Bottom support for preparing three-dimensional powder block, three-dimensional powder block and preparation method of three-dimensional powder block

Abstract

The invention provides a bottom support for preparing a three-dimensional powder block, the three-dimensional powder block and a preparation method of the three-dimensional powder block. Belongs to the technical field of makeup product manufacturing. The bottom support comprises a central area, a middle area and an edge area which are connected in sequence, the middle area is arranged around the circumferential direction of the central area, and the edge area is arranged around the circumferential direction of the middle area; the central area is provided with a plurality of first through holes which are arranged at intervals, the middle area is provided with a plurality of second through holes which are arranged at intervals, and the first through holes and the second through holes jointly form a mesh structure; the meshes allow mixed fluid of the powder block to enter so as to realize integrated combination of the powder block and the bottom support; and the central area and the middle area are not on the same plane. According to the preparation method, an inverted pressing type process is adopted, and integrated combination of the powder block and the bottom support can be achieved without additional adhesives; the problems of insufficient surface fineness, pattern fidelity and structural stability of powder blocks in the prior art are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cosmetic product manufacturing, in particular to a base for preparing a three-dimensional powder block, a three-dimensional powder block and a preparation method thereof. BACKGROUND

[0002] With the continuous improvement of consumer aesthetic requirements for cosmetic products, powder blocks with three-dimensional shapes have become mainstream products in the market due to their visual impact and interesting use. However, the existing preparation technology of three-dimensional powder blocks still has significant bottlenecks in terms of balancing surface fineness and three-dimensional pattern fidelity.

[0003] For example, to prevent powder adhesion to the mold, the traditional pressing process usually adopts a method of covering a layer of film cloth between the powder and the pressing head for pressing. However, this method inevitably leaves the texture of the film cloth on the surface of the powder block, resulting in a high micro-roughness of the powder block surface, which is difficult to achieve the smooth and delicate texture pursued by high-end cosmetics. In addition, limited by the elastic deformation and ductility of the film cloth, the edges of some complex or delicate three-dimensional patterns are prone to become blurred, and the depth and level of the relief are thus severely affected, which cannot achieve high-fidelity pattern replication.

[0004] To solve the above problems, some technical solutions attempt to use a slurry containing a specific gel system (such as containing chondrus crispus and xanthan gum), and combine pressing, freezing and segmented drying processes to improve the structure of the powder block. However, this type of technical solution still has obvious defects. First, the conventional pressing and static or vacuum drying process used by it fails to actively manage and control the huge shrinkage stress of the powder due to capillary force during dehydration, resulting in structural instability problems such as edge shrinkage and cracking in the product on a macroscopic level. Secondly, at the micro level, this solution still cannot guarantee extreme surface fineness and high-precision pattern fidelity without using a film cloth. Finally, this solution fails to reveal the internal synergistic relationship between the gel system, the physical properties of the powder, and the specific process flow, so it cannot systematically solve the fundamental contradiction between the high fluidity, high formability and anti-shrinkage of the powder material, and usually still needs to rely on additional adhesives to ensure the combination of the powder and the substrate, which not only brings safety risks such as heavy metal residues, but also may cause dry and harsh skin feel, affecting the use experience. SUMMARY

[0005] The purpose of the present application is to provide a base for preparing a three-dimensional powder block, a three-dimensional powder block and a preparation method thereof, aiming to solve the technical problem that the existing preparation technology of three-dimensional cosmetic powder blocks cannot simultaneously achieve high surface fineness, high-fidelity three-dimensional patterns and low shrinkage rate of structural stability without using additional adhesives.

[0006] To solve the above technical problems, the present application provides the technical solutions as follows: In a first aspect, the present application provides a base for preparing a three-dimensional powder block, the base 1 comprising a central region 11, an intermediate region 12 and an edge region 13 connected in sequence, the intermediate region 12 being arranged in a circumferential direction around the central region 11, and the edge region 13 being arranged in a circumferential direction around the intermediate region 12; the central region 11 is provided with a plurality of first through holes 111 arranged at intervals, the intermediate region 12 is provided with a plurality of second through holes 121 arranged at intervals, and the plurality of first through holes 111 and the plurality of second through holes 121 together form a mesh structure; the mesh structure allows the mixed fluid of the powder block to enter to realize the integrated combination of the powder block and the base; the central region 11 and the intermediate region 12 are not in the same plane.

[0007] The intermediate region 12 is higher than the central region 11. In the finished product of the three-dimensional powder block, the central region 11 protrudes outward more than the intermediate region 12 when viewed from the outside of the base.

