Water-based UV antistatic coating and preparation method of functional film of water-based UV antistatic coating

Abstract

The invention relates to the field of water-based UV (ultraviolet) antistatic coatings, in particular to a water-based UV antistatic coating which comprises 40-60 parts of water-based acrylic resin; 5 to 10 parts of tung oil; 5 to 10 parts of rosin resin; a preparation method of the functional film; the method comprises the following steps: 1, preparing a coating, 2, adjusting the state of the coating, and 3, curing to form a film. According to the water-based UV coating, the water-based acrylic resin, the tung oil and the rosin resin are adopted as main constituent materials of the coating, and other additives also adopt low-toxicity and low-irritation environment-friendly materials, so that the prepared water-based UV coating can reduce the VOC emission of the coating and improve the green and environment-friendly properties of the coating, and by adding the antistatic agent and the antistatic monomer into the coating, the anti-static property of the coating is improved. The surface resistance of the coating can be effectively reduced, the antistatic effect of the coating can be kept for a long time, and the coating is ensured to reach an ideal curing state in a short time by adopting a light-heat dual-curing mode when the coating is cured to form a film.

Description

Technical Field

[0001] The invention relates to the field of water-based UV antistatic coatings, and in particular to a method for preparing a water-based UV antistatic coating and a functional film thereof. Background Art

[0002] Waterborne UV coating is a type of waterborne polyurethane ultraviolet light-curing coating. Its principle is mainly to use UV radiation to make the photoinitiator in the coating absorb radiation energy and then split into free radicals, triggering the polymerization and cross-linking grafting reaction of the prepolymer, and solidifying into a three-dimensional network polymer in a very short time to form a coating. The coatings prepared by waterborne coatings are widely used in electronic products, communication equipment, medical devices, automotive parts and other fields.

[0003] However, the common water-based UV coatings on the market currently contain volatile organic compounds (VOCs). These VOCs will evaporate in large quantities during the production, construction and use of the coatings, which not only seriously pollute the atmospheric environment, but also pose a potential threat to people's health. In addition, the curing speed of water-based UV coatings is also a major shortcoming. Compared with traditional solvent-based coatings, the curing speed of water-based UV coatings is not ideal, and it often takes a longer time to achieve the ideal curing effect. The coating is easily disturbed by external factors during the curing process, thereby affecting its final performance and reducing the service life of the coating. Moreover, during the construction and use of the coating, due to friction and other reasons, static electricity is easily accumulated on the surface of the coating. When static electricity accumulates to a certain extent, discharge may occur, which will not only damage the coating itself, but may also interfere with nearby electronic equipment and even cause safety accidents, posing a huge hidden danger to personal safety.

[0004] Therefore, in view of the problems that the above-mentioned existing coatings contain harmful volatile substances, the film-forming and curing speed of water-based UV coatings is not ideal, and static electricity is easily accumulated on the surface after film formation, a method for preparing water-based UV antistatic coatings and their functional films can be designed. Summary of the invention

[0005] In order to overcome the problem that existing coatings contain harmful volatile substances, the film-forming and curing speed of water-based UV coatings is not ideal, and static electricity is easily accumulated on the surface after film formation.

[0006] The technical solution of the present invention is: a water-based UV antistatic coating comprises the following materials, which are formulated in the following proportions by weight: Water-based acrylic resin: 40 to 60 parts; Tung oil: 5 to 10 parts; Rosin resin: 5 to 10 parts; pH adjuster: 0.1 to 0.7 parts; Thickener: 1 to 1.5 parts; Defoaming agent: 0.2 to 0.5 parts; Wetting agent: 0.3 to 0.9 parts; Leveling agent: 0.2 to 0.8 parts; Antistatic agent: 2 to 5 parts; Antistatic monomer: 2 to 5 parts; Photoinitiator: 1 to 2 parts; Thermal curing agent: 1 to 2 parts.

[0007] Preferably, the pH adjuster is selected from ammonia water and acetic acid; the thickener is selected from hydroxyethyl cellulose, polyacrylate and polyurethane thickener.

[0008] Preferably, the antistatic agent is one of nano silicon dioxide and nano aluminum oxide.

