Pearl glaze for architectural ceramics as well as preparation method and application of pearl glaze

Abstract

The invention belongs to the technical field of glaze preparation, and particularly relates to pearl glaze for architectural ceramics as well as a preparation method and application of the pearl glaze. According to the invention, Si-Zr co-doped yttrium oxide directional crystallization, mesoporous alumina-vanadium boron tellurium glass composite particle compact glaze layer and self-repairing collaborative design are combined with medium-temperature segmented firing and flexible polishing process optimization; the pearl glaze with multiple effects of high pearl glossiness, skin friendliness, stain resistance, wear resistance, excellent blank adaptability, self-repairing durability and the like is prepared, a micro-damage self-repairing function is added, and the technical bottleneck of application of the existing pearl glaze to architectural ceramics is solved; according to the present invention, the raw materials are conventional, the process is simple, the obtained pearl glaze has characteristics of excellent mechanical property, excellent pollution resistance, excellent adaptability with the building ceramic green body, no deformation, no crack and no glaze layer peeling, the comprehensive performance of the product meets the building ceramic use requirement, the decoration effect and the touch are excellent, the method is suitable for the industrial mass production, and the significant technical advantage and the significant promotion value are provided.

Description

Technical Field

[0001] This invention belongs to the technical field of glaze preparation, specifically relating to a pearl glaze for building ceramics, its preparation method, and its application. Background Technology

[0002] Pearl glaze, with its warm, jade-like texture and soft luster, is widely used in ceramic decoration. Currently, pearl glaze is primarily focused on everyday ceramics, prepared using high-temperature sintering processes (typically 1280-1350℃). Its formula and process parameters are well-suited to the thin walls and low-temperature load-bearing characteristics of everyday ceramics, making it difficult to directly transfer to the field of architectural ceramics.

[0003] Building ceramics need to meet the requirements of high strength, wear resistance, and stain resistance. When attempting to apply pearl glaze from daily-use porcelain to building ceramics, there are many technical bottlenecks: First, the high-temperature sintering process is incompatible with the conventional production process of building ceramics, which can easily lead to deformation of the ceramic body and cracking of the glaze, increasing production costs. Second, the surface of building ceramics usually needs to be polished to improve its smoothness. After polishing, the pearl particles inside the glaze layer of existing pearl glaze are easily worn away, resulting in a significant reduction or even complete disappearance of the pearl luster. Third, the surface of existing pearl glaze often has slight bumps or a rough feel, and after polishing, it feels dry to the touch, failing to achieve the skin-friendly and delicate user experience of building ceramics. Summary of the Invention

[0004] To address the above-mentioned problems, the present invention aims to provide a pearl glaze for building ceramics, its preparation method, and its application.

[0005] The technical content of this invention is as follows: This invention provides a pearl glaze for building ceramics, wherein the components of the pearl glaze include fine albite, potassium feldspar, high alumina, calcined zinc, ultrafine quartz, talc, strontium carbonate, Si-Zr co-doped yttrium oxide, dolomite, and mesoporous alumina-vanadium boron tellurium glass composite particles.

[0006] By mass fraction, the fine albite accounts for 25-32%, potassium feldspar 18-25%, high alumina 8-12%, calcined zinc 5-8%, ultrafine quartz 6-10%, talc 4-6%, strontium carbonate 3-5%, Si-Zr co-doped yttrium oxide 0.8-1.5%, dolomite 2-4%, and mesoporous alumina-vanadium boron tellurium glass composite particles 1.2-2%.

[0007] The preparation of Si-Zr co-doped yttrium oxide according to the present invention includes the following steps: Yttrium salt, silicon salt, and zirconium salt are used as raw materials and mixed in a mass ratio of 100:(1~3):(0.5~2) to achieve Si doping of 1-2wt% and Zr doping of 0.5-1wt%. The mixture is dissolved in anhydrous ethanol at 3-5 times the total mass of the raw materials. Citric acid at 2-4wt% of the total mass of the raw materials is added as a chelating agent to adjust the pH value to 4-5. The mixture is stirred at 55-65℃ for 1.5-2.5h to form a sol. The sol is dried in an oven at 75-85℃ for 10-14h to obtain a dry gel. The dry gel is then placed in a muffle furnace and heated to 780-820℃ at a heating rate of 4-6℃ / min for 1.5-2.5h. After cooling, the mixture is ground to a particle size ≤3μm to obtain Si-Zr co-doped yttrium oxide powder. The yttrium salt includes one or more of yttrium nitrate (Y(NO3)2·6H2O) and yttrium chloride (YCl3·6H2O); The silicon salt includes one or more of tetraethyl orthosilicate (TEOS, industrial grade) and sodium silicate (Na2SiO3·9H2O); The zirconium salt includes one or more of zirconium oxychloride (ZrOCl2·8H2O) and zirconium nitrate (Zr(NO2)4·5H2O).

