JPH03109248A - Production of ceramics - Google Patents

Abstract

PURPOSE:To reduce defective products by mixing ceramic material, a mixed emulsion of two kinds of anionic copolymers and an inorg. compd. in a specified ratio, forming the mixture into a ceramic material formed body, glazing, painting and calcining the body. CONSTITUTION:(A) One hundred pts.wt. of ceramic material powder, (B) 10-100 pts.wt., based on solid matter, of the mixed emulsion obtained by mixing the anionic copolymer aq. emulsion (B<1>) obtained by emulsion-polymerizing an unsaturated monomer mixture using an anionic surfactant for forming a multivalent metal ion and a chelate with the minimum film forming temp. (T<1>) fulfilling formula I and contg. 0-0.3wt.% carbonyl group and the anionic copolymer aq. emulsion (B<2>) fulfilling the film forming temp. (T<2>) in the solid weight ratio of A/B=(10-45)/(90-55) and 10-100 pts.wt. of an inorg. compd. forming multivalent metal ion in water are mixed at a temp. higher than T<1> and lower than T<2> to form a slurry. The slurry is filtered and dehydrated to obtain a water-contg. ceramic material which is dried and formed into a ceramic material formed body. The surface is glazed with a glaze aq. dispersion and dried. A pattern is transferred to the surface, and the body is calcined to obtain a painted ceramic.

Description

[Detailed Description of the Invention] (a) Purpose of the Invention (Field of Industrial Application) The present invention involves applying and firing a glaze without going through the bisque firing step, so that at least the firing of the green base material and the firing of the glaze are performed simultaneously. This invention relates to a method for manufacturing ceramics, or a method for manufacturing ceramics in which the raw material is fired, the glaze is fired, and the design is fired at the same time by applying a glaze without going through an unglazed firing process, transferring a design, and then firing it.

(Prior art) Traditionally, ceramics were manufactured by kneading green ceramic powder with water to make a slurry, and then molding green sheets from the slurry in an appropriate water-containing state or by blending aqueous resin emulsion with the slurry described above. After drying, the same sheet was molded by press molding, punching, etc. to obtain a green body molded body, and ceramics were manufactured from the green body molded body through the following steps.

Green body molded body → Unglazed (shime firing) – Glazed → Firing – Ceramic products In addition, to manufacture painted P [ware, after glazing the bisque fired (shime firing) molded body with an aqueous glaze dispersion, 100
After baking at a temperature of 0 to 1,400°C, the pattern layer formed on the transfer paper is transferred onto it, and further baking is performed at a temperature of 500 to 1,400°C to cause the synthetic resin contained in the pattern layer to decompose and fail. They removed them and obtained painted ceramics.

The reason why the green green molded body is once bisque fired in this manner is that if the glaze is directly applied to the surface of the green green body molded body and fired, cracks, chips, etc. will occur in the green body during firing.

The conventional method of manufacturing the above-mentioned painted ceramics requires two firing processes in addition to unglazed firing: firing the glaze and firing the pattern layer, which is complicated, has low thermal efficiency, and is economically disadvantageous. There was a drawback. As a method to improve this, a glaze is applied to the bisque fired surface of the green body molded body, and then a primer mainly composed of a synthetic resin emulsion, an aqueous solution of a water-soluble polymer, or a mixture thereof is applied to the surface of the glaze layer. Next, a method was proposed in which a pattern for transfer is transferred onto the layer, brought into close contact, and then fired, thereby simultaneously firing the glaze and the pattern layer (Japanese Patent Publication No. 45073/1983). Although this method allows one firing step to be omitted, the number of primer application steps is increased, and since a primer containing a large amount of water is applied onto the glaze layer, there is a risk of damaging the glaze layer.

In addition, there is a method of painting directly on the glaze layer before firing.
It has the disadvantage of weakening the adhesion between the glaze layer and the pattern, and in order to improve this, improved methods have been proposed such as mixing a resin binder into the raw f+b agent or applying a brimer on the glaze layer. However, these methods also have problems with the adhesion between the glaze layer and the pattern layer (
The problem was that the defect rate was high due to insufficient adhesion (adhesion) and the occurrence of floating patterns, pinholes, shrinkage, etc. during pre-drying. Furthermore, the method of mixing a resin binder into the raw glaze has a problem in that the glaze composition mixed with the resin binder has poor storage stability.

In order to improve these drawbacks of the conventional method, the present inventors first added 1.4X of carboxyl groups (-C0011) based on α,β unsaturated carboxylic acids to ceramic green molded bodies.
A glaze composition containing an anionic copolymer resin emulsion containing an anionic copolymer resin emulsion in a proportion of 10-' to 1.8 x 10-' moles is applied, the glaze layer is dried and solidified, and then a pattern for transfer is formed by a water slide method. proposed a method in which the glaze composition and the pattern are fired at the same time by transferring, or by overcoating a glaze composition on the transfer layer, followed by firing (Japanese Patent Application Laid-Open No. 100094/1983). Publication No.),
However, this method has the disadvantage that it is not easy to apply the glaze composition to the green molded body, and in order to improve this, a large amount of the glaze composition containing an aqueous emulsion of anionic copolymer resin is used. When diluted with water and applied with glaze, the adhesion between the raw material and the glaze decreases, resulting in a decrease in the water resistance of the glaze.

(Problems to be solved by the invention) The present invention allows at least the firing of the green molded body and the firing of the glaze layer to be performed at the same time, to reduce the occurrence of defects such as damage to the base, and to improve the adhesion between the base and the glaze. The purpose of this invention is to provide a method for manufacturing ceramics that allows excellent ceramic products to be easily obtained.

