Alcohol-soluble polyamide resin for printing ink, preparation method, application and intaglio printing alcohol-soluble printing ink

Abstract

The invention relates to the technical field of resin for printing ink, and discloses alcohol-soluble polyamide resin for printing ink and a preparation method and application thereof.The alcohol-soluble polyamide resin is prepared from, by weight, 78-83 parts of vegetable oil dimer acid, 3-5 parts of ethidene diamine, 6-7 parts of hexamethylenediamine, 5-8 parts of methyl pentamethylene diamine, 3-5 parts of propionic acid and 2-3 parts of acrylic acid through condensation reaction, and a defoaming agent (10-15) ml / ton. The alcohol-soluble polyamide resin for ink provided by the invention is non-toxic, free of pungent smell, non-corrosive, non-combustible, non-explosive, excellent in adhesive force, excellent in gloss, particularly strong in freezing resistance and gel resistance, excellent in alcohol solubility, stability and solvent release property, and can be used for preparing gravure plastic film surface printing ink.

Description

Technical Field

[0001] The present invention relates to the technical field of resins for inks, and specifically, to an alcohol-soluble polyamide resin for inks, a preparation method, an application, and a gravure printing alcohol-soluble ink. Background Art

[0002] Polyamide resins are usually prepared by the polycondensation reaction of dibasic acids and diamines. As a chemical raw material with excellent performance and wide applications, polyamide resins have excellent chemical resistance and can resist the erosion of acids, alkalis, vegetable oils, and mineral oils. The softening point range of polyamide resins is relatively narrow, and they quickly solidify when the temperature is slightly lower than the melting point, which is different from other thermoplastic resins that have the characteristics of gradual solidification or softening. According to their properties, polyamide resins can be divided into two categories: non-reactive or neutral polyamide resins and reactive polyamide resins. Reactive polyamide resins are mainly used as curing agents for epoxy resins and in fields such as thermosetting surface coatings, adhesives, lining materials, can sealing, and casting resins. Neutral polyamide resins are gradually synthesized by the polycondensation of dimer fatty acids and amine compounds, have good flexibility and adhesiveness, and an appropriate softening point, and are widely used in the production of inks, hot-melt adhesives, and coatings. The polyamide resins used in the ink industry have significant differences in performance requirements from those used in the chemical fiber industry. Printing inks are mainly prepared by grinding and filtering a binder such as polyamide resin, pigments, and additives.

[0003] Currently, polyamide resins for inks are divided into three categories according to the types of solvents used: benzene-soluble polyamide resins, alcohol-soluble polyamide resins, and ester-soluble polyamide resins. Among them, benzene-soluble polyamide resins need to use highly toxic toluene and xylene as solvents, and are gradually phased out by the market due to their environmental and health risks; ester-soluble polyamide resins use less toxic methyl cyclohexane to replace toluene and xylene and have been widely used in inks, but with the increasingly strict national control over the pollution of volatile organic compound emissions, their development space is somewhat limited. In contrast, alcohol-soluble polyamide resins have excellent alcohol solubility and can be completely dissolved by alcohol solvents, so they are widely used in the field of printing inks.

[0004] In China, in plastic flexible packaging printing, more than 95% of the printing uses the gravure printing method. For inks using polyamide resins, their softening points need to be appropriate to avoid problems under different climatic conditions: if the softening point is too low, the printed products may stick during printing in the rainy season; if the softening point is too high, it is easy to freeze during winter use. In addition, domestic alcohol-soluble polyamide resins have poor solubility in pure alcohol solvents and high freezing points, resulting in uncoordinated comprehensive performance and difficulty in meeting the application requirements of high-performance inks. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides an alcohol-soluble polyamide resin for ink, a preparation method thereof, and an application thereof. The present invention overcomes the deficiencies of the prior art in aspects such as alcohol solubility, low-temperature performance, and environmental friendliness, and provides a high-performance polyamide resin with excellent performance, environmental stability, and wide adaptability.

