Environment-friendly solid wood floor adopting deep carbonization treatment process and production method of environment-friendly solid wood floor

Abstract

According to the environment-friendly solid wood floor adopting the deep carbonization treatment process and the production method of the environment-friendly solid wood floor, modification of a wood molecular structure is achieved through the steps of raw wood material pretreatment, high-temperature and high-pressure deep carbonization treatment, cooling stabilization treatment, surface waterproof treatment, standard floor processing and the like. According to the method, deep pyrolysis treatment is conducted in the high-temperature environment of 190-212 DEG C, the hemicellulose structure of the wood is changed from the molecular level, chemical agents do not need to be added, release of harmful substances such as formaldehyde is thoroughly eliminated, and meanwhile the size stability and corrosion resistance of the wood are remarkably improved. The perfect combination of the natural attractiveness of the traditional solid wood floor and the stability of the modern technology is realized, and an innovative solution is provided for green building materials.

Description

Technical Field

[0001] This invention relates to the field of wood processing technology, and in particular to an environmentally friendly solid wood flooring using a deep carbonization process and its production method. Background Technology

[0002] Solid wood flooring, as a green and environmentally friendly decorative material, occupies an important position in the modern home decoration market. Traditional solid wood flooring has advantages such as natural beauty, comfortable feel, and recyclability, but it also faces technical challenges such as poor dimensional stability, susceptibility to moisture and deformation, and the need for chemical preservative treatment. With people's increasing demands for indoor environmental quality, developing new solid wood flooring technologies that retain the natural characteristics of solid wood while overcoming traditional defects is of great significance.

[0003] Currently, the most common methods for stabilizing solid wood flooring on the market include chemical impregnation and hot-press modification. Chemical impregnation improves wood properties by injecting preservatives, stabilizers, and other chemicals into the wood, while hot-press modification enhances the dimensional stability of the wood through physical changes under high temperature and high pressure conditions.

[0004] The most closely related prior art to this invention is a composite modification process combining chemical agents and heat treatment. This technology first pre-impregnates the wood with chemical fillers such as formaldehyde resin and melamine resin, then heat-cures it at 120℃-150℃. Through chemical cross-linking and moderate heat modification, the dimensional stability and anti-corrosion properties of the wood are improved. The technical principle is to use chemical fillers to fill the voids in the wood cell walls, while simultaneously using moderate-temperature heat treatment to cure the fillers and slightly modify the wood fibers.

[0005] However, the aforementioned existing technologies have two key technical problems: First, the use of chemical agents leads to the continuous release of harmful substances such as formaldehyde, which seriously affects indoor air quality and human health; second, medium-temperature heat treatment cannot fundamentally change the molecular structure of wood hemicellulose, and its effect on improving the swelling and shrinkage properties of wood is limited, making it difficult to meet the strict requirements for dimensional stability in high-end application scenarios. Summary of the Invention

[0006] The purpose of this invention is to provide an environmentally friendly solid wood flooring using a deep carbonization process and its production method, aiming to solve the technical problems of poor dimensional stability and release of harmful substances caused by chemical treatment in existing solid wood flooring.

[0007] To achieve the above objectives, the present invention provides a method for producing environmentally friendly solid wood flooring using a deep carbonization process, comprising the following steps:

[0008] The raw wood material is obtained, and the moisture content of the wood is controlled within the range of 8%-12% through natural drying or low-temperature drying. Surface impurities are removed using cleaning equipment, and the wood is cut to standard specifications and inspected for quality to obtain pre-treated qualified wood.

[0009] The pre-treated wood is placed in a special reactor according to the specified loading method. The temperature of the reactor is raised to 190℃-212℃ at a heating rate of 15℃-20℃ per hour and maintained at a constant temperature for 2-4 hours. Through the action of high temperature, the hemicellulose and some cell wall components in the wood undergo a pyrolysis reaction to obtain wood that has undergone deep carbonization treatment.

[0010] Turn off the heating system and reduce the temperature of the reactor to below 60°C at a cooling rate of 10°C-15°C per hour. Turn on the ventilation system to accelerate cooling and remove the reaction gas. Take out the wood after deep carbonization treatment and place it in a constant temperature and humidity environment for 48-72 hours of stabilization curing to obtain carbonized wood after stabilization treatment.

[0011] The carbonized wood after stabilization treatment is finely sanded using sanding equipment, and a water-based waterproof coating is prepared and evenly applied to the wood surface using a multi-layer thin-coat process to obtain the waterproof carbonized wood.

[0012] The carbonized wood that has undergone waterproofing treatment is precisely cut into standard-sized floor strips according to flooring product standards, and then tongue and groove processing and final quality inspection are carried out to obtain environmentally friendly solid wood flooring products.

[0013] Further, the log material is pretreated to obtain pretreated and qualified wood, including:

[0014] Based on the aforementioned log material, the moisture content is precisely controlled using natural drying or low-temperature drying processes, so that the wood moisture content reaches the range of 8%-12%.

[0015] For wood with a moisture content in the range of 8%-12%, use specialized cleaning equipment to remove surface dust, grease and other impurities to obtain clean wood.

