Plant-based aqueous ink and method of making the same

Abstract

The application discloses a plant-based water-based ink and a preparation method thereof, and relates to the field of water-based ink. In the preparation of the plant-based water-based ink, microcrystalline cellulose is aldehyde-based, then grafted with 2-mercaptoethylamine, and then bonded with nano-silver to obtain modified cellulose; octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethyl silane and pentamethyldisiloxane are reacted, then grafted with hydrazine hydrate to obtain modified silicone oil; polybutylene adipate, castor oil, isophorone diisocyanate and the modified silicone oil are uniformly mixed to obtain modified polyurethane emulsion; amino malonic acid and 3,5-di-tert-butyl-4-hydroxybenzaldehyde are reacted, then mixed with carbon black powder and 1,5-dihydroxy-3-pentanone to obtain modified carbon black; the modified polyurethane emulsion, color paste, leveling agent and the modified cellulose are uniformly mixed to obtain the plant-based water-based ink. The plant-based water-based ink prepared by the application has excellent antistatic, wear-resistant and durable properties.

Description

TECHNICAL FIELD

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

[0002] With the rapid development of China's economy, the stationery market is booming, and the market demand for markers, which are widely used in daily life, is increasing year by year. Markers are mainly used for drawing, marking, signing, etc., and have high performance requirements for ink, such as quick-drying, wear-resistant, bright color, etc. Traditional marker ink is mostly solvent-based polyurethane ink, which has good performance but has environmental problems and causes harm to the environment and human health. Therefore, the present application prepares a plant-based water-based ink with excellent wear resistance. SUMMARY

[0003] The present application aims to provide a plant-based water-based ink and a preparation method thereof to solve the problems in the prior art.

[0004] In order to solve the above technical problems, the present application provides the following technical scheme:

[0005] A plant-based water-based ink is obtained by mixing modified polyurethane emulsion, color paste, leveling agent and modified cellulose.

[0006] As an optimization, the leveling agent is model Digo 450 from Dongguan Hongrui Chemical Co., Ltd.

[0007] As an optimization, the color paste is obtained by mixing carbon black powder, 1,5-dihydroxy-3-pentanone after the reaction of aminopropionic acid and 3,5-di-tert-butyl-4-hydroxybenzaldehyde, and then grinding and preparing.

[0008] As an optimization, the carbon black powder is model BC6190 from Tianjin Baoci Chemical Co., Ltd.

[0009] As an optimization, the modified polyurethane emulsion is obtained by mixing polybutylene adipate, castor oil, isophorone diisocyanate and modified silicone oil.

[0010] As an optimization, the polybutylene adipate is model PBA1000 from Xuzhou Yihuiyang New Material Co., Ltd.

[0011] As an optimization, the castor oil is from Shandong Yunxin New Material Technology Co., Ltd.

[0012] As an optimization, the modified cellulose is obtained by grafting 2-mercaptoethylamine after aldehyde group modification of microcrystalline cellulose and then bonding with nano-silver.

[0013] As optimization, the microcrystalline cellulose is CP2020 from Shanxi Jinyang Pharmaceutical Auxiliary Co., Ltd.

[0014] As optimization, the modified silicone oil is prepared by reacting octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethyl silane and pentamethyldisiloxane, and then grafting hydrazine hydrate.

[0015] A preparation method of a plant-based water-based ink, comprising the following preparation steps:

[0016] (1) mixing microcrystalline cellulose and deionized water in a mass ratio of 1:(55-65) uniformly, adding

[0017] 0.09-0.11 mol / L hydrochloric acid solution to adjust pH to 2-4, stirring at 25-35℃ and 300-400 rpm in the dark for 10-20 min, adding sodium periodate in an amount of 0.9-1.1 times the mass of the microcrystalline cellulose, continuing to stir in the dark for 7-9 h, filtering, washing with deionized water for 3-5 times, and freeze-drying for 11-13 h to obtain aldehyde-modified cellulose; mixing the aldehyde-modified cellulose, 2-mercaptoethylamine and anhydrous ethanol in a mass ratio of 1:(2-4):(15-25) uniformly, stirring at 45-55℃ and 300-400 rpm for 4-6 h, filtering after natural cooling to room temperature, washing with deionized water for 3-5 times, and drying at 55-65℃ for 7-9 h to obtain pre-modified cellulose; ultrasonic oscillation of the pre-modified cellulose and a nano-silver ethanol dispersion liquid with a mass fraction of 35%-45% at 55-65℃ for 25-35 min, filtering, washing with anhydrous ethanol for 3-5 times, and drying at 60-70℃ for 8-10 h to obtain modified cellulose;

