Micron-sized pearl glaze ceramic and preparation method thereof

Abstract

The invention discloses micron-sized pearl glaze ceramic and a preparation method thereof, and relates to the technical field of ceramic, and the micron-sized pearl glaze ceramic is characterized by comprising a ceramic body, a toning ground coat layer and a dry particle layer, the toning ground coat layer is prepared from the following raw materials in parts by weight: 15 to 25 parts of quartz, 20 to 30 parts of feldspar, 5 to 10 parts of kaolin, 3 to 8 parts of calcined zinc oxide, 5 to 10 parts of calcium carbonate, 8 to 15 parts of barium carbonate, 8 to 15 parts of zirconium silicate, 0.05 to 0.5 part of toning metal oxide and 1 to 3 parts of functional additive; the dry particle layer is prepared from the following raw materials in parts by weight: 30 to 40 parts of quartz sand, 10 to 15 parts of borax, 5 to 8 parts of sodium carbonate, 3 to 6 parts of lithium carbonate, 10 to 18 parts of Bi2O3, 10 to 18 parts of TiO2, 0.5 to 2 parts of rare earth oxide and 0.5 to 2 parts of nucleating agent. The prepared ceramic shows soft and layered pearl luster under light rays of different angles, and the physical performance is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of ceramic tile preparation technology, and in particular to a micron-sized pearl glaze ceramic and its preparation method. Background Technology

[0002] In the field of architectural ceramics, the decorative effect and physicochemical properties of glazes are key factors determining product quality and market competitiveness. With the continuous upgrading of high-end architectural decoration demands, the market has placed higher requirements on the decorative texture (such as a delicate pearly luster) and practical performance (high hardness, weather resistance, acid and alkali resistance, etc.) of ceramic glazes. Traditional pearl glaze preparation techniques often employ the addition of pearlizing agents to a single layer of glaze or the application of dry granules, which has many limitations: In terms of decorative effect, the pearly luster is singular, making it difficult to achieve a coordinated "base color-gloss" effect on tiles. Furthermore, the limited means of microstructure control prevent the formation of a uniform, delicate micron-level pearly texture, resulting in a thin visual hierarchy. In terms of performance, traditional systems struggle to balance high gloss with high hardness and wear resistance, leading to insufficient acid and alkali resistance and poor stain resistance in pearl glaze tiles, limiting their application in demanding environments.

[0003] It is evident that existing technologies still need improvement and enhancement. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a micron-level pearl glaze ceramic and its preparation method, aiming to solve the problems that traditional single-layer glazes cannot form a uniform and delicate micron-level pearl texture; and that the physicochemical properties such as glaze hardness, wear resistance, and acid and alkali resistance are difficult to meet the high requirements of high-end architectural decoration.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A micron-sized pearl glaze ceramic comprises a ceramic body, a color-tuning base glaze layer, and a dry granule layer. The raw materials of the color-tuning base glaze layer, by weight, include: 15-25 parts quartz, 20-30 parts feldspar, 5-10 parts kaolin, 3-8 parts calcined zinc oxide, 5-10 parts calcium carbonate, 8-15 parts barium carbonate, 8-15 parts zirconium silicate, 0.05-0.5 parts color-tuning metal oxide, and 1-3 parts functional additives. The raw materials of the dry granule layer, by weight, include: 30-40 parts quartz sand, 10-15 parts borax, 5-8 parts sodium carbonate, 3-6 parts lithium carbonate, 10-18 parts Bi₂O₃, 10-18 parts TiO₂, 0.5-2 parts rare earth oxides, and 0.5-2 parts nucleating agent.

[0007] The micron-sized pearl glaze ceramic, wherein the feldspar is one or both of potassium feldspar and sodium feldspar; and the coloring metal oxide is one or more of Fe2O3, Cr2O3 and Co3O4.

[0008] The micron-sized pearl glaze ceramic, wherein the functional additive is one or more of bentonite, sodium carboxymethyl cellulose, MgO and SrO.

[0009] The micron-sized pearl glaze ceramic, wherein the rare earth oxide is one or both of CeO2 and Er2O3; and the nucleating agent is P2O5.

[0010] A method for preparing micron-sized pearl glaze ceramic as described in this invention, comprising the steps of:

[0011] Weigh the raw materials for the color-matching base glaze according to the formula ratio, then add deionized water and dispersant sodium tripolyphosphate, and then sieve the mixture after wet ball milling to obtain the base glaze slurry.

[0012] Weigh the raw materials of the dry granule layer according to the formula ratio, sieve them, and then dry ball mill them until uniform to obtain dry granule mixed powder. Melt the dry granule mixed powder and quench it in water to form glass fragments. After drying, crush it and grade it to obtain surface reaction dry granules.

[0013] A base glaze slurry is evenly applied to the surface of the ceramic body using a spray glazing method, and after drying, a colored base glaze layer is formed.

[0014] The surface reaction dry granules are mixed with a suspending agent and evenly coated onto the surface of the dry tinted base glaze layer using a bell jar glazing method. After drying, a dry granule layer is formed.

[0015] Micron-sized pearl glaze ceramics are obtained by sintering ceramic bodies that form a tinted base glaze layer and a dry granule layer under an oxygen atmosphere.

[0016] The method for preparing the micron-sized pearl glaze ceramic includes the following step: wet ball milling followed by sieving to obtain the base glaze slurry. This includes: wet ball milling with a material:ball:water ratio of 1:2:0.6-0.8 for 6-12 hours until the fineness is ≤0.1%; passing the slurry through a 250-mesh sieve; and adjusting the slurry specific gravity to 1.50-1.55 g / cm³. 3 After aging for 20-30 hours, a base glaze slurry is obtained.

[0017] In the preparation method of the micron-sized pearl glaze ceramic, the melting temperature of the dry granule mixed powder is 1250-1350℃ and the melting time is 1-2 hours.

[0018] The method for preparing micron-sized pearl glaze ceramics includes a step of sintering the ceramic body forming the tinted base glaze layer and the dry granule layer under an oxygen atmosphere, comprising a heating stage, a holding stage, and a cooling stage. In the heating stage, the temperature is increased to 1200-1260℃ at a heating rate of 30-40℃ / min; in the holding stage, the temperature is held at 1200-1260℃ for 5-10 min; in the cooling stage, the temperature is first rapidly cooled to 750-850℃ at a cooling rate of 100-130℃ / min, then cooled to 450-550℃ at a cooling rate of 20-40℃ / min, and then cooled to room temperature in the furnace.

