Calcining method of dry paint

Abstract

The invention belongs to the technical field of traditional Chinese medicine calcining, and particularly relates to a dry paint calcining method. The calcining method of the dry paint comprises the following steps: (1) crushing and sieving a dry paint raw material; (2) the sieved dry paint is put into a medicine calcining furnace, a sealing cover is fastened, and a 1 cm hole is reserved in the center of the sealing cover; (3) starting a medicine calcining furnace for calcining; (4) shutting down the medicine calcining furnace, and taking out the dry paint; the calcining temperature in the step (3) is 350 + / -3 DEG C to 380 + / -3 DEG C. The calcined dry lacquer obtained by the dry lacquer calcining method provided by the invention is high in urushiol content, the total ash content does not exceed 8%, the acid-insoluble ash content does not exceed 5%, and the total ash content and the acid-insoluble ash content all meet the specified standard in Chinese Pharmacopoeia.

Description

Technical Field

[0001] The invention belongs to the technical field of traditional Chinese medicine calcination, and particularly relates to a method for calcining dry lacquer. Background Art

[0002] Raw lacquer is the earliest known and used natural paint and a vital raw material for modern industry, agriculture, national defense, science, technology, and civilian applications. Lacquer flowers, rich in nectar, are also a key source of nectar. Lacquer oil, processed from lacquer seeds, is both edible and a paint raw material. The leaves, flowers, roots, bark, fruit, dried lacquer, and heartwood of the lacquer tree are all used medicinally. Dried lacquer, listed in the Chinese Pharmacopoeia, is pungent, warm, and toxic. It enters the spleen meridian and has the properties of dispersing blood stasis, eliminating stagnation, and killing insects. It is used to treat amenorrhea, fatigue, blood addiction, and abdominal pain caused by parasites.

[0003] The main components of raw lacquer are urushiol, laccase, gum (polysaccharide), glycoprotein, and water. Urushiol accounts for 40-80%, gum (polysaccharide) 5-7%, glycoprotein 2-5%, and laccase <1.0%. Traditional calcination methods suffer from inconsistent processes, difficulty controlling the quality of the calcined lacquer, and complex operations.

[0004] As disclosed in Chinese patent CN116850215A, a method for preparing calcined dry lacquer combining modern large-scale equipment with traditional methods is used. The method adopts a dark calcination method to calcine dry lacquer. First, the dry lacquer is placed in a calcining machine hopper, then the hopper cover and the hopper are sealed, and then the calcining machine is started to forge. After forging, it is cooled to room temperature, and finally the medicinal material is taken out to obtain calcined dry lacquer. The invention adopts modern calcining equipment to forge, and is surrounded by heating. The temperature is more uniform. By setting the temperature control and the time relationship, a large number of medicinal materials can be prepared in a disposable manner, and the occurrence of temperature unevenness caused by heating the bottom of a traditional iron pan is avoided. The processing temperature control is more accurate, and the obtained dry lacquer product quality is uniform, and the cross section is bright dark brown or tan, and is densely covered with honeycomb-like small holes. It not only meets the needs of modern mechanized large-scale production, but also effectively saves calcination time, ensuring that the processed product is more uniform and effective. However, the quality uniformity and its urushiol content of the invention are yet to be improved.

[0005] For example, Chinese patent CN113876806A discloses a method for carbonizing and calcining traditional Chinese medicine at high temperatures, comprising the following steps: professionals remove the rough bark of lacquer trees and harvest them; sun-dry the harvested lacquer resin, clean it, and screen out impurities for later use; prepare a dedicated high-temperature stove, a dedicated special sealed high-temperature pot, and other auxiliary equipment; place the raw lacquer into the dedicated special sealed high-temperature pot, ensuring that the pot is tightly sealed; use waste wood and scraps as fuel to heat the dedicated special sealed high-temperature pot over high heat to over 300°C; wait for the black and white smoke to disappear, and after 6-8 hours, a block-shaped black product is obtained; continue heating for 10-12 hours to obtain a silvery-white, odorless, completely carbonized product; and after calcination, use a dedicated cooling device to quickly cool the product. This method eliminates harmful substances such as tar from the carbonized voids, resulting in highly active and thoroughly carbonized traditional Chinese medicine with remarkable carbonization results. However, the invention has a complicated process and is difficult to ensure uniformity of quality.