[0006] To achieve the above object, the present invention adopts the following technical solutions: An alcohol-soluble polyamide resin for ink, which is prepared by condensation reaction of raw materials comprising the following components by weight: Vegetable oil dimer acid: 75 - 85 parts; Ethylenediamine: 2 - 6 parts; Hexamethylenediamine: 4 - 10 parts; Methylpentanediamine: 3 - 10 parts; Propionic acid: 2 - 8 parts; Acrylic acid: 1 - 5 parts; The alcohol-soluble polyamide resin has a freezing point of ≤ -2 °C, an ethanol tolerance of ≥ 25 ml / 10 g, an initial dryness of ≤ 28, and a softening point of ≥ 100 °C.

[0007] In the present invention, the addition of hexamethylenediamine can improve the alcohol solubility of the resin, increase the proportion of amide bonds in the product, thereby increasing the softening point of the resin, increasing the steric hindrance between molecules, destroying the regular arrangement of molecules, and thus reducing the hydrogen bond force between molecules to achieve the effects of anti-freezing and anti-gelation. The addition of methylpentanediamine not only improves the alcohol solubility of the resin but also effectively reduces the freezing point of the resin. At the same time, propionic acid and acrylic acid are added as chain inhibitors, which excellently control the average molecular weight and viscosity of the resin and increase the softening point of the resin.

[0008] In the alcohol-soluble polyamide resin for ink, the addition amount of vegetable oil dimer acid is 78 - 83 parts, such as 78 parts, 78.5 parts, 79 parts, 79.5 parts, 80 parts, 80.5 parts, 81 parts, 81.5 parts, 82 parts, 82.5 parts, 83 parts, etc., preferably 78 - 81 parts.

[0009] In the alcohol-soluble polyamide resin for ink, the addition amount of ethylenediamine is 3 - 5 parts, such as 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, etc., preferably 3 - 4 parts.

[0010] In the alcohol-soluble polyamide resin for ink, the addition amount of hexamethylenediamine is 6 - 7 parts, such as 6 parts, 6.5 parts, 7 parts, etc.

[0011] In the alcohol-soluble polyamide resin for ink, the addition amount of methylpentanediamine is 5 - 8 parts, such as 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, etc., preferably 6 - 8 parts.

[0012] In the alcohol-soluble polyamide resin for ink, the addition amount of propionic acid is 3 to 5 parts, for example, it can be 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, etc., and preferably 3 to 4 parts.

[0013] In the alcohol-soluble polyamide resin for ink, the addition amount of acrylic acid is 2 to 3 parts, for example, it can be 2 parts, 2.5 parts, 3 parts, etc.

[0014] In the alcohol-soluble polyamide resin for ink, the addition amount of the defoaming agent is (10 - 15) ml / ton, for example, it can be 10 ml / ton, 11 ml / ton, 12 ml / ton, 13 ml / ton, 14 ml / ton, 15 ml / ton, etc.

[0015] Preferably, the vegetable oil dimer acid is one or more of cottonseed oil dimer acid, soybean oil dimer acid, and palm oil dimer acid.

[0016] Preferably, the vegetable oil dimer acid is a mixture of cottonseed oil dimer acid, soybean oil dimer acid, and palm oil dimer acid, and the ratio of cottonseed oil dimer acid, soybean oil dimer acid, and palm oil dimer acid is (4 - 6):(2 - 3):(2 - 3).

[0017] Among them, "4 - 6" of the cottonseed oil dimer acid can be, for example, 4, 4.5, 5, 5.5, 6, etc.; Among them, "2 - 3" of the soybean oil dimer acid can be, for example, 2, 2.2, 2.4, 2.6, 2.8, 3, etc.; Among them, "2 - 3" of the palm oil dimer acid can be, for example, 2, 2.2, 2.4, 2.6, 2.8, 3, etc.

[0018] Furthermore, the present invention also discloses a preparation method of the alcohol-soluble polyamide resin for ink, which includes the following steps: 1) Mixing materials: Put the vegetable oil dimer acid, propionic acid, and acrylic acid into the reaction kettle, add the defoaming agent, then introduce nitrogen, stir evenly, heat up to 120°C - 130°C, and start dropping the mixture of ethylenediamine, hexamethylenediamine, and methylpentanediamine; 2) Pelletizing: Raise the material temperature to 180 - 220°C, keep it warm for 0.5 - 1.5 h, then raise the temperature to 220 - 230°C, close the nitrogen, evacuate for 1 - 1.5 h, cool to 160 - 180°C, and pelletize and package.

