Aqueous yellow polymer ink and method for its preparation

Abstract

The present application relates to the technical field of digital inkjet ink, in particular to a water-based yellow polymer ink and a preparation method thereof. The raw materials of the water-based yellow polymer ink include a yellow ceramic pigment, a water-soluble polyacrylic acid polymer, a thickening agent, a surface tension mixture, and water. Specifically, 0.2-1.0 mg of the water-soluble polyacrylic acid polymer is contained in each cubic meter of the water-based yellow polymer ink, and 13-16% by volume of the yellow ceramic pigment is contained in each 100 parts of the water-based yellow polymer ink. In addition, 0.01-15% by mass of the thickening agent and 0.01-0.1% by mass of the surface tension mixture are contained in each 100 parts of the water-based yellow polymer ink. The ink does not contain organic solvents and volatile organic compounds, and still has good dispersibility and inkjet properties. The harm caused by the organic solvents and volatile organic compounds in the ink is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of digital inkjet ink, in particular to a water-based yellow polymer ink and a preparation method thereof. BACKGROUND

[0002] Digital inkjet printing is a technology based on transmitting digitalized pattern data to an inkjet printer and jetting ink droplets to print a pattern directly on a substrate. Compared with traditional graphic printing technology, the digital inkjet printing process can easily create or customize printed images, and there is no need for contact between the substrate and the print head, so various materials and objects with complex shapes can be used as substrates. In addition, since the digital inkjet printing method based on drop-on-demand is used to jet ink only to the desired position, this printing technology can achieve high ink efficiency.

[0003] Due to these advantages, ceramic inkjet printing has become the preferred technology in the tile decoration industry in the past decade. However, despite its success, the industry is recently under pressure from environmental issues such as global warming and air pollution. Since most of the inks used in digital inkjet printing are based on organic solvents and contain volatile organic compounds (VOCs) to ensure their dispersion stability and printability, such inks have the following disadvantages: 1) affect human health, which can cause operating personnel to face occupational hazards, and long-term or repeated exposure to high levels of VOCs can have serious health effects on the central nervous system, liver or kidneys; 2) air pollution and environmental impact, VOCs released into the atmosphere can react with other pollutants and sunlight to form ozone, which has adverse effects on air quality and human health. When they are released into the soil or water, they can pollute these resources and pose a threat to plants, animals and aquatic ecosystems. In addition, VOC emissions also contribute to the formation of greenhouse gases, exacerbating climate change.

[0004] Therefore, it is necessary to develop environmentally friendly and functional ceramic inks to replace VOC-containing organic solvent-based inkjet printing inks.

[0005] In view of this, the present application is proposed. SUMMARY

[0006] The present application aims to provide a water-based yellow polymer ink and a preparation method thereof. The ink provided by the present application does not contain organic solvents and volatile organic compounds, and the ink still has good dispersibility and inkjet properties, which improves the hazards caused by the presence of organic solvents and volatile organic compounds in the ink.

[0007] The present application is implemented as follows:

[0008] In a first aspect, the present application provides an aqueous yellow polymer ink, which is prepared from a yellow ceramic pigment, a water-soluble polyacrylic acid polymer, a thickening agent, a surface tension mixture and water, wherein the water-soluble polyacrylic acid polymer is contained in an amount of 0.2-1.0 mg per cubic meter of the aqueous yellow polymer ink, the yellow ceramic pigment is contained in an amount of 13-16% by volume per 100 parts of the aqueous yellow polymer ink, the thickening agent is contained in an amount of 0.01-15% by mass per 100 parts of the aqueous yellow polymer ink, and the surface tension mixture is contained in an amount of 0.01-0.1% by mass per 100 parts of the aqueous yellow polymer ink.

[0009] In an optional embodiment, the thickening agent is selected from a polyol polymer, preferably a polyethylene glycol.

[0010] The surface tension mixture is selected from a polysilane.

