JP2007287683A - Insulating part for electrical cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrical cable in which there is no concern for the occurrence of surface defects due to the deterioration of such properties as mechanical strength, electrical properties, and especially tracking resistance caused by the breeding of fungi, bacteria and algae, without the occurrence of deterioration of such the properties in the organic polymer material. <P>SOLUTION: This insulator for an electrical cable is obtained by forming a resin composition (resin composition C) by adding methyl (benzimidazol-2-yl) carbamate (antifungal agent B1) 0.03-9.5 pts.mass, diiodemethyl-p-tolylsulfone (antifungal agent B2) 5×10<SP>-6</SP>to 3.0 pts.mass, 2-thiazolyl-1H-benzimidazol (antifungal agent B3) 5×10<SP>-6</SP>to 3.0 pts.mass, and an antifungal agent (mixture antifungal agent B) which consists of antifungal agents of B1, B2 and B3, and whose total mass is 0.05-10 pts.mass into an ethylene-based copolymer and/or a thermoplastic resin (thermoplastic resin A) containing silicone rubber, 100 pts.mass. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrical cable insulation part, an electrical cable terminal insulation part, an electrical cable attachment insulation part (insulator, spacer, etc.) and the like that can be used.

(1) Use of porcelain in electrical cable insulation parts Conventionally, insulators, insulator tubes, lightning arresters, interphase spacers, bushings, indoor / outdoor termination connection parts, branch connection parts, used for power transmission, substation, and power distribution, Electrical insulation structural parts made of porcelain that are not easily deteriorated are used as electrical cable insulation parts that can be used for cable connection and terminal parts such as straight connection parts.
However, because porcelain has a large specific gravity and the porcelain itself is heavy, if it is used as a wire support insulator or spacer, the strength of the steel tower is limited, and there is a limit to the miniaturization of the supporting member. In addition, there is a problem that the space occupied by the parts for power distribution and distribution can be prevented from being made compact and the aesthetic appearance is impaired.
In addition, when a tracking phenomenon (a phenomenon in which a leakage path occurs on the surface of an insulator) occurs, various problems arise because the porcelain itself has a hard and brittle nature. For example, if an air flash occurs outside the insulator, the insulator shade breaks due to the impact of electrical energy, and the parts fall from the tower.
Similarly, in an insulator tube with a built-in arrester element, penetration of the element occurs when absorbing an excessive lightning surge, or the air in the gap between the element and the insulator tube expands and explodes due to the energy of flashing outside the element. As a result, there is a problem that the pipe is scattered.

(2) Use of organic polymer material From such a background, ethylene-propylene-diene terpolymer (EPDM) and ethylene-propylene copolymer, which are relatively high in impact resistance and lightweight as an alternative to porcelain, are used. (EPM), ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA), high molecular organic compounds such as silicone rubber (hereinafter, these high molecular organic compounds are referred to as organic polymer materials). Is being used for structural parts of each part of the insulator.
From the viewpoint of the solid-liquid type, the silicone rubber is classified into a millable silicone rubber and a liquid silicone rubber that can be kneaded. In this case, the polymerization degree of the raw material polymer used is about 5,000 to 10,000 for the millable rubber, whereas the liquid rubber has a lower polymerization degree.
The millable rubber is sometimes referred to as HCR (High Consistency Rubber) in the sense that the viscosity is high. In this case, the liquid silicone rubber is referred to as LCR (Low Consistency Rubber).

