阅读说明：本技术 一种玻璃瓷及其制备方法 (Glass ceramic and preparation method thereof ) 是由 李伟达 于 2021-09-09 设计创作，主要内容包括：本发明公开了一种玻璃瓷及其制备方法,包括以下按重量份计的原料：粘土10～20份、石英10～20份和熔块60～80份；该玻璃瓷不选用废玻璃粉作为原料,采用同样具有透明质感的熔块替代玻璃粉,再配以粘土以增强生坯的强度,以及加入石英来提高坯体的烧制温度并降低成本,使得符合后续装饰釉料的温度要求,从而达到延长生坯保存时间,提高生坯坯体强度、提高成品的烧制温度以及成品烧成白度且易保持稳定性的效果。本发明通过以下步骤制备玻璃瓷：混料、球磨、造粒、干燥、模压成型、坯面装饰和烧制半成品,适应性地采用干法造粒工艺,通过球磨和造粒来限定原料的粒径,提高原料混合的均匀度,从而提高坯体成型过程中的合格率。(The invention discloses a glass ceramic and a preparation method thereof, wherein the glass ceramic comprises the following raw materials in parts by weight: 10-20 parts of clay, 10-20 parts of quartz and 60-80 parts of frit; the glass ceramic does not select waste glass powder as a raw material, adopts frit with the same transparent texture to replace the glass powder, is matched with clay to enhance the strength of a green body, and adds quartz to improve the firing temperature of the green body and reduce the cost, so that the temperature requirement of subsequent decorative glaze is met, and the effects of prolonging the storage time of the green body, improving the strength of the green body, improving the firing temperature of a finished product, and ensuring that the finished product is fired to be white and easy to keep stability are achieved. The invention prepares the glass ceramic by the following steps: mixing materials, ball milling, granulating, drying, compression molding, blank surface decoration and firing of semi-finished products, wherein a dry granulation process is adaptively adopted, the particle size of raw materials is limited through ball milling and granulation, and the uniformity of raw material mixing is improved, so that the qualification rate in the blank forming process is improved.)

1. The glass ceramic is characterized by comprising the following raw materials in parts by weight: 10-20 parts of clay, 10-20 parts of quartz and 60-80 parts of frit; the frit comprises the following raw materials in parts by weight: 50-55 parts of quartz sand, 5-10 parts of calcite, 15-20 parts of dolomite and 15-20 parts of soda ash.

2. The vitreous porcelain of claim 1, wherein the frit comprises the following raw materials in parts by weight: 50-55 parts of quartz sand, 5-10 parts of calcite, 15-20 parts of dolomite, 15-20 parts of soda ash and 1-2 parts of alumina.

3. The method for producing a vitreous china according to any one of claims 1 to 2, characterized by comprising the steps of:

1) mixing the raw materials according to the formula ratio to obtain a mixture;

2) ball-milling the mixture to obtain powder;

3) granulating the powder to obtain a green body raw material, and drying;

4) carrying out die pressing molding on the dried green blank raw material to obtain a green blank;

5) decorating the surface of the green body to obtain a semi-finished product;

6) firing the semi-finished product to obtain the glass ceramic.

4. The method for preparing a vitreous porcelain according to claim 3, wherein in the step 2), the ball milling is a dry ball milling.

5. The method for preparing a vitreous porcelain according to claim 3, wherein in the step 3), the granulation is dry granulation, and the specific operation of the granulation is as follows: and (3) grading the particles of the powder by combining a rotary granulation method and a spray granulation method to obtain a green blank raw material.

6. The method for producing a vitreous porcelain according to claim 3, wherein in step 3), the drying is fluidized drying.

7. The method for preparing a vitreous porcelain according to claim 6, wherein in the step 3), the moisture percentage of the dried green body raw material is 4 to 6%.

8. The method for preparing glass ceramic according to claim 3, wherein in the step 5), the decoration is one or more of ink-jet printing, glaze spraying and glaze pouring.

9. The method for producing a vitreous porcelain according to claim 3, wherein in the step 6), the firing temperature is 900 to 1100 ℃.

Technical Field

The invention relates to the technical field of glass ceramic products, in particular to a glass ceramic and a preparation method thereof.

Background

Due to various restrictions of China ceramic building materials in European and American markets in recent years, the demand of mosaic products which are made of glass and are similar to ceramic but not made of ceramic is greatly increased, and a new mosaic product called glass porcelain mosaic comes into play. The market demands the "glass porcelain" products mainly have two points: firstly, the material is determined to be glass; secondly, the surface decoration effect is close to or better than that of the similar products made of the traditional ceramic materials, namely the customer requirements accumulated before the original years can be completely replaced.

