Inkjet printer

Abstract

The ink-jet printer comprises an ink box, the ink box comprises an ink storage part and a printing head with a nozzle row, a partition plate is vertically arranged in the ink storage part and divides the space in the ink storage part into a first cavity and a second cavity, an ink inlet allowing ink to enter is formed in the first cavity, and sponge is arranged in the second cavity; a strip-shaped gap is formed in the partition plate in the vertical direction, the width of the gap is k, the thickness of the gap is t, the length of the gap is h, k is larger than or equal to 0.5 mm and smaller than or equal to 3 mm, t is larger than or equal to 0.5 mm and smaller than or equal to 5 mm, and h is larger than or equal to 10 mm. The surface tension of ink used in the ink box is F, and F is larger than 30 mN / m. According to the ink-jet printer, ink can be immersed into the sponge through the gaps based on the capillary action, the speed of supplying the ink into the sponge is restrained, meanwhile, the ink storage amount in the sponge is small, the adsorption force to the ink can be kept all the time, and ink leakage at the nozzle position is restrained. Even if the capillary action of the nozzle position is weakened due to increase of evaporation viscosity, increase of density, reduction of ink surface tension and reduction of ink surface tension, ink leakage can be overcome.

Description

Technical Field

[0001] The invention relates to an inkjet printer. Background Art

[0002] Inkjet printers convert colored or colorless ink into fine liquids and spray them onto printing paper through nozzles. Various types of inkjet printers have been developed for industrial, commercial, and home use. Among commercial and home printers, continuous supply inkjet printers have become popular in recent years due to the increase in printing capacity. Inkjet printers usually have ink cartridges, which include an ink storage unit and a print head with a nozzle array arranged at the ink outlet position of the ink cartridge. In order to ensure stable ink supply, a sponge is also placed in the ink cartridge to control the ink supply speed.

[0003] In the prior art, ink usually enters the ink cartridge directly from the top of the sponge. The ink can easily and quickly fill the sponge, and the sponge loses its attraction to the ink, causing the ink to leak directly from the nozzle due to gravity, which is prone to ink leakage. In addition, after long-term use, the water in the ink will evaporate, causing the ink viscosity and density to increase, and the corresponding surface tension of the ink to decrease. The increase in ink viscosity, density, and decrease in ink surface tension will weaken the capillary action, which may cause the ink to leak from the nozzle. In particular, in inkjet printers, due to the large ink capacity, the ink is stored inside the printer for a long time. When the amount of ink evaporation increases, the above-mentioned ink leakage is prone to occur. Summary of the invention

[0004] The technical problem to be solved by the present invention is to suppress the speed of supplying ink to the sponge and thus suppress the problem of ink leakage from the nozzle. At the same time, it can also suppress the leakage of ink from the nozzle when the water in the ink evaporates.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: an inkjet printer, comprising an ink cartridge, the ink cartridge comprising an ink storage part and a print head having a nozzle array, a partition is vertically arranged in the ink storage part, the partition separates the space in the ink storage part into a first cavity and a second cavity, the first cavity is provided with an ink inlet for ink to enter, and a sponge is arranged in the second cavity;

[0006] The partition plate is provided with a strip-shaped gap vertically on its upper edge, wherein the width of the gap is k, the thickness is t, and the length is h, wherein 0.5 mm ≤ k ≤ 3 mm, 0.5 mm ≤ t ≤ 5 mm, and h ≥ 10 mm;

[0007] The surface tension of the ink used in the ink cartridge is F, and F>30mN / m.

[0008] In order to allow the ink to enter the sponge more evenly, the gap is preferably located at the center of the partition in the left-right direction.

[0009] In order to ensure that the air pressure in the two cavities is balanced, it is preferred that there is a gap between the top end of the partition and the top surface of the ink cartridge.

[0010] In order to suppress the foaming of ink during the printing process and affect the ink supply effect, the ink used in the ink cartridge preferably includes a foam-suppressing surfactant, and the surfactant is at least one of an acetylene glycol surfactant, a silicon-based surfactant, and a fluorine-based surfactant.

