An antibacterial easy-to-clean ceramic and a method for producing the same

Abstract

This application discloses an antibacterial and easy-to-clean ceramic and its preparation method. The antibacterial and easy-to-clean ceramic includes a glaze and a blank. The glaze includes 30-60 parts of potassium feldspar, 30-60 parts of sodium feldspar, 44-60 parts of phosphate, and 20-28 parts of a first antibacterial agent. The first antibacterial agent includes an active ingredient and a carrier, and the active ingredient includes zirconium oxide nanopowder and zinc oxide nanopowder. The blank includes 45-75 parts of rutile titanium dioxide, 50-60 parts of sodium alginate, 50-70 parts of composite fiber, 20-36 parts of surfactant, and 40-50 parts of a second antibacterial agent. The second antibacterial agent includes cuprous oxide. The composite fiber includes a first fiber body and a second fiber body, and the first fiber body includes TiB fiber. This application achieves excellent antibacterial properties and mechanical strength by adding zirconium oxide and zinc oxide nanoparticles with high antibacterial capabilities to the glaze and consolidating them with phosphates. Cuprous oxide is used as a second antibacterial active ingredient in the blank and combined with discontinuous TiB reinforcing fibers.

Description

Technical Field

[0001] This application relates to the technical field of ceramic materials, and in particular to an antibacterial and easy-to-clean ceramic and its preparation method. Background Technology

[0002] Ceramic materials are a class of solid materials made primarily of inorganic non-metallic substances through processes such as high-temperature sintering. Traditional ceramics mainly use natural minerals such as clay, quartz, and feldspar as raw materials. The firing temperature of traditional ceramics is generally between 1000℃ and 1300℃, and their products are widely used in building ceramics (such as ceramic tiles), daily-use ceramics (such as tableware and tea sets), and sanitary ware (such as toilets). However, traditional ceramics have some limitations, such as relatively low strength and hardness, high brittleness, limited functionality, and lack of antibacterial and easy-to-clean properties.

[0003] Modern ceramic materials are no longer limited to natural minerals; they increasingly utilize high-purity synthetic powders such as alumina, zirconium oxide, silicon carbide, and silicon nitride, as well as synthetic composite powders like synthetic bone meal and shell mineralization. These additives offer more uniform particle size distribution and higher purity, allowing for precise control of the ceramic's microstructure and specific properties, thus enabling the production of various types of functional ceramics to meet specific needs. Currently, there is significant market demand for antibacterial ceramics. Antibacterial ceramics achieve their antibacterial effects through physical and chemical methods, primarily including coating, impregnation, and mixed sintering. While coating and impregnation allow the antibacterial material to adhere to the ceramic surface, providing antibacterial properties, the effect is not long-lasting, and the material can easily leak out during use, potentially impacting human health.

[0004] Regarding the aforementioned technology, the applicant believes that existing antibacterial ceramics cannot possess long-lasting and highly effective antibacterial properties, and that the antibacterial active ingredients in ceramic materials cannot maintain good stability, resulting in poor antibacterial performance of ceramic materials. Summary of the Invention

[0005] In order to enable ceramic materials to obtain efficient antibacterial properties and long-lasting antibacterial stability, while also taking into account the characteristics of easy cleaning, this application provides an antibacterial and easy-to-clean ceramic and its preparation method.

[0006] In the first aspect, this application provides an antibacterial and easy-to-clean ceramic material, which adopts the following technical solution:

[0007] An antibacterial and easy-to-clean ceramic comprises a glaze and a body. By weight, the glaze comprises 50-90 parts calcite, 60-120 parts wollastonite, 30-60 parts potassium feldspar, 30-60 parts sodium feldspar, 44-60 parts phosphate, and 20-28 parts a first antibacterial agent. The first antibacterial agent comprises an active ingredient and a carrier, and the active ingredient comprises zirconium oxide nanopowder and zinc oxide nanopowder.

[0008] The raw material comprises 100-200 parts kaolin, 120-180 parts bentonite, 100-120 parts dolomite, 580-600 parts shell powder, 60-90 parts potassium feldspar, 50-70 parts sodium feldspar, 80-100 parts quartz, 45-75 parts rutile titanium dioxide, 50-60 parts sodium alginate, 50-70 parts composite fiber, 20-36 parts surfactant, and 40-50 parts second antibacterial agent; the second antibacterial agent includes cuprous oxide; the composite fiber comprises a first fiber body and a second fiber body, and the first fiber body includes TiB fiber.

[0009] By employing the above technical solution, the glaze components are loaded with zirconium oxide and zinc oxide nanoparticles onto a stable mesoporous material. This allows zinc ions to dissolve from the glaze layer, adsorb onto the cell membrane, and enter the bacterial cell. They bind to the sulfhydryl groups of proteins, causing the bacteria to lose their ability to divide and reproduce, ultimately leading to their death. Once the bacteria lose activity, the zinc ions are released again to repeatedly kill bacteria, thus maintaining a long-lasting antibacterial effect. Furthermore, the zirconium oxide nanomaterials significantly improve the flexural strength and fracture toughness of the ceramic glaze layer and work synergistically with zinc oxide for antibacterial action. By rationally occupying the pores of the mesoporous carrier, zinc oxide is evenly dispersed, resulting in higher mechanical strength for the first antibacterial agent composite particles without affecting the antibacterial effect, further ensuring the long-term antibacterial effect of the glaze layer. The addition of phosphates not only effectively fixes the nano-antibacterial agent powder but also forms a glassy thin layer on the glaze layer, improving its easy-to-clean properties.

