A surface veneering process for decorative wood panels

Abstract

The present application relates to the technical field of decorative wood board, in particular to a surface veneering process of decorative wood board, which comprises a kind of adhesive for the surface veneering of decorative wood board, and the adhesive comprises the following components: by mass fraction: modified attapulgite 5-12 parts, urea-formaldehyde resin 95-100 parts, white latex 13-18 parts, curing agent 0.5-1 part; the modified attapulgite comprises the following components: attapulgite powder, p-phenylene diisocyanate and cyclohexane-1,2-dicarboxylic anhydride; the white latex comprises the following components: water-resistant polyvinyl acetate oligomer, vinyl acetate, modified porcelain powder, sodium thiosulfate, sodium hydroxide, urea and water. Finally, the adhesive is coated on one side of the substrate, and then the panel is attached to the side, and after pressing and trimming, the decorative wood board is obtained.

Description

Technical Field

[0001] This invention relates to the field of decorative wood panel technology, specifically to a surface veneer process for decorative wood panels. Background Technology

[0002] Decorative veneer plywood, also known as decorative veneer plywood, is a type of board made by precisely slicing solid wood into thin veneers, using plywood as the base material, and then bonding them together. It serves both decorative and protective purposes, and can be used in furniture and various wood products. In daily life, it is commonly used on wood flooring. However, the bonding strength between the veneer and the base material in existing wood flooring is relatively poor, which is not conducive to long-term use. Furthermore, most adhesives used in existing decorative wood flooring have poor weather resistance; excessively high or low temperatures, or excessively high or low pH levels, will significantly affect their bonding performance.

[0003] In summary, this invention focuses on an adhesive with high bonding performance and certain weather resistance, which can broaden the service life and application of decorative wood panels, and is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a surface veneer process for decorative wood panels to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] An adhesive for surface veneer of decorative wood panels, the adhesive comprising the following components by weight: 5-12 parts modified attapulgite, 95-100 parts urea-formaldehyde resin, 13-18 parts white glue, and 0.5-1 part curing agent.

[0007] Furthermore, the modified attapulgite comprises the following components: by mass parts: 8-14 parts of attapulgite powder, 7-9 parts of terephthalic diisocyanate, and 7-8 parts of cyclohexane-1,2-dicarboxylic anhydride.

[0008] Furthermore, the white latex comprises the following components by mass: 15-20 parts of oligomeric water-resistant polyvinyl acetate, 2-5 parts of vinyl acetate, 2-4 parts of modified ceramic powder, 3-6 parts of sodium thiosulfate, 1-2 parts of sodium hydroxide, 0.1-0.5 parts of urea, and 6-12 parts of water.

[0009] Furthermore, the preparation steps of the adhesive are as follows:

[0010] S1: Attapulgite was grafted with terephthalic diisocyanate and cyclohexane-1,2-dicarboxylic anhydride to obtain modified attapulgite.

[0011] S2: Mix oligomeric water-resistant polyvinyl acetate, vinyl acetate, modified ceramic powder, sodium thiosulfate, sodium hydroxide, urea and water evenly to obtain white latex;

[0012] S3: Mix the modified attapulgite, urea-formaldehyde resin, white glue and curing agent evenly to obtain the adhesive.

[0013] Furthermore, the modified attapulgite is prepared as follows: attapulgite powder is added to an N-methylpyrrolidone solution and ultrasonically dispersed for 30–60 min to form a suspension with a concentration of 0.20–0.35 g / mL; under nitrogen protection, the suspension is heated to 50–70 °C, and terephthalic diisocyanate is added to it, and the mixture is stirred and refluxed at 100–200 r / min for 6–12 h; the temperature is then raised to 90–110 °C, cyclohexane-1,2-dicarboxylic anhydride is added, and the mixture is stirred and refluxed at 100–200 r / min for 4–8 h to complete the reaction; after the reactants are cooled to room temperature, they are filtered, washed, and dried to obtain the modified attapulgite.

[0014] Furthermore, the preparation method of the oligomeric water-resistant polyvinyl acetate is as follows:

[0015] (1) Add polyvinyl alcohol to deionized water, heat to 95-100℃, and stir continuously at 200-400r / min until the polyvinyl alcohol is completely dissolved. After cooling to room temperature, add an appropriate amount of sodium acetate to adjust the pH value to 4.8-5.1 to obtain a polyvinyl alcohol solution.

