A decorative ceramic slab with crystal-like outline effect and its preparation method

Abstract

This invention discloses a crystal-outlined decorative ceramic slab and its preparation method. The preparation method includes the following steps: applying a first glaze to the surface of a brick blank; inkjet printing an oil-based spreading ink onto the surface of the brick blank after applying the first glaze; applying a second glaze to the surface of the brick blank after inkjet printing the oil-based spreading ink; the second glaze being spread by the oil-based spreading ink to form an undulating texture with grooves; inkjet printing a pattern onto the surface of the brick blank after applying the second glaze; strategically applying colored transparent frit to the surface of the brick blank after inkjet printing the pattern so that the colored transparent frit fills the grooves; applying a transparent glaze to the surface of the brick blank after strategically applying the colored transparent frit and firing it. After firing, the colored glass phase layer formed by the colored transparent frit contrasts with the opaque glaze layer around the grooves and the transparent glaze layer obtained by firing the transparent glaze on the glaze surface, thus obtaining the crystal-outlined decorative ceramic slab.

Description

Technical Field

[0001] This invention relates to a decorative ceramic slab with a crystal-outline effect and its preparation method, belonging to the field of ceramic tile production and manufacturing technology. Background Technology

[0002] Currently, there are many types of glazed ceramic tiles and slabs on the market. In order to improve product competitiveness, ceramic manufacturers are not only committed to enriching the color and pattern selection of their products, but also to increasing the added value of their products through various means.

[0003] Chinese patent CN113183292A discloses a method for preparing CNC mold-effect ceramic tiles. The method involves designing a mold pattern using a computer and then using a ceramic inkjet printer to print functional inks with spreading or scattering properties onto a flat tile blank, achieving a natural undulating effect. Chinese patent CN110668792A discloses a three-dimensional iridescent dry-granule polished ceramic slab and its preparation method, which achieves a smooth glaze surface by sprinkling dry-granule frit on the glaze surface and firing it. However, the decorative effects of the above products are limited and lack special additional decorative value. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a decorative ceramic slab with a crystal-outline effect and its preparation method. In this method, the groove is filled with a colored transparent molten block. After firing, the colored transparent molten block in the groove will form a colored glass phase. The area around the colored transparent molten block is an opaque glaze layer, and the upper layer is a transparent glaze layer. Under these conditions, the glaze effect creates a contrast, and the surface appears to have a multi-layered, undulating texture and a crystal-clear decorative effect.

[0005] In a first aspect, the present invention provides a method for preparing a ceramic slab with a crystal-outlined effect. The preparation method includes the following steps:

[0006] Apply the first glaze to the surface of the brick blank;

[0007] Inkjet printing of oil-based ink was applied to the surface of the brick after the first glaze was applied.

[0008] A second glaze is applied to the surface of the brick blank after inkjet printing of oil-based ink; the second glaze is spread by the oil-based ink to form an undulating texture with grooves.

[0009] Inkjet printing of patterns on the surface of the brick after the second glaze has been applied;

[0010] After the inkjet-printed pattern is applied to the surface of the brick blank, a colored transparent frit is positioned and sprinkled so that the colored transparent frit fills the grooves.

[0011] After the colored transparent frit is applied to the surface of the brick blank, a transparent glaze is applied and fired. After firing, the colored glass phase layer formed by the colored transparent frit contrasts with the opaque glaze layer around the groove and the transparent glaze layer obtained by firing the transparent glaze on the glaze surface, thus obtaining the crystal outline effect decorative ceramic slab.

[0012] Preferably, the initial melting temperature of the first glaze and / or the second glaze is 1170–1190°C.

[0013] Preferably, the chemical composition of the first glaze and / or the second glaze includes, by mass percentage: SiO2: 54-56%, Al2O3: 23-26%, alkaline earth metal oxides: 0.6-1.2%, alkali metal oxides: 7.3-9.0%, and ZrO2: 4.9-6.5%.