[0008] The preparation of the mesoporous alumina-vanadium boron tellurium glass composite particles includes the following steps: ① Preparation of mesoporous alumina support: Aluminum source and template agent are dissolved in deionized water at a mass ratio of 1:(0.15~0.25) in 20~25 times the total mass of raw materials. The mixture is stirred and hydrolyzed at 85~95℃ for 3~5h, aged at room temperature for 10~14h, and then filtered. The filter cake is washed with deionized water 3~4 times until neutral, dried at 105~115℃ for 5~7h, and then calcined at 520~580℃ for 2.5~3.5h to remove the template agent, thus obtaining mesoporous alumina support (pore size 50~80nm). The aluminum source includes one or more of aluminum isopropoxide and aluminum nitrate; The template agent includes one or more of polyethylene glycol (PEG-8000~12000) and hexadecyltrimethylammonium bromide (CTAB); ② Preparation of vanadium boron tellurium glass: V2O5, B2O3 and TeO2 are mixed evenly in a molar ratio of (28~32):(38~42):(28~32) and placed in a quartz crucible. The mixture is melted at 820~880℃ for 25~35 min, and stirred 2~3 times during the process to ensure uniform melting. Then, it is quickly placed in deionized water at room temperature and quenched to room temperature to obtain a transparent glass block. The block is then ground to a particle size ≤1μm. ③ Preparation of composite particles: Mesoporous alumina carrier and vanadium boron tellurium glass powder are mixed at a mass ratio of 60~70:30~40. Deionized water of 5~8% of the total mass of raw materials is added as a binder. The mixture is ground in a planetary ball mill at a low speed of 80~120 r / min for 25~35 min, and then dried at 105~115℃ for 3~5 h. The particle size is ground to ≤3μm to obtain the target composite particles.

[0009] The present invention also provides the application of the above-mentioned pearl glaze in architectural ceramics.

[0010] The present invention also provides a method for using the above-mentioned pearl glaze to prepare building ceramic products, comprising the following steps: 1) Ball milling: Weigh each raw material according to the above weight percentages. Among them, Si-Zr co-doped yttrium oxide needs to be activated by calcination at 800℃ for 2 hours in advance, and mesoporous alumina-vanadium boron tellurium glass composite particles need to be weighed in a dry environment to avoid moisture absorption; add 35-40% of the total weight of the raw materials with deionized water and put them into a ball mill for ball milling. The ball milling parameters were optimized as follows: ball-to-material ratio 3:1, rotation speed 220~260 r / min, and ball milling time 4-6 h, to ensure that the particle size of the glaze slurry after ball milling is ≤2μm and the particle size distribution is uniform. 2) Sieving and aging: The ball-milled glaze slurry is sieved through a 200-mesh sieve to remove impurities and unground particles. The slurry under the sieve is collected and placed in an aging tank and aged for 12-18 hours at 25-30℃ and 60-70% relative humidity. 3) Apply base glaze: Select a ceramic body (such as a porcelain tile or ceramic tile body), apply base glaze by spraying, and control the thickness of the base glaze to be 0.3~0.5mm. Then pre-bake at 80~100℃ for 30~40min to remove moisture from the base glaze layer and enhance the bonding force between the base glaze and the body. The base glaze uses a conventional transparent base glaze for architectural ceramics; 4) Inkjet printing: According to the decorative requirements, inkjet printing is performed on the surface of the pre-baked base glaze layer to form a preset pattern; 5) Apply pearl glaze: Apply the prepared pearl glaze slurry to the surface of the base glaze layer after inkjet printing using a glazing method, and control the thickness of the pearl glaze layer to be 0.2~0.3mm; The glazing speed was optimized to 8~12cm / s to ensure uniform glaze coverage; 6) Firing: The glazed ceramic blanks are fed into a roller kiln for firing. The firing process is a medium-temperature segmented firing: In the heating stage, the temperature is raised from room temperature to 800℃ at a rate of 5-8℃ / min; in the holding stage, the temperature is held at 800℃ for 30 minutes to promote the initial reaction of the glaze components; in the high-temperature stage, the temperature is raised from 800℃ to 1120-1180℃ at a rate of 3-5℃ / min, and held at this temperature for 40-60 minutes to allow the glaze to fully melt and crystallize to form a pearlescent structure; in the cooling stage, the temperature is lowered from the high temperature to room temperature at a rate of 4-6℃ / min to avoid cracking of the glaze surface due to excessively rapid cooling. 7) Polishing: After the fired building ceramics have cooled to room temperature, they are polished using a flexible polishing machine. The polishing parameters are: polishing head speed 150~180r / min, polishing pressure 0.1~0.15MPa, polishing time 2-3min. Flexible polishing can avoid damaging the pearlescent particles on the glaze surface and remove the fine protrusions on the glaze surface, forming a delicate and skin-friendly touch, thus obtaining building ceramic products with a pearl glaze effect.

