Ultraviolet light-cured anti-fingerprint coating, preparation method and application thereof

Abstract

The present application relates to the field of paint, disclose a kind of ultraviolet light solidification anti-fingerprint paint and its preparation method, application.The ultraviolet light solidification anti-fingerprint paint includes: photocuring coating mother liquor 90-99 parts, contains double bond fluorine-containing silicon-containing anti-fingerprint acrylic resin 1-10 parts.The coating obtained by the present application coating curing, while ensuring flexibility, with excellent wear and scratch resistance, can greatly improve the long-term anti-fingerprint performance of coating;While the coating has excellent transparency.In addition, the present application coating can be cured by ultraviolet light curing mode, curing speed is fast;And ultraviolet light curing process does not generate heat, especially suitable for temperature-sensitive material;In addition, ultraviolet light curing does not contain solvent or volatile organic compounds, more safe and environmentally friendly.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of coatings, in particular to an ultraviolet light-cured anti-fingerprint coating and a preparation method and application thereof. BACKGROUND

[0002] In the use process of 3C electronic products, the touch panel is easily contaminated by the oil, sweat and other pollutants on the surface of human finger skin in the exposed use state, thereby the fingerprint is contaminated on the surface of the touch panel, which seriously affects the appearance. The fingerprint is different from the general pollutants, and its chemical composition is complex, so the coating on the surface of the touch panel needs to have higher anti-fouling performance. Moreover, electronic products such as mobile phones have a high use frequency in daily life, so the coating surface not only needs to have hydrophobic and oleophobic anti-fouling and anti-fingerprint performance, but also needs to withstand long-term wiping damage from the outside world and maintain long-acting easy-to-clean anti-fingerprint performance.

[0003] In view of this, some researchers introduce the structure of silicon dioxide into the coating by sol-gel method, and they use the low surface energy characteristics and many advantages such as wear resistance and hardness of silicon dioxide to improve the long-lasting anti-fingerprint performance of the coating. However, the 3C products such as mobile phones are prepared from a heat-sensitive substrate, and the high-temperature thermal curing method will cause damage to the heat-sensitive substrate.

[0004] On the other hand, for the touch screen, since the picture needs to be displayed, the anti-fingerprint coating is required to have excellent transparency, so as not to affect the use experience of the product. However, in the prior art, many anti-fingerprint coatings add different anti-fingerprint functional fillers, which have good anti-fingerprint effect, but also affect the transparency of the coating, so further improvement is needed. SUMMARY

[0005] In order to solve the above technical problems, the present application provides an ultraviolet light-cured anti-fingerprint coating and a preparation method and application thereof. The present application introduces fluorine segments and silicon segments into the molecular chain of the acrylic resin at the same time to realize the hydrophobic and oleophobic properties of the coating, so that the coating can reduce fingerprints and other oil residues. At the same time, the anti-fingerprint acrylic resin contains double bonds, which can participate in photo-crosslinking reaction, can firmly fix the functional groups on the coating, can provide excellent wear resistance and scratch resistance while ensuring the flexibility of the coating, and can greatly improve the long-acting anti-fingerprint performance of the coating. The anti-fingerprint acrylic resin containing double bonds, fluorine and silicon can significantly improve the transparency of the coating. The coating of the present application is cured by ultraviolet light curing method, and the curing speed is fast. The ultraviolet curing process does not generate heat, and is particularly suitable for temperature-sensitive substances. In addition, the ultraviolet light curing does not contain solvent or volatile organic compounds, which is safe and environmentally friendly.

[0006] The specific technical scheme of the present application is as follows:

[0007] In a first aspect, the present application provides an ultraviolet light-cured anti-fingerprint coating, which comprises the following raw materials (100 parts in total): 90-99 parts of a light-cured coating mother liquor, and 1-10 parts of a double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin.

[0008] In the present application, the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin serves as the main framework of the coating, which has many advantages such as anti-fingerprint, high strength, wear resistance, corrosion resistance, etc. Specifically, the present application realizes the hydrophobic and oleophobic properties of the coating by simultaneously introducing fluorine segments and silicon segments into the molecular chain of the acrylic resin, so that the coating can reduce fingerprints and other grease residues and is easy to clean. At the same time, through the special design of the monomers and proportions of the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin, excellent wear resistance and scratch resistance can be provided while ensuring the flexibility of the coating, which is crucial for anti-fingerprint coatings as it needs to remain intact in an environment of frequent touching and use.

[0009] On the other hand, compared with conventional fluorine hyperbranched polymers in the prior art, the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin of the present application can significantly improve the transparency of the coating. The reason is that conventional fluorine hyperbranched polymers are prone to form aggregates in the resin matrix, forming an optical heterogeneity region between the two phases, thereby reducing the light transmittance.

