Antibacterial material based on visible light catalysis and preparation method and application thereof

Abstract

The invention discloses an antibacterial material based on visible light catalysis and a preparation method and application thereof. The antibacterial material based on visible light catalysis is prepared by taking bismuth nitrate, urea and glucose as raw materials through reaction. The preparation method comprises the following steps: preparing melamine resin with a visible light catalysis antibacterial function by taking melamine as a raw material, reacting the melamine resin with a formaldehyde solution, melamine and urea to prepare the melamine resin with the visible light catalysis antibacterial function, dipping a facing material into the melamine resin, and drying and pressing to obtain the facing plate with the visible light catalysis antibacterial function. And the prepared facing plate has a good antibacterial effect on escherichia coli, staphylococcus aureus and streptococcus albus. Therefore, the prepared antibacterial material based on visible light catalysis can improve the comprehensive performance of a surface decoration wood board, provides a good surface antibacterial function for a facing decoration material, and improves various physical and chemical properties of the facing decoration material; and important practical significance is achieved for high-quality development of the artificial board industry and improvement of the living environment quality of people.

Description

Technical Field

[0001] The invention relates to the technical field of photocatalytic antibacterial materials and wooden decorative materials manufacturing, and in particular to an antibacterial material based on visible light catalysis and a preparation method and application thereof. Background Art

[0002] With the continuous improvement of living standards, the output and consumption of surface decorative wood panels (hereinafter referred to as veneers) have increased year by year. Veneers are made by covering the surface of various wood panels such as plywood, particleboard, fiberboard, blockboard, etc. with wood flakes, impregnated film paper or high-pressure decorative panels. In order to improve the surface performance of veneers, the veneer materials are often impregnated with resin before pressing. Among them, melamine resin is the most commonly used resin material for impregnation treatment. It is a thermosetting amino resin synthesized from melamine and formaldehyde as the main raw materials. It has the advantages of high hardness of the cured glue layer, good water resistance, high thermal stability and colorless and transparent glue layer.

[0003] As people's requirements for health and environmental protection become higher and higher, green, environmentally friendly, healthy and fresh decorative materials have become people's first choice, and the antibacterial properties of decorative materials have also been increasingly valued. Therefore, the research and development of furniture and decorative materials with excellent antibacterial functions is one of the main trends in the future development of the home improvement industry, and will also become a new growth point in the home improvement market. It has important practical significance for the high-quality development of the wood decorative materials industry and the improvement of people's living environment quality. At present, according to the effective ingredients in antibacterial materials, they can be divided into three categories: natural antibacterial materials, organic antibacterial materials and inorganic antibacterial materials. Among them, the advantage of natural antibacterial materials is that they are extracted from natural substances or used directly. During the production and use process, they generally do not pollute and harm the environment and people, and most of them have broad-spectrum antibacterial properties. However, the application of natural plant antibacterial in the field of decorative panel processing is relatively small, mainly because the production process of wood panels requires drying, hot pressing and other processes, and the effective ingredients of natural extracts are easily destroyed during the preparation process. At the same time, the addition of additives may also affect the surface properties and coating process of decorative materials. Quaternary ammonium salts and halogenated amines in organic antimicrobial agents have poor thermal stability, are prone to drug resistance, and cannot guarantee a stable storage period. They are prone to produce harmful substances after decomposition, which is not conducive to their application in decorative panels. From an environmental and practical perspective, inorganic antimicrobial agents have better antimicrobial effects and are more suitable types of antimicrobial agents with good application development potential. However, the commonly used zinc, silver, and copper inorganic antimicrobial agents, or loaded metal particles, are expensive, easily cause photocatalytic discoloration of the base material, or have the risk of heavy metal enrichment that harms health.

