Multi-layer glass ceramic shaping device, multi-layer lithium disilicate glass ceramic and preparation method of multi-layer lithium disilicate glass ceramic

Abstract

The invention relates to a multi-layer glass ceramic shaping device, multi-layer lithium disilicate glass ceramic and a preparation method thereof. The multi-layer glass ceramic shaping device comprises a melting and cooling unit, a material guiding unit and a shaping unit which are sequentially connected from top to bottom, the melting cooling unit comprises m melting cooling assemblies which are arranged in parallel; the material guide unit comprises n material guide parts; a heat preservation component is further arranged on the outer side of each material guide component; the shaping unit comprises a first shaping assembly and a second shaping assembly arranged on the lower portion of the first shaping assembly, the first shaping assembly comprises p first shaping clamping plates, and m = n = p > = 2; a first discharge port of the melting and cooling assembly is connected with an inlet of the material guide part, and an outlet of the material guide part is connected with the first shaping clamping plate; continuous preparation of the multi-layer lithium disilicate glass ceramics is achieved, and the current requirement for gradient color or multi-layer color glass ceramics is met.

Description

Technical Field

[0001] This invention relates to the field of multilayer microcrystalline glass and its preparation technology, and in particular to a multilayer microcrystalline glass shaping device, multilayer lithium disilicate microcrystalline glass and its preparation method. Background Technology

[0002] Microcrystalline glass is a novel material that combines the properties of both glass and ceramics by adding nucleating agents to traditional glass formulations, followed by molding and heat treatment to achieve controlled crystallization. Its core advantage lies in the ability to precisely control the ratio of the glassy phase to the crystalline phase by adjusting the nucleating agent content, thus achieving directional adjustment of material properties between the glassy and ceramic states. For example, lithium disilicate microcrystalline glass is a glass-ceramic composite material prepared with Li₂Si₂O₅ as the main crystalline phase and SiO₂-Li₂O as the glass matrix. It is made by adding fluxes such as K₂O, P₂O₅, Al₂O₃, ZrO₂, B₂O₃, ZnO, MgO, or CaO, nucleating agents, and reinforcing agents, as well as colorants such as Fe₂O₃, Co₂O₃, CeO₂, and Er₂O₃.

[0003] Lithium disilicate glass-ceramics have become an important material in the field of dental restorations due to their excellent machinability, optical transmittance, mechanical strength, and biocompatibility. However, current technologies mainly focus on the preparation of single homogeneous ceramic blocks, which is insufficient to meet the clinical demand for simulating color gradients and transparency gradations in restorations. Specifically, single-layer lithium disilicate glass-ceramics have shortcomings in color control. Severe decomposition and volatilization of pigments during the high-temperature melting stage leads to poor color stability and an inability to achieve color gradations. Single-layer lithium disilicate glass-ceramics also have low light transmittance, making it difficult to fully simulate the translucent texture of natural teeth, especially in anterior restorations, where aesthetic results are limited. Furthermore, the surface properties of single-layer lithium disilicate glass-ceramics are not ideal, easily attracting bacteria and food debris, increasing the risk of secondary caries.

[0004] For example, CN103360041B discloses a carbon / lithium disilicate composite ceramic material and its preparation method. The composition system and performance design of this composite ceramic material do not consider biocompatibility requirements, do not involve any biomedical or dental applications, and are not suitable for the field of oral restoration. CN101139170B discloses a lithium disilicate microcrystalline glass composite material with ZrO2 as the reinforcing phase and its preparation method. The addition of high-refractive-index ZrO2 results in a significant difference in refractive index between the ZrO2 and the glass matrix, causing strong light scattering, leading to opacity and poor process controllability.