[0014] Preferably, the first glaze is applied by spraying, with a specific gravity of 1.30–1.35 g / cm³. 3 The glaze application amount is 300-320g / m². 2 .

[0015] Preferably, the second glaze is applied by spraying, with a specific gravity of 1.55–1.57 g / cm³. 3 The glaze application amount is 650-680 g / m². 2 .

[0016] Preferably, the amount of colored glass frit applied is 400–500 g / m³. 2 .

[0017] Preferably, the transparent frit contained in the transparent glaze has the following chemical composition by mass percentage: SiO2: 63-66%, Al2O3: 11-14%, CaO: 11-13%, MgO: 1-2%, K2O: 4.2-5.1%, Na2O: 0.2-0.5%, ZnO: 1.8-2.3%.

[0018] Preferably, the transparent glaze is applied by pouring, with an application rate of 1000–1200 g / m³. 2 .

[0019] Secondly, the present invention also provides a crystal-outlined decorative ceramic slab obtained by any of the preparation methods described above. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the crystal-outlined decorative ceramic slab of the present invention; wherein, 1 is the brick blank layer, 2 is the surface glaze layer, 3 is the colored transparent frit layer, and 4 is the transparent glaze layer.

[0021] Figure 2It is a cross-sectional view showing the effect of the glaze layer being peeled away;

[0022] Figure 3 This is a magnified view of the defect at the location of the transparent molten metal in Comparative Example 1;

[0023] Figure 4 This is a cross-sectional view of the low-density glaze in Comparative Example 2. Detailed Implementation

[0024] The present invention is further illustrated by the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention. Unless otherwise specified, all percentage contents refer to mass percentage contents.

[0025] The following exemplifies the preparation method of the crystal-outlined decorative ceramic slab of the present invention. "Outlined" refers to the line shape formed by the undulating texture.

[0026] The ceramic matrix is ​​pressed into brick blanks. The chemical composition of the ceramic matrix is ​​not limited; commonly used ceramic matrix formulations in the art can be used. In some embodiments, the chemical composition of the ceramic matrix includes, by mass percentage: SiO2: 62-67%, Al2O3: 20-25%, alkaline earth metal oxides: 0.2-2%, alkali metal oxides: 4-7%. For example, the chemical composition of the ceramic matrix includes, by mass percentage: SiO2: 62-67%, Al2O3: 20-25%, Fe2O3: 0.06-0.1%, TiO2: 0.1-0.5%, CaO: 0.1-0.5%, MgO: 0.1-1.0%, K2O: 2.0-3.0%, Na2O: 2.5-3.5%, and loss on ignition: 4.5-6.5%.

[0027] Brick blanks can be prepared by dry pressing. The brick blanks can be flat blanks.

[0028] Dry the brick blanks. For example, use a drying kiln. The drying time can be 1 to 1.2 hours, and the moisture content of the dried brick blanks should be controlled below 0.5 wt%.

[0029] Apply the first glaze to the dried brick surface. The purpose of the first glaze is to cover the base color and imperfections of the brick, promote inkjet printing, and prevent the oil-based ink from directly contacting the brick and exposing the base color. Simultaneously, the first glaze buffers the rising air bubbles from the area where the color-transparent frit (also called color frit) is applied. This is because once the color-transparent frit forms a liquid phase, it is difficult for gas to escape from the brick. At this point, the glaze layer has not yet formed a molten liquid, and there are many voids, thus storing the gas released from the brick. Since the brick has a low moisture content and poor surface flatness after leaving the drying kiln, applying the first glaze also helps improve flatness. Furthermore, the dried brick is at a high temperature, so when subsequent inkjet printing of oil-based ink is applied to the first glaze surface, the glaze layer has already dried, so the first glaze will not repel the ink and create a spreading effect.

[0030] The first glaze is a low-temperature glaze. In some embodiments, the initial melting temperature of the first glaze is 1170–1190°C.

