JP3243814B2 - Method for producing antibacterial phosphate intercalation compound - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention, preparation of the novel antibacterial phosphate intercalation compound having antibacterial activity against various bacteria
Regarding the method , more specifically, since it is stable to heat and various solvents, as an antibacterial composition mixed with various binders, or as an antibacterial processed product supported on fibers, paper, film, plastic, etc. The present invention relates to a method for producing an antibacterial phosphate interlayer compound that can be used.

[0002]

2. Description of the Related Art Conventionally, organic antibacterial compounds such as benzalkonium chloride and cetylpyridinium chloride have been used.
Quaternary ammonium salts, alcohols such as ethanol and isopropanol, aldehydes such as formalin and glyoxal, phenols such as carboxylic acid, cresol and xylenol, carboxylic acids such as sorbic acid and benzoic acid, chlorhexidine and n-dodecylguanidine acetate, etc. Guanidines and many others are known.

[0003]

However, the above-mentioned organic antibacterial compounds have poor heat resistance, relatively high vapor pressure, and high solubility in water and other solvents. For these reasons, it is not suitable for applications that require heating, such as kneading into resins or fibers, or for applications that attempt to maintain antibacterial effects for long periods of time in open spaces or running water. there were.

[0004] The present invention has been made in view of such conventional problems, and by increasing the heat resistance and lowering the vapor pressure and solubility of the conventional organic antibacterial compound, it is possible to obtain resins, fibers and the like. The purpose of the present invention is to provide a method for efficiently producing an antibacterial agent which can be kneaded into the composition and has a long lasting antibacterial effect.

[0005]

[Means for Solving the Problems] To achieve the above object,
As a result of intensive studies, the present inventors have found that an interlayer compound obtained by intercalating a quaternary ammonium ion into a layered phosphate has many advantages such as heat stability and stability to a solvent in addition to having an antibacterial effect. That there is even this
In producing, a layered phosphate and quaternary ammonium
Quaternary ammonium ions by contact with aqueous salt solution
Before the intercalation,
Phosphoric acid with ion or alkyl ammonium ion
By substituting exchangeable ions in the salt,
Efficient ion exchange with quaternary ammonium ions
That is, the present invention has been made.

That is, the present invention provides a fourth having antibacterial activity
Is converted to a general formula M ⁴ (HPO ₄ ) _2.
nH ₂ O (.n = 0~2 showing the M4 is a tetravalent metal in the formula)
In by replacing a part or all of ion-exchangeable ions in the layered phosphate represented, anti fungal phosphate intercalation compound that allowed intercalated layered phosphate
In the method for the production of, the ion exchange in the layered phosphate
Some or all of the ions are alkali metal ions or
After pre-substitution with an alkyl ammonium ion,
Contacting with a quaternary ammonium salt aqueous solution
I do.

The quaternary ammonium ion having an antibacterial action in the present invention is a monovalent cation in which four carbon bonds are directly bonded to a nitrogen atom, such as an alkyltrimethylammonium ion, a dialkyldimethylammonium ion, Alkyldimethylethylammonium ion, alkyldimethylbenzylammonium ion,
Alkylpyridinium ion, alkylquinolium ion, alkylamidopropyldimethylbenzylammonium ion, benzyldimethyl p- (1,1,3,3-
(Tetramethylbutylphenoxy) ethylammonium ion and the like. These are usually provided by quaternary ammonium salts such as chloride, bromide, iodide. These quaternary ammonium ions may intercalate not only one kind but several kinds to the layered phosphate.

