A triple-cured pine oil-encapsulated UV coating, and a preparation method and application thereof

Abstract

The application belongs to the technical field of paint, and discloses a triple-curing pine wood oil sealing UV paint, a preparation method and application thereof, which comprises the following raw materials: cationic UV resin, polyurethane acrylate oligomer, active monomer, polymerization inhibitor, cationic photoinitiator, free radical photoinitiator and catalyst; the active monomer comprises at least one of a double bond-containing acrylate monomer, a vinyl ether monomer and an oxetane monomer; and the catalyst comprises at least one of AlCl3, SbCl3, AlBr3, AlCl3(C2H5)O and BF3(C2H5)O. The paint film of the triple-curing pine wood oil sealing UV paint has a good oil sealing effect on a pine wood base material.

Description

Technical Field

[0001] This invention belongs to the field of UV-curable coatings, and specifically relates to a triple-curing UV coating for sealing pine wood, its preparation method, and its application. Background Technology

[0002] Pine wood is a coniferous plant with characteristics such as a pine scent, pale yellow color, numerous knots, rapid response to atmospheric temperature changes, easy swelling, and extreme difficulty in natural air drying. Therefore, it requires artificial processing, such as drying, degreasing to remove organic compounds, bleaching to unify the color, and neutralizing the wood's properties to prevent warping before it can be used. With its simple and unadorned texture, lifelike grain, and pure and bright color, pine wood decorates the home environment with elegance, purity, and harmony with nature. Therefore, pine furniture has been designated as environmentally friendly furniture by the United Nations Department of Humanitarian Affairs.

[0003] In recent years, a large amount of furniture has been made from pine. At the same time, a significant portion of children's furniture and toys are also made from pine. During the manufacturing process, pine furniture and toys are coated with paint for surface protection and decoration. However, because pine contains a large amount of oil, even if the pine boards used for furniture making have undergone degreasing treatment, oil will still seep out in high-temperature environments. This seeping oil can cause the paint film on the pine furniture surface to blister or even peel off, seriously affecting the product's appearance and quality.

[0004] Pine resin consists of approximately 30% turpentine and 70% rosin. Turpentine's main components are α-pinene and β-pinene, and it is liquid at room temperature. Rosin is a transparent, brittle solid natural resin, a relatively complex mixture composed of resin acids (abscisic acid, piratic acid), small amounts of fatty acids, pinene anhydride, and neutral substances. The main component of rosin is resin acid, accounting for about 90%, with the molecular formula C2. 19 H 29 COOH, molecular weight 302.46. Resin acid is the most representative rosin acid, an unsaturated acid containing conjugated double bonds. It strongly absorbs ultraviolet light and can spontaneously oxidize or undergo induced oxidation in air. Rosin appears pale yellow to pale brown, with a vitreous luster and a turpentine odor. Its density is 1.060–1.085 g / cm³. 3 Melting point: 110–135℃; softening point (ring and ball method): 72–76℃; boiling point: approximately 300℃ (0.67 kPa); glass transition temperature (Tg): 30–38℃; refractive index: 1.5453; flash point (open cup): 216℃; ignition point: approximately 480–500℃. It oxidizes easily in air, darkening in color.

[0005] UV curing refers to the process by which a substance transforms from a low-molecular-weight substance to a high-molecular-weight substance under ultraviolet light irradiation, unlike ordinary heat curing, natural curing, and crosslinking agent curing. Its curing mechanism is as follows: light irradiation causes the photoinitiator to decompose into free radicals or anions and cations, which further initiate the polymerization reaction of monomers containing active groups, polymerizing into an insoluble and infusible solid coating film. Compared with traditional curing technologies, UV curing technology saves energy, cures quickly, produces coatings with good performance, and is suitable for large-scale industrial production. Furthermore, UV-cured materials contain no or only a small amount of volatile organic compounds (VOCs) during the curing process, earning it the reputation of "green technology." Because UV coatings using UV curing technology have the above advantages, during the curing process in a UV curing machine, the exothermic reaction and UV irradiation cause a temperature rise in both the coating film and the substrate. When the temperature reaches 70℃, close to the softening point of pine resin, the resin will seep out of the wood in a liquid state. Therefore, when applying UV coatings to pine substrates and curing them, the temperature rise of the coating film and substrate can easily cause the pine wood to "ooze oil," leading to blistering of the coating film and even delamination, seriously affecting product quality. This problem greatly limits the widespread application of UV coatings in pine furniture.

