Environment-friendly UV gloss oil coating material and preparation method thereof

Abstract

The invention provides an environment-friendly UV (ultraviolet) gloss oil coating material, which is prepared from the following components in parts by weight: 35 to 45 parts of aliphatic polyurethane acrylate, 20 to 30 parts of modified polyester resin, 3 to 5 parts of photoinitiator, 20 to 30 parts of UV monomer, 5 to 10 parts of prepolymer, 0.5 to 1 part of flatting agent, 0.03 to 0.06 part of defoaming agent, 1 to 3 parts of diethylamine, 3 to 6 parts of dispersing agent and 2 to 6 parts of solvent. The degree of functionality of the aliphatic polyurethane acrylate is 3, and the dynamic viscosity of the aliphatic polyurethane acrylate at 25 DEG C is 7000-8000 mPa.s; the modified polyester resin is polyester resin modified by sodium alginate and cinnamamide ethanol. The prepared UV gloss oil coating material is short in curing time, small in shrinkage rate, high in tensile strength and bending strength, environment-friendly and pollution-free.

Description

Technical Field

[0001] The invention belongs to the technical field of coating material preparation, and specifically relates to a method for preparing an environmentally friendly UV varnish coating material. Background Art

[0002] UV varnish coating material is a surface treatment technology that uses ultraviolet (UV) irradiation to quickly cure. This coating material is usually composed of acrylate monomers, prepolymers, photoinitiators and other additives. UV varnish coating has been widely used in many industries due to its fast curing, environmental protection, excellent physical properties and diverse appearance effects.

[0003] Patent CN116410625B provides a modified UV varnish and a method for preparing a transparent antifouling coating based on the modified varnish. Fluorine-containing monomers and fluorosilanes are used as low surface energy substances to reduce surface energy and increase the hydrophobic and oleophobic angles, thereby giving the UV varnish antifouling properties. At the same time, fluorine-containing monomers and siloxanes undergo polymerization and cross-linking reactions during the UV curing process to form long polymer chains. The addition of fluorosilanes further increases the degree of cross-linking to form a cross-linked network structure, thereby improving the adhesion and hardness of the UV varnish on the substrate.

[0004] Photoinitiators are an important component in the synthesis of UV coating materials. Although the proportion in the formula is usually not high, they are indispensable. Although there are many types of initiators at present, many photoinitiators contain harmful substances, have low initiation efficiency and poor compatibility. For example, photoinitiator TPO is a photoinitiator commonly used in nail polish. However, the European light-curing coating ink industry has classified photoinitiator TPO as reproductive toxic in the CLP (classification, labeling and packaging) regulations. Photoinitiator TPO is likely to be reclassified by the EU as a reproductive toxicity Class 1B substance in CMR. Many organic solvents are often used, such as ethanol, acetone, and aromatic hydrocarbons. These volatile organic compounds are volatile, flammable, and not conducive to transportation. They are harmful to the human body and cause great pollution to the environment. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing an environmentally friendly UV varnish coating material in view of the shortcomings of the prior art in the synthesis process of UV varnish coating materials in terms of environmental protection. The method uses aliphatic polyurethane acrylate, modified polyester resin and prepolymer as main components to prepare a UV varnish coating material with good performance and environmental friendliness.

[0006] In order to achieve the above object, the present invention provides the following technical solutions: An environment-friendly UV varnish coating material, comprising the following components in parts by weight: 35-45 parts of aliphatic polyurethane acrylate, 20-30 parts of modified polyester resin, 3-5 parts of photoinitiator, 20-30 parts of UV monomer, 5-10 parts of prepolymer, 0.5-1 part of leveling agent, 0.03-0.06 part of defoaming agent, 1-3 parts of diethylamine, 3-6 parts of dispersant, and 2-6 parts of solvent.

[0007] Furthermore, the functionality of the aliphatic polyurethane acrylate is 1-3, and the kinematic viscosity at 25 °C is 5000-8000 mPa·s.

