JP3159322B2 - Antimicrobial polyolefin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin composition having an antibacterial property, and particularly to a long-term weathering discoloration resistance, high temperature molding (for example, 23
(0 ° C. or higher), a polyolefin composition having antibacterial properties excellent in hue stability, heat stability and molding processing stability.

[0002]

2. Description of the Related Art Plastics have been generally considered to be a material having excellent resistance to microorganisms such as fungi (fungi) and bacteria. Cases of damage have been reported, and plastics with anti-mildew specifications are becoming available.

[0003] Further, plastic molded articles such as polyolefins are widely used for water supplies such as kitchen utensils, bath utensils, washing utensils, etc. However, since they often adhere to water, they are inevitably darkened by mold. There is a tendency, and it is desired to provide antibacterial properties to prevent this. Also in the fields of sanitary products, disposable diapers, medical supplies, etc., it is desired to impart antibacterial properties to prevent offensive odor and propagation of fungi (fungi) and bacteria.

In order to impart antibacterial properties, it is generally necessary to incorporate an antibacterial agent. As the antibacterial agent conventionally used, organometallic compounds containing no copper or tin (for example, 2- (4 -Thiazolyl) -benzimidazole (TBB)). However, the organic antibacterial agent has a problem that its antibacterial properties, durability, heat resistance, and safety are not sufficient.

[0005] Accordingly, studies on inorganic antibacterial agents suitable for blending into plastics have been actively conducted. For example, JP-A-62-241832 discloses a zeolite holding a metal having a bactericidal action as an inorganic antibacterial agent.

Japanese Patent Publication No. 63-28402 discloses an ion exchange adsorption of an alkaline earth metal carbonate and an antibacterial metal ion selected from silver ion, zinc ion, copper ion or a mixture thereof. An antibacterial composition suitable for water treatment comprising a molded product of a mixture with zeolite has been proposed.

[0007] It has been recognized that the incorporation of such a zeolite-based antibacterial agent into a polyolefin improves the antibacterial properties of the polyolefin. However, some polyolefins turn yellow due to the addition of antibacterial agents,
In addition, it was found that even if it did not turn yellow, the resulting molded product was remarkably inferior in weathering discoloration resistance, so that there were some that discolored with use. After examining what kind of polyolefin causes yellowing and discoloration, polyolefin polymerized by Ziegler catalyst (containing chlorine compound residue)
It was found that yellowing and discoloration were also observed in polyolefins polymerized using a non-chlorine compound catalyst (for example, Phillips catalyst) containing a chlorine-containing additive.

As countermeasures against yellowing and discoloration, low-temperature molding and a method of adding a high-concentration pigment to suppress or mask the initial level of discoloration are conceivable, but these methods cannot be said to be highly effective. .

Accordingly, an object of the present invention is to provide a polyolefin composition which has sufficient antibacterial properties, does not discolor due to the addition of an antibacterial agent, and has excellent antibacterial properties having excellent hue stability and weather discoloration resistance. That is.

[0010]

Means for Solving the Problems As a result of intense research in view of the above problems, the present inventors have found that a polyolefin resin, along with specific <br/> antimicrobials, and silicone oil, and aluminum borate compounds, certain By adding a neutralizer and a phenolic compound and / or a hindered amine compound in combination, it was found that discoloration resistance, hue stability and weather discoloration resistance can be significantly improved without impairing antibacterial properties. The present invention has been made.

That is, the antimicrobial polyolefin composition of the present invention comprises (a)
One or two selected from the group consisting of silver, copper, zinc and tin
Antibacterial agent that holds more than one kind of metal in porous zeolite0 .
01-1.5 parts by weight, (b) 0.01-0.2 parts by weight of silicone oil, (c) 0.01-0.1 parts by weight of aluminum borate compound, (d) hydrotalcites, aluminum silicate
Calcium, oxides and hydroxides of Group II metals
At least one neutralizing agent selected from the group consisting of
And (e) a phenolic compound and / or a hindered amine compound in an amount of 0.01 to 0.5 part by weight.

Hereinafter, the present invention will be described in detail. The polyolefin resin that changes color by the addition of an antibacterial agent mainly contains a chlorine compound. Examples of the chlorine compound include a chlorine compound residue (TiC) of a Ziegler-Natta catalyst.
l _4, TiCl ₃₎ and, chlorinated paraffin, chlorinated polyethylene, or chlorine-containing additives such as flame retardants, such as perchlorethylene penta tricyclodecane, there are chlorine-containing polymers such other polyvinyl chloride.