[0011] Preferably, the surfactant in the ink used in the ink cartridge is an acetylene glycol type surfactant, and the acetylene glycol type surfactant is of the general formula (1);

[0012]

[0013] In the general formula (1), m+n≤15.

[0014] Preferably, the mass ratio of the surfactant in the ink is greater than or equal to 0.1 wt %.

[0015] Furthermore, the ink preferably contains a polyoxyethylene alkyl ether compound represented by the general formula (2);

[0016]

[0017] In formula (2), k is 10 to 25, and R3 is a straight chain or branched chain alkyl group having 12 to 22 carbon atoms.

[0018] In order to improve the dissolution recovery ability of the ink after drying and reduce the amount of ink adhering to the inner wall of the ink cartridge, the ink used in the ink cartridge preferably includes a polyol as a humectant, and the mass ratio of the polyol in the ink is preferably in the range of 10wt% to 35wt%.

[0019] In order to reduce the amount of ink adhering to the inner wall of the ink cartridge, it is preferred that the viscosity of the ink used in the ink cartridge is less than or equal to 5 cP at 25°C.

[0020] In order to improve the dissolution recovery ability of the ink after drying, it is preferred that the solid content of the colorant in the ink used in the ink cartridge is less than or equal to 10 wt %.

[0021] Compared with the prior art, the advantages of the present invention are: the inkjet printer of the present invention divides the space in the ink cartridge into two chambers through a partition, and a gap is vertically arranged on the partition. When in use, the ink first enters the first chamber, and then penetrates into the sponge in the second chamber horizontally and upwards through the gap based on capillary action. Compared with the ink directly penetrating into the sponge of the ink cartridge from the top of the ink cartridge based on gravity, the speed of supplying ink to the sponge can be effectively suppressed. At the same time, based on the capillary action generated by the gap, the ink penetrates upward from the bottom of the sponge, and the ink stock in the sponge is small, so that the sponge always maintains the adsorption force on the ink, thus effectively suppressing the leakage of ink at the nozzle position. Even if the ink viscosity increases, the density increases, and the surface tension of the ink decreases due to evaporation, so that the capillary action at the nozzle position is weakened, the ink leakage problem caused by the weakened capillary action at the nozzle position can be effectively overcome based on the negative pressure of the ink cartridge itself and the adsorption force of the sponge. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a three-dimensional diagram of an ink cartridge carrying four types of inks in an embodiment of the present invention.

[0023] Figure 2 It is a cross-sectional view of an ink cartridge carrying four types of inks in an embodiment of the present invention.

[0024] Figure 3 It is a cross-sectional view of another section of the ink cartridge carrying four types of inks in an embodiment of the present invention.

[0025] Figure 4 This is a cross-sectional view of another section of the ink cartridge carrying four types of inks in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below with reference to the accompanying drawings.

[0027] like Figures 1 to 4 As shown, the inkjet printer in this embodiment includes an ink cartridge, which includes an ink storage portion 1 and a print head 2 having a nozzle array. The number of ink storage portions 1 is specifically determined according to the functional requirements of the printer, and the print head 2 can be the print head 2 used in existing inkjet printers.

[0028] A partition 3 is vertically arranged in the ink storage part 1, and the partition 3 separates the space in the ink storage part 1 into a first cavity 11 and a second cavity 12. The first cavity 11 is provided with an ink inlet 111 for ink to enter, and the second cavity 12 is provided with a sponge 4. The ink enters the first cavity 11 from the ink inlet 111, and then flows into the second cavity 12 and is immersed in the sponge 4. The bottom of the second cavity 12 is provided with an ink outlet, and the print head 2 is arranged on the bottom corresponding to the ink outlet. The best state of the print head is that no ink leakage occurs at the position of the nozzle of the print head 2, so that the printing quality can be guaranteed, and the problem of nozzle clogging of the print head 2 can also be avoided.

