JPH1095924A - Antibacterial resin composition having light-transmitting property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition preventing a loss of light- transmitting property by making a particle diameter of an antibacterial material comprising of a glass particle carrying an antibacterial metal within a specific range and making a difference of refractive index between the antibacterial material and a transparent resin material small. SOLUTION: This antibacterial resin composition is obtained by compounding (A) an antibacterial material carrying a metal (preferably silver) having antibacterial property on a glass particle into (B) a transparent resin material (e.g. an acrylic resin material) and making a particle diameter of the component A as 5-20μm and a difference of refractive index between the components A and B <=0.2, preferably <=0.02. The refractive index of the component A can be approached to the refractive index of the component B by adjusting e.g. a composition of the glass particle, i.e., a compositional ratio of soda, silica and alumina, etc. Preferably, a compounding amount of the component A is 0.3-0.7 pt.wt. to 100 pts.wt. of the component B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention has an object to prevent the light transmittance from being impaired when an antibacterial material is added to a resin composition comprising a transparent resin material.

[0002]

2. Description of the Related Art Transparent resin materials are used as a raw material for producing transparent resin products such as faucet handles and counters.
Alternatively, it is widely used as a raw material for a transparent gel coat layer covering the surface of artificial marble products such as bathtubs, and as a molding material for a transparent resin molded product such as a transparent bulk molding compound (BMC).

[0003]

By the way, in order to impart antibacterial properties to a resin product, an antibacterial material is blended with the resin material. However, when the antibacterial material is blended with the transparent resin material, the translucency becomes poor. There is a problem that the desired aesthetic appearance cannot be obtained.

[0004]

SUMMARY OF THE INVENTION The present invention provides a means for preventing the translucency of a resin composition from being impaired when an antibacterial material is added to a transparent resin material. The feature is that in a resin composition in which an antibacterial material obtained by supporting a metal having antibacterial properties on glass particles is mixed with a transparent resin material, the particle size of the antibacterial material is in a range of 5 to 20 μm, and The difference lies in that the refractive index difference between the antibacterial material and the resin material is set to 0.2 or less.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The type of transparent resin material used in the resin composition according to the present invention is not particularly limited,
An acrylic resin or an unsaturated polyester resin may be appropriately selected depending on the application. Applications requiring translucency include faucet handles, shelf boards, partition boards, counters, artificial marble bathtubs, gel coat layers on counter surfaces, and transparent BMC.

The antibacterial material to be added to the resin material is a material in which glass particles carry a metal having antibacterial properties such as silver, copper, zinc, and titanium, and the particle size is in the range of 5 to 20 μm. The difference in refractive index between the antibacterial material and the resin material is set to 0.2 or less. Actually, it is desirable to use silver having the strongest antibacterial activity among the metals.

When the particle size of the antibacterial material is less than 5 μm, it is difficult to uniformly disperse the antibacterial material in the resin material. Conversely, when the particle size exceeds 20 μm, not only does the light transmittance of the resin composition deteriorate, but also the specific surface area per unit volume decreases, so that the antibacterial performance with respect to the blending amount decreases. Therefore, the particle size of the antibacterial material is preferably set in the range of 5 to 20 μm. The particle size can be adjusted by a sizing operation.

When an antimicrobial material is blended with a transparent resin material, the antimicrobial material and the resin material usually have different refractive indices, so that the antimicrobial material causes irregular reflection and lowers the light transmittance. Therefore, in the present invention, the difference in the refractive index between the antibacterial material and the resin material is set to 0.2 or less, preferably 0.1 or less, and optimally 0.02 or less, so that the reduction of the light transmittance is within an allowable range. Can be suppressed. The refractive index of the antibacterial material can be made close to the refractive index of the resin material by adjusting the composition of the glass particles, that is, the component ratio of soda, silica, alumina and the like. The amount of the antibacterial material is desirably 1.5 parts by weight or less, and optimally 0.7 parts by weight or less based on 100 parts by weight of the resin material. However, in order to ensure the required antibacterial performance, the amount of the antibacterial material is preferably 0.3 parts by weight or more.

Examples The present inventors obtained a resin composition by blending a transparent acrylic resin material with an antibacterial material comprising silver supported on glass particles, and obtained a resin composition by injection molding using the resin composition. A resin molded body having a light transmitting property was manufactured by the method, and a test for examining the light transmittance was performed. In the test, A: changes in the light transmittance of the resin molded article when the refractive index n _{1 of the} antibacterial material is different, and B: changes in the light transmittance of the resin molded article when the particle size of the antibacterial material is different. It is a thing.

The light transmittance was measured using a direct reading haze computer (HGM2DP manufactured by Suga Test Instruments Co., Ltd.).

The refractive index n ₀ of the acrylic resin to be tested is 1.49, and the blending amount of the antibacterial material with respect to 100 parts by weight of the resin material is 0.2 part by weight.

The particle size of the antibacterial material in Test A was 7 μm.
m, the refractive index of the antibacterial material in Test B was 1.52, and the difference from the refractive index of the acrylic resin was 0.03. The light transmittance of the resin molded article manufactured without blending the antibacterial material is 9
It was 9.4%. The test results are shown in Tables 1 and 2, respectively.

[0013]

[Table 1]

[0014]

[Table 2]

FIG. 1 is a graph showing the relationship between the difference in the refractive index between the antibacterial material and the resin material and the light transmittance of the resin molded article based on the test results in Table 1. From this graph, if the difference in refractive index between the antibacterial material and the resin material is 0.2 or less,
It can be seen that the degree of decrease in light transmittance can be suppressed to such a level that practically causes no problem.

FIG. 2 is a graph showing the relationship between the particle size of the antibacterial material and the light transmittance of the resin molded article based on the test results in Table 2. From the graph, it can be seen that if the particle size of the antibacterial material is in the range of 5 to 20 μm, the degree of decrease in the light transmittance of the resin molded product does not pose any practical problem.

[0017]

In the resin composition according to the present invention, the antibacterial material to be mixed with the transparent resin material has a particle size in the range of 5 to 20 μm and a difference in refractive index from the resin material is 0.2 or less. By setting to, it is possible to suppress a decrease in the light transmittance of the resin molded product or the resin product having a light transmitting property to an extent that there is no practical problem. Therefore, the present invention makes it possible to simultaneously impart light-transmitting properties and antibacterial properties, which were conventionally considered difficult.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the difference in the refractive index between an antibacterial material and a resin material and the light transmittance of a resin molded product.

FIG. 2 is a graph showing the relationship between the particle size of an antibacterial material and the light transmittance of a resin molded product.

Claims (1)

[Claims] 1. A resin composition in which an antibacterial material obtained by supporting a metal having antibacterial properties on glass particles is blended with a transparent resin material, wherein the antibacterial material has a particle size in the range of 5 to 20 μm. A light-transmitting antibacterial resin composition, wherein a difference in refractive index between the antibacterial material and the resin material is set to 0.2 or less.