JP2000239041A - Surface treated dried glaze raw material powder and apparatus for automatically producing glaze - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a raw material powder capable of readily mixing and producing a glaze by operations in a short time without causing a secondary aggregation in an aqueous solution even when being stored by carrying out pulverization until a specific value of particle diameter is obtained for every glaze raw material having silicate groups, mixing a surfactant for every aqueous solution, then drying the resultant slurry as an intact fine powder and further applying a surfactant to the surface thereof. SOLUTION: Pulverization of a glaze raw material having silicate groups such as quartzite, feldspar or frit is carried out until the particle diameter becomes, e.g. average 0.1-10 μm for every raw material and at least a low-molecular weight surfactant in an amount of 0.05-5% based on the surface area is mixed for every aqueous solution and stirred. The resultant slurry is then dried as an intact fine powder with the surfactant applied thereto by a spray dryer, etc. Furthermore, a high-molecular weight surfactant in an amount of 0.05-5 wt.% together with the low-molecular weight surfactant can be mixed. A glaze can be produced simply by charging the surface treated dried glaze raw material powder produced by the method into water together with other glaze raw materials and stirring the resultant mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-treated dry glaze raw material powder which is capable of efficiently producing a glaze simply by mixing a finely ground glaze raw material into a powder by surface treatment and mixing and stirring with a pigment or other glaze raw material. And an automatic glaze producing apparatus using the dried glaze raw material powder.

[0002]

2. Description of the Related Art In the case of ceramics, for example, in the case of tiles, granulated clay is pressed into a product shape, a glaze is spread on the molded product by coating or the like, and then the dried product is fired. It has become. This glaze is a kind of glassy material that covers the ceramic body. It not only gives color and smoothness to the surface of the ceramic and gives it an aesthetic effect, but also prevents the penetration of water and liquid into the body. It is widely used to increase resistance to chemicals and increase the strength of ceramics. The main component of the glaze is a silicate compound, and the method of adjusting the glaze is based on the manufacture of glaze raw materials such as silica, feldspar, lime, frit, lead compounds, clay, and calcium carbonate having an average particle size of about 15 to 30 μm. From a ceramic manufacturer, and water and additives are added at the ceramic manufacturing site, the glaze raw material is finely pulverized by a ball mill to about 5 μm, and a clay imparting agent, a binder, etc. are added to the uniformly mixed slurry. The components are uniformly dispersed to obtain a fluid such as an aqueous solution having an appropriate viscosity. The glaze finely pulverized to about 5 μm can also be stored. However, the glaze that has been stored is destabilized because the particles become unstable and the particles coagulate in an aqueous solution by a crosslinking reaction (silanolation reaction). When it was used again, it was difficult to re-disperse it just by stirring, so it was necessary to re-pulverize it with a ball mill. Therefore, every time the type of glaze was changed, the ceramic manufacturer purchased silica stone having a particle size of about 15 to 30 μm, and delivered the glaze prepared by the glaze manufacturer into an aqueous solution to a ceramic manufacturing plant.

[0003]

However, a large number of ball mills must be installed in order to finely adjust the color of the delivered glaze at a porcelain factory.
In addition, the production line for ceramics is completely automated by the adoption of roller hearth kilns, whereas the adjustment of glaze requires a long time for crushing. In addition, the ball mill had to be prepared for the number of colors, and the ball mill had to be cleaned every time it was reground, and the washing water had to be disposed of as industrial waste.

[0004]

Therefore, according to the present invention, first, the first object of the present invention is to finely pulverize each glaze raw material having a silicate group until the average particle diameter becomes 0.1 to 10 μm. After mixing a surfactant for each aqueous solution, for example, dried as fine powder with a spray dryer,
A surface-treated dry glaze raw material powder characterized by having a surfactant adhered to the surface. Such a dried glaze raw material powder does not cause the phenomenon that the surface of the particles becomes unstable even when stored, and the surfactant causes secondary aggregation in an aqueous solution due to a cross-linking reaction (silanolation reaction). Therefore, long-term storage and light transport can be performed. When used as a glaze, the surface-treated silica stone and the separately surface-treated feldspar are mixed in water at a given ratio, together with a pigment or dispersant, etc., and stirred in a short period of time. Since the production and preparation are completed, it is no longer necessary to re-pulverize with a ball mill before applying the glaze as in the past. Also, if pigments etc. are dissolved for coloring,
By mixing and dissolving dry glaze raw material powders of different colors, a glaze of a different color can be manufactured, so that color mixing can be easily performed at a ceramic manufacturing site without a glaze manufacturer. At this time, if the surfactant is insufficient due to a pigment or the like added later, a low molecular surfactant, a high molecular surfactant, and an inorganic surfactant may be added. In the production line equipped with roller hearth kilns, this dry glaze raw material powder is stored for each type, and automatic production and application of glaze in accordance with the formulation command become possible. Labor saving was able to be promoted.