[0006] Therefore, it is urgent to develop a UV coating for sealing pine wood to prevent the pine wood from "oozing oil" during the curing process of UV coating on pine wood substrates, which would then cause the paint film to blister and peel off. Summary of the Invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a triple-curing pine wood sealing UV coating, which can solve the problem of "oil seepage" on pine wood substrates during the UV coating curing process and baking test.

[0008] The first aspect of the present invention provides a triple-curing pine wood sealing UV coating, comprising the following raw materials: cationic UV resin, polyurethane acrylate oligomer, active monomer, polymerization inhibitor, cationic photoinitiator, free radical photoinitiator, and catalyst;

[0009] The active monomers include at least one of the following: acrylate monomers containing double bonds, vinyl ether monomers, and oxetane monomers;

[0010] The catalyst includes at least one of AlCl3, SbCl3, AlBr3, AlCl3(C2H5)O and BF3(C2H5)O.

[0011] This invention proposes that the epoxy groups of the cationic UV resin can undergo a condensation reaction with the carboxyl groups of the resin acids in pine wood, thereby fixing the resin acids. When the cationicly cured UV coating undergoes cationic polymerization initiated by ultraviolet light, it can simultaneously initiate the polymerization of α-pinene, β-pinene, and resin acids in the resin. The catalyst in this invention is Lewis acid, which can serve as a catalyst for the cationic polymerization of α-pinene, β-pinene, and resin acids in the resin. When the UV coating is applied to the surface of the pine wood substrate, it can initiate a polymerization reaction between the resin on the surface and inside the pine wood, and also a polymerization reaction with the UV coating. After the resin forms a polymer, its softening point can be increased to over 150°C, thus solving the problem of resin softening at 70°C and seeping out of the substrate, causing paint film defects such as "oil seepage." Furthermore, the polymerized resin itself becomes a sealant for the pine wood surface. The polymerization of resin and UV coating forms a whole; the polymerized resin can act as an anchor for the paint film to penetrate the substrate, improving the adhesion between the paint film and the wood, further enhancing the sealing effect.

[0012] According to some preferred embodiments of the present invention, the acid value of the active monomer is <5.

[0013] In this invention, acrylate monomers, vinyl ether monomers, or oxetane monomers containing double bonds are added as active monomers to the polymerization system, which can improve the rate and efficiency of the polymerization reaction and enable low-temperature, high-activity polymerization reactions.

[0014] In this application, the ratio of the sum of the weight parts of the cationic UV resin, the vinyl ether monomer, and the oxetane monomer to the weight parts of the catalyst is 100:1 to 300:1.

[0015] Under the preferred weight ratio, the catalyst can catalyze the cationic polymerization of α-pinene, β-pinene and resin acid in rosin, and can also make the UV coating stable for storage. If the catalyst addition ratio is increased, the storage stability of the UV coating will deteriorate.

[0016] According to some preferred embodiments of the present invention, the acrylate monomers in the active monomers are at least one of SM623 and SM631 from Sanmu Company, and EM221, EM235, EM242 and 6420 from Changxing Company.

[0017] According to some preferred embodiments of the present invention, the vinyl ether monomer is at least one of VM-3510, VM-3520, VM-3530 and VM-3540 from Shenzhen Youyang Company.

[0018] According to some preferred embodiments of the present invention, the oxobutane monomer is at least one of GR-OTX-1, GR-OTX-2, GR-OTX-3, GR-OTX-4, GR-OTX-5, GR-OTX-6, GR-OTX-9 and GR-OTX-11 from Hubei Gurun Technology Co., Ltd.

[0019] According to some embodiments of the present invention, the triple-cured pine wood sealing UV coating comprises, by weight, the following raw materials: 30.0 to 45.0 parts of cationic UV resin, 5.0 to 20.0 parts of polyurethane acrylate oligomer, 15.0 to 25.0 parts of active monomer, 0.01 to 0.5 parts of polymerization inhibitor, 1.0 to 3.0 parts of cationic photoinitiator, 0.5 to 2.0 parts of free radical photoinitiator, and 0.2 to 0.4 parts of catalyst.