[0011] In an optional embodiment, the water-soluble polyacrylic acid polymer is contained in an amount of 0.2-1.0 mg per cubic meter of the aqueous yellow polymer ink, the yellow ceramic pigment is contained in an amount of 13-16% by volume per 100 parts of the aqueous yellow polymer ink, the polyethylene glycol is contained in an amount of 0.01-15% by mass per 100 parts of the aqueous yellow polymer ink, and the polysilane is contained in an amount of 0.01-0.1% by mass per 100 parts of the aqueous yellow polymer ink.

[0012] In an optional embodiment, the aqueous acrylic acid polymer is a polymer with polyacrylic acid as a main chain and polyethylene glycol methyl methacrylate as a side chain.

[0013] The solid content of the aqueous acrylic acid polymer is 10-30%.

[0014] In an optional embodiment, the yellow ceramic pigment is selected from Pr-doped ZrSiO4.

[0015] In an optional embodiment, the Pr-doped ZrSiO4 is prepared by wet mixing a base material, a mineralizer and a solvent, and then drying, calcining and micronizing, wherein the base material is selected from silicon dioxide, zirconium dioxide and praseodymium oxide.

[0016] In an optional embodiment, the silicon dioxide is contained in an amount of 30-40% by mass, the zirconium dioxide is contained in an amount of 55-65% by mass, and the praseodymium oxide is contained in an amount of 2-7% by mass in the base material.

[0017] The mineralizer is contained in an amount of 2-4% by mass of the base material.

[0018] In an optional embodiment, the mineralizer is selected from sodium fluoride.

[0019] The drying temperature is 75-85℃, and the calcination temperature is 1000-1200℃.

[0020] In an optional embodiment, the aqueous acrylic polymer is synthesized from polyacrylic acid, ammonium persulfate, hydroquinone monomethyl ether and polyethylene glycol methyl methacrylate.

[0021] In a second aspect, the application provides a preparation method of the aqueous yellow polymer ink of the foregoing embodiments, comprising: mixing a yellow ceramic pigment, an aqueous polyacrylic acid polymer, a thickening agent, a surface tension mixing agent and water in proportion.

[0022] The application has the following beneficial effects: the yellow ceramic pigment, the aqueous polyacrylic acid polymer, the thickening agent and the surface tension mixing agent are mixed in a specific proportion in the embodiments of the application, so that the prepared aqueous yellow polymer ink has good dispersibility and jet printing property even without using organic solvents and volatile compounds, and can be widely used in digital inkjet printing. At the same time, the hazards caused by the organic solvents and volatile compounds in the existing digital inkjet printing ink are avoided. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0024] Figure 1 The detection result graph provided for detection example 1 of the application;

[0025] Figures 2-3 The detection result graph provided for detection example 2 of the application;

[0026] Figure 4 The detection result graph provided for detection example 3 of the application;

[0027] Figure 5 The X-ray and FE-SEM electron microscope result graph provided for detection example 4 of the application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the application more clear, the technical solutions in the embodiments of the application will be described clearly and completely below. The specific conditions not mentioned in the embodiments are carried out according to the conventional conditions or the conditions suggested by the manufacturers. The reagents or instruments not mentioned by the manufacturers are all conventional products that can be obtained by market purchase.

[0029] The water-based yellow polymer ink of the present application comprises yellow ceramic pigment, water-soluble polyacrylic acid polymer, thickening agent, surface tension mixture and water. The water-soluble polyacrylic acid polymer is 0.2-1.0 mg per cubic meter of the water-based yellow polymer ink. The yellow ceramic pigment is 13-16% by volume per 100 parts of the water-based yellow polymer ink. The thickening agent is 0.01-15% by mass per 100 parts of the water-based yellow polymer ink. The surface tension mixture is 0.01-0.1% by mass per 100 parts of the water-based yellow polymer ink.

[0030] The thickening agent is selected from polyol polymers, preferably polyethylene glycol. The polyethylene glycol and other polyol polymers are commercially available raw materials, such as those available from Aibisheng (Shanghai) Biotechnology Co., Ltd.

[0031] The surface tension mixture is selected from polysilane. Polysilane is also a commercially available raw material, such as those available from Shanghai Yuanye Bio-Technology Co., Ltd.

