A method for preparing ceramic bricks with double-layer slip and the ceramic bricks themselves.

Abstract

This invention provides a method for preparing ceramic tiles with two layers of slip and the ceramic tiles themselves. The method for preparing ceramic tiles with two layers of slip includes: preparing a first slip according to a first slip raw material formula, and preparing a second slip according to a second slip raw material formula; applying the first slip to a pre-prepared ceramic body to obtain a first slip layer; applying the second slip to the ceramic body with the first slip layer applied to it to obtain a second slip layer; and processing the ceramic body with the first and second slip layers to obtain the ceramic tile. This invention, by preparing two slip slurries, adjusts the single-layer glazing process to a two-layer thin glaze process, solving the "orange peel" problem in glazing, improving glaze smoothness, and reducing the zirconium silicate content in the overall glaze, thus reducing production costs.

Description

Technical Field

[0001] This invention relates to the field of ceramic production technology, and in particular to a method for preparing ceramic bricks with a double-layer slip and the ceramic bricks themselves. Background Technology

[0002] In recent years, the ceramic tile industry has faced the challenge of simultaneously improving product quality and reducing production costs. Popular products like "golden velvet" and "delicate glaze" require a high degree of glaze smoothness. To achieve this, some production lines incorporate a polishing process before applying slip, smoothing the surface of the dried ceramic body. However, this polishing process presents two problems: first, it easily generates dust, hindering environmental control; second, as dust concentration increases within the polishing equipment, fine powder accumulates on the polishing blocks, which, if not cleaned promptly, can damage the surface, leading to pinholes in the glaze. Furthermore, for fully polished glazed products, the smoothness of the glaze surface after firing directly affects polishing quality and efficiency. Better glaze smoothness reduces the incidence of defects such as rough surfaces; it also facilitates faster and more efficient polishing processes.

[0003] Currently, the general process for producing glazed tiles involves first applying a layer of slip to the surface of the tile body, then printing patterns using inkjet printing, and finally applying a layer of transparent glaze. The whiteness of the slip plays a crucial role in the representation of the pattern texture, especially for marble-like products. The whiteness of the slip is one of the key factors in expressing the details of the texture; the higher the whiteness of the slip, the clearer the texture details and the closer it is to the texture of natural stone. However, considering cost, the whiteness of the tile body is currently mostly controlled at 20-30 degrees. To achieve a whiteness of over 60 degrees for the semi-finished product after applying slip, the slip needs to have a stronger covering ability for the tile body. To improve the covering ability of the slip for the tile body, one way is to increase the content of the opacifier zirconium silicate in the formula. However, zirconium silicate is expensive, thus increasing costs. Another way is to increase the thickness of the slip without changing the formula. However, when applying a thicker slip glaze, its water absorption rate is slower, which can easily produce an "orange peel" phenomenon on the glaze surface, affecting the smoothness after glazing.

[0004] Therefore, existing technologies have shortcomings and need to be improved and developed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for preparing ceramic bricks with double-layer slip and ceramic bricks, in order to address the above-mentioned defects of the prior art. The aim is to solve the problems in the prior art where some methods increase costs and others affect the flatness after glazing in order to improve the covering ability of slip on the body.

[0006] The technical solution adopted by this invention to solve the technical problem is as follows:

[0007] The first aspect of this application provides a method for preparing ceramic bricks with a double-layer slip, comprising:

[0008] The first cosmetic clay was prepared according to the first cosmetic clay raw material formula, and the second cosmetic clay was prepared according to the second cosmetic clay raw material formula.

[0009] The first slip is applied to a pre-prepared ceramic blank to obtain a first slip layer;

[0010] A second slip is applied to the ceramic blank on which a first slip layer has been applied, to obtain a second slip layer;

[0011] Ceramic bricks are obtained by processing ceramic blanks with a first slip layer and a second slip layer applied.

[0012] Based on the above-mentioned technical means, this application embodiment prepares two types of slip slurry to adjust the slip glazing process from a one-time glazing process to a two-time thin glaze glazing process, which solves the "orange peel" problem of glazing and improves the smoothness of glazing; and reduces the zirconium silicate content in the overall glaze, thereby reducing production costs.

[0013] In one embodiment of this application, the formulation of the first slip material is different from that of the second slip material. The first slip material is a high-spherical-base, high-tailings, zirconium-free formulation system slip material, and the second slip material is a high-nepheline formulation system slip material.

[0014] Based on the above-mentioned technical means, this application embodiment prepares two types of slip slurry, which improve the smoothness of glaze application.

[0015] In one embodiment of this application, the first cosmetic clay raw material formula contains ≥20% kaolin by weight, ≥60% industrial tailings sand by weight, and 0% zirconium-containing material by weight. The second cosmetic clay raw material formula contains ≥40% nepheline by weight. The raw materials of the first cosmetic clay formula include: potassium feldspar, calcined talc, kaolin, and industrial tailings sand.

