the antifoaming property tends to be more excellent.

The acetylene glycol having 10 or more carbon atoms in the main chain is not particularly limited, and specific examples include acetylene glycol represented by the following formula (2).
In the above formula (2), R ⁴ , R ^{4 ′} , R ⁵ , and R ^{5 ′} each independently represent a linear or branched alkyl group having 1 to 5 carbon atoms, represented by acetylene glycol The main chain has 10 or more carbon atoms.

  The acetylene glycol having 10 or more carbon atoms in the main chain is not particularly limited. Specifically, 2,5,8,11-tetramethyl-6-dodecin-5,8-diol (manufactured by Air Products; Surfynol DF110D), 5,8-dimethyl-6-dodecin-5,8-diol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol (manufactured by Air Products; Surfynol 104PG50) ) And 4,7-dimethyl-5-decyne-4,7-diol.

  Acetylene glycol having 10 or more carbon atoms in the main chain may be used alone or in combination of two or more. The content of acetylene glycol having 10 or more carbon atoms in the main chain is preferably, for example, 0.05 to 0.30% by mass with respect to the total mass (100% by mass) of the maintenance liquid. More preferably, it is 0.20 mass%. By setting it as the said preferable range, it exists in the tendency which is excellent by continuous printing stability.

  The total content of acetylene glycol having 10 or more carbon atoms in the main chain and the above-mentioned AO adduct (hereinafter collectively referred to as “acetylene glycol-based compound”) is preferably 0.1 to 0.6% by mass, 0.1-0.5 mass% is more preferable. By setting it as the said preferable range, the solubility to water becomes more favorable and it exists in the tendency which can prevent more effectively generating an aggregate when these acetylene glycol is mix | blended.

  The mass ratio of the content of acetylene glycol having 10 or more carbon atoms in the main chain and the content of the AO adduct described above is preferably 0.5: 1 to 2.5: 1. More preferably, the ratio is 5: 1 to 2.0: 1, and more preferably 0.5: 1 to 1.5: 1. By setting it as the said preferable range, it exists in the tendency which is excellent by initial stage filling property and continuous printing stability.

[Polyoxyalkylene alkyl ether]
The maintenance liquid of this embodiment contains polyoxyalkylene alkyl ether. The polyoxyalkylene alkyl ether acts as a solubilizer that dissolves or disperses the above-mentioned AO adduct and acetylene glycol having 10 or more carbon atoms in the main chain in the maintenance liquid. Any of the above acetylene glycols has a low dynamic surface tension, and polyoxyalkylene alkyl ethers can be said to be solubilizers that do not affect the low dynamic surface tension.

  11-16 are preferable, as for the HLB value of polyoxyalkylene alkyl ether, 12-16 are more preferable, and 12-15 are more preferable. By setting it as the said preferable range, it exists in the tendency which initial stage filling property and continuous printing stability are more excellent.

Although it does not specifically limit as a polyoxyalkylene alkyl ether, Specifically, the compound represented by following formula (3) is mentioned.
R ⁶ O (C ₂ H ₄ O) _w (C ₃ H ₆ O) _x (C ₂ H ₄ O) _y (C ₃ H ₆ O) _z H (3)
In said formula (3), R < ⁶ > represents a C1-C20 alkyl group, w is a value of 1-20, x, y, and z are the values of 0 or 1-20 independently of each other. There are w + x + y + z = 5-30. In the above formula (3), R ⁶ is preferably an alkyl group having 5 to 15 carbon atoms, and more preferably an alkyl group having 10 to 15 carbon atoms. Moreover, 5-30 are preferable and, as for w + x + y + z, 5-25 are more preferable. By setting it as the said preferable range, it exists in the tendency which is excellent by storage stability and continuous printing stability.

Although it does not specifically limit as polyoxyalkylene alkyl ether, Specifically,
_{C 12 H 25 O (C 2} H 4 O) 6 (C 3 H 6 O) 2 (C 2 H 4 O) 6 (C 3 H 6 O) 8 H,
_{C 13 H 27 O (C 2} H 4 O) 6 (C 3 H 6 O) 2 (C 2 H 4 O) 6 (C 3 H 6 O) 8 H,
_{C 12 H 25 O (C 2} H 4 O) w (C 3 H 6 O) x (C 2 H 4 O) y (C 3 H 6 O) z H
(Where w + y = 15, x + z = 4),
_{C 13 H 27 O (C 2} H 4 O) w (C 3 H 6 O) x (C 2 H 4 O) y (C 3 H 6 O) z H
(Where w + y = 15, x + z = 4),
_{C 12 H 25 O (C 2} H 4 O) 8 (C 3 H 6 O) 2 (C 2 H 4 O) 6 H,
_{C 13 H 27 O (C 2} H 4 O) 8 (C 3 H 6 O) 2 (C 2 H 4 O) 6 H,
_{C 12 H 25 O (C 2} H 4 O) 12 (C 3 H 6 O) 2 (C 2 H 4 O) 12 H,
_{C 13 H 27 O (C 2} H 4 O) 12 (C 3 H 6 O) 2 (C 2 H 4 O) 12 H,
_{CH 3 (CH 2) 9 (} CH 3) CHO (C 2 H 4 O) 7 (C 3 H 6 O) 4.5 H,
_{CH 3 (CH 2) 11 (} CH 3) CHO (C 2 H 4 O) 7 (C 3 H 6 O) 4.5 H,
_{CH 3 (CH 2) 9 (} CH 3) CHO (C 2 H 4 O) 5 (C 3 H 6 O) 3.5 H,
_{CH 3 (CH 2) 11 (} CH 3) CHO (C 2 H 4 O) 5 (C 3 H 6 O) 3.5 H,
_{C 14 H 29 O (C 2} H 4 O) 14 (C 3 H 6 O) 2 H,
C ₁₁ H ₂₃ O (C ₂ H ₄ O) ₈ H,
C ₁₀ H ₂₁ O (C ₂ H ₄ O) ₁₁ H, and C ₁₂ H ₂₅ O (C ₂ H ₄ O) ₁₅ H.

Examples of commercially available polyoxyalkylene alkyl ether is not particularly limited, specifically, Noigen ^{_{DL-0415 (R 6 O (}} C 2 H 4 O) W (C 3 H 6 O) x (C 2 H 4 O) _y (C ₃ H ₆ O) _z H, “R ⁶ ”: alkyl having 12 and 13 carbon atoms, w + y = 15, x + z = 4, HLB value 15.0), Neugen ET-116B (R ⁶ O ( C ₂ H ₄ O) ₇ (C ₃ H ₆ O) _4.5 H, “R ⁶ ”: alkyl having 12 and 14 carbon atoms, HLB value 12.0), Neugen ET-106A (R ⁶ O (C ₂ H ₄ O) ₅ (C ₃ H ₆ O) _3.5 H, “R ⁶ ”: alkyl having 12 and 14 carbon atoms, HLB value 10.9), Neugen DH-0300 (R ⁶ O (C ₂ H ₄ O) ₂ H, “R ⁶ ”: C 14 alkyl, HLB value 4.0 ), Noigen ^{_{YX-400 (R 6 O (}} C 2 H 4 O) 40 H, ^{"R 6":} alkyl of 12 carbon atoms, HLB value 18.1), Noigen _{EA-160 (C 9 H 19} C 6 H ₄ O (C ₂ H ₄ O) _16.8 H, HLB value 15.4) (above, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), Emulgen 1108 (trade name, manufactured by Kao Corporation, R ⁶ O (C ₂ H ₄ O) ₈ H, “R ⁶ ”: alkyl having 11 carbon atoms, HLB value 13.4).

  A polyoxyalkylene alkyl ether may be used individually by 1 type, and may be used in combination of 2 or more type. The content of the polyoxyalkylene alkyl ether is preferably 0.01 to 0.50% by mass and preferably 0.05 to 0.30% by mass with respect to the total mass (100% by mass) of the maintenance liquid. Is more preferable. By setting it as the said preferable range, it exists in the tendency which is excellent by storage stability and continuous printing stability.

