Manufacturing method of embossed technical wood

Abstract

The invention relates to an embossed technical wood manufacturing method which specifically comprises the following steps: preparing raw materials, preparing a softening solution A containing ammonia water and other components, sanding a technical wood base material, and coating a primer; a technical wood veneer laminated board B is prepared, and technical wood veneers and the gluing base material are subjected to hot pressing through a polyurethane adhesive; a pretreated laminated board C is prepared, softening liquid A is sprayed to the laminated board B, and the water content of the veneer is controlled; preparing an engineered wood embossed board, and embossing the pretreated laminated board C; and finished product processing: cutting, trimming, grinding and polishing the embossed plate. The invention provides a novel softening liquid formula and a novel treatment process, optimizes a polyurethane primer and adhesive formula, strictly sets operation conditions of each step, and performs specific process parameter control. Through the measures, the problems of an existing embossing process are effectively solved, the embossing stability and quality are improved, the visual effect and the additional value of a product are improved, and the requirement of the market for high-quality embossed technical wood is met.

Description

Technical Field

[0001] The invention relates to a method for producing embossed technical wood, in particular to a method for producing embossed technical wood, and provides a method for improving the embossing stability of technical wood veneer panels. Background Art

[0002] Technology wood is a decorative wood that is made from artificial fast-growing wood, through a series of processes such as bleaching and dyeing, and then planed. At present, technology wood is widely used in the field of interior decoration, especially in the market that pursues three-dimensional decorative effects, the demand for 3D technology wood continues to rise. 3D technology wood is based on flat technology wood materials and is made by applying carving or embossing technology. Among them, although the carving process can produce fine patterns, its slow speed and high cost limit its wide application. In contrast, the embossing process uses steel plates or steel rollers engraved with different patterns to press out three-dimensional patterns on the surface of technology wood. The production process is simple, which not only improves the decorative effect and texture of ordinary technology wood, but also reduces production costs.

[0003] However, there are some problems with the existing embossing process. At present, the embossing process is mainly divided into two types: room temperature embossing and high temperature embossing. Although room temperature embossing is simple to operate, it has low efficiency and poor embossing effect. In addition, the elasticity of the wood after embossing will cause the embossed pattern surface to rebound easily. Although the high-temperature embossing process can make the pattern depth meet the design requirements, there is also the problem of elastic deformation of the pattern. In addition, during the embossing process of the technical wood veneer panel, the wood is easily damaged and cracked due to the influence of high temperature and pressure, which is also an important factor affecting the effect of the embossing process. Summary of the invention

[0004] The purpose of the present invention is to provide a method for embossing technological wood with simple operation and good stability, so as to solve the problems existing in the existing embossing process.

[0005] By softening the technical wood veneer to improve its plasticity, reducing the temperature and pressure of hot pressing embossing, the possibility of deformation and cracking of the substrate due to excessive hot pressing pressure is reduced on the basis of improving the embossing depth and embossing effect. The embossing technology proposed by the present invention not only greatly improves the embossing depth and effect of embossed technical wood, but also ensures the stability of the entire embossing process, and improves the overall production efficiency and output.

[0006] The softening formula and treatment process provided by the present invention significantly enhance the embossing effect of the technological veneer, making the embossed pattern more profound and three-dimensional, thereby greatly improving the visual effect and added value of the product.

[0007] The purpose of spraying softener is to make the surface technology veneer obtain a temporary plastic state, which can significantly reduce the elastic modulus of wood, making the wood softer. When the moisture content of wood is between 20% and 30%, the strength of wood will reach its lowest point, and the elasticity of wood will be greatly reduced, so that wood can produce greater deformation. Embossing operation under this moisture content condition can maximize the embossing effect, making the final embossed pattern clearer and more beautiful, while also better maintaining the stability and durability of wood.

[0008] During the embossing process, precise control of parameters such as temperature, pressure and time is the key to ensuring the stability of the finished product quality. The present invention effectively avoids finished product defects caused by improper operation, such as blistering, deformation or blurred texture, by strictly setting the operating conditions of each step, such as the moisture content of the veneer, hot pressing parameters, and the temperature and pressure of the embossing machine, thereby ensuring the overall stability and consistency of the embossed technical wood.

[0009] When embossing in the embossing machine, the temperature and pressure parameters used in the present invention are accurately calculated and optimized to ensure that the best embossing effect is achieved without damaging the wood. The temperature is controlled within the range of 60-80°C, which can effectively soften the wood while avoiding burning or deformation of the wood due to excessive temperature. The pressure is controlled within the range of 6-12MPa, which can ensure that the wood can be fully shaped during the embossing process while avoiding damage to the wood due to excessive pressure.

[0010] The present invention provides a method for producing embossed technical wood, which specifically comprises: S1 prepare raw materials: prepare softening liquid A by weight percentage by mixing 20-50 parts of ammonia water, 10-30 parts of polyethylene glycol, 1-3 parts of sodium dodecylbenzene sulfonate, 15-40 parts of water, and 2-8 parts of nanocellulose; process the technical wood substrate; S2: preparing the technological veneer veneer panel B: placing the processed substrate into a glue coating machine, applying glue with a rubber roller, and applying the adhesive in an amount of 60-120 g / m²; placing the technological veneer on the glued substrate, and putting it into a hot press for hot pressing, the pressure applied by the hot press is 10-16 MPa, the temperature is 100-120° C., and the time is 3-8 minutes, to obtain the technological veneer veneer panel B; S3 Preparation of pre-treated veneer board C: Clean the surface of the technical veneer veneer board B, spray softening liquid A, dry it naturally for 2-6 hours, and control the moisture content of the surface technical veneer to be 20-30%, so as to obtain the pre-treated veneer board C; S4 Preparation of technological wood embossed board: Put the pretreated veneer board C into an embossing machine for embossing at a temperature of 60-80°C and a pressure of 6-12MPa to obtain a technological wood embossed board; S5 Finished product processing: cutting, trimming, grinding and polishing the technological wood embossed board to obtain the finished embossed technological wood.

[0011] The method for making embossed technical wood provided by the present invention has innovated the softening treatment process, and uses a unique formula to configure a softening liquid A containing ammonia water, polyethylene glycol, sodium dodecylbenzene sulfonate, water and nanocellulose, and at the same time, the proportion of each component in the softening liquid A is carefully designed and strictly controlled. This combination is relatively rare in the prior art, and the effective softening of technical wood veneer is achieved through the synergistic effect of each component. Sodium dodecylbenzene sulfonate, as a surfactant, reduces the surface tension of the veneer and improves the penetration effect of the softener; polyethylene glycol maintains moisture balance and prevents water loss; ammonia water swells, promotes the expansion of wood fibers, and improves plasticity; nanocellulose enhances the structural stability of the wood. Ammonia, as a main softening agent, can enter the cellulose crystallization area of ​​the wood, and the difference in the physical properties of the wood before and after the treatment is small, the cost is low and it is easy to control. The concentration of ammonia water is strictly controlled within the mass fraction range of 20-30%, ensuring that the wood will not be excessively corroded or damaged while softening the wood.

[0012] Preferably, the step S1 of preparing raw materials comprises the following specific steps: S11: prepare softening liquid A: mix 40-50 parts of 20-30% ammonia water, 18-22 parts of polyethylene glycol, 1-2 parts of sodium dodecylbenzene sulfonate, 30-40 parts of water, and 2-5 parts of nanocellulose according to weight percentage; S12 substrate processing: Select a pressed, dyed and modified technological wood substrate with a thickness of 3-18mm. Perform preliminary sanding on the surface of the technological wood substrate to remove impurities and surface unevenness, and evenly apply a layer of primer on the sanded surface.