[0010] In addition, the coating of the present application contains a light-cured coating mother liquor, which can be cured by ultraviolet light curing. Ultraviolet light curing is fast and can quickly solidify in a short time, which can be applied to high-speed production lines and application scenarios that require instant curing. At the same time, the ultraviolet light curing process does not generate heat, so it will not cause thermal deformation of the coating and the substrate, which makes it particularly suitable for temperature-sensitive materials such as plastic films. In addition, ultraviolet light curing does not require the use of solvents or volatile organic compounds, which can reduce environmental pollution and is beneficial to human health and safety.

[0011] As a preferred embodiment, the synthetic monomers of the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin include: 18-23 parts of methyl methacrylate, 25-30 parts of hydroxyethyl methacrylate, 15-35 parts of an anti-fingerprint functional monomer, and 28-35 parts of isocyanate acrylate.

[0012] The application uses methyl methacrylate, hydroxyethyl methacrylate and anti-fingerprint functional monomers as raw materials, and obtains the anti-fingerprint acrylic resin containing double bonds, fluorine and silicon through free radical random copolymerization under the action of an initiator, then the hydroxyl group contained in the hydroxyethyl methacrylate is added with isocyanate acrylate, the isocyanate group and the hydroxyl group of the two groups are acylated, the double bond functional group is successfully introduced into the anti-fingerprint acrylic resin system, and the anti-fingerprint acrylic resin containing double bonds, fluorine and silicon is prepared. Since the anti-fingerprint acrylic resin contains double bonds, it can participate in photocrosslinking reaction when the coating is ultraviolet cured, so that the functional groups are firmly fixed on the coating, and the long-term anti-fingerprint performance of the coating can be greatly improved.

[0013] Further preferably, the raw materials of the anti-fingerprint acrylic resin containing double bonds, fluorine and silicon include: 18-23 parts of methyl methacrylate, 25-30 parts of hydroxyethyl methacrylate, 15-35 parts of anti-fingerprint functional monomers, 28-35 parts of isocyanate acrylate, 2-5 parts of initiator, 0.5-1 part of catalyst, and the rest of solvent.

[0014] Preferably, the anti-fingerprint functional monomers are methyl methacrylate and tridecafluorooctyl methacrylate.

[0015] The short carbon chain tridecafluorooctyl methacrylate used in the application is easier to degrade than the long carbon chain fluorine-containing acrylate compound, the silicon-containing polymer itself has low toxicity, and can replace the long-chain fluorine-containing polymer with poor biodegradability, and is more friendly to the environment.

[0016] Further preferably, the proportion of methyl methacrylate in the anti-fingerprint functional monomers is 40-80 mol%.

[0017] The present application finds that the ratio of fluorine-containing monomer and silicon-containing monomer in the anti-fingerprint functional monomer has a significant impact on the anti-fingerprint effect of the final coating under long-term wiping damage by the outside world. Specifically: compared with single fluorine-containing coating and single silicon-containing coating, the anti-fouling property of the silicon-containing fluorine-containing coating is better, because when the two components are doped, the interface layer has both the excellent lubricity of siloxane and the excellent hydrophobic and oleophobic properties of fluorine chain segments, and has a synergistic effect. In the process of optimizing the ratio of the two, the present application tried to use 80%, 60% and 40% of the molar fraction of silicon-containing monomers, and found that the anti-fouling performance first increased and then decreased, and the optimal ratio of silicon-containing monomers was 60%. The reason may be that with the excessive fluorine chain segment, the creep performance of the silicon chain segment in the anti-fingerprint acrylic resin is affected. The fluorine alcohol chain segment has the characteristics of high rigidity and strong hydrophobicity, which limits the free rotation and displacement between molecules, resulting in a decrease in the dynamic creep recovery performance of the entire material system. Therefore, under the external load of repeated smearing or wiping, the resilience of the resin coating is weakened, which shows that the durability is damaged, that is, the number of anti-graffiti is reduced. On this basis, increasing the content of the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin in the coating, the results show that the anti-graffiti property of the coating is not significantly improved, and the distribution density of the siloxane chain segment and the fluorine chain segment on the surface of the coating has reached a saturation threshold, and the newly added chain segment cannot find enough free space to embed, so the anti-graffiti property is improved slightly, and the overall cost of the coating is increased.

[0018] As a preferred, the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin, the solvent is selected from ethyl acetate and butyl acetate; the initiator is selected from tert-butyl benzoyl peroxide, di-tert-amyl peroxide and di-tert-butyl peroxide; and the catalyst is selected from dibutyl tin dilaurate and dibutyl tin sulfide.

[0019] As a preferred, the raw materials of the photo-curable coating mother liquor include: trimethylolpropane triacrylate 40-60 parts, epoxy resin 20-30 parts, solvent 15-27 parts, and photo initiator 1-5 parts.

