Hydrophobic ink and preparation process thereof

Abstract

The invention discloses hydrophobic ink and a preparation process thereof, and particularly relates to the technical field of novel ink. The hydrophobic ink is prepared from the following components in parts by mass: 20 to 35 parts of fluorocarbon resin, 15 to 30 parts of hydrophobic filler, 40 to 60 parts of organic solvent, 0.1 to 2 parts of flatting agent, 1 to 5 parts of dispersing agent, 0.5 to 1 part of defoaming agent and 1 to 3 parts of ultraviolet absorption stabilizer. By introducing the ultraviolet absorption stabilizer with a specific structure, C-H photolysis is reduced by virtue of deuterium substitution, ultraviolet photons in UVB and UVA bands can be efficiently captured and converted into harmless energy, and polymer chain breakage and pigment fading in the ink are prevented; the fluorocarbon resin and the hydrophobic filler are matched with each other to block a photooxidation chain reaction and inhibit photoagglomeration of the filler, so that the anti-UV aging service life of the ink is remarkably prolonged, and the performance of the ink can still be kept under long-time sunlight irradiation.

Description

Technical Field

[0001] The present invention relates to the technical field of novel inks, and in particular to a hydrophobic ink and a preparation process thereof. Background Art

[0002] With the continuous advancement of science and technology and people's increasing demands for a better quality of life, ink technology is also constantly developing and innovating. However, existing inks still have some problems in practical application. Traditional inks have poor hydrophobic properties and are easily affected by water, resulting in blurring and fading, which affects the aesthetics and durability of printed products. This problem is particularly prominent in printing applications that require long-term clarity and vividness, such as outdoor advertising and packaging materials.

[0003] Furthermore, existing inks lack weather resistance. Prolonged exposure to sunlight and ultraviolet rays accelerates the aging process of inks, causing their color to fade and performance to degrade. This not only shortens the lifespan of printed products but also increases replacement and maintenance costs. The ink preparation process also presents challenges. The dispersibility and stability of inks are difficult to control, leading to sedimentation and stratification, which can affect the uniformity and consistency of printing results. Furthermore, to meet environmental requirements, higher requirements are placed on the solvent composition of inks, necessitating the search for more environmentally friendly and biodegradable organic solvents to replace traditional solvents.

[0004] In response to the above problems, the present invention proposes a hydrophobic ink and a preparation process thereof, aiming to improve the hydrophobicity, weather resistance and stability of the ink, while adopting more environmentally friendly materials and processes to meet market demand. Summary of the Invention

[0005] The purpose of the present invention is to provide a hydrophobic ink with excellent hydrophobicity, good weather resistance and strong stability to address the problems of poor hydrophobicity, insufficient weather resistance and poor stability in the ink of the prior art, so as to meet the market demand in the field of ink application.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a hydrophobic ink, comprising the following components in the following weight ratios: 20-35 parts of fluorocarbon resin, 15-30 parts of hydrophobic filler, 40-60 parts of organic solvent, 0.1-2 parts of leveling agent, 1-5 parts of dispersant, 0.5-1 parts of defoaming agent, and 1-3 parts of ultraviolet absorption stabilizer;

[0007] The ultraviolet absorption stabilizer has a structure shown in Formula 1:

[0008] Formula 1;

[0009] In the formula 1, R1 is a substituent, and specifically R1 is selected from: methyl, tert-butyl, phenyl, and cyano;

[0010] In the formula 1, D is deuterium.

[0011] Furthermore, the fluorocarbon resin is polytetrafluoroethylene.

[0012] Furthermore, the hydrophobic filler is silicon dioxide with a particle size of 50-200 nm.

[0013] Furthermore, the organic solvent is at least one of ethyl acetate, propylene glycol methyl ether or methyl isobutyl ketone.

[0014] Furthermore, the leveling agent is BYK-346.

[0015] Furthermore, the dispersant is polyethylene glycol.

[0016] Furthermore, the defoaming agent is mineral oil TEGO Foamex 810.

[0017] Furthermore, the ultraviolet absorption stabilizer is any one of the compounds shown in the following structures:

[0018]

[0019] .

