A process method for improving the quality and stability of powdery products and its application

Abstract

The present invention belongs to the field of cosmetics manufacturing, particularly relates to A61K8 / 02, and more specifically relates to a process method for improving the quality and stability of powder products and its application. The process method provided by the present invention at least includes: the preparation stage of mold preheating, filling, vibrating at the bottom of the grid, cooling, drying, freeze-drying, demolding, freezing, sublimation drying, and storage; the powder products prepared by the special process method of the present invention have uniform texture, complete product edges, low color difference, no pores, no wrinkles, and beautiful appearance, and are particularly suitable for the production and manufacturing of powder cosmetics.

Description

Technical Field

[0001] The present invention belongs to the field of cosmetics manufacturing, particularly relates to A61K8 / 02, and more specifically relates to a process method for improving the quality and stability of powder products and its application. Background Art

[0002] Powder cosmetics have been popular among beauty-loving ladies since ancient times. Common powder cosmetics include products such as eyeshadows, powder compacts, blushes, and contour powders. They can fix makeup and cover blemishes, absorb excess oil on the face, reduce facial shine, make the base makeup last longer, and also have the effect of adjusting skin tone, making the facial makeup more delicate and smooth. Generally, powder cosmetics with beautiful appearance, no obvious color difference, and uniform texture are more likely to arouse people's willingness to purchase. The preparation raw materials of powder cosmetics mostly include an oil phase, an emulsifier, a moisturizer, an aqueous solution, etc. Usually, when making powder products, long-term drying is required. However, only using long-term drying treatment easily causes some active ingredients to volatilize due to heat, and also leads to deformation or shrinkage of the powder cosmetics; another common preparation method for powder cosmetics is powder pressing, that is, pressing powder solid particles under a certain pressure. However, this processing technology will cause a certain decline in the fit of the cosmetics, and there may be makeup removal after use, resulting in a poor user experience.

[0003] The prior art CN114504510 A discloses a manufacturing method of a freeze-dried cosmetic material composition. Its mixed raw materials include an aqueous phase part containing a water-soluble gelling agent, an emulsifier, an oil phase part, and a powder part, and then it is obtained through cooling and freeze-drying steps. It has a beautiful appearance and relatively uniform texture. However, it can be seen from the product pictures that the finished product has a situation of edge peeling; the prior art CN116139023A discloses a preparation method of a powder product, mainly including raw material mixing and filling, baking, cooling, demolding, and vacuum freeze-drying. The obtained product has stable mechanical properties and qualified water content, and can play a certain moisturizing effect. However, it is difficult to ensure that powder cosmetics simultaneously have the advantages of complete edges, low color difference, no pores, and no wrinkles.

[0004] Therefore, providing a process method for improving the quality and stability of powder products, so that the obtained powder products have a beautiful appearance, uniform texture, complete edges, low color difference, no pores, and no wrinkles, has important practical significance. Summary of the Invention

[0005] In order to solve the above problems, the first aspect of the present invention provides a process method for improving the quality and stability of powder products, at least including the following steps:

[0006] S1. Preparation stage: Prepare and place the molds;

[0007] S2. Mold preheating: Place the mold in a heating device to preheat the mold.

[0008] S3. Filling: Put the material obtained from the S2 step into a quantitative filling machine for quantitative filling. According to the product weight requirement, quantitatively fill the material through the quantitative filling machine, with an accuracy of ≤ ±0.3 g.

[0009] S4. Vibration at the bottom of the grid: Put the material obtained from the S3 step into the grid and then place it at the bottom of the vibrator to vibrate at a certain frequency.

[0010] S5. Cooling: Cool the material obtained from the S4 step at a low temperature in a low-temperature environment.

[0011] S6. Microwave drying: Microwave dry the material obtained from the S5 step.

[0012] S7. Pre-freezing: Pre-freeze the material obtained from the S6 step.

[0013] S8. Demolding: Demold the material obtained from the S7 step.

[0014] S9. Freezing: Place the material obtained from the S8 step in a freeze dryer for freezing and shaping.