[0013] Sanding is mainly used to treat the surface of high-tech wood substrates. The smoothing operation can effectively remove uneven surfaces and impurities, improve surface flatness, make subsequent processing more precise, and avoid decorative problems caused by surface defects. Moreover, sanding can increase the roughness of the wood surface, exposing more microscopic pores and active sites in the wood, providing good conditions for the adhesion of the primer and significantly enhancing the adhesion between the primer and the substrate.

[0014] Applying primer is to form a protective film on the surface of the substrate after sanding. This film can protect the wood from the damage of external environmental factors such as moisture, oxygen and chemicals, effectively prevent the wood from decaying, oxidizing and being chemically corroded, and extend the service life of the high-tech wood; at the same time, the primer can adjust the color and gloss of the wood, fill in tiny pores to improve the surface flatness and texture, and enhance the decorative effect; and, as an intermediate layer, the primer can also provide a good adhesion foundation for the topcoat, ensuring the stability and durability of the entire coating system.

[0015] Multilayer boards and blockboards have low hygroscopic expansion rates and high surface flatness, which are conducive to the uniform display of embossed patterns. Multilayer boards and blockboards are selected as substrates, and they also take into account their good stability and strength, and can withstand the pressure and temperature changes during the embossing process. In the selection of raw materials for the substrate, one of poplar, birch, and pine is selected. These tree species have good processing performance and relatively low cost, clear texture, easy embossing, and moderate wood strength. It will not affect the structural stability of the final product due to excessive softening, and is suitable as a substrate tree species.

[0016] Preferably, the substrate in step S1 is one of multilayer board and blockboard, and the raw material is one of poplar, birch and pine; the thickness of multilayer board as the technical wood substrate is 3-18 mm, and the thickness of blockboard as the technical wood substrate is 12-18 mm; The primer is an environmentally friendly polyurethane paint, and its formula includes: 30-50 parts of vegetable oil-based polyol, 20-30 parts of polyether polyol, 20-30 parts of aliphatic isocyanate, 1-3 parts of nano titanium dioxide, 0.2-0.5 parts of ultraviolet absorber, 0.3-0.8 parts of antioxidant, and 0.1-0.3 parts of nano silver.

[0017] The present invention improves the performance of the primer by optimizing the formula and process of the polyurethane paint, and reduces the components that may produce harmful volatiles in the formula design. The mutual coordination of the components in the primer formula makes the product quality more stable during the production process. The primer used for substrate processing must be able to firmly adhere to the surface of the technical wood substrate, which requires the primer to have a suitable viscosity and surface tension, and can fully infiltrate the pores and microstructures on the surface of the wood to form chemical bonds or physical adsorption, ensuring that it will not fall off easily during subsequent processing and use; at the same time, the primer used also needs to have good filling ability, which can fill the tiny pores, scratches and uneven places on the surface of the technical wood substrate, making the surface more flat and smooth, which is very important for improving the quality and overall effect of the subsequent gluing process. Therefore, whether it is the selection of raw materials or the proportion of each component, it is necessary to go through multiple designs and tests to ensure that each batch of primer products can have consistent performance and quality, providing reliable protection for the large-scale production of technical wood products. In the primer formula provided in the process of the present invention, the vegetable oil-based polyol is derived from vegetable oils such as soybean oil and linseed oil through chemical modification, which provides flexibility and good adhesion for the polyurethane paint, and has environmental protection characteristics, reducing the dependence on petrochemical resources; the polyether polyol is matched with the vegetable oil-based polyol to provide the hardness and wear resistance and other properties required by the polyurethane paint; the aliphatic isocyanate has good weather resistance and low yellowing tendency, is suitable for use as a primer, reacts with the polyol to form a polyurethane network structure, and provides the basic properties of the coating; nano-titanium dioxide enhances the hardness, wear resistance and self-cleaning ability of the primer, has a photocatalytic effect under light conditions, and can decompose harmful gases; the ultraviolet absorber protects the primer from damage by ultraviolet rays, prolongs its service life, and prevents the coating from fading, cracking and other problems; the antioxidant resists oxidation and improves the stability of the primer, especially during long-term use; nano-silver is used as an antibacterial agent to enhance the antibacterial property of the primer and prevent bacteria and mold from growing on the surface of the technical wood.

[0018] The present invention innovates the primer spraying process and adopts electrostatic spraying technology to coat an environmentally friendly polyurethane paint primer. Electrostatic spraying can make the paint droplets uniformly adsorbed on the surface of the substrate under the action of the electric field, thereby improving the uniformity and efficiency of the coating. Compared with the traditional spraying method, electrostatic spraying can reduce the generation of paint mist, reduce environmental pollution, and at the same time improve the utilization rate of the primer, reduce the waste of the coating, and save costs. The electrostatic spraying technology is adopted for construction, and under the conditions of specific temperature, relative humidity, spraying voltage, spraying current and spraying distance, the primer can be uniformly attached to the surface of the technological wood substrate. This precisely controlled construction condition can ensure that the coating quality of the primer is more stable, and the primer thickness on the wood surface is uniform, which is conducive to the subsequent process, and can better play the protective and decorative functions of the primer.

[0019] The primer construction environment should be kept clean, dry and well ventilated, with a construction temperature of 10-35°C and a relative humidity of 40-80%. Temperature and humidity have a great impact on the drying speed and quality of the primer. In a high humidity environment, the primer will turn white and bubble; in a low temperature environment, the drying speed of the primer will be significantly slowed down, extending the production cycle and reducing production efficiency. Improper spraying pressure and distance will cause sagging or paint mist rebound.

[0020] In electrostatic spraying technology, spraying voltage is a key parameter. Higher voltage will make the paint particles carry more charge, thereby enhancing its adsorption in the electrostatic field. When the voltage is between 30-80kV, the paint particles in the primer can be fully charged, so that the paint can be more evenly covered on the wood, including some hard-to-reach corners and gaps. The appropriate spraying voltage helps to control the thickness and uniformity of the coating. If the voltage is too low, the paint particles are not charged enough, resulting in uneven coating, and local thin or thick coating. Excessive voltage will cause excessive atomization of the paint, resulting in too fine paint particles, which will float in the air, resulting in waste of paint, and affecting the working environment and the health of operators. By controlling the voltage within the range of 30-80kV, the primer can be uniformly deposited on the surface of the technical wood substrate, improving the coating quality and ensuring the appearance and performance of the product. If the spraying voltage is too high and exceeds a certain critical value, a discharge phenomenon will occur between the spray gun and the substrate, threatening the safety of the operator, while causing abnormal deposition of the paint, forming an uneven coating, and even damaging the surface of the substrate. Therefore, controlling the voltage within the specified range can effectively avoid such potential safety hazards and quality problems.

[0021] The spraying current is closely related to the flow rate of the paint, and the magnitude of the current directly affects the speed and flow rate of the paint sprayed out by the spray gun. Within a certain range, the greater the current, the greater the flow rate of the paint, and the thicker the coating will be. By accurately controlling the spraying current at 0.1-0.5A, the thickness of the primer coating can be adjusted according to the specific requirements of the technological wood products. Maintaining the stability of the spraying current is essential to ensure the stability of the coating quality. Large fluctuations in the spraying current will lead to unstable paint flow, which in turn makes the thickness of the coating uneven, forming a situation of local thick and local thin on the surface of the technological wood, affecting the appearance and performance of the product. Reasonable control of the spraying current can also help save energy and reduce paint waste. A lower spraying current means that the amount of paint used can be effectively controlled to avoid unnecessary paint consumption, which can not only reduce production costs, but also reduce the generation of paint waste, in line with environmental protection requirements. At the same time, a lower current can also help reduce the energy consumption of equipment and improve production efficiency.

[0022] Preferably, the primer construction method in step S12 adopts electrostatic spraying technology to apply environmentally friendly polyurethane paint primer, with a temperature of 10-35°C, a relative humidity of 40-80%, a spraying voltage of 30-80kV, a spraying current of 0.1-0.5A, and a spraying distance of 15-30cm.