[0020] A method for preparing a hydrophobic ink comprises the following steps:

[0021] S1. The organic solvent, dispersant and 1 / 2 parts by mass of a fluorocarbon resin were mixed and stirred at 800-1200 rpm for 10 min to obtain material A;

[0022] S2. The hydrophobic filler was added to the material A in three batches, with an interval of 5 min between each batch, and the speed was increased to 1500-2000 rpm and stirred for 30-60 min to obtain material B;

[0023] S3. Add the remaining fluorocarbon resin, leveling agent, dispersant, defoamer, UV stabilizer to the material B and stir at 800-1200 rpm for 20 min to obtain material C;

[0024] S4. The material C is transferred to a sand mill and ground to a fineness of ≤10 μm, vacuum defoamed, and filtered to obtain a finished product.

[0025] Furthermore, the S2 is operated at 25-40°C.

[0026] Furthermore, the grinding medium in the sand mill is zirconia beads, and the grinding time is 2-3 hours.

[0027] Furthermore, the S4 filtration is performed using a 20-50 mesh filter.

[0028] The R1 substituent and D in the UV absorbing stabilizer described in the present invention enhance the photostability of the molecule. The introduction of deuterium improves the molecule's resistance to photolysis because it can reduce the photosensitivity of hydrogen atoms; while the R1 group adjusts the polarity and UV absorption range of the molecule, allowing it to more effectively capture the UVB and / or UVA bands. When the ink is exposed to sunlight, the molecule absorbs UV photons and converts them into heat energy or harmless vibrational energy, preventing UV from inducing polymer chain breakage or pigment fading in the ink. The UV absorbing stabilizer described in the present invention works synergistically with the fluorocarbon resin. The fluorocarbon resin provides low surface tension and hydrophobic groups to form a "waterproof layer." The UV absorbing stabilizer protects the resin from UV degradation and prevents a decrease in hydrophobicity. The molecular action involves physical adsorption and / or hydrogen bonding. The stabilizer adheres to the resin surface and blocks the photooxidation chain reaction. The UV absorbing stabilizer of the present invention works synergistically with the hydrophobic filler. The hydrophobic filler enhances the hydrophobic effect by increasing the surface roughness. The UV absorption mechanism of the UV absorbing stabilizer prevents the filler from agglomerating and / or losing effectiveness due to light exposure, thereby ensuring long-term hydrophobicity. At the molecular level, the stabilizer may interact with the filler surface through van der Waals forces to maintain dispersion stability.

[0029] The hydrophobic ink component of the present invention solves three major technical problems of insufficient hydrophobicity, poor weather resistance and poor stability through synergistic effects:

[0030] 1) Hydrophobicity synergy: The core component, fluorocarbon resin (which provides low-surface-energy hydrophobic groups), is combined with hydrophobic nano-silica fillers of a specific particle size (50-200nm). The resin continuous phase wraps around the filler to form a micro-nano composite structure, significantly improving surface roughness and enhancing the hydrophobic effect.

[0031] 2) Weather resistance synergy: UV absorbing stabilizers (UV absorption 280-400nm, deuterium substitution reduces CH photolysis) are adsorbed on the surface of resin and filler through van der Waals forces or hydrogen bonds, simultaneously blocking UV oxidation breakage of resin chains and inhibiting filler photoaggregation, thus extending the anti-UV aging life;

[0032] 3) Stability synergy: Dispersants (to prevent sedimentation), defoamers (to eliminate bubbles), leveling agents (to optimize film formation) and environmentally friendly solvents (such as ethyl acetate) are combined at the process end, combined with a step-by-step addition strategy and high-speed grinding to ensure that the filler is evenly dispersed without sedimentation and a long storage period;

[0033] Ultimately, through the deep coupling of component functional design and process innovation, we achieve environmentally friendly inks with high hydrophobicity, long weather resistance and strong stability to meet the stringent requirements of outdoor applications.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. Significantly improved hydrophobicity: The present invention uses the synergistic effect of fluorocarbon resin and hydrophobic nano-silica filler of a specific particle size to construct a micro-nano composite structure and enhance surface roughness, thereby significantly improving the hydrophobicity of the ink, effectively preventing the print from being blurred or fading due to water, and making it more suitable for complex environments such as outdoor environments.