[0032] Therefore, the water-soluble polyacrylic acid polymer is 0.2-1.0 mg per cubic meter of the water-based yellow polymer ink. The yellow ceramic pigment is 13-16% by volume per 100 parts of the water-based yellow polymer ink. The polyethylene glycol is 0.01-15% by mass per 100 parts of the water-based yellow polymer ink. The polysilane is 0.01-0.1% by mass per 100 parts of the water-based yellow polymer ink.

[0033] For example, the water-soluble polyacrylic acid polymer is 0.2 mg, 0.3 mg, 0.4 mg, 0.5 mg, 0.6 mg, 0.7 mg, 0.8 mg, 0.9 mg and 1.0 mg, or any value between 0.2-1.0 mg or a range formed by any two values.

[0034] The volume fraction of the yellow ceramic pigment is 13%, 14%, 15% and 16%, or any value between 13-16% or a range formed by any two values.

[0035] The mass fraction of the polyethylene glycol is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.5%, 1%, 5%, 10% and 15%, or any value between 0.01-15% or a range formed by any two values.

[0036] The mass fraction of polysilane is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1% or any value or range formed by any two values between 0.01% and 0.1%.

[0037] In the embodiment of the present application, the crystal structure of the yellow ceramic pigment is Pr-doped ZrSiO4. ZrSiO4 has a main structural unit of edge-shared SiO4 tetrahedron and ZrO8 trigonal dodecahedron, containing an empty octahedral void. The yellow ceramic pigment can be self-made or purchased, for example, from Shandong Suihua Biotechnology Co., Ltd.

[0038] The embodiment of the present application also provides a preparation process of the above-mentioned yellow ceramic pigment, and the synthesis process of ZrSiO4 is as follows:

[0039] SiO2+4NaF→SiF4(g)+2Na2O

[0040] SiF4→Si 4+ +4e - +2F2

[0041] Si 4+ +4e - +ZrO2+O2→ZrSiO4

[0042] Specifically, the base material, mineralizer, alumina ball and solvent (such as ethanol) are wet mixed together for 3 hours to form a mixed powder, and then the mixed powder is dried at 75-85°C, and then calcined at 1000-1200°C for 1-2 hours in an oxidizing environment (oxygen-containing atmosphere). Then, the obtained yellow ceramic pigment is micronized using a bead mill, and the particle size of the powder obtained after micronization is less than one-fiftieth of the diameter of the nozzle of inkjet printing, and the average particle size is generally less than 300 nm to prevent the nozzle of the inkjet printing head from being blocked.

[0043] The mineralizer is selected from NaF, and the amount of the mineralizer is 2-4% of the amount of the base material.

[0044] The amount of the silicon dioxide in the base material is 30-40% by mass percentage, the amount of the zirconium dioxide is 55-65% by mass percentage, and the amount of the praseodymium oxide is 2-7% by mass percentage. The total amount of the silicon dioxide, the zirconium dioxide and the praseodymium oxide is 100%.

[0045] The solid content of the aqueous acrylic polymer is 10-30%.

[0046] The water-based acrylic polymer is a polymer with polyacrylic acid as the main chain and polyethylene glycol methyl methacrylate as the side chain. Specifically, it is synthesized from polyacrylic acid, ammonium persulfate, hydroquinone monomethyl ether and polyethylene glycol methyl methacrylate.

[0047] The embodiment of the present application selects polyacrylic acid as the main chain to ensure electrostatic repulsion and selects polyethylene glycol methyl methacrylate as the side chain to provide steric hindrance. When the effects of electrostatic repulsion and steric hindrance are combined, high dispersion stability of pigment particles in the water-based ceramic ink can be achieved.

[0048] Further, the water-based acrylic polymer can be self-made or purchased as a finished product, for example, from Beijing Zhisheng Weihua Chemical Co., Ltd.