[0018] (2) mixing octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethyl silane and tetramethylammonium hydroxide silanol salt in a mass ratio of 1:(1.3-1.5):(0.01-0.03) uniformly, stirring at 85-95℃ and 100-200 rpm in a nitrogen atmosphere for 2-3 h, adding pentamethyldisiloxane in an amount of 0.1-0.3 times the mass of the octamethylcyclotetrasiloxane, increasing the temperature to 95-105℃ and continuing to stir for 7-9 h, increasing the temperature to 130-140℃ at a rate of 10-20℃ / min and continuing to stir for 40-50 min, and distilling at 0.1-0.3 MPa for 1-2 h to obtain pre-modified silicone oil; mixing the pre-modified silicone oil, hydrazine hydrate and ethanol in a mass ratio of 1:(1-2):(6-7) uniformly, stirring at 20-30℃ and 300-400 rpm for 25-35 min, and distilling under reduced pressure to obtain modified silicone oil;

[0019] (3) Mix polybutylene adipate and castor oil at a mass ratio of 1:(0.4-0.5), add isophorone diisocyanate, and stir for 2-4 hours at 85-95°C and 100-300 rpm under a nitrogen atmosphere. Add dimethylolpropionic acid at 0.07-0.08 times the mass of polybutylene adipate, cool to 75-85°C and continue stirring for 55-65 minutes. Add dibutyl dilaurate at 0.01-0.03 times the mass of polybutylene adipate, add acetone to adjust the viscosity, and cool to 60-70°C. Add 0.01–0.05 times the mass of polybutylene adipate modified silicone oil and 0.002–0.004 times the mass of polybutylene adipate chloroplatinic acid, continue stirring for 3–5 hours, rotary evaporate at 35–45°C for 30–50 minutes, add 0.056–0.058 times the mass of polybutylene adipate triethylamine to neutralize for 30–40 minutes, add 3–4 times the mass of polybutylene adipate deionized water, stir at 600–800 rpm for 30–40 minutes to obtain modified polyurethane emulsion;

[0020] (4) Mix aminomalonic acid, 3,5-di-tert-butyl-4-hydroxybenzaldehyde and anhydrous ethanol at a mass ratio of 1:(1-3):(8-9), stir at 45-55°C and 100-200 rpm for 4-6 h in a nitrogen atmosphere, and then rotary evaporate to obtain an antioxidant; mix carbon black powder, antioxidant, 1,5-dihydroxy-3-pentanone and toluene at a mass ratio of 1:(1.1-1.3):(0.3-0.5):(9-11), stir at 75-85°C and 200-400 rpm for 2-4 h in a nitrogen atmosphere, filter, wash 3-5 times with anhydrous ethanol, and dry at 60-70°C for 8-10 h to obtain modified carbon black;

[0021] (5) Grind the modified carbon black in a ball mill for 7-9 hours, mix it with anhydrous ethanol at a mass ratio of 1:(8-10), and ultrasonically disperse it for 1-3 hours to obtain a color paste; mix the modified polyurethane emulsion, color paste, leveling agent and modified cellulose at a mass ratio of 1:(0.3-0.5):(0.04-0.06):(0.03-0.05), and disperse it at 1500-2500 r / min for 25-35 min to obtain a plant-based water-based ink.

[0022] As an optimization, the reaction equation for the modified cellulose in step (1) is:

[0023]

[0024] As an optimization, the reaction equation for the modified silicone oil in step (2) is:

[0025]

[0026] As an optimization, the molar amount of isophorone diisocyanate added in step (3) is 0.49 times the sum of the molar amounts of hydroxyl groups contained in polybutylene adipate, castor oil and dimethylolpropionic acid.

[0027] As an optimization, the reaction equation for the modified polyurethane emulsion in step (3) is:

[0028]

[0029] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0030] In preparing plant-based water-based inks, this invention involves aldehyde-modifying microcrystalline cellulose, grafting it with 2-mercaptoethylamine, and then bonding it with nano-silver to obtain modified cellulose; reacting octamethylcyclotetrasiloxane, 2-methyl ester-ethyl dimethoxymethylsilane, and pentamethyldisiloxane, followed by grafting with hydrazine hydrate to obtain modified silicone oil; mixing polybutylene adipate, castor oil, isophorone diisocyanate, and modified silicone oil to obtain a modified polyurethane emulsion; reacting aminomalonic acid and 3,5-di-tert-butyl-4-hydroxybenzaldehyde, followed by mixing with carbon black powder and 1,5-dihydroxy-3-pentanone to obtain modified carbon black; then formulating the modified carbon black to obtain a color paste, which is then mixed with the modified polyurethane emulsion, a leveling agent, and modified cellulose to obtain the plant-based water-based ink.