[0036] 2. Significantly enhanced weather resistance: On the one hand, the UV absorption stabilizer reduces CH photolysis by means of deuterium substitution, and the R1 group can adjust the polarity and UV absorption range, which can efficiently capture UV photons in the UVB and UVA bands and convert them into harmless energy, preventing polymer chain breakage and pigment fading in the ink; on the other hand, the fluorocarbon resin and hydrophobic filler cooperate with each other to block the photooxidation chain reaction and inhibit filler photoaggregation, thereby significantly extending the anti-UV aging life of the ink, allowing it to maintain its performance under long-term sunlight exposure.

[0037] 3. Significantly improved stability: Dispersants prevent filler sedimentation, defoamers eliminate bubbles, and leveling agents help optimize film formation. Environmentally friendly organic solvents, combined with a step-by-step addition strategy and high-speed grinding process, ensure uniform dispersion of fillers without sedimentation, significantly extending the ink's shelf life and ensuring uniformity and consistency in printing results. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The UV absorption stabilizer 1 of the present invention 1 HNMR spectrum. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] Synthesis example 1

[0041] Synthesis of UV absorbing stabilizer 1:

[0042] ;

[0043] The first step: Under a nitrogen atmosphere, 20 g of raw material 1, 12.65 g of raw material 2, 14.13 g of anhydrous potassium carbonate, 1.77 g of tetrakis(triphenylphosphine)palladium and 230 g of a mixture of toluene, ethanol and aqueous solution in a volume ratio of 2:1:1 were added to the reaction system, heated to 95 ° C and refluxed for 10 hours, turned off the heating, cooled to room temperature, allowed to stand and separated, the aqueous phase was extracted twice with ethyl acetate, the organic phases were combined, the organic phases were dried over anhydrous magnesium sulfate, filtered, and dried, and silica gel column chromatography was performed using a mixture of petroleum ether and ethyl acetate as eluent, and dried to obtain 21.01 g of intermediate 1.

[0044] The second step: under a nitrogen atmosphere, 21.01g of intermediate 1, 9.35g of raw material 3, 0.4g of tri-tert-butyl phosphine, 0.05g of palladium carbon, 11.81g of anhydrous potassium carbonate and 250g of toluene were added to the reaction system, and the temperature was raised to 120°C and refluxed for 12 hours; after completion of the reaction, the temperature was slightly lowered, and the mixture was filtered using diatomaceous earth. After the filtrate was cooled to room temperature, it was washed three times with water, the organic phase was retained, and the aqueous phase was then extracted with ethyl acetate. After combining the organic phases, the organic phase was dried over anhydrous magnesium sulfate, filtered, spin-dried, and subjected to silica gel column chromatography using a mixture of petroleum ether and ethyl acetate as eluent, and spin-dried to obtain 19.59g of ultraviolet absorption stabilizer 1.

[0045] Structure identification:

[0046] MS (m / z) of intermediate 1: [M+H] + =492;

[0047] MS (m / z) of UV absorbing stabilizer 1: [M+H] + =610;

[0048] 1HNMR (Chloroform-d) of UV absorbing stabilizer 1 δ8.86-8.80 (m, 1H), 8.07-7.83 (m, 5H), 7.71-7.45 (m, 5H), 7.26-7.17 (m, 1H), 7.11 (dd, 1H), 5.25-5.18 (m, 1H), 5.03 (d, 1H), 4.34-4.24 (m, 1H), 4.17-3.97 (m, 2H), 3.93-3.77 (m, 1H), 2.53 (s, 3H).

[0049] Synthesis Example 2-Synthesis Example 4

[0050] In Synthesis Examples 2 to 4, UV absorbing stabilizers 2 to UV absorbing stabilizers 4 were synthesized in sequence, referring to the synthesis method of Synthesis Example 1, replacing raw material 2 therein, and remaining the same as Synthesis Example 1. Specific structures of raw material 2, UV absorbing stabilizers 2 to UV absorbing stabilizers 4, MS (m / z): [M+H]+ See Table 1 for data.

[0051] Table 1. Structure of raw material 2, UV absorbing stabilizer 2-UV absorbing stabilizer 4 involved in synthesis examples 2-4, MS (m / z): [M+H] + data.