[0049] The embodiment provides an example to illustrate the preparation steps as follows: polyacrylic acid and polyethylene glycol methyl methacrylate (molar ratio = 1.5-2.0) are mixed with hydroquinone monomethyl ether (0.5-1.0% of the total weight of monomers) in deionized water. After complete dissolution, the polyacrylic acid solution and ammonium persulfate (0.5-1.0% of the total weight of monomers) are added dropwise into the deionized water in the reactor to form a mixture. The reactor is equipped with a reflux condenser, a feed port and an air inlet tube. The mixture is stirred and heated at 75-95℃ for 4-6 hours. Then, the reaction solution is cooled to room temperature, and the pH value is adjusted to 5-6 with NaOH (40-60% by weight aqueous solution). Finally, a brown transparent polymer surfactant is obtained.

[0050] It should be noted that the yellow ceramic pigment and the preparation method of the water-based polyacrylic polymer provided by the above embodiment of the present application are only examples of the embodiment of the present application.

[0051] The embodiment of the present application prevents the agglomeration of yellow ceramic pigment particles in the ink by using a water-based polyacrylic polymer, thereby preventing the nozzle from being blocked during inkjet printing. It can also make the yellow ceramic pigment more uniformly distributed and improve the inkjet printing performance. The addition of thickening agent and surface tension mixture can adjust the rheological properties of the ink and further improve the performance of the ink.

[0052] In a second aspect, the present application provides a preparation method of the water-based yellow polymer ink of the foregoing embodiment, comprising: mixing the yellow ceramic pigment, the water-based polyacrylic polymer, the thickening agent, the surface tension mixture and water in proportion.

[0053] The features and properties of the present application are further described in detail below in conjunction with the embodiments.

[0054] The instruments used for the detection are as follows: viscosity measurement uses a rotational rheometer (HAAKE MARS III, ThermoFisher Scientific, USA), surface tension uses a surface tension analyzer (DST-60, Surface ElectroOptics, Korea), sedimentation and dispersibility uses a Turbiscan (Turbiscan LAB, Formulaction, France), in addition, hydrodynamic radius and surface charge uses a particle size analyzer (VASCO, Cordouan, France) and a Zeta potential analyzer (ELS-Z, Otsuka Electronics, Japan).

[0055] Example 1

[0056] The embodiment of the present application provides a kind of aqueous yellow polymer ink, it includes volume fraction 16% yellow ceramic pigment, 0.5mg / m 2 Aqueous polyacrylic acid polymer (molecular weight 950), mass fraction 12% polyethylene glycol (molecular weight 1800), mass fraction 0.08% polysilane and water.

[0057] Wherein, polyethylene glycol (molecular weight 1800) is purchased from Aibisheng (Shanghai) Biotechnology Co., Ltd. Polysilane is purchased from Shanghai Yuan Ye Biotechnology Co., Ltd.

[0058] The preparation of aqueous acrylic acid polymer is as follows:

[0059] Polyacrylic acid and polyethylene glycol methyl methacrylate (molar ratio = 2.0) are mixed with hydroquinone monomethyl ether (1.0% of the total weight of monomers) in deionized water. After complete dissolution, polyacrylic acid solution and ammonium persulfate (0.5% of the total weight of monomers) are added dropwise to deionized water in the reactor to form a mixture. The reactor is equipped with a reflux condenser, a feed port and an air inlet tube. The mixture is stirred and heated at 85°C for 5 hours. After that, the reaction solution is cooled to room temperature, and the pH value is adjusted to 5.5 with NaOH (50% by weight aqueous solution). Finally, a brown transparent polymer surfactant (20% by weight of solid content in aqueous solution) is obtained.

[0060] The preparation of yellow ceramic pigment is as follows:

[0061] The base material (60% by weight ZrO2, 35% by weight SiO2, 5% by weight Pr6O 11) and mineralizer (3% NaF by weight added to the mixture of base materials) were wet mixed with alumina balls and ethanol for 3 hours, after which the mixed powder was dried in an oven at 80°C and then sintered at 1100°C for 1 hour under an oxidizing environment. The resulting yellow ceramic pigment was then micronized using a bead mill.

