A green printing varnish and a preparation method thereof

Abstract

This invention relates to a green and environmentally friendly printing varnish and its preparation method, belonging to the field of printing varnish technology. In this invention, the stability, moisture resistance, and abrasion resistance of the printing varnish are improved by adding a mixture of halloysite nanotubes, thymol, and sodium alginate. The addition of lanolin and wax emulsion enhances the printing quality and durability of the varnish, while also reducing machine wear and extending equipment lifespan. Furthermore, the addition of lanthanide rare earth elements further improves the durability and abrasion resistance of the printing varnish.

Description

Technical Field

[0001] This invention belongs to the field of printing varnish technology, and relates to a green and environmentally friendly printing varnish and its preparation method. Background Technology

[0002] The market demands increasingly higher moisture-proof performance from paper packaging for frozen products. Since frozen products are stored in freezers, the freezer doors need to be opened frequently during sales. Frost adhering to the outer packaging liquefies when exposed to warm air, making the cardboard box soft to the touch or even causing it to break, thus contaminating the food contents and endangering human health.

[0003] Lamination is the best way to improve the moisture resistance of cardboard, and the commonly used laminating material is polyethylene terephthalate (PET). However, laminating materials are non-degradable and have poor environmental performance. With increasing environmental protection requirements, moisture-resistant and environmentally friendly printing varnishes are gradually replacing lamination. This invention improves the moisture resistance, abrasion resistance, and scratch resistance of commonly used varnishes by adjusting their formulations, thus replacing the lamination process while meeting customer needs. Summary of the Invention

[0004] The purpose of this invention is to provide a green and environmentally friendly printing varnish and its preparation method, which has the characteristics of being wear-resistant, scratch-resistant, and moisture-proof.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A green and environmentally friendly printing varnish, the formulation of which is as follows (by weight percentage):

[0007] Waterborne polyurethane emulsion 20-35%, styrene 10-15%, silica 7-10%, wax emulsion 3-8%, lanolin 1-3%, halloysite nanotubes 3-5%, thymol 1-3%, sodium alginate 1-3%, rare earth elements 1-3%, dispersant 1-3%, coupling agent 1-2%, deionized water 30-40%;

[0008] The preparation method of the printing varnish is as follows:

[0009] S1: Halloysite nanotubes, thymol, and sodium alginate were mixed in proportion and stirred at a speed of 300-350 r / min under an inert gas atmosphere. The reaction temperature was 80-90℃ and the reaction time was 4h. After the reaction was completed, the mixture was slowly cooled to room temperature at 3℃ / min to obtain mixture A.

[0010] S2: Mix waterborne polyurethane emulsion, styrene, and deionized water in a certain proportion, stir at a speed of 300-350 r / min, stir for 2 hours, and then heat to 50℃ to obtain mixture B;

[0011] S3: Add mixture A to mixture B, and then add silica, wax emulsion, lanolin, rare earth elements, dispersant, and coupling agent in proportion. Stir at a speed of 400-600 r / min, the reaction temperature is 50℃, the reaction time is 1 h, cool to room temperature and then sonicate for 1 h, and let stand for 12 h to obtain the final product, namely the printing varnish.

[0012] Furthermore, the rare earth element is La.

[0013] Furthermore, the dispersant is a high molecular weight nonionic polymer, polyethylene glycol, with a molecular weight range of 2000 to 10000.

[0014] Furthermore, the coupling agent is one of vinyltriethoxysilane and vinyltri-β-methoxyethoxysilane.

[0015] Furthermore, the inert gas in S1 is one or more of nitrogen, helium, and argon.

[0016] Furthermore, the ambient temperature for the static setting described in S3 is 25°C, and the humidity is 30-35%.

[0017] This invention incorporates halloysite nanotubes, thymol, and sodium alginate into the printing varnish. Halloysite nanotubes possess a large specific surface area and adsorption capacity, effectively adsorbing and stabilizing ink pigments, thus improving the varnish's stability. Thymol exhibits strong adhesion, enhancing the adhesion between the varnish and printing materials, resulting in clearer and more stable printed patterns. Sodium alginate has good viscosity and thickening ability, effectively increasing the varnish's viscosity and flowability, making it easier for the printing machine to adsorb and transfer it. Sodium alginate also possesses good dispersibility and stability, preventing sedimentation and stratification, and maintaining the varnish's uniformity and stability. Furthermore, these three substances exhibit a synergistic effect, giving the mixture antibacterial and antioxidant properties, extending the varnish's lifespan. Therefore, the addition of these three substances effectively improves the performance and effectiveness of the printing varnish.