[0015] S10. Sublimation drying: Place the material obtained from the S9 step in a freeze dryer for stepwise sublimation drying.

[0016] S11. Baking: Bake and heat the material obtained from the S10 step.

[0017] S12. Low-temperature storage: Store the material obtained from the S11 step in a constant temperature and humidity environment.

[0018] Preferably, the temperature for mold preheating in the S2 step is 50 - 350 °C; as an implementable case, the preheating temperature of the mold can include one of 50 °C, 100 °C, 150 °C, 200 °C, 250 °C, 300 °C, or 350 °C.

[0019] During the experiment, the inventor found that preheating the mold before filling can improve the problems of large color difference and pores in the powder products. Especially when the heating temperature is limited to 55 - 85 °C, the pores in the prepared powder products can be avoided. In the process of preparing powder products, it generally goes through the filling and drying stages. Due to the subsequent drying causing the temperature to rise, the uniformity of the powder is affected, and thus the problem of pores appears. During the exploration process, the inventor checked each process step one by one and finally found that preheating the mold before filling the powder products can greatly reduce the problem of pores in the obtained products and improve the yield. The inventor speculated that the possible reasons are as follows: The process of preheating the mold can reduce the change in temperature difference, avoiding the irregular movement of internal molecules in the material due to the temperature difference phenomenon within the system, which intensifies due to the temperature difference, thereby reducing the color difference caused by the structural change of the powder product. At the same time, the reduction in temperature difference also avoids the rapid cooling of the material during the filling process, enabling the material to flow into every corner and avoiding the generation of pores. At the same time, the inventor also found that if the preheating temperature of the mold is too high, it will also cause damage to the raw material system, affecting the yield or surface color of the product.

[0020] Preferably, the filling temperature in step S3 is 50 - 100 °C; as an example of an implementable case, the filling temperature may include one of 50 °C, 60 °C, 70 °C, 80 °C, 90 °C, or 100 °C.

[0021] Preferably, the vibration frequency in step S4 is 100 - 500 Hz; as an example of an implementable case, the vibration frequency includes one of 100 Hz, 150 Hz, 200 Hz, 250 Hz, 300 Hz, 400 Hz, 450 Hz, 500 Hz.

[0022] In the present invention, a grid needs to be added during the filling of powdery products, and the bottom vibration method is adopted. However, the vibration frequency needs to be maintained at 100 - 500 Hz. During the preparation of powdery products, the traditional method generally mixes raw materials to obtain an oil-in-water / water-in-oil system, then fills it, and then bakes it after cooling. Such a process method is simpler, but the obtained products are prone to problems such as not reaching the edges or having air holes. On the premise of preheating the mold, the inventor explored and found that during filling, by bottom vibration and adding a grid, the generation of air holes can be further alleviated, and the shape of the powdery product after filling can be ensured to be regular. The applicant speculates that the reason for this phenomenon is that within this range, it can ensure that the material does not produce "accumulation" or particle stratification, improve the fluidity of the material, and achieve full filling in the mold. However, when the vibration frequency is too high, it will cause an increase in the movement frequency of the material particles, resulting in particle stratification, and the too-fast movement frequency will also increase the "floating" degree of the material, leading to a decrease in the filling effect at the edges. When the vibration frequency is lower than 100 Hz, the inventor found that its auxiliary effect on the material is insufficient, the flatness is affected, and the phenomenon of not reaching the edges appears.

[0023] Preferably, the equipment used in the S5 step includes one of a freezing tunnel, a freezing air hood, and a freezer; the low-temperature environment is -10 to 25 °C, and the cooling time is 2 - 30 min; as an implementable example, the low temperature can include one of -10 °C, -5 °C, 0 °C, 5 °C, 15 °C, or 25 °C; the cooling time can include one of 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, 12 min, 15 min, 20 min, 25 min, 30 min.

[0024] Preferably, the S6 step is microwave drying; preferably, the conditions for microwave drying are a total microwave power of 25 KW: an opening rate of 15 - 50%, a microwave frequency: 300 MHz - 300 GHz, a wavelength of 1 meter to 1 millimeter for the battery wave, a linear velocity: 0.5 - 2 m / min, and the temperature in the tunnel cavity is 25 - 65 °C.