[0031] First, modified cellulose is prepared by aldehyde-modifying microcrystalline cellulose, grafting 2-mercaptoethylamine, and then bonding it with nano-silver. Modified silicone oil is prepared by reacting octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethylsilane, and pentamethyldisiloxane, followed by grafting hydrazine hydrate. 2-Mercaptoethylamine is grafted onto microcrystalline cellulose via Schiff base reaction, utilizing the strong S-Ag bond to generate chemical adsorption on the nano-silver surface, forming an electron transport pathway and improving the antistatic properties of the plant-based water-based ink. Flexible organosilicon long chains are grafted onto the polyurethane backbone via hydrosilylation, reducing the coefficient of friction and improving the abrasion resistance of the plant-based water-based ink. Simultaneously, hydrazide groups are formed on the siloxane long chains, forming a cross-linking network with the carbonyl groups on the modified carbon black, further improving the abrasion resistance of the plant-based water-based ink.

[0032] Secondly, a modified polyurethane emulsion was obtained by mixing polybutylene adipate, castor oil, isophorone diisocyanate, and modified silicone oil. A modified carbon black was obtained by reacting aminomalonic acid and 3,5-di-tert-butyl-4-hydroxybenzaldehyde with carbon black powder and 1,5-dihydroxy-3-pentanone. The modified carbon black was then formulated into a color paste, which was mixed with the modified polyurethane emulsion, a leveling agent, and modified cellulose to obtain a plant-based water-based ink. Castor oil was introduced as a plant-based component into the polyurethane backbone. This process improves the environmental friendliness of plant-based water-based inks. By grafting dimethylolpropionic acid into the polyurethane during synthesis, hydrophilic groups are introduced. Volatile triethylamine is used as a neutralizing agent. As the amine volatilizes, a slightly acidic environment is formed, promoting the carbonyl groups on the modified carbon black and the hydrazine groups on the silicon-oxygen long chain to form carbon-nitrogen covalent crosslinks, thereby improving the abrasion resistance of plant-based water-based inks. At the same time, the tert-butylphenol grafted onto the modified carbon black can capture free radicals, prevent the oxidation of the polyurethane main chain, and improve the durability of plant-based water-based inks. Detailed Implementation

[0033] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] The raw materials used in the following examples and comparative examples are all commercially available:

[0035] The leveling agent is a type of Tigo 450, sourced from Dongguan Hongrui Chemical Co., Ltd.

[0036] The polybutylene adipate, model PBA1000, is from Xuzhou Yihuiyang New Material Co., Ltd.

[0037] The castor oil was sourced from Shandong Yunxin New Material Technology Co., Ltd.

[0038] The carbon black powder is of type BC6190 and comes from Tianjin Baochi Chemical Technology Co., Ltd.

[0039] The microcrystalline cellulose, model CP2020, is from Shanxi Jinyang Pharmaceutical Excipients Co., Ltd.

[0040] In the following examples and comparative examples, the molar amount of isophorone diisocyanate added was 0.49 times the sum of the molar amounts of hydroxyl groups contained in polybutylene adipate, castor oil, and dimethylolpropionic acid.

[0041] Example 1:

[0042] A method for preparing a plant-based water-based ink, the method comprising the following preparation steps:

[0043] (1) Microcrystalline cellulose and deionized water were mixed at a mass ratio of 1:55. The pH was adjusted to 2 by adding 0.09 mol / L hydrochloric acid solution. The mixture was stirred at 25℃ and 300 rpm in the dark for 20 min. Sodium periodate with a mass ratio of 0.9 times that of microcrystalline cellulose was added. The mixture was stirred in the dark for 9 h and then filtered. The mixture was washed three times with deionized water and freeze-dried for 11 h to obtain aldehyde-modified cellulose. Aldehyde-modified cellulose, 2-mercaptoethylamine and anhydrous ethanol were mixed at a mass ratio of 1:2:15. The mixture was stirred at 45℃ and 300 rpm for 6 h. After cooling to room temperature, the mixture was filtered. The mixture was washed three times with deionized water and dried at 55℃ for 9 h to obtain pre-modified cellulose. Pre-modified cellulose and a 34% nano-silver ethanol dispersion were ultrasonically vibrated at 55℃ for 35 min and then filtered. The mixture was washed three times with anhydrous ethanol and dried at 60℃ for 10 h to obtain modified cellulose.

[0044] (2) Octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethylsilane and tetramethylammonium hydroxide silanolate were mixed in a mass ratio of 1:1.3:0.01 and stirred at 85°C and 100 rpm for 3 h in a nitrogen atmosphere. Pentamethyldisiloxane with a mass ratio of 0.1 times that of octamethylcyclotetrasiloxane was added, and the temperature was raised to 95°C and stirred for 9 h. The temperature was raised to 130°C at a rate of 10°C / min and stirred for 50 min. The mixture was then distilled at 0.1 MPa for 2 h to obtain pre-modified silicone oil. The pre-modified silicone oil, hydrazine hydrate and ethanol were mixed in a mass ratio of 1:1:6 and stirred at 20°C and 300 rpm for 35 min. The mixture was then distilled under reduced pressure to obtain modified silicone oil.

