JPH0816178B2 - Polymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polymer containing a clay mineral having a bactericidal action. More specifically, a clay mineral-containing polymer containing an exchangeable cation of an interlayer cation that retains a metal ion having a bactericidal action, has little change in physical properties, is excellent in bactericidal action, and is applicable to a wide range of polymers. It is provided.

[Prior Art] Organic polymers have many different chemical structures ranging from solids to highly viscous liquids, and are currently widely used as products. However, these polymers are susceptible to attack by microorganisms because their networks and foams allow the accumulation of water and nutrients. Under these circumstances, efforts have been made to impart various antibacterial properties to these polymers, but the mechanism is roughly divided into the elution type that acts by elution from the polymer into water, such as diphenyl ether. There are two types of non-elution type that do not elute from the polymer such as organic silicon ammonium salt.

In the elution type, since the antibacterial agent itself elutes, it has a safety effect on the human body and affects the surroundings. Further, since the antibacterial agent is eluted and the content of the antibacterial agent in the polymer is decreased, the antibacterial activity has a drawback.

On the other hand, the non-eluting type does not have these drawbacks and is considered to be preferable as an antibacterial agent. Traditionally silver ion,
Metal ions such as copper ions and zinc ions are known to have antibacterial activity, and if these metal ions are retained in a polymer to impart antibacterial activity, they are expected to be widely used as non-eluting antibacterial agents. can do. Examples of the method for holding the metal ion in the polymer include, for example, a method in which the metal powder itself is added to the polymer as a method for holding the metal itself, or an organic functional group having ion exchange ability or complex forming ability is added to the polymer. There is a method in which the organic functional group is allowed to contain a metal ion so as to retain the metal ion.

However, the method of using a metal itself with respect to a polymer has a drawback that it is not well compatible with a polymer, and since a relatively large amount is required, the weight increases and the cost becomes high. Further, a method of incorporating an organic functional group having an ion exchange ability or a complex forming ability into a polymer, and retaining a metal ion in the organic functional group, the interaction between the organic functional group and the polymer cannot be ignored, In order to avoid a remarkable change in the physical properties of the polymer, the type of the polymer and the type and amount of the organic functional group have to be within a very narrow range.

[Problems to be Solved by the Invention] As a result of intensive studies conducted by the present inventors in view of such circumstances, a polymer containing a clay mineral holding a metal ion having a bactericidal action has the above-mentioned drawbacks. Based on this finding, the present invention has been completed.

[Means for Solving the Problems] That is, the present invention is a polymer body containing a clay mineral retaining one or more metal ions having a bactericidal action.

 The configuration of the present invention will be described below.

Clay minerals used in the present invention are layered silicate minerals belonging to the smectite genus in which interlayer cations can be exchanged, and generally include montmorillonite, beidellite, nontronite, saponite and hectorite, which are natural or synthetic. It may be any of the products.

Commercially available products include Kunipia, Smecton (both Kunimine Industries), Veegum (Vanderbilt), Laponite (Laporte), tetrafluorosilicon mica (Topy Industries) and the like.

In carrying out the present invention, one or more of these clay minerals are arbitrarily selected and used.

Cations such as sodium ions and lithium ions usually exist between the layers of these clay minerals and electrically neutralize the entire clay mineral, but these cations are exchangeable, and other cations are easily exchanged. Can be replaced. This cation exchange capacity is approximately 60 to 100 g of clay mineral.
It is 150 meq.

Metal ions having a bactericidal action used in the present invention,
It is silver, copper or zinc. One or more of these metal ions are arbitrarily selected and used.

The polymer used in the present invention is a synthetic or semi-synthetic organic polymer and is not particularly limited. Examples of these include thermoplastic synthetic resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyamide, polyester, polyvinyl alcohol, polycarbonate, polyacetal, ABS resin, acrylic resin, fluororesin, polyurethane elastomer, and polyester elastomer. Examples thereof include thermosetting synthetic polymers such as molecules, phenol resins, urea resins, melamine resins, unsaturated polyester resins, epoxy resins and urethane resins, and regenerated or semi-synthetic polymers such as rayon, cupra, acetate and triacetate.

