A method for dyeing bamboo wood by using biological pigments

Abstract

The present application relates to bamboo wood dyeing technical field, specifically disclose a kind of method for dyeing bamboo wood using biological pigment, comprising the following steps:1) biological pigment preparation;2) bamboo wood pretreatment;3) bamboo wood modification treatment;4) dyeing treatment;5) drying treatment.The product prepared by the present application has good dyeing uniformity, good color fixing effect, good permeability, safety and environmental protection, and is especially suitable for kitchen, children's toys and other fields.

Description

Technical Field

[0001] This invention relates to the field of bamboo and wood dyeing technology, specifically to a method for dyeing bamboo and wood using biological pigments. Background Technology

[0002] Bamboo and wood dyeing can enhance their color and decorative effect. To ensure the environmental friendliness and safety of the products, existing technologies use pure natural pigments or pigments produced by microbial fermentation to dye bamboo and wood. For example, Chinese patent CN 103203787 B discloses a method for dyeing bamboo and wood tableware using sucrose as a dye. Sucrose is dissolved in water to prepare a 3-10% sucrose solution by weight. The bamboo tableware is then immersed in the sucrose solution to fully absorb the sugar solution, drained, and then dried in a drying oven at 130-190℃ to achieve a brick-red color. Chinese patent 111015862A discloses a method for dyeing bamboo and wood with biological pigments. The process steps include: 1) culturing discoloration fungi into a dyeing fungal solution; 2) inoculating bamboo and wood by immersing them in the dyeing fungal solution; 3) controlling the growth rate and pigment secretion of the discoloration fungi on different surfaces of the bamboo and wood; 4) sterilizing the dyed bamboo and wood; and 5) maintaining a balanced state. This method utilizes the excellent biocompatibility and antioxidant properties of discoloration fungi in bamboo and wood to achieve dyeing. However, the above technologies all have problems: the dyeing is not thorough or uniform enough, and the dyeing agent cannot penetrate the bamboo and wood deeply and evenly. This makes it difficult to guarantee the aesthetics of the products made after further processing of bamboo chips, and the color fixation effect is generally poor, with the products fading during storage or use. These issues urgently need to be improved. Summary of the Invention

[0003] The technical problem solved by this invention is to provide a method for dyeing bamboo and wood using biological pigments, so as to further improve the dyeing depth and color fixation effect of bamboo and wood, and improve the dyeing uniformity.

[0004] The technical problem solved by this invention is achieved by the following technical solution:

[0005] A method for staining bamboo and wood using biological pigments includes the following steps:

[0006] 1) Preparation of bio-pigment: After the color-changing bacteria are activated, they are inoculated into a fermenter for further fermentation. After fermentation, the pigment liquid is extracted for later use. The color-changing bacteria is *Gibberel labaccata*.

[0007] 2) Bamboo and wood pretreatment: After removing the green bamboo and the waxy layer inside the bamboo, the raw bamboo is processed into bamboo strips; the bamboo and wood are steamed and then bleached with bleaching agent. After bleaching, they are taken out and drained.

[0008] 3) Bamboo and wood modification treatment: The bamboo strips treated in step 1) are modified with an alkaline solution with a mass fraction of 0.4-1.0%. Ultrasonic assistance is used in the treatment process. The treatment temperature is 65-75℃ and the treatment time is 20-40 minutes. After the treatment is completed, the bamboo strips are frozen. After the freezing treatment is completed, the bamboo strips are thawed and cleaned for use.

[0009] 4) Dyeing treatment: Immerse the bamboo strips treated in step 3) into the dyeing solution. During the dyeing process, maintain the temperature at 30-50℃, the pressure inside the tank at 0.2-0.6MPa, and the dyeing time at 3-5h.

[0010] 5) Drying treatment: Take out the bamboo strips that have been treated in step 4), wash off the surface dye, and then dry them.

[0011] Further, in step 1), the liquid culture medium in the fermenter includes the following raw materials in parts by weight: 200 g / L of potatoes, 20 g / L of glucose, 2.5 g / L of yeast extract, and 0.005 g / L of KH2PO4, and the pH of the liquid culture medium is adjusted to 7.0.