Most manufacturers on the market adopt glass powder processed by taking waste glass as a raw material to produce a glass porcelain product in a dry pressing mode. The raw material formula and the process have the following defects:

a: the green body prepared by only taking the glass powder as a main raw material has extremely poor strength, and the raw material storage time is extremely short (generally not longer than 6 hours); the production requirements of intermittent production and one-time firing of glaze spraying decoration cannot be realized;

b: a large amount of waste glass is used as a raw material source, so that the quality of the raw material is difficult to maintain long-term stability (mainly whiteness);

c: because the melting point of the existing waste glass material in the market is extremely low (generally lower than 750 ℃), the original decorative glaze applied to the ceramic material blank is difficult to adapt to the extremely low temperature requirement, so that a plurality of ceramic products are limited, and a substitute cannot be found;

d: because the waste glass powder has extremely strong surface activity and the powder has extremely strong lubricity, a screw of a granulator can slip, so that the formula material is difficult to adapt to an advanced dry powder granulation process, the stability of the blank quality is greatly influenced in the dry pressing granulation process, the qualification rate of products is reduced at most, and the production cost is increased.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide the glass ceramic which can effectively improve the strength and the melting point of a green body, reduce the cost and does not influence the judgment standard which takes a glass material as a main body; the second purpose of the invention is to provide a preparation method of the glass ceramic, which adopts a dry granulation process to prepare the glass ceramic, and improves the uniformity of raw material mixing, thereby improving the qualification rate of the formed green body.

One of the purposes of the invention is realized by adopting the following technical scheme:

the glass ceramic comprises the following raw materials in parts by weight: 10-20 parts of clay, 10-20 parts of quartz and 60-80 parts of frit; the frit comprises the following raw materials in parts by weight: 50-55 parts of quartz sand, 5-10 parts of calcite, 15-20 parts of dolomite and 15-20 parts of soda ash.

Further, the frit comprises the following raw materials in parts by weight: 50-55 parts of quartz sand, 5-10 parts of calcite, 15-20 parts of dolomite, 15-20 parts of soda ash and 1-2 parts of alumina.

The second purpose of the invention is realized by adopting the following technical scheme:

the preparation method of the glass ceramic comprises the following steps:

1) mixing the raw materials according to the formula ratio to obtain a mixture;

2) ball-milling the mixture to obtain powder;

3) granulating the powder to obtain a green body raw material, and drying;

4) carrying out die pressing molding on the dried green blank raw material to obtain a green blank;

5) decorating the surface of the green body to obtain a semi-finished product;

6) firing the semi-finished product to obtain the glass ceramic.

Further, in the step 2), the ball milling is dry ball milling.

Further, in step 3), the granulation is dry granulation, and the specific operations of granulation are as follows: and (3) grading the particles of the powder by combining a rotary granulation method and a spray granulation method to obtain a green blank raw material.

Further, in step 3), the drying is fluidized drying.

Further, in the step 3), the moisture percentage of the dried green body raw material is 4-6%.

Further, in the step 5), the decoration mode is one or a combination of more than two of inkjet printing, glaze spraying and glaze pouring.

Further, in the step 6), the firing temperature is 900-1100 ℃.

Compared with the prior art, the invention has the beneficial effects that:

(1) the main components of the glass ceramic are only three types, namely frit, clay and quartz, waste glass powder is not selected as a raw material, the frit with the same transparent texture is used for replacing the glass powder, the clay is added to enhance the strength of a green body, and the quartz is added to improve the firing temperature of the green body and greatly reduce the cost of the raw material, so that the temperature requirement of subsequent decorative glaze is met, the storage time of the green body is prolonged, the strength of the green body is improved, the firing temperature of a finished product is improved, the firing whiteness of the finished product is improved, and the stability is easy to maintain.

(2) The invention prepares the glass ceramic by the following steps: the glass ceramic can be prepared by adopting a dry granulation process adaptively, the particle size of raw materials is limited by ball milling and granulation, the uniformity of the raw material mixing is improved, and the qualification rate of the blank in the forming process is improved.