[0020] As a preferred, in the photo-curable coating mother liquor, the epoxy resin is selected from bisphenol A type epoxy acrylate resin and bisphenol epoxy acrylate; the solvent is selected from ethyl acetate and butyl acetate; and the photo initiator is selected from 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone and 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0021] In a second aspect, the present application provides a preparation method of an ultraviolet light-cured anti-fingerprint coating, which specifically includes the following steps:

[0022] 1) Preparation of photo-curable coating mother liquor: uniformly mix bisphenol A type epoxy acrylate resin, trimethylolpropane triacrylate, photo initiator and solvent to obtain a photo-curable coating mother liquor.

[0023] 2) Preparation of the anti-fingerprint acrylic resin containing double bond, fluorine and silicon: add methyl methacrylate, hydroxyethyl methacrylate and initiator into solvent, mix well, heat and react, add anti-fingerprint functional monomer and catalyst, continue to react, concentrate, add the concentrated solution into purification liquid to precipitate, dry; mix the obtained product with solvent, heat, add isocyanate acrylate dropwise, add catalyst to react, concentrate, add the concentrated solution into purification liquid to precipitate, dry.

[0024] The anti-fingerprint acrylic resin containing double bond, fluorine and silicon is prepared by free radical random copolymerization reaction: methyl methacrylate, hydroxyethyl methacrylate and anti-fingerprint functional monomer are dissolved in solvent to form a uniform mixture, then the double bond in the monomers is attacked by free radicals under the action of initiator to generate free radical intermediates. These free radical intermediates continuously react with monomer molecules to generate longer and longer polymer chains to obtain the anti-fingerprint acrylic resin containing fluorine and silicon. Isocyanate acrylate is selected as the double bond monomer to synthesize the anti-fingerprint acrylic resin containing double bond, fluorine and silicon by acylation reaction between hydroxyl and isocyanate group, so that the anti-fingerprint acrylic resin participates in photocrosslinking reaction together when the coating is cured by ultraviolet light, and the anti-fouling segment is more firmly fixed on the surface of the coating. The preparation method of the anti-fingerprint acrylic resin containing double bond, fluorine and silicon is completed in two steps, which is simple and easy to operate, has high synthesis conversion rate, and has wide industrialization prospect.

[0025] As preferred, in step 2), the concentration and precipitation are repeated for multiple times.

[0026] As preferred, in step 2), the purification liquid is selected from n-hexane, n-pentane, n-heptane and n-octane.

[0027] In a third aspect, the application provides application of the above-mentioned ultraviolet light cured anti-fingerprint coating in preparation of ultraviolet light cured anti-fingerprint coating layer, which comprises: mixing the anti-fingerprint acrylic resin containing double bond, fluorine and silicon with light cured coating mother liquor, coating on the surface of a substrate, drying, and then curing by ultraviolet light irradiation to obtain the ultraviolet light cured anti-fingerprint coating layer.

[0028] As preferred, the drying time is 50-70℃ for 1-5 min.

[0029] Compared with the prior art, the application has the following beneficial effects:

[0030] (1) The present application realizes the hydrophobic and oleophobic properties of the coating by simultaneously introducing fluorine segments and silicon segments into the molecular chain of the acrylic resin, so that the coating can reduce fingerprints and other grease residues and is easy to clean. At the same time, the anti-fingerprint acrylic resin of the present application introduces double bonds through acylation reaction, so that it can participate in photo-crosslinking reaction together, firmly fixing the functional groups on the coating, which can provide excellent wear resistance and scratch resistance while ensuring the flexibility of the coating, thereby greatly improving the long-term anti-fingerprint performance of the coating.

[0031] (2) The anti-fingerprint acrylic resin containing double bonds, fluorine and silicon of the present application can significantly improve the transparency of the coating compared with conventional fluorine hyperbranched polymers.

[0032] (3) The coating of the present application can be cured by ultraviolet light curing method, which has fast curing speed and can be applied to high-speed production lines and application scenarios that require instant curing. At the same time, the ultraviolet light curing process does not generate heat, so it will not cause thermal deformation of the coating and the substrate, and is particularly suitable for temperature-sensitive materials. In addition, ultraviolet light curing does not require the use of solvents or volatile organic compounds, which can reduce environmental pollution and is beneficial to human health and safety.

[0033] (4) The present application selects acrylic resin as the material matrix, and the prepared coating has high light transmittance, low haze, strong yellowing resistance and aging resistance, which can meet the daily needs of 3C products. DETAILED DESCRIPTION

[0034] The present application will be further described below in conjunction with examples.

[0035] General examples

[0036] First, an ultraviolet light curing anti-fingerprint coating, which includes the following raw materials (total amount is 100 parts) by weight: photocuring coating mother liquor 90-99 parts, anti-fingerprint acrylic resin containing double bonds, fluorine and silicon 1-10 parts. Among them, the synthesis monomer of the anti-fingerprint acrylic resin containing double bonds, fluorine and silicon includes: methyl methacrylate 18-23 parts, hydroxyethyl methacrylate 25-30 parts, anti-fingerprint functional monomer 15-35 parts, isocyanate acrylate 28-35 parts; the anti-fingerprint functional monomer is methyl methacrylate and tridecafluorooctyl methacrylate.

