Dyeing method for industrially preparing gambiered canton gauze silk

Abstract

The invention belongs to the field of textile dyeing and finishing, and relates to a dyeing method for industrially preparing gambiered canton gauze silk, which comprises the following steps: 1) dip dyeing and hot drying of silk fabric (silk white body); (2) carrying out color fixation treatment on the dip-dyed / heat-dried fabric by utilizing enzyme treatment liquid; (3) the fabric obtained in the step (2) is sequentially and repeatedly subjected to the step (1) and the step (2) for 1-3 times, and a dyed product of the gambiered canton gauze silk is obtained. The method is simple and easy to implement, high in efficiency and controllable in cost, and can be used for industrially preparing gambiered canton silk products.

Description

Technical Field

[0001] The invention belongs to the field of textile dyeing and finishing, and relates to a dyeing method for industrially preparing ramie silk. Background Art

[0002] The ramie silk originated in the Lingnan region of my country. It is one of China's national geographical landmark products and a classic silk product that is deeply loved by domestic consumers. The ramie silk adopts ecological and environmentally friendly dyeing and finishing technology. The fabric has a unique double-sided different color structure and excellent wearing performance.

[0003] The dyeing process of ramie silk is very complicated. The traditional process relies entirely on manual work, which is carried out in sequence: crushing ramie tubers → preparing ramie dye liquid → dyeing silk → sun exposure → repeating the dyeing / sun exposure process about 30 times → obtaining the sun-drying ramie product. In the preparation process of ramie silk, dyeing / sun exposure is the most laborious and time-consuming process, and is largely restricted by geographical and climatic conditions, making it difficult for ramie silk to achieve cross-regional and industrial production. The product obtained after 30 times of dyeing / sun exposure is a sun-drying ramie fabric, which can be directly used to make ready-made clothes. The purpose of repeated dyeing / sun exposure is to make the ramie pigment more and more firmly deposited on the front side of the silk fabric (sun exposure side), forming a double-sided different color effect (dark color on the front side, light color on the back side), and making the finished fabric have better color fastness. Silk that is repeatedly dyed with ramie pigment without sunlight exposure does not have the double-sided color difference effect, has very low color fastness, and the pigment easily falls off the fabric, making it difficult to meet the requirements of double-sided color difference and color fastness for ready-made clothing. This limitation makes it difficult to industrially produce ramie silk, mainly due to the lack of color fixation technology, and it is difficult for industrial methods to achieve the color fixation effect of sunlight exposure. Without a color fixation process, it is difficult to achieve continuous deposition of ramie pigment on the surface of the fabric by repeatedly dyeing / drying with machinery and equipment, because during dyeing, the previously deposited pigment will dissolve in the dye bath and fall off the fabric. In order to solve the dyeing and fixing problems in the preparation process of ramie silk, the industry has adopted some alternative methods, such as using simulated sunlight (ultraviolet / infrared lamp) to treat ramie pigment dyed fabrics for fixing (patent WO2018040887A1, patent CN206157370U), pre-treating silk fabrics with chemical auxiliaries (study on the new process of dyeing and finishing of ramie dyes and imitation Xiangyun yarn. Master's thesis of Zhejiang University of Technology, 2022), and treating with silicone resin after dyeing (CN202011557401.9). However, these methods have some problems. For example, the first method has complex equipment and high energy consumption, and the latter two use chemical synthetic auxiliaries, which are out of the concept of pure natural, healthy and environmentally friendly ramie silk and it is difficult to obtain the effect of double-sided different colors of traditional ramie silk, which is difficult to be accepted by the industry and consumers. Therefore, the primary technical problem to be solved in the industrial preparation of ramie silk is the problem of dyeing and fixing during repeated dyeing. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for dyeing silk fabrics with yam pigments with high efficiency and high fastness by utilizing natural biological enzymes.