[0008] The plurality of first through holes 111 and the plurality of second through holes 121 are centrally symmetrically distributed; each of the first through holes 111 and the second through holes 121 is in the shape of a regular geometric shape (preferably a sector, a rectangle, a circle, an ellipse or a sector ring).

[0009] The outer side of the edge region 13 extends in a radial direction to form a stop edge 131.

[0010] The top view of the base is in any one of a circular shape, an elliptical shape, a rectangular shape, a regular polygonal shape or an irregular shape 1.

[0011] The base is made of plastic injection molding or a metal disc; the plastic is selected from one of polypropylene, ABS and polyethylene terephthalate. The metal can be aluminum, aluminum alloy, tinplate or stainless steel.

[0012] The central region 11, the intermediate region 12 and the edge region 13 can be an integrally formed structure, and optionally, the intermediate region 12 is in the shape of a ring and arranged in a circumferential direction around the central region 11, and the edge region 13 is in the shape of a ring and arranged in a circumferential direction around the intermediate region 12.

[0013] In a second aspect, the present application provides a preparation method of a high-fidelity three-dimensional powder block by reverse pressure, comprising the following steps: S1, preparing a mixed fluid: preparing a mixed fluid containing a powder component and a water-oil continuous gel, wherein the powder component contains a base and a colored phase, and the water-oil continuous gel contains an aqueous phase and an oil phase; S2, providing a combined mold: providing a set of combined molds, which includes a mold shell 2 made of flexible material and provided with a trough 21, and a bottom support 1 as described above which is matched in size with the mold shell; the bottom support 1 is configured to be embedded in the opening of the trough 21, and its height is set to be lower than the depth of the trough 21, so that when the bottom support 1 is buckled to the mold shell 2, there is a gap between the bottom support 1 and the bottom of the trough 21, providing space for the redistribution and compaction of the mixed fluid under pressure; S3, pouring and combining: pouring the mixed fluid into the trough 21 of the mold shell 2, and then covering the surface of the mixed fluid with the bottom support 1; S4, pressure dewatering: applying pressure to the mixed fluid through the bottom support 1, so that the water in the fluid is discharged through the mesh formed by the first through hole 111 and the second through hole 121 of the bottom support 1, and part of the fluid enters the mesh, realizing the preliminary combination of the powder block and the bottom support 1; S5, freezing and demolding: freezing and shaping the entire mold after pressure dewatering, and then using the flexibility of the mold shell 2 to remove the frozen powder block that has been preliminarily combined with the bottom support 1 from the trough 21; S6, drying the powder block after freezing and shaping, and the powder block is obtained.

[0014] In S1, the components of the mixed fluid include, by weight percentage: Base material: 50-65%; Color phase: 1-10%; Water phase: 5-25%; Oil phase: 5-10%; Preservative: 0.1-1.0%; Solvent: make up to 100%.

[0015] The base material includes one or more of synthetic fluorphlogopite, mica, HDI / trihydroxymethyl hexyl lactone cross-linked polymer, nylon-12, polymethyl methacrylate, vinyl polydimethylsiloxane / polymethylsiloxane silsesquioxane cross-linked polymer, boron nitride, lauroyl lysine.

[0016] Preferably, the base material includes synthetic fluorphlogopite, mica and HDI / trihydroxymethyl hexyl lactone cross-linked polymer.

[0017] In the mixed fluid, by weight percentage: The content of synthetic fluorphlogopite is 15-40%; The content of mica is 10-40%; The content of HDI / trihydroxymethyl hexyl lactone cross-linked polymer is 5-12%.

[0018] The coloring phase comprises color powder and / or pearl powder.

[0019] The color powder is selected from one or more of CI 73360, CI 77891, CI 77491, CI 77007, CI 77492, CI 77499.

[0020] The aqueous phase comprises a humectant, a colloidal thickening agent, an aqueous solution of inorganic salt ion source and a surfactant.

[0021] In the mixed fluid, by weight percentage: The humectant content is 4.5-10%; The total content of the colloidal thickening agent is 0.3-4.5%; The content of the aqueous solution of inorganic salt ion source is 1-10%; The content of the surfactant is 0.5-3%.

[0022] The humectant is selected from one or more of glycerin, propylene glycol, butylene glycol, pentylene glycol; The colloidal thickening agent is selected from one or more of a mixture of chondrus crispus and sodium chloride, xanthan gum, gellan gum.

[0023] The aqueous solution of inorganic salt ion source is seawater.

