Low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wood process

Abstract

The invention discloses a low-density high-strength formaldehyde-free moistureproof anti-deformation wood process, and relates to the field of wood processing, and a plastic framework, a wood filler and a fine rice flour coating are involved in the low-density high-strength formaldehyde-free moistureproof anti-deformation wood process. According to the process, the plastic framework is used as the framework filling wood filler, the produced furniture wooden piece semi-finished product has the use feeling similar to that of solid wood furniture, the fine wood powder coating forms a fine shell on the outer side, the good touch feeling is achieved, and the furniture wooden piece can be comparable with rare solid wood, and the furniture wooden piece produced through the process has the advantages that the material cost is reduced; glue and particles are tightly combined through accurate mixing, and the coating strength is enhanced; the acrylate emulsion and the benzotriazole endow the moisture-proof performance; the thickening agent and the composite structure improve the non-deformability, so that the furniture wooden part has a certain adaptation range to the environment temperature and humidity, the advantages of low density, high strength, no formaldehyde, moisture resistance and deformation resistance of the coating can be fully exerted, and the coating is suitable for various scenes.

Description

Technical Field

[0001] The invention relates to the technical field of wood processing, and in particular to a low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wood processing technology. Background Art

[0002] Wooden furniture, especially solid wood furniture, has become an important part of modern homes with its natural, environmentally friendly, durable and diverse design styles. Wooden furniture is mainly divided into solid wood furniture and other wooden furniture. Solid wood furniture refers to furniture made of solid wood, which is generally divided into pure solid wood furniture and all solid wood furniture.

[0003] In the prior art, pure solid wood furniture is expensive, and untreated solid wood furniture is prone to corrosion, moisture and deformation. In the production process of granular furniture wood parts, a large amount of glue is used to bond materials, which makes the furniture wood parts environmentally unfriendly and releases formaldehyde. Therefore, a low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden process is needed to meet people's needs. Summary of the invention

[0004] The purpose of the present invention is to provide a low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden process to solve the problems of high cost of pure solid wood furniture proposed in the above background technology, and the problem that untreated solid wood furniture is easy to corrode, easy to be affected by moisture, and easy to deform. In the production process of granular furniture wooden parts, a large amount of glue bonding materials will be used, resulting in the problem that the wooden parts of the furniture are not environmentally friendly and release formaldehyde.

[0005] To achieve the above object, the present invention provides the following technical solutions: a low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden process, comprising a plastic skeleton, a wood filler and a fine rice powder coating; The plastic skeleton specifically includes: ‌ The content of polyamide resin is between 80% and 85%, the content of glass fiber is between 10% and 15%, and the content of calcium carbonate is between 5% and 10%, which constitute the basic cost of the plastic skeleton; Trace elements, one or more of copper elements such as cuprous iodide, cuprous bromide, cupric bromide, cuprous chloride, and cupric acetate, with the content of trace elements ranging from 0.02 to 0.2%; Enhancer, one or more of potassium bromide, sodium bromide, lithium bromide, calcium bromide, and magnesium bromide alkali metal, the content of the enhancer is 0.05 to 0.5%; Wood fillers include: The wood filler includes large wood particles and formaldehyde-free glue, and the mixing ratio W of the wood particles and the formaldehyde-free glue is 95:5; The diameter of large wood particles ranges from 3mm to 8mm; The ingredients of formaldehyde-free glue: polyvinyl alcohol 6% to 16%, BPA cross-linking agent 9% to 21%, YH1 complexing agent 14% to 16%, water 16% to 30%, oxidized starch 20% to 25%; Fine wood powder coatings specifically include: Fine wood powder coating includes small-grain wood particles and waterproof formaldehyde-free glue; The diameter of small wood particles is between 0.05mm and 0.1mm; The ingredients of waterproof formaldehyde-free glue: polyvinyl alcohol 5%~10%, acrylic emulsion 30%~40%, hydroxyethyl cellulose 0.5%~1%, silicone defoamer 0.2%~1%, deionized water 30%~35%, and benzotriazole 0.5%~1%.