[0045] (3) Mix polybutylene adipate and castor oil at a mass ratio of 1:0.4, add isophorone diisocyanate, stir at 85°C and 100 rpm for 4 h in a nitrogen atmosphere, add dimethylolpropionic acid at 0.07 times the mass of polybutylene adipate, cool to 75°C and continue stirring for 65 min, add dibutyl dilaurate at 0.01 times the mass of polybutylene adipate, add acetone to adjust the viscosity, cool to 60°C, add modified silicone oil at 0.01 times the mass of polybutylene adipate and chloroplatinic acid at 0.002 times the mass of polybutylene adipate, continue stirring for 5 h, rotary evaporate at 35°C for 50 min, add triethylamine at 0.056 times the mass of polybutylene adipate to neutralize for 40 min, add deionized water at 3 times the mass of polybutylene adipate, stir at 600 rpm for 40 min to obtain modified polyurethane emulsion;

[0046] (4) Aminomalonic acid, 3,5-di-tert-butyl-4-hydroxybenzaldehyde and anhydrous ethanol were mixed in a mass ratio of 1:1:8 and stirred at 45°C and 100 rpm for 6 h under a nitrogen atmosphere. The antioxidant was obtained by rotary evaporation. Carbon black powder, antioxidant, 1,5-dihydroxy-3-pentanone and toluene were mixed in a mass ratio of 1:1.1:0.3:9 and stirred at 75°C and 200 rpm for 4 h under a nitrogen atmosphere. The mixture was then filtered, washed three times with anhydrous ethanol, and dried at 60°C for 10 h to obtain modified carbon black.

[0047] (5) Grind the modified carbon black in a ball mill for 7 hours, mix it with anhydrous ethanol at a mass ratio of 1:8, and ultrasonically disperse it for 1 hour to obtain a color paste; mix the modified polyurethane emulsion, color paste, leveling agent and modified cellulose at a mass ratio of 1:0.3:0.04:0.03, and disperse it at 1500 r / min for 35 min to obtain plant-based water-based ink.

[0048] Example 2:

[0049] A method for preparing a plant-based water-based ink, the method comprising the following preparation steps:

[0050] (1) Microcrystalline cellulose and deionized water were mixed at a mass ratio of 1:60. The pH was adjusted to 3 by adding 0.11 mol / L hydrochloric acid solution. The mixture was stirred at 350 rpm in the dark for 15 min at 30 °C. Sodium periodate with a mass ratio of 1:1 that of microcrystalline cellulose was added. The mixture was stirred in the dark for 8 h and then filtered. The mixture was washed 4 times with deionized water and freeze-dried for 12 h to obtain aldehyde-modified cellulose. Aldehyde-modified cellulose, 2-mercaptoethylamine and anhydrous ethanol were mixed at a mass ratio of 1:3:20. The mixture was stirred at 350 rpm in the dark for 5 h at 50 °C. After cooling to room temperature, the mixture was filtered. The mixture was washed 4 times with deionized water and dried at 60 °C for 8 h to obtain pre-modified cellulose. Pre-modified cellulose and 40% nano-silver ethanol dispersion were ultrasonically vibrated at 60 °C for 30 min and then filtered. The mixture was washed 4 times with anhydrous ethanol and dried at 65 °C for 9 h to obtain modified cellulose.

[0051] (2) Octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethylsilane and tetramethylammonium hydroxide silanolate were mixed in a mass ratio of 1:1.4:0.02 and stirred at 90°C and 150 rpm for 2.5 h in a nitrogen atmosphere. Pentamethyldisiloxane with a mass of 0.2 times that of octamethylcyclotetrasiloxane was added, and the temperature was raised to 100°C and stirred for 8 h. The temperature was raised to 135°C at a rate of 15°C / min and stirred for 45 min. The mixture was then distilled at 0.2 MPa for 1.5 h to obtain pre-modified silicone oil. The pre-modified silicone oil, hydrazine hydrate and ethanol were mixed in a mass ratio of 1:1.5:6.5 and stirred at 25°C and 350 rpm for 30 min. The mixture was then distilled under reduced pressure to obtain modified silicone oil.

[0052] (3) Mix polybutylene adipate and castor oil at a mass ratio of 1:0.45, add isophorone diisocyanate, stir at 90°C and 200 rpm for 3 h in a nitrogen atmosphere, add dimethylolpropionic acid at 0.075 times the mass of polybutylene adipate, cool to 80°C and continue stirring for 60 min, add dibutyl dilaurate at 0.02 times the mass of polybutylene adipate, add acetone to adjust viscosity, cool to 65°C, add modified silicone oil at 0.03 times the mass of polybutylene adipate and chloroplatinic acid at 0.003 times the mass of polybutylene adipate, continue stirring for 4 h, rotary evaporate at 40°C for 40 min, add triethylamine at 0.057 times the mass of polybutylene adipate to neutralize for 35 min, add deionized water at 3.5 times the mass of polybutylene adipate, stir at 700 rpm for 35 min to obtain modified polyurethane emulsion;

