Melamine adhesive, melamine decorative paper and composite multilayer board

Abstract

The invention provides a melamine adhesive, melamine decorative paper and a composite multilayer board. The melamine adhesive is prepared from the following components in parts by mass: 80 to 90 parts of melamine formaldehyde resin, 1 to 5 parts of curing agent, 0.03 to 0.5 part of dispersing agent, 2 to 5 parts of flaky silicon dioxide and 1 to 5 parts of wear-resistant filler. Through the design and mutual compounding of the components, especially through the synergistic effect of the flaky silicon dioxide and the wear-resistant filler, a facing layer and a base material can be jointly protected, so that the melamine decorative paper and the composite multilayer board adopting the melamine adhesive are high in hardness and have excellent surface wear resistance and scratch resistance, and the service life of the melamine decorative paper and the composite multilayer board is prolonged. And the cost is reduced while the product performance is improved.

Description

Technical Field

[0001] This invention belongs to the field of composite material technology, specifically relating to a melamine adhesive, melamine decorative paper, and composite multilayer board. Background Technology

[0002] Bathroom vanities are an essential bathroom product in modern life. The cabinet body and doors of bathroom vanities are generally made of wood panels. Among the many types of panels, multi-layer panels are affordable and are therefore widely used in economical and practical bathroom vanities.

[0003] Melamine multilayer board is one of the most commonly used boards for bathroom cabinets. It is characterized by its beauty, durability, and low cost. It is made by impregnating paper with different colors, patterns, or textures in melamine resin glue, then drying and curing it to form decorative paper. The decorative paper is then laid on the surface of the board (such as particleboard, moisture-resistant board, plywood, MDF, blockboard, medium-density fiberboard, multilayer board, etc.) and hot-pressed to form a decorative board. The quality of the decorative paper, the performance of the melamine resin glue, and the hot-pressing process all directly affect the quality of the finished melamine multilayer board.

[0004] Currently, the preparation of decorative paper mainly includes processes such as glue preparation, impregnation, drying, and cooling. The glue is mainly prepared by reacting melamine with formaldehyde to obtain melamine-formaldehyde resin, or by reacting urea with formaldehyde to obtain urea-formaldehyde resin, or by mixing melamine-formaldehyde resin and urea-formaldehyde resin. For example, CN107164992A discloses a method for preparing low-formaldehyde melamine impregnated paper, including the preparation of urea-formaldehyde glue resin, the preparation of melamine glue resin, primary impregnation, secondary impregnation, shearing, stacking, laying, and hot pressing. The raw materials for preparing the glue resin mainly include formaldehyde, urea, melamine, and formic acid. Environmentally friendly additives are added during the preparation of the glue resin, including at least one of curing agent, release agent, and penetrant, to formulate low-formaldehyde resin.

[0005] Although the manufacturing processes for decorative paper and melamine plywood are relatively mature, consumers' increasing demand for high-quality and low-cost home furnishings necessitates both excellent appearance and performance in bathroom cabinets made of plywood, while simultaneously requiring further cost reduction. Existing melamine plywood cannot adequately balance cost and product quality, particularly exhibiting significant shortcomings in abrasion and scratch resistance. Therefore, developing plywood with excellent abrasion and scratch resistance while maintaining low cost is a pressing issue in this field. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention provides a melamine adhesive, melamine decorative paper, and composite multilayer board. Through the component design and mutual compounding of the melamine adhesive, the composite multilayer board using it has high hardness, excellent surface wear resistance and scratch resistance, and lower cost while improving product performance.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a melamine adhesive, wherein the melamine adhesive comprises, by weight, the following components:

[0009] 80-90 parts of melamine-formaldehyde resin

[0010] 1-5 parts of curing agent

[0011] Dispersant 0.03-0.5 parts,

[0012] 2-5 parts of flake silica

[0013] 1-5 parts of wear-resistant filler.

