JP2608238B2 - Stable sodium percarbonate, method for producing the same, and bleaching detergent composition containing stable sodium percarbonate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing sodium percarbonate having excellent stability and storage stability, a sodium percarbonate produced by the method, and a bleaching detergent composition containing the same. More specifically, the present invention relates to a method for producing sodium percarbonate which can be suitably blended as a main component of a bleaching agent or in a detergent, including a step of treating the surface of sodium percarbonate particles using a specific coating agent in a water slurry state.

[0002]

2. Description of the Related Art Sodium percarbonate is well known as a main base compounded in an oxygen-based bleach composition or a disinfectant composition or as an oxidizing agent itself. Produced by the action of hydrogen peroxide, the general formula 2Na
₂ CO ₃ · 3H ₂ O _2, which is obtained by adding hydrogen peroxide to sodium carbonate. Compared to chlorine bleach, sodium percarbonate has a slight decrease in bleaching power at room temperature, but it can be used for bleaching colored patterns, it does not damage the fabric and it does not yellow the fabric Therefore, it is widely used in home or commercial bleach compositions.

Another reason why sodium percarbonate has attracted attention is that its decomposition products are completely non-polluting and do not cause pollution problems such as wastewater pollution.

[0004] However, sodium percarbonate is unstable and has problems such as a decrease in activity during storage. In addition, when a trace amount of metals such as iron and copper are present as impurities, the activity of sodium percarbonate is reduced more rapidly because these act as catalysts. In recent years, due to the problem of environmental pollution in closed water bodies, low-phosphorus, non-phosphorus-free detergents using synthetic zeolites instead of phosphorus compounds as detergent builders have become widespread. However, since zeolite also acts as a catalyst, sodium percarbonate becomes very unstable in a detergent containing zeolite, and rapidly loses available oxygen due to the catalytic decomposition action of the zeolite.

[0005] Sodium perborate is known as a base for other oxygen-based bleach compositions of sodium percarbonate. This sodium perborate can be blended relatively stably in a detergent composition or the like, but because of its low solubility, it is necessary to increase its use temperature, so in countries where water work such as washing is performed at a low temperature. Almost no sodium perborate is used as a base in bleach compositions.

Therefore, if sodium percarbonate having excellent solubility at low temperatures can be stably incorporated into a detergent composition, bleaching can be performed simultaneously with washing, which is advantageous. There is a strong demand for the development of a technology for improving the storage stability of corn.

Hitherto, many studies have been made on the stabilization of sodium percarbonate, and various methods have been proposed. For example, in British Patent No. 1575792,
It is disclosed to use boric acid (orthoboric acid, metaboric acid, tetraboric acid) as a peroxide coating agent,
Japanese Patent Publication No. 61-4879 discloses the use of an aqueous borate solution as a peroxide coating agent. Also,
Japanese Patent Publication No. 3-52795 discloses that an aqueous borate solution is used for coating sodium percarbonate, and that sodium percarbonate is coated using a composite aqueous solution containing a borate and a silicate. Is disclosed. Further, in the above publication, in addition to these coating agents, an aqueous solution of a composite coating agent in which sodium carbonate or the like is further dissolved as a second component or a third component is used for coating sodium percarbonate, and the aqueous solution is used as a percarbonate. A method of spraying and treating on soda is described.

[0008]

Among the techniques for stabilizing sodium percarbonate, sodium percarbonate produced by the method disclosed in British Patent No. 1575792 is known to have storage stability, coating strength and solubility. It is not enough in terms of. In addition, JP-B 61-4879, JP-B 3-5
Although sodium percarbonate produced by the method described in No. 2795 has a remarkably improved storage stability when it is incorporated into a detergent composition, it still has a stability comparable to that of sodium perborate. It has not been achieved and was not always satisfactory.

In addition, a bleaching detergent composition containing a coated sodium percarbonate has been studied. For example, JP-A-58-217599 describes a bleaching detergent composition containing sodium percarbonate whose surface is coated with a coating composition containing borate. However, this publication states that the method of coating sodium percarbonate is not specified for the surface-coated sodium percarbonate blended in the bleaching detergent composition. It is described that a coating treatment of sodium percarbonate is performed using an aqueous solution.

[0010]

Means for Solving the Problems The present inventors have found that when sodium percarbonate is added to a bleaching composition or a detergent composition, particularly a zeolite-containing detergent composition, the storage stability of perboric acid is reduced. As a result of intensive studies to obtain sodium percarbonate having excellent storage stability, which is equal to or higher than the storage stability when soda is blended, the use of a specific coating method shows that the storage stability is excellent. The inventors have found that sodium carbonate can be obtained, and have completed the present invention.

That is, according to the present invention, the surface of sodium percarbonate is
At least one coating agent selected from the group (A) consisting of borate and alkali metal silicate; and at least one coating agent selected from the group (B) consisting of carbonate, bicarbonate and sulfate Wherein the at least one coating agent selected from the groups (A) and (B) is used as an aqueous slurry coating agent. Method, stable sodium percarbonate produced by the production method, and a powder detergent composition containing a surfactant as an essential component, and containing the stable sodium percarbonate produced by the production method of the present invention. A bleaching detergent composition is provided.

According to one embodiment of the present invention, the following (A)
At least one kind of coating agent is selected from each of the group and the group (B), and these are mixed with water to obtain a water content of 30 to 90.
This is a production method in which a slurry-like coating composition is prepared by weight% and the surface of sodium percarbonate is coated with the slurry-like coating composition. (A) group: borate and alkali metal silicate (B) group: carbonate, bicarbonate and sulfate In this case, the mixing ratio of the coating agent of group (A) and the coating agent of group (B) is weight (A) / (B) = 1/20 to 20/1 in a ratio, and the total amount of the coating agent is 0.1% based on sodium percarbonate.
-30% by weight, and the average particle size of the coating agent of group (B) is preferably in the range of 10-500 µm.