[0008] Furthermore, the modified polyester resin is a polyester resin modified with sodium alginate and cinnamamide ethanol.

[0009] Furthermore, the prepolymer is obtained by reacting fructose, castor oil, and trans-1,4-cyclohexyl diisocyanate.

[0010] Furthermore, the photoinitiator is 1-hydroxycyclohexyl phenyl ketone or ethyl 2,4,6-trimethylbenzoyl phenylphosphinate; the UV monomer is trimethylolpropane triacrylate or isobornyl methacrylate.

[0011] Furthermore, the leveling agent is Degussa Glide410 or BYK-333; the solvent is butyl acetate or propylene glycol methyl ether acetate; the dispersant is castor oil polyoxyethylene ether; the defoaming agent is BYK-024.

[0012] A preparation method of an environment-friendly UV varnish coating material, comprising the following steps: S1: Prepare the modified polyester resin; S2: Prepare the prepolymer; S3: Take 35-45 parts of aliphatic polyurethane acrylate, 20-30 parts of modified polyester resin, 3-5 parts of photoinitiator, 20-30 parts of UV monomer, 5-10 parts of prepolymer, 1-3 parts of diethylamine, and 2-6 parts of solvent, mix them, and stir and react at a temperature of 75-85 °C for 3-5 h; S4: Add 0.5-1 part of leveling agent, 0.03-0.06 part of defoaming agent, and 3-6 parts of dispersant to step S3, stir and react at a temperature of 40-50 °C for 0.5-1.5 h to obtain the environment-friendly UV varnish coating material.

[0013] Further, step S1 is specifically as follows: Mix 10 - 15 parts of sodium alginate and 15 - 25 parts of NaIO4 for 20 - 40 min; add 5 - 10 parts of ethylene glycol thereto, then add 10 - 15 parts of cinnamamide ethanol, and heat and react at a temperature of 60 - 70 °C for 30 - 50 min; cool down to 30 - 40 °C, mix 25 - 35 parts of polyester resin, 3 - 6 parts of sodium dodecyl sulfate and 80 - 100 parts of water, and perform ultrasonic treatment at 550 - 650 W for 10 - 20 min to obtain the modified polyester resin.

[0014] Further, step S2 is specifically as follows: Take 15 - 20 parts of fructose, 2 - 3 parts of resorcinol, and 40 - 60 parts of water and mix them, heat up to 55 - 65 °C and stir for 30 - 40 min; then add 0.3 - 0.5 parts of sodium hydroxide, and at a temperature of 75 - 85 °C, add 10 - 20 parts of castor oil and 5 - 10 parts of trans - 1,4 - cyclohexyl diisocyanate, and stir for 1.5 - 3.5 h to obtain a prepolymer.

[0015] Further, 5 - 10 parts of gelatinized starch are also added in step S4.

[0016] Aliphatic polyurethane acrylate is a high - performance polymer that combines the flexibility of polyurethane with the good mechanical properties and photocuring characteristics of acrylate. Such resins are usually prepared by reacting aliphatic isocyanates with polyols to form prepolymers, and then introducing hydroxyl - containing acrylate monomers to increase the photocurable acrylate double bonds. It has strong ultraviolet resistance: Since it does not contain an aromatic ring structure, aliphatic polyurethane acrylate performs well in outdoor environments and is not easily yellowed or degraded by ultraviolet irradiation; it has good long - term stability: Suitable for applications that need to be exposed to sunlight for a long time, such as automotive headlight covers, building exterior wall coatings, etc.; it has excellent optical properties: The aliphatic structure gives the material high transparency, suitable for applications with high requirements for optical properties, such as electronic display coatings, optical lens protective films, etc.; it reduces visual interference: The high transparency makes the coating hardly affect the appearance and color of the substrate itself; it combines hardness and elasticity: Aliphatic polyurethane acrylate combines the flexibility of polyurethane and the hardness of acrylate, making the coating have both certain elasticity and good abrasion resistance; UV photocuring technology: It contains acrylate double bonds and can be cured within a few seconds by UV light irradiation, greatly improving production efficiency; it has good adhesion to a variety of substrates (such as metals, plastics, wood, etc.) and has strong adaptability; it is environmentally friendly with low VOC emissions; it has good chemical corrosion resistance such as resistance to acids, alkalis, and solvents, and can effectively protect the substrate from chemical erosion; it is suitable for application scenarios that require high chemical resistance, such as chemical equipment and laboratory instruments.