[0004] In the prior art, the paper "Study on the Antibacterial Properties of Melamine Formaldehyde Composite Resins" (Ni Jiarui, Shandong Agricultural University, May 2024) discloses PAM-melamine formaldehyde resin, and its preparation method is: after the formaldehyde solution and water are mixed, alkali is added to adjust the pH, and then PAM (photocatalytic antibacterial agent) is added to heat it to 85 ° C and then kept warm. When the hydrophobic temperature reaches 30 ° C, ethanol is added, and after cooling, alkali is added to adjust the pH to 9.0 to obtain the final product. The PAM-melamine formaldehyde resin can be used to impregnate decorative paper veneer particleboard, and after its impregnation treatment, the antibacterial ability, bonding strength, wear resistance, crack resistance, thermal stability, and formaldehyde release of the board are reduced. However, the cross-linking density of the above-mentioned PAM-melamine formaldehyde resin after curing is large, resulting in high brittleness and short storage period, and it only has good antibacterial effects on Escherichia coli and Staphylococcus aureus, and does not have a good antibacterial effect on white streptococci. CN119073327A discloses a chiral multi-level antibacterial film and its preparation method and application, wherein the antibacterial film is prepared from a first component (bismuth nitrate), a second component, a chiral inducing agent (glucose), a substrate and / or a nucleation control agent (urea). However, the antibacterial film has the disadvantages of slow antibacterial speed, poor stability and limited range of action.

[0005] Therefore, it is necessary to develop an efficient and practical inorganic antibacterial material based on visible light catalysis and use it in the field of wood board surface decoration to ensure that the prepared wood boards have good antibacterial effects on Streptococcus albus, Escherichia coli and Staphylococcus aureus, which has important practical significance for the high-quality development of the wood decoration materials industry and the improvement of people's living environment quality. Summary of the invention

[0006] In view of the above-mentioned prior art, the purpose of the present invention is to provide an antibacterial material based on visible light catalysis, and a preparation method and application thereof. The present invention uses bismuth nitrate, urea and glucose as raw materials to prepare an antibacterial material based on visible light catalysis through a hydrothermal reaction. The prepared antibacterial material based on visible light catalysis is reacted with formaldehyde solution, melamine and urea to prepare a melamine resin with visible light catalytic antibacterial function, and then the finishing material is impregnated in the above-mentioned melamine resin, and after drying and pressing, a finishing board material with visible light catalytic antibacterial function is obtained. The antibacterial material based on visible light catalysis prepared by the present invention can improve the antibacterial properties and physical and chemical properties of melamine resin and surface decorative wood boards.

[0007] To achieve the above object, the present invention adopts the following technical solution:

[0008] The first aspect of the present invention provides a method for preparing an antibacterial material based on visible light catalysis, comprising the following steps:

[0009] Urea solution and glucose solution are sequentially added to a bismuth nitrate dilution to obtain a mixed solution, alkali is added to the mixed solution to adjust the pH value and then a hydrothermal reaction is carried out. After the reaction is completed, the mixed solution is filtered, and the filtered solid is collected, washed, and dried to obtain an antibacterial material based on photocatalysis.

[0010] Preferably, the bismuth nitrate dilution is obtained by mixing a bismuth nitrate solution and a nitric acid solution in a volume ratio of 1:1 and stirring for 10-20 minutes, wherein the concentration of the bismuth nitrate solution is 1 mol / L and the concentration of the nitric acid solution is 1 mol / L.

[0011] Preferably, the volume ratio of the bismuth nitrate diluent, the urea solution and the glucose solution is (1.5-2.5):1:1.

[0012] Preferably, the mass fraction of the urea solution is 1%-10%, and the mass fraction of the glucose solution is 1%-5%.

[0013] Preferably, alkali is added to adjust the pH to 8.0-9.0, and the alkali is sodium hydroxide solution, and the concentration of the sodium hydroxide solution is 2 mol / L.

[0014] Preferably, the hydrothermal reaction temperature is 150-180° C., and the hydrothermal reaction time is 1-5 h.

[0015] Preferably, the drying temperature is 50-70° C. and the drying time is 8-12 h.

[0016] The second aspect of the present invention provides an antibacterial material based on visible light catalysis prepared by the above preparation method.

[0017] The third aspect of the present invention provides the use of the above-mentioned antibacterial material based on visible light catalysis in the preparation of melamine resin with visible light catalytic antibacterial function and / or the preparation of surface decorative wooden board with visible light catalytic antibacterial function.

[0018] In a fourth aspect of the present invention, a melamine resin having visible light catalytic antibacterial function is provided, which is prepared by the following method:

[0019] (1) adding alkali to the formaldehyde solution to adjust the pH for the first time, and then sequentially adding an antibacterial material based on visible light catalysis, melamine and urea to obtain a mixed solution;

[0020] (2) The mixed solution is heated up, and when the hydrophobic temperature of the mixed solution reaches 25-35° C., ethanol is added and the temperature is lowered, and then alkali is added to adjust the pH for the second time, thereby obtaining a melamine resin with visible light catalytic antibacterial function.