[0029] In order to allow the ink entering the first cavity 11 to flow smoothly into the second cavity 12, a strip-shaped gap 31 is vertically opened on the partition 3. Preferably, the gap 31 extends from the bottom to the top of the partition 3. In order to allow the ink to enter the second cavity 12 more evenly and be evenly immersed in the sponge 4, the gap 31 is preferably located at the center position of the partition 3 in the left-right direction.

[0030] Based on the structure of the slit 31, the ink can enter the second cavity 12 at a low speed under the capillary action and slowly soak into the sponge 4. The slit 31 effectively suppresses the speed of supplying ink to the sponge 4, so the ink usually does not soak into the upper position of the sponge 4. The upper part of the sponge 4 can remain unsoaked in ink, which can effectively maintain the adsorption force of the sponge 4 on the ink. At the same time, after the ink enters the first cavity 11, it moves upward under the capillary action of the slit 31 and soaks into the sponge 4, increasing the contact area with the sponge 4 in the second cavity 12, which can ensure sufficient ink supply capacity.

[0031] Based on the range of speeds required for supplying ink to the sponge 4, it is necessary to ensure that the ink can be supplied normally for printing, and to avoid the ink filling the sponge 4 and causing ink leakage at the nozzle of the print head 2, so it is necessary to restrict the size of the gap 31 so that it can generate a suitable capillary force on the ink. The width of the gap 31 is k, the thickness is t, and the length is h, where 0.5 mm ≤ k ≤ 3 mm, 0.5 mm ≤ t ≤ 5 mm, and h ≥ 10 mm.

[0032] When k is less than 0.5 mm, the ink supply from the first cavity 11 to the second cavity 12 may be insufficient during high-speed printing, which may affect the printing quality. When k exceeds 3 mm, the capillary action of the gap 31 may be insufficient, and ink may leak from the nozzle. Preferably, k is 0.5 mm ≤ k ≤ 2 mm.

[0033] When t is less than 0.5 mm, the capillary action of the gap 31 is sometimes insufficient, and ink leakage from the nozzle sometimes occurs. When t exceeds 5 mm, the ink supply from the first cavity 11 to the second cavity 12 is sometimes insufficient during high-speed printing, and the printing quality is sometimes affected. Preferably, t is 0.5 mm ≤ t ≤ 3 mm.

[0034] When h is less than 10 mm, the capillary action of the slit 31 may be insufficient, and ink may leak from the nozzle. Preferably, h is h≥15 mm.

[0035] The width k, thickness t and length h of the gap 31 are specifically set according to the volume of the ink storage portion 1 and the volumes of the first cavity 11 and the second cavity 12 .

[0036] In order to allow the ink to enter the sponge more evenly, the gap is preferably located at the center of the partition in the left-right direction.

[0037] In order to ensure that the air pressure in the two cavities is balanced, it is preferred that there is a gap between the top end of the partition and the top surface of the ink cartridge.

[0038] The inkjet printer of the present invention divides the space of the ink storage part in the ink cartridge into two cavities through the partition 3, and a slit 31 is vertically arranged on the partition 3. When in use, the ink first enters the first cavity 11, and then penetrates into the sponge 4 in the second cavity 12 horizontally and upwards through the slit 31 based on the capillary action. Compared with the ink directly penetrating into the sponge 4 of the ink cartridge 1 from the top based on gravity, the speed of supplying ink to the sponge 4 can be effectively suppressed. At the same time, based on the capillary action generated by the slit 31, the ink penetrates upward from the bottom of the sponge 4, and the ink storage in the sponge 4 is small, so that the sponge 4 always maintains the adsorption force on the ink, which effectively suppresses the ink leakage at the nozzle position. Even if the ink viscosity increases, the density increases, and the surface tension of the ink decreases due to evaporation, so that the capillary action at the nozzle 2 position is weakened, the ink leakage problem caused by the weakened capillary action at the nozzle 2 position can be effectively overcome based on the negative pressure of the ink cartridge 1 itself and the adsorption force of the sponge 4.