[0014] This invention introduces wear-resistant fillers into melamine adhesives. These fillers, embedded within the resin, inhibit resin damage, scratching, or abrasion, effectively improving wear resistance and hardness, and enhancing scratch resistance. The flake-like silica contains abundant hydroxyl groups on its surface, allowing it to be uniformly dispersed in the resin matrix with the aid of a dispersant. Under certain temperatures (e.g., the heating conditions accompanying the processing of melamine decorative paper and multilayer composite boards), a small portion can chemically react with the melamine-formaldehyde resin, grafting it onto the resin. The flake-like silica possesses a certain rigidity, effectively improving the resin's hardness. Most of the unreacted flake-like silica remains uniformly dispersed in the resin, and after high-temperature pressing and curing, it enhances overall hardness and exhibits excellent rigidity, thus protecting the surface of melamine decorative paper and multilayer composite boards from damage by hard objects. Furthermore, the flake-like silica and the granular wear-resistant filler interact and work together to form a dense protective layer structure within the resin. When subjected to external friction, the two work synergistically to provide excellent wear resistance and scratch resistance. This invention, through the design and mutual compounding of components, especially through the synergistic effect of flake silica and wear-resistant fillers, can jointly protect the decorative layer and the substrate, making the melamine decorative paper and composite multilayer board using the melamine adhesive have high hardness, excellent surface wear resistance and scratch resistance, and lower cost while improving product performance.

[0015] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0016] In this invention, the melamine-formaldehyde resin has a mass fraction of 80-90 parts, for example, 81 parts, 82 parts, 83 parts, 84 parts, 85 parts, 86 parts, 87 parts, 88 parts or 89 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list the specific values ​​included in the range.

[0017] The curing agent is in the range of 1-5 parts by weight, for example, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0018] The mass fraction of the dispersant is 0.03-0.5 parts, for example, it can be 0.05 parts, 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts or 0.45 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0019] The sheet-like silica has a mass fraction of 2-5 parts, for example, 2.2 parts, 2.5 parts, 2.8 parts, 3 parts, 3.2 parts, 3.5 parts, 3.8 parts, 4 parts, 4.2 parts, 4.5 parts, or 4.8 parts.

[0020] The wear-resistant filler is 1-5 parts by weight, for example, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0021] As a preferred embodiment of the present invention, the curing agent includes organic acid anhydride curing agents, preferably any one or a combination of at least two of chain organic acid anhydride curing agents (e.g., linear organic acid anhydride curing agents), aromatic organic acid anhydride curing agents, and halogenated organic acid anhydride curing agents.

[0022] As a preferred embodiment of the present invention, the dispersant includes polyethylene glycol.

[0023] In this invention, the flake silica contains abundant hydroxyl groups, which are prone to agglomeration in melamine-formaldehyde resin. Polyethylene glycol is preferably used as a dispersant, which can improve the dispersibility of flake silica in melamine-formaldehyde resin, allowing it to better cooperate with wear-resistant fillers to jointly protect the decorative layer and substrate, and improve the wear resistance, scratch resistance and hardness of melamine decorative paper and composite multilayer board.

[0024] As a preferred embodiment of the present invention, the thickness of the sheet-like silicon dioxide is 0.1-1 μm, for example, it can be 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm or 0.98 μm, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0025] As a preferred embodiment of the present invention, the average aspect ratio of the sheet-like silica is 40-90, for example, it can be 45, 48, 50, 52, 55, 58, 60, 62, 65, 68, 70, 72, 75, 78, 80, 82, 85 or 88, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific point values ​​included in the range.

[0026] As a preferred embodiment of the present invention, the wear-resistant filler includes any one or a combination of at least two of alumina, quartz, and silicon carbide.

[0027] As a preferred embodiment of the present invention, the particle size of the wear-resistant filler is 150-300 mesh, for example, it can be 160 mesh, 180 mesh, 200 mesh, 230 mesh, 240 mesh, 250 mesh, 270 mesh, 280 mesh or 290 mesh, as well as specific particle values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific particle values ​​included in the range.

[0028] This invention has found that the particle size of the wear-resistant filler affects the improvement of wear resistance; when the filler particle size is small, it is difficult to effectively exert its wear-resistant effect. This invention preferably uses a 150-300 mesh wear-resistant filler, which is dispersed in the resin and has excellent wear resistance. Simultaneously, the flake-shaped silica provides surface protection, and it works synergistically with the wear-resistant filler to form a denser protective layer structure. When the surface is subjected to external friction or damage from hard objects, the two work together to protect the decorative layer and the substrate, significantly improving the wear resistance, scratch resistance, and hardness of melamine decorative paper and composite multilayer boards.

[0029] As a preferred embodiment of the present invention, the melamine adhesive further comprises 0.1-0.6 parts by weight of release agent, for example, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts, 0.5 parts or 0.55 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0030] As a preferred embodiment of the present invention, the release agent includes epoxy resin release agent and / or phenolic resin release agent.