  The mass ratio (the former: the latter) of the polyoxyalkylene alkyl ether content (the former) and the AO adduct content (the latter) is 0.10: 1.0 to 1.0: 1. 0 is preferable, and 0.30: 1.0 to 0.70: 1.0 is more preferable. By setting it as the said preferable range, the solubility of an AO adduct improves more and it exists in the tendency for water solubility to become more favorable. Thereby, generation | occurrence | production of the aggregate at the time of mix | blending is suppressed more, and it exists in the tendency which is excellent by dissolution stability and storage stability.

  The mass ratio of the content of polyoxyalkylene alkyl ether and the total content of acetylene glycol having 10 or more carbon atoms in the AO adduct and main chain is 0.10: 1.0 to 0.50. Is preferably in the range of 1.0, and more preferably in the range of 0.10: 1.0 to 0.40: 1.0. By setting it as the said preferable range, it exists in the tendency for an acetylene glycol type compound to solubilize and for water solubility to become more favorable. Thereby, generation | occurrence | production of the aggregate at the time of mix | blending a polyoxyalkylene alkyl ether and an acetylene glycol type compound is suppressed more, and it exists in the tendency which is excellent by dissolution stability and storage stability.

[Surfactants other than the above]
The ink in the present embodiment may contain a surfactant other than those described above. Although it does not specifically limit as surfactant, Specifically, Olfin E1010 (carbon number 10 of a principal chain, the addition mole number 10 of ethylene oxide, 2,4,7,9-tetramethyl-5-decyne-4) , 7-diol ethoxylate; manufactured by Nissin Chemical Industry Co., Ltd.), orphine E1004 (carbon number of main chain, number of moles of added ethylene oxide 4,2,4,7,9-tetramethyl-5-decyne-4 7-diol ethoxylate; manufactured by Nissin Chemical Industry Co., Ltd., Olphine 82W (main chain carbon number 8, no addition of ethylene oxide, 3,6-dimethyl-4-octyne-3,6-diol; Nissin Chemical Manufactured by Kogyo Co., Ltd.).

〔water〕
The maintenance liquid in this embodiment may contain water. Examples of water include water from which ionic impurities have been removed as much as possible, such as pure water such as ion exchange water, ultrafiltration water, reverse osmosis water, and distilled water, and ultrapure water. In addition, when water sterilized by ultraviolet irradiation or addition of hydrogen peroxide is used, generation of mold and bacteria can be prevented when the maintenance liquid is stored for a long time, and storage stability tends to be further improved. . The water content is not particularly limited and can be appropriately determined as necessary.

〔Organic solvent〕
It is preferable that the maintenance liquid of this embodiment further contains an organic solvent. By including an organic solvent, the initial filling property tends to be superior. Among the organic solvents, volatile water-soluble organic solvents are more preferable. The organic solvent is not particularly limited, and specifically, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,2 -Pentanediol, 1,2-hexanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol mono-n-propyl ether, ethylene glycol mono-iso-propyl ether, diethylene glycol Mono-iso-propyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-t-butyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monobutyl Ether, diethylene glycol mono-t-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-t-butyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-iso-propyl ether, propylene glycol mono- n-butyl ether, dipropylene glycol mono-n-butyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-iso-propyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol ethyl methyl ether, diethylene glycol Butylme Ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, tripropylene glycol dimethyl ether, methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, 2-butanol, alcohols or glycols such as tert-butanol, iso-butanol, n-pentanol, 2-pentanol, 3-pentanol, and tert-pentanol; N, N-dimethylformamide, N, N-dimethylacetamide, 2-pyrrolidone, N-methyl-2-pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, Examples include sulfolane and 1,1,3,3-tetramethylurea.

  An organic solvent may be used individually by 1 type, and may be used in combination of 2 or more type. The content of the organic solvent is not particularly limited, and can be appropriately determined as necessary. For example, when at least one of initial filling property, storage stability, and continuous printing stability is excellent, from 1,2-hexanediol, triethylene glycol monobutyl ether, and dipropylene glycol monopropyl ether It is preferable to use one or more selected from the group consisting of:

  In addition, it is preferable that content of the sum total of water and the organic solvent shall be 60-98 mass% with respect to the total mass (100 mass%) of a maintenance liquid. By setting it as the said preferable range, it exists in the tendency for storage stability and continuous printing stability to be more excellent.

[Other ingredients]
In addition to the above materials, the maintenance liquid of the present embodiment may further contain pH adjusters such as triethanolamine and tripropanolamine, preservatives / fungicides, rust preventives, chelating agents, and the like.

[Manufacturing method of maintenance liquid]
The maintenance liquid of the present embodiment can be obtained by mixing the above-described materials (components) in an arbitrary order, performing filtration or the like as necessary, and removing impurities. Here, the temperature at the time of mixing the above-mentioned AO adduct and the acetylene glycol having 10 or more carbon atoms in the main chain and the polyoxyalkylene alkyl ether is preferably 10 to 30 ° C.

  As a method for mixing each material, a method in which materials are sequentially added to a container equipped with a stirring device such as a mechanical stirrer or a magnetic stirrer and stirred and mixed is preferably used. As a filtration method, for example, centrifugal filtration or filter filtration can be performed as necessary.

[Ink supply system]
The ink supply system of the present embodiment includes a liquid storage chamber having an air inlet, and air is introduced into the liquid stored in the liquid storage chamber from the air inlet so that bubbles are generated in the liquid. An ink container (ink tank) that is generated, a print head having a nozzle for discharging the liquid, an ink that connects the ink container and the print head, and supplies the liquid from the ink container to the print head And the maintenance liquid as the liquid in at least one of the liquid storage chamber and the ink supply path.

  In the ink supply system of the present embodiment, the maintenance liquid stored in the ink storage container suppresses the generation of bubbles when the ink is filled, and the maintenance liquid in the ink supply path passes through the ink supply path through the print head (hereinafter referred to as the ink supply system). It is also simply referred to as “head”.) Since the bubbles can be removed before reaching the head), the initial ink filling property and the continuous printing stability are excellent. Specifically, the maintenance liquid has excellent wettability, and acts as a so-called priming water when ink is filled. In addition, maintenance liquid with excellent wettability takes in air bubbles adhering to members such as the ink container and ink supply path, and when the maintenance liquid that has taken in air bubbles passes through the filter, the filter captures the air bubbles taken in. Thus, bubbles can be removed from the maintenance liquid.

[Inkjet recording device]
The ink jet recording apparatus of the present embodiment (hereinafter also simply referred to as “recording apparatus” or “printer”) includes the ink supply system, and the ink supplied from the ink container to the print head is recorded from the print head. The recording is performed by discharging toward the medium. Hereinafter, the recording apparatus and the ink supply system of this embodiment will be described in detail.

  The recording apparatus provided with the ink supply system can be classified into several types according to the method of the recording apparatus and the ink supply system. Examples of the type of recording apparatus include a line printer and a serial printer. The line printer includes a line head having a length corresponding to the width of the recording medium, and the head is fixed without moving (almost) and printing is performed in one pass (single pass). . On the other hand, a serial printer normally performs printing in two or more passes (multi-pass) while the head reciprocates (shuttle movement) in a direction orthogonal to the conveyance direction of the recording medium.

  In the recording apparatus, as an ink supply type, an off-carriage type in which an ink container and a carriage head are connected by an ink supply path such as a tube may be used.

  Hereinafter, an off-carriage type serial printer will be exemplified, and an ink supply system and a recording apparatus including the ink supply system will be described with reference to the drawings. In each drawing used for the following description, the scale is appropriately changed for each component in order to make each component (member) large enough to be recognized on the drawing. The present embodiment is not limited only to the ratio of the number, shape, and size of the components and the relative positional relationship of the components described in these drawings.