The polyolefin itself may be a homopolymer of an α-olefin such as ethylene, propylene, butene-1, hexene-1, or 4-methylpentene-1, or a copolymer of ethylene with propylene or another α-olefin. Or a copolymer of two or more of these α-olefins. Among these, polyethylene such as polypropylene and low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, and high-density polyethylene are preferable. The polypropylene is not limited to a homopolymer, and a random or block copolymer with another α-olefin containing a propylene component of 50 mol% or more, preferably 80 mol% or more can be used. Comonomers copolymerized with propylene include ethylene and other α-olefins, with ethylene being particularly preferred. Thus, the term "polypropylene" as used herein is to be understood as not being limited to homopolymers of propylene but also including copolymers.

In the present invention, a thermoplastic olefin-based elastomer can also be used as the polyolefin resin.

The above thermoplastic olefin-based elastomer includes ethylene, propylene, 1-butene, 1-hexene, 4-
It means a copolymer rubber of two or more kinds of α-olefin such as methyl-pentene, or a copolymer of α-olefin and another kind of monomer. The copolymer rubber of two or more kinds of the α-olefins typically includes an ethylene-propylene copolymer rubber (EPR) and an ethylene-propylene-diene copolymer rubber (EPDM). As the diene in the ethylene-propylene-diene copolymer rubber (EPDM), a non-conjugated diene such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene or methylene norbornene or a conjugated diene such as butadiene or isoprene is used. be able to. Further, as the other monomer copolymerized with the α-olefin, vinyl acetate, acrylic acid ester and the like can be used. A typical example of a copolymer of an α-olefin and another monomer is an ethylene-vinyl acetate copolymer (EVA).

These polyolefins can be used by appropriately mixing them.

The antimicrobial polyolefin composition of the present invention comprises:
An antibacterial agent and a discoloration preventing additive are contained in the following mixing ratio with respect to 100 parts by weight of the polyolefin resin. (a) 0.01 to 1.5 parts by weight of antimicrobial agent (b) 0.01 to 0.2 parts by weight of silicone oil (c) 0.01 to 0.1 parts by weight of aluminum borate (d) 0.01 to 0.3 parts by weight of neutralizing agent (e) 0.01 -0.5 parts by weight of a phenolic compound and / or a hindered amine compound.

In the present invention, it is preferable to use (a) an inorganic antibacterial agent such as zeolite containing a metal having a bactericidal action from the viewpoint of antibacterial properties when blended with a polyolefin resin. In particular, a porous zeolite in which one or more metals selected from the group consisting of silver, copper, zinc and tin are held in an ionic state is preferable.

Examples of such an antibacterial agent include zeolite holding a metal having an antibacterial action proposed in Japanese Patent Publication No. 63-28402.

[0020] In the general formula _{xM 2 / n O · Al 2} O 3 · ySiO 2 · zH 2 O ( wherein as said zeolite, M represents a normal monovalent to trivalent metallic element, preferably Ag, Cu, Zn Etc., n is the valence of the metal, x and y are the coefficients of the metal oxide and silica with respect to Al ₂ O ₃ (assuming it is 1), and z is the coefficient of the water of crystallization. ) Are preferred.

Zeolite is preferably a porous zeolite having a cation exchange capacity of 1 meq / g (anhydrous basis) or more, a high ion exchange rate, and a large specific surface area, because of its suitability as a host for holding an antibacterial agent. As such a zeolite, for example, A-type, X-type or Y-type zeolite, synthetic zeolite such as synthetic mordenite, natural zeolite such as mordenite, clonobutyrolite, chabazite and the like are suitable.

Since the zeolite is contained in the polyolefin resin, a powdery product having a particle size as small as possible is preferable, and an active zeolite powder having an average particle size of 15 μm or less is particularly suitable for uniform dispersion. It is preferable that the above-mentioned powder has as little secondary aggregation as possible.

By using a zeolite having such properties, the amount of the above-mentioned antibacterial metal ion (s) alone or plurally adjusted is optionally adjusted by an ion exchange method to prepare an antibacterial agent having a desired antibacterial property. be able to.

The amount of the bactericidal metal is 0.005% by weight to the saturation amount based on the whole antibacterial agent. Here, the saturation amount is the saturation value of the ion exchange capacity of the zeolite used. If the metal content is less than 0.005% by weight, sufficient antibacterial action cannot be obtained. Preferred metal loading is 0.10-5.0
% By weight.