The clay mineral-containing polymer of the present invention comprises a clay mineral retaining metal ions having a bactericidal action and an organic polymer.

The proportion of the clay mineral retaining the metal ion having the bactericidal action of the present invention is preferably 0.01 to 50% by weight, more preferably 0.05 to 40% by weight, based on the polymer.

The method for producing the polymer of the present invention is not particularly limited, but it can be obtained, for example, by the following method. That is, a method of holding a metal ion having a bactericidal action in a clay mineral and adding and mixing it to an organic polymer, or a method in which a clay mineral is added and mixed to an organic polymer and molded and then the polymer molded body is subjected to ion exchange. Examples thereof include a method of treating to retain metal ions having bactericidal activity in a clay mineral in a polymer.

More specifically explaining these, as the former production method, chlorides such as silver, zinc and copper, nitrates, sulfates,
A water-soluble metal salt such as acetate is dissolved in water and / or an organic solvent, the water-swelling clay mineral is dispersed therein, the precipitated clay mineral is dispersed, and if necessary, washed and dried to sterilize. A clay mineral retaining a metal ion having an action is obtained. As the organic solvent, common ones such as ethanol, methanol and acetone are used. The concentration of the water-swellable clay mineral at the time of production is not particularly limited, but if it is 20% by weight or more, stirring becomes difficult and ion exchange becomes difficult.

The exchange amount of metal ions is preferably the same as the cation exchange capacity, but even about 10% by weight thereof can exhibit antibacterial activity. When ion exchange is performed with such a metal cation, the clay mineral loses its gelling ability even when dispersed in water.

Further, even if metal ions other than silver, copper, and zinc, such as sodium, potassium, calcium, or other metal ions, do not interfere with the bactericidal effect, there is no problem with the remaining or coexistence of these ions.

Next, the clay mineral retaining metal ions is added to and mixed with the organic polymer to obtain the polymer of the present invention. The mixing ratio is preferably 0.05 if the exchange ratio is small due to the exchange amount of metal ions, but is generally 0.05.
It may be up to 10% by weight. The timing and method of addition and mixing are not particularly limited. The point is that an optimal method may be adopted depending on the properties of the polymer to be used, the characteristics in the process, and the like.
Usually, a method of adding and mixing immediately before molding is suitable. However, in some cases, it may be preferable to add and mix with the monomer for good dispersion of the particles.

Next, as the latter production method, the clay mineral is added to and mixed with the polymer without ion exchange treatment. The timing and method of addition and mixing are not particularly limited. The obtained clay mineral-containing polymer is formed into a molded body and then subjected to ion exchange treatment. The type and shape of the molded body are not particularly limited, and may be, for example, an intermediate molded body such as pellets, or the shape of the final product. The treatment method is basically the same as the above-mentioned ion exchange treatment method for clay minerals, and the clay mineral-containing polymer molded body is treated with a solution of a water-soluble salt of a metal having a bactericidal action.

In the polymer of the present invention, in addition to the above-mentioned essential components, an organic solvent, a polymerization catalyst, a stabilizer, a matting agent, a whitening agent, an organic or inorganic pigment, an inorganic filler, various plasticizers, etc. You may mix | blend in the range which does not impair an effect.

The polymer of the present invention can be molded into various shapes and sizes. For example, granular bodies, films, fibers, various containers, pipes, and any other molded body can be used, and can be used in an extremely high range for applications requiring sterilizing power.

Further, since the polymer of the present invention also has the original function of the clay mineral, it is possible to use the antibacterial property and the original function of the clay mineral together. For example, it is possible to utilize the combined effect of moisture absorption / adsorption effect of the original function of clay mineral and antibacterial effect.

