Preparation method of bulk powder cosmetics and bulk powder cosmetics

Abstract

The present application provides a method for preparing block powder cosmetics and block powder cosmetics. The method for preparing block powder cosmetics includes the following steps: mixing: providing raw materials for preparing block powder cosmetics, mixing the raw materials to obtain a material body; filling and pre-curing: filling the material body into a mold according to a preset amount through an air pressure feeding device, extruding and drying the material body to obtain a powder masterbatch pre-cured in the mold; freezing: freezing the pre-cured powder masterbatch at a low temperature; demolding and drying: separating the frozen powder masterbatch from the mold, drying it, and obtaining a block powder cosmetic; or drying the frozen powder masterbatch, separating it from the mold, and obtaining a block powder cosmetic. The preparation method of the present application can improve the problems of shrinkage deformation during the preparation process, as well as poor drop resistance, cracking, pores, and softness of the finished product, and will not cause inactivation of high-temperature sensitive active substances during the preparation process.

Description

Technical Field

[0001] The present application belongs to the technical field of cosmetics, and in particular relates to a preparation method of block powder cosmetics and block powder cosmetics. Background Art

[0002] The preparation of bulk powder cosmetics typically includes steps such as mixing, filling, demolding, and solvent removal. During the filling process, to achieve good filling efficiency and effectiveness, the composition must possess good fluidity. Therefore, the composition to be filled must contain a certain amount of solvent (usually water, or a mixture of water and one or more organic solvents, with the solvent addition generally exceeding 50%), and the composition to be filled must be preheated at a high temperature (usually 70-90°C). Because bulk powder cosmetics contain a high content of powder particles and the extent to which the material's fluidity can be improved is limited, even with the addition of solvent and heated filling, air holes are still very likely to form in the sharp angles of some fine reliefs.

[0003] After the filling step, a solvent removal step is required. For example, this involves heating, baking, freeze-drying, and other process steps to remove the solvent from the powdered cosmetic. The solvent content in the final powdered cosmetic is generally controlled to below 5%. However, this solvent removal process is difficult to control and can cause shrinkage and deformation during the production process, resulting in poor drop resistance, cracking, porosity, and softness in the finished product.

[0004] In addition, adding functional ingredients to cosmetic powder products is the product demand trend. The heating operation in the filling step can easily lead to the inactivation of functional ingredients, resulting in some active substances that are sensitive to high temperatures being unable to be used in cosmetic powder products. Summary of the Invention

[0005] The embodiments of the present application provide a method for preparing block powder cosmetics and block powder cosmetics to improve shrinkage and deformation during the preparation process, as well as poor drop resistance, cracking, pores, and softness of the finished product, and will not cause inactivation of high-temperature sensitive active substances during the preparation process.

[0006] In the first aspect, an embodiment of the present application provides a method for preparing block powder cosmetics, comprising the following steps: mixing: providing raw materials for preparing block powder cosmetics, mixing the raw materials to obtain a material body; filling and pre-curing: filling the material body into a mold according to a preset amount through an air pressure feeding device, extruding and drying the material body to obtain a powder master product pre-cured and formed in the mold; freezing: freezing the pre-cured powder master product at a low temperature; demolding and drying: separating the frozen powder master product from the mold, drying it, and obtaining a block powder cosmetic; or drying the frozen powder master product, separating it from the mold, and obtaining a block powder cosmetic.

[0007] According to an embodiment of the first aspect of the present application, the step of filling the material into the mold according to a preset amount via the air pressure feeding device includes: pressing or sucking the material into the mold by the action of air pressure.

[0008] According to an embodiment of the first aspect of the present application, the viscosity of the material is below 30,000 cP, preferably 10,000 cP to 25,000 cP; the pressure in the pneumatic feeding device is: 0.02 to 0.1 MPa, preferably 0.04 to 0.08 MPa.

[0009] According to an embodiment of the first aspect of the present application, the extrusion drying includes performing filter pressing on the material body in the mold to allow at least part of the solvent to dialyze out of the material body, and transferring the dialyzed solvent simultaneously with or after the filter pressing.

[0010] According to an embodiment of the first aspect of the present application, the extrusion drying includes performing filter pressing and negative pressure suction on the material in the mold; the pressure parameter of the filter pressing is: 0.05-3 MPa, preferably 0.2-1.5 MPa. The pressure parameter of the negative pressure suction is: 0.02-0.1 MPa, preferably 0.05-0.08 MPa.

[0011] According to an embodiment of the first aspect of the present application, in the step of simultaneously performing filter pressing and negative pressure suction on the material body in the mold, the solvent content in the material body is reduced to 30~80% of the original solvent content in the material body before filter pressing and negative pressure suction, preferably 30~50%, to obtain a powder masterbatch pre-cured in the mold.

[0012] According to the embodiment of the first aspect of the present application, the solvent content in the prepared block powder cosmetics is less than 5%, preferably within 1%.

[0013] According to an embodiment of the first aspect of the present application, the step of freezing the pre-cured powder masterbatch at low temperature is performed in a liquid nitrogen quick-freezing device.

[0014] According to an embodiment of the first aspect of the present application, the liquid nitrogen quick-freezing device is a liquid nitrogen tunnel, and the temperature inside the liquid nitrogen tunnel is -120~-70°C, preferably -95~-80°C; the powdered mother product passes through the liquid nitrogen tunnel on a conveyor belt in the liquid nitrogen tunnel at a speed of 0.4~1.2 m / min, preferably 0.6~1 m / min, and the powdered mother product passes through the liquid nitrogen tunnel for 5~15 minutes, preferably 6~10 minutes.

[0015] According to an embodiment of the first aspect of the present application, drying includes one or any combination of heating drying, vacuum drying, freeze drying, microwave drying and supercritical fluid drying.

[0016] According to an embodiment of the first aspect of the present application, drying includes freeze drying and a combination of one or more of the following drying methods: heating drying, vacuum drying, microwave drying or supercritical fluid drying.

[0017] According to an embodiment of the first aspect of the present application, the temperature of the drying step is lower than 40°C.

[0018] According to the embodiment of the first aspect of the present application, the raw materials for preparing block powder cosmetics include powder phase components, oil phase components and water phase components; the powder phase components include: one or more of fillers and colorants; the oil phase components include: one or more of emollients, antioxidants, and sunscreens; the water phase components include: one or more of solvents, thickeners, film formers, emollients, emulsifiers, preservatives, and active ingredients.

[0019] According to an embodiment of the first aspect of the present application, the thickener and film-forming agent are selected from natural water-soluble polymers or derivatives thereof, synthetic water-based polymers or water-based inorganic thickeners; the natural water-soluble polymers or derivatives thereof are selected from at least one of alginic acid, agar, carrageenan, xanthan gum, gellan gum, crisp chondrus crispus, xanthan gum, guar gum, tamarind gum, tara gum, gum arabic, tragacanth gum, tara gum, pectin, arabogalactan, wheat protein, soy protein, gelatin, casein, chitosan, curdlan, cyclodextrin, hyaluronic acid, konjac gum, tremella polysaccharide, codyl gum, microcrystalline cellulose, methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, starch phosphate, starch, sodium hydroxymethyl starch, sodium polyacrylate grafted starch, and hydroxypropyl guar gum;

[0020] The synthetic water-based polymer is selected from at least one of acrylates / C10-30 alkyl acrylate crosspolymer, carbomer, acrylates / octylacrylamide copolymer, acrylates / ethylhexyl acrylate copolymer, sodium acrylate / sodium acryloyldimethyl taurate copolymer, acrylates / octylacrylamide copolymer, styrene / acrylates copolymer, acrylates copolymer, hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer, polyacrylate crosspolymer-6, acrylates / stearyl ether-20 methacrylate copolymer, ammonium acryloyldimethyl taurate / beheneth-25 methacrylate crosspolymer, ammonium acrylates copolymer, sodium polyacrylate, sodium polyacryloyldimethyl taurate, polyacrylamide, polyvinyl pyrrolidone, polyvinyl alcohol, VP / VA copolymer, polyurethane-1, and polyurethane-35;

[0021] The aqueous inorganic thickener is selected from at least one of magnesium aluminum silicate, sodium magnesium lithium silicate, lithium magnesium silicate, sodium magnesium silicate, montmorillonite or their derivatives;

[0022] Based on the prepared bulk powder cosmetics, the mass percentage of the aqueous inorganic thickener and / or film-forming agent is 0.02-15%, preferably 0.05-5%.