[0016] Based on the above technical means, in order to further reduce the formula cost, the embodiments of this application introduce industrial tailings into the first cosmetic clay raw material formula, and there are no zirconium-containing raw materials, thereby reducing the glaze cost while ensuring the product's brick shape, whiteness and other indicators.

[0017] In one embodiment of this application, the raw materials in the first cosmetic clay formula, by weight, include:

[0018] Potassium feldspar 4-6 parts, calcined talc 5-7 parts, kaolin 20-27 parts, industrial tailings sand 60-70 parts;

[0019] The ingredients in the second cosmetic clay formula, by weight, include:

[0020] Potassium feldspar 8-10 parts, zirconium silicate 10-18 parts, calcined talc 1-3 parts, quartz 10-15 parts, wollastonite 5-10 parts, kaolinite 8-10 parts, alumina 0-3 parts, nepheline 40-45 parts.

[0021] Based on the above-mentioned technical means, the embodiments of this application recycle and utilize inexpensive industrial tailings sand raw materials, which have a high firing temperature. By adjusting the sintering degree of the formula through fluxes such as talc, the amount of industrial tailings sand can reach 70%, reducing the formula cost. At the same time, it turns waste into treasure and reduces the environmental pollution caused by tailings landfill, which has good economic and environmental benefits.

[0022] In one embodiment of this application, the chemical components of the first cosmetic clay raw material formulation, by mass percentage, include:

[0023] Loss on ignition 2%–4%, SiO2 68%–72%, Al2O3 16%–18%, Fe2O3 0–0.3%, CaO 0–1%, MgO 2%–3%, K2O 2%–3%, Na2O 3%–4%;

[0024] The chemical components of the second cosmetic clay raw material formula, by mass percentage, include:

[0025] Loss on ignition 3%–4%, SiO2 52%–60%, Al2O3 15%–20%, Fe2O3 0–0.25%, CaO 3%–5%, MgO 1%–1.5%, K2O 2%–3%, Na2O 4%–5%, ZrO2 7%–10%.

[0026] Based on the above-mentioned technical means, the first cosmetic clay raw material formula provided in this application embodiment brings many benefits such as improved physical properties, optimized chemical stability, improved process performance, and environmental protection and sustainability.

[0027] In one embodiment of this application, the whiteness value of each individual raw material in the first slip clay formula after sintering is 68-70 degrees, and the glazing amount of the first slip clay is 295-310 g / m³. 2 The first slip layer has a whiteness value of 40-50 degrees, a thickness of 0.08-0.1 mm, and a gloss level of 3.5-5 degrees after sintering; the second slip layer has a glaze application rate of 360-380 g / m². 2The whiteness of the second slip layer is 50-60 degrees, the thickness of the second slip layer is 0.12-0.15 mm, the gloss of the second slip layer after sintering is 4-6 degrees, the whiteness of the first slip layer and the second slip layer combined is 66-76 degrees, the thickness of the first slip layer and the second slip layer combined is 0.2-0.25 mm, and the gloss of the first slip layer and the second slip layer combined is 4-6 degrees.

[0028] Based on the above-mentioned technical means, the embodiments of this application can ensure that a cosmetic clay layer with better flatness and whiteness is obtained.

[0029] In one embodiment of this application, preparing a first cosmetic clay according to a first cosmetic clay raw material formula and preparing a second cosmetic clay according to a second cosmetic clay raw material formula includes:

[0030] According to the formula for the first cosmetic clay, each raw material is put into a ball mill, water is added and the mixture is ground for 4 to 6 hours. After iron removal, sieving and aging, the first cosmetic clay is obtained.

[0031] The fineness of the first slip is 0.4% to 0.6% residue on a 325-mesh sieve, the specific gravity is 1.70 to 1.75, and the Engler viscosity is 33 to 36S.

[0032] According to the formula for the second cosmetic clay, each raw material is put into a ball mill, water is added and the mixture is ground for 5 to 6 hours. After iron removal, sieving and aging, the second cosmetic clay is obtained.

[0033] The second cosmetic clay has a fineness of 0.4% to 0.5% residue on a 325-mesh sieve, a specific gravity of 1.78 to 1.82, and an Engler viscosity of 28 to 32S.

[0034] In one embodiment of this application, the ceramic body temperature is 80-90°C, the ceramic body travels at a speed of 50 m / min between the application of the first and second slips, and the distance between the glazing position of the first and second slips is 12-18 m.

[0035] According to the above technical means, when applying the second slip, there are no obvious traces of moisture on the surface of the brick when viewed from the side. This ensures that the moisture in the first slip has been basically evaporated and absorbed by the brick body, and the brick body maintains a certain level of moisture. This avoids the situation where the distance is too short, and the second slip is applied directly before the moisture in the first slip on the brick body has been completely evaporated and absorbed, which would cause the product to have an orange peel defect. It also avoids the situation where the distance is too long, and the first slip has dried completely, resulting in an overly dry surface of the brick body with insufficient moisture, which would easily lead to pinhole defects.