[0017] Sodium alginate is a natural polysaccharide extracted from brown algae and is widely used in many fields such as food, medicine, cosmetics and industry; Sodium alginate has good biocompatibility, will not produce toxic reactions to the human body, and can be degraded by microorganisms in the natural environment, so it is very environmentally friendly; Sodium alginate can be used to prepare sustained-release or controlled-release drug carriers, and the drug release rate can be controlled by adjusting its cross-linking degree.

[0018] Cinnamamide ethanol is an organic compound, usually synthesized by the reaction of cinnamic acid and ethanolamine. Cinnamamide ethanol exhibits certain antibacterial activity, especially has a certain inhibitory effect on Gram-positive bacteria and some fungi; Cinnamamide ethanol contains functional groups such as phenolic hydroxyl groups, and these groups endow the compound with certain antioxidant ability, which helps to delay the oxidation and deterioration of oils and fats and extend the shelf life of products.

[0019] Castor oil is a natural vegetable oil extracted from the seeds of the castor plant. It has a unique chemical composition and various industrial and medical uses. The main component of castor oil is ricinoleic acid, an unsaturated fatty acid containing a hydroxyl group with 18 carbon atoms, accounting for about 90% of the total fatty acid composition. Other minor components include linoleic acid, oleic acid, etc.; The uniqueness of ricinoleic acid lies in that it has a hydroxyl group (-OH) at the 12th carbon atom; Castor oil is easy to biodegrade and is friendly to the environment.

[0020] Compared with the prior art, the advantages and beneficial effects of the present invention are: In the present invention, oxidized sodium alginate and cinnamamide ethanol are used to modify the polyester resin. Sodium alginate grafted with hydrophobic groups on the surface reacts with the polyester resin to improve the wear resistance of the polyester resin. Cinnamamide ethanol with carbon-carbon double bonds improves the integrity and firmness of the film after curing, and enhances the wear resistance and adhesion; A bio-based prepolymer is obtained by reacting fructose, castor oil and trans-1,4-cyclohexyl diisocyanate; Under the combined action of components such as aliphatic polyurethane acrylate, photoinitiator, environmentally friendly solvent, UV monomer, leveling agent, defoaming agent, diethylamine, dispersant, etc., the crosslinking density of the UV varnish coating is increased, and good flexibility can be maintained; At the same time, due to the compounding, the curing volume shrinkage is reduced, the mechanical strength is increased, and the performance enhancement effect is achieved. Detailed implementation manners

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0022] The raw materials used in the present invention are as follows: Aliphatic polyurethane acrylate (Shanghai Baoyang Baoxin Biotechnology Co., Ltd., product number BX0011); 1-hydroxycyclohexyl phenyl ketone (Jiangsu Congzhong Chemical Co., Ltd., product number 20079); ethyl 2,4,6-trimethylbenzoyl phenylphosphonate (Hubei Shiteng Chemical Technology Co., Ltd., product number 032563); trimethylolpropane triacrylate (Hebei Clavell Biotechnology Co., Ltd., product catalog 230); isobornyl methacrylate (Jinan Huifengda Chemical Co., Ltd., product catalog 1384); butyl acetate (Jinan Chuangshi Chemical Co., Ltd., product catalog 277); propylene glycol methyl ether acetate (Shandong Jinyuanyuan New Materials Co., Ltd., product catalog 1451); castor oil polyoxyethylene ether (Shandong Xinguang Chemical Co., Ltd., product catalog 50); cinnamamide ethanol (Shandong Haizhou Bioengineering Co., Ltd., product catalog 351); polyester resin (Dongguan Tianzhihong Plasticization Co., Ltd., product number 101); castor oil (Shanghai Fangye Chemical Co., Ltd., product catalog 74); trans-1,4-cyclohexyl diisocyanate (Hubei Yongkuo Technology Co., Ltd., product number YK1763); gelatinized starch (Shandong Yonglida New Material Technology Co., Ltd., product number YLD-MSHG06).

