Thin wood veneer decorative board chemical surface treatment
2024-04-21 09:08:41
With the improvement of people's living standards and the urgent need to improve the living environment and conditions, the amount of decorative panels is increasing. So far, there are nearly 100 wooden decorative board manufacturers in our province. The daily output of this kind of decorative board has reached 300,000 to 400,000, and the annual output value is nearly 10 billion. In just a few years, it has developed into our province. A large plywood secondary processing industry. The wooden decorative panels are generally made of high-quality wood, such as white birch, maple, eucalyptus, sapele, flower palm, rosewood, ash, and various kinds of artificial wood. Planing, storage, transportation, parquet, adhesive tape, hot pressing and many other processes. But these complicated processes make the original wooden texture curve lose its natural and fresh feeling. Only ash has no domestic resources, and it has to be imported from Russia. Due to the geographical, environmental, climatic, and annual rings of wood growth, the material color difference is large, the color is not clear, and even black, etc. effect. At present, many manufacturers have caused a backlog of products due to these reasons, and prices are not going up. Some manufacturers are even at risk of bankruptcy. For this reason, the surface treatment of wooden decorative panels has important practical significance.
1 Source and treatment of thin wood color
The discoloration of wood is very complicated, and the wood of different types of wood has different discoloration. From a chemical point of view, wood discoloration is considered to be mainly chemical discoloration groups, CC bonds, CO bonds, vinyl (CH2 CHR), etc., and groups that assist in the discoloration of wood such as OH-based, methoxy (CHO), carboxyl (COOH), etc., the chemical components of discoloration mainly include phenols, anthraquinones, organic acids, iridoids, tannins, and various wood extracts [1, 2]. Therefore, for the surface treatment of different types of decorative panels, or commonly known as bleaching, first of all, preliminary chemical analysis of the color-changing components of the wood must be carried out to determine the range of color-changing components and the nature of discoloration, and to analyze the components of discoloration. A more reasonable surface treatment (bleaching) process is developed for the biological and physical factors that cause discoloration. At the same time, as people's living standards improve, people's pursuit of beauty and consumption levels are different, and the processing techniques and results are also processed. Some changes should be made accordingly. From the analysis of the color-changing components, the colored chemical components and the chemical components that cause discoloration are the main factors causing discoloration of the wood. However, these biological and physical factors should also pay attention to each other. For example, the wood itself is cut into thin wood and exposed to the air, causing the chemical substance to oxidize and discolor. In terms of temperature and humidity, the temperature rises, the activation energy of the chemical reaction decreases, the oxidation of the color-changing substance accelerates, and the humidity also causes the discoloration substances such as phenolic substances and organic acids to accelerate to dissipate into contact with the air; the change of temperature and humidity also causes mildew in the wood; Tree species growth geography, environment, annual rings, fiber growth and so on will cause different distribution of colored and discolored substances, which will bring more difficulties to the surface treatment work. For this reason, chemical treatment of these discolored components can be carried out by oxidation and reduction, in order to use the treatment liquid to destroy the divalent bond between the carbonyl (CO) and other carbon atoms in the chromonic component of the wood. The absorbable light moves in the short-wave direction and weakens its absorption intensity [3, 4], so that the color of the material becomes lighter, the texture becomes clear and elegant, more natural and vivid, and the whole process of processing is actually a The physicochemical process of surface treatment. The surface treatment method of veneer veneer can be divided into two methods: immersion method and roll coating method. From the investigation and treatment effect of the current enterprises in Zhejiang Province, and the acceptable procedures for the surface treatment technology, the company prefers the roll coating method. deal with. Therefore, the theoretical study of the surface treatment of the roll coating method is also very necessary.