[1. Configuration of recording apparatus]
FIG. 1 is a block diagram illustrating a configuration of a printer 1 including an ink supply system. FIG. 2 is a schematic diagram illustrating a cross section of the printer 1 including the ink supply system.

  The printer 1 according to the present embodiment is an apparatus that forms an image on a recording surface of a recording medium by ejecting ink toward the recording medium such as paper. Here, the printer 1 of this embodiment can form an image using inks of various colors. For example, cyan, magenta, yellow, and black (hereinafter, “C”, “M”, “ Y ”and“ Bk ”) may be used to form an image, or a white ink may be used to form a base that provides excellent concealment to a recording medium. Can be mentioned. Furthermore, a clear ink may be applied to these CMYBk and white inks, thereby increasing glossiness.

  The printer 1 includes a transport unit 10, a carriage unit 20, a head unit 30, an ink storage unit 40, a detector group 50, and a controller 60. The printer 1 that has received print data from the computer 110, which is an external device, controls each unit (the transport unit 10, the carriage unit 20, the head unit 30, and the ink containing unit 40) by the controller 60. The controller 60 controls each unit based on the print data received from the computer 110 and prints an image on a recording medium. The situation in the printer 1 is monitored by the detector group 50, and the detector group 50 outputs the detection result to the controller 60. The controller 60 controls each unit based on the detection result output from the detector group 50.

  The transport unit 10 is for transporting a recording medium such as paper in a predetermined direction (hereinafter referred to as “transport direction”). The transport unit 10 includes a paper feed roller 11, a transport motor (not shown), a transport roller 13, a platen 14, and a paper discharge roller 15. The paper feed roller 11 is a roller for feeding the recording medium inserted into the paper insertion slot into the printer 1. The transport roller 13 is a roller that transports the recording medium fed by the paper feed roller 11 to a printable area, and is driven by a transport motor. The platen 14 supports a recording medium being printed. The paper discharge roller 15 is a roller for discharging the recording medium to the outside of the printer 1 and is provided on the downstream side in the transport direction with respect to the printable area.

  The carriage unit 20 is a moving mechanism that moves the head 31 in a direction crossing the transport direction (hereinafter referred to as “moving direction”). The carriage unit 20 includes a carriage 21, a carriage motor (not shown), and a sub tank 22 as necessary. The carriage 21 includes a sub tank 22 and a head 31, and is connected to a carriage motor (not shown) via a timing belt (not shown). The carriage 21 is reciprocated along the guide shaft 24 by a carriage motor while being supported by a guide shaft 24 that intersects a conveyance direction described later. The guide shaft 24 supports the carriage 21 so as to be capable of reciprocating in the axial direction of the guide shaft 24. The sub-tank 22 is for suppressing ink pressure fluctuation in the head 31 that may be caused by the reciprocating motion of the carriage 21.

  Although not shown, the carriage unit 20 may include a plurality of sub tanks 22 and store inks of different colors. On the contrary, the carriage unit 20 does not have to include the sub tank 22, and in this case, the ink container 41 and the head 31 are connected via the ink supply path 42. The sub tank 22 will be described in more detail with reference to FIG.

  The head unit 30 is for ejecting ink from the head 31 to the recording medium. The head unit 30 includes a plurality of heads 31 having nozzles. The head 31 is provided on the carriage 21 and moves together with the carriage 21. By ejecting ink while the head 31 moves, an image is formed on the recording surface of the recording medium. Although not shown, for example, the plurality of heads 31 may eject ink corresponding to the colors stored in the plurality of sub-tanks 22.

  The ink storage unit 40 stores ink and supplies the stored liquid to the head 31 via an ink supply path. The ink storage unit 40 includes an ink storage container 41, an ink supply path 42, and a filter 43. The ink container 41 is placed at a different location from the carriage 21. The ink container 41 and the head 31 (carriage 21) are connected by an ink supply path 42. The filter 43 is provided in the ink supply path 42.

  The ink storage container 41 includes a liquid storage chamber 340 having an air inlet 352, and bubbles are generated in the liquid by introducing air from the air inlet 352 into the liquid stored in the liquid storage chamber 340. To do. Further, the ink container 41 has a structure in which the atmosphere and the liquid can come into contact with each other. It should be noted that, when air is introduced from the air introduction port 352, the liquid and the air introduction port 352 are in contact with each other in a state where the liquid is contained in the liquid accommodation chamber 340 so that bubbles are generated in the liquid. You may do it.

  Here, “liquid” is a concept including ink and the above-described maintenance liquid, and includes at least one of them. In this embodiment, the maintenance liquid is provided as a liquid in at least one of the liquid storage chamber and the ink supply path, so that both initial filling properties and continuous printing stability are excellent. When using the ink supply system and the ink jet recording apparatus, the ink storage container 41 or the ink supply path 42 is replaced so that the maintenance liquid filled in at least one of the ink storage container 41 or the ink supply path 42 is replaced. It is possible to supply (fill, refill) ink to at least one of them. Furthermore, in addition to the already filled ink, it is possible to supply (fill, refill) the ink, or replace the already filled ink with the maintenance liquid again.

  Although not shown, the ink supply system and the recording apparatus can have a plurality of ink containers 41. The plurality of ink storage containers 41 may store ink corresponding to the color of ink stored in the plurality of sub tanks 22. Each ink container 41 is preferably capable of confirming the ink level from the outside from a predetermined portion. Note that the ink container 41 is placed at a different location from the carriage, so that there is less space restriction. Therefore, a larger amount of ink than the sub tank 22 can be accommodated.

  The ink supply path 42 is an ink flow path for connecting the ink container 41 and the head 31 and supplying ink in the ink container 41 to the head 31. The ink supply path 42 can connect the ink storage container 41 that can store ink of each color and the sub tank 22 that can store ink of the corresponding color. The ink supply path 42 can be formed of a flexible member such as synthetic rubber, and can be a hose or a tube. When the liquid is discharged from the head 31 and the liquid in the sub tank 22 is consumed, the liquid in the ink container 41 is supplied to the sub tank 22 through the ink supply path 42. Thereby, the printer 1 can continue printing continuously without interruption operation for a long time. The ink container 41 and the ink supply path 42 will be described in more detail with reference to FIG.

  The filter 43 is provided in the flow path of the ink supply path 42. When the liquid flowing through the ink supply path 42 includes bubbles, the filter 43 can prevent the bubbles from flowing into the head 31 by capturing the bubbles. Thereby, both the liquid filling in the head 31 and the ink ejection from the head 31 are excellent, and both the initial filling property and the continuous printing stability are excellent.

  The installation location of the filter 43 is not particularly limited as long as it is in the ink supply path 42, and at least one can be provided. For example, the filter 43 may be provided in the vicinity of the outlet of the ink container 41 (liquid outlet 306) or in the vicinity of the inlet to the head. In the tank, bubbles tend to be generated when ink is filled or when ink is consumed. By suppressing the bubbles from flowing into the flow path, the initial filling property and the continuous printing stability can be further improved. A plurality of filters 43 may be provided, but in order to maintain a good liquid flow, the number of filters provided in one flow path is preferably about 1 to 3, and more preferably 1 to 2.

  The average hole diameter of the filter 43 is preferably equal to or smaller than the nozzle diameter of the nozzles of the head 31 in order to prevent nozzle omission due to air bubbles being ejected from the nozzles of the head 31. The said nozzle diameter is about 10-30 micrometers normally, and about 10-20 micrometers is more preferable. Here, the “average pore diameter of the filter” in the present specification means that the bead beads having the same diameter as the average pore diameter can be removed by 50%. In addition, “nozzle diameter” in the present specification means the diameter of the thinnest part of the nozzle.