[0005] In particular, the particle size of silica or feldspar, which is a raw material for glaze, is finely pulverized to an average of about 0.1 to 10 µm, and at least a low molecular surfactant is added based on its surface area.
It is preferable to mix and stir the mixture in an amount of 5 to 5%, and to dry the mixture with a surfactant by a spray dryer or the like. Surfactants include low molecular weight, high molecular weight, low molecular weight and high molecular weight
There are types. Examples of the low molecular surfactant include polyoxyethylene alkyl ether, polyoxynonylphenyl ether, and propylene oxide. Further, together with the low-molecular surfactant, a high-molecular surfactant is used in an amount of 0.05 to
By mixing and stirring in an amount of 5%, the high molecular surfactant is disposed between the particles having the low molecular surfactant attached to the surface, whereby aggregation of the particles can be prevented. Examples of the polymer surfactant include sodium polycarboxylate. And when adding the surfactant, it is added after pulverization,
There are cases where it is agitated and dried and cases where it is pulverized and dried together after being added. Dispersants, polymeric dispersants and inorganic dispersants may be added. When the glaze raw material is talc or frit, it is wet pulverized and the average particle diameter is 0.1 to 10%.
μm, and mix at least low molecular surfactant in an amount of 0.05 to 5% based on the surface area.
By stirring and drying with the surfactant attached by a spray drier, a glaze suitable for electronic products can be provided. Even if the glaze raw material is talc or frit, in the case of dry pulverization, it has a function as a flux that melts at a low temperature.
Condensation due to the silanolation reaction does not occur even if it is larger than about 1 to 10 μm.

A second aspect of the present invention is a method for producing a glaze by simply putting the surface-treated dry glaze raw material powder and the other glaze raw material according to the first aspect into water and stirring the mixture to produce a glaze. It is. Here, simply stirring means that the conventional pulverizing step using a mill is unnecessary,
In a mill, the grinding claw slides or contacts the inner wall of the aquarium to abrade the large-diameter glaze material, whereas the stirring claw keeps the distance to the inner wall of the aquarium without sliding or contacting the inner wall of the aquarium. Is different. Further, a problem solving means according to claim 3 is an automatic manufacturing apparatus for glaze applied to ceramics and tiles before firing, a storage unit for storing the dry glaze raw material powder according to claim 1 and other glaze raw materials, Automatic glaze production with a measuring section that separates only the required amount, a charging section that puts it into water, a water tank section that dissolves the required amount of glaze just by mixing and stirring, and a cleaning section that carries out the glaze and cleans the inside Device.
This allows the glaze to be prepared immediately before the amount required for the glaze, so that it can be installed in an automatic firing line that handles a large variety of small quantities, and there is no need to dispose of extra glaze as in the past.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a process and an apparatus for producing a surface-treated dry glaze raw material powder according to the present invention will be described in detail. Silica, feldspar, lime, frit, lead compounds, clay, calcium carbonate, etc., which have a silicate group, such as quartzite, feldspar, frit, etc., and those which do not, are divided into two. Since those having a silicate group are sold in a state of an average particle size of about 15 to 30 μm, the purchased glaze raw material is put into a ball mill, and water and additives are added to make the glaze raw material average 0.1 μm. 1 to 10 μm, average 5 μ
and homogenized slurry is mixed. By adding a surfactant, a clay imparting agent, a binder, and the like, the additives are uniformly dispersed to obtain a fluid such as an aqueous solution having an appropriate viscosity. Note that sanitary ware or the like may have an average particle diameter of 2 to 3 μm, and the average particle diameter is adjusted depending on the base material to be glazed.

In the case of silica or feldspar, the particles are finely pulverized to an average particle size of about 0.1 to 10 μm, and the surfactant based on the surface area is reduced to propylene oxide 0.3 which is a low molecular surfactant. ０．５0.5% and 0.3-0.5% of sodium polycarboxylate which is a polymer surfactant. It is preferable that the mixing ratio is appropriately adjusted in consideration of the degree of dispersion in an aqueous solution, the degree of drying by a spray dryer, and the degree of clogging in carrying out. When these glaze raw materials are mixed, an appropriate surfactant is mixed with each according to the content, but the content of the glaze raw material is not limited. The color can be adjusted in the same manner as in the case of manufacturing a normal glaze, and any color adjustment can be performed in consideration of the color development after firing.