[0010] For the billet composition, cuprous oxide is selected as the effective antibacterial component. When it comes into contact with bacteria in a humid environment, it is attracted by the negative charge on the cell membrane, allowing copper ions to penetrate the cell membrane and disrupt the internal electrical balance of the bacteria, causing microenvironmental disturbance and leading to their death. The surfactant effectively prevents the aggregation of cuprous oxide particles and induces their distribution along the fiber structure. TiB fibers in the composite fiber, as a discontinuous reinforced titanium-based composite material, possess excellent high specific strength, specific stiffness, and high-temperature resistance. They not only bond well with other inorganic components in the billet but also efficiently support the cuprous oxide through the fibrous structure of TiB whiskers, serving as the attachment framework for the antibacterial active substances within the billet system. Unlike other reinforcing fiber structures, the three-dimensional composite structure constructed by TiB and the antibacterial particles effectively reduces the significant non-uniform strain distribution between the matrix and fiber regions, resulting in more uniform dispersion of the antibacterial particles and higher antibacterial activity. Meanwhile, to cover up the color deviation caused by copper ions in the billet, rutile titanium dioxide is introduced to enhance the overall whiteness; and by introducing sodium alginate, the high temperature resistance of the billet system is improved, and copper ions can be chelated under high temperature conditions, thereby regulating the reactivity of copper ions and improving their stability, giving them a long-lasting antibacterial effect on a macroscopic level.

[0011] For the overall ceramic composition, a highly active and long-term stable antibacterial effect is achieved by combining the first antibacterial agent in the glaze layer and the second antibacterial agent in the body. At the same time, the potassium feldspar, sodium feldspar, and calcite in the glaze layer can act as a flux to lower the firing temperature of the glaze, promote the melting and flow of the glaze, and, in conjunction with the phosphate component, make the glaze layer smoother and flatter, reduce the adsorption and residue of stains, and thus improve its easy-to-clean performance.

[0012] Preferably, the carrier comprises one or more of activated carbon, multi-walled carbon nanotubes, and silica.

[0013] By adopting the above technical solutions and selecting suitable mesoporous materials to effectively load antibacterial nanoparticles, the high specific surface area and porosity of the mesoporous materials can provide a large number of uniform active loading sites for the antibacterial nanoparticles, preventing the agglomeration of zirconium oxide and zinc oxide nanoparticles, thus achieving high dispersion and better antibacterial effect. It can also mitigate the adverse effects of other ceramic matrix materials on the antibacterial effect of the active ingredients. Specifically, activated carbon (carbon molecular sieve), as a functional carbon adsorbent, has a large specific surface area, regular pore structure, and strong adsorption properties, enabling it to effectively adsorb zirconium oxide and zinc oxide nanoparticles. Multi-walled carbon nanotubes, as a one-dimensional quantum material, have a compact hexagonal structure and exhibit significant chemical inertness, allowing them to form layered structures with different loadings for different antibacterial nanoparticles and providing high mechanical strength. Silica, mainly hydrated amorphous silica, possesses high temperature resistance, large specific surface area, resistance to thermal decomposition, chemical stability, and good dispersibility, thus serving as an effective carrier while also reinforcing the ceramic glaze layer.

[0014] Preferably, the zirconium oxide nanoparticles have a particle size of 50-500 nm, and / or the zinc oxide has a particle size of 50-100 nm.

[0015] By adopting the above technical solution, on the one hand, zirconia nanopowder and zinc oxide nanopowder are jointly added to the ceramic glaze layer for composite powder modification. Both have strong antibacterial and bacteriostatic effects. Zinc ions in zinc oxide can combine with negatively charged groups on the surface of bacterial cells, destroying the microstructure and biological function of the cell membrane, causing leakage of cell contents, and interfering with the bacterial enzyme system, inhibiting its growth and reproduction, thereby achieving a bactericidal effect. Since zirconia will undergo volume expansion under specific conditions (martensitic phase transformation), and zinc oxide can act as a stabilizer, forming a solid solution with zirconia after high-temperature sintering, effectively avoiding the volume effect and obtaining high high-temperature stability. After returning to room temperature, both can still maintain tetragonal or cubic phase stability, thus enabling the ceramic glaze layer to maintain a long-lasting and synergistic antibacterial effect. On the other hand, selecting zirconia and zinc oxide nanopowders with specific particle size ranges can have special surface effects and synergistically cooperate with the carrier. Furthermore, due to the high atomic diffusion coefficient and unsaturated atomic coordination of the interfacial atomic regions of nanoparticles, both have higher antibacterial activity in the glaze system. Meanwhile, zirconium oxide and zinc oxide powders within this range have smaller particle sizes and are evenly distributed in the ceramic glaze, resulting in weaker light scattering. This allows the glaze to maintain good transparency and meet higher requirements for dyeing processes.

[0016] Preferably, the phosphate includes one or more of ammonium dihydrogen phosphate and diammonium hydrogen phosphate.

[0017] By adopting the above technical solution, on the one hand, both ammonium dihydrogen phosphate and diammonium hydrogen phosphate have low melting points and high surface tension, which can work with the potassium feldspar and sodium feldspar components in the glaze to form a uniform glassy film on the surface, making it difficult for stains to adhere and easier to clean; on the other hand, when ammonium dihydrogen phosphate and diammonium hydrogen phosphate react with the antibacterial agent components in advance, they form a glassy or mineral-like phase, and form a stable structure around the metal ions (such as zinc ions) in the system, thereby greatly improving the stability of the antibacterial agent components on the glaze surface.

[0018] Preferably, the second fiber body comprises one or more of silicon carbide fibers and alumina fibers.