[0016] The cleaned wood is cut into standard sizes suitable for reactor processing, and quality inspection is performed to remove obvious defects, thus obtaining the pre-treated qualified wood.

[0017] Furthermore, the carbonization temperature of 190℃-212℃ is set differently according to the type of wood, with hardwoods using a temperature range of 195℃-212℃ and softwoods using a temperature range of 190℃-205℃.

[0018] Furthermore, during the deep carbonization process, based on the pretreated and qualified wood, an appropriate amount of steam is injected to maintain the humidity environment inside the reactor to prevent the wood from cracking due to excessive dehydration. At the same time, the temperature, pressure and humidity parameters during the reaction process are monitored to obtain the wood after deep carbonization.

[0019] Furthermore, the deeply carbonized wood is removed and placed in a constant temperature and humidity environment for 48-72 hours for stabilization curing to obtain stabilized carbonized wood, including:

[0020] Based on the wood after deep carbonization treatment, the heating system is turned off and the temperature of the reactor is gradually reduced at a cooling rate of 10℃-15℃ per hour, so that the temperature drops steadily to below 60℃.

[0021] When the temperature of the reactor drops below 60°C, the ventilation system is turned on to accelerate the cooling process and remove the gas produced by the reaction, thus obtaining carbonized wood after cooling and exhaust treatment.

[0022] The carbonized wood after cooling and venting treatment is taken out of the reactor and placed in a constant temperature and humidity environment for 48-72 hours for stabilization curing to obtain the stabilized carbonized wood.

[0023] Furthermore, based on the carbonized wood after the stabilization treatment, the carbonized layer is removed by fine sanding using sanding equipment. A water-based waterproof coating without formaldehyde and other harmful substances is prepared and uniformly applied to the wood surface using a multi-layer thin-coat process and then fully dried to obtain the carbonized wood after the waterproof treatment.

[0024] Furthermore, a carbonization temperature correction formula was established based on wood density and cellulose content. Carbonization temperatures were set separately for hardwoods and softwoods, and the carbonization time was adjusted according to the initial moisture content of the wood. For wood with higher moisture content, the treatment time was extended by 30-60 minutes.

[0025] Furthermore, the deep carbonization process employs a staged temperature control process, including:

[0026] After loading the pretreated wood into a special reactor, the temperature of the reactor is raised to the first stage temperature of 160℃-180℃ at a heating rate of 15℃-20℃ per hour, and maintained for 1-2 hours for pre-carbonization treatment to obtain pre-carbonized wood.

[0027] The pre-carbonized wood is further heated to the second stage temperature of 190℃-212℃ and maintained for 2-4 hours for deep carbonization treatment, so that the hemicellulose and some cell wall components in the wood undergo a full pyrolysis reaction to obtain the wood after deep carbonization treatment.

[0028] Furthermore, the method also includes adding a surface modification treatment during the stabilization curing process, including:

[0029] Based on the carbonized wood after the stabilization treatment, a special equipment is used to treat the surface carbonization layer. The loose carbonization layer is removed by light sanding to obtain the surface-treated carbonized wood.

[0030] The carbonized wood after surface treatment is subjected to natural plant oil penetration treatment, which allows the plant oil to penetrate deep into the wood fibers to enhance stability, resulting in carbonized wood after penetration modification.

[0031] The carbonized wood that has undergone permeation modification is allowed to dry naturally for 24-48 hours to allow the plant oil to fully solidify and combine with the wood fibers, resulting in modified and stable carbonized wood, which is then used as the input material for the waterproofing treatment step.

[0032] Furthermore, after the environmentally friendly solid wood flooring product is manufactured, quality control is carried out before packaging, including:

[0033] Based on the aforementioned environmentally friendly solid wood flooring product, physical performance tests are conducted, including bending strength, impact toughness, and surface hardness testing, to obtain flooring products that meet physical performance standards.

[0034] Environmental performance testing is conducted on the flooring products that meet the physical performance requirements, including formaldehyde emission, heavy metal content, and VOC volatile organic compound testing, to obtain flooring products that meet environmental performance requirements.

[0035] The environmentally friendly flooring products that meet the required standards are graded and packaged according to different specifications and color differences, and product quality inspection reports and environmental certification marks are attached to obtain the final environmentally friendly solid wood flooring products.

[0036] An environmentally friendly solid wood flooring made using a deep carbonization process, employing the method described above.

[0037] The beneficial effects of this invention are:

[0038] By employing a high-temperature deep carbonization process of 190℃-212℃, the hemicellulose structure of wood is altered at the molecular level, resulting in a fundamental improvement in dimensional stability.

[0039] The purely physical modification process requires no chemical additives, completely eliminating the release of harmful substances such as formaldehyde and ensuring the environmental performance of the product.