[0039] On the basis of improving the structure of the ink storage part in the ink cartridge, this embodiment also improves and optimizes the ink components used in the ink cartridge, further suppressing the ink leakage problem in the nozzle column caused by the evaporation of water in the ink, and at the same time suppressing the occurrence of ink precipitates and ink supply performance. The specific contents of the optimization of the ink are as follows.

[0040] 1. Ink properties

[0041] 1.1 Surface tension

[0042] Based on the need for the ink to enter the second cavity 12 through the capillary action brought by the gap 31, in order to make the capillary force meet the requirements, so that the ink can smoothly enter the second cavity 12 and reach the design speed, it is necessary to impose certain restrictions on the surface tension of the ink entering the ink cartridge. The surface tension of the ink used in the ink cartridge is F, F≧30mN / m. Based on the restriction on the surface tension of the ink, it can be ensured that the ink enters the second cavity 12 at the design speed and soaks into the sponge 4. The amount of ink entering can both prevent ink leakage from the nozzle of the print head 2 and ensure normal printing.

[0043] The surface tension F of the ink is more preferably F ≥ 32 mN / m.

[0044] 1.2 Viscosity

[0045] The ink used in the ink cartridge is supplied to the first cavity 11 from an ink bottle provided separately through an ink inlet 111 for the ink to enter. Since there is no sponge in the first cavity 11, the ink adheres to the inner wall of the first cavity 11. In order to reduce the amount of ink adhered to the inner wall of the first cavity 11, the viscosity of the ink at a temperature of 25° C. is preferably 5.0 cP or less. More preferably, it is 3.5 cP or less.

[0046] 1.3pH

[0047] The pH of the ink used in the ink cartridge at a temperature of 25° C. is preferably 5.0 to 10.0, and more preferably 7.0 to 9.5.

[0048] 2. Coloring Materials

[0049] The ink used in the ink cartridge may further include a coloring material, which may be at least one of a pigment and a dye.

[0050] 2.1 Dyes

[0051] The ink used in the ink cartridge may contain a dye. The dye is not particularly limited, and acid dyes, basic dyes, direct dyes, reactive dyes, etc. can be used.

[0052] For example, at least one of the following dyes may be used.

[0053] Direct dyes: CIDirect Black 19, CIDirect Black 51, CIDirect Black168, CIDirect Blue 1, CIDirect Blue 86, CIDirect Blue 199, CIDirect Red80, CIDirect Red 227, CIDirect Yellow-12, CIDirect Yellow-86, CIDirectYellow-132, etc.

[0054] Acid dyes: CIAcid Black 2, CIAcid Black 52, CIAcid Black 94, CIAcid Blue 9, CIAcid Blue 45, CIAcid Blue 254, CIAcid Red 1, CIAcid Red 52, CIAcid Red 249, CIAcid Red 289, CIAcid Yellow 17, CIAcid Yellow 23, CIAcid Yellow 71, etc.

[0055] Reactive dyes: CIReactive Black 19, CIReactive Black 39, CIReactiveBlack 154, CIReactive Red 14, CIReactive Red 141, CIReactive Red 221, CIReactive Blue 2, CIReactive Blue 101, CIReactive Blue 217, CIReactiveYellow 2, CIReactive Yellow 77, CIReactive Yellow 163, etc.

[0056] These dyes may be used alone or in combination of two or more.

[0057] 2.1 Pigments

[0058] The ink used in the ink cartridge may also contain a pigment. The pigment is not particularly limited, and any of inorganic pigments and organic pigments may be used. For example, phthalocyanine pigments, quinacridone pigments, dioxazine pigments, diketopyrrolopyrrole pigments, azo pigments, etc. may be used.

[0059] At least one of the following pigments can be used in each color ink.

[0060] Cyan pigment: CIPigment Blue 1, CIPigment Blue 2, CIPigment Blue 3, CIPigment Blue 15:3, CIPigment Blue 15:4, CIPigment Blue 16, etc.