[0005] Since the aforementioned technical solutions all focus on the preparation process of single-component systems and do not involve the molding methods for gradient transparency or gradient colors, nor do they reveal their construction mechanisms, there is an urgent need to develop a preparation equipment and technology for multilayer lithium disilicate glass-ceramics to overcome the technical bottleneck of existing technologies being unable to prepare gradient / multilayer colored ceramic blocks. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a multilayer microcrystalline glass shaping device, multilayer lithium disilicate microcrystalline glass, and a method for preparing the same, enabling continuous preparation of multilayer colored or gradient-colored microcrystalline glass, thus overcoming the shortcomings of existing technologies that focus on preparing ceramic blocks with a single color or single formula.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a multilayer microcrystalline glass shaping device, the multilayer microcrystalline glass shaping device comprising a melting and cooling unit, a material guiding unit and a shaping unit connected sequentially from top to bottom;

[0009] The melting and cooling unit includes m melting and cooling components arranged in parallel; the material guiding unit includes n material guiding parts; each material guiding part is also provided with a heat insulation part on its outer side; the shaping unit includes a first shaping component and a second shaping component arranged below the first shaping component, the first shaping component includes p first shaping clamps, and m=n=p≥2, for example, it can be 2, 3, 4, 5 or 6, etc.

[0010] The first outlet of the melt cooling assembly is connected to the inlet of the material guiding component, and the outlet of the material guiding component is connected to the first shaping clamp.

[0011] The multilayer microcrystalline glass shaping device of the present invention, by designing the material guiding component and using the first shaping component and the second shaping component in combination, allows glass liquid of different compositions to be pre-shaped first, and then the pre-shaped glass of different compositions is subjected to secondary shaping, and extruded with each other to form a whole multilayer microcrystalline glass, thus meeting the market demand for gradient color or multi-color microcrystalline glass.

[0012] Preferably, m, n, and p satisfy: 2≤m=n=p≤6.

[0013] Preferably, the melt-cooling assembly includes a melting assembly and a cooling assembly disposed below the melting assembly.

[0014] Preferably, the melting assembly includes a heat-insulating shell, a first heating element, and a melting container; the melting container is disposed inside the heat-insulating shell; and the first heating element is disposed in the cavity between the heat-insulating shell and the melting container.

[0015] Preferably, the bottom of the melting container is provided with a second discharge port.

[0016] Preferably, the cooling assembly includes a cooling container and a second heating element disposed on the outer periphery of the cooling container.

[0017] Preferably, the first discharge port is located at the bottom of the cooling container.

[0018] Preferably, the first shaping assembly further includes a first retraction component disposed on the outside of each of the first shaping clamps.

[0019] Preferably, the second shaping component includes a second shaping clamp and a second shrinking member disposed on the outside of the second shaping clamp.

[0020] Preferably, the materials of the first shaping clamp and the second shaping clamp include any one or a combination of at least two of stainless steel, cast iron, platinum or graphite.

[0021] Preferably, the edge shape of the first shaping clamp includes any one of straight, serrated, wavy, concave arc, or convex arc.

[0022] Preferably, the second clamp has a rectangular shape.

[0023] Secondly, the present invention provides a method for preparing multilayer lithium disilicate glass-ceramics, wherein the preparation method employs the multilayer glass-ceramics shaping device described in the first aspect for shaping.

[0024] The preparation method of the present invention uses the multilayer microcrystalline glass shaping device described in the first aspect. The device simultaneously realizes pre-shaping and secondary shaping, realizing continuous production of multilayer lithium disilicate microcrystalline glass. While improving the color and transparency effect, it also improves production efficiency and avoids the problem of poor secondary shaping effect caused by the long time interval in the traditional single-set shaping device and manual stacking secondary shaping process.

[0025] Preferably, the preparation method includes the following steps: melting and cooling glass raw materials of different compositions respectively, and then subjecting the resulting mud-like glass liquid to a first shaping to obtain pre-shaped glass of different compositions. After stacking all the pre-shaped glass, a second shaping is performed simultaneously to obtain shaped glass, and then crystallization treatment is performed to obtain multilayer lithium disilicate microcrystalline glass.

[0026] Preferably, based on mass percentage, each of the glass raw materials comprises 30-50 wt% SiO2, 15-30 wt% Li2O, 3-10 wt% K2O, 0-10 wt% P2O5, 5-15 wt% Ti2O, 0-5 wt% Al2O3, 5-10 wt% ZrO2, 0-5 wt% CeO2, 0-10 wt% B2O3, 0-10 wt% ZnO, and 0-10 wt% colorant.