[0021] Preferably, in step (1), the mass fraction of the formaldehyde solution is 35%-55%.

[0022] Preferably, the alkali is a sodium hydroxide solution with a mass fraction of 5-30%, and the pH is adjusted to 8.0-9.0 for the first time and to 9.0 for the second time.

[0023] Preferably, in step (1), the mass ratio of formaldehyde solution, antibacterial material based on visible light catalysis, melamine and urea is (200-280): (0.03-0.09): (82-126): (24-42).

[0024] Preferably, in step (2), the temperature raising treatment is: heating the mixed solution to raise its temperature to 85° C. within 20-30 minutes, and keeping it warm for 30 minutes.

[0025] Preferably, in step (2), the amount of ethanol added is 10%-25% of the mass of the melamine resin.

[0026] Preferably, in step (2), the cooling treatment is as follows: after adding ethanol, the temperature is rapidly lowered to 60-70°C and kept warm for 30 minutes, and then immediately cooled to 35-45°C.

[0027] In a fifth aspect of the present invention, there is provided a surface decorative wood board having visible light catalytic antibacterial function, which is prepared by the following method:

[0028] The finishing material is impregnated in melamine resin with visible light catalytic antibacterial function, and dried to obtain the impregnated finishing material; the impregnated finishing material is then applied to the surface of the wooden board and pressed to obtain the finishing board with visible light catalytic antibacterial function.

[0029] Preferably, the facing material is one of impregnated film paper, high-pressure decorative board, and decorative veneer / thin wood.

[0030] Preferably, the impregnation amount of the melamine resin having visible light catalytic antibacterial function in the finishing material is 50-200%.

[0031] Preferably, the drying method is natural air drying, kiln drying or dryer drying.

[0032] Preferably, the water content of the impregnated facing material is 5%-20%.

[0033] Preferably, the pressing temperature is 25-250° C., the pressing pressure is 0.5 MPa-12.0 MPa, and the pressing time is 20-2500 s.

[0034] Beneficial effects of the present invention:

[0035] The present invention uses bismuth nitrate, urea and glucose as raw materials to prepare an antibacterial material based on visible light catalysis through a hydrothermal reaction, and then reacts the prepared antibacterial material based on visible light catalysis with a formaldehyde solution, melamine and urea to prepare a melamine resin with a visible light catalytic antibacterial function. The facing material is impregnated in the above melamine resin, dried for standby use, and then the facing material is pressed onto the surface of a wooden board to obtain a facing board with a visible light catalytic antibacterial function. Among them, bismuth nitrate is used as a bismuth source, urea is used as a stabilizer, and glucose is used as a reducing agent to prepare the antibacterial material based on visible light catalysis.

[0036] The present invention uses inorganic materials bismuth nitrate, urea and glucose to prepare an antibacterial material based on visible light catalysis, which has the advantages of good antibacterial property, visible light catalysis, stable properties, low cost, and no effect on the decorative effect of the product. At the same time, it is combined with melamine resin to prepare a melamine resin with visible light catalytic antibacterial function, and the above melamine resin is used to impregnate decorative materials. It can be seen that the antibacterial material based on visible light catalysis prepared by the present invention can improve the comprehensive performance of melamine resin and surface decorative wood board, provide good surface antibacterial function and various physical and chemical properties of the finishing decorative material, and has important practical significance for the high-quality development of the wood-based panel industry and the improvement of people's living environment quality. DETAILED DESCRIPTION

[0037] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0038] In the prior art, although it is disclosed that bismuth nitrate, glucose and urea are used as raw materials to prepare antibacterial films, the prepared antibacterial films are based on chiral multi-level structures to regulate bacterial adhesion behavior. Because it mainly relies on direct contact with bacteria to play a role, that is, it only has a regulatory effect on bacteria attached to the surface of the film and the surrounding area, and its chiral multi-level structure is easily affected by external friction or chemical corrosion during use, resulting in structural damage, thereby affecting its ability to regulate bacterial adhesion behavior, and the chiral multi-level structure regulates bacterial adhesion behavior and controls the interaction between bacteria and the surface of the antibacterial film on the biofilm, and undergoes a series of reactions to change the adhesion behavior. This process is relatively slow and it takes a long time to see obvious effects. In addition, although it is disclosed that formaldehyde, photocatalytic antibacterial agent, alkali and ethanol are used as raw materials to prepare PAM-melamine formaldehyde resin, and it is used to impregnate decorative paper veneer panels to improve the antibacterial properties of veneer panels. However, the above-mentioned PAM-melamine formaldehyde resin only has a certain antibacterial effect on Escherichia coli and Staphylococcus aureus, while the decorative panel itself contains organic matter and has a certain water absorption, which is easy to breed white streptococci.

