A full polishing enamel, full polishing enamel ceramic tile and a preparation method thereof

Abstract

This invention belongs to the field of ceramic building materials, specifically relating to a fully polished glazed tile, a fully polished glazed ceramic tile, and its preparation method. The raw material composition of the fully polished glaze includes, by mass percentage: 40-50% albite, 15-20% clinker, 1-5% quartz, 1-4% calcined kaolin, 1-3% calcined alumina, 7-10% washed kaolin, 5-10% dolomite, 1-5% calcined talc, 1-3% calcite, 1-3% wollastonite, 1-4% zinc oxide, and 1-5% strontium carbonate. This invention solves the pinhole problem associated with the "volcano crater" shape.

Description

Technical Field

[0001] This invention belongs to the field of ceramic building materials, specifically relating to a fully polished glazed ceramic tile and its preparation method. Background Technology

[0002] There are many types of ceramic decorative effects. Fully polished glazed tiles, as a common type of decorative ceramic tile, are widely used in various decorative effects due to their rich patterns, affordable price, good stain resistance, and easy cleaning. They are used in large quantities and have a wide range of applications. The applicant, while ensuring product quality, is committed to reducing energy consumption to achieve low-temperature rapid firing, thereby achieving low carbon emissions and cost reduction and efficiency improvement. However, during the low-energy debugging process, multiple single pinholes appeared on the tile surface, shaped like "volcano craters," with a diameter of over 1.2mm. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a fully polished glazed ceramic tile and its preparation method, solving the pinhole problem associated with the "volcano-shaped" surface. The objective of this invention can be achieved through the following technical solutions:

[0004] In a first aspect, the present invention provides a fully polished glaze. The raw material composition of the fully polished glaze includes, by mass percentage: 40-50% albite, 15-20% clinker, 1-5% quartz, 1-4% calcined kaolin, 1-3% calcined alumina, 7-10% washed kaolin, 5-10% dolomite, 1-5% calcined talc, 1-3% calcite, 1-3% wollastonite, 1-4% zinc oxide, and 1-5% strontium carbonate.

[0005] Preferably, the raw material composition of the clinker includes, by mass percentage: 25-30% potassium feldspar, 7-12% sodium feldspar, 2-5% quartz, 1-4% aluminum hydroxide, 8-13% calcined kaolin, 7-15% washed kaolin, 10-15% dolomite, 4-7% calcite, 1-3% wollastonite, 2-3% zinc oxide, and 10-15% barium carbonate or barium sulfate.

[0006] Preferably, the clinker is prepared by: mixing ingredients according to the raw material composition of the clinker, adding water, sodium hydroxymethyl cellulose and sodium tripolyphosphate, and ball milling to prepare a glaze slurry; spray drying the glaze slurry into powder, pressing it into a blank, and then drying, firing and crushing it to obtain the clinker.

[0007] Preferably, the sodium carboxymethyl cellulose accounts for 0.25% to 0.35 wt% of the clinker raw material composition, and the sodium tripolyphosphate accounts for 0.4% to 0.5 wt% of the clinker raw material composition.

[0008] Preferably, the chemical composition of the fully polished glaze includes, by mass percentage: loss on ignition: 5-7%; SiO2: 53.5-55%; Al2O3: 14.5-16.3%; Fe2O3: 0.1-0.2%; TiO2: 0.01-0.2%; CaO: 6-8.5%; MgO: 2.5-3.3%; K2O: 0.5-1.2%; Na2O: 3.5-4.5%; ZnO: 3.3-3.9%; BaO: 1.5-2.0%; SrO: 2.5-3.0%.

[0009] Secondly, the present invention provides a method for preparing fully polished glazed ceramic tiles, comprising the following steps:

[0010] Brick blanks are obtained by pressing the raw material powder into shape.

[0011] Dry the brick blanks;

[0012] Apply a surface glaze to the dried brick blank;

[0013] Inkjet printing of patterns on the surface of the brick blank after the glaze has been applied;

[0014] Apply the full polished glaze described above to the surface of the brick blank after inkjet printing the pattern;

[0015] Fully polished glazed ceramic tiles are obtained by firing in a kiln and polishing.

[0016] Preferably, the full-polished glaze is applied by pouring glaze; the specific gravity of the full-polished glaze is 1.84–1.88 g / cm³. 3 The glaze application amount is 420-540 g / m². 2 .