[0037] In some preferred embodiments, the proportion of methyl methacrylate in the anti-fingerprint functional monomer is 40-80 mol%.

[0038] In some preferred embodiments, the raw materials of the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin include: methyl methacrylate 18-23 parts, hydroxyethyl methacrylate 25-30 parts, anti-fingerprint functional monomer 15-35 parts, isocyanate acrylate 28-35 parts, initiator 2-5 parts, catalyst 0.5-1 part, and solvent in the remaining amount.

[0039] In some more preferred embodiments, the double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin, the solvent is selected from ethyl acetate and butyl acetate; the initiator is selected from tert-butyl benzoyl peroxide, di-tert-amyl peroxide and di-tert-butyl peroxide; and the catalyst is selected from dibutyltin dilaurate and dibutyltin sulfide.

[0040] In some preferred embodiments, the raw materials of the photocuring coating mother liquor include: trimethylolpropane triacrylate 40-60 parts, epoxy resin 20-30 parts, solvent 15-27 parts, and photoinitiator 1-5 parts.

[0041] In some more preferred embodiments, the epoxy resin in the photocuring coating mother liquor is selected from bisphenol A type epoxy acrylic resin and bisphenol epoxy acrylate; the solvent is selected from ethyl acetate and butyl acetate; and the photoinitiator is selected from 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone and 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0042] Secondly, a preparation method of an ultraviolet light curing anti-fingerprint coating, which specifically comprises the following steps:

[0043] 1) Preparation of photocuring coating mother liquor: uniformly mix bisphenol A type epoxy acrylic resin, trimethylolpropane triacrylate, photoinitiator and solvent to obtain photocuring coating mother liquor.

[0044] 2) Preparation of the anti-fingerprint acrylic resin containing double bond, fluorine and silicon: pour the solvent into a four-necked round-bottom flask, continuously pass nitrogen and warm the system to the specified temperature and appear reflux phenomenon; mix 18-23 parts by weight of methyl methacrylate, 25-30 parts by weight of hydroxyethyl methacrylate and 2-5 parts by weight of initiator and slowly drop into the four-necked flask through a constant-pressure four-fluorine funnel, the drop time is controlled within 2.5-3 h; after the end of the drop of the mixture, it is incubated for 8-10 h, and the initiator is supplemented every 2-4 h during the incubation period, and the resin is cooled and discharged after the reaction is completed; add 15-35 parts by weight of anti-fingerprint functional monomer to the synthesized resin. Drop 0.5-1 parts by weight of catalyst at 70-90°C; then concentrate the synthesized anti-fingerprint acrylic resin by rotary evaporation, slowly pour the concentrated liquid into the purification liquid for precipitation, repeat the precipitation and dissolution for several times to obtain the purified product, and dry in a vacuum oven at 70-90°C. Add the anti-fingerprint acrylic resin and the solvent mixture to a four-necked round-bottom flask, start stirring and heating, heat to 70-90°C, then slowly drop 28-35 parts by weight of isocyanate ethyl acrylate monomer solution, and the drop time is controlled within 30 min. After the end of the drop, add 0.5-1 parts by weight of catalyst, incubate for 8-10 h, and discharge after the reaction is completed. Then concentrate the synthesized anti-fingerprint acrylic resin containing double bond, fluorine and silicon by rotary evaporation, slowly pour the concentrated liquid into the purification liquid for precipitation, repeat the precipitation and dissolution for several times to obtain the purified product, and dry in a vacuum oven at 70-90°C to obtain the anti-fingerprint acrylic resin containing double bond, fluorine and silicon.

[0045] In some preferred embodiments, in step 2), the purification liquid is selected from n-hexane, n-pentane, n-heptane and n-octane.

[0046] Finally, a preparation method of an ultraviolet light cured anti-fingerprint coating, which comprises: mixing the anti-fingerprint acrylic resin containing double bond, fluorine and silicon with a light-cured coating mother liquor, coating on the surface of a substrate, drying, and then curing by ultraviolet light irradiation to obtain an ultraviolet light cured anti-fingerprint coating.

[0047] In some preferred embodiments, the drying time is 50-70°C for 1-5 min.

