Printing method for extracting color paste from green persimmons

Abstract

The invention discloses a printing method of green persimmon extracted color paste, and relates to the technical field of natural plant dye printing. According to the method, immature green persimmons are used as raw materials, cell structures of the green persimmons are destroyed through cellulase and ultrasonic treatment, the extraction rate of tannin is increased, then tannin is further purified through an ultrafiltration membrane and macroporous resin, and purified tannin is obtained. Laccase is used for catalyzing tannin polymerization, the polymerization degree of tannin is improved, and then the tannin is used for preparing color paste for silk-screen printing and manufacturing cloth printed in a persimmon color paste style. The dye disclosed by the invention is from natural plants, the product is high in affinity to a human body, non-toxic and harmless, and the prepared printing is unique in style and relatively high in color fastness to washing, color fastness to rubbing and color fastness to light.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of natural plant dye printing, and more particularly to a printing method of persimmon extract color paste. BACKGROUND

[0002] Persimmon dyeing process is a traditional plant dyeing technology using unripe persimmons as raw materials, and its core mechanism relies on the high content of condensed tannins in persimmons. The phenolic hydroxyl and ortho-benzene diol groups in the molecular structure of this type of tannin give it strong complexing ability, which can form stable combinations with metal ions, proteins and cellulose molecules, thus realizing the dyeing function.

[0003] In the traditional process, the persimmons need to be crushed and then naturally fermented for about one to three years. During the fermentation process, the sugar and pectin in the persimmons are decomposed, and at the same time, the tannic acid is gradually oxidized and condensed to form a high molecular compound that is difficult to dissolve. Although it has good dyeing effect, the fermentation time is too long and is not suitable for industrial production. In modern research, various chemical methods are generally used to extract tannins from persimmons. For example, in patent CN106008616A, butanediol is used to extract tannins from persimmons, and the product purity reaches more than 98%. Patent CN109593108A discloses a method for extracting and separating high-purity persimmon tannins, which is obtained by raw material treatment, extraction filtrate, concentration of filtrate, gelatin precipitation, precipitation washing, tannin extraction, dissolution desalting, purification and drying. Although the above two methods can efficiently extract tannins from persimmons, the molecular weight of tannins extracted directly by solvent is relatively low, and the binding ability with fibers is weak, resulting in poor dyeing effect for printing.

[0004] Therefore, how to provide a printing method of persimmon extract color paste with short process time, good color paste stability and high printing color fastness is a problem that needs to be solved by those skilled in the art. SUMMARY

[0005] Therefore, the present application provides a printing method of persimmon extract color paste, which destroys the cell structure of persimmons by cellulase and ultrasonic treatment to improve the extraction rate of tannins. Then the tannins are further purified by ultrafiltration membrane and macroporous resin to obtain purified tannins. The tannins are polymerized by laccase catalysis to improve the polymer, and then the color paste is prepared for silk screen printing to make cloth with persimmon color paste style printing.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0007] The present application provides a printing method of persimmon extract color paste, which specifically includes the following steps:

[0008] S1 persimmon crude extraction

[0009] Select immature green persimmon, remove enzyme damaged parts, wash with clean water, slice, low temperature drying, crushing, obtain green persimmon powder; green persimmon powder is added with water stirring, and pH is adjusted by citric acid, cellulase is added, constant temperature water bath oscillation, after reaction is completed, cellulase is inactivated by heating, enzyme treatment liquid is obtained; anhydrous ethanol is added in enzyme treatment liquid, ultrasonic treatment is carried out; after treatment is completed, centrifugation is carried out, green persimmon crude extract is obtained.

[0010] Its beneficial effects are that cellulase is used to decompose cellulose in cell wall, destroy cell structure, and fully release tannin in green persimmon; then ultrasonic treatment is further used to destroy cell structure, increase tannin extraction rate.

[0011] S2 tannin purification

[0012] Green persimmon crude extract is filtered by ultrafiltration membrane; filtrate is reduced pressure concentrated, separated by macroporous resin adsorption, eluent is reduced pressure concentrated, freeze-dried, tannin powder is obtained.

[0013] Its beneficial effects are that residual macromolecular impurities are removed by ultrafiltration membrane; then tannin is further purified by selective adsorption of macroporous resin.