[0031] As a preferred embodiment of the present invention, the melamine adhesive further includes 0.1-1 parts of penetrant by weight, for example, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts or 0.9 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0032] As a preferred embodiment of the present invention, the penetrant includes sulfonate penetrants, including but not limited to: sodium dioctyl maleate sulfonate.

[0033] As a preferred embodiment of the present invention, the melamine adhesive further includes 0.2-0.8 parts by weight of a brightening agent, for example, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts, 0.5 parts, 0.55 parts, 0.6 parts, 0.65 parts, 0.7 parts, or 0.75 parts, as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0034] As a preferred embodiment of the present invention, the brightening agent includes styrene-based brightening agents and / or acrylonitrile-based brightening agents.

[0035] As a preferred embodiment of the present invention, the melamine adhesive further includes 1-10 parts of softener by weight, for example, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts or 9 parts, as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0036] As a preferred embodiment of the present invention, the fabric softener includes polyacrylate fabric softeners.

[0037] In this invention, the polyacrylate-based fabric softener uses commercially available products, and its preparation monomers include, but are not limited to, any one or a combination of at least two of methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, and butyl acrylate.

[0038] As a preferred embodiment of the present invention, the melamine adhesive further includes 0.05-0.3 parts of wetting agent by weight, for example, 0.08 parts, 0.1 parts, 0.12 parts, 0.15 parts, 0.18 parts, 0.2 parts, 0.22 parts, 0.25 parts or 0.28 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0039] As a preferred embodiment of the present invention, the wetting agent includes any one or a combination of at least two of ethanol, propylene glycol, glycerol, and dimethyl sulfoxide.

[0040] As a preferred embodiment of the present invention, the melamine adhesive comprises the following components in parts by weight:

[0041] 80-90 parts of melamine-formaldehyde resin

[0042] 1-5 parts of curing agent

[0043] Dispersant 0.03-0.5 parts,

[0044] 2-5 parts of flake silica

[0045] 1-5 parts of wear-resistant filler

[0046] Release agent 0.1-0.6 parts,

[0047] Penetrating agent 0.1-1 part,

[0048] Brightening agent 0.2-0.8 parts,

[0049] Fabric softener 1-10 parts,

[0050] Wetting agent 0.05-0.3 parts.

[0051] In a second aspect, the present invention provides a melamine decorative paper, the melamine decorative paper comprising a base paper and a melamine adhesive as described in the first aspect attached to the base paper.

[0052] As a preferred embodiment of the present invention, the melamine adhesive is attached to the base paper after impregnation and drying.

[0053] Preferably, the base paper comprises melamine paper.

[0054] Preferably, the drying temperature is 50-80℃, for example, it can be 52℃, 55℃, 58℃, 60℃, 62℃, 65℃, 68℃, 70℃, 72℃, 75℃ or 78℃, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0055] Preferably, the drying time is 1-10 min, for example, it can be 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min or 9 min, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0056] Thirdly, the present invention provides a composite multilayer board, the composite multilayer board comprising melamine decorative paper as described in the second aspect.

[0057] As a preferred embodiment of the present invention, the composite multilayer board comprises a substrate, engineered wood veneer, and melamine decorative paper arranged sequentially.

[0058] As a preferred embodiment of the present invention, the substrate includes at least two single boards. For example, the number of single boards can be 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14 or 15, and preferably the substrate includes nine single boards.

[0059] Fourthly, the present invention provides a method for preparing a composite multilayer board as described in the third aspect, the method comprising:

[0060] After the engineered wood veneer and melamine decorative paper are stacked together, a first pressing is performed to obtain a composite layer;

[0061] The composite layer is laminated with the substrate, with the engineered wood veneer positioned between the melamine decorative paper and the substrate, and then a second lamination is performed to obtain the composite multilayer board.

[0062] As a preferred embodiment of the present invention, the temperature of the first pressing is 195-205℃, for example, it can be 196℃, 197℃, 198℃, 199℃, 200℃, 201℃, 202℃, 203℃ or 204℃, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0063] As a preferred embodiment of the present invention, the pressure of the first pressing is 11-13 MPa, for example, it can be 11.2 MPa, 11.5 MPa, 11.8 MPa, 12 MPa, 12.2 MPa, 12.5 MPa or 12.8 MPa, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0064] As a preferred technical solution of the present invention, the first pressing time is 5-15 s, for example, it can be 6 s, 7 s, 8 s, 9 s, 10 s, 11 s, 12 s, 13 s or 14 s, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific point values ​​included in the range.