[0020] According to some embodiments of the present invention, the triple-curing pine wood sealing UV coating further includes at least one of the following raw materials: talc, defoamer, leveling agent and wetting agent.

[0021] According to some embodiments of the present invention, the triple-curing pine wood sealing UV coating further includes the following raw materials: talc, defoamer, leveling agent and wetting agent. By weight, the triple-curing pine wood sealing UV coating includes the following raw materials: 30.0-45.0 parts of cationic UV resin, 15.0-30.0 parts of talc, 0.1-0.3 parts of defoamer, 0.1-0.3 parts of leveling agent and 0.1-0.4 parts of wetting agent.

[0022] According to some embodiments of the present invention, the polyurethane acrylate oligomer is an aliphatic polyurethane acrylate oligomer with an acid value <5 and not higher than hexafunctionality.

[0023] In this invention, the use of aliphatic polyurethane acrylate oligomers with a functionality not exceeding six avoids excessive shrinkage of the paint film, thereby helping to achieve good adhesion, flexibility and chemical resistance of the coating to the wood surface, thus improving the durability and protective effect of the coating.

[0024] According to some embodiments of the present invention, the cationic UV resin includes ion-hybrid UV resins with a cationic acid value <5, alicyclic oxide resins, and epoxy oligomer resins.

[0025] According to some preferred embodiments of the present invention, the cationic UV resin is at least one of IGM's Omnilane OC1005, Omnilane OC2005, Omnilane OC3005, Shenzhen Youyang's U-9100A, U-9100B, U-9101, U-9103, U-9200, U-9210, U-9310, U-9340, and Zhanxin Resin's UVACURE 1534 and UVACURE 1562.

[0026] According to some preferred embodiments of the present invention, the polyurethane acrylate oligomer is at least one of Changxing Company's 6145-100, 6150-100, 6161-100, 6170-100, DR-U198 and DR-U381.

[0027] According to some preferred embodiments of the present invention, the polymerization inhibitor comprises tris(N-nitroso-N-phenylhydroxylamine) aluminum salt.

[0028] According to some preferred embodiments of the present invention, the polymerization inhibitor is at least one of Omnistab IN 510, Omnistab IN 515, Omnistab IN 516, Omnistab IN 518, Omnistab IN 520 and Omnistab IC from IGM Corporation.

[0029] According to some preferred embodiments of the present invention, the cationic photoinitiator is at least one of GR-IS051, GR-IS054, GR-SS058, and GR-SS061 from Hubei Gurun Technology Co., Ltd., and Uyracure 160, Uyracure 180, Uyracure 1600L, Uyracure 2500L, Uyracure 250, Uyracure 261, and Uyracure 290 from Shenzhen Youyang Co., Ltd.

[0030] According to some preferred embodiments of the present invention, the free radical photoinitiator is at least one of BASF's Irgacure 184, Darocur 1173, Irgacure TPO, Irgacure TPO-L, Irgacure 819 and Darocur BP.

[0031] According to some preferred embodiments of the present invention, the talc powder is at least one of 400 mesh, 600 mesh, 800 mesh, 1000 mesh, 1250 mesh and 3000 mesh from Monkey Saint Company.

[0032] According to some preferred embodiments of the present invention, the defoamer is at least one of BYK 055, BYK 141, and BYK 072 from BYK GmbH, Germany; TEGO Airex 920 and TEGO Airex 990 from Evonik Degussa; and KYOEISHA AC270 from Kyoeisha.

[0033] According to some preferred embodiments of the present invention, the leveling agent is at least one of BYK UV3575, BYK UV 3576, BYK 333, BYK358N from BYK GmbH, Germany, and TEGO Glide 100 and TEGO Flow425 from Evonik Degussa.

[0034] According to some preferred embodiments of the present invention, the wetting and dispersing agent is Evonik Degussa's TEGORad2011, TEGO Rad 2300, and TEGO Wet 270, and BYK's BYK 2009, BYK 378, and BYK 3535.

[0035] A second aspect of the present invention provides a method for preparing a triple-curing pine wood sealing UV coating, comprising: mixing and dispersing the raw materials according to a weight ratio.