(3) Mold generation when using organic polymer materials However, organic polymer materials may have fungal fungi (mold, moss), bacteria (bacteria), and algae due to their characteristics. In particular, when these fungi or the like enter the inside thereof, the mechanical strength, particularly properties such as hardness, tensile strength, tear strength and the like may be lowered.
In general, most of organic polymer materials are mostly composed of carbon and oxygen, so that fungi (mold, moss), bacteria (bacteria), and algae are easy to reproduce, especially EPDM, EPM, EVA, EEA. Since the surface of the resin has poor water repellency, when exposed to the outdoors for a long period of time, pollutants are likely to adhere, and an environment in which fungi and bacteria are likely to grow is likely to occur. On the other hand, since the low molecular weight silicone covering the surface of silicone rubber encloses deposits such as dust and forms a contaminated layer on the surface, nutrients suitable for the growth of fungi, bacteria and algae are accumulated. As a result, the reproduction of fungi, bacteria, and algae is promoted in the same manner as EPDM, EPM, EVA, and EEA resins.

(4) Use of fungicides Antibacterial metals and their compounds, urea compounds, organotin compounds, phenol derivatives, organocopper compounds, quinones as fungicides that can be used in organic polymer materials for outdoor insulation Compounds, imidazole compounds, thiazoline compounds, aliphatic imide compounds, and the like are known (see Patent Document 1).
Patent Document 2 discloses an industrial fungicide composition comprising diiodomethyl paratolyl sulfone and a zinc salt of pyridinethiol-1-oxide as active ingredients.
Patent Document 3 includes 2,3,5,6-tetrachloro-4- (methylsulfonyl) pyridine, 2,4,5,6-tetrachloroisophthalyl, 1,2-benzisothiazolone, 2-methoxycarbonylamino. A steel sheet having a precoat film containing an antibacterial and antifungal agent composed of benzimidazole and diiodomethylparatolylsulfone is disclosed.

JP-A-9-176495 Japanese Patent Laid-Open No. 7-17809 Japanese Patent Laid-Open No. 11-276985

When the fungicides are used in organic polymer materials, certain fungi (fungi, moss), bacteria (bacteria), and algae are effective, but depending on the type of these fungi (mold, moss) In some cases, the effect is insufficient, and those having sufficient effects in mechanical strength, tracking resistance and the like have not been known.
In many cases, metal hydrates are added to insulators and cable connection parts used outdoors for adding tracking resistance. However, if the tracking resistance of the organic polymer material itself is reduced, high The life of voltage equipment can be greatly affected by unpredictable environmental factors.
In general, many organic antibacterial and antifungal agents are composed of compounds containing sulfur and nitrogen. The curing reaction (crosslinking reaction) for curing the organic polymer material can be roughly divided into a radical reaction by an organic peroxide, an addition reaction by a catalyst such as a platinum compound, and a condensation reaction by hydrolysis. This addition reaction is generally used for liquid silicone rubber. However, when a platinum compound catalyst is used, a phenomenon that inhibits curing occurs for compounds containing sulfur, phosphorus, nitrogen, tin, etc., resulting in moldability. May have an impact.
The present invention provides insulation for electrical cables that maintains the mechanical strength and electrical properties of organic polymer materials, in particular, tracking resistance, and does not have concerns about surface defects due to the deterioration of these properties due to the growth of fungi, bacteria, and algae. The purpose is to provide parts.

As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by blending three specific types of antifungal agents as organic polymer materials, and have completed the present invention.
That is, the present invention relates to (1) 100 parts by mass of a thermoplastic resin (thermoplastic resin A) containing an ethylene copolymer and / or silicone rubber, and methyl (benzimidazol-2-yl) carbamate (antifungal agent B1). ) 0.03 to 9.5 parts by mass, diiodomethylparatolylsulfone (antifungal agent B2) 5 × 10 −6 to 3.0 parts by mass, and 2-thiazolyl-1H-benzimidazole (antifungal agent B3) An antifungal agent (mixed antifungal agent B) consisting of 5 × 10 −6 to 3.0 parts by mass and having a total mass of antifungal agents B1, B2 and B3 of 0.05 to 10 parts by mass was contained. Insulating parts for electric cables obtained by molding a resin composition (resin composition C), and (2) 100 parts by mass of a thermoplastic resin (thermoplastic resin A) containing an ethylene copolymer and / or silicone rubber , Methyl ( Benzimidazol-2-yl) carbamate (antifungal agent B1) 5 × 10 −6 to 3.0 parts by mass, diiodomethylparatolylsulfone (proofing agent B2) 0.03 to 9.5 parts by mass, And 2-thiazolyl-1H-benzimidazole (antifungal agent B3) 5 × 10 −6 to 3.0 parts by mass, and the total mass of the antifungal agents B1, B2 and B3 is 0.05 to 10 parts by mass. It is invention regarding the insulation component for electric cables obtained by shape | molding the resin composition (resin composition C) containing the anti-mold agent (mixed anti-mold agent B) which is.