[0040] Develop a specialized surface waterproofing treatment technology to effectively mitigate the impact of moisture on carbonized wood and further extend the lifespan of the flooring;

[0041] Establish a complete temperature, time, and humidity control system to ensure the consistency and stability of carbonization treatment results;

[0042] This achieves a perfect combination of the natural beauty of traditional solid wood flooring and the stability of modern technology, providing innovative solutions for green building materials. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a process flow diagram of an environmentally friendly solid wood flooring production method using a deep carbonization process according to the present invention.

[0045] Figure 2 This is a flowchart illustrating the pretreatment process of the log material according to the present invention.

[0046] Figure 3 This is a flowchart illustrating the stabilization process of carbonized wood according to the present invention. Detailed Implementation

[0047] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0048] In some of the processes described in the specification, claims, and accompanying drawings of this application, multiple operations appearing in a specific order are included. However, it should be clearly understood that these operations may not be executed in the order they appear herein, or may be executed in parallel. The operation numbers, such as S1, S2, etc., are merely used to distinguish different operations and do not themselves represent any execution order. Furthermore, these processes may include more or fewer operations, and these operations may be executed sequentially or in parallel. It should be noted that the descriptions such as "first," "second," etc., in this document are used to distinguish different messages, devices, modules, etc., and do not represent a sequential order, nor do they limit "first" and "second" to different types.

[0049] It will be understood by those skilled in the art that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this application’s specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein may include wireless connections or wireless coupling. The term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.

[0050] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have a meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0051] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Throughout the description, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0052] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0053] Example 1

[0054] like Figure 1 As shown, a method for producing environmentally friendly solid wood flooring using a deep carbonization process includes the following steps:

[0055] S1 obtains raw wood materials, controls the moisture content of the wood to the range of 8%-12% through natural drying or low-temperature drying, removes surface impurities using cleaning equipment, and performs standardized cutting and quality inspection to obtain pre-treated qualified wood.

[0056] Pre-treatment of raw timber is the foundation of the entire production process. Precise control of moisture content and surface cleanliness creates ideal conditions for subsequent carbonization. Maintaining a moisture content between 8% and 12% ensures appropriate moisture levels during carbonization, guaranteeing efficient heat transfer while preventing excessive drying that could lead to cracking. Removing surface impurities prevents them from undergoing chemical reactions at high temperatures that could negatively impact carbonization quality. Standardized cutting and quality inspection ensure that the raw materials entering the carbonization process are of suitable size and free of significant defects.

[0057] S2 The pre-treated qualified wood is placed in a special reactor according to the specified loading method. The temperature of the reactor is raised to 190℃-212℃ at a heating rate of 15℃-20℃ per hour and maintained at a constant temperature for 2-4 hours. Through the action of high temperature, the hemicellulose and some cell wall components in the wood undergo a pyrolysis reaction to obtain wood after deep carbonization treatment.

[0058] Deep carbonization is the core process of this invention. High temperatures of 190℃-212℃ are used to destroy the nutrients in the wood and restructure the hemicellulose molecular structure. The heating rate is controlled at 15℃-20℃ per hour to ensure a uniform temperature rise throughout the wood, preventing stress concentration and cracking due to excessive temperature gradients. Maintaining a constant temperature for 2-4 hours ensures the pyrolysis reaction proceeds fully, causing thorough structural changes in hemicellulose and some cell wall components, thereby fundamentally improving dimensional stability.

[0059] S3 shuts off the heating system and lowers the temperature of the reactor to below 60°C at a cooling rate of 10°C-15°C per hour. Then, it turns on the ventilation system to accelerate cooling and remove the reaction gas. The wood after deep carbonization is taken out and placed in a constant temperature and humidity environment for 48-72 hours of stabilization curing to obtain carbonized wood after stabilization treatment.

[0060] The modified molecular structure is stabilized and solidified by controlling the cooling rate and subsequent curing process. The cooling rate is controlled at 10-15°C per hour to prevent sudden temperature drops that could cause the wood to crack. When the temperature drops below 60°C, the ventilation system is activated to accelerate the cooling process and remove gases produced during the reaction. A constant temperature and humidity curing period of 48-72 hours allows for the full release of internal stress in the wood, ensuring dimensional stability and structural integrity.

[0061] S4 uses sanding equipment to finely polish the surface of the stabilized carbonized wood, prepares water-based waterproof coating and applies it evenly to the surface of the wood using a multi-layer thin coating process to obtain waterproof carbonized wood.

[0062] The loose carbonized layer on the surface is removed by sanding, and an effective moisture barrier is formed by applying a water-based waterproof coating. Sanding not only removes the surface carbonized layer formed during the carbonization process but also exposes the uniformly modified wood within, providing a good foundation for coating. Multiple thin coats ensure that the waterproof coating penetrates evenly and forms a continuous protective film, effectively mitigating the impact of moisture on the carbonized wood.

[0063] S5 involves precisely cutting and processing the waterproofed carbonized wood into standard-sized floor strips according to flooring product standards, performing tongue-and-groove processing, and conducting final quality inspection to obtain environmentally friendly solid wood flooring products.

