阅读说明：本技术 一种硅溶胶增强的超白薄型陶瓷板及其制备方法 (Silica sol reinforced ultra-white thin ceramic plate and preparation method thereof ) 是由 刘一军 王贤超 程科木 谢范峰 于 2021-08-13 设计创作，主要内容包括：本发明公开一种硅溶胶增强的超白薄型陶瓷板及其制备方法。所述硅溶胶增强的超白薄型陶瓷板的坯体原料包括：以质量百分比计,粘土20-25%、超白砂50-60%、烧滑石3-6%、煅烧氧化铝3-6%、长石3-24%、硅溶胶10-20%。本发明提出在薄型陶瓷板的配方中引入硅溶胶,在实现高白度的基础上,有效增加陶瓷板的湿坯强度,减少陶瓷板在干燥工序前的破损,还可以借助硅溶胶与其他坯体原料在烧成过程中反应原位增强薄型陶瓷板成品的力学性能。(The invention discloses a silica sol reinforced ultra-white thin ceramic plate and a preparation method thereof. The body raw materials of the silica sol reinforced ultra-white thin ceramic plate comprise: 20-25% of clay, 50-60% of super white sand, 3-6% of calcined talc, 3-6% of calcined alumina, 3-24% of feldspar and 10-20% of silica sol. According to the invention, silica sol is introduced into the formula of the thin ceramic plate, so that on the basis of realizing high whiteness, the wet blank strength of the ceramic plate is effectively increased, the damage of the ceramic plate before a drying process is reduced, and the mechanical property of a finished product of the thin ceramic plate can be enhanced in situ by means of the reaction of the silica sol and other blank raw materials in a sintering process.)

1. A silica sol reinforced ultra-white thin ceramic plate is characterized in that the blank raw materials of the silica sol reinforced ultra-white thin ceramic plate comprise: 20-25% of clay, 50-60% of super white sand, 3-6% of calcined talc, 3-6% of calcined alumina, 3-24% of feldspar and 10-20% of silica sol.

2. The silica sol reinforced super white thin ceramic plate according to claim 1, wherein the iron oxide content in the body chemical composition of the silica sol reinforced super white thin ceramic plate is below 0.2 wt%.

3. The silica sol reinforced super white thin ceramic plate of claim 2, wherein a green body chemical composition of the silica sol reinforced super white thin ceramic plate comprises: by mass percentage, loss of ignition is 4-5%, and SiO₂ 63-67%、Al₂O₃19-22%、Fe₂O₃ 0.1-0.2%、TiO₂ 0.03-0.05%、CaO 2-2.5%、MgO 2-2.5、K₂O 2-2.5%、Na₂O 1.5-2%。

4. A silica sol reinforced ultra-white thin ceramic plate according to any one of claims 1 to 3, wherein the ultra-white thin ceramic plate has a wet green strength of 0.45 to 0.55MPa and a dry green strength of 2.5 to 3.0 MPa.

5. The silica sol reinforced super white thin ceramic plate according to any one of claims 1 to 4, wherein the super white thin ceramic plate has a modulus of rupture of 50 to 60MPa and a bulk density of 2.43 to 2.46g/cm³。

6. The silica sol reinforced super white thin ceramic plate according to any one of claims 1 to 5, wherein the whiteness of the super white thin ceramic plate is 78-83 degrees.

7. The silica sol reinforced super white thin ceramic plate as claimed in any one of claims 1 to 6, wherein the silica sol reinforced super white thin ceramic plate has a specification of 1800-.

8. The method for preparing a silica sol reinforced ultra-white thin ceramic plate according to any one of claims 1 to 7, wherein the preparing comprises: weighing the raw materials according to the raw material composition of the blank, and then carrying out wet ball milling, sieving and drying to obtain blank powder; pressing and molding the blank powder into a wet blank, and drying the wet blank to obtain a dry blank; and firing the dry blank to obtain the silica sol reinforced ultra-white thin ceramic plate.

9. The method as claimed in claim 8, wherein the maximum firing temperature is 1160-1180 ℃ and the firing time is 40-60 min.

10. The production method according to claim 8 or 9, characterized by further comprising: and glazing the surface of the dry blank before firing.

Technical Field

The invention relates to a silica sol reinforced ultra-white thin ceramic plate and a preparation method thereof, belonging to the technical field of ceramic tile production and manufacturing.

Background

In order to ensure that the bricks are not rotten in the production and routing process of the thin ceramic plate, the method mainly adopted at present is to increase the clay consumption of the thin ceramic plate to increase the green strength of a blank body. However, the shortage of high-performance clay resources leads to high clay prices. And the high iron content of the clay makes thin ceramic plates poor in whiteness.