In the present invention, the following aspects (3) and (4) can be further provided.
(3) The ethylene copolymer in the above (1) or (2) is an ethylene-propylene-diene terpolymer (EPDM), an ethylene-propylene copolymer (EPM), an ethylene-vinyl acetate copolymer ( One or more selected from EVA) and an ethylene-ethyl acrylate copolymer (EEA).
(4) The silicone rubber in (1) or (2) is an addition reaction type silicone rubber.

  The present invention also provides an electrical cable connecting insulation component, an electrical cable terminal insulation component, and an electrical cable attachment insulation component (insulator) obtained by using the electrical cable insulation component described in (1) to (4) above. , Spacers, etc.).

Insulating parts for electric cables according to the present invention are effective in maintaining the mechanical strength and electrical properties of organic polymer materials, particularly tracking resistance, and effectively eliminating surface defects due to the deterioration of these properties due to the growth of fungi and bacterial algae. Can be prevented. Moreover, even if the mixed antifungal agent of the present invention containing sulfur and nitrogen compounds is blended with the liquid silicone rubber obtained by using a platinum compound catalyst as an addition reaction catalyst as an organic polymer material, it is possible to avoid curing inhibition phenomenon. It becomes possible, and good moldability can be obtained.
Since the mixed antifungal agent of the present invention also has antibacterial and algal control effects as well as antifungal, it can effectively prevent the growth and reproduction of fungi (mold, moss), bacteria (bacteria), and algae.

  Insulating parts for electric cables of the present invention include 100 parts by mass of a thermoplastic resin (thermoplastic resin A) containing an ethylene copolymer and / or silicone rubber, and methyl (benzimidazol-2-yl) carbamate (an antifungal agent). B1) 0.03 to 9.5 parts by mass, diiodomethylparatolylsulfone (antifungal agent B2) 5 × 10 −6 to 3.0 parts by mass, and 2-thiazolyl-1H-benzimidazole (antifungal agent B3) ) An antifungal agent (mixed antifungal agent B) consisting of 5 × 10 −6 to 3.0 parts by mass and having a total mass of antifungal agents B1, B2 and B3 of 0.05 to 10 parts by mass The resin composition (resin composition C) and 100 parts by mass of a thermoplastic resin (thermoplastic resin A) containing an ethylene copolymer and / or silicone rubber were mixed with methyl (benzimidazol-2-yl) carba Mate (antifungal agent B1) 5 × 10 −6 to 3.0 parts by mass, diiodomethylparatolylsulfone (preventive agent B2) 0.03 to 9.5 parts by mass, and 2-thiazolyl-1H-base Antifungal agent (mixed antibacterial agent) consisting of 5 × 10 −6 to 3.0 parts by mass of mold imidazole (antifungal agent B3) and having a total mass of antifungal agents B1, B2 and B3 of 0.05 to 10 parts by mass It is obtained by molding a resin composition (resin composition C) containing mold agent B).