[0036] In one embodiment of this application, a ceramic blank with a first slip layer and a second slip layer applied is processed to obtain a ceramic brick, comprising:

[0037] A pattern decoration process is performed on a ceramic blank with a first slip layer and a second slip layer to obtain a decorated blank.

[0038] After applying a transparent polished glaze to the surface of the decorated blank, it is fired at high temperature in a kiln to obtain ceramic bricks.

[0039] Based on the above-mentioned technical means, the embodiment of this application divides the conventional single layer of slip used in the production of ceramic tiles into two layers, which are applied in small amounts multiple times. This reduces the amount of glaze applied each time, making it easier for the body to absorb. After the two layers of slip are stacked, the glaze layer is smoother, improving the production quality of the product. This avoids the situation where a large amount of slip is applied at once, resulting in a thick glaze layer and slow glaze slurry drying, which can lead to the orange peel phenomenon. Furthermore, the first layer of slip is a high-ball soil, high-tailings, zirconium-free formula slip, which consumes a large amount of industrial tailings sand and reduces the use of expensive zirconium silicate raw materials. These multiple measures greatly reduce production costs.

[0040] A second aspect of this application provides a ceramic brick, wherein the ceramic brick is prepared by the method for preparing ceramic bricks with double-layer slip as described above.

[0041] The present invention achieves the following beneficial effects:

[0042] First, the embodiments of this application utilize inexpensive industrial tailings sand raw materials, which have a relatively high firing temperature. By adjusting the sintering degree of the formula through fluxes such as talc, the amount of industrial tailings used can reach 70%, reducing the formula cost. At the same time, it turns waste into treasure and reduces the environmental pollution caused by tailings landfill, thus having good economic and environmental benefits.

[0043] Secondly, this application's embodiment innovates the slip glazing process by changing from applying a single, thick glaze coat to two thinner coats. Because the glaze slurry has a high water content, when a single, thick slip coat is applied, the water absorption rate is slow, easily resulting in an "orange peel" effect on the glaze surface, affecting the smoothness of the glazed product. When two thinner coats are applied, the first thinner slip coat absorbs water quickly, forming water molecule channels. The second thinner slip coat also absorbs water quickly after being applied, ensuring a smooth glaze. Therefore, the smoothness of the glaze is better after two coats.

[0044] Third, the overall glaze application amount of the slip in this application embodiment is increased, the flatness is improved, which is more conducive to the control of brick shape deformation of polished glazed tiles, and at the same time provides a basis for reducing the amount of glaze application for transparent glaze with a smaller coefficient of expansion.

[0045] Fourth, in addition to economic benefits, the embodiments of this application effectively improve the smoothness of the glaze surface, which has a positive effect on improving product quality and polishing efficiency. Attached Figure Description

[0046] Figure 1 This is a flowchart of a preferred embodiment of a method for preparing ceramic bricks with double-layer slip in this invention.

[0047] Figure 2 This is a detailed process flowchart of a preferred embodiment of a method for preparing ceramic bricks with double-layer slip in this invention. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0049] Slip can cover rough, uneven, and dark-colored areas on the surface of ceramic bodies, making the surface of ceramic products smoother, flatter, and more aesthetically pleasing. The use of slip can make the upper glaze appear more vibrant, facilitate coloring, and enhance the decorative effect of ceramic products. Furthermore, slip can improve the quality of the glaze, making the glaze layer appear beautiful, glossy, soft, and lustrous.

[0050] Please see Figure 1 , Figure 1 This is a flowchart of the preparation method of the ceramic brick with double-layer slip in this invention. For example... Figure 1 As shown, the method for preparing ceramic bricks with double-layer slip as described in this embodiment of the invention includes the following steps:

[0051] Step S100: Prepare the first cosmetic clay according to the first cosmetic clay raw material formula, and prepare the second cosmetic clay according to the second cosmetic clay raw material formula.

[0052] In this embodiment, the formulation of the first slip material is different from that of the second slip material. The first slip material is a high-spherical-base, high-tailings, zirconium-free formulation system slip material, and the second slip material is a high-nepheline formulation system slip material, or it can be a conventional slip material formulation.

[0053] Specifically, to ensure the color development of the printing ink, the formula for the second slip (i.e., the slip that comes into direct contact with the inkjet ink) remains unchanged; to consider cost and whiteness, the expensive zirconium silicate can be removed from the first slip, and raw materials with higher whiteness are preferred. The two slips are ball-milled, iron-removed, sieved, and aged according to the formula to obtain a qualified slip glaze.

[0054] This application embodiment prepares two types of slip slurry to adjust the slip glazing process from a single-layer glazing process to a two-layer thin glaze process, solving the "orange peel" problem of glazing and improving the smoothness of the glaze; and also reduces the zirconium silicate content in the overall glaze, thus reducing production costs.

[0055] In this embodiment of the application, the first cosmetic clay raw material formula contains ≥20% kaolin by weight, ≥60% industrial tailings sand by weight, and 0% zirconium-containing material by weight. The second cosmetic clay raw material formula contains ≥40% nepheline by weight. The raw materials of the first cosmetic clay formula include: potassium feldspar, calcined talc, kaolin, and industrial tailings sand.

