Moisture-proof and deformation-resistant melamine decorative plate and production process thereof

Abstract

The present application belongs to the technical field of building decoration materials, and particularly relates to a moisture-proof and anti-deformation melamine decorative plate and a production process. The moisture-proof and anti-deformation melamine decorative plate comprises, from bottom to top, a wood base material layer, a nano silicon resin coating layer, a melamine impregnated paper layer, a glass fiber mesh layer and a polyurethane resin layer. The production process of the melamine decorative plate comprises the following steps: (1) sequentially performing microwave drying, vacuum drying and hot air circulation treatment on the wood base material; (2) electrostatically spraying nano silicon resin and segmentally curing; (3) gradient hot pressing of the melamine impregnated paper; (4) plasma treatment of the glass fiber mesh and coating of a silane coupling agent; and (5) gradient ultraviolet curing of the polyurethane resin. The present application significantly improves the moisture-proof performance, greatly enhances the anti-deformation capability, effectively improves the interlayer bonding strength, comprehensively optimizes the coating and treatment process effects, and improves the overall wear resistance, hardness and appearance quality of the decorative plate.

Description

Technical Field

[0001] This invention belongs to the field of building decoration materials technology, specifically relating to a moisture-proof and deformation-resistant melamine decorative board and its production process. Background Technology

[0002] In the field of decorative materials, melamine decorative panels are widely used in furniture manufacturing, interior decoration, and many other applications due to their aesthetic appeal and durability. However, existing melamine decorative panels often face some technical problems that urgently need to be solved in practical use.

[0003] 1. Insufficient moisture resistance: Traditional melamine decorative boards lack precise control over the moisture content and density of the wood-based substrate, making them susceptible to moisture absorption. In high humidity environments, moisture easily penetrates the board, causing it to swell and deform, thus affecting its appearance and performance. For example, in humid southern regions, ordinary melamine decorative boards are prone to edge warping after a period of use, severely impacting the decorative effect.

[0004] 2. Limited resistance to deformation: The material composition and structural design of existing decorative panels' functional layers have defects, making them unable to effectively resist deformation caused by external factors. For example, in environments with large temperature variations, the panels will generate significant internal stress due to thermal expansion and contraction, leading to deformation and reducing the panel's dimensional stability. This not only affects the installation accuracy of the panels but may also cause gaps between adjacent panels, impacting the overall aesthetics.

[0005] 3. Poor bonding strength between layers: The lamination process between the layers is not perfect, resulting in insufficient interlayer bonding strength. During daily use, when subjected to external forces, the layers are prone to delamination, shortening the service life of the decorative panel. For example, during handling or installation, even slight impacts can cause the melamine-impregnated paper layer to separate from the other layers.

[0006] 4. Inadequate Coating and Processing: The coating materials and processing techniques used in some decorative panels fail to fully realize their protective and decorative functions. For example, traditional resin coatings may not effectively prevent moisture penetration, and their poor wear resistance makes them prone to wear and peeling during long-term use, affecting the aesthetics and protective performance of the decorative panels. Furthermore, the selection of process parameters for each layer of material is not optimized enough to fully improve material performance.

[0007] In summary, existing melamine decorative panels have shortcomings in terms of moisture resistance, deformation resistance, and interlayer bonding, making it difficult to meet the ever-increasing market demands. Therefore, developing a melamine decorative panel with excellent moisture resistance and deformation resistance is of great practical significance. Summary of the Invention

[0008] The purpose of this invention is to provide a moisture-proof and deformation-resistant melamine decorative board and its production process.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A moisture-proof and deformation-resistant melamine decorative board includes, from bottom to top, a wood substrate layer, a nano-silicone resin coating, a melamine-impregnated paper layer, a fiberglass mesh layer, and a polyurethane resin layer.

[0011] Wood substrate layer, moisture content ≤8%, density 800-850 kg / m³ 3 ;

[0012] The nano-silicone resin coating has a thickness of 0.18-0.22 mm and contains 15-17% phosphate-modified nano-alumina particles with a particle size of 65-75 nm.