[0048] Specific examples and comparative examples

[0049] Preparation example of anti-fingerprint acrylic resin:

[0050] Comparative example 1 (anti-fingerprint acrylic resin containing double bond and silicon)

[0051] Into a four-necked round bottom flask, 20 g of butyl acetate was poured, nitrogen was continuously introduced, and the system was warmed to the specified temperature and reflux was observed; 20 g of methyl methacrylate, 35.75 g of hydroxyethyl methacrylate, and 2 g of tert-butyl benzoyl peroxide were mixed and slowly added to the four-necked flask through a constant pressure four-fluoride funnel, and the dropping time was 3 h; after the completion of the addition of the mixture, it was incubated for 9 h, and 0.5 g of tert-butyl benzoyl peroxide was added every 3 h during the incubation period, a total of twice, and the resin was cooled and discharged after the reaction was completed; 23.7 g of methyl methacrylate was added to the synthesized resin. At 80°C, 0.5 g of dibutyltin dilaurate was added dropwise; the synthesized silicon-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution for 3 times, and was placed in a vacuum oven at 80°C for drying. Into a four-necked round bottom flask, 20 g of silicon-containing anti-fingerprint acrylic resin was mixed with 80 g of butyl acetate, stirring and heating was started, the rotation speed was 100 rpm, heating to 80°C was constant, then 31 g of isocyanate ethyl acrylate solution with a monomer concentration of 15% was slowly added dropwise, and the dropping time was 30 min. After the completion of the addition, 0.5 g of dibutyltin dilaurate was added, and incubated for 9 h, after the reaction was completed, the resin was cooled and discharged. The synthesized double bond-containing silicon-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution for several times, and was placed in a vacuum oven at 80°C for drying, to obtain the double bond-containing silicon-containing anti-fingerprint acrylic resin.

[0052] Comparative Example 2 (double bond-containing fluorine-containing anti-fingerprint acrylic resin)

[0053] Into a four-necked round bottom flask, 20 g of butyl acetate was poured, nitrogen was continuously introduced, and the system was warmed to the specified temperature and reflux was observed; 20 g of methyl methacrylate, 35.75 g of hydroxyethyl methacrylate, and 2 g of tert-butyl peroxybenzoate were mixed and slowly added to the four-necked flask through a constant pressure four-fluoride funnel, and the dropping time was 3 h; after the mixture was added, it was incubated for 9 h, and 0.5 g of tert-butyl peroxybenzoate was added every 3 h during the incubation period, a total of twice, and the resin was cooled and discharged after the reaction was completed; 41.7 g of methyl methacrylate was added to the synthesized resin. At 80°C, 0.5 g of dibutyltin dilaurate was added dropwise; the synthesized fluorine-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution 3 times, and was placed in a 80°C vacuum oven for drying. Into a four-necked round bottom flask, 20 g of fluorine-containing anti-fingerprint acrylic resin was mixed with 80 g of butyl acetate, stirring was started and heating was started, the rotation speed was 100 rpm, heating was started to 80°C, and then 31 g of isocyanate acrylate solution with a monomer concentration of 15% was slowly added dropwise, and the dropping time was 30 min. After the addition was completed, 0.5 g of dibutyltin dilaurate was added, and incubated for 9 h. After the reaction was completed, the resin was cooled and discharged. The synthesized double-bond-containing fluorine-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution several times, and was placed in a 80°C vacuum oven for drying, to obtain a double-bond-containing fluorine-containing anti-fingerprint acrylic resin.

[0054] Example 1 (double-bond-containing fluorine-containing silicon-containing anti-fingerprint acrylic resin, 40 mol% silicon)

[0055] Into a four-necked round bottom flask, 20 g of butyl acetate was poured, nitrogen was continuously introduced, and the system was warmed to the specified temperature and reflux was observed; 20 g of methyl methacrylate, 35.75 g of hydroxyethyl methacrylate, and 2 g of tert-butyl peroxybenzoate were mixed and slowly added to the four-necked flask through a constant pressure four-fluoride funnel, and the dropping time was 3 h; after the mixture was added, it was incubated for 9 h, and 0.5 g of tert-butyl peroxybenzoate was added every 3 h during the incubation period, a total of twice, and the resin was cooled and discharged after the reaction was completed; 25.02 g of tridecafluorooctyl methacrylate and 9.48 g of silicon methacrylate were added to the synthesized resin. At 80°C, 0.5 g of dibutyltin dilaurate was added; the synthesized fluorine and silicon-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution 3 times, and was dried in a vacuum oven at 80°C. Into a four-necked round bottom flask, 20 g of fluorine and silicon-containing anti-fingerprint acrylic resin and 80 g of butyl acetate mixture were added, stirring and heating were started, the rotation speed was 100 rpm, heating was started to 80°C, and then 31 g of isocyanate acrylate solution with a monomer concentration of 15% was slowly added, and the dropping time was 30 min. After the addition was completed, 0.5 g of dibutyltin dilaurate was added, and incubated for 9 h. After the reaction was completed, the resin was cooled and discharged. The synthesized double bond-containing fluorine and silicon-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution several times, and was dried in a vacuum oven at 80°C, to obtain a double bond-containing fluorine and silicon-containing anti-fingerprint acrylic resin (40 mol% silicon).