[0011] The beneficial effects of this invention are as follows: This invention relates to a pearl glaze for building ceramics. Through the modification and compounding of Si-Zr co-doped yttrium oxide and mesoporous alumina-vanadium boron tellurium glass composite particles, combined with an optimized medium-temperature firing process, the resulting pearl glaze exhibits excellent decorative properties, a full and uniform pearly luster, high pearl gloss, and a delicate, skin-friendly surface. This solves the problems of insufficient gloss and rough texture found in existing pearl glazes. The pearl glaze of this invention also possesses excellent mechanical and anti-fouling properties, effectively resisting the adhesion of everyday pollutants, facilitating cleaning, and providing wear resistance and durability, thus extending the service life of building ceramics. Furthermore, this pearl glaze exhibits excellent compatibility with the building ceramic body, showing no deformation, cracking, or glaze peeling.

[0012] The preparation process of this invention, through the synergistic design of Si-Zr co-doped yttrium oxide directional crystallization, dense glaze layer of mesoporous alumina-vanadium boron tellurium glass composite particles, and self-healing, combined with optimized medium-temperature segmented firing and flexible polishing processes, produces a pearl glaze with multiple effects such as high pearl luster, skin-friendly, stain-resistant and wear-resistant, excellent body adaptability, and self-healing durability. It also adds a micro-damage self-healing function, solving the technical bottleneck of existing pearl glazes applied to building ceramics. The raw materials of this invention are conventional, the process is simple, the comprehensive performance of the product meets the requirements of building ceramics, the decorative effect and tactile feel are excellent, it is suitable for industrial mass production, and has significant technical advantages and promotional value. Detailed Implementation

[0013] The present invention will be further described in detail below through specific implementation examples. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of protection of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope of the appended claims.

[0014] Unless otherwise specified, all raw materials and reagents used in this invention are from the conventional market.