In addition, the present invention allows the firing of the green body molded body, the firing of the glaze layer, and the firing of the pattern layer to be performed simultaneously, thereby reducing the occurrence of defects such as damage to the base, and in addition, the firing of the green body, the glaze layer, and the pattern layer. The purpose of the present invention is to provide a method for manufacturing ceramics that can easily produce ceramic products that have excellent adhesion to surfaces.

(bl Structure of the invention (means for solving the problem) The present inventors have developed various methods (σE
As a result of repeated research, we have arrived at the present invention.

The first method for producing ceramics of the present invention includes: (8) 100 parts by weight of ceramic base powder; (13) an unsaturated monomer mixture using an anionic surfactant that forms a chelate compound with polyvalent metal ions; The minimum film forming temperature or glass transition temperature (T) obtained by emulsion polymerization satisfies the following formula (1), and the carboxyl group content is θ
An aqueous emulsion of a copolymer with a solid content of 0.6 to 2.5% by weight of the anionic surfactant based on the copolymer. Film-forming temperature (T2) obtained by emulsion polymerization of an unsaturated monomer mixture using an anionic copolymer aqueous emulsion (B1) and an anionic surfactant that forms a chelate compound with a polyvalent metal ion. ) satisfies the following formula (11) and has a carboxyl group content of 0 to 0.3% by weight, wherein the anionic surfactant is The solid content ratio is 0.
A mixed emulsion with an anionic copolymer aqueous emulsion (B2) containing 6 to 2.5% by weight,
Copolymerizing the copolymer aqueous emulsion (B1)/the copolymer aqueous emulsion (the mixed emulsion in which the mixing ratio of B is (10 to 45)/(90 to 55) in terms of copolymer solid content weight ratio 10 to 50 parts by weight of the combined solid content,
and (C) Inorganic compound 10 that generates polyvalent metal ions in water
~100 parts by weight of the aqueous copolymer emulsion (B1) at a temperature higher than the lowest film forming temperature or glass transition temperature (T1) of the copolymer of the aqueous copolymer emulsion (B1).
Mixing the B-based copolymer at a temperature lower than the minimum film forming temperature (T2) to form a slurry, and filtering and dehydrating the resulting slurry under the above temperature conditions to obtain a hydrous ceramic green base;
The obtained hydrated green body is molded to form a ceramic molded body, and then dried at a temperature exceeding the minimum film-forming temperature (T) of the copolymer of the copolymer aqueous emulsion, or the above-mentioned hydrated ceramic green body is The dried product of the copolymer aqueous emulsion (B2) is molded by heating and pressure molding at a temperature exceeding the minimum film-forming temperature of the copolymer (B2), and then the obtained A glaze aqueous dispersion containing a glaze and an anionic resin aqueous emulsion is applied onto the surface of a dry ceramic green body molded body, and then fired, so that at least the green body and the glaze are fired at the same time. This method is characterized by the following.

Formula (I): (Mud temperature - 45℃) <7"< (Mud temperature)
... (1) In formula (r), T1 is a copolymer emulsion (B1
), or when the minimum film-forming temperature of the same copolymer is below the freezing temperature of mud, it is the glass transition temperature of the copolymer.

Formula (■); (Mud temperature) < Tz −, -----・-(II
) In formula (T1), T2 is the lowest film forming temperature of the copolymer of the copolymer aqueous emulsion (B2).

In addition, in the second method for manufacturing ceramic utensils of the present invention, after drying and solidifying the glaze aqueous dispersion layer after glazing in the first method for manufacturing ceramics, The pattern for transfer is transferred by a method, or the above-mentioned aqueous glaze dispersion is coated again on the transfer surface of the pattern, and then fired to simultaneously perform firing of the green base, firing of the glaze, and firing of the design. This is a method to

The ceramic base powder (i.e., china clay) of component (A) in the present invention is not essentially different from china clay used in conventional ceramic manufacturing, and even if it is
It is prepared by appropriately blending kaolin, clay, feldspar, mica, bentonite, talc, silica stone, etc. whose main component is 1 t03. In addition, fired ceramics [pulverized products of H or AN
,0. So-called new ceramic raw materials such as these can also be used.

The anionic copolymer aqueous emulsion as component (B) in the present invention is obtained by emulsion polymerization of an unsaturated monomer mixture using an anionic surfactant that forms a chelate compound with a polyvalent metal ion. An aqueous emulsion of a copolymer whose minimum film-forming temperature or glass transition temperature (T1) satisfies the above formula (1) and whose carboxyl group content is 0 to 0.3% by weight, and in which the anion The solid content ratio of the surfactant to the copolymer is 0.
Emulsion polymerization of an unsaturated monomer mixture using an anionic copolymer aqueous emulsion (B1) containing 6 to 2.5% by weight and an anionic surfactant that forms a chelate compound with a polyvalent metal ion. An aqueous emulsion of a copolymer whose film-forming temperature (T) obtained by Anionic copolymer aqueous emulsion (B2) containing a surfactant in a solid content ratio of 0.6 to 2.5% by weight based on the copolymer
), and the copolymer aqueous emulsion (B1)/the copolymer aqueous emulsion (B1).
The mixing ratio of B2) is copolymer solid content weight ratio (10 to 4
5)/(90-55).

Examples of unsaturated monomers used to produce the anionic copolymer aqueous emulsion (B1) and (B) include acrylic acid alkyl esters and methacrylic acid alkyl esters (the carbon atoms of the alkyl groups of these alkyl esters). Numbers are 1 to 8), 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-
Hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, acrylamide, methacrylamide, methylolacrylamide, vinyl chloride, vinylidene chloride, ethylene, acrylonitrile, vinyl acetate, styrene, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, crotonic acid, maleic anhydride Examples include acids, sodium vinyl sulfonate, etc.