[0024] The surfactant is selected from one or more of sodium stearate, sodium distearate, disodium cocoyl glutamate.

[0025] The oil phase comprises an emulsifier and an emollient.

[0026] The emulsifier is selected from one or more of polysorbate-80, polysorbate-60, polysorbate-20, C12-20 acid PEG-8 ester; The emollient is selected from one or more of octyldodecyl stearoyl oxy stearate, cetostearyl alcohol ethylhexanoate, squalane, hydrogenated polyisobutene.

[0027] The preservative is selected from one or more of phenoxyethanol, caprylyl glycol, ethylhexylglycerin; and the solvent is deionized water.

[0028] As an embodiment of the present application, the components of the mixed fluid comprise, by weight percentage:

[0029] In the mixture of chondrus crispus and sodium chloride, the mass ratio of chondrus crispus to sodium chloride is 2:1-1:2.

[0030] The mixed fluid in step S1 is prepared by a method comprising the following steps: S11, preparing powder A: after mixing the base components uniformly, adding the color powder in the color phase, and performing high-speed mixing and dispersion; then adding the pearl powder, and performing low-speed mixing to obtain uniform powder A; S12, preparing the water phase: mixing deionized water, humectants, and gum thickener, heating and stirring until the gum is completely dissolved to form a uniform gel; then adding an aqueous solution of inorganic salt ion source, stirring until a thixotropic gel is formed; then adding a surfactant, stirring and dispersing uniformly to obtain the water phase; S13, preparing the oil phase: mixing the emulsifier and emollient, heating and stirring until completely melted to obtain the oil phase; S14, preparing the water-oil continuous gel B: pouring the oil phase into the water phase, performing high-speed homogenization to form a stable emulsion; after cooling, adding a preservative, and performing high-speed homogenization again to obtain the water-oil continuous gel B; S15, fluid preparation: mixing the powder A with the water-oil continuous gel B, stirring under heating conditions to form a flowable uniform mixed fluid.

[0031] The high-speed mixing and dispersion speed is 1000-2000 r / min, and the mixing is performed 3-5 times, each time for 1-3 minutes; the low-speed mixing speed is 300-800 r / min, and the mixing is performed 2-3 times, each time for 1-3 minutes.

[0032] In step S12, the heating temperature is 60-80°C, and the stirring speed is 500-1000 r / min.

[0033] In step S14, the high-speed homogenization speed is 3000-5000 r / min, and the time is 3-5 minutes.

[0034] In step S14, the emulsion is cooled to 35-45°C before adding the preservative.

[0035] In step S15, the heating temperature is 40-60°C.

[0036] The combined mold further comprises a sleeve 3, which is sleeved outside the mold shell 2.

[0037] The middle part of the sleeve 3 is provided with a receiving groove 31 for accommodating the mold shell 2.

[0038] The mold shell 2 is optionally a silica gel shell.

[0039] In step S4, the pressure applied by the bottom support 1 is 0.1 MPa to 0.5 MPa.

[0040] The temperature of the freezing and shaping treatment in step S5 is -40℃ to -65℃. The freezing and shaping treatment in step S5 is performed for 10 minutes to 15 minutes.

[0041] The drying treatment in step S6 is a segmented drying treatment, which includes a low-temperature drying stage and a temperature-increasing drying stage.

[0042] The low-temperature drying step is to slowly increase the temperature from -45℃ to 0℃ (at a rate of 5-10℃ / h) and control the relative humidity at 30-50%, and then perform low-temperature sublimation drying on the powder block for 4-8 hours under the above conditions; The temperature-increasing drying stage: after the low-temperature drying is completed, the temperature is increased from 0℃ to 45℃, and then the powder block is dried for 4-8 hours at the temperature.

[0043] The application also provides a three-dimensional powder block prepared by the preparation method.

[0044] The powder layer contains gel network residues formed by at least one of wrinkle chondrus and xanthan gum, and the powder layer does not contain an adhesive component added additionally to realize the adhesion between the powder layer and the bottom support.

[0045] The base material part of the application selects synthetic fluorine phlogopite, and the powder is a flaky powder with a diameter-thickness ratio greater than 50. The high diameter-thickness ratio geometry enables the powder particles to be arranged in parallel to the mold surface in the gel network during the subsequent forming process, thereby effectively resisting the transverse shrinkage stress caused by dehydration at the micro level, which is one of the key factors to ensure that the final powder block product has low shrinkage.

[0046] The water phase includes a humectant, a colloidal thickening agent, an aqueous solution of an inorganic salt ion source, and a surfactant; wrinkle chondrus and xanthan gum.