[0015] Example 1 A method for preparing pearl glaze for architectural ceramics 1) Preparation of Si-Zr co-doped yttrium oxide: Yttrium nitrate, tetraethyl orthosilicate, and zirconium oxychloride were mixed in a mass ratio of 100:1.6:0.95 and dissolved in anhydrous ethanol at 4 times the total mass of the raw materials. Citric acid at 3 wt% of the total mass of the raw materials was added as a chelating agent, and the pH was adjusted to 4.5 with dilute nitric acid. The mixture was stirred at 60°C for 2 hours to form a homogeneous sol. The sol was dried in an oven at 80°C for 12 hours to obtain a dry gel. Then, it was placed in a muffle furnace and heated to 800°C at a heating rate of 5°C / min for 2 hours. After naturally cooling to room temperature, it was ground with an air jet mill to a particle size ≤3μm to obtain Si-Zr co-doped yttrium oxide powder. Si-Zr co-doped yttrium oxide needs to be activated by calcination at 800℃ for 2 hours before use; 2) Preparation of mesoporous alumina-vanadium boron tellurium glass composite particles ① Preparation of mesoporous alumina carrier: Aluminum isopropoxide and polyethylene glycol were dissolved in deionized water at a mass ratio of 1:0.2 in 22 times the total mass of the raw materials. The mixture was stirred and hydrolyzed at 90℃ for 4 hours, aged at room temperature for 12 hours, and then filtered. The filter cake was washed three times with deionized water until neutral, dried at 110℃ for 6 hours, and then calcined at 550℃ for 3 hours to remove the template agent, thus obtaining the mesoporous alumina carrier. ② Preparation of vanadium boron tellurium glass: V2O5, B2O3 and TeO2 are mixed evenly in a molar ratio of 30:40:30 and placed in a quartz crucible. The mixture is melted at 850℃ for 30 min, and stirred once every 10 min during the process (stirred a total of 3 times) to ensure uniform melting. Then, it is quickly placed in deionized water at room temperature and quenched to room temperature to obtain a transparent glass block. The block is then ground with a planetary ball mill until the particle size is ≤1μm. ③ Preparation of composite particles: Mesoporous alumina carrier and vanadium boron tellurium glass powder are mixed at a mass ratio of 65:35. Deionized water of 6% of the total mass of raw materials is added as a binder. The mixture is ground at a low speed of 100 r / min for 30 min in a planetary ball mill, and then dried at 110℃ for 4 h. The particle size is ground to ≤3 μm to obtain mesoporous alumina-vanadium boron tellurium glass composite particles. Mesoporous alumina-vanadium boron tellurium glass composite particles need to be weighed in a dry environment to avoid moisture absorption; 3) Ball milling: Take 28% fine albite, 22% potassium feldspar, 10% high alumina, 6.5% calcined zinc, 8% ultrafine quartz, 5% talc, 4% strontium carbonate, 1.2% Si-Zr co-doped yttrium oxide, 3% dolomite, and 2.3% mesoporous alumina-vanadium boron tellurium glass composite particles, add 38% of the total weight of the raw materials in deionized water, ball-to-material ratio 3:1, speed 240 r / min, ball mill for 5 h to obtain glaze slurry with particle size ≤2μm; 4) Sieving and aging: Sieve through a 200-mesh sieve and age for 15 hours at 28℃ and 65% relative humidity; 5) Apply base glaze: Spray a base glaze onto the porcelain tile body to apply a thickness of 0.4 mm, and pre-bake at 85℃ for 35 minutes; 6) Inkjet printing: High-temperature ink for architectural ceramics is used for inkjet printing on the base glaze layer; 7) Apply pearl glaze: Apply pearl glaze by pouring, with a thickness of 0.25mm and a pouring speed of 10 cm / s; 8) Firing: Firing in a roller kiln, heating to 800℃ at a rate of 6℃ / min and holding for 30min; then heating to 1150℃ at a rate of 4℃ / min and holding for 50min; finally cooling to room temperature at a rate of 5℃ / min. 9) Polishing: Polish with a flexible polishing machine at a speed of 160 r / min, a pressure of 0.12MPa, and a time of 2.5min to obtain architectural ceramic products with a pearl glaze effect.

