JPH04270742A - Antimicrobial polyolefinic resin composition - Google Patents

Abstract

PURPOSE:To obtain an antimicrobial polyolefinic resin composition having excellent mildewproofing and antimicrobial properties against a wide range of molds and bacteria by blending a polyolefinic resin with two or more compounding agents selected from specific compounding agents. CONSTITUTION:(A) 100 pts.wt. polyolefinic resin, preferably block copolymer of preferably propylene and another olefin is blended with (B) 0.01-20 pts.wt., preferably 0.05-2 pts.wt. two or more compounding agents selected from 2-(4- thiazolyl)benzimidazole, tetrachloroisophthalonitrile, 2-pyridinethiol-1-oxide, a metallic salt thereof and 2,3,5,6-tetrachloro4-(methylsulfonyl)benzimidazole, preferably 2-(4-thiazolyl)benzimidazole and 0.01-20 pts.wt., preferably 0.05-2 pts.wt. zinc salt of 2-pyridinethiol-1-oxide and optionally other compounding agents (e.g. plasticizer, stabilizer or filler) to give the objective antimicrobial composition suitable for internal parts of refrigerator, kitchen utensils, etc.

Description

Description: [0001] The present invention relates to a polyolefin resin composition having excellent antibacterial and antifungal properties. [Prior Art and Problems to be Solved by the Invention] In recent years, with the increase in the number of highly air-tight houses and apartments and the spread of heating in line with the improvement of living standards, mold damage in houses has rapidly increased. There is. There has been a significant increase in the number of food containers, household goods, electrical appliances, etc. made of polyolefin resins used in such environments that are required to have antifungal and antibacterial properties. In general, resins such as polypropylene resin and polyethylene resin are relatively resistant to mold and bacteria, but the stabilizers added to these resins serve as a nutrient source for mold, and dirt attached to the surface of polyolefin resin compositions can Since it serves as a nutritional source for mold and bacteria, there is always the problem of the growth of mold and bacteria. These molds not only spoil the aesthetics, but also cause serious social problems such as childhood bronchial asthma caused by mold spores, atopic skin disease and other allergic symptoms caused by mites that feed on the molds. It is very important to prevent mold and bacteria from growing and propagating in polyolefin resin compositions. Furthermore, in these applications, there are many opportunities for direct contact with the human body, so a high level of safety for humans and animals is required, but it goes without saying that reliable and long-term effective effects are expected. Means for Solving the Problems The present invention solves the problems of the conventional techniques as described above by selectively blending specific ingredients into polyolefin resin, thereby eliminating a wide range of molds, molds, etc.
We have discovered a polyolefin resin composition that exhibits excellent antibacterial and antifungal properties against bacteria. That is, the present invention provides polyolefin resin with 2-(4-thiazolyl)benzimidazole, tetrachloroisophthalonitrile, 2-pyridinethiol-1-oxide or a metal salt thereof, 2,3
, 5,6-tetrachloro-4(methylsulfonyl)pyridine. The present invention will be explained in detail below. The polyolefin resins used in the present invention include polystyrene, polypropylene, polyethylene, polybutene-1, polyacrylonitrile, nylon, polyvinyl alcohol, polycarbonate, AS resin, ABS resin, etc., and monopolymers of olefins as well as random and block polymers thereof. It is a copolymer. Moreover, plasticizers, stabilizers, antioxidants, flame retardants, foaming agents, colorants, fillers, antistatic agents, lubricants, crosslinking agents, etc. may be added to these polyolefin resins as necessary. Particularly preferred polyolefin resins are block copolymers of propylene and other olefins. The compounding ingredients used in the antibacterial polyolefin resin composition of the present invention include 2-(4-thiazolyl)benzimidazole, tetrachloroisophthalonitrile,
2-pyridinethiol-1-oxide or its metal salt,
2,3,5,6-tetrachloro-4(methylsulfonyl)pyridine, and by blending two or more selected from these, excellent antibacterial and antifungal properties can be obtained. For example, 2-(4-thiazolyl)benzimidazole, which is used as one of the components of the composition of the present invention, has been recognized to have a growth-inhibiting effect on many molds; Not sufficiently effective against common bacteria. Also, 2, 3, 5, 6-
Tetrachloro-4(methylsulfonyl)pyridine is