The antibacterial agent used in the present invention is prepared by adding a metal having a bactericidal effect to a porous zeolite having a cation exchange capacity of 1 meq / g (anhydrous basis) or more in an ion state of 0.005% by weight or more. To make the water content 5% by weight or less. If the amount of water is larger than this, discoloration is caused, which is not preferable. The heat activation is usually performed at 250 to 500 ° C (in an air atmosphere), but can be performed at 150 to 350 ° C under reduced pressure. Further, the zeolite mixed with a metal and heat-activated is appropriately pulverized to have an average particle size of 15 μm or less.

The content of the above antibacterial agent is polyolefin 10
0.01 to 1.5 parts by weight, preferably 0.1 to 1.5 parts by weight per 0 parts by weight
1.0 parts by weight. When the content of the antibacterial agent is less than 0.01 part by weight, the antibacterial property is not sufficient, and when it exceeds 1.5 parts by weight, the effect corresponding thereto cannot be improved and the degree of discoloration increases.

In the present invention, the silicone oil (b) is generally used as an agent for improving the lubricity of a resin or the like, and is mainly composed of a polymer mainly composed of dimethylpolysiloxane.

The above-mentioned silicone oil preferably has a viscosity of about 0.65 to 100,000 cs, and a specific gravity of about 0,000.
It is preferably about 87 to 1.3.

The content of the silicone oil is 0.01 to 0.2 parts by weight, preferably 0.02 to 0.1 parts by weight, based on 100 parts by weight of the polyolefin. When the content of the silicone oil is less than 0.01 part by weight, the effect of improving thermoformability and reducing discoloration is not sufficient, and when it exceeds 0.2 part by weight, the surface of the molded product bleeds and stickiness occurs.

In the present invention, (c) aluminum borate
Is a compound of the following general formula nAl_TwoO_Three・ MB_TwoO_Three  (Where n and m are integers of 1 to 9).
And specifically, 9Al_TwoO_Three・ 2B_TwoO_Three, 2Al
_TwoO_Three・ B_TwoO_ThreeAnd Al_TwoO_Three・ B_TwoO_ThreeIs mentioned
You. Of these, 9Al_TwoO_Three・ 2B_TwoO_ThreeIs good
Good.

[0031] The _{9Al 2 O 3 · 2B 2 O} 3 is boron by aluminum and oxygen in the network formed has a fully integrated structure, the composite oxide ones of aluminum and boron is there. For this reason, it has a higher covalent bond than ordinary salts, has high strength and high elasticity, and is excellent in heat resistance, chemical resistance and the like.

Such an aluminum borate compound is
Since it is added to the polyolefin resin, it is preferable to use a whisker or a fine powder. The above aluminum borate compound is preferably about 1 to 50 μm. The whisker and powder of the aluminum borate compound are preferably treated with an aminosilane-based coupling agent or an epoxysilane-based coupling agent as necessary.

The content of the aluminum borate compound is 0.01 to 0.1 part by weight, preferably 0.02 to 0.08 part by weight, based on 100 parts by weight of the polyolefin. If the content of the aluminum borate compound is less than 0.01 part by weight, the effect of reducing discoloration is not sufficient, and if it exceeds 0.1 part by weight, the whiteness decreases and the hue balance deteriorates.

(D) Examples of the neutralizing agent include hydrotalcites, aluminum calcium silicate, and periodic table II
Oxides and hydroxides of Group III metals can be used. The hydrotalcites do not include hydrated basic carbonates such as magnesium, calcium, zinc, aluminum and bismuth or water of crystallization thereof, and include natural products and synthetic products. As a natural product, Mg ₆ Al ₂
(OH) ₁₆ CO ₃ .4H ₂ O. Also,
As a synthetic product, Mg _0.7 Al _0.3 (OH) ₂ (CO ₃ ) _0.15
54H ₂ O, Mg _4.5 Al ₂ (OH) ₁₃ CO ₃・ 3.5H ₂ O, Mg _4.2 Al
₂ (OH) _12.4 CO ₃ , Zn ₆ Al ₂ (OH) ₁₆ CO ₃・ 4H ₂ O, Ca ₆ Al
₂ (OH) ₁₆ CO ₃ .4H ₂ O, Mg ₁₄ Bi ₂ (OH) _29.6 .4.2 H ₂ O and the like. Further, as the metal of Group II of the periodic table, magnesium, calcium, zinc and the like are preferable.

