JP3981997B2 - Antibacterial resin composition and molded article - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin composition that prevents the occurrence of darkening, slime, and the like generated on the surface of a resin product due to microorganisms such as mold, yeast, and bacteria. More specifically, an antibacterial resin composition used for soap containers used in bathrooms, kitchens, toilets, etc., water-related products such as chairs, cocoons, and drainers, shampoo containers, and washing machine washing tubs. And a molded article.
[0002]
[Prior art]
Currently, antibacterial agents that can be added to resins have been developed and are already widely used. However, antibacterial agents can be broadly divided into inorganic antibacterial agents in which silver, zinc, etc. are supported on zeolite, etc., and organic compounds that have antibacterial properties. There are two types of organic antibacterial agents. As the inorganic antibacterial agent, silver is mainly used widely, and zinc is used when discoloration by light becomes a problem. These are already widely used in cutting tools, bowls and other cooking utensils, bathroom chairs, wash-basin and other water-related products, washing machine washing tubs, humidifiers and other filters and water tanks, and ballpoint pens and other stationery. ing. As the organic antibacterial agent, an imidazole antibacterial agent or a thiazoline antibacterial agent is used in a washing tub of a washing machine. Both of these inorganic antibacterial agents and organic antibacterial agents are added directly to the resin at the time of molding or as a high-concentration masterbatch and molded.
[0003]
[Problems to be solved by the invention]
Inorganic antibacterial agents are said to have high safety to the human body, and are highly useful antibacterial agents because they are highly heat resistant and are therefore not subject to restrictions when added to resins. However, since the antibacterial effect of silver on mold is small, a large amount of addition is necessary to prevent darkening due to mold. In addition, there is a problem that discoloration occurs when receiving light. Moreover, since the antibacterial effect of zinc is extremely small compared to silver, it is impossible to obtain the antibacterial effect alone.
[0004]
In the case of organic antibacterial agents, few have antibacterial properties against both mold and bacteria. For example, according to the research results of the inventors, a drug containing an antibacterial component of benzalkonium salt, which is a mixture of alkyldimethylbenzylammonium salts having different alkyl chain lengths, which is an example of quaternary ammonium, was added to polyethylene. In this case, the addition of 0.02 wt% to 2.5 wt% or more as benzalkonium ion shows an antibacterial effect against general bacteria, whereas it is necessary to add 10 times or more to mold. . In addition, butyl paraoxybenzoate, which is an example of a paraoxybenzoic acid ester-based compound, or isobutyl paraoxybenzoate, propyl paraoxybenzoate or isomer thereof, isopropyl paraoxybenzoate, ethyl paraoxybenzoate, paraoxybenzoate, which is an isomer thereof. When a single substance or a plurality of substances selected from methyl acid are added to polyethylene, it exhibits an antibacterial effect against mold at an addition amount of 0.01 to 1.0% by weight as a paraoxybenzoic acid ester compound, whereas gram No antibacterial effect was observed against Escherichia coli, which is a negative bacterium.
[0005]
In the case of organic antibacterial agents, there are also agents that have the problems of being decomposed by light and losing efficacy, causing discoloration, and reducing the strength of the added resin. In addition, there are some drugs that are easily eluted by water, and such drugs lose their antibacterial activity immediately when they come into continuous contact with water, such as water-based products. In addition, from the viewpoint of heat resistance, not all organic substances having antibacterial properties can be added to the resin, and when molding with the addition of chemicals, the degradation or loss of antibacterial activity due to thermal decomposition, discoloration of the resin and Strength degradation will occur. From the above, it is not an exaggeration to say that there is no antibacterial resin that exhibits antibacterial properties against all microorganisms over a long period of time in an environment where resin products are used.
[0006]
Therefore, the present invention provides an antibacterial resin composition and a molded product that retains good antibacterial properties against all microorganisms (mold, bacteria, etc.) over a long period of time and does not cause resin discoloration or strength reduction. For the purpose.