[0013] Glass fiber mesh layer, fiber diameter 28-32μm, mesh count 38-42;

[0014] The polyurethane resin layer, with a thickness of 0.09-0.11 mm, contains 39-41% silane coupling agent KH-550 modified nano-silica with a particle size of 45-55 nm.

[0015] Furthermore, the wood substrate layer undergoes:

[0016] (1) Microwave drying: power density 1.5-1.8 W / cm³ 3 Process for 20-25 minutes;

[0017] (2) Vacuum drying: vacuum degree -0.07~-0.06MPa, 55-58℃ for 35-38min;

[0018] (3) Hot air circulation: 70-85℃, wind speed 3.2-3.8m / s.

[0019] Furthermore, the nano-silicone resin coating is subjected to:

[0020] Electrostatic spraying: voltage 42-48kV, distance 270-280mm;

[0021] Segmented curing: Preheat at 50-55℃ for 12-14 minutes, then cure at 95-98℃ for 26-28 minutes.

[0022] Furthermore, the melamine-impregnated paper layer is subjected to gradient hot pressing:

[0023] First stage: Hold pressure at 125-128℃ / 5.2-5.8MPa for 9-11 minutes;

[0024] Second stage: Hold pressure at 155-158℃ / 8.2-8.8MPa for 12-14 minutes.

[0025] Furthermore, the glass fiber mesh layer is treated with argon plasma: power 1100-1150W, gas flow rate 22-24L / min, treatment time 75-85s; coating 6-8g / m 2 Silane coupling agent KH-550.

[0026] Furthermore, the polyurethane resin layer is cured by gradient ultraviolet light, wherein:

[0027] 365nm wavelength 420-480mJ / cm 2 Irradiation time: 16-19 seconds;

[0028] 254nm wavelength 720-780mJ / cm 2 Irradiation for 9-11 seconds.

[0029] A manufacturing process for preparing moisture-proof and deformation-resistant melamine decorative panels includes the following steps:

[0030] (1) The wood substrate is subjected to microwave drying, vacuum drying and hot air circulation treatment in sequence;

[0031] (2) Apply a nano-silicone resin coating by electrostatic spraying and then cure it;

[0032] (3) The melamine-impregnated paper layer is laminated to the substrate using a gradient hot-pressing process;

[0033] (4) The glass fiber mesh layer is subjected to plasma treatment and coated with silane coupling agent KH-550;

[0034] (5) A polyurethane resin layer is formed by a gradient ultraviolet curing process.

[0035] Furthermore, the gradient hot pressing process in step (3) includes two stages, and vibration is applied during the hot pressing process. The vibration frequency is 95-105Hz and the amplitude is 0.34-0.36mm.

[0036] Furthermore, in step (4), the coating amount of the silane coupling agent is 6-8 g / m. 2 .

[0037] Furthermore, after the gradient ultraviolet curing in step (5) is completed, infrared auxiliary treatment is performed with an infrared wavelength of 3.5-4.5 μm and a power density of 0.9-1.1 W / cm². 2 The processing time is 6-7 minutes.

[0038] The beneficial effects of this invention are as follows:

[0039] 1. Significantly Enhanced Moisture Resistance. This decorative board effectively blocks moisture intrusion through precise control of the moisture content and density of the wood substrate layer and the rational use of phosphate-modified nano-alumina particles in the nano-silicone resin coating. After being placed in an environment with 90% relative humidity for 72 hours, the water absorption rate is only 3-5%, far lower than the 10-15% water absorption rate of traditional melamine decorative boards. This greatly enhances its moisture resistance, allowing it to maintain good performance in humid environments and reducing problems such as expansion and deformation caused by moisture.

[0040] 2. Significantly Enhanced Resistance to Deformation. The specific fiber diameter and mesh count of the glass fiber mesh layer, combined with the synergistic effect of the silane coupling agent KH-550 modified nano-silica in the polyurethane resin layer, form a stable supporting structure within the board and improve surface mechanical properties. After 50 cycles in a temperature range of -20℃ to 60℃, the dimensional change rate is only 0.1-0.3%, compared to the 0.5-1% change rate of traditional decorative panels, demonstrating superior resistance to deformation and ensuring that the board maintains a stable shape and size under conditions of temperature changes.