[0023] According to an embodiment of the first aspect of the present application, the emollient is selected from at least one of alcohols, silicone oil, mineral oil, synthetic oil, animal and plant oils, or derivatives thereof;

[0024] The animal or plant oil or its derivative is selected from at least one of glycerin, propylene glycol, dipropylene glycol, pentylene glycol, butylene glycol, ethylene glycol, hexylene glycol, sorbitol, xylitol, polyethylene glycol, dimethicone, caprylyl methicone, phenyl trimethicone, cetyl dimethicone, C30-45 alkyldimethylsilyl polypropyl silsesquioxane, bis-PEG-18 methyl ether dimethyl silane, white mineral oil, petrolatum, hydrogenated polyisobutene, lanolin and its derivatives, octyldodecanol, caprylic / capric triglyceride, ethylhexyl palmitate, bis-diglyceryl polyacyladipate-2, isononyl isononanoate, jojoba seed oil, coconut oil, hydrogenated coconut glycerides, meadowfoam seed oil, olive oil, squalane C9-12 alkane, coconut oil caprylate / caprate, tocopheryl acetate, and methyl gluceth-10;

[0025] Based on the prepared block powder cosmetics, the mass percentage of the emollient and moisturizing agent is 0.1-40%, preferably 0.5-30%.

[0026] According to an embodiment of the first aspect of the present application, the filler is selected from at least one of mica, talc, synthetic fluorphlogopite, kaolin, bentonite, boron nitride, bismuth oxychloride, silica, sodium potassium aluminum silicate, lauroyl lysine, magnesium stearate, magnesium myristate, calcium aluminum borosilicate, tin oxide, calcium sodium borosilicate, aluminum hydroxide, zinc stearate starch and its derivatives, and plastic microbeads;

[0027] The colorant is selected from at least one of iron oxides (CI 77499, CI 77491, CI 77492), titanium dioxide (CI 77891), iron blue (CI 77510), ultramarine (CI 77007), manganese violet (CI 77742), chromium oxide green (CI 77288), chromium hydroxide green, carmine (CI 75470), carbon black (CI 77266), CI 15850, CI 19140, CI 45410, CI 16035, CI 45380, CI 17200, CI 73360, CI 42090, and CI 47005;

[0028] Based on the prepared bulk powder cosmetics, the total mass percentage of the filler and the colorant is 50-99%, preferably 70-95%.

[0029] According to an embodiment of the first aspect of the present application, the preservative is selected from at least one of phenoxyethanol, parabens, chlorphenesin, potassium sorbate, sodium benzoate or a preservative synergist;

[0030] The preservative synergist is selected from at least one of caprylyl glycol, p-hydroxyacetophenone, ethylhexylglycerin, 1,2-hexanediol, caprylhydroxamic acid, 1,2-pentanediol, glyceryl caprylate, and cymene.

[0031] According to an embodiment of the first aspect of the present application, the active substance is selected from a high temperature sensitive active substance or a high temperature insensitive active substance.

[0032] According to an embodiment of the first aspect of the present application, the active substance is selected from high-temperature sensitive active substances, and the high-temperature sensitive active substance is selected from at least one of polypeptide active substances, astaxanthin, vitamin A alcohol or its derivatives, vitamin C or its derivatives, and arbutin.

[0033] According to an embodiment of the first aspect of the present application, the solvent is water or a mixture of water and an organic solvent.

[0034] According to an embodiment of the first aspect of the present application, the thickener is an inorganic thickener; preferably, the inorganic thickener is at least one of magnesium aluminum silicate, lithium magnesium sodium silicate, lithium magnesium silicate, sodium magnesium silicate, montmorillonite or its derivatives.

[0035] In a second aspect, an embodiment of the present application provides a block-shaped powder cosmetic, which is prepared by the method of an embodiment of the first aspect of the present application.

[0036] According to an embodiment of the second aspect of the present application, the block-shaped powder cosmetics are selected from pressed powder, blush, eye shadow or highlighter powder.

[0037] Compared with the prior art, the embodiments of the present application have at least the following beneficial effects:

[0038] First, bulk powder cosmetics are nearly solvent-free, but solvents are necessary during the preparation process for raw material mixing and transportation. The addition and removal of solvents not only affects production energy efficiency but also has an adverse effect on the performance of the final product. In this application, the material is quantitatively filled into the mold via a pneumatic feeding device, which reduces the requirements for material fluidity and eliminates the need to add excessive solvent. In addition, extrusion drying is implemented during the filling step, which significantly reduces the solvent content in the material and shortens the subsequent drying time from 12 to 24 hours to 6 to 10 hours, improving production efficiency and effectively reducing the problems of shrinkage deformation, cracking, and poor drop resistance in the final product.

[0039] Second, for block powder cosmetics that form fine reliefs, the material is quantitatively filled into the mold through an air pressure feeding device, and the material in the mold is simultaneously filtered and vacuum-sucked. The pressure assists the material to be filled into the sharp corners of the fine relief. Even if the viscosity of the material is high, it can still be well filled into the sharp corners of the fine relief and achieve a good density, solving the problems of pores and softness in the finished product.

[0040] Third, for block powder cosmetics with added active ingredients, the preparation process of this application does not include any high-temperature process, the filling step can be performed at low temperature or room temperature, and high-temperature sensitive active ingredients can be added to the material.

[0041] In summary, the present application provides a method for preparing block powder cosmetics, which can effectively avoid shrinkage and deformation during the desolvation process of the product, as well as cracking, poor drop resistance, pores, and softness of the finished product. It can present an excellent fine relief surface and can add high-temperature sensitive active substances, while improving production efficiency and reducing energy consumption. DETAILED DESCRIPTION

[0042] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present application by illustrating the examples of the present application.

[0043] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0044] In the prior art, in the preparation of bulk powder cosmetics, the fluidity of the material is improved by adding a sufficient amount of solvent and heating the material to meet the filling and transfer requirements. After the filling step, a desolvation step is also performed, for example, by heating, baking, freeze drying and other process steps to remove the solvent from the bulk powder cosmetics. The solvent content in the final bulk powder cosmetics product generally needs to be controlled below 5%. The inventors of the present application have noticed that the desolvation process is difficult to control, which may cause the product to shrink and deform during the desolvation process, and increase the occurrence of problems such as cracking, poor drop resistance, pores, and softness in the finished product. In addition, due to the high content of powder particles in the bulk powder cosmetics raw materials and the limited improvement in the fluidity of the material, even if a solvent is added and heated for filling, pores are still very likely to appear in the sharp angles of some fine reliefs, and the heating and filling operation will also cause the high-temperature sensitive active substances added to the product to be inactivated or partially inactivated.