[0006] Preferably, the process comprises the following steps: Raw material pretreatment: Polyamide resin: Check the appearance of the polyamide resin to ensure that there are no impurities or lumps. If the resin has a high moisture content, it needs to be dried. Generally, it can be dried in a blast drying oven at 80 to 120°C for 4 to 8 hours to remove moisture and prevent bubble defects in subsequent processing; Glass fiber: Select glass fiber of appropriate length and diameter, usually 3 to 6 mm in length, and treat the surface of the glass fiber. A coupling agent (such as silane coupling agent) may be used to enhance the interfacial bonding between the glass fiber and the polyamide resin. Soak the glass fiber in a diluted coupling agent solution and then dry it at 100 to 120°C. Calcium carbonate: Choose calcium carbonate with appropriate particle size, generally 1 to 10 μm. To improve the compatibility of calcium carbonate with resin, it can be surface modified and coated with stearic acid; Trace elements and enhancers: Ensure that the purity and particle size of trace elements and enhancers meet the requirements. If necessary, they can be ground to ensure uniform dispersion; Equipment preparation: high-speed mixer, twin-screw extruder, drying equipment, metering equipment; Initial mixing Measurement: Accurately weigh polyamide resin (80% to 85%), glass fiber (10% to 15%), calcium carbonate (5% to 10%), trace elements (0.02% to 0.2%) and reinforcing agent (0.05% to 0.5%) according to the formula; Adding materials: Add the weighed polyamide resin into the high-speed mixer, start stirring, and control the stirring speed at 300 to 500 r / min; Add trace elements and enhancers: During the stirring process, slowly add trace elements and enhancers, and continue stirring for 5 to 10 minutes to make the trace elements and enhancers evenly dispersed in the polyamide resin; Add calcium carbonate: Then add the surface treated calcium carbonate and stir for 10 to 15 minutes to ensure that the calcium carbonate and resin are fully mixed; Add glass fiber: Finally, add the surface treated glass fiber. Since the glass fiber is long, add it slowly and evenly to avoid entanglement. Continue stirring for 15 to 20 minutes to evenly distribute the glass fiber in the mixture; Melt Blending Preheat the twin-screw extruder: Set the temperature of each heating zone of the twin-screw extruder to the melting temperature range of the polyamide resin, generally 220 to 280°C, and preheat so that the screw and barrel reach the set temperature and stabilize.

[0007] Feeding: The preliminarily mixed materials are evenly added into the hopper of the twin-screw extruder through the feeding device. The feeding speed should be adjusted according to the production capacity of the extruder and the screw speed, and is generally controlled at 10 to 30 kg / h.

[0008] Screw speed: Adjust the screw speed of the twin-screw extruder, generally 200 to 400r / min, so that the material can be fully melted, mixed and plasticized under the shearing and conveying action of the screw.

[0009] Shaping: After the materials are melt-blended in the extruder, they are injected into the mold and shaped into a plastic skeleton with five-sided holes; Drying: Place the plastic frame in a forced air drying oven and dry it at 80 to 120°C for 4 to 8 hours to remove moisture and improve the storage stability of the product.

[0010] Preferably, the plastic skeleton is treated with fillers: Raw material pretreatment Wood particles: Screen out large wood particles with a diameter of 3 to 8 mm, remove the bark, soil, sand and stone impurities mixed in them, and steam the wood to reduce the density of the wood material. To ensure the subsequent gluing effect, the wood particles can be dried to control the moisture content to 6% to 12%. It can be dried by natural airing or drying equipment. The drying temperature should not exceed 80°C to prevent the carbonization of the wood particles from affecting the performance of the wooden furniture parts.

[0011] Preparation of formaldehyde-free glue: According to the formula, accurately weigh 6% to 16% of polyvinyl alcohol, 9% to 21% of BPA cross-linking agent, 14% to 16% of YH to 1 complexing agent, 16% to 30% of water, and 20% to 25% of oxidized starch. First, add water to the reactor and heat it to an appropriate temperature (generally 70 to 90°C). Then slowly add polyvinyl alcohol and stir until it is completely dissolved. Then, add BPA cross-linking agent, YH to 1 complexing agent and oxidized starch in turn. Continue to stir and control the reaction temperature and time to allow each component to react fully to make a uniform formaldehyde-free glue. Glue Mixing Add the pretreated wood particles into the drum glue mixer, start the mixer, and slowly add the formaldehyde-free glue to the mixer according to a certain ratio (the mass ratio of glue to wood particles is 1:4 to 1:6) based on the weight of the wood particles. During the process of adding glue, continue to stir so that the glue is evenly attached to the surface of the wood particles. The stirring time is generally controlled at 5 to 15 minutes. The specific time can be adjusted according to the performance of the glue mixer and the state of the wood particles. Paving The wood particles mixed with glue, i.e. wood filler, are conveyed to the mold through a conveyor belt, and the mold is used to fill the wood particles into the pentagonal holes on the plastic frame; Heat curing It will be sent to the hot press for hot pressing. The hot pressing process is a key step in the molding of wooden furniture parts. The formaldehyde-free glue is solidified by heating and pressurizing, and the plastic skeleton and wood filler are molded together to form semi-finished wooden furniture parts. The hot pressing temperature is generally controlled at 120 to 180°C.