Disclosure of Invention

Aiming at the problems, the invention provides that silica sol is introduced into the formula of the thin ceramic plate, so that on the basis of realizing high whiteness, the wet blank strength of the ceramic plate is effectively increased, the damage of the ceramic plate before the drying process is reduced, and the mechanical property of the finished product of the thin ceramic plate can be enhanced in situ by means of the reaction of the silica sol and other blank raw materials in the sintering process.

In a first aspect, the present invention provides a silica sol reinforced ultra-white thin ceramic plate. The body raw materials of the silica sol reinforced ultra-white thin ceramic plate comprise: 20-25% of clay, 50-60% of super white sand, 3-6% of calcined talc, 3-6% of calcined alumina, 3-24% of feldspar and 10-20% of silica sol.

Preferably, the iron oxide content in the blank chemical composition of the silica sol reinforced ultra-white thin ceramic plate is less than 0.2 wt%. By controlling the iron content of the blank within the range, the high whiteness of the ceramic plate is favorably realized, so that the glazing process is conveniently simplified.

Preferably, the body chemical composition of the silica sol reinforced ultra-white thin ceramic plate comprises: by mass percentage, loss of ignition is 4-5%, and SiO₂ 63-67％、Al₂O₃ 19-22％、Fe₂O₃ 0.1-0.2％、TiO₂ 0.03-0.05％、CaO 2-2.5％、MgO 2-2.5、K₂O 2-2.5％、Na₂O 1.5-2％。

Preferably, the wet blank strength of the ultra-white thin ceramic plate is 0.45-0.55MPa, and the dry blank strength is 2.5-3.0 MPa.

Preferably, the modulus of rupture of the ultra-white thin ceramic plate is 50-60MPa, and the bulk density is 2.43-2.46g/cm³。

Preferably, the whiteness of the ultra-white thin ceramic plate is 78-83 degrees.

Preferably, the silica sol reinforced super white thin ceramic plate has the specification of 1800-2400mm long, 900-1800mm wide and 3-6mm thick.

In a second aspect, the present invention provides a method for preparing a silica sol reinforced ultra-white thin ceramic plate as described in any one of the above. The preparation comprises the following steps: weighing the raw materials according to the raw material composition of the blank, and then carrying out wet ball milling, sieving and drying to obtain blank powder; pressing and molding the blank powder into a wet blank, and drying the wet blank to obtain a dry blank; and firing the dry blank to obtain the silica sol reinforced ultra-white thin ceramic plate.

Preferably, the maximum firing temperature is 1160-1180 ℃, and the firing time is 40-60 min.

Preferably, the preparation method further comprises: and glazing the surface of the dry blank before firing. Because the silica sol reinforced ultra-white thin ceramic plate has extremely high whiteness, the glaze is not required to be applied to cover the ground color of the blank body when the dry blank is glazed for decoration.

Preferably, the preparation method further comprises: directly carrying out ink-jet printing on the surface of the dry blank to form a design pattern before firing; preferably, protective glaze is applied on the surface of the dry blank after the design pattern is printed by ink-jet printing; more preferably, the chemical composition of the protective glaze comprises: by mass percent, SiO₂ 50-55％、Al₂O₃ 10-15％、CaO 8-15％、MgO 2.5-3.2％、ZnO 2-3％、K₂O 2-3％、Na₂O2-3%, loss on ignition 0.3-0.5%; further preferably, the protective glaze is applied by spraying glaze and has a specific gravity of 1.25-1.45g/cm³The application amount is 200-²。

Drawings

Fig. 1 is a flow chart illustrating a process for preparing a silica sol reinforced ultra-white thin ceramic plate according to an embodiment of the present invention.

Detailed Description

The present invention is further illustrated by the following examples, which are to be understood as merely illustrative of, and not restrictive on, the present invention. Unless otherwise specified, each percentage means a mass percentage.

The following is an exemplary description of a method for manufacturing a silica sol reinforced ultra-white thin ceramic plate (hereinafter, referred to as "ultra-white thin ceramic plate") according to the present invention.

Preparing a blank raw material of the ultra-white thin ceramic plate. The blank raw materials comprise: 20-25% of clay, 50-60% of super white sand, 3-6% of calcined talc, 3-6% of calcined alumina, 3-24% of feldspar and 10-20% of silica sol. Preferably, the sum of the mass percentages of the blank raw materials is 100%. The silica sol may have a silica content of 25-35% by mass. Such clays include, but are not limited to, kaolin, bentonite, and the like. The feldspar includes but is not limited to potassium feldspar, albite, etc.