[0056] In one embodiment of this application, the raw materials in the first cosmetic clay formula, by weight, include: 4-6 parts potassium feldspar, 5-7 parts calcined talc, 20-27 parts kaolin, and 60-70 parts industrial tailings sand; the raw materials in the second cosmetic clay formula, by weight, include:

[0057] Potassium feldspar 8-10 parts, zirconium silicate 10-18 parts, calcined talc 1-3 parts, quartz 10-15 parts, wollastonite 5-10 parts, kaolinite 8-10 parts, alumina 0-3 parts, nepheline 40-45 parts.

[0058] This application embodiment recycles inexpensive industrial tailings sand raw materials, which have a high firing temperature. By adjusting the sintering degree of the formula with fluxes such as talc, the amount of industrial tailings sand used can reach 70%, reducing the formula cost. At the same time, it turns waste into treasure and reduces the environmental pollution caused by tailings landfill, which has good economic and environmental benefits.

[0059] In one embodiment of this application, the chemical components of the first cosmetic clay raw material formula, by mass percentage, include: 2%–4% loss on ignition, 68%–72% SiO2, 16%–18% Al2O3, 0%–0.3% Fe2O3, 0%–1% CaO, 2%–3% MgO, 2%–3% K2O, and 3%–4% Na2O; the chemical components of the second cosmetic clay raw material formula, by mass percentage, include: 3%–4% loss on ignition, 52%–60% SiO2, 15%–20% Al2O3, 0%–0.25% Fe2O3, 3%–5% CaO, 1%–1.5% MgO, 2%–3% K2O, 4%–5% Na2O, and 7%–10% ZrO2.

[0060] The first cosmetic clay raw material formula provided in this application embodiment brings many benefits, such as improved physical properties, optimized chemical stability, improved process performance, and environmental protection and sustainability.

[0061] In this embodiment, the whiteness value of each individual raw material in the first slip clay formula after sintering is 68-70 degrees, and the glazing amount of the first slip clay is 295-310 g / m³. 2The whiteness of the first slip layer is 40-50 degrees, the thickness of the first slip layer is 0.08-0.1 mm, the gloss of the first slip layer after sintering is 3.5-5 degrees, and the glaze application amount of the second slip layer is 360-380 g / m². 2 The second slip layer has a whiteness value of 50-60 degrees, a thickness of 0.12-0.15 mm, and a gloss of 4-6 degrees after sintering. The combined whiteness value of the first and second slip layers is 66-76 degrees, with a thickness of 0.2-0.25 mm and a gloss of 4-6 degrees. In other words, this embodiment not only introduces industrial tailings sand into the first slip layer but also ensures that the whiteness values ​​of the two slip layers are the same as, or even whiter than, those of conventional slip layers.

[0062] In one embodiment of this application, preparing a first cosmetic clay according to a first cosmetic clay raw material formula and preparing a second cosmetic clay according to a second cosmetic clay raw material formula includes:

[0063] According to the formula for the first cosmetic clay, each raw material is put into a ball mill, water is added and the mixture is ground for 4 to 6 hours. After iron removal, sieving and aging, the first cosmetic clay is obtained.

[0064] The fineness of the first slip is 0.4% to 0.6% residue on a 325-mesh sieve, the specific gravity is 1.70 to 1.75, and the Engler viscosity is 33 to 36S.

[0065] The second cosmetic clay was prepared according to the second cosmetic clay raw material formula, including:

[0066] According to the formula for the second cosmetic clay, each raw material is put into a ball mill, water is added and the mixture is ground for 5 to 6 hours. After iron removal, sieving and aging, the second cosmetic clay is obtained.

[0067] The second cosmetic clay has a fineness of 0.4% to 0.5% residue on a 325-mesh sieve, a specific gravity of 1.78 to 1.82, and an Engler viscosity of 28 to 32S.

[0068] Specifically, the raw materials are fed into a ball mill, water is added, and the milling process is carried out for 4–6 hours to obtain a slip slurry. The first slip does not contain zirconium silicate and has a higher kaolin content. The amount of water added during ball milling is greater than that of conventional slips. The fineness of the first slip is 0.4%–0.6% residue on a 325-mesh sieve, a specific gravity of 1.70–1.75, and an Engler viscosity of 33–36S. During iron removal and sieving, the milled slurry is filtered through a 100-mesh double-layer sieve. After iron removal in an iron removal trough, the slurry is pumped to a slurry tank for aging to obtain the first slip. To obtain a finer texture and thus higher whiteness, the second-stage slip is prepared by putting all the raw materials into a ball mill, adding water and grinding for 5-6 hours. After iron removal, sieving, and aging, the second slip is obtained. The fineness of the second slip is 0.4%-0.5% residue on a 325-mesh sieve, a specific gravity of 1.78-1.82, and an Engler viscosity of 28-32S. Of course, the preparation parameters of the second slip can also be controlled according to conventional production.