[0064] Standard flooring processing is the process of transforming waterproofed carbonized wood into the final product, including precision cutting, tongue and groove machining, and quality inspection. Precision cutting ensures accurate floorboard dimensions, while tongue and groove machining guarantees a tight connection after installation. Final quality inspection includes key indicators such as dimensional accuracy, surface quality, moisture content, and formaldehyde emission levels to ensure the product meets all technical requirements for environmentally friendly solid wood flooring.

[0065] Example 2:

[0066] like Figure 2 As shown, the log material is pretreated to obtain pretreated and qualified wood, including:

[0067] S1.1 Based on the aforementioned log material, the moisture content is precisely controlled using natural drying or low-temperature drying processes to achieve a wood moisture content in the range of 8%-12%.

[0068] Precisely controlling the moisture content using natural drying or low-temperature drying processes is the first step in pretreatment. Different wood species require different drying methods. Natural drying is suitable when time is ample, allowing the moisture content to naturally decrease to the target range by stacking the wood in a well-ventilated environment. Low-temperature drying is suitable for time-sensitive production needs, involving slow drying at a controlled temperature between 40℃ and 60℃ to prevent the wood from cracking due to high temperatures. Moisture content is measured using a resistance moisture meter, taking samples from different locations on the wood to ensure uniform moisture content within the range of 8%-12%.

[0069] S1.2 For the wood with a moisture content in the range of 8%-12%, use special cleaning equipment to remove surface dust, grease and other impurities to obtain clean wood.

[0070] Removing surface impurities using specialized cleaning equipment is a crucial step in ensuring the quality of carbonization. This equipment includes a high-pressure airflow dust collector and a specialized surface cleaner. The high-pressure airflow effectively removes dust and loose impurities from the wood surface, while the specialized cleaner removes grease and other stubborn contaminants. The cleaned wood surface should be free of visible dust, grease, and other impurities to prevent adverse reactions during carbonization.

[0071] S1.3 The clean wood is cut into standard sizes suitable for reactor processing, and quality inspection is performed to remove obvious defects, thus obtaining the pre-treated qualified wood.

[0072] Standardized cutting and quality inspection are the final steps in the pretreatment process. Standardized cutting involves processing the wood into standard sizes suitable for the processing vessel, typically not exceeding 2.5 meters in length, 20 centimeters in width, and 5 centimeters in thickness. Quality inspection mainly targets defects such as knots, cracks, and decay in the wood. Wood with obvious defects is removed through visual inspection and specialized testing equipment to ensure that the raw materials entering the carbonization process meet quality standards.

[0073] Example 3:

[0074] The carbonization temperature of 190℃-212℃ is set differently according to the type of wood, with hardwoods using a temperature range of 195℃-212℃ and softwoods using a temperature range of 190℃-205℃.

[0075] Differentiated temperature settings based on wood species are key to improving carbonization results. Hardwoods such as oak, maple, and walnut, due to their high fiber density and compact structure, require a higher temperature range of 195℃-212℃ for carbonization to ensure sufficient heat penetration and complete pyrolysis of hemicellulose and some cell wall components. Softwoods such as pine, fir, and spruce, with their lower fiber density and looser structure, can achieve ideal carbonization results with a relatively lower temperature range of 190℃-205℃. Excessively high temperatures can lead to over-carbonization of softwoods, reducing their mechanical strength.

[0076] Example 4:

[0077] During the deep carbonization process, based on the pretreated and qualified wood, an appropriate amount of steam is injected to maintain the humidity environment inside the reactor to prevent the wood from cracking due to excessive dehydration. At the same time, the temperature, pressure and humidity parameters during the reaction process are monitored to obtain the wood after deep carbonization.

[0078] Maintaining a suitable humidity environment within the reactor by injecting an appropriate amount of steam is an effective measure to prevent wood from cracking. During carbonization, high temperatures cause the moisture in the wood to evaporate rapidly. If the humidity environment is not controlled, the wood is prone to cracking due to excessive dehydration. The steam injection system automatically adjusts the steam injection volume based on real-time humidity data within the reactor, maintaining the relative humidity within the reactor within the range of 15%-25%. This prevents excessive dehydration of the wood without affecting the carbonization reaction.

[0079] Monitoring temperature, pressure, and humidity parameters during the reaction process is crucial for ensuring carbonization quality. Temperature monitoring employs multiple temperature sensors distributed across different locations within the reactor to monitor temperature distribution in real time, ensuring temperature uniformity. Pressure monitoring uses pressure sensors to detect pressure changes within the reactor in real time, automatically activating the pressure relief system when the pressure exceeds a safe threshold. Humidity monitoring uses humidity sensors to detect the relative humidity within the reactor, providing data support for the steam injection system. These parameter data are recorded and analyzed through a central control system, forming complete process parameter curves that provide a basis for quality control and process optimization.

[0080] Example 5:

[0081] like Figure 3 As shown, the wood after deep carbonization is removed and placed in a constant temperature and humidity environment for 48-72 hours for stabilization curing to obtain stabilized carbonized wood, including:

[0082] S3.1 Based on the wood after deep carbonization treatment, turn off the heating system and gradually reduce the temperature of the reactor at a cooling rate of 10℃-15℃ per hour, so that the temperature drops steadily to below 60℃.

