Water-based pigment ink for TIJ type ink-jet printer

Abstract

The invention belongs to the technical field of printing, and particularly relates to water-based pigment ink for a TIJ type ink-jet printer, and the water-based pigment ink comprises the following components: pigment color paste, N-ethyl pyrrolidone, a water-soluble organic solvent, an alkyne diol surfactant, a wetting agent consisting of acetylene ethanol and acetylene diol, and the balance of water. Compared with the prior art, the water-based pigment black ink keeps a long-time standby state in a printer nozzle without drying the nozzle, the cover opening time of an ink-jet printer is 2 hours or more, the ink can continuously print without blocking the nozzle, meanwhile, the ink is good in fluency and compatibility, and the service life of the ink-jet printer nozzle is longer than that of common ink.

Description

Technical Field

[0001] This invention relates to the field of printing technology, and in particular to a water-based pigment ink for the TIJ inkjet printer model. Background Technology

[0002] As the packaging printing market gradually shifts from mass production to personalized and diversified printing, traditional printing is accelerating its transformation towards digital printing. Under this trend, inkjet printing technology, with its high efficiency, on-demand printing, and variable information printing capabilities, is gradually becoming a complementary technology for carton printing companies, forming an advantage with existing printing methods, workflows, and supply chains. Simultaneously, increasingly stringent environmental regulations are driving the upgrading of ink materials towards lower volatile organic compound (VOC) emissions. Water-based environmentally friendly inks, due to their environmental friendliness, have become the mainstream choice in the industry, significantly increasing their application share in the inkjet printing field.

[0003] The current mainstream water-based inkjet ink formulation mainly consists of pigment paste, solvent, surfactant, antibacterial agent, and deionized water. The solvent system primarily uses diethylene glycol and propylene glycol, while modified siloxane surfactants are commonly used. However, when this formulation of water-based inkjet ink is applied to industrial coding machines (TIJ models), the printing efficiency is relatively low and fails to meet production efficiency requirements. Increasing the printing speed easily leads to printing defects such as missing lines, blurred text, and ink droplets. Increasing the number of coding machines, on the other hand, raises concerns about increased equipment costs and floor space requirements. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to overcome the defects or deficiencies of the prior art and provide a water-based pigment ink that maintains ink continuity and good printing effect when printing at high speed of 50m / min on the TIJ inkjet printer.

[0005] A water-based pigment ink, comprising the following components: pigment paste, N-ethylpyrrolidone, water-soluble organic solvent, acetylenol surfactant, acetylenol ethanol and acetylenol forming a wetting agent, and the balance being water.

[0006] Compared to existing technologies, the water-based pigment black ink of this invention keeps the printhead dry for extended periods, allowing the inkjet printer to remain open for more than 2 hours. The ink can print continuously without clogging the printhead. Furthermore, this ink has good fluidity, good compatibility, and a longer printhead lifespan than ordinary inks.

[0007] In one embodiment, the N-ethylpyrrolidone is present in the aqueous pigment ink at a weight percentage of 25%-35%.

[0008] In one embodiment, the water-soluble organic solvent is selected from at least one of ethylene glycol, propylene glycol, 1,2-hexanediol, 1,2-propanetriol, 1,2-propanediol, diethylene glycol, triethylene glycol, and sorbitol.

[0009] In one embodiment, the water-soluble organic solvent includes ethylene glycol, and the weight percentage of ethylene glycol in the water-based pigment ink is 3%-10%.

[0010] In one embodiment, the wetting agent formed by acetylene ethanol and acetylene diol is a synthetic reactant of acetylene ethanol and acetylene diol, with the following molecular formula: .

[0011] In one embodiment, the HLB value of the wetting agent composed of acetylene ethanol and acetylene diol is 13-14, and the weight percentage of the wetting agent composed of acetylene ethanol and acetylene diol in the water-based pigment ink is 0.1%-0.5%.

[0012] In one embodiment, the weight percentage of the acetylacetonate surfactant in the aqueous pigment ink is 0.1%-2%.

[0013] In one embodiment, the pigment ink further includes a preservative, wherein the preservative accounts for 0.1% to 1% of the pigment ink by mass.

[0014] In one embodiment, the viscosity of the aqueous pigment ink is 3.0 Pa·s to 4.0 Pa·s.