[0019] By adopting the above technical solution, on the one hand, silicon carbide fibers and alumina fibers can be incorporated into the ceramic body as reinforcing fibers to significantly enhance toughness. When the ceramic is subjected to external force, the second fiber body can hinder the propagation of cracks and absorb energy through the bridging and pull-out effects of the fiber structure, thereby improving the overall strength of the ceramic material. On the other hand, silicon carbide fibers and alumina fibers both have good high-temperature resistance, which can help the active ingredients in the second antibacterial agent maintain a stable inherent structure under high-temperature conditions and reduce the thermal expansion coefficient of the ceramic matrix, thereby improving the thermal stability of the ceramic material and further preventing high temperature from damaging the antibacterial structure in the body.

[0020] Preferably, the mass ratio of the first fiber to the second fiber is 1:(0.2-0.5).

[0021] By adopting the above technical solution, setting a specific mass ratio range between the first and second fibers within the billet system ensures that the uniform dispersion and distribution of antibacterial active substances by the first fibers and the regulation of their antibacterial activity are not affected, nor is the effective regulation of the mechanical properties and high-temperature resistance of the billet by the second fibers affected. When the mass ratio range between the first and second fibers is unreasonable, not only can the above technical effects not be achieved, but the fiber structure within the billet is also prone to forming a disordered and irregular structure, hindering the function of other functional components and adversely affecting the structural stability of the billet.

[0022] Preferably, the surfactant comprises one or more of polyvinylpyrrolidone (PVP) and hexadecyltrimethylammonium bromide (CTAB).

[0023] By employing the above technical solution, polyvinylpyrrolidone (PVP) and hexadecyltrimethylammonium bromide (CTAB) are used as surfactants. The carbonyl or nitrogen atoms in the PVP molecule, or the amphiphilic structure of CTAB, can adsorb and bind to the surface of cuprous oxide particles, the antibacterial active ingredient, forming a protective film on their surface. This prevents the cuprous oxide particles from agglomerating or precipitating due to collisions, static electricity, etc., ensuring a stable dispersion within the preform system and guaranteeing a long-lasting antibacterial effect after the preform is formed. Simultaneously, both PVP and CTAB can guide the forming shape of cuprous oxide within the preform system, influencing the extension and growth of cuprous oxide particles along the fibrous structure (especially TiB fibers), thereby forming a uniform antibacterial agent distribution structure within the preform to achieve a uniform and stable antibacterial effect.

[0024] Secondly, this application provides a method for preparing an antibacterial and easy-to-clean ceramic, comprising the following steps:

[0025] S1. Glaze preparation: Calcite, wollastonite, potassium feldspar and sodium feldspar are ball-milled and mixed evenly to obtain glaze powder. The active ingredients in the first antibacterial agent are loaded onto the carrier through vacuum permeation. The first antibacterial agent, phosphate and water are added to the glaze powder. The temperature is raised to 55-65℃ and stirred at high speed of 1000-1100r / min for 1-2h. The mixture is then allowed to stand to obtain glaze slurry.

[0026] S2. Green body preparation: Kaolin, bentonite, dolomite, shell powder, potassium feldspar, sodium feldspar and quartz are mixed evenly and the green body powder is obtained by wet ball milling; the composite fiber is pretreated and surfactant, rutile titanium dioxide, sodium alginate and second antibacterial agent are added and dissolved and mixed, then the green body powder and water are added and stirred, heated to 90-100℃, and pressed into shape to obtain the green body;

[0027] S3. Preliminary firing: Let the green body stand naturally for 20-24 hours, control the moisture content inside the green body to 1%-6%, then calcine the green body at 1200-1400℃ for 12-24 hours, and cool it naturally to obtain the raw green body.

[0028] S4. Glazing: The glaze is sprayed onto the surface of the unglazed body to obtain a ceramic preliminary product;

[0029] S5. Secondary firing: The initial ceramic product is calcined at 1150-1350℃ for 6-12 hours and then naturally cooled to obtain the finished ceramic product.

[0030] By adopting the above technical solution, the glaze slurry preparation process employs a step-by-step method to first prepare the glaze powder, and then introduces the first antibacterial agent and other functional materials. This ensures the subsequent antibacterial effect and easy-to-clean properties of the glaze layer, preventing microstructural damage or deactivation in the preceding steps. Furthermore, the first antibacterial agent is prepared using a vacuum infiltration method. The vacuum environment allows antibacterial nanoparticles to penetrate into the mesoporous carrier under pressure difference to achieve effective loading and mixing, forming a stable and high-load composite antibacterial structure. The green body is then prepared using the same step-by-step method to ensure the stable functioning of the second antibacterial agent and other functional materials. Finally, the glaze slurry is uniformly coated onto the surface of the green body using a spray glazing method, combined with high-temperature sintering to produce a ceramic product that combines antibacterial efficacy and easy cleaning. This preparation method is stable and controllable, enabling industrial-scale production and processing.

[0031] Preferably, in step S2, the pretreatment of the composite fiber includes cutting the first fiber body and the second fiber body into short fibers, wherein the aspect ratio of the first fiber body is 20-40, and / or the length of the second fiber body is 0.1-0.5 mm.

[0032] By employing the above technical solution, both the first and second fibers are mechanically cut into short fiber forms, which improves the uniformity of fiber material distribution within the ceramic body without affecting the individual functions of the fibers. Setting the aspect ratio of the TiB fibers in the first fiber body within a specific range ensures their enhanced effect on regulating the activity of antibacterial particles. Furthermore, setting the length of the silicon carbide / alumina fibers in the second fiber body within a specific range improves their compatibility and bonding strength within the body system while maintaining a reinforcing effect.

[0033] Preferably, in step S2, the blank is obtained by isostatic pressing, and the isostatic pressing pressure is 180-260 MPa.