  Although it does not specifically limit as a material of the filter 43, Specifically, resin (nonwoven fabric, maps), such as stainless steel (mesh) and a polypropylene, is mentioned. Among them, the material of the filter 43 is preferably a resin because impurities such as foreign matters that may be generated in the flow path are easily captured due to the resin or rubber member forming the tank, the tube, or the like. By capturing the impurities and bubbles in the liquid with the filter 43, it is possible to prevent the impurities from adhering to the bubbles or being carried alone to the nozzles of the head 31 to cause nozzle omission. That is, by making the material of the filter 43 preferable as described above, the initial filling property and the continuous printing stability tend to be more excellent.

  The detector group 50 includes a linear encoder (not shown), a rotary encoder (not shown), a paper detection sensor 53, an optical sensor 54, and the like. The linear encoder detects the position of the carriage 21 in the moving direction. The rotary encoder detects the amount of rotation of the transport roller 13. The paper detection sensor 53 detects the position of the leading end of a recording medium such as paper being fed. The optical sensor 54 is attached to the carriage 21 and detects the presence or absence of a recording medium by a light emitting unit and a light receiving unit. The optical sensor 54 can detect the position of the end of the recording medium while being moved by the carriage 21 to detect the width of the recording medium. The optical sensor 54 can also detect the front end (end on the downstream side in the transport direction) and the rear end (end on the upstream side in the transport direction) of the recording medium depending on the situation.

  The controller 60 is a control unit (control unit) for controlling the printer 1. The controller 60 includes an interface unit 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface unit 61 transmits and receives data between the computer 110 that is an external device and the printer 1. The CPU 62 is an arithmetic processing unit for controlling the entire printer 1. The memory 63 is for securing an area for storing a program of the CPU 62, a work area, and the like, and includes storage elements such as a RAM and an EEPROM. The CPU 62 controls each unit via the unit control circuit 64 in accordance with a program stored in the memory 63.

  When recording, the controller 60 controls the dot forming operation for ejecting ink from the head 31 and the transporting operation for transporting the recording medium in the transporting direction alternately to form an image composed of a plurality of dots. Can be printed on a recording medium. As described above, the ink jet recording apparatus of the present embodiment provided with the above ink supply system forms an image in a region facing the head 31 of the recording medium.

[2. Operation of the recording device)
The operation of the recording apparatus of the present embodiment includes a recording operation for forming an image by attaching ink to a recording medium and a conveying operation for conveying the recording medium. The recording apparatus of this embodiment performs recording by alternately performing a recording operation and a transport operation. During recording, the recording medium is not conveyed but is held by the platen 14 located in the recording area. The recording operation is not particularly limited. Specifically, the ink supply operation supplies ink from the ink container 41 to the head 31, and the purpose of supplying ink stably from the ink container 41 to the head 31. Thus, an air introduction operation for introducing the atmosphere (air) into the ink container 41 and an ejection operation for ejecting ink from the head 31 toward the recording medium can be included. By such an operation of the recording apparatus, a desired image can be formed in a region facing the head 31 in the recording medium.

  The ink supply operation includes an operation of further filling the ink container 41 with the reduced amount of ink supplied. The operation of the recording apparatus according to the present embodiment can be rephrased as an ink jet recording method using an ink supply system, and each operation included in the operation of the above-described recording apparatus can be rephrased as a “process”. it can.

  Hereinafter, a recording medium used for the recording operation in the present embodiment will be described, and then an example of the recording operation will be described.

(2-1. Recording medium)
The recording medium is not particularly limited, and specific examples include an ink-absorbing recording medium. The ink-absorbing recording medium is not particularly limited, and specifically, plain paper such as electrophotographic paper having high water-based ink permeability; an ink-absorbing layer composed of silica particles or alumina particles, or polyvinyl Inkjet paper with an ink absorbing layer composed of a hydrophilic polymer such as alcohol (PVA) or polyvinylpyrrolidone (PVP); art paper or coated paper used for general offset printing with relatively low water-based ink permeability , And cast paper.

(2-2. Maintenance operation)
In the maintenance operation in the present embodiment, the maintenance liquid is filled in advance in at least one of the ink container and the ink flow path before ink filling. Thereafter, by filling the ink supply system filled with the maintenance liquid with ink, generation of minute bubbles at the time of ink filling can be prevented, and the generated bubbles can be removed by a filter. As a result, filling and ejection defects in the print head are improved, and initial filling properties and continuous printing stability are improved.

(2-3. Ink supply operation)
The recording operation in the present embodiment includes an ink supply operation. The ink supply operation supplies ink from the ink container 41 to the head 31, and the ink supply system of the above embodiment can be used. The ink supply operation will be described in detail later.

(2-4. Air introduction operation)
The recording operation in the present embodiment further includes an air introduction operation. The air introduction operation assists the ink supply operation, and the ink supply system of the embodiment can be used. For example, as described above, in a recording operation using an ink supply system that includes an ink containing container having an air introduction flow path for introducing air and generating bubbles in ink, the air introduction operation is performed. Done. The air introduction operation is to introduce air (air) into the ink container 41 for the purpose of stably supplying ink from the ink container 41 to the head 31. The air introduction operation will be described in detail later.

(2-5. Discharge operation)
The recording operation in the present embodiment includes an ejection operation. The ejection operation is an inkjet recording method in which an ink droplet is ejected onto a recording medium to form an image. As a discharge method, a conventionally known method can be used. In particular, a method of ejecting droplets from the nozzles using the vibration of the piezoelectric element (a recording method using a head that forms ink droplets by mechanical deformation of the electrostrictive element), or a bubble in the head using a heating element. By using a method in which ink is ejected from the nozzles, better recording can be performed. Various discharge conditions such as the discharge temperature and time and the viscosity of the discharged ink are not particularly limited.

  Hereinafter, the ink supply operation and the air introduction operation will be described in detail among the recording operations in the present embodiment.

  FIG. 3 is a schematic diagram for explaining the principle of ink supply from the ink container 41 which is an example of the ink container 41 to the head 31. The ink supply method shown in FIG. 3 is based on the principle of the Marriott bottle, in short, and the head 31 and the ink container 41 are connected via the sub tank 22 and the ink supply path 42 provided in the carriage 21. In this way, by generating a negative pressure inside the sub tank 22, the ink is sucked and supplied from the ink container 41 to the head 31. FIG. 3 schematically shows mainly the inside of the ink storage container 41, the ink supply path 42, and the sub tank 22.

  The printer 1 is installed on a predetermined horizontal plane sf. The liquid outlet 306 of the ink container 41 and the liquid receiver 202 of the sub tank 22 are connected via the ink supply path 42.

  The sub tank 22 is formed of a synthetic resin such as polystyrene or polyethylene. The sub tank 22 includes an ink storage chamber 204, an ink flow path 208, and a filter 206. An ink supply needle 21 a of the carriage 21 is inserted into the ink flow path 208. The filter 206 prevents inflow of impurities into the head 31 by capturing impurities when impurities such as foreign matter are mixed in the ink flowing through the ink flow path 206. The ink in the ink storage chamber 204 is supplied to the head 31 through the ink flow path 208 and the ink supply needle 21 a by suction from the head 31. The ink supplied to the head 31 is ejected and attached to the recording medium through the nozzles to form an image (the above-described ejection operation).

  Here, even when the sub tank 22 is provided between the ink storage container 41 and the head 31 as in the present embodiment, the ink supply path 42 connects the ink storage container 41 and the head 31. An ink supply path 42 also exists in the sub tank 22. Therefore, in the above case, both the filter 43 and the filter 206 correspond to filters provided in the ink supply path 42.

  FIG. 3 is a preferred embodiment in which a filter 206 is provided in the flow path in the sub tank 22. As a result, the collected bubbles accumulate in the space above the sub-tank 22, so that the flow path is less likely to be blocked by the collection of bubbles. In addition, the aspect provided with both the filter 43 and the filter 206 like FIG. 3 may be sufficient, and the aspect provided only with the filter 206 may be sufficient.