[0047] Compared with the prior art, the technical scheme provided by the application has the following beneficial effects: 1. The application uses a membrane cloth-free reverse pressure dehydration process to fundamentally eliminate the problem of texture left on the surface of the powder block caused by the use of membrane cloth in the traditional process, thereby obtaining a powder block with extremely smooth and delicate surface; at the same time, combined with the rapid freezing and shaping technology, the fine three-dimensional pattern formed by the mixed fluid in the mold can be instantly locked, which effectively prevents the pattern from collapsing or the edge from blurring due to stress release in the subsequent drying process, and finally realizes high-fidelity replication of the pattern, strong relief level, and clear and sharp edge.

[0048] 2. By combining specific gel system, high aspect ratio sheet-shaped powder and freezing shaping with segmented drying process, the internal stress of the powder block during dehydration and drying process is solved. The shrinkage deformation of the powder block is significantly inhibited, which has extremely low edge shrinkage rate and is not easy to crack, has high structural integrity and mechanical strength, and shows excellent impact resistance and structural stability in drop and centrifugal tests.

[0049] 3. The inverted pressure dehydration process enables the gel component to form firm "in-situ bonding points" between powder particles and the bottom support mesh, thereby achieving the integrated and firm combination of the powder block and the bottom support without relying on any additional adhesive. This avoids the safety risks of heavy metal residues that may be introduced by traditional adhesives, and greatly improves the skin feel of the final product, making it more skin-friendly, smooth and moisturizing.

[0050] 4. The specific design of the bottom support structure in this application can achieve more uniform and gradient pressure distribution during the inverted pressure dehydration process, ensuring consistent density and bonding force of the powder block from the center to the edge, effectively avoiding the problems of local insufficient compaction or excessive compression. This optimized pressure distribution, combined with the mesh structure, enables the gel component in the mixed fluid to be more fully embedded and anchored in different areas of the bottom support, thereby greatly enhancing the mechanical interlocking force and integrated bonding strength between the powder layer and the bottom support. BRIEF DESCRIPTION OF DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0052] Figure 1 For the overall back structure of the shell of the bottom support and the mold shell after being buckled together during the preparation of the three-dimensional powder block; Figure 2 For the front structure of the bottom support; Figure 3 For the structure of the mold shell; Figure 4 For the structure of the shell.

[0053] The bottom support (1); the center area (11); the first through hole (111); the middle area (12); the second through hole (121); the edge area (13); the stop edge (131); the mold shell (2); the trough (21); the shell (3); the accommodating groove (31). DETAILED DESCRIPTION

[0054] The application will be described in detail below with reference to the embodiments. The following embodiments will help the skilled in the art to further understand the application, but do not limit the application in any form. It should be noted that for those skilled in the art, several adjustments and improvements can be made without departing from the concept of the application. These are within the scope of protection of the application.

[0055] The application provides a base for preparing a three-dimensional powder block, a three-dimensional powder block and a preparation method thereof.

[0056] The application provides a base for preparing a three-dimensional powder block, which has the structure as shown in Figure 2 The base 1 comprises a central region 11, an intermediate region 12 and an edge region 13 connected in sequence, the intermediate region 12 is arranged in a circumferential direction around the central region 11, and the edge region 13 is arranged in a circumferential direction around the intermediate region 12; the central region 11 is provided with a plurality of first through holes 111 arranged at intervals, the intermediate region 12 is provided with a plurality of second through holes 121 arranged at intervals, and the plurality of first through holes 111 and the plurality of second through holes 121 jointly form a mesh structure; the mesh allows the mixed fluid of the powder block to enter to realize the integrated combination of the powder block and the base; so that the fixed powder after solidification is more reliable; the central region 11 and the intermediate region 12 are not in the same plane.

[0057] It should be noted that the central region 11 and the intermediate region 12 are not in the same plane, and when viewed from the front, the intermediate region 12 is higher than the central region 11, that is, according to the position viewed from the front Figure 2 The intermediate region 12 protrudes inwardly compared with the central region 11, and when the inverted pressure three-dimensional powder block is observed from the outside, the central region 11 protrudes outwardly more than the intermediate region 12.

[0058] The plurality of first through holes (111) and the plurality of second through holes (121) are centrally symmetrically distributed; the shape of each of the first through holes (111) and the second through holes (121) is a regular geometric shape (preferably a sector, a rectangle, a circle, an ellipse or a sector ring).

[0059] Further, the plurality of first through holes 111 are centrally symmetrically distributed and are all sector ring structures, and the plurality of second through holes 121 are centrally symmetrically distributed and are all circular; which enhances the seniority of the appearance.

