A skin glaze ceramic tile and its preparation process

Abstract

The present invention provides a skin glaze ceramic tile and its preparation process, relating to the field of ceramic technology. The skin glaze ceramic tile provided by the present invention includes a ceramic tile body and a skin glaze layer sintered and formed on the surface of the ceramic tile body. The skin glaze layer includes a bottom glaze layer, a surface glaze layer, and a protective glaze layer formed in sequence along the ceramic tile body. The protective glaze layer is sintered and formed on the surface glaze layer by a protective glaze material. The protective glaze material, by mass fraction, includes: 50 - 60 parts of silicon dioxide, 7 - 10 parts of aluminum oxide, 1 - 2 parts of boron oxide, 2 - 3 parts of sodium oxide, 1 - 2 parts of potassium oxide, 15 - 20 parts of calcium oxide, 1 - 2 parts of magnesium oxide, 1 - 2 parts of lithium oxide, 0.1 - 0.5 parts of cesium oxide, 0.1 - 0.5 parts of barium oxide, 1 - 2 parts of zinc oxide, 1 - 2 parts of modified silicon oxynitride powder, 1 - 2 parts of binder, and 1 - 2 parts of dispersant. The skin glaze ceramic tile provided by the present invention has good abrasion resistance and can maintain the glossiness of the glaze surface during long-term use.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramics, and particularly to a skin glaze ceramic tile and a preparation process thereof. Background Art

[0002] Among current building floor materials, floor tiles with a glossiness of not less than 55 degrees are called bright tiles. Their surfaces are smooth and colorful, and are commonly used for indoor building floor paving, which can bring people a good visual experience. However, due to their too high glossiness, they are prone to reflection, and strong visual stimulation is likely to occur under high ambient light, causing discomfort to people's physical sensations. Therefore, ceramic tiles with a glossiness between 25 - 35 degrees and a delicate and smooth glaze surface - skin glaze ceramic tiles - have been widely used. Their surfaces present silk light or flash point gloss, and the tile surfaces are delicate and moist. Moreover, there is no strong reflection under strong ambient light, which can bring people a quiet and gentle visual experience.

[0003] For example, Chinese Patent with the publication number CN115557701A provides a glaze composition and a skin glaze ceramic tile. By using a combination of multiple glazes with different compositions and ratios, different melting changes can occur in the firing process, thereby causing changes in the glossiness of different glaze layers. As a result, the skin glaze ceramic tile can maintain the glaze surface glossiness between 25 - 35 degrees without additional polishing, and it is not overly reflective and will not cause the indoor space to be dim. However, after the ceramic tile is paved on the building floor, it needs to be used for a long time, and its service life often reaches 10 - 20 years. When dust adheres to the surface of the skin glaze ceramic tile and penetrates into it during long-term use, it will greatly affect the glossiness of the skin glaze surface, resulting in a dull surface and a decline in the appearance of the skin glaze ceramic tile. Therefore, there is an urgent need to provide a solution to improve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a skin glaze ceramic tile and a preparation process thereof. The skin glaze ceramic tile provided by the present invention has good wear resistance and can maintain the glaze surface glossiness during long-term use.

[0005] A skin glaze ceramic tile provided by the present invention includes a tile body and a skin glaze layer sintered and formed on at least one surface of the tile body. The skin glaze layer includes a bottom glaze layer, a surface glaze layer, and a protective glaze layer formed in sequence along the tile body. The protective glaze layer is sintered and formed on the surface glaze layer by a protective glaze. Calculated by mass parts, the protective glaze includes: 50 - 60 parts of silicon dioxide, 7 - 10 parts of aluminum oxide, 1 - 2 parts of boron oxide, 2 - 3 parts of sodium oxide, 1 - 2 parts of potassium oxide, 15 - 20 parts of calcium oxide, 1 - 2 parts of magnesium oxide, 1 - 2 parts of lithium oxide, 0.1 - 0.5 parts of cesium oxide, 0.1 - 0.5 parts of barium oxide, 1 - 2 parts of zinc oxide, 1 - 2 parts of modified silicon oxynitride powder, 1 - 2 parts of binder, and 1 - 2 parts of dispersant.

[0006] The skin glaze ceramic tile provided by the present invention has a skin glaze layer formed on the surface of the tile body, which can endow the tile surface with a skin-like feel, and at the same time can reduce the surface reflection of the ceramic tile, that is, inhibit the high-gloss reflection. In addition, the skin glaze layer can also play a protective role for the tile body, avoiding cracking of the tile body and internal cracks when under impact and temperature changes. In addition, the modified silicon oxynitride powder is dispersed in the protective glaze layer, which can significantly improve the surface hardness and wear resistance of the protective glaze layer, effectively resist external friction and scratching, maintain long-term beauty, improve the stability of the surface gloss of the protective glaze layer, and avoid dullness and matte appearance on the surface during long-term use.

[0007] Optionally, the binder includes at least one of sodium carboxymethyl cellulose, polyvinyl alcohol, sodium silicate, methyl cellulose, and sodium alginate.

[0008] Optionally, the dispersant includes at least one of sodium polyacrylate, sodium hexametaphosphate, and ethylenediamine di(o-hydroxyphenyl) acetic acid.

[0009] Optionally, the average particle size of the modified silicon oxynitride powder is 1-20 μm.