[0061] Magenta pigments: CIPigment Red 5, CIPigment Red 7, CIPigment Red 122, CIPigment Red 150, CIPigment Red 202, CIPigment Violet 19, etc.

[0062] Yellow pigments: CIPigment Yellow 1, CIPigment Yellow 3, CIPigment Yellow74, CIPigment Yellow 128, CIPigment Yellow 129, CIPigment Yellow 155, etc.

[0063] In addition, the ink used in the ink cartridge may also use commercially available self-dispersible pigments, such as CAB-O-JET200, CAB-O-JET300, CAB-O-JET400, Cab-O-Jet4507C, Cab-O-Jet4607M, Cab-O-Jet4707Y, REGAL250, REGAL330 (Cabot), BONJET BLACK CW-1, BONJET BLACK CW-2, BONJET BLACK CW-3, BONJET BLACK CW-4 (Oriental Chemical), Tokai Black), Aritistri Nite DN240 (Dupont), etc.

[0064] These pigments may be used alone or in combination of two or more.

[0065] In order to improve the redissolution recovery ability or redispersion recovery ability after the ink is dried, the mass ratio of the coloring material is preferably 10 wt % or less.

[0066] 3. Surfactants

[0067] The ink in the ink cartridge preferably contains a surfactant. As the surfactant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant or a nonionic surfactant can be used. It is particularly preferred to use a nonionic surfactant. From the viewpoint of suppressing the generation of bubbles inside the ink storage portion 1, as the nonionic surfactant, acetylene glycol surfactants, fluorine surfactants and silicone surfactants are preferred.

[0068] As the nonionic surfactant, an acetylene glycol-based surfactant represented by formula (1) is more preferred.

[0069]

[0070] In the general formula (1), m+n≤15.

[0071] Preferably m+n≤12.

[0072] The content of the surfactant in the ink is 0.01 wt % to 3.0 wt %, preferably 0.05 wt % to 2.0 wt %, and more preferably 0.1 wt % to 1.0 wt %, relative to the total mass of the ink.

[0073] 4. Polyoxyethylene alkyl ether compounds

[0074] The ink of this embodiment preferably contains a polyoxyethylene alkyl ether compound represented by the general formula (2).

[0075]

[0076] In the general formula (2), k is 10 to 25, and R3 is a straight chain or branched chain alkyl group having 12 to 22 carbon atoms.

[0077] Ink is supplied to the first cavity 11 from an ink bottle provided separately through an ink inlet 111 for ink entry. Since there is no sponge in the first cavity 11, ink adheres to the inner wall of the first cavity 11. When not used for a long time, the adhered ink sometimes evaporates and condenses, and coloring materials and the like precipitate. When precipitates are generated, the precipitates block the gap of the slit 31, and there is a possibility that ink cannot be supplied to the print head.

[0078] The polyoxyethylene alkyl ether compound represented by the general formula (2) has a polyoxyethylene part as a hydrophilic part and an alkyl part as a hydrophobic part. The alkyl part as the hydrophobic part of the polyoxyethylene alkyl ether compound represented by the general formula (2) is adsorbed on the hydrophobic part of the precipitate such as the colorant, and the dispersibility or solubility is assisted by the polyoxyethylene part as the hydrophilic part. In addition, it is known that the polyoxyethylene chain chelates with metal ions. It can alleviate the salt precipitation caused by the increase of salt concentration due to the concentration of the ink and inhibit the generation of precipitates.

[0079] The content of the polyoxyethylene alkyl ether compound represented by the general formula (2) in the ink is 0.01 wt% to 3.0 wt%, preferably 0.05 wt% to 2.0 wt%, and more preferably 0.1 wt% to 1.0 wt%, relative to the total mass of the ink.

[0080] 5. Water-soluble organic solvents

[0081] The ink used in the ink cartridge contains a water-soluble organic solvent. Although not particularly limited, examples of the water-soluble organic solvent include at least one of the following substances.