[0060] The first through holes 111 can also be circular, polygonal, or irregularly shaped.

[0061] The second through holes 121 can be polygonal or irregularly shaped.

[0062] The outer side of the edge region 13 extends in a radial direction to form a retaining edge 131. The retaining edge 131 forms a ring structure, which matches the shape of the circumferential edge of the mold shell 2.

[0063] This design first optimizes the pressure distribution and improves the pressing uniformity. In the reverse pressure dewatering step, when the pressure is applied to the mixed fluid through the bottom support, this design effectively avoids the defect that the traditional flat bottom support may cause the pressure to concentrate in the center area and the pressure to be insufficient at the edge, ensuring that the compactness and structural strength of the powder block from the center to the edge are more uniform and consistent, laying a structural foundation for obtaining high-quality powder blocks with low edge shrinkage and no cracking.

[0064] Secondly, the mechanical interlocking is strengthened, and the bonding firmness is enhanced. The high-low difference structure combined with the mesh design provides more abundant anchoring nodes for the mixed fluid in three-dimensional space. Under the action of pressure, the fluid not only embeds into the plane mesh, but also fills into the three-dimensional space formed by the high-low difference. After dewatering and drying, a complex "three-dimensional embedded" structure is formed between the powder layer and the bottom support, which penetrates through different planes. This strong mechanical interlocking effect makes the integration of the powder block and the bottom support extremely firm, significantly improves the durability of the product, and ensures that the powder block can effectively resist impact and vibration during use and transportation, and is not easy to separate from the bottom support.

[0065] In actual application, the bottom support 1 can adopt various shapes, such as circular, rectangular, oval or square, polygon, etc. in plan view. The mold shell 2 is matched with the shape of the bottom support 1, so that the assembly is fast and convenient, and the firmness is good.

[0066] The bottom support is made of plastic injection molding or metal disc; the plastic is selected from one of polypropylene, ABS, polyethylene terephthalate. The metal can be aluminum, aluminum alloy, tinplate, stainless steel.

[0067] The center area 11, the middle area 12 and the edge area 13 can be an integral forming structure, and optionally, the middle area 12 is annular and arranged along the circumference of the center area 11, and the edge area 13 is annular and arranged along the circumference of the middle area 12.

[0068] In the present application, the synthetic fluorophlogopite is: Fujian Yanzhuang New Material Technology Co., Ltd., CS800; Mica (UNI-MICA 1250): United Micro Powder; HDI / trimethylol hexyl lactone cross-linked polymer: United Micro Powder; Color powder CI 73360: United Micro Powder; Color powder CI 77891: United Micro Powder; "Seawater" has been officially included in the "Catalogue of Cosmetics Raw Materials in Use (2021 Edition)".

[0069] Example 1 The embodiment provides a preparation method of a reverse pressure type high-fidelity three-dimensional powder block. The method can prepare the color cosmetic powder block with high surface fineness, good three-dimensional pattern fidelity, stable structure and no additional adhesive through specific material system and process flow.

[0070] The method comprises the following steps: S1, preparing a mixed fluid The mixed fluid formula is shown in Table 1 in terms of weight percentage: Table 1. Components and contents (weight percentage)

[0071] The preparation method comprises the following steps: S11, preparing powder A The base components (synthetic fluorphlogopite, mica, HDI / trimethylol hexyl lactone cross-linked polymer) are uniformly premixed; the color powder in the coloring phase is added, and is mixed in a powder mixing device at 1500 r / min for 4 times, with each mixing time being about 2 minutes, so that the color powder is uniformly dispersed; then the pearlescent powder is added, and is mixed at a low speed of 500 r / min for 2 times, with each mixing time being about 2 minutes, so that the pearlescent powder is prevented from being damaged, and the uniform powder A is obtained; S12, preparing water phase The deionized water, glycerol and gum thickener are mixed; heating is carried out in a 60-80 DEG C water bath, and stirring is carried out at 500-1000 r / min until the gum is completely dissolved, and a uniform gel is formed; after the seawater is configured into an aqueous solution, the seawater is added, and stirring is carried out until a thixotropic gel is formed. Then, the surfactant (coconut oil glutamic acid disodium) is added, and stirring and dispersion are uniformly carried out, so that the water phase is obtained.

[0072] S13, preparing oil phase The emulsifier and the emollient are mixed, heating and stirring are carried out at 60-70 DEG C until complete melting, and the oil phase is obtained.