[0045] In order to solve the above problems, the inventors of the present application provide a block powder cosmetic and a preparation method thereof.

[0046] In the first aspect, an embodiment of the present application provides a method for preparing block powder cosmetics, comprising the following steps: mixing: providing raw materials for preparing block powder cosmetics, mixing the raw materials to obtain a material body; filling and pre-curing: filling the material body into a mold according to a preset amount through an air pressure feeding device, extruding and drying the material body to obtain a powder masterbatch pre-cured in the mold; freezing: freezing the pre-cured powder masterbatch at low temperature; demolding and drying: separating the frozen powder masterbatch from the mold, drying it, and obtaining a block powder cosmetic; or drying the frozen powder masterbatch, separating it from the mold, and obtaining a block powder cosmetic.

[0047] In the mixing step, the raw materials for preparing the bulk powder cosmetics can be purchased commercially or homemade. It is understood that the raw materials for preparing the bulk powder cosmetics generally include a powder phase component, an oil phase component, and an aqueous phase component. The raw materials can be mixed in steps using various methods commonly used in the prior art, such as mechanical stirring, and homogenization and defoaming operations can be added during the mixing process. Different mixing methods and steps can be used depending on the raw materials, and the present application is not limited thereto.

[0048] During the filling step, the preset amount can be set based on the volume of the bulk powder cosmetic, the mold capacity, or the filling requirements. The preset amount for each filling can be the same or different. In this application, a pneumatic feeding device refers to a device that fills the material into the mold by pneumatic conveying. For example, the pneumatic feeding device may include an air pump and a pipeline connected to the air pump, wherein the air pump is used to provide the air pressure required for conveying, and the pipeline is used to fill the material into the mold. This application is not limited thereto.

[0049] After the filling step, the material body is subjected to an extrusion drying operation, and a mechanical physical drying method is adopted to remove part of the solvent in the material body, so that a powder masterbatch pre-cured and formed in the mold is obtained before entering the subsequent freezing, demoulding and drying steps.

[0050] The pre-cured powder masterbatch still contains solvent. In the embodiment of the present application, after filling and pre-curing, the powder masterbatch is frozen through a freezing step, and the liquid (such as water, emulsion, etc.) in the powder masterbatch is frozen into ice.

[0051] The order of demoulding and drying steps can be adjusted. For example, the frozen powdered masterbatch is separated from the mold and then dried to obtain a block-shaped powdered cosmetic; or the frozen powdered masterbatch is dried and then separated from the mold to obtain a block-shaped powdered cosmetic.

[0052] Block powder cosmetics are close to solvent-free, but in the prior art, it is necessary to introduce solvents during the preparation process for the purpose of mixing and transporting raw materials. The addition of solvents and the drying and solvent removal process not only affect the production energy efficiency, but also have an adverse effect on the performance of the final product. In the preparation method of block powder cosmetics provided in the embodiment of the present application, the material body is quantitatively filled into the mold via an air pressure feeding device, which reduces the requirements for the fluidity of the material body and reduces the amount of solvent added; and extrusion drying is implemented in the filling step. Before entering the drying step, the solvent content in the pre-cured material body has been significantly reduced, reducing the amount of solvent removed in the subsequent drying step and shortening the drying time, thereby effectively reducing the problems of shrinkage deformation, cracking, and poor drop resistance in the final product. In some embodiments, the subsequent drying time is shortened from 12 to 24 hours to 6 to 10 hours.

[0053] For blocky powder cosmetics that form fine reliefs, the material is filled into the mold according to a preset amount through an air pressure feeding device, and during the process of squeezing and drying the material in the mold, pressure assists the material to fill into the sharp corners of the fine relief. Even if the viscosity of the material is high, it can still be well filled into the sharp corners of the fine relief and achieve a good density, thus solving the problems of pores and softness in the finished product.

[0054] For bulk powder cosmetics with added active ingredients, the preparation process of this application does not include any high-temperature processes. The filling step can be performed at low temperature or room temperature. High-temperature sensitive active ingredients can be added to the material without worrying about the active ingredients becoming ineffective due to high temperature.

[0055] Therefore, the preparation method provided in the embodiment of the present application can effectively avoid shrinkage deformation during the desolvation process of the product, as well as cracking, poor drop resistance, air holes, softness and other problems in the finished product, and can add high-temperature sensitive active substances while improving production efficiency.

[0056] In some embodiments, the step of filling the material into the mold according to a preset amount via the air pressure feeding device includes: pressing or sucking the material into the mold by the action of air pressure.

[0057] The present application does not limit the specific method of filling the material into the mold according to the preset amount. The material can be pressed into the mold by the action of air pressure. For example, the air pressure feeding device includes a feed pipe, an air pump and a discharge pipe. The air pump provides conveying air pressure to suck the material from the feed pipe into the air pressure feeding device and then press it into the mold through the discharge pipe. The material can also be sucked into the mold by the action of air pressure. For example, the air pressure feeding device is connected to the mold, and the air pressure feeding device provides conveying air pressure to suck the material into the mold.

[0058] Whether the material is pressed into or sucked into the mold, the fluidity of the material is required to be low, and there is no need to add too much solvent, which greatly shortens the subsequent drying time.

[0059] In some embodiments, the viscosity of the material is below 30,000 cP, preferably 10,000 cP to 25,000 cP; the pressure in the air pressure feeding device is 0.02 to 0.1 MPa, preferably 0.04 to 0.08 MPa.

[0060] In some embodiments, extrusion drying includes subjecting the material in the mold to pressure filtration to allow at least a portion of the solvent to be dialyzed from the material, and transferring the dialyzed solvent simultaneously with or after the pressure filtration. It is understood that transferring the dialyzed solvent can be achieved by various specific methods, including but not limited to: suction, aspiration, drainage, etc.

[0061] In some embodiments, the extrusion drying operation includes applying filter press and negative pressure suction to the material in the mold; the pressure parameter of the filter press is: 0.05-3 MPa, preferably: 0.2-1.5 MPa. The pressure parameter of the negative pressure suction is: 0.02-0.1 MPa, preferably: 0.05-0.08 MPa.

[0062] The term "filter press" in this application refers to an operation in which a certain pressure is applied to a material in the presence of a filter medium, so that at least a portion of the solvent is dialyzed out of the material through the filter medium.

[0063] The term "negative pressure suction" in this application refers to the operation of sucking and transferring the dialyzed solvent through a negative pressure difference by utilizing the principle of negative pressure vacuum suction.

[0064] Illustratively, the device for achieving pressure filtration may be a filter press, and the device for achieving negative pressure suction may be a vacuum suction pump. This application does not limit the specific composition and structure of the device.