[0023] The thickness selection, drying, insect-proofing, anti-corrosion treatment and surface smoothness and durability of high-tech veneer are of great significance. Appropriate thickness facilitates lamination and hot pressing operations, which is conducive to cost control; drying treatment can control moisture content, prevent mildew and decay, and ensure stable quality; insect-proof treatment can improve product durability and meet usage requirements; anti-corrosion treatment can resist chemical erosion, adapt to complex environments, and extend service life; it can ensure tight lamination, improve appearance quality and ensure long-term performance.

[0024] The thickness of high-tech veneer is in the range of 0.5-3.0mm, which makes the veneer neither too thin and fragile during handling, gluing and laminating, nor too thick and difficult to combine well with the base material during hot pressing or require higher equipment requirements and energy consumption, which brings great convenience to the processing process; at the same time, this thickness range can reasonably utilize raw materials while meeting product quality, avoiding the increase in processing costs due to too thinness or the waste of raw materials due to too thickness.

[0025] The key to the drying process is to effectively control the moisture content of the veneer. In the subsequent hot pressing process of bonding with the substrate, it can avoid the dilution of the adhesive due to excessive moisture content, thereby ensuring the bonding strength. Moreover, in the long-term use process, it can prevent deformation and warping caused by water evaporation, while reducing the conditions for mold growth, reducing the possibility of discoloration and mildew of the veneer, and ensuring the stability and durability of product quality.

[0026] Insect-proof treatment is an important part of quality assurance for technological veneer. It can effectively resist the erosion of veneer by insects. Whether in storage, processing or use, it can prevent pests from damaging the veneer structure. It is essential to extend the service life of the product and ensure product integrity and aesthetics. It can especially meet the application scenarios that require insect-proof performance, such as furniture manufacturing and interior decoration, and provide users with high-quality products without hidden dangers of pests.

[0027] The technological veneer after anti-corrosion treatment has excellent resistance to external erosion. In complex environments such as outdoors or indoors with high humidity, it can delay the decay process of wood, ensure the integrity of the product's structure and appearance during long-term use, reduce the frequency of maintenance and replacement, and effectively reduce the cost of use.

[0028] The smooth and durable surface of technological veneer has dual value. From the perspective of bonding, the flat surface can be in close contact with the base material, avoiding problems such as hollowing and gaps after bonding, ensuring product quality while improving the visual appearance of the product. In terms of long-term performance, the surface durability enables the veneer to remain in good condition despite wear and scratches caused by frequent wiping, placement and movement of objects in daily use, thereby maintaining the appearance and performance of the product throughout its service life.

[0029] Preferably, the technological veneer in step S2 has a thickness of 0.5-3.0 mm, is dried, and treated with insect and anti-corrosion treatments, and has a smooth and durable surface.

[0030] When selecting adhesives, the present invention preferably uses polyurethane adhesives with high bonding strength and good heat resistance. It can maintain good bonding strength in a wide temperature range and remain stable even in a humid or high temperature environment, ensuring that the veneer will not debond in a humid environment when spraying softeners and during hot pressing. The polyurethane adhesive also has good toughness and can adapt to the slight deformation of wood during the embossing process, thereby ensuring that the technical veneer is tightly bonded to the substrate and reducing the possibility of cracking and falling off.

[0031] Polyurethane adhesive has good bonding effect on various materials. It can react with active groups such as hydroxyl groups in wood to form chemical bonds. It can achieve good bonding on different types of substrates such as technical veneer, multilayer board and blockboard. When the amount of glue applied is 60-120g / m², the polyurethane adhesive used in the process of the present invention can ensure that the veneer and the substrate are tightly bonded. Whether it is different wood such as poplar, birch or pine, it can be effectively bonded and is not easy to delaminate after hot pressing. At the same time, it can also well adapt to the surface state of different roughness and moisture content of wood caused by processing, has good wettability, can fill the tiny pores on the surface of the wood, and closely contact the wood at the microscopic level, thereby enhancing the stability of bonding.

[0032] The adhesive used in the present invention has excellent flexibility and elasticity of the adhesive layer after curing. When the technological wood undergoes a slight deformation due to environmental factors or external forces, the adhesive layer can expand and contract without breaking, so that it can effectively avoid the problem of debonding under different environmental conditions and extend the service life of the product; at the same time, the adhesive layer can enhance the wear resistance and scratch resistance of the technological wood product, play a buffering and protective role, reduce damage to the wood surface, and keep the appearance intact.

[0033] Polyurethane adhesives have good tolerance when exposed to detergents, mild acid and alkali solutions and other chemical substances. When cleaning technical wood furniture, they will not become ineffective due to wiping with chemical detergents, and can maintain the bonding state between the veneer and the substrate. For technical wood products exposed to sunlight or in outdoor environments, it can resist the influence of ultraviolet rays, moisture and oxygen. Its chemical bonds can absorb and disperse ultraviolet energy, prevent the glue layer from aging and yellowing, and can also prevent moisture and oxygen penetration, reduce the possibility of moisture or oxidation failure of the glue layer, and extend the outdoor service life.

[0034] Compared with some traditional adhesives, the innovative polyurethane adhesive of the present invention releases fewer volatile organic compounds during the curing process, which helps reduce indoor air pollution, meets environmental protection requirements, and provides users with a healthier indoor environment.

[0035] Preferably, the adhesive in step S2 is a polyurethane adhesive, and the formula includes: 40-60 parts of polyester polyol, 20-40 parts of polyether polyol, 15-30 parts of toluene diisocyanate, 45-55 parts of diphenylmethane diisocyanate, 0.05-0.3 parts of dibutyltin dilaurate, 5-15 parts of 1,4-butanediol, 5-15 parts of dioctyl phthalate, 10-30 parts of calcium carbonate, 0.1-0.5 parts of benzotriazole ultraviolet absorber, and 0.1-1 parts of hindered phenol antioxidant.

[0036] The polyurethane adhesive formula involved in the present invention has innovative values ​​in terms of comprehensive performance, cross-linking structure optimization and adaptability to various application environments through the compounding of polyols, the mixing of isocyanates and the reasonable matching of additives.

[0037] The specific ratio of polyester polyol and polyether polyol in the formula is an innovative application. By using 40-60 parts of polyester polyol and 20-40 parts of polyether polyol, the good adhesion and strength characteristics of polyester polyol are combined with the flexibility and low temperature performance advantages of polyether polyol. This combination allows the adhesive to achieve a good balance between hardness and flexibility. Polyester polyol and polyether polyol are the main bonding components, reacting with isocyanate to form the main chain structure of polyurethane; polyester polyol can provide good hardness and chemical resistance, while polyether polyol gives the adhesive good flexibility and elasticity; the combination of these two polyols enables the adhesive to maintain a certain hardness after curing to ensure the firm bonding of the technical veneer and the substrate, and to have sufficient flexibility to adapt to the slight deformation of the wood in different environments. In the past, adhesives basically focused on one aspect. This formula uses a reasonable combination of two polyols to ensure that the technical veneer is firmly bonded to the substrate while effectively adapting to the deformation of the wood caused by environmental changes.

[0038] Toluene diisocyanate and diphenylmethane diisocyanate are key components that react with polyols. They have high reactivity and can react quickly with polyols to form a highly cross-linked polyurethane structure. This cross-linked structure enhances the cohesion and bonding strength of the adhesive, allowing the technical wood veneer to be firmly attached to the substrate during the hot pressing process and long-term use. Compared with traditional single-component isocyanate adhesives, this two-component design can give full play to the advantages of the two isocyanates, further enhance the cohesion of the adhesive, and enable the technical wood veneer to fit tightly to the substrate under various complex use conditions, providing a guarantee for the long-term stability of the technical wood.