[0016] Example 2 A method for preparing pearl glaze for architectural ceramics 1) Preparation of Si-Zr co-doped yttrium oxide: Yttrium chloride, sodium silicate, and zirconium nitrate were mixed in a mass ratio of 100:2.2:1.3 and dissolved in anhydrous ethanol at 5 times the total mass of the raw materials. Citric acid at 4 wt% of the total mass of the raw materials was added as a chelating agent. The pH was adjusted to 5.0 with dilute ammonia. The mixture was stirred at 65°C for 2.5 h to form a uniform sol. The sol was dried in an oven at 85°C for 14 h to obtain a dry gel. Then, it was placed in a muffle furnace and heated to 820°C at a heating rate of 6°C / min for 2.5 h. After naturally cooling to room temperature, it was ground with an air jet mill to a particle size ≤3 μm to obtain Si-Zr co-doped yttrium oxide powder. 2) Preparation of mesoporous alumina-vanadium boron tellurium glass composite particles ① Preparation of mesoporous alumina carrier: Aluminum nitrate and hexadecyltrimethylammonium bromide were dissolved in deionized water at a mass ratio of 1:0.25 to 25 times the total mass of the raw materials. The mixture was stirred and hydrolyzed at 95°C for 5 hours, aged at room temperature for 14 hours, and then filtered. The filter cake was washed with deionized water 4 times until neutral, dried at 115°C for 7 hours, and then calcined at 580°C for 3.5 hours to remove the template agent, thus obtaining the mesoporous alumina carrier. ② Preparation of vanadium boron tellurium glass: V2O5, B2O3, and TeO2 were mixed evenly in a molar ratio of 32:42:32 and placed in a quartz crucible. The mixture was melted at 880℃ for 35 minutes, with stirring every 10 minutes (for a total of 3 times) to ensure uniform melting. The mixture was then quickly quenched in deionized water at room temperature to obtain a transparent glass block. The block was then ground with a planetary ball mill until the particle size was ≤1μm. ③ Preparation of composite particles: Mesoporous alumina carrier and vanadium boron tellurium glass powder are mixed at a mass ratio of 70:30. Deionized water of 8% of the total mass of raw materials is added as a binder. The mixture is ground at a low speed of 120 r / min for 35 min in a planetary ball mill, and then dried at 115℃ for 5 h. The particle size is ground to ≤3 μm to obtain mesoporous alumina-vanadium boron tellurium glass composite particles. 3) Ball milling: Take 25% fine albite, 25% potassium feldspar, 8% high alumina, 8% calcined zinc, 6% ultrafine quartz, 6% talc, 3% strontium carbonate, 1.5% Si-Zr co-doped yttrium oxide, 4% dolomite, and 1.5% mesoporous alumina-vanadium boron tellurium glass composite particles, add 35% of the total weight of the raw materials in deionized water, ball-to-material ratio 3:1, rotation speed 220 r / min, ball mill for 6 h to obtain glaze slurry with particle size ≤2μm; 4) Sieving and aging: Sieve through a 200-mesh sieve and age for 18 hours at 25℃ and 60% relative humidity; 5) Apply base glaze: Spray a base glaze onto the ceramic tile body to a thickness of 0.3mm, and pre-bake at 80℃ for 40 minutes; 6) Inkjet printing: High-temperature ink for architectural ceramics is used for inkjet printing on the base glaze layer; 7) Apply pearl glaze: Apply pearl glaze by pouring, with a thickness of 0.2mm and a pouring speed of 8cm / s; 8) Firing: Firing in a roller kiln, heating to 800℃ at a rate of 5℃ / min and holding for 30min; then heating to 1120℃ at a rate of 3℃ / min and holding for 60min; cooling to room temperature at a rate of 4℃ / min. 9) Polishing: Polish with a flexible polishing machine at a speed of 150 r / min, a pressure of 0.1 MPa, and a time of 3 min to obtain architectural ceramic products with a pearl glaze effect.