[0083] Gradually reducing the reactor temperature at a rate of 10°C-15°C per hour is crucial to prevent stress cracking in wood caused by sudden temperature drops. After carbonization, the wood exhibits a significant temperature difference between its internal and external surfaces. If the temperature drops too quickly, the surface and interior of the wood will shrink unevenly, leading to stress concentration and cracking. Controlling the cooling rate within the range of 10°C-15°C per hour ensures a uniform temperature decrease, reduces internal stress, and maintains the structural integrity of the wood.

[0084] S3.2 When the temperature of the reactor drops below 60°C, the ventilation system is turned on to accelerate the cooling process and remove the gas produced by the reaction, so as to obtain carbonized wood after cooling and exhaust treatment;

[0085] Turning on the ventilation system when the reactor temperature drops below 60°C is a crucial step for safe and efficient cooling. 60°C is a safe threshold; at this point, the wood surface temperature has decreased to a level that will not cause significant thermal stress, allowing for accelerated cooling. The ventilation system, through forced air circulation, not only speeds up heat dissipation but also removes volatile gases produced during carbonization, such as acetic acid and methanol, reducing their potential harm to the environment and human health.

[0086] S3.3 The carbonized wood after cooling and venting treatment is taken out of the reactor and placed in a constant temperature and humidity environment for 48-72 hours for stabilization curing to obtain the stabilized carbonized wood.

[0087] The final step in ensuring the carbonization effect is to place the carbonized wood, after cooling and degassing, in a constant temperature and humidity environment for 48-72 hours for stabilization. Stabilization is carried out in a constant temperature and humidity chamber at 20℃±2℃ and 50%±5% relative humidity, conditions close to the normal use environment of solid wood flooring. Under these conditions, residual stress within the carbonized wood is fully released, the modified molecular structure tends to stabilize, and the moisture content reaches equilibrium. The 48-72 hour stabilization time depends on the type of wood and the degree of carbonization; hardwoods and woods with a higher degree of carbonization require a longer stabilization time.

[0088] Example 6:

[0089] Based on the carbonized wood after the stabilization treatment, the carbonized layer is removed by fine sanding using sanding equipment. A water-based waterproof coating without formaldehyde and other harmful substances is prepared and evenly applied to the wood surface using a multi-layer thin-coat process and allowed to dry fully to obtain the carbonized wood after the waterproof treatment.

[0090] Removing the carbonized layer through fine sanding is the first step in surface waterproofing. During carbonization, a relatively loose carbonized layer forms on the wood surface. This layer is dark in color and structurally unstable, hindering the adhesion and penetration of subsequent coatings. Sanding employs a multi-grit sandpaper approach, first using 80-120 grit sandpaper to remove the loose carbonized layer, then medium sanding with 150-180 grit sandpaper, and finally fine sanding with 220-240 grit sandpaper to expose the uniformly modified wood within, providing a smooth and even base surface for coating.

[0091] Formulating formaldehyde-free and other harmful substances-free water-based waterproof coatings is crucial to ensuring the product's environmental performance. Water-based waterproof coatings consist of water-based acrylic resin, nano-silica, waterproofing additives, and water, and contain no formaldehyde, benzene, or other harmful substances. The water-based acrylic resin provides excellent adhesion and film-forming properties, the nano-silica enhances the coating's hardness and abrasion resistance, the waterproofing additives improve the coating's waterproof performance, and water acts as a solvent to ensure the coating's environmental friendliness and ease of application. Strict control of the component ratios is essential during coating formulation to ensure its stability and waterproofing effect.

[0092] Applying a multi-coat, thin-coat process evenly to the wood surface and allowing it to dry fully is crucial for forming a high-quality waterproof layer. This process typically involves 3-4 coats, each 30-50 micrometers thick, with a total thickness not exceeding 200 micrometers. The first coat acts as a primer, primarily penetrating the wood and enhancing adhesion; the second and third coats act as intermediate coats, providing waterproofing and filling; and the final coat acts as a topcoat, providing surface gloss and protection. After each coat, it needs to be dried for 4-6 hours at 20℃±2℃ and 60%±5% relative humidity to ensure full curing. Following all coats, a final curing period of 24-48 hours is required to allow the waterproof coating to reach its optimal performance.

[0093] Example 7:

[0094] A carbonization temperature correction formula was established based on wood density and cellulose content. Carbonization temperatures were set separately for hardwoods and softwoods, and the carbonization time was adjusted according to the initial moisture content of the wood. For wood with higher moisture content, the treatment time was extended by 30-60 minutes.

[0095] Establishing a carbonization temperature correction formula based on wood density and cellulose content is a scientific method for achieving precise carbonization. The correction formula is: T = T0 + k1(ρ - ρ0) + k2(C - C0), where T is the actual carbonization temperature, T0 is the reference temperature (200℃ for hardwood, 195℃ for softwood), ρ is the wood density, ρ0 is the reference density (0.7 g / cm³ for hardwood, 0.5 g / cm³ for softwood), C is the cellulose content, C0 is the reference cellulose content (45%), and k1 and k2 are the density correction coefficient and cellulose content correction coefficient, respectively. Using this formula, the optimal carbonization temperature can be accurately calculated based on the specific characteristics of different types of wood, ensuring consistent carbonization results.

