JP3459833B2 - Aqueous antibacterial agent dispersion - Google Patents

Description

TECHNICAL FIELD The present invention relates to an aqueous antibacterial agent dispersion liquid, and more specifically,
The present invention relates to an aqueous antibacterial agent dispersion excellent in low-temperature storage stability, which does not lose the properties of the frozen aqueous solution of the 2-mercaptopyridine-N-oxide metal salt even when it is re-thawed.

BACKGROUND OF THE INVENTION 2-Mercaptopyridine-N-oxide metal salts are useful as fungicides, especially zinc salts (hereinafter referred to as "ZPT").
Is widely used as an anti-dandruff agent in shampoos and conditioners.

Conventionally, commercially available ZPT aqueous dispersions are generally stable at room temperature, but when they are frozen and then re-thawed, they have the drawbacks such as agglomeration and the formation of particles or a marked change in viscosity. Therefore, when transporting or storing the ZPT aqueous dispersion, it has to be handled at a temperature of 5 ° C or higher.

In particular, the ZPT aqueous dispersion liquid sometimes freezes because it sometimes becomes below freezing when it is transported to winter or cold regions or stored in winter or cold regions. After that, when it is re-thawed at room temperature to use the frozen dispersion liquid, the dispersion liquid is agglomerated, settles at the bottom of the container, particles are generated, the viscosity is remarkably increased, and the contents are removed from the container. In some cases, it could not be used as a dispersion because it did not come out.

As described above, once the frozen dispersion is re-thawed at room temperature to lose its pre-freezing properties, there is no solution except by phase separation and redispersion.
The financial loss was enormous.

Generally, ZPT is poorly soluble in water, and is mixed in the base of a hair treatment agent in the form of a suspended solid, that is, an aqueous dispersion. From the viewpoint of stabilization, it has been attempted to make ZPT into fine particles or to add an anionic polymer compound, a nonionic polymer compound, an amphoteric polymer compound, etc. (Japanese Patent Publication No. Sho 61-3518).
6, JP-A-60-16973, JP-A-61-151110, JP-A-61-151111 and JP-A-62-63). However, the dispersion thus prepared has a drawback that it sediments and solidifies at the bottom of the container during storage, and even a relatively stable dispersion is aggregated and separated due to salt contamination or freezing.

As a method for solving this, JP-A-60-139613 discloses a method of adding a polyglycol / polyamine condensation resin or a polyglycol / polyamine / alkylamine or alkyleneamine condensation resin. Specifically, according to Example 1 and Example 2 of the same specification, if Polycoat H (manufactured by Henkel) was added to 2-mercaptopyridine-N-oxide zinc salt, it aggregated even after rethawing after freezing. It is stated that it does not.

However, this method cannot be said to be an economically advantageous method because the polycoat H is used in a large amount in the same weight or more with respect to the 2-mercaptopyridine-N-oxide zinc salt.
In addition, it is not always a good method because it has a high viscosity and is inconvenient to handle, and when it is used for shampoo or rinse, compatibility with other additives in the shampoo or rinse must be taken into consideration. Further, the above-mentioned dispersion liquid is a dispersion liquid having a 2-mercaptopyridine-N-oxide metal salt concentration of about 30% by weight, which is an advantageous method in terms of transportation as compared with the commercially available ZPT concentration of 50% by weight. Absent.
Further, when the amount of resin added is small, there is no effect or insufficient effect when re-thawing after freezing.

Further, in JP-A-7-506603, a plastisol containing a resin and a carrier and a biocide are mixed and heated to a high temperature and then cooled to obtain a dispersion having excellent storage stability.

In addition, in Japanese Patent Publication No. 8-503458, a biocide and a carrier are mixed to form a concentrated liquid, which is heated to a high temperature and then cooled to obtain a mixture excellent in storage stability. It has gained.

However, in any of these methods, it is necessary to once heat to a high temperature and then to cool, so that the manufacturing process for obtaining a dispersion or a mixture is complicated. Moreover, since two kinds of resin and carrier are used, it is not an economically advantageous method. Moreover, the stability at the time of rethawing after freezing is still insufficient.

Therefore, in an aqueous dispersion of a metal salt of 2-mercaptopyridine-N-oxide, the properties of the dispersion before freezing are not lost even when used after rethawing after freezing, that is, it has excellent low-temperature storage stability. Further, there has been a demand for a dispersion liquid which can be produced by a simple method.