[0025] During the experiment, the inventor found that due to the liquid-phase substances present in the raw materials, surface anomalies such as pores or wrinkles would appear in the finished powder products. The inventor optimized the preparation process and proposed a microwave drying step. The inventor found that after the microwave drying step, especially under the process parameters of a total microwave power of 25KW, an opening rate of 15 - 50%, a microwave frequency of 300MHz - 300GHz, an electromagnetic wave with a wavelength of 1 meter to 1 millimeter, a linear velocity of 0.5 - 2m / min, and a temperature of 25 - 65°C in the tunnel cavity, it is possible to reduce the water content of the raw materials while avoiding a decline in the performance of the active substances in the powder products. However, in this system, the inventor found that products without microwave drying / baking would have a soft texture and exhibit the phenomenon of powder flying during application. Through a large number of experimental explorations, the inventor found that adding an additional microwave drying / baking step before freezing would significantly improve the problem of the soft texture of the powder quality. The applicant speculates that the reason for this phenomenon is as follows: In this system, through gradual heating, the frequency of intermolecular thermal motion can be ensured to be stable, ensuring a relatively strong orderliness in the intermolecular forces and entanglement degree between the molecular chains of raw materials such as carrageenan in the system, avoiding problems such as the inability of the molecular conformation to immediately restore the equilibrium conformation adapted to the environmental conditions and the appearance of wrinkles during subsequent low-temperature (-5°C) storage. At the same time, the baking before storage reduces the internal moisture of the raw materials to 5%, avoiding the phenomenon of powder caking during use, improving the yield rate, and enhancing the satisfaction of product use.

[0026] Preferably, the pre-freezing equipment in the S7 step includes one of a liquid nitrogen tunnel, a freezing tunnel, and a freeze dryer. The pre-freezing temperature is -10 to -70°C, and the pre-freezing time is 0.1 - 2h. As an implementable case, the freeze-drying temperature can include one of -10°C, -15°C, -20°C, -35°C, -45°C, -50°C, -60°C, -70°C; the freeze-drying time includes one of 0.1h, 0.3h, 0.5h, 1h, 1.2h, 1.5h, or 2h.

[0027] Preferably, in the S10 step, the stepwise temperature increase is one step for every 5 - 15°C, each step lasting 1 - 4h, with a total duration of 12 - 24h.

[0028] Preferably, the stepwise temperature increase in the S10 step is carried out under a negative pressure condition, and the negative pressure is -1MPa to 0.4MPa; as an implementable case, the negative pressure can include -1MPa, -0.5MPa, 0.05MPa, 0.1MPa, 0.15MPa, 0.2MPa, 0.3MPa, or 0.4MPa.

[0029] As an implementable case, the time for each stage may include one of 1h, 1.5h, 2h, 2.5h, 3h, 3.5h or 4h; the uniform temperature increase for each stage includes one of 5℃, 6℃, 7℃, 8℃, 9℃, 10℃, 11℃, 12℃, 13℃, 14℃ or 15℃.

[0030] Further preferably, the temperature increases by 10℃ for each stage; each stage is 2h, and the total duration is 12h.

[0031] Preferably, the equipment for baking in S11 is a drying oven or an incubator; the baking conditions are: temperature 45 - 65℃; time is 5 - 10h. As an implementable case, the heat temperature may include one of 45℃, 50℃, 55℃ or 60℃; the time may include one of 5h, 6h, 7h, 8h, 9h or 10h.

[0032] The second aspect of the present invention provides an application of a process method for improving the quality and stability of powdery products, which is mainly applied in the preparation of powdery cosmetics.

[0033] Preferably, the raw materials for the preparation of the powdery cosmetics include an oil phase, an aqueous phase, and a powder phase; the aqueous phase includes one or more of a solution, a thickener, an emulsifier, and a preservative; the oil phase includes one or more of a humectant, an emulsifier, a thickener, a fragrance, and an active ingredient; the powder phase includes one or more of a filler, a humectant, an antioxidant, and a fragrance.