[0039] As a catalyst, dibutyltin dilaurate can effectively adjust the reaction speed of adhesives. In the production process of adhesives, the control of reaction speed is very important. Under the conditions of pressure and temperature applied by the hot press, 0.05-0.3 parts of dibutyltin dilaurate can make the adhesive fully react within 3-8 minutes of hot pressing time, improve production efficiency, ensure that the reaction between isocyanate and polyol is completed within the appropriate time, and enable the adhesive to achieve the best bonding performance within the appropriate process time after coating.

[0040] 1,4-Butanediol and dioctyl phthalate as plasticizers can reduce the hardness of the adhesive and increase its flexibility and plasticity; help the adhesive to better fill the tiny pores on the surface of the wood and improve the fit with the wood; at the same time, it can also improve the processing properties of the adhesive, making it smoother and easier to operate during the gluing process.

[0041] As a filler, calcium carbonate can increase the volume of the adhesive and reduce costs; it can also improve the rheological properties of the adhesive and prevent the adhesive from settling or stratifying during storage and use; at the same time, it can also enhance the wear resistance and tear resistance of the adhesive and improve the mechanical properties of the adhesive.

[0042] 0.1-0.5 parts of benzotriazole UV absorbers can effectively absorb ultraviolet rays and prevent the adhesive from aging, yellowing and performance degradation when exposed to sunlight or outdoor environments for a long time. For high-tech wood products used outdoors or indoors in direct sunlight, it can maintain the bonding performance and appearance stability of the adhesive.

[0043] 0.1-1 part of hindered phenol antioxidant can prevent the components in the adhesive from reacting with oxygen in the air to produce oxidation, delay the aging process of the adhesive during the long-term use of high-tech wood products, extend its service life, and ensure that the bonding performance of the adhesive is not affected by oxidation.

[0044] Spraying softening liquid can improve the properties of wood. It can enhance the plasticity of wood, which is conducive to forming exquisite patterns during embossing. It can also control the moisture content of wood to keep it within an appropriate range to avoid brittle cracking, deformation or mold of wood. In terms of improving product quality, it can improve the quality and precision of embossing, make the embossed pattern clearer and more beautiful, and ensure product consistency. In terms of process connection, it can optimize subsequent processing procedures, reduce the requirements of embossing process on equipment and energy, make finished product processing easier to operate, and improve production efficiency.

[0045] Preferably, the spraying environment temperature of the softening liquid in step S3 is 15-30°C, the relative humidity is 40-60%, the spray gun pressure is controlled at 0.2-0.4MPa, the spraying amount per square meter of wood surface is 80-120g, a uniform and continuous multi-layer spraying method is adopted, the vertical distance between the spray gun and the wood surface is maintained at 20-30cm, and the interval between each layer of spraying is 10-15 minutes.

[0046] The spraying environment temperature of the softening liquid is 15-30℃, which is conducive to the good adhesion and penetration of the softening liquid on the wood surface. If the temperature is too low, the fluidity of the softening liquid will deteriorate and it will not be able to spread evenly on the wood surface, resulting in local accumulation or inability to fully contact the wood, affecting the softening effect; and if the temperature is too high, some components in the softening liquid will evaporate too quickly, changing the concentration and performance of the softening liquid, thereby affecting its softening effect on the wood, and failing to make the moisture content of the technical veneer reach the ideal range of 20-30%.

[0047] The relative humidity range for spraying the softening liquid is 40-60%. The moisture content in the air is neither too high to dilute the softening liquid, nor too low to cause the softening liquid to dry out too quickly. If the humidity is too high, the softening liquid will absorb too much moisture, affecting its component ratio and softening performance. If the humidity is too low, the softening liquid will dry out quickly after contacting the wood surface, unable to fully penetrate the wood, and cannot achieve uniform softening.

[0048] The spray gun pressure range is 0.2-0.4MPa, which can ensure that the softening liquid is sprayed onto the wood surface at an appropriate speed and droplet size; if the pressure is too low, the softening liquid will be sprayed slowly and the droplets will be large, resulting in uneven spraying and flowing, and it will be impossible to form a uniform and continuous coating; if the pressure is too high, the droplets will be too small and will float in the air, reducing the amount of softening liquid actually attached to the wood. At the same time, the wood surface will be damaged due to excessive impact force, affecting the subsequent softening effect and product quality.

[0049] The key to ensuring that the wood is fully softened is to spray 80-120g of liquid per square meter of wood surface. Too little spraying will not allow the softening liquid to completely cover the wood surface and penetrate deep into the interior, resulting in insufficient softening and affecting the effect of the subsequent embossing process. Too much spraying will cause a waste of softening liquid and form too thick a liquid layer on the wood surface, prolonging the drying time and causing problems such as cracking during the drying process, destroying the flatness of the wood surface.

[0050] The use of uniform and continuous multi-layer spraying can make the softening liquid form a more uniform coating on the wood surface. Multi-layer spraying can ensure that all parts of the wood can fully contact the softening liquid, especially for the texture and pores on the wood surface, which can be better filled and softened; uniform and continuous spraying can avoid excessive or insufficient local softening, so that the softening degree of the entire wood surface is consistent, providing a stable material state for subsequent embossing operations, and improving the embossing quality and product consistency.

[0051] Keeping the vertical distance between the spray gun and the wood surface at 20-30cm can ensure that the softening liquid is sprayed onto the wood at the best angle and coverage; if the distance is too close, the softening liquid spray will be too concentrated, which may easily cause excessive and uneven local spraying; if the distance is too far, the spray will be dispersed and unable to accurately cover the wood surface, resulting in some areas not getting enough softening liquid, affecting the softening effect and the appearance quality of the product.

[0052] The 10-15 minute interval between each spraying layer is to allow each layer of softening liquid enough time to dry and penetrate. If the interval is too short, the newly sprayed softening liquid will mix with the undried previous layer of softening liquid, causing the softening liquid to flow and uneven thickness, affecting the drying and softening effects; if the interval is too long, it will increase the time cost of the entire spraying process and reduce production efficiency; the appropriate interval time can ensure that each layer of softening liquid can dry and play a softening role in the best state, thereby achieving uniform softening of the wood.

[0053] In the finished product processing stage, cutting and trimming operations are crucial, and surface grinding and polishing are important steps to improve the quality of high-tech wood embossed boards in finished product processing. By cutting high-tech wood embossed boards, their size can be accurately matched to the actual application requirements; at the same time, trimming can effectively remove the burrs and unevenness that appear during the production process of embossed boards, making the edges of the products neat and smooth, which not only improves the appearance quality, but also prevents scratches and damage caused by rough edges during subsequent use, ensuring the safety and aesthetics of the products.

[0054] Using fine sandpaper to lightly polish the surface can eliminate minor flaws on the embossed board, such as uneven embossing and bulges caused by drying of softening liquid, making the surface smoother; using fine sandpaper with a particle size of 240-320 mesh can effectively remove minor surface flaws without leaving too deep scratches on the wood surface. Then polishing can greatly enhance the smoothness of the surface of the technical wood and make it feel delicate; under high-speed friction of 2500-3000 revolutions per minute, the minor scratches and uneven parts remaining on the wood surface after polishing can be effectively smoothed.

[0055] Preferably, the step S5 of finished product processing comprises the following specific steps: S51 Cutting and trimming: Cut and trim the embossed engineered wood panels to meet the size requirements of actual applications; S52 Surface grinding and polishing: Use 240-320 mesh fine sandpaper to lightly grind the surface of the technological wood embossed board, and then polish it with a polishing machine with a speed of 2500-3000 revolutions per minute to enhance the smoothness and touch of the surface to obtain the final finished embossed technological wood.