[0034] By employing the above-mentioned technical solution, the green body is prepared using isostatic pressing, and by controlling the appropriate isostatic pressing pressure, pressure is transmitted through a liquid or gas medium to ensure that the green body is subjected to uniform pressure in all directions. This avoids problems such as uneven green body density and deformation caused by uneven pressure. Furthermore, isostatic pressing effectively eliminates the voids between the antibacterial particles and the fibrous structure, significantly improving the density and strength of the green body and reducing shrinkage and deformation during subsequent high-temperature sintering, thereby improving the dimensional accuracy and production quality of the finished ceramic product. Simultaneously, other forming methods such as rolling, slip casting, or other molding methods can also be used to achieve good green body forming results.

[0035] In summary, this application has the following beneficial effects:

[0036] 1. This application selects cuprous oxide as the effective antibacterial component in the billet composition. When cuprous oxide comes into contact with bacteria in a humid environment, it is attracted by the negative charge on the cell membrane, allowing copper ions to penetrate the cell membrane and disrupt the internal electrical balance of the bacteria, causing microenvironmental disorder and leading to their death. The surfactant effectively prevents the aggregation of cuprous oxide particles and induces their distribution along the fiber structure. The TiB fiber in the composite fiber, as a discontinuous reinforced titanium-based composite material, possesses excellent high specific strength, specific stiffness, and high-temperature resistance. It not only combines well with other inorganic components in the billet but also efficiently supports the cuprous oxide through the fiber-like structure of TiB whiskers, serving as a support framework for the antibacterial active substance within the billet system. Unlike other reinforcing fiber structures, the three-dimensional composite structure constructed by TiB and the antibacterial particles effectively reduces the significant non-uniform strain distribution between the matrix and fiber regions, resulting in more uniform dispersion of the antibacterial particles and higher antibacterial activity. Meanwhile, to cover up the color deviation caused by copper ions in the billet, rutile titanium dioxide is introduced to enhance the overall whiteness; and by introducing sodium alginate, the high temperature resistance of the billet system is improved, and copper ions can be chelated under high temperature conditions, thereby regulating the reactivity of copper ions and improving their stability, giving them a long-lasting antibacterial effect on a macroscopic level.

[0037] 2. This application adds phosphate components to the glaze. On the one hand, both ammonium dihydrogen phosphate and diammonium hydrogen phosphate have low melting points and high surface tension, which can work with potassium feldspar and sodium feldspar components in the glaze to form a uniform glassy film on the surface, making it difficult for stains to adhere and easier to clean. On the other hand, when ammonium dihydrogen phosphate and diammonium hydrogen phosphate react with the antibacterial agent components in advance, they form a glassy or mineral-like phase and form a stable structure around the metal ions (such as zinc ions) in the system, thereby greatly improving the stability of the antibacterial agent components on the glaze surface.

[0038] 3. This application uses polyvinylpyrrolidone (PVP) and hexadecyltrimethylammonium bromide (CTAB) as surfactants. The carbonyl or nitrogen atoms in the PVP molecule, or the amphiphilic structure of CTAB, can adsorb and bind to the surface of the antibacterial active ingredient, cuprous oxide particles, forming a protective film on their surface. This prevents the cuprous oxide particles from agglomerating or precipitating due to collisions, static electricity, etc., ensuring a stable dispersion within the preform system and guaranteeing a long-lasting antibacterial effect after the preform is formed. Simultaneously, both PVP and CTAB can guide the forming shape of cuprous oxide within the preform system, influencing the extension and growth of cuprous oxide particles along the fibrous structure (especially TiB fibers), thereby forming a uniform antibacterial agent distribution structure within the preform to achieve a uniform and stable antibacterial effect. Detailed Implementation

[0039] This application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0041] In this application, terms such as "further," "even more," "particularly," "for example," "like," "example," and "exemplary" are used for descriptive purposes to indicate that different technical solutions preceding and following each other are related in terms of their coverage, but should not be construed as limiting the preceding technical solution or restricting the scope of protection of this application. In this application, unless otherwise specified, A (e.g., B) indicates that B is a non-limiting example of A, and it can be understood that A is not limited to B.

[0042] In this application, the technical features or solutions described in open-ended language include both closed-ended technical features or solutions consisting of the listed contents and open-ended technical features or solutions that include the listed contents.

[0043] In this application, the exemplary descriptions such as "in some implementations (or embodiments)" and "in one implementation (or embodiment)" may cover, but are not limited to, the following meanings: these solutions can be combined with other solutions in a suitable manner to form new technical solutions.

[0044] In this application, where the method flow involves multiple steps, unless otherwise explicitly stated herein, there is no strict order restriction on the execution of these steps; they can be executed in any order other than those described. Moreover, any step may include multiple sub-steps or multiple stages, which are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or simultaneously with other steps or parts of the sub-steps or stages of other steps.

[0045] The raw materials used in the examples and comparative examples are all commercially available.

[0046] The first antibacterial agent comprises an active ingredient with antibacterial efficacy and a carrier with mesoporous material properties. The active ingredient is a mixture of zirconia nanoparticles and zinc oxide nanoparticles, with the zirconia nanoparticles having a particle size range of 50-500 nm, preferably 50-300 nm; and the zinc oxide nanoparticles having a particle size range of 50-100 nm, preferably 50-60 nm. When the mass ratio of zirconia nanoparticles to zinc oxide nanoparticles is 1:(1.80-3.40), the effective component of zinc oxide is kept slightly higher than that of zirconia to ensure antibacterial performance, especially against Staphylococcus aureus and Escherichia coli.