[0010] Optionally, the preparation method of the modified silicon oxynitride powder includes: after surface activation of the silicon oxynitride powder, stirring and dispersing it in tetraethyl orthosilicate and then separating to obtain a pre-modified body; after surface hydroxyl modification of molybdenum disulfide nanosheets, ultrasonically mixing and dispersing them with the pre-modified body and then separating and drying to obtain a modified intermediate; subjecting the modified intermediate to re-nitriding to obtain the modified silicon oxynitride powder. By surface activation of the silicon oxynitride powder, the number of surface active sites of the silicon oxynitride powder can be effectively increased, thereby improving the surface activity and surface reactivity of the silicon oxynitride, which is beneficial to surface modification treatment in tetraethyl orthosilicate, and a silica layer can be formed on the surface of the silicon oxynitride powder, thereby improving the compatibility of the silicon oxynitride powder in the protective glaze. At the same time, the silica on the surface of the silicon oxynitride can combine with the silica in the protective glaze during the sintering process, thereby effectively improving the position stability of the silicon oxynitride in the protective glaze layer.

[0011] Optionally, the preparation method of the silicon oxynitride powder includes the following steps: preheating silicon oxide in an oxygen atmosphere at 300-400 °C for 2-3 h, then heating the preheated silicon oxide in a nitrogen-containing atmosphere at a rate of 5-10 °C / min to 1400-1500 °C and holding for 20-30 h, and then performing vacuum degassing at 200-300 °C for 1-2 h and grinding and pulverizing to obtain the silicon oxynitride powder. Through the solid-gas nitridation reaction, the silanol groups in the silicon oxide powder can be nitrided into silamine groups, and after vacuum degassing, the pores and defects in the silicon oxynitride powder can be reduced, and the structural stability of the silicon oxynitride crystal can be promoted.

[0012] Optionally, the particle size of the silicon oxide is 1 - 10 μm.

[0013] Optionally, the nitrogen-containing atmosphere includes one of nitrogen and ammonia.

[0014] Optionally, the silicon oxide is ball-milled in an oxygen atmosphere at 100 - 200 °C for 30 - 40 min, and then preheated in an oxygen atmosphere at 300 - 400 °C for 2 - 3 h.

[0015] Optionally, the mass content of nitrogen in the silicon oxynitride powder is 20 - 40%.

[0016] Optionally, the silicon oxynitride powder is surface-activated in an active agent, and the active agent includes at least one of cetyltrimethylammonium chloride, lauryldimethylamine oxide, and octadecyldimethylbenzylammonium chloride.

[0017] Optionally, after the silicon oxynitride powder is surface-activated, it is stirred and dispersed in tetraethyl orthosilicate at a solid-liquid ratio of 0.1 - 0.3 g / mL.

[0018] Optionally, after being stirred and dispersed in tetraethyl orthosilicate, it is separated, washed, and dried at 80 - 100 °C to obtain a pre-modified precursor.

[0019] Optionally, the average particle size of the nano-molybdenum disulfide is 1 - 100 nm.

[0020] Optionally, the nano-silicon sulfide is surface-hydroxyl modified in an alkaline solution, and the solute in the alkaline solution includes one of sodium hydroxide and potassium hydroxide.

[0021] Optionally, when the nano-molybdenum disulfide is surface-modified and ultrasonically mixed with the pre-modified precursor, the surface-modified nano-molybdenum disulfide and the pre-modified precursor are ultrasonically mixed in absolute ethanol.

[0022] Optionally, the mass ratio of nano-molybdenum disulfide to the pre-modified precursor is 1:(20 - 25).

[0023] Optionally, when the modified intermediate is re-nitrided to obtain the modified silicon oxynitride powder, it includes: keeping the modified intermediate in a nitrogen atmosphere or ammonia atmosphere at 1400 - 1500 °C for 5 - 10 h, then performing vacuum degassing and cooling and grinding to obtain the modified silicon oxynitride powder.

[0024] Optionally, the bottom glaze layer is sintered and formed on the tile body from the bottom glaze material. Calculated by mass parts, the bottom glaze material includes: 20 - 30 parts of alumina, 50 - 55 parts of silicon dioxide, 2 - 3 parts of potassium oxide, 10 - 15 parts of alumina, 10 - 15 parts of calcium oxide, 1 - 2 parts of magnesium oxide, 1 - 2 parts of sodium oxide, 1 - 2 parts of zinc oxide, 1 - 2 parts of sodium carboxymethyl cellulose, and 1 - 2 parts of sodium hexametaphosphate.

[0025] Optionally, the surface glaze layer is sintered and formed on the bottom glaze layer by surface glaze material. Calculated by mass parts, the surface glaze material includes: 15-20 parts of alumina, 55-60 parts of silica, 2-3 parts of potassium oxide, 10-15 parts of alumina, 10-15 parts of calcium oxide, 1-2 parts of magnesium oxide, 1-2 parts of sodium oxide, 1-2 parts of zinc oxide, 1-2 parts of cesium oxide, 1-2 parts of sodium carboxymethyl cellulose, and 1-2 parts of sodium hexametaphosphate.

[0026] In a second aspect, the present invention also provides a preparation process for skin glaze ceramic tiles, comprising the following steps: spraying the protective glaze material on the surface of the surface glaze layer, and performing high-temperature sintering at 1200-1300 °C and then polishing and forming to obtain the skin glaze ceramic tiles; the spraying amount of the protective glaze material on the surface of the surface glaze layer is 300-400 g / m 2 .

[0027] In summary, a skin glaze ceramic tile provided by the present invention has the following beneficial effects:

[0028] 1. The surface of the ceramic tile has a skin-like feel, and at the same time, it can reduce the surface reflection of the ceramic tile, that is, inhibit high-gloss reflection, and has good mechanical properties and adhesion strength.

[0029] 2. The modified silicon oxynitride powder is dispersed in the protective glaze layer, which can significantly improve the surface hardness and wear resistance of the protective glaze layer, effectively resist external friction and scratching, maintain long-term beauty, improve the stability of the surface gloss of the protective glaze layer, and avoid dullness and matte appearance on the surface during long-term use. Specific Embodiments

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which the present invention belongs.