(3) The glass porcelain prepared by the formula and the preparation method can be stored for 3-6 days without deterioration, the storage time of the green body (semi-finished product) can reach more than 72 hours, the requirements of glaze decoration time and flexible scheduling are met, the requirement of intermittent production is met, and energy waste is avoided; the green body strength of the green body reaches 0.5-0.6 mpa, while the general glass powder product is less than 0.2mpa, the green body can meet the requirements of transportation and surface decoration in the production process when the glass powder product is touched and scattered; the firing temperature range of the semi-finished product is 900-1100 ℃, the requirement of the market glazing temperature is met, the development breadth of the product is enhanced, the firing whiteness of the glass ceramic finished product can reach over 74 ℃, the stability is easy to maintain, and compared with the glass ceramic product which is prepared by taking glass powder as a raw material and has the advantages of unstable firing whiteness below 65 ℃, the performance is better, and the market value is higher.

Detailed Description

The present invention is further described below with reference to specific embodiments, and it should be noted that, without conflict, any combination between the embodiments or technical features described below may form a new embodiment.

Example 1

The glass ceramic comprises the following raw materials in parts by weight: 10 parts of clay, 10 parts of quartz and 80 parts of frit. The frit comprises the following raw materials in parts by weight: 50 parts of quartz sand, 5 parts of calcite, 15 parts of dolomite, 15 parts of soda ash and 1 part of alumina.

The preparation method of the glass ceramic comprises the following steps:

1) mixing the raw materials according to the formula ratio to obtain a mixture;

2) ball-milling the mixture in a dry ball mill to obtain powder;

3) dry granulation is carried out on the powder, and the specific operation is as follows: classifying the particles of the powder by combining a rotary granulation method and a spray granulation method to obtain a green blank raw material; after a green body raw material is obtained, carrying out fluidized drying until the moisture percentage of the green body raw material is 4%;

4) carrying out die pressing molding on the dried green blank raw material to obtain a green blank;

5) carrying out glaze spraying decoration on the surface of the green body to obtain a semi-finished product;

6) firing the semi-finished product at 1005 ℃ to obtain the glass ceramic.

Example 2

The glass ceramic comprises the following raw materials in parts by weight: clay 20 parts, quartz 20 parts and frit 60 parts. The frit comprises the following raw materials in parts by weight: 55 parts of quartz sand, 10 parts of calcite, 20 parts of dolomite, 20 parts of soda ash and 2 parts of alumina.

The preparation method of the glass ceramic comprises the following steps:

1) mixing the raw materials according to the formula ratio to obtain a mixture;

2) ball-milling the mixture in a dry ball mill to obtain powder;

3) dry granulation is carried out on the powder, and the specific operation is as follows: classifying the particles of the powder by combining a rotary granulation method and a spray granulation method to obtain a green blank raw material; after a green body raw material is obtained, carrying out fluidized drying until the moisture percentage of the green body raw material is 6%;

4) carrying out die pressing molding on the dried green blank raw material to obtain a green blank;

5) performing glaze spraying decoration on the surface of the green body to obtain a semi-finished product;

6) firing the semi-finished product at 1000 ℃ to obtain the glass ceramic.

Example 3

The glass ceramic comprises the following raw materials in parts by weight: clay 20 parts, quartz 20 parts and frit 80 parts. The frit comprises the following raw materials in parts by weight: 55 parts of quartz sand, 5 parts of calcite, 15 parts of dolomite, 15 parts of soda ash and 1 part of alumina.

The preparation method of the glass ceramic comprises the following steps:

1) mixing the raw materials according to the formula ratio to obtain a mixture;

2) ball-milling the mixture in a dry ball mill to obtain powder;

3) dry granulation is carried out on the powder, and the specific operation is as follows: classifying the particles of the powder by combining a rotary granulation method and a spray granulation method to obtain a green blank raw material; after a green body raw material is obtained, carrying out fluidized drying until the moisture percentage of the green body raw material is 5%;

4) carrying out die pressing molding on the dried green blank raw material to obtain a green blank;

5) performing ink-jet printing decoration on the surface of the green body to obtain a semi-finished product;

6) firing the semi-finished product at 995 ℃ to obtain the glass ceramic.

Comparative example 1

Comparative example 1 differs from example 1 in that: in comparative example 1, the frit was replaced with an equal amount of glass frit.

Comparative example 2

Comparative example 2 differs from example 1 in that: comparative example 2 no quartz was added. The remaining components and preparation were the same as in example 1.

Comparative example 3

Comparative example 3 differs from example 1 in that: comparative example 3 no clay was added. The remaining components and preparation were the same as in example 1.

Comparative example 4

Comparative example 4 differs from example 1 in that: comparative example 4 did not include the high speed granulation step and the remaining steps and starting materials were the same as in example 1.