[0014] S3 laccase treatment

[0015] Tannin powder is dissolved in deionized water, pH is adjusted by citric acid, laccase is added, constant temperature oscillation is carried out, laccase treatment liquid is obtained after reaction is completed and inactivation by heating.

[0016] Its beneficial effects are that laccase catalyzes tannin oxidation and crosslinking, forms polymer with larger molecular weight, and enhances wash fastness and color fastness of color paste.

[0017] S4 screen printing

[0018] Laccase treatment liquid is concentrated, pH is adjusted by adding sodium citrate; then sodium alginate is added, viscosity is adjusted, color paste is prepared; color paste is printed on fabric by screen printing process, forms printing, and printed fabric is obtained.

[0019] S5 sun reduction and mordanting

[0020] Printed fabric is placed under sunlight for sunning, sun-dried fabric is neutral soaped, then mordanting agent is used for mordanting, fabric is sun-dried again, neutral soaped, and fabric with persimmon color paste style printing is obtained.

[0021] The low-temperature drying temperature in step S1 is 50°C; the material-liquid ratio of the green tomato powder and water is 1g:10-20mL; the citric acid is used to adjust the pH to 4.0-6.0; the cellulase activity is 5000-10000U / g, and the addition amount is 0.5%-1% of the mass of the green tomato powder; the constant temperature water bath oscillation temperature is 50-55°C, the time is 1-2h; the temperature of the heating inactivation is 70°C, and the time is 30min.

[0022] In step S1, the volume ratio of anhydrous ethanol to enzyme treatment solution is 6:4-7:3; the power of the ultrasonic treatment is 300W, and the time is 60-100 min; the centrifugal speed is 5000-6000 r / min.

[0023] The average molecular weight cutoff of the ultrafiltration membrane in the ultrafiltration in step S2 is 10 kDa, and the pressure is 0.35 MPa; the filtrate is concentrated under reduced pressure to 1 / 10 of its original volume.

[0024] The macroporous resin adsorption separation in step 2 uses S-8 macroporous resin, the sample flow rate is 1 BV / h, and 70%-80% ethanol is used as the eluent, and the elution flow rate is 1 BV / h.

[0025] In step S3, the solid-liquid ratio of the tannin powder to deionized water is 20-40 g:1 L; the citric acid is used to adjust the pH to 4.5-5.5; the mass ratio of the tannin powder to laccase is 40-80:1, and the specification of the laccase is 5000 U / g; the temperature of the constant temperature oscillation is 40° C., and the time is 2-3 hours; the temperature-raising inactivation is 70° C. for 30 minutes.

[0026] The concentration in step S4 is concentration under reduced pressure to 1 / 10 of the original volume; the pH adjustment is adjusting the pH to 4-6; and the viscosity adjustment is adjusting the viscosity to 8000-12000 mPa·s.

[0027] The number of days for drying in step S5 is 1-5 days; the mordant is one or a combination of wood ash juice, alum solution, copper sulfate solution, and ferrous sulfate solution.

[0028] It can be seen from the above technical solution that, compared with the prior art, the present invention discloses a printing method for extracting color paste from green persimmon, which has the following beneficial effects:

[0029] (1) By combining enzymatic hydrolysis and ultrasonic treatment, the cell wall structure of green persimmon was fully destroyed and the extraction rate of tannin was increased.

[0030] (2) Using membrane technology and macroporous resin, impurities in the crude extract of green persimmon are fully removed to obtain tannins with higher purity to meet the needs of textile dyeing.

[0031] (3) Using laccase to catalyze tannin polymerization, improving polymer, thus improving the washing fastness and color fastness of tannin, and obtaining good dyeing effect. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0033] Embodiment 1

[0034] A printing method of green persimmon extraction color syrup, specifically comprising the following steps:

[0035] S1 Green persimmon rough extraction

[0036] Select immature green persimmons, remove enzyme-damaged parts, wash with clean water, slice, dry at 50℃, crush, and obtain green persimmon powder.

[0037] Add 10L of water to 1kg of green persimmon powder, stir, adjust the pH to 5.0 by citric acid, add 10g of cellulase with activity of 5000U / g, and oscillate in a 50℃ constant temperature water bath for 2h. After the reaction is completed, increase the temperature to 70℃ for 30min to inactivate the cellulase, and obtain an enzyme treatment liquid.