DISCLOSURE OF THE INVENTION In order to achieve the above object, the inventors of the present invention have conducted extensive studies, and as a result, the polyhydric alcohol and / or vinyl polymer was added to an aqueous dispersion of 2-mercaptopyridine-N-oxide metal salt at room temperature. The dispersion liquid produced by only simple operation of adding and stirring is about -5 ° C to about -30 ° C.
Even if frozen, the product will not agglomerate if it is re-thawed, will settle at the bottom of the container, will not generate granules, or the viscosity will increase significantly and the contents will not come out of the container, i.e. dispersion. It was found that an aqueous antibacterial agent dispersion liquid of 2-mercaptopyridine-N-oxide metal salt excellent in low-temperature storage stability which does not lose the properties of the liquid before freezing is obtained, and the present invention has been completed. That is, the present invention is as follows.

A metal salt of 2-mercaptopyridine-N-oxide,
Dispersion of an aqueous antibacterial agent having excellent low-temperature storage stability, which does not lose the properties of the dispersion before freezing even after rethawing after freezing, which contains a polyhydric alcohol and / or a vinyl polymer as an anticoagulant liquid.

The aqueous antibacterial agent dispersion described above, wherein the polyhydric alcohol is at least one selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and glycerin.

The aqueous antibacterial agent dispersion described above, wherein the polyhydric alcohol is glycerin.

The aqueous antibacterial agent dispersion liquid according to any one of the above 1 to 3, wherein the content of the polyhydric alcohol is 3 to 8% by weight.

The aqueous antibacterial agent dispersion described above, wherein the vinyl polymer is polyvinylpyrrolidone.

The aqueous antibacterial agent dispersion as described above or above, wherein the content of the vinyl polymer is 0.3 to 10.0% by weight.

The aqueous antibacterial agent dispersion as described above, wherein the content of the metal salt of 2-mercaptopyridine-N-oxide is 20 to 60% by weight.

The aqueous antibacterial agent dispersion described above, which is obtained by mixing a polyhydric alcohol and / or a vinyl polymer in an aqueous dispersion of a metal salt of 2-mercaptopyridine-N-oxide.

The content of the metal salt of 2-mercaptopyridine-N-oxide is 20 to 60% by weight, and the content of the polyhydric alcohol is 3
2-mercaptopyridine-N such that
An aqueous antibacterial agent dispersion as described above, which is obtained by mixing a polyhydric alcohol with an aqueous dispersion of a metal salt of oxide.

The content of the metal salt of 2-mercaptopyridine-N-oxide is 20 to 60% by weight, and the content of the vinyl polymer is 0.
The aqueous antibacterial agent dispersion described above, which is obtained by blending an aqueous dispersion of a metal salt of 2-mercaptopyridine-N-oxide with a vinyl polymer so as to be 3 to 10.0% by weight.

The aqueous antibacterial agent dispersion liquid according to any one of 1 to 3, wherein the metal of the 2-mercaptopyridine-N-oxide metal salt is zinc.

  The present invention will be described in detail below.

The aqueous antibacterial agent dispersion of the present invention comprises a metal salt of 2-mercaptopyridine-N-oxide and a polyhydric alcohol and / or a vinyl polymer as an anticoagulant.

Examples of the metal in the metal salt of 2-mercaptopyridine-N-oxide used in the present invention include zinc,
Copper, calcium, magnesium, barium, strontium, cadmium, tin, zirconium and the like,
Among these, zinc, which has been widely used conventionally, is preferable.

The metal salt of 2-mercaptopyridine-N-oxide is
The content of the antibacterial agent dispersion of the present invention is preferably 20 to 60% by weight, more preferably 30 to 50% by weight.

Examples of the polyhydric alcohol used in the present invention include glycerin, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and the like, of which glycerin is preferable.

The polyhydric alcohol is contained in the aqueous antibacterial agent dispersion of the present invention in an amount of preferably 3 to 8% by weight, more preferably 4 to 7% by weight. If the content is less than 3% by weight, the properties of the dispersion liquid before freezing may be lost when frozen and re-thawed. On the contrary, when the blending amount exceeds 8% by weight, the dispersion liquid may undergo phase separation.

