A method for preparing rare earth-silver composite antibacterial glaze

Abstract

The invention discloses a method for preparing a rare earth-silver composite antibacterial glaze, which uses a base glaze and a rare earth-silver composite antibacterial agent as a formula system, and combines neodymium, praseodymium, and silver ions in the rare earth-silver composite antibacterial agent with TiO in the base glaze. 2 , and ZnO play a multi-synergistic antibacterial role and synergistic sustained-release effect of Ag‑Zn‑Nd‑Pr‑Ti, thereby greatly improving the antibacterial rate of antibacterial ceramic products and solving the problem of insufficient long-term effectiveness of antibacterial ceramics in the existing technology. It has a positive effect on people's health and can be widely used in public places such as toilets, hospitals, kindergartens, swimming pools, and schools.

Description

Technical Field

[0001] The invention relates to the technical field of antibacterial glazes, and in particular to a method for preparing a rare earth-silver composite antibacterial glaze. Background Art

[0002] Ceramic products, whether they are building ceramics, sanitary ceramics or daily-use ceramics, are closely related to people's lives. People will come into contact with a large number of ceramic products during their home life or activities in public places. Most of these ceramic products are in a damp environment and are easily contaminated and breed pathogenic bacteria, causing disease transmission and other problems that endanger human health. With the improvement of living standards, people are increasingly in demand for high-quality antibacterial products for their own safety considerations and enhanced awareness of hygiene and health. Therefore, it is particularly important to use antibacterial ceramics in these scenarios to reduce the pollution of ceramic products and cross-infection in public places. This provides a broad market prospect for the development of antibacterial ceramics. However, the existing antibacterial ceramics still generally have the problems of low antibacterial rate and insufficient antibacterial long-term effect. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for preparing a rare earth-silver composite antibacterial glaze. The method uses a basic glaze and a rare earth-silver composite antibacterial agent as a formula system, and the neodymium element, praseodymium element, silver ions in the rare earth-silver composite antibacterial agent and TiO2 and ZnO in the basic glaze play a multi-component synergistic antibacterial effect and a synergistic sustained-release effect of Ag-Zn-Nd-Pr-Ti, thereby greatly improving the antibacterial rate of the antibacterial ceramic product and solving the problem of insufficient long-term effectiveness of the antibacterial ceramics in the prior art.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] The invention provides a method for preparing a rare earth-silver composite antibacterial glaze. The rare earth-silver composite antibacterial glaze is composed of a base glaze and a rare earth-silver composite antibacterial agent. The raw materials of the base glaze are 18-21wt% of potassium feldspar, 12-16wt% of sodium feldspar, 14-17wt% of quartz, 8-13wt% of limestone, 5-8wt% of zirconium silicate, 4-6wt% of zinc oxide, 4-7wt% of titanium dioxide, 6-9wt% of aluminum oxide, 6-9wt% of ball clay, and 7-10wt% of talc. The raw materials of the rare earth-silver composite antibacterial agent are 0.5-0.8wt% of neodymium oxide, 0.5-0.8wt% of praseodymium oxide, and 0.5-1wt% of silver nitrate, respectively, in an amount of the base glaze. The preparation method comprises the following steps:

[0006] (1) The raw materials of the base glaze and the rare earth-silver composite antibacterial agent are weighed and mixed according to the ratio, and then ball milled and sieved to obtain the rare earth-silver composite antibacterial glaze slurry.

[0007] (2) applying the rare earth-silver composite antibacterial glaze slurry to the surface of the ceramic body by dipping, and sintering the obtained glaze body at a temperature of 1200-1240° C. after drying, keeping the temperature for 1-2 hours, and obtaining the rare earth-silver composite antibacterial glaze layer after natural cooling.

[0008] Furthermore, in step (1) of the present invention, ball milling is performed according to the ratio of material: ball: water = 1: 2-3: 0.6-0.8, and the ball milling time is 40-50 minutes; the specific gravity of the glaze slurry is 1.65-1.70 kg / L. The glazing thickness in step (2) is 0.6-0.8 mm. In the above scheme, the antibacterial rate of the rare earth-silver composite antibacterial glaze layer of the present invention against Escherichia coli and Staphylococcus aureus exceeds 98%, and the antibacterial rate against the two bacteria is still above 95% after one year.