The anionic copolymer aqueous emulsions (B1) and (B2) used in the present invention are produced by appropriately selecting and copolymerizing two or more of these unsaturated 41-mers. The combination h1 of unsaturated carboxylic acids shall be such that the degree of carboxyl u'lfa in the resulting copolymer is within the range of 0 to 0.3% by weight in both aqueous emulsions (B1) and (B2). .

In addition, the unsaturated monomers are selected and used in combination so that the minimum film forming temperature or glass transition temperature (T1) of the copolymer in the aqueous emulsion (B1) can satisfy the above formula (1). , and are selected so that the minimum film forming temperature (T2) of the copolymer of the aqueous emulsion (B2) can satisfy the above formula (I1).

In addition, the anionic copolymer aqueous emulsion of the present invention (
Examples of anionic surfactants that form chelate compounds with polyvalent metal ions used in the production of B1) and (B2) include fatty acid sodas (soda soaps) such as sodium laurate and sodium stearate; Sodium organic sulfonates such as ethylene alkyl ether sulfate ester soda, polyoxyethylene alkylphenyl ether sulfonate sodium, alkanesulfonate sodium, alkylbenzene sulfonate sodium, alkyldiphenyl-terdisulfonate sodium, fatty acid sarcosides, rosin acid sodium, etc. Potassium salts, ammonium salts, alkanolamine salts, etc. may be used instead of the various soda salts mentioned above.

Other surfactants (
Emulsifiers), for example nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylenized castor oil, etc., can be used together in relatively small amounts. Use of a small amount of these nonionic surfactants is effective for stabilizing polymerization.

Examples of inorganic compounds that generate polyvalent metal ions in water as component (C) in the present invention include oxides, hydroxides, sulfates, and carbonates of polyvalent metals such as calcium, magnesium, iron, aluminum, and strontium. Examples include salt. Examples of such devices include inorganic compounds that dissolve in water to generate polyvalent metal ions, preferably inorganic compounds that dissolve in water little by little to slowly generate polyvalent metal ions, such as gypsum, quicklime, magnesium oxide, Examples include magnesium carbonate, strontium carbonate, etc. Among these, calcium compounds and magnesium compounds are preferred in terms of solubility and reaction rate with anionic surfactants.

In the present invention, copolymer aqueous emulsion ([31
) or the glass transition temperature of the copolymer (
Component (A), component (B) and component (C) are mixed at a temperature higher than T1) and lower than the minimum film-forming temperature of the copolymer aqueous emulsion (800m). The slurry is then filtered and dehydrated under the above-mentioned temperature conditions using a method such as a filter press method or a papermaking method to obtain a hydrated ceramic base.

Generally, in the production of Il&J porcelain, water is added to ceramic base powder to form a milk-like product with a water content of 50 to 60% by weight.
The so-called mud is filtered and dehydrated using a filter press or papermaking, and the resulting water content is 20 to 30.
% by weight of a ceramic green body is molded and dried to obtain a dry green ceramic body molded body, but the drying process takes several days and the work is not efficient.

In order to carry out this drying process in a short time, attempts have been made to heat and press-form the dried green ceramic material at 100 to 180°C, but the strength of the resulting dry molded product is low, and it may be chipped or It has drawbacks such as cracking and tearing, poor workability, and large shrinkage of dried material, and is therefore impractical.

In the present invention, as described above, a ceramic base powder is used as the (A) component, a mixed emulsion obtained by mixing two types of anionic copolymer aqueous emulsion (B1) and (BQ) as the (B) component, and (C Component (C) is mixed with an inorganic compound that generates polyvalent metal ions in water to make a slurry. At that time, component (C) dissolves in water and the polyvalent metal ions generated dissolve in the component (B). It acts on the anionic surfactant contained in the emulsion to form a chelate compound, deactivating the surfactant and destroying the emulsion. ) The particles will adhere to the ceramic base powder of component (A).

By the way, in the present invention, a mixed emulsion of two types of anionic copolymer aqueous emulsions (B1) and (B2) is used as the copolymer emulsion as component (B), and the present invention The slurry in the invention is prepared at a temperature higher than the lowest film forming temperature or glass transition temperature (T1) of the copolymer of the copolymer emulsion (B1), and the slurry of the copolymer emulsion (B2)
At a temperature (usually 0 to 40°C) lower than the lowest film forming temperature (T2) of the copolymer, the above components (A) to (C)
Since the mixing is performed, the prepared slurry does not cause the base powders to stick to each other depending on the copolymer derived from the emulsion (B2). Moreover, the mixing ratio of copolymer emulsion (B1)/(B2) is (10-45)/(90-55) in solid content of copolymer, and the copolymer derived from emulsion (B2) is The amount of copolymer derived from emulsion (B1) is larger than that of the copolymer derived from emulsion (B1).

Therefore, in the present invention, the slurry prepared by mixing components (A) to (C) with an appropriate amount of water under the above-mentioned temperature conditions has copolymers (B1) and (B2) added to the base powder. Even if the derived copolymer is attached, it will not coagulate into large lumps as a whole, and the particle size will be moderate (for example, number + 8 or more), so it will not clog filter cloth etc. It can be easily filtered and dehydrated using a filter press or paper making without causing any problems. It goes without saying that during the filtration and dewatering of this slurry, the same temperature conditions as those used during the slurry preparation described above are used. Furthermore, in the present invention, the filtration and dehydration using the filter press, paper making, etc. described above are carried out after the copolymer emulsion is destroyed by the component (C) and the copolymer is aggregated, so the slurry is prepared. Works such as filtration and dehydration of water can now be carried out by using a large amount of water to lower the viscosity, and the effect can be obtained that these works can be carried out efficiently.