[0027] The composition includes: SiO2 30-50 wt%, for example, 30 wt%, 35 wt%, 40 wt%, 45 wt%, or 50 wt%; Li2O 15-30 wt%, for example, 15 wt%, 18 wt%, 20 wt%, 22 wt%, 25 wt%, 28 wt%, or 30 wt%; K2O 3-10 wt%, for example, 3 wt%, 5 wt%, 7 wt%, 9 wt%, or 10 wt%; P2O5 0-10 wt%, for example, 0 wt%, 2 wt%, 5 wt%, 8 wt%, or 10 wt%; Ti2O 5-15 wt%, for example, 5 wt%, 8 wt%, 10 wt%, 12 wt%, or 15 wt%; Al2O3 0-5 wt%, for example, 0 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, or 5 wt%; ZrO2 5~10wt%, for example, it can be 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, or 10wt%; CeO2 0~5wt%, for example, it can be 0wt%, 1wt%, 2wt%, 3wt%, 4wt%, or 5wt%; B2O3 0~10wt%, for example, it can be 0wt%, 2wt%, 4wt%, 6wt%, 8wt%, or 10wt%; ZnO 0~10wt%, for example, it can be 0wt%, 2wt%, 4wt%, 6wt%, 8wt%, or 10wt%; colorant 0~10wt%, for example, it can be 0wt%, 2wt%, 4wt%, 6wt%, 8wt%, or 10wt%.

[0028] Preferably, the colorant includes V2O5, Er2O3, and Pr6O. 11 Any one or at least two of Fe2O3 or NiO, wherein typical but non-limiting combinations include combinations of V2O5 and Er2O3, combinations of V2O5 and NiO, or combinations of V2O5, Er2O3 and Pr6O. 11 Combinations, etc.

[0029] Preferably, based on the glass raw material, the colorant comprises 0-2 wt% V₂O₅, 0-5 wt% Er₂O₃, and 0 wt% Pr₆O₅. 110~2wt%, Fe2O3 0~1.3wt%, and NiO 0~1wt%.

[0030] Among them, V2O5 is 0~2wt%, for example, it can be 0wt%, 0.5wt%, 1wt%, 1.5wt%, or 2wt%; Er2O3 is 0~5wt%, for example, it can be 0wt%, 1wt%, 2wt%, 3wt%, 4wt%, or 5wt%; Pr6O 11 0~2wt%, for example, it can be 0wt%, 0.4wt%, 0.8wt%, 1.2wt%, 1.8wt%, or 2wt%, etc.; Fe2O3 0~1.3wt%, for example, it can be 0wt%, 0.2wt%, 0.4wt%, 0.6wt%, 0.8wt%, 1wt%, 1.1wt%, 1.2wt%, or 1.3wt%, etc.; NiO 0~1wt%, for example, it can be 0wt%, 0.2wt%, 0.4wt%, 0.6wt%, 0.8wt%, or 1wt%, etc.

[0031] Preferably, the melting temperature is 1350~1600℃, for example, it can be 1350℃, 1400℃, 1450℃, 1500℃, 1550℃ or 1600℃.

[0032] Preferably, the melting and holding time is 0.5 to 4 hours, for example, it can be 0.5 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours.

[0033] Preferably, the molten atmosphere includes an air atmosphere and / or an inert atmosphere.

[0034] Preferably, the cooling temperature is 1050~1350℃, for example, it can be 1050℃, 1150℃, 1250℃ or 1350℃.

[0035] Preferably, the cooling and heat preservation time is 0.5 to 4 hours, for example, it can be 0.5 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours.

[0036] The pressure applied during the first shaping process is 5~50N, for example, it can be 5N, 10N, 15N, 20N, 25N, 30N, 35N, 40N, 45N or 50N, etc.

[0037] Preferably, the pressure applied during the second shaping process is 10~100N, for example, it can be 10N, 20N, 30N, 40N, 50N, 60N, 70N, 80N, 90N or 100N, etc.

[0038] Preferably, the preparation method further includes, after the second shaping, cutting the shaped product to the target size to obtain the target shaped glass.

[0039] Preferably, the preparation method further includes sequentially heat preservation and cooling after shearing.