[0019] Beneficial effects: This invention adopts a two-layer structure of "functional color-tuning base glaze + surface reactive dry granules". The color-tuning base glaze layer provides main colors such as off-white and light gray. The microcrystalline phase generated by the reaction of the dry granules and the base glaze forms a uniform and delicate micron-level "nacre" structure, realizing the linkage between "base color and luster". It shows a soft and layered pearl luster under different angles of light, and the visual effect is far superior to traditional single-layer glazes. Moreover, by controlling the particle size and distribution of the dry granules, this invention can also ensure that the pearl effect is delicate and smooth, without obvious graininess, and enhance the high-end texture of the product.

[0020] The reactive dry granules in the dry granule layer of this invention are rich in high-hardness components and react with the base glaze to form a dense structure. The glaze has a high Mohs hardness and better wear resistance than traditional porcelain glazes. The high proportion of raw materials such as barium carbonate forms a dense glass phase. Combined with the optimized firing process, the glaze has excellent resistance to acid and alkali corrosion and strong stain resistance. This invention ensures good matching between the base glaze and the body, and between the dry granule reaction layer and the base glaze by controlling the thermal expansion coefficient of each layer. It has excellent thermal shock resistance and no defects such as glaze cracking or glaze shrinkage. Attached Figure Description

[0021] Figure 1 This is a flowchart of a method for preparing micron-sized pearl glaze ceramics according to the present invention.

[0022] Figure 2 This is a photograph of the micron-sized pearl glaze ceramic prepared in Example 1 of the present invention.

[0023] Figure 3 This is a photograph of the micron-sized pearl glaze ceramic prepared in Example 2 of the present invention.

[0024] Figure 4 This is a photograph of the micron-sized pearl glaze ceramic prepared in Example 3 of the present invention. Detailed Implementation

[0025] This invention provides a micron-sized pearl glaze ceramic and its preparation method. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the following embodiments are provided to further illustrate the invention in detail. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0026] This invention provides a micron-sized pearl glaze ceramic, comprising a ceramic body, a color-tuning base glaze layer, and a dry granule layer. The raw materials of the color-tuning base glaze layer, by weight, include: 15-25 parts quartz, 20-30 parts feldspar, 5-10 parts kaolin, 3-8 parts calcined zinc oxide, 5-10 parts calcium carbonate, 8-15 parts barium carbonate, 8-15 parts zirconium silicate, 0.05-0.5 parts color-tuning metal oxide, and 1-3 parts functional additives. The raw materials of the dry granule layer, by weight, include: 30-40 parts quartz sand, 10-15 parts borax, 5-8 parts sodium carbonate, 3-6 parts lithium carbonate, 10-18 parts Bi₂O₃, 10-18 parts TiO₂, 0.5-2 parts rare earth oxides, and 0.5-2 parts nucleating agent.

[0027] This invention employs a two-layer structure of "functional color-tuning base glaze + surface reactive dry granules." The color-tuning base glaze layer provides main tones such as off-white and light gray. The microcrystalline phase generated by the reaction between the dry granules and the base glaze forms a uniform and delicate micron-level "nacre" structure, achieving a linkage between "base color and luster." Under different angles of light, it displays a soft and layered pearly luster, with a visual effect far superior to traditional single-layer glazes. Specifically, the raw materials in the dry granule layer are the "initial units" for forming the "nacre" structure. The dry granule layer formula is based on the Bi2O3-TiO2 system, and these two oxides are the "raw material library" for generating the key microcrystalline phase (Bi2Ti2O7) for pearly luster. Bi2O3, as a high refractive index component (refractive index ≈ 2.4), and TiO, as the "skeleton" for crystal phase formation, undergo a solid-state reaction during firing to directionally generate Bi2Ti2O7 microcrystals. These microcrystals have a layered structure and extremely strong ability to scatter and interfere with light, serving as the "optical core" of the pearly luster. Simultaneously, rare earth oxides such as CeO2 and / or Er2O3 are added to the dry granule layer. On the one hand, this refines the grains (inhibiting excessive growth of BiTiO grains) and improves uniformity; on the other hand, their high whiteness enhances light reflection efficiency. P2O5, as a nucleating agent, forms a large number of uniform nucleation points at the interface between the dry granules and the base glaze, guiding the BiTiO microcrystals to nucleate densely and grow uniformly at the interface, avoiding localized coarse grains or uneven distribution.

[0028] In this invention, the "pearl" structure is not formed solely by the dry particles, but rather as a composite structure formed during firing through "partial melting-ion diffusion-synergistic crystallization" between the dry particles and the tinted base glaze layer. The "reaction compatibility" of the tinted base glaze layer is crucial for uniformity. The functional tinted base glaze does not passively support the dry particles but rather acts as a "reaction medium" through compositional design. Calcined zinc oxide, MgO, and other functional additives are added to the tinted base glaze layer to reduce viscosity at high temperatures (but not excessively, to avoid complete dissolution of the dry particles), allowing the edges of the dry particles to melt moderately and form a "semi-fused interface" with the base glaze. This ensures both the Bi... 3+ 、Ti4+ Plasma diffuses from the dry granule layer to the tinted base glaze layer, while preventing the dry granules from completely "disappearing" in the tinted base glaze layer, thus preserving a "local high concentration area" for the formation of microcrystalline phase. Zirconium silicate in the tinted base glaze layer acts as an opacifier, forming a uniform basic opacified structure, avoiding "color difference through the body" caused by the light transmission of the base glaze. At the same time, its uniformly distributed particles can act as a "dispersant," indirectly inhibiting the excessive aggregation of microcrystalline phase after the reaction of dry granules.

[0029] In this invention, the optical effect of "nacre" is not a single reflection, but the combined effect of "light scattering of the microcrystalline phase + light interference of the interface", and it presents a "soft dynamic feeling" with the change of viewing angle. Among them, the "light scattering" of the micron-sized microcrystals forms a delicate luster. The BiTiO (refractive index ≈ 2.4) densely distributed in the nacre structure has a significant refractive index difference with the surrounding glass phase (refractive index ≈ 1.5). When light shines on it, the microcrystalline particles will produce "multiple diffuse reflections" of the light. Unlike specular highlights (reflection in one direction) or matte (strong absorption), this scattering makes the light form a soft "glossy feeling" at different angles. Moreover, because the size of the microcrystals (1-5μm) is much smaller than the resolution of the naked eye (about 50μm), it appears "fine and particle-free" on a macroscopic level.