[0023] Example 1 This example provides a preparation method of an environmentally friendly UV varnish coating material, which includes the following steps: S1: Mix 10 g of sodium alginate and 15 g of NaIO4 for 20 min; add 5 g of ethylene glycol to it, then add 10 g of cinnamamide ethanol, and heat and react at a temperature of 60 °C for 30 min; cool down to 30 °C, mix 25 g of polyester resin, 3 g of sodium dodecyl sulfate and 80 g of water, and ultrasonically treat for 10 min at 550 W to obtain the modified polyester resin; S2: Take 15 g of fructose, 2 g of resorcinol, and 40 g of water and mix them, heat up to 55 °C and stir at a rate of 500 r / min for 30 min; then add 0.3 g of sodium hydroxide, at a temperature of 75 °C, add 10 g of castor oil and 5 g of trans-1,4-cyclohexyl diisocyanate, and stir at a rate of 600 r / min for 1.5 h to obtain a prepolymer; S3: Take 35 g of aliphatic polyurethane acrylate, 20 g of modified polyester resin, 3 g of photoinitiator 1-hydroxycyclohexyl phenyl ketone, 20 g of UV monomer trimethylolpropane triacrylate, 5 g of prepolymer, 1 g of diethylamine and 2 g of solvent butyl acetate and mix them, and stir and react at a temperature of 75 °C at a rate of 500 r / min for 3 h; S4: Add 0.5 g of leveling agent Degussa Glide 410, 0.03 g of defoaming agent BYK-024, 5 g of gelatinized starch, and 3 g of dispersant castor oil polyoxyethylene ether to step S3, and stir and react at a temperature of 40°C at a rate of 500 r / min for 0.5 h to obtain the environmentally friendly UV varnish coating material.

[0024] Example 2 This example provides a preparation method of an environmentally friendly UV varnish coating material, including the following steps: S1: Mix 15 g of sodium alginate and 25 g of NaIO4 for 40 min; add 10 g of ethylene glycol thereto, then add 15 g of cinnamamide ethanol, and heat and react at a temperature of 70°C for 50 min; cool down to 40°C, mix 35 g of polyester resin, 6 g of sodium dodecyl sulfate, and 100 g of water, and perform ultrasonic treatment at 650 W for 20 min to obtain the modified polyester resin; S2: Take 20 g of fructose, 3 g of resorcinol, and 60 g of water and mix them, heat up to 65°C and stir at a rate of 600 r / min for 40 min; then add 0.5 g of sodium hydroxide, and at a temperature of 85°C, add 20 g of castor oil and 10 g of trans-1,4-cyclohexyl diisocyanate, and stir at a rate of 500 r / min for 3.5 h to obtain a prepolymer; S3: Take 45 g of aliphatic polyurethane acrylate, 30 g of modified polyester resin, 5 g of photoinitiator 2,4,6-trimethylbenzoyl phenylphosphonic acid ethyl ester, 30 g of UV monomer isobornyl methacrylate, 10 g of prepolymer, 3 g of diethylamine, and 6 g of solvent propylene glycol methyl ether acetate and mix them, and stir and react at a temperature of 85°C at a rate of 550 r / min for 5 h; S4: Add 1 g of leveling agent BYK-333, 0.06 g of defoaming agent BYK-024, 10 g of gelatinized starch, and 6 g of dispersant castor oil polyoxyethylene ether to step S3, and stir and react at a temperature of 50°C at a rate of 500 r / min for 1.5 h to obtain the environmentally friendly UV varnish coating material.