[0005] In order to solve the above technical problems, the present invention provides a dyeing method for industrially preparing ramie silk, comprising the following steps:

[0006] 1) Dyeing and heat drying of silk fabrics (silk blank):

[0007] Dyeing: immerse the silk fabric in a yam dye solution with a concentration of 5g / L to 20g / L and a temperature of 50±2°C for a dyeing time of 5±1s to obtain the dyed fabric;

[0008] Heat drying: heat drying the dyed fabric using heat drying equipment; during heat drying, the heating temperature of the upper side of the fabric (becoming the front side after dyeing) is adjusted to 100°C to 150°C (preferably 115 to 150°C), and the heating temperature of the lower side of the fabric (becoming the reverse side after dyeing) is adjusted to 50°C to 100°C (preferably 62 to 100°C), and the temperature difference between the upper side and the lower side of the fabric is ≥50°C; the heat drying time is 2±0.1min, and the first dyed / heat dried fabric is obtained;

[0009] Repeat the soaking and hot drying process for the fabric which has been soaked and hot-dried for the first time; the number of repetitions is 4 times, that is, the number of soaking and hot-dried processes is 5 times in total, and the fabric which has been soaked and hot-dried repeatedly is obtained;

[0010] Note: When drying, always put the fabric into the drying equipment with the same side facing the same side, that is, the front side is always facing up and the back side is facing down;

[0011] 2) Fixation of dyed fabrics:

[0012] Dissolve the biological enzyme preparation in pure water to prepare an enzyme treatment solution with a concentration of 0.1 g / L to 1.5 g / L;

[0013] According to the weight ratio of enzyme treatment liquid: repeated dyeing / heat drying fabric = 40% to 100%, the enzyme treatment liquid is sprayed on the front side of the repeatedly dyed / heat dried fabric by using a spray device, and then rolled into a roll, and a fixation reaction is carried out for at least 5 hours under the environmental conditions of temperature of 35° C. to 45° C. and relative humidity of 85% to 100%;

[0014] Finally, heat-dry at 120±5℃ for 90±3s;

[0015] It is explained that the above-mentioned fixation reaction time generally does not exceed 24 hours (that is, it can be controlled to be 5 to 24 hours); otherwise it will only lead to a decrease in production efficiency;

[0016] 3) Repeat steps 1) and 2) for 1 to 3 times, i.e., the dyeing / heat drying in step 1) and the color fixing treatment in step 2) are performed 2 to 4 times in total, to obtain ramie silk (ramie silk dyeing product).

[0017] As an improvement of the dyeing method for industrially preparing ramie silk of the present invention:

[0018] The biological enzyme preparation is catechol oxidase (also known as polyphenol oxidase, tyrosinase).

[0019] As a further improvement of the dyeing method for industrially preparing ramie silk of the present invention:

[0020] In step 1), the concentration of the yam dye solution is 11-20 g / L.

[0021] As a further improvement of the dyeing method for industrially preparing ramie silk of the present invention, in step 2):

[0022] The mass concentration of the enzyme treatment solution is 0.5g / L~1.0g / L.

[0023] Enzyme treatment solution: repeated dyeing / heat drying fabric = 60-85% by weight;

[0024] The fixation reaction temperature is 37-42°C, the fixation reaction relative humidity is 88-95%, and the fixation reaction time is 13h-24h.

[0025] As a further improvement of the dyeing method for industrially preparing ramie silk of the present invention, the number of repetitions in step 3) is 2 to 3 times, that is, the number of times of dyeing / heat drying in step 1) - color fixing in step 2) is 3 to 4 times in total.

[0026] The invention aims at the defects of the repeated dyeing process in the industrial preparation process of ramie silk products, such as complex equipment, high energy consumption, use of chemical synthetic products, unsatisfactory double-sided different color effect, low color fastness, etc., and provides a method for dyeing silk with ramie pigment with high efficiency and high fastness by using natural biological enzymes.

[0027] The principle of the present invention is that under the action of catechol oxidase, the condensed tannin pigments of dioscorea with catechol structure are polymerized or catalytically oxidized into quinone substances, so that the water solubility of dioscorea pigment is reduced, thereby improving the color fastness of the fabric dyed with dioscorea pigment, and further realizing efficient dyeing on the basis of good color fixation effect. And the capillary effect generated by the temperature difference on both sides of the fabric during hot drying (the side with high temperature dries faster, and the side with low temperature dries slower) is used to make the dioscorea pigment migrate more to the front side of the fabric, so as to achieve the double-sided different color effect.