[0082] Monohydric alcohol: methanol, ethanol, isopropanol, etc.

[0083] Polyols: ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-ethyl-2-methyl-1,3-propanediol, 2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol, trimethylolpropane, glycerol, etc.

[0084] Polyol ethers: ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, etc.

[0085] Ethylene glycol diesters: ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, methoxybutyl acetate, etc.

[0086] Cyclic esters: β-propiolactone, γ-butyrolactone, δ-valerolactone, etc.

[0087] Nitrogen-containing solvents: urea, ethylene urea, N-methyl-2-pyrrolidone, substituted pyrrolidones, etc.

[0088] In order to improve the dissolution recovery ability of the ink after drying and reduce the amount of ink attached to the inner wall of the ink storage part 1, the ink preferably contains a polyol as a humectant. The mass ratio of the polyol in the ink is preferably in the range of 10wt% to 35wt% relative to the total mass of the ink.

[0089] 6. Other ingredients

[0090] As other components, the ink may contain a pH adjuster, a mildew preventer / preservative, a rust preventer, an antioxidant, a reduction inhibitor, a drying agent, and the like.

[0091] As the antifungal agent and preservative, Proxel GXL, Proxel XL2, etc. can be used.

[0092] As the chelating agent, ethylenediaminetetraacetate, citrate, etc. can be used.

[0093] 7. Water

[0094] The water contained in the ink of the present invention is preferably deionized water, pure water, or ultrapure water from which metal ions and the like have been removed.

[0095] Example

[0096] Hereinafter, the present invention will be further described in conjunction with embodiments, comparative examples and reference examples.

[0097] Ink preparation

[0098] Tables 1-1, 1-2 and 1-3 show the inks of the embodiments, comparative examples and reference examples. The components listed in Tables 1-1, 1-2 and 1-3 were mixed, stirred for 30 minutes or longer, and then filtered using a 0.2 μm filter. In addition, the values ​​recorded in Tables 1-1, 1-2 and 1-3 are the mass percentages of the effective components. Water is used as the main solvent, and its addition amount is used to make up the balance to 100wt%.

[0099] Among them, Cab-O-Jet 400K: manufactured by Cabot; Surfynol 420: manufactured by EVONIK; Surfynol 440: manufactured by EVONIK; Surfynol 465: manufactured by EVONIK; Surfynol 485: manufactured by EVONIK; BYK-333: manufactured by BYK; Surflon S-243: manufactured by AGC Qingmei Chemical; Proxel GXL: manufactured by LONZA; Polyoxyethylene cetyl ether (k=10): k is the number of repetitions of the polyoxyethylene chain; Polyoxyethylene cetyl ether (k=20): k is the number of repetitions of the polyoxyethylene chain; Polyoxyethylene oleyl ether (k=20): k is the number of repetitions of the polyoxyethylene chain; Polyoxyethylene stearyl ether (k=25): k is the number of repetitions of the polyoxyethylene chain.

[0100] Table 1-1

[0101]

[0102] Table 1-2

[0103]

[0104] Table 1-3

[0105]

[0106] The inks listed in Tables 1-1, 1-2 and 1-3 were evaluated as follows.

[0107] Table 2-1

[0108]

[0109] Table 2-2

[0110]

[0111] The following experiments were conducted to evaluate the performance of the ink cartridge in terms of ink leakage, the generation of precipitates, and the ink supply performance.

[0112] Ink leakage

[0113] The inks of Tables 1-1, 1-2 and 1-3 were filled in the ink reservoir having the slits 31 described in Tables 2-1 and 2-2 in the combinations described in Tables 3-1, 3-2, 3-3 and 3-4. After printing 100 GB images on plain paper using an inkjet printer, ink leakage from the nozzle was confirmed. This operation was repeated 10 times and evaluated based on the following criteria.

[0114] Good: No ink leakage occurs.

[0115] Not good: Ink leakage has occurred.