The content of the neutralizer is 10
0.01 to 0.3 parts by weight, preferably 0.01 to 0 parts by weight
It is 5 to 0.1 part by weight. When the content of the neutralizing agent is less than 0.01 part by weight, the effect of reducing discoloration is not sufficient, and when it exceeds 0.3 part by weight, the hue balance is deteriorated.

In the present invention, (e) the phenolic compound includes 2,6-di-t-butyl-p-cresol,
Diphenyl-4-octadecyloxyphenol, stearyl (3,5-di-t-butyl-4-hydroxyphenyl) propionate, distearyl (3,5-di-t-butyl-4-hydroxybenzyl) phosphonate, 2, 2'-methylenebis (4-
Methyl-6-t-butylphenol), 2,2'-methylenebis
(4-ethyl-6-t-butylphenol), bis [3,3-bis
(4-Hydroxy-3-t-butylphenyl) butyric acid] glycol ester, 4,4′-butylidenebis (6-t
-Butyl-m-cresol), 2,2′-ethylidenebis (4,6
-Di-t-butylphenol), 2,2'-ethylidenebis (4
-sec-butyl-6-t-butylphenol), 1,1,3-tris
(2-Methyl-4-hydroxy-5-t-butylphenyl) butane, bis [2-t-butyl-4-methyl-6- (2-hydroxy-3-t
-Butyl-5-methylbenzyl) phenyl] terephthalate, 1,3,5-tris (2,6-dimethyl-3-hydroxy-4-t-
Butylbenzyl) isocyanurate, 1,3,5-tris (3,5
-Di-t-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (3,5-di-t-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 1, 3,5-tris [(3,5-di-t-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, tris (3,5-
Di-tert-butyl-hydroxyphenyl) isocyanurate, pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, 2-tert-butyl-4-methyl- 6- (2'-acryloyloxy
-3'-t-butyl-5'-methylbenzyl) phenol, 3,9-bis (1 ', 1'-dimethyl-2'-hydroxyethyl) -2,4-8,10-
Tetraoxaspiro [5,5] undecanebis [β- (3-t
-Butyl-4-hydroxy-5-methylphenyl) propionate and the like. Of these, Tris (3,5
-Di-t-butyl-hydroxyphenyl) isocyanurate, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, 3,9-bis (1 ', 1'-dimethyl-2'-hydroxyethyl)-
Preferred is 2,4-8,10-tetraoxaspiro [5,5] undecanebis [β- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate.

As the hindered amine compound,
For example, di- (2,2,6,6-tetramethyl-4-piperidyl sebacate), 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1,2,3,4-tetra (2 , 2,6,6-tetramethyl-4-
Piperidyl) -butanetetracarboxylate, 1,4-di-
(2,2,6,6-tetramethyl-4-piperidyl) -2,3-butanedione, tris- (2,2,6,6-tetramethyl-4-piperidyl)
Trimellitate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, 1,2,2,6,6-pentamethyl-4-piperidyl-n-octoate, bis- (1,2,2,6 , 6-Pentamethyl-4-piperidyl) sebacate, tris- (2,2,6,6-tetramethyl-4-piperidyl) -nitrile acetate, 4-hydroxy-2,2,6,6-tetramethylpiperidine, 4 -Hydroxy-1,2,2,6,6-pentamethylpiperidine, polymethylpropyl-3-oxy [4- (2,2,6,6-tetramethyl) piperidyl] siloxane, dimethyl-1- (succinate) 2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate.

Of these, polymethylpropyl-3
-Hindered amine polysiloxane compounds such as -oxy [4- (2,2,6,6-tetramethyl) piperidyl] siloxane and dimethyl-1- (2-hydroxyethyl) -4-hydroxy-2,2,6, succinate , 6-Tetramethylpiperidine polycondensate and the like are preferred.

The phenolic compound and the hindered amine compound may be used alone or in combination.

The content of the phenolic compound and / or the hindered amine compound is 0.01 to 0.5 part by weight, preferably 0.01 to 0.5 part by weight, per 100 parts by weight of the polyolefin.
20 parts by weight. When the content of the phenolic compound and / or the hindered amine compound is less than 0.01 part by weight, the effects of suppressing discoloration, improving heat resistance, heat stability, and stability upon irradiation with ultraviolet light are not sufficient, and 0.5% by weight. Even if it exceeds the number of parts, the effect corresponding thereto cannot be improved.