[0040] Preferably, the insulation temperature after shearing is 300~500℃, for example, it can be 300℃, 350℃, 400℃, 450℃ or 500℃, etc.

[0041] Preferably, the heat preservation time after shearing is 0.5 to 4 hours, for example, it can be 0.5 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours.

[0042] Preferably, the cooling method after shearing includes furnace cooling.

[0043] Preferably, the crystallization process includes sequential heating and heat preservation.

[0044] Preferably, the final temperature of the heating is 600~900℃, for example, it can be 600℃, 650℃, 700℃, 750℃, 800℃, 850℃ or 900℃, etc.

[0045] Preferably, the heating rate is 5~15℃ / min, for example, it can be 5℃ / min, 8℃ / min, 10℃ / min, 12℃ / min or 15℃ / min, etc.

[0046] Preferably, the heat preservation time is 0.5 to 60 minutes, for example, it can be 0.5 minutes, 5 minutes, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.

[0047] Thirdly, the present invention provides a multilayer lithium disilicate microcrystalline glass, which is prepared by the preparation method described in the second aspect.

[0048] The multilayer lithium disilicate microcrystalline glass of this invention has advantages such as the ability to achieve natural transitions in both color and strength.

[0049] Compared with the prior art, the present invention has at least the following beneficial effects:

[0050] (1) The multilayer microcrystalline glass shaping device provided by the present invention, by designing the material guiding component and combining the first shaping component and the second shaping component, allows glass liquid of different compositions to be pre-shaped first, and then the pre-shaped glass of different compositions is subjected to secondary shaping, and extruded to form a whole multilayer microcrystalline glass, which meets the market demand for gradient color or multilayer color microcrystalline glass.

[0051] (2) The preparation method of multilayer lithium disilicate microcrystalline glass provided by the present invention is carried out using the above-mentioned multilayer microcrystalline glass shaping device. The pre-shaping and secondary shaping are realized simultaneously in one device. Then, the glass raw materials are adjusted according to the requirements of different transparency, different colors, etc., to realize the continuous production of multilayer lithium disilicate microcrystalline glass.

[0052] (3) The multilayer lithium disilicate microcrystalline glass provided by the present invention has the advantage of more natural color transition compared with traditional single-color or single-component lithium disilicate microcrystalline glass. Teeth made using it are more in line with the natural tooth color system and are more beautiful. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the structure and connection relationship of the multilayer microcrystalline glass shaping device provided in Embodiment 1 of the present invention.

[0054] Figure 2 This is a schematic diagram of the edge shape of the first shaping clamp in the multilayer microcrystalline glass shaping device provided in Embodiment 1 of the present invention, where a is straight, b is serrated, c is wavy, d is concave arc, and e is convex arc.

[0055] In the figure: 1. Melting and cooling assembly; 2. Melting container; 3. Insulating shell; 4. First heating component; 5. Cooling container; 6. Second heating component; 7. Material guiding component; 8. Insulation component; 9. First shaping clamp; 10. First shrinking component; 11. Second shaping clamp; 12. Second shrinking component. Detailed Implementation

[0056] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0057] In the following embodiments or comparative examples, both the first shrinking component and the second shrinking component are electrically driven to shrink.

[0058] In the following examples or comparative examples, the glass raw materials of each formulation are melted and cooled sequentially in the corresponding melting and cooling assembly according to the formulation number.

[0059] The parameters of the second shaping and the crystallization treatment in the preparation methods described in Examples 1 to 3 are shown in Table 1;

[0060] Table 1

[0061]

[0062] I. Implementation Examples

[0063] Example 1

[0064] This embodiment provides a multilayer microcrystalline glass shaping device, such as... Figure 1 As shown, the multilayer microcrystalline glass shaping device includes a melting and cooling unit, a material guiding unit, and a shaping unit connected sequentially from top to bottom;

[0065] The melting and cooling unit includes four melting and cooling components 1 arranged in parallel; the material guiding unit includes four material guiding parts 7; each material guiding part 7 is further provided with a heat insulation part 8 on its outer side; the shaping unit includes a first shaping component and a second shaping component disposed below the first shaping component, the first shaping component including four first shaping clamps 9; the first discharge port of the melting and cooling component 1 is connected to the inlet of the material guiding part 7, and the outlet of the material guiding part 7 is connected to the first shaping clamp 9;