[0116] Occurrence of precipitates

[0117] The ink cartridge used in the above-mentioned ink leakage evaluation was left for 2 weeks in an environment of 32° C. and 8% RH. After leaving, the precipitate in the first cavity 11 was checked and evaluated based on the following criteria.

[0118] Better: No precipitates appear.

[0119] Good: Powdery precipitate appears.

[0120] Bad: Particle-like precipitates appear.

[0121] Ink supply performance

[0122] Using the ink and ink cartridge used in the above evaluation, a solid image was printed on plain paper by printing one drop of ink per 600 dpi grid. Evaluation was performed according to the following criteria.

[0123] Better: Printing was performed without any defect in an environment of 5°C and 8%RH.

[0124] Good: Printing defects occurred due to insufficient ink supply in the 5°C and 8% RH environment, but printing was performed without defects in the 15°C and 8% RH environment.

[0125] Bad: Printing defects due to insufficient ink supply occurred in both 5℃ and 8% RH environments and 15℃ and 8% RH environments.

[0126] Table 3-1

[0127]

[0128] Table 3-2

[0129]

[0130] Table 3-3

[0131]

[0132] Table 3-4

[0133]

[0134] It should be noted that the ink leakage prevention, inhibition of precipitate occurrence and ink supply performance in Examples 1-28 and Comparative Examples 01-07 in Tables 3-1, 3-2, 3-3 and 3-4 are all compared with the reference examples in Table 3-4. From the comparison results, the ink leakage prevention, inhibition of precipitate occurrence and ink supply performance are different due to the difference in the structure of the partition 3 in the ink storage part 1 in the ink cartridge, the difference in the parameters of the gap 31 on the partition 3, and the difference in the ink composition used in the ink cartridge.

[0135] Specifically, for Examples 1-20, a partition is provided in the ink storage portion 1 of the ink cartridge, and the length, width and height of the gap 31 on the partition 3 are all within the aforementioned preferred distance range, and the ink used in the ink cartridge contains a color material with a solid content of less than 10wt%, a polyol with a content between 10wt% and 35wt%, an acetylene glycol-type surfactant and a polyoxyethylene alkyl ether compound, so that the properties of preventing ink leakage, inhibiting the occurrence of precipitates and ink supply performance are all in the best state.

[0136] For Examples 21-28, a partition is provided in the ink storage part 1 in the ink cartridge, and the length, width and height of the gap 31 on the partition 3 are all within the aforementioned preferred distance range, so the ink leakage resistance of the ink cartridge is in the best state. However, since the solid content of ink-16 used in Example 21 exceeds the upper limit, the risk of color material precipitation increases after water evaporation; the polyol content of ink-18 used in Example 23 is lower than the lower limit of the aforementioned range, the water in the ink is easy to evaporate, and the risk of color material precipitation increases; the ink-20 used in Example 25 does not contain polyoxyethylene alkyl ether compounds; the ink is not resolubility after drying and precipitation, so the performance of inhibiting the occurrence of precipitates in these three examples is poor, and the evaluation is only good. In addition, since the viscosity of ink-17 used in Example 22 exceeds the upper limit, there will be a risk of insufficient ink supply when printing high coverage images, and the polyol content of ink-19 used in Example 24 exceeds the upper limit, the viscosity increases; there will be a risk of insufficient ink supply, so the ink supply performance of Examples 22 and 24 is poor, and the evaluation is only good.

[0137] For Comparative Example 01, when the surface tension is lower than the lower limit, the capillary force decreases, the probability of ink leakage from the nozzle hole increases, and the ink leakage prevention property of the ink cartridge is in a poor state.

[0138] For Comparative Example 02, since the gap width exceeds the lower limit, the permeability of the ink decreases, resulting in insufficient ink supply, and the ink supply performance of the ink cartridge is in a poor state.