[0062] Example 2

[0063] The embodiment of the present application provides a water-based yellow polymer ink, which comprises a volume fraction of 15% yellow ceramic pigment, 0.35mg / m 2 a water-based polyacrylic acid polymer, a mass fraction of 12% polyethylene glycol (molecular weight 1800), a mass fraction of 0.08% polysilane and water.

[0064] The polyethylene glycol (molecular weight 1800) is purchased from Aibisheng (Shanghai) Biotechnology Co., Ltd. The polysilane is purchased from Shanghai Yuanye Biotechnology Co., Ltd. The yellow ceramic pigment is purchased from Shandong Suihua Biotechnology Co., Ltd.

[0065] Example 3

[0066] The embodiment of the present application provides a water-based yellow polymer ink, which comprises a volume fraction of 13% yellow ceramic pigment, 0.35mg / m 2 a water-based polyacrylic acid polymer, a mass fraction of 10% polyethylene glycol (molecular weight 1800), a mass fraction of 0.08% polysilane and water.

[0067] The polyethylene glycol (molecular weight 1800) is purchased from Aibisheng (Shanghai) Biotechnology Co., Ltd. The polysilane is purchased from Shanghai Yuanye Biotechnology Co., Ltd. The yellow ceramic pigment is purchased from Shandong Suihua Biotechnology Co., Ltd.

[0068] Detection example

[0069] The viscosity depends on the interaction between particles, specifically, weak interaction leads to low viscosity, and strong interaction leads to high viscosity, and the measurement of viscosity also reflects the dispersion of the ink, that is, the lower the viscosity, the more dispersed the ink, and the dispersion is uniform and stable.

[0070] Therefore, sodium dodecyl sulfate (SDS) (purchased from Shenzhen Zhenqiang Biotechnology Co., Ltd.), polyacrylic acid (purchased from Beijing Zhisheng Weihua Chemical Co., Ltd.) and the water-based polyacrylic acid polymer provided in the embodiment 1 of the present application are respectively used as surface active agents, and inks are respectively prepared in different adding concentration gradients and the viscosity of the inks is measured. The content of yellow ceramic powder, polyethylene glycol and polysilane in the ink is the same as that in the embodiment 1.

[0071] The results are shown in Figure 1 . According to Figure 1It can be seen that the water-based polypropylene polymer in the embodiment of the application can significantly reduce the viscosity of the ink, and the water-based polypropylene polymer can be fully adsorbed to the surface of the ceramic particles, thereby effectively hindering the interaction between the ceramic particles. In particular, when the content of the water-based polypropylene polymer is 0.5 mg / m 2 , the viscosity value of the ink is 1.15 mPa.s, and the viscosity is optimal at this time.

[0072] Test Example 2

[0073] The water-soluble polyacrylic acid polymer in Example 1 is replaced with polyacrylic acid (purchased from Hubei Xindesheng Material Technology Co., Ltd.), and no water-soluble polyacrylic acid polymer is used, and then the zeta potential, hydrodynamic radius and sedimentation rate of the three inks are tested.

[0074] The results are shown in Figure 2 and Figure 3 . It can be seen from Figure 2 that, in the absence of a surfactant, the zeta potential of the water-based polymer ink is -18.7 mV, and after the addition of polyacrylic acid and water-based polyacrylic acid polymer, the zeta potential is -39.4 mV and -42.1 mV, thereby indicating that the dispersion stability of the ink is improved. Generally, the zeta potential between 0 and -30 mV is considered to represent low dispersion stability, and more than -30 mV indicates good dispersion stability. In addition, in the absence of a surfactant, the hydrodynamic radius of the water-based polymer ink is 265 nm, and in the presence of polyacrylic acid and water-based polyacrylic acid polymer, the hydrodynamic radius is 315 nm and 365 nm, respectively.

[0075] It can be seen from Figure 3 that the sedimentation rates of the samples containing no surfactant and containing polyacrylic acid are 0.78 mm / h and 0.67 mm / h, respectively, and the sedimentation rate of the ink sample using the water-based polyacrylic acid polymer as a surfactant is 0.29 mm / h, which is 56.7% slower than that of the ink sample containing polyacrylic acid. Further, it is further illustrated that the dispersion stability of the water-based yellow polymer ink provided by the embodiment of the application is obviously improved.

