Bright ceramic tile and preparation method thereof

Abstract

The invention discloses a bright ceramic tile and a preparation method thereof, and relates to the technical field of ceramic tiles. The bright ceramic tile comprises a bottom blank, a ground glaze layer, a mold texture layer and a high-transmittance glaze layer, and the ground glaze layer is prepared from, by mass, 25%-30% of quartz, 20%-35% of feldspar, 15%-20% of clay, 5%-10% of calcium carbonate, 3%-5% of zinc oxide and 10%-15% of zircon sand; the high-transmittance glaze layer is prepared from the following chemical components in percentage by mass: 50 to 60 percent of SiO2, 10 to 15 percent of Al2O3, 7 to 9 percent of ZnO, 5 to 8 percent of SrO, 6 to 12 percent of CaO, 3 to 6 percent of SO3, 2 to 5 percent of B2O3 and 1 to 3 percent of BaO. The core contradictions of polishing-free and surface defects, texture retention and permeability and leveling and exhausting of large-size mold surface ceramic tiles are successfully solved, mirror-level flatness of products is achieved, the defect rate is smaller than or equal to 0.3%, the light transmittance is larger than or equal to 85%, the yield can reach 92% to the maximum, and meanwhile the polishing procedure is omitted.

Description

Technical Field

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

[0002] In the field of architectural decoration, molded ceramic tiles with a large size of 600mm×1200mm and above have become an important choice in the high-end decoration market due to their combination of the natural texture of three-dimensional patterns and the spatial extension of large sizes. However, their traditional production technology has an irreconcilable contradiction: traditional high-gloss ceramic tiles rely on mechanical polishing to achieve the transparency of the glaze, but the surface of molded ceramic tiles has an uneven texture. Polishing will smooth out the raised parts of the texture, resulting in the destruction of the three-dimensional texture and the loss of texture details; if not polished, the glaze is prone to defects such as pinholes, prickly heat blisters, and orange peel texture due to insufficient leveling, and the gloss and flatness cannot meet the standards. Large-sized ceramic tiles of 600mm×1200mm and above are significantly more difficult to level due to their large size and wide glaze coverage: if the glaze layer is too thick in some areas, it will easily lead to glaze flow and accumulation, while if it is too thin, it will not be able to fill the texture depressions; at the same time, the uneven distribution of thermal stress during the firing of large-sized bodies is prone to cracking due to insufficient glaze fluidity, and the yield rate is generally less than 70%.

[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 glossy ceramic tile and its preparation method, which aims to solve the problems that the prior art cannot simultaneously solve the problems of preserving the texture of the tile mold, achieving zero defects on the surface without polishing, and ensuring the stability of large-scale production.

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

[0006] A glossy ceramic tile includes a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer. The raw materials of the base glaze layer, by weight percentage, include: 25-30% quartz, 20-35% feldspar, 15-20% clay, 5-10% calcium carbonate, 3-5% zinc oxide, and 10-15% zircon sand. The chemical composition of the high-transparency glaze layer, by weight percentage, includes: 50-60% SiO2, 10-15% Al2O3, 7-9% ZnO, 5-8% SrO, 6-12% CaO, 3-6% SO3, 2-5% B2O3, and 1-3% BaO.

[0007] The glossy ceramic tile, wherein the feldspar is one or both of sodium feldspar and potassium feldspar.

[0008] A method for preparing glossy ceramic tiles as described in this invention, comprising the steps of:

[0009] The raw materials for the base glaze layer are fed into a ball mill according to the formula ratio, and deionized water is added for ball milling to obtain the base glaze slurry.

[0010] The chemical composition of the high-transparency glaze is fed into a ball mill according to the formula ratio, and deionized water is added for ball milling to obtain a high-transparency glaze slurry.

[0011] A base glaze slurry is applied to the surface of the body using a glazing process, and after drying, a base glaze layer is formed.

[0012] A pre-designed mold texture is printed on the surface of the base glaze layer using inkjet printing to form a mold texture layer.

[0013] A high-transparency glaze slurry is applied to the surface of the printed blank using a glazing process, and after drying, a high-transparency glaze layer is formed.

[0014] The ceramic tile is obtained by firing the body that forms the base glaze layer and the high-transparency glaze layer.

[0015] The method for preparing glossy ceramic tiles includes the step of preparing the base glaze slurry, in which the raw materials of the base glaze layer and deionized water are added to a ball mill at a mass ratio of 1:0.4, the ball milling media is alumina balls, the ball mill speed is controlled at 250-350 r / min, the ball milling time is 6-8 h, and the glaze slurry is passed through a 325 mesh sieve for later use.

[0016] In the preparation method of the glossy ceramic tile, the specific gravity of the base glaze slurry is 1.8-1.9 g / cm³. 3 .

[0017] The method for preparing the glossy ceramic tile includes the step of preparing the high-transparency glaze slurry, in which the chemical composition of the base glaze layer and deionized water are added to a ball mill at a mass ratio of 1:0.45, the ball milling media is alumina balls, the ball mill speed is controlled at 300-400 r / min, the ball milling time is 8-10 h, and the glaze slurry is used after passing through a 325 mesh sieve.

[0018] In the preparation method of the glossy ceramic tile, the specific gravity of the high-transparency glaze slurry is 1.8-1.9 g / cm³. 3 .