[0069] like Figure 1 As shown, the method for preparing ceramic bricks with double-layer slip as described in this embodiment of the invention further includes:

[0070] Step S200: Apply the first slip to the pre-prepared ceramic blank to obtain the first slip layer.

[0071] Specifically, the ceramic green body in this application is a green body produced by conventional ceramic brick production process, that is, the ceramic brick green body is obtained by conventional ceramic brick process and then used for later use.

[0072] In this embodiment of the application, the whiteness value of the first slip layer is 40-50 degrees, the gloss of the first slip layer after sintering is 3.5-5 degrees, the whiteness value of the second slip layer is 50-60 degrees, the gloss of the second slip layer after sintering is 4-6 degrees, and the whiteness value of the first slip layer + the second slip layer is 66-76 degrees.

[0073] Specifically, the first slip is prepared by ball milling according to the raw material formula, and then applied at a rate of 295–310 g / m² to the ceramic tile blank. 2 After the first slip is applied, it is fired. The whiteness of the first slip layer is measured to be 40-50 degrees. The thickness of the first slip layer is measured using an electron microscope and is 0.08-0.1 mm. The sintering degree of the first slip layer is characterized by a gloss meter measurement, and the gloss is 3.5-5 degrees. No pinholes are caused after firing. The second slip is then ball-milled into a slurry according to the formula, and applied at a rate of 360-380 g / m² to the ceramic tile blank. 2After the second slip is applied, the ceramic tile is fired. The whiteness of the second slip layer is measured to be 50–60 degrees. The thickness of the second slip layer is measured using an electron microscope and is 0.12–0.15 mm. The sintering degree of the second slip layer is characterized by a gloss meter measurement, and the gloss is 4–6 degrees. No pinholes are caused after firing. The first and second slip raw material formulas are ball-milled and slurries are prepared separately, and 295–310 g / m² of the slurry is applied to the ceramic tile blank. 2 After the first layer of cosmetic, apply 360-380g / m² of product. 2 The second layer of slip is fired, and the whiteness of the double-layer slip is measured to be 66-76 degrees. The thickness of the second slip layer is measured using an electron microscope and is 0.2-0.25 mm. The sintering degree of the double-layer slip layer is characterized by the gloss level measured by a gloss instrument and is 4-6 degrees.

[0074] The embodiments of this application can ensure that a smooth and whiter cosmetic layer is obtained.

[0075] like Figure 1 As shown, the method for preparing ceramic bricks with double-layer slip as described in this embodiment of the invention further includes:

[0076] Step S300: Apply the second slip to the ceramic blank on which the first slip layer has been applied, to obtain the second slip layer.

[0077] This invention adjusts the glazing process using slip, changing from applying one thick slip layer to applying two thinner slip layers. The first slip layer has a thickness of 0.08–0.1 mm after firing, and the second slip layer has a thickness of 0.12–0.15 mm after firing. The two slip layers are applied sequentially to the surface of the ceramic tile body, resulting in a total thickness of 0.2–0.25 mm after firing. This ensures that the overall thickness of the base glaze (0.2–0.25 mm) is greater than the previous thickness (0.18–0.22 mm), thus guaranteeing better smoothness and whiteness of the glaze. Specifically, the ceramic body temperature is 80-90℃, the brick-walking speed between the application of the first and second slips is 50m / min, and the distance between the first and second slip application positions is 12-18m. This ensures that when the second slip is applied, there are no obvious moisture marks on the brick surface when viewed under sidelight. This guarantees that the moisture in the first slip has been largely evaporated and absorbed by the body, maintaining a certain level of moisture in the body. This avoids situations where the distance is too short, causing the first slip on the brick to not be fully evaporated and absorbed before the second slip is applied, resulting in orange peel defects. It also avoids situations where the distance is too long, causing the first slip to dry completely, resulting in an overly dry surface and insufficient moisture, which can easily lead to pinhole defects.

[0078] This application's embodiment innovates the slip glazing process by changing from a single, thick glaze application to two thinner glaze applications. Because the glaze slurry has a high water content, when a single, thick slip layer is applied, the water absorption rate is slow, easily resulting in an "orange peel" effect on the glaze surface, affecting the smoothness of the glazed product. When two thinner glaze layers are applied, the first thin slip layer absorbs water quickly, forming water molecule channels, and the second thin slip layer also absorbs water quickly upon application, ensuring a smooth glaze surface. Therefore, the smoothness of the glaze after two applications is better. Thus, this application's embodiment improves the smoothness of the glaze surface, enhances the polishing effect, and increases polishing efficiency by increasing the overall glaze layer thickness.

[0079] Table 1 shows a comparison of the parameters between the first and second cosmetic layers obtained in this embodiment:

[0080] Table 1

[0081]

[0082] The linear expansion coefficient of the first slip layer in this embodiment is close to that of conventional slip, and has little impact on the brick shape. Furthermore, due to the increase in the total glaze thickness of the slip, the smoothness of the glaze surface is guaranteed, which further allows for a suitable reduction in the amount of transparent glaze with a smaller linear expansion coefficient. This has a positive effect on stabilizing the flatness and deformation of the product and reducing production costs.