[0076] Test Example 3

[0077] The yellow ceramic pigment in Example 1 is changed to pigment yellow 81 yellow pigment (purchased from Hubei Qifei Pharmaceutical Chemical Co., Ltd.), and the ink jetting form and printability thereof are tested.

[0078] The results are shown in Figure 4 , Figure 4 , which shows the comparison of the ink jetting form and printability of different yellow pigment inks, wherein a is the yellow ceramic pigment used in the embodiment of the application, and b is pigment yellow 81. According to Figure 4It can be seen that long ink drop tail and satellite ink drop are observed for Pigment Yellow 81, and drop leakage is also found after the initial ink drop is ejected, and the printing dot area size is uneven, which affects the printing quality.

[0079] Detection Example 4

[0080] The yellow ceramic pigment prepared in Example 1 is subjected to X-ray and SEM electron scanning detection, and the results are shown in Table 1. Figure 5 wherein, Figure 5 In Table 1, a represents the X-ray diffraction (XRD) spectrum of the yellow ceramic pigment; b represents the electron field emission scanning electron microscope (FE-SEM) image. Figure 5 It can be seen that the main phase of the yellow ceramic pigment of the present application is ZrSiO4. Figure 5 It can be seen that the yellow ceramic pigment has an irregular granular shape, with rough edges, and the particle size of the pigment is about 50-900 nm, the D90 particle size is 647 nm, and the average particle size is 289 nm. This shape is due to the decomposition of the ceramic particles by high mechanical energy during the micronization process.

[0081] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An aqueous yellow polymeric ink, characterized by, The raw materials are yellow ceramic pigment, water-soluble polyacrylic acid polymer, thickening agent, surface tension mixing agent and water, The water-soluble polyacrylic acid polymer is 0.2-1.0 mg per cubic meter of the water-based yellow polymer ink, the yellow ceramic pigment is 13-16% by volume fraction per 100 parts of the water-based yellow polymer ink, the thickening agent is 0.01-15% by mass fraction per 100 parts of the water-based yellow polymer ink, and the surface tension mixing agent is 0.01-0.1% by mass fraction per 100 parts of the water-based yellow polymer ink; the water-based acrylic acid polymer is a polymer with polyacrylic acid as the main chain and polyethylene glycol methyl methacrylate as the side chain; The thickening agent is polyethylene glycol, and the surface tension mixing agent is selected from polysilane; The average particle size of the yellow ceramic pigment is less than 300 nm; The yellow ceramic pigment is selected from Pr-doped ZrSiO4, The preparation process of the Pr-doped ZrSiO4 is as follows: wet mixing of base material, mineralizer and solvent, and then drying, calcining and micronization, wherein the base material is selected from silicon dioxide, zirconium dioxide and praseodymium oxide.

2. The water-based yellow polymer ink according to claim 1, characterized in that, The solid content of the water-based acrylic acid polymer is 10-30%.

3. The aqueous yellow polymeric ink according to claim 1, characterized in that, The amount of the silicon dioxide in the base material is 30-40% by mass percentage, the amount of the zirconium dioxide is 55-65% by mass percentage, and the amount of the praseodymium oxide is 2-7% by mass percentage; The amount of the mineralizer is 2-4% of the amount of the base material.

4. The aqueous yellow polymeric ink according to claim 1, characterized in that, The mineralizer is selected from sodium fluoride; The drying temperature is 75-85°C, and the calcining temperature is 1000-1200°C.

5. The aqueous yellow polymeric ink according to claim 2, characterized in that, The water-based acrylic acid polymer is synthesized from polyacrylic acid, ammonium persulfate, hydroquinone monomethyl ether and polyethylene glycol methyl methacrylate.

6. A method of producing the aqueous yellow polymeric ink according to claim 1, characterized by, Comprising: Mixing yellow ceramic pigment, water-soluble polyacrylic acid polymer, thickening agent, surface tension mixing agent and water in proportion.

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