  Moreover, as another preferable one aspect | mode, the bubble 43 produced just before the head 31 (upstream side) can be effectively collected by providing the filter 43 in front of the head 31 (upstream side). For example, a mode in which a filter is provided inside the ink supply needle 21a to which the sub tank 22 is attached can be mentioned. According to this mode, it is possible to effectively collect bubbles generated when the cartridge is attached or detached. Note that a plurality of filters can also be provided in an embodiment in which a filter is provided inside the ink supply needle.

  The ink container 41 supplies ink to the head 31 of the printer 1 using the principle of Marriott bottle. The outer surface of the ink container 41 includes a first wall 370C1, a second wall (upper wall) 370C2, and a bottom wall 370C3. The ink container 41 has an air introduction channel and an ink channel inside thereof. The air introduction channel is a channel for introducing air from the atmosphere opening port 317 to the liquid storage chamber 340 through the atmosphere introduction port 318 via an atmosphere channel (not shown). The ink flow path liquid injection path 304 is a flow path for filling ink from the ink flow path liquid injection path 304 to the liquid storage chamber 340.

  First, the air introduction channel is a channel used in the above-described air introduction operation. The air introduction flow path includes an atmosphere opening port 317 that opens toward the outside (atmosphere), an air storage chamber 330 that has the air introduction port 318 as one end and the air chamber side opening 351 as the other end, and an air chamber side opening 351. And a liquid chamber communication path 350 having the air inlet 352 as the other end. The atmosphere opening port 317 communicates with the atmosphere, the air storage chamber 330 opens at the atmosphere introduction port 318 at one end, and the atmosphere opening port 317 and the atmosphere introduction port 318 communicate with each other via a channel (not shown). That is, the air accommodating chamber 330 communicates with the outside (atmosphere). In the liquid chamber communication path 350, an air chamber side opening 351, which is one end, opens at the air accommodation chamber 330, and an air introduction port 352, which is the other end, opens at the liquid accommodation chamber 340. In other words, the air storage chamber 330 communicates with the liquid storage chamber 340. The liquid chamber communication path 350 preferably has a flow passage cross-sectional area small enough to form a meniscus (liquid level cross-linking).

  As described above, in the air introduction flow path, the air introduction port 352 that is one end opens in the liquid storage chamber 340, and the atmosphere opening port 317 that is the other end opens toward the outside. That is, when the ink storage container 41 to be described later is used, a liquid level that is in direct contact with the atmosphere is formed in the liquid chamber communication path 350 (specifically, in the vicinity of the air introduction port 352), and the liquid is contained from the air introduction port 352. Air (bubbles G) is introduced into the liquid storage chamber 340 by introducing air (bubbles) into the ink in the chamber 340. Accordingly, as described later, ink can be stably supplied from the ink container 41 to the head 31. In other words, the air introduction operation described so far is performed for the purpose of stabilizing the ink supply operation described later.

  On the other hand, the ink flow path is used in the ink supply operation described above. These ink supply operations are performed as the ink storage amount of the ink container 41 is reduced due to the ejection operation from the head 31, and are stably performed by the air introduction operation.

  Here, the ink container 41 has a use state and an injection state. The “used state” is a state of the ink container 41 installed on the horizontal plane when supplying ink to the head 31 of the printer 1. In other words, in the state of use, the liquid injection path 304 is open in the horizontal direction (here, the opening is closed by the plug member 302). FIG. 3 shows the ink container 41 in the use state. In use, the liquid storage chamber 340 and the air storage chamber 330 are arranged in the horizontal direction. Further, in the use state, the air inlet 352 is positioned below the liquid level of the liquid stored in the liquid storage chamber 340. On the other hand, the “injection state” is a state of the ink container 41 installed on the horizontal surface when ink is injected into the ink container 41. In other words, in the injection state, the liquid injection path 304 is open upward. In the injection state, the liquid storage chamber 340 and the air storage chamber 330 are arranged in the vertical direction. Further, in the injection state, the air introduction port 352 has a liquid amount when the liquid level of the liquid stored in the liquid storage chamber 340 in the use state is on the straight line LM1 (“first state display line LM1”). When stored in the storage chamber 340, it is located above the liquid level of the liquid stored in the liquid storage chamber 340.

  In the above-described injection state, the user may stop the ink filling when the ink liquid level reaches the vicinity of the straight line LM2 (“second state display line LM2”) that is horizontal in the injection state. In this way, after the liquid storage chamber 340 is injected with ink from the liquid injection path 304, the liquid injection path 304 is sealed with the plug member 302. Further, the ink in the liquid storage chamber 340 is sucked from the head 31 so that the liquid storage chamber 340 is maintained at a negative pressure.

  In the use state described above, the air introduction port 352 is located below the first state display line LM1. In FIG. 3, the air introduction port 352 is formed in the bottom wall 370 </ b> C <b> 3 located on the lower side of the container main body 45 defining the liquid storage chamber 340 with the liquid storage chamber 340 in between in use. Thus, even if the ink in the liquid storage chamber 340 is consumed and the liquid level in the liquid storage chamber 340 is lowered, the liquid level (atmospheric contact liquid level) LA in contact with the atmosphere is long (the ink level is in the first state). It is maintained at a constant height over a period of time until it reaches the display line LM1. Further, the air inlet 352 is disposed at a position lower than the head 31 in the use state. Thereby, the water head difference d1 occurs. In the state of use, the water head difference d1 in a state where the air contact liquid level LA that is a meniscus is formed in the vicinity of the air inlet 352 of the liquid chamber communication path 350 is also referred to as “steady-state water head difference d1” below.

  As the ink in the ink storage chamber 204 is sucked by the head 31, the ink storage chamber 204 becomes equal to or higher than a predetermined negative pressure. When the ink storage chamber 204 reaches a predetermined negative pressure or higher, the ink in the liquid storage chamber 340 is supplied to the ink storage chamber 204 via the ink supply path 42. That is, the ink storage chamber 204 is automatically further supplied (supplemented) with the amount of ink that has flowed out of the head 31 from the liquid storage chamber 340. In other words, the water head difference generated by the vertical height difference between the air containing chamber 330 in the ink containing container 41, that is, the air contact liquid surface (ink liquid surface) LA in contact with the air, and the nozzle surface of the head 31. Ink is supplied from the liquid storage chamber 340 to the ink storage chamber 204 because the suction force (negative pressure) from the head 31 side becomes somewhat larger than the suction force generated by d1.

  When the ink in the liquid storage chamber 340 is consumed, the air in the air storage chamber 330 is introduced as bubbles G into the liquid storage chamber 340 via the liquid chamber communication path 350. That is, in the liquid storage chamber 340 of the ink storage container 41, the air introduced through the air introduction flow path comes into contact with the stored ink. As a result, the ink level LF in the liquid storage chamber 340 is lowered. On the other hand, since the height of the atmospheric contact liquid level LA in contact with the atmosphere is maintained constant, the water head difference d1 is maintained constant. That is, the ink can be stably supplied from the ink container 41 to the head 31 from the viewpoint of the amount of ink by the predetermined suction force of the head 31.

  As described above, although the ink container 41 can stably supply ink, a part of the bubbles G flows out to the liquid outlet 306 together with the ink and is carried to the head 31 to cause problems such as missing dots. Problems arise. More specifically, as shown in the figure surrounded by the upper left square in FIG. 3, when the bubble G is generated in the ink from the air inlet 352, the bubble G is split, and the bubble Ga having a normally assumed size and In addition, there may be a case where micro bubbles Gb that are considerably smaller than the size of the air inlet 352 are generated. In the ink container 41, the microbubbles Gb have a diameter of about several tens of μm, for example. The buoyancy of the microbubbles Gb is small (for example, 0.1 mm / s) and is particularly susceptible to the ink flow in the liquid storage chamber 340. When performing continuous printing with high duty using the printer 1, the microbubbles Gb flow along the ink flow and flow into the head 31 side of the printer 1 through the liquid outlet 306, causing problems such as missing dots. It becomes easy to do.