Further, embodiments of the production method of the present invention will be described below. Treating the surface of sodium percarbonate with the coating agent of the group (A);
It contains the coating agent of the group (B) and water, and has a water content of 30.
The coating is carried out with an aqueous slurry-like coating material having a dispersoid content of up to 90% by weight and at least one of the coating materials of the groups (A) and (B). The treatment of the surface of the sodium percarbonate is carried out by using an aqueous slurry coating agent containing at least one coating agent selected from the group (A) or the group (B) as a dispersoid, the group (A) or the group (B). The treatment is performed with an aqueous solution of a coating agent containing at least one coating agent selected from the group as a solute. A step of coating the surface of sodium percarbonate with an aqueous slurry coating agent, the coating step comprising: at least one coating agent selected from the group (A) consisting of borate and alkali metal silicate; , At least one coating agent selected from the group (B) consisting of bicarbonate and sulfate, and at least one coating agent selected from the group (A) and the group (B) It is used as a dispersoid of the aqueous slurry coating agent.

The raw material sodium percarbonate used in the present invention is prepared by a reaction between sodium carbonate and hydrogen peroxide in an aqueous medium, a reaction product is separated by filtration, and the product is dried. An aqueous solution of sodium carbonate and hydrogen peroxide are sprayed and reacted, and the mixture is dried as it is. Sodium percarbonate crystal particles obtained by these methods include, for various purposes, silicates, organic chelating agents, phosphates, polyacrylates, magnesium added during the reaction or after filtration or after drying. A salt or the like may be contained.

In the present invention, the borate which can be used as the coating agent (A) is preferably a sodium salt. Sodium tetraborate (borax, Na ₂ O.2B ₂ O ₃ ), sodium octaborate (Na ₂ O ・ 4B ₂ O ₃ ), sodium pentaborate (Na ₂ O ・ 5B ₂ O
₃ ), sodium metaborate (NaBO ₂ ), etc., with sodium metaborate being particularly preferred. These borates include anhydrous salts and hydrated salts, but are not particularly limited.
Among alkali metal silicates that can be used as the coating agent (A), sodium silicate is Na ₂ O · nSiO ₂ .xH ₂ O (n = 0.5
To 4, n is one represented by a molar ratio of SiO ₂ / NaO), for example, ortho sodium silicate _{(2Na 2 O · SiO 2 ·} xH 2 O, n = 0.5), sesquicarbonate sodium silicate (3Na ₂ O · _{2 SiO 2 · xH 2 O, n} = 0.67), metasilicate soda _{(Na 2 O · SiO 2 ·} xH 2 O, n = 1) crystalline sodium silicate, such as, _{and, Na 2 O · nSiO 2 (} n = 1 Non-crystalline sodium silicate represented by (4) to (4). These are commercially available as aqueous solutions and powders obtained by drying them.
Incidentally, as the coating agent (A), a borate and an alkali metal silicate can also be used in combination, and the weight ratio thereof is borate /
Alkali metal silicate = 20/1 to 1/1, preferably 1
0/1 to 1/1.

Examples of the carbonate which can be used as the coating agent (B) include sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate, etc., preferably sodium carbonate, and particularly preferably an anhydrous salt. Examples of the bicarbonate that can be used as the coating agent (B) include, for example, sodium bicarbonate and potassium bicarbonate, and preferably sodium bicarbonate. Further, examples of the sulfate that can be used as the coating agent (B) include sodium sulfate, potassium sulfate, magnesium sulfate, calcium sulfate and the like, and preferably sodium sulfate and magnesium sulfate.

In order to prepare an aqueous slurry coating suitable for use in the present invention, the finer the particle size of the coating powder, the better. In particular, as the coating agent of group (B), those having an average powder particle size of 3 to 500 μm are preferably used.
It is more preferable to use one having a thickness of 500 μm, and it is particularly preferable to use one having a range of 10 to 200 μm from the viewpoint of workability.

The ratio of the coating agent (A) to the coating agent (B) (the ratio of the total amount of each) is (A) / weight ratio.
(B) = 1/20 to 20/1 is preferable, and 1/10 to 1
0/1 is more preferable, and 1/5 to 5/1 is particularly preferable.

The total amount of the coating agent is preferably 0.1 to 30% by weight, more preferably 1 to 20% by weight, particularly preferably 2 to 20% by weight based on sodium percarbonate.

A feature of the present invention is that at least one of these coating agents is slurried and coated on the surface of sodium percarbonate.

The aqueous slurry coating agent in the present invention comprises the coating agent (A) and / or the coating agent (B) and water, and at least one of the coating agent (A) and the coating agent (B). Refers to fine solid particles that are mixed in an aqueous solution of the coating agent (A) and / or the coating agent (B) and have fluidity. Specifically, since the coating agent is present in an amount exceeding the dissolvable amount, the coating agent is in a state of being dispersed in an aqueous solution of the coating agent, and the coating agent is in an undissolved stage before complete dissolution. In a state of being dispersed in an aqueous solution of the coating agent, or fine solid particles of the above-mentioned coating agent which are not dissolved, and finer solids precipitated from the aqueous solution due to stimulus such as temperature change, agitation or temporal change. A slurry in which particles are mixed and dispersed in an aqueous solution of a coating agent and have fluidity can be given.

In the present invention, at least one kind of coating agent selected from coating agents (A) and (B) is used as an aqueous slurry coating agent, and finally, both coating agents (A) and (B) are used. It is characterized by being coated with sodium carbonate. Further, one of the coating agents (A) and (B) can be used as an aqueous slurry coating agent in the other powder. However, aqueous solutions of both coating agents (A) and (B), aqueous solutions and powders, and combinations of powders and powders are excluded in the present invention.