[0030] The "light interference" of the interface enhances the sense of layering. There are multiple interfaces of "glass phase-microcrystalline phase-glass phase" in the transition area between the dry granule layer and the tinted base glaze layer. Different interfaces will interfere with the reflected light: when the wavelength of light matches the interface spacing, the light of a specific wavelength is enhanced (such as blue light and green light), so that the pearl luster presents a slight "iridescent effect" (rather than a monotonous luster) at different angles. When superimposed with the base color of the base glaze, it forms a linkage effect of "stable base color + dynamic luster" (such as off-white base color + pearl luster presents a warm and soft feeling, light gray base color + pearl luster presents a cool and high-end feeling).

[0031] In this invention, the base color (base glaze) and the luster (pearl structure) are not simply superimposed, but rather "complementarily enhanced." The uniform base color of the tinted base glaze layer avoids the "cheap" feeling caused by a cluttered background (such as the mottled appearance of traditional dry granules due to uneven base color); the dynamic feel of the pearl luster adds "visual layers" to a single base color (for example, a matte off-white base glaze would appear monotonous, while the addition of pearl luster creates a rich texture due to differences in light reflection). The two achieve functional separation through "layered design" (the base color is handled by the base glaze, and the luster by the dry granule reaction layer), and form a linkage through optical superposition, satisfying the flexible decorative needs of "the same base color can present different luster intensities, and the same luster can be adapted to different base colors."

[0032] The improvement in physical properties such as hardness, wear resistance, and acid and alkali resistance of the micron-sized pearl glaze ceramic proposed in this invention is essentially the result of "microstructural densification + high stability of the composition itself + enhanced interfacial bonding", specifically stemming from the following mechanisms:

[0033] The BiTiO microcrystalline phase generated by the dry particle reaction has high hardness (Mohs hardness ≈ 6.5-7) and is densely distributed on the surface of the glaze (0.05-0.1 mm depth), which is equivalent to forming a "hard protective layer" on the glaze surface. At the same time, the unreacted high-purity quartz sand (SiO2) particles (residual part) in the dry particles and the zirconium silicate particles (Mohs hardness ≈ 7.5) in the base glaze form a "composite skeleton", which further improves the scratch resistance of the surface. During the firing process, the interfacial reaction between the dry particle layer and the color base glaze layer not only generates microcrystalline phase, but also reduces defects in the following ways: the flux such as calcined zinc oxide and MgO in the color base glaze layer works synergistically with Bi2O3 in the dry particles to reduce the surface tension during melting, so that the glaze surface has good leveling properties at high temperature and reduces defects such as pinholes and bubbles (porosity <1%).

[0034] The high proportion of barium carbonate in the glass phase forms Ba-O bonds, which has a much higher chemical stability than traditional alkali metal oxides such as Na2O and K2O (the latter are prone to react with acids), thus improving acid resistance. The BiTiO microcrystalline phase is not easily dissolved in acidic or alkaline environments, avoiding the "loss of gloss" or "peeling" of traditional glazes caused by corrosion of the glass phase.

[0035] In some embodiments, the feldspar is one or both of potassium feldspar and sodium feldspar; the coloring metal oxide is one or more of Fe2O3, Cr2O3 and Co3O4, but is not limited thereto.

[0036] In some embodiments, the functional additive is one or more of bentonite, sodium carboxymethyl cellulose, MgO and SrO, but is not limited thereto.

[0037] In some embodiments, the rare earth oxide is one or both of CeO2 and Er2O3; the nucleating agent is P2O5.

[0038] In some embodiments, a method for preparing micron-sized pearl glaze ceramics as described in this invention is also provided, such as... Figure 1 As shown, it includes the following steps:

[0039] S10. Weigh the raw materials for the color-adjusting base glaze according to the formula ratio, then add deionized water and dispersant sodium tripolyphosphate, and sieve after wet ball milling to obtain the base glaze slurry.

[0040] S20. Weigh the raw materials of the dry granule layer according to the formula ratio, sieve them, and then dry ball mill them until uniform to obtain dry granule mixed powder. Melt the dry granule mixed powder and quench it in water to form glass fragments. Dry it, crush it, grade it, and sieve it to obtain surface reaction dry granules.

[0041] S30. Apply a base glaze slurry evenly to the surface of the ceramic body by spraying glaze, and form a colored base glaze layer after drying.

[0042] S40. Mix the surface reaction dry granules with the suspending agent, and evenly apply the mixture to the surface of the dry tinted base glaze layer using a bell jar glazing method. After drying, a dry granule layer is formed.

[0043] S50. The ceramic body forming the tinted base glaze layer and the dry granule layer is sintered in an oxygen atmosphere to obtain micron-sized pearl glaze ceramic.

[0044] Specifically, the sintering process of the ceramic body forming the tinted base glaze layer and the dry granule layer under an oxygen atmosphere in this invention includes a heating stage, a holding stage, and a cooling stage. In the heating stage, the temperature is raised to 1200-1260°C at a heating rate of 30-40°C / min; in the holding stage, the temperature is held at 1200-1260°C for 5-10 minutes; in the cooling stage, the temperature is first rapidly cooled to 750-850°C at a cooling rate of 100-130°C / min, then cooled to 450-550°C at a cooling rate of 20-40°C / min, and then cooled to room temperature in the furnace.

[0045] The heating stage of this invention involves the ceramic body, the tinted base glaze layer, and the dry granule layer gradually reaching the reaction temperature from room temperature. The core requirement is to balance heating efficiency and thermal stress, ensuring that the decomposition and initial melting of raw materials proceed in an orderly manner. The design rate of 30-40℃ / min precisely meets this requirement: there are slight differences in the coefficient of thermal expansion (CTE) between the ceramic body (such as stoneware or porcelain), the base glaze, and the dry granules. If the heating rate is too fast (e.g., >40℃ / min), the interior and surface of the body, the interface between the base glaze and the body, and the interface between the dry granules and the base glaze will generate instantaneous thermal stress due to the large temperature gradient (the interior is cold and the surface is hot, resulting in surface tension), which may directly cause cracking of the body or micro-cracks in the glaze layer. If the heating rate is too slow (e.g., <30℃ / min), although thermal stress can be reduced, the firing cycle will be prolonged (reducing production efficiency), and the decomposition time of raw materials in the early low-temperature stage (e.g., 400-800℃) may be too long, which may increase the risk of gas residue. A rate of 30-40℃ / min strikes a balance between safety and efficiency, ensuring that the target temperature is reached within a reasonable time (approximately 30-40 minutes) to match the overall firing cycle, while also controlling the temperature gradient within the material's tolerance range to prevent cracking.