Note that, instead of the method of the present invention, if the copolymer emulsion is prepared using a surfactant other than an anionic surfactant that forms a chelate compound with a polyvalent metal ion, or Even when prepared with anionic surfactants forming compounds,
If component (C) is not mixed, the copolymer emulsion will not be destroyed during the preparation of the slurry, so the resulting slurry will not contain the copolymer of the emulsion during filtration and dehydration using a filter press or papermaking. Particles (particle size 0.0
(5 to 3 microns) may clog the filter cloth, etc., or the same particles may ooze out onto the surface of the filter cloth and form a dry film on that surface, facilitating filtration and dewatering. I can't.

In addition, if the copolymer emulsion (B1) or copolymer (B2) contains too many carboxyl groups, polyvalent metal ions generated from the component (C) will be absorbed into the carboxyl group during the preparation of the slurry. consumed by the group,
Breaking the copolymer emulsion and agglomerating the copolymer particles,
It takes a long time to solidify and solidify, which in turn increases the working time. Therefore, in the present invention, the copolymer emulsion (B1) and the copolymer (B) have carboxyl group-containing M
The content should be 0 to 0.3% by weight.

Moreover, the copolymer copolymer emulsion (B1) of the present invention
and (B2) should each be contained in an amount of 0.6 to 2.5% by weight based on the anionic surfactant to copolymer. This is because if the proportion of anionic surfactant is too high,
During the preparation of slurry, the emulsion cannot be broken sufficiently by component (C). In other words, if the proportion of anionic surfactant exceeds 2.5% by weight, it will take a long time for the copolymer particles to coagulate and coagulate due to the destruction of the emulsion during slurry preparation, and depending on the constituent components of the copolymer, When the prepared slurry is allowed to stand, a portion of the copolymer emulsion separates onto the precipitated hydrous ceramic green base layer. Since the copolymer particles contained in the emulsion that separates into the -L layer are approximately 0.03 to 3 microns in size, the copolymer particles are removed during filtration and dehydration using a filter press, etc. It may clog the filter cloth, or it may ooze out onto the surface of the filter cloth and dry to form a film, interfering with smooth filtration and dewatering.

On the other hand, if the proportion of anionic surfactant is too small, the polymerization stability during the preparation of the copolymer emulsion may deteriorate, the storage stability of the resulting copolymer emulsion may become poor, or even muddy. This is because during the preparation of the powder, the copolymer emulsion breaks down quickly, which prevents the agglomerated copolymer particles from uniformly adhering to the base powder.

In addition, in the present invention, a copolymer emulsion (B1
)/copolymer emulsion (B2) is set to (10-45)/(90-55) in copolymer solid content weight ratio. This is because if the amount of copolymer in the copolymer emulsion (B1) becomes too large, the copolymer particles that aggregate and precipitate during slurry preparation are
), and this copolymer exhibits stickiness at the temperatures during slurry preparation, filtration, and dehydration, causing the slurry to solidify into large clumps and even cause The coagulated lumps stick to filter cloth, etc., making it difficult to filter and dehydrate the slurry. And vice versa,
If the amount of copolymer in the copolymer emulsion (B1) is too small, the green molded product obtained by molding the dehydrated slurry after filtration or papermaking will have poor strength and water resistance before drying. Because it becomes.

The blending ratio of component (A), component (B), and component (C) during the preparation of slurry in the present invention is such that component (B) is the copolymer solid content relative to 100 parts by weight of component (Δ). 1
0 to 50 parts by weight, and component (C) 10 to 100 parts by weight. (B) If the amount of the component is too small, the strength of the ceramic green molded body will be weakened and the molded body will be more likely to chip or crack. (C) A large amount of ingredients is required, and the failure of the emulsion to break down is insufficient, which impedes the filtration and dehydration work of slurry.Furthermore, the number of combustion component meters required during the ceramic firing process increases. It also causes a decrease in the strength of the product. In addition, component (C) is used in an amount necessary to break the emulsion of component (+3) and within a range that does not impair the necessary physical properties of the resulting ceramic green base. The amount is 10 to 1 per 100 parts by weight of component (A).
00 parts by weight, and preferably 0.5 to 2.5 times the emulsion amount of component (B).

The preparation of the slurry of the present invention involves crushing ceramic base powder,
In order to sufficiently and uniformly mix the components (A), (B), and (C), a pulverizer such as a ball mill can be used.

Additionally, a large amount of water can be added to facilitate the transport, filtration, and dewatering of the mixed slurry. Furthermore, colorants, dispersants, wetting agents, water reducing agents, etc. can be added as necessary.

Next, in the present invention, the slurry prepared as described above and in which the copolymer emulsion has been destroyed by component (C) is filtered and dehydrated by a filter press method or a papermaking method to obtain a hydrated ceramic material. Make it a base material. The slurry temperature during filtration and dehydration is the same as that during slurry preparation, that is, the copolymer emulsion (B
The temperature is maintained at a temperature higher than the minimum film-forming temperature or glass transition temperature (T1) of the copolymer (1) and lower than the minimum film-forming temperature of the copolymer emulsion (B2).

This is to facilitate the filtration of the slurry for the same reason as when preparing the slurry.