[0065] As a preferred embodiment of the present invention, the temperature of the second pressing is 90-95℃, for example, it can be 90.5℃, 91℃, 91.5℃, 92℃, 92.5℃, 93℃, 93.5℃, 94℃ or 94.5℃, as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0066] As a preferred embodiment of the present invention, the pressure of the second pressing is 3-5 MPa, for example, it can be 3.2 MPa, 3.5 MPa, 3.8 MPa, 4 MPa, 4.2 MPa, 4.5 MPa or 4.8 MPa, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0067] As a preferred embodiment of the present invention, the second pressing time is 5-15 min, for example, it can be 6 min, 7 min, 8 min, 9 min, 10 min, 11 min, 12 min, 13 min or 14 min, as well as specific point values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific point values ​​included in the range.

[0068] In a preferred embodiment, the method for preparing the composite multilayer board employs a lamination process, comprising the following steps:

[0069] (1) After the engineered wood veneer and melamine decorative paper are stacked together, a first pressing is performed to obtain a composite layer; the conditions for the first pressing include: temperature 195-205℃, pressure 11-13 MPa, and time 5-15 s;

[0070] (2) The composite layer is stacked with the substrate, so that the engineered wood veneer is located between the melamine decorative paper and the substrate, and then a second pressing is performed to obtain the composite multilayer board; the conditions for the second pressing include: temperature 90-95℃, pressure 3-5MPa, and time 5-15 min.

[0071] The preparation of composite multilayer boards includes lamination and direct lamination processes, as described above. The direct lamination process involves first directly laminating engineered wood veneer to a substrate to obtain a direct-lamination substrate. The direct lamination conditions include: pressure of 11-13 MPa, temperature of 162-168℃, and time of 8 min, requiring high lamination standards. Then, melamine paper is pressed onto the direct-lamination substrate under the following conditions: pressure of 11-13 MPa, temperature of 130-135℃, and time of 1.7 min. The direct lamination process not only has high lamination requirements but also requires surface smoothing after lamination of the engineered wood veneer and substrate. This invention preferably uses the aforementioned lamination process, which eliminates the need for surface smoothing. Furthermore, the direct lamination of engineered wood veneer and melamine decorative paper results in higher production efficiency and lower material costs, achieving cost reduction and efficiency improvement.

[0072] Fifthly, the present invention provides an application of the composite multilayer board as described in the third aspect in furniture, bathroom fixtures, building materials or decorative materials;

[0073] As a preferred embodiment of the present invention, the composite multilayer board is applied to a bathroom cabinet.

[0074] Compared with the prior art, the present invention has at least the following beneficial effects:

[0075] (1) In the melamine adhesive provided by the present invention, through the design and mutual compounding of components, especially through the synergistic effect of flake silica and wear-resistant filler, the decorative layer and the substrate can be protected together, so that the melamine decorative paper and composite multilayer board using the melamine adhesive have high hardness, excellent surface wear resistance and scratch resistance, and reduce costs while improving product performance.

[0076] (2) The melamine adhesive is used to prepare melamine decorative paper and composite multilayer board, which is convenient for circulation and application in the workshop. It can better match the lamination process, making production efficiency higher, cost lower, and economic benefits improved, so as to achieve the purpose of cost reduction and efficiency improvement. Detailed Implementation

[0077] To facilitate understanding of the present invention, specific embodiments are provided to further illustrate the technical solution of the present invention. Those skilled in the art should understand that the embodiments are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0078] The following will use several embodiments as examples to describe in detail the melamine adhesive, melamine decorative paper, composite multilayer board and its preparation method according to the present invention, but the melamine adhesive, melamine decorative paper, composite multilayer board and its preparation method are not limited to these embodiments.

[0079] In the following examples, all raw materials used are commercially available chemicals, and specific information is as follows:

[0080] (1) Melamine-formaldehyde resin: brand name hk-1533, from Shandong Baihong New Materials Co., Ltd.;

[0081] (2) Curing agent: Aromatic organic acid anhydride curing agent, phthalic anhydride (PA), from Shandong Xuanhai Chemical Co., Ltd.;

[0082] (3) Dispersant: Polyethylene glycol, PEG-1000, from Haian Petrochemical Plant, Jiangsu Province;

[0083] (4) Sheet silica: 0.5 μm thick, with an average aspect ratio of 50, sourced from Shanghai Canal Materials Technology Co., Ltd.