[0047] The second antibacterial agent needs to work in conjunction with the composite fibers on the preform. The active ingredient with antibacterial effect in the second antibacterial agent is cuprous oxide. There are no specific restrictions on the particle size of the cuprous oxide; it is preferably prepared using a solid-state method, such as reducing copper oxide to cuprous oxide with copper powder as a reducing agent under high temperature conditions; or annealing and oxidizing copper powder in an aerobic environment to obtain cuprous oxide. The prepared cuprous oxide material is then mechanically processed to precisely control its purity, composition, structure, and morphology.

[0048] The TiB fiber, the first fibrous component in the composite fiber, is prepared using Ti and TiB2 powders. The preferred particle size of the Ti powder is 100-200 μm, while the preferred particle size of the TiB2 powder is 5-10 μm. The Ti and TiB2 powders are mixed using a ball milling process at 100 r / min for 4 hours. A mold consisting of hundreds of tubes and a substrate is then constructed to control the distribution of the composite powder. The mixed powder is filled into an array of tubes, while pure Ti powder is placed in the voids outside the tube walls, resulting in a confined array distribution of the mixed powder, exhibiting a fiber-like structure. The powder-filled fiber-like structure mold is then placed in a steel refrigerant press for cold pressing at a pressure of 300-400 MPa for 5 minutes. Finally, vacuum hot pressing sintering is carried out at 1500K for 1 hour, with a pressure of 40MPa and a vacuum degree maintained at 0.01Pa; and the first fibrous TiB fiber is obtained by hot extrusion (extrusion ratio of 14:1).

[0049] Preparation Example

[0050] 1. Preparation of glaze slurry

[0051] Preparation Example 1-1, the method for preparing ceramic glaze slurry, adopts the following steps:

[0052] (1) 70 kg of calcite, 90 kg of wollastonite, 45 kg of potassium feldspar and 45 kg of sodium feldspar were ball-milled and mixed evenly to obtain glaze powder;

[0053] (2) Add 24 kg of the first antibacterial agent, 52 kg of phosphate and 4.6 L of deionized water to the glaze powder, heat to 60 °C, and stir at 1100 r / min for 1.5 h, and let stand to obtain the glaze slurry.

[0054] Among them, for the first antibacterial agent, the mass ratio of zirconium oxide nanoparticles to zinc oxide nanoparticles is 1:2.60, the carrier is multi-walled carbon nanotubes, and the phosphate is ammonium dihydrogen phosphate.

[0055] Preparation Examples 1-2, the method for preparing ceramic glaze slurry, adopts the following steps:

[0056] (1) 90 kg of calcite, 120 kg of wollastonite, 60 kg of potassium feldspar and 60 kg of sodium feldspar were ball-milled and mixed evenly to obtain glaze powder;

[0057] (2) Add 28 kg of the first antibacterial agent, 60 kg of phosphate and 5.4 L of deionized water to the glaze powder, heat to 65 °C, and stir at 1100 r / min for 2 h. Let stand to obtain the glaze slurry.

[0058] Among them, for the first antibacterial agent, the mass ratio of zirconium oxide nanoparticles to zinc oxide nanoparticles is 1:2.60, the carrier is multi-walled carbon nanotubes, and the phosphate is ammonium dihydrogen phosphate.

[0059] Preparation Examples 1-3, the method for preparing ceramic glaze slurry, adopts the following steps:

[0060] (1) 50 kg of calcite, 60 kg of wollastonite, 30 kg of potassium feldspar and 30 kg of sodium feldspar were ball-milled and mixed evenly to obtain glaze powder;

[0061] (2) Add 20kg of the first antibacterial agent, 44kg of phosphate and 3.8L of deionized water to the glaze powder, heat to 55℃, and stir at 1000r / min for 1h. Let stand to obtain the glaze slurry.

[0062] Among them, for the first antibacterial agent, the mass ratio of zirconium oxide nanoparticles to zinc oxide nanoparticles is 1:2.60, the carrier is multi-walled carbon nanotubes, and the phosphate is ammonium dihydrogen phosphate.

[0063] Preparation Examples 1-4, the method for preparing ceramic glaze slurry, differs from Preparation Example 1-1 in that the carrier in the first antibacterial agent is activated carbon.

[0064] Preparation Examples 1-5, the method for preparing ceramic glaze slurry, differs from Preparation Example 1-1 in that the carrier in the first antibacterial agent is selected as silica.

[0065] Preparation Examples 1-6, the method for preparing ceramic glaze slurry, differs from Preparation Example 1-1 in that the phosphate used is diammonium hydrogen phosphate.

[0066] Preparation Examples 1-7, the method for preparing ceramic glaze slurry, differs from Preparation Example 1-1 in that the mass ratio of zirconium oxide nanopowder to zinc oxide nanopowder in the first antibacterial agent is 1:3.40.

[0067] Preparation Examples 1-8, the method for preparing ceramic glaze slurry, differs from Preparation Example 1-1 in that the mass ratio of zirconium oxide nanopowder to zinc oxide nanopowder in the first antibacterial agent is 1:1.80.

[0068] 2. Preparation of the green body

[0069] Preparation Example 2-1, the method for preparing the ceramic green body, adopts the following steps:

[0070] (1) Mix 150kg kaolin, 150kg bentonite, 110kg dolomite, 590kg shell powder, 75kg potassium feldspar, 60kg sodium feldspar and 90kg quartz evenly, and then obtain the green body powder by wet ball milling.

[0071] (2) Pre-treat 60kg of composite fiber, add 28kg of surfactant, 60kg of rutile titanium dioxide, 55kg of sodium alginate and 45kg of second antibacterial agent to dissolve and mix, then add the green body powder and 6.8L of water and stir to mix, heat to 95℃, and press to obtain the green body by isostatic pressing.