2 Influence of wood structure and treatment liquid on surface treatment effect
2 1 Wood structure and treatment effect In the various veneer decorative panels which can be surface treated, the effect of the wood structure itself on the treatment effect is always present. There are various kinds of grooves, ducts, tracheids, wood rays, etc. in the wood structure. On the one hand, the existence of these structures causes surface irregularities, and at the same time accelerates the penetration of the treatment liquid into the internal structure to achieve a certain bleaching. On the other hand, due to the uneven distribution of the treatment liquid caused by these structures and different ages, annual rings, core materials and sapwood, the treatment effect is affected. Regardless of how the surface itself is treated, the effect of the structure itself on the penetration and diffusion of the treatment fluid is important.
2 2 Surface treatment kinetics
The diffusion of the treatment liquid inside the wood structure, there are actually some physical and chemical processes, first of all, the "enveloping effect" [6], because the average distance between liquid molecules is much closer than the gas, each treatment liquid molecule in the liquid is actually surrounded by the surrounding molecules. Surrounded by the liquid molecules that enter the interior of the wood tissue are also surrounded by other molecules, just like in the cage made up of surrounding molecules, the molecules in this cage can not be freely translated like gas molecules, can only keep on The vibration in the cage, constantly colliding with surrounding molecules. If a vibration accumulates enough energy, or is vibrating in a certain direction, the surrounding molecules in that direction just open the way, so the molecule will break through the cage and spread elsewhere. . Go on without interruption.
Therefore, for the surface treatment of the decorative board, each solute molecule in the treatment liquid is in the cage formed by the surrounding solvent molecules. If the two solute molecules diffuse into the same cage and contact each other, it is called encounter [5] ]. The two solute molecules can only undergo a bleaching reaction if they are diffused into the same cage. The diffusion and bleaching reactions are two series steps. If the reaction activation energy can not keep up with the reaction rate, it is diffusion control; conversely, if the reaction activation energy is large and the reaction rate is slow, it is reaction control or activation control [6]. From the combination of practical and theoretical experience of Zhejiang Deqing Shuangma Wood Industry Co., Ltd. for more than half a year, if the bleaching enters the diffusion control, it will easily cause the wood grain texture to be blurred, the bleaching is uneven, and the sharpness is not enough. If the bleaching enters the reaction control, it will easily cause uneven distribution of the decorative surface of the bleaching liquid, so that the whole board is unevenly bleached, and the sheet will produce "water shadow". Therefore, how to choose diffusion control and reaction control steps during the bleaching process of the board is very important. For the diffusion reaction, the first law of Fick diffusion must be observed: the mole number dni/dt of the treatment liquid substance i per unit time of the cross-sectional area S per unit time at a certain temperature, proportional to the cross-sectional area S and the concentration gradient dci/ The product of dxi, ie: dnidt=-DS·dcidx where D is the diffusion coefficient in m2 ·s-1, for general spherical particles: D = RT6Lπηγ where: L is the Avogadro constant, η is the viscosity and γ is the radius of the spherical particles. Therefore, the diffusion of the wood material treatment liquid is related to the density of the material structure, the viscosity of the treatment liquid itself, the molecular size, and the like. For the activation control reaction, the reaction is in accordance with the Arrhenius equation, K = K0 e-Ea / RT. Where: K is the reaction rate constant, Ea is the reaction activation energy, and T is the temperature. Therefore, the activation control determines the reaction energy and the temperature of the treatment liquid.
3 Photochemical and wood environmental studies of wood surface treatment
Wood is the main material that constitutes the indoor living environment of human beings, and the decorative panels undoubtedly play an important role. The effect of light on the surface of these materials is also a non-negligible aspect. For example, when wood is exposed to light, it will cause photodegradation and photooxidation degradation. Ultraviolet rays will illuminate the wood, causing lignin components to interact and become discolored and deteriorated. How to prevent, reduce or eliminate the influence of light on the color and material of wood is very meaningful.