Next, in the present invention, the hydrated green body obtained by filtration and dehydration is formed into a hydrated ceramic green body molded body,
The water-containing molded body is dried at a temperature exceeding the copolymer emulsion (the lowest film forming temperature (T2) of the B copolymers, or
Alternatively, the dried green material obtained by drying the water-containing green material obtained as described above is heated at a temperature exceeding the minimum film forming temperature (T2) of the copolymer of the copolymer aqueous emulsion (B2). A dry l1hJ C1l green body molded body is prepared using any of the following methods.

Forming of the wet green material can be carried out by using potter's wheel method, extrusion molding method, cast molding method, room temperature press molding method, etc. using the moderately water-containing ceramic green material obtained by filtering and dehydrating. Alternatively, it can be formed by press forming, punching, etc. from a hydrous green base sheet obtained by filtration or papermaking.

For molding the dried green material, a heating and pressure molding method using the above-described temperature conditions is used.

The molded body obtained by molding two pairs of hydrated green bodies is based on the adhesive strength (tackiness) of the copolymer derived from the copolymer emulsion (B1) and the plasticity of the ceramic base powder itself. It has appropriate initial strength and water resistance, and prevents the molded product from warping or breaking before drying. In addition, when the water-containing molded body is dried at a temperature exceeding the minimum film forming temperature of the copolymer of the copolymer emulsion (B2) by heating with hot air, far infrared rays, high frequency, etc.
The obtained dried molded body has adhesive strength (fusion strength) of the copolymer whose base particles are derived from the copolymer emulsion (B2).
As a result, the strength and water resistance of the dried molded product are further improved.

Furthermore, a dried molded product obtained by heat-pressing molding the dried green material under the above-mentioned temperature conditions also has excellent strength and water resistance for the same reason.

Next, in the present invention, a glaze aqueous dispersion containing a glaze and an anionic resin aqueous emulsion is applied onto the surface of the dried ceramic green body molded body obtained as described above. The aqueous glaze dispersion is preferably one in which 100 parts by weight of the glaze is mixed with 4 to 20 parts by weight of anionic resin aqueous emulsion as a resin solid content.

The glazes are transparent glaze, colored glaze, crystal axis, lead glaze, flint glaze, bristol glaze, according to component classification.
Alternatively, any of the various glazes referred to as porcelain glazes, porcelain glazes, etc. depending on the usage classification can be used.

As an example, the composition of 5K13 porcelain glaze is as follows.

Feldspar 73.57% by weight Magnesite 5.35 Lime ash
Stone 0.87 Kao
Rin 5.68 〃
Quartz 14.53 Total 100% by weight Also,
A preferred aqueous anionic resin emulsion used for preparing the aqueous glaze dispersion includes 100 parts by weight of an unsaturated monomer mixture having the following composition, and 0.1 to 0.1 to 0.1 to an anionic emulsifier.
This is a copolymer resin emulsion prepared by emulsion polymerization in the presence of 5 parts by weight and 0 to 5 parts by weight of a nonionic emulsifier.

(a) Hydroxyl group-containing unsaturated monomer 0.3-10% by weight) Acrylic acid alkyl ester (alkyl group has 2-8 carbon atoms) (40-55 monomer selected from C1 methyl methacrylate and acrylonitrile) Body 30-55% by weight (d)
Okimer selected from N-phenylmaleimide, N-methylolacrylamide, acrylamide and methacrylamide 1 to 1O〃(el) Other monomers 0 to 20 The above (a) monomers include 2- Hydroxyedyl acrylate, 2-
Acrylates such as hydroxypropyl acrylate, pentaerythritol tetraacrylate, diethylene glycol monoacrylate, and their methacrylate-1
・, allyl alcohol, etc. In terms of storage, dispersibility, adhesion, water resistance, etc., these
It is used in an amount of 0.3 to 10% by weight based on the monomer mixture.

In addition, (acrylic alkyl ester of bl monomer is a rough 1-monomer that gives flexibility to the film, and includes ethyl acrylate, isopropyl acrylate, n-butyl acrylate, acrylic Mt-butyl, acrylic Pan- Examples include propyl, 2-ethylhexyl acrylate, and the like.

In addition, (C1 monomer is a hard monomer that gives toughness to the skin. A part of this monomer can be replaced with ethyl methacrylate, isopropyl methacrylate, or isobutyl methacrylate.

Furthermore, the monomer (d) is used to impart adhesiveness and dispersibility to the ceramic base powder.

Examples of the (e) 4L-mer include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and maleic anhydride, styrene, ethylene, butadiene, and the like. In the case of the unsaturated carboxylic acid, the amount used is such that the proportion in the copolymer is 8X10-3 to 8XlO-' mole or less.

The copolymer emulsions (I31) and (B2) used for the component (B) in the present invention, and mixtures thereof, can also be used as the anionic resin aqueous emulsion for the glaze aqueous dispersion of the present invention. .

The aqueous anionic resin emulsion for the aqueous glaze dispersion of the present invention has a minimum film forming temperature of 10% from the viewpoint of good film formation of the glaze layer, hardness of the film, prevention of stains due to stickiness of the film, etc. An emulsion of the resin at a temperature of 0.degree. C. or above is preferred.

In addition, this anionic resin aqueous emulsion contains 0% water-soluble birophosphate and/or tripolyphosphate per 100 parts by weight of the resin solid content of the emulsion in order to prevent viscosity increase and gelation during mixing of the glaze. It is desirable to contain it in a proportion of .05 to 5 parts by weight. It is desirable that each of these phosphates be added to the polymerization system during emulsion polymerization to produce an aqueous anionic resin emulsion for emulsion polymerization, but they may be added to the emulsion after polymerization. Specific examples of the phosphate include sodium salt, potassium salt, and animonium salt of pyrophosphoric acid or tripolyphosphoric acid.