[0019] Among them, in the pelletizing step, when the material temperature rises to "180 - 220°C", it can be, for example, 180°C, 190°C, 200°C, 210°C, 220°C, etc.; When keeping it warm for "0.5 - 1.5 h", it can be, for example, 0.5 h, 1 h, 1.5 h, etc.; Then heating up to “220 - 230°C” can be, for example, 220°C, 222°C, 224°C, 226°C, 228°C, 230°C, etc. Vacuumizing for “1 - 1.5 h” can be, for example, 1 h, 1.1 h, 1.2 h, 1.3 h, 1.4 h, 1.5 h, etc. Cooling down to “160 - 180°C” can be, for example, 160°C, 165°C, 170°C, 175°C, 180°C, etc.

[0020] As an alternative embodiment of the present invention, the amine mixture is a mixture of ethylenediamine, hexamethylenediamine, and methylpentamethylenediamine.

[0021] As a preferred embodiment of the present invention, in the granulation step, the material temperature during heat preservation is 200°C and the heat preservation time is 1 h.

[0022] Preferably, the addition amount of the defoaming agent is 10 - 15 ml / ton.

[0023] Preferably, in the granulation step, the material temperature during heat preservation is 200°C and the heat preservation time is 1 h.

[0024] Furthermore, the present invention also discloses the application of the alcohol-soluble polyamide resin for ink as a resin binder in ink.

[0025] Furthermore, the present invention also discloses an ink resin binder, which is prepared from raw materials including the following components by weight: 38 - 44 parts of the alcohol-soluble polyamide resin as described above, 28 - 34 parts of absolute ethanol, 24 - 28 parts of isopropanol, and 4 - 8 parts of n-butanol.

[0026] In the resin binder as described above, the addition amount of the alcohol-soluble polyamide resin is 38 - 44 parts, and can be, for example, 38 parts, 39 parts, 40 parts, 41 parts, 42 parts, 43 parts, 44 parts, etc.

[0027] In the resin binder as described above, the addition amount of absolute ethanol is 28 - 34 parts, and can be, for example, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, etc.

[0028] In the resin binder as described above, the addition amount of isopropanol is 24 - 28 parts, and can be, for example, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, etc.

[0029] In the resin binder as described above, the addition amount of n-butanol is 4 - 8 parts, and can be, for example, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, etc.

[0030] Furthermore, the present invention also discloses a gravure printing alcohol-soluble ink, which includes the alcohol-soluble polyamide resin as described above.

[0031] Due to the adoption of the above technical solution, the present invention has the following remarkable technical effects: 1. Excellent alcohol solubility: The alcohol-soluble polyamide resin can be completely dissolved in alcohol solvents, with an ethanol tolerance of ≥ 25 ml / 10 g, significantly improving the dissolution performance of the resin in the ink formulation. This ensures the uniformity and stability of the ink, avoiding printing defects caused by incomplete dissolution of the resin.

[0032] 2. Low freezing point and anti-gelling property: The freezing point of the polyamide resin of the present invention is ≤ -2 °C, and it can still maintain good fluidity and usability in low-temperature environments. This effectively solves the drawback that existing alcohol-soluble polyamide resins are prone to gelation under low-temperature conditions and affect printing, ensuring the stable application of the ink under different climatic conditions.

[0033] 3. High softening point: The softening point of the polyamide resin of the present invention is ≥ 100 °C, ensuring the thermal stability of the ink under high-temperature conditions. The high softening point avoids excessive softening of the resin during the printing process, thereby improving the quality and durability of the printed matter and reducing printing defects caused by thermal deformation.

[0034] 4. Environmental friendliness: The present invention uses alcohol solvents as the main solvent, avoiding the use of benzene and ester solvents, reducing the emission of toxic and harmful substances, and meeting the requirements of current environmental protection regulations. Compared with inks using highly toxic solvents such as toluene and xylene, the ink of the present invention is more environmentally friendly and reduces the potential harm to the environment and human health.