[0039] Based on this, the present invention provides an antibacterial material based on visible light catalysis, and a preparation method and application thereof. The present invention uses bismuth nitrate, urea and glucose as raw materials to prepare an antibacterial material based on visible light catalysis through a hydrothermal reaction, and then reacts the prepared antibacterial material based on visible light catalysis with a formaldehyde solution, melamine and urea to prepare a melamine resin with visible light catalytic antibacterial function. The finishing material is immersed in the above-mentioned melamine resin, dried for standby use, and then the finishing material is pressed onto the surface of a wooden board to obtain a finishing board with visible light catalytic antibacterial function. Among them, bismuth nitrate is used as a bismuth source, urea is used as a stabilizer, and glucose is used as a reducing agent to prepare an antibacterial material based on visible light catalysis.

[0040] The antibacterial material based on visible light catalysis prepared by the present invention can achieve antibacterial effect by using natural light, while traditional antibacterial materials either have no photocatalytic function or have photocatalytic function but need to use ultraviolet light instead of natural light for antibacterial, so their practical application is limited.

[0041] Therefore, for decorative materials, being able to use natural light for antibacterial purposes is a very convenient function. In addition, in the process of preparing melamine resin with visible light catalytic antibacterial function, urea is used, which can reduce the cross-linking degree of the melamine resin after curing, thereby reducing the brittleness of the resin and prolonging durability. After curing, pure melamine resin has a high cross-linking density, which makes the glue layer very brittle and prone to cracks in practical applications. The addition of urea can also prolong the storage period of melamine resin. The storage period of pure melamine resin is only about 2 days, which can be extended to 4-5 days after adding urea, better meeting production requirements.

[0042] The antibacterial material based on visible light catalysis prepared by the present invention can improve the comprehensive performance of melamine resin and surface decorative wood board, and provide good surface antibacterial function and improvement of various physical and chemical properties for the decorative decorative material. The surface decorative wood board prepared by the present invention has good antibacterial effect on Escherichia coli, Staphylococcus aureus and Streptococcus albus. In principle, since the antibacterial material based on photocatalysis prepared by the present invention is a kind of micro-sized flaky particles, it has many micro-pores and has a physical adsorption effect on formaldehyde molecules, so it can play a role in reducing the release of free formaldehyde in melamine resin and formaldehyde in decorative board. At the same time, it also presents a certain negative charge, and electrostatic adsorption occurs with positively charged components (such as amino groups) in melamine resin molecules, which can play a role in enhancing the cohesion of resin, thereby affecting the mechanical properties of resin, such as tensile strength, surface bonding strength, etc. In addition, the antibacterial material particles in melamine resin play a certain filling role on the surface of decorative material, which can improve the surface properties of decorative material, such as wear resistance. Therefore, the viscosity and solid content of melamine resin can be increased and the free methanol content can be reduced by modifying the antibacterial material based on visible light catalysis. At the same time, it can be used to prepare surface decorative wood boards to improve the tensile strength and surface bonding strength of wood boards and reduce surface wear value and formaldehyde emission.

[0043] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.

[0044] The experimental materials used in the embodiments of the present invention are all conventional experimental materials in the art and can be purchased through commercial channels.

[0045] Example 1: Preparation method of antibacterial material based on visible light catalysis

[0046] 1M bismuth nitrate solution and 1M nitric acid solution were mixed in a volume ratio of 1:1, and stirred for 15 minutes to obtain a bismuth nitrate dilution solution;

[0047] Adding 1% urea solution and 1% glucose solution in sequence to the bismuth nitrate dilution, stirring until completely dissolved, to obtain a mixed solution; wherein the volume ratio of the bismuth nitrate dilution, the urea solution and the glucose solution is 2:1:1;

[0048] A sodium hydroxide solution with a mass fraction of 2 mol / L was added to the mixed solution until the pH value reached 9.0, and a hydrothermal reaction was carried out at 160°C for 2 hours. After the reaction was completed, the mixture was filtered, washed, and dried at 60°C for 10 hours to obtain an antibacterial material based on visible light catalysis.