[0016] (2) Add azobisisobutyronitrile to the vinyl acetate monomer, stir thoroughly to disperse it in the monomer, and divide the monomer into two parts with a volume ratio of 1:2.

[0017] (3) Heat the polyvinyl alcohol solution to 65-75°C, add the smaller volume of monomer to the polyvinyl alcohol solution, and stir at 100-200 r / min for 20-40 min; continue stirring, and add the remaining monomer to the polyvinyl alcohol solution at a dropping rate of 1-2 mL / min. After the addition is complete, keep warm for 1-2 h, and let it cool to room temperature. Pass it through a 50-100 mesh sieve, wash it with anhydrous ethanol, and dry it at 60-70°C to obtain oligomeric water-resistant polyvinyl acetate.

[0018] Furthermore, the mass ratio of the polyvinyl alcohol and vinyl acetate monomers is 1:(2-6).

[0019] Furthermore, the amount of azobisisobutyronitrile added is 0.6% to 1% of the mass of vinyl acetate monomer.

[0020] Furthermore, the modification process of the modified ceramic powder is as follows: ceramic powder, γ-methacryloxypropyltrimethoxysilane and anhydrous ethanol are mixed and stirred at a speed of 400-800 r / min for 10-20 min, and the mixture is dried at 50-60℃ until the anhydrous ethanol is completely evaporated to obtain modified ceramic powder.

[0021] Furthermore, the mass ratio of the ceramic powder, γ-methacryloyloxypropyltrimethoxysilane, and anhydrous ethanol is 50:3:1.

[0022] Furthermore, the adhesive is applied to one side of the substrate, and then the panel is attached to that side. After pressing and trimming, a decorative wood panel is obtained.

[0023] Furthermore, the processing method of the decorative wood panel is as follows: one side of both the substrate and the panel is polished to a surface roughness of 24-48 μm, and dried to a moisture content of 7-10%; then an adhesive is applied to the polished surface of the substrate, with a coating amount of 180-230 g / m². 2 The polished surface of the panel is attached to the polished surface of the substrate coated with adhesive; finally, after pressing under a pressure of 0.1-0.4 MPa for 1-2 hours, the temperature is raised to 105-110℃ and rolled under a pressure of 3-5 MPa for 3-5 hours to obtain the decorative wood panel.

[0024] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The present invention improves the bonding performance and weather resistance of urea-formaldehyde resin by grafting and modifying attapulgite, introducing imide groups, and then mixing and modifying it with urea-formaldehyde resin; in addition, a white latex is formulated to improve the fluidity of the resin and avoid the resin becoming too thick and difficult to coat due to the addition of grafting and fillers, while synergistically strengthening the bonding strength of the adhesive with the imide groups, ultimately obtaining an adhesive with high bonding performance and weather resistance.

[0025] (1) In the preparation of the above-mentioned modified attapulgite, isocyanate groups are grafted onto the surface of attapulgite, and then cyclohexane-1,2-dicarboxylic anhydride is added to react with the groups to generate polyimide. On the one hand, attapulgite itself can act as an additive for the adhesive, increasing its viscosity and making the adhesive more easily adhered to the coating surface. At the same time, it can also provide some protection to the adhesive, making it less susceptible to the effects of light, heat, and oxygen. On the other hand, the imide group has high polarity, which can increase adhesion and improve the adhesive's resistance to high and low temperatures, acid and alkali, etc. The synergistic effect of attapulgite and imide groups improves the adhesion and weather resistance of the adhesive.