[0065] During the operation of air pressure feeding and extrusion drying, the viscosity of the material is closely related to characteristics such as fluidity and surface tension. In the prior art, the viscosity of the filling material is generally less than 5000cP due to fluidity requirements. Since the present application adopts air pressure feeding and extrusion drying, the viscosity of the material only needs to be less than 30000cP, and the preferred viscosity range is 10000cP~25000cP. Corresponding to the viscosity range of the material, the pressure in the feeding and extrusion drying process implemented by the present invention needs to reach a certain threshold to meet the requirements of assisting the material to fill the sharp corners of the fine relief of the powder, and to achieve a good density, and to solve the problems of pores and looseness in the finished product. At the same time, the pressure in the feeding and extrusion drying process is not necessarily the higher the better. Excessive pressure is not conducive to the stability of the material and may even cause boiling of some components in the material, which in turn affects the filling effect of the material into the mold. The present application proposes that when the pressure in the pneumatic feeding device, the pressure parameters of the filter press, and the pressure parameters of the negative pressure suction are within a certain range, the material body and the pressure parameters in the pneumatic feeding and pressurized drying process meet the optimal adaptation, so that the performance of the present application in improving the porosity, softness, shrinkage deformation and drop resistance of the final product can be optimized.

[0066] Illustratively, the viscosity of the material can be 10000 cP, 11000 cP, 12000 cP, 13000 cP, 14000 cP, 15000 cP, 16000 cP, 17000 cP, 18000 cP, 19000 cP, 20000 cP, 21000 cP, 22000 cP, 23000 cP, 24000 cP, 25000 cP, 26000 cP, 27000 cP, 28000 cP, 29000 cP, 30000 cP or a range consisting of any two of the above values.

[0067] Illustratively, the pressure in the pneumatic feeding device can be 0.02 MPa, 0.03 MPa, 0.04 MPa, 0.05 MPa, 0.06 MPa, 0.07 MPa, 0.08 MPa, 0.09 MPa, 0.1 MPa, or a range consisting of any two of the foregoing values.

[0068] Illustratively, the pressure of the filter press can be: 0.05 MPa, 0.1 MPa, 0.2 MPa, 0.3 MPa, 0.4 MPa, 0.5 MPa, 0.6 MPa, 0.7 MPa, 0.8 MPa, 0.9 MPa, 1.0 MPa, 1.1 MPa, 1.2 MPa, 1.3 MPa, 1.4 MPa, 1.5 MPa, 1.6 MPa, 1.7 MPa, 1.8 MPa, 1.9 MPa, 2.0 MPa, 2.1 MPa, 2.2 MPa, 2.3 MPa, 2.4 MPa, 2.5 MPa, 2.6 MPa, 2.7 MPa, 2.8 MPa, 2.9 MPa, 3.0 MPa or a range consisting of any two of the above values.

[0069] Illustratively, the pressure parameter of negative pressure suction is: 0.02 MPa, 0.03 MPa, 0.04 MPa, 0.05 MPa, 0.06 MPa, 0.07 MPa, 0.08 MPa, 0.09 MPa, 0.1 MPa or a range consisting of any two of the above values.

[0070] In some embodiments, the material body in the mold is simultaneously subjected to the steps of filter pressing and negative pressure suction, and the solvent content in the material body is reduced to 30-80%, preferably 30-50%, of the original solvent content in the material body before filter pressing and negative pressure suction, to obtain a powder masterbatch pre-cured in the mold.

[0071] In some embodiments, the solvent content in the prepared bulk powder cosmetics is less than 5%, preferably within 1%.

[0072] In some embodiments, the step of solidifying the powdered product at low temperature is performed in a liquid nitrogen quick-freezing device. For example, the liquid nitrogen quick-freezing device can be a liquid nitrogen tunnel, a liquid nitrogen freezer, an ultra-low temperature refrigerator, etc. These devices are commercially available, and the present application is not limited thereto.

[0073] After the filling step is completed, the present invention obtains a pre-cured powdered product in a mold. This powdered product is then cryogenically solidified using a liquid nitrogen quick-freezing device. The raw material components in the powdered product undergo molecular rapid freezing in the extremely low-temperature environment. Cosmetic materials, which contain components such as oils and emulsions, experience a maximum ice crystal formation zone during the freezing process, approximately between -10°C and 0°C, where approximately 80% of the liquid (water, emulsion, etc.) turns to ice. Unlike conventional freezing methods performed before demolding in the prior art, the molecular rapid freezing process performed in a liquid nitrogen tunnel in the present invention allows the powdered product to rapidly pass through the maximum ice crystal formation zone. This results in a more even and dense distribution of ice crystals within the powdered product, resulting in a softer, more manageable freeze-dried product with smaller and more controlled dimensional variations, a more stable structure, and improved drop resistance.

[0074] Furthermore, this application also proposes the optimal liquid nitrogen quick-freezing condition parameters for the preparation of block powder cosmetics suitable for this application through research on the freezing curve of powder cosmetic materials and the energy transfer characteristics in the liquid nitrogen quick-freezing device. By completing the liquid nitrogen quick-freezing of the powder masterbatch under the above-mentioned condition parameters, the final prepared block powder cosmetics can have a uniform and dense texture, the best skin feel, and the stability of the product structure and the anti-drop ability are optimized.

[0075] In some embodiments, the liquid nitrogen quick-freezing device is a liquid nitrogen tunnel, and the temperature inside the liquid nitrogen tunnel is -120 to -70°C, preferably -95 to -80°C. A liquid nitrogen tunnel, also known as a liquid nitrogen tunnel quick-freezer, uses liquid nitrogen as a cold source and employs a continuous production process. Materials are fed into the quick-freezing tunnel via a conveyor belt, achieving continuous entry and exit and rapid freezing of the materials. The powdered precursor product passes through the liquid nitrogen tunnel on a conveyor belt within the liquid nitrogen tunnel at a speed of 0.4 to 1.2 m / min, preferably 0.6 to 1 m / min. The powdered precursor product remains in the liquid nitrogen tunnel for 5 to 15 minutes, preferably 6 to 10 minutes.

[0076] In some embodiments, drying comprises one or any combination of heating drying, vacuum drying, freeze drying, microwave drying, and supercritical fluid drying.

[0077] In some embodiments, drying includes freeze-drying. Freeze-drying is a drying method that involves freezing a water-containing material below its freezing point, converting the water into ice, and then removing the ice by converting it into vapor under a high vacuum. During the freeze-drying step, fine, evenly distributed ice crystals within the material are sublimated into water vapor under high vacuum conditions and removed, maximally preserving the composition, color, and aroma of the raw material. This further enhances the performance improvements achieved by the liquid nitrogen quick-freezing step for bulk powdered cosmetics. The small, evenly distributed ice crystals are easier to remove, reducing the generation of ice debris during the removal process and improving freeze-drying efficiency.

[0078] In some embodiments, drying comprises freeze drying and a combination of one or more of the following drying methods: heating drying, vacuum drying, microwave drying, or supercritical fluid drying.

[0079] Heating drying is one of the most common drying methods, which achieves drying by heating the material. Vacuum drying is a drying method in which the material is placed under negative pressure conditions and appropriately heated to the boiling point under negative pressure or cooled to solidify the material before drying. Microwave drying is a drying method that uses electromagnetic waves as a heating source and the material to be dried itself as a heating element. Supercritical fluid drying is a drying method that uses the high solubility of supercritical solvents to remove the solvent contained in porous solids. This application can select one or more drying methods according to the characteristics of the material.

[0080] When a high-temperature sensitive active substance is added to the material, the drying step in the embodiment of the present application is not performed at a temperature higher than 40° C. to ensure that the high-temperature sensitive active substance is not inactivated or partially inactivated during the drying step.

[0081] In some embodiments, the raw materials for preparing block powder cosmetics include a powder phase component, an oil phase component, and a water phase component;

[0082] The powder phase components include: one or more of fillers and colorants;

[0083] The oil phase components include: one or more of: emollients, antioxidants, and sunscreens;

[0084] The aqueous phase components include: one or more of solvents, thickeners, film formers, moisturizers, emulsifiers, preservatives, and active ingredients.