[0031] The present invention provides a skin glaze ceramic tile, comprising a tile body and a skin glaze layer sintered and formed on at least one surface of the tile body. Specifically, the skin glaze layer formed on the surface of the tile body can endow the tile surface with a skin-like feel, and at the same time, it can reduce the surface reflection of the ceramic tile, that is, inhibit high-gloss reflection. In addition, the skin glaze layer can also play a protective role for the tile body, avoiding cracking of the tile body and internal cracks when subjected to impact and temperature changes.

[0032] The skin glaze layer includes a base glaze layer, a surface glaze layer, and a protective glaze layer formed successively along the ceramic tile body. By setting the skin glaze layer as a three-layer structure, different glaze layers can endow the ceramic tile with different properties. For example, the base glaze layer can improve the bonding strength between the skin glaze layer and the ceramic tile, preventing the skin glaze layer and the ceramic tile body from peeling during the sintering process. The surface glaze layer can play a decorative role. For example, various colors and patterns can be set in the surface glaze layer to meet the aesthetic settings of different consumers and different product models.

[0033] Specifically, the ceramic tile body in the skin glaze ceramic tile is sintered and formed using a ceramic tile green body, and it can adopt the blank combinations commonly used in the field for ceramic tile forming, with the necessity of maintaining a stable form after sintering.

[0034] The base glaze layer, surface glaze layer, and protective glaze layer in the skin glaze layer have different chemical compositions. The protective glaze layer is sintered and formed on the surface glaze layer using a protective glaze material. Calculated by mass parts, the protective glaze material includes: 50 - 60 parts of silicon dioxide, 7 - 10 parts of aluminum oxide, 1 - 2 parts of boron oxide, 2 - 3 parts of sodium oxide, 1 - 2 parts of potassium oxide, 15 - 20 parts of calcium oxide, 1 - 2 parts of magnesium oxide, 1 - 2 parts of lithium oxide, 0.1 - 0.5 parts of cesium oxide, 0.1 - 0.5 parts of barium oxide, 1 - 2 parts of zinc oxide, 1 - 2 parts of modified silicon oxynitride powder, 1 - 2 parts of adhesive, and 1 - 2 parts of dispersant.

[0035] Specifically, during the sintering process of the protective glaze material, silicon dioxide softens and flows at high temperature and then begins to form a glass network, providing a basic skeleton structure for the protective glaze layer, endowing the protective glaze layer with basic strength and structural stability. At the same time, it can penetrate into the surface glaze layer to improve the bonding strength between the protective glaze layer and the surface glaze layer. In addition, the stable chemical properties of silicon dioxide itself can improve the resistance of the protective glaze layer to the erosion of chemical substances such as acids and alkalis.

[0036] Specifically, during the sintering process of the protective glaze material, aluminum oxide can interact with silicon dioxide. First, part of the aluminum oxide will dissolve and combine in the glass network formed by silicon dioxide to form a composite network structure, improving the adhesiveness and overall mechanical properties of the protective glaze layer. At the same time, aluminum oxide and silicon dioxide can generate mullite crystals, which can not only greatly improve the hardness and thermal shock resistance of the glaze surface but also adjust the refractive properties and gloss of the protective glaze layer.

[0037] Specifically, during the sintering process of the protective glaze, boron oxide softens in advance and interferes when silica forms a glassy framework, while improving the fluidity of silica, which is beneficial to improving the surface flatness and mechanical strength of the protective glaze layer. In addition, boron oxide can also reduce the overall melting temperature of the protective glaze, enabling the glaze to form a uniform protective glaze layer at a relatively low temperature. Moreover, boron oxide can fill within the silica glass framework to fill the pores and defects inside the protective glaze layer, improving the surface sealing degree of the protective glaze layer to enhance the resistance to dust and pollution, and being beneficial to improving the retention performance of the surface gloss of the protective glaze.

[0038] Specifically, during the sintering process of the protective glaze, sodium oxide and potassium oxide can play a synergistic role with boron oxide. The combined action of the two can effectively reduce the sintering temperature of the protective glaze, thereby protecting the tile body and the primer layer and topcoat layer on the surface of the tile body. In addition, sodium oxide can also adjust the gloss and transparency of the surface of the protective glaze, so that the gloss of the surface of the protective glaze layer meets the light perception requirements between 25 - 35 degrees.

[0039] Specifically, during the sintering process of the protective glaze, calcium oxide can fill the cracks and defects inside the protective glaze layer, thereby jointly improving the surface sealing degree of the protective glaze layer with boron oxide, reducing the surface porosity and internal defect rate of the protective glaze layer. At the same time, calcium oxide can form calcium silicate crystals with silica during the sintering process. Through the setting of calcium silicate crystals and mullite crystals, the gloss and light refraction performance of the surface of the protective glaze layer can be comprehensively adjusted.

[0040] Specifically, during the sintering process of the protective glaze, magnesium oxide can form a silicon-magnesium compound with silica, which can improve the chemical stability of the protective glaze layer. At the same time, magnesium oxide can also improve the corrosion resistance and anti-pollution performance of the surface of the protective glaze layer. In addition, magnesium oxide can also adjust the thermal expansion performance of the protective glaze layer to avoid a too large difference in the thermal expansion coefficient between the protective glaze layer and the topcoat layer during the sintering process, resulting in the detachment of the glaze surface.

[0041] Specifically, during the sintering process of the protective glaze, lithium oxide can react with silica at a relatively low temperature, thereby destroying the glass phase structure, effectively reducing the melting temperature of the protective glaze, and significantly improving the fluidity of the protective glaze, enabling the protective glaze to adhere well to the topcoat layer during the melting and sintering process, avoiding problems such as sagging and uneven thickness. Moreover, lithium oxide can also improve the gloss and transparency of the protective glaze layer, so that the surface gloss of the protective glaze layer is stably maintained between 25 - 35 degrees in synergistic action with other components.