[0017] Preferably, the firing temperature is 1210–1230°C and the firing cycle is 37–50 min.

[0018] Preferably, the chemical composition of the glaze comprises, by mass percentage: SiO2: 57.0–60.3%, Al2O3: 25.0–30%, Fe2O3: 0.1–0.2%, TiO2: 0.04–0.1%, CaO: 0.5–1.5%, MgO: 0.5–1.5%, K2O: 3.5–4.6%, Na2O: 2.1–3.5%, ZrO2: 4.1–6.0%; preferably, the glaze is applied by pouring; more preferably, the specific gravity of the glaze is 1.84–1.88 g / cm³. 3 The glaze application amount is 420-540 g / m². 2 .

[0019] Thirdly, the present invention provides fully polished glazed ceramic tiles obtained by any of the preparation methods described above.

[0020] Beneficial effects:

[0021] Creative approach: Prepare mature chemical materials with high burn-off values ​​and introduce them into the fully polished glaze, thereby reducing the amount of high burn-off materials used in the glaze, increasing the silicon and aluminum content of the glaze, and reducing the occurrence of pinholes in the glazed products.

[0022] Excellent decorative effect: The polished glaze of this invention can satisfy most dark and black products, and the products prepared with it have a good decorative effect. Especially when used on dark and black products, it increases the transparency and enhances the three-dimensionality of the product, realistically restoring the texture of marble.

[0023] Wide range of applications: This invention is not affected by environmental factors and can be widely used in various types of floor tile interior and exterior wall decoration.

[0024] Easy to clean: The porcelain glazed tiles prepared by this invention can be fully sintered, with a water absorption rate controlled within 0.04%, good layering, good stain resistance, and easy to clean.

[0025] Durable and long-lasting: This invention has stable performance, is less affected by time and environmental factors, has high wear resistance, can maintain a new feel for a long time, has a long service life, and has broad market economic benefits. Attached Figure Description

[0026] Figure 1 This is a rendering of the brick surface from Example 1;

[0027] Figure 2 This is a comparison of scale 1, showing the brick surface effect.

[0028] Figure 3 This is a comparison of scale 3, showing the brick surface effect.

[0029] Figure 4 This is a magnified view of the pinhole in Comparative Example 3;

[0030] Figure 5 This is a brick surface effect diagram at scale 4;

[0031] Figure 6 This is a scale 5 rendering of the brick surface.

[0032] Figure 7 This is a scaled-down rendering of the brick surface. Detailed Implementation

[0033] 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. The following exemplarily illustrates the preparation method of the fully polished glazed ceramic tile according to the present invention.

[0034] Brick blanks are obtained by pressing the green body powder into shape. The chemical composition and raw material composition of the green body powder are not limited; commonly used ceramic green body base materials in this field can be used. For example, the chemical composition of the green body powder may include, by mass percentage: SiO2: 60–65%, Al2O3: 20–25%, Fe2O3: 0.6–0.8%, TiO2: 0.1–0.4%, CaO: 0.2–0.6%, MgO: 0.2–0.6%, K2O: 2.0–3.5%, Na2O: 2.0–3.5%, and loss on ignition: 3.5–5.5%.

[0035] Dry the brick blanks. A drying kiln can be used. The drying temperature can be 150–240℃, and the drying time can be 50–60 minutes. The moisture content of the dried brick blanks should be controlled below 0.5 wt%.

[0036] A surface glaze is applied to the dried brick surface. The chemical composition of the surface glaze may include, by mass percentage: SiO2: 57.0–60.3%, Al2O3: 25.0–30%, Fe2O3: 0.1–0.2%, TiO2: 0.04–0.1%, CaO: 0.5–1.5%, MgO: 0.5–1.5%, K2O: 3.5–4.6%, Na2O: 2.1–3.5%, ZrO2: 4.1–6.0%. Besides covering the base color of the brick and aiding inkjet printing, the surface glaze also prevents the brick from warping or arching, promotes a smooth surface for the subsequent application of polished glaze, and ensures that the glaze is free of defects such as blistering or bubbles after firing.