[0041] 3. Effectively improves interlayer bonding strength. Targeted treatment processes are applied to each layer, such as argon plasma treatment of the fiberglass mesh layer and coating with silane coupling agents, to promote interlayer chemical reactions and enhance chemical bonding. Interlayer peel strength tests show that this decorative panel achieves an interlayer peel strength of 5-7 N / mm, higher than the 3-5 N / mm of traditional decorative panels, effectively preventing delamination during use and significantly extending the service life of the decorative panel.

[0042] 4. Comprehensive optimization of coating and processing effects. From the electrostatic spraying and segmented curing of the nano-silicone resin coating, to the gradient hot pressing of the melamine-impregnated paper layer, and then to the gradient ultraviolet curing and infrared-assisted treatment of the polyurethane resin layer, each layer's processing technology is precisely controlled, comprehensively improving the performance of the board. The nano-silicone resin coating has an abrasion resistance of 5000-6000 cycles, higher than the 3000-4000 cycles of traditional coatings; the hardness of the polyurethane resin layer is 10-20% higher than that of traditional processes, while the melamine-impregnated paper layer has a stronger bond, improving the overall abrasion resistance, hardness, and appearance quality of the decorative board. Attached Figure Description

[0043] Figure 1 A schematic diagram of the structure of a moisture-proof and deformation-resistant melamine decorative panel.

[0044] Figure 2 For the examples and comparative examples, the performance (peel strength (N / mm)) is as follows: 2 A line graph comparing abrasion resistance (number of revolutions) and moisture resistance deformation rate (%). Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0046] Example 1

[0047] 1. Wood substrate treatment

[0048] Microwave drying: Select a wood-based substrate and place it inside a microwave drying device. Set the power density to 1.65 W / cm³. 3 At this power density, it can effectively promote the vibration of water molecules inside the wood, accelerate moisture evaporation, and avoid excessive damage to the wood structure. Continuous treatment for 23 minutes initially reduces the moisture content of the wood.

[0049] Vacuum drying: The microwave-dried wood is transferred to a vacuum drying device. The vacuum level is set to -0.063 MPa, the temperature to 57°C, and the treatment time is 36 minutes. Under these vacuum and temperature conditions, the boiling point of water decreases, which removes residual moisture from the wood, precisely controls the moisture content, and ensures that the moisture content of the wood substrate meets the requirements.

[0050] Hot air circulation: The vacuum-dried wood is placed in a hot air circulation oven, set at 75℃ and with an air velocity of 3.6 m / s. Through hot air circulation, the moisture distribution inside and on the surface of the wood is made uniform, and the treatment continues until the moisture content reaches 7.2%. At this point, the moisture content of the wood substrate is ≤8%, and the density is 800-850 kg / m³. 3 This provides a foundation for subsequent composite layers.

[0051] 2. Nano silicone resin coating

[0052] Electrostatic spraying: Prepare the nano-silicone resin coating and use the electrostatic spraying process. Set the spray gun voltage to 45kV and maintain a distance of 275mm between the spray gun and the surface of the wood substrate. Under these parameters, the coating particles are uniformly adsorbed onto the surface of the wood substrate under electrostatic action, forming a coating with a thickness of 0.20mm. This thickness, within the range of 0.18-0.22mm, can effectively exert the protective performance of the nano-silicone resin coating.

[0053] Segmented Curing: After spraying, the substrate enters the curing stage, first preheating at 53℃ for 13 minutes. Low-temperature preheating helps the solvent in the coating to evaporate slowly, allowing the coating to initially form a stable structure. The temperature is then raised to 97℃ and cured for 27 minutes. This high-temperature stage promotes full cross-linking of the resin in the coating, forming a nano-silicone resin coating. This coating contains 15-17% phosphate-modified nano-alumina particles with a particle size of 65-75 nm. These particles are uniformly dispersed in the coating, enhancing its waterproof and abrasion-resistant properties.