The slurry thus obtained is dried by a known ceramic spray dryer.
In particular, this spray dryer evaporates only the water content of the surfactant by directing the jet port after drying upward, and obtains a spherical powder having an average particle size of about 0.1 to 10 μm. The shape such as a sphere can be confirmed by an electron microscope. The surface-treated dried glaze raw material powder can be divided, packaged, and placed on a distribution channel. Even when stored in this way, the conventional particle surface becomes unstable and the particles do not undergo secondary aggregation in an aqueous solution due to a crosslinking reaction (silanolation reaction). The work of transporting lightweight bags with low moisture content is easy, and when used as glaze, this dry glaze raw material and other glaze raw materials that do not contain silicate groups are put directly into a stirring tank and stirred as simple as stirring. The step of re-grinding with a conventional ball mill in a short time is no longer necessary. In addition, since other glaze raw materials which do not contain a silicate group are not pulverized by a mill, it is desirable to purchase those having a particle size smaller than the conventional particle size. In addition, since it does not require the time to add and stir the pigment, color mixing can be easily performed at the porcelain factory even if it is not a glaze manufacturer, and the manufacture of glaze tailored to the production line equipped with roller hearth kiln In addition to this, the equipment for the ball mill is not required, and the work of cleaning the ball mill can be saved.

[0010] Since the surfactant has a bubble property when dissolved, an auxiliary agent such as a dispersant or an antifoaming agent is added to the glaze. Separately from the dry glaze raw material powder or mixed in the same bag, the dry glaze raw material powder may be put into water together when mixing and stirring, or it may be used for the glaze raw material before drying by spray drying. An agent may be mixed. In addition, ammonium salts, not sodium salts, must be used as raw materials for ceramic glaze for electronic components.

In addition, with the simplification of long-term storage and handling of dry glaze raw material powders, the control device controls each dry glaze stored for each basic color according to the design of ceramics and tiles made by image processing by CAD. The required amount is separated from the raw material powder, the mixture is poured into water, and the required amount of glaze is dissolved by stirring and the glazing can be applied to the ceramic or tile before firing in an automatic production line. Such equipment includes an automatic glaze manufacturing device that glazes ceramics and tiles before firing, a storage unit that stores dry glaze raw material powder and other glaze raw material powder, and a measuring unit that separates only the required amount. And a charging section for charging into water, a water tank section for dissolving the required amount of glaze only by mixing and stirring, and a cleaning section for carrying out the glaze and cleaning the inside, and the ceramics before firing by a known glaze section. There are devices for glazing and tiles. Also,
By providing a flow-down measuring unit at the lower end of the storage unit and also serving as the charging unit, by arranging a plurality of water tank units on the belt conveyor device and sequentially moving them to the lower position of the storage unit and the position of the washing unit, Glazes of different colors and shades can be automatically prepared and transferred to the glaze coating device. Further, it is also possible to electrostatically apply a pattern or the like to a ceramic or the like before firing by microencapsulation by converting the dried glaze raw material powder into a toner or enclosing the toner.

[0012]

As described above, according to the first aspect of the present invention, the average particle size of each glazing raw material powder having a silicate group is 0.1 to 10%.
Since it is a surface-treated dry glaze raw material powder that has been finely pulverized to μm and dried and adhered to a surface with at least a surfactant, it does not cause aggregation due to a cross-linking reaction as in the past.
It can be stored for a long time and transported lightly as it is. Just before using it as a glaze, mix it with a glaze raw material that has no silicate group.
The glaze could be prepared without the need for re-milling with a conventional ball mill, in addition to requiring only a short and simple operation of stirring. Further, in addition to the above effects, the invention according to claim 2 can produce a glaze of a different color by dissolving pigments and the like and mixing and stirring dry glaze raw material powders having different colors. Color mixing can be easily performed at the porcelain manufacturing site, making it possible to produce glaze that matches the production line equipped with roller hearth kilns, and eliminates the need for ball mill equipment, thereby saving labor such as cleaning. Was. Next, the invention according to claim 3 is directed to an automatic glaze manufacturing apparatus for glazing ceramics and tiles before firing, and separates a required amount from a storage unit for storing the dried glaze raw material powder according to claim 1 for each basic color. It is an automatic glaze manufacturing device that has a measuring section for taking water, a charging section for charging into water, and a water tank section for dissolving a required amount of glaze just by mixing and stirring, and glazing ceramics and tiles before firing. This allows the glaze to be prepared immediately before the amount required for the glaze, so that it can be installed in an automatic firing line that handles a large variety of small quantities, and there is no need to dispose of extra glaze as in the past.

Claims (3)

[Claims] Claims 1. A silicate-based glaze raw material is finely pulverized to an average particle size of 0.1 to 10 µm, and a surfactant is mixed with each aqueous solution and dried as fine powder.
A surface-treated dry glaze raw material powder characterized by having a surfactant adhered to its surface. 2. A method for producing a glaze, wherein the surface-treated dry glaze raw material powder and the other glaze raw material according to claim 1 are added to water and stirred to produce a glaze. 3. An automatic glaze manufacturing apparatus for glazing ceramics and tiles before firing, wherein a storage unit for storing the dry glaze raw material powder according to claim 1 and another glaze raw material, and a metering unit which separates only a required amount. Part, a charging part for charging into water, and a water tank part for dissolving a necessary amount of glaze just by mixing and stirring,
An automatic glaze manufacturing device equipped with a washing unit that takes out glaze and cleans the inside.