Weighing the raw materials according to the composition of the raw materials, performing wet ball milling, sieving and drying to obtain blank powder. By introducing a proper amount of silica sol into the blank raw material, the silica sol particles are coated on the surfaces of other raw materials to form a coating structure during ball milling and mixing, and the coating structure is filled in the particle gaps of the raw materials in the subsequent compression molding, so that the wet blank strength of the blank is obviously enhanced.

The invention controls the mass percent of the silica sol to be 10-20%, and can effectively increase the green body strength. However, when the silica in the silica sol undergoes phase transformation at high temperature to generate quartz-type silica, and the mass percentage of the silica sol is greater than 20%, the crystal type transformation affects the volume shrinkage of the ceramic plate and even deteriorates the compactness of the blank, thereby causing the mechanical properties of the ceramic plate to be sharply reduced.

Organic reinforcing agents can also be additionally added into the green body. In some embodiments, the organic reinforcing agent is 0.5-0.8% by mass of the green body starting material. The organic enhancer may be selected from commercially available organic enhancers commonly used in the art.

And pressing and molding the blank powder to obtain a wet blank. The method of press molding is not limited, and for example, dry press molding may be performed. In some embodiments, the wet green strength is from 0.45 to 0.55 MPa.

And drying the wet blank to obtain a dry blank. The dry blank strength can be 2.5-3.0 MPa. The drying condition can be the drying condition commonly used for the wet blank in the ceramic field, for example, the drying temperature is 200-250 ℃, and the drying time is 20-30 min.

It is stated that the invention is to introduce silica sol into the plastic formulation to enhance the bonding performance, as opposed to introducing a small amount of silica sol into a ceramic slab that is made of a ridged material (e.g., tailings) as the main raw material. That is, the silica sol is introduced into the plastic formula, so that the bonding performance of the silica sol can be exerted, more importantly, the use of the silica sol can improve the wet blank strength and whiteness of the blank under the condition of obviously reducing the clay usage amount, the damage of the blank before the drying process is greatly reduced, the consumption of clay mineral raw materials is reduced, and the high industrial application value and economic benefit are achieved. In some embodiments, the whiteness of the blank of the ultra-white thin ceramic plate is 78-83 degrees, which is obviously improved compared with the whiteness of the existing ultra-white thin ceramic plate (the whiteness is usually about 60 degrees).

And firing the dry blank. The maximum firing temperature is 1160-1180 ℃, and the firing time is 40-60 min.

Compared with the reinforced ceramic plate with the silica sol coating sprayed on the surface of the dry blank, the reinforced ceramic plate has the advantages that the silica sol is introduced into the formula of the plastic blank for reinforcement, so that the strength of the wet blank of the ceramic plate can be enhanced to avoid cracking of the wet blank in the production line transportation process before the wet blank enters the drying process, and the silica sol is coated on the surfaces of other particles of the raw materials of the blank, so that the reaction is promoted and the volume shrinkage is effectively controlled due to the mutual contact of the raw materials in the sintering process, and the mechanical property of the finished ceramic plate is further enhanced. In some embodiments, the firing shrinkage of the ultra-white thin ceramic plate is 10 to 12%. The firing shrinkage is the size change rate before and after firing, and the calculation formula is as follows: the firing shrinkage ratio (size before firing-size after firing)/size before firing.

The dried blank may also be decorated prior to firing. Such as ink jet printing a design on the surface of the dry blank. It is often necessary to apply a cover coat to the surface of the green body to mask the green body's undertones and blemishes prior to ink-jet printing the design on the surface of the green body. The blank body of the thin ceramic plate has high whiteness, subsequent decoration can be carried out without applying overglaze on the surface of the ceramic plate, and the ceramic plate is prevented from cracking in the process of moving the ceramic plate along a glaze line due to the introduction of a large amount of water during glazing while the glazing process is simplified.

And protective glaze can be applied to the surface of the dry blank after the design pattern is printed by ink jet. The protective glaze is applied to protect the ink jet printed design from abrasion and to increase the color development of the design.

The chemical composition of the protective glaze may include: by mass percent, SiO₂ 50-55％、Al₂O₃ 10-15％、CaO 8-15％、MgO 2.5-3.2％、ZnO 2-3％、K₂O 2-3％、Na₂O2-3% and loss of ignition 0.3-0.5%.

The protective glaze can be applied by spraying glaze. In some embodiments, the protective glaze has a specific gravity of 1.25 to 1.45g/cm³The application amount is 200-². The glaze surface of the protective glaze is relatively flat within the range, and the phenomena of missing polishing and the like can be avoided.