[0007]
[Means for Solving the Problems]
The present invention has been conceived to solve the above problems, and the invention of claim 1 is characterized in that at least one selected from quaternary ammonium salts obtained by holding a quaternary ammonium salt on an inorganic support. and agents with antimicrobial, an antibacterial resin composition characterized by containing a drug having at least one antimicrobial selected from p-hydroxybenzoic acid esters compounds absorbed held by the inorganic material.
[0008]
A second aspect of the present invention is the antibacterial resin composition according to the first aspect, wherein the inorganic support supporting the quaternary ammonium salt is a phosphate.
[0009]
A third aspect of the present invention, inorganic substances which absorb and retain the p-hydroxybenzoic acid esters compound, characterized in that it is a silicon dioxide, an antimicrobial resin composition according to claim 1, wherein.
[0010]
According to a fourth aspect of the present invention, there is provided the method according to any one of the first to third aspects, wherein the quaternary ammonium salt is an alkyldimethylbenzylammonium salt (alkyl group carbon number C8 to C18) and an alkylpyridinium salt (alkyl group carbon atom). number C8 in chosen alone or more substances from -C18), p-hydroxybenzoic acid esters compound parahydroxybenzoate butyl or parahydroxybenzoate isobutyl, propyl parahydroxybenzoate or parahydroxybenzoate isopropyl, ethyl parahydroxybenzoate, parahydroxybenzoate An antibacterial resin composition characterized by being a single substance or a plurality of substances selected from methyl acid.
[0011]
In the invention of claim 5, the content concentration is any one of claims 1 to 4, wherein the quaternary ammonium salt content concentration is 0.02 to 2.5% by weight as quaternary ammonium ions, an antibacterial resin composition, wherein the p-hydroxybenzoic acid esters compound containing concentration of 0.01 to 1.0 wt%.
[0012]
The invention of claim 6 is a molded article having a resin layer containing the resin composition of any one of claims 1 to 5.
[0013]
The invention of claim 7 is a molded article in which the resin layer of claim 6 is the outermost layer.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be specifically described. Examples of quaternary ammonium that can be used in the present invention include alkyldimethylammonium chloride (n = 1 to 17) (also known as benzalkonium chloride) as shown in (Chemical Formula 1) and (Chemical Formula 2). Alkylpyridinium chloride (n = 6 to 16) (also known as cetylpyridinium chloride) bound to a phosphate such as zirconium phosphate or titanium phosphate by ion exchange, that is, quaternary ammonium and phosphate What was made to hold | maintain on the support body of an inorganic substance, such as what was made into the state, can use suitably. The content of quaternary ammonium ions in the support is determined by the ion exchange capacity in the case of holding by ion exchange, for example, but is generally from 5% by weight to 30% by weight.
[0015]
[Chemical 1]
[0016]
[Chemical 2]
[0017]
The p-hydroxybenzoic acid esters available compounds of the present invention, a parahydroxybenzoate isobutyl, propyl parahydroxybenzoate or its isomer is parahydroxybenzoate butyl or an isomer, as shown in (Formula 3) parahydroxybenzoate A material in which a single substance or a plurality of substances selected from isopropyl benzoate, ethyl paraoxybenzoate, and methyl paraoxybenzoate are held by adsorption onto an inorganic substance such as silicon dioxide can be suitably used. About 70% to 5 wt% as the content of p-hydroxybenzoic acid esters Compounds of the holder in is suitable. The content of each antimicrobial components in the resin composition according to this invention is 0.02 wt% to 2.5 wt% quaternary ammonium salt as a quaternary ammonium ion, p-hydroxybenzoic acid esters compound 0.01 % To 1.0% by weight is suitable. There is a problem that p-hydroxybenzoic acid esters compound can not be obtained the desired antimicrobial activity is less than 0.01 wt%, it exceeds 1.0 wt% not only uneconomical, the surface of the molded article sticky There is a problem.