[0038] Add anhydrous ethanol in a proportion of 6:4 of anhydrous ethanol to the enzyme treatment liquid, perform ultrasonic treatment with a power of 300W for 60min, and then centrifuge at 5000r / min to obtain the supernatant, which is the green persimmon rough extraction liquid.

[0039] S2 Tannin purification

[0040] Filter the green persimmon rough extraction liquid by using an ultrafiltration membrane with an average molecular weight cut-off of 10kDa at a pressure of 0.35MPa, and then concentrate the filtrate under reduced pressure to 1 / 10 of the original volume.

[0041] Adsorb the filtrate concentrate by using an S-8 type macroporous resin with a loading flow rate of 1BV / h, use 70% ethanol as an eluent with an elution flow rate of 1BV / h, concentrate the eluent under reduced pressure, and freeze-dry to obtain tannin powder.

[0042] S3 Laccase treatment

[0043] Dissolve 20g of tannin powder in 1L of deionized water, adjust the pH to 4.5 by citric acid, add 0.5g of laccase with activity of 5000U / g, oscillate at 40℃ for 2h, increase the temperature to 70℃ after the reaction is completed to inactivate for 30min, and obtain a laccase treatment liquid.

[0044] S4 screen printing

[0045] The laccase treatment solution is reduced pressure concentrated to 1 / 10 of the original volume, sodium citrate is added to adjust the pH to 5.0; then sodium alginate is added, and the viscosity is adjusted to 8000 mPa·s to prepare the color paste; the color paste is printed on the cloth by a screen printing process to form prints, and printed cloth is obtained;

[0046] S5 sun drying reduction and mordanting

[0047] The printed cloth is placed in the sun for 3 days, and the dried cloth is subjected to neutral soaping, and then subjected to mordanting with wood ash water, and twice drying and neutral soaping to obtain cloth with persimmon color paste style prints.

[0048] Example 2

[0049] A printing method of persimmon extract color paste, specifically comprising the following steps:

[0050] S1 persimmon rough extraction

[0051] Unripe persimmons are selected, damaged parts are removed, washed with water, sliced, dried at 50°C, and crushed to obtain persimmon powder.

[0052] 1 kg of persimmon powder is stirred with 20 L of water, and the pH is adjusted to 6.0 with citric acid, 5 g of cellulase with an activity of 10000 U / g is added, and the mixture is oscillated in a constant temperature water bath at 50°C for 2 h. After the reaction is completed, the temperature is raised to 70°C for 30 min to inactivate the cellulase, and an enzyme treatment solution is obtained.

[0053] Anhydrous ethanol is added in a ratio of 7:3 with the enzyme treatment solution, and ultrasonic treatment is performed at a power of 250 W for 90 min. After the treatment is completed, centrifugation is performed at 6000 r / min, and the supernatant is obtained, which is the persimmon rough extract.

[0054] S2 tannin purification

[0055] The persimmon rough extract is filtered by an ultrafiltration membrane with an average molecular weight cut-off of 10 kDa at a pressure of 0.35 MPa, and then the filtrate is reduced pressure concentrated to 1 / 10 of the original volume.

[0056] The filtrate concentrate is adsorbed by an S-8 type macroporous resin at a loading flow rate of 1 BV / h, and 80% ethanol is used as an eluent at an elution flow rate of 1 BV / h. The eluent is reduced pressure concentrated and freeze-dried to obtain a tannin powder.

[0057] S3 laccase treatment

[0058] 20 g tannin powder was dissolved in 1 L deionized water, citric acid was added to adjust the pH to 4.5, 0.7 g of laccase with activity of 5000 U / g was added, and constant temperature oscillation was carried out at 40℃ for 3 h. After the reaction was completed, the temperature was raised to 70℃ for 30 min to inactivate, and a laccase treatment liquid was obtained;

[0059] S4 silk screen printing

[0060] The laccase treatment liquid was concentrated under reduced pressure to 1 / 10 of the original volume, and sodium citrate was added to adjust the pH to 4.5. Then sodium alginate was added to adjust the viscosity to 12000 mPa·s, and a color paste was prepared. The color paste was printed on the cloth by a silk screen printing process to form a print, and a printed cloth was obtained.