[0037] In some embodiments, the raw material composition of the glaze includes, by mass percentage: potassium feldspar: 35-45%, sodium feldspar: 0-5%, nepheline: 13-20%, quartz: 15-22%, calcined alumina: 12-15%, calcined kaolin: 0-3%, washed kaolin: 7-9%, dolomite: 0-3%, calcined talc: 0-4%, and zirconium silicate: 7-10%. The raw materials of the glaze are mixed with water and auxiliary materials and then ball-milled. After the residue on a 325-mesh sieve reaches 0.8-1.0 wt%, the material is discharged and slurry is removed to remove iron, yielding a glaze slurry for use as the glaze. For example, the ball milling time is 6-7 hours. Auxiliary materials include, but are not limited to, sodium carboxymethyl cellulose, sodium carboxymethyl cellulose, and sodium tripolyphosphate. Water and auxiliary materials are not included in the raw material composition of the glaze. As an example, the sodium hydroxymethyl cellulose accounts for 0.1% to 0.5 wt% of the composition of the glaze raw materials, and the sodium tripolyphosphate accounts for 0.1% to 0.5 wt% of the composition of the glaze raw materials.

[0038] The preferred method for applying the glaze is by pouring. In some embodiments, the specific gravity of the glaze is 1.84–1.88 g / cm³. 3 The glaze application amount is 420-540 g / m². 2If the specific gravity and amount of glaze applied are too high, the expansion coefficient of the glaze layer will be too large, causing the brick to warp; if the specific gravity and amount of glaze applied are too low, the expansion coefficient of the glaze layer will be too small, causing the brick to arch.

[0039] Patterns are printed using inkjet printing on the surface of the tile after glazing. Digital inkjet printers can be used. Inkjet printing colors include, but are not limited to, blue, reddish-brown, orange, golden yellow, lemon yellow, black, and red. The texture and color effects of the inkjet-printed patterns vary according to design requirements.

[0040] After the inkjet-printed pattern is applied, the brick blanks are placed in a drying kiln for further drying. The drying temperature can be 100–150℃, and the drying time can be 5–7 minutes.

[0041] A fully polished glaze is applied to the surface of the brick blank after inkjet printing the pattern. The raw material composition of the fully polished glaze includes, by mass percentage: 40-50% albite, 15-20% clinker, 1-5% quartz, 1-4% calcined kaolin, 1-3% calcined alumina, 7-10% washed kaolin, 5-10% dolomite, 1-5% calcined talc, 1-3% calcite, 1-3% wollastonite, 1-4% zinc oxide, and 1-5% strontium carbonate. By introducing clinker into the fully polished glaze, the amount of flux with high loss on ignition is reduced, the melting temperature range of the glaze is increased, and the high-temperature viscosity of the glaze is reduced.

[0042] The raw material composition of the clinker includes, by mass percentage: 25-30% potassium feldspar, 7-12% sodium feldspar, 2-5% quartz, 1-4% aluminum hydroxide, 8-13% calcined kaolin, 7-15% (washed) kaolin, 10-15% dolomite, 4-7% calcite, 1-3% wollastonite, 2-3% zinc oxide, and 10-15% barium carbonate or barium sulfate.

[0043] The chemical composition of the clinker includes, by mass percentage: Loss on ignition: 0–0.11%; SiO2: 48.5–51.5%; Al2O3: 17.6–19.5%; Fe2O3: 0.1–0.3%; TiO2: 0.1–0.2%; CaO: 9.4–10.5%; MgO: 3.3–3.5%; K2O: 3.1–3.5%; Na2O: 1.5–2.2%; ZnO: 2.2–3.0%; BaO: 8.9–9.8%.

[0044] Clinker can be prepared as follows: According to the raw material composition of clinker, ingredients are prepared by adding water, sodium carboxymethyl cellulose, and sodium tripolyphosphate, followed by ball milling to prepare a glaze slurry. The ball milling speed and time can be varied as needed. For example, the ball milling speed can be 15–20 rpm, and the ball milling time can be 7–8 minutes. Alternatively, sodium carboxymethyl cellulose can account for 0.25%–0.35 wt% of the clinker raw material composition, and sodium tripolyphosphate can account for 0.4–0.5 wt%. Water, sodium carboxymethyl cellulose, and sodium tripolyphosphate are not included in the raw material composition of the clinker. The residue on a 325-mesh sieve of the glaze slurry can be 0.8–1.1 wt%. The glaze slurry is then spray-dried (powdered), pressed into brick blanks, and then dried, fired, and crushed to prepare clinker powder. As an example, the glaze slurry is spray-dried into powder, the powder is pressed into brick blanks, the brick blanks are dried, then fired in a roller kiln, and finally crushed into clinker powder. The firing temperature can be 1100~1150℃, and the firing time can be 38~45 minutes. This clinker has a simpler and more convenient preparation process and undergoes homogenization and pulverization, resulting in better stability compared to the frit. As an example, the particle size of the clinker can be 100μm~230μm.