[0018]
[Chemical 3]
[0019]
The resin used in the present invention includes thermoplastic resins such as polyethylene, polyvinyl chloride and polypropylene, thermosetting resins such as paraoxybenzoic acid esters, melamine resins, and natural resins such as gum arabic and ceramics. Is included. Furthermore, substances that are usually added to the resin, such as an antioxidant, an ultraviolet absorber, a colorant, an antistatic agent, and a plasticizer, are not limited to the resin composition in the present invention. However, since an anionic additive reduces the effect of a quaternary ammonium antibacterial agent, it is necessary to be careful when using it.
[0020]
By quaternary ammonium and p-hydroxybenzoic acid esters compound was contained in the resin, has an antibacterial action against molds and bacteria, yet there is no such reduction in discoloration and antimicrobial by light, to obtain a resin composition be able to. Further, when the concentration of the p-hydroxybenzoic acid esters compound is 0.01 to 1.0 wt%, not antibacterial effect only good, since the surface resistance is good, with respect in particular both fungi and bacteria Excellent antibacterial properties are obtained, and the antibacterial properties are maintained for a long period of time.
[0021]
In general, when a drug having antibacterial properties against bacteria and a drug having antibacterial properties against mold are mixed, it is easy to exhibit antibacterial properties against mold and bacteria unless chemical changes occur. As can be expected, in the case of the resin composition according to the present invention, in addition to the feature of having antibacterial activity against all microorganisms, it has resistance to light, water, detergent, etc. and is excellent in moldability. Has characteristics.
[0022]
The resin composition of the present invention is used as a molded product by molding the resin composition by a molding method, and the molding is performed by blow molding, injection molding, sheet molding method or the like. The molded product may be a multilayer molded product, and the resin composition of the present invention may be used in any one of the layers. It is particularly preferable to provide the outermost layer in order to increase the efficiency of the drug.
[0023]
EXAMPLES Examples of the present invention will be specifically described below.
<Example 1> quaternary ammonium, 0.5% by weight of benzalkonium salts as benzalkonium ions, as p-hydroxybenzoic acid esters compound was butyl parahydroxybenzoate was 0.1 wt%, polypropylene sheet A sample having a thickness of about 500 μm was prepared. The benzalkonium salt used here is one in which benzalkonium chloride is supported on aluminum tripolyphosphate by ion exchange, and butyl paraoxybenzoate is supported on silicon dioxide by adsorption. It was n’t. Each was added at the time of sheet molding to achieve a desired drug concentration.
[0024]
As comparative examples, samples of Comparative Examples 1 to 4 were prepared.
<Comparative Example 1> A polypropylene sheet having only a thickness of about 500 µm was prepared.
In the same manner as <Comparative Example 2> Example 1, as a p-hydroxybenzoic acid esters compound, butyl parahydroxybenzoate was 0.1 wt%, to prepare a polypropylene sheet (thickness of about 500 [mu] m).
Comparative Example 3 A polypropylene sheet (thickness: about 500 μm) containing 0.5% by weight of benzalkonium as quaternary ammonium was prepared in the same manner as in Example 1.
Comparative Example 4 A polypropylene sheet having a thickness of about 500 μm was prepared, containing 0.5% by weight of thiabendazole (TBZ) as an antibacterial substance against mold and 0.5% by weight of zinc pyrithione (ZPT) as an antibacterial ingredient against bacteria. Each antibacterial component was mixed and molded into a resin pellet so as to have a desired content during sheet molding.