[0056] In summary, the present invention has the following beneficial effects: 1. The softening treatment of the present invention significantly enhances the plasticity of the technical veneer, effectively increases the embossing depth, and reduces the embossing rebound effect, making the embossed pattern more three-dimensional, greatly improving the visual effect and added value; the softened wood is smoother during the hot pressing and embossing process, and by optimizing the hot pressing and embossing parameters, deep embossing can be achieved while ensuring that the wood is not damaged, further improving the aesthetics and durability of the product, and comprehensively improving the embossing quality and effect; 2. The present invention uses softening treatment and process optimization to improve production efficiency and stability; softening treatment effectively reduces the risk of material deformation or cracking, thereby reducing downtime caused by material problems and significantly improving overall production efficiency and output; strictly controlling the conditions of each production step can effectively avoid defects in the finished product, ensure the stability of the embossing process, improve product consistency, and further improve production efficiency and stability; 3. The softening liquid formula and polyurethane adhesive formula of the present invention have unique advantages. The synergistic effect of their components improves the performance and embossing stability of the technical wood. The polyurethane adhesive formula shows innovative value in comprehensive performance, cross-linking structure optimization and adaptability to various application environments through the compounding of polyols, mixing of isocyanates and reasonable matching of additives, ensuring good bonding strength and toughness in humid and high temperature environments, and effectively reducing the possibility of debonding and cracking at the embossing. 4. The preferred substrate multilayer board and blockboard of the present invention have good stability and strength, can withstand the pressure and temperature changes during the embossing process, and effectively guarantee the product quality; by softening the wood and combining the optimization of hot pressing parameters, the temperature and pressure of embossing are reduced, and deeper embossing is achieved without damaging the wood, which not only improves the aesthetics of the product, but also enhances the durability of the product, reflecting the advantages of process synergy; 5. The method for producing embossed technological wood of the present invention has good operability and wide applicability. The adhesives and primers used reduce the emission of harmful volatiles, meet environmental protection requirements, and embody environmental protection characteristics. At the same time, it can adapt to technological veneers of different types and thicknesses to meet the needs of different customers. The present invention has achieved a technological breakthrough by softening the veneer and optimizing the process, showing significant advantages in embossing effect, product quality and stability. DETAILED DESCRIPTION

[0057] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law. Example 1

[0058] S1 prepare raw materials: 45 parts of 25% ammonia water, 20 parts of polyethylene glycol, 1.5 parts of sodium dodecylbenzene sulfonate, 35 parts of water, and 3 parts of nanocellulose are mixed in weight percentage, and stirred to obtain softening liquid A; a multilayer board that has been pressed, dyed and modified is selected as the technical wood substrate with a thickness of 10 mm. The raw material is poplar wood. The surface of the technical wood substrate is preliminarily sanded to remove impurities and surface unevenness, and a layer of primer is evenly applied on the sanded surface; an environmentally friendly polyurethane paint primer is applied by electrostatic spraying technology, the temperature is 25°C, the relative humidity is 60%, the spraying voltage is 50kV, the spraying current is 0.3A, and the spraying distance is 20cm; the primer formula includes: 40 parts of vegetable oil-based polyols, 25 parts of polyether polyols, 25 parts of aliphatic isocyanates, 2 parts of nano titanium dioxide, 0.3 parts of ultraviolet absorbers, 0.5 parts of antioxidants, and 0.2 parts of nano silver; S2 Preparation of high-tech veneer veneer panel B: Put the processed substrate into a roller coating glue machine, and use a rubber roller to apply glue. The adhesive used is a polyurethane adhesive, and the formula includes: 50 parts of polyester polyol, 30 parts of polyether polyol, 20 parts of toluene diisocyanate, 50 parts of diphenylmethane diisocyanate, 0.2 parts of dibutyltin dilaurate, 10 parts of 1,4-butanediol, 10 parts of dioctyl phthalate, 20 parts of calcium carbonate, 0.3 parts of benzotriazole ultraviolet absorber, and 0.5 parts of hindered phenol antioxidant; the amount of glue applied is 90g / m²; put a 0.5 mm thick high-tech veneer on the glued substrate, put it into a hot press for hot pressing, the pressure applied by the hot press is 13MPa, the temperature is 110℃, and the time is 5 minutes, to obtain the high-tech veneer veneer panel B; S3 Preparation of pre-treated veneer board C: clean the surface of the technical veneer veneer board B, set the temperature to 20°C, the relative humidity to 50%, control the spray gun pressure at 0.3MPa, spray 100g per square meter of wood surface, adopt a uniform and continuous multi-layer spraying method, keep the vertical distance between the spray gun and the wood surface at 25cm, spray each layer for 12 minutes, spray softening liquid A on the surface, dry it naturally for 4 hours, control the surface technical veneer moisture content at 25%, and prepare pre-treated veneer board C; S4 Preparation of technological wood embossed board: Put the pretreated veneer board C into the embossing machine for embossing at a temperature of 70°C and a pressure of 9MPa to obtain a technological wood embossed board; S5 Finished product processing: Cut and trim the embossed technology wood board to meet the size requirements of actual applications; use 280-grit fine sandpaper to lightly grind the surface of the embossed technology wood board, and then polish it with a polishing machine at a speed of 2800 revolutions per minute to enhance the smoothness and touch of the surface to obtain the final finished embossed technology wood. Example 2

[0059] S1 prepare raw materials: 40 parts of 20% ammonia water, 18 parts of polyethylene glycol, 1 part of sodium dodecylbenzene sulfonate, 30 parts of water, and 2 parts of nanocellulose are mixed in weight percentage, and stirred to obtain softening liquid A; selected pressed, dyed and modified blockboard as the technical wood substrate, with a thickness of 3mm, and the raw material is birch, and the surface of the technical wood substrate is preliminarily sanded to remove impurities and surface uneven parts, and a layer of primer is evenly applied on the sanded surface; electrostatic spraying technology is used to apply environmentally friendly polyurethane paint primer, the temperature is 10℃, the relative humidity is 40%, the spraying voltage is 30kV, the spraying current is 0.1A, and the spraying distance is 15cm; the primer formula includes: 30 parts of vegetable oil-based polyols, 20 parts of polyether polyols, 20 parts of aliphatic isocyanates, 1 part of nano titanium dioxide, 0.2 parts of ultraviolet absorbers, 0.3 parts of antioxidants, and 0.1 parts of nano silver; S2 Preparation of high-tech veneer veneer panel B: Put the processed substrate into a roller coating glue machine, and use a rubber roller to apply glue. The adhesive used is a polyurethane adhesive, and the formula includes: 40 parts of polyester polyol, 20 parts of polyether polyol, 15 parts of toluene diisocyanate, 45 parts of diphenylmethane diisocyanate, 0.05 parts of dibutyltin dilaurate, 5 parts of 1,4-butanediol, 5 parts of dioctyl phthalate, 10 parts of calcium carbonate, 0.1 parts of benzotriazole ultraviolet absorber, and 0.1 parts of hindered phenol antioxidant; the amount of glue applied is 60g / m²; put a 0.5mm thick high-tech veneer on the glued substrate, put it into a hot press for hot pressing, the pressure applied by the hot press is 10MPa, the temperature is 100℃, and the time is 3 minutes, to obtain the high-tech veneer veneer panel B; S3: preparing pre-treated veneer board C: cleaning the surface of the technical veneer veneer board B, keeping the temperature at 15°C, the relative humidity at 40%, controlling the spray gun pressure at 0.2MPa, spraying 80g per square meter of wood surface, using a uniform and continuous multi-layer spraying method, keeping the vertical distance between the spray gun and the wood surface at 20cm, spraying each layer at an interval of 10 minutes, spraying softening liquid A on the surface, drying naturally for 2 hours, controlling the surface moisture content of the technical veneer at 20%, and preparing the pre-treated veneer board C; S4 Preparation of technological wood embossed board: Put the pretreated veneer board C into the embossing machine for embossing at a temperature of 60° C. and a pressure of 6 MPa to obtain a technological wood embossed board; S5 Finished product processing: Cut and trim the embossed technology wood board to meet the size requirements of actual applications; use 240-grit fine sandpaper to lightly grind the surface of the embossed technology wood board, and then polish it with a polishing machine at a speed of 2500 revolutions per minute to enhance the smoothness and touch of the surface to obtain the final finished embossed technology wood. Example 3