[0012] cool down After the hot pressing is completed, the furniture wood parts are taken out of the heat curing equipment and sent to the cooling equipment for cooling. The purpose of cooling is to make the furniture wood parts semi-finished products gradually shrink in the process of temperature reduction, eliminate internal stress, and improve the dimensional stability of the furniture wood parts semi-finished products. The cooling method can be natural cooling or forced cooling (such as air cooling or water cooling). The cooling time depends on the specifications of the furniture wood parts semi-finished products and the cooling method, and is generally 1 to 2 hours.

[0013] Preferably, further processing of semi-finished wooden furniture parts: Raw material preparation Small wood particles: Screen out small wood particles with a diameter of 0.05mm to 0.1mm, remove impurities and particles that do not meet the particle size requirements, and ensure their purity and particle size uniformity; Raw materials for waterproof formaldehyde-free glue: prepare polyvinyl alcohol, acrylic emulsion, hydroxyethyl cellulose, silicone defoamer, deionized water, and benzotriazole raw materials, and check their quality and expiration date; Add deionized water into the reactor, start stirring, stir at a slow speed, and raise the temperature to 80 to 90°C.

[0014] Slowly add polyvinyl alcohol and continue stirring until it is completely dissolved to form a uniform solution. This process takes 30 to 60 minutes, depending on the dissolution of polyvinyl alcohol. After the solution is cooled to 50 to 60° C., add the acrylic emulsion and continue stirring for 30 to 45 minutes to fully mix the emulsion and the polyvinyl alcohol solution.

[0015] Adding additives Add hydroxyethyl cellulose, silicone defoamer and benzotriazole in sequence. When adding hydroxyethyl cellulose, add it slowly and stir continuously to prevent agglomeration. The stirring time is about 20 to 30 minutes to thicken the system and reach a suitable viscosity. Add silicone defoamer and stir for 10 to 15 minutes to eliminate bubbles in the system; Add benzotriazole and stir for 15 to 20 minutes to evenly disperse it in the system to provide UV protection; Add small wood pellets Slowly add the screened small wood particles into the mixed glue, and increase the stirring speed to a high-speed stirring state for about 45 to 60 minutes to ensure that the wood particles are evenly dispersed in the glue to form a wood particle coating; Quality inspection and adjustment Carry out quality inspection on the produced wood particle coating, including viscosity, solid content, and fineness index. If the viscosity does not meet the requirements, it can be adjusted by adding an appropriate amount of deionized water or thickener. If the fineness is not enough, it can be further ground using grinding equipment; Painting steps Stirring paint Before use, stir the wood particle coating again to ensure that the wood particles and glue are evenly mixed to avoid sedimentation or stratification; Test coating Carry out trial coating on a small area of ​​wooden furniture parts to observe the coating effect, drying time, and adhesion performance of the coating, and adjust the coating process parameters such as coating dilution, coating pressure, and coating speed according to the trial coating results; Official painting Spraying method: If you use a spray gun for painting, adjust the spray gun to the appropriate pressure and spray mode to spray the paint evenly on the surface of the furniture wood parts. The distance between the spray gun and the surface of the furniture wood parts is generally maintained at 20 to 30 cm. When spraying, move the spray gun at a uniform speed to avoid dripping and missing spraying. Generally, 2 to 3 sprayings are required. The interval between each spraying depends on the drying speed of the paint, usually 1 to 2 hours; Drying and curing After painting, place the wooden furniture pieces in a well-ventilated, dry environment for drying and curing. The drying time depends on the type of paint, ambient temperature and humidity factors, and generally takes 24 to 48 hours. During the drying process, the wooden furniture pieces need to be protected from collision, friction and contamination. Grinding and polishing If you need a finer, smoother surface, you can use sandpaper to lightly sand the surface of the wooden furniture after the paint is completely dry, and then polish it.

[0016] The beneficial effects of the present invention are: In this production process, a plastic skeleton is used as a skeleton to fill wood fillers, and the semi-finished wooden furniture parts have a similar feel to solid wood furniture. The fine wood powder coating forms a delicate shell on the outside, which has a good touch and can be comparable to precious solid wood. The wooden furniture parts produced using this process reduce material costs, and precise mixing allows the glue and particles to be tightly combined to enhance the strength of the coating; acrylic emulsion and benzotriazole give moisture-proof properties; thickeners and composite structures enhance deformation resistance, so that wooden furniture parts have a certain range of adaptability to environmental temperature and humidity, and can give full play to the coating's low density, high strength, formaldehyde-free, moisture-proof, and deformation-resistant advantages, and are suitable for a variety of scenarios.

