JPH10140012A - Antibacterial resin composition and molded article - Google Patents

Abstract

(57) [Summary] [Object] An antibacterial resin composition containing an antibacterial agent such as silver,
To provide a resin composition having no discoloration over time in a molded product and a molded product. SOLUTION: In a resin composition containing an inorganic powder antibacterial agent containing silver ions, barium sulfate, calcium oxide, calcium silicate, calcium sulfate, zinc oxide,
And an antibacterial resin composition containing at least one white powder pigment selected from the group consisting of zinc silicate and zinc silicate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition and a molded article containing an antibacterial agent powder comprising an inorganic component having antibacterial properties such as silver and a white powder pigment.

[0002]

2. Description of the Related Art Many techniques are known for molding a synthetic resin by adding an antibacterial agent thereto. It is disclosed that an inorganic powder antibacterial agent containing silver or the like having particularly high heat resistance and excellent antibacterial durability is applied (JP-A-59-133235 and others). A resin composition containing an inorganic powder antibacterial agent containing silver or the like has a drawback that it is susceptible to a change caused by chemical reactivity of silver and a change caused by energy such as light and heat. In particular, in the resin composition, among the stabilizers added to stabilize the physical properties of the resin, there are sulfur compounds and phosphate compounds having high reactivity with silver, which causes discoloration. was there. However, it is difficult to remove the silver component from the viewpoint of the antibacterial effect, it is also difficult to sufficiently stabilize the silver in the antibacterial agent, and it is difficult to obtain a resin composition molded article that does not cause discoloration over time. there were.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an antibacterial resin composition and a molded article containing an antibacterial agent such as silver, which do not discolor over time, and a molded article. It is.

[0004]

Means for Solving the Problems The present inventors have made intensive studies in view of the above problems, and as a result, by adding a specific white pigment to a resin composition containing an inorganic antibacterial agent powder containing silver and the like, The present inventors have found that discoloration of an antibacterial agent can be prevented by a masking effect, and have completed the present invention. The present invention
In a resin composition containing an inorganic powder antibacterial agent containing silver ions, at least one white powder selected from the group consisting of barium sulfate, calcium oxide, calcium silicate, calcium sulfate, zinc oxide, and zinc silicate An antibacterial resin composition containing a pigment, and a molded product obtained from the resin composition.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below. As an inorganic powder antibacterial agent containing silver ions used in the present invention, a powder in which silver ions are supported on an inorganic carrier can be exemplified. Examples of the inorganic carrier include crystalline aluminosilicate (hereinafter, referred to as “zeolite”), amorphous aluminosilicate (hereinafter, referred to as “AAS”), silica gel,
Activated alumina, diatomaceous earth, activated carbon, zirconium phosphate, hydroxyapatite, magnesium oxide, magnesium perchlorate, etc. can be mentioned, but aluminosilicate is chemically stable and can contain a high concentration of silver component. (Zeolite and AAS) are preferably used. The inorganic powder antibacterial agent contains silver ion in an amount of 0.1% by weight or more, usually 1.5 to 10% by weight, and 0.5% by weight or more, usually 0.5 to 8% by weight based on the resin composition. Addition by weight% is preferred from the viewpoint of antibacterial performance.

[0006] The white powder pigment used in the present invention is at least one selected from the group consisting of barium sulfate, calcium oxide, calcium silicate, calcium sulfate, zinc oxide and zinc silicate. The particle size of the white powder pigment used in the present invention is preferably 1 μm or less, and more preferably 0.1 to 0.8 μm, because it is easy to incorporate into a resin and has good dispersibility. The specific surface area of the white powder pigment is at least 8 m ² / g, preferably 15 to 5
It is preferably 0 m ² / g from the viewpoint of good hiding properties when added to the resin.

The resin used in the resin composition of the present invention includes an ionomer resin, an EEA resin (ethylene-ethyl acrylate copolymer), an EVA resin, a vinyl chloride resin, a vinylidene chloride resin, a chlorinated polyethylene, a fluorine resin, and a polyamide resin. , Polyetheretherketone, polysulfone, polyethylene, polycarbonate,
Examples include hydrophobic resins such as polybutadiene, polypropylene, polystyrene, polyacrylate, polyurethane, and polyethylene terephthalate, and hydrophilic resins such as cellophane, modified cellulose, gelatin, chitosan, polyvinyl alcohol, polyethylene oxide, and sodium polyacrylate. .

The antibacterial resin composition of the present invention can be obtained by mixing a conventionally known resin used as a masterbatch or compound, an inorganic powder antibacterial agent and a white powder pigment. After mixing, heat may be applied to melt, knead, cool, or chip at 150 to 280 ° C., for example. In order to manufacture a resin molded product, the chip may be processed again by various molding methods. that time,
For the purpose of imparting stability and properties of the resin composition, a stabilizer, an antioxidant, a dispersant, a lubricant, a flame retardant, an antistatic agent and the like may be added.

[0009]

According to the antibacterial resin composition of the present invention, discoloration and deterioration of physical properties of the resin over time due to silver are effectively suppressed, and the discoloration is not felt in appearance (visual observation).