[0073] S14, preparing water-oil continuous gel B The oil phase is slowly poured into the water phase, high-speed homogenization is carried out at 3000-5000 r / min for 3-5 minutes, a stable emulsion is formed, cooling is carried out to 40±5 DEG C, the preservative (phenoxyethanol) is added, and high-speed homogenization is carried out at 3000-5000 r / min for 3-5 minutes again, so that the water-oil continuous gel B is obtained.

[0074] S15, fluid preparation The powder A and the gel B are mixed, heating and stirring are carried out at 40-60 DEG C, and a flowable uniform fluid is formed.

[0075] S2, providing a combined mold As Figures 1 to 4As shown, a set of combined mold is provided, including the base support as described above, and a mold shell 2 made of flexible material and provided with a material groove 21 for containing powder, the size of the mold shell is matched with the size of the base support 1; the base support 1 is configured to be embedded in the opening of the material groove 21, and its height is set to be lower than the depth of the material groove 21, so that when the base support 1 is buckled to the mold shell 2, there is a gap between the base support 1 and the bottom of the material groove 21, which provides space for the redistribution and compaction of the mixed fluid under pressure. In this embodiment, the base support is circular and made of polypropylene; the mold shell is a circular silica gel shell.

[0076] As shown Figure 3 , Figure 4 As shown, since the mold shell 2 is made of silica gel material and has a certain flexibility, it is easy to deform when subjected to external pressure, and in this embodiment, a sleeve shell 3 is provided outside the mold shell 2; which can constrain the shape of the mold shell 2.

[0077] Specifically, the middle part of the sleeve shell 3 is configured with a containing groove 31 for containing the mold shell 2, in order to facilitate the containing groove 31 to exhaust air when assembling the mold shell 2, and to speed up the assembly, a through hole can be provided at the bottom of the sleeve shell 3.

[0078] S3, pouring and molding: pouring the fluid prepared in S1 into the material groove 21 of the mold shell 2, and then covering the base support 1 upside down on the surface of the fluid.

[0079] S4, inverted pressure dewatering By applying a vertical downward pressure to the mixed fluid through the base support 1, the water in the fluid is discharged through the mesh, and part of the fluid enters the mesh, realizing the preliminary combination of the powder block and the base support 1; in this embodiment, the applied pressure is 0.2MPa, and the pressure holding time is 2 seconds.

[0080] In this step, a water-absorbing material such as non-woven fabric or water-absorbing paper can be covered on the outer surface of the base support 1, i.e. the side facing away from the mixed fluid. Under the action of pressure, the fluid bears pressure stress. At this time, under the driving of the pressure gradient, the free water and part of the bound water in the fluid will move upward along a certain migration path W. The water passes through the mesh structure composed of the first through hole 111 and the second through hole 121 on the base support 1 in turn, and is quickly absorbed and transferred by the high-absorbent non-woven fabric layer close to the outer surface of the base support, thereby realizing rapid and directional preliminary dewatering and compaction.

[0081] In this step, since the pressure is directly applied to the base support which is finally combined with the powder block, the intervention of the film cloth is avoided, thereby fundamentally eliminating the problem of leaving film cloth texture on the surface of the powder block.

[0082] S6, Freeze-shaping The mold, which has been dehydrated by reverse pressure and the powder has been preliminarily combined with the base, is quickly transferred to a low-temperature freezer at -40°C to -45°C (in this embodiment, -45°C) for 12 minutes of rapid freezing treatment. This step aims to instantaneously freeze the remaining water in the powder block into fine ice crystals. These ice crystals form a solid three-dimensional framework between the powder particles, instantaneously "locking" the complex three-dimensional pattern and fine texture formed by the mixed fluid in the mold tank, and physically fixing the macroscopic and microscopic morphology of the powder block. This step is crucial for preventing pattern blurring, edge collapse, or macroscopic deformation caused by water evaporation and internal stress changes during subsequent drying, thus providing a key guarantee for achieving high-fidelity pattern replication.

[0083] S7, Subsection drying: The mold with the frozen powder block combined with the base is removed from the freezer, and the frozen powder block is detached from the base by utilizing the elasticity of the silicone shell. Then, the frozen powder block is placed in a freeze-drying device for subsection drying; S71, Low-temperature drying: The temperature is slowly increased from -45°C to 0°C at a rate of 7.5°C / hour, and the relative humidity is controlled at 40%. The powder block is subjected to 6 hours of low-temperature sublimation drying under these conditions.