[0017] The wooden furniture pieces produced in this production process can be molded into different structures by replacing different molds, so that the wooden furniture pieces can be assembled and combined with each other to form a complete piece of furniture. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of an example of wooden furniture pieces produced by a low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden process proposed by the present invention.

[0019] In the figure: 100, plastic frame; 200, wooden filler; 300, fine wood powder paint. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0021] Reference Figure 1 , a low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden craft, comprising a plastic frame 100, a wooden filler 200, and a fine rice powder coating 300; The plastic frame 100 specifically comprises: ‌ The content of polyamide resin is 80% to 85%, the content of glass fiber is 10% to 15%, and the content of calcium carbonate is 5% to 10% to form the basic cost of the plastic skeleton 100; Trace elements, one or more of copper elements such as cuprous iodide, cuprous bromide, cupric bromide, cuprous chloride, and cupric acetate, with the content of trace elements ranging from 0.02 to 0.2%; Enhancer, one or more of potassium bromide, sodium bromide, lithium bromide, calcium bromide, and magnesium bromide alkali metal, the content of the enhancer is 0.05 to 0.5%; The wood filler 200 specifically comprises: The wood filler 200 includes large wood particles and formaldehyde-free glue, and the mixing ratio W of the wood particles and the formaldehyde-free glue is 95:5; The diameter of large wood particles ranges from 3mm to 8mm; The ingredients of formaldehyde-free glue: polyvinyl alcohol 6% to 16%, BPA cross-linking agent 9% to 21%, YH1 complexing agent 14% to 16%, water 16% to 30%, oxidized starch 20% to 25%; Fine wood powder coating 300 specifically includes: Fine Wood Powder Paint 300 includes small-grain wood particles and waterproof formaldehyde-free glue; The diameter of small wood particles is between 0.05mm and 0.1mm; The ingredients of waterproof formaldehyde-free glue: polyvinyl alcohol 5%~10%, acrylic emulsion 30%~40%, hydroxyethyl cellulose 0.5%~1%, silicone defoamer 0.2%~1%, deionized water 30%~35%, and benzotriazole 0.5%~1%.

[0022] In an optional embodiment, the process comprises the following steps: Raw material pretreatment: Polyamide resin: Check the appearance of the polyamide resin to ensure that there are no impurities or lumps. If the resin has a high moisture content, it needs to be dried. Generally, it can be dried in a blast drying oven at 80 to 120°C for 4 to 8 hours to remove moisture and prevent bubble defects in subsequent processing; Glass fiber: Choose glass fiber of appropriate length and diameter, usually 3 to 6 mm in length, and treat the surface of the glass fiber. A coupling agent such as silane coupling agent can be used to enhance the interfacial bonding between the glass fiber and the polyamide resin. Soak the glass fiber in a diluted coupling agent solution and then dry it at 100 to 120°C. Calcium carbonate: Choose calcium carbonate with appropriate particle size, generally 1 to 10 μm. To improve the compatibility of calcium carbonate with resin, it can be surface modified and coated with stearic acid; Trace elements and enhancers: Ensure that the purity and particle size of trace elements and enhancers meet the requirements. If necessary, they can be ground to ensure uniform dispersion; Equipment preparation: high-speed mixer, twin-screw extruder, drying equipment, metering equipment; Initial mixing Measurement: According to the formula, accurately weigh 80% to 85% of polyamide resin, 10% to 15% of glass fiber, 5% to 10% of calcium carbonate, 0.02% to 0.2% of trace elements and 0.05% to 0.5% of reinforcing agent; Adding materials: Add the weighed polyamide resin into the high-speed mixer, start stirring, and control the stirring speed at 300 to 500 r / min; Add trace elements and enhancers: During the stirring process, slowly add trace elements and enhancers, and continue stirring for 5 to 10 minutes to make the trace elements and enhancers evenly dispersed in the polyamide resin; Add calcium carbonate: Then add the surface treated calcium carbonate and stir for 10 to 15 minutes to ensure that the calcium carbonate and resin are fully mixed; Add glass fiber: Finally, add the surface treated glass fiber. Since the glass fiber is long, add it slowly and evenly to avoid entanglement. Continue stirring for 15 to 20 minutes to evenly distribute the glass fiber in the mixture; Melt Blending Preheat the twin-screw extruder: Set the temperature of each heating zone of the twin-screw extruder to the melting temperature range of the polyamide resin, generally 220 to 280°C, and preheat so that the screw and barrel reach the set temperature and stabilize.