[0015] In one embodiment, the surface tension of the water-based pigment ink is 27 mN / m to 37 mN / m.

[0016] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0017] Figure 1 Printed images using the ink from Example 1 on a TIJ inkjet printer.

[0018] Figure 2 A printed image printed using ink from Comparative Example 1 on a TIJ inkjet printer.

[0019] Figure 3 Printed image using ink from Comparative Example 2 on a TIJ inkjet printer.

[0020] Figure 4 Printed images using ink from Comparative Example 3 on a TIJ inkjet printer.

[0021] Figure 5 Printed images using inks of Comparative Example 4 for TIJ inkjet printers.

[0022] Figure 6 Printed image using ink of Comparative 5 for TIJ inkjet printer.

[0023] Figure 7 Printed image using ink of Comparative Scale 6 for TIJ inkjet printer.

[0024] Figure 8 Printed image using ink of Comparative Example 7 for TIJ inkjet printer.

[0025] Figure 9 Printed image using ink of Comparative 8 for TIJ inkjet printer.

[0026] Figure 10 Printed image using ink of Comparative 9 for TIJ inkjet printer. Detailed Implementation

[0027] Current water-based inkjet inks are primarily developed for low-speed, intermittent inkjet printers. These printers operate at speeds of 20-30 m / min, producing small print runs (such as documents and photos), and have high tolerance for slow printing and response times, but strict requirements for image quality (such as color reproduction and detail sharpness). Therefore, the ink design emphasizes slow-drying characteristics, aiming to extend the ink's flow time on the paper surface, ensuring full color penetration and perfect detail blending. Simultaneously, moisture retention is achieved through optimized printer structure (such as moving the printhead under a protective cover to create a sealed space during standby), reducing printhead clogging caused by ink evaporation during standby. This design logic results in higher ink viscosity and a drying time of 2-10 seconds, which only meets the low-speed printing needs of inkjet printers and cannot meet the high-speed printing requirements of TIJ coding printers.

[0028] Inkjet printers print on cardboard boxes. In high-speed printing scenarios, the ink needs to have high fluidity to avoid ink supply interruptions that could lead to missing lines or other quality issues. Secondly, high-speed printing requires fast cardboard box transport, but the ink dries slowly, causing ink to flow on the cardboard surface during transport, affecting the final print quality. Furthermore, to avoid cardboard boxes taking up too much space, printed boxes need to be stacked promptly. When the ink dries slowly, contact between boxes can easily cause overprinting, ghosting, or adhesion contamination, resulting in blurred text and even failing to meet hygiene standards.

[0029] The core working principle of the TIJ inkjet printer is based on thermal foaming technology. An electric heating element heats the ink to over 300°C within 3 microseconds, forming microbubbles. These bubbles rapidly coalesce into larger bubbles, which quickly expand to their maximum size within the ink chamber. The resulting pressure forces a certain amount of ink droplets to overcome surface tension and be rapidly expelled from the printhead. This process places stringent requirements on ink performance: on the one hand, the ink must possess extremely high fluidity (viscosity 3-4 mPa·s) to support bubble formation and drive ejection within microseconds; on the other hand, the ink needs suitable surface tension to prevent excessive expansion and premature rupture at the printhead, which would lead to dripping and ink bleeding, affecting print quality. Simultaneously, to meet the standby requirements of several hours or even days in industrial production, the ink must possess long-lasting moisture retention, which contradicts the need for rapid ink drying.

[0030] Therefore, this invention analyzes the causes of ink clogging of printheads. Ink clogging of printheads is mainly related to solvent evaporation and solute crystallization. The type and content of organic solvents in ink determine its evaporation rate. To increase the drying speed of ink on the surface of cardboard boxes, it is necessary to accelerate the evaporation rate of ink. However, accelerating the evaporation rate means accelerating the solute crystallization rate. In order to avoid or delay solute crystallization, it is necessary to reduce the conductivity of ink.

[0031] Based on this, the purpose of the present invention is to provide a water-based pigment ink with extremely high fluidity (viscosity 3-4 mPa·s), suitable surface tension, instantaneous drying on the surface of a carton (<0.1 seconds), and low crystallization and clogging of the print head (low electrical conductivity).