[0056] Example 2 (Double bond-containing fluorine and silicon-containing anti-fingerprint acrylic resin, 60 mol% silicon)

[0057] Into a four-necked round bottom flask, 20 g of butyl acetate was poured, nitrogen was continuously introduced, and the system was warmed to the specified temperature and reflux was observed; 20 g of methyl methacrylate, 35.75 g of hydroxyethyl methacrylate, and 2 g of tert-butyl peroxybenzoate were mixed and slowly added to the four-necked flask through a constant pressure four-fluoride funnel, and the dropping time was 3 h; after the mixture was added, it was incubated for 9 h, and 0.5 g of tert-butyl peroxybenzoate was added every 3 h during the incubation period, a total of twice, and the resin was cooled and discharged after the reaction was completed; 16.68 g of tridecafluorooctyl methacrylate and 14.22 g of silicon methacrylate were added to the synthesized resin. At 80°C, 0.5 g of dibutyltin dilaurate was added; the synthesized fluorine and silicon-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution 3 times, and was dried in a vacuum oven at 80°C. Into a four-necked round bottom flask, 20 g of fluorine and silicon-containing anti-fingerprint acrylic resin and 80 g of butyl acetate mixture were added, stirring and heating were started, the rotation speed was 100 rpm, heating was started to 80°C, and then 31 g of isocyanate ethyl acrylate solution with a monomer concentration of 15% was slowly added, and the dropping time was 30 min. After the addition was completed, 0.5 g of dibutyltin dilaurate was added, and incubated for 9 h. After the reaction was completed, the resin was cooled and discharged. The synthesized double bond-containing fluorine and silicon-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated liquid was slowly poured into n-hexane for precipitation, and the purified product was obtained by repeated precipitation and dissolution several times, and was dried in a vacuum oven at 80°C to obtain a double bond-containing fluorine and silicon-containing anti-fingerprint acrylic resin (60 mol% silicon).

[0058] Example 3 (double bond-containing fluorine and silicon-containing anti-fingerprint acrylic resin, 80 mol% silicon)

[0059] Into a four-necked round bottom flask, 20 g of butyl acetate was poured, nitrogen was continuously introduced, and the system was warmed to the specified temperature and reflux was observed; 20 g of methyl methacrylate, 35.75 g of hydroxyethyl methacrylate, and 2 g of tert-butyl peroxybenzoate were mixed and slowly added to the four-necked flask through a constant pressure fluorotetra funnel, and the dropping time was 3 h; after the mixture was added, it was incubated for 9 h, and 0.5 g of tert-butyl peroxybenzoate was added every 3 h during the incubation period, a total of twice, and the resin was cooled and discharged after the reaction was completed; 8.34 g of tridecafluorooctyl methacrylate and 18.96 g of silicon-containing methacrylate were added to the synthesized resin. At 80°C, 0.5 g of dibutyltin dilaurate was added dropwise; the synthesized fluorine-containing and silicon-containing anti-fingerprint acrylic resin was concentrated by rotary evaporation, and the concentrated solution was slowly poured into n-hexane for precipitation. The purified product was obtained by repeated precipitation and dissolution for 3 times, and was dried in a vacuum oven at 80°C. In a four-necked round bottom flask, 20 g of the fluorine-containing and silicon-containing anti-fingerprint acrylic resin and 80 g of a butyl acetate mixture were mixed, stirring was started, and heating was started at a speed of 100 rpm. The temperature was raised to 80°C and then maintained, and then 31 g of a 15% isocyanate ethyl acrylate solution was slowly added dropwise over a period of 30 min. After the addition was completed, 0.5 g of dibutyltin dilaurate was added, and the mixture was incubated for 9 h. After the reaction was completed, the resin was cooled and discharged. The synthesized double-bond-containing, fluorine-containing, and silicon-containing anti-fingerprint acrylic resin (80 mol% silicon) was obtained by concentrating the product by rotary evaporation, slowly pouring the concentrated solution into n-hexane for precipitation, and repeatedly precipitating and dissolving the product several times to obtain a purified product, which was dried in a vacuum oven at 80°C.

[0060] Coating preparation example:

[0061] (1) 35 g of trimethylolpropane triacrylate, 25 g of bisphenol A epoxy acrylate resin, 17 g of ethyl acetate, 20 g of butyl acetate, and 3 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone were mixed and stirred in a beaker at a speed of 180 rpm for 10 min to obtain a photocuring coating mother liquor.

[0062] (2) 95 g of the photocuring coating mother liquor was taken, and 5 g of the double-bond-containing, silicon-containing anti-fingerprint acrylic resin prepared in Comparative Example 1 was added thereto. After stirring at a speed of 180 rpm for 10 min, the mixture was baked in a 60°C oven for 5 min to remove the solvent. After baking, the mixture was cured in a photocuring machine using a mercury lamp light source to obtain a silicon-containing ultraviolet photocuring anti-fingerprint coating.

[0063] Comparative Example 4

[0064] The difference between Example 4 and Comparative Example 3 is that in step (2), 5 g of the double-bond containing fluorine-containing silicon-containing anti-fingerprint acrylic resin (40 mol% silicon) prepared in Example 1 is used to replace the 5 g of the double-bond containing silicon-containing anti-fingerprint acrylic resin prepared in Comparative Example 1, and the light-cured coating mother liquor is added, and the remaining steps and materials and compositions are consistent with Comparative Example 3.