[0028] Compared with other methods, the present invention has the following beneficial technical effects:

[0029] First, it does not use sunlight or simulated sunlight for color fixation, avoiding reliance on the natural environment and expensive simulated sunlight equipment. It also avoids the problem of products that are not natural, environmentally friendly, or authentic, which is caused by the current large-scale use of chemical synthetic products for dyeing and color fixation in the industry.

[0030] Secondly, the dyeing process using this method is highly efficient, the number of immersion dyeing times is small, and the product has a good color fixing effect.

[0031] Third, the dyeing and fixing method is simple, low in energy consumption, and can be easily implemented on conventional dyeing and finishing equipment.

[0032] In summary, the present invention provides a dyeing method for industrially preparing ramie silk. The silk fabric impregnated with ramie dye solution is dried under the condition of upper and lower temperature difference, and the color fixation treatment is repeated for a certain number of times using polyphenol oxidase, and after repeated multiple times, the dyed fabric obtains a higher color depth, better color fastness and double-sided different color effect. The method is simple and easy to implement, has high efficiency and controllable cost, and can be used for industrially preparing ramie silk products. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0034] Fresh yam root pieces were crushed to a particle size of less than 5 mm, and water was added to the yam root pieces at a weight ratio of fresh weight of yam root pieces: water = (1.4±0.5):1, and the yam root pieces were extracted at 55±5°C with stirring for 0.5 to 3 hours, and then the extract was filtered with a 50-mesh sieve to obtain yam dye solution, and the mass concentration of the yam dye solution was tested with a refractometer.

[0035] In general:

[0036] Extract at 60℃ for 2 hours to obtain a yam dye solution with a concentration of about 18.8g / L;

[0037] Extraction was carried out at 55°C for 2 hours to obtain a yam dye solution with a concentration of about 15.2 g / L;

[0038] Extraction was carried out at 50°C for 1 hour to obtain a yam dye solution with a concentration of about 11.0 g / L;

[0039] Extraction was performed at 50°C for 0.5 hours to obtain a yam dye solution with a concentration of about 7.4 g / L.

[0040] Catechol oxidase (also known as polyphenol oxidase, tyrosinase, EC 1.10.3.1, activity of 1000U / mg) can be purchased from Guangdong Mingtong Biotechnology Co., Ltd.; horseradish peroxidase (EC 1.11.1.7, activity of 250U / mg) and laccase (EC 1.10.3.2, activity of 50U / mg) can be purchased from Hangzhou Mick Chemical Instrument Co., Ltd.

[0041] The following cases all use the same silk white fabric, electric spinning, weight 130g / m 3 .

[0042] Embodiment 1, a kind of industrial preparation ramie silk dyeing method, carry out the following steps in sequence:

[0043] 1) Dyeing and heat drying of silk fabrics:

[0044] Dyeing: Immerse the silk blank fabric in a yam dye solution with a mass concentration of 15.2 g / L and a temperature of 50±2°C for 5 seconds, take it out, and obtain the dyed fabric;

[0045] Heat drying: put the dyed fabric into the heat drying equipment, adjust the heating temperature of the upper side of the fabric (becoming the front side after dyeing) to 130℃, and adjust the heating temperature of the lower side of the fabric (becoming the reverse side after dyeing) to 75℃, that is, the temperature difference between the upper side and the lower side of the fabric is 55℃, heat dry the fabric for 2 minutes under the above heating conditions to obtain the first dip-dyed / heat-dried fabric;

[0046] Repeat the soaking and hot drying process for 4 times on the fabric after the first soaking and hot drying process; that is, the total number of soaking and hot drying processes is 5 times, and the soaking and hot drying process is repeated for 5 times.

[0047] Note: When drying, always put the fabric into the drying equipment with the same side facing the same side, that is, the front side is always facing up and the back side is facing down.

[0048] 2) Fixation of dyed fabrics:

[0049] Catechol oxidase was dissolved in pure water to prepare an enzyme treatment solution with a concentration of 0.7 g / L.