[0046] During the heating process, the raw materials (such as carbonates and organic impurities) in the body and base glaze will undergo decomposition reactions and release gases (such as CaCO3→CaO+CO2↑, kaolin dehydration, etc.). These gases need to be released before the glaze layer is completely melted and sealed, otherwise they will be trapped in the glaze layer and form pinholes or bubbles. A heating rate of 30-40℃ / min can match the critical temperature range for gas release. This rate will not cause "decomposition gases to be sealed by the molten glaze layer before being released in time" due to excessively slow heating, nor will it cause "decomposition reaction to enter the high temperature stage before it is complete" due to excessively fast heating, thus reducing bubbles and pinhole defects from the source.

[0047] The heat preservation stage is crucial for the "core reaction" (ion diffusion, crystal phase formation, and glaze leveling) between the dry granules and the base glaze. A temperature range of 1200-1260℃ and a duration of 5-10 minutes are key to achieving a balance between "sufficient reaction and structural stability." The formation of the pearlescent core crystal phase (such as BiTiO) in the dry granules and base glaze depends on "ion diffusion + solid-phase reaction" at high temperatures: Bi in the dry granules... 3+ 、Ti 4+ It needs to diffuse from the dry particles to the surface of the base glaze, and interact with the O in the base glaze. 2- BiTiO microcrystals are formed through bonding; simultaneously, rare earth elements (such as CeO) need to be uniformly dispersed in the glass phase to whiten and refine the grains. If the holding temperature is below 1200℃, the ion diffusion rate is slow (the diffusion coefficient increases exponentially with increasing temperature), and Bi... 3+ 、Ti 4+ It cannot fully diffuse to the interface layer, resulting in a small amount of crystalline phase formation and uneven distribution, weak pearly luster, and poor fineness; if the holding temperature exceeds 1260℃, the dry particles will completely melt (rather than "partially melt"), Bi 3+ 、Ti 4+ Excessive diffusion into the base glaze (too low concentration) fails to form a "locally high-concentration microcrystalline zone" sufficient to produce a pearly luster. Even the already formed BiTiO microcrystals may redissolve due to excessively high temperatures, resulting in the loss of the pearl effect. 1200-1260℃ is the golden range for both "reactivity" and "structural stability," at which point the dry particles are in a "partially molten" state (the core retains its particle shape, while the edges soften). 3+ 、Ti 4+A moderate diffusion rate is crucial, ensuring sufficient microcrystalline phase formation without excessive diffusion leading to insufficient concentration. A holding time of 5-10 minutes guarantees the integrity of diffusion and reaction. If the holding time is less than 5 minutes, ion diffusion is incomplete, resulting in insufficient crystalline phase formation, a dull pearly luster, and incomplete leveling of the base glaze (the surface may retain minor unevenness). If the holding time is greater than 10 minutes, while the reaction is sufficient, prolonged high temperatures can cause excessive microcrystalline phase growth (grains growing from micrometers to sub-millimeters), potentially altering the pearly luster from "fine" to "rough" (with noticeable graininess). Furthermore, prolonged melting of the base glaze may cause "glaze flow" (thickening at the edges and thinning in the center), affecting smoothness. A holding time of 5-10 minutes ensures sufficient crystalline phase formation (density reaching 10⁻¹⁰ crystalline particles / mm²). 2 The grain size is uniform (1-3μm), and the base glaze is fully leveled (surface roughness Ra<0.1μm), ultimately presenting a delicate and uniform pearly luster.

[0048] The base glaze and dry granules are in a molten or semi-molten state (with fluidity) at high temperatures. The sustained high temperature during the heat preservation stage allows the glaze to achieve leveling through surface tension: the molten glaze spontaneously fills the tiny pits on the surface (such as the dents left by the bursting of tiny air bubbles during glazing), making the glaze smoother; at the same time, because the dry granules are partially melted, the edges change from "angular" to "rounded," preventing the edges of unleveled dry granules from forming "protrusions" (affecting the feel and gloss). At 1200-1260℃, the high-temperature viscosity of the base glaze is in a state of "easy to level but not flowable." If the temperature is insufficient, the viscosity is too high and cannot level; if the temperature is too high, the viscosity is too low and it will flow and deform. A heat preservation time of 5-10 minutes allows the glaze to complete leveling (experiments show that 6-8 minutes is enough to fill more than 90% of the tiny defects), resulting in a smooth and delicate glaze surface without surface defects such as "orange peel texture" or "pinholes."

[0049] The cooling stage is the process of "solidifying and shaping" the material from a high temperature state. The core requirements are to fix the beneficial structure (such as the distribution of microcrystalline phase), release internal stress, and avoid defects caused by cooling too fast or too slow. The segmented cooling design is precisely to control the material properties (such as glass phase transition and brittleness change) in different temperature ranges.

[0050] The first stage: Rapid cooling at 100-130℃ / min to 750-850℃ has the advantage of fixing the microcrystalline phase structure and improving gloss. 750-850℃ is the critical transition range for the glaze layer from the "molten state to the glassy state" (near the glass transition temperature Tg). Rapid cooling before this stage can quickly freeze the microstructure at high temperatures. If the BiTiO microcrystalline phase formed at high temperatures is cooled slowly during the cooling process, it may result in uneven distribution due to "Ostwald ripening" (dissolution of small grains and growth of large grains). Rapid cooling above 100℃ / min can quickly lower the temperature below Tg (the glaze layer changes from plastic to rigid), preventing the microcrystalline phase from "growing or aggregating," maintaining the uniform distribution formed during the holding stage (dense distribution of 1-3μm grains), ensuring the fineness of the pearly luster. The gloss of the glaze layer is directly related to the "transparency" of the glassy phase. If slowly cooled to 750-850℃, the glass phase may produce tiny opaque particles due to "phase separation," resulting in a decrease in gloss. Rapid cooling can avoid phase separation, keeping the glass phase uniform and transparent. The microcrystalline phase of the dry particle reaction layer can reflect and interfere with light more efficiently, increasing gloss by 10%-15% (compared to slow cooling). If slowly cooled in the high-temperature range of >850℃, the glaze layer may undergo slight deformation (such as edge sagging) due to being in a plastic state for a long time and being subjected to gravity. Rapid cooling can quickly remove it from the high-temperature plastic zone, avoiding deformation.