[0034] In some preferred embodiments, the powdery products include, but are not limited to, the combination of a cream powder and a powder product, a cream powder, or a powder product.

[0035] Beneficial effects

[0036] (1) The present invention provides a process method for improving the quality and stability of powdery products, and can produce powdery cosmetics with uniform texture, complete edges, low color difference, no pores, and no wrinkles, with a beautiful appearance, and is especially suitable for the production and manufacturing of powdery cosmetics.

[0037] (2) By preheating the mold at a specific temperature, the present invention can effectively reduce the color difference and avoid the generation of pores during production.

[0038] (3) The present invention adopts a combination of microwave drying and baking to improve the wrinkles and soft powder flying phenomenon on the surface of the powdery products, improve the yield rate and the quality of the products, and enhance the user satisfaction of using the powdery products.

[0039] (4) In the operation step of vibrating at the bottom of the grid in the present invention, by adjusting the vibration frequency of the vibrator to 100 - 500 Hz, it can assist the flow of the material and reduce the generation of air holes; in addition, the grid can support the material to make the material more firm and level the bottom of the material.

[0040] (5) In the preparation process of the present invention, no additional chemical additives are used, reducing the preparation cost and meeting the process requirements of green production. In addition, the powder products obtained by the present invention have strong stability and are suitable for large-scale industrial production. Description of the Drawings

[0041] Figure 1 It is a comparison diagram of the edges of the products obtained in Example 1 (right) and Comparative Example 1 (left).

[0042] Figure 2 It is a comparison diagram of the color differences of the products obtained in Example 1 (right) and Comparative Example 2 (left).

[0043] Figure 3 It is a comparison diagram of the air holes of the products obtained in Example 1 (right) and Comparative Example 3 (left).

[0044] Figure 4 It is a comparison diagram of the wrinkles of the products obtained in Example 1 (right) and Comparative Example 4 (left). Detailed Embodiments

[0045] Example 1

[0046] In the first aspect of this embodiment, a process method for improving the quality and stability of powder products is provided. The process method comprises the following steps:

[0047] S1. Preparation stage: Prepare and place the molds.

[0048] S2. Mold preheating: Load the material into the mold, place the mold in the heating equipment, and preheat the mold at 58°C.

[0049] S3. Filling: Put the material obtained in step S2 into a quantitative filling machine for quantitative filling. The filling temperature is 80°C. According to the product weight requirement, quantitatively fill the material in the quantitative filling machine with an accuracy of ≤ ±0.3 g.

[0050] S4. Vibration at the bottom of the grid: Put the material obtained in step S3 into the grid and then place it in the vibrator for vibration at 200 Hz.

[0051] S6. Microwave drying: The total microwave power is 25 KW, the opening rate is 15 - 50%, the microwave frequency is 500 MHz, the wavelength is 0.05 m for the battery wave, the linear velocity is 0.5 m / min, and the temperature in the tunnel cavity is 30°C.

[0052] S7. Pre-freezing: The material obtained in step S6 is pre-frozen at -50°C in a freezer for 5 minutes;

[0053] S8. Demolding: The material obtained in step S7 is placed in a demolding machine for demolding;

[0054] S9. Freezing: The material obtained in step S8 is freeze-dried in a freeze dryer, freeze-dried at -45°C for 0.5 hours, and shaped again;

[0055] S10. Sublimation drying: The material obtained in step S9 is placed in a temperature-rising freeze dryer for stepwise temperature-rising drying: negative pressure: -0.9 MPa, one step every 10°C, 2 hours for each step, with a total duration of 12 hours;

[0056] S11. Baking: The material obtained in step S10 is baked in a baking room at 50°C for 8 hours;

[0057] S12. Storage: The material obtained in step S11 is stored in a constant temperature and humidity environment to obtain the pre-finished powder product.