[0032] Based on the above requirements, this invention re-screens and combines the solvents, humectants, and surfactants used in inks. Regarding solvents, conventional water-soluble organic solvents are insufficient to meet the dual requirements of low viscosity and high surface tension. For example, solvents such as glycerol, propylene glycol, and hydroxyethylpyrrolidone have high surface tension and viscosity; while solvents such as 2-pyrrolidone have relatively low viscosity and surface tension. When added to ink, to achieve the required surface tension, the amount of solvent added needs to be increased, but this easily leads to viscous ink with poor flowability; to achieve the required viscosity, the amount of solvent added needs to be reduced, but this easily leads to ink dripping from the printhead. Therefore, it is difficult to obtain ink that meets the surface tension and viscosity requirements using conventional solvents.

[0033] This invention discovers that the N-ethylated product of 2-pyrrolidone is N-ethylpyrrolidone (molecular formula C6H). 11N-ethylpyrrolidone (N-ethylpyrrolidone) has a low viscosity (3.5 mPa·s at 25°C) and moderate surface tension (36.5 mN / m at 20°C). At the same addition level, N-ethylpyrrolidone exhibits significantly better moisturizing properties than 2-pyrrolidone, and inks containing 2-pyrrolidone are prone to printhead clogging. Increasing the 2-pyrrolidone content results in a higher ink viscosity (greater than 4.0 Pa·s), exceeding the viscosity range of 3.0-4.0 Pa·s, thus leading to poor ink flow. In tests involving continuous printing for 2 hours at a high speed of 50 m / min, missing lines appeared in all patterns. Conversely, decreasing the 2-pyrrolidone content results in a lower ink viscosity (less than 3.0 Pa·s), also exceeding the viscosity range, causing ink to drip and leak in the cartridge, affecting print quality and even preventing printing altogether.

[0034] Furthermore, this invention also found that ethylene glycol has a low viscosity, comparable to 2-pyrrolidone, but its surface tension is higher than both N-ethylpyrrolidone and 2-pyrrolidone, and its conductivity is lower. Therefore, this invention attempted to blend ethylene glycol with N-ethylpyrrolidone, and found that compared to propylene glycol, the combination of ethylene glycol and N-ethylpyrrolidone can increase the surface tension of the ink, reduce the conductivity of the ink, and further reduce ink dripping, ink leakage, and ink crystallization leading to printhead clogging.

[0035] Currently, polysiloxane compounds and acetylenic diol surfactants are commonly used in inks. However, this invention has found that it is difficult to obtain inks that meet requirements, whether using one of them alone or in combination. Therefore, this invention attempts to use other surfactants as substitutes. Through screening, this invention found that the ink performance is superior when a wetting agent composed of acetylenic ethanol and acetylenic diol is combined with an acetylenic diol surfactant. The wetting agent composed of acetylenic ethanol and acetylenic diol can act as both a humectant and a surfactant, improving the ink's moisturizing properties and maintaining the ink's surface tension at 27-37 mN / m.

[0036] Based on this, the present invention provides a water-based pigment ink suitable for TIJ inkjet printers, the water-based pigment ink comprising the following components: pigment paste, N-ethylpyrrolidone, water-soluble organic solvent, acetylenol surfactant, acetylenol and acetylenol forming a wetting agent, preservative, and the balance being water.

[0037] Furthermore, pigment pastes can also be self-dispersible pigment pastes. Self-dispersible pigment pastes are pigments that can be dispersed in water without a dispersant. They are pigments that have undergone surface treatment to bind with at least one functional group selected from carboxyl, hydroxyl, and sulfonyl groups, or their salts. Surface treatment methods include, for example, vacuum plasma treatment, diazo coupling treatment, and oxidation treatment. Through these surface treatments, functional groups or molecules containing functional groups are grafted onto the pigment surface, thereby obtaining a self-dispersible pigment.

[0038] As the aforementioned pigment, the color paste is a self-dispersing color paste, which is a modified self-dispersing color paste containing sulfonic acid groups or phosphoric acid groups. Pigments selected from black pigments, preferably self-dispersing pigments containing sulfonic acid groups such as Pigment Black 7 and Pigment Black 11, are preferred.

[0039] The pigment concentration in the ink is preferably in the range of 5%-40% by weight of the total ink volume, more preferably in the range of 20%-40%.