[0017] Example 3 A method for preparing pearl glaze for architectural ceramics 1) Preparation of Si-Zr co-doped yttrium oxide: Yttrium nitrate, tetraethyl orthosilicate, and zirconium oxychloride were mixed in a mass ratio of 100:1.1:0.6 and dissolved in anhydrous ethanol at 3 times the total mass of the raw materials. Citric acid at 2 wt% of the total mass of the raw materials was added as a chelating agent, and the pH was adjusted to 4.0 with dilute nitric acid. The mixture was stirred at 55°C for 1.5 h to form a homogeneous sol. The sol was dried in an oven at 75°C for 10 h to obtain a dry gel. Then, it was placed in a muffle furnace and heated to 780°C at a heating rate of 4°C / min and calcined for 1.5 h. After naturally cooling to room temperature, it was ground with an air jet mill to a particle size ≤3 μm to obtain Si-Zr co-doped yttrium oxide powder. 2) Preparation of mesoporous alumina-vanadium boron tellurium glass composite particles ① Preparation of mesoporous alumina carrier: Aluminum isopropoxide and polyethylene glycol were dissolved in deionized water at a mass ratio of 1:0.15, which was 20 times the total mass of the raw materials. The mixture was stirred and hydrolyzed at 85°C for 3 hours, aged at room temperature for 10 hours, and then filtered. The filter cake was washed three times with deionized water until neutral, dried at 105°C for 5 hours, and then calcined at 520°C for 2.5 hours to remove the template agent, thus obtaining the mesoporous alumina carrier. ② Preparation of vanadium boron tellurium glass: V2O5, B2O3, and TeO2 were mixed evenly in a molar ratio of 28:38:28 and placed in a quartz crucible. The mixture was melted at 820℃ for 25 min, with stirring every 10 min (for a total of 2 stirrings) to ensure uniform melting. The mixture was then quickly quenched in deionized water at room temperature to obtain a transparent glass block, which was then ground with a planetary ball mill until the particle size was ≤1μm. ③ Preparation of composite particles: Mesoporous alumina carrier and vanadium boron tellurium glass powder are mixed at a mass ratio of 60:40. 5% of the total mass of the raw materials is added as a binder. The mixture is ground at a low speed of 80 r / min for 25 min in a planetary ball mill. Then it is dried at 105℃ for 3 h and ground until the particle size is ≤3 μm to obtain mesoporous alumina-vanadium boron tellurium glass composite particles. 3) Ball milling: Take 32% fine albite, 18% potassium feldspar, 12% high alumina, 5% calcined zinc, 10% ultrafine quartz, 4% talc, 5% strontium carbonate, 0.8% Si-Zr co-doped yttrium oxide, 2% dolomite, and 1.2% mesoporous alumina-vanadium boron tellurium glass composite particles, add 40% of the total weight of the raw materials in deionized water, ball-to-material ratio 3:1, speed 260 r / min, ball mill for 4 h to obtain glaze slurry with particle size ≤2μm; 4) Sieving and aging: Sieve through a 200-mesh sieve and age for 12 hours at 30℃ and 70% relative humidity; 5) Apply base glaze: Spray a base glaze onto the porcelain tile body to apply a thickness of 0.5 mm, and pre-bake at 100℃ for 30 minutes; 6) Inkjet printing: High-temperature ink for architectural ceramics is used for inkjet printing on the base glaze layer; 7) Apply pearl glaze: Apply pearl glaze by pouring, with a thickness of 0.3mm and a pouring speed of 12cm / s; 8) Firing: Firing in a roller kiln, heating to 800℃ at a rate of 8℃ / min and holding for 30min; then heating to 1180℃ at a rate of 5℃ / min and holding for 40min; cooling to room temperature at a rate of 6℃ / min. 9) Polishing: Polish with a flexible polishing machine at a speed of 180 r / min, a pressure of 0.15 MPa, and a time of 2 min to obtain architectural ceramic products with a pearl glaze effect.

[0018] Comparative Example 1 As a control group for Example 1, in the preparation of the pearl glaze in Comparative Example 1, yttrium oxide was used instead of Si-Zr co-doped yttrium oxide, while other aspects remained unchanged.

[0019] Comparative Example 2 As a control group for Example 1, in the preparation of the pearl glaze in Comparative Example 2, ultrafine calcined alumina was used instead of mesoporous alumina-vanadium boron tellurium glass composite particles, while other aspects remained unchanged.

[0020] Comparative Example 3 As a control group for Example 1, the pearl glaze of Comparative Example 3 was prepared by high-temperature sintering at 1300℃ (holding for 40 min) during the firing stage, with other aspects remaining unchanged.

[0021] The pearl glazes prepared in the embodiments and comparative examples of the present invention were subjected to the following performance tests: 1. Pearl luster: A gloss meter was used, with a test angle of 60°. Five different points on the sample surface were selected for testing, and the average value was taken.

[0022] 2. Tactile roughness (Ra): Using a surface roughness meter, three test areas were selected, and each area was tested three times. The average value was taken.

[0023] 3. Mohs hardness: Using a Mohs hardness pen (grades 1-10), start with the lowest hardness grade and scratch the sample surface sequentially, recording the highest hardness grade that leaves no obvious scratches.

[0024] 4. Stain resistance rating: Refer to GB / T 3810.14-2016 "Test Methods for Ceramic Tiles Part 14: Determination of Stain Resistance", select three pollutants: coffee, soy sauce and red ink. After standing for 24 hours, wipe with water and neutral detergent. According to the degree of stain residue, it is divided into 1-5 levels (level 5 is the best, with no residue).