[0058] In the second aspect of this embodiment, an application of a process method for improving the quality and stability of powder products is provided, which is specifically applied to the preparation of powder cosmetics; the raw materials for the preparation of the powder cosmetics include: oil phase, water phase, and powder phase; the mass ratio of the oil phase, water phase, and powder phase is: 10:50:40; the oil phase is emulsifier Tween 60, thickener cetyl alcohol ethylhexanoate, octyldodecyl stearoyl stearate, and moisturizer squalane, and the mass ratio of Tween 60, cetyl alcohol ethylhexanoate, octyldodecyl stearoyl stearate, and squalane is 2:5:2:2; the water phase is solvent deionized water, thickener carrageenan, potassium chloride, preservative octanediol / ethylhexylglycerin, and the mass ratio of deionized water, carrageenan, potassium chloride, and octanediol / ethylhexylglycerin is 0.3:0.1:0.6:99; the powder phase is moisturizer lauroyl lysine, filler alumina, silica, boron nitride, and alloy fluorophlogopite, and the mass ratio of lauroyl lysine, alumina, silica, boron nitride, and alloy fluorophlogopite is 1:1:3:1:30.

[0059] Example 2

[0060] In the first aspect of this embodiment, a process method for improving the quality and stability of powder products is provided, and the process method is the following steps:

[0061] S1. Preparation stage: Prepare and place the molds;

[0062] S2. Mold preheating: Load the material into the mold, place the mold in a heating device, and preheat the mold at 60°C.

[0063] S3. Filling: Put the material obtained from step S2 into a quantitative filling machine for quantitative filling. The filling temperature is 75°C. According to the product weight requirement, quantitatively fill the material through the quantitative filling machine, with an accuracy of ≤±0.3 g.

[0064] S4. Vibration at the bottom of the grid: Put the material obtained from step S3 into the grid and then place it at the bottom of the vibrator for vibration at 400 Hz.

[0065] S6. Microwave drying: The total microwave power is 25 KW, the opening rate is 15 - 50%, the microwave frequency is 100 GHz, the wavelength is 0.2 m electromagnetic wave, the linear velocity is 1.0 m / min, and the temperature inside the tunnel cavity is 60°C.

[0066] S7. Pre-freezing: Pre-freeze the material obtained from step S6 in a freezer at -70°C for 3 min.

[0067] S8. Demolding: Place the material obtained from step S7 in a demolding machine for demolding.

[0068] S9. Freezing: Place the material obtained from step S8 in a freeze dryer for freeze-drying, freeze-dry at -45°C for 0.5 h, and shape it again.

[0069] S10. Sublimation drying: Place the material obtained from step S9 in a temperature-rising freeze dryer for stepwise temperature-rising drying: negative pressure: -0.4 MPa, one step every 10°C, 2 h for each step, and the total duration is 12 h.

[0070] S11. Baking: Bake the material obtained from step S10 in a baking room at 50°C for 8 h.

[0071] S12. Storage: Store the material obtained from step S11 in a constant temperature and humidity environment to obtain the pre-finished powder product.

[0072] In the second aspect of this embodiment, a process method for improving the quality and stability of powdery products is provided, which is specifically applied to the preparation of powdery cosmetics; the raw materials for the preparation of the powdery cosmetics include: an oil phase, an aqueous phase, and a powder phase; the mass ratio of the oil phase, the aqueous phase, and the powder phase is: 10:50:40; the oil phase is emulsifier Tween 60, thickener cetyl alcohol ethylhexanoate, octyldodecyl stearoyl stearate, and moisturizer squalane, and the mass ratio of Tween 60, cetyl alcohol ethylhexanoate, octyldodecyl stearoyl stearate, and squalane is 2:5:2:2; the aqueous phase is solvent deionized water, thickener carrageenan, potassium chloride, preservative octylene glycol / ethylhexylglycerin, and the mass ratio of deionized water, carrageenan, potassium chloride, and octylene glycol / ethylhexylglycerin is 0.3:0.1:0.6:99; the powder phase is moisturizer lauroyl lysine, filler alumina, silica, boron nitride, and alloy fluorophlogopite, and the mass ratio of lauroyl lysine, alumina, silica, boron nitride, and alloy fluorophlogopite is 1:1:3:1:30.

[0073] Example 3

[0074] In the first aspect of this embodiment, a process method for improving the quality and stability of powdery products is provided. The process method comprises the following steps:

[0075] S1. Preparation stage: Prepare and place the molds.