Hereinafter, the resin composition C of the present invention will be described in detail.
(1) Thermoplastic resin A
As the thermoplastic resin A, which is an organic polymer material used in the production of the insulating part for electric cables of the present invention, a commonly used electrically insulating polymer material such as an ethylene copolymer and / or silicone rubber is used. be able to. Of these, ethylene-propylene-diene terpolymer (EPDM), ethylene-propylene copolymer (EPM), ethylene-methyl methacrylate copolymer (EMMA), ethylene-methyl are used as the ethylene copolymer. Acrylate copolymer (EMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-vinyl acetate copolymer (EVA), copolymer of ethylene and α-olefin having 4 to 20 carbon atoms, maleic acid graft Examples thereof include an ethylene-methyl acrylate copolymer, a maleic acid grafted ethylene-vinyl acetate copolymer, an ethylene-maleic anhydride copolymer, and an ethylene-ethyl acrylate-maleic anhydride copolymer.
In particular, when high tracking resistance is required as an insulating part for electric cables, ethylene-propylene-diene terpolymer (EPDM), ethylene-propylene copolymer (EPM) are used as ethylene-based copolymers. , Ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA), and silicone rubber are preferably used.
As the silicone rubber, polyorganosiloxane in which at least two organic groups bonded to silicon atoms in one molecule are alkenyl groups such as vinyl, propenyl, butenyl, hexenyl and the like is used. Among these polysiloxanes, those having a vinyl group are preferable because the raw materials can be easily obtained and synthesized.

When an ethylene copolymer is used as the organic polymer material, an organic peroxide is usually used as a crosslinking agent. Organic peroxides include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, dicumyl peroxide, cumyl-t-butyl peroxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexane It is desirable to use di-t-butyl peroxide.
It is preferable that the compounding quantity is 0.05-15 mass parts with respect to 100 mass parts of resin.

  When polyorganosiloxane is used as the organic polymer material, (1) the same organic peroxide as in the case of the ethylene copolymer may be used for crosslinking by radical reaction (radical reaction type silicone rubber). ), (2) Crosslinking may be carried out by addition reaction using polyorganosiloxane having an average of more than 2 hydrogen atoms bonded to silicon atoms in one molecule (addition reaction type silicone rubber). It is preferable that the compounding quantity of the organic peroxide of (1) is 0.05-15 mass parts with respect to 100 mass parts of silicone rubber. The blending amount of the polyorganosiloxane (2) is preferably such that the hydrogen atoms bonded to silicon atoms in the polyorganosiloxane are 0.5 to 4 with respect to the alkenyl group 1 of the silicone rubber. In addition, platinum-based catalysts such as chloroplatinic acid, platinum olefin complexes, platinum vinylsiloxane complexes, platinum black, and platinum triphenylphosphine complexes are used as crosslinking catalysts. The blending amount of the crosslinking catalyst is preferably such that the platinum blending amount in the composition is in the range of 1 to 1000 ppm.

(2) Mixed antifungal agent B
The mixed antifungal agent B used in the resin composition C of the present invention contains at least methyl (benzimidazol-2-yl) carbamate [Methyl (benzimidazol-2-yl) carbamate], diiodomethylparatolylsulfone [Diiodomethyl-P]. -Tolyl-sulfone] and 2-thiazolyl-1H-benzimidazole [2-Thiazolyl-1H-benzimidazole]. An excellent antifungal, antibacterial and antialgal effect is manifested by blending the thermoplastic resin A with the mixed antifungal agent B containing these three components as essential components.
In the present invention, the antibacterial, antifungal and antialgal effects indicate that growth and reproduction of fungi (mold, moss), bacteria (bacteria), and algae can be effectively prevented.
The mixing ratio of the mixed antifungal agent B is 0.05 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic resin A.
If the blending amount of the mixed antifungal agent B is less than 0.05 parts by mass, the effect of inhibiting the growth of fungi, bacteria and algae is reduced. On the other hand, if it exceeds 10 parts by mass, the antifungal agent may leach on the surface. In addition, mechanical characteristics and electrical characteristics may be deteriorated, which is not preferable.