[0023] Feeding: The preliminarily mixed materials are evenly added into the hopper of the twin-screw extruder through the feeding device. The feeding speed should be adjusted according to the production capacity of the extruder and the screw speed, and is generally controlled at 10 to 30 kg / h.

[0024] Screw speed: Adjust the screw speed of the twin-screw extruder, generally 200 to 400r / min, so that the material can be fully melted, mixed and plasticized under the shearing and conveying action of the screw.

[0025] Shaping: After the materials are melt-blended in the extruder, they are injected into the mold and shaped into a plastic skeleton 100 with five-sided holes; Drying: The plastic skeleton 100 is placed in a forced air drying oven and dried at 80 to 120° C. for 4 to 8 hours to remove moisture and improve the storage stability of the product.

[0026] It should be noted that

[0027] In an optional embodiment, the plastic skeleton 100 is subjected to filler treatment: Raw material pretreatment Wood particles: Screen out large wood particles with a diameter of 3 to 8 mm, remove the bark, soil, sand and stone impurities mixed in them, and steam the wood to reduce the density of the wood material. To ensure the subsequent gluing effect, the wood particles can be dried to control the moisture content to 6% to 12%. It can be dried by natural airing or drying equipment. The drying temperature should not exceed 80°C to prevent the carbonization of the wood particles from affecting the performance of the wooden furniture parts.

[0028] Preparation of formaldehyde-free glue: According to the formula, accurately weigh 6% to 16% polyvinyl alcohol, 9% to 21% BPA crosslinker, 14% to 16% YH to 1 complexing agent, 16% to 30% water, and 20% to 25% oxidized starch. First, add water to the reactor and heat it to an appropriate temperature, generally 70 to 90°C, then slowly add polyvinyl alcohol and stir until it is completely dissolved. Then, add BPA crosslinker, YH to 1 complexing agent and oxidized starch in turn, continue stirring and control the reaction temperature and time to allow each component to react fully to make a uniform formaldehyde-free glue; Glue Mixing Add the pretreated wood particles into the drum glue mixer, start the glue mixer, and slowly add the formaldehyde-free glue into the glue mixer according to a certain ratio of glue to wood particles of 1:4 to 1:6 according to the weight of the wood particles. During the process of adding glue, continue to stir so that the glue is evenly attached to the surface of the wood particles. The stirring time is generally controlled at 5 to 15 minutes. The specific time can be adjusted according to the performance of the glue mixer and the state of the wood particles; Paving The wood particles mixed with glue, i.e., wood filler 200, are conveyed to the mold through a conveyor belt, and the mold is used to fill the wood particles into the pentagonal holes on the plastic frame 100; Heat curing It will be sent to the hot press for hot pressing. The hot pressing process is a key step in the molding of wooden furniture parts. The formaldehyde-free glue is solidified by heating and pressurizing, and the plastic frame 100 and the wooden filler 200 are molded together to form a semi-finished wooden furniture part. The hot pressing temperature is generally controlled at 120 to 180°C.

[0029] cool down After the hot pressing is completed, the furniture wood parts are taken out of the heat curing equipment and sent to the cooling equipment for cooling. The purpose of cooling is to make the furniture wood parts semi-finished products gradually shrink in the process of temperature reduction, eliminate internal stress, and improve the dimensional stability of the furniture wood parts semi-finished products. The cooling method can be natural cooling or forced cooling such as air cooling or water cooling. The cooling time depends on the specifications of the furniture wood parts semi-finished products and the cooling method, and is generally 1 to 2 hours.

[0030] It should be noted that larger wooden particles are mixed with glue and filled into the plastic frame 100, which can fill the voids of 100 and avoid a large difference between the use experience of wooden furniture parts and wood.

[0031] In an alternative embodiment, further processing of the semi-finished wooden furniture component: Raw material preparation Small wood particles: Screen out small wood particles with a diameter of 0.05mm to 0.1mm, remove impurities and particles that do not meet the particle size requirements, and ensure their purity and particle size uniformity; Raw materials for waterproof formaldehyde-free glue: prepare polyvinyl alcohol, acrylic emulsion, hydroxyethyl cellulose, silicone defoamer, deionized water, and benzotriazole raw materials, and check their quality and expiration date; Add deionized water into the reactor, start stirring, stir at a slow speed, and raise the temperature to 80 to 90°C.