The laws of photochemistry indicate that in order for a photochemical reaction to occur, certain components of the system must first absorb light, and wood is a substance that absorbs light. The second law of photochemistry tells people that a molecule can only absorb the quantum of one radiation. Absorbing energy dissociates bonds in the molecules of each component of the wood. This homogenization generates free radicals and serves as an initial product of photochemistry while forming chromophoric groups such as carboxyl groups, carbonyl groups, hydrazines, and conjugated double bonds. Light is an electromagnetic radiation that belongs to a certain wavelength range. When the light illuminates the surface of the wood, part of it is reflected, and part of it enters wood pigment (colored matter) and cell gap which can absorb certain wavelengths. Light that is not absorbed into the cells is re-emitted by scattering, reflection, and conduction, thereby producing a wood color through the human retina. However, the maximum distance of light into the wood does not exceed 200 μm [2, 4], so photochemical reactions occur, just a surface process. For this reason, from the photochemical reaction phenomenon of wood, the surface treatment of decorative panels is particularly important. Through the chemical treatment of this surface, it is possible to decompose or eliminate substances that easily absorb colored light and substances that are colored or easily discolored, in order to achieve uniformity of color. Wood is a natural product of biological origin, its nature has its high diversity and variability. It is these diversity and variability that make wood form its unique and colorful world regardless of color, structure and materiality. It brings peace, warmth and natural beauty to people, and this natural biological material is getting more and more people's attention. Japanese scholars [7] proposed that wood environment science is a complementary relationship between wood and people's thinking, emotion, and living space. Some scholars have studied [8, 9], the fluctuation of irregular small fluctuations in a horizontal line of a certain system in nature, such as this fluctuation to the 1 / f type fluctuation spectrum. It is consistent with the human rhythm of human beings, which can give people a sense of excitement, and the wood itself has textures and tones consistent with the rhythm of such people [7, 8]. However, due to various factors such as light, heat, humidity, processing, transportation, environment, climate and biological mildew, wood has a phenomenon that is inconsistent with the texture and color of wood, or distortion and loss of beauty. Surface treatment. Therefore, the surface treatment of wooden decorative panels is a multidisciplinary process, which should be based on modern chemical reaction theory, optics, wood environment, etc., in order to achieve the best treatment effect.
4 process parameters and processing effects
In the analysis of the surface treatment kinetics of the treatment liquid, the reaction speed, temperature, treatment pre-release time and treatment liquid concentration of the bleaching treatment are process parameters in the entire surface treatment.
4 1 Reaction speed
The reaction rate is too fast, the reaction is diffusion control, the heat of the treatment liquid is large, and the heat is accumulated too much, which causes the treatment liquid to bump, and finally the entire treatment liquid fails. At the same time, the reaction speed is too fast, which also has certain influence on the quality of the panel, such as damage and blurring of the fiber stripe, damage of the bonding strength, etc.; the osmotic reaction of the treatment liquid on the veneer is not uniform, the effect is inconsistent, and the "yin and yang" or "flower face" is produced. Phenomenon, which affects the quality of the entire board.
The reaction rate is too slow, and the kinetics are controlled by the reaction. On the one hand, it affects the production efficiency; on the other hand, due to the roll coating method, the amount of the treatment liquid applied to the panel is uneven, or the plate is not completely flat, resulting in uneven distribution of the treatment liquid, thereby causing " The unevenness of the bleaching treatment effect also causes a more serious "face", which is much more serious than the diffusion control. To this end, the best way to solve this contradiction theoretically is to appropriately increase the panel temperature, in order to speed up the reaction speed, eliminate the "flower face" and improve the quality under the premise of reaction control.
In summary, the reaction rate should be properly controlled.
4 2 temperature
The temperature can be divided into three stages: the storage temperature of the treatment liquid, the reaction temperature (ie, the storage temperature of the panel after the panel is painted), and the hot pressing temperature of the panel during the entire surface treatment process.