[0053] (4) Aminomalonic acid, 3,5-di-tert-butyl-4-hydroxybenzaldehyde and anhydrous ethanol were mixed in a mass ratio of 1:2:8.5 and stirred at 50°C and 150 rpm for 5 h under a nitrogen atmosphere. The mixture was then rotary evaporated to obtain an antioxidant. Carbon black powder, antioxidant, 1,5-dihydroxy-3-pentanone and toluene were mixed in a mass ratio of 1:1.2:0.4:10 and stirred at 80°C and 300 rpm for 3 h under a nitrogen atmosphere. The mixture was then filtered, washed four times with anhydrous ethanol, and dried at 65°C for 9 h to obtain modified carbon black.

[0054] (5) Grind the modified carbon black in a ball mill for 8 hours, mix it with anhydrous ethanol at a mass ratio of 1:9, and ultrasonically disperse it for 2 hours to obtain a color paste; mix the modified polyurethane emulsion, color paste, leveling agent and modified cellulose at a mass ratio of 1:0.4:0.05:0.04, and disperse it at 2000 r / min for 30 min to obtain plant-based water-based ink.

[0055] Example 3:

[0056] A method for preparing a plant-based water-based ink, the method comprising the following preparation steps:

[0057] (1) Microcrystalline cellulose and deionized water were mixed at a mass ratio of 1:65. The pH was adjusted to 4 by adding 0.11 mol / L hydrochloric acid solution. The mixture was stirred at 35℃ and 400 rpm in the dark for 10 min. Sodium periodate with a mass ratio of 1.1 times that of microcrystalline cellulose was added. The mixture was stirred in the dark for 7 h and then filtered. The mixture was washed 5 times with deionized water and freeze-dried for 13 h to obtain aldehyde-modified cellulose. Aldehyde-modified cellulose, 2-mercaptoethylamine and anhydrous ethanol were mixed at a mass ratio of 1:4:25. The mixture was stirred at 55℃ and 400 rpm for 4 h. After cooling to room temperature, the mixture was filtered and washed 5 times with deionized water. The mixture was dried at 65℃ for 7 h to obtain pre-modified cellulose. Pre-modified cellulose and a 45% nano-silver ethanol dispersion were ultrasonically vibrated at 65℃ for 25 min and then filtered. The mixture was washed 5 times with anhydrous ethanol and dried at 70℃ for 8 h to obtain modified cellulose.

[0058] (2) Octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethylsilane and tetramethylammonium hydroxide silanolate were mixed in a mass ratio of 1:1.5:0.03 and stirred at 95°C and 200 rpm for 2 h in a nitrogen atmosphere. Pentamethyldisiloxane with a mass ratio of 0.3 times that of octamethylcyclotetrasiloxane was added, and the temperature was raised to 105°C and stirred for 7 h. The temperature was raised to 140°C at a rate of 20°C / min and stirred for 40 min. The mixture was then distilled at 0.3 MPa for 1 h to obtain pre-modified silicone oil. The pre-modified silicone oil, hydrazine hydrate and ethanol were mixed in a mass ratio of 1:2:7 and stirred at 30°C and 400 rpm for 25 min. The mixture was then distilled under reduced pressure to obtain modified silicone oil.

[0059] (3) Mix polybutylene adipate and castor oil at a mass ratio of 1:0.5, add isophorone diisocyanate, stir at 95°C and 300 rpm for 2 h in a nitrogen atmosphere, add dimethylolpropionic acid at 0.08 times the mass of polybutylene adipate, cool to 85°C and continue stirring for 55 min, add dibutyl dilaurate at 0.03 times the mass of polybutylene adipate, add acetone to adjust the viscosity, cool to 70°C, add modified silicone oil at 0.05 times the mass of polybutylene adipate and chloroplatinic acid at 0.004 times the mass of polybutylene adipate, continue stirring for 3 h, rotary evaporate at 45°C for 30 min, add triethylamine at 0.058 times the mass of polybutylene adipate to neutralize for 30 min, add deionized water at 4 times the mass of polybutylene adipate, stir at 800 rpm for 30 min to obtain modified polyurethane emulsion;

[0060] (4) Aminomalonic acid, 3,5-di-tert-butyl-4-hydroxybenzaldehyde and anhydrous ethanol were mixed in a mass ratio of 1:3:9 and stirred at 55°C and 200 rpm for 4 h under a nitrogen atmosphere. The mixture was then rotary evaporated to obtain an antioxidant. Carbon black powder, antioxidant, 1,5-dihydroxy-3-pentanone and toluene were mixed in a mass ratio of 1:1.3:0.5:11 and stirred at 85°C and 400 rpm for 2 h under a nitrogen atmosphere. The mixture was then filtered, washed 5 times with anhydrous ethanol, and dried at 70°C for 8 h to obtain modified carbon black.