[0045] In other words, the clinker described in this invention is prepared by using chemical materials, especially those with high thixotropy, to form a glaze slurry. This slurry is then homogenized through ball milling, sprayed to produce glaze powder, pressed into brick blanks, and finally fired at low temperatures and crushed to form clinker. Its greatest advantage is its high degree of homogenization and high stability. Even when materials with high thixotropy and high loss on ignition are used in fully polished glazed bricks, they will not cause defects on the brick surface.

[0046] This invention reduces the burn-off of the polished glaze, increases the silicon and aluminum content in the polished glaze, lowers the high-temperature viscosity of the polished glaze, and expands the firing range of the polished glaze by introducing the above-mentioned type of clinker into the full polished glaze formula, thereby solving the pinhole problem caused by low energy consumption and fast firing.

[0047] The chemical composition of the fully polished glaze includes, by mass percentage: loss on ignition: 5-7%; SiO2: 53.5-55%; Al2O3: 14.5-16.3%; Fe2O3: 0.1-0.2%; TiO2: 0.01-0.2%; CaO: 6-8.5%; MgO: 2.5-3.3%; K2O: 0.5-1.2%; Na2O: 3.5-4.5%; ZnO: 3.3-3.9%; BaO: 1.5-2.0%; SrO: 2.5-3.0%.

[0048] Prepare the glaze slurry for fully polished glaze. The raw materials for making the fully polished glaze are batched, and water, sodium carboxymethyl cellulose, and sodium tripolyphosphate are added and ball-milled to prepare the glaze slurry. The ball milling speed and time can be varied as needed. For example, the ball milling speed can be 15–20 rpm, and the ball milling time can be 10–11 minutes. Water, sodium carboxymethyl cellulose, and sodium tripolyphosphate are not included in the raw material composition of the fully polished glaze. Alternatively, sodium carboxymethyl cellulose can account for 0.1–0.15 wt% of the raw material composition of the fully polished glaze, and sodium tripolyphosphate can account for 0.35–0.42 wt%. The residue on a 325-mesh sieve of the glaze slurry can be 0.4–0.6 wt%.

[0049] The glazing method for the fully polished glaze is pouring glaze. In some embodiments, the specific gravity of the fully polished glaze is 1.84–1.88 g / cm³. 3 The glaze application amount is 420-540 g / m². 2 A low glaze application rate in fully polished glazes will result in noticeable water ripples and poor surface smoothness after polishing. Conversely, a high glaze application rate can easily lead to defects such as cracking or spalling.

[0050] It is fired in a kiln. The firing temperature is 1210-1230℃, and the firing cycle is 37-50 minutes.

[0051] Polishing. Polishing is performed in the order of rough polishing, medium polishing, and fine polishing. For example, rough polishing uses 8 sets of 180-grit resin sawtooth abrasive blocks and 8 sets of 240-grit resin sawtooth abrasive blocks in sequence, with a polishing pressure of 2.5 kg; medium polishing uses 8 sets of 320-grit and 8 sets of 400-grit elastic abrasive blocks in sequence, with a polishing pressure of 3 kg; fine polishing uses 4 sets of 600-grit, 4 sets of 800-grit, 4 sets of 1000-grit, and 4 sets of 2000-grit elastic abrasive blocks in sequence, with a polishing pressure of 3 kg.

[0052] In summary, in order to reduce the intake of carbonates in polished glaze and reduce the burn-off of the glaze, this invention prepares the chemical materials with high burn-off by making them into a mature material, and then introduces the mature material powder into the polished glaze formula to replace the chemical materials with high burn-off, and then prepares a fully polished glaze slurry, thus solving the problem of pinholes in the "volcano" shape.

[0053] 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.

[0054] Example 1

[0055] The preparation method of fully polished bricks includes the following steps:

[0056] 1. Press the raw material powder into brick blanks using a press.

[0057] 2. Dry the brick blanks using a drying kiln.