[0009] The present invention has the following beneficial effects:

[0010] (1) The present invention utilizes that the outermost layer of the neodymium oxide and praseodymium oxide ions in the composite antibacterial agent has more unpaired electrons, which are easy to react with Ag. + The interaction occurs to synthesize a coordination compound with antibacterial effect, enhancing its function of disinfection and sterilization and inhibiting bacterial growth and reproduction; at the same time, the zinc oxide and silver nitrate in the base glaze can compound with each other to produce Ag + and active oxygen, while the addition of rare earth elements neodymium and praseodymium can catalyze the composite zinc oxide to produce more O2- and OH with oxidizing ability. - Free radicals such as chlorinated parasites can destroy the bacterial cell membrane and the DNA, protein and other substances in the membrane, hindering their life activities and eventually leading to death, thereby playing a chemical antibacterial role.

[0011] (2) The TiO2 contained in the base glaze of the present invention can capture photocatalytic electrons through the valence electron bands of the neodymium and praseodymium elements to form electron-hole pairs, which greatly improves the absorption rate of ultraviolet rays by the antibacterial ceramic products, thereby playing a physical antibacterial role. Under the formula system of the present invention, the neodymium, praseodymium, and silver ions in the rare earth-silver composite antibacterial agent can play a multi-component synergistic antibacterial role and synergistic sustained-release effect of Ag-Zn-Nd-Pr-Ti with the TiO2 and ZnO in the base glaze, which not only greatly improves the antibacterial rate of the antibacterial ceramic products, but also solves the problem of insufficient long-term effectiveness of the antibacterial ceramics.

[0012] (3) The invention adds rare earth-silver composite antibacterial agent to the base glaze, which not only makes ceramic products occupy a place in the field of high-end decoration, but also has the function of sterilization and disinfection, so that it can be widely used in public places such as toilets, hospitals, kindergartens, swimming pools, schools, etc. The popularization and application of antibacterial ceramics can effectively avoid cross-infection of bacteria during social activities, and fully kill Escherichia coli and Staphylococcus aureus existing in the daily life environment, and can also prevent the growth of some similar harmful bacteria and microorganisms, which has a positive effect on people's life and health.

[0013] The present invention will be described in further detail below with reference to the embodiments. DETAILED DESCRIPTION

[0014] Embodiment 1:

[0015] The present embodiment provides a method for preparing a rare earth-silver composite antibacterial glaze, wherein the rare earth-silver composite antibacterial glaze is composed of a base glaze and a rare earth-silver composite antibacterial agent; wherein the raw material composition of the base glaze is 21wt% of potassium feldspar, 16wt% of sodium feldspar, 17wt% of quartz, 8wt% of limestone, 5wt% of zirconium silicate, 4wt% of zinc oxide, 4wt% of titanium dioxide, 7wt% of aluminum oxide, 8wt% of ball clay, and 10wt% of talc; the raw material composition of the rare earth-silver composite antibacterial agent is 0.5wt% of neodymium oxide, 0.5wt% of praseodymium oxide, and 0.5wt% of silver nitrate in an amount of the base glaze, respectively; the preparation method has the following steps:

[0016] (1) After weighing and mixing the raw materials of the base glaze and the rare earth-silver composite antibacterial agent, ball milling was performed at a ratio of material: ball: water = 1:2:0.7 for 40 min. After passing through a 250-mesh standard sieve, a rare earth-silver composite antibacterial glaze slurry with a specific gravity of 1.67 kg / L was obtained.

[0017] (2) The rare earth-silver composite antibacterial glaze slurry is applied to the surface of the ceramic body by dipping, and the glazing thickness is 0.6 mm. The obtained glaze body is placed in a drying oven at 100°C for 2 hours, and then sintered in a kiln at 1200°C for 1 hour. After natural cooling, a rare earth-silver composite antibacterial glaze layer is obtained.