[0066] The melting and cooling assembly 1 includes a melting assembly and a cooling assembly disposed at the lower part of the melting assembly; the melting assembly includes a heat-insulating shell 3, a first heating component 4, and a melting container 2; the melting container 2 is disposed inside the heat-insulating shell 3; the first heating component 4 is disposed in the cavity between the heat-insulating shell 3 and the melting container 2; a second discharge port is provided at the bottom of the melting container 2; the cooling assembly includes a cooling container 5 and a second heating component 6 disposed on the outer periphery of the cooling container 5; the first discharge port is disposed at the bottom of the cooling container 5; the first shaping assembly also includes a first shrinking component 10 disposed on the outer side of each of the first shaping clamps 9; the second shaping assembly includes a second shaping clamp 11 and a second shrinking component 12 disposed on the outer side of the second shaping clamp 11; the first shaping clamp 9 and the second shaping clamp 11 are both made of stainless steel, and the edge shape of the first shaping clamp 9 includes any one of the following: straight a, serrated b, wavy c, concave arc d, or convex arc e (e.g., ...). Figure 2 (As shown); the second clamp is rectangular in shape.

[0067] In the following preparation method, the edge shape of the first shaping clamp 9 is straight a.

[0068] This embodiment also provides a method for preparing multilayer lithium disilicate microcrystalline glass. The preparation method uses the above-mentioned multilayer glass shaping device for shaping. The preparation method includes the following steps: mixing four different glass raw materials in a mixer for 1.5 hours, then melting and cooling them separately. The resulting mud-like glass liquid is subjected to a first shaping to obtain pre-shaped glass with different compositions. All the pre-shaped glass is then stacked and subjected to a second shaping simultaneously. After shearing, it is kept at 400°C for 3 hours and then cooled in a furnace to obtain shaped glass. Finally, it is subjected to crystallization treatment to obtain multilayer lithium disilicate microcrystalline glass.

[0069] The glass raw material formulation and the parameters for melting, cooling and first shaping of each formulation in this embodiment are shown in Table 2.

[0070] Table 2

[0071]

[0072] In this embodiment, the second shaping and the crystallization treatment adopt the parameters corresponding to Example 1 in Table 1.

[0073] This embodiment also provides a multilayer lithium disilicate microcrystalline glass, which is prepared using the preparation method described in this embodiment and has a natural color transition.

[0074] Example 2

[0075] This embodiment provides a multilayer microcrystalline glass shaping device, which includes a melting and cooling unit, a material guiding unit, and a shaping unit connected sequentially from top to bottom.

[0076] The melting and cooling unit includes three melting and cooling components arranged in parallel; the material guiding unit includes three material guiding parts; each material guiding part is further provided with a heat insulation part on its outer side; the shaping unit includes a first shaping component and a second shaping component disposed below the first shaping component, the first shaping component including three first shaping clamps; the first outlet of the melting and cooling component is connected to the inlet of the material guiding part, and the outlet of the material guiding part is connected to the first shaping clamp;

[0077] The melting and cooling assembly includes a melting assembly and a cooling assembly disposed below the melting assembly; the melting assembly includes a heat-insulating shell, a first heating element, and a melting container; the melting container is disposed inside the heat-insulating shell; the first heating element is disposed in the cavity between the heat-insulating shell and the melting container; a second discharge port is provided at the bottom of the melting container; the cooling assembly includes a cooling container and a second heating element disposed on the outer periphery of the cooling container; the first discharge port is disposed at the bottom of the cooling container; the first shaping assembly further includes a first shrinking element disposed on the outer side of each of the first shaping clamps; the second shaping assembly includes a second shaping clamp and a second shrinking element disposed on the outer side of the second shaping clamp; both the first shaping clamp and the second shaping clamp are made of stainless steel, and the edge shape of the first shaping clamp includes any one of straight, serrated, wavy, concave arc, or convex arc; the shape of the second clamp is rectangular.

[0078] In the following preparation method, the edge shape of the first shaping clamp is selected to be serrated.