[0006] Therefore, it is urgent to study a kind of efficient and controllable dry lacquer calcining method. Summary of the Invention

[0007] In view of the shortcomings of the prior art, the present invention provides a method for calcining dry lacquer. The calcined dry lacquer obtained by the method not only has a high urushiol content but also has a total ash content of no more than 8% and an acid-insoluble ash content of no more than 5%, both of which meet the standards specified in the Chinese Pharmacopoeia.

[0008] To achieve the above purpose, the present invention adopts the following technical solutions:

[0009] In one aspect, the present invention provides a method for calcining dry lacquer, comprising the following steps:

[0010] (1) crushing the dry paint raw materials and sieving;

[0011] (2) Place the sieved dry paint into the calcining furnace, fasten the sealing cover, and leave a hole with an inner diameter of 1 cm in the center of the sealing cover;

[0012] (3) starting the calcining furnace for calcining;

[0013] (4) Shut down the calcining furnace and take out the dried paint.

[0014] Preferably, the sieving mesh number in step (1) is 10-15 mesh, preferably 10 mesh.

[0015] Preferably, the calcining furnace described in step (2) is a temperature-controlled, rolling, sealed calcining furnace.

[0016] Preferably, the calcination temperature in step (3) is 350±3°C-380±3°C; the calcination time is 1.5-2.5h; and the calcination environment is sealed and the oxygen content does not exceed 2%.

[0017] Preferably, the calcination temperature in step (3) is 360±3° C., and the calcination time is 2 h.

[0018] Preferably, in the calcination of step (3), the calcining furnace is rolled once when the calcination reaches 15-20 minutes, the calcination furnace is rolled once when the calcination continues for 30-35 minutes, and the calcination furnace is rolled once when the calcination continues for 45-50 minutes, until no smoke is emitted from the sealing cover hole.

[0019] Preferably, in the calcination of step (3), the calcining furnace is rolled once after 15 minutes of calcination, the calcining furnace is rolled once after 35 minutes of calcination, and the calcining furnace is rolled once after 45 minutes of calcination, until no smoke is emitted from the sealing cover hole.

[0020] The present invention also provides dry varnish prepared by the above preparation method, wherein the total ash content of the dry varnish is ≤6%, and the acid-insoluble ash content is ≤2%.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The dry lacquer calcining method provided by the present invention has better quality stability and higher urushiol content, the total ash content of the dry lacquer does not exceed 8%, the acid-insoluble ash content does not exceed 5%, and the dry lacquer calcining method provided by the present invention is simple and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The color changes of the raw lacquer, the purchased calcined lacquer, and the calcined lacquer in Example 1 after 24h of acetone extraction;

[0024] Figure 2 This is the chromatogram of urushiol from raw dried lacquer;

[0025] Figure 3 Chromatogram of purchased calcined urushiol;

[0026] Figure 4 This is the chromatogram of the calcined dry urushiol in Example 1. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is described clearly and completely below with specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present invention. The materials, reagents, etc. used, unless otherwise specified, are reagents and materials available from commercial sources.

[0028] Example 1

[0029] A method for calcining dry lacquer is as follows:

[0030] (1) Grind the dry paint raw materials and sieve through 10 mesh;

[0031] (2) Place the sieved dry paint into the calcining furnace, fasten the sealing cover, and leave a 1 cm hole in the center of the sealing cover;

[0032] (3) Start the calcining furnace and calcine at a temperature of 350±3°C. After calcining for 15 minutes, rotate the calcining furnace once. Continue calcining for 35 minutes and rotate the calcining furnace once. Then, calcine for 45 minutes and rotate the calcining furnace once until no smoke is emitted from the sealing cover hole. The whole calcining process takes 2 hours.

[0033] (4) Turn off the calcining furnace and let it cool to room temperature, then take out the dried paint.

[0034] Example 2

[0035] A method for calcining dry lacquer is as follows:

[0036] (1) Grind the dry paint raw materials and sieve through 15 mesh;

[0037] (2) Place the sieved dry paint into the calcining furnace, fasten the sealing cover, and leave a 1 cm hole in the center of the sealing cover;

[0038] (3) Start the calcining furnace and calcine at a temperature of 360±3°C. After calcining for 20 minutes, rotate the calcining furnace once. Continue calcining for 30 minutes and rotate the calcining furnace once. Then, calcine for 50 minutes and rotate the calcining furnace once until no smoke is emitted from the sealing cover hole. The whole calcining process takes 2.5 hours.