[0026] (2) The above-mentioned white glue contains oligomeric water-resistant polyvinyl acetate, which can appropriately improve the fluidity of the resin and avoid the resin becoming too thick due to grafting and the addition of fillers, which is not conducive to coating and gluing. It can also enhance the water resistance of the adhesive and further improve its weather resistance. At the same time, ceramic powder is added as a filler to enhance the adhesion. It is modified with γ-methacryloxypropyltrimethoxysilane. Since the silane coupling agent can improve the adhesive's resistance to damp heat aging, the adhesive performance of the adhesive is improved, and the weather resistance is also improved. Sodium thiosulfate in the white glue has certain micro-corrosive and antioxidant properties, so it can better penetrate the adhesive into the substrate, so that the substrate and the panel are effectively bonded together, which can avoid the glue evaporation and improve the bonding effect. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In the following embodiments, the substrate is birch plywood with dimensions of 2400mm (length) × 1200mm (width) × 8mm (thickness) (Linyi Lanshan District Beijita Wood Industry Board Factory); the veneer is ash wood with dimensions of 2500mm (length) × 1250mm (width) × 1mm (thickness) (Foshan Lineng Building Materials Co., Ltd.); the urea-formaldehyde resin has a purity of 60%, item number: T25354 (Shanghai Yuanye Biotechnology Co., Ltd.); the attapulgite powder has a purity of 98.5%, CAS number: 12174-11-7, and the powder... Appearance: 300-400 mesh (Guangzhou Yifeng Chemical Technology Co., Ltd.); N-methylpyrrolidone purity 99%, CAS No.: 872-50-4 (Hebei Mojin Biotechnology Co., Ltd.); terephthalic diisocyanate purity 99%, CAS No.: 104-49-4 (Hubei Wande Chemical Co., Ltd.); cyclohexane-1,2-dicarboxylic anhydride purity 98%, CAS No.: 13149-00-3 (Shanghai Yiji Industrial Co., Ltd.); polyvinyl alcohol purity 99%, CAS No.: 9002-89- 5 (Shandong Meichang New Material Technology Co., Ltd.); Sodium acetate purity 99% (Hebei Crowell Biotechnology Co., Ltd.); Azobisisobutyronitrile purity 99% (Hangzhou Zerui Chemical Co., Ltd.); Vinyl acetate monomer purity 100% (Zhangjiagang Free Trade Zone Zhaoguang Chemical Technology Co., Ltd.); Polyvinyl acetate purity 99.9%, average molecular weight 50,000 (Hebei Senfeng New Material Technology Co., Ltd.); Silicon nitride purity 99.8% (Xiamen Jingcai Biotechnology Co., Ltd.); γ-methacryloyloxy The purity of propyltrimethoxysilane is 99.5% (Hubei Jusheng Technology Co., Ltd.); the purity of anhydrous ethanol is 99% (Henan Tianfu Chemical Co., Ltd.); the purity of sodium chloride is 99% (Hebei Mojin Biotechnology Co., Ltd.); the purity of vinyl acetate is 99% (Henan Tianfu Chemical Co., Ltd.); the purity of sodium thiosulfate is 99% (Hebei Zhentian Food Additives Co., Ltd.); the purity of sodium hydroxide is 99% (Henan Tianfu Chemical Co., Ltd.); and the purity of urea is 99% (Hebei Zhentian Food Additives Co., Ltd.).

[0029] Example 1: An adhesive for surface veneer of decorative wood panels:

[0030] S1: The preparation method of modified attapulgite is as follows: 10 parts of attapulgite powder are added to N-methylpyrrolidone solution and ultrasonically dispersed for 60 min to form a suspension with a concentration of 0.30 g / mL; under nitrogen protection, the suspension is heated to 60℃ and 8 parts of terephthalic diisocyanate are added to it, and the mixture is stirred and refluxed at 200 r / min for 8 h; then the temperature is raised to 95℃ and 7 parts of cyclohexane-1,2-dicarboxylic anhydride are added, and the mixture is stirred and refluxed at 200 r / min for 8 h to end the reaction; after the reactants are cooled to room temperature, they are filtered, washed and dried to obtain modified attapulgite.

[0031] S2: The preparation method of oligomeric water-resistant polyvinyl acetate is as follows:

[0032] (1) Add 10 parts of polyvinyl alcohol to deionized water, heat to 98°C, and stir continuously at 300 r / min until the polyvinyl alcohol is completely dissolved. After cooling to room temperature, add an appropriate amount of sodium acetate to adjust the pH value to 5.0 to obtain a polyvinyl alcohol solution.