[0079] This embodiment also provides a method for preparing multilayer lithium disilicate microcrystalline glass. The preparation method uses the above-mentioned multilayer glass shaping device for shaping. The preparation method includes the following steps: mixing three glass raw materials with different compositions in a mixer for 1 hour, then melting and cooling them separately, and the resulting mud-like glass liquid undergoes a first shaping process to obtain pre-shaped glass with different compositions. Then, all the pre-shaped glass is stacked and simultaneously subjected to a second shaping process. After shearing, it is kept at 300°C for 4 hours and then cooled in a furnace to obtain shaped glass. Finally, it undergoes crystallization treatment to obtain multilayer lithium disilicate microcrystalline glass.

[0080] The glass raw material formulation and the melting, cooling and first shaping parameters of each formulation in this embodiment are shown in Table 3.

[0081] Table 3

[0082]

[0083] In this embodiment, the second shaping and the crystallization treatment adopt the parameters corresponding to Example 2 in Table 1.

[0084] This embodiment also provides a multilayer lithium disilicate microcrystalline glass, which is prepared using the preparation method described in this embodiment and has a natural gradient effect.

[0085] Example 3

[0086] This embodiment provides a multilayer microcrystalline glass shaping device, which includes a melting and cooling unit, a material guiding unit, and a shaping unit connected sequentially from top to bottom.

[0087] The melting and cooling unit includes five melting and cooling components arranged in parallel; the material guiding unit includes five material guiding parts; each material guiding part is further provided with a heat insulation part on its outer side; the shaping unit includes a first shaping component and a second shaping component disposed below the first shaping component, the first shaping component including five first shaping clamps; the first outlet of the melting and cooling component is connected to the inlet of the material guiding part, and the outlet of the material guiding part is connected to the first shaping clamp;

[0088] The melting and cooling assembly includes a melting assembly and a cooling assembly disposed below the melting assembly; the melting container is disposed inside the heat-insulating shell; the first heating component is disposed in the cavity between the heat-insulating shell and the melting container; the melting assembly includes the heat-insulating shell, the first heating component, and the melting container; a second discharge port is provided at the bottom of the melting container; the cooling assembly includes a cooling container and a second heating component disposed on the outer periphery of the cooling container; the first discharge port is disposed at the bottom of the cooling container; the first shaping assembly further includes a first shrinking component disposed on the outer side of each of the first shaping clamps; the second shaping assembly includes a second shaping clamp and a second shrinking component disposed on the outer side of the second shaping clamp; the first shaping clamp and the second shaping clamp are both made of stainless steel, and the edge shape of the first shaping clamp includes any one of straight, serrated, wavy, concave arc, or convex arc; the shape of the second clamp is rectangular.

[0089] In the following preparation method, the edge shape of the first shaping clamp is selected to be wavy.

[0090] This embodiment also provides a method for preparing multilayer lithium disilicate microcrystalline glass. The preparation method uses the above-mentioned multilayer glass shaping device for shaping. The preparation method includes the following steps: mixing five different glass raw materials in a mixer for 2 hours, then melting and cooling them separately. The resulting mud-like glass liquid is subjected to a first shaping to obtain pre-shaped glass with different compositions. All the pre-shaped glass is then stacked and subjected to a second shaping simultaneously. After shearing, it is kept at 500°C for 2 hours and then cooled in a furnace to obtain shaped glass. Finally, it is subjected to crystallization treatment to obtain multilayer lithium disilicate microcrystalline glass.

[0091] The glass raw material formulation and the parameters for melting, cooling and first shaping of each formulation in this embodiment are shown in Table 4.

[0092] Table 4

[0093]

[0094] In this embodiment, the second shaping and the crystallization treatment adopt the parameters corresponding to Example 3 in Table 1.

[0095] This embodiment also provides a multilayer lithium disilicate microcrystalline glass, which is prepared using the preparation method described in this embodiment. It exhibits a gradient color with a natural transition.

[0096] II. Comparative Example

[0097] Comparative Example 1

[0098] This comparative example provides a multilayer microcrystalline glass shaping device. The shaping device is the same as that in Embodiment 1 except that it does not have the first shaping component, that is, it does not have the first shaping clamp and the first shaping shrinkage component.