[0010]

The present invention will be described in more detail with reference to the following examples. Examples 1 to 7 and Comparative Examples 1 to 4 A white powder pigment was added to a resin composition composed of an inorganic powder antibacterial agent containing various silver ions and a resin to prepare an injection molded product. As comparative examples, those containing no white pigment and those containing titanium oxide were also prepared. Each composition is shown in Table 1.

Test Example 1 (Discoloration evaluation test) The resin molded products (50 × 75 ×
3 mm) immediately after molding and after the following treatment A or treatment B, each color value of the L ^* -a ^* -b ^* color system was measured, and the color difference was determined. Generally, it is said that a color difference of 3.0 or more allows the color difference to be recognized with the naked eye. Treatment A Two ultraviolet lamps (20W) at a distance of 10cm and 1000
Irradiated for hours. Treatment B It was immersed in hot water adjusted to 75 ° C. for 1000 hours. Table 2 shows the results.

Test Example 2 (Evaluation test of antibacterial activity) 1 ml of a 10 ⁵ / ml Staphylococcus aureus solution was dropped on the sample treated in Test Example 1 and the sample not treated with the same,
C. for 24 hours. The bacterial solution after the culture was collected, and the number of viable bacteria in the solution was measured. Table 3 shows the results.

[0013]

[Table 1] Table 1 ────────────────────────────────── No. Silver ion-containing inorganic powder Resin antibacterial agent (parts by weight) Type (parts by weight) Example 1 2.5% zeolite silver (0.5) PP, Mitsui Petrochemical J700 (98) Example 2 〃 (1.0) 〃 (98) Example 3 Silver 1.2% AAS (1.5) 〃 (97) Example 4 Silver 1.5% zirconium phosphate (1.5) 〃 (98) Example 5 〃 (3.7) ABS, Denka GR2000 (93) Example 6 2.5% silver zeolite (0.8) POM, polyplastic M90-36 (98) Example 7 (4.0) (93) Comparative Example 1 2.5% silver zeolite (1.0) PP, Mitsui Petrochemical J700 (98) Comparative Example 2 Silver 2.5% zeolite (1.0) PP, Mitsui Petrochemical J700 (98) Comparative Example 3 Silver 1.5% zirconium phosphate (3.7) ABS, Denka GR2000 (93) Comparative Example 4 Silver 1.5% phosphorus Zirconium phosphate (3.7) ABS, Denka GR2000 (93)

[0014]

[Table 2] Table 1 (continued) ───────────────────────────────── No. White powder Powder type (parts by weight) Particle size Specific surface area Example 1 Zinc oxide (1.5) 0.3μ 18 m ² / g Example 2 Calcium silicate (1.0) 1.0 10 Example 3 Zinc silicate (1.5) 0.4 22 Example 4 Barium sulfate (0.5) 0.7 8 Example 5 Zinc oxide (3.3) 0.3 18 Example 6 Calcium oxide (1.2) 1.2 8 Example 7 Calcium sulfate (3.0 1.5 14 Comparative Example 1 None Comparative Example 2 Titanium oxide (1.0) 0.3 10 Comparative Example 3 None Comparative Example 4 Titanium oxide (3.3) 0.3 10

[0015]

[Table 3] Table 2 No. Color difference Antibacterial (microbial count) treatment A treatment B treatment A treatment B Example 1 0.2 0.3 00 Example 2 0.3 0.1 00 Example 3 0.4 0.3 00 Implementation Example 4 0.2 0.2 00 Example 5 0.6 0.4 00 Example 6 0.3 0.2 00 Example 7 0.6 0.6 00 Comparative Example 1 4.6 3 0.70 0 Comparative Example 2 3.5 3.2 0 0 Comparative Example 3 12.6 10.3 2.1 × 10 ² 6.0 × 10 ² Comparative Example 4 8.3 6.7 8.0 × 10 8.0 × 10

From Tables 1 and 2, it can be seen that in Examples 1 to 7 using the specific white powder pigment of the present invention, the color change due to light and heat is extremely small and cannot be recognized by the naked eye (color difference: 0. Comparative Examples 1 and 3 containing no specific white powder pigment of the present invention, and Comparative Examples 2 and 4 containing pigments other than the white pigment of the present invention (titanium oxide).
The color change was large due to light and heat, and the color was clearly recognizable to the naked eye (color difference: 3.2 to 12.6).

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 23/12 C08L 23/12 55/02 55/02 // C08L 9/06 9/06

Claims (3)

[Claims] 1. A resin composition containing an inorganic powder antibacterial agent containing silver ions, comprising barium sulfate, calcium oxide, calcium silicate, calcium sulfate, zinc oxide,
And an antibacterial resin composition containing at least one white powder pigment selected from the group consisting of zinc silicate and zinc silicate. 2. The antibacterial resin composition according to claim 1, wherein the white powder pigment has a particle size of 1 μm or less and a specific surface area of 8 m ² / g or more. 3. A molded article obtained by using the antibacterial resin composition according to claim 1.