[0031] The chemical composition of the first glaze includes, by mass percentage: SiO2: 54–56%, Al2O3: 23–26%, alkaline earth metal oxides: 0.6–1.2%, alkali metal oxides: 7.3–9.0%, and ZrO2: 4.9–6.5%. The zirconium oxide content in the first glaze should not be too low; otherwise, the glaze will have a yellowish tint, which is detrimental to the color development of inkjet patterns. As an example, the chemical composition of the first glaze includes, by mass percentage: Loss on ignition: 4.00–5.00%, SiO2: 54.89–55.78%, Al2O3: 23.87–25.45%, Fe2O3: 0.21–0.41%, TiO2: 0.06–0.08%, CaO: 0.55–0.87%, MgO: 0.18–0.29%, K2O: 4.89–5.62%, Na2O: 2.58–3.34%, P2O5: 0.21–0.40%, ZrO2: 4.96–6.35%, ZnO: 0.07–0.10%.

[0032] The first glaze is applied by spraying. In some embodiments, the specific gravity of the first glaze is 1.30–1.35 g / cm³. 3 The glaze application amount is 300-320g / m². 2 Applying the first glaze using a thin spraying method results in a high degree of smoothness. However, applying too much of the first glaze will lead to an excessively thick overall glaze layer, prolonging the upward emission cycle of gas from the brick and hindering the timely release of gas. This can result in a large number of air bubbles in the top transparent glaze layer.

[0033] Oil-based splatter ink is printed onto the surface of the brick after the first glaze is applied. An effect mesh can be created using a design vector graphic based on the layout, and the oil-based splatter ink is then printed according to this effect mesh to obtain the texture pattern. In some embodiments, the desired design pattern is processed, and the textures and curves in the design pattern are extracted by tracing a path, creating a design vector file corresponding to the design pattern. The processed design file is uploaded to a digital inkjet printer. After the brick has undergone the first glaze application, it enters the position of the digital inkjet printer, which sprays oil-based splatter ink according to the processed design pattern. The area covered by the oil-based splatter ink corresponds to the textures and curves of the design pattern. The composition and source of the oil-based splatter ink are not limited; commonly used oil-based splatter inks in the art can be used.

[0034] Before printing with oil-based ink, the surface temperature of the brick blank can be controlled at 35-40℃. Of course, drying is not necessary after printing with oil-based ink.

[0035] A second glaze is applied to the surface of the brick after inkjet printing with an oil-based spreading ink. The second glaze can be peeled away by the oil-based spreading ink to form a textured, grooved surface. Preferably, the second glaze has the same formulation as the first glaze to improve compatibility between the glaze layers.

[0036] The chemical composition of the second glaze includes, by mass percentage: SiO2: 54-56%, Al2O3: 23-26%, alkaline earth metal oxides: 0.6-1.2%, alkali metal oxides: 7.3-9.0%, and ZrO2: 4.9-6.5%. As an example, the chemical composition of the second glaze includes, by mass percentage: Loss on ignition: 4.00–5.00%, SiO2: 54.89–55.78%, Al2O3: 23.87–25.45%, Fe2O3: 0.21–0.41%, TiO2: 0.06–0.08%, CaO: 0.55–0.87%, MgO: 0.18–0.29%, K2O: 4.89–5.62%, Na2O: 2.58–3.34%, P2O5: 0.21–0.40%, ZrO2: 4.96–6.35%, ZnO: 0.07–0.10%.

[0037] Preferably, the initial melting temperature of the second glaze is 1170–1190°C.

[0038] The experiment found that if the first and second glazes use high-temperature glazes, the color pigments themselves have a low melting point, and they will form molten liquid before the glaze reaches its melting point. At this time, the glaze layers are not sealed. Due to the large temperature difference between the melting temperature of the glaze layer and the color pigment, the color frit layer is sealed after it forms molten liquid, but the glaze layer still has large gaps, which causes the gas in the brick body to continuously escape and rise through the glaze layer. A large amount of gas will break through the transparent frit layer, resulting in a large number of craters.