When a pattern is transferred to the anion layer added to the aqueous glaze dispersion of the present invention by a water slide method or when the glaze is overcoated on the transferred pattern layer, the emulsion particles prevent the glaze layer from collapsing. Controlling the penetration of glaze components into the raw material, improving the strength of the glaze layer with an emulsion resin film, protecting the glaze layer by preventing scratches and peeling of the glaze surface during movement of the glazed molded object and during work, and protection of the glaze layer. This provides various effects such as improved adhesion with the pattern layer.

Various methods can be used to prepare the aqueous glaze dispersion of the present invention. A typical preparation method is to add an appropriate amount of water and a dispersant to 100 parts by weight of the glaze, mix in a ball mill, then add 4 to 20 parts by weight (resin solid content) of an anionic resin aqueous emulsion, and then add anionic resin. If the aqueous resin emulsion does not contain pyrophosphate or tripolyphosphate, 0.05 to 5% by weight of birophosphate or tripolyphosphate is added to the resin solid content, and further quenched as necessary. Foaming agents, dispersants, etc. are added and mixed to form an aqueous glaze dispersion having a water content of 25 to 65% by weight.

Glazing in the present invention is carried out by applying the aqueous glaze dispersion onto the surface of the dry ceramic green molded body obtained as described above.

Methods for applying the glaze include spraying, dipping, and pouring, and when glazed using these methods, a raw glaze layer is formed on the surface of the green body molded product.

If the raw glaze layer after glazing is dried and solidified and then fired without decoration, the raw base material and the glaze are fired at the same time, resulting in glazed ceramics. In addition, after drying and solidifying the raw glaze layer, painting is done using an appropriate method, and if necessary, glazing is applied again on the patterned surface, and the raw glaze layer is dried and solidified before firing. The firing of the base, firing of the glaze, and firing of the Σ pattern are performed simultaneously to obtain the desired painted ceramics.

A particularly preferred method for painting in the present invention is to dry and solidify the raw glaze layer after glazing, and then transfer a pattern for transfer onto it by a water slide method, or to apply the above-mentioned glaze again onto the transfer surface of the pattern. This is a method of overcoating aqueous dispersions.

The transfer paper used in this case has a water-soluble polymer coated on the surface of the paper, a pattern layer is formed on top of the paper with a pattern printed with ink made of synthetic resin and pigment, and then reinforced with synthetic resin. It has layers. When such a transfer paper is immersed in water, the water-soluble polymer dissolves and the pattern layer is peeled off from the paper together with the reinforcing layer, which is then transferred onto the dried and solidified glaze layer. This method is generally called the water slide method. At that time, the pattern layer will be transferred onto the surface of the glaze layer with a large amount of moisture attached, but since the resin component of the synthetic resin emulsion provides water resistance, the glaze layer will be able to resist the collapse. It can definitely be prevented.

This effect can be similarly obtained when the pattern layer is applied directly onto the glaze layer instead of transferring the pattern using the water slide method. In addition, as the synthetic resin for reinforcing the pigment of the above-mentioned transfer paper for decoration, an aqueous anionic resin emulsion similar to that mixed in the above-mentioned aqueous glaze dispersion can be used.

After painting, firing is done by drawing lines or adding patterns as necessary to give the ceramic a beautiful finish, and then firing it at a temperature higher than the melting temperature of the glaze. During firing, all the resin and surfactant in the emulsion are decomposed and volatilized, and the firing of the raw material, glaze, and design are performed simultaneously, producing painted ceramics.

(Examples etc.) Below, anionic copolymer emulsion production examples, examples, and comparative examples are given and further explained in detail.

In addition, the parts and percentages mentioned in these examples mean parts by weight and percentages by weight unless otherwise specified.

Anionic copolymer emulsion production example 1 temperature controller,
A reaction vessel equipped with an anchor type stirrer, a reflux condenser, a feed vessel, a thermometer and a nitrogen inlet tube was charged with the following mixture of water and emulsifier.

water 200
Part 30% aqueous solution of the sodium salt of the sulfuric acid half ester of p-nonylphenol (anionic emulsifier) reacted with 20 moles of ethylene oxide; Then, after replacing the inside of the reaction vessel with nitrogen gas, 10% of Feed I shown below was added and heated to 90°C.

Supply ■: Water 20
0 parts 30% aqueous solution of the above anionic emulsifier 25 parts Methyl methacrylate 195 parts n-butyl acrylate 189 parts 2-hydroxypropyl acrylate 8 parts Acrylamide 8 parts Additionally, 8 parts
2.5 parts of potassium persulfate dissolved in 5 parts of water (
After charging 10% of the feed material (■) into the reaction vessel, the rest of the feed material (■) and the rest of the feed material (■) were fed into the reaction vessel over a period of 3.5 hours, and after the feeding was completed, the remaining part of the feed material (■) was fed into the reaction vessel for 2 hours. Feed I was polymerized at 90° C. to obtain an anionic copolymer aqueous emulsion.

Anionic Copolymer Emulsion Preparation Example 2 Into a reaction vessel similar to that in Preparation Example 1, a mixture of water and emulsifier similar to that used in Preparation Example 1 was fed.

Next, after purging the inside of the reaction vessel with nitrogen gas, 10% of the feed I shown below was added, and the mixture was heated to 90°C.