Moreover, the compounding of the mixed antifungal agent B is 0.03 to 9.5 parts by mass of methyl (benzimidazol-2-yl) carbamate (antifungal agent B1) with respect to 100 parts by mass of the thermoplastic resin A, diiodomethylparaffin. It consists of 5 × 10 −6 to 3.0 parts by mass of tolylsulfone (antifungal agent B2) and 5 × 10 −6 to 3.0 parts by mass of 2-thiazolyl-1H-benzimidazole (antifungal agent B3), and The total mass of the fungicides B1, B2 and B3 is 0.05 to 10 parts by mass, or 100 parts by mass of the thermoplastic resin A, and methyl (benzimidazol-2-yl) carbamate (antifungal agent B1) 5 × 10 −6 to 3.0 parts by mass, 0.03 to 9.5 parts by mass of diiodomethylparatolylsulfone (proofing agent B2), and 2-thiazolyl-1H-benzimidazole (antifungal agent B3) 5 × 10-6-3 It consists of zero parts by mass, and the total mass of the antifungal agent B1, B2 and B3 are 0.05 to 10 parts by weight.
In the mixed antifungal agent B, by using these three types of antifungal agents as essential components, the reason why the remarkable effects of the present invention are exhibited is not clear, but methyl (benzimidazol-2-yl) carbamate It is assumed that (antifungal agent B1) or diiodomethylparatolylsulfone (powerproofing agent B2) is the main component shown in the above range, and diiodomethylparatolylsulfone (powerproofing agent B2) or methyl (bennes), respectively. Imidazol-2-yl) carbamate (antifungal agent B1) and 2-thiazolyl-1H-benzimidazole are mixed in relatively small amounts to achieve a balanced performance for antibacterial, antifungal and antialgal effects. It seems to do.
Further, the mixed antifungal agent B can use an organic solvent corresponding to the fourth class hazardous material or an inorganic solvent such as water as a carrier. By using a carrier, it becomes possible to make the compounding of the fungicide into the resin more uniform. Examples of the organic solvent include epoxidized soybean oil, bis (2-ethylhexyl) phthalate, diisodecyl phthalate, propylene glycol, methyl ethyl ketone, cyclohexanone, dimethyl silicone oil, and the like.
The mixed antifungal agent B may contain other antifungal agents as long as the properties of the present invention are not impaired.

(3) Additive In addition to the crosslinking agent for curing the resin, the resin composition C of the present invention may contain a metal hydrate, an antioxidant, a heat resistance improver, and the like as necessary. .
(3-1) Metal Hydrate In the case of an outdoor high-voltage device that requires a high degree of tracking resistance such as a insulator, it is preferable that a metal hydrate is blended with the thermoplastic resin A. Examples of the metal hydrate include aluminum hydroxide and magnesium hydroxide, and aluminum hydroxide is more preferable from the viewpoint of weather resistance. The compounding amount of the metal hydrate is preferably 10 to 150 parts by mass with respect to 100 parts by mass of the thermoplastic resin A. If the metal hydrate is less than 10 parts by mass, the effect of improving tracking resistance is small, and if it exceeds 150 parts by mass, the strength may decrease.

(3-2) Heat resistance improver In order to improve the heat resistance of the resin composition C of the present invention, the heat resistance improver was selected from carbon black, titanium oxide, iron oxide, and cerium-based metal oxide. One or more can be used.
The heat resistance improver is preferably added in an amount of 0.5 to 5 parts by mass with respect to 100 parts by mass of the thermoplastic resin A.
(3-3) Other additives The resin composition C of the present invention can be blended with an antioxidant, a processing stabilizer and the like within a range not impairing the characteristics of the present invention. Pigments such as zinc, clay, silica, calcium carbonate, processing stabilizers, fillers, and the like can be added.

(4) Others Insulation parts for electric cables according to the present invention can be used as (1) branch connection parts for outdoor and indoor (including underground), direct branch connection parts (both for power transmission and distribution), etc. (2) Insulation pipes (for power transmission and transformation) for outdoor and indoor (including underground), insulator type terminals (for power distribution), bushings (for power transmission and power distribution) (3) It can be used to insulate a conductor such as an electric wire from its support, and can be used for an insulating part attached to an electric cable such as a spacer.