[0018] Embodiment 2:

[0019] The present embodiment provides a method for preparing a rare earth-silver composite antibacterial glaze, wherein the rare earth-silver composite antibacterial glaze is composed of a base glaze and a rare earth-silver composite antibacterial agent; wherein the raw material composition of the base glaze is 18wt% of potassium feldspar, 15wt% of sodium feldspar, 16wt% of quartz, 10wt% of limestone, 6wt% of zirconium silicate, 6wt% of zinc oxide, 5wt% of titanium dioxide, 6wt% of aluminum oxide, 9wt% of ball clay, and 9wt% of talc; the raw material composition of the rare earth-silver composite antibacterial agent is 0.6wt% of neodymium oxide, 0.6wt% of praseodymium oxide, and 0.7wt% of silver nitrate in an amount of the base glaze, respectively; the preparation method has the following steps:

[0020] (1) After weighing and mixing the raw materials of the above-mentioned base glaze and the rare earth-silver composite antibacterial agent, ball milling was performed at a ratio of material: ball: water = 1:2:0.8, and the ball milling time was 50 min. After passing through a 250-mesh standard sieve, a rare earth-silver composite antibacterial glaze slurry with a specific gravity of 1.65 kg / L was obtained.

[0021] (2) The rare earth-silver composite antibacterial glaze slurry is applied to the surface of the ceramic body by dipping, and the glazing thickness is 0.7 mm. The obtained glaze body is placed in a drying oven at 100°C for 2 hours, and then placed in a kiln for sintering at 1220°C and kept warm for 1.5 hours. After natural cooling, a rare earth-silver composite antibacterial glaze layer is obtained.

[0022] Embodiment three:

[0023] The present embodiment provides a method for preparing a rare earth-silver composite antibacterial glaze, wherein the rare earth-silver composite antibacterial glaze is composed of a base glaze and a rare earth-silver composite antibacterial agent; wherein the raw material composition of the base glaze is 20wt% of potassium feldspar, 13wt% of sodium feldspar, 14wt% of quartz, 11wt% of limestone, 7wt% of zirconium silicate, 5wt% of zinc oxide, 6wt% of titanium dioxide, 9wt% of aluminum oxide, 7wt% of ball clay, and 8wt% of talc; the raw material composition of the rare earth-silver composite antibacterial agent is 0.7wt% of neodymium oxide, 0.7wt% of praseodymium oxide, and 0.9wt% of silver nitrate in an amount of the base glaze, respectively; the preparation method has the following steps:

[0024] (1) After weighing and mixing the raw materials of the above-mentioned base glaze and the rare earth-silver composite antibacterial agent, ball milling was performed according to the ratio of material: ball: water = 1: 3: 0.6, and the ball milling time was 40 min. After passing through a 250-mesh standard sieve, a rare earth-silver composite antibacterial glaze slurry with a specific gravity of 1.69 kg / L was obtained.

[0025] (2) The rare earth-silver composite antibacterial glaze slurry is applied to the surface of the ceramic body by dipping, and the glazing thickness is 0.8 mm. The obtained glaze body is placed in a drying oven at 100°C for 2 hours, and then placed in a kiln for sintering at 1230°C and kept warm for 1.5 hours. After natural cooling, a rare earth-silver composite antibacterial glaze layer is obtained.

[0026] Embodiment 4:

[0027] The present embodiment provides a method for preparing a rare earth-silver composite antibacterial glaze, wherein the rare earth-silver composite antibacterial glaze is composed of a base glaze and a rare earth-silver composite antibacterial agent; wherein the raw material composition of the base glaze is 18wt% of potassium feldspar, 12wt% of sodium feldspar, 15wt% of quartz, 13wt% of limestone, 8wt% of zirconium silicate, 6wt% of zinc oxide, 7wt% of titanium dioxide, 8wt% of aluminum oxide, 6wt% of ball clay, and 7wt% of talc; the raw material composition of the rare earth-silver composite antibacterial agent is 0.8wt% of neodymium oxide, 0.8wt% of praseodymium oxide, and 1wt% of silver nitrate in an amount of the base glaze, respectively; the preparation method has the following steps:

[0028] (1) After weighing and mixing the raw materials of the above-mentioned base glaze and the rare earth-silver composite antibacterial agent, ball milling was performed according to the ratio of material: ball: water = 1: 3: 0.7, and the ball milling time was 50 min. After passing through a 250-mesh standard sieve, a rare earth-silver composite antibacterial glaze slurry with a specific gravity of 1.70 kg / L was obtained.

[0029] (2) The rare earth-silver composite antibacterial glaze slurry is applied to the surface of the ceramic body by dipping, and the glazing thickness is 0.8 mm. The obtained glaze body is placed in a drying oven at 100°C for 2 hours, and then sintered in a kiln at 1240°C for 2 hours. After natural cooling, a rare earth-silver composite antibacterial glaze layer is obtained.