[0085] In some embodiments, the thickener and film-forming agent are selected from natural water-soluble polymers or their derivatives, synthetic water-based polymers, or water-based inorganic thickeners;

[0086] The natural water-soluble polymer or its derivative is selected from at least one of alginic acid, agar, carrageenan, xanthan gum, gellan gum, crisp chondrus crispus, xanthan gum, guar gum, tamarind gum, tara gum, gum arabic, tragacanth gum, tara gum, pectin, arabogalactan, wheat protein, soy protein, gelatin, casein, chitosan, curdlan, cyclodextrin, hyaluronic acid, konjac gum, tremella polysaccharide, codyl gum, microcrystalline cellulose, methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, starch phosphate, starch, sodium hydroxymethyl starch, sodium polyacrylate grafted starch, and hydroxypropyl guar gum;

[0087] The synthetic water-based polymer is selected from at least one of acrylates / C10-30 alkyl acrylate crosspolymer, carbomer, acrylates / octylacrylamide copolymer, acrylates / ethylhexyl acrylate copolymer, sodium acrylate / sodium acryloyldimethyl taurate copolymer, acrylates / octylacrylamide copolymer, styrene / acrylates copolymer, acrylates copolymer, hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer, polyacrylate crosspolymer-6, acrylates / stearyl ether-20 methacrylate copolymer, ammonium acryloyldimethyl taurate / beheneth-25 methacrylate crosspolymer, ammonium acrylates copolymer, sodium polyacrylate, sodium polyacryloyldimethyl taurate, polyacrylamide, polyvinyl pyrrolidone, polyvinyl alcohol, VP / VA copolymer, polyurethane-1, and polyurethane-35;

[0088] The aqueous inorganic thickener is selected from at least one of magnesium aluminum silicate, sodium magnesium lithium silicate, lithium magnesium silicate, sodium magnesium silicate, montmorillonite or their derivatives;

[0089] Based on the prepared bulk powder cosmetics, the mass percentage of the aqueous inorganic thickener and / or film-forming agent is 0.02-15%, preferably 0.05-5%.

[0090] In some embodiments, the emollient is selected from at least one of alcohols, silicone oils, mineral oils, synthetic oils, animal and plant oils, or derivatives thereof;

[0091] The animal or plant oil or its derivative is selected from at least one of glycerin, propylene glycol, dipropylene glycol, pentylene glycol, butylene glycol, ethylene glycol, hexylene glycol, sorbitol, xylitol, polyethylene glycol, dimethicone, caprylyl methicone, phenyl trimethicone, cetyl dimethicone, C30-45 alkyldimethylsilyl polypropyl silsesquioxane, bis-PEG-18 methyl ether dimethyl silane, white mineral oil, petrolatum, hydrogenated polyisobutene, lanolin and its derivatives, octyldodecanol, caprylic / capric triglyceride, ethylhexyl palmitate, bis-diglyceryl polyacyladipate-2, isononyl isononanoate, jojoba seed oil, coconut oil, hydrogenated coconut glycerides, meadowfoam seed oil, olive oil, squalane, C9-12 alkane, coconut oil caprylate / caprate, tocopheryl acetate, and methyl gluceth-10;

[0092] Based on the prepared block powder cosmetics, the mass percentage of the moisturizing agent is 0.1-40%, preferably 0.5-30%.

[0093] In some embodiments, the filler is selected from at least one of mica, talc, synthetic fluorphlogopite, kaolin, bentonite, boron nitride, bismuth oxychloride, silica, sodium potassium aluminum silicate, lauroyl lysine, magnesium stearate, magnesium myristate, calcium aluminum borosilicate, tin oxide, calcium sodium borosilicate, aluminum hydroxide, zinc stearate starch and its derivatives, and plastic microbeads;

[0094] The colorant is selected from at least one of iron oxides (CI 77499, CI 77491, CI 77492), titanium dioxide (CI 77891), iron blue (CI 77510), ultramarine (CI 77007), manganese violet (CI 77742), chromium oxide green (CI 77288), chromium hydroxide green, carmine (CI 75470), carbon black (CI 77266), CI 15850, CI 19140, CI 45410, CI 16035, CI 45380, CI 17200, CI 73360, CI 42090, and CI 47005;

[0095] Based on the prepared bulk powder cosmetics, the total mass percentage of the filler and the colorant is 50-99%, preferably 70-95%.

[0096] In some embodiments, the preservative is selected from at least one of phenoxyethanol, parabens, chlorphenesin, potassium sorbate, sodium benzoate, or a preservative synergist;

[0097] The preservative synergist is selected from at least one of caprylyl glycol, p-hydroxyacetophenone, ethylhexylglycerin, 1,2-hexanediol, caprylhydroxamic acid, 1,2-pentanediol, glyceryl caprylate, and cymene.

[0098] In some embodiments, the active can be selected from high temperature sensitive actives or high temperature insensitive actives.

[0099] In some embodiments, the high-temperature sensitive active is unstable, has reduced activity, or loses activity in an environment above 40° C. For example, the high-temperature sensitive active can be selected from at least one of a polypeptide active, astaxanthin, vitamin A or its derivatives, vitamin C or its derivatives, and arbutin.

[0100] In existing powder preparation technologies, the material is usually heated before filling to increase the fluidity of the material and facilitate filling and transportation. The heating operation determines that active substances that are sensitive to high temperatures cannot be used in the powder raw materials. For example, active substances such as polypeptide active substances, astaxanthin, vitamin A alcohol, vitamin C or its derivatives, arbutin, etc. cannot be added as raw materials, or even if added, some or all of their activity will be lost due to the heating step. The preparation process of the present application does not include any high-temperature process. The filling step can be performed at low temperature or room temperature, and high-temperature sensitive active substances can be added to the material.

[0101] In some embodiments, the solvent is water or a mixture of water and an organic solvent.

[0102] In some embodiments, the thickener is an inorganic thickener; preferably, the inorganic thickener is at least one of magnesium aluminum silicate, lithium sodium magnesium silicate, lithium magnesium silicate, sodium magnesium silicate, montmorillonite, or a derivative thereof.

[0103] In the prior art, natural polysaccharides are often used as thickeners for powder products because of their good thickening and bonding effects. Inorganic thickeners are not as good as natural polysaccharides in bonding effects. If they are used alone as thickeners, problems such as product cracking and poor drop resistance will occur. However, natural polysaccharides also increase the microbial risk of powder products, which is not conducive to the long-term storage of powder products. In the embodiments of the present application, in the air pressure feeding and extrusion drying operations, external forces are used to increase the density of the material body, and due to the reduction in the amount of solvent used, the adverse effects of the solvent removal step on the internal bonding stability of the material body are also reduced. Therefore, even if an inorganic thickener with a bonding effect not as good as that of natural polysaccharides is used, the powder product finally prepared will not crack or have poor drop resistance. The use of inorganic thickeners instead of natural polysaccharides can reduce microbial risks and increase the long-term storage stability of powder products.

[0104] In a second aspect, embodiments of the present application provide a bulk powder cosmetic, prepared by the method of embodiments of the first aspect of the present application. The bulk powder cosmetic provided herein is prepared by using a pneumatic feeding device to fill a preset amount into a mold, followed by extrusion and drying of the material in the mold. This effectively avoids problems such as ice residue and shrinkage deformation during the desolvation process, as well as cracking, poor drop resistance, pores, and softness in the finished product. The powder surface exhibits excellent fine relief, and high-temperature-sensitive active ingredients can be added.