The present invention will be specifically described below with reference to examples.
1. Organic polymer material, fungicide and other additives The organic polymer material, fungicide, crosslinking agent, metal hydrate, antioxidant and heat resistance improver used in the examples and comparative examples are as follows. It is.
(1) Organic polymer material (In Tables 1-5, it describes as a thermoplastic resin.)
(I) EPDM; manufactured by Nippon Synthetic Rubber Co., Ltd., trade name: JSR EP21
(Ii) EVA; Mitsui DuPont Polychemical Co., Ltd., trade name: EV360
(Iii) Radical reaction type silicone rubber; manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KE4603-U
(Iv) Addition reaction type silicone rubber; manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KE1990-50

(2) Antifungal agent The antifungal agent used is described below. The following (1) mixed antifungal agent is the antifungal agent used in the present invention.
(I) Mixed antifungal agent (antifungal agent a): 85% by mass of methyl (benzimidazol-2-yl) carbamate, 14.8% by mass of diiodomethylparatolylsulfone, and 2-thiazolyl-1H-benz A mixture of anti-fungal agents consisting of 0.2% by mass of imidazole was added to cyclohexanone so that the anti-fungal agent mixture: cyclohexanone = 26: 74 to prepare a mixed anti-mold agent.
(Ii) Silver based inorganic antifungal agent (antifungal agent b): Copper (II) Acetylacetonate (iii) Imidazole type antifungal agent (antifungal agent c): 2- (4-thiazolyl) -benzimidazole ( iv) Arsine fungicides (antifungal agent d): 10,10′-oxybisphenoxyarsine (3) Other additives (i) Crosslinker: 2,5-dimethyl-2,5-t-butyl peroxide Hexane, manufactured by Nippon Oil & Fats Co., Ltd. (ii) Metal hydrate: Aluminum hydroxide, manufactured by Showa Denko Co., Ltd., trade name: Heidilite H42M
(Iii) Antioxidant: Ouchi Shinsei (manufactured), trade name: NOCRACK 224
(Iv) Heat resistance improver: carbon black, manufactured by Asahi Carbon Co., Ltd., trade name: HAF carbon Asahi # 70

2. Evaluation Method The following evaluation methods were employed in the present examples and comparative examples.
(1) Mold resistance test JIS Z 2911 plastic product Conforms to Method B. In addition, although the fungi used for a test are 5 microbes by a JIS specification, in the present Example and the comparative example, 51 microbes containing JIS microbe were used for the purpose of the outstanding antifungal property and antibacterial property.
Direct inoculation (spray spraying) of test bacteria mixed spore suspension by dry-wet method, culture for 30 days at 30 ° C ± 5 ° C, 90% RH or more, and observed the growth of fungi and bacteria in the samples .
The results were observed visually and with a 50-fold actual microscope.
(I) Bacteria used in the mold resistance test 51 bacteria used in the mold resistance test are shown below.
Nigrosporalise, Cladosporium Resine, Cladosporium Herbalem, Cladosporium, Cladosporiaidas, Cladosporia saphaerosperma, Trichoderma Koningi, Trichodermapiridi, Foragromerate, Foraterethias, Pull Laria Pull Lance, Girio Cladum Virens, Geotricam Aactus, Geotricam Canditas, Pestarocia dasta, Pestarocia neglecta, Alternaria tenor, Arterinaria plus cola, Alternaria alternata, Aspergillus niger, Aspergillus flavus, Aspergillus ferricol, Aspergillus oryzae, Aspergillus terreus, Aspergillus femigatas, Aureobasidium pulllance, Fusarium monili Olme, fusarium semitactum, fusarium prarifertam, fusarium roseum, fusarium solani, fusarium oxysporum, lysopus niglycans, lysopus stronifel, penicillium citrinum, penicillium ikpansa, penicillium feniculosum, penicillium lira Shinam, Penicillium niglycans, Penicillium flectitas, Penicillium citrioviridi, Mucor racemasus, Eurotium tonaphyllum, Trichofeton mentagolphytes, Anavenus sp., Ketomium globosam, Shrimp Purple Sense, Acremonium Chalticola, Walemia Sebi, Cancida Albicans, Botrytis Cinerea, Proteus Valgaris.