[0018] In this invention, the addition of silica increases the consistency and viscosity of the varnish, improves its rheological properties, reduces sedimentation and settling, and increases its gloss and spreadability. Silica can also improve the wear resistance and durability of the varnish and extend its shelf life.

[0019] Lanolin is a substance with excellent lubricating and thickening properties. Adding lanolin to printing varnish can improve the wettability of the varnish, reduce the frictional resistance between the varnish and the printing paper, reduce paper jams and machine jams during the printing process, and improve printing speed and efficiency. The addition of lanolin can also improve the water resistance of the varnish. Adding wax emulsion to printing varnish can improve the anti-sticking and anti-adhesion properties of the varnish, reduce paper jams and machine jams during the printing process, and maintain the clarity and smoothness of the printed surface. At the same time, wax emulsion can also improve the abrasion resistance and durability of the varnish, extending its service life.

[0020] This invention enhances the durability and abrasion resistance of printing varnishes by incorporating rare earth elements, making printed materials less prone to fading, peeling, or wear during prolonged use, thus extending their lifespan. Rare earth elements also improve the adhesion of the varnish, allowing it to better adhere to the printing material surface, thereby improving the quality and stability of the printed material. Furthermore, rare earth elements regulate the viscosity of the varnish, making it easier to flow and print, while also shortening the drying time and improving production efficiency. Additionally, rare earth elements enhance the color saturation and brightness of the printed material, making it more vibrant and attractive. The rare earth elements added in this invention are lanthanide rare earth elements, which are renewable resources. Effective exploration, mining, and recycling can reduce the consumption of natural resources and contribute to sustainable development.

[0021] The beneficial effects of this invention are:

[0022] In this invention, the stability, moisture resistance and abrasion resistance of printing varnish are improved by adding a mixture of halloysite nanotubes, thymol and sodium alginate.

[0023] In this invention, the addition of lanolin and wax emulsion improves the printing quality and durability of printing varnish, while also reducing machine wear and extending the service life of equipment.

[0024] This invention also incorporates lanthanide rare earth elements to further improve the durability and abrasion resistance of printing varnish. Detailed Implementation

[0025] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with embodiments, is provided below.

[0026] Formula 1: 20% waterborne polyurethane emulsion, 15% styrene, 10% silica, 5% wax emulsion, 1% lanolin, 3% halloysite nanotubes, 1% thymol, 1% sodium alginate, 1% rare earth element La, 1% dispersant PEG-2000, 2% vinyltriethoxysilane, 40% deionized water;

[0027] Formula 2: 30% waterborne polyurethane emulsion, 10% styrene, 7% silica, 8% wax emulsion, 3% lanolin, 3% halloysite nanotubes, 3% thymol, 3% sodium alginate, 1% rare earth element La, 1% PEG-2000, 1% vinyltriethoxysilane, 30% deionized water;

[0028] Formula 3: 35% waterborne polyurethane emulsion, 10% styrene, 7% silica, 3% wax emulsion, 1% lanolin, 5% halloysite nanotubes, 1% thymol, 1% sodium alginate, 3% rare earth element La, 2% PEG-2000, 2% vinyltriethoxysilane, and 30% deionized water;

[0029] Formula 4: 30% waterborne polyurethane emulsion, 10% styrene, 10% silica, 5% wax emulsion, 3% lanolin, 5% halloysite nanotubes, 1% thymol, 1% sodium alginate, 3% rare earth element La, 1% PEG-2000, 1% vinyltriethoxysilane, and 30% deionized water.

[0030] Example 1

[0031] S1: Halloysite nanotubes, thymol, and sodium alginate were mixed in proportion 1 and stirred at 300 r / min under a nitrogen atmosphere. The reaction temperature was 80℃ and the reaction time was 4 h. After the reaction was completed, the mixture was slowly cooled to room temperature at 3℃ / min to obtain mixture A.

[0032] S2: Mix waterborne polyurethane emulsion, styrene, and deionized water according to ratio 1, stir at 300 r / min, stir for 2 h, and then heat to 50℃ to obtain mixture B;

[0033] S3: Add mixture A to mixture B, and then add silica, wax emulsion, lanolin, rare earth elements, dispersant, and coupling agent according to ratio 1. Stir at 400 r / min, react at 50℃ for 1 hour, cool to room temperature, sonicate for 1 hour, and let stand for 12 hours to obtain the final product. The temperature of the standing environment is 25℃ and the humidity is 30-35%, which is the printing varnish.

[0034] Example 2

[0035] S1: Halloysite nanotubes, thymol, and sodium alginate were mixed in proportion 2. The mixture was stirred at 300 r / min under a nitrogen atmosphere. The reaction temperature was 80℃ and the reaction time was 4 h. After the reaction was completed, the mixture was slowly cooled to room temperature at 3℃ / min to obtain mixture A.