[0025] 5. Micro-scratch repair rate: Micro-scratches with a width of 3μm and a depth of 1μm were prepared on the sample surface using a scratch instrument. After soaking in 80℃ hot water for 30min, the change in scratch width was observed under a microscope. Repair rate = (width before repair - width after repair) / width before repair × 100%.

[0026] 6. Body fit: Observe whether the sample is deformed, cracked or peeled after firing. It is divided into three levels: excellent (no deformation, no cracks or peeling), qualified (slight deformation, no cracks or peeling), and unqualified (obvious deformation, cracks or peeling).

[0027] Table 1 Performance Tests As can be seen from Table 1, compared with the comparative example, the pearl glaze prepared in the embodiment of the present invention exhibits excellent comprehensive performance, with full pearl luster, delicate and skin-friendly texture, high hardness, good stain resistance, and excellent body adaptability, which can meet the needs of building ceramics in different scenarios.

[0028] In Comparative Example 1, when pure yttrium oxide was used to replace Si-Zr co-doped yttrium oxide, all properties decreased. This demonstrates that the Si-Zr co-doping modification of this invention can control the crystal structure of yttrium oxide, improve its directional crystallization efficiency, and make the pearlescent particles in the glaze layer more uniform in size and more densely distributed, thereby improving the fullness of the pearl luster. At the same time, Si and Zr doping elements can optimize the microstructure of the glaze layer, reduce the porosity of the glaze layer surface, and improve the density of the glaze layer, thereby reducing surface roughness and improving Mohs hardness and stain resistance.

[0029] In Comparative Example 2, after replacing the mesoporous alumina-vanadium boron tellurium glass composite particles with ordinary ultrafine calcined alumina, all properties decreased to varying degrees. This indicates that the mesoporous structure of the mesoporous alumina-vanadium boron tellurium glass composite particles of the present invention can effectively fill the pores inside the glaze layer, improve the density of the glaze layer, thereby reducing surface roughness, improving stain resistance and wear resistance; at the same time, its particle dispersion is better, which can ensure the smoothness of the glaze surface and improve the pearl luster.

[0030] The optimized medium-temperature firing process of this invention (up to 1150℃) is in line with the temperature tolerance of existing building ceramic bodies, which can avoid deformation and cracking of the body due to uneven thermal expansion, while ensuring a strong bond between the glaze and the body. In contrast, Comparative Example 3 uses high-temperature sintering at 1300℃ to replace the medium-temperature firing process, which causes the body to have unbalanced thermal expansion, resulting in deformation and glaze cracking, and cannot meet the needs of industrial production.

Claims

1. A pearl glaze for use in architectural ceramics, characterized in that, The pearl glaze comprises fine albite, potassium feldspar, high-alumina clay, calcined zinc, ultrafine quartz, talc, strontium carbonate, Si-Zr co-doped yttrium oxide, dolomite, and mesoporous alumina-vanadium boron tellurium glass composite particles.

2. The pearl glaze for building ceramics according to claim 1, characterized in that, By mass fraction, the fine albite accounts for 25-32%, potassium feldspar 18-25%, high alumina 8-12%, calcined zinc 5-8%, ultrafine quartz 6-10%, talc 4-6%, strontium carbonate 3-5%, Si-Zr co-doped yttrium oxide 0.8-1.5%, dolomite 2-4%, and mesoporous alumina-vanadium boron tellurium glass composite particles 1.2-2%.

3. The pearl glaze for architectural ceramics according to claim 1, characterized in that, The preparation of the Si-Zr co-doped yttrium oxide includes the following steps: Yttrium salt, silicon salt, and zirconium salt are used as raw materials and mixed in a mass ratio of 100:(1~3):(0.5~2) to achieve Si doping of 1-2wt% and Zr doping of 0.5-1wt%. The mixture is dissolved in anhydrous ethanol at 3-5 times the total mass of the raw materials. Citric acid at 2-4wt% of the total mass of the raw materials is added as a chelating agent to adjust the pH value to 4-5. The mixture is stirred at 55-65℃ for 1.5-2.5h to form a sol. The sol is dried in an oven at 75-85℃ for 10-14h to obtain a dry gel. The dry gel is then placed in a muffle furnace and heated to 780-820℃ at a heating rate of 4-6℃ / min for 1.5-2.5h. After cooling, the mixture is ground to a particle size ≤3μm to obtain Si-Zr co-doped yttrium oxide powder.