  Therefore, the filter 43 is provided in the flow path of the ink supply path 42 and the composition of the ink is set to a predetermined value so that the filter 43 captures the micro bubbles Gb contained in the ink, and the head 31 of the micro bubbles Gb. Prevent inflow into As a result, the ink supply system of the present embodiment and the recording apparatus of the present embodiment including the ink supply system are excellent in ejection and excellent in continuous printing stability.

  Further, as described above, if the ink container 41 has a structure in which the air introduced from the outside comes into contact with the ink, the ink positively adsorbs bubbles attached to members such as the ink container 41 and the ink supply path 42. In some cases, undesirable bubbles such as microbubbles Gb may be included. However, when the ink that has taken in the bubbles passes through the filter 43 of the ink supply path 42, the taken-in bubbles can be captured by the filter 43, and the bubbles can be removed from the ink. Therefore, ink that does not contain bubbles is supplied to the head 31, and problems such as missing dots can be prevented. As a result, the ink supply system of the present embodiment and the recording apparatus of the present embodiment including the ink supply system are excellent in ejection and excellent in continuous printing stability.

[3. (Modification)
The ink supply system according to the above embodiment and the recording apparatus according to the present embodiment including the ink supply system are not limited to the specific examples described so far, and may be implemented in various forms without departing from the scope of the invention. It is possible. For example, the following modifications are mentioned.

  In the recording apparatus of this embodiment, by generating a negative pressure inside the sub tank 22, the ink is not sucked and supplied from the ink container 41 to the head 31, but is pressurized by the pump from the ink container 41 to the head 31. May be provided. As described above, the ink container 41 and the head 31 may be connected via the ink supply path 42 without providing the sub tank 22.

  Thus, according to the embodiment and the present embodiment, it is possible to provide an ink supply system and an ink jet recording apparatus including the ink supply system, which are excellent in initial filling property and continuous printing stability.

〔ink〕
The ink used in the ink supply system and the ink jet recording apparatus including the ink supply system is not particularly limited, and a conventionally known ink can be used. Hereinafter, although the components contained in the ink are listed, the components contained in the ink are not limited to these.

[Surfactant]
The ink can include a surfactant. Such a surfactant is not particularly limited. Specifically, the above-described AO adduct, acetylene glycol having 10 or more carbon atoms in the main chain, polyoxyalkylene alkyl ether, and other interfaces than those described above. An activator is mentioned. These surfactants may be used alone or in combination of two or more. The content of the surfactant is not particularly limited and can be appropriately determined as necessary.

  By using the maintenance liquid of the present invention, it is possible to prevent the generation of minute bubbles due to gas-liquid exchange accompanying ink filling or ink consumption, thereby improving initial filling ability and continuous printing stability. For this reason, it is possible to reduce the amount of the surfactant contained in order to give the ink a defoaming effect. This alleviates various problems such as compatibility between the solubility of the surfactant in the ink and the defoaming property, a decrease in the dissolution stability of the ink, and a decrease in storage stability. In addition, the problem of destabilizing ink properties, difficulty in obtaining the desired defoaming property, and the problem of easily shortening the life of filtration filters and modules due to the inclusion of a large amount of surfactant in the ink is alleviated. The In addition, the restriction on the ink composition of designing an ink having high defoaming properties is eased, and the ink characteristics do not deteriorate.

[Colorant]
The ink in the present embodiment preferably further includes a colorant. The colorant is not particularly limited, and both dyes and pigments can be used. Colors exhibited by the colorant include, for example, yellow, magenta, cyan, black, white, green, orange, red, blue, light yellow, light magenta, light yellow, light black, light green, light orange, light red, and Light blue is mentioned.

  As the pigment, an inorganic pigment or an organic pigment can be used. Examples of inorganic pigments include, but are not limited to, titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow, carbon black, bitumen, and metal powder. It is done.

  Although it does not specifically limit as said organic pigment, Specifically, an azo pigment, a polycyclic pigment, a nitro pigment, a nitroso pigment, and aniline black are mentioned. Among these, at least one of an azo pigment and a polycyclic pigment is preferable. Among these, azo pigments are not particularly limited, and specific examples include azo lakes, insoluble azo pigments, condensed azo pigments, and chelate azo pigments. Although it does not specifically limit as a polycyclic pigment, Specifically, a phthalocyanine pigment, a perylene pigment, a perinone pigment, an anthraquinone pigment, a quinacridone pigment, a dioxazine pigment, an indigo pigment, a thioindigo pigment, an isoindolinone pigment, a quinofullerone pigment, an azomethine Pigments and rhodamine B lake pigments.

  The dispersion form of the pigment when using a pigment as the colorant is not particularly limited. As the pigment, it is preferable to use a pigment that has undergone surface treatment and a pigment that uses a dispersant. The above surface-treated pigment can be dispersed in an aqueous solvent by directly or indirectly bonding a hydrophilic group (carboxyl group, sulfonic acid group, etc.) to the pigment surface by physical treatment or chemical treatment. (Hereinafter, also referred to as “self-dispersing pigment”). Examples of the pigment using the above dispersant include those obtained by dispersing the pigment with a surfactant or a resin (hereinafter, also referred to as “polymer dispersed pigment”). Here, any known substances can be used as the surfactant and the resin. In addition, the “polymer dispersed pigment” includes a pigment coated with a resin. The pigment coated with the resin can be obtained by an acid precipitation method, a phase inversion emulsification method, a miniemulsion polymerization method, or the like.

  As the dye, an oil-soluble dye or a water-soluble dye can be used. Among these, the oil-soluble dye is not particularly limited, and specific examples include dyes classified as disperse dyes in the color index. Although it does not specifically limit as water-soluble dye, Specifically, each dye classified into an acid dye, a direct dye, a basic dye, a reactive dye, and a food dye in a color index is mentioned.

  Although it does not specifically limit as said acidic dye and food dye, Specifically, C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142; C.I. I. Acid Red 1, 8, 13, 14, 18, 26, 27, 35, 37, 42, 52, 82, 87, 89, 92, 97, 106, 111, 114, 115, 134, 186, 249, 254 289; I. Acid Blue 9, 29, 45, 92, 249; I. Acid Black 1, 2, 7, 24, 26, 94; I. Food Yellow 3, 4; I. Food red 7, 9, 14; I. Food black 1, 2 etc. are mentioned.

  Although it does not specifically limit as said direct dye, Specifically, C.I. I. Direct yellow 1, 12, 24, 26, 33, 44, 50, 86, 120, 132, 142, 144; I. Direct Red 1, 4, 9, 13, 17, 20, 28, 31, 39, 80, 81, 83, 89, 225, 227; I. Direct orange 26, 29, 62, 102; I. Direct Blue 1, 2, 6, 15, 22, 25, 71, 76, 79, 86, 87, 90, 98, 163, 165, 199, 202; I. Direct black 19, 22, 32, 38, 51, 56, 71, 74, 75, 77, 154, 168, 171 etc. are mentioned.

  Although it does not specifically limit as said basic dye, Specifically, C.I. I. Basic yellow 1, 2, 11, 13, 14, 15, 19, 21, 23, 24, 25, 28, 29, 32, 36, 40, 41, 45, 49, 51, 53, 63, 64, 65, 67, 70, 73, 77, 87, 91; I. Basic Red 2, 12, 13, 14, 15, 18, 22, 23, 24, 27, 29, 35, 36, 38, 39, 46, 49, 51, 52, 54, 59, 68, 69, 70, 73, 78, 82, 102, 104, 109, 112; I. Basic blue 1, 3, 5, 7, 9, 21, 22, 26, 35, 41, 45, 47, 54, 62, 65, 66, 67, 69, 75, 77, 78, 89, 92, 93, 105, 117, 120, 122, 124, 129, 137, 141, 147, 155; I. Basic black 2, 8 etc. are mentioned.