[0049] Example 2: Preparation method of melamine resin with visible light catalytic antibacterial function

[0050] After adding a sodium hydroxide solution with a mass fraction of 25% to a formaldehyde solution with a mass fraction of 37% to adjust the pH to 8.5, the antibacterial material based on visible light catalysis prepared in Example 1, melamine and urea were added in sequence to obtain a mixed solution, wherein the added amount ratio of the formaldehyde solution, the antibacterial material based on visible light catalysis, melamine and urea was 243g:0.07g:106g:30g;

[0051] The mixed solution was heated to 85°C within 25 minutes and kept warm for 30 minutes, and the hydrophobic temperature of the mixed solution was detected. When the hydrophobic temperature of the mixed solution reached 30°C, ethanol was added and the temperature was rapidly reduced to 65°C. After keeping warm for 30 minutes, it was immediately cooled to 40°C, wherein the amount of ethanol added was 20% of the mass of the melamine resin, and then a 25% by mass sodium hydroxide solution was added to adjust the pH to 9.0, and the mixture was filtered and the solid collected was the melamine resin with visible light catalytic antibacterial function.

[0052] Example 3: Preparation method of surface decorative wood board with visible light catalytic antibacterial function

[0053] Decorative paper is used as a finishing material, and the finishing material is impregnated in the melamine resin with visible light catalytic antibacterial function prepared in Example 2 until the impregnation amount is 150%, and naturally air-dried until the moisture content of the finishing material is 15.5%, to obtain impregnated decorative paper; the above-mentioned impregnated finishing material is applied to the surface of a wooden board, and pressed for 35 seconds under the conditions of 140°C and 1.1MPa to obtain a visible light catalytic antibacterial melamine resin impregnated paper decorative board, that is, a surface decorated wooden board with visible light catalytic antibacterial function.

[0054] Example 4: Preparation method of surface decorative wood board with visible light catalytic antibacterial function

[0055] Use wood veneer / thin wood as a finishing material, impregnate the finishing material in the melamine resin with visible light catalytic antibacterial function prepared in Example 2 until the impregnation amount is 90%, and naturally air-dry until the moisture content of the finishing material is 15.5%, to obtain impregnated decorative paper; apply the above-mentioned impregnated finishing material to the surface of the wooden board, press for 6 minutes under the conditions of 130°C and 1.1MPa, to obtain a visible light catalytic antibacterial melamine resin impregnated veneer decorative board, that is, a surface decorated wooden board with visible light catalytic antibacterial function.

[0056] Example 5: Preparation method of surface decorative wood board with visible light catalytic antibacterial function

[0057] The decorative paper is impregnated in the melamine resin with visible light catalytic antibacterial function prepared in Example 2 until the impregnation amount is 120%, and the paper is naturally air-dried until the water content of the decorative material is 15.5%, thereby obtaining the impregnated decorative paper; the paper is mixed with other impregnated decorative papers and loaded into a hot press, and hot-pressed at 8 MPa and 140° C. for 30 minutes to obtain a high-pressure decorative board impregnated with the visible light catalytic antibacterial melamine resin;

[0058] The high-pressure decorative board impregnated with the visible light catalytic antibacterial melamine resin is applied to the surface of the wooden board, and pressed for 6 minutes at 130°C and 1.1MPa to obtain the high-pressure decorative board veneer impregnated with the visible light catalytic antibacterial melamine resin, which is a surface decorative wooden board with visible light catalytic antibacterial function.

[0059] Comparative Example 1: Preparation method of melamine resin

[0060] The difference between this comparative example and Example 2 is that no antibacterial material based on visible light catalysis is added. The specific steps are:

[0061] After adding 25% sodium hydroxide solution to a 37% formaldehyde solution to adjust the pH to 8.5, melamine and urea are added to obtain a mixed solution, wherein the added amount ratio of formaldehyde solution, melamine and urea is 243g:106g:30g. The mixed solution is heated to 85°C within 25 minutes and kept warm for 30 minutes, and the hydrophobic temperature of the mixed solution is detected. When the hydrophobic temperature of the mixed solution reaches 30°C, ethanol is added and the temperature is quickly reduced to 65°C. After keeping warm for 30 minutes, it is immediately cooled to 40°C, wherein the amount of ethanol added is 20% of the mass of the melamine resin, and then a 25% sodium hydroxide solution is added to adjust the pH to 9.0, and the solid is collected by filtering, which is the melamine resin.