4. The pearl glaze for building ceramics according to claim 3, characterized in that, The yttrium salt includes one or more of yttrium nitrate and yttrium chloride; The silicon salt includes one or more of tetraethyl orthosilicate and sodium silicate; The zirconium salt includes one or more of zirconium oxychloride and zirconium nitrate.

5. The pearl glaze for building ceramics according to claim 1, characterized in that, The preparation of the mesoporous alumina-vanadium boron tellurium glass composite particles includes the following steps: ① Preparation of mesoporous alumina carrier: Aluminum source and template agent are dissolved in deionized water at a mass ratio of 1:(0.15~0.25) in 20~25 times the total mass of raw materials. The mixture is stirred and hydrolyzed at 85~95℃ for 3~5h, aged at room temperature for 10~14h, and then filtered. The filter cake is washed with deionized water until neutral, dried at 105~115℃ for 5~7h, and then calcined at 520~580℃ for 2.5~3.5h to remove the template agent, thus obtaining the mesoporous alumina carrier; The aluminum source includes one or more of aluminum isopropoxide and aluminum nitrate; The template agent includes one or more of polyethylene glycol and hexadecyltrimethylammonium bromide; ② Preparation of vanadium boron tellurium glass: V2O5, B2O3 and TeO2 are mixed evenly in a molar ratio of (28~32):(38~42):(28~32) and melted at 820~880℃ for 25~35min. Then, the mixture is rapidly quenched to room temperature to obtain a transparent glass block, which is then ground to a particle size ≤1μm. ③ Preparation of composite particles: Mesoporous alumina carrier and vanadium boron tellurium glass powder are mixed at a mass ratio of 60~70:30~40. Deionized water of 5~8% of the total mass of raw materials is added as a binder. The mixture is ground at a low speed of 80~120 r / min for 25~35 min, and then dried at 105~115℃ for 3~5 h. The particle size is ground to ≤3μm to obtain the target composite particles.

6. The application of the pearl glaze according to any one of claims 1 to 5 in architectural ceramics.

7. A method for preparing architectural ceramic products using the pearl glaze according to any one of claims 1 to 5, characterized in that, Includes the following steps: 1) Ball milling: Weigh each component as described in claim 2, add 35-40% of the total weight of the raw materials in deionized water, and put them into a ball mill for ball milling; 2) Sieving and aging: The glaze slurry after ball milling is sieved, and the slurry under the sieve is collected and put into the aging tank; 3) Apply base glaze: Select a ceramic blank, apply base glaze by spraying, and then pre-dry; 4) Inkjet; 5) Apply pearl glaze: Apply the pearl glaze slurry prepared in step 2) to the surface of the base glaze layer after inkjet printing using a glazing method, and control the thickness of the pearl glaze layer to be 0.2~0.3mm; 6) Firing: The glazed ceramic body is fired in stages at a medium temperature: heating stage, from room temperature to 800℃ at a heating rate of 5~8℃ / min; holding stage, holding at 800℃ for 30min; high temperature stage, from 800℃ to 1120~1180℃ at a heating rate of 3~5℃ / min, holding at this temperature for 40~60min; cooling stage, from high temperature to room temperature at a cooling rate of 4-6℃ / min. 7) Polishing: After the fired building ceramics have cooled to room temperature, they are polished to obtain building ceramic products with a pearl glaze effect.

8. The method for using the pearl glaze according to claim 7 to prepare architectural ceramic products, characterized in that, The ball milling speed is 220~260 r / min, and the ball milling time is 4-6 h.

9. The method for preparing architectural ceramic products using the pearl glaze according to claim 7, characterized in that, The aging conditions are as follows: aging for 12 to 18 hours at 25 to 30°C and 60 to 70% relative humidity.

10. The method for preparing architectural ceramic products using the pearl glaze according to claim 7, characterized in that, The polishing conditions are as follows: polishing head speed 150~180 r / min, polishing pressure 0.1~0.15 MPa, and polishing time 2-3 min.

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