[0076] S2. Mold preheating: Load the material into the molds, place the molds in a heating device, and preheat the molds at 70 °C.

[0077] S3. Filling: Put the material obtained through the S2 step into a quantitative filling machine for quantitative filling. The filling temperature is 90 °C. According to the product weight requirement, quantitatively fill the material through the quantitative filling machine, and the accuracy is ≤ ±0.3 g.

[0078] S4. Placing into the grid and bottom vibration: Put the material obtained through the S3 step into the grid and then place it in a vibrator for vibration at 500 Hz.

[0079] S6. Microwave drying: The total microwave power is 25 KW, the opening rate is 15 - 50%, the microwave frequency is 1000 MHz, the wavelength is 0.03 m for the battery wave, the linear velocity is 2.0 m / min, and the temperature in the tunnel cavity is 38 °C.

[0080] S7. Pre-freezing: Pre-freeze the material obtained through the S6 step in a freezer at -60 °C for 3 min.

[0081] S8. Demolding: Place the material obtained through the S7 step in a demolding machine for demolding.

[0082] S9. Freezing: Place the material processed in step S8 in a freeze dryer for freeze-drying. Freeze-dry at -45°C for 0.5 h and shape it again.

[0083] S10. Sublimation drying: Place the material obtained from step S9 in a temperature-rising freeze dryer for stepwise temperature-rising drying: Negative pressure: -0.8 MPa, with a 10°C step for each stage, 2 h for each stage, and a total duration of 12 h.

[0084] S11. Baking: Bake the material obtained from step S10 in a baking room at 50°C for 8 h.

[0085] S12. Storage: Store the material obtained from step S11 in a constant temperature and humidity environment to obtain the pre-finished powder product.

[0086] In the second aspect of this embodiment, a process method for improving the quality and stability of powder products is provided, which is specifically applied to the preparation of powder cosmetics; the raw materials for the preparation of the powder cosmetics include: oil phase, water phase, and powder phase; the mass ratio of the oil phase, water phase, and powder phase is: 10:50:40; the oil phase is emulsifier Tween 60, thickener cetyl alcohol ethylhexanoate, octyldodecyl stearoyl stearate, and moisturizer squalane, and the mass ratio of Tween 60, cetyl alcohol ethylhexanoate, octyldodecyl stearoyl stearate, and squalane is 2:5:2:2; the water phase is solvent deionized water, thickener carrageenan, potassium chloride, preservative octanediol / ethylhexylglycerin, and the mass ratio of deionized water, carrageenan, potassium chloride, and octanediol / ethylhexylglycerin is 0.3:0.1:0.6:99; the powder phase is moisturizer lauroyl lysine, filler alumina, silica, boron nitride, and alloy fluorophlogopite, and the mass ratio of lauroyl lysine, alumina, silica, boron nitride, and alloy fluorophlogopite is 1:1:3:1:30.

[0087] Comparative Example 1

[0088] The specific implementation manner of this solution is the same as that of Example 1. Different from Example 1, the vibration frequency in step S4 is 800 Hz, and the obtained powder product is shown in Figure 1 .

[0089] The edge comparison diagram of the products obtained in Example 1 (right) and Comparative Example 1 (left) is shown in Figure 1 as follows.

[0090] Comparative Example 2

[0091] The specific implementation manner of this solution is the same as that of Example 1. Different from Example 1, the preheating temperature of the mold in step S2 is 100°C, and the obtained powder product is shown in Figure 2 .

[0092] The color difference comparison diagram of the products obtained in Example 1 (right) and Comparative Example 2 (left) is as Figure 2 shown.

[0093] Comparative Example 3

[0094] The specific implementation manner of this solution is the same as that of Example 1. The difference from Example 1 is that there is no step S2, and the prepared powder product is shown in Figure 3 .

[0095] The pore comparison diagram of the products obtained in Example 1 (right) and Comparative Example 3 (left) is as Figure 3 shown.