[0072] In the composite fiber, the second fiber body is made of silicon carbide fiber, and the mass ratio of the first fiber body to the second fiber body is 1:0.35; the surfactant is polyvinylpyrrolidone (PVP); and the isostatic pressure is 220 MPa.

[0073] Preparation Example 2-2, the method for preparing ceramic green bodies, adopts the following steps:

[0074] (1) Mix 200kg kaolin, 180kg bentonite, 120kg dolomite, 600kg shell powder, 90kg potassium feldspar, 70kg sodium feldspar and 100kg quartz evenly, and then obtain the green body powder by wet ball milling.

[0075] (2) 70kg of composite fiber is pretreated and 36kg of surfactant, 75kg of rutile titanium dioxide, 60kg of sodium alginate and 50kg of second antibacterial agent are added and dissolved and mixed. Then, the green body powder and 7.4L of water are added and stirred and mixed. The temperature is raised to 100℃ and isostatically pressed to obtain the green body.

[0076] In the composite fiber, the second fiber body is made of silicon carbide fiber, and the mass ratio of the first fiber body to the second fiber body is 1:0.35; the surfactant is polyvinylpyrrolidone (PVP); and the isostatic pressure is 220 MPa.

[0077] Preparation Example 2-3, the method for preparing ceramic green bodies, adopts the following steps:

[0078] (1) Mix 100kg kaolin, 120kg bentonite, 100kg dolomite, 580kg shell powder, 60kg potassium feldspar, 50kg sodium feldspar and 80kg quartz evenly, and then obtain the green body powder by wet ball milling.

[0079] (2) 50kg of composite fiber is pretreated and 20kg of surfactant, 45kg of rutile titanium dioxide, 50kg of sodium alginate and 40kg of second antibacterial agent are added and dissolved and mixed. Then, the green body powder and 6.2L of water are added and stirred and mixed. The temperature is raised to 90℃ and isostatically pressed to obtain the green body.

[0080] In the composite fiber, the second fiber body is made of silicon carbide fiber, and the mass ratio of the first fiber body to the second fiber body is 1:0.35; the surfactant is polyvinylpyrrolidone (PVP); and the isostatic pressure is 220 MPa.

[0081] Preparation Example 2-4, the method for preparing the ceramic green body differs from that in Preparation Example 2-1 in that the second fiber body is selected as alumina fiber.

[0082] Preparation Example 2-5, the method for preparing the ceramic body differs from that in Preparation Example 2-1 in that the mass ratio of the first fiber to the second fiber is 1:0.5.

[0083] Preparation Example 2-6, the method for preparing the ceramic green body differs from that in Preparation Example 2-1 in that the mass ratio of the first fiber to the second fiber is 1:0.2.

[0084] Preparation Example 2-7, the method for preparing the ceramic green body differs from that in Preparation Example 2-1 in that the surfactant used is hexadecyltrimethylammonium bromide (CTAB).

[0085] Preparation Example 2-8: The method for preparing the ceramic green body differs from that in Preparation Example 2-1 in that the isostatic pressure is 260 MPa.

[0086] Preparation Example 2-9: The method for preparing the ceramic green body differs from that in Preparation Example 2-1 in that the isostatic pressure is 180 MPa.

[0087] Example

[0088] Example 1: An antibacterial and easy-to-clean ceramic, the preparation method of which includes the following steps:

[0089] (1) The blank prepared in Example 2-1 was left to stand naturally for 22 hours, the moisture content inside the blank was controlled to be 4%, and then the blank was calcined at 1300℃ for 18 hours and cooled naturally to obtain the raw blank.

[0090] (2) The glaze slurry prepared in Preparation Example 1-1 is sprayed onto the surface of the unglazed body to obtain a ceramic prototype;

[0091] (3) The ceramic raw material was calcined at 1250℃ for 9 hours and then cooled naturally to obtain the finished ceramic product.

[0092] Example 2: An antibacterial and easy-to-clean ceramic, the preparation method of which includes the following steps:

[0093] (1) The blank prepared in Example 2-1 was left to stand naturally for 24 hours, the moisture content inside the blank was controlled at 1%, and then the blank was calcined at 1400℃ for 24 hours and cooled naturally to obtain a raw blank.

[0094] (2) The glaze slurry prepared in Preparation Example 1-1 is sprayed onto the surface of the unglazed body to obtain a ceramic prototype;

[0095] (3) The ceramic sample was calcined at 1350℃ for 12 hours and then cooled naturally to obtain the finished ceramic product.

[0096] Example 3: An antibacterial and easy-to-clean ceramic, the preparation method of which includes the following steps:

[0097] (1) The blank prepared in Example 2-1 was left to stand naturally for 20 hours, the moisture content inside the blank was controlled to be 6%, and then the blank was calcined at 1200℃ for 12 hours and cooled naturally to obtain the raw blank.

[0098] (2) The glaze slurry prepared in Preparation Example 1-1 is sprayed onto the surface of the unglazed body to obtain a ceramic prototype;

[0099] (3) The ceramic raw material was calcined at 1150℃ for 6 hours and then cooled naturally to obtain the finished ceramic product.

[0100] Example 4, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 1-2.

[0101] Example 5, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 1-3.

[0102] Example 6, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 1-4.

[0103] Example 7, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 1-5.

[0104] Example 8, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 1-6.

[0105] Example 9, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 1-7.

[0106] Example 10, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 1-8.

[0107] Example 11, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the green body is derived from Preparation Example 2-2.

[0108] Example 12, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 2-3.

[0109] Example 13, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 2-4.

[0110] Example 14, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 2-5.

[0111] Example 15, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 2-6.

[0112] Example 16, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 2-7.

[0113] Example 17, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 2-8.