(Ii) Growth inhibition zone “Growth inhibition zone” in the fungus resistance test in Tables 1 and 3-5 is a range where the effect around the sample due to antibacterial and antifungal component elution and exudation is seen, JIS Z2911 Plastic Product Test This is the width described when the growth inhibition band is observed around the sample in Method B.
(2) Tensile test In accordance with JIS K6251, tensile strength and elongation were measured using a test sheet having a thickness of 2 mm.
(3) Hardness test Based on JIS K6253, the type A durometer hardness was measured using a test sheet having a thickness of 6 mm.

(4) Tracking resistance test IEC Pubi. Based on the 587 inclined plate method, the measurement was performed using a test sheet having a size of 50 mm × 125 mm and a thickness of 6 mm. The test voltage was 3.5 kV.
(I) The time until the tracking trace arrived at a position 25 mm from the lower electrode was measured.
(Ii) A tracking resistance test for 6 hours was performed by the inclined plate method, and the time until tracking destruction was measured.
(Iii) It is determined that the tracking resistance is better as the tracking failure does not occur within 6 hours and the tracking trace reaches the position of 25 mm for a longer time.

[Examples 1 to 12, Comparative Examples 1 to 38]
An antifungal agent, a crosslinking agent, a filler, a processing stabilizer, an antioxidant, and a heat resistance improver were blended at a ratio shown in Tables 1 and 3 to 5 with respect to 100 parts by mass of the organic polymer material (organic polymer material 100 Number of parts by weight relative to parts by weight).
The addition reaction type silicone rubber is incorporated in a product as a composition component such as a polymer such as polydimethylsiloxane, a crosslinking agent and a platinum catalyst.
The resin composition was uniformly kneaded using an open roll machine and press molded at 160 ° C. to obtain a test sheet.
The addition reaction type silicone rubber was mixed with a stirrer, subjected to vacuum defoaming treatment, and press molded at 160 ° C. to obtain a test sheet.
The evaluation results are summarized and shown in Tables 1 and 3-5.

[Reference Examples 1 to 4]
In order to evaluate mechanical properties in Examples 1 to 12, experimental examples in which a fungicide was not added were described as Reference Examples 1 to 4. The experimental method is the same as in Examples 1 to 12 except that no fungicide is added. The results of Reference Examples 1 to 4 are collectively shown in Table 2.

From Comparative Examples 1 to 38 (Tables 3 to 5), growth and reproduction of fungi and bacteria were confirmed in the samples using the above fungicide b, c and d.
In Comparative Examples 18 and 37 using the antifungal agent d, a sufficient inhibitory effect was confirmed at 10 parts by mass of the antifungal agent, but the tracking resistance was lowered in the physical property evaluation.
In Comparative Example 31 in which the anti-mold agent c was added to the addition reaction type silicone rubber, curing failure occurred, and the original properties of the composition were not obtained in terms of tensile strength, elongation, and hardness.
That is, as compared with Reference Example 4, the elongation is about 3 times and the hardness is reduced by 14 points. As a result, the inhibition of curing occurs.
In Comparative Example 33, it was not possible to obtain a cured molded product by increasing the amount of the fungicide added to 10 parts by mass.