Specifically, the treatment of the sodium percarbonate surface is as follows:
It is carried out with at least one kind of coating composition selected from the following group. (1) An aqueous slurry coating composition comprising the group (A) coating agent and the group (B) coating agent, wherein at least one of the coating agents is present as a dispersoid. (2) The (A) An aqueous slurry coating composition containing a group of coating agents; and an aqueous solution containing the group (B) coating agent. (3) an aqueous slurry coating composition containing the group (B) coating agent. An aqueous solution containing the coating agent of the group (A); (4) an aqueous slurry coating composition containing the coating agent of the group (A); and an aqueous slurry containing the coating agent of the group (B). Coating composition (5) Aqueous slurry coating composition containing the coating agent of the group (A) and powder of the coating agent of the group (B) (6) Contains the coating agent of the group (B) Aqueous slurry coating composition to be coated and powder of the coating agent of group (A) When using the composition,
The order of treatment with the coating composition is not limited. The amount of solids dispersed in the aqueous slurry coating is generally 1% by weight or more, preferably 2 to 50% by weight, more preferably 2 to 20% by weight. At that time, the water content of the aqueous slurry coating agent is 30 to 90% by weight, preferably 50 to 70% by weight. When an aqueous slurry coating having a water content of less than 30% by weight is used, not only the effect of the present invention is not obtained but also it becomes difficult to uniformly add the aqueous slurry coating to the raw material sodium carbonate. It is not advantageous also in workability.

In the present invention, when the coating agent is slurried, water as a dispersion medium and the coating agent component are subjected to kneading and shearing under high-speed rotation to form the coating agent component into fine solid particles. This is not the case if more uniform and fine solid particles can be produced.

In the sodium percarbonate coating composition (slurry) usable in the present invention, in addition to water and the coating component, ethylenediaminetetraacetic acid, nitrilotriacetic acid, hydroxyethyliminodiacetic acid, etc. May be contained. The amount of sequestering agent to be contained is preferably 0.01 to 3% by weight based on sodium percarbonate. The sequestering agent is added to the slurry-like coating composition, but if a coating aqueous solution is used separately, it may be added to the coating aqueous solution.

The method of coating sodium percarbonate in the present invention is not particularly limited. For example, sodium percarbonate is put into a batch-type stirring mixer, and at least one coating agent (A) is added thereto while stirring. And coating agent (B)
Can be easily produced by gradually adding a slurry-like coating composition containing

The average particle size of the coated sodium percarbonate produced by the method of the present invention is usually from 100 to 200.
0 μm, preferably 250 μm, depending on the purpose of use.
１０００1000 μm or 300 to 1200 μm. In particular, from the viewpoint of storage stability and solubility, the average particle size of the coated sodium percarbonate is preferably 300 to 1200 μm. When the average particle diameter is larger than 1200 μm, the dissolving time during use is too long to sufficiently exhibit bleaching performance. On the other hand, when the average particle diameter is smaller than 300 μm, the coated sodium percarbonate contains other components. When it is blended, the storage stability due to the contact of the component particles other than the coated sodium percarbonate with the coated sodium percarbonate becomes susceptible.

The coated sodium percarbonate of the present invention preferably has a narrow particle size distribution, ie, ± 2% of the average particle size.
It is preferable that the coated sodium percarbonate particles are contained at a weight fraction of 30% or more between 00 μm.

The stable sodium percarbonate of the present invention, that is, the coated sodium percarbonate, can be used in a bleaching detergent composition, especially under severe conditions in which a decomposition catalyst such as zeolite coexists. Shows stability equal to or higher than sodium borate. This is just as surprising, as this level of stability could not be reached with the prior art.

As a result, a stable bleaching detergent composition containing sodium percarbonate was obtained for the first time.
A powder detergent composition containing a surfactant as an essential component, and at least one selected from the group (A) consisting of stable sodium percarbonate produced by the production method of the present invention, that is, borate and alkali metal silicate. The surface is treated with one kind of coating agent and at least one kind of coating agent selected from the group (B) consisting of carbonates, bicarbonates and sulfates, and the groups (A) and (B) The present invention provides a bleaching detergent composition comprising a stable sodium percarbonate produced by a production method, wherein at least one kind of coating agent selected from the group consisting of:

Among the surfactants used in the bleaching detergent composition of the present invention, nonionic surfactants include the following compounds: polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl phenyl ether, Oxyethylene sorbitan fatty acid ester,
Polyoxyethylene sorbite fatty acid ester, polyethylene glycol fatty acid ester, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene castor oil, polyoxyethylene alkylamine,
Glycerin fatty acid esters, higher fatty acid alkanolamides, alkyl glucosides, alkyl amine oxides and the like can be mentioned. Among these, the main non-ionic surfactant includes 10 to 15 carbon atoms, preferably 12 to 14 carbon atoms.
An ethylene oxide adduct of a linear or branched primary or secondary alcohol having an average ethylene oxide mole number of 5 to 15, preferably 6 to 12,
More preferably, it is desirable to use 6 to 10 polyoxyethylene alkyl ethers.

Examples of the anionic surfactant include alkyl benzene sulfonate, alkyl or alkenyl ether sulfate, alkyl or alkenyl sulfate, α-olefin sulfonate, α-sulfo fatty acid salt or ester salt, and alkyl or alkenyl ether carboxylic acid. Examples thereof include salts, amino acid type surfactants, N-acyl amino acid type surfactants, alkyl or alkenyl phosphates and salts thereof.

As the amphoteric surfactant, an amphoteric surfactant such as a carboxy type or a sulfobetaine type is used. As the cationic surfactant, a quaternary ammonium salt [for example, di (hardened tallow alkyl) dimethylammonium chloride or European Patent Quaternary ammonium salt described in No. 239910]
And an alkylamine or a hydrochloride thereof (eg, an alkylamine described in JP-A-4-108174).

The bleaching detergent composition of the present invention contains 1 to 99% by weight of stable sodium percarbonate. Also,
The surfactant is incorporated in the powder detergent composition in a range of less than 60% by weight. Here, the powder detergent composition refers to a composition containing all components other than stable sodium percarbonate in the bleaching detergent composition. The bleaching detergent composition of the present invention contains 5 to 59.4% by weight of a surfactant and 1-4 to 4% of stable sodium percarbonate.
0% by weight, more preferably 10 to 50% by weight of a surfactant and 2 to 2% of stable sodium percarbonate.
20% by weight.

The bleaching detergent composition of the present invention may contain a bleaching activator. Examples of the bleaching activator include glucose pentaacetate; organic peracid precursors such as acetic acid esters of polyhydric alcohols such as sorbitol hexaacetate and sucrose octaacetate; N-acetyl compounds such as tetraacetylethylenediaminetetraacetylglycoluril; Organic acid anhydrides such as acid and succinic anhydride; JP-B-63-12520
And the bleaching activators described in JP-A-3-17196.