Examples of the vinyl polymer used in the present invention include polyvinylpyrrolidone and polyvinyl isobutyl ether having a molecular weight of 10,000 to 40,000, and among them, polyvinylpyrrolidone is preferable.

The vinyl polymer, in the aqueous antibacterial agent dispersion of the present invention, preferably 0.3 to 10.0 wt%, more preferably 0.5 to
It is contained in the range of 5% by weight. The content is 0.3% by weight
If it is less than 100%, the properties of the dispersion before freezing may be lost when frozen and re-thawed. On the other hand, when the blending amount exceeds 10.0% by weight, the viscosity becomes high and it may be difficult to handle.

In the aqueous antibacterial agent dispersion of the present invention, an aqueous medium is used as a solvent, and examples thereof include water and a mixed solvent of water and an organic solvent such as ethanol.

The preparation of the aqueous antibacterial agent dispersion of the present invention is not particularly limited as long as it contains a 2-mercaptopyridine-N-oxide metal salt and a polyhydric alcohol and / or a vinyl polymer, but 2-mercaptopyridine-N- A polyhydric alcohol and / or vinyl polymer is added to an aqueous dispersion of an oxide metal salt at room temperature, or an aqueous dispersion of a 2-mercaptopyridine-N-oxide metal salt is added to the polyhydric alcohol and / or vinyl polymer. A method of adding at room temperature and stirring and mixing for several hours using a general stirring and mixing device such as a propeller stirring device and a homomixer is preferable. In the above-mentioned method, it is preferable to add the 2-mercaptopyridine-N-oxide metal salt and the polyhydric alcohol and / or the vinyl polymer so that the contents thereof fall within the above-mentioned ranges.

The aqueous dispersion of 2-mercaptopyridine-N-oxide metal salt used for preparing the aqueous antibacterial agent dispersion of the present invention includes:
Commonly used surfactants and thickeners can be added. These surfactants and thickeners are preferably the same as those used in shampoos, rinses, etc., and the polyhydric alcohol and / or vinyl polymer used in the present invention contains these surfactants and thickeners. It can be used in combination with an agent.

As the above-mentioned surfactant, an anionic surfactant,
Examples thereof include nonionic surfactants and amphoteric surfactants.

Examples of the anionic surfactant include carboxylate salt type (for example, N-acyl amino acid salt), sulfonate salt type (for example, olefin sulfonate salt), sulfate ester salt type (for example, lauryl sulfate salt, lauryl sulfate (polyether salt). (Oxyethylene) salt) and the like.

Examples of the nonionic surfactant include alkanolamide type (for example, fatty acid alkanolamide) and the like.

Examples of the amphoteric surfactant include carboxybetaine type (for example, alkylbetaine) and 2-alkylimidazoline derivative (for example, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine).

In addition, the rinse includes a cationic surfactant (for example,
Aliphatic quaternary ammonium salt) and the like are mainly used.

Examples of the above-mentioned thickener include cellulose derivatives (eg, carboxymethyl cellulose, hydroxyethyl cellulose), polyvinyl alcohol, naturally-occurring polysaccharides and the like.

The surfactant and the thickener are not limited to the above.

The thus obtained aqueous antibacterial agent dispersion of the present invention freezes at about -5 ° C to about -30 ° C. The resulting dispersion has excellent low-temperature storage stability, in which no matter is generated or the viscosity is significantly increased and the content does not come out of the container, that is, the properties of the dispersion before freezing are not lost.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto. Example 1
As the commercial item A of 3, Comparative Examples 1 and 2 and Test Example 1, a product "TOMICIDE ZPT-50" manufactured by Yoshitomi Fine Chemical Co. was used. This "TOMIC IDE ZPT-50" is a ZPT aqueous dispersion containing about 50% by weight of ZPT, about 50% by weight of water and a small amount of anionic surfactant.

Example 1 To 200 g of a commercial product A, 10.0 g of glycerin was added, and the mixture was stirred and mixed at room temperature using a stirrer to obtain an aqueous antibacterial agent dispersion liquid.

Example 2 10.0 g of propylene glycol was added to 200 g of a commercial product A, and the mixture was stirred and mixed at room temperature with a stirrer to obtain an aqueous antibacterial agent dispersion liquid.