The antibacterial polymer composition of the present invention is obtained by adding the above-mentioned additives to a polyolefin resin. In addition, other additives such as talc, mica, wollastonite are used for the purpose of modifying the polyolefin resin. And other inorganic fillers, heat stabilizers, light stabilizers, flame retardants, plasticizers, antistatic agents, release agents, foaming agents, nucleating agents, and the like.

The antimicrobial agent, silicone oil, aluminum borate compound, neutralizing agent,
In order to add the phenolic compound and / or the hindered amine compound and other additives to be added as necessary to the polyolefin resin, a generally used method may be used. For example, a method in which an antibacterial agent and these additives are blended with polyolefin, premixed, and kneaded with an extruder is suitable.

[0043]

The antimicrobial polyolefin composition of the present invention comprises a polyolefin resin containing a specific antimicrobial agent, silicone oil, an aluminum borate compound, a specific neutralizing agent, a phenolic compound and / or a hindered amine compound. Due to the compound addition, discoloration such as yellowing due to the blending of the antibacterial agent is extremely small, and the hue stability in high-temperature molding is improved, and the weathering discoloration resistance and the discoloration resistance during molding are also improved. Therefore, it has high commercial value in a wide range of applications.

Although it is not clear why such an effect is obtained, the silicone oil and the aluminum borate compound exhibit the effect of suppressing discoloration due to the antibacterial agent, and at the same time, the neutralizing agent, the phenolic compound and /
It is also considered that a hindered amine compound or the like exhibits stability during processing and an effect as a weather resistance stabilizer, and is particularly due to a synergistic effect due to the combined addition of these.

[0045]

The following examples show the hue stability, weathering discoloration resistance, molding processing stability, heat stability and antibacterial properties of the antimicrobial polyolefin composition in high-temperature molding. In addition,
The following were used as a raw material resin and various additives. [1] Polyolefin homopolypropylene: HPP [Melt flow rate (MF
R, 230 ° C, 2.16 kg load) 5 g / 10 min] [2] Antibacterial agent An: [ Zeolite antibacterial agent containing Ag and Zn ions, Bactekiller, manufactured by Kanebo Kasei Co., Ltd.] [3] Silicone oil 1: Dimethyl silicone oil [K45, manufactured by Nippon Unicar Co., Ltd., viscosity 1000cs] ・ SO-2: Fluorine-modified silicone oil [FS1265, manufactured by Toray Dow Silicone Co., Ltd., viscosity 1000cs] [4] Aluminum borate ・ G -1: aluminum borate whisker [9Al ₂ O ₃ .2B ₂ O
_3, Shikoku Chemicals Corp.] · G-2: that the aluminum borate whisker [the G-1 was treated with aminosilane coupling agent, manufactured by Shikoku Chemicals Corporation] · G-3: boric acid Aluminum whisker [The above G-1 is treated with an epoxysilane coupling agent, manufactured by Shikoku Chemicals Co., Ltd.] G-4: Aluminum borate whisker [The above G-1 is an aminosilane coupling agent and epoxysilane G - 5: Aluminum borate powder [Arbolite, manufactured by Shikoku Chemicals Co., Ltd.] [5] Neutralizing agent • D-1 : Basic magnesium aluminum hydroxy carbonate hydrate [Mg _4.5 Al ₂ (OH) ₁₃
・ CO ₃・ 3.5H ₂ O, DHT-4A, manufactured by Kyowa Chemical Industry Co., Ltd. ・ ・ Ca-St: calcium stearate [Nitto Kasei Co., Ltd.]
・ MgO: Magnesium oxide [Micromag (manufactured by Kyowa Chemical Industry Co., Ltd.)] ・ ZnO: Zinc oxide [5] phenolic compound ・ Ph-1: Pentaerythrityl-tetrakis [3- (3,5-di)
-t-butyl-4-hydroxyphenyl) propionate]
Methane [Irganox1010, Ciba-Geigy] Ph-2: 3,9-bis [1,1-dimethyl-2- {β- (3-t-butyl-4hydroxy-5methylphenyl) propionyl} ethyl] -2 , 4,8,10-Tetraoxpicaro [5,5] undecane [Sumilyzer GA80, manufactured by Sumitomo Chemical Co., Ltd.] [6] Hindered amine compounds ・ HALS-1: dimethyl-1- (2-hydroxysuccinate) ethyl)-
4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate [TINUVIN 622LD, manufactured by Ciba Geigy ] HALS-2: polymethylpropyl-3-oxy [1 (2,2,6,6-
Tetramethyl) piperidyl] siloxane [UVASIL 299
(Manufactured by Enichem Synthesis) [7] Phosphorus compound ・ P-1: tris (2,4-di-t-butylphenyl) phosphite [Mark2112, manufactured by Adeka Argus Co.] ・ P-2: di (2, 4-di-t-butylphenyl) pentaerythritol diphosphite (Ultranox 626, GE
[8] Sulfur compounds ・ S-1: distearyl thiodipropionate [DSTDP,
Sumitomo Chemical Co., Ltd.)