[0039] The second glaze is applied by spraying. In some embodiments, the specific gravity of the second glaze is 1.55–1.57 g / cm³. 3 The glaze application amount is 650-680 g / m². 2 Within this range, the glaze layer acts as a buffer for the air release of the brick body. At the same time, the higher glaze application of the second glaze makes the spreading effect more obvious, with significant groove details and texture in the spread area. If the glaze application of the second glaze is lower, the spreading will be more flat, unable to present the undulating texture, and it will not be conducive to the color flocs filling the grooves.

[0040] The control of the second glaze in this invention corresponds to the vector diagram of the oil-based spreading ink. If the vector diagram is mainly composed of fine lines and spots, the amount of glaze applied to the second glaze can be appropriately reduced to avoid reducing the groove effect. This is because the amount of oil-based spreading ink used is small at this time, and the spreading is subject to greater resistance.

[0041] The pattern is printed using inkjet printing on the surface of the brick after the second glaze has been applied. The texture and color of the inkjet-printed pattern are adapted to the layout design. Digital inkjet printers can be used. Ceramic inks available include blue, brown, orange, lemon yellow, black, and red.

[0042] After inkjet printing the pattern, colored transparent frit is applied to the surface of the brick blank to fill the grooves. Specifically, adhesive is first applied to the surface of the inkjet-printed brick blank. The adhesive is applied to the areas of the grooves where color decoration is needed (i.e., the areas where colored transparent frit is applied). A digital adhesive applicator can be used for the application of adhesive. The adhesive material is not particularly limited and can be any adhesive known in the art. After applying the adhesive, colored transparent frit is applied to the surface of the brick blank. The application method for the colored transparent frit can be a digital dry pelletizer and / or a belt feeder. It can be dispersed using a vibrating screen, and excess material can be recycled using a recovery device, leaving only the areas that need decoration.

[0043] The application rate of the transparent colored frit can be 400-500 g / m³. 2Using this amount of frit maximizes the distribution of the colored transparent frit in the grooves, ensuring that the grooves are filled with colored frit. Then, excess colored transparent frit is removed, allowing the colored crystal decoration to be applied only to the grooves. Removal methods can include blowing or extracting. For example, a recovery exhaust fan can be used to remove excess colored frit.

[0044] The colored transparent frit comprises, by weight, 100 parts of transparent frit and 1-2 parts of glaze colorant. For example, the colored transparent frit is obtained by dry mixing the transparent frit and the glaze colorant. The chemical composition of the transparent frit comprises, by mass percentage: SiO2: 63-66%, Al2O3: 11-14%, CaO: 11-13%, MgO: 1-2%, K2O: 4.2-5.1%, Na2O: 0.2-0.5%, ZnO: 1.8-2.3%. As an example, the chemical composition of the transparent frit includes, by mass percentage: Loss on ignition: 0.23–0.25%, SiO2: 63.00–65.90%, Al2O3: 11.00–13.95%, CaO: 11.00–13.00%, Fe2O3: 0.05–0.20%, TiO2: 0.05–0.10%, MgO: 1.00–2.00%, K2O: 4.21–5.10%, Na2O: 0.23–0.35%, ZnO: 1.80–2.30%. The glaze colorants are adapted to meet decorative color requirements.

[0045] The colored transparent frit contains a large amount of pigment, resulting in a relatively low overall melting point (initial melting temperature). If a large amount is applied to the surface of the transparent glaze, the frit will be encapsulated by the glaze, easily forming pinholes on the glaze surface. The preparation method of this invention not only solves the problem of product defects caused by the low melting point of the colored transparent frit leading to the formation of numerous bubbles after encapsulation, but also separates the colored transparent frit layer from other glaze layers to create decorative layers, and resolves the cracking phenomenon in the glaze layers due to inconsistent coefficients of thermal expansion.