The present invention will be described in detail by way of examples. It is also to be understood that the following examples are illustrative of the present invention and are not to be construed as limiting the scope of the invention, and that certain insubstantial modifications and adaptations of the invention by those skilled in the art may be made in light of the above teachings. The specific process parameters and the like of the following examples are also only one example of suitable ranges, i.e., those skilled in the art can select the appropriate ranges through the description herein, and are not limited to the specific values exemplified below.

Example 1

The preparation method of the silica sol reinforced ultra-white thin ceramic plate comprises the following steps:

weighing and ball-milling to prepare blank powder; the raw material composition of the ultra-white thin ceramic plate comprises: clay, by mass percent: 20-25% of super white sand: 50-60%, burnt talc: 3-6%, calcined alumina: 3-6% of feldspar: 3-24%, silica sol: 10 to 20 percent; weighing the raw materials according to the raw material composition of the green body powder, carrying out wet ball milling on the raw materials, sieving the raw materials, and drying the raw materials to obtain green body powder;

pressing and molding the blank powder by using a press to obtain a wet blank;

drying the wet blank at the drying temperature of 200-250 ℃ for 20-30min to obtain a dry blank;

firing; the maximum firing temperature is 1160-1180 ℃, and the firing time is 40-60 min.

The wet green strength, dry green strength, modulus of rupture, bulk density were tested according to GBT 23266-2009.

The ultra-white thin ceramic plate has the wet blank strength of 0.45-0.55MPa, the dry blank strength of 2.5-3.0MPa, the modulus of rupture of 50-60MPa and the bulk density of 2.43-2.46g/cm³The whiteness is 78-83 degrees.

Example 2

The preparation method of the silica sol reinforced ultra-white thin ceramic plate comprises the following steps:

weighing and ball-milling to prepare blank powder; the raw material composition of the ultra-white thin ceramic plate comprises: clay, by mass percent: 20-25% of super white sand: 50-60%, burnt talc: 3-6%, calcined alumina: 3-6% of feldspar: 3-24%, silica sol: 10 to 20 percent; weighing the raw materials according to the raw material composition of the green body powder, carrying out wet ball milling on the raw materials, sieving the raw materials, and drying the raw materials to obtain green body powder;

pressing and molding the blank powder by using a press to obtain a wet blank;

drying the wet blank at the drying temperature of 200-250 ℃ for 20-30min to obtain a dry blank;

printing a design pattern on the surface of the dry blank in an ink jet mode;

applying protective glaze on the surface of the dry blank after the design pattern is printed by ink jet; the chemical composition of the protective glaze comprises: by mass percent, SiO₂ 50-55％、Al₂O₃ 10-15％、CaO 8-15％、MgO 2.5-3.2％、ZnO 2-3％、K₂O 2-3％、Na₂O2-3%, loss on ignition 0.3-0.5%; the specific gravity of the protective glaze is 1.25-1.45g/cm³The application amount is 200-²(ii) a Firing; the highest firing temperature is 1160-1180 ℃, and the firing time is 40-60 min;

the mechanical properties of the ultra-white thin ceramic plate were substantially the same as those of example 1.

Comparative example 1

Essentially the same as example 1, except that: the thin ceramic plate comprises the following raw materials: 20% of clay, 20% of super white sand: 45%, calcined talc: 3%, calcined alumina: 3% and feldspar: 24%, silica sol: 5 percent.

The wet green strength of comparative example 1 was significantly reduced, and a large number of rotten bricks appeared during the routing process, thereby failing to perform the relevant performance tests.

Comparative example 2

Essentially the same as example 1, except that: the thin ceramic plate comprises the following raw materials: 20% of clay, 20% of super white sand: 30%, calcined talc: 3%, calcined alumina: 3% and feldspar: 19%, silica sol: 25 percent.

The finished thin ceramic plate of comparative example 2 had a modulus of rupture of about 45 MPa. The mechanical properties of the finished ultra-white thin ceramic plate are deteriorated because a large amount of silica in the silica sol undergoes phase change at high temperature to generate quartz-type silica, thereby seriously affecting the compactness of the blank.

Comparative example 3

Essentially the same as example 1, except that: the thin ceramic plate comprises the following raw materials: clay, by mass percent: 35-45% of super white sand: 35-40%, burnt talc: 3-6%, calcined alumina: 0-2%, feldspar: 7 to 27 percent.

The thin ceramic plate has high mechanical properties, but the whiteness is only about 60 degrees, because the whiteness of the ceramic plate is limited due to the fact that the iron oxide content in the composition of the thin ceramic plate is high due to a large amount of clay.