[0019] The method for preparing the glossy ceramic tile includes a firing process for the body forming the base glaze layer and the high-transparency glaze layer, comprising a heating stage, a holding stage, and a cooling stage. In the heating stage, the temperature is increased to 550-650℃ at a heating rate of 3℃ / min, then increased to 950-1050℃ at a heating rate of 5℃ / min, and then increased to 1230-1280℃ at a heating rate of 6℃ / min. In the holding stage, the temperature is held at 1230-1280℃ for 10-20 minutes. In the cooling stage, the temperature is first cooled to 750-850℃ at a cooling rate of 5℃ / min, then cooled to 450-550℃ at a cooling rate of 3℃ / min, and finally cooled to room temperature in the furnace.

[0020] Beneficial Effects: This invention successfully solves the core contradictions of "no polishing and surface defects," "texture retention and transparency," and "leveling and air venting" in large-format molded ceramic tiles through a formulation design with a high proportion of ZnO and SrO synergistic flux, a bubble self-healing mechanism regulated by SO3, and crystal phase control via step-firing. The product achieves mirror-level flatness, a defect rate of ≤0.3%, and a light transmittance of ≥85%, with a yield rate of 92%. Simultaneously, it eliminates the polishing process, reducing energy consumption and pollution. This invention fills a gap in the industry, providing a feasible solution for the industrial application of no-polishing technology in the ceramic industry, and possesses significant technological innovation and market value. Attached Figure Description

[0021] Figure 1 This is a flowchart of a method for preparing a glossy ceramic tile according to the present invention.

[0022] Figure 2 This is a photograph of the glossy ceramic tile prepared in Example 1 of the present invention.

[0023] Figure 3 This is a photograph of the glossy ceramic tile prepared in Example 2 of the present invention.

[0024] Figure 4 This is a photograph of the glossy ceramic tile prepared in Example 3 of the present invention.

[0025] Figure 5 This is a physical image of the ceramic tile prepared in Comparative Example 2 of the present invention.

[0026] Figure 6 This is a physical image of the ceramic tile prepared in Comparative Example 3 of the present invention.

[0027] Figure 7 This is a physical image of the ceramic tile prepared in Comparative Example 4 of the present invention. Detailed Implementation

[0028] This invention provides a glossy ceramic tile 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.

[0029] This invention provides a glossy ceramic tile, comprising a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer. The raw materials of the base glaze layer, by mass percentage, include: 25-30% quartz, 20-35% feldspar, 15-20% clay, 5-10% calcium carbonate, 3-5% zinc oxide, and 10-15% zircon sand. The chemical composition of the high-transparency glaze layer, by mass percentage, includes: 50-60% SiO2, 10-15% Al2O3, 7-9% ZnO, 5-8% SrO, 6-12% CaO, 3-6% SO3, 2-5% B2O3, and 1-3% BaO.

[0030] This invention relates to a glossy ceramic tile employing a dual-layer glaze system consisting of a base glaze and a high-transparency glaze. The base glaze provides a stable substrate, while the high-transparency glaze achieves leveling, air release, and gloss effects. Specifically, in the base glaze layer, 25-30% quartz provides SiO2 to form the glaze layer framework; 20-35% feldspar, including at least one of sodium feldspar and potassium feldspar, introduces K2O and Na2O to lower the melting temperature; 15-20% clay enhances the suspension of the base glaze slurry and regulates drying shrinkage; 5-10% calcium carbonate acts as a flux to help reduce viscosity; 3-5% zinc oxide improves the fluidity of the base glaze and promotes bonding with the body; and 10-15% zircon sand enhances hiding power and prevents color interference with the body.

[0031] In the high-transparency glaze layer, a high proportion of ZnO (5-10%) and SrO (6.22%) serve as the main flux, working synergistically with B2O3 (2-5%) to form a "wide temperature range gradient melting system". It can maintain low viscosity (100-300 mPa·s) in the range of 1100-1300℃, and the leveling time is extended by more than 50% compared with traditional glazes. This ensures that the high-transparency glaze slurry can fully fill the uneven areas of the mold texture layer (depth 0.1-0.3mm) and achieve self-leveling.

[0032] The high-transparency glaze uses ZnO and SrO as its base formula. During the sintering and cooling stage, these two components induce the precipitation of submicron-sized zinc silicosite Zn2SiO4 and strontium-containing microcrystalline SrSiO3. Their refractive index (1.68-1.72) is close to that of the glass phase (1.58-1.62), which reduces light scattering and improves light transmittance. Furthermore, the formed microcrystals are dispersed in the glass phase in a "pinning" manner, which can inhibit the propagation of microcracks (length ≤10μm) in the glaze layer and fill the gaps in the glass phase, thereby increasing the glaze density by more than 20%. The hardness (Mohs hardness ≥6) and wear resistance (wear resistance depth ≤0.02mm) both meet the standards. The combined use of these two components achieves a three-in-one effect of "minimizing light scattering (high transparency), eliminating micro-defects (zero defects), and strengthening the structure (high hardness)," breaking through the bottleneck of traditional non-polished glazes where "transparency and strength cannot be simultaneously achieved."