[0051] The second stage: Slow cooling to 450-550℃ at a rate of 30-50℃ / min has the advantage of releasing thermal stress and preventing glaze cracking. 450-550℃ is the transition range from a "rigid glassy state" to a "stable state at room temperature." At this point, the glaze layer is relatively brittle (high elastic modulus). If cooling is too rapid (e.g., 50℃ / min), the temperature difference between the interior and surface will generate thermal stress of "tensile stress on the surface and compressive stress on the interior" (stress increases by approximately 50MPa for every 100℃ increase in temperature difference). If this stress exceeds the tensile strength of the glaze layer (approximately 80-100MPa), glaze cracking will occur. If cooling is too slow (e.g., 20℃ / min), it will prolong the firing cycle and reduce production efficiency. A slow cooling rate of 30-40℃ / min allows the internal temperature gradient of the glaze layer to be controlled at 20-30℃ (temperature difference between surface and interior < 50℃), with thermal stress < 60MPa (below tensile strength), achieving "gradual stress release." From 750-850℃ to 450-550℃, the residual stress in the glaze layer (such as the stress generated by thermal expansion during the heat preservation stage) slowly relaxes as the temperature decreases, avoiding stress concentration; at the same time, the interfacial stress generated by the difference in CTE between the base glaze and the dry granule reaction layer (although they are matched, there are still slight differences) can be released during slow cooling through the slight plastic deformation of the glaze layer (there is still slight plasticity at 450-550℃), avoiding interfacial peeling.

[0052] The benefit of the final third stage of furnace cooling to room temperature is that it completely eliminates residual stress and ensures dimensional stability.

[0053] The sintering process of this invention achieves three precise matches through a complete process design of "heating rate control → heat preservation reaction control → cooling structure control": matching the heating rate with the material's thermal stress and raw material decomposition rhythm to reduce early defects; matching the heat preservation temperature and time with the requirements of crystal phase formation and glaze leveling to ensure decorative effect; and matching the segmented cooling with the material's glass transition and stress release law to ensure structural stability. Ultimately, through this process, ceramic tiles can not only form a uniform and delicate micron-level "nacre" structure, achieving a decorative effect that links "base color" and "gloss," but also improve physical properties such as hardness, wear resistance, and acid and alkali resistance by reducing defects such as bubbles, pinholes, and glaze cracks, while balancing production efficiency and product stability, making it suitable for industrial mass production.

[0054] In some embodiments, during the preparation of the base glaze slurry, the raw materials for the color-tuning base glaze layer are weighed according to the formula ratio, then deionized water and dispersant sodium tripolyphosphate are added. Wet ball milling is then performed with a material:ball:water ratio of 1:2:0.6-0.8 for 6-12 hours until the fineness is ≤0.1%. After milling, the slurry is passed through a 250-mesh sieve, and the specific gravity is adjusted to 1.50-1.55 g / cm³. 3 The mixture is aged for 20-30 hours to obtain the base glaze slurry. In this embodiment, the ball milling time of the base glaze slurry is controlled at 6-12 hours until the fineness is ≤0.1% (10,000-mesh sieve), which allows the raw materials to be fully ground, ensuring the fineness of the glaze slurry and providing a foundation for the glaze surface performance; the specific gravity of the slurry is maintained at 1.50-1.55 g / cm³. 3 A viscosity of 15-16 seconds ensures that the base glaze adheres evenly to the body during application, guaranteeing the thickness and smoothness of the glaze layer. The thickness of the tinted base glaze layer is 0.2-0.3mm, which affects the color depth of the base glaze and also relates to the bonding effect with dry particles and the smoothness of the glaze surface.

[0055] In some embodiments, the melting step of the dry granular mixture is carried out at a melting temperature of 1250-1350°C for 1-2 hours, but is not limited thereto.

[0056] In some embodiments, the particle size of the surface reactive dry particles is 20-40 μm, and the dispersion amount is 100-300 g / m³. 2 However, this is not the only factor. The particle size of the surface-reacting dry granules is crucial to the fineness and melting uniformity of the pearl effect. This particle size range allows the dry granules to form a suitable "nacreous" structure during firing; the dry granule distribution should be 100-300 g / m³. 2 The amount of pearl layer distributed determines the thickness, coverage, and intensity of the effect; different amounts of pearl layer distribution can produce different pearl luster effects.

[0057] The present invention will be further explained and illustrated below through specific embodiments:

[0058] The following experimental steps were used to test the performance of the ceramics prepared in the examples and comparative examples. The tested performance included: appearance: glaze gloss, pearl effect (uniformity, fineness, iridescence), color, flatness, and presence or absence of defects (pinholes, bubbles, glaze shrinkage, color difference, uneven melting of dry particles, etc.); physical properties: glaze hardness, wear resistance, acid and alkali corrosion resistance, and thermal shock resistance.

[0059] The gloss of the glaze is determined according to GB / T 13891-2008 "Method for Determination of Specular Gloss of Building Facing Materials". The testing tool is a gloss meter (such as a 60° angle gloss meter, suitable for high-gloss glazes). The testing steps are as follows: 1) Calibrate the instrument: Use standard plates (high gloss, medium gloss, low gloss) to calibrate the gloss meter and ensure that the error is ≤1 gloss unit; 2) Sampling: Cut a test piece from the tile to be tested and ensure that there are no obvious defects on the test surface (such as edge damage); 3) Measurement: Select 5 test points evenly on the surface of the test piece (1 point in the center and 1 point at each of the four corners, with a spacing of ≥30mm). Place the probe of the gloss meter vertically against the test point and read the value; 4) Result: Take the average value of the 5 points as the final gloss (unit: gloss unit GU).

[0060] Pearl effect (uniformity, fineness, iridescence) test: Visual observation method (compared with standard sample). Test tools: standard light source box (D65 light source, simulating natural light), magnifying glass (10x); Test steps: 1) Environmental preparation: In the standard light source box, place the test piece and the "ideal pearl effect standard sample" side by side, with the light source and test piece at a 45° angle, and the observation angle and test piece at a 45° angle; 2) Uniformity: Visually observe the distribution of the intensity of the pearl luster on the surface of the test piece, and judge whether there are local areas that are too strong / too weak (no obvious difference is preferred); 3) Fineness: Observe the pearl layer with a 10x magnifying glass to judge whether there is a visible grainy texture (no grains and smoothness are preferred); 4) Iridescence: Slowly rotate the test piece (0°-90°) and observe whether it presents a soft color change with the change of angle (such as blue, green, pink and other interference colors, with obvious but not messy layers being preferred).