[0025]
[Experiment 1] Using the above five samples, the following experiment was conducted. Penicillium citrinum IFO 6352 spores as mold indicator fungi, and the same species as Methylobacterium extorquens (Furuhata et al .: Antibacterial fungus, 18, 407-410 (1990)) isolated from red slime that occurs on the bathroom floor as a bacterial indicator Methylobacterium extorquens IFO 3708 cells were each smeared on an agar medium, and the samples of Examples and Comparative Examples were punched into a circle having a diameter of 10 mm, closely adhered to the medium, and cultured. Potato dextrose agar was used for molds and standard agar was used for bacteria. The mold culture temperature was 25 ° C., and the bacteria culture temperature was 30 ° C. After culturing for 1 week, the presence or absence of halo (inhibition circle, Fig. 1) was observed. If it has antibacterial properties, a halo (blocking circle) (3) is formed. Table 1 shows the observation results.
[0026]
[Table 1]
[0027]
[Experiment 2] On the other hand, 100 hours of light exposure was carried out with a xenon weather meter manufactured by Suga Test Instruments, and antibacterial properties were measured in the same manner as in Experiment 1. The degree of visual discoloration was also recorded. Table 2 shows the observation results.
[0028]
[Table 2]
[0029]
As a result of Experiment 1, as shown in Table 1, by adding the antibacterial agent effective against bacteria and the antibacterial agent effective against mold, including the resin composition according to the present invention, both bacteria and molds can be added simultaneously. It was shown that it is possible to obtain a resin composition having an antibacterial action. However, as a result of Experiment 2, as shown in Table 2, it was shown that if they were simply mixed, they were deteriorated by light, causing discoloration and antibacterial deterioration, and the resin composition according to the present invention was excellent.
[0030]
<Example 2> A polyethylene bottle (23) having a capacity of 800 ml having a composition of the resin composition layer (21) / non-added layer (22) according to the present invention was prepared from the outside of the container by a conventional multilayer blow molding method, and used as a sample. (FIG. 2). The composition ratio was set to 1: 9 from the outside of the container, and the basis weight was set to 55 g. Resin composition layer according to the invention in the same manner as in Example 1 was butyl parahydroxybenzoate were added 0.1% by weight p-hydroxybenzoic acid esters compounds. However, as the quaternary ammonium salt, cetylpyridinium chloride supported on tripolyphosphoric acid by ion exchange was used, and added as 1.0% by weight as cetylpyridinium.
[0031]
As comparative examples, samples of Comparative Examples 5 to 7 were prepared.
<Comparative Example 5> A polyethylene bottle (33) having a basis weight of 55 g and a capacity of 800 ml was produced by a normal blow molding method (FIG. 3).
<Comparative Example 6> A polyethylene bottle (43) having a capacity of 800 ml having an antibacterial agent-added resin layer (41) / non-added layer (42) configuration was produced from the outside of the container by a conventional multilayer blow molding method (FIG. 4).
). The composition ratio was set to 1: 9 from the outside of the container, and the basis weight was set to 55 g. In the same manner as in Example 3, the antibacterial agent-added resin layer used was a quaternary ammonium salt in which cetylpyridinium chloride was supported on tripolyphosphoric acid by ion exchange so that the cetylpyridinium was 1.0% by weight. Added.
<Comparative Example 7> A polyethylene bottle (53) having a capacity of 800 ml having an antibacterial agent-added resin layer (51) / non-added layer (52) configuration was produced from the outside of the container by a conventional multilayer blow molding method (FIG. 5). The composition ratio was set to 1: 9 from the outside of the container, and the basis weight was set to 55 g. Antimicrobial additive resin layer in the same manner as in Example 3, was butyl parahydroxybenzoate were added 0.1% by weight p-hydroxybenzoic acid esters compounds.
[0032]
[Experiment 3] Using the above four samples (containers of Example 3 and Comparative Examples 5, 6, and 7), the following experiment was performed. The observation results are shown in Table 3 in which the container was left in a bathroom of a general household and the occurrence of darkening and slime was observed.
[0033]
[Table 3]
[0034]
As a result of Experiment 3, as shown in Table 3, even when the resin composition according to the present invention was actually applied and used, the effect of preventing slimming and darkening was shown.