[0033] In high-transparency glazes, by precisely controlling the mass percentage of SiO2 to 50-55% and the mass percentage of Al2O3 to 10-15%, the rigid framework of traditional glazes is weakened, giving the high-transparency glaze slurry "soft fluidity" at high temperatures, while preventing the glaze layer from collapsing due to an excessively weak framework. If the amount of Al2O3 exceeds 15%, the viscosity of the slurry will increase sharply, leading to leveling failure; if the amount of Al2O3 is less than 10%, the glaze layer is prone to collapse.

[0034] In high-transparency glazes, 3-6% SO3 acts as a surface-active component, reducing the surface tension of the melt to 30-40 mN / m (compared to approximately 50-60 mN / m for traditional glazes). This promotes the fusion of microbubbles (≤5 μm in diameter) into larger bubbles (≥20 μm in diameter), facilitating their upward escape. By reducing the surface tension of the melt, gas release is concentrated in the early stages of glaze melting (1000-1100℃), when the glaze viscosity remains low (≤500 mPa·s). This allows the bubbles to escape completely before the glaze layer seals, achieving "bubble self-healing." If the SO3 content is below 3%, the gas removal rate will drop to 80%, and pinholes on the glaze surface will increase. If the SO3 content is above 6%, excessive gas release will generate new bubbles.

[0035] The glossy ceramic tile provided by this invention achieves for the first time the synergy of "no polishing required, mirror-like flatness, high transparency, and three-dimensional texture" in molded ceramic tiles. The glaze defect rate is ≤0.3%, the light transmittance is ≥85%, and the texture details are well preserved, meeting the dual requirements of high-end decoration for texture and aesthetics. At the same time, the submicron-level microcrystalline reinforcement makes the glaze Mohs hardness ≥6.5 and the wear resistance depth ≤0.02mm, meeting the standards for polished tiles and solving the problem of traditional no-polish glazes being "beautiful but not durable".

[0036] In some embodiments, a method for preparing glossy ceramic tiles as described in this invention is also provided, such as... Figure 1 As shown, it includes the following steps:

[0037] S10. Add the raw materials of the base glaze layer into a ball mill according to the formula ratio, add deionized water and ball mill to obtain the base glaze slurry.

[0038] S20. The chemical composition of the high-transparency glaze is fed into a ball mill according to the formula ratio, and deionized water is added for ball milling to obtain a high-transparency glaze slurry.

[0039] S30. Apply a base glaze slurry to the surface of the body using a glazing process, and form a base glaze layer after drying.

[0040] S40. Use inkjet printing to print a pre-designed mold texture on the surface of the base glaze layer to form a mold texture layer;

[0041] S50. A high-transparency glaze slurry is applied to the surface of the printed blank using a glazing process, and a high-transparency glaze layer is formed after drying.

[0042] S60. The body forming the base glaze layer and the high-transparency glaze layer is fired to obtain the glossy ceramic tile.

[0043] Specifically, in the preparation of the base glaze slurry, the raw materials for the base glaze layer and deionized water are added to a ball mill at a mass ratio of 1:0.4. Alumina balls are used as the milling media. The ball mill speed is controlled at 250-350 r / min, and the milling time is 6-8 hours, until the glaze slurry has a residue of ≤0.5% after passing through a 325-mesh sieve, ensuring that the base glaze slurry particles are fine. Finally, the specific gravity of the base glaze slurry is adjusted to 1.8-1.9 g / cm³ by adding water or raw materials. 3 .

[0044] In the preparation of the high-transparency glaze slurry, the chemical composition of the base glaze layer and deionized water are added to a ball mill at a mass ratio of 1:0.45. Alumina balls are used as the milling media. The ball mill speed is controlled at 300-400 r / min, and the milling time is 8-10 h, until the glaze slurry has a residue of ≤0.5% after passing through a 325 mesh sieve. Finally, the specific gravity of the high-transparency glaze slurry is adjusted to 1.8-1.9 g / cm³ by adding water or raw materials. 3 .

[0045] In the process of applying a base glaze slurry to the surface of the blank using a glazing process, and then drying it to form a base glaze layer, the following steps are first taken: using raw materials such as clay, quartz, and feldspar, the blank is pressed into a 600mm×1200mm×10mm blank (pressing pressure 30MPa, holding time 10 seconds), and dried until the moisture content is ≤0.5% (drying temperature 200℃, time 20 minutes) to obtain the blank. Then, using a glazing process, a base glaze slurry is applied to the surface of the blank. For example, the amount of glaze applied is controlled to be 100-120g (corresponding to a 400mm×600mm tray) to ensure uniform glaze coverage with a thickness of about 0.15-0.2mm. The blank is then dried at 180℃ for 15 minutes until the moisture content is ≤1% to form the base glaze layer.