[0061] S5 sun drying reduction and mordanting

[0062] The printed cloth was placed in the sun for 1 day, and the dried cloth was subjected to neutral soaping, and then was washed with a mordanting agent of wood ash water, and was dried and soaped again to obtain a cloth with persimmon color paste style printing.

[0063] Example 3

[0064] A printing method of persimmon extract color paste, specifically comprising the following steps:

[0065] S1 persimmon rough extraction

[0066] Unripe persimmons were selected, the enzyme-variant damaged parts were removed, washed with clean water, sliced, dried at 50℃, and then pulverized to obtain persimmon powder.

[0067] 1 kg of persimmon powder was added with 15 L of water and stirred, and the pH was adjusted to 4.0 by citric acid. 5 g of cellulase with activity of 5000 U / g was added, and constant temperature water bath oscillation was carried out at 55℃ for 1 h. After the reaction was completed, the temperature was raised to 70℃ for 30 min to inactivate the cellulase, and an enzyme treatment liquid was obtained.

[0068] Anhydrous ethanol was added in a proportion of 6:4 of anhydrous ethanol to enzyme treatment liquid, and ultrasonic treatment was carried out at a power of 300 W for 80 min. After the treatment was completed, centrifugation was carried out at 5000 r / min, and the supernatant was taken as the persimmon rough extraction liquid.

[0069] S2 tannin purification

[0070] The persimmon rough extraction liquid was filtered by an ultrafiltration membrane with an average molecular weight cut-off of 10 kDa at a pressure of 0.35 MPa, and then the filtrate was concentrated under reduced pressure to 1 / 10 of the original volume.

[0071] The filtrate concentrate was adsorbed by S-8 macroporous resin, the loading flow rate was 1 BV / h, 70% ethanol was used as eluent, the elution flow rate was 1 BV / h, the eluent was concentrated under reduced pressure, and the tannin powder was obtained by freeze-drying.

[0072] S3 laccase treatment

[0073] 30 g of tannin powder was dissolved in 1 L of deionized water, citric acid was added to adjust the pH to 5.5, 0.5 g of laccase with an activity of 5000 U / g was added, and the solution was oscillated at 40°C for 2 h. After the reaction was completed, the temperature was increased to 70°C for 30 min to inactivate the laccase, and a laccase treatment solution was obtained.

[0074] S4 screen printing

[0075] The laccase treatment solution was concentrated under reduced pressure to 1 / 10 of the original volume, and sodium citrate was added to adjust the pH to 5.0. Then, sodium alginate was added to adjust the viscosity to 12000 mPa·s, and a color paste was prepared. The color paste was printed on the fabric by screen printing process to form a print, and a printed fabric was obtained.

[0076] S5 sun reduction and mordanting

[0077] The printed fabric was placed in the sun for 4 days, and the dried fabric was subjected to neutral soaping and then mordanting with a copper sulfate solution. After two times of drying and neutral soaping, a fabric with persimmon color paste style print was obtained.

[0078] Example 4

[0079] A printing method of persimmon extract color paste, specifically comprising the following steps:

[0080] S1 persimmon rough extraction

[0081] Unripe persimmons were selected, the enzyme-damaged parts were removed, washed with water, sliced, dried at 50°C, and then pulverized to obtain persimmon powder.

[0082] 1 kg of persimmon powder was added to 10 L of water and stirred, and the pH was adjusted to 4.5 by citric acid. 5 g of cellulase with an activity of 5000 U / g was added, and the solution was oscillated in a water bath at 50°C for 2 h. After the reaction was completed, the temperature was increased to 70°C for 30 min to inactivate the cellulase, and an enzyme treatment solution was obtained.

[0083] Anhydrous ethanol was added in a ratio of 6:4 to the enzyme treatment solution, and ultrasonic treatment was performed at a power of 300 W for 100 min. After the treatment was completed, the solution was centrifuged at 5000 r / min, and the supernatant was obtained, which was the persimmon rough extract.

[0084] S2 tannin purification

[0085] The green persimmon crude extract solution is filtered by using an ultrafiltration membrane with an average molecular weight cut-off of 10 kDa at a pressure of 0.35 MPa, and then the filtrate is concentrated under reduced pressure to 1 / 10 of the original volume.