[0009] Preferably, the antistatic monomer is one or a combination of unsaturated quaternary ammonium salt monomer, ethyl lactate, and glyceryl acrylate.

[0010] The preparation method of the water-based UV antistatic coating and the functional film thereof comprises the water-based UV antistatic coating described above, and the steps are as follows: Step 1: Preparation of coating: add water-based acrylic resin, tung oil, rosin resin, defoamer, wetting agent and leveling agent into a mixing bucket according to the formula and weight, and stir evenly with a high-speed disperser. Set the speed of the high-speed disperser to 1500 rpm to 2000 rpm and the stirring time to 30 minutes to 45 minutes to ensure that all components are fully dispersed; Then, the stirring speed is reduced, the speed of the disperser is set to 500 rpm to 800 rpm, the antistatic monomer is slowly added, the internal temperature of the stirring barrel is increased to 60°C to 80°C, and stirring is continued for 30 minutes to allow the monomer to be evenly dispersed and partially reacted in the mixture of step 1; Use a grinder to grind the paint finely until the particle size distribution reaches D90≤15μm, D50≤5μm; Step 2: Adjust the coating state. Slowly add the pH adjuster under low-speed stirring to adjust the pH value of the coating to 7.0 to 8.5; In the final mixing stage of the paint, add antistatic agent, photoinitiator and thermal curing agent to ensure uniform dispersion, add thickener to adjust the viscosity of the paint to 20 seconds to 40 seconds, and use a viscometer to measure the viscosity of the paint to ensure that it meets the construction requirements.

[0011] Filter the paint to remove impurities and particles; Step 3: Curing to form a film, evenly apply the water-based UV antistatic coating on the substrate to be treated, the coating thickness is between 20μm and 50μm, first perform UV curing, and use ultraviolet lamp to irradiate; After UV curing, heat curing is carried out, and the temperature and time are adjusted according to the type of thermal curing agent to improve the hardness and wear resistance of the coating.

[0012] Preferably, in step 2, the coating is subjected to double filtration treatment, using a 200-mesh high-precision filter and a 100-mesh high-precision filter in turn to filter the coating.

[0013] Preferably, the ultraviolet lamp setting parameters in step three are: wavelength 320-390nm, power 50W / cm²~100W / cm², irradiation time 120 seconds~360 seconds; thermal curing treatment temperature is set at 80°C~120°C, and the treatment time is 15 minutes~30 minutes.

[0014] Beneficial effects of the present invention: The present invention adopts water-based acrylic resin, tung oil and rosin resin as main components of the coating, and other additives also adopt low-toxic, low-irritation environmentally friendly materials. The water-based UV coating produced in this way can reduce the VOC emission of the coating, improve the green environmental protection of the coating, and greatly improve the safety of using the water-based UV coating. By adding antistatic agent and antistatic monomer to the coating, the surface resistance of the coating can be effectively reduced, the antistatic effect of the coating can be maintained for a long time, and static electricity can be avoided to accumulate easily, and the electronic equipment failure and personal safety hazards caused by static electricity discharge are fundamentally eliminated. By adopting a light-heat dual curing mode when the coating is cured and film-formed, the photoinitiator in the coating is quickly activated under ultraviolet irradiation, a polymerization reaction is initiated, and a coating structure is initially formed; at the same time, by auxiliary heating means, the process of the polymerization reaction is further accelerated and deepened, ensuring that the coating reaches an ideal curing state in a short time, and the coating is more durable after film formation. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the embodiments. Example

[0016] The present invention provides an embodiment: a water-based UV antistatic coating comprises the following materials, which are formulated in the following proportions by weight: Water-based acrylic resin: 50 parts; Tung oil: 7 parts; Rosin resin: 7 parts; pH regulator: 0.3 parts; Thickener: 1.3 parts; Defoaming agent: 0.3 parts; Wetting agent: 0.6 parts; Leveling agent: 0.5 parts; Antistatic agent: 3 parts; Antistatic monomer: 3.5 parts; Photoinitiator: 1 part; Heat curing agent: 1 part.