[0042] Specifically, during the sintering process of the protective glaze, cesium oxide can change the surface tension of the molten protective glaze, making it easier for the protective glaze to spread evenly, thereby improving the surface flatness of the protective glaze layer. In addition, cesium oxide can also affect the crystallization formation process of crystals such as calcium silicate and mullite, so as to adjust the optical and mechanical properties of the surface of the protective glaze layer.

[0043] In the protective glaze, the binder can improve the bonding strength of each component in the glaze to form a uniform mixture. At the same time, during the glazing process, it can make the glaze better adhere to the surface of the glaze layer, preventing the protective glaze from falling off during the drying and sintering processes. In addition, during the sintering process, the binder gradually pyrolyzes, and some elements enter the protective glaze layer, while some elements are burned off by gas to avoid affecting the performance of the protective glaze layer. The dispersant can be compounded with the binder in the protective glaze to prevent agglomeration of each component in the glaze, and at the same time can reduce the surface energy of each component in the protective glaze, enabling each component in the glaze to be uniformly mixed during the sintering process, thereby adjusting the sintering thickness of the protective glaze layer.

[0044] Specifically, the binder in the protective glaze includes at least one of sodium carboxymethyl cellulose, polyvinyl alcohol, sodium silicate, methyl cellulose, and sodium alginate, and the dispersant includes at least one of sodium polyacrylate, sodium hexametaphosphate, and ethylenediamine di-o-hydroxyphenyl acetic acid.

[0045] In fact, the modified silicon oxynitride powder is evenly distributed in the protective glaze. During the sintering process of the protective glaze, the modified silicon oxynitride powder can significantly improve the surface hardness and wear resistance of the protective glaze layer, effectively resist external friction and scratching, maintain long-term beauty, improve the stability of the surface gloss of the protective glaze layer, and avoid dullness and matte appearance on the surface during long-term use. Specifically, after the modification treatment of the silicon oxynitride powder, the compatibility of the silicon oxynitride powder in the protective glaze can be effectively improved, thus forming a stable glaze layer structure. In fact, the average particle size of the modified silicon oxynitride powder is 1-20 μm.

[0046] Specifically, the preparation method of the modified silicon oxynitride powder includes: after surface activation of the silicon oxynitride powder, stirring and dispersing it in tetraethyl orthosilicate and then separating to obtain a pre-modified body; after surface hydroxyl modification of nano-molybdenum disulfide, ultrasonic mixing and dispersing it with the pre-modified body and then separating and drying to obtain a modified intermediate; and performing re-nitriding on the modified intermediate to obtain the modified silicon oxynitride powder.

[0047] By surface-activating the silicon oxynitride powder, the number of surface active sites of the silicon oxynitride powder can be effectively increased, thereby improving the surface activity and surface reactivity of the silicon oxynitride, which is beneficial to the surface modification treatment in tetraethyl orthosilicate. In fact, by immersing the silicon oxynitride powder in tetraethyl orthosilicate, tetraethyl orthosilicate can form a silica layer on the surface of the silicon oxynitride powder through hydrolysis, thereby improving the compatibility of the silicon oxynitride powder in the protective glaze. At the same time, the silica on the surface of the silicon oxynitride can combine with the silica in the protective glaze during the sintering process, thereby effectively improving the position stability of the silicon oxynitride in the protective glaze layer.

[0048] In some embodiments, a method for preparing silicon oxynitride powder includes the following steps: preheating silicon oxide in an oxygen atmosphere at 300 - 400 °C for 2 - 3 h, then heating the preheated silicon oxide in a nitrogen-containing atmosphere at a rate of 5 - 10 °C / min to 1400 - 1500 °C and holding for 20 - 30 h, and then performing vacuum degassing at 200 - 300 °C for 1 - 2 h and grinding to obtain silicon oxynitride powder.

[0049] By preheating silicon oxide in an oxygen atmosphere at 300 - 400 °C, the impurities therein can be burned off, and the purity and oxygen content of the silicon oxide can be increased. In addition, by subjecting the preheated silicon oxide to high-temperature nitridation in a nitrogen-containing atmosphere, the silanol groups in the silicon oxide powder can be nitrided into silazane groups through a solid-gas nitridation reaction. After vacuum degassing, the pores and defects in the silicon oxynitride powder can be reduced, and the structural stability of the silicon oxynitride crystal can be promoted.

[0050] In some embodiments, when preheating silicon oxide in an oxygen atmosphere at 300 - 400 °C, the average particle size of the silicon oxide used is 1 - 10 μm. By selecting silicon oxide with a small particle size, the contact area between the silicon oxide powder and the oxygen atmosphere can be increased, thereby forming a more reactive silicon oxide powder, which is beneficial to nitridation in a nitrogen-containing atmosphere. At the same time, silicon oxide with a relatively uniform particle size is beneficial to controlling the degree of nitridation.

[0051] In some embodiments, the nitrogen-containing atmosphere used includes one of nitrogen and ammonia. By adjusting the nitrogen element content and type of the nitrogen-containing atmosphere, as well as the nitridation temperature and time, the nitrogen content in the silicon oxynitride powder after nitridation and the structural characteristics of the silicon oxynitride crystal can be controlled. Specifically, the mass content of nitrogen in the prepared silicon oxynitride powder is 20 - 40%.

[0052] In some embodiments, silicon oxide is ball-milled in an oxygen atmosphere at 100-200 °C for 30-40 min and then preheated in an oxygen atmosphere at 300-400 °C for 2-3 h. In fact, during the ball-milling process, the particle uniformity of the silicon oxide powder can be further improved, and at the same time, the defects on the surface of the silicon oxide can be increased, thereby further enhancing the surface activity of the silicon oxide. Ball-milling at 100-200 °C can form an oxide layer on the surface of the silicon oxide and improve its activity, which is conducive to the diffusion of nitrogen atoms and the formation of silicon oxynitride.