[0105] In some embodiments, the block powder cosmetics are selected from pressed powder, blush, eye shadow or highlighter. The block powder cosmetics may also include products with other functions. Example

[0106] The following examples describe the present disclosure in more detail. These examples are intended for illustrative purposes only, as various modifications and variations within the scope of the present disclosure will be apparent to those skilled in the art. Unless otherwise stated, all parts, percentages, and ratios reported in the following examples are by mass, and all reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further processing. The instruments used in the examples are commercially available.

[0107] Recipes 1-4

[0108] Illustratively, this application provides the raw material composition, proportions and mixing methods for preparing four block powder cosmetics.

[0109] The raw material components of the bulk powder cosmetic formula 1 are shown in Table 1:

[0110] Table 1

[0111]

[0112] Mixing: (1) Heat and disperse phase A evenly, temperature 75±5℃; (2) Add phase B to phase A and homogenize and emulsify, temperature 75±5℃; (3) Add phase C to (2) and mix evenly, temperature 75±5℃; (4) Cool the material to 50±5℃; (5) Add D (needs to be pre-dissolved), E, and F to (4) and mix evenly, and vacuum degas at 50±5℃ to obtain the material;

[0113] The raw material components of the bulk powder cosmetic formula 2 are shown in Table 2:

[0114] Table 2

[0115]

[0116] Mixing: (1) Heat and disperse phase A evenly, temperature 75±5℃; (2) Add phase B to phase A and emulsify homogeneously, temperature 75±5℃; (3) Add phase C to (2) and mix evenly, temperature 75±5℃; (4) Cool the material to 50±5℃; (5) Add D (needs to be pre-dissolved) and E to (4), mix evenly, and vacuum degas at 50±5℃ to obtain the material;

[0117] The raw material components of the bulk powder cosmetic formula 3 are shown in Table 3:

[0118] Table 3

[0119]

[0120] Mixing: (1) Heat and disperse phase A evenly, temperature 75±5℃; (2) Add phase B to phase A and emulsify homogeneously, temperature 75±5℃; (3) Add phase C to (2) and mix evenly, temperature 75±5℃; (4) Cool the material to 50±5℃; (5) Add D (needs to be pre-dissolved) and E to (4), mix evenly, and vacuum degas at 50±5℃ to obtain the material;

[0121] The raw material components of the bulk powder cosmetic formula 4 are shown in Table 4:

[0122] Table 4

[0123]

[0124] Mixing: (1) Heat and disperse phase A evenly, temperature 75±5℃; (2) Add phase B to phase A and emulsify homogeneously, temperature 75±5℃; (3) Add phase C to (2) and mix evenly, temperature 75±5℃; (4) Cool the material to 50±5℃; (5) Add D (needs to be pre-dissolved) and E to (4), mix evenly, and vacuum degas at 50±5℃ to obtain the material.

[0125] Examples 1 to 12

[0126] The preparation of bulk powder cosmetics is carried out as follows:

[0127] Mixing: providing raw materials according to the raw material components of the bulk powder cosmetics formula, mixing the raw materials according to the mixing steps to obtain a material body;

[0128] Filling and pre-curing: The material body is filled into the mold according to the preset amount through the air pressure feeding device, and the material body is subjected to pressure filtration and negative pressure suction to reduce the solvent content in the material body to 30-50% of the original solvent content in the material body before pressure filtration and negative pressure suction, thereby obtaining the powder masterbatch pre-cured in the mold;

[0129] Freezing: Freeze the pre-cured powder masterbatch at low temperature. The freezing step is carried out in a liquid nitrogen tunnel.

[0130] Demolding and drying: separating the frozen powdered masterbatch from the mold and drying it to obtain a bulk powdered cosmetic; or drying the frozen powdered masterbatch and separating it from the mold to obtain a bulk powdered cosmetic, wherein the solvent content in the bulk powdered cosmetic is less than 5%.

[0131] Among them, the parameters involved in Examples 1 to 12, such as the viscosity of the material, the pressure in the pneumatic feeding device, the pressure of the material filter press and negative pressure suction, the temperature inside the liquid nitrogen tunnel in the step of solidifying and freezing the powder master product at low temperature, the speed of the powder master product in the liquid nitrogen tunnel, the transit time, and the drying method, are shown in Table 5.

[0132] Comparative Examples 1 to 5

[0133] The difference between Comparative Example 1 and Example 4 is that the pneumatic feeding device is not used for feeding, but gravity filling is performed at room temperature of 25° C., and the material body is not subjected to pressure filtration and negative pressure suction.

[0134] The difference between Comparative Example 2 and Example 4 is that the pneumatic feeding device is not used for feeding, but the material body is heated to 50° C. and then gravity filling is performed, and the material body is not subjected to pressure filtration and negative pressure suction.

[0135] The difference between Comparative Example 3 and Example 4 is that the pneumatic feeding device is not used for feeding, but the material body is heated to 90° C. and then gravity filling is performed, and the material body is not subjected to pressure filtration and negative pressure suction.

[0136] The difference between Comparative Example 4 and Example 4 is that solvent water is added to the raw material components of Formula 4 to reduce the viscosity of the material obtained by mixing to 5000 cP. Then, instead of using a pneumatic feeding device to feed the material, the material is heated to 50°C and then gravity filled, and the material is not subjected to filter pressing and negative pressure suction.

[0137] The difference between Comparative Example 5 and Example 1 is that solvent water is added to the raw material components of Formula 1 to reduce the viscosity of the material obtained by mixing to 3000 cP. Then, instead of using a pneumatic feeding device to feed the material, the material is heated to 50°C and then gravity filled, and the material is not subjected to filter pressing and negative pressure suction.

[0138] Among them, the parameters involved in Comparative Examples 1 to 5, such as the viscosity of the material, the pressure in the air pressure feeding device, the pressure of the material filter press and negative pressure suction, the temperature inside the liquid nitrogen tunnel in the step of solidifying and freezing the powder master product at low temperature, the speed of the powder master product in the liquid nitrogen tunnel, the transit time, and the drying method, are shown in Table 5.

[0139] Table 5 Process parameters of Examples 1 to 12 and Comparative Examples 1 to 5

[0140]

[0141] Test section

[0142] Pressed compacts were prepared according to the methods of Examples 1 to 12 and Comparative Examples 1 to 5. 100 pressed compacts were prepared for each Example or Comparative Example. Appearance observation, diameter shrinkage test, and drop test were performed. The presence of microbial risks caused by natural polysaccharides and the possibility of inactivation or partial inactivation of high-temperature sensitive active ingredients were also recorded.

[0143] 1) Appearance observation

[0144] Observe the appearance of the powder cake with the naked eye or with the help of a microscope, including the surface relief effect. Pay attention to whether the sharp corners of the fine relief on the surface of the powder cake are completely filled, whether there are bubbles, whether the bottom of the powder cake is flat, and whether the powder texture is uniform and dense.

[0145] The recorded appearance is based on the observation of more than 90% of the 100 pressed powders.

[0146] Diameter shrinkage

[0147] Use a vernier caliper to measure the mold diameter D and the diameter d of the resulting powder cake. Because this application utilizes pneumatic feeding, filter pressing, and negative pressure suction, it can be assumed that the mold is fully filled with material upon completion of the filling and pre-curing steps. Therefore, the diameter of the filling mold is used as the diameter of the powder product before freezing, demolding, and drying.