4 2 1 treatment liquid storage temperature
For formulated oxidized or reduced treatment fluids, the temperature primarily affects the effective use of the formulation. According to the principle of chemical reaction speed, the temperature is increased and the reaction speed is increased. Sometimes, in some manufacturers, the preparation liquid has not been completely used, which has caused the effective action of the treatment liquid to be invalid or reduced, resulting in a "gradient" of processing (bleaching) between decorative panels. Phenomenon, which affects quality. Therefore, the temperature of the treatment liquid should be properly controlled.
4 2 2 reaction temperature
In the process of industrial production of decorative panels, before the panel is treated with the color surface, the decorative panels are stacked by thin-layer hot-pressing, and the panel temperature is the actual reaction temperature, which is about 20 to 60 °C, and 40. ~ 60 ° C is very good, because of the oxidation type (such as H2 O2, Na ClO, peracetic acid, etc.) or reduced (such as NaHSO3, H2 C2 O4, sodium dithionite, etc.) chemicals, this temperature zone is suitable for decorative panel chemistry The treatment is initiated, and at the same time, the temperature is too high, and the reaction is accelerated to damage the wood fiber [1, 3]. However, the reaction rate to the surface treatment, the reaction temperature is in accordance with the Arrhenius velocity equation, so that it is completely controllable in actual production.
4 2 3 panel hot pressing temperature
The panel is baked by using the existing press equipment on the production, through the baking, the purpose is to completely eliminate excess chemicals, dry the panel and stabilize the quality. At the same time, it should be noted that the baking temperature should not be too high. Because on the one hand, the wood fiber is damaged and blurred, on the other hand, bubble degumming occurs. By summarizing, in order to meet the needs of modern production, the general drying temperature is preferably 80 to 100 °C.
4 3 treatment liquid concentration
The concentration of the treatment liquid is directly related to the reaction speed of the treatment, the whiteness of the panel, etc., which has been discussed from the foregoing reaction kinetics. Practice has proved that it is crucial to properly select the concentration of the treatment fluid to ensure the quality of the panel and meet the requirements of the customer, and to produce decorative panels of different whiteness.
5 Conclusion
In order to improve the decorative performance of the decorative panel, for such veneer veneer decorative panels, chemical surface treatment is generally required, and the surface of the decorative panel can be made more natural and beautiful by the treatment, thereby improving the overall quality grade of the decorative panel. Zhejiang Province is a large wood processing province, and timber resources are basically imported and transported by other provinces. To this end, the effective use of timber resources is more urgent, and it has special significance for the theoretical and practical research of chemical surface treatment of decorative panels.
1 Source and treatment of thin wood color
The discoloration of wood is very complicated, and the wood of different types of wood has different discoloration. From a chemical point of view, wood discoloration is considered to be mainly chemical discoloration groups, CC bonds, CO bonds, vinyl (CH2 CHR), etc., and groups that assist in the discoloration of wood such as OH-based, methoxy (CHO), carboxyl (COOH), etc., the chemical components of discoloration mainly include phenols, anthraquinones, organic acids, iridoids, tannins, and various wood extracts [1, 2]. Therefore, for the surface treatment of different types of decorative panels, or commonly known as bleaching, first of all, preliminary chemical analysis of the color-changing components of the wood must be carried out to determine the range of color-changing components and the nature of discoloration, and to analyze the components of discoloration. A more reasonable surface treatment (bleaching) process is developed for the biological and physical factors that cause discoloration. At the same time, as people's living standards improve, people's pursuit of beauty and consumption levels are different, and the processing techniques and results are also processed. Some changes should be made accordingly. From the analysis of the color-changing components, the colored chemical components and the chemical components that cause discoloration are the main factors causing discoloration of the wood. However, these biological and physical factors should also pay attention to each other. For example, the wood itself is cut into thin wood and exposed to the air, causing the chemical substance to oxidize and discolor. In terms of temperature and humidity, the temperature rises, the activation energy of the chemical reaction decreases, the oxidation of the color-changing substance accelerates, and the humidity also causes the discoloration substances such as phenolic substances and organic acids to accelerate to dissipate into contact with the air; the change of temperature and humidity also causes mildew in the wood; Tree species growth geography, environment, annual rings, fiber growth and so on will cause different distribution of colored and discolored substances, which will bring more difficulties to the surface treatment work. For this reason, chemical treatment of these discolored components can be carried out by oxidation and reduction, in order to use the treatment liquid to destroy the divalent bond between the carbonyl (CO) and other carbon atoms in the chromonic component of the wood. The absorbable light moves in the short-wave direction and weakens its absorption intensity [3, 4], so that the color of the material becomes lighter, the texture becomes clear and elegant, more natural and vivid, and the whole process of processing is actually a The physicochemical process of surface treatment. The surface treatment method of veneer veneer can be divided into two methods: immersion method and roll coating method. From the investigation and treatment effect of the current enterprises in Zhejiang Province, and the acceptable procedures for the surface treatment technology, the company prefers the roll coating method. deal with. Therefore, the theoretical study of the surface treatment of the roll coating method is also very necessary.