Performance testing

1. Storage time testing of green bodies: the green compacts prepared in examples 1 to 3 and comparative examples 1 to 4 after the step of die press forming were taken out, placed at normal temperature, and tested for the time at which cracking occurred.

2. Green strength of green body: the semi-finished products prepared in examples 1 to 3 and comparative examples 1 to 4 after the step of die press forming were taken out, and the strength of the green body was measured, as shown in table 1.

TABLE 1 Stable storage time and Green body Strength of the semi-finished products of examples 1 to 3 and comparative examples 1 to 4

	Stable storage time h	Green strength MPa
			Example 1	96	0.6
Example 2	120	0.62
			Example 3	144	0.62
Comparative example 1	0.2	0.1
			Comparative example 2	10	0.37
Comparative example 3	6	0.13
			Comparative example 4	4.8	Go to waste after mildewing

3. Measuring the firing temperature of the glass ceramic: firstly, the finished glass porcelain products of the embodiments 1 to 3 and the comparative examples 1 to 4 are cut, glaze is ground off on a grinding machine, the cut glass porcelain products are processed into strips of 5 multiplied by 35mm, then the strips are placed on a high-temperature expansion instrument, the expansion curve is automatically recorded while heating, when the heating temperature reaches the original sintering temperature of a sample, as more glass phases are generated in the blank body, the trend of the expansion curve can be changed to a certain extent, and the temperature at the moment can be used as the sintering temperature of the ancient ceramics. The firing temperatures reported are in table 2.

4. Measuring the fired whiteness of the glass ceramic: the whiteness of the glass ceramics of the examples 1-3 and the comparative examples 1-4 is measured by adopting a QB/T1503-2011 domestic ceramic whiteness measurement method standard, and particularly, the surfaces of the glass ceramics of the examples 1-3 and the comparative examples 1-4 which are inspected are not subjected to decoration treatment. Specifically, as shown in table 2.

TABLE 2 firing temperature and whiteness of finished products of examples 1 to 3 and comparative examples 1 to 7

As can be seen from Table 1, the stable storage time of the green body in the embodiment 1-3 is higher than 96h, the strength of the green body is higher than 0.6MPa, the glaze decoration time is sufficient, the intermittent production requirement can be realized, the production scheduling is flexible, and the transportation requirement and the surface decoration requirement in the production process can be met. In the comparative example 1, the glass powder is used for replacing the frit to prepare the glass porcelain, the storage time of the green body is far shorter than that of the glass porcelain prepared in the examples 1-3, the production requirements of intermittent production and one-time firing of glaze spraying decoration cannot be met, the green body strength of the green body is low, the green body touches the frame, and the load of transfer is increased. The storage stability time of comparative example 2 without quartz and comparative example 3 without clay were shorter than those of examples 1 to 3, which shows that the combination of clay, quartz and frit in examples 1 to 3 can greatly prolong the green storage time and green strength. In comparative example 3, the green strength was lower than that of comparative example 2 because no clay was added. In contrast, in comparative example 4, the glass ceramic was obtained by direct compression molding, surface decoration and firing without a granulation step, the raw material mixing uniformity was low, which resulted in raw material agglomeration and affected the molding of the glass ceramic finished product, and the green body was mildewed after standing for 4 hours, indicating that the raw material mixing uniformity is an important criterion for determining the yield of the molded green body.

As shown in Table 2, the firing temperatures of the glass ceramics of examples 1 to 3 are higher than 900 ℃ and the common firing temperature of the glaze is 900 ℃, so that the firing temperatures of examples 1 to 3 and comparative example 4 can meet the requirements. The whiteness of the finished products of examples 1-3 was higher than 70 degrees. The firing temperature and the firing whiteness of the vitreous china of comparative examples 1 to 4 were lower than those of examples 1 to 3. Because comparative example 1 replaces the frit with waste glass having a low melting point, making the firing temperature of the vitreous china of comparative example 1 only 720 ℃, makes it difficult for the decorative glaze to accommodate this excessively low temperature requirement. The firing temperature was lowered in both comparative example 2 where no quartz was added and comparative example 3 where no clay was added, indicating that the deletion of the ingredients affected the firing temperature and the whiteness of the ingredients. Comparative example 4 the glass ceramic was obtained by direct compression molding, surface decoration and firing without a granulation step, and the raw material mixing uniformity was low, resulting in raw material agglomeration, affecting the molding of the glass ceramic finished product, and thus affecting the whiteness of the product.

In conclusion, the glass ceramic with long stable storage time, high green body strength, high firing temperature and high fired whiteness can be prepared by combining the formula and the preparation method of the glass ceramic.

The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.