[0017] The preparation method of the water-based UV antistatic coating and the functional film thereof comprises the water-based UV antistatic coating described above, and the steps are as follows: Step 1: Preparation of coating: add water-based acrylic resin, tung oil, rosin resin, defoamer, wetting agent and leveling agent into a mixing bucket according to the formula and weight, and stir evenly with a high-speed disperser. Set the speed of the high-speed disperser to 1500 rpm to 2000 rpm and the stirring time to 30 minutes to 45 minutes to ensure that all components are fully dispersed; Then, the stirring speed is reduced, the speed of the disperser is set to 500 rpm to 800 rpm, and the antistatic monomer-ethyl lactate is slowly added, and the internal temperature of the stirring barrel is increased to 60°C to 80°C, and stirring is continued for 30 minutes to make the monomer evenly dispersed and partially reacted in the mixture of step 1; Use a grinder to grind the paint finely until the particle size distribution reaches D90≤15μm, D50≤5μm; Step 2: Adjust the coating state. Slowly add the pH adjuster - acetic acid under low-speed stirring to adjust the pH value of the coating to 7.0 to 8.5; In the final mixing stage of the paint, add antistatic agent - nano alumina, photoinitiator and thermosetting agent to ensure uniform dispersion, add thickener - polyacrylate to adjust the viscosity of the paint to 20 seconds to 40 seconds, and use a viscometer to measure the viscosity of the paint to ensure that it meets the construction requirements.

[0018] Filter the paint to remove impurities and particles; Step 3: Curing to form a film, evenly apply the water-based UV antistatic coating on the substrate to be treated, the coating thickness is between 20μm and 50μm, first perform UV curing, and use ultraviolet lamp to irradiate; After UV curing, heat curing is carried out, and the temperature and time are adjusted according to the type of thermal curing agent to improve the hardness and wear resistance of the coating.

[0019] The water-based UV antistatic coating was prepared by Example 1. The proper proportion of water-based acrylic resin, tung oil and rosin resin achieved good film-forming property and adhesion. The dual effects of photoinitiator and thermal curing agent ensured rapid curing of the coating. Example

[0020] The present invention provides an embodiment: a water-based UV antistatic coating comprises the following materials, which are formulated in the following proportions by weight: Water-based acrylic resin: 40 parts; Tung oil: 7 parts; Rosin resin: 10 parts; pH regulator: 0.1 part; Thickener: 1 part; Defoaming agent: 0.2 parts; Wetting agent: 0.4 parts; Leveling agent: 0.2 parts; Antistatic agent: 2 parts; Antistatic monomer: 5 parts; Photoinitiator: 1 part; Thermal curing agent: 1.5 parts.

[0021] The preparation method of the water-based UV antistatic coating and the functional film thereof comprises the water-based UV antistatic coating described above, and the steps are as follows: Step 1: Preparation of coating: add water-based acrylic resin, tung oil, rosin resin, defoamer, wetting agent and leveling agent into a mixing bucket according to the formula and weight, and stir evenly with a high-speed disperser. Set the speed of the high-speed disperser to 1500 rpm to 2000 rpm and the stirring time to 30 minutes to 45 minutes to ensure that all components are fully dispersed; Then, the stirring speed is reduced, the speed of the disperser is set to 500 rpm to 800 rpm, and the antistatic monomer-unsaturated quaternary ammonium salt monomer is slowly added, the internal temperature of the stirring barrel is increased to 60° C. to 80° C., and stirring is maintained for 30 minutes to allow the monomer to be evenly dispersed and partially reacted in the mixture of step 1; Use a grinder to grind the paint finely until the particle size distribution reaches D90≤15μm, D50≤5μm; Step 2: Adjust the coating state. Slowly add pH adjuster - ammonia water under low-speed stirring to adjust the pH value of the coating to 7.0 to 8.5; In the final mixing stage of the paint, add antistatic agent - nano-silica, photoinitiator and thermal curing agent to ensure uniform dispersion, add thickener - hydroxyethyl cellulose to adjust the viscosity of the paint to 20 seconds to 40 seconds, and use a viscometer to measure the viscosity of the paint to ensure that it meets the construction requirements.