2 Influence of wood structure and treatment liquid on surface treatment effect
2 1 Wood structure and treatment effect In the various veneer decorative panels which can be surface treated, the effect of the wood structure itself on the treatment effect is always present. There are various kinds of grooves, ducts, tracheids, wood rays, etc. in the wood structure. On the one hand, the existence of these structures causes surface irregularities, and at the same time accelerates the penetration of the treatment liquid into the internal structure to achieve a certain bleaching. On the other hand, due to the uneven distribution of the treatment liquid caused by these structures and different ages, annual rings, core materials and sapwood, the treatment effect is affected. Regardless of how the surface itself is treated, the effect of the structure itself on the penetration and diffusion of the treatment fluid is important.
2 2 Surface treatment kinetics
The diffusion of the treatment liquid inside the wood structure, there are actually some physical and chemical processes, first of all, the "enveloping effect" [6], because the average distance between liquid molecules is much closer than the gas, each treatment liquid molecule in the liquid is actually surrounded by the surrounding molecules. Surrounded by the liquid molecules that enter the interior of the wood tissue are also surrounded by other molecules, just like in the cage made up of surrounding molecules, the molecules in this cage can not be freely translated like gas molecules, can only keep on The vibration in the cage, constantly colliding with surrounding molecules. If a vibration accumulates enough energy, or is vibrating in a certain direction, the surrounding molecules in that direction just open the way, so the molecule will break through the cage and spread elsewhere. . Go on without interruption.
Therefore, for the surface treatment of the decorative board, each solute molecule in the treatment liquid is in the cage formed by the surrounding solvent molecules. If the two solute molecules diffuse into the same cage and contact each other, it is called encounter [5] ]. The two solute molecules can only undergo a bleaching reaction if they are diffused into the same cage. The diffusion and bleaching reactions are two series steps. If the reaction activation energy can not keep up with the reaction rate, it is diffusion control; conversely, if the reaction activation energy is large and the reaction rate is slow, it is reaction control or activation control [6]. From the combination of practical and theoretical experience of Zhejiang Deqing Shuangma Wood Industry Co., Ltd. for more than half a year, if the bleaching enters the diffusion control, it will easily cause the wood grain texture to be blurred, the bleaching is uneven, and the sharpness is not enough. If the bleaching enters the reaction control, it will easily cause uneven distribution of the decorative surface of the bleaching liquid, so that the whole board is unevenly bleached, and the sheet will produce "water shadow". Therefore, how to choose diffusion control and reaction control steps during the bleaching process of the board is very important. For the diffusion reaction, the first law of Fick diffusion must be observed: the mole number dni/dt of the treatment liquid substance i per unit time of the cross-sectional area S per unit time at a certain temperature, proportional to the cross-sectional area S and the concentration gradient dci/ The product of dxi, ie: dnidt=-DS·dcidx where D is the diffusion coefficient in m2 ·s-1, for general spherical particles: D = RT6Lπηγ where: L is the Avogadro constant, η is the viscosity and γ is the radius of the spherical particles. Therefore, the diffusion of the wood material treatment liquid is related to the density of the material structure, the viscosity of the treatment liquid itself, the molecular size, and the like. For the activation control reaction, the reaction is in accordance with the Arrhenius equation, K = K0 e-Ea / RT. Where: K is the reaction rate constant, Ea is the reaction activation energy, and T is the temperature. Therefore, the activation control determines the reaction energy and the temperature of the treatment liquid.