[0012] Further, in step 1), the inoculation amount of the fermenter is 4-6%, the fermentation temperature is 20-30℃, and the fermentation time is 70-80h.

[0013] Furthermore, in step 2), the thickness of the bamboo strips is 6–10 mm.

[0014] Further, in step 2), the bleaching agent is a hydrogen peroxide solution with a mass fraction of 10-15%, and the bleaching time is 0.5-1h.

[0015] Furthermore, in step 3), the power of the ultrasonic wave is 1000-1200W.

[0016] Further, in step 3), the freezing treatment involves freezing the bamboo strips at -20 to -40°C for 20 to 40 hours.

[0017] Furthermore, in step 4), the staining process is carried out by heating and pressurizing.

[0018] Furthermore, in step 4), the pH of the staining solution is adjusted to 2-6 and the pH of the staining solution is kept stable during the staining process.

[0019] Further, in step 5), the cleaned bamboo strips are dried at a constant temperature of 100-130℃ until the moisture content is 8-10%.

[0020] Beneficial effects: The method for dyeing bamboo and wood using biological pigments described in this invention produces products with excellent dyeing uniformity, good color fixation, good permeability, and is safe and environmentally friendly. It can be well applied in the fields of kitchenware, children's toys, etc. Detailed Implementation

[0021] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific embodiments.

[0022] The present invention discloses a method for dyeing bamboo and wood using biological pigments, comprising the following steps:

[0023] 1) Preparation of bio-pigment: After activation, the color-changing bacteria are inoculated into a fermenter for further fermentation. After fermentation, the pigment solution is extracted for later use. Specifically, the color-changing bacteria is *Gibberellic acid bacterium* (Gibberel labaccata), which is commercially purchased. During activation, the color-changing bacteria are inoculated into a seed culture medium consisting of 200 g / L potato, 20 g / L glucose, pH 7.0, and cultured at 25°C and 180 rpm for 40 h on a shaker. Then, 4–6% of the seed culture is inoculated into the fermenter for further fermentation. The liquid culture medium in the fermenter consists of the following components by weight: 200 g / L potato, 20 g / L glucose, 2.5 g / L yeast extract, and 0.005 g / L KH₂PO₄, with the pH adjusted to 7.0. The fermentation temperature in the fermenter is 20–30°C, and the fermentation time is 70–80 h, with stirring maintained throughout the fermentation process. After fermentation, the cells were collected and extracted with ethanol at a pH of 2–3 to obtain a pigment solution.

[0024] 2) Bamboo and wood pretreatment: After removing the outer green layer and inner wax layer from the raw bamboo, it is processed into bamboo strips. The bamboo and wood are steamed and then bleached with a bleaching agent. After bleaching, they are drained. During this process, existing mechanical methods can be used to remove the outer green layer and inner wax layer to prevent the wax from affecting the adhesion and penetration of the dye. The bamboo and wood are steamed over low heat for 1-2 hours. During the steaming process, the oil and impurities on the surface of the bamboo strips are decomposed, and the internal fibers of the bamboo strips become soft, further preparing them for dyeing. The temperature and time control in this process are very important, otherwise it will affect the subsequent dyeing effect. Preferably, the bleaching agent is a 10-15% hydrogen peroxide solution, and the bleaching time is 0.5-1 hour. Using an appropriate concentration of hydrogen peroxide for bleaching can fully bleach the bamboo strips, reduce the negative impact of the original attached impurities on subsequent dyeing, and minimize the corrosiveness of high concentration hydrogen peroxide on the bamboo strips, thus reducing the impact on the stability of the bamboo strip structure.