Examples 1 to 14 In 100 parts by weight of homopolypropylene (HPP), an antibacterial agent, silicone oil (SO-1 or SO-2), and aluminum borate compounds (G-1, G −
2, G-3, G-4 or G-5), neutralizing agents (D-1, C
a-St, MgO or ZnO), a phenolic compound (Ph-1 or Ph-2 ), and a hindered amine compound (HALS-1 or HALS-2), respectively, and premixed with a Henschel mixer. This mixture is extruded (30 mmφ, L / D = 26) using
rpm, and melt-kneaded by _{N 2} blow under and pelletized. The resin temperature in the extruder was 180 ° C. at the rear of the cylinder (hopper side), 210 ° C. at the center of the cylinder, 230 ° C. at the front of the cylinder, and 230 ° C. at the die. The initial hue (b-value of Hunter) after molding of the obtained pellets was measured by reflection measurement using an SM-4-2 type color computer (integrating sphere type two optical path system) manufactured by Suga Test Instruments Co., Ltd.

Next, the pellets were transferred to Shoji Iron Works Co., Ltd.
Pressing temperature 230 ° C, preheating time 3 minutes, degassing time 1.5 seconds (6 times), pressurizing time 1 minute 170 kg / cm ² P. G. FIG. After pressurizing, it is quickly transferred to a cooling press (20 ° C.) and pressurized for 170 minutes in 1 minute.
/ Cm ² P. G. FIG. To form a test piece (test piece) having a thickness of 2 mm. The hue of the test piece thus obtained was measured for reflection.

Further, a black panel temperature of 83 ° C. ± 5 ° C. was applied to the test piece using an ultraviolet long life fade meter (FAL-5H type, manufactured by Suga Test Instruments Co., Ltd.).
Ultraviolet rays were irradiated for 82 hours, and the hue after the irradiation was measured for reflection.

Further, the pellets can be obtained by using Shoji Iron Works Co., Ltd.
Press molding temperature 230 ° C, preheating time 15 minutes, degassing time 1.5 seconds (6 times), pressurizing time 1
100 kg / cm ² P. G. FIG. After pressurizing, quickly move to a cooling press (20 ° C) and pressurize for 100 minutes in 1 minute
g / ^cm 2 P. G. FIG. To form a test piece (test piece) having a thickness of 2 mm. The hue of the test piece thus obtained was measured for reflection.

Table 2 shows the measurement results of these hues.
Furthermore, the evaluation of the antibacterial property of this test piece was evaluated. The results are shown in Table 2.

Comparative Examples 1 to 7 The same hue measurement and antibacterial evaluation were carried out for compositions in which at least one of silicone oil, aluminum borate compound, neutralizer, phenolic compound and hindered amine compound was omitted. I went . In addition, additives
Their respective blended, subjected to preliminary mixing in a Henschel mixer, then the mixture extruder (30mmφ, L / D =
In 26), 50 rpm, and melt-kneaded by _{N 2} blow under and pelletized. In addition, a phosphorus compound (P-1 or P
-2) and the sulfur compound (S-1) are usually used as antioxidants.

The composition of the obtained antibacterial polypropylene composition is shown first. Using this composition, Example 1
The hue was measured and the antibacterial property was evaluated in the same manner as described above. The result is second displayed.