[0084] Spherical silica: with a particle size of 12 μm, grade HB-139, from Hubei Huifu Nanomaterials Co., Ltd.;

[0085] (5) Wear-resistant filler: alumina, particle size of 200 mesh, grade DK410-2, from Beijing Deco Island Gold Technology Co., Ltd.;

[0086] (6) Release agent: Phenolic resin release agent, brand name DF-1020, from Dongguan Nuofeng Polymer Materials Co., Ltd.;

[0087] (7) Penetrant: Sodium dioctyl maleate sulfonate, penetrant T, from Shandong Taihe Technology Co., Ltd.;

[0088] (8) Brightening agent: Styrene-based brightening agent, from Shandong Youwang Chemical Products Co., Ltd.;

[0089] (9) Fabric softener: Polyacrylate fabric softener, sourced from Tianjin Damao Chemical Reagent Factory;

[0090] (10) Wetting agent: Ethanol, from Yueyang Junshuo Chemical Co., Ltd.

[0091] Examples 1-5, Comparative Examples 1-6

[0092] A melamine adhesive, the types and amounts of each component are shown in Table 1 and Table 2, and the unit of amount of each component is "parts" (parts by mass).

[0093] A melamine decorative paper and composite multilayer board using the aforementioned melamine adhesive are prepared by the following method:

[0094] (1) Mix the components of the melamine adhesive according to the formulas in Table 1 and Table 2, stir and disperse them evenly to make melamine adhesive;

[0095] (2) The melamine paper is immersed in the melamine adhesive obtained in step (1) for 40 seconds, and then baked at 130°C for 20 seconds to obtain melamine decorative paper.

[0096] (3) The engineered wood veneer and the melamine decorative paper obtained in step (2) are stacked and pressed together. The pressing conditions are: temperature 200℃, pressure 12 MPa, time 9 s, to obtain a composite layer.

[0097] The composite layer is stacked with the substrate (composed of 9 veneers) and then pressed together. The engineered wood veneer is located between the melamine decorative paper and the substrate. The pressing conditions are: temperature 95°C, pressure 4 MPa, and time 10 min, to obtain the composite multilayer board.

[0098] The performance testing of composite multilayer boards is conducted using the following methods:

[0099] (1) Abrasion resistance: According to the standard GB / T 17657-2022 Test Method for Physical and Chemical Properties of Wood-based Panels and Decorative Wood-based Panels 4.45 Surface abrasion resistance test, the surface was placed in a constant temperature and humidity chamber at 20℃ and 65% humidity until the mass was constant. 180# sandpaper was used to apply an external force of 4.9±0.2 N. Requirements: Pattern abrasion 100 r, solid color abrasion 350 r; Test results: Pattern: After abrasion 100 r, the pattern should be at least 50% intact or there should be no exposed base, and the abrasion amount should be ≤80 g; Solid color: After abrasion 350 r, there should be no exposed base, and the abrasion amount should be ≤80 g;

[0100] (2) Scratch resistance: According to GB / T 17657-2022 Test method for physical and chemical properties of wood-based panels and decorative wood-based panels, 4.42 Surface scratch resistance test, apply a force of 1.5 N with a diamond needle and load one circle; Requirement: After the test, there should be no more than 90% continuous scratches on the surface.

[0101] The test results are shown in Tables 1 and 2:

[0102] Table 1

[0103]

[0104] Table 2

[0105]

[0106] According to the performance test data in Table 1, the melamine adhesive provided by this invention incorporates flake silica and wear-resistant fillers. Through their synergistic effect, they can jointly protect the finishing layer and the substrate, resulting in high hardness of the composite multilayer board. The wear resistance at 350 r abrasion is ≤55 g, and there are no scratches at 1.5 N, demonstrating excellent performance in terms of surface wear resistance and scratch resistance. At the same time, the melamine adhesive is more convenient for use in the workshop and can be matched with the lamination process, resulting in high production efficiency of the composite multilayer board and reducing costs while improving product performance.