[0025] 3) Bamboo and wood modification treatment: The bamboo strips treated in step 1) are modified with an alkaline solution with a mass fraction of 0.4-1.0%. Ultrasonic assistance is used during the treatment process. The treatment temperature is 65-75℃ and the treatment time is 20-40 minutes. After the treatment is completed, the bamboo strips are frozen. After the freezing treatment is completed, the bamboo strips are thawed and cleaned for later use. Under these conditions, a good modification effect was achieved. The reason is speculated to be that the combination of low-concentration alkali solution and ultrasonic assistance, performed within a predetermined temperature range, altered the internal pit structure of the bamboo, opening more pores and improving the traditional difficulty of fluid dyes flowing through closed pores. This significantly improved permeability and effectively enhanced the flow and penetration of fluid dyes within the bamboo. Furthermore, the freezing treatment caused ice crystals to form inside the bamboo, puncturing the inner walls of the pits and creating cracks or fissures, allowing fluid dyes to exchange and interact between adjacent pits, further improving the uniformity of dyeing. This entire modification process altered the internal structure of the bamboo, making the pit structure more complex. During subsequent dyeing and heat treatment, this effectively reduced the backflow of dyeing solution within the bamboo, further improving the color-fixing effect. Thorough cleaning was performed to reduce the corrosive effects of prolonged alkali residue on the bamboo and to facilitate subsequent dyeing. In this process, the ultrasonic power was preferably 1000–1200W. The reason is speculated to be that excessively strong ultrasonic output can easily damage the internal pores, causing damage to the pore channels and affecting the permeability, which in turn affects the dyeing and color fixing effect. On the other hand, too low ultrasonic power cannot achieve the effect of synergistic action with alkali solution.

[0026] In this process, the freezing treatment involves freezing the bamboo strips at -20 to -40°C for 20 to 40 hours, and the thawing treatment is carried out at 10 to 30°C. It is important to note that slow freezing is used, rather than rapid freezing. During slow freezing, ice crystals grow fully, which facilitates the formation of larger ice crystals. This, in turn, facilitates the formation of pores or cracks on the pit walls, further enabling the dye liquor to enter and flow through.

[0027] 4) Dyeing Treatment: Immerse the bamboo strips treated in step 3) in the dyeing solution. Maintain the temperature at 30–50°C and the pressure inside the tank at 0.2–0.6 MPa during the dyeing process, for 3–5 hours. Preferably, a heating and pressurizing method is used for dyeing, allowing the external dye solution to penetrate the bamboo strips at a certain rate and slowly seep through the pits. This gradual process helps to further improve the uniformity of dyeing. Furthermore, it is crucial to strictly maintain the temperature within this range; excessively low temperatures are not conducive to thorough dyeing, while excessively high temperatures can easily destroy the biological pigments. Adjust the pH of the dyeing solution to 2–6 and maintain a stable pH during the dyeing process. This allows for control of color changes by adjusting the pH during dyeing, making the operation convenient and better meeting practical needs.

[0028] 5) Drying treatment: Remove the bamboo strips treated in step 4), wash off any surface stains, and then dry them. A preferred method is to dry the washed bamboo strips at a constant temperature of 100–130°C until the moisture content is 8–10%.

[0029] The technology of this invention utilizes biological pigments to achieve excellent uniformity in dyeing treated bamboo and wood materials, ensures dyeing depth, provides good color fixation, and is environmentally friendly and safe, making it more suitable for applications in kitchenware, children's toys, and other fields.

[0030] Example 1

[0031] A method for staining bamboo and wood using biological pigments includes the following steps:

[0032] 1) Preparation of bio-pigments: *Gibberellic acid bacillus* (Gibberellic acid bacillus) was activated and inoculated into a fermenter for further fermentation. After fermentation, the pigment solution was extracted for later use. The liquid culture medium in the fermenter consisted of the following raw materials by weight: 200 g / L potato, 20 g / L glucose, 2.5 g / L yeast extract, and 0.005 g / L KH₂PO₄. The pH of the liquid culture medium was adjusted to 7.0. The inoculum size in the fermenter was 5%, the fermentation temperature was 26℃, and the fermentation time was 75 h.

[0033] 2) Bamboo and wood pretreatment: After removing the green bamboo and the waxy layer inside the bamboo, the raw bamboo is processed into bamboo strips with a thickness of 8mm; the bamboo and wood are steamed and then bleached with a 12% hydrogen peroxide solution for 0.8 hours. After bleaching, the bamboo and wood are drained.