[0054] 3. Melamine-impregnated paper hot pressing

[0055] Stage 1: Melamine-impregnated paper and the board coated with nano-silicone resin are placed together in a hot press. The temperature is set at 126℃, the pressure at 5.5MPa, and the pressure is maintained for 10 minutes, while vibration at a frequency of 100Hz and an amplitude of 0.35mm is applied simultaneously. In this stage, the relatively low temperature and pressure allow the impregnated paper to initially adhere to the coating, and the vibration effectively removes air, improving the tightness of the bond.

[0056] Second stage: After the first stage, the temperature is increased to 157℃ and the pressure to 8.5MPa, and the pressure is maintained for 13 minutes. The higher temperature and pressure promote the full melting and penetration of the melamine-impregnated paper, which then firmly bonds with the coating to form a stable structure.

[0057] 4. Fiberglass mesh treatment

[0058] Argon plasma treatment: The glass fiber mesh was placed in an argon plasma treatment device with a power of 1130W and an argon gas flow rate of 23L / min for 80 seconds. Under the action of plasma, the molecular structure of the glass fiber mesh surface changed, generating a large number of active groups, which created conditions for subsequent coating with silane coupling agent.

[0059] Coating with silane coupling agent KH-550: Immediately after plasma treatment, 7 g / m² of the agent is coated onto the glass fiber mesh. 2 The silane coupling agent KH-550. Silane coupling agents can chemically react with the surface-active groups of the glass fiber mesh and the subsequent polyurethane resin layer, enhancing interlayer adhesion.

[0060] 5. Curing of polyurethane resin

[0061] Gradient UV curing: After laminating the glass fiber mesh coated with silane coupling agent to the board, gradient UV curing is performed. First, ultraviolet light with a wavelength of 365nm is used, and the irradiation energy is set to 450mJ / cm². 2The irradiation time was 17 seconds. This wavelength of ultraviolet light initiated a partial photochemical reaction in the polyurethane resin, causing initial curing. Subsequently, ultraviolet light with a wavelength of 254 nm and an irradiation energy of 750 mJ / cm² was used. 2 Irradiation for 10 seconds. This wavelength of ultraviolet light further promotes the cross-linking reaction of the resin, allowing the polyurethane resin to fully cure.

[0062] Post-curing infrared-assisted treatment: After ultraviolet curing, infrared-assisted curing is used. The wavelength is set to 4.0 μm and the power density to 1.0 W / cm². 2 The process lasts 6.5 minutes. Infrared radiation penetrates deep into the material, causing the molecules inside the polyurethane resin to react further, eliminating stress, improving the uniformity and stability of the coating, and ultimately forming a polyurethane resin layer with a thickness of 0.09-0.11 mm, containing 39-41% silane coupling agent KH-550 modified nano-silica, and a particle size of 45-55 nm.

[0063] Example 2

[0064] Wood substrate: The density of the wood substrate is 800 kg / m³ 3 After drying, the moisture content is 7.8%.

[0065] Microwave drying: power density set to 1.6 W / cm³ 3 Processing time: 22 minutes.

[0066] Vacuum drying: Vacuum degree set to -0.065MPa, temperature at 56℃, treatment for 36min.

[0067] Gradient hot pressing: The first stage temperature is 125℃, the pressure is 5.4MPa, and the pressure is held for 9 minutes.

[0068] Argon plasma treatment: power 1100W, gas flow rate 22L / min, treatment time 75s.

[0069] Gradient UV curing: 365nm wavelength UV irradiation energy is 420mJ / cm² 2 Irradiation time: 16 seconds.

[0070] The above are the adjustments to the key parameters; other parameters are the same as in Example 1.

[0071] Example 3

[0072] Wood substrate: The density of the wood substrate is increased to 850 kg / m³ 3 The moisture content decreased to 7.1%.

[0073] Microwave drying: Power density increased to 1.7 W / cm³ 3 Processing time: 24 minutes.

[0074] Vacuum drying: The vacuum degree was adjusted to -0.055MPa, the temperature was 57℃, and the treatment time was 37min.

[0075] Gradient hot pressing: In the second stage, the temperature is increased to 158℃ and the pressure is increased to 8.8MPa, and the pressure is maintained for 14 minutes.