[0052]

[0053] Example 1

[0054] Preparation of a hydrophobic ink:

[0055] 1. Raw materials mass ratio:

[0056] Fluorocarbon resin: 30 parts, which is polytetrafluoroethylene;

[0057] Hydrophobic filler: 25 parts, silicon dioxide, particle size 50-200 nm;

[0058] Organic solvent: 50 parts, ethyl acetate;

[0059] Leveling agent: 1 part, BYK-346 (purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd., product number PB21308);

[0060] Dispersant: 2.5 parts, polyethylene glycol;

[0061] Defoaming agent: 0.7 parts, mineral oil TEGO Foamex 810 (purchased from Guangdong Yunxing Biotechnology Co., Ltd.);

[0062] Ultraviolet absorption stabilizer: 2 parts, which is the ultraviolet absorption stabilizer 1 synthesized in Synthesis Example 1.

[0063] 2. Preparation method:

[0064] S1. An organic solvent (ethyl acetate), a dispersant (polyethylene glycol) and 1 / 2 parts by mass (15 parts) of a fluorocarbon resin were added to a stainless steel reactor and stirred at 1000 rpm for 10 minutes to obtain a homogeneous and transparent material A;

[0065] S2. Heat material A to 30°C and add a hydrophobic filler (silicon dioxide) in three batches, with a 5-minute interval between each batch. Increase the stirring speed to 1800 rpm and continue stirring for 45 minutes to obtain a highly dispersed material B.

[0066] S3. Add the remaining fluorocarbon resin (15 parts), leveling agent (BYK-346), defoamer (TEGO Foamex810) and UV stabilizer 1 to material B and stir at 1000 rpm for 20 minutes to form a uniform material C.

[0067] S4. Transfer material C to a sand mill and grind for 2.5 hours to a fineness of ≤10 μm. Then, defoam under a vacuum of -0.09 MPa for 30 minutes, and finally filter through a 30-mesh filter to obtain the finished hydrophobic ink.

[0068] Example 2-Example 4

[0069] A hydrophobic ink was prepared by referring to the preparation method of Example 1, wherein the UV absorption stabilizer was replaced with UV absorption stabilizer 2 to UV absorption stabilizer 4 synthesized in Synthesis Example 2 to Synthesis Example 4, and the rest remained the same as Example 1.

[0070] Comparative Example 1

[0071] A hydrophobic ink was prepared by referring to the preparation method of Example 1, except that the ultraviolet absorbing stabilizer was not added, and the rest of the steps were the same as those of Example 1.

[0072] Comparative Example 2

[0073] A hydrophobic ink was prepared by referring to the preparation method of Example 1, except that the ultraviolet absorption stabilizer was replaced by comparative compound 1, and the rest remained the same as Example 1.

[0074] Comparative compound 1: .

[0075] Comparative Example 3

[0076] A hydrophobic ink was prepared by referring to the preparation method of Example 1, except that the ultraviolet absorption stabilizer was replaced by comparative compound 2, and the rest remained the same as Example 1.

[0077] Comparative compound 2: .

[0078] Comparative Example 4

[0079] A hydrophobic ink was prepared by referring to the preparation method of Example 1, except that the mass fraction of the fluorocarbon resin was changed to 45 parts, and the rest remained the same as in Example 1.

[0080] Comparative Example 5

[0081] A hydrophobic ink was prepared by referring to the preparation method of Example 1, except that the mass fraction of the hydrophobic filler was changed to 40 parts, and the rest remained the same as in Example 1.

[0082] Comparative Example 6

[0083] A hydrophobic ink was prepared by referring to the preparation method of Example 1, except that the ultraviolet absorption stabilizer was replaced with ultraviolet absorber UV-326 (CAS: 3896-11-5), and the rest of the steps were the same as those of Example 1.

[0084] Performance testing:

[0085] 1. Adhesion Test: The hydrophobic ink prepared in the embodiment and comparative example was tested according to GB / T9286. The data are shown in Table 2.

[0086] 2. Water resistance test: The hydrophobic ink prepared in the embodiment and the comparative example was tested with reference to GB / T1733. The data are shown in Table 2.

[0087] 3. Acid resistance test: A hydrophobic ink prepared in the example and comparative example was taken as a sample, and a 5% concentrated sulfuric acid solution was applied to the sample surface for 48 hours. The changes in the sample were observed. The data are shown in Table 2.