It is also possible to contain other functional substances to exert a combined function of the above effects and other functions. Other functional substances include activated carbon and silica gel.
The deodorizing / adsorbing effect is enhanced in the case of activated carbon, and the moisture absorbing effect is enhanced in the case of silica gel.

[Effects of the Invention] In the present invention, the metal ions having bactericidal activity are dispersed and held in the polymer body using the clay mineral as a carrier, so that the metal ions are widely distributed as compared with the method using the metal itself. It has a characteristic that the effect is great. Moreover, since the metal ions are stably retained in the clay mineral for a long period of time, the bactericidal effect is excellent in long-term sustainability, and thus it can be applied to various polymer bodies and is highly industrially applicable.

EXAMPLES Next, the present invention will be described in more detail with reference to examples. The present invention is not limited to these. Prior to the examples, the test method will be described below.

(1) Antibacterial activity evaluation test method The shake flask method was used to evaluate the antibacterial activity. That is, 1.5 g of phosphate buffer (PH 7.2) 70 ml inoculated with 1 to 2 × 10 ⁴ (co / ml) of test bacteria was cut into small pieces of the polymer body containing clay mineral as a sample. Add ± 0.1 g. twenty five
Shaking was performed at ± 2 ° C., and the viable cell count after 6 hours was measured to determine the reduction rate of viable cell count.

A; Viable cell count per 1 ml after shaking B; Viable cell count per 1 ml before shaking Both the viable cell count and pre-culture were made with Nutrient Agar (Difco
Company) was used.

Staphylococcus aureus, Klebsiella p
neumoniae, Pseudomonus aeruginosa, Escherichia coli
Was used.

(2) The antifungal test was carried out by the wet method of the fungus resistance test method specified in Jis-Z-2911-1976. That is, the mold spore dispersion liquid was sprayed onto the sample clay mineral-containing polymer molded product, and the sample was observed after culturing at 28 ± 2 ° C and humidity (RH) 95 ± 5% for 28 days, and the results are shown in the table. Displayed as 1.

As the test bacteria, Aspergillus niger, Penicillium fu
niculosum was used. For preculture, potato dextrose agar medium (Eiken) was used.

Table 2 shows a list of the prepared clay minerals holding metal ions having a bactericidal action.

The preparation method is 51.0 if the silver ion is retained.
g, copper sulfate (pentahydrate) to retain copper ions 37.
5 g, when retaining zinc ions, 44.6 g of zinc nitrate (hexahydrate) is dissolved in ion-exchanged water 3, 100 g of clay mineral is dispersed therein, and the mixture is stirred for 5 hours. After that, the precipitate was filtered, washed with water, dried at 100 ° C., and pulverized to obtain the above-described clay mineral carrying metal ions.

Example 1 Antibacterial Polyurethane Foam A standard polyether paste polyurethane foam for the present invention is prepared as follows.

First, the component “A” and the component “B” are prepared. Component "A" is toluene diisocyanate having an isocyanate index of 105 and component "B" is the following mixture.

Boranol CP3810 (Dow Chemical Company) 100 parts by weight Deionized water 4.5 Nearx A-1 (Union Carbide Co.) 0.09 Silicon surfactant (Shin-Etsu Silicone F-258) 0.8
 Methylene Chloride 3.25 Generally, the conventional method is to place this "B" component in a suitable container.
And homogenize using a stirrer such as a disper.
It Then add ingredient "A" and add "A" and "B" again.
Homogenize. Let the foam expand in the container
It

The antibacterial clay mineral content in the present invention is 100% polyol.
Expressed as a ratio to parts. The portion to which the antibacterial clay mineral is added during the manufacturing process may be the component "A" or "B", but it is essential to mix them homogeneously.

A sample containing the antibacterial clay mineral shown in Table 2 was prepared by the above polyurethane foam manufacturing method, and the antibacterial property was evaluated. The results are shown in Table 3.