3 Photochemical and wood environmental studies of wood surface treatment
Wood is the main material that constitutes the indoor living environment of human beings, and the decorative panels undoubtedly play an important role. The effect of light on the surface of these materials is also a non-negligible aspect. For example, when wood is exposed to light, it will cause photodegradation and photooxidation degradation. Ultraviolet rays will illuminate the wood, causing lignin components to interact and become discolored and deteriorated. How to prevent, reduce or eliminate the influence of light on the color and material of wood is very meaningful.
The laws of photochemistry indicate that in order for a photochemical reaction to occur, certain components of the system must first absorb light, and wood is a substance that absorbs light. The second law of photochemistry tells people that a molecule can only absorb the quantum of one radiation. Absorbing energy dissociates bonds in the molecules of each component of the wood. This homogenization generates free radicals and serves as an initial product of photochemistry while forming chromophoric groups such as carboxyl groups, carbonyl groups, hydrazines, and conjugated double bonds. Light is an electromagnetic radiation that belongs to a certain wavelength range. When the light illuminates the surface of the wood, part of it is reflected, and part of it enters wood pigment (colored matter) and cell gap which can absorb certain wavelengths. Light that is not absorbed into the cells is re-emitted by scattering, reflection, and conduction, thereby producing a wood color through the human retina. However, the maximum distance of light into the wood does not exceed 200 μm [2, 4], so photochemical reactions occur, just a surface process. For this reason, from the photochemical reaction phenomenon of wood, the surface treatment of decorative panels is particularly important. Through the chemical treatment of this surface, it is possible to decompose or eliminate substances that easily absorb colored light and substances that are colored or easily discolored, in order to achieve uniformity of color. Wood is a natural product of biological origin, its nature has its high diversity and variability. It is these diversity and variability that make wood form its unique and colorful world regardless of color, structure and materiality. It brings peace, warmth and natural beauty to people, and this natural biological material is getting more and more people's attention. Japanese scholars [7] proposed that wood environment science is a complementary relationship between wood and people's thinking, emotion, and living space. Some scholars have studied [8, 9], the fluctuation of irregular small fluctuations in a horizontal line of a certain system in nature, such as this fluctuation to the 1 / f type fluctuation spectrum. It is consistent with the human rhythm of human beings, which can give people a sense of excitement, and the wood itself has textures and tones consistent with the rhythm of such people [7, 8]. However, due to various factors such as light, heat, humidity, processing, transportation, environment, climate and biological mildew, wood has a phenomenon that is inconsistent with the texture and color of wood, or distortion and loss of beauty. Surface treatment. Therefore, the surface treatment of wooden decorative panels is a multidisciplinary process, which should be based on modern chemical reaction theory, optics, wood environment, etc., in order to achieve the best treatment effect.
4 process parameters and processing effects
In the analysis of the surface treatment kinetics of the treatment liquid, the reaction speed, temperature, treatment pre-release time and treatment liquid concentration of the bleaching treatment are process parameters in the entire surface treatment.