The content of the bleaching activator is 1 to 50% by weight in the total bleaching detergent composition when the content of stable sodium percarbonate exceeds 40% by weight in the total bleaching detergent composition. , Preferably 5 to 40% by weight. When the amount of stable sodium percarbonate is 1 to 40% by weight in the total bleaching detergent composition, it is 0.1 to 20% by weight in the total bleaching detergent composition, and preferably 0.5 to 20% by weight. -10% by weight. The stability of the sodium percarbonate of the present invention in the bleaching detergent composition of the present invention containing a bleach activator is equal to or higher than the stability of sodium perborate.

Further, the following stabilizers (i) to (iii) are
By containing the bleaching detergent composition of the present invention as one of the detergent components, the function of the inactivating factor of sodium percarbonate in the composition system can be hidden, so that the effect of stabilizing sodium percarbonate is further enhanced. . (i) a carboxyl group-containing polymer compound (average molecular weight: 2,
000-200,000, carboxyl group content: 30
Here, a carboxyl group content of 30 mol% or more means that there are 0.3 carboxyl groups per unit monomer.

(Ii) Organic phosphonic acid or a salt thereof (iii) Aminopolycarboxylic acid or a salt thereof having a stability constant to Cu of 3 or more The compounding amount of the stabilizer is 0.1 to 15% by weight in the powder detergent composition. %, Preferably 1 to 10% by weight.

The components that can be incorporated in the bleaching detergent composition of the present invention include, for example, the following.

[1] Aluminosilicates (1) Crystalline aluminosilicate (zeolite) represented by the following formula x (M ₂ O ′ or M ″ O) · Al ₂ O ₃ .y (SiO ₂ )
• w (H ₂ O) [wherein, M ′ is an alkali metal atom, M ″ is an alkaline earth metal atom that can be exchanged for calcium, x, y, and w represent the number of moles of each component. , 0.7 ≦ x ≦ 1.5,
0.8 ≦ y ≦ 6, w is an arbitrary positive number. Among the crystalline aluminosilicates represented by the above formula, the detergent builder is particularly preferably one represented by the following general formula.

Na ₂ O.Al ₂ O ₃ .y (SiO ₂ ) .w (H ₂ O) wherein y represents a number of 1.8 to 3.0 and w represents a number of 1 to 6. ] (2) amorphous aluminosilicates represented by the following formula _{x (M 2 O ') ·} Al 2 O 3 · y (SiO 2) · w (H
₂ O) [wherein, M represents a sodium atom and / or a potassium atom, x, y, and w represent the number of moles of each component, and 0.7 <
x ≦ 1.2, 1.6 ≦ y ≦ 2.8, w is an arbitrary positive number. Such an aluminosilicate promotes decomposition of sodium percarbonate, but the sodium percarbonate provided by the present invention has a stability equal to or higher than that of sodium perborate, even in the presence of aluminosilicate. Is shown.

[2] Detergent builder Examples of the detergent builder include phosphates such as tripolyphosphate and pyrophosphate; aminotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphone). acid),
Diethylenetriaminepenta (methylenephosphonic acid) and salts thereof; salts of phosphonocarboxylic acids such as 2-phosphonobutane-1,2-dicarboxylic acid; salts of amino acids such as aspartic acid and glutamic acid; nitrilotriacetic acid salts and ethylenediaminetetraacetic acid salts And the like. Further, polyelectrolytes such as polyacrylic acid and polyaconitic acid, non-dissociated polymer substances such as polyethylene glycol, polyvinyl alcohol and polyvinylpyrrolidone; polyacetal carboxylic acid polymers described in JP-A-54-52196; diglycolic acid; Divalent metal ion scavenger such as organic acid salt such as carboxylate; alkaline agent such as silicate, carbonate and sulfate or inorganic electrolyte;
Layered silicate according to 27895, polyvinylpyrrolidone,
Anti-recontamination agents such as carboxymethyl cellulose,
As a detergent builder.

[3] Heavy metal sequestering agent, for example, hydroxyiminodiacetic acid [4] Bleaching stabilizer ethylenediaminetetraacetic acid, etc. [5] Enzyme Protease, amylase, lipase, cellulase, etc. Acid salts, talc, calcium silicate, etc. [7] Antioxidants tert-butylhydroxytoluene, distyrenated cresol, etc. [8] Fluorescent dyes, bluing agents, fragrances and the like.

These are not particularly limited, and may be blended according to the purpose.

The bleaching detergent composition according to the present invention is usually obtained by producing detergent composition particles only with components other than the coated sodium percarbonate, ie, the detergent component, and then mixing the coated sodium percarbonate with the particles. .

In the bleaching detergent composition of the present invention, in order to reduce the deterioration of the storage stability of the coated sodium percarbonate due to the contact between the detergent composition particles and the coated sodium percarbonate, the particle size of the bleached detergent is as similar as possible. It is preferable to use detergent composition particles and coated sodium percarbonate particles. Therefore, the detergent composition particles preferably have an average particle size of 250 to 900 μm and are close to the average particle size of the coated sodium percarbonate. Further, both the coated sodium percarbonate particles and the detergent composition particles preferably have a narrow particle size distribution, and preferably contain particles at a weight fraction of 30% or more between ± 200 μm before and after the average particle diameter. Further, the water content of the detergent composition particles is desirably 8% by weight or less, preferably 6% by weight or less. If the water content of the detergent composition particles exceeds 8% by weight, the stability of the sodium percarbonate particles tends to decrease.

When the particle diameter of the detergent composition itself falls within an arbitrary range, the particle diameter may be used as it is. However, when the particle diameter is too large, it is pulverized. Granulated by a suitable method and, if necessary, sized. The detergent composition particles are not limited to one type, and two or more types of particles containing a part of the detergent components may be separately granulated, and a mixture thereof may be used as the detergent composition particles.

In the bleaching detergent composition of the present invention as described above, the coated sodium percarbonate of the present invention has particularly good stability.
The bleaching detergent composition shows excellent bleaching detergency even after long-term storage.