[0076] Argon plasma treatment: power increased to 1150W, gas flow rate 24L / min, treatment time 85s.

[0077] Gradient UV curing: 254nm wavelength UV irradiation energy is 780mJ / cm² 2 Irradiation time: 11 seconds.

[0078] The above are the adjustments to the key parameters; other parameters are the same as in Example 1.

[0079] Comparative Example 1

[0080] This comparative example omits the vacuum drying step and only performs microwave drying (power density 1.65 W / cm³). 3 The process was carried out for 23 minutes with hot air circulation (temperature 75℃, wind speed 3.6m / s), and the other parameters were the same as in Example 1.

[0081] 2. Test Results

[0082] Moisture content (%): 7.2 in Example 1 and 9.3 in Comparative Example 1. The higher moisture content indicates the absence of a vacuum drying step, resulting in insufficient removal of moisture from the wood and increasing the risk of the boards becoming damp.

[0083] Heat distortion rate (%): 0.08 for Example 1 and 0.42 for Comparative Example 1. The higher heat distortion rate in Comparative Example 1 indicates that the higher moisture content reduces the dimensional stability of the sheet material, making it more prone to deformation with temperature changes.

[0084] Peel strength (N / mm) 2 (Note: Example 1 had a peel strength of 12.5, and Comparative Example 1 had a peel strength of 7.9.) The lower peel strength indicates that changes in moisture content affect the interlayer bonding strength, leading to a decrease in overall performance.

[0085] Comparative Example 2

[0086] The comparative example removes the gradient hot pressing and replaces it with single-stage hot pressing: 157℃ / 8.5MPa holding pressure for 23min. The remaining parameters are the same as in Example 1.

[0087] 2. Test Results

[0088] Color difference ΔE of impregnated paper: 0.8 in Example 1, and as high as 3.6 in Comparative Example 2. The large color difference indicates that the single-stage hot pressing causes uneven heating of the impregnated paper, affecting color consistency.

[0089] Abrasion resistance (revolutions): 4200 for Example 1 and only 2650 for Comparative Example 2. The lower abrasion resistance revolutions indicate that single-stage hot pressing cannot fully bond the melamine-impregnated paper to the coating, thus reducing the product's abrasion resistance.

[0090] Hot-press delamination risk: No delamination was observed in Example 1, while significant delamination was observed in Comparative Example 2. This indicates that single-stage hot pressing is not conducive to forming a strong bond between layers, increasing the risk of hot-press delamination.

[0091] Comparative Example 3

[0092] This comparative example omits the argon plasma treatment step and directly coats the sample with a silane coupling agent (7g / m³). 2 The remaining parameters are the same as in Example 1.

[0093] 2. Test Results

[0094] Silane coating uniformity (%): 98.5 in Example 1 and only 82.3 in Comparative Example 3. The lower uniformity indicates the lack of argon plasma treatment, resulting in uneven distribution of the silane coupling agent on the surface of the glass fiber mesh, which affects the stability of interlayer bonding.

[0095] Moisture and heat resistance test (48h): Example 1 showed no delamination, while Comparative Example 3 showed delamination. This indicates that the reduced uniformity of the silane coating and insufficient interlayer adhesion resulted in poor performance of Comparative Example 3 in the moisture and heat resistance test.

[0096] Adhesion after UV aging: Example 1 showed no decrease, while Comparative Example 3 showed a 35% decrease. This indicates that without argon plasma treatment, the adhesion between the fiberglass mesh and the polyurethane resin layer significantly decreased after UV aging, affecting product durability.

[0097] As can be seen from the above embodiments and comparative examples, the reasonable setting of each process step and parameter in this invention has a significant impact on the performance of the moisture-proof and deformation-resistant melamine decorative board. Strict adherence to the technical features in the claims results in products with excellent performance in terms of moisture content control, peel strength, abrasion resistance, and resistance to moisture deformation. However, the absence of key steps or unreasonable parameter adjustments will lead to a decline in product performance.