[0058] 3. Apply a surface glaze to the dried brick surface. The chemical composition of the surface glaze includes, by mass percentage: Loss on ignition: 2.14%, SiO2: 57.18%, Al2O3: 25.45%, Fe2O3: 0.16%, TiO2: 0.08%, CaO: 1.26%, MgO: 1.02%, K2O: 4.06%, Na2O: 2.95%, ZrO2: 5.62%. The raw material composition of the surface glaze includes, by mass percentage: Potassium feldspar: 35%, Nepheline: 17%, Quartz: 15%, Calcined alumina: 15%, Washed kaolin: 7%, Dolomite: 1%, Calcined talc: 3%, Zirconium silicate: 7%. The specific gravity of the surface glaze is 1.85 g / cm³. 3 Glazing amount is 440g / m 2 .

[0059] 4. Print patterns on the surface of the brick after glazing.

[0060] 5. The brick blanks with inkjet-printed patterns are then put back into the drying kiln for drying.

[0061] 6. Preparation of Clinker. The raw materials for clinker are prepared by batching according to their composition, adding water, sodium carboxymethyl cellulose, and sodium tripolyphosphate, and then ball-milling to prepare a glaze slurry. The raw material composition of the clinker includes, by mass percentage: 27% potassium feldspar, 9% sodium feldspar, 4.5% quartz, 2% aluminum hydroxide, 9% calcined kaolin, 13.5% washed kaolin, 13.5% dolomite, 4.5% calcite, 3% wollastonite, 3% zinc oxide, and 11% barium carbonate. Sodium carboxymethyl cellulose accounts for 0.25 wt% of the clinker raw material composition, and sodium tripolyphosphate accounts for 0.4 wt%. The glaze slurry has a residue of 0.9 wt% after passing through a 325-mesh sieve. The glaze slurry is spray-dried to prepare a powder. The powder is pressed into brick blanks, which are then dried and fired in a roller kiln, subsequently crushed into clinker powder. The firing temperature is 1150℃, and the firing time is 42 minutes.

[0062] 7. Apply a fully polished glaze to the dried brick surface. The raw material composition of the fully polished glaze includes, by mass percentage: 46% sodium feldspar, 16% clinker, 5% quartz, 2% calcined kaolin, 2% calcined alumina, 8% washed kaolin, 5% dolomite, 3% calcined talc, 3% calcite, 3% wollastonite, 3% zinc oxide, and 4% strontium carbonate. The chemical composition of the fully polished glaze includes, by mass percentage: loss on ignition: 6.41%; SiO2: 54.37%; Al2O3: 16.18%; Fe2O3: 0.19%; TiO2: 0.07%; CaO: 6.4%; MgO: 2.72%; K2O: 0.83%; Na2O: 4.48%; ZnO: 3.9%; BaO: 1.51%; SrO: 2.71%. The specific gravity of the fully polished glaze is 1.85 g / cm³. 3 Glazing amount is 440g / m 2 .

[0063] 8. The glazed brick blanks are then fired in a kiln. The maximum firing temperature is 1225℃, and the firing cycle is 45 minutes.

[0064] 9. Polishing. Polishing is performed in the following order: rough polishing, medium polishing, and fine polishing. For rough polishing, use 8 sets of 180-grit resin sawtooth abrasive blocks and 8 sets of 240-grit resin sawtooth abrasive blocks in sequence, with a polishing pressure of 2.5 kg. For medium polishing, use 8 sets of 320-grit and 8 sets of 400-grit elastic abrasive blocks in sequence, with a polishing pressure of 3 kg. For fine polishing, use 4 sets of 600-grit, 4 sets of 800-grit, 4 sets of 1000-grit, and 4 sets of 2000-grit elastic abrasive blocks in sequence, with a polishing pressure of 3 kg.

[0065] 10. Edge grinding.

[0066] like Figure 1 As shown, after using the clinker formula of Example 1, no "volcano-like" pinholes appeared on the brick surface. This is because: the fully polished glaze uses a custom-formulated clinker, which significantly reduces its high-temperature viscosity, while also reducing the burn-off of the glaze, widening the melting temperature range of the glaze, improving the stability of the clinker, and promoting gas release.

[0067] Comparative Example 1

[0068] The process is essentially the same as in Example 1, except that the raw material composition of the fully polished glaze includes, by mass percentage: 42% albite, 5% clinker, 5% quartz, 2% calcined alumina, 3% calcined kaolin, 8% washed kaolin, 14% dolomite, 6% calcined talc, 3% calcite, 3% wollastonite, 4% zinc oxide, and 5% strontium carbonate. The chemical composition of the fully polished glaze includes, by mass percentage: loss on ignition: 10.61%; SiO2: 49.13%; Al2O3: 14.21%; Fe2O3: 0.19%; TiO2: 0.05%; CaO: 8.08%; MgO: 4.96%; K2O: 0.51%; Na2O: 3.94%; ZnO: 4.13%; BaO: 0.48%; SrO: 3.48%. The specific gravity of the fully polished glaze is 1.83 g / cm³. 3 The glaze application amount is 420g / m². 2 .