[0046] Next, a pre-designed mold texture is printed onto the surface of the base glaze layer using inkjet printing, forming a mold texture layer. Printing textures onto the base glaze layer is a crucial step in giving the tiles a unique decorative effect, and ensuring good compatibility between the ink and the base glaze is key to achieving high-quality printing results and avoiding defects such as air bubbles. For example, inkjet printing inks include 5-25% inorganic non-metallic pigments, 50-55% deionized water, 10-15% ethylene glycol, 3-5% dispersant, 5-8% humectant, and 0.1-0.5% pH adjuster. The inorganic pigments can be iron oxide, cobalt blue pigment (CoAl2O4), cobalt green pigment (CoO·ZnO·Al2O3), iron brown pigment (Fe2O3·Cr2O3·ZnO), chrome green pigment (Cr2O3 or Cr2O3·Al2O3), etc. As the core coloring substance of the ink, inorganic non-metallic pigments are usually fine inorganic compounds with excellent stability and lightfastness. In the ink system for large-format glossy ceramic tiles, the pigment particle size must be strictly controlled to be less than 1 micrometer, with an extremely narrow particle size distribution and no strong agglomeration between particles. This is because smaller and uniformly dispersed particles ensure smooth ink flow during printing, preventing nozzle clogging, and ensuring vibrant, pure colors after high-temperature firing. The dispersant is sodium polycarboxylate, used to adsorb pigment particles and prevent agglomeration; the humectant is glycerol, which enhances moisture retention and prevents ink from drying at the nozzle; and the pH adjuster is ammonia, which stabilizes the ink pH at 7.5-8.0.

[0047] Then, a glazing process is used to apply a high-transparency glaze paste to the surface of the printed blank. The amount of glaze applied is controlled to be 130-140g (corresponding to a 400mm×600mm tray), and the thickness of the glaze layer is about 0.2-0.25mm (to ensure that the mold texture is filled and the ink layer is covered). It is then dried at 200℃ for 10-20 minutes until the moisture content is ≤1%, forming a high-transparency glaze layer.

[0048] Finally, the body with the base glaze layer and high-transparency glaze layer is fired. The firing process includes a heating stage, a holding stage, and a cooling stage. In the heating stage, the temperature is increased to 550-650℃ at a heating rate of 3℃ / min, then increased to 950-1050℃ at a heating rate of 5℃ / min, and then increased to 1230-1280℃ at a heating rate of 6℃ / min. In the holding stage, the temperature is held at 1230-1280℃ for 10-20 minutes. In the cooling stage, the temperature is first cooled to 750-850℃ at a cooling rate of 5℃ / min, then cooled to 450-550℃ at a cooling rate of 3℃ / min, and finally cooled to room temperature in the furnace.

[0049] Specifically, the main purpose of dividing the heating stage into three stages in this embodiment is to balance thermal stress and venting rhythm, and avoid early defects. In the first stage, the temperature is raised to 550-650℃ at a rate of 3℃ / min. This stage is the period for the removal of physical water and organic matter: the physical water (moisture content ≤0.5% but still trace amounts) remaining in the body and glaze, and the organic additives (such as dispersants) in the base glaze / ink need to evaporate slowly. If the temperature rises too quickly (e.g., >5℃ / min), the water and organic matter will generate a large amount of gas due to "instantaneous vaporization". At this time, the glaze has not yet melted (it is still solid), and the gas cannot be discharged through the glaze, which easily forms bubbles at the body-glaze interface (which become pinholes after cooling). At the same time, the difference in thermal expansion coefficients between the body and the glaze is most sensitive in the low-temperature range. Low-speed heating allows both to expand synchronously, avoiding early glaze cracks caused by "glaze shrinkage lagging behind the body". The second stage involves heating to 950-1050℃ at a rate of 5℃ / min. This stage is the "initial melting and crystal phase preparation period of the glaze." Above 650℃, the feldspar and calcium carbonate in the base glaze begin to soften (melting point around 800℃). Strong fluxes such as ZnO and SrO in the high-transparency glaze begin to function, and the glaze gradually transitions from a solid state to a semi-molten state (viscosity > 1000 mPa·s). Medium-speed heating allows the glaze to "gradually soften"—avoiding both excessive softening (premature sagging) caused by slow heating and uneven melting (some areas still solid, others semi-molten) caused by rapid heating. Simultaneously, the quartz in the body undergoes a crystal transformation during this stage (α-quartz → β-quartz at 573℃). Medium-speed heating buffers the volume change caused by the phase transformation (expansion rate approximately 0.8%), preventing cracking of the body. The third stage involves heating at a rate of 6℃ / min to 1230-1280℃. This stage is the "complete melting and rapid leveling period of the glaze." Above 1050℃, the synergistic effect of ZnO / SrO in the high-transparency glaze becomes prominent, and the glaze viscosity decreases rapidly (to around 200 mPa·s at 1230-1280℃), entering the low-viscosity leveling window. High-speed heating shortens the time to reach the target temperature, avoiding prolonged residence in the "medium viscosity range (500-1000 mPa·s)." If the residence time is too long, the glaze layer is prone to being too thin at the raised areas of the mold texture due to "early over-leveling" (which is prone to wear after cooling). At the same time, high-speed heating allows the glaze to remain in an "active molten state" (with strong molecular fluidity) when reaching 1230-1280℃, storing kinetic energy for sufficient leveling and bubble removal in the subsequent heat preservation stage.