[0088] 4. Alkali resistance test: A hydrophobic ink prepared in the example and comparative example was taken as a sample, and a 5% sodium hydroxide solution was applied to the sample surface for 48 hours. The changes in the sample were observed. The data are shown in Table 2.

[0089] 5. Weather resistance test: The hydrophobic inks prepared in the examples and comparative examples were exposed to a xenon lamp aging test chamber for 2400 hours to simulate natural aging conditions such as light, condensation, and humidity changes. The exposure conditions were: radiation intensity 0.35 W / m 2 The ink was exposed to a 340nm wavelength temperature cycle of 60°C (light exposure) and 40°C (condensation exposure), and a humidity cycle of 50% ± 5% (light exposure) and 95% ± 5% (condensation exposure). The light exposure phase lasted for 8 hours, and the condensation phase (simulated rain) lasted for 4 hours. After exposure, the ink's water resistance was tested according to GB / T9286. The results are shown in Table 2.

[0090] Table 2. Performance test data of a hydrophobic ink prepared in Examples and Comparative Examples.

[0091]

[0092] Compared to the comparative examples, the hydrophobic inks prepared in the examples of the present invention significantly outperformed the comparative examples in overall performance. The examples demonstrated excellent performance across all test indicators: adhesion was stronger overall, while the comparative examples showed varying degrees of decline. In terms of water resistance, the examples showed significantly higher water resistance, while the comparative examples showed a relatively shorter duration of water resistance. In acid and alkali resistance tests, the examples remained stable throughout, showing no abnormalities, while the comparative examples generally showed signs of degradation, such as discoloration or shedding. These trends fully highlight the advantages of the present invention's formulation and process in improving the overall performance of inks.

[0093] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A hydrophobic ink, characterized in that: The invention comprises the following components in the following mass ratios: 20-35 parts of fluorocarbon resin, 15-30 parts of hydrophobic filler, 40-60 parts of organic solvent, 0.1-2 parts of leveling agent, 1-5 parts of dispersant, 0.5-1 parts of defoaming agent, and 1-3 parts of ultraviolet absorption stabilizer; The ultraviolet absorption stabilizer has a structure shown in Formula 1: Formula 1; In the formula 1, R1 is a substituent, and specifically R1 is selected from: methyl, tert-butyl, phenyl, and cyano; In the formula 1, D is deuterium.

2. A hydrophobic ink according to claim 1, characterized in that, The fluorocarbon resin is polytetrafluoroethylene.

3. A hydrophobic ink according to claim 1, characterized in that, The hydrophobic filler is silicon dioxide with a particle size of 50-200 nm.

4. A hydrophobic ink according to claim 1, characterized in that, The organic solvent is at least one of ethyl acetate, propylene glycol methyl ether or methyl isobutyl ketone.

5. A hydrophobic ink according to claim 1, characterized in that, The leveling agent is BYK-346, the dispersant is polyethylene glycol, and the defoaming agent is mineral oil TEGO Foamex 810.

6. A hydrophobic ink according to claim 1, characterized in that, The ultraviolet absorption stabilizer is any one of the compounds shown in the following structures: 。 7. A method for preparing a hydrophobic ink according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. The organic solvent, dispersant and 1 / 2 parts by mass of a fluorocarbon resin were mixed and stirred at 800-1200 rpm for 10 min to obtain material A; S2. The hydrophobic filler was added to the material A in three batches, with an interval of 5 min between each batch, and the speed was increased to 1500-2000 rpm and stirred for 30-60 min to obtain material B; S3. Add the remaining fluorocarbon resin, leveling agent, dispersant, defoamer, UV stabilizer to the material B and stir at 800-1200 rpm for 20 min to obtain material C; S4. The material C is transferred to a sand mill and ground to a fineness of ≤10 μm, vacuum defoamed, and filtered to obtain a finished product.

8. The method for preparing a hydrophobic ink according to claim 7, wherein The S2 is operated at 25-40°C.

9. The method for preparing a hydrophobic ink according to claim 7, wherein The grinding medium in the sand mill is zirconium oxide beads, and the grinding time is 2-3 hours.

10. The method for preparing a hydrophobic ink according to claim 7, wherein: The S4 filtration was performed using a 20-50 mesh filter.

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