[0049]

Although the details of the mechanism of action in the present invention are not known, when the coating agent is coated on sodium percarbonate using a solution, the coating agent solution passes through the gaps between crystals on the surface of the sodium percarbonate. Due to the phenomenon that penetrates inside the crystal, the crystal surface,
That is, the efficiency of coating on the surface of the sodium percarbonate particles is reduced. On the other hand, when the coating material is coated as it is, it is easily affected by the particle size of the powder, that is, the coating material. The coating layer on the surface of the sodium carbonate particles tends to be uneven. On the other hand, when at least one kind of the coating agent is spread on the surface of the sodium percarbonate in the form of a finer slurry having good fluidity as in the present invention, the coating agent is more uniformly and efficiently. Since the coating layer is formed on the surface of the sodium percarbonate, the storage stability of the coated sodium percarbonate is expected to be dramatically improved.

[0050]

The coated sodium percarbonate produced by the production method of the present invention is more stable than the case where a conventional sodium percarbonate is added to a bleaching composition or a detergent composition, particularly a detergent composition containing zeolite. And the degree of stability is equal to or higher than that of sodium perborate. That is, the bleaching detergent composition of the present invention exhibits, in terms of bleaching detergency, stability equal to or higher than that of a bleaching detergent composition containing sodium perborate as a bleaching agent. Therefore, the present invention is industrially very advantageous.

Further, in the conventional method for producing coated sodium percarbonate using only the coating solution, it was necessary to completely dissolve the coating in the solvent. Despite the limitations, according to the present invention, these limitations are completely eliminated.

[0052]

EXAMPLES The present invention will be described below with reference to examples, but the present invention can be embodied without being limited thereto.

[Raw material sodium percarbonate] The wet sodium percarbonate obtained by reacting hydrogen peroxide and sodium carbonate in an aqueous solution was dried with hot air to obtain a raw material sodium carbonate.

Examples 1 to 6 4.5 kg of sodium percarbonate was placed in a stirring mixer (batch type), and stirred at 250 rpm, and water 5 was added thereto.
A coating agent (B) shown in Table 1 (addition ratio: percarbonate) was added to an aqueous solution in which sodium metaborate tetrahydrate [coating agent (A)] was dissolved in an amount of 5.5% by weight to sodium percarbonate. soda)
And the slurry-like coating composition produced by the kneading machine is dropped, and the mixture is dropped for 3 minutes (about 30 seconds at the time of dropping, and about 2 minutes and 30 seconds after dropping).
Stirring was continued, and the mixture was dried by flowing with hot air to obtain a coated sodium percarbonate.

The obtained coated sodium percarbonate was subjected to a storage stability test with respect to zeolite, and the obtained results are shown in Table 1. The storage stability test method for zeolite is as follows. [Test method for storage stability with respect to zeolite] 1.0 g of each sample (0.90% sodium percarbonate obtained by coating treatment)
g mixed with 0.1 g of commercially available zeolite), 50 m
After placing in a 1-volume plastic container, covering with a lid (with a pinhole), and allowing it to stand at 50 ° C. and 70% RH for 48 hours, the effective oxygen remaining rate was determined by the following equation. The available oxygen was measured using a 0.1N potassium permanganate titration method. Active oxygen remaining rate (%) = (active oxygen after storage / active oxygen before storage) × 100

[0056]

[Table 1]

Comparative Examples 1 to 3 and Reference Example 1 4.5 kg of sodium percarbonate was placed in a stirring mixer (batch type), and stirred at 250 rpm, and water 6 was added thereto.
4. 50 g of sodium metaborate tetrahydrate [coating agent (A)]
5% by weight and the coating agent (B) shown in Table 2 were added, and an aqueous solution of the coating composition obtained by dissolving at 50 ° C. was added dropwise, and the resulting mixture was dropped for 3 minutes (approximately 30 seconds after the addition, approximately 2 minutes 30 seconds after the addition). ) Stirring was continued, and the mixture was dried by flowing with hot air to obtain coated sodium percarbonate. The amount of the coating agent was shown in terms of% by weight based on sodium percarbonate. The obtained coated sodium percarbonate was subjected to a zeolite storage stability test in the same manner as in Examples 1 to 6, and the obtained results are shown in Table 2. As Reference Example 1, the results of a zeolite storage stability test of a commercially available sodium perborate (manufactured by Interox Corporation) were shown.

[0058]

[Table 2]

Comparative Examples 4 to 8 4.5 kg of sodium percarbonate was put into a stirring mixer (batch type), and stirred at 250 rpm, and at the same time, 650 g of water was added.
Was added to obtain wet sodium percarbonate, and then sodium metaborate dihydrate [average particle size 150 μm, coating agent (A)] 4.1% by weight (sodium metaborate tetrahydrate 5.5)
%) And the powder coating agent shown in Table 3 was added.
Continue stirring for about 30 minutes (approx.
Hot air flow drying was performed to obtain a coated sodium percarbonate. In addition, the addition rate of the coating agent is% by weight based on sodium percarbonate. The resulting coated sodium percarbonate was subjected to a zeolite storage stability test in the same manner as in Examples 1 to 6, and the obtained results were shown in Table 3.
It was shown to.

[0060]

[Table 3]

Examples 7 to 9 4.5 kg of sodium percarbonate was placed in a stirring mixer (batch type) and stirred at 250 rpm, and water 4 was added thereto.
A coating agent (B) (addition ratio: sodium percarbonate) shown in Table 4 was supplied to an aqueous solution in which JIS No. 3 sodium silicate [coating agent (A)] was dissolved in 50 wt. The slurry-like coating composition produced by the kneading machine was dropped, and stirring was continued for 3 minutes (approximately 30 seconds at the time of dropping, and about 2 minutes 30 seconds after the dropping), followed by hot air flow drying to obtain a coated sodium percarbonate. Was. The obtained coated sodium percarbonate was subjected to a zeolite storage stability test in the same manner as in Examples 1 to 6, and the obtained results are shown in Table 4.