[0061] The flatness test standard refers to GB / T 3810.2-2016 "Test Methods for Ceramic Tiles - Part 2: Inspection of Dimensions and Surface Quality". Test tools: straightedge (accuracy 0.02mm) and feeler gauge (accuracy 0.01mm). Test steps: 1) Place the test piece (300mm×300mm) flat on a horizontal platform and use the straightedge to fit the surface along the long side, short side and diagonal of the test piece; 2) Use the feeler gauge to measure the maximum gap between the straightedge and the surface of the test piece and record the value; 3) Result: Flatness is represented by the maximum gap (e.g., ≤0.3mm / m is excellent).

[0062] Defect testing method (pinholes, bubbles, glaze shrinkage, etc.): Visual counting method (with magnifying glass assistance); testing tools: standard light source box, 10x magnifying glass, coordinate grid board (1dm). 2 (Grid); Test steps: 1) Place the specimen under a standard light source, cover it with a coordinate grid plate, and observe it grid by grid (1dm). 2 / grid); 2) Pinholes / bubbles: Count the number of pinholes or bubbles with a diameter ≥0.5mm in each grid (≤3 per dm). 2 3) Glaze shrinkage: Observe whether there are areas where the glaze has shrunk and exposed the body, and record the area (no glaze shrinkage is considered acceptable); 4) Uneven melting of dry particles: Observe with a magnifying glass whether the dry particles are completely melted (no sharp edges remain), and record the number of unmelted particles (≤1 particle / dm²). 2 (For qualified); 5) Results: Statistical analysis of the number and distribution of various defects.

[0063] The principle of glaze hardness testing (Mohs hardness): through the mineral scratch comparison method (Mohs hardness tester, hardness level 1-10).

[0064] Abrasion resistance test (according to GB / T 3810.7-2016), test standard: GB / T 3810.7-2016 "Test methods for ceramic tiles - Part 7: Determination of abrasion resistance of glazed tile surfaces".

[0065] Acid and alkali corrosion resistance test standard: Refer to GB / T 3810.14-2016 "Ceramic tiles - Test methods - Part 14: Determination of chemical corrosion resistance".

[0066] Thermal shock resistance test standard: Refer to GB / T 3810.11-2016 "Test methods for ceramic tiles - Part 11: Determination of thermal shock resistance of glazed tiles".

[0067] Example 1

[0068] A micron-sized pearl glaze ceramic comprises a ceramic body, a color-tuning base glaze layer, and a dry granule layer. The color-tuning base glaze layer comprises, by weight, 20 parts quartz, 25 parts albite, 8 parts kaolin, 5 parts calcined zinc oxide, 7 parts calcium carbonate, 12 parts barium carbonate, 10 parts zirconium silicate, 0.2 parts color-tuning metal oxide, and 2 parts functional additives. The dry granule layer comprises, by weight, 35 parts quartz sand, 12 parts borax, 6 parts sodium carbonate, 4 parts lithium carbonate, 15 parts Bi₂O₃, 16.5 parts TiO₂, 1 part rare earth oxide, and 1 part nucleating agent. The color-tuning metal oxide is Fe₂O₃, the functional additive is MgO, the rare earth oxide is CeO₂, and the nucleating agent is P₂O₅. The preparation method includes the following steps:

[0069] Preparation of the base glaze slurry: Weigh the raw materials for the color-matching base glaze layer according to the formula ratio, then add deionized water and dispersant sodium tripolyphosphate. Use a wet ball milling method with a material:ball:water ratio of 1:2:0.7. Ball mill for 10 hours until the fineness is ≤0.1%. After milling, pass the slurry through a 250-mesh sieve and adjust the specific gravity to 1.52 g / cm³. 3 After aging for 24 hours, a base glaze slurry is obtained.

[0070] Preparation of surface reaction dry granules: Weigh the raw materials of the dry granule layer according to the formula ratio, pass them through a 200-mesh sieve, and then dry ball mill them for 3 hours until uniform to obtain a dry granule mixed powder. Melt the dry granule mixed powder at 1300℃ for 1.5 hours, then quench it in water to form glass fragments. After drying, crush the fragments, grade and sieve them to obtain surface reaction dry granules with a particle size D50 of 20-40 μm.

[0071] Preparation of the tinted base glaze layer: The base glaze slurry is evenly applied to the surface of the dry ceramic body by spraying glaze, and the thickness of the dry glaze layer is controlled to be 0.25 mm. After glazing, it is fully dried at 100℃ to form the tinted base glaze layer.

[0072] Preparation of the dry granule layer: The surface reactive dry granules are mixed with a suspending agent and uniformly coated onto the surface of the dried tinted base glaze layer using a bell-shaped glaze application method, controlling the dry granule distribution to be 180 g / m³. 2 After drying, a dry granular layer is formed;

[0073] Sintering treatment: The ceramic body forming the tinted base glaze layer and dry granule layer is sintered in an oxygen atmosphere. During the heating stage, the temperature is increased to 1230℃ at a heating rate of 35℃ / min; during the holding stage, the temperature is held at 1230℃ for 8min; during the cooling stage, the temperature is first rapidly cooled to 800℃ at a cooling rate of 120℃ / min, then cooled to 500℃ at a cooling rate of 30℃ / min, and then cooled to room temperature in the furnace to obtain micron-sized pearl glaze ceramic.

[0074] The actual image of the micron-sized pearl glaze ceramic prepared in Example 1 is shown below. Figure 2 As shown, after testing its appearance and physical properties, the results are as follows: In terms of appearance, it has high gloss (>90°); the pearl effect is uniform (no local differences in intensity), delicate (no grainy feel), and has a soft iridescent effect; the beige base color is uniform (no through-body); the flatness is excellent (warping <0.3mm / m); and there are no defects such as pinholes, bubbles, or glaze shrinkage. In terms of physical properties, it has a Mohs hardness of 6.5; abrasion resistance (GB / T 3810.7) abrasion loss of 12mg; and acid resistance (5% sulfuric acid, 24h) weight loss of 0.008g / m². 2 Alkali-resistant (5% NaOH, 24h) weight loss: 0.007 g / m³ 2 Thermal shock resistance (10 water quenchings from 150℃ to 20℃) with no cracks.