[0107] Comparing Tables 1 and 2, it can be seen that the melamine adhesive in Comparative Example 1 does not contain flake silica or wear-resistant filler, resulting in composite multilayer boards with low hardness and significantly poor wear and scratch resistance. The adhesives in Comparative Examples 2 and 4 contain only flake silica, while the adhesives in Comparative Examples 3 and 5 only contain wear-resistant filler. Although the wear and scratch resistance of the composite multilayer boards are improved compared to Comparative Example 1, they still cannot meet the surface performance requirements of the boards. The adhesive in Comparative Example 6 uses spherical silica, which improves wear and scratch resistance compared to Comparative Example 1, but still shows a significant difference compared to Examples 1-6, failing to meet the surface performance requirements of the boards. In summary, the present invention uses flake silica and wear-resistant filler in a specific ratio, which synergistically improve the wear and scratch resistance of melamine decorative paper and composite multilayer boards, enabling them to meet the surface performance requirements of the boards.

[0108] The present invention has been illustrated through the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A melamine adhesive, characterized by, The melamine adhesive comprises the following components by mass fraction: Melamine formaldehyde resin 80-90 parts, Curing agent 1-5 parts, Dispersant 0.03-0.5 parts, Flaky silica 2-5 parts, Wear-resistant filler 1-5 parts.

2. The melamine adhesive according to claim 1, characterized in that, The curing agent comprises an organic acid anhydride curing agent, preferably any one or a combination of at least two of a chain organic acid anhydride curing agent, an aromatic organic acid anhydride curing agent, and a halogenated organic acid anhydride curing agent; And / or, the dispersant comprises polyethylene glycol.

3. The melamine adhesive according to claim 1, characterized in that, The flaky silica has a thickness of 0.1-1 μm; And / or, the flaky silica has an average diameter-thickness ratio of 40-90; And / or, the wear-resistant filler comprises any one or a combination of at least two of alumina, quartz, and silicon carbide; And / or, the wear-resistant filler has a particle size of 150-300 mesh.

4. Melamine adhesive according to any of claims 1 to 3, characterized in that The melamine adhesive further comprises a release agent 0.1-0.6 parts by mass fraction; And / or, the release agent comprises an epoxy resin release agent and / or a phenolic resin release agent; And / or, the melamine adhesive further comprises a penetrating agent 0.1-1 parts by mass fraction; And / or, the penetrating agent comprises a sulfonate penetrating agent; And / or, the melamine adhesive further comprises a brightener 0.2-0.8 parts by mass fraction; And / or, the brightener comprises a styrene brightener and / or an acrylonitrile brightener; And / or, the melamine adhesive further comprises a softener 1-10 parts by mass fraction; And / or, the softener comprises a polyacrylate softener; And / or, the melamine adhesive further comprises a wetting agent 0.05-0.3 parts by mass fraction; And / or, the wetting agent comprises any one or a combination of at least two of ethanol, propylene glycol, glycerol, and dimethyl sulfoxide.

5. A melamine decorative paper, characterized by The melamine decorative paper comprises a base paper and the melamine adhesive as claimed in any one of claims 1-4 attached to the base paper.

6. The melamine decorative paper according to claim 5, characterized in that, The melamine adhesive is attached to the base paper after impregnation and drying; And / or, the base paper comprises a melamine paper.

7. A composite multi-ply board, characterized by The composite multi-layer board comprises the melamine decorative paper as claimed in claim 5 or 6.

8. The composite multi-ply sheet of claim 7, wherein, The composite multi-layer board comprises a base board, a technical veneer, and a melamine decorative paper arranged in sequence; And / or, the base board comprises at least 2 veneers.

9. A method of manufacturing a composite multi-ply board as claimed in claim 7 or 8, characterised in that, The preparation method comprises: Stacking the technical veneer and the melamine decorative paper to perform first pressing to obtain a composite layer; Stacking the composite layer and the base board with the technical veneer between the melamine decorative paper and the base board, and then performing second pressing to obtain the composite multi-layer board; And / or, the temperature of the first pressing is 195-205℃; And / or, the pressure of the first pressing is 11-13 MPa; And / or, the time of the first pressing is 5-15 s; And / or, the temperature of the second pressing is 90-95℃; And / or, the pressure of the second pressing is 3-5 MPa; And / or, the time of the second pressing is 5-15 min.

10. Use of the composite multi-layer board as claimed in claim 7 or 8 in furniture, bathroom, building materials, or decorative materials. Optionally, the composite multi-layer board is applied to a bathroom cabinet.

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