[0139] For Comparative Example 03, ink cartridge-8 is used. Although a partition 3 is provided in the ink storage portion 1 of the ink cartridge, the width of the gap 31 on the partition 3 exceeds the preferred width range, that is, the width of the gap 31 is too large, resulting in too fast ink supply speed, and thus the ink leakage prevention property of the ink cartridge is poor.

[0140] In Comparative Example 04, since the capillary force is small, the ink leakage prevention property of the ink cartridge is poor.

[0141] For comparison example 05, ink cartridge-10 is used. Although a partition 3 is set in the ink storage part 1 of the ink cartridge, the thickness of the gap 31 on the partition 3 exceeds the preferred thickness range, resulting in a too slow ink supply speed, so the ink supply performance of the ink cartridge is poor.

[0142] For Comparative Example 06, ink cartridge-10 is used. Although a partition 3 is provided in the ink storage portion 1 of the ink cartridge, since the height of the gap 31 on the partition 3 is smaller than the preferred height range, the gap 31 does not sufficiently slow down the ink supply speed, and thus the ink leakage prevention property of the ink cartridge is poor.

[0143] For Comparative Example 07, since the partition 3 is not provided in the ink storage part 1 of the ink cartridge-12 used, the ink is directly absorbed into the sponge and the ink supply speed is too fast, so the ink leakage prevention property of the ink cartridge is poor.

[0144] In the specification and claims of the present invention, terms indicating directions, such as "front", "rear", "up", "down", "left", "right", "side", "top", "bottom", etc., are used to describe various exemplary structural parts and elements of the present invention, but these terms are used here only for the purpose of convenience of description and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in the present invention can be arranged in different directions, these terms indicating directions are only used as explanations and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

Claims

1. An inkjet printer, comprising an ink cartridge, wherein the ink cartridge comprises an ink storage portion (1) and a print head (2) having a nozzle array, wherein: A partition (3) is vertically arranged in the ink storage portion (1), and the partition (3) separates the space in the ink storage portion (1) into a first cavity (11) and a second cavity (12); the first cavity (11) is provided with an ink inlet (111) for ink to enter, and the second cavity (12) is provided with a sponge (4); A strip-shaped gap (31) is vertically provided on the partition (3), wherein the width of the gap (31) is k, the thickness is t, and the length is h, wherein 0.5 mm ≤ k ≤ 3 mm, 0.5 mm ≤ t ≤ 5 mm, and h ≥ 10 mm; The surface tension of the ink used in the ink cartridge is F, and F>30mN / m.

2. The inkjet printer according to claim 1, characterized in that: The gap (31) is located at the center of the partition (3) in the left-right direction.

3. The inkjet printer according to claim 1, characterized in that: There is a gap (32) between the top end of the partition (3) and the top surface of the ink storage portion (1).

4. The inkjet printer according to any one of claims 1 to 3, characterized in that: The ink used in the ink cartridge includes a surfactant capable of suppressing foaming, and the surfactant is at least one of an acetylene glycol surfactant, a silicon-based surfactant, and a fluorine-based surfactant.

5. The inkjet printer according to claim 4, characterized in that: The surfactant in the ink used in the ink cartridge is an acetylene glycol type surfactant, and the acetylene glycol type surfactant is of the general formula (1); In the general formula (1), m+n≤15.

6. The inkjet printer according to any one of claims 1 to 3, characterized in that: The ink includes a polyoxyethylene alkyl ether compound represented by general formula (2); In formula (2), k is 10 to 25, and R3 is a straight chain or branched chain alkyl group having 12 to 22 carbon atoms.

7. The inkjet printer according to any one of claims 1 to 3, characterized in that: The ink used in the ink cartridge includes polyol as a humectant, and the mass ratio of the polyol in the ink is in the range of 10wt% to 35wt%.

8. The inkjet printer according to any one of claims 1 to 3, characterized in that: The viscosity of the ink used in the ink cartridge at 25° C. is less than or equal to 5 cP.

9. The inkjet printer according to any one of claims 1 to 3, characterized in that: The solid content of the color material in the ink used in the ink cartridge is less than or equal to 10 wt %.

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