[0036] S2: Mix waterborne polyurethane emulsion, styrene, and deionized water according to ratio 2, stir at 300 r / min, stir for 2 h, and then heat to 50℃ to obtain mixture B;

[0037] S3: Add mixture A to mixture B, and then add silica, wax emulsion, lanolin, rare earth elements, dispersant, and coupling agent according to ratio 2. Stir at 400 r / min, react at 50℃ for 1 hour, cool to room temperature, sonicate for 1 hour, and let stand for 12 hours to obtain the final product. The temperature of the standing environment is 25℃ and the humidity is 30-35%, which is the printing varnish.

[0038] Example 3

[0039] S1: Halloysite nanotubes, thymol, and sodium alginate were mixed in a ratio of 3. The mixture was stirred at 350 r / min under a nitrogen atmosphere. The reaction temperature was 90℃ and the reaction time was 4 h. After the reaction was completed, the mixture was slowly cooled to room temperature at 3℃ / min to obtain mixture A.

[0040] S2: Mix waterborne polyurethane emulsion, styrene, and deionized water in a ratio of 3, stir at 350 r / min, stir for 2 h, and then heat to 50 °C to obtain mixture B;

[0041] S3: Add mixture A to mixture B, and then add silica, wax emulsion, lanolin, rare earth elements, dispersant, and coupling agent according to ratio 3. Stir at 600 r / min, react at 50℃ for 1 hour, cool to room temperature, sonicate for 1 hour, and let stand for 12 hours to obtain the final product. The temperature of the standing environment is 25℃ and the humidity is 30-35%, which is the printing varnish.

[0042] Example 4

[0043] S1: Halloysite nanotubes, thymol, and sodium alginate were mixed in a ratio of 4. The mixture was stirred at 300 r / min under a nitrogen atmosphere. The reaction temperature was 80℃ and the reaction time was 4 h. After the reaction was completed, the mixture was slowly cooled to room temperature at 3℃ / min to obtain mixture A.

[0044] S2: Mix waterborne polyurethane emulsion, styrene, and deionized water at a ratio of 4, stir at 300 r / min, stir for 2 h, and then heat to 50℃ to obtain mixture B;

[0045] S3: Add mixture A to mixture B, and then add silica, wax emulsion, lanolin, rare earth elements, dispersant, and coupling agent according to ratio 4. Stir at 400 r / min, react at 50℃ for 1 hour, cool to room temperature, sonicate for 1 hour, and let stand for 12 hours to obtain the final product. The temperature of the standing environment is 25℃ and the humidity is 30-35%, which is the printing varnish.

[0046] Comparative Example 1

[0047] Compared with ratio 2, this comparative example does not include wax emulsion and lanolin, the proportion of deionized water is changed to 41%, and the other proportions remain unchanged.

[0048] S1: Halloysite nanotubes, thymol, and sodium alginate were mixed in the aforementioned proportions and stirred at 300 r / min under a nitrogen atmosphere. The reaction temperature was 80℃ and the reaction time was 4 h. After the reaction was completed, the mixture was slowly cooled to room temperature at 3℃ / min to obtain mixture A.

[0049] S2: Mix waterborne polyurethane emulsion, styrene, and deionized water according to the above-mentioned proportions, stir at a speed of 300 r / min, stir for 2 hours, and then heat to 50°C to obtain mixture B;

[0050] S3: Add mixture A to mixture B, and then add silica, rare earth elements, dispersant, and coupling agent according to the aforementioned proportions. Stir at 400 r / min, react at 50°C for 1 hour, cool to room temperature, sonicate for 1 hour, and let stand for 12 hours to obtain the final product. The temperature of the standing environment is 25°C and the humidity is 30-35%, which is the printing varnish.

[0051] Comparative Example 2

[0052] Compared with ratio 2, this comparative example does not include rare earth elements, the proportion of deionized water is changed to 31%, and the other proportions remain unchanged.

[0053] S1: Halloysite nanotubes, thymol, and sodium alginate were mixed in the aforementioned proportions and stirred at 300 r / min under a nitrogen atmosphere. The reaction temperature was 80℃ and the reaction time was 4 h. After the reaction was completed, the mixture was slowly cooled to room temperature at 3℃ / min to obtain mixture A.

[0054] S2: Mix waterborne polyurethane emulsion, styrene, and deionized water according to the above-mentioned proportions, stir at a speed of 300 r / min, stir for 2 hours, and then heat to 50°C to obtain mixture B;

[0055] S3: Add mixture A to mixture B, and then add silica, wax emulsion, lanolin, dispersant, and coupling agent according to the aforementioned proportions. Stir at 400 r / min, react at 50°C for 1 hour, cool to room temperature, sonicate for 1 hour, and let stand for 12 hours to obtain the final product. The temperature of the standing environment is 25°C and the humidity is 30-35%, which is the printing varnish.