[0086] The filtrate concentrate is adsorbed by using an S-8 type macroporous resin, the loading flow rate is 1 BV / h, 70% ethanol is used as the eluent, the elution flow rate is 1 BV / h, the eluent is concentrated under reduced pressure, and then freeze-drying is performed to obtain a tannin powder.

[0087] S3 Laccase treatment

[0088] 40 g of the tannin powder is dissolved in 1 L of deionized water, citric acid is added to adjust the pH to 4.5, 0.5 g of laccase with an activity of 5000 U / g is added, constant temperature oscillation is performed at 40°C for 3 h, after the reaction is completed, the temperature is increased to 70°C for 30 min of inactivation, and a laccase treatment solution is obtained;

[0089] S4 Screen printing

[0090] The laccase treatment solution is concentrated under reduced pressure to 1 / 10 of the original volume, sodium citrate is added to adjust the pH to 6.0, then sodium alginate is added, and the viscosity is adjusted to 12000 mPa·s to prepare a color paste; the color paste is printed on the fabric by using a screen printing process to form a print, and a printed fabric is obtained.

[0091] S5 Sunlight reduction and mordanting

[0092] The printed fabric is placed in the sunlight for 5 days, the dried fabric is subjected to neutral soaping, and then is subjected to mordanting with a ferrous sulfate solution, and is subjected to secondary drying, neutral soaping, to obtain a fabric with persimmon color paste style printing.

[0093] Comparative Example 1

[0094] A printing method of a green persimmon extraction color paste, specifically comprising the following steps:

[0095] S1 Green persimmon extraction

[0096] Unripe green persimmons are selected, damaged parts are removed, washed with clean water, sliced, dried at 50°C, and then pulverized to obtain green persimmon powder.

[0097] 1 kg of the green persimmon powder is stirred with 15 L of water, the pH is adjusted to 4.0 by using citric acid, 5 g of cellulase with an activity of 5000 U / g is added, constant temperature water bath oscillation is performed at 55°C for 1 h, after the reaction is completed, the temperature is increased to 70°C for 30 min of treatment to inactivate the cellulase, and an enzyme treatment solution is obtained.

[0098] Add anhydrous ethanol in the proportion of 6:4 with enzyme treatment solution, ultrasonic treatment with power of 300 W for 80 min, centrifuge at 5000 r / min after treatment, and take the supernatant as the crude persimmon extract.

[0099] S2 tannin purification

[0100] The crude persimmon extract is filtered by an ultrafiltration membrane with an average molecular weight cut-off of 10 kDa and a pressure of 0.35 MPa, and then the filtrate is concentrated under reduced pressure to 1 / 10 of the original volume.

[0101] The concentrated filtrate is adsorbed by S-8 macroporous resin with a loading flow rate of 1 BV / h, and 70% ethanol is used as the eluent with an elution flow rate of 1 BV / h. The eluent is concentrated under reduced pressure and freeze-dried to obtain tannin powder.

[0102] S3 screen printing

[0103] 30 g of tannin powder is dissolved in 100 mL of water, and sodium citrate is added to adjust the pH to 5.0. Then sodium alginate is added to adjust the viscosity to 12000 mPa·s to prepare a color paste. The color paste is printed on the fabric by screen printing process to form prints, and printed fabric is obtained.

[0104] S4 sun reduction and mordanting

[0105] The printed fabric is placed in the sun for 4 days, and the dried fabric is washed with neutral soap, then washed with mordanting agent copper sulfate solution, and dried twice with neutral soap to obtain fabric with persimmon color paste style prints.

[0106] Performance evaluation

[0107] The color fastness to washing, color fastness to rubbing, and color fastness to light of the products in the examples and comparative examples are tested according to GB / T3921-2008, GB / T3920-2008, and GB / T8427-2019, and the results are as follows:

[0108]

[0109] From the data in the table, it can be seen that Comparative Example 1 (without laccase) has significantly decreased color fastness to washing / rubbing (ΔE>4, wet rubbing≤2 grade) due to insufficient aggregation of tannin, confirming that laccase oxidation can enhance the tannin-fiber binding force.

[0110] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Modifications of these embodiments will occur to persons of skill in the art, and, while certain modifications are discussed, it is desired to be protected in accordance with the spirit and scope of the application. Therefore, the application is not limited to the specific embodiments shown and described, but only by the scope of the appended claims, unless otherwise specified.