[0035] 5. Good adhesion and gloss: The polyamide resin is used as a binder in the ink, which can significantly improve the adhesion of the ink to the plastic film, ensuring the firmness of the printed matter. At the same time, the excellent gloss performance of the resin makes the surface of the printed matter smooth and the colors bright, enhancing the overall printing quality and aesthetics.

[0036] 6. Processing stability: Through reasonable raw material ratio and process control, the present invention ensures the stable molecular structure of the polyamide resin, reducing fluctuations during the production process. This not only improves the consistency and repeatability of the product but also reduces the scrap rate caused by unstable resin performance during the production process, improving production efficiency.

[0037] 7. Economy: Using vegetable oil dimer acid as the main raw material, the cost is relatively low and the source is wide. The formula is simple, and the preparation process is easy for industrial production, with good economic benefits. Compared with using high-cost or difficult-to-obtain raw materials, the resin of the present invention has obvious advantages in cost control.

[0038] 8. Wide applicability: The alcohol-soluble polyamide resin of the present invention is not only applicable to gravure printing inks, but also can be widely used in other types of printing inks and coatings. Its excellent performance makes it have broad application prospects in fields with high environmental protection requirements such as food packaging and pharmaceutical packaging, meeting the needs of the diversified market.

[0039] In summary, the alcohol-soluble polyamide resin for inks of the present invention and its preparation method overcome the deficiencies of the prior art in aspects such as alcohol solubility, low-temperature performance, and environmental protection, and provide a high-performance polyamide resin with excellent performance, environmental protection stability, and wide adaptability. Its significant technical advantages and broad application prospects have high commercial value and potential for popularization and application. Detailed implementation manners

[0040] The following combines the embodiments of the present invention, and clearly and completely describes the technical solutions in the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0041] In order to fully demonstrate the superior performance of the alcohol-soluble polyamide resin for inks of the present invention, in combination with the above technical effects, the present invention designs the following embodiments and comparative examples. These embodiments further optimize the alcohol solubility, low freezing point, high softening point, and environmental protection performance of the resin by adjusting the raw material ratio and preparation process parameters. Embodiments

[0042] Raw material ratio (parts by weight): Vegetable oil dimer acid: 80 parts Ethylenediamine: 3.5 parts Hexamethylenediamine: 6.5 parts Methylpentanediamine: 7 parts Propionic acid: 3.5 parts Acrylic acid: 2.5 parts Defoamer: 12 ml / ton; Among them, the vegetable oil dimer acid (hereinafter the same) is a mixture of cottonseed oil dimer acid, soybean oil dimer acid, and palm oil dimer acid, and the ratio of the cottonseed oil dimer acid, soybean oil dimer acid, and palm oil dimer acid is 6:2:2.

[0043] Preparation method: 1) Mixing: Put 80 parts of vegetable oil dimer acid, 3.5 parts of propionic acid, and 2.5 parts of acrylic acid into the reaction kettle, and add 12 ml / ton of defoamer. Introduce nitrogen, stir evenly, heat to 125 °C, and slowly dropwise add a mixture of ethylenediamine, hexamethylenediamine, and methylpentanediamine; 2) Granulation: Raise the material temperature to 200 °C, hold for 1 hour, then raise the temperature to 225 °C, turn off the nitrogen, evacuate for 1.2 hours, cool to 170 °C, and carry out granulation and packaging; During the reaction of the materials in the kettle, observe the liquid level and water supply in the kettle frequently, control the material temperature, heating rate, and dropping rate of the mixed amine to prevent the materials from overflowing the kettle, blocking the condenser, and loss of materials. Example

[0044] Raw material ratio (parts by weight): Vegetable oil dimer acid: 79 parts Ethylenediamine: 4 parts Hexamethylenediamine: 6 parts Methylpentanediamine: 6.5 parts Propionic acid: 3 parts Acrylic acid: 2 parts Defoamer: 12 ml / ton.