[0050] The main purpose of the heat preservation stage in this embodiment is to achieve dual optimization of leveling and venting, eliminating surface defects. 1230-1280℃ is the optimal melting temperature for high-transparency glaze (ZnO / SrO has high solubility at this temperature), and the glaze viscosity is stable at around 200 mPa·s (with the strongest leveling ability). 10-20 minutes of heat preservation allows the glaze sufficient time to self-level, filling the fine depressions (depth ≤0.3mm) of the mold texture through surface tension, eliminating local ripples caused by rapid heating. At the same time, the glaze spreads evenly under gravity, ensuring that the thickness difference of the glaze layer between the edge and center of large-format tiles is ≤5% (avoiding edge accumulation). The heat preservation stage is also the last window for bubble discharge. After the glaze melts, the tiny bubbles (diameter ≤5μm) remaining inside will float to the surface due to buoyancy in a low viscosity environment. In addition, SO3 reduces the surface tension of the melt, promotes the fusion of bubbles into larger bubbles (diameter ≥20μm), and accelerates their discharge. 10-20 minutes just covers the complete cycle of "bubble rising-fusion-escape". Experiments show that: <10 minutes, the bubble discharge rate is only 85%, and >20 minutes, the glaze layer is prone to collapse due to over-firing.

[0051] The purpose of using stepped cooling in this embodiment is to precisely induce the precipitation of crystalline phases and balance light transmittance and structural strength. The first stage involves cooling to 750-850℃ at a rate of 5℃ / min. This stage is the microcrystalline nucleation period: slow cooling from the melting temperature causes the glaze to transform from a liquid to a solid state, and Zn... 2+ 、Sr 2+ Si 4+The plasma begins to arrange itself in an orderly manner. A cooling rate of 5°C / min allows the ions time to aggregate and form "microcrystal nuclei" (such as the nuclei of zinc silicosite Zn₂SiO₄), but prevents excessive growth (to avoid excessively large nuclei). If the cooling is too rapid (e.g., >10°C / min), the ions do not have enough time to aggregate, resulting in insufficient nuclei formation; if the cooling is too slow (e.g., <3°C / min), the nuclei will grow prematurely, affecting subsequent uniform precipitation. The second stage involves cooling to 450-550℃ at a rate of 3℃ / min. This stage is the "submicron-scale crystallite growth period": a "rapid growth period" for zinc silicosite Zn₂SiO₄ and strontium-containing microcrystals SrSiO₃. The slow cooling rate of 3℃ / min allows the microcrystals to grow slowly based on the crystal nuclei, ultimately controlling the particle size to 0.2-0.5μm (submicron level). The refractive index of this particle size (1.68-1.72) is close to that of the glass phase (1.58-1.62), resulting in minimal light scattering (without affecting transmittance). Simultaneously, the microcrystals can "pin" microcracks (length ≤10μm) in the glass phase, enhancing the density of the glaze. If the cooling is too fast, the microcrystal growth is insufficient (particle size <0.1μm), resulting in a weak strengthening effect; if the cooling is too slow, the microcrystals become too large (>1μm), increasing light scattering (decreasing transmittance). Finally, the furnace is cooled to room temperature. At this stage, the glaze layer is completely solidified (glass phase + stable microcrystalline structure), but there is still a trace amount of residual thermal stress (mainly from the difference in the coefficients of thermal expansion of the body and glaze). Cooling in the furnace allows the stress to be released slowly (stress release rate).

[0052] ≥90%) to avoid late-stage cracking caused by "excessive temperature difference between surface and interior" due to sudden cooling.

[0053] The present invention will be further explained and illustrated below through specific embodiments:

[0054] Example 1

[0055] A glossy ceramic tile includes a base, a base glaze layer, a molded texture layer, and a high-transparency glaze layer. The base glaze layer comprises, by weight percentage: 28% quartz, 15% potassium feldspar, 15% sodium feldspar, 18% clay, 8% calcium carbonate, 4% zinc oxide, and 12% zircon sand. The high-transparency glaze layer comprises, by weight percentage: 55% SiO2, 13% Al2O3, 8% ZnO, 6% SrO, 8% CaO, 5% SO3, 3% B2O3, and 2% BaO. Its preparation method includes the following steps:

[0056] Preparation of the base glaze slurry: Weigh the base glaze raw materials according to the formula, crush them to a particle size ≤5mm using a jaw crusher, and remove impurities by sieving (to ensure uniformity in subsequent ball milling); add the base glaze raw materials and water to a ball mill at a mass ratio of 1:0.4, ball mill for 6-8 hours at a speed of 300 r / min, and control the specific gravity of the glaze slurry to 1.88 g / cm³. 3 The glaze slurry is passed through a 325-mesh sieve and set aside for later use;

[0057] Preparation of high-transparency glaze slurry: Add the high-transparency glaze raw material and water to a ball mill at a mass ratio of 1:0.45. Mill for 8-10 hours at a speed of 350 r / min (ensuring uniform dispersion of ZnO and SrO), controlling the glaze slurry specific gravity to 1.88 g / cm³. 3 After passing through a 325-mesh sieve, it is ready for use.

[0058] Preparation of blanks: Using clay, quartz, feldspar and other blank raw materials, press them into 600mm×1200mm×10mm blanks (pressing pressure 30MPa, holding time 10 seconds), and dry them until the moisture content is ≤0.5% (drying temperature 200℃, time 20 minutes).

[0059] Preparation of the base glaze layer: The base glaze slurry is applied to the surface of the body using a glazing process. For example, the amount of glaze applied is controlled to be 110g (corresponding to a 400mm×600mm tray) to ensure uniform coverage of the glaze layer with a thickness of about 0.15-0.2mm. The glaze is then dried at 180℃ for 15min until the moisture content is ≤1% to form the base glaze layer.