[0069] like Figure 2 As shown, the brick surface in this comparative example exhibits pinholes shaped like a volcano. These pinholes are located between the surface glaze layer and the fully polished glaze layer, with a diameter of more than 1.2 mm, and appear as single white dots after polishing.

[0070] Comparative Example 2

[0071] The process is essentially the same as in Example 1, except that the chemical composition of the glaze includes, by mass percentage: loss on ignition: 2.27%, SiO2: 52.27%, Al2O3: 29.85%, Fe2O3: 0.16%, TiO2: 0.04%, CaO: 1.35%, MgO: 0.54%, K2O: 2.93%, Na2O: 5.08%, ZrO2: 5.48%. The raw material composition of the glaze includes, by mass percentage: potassium feldspar: 20%, sodium feldspar: 24%, nepheline: 15%, quartz: 11%, calcined alumina: 14%, washed kaolin: 7%, dolomite: 1%, zirconium silicate: 8%. The specific gravity of the glaze is 1.83 g / cm³. 3 Glazing amount is 440g / m 2 .

[0072] The brick surface in this comparison still has pinholes shaped like a crater.

[0073] In addition, the inventors also tried increasing the content of calcined alumina and quartz in the glaze, or adding dolomite and calcined talc to the glaze, but none of these methods could solve the pinhole problem.

[0074] Comparative Example 3

[0075] The process is essentially the same as in Example 1, except that the raw material composition of the fully polished glaze includes, by mass percentage: 48% albite, 6% quartz, 3% calcined kaolin, 2% calcined alumina, 8% washed kaolin, 17% dolomite, 3% calcined talc, 3% calcite, 3% wollastonite, 3% zinc oxide, and 4% strontium carbonate. The chemical composition of the fully polished glaze includes, by mass percentage: loss on ignition: 11.73%; SiO2: 50.2%; Al2O3: 14.22%; Fe2O3: 0.17%; TiO2: 0.09%; CaO: 8.57%; MgO: 4.53%; K2O: 0.35%; Na2O: 4.39%; ZnO: 2.97%; SrO: 2.78%. The specific gravity of the fully polished glaze is 1.83 g / cm³. 3 The glaze application amount is 430g / m² 2 .

[0076] like Figure 3 The comparative example used fully polished glazed tiles made entirely from raw materials. After firing and polishing, the tile surface exhibited deep pores resembling "volcano craters," with a pore diameter of approximately 0.6-0.8 mm. Furthermore, when the above steps were repeated to prepare ten fully polished glazed ceramic tile samples, it was found that approximately 10% of the ceramic tile samples had the aforementioned pinholes.

[0077] like Figure 4 As shown, magnification of the pinhole reveals that it is located between the surface glaze layer and the fully polished glaze layer.

[0078] Comparative Example 4

[0079] The process is essentially the same as in Example 1, except that the raw material composition of the fully polished glaze includes, by mass percentage: 42% sodium feldspar, 19% clinker, 5% quartz, 2% calcined kaolin, 2% calcined alumina, 8% washed kaolin, 6% dolomite, 3% calcined talc, 3% calcite, 3% wollastonite, 3% zinc oxide, and 4% strontium carbonate. The clinker composition includes, by mass percentage: 10% potassium feldspar, 50% sodium feldspar, 2% calcined kaolin, 6% washed kaolin, 10% dolomite, 5% calcite, 3% wollastonite, 4% zinc oxide, 4% calcined talc, and 6% barium carbonate. The specific gravity of the fully polished glaze is 1.84 g / cm³. 3 Glazing amount is 440g / m 2 .

[0080] like Figure 5 As shown, the brick surface in this comparative example exhibits a single pinhole with a large diameter after polishing. This is because although the loss on ignition is reduced in the fully polished glaze of this comparative example, the viscosity at high temperatures remains high, which easily leads to localized single pinholes.

[0081] Comparative Example 5

[0082] It is basically the same as Example 1, except that the specific gravity of the fully polished glaze is 1.83 g / cm³. 3 Glazing amount is 340g / m 2 .