[0046] Apply a transparent glaze to the surface of the brick blank after the colored transparent frit has been applied in a targeted manner.

[0047] The transparent glaze is a calcined glaze containing transparent frit. Preferably, the transparent frit in the color and the transparent frit in the transparent glaze are from the same formulation system, which reduces glaze cracking caused by differences in the glaze layers. Compared to raw transparent glaze, transparent glaze containing transparent frit forms fewer bubbles in the glaze layer, which is beneficial for improving the overall transparency of the glaze layer. In some embodiments, the chemical composition of the transparent frit contained in the transparent glaze includes, by mass percentage: SiO2: 63-66%, Al2O3: 11-14%, CaO: 11-13%, MgO: 1-2%, K2O: 4.2-5.1%, Na2O: 0.2-0.5%, ZnO: 1.8-2.3%. As an example, the chemical composition of the transparent frit includes, by mass percentage: Loss on ignition: 0.23–0.25%, SiO2: 63.00–65.90%, Al2O3: 11.00–13.95%, CaO: 11.00–13.00%, Fe2O3: 0.05–0.20%, TiO2: 0.05–0.10%, MgO: 1.00–2.00%, K2O: 4.21–5.10%, Na2O: 0.23–0.35%, ZnO: 1.80–2.30%. The glaze colorants are adapted to meet decorative color requirements.

[0048] The transparent glaze contains transparent frit with a particle size of 80-250 mesh.

[0049] The initial melting temperature of the aforementioned transparent glaze is 920–1030℃. Most minerals in the brick body undergo carbonate decomposition at 900–950℃, producing a large amount of gas. Controlling the initial melting temperature of the transparent glaze within this range avoids excessive temperature differences between decorative layers, preventing the timely release of gas from the brick body and thus avoiding defects. In some embodiments, the initial melting temperature of the surface glaze is 160–260℃ higher than that of the transparent glaze.

[0050] In addition to the transparent frit, the transparent glaze also includes water and glaze adhesive. In some embodiments, the transparent glaze comprises, by weight, 45-52 parts of transparent frit, 8-12 parts of water, and 38-43 parts of glaze adhesive. The transparent glaze can be applied by pouring.

[0051] The amount of the transparent glaze applied is 1000-1200 g / m³. 2 Because diffusion occurs at the transparent molten areas, in order to separate the layers between the transparent glaze layers, applying a large amount of transparent glaze within a certain effective range can help separate the glaze layers, resulting in a transparent glaze layer above the colored decorative area.

[0052] Dry the brick blanks after applying the transparent glaze. An electric kiln can be used for drying. The drying temperature is 110–120℃, and the moisture content of the dried brick blanks should be controlled below 0.3 wt%.

[0053] Firing. For example, it is slow-fired at a low temperature in a roller kiln. To promote bubble removal, a slow-firing process is adopted to ensure mirror finish and transparency. For example, the firing cycle is 107–110 minutes. The maximum firing temperature (temperature of the measuring ring) is 1154–1161℃, and correspondingly, the maximum firing temperature (kiln surface temperature) is 1210–1220℃.

[0054] The preparation method described in this invention, through process innovation, utilizes a combination of colored transparent frit, a transparent glaze layer, and a textured finish to create a unique decorative effect. Because the recessed areas are filled with colored transparent frit, after firing, the colored transparent frit in the recesses forms a colored glassy phase. The periphery of the colored transparent frit is an opaque glaze layer, and the upper layer is a transparent glaze layer. Under these conditions, the glaze effect creates a contrast, resulting in a multi-layered, textured surface with a crystal-clear decorative effect. In some embodiments, the dimensions of the slab are 1800–3600 mm in length × 900–1800 mm in width × 10.5–12.5 mm in thickness.

[0055] The following examples further illustrate the present invention in detail. It should also be understood that the following examples are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below.