Supply ■: Water 200
30% aqueous solution of the anionic emulsifier used in Production Example 1 25 parts acrylic acid 2 parts methyl methacrylate 195 parts n-butyl acrylate
195 parts acrylamide
In addition, 1.25 parts of potassium persulfate and 1 part of sodium birophosphate were dissolved in 42.5 parts of water. All the remaining parts and all the remaining part of Feed H were fed into the container over 3.5 hours, and after the feeding was finished, the feed I was polymerized by keeping it at 90°C for 2 hours to obtain an anionic copolymer aqueous emulsion. Ta.

Anionic copolymer emulsion production examples 3 to 12 Various copolymers were prepared according to Production Example 1 above, except that the type and amount of the unsaturated monomer and the type and amount of the emulsifier were changed as shown in Table 1. An aqueous emulsion was prepared.

The physical properties of the anionic copolymer emulsion obtained in each of the above production examples were as shown in Table 1.

Notes to Table 1: *1...Kao Soap Company product name Emar NC-35*2
... Kao Soap Co., Ltd. trade name LATEMUL PS, sodium alkane sulfonate *3 ... Alkyldiphenyl ether disulfonic acid *5 ... The amount of emulsifier used is parts by weight based on 100 parts by weight of the copolymer.

Example 1 60 parts of feldspar, 470 parts of chinastone, 100 parts of silica, 2 parts of frog's eye clay
After adding 1,500 parts of water to 1,000 parts of china clay consisting of 0.0 parts and 170 parts of Kibushi clay, the mixture was heated in a ball mill at 20°C.
The slurry was pulverized for 20 minutes at a temperature of Polymer emulsion (minimum film forming temperature 43
C) and 250 parts of β-gypsum were added and further ground for 1 hour in a ball mill to obtain a slurry of china clay particles to which copolymer particles were attached. Even when this slurry was allowed to stand, no separation of the copolymer emulsicon was observed.

This slurry was vacuum filtered at 25° C. under a reduced pressure of 500+ mHg to obtain a green ceramic base having a water content of about 20%. There was no clogging of the filter cloth during filtration of the slurry.

Next, this raw material was dried at 30℃ or less,
Place in press mold, 100℃, pressure 20kg/cs
150wm x 1 with a thickness of 51 mm.
A 50 am plate-shaped green body molded body was obtained. This material was hard, had no cracks or chips, and had little shrinkage.

Next, 100 parts of water was added to 100 parts of commercially available self-shaft and pulverized in a ball mill (approx. 58% solids, pH 9.3). To 100 parts by weight of this dispersed glaze solution was added the anionic resin emulsion obtained in Production Example 3 ( A glaze aqueous dispersion was obtained by blending 10 parts of glaze (minimum film forming temperature: 43° C.). Even when this aqueous glaze dispersion was allowed to stand at room temperature for 24 hours, neither thickening nor formation of aggregates was observed.

Next, the aqueous glaze dispersion was sprayed onto the surface of the green molded body, pre-dried at 150°C, and then
After transferring the pattern layer printed on the transfer paper onto the surface of the glaze layer using the water slide method, the painted molded body was
Fired at 50°C (glaze firing) to obtain a ceramic plate with a clear pattern. This ceramic board was highly strong, with no chips or cracks.

Comparative Example 1 The temperature of the filtrate during filtration in Example 1 was changed to the lowest film forming temperature (43°C) of the emulsion copolymer obtained in Production Example 3.
) When the temperature was set to 55°C, which is higher than the above temperature, the raw ceramic powders fused together and formed a lump. In addition, the slurry obtained in Example 1 was gradually heated to 55%
When the temperature was raised to 45°C, thickening was observed from about 45°C.

Example 2 When Ca5Oa, MgO or MgCO3 was used in place of the emulsion breaking agent β-gypsum used in Example 1, no clogging of the filter cloth occurred during filtration of slurry.

Examples 3 to 5 Comparative Examples 2 to 3 The total blending amount of the copolymer emulsion and the blending amount of β-gypsum with respect to 1000 parts of ceramic base powder in Example 1 were changed as shown in Table 2, and the other changes were carried out. Example 1
A green body molded body for a chest plate was produced in the same manner as above. The results were as shown in Table 2.

Example 6 75 parts of the copolymer emulsion obtained in Production Example 4 (minimum film forming temperature 19°C) and 75 parts of the copolymer emulsion obtained in Production Example 6 (minimum film forming temperature 275 parts of the mixture (temperature: 63°C) were added, water was further added, and the mixture was ground in a ball mill for 20 hours.

Next, 300 parts of Mg was added thereto, and the mixture was further mixed and ground in a ball mill at 30°C, and then filtered at 30°C using a filter press to obtain a hydrous green material with a water content of about 22%. Next, this water-containing green material is subjected to a pressure of 20 kg/
cm”, and the molded product was further heated to 8 cm.
By heating and drying at 0° C., the copolymer derived from the emulsion obtained in Production Example 6 was formed into a film, and a dry, strong alternating base molded body was obtained.

Next, 150 parts of water was added to 100 parts of a commercially available frit glaze, and after crushing with a ball mill, 20 parts of the copolymer emulsion obtained in Production Example 8 (min. An aqueous glaze dispersion was obtained.

This glaze dispersion was sprayed onto the surface of the dried alternating base molded body, dried at 120°C, and then heated to 900°C.
The tiles were fired at ℃ and had no cracks.

Example 7 Instead of 300 parts of Mg0 in Example 6, Mg010
A crack-free roof tile was obtained in the same manner as in Example 6 except that a mixture of 0 parts of β-gypsum and 200 parts of β-gypsum was used.

Examples 8 to 12 Comparative Examples 4 to 16 Ceramic green molded bodies were produced in accordance with Example 1 except that the slurry compositions shown in Table 3 were used and the pressure molding temperatures shown in Table 3 were used.