[0099] This comparative example also provides a method for preparing multilayer lithium disilicate glass-ceramics. Except for using the multilayer glass-ceramic shaping device described in this comparative example, the preparation method is the same as in Example 1.

[0100] This comparative example also provides a multilayer lithium disilicate microcrystalline glass, which is identical to Example 1 except that it is prepared by the preparation method described in this comparative example.

[0101] Since the multilayer microcrystalline glass shaping device described in this comparative example does not have a first shaping component, the shaping process only includes the second shaping, resulting in the glass being round when it reaches the position of the second shaping component. The final glass block formed has a thickness of more than 6mm per layer, making it impossible to prepare a glass-ceramic block with a natural transition.

[0102] Comparative Example 2

[0103] This comparative example provides a multilayer microcrystalline glass shaping device, which is the same as that in Example 1 except that the heat insulation component is not provided on the outside of each of the material guiding components.

[0104] This comparative example also provides a method for preparing multilayer lithium disilicate microcrystalline glass. Except for the use of the multilayer microcrystalline glass shaping device described in this comparative example for shaping, the preparation method is the same as that in Example 1.

[0105] Since no heat preservation component was provided in this embodiment, the molten glass cooled into a block in the feed tank and did not flow, making it impossible to prepare multilayer lithium disilicate microcrystalline glass.

[0106] Comparative Example 3

[0107] This comparative example provides a multilayer microcrystalline glass shaping device, which does not include a material guiding unit as in Comparative Example 1. Instead, the outlet of the cooling component is directly connected to the second shaping clamp. All other aspects are the same as in Example 1.

[0108] This comparative example also provides a method for preparing multilayer lithium disilicate glass-ceramics. Except for using the multilayer glass-ceramic shaping device described in this comparative example, the preparation method is the same as in Example 1.

[0109] Because the multilayer microcrystalline glass shaping device described in this comparative example does not have a first shaping component and a material guiding unit, the molten glass cannot reach the second shaping component from the outlet of the cooling pot, which in turn causes the various glass materials to be unable to bond together, making it impossible to prepare multilayer lithium disilicate microcrystalline glass.

[0110] Comparative Example 4

[0111] This comparative example provides a method for preparing multilayer lithium disilicate microcrystalline glass. The preparation method does not use the multilayer single crystal glass preparation device described in Example 1. Instead, it uses a traditional single-set shaping device to pre-shape four glass liquids with different formulations to obtain four pre-shaped glasses with different compositions. Then, the four pre-shaped glasses are stacked for secondary shaping. The formulations and shaping parameters are the same as in Example 1.

[0112] Because the preparation method described in this comparative example does not use the multilayer single crystal glass preparation device described in Example 1, but instead uses a traditional single-set shaping device to pre-shape four glass liquids of different formulations, and then to pre-shape four pre-shaped glasses, the time interval between the pre-shaping and the second shaping is relatively long. Before the second shaping, the pre-shaped glasses are basically formed, which makes it impossible for the four pre-shaped glasses with different compositions to form a better transition interface or even to bond tightly during the second shaping process, thus failing to achieve the gradient color effect. In addition, this preparation method cannot achieve continuous production and is time-consuming, resulting in low production efficiency.

[0113] In summary, the multilayer microcrystalline glass shaping device provided by this invention, through the design and installation of a material guiding component with heat-insulating elements, and the use of a first shaping clamp and a second shaping clamp, allows glass melts of different compositions to be pre-shaped and then each pre-shaped glass material to be shaped a second time. Combined with the control of the composition of different glass raw materials by the preparation method, the device works together to achieve the control of color and transparency of each layer, realize the continuous production of multilayer lithium disilicate microcrystalline glass, improve production efficiency, and meet the market demand for gradient or multi-layer colored microcrystalline glass.