[0050] According to the weight ratio of enzyme treatment liquid: repeated impregnation / heat drying fabric = 60%, the enzyme treatment liquid was sprayed on the front side of the fabric that was repeatedly impregnated / heat dried 5 times by using a spray device, and then rolled into a roll, and the color fixing reaction was carried out for 16 hours under the environmental conditions of temperature 40°C and relative humidity 95%;

[0051] Finally, heat-dry at 120°C for 90s;

[0052] 3) Repeat steps 1) and 2) for 3 times, i.e., the total number of color fixation treatments of step 1) dyeing / heat drying---step 2) is 4 times, and the dyed product of ramie silk is obtained.

[0053] Embodiments 2 to 4 are different from Embodiment 1 in that the process parameters thereof are changed (as described in Table 1 below), and the rest are the same as Embodiment 1; thus, Embodiments 2 to 4 are obtained accordingly.

[0054] Table 1

[0055]

[0056]

[0057] The dyed ramie silk products obtained in Examples 1 to 4 were tested and analyzed:

[0058] The color depth (K / S value) of the front and back sides of the dyed camisole silk products was tested using a conventional spectrophotometer; the color fastness to washing of the dyed camisole silk products was tested using AATCC 61-2003 "Color fastness to home and commercial washing: rapid method"; and the color fastness to dry and wet rubbing of the front side of the fabric was tested using GB / T 3920-2008 "Textiles - Tests for color fastness - color fastness to rubbing". The test results are shown in Table 2.

[0059] Table 2

[0060]

[0061] turn out:

[0062] The K / S values ​​of the front and back sides of the camisole dyed fabric obtained in Example 1 are 8.3 and 3.4 respectively, with obvious double-sided different color effects, and the front color depth reaches the color depth of traditional sun-drying camisole fabrics. The color fastness to washing of the camisole dyed fabric is 4-5; the color fastness to dry friction and wet friction are 3-4 and 3 respectively, reaching or even exceeding the color fastness of traditional sun-drying camisole fabrics (the color fastness to washing is generally 4, the color fastness to dry friction is generally 3-4, and the color fastness to wet friction is generally 2-3).

[0063] The K / S values ​​of the front and back sides of the camisole dyed fabric obtained in Example 2 are 8.1 and 3.2 respectively, which has an obvious double-sided different color effect, and the front color depth reaches the color depth of traditional sun-dried camisole fabric. The color fastness to washing of the camisole dyed fabric is 4-5; the color fastness to dry friction and wet friction is 4 and 3 respectively, reaching or even exceeding the color fastness of traditional sun-dried camisole fabric.

[0064] The K / S values ​​of the front and back sides of the camisole dyed fabric obtained in Example 3 are 7.8 and 3.1 respectively, which has an obvious double-sided different color effect, and the color depth of the front side reaches the color depth of traditional sun-dried camisole fabric. The color fastness to washing of the camisole dyed fabric is 4-5; the color fastness to dry friction and wet friction is 3-4 and 3 respectively, reaching or even exceeding the color fastness of traditional sun-dried camisole fabric.

[0065] The K / S values ​​of the front and back sides of the camisole dyed fabric obtained in Example 4 are 6.5 and 3.0 respectively, which has an obvious double-sided different color effect, and the front color depth reaches the color depth of traditional sun-dried camisole fabric. The color fastness to washing of the camisole dyed fabric is level 4; the color fastness to dry friction and wet friction are level 3-4 and level 3 respectively, reaching the color fastness of traditional sun-dried camisole fabric.

[0066] It can be seen that the ramie silk dyed fabric obtained by the processing method of the present invention has double-sided different colors and good color fastness.

[0067] Comparative Example 1: Compared with Example 2, the concentration of the yam dye solution was changed to 4.2 g / L; the rest was the same as Example 2.

[0068] Comparative Example 2, relative to Example 2, the heating temperature of the front side of the fabric is changed to 130°C, and the heating temperature of the back side of the fabric is changed to 110°C, that is, the temperature difference between the front side and the back side of the fabric is changed to 20°C; the rest is the same as Example 2.