  Although it does not specifically limit as said reactive dye, Specifically, C.I. I. Reactive black 3, 4, 7, 11, 12, 17; I. Reactive Yellow 1, 5, 11, 13, 14, 20, 21, 22, 25, 40, 47, 51, 55, 65, 67; I. Reactive Red 1, 14, 17, 25, 26, 32, 37, 44, 46, 55, 60, 66, 74, 79, 96, 97; I. Reactive blue 1, 2, 7, 14, 15, 23, 32, 35, 38, 41, 63, 80, 95 etc. are mentioned.

  The content of the colorant is not particularly limited and may be appropriately selected depending on the purpose. However, since good color developability is obtained with respect to the total mass (100% by mass) of the ink, it is 2 to 10% by mass. Is preferred. The ink of the present embodiment may be a transparent clear ink that does not substantially contain a colorant.

〔water〕
The ink in the present embodiment may contain water. In particular, when the ink is a water-based ink, water is a main solvent of the ink, and becomes a component that evaporates and scatters when the recording medium is heated in ink jet recording.

  Examples of water include water from which ionic impurities have been removed as much as possible, such as pure water such as ion exchange water, ultrafiltration water, reverse osmosis water, and distilled water, and ultrapure water. Further, when water sterilized by ultraviolet irradiation or addition of hydrogen peroxide is used, generation of mold and bacteria can be prevented when the pigment dispersion and ink using the same are stored for a long period of time. This tends to improve the storage stability.

  The water content is not particularly limited and can be appropriately determined as necessary. An ink containing water or a water-based organic solvent as a main solvent corresponds to a water-based ink. The “main solvent” as used herein refers to the solvent component having the highest content among all the solvents in the ink. In addition, the “aqueous organic solvent” in the present specification means a mixed solvent of water and a water-soluble organic solvent.

〔Organic solvent〕
The ink in the present embodiment preferably further contains an organic solvent. Among the organic solvents, volatile water-soluble organic solvents are more preferable. The organic solvent is not particularly limited, and specifically, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,2 -Pentanediol, 1,2-hexanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol mono-n-propyl ether, ethylene glycol mono-iso-propyl ether, diethylene glycol Mono-iso-propyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-t-butyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monobutyl Ether, diethylene glycol mono-t-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-t-butyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-iso-propyl ether, propylene glycol mono- n-butyl ether, dipropylene glycol mono-n-butyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-iso-propyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol ethyl methyl ether, diethylene glycol Butylme Ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, tripropylene glycol dimethyl ether, methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, 2-butanol, alcohols or glycols such as tert-butanol, iso-butanol, n-pentanol, 2-pentanol, 3-pentanol, and tert-pentanol, N, N-dimethylformamide, N, N-dimethylacetamide, 2-pyrrolidone, N-methyl-2-pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, Examples include sulfolane and 1,1,3,3-tetramethylurea.

  An organic solvent may be used individually by 1 type, and may be used in combination of 2 or more type. The content of the organic solvent is not particularly limited, and can be appropriately determined as necessary. For example, when the ink has excellent permeability to the recording medium, one or more selected from the group consisting of 1,2-hexanediol, triethylene glycol monobutyl ether, and dipropylene glycol monopropyl ether Is preferably used.

  The total content of water and organic solvent may be 60 to 98% by mass with respect to the total mass (100% by mass) of the ink.

[Other ingredients]
In addition to the materials described above, the ink of the present embodiment may further contain a pH adjuster such as triethanolamine and tripropanolamine, an antiseptic / fungicide, a rust inhibitor, a chelating agent, and the like.

[Ink production method]
The ink of the present embodiment can be obtained by mixing the above-described materials (components) in an arbitrary order, performing filtration or the like as necessary, and removing impurities. Here, 10-30 degreeC is preferable as the temperature at the time of mixing said surfactant. In addition, it is preferable that the pigment is prepared in a state of being uniformly dispersed in a solvent and then mixed, since handling becomes simple.

  As a method for mixing each material, a method in which materials are sequentially added to a container equipped with a stirring device such as a mechanical stirrer or a magnetic stirrer and stirred and mixed is preferably used. As a filtration method, for example, centrifugal filtration or filter filtration can be performed as necessary.

  As described above, according to the present embodiment, the ink supply system excellent in initial filling property and continuous printing stability and the ink jet recording apparatus equipped with the ink supply system can be suitably used, and further, in dissolution stability and storage stability. Also excellent ink can be provided.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. The present invention is not limited in any way by the following examples.

[Materials used]
The main materials used in the following examples and comparative examples are as follows.

〔dye〕
・ C. I. Direct Blue 199
[Pigment]
・ PB15: 4 (copper phthalocyanine pigment)

[Surfactant]
(1. Alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain)
Surfactant 1: Nissin Chemical Industry Co., Ltd .; Orphine EXP4300: Main chain carbon number 12, with addition of ethylene oxide, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol ethoxy rate

(2. Acetylene glycol having 10 or more carbon atoms in the main chain)
Surfactant 2: manufactured by Air Products; Surfynol DF110D: Main chain 12 carbon atoms, no addition of ethylene oxide, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol Activator 3; manufactured by Air Products; Surfynol 104PG50: Main chain carbon number 10, no addition of ethylene oxide, 2,4,7,9-tetramethyl-5-decyne-4,7-diol

(3. Other acetylene glycol compounds)
Surfactant 4: Nissin Chemical Industry Co., Ltd .; Orphine E1010: Main chain carbon number 10, ethylene oxide addition mole number 10, 2,4,7,9-tetramethyl-5-decyne-4,7- Diol ethoxylate / surfactant 5: manufactured by Nissin Chemical Industry Co., Ltd .; Orphine E1004: main chain carbon number 10, ethylene oxide addition mole number 4, 2,4,7,9-tetramethyl-5-decyne-4 , 7-diol ethoxylate / surfactant 6: manufactured by Nissin Chemical Industry Co., Ltd .; Orphine 82W: main chain carbon number 8, no addition of ethylene oxide, 3,6-dimethyl-4-octyne-3,6- Diol

[Polyoxyalkylene alkyl ether]
POAAE1 (HLB value 15.0): manufactured by Daiichi Kogyo Seiyaku; Neugen DL-0415
POAAE1 is represented by the following general formula. In the formula, R is alkyl having 12 carbons, w + y = 15, x + z = 4.
_{RO (C 2 H 4 O)} w (C 3 H 6 O) x (C 2 H 4 O) y (C 3 H 6 O) z H
POAAE2 (HLB value 12.0): manufactured by Daiichi Kogyo Seiyaku; Neugen ET-116B
POAAE2 is represented by the following general formula. In the formula, R is alkyl having 12 carbons.
RO (C ₂ H ₄ O) ₇ (C ₃ H ₆ O) ₅ H
POAAE3 (HLB value 10.9): manufactured by Daiichi Kogyo Seiyaku; Neugen ET-106A
POAAE3 is represented by the following general formula. In the formula, R is alkyl having 12 carbons.
RO (C ₂ H ₄ O) ₅ (C ₃ H ₆ O) ₄ H

〔Organic solvent〕
Triethylene glycol triethylene glycol monobutyl ether (hereinafter referred to as “TEGmBE”)
・ Propylene glycol ・ Dipropylene glycol ・ Glycerin ・ Triethanolamine

[Examples 1-9, Comparative Examples 1-10, Reference Examples 1-2]
Each maintenance liquid was prepared by mixing and stirring each component according to the composition shown in Table 1 and Table 2 below. In addition, the comparative example 10 is a comparative example which does not use a maintenance liquid. Each maintenance solution was filtered with a membrane filter having a pore size of 1 μm to remove impurities. In Tables 1 and 2 below, the unit of numerical values is mass%, and the total is 100.00 mass%.

[Ink composition]
Each ink composition (hereinafter also simply referred to as “ink”) was prepared by mixing and stirring each component according to the composition shown in Table 3 below. Further, each ink composition was filtered with a membrane filter having a pore size of 1 μm to remove the impurities. In Table 3 below, the unit of numerical values is% by mass, and the total is 100.00% by mass.