[0053] In some embodiments, the silicon oxynitride powder is surface-activated in an active agent. In fact, the silicon oxynitride powder can be surface-activated in an active solution containing the active agent. Specifically, the active agent includes at least one of cetyltrimethylammonium chloride, lauryldimethylamine oxide, and octadecyldimethylbenzylammonium chloride.

[0054] In fact, when the silicon oxynitride powder is surface-activated in an active solution containing the active agent, conventional treatment steps such as ultrasonic dispersion, oscillating dispersion, and stirring dispersion can be used to promote the uniform dispersion of the silicon oxynitride powder in the active solution. In addition, the solvent in the active solution is required to be able to dissolve the active agent and not react with the silicon oxynitride powder.

[0055] In some embodiments, after the silicon oxynitride powder is surface-activated, it is stirred and dispersed in tetraethyl orthosilicate at a solid-liquid ratio of 0.1-0.3 g / mL, which is beneficial to improving the dispersibility of the silicon oxynitride powder in tetraethyl orthosilicate, avoiding agglomeration and sedimentation of the silicon oxynitride powder in tetraethyl orthosilicate, and facilitating the coating modification of tetraethyl orthosilicate on the surface of the silicon oxynitride.

[0056] In some embodiments, the surface-activated silicon oxynitride powder is stirred and dispersed in tetraethyl orthosilicate, then separated and washed, and dried at 80-100 °C to obtain a pre-modified product. This is beneficial to the hydrolysis of tetraethyl orthosilicate on the surface of the silicon oxynitride powder to form a silicon dioxide coating structure.

[0057] In some embodiments, nano-molybdenum sulfide is surface-hydroxyl modified in an alkaline solution, where the solute of the alkaline solution includes one of sodium hydroxide and potassium hydroxide, and the average particle size of the nano-molybdenum sulfide used is 1-100 nm. In fact, during the hydroxyl modification process, hydroxide ions can react with metal ions on the surface of the nano-molybdenum sulfide to form a metal hydroxide layer and introduce hydroxyl functional groups, which can improve the dispersibility of the nano-molybdenum sulfide and its mechanical properties in the glaze layer.

[0058] In some embodiments, the modified molybdenum disulfide nanosheets and the modification precursor are ultrasonically mixed in absolute ethanol. Ultrasonic mixing in absolute ethanol helps to remove impurities mixed on the surfaces of the molybdenum disulfide nanosheets and the modification precursor, and also helps the molybdenum disulfide nanosheets and the modification precursor to be uniformly compounded. In fact, the mass ratio of the molybdenum disulfide nanosheets to the modification precursor is 1:(20 - 25).

[0059] In fact, when preparing the modified silicon oxynitride powder by re-nitriding the modified intermediate, the following steps are included: the modified intermediate is kept at a temperature of 1400 - 1500 °C in a nitrogen or ammonia atmosphere for 5 - 10 h, then vacuum degassed and cooled and ground to obtain the modified silicon oxynitride powder. In fact, the re-nitriding treatment can improve the surface structure of the modified material and introduce the element on the inner surface of the modified intermediate, thereby effectively improving the dispersibility of the modified silicon oxynitride powder in the glaze layer and enhancing the structural stability of the modified silicon oxynitride powder.

[0060] In some embodiments, the base glaze layer is sintered and formed on the tile body from the base glaze material. By mass, the base glaze material includes: 20 - 30 parts of alumina, 50 - 55 parts of silica, 2 - 3 parts of potassium oxide, 10 - 15 parts of alumina, 10 - 15 parts of calcium oxide, 1 - 2 parts of magnesium oxide, 1 - 2 parts of sodium oxide, 1 - 2 parts of zinc oxide, 1 - 2 parts of sodium carboxymethyl cellulose, and 1 - 2 parts of sodium hexametaphosphate.

[0061] In some embodiments, the top glaze layer is sintered and formed on the base glaze layer from the top glaze material. By mass, the top glaze material includes: 15 - 20 parts of alumina, 55 - 60 parts of silica, 2 - 3 parts of potassium oxide, 10 - 15 parts of alumina, 10 - 15 parts of calcium oxide, 1 - 2 parts of magnesium oxide, 1 - 2 parts of sodium oxide, 1 - 2 parts of zinc oxide, 1 - 2 parts of cesium oxide, 1 - 2 parts of sodium carboxymethyl cellulose, and 1 - 2 parts of sodium hexametaphosphate.

[0062] The present invention also provides a preparation process for the skin-friendly glaze ceramic tile, including the following steps: spraying the protective glaze material on the surface of the top glaze layer, and performing high-temperature sintering at 1200 - 1300 °C and then grinding and forming to obtain the skin-friendly glaze ceramic tile; the spraying amount of the protective glaze material on the surface of the top glaze layer is 300 - 400 g / m 2 。

[0063] In fact, when preparing the skin-friendly glaze ceramic tile, it is necessary to pre-press and dry the tile blank, then add the base glaze material to the tile blank, then add the top glaze material on the surface of the base glaze material, and finally add the protective glaze material and perform unified sintering and forming in the kiln.

[0064] Preparation Example 1

[0065] This Preparation Example 1 provides a preparation method for the modified silicon oxynitride powder, including the following steps:

[0066] S0. Silica with an average particle size of 5 μm is ball-milled in an oxygen atmosphere at 150 °C for 30 min using zirconia as the milling balls and a ball-to-material ratio of 20:1. After ball-milling, the silica is transferred to an oxygen atmosphere at 350 °C and preheated for 3 h.