Next, a glaze aqueous dispersion having the composition shown in Table 3 was applied to the surface of the green molded body, and after drying the glaze layer, Example 1
It was painted in the same manner as above and fired in the same manner. The physical properties of the obtained ceramic were as shown in Table 3.

The stability of the aqueous glaze dispersion shown in Table 3 was measured and evaluated by the following method.

Storage stability was evaluated by keeping the glaze aqueous dispersion (glaze→-copolymer emulsion) at 50"C for 30 days, and then returning the temperature to 20°C, and evaluating the state of the liquid using the following criteria.

○...No change. Viscosity 500cps or less. Contains no whelk.

×...Gelification. The system solidifies and does not return to its original state even after stirring.

Freeze stability is evaluated based on the criteria below after adding the copolymer emulsion to the glaze, putting it in a container, sealing it, keeping it at -5℃ for 20 hours, and then returning it to room temperature for 3 hours. did.

○...No change.

×...Agglomerated.

Notes to Table 3: *l...During papermaking, the copolymer lacks adhesive strength and is chipped. In addition, even during pressure molding at 100°C, its strength is low and it is easily chipped.

(C1 Effects of the Invention In the present invention, an excellent green ceramic body can be efficiently produced, a molded body of the obtained green body is glazed without going through the bisque firing process, and the firing of the green body and the firing of the glaze are performed separately. do it at the same time,
Alternatively, firing the green base, firing the glaze, and firing the pattern can be performed at the same time to significantly reduce the occurrence of defective products such as damage to the base, poor adhesion between the base and glaze layer, and poor adhesion between the base, glaze layer, and pattern layer. As a result, excellent ceramic products can be advantageously manufactured with improved efficiency such as thermal efficiency.

Claims (1)

[Claims] (1) (A) 100 parts by weight of ceramic base powder; (B) Emulsion polymerization of an unsaturated monomer mixture using an anionic surfactant that forms a chelate compound with polyvalent metal ions. An aqueous emulsion of a copolymer whose minimum film-forming temperature or glass transition temperature (T^1) obtained by the process satisfies the following formula (I) and whose carboxyl group content is 0 to 0.3% by weight. and an anionic copolymer aqueous emulsion (B^1) containing the anionic surfactant in a solid content ratio of 0.6 to 2.5% by weight based on the copolymer; The film forming temperature (T^2) obtained by emulsion polymerization of an unsaturated monomer mixture using an anionic surfactant that forms a chelate compound with a valence metal ion satisfies the following formula (II), and Carboxyl group content is 0
An aqueous emulsion of a copolymer having an amount of ~0.3% by weight, and further containing the anionic surfactant in a solid content ratio of 0.6 to 2.5% by weight based on the copolymer. It is a mixed emulsion with an anionic copolymer aqueous emulsion (B^2), and the copolymer aqueous emulsion (B^2) is a mixed emulsion.
The mixing ratio of the copolymer aqueous emulsion (B^1)/the copolymer aqueous emulsion (B^2) is (10 to 45)/(9
0 to 55) of the mixed emulsion, the total solid content of the copolymer is 10 to 50 parts by weight, and (C) an inorganic compound that generates polyvalent metal ions in water.
~100 parts by weight of the aqueous copolymer emulsion (B^1) at a temperature higher than the minimum film forming temperature or glass transition temperature (T^1) of the copolymer of the aqueous copolymer emulsion (B^1). B^2) The copolymer is mixed at a temperature lower than the minimum film forming temperature (T^2) to form slurry, and the resulting slurry is filtered and dehydrated under the above temperature conditions to be used as a hydrous ceramic base material. The obtained hydrated green body is molded to form a ceramic molded body and then dried at a temperature exceeding the minimum film forming temperature (T^2) of the copolymer of the copolymer aqueous emulsion, or the hydrated ceramic is By either method of heating and press-molding the dried material of the raw material at a temperature exceeding the minimum film forming temperature (T^2) of the copolymer of the above-mentioned copolymer aqueous emulsion (B^2). After molding, a glaze aqueous dispersion containing a glaze and an anionic resin aqueous emulsion is applied onto the surface of the obtained dry ceramic green body molded body, followed by firing, thereby at least firing the green body and removing the glaze. A method for manufacturing ceramics characterized by firing and firing at the same time. Formula (I): (slug temperature -45℃) <T^1 < (slug temperature)
・・・・・・・・・・・・・・・・・・・・・・・・(
I) In formula (I), T^1 is the minimum film-forming temperature of the copolymer of the copolymer emulsion (B^1), or when the minimum film-forming temperature of the copolymer is below the freezing temperature of the slurry. is the glass transition temperature of the copolymer. Formula (II): (Slug temperature)<T^2・・・・・・・・・・・・・・・
(II) In formula (II), T^2 is the lowest film-forming temperature of the copolymer of the copolymer aqueous emulsion (B^2). (2) After drying and solidifying the aqueous glaze dispersion layer after glazing in the method according to the first claim, a pattern for transfer is transferred onto that surface by a water slide method, or further, a transfer surface of the pattern is transferred. 2. The manufacturing method according to claim 1, wherein the aqueous glaze dispersion is coated again and then fired to simultaneously perform firing of the green base, firing of the glaze, and firing of the pattern. (3) The ceramics according to claim 1 or 2, wherein the aqueous glaze dispersion is an aqueous dispersion prepared by mixing 100 parts by weight of the glaze with 4 to 20 parts by weight of an anionic resin aqueous emulsion in terms of resin solid content. manufacturing method.