[0034] 3) Bamboo and wood modification treatment: The bamboo strips treated in step 1) are modified with an alkaline solution with a mass fraction of 0.6%. In actual operation, the sodium hydroxide solution needs to cover the bamboo strips. Ultrasonic assistance is used in the treatment process. The ultrasonic power is 1200W, the treatment temperature is 70℃, and the treatment time is 30min. After the treatment, the bamboo strips are frozen at -30℃ for 28h. After the freezing treatment, the bamboo strips are thawed and cleaned for use.

[0035] 4) Dyeing Treatment: The bamboo strips treated in step 3) were immersed in the dyeing solution. A stepped heating and pressurization method was used for dyeing. The initial temperature was maintained at 30℃ and the initial pressure at 0.2MPa for 1.5 hours. After further heating and pressurization, the temperature was increased to 40℃ and the pressure to 0.4MPa for 1.5 hours. Finally, the temperature was increased to 50℃ and the pressure to 0.6MPa for 1.5 hours. Multiple control experiments were conducted during the dyeing process, with pH values ​​of 2, 3, 4, 5, and 6.

[0036] 5) Drying treatment: Take out the bamboo strips treated in step 4), wash off the surface dye, and dry the washed bamboo strips at a constant temperature of 110℃ until the moisture content is about 9%.

[0037] Comparative Example 1

[0038] A method for staining bamboo and wood using biological pigments includes the following steps:

[0039] 1) Preparation of bio-pigments: *Gibberellic acid bacillus* (Gibberellic acid bacillus) was activated and inoculated into a fermenter for further fermentation. After fermentation, the pigment solution was extracted for later use. The liquid culture medium in the fermenter consisted of the following raw materials by weight: 200 g / L potato, 20 g / L glucose, 2.5 g / L yeast extract, and 0.005 g / L KH₂PO₄. The pH of the liquid culture medium was adjusted to 7.0. The inoculum size in the fermenter was 5%, the fermentation temperature was 26℃, and the fermentation time was 75 h.

[0040] 2) Bamboo and wood pretreatment: After removing the green bamboo and the waxy layer inside the bamboo, the raw bamboo is processed into bamboo strips with a thickness of 8mm; the bamboo and wood are steamed and then bleached with a 12% hydrogen peroxide solution for 0.8 hours. After bleaching, the bamboo and wood are drained.

[0041] 3) Dyeing treatment: The bamboo strips treated in step 2) were immersed in the dyeing solution. A stepped heating and pressurization method was used for dyeing. The initial temperature was maintained at 30℃ and the initial pressure at 0.2MPa for 1.5 hours. After further heating and pressurization, the temperature was increased to 40℃ and the pressure to 0.4MPa for 1.5 hours. Finally, the temperature was increased to 50℃ and the pressure to 0.6MPa for 1.5 hours. Multiple control experiments were conducted during the dyeing process, with pH values ​​of 2, 3, 4, 5, and 6.

[0042] 4) Drying treatment: Take out the bamboo strips treated in step 3), wash off the surface dye, and dry the washed bamboo strips at a constant temperature of 110℃ until the moisture content is about 9%.

[0043] Comparative Example 2

[0044] A method for staining bamboo and wood using biological pigments includes the following steps:

[0045] 1) Preparation of bio-pigments: *Gibberellic acid bacillus* (Gibberellic acid bacillus) was activated and inoculated into a fermenter for further fermentation. After fermentation, the pigment solution was extracted for later use. The liquid culture medium in the fermenter consisted of the following raw materials by weight: 200 g / L potato, 20 g / L glucose, 2.5 g / L yeast extract, and 0.005 g / L KH₂PO₄. The pH of the liquid culture medium was adjusted to 7.0. The inoculum size in the fermenter was 5%, the fermentation temperature was 26℃, and the fermentation time was 75 h.

[0046] 2) Bamboo and wood pretreatment: After removing the green bamboo and the waxy layer inside the bamboo, the raw bamboo is processed into bamboo strips with a thickness of 8mm; the bamboo and wood are steamed and then bleached with a 12% hydrogen peroxide solution for 0.8 hours. After bleaching, the bamboo and wood are drained.