4 1 Reaction speed
The reaction rate is too fast, the reaction is diffusion control, the heat of the treatment liquid is large, and the heat is accumulated too much, which causes the treatment liquid to bump, and finally the entire treatment liquid fails. At the same time, the reaction speed is too fast, which also has certain influence on the quality of the panel, such as damage and blurring of the fiber stripe, damage of the bonding strength, etc.; the osmotic reaction of the treatment liquid on the veneer is not uniform, the effect is inconsistent, and the "yin and yang" or "flower face" is produced. Phenomenon, which affects the quality of the entire board.
The reaction rate is too slow, and the kinetics are controlled by the reaction. On the one hand, it affects the production efficiency; on the other hand, due to the roll coating method, the amount of the treatment liquid applied to the panel is uneven, or the plate is not completely flat, resulting in uneven distribution of the treatment liquid, thereby causing " The unevenness of the bleaching treatment effect also causes a more serious "face", which is much more serious than the diffusion control. To this end, the best way to solve this contradiction theoretically is to appropriately increase the panel temperature, in order to speed up the reaction speed, eliminate the "flower face" and improve the quality under the premise of reaction control.
In summary, the reaction rate should be properly controlled.
4 2 temperature
The temperature can be divided into three stages: the storage temperature of the treatment liquid, the reaction temperature (ie, the storage temperature of the panel after the panel is painted), and the hot pressing temperature of the panel during the entire surface treatment process.
4 2 1 treatment liquid storage temperature
For formulated oxidized or reduced treatment fluids, the temperature primarily affects the effective use of the formulation. According to the principle of chemical reaction speed, the temperature is increased and the reaction speed is increased. Sometimes, in some manufacturers, the preparation liquid has not been completely used, which has caused the effective action of the treatment liquid to be invalid or reduced, resulting in a "gradient" of processing (bleaching) between decorative panels. Phenomenon, which affects quality. Therefore, the temperature of the treatment liquid should be properly controlled.
4 2 2 reaction temperature
In the process of industrial production of decorative panels, before the panel is treated with the color surface, the decorative panels are stacked by thin-layer hot-pressing, and the panel temperature is the actual reaction temperature, which is about 20 to 60 °C, and 40. ~ 60 ° C is very good, because of the oxidation type (such as H2 O2, Na ClO, peracetic acid, etc.) or reduced (such as NaHSO3, H2 C2 O4, sodium dithionite, etc.) chemicals, this temperature zone is suitable for decorative panel chemistry The treatment is initiated, and at the same time, the temperature is too high, and the reaction is accelerated to damage the wood fiber [1, 3]. However, the reaction rate to the surface treatment, the reaction temperature is in accordance with the Arrhenius velocity equation, so that it is completely controllable in actual production.
4 2 3 panel hot pressing temperature
The panel is baked by using the existing press equipment on the production, through the baking, the purpose is to completely eliminate excess chemicals, dry the panel and stabilize the quality. At the same time, it should be noted that the baking temperature should not be too high. Because on the one hand, the wood fiber is damaged and blurred, on the other hand, bubble degumming occurs. By summarizing, in order to meet the needs of modern production, the general drying temperature is preferably 80 to 100 °C.
4 3 treatment liquid concentration
The concentration of the treatment liquid is directly related to the reaction speed of the treatment, the whiteness of the panel, etc., which has been discussed from the foregoing reaction kinetics. Practice has proved that it is crucial to properly select the concentration of the treatment fluid to ensure the quality of the panel and meet the requirements of the customer, and to produce decorative panels of different whiteness.
5 Conclusion
In order to improve the decorative performance of the decorative panel, for such veneer veneer decorative panels, chemical surface treatment is generally required, and the surface of the decorative panel can be made more natural and beautiful by the treatment, thereby improving the overall quality grade of the decorative panel. Zhejiang Province is a large wood processing province, and timber resources are basically imported and transported by other provinces. To this end, the effective use of timber resources is more urgent, and it has special significance for the theoretical and practical research of chemical surface treatment of decorative panels.
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