[0062] Comparative Example 2: Preparation method of melamine resin impregnated paper decorative board

[0063] The difference between this comparative example and Example 3 is that the facing material is immersed in the melamine resin prepared in Comparative Example 1.

[0064] Comparative Example 3: Preparation method of melamine resin impregnated paper decorative board

[0065] The difference between this comparative example and Example 4 is that the facing material is immersed in the melamine resin prepared in Comparative Example 1.

[0066] Comparative Example 4: Preparation of melamine resin impregnated high-pressure decorative board veneer

[0067] The difference between this comparative example and Example 5 is that the decorative paper is impregnated in the melamine resin prepared in Comparative Example 1.

[0068] Test Example 1:

[0069] According to GB / T 14074-2017 “Test Methods for Wood Adhesives and Resins”, the basic properties of the melamine resin with visible light catalytic antibacterial function prepared in Example 2 and the melamine resin prepared in Comparative Example 1 were tested, wherein the basic properties include viscosity, solid content, storage life and free formaldehyde content. The results are shown in Table 1.

[0070] Table 1 Melamine resin with visible light catalytic antibacterial function and basic properties of melamine resin

[0071]

[0072] As can be seen from Table 1, the viscosity, solid content and storage period of the melamine resin with visible light catalytic antibacterial function prepared in Example 2 and the melamine resin prepared in Comparative Example 1 are similar, but the free formaldehyde content of the melamine resin with visible light catalytic antibacterial function is 0.04%, while the free formaldehyde content of the melamine resin is 0.10%. It can be seen that by adding the antibacterial material based on photocatalysis prepared in the present invention to the melamine resin, the free formaldehyde content can be significantly reduced, and the environmental protection performance of the resin material is improved.

[0073] Test Example 2:

[0074] According to GB / T 17657-2022 "Test methods for physical and chemical properties of wood-based panels and veneer wood-based panels", GB / T 39600-2021 "Classification of formaldehyde emission of wood-based panels and their products" and LY / T 1143-2006 "Impregnated adhesive paper for veneer", the physical and chemical properties of the surface decorative wood boards prepared in Examples 3-5 and Comparative Examples 2-4 were tested, where the physical and chemical properties include tensile strength, surface bonding strength, surface abrasion value, surface crack resistance and formaldehyde emission. The results are shown in Table 2.

[0075] Table 2 Physical and chemical properties of impregnated facing materials and surface decorative wood panels

[0076]

[0077] As can be seen from Table 2, the same facing material is impregnated in the melamine resin prepared in Comparative Example 1 and the melamine resin with visible light catalytic antibacterial function prepared in the present invention. Compared with the melamine resin, the melamine resin with visible light catalytic antibacterial function of the present invention is used to impregnate the facing material, which can improve the tensile strength and surface bonding strength of the surface decorative wood board obtained, and reduce the surface wear value and formaldehyde emission. Among them, the formaldehyde emission of Comparative Examples 3-5 can reach the E0 level requirement, while the formaldehyde emission of Comparative Examples 2-4 can only reach the E1 level requirement.

[0078] Test Example 3:

[0079] According to LY / T 1926-2020 "Testing and grading of antibacterial properties of artificial boards and wood (bamboo) products", the antibacterial properties of the surface decorative wood boards prepared in Examples 3-5 and Comparative Examples 2-4 were tested. During the test, the samples were treated with light protection and visible light, respectively, to explore the antibacterial effects on Escherichia coli, Staphylococcus aureus and Streptococcus albus under different light conditions. The results are shown in Tables 3 and 4.

[0080] Table 3 Antibacterial properties of surface decorative wood panels under light-shielding treatment

[0081]

[0082]

[0083] Table 4 Antibacterial properties of surface decorative wood panels treated with visible light

[0084]

[0085] It can be seen from Tables 3 and 4 that the antibacterial rates of surface decorative wood panels without visible light treatment (light-avoiding treatment) against Escherichia coli, Staphylococcus aureus and Streptococcus albus are all less than 90%, which does not meet the requirements of antibacterial grade I and II in "Testing and Classification of Antibacterial Properties of Artificial Boards and Wood (Bamboo) Products" LY / T 1926-2020, and does not have antibacterial function. After visible light treatment, the antibacterial rates of surface decorative wood panels prepared by the present invention against Escherichia coli, Staphylococcus aureus and Streptococcus albus all reached more than 99%, all of which had strong antibacterial effects and had certain broad-spectrum antibacterial properties. However, in Comparative Examples 2-4, the antibacterial rates of surface decorative wood panels impregnated with only melamine resin against Escherichia coli, Staphylococcus aureus and Streptococcus albus were less than 90%, which did not meet the requirements of antibacterial grade I and II in the above standards, and did not have antibacterial function. It can be seen that the surface decorative wood panels prepared by the present invention exhibit good antibacterial properties under visible light catalysis.