As the layered phosphate serving as a support for quaternary ammonium ions, a phosphate of a tetravalent metal such as zirconium phosphate or titanium phosphate may be used alone or in the form of a phosphate.
A mixture of more than one species can be used. Phosphate of tetravalent metal is
A. Clearfield, G. Alberti and U. Costantino, “Inor
ganic Ion Exchange Materials ”, edited by A. Clearfield,
An overview is given in CRC Press, USA, Chapter 3 (1982), but the general formula M ⁴ (HPO ₄ ) ₂ . It is represented as nH ₂ O (M ⁴ in the formula represents a tetravalent metal), and α-form monohydrate, γ-form dihydrate and the like are generally well known. These are solid acids which are hardly soluble in water and have cation exchange ability. The proton exchange capacity of the hydrogen phosphate group (HPO ₄ ^2- ) is responsible for the ion exchange capacity, and the theoretical ion exchange capacity of α-type zirconium phosphate (hereinafter abbreviated as α-ZrP) is 6.64 me.
q / g, α-type titanium phosphate (hereinafter abbreviated as α-TiP) is 7.76 meq / g, and γ-type zirconium phosphate is 6.2.
7meq / g, and γ-type titanium phosphate (hereinafter abbreviated as γ-TiP) are 7.25 meq / g.

In the present invention, the reaction in which a quaternary ammonium ion is intercalated into a layered phosphate is considered to be an ion exchange reaction with a proton of a hydrogen phosphate group. In the production of the antibacterial phosphate intercalation compound of the present invention, a part or all of the ion-exchangeable protons may be replaced by quaternary ammonium ions by an ion exchange method, such as a general batch method or a column method. It can be carried out at normal temperature to high temperature by the method described in At this time, part or all of the ion-exchangeable protons in the layered phosphate are previously substituted with an alkali metal ion such as Na ion or an alkyl ammonium ion such as n-butyl ammonium ion. by using it, the ion exchange between the quaternary ammonium ion is more efficient line Ukoto
I can . As described above, after the quaternary ammonium ions are intercalated into the layered phosphate by ion exchange, the solid phase is separated by filtration, washed with water to remove unreacted quaternary ammonium ions, and then dried. Thus, a layered phosphate obtained by intercalating a quaternary ammonium ion, that is, an antibacterial phosphate intercalation compound of the present invention can be obtained.

[0010]

EXAMPLES Next, the present invention will be described in detail with reference to examples. However, the present examples are described only for illustrative purposes, and the present invention is not limited to these examples.

In the antibacterial test in Examples, the minimum inhibitory concentrations (hereinafter abbreviated as MIC) for various bacteria were measured by an agar dilution method. The measurement was carried out by the following method: 10 ml of an ordinary agar medium having a different concentration of the antibacterial composition was prepared in a sterilized petri dish. A fixed amount of the test bacterial solution is placed on each of these media, dried, and cultured at 30 ° C. Then, when there is no change (proliferation or decrease) in the state of the bacterium, the minimum concentration (MIC) of the antimicrobial composition-containing concentration is determined from the medium in which growth is completely inhibited.

As a test strain, Staphylococcus aureus
(Staphylococcus aureus), Escherichiacoli (Escherichia coli), Kle
bsiella pneumoniae and Pseudomonas aeruginosa
(Pseudomonas aeruginosa) was used.

The interlayer distance is measured by a powder X-ray diffraction method for confirming the intercalation, and the differential heat / thermal balance measurement (DTA-T) is performed for confirming the improvement of the thermal stability.
G) was performed. The quaternary ammonium content was determined by conversion from the total nitrogen content obtained by chemical analysis.

Production Example 1 Alkylbenzyldimethylammonium ion (alkyl group: C ₈ H _{17 to} C _{18) as a} quaternary ammonium ion
The H _37), were used, respectively gamma-TiP as layered phosphate. 10 g of γ-TiP is placed in 500 ml of a 1% aqueous solution of alkylbenzyldimethylammonium chloride (benzalkonium chloride) and stirred at room temperature for about 5 hours.
Intercalation was performed. Next, this solid phase was separated by filtration, washed with water and dried to obtain an antibacterial phosphate interlayer compound A. The content of the alkylbenzyldimethylammonium ion was 8.4%.