[0033] (2) Add 0.35 parts of azobisisobutyronitrile to 35 parts of vinyl acetate monomer, stir thoroughly to disperse it in the monomer, and divide the monomer into two parts with a volume ratio of 1:2.

[0034] (3) Heat the polyvinyl alcohol solution to 70°C, add the smaller volume of monomer to the polyvinyl alcohol solution, and stir at 100 r / min for 30 min; continue stirring, and add the remaining monomer to the polyvinyl alcohol solution at a dropping rate of 1 mL / min. After the addition is complete, keep warm for 2 h, let it cool to room temperature, pass it through a 100-mesh sieve, wash it with anhydrous ethanol, and dry it at 60°C to obtain oligomeric water-resistant polyvinyl acetate.

[0035] The modification process of the modified ceramic powder is as follows: 5 parts of silicon nitride ceramic powder, 0.3 parts of γ-methacryloyloxypropyltrimethoxysilane and 0.1 parts of anhydrous ethanol are mixed and stirred at 600 r / min for 20 min. The mixture is then dried at 60℃ until the anhydrous ethanol is completely evaporated to obtain the modified ceramic powder.

[0036] S3: (1) Mix 16 parts of low-polymer water-resistant polyvinyl acetate, 4 parts of vinyl acetate, 3 parts of modified ceramic powder, 3 parts of sodium thiosulfate, 1 part of sodium hydroxide, 0.3 parts of urea, and 10 parts of water evenly to obtain white latex.

[0037] (2) Mix 10 parts of modified attapulgite, 95 parts of urea-formaldehyde resin, 15 parts of white latex and 0.6 parts of sodium chloride evenly to obtain an adhesive.

[0038] S4: The processing method for decorative wood panels is as follows: polish one side of both the birch plywood substrate and the ash wood veneer to a surface roughness of 24μm, and dry them to a moisture content of 9%; then apply adhesive to the polished surface of the substrate at a coating amount of 200g / m². 2 The polished surface of the panel is attached to the polished surface of the substrate coated with adhesive; finally, after pressing at 0.2 MPa pressure for 1 hour, the temperature is raised to 105℃ and rolled at 4 MPa pressure for 5 hours to obtain the decorative wood panel.

[0039] Example 2: An adhesive for surface veneer of decorative wood panels:

[0040] S1: The preparation method of modified attapulgite is as follows: 8 parts of attapulgite powder are added to N-methylpyrrolidone solution and ultrasonically dispersed for 30 min to form a suspension with a concentration of 0.20 g / mL; under nitrogen protection, the suspension is heated to 60℃ and 7 parts of terephthalic diisocyanate are added to it, and the mixture is stirred and refluxed at 100 r / min for 6 h; then the temperature is raised to 90℃ and 7 parts of cyclohexane-1,2-dicarboxylic anhydride are added, and the mixture is stirred and refluxed at 100 r / min for 4 h to end the reaction; after the reactants are cooled to room temperature, they are filtered, washed and dried to obtain modified attapulgite.

[0041] S2: The preparation method of oligomeric water-resistant polyvinyl acetate is as follows:

[0042] (1) Add 10 parts of polyvinyl alcohol to deionized water, heat to 95°C, and stir continuously at 200 r / min until the polyvinyl alcohol is completely dissolved. After cooling to room temperature, add an appropriate amount of sodium acetate to adjust the pH value to 4.8 to obtain a polyvinyl alcohol solution.

[0043] (2) Add 0.12 parts of azobisisobutyronitrile to 20 parts of vinyl acetate monomer, stir thoroughly to disperse it in the monomer, and divide the monomer into two parts with a volume ratio of 1:2.

[0044] (3) Heat the polyvinyl alcohol solution to 65°C, add the smaller volume of monomer to the polyvinyl alcohol solution, and stir at 100 r / min for 20 min; continue stirring, and add the remaining monomer to the polyvinyl alcohol solution at a dropping rate of 2 mL / min. After the addition is complete, keep warm for 1 h, let it cool to room temperature, pass it through a 50-mesh sieve, wash it with anhydrous ethanol, and dry it at 60°C to obtain oligomeric water-resistant polyvinyl acetate.