[0036] According to some embodiments of the present invention, the dispersion rotation speed is 1300-1700 r / min, and the dispersion time is 15-25 min.

[0037] A third aspect of the present invention provides the application of triple-curing pine wood sealing UV coating in the surface coating of pine wood substrates.

[0038] According to some embodiments of the present invention, the coating method is selected from at least one of roller coating, brush coating, spray coating and curtain coating.

[0039] The triple-curing pine wood sealing UV coating obtained by this invention can solve the problems of paint film defects such as "oil seepage", blistering and delamination when pine wood is baked at 70℃, when used as the first coating on pine wood substrate.

[0040] A fourth aspect of the present invention provides a pine wood product comprising a pine wood substrate and a coating formed on the surface of the triple-cured pine wood sealing UV coating. Detailed Implementation

[0041] To enable those skilled in the art to more clearly understand the technical solutions described in this invention, the following embodiments are provided for illustration. It should be noted that the following embodiments do not constitute a limitation on the scope of protection claimed by this invention.

[0042] Unless otherwise specified, the raw materials, reagents or devices used in the following examples are available from conventional commercial sources or can be obtained by existing known methods.

[0043] Example 1

[0044] A triple-curing pine wood sealing UV coating 1 is prepared by the following steps:

[0045] By weight, the composition includes: 38.28 parts cationic UV resin U-9310, 10.0 parts polyurethane acrylate oligomer 6145-100, 10 parts reactive monomer SM631, 13 parts reactive monomer GR-OTX-1, 0.02 parts polymerization inhibitor Omnistab IN 510, 1.5 parts cationic photoinitiator GR-IS051, 1.0 part free radical photoinitiator Omnirad 1173, 0.125 parts catalyst AlCl3, 0.075 parts catalyst SbCl3, 25.0 parts 400-mesh talc, 0.1 parts defoamer BYK 055, 0.2 parts leveling agent BYKUV 3575, and 0.1 parts wetting agent TEGO Rad. In 2011, a triple-cured pine wood sealing UV coating was prepared by medium-high speed dispersion (1300-1700 rpm) for 15-25 minutes. The viscosity was measured to be 4600 cp using a Brookfield rotational viscometer at 25°C.

[0046] Triple-curing pine wood sealing UV coating 1 was roller-coated onto a pine substrate containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0047] Example 2

[0048] A triple-curing pine wood sealing UV coating 2 is prepared by the following steps:

[0049] By weight, 38.95 parts of cationic UV resin U-9210, 15.0 parts of polyurethane acrylate oligomer 6150-100, 10 parts of active monomer EM235, 13 parts of active monomer VM-3510, 0.05 parts of polymerization inhibitor Omnistab IN 515, 1.0 part of cationic photoinitiator GR-IS054, 0.5 parts of free radical photoinitiator Omnirad 184, 0.25 parts of catalyst AlCl-3, 20.0 parts of 800-mesh talc, 0.2 parts of defoamer BYK 141, 0.1 parts of leveling agent BYK UV 3576, and 0.2 parts of wetting agent TEGO Rad 2300 were dispersed at medium-high speed (1300-1700 rpm) for 20 min to prepare triple-curing pine wood sealing UV coating 2. The viscosity was measured to be 4300 cp at 25℃ using a Brookfield rotational viscometer.

[0050] Triple-curing pine wood sealing UV coating 2 was roller-coated onto a pine substrate containing knots, with a coating amount of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0051] Example 3

[0052] A triple-curing pine wood sealing UV coating 3 is prepared by the following steps:

[0053] By weight, the composition includes: 44.44 parts of cationic UV resin Omnilane OC2005, 20.0 parts of polyurethane acrylate oligomer 6161-100, 5.0 parts of active monomer EM242, 10 parts of active monomer GR-OTX-2, 0.06 parts of polymerization inhibitor OmnistabIN 516, 2.0 parts of cationic photoinitiator GR-SS058, 1.5 parts of free radical photoinitiator Omnirad TPO, 0.25 parts of catalyst AlCl3(C2H5)O, 0.125 parts of catalyst SbCl3, 15.0 parts of 1000-mesh talc, 0.1 parts of defoamer BYK 072, 0.3 parts of leveling agent BYK 333, and 0.1 parts of wetting agent TEGO. 270, medium-high speed dispersion (1300-1700 rpm) for 20 min yielded triple-cured pine wood sealing UV coating 3. The viscosity was measured at 25℃ using a Brookfield rotational viscometer and was 3950 cp.