[0096] Adjusting the carbonization time according to the initial moisture content of the wood is an important measure to ensure sufficient carbonization. Wood with higher moisture content requires a longer processing time because some heat energy is used for moisture evaporation, reducing the effective energy available for wood pyrolysis. The adjustment formula is: t = t0 + k3(M - M0), where t is the actual carbonization time, t0 is the baseline time (3 hours), M is the initial moisture content of the wood, M0 is the baseline moisture content (10%), and k3 is the moisture content correction factor (usually 10-15 minutes / 1% moisture content). When the wood moisture content is higher than the baseline value, the carbonization time should be extended by 10-15 minutes for every 1% increase; when the moisture content is lower than the baseline value, the carbonization time can be appropriately shortened, but it is not recommended to be less than 2 hours to ensure that the carbonization reaction proceeds fully.

[0097] Example 8:

[0098] The deep carbonization process employs a staged temperature control process, including:

[0099] After loading the pretreated wood into a special reactor, the temperature of the reactor is raised to the first stage temperature of 160℃-180℃ at a heating rate of 15℃-20℃ per hour, and maintained for 1-2 hours for pre-carbonization treatment to obtain pre-carbonized wood.

[0100] Raising the reactor temperature to the first-stage temperature of 160℃-180℃ at a heating rate of 15℃-20℃ per hour and maintaining this temperature for 1-2 hours for pre-carbonization is a crucial step in achieving stable carbonization. The main purpose of the pre-carbonization stage is to allow the wood to gradually adapt to the high-temperature environment, reducing the risk of cracking that may occur if the temperature is directly raised to high levels. Within the 160℃-180℃ temperature range, the free water and some bound water in the wood completely evaporate, and hemicellulose begins to undergo slight degradation, but has not yet reached the point of large-scale pyrolysis. Maintaining the pre-carbonization time for 1-2 hours allows the internal temperature distribution of the wood to become more uniform, creating favorable conditions for subsequent deep carbonization. The pre-carbonization time is determined based on the thickness and density of the wood; thicker and denser woods require a longer pre-carbonization time.

[0101] The pre-carbonized wood is further heated to the second stage temperature of 190℃-212℃ and maintained for 2-4 hours for deep carbonization treatment, so that the hemicellulose and some cell wall components in the wood undergo a full pyrolysis reaction to obtain the wood after deep carbonization treatment.

[0102] The core step in modifying the molecular structure of pre-carbonized wood is to further heat it to the second stage temperature of 190℃-212℃ and maintain this temperature for 2-4 hours for deep carbonization. Within this high-temperature range of 190℃-212℃, hemicellulose in the wood undergoes large-scale pyrolysis, destroying hydrophilic groups such as hydroxyl groups and forming new hydrophobic molecular structures. Furthermore, some cell wall components also undergo thermal degradation and reorganization, further reducing the wood's hygroscopicity and its properties of swelling and shrinking with moisture. Maintaining deep carbonization for 2-4 hours ensures the pyrolysis reaction proceeds fully, allowing the wood to achieve the desired modification effect from the inside out. The specific carbonization time is determined based on the wood species, density, and target degree of carbonization; generally, hardwoods require longer carbonization times, while softwoods require relatively shorter times.

[0103] Example 9:

[0104] The method further includes adding a surface modification treatment during the stabilization curing process, including:

[0105] Based on the carbonized wood after the stabilization treatment, a special equipment is used to treat the surface carbonization layer. The loose carbonization layer is removed by light sanding to obtain the surface-treated carbonized wood.

[0106] The first step in surface modification is to use specialized equipment to treat the surface carbonized layer, removing the loose carbonized layer through light sanding. During carbonization, a relatively loose carbonized layer forms on the wood surface. This carbonized material not only affects the appearance of the wood but may also affect the effectiveness of subsequent treatments. The surface carbonized layer treatment uses specialized sanding equipment with 100-120 grit sandpaper for light sanding, removing only the loose carbonized layer while preserving the stable carbonized wood components. The sanding process requires careful control of pressure and speed to avoid over-removal, which could lead to an uneven wood surface or damage to the wood structure.

[0107] The carbonized wood after surface treatment is subjected to natural plant oil penetration treatment, which allows the plant oil to penetrate deep into the wood fibers to enhance stability, resulting in carbonized wood after penetration modification.

[0108] Applying natural plant oils to carbonized wood after surface treatment is an effective way to enhance its stability. The main natural plant oils used are linseed oil and castor oil, which have good penetrating and oxidative curing properties. These oils are free of harmful substances and meet environmental protection requirements. The penetrating treatment uses dipping or spraying methods to ensure the plant oil evenly covers the wood surface and gradually penetrates into the wood fibers. The plant oil molecules fill the tiny gaps in the wood cell walls, forming a stable bond with the wood fibers, further reducing the wood's hygroscopicity and its tendency to expand and shrink with moisture.