[0045] Preparation method: 1) Mixing: Put 79 parts of vegetable oil dimer acid, 3 parts of propionic acid, and 2 parts of acrylic acid into the reaction kettle, and add 12 ml / ton of defoamer. Pass in nitrogen, stir evenly, heat to 125 °C, and slowly drop the mixture of ethylenediamine, hexamethylenediamine, and methylpentanediamine; 2) Granulation: Raise the material temperature to 200 °C, hold for 1 hour, then raise the temperature to 225 °C, turn off the nitrogen, evacuate for 1 hour, cool to 170 °C, and carry out granulation and packaging. Example

[0046] Raw material ratio (parts by weight): Vegetable oil dimer acid: 81 parts Ethylenediamine: 3 parts Hexamethylenediamine: 6 parts Methylpentanediamine: 5.5 parts Propionic acid: 3 parts Acrylic acid: 2 parts Defoamer: 12 ml / ton.

[0047] Preparation method: 1) Mixing: Put 81 parts of vegetable oil dimer acid, 3 parts of propionic acid, and 2 parts of acrylic acid into the reaction kettle, and add 12 ml / ton of defoamer. Pass in nitrogen, stir evenly, heat to 125 °C, and slowly drop the mixture of ethylenediamine, hexamethylenediamine, and methylpentanediamine; 2) Granulation: Raise the material temperature to 200 °C, hold for 1 hour, then raise the temperature to 225 °C, turn off the nitrogen, evacuate for 1.5 hours, cool to 170 °C, and carry out granulation and packaging.

[0048] Comparative Example 1 (without adding methylpentanediamine) Raw material ratio (parts by weight): Vegetable oil dimer acid: 78.5 parts Ethylenediamine: 5 parts Hexamethylenediamine: 9.5 parts Methylpentanediamine: 0 parts Propionic acid: 5 parts Acrylic acid: 2 parts Defoamer: 12 ml / ton

[0049] Preparation method: 1) Mixing: Put 78.5 parts of vegetable oil dimer acid, 5 parts of propionic acid, and 2 parts of acrylic acid into the reaction kettle, and add 1.3 ml / ton of defoamer. Introduce nitrogen, stir evenly, heat to 125 °C, and slowly dropwise add a mixture of ethylenediamine and hexamethylenediamine; 2) Pelletizing: Raise the material temperature to 200 °C, keep it warm for 1 hour, then raise the temperature to 225 °C, turn off nitrogen, evacuate for 1 hour, cool to 170 °C, and carry out pelletizing and packaging.

[0050] Comparative example 2 (without adding hexamethylenediamine and methylpentanediamine) Raw material ratio (parts by weight): Vegetable oil dimer acid: 78.5 parts Ethylenediamine: 5 parts Hexamethylenediamine: 0 parts Methylpentanediamine: 0 parts Propionic acid: 5 parts Acrylic acid: 2 parts Defoamer: 12 ml / ton

[0051] Preparation method: 1) Mixing: Put 78.5 parts of vegetable oil dimer acid, 5 parts of propionic acid, and 2 parts of acrylic acid into the reaction kettle, and add 1.3 ml / ton of defoamer. Introduce nitrogen, stir evenly, heat to 125 °C, and slowly dropwise add a mixture of ethylenediamine; 2) Pelletizing: Raise the material temperature to 200 °C, keep it warm for 1 hour, then raise the temperature to 225 °C, turn off nitrogen, evacuate for 1 hour, cool to 170 °C, and carry out pelletizing and packaging.

[0052] Comparative example 3 (only adding ethylenediamine, without adding hexamethylenediamine and methylpentanediamine) Raw material ratio (parts by weight): Vegetable oil dimer acid: 81 parts Ethylenediamine: 12 parts Hexamethylenediamine: 0 parts Methylpentanediamine: 0 parts Propionic acid: 5 parts Acrylic acid: 2 parts Defoamer: 12 ml / ton

[0053] Preparation method: 1) Mixing: Put 81 parts of vegetable oil dimer acid, 5 parts of propionic acid, and 2 parts of acrylic acid into the reaction kettle, and add 1.3 ml / ton of defoamer. Introduce nitrogen, stir evenly, heat to 125 °C, and slowly dropwise add the mixture of ethylenediamine; 2) Granulation: Raise the material temperature to 200 °C, keep it warm for 1 hour, then raise the temperature to 225 °C, turn off the nitrogen, evacuate for 1 hour, cool to 170 °C, and carry out granulation and packaging.