[0062]

[Table 4]

Examples 10 to 19 4.5 kg of sodium percarbonate was put into a stirrer-type mixer (batch type), and stirred at 250 rpm.
Aqueous solution in which sodium metaborate tetrahydrate [coating agent (A)] and JIS No. 3 sodium silicate [coating agent (A)] are dissolved in 50 g in sodium percarbonate at 5.5% by weight and 1.5% by weight, respectively. And the slurry (B) (addition ratio: sodium percarbonate) shown in Table 5 was supplied thereto, and the slurry-like coating composition produced by the kneading machine was dropped. Thereafter, stirring was continued for about 2 minutes and 30 seconds, followed by hot-air flow drying to obtain a coated sodium percarbonate. The coated sodium percarbonate obtained according to these examples was tested for storage stability against zeolite in Examples 1 to 4.
Table 6 shows the results obtained.

[0064]

[Table 5]

Examples 20 to 23, Comparative Examples 9 and 10, and Reference Example 2 Sodium percarbonate was supplied at a flow rate of 100 kg / h to a stirring mixer (continuous type), and stirred at 200 rpm. In a kneader, 200 kg of sodium metaborate tetrahydrate [coating agent (A)] and 50 kg of JIS No. 3 sodium silicate [coating agent (A)] were dissolved in water, and an aqueous solution having a total volume of 400 liters was 14.5 liter / h. (17.8 kg /
h) at the flow rate of powder coating agent (B) shown in Table 6 (addition rate:
(Soda percarbonate) is supplied at a flow rate of 3 kg / h (Examples 20 and 23) or 5 kg / h (Examples 21 and 22) to supply a slurry-like coating composition to a kneader. Dropping was performed at a flow rate of 14.5 liter / h, coating treatment was performed, and hot air flow drying was performed to obtain a coated sodium percarbonate. The coated sodium percarbonate obtained according to these examples was tested for storage stability against detergents and the results obtained are shown in Table 6. Reference Example 2 shows the stability when a commercially available sodium perborate (manufactured by Interox) was used.

Here, the test method of the storage stability with respect to the detergent is as follows.

[Test Method for Storage Stability Against Detergent] 10 g of each sample (1 g of sodium percarbonate obtained by coating 9 g of a commercially available zeolite-containing phosphorus-free detergent) was mixed,
After placing in a 50 ml plastic container, covering with a lid (without pinholes), and allowing it to stand at 40 ° C. and 80% RH for 14 days, the effective oxygen remaining rate was determined by the following equation. The available oxygen was measured using a 0.1N potassium permanganate titration method. Active oxygen remaining rate (%) = (active oxygen after storage / active oxygen before storage) × 100

[0068]

[Table 6]

Examples 24 to 26 Sodium percarbonate was supplied at a flow rate of 100 kg / h to a stirring mixer (continuous type), and stirring was performed at 200 rpm. Sodium metaborate dihydrate [Coating agent (A), average particle size 150 μm]
5.5 kg / h (5.5% by weight based on sodium percarbonate) and 1.0 kg / h of powdered sodium silicate [coating agent (A)].
(1.0% by weight based on sodium percarbonate) and 5 kg / h (Examples 24 and 25) or 3 kg / h of the powder coating agent (B) (addition rate: sodium percarbonate) shown in Table 7 The slurry coating composition prepared by supplying at the flow rate of (Example 26) was dropped at the same flow rate as the supply flow rate to the kneader, coating was performed, and hot air flow drying was performed to obtain coated sodium percarbonate. . A test of the storage stability of the coated sodium percarbonate obtained in these examples with respect to detergents was carried out in the same manner as in Examples 20 to 23, and the obtained results are shown in Table 7.

[0070]

[Table 7]

Example 27, Comparative Examples 11 and 12 4.5 kg of sodium percarbonate was put into a stirrer-type mixer (batch type), and while stirring at 250 rpm, the following coating compositions were respectively added dropwise thereto, and the mixture was added for 3 minutes. (About 30 seconds after dropping, and about 2 minutes and 30 seconds after dropping) After stirring was continued, the resultant was dried by flowing with hot air to obtain a coated sodium percarbonate. The obtained coated sodium percarbonate was subjected to a zeolite storage stability test by the methods described in Examples 1 to 6. Table 8 shows the obtained results.

(Coating composition) Comparative Example 11: Sodium metaborate tetrahydrate [coating agent (A ₁ )] and powdered sodium silicate [coating agent] in 600 g of water
(A ₂ )] was dissolved in sodium percarbonate (abbreviated as PC in Table 8) at 6.5% by weight and 1% by weight, respectively, in aqueous solution (temperature: 70 ° C.). Comparative Example 12: An aqueous solution (temperature: 70 ° C.) in which soda ash [coating agent (B)] was further dissolved in the aqueous solution of Comparative Example 11 by 5% by weight with respect to sodium percarbonate.

Example 27: Sodium metaborate tetrahydrate [coating agent (A)] and powdered sodium silicate [coating agent (A)] were added to 430 g of water at 6.5 wt. % And 1% by weight (temperature 7
0 ° C.), and a slurry coating composition obtained by further adding 5% by weight of soda ash [coating agent (B)] to sodium percarbonate.

[0074]

[Table 8]

Examples 28 and 29, Comparative Examples 13 and 14 Coated sodium percarbonate was prepared in the same manner as in Examples 2 and 12, except that the temperature of the slurry treatment was set to 50 ° C. Was obtained (Examples 28 and 29).
These and the coated sodium percarbonate of Comparative Examples 1 and 3 were subjected to a zeolite storage stability test by the method described in Examples 1 to 6. Table 9 shows the results.

[0076]

[Table 9]

Examples 30 to 38 and Comparative Examples 15 to 19 The detergent components shown in Tables 10 to 12 were mixed, and an aqueous slurry having a solid content of 60% by weight was obtained by using them and water. The aqueous slurry was spray-dried, and the resulting detergent powder was placed in a stirring granulator and granulated to obtain detergent component particles. Each of the sodium percarbonates shown in Tables 10 to 12 was mixed with the detergent component particles to obtain a bleaching detergent composition. However, only in Example 37, sodium carbonate was not added to the aqueous slurry, and the mixture was granulated during granulation. The water content of the resulting bleaching detergent composition was as shown in Tables 10-12. Here, the moisture is derived from the powder detergent composition and is a weight reduction rate when heated at 105 ° C. for 2 hours.
Further, the particle size of the obtained granular composition (bleaching detergent composition) was determined as a weight average particle size (weighted average particle size) using a standard sieve (JIS Z8801), and the average particle size was determined from the determined particle size curve. The weight fraction at a diameter of ± 200 μm was calculated.