[0109] The carbonized wood that has undergone permeation modification is allowed to dry naturally for 24-48 hours to allow the plant oil to fully solidify and combine with the wood fibers, resulting in modified and stable carbonized wood, which is then used as the input material for the waterproofing treatment step.

[0110] The key to ensuring the modification effect is to allow the carbonized wood, after infiltration modification, to air dry naturally for 24-48 hours, allowing the plant oil to fully solidify and bond with the wood fibers. Natural drying should be carried out in an environment with a temperature of 20℃±2℃ and a relative humidity of 50%±5%, avoiding direct sunlight and strong winds. During the drying process, the unsaturated fatty acids in the plant oil react with oxygen in the air to form a network cross-linked structure, achieving the curing process. The drying time depends on the type and amount of plant oil used; generally, linseed oil requires a shorter drying time (24-36 hours), while castor oil requires a longer time (36-48 hours). After drying, the wood surface should have no obvious greasy feel, and no oil residue should remain when touched, indicating that the plant oil has fully solidified.

[0111] Example 10:

[0112] Quality control before packaging is performed after the environmentally friendly solid wood flooring product is manufactured, including:

[0113] Based on the aforementioned environmentally friendly solid wood flooring product, physical performance tests are conducted, including bending strength, impact toughness, and surface hardness testing, to obtain flooring products that meet physical performance standards.

[0114] Environmental performance testing is conducted on the flooring products that meet the physical performance requirements, including formaldehyde emission, heavy metal content, and VOC volatile organic compound testing, to obtain flooring products that meet environmental performance requirements.

[0115] The environmentally friendly flooring products that meet the required standards are graded and packaged according to different specifications and color differences, and product quality inspection reports and environmental certification marks are attached to obtain the final environmentally friendly solid wood flooring products.

[0116] Conducting physical performance tests, including flexural strength, impact toughness, and surface hardness testing, is a crucial step in ensuring the performance of flooring. The flexural strength test uses the three-point bending method, conducted according to GB / T 17657 standard, requiring a flexural strength of no less than 80% of that of the original wood. The impact toughness test uses the pendulum impact method, conducted according to GB / T 1043 standard, requiring an impact toughness of no less than 75% of that of the original wood. The surface hardness test uses the Brinell hardness method, conducted according to GB / T 1941 standard, requiring a surface hardness of no less than 90% of that of the original wood. These physical performance indicators directly affect the service life and actual application effect of the flooring and must be strictly controlled.

[0117] Environmental performance testing, including formaldehyde emission, heavy metal content, and VOC (volatile organic compound) testing, is a crucial step in ensuring product environmental friendliness. Formaldehyde emission testing uses the climate chamber method, conducted according to GB 18580 standard, requiring formaldehyde emission to not exceed 0.05 mg / m³, meeting the E0 standard. Heavy metal content testing primarily targets harmful heavy metals such as lead, mercury, cadmium, and chromium, conducted according to GB / T 22048 standard, requiring all indicators to meet national limits. VOC testing uses the small environmental chamber method, conducted according to GB / T 29899 standard, requiring TVOC emission to not exceed 0.4 mg / m³. These environmental indicators are important guarantees of product safety, directly related to consumer health and indoor environmental quality.

[0118] The final step before products leave the factory is to grade and package environmentally compliant flooring products according to different specifications and color differences, and attach product quality inspection reports and environmental certification labels. The grading and packaging are based on the flooring's dimensions, color difference, and surface quality, typically divided into three grades: Premium, Grade 1, and Grade 2. Premium grade products have minimal color difference and no surface defects; Grade 1 products have slight color difference and inconspicuous surface defects; Grade 2 products have noticeable color difference but within acceptable limits, and a few surface defects that do not affect usability. Each package includes a quality inspection report detailing the physical and environmental performance test results, and is affixed with environmental certification labels such as the China Environmental Label and FSC certification, enhancing consumer trust and acceptance of the product.

[0119] This application also provides an environmentally friendly solid wood flooring that uses a deep carbonization process and is manufactured using the method described above.

[0120] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the inventive concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

[0121] Finally, it should be noted that the above-described embodiments are merely specific implementations of this disclosure, used to illustrate the technical solutions of this disclosure, and not to limit it. The protection scope of this disclosure is not limited thereto. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this disclosure; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure, and should all be covered within the protection scope of this disclosure. Therefore, the protection scope of this disclosure should be determined by the protection scope of the claims.