[0039] (4) Turn off the calcining furnace and let it cool to room temperature, then take out the dried paint.

[0040] Example 3

[0041] A method for calcining dry lacquer is as follows:

[0042] (1) Grind the dry paint raw materials and sieve through 10 mesh;

[0043] (2) Place the sieved dry paint into the calcining furnace, fasten the sealing cover, and leave a 1 cm hole in the center of the sealing cover;

[0044] (3) Start the calcining furnace and calcine at a temperature of 370±3°C. After calcining for 15 minutes, rotate the calcining furnace once. Continue calcining for 35 minutes and rotate the calcining furnace once. Then, calcine for 45 minutes and rotate the calcining furnace once until no smoke is emitted from the sealing cover hole. The whole calcining process takes 1.5 hours.

[0045] (4) Turn off the calcining furnace and let it cool to room temperature, then take out the dried paint.

[0046] Example 4

[0047] The difference from Example 1 is that the calcination temperature is 380±3°C, and the remaining steps are the same as Example 1.

[0048] Comparative Example 1

[0049] The difference from Example 1 is that the calcination temperature is 400±3°C, and the remaining steps are the same as Example 1.

[0050] Comparative Example 2

[0051] The difference from Example 1 is that the calcining furnace is not rolled during calcination, that is:

[0052] (1) Grind the dry paint raw materials and sieve through 10 mesh;

[0053] (2) Place the sieved dry paint into the calcining furnace, fasten the sealing cover, and leave a 1 cm hole in the center of the sealing cover;

[0054] (3) Start the calcining furnace for calcination at a temperature of 350±3°C for 2 h;

[0055] (4) Turn off the calcining furnace and let it cool to room temperature, then take out the dried paint.

[0056] Comparative Example 3

[0057] A method for calcining dry lacquer is as follows:

[0058] (1) Grind the dry paint raw materials and sieve through 10 mesh;

[0059] (2) Place the sieved dry paint into the calcining furnace, fasten the sealing cover, and leave a 1 cm hole in the center of the sealing cover;

[0060] (3) Start the calcining furnace and calcine at a temperature of 350±3℃. After calcining for 10 minutes, rotate the calcining furnace once. Continue calcining for 25 minutes and rotate the calcining furnace once. Then, calcine for 30 minutes and rotate the calcining furnace once until no smoke is emitted from the sealing cover hole. The whole calcining process takes 4 hours.

[0061] (4) Turn off the calcining furnace and let it cool to room temperature, then take out the dried paint.

[0062] Effect Experiment

[0063] 1. Urushiol extraction experiment

[0064] The Elsohly method was used to extract urushiols from raw lacquer and calcined lacquer. 5.0 g of raw lacquer (purchased from Nanchong Chunfan Chinese Medicine Cooperative, batch number 240123), 5.0 g of purchased calcined lacquer (purchased from Anhui Sanyuantang Chinese Medicine Co., Ltd., batch number 240401), and 5.0 g of calcined lacquer from Examples 1-4 and Comparative Examples 1-3 were accurately weighed and extracted with 100 mL of acetone for 24 h. The extract was filtered and concentrated under reduced pressure. The concentrated extract was washed with a small amount of acetone. After the acetone was evaporated, it was extracted twice with distilled water-chloroform (volume ratio of 30:60), each extraction for 5 h. After the extraction was completed, the aqueous phase was discarded, the chloroform part was collected and concentrated under reduced pressure, and the extract was washed with a small amount of n-hexane. After the n-hexane was evaporated, it was extracted twice with n-hexane-acetonitrile (volume ratio of 40:60), each extraction for 5 h. The acetonitrile part was collected and concentrated under reduced pressure, and after evaporation, it was the urushiol. Dissolve the above-mentioned urushiol in methanol and make the volume to 25 mL. Take 0.01 mL of the solution and dilute it 10 times with methanol. Filter it through a 0.45 μm organic phase filter membrane to obtain the test sample solution.