[0114] Example 18, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the glaze slurry is derived from Preparation Examples 2-9.

[0115] Comparative Example

[0116] Comparative Example 1 is an antibacterial and easy-to-clean ceramic, which differs from Example 1 in that the active ingredients of the first antibacterial agent in the glaze, zirconium oxide powder and zinc oxide powder, are not nano-sized powders.

[0117] Comparative Example 2, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the mass ratio of zirconium oxide nanoparticles to zinc oxide nanoparticles in the first antibacterial agent of the glaze is 2:0.8.

[0118] Comparative Example 3 is an antibacterial and easy-to-clean ceramic, which differs from Example 1 in that the carrier of the first antibacterial agent in the glaze is replaced by an equal amount of dense and smooth glass particles.

[0119] Comparative Example 4 is an antibacterial and easy-to-clean ceramic, which differs from Example 1 in that the phosphate in the glaze is replaced with an equal amount of calcite.

[0120] Comparative Example 5, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the first fibrous body TiB fiber of the composite fiber in the blank is replaced with an equal amount of silicon carbide fiber.

[0121] Comparative Example 6, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the mass ratio of the first fiber body to the second fiber body of the composite fiber in the blank is 0.2:1.

[0122] Comparative Example 7, an antibacterial and easy-to-clean ceramic, differs from Example 1 in that the surfactant in the blank is replaced with an equal amount of kaolin.

[0123] Comparative Example 8 is an antibacterial and easy-to-clean ceramic, which differs from Example 1 in that sodium alginate in the blank is replaced with an equal amount of kaolin.

[0124] Comparative Example 9 is an antibacterial and easy-to-clean ceramic, which differs from Example 1 in that the composite fibers in the green body preparation process do not undergo a pretreatment process.

[0125] Comparative Example 10 is an antibacterial and easy-to-clean ceramic. The difference between it and Example 1 is that the green body is prepared by conventional pressing instead of isostatic pressing.

[0126] Performance testing

[0127] 1. Antibacterial properties

[0128] According to the "JC / T 897-2014 Antibacterial Ceramic Products Antibacterial Properties", the 50mm*50mm ceramic test pieces prepared in each example and comparative example were tested. Staphylococcus aureus AS1.89 and Escherichia coli AS1.90 were used to test whether the antibacterial rate of the ceramic test pieces prepared in this application met the national standard Class I judgment standard (99%). The test results are shown in Table 1.

[0129] 2. Durable antibacterial rate

[0130] After the 50mm*50mm ceramic test pieces prepared in each embodiment and each comparative example were washed 500 times, their durable antibacterial rate against Staphylococcus aureus AS1.89 and Escherichia coli AS1.90 was tested. The test results are shown in Table 1.

[0131] 3. Easy-to-clean performance

[0132] The easy-to-clean properties of 50mm*50mm ceramic test pieces prepared in each example and comparative example were tested according to GB / T 31859-2015 "Test Method for Easy-to-Cleanliness of Daily-Use Porcelain". The residual oil content per unit area was characterized by A: A≤0.50g / m². 2 This indicates "easy to clean"; 0.50g / m 2 <A≤1.00g / m 2 This indicates "relatively easy to clean"; 1.00g / m 2 <A≤1.50g / m 2 This indicates "cleanable"; A>1.50g / m 2 The value indicates "not cleanable". The test results are shown in Table 1.

[0133] Table 1

[0134]

[0135] Based on Examples 1-3, Comparative Example 1, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 are significantly better than those prepared in Comparative Example 1, while the ease of cleaning is similar between the two. The test results show that when the active ingredients, zirconium oxide powder and zinc oxide powder, are not made into nano-sized powders, it is difficult to fully utilize the high antibacterial activity of nanoparticles within the system. Furthermore, excessively large particles are difficult to load within the mesoporous structure of the carrier used in this application, thus affecting the escape of metal ions and hindering their deactivation by other components in the system. Therefore, Comparative Example 1 cannot achieve the expected antibacterial effect and long-lasting antibacterial performance.

[0136] Based on Examples 1-3, Comparative Example 2, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 were significantly better than those prepared in Comparative Example 2. The test results show that the content of zinc oxide nanoparticles in Comparative Example 2 was too low relative to the overall proportion of active ingredients, resulting in low zinc ion activity in the glaze and thus failing to achieve effective antibacterial and bacteriostatic effects.

[0137] Based on Examples 1-3, Comparative Example 3, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 were significantly better than those prepared in Comparative Example 3, but the effect on the easy-to-clean performance of the ceramic specimens in Comparative Example 3 was minimal. The test results show that the first antibacterial agent in the glaze of Comparative Example 3 lacks a mesoporous carrier to effectively support the nano-antibacterial particles, thus failing to achieve the expected antibacterial effect. Furthermore, it significantly impacts the long-term antibacterial stability of the ceramic specimens; the lack of a carrier leads to the leaching of antibacterial active substances during long-term use. However, the dense glass material on the surface actually improves the hydrophobic and oleophobic properties of the glaze to some extent.

[0138] Based on Examples 1-3, Comparative Example 4, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 were significantly better than those prepared in Comparative Example 4, while the easy-to-clean performance of Comparative Example 4 was significantly reduced. The test results show that phosphates within the glaze layer not only have a significant impact on the adhesion of antibacterial active ingredients but also on the formation of a uniform and stable glassy structure layer on the glaze surface, further affecting the easy-to-clean performance of the ceramic material.