Although it has antibacterial and antifungal properties, it does not show sufficient effects against all the various types of mold that occur in the home environment when used alone. As described above, each of the components of the composition of the present invention cannot exert a complete effect against bacteria and fungi by itself, but by combining two or more of them, the shortcomings of the functions and effects of each component can be compensated for. They mutually strengthen each other and exhibit excellent antibacterial and antifungal effects against a wide variety of bacteria and molds. These components are chemically stable at typical molding temperatures for polyolefin resins, and exhibit excellent antibacterial and antifungal effects at low concentrations. Most preferred is a combination of the two zinc salts of 2-(-4-thiazolyl)-benzimidazole and 2-pyridinethiol-1-oxide, which are effective against a wide range of bacteria and fungi. [0005] The amount of each component added to the polyolefin resin composition is 0.01 to 20 parts by weight, preferably 0.05 to 20 parts by weight, per 100 parts by weight of the polyolefin resin.
2 parts by weight. The amount of each component added is as described above, but if the amount added is less than the lower limit, the desired effect will not be achieved, and if it exceeds the upper limit, it will bleed and blow out in powder form on the surface of the polyolefin resin composition. , especially when processing with an injection molding machine, it will contaminate the mold and cause the surface of the molded product to lose its luster. The antibacterial polyolefin resin composition of the present invention is compounded and kneaded using a conventional mixing device such as a Henschel mixer, a ribbon blender, or a Banbury mixer, and made into pellets using an extrusion molding machine.
It is generally processed using a compression molding machine, a three-roll molding machine, an injection blow molding machine, or the like. Alternatively, molding can be carried out by preparing a master batch containing the blend of the present invention at a high concentration and adding this to other pellets during molding. Applications of the antibacterial polyolefin resin composition of the present invention are not limited as long as they require antifungal and antibacterial effects, but examples include washing machines and their parts, interior parts of refrigerators, other household appliances, trash cans, etc. Applications include sink corners, kitchen utensils, bathroom utensils, and heat sinks for air conditioners. [Example] MFR is 9 g/10 min (230°C, 2160
The formulation shown in Table 1 was added to 100 parts by weight of a propylene homopolymer (g load), thoroughly mixed in a Henschel mixer, kneaded for 10 minutes with a mixing roll adjusted to 230°C, and then mixed in a press adjusted to 220°C. 1100 with molding machine
A pressure of kg/cm2 was applied for 7 minutes to form a polypropylene sheet with a thickness of 2 mm. Example 1 A polypropylene sheet formed by the above method with the formulation shown in Table 1 was cut into 5 cm square pieces, placed on a potato dextrose plate agar medium, and then a glucose peptone liquid medium containing the following fungal spores suspended therein was placed on top of the potato dextrose plate agar medium. Spray the entire surface of the sheet,
The cells were cultured at 28°C for 28 days. The antifungal performance of each sheet was evaluated using the following evaluation criteria. The results are shown in Table 2. [Table 1] [Table 2] [Test mold] Aspergi
llus niger Penicillium c
itrinumChaetomium globos
umAureobasidium pullulan
sGliocladium virens <Evaluation Criteria> 0: No mold growth observed on the entire surface of the sample. 1...Mold growth was observed on less than 1/4 of the sample surface. 2...Mold growth was observed on 1/4 or more of the sample surface. Example 2 A polypropylene sheet formed by the above method using the formulation shown in Table 1 was cut into 3 cm square pieces, and physiological saline in which the following bacteria were suspended was uniformly sprayed onto the surface of the sheet, and the sheets were heated at 90% humidity and 28°C. After 0, 7, and 24 hours of culturing, the sheet was shaken in 30 ml of sterile water and the number of bacteria was measured. The measurement results are shown in Table 3. [Table 3] <Test bacteria> Escherichia coli Staphylococcus aureus 00
13] Example 3 A polypropylene sheet molded by the above method using the formulation shown in Table 1 was cut into 10 cm square pieces, five of each were pasted side by side on a kitchen sink, and observed for 6 months. As for the results, five samples each were evaluated using the following evaluation criteria, and the averages are shown in Table 4. <Evaluation Criteria> 0: No biological stains (slimy) observed on the entire surface of the sample. 1: Biological stains were observed on less than 1/4 of the surface of the sample. 2...Stains caused by living organisms were observed on 1/4 or more surfaces but less than 1/2 of the sample.3...Stains caused by living organisms were observed on 1/2 or more surfaces of the sample. [Table 4] Effects of the Invention: By using two or more of the components of the present invention in combination, superior antibacterial and antifungal effects are exhibited against a wider range of molds and bacteria than when each component is used alone.

Claims (1)

[Claims] Claim 1: A polyolefin resin containing 2-(4-thiazolyl)benzimidazole, tetrachloroisophthalonitrile, 2-pyridinethiol-1-oxide or a metal salt thereof, 2,3,5,6-tetrachloro-4 An antibacterial polyolefin resin composition comprising two or more compounding agents selected from (methylsulfonyl)pyridine.