[0061] (5) Grind the modified carbon black in a ball mill for 9 hours, mix it with anhydrous ethanol at a mass ratio of 1:10, and ultrasonically disperse it for 3 hours to obtain a color paste; mix the modified polyurethane emulsion, color paste, leveling agent and modified cellulose at a mass ratio of 1:0.5:0.06:0.05, and disperse it at 2500 r / min for 25 min to obtain plant-based water-based ink.

[0062] Comparative Example 1:

[0063] The preparation method of the plant-based water-based ink in Comparative Example 1 differs from that in Example 2 only in steps (1) and (5). Step (1) is omitted. Step (3) is modified as follows: modified carbon black is ground in a ball mill for 8 hours, mixed with anhydrous ethanol at a mass ratio of 1:9, and ultrasonically dispersed for 2 hours to obtain a color paste; modified polyurethane emulsion, color paste, leveling agent, and microcrystalline cellulose are mixed at a mass ratio of 1:0.4:0.05:0.04 and dispersed at 2000 r / min for 30 min to obtain the plant-based water-based ink. The remaining steps are the same as in Example 2.

[0064] Comparative Example 2:

[0065] The preparation method of the plant-based water-based ink in Comparative Example 2 differs from that in Example 2 only in steps (2) and (3). Step (2) is omitted. Step (3) is modified as follows: Polybutylene adipate and castor oil are mixed at a mass ratio of 1:0.45. Isophorone diisocyanate is added, and the mixture is stirred at 90°C and 200 rpm for 3 hours under a nitrogen atmosphere. Dimethylolpropionic acid is added at 0.075 times the mass of polybutylene adipate. The mixture is cooled to 80°C and stirred for 60 minutes. Dibutyl dilaurate is added at 0.02 times the mass of polybutylene adipate. Acetone is added to adjust the viscosity. The mixture is cooled to 65°C and stirred for 4 hours. The mixture is rotary evaporated at 40°C for 40 minutes. Triethylamine is added at 0.0165 times the mass of polybutylene adipate for neutralization for 35 minutes. Deionized water is added at 3.5 times the mass of polybutylene adipate. The mixture is stirred at 700 rpm for 35 minutes to obtain a modified polyurethane emulsion. The remaining steps are the same as in Example 2.

[0066] Comparative Example 3:

[0067] The preparation method of the plant-based water-based ink in Comparative Example 3 differs from that in Example 2 only in steps (4) and (5). Step (4) is omitted. Step (5) is modified as follows: carbon black powder is ground in a ball mill for 8 hours, mixed with anhydrous ethanol at a mass ratio of 1:9, and ultrasonically dispersed for 2 hours to obtain a color paste; modified polyurethane emulsion, color paste, leveling agent, and modified cellulose are mixed at a mass ratio of 1:0.4:0.05:0.04 and dispersed at 2000 r / min for 30 min to obtain the plant-based water-based ink. The remaining steps are the same as in Example 2.

[0068] Test case

[0069] 1. Antistatic properties

[0070] Test method: The plant-based water-based inks obtained from each example and comparative example were screen-printed onto PET substrates according to GB / T1410-2006, left to stand at 60°C for 30 minutes, and the surface resistance was tested using an SL-030 surface resistance tester.

[0071] 2. Abrasion resistance

[0072] Test method: The plant-based water-based inks obtained in each example and comparative example were prepared according to GB / T13217-2009, using PET film as the test substrate to prepare the ink layer to be tested. After standing at 60°C for 30 minutes, the ink was removed and cooled to room temperature. The surface of the printed sample was vigorously wiped with a cotton ball soaked in deionized water, and the peeling of the ink layer was recorded.

[0073] 3. Durability

[0074] Test Method: The plant-based water-based inks obtained in each example and comparative example were prepared according to GB / T13217-2009. Using PET film as the test substrate, the ink layers were placed in the solution at 60°C for 30 minutes, then cooled to room temperature. Adhesive tape was applied to the surface of the ink layer and pressed firmly. The tape was quickly peeled off while maintaining a right angle with the ink layer. A 2mm wide grid paper was placed under the ink layer, and the number of remaining ink layers and the number of ink layers removed by the tape were observed. The ink layer adhesion strength A1 was calculated as: (Number of ink layers / (Number of ink layers + Number of removed ink layers)) * 100%. The ink layers were also prepared using PET film as the test substrate, placed in the solution at 60°C for 30 minutes, then cooled to room temperature and aged under a xenon lamp for 24 hours. The ink layer adhesion strength A2 was calculated, and the durability was calculated as: A2 / A1 * 100%.

[0075] Table 1 below shows the analysis results of the antistatic, abrasion resistance and durability of the plant-based water-based inks of Examples 1-3 and Comparative Examples 1-3 of the present invention.