[Measurement and evaluation methods]
[1. (Evaluation of dissolution stability)
About each prepared maintenance liquid, visual observation was performed whether the material component was melt | dissolving (dispersing) uniformly.
The evaluation criteria are as follows. The evaluation results are shown in Table 4 below.
○: The raw material components of the maintenance liquid were uniformly dissolved (dispersed), and undissolved suspended matter was not observed.
X: The raw material component of the maintenance liquid did not dissolve (disperse), and the undissolved residue was observed as a suspended matter.

[2. (Evaluation of storage stability)
Each of the prepared maintenance liquids was placed in a 20-ml glass bottle with a lid and left at 70 ° C. for 1 week. The liquid level of the maintenance liquid was observed, and the presence or absence of suspended matter was visually confirmed. Furthermore, when the maintenance liquid was filtered with a filter having a pore diameter of 10 μm, the presence or absence of collected matter (filtered matter) was confirmed.
The evaluation criteria are as follows. The evaluation results are shown in Table 4 below.
○: No suspended matter derived from the maintenance liquid component was observed, and no collected matter was obtained.
(Triangle | delta): Although the suspended | floating matter derived from the maintenance liquid component was observed, the collection thing was not obtained (no problem in practical use).
X: A collected product in which suspended matters derived from the maintenance liquid component were observed was obtained.

[3. (Evaluation of initial fillability)
20 g of each prepared maintenance liquid was filled in an ink tank of an ink jet printer (L100 [product name], manufactured by Seiko Epson Corporation). Thereafter, according to the initial filling sequence defined by L100, the maintenance liquid was discharged out of the head via the ink supply path 42 and the ink storage chamber. Next, after filling the ink tank with ink, the power ink flushing determined by L100 is operated twice to perform the ink filling operation to the head, and the ink is supplied from the ink container of the ink tank to the ink supply path 42 and The head was filled up through the ink storage chamber. Thereafter, a nozzle check was performed to confirm whether ink could be ejected from all nozzles of the head. When there was a nozzle that could not eject ink, the head was cleaned (suction of ink in the nozzle), and then the nozzle check was performed again. Based on the number of cleanings required until ink can be ejected from all nozzles, the initial filling property was evaluated according to the following evaluation criteria. In the case of Comparative Example 10 in which no maintenance liquid is used, the ink tank is filled with ink from the beginning and an initial filling sequence is performed (a normal method). The evaluation results are shown in Table 4 below.
○: Ejected from all nozzles only in the initial filling sequence.
(Triangle | delta): The frequency | count of cleaning required until ink can be discharged from all the nozzles was 1 time.
X: The number of cleanings required until ink could be ejected from all nozzles was 2 or more.

  The ink jet printer (L100 [product name], manufactured by Seiko Epson Corporation) includes a liquid storage chamber having an air inlet, and generates bubbles from the air inlet in the ink stored in the liquid storage chamber. An ink storage container in which air is introduced into the liquid storage chamber, a print head having a nozzle for ejecting ink, an ink storage container and the ink supply path for connecting the print head and supplying ink from the ink storage container to the print head And a filter provided in the ink supply path.

[4. (Evaluation of continuous printing stability)
After confirming that ink can be ejected from all nozzles of the head by the above “3. Evaluation of initial filling property”, each ink composition and A4 size plain paper (P paper [product name], manufactured by Fuji Xerox Co., Ltd.) The continuous printing stability was evaluated by printing a 70% duty image. The total number of prints was 1,000 by performing 500 continuous prints twice. Thereafter, a nozzle check was performed, and continuous printing stability was evaluated based on the following evaluation criteria based on the number of missing nozzles. The evaluation results are shown in Table 4 below.
A: The number of nozzle missing occurred was 1 or less.
(Triangle | delta): The frequency | count that nozzle missing generate | occur | produced was two.
X: The number of nozzle omissions was 3 or more.

  From the results of Table 4 above, maintenance comprising an alkylene oxide adduct of acetylene glycol having a main chain having 12 or more carbon atoms, an acetylene glycol having 10 or more carbon atoms in the main chain, and a polyoxyalkylene alkyl ether The liquid (each example) is superior in dissolution stability and storage stability compared to other maintenance liquids (each comparative example), and by using this, the initial filling property and continuous printing stability of the ink are improved. Was also found to be excellent.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 10 ... Conveyance unit, 11 ... Feed roller, 13 ... Conveyance roller, 14 ... Platen, 15 ... Discharge roller, 20 ... Carriage unit, 21 ... Carriage, 21a ... Ink supply needle, 22 ... Sub tank, 24 DESCRIPTION OF SYMBOLS ... Guide shaft, 30 ... Head unit, 31 ... Head, 40 ... Ink storage unit, 41 ... Ink storage container, 42 ... Ink supply path, 43 ... Filter, 45 ... Container body, 50 ... Detector group, 53 ... Paper detection Sensor, 54 ... Optical sensor, 60 ... Controller, 61 ... Interface unit, 62 ... CPU, 63 ... Memory, 64 ... Unit control circuit, 110 ... Computer, 202 ... Liquid receiving unit, 204 ... Ink storage chamber, 206 ... Filter, 208: Ink flow path 302: Plug member 304: Liquid injection path 306 Liquid 317 ... Air inlet, 340 ... Air storage chamber, 340 ... Liquid storage chamber, 350 ... Liquid chamber communication passage, 351 ... Air chamber side opening, 352 ... Air inlet, 370C1 ... No. 1 wall, 370C2 ... second wall (top wall), 370C3 ... bottom wall, d1 ... (steady state) water head difference, G ... bubble, Ga ... bubble, Gb ... microbubble, LA ... atmospheric contact liquid level (ink) Liquid level), LF ... ink liquid level, LM1 ... first state display line, LM2 ... second state display line, sf ... horizontal plane.

Claims (12)

An alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain;
Acetylene glycol having 10 or more carbon atoms in the main chain;
Including polyoxyalkylene alkyl ethers,
Maintenance liquid.   The maintenance liquid according to claim 1, wherein the polyoxyalkylene alkyl ether has an HLB value of 12 to 16.   The maintenance liquid according to claim 1 or 2, wherein the alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain includes an ethylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain. .   The content of the polyoxyalkylene alkyl ether, and the total content of acetylene glycol having an alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain and 10 or more carbon atoms in the main chain, The maintenance liquid according to any one of claims 1 to 3, wherein the mass ratio is in a range of 0.10: 1.0 to 0.50: 1.0.   The maintenance liquid according to any one of claims 1 to 4, wherein the alkylene oxide adduct of acetylene glycol having 12 or more carbon atoms in the main chain has an HLB value of 8 to 15.   The maintenance liquid according to any one of claims 1 to 5, wherein the acetylene glycol having 10 or more carbon atoms in the main chain has an HLB value of 4 or less.   The maintenance liquid according to any one of claims 1 to 6, further comprising an organic solvent. An ink storage container including a liquid storage chamber having an air inlet, wherein air is generated from the air inlet into the liquid stored in the liquid storage chamber, thereby generating bubbles in the liquid;
A print head having a nozzle for discharging the liquid;
An ink supply path for connecting the ink container and the print head and supplying the liquid from the ink container to the print head,
The maintenance liquid according to any one of claims 1 to 7 is provided as the liquid in at least one of the liquid storage chamber and the ink supply path.
Ink supply system.   The ink supply system according to claim 8, further comprising a filter in the ink supply path, wherein an average pore diameter of the filter is equal to or smaller than a nozzle diameter of the nozzle.   The ink supply system according to claim 8 or 9, wherein a plurality of the filters are provided in the ink supply path.   The ink supply system according to claim 8, wherein a material of the filter is resin. An ink supply system according to any one of claims 8 to 11, comprising:
An ink jet recording apparatus that ejects ink supplied from the ink container to the print head from the print head toward a recording medium.