[0060] S1 prepare raw materials: 50 parts of 30% ammonia water, 22 parts of polyethylene glycol, 2 parts of sodium dodecylbenzene sulfonate, 40 parts of water, and 5 parts of nanocellulose are mixed in weight percentage, and stirred to obtain softening liquid A; a multilayer board that has been pressed, dyed and modified is selected as the technical wood substrate with a thickness of 18mm. The raw material is pine wood. The surface of the technical wood substrate is preliminarily sanded to remove impurities and surface uneven parts, and a layer of primer is evenly applied on the sanded surface; an environmentally friendly polyurethane paint primer is applied by electrostatic spraying technology, the temperature is 35°C, the relative humidity is 80%, the spraying voltage is 80kV, the spraying current is 0.5A, and the spraying distance is 30cm; the primer formula includes: 50 parts of vegetable oil-based polyols, 30 parts of polyether polyols, 30 parts of aliphatic isocyanates, 3 parts of nano titanium dioxide, 0.5 parts of ultraviolet absorbers, 0.8 parts of antioxidants, and 0.3 parts of nano silver; S2 Preparation of high-tech veneer veneer panel B: Put the processed substrate into a roller coating glue machine, and use a rubber roller to apply glue. The adhesive used is a polyurethane adhesive, and the formula includes: 60 parts of polyester polyol, 40 parts of polyether polyol, 30 parts of toluene diisocyanate, 55 parts of diphenylmethane diisocyanate, 0.3 parts of dibutyltin dilaurate, 15 parts of 1,4-butanediol, 15 parts of dioctyl phthalate, 30 parts of calcium carbonate, 0.5 parts of benzotriazole ultraviolet absorber, and 1 part of hindered phenol antioxidant; the amount of glue applied is 120g / m²; put a 3.0 mm thick high-tech veneer on the glued substrate, put it into a hot press for hot pressing, the pressure applied by the hot press is 16MPa, the temperature is 120℃, and the time is 8 minutes, to obtain the high-tech veneer veneer panel B; S3 Preparation of pre-treated veneer board C: Clean the surface of the technical veneer veneer board B, set the temperature to 30°C, the relative humidity to 60%, control the spray gun pressure at 0.4MPa, spray 120g per square meter of wood surface, adopt a uniform and continuous multi-layer spraying method, keep the vertical distance between the spray gun and the wood surface at 30cm, and spray each layer for 15 minutes. Spray softening liquid A on the surface, dry it naturally for 6 hours, control the surface moisture content of the technical veneer at 30%, and prepare the pre-treated veneer board C; S4 Preparation of technological wood embossed board: Put the pretreated veneer board C into an embossing machine for embossing at a temperature of 80° C. and a pressure of 12 MPa to obtain a technological wood embossed board; S5 Finished product processing: Cut and trim the embossed technology wood board to meet the size requirements of actual applications; use 320-grit fine sandpaper to lightly grind the surface of the embossed technology wood board, and then polish it with a polishing machine at a speed of 3000 revolutions per minute to enhance the smoothness and touch of the surface, and obtain the final finished embossed technology wood.

[0061] Comparative Example 1 S1 prepare raw materials: 45 parts of 25% ammonia water and 35 parts of water are mixed in weight percentage, stirred and mixed evenly to obtain ordinary softening liquid D; a multi-layer board that has been pressed, dyed and modified is selected as the technical wood substrate with a thickness of 10mm. The raw material is poplar wood. The surface of the technical wood substrate is preliminarily sanded to remove impurities and surface unevenness, and a layer of primer is evenly applied on the sanded surface; an environmentally friendly polyurethane paint primer is applied by electrostatic spraying technology, the temperature is 25°C, the relative humidity is 60%, the spraying voltage is 50kV, the spraying current is 0.3A, and the spraying distance is 20cm; the primer formula includes: 40 parts of vegetable oil-based polyols, 25 parts of polyether polyols, 25 parts of aliphatic isocyanates, 2 parts of nano titanium dioxide, 0.3 parts of ultraviolet absorbers, 0.5 parts of antioxidants, and 0.2 parts of nano silver; The remaining steps are the same as those in Example 1 to obtain the final finished embossed technical wood.

[0062] Comparative Example 2 S1 prepare raw materials: 45 parts of 25% ammonia water, 20 parts of polyethylene glycol, 1.5 parts of sodium dodecylbenzene sulfonate, 35 parts of water, and 3 parts of nanocellulose are mixed in weight percentage, and stirred to obtain softening liquid A; a multi-layer board that has been pressed, dyed and modified is selected as the technical wood substrate with a thickness of 10mm. The raw material is poplar wood. The surface of the technical wood substrate is preliminarily sanded to remove impurities and surface unevenness, and a layer of primer is evenly applied on the sanded surface; a conventional non-environmentally friendly primer phenolic primer is applied by electrostatic spraying technology, the temperature is 25°C, the relative humidity is 60%, the spraying voltage is 50kV, the spraying current is 0.3A, and the spraying distance is 20cm; the primer formula includes: 40 parts of modified phenolic resin, 25 parts of red lead anti-rust color filler, 8 parts of additives, and 10 parts of xylene; The remaining steps are the same as those in Example 1 to obtain the final finished embossed technical wood.

[0063] Comparative Example 3 In step S2, in preparing the technological veneer veneer panel B, the processed substrate is placed in a roller coating glue coating machine, and glue is applied with a rubber roller. The adhesive used is a traditional adhesive, and the amount of glue applied is 90 g / m²; a technological veneer with a thickness of 0.5 mm is placed on the glued substrate, and is placed in a hot press for hot pressing. The pressure applied by the hot press is 13 MPa, the temperature is 110° C., and the time is 5 minutes to obtain the technological veneer veneer panel B; The remaining steps are the same as those in Example 1 to obtain the final finished embossed technical wood.

[0064] 1. Experimental Methods A series of performance tests were conducted on the finished embossed technical wood prepared in Examples 1-3 and Comparative Examples 1-3, including indicators such as formaldehyde emission, bonding strength, surface bonding strength, surface wear resistance, and color fastness.

[0065] 1.1 Formaldehyde emission The test is conducted in accordance with GB / T 39600-2021 "Classification of Formaldehyde Emissions from Artificial Boards and Their Products" and T / CNFPIA 1003-2022. These two standards set clear classification requirements and testing specifications for the formaldehyde emissions of artificial boards and their products from different perspectives, ensuring the scientificity and accuracy of the test results, and being able to fully reflect the formaldehyde emissions of products in different usage environments.

[0066] The test is carried out under specific temperature conditions, and two temperature nodes of 23°C and 30°C are set respectively. The prepared embossed technical wood of the embodiment of the present invention and the embossed technical wood of the control group are placed in an environmental chamber that meets the standard requirements. The temperature, humidity, air flow rate and other conditions in the environmental chamber are strictly controlled in accordance with the standard provisions. Within the specified time interval, the formaldehyde concentration in the air in the environmental chamber is continuously monitored and data is collected through professional formaldehyde detection instruments, such as mature detection technologies such as spectrophotometer or gas chromatography. After a certain period of stabilization, the formaldehyde release of the embossed technical wood at different temperatures is accurately calculated based on the collected data and the calculation formula in the corresponding standard.

[0067] 1.2 Bonding strength The test is carried out in accordance with GB / T 34722-2017 "Impermeable Paper Laminated Wood Flooring". This standard sets detailed technical requirements and testing specifications for the bonding strength of wood flooring and other similar products, and objectively evaluates the firmness of the bonding connection between the layers of the product.