[0045] The modification process of the modified ceramic powder is as follows: 5 parts of silicon nitride ceramic powder, 0.3 parts of γ-methacryloyloxypropyltrimethoxysilane and 0.1 parts of anhydrous ethanol are mixed and stirred at 600 r / min for 20 min. The mixture is then dried at 60℃ until the anhydrous ethanol is completely evaporated to obtain the modified ceramic powder.

[0046] S3: (1) Mix 15 parts of low-polymer water-resistant polyvinyl acetate, 3 parts of vinyl acetate, 2 parts of modified ceramic powder, 3 parts of sodium thiosulfate, 1 part of sodium hydroxide, 0.3 parts of urea, and 10 parts of water evenly to obtain white latex.

[0047] (2) Mix 10 parts of modified attapulgite, 95 parts of urea-formaldehyde resin, 15 parts of white latex and 0.6 parts of sodium chloride evenly to obtain an adhesive.

[0048] S4: The processing method for decorative wood panels is as follows: polish one side of both the birch plywood substrate and the ash wood veneer to a surface roughness of 48μm, and dry them to a moisture content of 7%; then apply adhesive to the polished surface of the substrate at a coating amount of 180g / m². 2 The polished surface of the panel is attached to the polished surface of the substrate coated with adhesive; finally, after pressing at 0.1 MPa for 1 hour, the temperature is raised to 105℃ and rolled at 3 MPa for 3 hours to obtain the decorative wood panel.

[0049] Example 3: An adhesive for surface veneer of decorative wood panels:

[0050] S1: The preparation method of modified attapulgite is as follows: 14 parts of attapulgite powder are added to N-methylpyrrolidone solution and ultrasonically dispersed for 60 min to form a suspension with a concentration of 0.35 g / mL; under nitrogen protection, the suspension is heated to 70℃ and 9 parts of terephthalic diisocyanate are added to it, and the mixture is stirred and refluxed at 200 r / min for 12 h; then the temperature is raised to 110℃ and 8 parts of cyclohexane-1,2-dicarboxylic anhydride are added, and the mixture is stirred and refluxed at 200 r / min for 8 h to end the reaction; after the reactants are cooled to room temperature, they are filtered, washed and dried to obtain modified attapulgite.

[0051] S2: The preparation method of oligomeric water-resistant polyvinyl acetate is as follows:

[0052] (1) Add 10 parts of polyvinyl alcohol to deionized water, heat to 110°C, and stir continuously at 400 r / min until the polyvinyl alcohol is completely dissolved. After cooling to room temperature, add an appropriate amount of sodium acetate to adjust the pH value to 5.1 to obtain a polyvinyl alcohol solution.

[0053] (2) Add 0.6 parts of azobisisobutyronitrile to 60 parts of vinyl acetate monomer, stir thoroughly to disperse it in the monomer, and divide the monomer into two parts with a volume ratio of 1:2.

[0054] (3) Heat the polyvinyl alcohol solution to 65°C, add the smaller volume of monomer to the polyvinyl alcohol solution, and stir at 200 r / min for 40 min; continue stirring, and add the remaining monomer to the polyvinyl alcohol solution at a dropping rate of 2 mL / min. After the addition is complete, keep warm for 2 h, let it cool to room temperature, pass it through a 100-mesh sieve, wash it with anhydrous ethanol, and dry it at 60°C to obtain oligomeric water-resistant polyvinyl acetate.

[0055] The modification process of the modified ceramic powder is as follows: 5 parts of silicon nitride ceramic powder, 0.3 parts of γ-methacryloyloxypropyltrimethoxysilane and 0.1 parts of anhydrous ethanol are mixed and stirred at 600 r / min for 20 min. The mixture is then dried at 60℃ until the anhydrous ethanol is completely evaporated to obtain the modified ceramic powder.

[0056] S3: (1) Mix 20 parts of low-polymer water-resistant polyvinyl acetate, 3 parts of vinyl acetate, 4 parts of modified ceramic powder, 6 parts of sodium thiosulfate, 1 part of sodium hydroxide, 0.3 parts of urea, and 10 parts of water evenly to obtain white latex.

[0057] (2) Mix 10 parts of modified attapulgite, 95 parts of urea-formaldehyde resin, 15 parts of white latex and 0.6 parts of sodium chloride evenly to obtain an adhesive.