[0084] Its main role is to slowly sublimate the ice crystals on the surface and shallow layer of the powder block through air flow, and remove part of the liquid water. This gentle process helps to slowly release the internal stress generated by freezing and preliminary dehydration, avoiding surface cracking caused by vigorous drying.

[0085] S72, Elevated-temperature drying: After low-temperature drying, the temperature is increased from 0°C to 40°C, and the air-drying is continued at this temperature for 6 hours.

[0086] Through the above steps, the final three-dimensional powder block product is obtained, denoted as Sample 1 (corresponding to Formula 1); Sample 2 (corresponding to Formula 2), Sample 3 (corresponding to Formula 3). The three-dimensional powder block product includes a layer of compacted and dried powder, and a base firmly combined with the powder layer through an "in-situ bonding" mechanism. The edges of the three-dimensional relief pattern are sharp, with distinct levels and high detail reproduction. The entire powder block has no visible cracks, and the edges are neat.

[0087] Example 2 This embodiment uses exactly the same composition formula as Formula 1 of Example 1, but the process parameters of the freeze-shaping step S6 and the subsection drying step S7 are adjusted.

[0088] Specifically, steps S1-S5 are the same as Example 1; In the execution of the freeze-forming step S6, the process parameters are adjusted as follows: the mold is subjected to a freeze treatment at a temperature of -30°C, and the freeze time is 15 minutes.

[0089] Next, in the execution of the segmented drying step S7, the parameters of both stages are adjusted.

[0090] S71 low-temperature drying, the temperature is slowly increased from -30°C to 0°C (heating rate 7.5°C / hour), and the relative humidity is controlled at 45%, under which conditions the powder block is subjected to low-temperature sublimation drying for 4 hours.

[0091] S72 in the temperature increase drying: after the low-temperature drying is completed, the temperature is increased from 0°C to 40°C, and the air blowing drying is continued at this temperature for 5 hours.

[0092] The rest of the operations, including the materials used, the mold, the equipment, etc., are consistent with Example 1, and Sample 4 is prepared.

[0093] The experimental results show that, using the adjusted process parameters in this example, the final three-dimensional powder block product (Sample 4) has no significant difference in macroscopic morphology and microscopic structure from the product of Example 1. The product also achieves high-fidelity three-dimensional patterns, smooth surfaces, and firm combination with the base support, without defects such as cracking and severe edge shrinkage.

[0094] Comparative Example 1 The difference between this comparative example and Example 1 is that the freeze-forming step S6 is omitted; after the reverse pressure dehydration, the segmented drying S7 is directly performed. Sample 5 is prepared.

[0095] Experimental results: the powder block product obtained has serious structural collapse and pattern distortion. The three-dimensional relief height in the center of the powder block is significantly reduced, the edge sharpness is lost, and the fine texture is blurred. During the drying process, it can be observed that the overall powder block shrinks and deforms. The internal structure of the powder block is loose, and it is highly fragile. This result proves that the freeze-forming step is crucial for "locking" the three-dimensional pattern and preventing deformation due to water migration and gravity during the initial drying period.

[0096] Comparative Example 2 The difference between this comparative example and Example 1 is that the center region 11 and the middle region 12 of the base support are arranged on the same plane, i.e., the original high-low difference structure is cancelled, and the rest of the preparation conditions and parameters are exactly the same as in Example 1, and Sample 6 is prepared.

[0097] Test results: compared with the sample obtained in Example 1, the flat bottom support structure cannot realize the gradient pressure guide of the original height difference design in the reverse pressure dewatering process, resulting in uneven distribution of the applied pressure, excessive compaction of the center area of the powder block, and insufficient compaction of the edge area. In the subsequent drying stage, micro-cracks are generated in the center area; and the overflowed material body has no directional turbulent flow, which is easy to be contaminated.

[0098] In addition, after the height difference is cancelled, the combination between the powder layer and the bottom support is "two-dimensional plane fitting"; which leads to a significant decrease in the bonding force between the powder block and the bottom support; and the powder block is easy to be detached from the bottom support.

[0099] Performance test drop test The powder blocks prepared from the formulations 1-3 of Example 1, the powder block of Example 2, and the powder blocks of Comparative Examples 1-2 were tested according to the drop test in the standard QB / T 1976-2004 "Cosmetic Powder Block"; and the results are shown in Table 2.