[0075] Example 2

[0076] A micron-sized pearl glaze ceramic comprises a ceramic body, a color-tuning base glaze layer, and a dry granule layer. The color-tuning base glaze layer, by weight, comprises: 22 parts quartz, 12 parts potassium feldspar, 15 parts sodium feldspar, 7 parts kaolin, 6 parts calcined zinc oxide, 6 parts calcium carbonate, 10 parts barium carbonate, 12 parts zirconium silicate, 0.2 parts color-tuning metal oxide, and 1 part functional additive. The dry granule layer, by weight, comprises: 32 parts quartz sand, 14 parts borax, 6 parts sodium carbonate, 4 parts lithium carbonate, and Bi₂O₃. The mixture contains 14 parts of TiO2, 14 parts of rare earth oxides, 0.5 parts of nucleating agent, and 1.5 parts of color-correcting metal oxide Cr2O3, the functional additive SrO, the rare earth oxide Er2O3, and the nucleating agent P2O5. The preparation method includes the following steps: the difference between the preparation method and Example 1 is that the heating rate is 30℃ / min, the temperature of the holding stage is 1240℃, and the holding time is 7min. The remaining steps are the same as in Example 1.

[0077] The actual image of the micron-sized pearl glaze ceramic prepared in Example 2 is shown below. Figure 3 As shown, after testing its appearance and physical properties, the results are as follows: In terms of appearance, it has high gloss (>88°); the pearl effect is uniform and delicate (slightly better than Example 1 in some areas); the light gray background color is uniform; the flatness is excellent; there are no obvious defects (pinholes <1 / dm). 2 In terms of physical properties, it has a Mohs hardness of 6.5; abrasion resistance (GB / T3810.7) of 13 mg; and acid resistance (5% sulfuric acid, 24 h) with a weight loss of 0.009 g / m³. 2 Alkali-resistant (5% NaOH, 24h) weight loss: 0.008 g / m³ 2 Thermal shock resistance is qualified.

[0078] Example 3

[0079] A micron-sized pearl glaze ceramic comprises a ceramic body, a color-tuning base glaze layer, and a dry granule layer. The color-tuning base glaze layer, by weight, comprises: 18 parts quartz, 16 parts potassium feldspar, 12 parts sodium feldspar, 9 parts kaolin, 4 parts calcined zinc oxide, 8 parts calcium carbonate, 14 parts barium carbonate, 15 parts zirconium silicate, 0.1 parts color-tuning metal oxide, and 2 parts functional additives. The dry granule layer, by weight, comprises: 38 parts quartz sand, 11 parts borax, 8 parts sodium carbonate, 6 parts lithium carbonate, and Bi₂O₃. The ingredients are 16 parts of TiO2, 17 parts of rare earth oxide, and 0.8 parts of nucleating agent. The color-correcting metal oxide is Co3O4, the functional additive is MgO, the rare earth oxide is CeO2, and the nucleating agent is P2O5. The preparation method differs from that of Example 1 in that the heating rate is 40℃ / min, the temperature of the holding stage is 1220℃, and the holding time is 6min. All other steps are the same as those in Example 1.

[0080] The actual image of the micron-sized pearl glaze ceramic prepared in Example 3 is shown below. Figure 4 As shown, after testing its appearance and physical properties, the results are as follows: In terms of appearance, it has high gloss (>92°); the pearl effect is uniform and delicate; the base color is pure white (no impurities); the flatness is excellent; and there are no defects. In terms of physical properties, the Mohs hardness is 7.0; the abrasion resistance (GB / T 3810.7) is 10mg; and the acid resistance (5% sulfuric acid, 24h) is a weight loss of 0.006g / m³. 2 Alkali-resistant (5% NaOH, 24h) weight loss 0.005g / m³ 2 Thermal shock resistance is qualified.

[0081] Comparative Example 1 (Traditional single-layer glaze, no dry particles, with added pearlizing agent)

[0082] A ceramic material includes a ceramic body and a base glaze layer. The raw materials of the base glaze, by weight, include: 25 parts quartz, 15 parts potassium feldspar, 15 parts sodium feldspar, 10 parts kaolin, 10 parts calcium carbonate, 5 parts zinc oxide, and 5 parts pearlizing agent. Its preparation method is basically the same as that in Example 1, except that it does not include the preparation of a dry granule layer, and the holding temperature is 1200℃ for 5 minutes.

[0083] After testing the appearance and physical properties of the ceramic prepared in Comparative Example 1, the results are as follows: In terms of appearance, the gloss is low (<70°); the pearl effect is messy (local aggregation) and has a strong grainy texture (no fineness); the base color is uneven (through the body); the flatness is poor (orange peel texture); and there are more than 5 pinholes / dm². 2 In terms of physical properties, it has a Mohs hardness of 5.0; abrasion resistance (GB / T 3810.7) with an abrasion loss greater than 30 mg; and acid resistance (5% sulfuric acid, 24h) with a weight loss greater than 0.05 g / m³. 2Alkali-resistant (5% NaOH, 24h) with a weight loss greater than 0.04 g / m³ 2 The thermal shock resistance (5 cycles) showed cracks. Comparative analysis revealed that the poor performance of Comparative Example 1 was due to the lack of a "double-layer structure + interface reaction," the pearl agent was only physically mixed (and could not be evenly distributed), there was no dry particle reinforcement (low hardness), gas could not be discharged when the single-layer glaze melted (many pinholes), and there was no slow cooling (high stress and poor thermal shock resistance).

[0084] Comparative Example 2 (Firing temperature too low)

[0085] A micron-sized pearl glaze ceramic includes a ceramic body, a colored base glaze layer, and a dry granule layer. Its formula composition is the same as that of Example 1. The only difference between the preparation method and Example 1 is that the sintering temperature during the heat preservation stage is 1150℃.

[0086] After testing the appearance and physical properties of the ceramic prepared in Comparative Example 2, the results are as follows: In terms of appearance, the gloss is low (<72°); the pearl effect is weak (insufficient microcrystal formation) and uneven; the base color is dark (incomplete melting); the flatness is poor (insufficient leveling); and there are more than 3 bubbles / dm³. 2 (Gas not discharged); In terms of physical properties, Mohs hardness 5.5; abrasion resistance wear loss >22mg; acid resistance weight loss 0.025g / m 2 (Poor structure); thermal shock resistance is acceptable (but glaze strength is low). The reasons for the performance difference compared with Example 1 are: the reaction temperature of 1150℃ was not reached, and the dry particles and the base glaze could not react fully (few BiTiO microcrystals, weak pearl effect); the base glaze was not completely melted (poor leveling, low smoothness); gas was not discharged (bubbles); and the structure was loose (hardness and acid and alkali resistance decreased).

[0087] Comparative Example 3 (dry particle size too large)

[0088] A micron-sized pearl glaze ceramic includes a ceramic body, a colored base glaze layer, and a dry granule layer. Its formula composition is the same as that of Example 1. The only difference between the preparation method and Example 1 is that the particle size D50 of the surface reactive dry granules obtained by grading and sieving is 60 μm.