[0065] The difference between Example 4 and Comparative Example 3 is that in step (2), 5 g of the double-bond containing fluorine-containing silicon-containing anti-fingerprint acrylic resin (40 mol% silicon) prepared in Example 1 is used to replace the 5 g of the double-bond containing silicon-containing anti-fingerprint acrylic resin prepared in Comparative Example 1, and the light-cured coating mother liquor is added, and the remaining steps and materials and compositions are consistent with Comparative Example 3.

[0066] The difference between Example 4 and Comparative Example 3 is that in step (2), 5 g of the double-bond containing fluorine-containing silicon-containing anti-fingerprint acrylic resin (40 mol% silicon) prepared in Example 1 is used to replace the 5 g of the double-bond containing silicon-containing anti-fingerprint acrylic resin prepared in Comparative Example 1, and the light-cured coating mother liquor is added, and the remaining steps and materials and compositions are consistent with Comparative Example 3.

[0067] The difference between Example 4 and Comparative Example 3 is that in step (2), 5 g of the double-bond containing fluorine-containing silicon-containing anti-fingerprint acrylic resin (40 mol% silicon) prepared in Example 1 is used to replace the 5 g of the double-bond containing silicon-containing anti-fingerprint acrylic resin prepared in Comparative Example 1, and the light-cured coating mother liquor is added, and the remaining steps and materials and compositions are consistent with Comparative Example 3.

[0068] Comparative Example 5

[0069] The difference between Example 4 and Comparative Example 3 is that in step (2), 5 g of the double-bond containing fluorine-containing silicon-containing anti-fingerprint acrylic resin (40 mol% silicon) prepared in Example 1 is used to replace the 5 g of the double-bond containing silicon-containing anti-fingerprint acrylic resin prepared in Comparative Example 1, and the light-cured coating mother liquor is added, and the remaining steps and materials and compositions are consistent with Comparative Example 3.

[0070] Comparative Example 6

[0071] The difference between Example 4 and Comparative Example 3 is that in step (2), 5 g of the double-bond containing fluorine-containing silicon-containing anti-fingerprint acrylic resin (40 mol% silicon) prepared in Example 1 is used to replace the 5 g of the double-bond containing silicon-containing anti-fingerprint acrylic resin prepared in Comparative Example 1, and the light-cured coating mother liquor is added, and the remaining steps and materials and compositions are consistent with Comparative Example 3.

[0072] Performance Test

[0073] The UV-curable anti-fingerprint coatings prepared in each example and the coatings prepared in each comparative example were respectively tested for hardness, adhesion, anti-graffiti property, water contact angle and other properties. The hardness test was performed according to GB / T 6739, and the results were evaluated as follows: paint film scratch; the adhesion test was performed according to GB / T 9286, with a spacing of 1 mm; the anti-graffiti test was performed by writing on the surface of the coating with an oil-based pen and wiping. Two points at different distances were selected on the surface of the coating, then three straight lines were drawn between the two points, and finally the surface was wiped with a dust-free cloth. The writing and wiping were repeated until the ink could not be removed, and the number of times was recorded. The water contact angle test was obtained by DSA 10-MK2 drop analyzer (Kruss, Germany), and the volume of the droplet used in the experiment was 5 μL. The light transmittance was determined according to GB / T 2410-2008; the test environment temperature was 25 °C; and the relative humidity was 70% RH.

[0074] Table 1: Performance test results of products in each example and each comparative example

[0075]

[0076]

[0077] From the comparison of the data in the above table, it can be seen that:

[0078] Comparative Example 4 used a double-bond-containing fluorine-containing anti-fingerprint acrylic resin to replace the double-bond-containing silicon-containing anti-fingerprint acrylic resin in Comparative Example 3. Since the relatively hard structure of silicone in the system was replaced by the relatively soft structure of fluorine, the hardness of the coating was reduced, but the anti-graffiti property and water contact angle of the coating were improved, indicating that the coating with the same amount of fluorine-containing structure has better anti-staining property than the coating with silicon-containing structure.

[0079] Example 4-6 used different silicon component ratio of double bond containing fluorine containing silicon anti-fingerprint acrylic resin to replace the double bond containing silicon anti-fingerprint acrylic resin in Comparative Example 3, the silicone structure and fluorine structure in the system were doped, compared with the coating containing only silicon structure, the hardness was reduced, but the anti-fouling property of the coating was first increased and then decreased with the increase of the proportion of fluorine, wherein the double bond containing fluorine containing silicon anti-fingerprint acrylic resin prepared in Example 2 (60 mol% silicon) had the best effect, the reason may be that when the two are doped, the interface layer has the excellent lubricity of siloxane and the excellent hydrophobic and oleophobic properties of fluorine segment, which has a synergistic effect, and the effect is best. With the excessive fluorine segment, the microstructure and dynamic behavior of the anti-fingerprint acrylic resin are affected, especially its unique creep performance. Due to the characteristics of high rigidity and strong hydrophobicity, the fluorine segment restricts the free rotation and displacement between molecules. When the fluorine content gradually increases, these special segments begin to occupy a larger proportion in the molecular structure, enhancing the local rigidity and reducing the flexibility and creep ability of the silicon segment. Similar to mixing hard lines in soft rubber belts, the original smooth deformation process is hindered, resulting in a decrease in the dynamic creep recovery performance of the entire material system. This will directly reflect on the number of graffiti resistance. Under the external load of repeated painting or wiping, the resilience of the resin coating is weakened, which shows that the durability is damaged, that is, the number of graffiti resistance is reduced.