[0054] Comparative Example 4 (control example, without adding propionic acid) Raw material ratio (parts by weight): Vegetable oil dimer acid: 80 parts Ethylenediamine: 4 parts Hexamethylenediamine: 6 parts Methylpentanediamine: 7 parts Propionic acid: 3.5 parts Acrylic acid: 0 parts Defoamer: 12 ml / ton.

[0055] Preparation method: 1) Mixing: Put 80 parts of vegetable oil dimer acid, 0 parts of propionic acid, and 0 parts of acrylic acid into the reaction kettle, and add 12 ml / ton of defoamer. Introduce nitrogen, stir evenly, heat to 125 °C, and slowly dropwise add the mixture of ethylenediamine, hexamethylenediamine, and methylpentanediamine; 2) Granulation: Raise the material temperature to 200 °C, keep it warm for 1 hour, then raise the temperature to 225 °C, turn off the nitrogen, evacuate for 1 hour, cool to 170 °C, and carry out granulation and packaging.

[0056] Perform performance tests on the alcohol-soluble polyamide resins provided in the examples and comparative examples. The test methods are as shown below, and the test results are shown in Table 1.

[0057] Freezing point test: Conduct the test according to the method specified in QB / T4752-2014 "Alcohol-soluble polyamide resin for ink". The smaller the freezing point value, the stronger the anti-freezing and anti-gelling properties of the polyamide resin.

[0058] 2. Ethanol tolerance test: Conduct the test according to the method specified in 5.8 of QB / T4752-2014 "Alcohol-soluble polyamide resin for ink". The larger the ethanol tolerance, the stronger the alcohol solubility of the polyamide resin.

[0059] 3. Initial drying test: Conduct the test according to the method for testing the initial drying of liquid ink in 5.2 of GB / T13217.5-2023 "Ink drying test method". The appropriate initial drying property of the polyamide resin endows the ink with reasonable solvent release property, printing suitability, gloss, and rheology.

[0060] 4. Softening point test: Softening point test: According to the method specified in GB / T12007.6-1989 "Epoxy resin softening point determination method ring and ball method". The larger the softening point value, the better the thermal stability of the polyamide resin.

[0061] Table 1 Performance test comparison table Raw materials Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Vegetable oil dimer acid *1 (kg) 80 79 81 78.5 78.5 81 80 Ethylenediamine *2 (kg) 3.5 4 3 5 5 12 4 Hexamethylenediamine *3 (kg) 6.5 6 6 9.5 0 0 6 Methylpentanediamine *4 (kg) 7 6.5 5.5 0 0 0 7 Propionic acid *5 (kg) 3.5 3 3 5 5 5 3.5 Acrylic acid *6 (kg) 2.5 2 2 2 2 2 0 Defoamer *7 (ml) 12 12 12 12 12 12 12 Performance test results Freezing point (°C) -3 -2 -2 3 2 6 -1 Ethanol tolerance (ml / 10g) 28 26 25 16 16 12 20 Initial dryness 25 24 24 22 22 40 23 Softening point (°C) 111 109 107 112 114 110 100 Source of raw materials: 1. Vegetable oil dimer acid: cottonseed oil dimer acid: Zhongde brand, soybean oil dimer acid: Zhongde brand, Fujian Zhongde Energy Co., Ltd.; palm oil dimer acid, Zhongde brand, Fujian Zhongde Energy Co., Ltd.; 2. Ethylenediamine: Yangzi brand, Yangzi Petrochemical-BASF Co., Ltd.; 3. Hexamethylenediamine: Yangzi brand, Yangzi Petrochemical-BASF Co., Ltd.; 4. Methylpentanediamine: Gaoming brand, Shanghai Gaoming Chemical Co., Ltd.; 5. Propionic acid: Yangzi brand, Yangzi Petrochemical-BASF Co., Ltd.; 6. Acrylic acid: Yangzi brand, Yangzi Petrochemical-BASF Co., Ltd.; 7. Defoaming agent: Benock brand, Shandong Jining Benock Biotechnology Co., Ltd.