[0025] Example 3 This example provides a preparation method of an environmentally friendly UV varnish coating material, including the following steps: S1: Mix 12 g of sodium alginate and 23 g of NaIO4 for 35 min; add 8 g of ethylene glycol thereto, then add 13 g of cinnamamide ethanol, and heat and react at a temperature of 65°C for 45 min; cool down to 35°C, mix 30 g of polyester resin, 5 g of sodium dodecyl sulfate, and 90 g of water, and perform ultrasonic treatment at 600 W for 15 min to obtain the modified polyester resin; S2: Mix 18 g of fructose, 2.5 g of resorcinol, and 50 g of water, heat up to 60 °C, and stir at a rate of 500 r / min for 36 min; then add 0.4 g of sodium hydroxide, and at a temperature of 82 °C, add 15 g of castor oil and 7 g of trans-1,4-cyclohexyl diisocyanate, and stir at a rate of 500 r / min for 3 h to obtain a prepolymer; S3: Mix 40 g of aliphatic polyurethane acrylate, 25 g of modified polyester resin, 4 g of photoinitiator ethyl 2,4,6-trimethylbenzoyl phenylphosphinate, 25 g of UV monomer trimethylolpropane triacrylate, 7 g of prepolymer, 2 g of diethylamine, and 5 g of solvent propylene glycol methyl ether acetate, and stir and react at a temperature of 80 °C at a rate of 500 r / min for 4.5 h; S4: Add 0.7 g of leveling agent BYK-333, 0.04 g of defoaming agent BYK-024, 8 g of gelatinized starch, and 5 g of dispersant castor oil polyoxyethylene ether to step S3, and stir and react at a temperature of 45 °C at a rate of 600 r / min for 1 h to obtain the environmentally friendly UV varnish coating material.

[0026] Comparative Example 1 The difference between this comparative example and Example 1 is that the polyester resin was not modified in step S1, and the other steps were the same.

[0027] Comparative Example 2 The difference between this comparative example and Example 1 is that step S2 was missing, the prepolymer was not prepared, and the other steps were the same.

[0028] Comparative Example 3 The difference between this comparative example and Example 1 is that the modified polyester resin was not added in step S3, and the other steps were the same.

[0029] Comparative Example 4 The difference between this comparative example and Example 1 is that the gelatinized starch was not added in step S4, and the other steps were the same.

[0030] Comparative Example 5 The difference between this comparative example and Example 1 is that the castor oil polyoxyethylene ether was not added in step S4, and the other steps were the same.

[0031] Performance Test: For the UV varnish coating materials prepared in each example and comparative example, curing time: coat a 250-μm-thick composition on a pretreated glass sheet using a four-edge wet film coater, send it into a laser beam with a wavelength of 405 nm for curing, time it with a stopwatch, record the curing time, and touch the composition irradiated by the laser beam with a finger with a certain pressure. When it is not sticky to the touch, it is considered cured; shrinkage rate: measure the shrinkage rate by the density method. First, measure the density before and after curing using the pycnometer method according to the standard GB / T 15223-2008, and calculate the shrinkage rate; strength: prepare a test sample under the curing condition of irradiating and curing with a 405-nm-wavelength laser beam for 3 minutes, and test the tensile strength and flexural strength according to GB / T 9341. Measure the pencil hardness with a pencil hardness tester. The results are shown in the following table:

[0032] It can be seen from the above performance test results that the UV varnish coating materials prepared in Examples 1-3 have good curing time, shrinkage resistance, tensile strength and flexural strength; especially the comprehensive performance of Example 3 is the most prominent. However, in Comparative Examples 1-5, because the necessary technical solutions were not adopted, their performance in the corresponding performance tests is significantly worse than that of the examples. The above experimental results further prove the importance of the technical solutions defined in the present invention for its technical effects.