[0076] Table 1

[0077]

[0078] A comparison of the experimental data from Examples 1-3 and Comparative Examples 1-3 in Table 1 reveals that the plant-based water-based ink prepared by this invention has good antistatic, abrasion resistance, and durability.

[0079] Comparative Example 1: Unmodified microcrystalline cellulose; By comparison, Examples 1, 2, and 3 showed lower surface resistance compared to Comparative Example 1, indicating that grafting 2-mercaptoethylamine onto microcrystalline cellulose via Schiff base reaction utilizes the strong bond of S-Ag to generate chemical adsorption on the surface of nano-silver, forming an electron transport pathway and improving the antistatic properties of plant-based water-based inks.

[0080] Comparative Example 2 was without grafted modified silicone oil. By comparison, the ink layers of Examples 1, 2, and 3 showed no peeling compared to Comparative Example 2, indicating that grafting flexible organosilicon long chains onto the polyurethane backbone via hydrosilylation reduces the coefficient of friction and improves the abrasion resistance of plant-based water-based inks. Simultaneously, the formation of hydrazide groups on the siloxane long chains forms a crosslinking network with the carbonyl groups on the modified carbon black, further enhancing the abrasion resistance of plant-based water-based inks.

[0081] Comparative Example 3: Unmodified carbon black powder; By comparison, the ink layer of Comparative Example 3 showed no peeling and had a higher durability than Examples 1, 2, and 3. This indicates that by grafting dimethylolpropionic acid into hydrophilic groups during the polyurethane synthesis process and using volatile triethylamine as a neutralizing agent, a slightly acidic environment is formed as the amine volatilizes, promoting the carbonyl groups on the modified carbon black and the hydrazine groups on the silicon-oxygen long chain to form carbon-nitrogen covalent crosslinks, thereby improving the abrasion resistance of plant-based water-based inks. At the same time, the tert-butylphenol grafted onto the modified carbon black can capture free radicals, prevent the oxidation of the polyurethane main chain, and improve the durability of plant-based water-based inks.

[0082] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a plant-based water-based ink, characterized in that, The preparation steps include the following: (1) Mix microcrystalline cellulose and deionized water, add hydrochloric acid solution, stir in the dark, add sodium periodate, stir and filter, wash and dry to obtain aldehyde-modified cellulose; mix aldehyde-modified cellulose, 2-mercaptoethylamine and anhydrous ethanol, stir, cool and filter, wash and dry to obtain pre-modified cellulose. The pre-modified cellulose and nano-silver ethanol dispersion were ultrasonically vibrated, filtered, washed and dried to obtain modified cellulose. (2) Mix octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethylsilane and tetramethylammonium hydroxide silanolate, stir, add pentamethyldisiloxane, heat and stir, heat and stir, distill to obtain pre-modified silicone oil; mix pre-modified silicone oil, hydrazine hydrate and ethanol, stir, distill under reduced pressure to obtain modified silicone oil; (3) Mix polybutylene adipate and castor oil, add isophorone diisocyanate, add dimethylolpropionic acid in a nitrogen atmosphere, cool and stir, add dibutyl laurate and acetone, cool, add modified silicone oil and chloroplatinic acid, continue stirring, rotary evaporate, add triethylamine, add deionized water, stir, and obtain modified polyurethane emulsion; (4) Mix aminomalonic acid, 3,5-di-tert-butyl-4-hydroxybenzaldehyde and anhydrous ethanol, stir in a nitrogen atmosphere, and rotary evaporate to obtain an antioxidant; mix carbon black powder, antioxidant, 1,5-dihydroxy-3-pentanone and toluene, stir in a nitrogen atmosphere, filter, wash and dry to obtain modified carbon black. (5) Grind the modified carbon black with a ball mill, mix it with anhydrous ethanol, and disperse it by ultrasonication to obtain a color paste; mix the modified polyurethane emulsion, color paste, leveling agent and modified cellulose, disperse them to obtain plant-based water-based ink.

2. The method for preparing a plant-based water-based ink according to claim 1, characterized in that, The preparation process of the modified cellulose in step (1) is as follows: the pre-modified cellulose and the nano-silver ethanol dispersion with a mass fraction of 35%~45% are ultrasonically vibrated at 55~65℃ for 25~35min, filtered, washed with anhydrous ethanol 3~5 times, and dried at 60~70℃ for 8~10h to obtain the modified cellulose. The preparation process of the pre-modified cellulose is as follows: aldehyde-modified cellulose, 2-mercaptoethylamine and anhydrous ethanol are mixed at a mass ratio of 1:(2~4):(15~25), stirred at 45~55℃ and 300~400rpm for 4~6h, cooled naturally to room temperature and filtered, washed with deionized water 3~5 times, and dried at 55~65℃ for 7~9h to obtain the pre-modified cellulose; The preparation process of the aldehyde-modified cellulose is as follows: microcrystalline cellulose and deionized water are mixed at a mass ratio of 1:(55~65), and 0.09~0.11mol / L hydrochloric acid solution is added to adjust the pH to 2~4. The mixture is stirred in the dark at 25~35℃ and 300~400rpm for 10~20min. 0.9~1.1 times the mass of sodium periodate of microcrystalline cellulose is added, and the mixture is stirred in the dark for 7~9h. After filtration, the mixture is washed 3~5 times with deionized water and freeze-dried for 11~13h to obtain aldehyde-modified cellulose.