[0047] 3) Bamboo and wood modification treatment: The bamboo strips treated in step 1) are modified with an alkaline solution with a mass fraction of 2.5%. In actual operation, the sodium hydroxide solution needs to cover the bamboo strips. Ultrasonic assistance is used in the treatment process. The power of the ultrasonic wave is 2000W, the treatment temperature is 70℃, and the treatment time is 10min. After the treatment, the bamboo strips are frozen. The freezing treatment is to quickly freeze the bamboo strips to -35℃ and store them for 28h. After the freezing treatment, the bamboo strips are thawed and cleaned for use. The thawing treatment is carried out at 20℃.

[0048] 4) Dyeing treatment: Immerse the bamboo strips treated in step 3) in the dyeing solution and perform dyeing treatment using a stepped heating and pressurization method. During the dyeing process, maintain the initial temperature at 30℃ and the initial pressure at 0.2MPa for 1.5 hours; after heating and pressurizing, maintain the temperature at 40℃ and the pressure at 0.4MPa for 1.5 hours; after further heating and pressurizing, maintain the temperature at 50℃ and the pressure at 0.6MPa for 1.5 hours. The pH value during the dyeing process is 2.

[0049] 5) Drying treatment: Take out the bamboo strips treated in step 4), wash off the surface dye, and dry the washed bamboo strips at a constant temperature of 110℃ until the moisture content is about 9%.

[0050] Comparative Example 3

[0051] A method for staining bamboo and wood using biological pigments includes the following steps:

[0052] 1) Preparation of bio-pigments: *Gibberellic acid bacillus* (Gibberellic acid bacillus) was activated and inoculated into a fermenter for further fermentation. After fermentation, the pigment solution was extracted for later use. The liquid culture medium in the fermenter consisted of the following raw materials by weight: 200 g / L potato, 20 g / L glucose, 2.5 g / L yeast extract, and 0.005 g / L KH₂PO₄. The pH of the liquid culture medium was adjusted to 7.0. The inoculum size in the fermenter was 5%, the fermentation temperature was 26℃, and the fermentation time was 75 h.

[0053] 2) Bamboo and wood pretreatment: After removing the green bamboo and the waxy layer inside the bamboo, the raw bamboo is processed into bamboo strips with a thickness of 8mm; the bamboo and wood are steamed and then bleached with a 12% hydrogen peroxide solution for 0.8 hours. After bleaching, the bamboo and wood are drained.

[0054] 3) Bamboo and wood modification treatment: The bamboo strips treated in step 1) were modified with 0.6% alkali solution. The treatment temperature was 70℃ and the treatment time was 30min. After the treatment, the bamboo strips were frozen at -30℃ for 28h. After the freezing treatment, the bamboo strips were thawed and cleaned for later use.

[0055] 4) Dyeing treatment: Immerse the bamboo strips treated in step 3) in the dyeing solution and perform the dyeing treatment using a constant temperature and pressure method. The dyeing temperature is 50℃, the dyeing pressure is 0.5MPa, and the dyeing time is 4.5h. During the dyeing process, the pH value is maintained at 2.

[0056] 5) Drying treatment: Take out the bamboo strips treated in step 4), wash off the surface dye, and dry the washed bamboo strips at a constant temperature of 110℃ until the moisture content is about 9%.

[0057] The uniformity of dyeing was observed in bamboo strips dyed in Examples 1 and 1-3. The processed bamboo strips were then horizontally cut into multiple thin strips approximately 1 mm thick, and the color difference (ΔE) and uniformity between the strips were observed. Furthermore, a color-fixing effect test was conducted on bamboo strips dyed in Examples 1 and 1-3. Each bamboo strip was boiled in water for 1 hour and then left at room temperature for 60 days to observe the degree of fading. The color of the product from Example 1 under different pH conditions is shown in Table 1. The results of dyeing uniformity and color-fixing effect for the product from Example 1 at pH 2 and the products obtained from Examples 1-3 are shown in Table 2.

[0058] Table 1

[0059] pH 2 3 4 5 6 Product Color brick red brownish-yellow Maroon brick brown dark brown

[0060] Table 2

[0061]

[0062] As shown in Table 1, adjusting the pH during the dyeing process, combined with other dyeing and drying conditions, can result in different colors for the final product. In practical applications, the appropriate method can be chosen based on the specific needs.