[0062] By comparing the examples with the comparative examples, it can be seen that the alcohol-soluble polyamide resin for ink of the present invention exhibits significant advantages in multiple performance indicators: 1. Freezing point: The freezing points of Examples 1-3 are all lower than -2°C, which are significantly better than Comparative Examples 1-3, demonstrating the superior antifreeze performance of the resin of the present invention in a low temperature environment.

[0063] 2. Ethanol tolerance: The ethanol tolerances of Examples 1-3 are all ≥25 ml / 10 g, which are much higher than 16 ml / 10 g and 12 ml / 10 g of Comparative Examples 1-3, indicating that the resin of the present invention has better alcohol solubility.

[0064] 3. Initial drying property: The initial drying property (24-25) of Examples 1-3 is better than 22 and 40 of Comparative Examples 1-3, which shows the suitable performance of the resin of the present invention in the ink drying process.

[0065] 4. Softening point: The softening points of Examples 1-3 are all ≥107°C. Although the softening points in the comparative examples are high, the overall performance of the resin of the present invention is more balanced when combined with other performance indicators.

[0066] 5. Environmental protection: Examples 1-3 all use alcohol solvents, avoiding the use of highly toxic solvents such as benzene and esters, and complying with environmental protection requirements.

[0067] 6. Adhesion and Gloss: Examples 1 - 3 showed good adhesion and gloss in ink applications. In contrast, Comparative Examples 1 - 3 may perform poorly in actual applications due to high freezing points and poor alcohol solubility. Example

[0068] A resin vehicle is prepared from raw materials including the following components by weight: 40 parts of the alcohol-soluble polyamide resin of Example 1, 30 parts of absolute ethanol, 25 parts of isopropyl alcohol, and 5 parts of n-butanol.

[0069] Preparation Method: First, draw absolute ethanol, isopropyl alcohol, and n-butanol into an oil dissolving kettle, start stirring. After the solvents are stirred evenly, add half of the alcohol-soluble polyamide for ink. After complete dissolution, add the other half of the resin. Start high-speed stirring. After stirring for (1 - 1.5) h, take samples for analysis and determination of various indicators. The results are shown in Table 2. After passing the inspection, it is reserved for use.

[0070] Table 2 Test Results of Resin Vehicle Item Technical index Appearance Light yellow transparent viscous liquid <![CDATA[Viscosity, s / coat 4 # cup, 23 °C]]> 35 Example

[0071] The formula of gravure printing alcohol-soluble ink (by weight) is shown in Table 3: Table 3 Formula of Gravure Printing Alcohol-soluble Ink Component Parts by weight (parts) Function description Resin binder 40 Provide adhesion and film-forming property, based on the alcohol-soluble polyamide resin of the present invention Dispersed pigment 50 Provide color, common organic pigments or inorganic pigments Wax additives (such as paraffin wax) 3 Increase gloss and improve surface properties Surfactant 1 Improve pigment dispersibility and prevent pigment precipitation Antistatic agent or anti-settling agent 2 Improve ink stability and prevent pigment settlement Titrant (such as antioxidant) 1 Increase the storage stability of the ink Rheological modifier 1 Adjust the rheology of the ink to ensure printing suitability Anti-settling agent (such as silane compounds) 1 Prevent pigments and additives from precipitating in the ink The preparation method is as follows: 1. Mix Pigments: Add 50 parts of dispersed pigments into an ink stirring tank, and use a high-speed stirrer (such as a shear-type high-speed disperser) to stir evenly to ensure that the pigments are fully dispersed.

[0072] 2. Add Resin Vehicle: Slowly add 40 parts of resin vehicle, and continue high-speed stirring to ensure uniform mixing of pigments and resin.

[0073] 3. Add Auxiliaries: Add 3 parts of wax auxiliaries, 1 part of surfactant, 2 parts of antistatic agent, 1 part of titrant, 1 part of rheology modifier, and 1 part of anti-settling agent in sequence. After each addition, stir well to make each auxiliary evenly distributed.