[0089] After testing the appearance and physical properties of the ceramic prepared in Comparative Example 3, the results are as follows: In terms of appearance, the gloss is low (<75°); the pearl effect has a strong grainy texture (visible protrusions) and is uneven (excessive brightness in areas with large grains); the base color is partially transparent; the flatness is poor (uneven texture); the dry particles are not melted evenly (unmelted edges). In terms of physical properties, the Mohs hardness is 5.5; the wear resistance is >25mg (protrusions are easily worn); and the acid resistance shows a weight loss of 0.02g / m³. 2(Corrosion at the crevice); thermal shock resistance (8 cycles) localized cracking. The reasons for the performance difference compared with Example 1 are as follows: the dry particle size is 60μm (far exceeding 20-40μm), and the dry particles cannot be completely melted during firing (residual particles), resulting in a rough pearl effect; the raised parts of the particles are easily worn (poor wear resistance); the gaps between the particles and the base glaze are prone to dirt / corrosion (decreased acid and alkali resistance).

[0090] Comparative Example 4 (excessive dry particle distribution)

[0091] A micron-sized pearl glaze ceramic comprises a ceramic body, a colored base glaze layer, and a dry granule layer. Its formulation is the same as in Example 1, but the preparation method differs from Example 1 only in that the dry granule dispersion is controlled at 400 g / m³ during the preparation of the dry granule layer. 2 .

[0092] After testing the appearance and physical properties of the ceramic prepared in Comparative Example 4, the results are as follows: In terms of appearance, the gloss is uneven (some areas are too bright); the pearl effect is too strong (the "realistic" feel lacks dynamism); there is localized glaze buildup (glaze shrinkage); the flatness is poor (flow marks); there are more than 3 glaze cracks per piece. In terms of physical properties, the Mohs hardness is 6.0; the wear resistance loss is 18 mg (easily detached at the buildup areas); and the acid resistance loss is 0.015 g / m³. 2 The thermal shock resistance (3 cycles) showed obvious cracking. The reason for the performance difference compared to Example 1 is attributed to: 400g / m³ 2 Excessive dispersion leads to dry particle accumulation (inability to level), localized over-melting (glaze shrinkage); excessively thick glaze layer (high stress, glaze cracking); weak bonding between the accumulated area and the base glaze (easy to fall off, reduced wear resistance).

[0093] It is understood that those skilled in the art can make equivalent substitutions or modifications to the technical solution and inventive concept of the present invention, and all such substitutions or modifications should fall within the protection scope of the appended claims.

Claims

1. A micron-sized pearl glaze ceramic, characterized in that, The material comprises a ceramic body, a color-tuning base glaze layer, and a dry granule layer. The raw materials of the color-tuning base glaze layer, by weight, include: 15-25 parts quartz, 20-30 parts feldspar, 5-10 parts kaolin, 3-8 parts calcined zinc oxide, 5-10 parts calcium carbonate, 8-15 parts barium carbonate, 8-15 parts zirconium silicate, 0.05-0.5 parts color-tuning metal oxide, and 1-3 parts functional additives. The raw materials of the dry granule layer, by weight, include: 30-40 parts quartz sand, 10-15 parts borax, 5-8 parts sodium carbonate, 3-6 parts lithium carbonate, 10-18 parts Bi₂O₃, 10-18 parts TiO₂, 0.5-2 parts rare earth oxides, and 0.5-2 parts nucleating agent.

2. The micron-sized pearl glaze ceramic according to claim 1, characterized in that, The feldspar is one or both of potassium feldspar and sodium feldspar; the coloring metal oxide is one or more of Fe2O3, Cr2O3 and Co3O4.

3. The micron-sized pearl glaze ceramic according to claim 1, characterized in that, The functional additive is one or more of bentonite, sodium carboxymethyl cellulose, MgO and SrO.

4. The micron-sized pearl glaze ceramic according to claim 1, characterized in that, The rare earth oxide is one or both of CeO2 and Er2O3; the nucleating agent is P2O5.

5. A method for preparing micron-sized pearl glaze ceramic as described in any one of claims 1-4, characterized in that, Including the following steps: Weigh the raw materials for the color-matching base glaze according to the formula ratio, then add deionized water and dispersant sodium tripolyphosphate, and then sieve the mixture after wet ball milling to obtain the base glaze slurry. Weigh the raw materials of the dry granule layer according to the formula ratio, sieve them, and then dry ball mill them until uniform to obtain dry granule mixed powder. Melt the dry granule mixed powder and quench it in water to form glass fragments. After drying, crush it and grade it to obtain surface reaction dry granules. A base glaze slurry is evenly applied to the surface of the ceramic body using a spray glazing method, and after drying, a colored base glaze layer is formed. The surface reaction dry granules are mixed with a suspending agent and evenly coated onto the surface of the dry tinted base glaze layer using a bell jar glazing method. After drying, a dry granule layer is formed. Micron-sized pearl glaze ceramics are obtained by sintering ceramic bodies that form a tinted base glaze layer and a dry granule layer under an oxygen atmosphere.

6. The method for preparing micron-sized pearl glaze ceramics according to claim 5, characterized in that, The steps for obtaining the base glaze slurry by wet ball milling and sieving include: wet ball milling with a material:ball:water ratio of 1:2:0.6-0.8 for 6-12 hours until the fineness is ≤0.1%; passing the slurry through a 250-mesh sieve after milling; and adjusting the slurry specific gravity to 1.50-1.55 g / cm³. 3 After aging for 20-30 hours, a base glaze slurry is obtained.

7. The method for preparing micron-sized pearl glaze ceramics according to claim 5, characterized in that, In the step of melting the dry granular mixed powder, the melting temperature is 1250-1350℃ and the time is 1-2 hours.

8. The method for preparing micron-sized pearl glaze ceramics according to claim 5, characterized in that, The sintering process for the ceramic body forming the tinted base glaze layer and the dry granule layer under an oxygen atmosphere includes a heating stage, a holding stage, and a cooling stage. In the heating stage, the temperature is increased to 1200-1260℃ at a heating rate of 30-40℃ / min. In the holding stage, the temperature is held at 1200-1260℃ for 5-10 minutes. In the cooling stage, the temperature is first rapidly cooled to 750-850℃ at a cooling rate of 100-130℃ / min, then cooled to 450-550℃ at a cooling rate of 20-40℃ / min, and then cooled to room temperature in the furnace.

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