[0148] The diameter shrinkage is calculated using the following formula:

[0149] Diameter shrinkage = [(D - d)\D]* 100%

[0150] Where D is the diameter of the filling mold and d is the diameter of the prepared powder cake.

[0151] The reported diameter shrinkage is the average of the values measured for 100 pressed powders.

[0152] Drop detection

[0153] Adjust the rotating screws on the drop test platform to adjust the flat plate to the 30cm scale; place the powder block with the front side facing up in the center of the test height.

[0154] Perform the first drop test: Press the test bench button to drop the powder block onto a hard surface. Pick up the fallen powder block and inspect its surface for cracks or breaks. If any are found, discontinue the drop test. If no abnormalities are detected, proceed to the second drop test. The procedure for this second drop test is the same as for the first. If any are found, discontinue the drop test. If no abnormalities are detected, proceed to the third drop test. The procedure for this third drop test is the same as for the first.

[0155] The ratio of the number of powder compacts that broke in each drop test to the total number of powder compacts in that drop test is the breakage rate for each drop test. The first breakage rate, second breakage rate, and third breakage rate of Examples 1 to 12 and Comparative Examples 1 to 5 are recorded respectively.

[0156] Microbial risks posed by natural polysaccharides

[0157] If the powder raw materials do not contain natural polysaccharide components, it is considered that the powder does not have the microbial risk caused by natural polysaccharides; if the powder raw materials contain natural polysaccharide components, it is considered that the powder has the possibility of microbial risk caused by natural polysaccharides.

[0158] High temperature sensitive active ingredients

[0159] If the pressed powder preparation process includes a step where the temperature exceeds 40°C, the heat-sensitive active ingredient is considered to be inactivated or partially inactivated. If the pressed powder preparation process does not include a step where the temperature exceeds 40°C, the heat-sensitive active ingredient is considered to be active.

[0160] The test results of Examples 1 to 12 and Comparative Examples 1 to 5 are recorded in Table 6.

[0161] Table 6 Test results of Examples 1 to 12 and Comparative Examples 1 to 5

[0162]

[0163] As shown in the test results in Table 6, Examples 1-12 employ the method for preparing bulk powder cosmetics provided herein. The material is quantitatively filled into a mold via a pneumatic feeding device, and extrusion drying is employed to remove some of the solvent from the material, achieving pre-curing. The bulk powder cosmetics are then frozen, dried, and demolded to obtain the bulk powder cosmetics. Compared to Comparative Examples 1-5, which did not employ the method, Examples 1-12 demonstrate significant improvements in filling efficiency, mold relief filling, and the appearance, texture, and skin feel of the resulting bulk powder cosmetics. They also significantly improve diameter shrinkage during the preparation process and reduce the powder drop test breakage rate. Furthermore, they provide a feasible solution for avoiding microbial risks posed by natural polysaccharides and the use of high-temperature-sensitive active ingredients in powder products.

[0164] The average diameter shrinkage during the powder preparation process of Examples 1-12 was less than 1%, and the sum of the breakage rates in three drop tests did not exceed 15%. The rendering of fine relief on the surface of the powder was significantly better than that of Comparative Examples 1-5. However, since Comparative Examples 1-5 did not adopt the preparation method of the present application, they could not be effectively filled and produced due to the low solvent content and high viscosity of the filling material. Even by heating the material before filling or adding solvent to reduce the viscosity of the material, the performance data of the block powder cosmetics produced by these methods were still significantly inferior to those of Examples 1-12 of the present application in terms of diameter shrinkage, breakage rate in drop tests, and other aspects.

[0165] Furthermore, in the method for preparing bulk powder cosmetics provided herein, parameters such as the pressure of the pneumatic feeding device for auxiliary feeding, the pressure of the material during filter pressing and negative pressure suction, and the temperature and time control for curing the powdered product at low temperatures also affect the technical effects of the present application. This application also provides optimal ranges for these process parameters to further optimize the various properties of the bulk powder cosmetics prepared according to the method provided herein. For example, in Examples 1-4, when the material viscosity is between 10,000 and 30,000 cP, the feed pressure in the pneumatic feeding device is between 0.02 and 0.1 MPa, the pressure parameter of the filtration during extrusion drying is between 0.05 and 3 MPa, the pressure parameter of the negative pressure suction is between 0.02 and 0.1 MPa, the temperature inside the liquid nitrogen tunnel is between -120°C and -70°C, and the powdered product is conveyed through the liquid nitrogen tunnel on a conveyor belt within the liquid nitrogen tunnel at a speed of 0.4 to 1.2 m / min for a transit time of 5 to 15 minutes. The resulting block-shaped powdered cosmetic has embossed sharp corners that are completely filled and free of bubbles, a flat bottom, a uniform and dense powder texture, excellent drop resistance, and an average diameter shrinkage rate of less than 0.2%.

[0166] The preparation method of block powder cosmetics provided in this application successfully solves technical problems such as shrinkage and deformation of powder products during the preparation and desolvation process, cracking of the prepared powder products, poor drop resistance, pores and softness. At the same time, it also enables block powder cosmetics to avoid the microbial risks caused by natural polysaccharides and the addition of high-temperature sensitive active substances, providing better prospects for the development and application of block powder cosmetics.

[0167] The above is only a specific embodiment of the present application. Those skilled in the art will clearly understand that for the convenience and brevity of description, the specific working process described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. It should be understood that the scope of protection of the present application is not limited to this. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the scope of protection of this application.

Claims

1. A method for preparing bulk powder cosmetics, characterized in that: The steps include: Mixing: Providing raw materials for preparing bulk powder cosmetics, the raw materials include powder phase components, oil phase components and water phase components, and mixing the raw materials to obtain a material body; the viscosity of the material body is below 30,000 cP; Filling and pre-curing: The material body is filled into the mold according to a preset amount through an air pressure feeding device, and the material body is extruded and dried to obtain a powder masterbatch pre-cured in the mold; the pressure in the air pressure feeding device is 0.02-0.1 MPa; the extrusion drying includes performing pressure filtration and negative pressure suction on the material body in the mold, the pressure parameters of the pressure filtration are 0.05-3 MPa, and the pressure parameters of the negative pressure suction are 0.02-0.1 MPa; Freezing: freezing the pre-cured powdered product at low temperature; the freezing is carried out in a liquid nitrogen tunnel at -120 to -70°C, and the powdered product passes through the liquid nitrogen tunnel on a conveyor belt in the liquid nitrogen tunnel at a speed of 0.4 to 1.2 m / min for 5 to 15 minutes; Demolding and drying: separating the frozen powdered product from the mold and drying it to obtain a bulk powdered cosmetic; or drying the frozen powdered product and separating it from the mold to obtain a bulk powdered cosmetic; The temperature of the drying step is lower than 40°C; The drying includes freeze drying, or a combination of freeze drying and one or more of the following drying methods: heating drying, vacuum drying, microwave drying, and supercritical fluid drying; The solvent content in the prepared bulk powder cosmetics is less than 1%.

2. The method for preparing bulk powder cosmetics according to claim 1, characterized in that: The step of filling the material body into the mold according to a preset amount via the air pressure feeding device includes: pressing or sucking the material body into the mold by the action of air pressure.

3. The method for preparing bulk powder cosmetics according to claim 2, characterized in that: The viscosity of the material is 10000 cP~25000 cP; the pressure in the air pressure feeding device is 0.04~0.08 MPa.