[0060] Preparation of the mold texture layer: A pre-designed mold texture is printed on the surface of the base glaze layer using inkjet printing to form the mold texture layer. For example, the inkjet printing ink includes 20% inorganic non-metallic pigment, 55% deionized water, 13% ethylene glycol, 5% dispersant, 6.5% humectant, and 0.5% pH adjuster. The inorganic non-metallic pigment is iron oxide, the dispersant is sodium polycarboxylate, the humectant is glycerol, and the pH adjuster is ammonia.

[0061] Preparation of high-transparency glaze layer: Using a glazing process, a high-transparency glaze slurry is applied to the surface of the printed blank. The amount of glaze applied is controlled at 135g (corresponding to a 400mm×600mm tray), and the thickness of the glaze layer is about 0.2-0.25mm (to ensure that the mold texture is filled and the ink layer is covered). It is dried at 200℃ for 10-20min until the moisture content is ≤1% to form a high-transparency glaze layer.

[0062] Firing treatment: The body forming the base glaze layer and the high-transparency glaze layer is subjected to firing treatment. The firing treatment includes a heating stage, a holding stage, and a cooling stage. In the heating stage, the temperature is increased to 600℃ at a heating rate of 3℃ / min, then increased to 1000℃ at a heating rate of 5℃ / min, and then increased to 1250℃ at a heating rate of 6℃ / min. In the holding stage, the temperature is held at 1250℃ for 15 minutes. In the cooling stage, the temperature is first cooled to 800℃ at a cooling rate of 5℃ / min, then cooled to 500℃ at a cooling rate of 3℃ / min, and finally cooled to room temperature in the kiln to obtain glossy ceramic tiles.

[0063] The glossy ceramic tile prepared in Example 1 is as follows: Figure 2 As shown, its glaze surface smoothness is mirror-like, with no ripples visible to the naked eye and no unevenness to the touch. The mold texture is clear and completely covered by the glaze layer, presenting a "high-transparency crystal layer" effect. The transparency of the body's base color and texture is close to that of polished tiles. Its surface defects include a pinhole and prickly heat blister defect rate of 0.2%, no orange peel texture, and a dense and smooth glaze surface with a silky feel. Its light transmittance is 88% (at a thickness of 5mm), close to that of polished tiles. Its mechanical properties include a Mohs hardness of 6.5 and a wear resistance depth of 0.015mm. The yield rate is 92%.

[0064] In this embodiment, a high proportion of ZnO and SrO acts as a strong flux, significantly reducing the high-temperature viscosity of the glaze. Combined with the fluxing effects of B2O3 and BaO, a wide-temperature-range gradient melting system is formed, enabling the glaze to have an ultra-long leveling time during firing, fully filling the uneven areas of the mold texture and achieving self-leveling. At the venting level: the introduction of SO3 reduces the surface tension of the melt, promoting the fusion and expulsion of bubbles. Simultaneously, strict control of organic matter content and optimization of the gas release rate ensure that bubbles fully escape before the glaze layer melts and seals, achieving "self-healing." At the crystal phase level: the firing cooling regime precisely induces the precipitation of submicron-sized zinc silicosite and strontium-containing microcrystals, whose refractive index matches that of glass, reducing light scattering. Simultaneously, the pinning effect of the microcrystals inhibits the propagation of micro-defects, improving the density of the glaze surface.

[0065] Example 2

[0066] A glossy ceramic tile includes a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer, the formula of which is the same as that of Example 1; the difference in its preparation method compared with the example is that the amount of high-transparency glaze applied is adjusted to 150g (400mm×600mm tray), and the rest is the same as the example.

[0067] The glossy ceramic tile prepared in Example 2 is as follows: Figure 3 As shown, the glaze surface smoothness is slightly improved, but the light transmittance does not change significantly, and the mold texture has a slightly stronger three-dimensional effect; its surface defects: the defect rate is 0.3%, which is close to that of Example 1. Its yield rate is 90%, slightly lower than that of Example 1. By comparing with Example 1, it can be found that increasing the glaze amount in Example 2 increases the glaze layer thickness, which can fill more fine unevenness during the leveling process, but excessive glaze is prone to accumulation at the edge of the mold, affecting the edge smoothness. This result indicates that the glaze amount needs to match the depth of the mold texture, and 135g is the optimal value.

[0068] Example 3

[0069] A glossy ceramic tile includes a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer, with the same formula as in Example 1; the difference in its preparation method compared to the example is that the firing temperature is 1250℃, the high-temperature holding time is extended to 20 minutes, and the other parameters remain unchanged.

[0070] The glossy ceramic tile prepared in Example 3 is as follows: Figure 4 As shown, the glaze surface smoothness is excellent, with no significant difference from Example 1; the surface defect rate is 0.3%, but the glaze transmittance is slightly reduced, exhibiting a slight milky appearance; the yield is 88%, with some blanks showing over-firing deformation. A comparison with Example 1 reveals that while extending the holding time promotes full glaze leveling and air release, excessive holding leads to excessive crystal growth in the glaze, with crystals exceeding submicron sizes, forming light scattering centers and resulting in decreased transmittance. Simultaneously, prolonged high-temperature exposure increases the risk of blank deformation, indicating that the holding time needs to be controlled within a reasonable range.