[0083] like Figure 6 As shown, the brick surface in this comparative example still exhibits obvious water ripples even after polishing.

[0084] Comparative Example 6

[0085] It is basically the same as Example 1, except that the specific gravity of the fully polished glaze is 1.87 g / cm³. 3 The glaze application amount is 940g / m 2 .

[0086] like Figure 7 As shown, the bricks in this comparison are prone to cracking. This is because the glaze application in fully polished glazed bricks is too heavy, resulting in excessive moisture in the brick body and uneven heating, which easily leads to cracking.

Claims

1. A full polishing enamel, characterized in that, The raw material composition of the fully polished glaze includes, by mass percentage: 40%–50% sodium feldspar, 15%–20% clinker, 1%–5% quartz, 1%–4% calcined kaolin, 1%–3% calcined alumina, 7%–10% washed kaolin, 5%–10% dolomite, 1%–5% calcined talc, 1%–3% calcite, 1%–3% wollastonite, 1%–4% zinc oxide, and 1%–5% strontium carbonate; the raw material composition of the clinker includes, by mass percentage: 25%–30% potassium feldspar, 7%–12% sodium feldspar, and quartz... The raw materials are: 2%–5% iodine, 1%–4% aluminum hydroxide, 8%–13% calcined kaolin, 7%–15% washed kaolin, 10%–15% dolomite, 4%–7% calcite, 1%–3% wollastonite, 2%–3% zinc oxide, and 10%–15% barium carbonate or barium sulfate. The clinker is prepared by: mixing the raw materials according to the clinker composition, adding water, sodium hydroxymethyl cellulose, and sodium tripolyphosphate, and ball milling to prepare a glaze slurry; spray drying the glaze slurry into powder, pressing it into a blank, and then drying, firing, and crushing it to obtain the clinker.

2. The fully polished glazed porcelain according to claim 1, characterized in that, The sodium carboxymethyl cellulose accounts for 0.25 wt% to 0.35 wt% of the clinker raw material composition, and the sodium tripolyphosphate accounts for 0.4 wt% to 0.5 wt% of the clinker raw material composition.

3. The fully polished glazed porcelain according to claim 1, characterized in that, The chemical composition of the fully polished glaze includes, by mass percentage: loss on ignition: 5%–7%; SiO2: 53.5%–55%; Al2O3: 14.5%–16.3%; Fe2O3: 0.1%–0.2%; TiO2: 0.01%–0.2%; CaO: 6%–8.5%; MgO: 2.5%–3.3%; K2O: 0.5%–1.2%; Na2O: 3.5%–4.5%; ZnO: 3.3%–3.9%; BaO: 1.5%–2.0%; SrO: 2.5%–3.0%.

4. A method for preparing fully polished glazed ceramic tiles, characterized in that, Includes the following steps: Brick blanks are obtained by pressing the raw material powder into shape. Dry the brick blanks; Apply a surface glaze to the dried brick blank; Inkjet printing of patterns on the surface of the brick blank after the glaze has been applied; Apply a fully polished glaze according to any one of claims 1 to 3 to the surface of the brick blank after inkjet printing the pattern; Fully polished glazed ceramic tiles are obtained by firing in a kiln and polishing.

5. The preparation method according to claim 4, characterized in that, The full polishing enamel is applied by spraying, and has a specific gravity of 1.84-1.88 g / cm 3 , and an enamel application amount of 420-540 g / m 2 .

6. The preparation method according to claim 4, characterized in that, The firing temperature is 1210–1230℃, and the firing cycle is 37–50 minutes.

7. The preparation method according to claim 4, characterized in that, The chemical composition of the surface glaze includes, by mass percentage: SiO2: 57.0%–60.3%, Al2O3: 25.0%–30%, Fe2O3: 0.1%–0.2%, TiO2: 0.04%–0.1%, CaO: 0.5%–1.5%, MgO: 0.5%–1.5%, K2O: 3.5%–4.6%, Na2O: 2.1%–3.5%, ZrO2: 4.1%–6.0%.

8. The preparation method according to claim 4, characterized in that, The face glaze is applied by spraying, and has a specific gravity of 1.84-1.88 g / cm 3 and a glaze amount of 420-540 g / m 2 .

9. Fully polished glazed ceramic tiles, characterized in that, The fully polished glazed ceramic tile is obtained by the preparation method according to any one of claims 4 to 8.

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