[0054] Triple-curing pine wood sealing UV coating 3 was roller-coated onto a pine substrate containing knots, with a coating amount of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0055] Example 4

[0056] A triple-curing pine wood sealing UV coating 4 is prepared by the following steps:

[0057] By weight, the composition includes: 33.6 parts of cationic UV resin Omnilane OC3005, 10.5 parts of polyurethane acrylate oligomer 6170-100, 5.0 parts of reactive monomer SM623, 14.5 parts of reactive monomer VM-3530, 0.1 parts of polymerization inhibitor OmnistabIN 518, 3.0 parts of cationic photoinitiator GR-SS061, 1.0 part of free radical photoinitiator Omnirad MBF, 0.25 parts of catalyst AlCl3, 0.15 parts of catalyst BF3(C2H5)O, 30.0 parts of 1000-mesh talc, 0.3 parts of defoamer TEGOAirex920, 0.1 parts of leveling agent BYK 358N, and 0.3 parts of wetting agent BYK. In 2009, triple-cured pine wood sealing UV coating 4 was prepared by medium-high speed dispersion (1300-1700 rpm) for 20 min. The viscosity was measured to be 4750 cp by Brookfield rotational viscometer at 25℃.

[0058] Triple-curing pine wood sealing UV coating 4 was roller-coated onto a pine substrate containing knots, with a coating amount of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0059] Example 5

[0060] A triple-curing pine wood sealing UV coating 5 is prepared by the following steps:

[0061] By weight, the composition includes: 37.0 parts of cationic UV resin UVACURE 1534, 10.0 parts of polyurethane acrylate oligomer DR-198, 10.0 parts of reactive monomer EM221, 12.0 parts of reactive monomer GR-OTX-3, 0.5 parts of polymerization inhibitor Omnistab IN510, 1.5 parts of cationic photoinitiator Uyracure 160, 2.0 parts of free radical photoinitiator Omnirad TPO-L, 0.175 parts of catalyst AlCl3, 0.175 parts of catalyst AlBr3, 25.0 parts of 800-mesh talc, 0.1 parts of defoamer TEGOAirex 990, 0.1 parts of leveling agent TEGO Glide 100, and 0.4 parts of wetting agent BYK. 378, a triple-cured pine wood sealing UV coating was prepared by medium-high speed dispersion (1300-1700 rpm) for 20 min. The viscosity was measured to be 4350 cp using a Brookfield rotational viscometer at 25℃.

[0062] Triple-curing pine wood sealing UV coating 5 was roller-coated onto a pine substrate containing knots, with a coating amount of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0063] Example 6

[0064] A triple-curing pine wood sealing UV coating 6 is prepared by the following steps:

[0065] By weight, the composition includes: 38.35 parts of cationic UV resin UVACURE 1562, 8.0 parts of polyurethane acrylate oligomer DR-U381, 20.0 parts of reactive monomer SM631, 5.0 parts of reactive monomer VM-3520, 0.05 parts of polymerization inhibitor Omnistab IC, 1.5 parts of cationic photoinitiator Uyracure 180, 0.7 parts of free radical photoinitiator Omnirad 819, 0.15 parts of catalyst AlCl3, 0.05 parts of catalyst SbCl3, 25.0 parts of 1200-mesh talc, 0.2 parts of defoamer KYOEISHA 425, 0.2 parts of leveling agent TEGO Flow 425, and 0.2 parts of wetting agent BYK. 3535, medium-high speed dispersion (1300-1700 rpm) for 20 min yielded triple-cured pine wood sealing UV coating 6. The viscosity was measured at 25℃ using a Brookfield rotational viscometer and was 4100 cp.