Further, a storage stability test was performed for each bleaching detergent composition by the following method. The results are shown in Tables 10 to 12.
Shown in The stability constants (PK _Cu ) for Cu of the bleaching stabilizer used are as follows. PK _Cu , poly (alpha hydroxyacrylic acid) soda ... 7.1 (Mw = 30,000, manufactured by Solvay)-Acrylic acid / maleic acid copolymer Na ... 6.8 (Mw = 70000, manufactured by BASF)-EDTA 4Na 6.2 (Storage stability test) Each of the bleaching detergent compositions obtained above was 10
g was placed in a 50 cc plastic container, closed with a lid, and allowed to stand at 50 ° C. for 20 days. In addition, for the measurement of available oxygen,
A 0.1 N potassium permanganate titration method was used. The results are shown in Tables 10 to 12. Active oxygen remaining rate (%) = (active oxygen after storage / active oxygen before storage) × 100

[0079]

[Table 10]

[0080]

[Table 11]

[0081]

[Table 12]

Examples 39 to 42, Comparative Examples 20 and 21 Among the various components shown in Table 13, the powdery raw material was put into a stirring tumbling granulator, and then a liquid nonionic activator was gradually introduced, followed by mixing. After granulation, sodium percarbonate, an enzyme, and a bleach activator (tetraacetylethylenediamine, nonanoyloxybenzenesulfonate Na) were mixed to obtain a bleaching detergent composition. The particle size of the resulting bleaching detergent composition (detergent component particles + sodium percarbonate particles + enzyme particles + bleach activator particles)
Using a standard sieve (JIS Z8801), the weight average particle size (weighted average particle size) was determined, and the weight fraction at the average particle size ± 200 μm was calculated from the obtained particle size curve.

Further, for each bleaching detergent composition, a storage stability test was conducted by the methods described in Examples 30 to 38 and Comparative Examples 15 to 19. The results are shown in Table 13. In addition, the stability constant with respect to Cu of the bleaching stabilizer used is as follows. PK _Cu. 1-hydroxyethylidene-1,1-diphosphonic acid Na ... 6.0 (manufactured by Monsanto) ・ Isoserindiacetate 3Na (manufactured by BASF) ... 7.1

[0084]

[Table 13]

Example 43, Comparative Examples 22 and 23 Each of the components and granules shown in Table 14 were mixed to obtain each bleaching agent composition. About them, Examples 30 to 38 and Comparative Example 1
A storage stability test was performed by the methods described in 5 to 19. Table 14 shows the results.

[0086]

[Table 14]

Example 44 4.5 kg of sodium percarbonate was put into a stirring mixer (batch type), and stirred at 250 rpm, and sodium metaborate tetrahydrate [coating agent (A)] and sodium silicate powder were added thereto. [Coating agent (A)] was added to sodium percarbonate in an amount of 6.5% by weight and 1.0% by weight, respectively, and a slurry coating composition (temperature: 60 ° C) produced by a kneader was added dropwise. Coated with sodium carbonate. Further, an aqueous solution (temperature: 60 ° C.) in which 5.0% by weight of soda ash [coating agent (B), average particle size: 100 μm] was dissolved in sodium percarbonate was added dropwise to 525 g of water into a stirring mixer. After stirring for about 15 minutes (approximately 15 seconds at each drop of the slurry and the aqueous solution, and about 2 minutes and 30 seconds after the drop), the mixture was hot-air-flow dried to obtain coated sodium percarbonate. The obtained coated sodium percarbonate was subjected to a zeolite storage stability test in the same manner as in Examples 1 to 6. As a result, the effective oxygen residual ratio was 93%.

Example 45 4.5 kg of sodium percarbonate was put into a stirrer mixer (batch type) and stirred at 250 rpm, and sodium metaborate tetrahydrate [coating agent (A)] and powdered sodium silicate were added thereto. An aqueous solution (temperature: 70 ° C.) in which 6.5% by weight and 1.0% by weight of [coating agent (A)] were dissolved in sodium percarbonate, respectively, was added dropwise to coat the sodium percarbonate. Further, add soda ash [coating agent (B), average particle diameter 100
μm] to sodium percarbonate at 5.0% by weight,
The slurry-like coating composition (temperature 70
℃) was dropped into a stirring mixer, and stirring was continued for 3 minutes (about 15 seconds for each drop of slurry and aqueous solution, about 2 minutes and 30 seconds after dropping), followed by hot air flow drying to obtain a coated sodium percarbonate. Was. The obtained coated sodium percarbonate was subjected to a zeolite storage stability test in the same manner as in Examples 1 to 6. As a result, the effective oxygen residual ratio was 95%.

Example 46 4.5 kg of sodium percarbonate was put into a stirring mixer (batch type), and stirred at 250 rpm, and water 3 was added thereto.
Soda ash [coating agent (B), average particle size 100μ]
m] was added dropwise to an aqueous solution (temperature: 60 ° C.) in which 5.0% by weight of sodium percarbonate was dissolved, and coated with sodium percarbonate. Further, to 50 g of water, 6.5% by weight and 1.0% by weight of sodium metaborate tetrahydrate [coating agent (A)] and powdered sodium silicate [coating agent (A)] were added to sodium percarbonate, respectively. And the slurry-like coating composition (temperature 60 ° C.) produced by the kneading machine was dropped into the stirring mixer, and stirred for 3 minutes (about 15 seconds for each drop of the slurry and the aqueous solution, and about 2 minutes 30 seconds after the dropping). After that, drying with hot air was performed to obtain a coated sodium percarbonate. The obtained coated sodium percarbonate was subjected to a zeolite storage stability test in the same manner as in Examples 1 to 6. As a result, the effective oxygen residual ratio was 93%.