[0053]

Table 1 (continued) Composition (parts by weight) Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Polyolefin HPP 100 100 100 100 100 100 Antibacterial agent (An) 1.0 0.5 0.5 0.5 0.5 0.5 Silicone oil SO-1 0.05 0.05 0.05 0.05 0.05 0.05 Aluminum borate G-4 0.05 0.05 0.05 0.05 0.05 0.05 Neutralizer D-1 0.05 0.05 0.05---Ca-St-----0.05 MgO-- -0.05--ZnO----0.05-Phenol compound Ph-1 0.05-0.05 0.05 0.05 0.05 Hindered amine compound HALS-1-0.10 0.05---

[0055]

Table 1 (continued) Composition (parts by weight) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Polyolefin HPP 100 100 100 100 Antibacterial agent (An) 0.5 0.5 0.5 0.5 Neutralizer D-1 0.05 0.05 0.05 0.05 Phenol compound Ph-1 0.05 0.05 0.05-Ph-2---0.05 Hindered amine compound HALS-1--0.05-Phosphorus compound P-1 0.05---Sulfur compound S-1-0.05--

[0057]

Table 2 Physical properties Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Hue stability ⁽¹⁾ Initial value ◎ ◎ ○ ◎ ◎ ◎ Test piece ◎ ◎ ○ ◎ ◎ ◎ Test piece ○ ○ ○ ◎ ○ ○ After UV irradiation ◎ ◎ ○ ◎ ○ ◎ Antibacterial ⁽²⁾ ◎ ◎ ◎ ◎ ◎ ◎ ◎

Table 2 (continued) Physical properties Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Hue stability ⁽¹⁾ Initial value ◎ ◎ ◎ ◎ ◎ ◎ Test piece ○ ○ ○ ◎ ◎ ○ Test piece ○ ○ ○ ○ ○ ○ After UV irradiation ○ ○ ○ ◎ ◎ ○ Antibacterial ⁽²⁾ ◎ ◎ ◎ ◎ ◎ ◎ ◎

Table 2 (continued) Physical properties Example 13 Example 14 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Hue stability ⁽¹⁾ Initial value ◎ ◎ ◎ ◎ ◎ ○ Test piece ◎ ◎ △ × ○ × Test piece ◎ ○ × ×× × ×× After UV irradiation ◎ ◎ ×× × × × Antibacterial ⁽²⁾ ◎ ◎ ◎ ◎ ◎ ◎

[0061]

(1) Hue stability: Evaluated according to the following criteria based on the measured value of the b value of the Hunter. Initial value ◎: b value is less than 0.5. ：: The b value is 0.5 to less than 1.5. Δ: b value is less than 1.5 to less than 2.5. X: b value is 2.5 to less than 3.0. Xx: b value is 3.0 or more. 片 : b value is less than -4.0 after test piece and after UV irradiation . ：: b value is -4. 0 to less than -2.5. Δ: b value is -2.5 to less than -0.5. X: b value is -0.5 to less than +0.5. Xx: b value is +0.5 or more. (2) Antibacterial activity: Escherichia coli solution was dropped on the test piece , and the number of bacteria after storage at 23 ° C. for 24 hours and 48 hours was determined with the theoretical number of bacteria added being 3.1 × 10 ⁶ . ◎: After 24 hours and 48 hours, both were below the limit value of the bacterial cell count.

As is clear from Table 2, the antibacterial polyolefin composition of the present invention has good antibacterial properties, the degree of discoloration after pellet molding and after injection molding is kept low, and furthermore, ultraviolet irradiation. The degree of subsequent discoloration was also small.

[0064]

The antimicrobial polyolefin composition of the present invention has sufficient antibacterial properties and resistance to discoloration during molding, and the yellowing and discoloration due to the compounding of the antibacterial agent are suppressed to a sufficiently satisfactory level. Moreover, the weathering resistance is also improved. The antibacterial polyolefin composition having such characteristics is suitable for various kitchen utensils, bath utensils, and other water-use products.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ identification code FI C08K 9:12) (C08L 23/00 83:04) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 23 / 00-23/36 C08K 3/00-13/08

Claims (1)

(57) [Claims] 1. A polyolefin resin based on 100 parts by weight of (a) one selected from the group consisting of silver, copper, zinc and tin.
0.01 to 1.5 parts by weight of an antibacterial agent having one or more metals retained on the porous zeolite, and (b) silicone oil 0.01
~ 0.2 parts by weight, and (c) aluminum borate compound 0.01 ~
0.1 parts by weight, (d) hydrotalcites, aluminum silicate
Minium calcium, oxides of metals of group II of the periodic table
And 0.01 to 0.3 parts by weight of at least one neutralizing agent selected from the group consisting of phenolic compounds and / or hindered amine compounds. Antimicrobial polyolefin composition.