[0066] Triple-curing pine wood sealing UV coating 6 was roller-coated onto a pine substrate containing knots, with a coating amount of 25 g / m². 2Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0067] Comparative Example 1

[0068] A UV coating 7, which differs from the comparative example and Example 1 in that it is a conventional UV coating without the addition of cationic UV resin, vinyl ether monomers, oxetane monomers, cationic photoinitiators, catalysts, and polymerization inhibitors, is prepared by the following steps:

[0069] UV coating 7 was prepared by dispersing at medium to high speed (1300-1700 rpm) for 15-25 minutes using 48.28 parts by weight of polyurethane acrylate oligomer 6145-100, 23.0 parts by weight of active monomer SM631, 2.5 parts by weight of free radical photoinitiator Omnirad 1173, 25.0 parts by weight of 400 mesh talc, 0.1 parts by weight of defoamer BYK 055, 0.2 parts by weight of leveling agent BYK UV 3575, and 0.1 parts by weight of wetting agent TEGO Rad 2011. The viscosity was 5500 cp when measured at 25°C using a Brookfield rotational viscometer.

[0070] UV coating 7 was roller-coated onto a pine substrate containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0071] Comparative Example 2

[0072] A UV coating 8, which differs from the comparative example and Example 1 in that it does not contain cationic UV resin, vinyl ether monomers, oxetane monomers, or polymerization inhibitors, is prepared by the following steps:

[0073] By weight, 48.28 parts of polyurethane acrylate oligomer 6145-100, 23.0 parts of active monomer SM631, 1.5 parts of cationic photoinitiator GR-IS051, 1.0 parts of free radical photoinitiator Omnirad 1173, 0.125 parts of catalyst AlCl-3, 0.075 parts of catalyst SbCl3, 25.0 parts of 400-mesh talc, 0.1 parts of defoamer BYK 055, 0.2 parts of leveling agent BYK UV 3575, and 0.1 parts of wetting agent TEGO Rad 2011 were dispersed at medium to high speed (1300-1700 rpm) for 15-25 minutes to obtain UV coating 8. The viscosity was measured to be 6200 cp at 25℃ using a Brookfield rotational viscometer.

[0074] UV coating 8 was roller-coated onto a pine substrate containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0075] Comparative Example 3

[0076] A UV coating 9, which differs from the comparative example and Example 1 in that it does not contain a cationic photoinitiator, is prepared by the following steps:

[0077] By weight, 38.28 parts of cationic UV resin U-9310, 10.0 parts of polyurethane acrylate oligomer 6145-100, 10 parts of active monomer SM631, 13 parts of active monomer GR-OTX-1, 0.02 parts of polymerization inhibitor Omnistab IN 510, 2.5 parts of free radical photoinitiator Omnirad 1173, 0.125 parts of catalyst AlCl3, 0.075 parts of catalyst SbCl3, 25.0 parts of 400-mesh talc, 0.1 parts of defoamer BYK 055, 0.2 parts of leveling agent BYK UV 3575, and 0.1 parts of wetting agent TEGO Rad2011 were dispersed at medium to high speed (1300-1700 rpm) for 15-25 minutes to obtain UV coating 9. The viscosity was measured to be 4450 cp using a Brookfield rotational viscometer at 25°C. UV coating 9 was roller-coated onto a pine substrate containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0078] Comparative Example 4

[0079] A UV coating 10, which differs from the comparative example and Example 1 in that no catalyst is added, i.e., the ratio of the sum of the weight parts of the cationic UV resin and the oxetane monomer to the weight parts of the catalyst is higher than 300, is prepared by the following steps:

[0080] By weight, 38.28 parts of cationic UV resin U-9310, 10.0 parts of polyurethane acrylate oligomer 6145-100, 10 parts of active monomer SM631, 13 parts of active monomer GR-OTX-1, 0.02 parts of polymerization inhibitor Omnistab IN 510, 1.5 parts of cationic photoinitiator GR-IS051, 1.0 part of free radical photoinitiator Omnirad 1173, 25.0 parts of 400-mesh talc, 0.1 parts of defoamer BYK 055, 0.2 parts of leveling agent BYK UV 3575, and 0.1 parts of wetting agent TEGO Rad 2011 were dispersed at medium to high speed (1300-1700 rpm) for 15-25 minutes to obtain UV coating 10. The viscosity was measured to be 4500 cp using a Brookfield rotational viscometer at 25°C.