[0139] Based on Examples 1-3, Comparative Examples 5-6, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 are significantly better than those prepared in Comparative Examples 5-6. The test results show that the TiB fibers, the first fibrous component in the composite fiber, play an indispensable role in the antibacterial performance and long-term antibacterial stability of the glaze layer. The fibrous structure of the TiB whiskers can efficiently support cuprous oxide, and the three-dimensional composite structure jointly constructed with the antibacterial particles effectively reduces the significant non-uniform strain distribution between the matrix and fiber regions, resulting in more uniform dispersion of the antibacterial particles and higher antibacterial activity.

[0140] Combining Examples 1-3, Comparative Examples 7-8, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 were significantly better than those prepared in Comparative Examples 7-8. The test results show that the functional components, surfactants and sodium alginate, play important roles in the green body system. Specifically, the surfactants prevent the aggregation or precipitation of cuprous oxide particles in the second antibacterial agent, maintaining their stable dispersion and ensuring a long-lasting antibacterial effect after the green body is formed. Sodium alginate, on the other hand, can initially chelate copper ions in the preceding processing steps, thereby regulating the reactivity of copper ions.

[0141] Based on Examples 1-3, Comparative Example 9, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 are significantly better than those prepared in Comparative Example 9, while the easy-to-clean performance of Comparative Example 9 is significantly reduced. The test results show that because the composite fibers were not pretreated during the green body preparation process, the length, aspect ratio, and other parameters of the fiber structure were all within unreasonable ranges. In particular, the excessively long and intricate filamentous fiber structure has a significant adverse effect on the green body forming and indirectly affects the glaze coating adhesion, thus failing to form ceramic products with both antibacterial and easy-to-clean properties.

[0142] Based on Examples 1-3, Comparative Example 10, and Table 1, the antibacterial rate and durable antibacterial rate of the ceramic specimens prepared in Examples 1-3 are significantly better than those prepared in Comparative Example 10, while the easy-to-clean performance of Comparative Example 10 is somewhat reduced. The test results show that isostatic pressing effectively eliminates the voids between the antibacterial particles and the fibrous structure, significantly improving the density and strength of the green body. This prevents the antibacterial agent in the glaze or green body from flowing out during long-term use and has a significant impact on the appearance and forming quality of ceramic products.

[0143] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for preparing an antibacterial and easy-to-clean ceramic, characterized in that, Includes the following steps: S1. Glaze preparation: Calcite, wollastonite, potassium feldspar and sodium feldspar are ball-milled and mixed evenly to obtain glaze powder. The active ingredients in the first antibacterial agent are loaded onto the carrier through vacuum permeation. The first antibacterial agent, phosphate and water are added to the glaze powder. The temperature is raised to 55-65℃ and stirred at high speed of 1000-1100r / min for 1-2h. The mixture is then allowed to stand to obtain glaze slurry. S2. Green body preparation: Kaolin, bentonite, dolomite, shell powder, potassium feldspar, sodium feldspar and quartz are mixed evenly and the green body powder is obtained by wet ball milling; the composite fiber is pretreated and surfactant, rutile titanium dioxide, sodium alginate and second antibacterial agent are added and dissolved and mixed, then the green body powder and water are added and stirred, heated to 90-100℃, and pressed into shape to obtain the green body; S3. Preliminary firing: Let the green body stand naturally for 20-24 hours, control the moisture content inside the green body to 1%-6%, then calcine the green body at 1200-1400℃ for 12-24 hours, and cool it naturally to obtain the raw green body. S4. Glazing: The glaze is sprayed onto the surface of the unglazed body to obtain a ceramic preliminary product; S5. Secondary firing: The initial ceramic product is calcined at 1150-1350℃ for 6-12 hours and then naturally cooled to obtain antibacterial and easy-to-clean ceramic. In step S2, the blank is pressed by isostatic pressing, and the isostatic pressing pressure is 180-260MPa. The antibacterial and easy-to-clean ceramic comprises a glaze and a body. By weight, the glaze comprises 50-90 parts calcite, 60-120 parts wollastonite, 30-60 parts potassium feldspar, 30-60 parts sodium feldspar, 44-60 parts phosphate, and 20-28 parts of a first antibacterial agent. The first antibacterial agent comprises an active ingredient and a carrier. The active ingredient comprises zirconium oxide nanopowder and zinc oxide nanopowder, and the mass ratio of the zirconium oxide nanopowder to the zinc oxide nanopowder is 1:(1.80-3.40). The raw material comprises 100-200 parts kaolin, 120-180 parts bentonite, 100-120 parts dolomite, 580-600 parts shell powder, 60-90 parts potassium feldspar, 50-70 parts sodium feldspar, 80-100 parts quartz, 45-75 parts rutile titanium dioxide, 50-60 parts sodium alginate, 50-70 parts composite fiber, 20-36 parts surfactant, and 40-50 parts second antibacterial agent; the second antibacterial agent includes cuprous oxide; the composite fiber comprises a first fiber body and a second fiber body, and the first fiber body includes TiB fiber. In step S2, the pretreatment of the composite fiber includes cutting the first fiber body and the second fiber body into short fibers, wherein the aspect ratio of the first fiber body is 20-40, and / or the length of the second fiber body is 0.1-0.5 mm; The carrier includes one or more of activated carbon, multi-walled carbon nanotubes, and silica. The zirconium oxide nanopowder has a particle size of 50-500 nm, and / or the zinc oxide has a particle size of 50-100 nm. The phosphate includes one or more of ammonium dihydrogen phosphate and diammonium hydrogen phosphate; The mass ratio of the first fiber to the second fiber is 1:(0.2-0.5). The surfactant includes one or more of polyvinylpyrrolidone (PVP) and hexadecyltrimethylammonium bromide (CTAB).

2. An antibacterial and easy-to-clean ceramic, prepared by the method described in claim 1, characterized in that, The second fiber body includes one or more of silicon carbide fibers and alumina fibers.

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