[0067] S1. The preheated silica powder is placed in an atmosphere furnace with a nitrogen flow rate of 5 L / min. The furnace is heated to 1450 °C at a rate of 5 °C / min and held for 20 h, then cooled to 250 °C with the furnace and evacuated for 2 h for degassing. After grinding and pulverizing to an average particle size of 10 μm, it is cooled to room temperature to obtain silicon oxynitride powder. Elemental analysis shows that the mass content of nitrogen in the silicon oxynitride powder is 35.74%.

[0068] S2. The silicon oxynitride powder is ultrasonically dispersed in an ethanol solution of cetyltrimethylammonium chloride (CAS: 112-02-7; the mass ratio of silicon oxynitride powder to cetyltrimethylammonium chloride is 1:0.15) at a frequency of 20 kHz for 15 min, then held in a 45 °C water bath for 1 h, and then separated, washed, and dried to complete the surface activation of the silicon oxynitride powder.

[0069] S3. The surface-activated silicon oxynitride powder is added to tetraethyl orthosilicate at a solid-liquid ratio of 0.2 g / mL, ultrasonically treated at a frequency of 20 kHz for 15 min, held in a 50 °C water bath for 15 min, then filtered, separated, washed, and dried in a hot air dryer at 100 °C to constant weight to obtain a modified precursor.

[0070] S4. Nanoscale molybdenum sulfide with an average particle size of 20 nm is added to a saturated sodium hydroxide solution at a solid-liquid ratio of 0.2 g / mL, ultrasonically treated at a frequency of 30 kHz for 10 min, then stirred and mixed for 1 h, separated, and dried to constant weight in a 50 °C vacuum environment to complete the surface hydroxyl modification of the nanoscale molybdenum sulfide.

[0071] S5. The surface-hydroxyl-modified nanoscale molybdenum sulfide and the modified precursor are mixed at a mass ratio of 1:22 and added to absolute ethanol. They are ultrasonically mixed at a frequency of 30 kHz for 30 min, then separated and dried to obtain a modified intermediate. The modified intermediate is transferred to an atmosphere furnace, held in a nitrogen atmosphere at 1450 °C for 6 h, then vacuum degassed and cooled to room temperature, and then ground to obtain modified silicon oxynitride powder with an average particle size of 10 μm.

[0072] Preparation Example 2

[0073] This Preparation Example 2 provides a method for preparing modified silicon oxynitride powder, including the following steps:

[0074] S0. Silica with an average particle size of 5 μm is ball-milled in an oxygen atmosphere at 150 °C for 30 min using zirconia as the milling balls and a ball-to-material ratio of 20:1. After ball-milling, the silica is transferred to an oxygen atmosphere at 350 °C and preheated for 3 h;

[0075] S1. The preheated silica powder is placed in a muffle furnace with a nitrogen flow rate of 6 L / min. The furnace is heated to 1450 °C at a rate of 5 °C / min and held for 20 h, then cooled to 250 °C with the furnace and evacuated for 2 h of degassing. After grinding and pulverizing to an average particle size of 10 μm, it is cooled to room temperature to obtain silicon oxynitride powder. Elemental analysis shows that the mass content of nitrogen in the silicon oxynitride powder is 37.18%;

[0076] S2. The silicon oxynitride powder is ultrasonically dispersed in an ethanol solution of cetyltrimethylammonium chloride (CAS: 112 - 02 - 7; the mass ratio of silicon oxynitride powder to cetyltrimethylammonium chloride is 1:0.15) at a frequency of 20 kHz for 15 min, then held in a 45 °C water bath for 1 h, and then separated, washed, and dried to complete the surface activation of the silicon oxynitride powder;

[0077] S3. The surface-activated silicon oxynitride powder is added to tetraethyl orthosilicate at a solid-liquid ratio of 0.2 g / mL, ultrasonically treated at a frequency of 20 kHz for 15 min, then held in a 50 °C water bath for 15 min, filtered, separated, washed, and dried in a hot air dryer at 100 °C to constant weight to obtain a modified precursor;

[0078] S4. Nanoscale molybdenum sulfide with an average particle size of 20 nm is added to a saturated sodium hydroxide solution at a solid-liquid ratio of 0.2 g / mL, ultrasonically treated at a frequency of 30 kHz for 10 min, then stirred and mixed for 1 h, separated, and dried to constant weight in a 50 °C vacuum environment to complete the surface hydroxyl modification of the nanoscale molybdenum sulfide;

[0079] S5. The surface-hydroxyl-modified nanoscale molybdenum sulfide and the modified precursor are mixed at a mass ratio of 1:22 and added to absolute ethanol. After ultrasonic mixing at a frequency of 30 kHz for 30 min, they are separated, dried, and ground to obtain modified silicon oxynitride powder with an average particle size of 10 μm.

[0080] Preparation Example 3

[0081] This Preparation Example 3 provides a method for preparing modified silicon oxynitride powder, including the following steps:

[0082] S0. Silica with an average particle size of 5 μm is ball-milled in an oxygen atmosphere at 150 °C for 30 min using zirconia as the milling balls and a ball-to-material ratio of 20:1. After ball-milling, the silica is transferred to an oxygen atmosphere at 350 °C and preheated for 3 h;

[0083] S1. Place the preheated silicon oxide powder in an atmosphere furnace with a nitrogen flow rate of 5 L / min. The atmosphere furnace is heated to 1450 °C at a rate of 5 °C / min and then held for 20 h. After cooling to 250 °C with the furnace, it is evacuated for degassing for 2 h, ground and pulverized to an average particle size of 10 μm, and then cooled to room temperature to obtain the modified silicon oxynitride powder. The mass content of nitrogen in the modified silicon oxynitride powder is 35.74% as determined by elemental analysis.

[0084] Examples 1 to 5

[0085] Examples 1 to 5 respectively provide a protective glaze, and the mass parts of the chemical composition are shown in Table 1 below.