[0068] Testing method: First, cut specimens of specified size and shape from the prepared embossed technical wood to ensure that the specimens are representative and meet the size specifications required by the standard. Then, fix the specimens on a professional bonding strength testing device and apply gradually increasing tension to the specimens to simulate the external forces that may be applied during actual use until the bonding part of the specimen is damaged. During the test, the equipment will record the magnitude of the tension and the state of the bonding part of the specimen when it is damaged in real time. Finally, according to the calculation formula specified in the GB / T 34722-2017 standard and the data collected during the test, the bonding strength value of the embossed technical wood is accurately calculated.

[0069] 1.3 Surface bonding strength The test is also based on GB / T 34722-2017 "Impregnated Paper Laminated Wood Flooring" standard. This standard also has clear provisions for the test of surface bonding strength. Through unified standard specifications, the performance differences of different embossed technical wood in surface bonding can be compared fairly and accurately.

[0070] Similar to the gluing strength test, first prepare a specific specimen that meets the standard size requirements from the embossed technical wood. Place the specimen on a device specifically used for surface gluing strength testing. The device usually uses a specific fixture and loading device to accurately apply a tensile force perpendicular to the surface to the gluing part of the specimen surface. During the test, the tensile force is gradually increased until the gluing layer on the surface of the specimen is damaged. During this period, the equipment continuously records the tensile force value and related conditions at the time of damage. Finally, according to the calculation method specified in the GB / T 34722-2017 standard, the surface gluing strength index of the embossed technical wood is calculated based on the test data.

[0071] 1.4 Surface wear resistance The test was conducted in accordance with GB / T 34722-2017 "Impregnated Paper Laminated Wood Flooring". This standard sets detailed evaluation indicators and testing procedures for the surface wear resistance of products such as wood floors, and can be used for comparative testing of the surface wear resistance of the embossed technical wood of the present invention and the embossed technical wood of the control group.

[0072] Select a certain area of ​​embossed wood surface as the test area, and fix the embossed wood on a professional surface wear test equipment, such as Taber abrasion tester. Install a specified model of grinding wheel on the test equipment, and perform the test operation according to the load, speed, friction times and other parameters set in the standard. After the grinding wheel rubs the embossed wood surface for a certain number of times, the wear depth, weight loss or appearance change of the embossed wood surface is measured, and the surface wear resistance of the embossed wood is quantitatively evaluated according to the judgment rules in GB / T34722-2017 standard to determine its surface wear grade or specific wear resistance value.

[0073] 1.5 Color fastness The test is carried out in accordance with the relevant standard GB / T 8427-2019 "Textiles - Tests for colour fastness - colour fastness to artificial light: Xenon arc fading". Although this standard is mainly for textiles, the principle can be used for the colour fastness test of embossed technical wood.

[0074] Testing method: First, select a representative embossed technical wood specimen, the specimen size must meet the standard requirements, such as a square specimen with a side length of 10 cm. Then fix the specimen in a professional color fastness testing device.

[0075] There are different types of testing to simulate the effects that different real-world environments may have on color: Light fastness test: By simulating natural sunlight conditions, set certain light intensity, lighting time, temperature, humidity and other environmental parameters. The equipment uses a xenon arc lamp as the light source and continuously irradiates the test piece for a specified time of 168 hours. After the irradiation, the color of the test piece is compared with the original test piece that has not been irradiated. The color change value ΔE value is measured using a professional color measurement instrument, a colorimeter, and the light fastness grade of the embossed technical wood is determined according to the judgment rules in the standard.

[0076] Color fastness to rubbing test: simulate the friction that may occur in daily use. Use a friction tester to rub the surface of the specimen back and forth 100 times with a standard friction cloth at a specified load of 9N. After rubbing, observe the transfer of the surface color of the specimen to the friction cloth and the change of the surface color of the specimen itself. Use a color measuring instrument to measure the color change value and determine the color fastness to rubbing grade according to the standard judgment rules.

[0077] Through the above color fastness test, the color retention ability of the embossed technical wood of the present invention under different use environments can be comprehensively evaluated, providing an important basis for product quality control and market application.

[0078] 2. Experimental results The test results of formaldehyde emission, bonding strength, surface bonding strength, surface wear resistance, color fastness and other indicators of the embossed technical wood prepared in Examples 1-3 and Comparative Examples 1-3 are shown in the table below.

[0079] Table 1 Comparison of properties of embossed engineered wood prepared in each group

[0080] 2.1 Formaldehyde emission The embossed technical wood prepared in Examples 1-3 has formaldehyde releases of 0.026 mg / m³, 0.028 mg / m³ and 0.027 mg / m³ at 23°C, and 0.032 mg / m³, 0.038 mg / m³ and 0.034 mg / m³ at 30°C; these data show that the formaldehyde releases of the embodiments of the present invention are at a low level at different temperatures. The formaldehyde releases of Comparative Examples 1-3 are significantly higher than those of the embodiments. The embossed technical wood prepared in Comparative Example 1 has formaldehyde releases of 0.078 mg / m³ and 0.118 mg / m³ at 23°C and 30°C, respectively, the formaldehyde releases of Comparative Example 2 are 0.177 mg / m³ (23°C) and 0.136 mg / m³ (30°C), and the formaldehyde releases of Comparative Example 3 are 0.121 mg / m³ (23°C) and 0.142 mg / m³ (30°C).

[0081] Comparative Example 1 simplifies the softening liquid formula, affects the internal structure of the wood and the subsequent treatment effect, and indirectly leads to an increase in formaldehyde release; Comparative Example 2 uses a conventional non-environmentally friendly primer phenolic primer, which itself contains more formaldehyde release sources; Comparative Example 3 uses a traditional adhesive, which releases more volatile organic compounds, including formaldehyde, during the curing process, thereby leading to an increase in formaldehyde release. The present invention uses environmentally friendly materials and processes, and the environmentally friendly polyurethane paint primer used in the raw material preparation stage has an optimized formula that reduces components that may produce harmful volatiles. At the same time, strict control of each step in the entire production process also helps to reduce formaldehyde release.

[0082] 2.2 Bonding strength and surface bonding strength The average bonding strength of Examples 1-3 is between 1.62-1.71 N / mm², and the average surface bonding strength is between 1.50-1.68 N / mm²; this indicates that the bonding process of the present invention can achieve good bonding between the technical veneer and the substrate and between the layers. The bonding strength and surface bonding strength of Comparative Examples 1-3 are lower than those of the Examples. The bonding strength of Comparative Example 1 is 1.11 N / mm², and the surface bonding strength is 1.08 N / mm²; the bonding strength of Comparative Example 2 is 1.01 N / mm², and the surface bonding strength is 0.88 N / mm²; the bonding strength of Comparative Example 3 is 1.22 N / mm², and the surface bonding strength is 1.01 N / mm².

[0083] Data comparison and analysis show that the polyurethane adhesive formula used in the present invention ensures advantages in comprehensive performance, cross-linking structure optimization and adaptability to various application environments through polyol compounding, isocyanate mixing and reasonable matching of additives, thereby improving the bonding strength and surface bonding strength. However, the simplified softening liquid formula in Comparative Example 1 and the use of non-environmentally friendly primer in Comparative Example 2 both affect the surface state of the wood, making the bonding conditions worse, thereby reducing the bonding strength and surface bonding strength; Comparative Example 3 uses a traditional adhesive, which is not as good as the polyurethane adhesive prepared in the present invention in terms of bonding force, flexibility and adaptability to different materials, resulting in poor bonding effect.

[0084] 2.3 Surface wear resistance The wear values ​​of Examples 1-3 are 50 mg / 100r, 43 mg / 100r and 45 mg / 100r, respectively, indicating that the embossed technical wood prepared by the present invention has good surface wear resistance. The wear values ​​of Comparative Examples 1-3 are significantly higher than those of the Examples, namely 143 mg / 100r, 140 mg / 100r and 132 mg / 100r, respectively, indicating that the wear resistance of the embossed technical wood of Comparative Examples 1-3 is lower than that of Examples 1-3.