Claims

1. A printing method for extracting color paste from green persimmon, characterized in that: The specific steps include: S1 green tomato extract Select unripe green tomatoes, remove the parts damaged by enzyme changes, wash with clean water, slice, dry at low temperature, and crush to obtain green tomatoes powder; Green persimmon powder was added with water and stirred, and the pH was adjusted with citric acid. Cellulase was added and shaken in a constant temperature water bath. After the reaction was completed, the temperature was raised to inactivate the cellulase to obtain an enzyme treatment solution; Anhydrous ethanol was added to the enzyme treatment solution and ultrasonic treatment was performed; after the treatment, the solution was centrifuged to obtain a crude green persimmon extract; S2 Tannin Purification The green persimmon crude extract is filtered using an ultrafiltration membrane; the filtrate is concentrated under reduced pressure, separated by adsorption using a macroporous resin, the eluate is concentrated under reduced pressure, and freeze-dried to obtain tannin powder; S3 laccase treatment Tannin powder is dissolved in deionized water, citric acid is added to adjust the pH, laccase is added, and the mixture is shaken at a constant temperature. After the reaction is completed, the temperature is raised to inactivate the mixture, thereby obtaining a laccase treatment solution. S4 Screen Printing The laccase treatment solution is concentrated, and sodium citrate is added to adjust the pH; sodium alginate is then added to adjust the viscosity to obtain a color paste; the color paste is printed on fabric through a screen printing process to form a print, thereby obtaining a printed fabric; S5 drying and mordanting The printed fabric is placed in the sun to dry, the dried fabric is neutrally soaped, then mordant-washed, dried a second time, and neutrally soaped to obtain fabric with persimmon color paste style printing.

2. The printing method of the green persimmon extraction paste according to claim 1, characterized in that: The temperature of the low-temperature drying in step S1 is 50°C.

3. The printing method of extracting color paste from green persimmon according to claim 1, characterized in that: The material-liquid ratio of the green persimmon powder and water in step S1 is 1 g: 10-20 mL; The citric acid is used to adjust the pH to 4.0-6.0; The cellulase activity is 5000-10000 U / g, and the added amount is 0.5%-1% of the mass of the green persimmon powder; The constant temperature water bath oscillation temperature is 50-55°C, and the time is 1-2h; The temperature for inactivation was 70°C and the time was 30 min.

4. The printing method of extracting color paste from green persimmon according to claim 1, characterized in that: The volume ratio of anhydrous ethanol to enzyme treatment solution in step S1 is 6:4 to 7:3; The power of the ultrasonic treatment is 300W, and the time is 60 to 100 minutes; The centrifugal speed is 5000-6000 r / min.

5. The printing method of extracting color paste from green persimmon according to claim 1, characterized in that: The average molecular weight cut-off of the ultrafiltration membrane in the ultrafiltration in step S2 is 10 kDa and the pressure is 0.35 MPa; The filtrate was concentrated under reduced pressure to 1 / 10 of its original volume.

6. The printing method of extracting color paste from green persimmon according to claim 1, characterized in that: The macroporous resin adsorption separation in step 2 uses S-8 macroporous resin, the sample flow rate is 1 BV / h, and 70%-80% ethanol is used as the eluent, and the elution flow rate is 1 BV / h.

7. The printing method of extracting color paste from green persimmon according to claim 1, characterized in that: In step S3, the material-liquid ratio of the tannin powder to deionized water is 20-40 g:1 L; The citric acid is used to adjust the pH to 4.5-5.5; The mass ratio of the tannin powder to the laccase is 40-80:1, and the specification of the laccase is 5000 U / g; The constant temperature oscillation temperature is 40°C and the time is 2 to 3 hours; The temperature-raising inactivation is carried out at 70° C. for 30 min.

8. The printing method of extracting color paste from green persimmon according to claim 1, characterized in that: The concentration in step S4 is concentrated under reduced pressure to 1 / 10 of the original volume; The pH adjustment is to adjust the pH to 4-6; The viscosity adjustment is to adjust the viscosity to 8000-12000 mPa·s.

9. The printing method of extracting color paste from green persimmon according to claim 1, characterized in that: The number of days for drying in step S5 is 1-5 days; The mordant is one or a combination of wood ash juice, alum solution, copper sulfate solution, and ferrous sulfate solution.

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