[0098] Table 1 Comparison of Data Between Examples and Comparative Examples

[0099]

[0100] See the schematic diagram of the moisture-proof and deformation-resistant melamine decorative panel structure. Figure 1 Examples and comparative performance (peel strength (N / mm)) 2 A line graph comparing abrasion resistance (revolutions) and moisture deformation rate (%) is shown below. Figure 2 .

[0101] The above description is merely a preferred embodiment of the present invention; however, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concepts, should be covered within the scope of protection of the present invention.

Claims

1. A production process for moisture-proof and deformation-resistant melamine decorative panels, characterized in that: The production process of the moisture-proof and deformation-resistant melamine decorative board is characterized by including the following steps: (1) The wood substrate is subjected to microwave drying, vacuum drying and hot air circulation treatment in sequence; (2) Apply a nano-silicone resin coating by electrostatic spraying and then cure it; (3) The melamine-impregnated paper layer is laminated to the substrate using a gradient hot pressing process; the gradient hot pressing process includes two stages, and vibration is applied during the hot pressing process with a vibration frequency of 95-105Hz and an amplitude of 0.34-0.36mm; (4) The glass fiber mesh layer is subjected to plasma treatment and coated with silane coupling agent KH-550; the coating amount of silane coupling agent is 6-8 g / m². (5) A polyurethane resin layer is formed by a gradient ultraviolet curing process; The moisture-proof and deformation-resistant melamine decorative board comprises, from bottom to top, a wood substrate layer, a nano-silicone resin coating, a melamine-impregnated paper layer, a fiberglass mesh layer, and a polyurethane resin layer. Wood substrate layer, moisture content ≤8%, density 800-850kg / m³; The nano-silicone resin coating has a thickness of 0.18-0.22 mm and contains 15-17% phosphate-modified nano-alumina particles with a particle size of 65-75 nm. Glass fiber mesh layer, fiber diameter 28-32μm, mesh count 38-42; The polyurethane resin layer has a thickness of 0.09-0.11 mm and contains 39-41% silane coupling agent KH-550 modified nano-silica with a particle size of 45-55 nm.

2. The production process of the moisture-proof and deformation-resistant melamine decorative board according to claim 1, characterized in that, Wood substrate layer: (1) Microwave drying: power density 1.5-1.8W / cm³ for 20-25min; (2) Vacuum drying: vacuum degree -0.07~-0.06MPa, 55-58℃ for 35-38min; (3) Hot air circulation: 70-85℃, wind speed 3.2-3.8m / s.

3. The production process of the moisture-proof and deformation-resistant melamine decorative board according to claim 1, characterized in that, Nano-silicone resin coating is applied as follows: Electrostatic spraying: voltage 42-48kV, distance 270-280mm; Segmented curing: Preheat at 50-55℃ for 12-14 minutes, then cure at 95-98℃ for 26-28 minutes.

4. The production process of the moisture-proof and deformation-resistant melamine decorative board according to claim 1, characterized in that, Melamine-impregnated paper layer is subjected to gradient hot pressing: First stage: Hold pressure at 125-128℃ / 5.2-5.8MPa for 9-11 minutes; Second stage: Hold pressure at 155-158℃ / 8.2-8.8MPa for 12-14 minutes.

5. The production process of the moisture-proof and deformation-resistant melamine decorative board according to claim 1, characterized in that, The fiberglass mesh layer is treated with argon plasma: power 1100-1150W, gas flow rate 22-24L / min, treatment time 75-85s; Coating with silane coupling agent KH-550.

6. The production process of the moisture-proof and deformation-resistant melamine decorative board according to claim 1, characterized in that, The polyurethane resin layer is cured by gradient ultraviolet light, wherein: Irradiation at 365nm wavelength for 420-480mJ / cm² for 16-19s; Irradiation at 254nm wavelength for 720-780mJ / cm² for 9-11s.

7. The production process of the moisture-proof and deformation-resistant melamine decorative board according to claim 1, characterized in that, After the gradient ultraviolet curing in step (5) is completed, infrared auxiliary treatment is carried out. The infrared wavelength is 3.5-4.5μm, the power density is 0.9-1.1W / cm², and the treatment time is 6-7min.

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