[0074] 4. Grinding and Filtration: Grind the mixed ink through a grinder (such as a high-shear grinder) to ensure that the pigment particles are fine and reach the required particle size distribution (such as ≤10 microns). Subsequently, perform filtration treatment (such as microfiltration membrane filtration) to remove undispersed particles and impurities.

[0075] 5. Packaging and Storage: Package the prepared gravure printing alcohol-soluble ink and store it in a sealed container to avoid solvent volatilization and contamination.

[0076] 6. The performance test results are shown in Table 4: Table 4 Performance Test Results Item Value Freezing point (°C) -3 Ethanol tolerance (ml / 10g) 28 Initial dryness (seconds) 25 Softening point (°C) 111 Adhesion Excellent (meeting the standard) Glossiness High Color vividness High Environmental friendliness Meeting the green standard The foregoing is a description of embodiments of the present invention. Through the above description of the disclosed embodiments, those skilled in the art can implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. An alcohol-soluble polyamide resin for ink, characterized in that: The alcohol-soluble polyamide resin is prepared by condensation reaction of raw materials including the following components in parts by weight: Vegetable oil dimer acid: 75-85 parts; Ethylenediamine: 2-6 parts; Hexamethylenediamine: 4-10 parts; Methylpentanediamine: 3-10 parts; Propionic acid: 2-8 parts; Acrylic acid: 1-5 parts; The alcohol-soluble polyamide resin has a freezing point of ≤-2°C, an ethanol tolerance of ≥25 ml / 10g, an initial dryness of ≤28, and a softening point of ≥100°C.

2. The alcohol-soluble polyamide resin for ink according to claim 1, characterized in that: The alcohol-soluble polyamide resin is prepared by condensation reaction of raw materials including the following components in parts by weight: Vegetable oil dimer acid: 78-83 parts; Ethylenediamine: 3-5 parts; Hexamethylenediamine: 6-7 parts; Methylpentanediamine: 5-8 parts; Propionic acid: 3-5 parts; Acrylic acid: 2 to 3 parts.

3. The alcohol-soluble polyamide resin for ink according to claim 1 or 2, characterized in that: The vegetable oil dimer acid is one or more of cottonseed oil dimer acid, soybean oil dimer acid and palm oil dimer acid.

4. The alcohol-soluble polyamide resin for ink according to claim 3, characterized in that: The vegetable oil dimer acid is a mixture of cottonseed oil dimer acid, soybean oil dimer acid and palm oil dimer acid, and the ratio of cottonseed oil dimer acid, soybean oil dimer acid and palm oil dimer acid is (4-6): (2-3): (2-3).

5. The method for preparing the alcohol-soluble polyamide resin for ink according to any one of claims 1 to 4, characterized in that: The following steps are involved: 1) Mixing: Put vegetable oil dimer acid, propionic acid and acrylic acid into the reactor, add defoamer, then pass nitrogen, stir evenly, heat to 120℃~130℃, and start to drop a mixture of ethylenediamine, hexamethylenediamine and methylpentamethylenediamine; 2) Granulation: The material temperature rises to 180-220℃, keeps warm for 0.5-1.5h, then rises to 220-230℃, turns off the nitrogen, evacuates for 1-1.5h, cools to 160-180℃, and granulates and packages.

6. The method for preparing an alcohol-soluble polyamide resin for ink according to claim 5, characterized in that: The amount of the defoamer added is 10-15 ml / ton.

7. The method for preparing an alcohol-soluble polyamide resin for ink according to claim 5, characterized in that: In the granulation step, the material temperature during heat preservation is 200° C. and the heat preservation is performed for 1 hour.

8. Use of the alcohol-soluble polyamide resin for ink according to any one of claims 1 to 4 as a resin binder in ink.

9. An ink resin binder, characterized in that: The resin connecting material is prepared by using raw materials including the following components based on 100 parts by weight: 38-44 parts of the alcohol-soluble polyamide resin according to any one of claims 1 to 4, 28-34 parts of anhydrous ethanol, 24-28 parts of isopropanol, and 4-8 parts of n-butanol.

10. An alcohol-soluble ink for gravure printing, characterized in that: The ink comprises the alcohol-soluble polyamide resin according to any one of claims 1 to 4.