[0081] UV coating 10 was roller-coated onto a pine substrate containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0082] Comparative Example 5

[0083] A UV coating 11, the difference between this comparative example and Example 1, is that the ratio of the sum of the weight parts of the cationic UV resin and the oxetane monomer to the weight parts of the catalyst is higher than 300, and it is prepared by the following steps:

[0084] By weight, the composition includes: 38.28 parts cationic UV resin U-9310, 10.0 parts polyurethane acrylate oligomer 6145-100, 10 parts reactive monomer SM631, 13 parts reactive monomer GR-OTX-1, 0.02 parts polymerization inhibitor Omnistab IN 510, 1.5 parts cationic photoinitiator GR-IS051, 1.0 part free radical photoinitiator Omnirad 1173, 0.0625 parts catalyst AlCl3, 0.0375 parts catalyst SbCl3, 25.0 parts 400-mesh talc, 0.1 parts defoamer BYK 055, 0.2 parts leveling agent BYK UV 3575, and 0.1 parts wetting agent TEGO Rad. In 2011, UV coating 10 was prepared by medium-high speed dispersion (1300-1700 rpm) for 15-25 minutes. The viscosity was measured to be 4650 cp using a Brookfield rotational viscometer at 25°C.

[0085] UV coating 11 was roller-coated onto a pine substrate containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm².2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0086] Comparative Example 6

[0087] A UV coating 12, the difference between this comparative example and Example 1, is that an excessive amount of catalyst is added, and the ratio of the sum of the weight parts of the cationic UV resin and the oxetine monomer to the weight parts of the catalyst is 85.5. It is prepared by the following steps:

[0088] By weight, the composition includes: 38.28 parts cationic UV resin U-9310, 10.0 parts polyurethane acrylate oligomer 6145-100, 10 parts reactive monomer SM631, 13 parts reactive monomer GR-OTX-1, 0.02 parts polymerization inhibitor Omnistab IN 510, 1.5 parts cationic photoinitiator GR-IS051, 1.0 part free radical photoinitiator Omnirad 1173, 0.375 parts catalyst AlCl3, 0.225 parts catalyst SbCl3, 25.0 parts 400-mesh talc powder, 0.1 parts defoamer BYK 055, 0.2 parts leveling agent BYKUV 3575, and 0.1 parts wetting agent TEGO Rad. In 2011, a triple-cured pine wood sealing UV coating was prepared by medium-high speed dispersion (1300-1700 rpm) for 15-25 minutes. The viscosity was measured to be 4600 cp using a Brookfield rotational viscometer at 25°C.

[0089] Triple-curing pine wood sealing UV coating 12 was roller-coated onto a pine substrate containing knots, with a coating amount of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0090] Comparative Example 7

[0091] A UV coating 13, which differs from the comparative example and Example 1 in that no polymerization inhibitor is added, is prepared by the following steps:

[0092] By weight, 38.28 parts of cationic UV resin U-9310, 10.0 parts of polyurethane acrylate oligomer 6145-100, 10 parts of active monomer SM631, 13 parts of active monomer GR-OTX-1, 1.5 parts of cationic photoinitiator GR-IS051, 1.0 part of free radical photoinitiator Omnirad 1173, 0.125 parts of catalyst AlCl3, 0.075 parts of catalyst SbCl3, 25.0 parts of 400-mesh talc, 0.1 parts of defoamer BYK 055, 0.2 parts of leveling agent BYK UV 3575, and 0.1 parts of wetting agent TEGO Rad 2011 were dispersed at medium to high speed (1300-1700 rpm) for 15-25 minutes to obtain UV coating 11. The viscosity measured at 25°C using a Brookfield rotational viscometer was 4550 cp. UV coating 13 was roller-coated onto a pine substrate containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process once, and the performance is shown in Table 1.

[0093] Test Example 1

[0094] The UV coatings prepared in the examples and comparative examples were rolled onto pine wood substrates containing knots, with a coating weight of 25 g / m². 2 Turn on the mercury lamp in the UV curing machine and adjust the UVA energy to 100 mJ / cm². 2 After curing, the same amount of coating and curing energy were used to repeat the roller coating process. After baking at 70℃ for 2 hours, the properties are shown in Table 1.