In the Example which mix | blended the antifungal agent a used by this invention with respect to the said result, although fungal growth was confirmed slightly in 0.05 mass part of antifungal agent compounding amount of Example 1, 4. No growth or reproduction of fungi or bacteria was observed in any of the organic polymer materials of EPDM, EVA, radical reaction type, and addition reaction type silicone rubber of other Examples 2, 3, and 5-12. In addition, the mechanical properties, tensile strength, elongation, and tracking resistance of Examples 1, 3, 4, 6, 7, 9, 10, and 12 have good characteristics.
In particular, in the silicone rubbers shown in Examples 7 to 12, fungi and bacteria did not grow or propagate even when the amount of the fungicide was 0.05 parts by mass.
Furthermore, in the resin composition in which the anti-mold agent a was added to the addition reaction type silicone rubber, the phenomenon of poor curing observed in Comparative Example 31 was not observed.

As described above in detail, the resin composition C using the mixed antifungal agent B of the present invention can be free from the effects of fungal and bacterial growth over a long period of time, and has good mechanical strength and tracking resistance. Can be maintained.
In addition to insulating parts for connecting electrical cables such as insulators for power transmission and distribution, insulating parts for electric cables that can be used for insulating parts for electric cable terminals, etc., insulators used to insulate conductors such as electric wires from their supports, When designing the insulation performance of electrical cable terminals such as spacers or accessory parts, environmental factors such as fungal and bacterial growth can be estimated to be extremely small when estimating the service life. In addition, it has great effects in terms of improving productivity and reducing manufacturing costs.

  Insulating parts for electrical cables of the present invention include electrical cable connection parts such as branch connection parts and direct branch connection parts, as well as insulator pipes (for power transmission and transformation), insulator type terminals (for power distribution), bushings (for power transmission, It is used to insulate conductors such as power distribution and transformation) from the support, and can be widely used for electric cable terminals such as spacers or accessory parts.

Claims (7)

  To 100 parts by mass of a thermoplastic resin (thermoplastic resin A) containing an ethylene copolymer and / or silicone rubber, 0.03 to 9.5 mass of methyl (benzimidazol-2-yl) carbamate (antifungal agent B1) Parts, diiodomethylparatolylsulfone (antifungal agent B2) 5 × 10 −6 to 3.0 parts by mass, and 2-thiazolyl-1H-benzimidazole (antifungal agent B3) 5 × 10 −6 to 3.0 Resin composition (resin composition C) comprising an antifungal agent (mixed antifungal agent B) consisting of parts by mass and having a total mass of antifungal agents B1, B2 and B3 of 0.05 to 10 parts by mass Insulation parts for electrical cables obtained by molding.   To 100 parts by mass of a thermoplastic resin (thermoplastic resin A) containing an ethylene copolymer and / or silicone rubber, methyl (benzimidazol-2-yl) carbamate (antifungal agent B1) 5 × 10 −6 to 3 0.0 part by mass, diiodomethylparatolylsulfone (antifungal agent B2) 0.03 to 9.5 parts by mass, and 2-thiazolyl-1H-benzimidazole (antifungal agent B3) 5 × 10 −6 to 3 Resin composition (resin composition) comprising an antifungal agent (mixed antifungal agent B) consisting of 0.0 part by mass and having a total mass of antifungal agents B1, B2 and B3 of 0.05 to 10 parts by mass Insulating parts for electric cables obtained by molding C).   The ethylene copolymer is an ethylene-propylene-diene terpolymer (EPDM), an ethylene-propylene copolymer (EPM), an ethylene-vinyl acetate copolymer (EVA), and an ethylene-ethyl acrylate copolymer ( The insulating part for an electric cable according to claim 1 or 2, wherein the insulating part is one or more selected from EEA).   The insulating part for an electric cable according to claim 1 or 2, wherein the silicone rubber is an addition reaction type silicone rubber.   An insulating part for connecting an electric cable obtained by using the insulating part for an electric cable according to claim 1.   The insulation component for electric cable terminals obtained using the insulation component for electric cables in any one of Claims 1 thru | or 4.   An insulating part for an electric cable obtained by using the insulating part for an electric cable according to any one of claims 1 to 4.