[0083] In one embodiment, the total dry glaze weight of a conventional slip + conventional clear glaze solution is 636.4 g / m³. 2 The price of glaze is 1.5917 yuan / m³ 2 In this embodiment, the total dry weight of the first slip, second slip, and transparent glaze is 703.9 g / m³. 2 The price of glaze is 1.3457 yuan / m³ 2 Compared to the original product, the total dry glazing material of this invention increased by 10.6%, while the cost decreased by 15.45%. See Table 2 for details.

[0084] Table 2

[0085]

[0086] The smoothness of the glaze surface is expressed by the measurement value of a roughness instrument. A roughness instrument is used to measure the surface roughness of a product; the higher the measured value, the rougher the surface and the worse the smoothness. As shown in Table 3:

[0087] Table 3

[0088] Comparison parameters Roughness (μm) Original product: single-layer slip fired into glaze 3.647～4.165 This invention features a double-layer slip-fired glaze. 3.267～3.589 The original product was glazed with a transparent glaze and then fired to create a glazed surface. 1.528～1.865 The present invention applies a transparent glaze and then fires to form a glaze surface. 1.348～1.415

[0089] The comparison results of the brick type of the product of this invention and the original product are shown in Table 4:

[0090] Table 4

[0091]

[0092] like Figure 1 As shown, the method for preparing ceramic bricks with double-layer slip as described in this embodiment of the invention further includes:

[0093] Step S400: Process the ceramic blank with the first slip layer and the second slip layer to obtain ceramic brick.

[0094] In this embodiment of the application, step S400 specifically includes: performing pattern decoration treatment on a ceramic blank with a first slip layer and a second slip layer to obtain a decorated blank; applying a transparent polishing glaze to the surface of the decorated blank and then firing it at high temperature in a kiln to obtain a ceramic brick.

[0095] Specifically, the product is fired at high temperature in a kiln, and the surface may or may not be polished after firing to obtain ceramic tiles. A detailed process diagram is shown below. Figure 2 As shown.

[0096] This application embodiment divides the conventional single-layer slip layer used in the industry for producing ceramic tile products into two layers, applying them in small amounts multiple times. This reduces the amount of glaze applied each time, making it easier for the body to absorb. The double-layer slip layer results in a smoother glaze layer, improving product quality. It avoids the problem of applying a large amount of slip at once, resulting in a thick glaze layer and slow glaze drying, which can lead to an orange peel effect. Furthermore, the first layer of slip is a high-soil, high-tailings, zirconium-free formula slip system. This consumes a large amount of industrial tailings sand and reduces the use of expensive zirconium silicate raw materials. These multiple measures significantly reduce production costs.

[0097] The following are specific examples for illustration.

[0098] Example 1

[0099] Step A1: By weight, 4-6 parts of potassium feldspar, 6.3-6.8 parts of calcined talc, 23-25 ​​parts of kaolin, and 64-67 parts of industrial tailings sand are put into a ball mill, ground with water for 4-6 hours, and after iron removal, sieving, and aging, the first slip is obtained; the fineness of the first slip is 0.4%-0.6% residue on a 325-mesh sieve, the specific gravity is 1.70-1.75, and the Engler viscosity is 33-36S. Furthermore, by weight, 8-9 parts of potassium feldspar, 12-15 parts of zirconium silicate, 2-3 parts of calcined talc, 12-15 parts of quartz, 6-9 parts of wollastonite, 8-9 parts of kaolin, 2-3 parts of alumina, and 41-43 parts of nepheline are put into a ball mill, ground with water for 5-6 hours, and after iron removal, sieving, and aging, a second slip is obtained; the fineness of the second slip is 0.4%-0.5% residue on a 325-mesh sieve, the specific gravity is 1.78-1.82, and the Engler viscosity is 28-32S.

[0100] Step A2: Apply the first slip to the pre-prepared ceramic blank to obtain the first slip layer.

[0101] Step A3: Apply the second slip to the ceramic body on which the first slip layer has been applied to obtain the second slip layer;

[0102] Step A4: Perform pattern decoration treatment on the ceramic blank with the first slip layer and the second slip layer applied to obtain the decorated blank;

[0103] Step A5: After applying a transparent glaze to the surface of the decorated body, it is fired at high temperature in a kiln to obtain ceramic bricks.