[0022] Filter the paint to remove impurities and particles; Step 3: Curing to form a film, evenly apply the water-based UV antistatic coating on the substrate to be treated, the coating thickness is between 20μm and 50μm, first perform UV curing, and use ultraviolet lamp to irradiate; After UV curing, heat curing is carried out, and the temperature and time are adjusted according to the type of thermal curing agent to improve the hardness and wear resistance of the coating.

[0023] By preparing a water-based UV antistatic coating according to Example 2, the proportion of rosin resin is increased, the hardness and wear resistance of the coating are improved, and the combination of antistatic agent and antistatic monomer can maintain excellent antistatic performance after curing into a film.

Claims

1. Water-based UV antistatic coating, characterized in that: The following materials are included, and the proportions are as follows by weight: Water-based acrylic resin: 40 to 60 parts; Tung oil: 5 to 10 parts; Rosin resin: 5 to 10 parts; pH adjuster: 0.1 to 0.7 parts; Thickener: 1 to 1.5 parts; Defoaming agent: 0.2 to 0.5 parts; Wetting agent: 0.3 to 0.9 parts; Leveling agent: 0.2 to 0.8 parts; Antistatic agent: 2 to 5 parts; Antistatic monomer: 2 to 5 parts; Photoinitiator: 1 to 2 parts; Thermal curing agent: 1 to 2 parts.

2. The water-based UV antistatic coating according to claim 1, characterized in that: The pH value adjuster is selected from ammonia water and acetic acid; the thickener is selected from hydroxyethyl cellulose, polyacrylate and polyurethane thickener.

3. The water-based UV antistatic coating according to claim 1, characterized in that: The antistatic agent is one of nano silicon dioxide and nano aluminum oxide.

4. The water-based UV antistatic coating according to claim 1, characterized in that: The antistatic monomer is one or a combination of unsaturated quaternary ammonium salt monomer, ethyl lactate and glyceryl acrylate.

5. A method for preparing a water-based UV antistatic coating and a functional film thereof, characterized in that The method comprises the water-based UV antistatic coating according to claim 1, wherein the steps are as follows: Step 1: Preparation of coating: add water-based acrylic resin, tung oil, rosin resin, defoamer, wetting agent and leveling agent into a mixing bucket according to the formula and weight, and stir evenly with a high-speed disperser. Set the speed of the high-speed disperser to 1500 rpm to 2000 rpm and the stirring time to 30 minutes to 45 minutes to ensure that all components are fully dispersed; Then, the stirring speed is reduced, the speed of the disperser is set to 500 rpm to 800 rpm, the antistatic monomer is slowly added, the internal temperature of the stirring barrel is increased to 60°C to 80°C, and stirring is continued for 30 minutes to allow the monomer to be evenly dispersed and partially reacted in the mixture of step 1; Use a grinder to grind the paint finely until the particle size distribution reaches D90≤15μm, D50≤5μm; Step 2: Adjust the coating state. Slowly add the pH adjuster under low-speed stirring to adjust the pH value of the coating to 7.0 to 8.5; In the final mixing stage of the paint, add antistatic agent, photoinitiator and thermal curing agent to ensure uniform dispersion, add thickener to adjust the viscosity of the paint to 20 seconds to 40 seconds, and use a viscometer to measure the viscosity of the paint to ensure that it meets the construction requirements.

6. Filter the paint to remove impurities and particles; Step 3: Curing to form a film, evenly apply the water-based UV antistatic coating on the substrate to be treated, the coating thickness is between 20μm and 50μm, first perform UV curing, and use ultraviolet lamp to irradiate; After UV curing, heat curing is carried out, and the temperature and time are adjusted according to the type of thermal curing agent to improve the hardness and wear resistance of the coating.

7. The method for preparing the water-based UV antistatic coating and the functional film thereof according to claim 5, characterized in that: In step 2, the paint is subjected to double filtration treatment, using a 200-mesh high-precision filter and a 100-mesh high-precision filter to filter the paint in turn.

8. The method for preparing the water-based UV antistatic coating and the functional film thereof according to claim 5, characterized in that: In step 3, the UV lamp setting parameters are: wavelength 320-390nm, power 50W / cm²~100W / cm², irradiation time 120 seconds~360 seconds; the heat curing treatment temperature is set at 80°C~120°C, and the treatment time is 15 minutes~30 minutes.