Claims

1. A method for producing environmentally friendly solid wood flooring using a deep carbonization process, characterized in that, Includes the following steps: The raw wood material is obtained, and the moisture content of the wood is controlled within the range of 8%-12% through natural drying or low-temperature drying. Surface impurities are removed using cleaning equipment, and the wood is cut to standard specifications and inspected for quality to obtain pre-treated qualified wood. The pre-treated wood is placed in a special reactor according to the specified loading method. The temperature of the reactor is raised to 190℃-212℃ at a heating rate of 15℃-20℃ per hour and maintained at a constant temperature for 2-4 hours. Through the action of high temperature, the hemicellulose and some cell wall components in the wood undergo a pyrolysis reaction to obtain wood that has undergone deep carbonization treatment. Turn off the heating system and reduce the temperature of the reactor to below 60°C at a cooling rate of 10°C-15°C per hour. Turn on the ventilation system to accelerate cooling and remove the reaction gas. Take out the wood after deep carbonization treatment and place it in a constant temperature and humidity environment for 48-72 hours of stabilization curing to obtain carbonized wood after stabilization treatment. The carbonized wood after stabilization treatment is finely sanded using sanding equipment, and a water-based waterproof coating is prepared and evenly applied to the wood surface using a multi-layer thin-coat process to obtain the waterproof carbonized wood. The carbonized wood that has undergone waterproofing treatment is precisely cut into standard-sized floor strips according to flooring product standards, and then tongue and groove processing and final quality inspection are carried out to obtain environmentally friendly solid wood flooring products.

2. The method according to claim 1, characterized in that, The log material is pretreated to obtain pretreated and qualified timber, including: Based on the aforementioned log material, the moisture content is precisely controlled using natural drying or low-temperature drying processes, so that the wood moisture content reaches the range of 8%-12%. For wood with a moisture content in the range of 8%-12%, use specialized cleaning equipment to remove surface dust, grease and other impurities to obtain clean wood. The cleaned wood is cut into standard sizes suitable for reactor processing, and quality inspection is performed to remove obvious defects, thus obtaining the pre-treated qualified wood.

3. The method according to claim 1, characterized in that, The carbonization temperature of 190℃-212℃ is set differently according to the type of wood, with hardwoods using a temperature range of 195℃-212℃ and softwoods using a temperature range of 190℃-205℃.

4. The method according to claim 1, characterized in that, During the deep carbonization process, based on the pretreated and qualified wood, an appropriate amount of steam is injected to maintain the humidity environment inside the reactor to prevent the wood from cracking due to excessive dehydration. At the same time, the temperature, pressure and humidity parameters during the reaction process are monitored to obtain the wood after deep carbonization.

5. The method according to claim 1, characterized in that, The deeply carbonized wood is removed and placed in a constant temperature and humidity environment for 48-72 hours for stabilization, resulting in stabilized carbonized wood, including: Based on the wood after deep carbonization treatment, the heating system is turned off and the temperature of the reactor is gradually reduced at a cooling rate of 10℃-15℃ per hour, so that the temperature drops steadily to below 60℃. When the temperature of the reactor drops below 60°C, the ventilation system is turned on to accelerate the cooling process and remove the gas produced by the reaction, thus obtaining carbonized wood after cooling and exhaust treatment. The carbonized wood after cooling and venting treatment is taken out of the reactor and placed in a constant temperature and humidity environment for 48-72 hours for stabilization curing to obtain the stabilized carbonized wood.

6. The method according to claim 1, characterized in that, Based on the carbonized wood after the stabilization treatment, the carbonized layer is removed by fine sanding using sanding equipment. A water-based waterproof coating without formaldehyde and other harmful substances is prepared and evenly applied to the wood surface using a multi-layer thin-coat process and allowed to dry fully to obtain the carbonized wood after the waterproof treatment.

7. The method according to claim 3, characterized in that, A carbonization temperature correction formula was established based on wood density and cellulose content. Carbonization temperatures were set separately for hardwoods and softwoods, and the carbonization time was adjusted according to the initial moisture content of the wood. For wood with higher moisture content, the treatment time was extended by 30-60 minutes.

8. The method according to claim 1, characterized in that, The deep carbonization process employs a staged temperature control process, including: After loading the pretreated wood into a special reactor, the temperature of the reactor is raised to the first stage temperature of 160℃-180℃ at a heating rate of 15℃-20℃ per hour, and maintained for 1-2 hours for pre-carbonization treatment to obtain pre-carbonized wood. The pre-carbonized wood is further heated to the second stage temperature of 190℃-212℃ and maintained for 2-4 hours for deep carbonization treatment, so that the hemicellulose and some cell wall components in the wood undergo a full pyrolysis reaction to obtain the wood after deep carbonization treatment.

9. The method according to claim 1, characterized in that, The method further includes adding a surface modification treatment during the stabilization curing process, including: Based on the carbonized wood after the stabilization treatment, a special equipment is used to treat the surface carbonization layer. The loose carbonization layer is removed by light sanding to obtain the surface-treated carbonized wood. The carbonized wood after surface treatment is subjected to natural plant oil penetration treatment, which allows the plant oil to penetrate deep into the wood fibers to enhance stability, resulting in carbonized wood after penetration modification. The carbonized wood that has undergone permeation modification is allowed to dry naturally for 24-48 hours to allow the plant oil to fully solidify and combine with the wood fibers, resulting in modified and stable carbonized wood, which is then used as the input material for the waterproofing treatment step.

10. An environmentally friendly solid wood flooring process employing deep carbonization treatment, characterized in that, It is prepared by the method described in any one of claims 1-9.

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