[0033] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle described in the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. An environmentally friendly UV varnish coating material, characterized in that: The invention comprises the following components in parts by weight: 35-45 parts of aliphatic polyurethane acrylate, 20-30 parts of modified polyester resin, 3-5 parts of photoinitiator, 20-30 parts of UV monomer, 5-10 parts of prepolymer, 0.5-1 parts of leveling agent, 0.03-0.06 parts of defoamer, 1-3 parts of diethylamine, 3-6 parts of dispersant and 2-6 parts of solvent.

2. The environmentally friendly UV varnish coating material according to claim 1, characterized in that: The functionality of the aliphatic polyurethane acrylate is 3, and the dynamic viscosity at 25° C. is 7000-8000 mPa·s.

3. The environmentally friendly UV varnish coating material according to claim 1, characterized in that: The modified polyester resin is a polyester resin modified by sodium alginate and cinnamamide ethanol.

4. The environmentally friendly UV varnish coating material according to claim 1, characterized in that: The prepolymer is obtained by reacting fructose, castor oil and trans-1,4-cyclohexyl diisocyanate.

5. The environmentally friendly UV varnish coating material according to claim 1, characterized in that: The photoinitiator is 1-hydroxycyclohexyl phenyl ketone or ethyl 2,4,6-trimethylbenzoyl phenylphosphonate; and the UV monomer is trimethylolpropane triacrylate or isobornyl methacrylate.

6. The environmentally friendly UV varnish coating material according to claim 1, characterized in that: The leveling agent is Digao Glide410 or BYK-333; the solvent is butyl acetate or propylene glycol methyl ether acetate; the dispersant is castor oil polyoxyethylene ether; and the defoamer is BYK-024.

7. A method for preparing an environmentally friendly UV varnish coating material, characterized in that: The steps include: S1: preparing modified polyester resin; S2: preparing prepolymer; S3: 35-45 parts of aliphatic polyurethane acrylate, 20-30 parts of modified polyester resin, 3-5 parts of photoinitiator, 20-30 parts of UV monomer, 5-10 parts of prepolymer, 1-3 parts of diethylamine and 2-6 parts of solvent are mixed, and stirred at a temperature of 75-85°C for 3-5 hours; S4: adding 0.5-1 parts of leveling agent, 0.03-0.06 parts of defoaming agent and 3-6 parts of dispersant to step S3, stirring and reacting at a temperature of 40-50° C. for 0.5-1.5 hours to obtain the environmentally friendly UV varnish coating material.

8. The method for preparing an environmentally friendly UV varnish coating material according to claim 7, characterized in that: Step S1 is specifically as follows: 10-15 parts of sodium alginate and 15-25 parts of NaIO4 are mixed for 20-40 minutes; 5-10 parts of ethylene glycol are added thereto, and then 10-15 parts of cinnamamide ethanol are added thereto, and the mixture is heated at a temperature of 60-70°C for reaction for 30-50 minutes; the temperature is lowered to 30-40°C, 25-35 parts of polyester resin, 3-6 parts of sodium dodecyl sulfate and 80-100 parts of water are mixed, and ultrasonic treatment is performed at 550-650W for 10-20 minutes to obtain the modified polyester resin.

9. The method for preparing an environmentally friendly UV varnish coating material according to claim 7, characterized in that: Step S2 is specifically as follows: 15-20 parts of fructose, 2-3 parts of resorcinol, and 40-60 parts of water are mixed, heated to 55-65° C. and stirred for 30-40 minutes; then 0.3-0.5 parts of sodium hydroxide are added, and at a temperature of 75-85° C., 10-20 parts of castor oil and 5-10 parts of trans-1,4-cyclohexyl diisocyanate are added, and stirred for 1.5-3.5 hours to obtain a prepolymer.

10. The method for preparing an environmentally friendly UV varnish coating material according to claim 7, characterized in that: In step S4, 5-10 parts of gelatinized starch are also added.

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