[0086] Table 1 Chemical composition of the protective glaze in Examples 1 to 5

[0087] Example 1 Example 2 Example 3 Example 4 Example 5 Silica 50 55 60 54 56 Aluminum Oxide 7 8 10 8 9 Boron Oxide 1 1.5 2 1.3 1.4 Sodium Oxide 2 2.3 3 2.5 2.4 Potassium Oxide 1 1.6 2 1.7 1.8 Calcium Oxide 15 17 20 16 17 Magnesium Oxide 1 1.6 2 1.4 1.2 Lithium Oxide 1 1.7 2 1.8 1.4 Cesium Oxide 0.1 0.3 0.5 0.4 0.3 Barium Oxide 0.1 0.4 0.5 0.3 0.4 Zinc Oxide 1 1.8 2 1.7 1.2 Modified Silicon Oxynitride Powder 1 1.7 2 1.4 1.5 Sodium Carboxymethyl Cellulose 1 1.4 2 1.3 1.8 Sodium Hexametaphosphate 1 1.3 2 1.2 1.6

[0088] Among them, the modified silicon oxynitride powder used in Examples 1 to 3 is the one prepared in Preparation Example 1, the modified silicon oxynitride powder used in Example 4 is the one prepared in Preparation Example 2, and the modified silicon oxynitride powder used in Example 5 is the one prepared in Preparation Example 3.

[0089] Comparative Example 1

[0090] Comparative Example 1 provides a protective glaze, which is different from Example 2 in that no modified silicon oxynitride powder is added in Comparative Example 1.

[0091] Comparative Example 2

[0092] Comparative Example 2 provides a protective glaze, which is different from Example 2 in that no modified silicon oxynitride powder is added in Comparative Example 2, and 1.7 parts of nano molybdenum sulfide are added instead.

[0093] Application Examples 1 to 7

[0094] Application Example 1 provides a method for preparing a skin glaze ceramic tile, which includes the following steps:

[0095] Y1. Prepare the bottom glaze, and its chemical composition includes 27 parts of alumina, 53 parts of silica, 2.5 parts of potassium oxide, 14 parts of alumina, 12 parts of calcium oxide, 1.2 parts of magnesium oxide, 1.6 parts of sodium oxide, 1.5 parts of zinc oxide, 1.1 parts of sodium carboxymethyl cellulose and 1.5 parts of sodium hexametaphosphate by mass.

[0096] Y2. Configure the surface glaze. The chemical components include 19 parts of alumina, 58 parts of silica, 2.3 parts of potassium oxide, 12 parts of alumina, 14 parts of calcium oxide, 1.5 parts of magnesium oxide, 1.6 parts of sodium oxide, 1.2 parts of zinc oxide, 1.5 parts of cesium oxide, 1.4 parts of sodium carboxymethyl cellulose, and 1.4 parts of sodium hexametaphosphate by mass.

[0097] Y3. After spraying the body glaze, surface glaze, and protective glaze (prepared in Examples 1 to 5 and Comparative Examples 1 to 2 respectively) on the surface of the ceramic tile body in sequence, transfer it to a kiln for high-temperature sintering at 1284 °C, and then perform edge grinding to obtain the skin glaze ceramic tile.

[0098] Performance testing

[0099] Use a WGG60 - Y4 type glossmeter to detect the surface gloss of the skin glaze ceramic tiles prepared in Application Examples 1 to 7. The test results are shown in Table 2 below. After grinding the surface of the skin glaze ceramic tiles 7500 times with a wear-resistant testing machine, observe the surface effect of the tiles and calculate the gloss attenuation rate, as shown in Table 2 below.

[0100] Table 2 Surface performance testing of skin glaze ceramic tiles

[0101] Gloss Before Polishing (°) Gloss Attenuation Rate (%) Effect of Brick Surface After Polishing Application Example 1 29.4 2.38 No Obvious Trace Application Example 2 31.5 2.24 No Obvious Trace Application Example 3 31.9 2.31 No Obvious Trace Application Example 4 29.7 8.67 No Obvious Trace Application Example 5 30.6 12.76 Slight Trace Application Example 6 31.5 24.51 Obvious Trace Application Example 7 32.8 13.84 Slight Trace

[0102] It can be seen from Table 2 that the surface gloss of the skin glaze ceramic tiles provided by the present invention is between 25 - 35 degrees, and the gloss attenuation rate meets the requirements after grinding. This shows that the skin glaze ceramic tiles provided by the present invention can be used well in the indoor environment for a long time, and there will be no significant decrease in surface gloss and no matte appearance due to long-term use.

[0103] It can be seen from Table 2 that in Application Example 4, the surface re-nitriding of the modified silicon oxynitride powder used in the protective glaze was not carried out, which to a certain extent affected the microscopic integrity of the surface of the protective glaze layer after being subjected to high-intensity grinding, thus affecting the surface gloss after grinding. In Application Example 5, the modified silicon oxynitride powder used in the protective glaze was not compounded with molybdenum disulfide nanoparticles, which affected the surface strength of the protective glaze layer. In Application Example 6, the modified silicon oxynitride powder was not added, and the wear resistance and gloss retention performance of the protective glaze layer decreased significantly. This shows the necessity of the modified silicon oxynitride powder in the protective glaze layer, and directly adding molybdenum disulfide nanoparticles in Application Example 7 can improve the wear resistance compared with Application Example 6.

[0104] Although the embodiments of the present invention have been described in detail above, it will be obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are all within the scope and spirit of the present invention as described in the claims. Moreover, the present invention as described herein may have other embodiments and can be implemented or realized in various ways.