[0069] Comparative Example 3: Compared with Example 2, the concentration of catechol oxidase was changed to 0.05 g / L, and the rest was the same as Example 2.

[0070] Comparative Example 4: Compared with Example 2, the fixing reaction temperature was changed to 30°C, and the rest was the same as Example 2.

[0071] Comparative Example 5: Compared with Example 2, the relative humidity of the fixation reaction was changed to 75%, and the rest was the same as Example 2.

[0072] Comparative Example 6: Compared with Example 2, the fixing reaction time was changed to 3.5 h, and the rest was the same as Example 2.

[0073] Comparative Example 7, referring to patent CN202011557401.9 (natural dyeing method using yam), execute steps (1) to (3) in Example 1 of the patent to obtain yam dyed fabric.

[0074] Comparative Example 8: Compared with Example 2, the catechol oxidase treatment solution was replaced with a horseradish peroxidase treatment solution, and the concentration and dosage of the treatment solution remained unchanged. The rest was the same as Example 2.

[0075] Comparative Example 9: Compared with Example 2, the catechol oxidase treatment solution was replaced with a laccase treatment solution, the concentration and dosage of the treatment solution remained unchanged, and the rest was the same as Example 2.

[0076] The dyed ramie silk products obtained in Comparative Examples 1 to 9 were tested and analyzed (the test and analysis methods were the same as above), and the test results are shown in Table 3 below.

[0077] Table 3

[0078]

[0079] In Comparative Example 1, the concentration of the yam dye solution does not meet the requirements of the present invention, and the K / S value of the front side of the dyed fabric obtained is only 4.1, which is significantly less than the front color depth of the traditional sun-dried yam fabric (K / S value above 6.0), and the front color is too light, which is obviously different from the appearance of the traditional sun-dried yam fabric. It can be seen that if the concentration of the yam dye used is too low, the yam pigment deposited on the surface of the fabric is less, resulting in a lighter color of the fabric, and ultimately a yam yarn silk dyeing product similar to the traditional sun-dried yam fabric cannot be obtained.

[0080] Comparative Example 2, the temperature difference between the fabric front side and the fabric back side temperature does not meet the requirements of the present invention, the K / S value of the dyed fabric front obtained is 6.8, the back K / S value is 6.4, the front and back K / S value difference is only 0.4, which is much smaller than the color depth difference of the front and back sides of the traditional sun-drying ramie fabric (the K / S value difference is more than 3.0). The obtained dyed fabric double-sided heterochromatic effect is not obvious, which is obviously different from the appearance characteristics of the traditional sun-drying ramie fabric. This is because the temperature difference between the front and back sides is small, the drying rates on both sides are almost the same, the capillary effect is not significant, and the amount of ramie pigment migration to the fabric front side is less. It can be seen from this that if the hot baking temperature and the temperature difference on both sides of the fabric front and back do not meet the requirements of the present invention, the ramie yarn silk dyeing product similar to the traditional sun-drying ramie fabric can not be obtained finally.

[0081] Comparative Example 3, the concentration of catechol oxidase does not meet the requirements of the present invention. The K / S value of the front side of the dyed fabric obtained is 5.3, and the K / S value of the back side is 2.1. The front color is too light, which is obviously different from the appearance of the traditional sun-dried ramie fabric. The washing color fastness of the dyed fabric is 3 levels, the dry friction color fastness is 2-3 levels, and the wet friction color fastness is 2 levels, which are obviously worse than the traditional sun-dried ramie fabric. The color depth and color fastness of the obtained dyed fabric are obviously worse than the sun-dried ramie fabric prepared by the traditional process. This is because the concentration of catechol oxidase is low, and only part of the ramie pigment is polymerized or catalytically oxidized to quinone substances. It can be seen from this that if the concentration of the catechol oxidase used is too low, the ramie silk dyeing product with good color depth and color fastness can not be obtained in the end.