[0040] N-ethylpyrrolidone plays an important role in promoting smoothness and acting as a solvent. N-ethylpyrrolidone is preferably 25%-35% by weight of the total ink volume, more preferably 25%-30%. The organic solvent is at least one or more alcohol organic solvents, which gives the ink good moisturizing properties and excellent printing smoothness.

[0041] As a solvent, examples include polyols. Specifically, it includes, but is not limited to, the following solvents: ethylene glycol, propylene glycol, 1,2-hexanediol, 1,2-propanetriol, 1,2-propanediol, diethylene glycol, triethylene glycol, sorbitol, etc. They can be used alone or in combination of two or more. The content of this solvent in the ink is 3%-10%, more preferably 3%-8%.

[0042] Surfactants include acetylenic diol surfactants, and wetting agents composed of acetylenic ethanol and acetylenic diol. Exemplarily, acetylenic diol surfactants include, but are not limited to, 2,4,7,9-tetramethyl-5-decyn-4,7-diol, 3,6-dimethyl-4-oct-3,6-diol, and 3,5-dimethyl-1-hexyn-3-ol. Specifically, the acetylenic diol surfactant may be selected from at least one of Surfymol 104, Surfymol 82, Surfymol 465, and Surfymol 485 (Air Products, Inc., USA). Preferably, the acetylenic diol surfactant is selected from at least one of Surfymol 465 and Surfymol 104. These surfactants help increase the printing smoothness of the ink. The content of the acetylenic diol surfactant is 0.1%-2% by mass of the water-based pigment ink, more preferably 0.1%-1%.

[0043] The HLB value of the wetting agent composed of acetylene ethanol and acetylene glycol is between 13 and 14. The content of the wetting agent composed of acetylene ethanol and acetylene glycol, by mass percentage, is 0.1% to 0.5% of the water-based pigment ink, more preferably 0.1% to 0.3%. In this invention, the wetting agent composed of acetylene ethanol and acetylene glycol is preferably selected from Nissin Chemical E1010.

[0044] The pigment black ink of the present invention may further contain a preservative, wherein the preservative is PROXEL-GXL.

[0045] The physicochemical parameters of the pigment black ink of this invention are within the acceptable range (i.e., surface tension of 27-37 mN / m, viscosity of 3.0-4.0 Pa·s, pH of 7-10, and conductivity <10 mS / cm). Excessive viscosity will result in poor ink flow and prone to line defects during printing, while insufficient viscosity will lead to ink dripping and bleeding. A pH that is too low or too high can affect the printhead's lifespan. When the ink surface tension is too low, the ink is prone to dripping and bleeding on the inkjet printer printhead, causing the printer to malfunction. Furthermore, the lower the ink conductivity, the better; ink with high conductivity is prone to crystallization, which can clog the printhead.

[0046] The water-based pigment ink of this invention keeps the printhead of the TIJ inkjet printer from drying out during long standby periods. After the printer has been open for 2 hours, printing can continue without clogging the printhead. At the same time, the ink has good flowability, good compatibility, and a longer printhead life than ordinary inks.

[0047] The present invention will be further described below through specific embodiments and comparative examples, but the present invention is not limited to these specific examples. All percentages of the components mentioned above and below in the present invention are weight percentages, and unless otherwise specified, they represent the percentage of that component by weight of the total pigment ink.

[0048] Example 1 Please refer to Table 1. This embodiment provides an aqueous pigment ink, which is composed of the following components by mass percentage: 36% pigment BK7 color paste, 4% ethylene glycol, 28% N-ethylpyrrolidone, 0.3% acetylenic glycol surfactant, 0.2% wetting agent composed of acetylenic ethanol and acetylenic glycol, 0.2% preservative, and the balance being water.

[0049] Table 1. Composition and content of water-based pigment inks in Examples 1 and Comparative Examples 1-6

[0050] In this embodiment, the preservative is PROXEL-GXL.

[0051] The wetting agent composed of acetylene ethanol and acetylene diol is selected from Nissin Chemical E1010, which is a product of the synthesis of acetylene ethanol and acetylene diol, and its molecular formula is as follows: .

[0052] The ethynyl ethanol and ethynyl glycol constitute the wetting agent with an average additional molar coefficient of 10 mol, an HLB value of 13-14, a water solubility greater than 3.0 wt%, and a 0.1 wt% aqueous solution of the wetting agent has a dynamic surface tension of 41 mN / m at 1 Hz and a dynamic surface tension of 44 mN / m at 10 Hz.