Example 47 4.5 kg of sodium percarbonate was put into a stirrer-type mixer (batch type), and stirred at 250 rpm.
Soda ash [coating agent (B), average particle size 100μ]
m] was supplied to sodium percarbonate in an amount of 5.0% by weight and a slurry coating composition (temperature: 60 ° C.) produced by a kneader.
Was added dropwise to coat sodium percarbonate. 270 g of water
Aqueous solution in which 6.5% by weight and 1.0% by weight of sodium metaborate tetrahydrate [coating agent (A)] and powdered sodium silicate [coating agent (A)] are dissolved in sodium percarbonate, respectively. (At a temperature of 70 ° C.), and stirring was continued for 3 minutes (approximately 15 seconds for each drop of the slurry and the aqueous solution, and about 2 minutes and 30 seconds after the dropwise addition), followed by hot-air flow drying to obtain a coated sodium percarbonate. The obtained coated sodium percarbonate was subjected to a zeolite storage stability test in the same manner as in Examples 1 to 6. As a result, the effective oxygen residual ratio was 93%.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideo Kikuchi 2-54, Tanijima-cho, Koriyama-shi, Fukushima Prefecture Nippon Peroxide Co., Ltd. (72) Inventor Masahiro Saito 2-54, Tanijima-cho, Koriyama-shi, Fukushima Nippon Par Oxide Koriyama Plant Co., Ltd. (56) References Japanese Patent Publication No. 58-24361 (JP, B2) Japanese Patent Publication No. 1-39961 (JP, B2)

Claims (24)

(57) [Claims] 1. The surface of sodium percarbonate is coated with at least one coating agent selected from the group consisting of borate and alkali metal silicate, and a group consisting of carbonate, bicarbonate and sulfate. A step of treating with at least one kind of coating agent selected from B), and using at least one kind of coating agent selected from the groups (A) and (B) as an aqueous slurry coating agent. A method for producing stable sodium percarbonate. 2. The method for producing stable sodium percarbonate according to claim 1, wherein the water content of the aqueous slurry coating is 30 to 90% by weight. 3. The treatment of the surface of sodium percarbonate is carried out by the step (A).
Group, the coating agent of group (B) and water, the water content is 30 to 90% by weight, and at least one of the coating agents of group (A) and group (B) is used. 2. The method for producing stable sodium percarbonate according to claim 1, wherein the method is carried out with an aqueous slurry coating agent used as a dispersoid. 4. The method for producing sodium percarbonate according to claim 3, wherein the coating agent of group (A) is a borate and / or an alkali metal silicate. 5. The treatment of the surface of sodium percarbonate according to the above (A)
Aqueous slurry-type coating agent using one coating agent selected from the group or the coating agent belonging to the group (B) as a dispersoid, and coating agent using at least one coating agent of the coating agent belonging to the other group as a solute The method for producing stable sodium percarbonate according to claim 1, wherein the method is performed with an aqueous solution. 6. The weight ratio of the total amount of the coating agent of the group (A) to the total amount of the coating agent of the group (B) is (A) / (B) = 1.
The method for producing a stable sodium percarbonate according to any one of claims 1 to 5, wherein the ratio is / 20 to 20/1. 7. The coating agent according to claim 1, wherein the coating agent of the group (A) and the coating agent of the group (B) are used in a total amount of 0.1 to 30% by weight based on sodium percarbonate. A method for producing stable sodium percarbonate as described. 8. The method for producing stable sodium percarbonate according to claim 1, wherein a borate and an alkali metal silicate are used as the coating agent of the group (A). 9. The method for producing a stable sodium percarbonate according to claim 8, wherein the weight ratio of borate to alkali metal silicate is from 20/1 to 1/1. 10. A coating agent (B) having an average particle size in the range of 10 to 500 μm.
10. The method for producing a stable sodium percarbonate according to any one of claims 9 to 9. 11. A coating agent (B) having an average particle size in the range of 10 to 200 μm.
10. The method for producing a stable sodium percarbonate according to any one of claims 9 to 9. 12. A stable sodium percarbonate produced by the production method according to claim 1. 13. A stable sodium percarbonate produced by the production method according to claim 3. 14. A stable sodium percarbonate produced by the production method according to claim 5. 15. The stable sodium percarbonate according to claim 12, wherein the average particle diameter is 300 to 1200 μm. 16. A bleaching detergent composition comprising a powder detergent composition containing a surfactant as an essential component and a stable sodium percarbonate, wherein the sodium percarbonate has a surface formed of borate and alkali silicate. A step of treating with at least one coating agent selected from the group consisting of metal salts (A) and at least one coating agent selected from the group consisting of carbonates, bicarbonates and sulfates; A bleaching detergent containing the at least one coating agent selected from the group (A) and the group (B) as an aqueous slurry coating agent. Composition. 17. The powder detergent composition having an average particle size of 25.
17. The bleaching detergent composition according to claim 16, wherein the average particle size of the stable sodium percarbonate is 300 to 1200 [mu] m. 18. The composition according to claim 16, which contains 5 to 59.4% by weight of a surfactant and 1 to 40% by weight of stable sodium percarbonate.
Or the bleaching detergent composition according to 17. 19. The powder detergent composition further comprises a carboxyl group-containing polymer compound (average molecular weight: 2,000 to 2).
At least one selected from the group consisting of organic phosphonic acids, salts of organic phosphonic acids, aminopolycarboxylic acids having a stability constant for Cu of 3 or more, and salts thereof. The bleaching detergent composition according to any one of claims 16 to 18, comprising a stabilizer. 20. The bleaching detergent composition according to claim 19, wherein said powder detergent composition contains 0.1 to 15% by weight of said stabilizer. 21. The method according to claim 1, further comprising a bleach activator.
21. The bleaching detergent composition according to any one of 6 to 20. 22. The method according to claim 21, comprising 5 to 59.4% by weight of a surfactant, 1 to 40% by weight of stable sodium percarbonate, and 0.1 to 20% by weight of a bleaching activator. Bleach detergent composition. 23. Stable sodium percarbonate in excess of 40% by weight;
22. The bleaching detergent composition according to claim 21, comprising a bleach activator in a range of 1 to 50% by weight. 24. The bleaching detergent composition according to claim 16, wherein the water content in the powder detergent composition is 8% by weight or less.