[0082] Comparative Example 4, the fixation reaction temperature of catechol oxidase is significantly lower than the requirements of the present invention. The K / S value of the front side of the dyed fabric obtained is 5.7, and the K / S value of the back side is 2.8. The front color is lighter, which is obviously different from the appearance of the traditional sun-dried ramie fabric. The water washing color fastness of the dyed fabric is 3 levels, the dry friction color fastness is 2-3 levels, and the wet friction color fastness is 2 levels, which are significantly worse than the traditional sun-dried ramie fabric. The color depth and color fastness of the obtained dyed fabric are significantly worse than the sun-dried ramie fabric prepared by the traditional process. This is because the temperature range for the best activity of catechol oxidase is 35-45°C. If the temperature is too low or too high, the activity of catechol oxidase will be inhibited, the catalytic effect will be reduced, and the catalytic reaction of ramie pigment will be adversely affected. It can be seen from this that if the catalytic reaction temperature (fixation reaction temperature) of the catechol oxidase used is too low, the ramie silk dyeing product with good color depth and color fastness cannot be obtained in the end.

[0083] Comparative Example 5, the relative humidity of the catechol oxidase fixation reaction conditions is significantly lower than the requirements of the present invention, the K / S value of the front side of the dyed fabric obtained is 5.6, the K / S value of the back side is 2.5, the front color is lighter, and it is obviously different from the appearance of the traditional sun-dried ramie fabric. The washing color fastness of the dyed fabric is 3-4 grades, the color fastness to dry rubbing is 3 grades, and the color fastness to wet rubbing is 2 grades, which is basically half a grade lower than the traditional sun-dried ramie fabric. The color depth and color fastness of the obtained dyed fabric are significantly worse than the sun-dried ramie fabric prepared by the traditional process. This is because the environmental humidity is low, the enzyme solution on the fabric is easy to evaporate, the cloth surface is easy to dry, the catechol oxidase activity is reduced, the catechol oxidase catalytic reaction effect is affected, and the ramie pigment reacted on the cloth surface is greatly reduced. It can be seen from this that if the relative humidity condition of the catechol oxidase used is too low, the ramie silk dyeing product with good color depth and color fastness can not be obtained in the end.

[0084] Comparative Example 6, the fixation reaction time of catechol oxidase is significantly lower than the requirement of the present invention, the K / S value of the front side of the dyed fabric obtained is 5.2, the K / S value of the back side is 2.1, the front color is lighter, and it is obviously different from the appearance of the traditional sun-dried ramie fabric. The washing color fastness of the dyed fabric is 2-3 grades, the color fastness to dry rubbing is 2 grades, and the color fastness to wet rubbing is 2 grades, which are significantly worse than the traditional sun-dried ramie fabric. The color depth and color fastness of the obtained dyed fabric are significantly worse than the sun-dried ramie fabric prepared by the traditional process. This is because the time for the catechol oxidase to catalyze the reaction of ramie pigment is too short, and only a small amount of ramie pigment reacts on the cloth surface. It can be seen from this that if the catalytic reaction time of the catechol oxidase used is too short, the ramie silk dyeing product with good color depth and color fastness can not be obtained in the end.

[0085] Comparative Example 7, the K / S value of the front side of the dyed fabric obtained is 6.7, and the K / S value of the back side is 6.7. There is no color difference between the front and back sides, which is obviously different from the double-sided heterochromatic effect of the traditional sun-drying fabric. The color fastness of the dyed fabric to washing is 1-2 levels, the color fastness to dry friction is 1 level, and the color fastness to wet friction is 1 level, and the color fastness is very poor. This is because the method lacks the key step of color fixation. Even if the patent performs repeated immersion / heat drying processes 30 times, the dyed fabric cannot obtain good color fastness. Because heat drying alone cannot make the yam pigment firmly bonded to the fabric surface. It can be seen that the color fixation step is indispensable during repeated dyeing.