[0053] Tests showed that the physicochemical parameters of the water-based pigment ink of the present invention in Example 1 were all within the qualified range, with a surface tension of 27-37 mN / m, a viscosity of 3.0-4.0 Pa·s, a pH of 7-10, and an electrical conductivity of <10 ms / cm.

[0054] Comparative Example 1 Please refer to Table 1. The difference between Comparative Example 1 and Example 1 is that the weight percentage of N-ethylpyrrolidone is 20%.

[0055] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the weight percentage of N-ethylpyrrolidone is 40%.

[0056] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the weight percentage of ethylene glycol is 2%.

[0057] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that the weight percentage of ethylene glycol is 12%.

[0058] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that no acetylene ethanol and acetylene diol are added to form a wetting agent.

[0059] Comparative Example 6 The difference between Comparative Example 6 and Example 1 is that the weight percentage of acetylene ethanol and acetylene diol constituting the wetting agent is 0.6%.

[0060] Comparative Example 7 Referring to Table 2, the difference between Comparative Example 7 and Example 1 is that 2-pyrrolidone is used instead of N-ethylpyrrolidone.

[0061] Table 2. Composition and content of water-based pigment inks in Comparative Examples 7-9

[0062] Comparative Example 8 Referring to Table 2, the difference between Comparative Example 8 and Example 1 is that a polysiloxane compound is used instead of acetylene ethanol and acetylene diol to form the wetting agent.

[0063] Comparative Example 9 Referring to Table 2, the difference between Comparative Example 9 and Example 1 is that propylene glycol is used instead of ethylene glycol.

[0064] Test Example 1 Using the printhead of a TIJ inkjet printer, the inks prepared in Example 1 and Comparative Examples 1-9 were subjected to cap opening time tests, smoothness tests (continuous printing for 2 hours), and high-speed printing at 50 m / min (10,000 prints). The corresponding test results are shown in Table 3 and... Figures 1-10 As shown.

[0065] Table 3 Performance of water-based pigment inks in Examples 1 and Comparative Examples 1-9

[0066] Comparing Example 1 with Comparative Examples 1 and 2, it can be found that when the total ink volume of N-ethylpyrrolidone is less than 25%, the ink flow is poor, and after continuous printing for 2 hours at a high speed of 50 m / min, the test pattern shows missing lines; when the total ink volume of N-ethylpyrrolidone is greater than 35%, the ink viscosity increases, and after 10,000 high-speed printing tests at 50 m / min, the test pattern shows missing lines and stringing.

[0067] Comparing Example 1 with Comparative Examples 3 and 4, it can be found that when the weight of the organic solvent (ethylene glycol) is less than 4% of the total ink volume, the ink has poor moisture retention, and the test pattern shows missing lines after 2 hours of opening the cap; when the weight of the organic solvent (ethylene glycol) is greater than 4% of the total ink volume, the ink viscosity increases, and the test pattern shows missing lines after 10,000 high-speed printing tests at 50m / min.

[0068] Comparing Example 1 with Comparative Examples 5 and 6, it can be found that when the weight of the wetting agent composed of acetylene ethanol and acetylene glycol is less than 0.1% of the total ink volume, the ink wettability is poor, and missing lines appear in the test pattern after 2 hours of opening the lid; when the weight of the wetting agent composed of acetylene ethanol and acetylene glycol is greater than 0.5% of the total ink volume, the surface tension of the ink decreases, and the ink is prone to seeping and dripping in the ink cartridge, affecting the inkjet printer and preventing normal printing; missing lines appear in the test pattern after 2 hours of opening the lid.

[0069] Comparing Example 1 and Comparative Example 7, it can be found that without the addition of N-ethylpyrrolidone, when using a 2-pyrrolidone weight meter with a total ink volume of 28%, the pattern showed missing lines after 2 hours of testing with the cap open.

[0070] Comparing Example 1 and Comparative Example 8, it can be found that without adding acetylene ethanol and acetylene diol to form a wetting agent, and using polysiloxane compounds at a weight of 0.2% of the total ink volume, the ink flow is poor. After continuous printing for 2 hours and high-speed printing at 50 m / min, the test patterns all showed missing lines. After 2 hours of printing with the cap open, the test patterns also showed missing lines.