Production Example 2 Production Example 1 except that α-ZrP was used as the layered phosphate and that ultrasonic dispersion was used instead of stirring.
In the same manner as in the above, antibacterial phosphate interlayer compound B was obtained. The content of the alkylbenzyldimethylammonium ion was 9.3%.

Production Example 3 An antibacterial phosphate intercalation compound was prepared in the same manner as in Production Example 1 except that cetylpyridinium ion was supplied as quaternary ammonium ion by cetylpyridinium chloride, and stirring was performed at 80 ° C. for 1 hour. C was obtained. The content of cetylpyridinium ion was 10.1%.

Production Example 4 An antibacterial phosphate interlayer compound D was obtained in the same manner as in Production Example 1 except that cetyltrimethylammonium ion was supplied as quaternary ammonium ion using cetyltrimethylammonium bromide. The content of cetyltrimethylammonium ion was 8.2%.

Production Example 5 Cetylpyridinium ions were supplied as quaternary ammonium ions by cetylpyridinium chloride.
As the layered phosphate, α-TiP in which about 50% of the ion exchange capacity was previously substituted with n-butylammonium ions was used. Otherwise in the same manner as in Production Example 1, antibacterial phosphate interlayer compound E was obtained. The content of cetylpyridinium ion was 30.3%.

The antibacterial test was carried out on the antibacterial phosphate intercalation compounds A to E obtained in the above Preparation Examples 1 to 5 and the quaternary ammonium salt itself used as a conventional product in each Preparation Example. The results are shown in Table 1 in terms of quaternary ammonium ion concentration. Small ones as antimicrobial force of the MIC values but it can be said that a strong, quaternary antibacterial properties phosphate intercalation compound A~E be compared with ammonium salts has no way inferior antibacterial activity.

In particular, the antimicrobial properties obtained by the production method of the present invention
The bacterial phosphate intercalation compound E is a quaternary ammonium ion.
Content is higher than that of compounds A to D,
The results of the antibacterial test 1 also exclude P. aeruginosa (Pseudomonas aeruginosa).
Have better antibacterial activity than Compounds A to D
You.

Table 2 shows the change in the interlayer distance due to the intercalation of quaternary ammonium ions of the layered phosphate determined by the powder X-ray diffraction method. Any of the antibacterial phosphate interlayer compounds has an increased interlayer distance and can be confirmed to be intercalated.

Further, from the results of the DTA-TG measurement shown in Table 3, the endothermic or exothermic peak accompanied by weight reduction based on the quaternary ammonium ion was observed in any of the antibacterial phosphate intercalation compounds A to E. The fact that the quaternary ammonium salt is recognized at a higher temperature than the quaternary ammonium salt itself indicates that the thermal stability is improved.

[0023]

[0024]

As described above, the antibacterial phosphate intercalation compound of the present invention has higher heat stability and is less soluble in various solvents than the conventional quaternary ammonium salt-based antibacterial agent. Therefore, it can be used not only as a powder or granular material, but also by adding and processing various plastics, papers, fibers, and other base materials to impart antibacterial performance to the base material. The range can be expected to be very wide. In particular, according to the production method of the present invention, the quaternary ammonium
Antibacterial phosphoric acid with high muion content and excellent antibacterial activity
A salt intercalation compound can be obtained.

Continuation of the front page (56) References JP-A-5-246772 (JP, A) JP-A-1-282109 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C01B 25 / 37 CA (STN)

Claims (1)

(57) [Claims] 1. A quaternary ammonium ion having an antibacterial action is represented by a general formula M ⁴ (HPO ₄ ) ₂ .nH ₂ O (wherein M ⁴ represents a tetravalent metal; n = 0 to 2). by replacing a part or all of ion-exchangeable ions in the layered phosphate method smell anti fungal phosphate intercalation compound that allowed intercalated layered phosphate
Of the ion-exchangeable ions in the layered phosphate
Are all alkali metal ions or alkyl ammonium
Quaternary ammonium
Antimicrobial phosphoric acid characterized by contact with aqueous salt solution
A method for producing a salt intercalation compound .