[0063] As shown in Table 2, the thin bamboo strips obtained in Example 12 exhibit a relatively bright brick red color with minimal color difference between them, indicating that the dye can penetrate well into the inner layer of the bamboo strips, and the dye is evenly distributed across different locations on the same thin bamboo strip. In contrast, in Comparative Example 1, the color of each thin bamboo strip shows a visible gradient distribution from the surface to the inner layer, and the dye distribution is uneven across different locations on the same bamboo strip, indicating that pre-dyeing modification treatment of the bamboo strips is extremely important. In Comparative Example 2, the color difference between the thin bamboo strips is significant, and there are instances of dye concentration or blank areas on different locations on the same thin bamboo strip, indicating that control of modification conditions is crucial. Improper control of conditions results in extremely poor dyeing effects. It is speculated that improper treatment may further exacerbate the blockage of the internal pore channels of the bamboo strips, reducing permeability and preventing the flow of dye within the bamboo strips. In Comparative Example 3, no ultrasonic-assisted treatment was performed, and the dyeing was carried out using a constant temperature and pressure method during drying. The results showed that the dye could not penetrate well into the inner layer of the bamboo strips, the dyeing uniformity was poor in the middle and inner layers, and there was fading. The color fixation effect was poor, indicating that ultrasonic-assisted treatment and dyeing by increasing temperature and pressure are key steps in the technical solution of the present invention.

[0064] In summary, the product prepared by this invention has excellent dyeing uniformity, good color fixation effect, good permeability, and is safe and environmentally friendly, making it well applicable to kitchenware, children's toys and other fields.

[0065] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for dyeing bamboo and wood using biological pigments, characterized in that, Includes the following steps: 1) Preparation of bio-pigment: The color-changing bacteria are activated and inoculated into a fermenter for further fermentation. After fermentation, the pigment liquid is extracted for later use. The color-changing bacteria is *Gibberel labaccata*. 2) Bamboo and wood pretreatment: After removing the green bamboo and the waxy layer inside the bamboo, the raw bamboo is processed into bamboo strips; the bamboo and wood are steamed and then bleached with bleaching agent. After bleaching, they are taken out and drained. 3) Bamboo and wood modification treatment: The bamboo strips treated in step 1) are modified with an alkaline solution with a mass fraction of 0.4~1.0%. Ultrasonic assistance is used in the treatment process. The power of the ultrasonic wave is 1000~1200W. The treatment temperature is 65~75℃ and the treatment time is 20~40min. After the treatment, the bamboo strips are frozen. After the freezing treatment, they are thawed and cleaned for later use. 4) Dyeing treatment: Immerse the bamboo strips treated in step 3) into the dyeing solution. During the dyeing process, maintain the temperature at 30~50℃, the pressure inside the tank at 0.2~0.6MPa, and the dyeing time at 3~5h. 5) Drying treatment: Take out the bamboo strips that have been treated in step 4), wash off the surface dye, and then dry them.

2. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 1), the liquid culture medium in the fermenter includes the following raw materials in parts by weight: 200 g / L of potatoes, 20 g / L of glucose, 2.5 g / L of yeast extract, 0.005 g / L of KH2PO4, with the remainder being distilled water, and the pH of the liquid culture medium is adjusted to 7.

0.

3. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 1), the inoculum amount in the fermenter is 4-6%, the fermentation temperature is 20-30℃, the fermentation pH is 4-6, and the fermentation time is 70-80h.

4. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 2), the thickness of the bamboo strips is 6~10mm.

5. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 2), the bleaching agent is a hydrogen peroxide solution with a mass fraction of 10-15%, and the bleaching time is 0.5-1h.

6. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 3), the freezing treatment involves freezing the bamboo strips at -20 to -40°C for 20 to 40 hours.

7. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 4), the dyeing process is carried out by heating and pressurizing.

8. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 4), the pH of the staining solution is adjusted to 2-6 and the pH of the staining solution is kept stable during the staining process.

9. The method for staining bamboo and wood using biological pigments according to claim 1, characterized in that, In step 5), the cleaned bamboo strips are dried at a constant temperature of 100~130℃ until the moisture content is 8~10%.

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