Claims

1. A skin glaze ceramic tile, characterized in that: It includes a ceramic tile body and a skin glaze layer sintered and formed on at least one surface of the ceramic tile body, wherein the skin glaze layer includes a bottom glaze layer, a surface glaze layer and a protective glaze layer sequentially formed along the ceramic tile body; The protective glaze layer is sintered on the surface glaze layer by protective glaze, and the protective glaze comprises, by mass, 50-60 parts of silicon dioxide, 7-10 parts of aluminum oxide, 1-2 parts of boron oxide, 2-3 parts of sodium oxide, 1-2 parts of potassium oxide, 15-20 parts of calcium oxide, 1-2 parts of magnesium oxide, 1-2 parts of lithium oxide, 0.1-0.5 parts of cesium oxide, 0.1-0.5 parts of barium oxide, 1-2 parts of zinc oxide, 1-2 parts of modified silicon oxynitride powder, 1-2 parts of adhesive and 1-2 parts of dispersant; the preparation method of the modified silicon oxynitride powder comprises: after surface activation of silicon oxynitride powder, stirring and dispersing in tetraethyl orthosilicate, and then separating to obtain a modified precursor; after surface hydroxyl modification of nano-molybdenum sulfide, ultrasonically mixing and dispersing with the modified precursor, and then separating and drying to obtain a modified intermediate; and nitriding the modified intermediate to obtain the modified silicon oxynitride powder.

2. The skin-glazed ceramic tile according to claim 1, characterized in that: The adhesive includes at least one of sodium carboxymethyl cellulose, polyvinyl alcohol, sodium silicate, methyl cellulose, and sodium alginate; and / or the dispersant includes at least one of sodium polypropylene alcohol, sodium hexametaphosphate, and ethylenediamine di-o-hydroxyphenyl acetate; and / or the average particle size of the modified silicon oxynitride powder is 1-20 μm.

3. The skin glaze ceramic tile according to claim 1, characterized in that: The preparation method of silicon oxynitride powder comprises the following steps: preheating silicon oxide in an oxygen atmosphere at 300-400° C. for 2-3 hours, heating the preheated silicon oxide to 1400-1500° C. at a rate of 5-10° C. / min in a nitrogen atmosphere, keeping the temperature for 20-30 hours, vacuum degassing at 200-300° C. for 1-2 hours, and grinding to obtain silicon oxynitride powder.

4. The skin-glazed ceramic tile according to claim 3, characterized in that: The silicon oxide has a particle size of 1-10 μm; and / or, the nitrogen-containing atmosphere includes one of nitrogen and ammonia; and / or, the silicon oxide is ball-milled in an oxygen atmosphere at 100-200° C. for 30-40 minutes and then preheated in an oxygen atmosphere at 300-400° C. for 2-3 hours.

5. The skin-glazed ceramic tile according to claim 1, characterized in that: The mass content of nitrogen in the silicon oxynitride powder is 20-40%; and / or, the silicon oxynitride powder is surface activated in an active agent, and the active agent includes at least one of hexadecyltrimethylammonium chloride, lauryldimethylamine oxide, and octadecyldimethylbenzylammonium chloride; and / or, after the silicon oxynitride powder is surface activated, it is stirred and dispersed in tetraethyl orthosilicate at a solid-liquid ratio of 0.1-0.3g / mL; And / or, after stirring and dispersing in tetraethyl orthosilicate, separating and washing, and drying at 80-100° C., a modified precursor is obtained.

6. The skin-glazed ceramic tile according to claim 1, characterized in that: The average particle size of the nano-molybdenum sulfide is 1-100nm; and / or, the surface hydroxyl group of the nano-silicon sulfide is modified in an alkaline solution, and the solute in the alkaline solution includes one of sodium hydroxide and potassium hydroxide; and / or, when the surface of the nano-molybdenum sulfide is modified and then ultrasonically mixed with a modified precursor, the modified nano-molybdenum sulfide and the modified precursor are ultrasonically mixed in anhydrous ethanol; and / or, the mass ratio of the nano-molybdenum sulfide to the modified precursor is 1:(20-25).

7. The skin glaze ceramic tile according to claim 1, characterized in that: When the modified intermediate is subjected to complex nitridation to obtain the modified silicon oxynitride powder, the modified intermediate is kept warm in a nitrogen atmosphere or an ammonia atmosphere at 1400-1500° C. for 5-10 hours, and then vacuum degassed, cooled and ground to obtain the modified silicon oxynitride powder.

8. The skin-glazed ceramic tile according to claim 1, characterized in that: The base glaze layer is formed by sintering a base glaze material on the ceramic tile body, and the base glaze material includes, by mass, 20-30 parts of aluminum oxide, 50-55 parts of silicon dioxide, 2-3 parts of potassium oxide, 10-15 parts of aluminum oxide, 10-15 parts of calcium oxide, 1-2 parts of magnesium oxide, 1-2 parts of sodium oxide, 1-2 parts of zinc oxide, 1-2 parts of sodium carboxymethyl cellulose and 1-2 parts of sodium hexametaphosphate; and / or, the surface glaze layer is formed by sintering a surface glaze material on the base glaze layer, and the surface glaze material includes, by mass, 15-20 parts of aluminum oxide, 55-60 parts of silicon dioxide, 2-3 parts of potassium oxide, 10-15 parts of aluminum oxide, 10-15 parts of calcium oxide, 1-2 parts of magnesium oxide, 1-2 parts of sodium oxide, 1-2 parts of zinc oxide, 1-2 parts of cesium oxide, 1-2 parts of sodium carboxymethyl cellulose and 1-2 parts of sodium hexametaphosphate.

9. A process for preparing the skin glaze ceramic tile according to any one of claims 1 to 8, characterized in that: The following steps are involved: The protective glaze is sprayed on the surface of the glaze layer, and then sintered at 1200-1300°C and polished to form a skin glaze ceramic tile; the spraying amount of the protective glaze on the surface of the glaze layer is 300-400g / m 2 .