[0100] Table 2

[0101] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. The present application can have various modifications and changes for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A base for the preparation of a stereoscopic block, characterized in that, The base support (1) comprises a center area (11), an intermediate area (12) and an edge area (13) connected in sequence, the intermediate area (12) is arranged around the circumference of the center area (11), and the edge area (13) is arranged around the circumference of the intermediate area (12); the center area (11) is provided with a plurality of first through holes (111) arranged at intervals, the intermediate area (12) is provided with a plurality of second through holes (121) arranged at intervals, and the plurality of first through holes (111) and the plurality of second through holes (121) jointly form a mesh structure; the mesh allows the mixed fluid of the powder block to enter to realize the integrated combination of the powder block and the base support; the center area (11) and the intermediate area (12) are not in the same plane.

2. The frame of claim 1 wherein, The plurality of first through holes (111) and the plurality of second through holes (121) are centrally symmetrically distributed; the shape of each first through hole (111) and second through hole (121) is a regular geometric shape.

3. The frame of claim 1 wherein, The outer side of the edge area (13) extends in the radial direction to form a baffle (131).

4. The frame of claim 1 wherein, The intermediate area (12) is higher than the center area (11).

5. A method of preparing a reverse pressure high fidelity stereocake, characterized in that, The method comprises the following steps: S1, preparing a mixed fluid: preparing a mixed fluid containing a powder component and a water-oil continuous gel, wherein the powder component contains a base and a coloring phase, and the water-oil continuous gel contains a water phase and an oil phase; S2, providing a combined mold: providing a set of combined molds, which comprises a mold shell (2) made of flexible material and provided with a material groove (21), and a base support (1) as claimed in any one of claims 1-4 matched in size with the mold shell; the base support (1) is configured to be embedded in the opening of the material groove (21), and its height is set to be lower than the depth of the material groove (21), so that when the base support (1) is buckled on the mold shell (2), there is a gap between the base support (1) and the bottom of the material groove (21), providing space for the redistribution and compaction of the mixed fluid under pressure; S3, pouring and combining: pouring the mixed fluid into the material groove (21) of the mold shell (2), and then covering the surface of the mixed fluid with the base support (1) upside down; S4, reverse pressure dewatering: applying pressure to the mixed fluid through the base support (1) to make the water in the fluid discharge through the mesh structure formed by the first through holes (111) and the second through holes (121) of the base support (1), while part of the fluid enters the mesh structure, realizing the preliminary combination of the powder block and the base support (1); S5, freeze setting and demolding: freeze setting the entire mold after reverse pressure dewatering, and then using the flexibility of the mold shell (2) to demold the frozen powder block that has been preliminarily combined with the base support (1) from the material groove (21); S6, drying the powder block after freeze setting to obtain the powder block.

6. The method of claim 5, wherein the inverted pressure high fidelity stereo block is prepared by, In S1, the components of the mixed fluid include, by weight percentage: Base: 50-65%; Coloring phase: 1-10%; Water phase: 5-25%; Oil phase: 5-10%; Preservative: 0.1-1.0%; Solvent: make up to 100%.

7. The method of claim 5, wherein the inverted pressure high fidelity stereo block is prepared by, The components of the mixed fluid include, by weight percentage: 。 8. The method of claim 5, wherein the inverted pressure high fidelity stereo block is prepared by, In step S1, the mixed fluid is prepared by a method comprising the following steps: S11, preparing powder A: after mixing the base components uniformly, add the toner in the coloring phase, and perform high-speed mixing and dispersion; then add the pearl powder, and perform low-speed mixing to obtain uniform powder A; S12, preparing the water phase: mix deionized water, humectants, and gum thickener, heat and stir until the gum is completely dissolved to form a uniform gel; then add an aqueous solution of inorganic salt ion source, stir until a thixotropic gel is formed; then add the surfactant, stir and disperse uniformly to obtain the water phase; S13, preparing the oil phase: mix the emulsifier and emollient, heat and stir until completely melted to obtain the oil phase; S14, preparing the water-oil continuous gel B: pour the oil phase into the water phase, perform high-speed homogenization to form a stable emulsion; after cooling, add the preservative, perform high-speed homogenization again to obtain the water-oil continuous gel B; S15, fluid preparation: mix the powder A with the water-oil continuous gel B, stir under heating conditions to form a flowable and uniform mixed fluid.

9. The method of claim 5, wherein the inverted pressure high fidelity stereo block is prepared by, In step S5, the temperature of the freeze-forming treatment is -40°C to -65°C, and the time of the freeze-forming treatment is 10 minutes to 15 minutes; And / or, in step S6, the drying treatment is a segmented drying treatment, which includes a low-temperature drying stage and a temperature-increasing drying stage.

10. The three-dimensional block prepared by the preparation method of any one of claims 5-9.

Images