[0071] Comparing Example 1 and Comparative Example 9, it can be found that without the addition of ethylene glycol, using propylene glycol by weight to measure 4% of the total ink volume, the ink flow is poor, and at a high speed of 50m / min, the test patterns all show missing lines.

[0072] In summary, the water-based pigment ink provided by this invention has the following advantages: (1) By adjusting the type and content of organic solvent, the ink can be dried instantly on the surface of the carton (<0.1 seconds), which solves the problems of overprinting, ghosting, sticking pollution, and blurry text that easily occur when the existing water-based inkjet ink is directly applied to the high-speed printing scenario of the TIJ inkjet printer.

[0073] (2) By adjusting the composition and content of the ink, the physicochemical parameters of the ink are kept within the acceptable range, with a surface tension of 27-37 mN / m, a viscosity of 3.0-4.0 Pa·s, a pH of 7-10, and a conductivity of <10 mS / cm. The low viscosity and suitable surface tension result in good ink flow and compatibility, enabling the ink to adapt to high-speed printing scenarios of 50 m / min and reducing the likelihood of printing defects such as missing lines, ink dripping, and ink bleeding. The low conductivity ensures that the ink can remain in the printhead of the TIJ inkjet printer for a long time without drying out. After the inkjet printer is opened for 2 hours, printing can continue without clogging the printhead. The suitable pH value and conductivity help extend the life of the printhead.

[0074] (3) N-ethylpyrrolidone has a lower viscosity, moderate surface tension, and better moisturizing properties than 2-pyrrolidone; ethylene glycol has a lower viscosity and higher surface tension. When combined with N-ethylpyrrolidone, it can increase the surface tension of ink, reduce conductivity, and reduce ink dripping, ink leakage, and ink crystallization clogging of printheads.

[0075] (4) A wetting agent composed of acetylene ethanol and acetylene glycol is combined with an acetylene glycol surfactant. The wetting agent composed of acetylene ethanol and acetylene glycol can act as a humectant and surfactant, improving the ink's moisture retention and maintaining the ink's surface tension within a suitable range; the acetylene glycol surfactant helps increase the ink's printing smoothness.

[0076] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A water-based pigment ink, characterized in that, The water-based pigment ink comprises the following components: pigment paste, N-ethylpyrrolidone, water-soluble organic solvent, acetylenol surfactant, acetylenol ethanol and acetylenol forming a wetting agent, and the balance being water.

2. The water-based pigment ink according to claim 1, characterized in that, The N-ethylpyrrolidone is present in the water-based pigment ink at a weight percentage of 25%-35%.

3. The water-based pigment ink according to claim 2, characterized in that, The water-soluble organic solvent is selected from at least one of ethylene glycol, propylene glycol, 1,2-hexanediol, 1,2-propanetriol, 1,2-propanediol, diethylene glycol, triethylene glycol, and sorbitol.

4. The water-based pigment ink according to claim 3, characterized in that, The water-soluble organic solvent includes ethylene glycol, and the weight percentage of ethylene glycol in the water-based pigment ink is 3%-10%.

5. The water-based pigment ink according to claim 1, characterized in that, The wetting agent formed by acetylene ethanol and acetylene diol is a synthetic reactant of acetylene ethanol and acetylene diol, and its molecular formula is as follows: 。 6. The water-based pigment ink according to claim 5, characterized in that, The HLB value of the wetting agent composed of acetylene ethanol and acetylene glycol is 13-14, and the weight percentage of the wetting agent composed of acetylene ethanol and acetylene glycol in the water-based pigment ink is 0.1%-0.5%.

7. The water-based pigment ink according to claim 1, characterized in that, The weight percentage of the acetylenic diol surfactant in the aqueous pigment ink is 0.1%-2%.

8. The water-based pigment ink according to claim 1, characterized in that, The pigment ink also includes a preservative, which accounts for 0.1% to 1% of the total mass of the pigment ink.

9. The water-based pigment ink according to any one of claims 1-8, characterized in that, The viscosity of the water-based pigment ink is 3.0 Pa·s to 4.0 Pa·s.

10. The water-based pigment ink according to claim 9, characterized in that, The surface tension of the water-based pigment ink is 27mN / m-37mN / m.

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