[0035]
【The invention's effect】
By using the resin composition according to the present invention, it is possible to prevent both darkening due to mold growth and slime due to bacterial growth, and is not affected by discoloration due to light, etc. Can be produced.
[0036]
In particular quaternary ammonium salt is an alkyl dimethyl benzyl ammonium salt (also known as benzalkonium chloride) and alkyl pyridinium: alone selected from (also known as cetyl pyridinium chloride) or more substances, paraoxybenzoates compound parahydroxybenzoate (Butyl acetate or isobutyl paraoxybenzoate), propyl paraoxybenzoate or isopropyl paraoxybenzoate, ethyl paraoxybenzoate, or methyl paraoxybenzoate, so that quaternary ammonium salts are used for bacterial growth. a p-hydroxybenzoic acid esters compound for inhibiting the growth of mold, provides excellent antimicrobial against molds and bacteria, yet the antimicrobial that is maintained for a long time. Moreover, the effect is quaternary ammonium salt-containing concentration 0.02 to 2.5% by weight, economical and molded product containing a concentration of p-hydroxybenzoic acid esters compound is 0.01 to 1.0 wt% Since the surface state of this is good, the effect becomes remarkable.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a halo in a halo (inhibition circle) method, which is one of antibacterial assay methods.
FIG. 2 is an explanatory view showing an example of a container using the resin composition according to the present invention. (Example 2)
FIG. 3 is an explanatory view showing an example of a container that does not use the resin composition according to the present invention. (Comparative Example 5)
FIG. 4 is an explanatory view showing another example of a container that does not use the resin composition according to the present invention. (Comparative Example 6)
FIG. 5 is an explanatory view showing another example of a container that does not use the resin composition according to the present invention. (Comparative Example 7)
[Explanation of symbols]
1: Petri dish 2: Fungus growth area 3: Hello (inhibition circle)
4: Resin (test piece)
21: Antibacterial agent added resin layer 22: Antibacterial agent non-added resin layer 23: Bottle 33: Bottle 41: Antibacterial agent added resin layer 42: Antibacterial agent non-added resin layer 43: Bottle 51: Antibacterial agent added resin layer 52: Antibacterial agent Unadded resin layer 53: Bottle

Claims (7)

A drug having at least one antimicrobial which a quaternary ammonium salt selected from quaternary ammonium salts comprising by holding the carrier inorganics selected from p-hydroxybenzoic acid esters compounds absorbed held by the inorganic substance An antibacterial resin composition comprising at least one antibacterial agent.   2. The antibacterial resin composition according to claim 1, wherein the inorganic support supporting the quaternary ammonium salt is a phosphate. Inorganic absorbing retain paraoxybenzoates compound, characterized in that it is a silicon dioxide, according to claim 1 antibacterial resin composition. 4. The quaternary ammonium salt according to claim 1, wherein the quaternary ammonium salt is selected from an alkyldimethylbenzylammonium salt (alkyl group having C8 to C18) and an alkylpyridinium salt (alkyl group having C8 to C18). in a single or multiple substances, paraoxybenzoates compound parahydroxybenzoate butyl or parahydroxybenzoate isobutyl, propyl parahydroxybenzoate or parahydroxybenzoate isopropyl, ethyl parahydroxybenzoate, alone selected from methyl parahydroxybenzoate Alternatively, an antibacterial resin composition comprising a plurality of substances. Content level, in any one of claims 1 to 4, quaternary ammonium salt-containing concentration is 0.02 to 2.5 wt% as a quaternary ammonium ion, p-hydroxybenzoic acid esters compound containing An antibacterial resin composition having a concentration of 0.01 to 1.0% by weight.   A molded article having a resin layer containing the resin composition according to any one of claims 1 to 5.   The molded article according to claim 6, wherein the resin layer is an outermost layer.

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