[0095] Coating appearance: visual inspection;

[0096] Adhesion: GB / T9286-2021.

[0097] Table 1. Sealing performance of UV coatings for pine wood sealing

[0098]

[0099] As can be seen from the table above, compared with Example 1, the paint films of Comparative Example 1 (without cationic UV resin, cationic photoinitiator, catalyst, and polymerization inhibitor) and Comparative Example 3 (without cationic photoinitiator) exhibited oil seepage, blistering, whitening, and delamination after baking at 70°C for 2 hours, and their adhesion was very poor, significantly inferior to Example 1; Comparative Example 2 (without cationic UV resin, vinyl ether monomers, and oxetane monomers) also exhibited oil seepage, whitening, and delamination, and its adhesion was also poor, significantly inferior to Example 1; because the catalyst can catalyze the cationic UV... The V resin, vinyl ether monomers, and oxetane monomers underwent a polymerization reaction. The paint film of Comparative Example 4, without the addition of a catalyst, exhibited oil seepage and blistering after baking at 70°C for 2 hours, and its adhesion was poor. The paint film of Comparative Example 5, with insufficient catalyst, also exhibited oil seepage after baking at 70°C for 2 hours, and its adhesion was better than that of Comparative Example 4 but not as good as that of Example 1. The paint films of Comparative Example 6, with an excessively high catalyst content, and Comparative Example 7, without the addition of a polymerization inhibitor, showed no abnormalities in appearance after baking at 70°C for 2 hours, but their storage stability was not as good as that of Example 1.

[0100] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A triple-curing UV coating for sealing pine wood, characterized in that, The raw materials include: cationic UV resin, polyurethane acrylate oligomer, active monomer, polymerization inhibitor, cationic photoinitiator, free radical photoinitiator, and catalyst; The active monomers include at least two of the following: acrylate monomers containing double bonds, vinyl ether monomers, and oxetane monomers; Polymerization inhibitors include tris(N-nitroso-N-phenylhydroxylamine) aluminum salt; The catalyst includes at least one of AlCl3, SbCl3, AlBr3, AlCl3(C2H5)2O and BF3(C2H5)2O; By weight, the triple-curing pine wood sealing UV coating comprises the following raw materials: 30.0-45.0 parts of cationic UV resin, 5.0-20.0 parts of polyurethane acrylate oligomer, 15.0-25.0 parts of active monomer, 0.01-0.5 parts of polymerization inhibitor, 1.0-3.0 parts of cationic photoinitiator, 0.5-2.0 parts of free radical photoinitiator, and 0.25-0.4 parts of catalyst.

2. The triple-curing pine wood sealing UV coating according to claim 1, characterized in that, The triple-curing pine wood sealing UV coating also includes at least one of the following raw materials: talc, defoamer, leveling agent and wetting agent.

3. The triple-curing pine wood sealing UV coating according to claim 2, characterized in that, The triple-curing pine wood sealing UV coating also includes the following raw materials: talc, defoamer, leveling agent and wetting agent. By weight, the triple-curing pine wood sealing UV coating includes the following raw materials: 30.0~45.0 parts of cationic UV resin, 15.0~30.0 parts of talc, 0.1~0.3 parts of defoamer, 0.1~0.3 parts of leveling agent and 0.1~0.4 parts of wetting agent.

4. The triple-curing pine wood sealing UV coating according to claim 1, characterized in that, The polyurethane acrylate oligomer is an aliphatic polyurethane acrylate oligomer with an acid value <5 and a hexafunctionality not exceeding 5.

5. A method for preparing a triple-curing pine wood sealing UV coating as described in any one of claims 1 to 4, characterized in that, include: The components are mixed and dispersed to obtain the triple-cured pine wood sealing UV coating.

6. The preparation method according to claim 5, characterized in that, The dispersion speed is 1300~1700 r / min, and the dispersion time is 15~25 min.

7. The application of the triple-curing pine wood sealing UV coating according to any one of claims 1 to 4 in the surface coating of pine wood substrates.

8. A pine wood product, characterized in that, The pine wood products include a pine wood substrate and a coating formed on the surface of the pine wood substrate by the triple-curing pine wood sealing UV coating as described in any one of claims 1 to 4.

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