[0065] HPLC detection of urushiol: the chromatographic column is ChromCore C18 (250mm×4.6mm, 5μm); the volume flow rate is 0.5mL / min; the detection wavelength is 254nm; the column temperature is 35℃; the mobile phase is acetonitrile-water (volume ratio is 78:22); the analysis time is 50min; the injection volume is 10μL.

[0066] The results are shown in Table 1 and Figure 2 、 Figure 3 、 Figure 4 shown.

[0067] The total ash content under the dry paint item of the 2020 edition of the "Chinese Pharmacopoeia" shall not exceed 8.0%, and the acid-insoluble ash shall not exceed 5.0% (determined according to 2302 of the General Rules of Part IV of the 2020 edition of the "Chinese Pharmacopoeia"). The results are shown in Table 1.

[0068] Table 1

[0069]

[0070] 2. Stability test

[0071] The raw lacquer, the purchased calcined lacquer and the calcined lacquer prepared in Example 1 were leached with acetone for 24 hours and their color changes were observed. The results were as follows: Figure 1 shown.

[0072] Depend on Figure 1The results show that the purchased calcined lacquer has no color change after 24 hours of acetone extraction, indicating that the purchased calcined lacquer has been carbonized.

[0073] Since the peak area is proportional to the concentration of the substance in the sample, the larger the area, the higher the concentration and the higher the content. Figure 2 、 Figure 3 、 Figure 4 It can be seen that the calcined dry lacquer in Example 1-4 has a high and stable lacquer phenol content. It can be concluded from Table 1 that the dry lacquer calcined in the embodiment of the present invention has a high content of active ingredients and good stability, and the acid-insoluble ash of the calcined dry lacquer in Example 1-4 is much lower than the 2020 "Chinese Pharmacopoeia" specified in the 5.0% limit. The acid-insoluble ash of the dry lacquer prepared by raw dry lacquer, purchased calcined dry lacquer and comparative examples 1-4 is much higher than the 2020 "Chinese Pharmacopoeia" specified in the 5.0% limit. The 2020 "Chinese Pharmacopoeia" stipulates that the total ash content of calcined dry lacquer shall not exceed 8.0%, while the total ash content of the calcined dry lacquer prepared in the embodiment of the present invention does not exceed 6.0%, which is far below the specified standard. This shows that the present invention has unexpected technical effects.

[0074] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims

1. A method for calcining dry lacquer, characterized in that: The steps include: (1) crushing the dry paint raw materials and sieving; (2) Place the sieved dry paint into the calcining furnace, fasten the sealing cover, and leave a hole with an inner diameter of 1 cm in the center of the sealing cover; (3) starting the calcining furnace for calcining; (4) Shut down the calcining furnace and take out the dried paint; The calcination process described in step (3) is to roll the calcination furnace once when the calcination reaches 15-20 minutes, continue to roll the calcination furnace once when the calcination continues for 30-35 minutes, and then roll the calcination furnace once when the calcination continues for 45-50 minutes, until no smoke is emitted from the sealing cover hole.

2. The calcining method according to claim 1, characterized in that The sieving mesh number in step (1) is 10-15 meshes.

3. The calcining method according to claim 2, characterized in that: The sieving mesh number in step (1) is 10 meshes.

4. The calcining method according to claim 1, characterized in that The calcining furnace described in step (2) is a temperature-controlled, rolling and sealed calcining furnace.

5. The calcining method according to claim 1, characterized in that: The calcination time in step (3) is 1.5-2.5h.

6. The calcining method according to claim 1, characterized in that: The calcination temperature in step (3) is 350±3°C-380±3°C.

7. The calcining method according to claim 1, characterized in that: The calcination process described in step (3) is to roll the calcination furnace once after calcination for 15 minutes, continue to roll the calcination furnace once after calcination for 35 minutes, and then roll the calcination furnace once after calcination for 45 minutes until no smoke is emitted from the sealing cover hole.

8. The calcining method according to claim 1, characterized in that: The calcination temperature in step (3) is 360±3°C.

9. A dry lacquer calcined by the calcination method according to any one of claims 1 to 8.

10. The dry paint according to claim 9, characterized in that The total ash content of the dry paint is ≤6%, and the acid-insoluble ash content is ≤2%.

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