[0085] The simplified softening liquid formula of Comparative Example 1 affects the surface properties of wood, the non-environmentally friendly primer used in Comparative Example 2 changes the surface structure of wood, and the traditional adhesive used in Comparative Example 3 has an adverse effect on the surface properties of wood, all of which lead to a decrease in surface wear resistance. However, the technological veneer of the present invention is dried, insect-proof, and anti-corrosive, and has a smooth and durable surface. In the process of finished product processing, the surface grinding and polishing operations further improve the smoothness and hardness of the surface, thereby enhancing the wear resistance.

[0086] 2.4 Color fastness In terms of color fastness to light, the ΔE values ​​of Examples 1-3 are between 1.4-1.6; in terms of color fastness to rubbing, the ΔE values ​​are between 1.1-1.3; this indicates that the embossed technical wood prepared by the present invention has good color retention. The color fastness of Comparative Examples 1-3 is obviously inferior to that of the Examples, and in terms of color fastness to light, the ΔE values ​​are between 2.5-3.0; in terms of color fastness to rubbing, the ΔE values ​​are between 2.0-2.3.

[0087] Comparative Example 1 simplifies the softening liquid formula, Comparative Example 2 uses a non-environmentally friendly primer, and Comparative Example 3 uses a traditional adhesive, which affects the combination of color and wood and the light aging and friction resistance of the material itself, resulting in a decrease in color fastness. However, the embossed technical wood manufacturing method provided by the present invention allows the color to be closely combined with the wood due to the processing technology in the production process, and the material itself also has certain light aging and friction resistance, so that the color is not easy to fade under light and friction conditions.

[0088] In summary, through comparative analysis with the comparative examples, it can be seen that the embodiments of the present invention show obvious advantages in formaldehyde emission, bonding strength, surface bonding strength, surface wear resistance and color fastness, which fully proves the rationality and superiority of the production method and material selection of the present invention.

[0089] The invention provides a method for making embossed technological wood. The method significantly enhances the plasticity of technological wood veneer through a unique softening treatment, increases the embossing depth and reduces the rebound effect, improves the visual effect and added value, optimizes the hot pressing and embossing parameters at the same time, realizes deep embossing without damaging the wood, and improves the aesthetics and durability. The softening treatment and process optimization are used to reduce the risk of material deformation or cracking, reduce downtime, improve production efficiency and output, and strictly control the production step conditions to ensure product consistency. The softening liquid and the polyurethane adhesive have a unique formula, and the components synergistically improve the performance of the technological wood and the embossing stability. The adhesive has good bonding strength and toughness in a humid and high temperature environment, reduces debonding and cracking, and the adhesive and the primer meet environmental protection requirements. The preferred substrate has good stability and strength, and the product quality is improved by combining the softening of the wood and the optimization of the hot pressing parameters. The making method has strong operability and wide applicability, can adapt to technological wood veneers of different types and thicknesses, and meet customer needs.

Claims

1. A method for producing embossed technical wood, characterized in that: Specifically include: S1 prepare raw materials: prepare softening liquid A by weight percentage by mixing 20-50 parts of ammonia water, 10-30 parts of polyethylene glycol, 1-3 parts of sodium dodecylbenzene sulfonate, 15-40 parts of water, and 2-8 parts of nanocellulose; process the technical wood substrate; S2: preparing the technological veneer veneer panel B: placing the processed substrate into a glue coating machine, applying glue with a rubber roller, and applying the adhesive in an amount of 60-120 g / m²; placing the technological veneer on the glued substrate, and putting it into a hot press for hot pressing, the pressure applied by the hot press is 10-16 MPa, the temperature is 100-120° C., and the time is 3-8 minutes, to obtain the technological veneer veneer panel B; S3 Preparation of pre-treated veneer board C: Clean the surface of the technical veneer veneer board B, spray softening liquid A, dry it naturally for 2-6 hours, and control the surface moisture content of the technical veneer to be 20-30%, so as to obtain the pre-treated veneer board C; S4 Preparation of technological wood embossed board: Put the pretreated veneer board C into an embossing machine for embossing at a temperature of 60-80°C and a pressure of 6-12MPa to obtain a technological wood embossed board; S5 Finished product processing: cutting, trimming, grinding and polishing the technological wood embossed board to obtain the finished embossed technological wood.

2. The method for producing embossed technical wood according to claim 1, characterized in that: The step S1 of preparing raw materials includes: S11: prepare softening liquid A: mix 40-50 parts of 20-30% ammonia water, 18-22 parts of polyethylene glycol, 1-2 parts of sodium dodecylbenzene sulfonate, 30-40 parts of water, and 2-5 parts of nanocellulose according to weight percentage; S12 substrate processing: Select a pressed, dyed and modified technological wood substrate with a thickness of 3-18mm. Perform preliminary sanding on the surface of the technological wood substrate to remove impurities and surface unevenness, and evenly apply a layer of primer on the sanded surface.

3. The method for producing embossed technical wood according to any one of claims 1 or 2, characterized in that: The substrate in step S1 is one of multilayer board and blockboard, and the raw material is one of poplar, birch and pine; the multilayer board as the technical wood substrate has a thickness of 3-18 mm, and the blockboard as the technical wood substrate has a thickness of 12-18 mm; The primer is an environmentally friendly polyurethane paint, and its formula includes: 30-50 parts of vegetable oil-based polyol, 20-30 parts of polyether polyol, 20-30 parts of aliphatic isocyanate, 1-3 parts of nano titanium dioxide, 0.2-0.5 parts of ultraviolet absorber, 0.3-0.8 parts of antioxidant, and 0.1-0.3 parts of nano silver.

4. The method for making embossed technical wood according to claim 3, characterized in that: The primer construction method in step S12 adopts electrostatic spraying technology to apply environmentally friendly polyurethane paint primer, the temperature is 10-35°C, the relative humidity is 40-80%, the spraying voltage is 30-80kV, the spraying current is 0.1-0.5A, and the spraying distance is 15-30cm.

5. The method for producing embossed technical wood according to claim 1, characterized in that: The thickness of the technological veneer in step S2 is 0.5-3.0 mm, and after drying, insect-proofing and anti-corrosion treatment, the surface is smooth and durable.

6. The method for producing embossed technical wood according to claim 1, characterized in that: The adhesive in step S2 is a polyurethane adhesive, and the formula includes: 40-60 parts of polyester polyol, 20-40 parts of polyether polyol, 15-30 parts of toluene diisocyanate, 45-55 parts of diphenylmethane diisocyanate, 0.05-0.3 parts of dibutyltin dilaurate, 5-15 parts of 1,4-butanediol, 5-15 parts of dioctyl phthalate, 10-30 parts of calcium carbonate, 0.1-0.5 parts of benzotriazole ultraviolet absorber, and 0.1-1 parts of hindered phenol antioxidant.

7. The method for making embossed technical wood according to claim 1, characterized in that: The spraying environment temperature of the softening liquid in step S3 is 15-30° C., the relative humidity is 40-60%, the spray gun pressure is controlled at 0.2-0.4 MPa, the spraying amount per square meter of wood surface is 80-120 g, a uniform and continuous multi-layer spraying method is adopted, the vertical distance between the spray gun and the wood surface is maintained at 20-30 cm, and the interval between each layer of spraying is 10-15 minutes.

8. The method for producing embossed technical wood according to claim 1, characterized in that: The step S5 of finished product processing comprises the following specific steps: S51 Cutting and trimming: Cut and trim the embossed engineered wood panels to meet the size requirements of actual applications; S52 Surface grinding and polishing: Use 240-320 mesh fine sandpaper to lightly grind the surface of the technological wood embossed board, and then polish it with a polishing machine with a speed of 2500-3000 revolutions per minute to enhance the smoothness and touch of the surface to obtain the final finished embossed technological wood.

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