[0032] Slowly add polyvinyl alcohol and continue stirring until it is completely dissolved to form a uniform solution. This process takes 30 to 60 minutes, depending on the dissolution of polyvinyl alcohol. After the solution is cooled to 50 to 60° C., add the acrylic emulsion and continue stirring for 30 to 45 minutes to fully mix the emulsion and the polyvinyl alcohol solution.

[0033] Adding additives Add hydroxyethyl cellulose, silicone defoamer and benzotriazole in sequence. When adding hydroxyethyl cellulose, add it slowly and stir continuously to prevent agglomeration. The stirring time is about 20 to 30 minutes to thicken the system and reach a suitable viscosity. Add silicone defoamer and stir for 10 to 15 minutes to eliminate bubbles in the system; Add benzotriazole and stir for 15 to 20 minutes to evenly disperse it in the system to provide UV protection; Add small wood pellets Slowly add the screened small wood particles into the mixed glue, and increase the stirring speed to a high-speed stirring state for about 45 to 60 minutes to ensure that the wood particles are evenly dispersed in the glue to form a wood particle coating; Quality inspection and adjustment Carry out quality inspection on the produced wood particle coating, including viscosity, solid content, and fineness index. If the viscosity does not meet the requirements, it can be adjusted by adding an appropriate amount of deionized water or thickener. If the fineness is not enough, it can be further ground using grinding equipment; Painting steps Stirring paint Before use, stir the wood particle coating again to ensure that the wood particles and glue are evenly mixed to avoid sedimentation or stratification; Test coating Carry out trial coating on a small area of ​​wooden furniture parts to observe the coating effect, drying time, and adhesion performance of the coating, and adjust the coating process parameters such as coating dilution, coating pressure, and coating speed according to the trial coating results; Official painting Spraying method: If you use a spray gun for painting, adjust the spray gun to the appropriate pressure and spray mode to spray the paint evenly on the surface of the furniture wood parts. The distance between the spray gun and the surface of the furniture wood parts is generally maintained at 20 to 30 cm. When spraying, move the spray gun at a uniform speed to avoid dripping and missing spraying. Generally, 2 to 3 sprayings are required. The interval between each spraying depends on the drying speed of the paint, usually 1 to 2 hours; Drying and curing After painting, place the wooden furniture pieces in a well-ventilated, dry environment for drying and curing. The drying time depends on the type of paint, ambient temperature and humidity factors, and generally takes 24 to 48 hours. During the drying process, the wooden furniture pieces need to be protected from collision, friction and contamination. Grinding and polishing If you need to get a more delicate and smooth surface effect, you can use sandpaper to lightly sand the surface of the wooden furniture after the paint is completely dry, and then polish it; In another embodiment, the wooden particles in the wooden filler 200 and the fine rice powder coating 300 may be replaced with bamboo particles, which can further reduce material costs and environmental protection.

[0034] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can replace or change the technical solution and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden product, characterized by: It includes a plastic frame (100), a wooden filler (200), and a fine rice powder coating (300); The plastic frame (100) specifically comprises: ‌ The content of polyamide resin is between 80% and 85%, the content of glass fiber is between 10% and 15%, and the content of calcium carbonate is between 5% and 10% to form the basic cost of the plastic skeleton (100); Trace elements, one or more of copper elements such as cuprous iodide, cuprous bromide, cupric bromide, cuprous chloride, and cupric acetate, with the content of trace elements ranging from 0.02 to 0.2%; Enhancer, one or more of potassium bromide, sodium bromide, lithium bromide, calcium bromide, and magnesium bromide alkali metal, the content of the enhancer is 0.05 to 0.5%; The wood filler (200) specifically includes: The wood filler (200) includes large wood particles and formaldehyde-free glue, and the mixing ratio W of the wood particles and the formaldehyde-free glue is 95:5; The diameter of large wood particles ranges from 3mm to 8mm; Ingredients of formaldehyde-free glue: polyvinyl alcohol 6% to 16%, BPA cross-linking agent 9% to 21%, YH1 complexing agent 14% to 16%, water 16% to 30%, oxidized starch 20% to 25%; Fine wood powder coating (300) specifically includes: Fine wood powder paint (300) includes small-grain wood particles and waterproof formaldehyde-free glue; The diameter of small wood particles is between 0.05mm and 0.1mm; The ingredients of waterproof formaldehyde-free glue: polyvinyl alcohol 5%~10%, acrylic emulsion 30%~40%, hydroxyethyl cellulose 0.5%~1%, silicone defoamer 0.2%~1%, deionized water 30%~35%, and benzotriazole 0.5%~1%.