4. The method for preparing bulk powder cosmetics according to claim 1, wherein: The extrusion drying comprises performing filter pressing on the material body in the mold to allow at least a portion of the solvent to be dialyzed out of the material body, and transferring the dialyzed solvent during or after the filter pressing.

5. The method for preparing bulk powder cosmetics according to claim 4, characterized in that: The pressure parameter of the filter press is 0.2~1.5Mpa; the pressure parameter of the negative pressure suction is 0.05~0.08Mpa.

6. The method for preparing bulk powder cosmetics according to claim 5, characterized in that: In the step of simultaneously performing filter pressing and negative pressure suction on the material body in the mold, the solvent content in the material body is reduced to 30-80% of the original solvent content in the material body before filter pressing and negative pressure suction, thereby obtaining a powder masterbatch pre-cured in the mold.

7. The method for preparing bulk powder cosmetics according to claim 6, characterized in that: In the step of simultaneously performing filter pressing and vacuum suction on the material body in the mold, the content of the solvent in the material body is reduced to 30-50% of the original solvent content in the material body before filter pressing and vacuum suction.

8. The method for preparing bulk powder cosmetics according to claim 1, characterized in that: The temperature inside the liquid nitrogen tunnel is -95~-80°C.

9. The method for preparing bulk powder cosmetics according to claim 8, characterized in that: The powdered precursor passes through the liquid nitrogen tunnel on a conveyor belt in the liquid nitrogen tunnel at a speed of 0.6 to 1 m / min, and the powdered precursor passes through the liquid nitrogen tunnel for 6 to 10 minutes.

10. The method for preparing bulk powder cosmetics according to claim 1, characterized in that: The powder phase components include: one or more of fillers and colorants; The oil phase components include: one or more of: moisturizing agents, antioxidants, and sunscreens; The aqueous phase components include: one or more of a solvent, a thickener, a film former, a moisturizer, an emulsifier, a preservative, and an active ingredient.

11. The method for preparing bulk powder cosmetics according to claim 10, characterized in that: The thickener and film-forming agent are selected from natural water-soluble polymers or their derivatives, synthetic water-based polymers or water-based inorganic thickeners; The natural water-soluble polymer or its derivative is selected from at least one of alginic acid, agar, carrageenan, xanthan gum, gellan gum, crisp chondrus crispus, xanthan gum, guar gum, tamarind gum, tara gum, gum arabic, tragacanth gum, tara gum, pectin, arabogalactan, wheat protein, soy protein, gelatin, casein, chitosan, curdlan, cyclodextrin, hyaluronic acid, konjac gum, tremella polysaccharide, codyl gum, microcrystalline cellulose, methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, starch phosphate, starch, sodium hydroxymethyl starch, sodium polyacrylate grafted starch, and hydroxypropyl guar gum; The synthetic water-based polymer is selected from at least one of acrylates / C10-30 alkyl acrylate crosspolymer, carbomer, acrylates / octylacrylamide copolymer, acrylates / ethylhexyl acrylate copolymer, sodium acrylate / sodium acryloyldimethyl taurate copolymer, styrene / acrylates copolymer, hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer, polyacrylate crosspolymer-6, acrylates / stearyl ether-20 methacrylate copolymer, ammonium acryloyldimethyl taurate / beheneth-25 methacrylate crosspolymer, sodium polyacrylate, sodium polyacryloyldimethyl taurate, polyacrylamide, polyvinyl pyrrolidone, polyvinyl alcohol, VP / VA copolymer, polyurethane-1, and polyurethane-35; The aqueous inorganic thickener is selected from at least one of magnesium aluminum silicate, sodium magnesium lithium silicate, lithium magnesium silicate, sodium magnesium silicate, montmorillonite or its derivatives; Based on the prepared bulk powder cosmetics, the mass percentage of the aqueous inorganic thickener and / or film-forming agent is 0.02-15%.

12. The method for preparing bulk powder cosmetics according to claim 11, characterized in that: Based on the prepared bulk powder cosmetics, the mass percentage of the aqueous inorganic thickener and / or film-forming agent is 0.05-5%.

13. The method for preparing bulk powder cosmetics according to claim 10, characterized in that: The emollient and moisturizing agent is selected from at least one of alcohols, silicone oil, mineral oil, synthetic oil, and animal and vegetable oils; Based on the prepared block powder cosmetics, the mass percentage of the emollient and moisturizing agent is 0.1-40%.

14. The method for preparing bulk powder cosmetics according to claim 13, characterized in that: Based on the prepared block powder cosmetics, the mass percentage of the emollient and moisturizing agent is 0.5-30%.

15. The method for preparing bulk powder cosmetics according to claim 10, characterized in that: The filler is selected from at least one of mica, talc, kaolin, bentonite, boron nitride, bismuth oxychloride, silica, sodium potassium aluminum silicate, lauroyl lysine, magnesium stearate, magnesium myristate, calcium aluminum borosilicate, tin oxide, calcium sodium borosilicate, aluminum hydroxide, zinc stearate starch, and plastic microbeads; The colorant is selected from at least one of iron oxide CI 77499, iron oxide CI 77491, iron oxide CI 77492, titanium dioxide CI 77891, iron blue CI 77510, ultramarine CI 77007, manganese violet CI 77742, chromium oxide green CI 77288, chromium hydroxide green, carmine CI 75470, carbon black CI 77266, CI 15850, CI 19140, CI 45410, CI 16035, CI 45380, CI 17200, CI 73360, CI 42090, and CI 47005; Based on the prepared bulk powder cosmetics, the total mass percentage of the filler and the colorant is 50-99%.

16. The method for preparing bulk powder cosmetics according to claim 15, characterized in that: Based on the prepared bulk powder cosmetics, the total mass percentage of the filler and the colorant is 70-95%.

17. The method for preparing bulk powder cosmetics according to claim 10, characterized in that: The preservative is selected from at least one of phenoxyethanol, parabens, chlorphenesin, potassium sorbate, sodium benzoate or preservative synergists; The antiseptic synergist is selected from at least one of caprylyl glycol, p-hydroxyacetophenone, ethylhexylglycerin, 1,2-hexanediol, caprylhydroxamic acid, 1,2-pentanediol, glyceryl caprylate, and cymene.

18. The method for preparing bulk powder cosmetics according to claim 10, characterized in that: The active substance is selected from a high temperature sensitive active substance or a high temperature insensitive active substance.

19. The method for preparing bulk powder cosmetics according to claim 18, characterized in that: The high temperature sensitive active substance is selected from at least one of polypeptide active substances, astaxanthin, vitamin A alcohol or its derivatives, vitamin C or its derivatives, and arbutin.

20. The method for preparing bulk powder cosmetics according to claim 10, characterized in that: The solvent is water or a mixture of water and an organic solvent.

21. The method for preparing bulk powder cosmetics according to claim 10, characterized in that: The thickener is an inorganic thickener.

22. The method for preparing bulk powder cosmetics according to claim 21, characterized in that: The inorganic thickener is at least one of magnesium aluminum silicate, sodium magnesium lithium silicate, lithium magnesium silicate, sodium magnesium silicate, and montmorillonite.

23. A block powder cosmetic, characterized in that: The method is prepared by any one of claims 1 to 22.

24. The block powder cosmetic according to claim 23, characterized in that: The block powder cosmetics are selected from pressed powder, blush, eye shadow or highlighter powder.

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