[0086] Comparative Example 8, the K / S value of the front side of the dyed fabric obtained is 5.2, and the K / S value of the back side is 2.6. The color of the front side of the fabric is obviously lighter than the color of the front side of the dyed product of the ramie silk obtained in Example 2, and it is not as deep as the color of the traditional sun-dried ramie fabric. The color fastness of the dyed fabric to washing is grade 2, the color fastness to dry friction is grade 2, and the color fastness to wet friction is grade 1, and the color fastness is very poor. This is because the horseradish peroxidase used for color fixation can also catalyze the polymerization of phenolic substances such as phenol, although the literature reports that it can also catalyze the polymerization of phenolic substances such as phenol, but in fact it may have a certain selectivity for the catalysis of the substrate, and the catalytic activity of the ramie tannin pigment, a substance with a bisphenol structure, is relatively low, and the color fixation effect cannot be achieved. It can be seen that the use of catechol oxidase in the color fixation step is very critical.

[0087] Comparative Example 9, the K / S value of the front side of the dyed fabric obtained is 5.9, and the K / S value of the back side is 3.0. The color depth of the front side of the fabric is also significantly different from the dyed product of the ramie silk obtained in Example 2, and is not as good as the traditional sun-dried ramie fabric. The water washing color fastness of the dyed fabric is level 3, the dry friction color fastness is level 2-3, and the wet friction color fastness is level 2, and the color fastness is relatively poor. This is because the laccase activity (the laccase activity used in this example is 50U / mg, which is a product with higher activity among commercially available laccase products) is much lower than that of catechol oxidase. Under the same enzyme concentration conditions, the effect of catalyzing the tannin pigment with a catechol structure is obviously not as good as that of catechol oxidase. Although it also has a more obvious color fixation effect, it has a significant difference relative to the color fixation effect of catechol oxidase. It can be seen that when repeatedly dyeing, catechol oxidase reagents are indispensable in the color fixation step.

[0088] Finally, it should be noted that the above examples are only some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and there are many variations. All variations that can be directly derived or associated with the content disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. A dyeing method for industrially preparing ramie silk, characterized in that The steps include: 1) Dyeing and heat drying of silk fabrics: Dyeing: immerse the silk fabric in a yam dye solution with a concentration of 5g / L to 20g / L and a temperature of 50±2°C for a dyeing time of 5±1s to obtain the dyed fabric; Heat drying: Heat drying the dyed fabrics with heat drying equipment; during heat drying, adjust the heating temperature of the upper side of the fabric to 100℃~150℃, the heating temperature of the lower side of the fabric to 50℃~100℃, and the temperature difference between the upper side and the lower side of the fabric is ≥50℃; the heat drying time is 2±0.1min, and the first dyed / heat dried fabric is obtained; Repeat the soaking and hot drying of the fabric after the first soaking and hot drying; The number of repetitions is 4, and the fabric is repeatedly dip-dyed / heat-dried; 2) Fixation of dyed fabrics: Dissolve the biological enzyme preparation in pure water to prepare an enzyme treatment solution with a concentration of 0.1 g / L to 1.5 g / L; According to the weight ratio of enzyme treatment liquid: repeated dyeing / heat drying fabric = 40% to 100%, the enzyme treatment liquid is sprayed on the front side of the repeatedly dyed / heat dried fabric by using a spray device, and then rolled into a roll, and a fixation reaction is carried out for at least 5 hours under the environmental conditions of temperature of 35° C. to 45° C. and relative humidity of 85% to 100%; Finally, heat-dry at 120±5℃ for 90±3s; 3) Repeat steps 1) and 2) for 1 to 3 times to obtain the fabric obtained in step 2) to obtain the ramie silk.

2. The method for industrially preparing ramie silk dyeing according to claim 1, characterized in that: The biological enzyme preparation is catechol oxidase.

3. The method for industrially preparing ramie silk dyeing according to claim 2, characterized in that: In step 1), the concentration of the yam dye solution is 11-20 g / L.

4. The method for industrially preparing ramie silk dyeing according to claim 3, characterized in that In step 2): The mass concentration of the enzyme treatment solution is 0.5g / L~1.0g / L. Enzyme treatment solution: repeated dyeing / heat drying fabric = 60-85% by weight; The fixation reaction temperature is 37-42°C, the fixation reaction relative humidity is 88-95%, and the fixation reaction time is 13h-24h.

5. The method for industrially preparing ramie silk dyeing according to any one of claims 1 to 4, characterized in that: The number of repetitions in step 3) is 2 to 3 times.

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