[0096] Comparative Example 4

[0097] The specific implementation manner of this solution is the same as that of Example 1. The difference from Example 1 is that there is no step S11, and the prepared powder product is shown in Figure 4 .

[0098] The wrinkle comparison diagram of the products obtained in Example 1 (right) and Comparative Example 4 (left) is as Figure 4 shown.

[0099] Performance evaluation

[0100] Test object: The processes of Examples 1 to 3 and Comparative Examples 1 to 4 are used in the formula of the powder product provided in Example 1, and the obtained powder products are analyzed and compared;

[0101] Test method: Visually observe whether there are edge defects, color differences, pores and wrinkles on the surface of the corresponding powder product finished product, and record the test results in Table 1.

[0102] Table 1

[0103]

[0104]

Claims

1. A process method for improving the quality and stability of powdery products, characterized in that, The described process method at least includes the following steps: S1. Preparation stage: Prepare and place the molds. S2. Mold preheating: Load the material into the mold, place the mold in a heating device, and preheat the mold. The preheating temperature is 58 - 70°C. S3. Filling: Put the material obtained from step S2 into a quantitative filling machine for quantitative filling. According to the product weight requirement, quantitatively fill the material through the quantitative filling machine, with an accuracy of ≤ ±0.3 g. S4. Vibration at the bottom of the grid: Put the material obtained from step S3 into the grid and then place it in a vibrator to vibrate at a frequency of 200 - 500 Hz. S5. Cooling: Cool the material obtained from step S4 at a low temperature in a low-temperature environment. S6. Microwave drying: Microwave dry the material obtained in step S5. The conditions for microwave drying are: total microwave power 25 KW, opening rate 15 - 50%; microwave frequency 500 MHz - 100 GHz. S7. Pre-freezing: Pre-freeze the material obtained from step S6 at -70°C to -50°C. S8. Demolding: Demold the material obtained from step S7. S9. Freezing: Place the material obtained from step S8 in a freeze dryer for freezing and shaping. S10. Sublimation drying: Place the material obtained from step S9 in a freeze dryer for stepwise sublimation drying. S11. Baking: Bake and heat the material obtained from step S10. The conditions for baking are: temperature 45 - 65°C; time 5 - 10 h. S12. Storage: Store the material obtained from step S11 in a constant temperature and humidity environment to obtain the product.

2. The process method for improving the quality and stability of powdery products according to claim 1, characterized in that: The equipment used in step S5 includes one of a freezing tunnel, a freezing air hood, and a freezer.

3. The process method for improving the quality and stability of powdery products according to claim 1, characterized in that: The operating conditions of step S5 are: the low-temperature environment is -10 to 25°C, and the cooling time is 2 - 30 min.

4. The process method for improving the quality and stability of powdery products according to claim 1, characterized in that: In the microwave drying carried out in step S6, the wavelength of the electromagnetic wave is 1 mm to 1 m, the linear velocity is 0.5 - 2 m / min, and the temperature in the microwave tunnel cavity is 25 - 65°C.

5. The process method for improving the quality and stability of powdery products according to claim 1, characterized in that: In step S7, the pre-freezing equipment includes one of a liquid nitrogen tunnel, a freezing tunnel, and a freeze dryer, and the pre-freezing time is 0.1 - 2 h.

6. The process method for improving the quality and stability of powdery products according to claim 1, characterized in that: In the stepwise sublimation drying of step S10, stepwise temperature increase is carried out, with each step being 5 - 15°C, each step lasting 1 - 4 h, and the total duration being 12 - 24 h.

7. Use of a process method for improving the quality and stability of powdery products according to any one of claims 1-6, characterized in that, It is applied to the preparation of powdery cosmetics.

8. Use of the process method for improving the quality and stability of powdery products according to claim 7, characterized in that, The raw materials for the preparation of the described powdery cosmetics include an oil phase, a water phase, and a powder phase; the water phase includes one or more of a solution, a thickener, an emulsifier, and a preservative; the oil phase includes one or more of a humectant, an emulsifier, a thickener, a fragrance, and an active ingredient; the powder phase includes one or more of a filler, a humectant, an antioxidant, and a fragrance.

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