3. The method for preparing a plant-based water-based ink according to claim 1, characterized in that, The preparation process of the modified silicone oil in step (2) is as follows: pre-modified silicone oil, hydrazine hydrate and ethanol are mixed in a mass ratio of 1:(1~2):(6~7), stirred at 20~30℃ and 300~400rpm for 25~35min, and distilled under reduced pressure to obtain modified silicone oil; The preparation process of the pre-modified silicone oil is as follows: Octamethylcyclotetrasiloxane, 2-methyl ester ethyl dimethoxymethylsilane and tetramethylammonium hydroxide silanolate are mixed at a mass ratio of 1:(1.3~1.5):(0.01~0.03), stirred at 85~95℃ and 100~200rpm for 2~3h in a nitrogen atmosphere, and then pentamethyldisiloxane at 0.1~0.3 times the mass of octamethylcyclotetrasiloxane is added. The temperature is raised to 95~105℃ and stirring is continued for 7~9h. The temperature is raised to 130~140℃ at a rate of 10~20℃ / min and stirring is continued for 40~50min. The mixture is then distilled at 0.1~0.3MPa for 1~2h to obtain the pre-modified silicone oil.

4. The method for preparing a plant-based water-based ink according to claim 1, characterized in that, The preparation process of the modified polyurethane emulsion in step (3) is as follows: Polybutylene adipate and castor oil are mixed at a mass ratio of 1:(0.4~0.5), isophorone diisocyanate is added, and the mixture is stirred for 2~4 hours at 85~95℃ and 100~300rpm under a nitrogen atmosphere. Then, dimethylolpropionic acid (DMPO) at 0.07~0.08 times the mass of polybutylene adipate is added. The mixture is cooled to 75~85℃ and stirred for 55~65 minutes. Dibutyl dilaurate (DICO) at 0.01~0.03 times the mass of polybutylene adipate is added, and acetone is added to adjust the viscosity. Cool to 60-70℃, add 0.01-0.05 times the mass of polybutylene adipate modified silicone oil and 0.002-0.004 times the mass of polybutylene adipate chloroplatinic acid, continue stirring for 3-5 hours, rotary evaporate at 35-45℃ for 30-50 minutes, add 0.056-0.058 times the mass of polybutylene adipate triethylamine to neutralize for 30-40 minutes, add 3-4 times the mass of polybutylene adipate deionized water, stir at 600-800 rpm for 30-40 minutes to obtain modified polyurethane emulsion; The molar amount of isophorone diisocyanate added is 0.49 times the sum of the molar amounts of hydroxyl groups contained in polybutylene adipate, castor oil, and dimethylolpropionic acid.

5. The method for preparing a plant-based water-based ink according to claim 1, characterized in that, The preparation process of the modified carbon black in step (4) is as follows: carbon black powder, antioxidant, 1,5-dihydroxy-3-pentanone and toluene are mixed in a mass ratio of 1:(1.1~1.3):(0.3~0.5):(9~11), stirred in a nitrogen atmosphere at 75~85℃ and 200~400rpm for 2~4h, filtered, washed 3~5 times with anhydrous ethanol, and dried at 60~70℃ for 8~10h to obtain modified carbon black; The antioxidant is prepared by mixing aminomalonic acid, 3,5-di-tert-butyl-4-hydroxybenzaldehyde and anhydrous ethanol in a mass ratio of 1:(1~3):(8~9), stirring in a nitrogen atmosphere at 45~55℃ and 100~200rpm for 4~6h, and then rotary evaporating to obtain the antioxidant.

6. The method for preparing a plant-based water-based ink according to claim 1, characterized in that, The preparation process of the plant-based water-based ink in step (5) is as follows: the modified polyurethane emulsion, color paste, leveling agent and modified cellulose are mixed in a mass ratio of 1:(0.3~0.5):(0.04~0.06):(0.03~0.05) and dispersed at 1500~2500r / min for 25~35min to obtain the plant-based water-based ink; The preparation process of the color paste is as follows: the modified carbon black is ground in a ball mill for 7-9 hours, mixed with anhydrous ethanol at a mass ratio of 1:(8-10), and ultrasonically dispersed for 1-3 hours to obtain the color paste.

7. A plant-based water-based ink prepared by the method of preparing plant-based water-based ink according to any one of claims 1 to 6.

Images