[0104] Example 2

[0105] Step B1: By weight, 5 parts potassium feldspar, 6 parts calcined talc, 25 parts kaolin, and 60 parts industrial tailings sand are put into a ball mill, water is added and the mixture is ground for 4 hours. After iron removal, sieving, and aging, the first slip is obtained. The fineness of the first slip is 0.4% to 0.6% residue on a 325-mesh sieve, the specific gravity is 1.70 to 1.75, and the Engler viscosity is 34 to 35S. Furthermore, by weight, 8 parts of potassium feldspar, 12 parts of zirconium silicate, 3 parts of calcined talc, 13 parts of quartz, 9 parts of wollastonite, 9 parts of kaolin, 3 parts of alumina, and 43 parts of nepheline were put into a ball mill, ground with water for 6 hours, and after iron removal, sieving, and aging, a second slip was obtained. The fineness of the second slip was 0.4%-0.5% residue on a 325-mesh sieve, the specific gravity was 1.78-1.82, and the Engler viscosity was 28-30S.

[0106] Step B2: Apply the first slip to the pre-prepared ceramic blank to obtain the first slip layer.

[0107] Step B3: Apply the second slip to the ceramic body on which the first slip layer has been applied to obtain the second slip layer;

[0108] Step B4: Perform pattern decoration treatment on the ceramic blank with the first slip layer and the second slip layer applied to obtain the decorated blank;

[0109] Step B5: After applying a transparent polished glaze to the surface of the decorated body, it is fired at high temperature in a kiln to obtain ceramic bricks.

[0110] Example 3

[0111] Step C1: By weight, 6 parts potassium feldspar, 7 parts calcined talc, 20 parts kaolin, and 66 parts industrial tailings sand are put into a ball mill, ground with water for 5 hours, and after iron removal, sieving, and aging, the first slip is obtained; the fineness of the first slip is 0.4% to 0.5% residue on a 325-mesh sieve, the specific gravity is 1.72 to 1.75, and the Engler viscosity is 35 to 36S. Furthermore, by weight, 10 parts potassium feldspar, 10 parts zirconium silicate, 2 parts calcined talc, 12 parts quartz, 8 parts wollastonite, 10 parts kaolin, 1 part alumina, and 40 parts nepheline were added to a ball mill and ground with water for 5 hours. After iron removal, sieving, and aging, a second slip was obtained. The second slip had a fineness of 0.4%-0.5% residue on a 325-mesh sieve, a specific gravity of 1.78-1.80, and an Engler viscosity of 29-31S.

[0112] Step C2: Apply the first slip to the pre-prepared ceramic blank to obtain the first slip layer.

[0113] Step C3: Apply the second slip to the ceramic body on which the first slip layer has been applied to obtain the second slip layer;

[0114] Step C4: Perform pattern decoration treatment on the ceramic blank with the first slip layer and the second slip layer applied to obtain the decorated blank;

[0115] Step C5: After applying a transparent polished glaze to the surface of the decorated body, it is fired at high temperature in a kiln to obtain ceramic bricks.

[0116] The embodiments of this application achieve the following effects:

[0117] First, the embodiments of this application utilize inexpensive industrial tailings sand raw materials, which have a relatively high firing temperature. By adjusting the sintering degree of the formula through fluxes such as talc, the amount of industrial tailings sand can reach 70%, reducing the formula cost. At the same time, it turns waste into treasure and reduces the environmental pollution caused by tailings landfill, thus having good economic and environmental benefits.

[0118] Secondly, this application's embodiment innovates the slip glazing process by changing from applying a single, thick glaze coat to two thinner coats. Because the glaze slurry has a high water content, when a single, thick slip coat is applied, the water absorption rate is slow, easily resulting in an "orange peel" effect on the glaze surface, affecting the smoothness of the glazed product. When two thinner coats are applied, the first thinner slip coat absorbs water quickly, forming water molecule channels. The second thinner slip coat also absorbs water quickly after being applied, ensuring a smooth glaze. Therefore, the smoothness of the glaze is better after two coats.

[0119] Third, the overall glaze application amount of the slip in this application embodiment is increased, the flatness is improved, which is more conducive to the deformation control of polished glazed tiles, and at the same time provides a basis for reducing the glaze application amount for transparent glaze with a smaller coefficient of expansion.

[0120] Fourth, in addition to economic benefits, the embodiments of this application effectively improve the smoothness of the glaze surface, which has a positive effect on improving product quality and polishing efficiency.

[0121] This application also provides a ceramic tile, wherein the ceramic tile is prepared by the method for preparing ceramic tiles with double-layer slip as described above.

[0122] This invention provides a method for preparing ceramic tiles with two layers of slip and the ceramic tiles themselves. The method for preparing ceramic tiles with two layers of slip includes: preparing a first slip according to a first slip raw material formula, and preparing a second slip according to a second slip raw material formula; applying the first slip to a pre-prepared ceramic body to obtain a first slip layer; applying the second slip to the ceramic body with the first slip layer applied to it to obtain a second slip layer; and processing the ceramic body with the first and second slip layers to obtain the ceramic tile. This invention, by preparing two slip slurries, adjusts the single-layer glazing process to a two-layer thin glaze process, solving the "orange peel" problem in glazing, improving glaze smoothness, and reducing the zirconium silicate content in the overall glaze, thus reducing production costs.