2. A low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden craft according to claim 1, characterized in that: The process comprises the following steps; Raw material pretreatment: Polyamide resin: Check the appearance of the polyamide resin to ensure that there are no impurities or lumps. If the resin has a high moisture content, it needs to be dried. Generally, it can be dried in a blast drying oven at 80 to 120°C for 4 to 8 hours to remove moisture and prevent bubble defects in subsequent processing; Glass fiber: Select glass fiber of appropriate length and diameter, usually 3 to 6 mm in length, and treat the surface of the glass fiber. A coupling agent (such as silane coupling agent) may be used to enhance the interfacial bonding between the glass fiber and the polyamide resin. Soak the glass fiber in a diluted coupling agent solution and then dry it at 100 to 120°C. Calcium carbonate: Choose calcium carbonate with appropriate particle size, generally 1 to 10 μm. To improve the compatibility of calcium carbonate with resin, it can be surface modified and coated with stearic acid; Trace elements and enhancers: Ensure that the purity and particle size of trace elements and enhancers meet the requirements. If necessary, they can be ground to ensure uniform dispersion; Equipment preparation: high-speed mixer, twin-screw extruder, drying equipment, metering equipment; Initial mixing Measurement: Accurately weigh polyamide resin (80% to 85%), glass fiber (10% to 15%), calcium carbonate (5% to 10%), trace elements (0.02% to 0.2%) and reinforcing agent (0.05% to 0.5%) according to the formula; Adding materials: Add the weighed polyamide resin into the high-speed mixer, start stirring, and control the stirring speed at 300 to 500 r / min; Adding trace elements and enhancers: During the stirring process, slowly add the trace elements and enhancers, and continue stirring for 5 to 10 minutes to make the trace elements and enhancers evenly dispersed in the polyamide resin; Add calcium carbonate: Then add the surface treated calcium carbonate and stir for 10 to 15 minutes to ensure that the calcium carbonate and resin are fully mixed; Add glass fiber: Finally, add the surface treated glass fiber. Since the glass fiber is long, add it slowly and evenly to avoid entanglement. Continue stirring for 15 to 20 minutes to evenly distribute the glass fiber in the mixture; Melt Blending Preheat the twin-screw extruder: Set the temperature of each heating zone of the twin-screw extruder to the melting temperature range of the polyamide resin, generally 220 to 280°C, and preheat the screw and barrel to the set temperature and stabilize; Feeding: Add the preliminarily mixed materials evenly into the hopper of the twin-screw extruder through the feeding device. The feeding speed should be adjusted according to the production capacity of the extruder and the screw speed, and is generally controlled at 10 to 30 kg / h; Screw speed: adjust the screw speed of the twin-screw extruder, generally 200 to 400r / min, so that the material is fully melted, mixed and plasticized under the shearing and conveying action of the screw; Shaping: After the materials are melt-blended in the extruder, they are injected into a mold and shaped into a plastic skeleton (100) having five-sided holes; Drying: Place the plastic frame (100) in a forced air drying oven and dry it at 80 to 120°C for 4 to 8 hours to remove moisture and improve the storage stability of the product.

3. A low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden craft according to claim 2, characterized in that: For the plastic skeleton (100), filler treatment is performed: Raw material pretreatment Wood particles: Screen out large wood particles with a diameter of 3 to 8 mm, remove the bark, soil, sand and stone impurities mixed in them. In order to reduce the density of wood materials, the wood needs to be steamed. To ensure the subsequent gluing effect, the wood particles can be dried to control the moisture content to 6% to 12%. It can be dried by natural airing or drying equipment. The drying temperature should not exceed 80°C to prevent the carbonization of wood particles from affecting the performance of furniture wood parts; Preparation of formaldehyde-free glue: According to the formula, accurately weigh 6% to 16% polyvinyl alcohol, 9% to 21% BPA crosslinker, 14% to 16% YH to 1 complexing agent, 16% to 30% water, and 20% to 25% oxidized starch. First, add water to the reactor and heat it to an appropriate temperature (generally 70 to 90°C), then slowly add polyvinyl alcohol and stir until it is completely dissolved. Then, add BPA crosslinker, YH to 1 complexing agent and oxidized starch in turn, continue stirring and control the reaction temperature and time to allow each component to react fully to make a uniform formaldehyde-free glue; Glue Mixing Add the pretreated wood particles into the drum glue mixer, start the mixer, and slowly add the formaldehyde-free glue to the mixer according to a certain ratio (the mass ratio of glue to wood particles is 1:4 to 1:6) based on the weight of the wood particles. During the process of adding glue, continue to stir so that the glue is evenly attached to the surface of the wood particles. The stirring time is generally controlled at 5 to 15 minutes. The specific time can be adjusted according to the performance of the glue mixer and the state of the wood particles. Paving The wood particles mixed with glue, i.e. the wood filler (200), are conveyed to the mold via a conveyor belt, and the mold is used to fill the wood particles into the pentagonal holes on the plastic frame (100); Heat curing The plastic frame (100) and the wood filler (200) are molded together to form a semi-finished wooden furniture piece. The hot pressing temperature is generally controlled at 120 to 180°C. cool down After the hot pressing is completed, the furniture wood parts are taken out of the heat curing equipment and sent to the cooling equipment for cooling. The purpose of cooling is to make the furniture wood parts semi-finished products gradually shrink in the process of temperature reduction, eliminate internal stress, and improve the dimensional stability of the furniture wood parts semi-finished products. The cooling method can be natural cooling or forced cooling (such as air cooling or water cooling). The cooling time depends on the specifications of the furniture wood parts semi-finished products and the cooling method, and is generally 1 to 2 hours.