[0056] Example 1

[0057] The preparation method of the crystal-outlined decorative ceramic slab includes the following steps:

[0058] Step 1. Press ordinary ceramic base material into brick blanks;

[0059] Step 2. Dry the brick blanks in a drying kiln for 1 to 1.2 hours, and control the moisture content of the dried blanks to within 0.5 wt%.

[0060] Step 3. Apply the first glaze to the surface of the brick blank; the chemical composition of the first glaze includes, by mass percentage: loss on ignition: 4.00–5.00%, SiO2: 54.89–55.78%, Al2O3: 23.87–25.45%, Fe2O3: 0.21–0.41%, TiO2: 0.06–0.08%, CaO: 0.55–0.87%, MgO: 0.18–0.29%, K2O: 4.89–5.62%, Na2O: 2.58–3.34%, P2O5: 0.21–0.40%, ZrO2: 4.96–6.35%, ZnO: 0.07–0.10%; the specific gravity of the first glaze is 1.30–1.35 g / cm³. 3 Glazing amount 300-320g / m 2 ;

[0061] Step 4. Inkjet print an oil-based inkjet printer onto the surface of the brick after the first glaze has been applied;

[0062] Step 5. Apply a second glaze to the surface of the brick blank after the inkjet-printed oil-based ink has been removed. The chemical composition of the second glaze includes, by mass percentage: Loss on ignition: 4.00–5.00%, SiO2: 54.89–55.78%, Al2O3: 23.87–25.45%, Fe2O3: 0.21–0.41%, TiO2: 0.06–0.08%, CaO: 0.55–0.87%, MgO: 0.18–0.29%, K2O: 4.89–5.62%, Na2O: 2.58–3.34%, P2O5: 0.21–0.40%, ZrO2: 4.96–6.35%, ZnO: 0.07–0.10%; the specific gravity of the second glaze is 1.55–1.57 g / cm³. 3 The glaze application amount is 650-680 g / m². 2 ;

[0063] Step 6. Inkjet print a pattern on the surface of the brick after the second glaze has been applied;

[0064] Step 7. Apply colored transparent frit to the surface of the brick blank after inkjet printing pattern using a digital glue dry pellet machine, leaving colored frit only in the grooves, and remove the excess colored transparent frit.

[0065] Step 8. Apply a transparent glaze to the surface of the brick blank after spreading the colored transparent frit; the transparent glaze contains a transparent frit with the following chemical composition by mass percentage: Loss on ignition: 0.23-0.25%, SiO2: 63.00-65.90%, Al2O3: 11.00-13.95%, CaO: 11.00-13.00%, Fe2O3: 0.05-0.20%, TiO2: 0.05-0.10%, MgO: 1.00-2.00%, K2O: 4.21-5.10%, Na2O: 0.23-0.35%, ZnO: 1.80-2.30%; the application rate of the transparent glaze is 1000-1200 g / m². 2 ;

[0066] Step 9. Dry the brick blanks after applying the transparent glaze at a temperature of 110-120℃. After drying, the moisture content of the brick blanks should be controlled to be less than 0.3wt%.

[0067] Step 10. The product is placed in the roller kiln for low-temperature slow firing. The firing cycle is 107-110 minutes, and the maximum firing temperature (temperature of the measuring ring) is 1154-1161℃. Correspondingly, the maximum firing temperature (temperature displayed on the kiln surface) is 1210-1220℃.

[0068] The crystal-outline decorative ceramic slab obtained in this embodiment has colored transparent frit filling the groove. After firing, the colored transparent frit in the groove will form a colored glass phase. The area around the colored transparent frit is an opaque glaze layer, and the upper layer is a transparent glaze layer. Under these conditions, the glaze effect creates a contrast, and the surface appears to have a multi-layered texture and a crystal-clear decorative effect.