Example 3 To 200 g of the commercially available product A, 1.0 g of polyvinylpyrrolidone having an average molecular weight of 10,000 was added and stirred at room temperature with a stirrer to obtain an aqueous antibacterial agent dispersion.

Comparative Example 1 200 g of a commercial product, Polycoat-H81 manufactured by Henkel (50% aqueous solution of polyglycol-polyamine condensation polymer) 2.
0 g was added and stirred at room temperature with a stirrer to obtain an aqueous antibacterial agent dispersion.

Comparative Example 2 Polycoat-H81 (50% aqueous solution of polyglycol-polyamine condensation polymer) manufactured by Henkel Corporation on 200 g of a commercial product 1
Although 0.0 g was added and the mixture was stirred at room temperature using a stirrer, the viscosity became extremely high during stirring, and stirring and mixing was impossible.

Test Example 1 Dispersions of Examples 1 to 3 and Comparative Example 1 and dispersions of commercial product A and commercial product B (dispersion having a ZPT concentration of 48% by weight, product ZINC OMADINE of Aurin Chemical Co., Ltd.) 50 each
Each g was placed in a 50 ml plastic bottle, covered with a lid and sealed, and then frozen and re-thawed under the following two conditions.

Condition 1: Starting from an initial temperature of 5 ° C, the temperature was lowered over 7 hours and cooled to -10 ° C. Then, it was left at −10 ° C. for 15 hours. At this time, the dispersion was frozen. Next, this was heated to 5 ° C. over 7 hours and remelted.

Condition 2: The sample was left in a constant temperature bath at -20 ° C for 24 hours. At this time, the dispersion was frozen. Then it was remelted at room temperature.

Then, the dispersions after freezing and rethawing under the conditions 1 and 2 were examined for the following items.

(1) Caking: It was examined whether or not there was a solid content in the plastic bottle that was hard to flow.

(2) Aggregation: The remelted material was placed on a glass plate and examined for the presence or absence of particulate matter.

(3) Phase separation: It was examined whether phase separation occurred in the plastic bottle.

The results of Condition 1 are shown in Table 1 and the results of Condition 2 are shown in Table 2.
Respectively shown.

From the test results shown in Table 1 and Table 2, the aqueous antibacterial agent dispersion of the present invention does not cause caking, aggregation and phase separation even when frozen and re-thawed, and has excellent properties at low temperature storage stability. It was revealed that

INDUSTRIAL APPLICABILITY The aqueous antibacterial agent dispersion obtained by the present invention is re-thawed even if frozen even when transported in cold regions or winter, or when stored in cold regions or winter. For example, it has very advantageous characteristics that it does not cause phase separation, flocculation, sedimentation, generation of particles, etc., and does not lose the properties of the dispersion before freezing and has excellent low temperature storage stability.

The present invention applies to Japanese Patent Application No. 125798 filed in Japan in 1997.
No., 1997 Patent Application No. 125799, 1997 Patent Application No. 1349
It is based on 37 and 1997 patent application No. 134938, the contents of which are incorporated in full herein.

─────────────────────────────────────────────────── ─── Continuation of front page (31) Priority claim number Japanese Patent Application No. 9-134938 (32) Priority date May 26, 1997 (May 26, 1997) (33) Priority claim country Japan (JP) (72) Inventor Tetsuji Ike Address: 955, Shoji, Yoshitomi-cho, Tsukigami-gun, Fukuoka Prefecture, Manufacturing Department (56) References JP-A-54-98343 (JP, A) JP-A-59-108707 (JP, A) ) JP-A-8-20733 (JP, A) JP-A-8-283622 (JP, A) JP-A-63-297315 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) A01N 25/04 A01N 43/40 101 A01N 55/02 CA (STN) REGISTRY (STN)

Claims (2)

(57) [Claims] 1. 20-60% by weight of 2-mercaptopyridine-
Metal salts of N-oxide and 0.3-10 as anti-agglomeration agent.
An aqueous antibacterial agent dispersion excellent in low-temperature storage stability, which contains 0% by weight of polyvinylpyrrolidone and does not lose the properties of the dispersion before freezing even after rethawing after freezing. 2. The aqueous antibacterial agent dispersion according to claim 1, wherein the metal of the 2-mercaptopyridine-N-oxide metal salt is zinc.