[0114] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A multi-layered microcrystalline glass shaping apparatus, characterized by, The multilayer glass-ceramic shaping device comprises a melting and cooling unit, a material guiding unit and a shaping unit connected in sequence from top to bottom; The melting and cooling unit comprises m melting and cooling assemblies arranged side by side; the material guiding unit comprises n material guiding components; the outer side of each material guiding component is further provided with a heat preservation component; the shaping unit comprises a first shaping assembly and a second shaping assembly arranged at the lower part of the first shaping assembly; the first shaping assembly comprises p first shaping clamps, and m = n = p ≥ 2; The first discharge port of the melting and cooling assembly is connected with the inlet of the material guiding component, and the outlet of the material guiding component is connected with the first shaping clamp.

2. The multi-layered microcrystalline glass shaping apparatus according to claim 1, wherein, The melting and cooling assembly comprises a melting assembly and a cooling assembly arranged at the lower part of the melting assembly; Preferably, the melting assembly comprises an insulating shell, a first heating component and a melting container; the melting container is arranged inside the insulating shell; the first heating component is arranged in the cavity between the insulating shell and the melting container; Preferably, the bottom of the melting container is provided with a second discharge port; Preferably, the cooling assembly comprises a cooling container and a second heating component arranged at the outer circumferential side of the cooling container; Preferably, the first discharge port is arranged at the bottom of the cooling container.

3. The multi-layered glass-ceramic shaping device according to claim 1 or 2, characterized in that The first shaping assembly further comprises a first shrinkage component arranged at the outer side of each first shaping clamp; Preferably, the second shaping assembly comprises a second shaping clamp and a second shrinkage component arranged at the outer side of the second shaping clamp; Preferably, the material of the first shaping clamp and the second shaping clamp comprises any one or a combination of at least two of stainless steel, cast iron, platinum and graphite; Preferably, the edge shape of the first shaping clamp comprises any one of straight shape, zigzag shape, wave shape, concave arc shape or convex arc shape; Preferably, the shape of the second clamp comprises a rectangle.

4. A method for preparing a multilayer lithium disilicate glass-ceramic, characterized in that, The preparation method adopts the multilayer glass-ceramic shaping device according to any one of claims 1-3 for shaping.

5. The preparation method according to claim 4, characterized in that, The preparation method comprises the following steps: Different components of glass raw materials are respectively melted and cooled, and the obtained mud-like glass liquid is respectively first shaped to obtain pre-shaped glass of different components, and then all the pre-shaped glass is stacked and simultaneously second shaped to obtain shaped glass, and then the shaped glass is subjected to crystallization treatment to obtain multilayer lithium disilicate glass-ceramics.

6. The production method according to claim 5, wherein According to the mass percentage, each glass raw material comprises SiO2 30-50wt%, Li2O 15-30wt%, K2O 3-10wt%, P2O5 0-10wt%, Ti2O 5-15wt%, Al2O3 0-5wt%, ZrO2 5-10wt%, CeO2 0-5wt%, B2O3 0-10wt%, ZnO 0-10wt% and colorant 0-10wt%; Preferably, the colorant comprises any one or a combination of at least two of V2O5, Er2O3, Pr6O 11 , Fe2O3, or NiO.

7. The preparation method according to claim 5 or 6, characterized in that, The melting temperature is 1350-1600℃; Preferably, the heat preservation time of the melting is 0.5-4h; Preferably, the atmosphere of the melting comprises air atmosphere and / or inert atmosphere; Preferably, the cooling temperature is 1050-1350℃; Preferably, the holding time of the cooling is 0.5-4h.

8. The method of any one of claims 5 to 7, wherein the method further comprises the step of: The pressure applied by the first shaping is 5-50N; Preferably, the pressure applied by the second shaping is 10-100N; Preferably, the preparation method further comprises, after the second shaping, shearing the shaped product to a target size to obtain a target shaped glass; Preferably, the preparation method further comprises, after the shearing, sequentially performing holding and cooling.

9. The method of any one of claims 5 to 8, wherein the method further comprises the step of: The crystallization treatment comprises sequentially performing heating and holding; Preferably, the terminal temperature of the heating is 600-900℃; Preferably, the rate of the heating is 5-15℃ / min; Preferably, the holding time is 0.5-60min.

10. A multilayer lithium disilicate microcrystalline glass, characterized in that, The multilayer lithium disilicate glass ceramic is prepared by the preparation method of any one of claims 4-9.

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