4. A low-density, high-strength, formaldehyde-free, moisture-proof and deformation-resistant wooden craft according to claim 3, characterized in that: Further processing of semi-finished wooden furniture parts: Raw material preparation Small wood particles: Screen out small wood particles with a diameter of 0.05mm to 0.1mm, remove impurities and particles that do not meet the particle size requirements, and ensure their purity and particle size uniformity; Raw materials for waterproof formaldehyde-free glue: prepare polyvinyl alcohol, acrylic emulsion, hydroxyethyl cellulose, silicone defoamer, deionized water, and benzotriazole raw materials, and check their quality and expiration date; Add deionized water to the reactor, start stirring, stir at a slow speed, and raise the temperature to 80 to 90°C; Slowly add polyvinyl alcohol and continue stirring until it is completely dissolved to form a uniform solution. This process takes 30 to 60 minutes, depending on the dissolution of polyvinyl alcohol. When the solution is cooled to 50 to 60°C, add the acrylic emulsion and continue stirring for 30 to 45 minutes to fully mix the emulsion and the polyvinyl alcohol solution; Adding additives Add hydroxyethyl cellulose, silicone defoamer and benzotriazole in sequence. When adding hydroxyethyl cellulose, add it slowly and stir continuously to prevent agglomeration. The stirring time is about 20 to 30 minutes to thicken the system and reach a suitable viscosity. Add silicone defoamer and stir for 10 to 15 minutes to eliminate bubbles in the system; Add benzotriazole and stir for 15 to 20 minutes to evenly disperse it in the system to provide UV protection; Add small wood pellets Slowly add the screened small wood particles into the mixed glue, and increase the stirring speed to a high-speed stirring state for about 45 to 60 minutes to ensure that the wood particles are evenly dispersed in the glue to form a wood particle coating; Quality inspection and adjustment Carry out quality inspection on the produced wood particle coating, including viscosity, solid content, and fineness index. If the viscosity does not meet the requirements, it can be adjusted by adding an appropriate amount of deionized water or thickener. If the fineness is not enough, it can be further ground using grinding equipment; Painting steps Stirring paint Before use, stir the wood particle coating again to ensure that the wood particles and glue are evenly mixed to avoid sedimentation or stratification; Test coating Carry out trial coating on a small area of ​​wooden furniture parts to observe the coating effect, drying time, and adhesion performance of the coating, and adjust the coating process parameters such as coating dilution, coating pressure, and coating speed according to the trial coating results; Official painting Spraying method: If you use a spray gun for painting, adjust the spray gun to the appropriate pressure and spray mode to spray the paint evenly on the surface of the furniture wood parts. The distance between the spray gun and the surface of the furniture wood parts is generally maintained at 20 to 30 cm. When spraying, move the spray gun at a uniform speed to avoid dripping and missing spraying. Generally, 2 to 3 sprayings are required. The interval between each spraying depends on the drying speed of the paint, usually 1 to 2 hours; Drying and curing After painting, place the wooden furniture pieces in a well-ventilated, dry environment for drying and curing. The drying time depends on the type of paint, ambient temperature and humidity factors, and generally takes 24 to 48 hours. During the drying process, the wooden furniture pieces need to be protected from collision, friction and contamination. Grinding and polishing If you need a finer, smoother surface, you can use sandpaper to lightly sand the surface of the wooden furniture after the paint is completely dry, and then polish it.

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