[0058] S4: The processing method for decorative wood panels is as follows: polish one side of both the birch plywood substrate and the ash wood veneer to a surface roughness of 24μm, and dry them to a moisture content of 8%; then apply adhesive to the polished surface of the substrate at a coating amount of 230g / m². 2 The polished surface of the panel is attached to the polished surface of the substrate coated with adhesive; finally, after pressing at 0.4 MPa for 2 hours, the temperature is raised to 105℃ and rolled at 5 MPa for 5 hours to obtain the decorative wood panel.

[0059] Comparative Example 1: 5 parts of modified attapulgite, 95 parts of urea-formaldehyde resin, 13 parts of white latex and 0.6 parts of sodium chloride were mixed evenly to obtain an adhesive, and the other steps were the same as in Example 1.

[0060] Comparative Example 2: Without modifying the attapulgite, 10 parts of attapulgite, 95 parts of urea-formaldehyde resin, 15 parts of white latex and 0.6 parts of sodium chloride were mixed evenly to obtain an adhesive, and the rest was the same as in Example 1.

[0061] Comparative Example 3: Instead of preparing oligomeric water-resistant polyvinyl acetate, polyethyl acetate with an average molecular weight of 50,000 was used; 16 parts of polyvinyl acetate, 4 parts of vinyl acetate, 3 parts of modified ceramic powder, 3 parts of sodium thiosulfate, 1 part of sodium hydroxide, 0.3 parts of urea, and 10 parts of water were mixed evenly to obtain white latex, and the rest was the same as in Example 1.

[0062] Comparative Example 4: White latex without the addition of modified ceramic powder, 16 parts of oligomeric water-resistant polyvinyl acetate, 4 parts of vinyl acetate, 3 parts of sodium thiosulfate, 1 part of sodium hydroxide, 0.3 parts of urea, and 10 parts of water were mixed evenly to obtain white latex. Other aspects were the same as in Example 1.

[0063] Comparative Example 5: White glue without sodium thiosulfate was prepared by mixing 16 parts of oligomeric water-resistant polyvinyl acetate, 4 parts of vinyl acetate, 1 part of sodium hydroxide, 0.3 parts of urea, and 10 parts of water evenly to obtain white glue. Other aspects were the same as in Example 1.

[0064] Performance Testing: The decorative wood panels obtained in Examples 1-3 and Comparative Examples 1-5 were placed for 24 hours. Then, according to GB / T15104-2021, the surface bonding strength and surface resistance to thermal cycling were tested (test conditions: the decorative wood panels were treated in an 80℃ drying oven for 120 minutes, then treated at -20℃ for 120 minutes, repeated four times, and finally placed at room temperature for 24 hours to observe for surface defects or peeling). Their bonding ability and weather resistance were also tested. Details are shown in the table below:

[0065]

[0066] As shown in the table above, Example 1 is the optimal solution. In this invention, by introducing imide groups onto attapulgite and appropriately increasing the amount of silane coupling agent, the three synergistically improved the bonding performance and weather resistance. Furthermore, an oligomeric water-resistant polyvinyl acetate was prepared to adjust the consistency of the adhesive, making it easier to apply and penetrate the substrate, and less prone to peeling. Comparing Examples 1 and 2, it can be seen that the modified attapulgite has insufficient adsorbent and white glue content, which has a certain impact on the bonding strength between the substrate and the panel, but the decorative wood panel still exhibits good weather resistance. Comparing Examples 2 and 3, it can be seen that the imide groups play an important role in improving the bonding performance. Comparative Example 3 shows that the adhesive consistency is too high, which is not conducive to penetration and significantly affects the bonding performance. Finally, Examples 4 and 5 show that ceramic powder and sodium thiosulfate can promote bonding and enhance adhesion.