[0123] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for preparing ceramic bricks with a double-layer slip, characterized in that, include: The first cosmetic clay was prepared according to the first cosmetic clay raw material formula, and the second cosmetic clay was prepared according to the second cosmetic clay raw material formula. The first slip is applied to a pre-prepared ceramic blank to obtain a first slip layer; A second slip is applied to the ceramic blank on which a first slip layer has been applied, to obtain a second slip layer; Ceramic bricks are obtained by processing ceramic blanks with a first slip layer and a second slip layer applied. The raw material formula of the first slip is different from that of the second slip. The first slip is a high-ball soil, high-tailings, zirconium-free formula slip, while the second slip is a high-nepheline formula slip.

2. The method for preparing ceramic bricks with double-layer slip according to claim 1, characterized in that, The first cosmetic clay raw material formula contains kaolin with a weight content of ≥20%, industrial tailings sand with a weight content of ≥60%, and zirconium-containing materials with a weight content of 0%. The second cosmetic clay raw material formula contains nepheline with a weight content of ≥40%.

3. The method for preparing ceramic bricks with double-layer slip according to claim 1, characterized in that, The ingredients in the first cosmetic clay formula, by weight, include: Potassium feldspar 4-6 parts, calcined talc 5-7 parts, kaolin 20-27 parts, industrial tailings sand 60-70 parts; The ingredients in the second cosmetic clay formula, by weight, include: Potassium feldspar 8-10 parts, zirconium silicate 10-18 parts, calcined talc 1-3 parts, quartz 10-15 parts, wollastonite 5-10 parts, kaolinite 8-10 parts, alumina 0-3 parts, nepheline 40-45 parts.

4. The method for preparing ceramic bricks with double-layer slip according to claim 1, characterized in that, The chemical components of the first cosmetic clay raw material formula, by mass percentage, include: Loss on ignition 2%~4%, SiO2 68%~72%, Al2O3 16%~18%, Fe2O3 0~0.3%, CaO 0~1%, MgO 2%~3%, K2O 2%~3%, Na2O 3%~4%; The chemical components of the second cosmetic clay raw material formula, by mass percentage, include: Loss on ignition 3%~4%, SiO2 52%~60%, Al2O3 15%~20%, Fe2O3 0~0.25%, CaO 3%~5%, MgO 1%~1.5%, K2O 2%~3%, Na2O 4%~5%, ZrO2 7%~10%.

5. The method for preparing ceramic bricks with double-layer slip according to claim 1, characterized in that, The whiteness value of each individual raw material in the first slip formula after sintering is 68-70 degrees, and the glaze application amount of the first slip is 295-310 g / m³. 2 The first slip layer has a whiteness value of 40-50 degrees, a thickness of 0.08-0.1 mm, and a gloss level of 3.5-5 degrees after sintering; the second slip layer has a glaze application rate of 360-380 g / m². 2 The whiteness of the second slip layer is 50-60 degrees, the thickness of the second slip layer is 0.12-0.15 mm, the gloss of the second slip layer after sintering is 4-6 degrees, the whiteness of the first slip layer and the second slip layer combined is 66-76 degrees, the thickness of the first slip layer and the second slip layer combined is 0.2-0.25 mm, and the gloss of the first slip layer and the second slip layer combined is 4-6 degrees.

6. The method for preparing ceramic bricks with double-layer slip according to claim 1, characterized in that, The first cosmetic clay is prepared according to the first cosmetic clay raw material formula, and the second cosmetic clay is prepared according to the second cosmetic clay raw material formula, including: According to the formula for the first cosmetic clay, each raw material is put into a ball mill, water is added and the mixture is ground for 4 to 6 hours. After iron removal, sieving and aging, the first cosmetic clay is obtained. The fineness of the first slip is 0.4%~0.6% residue on a 325-mesh sieve, the specific gravity is 1.70~1.75, and the Engler viscosity is 33~36S; According to the formula for the second cosmetic clay, each raw material is put into a ball mill, water is added and the mixture is ground for 5-6 hours. After iron removal, sieving and aging, the second cosmetic clay is obtained. The second cosmetic clay has a fineness of 0.4%~0.5% residue on a 325-mesh sieve, a specific gravity of 1.78~1.82, and an Engler viscosity of 28~32S.

7. The method for preparing ceramic bricks with double-layer slip according to claim 1, characterized in that, The ceramic body temperature is 80~90℃, the ceramic body travels at a speed of 50m / min between the application of the first and second slips, and the distance from the glazing position of the first slip to the glazing position of the second slip is 12~18m.

8. The method for preparing ceramic bricks with double-layer slip according to claim 1, characterized in that, The ceramic body with a first slip layer and a second slip layer is processed to obtain ceramic bricks, including: A pattern decoration process is performed on a ceramic blank with a first slip layer and a second slip layer to obtain a decorated blank. After applying a transparent polished glaze to the surface of the decorated blank, it is fired at high temperature in a kiln to obtain ceramic bricks.

9. A ceramic tile, characterized in that, The ceramic brick is prepared by the method for preparing ceramic bricks with double-layer slip as described in any one of claims 1 to 8.

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