[0056] Comparative Example 3

[0057] Compared with ratio 2, this comparative example does not include halloysite nanotubes, thymol, sodium alginate, and the proportion of deionized water is changed to 39%, while other proportions remain unchanged.

[0058] S1: Mix waterborne polyurethane emulsion, styrene, and deionized water according to the aforementioned ratio, stir at a speed of 300 r / min, stir for 2 hours, and then heat to 50°C to obtain mixture B;

[0059] S2: Add mixture A to mixture B, and then add silica, wax emulsion, lanolin, rare earth elements, dispersant, and coupling agent according to the aforementioned proportions. Stir at 400 r / min, react at 50°C for 1 hour, cool to room temperature, sonicate for 1 hour, and let stand for 12 hours to obtain the final product. The temperature of the standing environment is 25°C and the humidity is 30-35%, which is the printing varnish.

[0060] In this comparative example, halloysite nanotubes, thymol, and sodium alginate are not added. Compared with ratio 2, the proportion of deionized water is changed to 39%, while other proportions remain unchanged.

[0061] Performance testing was performed on the examples and comparative examples, and the specific testing methods are as follows.

[0062] 1. Moisture resistance test

[0063] According to GB / T 1540-2002, the COBB value of the paper and paperboard surface coated with green and environmentally friendly printing varnish was tested using an absorbency tester.

[0064] 2. Abrasion resistance test

[0065] Cut the sample to 270*60mm and fix it on the friction table of the equipment; then fix the white paper on the 4-pound load block and place it above the sample. Set the number of friction cycles to 600, 800, 1000 and 1200 times respectively, and observe the limit number of times that scratches begin to appear after friction.

[0066] 3. Scratch resistance test

[0067] According to GB / T6739-2006 pencil hardness test, the pencil was fixed on the equipment and pressed downwards at a 45° angle onto the cured green environmentally friendly printing varnish surface under a load of 500g. The hardness decreased sequentially from 3H to 3B; the hardness of the pencil tip when a 3mm scratch appeared was recorded, and the results were used to score scratch resistance.

[0068] 4. Gloss test

[0069] Gloss meter test: The gloss meter measures at a 60° angle and is placed on the surface of environmentally friendly printing varnish for testing.

[0070]

[0071]

[0072] Through the examples and comparative examples, it was found that Example 2 has the best performance.

[0073] When using this invention:

[0074] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A green printing varnish, characterized in that, The material formula of the printing varnish is composed of, by weight percentage, Waterborne polyurethane emulsion 20-35%, styrene 10-15%, silica 7-10%, wax emulsion 3-8%, lanolin 1-3%, halloysite nanotube 3-5%, thymol 1-3%, sodium alginate 1-3%, rare earth element 1-3%, dispersant 1-3%, coupling agent 1-2%, and deionized water 30-40%; The preparation method of the printing varnish is as follows, S1: halloysite nanotube, thymol, and sodium alginate are mixed in proportion, stirred at a speed of 300-350 r / min in an inert gas atmosphere, the reaction temperature is 80-90℃, the reaction time is 4h, and the mixture A is obtained after the reaction is completed and slowly reduced to room temperature at a speed of 3℃ / min; S2: waterborne polyurethane emulsion, styrene, and deionized water are mixed in proportion, stirred at a speed of 300-350 r / min, heated to 50℃ after stirring for 2h, and mixture B is obtained; S3: mixture A is added to mixture B, and silica, wax emulsion, lanolin, rare earth element, dispersant, and coupling agent are added in proportion, stirred at a speed of 400-600 r / min, the reaction temperature is 50℃, the reaction time is 1h, and the final product, i.e. the printing varnish, is obtained after being reduced to room temperature and ultrasonic for 1h, and standing for 12h.

2. The green printing varnish according to claim 1, characterized in that, The rare earth element is La.

3. The green printing varnish according to claim 1, characterized in that, The dispersant is high molecular non-ionic polymer polyethylene glycol, and the molecular weight range is 2000-10000.

4. The green printing varnish according to claim 1, characterized in that, The coupling agent is one of vinyltriethoxysilane and vinyltri-β-methoxyethoxy-silane.

5. The green printing varnish according to claim 1, characterized in that, The inert gas in S1 is one or more of nitrogen, helium, and argon.

6. The green printing varnish according to claim 1, wherein The standing environment temperature in S3 is 25℃, and the humidity is 30-35%.

Images