[0086] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing an antibacterial material based on visible light catalysis, characterized in that: The following steps are involved: Urea solution and glucose solution are sequentially added to a bismuth nitrate dilution solution, and the mixture is mixed to obtain a mixed solution; alkali is added to the mixed solution to adjust the pH value, and then a hydrothermal reaction is carried out. After the reaction is completed, the mixed solution is filtered, and the filtered solid is collected, washed, and dried to obtain an antibacterial material based on photocatalysis.

2. The method for preparing an antibacterial material based on visible light catalysis according to claim 1, characterized in that: The bismuth nitrate dilution is prepared by mixing a bismuth nitrate solution and a nitric acid solution in a volume ratio of 1:1, wherein the concentration of the bismuth nitrate solution is 1 mol / L, and the concentration of the nitric acid solution is 1 mol / L; The volume ratio of the bismuth nitrate diluent, the urea solution and the glucose solution is (1.5-2.5):1:1; the mass fraction of the urea solution is 1%-10%, and the mass fraction of the glucose solution is 1%-5%.

3. The method for preparing an antibacterial material based on visible light catalysis according to claim 1, characterized in that: The hydrothermal reaction temperature is 150-180°C, the hydrothermal reaction time is 1-5h, and alkali is added to adjust the pH to 8.0-9.

0.

4. An antibacterial material based on visible light catalysis obtained by the preparation method according to any one of claims 1 to 3.

5. Use of the antibacterial material based on visible light catalysis according to claim 4 in the preparation of melamine resin with visible light catalytic antibacterial function and / or the preparation of surface decorative wooden board with visible light catalytic antibacterial function.

6. A melamine resin having visible light catalytic antibacterial function, characterized in that: Prepared by the following method: (1) adding alkali to the formaldehyde solution to adjust the pH for the first time, and then sequentially adding the antibacterial material based on visible light catalysis according to claim 4, melamine and urea to obtain a mixed solution; (2) The mixed solution is heated up, and when the hydrophobic temperature of the mixed solution reaches 25-35° C., ethanol is added and the temperature is lowered, and then alkali is added to adjust the pH for the second time, thereby obtaining a melamine resin with visible light catalytic antibacterial function.

7. The melamine resin having visible light catalytic antibacterial function according to claim 6, characterized in that: The mass ratio of formaldehyde solution, antibacterial material based on visible light catalysis, melamine and urea is (200-280): (0.03-0.09): (82-126): (24-42); The mass fraction of the formaldehyde solution is 35%-55%; the alkali is a sodium hydroxide solution with a mass fraction of 5-30%. The pH is adjusted to 8.0-9.0 for the first time and to 9.0 for the second time.

8. The melamine resin having visible light catalytic antibacterial function according to claim 6, characterized in that: In step (2), the temperature raising treatment is as follows: heating the mixed solution to 85°C within 20-30 minutes and keeping the temperature for 30 minutes; the temperature lowering treatment is as follows: after adding ethanol, rapidly cooling the mixture to 60-70°C and keeping the temperature for 30 minutes, and then immediately cooling the mixture to 35-45°C.

9. A surface decorative wood board with visible light catalytic antibacterial function, characterized in that: Prepared by the following method: The finishing material is impregnated in the melamine resin with visible light catalytic antibacterial function as described in any one of claims 6-8, and dried to obtain the impregnated finishing material; the impregnated finishing material is then applied to the surface of the wooden board and pressed to obtain the finishing board with visible light catalytic antibacterial function.

10. The surface decorative wood board with visible light catalytic antibacterial function as claimed in claim 9, characterized in that: The facing material is one of impregnated film paper, high-pressure decorative board, and decorative veneer / thin wood; the impregnation amount of melamine resin with visible light catalytic antibacterial function in the facing material is 50-200%; the water content of the impregnated facing material is 5%-20%.

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