[0080] In Comparative Example 5, the amount of double bond containing fluorine containing silicon anti-fingerprint acrylic resin (60 mol% silicon) was increased from 5% to 10%, but from the test results, the anti-graffiti property and water contact angle of the coating did not have much improvement, because when the silanol and fluorine alcohol are grafted to a certain critical value, the siloxane segment and fluorine segment on the surface of the coating have reached a sufficient enrichment state, and their distribution density is close to the saturation threshold. New segments have little free space to embed, so even if the doping ratio of silanol and fluorine alcohol is further increased, the contribution to the overall performance of the surface layer of the coating is also minimal. However, due to the doubling of the amount of anti-fingerprint acrylic resin, the cost of the coating will increase.

[0081] In Comparative Example 6, fluorine hyperbranched polymer was used to replace the same amount of self-made functional acrylic resin, and from the test results, the light transmittance was obviously decreased, because the compatibility of fluorine hyperbranched polymer is lower than that of self-made functional acrylic resin, which will be unevenly distributed in the resin matrix, forming aggregation, and forming optical heterozone between the two phases, reducing the light transmittance.

[0082] The raw materials and equipment used in the present application are conventional raw materials and equipment in the art unless otherwise specified; the methods used in the present application are conventional methods in the art unless otherwise specified.

[0083] The above is only the preferred embodiment of the present application, and does not limit the present application, and any simple modification, change and equivalent transformation of the above embodiment according to the technical essence of the present application still belongs to the protection scope of the technical scheme of the present application.

Claims

1. A method for preparing a UV-curable anti-fingerprint coating, characterized in that... include: 1) Mix 20-30 parts of bisphenol A type epoxy acrylate resin, 40-60 parts of trimethylolpropane triacrylate, 1-5 parts of photoinitiator, and 15-27 parts of solvent to obtain a light-curing coating mother liquor. 2) Add 18-23 parts of methyl methacrylate, 25-30 parts of hydroxyethyl methacrylate, and 2-5 parts of initiator to the solvent, mix well, heat and react. Add 15-35 parts of anti-fingerprint functional monomer and catalyst to continue the reaction. Concentrate, add the concentrate to the purification solution to precipitate, and dry. Mix the obtained product with the solvent, heat, add 28-35 parts of ethyl isocyanate acrylate dropwise, add catalyst to react, concentrate, add the concentrate to the purification solution to precipitate, and dry. The total amount of catalyst is 0.5-1 part. The anti-fingerprint functional monomers are silicone methacrylate and tridecafluorooctyl methacrylate. The proportion of silicone methacrylate is 40-80 mol%. The coating contains 90-99 parts of UV-curable coating mother liquor and 1-10 parts of anti-fingerprint acrylic resin containing double bonds, fluorine, and silicon. The above raw materials are listed in parts by weight.

2. The preparation method according to claim 1, characterized in that: The solvent is selected from ethyl acetate and butyl acetate.

3. The preparation method according to claim 1, characterized in that: The initiator is selected from tert-butyl peroxide, di-tert-amyl peroxide, and di-tert-butyl peroxide.

4. The preparation method according to claim 1, characterized in that: The catalyst is selected from dibutyltin dilaurate and dibutyltin sulfide.

5. The preparation method according to claim 1, characterized in that: The photoinitiator is selected from 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholin-1-propanone and 2-hydroxy-2-methyl-1-phenyl-1-propanone.

6. The preparation method according to claim 1, characterized in that: In step 2), the precipitation process is repeated multiple times.

7. The preparation method according to claim 1, characterized in that: In step 2): the purification solution is selected from n-hexane, n-pentane, n-heptane and n-octane.

8. The application of the UV-curable anti-fingerprint coating obtained by the preparation method according to any one of claims 1-7 in the preparation of UV-curable anti-fingerprint coatings, characterized in that... include: A double-bonded, fluorine-containing, and silicon-containing anti-fingerprint acrylic resin is mixed with a UV-curable coating masterbatch, coated onto the substrate surface, dried, and then cured by UV irradiation to obtain a UV-curable anti-fingerprint coating.

9. The application according to claim 8, characterized in that: The drying temperature is 50-70℃, and the time is 1-5 minutes.

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