[0071] Comparative Example 1 (ZnO content decreased)

[0072] A ceramic tile includes a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer. The chemical composition of the high-transparency glaze layer, by mass percentage, includes: 57% SiO2, 13% Al2O3, 6% ZnO, 6% SrO, 8% CaO, 5% SO3, 3% B2O3, and 2% BaO. The remaining formulation composition is the same as in Example 1, and the preparation method is also the same as in Example 1.

[0073] The smoothness of the ceramic tile glaze obtained in Comparative Example 1: slight ripples are visible to the naked eye; the glaze layer is not fully leveled in the recessed areas of the mold texture, and there are local protrusions; surface defects: the rate of pinholes and prickly heat bubbles increased to 5.2%, and the glaze surface was obviously rough; yield: 65%. By comparing with Example 1, it can be found that the reduction of ZnO content leads to a significant increase in the high-temperature viscosity of the glaze, weakens the leveling ability, and fails to fully fill the mold texture during the firing cycle. At the same time, the surface tension of the melt increases, making it difficult for bubbles to fuse and escape, resulting in a large number of pinholes remaining. This verifies the core role of ZnO in reducing viscosity and promoting degassing.

[0074] Comparative Example 2 (SrO content decreased)

[0075] A ceramic tile includes a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer. The chemical composition of the high-transparency glaze layer, by mass percentage, includes: 57% SiO2, 13% Al2O3, 8% ZnO, 4% SrO, 8% CaO, 5% SO3, 3% B2O3, and 2% BaO. The remaining formulation composition is the same as in Example 1, and the preparation method is also the same as in Example 1.

[0076] The ceramic tiles prepared in Comparative Example 2 are as follows Figure 5As shown, its glaze surface smoothness is slightly better than that of Comparative Example 1, but the light transmittance is significantly reduced, and the glaze surface has a hazy texture; its surface defects: pinhole defect rate of 3.8%, still higher than that of the example group, and the glaze surface hardness is reduced; yield: 72%. By comparing with Example 1, it can be found that SrO is not only a strong flux, but also a high refractive index oxide. Its reduced content leads to a decrease in the refractive index of the glaze, an increase in light scattering, and a deterioration in light transmittance. At the same time, SrO participates in crystal phase formation. When the content is insufficient, the amount of microcrystal precipitation decreases, the ability to pin micro-defects weakens, resulting in an increase in pinhole residue, and a decrease in the density of the glaze surface structure and a decrease in hardness.

[0077] Comparative Example 3 (Increased Al2O3 content)

[0078] The product includes a base blank, a base glaze layer, a mold texture layer, and a high-transparency glaze layer. The chemical composition of the high-transparency glaze layer, by mass percentage, includes: 52% SiO2, 16% Al2O3, 8% ZnO, 6% SrO, 8% CaO, 5% SO3, 3% B2O3, and 2% BaO. The remaining formulation composition is the same as in Example 1, and the preparation method is also the same as in Example 1.

[0079] The ceramic tiles prepared in Comparative Example 3 are as follows Figure 6 As shown, the glaze surface smoothness is severely uneven, with the mold texture almost completely covered by the glaze layer, but the surface exhibits an orange peel-like defect; its surface defects include numerous pinholes and cavities, with a defect rate exceeding 8%, and the glaze completely loses its luster; the yield rate is 45%. A comparison with Example 1 reveals that the increased content of Al2O3 in the glaze skeleton significantly increases the high-temperature viscosity of the glaze, drastically reducing its fluidity. The glaze cannot flow smoothly on the mold surface, forming a wavy surface. Simultaneously, the high viscosity melt hinders bubble expulsion, resulting in numerous residual bubbles that rupture and form pinholes and cavities. This verifies the importance of precisely controlling the Al2O3 / SiO2 ratio; an excessively high Al2O3 proportion completely destroys the glaze's leveling and venting properties.

[0080] Comparative Example 4 (Firing temperature decreased)

[0081] A glossy ceramic tile includes a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer, with the same formula as in Example 1; the difference in its preparation method compared to the example is that the firing temperature during the heat preservation stage is 1200℃, while the other parameters remain unchanged.

[0082] The ceramic tiles prepared in Comparative Example 4 are as follows Figure 7As shown, the glaze surface smoothness is poor, the glaze layer is not fully melted, and the mold texture surface has a grainy feel; its surface defects include dense pinholes, a defect rate exceeding 10%, and a matte glaze surface; its yield is 35%. A comparison with Example 1 reveals that insufficient firing temperature resulted in the glaze not reaching a fully melted state, exhibiting high viscosity and poor fluidity, making it unable to level the mold texture. Simultaneously, insufficient gas release at low temperatures caused premature glaze sealing, trapping numerous air bubbles within the glaze layer, forming dense pinholes, and completely eliminating light transmittance. This indicates that 1250℃ is the critical temperature for ensuring glaze melting and venting.

[0083] Comparative Example 5 (Increased Heating Rate)

[0084] A glossy ceramic tile, comprising a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer, has the same formula as in Example 1; the difference in its preparation method compared to the example is that in the heating stage, the temperature is directly raised to 1250°C at a heating rate of 8°C / min, and the remaining steps are the same as in Example 1.