In the shake flask method, Staphylococcus aureus,
Using Pseudomonus aeruginosa, As
pergillus niger was used.

Further, the above sample was washed according to JIS L-0217 (method 105), and after repeating 50 times, the antibacterial property was evaluated and the results are shown in Table 4.

As is clear from Tables 3 and 4, it is confirmed that the clay mineral-containing polymer of the present invention has a strong antibacterial activity and is durable.

Example 2 Antibacterial Polyurethane Film A polyurethane film was prepared by the following method.

Polyisocyanate solution * 100 parts by weight Dimethylformamide (DMF) 10 Methylethylketone (MEK) 20 * Takenate 300 (Takeda Pharmaceutical Co., Ltd.) When uniformly mixing the above, the antibacterial viscosity mineral of the present invention is added.
0.1 or 0.5 parts was added. Approximately 70 parts of the mixture on release paper.
μ was applied and a film was formed with a dryer (80 ° C.).

The results of evaluating the antibacterial activity of the prepared samples are shown in Table-5.

The bacteria used in this test are St
Aphylococcus aureus and Klebsiella pneumoniae are Penicillium funiculosum in the fungus resistance test.

Example 3 Antibacterial PVF Sponge A predetermined amount of antibacterial clay mineral is added to an aqueous solution of polyvinyl alcohol, and starch is added as a foam forming agent.
Formaldehyde was bound using hydrochloric acid as a catalyst, and a porous elastic body of polyvinyl formal was obtained by a formalization reaction. This was washed with water to remove the bubble generating agent and then dried to obtain a sample. The results of antibacterial evaluation are shown in Table-6.

Staphylococc for the test bacteria by the shake flask method
Us aureus and Escherichia coli were used, and Aspergillus niger was used in the fungus resistance test.

Washing was carried out 50 times in the same manner as in Example 1, and the results of the same test as above are shown in Table 7.

As described above, it is confirmed that the polymer containing the antibacterial metal-containing clay mineral according to the present invention has a strong antibacterial property and the antibacterial property is maintained even after washing.

Example 4 6 Nylon dried chips (relative clay 2.3 / 95% sulfuric acid) were mixed with a predetermined amount of antibacterial metal-containing viscous mineral, and the antibacterial activity was evaluated after melt spinning according to a conventional method. However, Klebsiella pneumoniae was used as the test bacterium in the shake flask method, and Penicillium funiculosum was used in the mold resistance test. The results of antibacterial activity are shown in Table-8.

Example 5 According to the method for producing a urethane foam shown in Example 1, metal-free Laponite (Laporte), 0.5
Partly blended urethane foam was foamed. Take 10 g of the above urethane foam and add 0.1 g of silver nitrate to 100 ml of deionized water.
It was dipped in the solution dissolved in and kept under stirring at room temperature for 20 hours for cation exchange. The urethane foam after the cation exchange treatment was thoroughly washed with water, dried, and evaluated for antibacterial activity. The results are shown in Table-9. The test bacteria are the same as in Example 1.

As described above, the site for imparting antibacterial metal ions to the clay mineral, even after blending the clay mineral into the polymer,
The antibacterial activity is maintained, and the addition site of the antibacterial metal ion to the clay mineral in the present invention has a good antibacterial activity even in the production method shown in the second method.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Michihiro Yamaguchi, 1050 Shinba-cho, Kohoku-ku, Yokohama-shi, Kanagawa, Shiseido Research Institute Co., Ltd. Shiseido Research Institute Examiner Hiroyuki Taniguchi (56) Reference JP 62-195038 (JP, A) JP 62-195037 (JP, A) JP 62-7748 (JP, A)

Claims (2)

[Claims] 1. A water-swellable clay mineral in which one or more metal ions having a bactericidal action are held between layers is 0.01 to 50.
A polymer body characterized by containing by weight. 2. The polymer according to claim 1, wherein the metal ion having a bactericidal action is silver, copper or zinc.