[0069] Comparative Example 1

[0070] The process is essentially the same as in Example 1, except that the chemical composition of the first and / or second glazes includes, by mass percentage: Loss on ignition: 3.82%, SiO2: 50.58%, Al2O3: 33.69%, Fe2O3: 0.21%, TiO2: 0.08%, CaO: 1.20%, MgO: 1.45%, K2O: 4.27%, Na2O: 2.13%, ZrO2: 2.49%, ZnO: 0.08%. The initial melting temperature of the glaze layer is relatively high. After the transparent glaze layer is completely closed, the brick blank has already released air upwards through the glaze layer, resulting in numerous crater-like defects in the transparent glaze layer decorated with colored flocs. The defective effect is as follows... Figure 3 As shown.

[0071] Comparative Example 2

[0072] This is essentially the same as Example 1, except that the specific gravity of the second glaze is less than 1.40 g / m³. 3Because the surface glaze has a relatively high water content, the glaze dries slowly on both sides of the oil-based ink, making it difficult for the ink to peel off the glaze. The peeling effect of the oil-based ink is smooth, lacking a three-dimensional texture, and is not conducive to the filling of transparent color blocks. Its peeling effect is as follows: Figure 4 .

Claims

1. A method for preparing a decorative ceramic slab with a crystal-outlined effect, characterized in that, The preparation method includes the following steps: Apply the first glaze to the surface of the brick blank; Inkjet printing of oil-based ink was applied to the surface of the brick after the first glaze was applied. A second glaze is applied to the surface of the brick blank after inkjet printing of oil-based ink; the second glaze is spread by the oil-based ink to form an undulating texture with grooves. Inkjet printing of patterns on the surface of the brick after the second glaze has been applied; After the inkjet-printed pattern is applied to the surface of the brick blank, a colored transparent frit is positioned and sprinkled so that the colored transparent frit fills the grooves. After the colored transparent frit is applied to the surface of the brick blank, a transparent glaze is applied and fired. After firing, the colored glass phase layer formed by the colored transparent frit contrasts with the opaque glaze layer around the groove and the transparent glaze layer obtained by firing the transparent glaze on the glaze surface, thus obtaining the crystal outline effect decorative ceramic slab.

2. The preparation method according to claim 1, characterized in that, The initial melting temperature of the first glaze and / or the second glaze is 1170–1190℃.

3. The preparation method according to claim 1, characterized in that, The chemical composition of the first glaze and / or the second glaze includes, by mass percentage: SiO2: 54%–56%, Al2O3: 23%–26%, alkaline earth metal oxides: 0.6%–1.2%, alkali metal oxides: 7.3%–9.0%, ZrO2: 4.9%–6.5%.

4. The preparation method according to claim 1, characterized in that, The first glaze is applied by spraying, with a specific gravity of 1.30–1.35 g / cm³. 3 The glaze application amount is 300-320g / m². 2 .

5. The preparation method according to claim 1, characterized in that, The second glaze is applied by spraying, with a specific gravity of 1.55–1.57 g / cm³. 3 The glaze application rate is 650–680 g / m². 2 .

6. The preparation method according to claim 1, characterized in that, The application rate of the colored transparent frit is 400–500 g / m³. 2 .

7. The preparation method according to claim 1, characterized in that, The transparent glaze contains a transparent frit with the following chemical composition by mass percentage: SiO2: 63%–66%, Al2O3: 11%–14%, CaO: 11%–13%, MgO: 1%–2%, K2O: 4.2%–5.1%, Na2O: 0.2%–0.5%, ZnO: 1.8%–2.3%.

8. The preparation method according to claim 1, characterized in that, The transparent glaze is applied by pouring, with an application rate of 1000–1200 g / m³. 2 .

9. The preparation method according to claim 1, characterized in that, The firing process is low-temperature slow firing; the firing cycle is 107-110 minutes.

10. A decorative ceramic slab with a crystal-outline effect obtained by the preparation method according to any one of claims 1 to 9.

Images