[0030] The raw materials used in the embodiments of the present invention, the zinc oxide, titanium dioxide, aluminum oxide in the base glaze, and the neodymium oxide, praseodymium oxide, and silver nitrate in the rare earth-silver composite antibacterial agent are all chemically pure raw materials (ZnO, TiO2, Al2O3, Nd2O3, Pr6O 11 , AgNO3≥99.5%). The chemical compositions of the remaining raw materials are shown in Table 1.

[0031] Table 1 Chemical composition of the basic glaze raw materials of the present invention (wt%)

[0032]

[0033] Antibacterial performance test:

[0034] The test was conducted according to the detection method of JC / T897-2014 "Antibacterial Performance of Antibacterial Ceramic Products". Taking ordinary antibacterial ceramics as comparative examples, the antibacterial performance test results of the rare earth-silver composite antibacterial glaze layer prepared in each embodiment of the present invention and the ordinary antibacterial ceramic glaze layer of the comparative example are shown in Table 2.

[0035] Table 2 Antibacterial performance test results of the embodiments of the present invention and the comparative examples

[0036]

[0037] It can be seen from the test results in Table 2 that the rare earth-silver composite antibacterial glaze layer prepared by the embodiment of the present invention has a good antibacterial effect, and the antibacterial rate of Escherichia coli and Staphylococcus aureus is more than 98%, far exceeding the national standard of 90%. Compared with the comparative example, the antibacterial rate of the present invention against the two bacteria is about 99% when it is just prepared, far ahead of the antibacterial rate of the comparative example; after one year, the antibacterial rate of the comparative example against the two bacteria has weakened to less than 85%, which has not reached the national standard of 90%, while the antibacterial rate of the present invention against Escherichia coli and Staphylococcus aureus is still as high as 95% after one year, far exceeding the national standard; in the comparison of the antibacterial rate after two years, the comparative example has less than 25% antibacterial rate, while the embodiment of the present invention still has more than 45% antibacterial rate, with a long-lasting antibacterial effect.

Claims

1. A method for preparing a rare earth-silver composite antibacterial glaze, characterized in that: The rare earth-silver composite antibacterial glaze is composed of a base glaze and a rare earth-silver composite antibacterial agent; the raw materials of the base glaze are 18-21wt% of potassium feldspar, 12-16wt% of sodium feldspar, 14-17wt% of quartz, 8-13wt% of limestone, 5-8wt% of zirconium silicate, 4-6wt% of zinc oxide, 4-7wt% of titanium dioxide, 6-9wt% of aluminum oxide, 6-9wt% of ball clay, and 7-10wt% of calcined talc; the raw materials of the rare earth-silver composite antibacterial agent are 0.5-0.8wt% of neodymium oxide, 0.5-0.8wt% of praseodymium oxide, and 0.5-1wt% of silver nitrate in an amount of 0.5-0.8wt% of the base glaze, respectively; the preparation method comprises the following steps: (1) weighing and mixing the raw materials of the base glaze and the rare earth-silver composite antibacterial agent, mixing by ball milling, and sieving to obtain a rare earth-silver composite antibacterial glaze slurry; (2) The rare earth-silver composite antibacterial glaze slurry is applied to the surface of the ceramic body by dipping, and the obtained glaze body is dried and sintered at a temperature of 1200-1240° C., kept warm for 1-2 hours, and naturally cooled to obtain a rare earth-silver composite antibacterial glaze layer; the antibacterial rate of the rare earth-silver composite antibacterial glaze layer against Escherichia coli and Staphylococcus aureus is more than 98%, and the antibacterial rate against the two bacteria is still above 95% after one year.

2. The method for preparing the rare earth-silver composite antibacterial glaze according to claim 1, characterized in that: In the step (1), ball milling is performed according to the ratio of material: ball: water = 1: 2-3: 0.6-0.8, and the ball milling time is 40-50 min; the specific gravity of the glaze slurry is 1.65-1.70 kg / L.

3. The method for preparing the rare earth-silver composite antibacterial glaze according to claim 1, characterized in that: The glazing thickness in step (2) is 0.6 to 0.8 mm.

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