[0085] The ceramic tile prepared in Example 5 exhibited the following characteristics: glaze smoothness: localized ripples and glaze buildup at the edges of the mold texture; surface defects: pinhole defect rate of 2.5%, but minor cracks appeared on the glaze surface; yield: 78%. A comparison with Example 1 reveals that an excessively rapid heating rate leads to a sudden increase in thermal stress in the body and glaze layer, resulting in micro-cracks on the glaze surface. Simultaneously, rapid heating causes the glaze melting stage to occur earlier, overlapping the gas release and glaze leveling process. Some air bubbles are not expelled in time and are sealed, leading to pinhole residue. This indicates that a reasonable heating rate is crucial for balancing venting and thermal stress.

[0086] Comparative Example 6 (Increased Cooling Rate)

[0087] A glossy ceramic tile, comprising a base, a base glaze layer, a mold texture layer, and a high-transparency glaze layer, the formula of which is the same as that of Example 1; the preparation method of which differs from that of Example 1 is as follows: in the cooling stage, it is directly and rapidly cooled to 500°C at a cooling rate of 15°C / min, and finally cooled to room temperature with the furnace, the remaining steps are the same as those of Example 1.

[0088] The ceramic tile prepared in Example 6 had the following characteristics: glaze smoothness: acceptable, but significantly reduced glaze transmittance, resulting in a hazy appearance; surface defects: no obvious pinholes, but reduced glaze hardness and scratch resistance; yield: 85%. A comparison with Example 1 reveals that rapid cooling inhibited the uniform precipitation of submicron-sized microcrystals, increasing the proportion of the glass phase in the glaze. While this reduced the decrease in transmittance caused by excessive crystal growth, the lack of microcrystal pinning effect resulted in a loose glaze structure, reduced hardness, and increased residual stress within the glass phase, potentially leading to cracking during long-term use.

[0089] 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 glossy ceramic tile, characterized in that, The product includes a base blank, a base glaze layer, a mold texture layer, and a high-transparency glaze layer. The raw materials of the base glaze layer, by mass percentage, include: 25-30% quartz, 20-35% feldspar, 15-20% clay, 5-10% calcium carbonate, 3-5% zinc oxide, and 10-15% zircon sand. The chemical composition of the high-transparency glaze layer, by mass percentage, includes: 50-60% SiO2, 10-15% Al2O3, 7-9% ZnO, 5-8% SrO, 6-12% CaO, 3-6% SO3, 2-5% B2O3, and 1-3% BaO.

2. The glossy ceramic tile according to claim 1, characterized in that, The feldspar is one or both of sodium feldspar and potassium feldspar.

3. A method for preparing a glossy ceramic tile as described in claim 1 or 2, characterized in that, Including the following steps: The raw materials for the base glaze layer are fed into a ball mill according to the formula ratio, and deionized water is added for ball milling to obtain the base glaze slurry. The chemical composition of the high-transparency glaze is fed into a ball mill according to the formula ratio, and deionized water is added for ball milling to obtain a high-transparency glaze slurry. A base glaze slurry is applied to the surface of the body using a glazing process, and after drying, a base glaze layer is formed. A pre-designed mold texture is printed on the surface of the base glaze layer using inkjet printing to form a mold texture layer. A high-transparency glaze slurry is applied to the surface of the printed blank using a glazing process, and after drying, a high-transparency glaze layer is formed. The ceramic tile is obtained by firing the body that forms the base glaze layer and the high-transparency glaze layer.

4. The method for preparing glossy ceramic tiles according to claim 3, characterized in that, In the step of preparing the base glaze slurry, the raw materials of the base glaze layer and deionized water are added to a ball mill at a mass ratio of 1:0.

4. Alumina balls are used as the ball milling media. The ball mill speed is controlled at 250-350 r / min and the ball milling time is 6-8 h. The glaze slurry is then passed through a 325 mesh sieve and set aside for later use.

5. The method for preparing glossy ceramic tiles according to claim 4, characterized in that, The specific gravity of the base glaze slurry is 1.8-1.9 g / cm³. 3 .

6. The method for preparing glossy ceramic tiles according to claim 3, characterized in that, In the step of preparing high-transparency glaze slurry, the chemical composition of the base glaze layer and deionized water are added to a ball mill at a mass ratio of 1:0.

45. Alumina balls are used as the milling media. The ball mill speed is controlled at 300-400 r / min and the milling time is 8-10 h. The glaze slurry is then passed through a 325 mesh sieve for later use.

7. The method for preparing glossy ceramic tiles according to claim 6, characterized in that, The specific gravity of the high-transparency glaze slurry is 1.8-1.9 g / cm³. 3 .

8. The method for preparing glossy ceramic tiles according to claim 3, characterized in that, The firing process for the body forming the base glaze layer and the high-transparency glaze layer includes a heating stage, a holding stage, and a cooling stage. In the heating stage, the body is heated to 550-650℃ at a heating rate of 3℃ / min, then to 950-1050℃ at a heating rate of 5℃ / min, and then to 1230-1280℃ at a heating rate of 6℃ / min. In the holding stage, the body is held at 1230-1280℃ for 10-20 minutes. In the cooling stage, the body is first cooled to 750-850℃ at a cooling rate of 5℃ / min, then to 450-550℃ at a cooling rate of 3℃ / min, and finally cooled to room temperature in the furnace.

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