[0067] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a surface veneer for decorative wood panels, characterized in that: The preparation method is as follows: one side of both the substrate and the panel is polished to a surface roughness of 24-48 μm and dried to a moisture content of 7-10%; then an adhesive is applied to the polished surface of the substrate at a coating amount of 180-230 g / m². 2 The polished surface of the panel is attached to the polished surface of the substrate coated with adhesive; finally, after pressing under a pressure of 0.1-0.4 MPa for 1-2 hours, the temperature is raised to 105-110℃ and rolled under a pressure of 3-5 MPa for 3-5 hours to obtain the decorative wood panel. The adhesive comprises the following components by mass: 5-12 parts modified attapulgite, 95-100 parts urea-formaldehyde resin, 13-18 parts white glue, and 0.5-1 part curing agent. White glue comprises the following components by mass: 15-20 parts of oligomeric water-resistant polyvinyl acetate, 2-5 parts of vinyl acetate, 2-4 parts of modified ceramic powder, 3-6 parts of sodium thiosulfate, 1-2 parts of sodium hydroxide, 0.1-0.5 parts of urea, and 6-12 parts of water. The modified attapulgite is prepared as follows: attapulgite powder is added to an N-methylpyrrolidone solution and ultrasonically dispersed for 30–60 min to form a suspension with a concentration of 0.20–0.35 g / mL; under nitrogen protection, the suspension is heated to 50–70 °C, and terephthalic diisocyanate is added, and the mixture is stirred and refluxed at 100–200 r / min for 6–12 h; the temperature is then raised to 90–110 °C, cyclohexane-1,2-dicarboxylic anhydride is added, and the mixture is stirred and refluxed at 100–200 r / min for 4–8 h to complete the reaction; after the reactants are cooled to room temperature, they are filtered, washed, and dried to obtain the modified attapulgite. The preparation method of low-polymer water-resistant polyvinyl acetate is as follows: (1) Add polyvinyl alcohol to deionized water, heat to 95-100℃, and stir continuously at 200-400 r / min until the polyvinyl alcohol is completely dissolved. After cooling to room temperature, add an appropriate amount of sodium acetate to adjust the pH value to 4.8-5.1 to obtain a polyvinyl alcohol solution; (2) Add azobisisobutyronitrile to the vinyl acetate monomer, stir thoroughly to disperse it in the monomer, and divide the monomer into two parts with a volume ratio of 1: 2; (3) Heat the polyvinyl alcohol solution to 65-75°C, add the smaller volume of monomer to the polyvinyl alcohol solution, and stir at 100-200 r / min for 20-40 min; continue stirring, and add the remaining monomer to the polyvinyl alcohol solution at a dropping rate of 1-2 mL / min. After the addition is complete, keep warm for 1-2 h, and let it cool to room temperature. Pass it through a 50-100 mesh sieve, wash it with anhydrous ethanol, and dry it at 60-70°C to obtain oligomeric water-resistant polyvinyl acetate; The modified ceramic powder is prepared by mixing ceramic powder, γ-methacryloxypropyltrimethoxysilane and anhydrous ethanol, stirring at 400-800 r / min for 10-20 min, and drying the mixture at 50-60℃ until the anhydrous ethanol is completely evaporated to obtain the modified ceramic powder.

2. The method for preparing a surface veneer for a decorative wood panel according to claim 1, characterized in that: The modified attapulgite comprises the following components: by weight: 8-14 parts attapulgite powder, 7-9 parts terephthalic diisocyanate, and 7-8 parts cyclohexane-1,2-dicarboxylic anhydride.

3. The method for preparing a surface veneer for a decorative wood panel according to claim 1, characterized in that: The preparation of the adhesive includes the following steps: S1: Attapulgite was grafted with terephthalic diisocyanate and cyclohexane-1,2-dicarboxylic anhydride to obtain modified attapulgite. S2: Mix oligomeric water-resistant polyvinyl acetate, vinyl acetate, modified ceramic powder, sodium thiosulfate, sodium hydroxide, urea, and water evenly to obtain white latex. S3: Mix the modified attapulgite, urea-formaldehyde resin, white glue and curing agent evenly to obtain the adhesive.

4. The method for preparing a surface veneer for a decorative wood panel according to claim 1, characterized in that: The mass ratio of polyvinyl alcohol and vinyl acetate monomers is 1:(2-6); the amount of azobisisobutyronitrile added is 0.6% to 1% of the mass of vinyl acetate monomers.

5. A decorative wood panel prepared by the method for preparing a surface veneer for a decorative wood panel according to any one of claims 1 to 4.

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