JPH10120885A - Injection-molded product of antibacterial polyester resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a highly antistatic polyester injection molding by using a composition comprising a polyester resin and a specified silver-containing inorganic antibacterial agent. SOLUTION: This molding is obtained by injection-molding a resin composition comprising a polyester resin (A) and a water-soluble glass (B) containing antibacterial metal ions and/or antibacterial metal atoms and having a mean article diameter of 0.1-20μm. Alternatively, it is obtained by injection-molding a resin composition comprising a polyester resin (A), a resin (C) other than A and a water-soluble glass (B) containing antibacterial metal ions and/or an antibacterial metal and having a mean particle diameter of 0.1-20μm. Component A is a polymer or copolymer obtained by condensing an acid component based on an aromatic dicarboxylic acid or its esterifiable derivative with a diol component. Component B is exemplified by Ag2 O, CuO or ZnO.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition comprising a polyester resin or a thermoplastic resin containing a polyester resin mixed with a water-soluble glass containing an antibacterial metal ion and / or an antibacterial metal by injection molding. It relates to the obtained antibacterial injection molded product.

[0002]

2. Description of the Related Art An injection molded product obtained from a polyester resin or a thermoplastic resin containing a polyester resin has electrical characteristics, heat resistance, and the like.
It is excellent in flame retardancy and chemical resistance, and has been widely used for various heat appliances, electric / electronic machine parts, automotive parts, etc., and more recently for water parts such as washrooms and toilets. . In recent years, there has been a problem that bacteria are generated in these products and adversely affect the human body.

[0003] JP-A-4-352964, Japanese Patent Publication No.
In the field of fibers and films, for example, polyesters having antibacterial properties are reported in, for example, JP-A-19258, but in the field of injection molding, polyester resins having excellent antibacterial properties have not yet been found.

In the case of an injection molded product obtained from a resin other than a polyester resin, for example, a support type silver-based inorganic antibacterial agent is kneaded in a process of extruding polypropylene, polyethylene, polyamide, acrylonitrile-butadiene-styrene resin, etc. The one to which the property is imparted has been found.

[0005] However, no excellent antibacterial property was found even when a carrier type silver-based inorganic antibacterial agent was used in a polyester resin or a thermoplastic resin containing the polyester resin.

An object of the present invention is to impart antibacterial properties to an injection molded article made of a polyester resin or a thermoplastic resin containing the polyester resin.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, a specific silver-based inorganic antibacterial agent, more specifically, an antibacterial metal ion and / or an antibacterial metal is contained as an antibacterial agent. The inventors have found that a polyester resin injection molded article having excellent antibacterial properties can be obtained by using a water-soluble glass, and have reached the present invention.

That is, the gist of the present invention is as follows.
A resin composition comprising a polyester resin (A) or a thermoplastic resin containing a polyester resin and a water-soluble glass (B) containing an antibacterial metal ion and / or an antibacterial metal and having an average particle size of 0.1 to 20 μm. Antimicrobial injection molded products obtained by injection molding.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester resin used as the component (A) in the present invention is obtained by a condensation reaction between an acid component mainly containing an aromatic dicarboxylic acid or an ester-forming derivative thereof and a diol component. It is a polymer or a copolymer.

The aromatic dicarboxylic acid or its ester-forming derivative used as the acid component includes terephthalic acid, isophthalic acid, phthalic acid, naphthalene 1,4- or 2,6-dicarboxylic acid, bis (p-carboxyphenyl) Examples thereof include methane, anthracene dicarboxylic acid, 4,4′-diphenyl dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, and the like, and ester-forming derivatives thereof such as dialkyl esters and diallyl esters. In addition, as the acid component, an aliphatic dicarboxylic acid such as glutaric acid, adipic acid, sebacic acid, oxalic acid, and succinic acid, or an ester-forming derivative thereof can also be used.

As the diol component, ethylene glycol, propylene glycol, 1,4-butanediol,
Neopentyl glycol, 1,5-pentanediol,
1,6-hexanediol, decamethylene glycol,
Examples thereof include cyclohexanediol, 2,2-bis (4-hydroxyphenyl) propane, polyethylene glycol, poly-1,3-propylene glycol, and polytetramethylene glycol.

The polyester resin (A) preferably used in the present invention includes polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, polyhexamethylene terephthalate,
Examples thereof include polycyclohexane dimethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate, and these can be used alone or as a mixture of two or more. Above all, polyethylene terephthalate (PET), polybutylene terephthalate (PBT)
Alternatively, a copolymer mainly composed of these is preferable.

The polyester resin (A) is preferably contained in the resin composition in the range of 10 to 100% by weight, more preferably 30 to 100% by weight. If the polyester alloy is less than 30% by weight, the original heat resistance, mechanical properties, and the like of the polyester resin are difficult to obtain.

The polyester resin (A) has an intrinsic viscosity [η] of 0.6 to 1.2, preferably 0.65 to 0.9. If the intrinsic viscosity [η] is less than 0.6, the mechanical strength tends to decrease, and if it exceeds 1.2, the fluidity tends to decrease.

The water-soluble glass used for the component (B) of the present invention is one or more network-forming oxides of SiO ₂ , B ₂ O ₃ and P ₂ O ₅ , Na ₂ O, K ₂₀ CaO,
MgO, BaO, one or more network modifier oxides of ZnO and Al ₂ O _3, TiO ₂ in one or two
It is composed of a glass composition containing at least one kind of network intermediate oxide.

The antibacterial metal ion and / or antibacterial metal used for the component (B) is Ag ₂ O, CuO, Zn
It is derived from one or more antibacterial metal oxides such as O, PbO, NiO and CdO. Ag ₂ O is particularly preferred as the antibacterial metallic metal oxide, and silver ions and / or metallic silver exhibit the most antibacterial effect in practical use. Further, ZnO may be used in combination.

The component (B) contains 0.1 to 20.0% by weight of an antibacterial metal ion and / or an antibacterial metal.

The average particle size of these water-soluble glasses is 0.1.
It is 1 to 20 μm, particularly preferably 0.5 to 5 μm. If the average particle size is less than 0.5 μm, it is difficult to produce the water-soluble glass itself, and if the average particle size exceeds 20 μm, poor appearance is likely to occur due to a decrease in surface smoothness of the injection molded product.

The amount of the water-soluble glass is preferably in the range of 0.05 to 5.0 parts by weight, more preferably 0.5 to 2.0 parts by weight, based on 100 parts by weight of the resin composition. Range of parts. If the amount of the antibacterial agent is too small, the antibacterial property will not be exhibited depending on the resin composition. If the amount is too large, the cost of raw materials will increase, and the appearance of the molded article will be poor.

The resin other than the polyester resin used as the component (C) of the present invention may be a thermoplastic resin, but is mainly composed of acrylonitrile-butadiene-styrene resin, polycarbonate resin, polyethylene Resin, polypropylene resin, polyvinyl chloride resin, fluorine resin, polyamide resin, polyvinyl alcohol resin, silicone resin, acrylic resin, polyurethane resin and the like. Particularly, acrylonitrile-butadiene-styrene resin and polycarbonate resin are preferable.

The resin (B) other than the polyester resin is
It is preferably contained in the resin composition in a range of 0 to 90% by weight, more preferably 20 to 80% by weight.

The type and the mixing method of the fibrous reinforcing material (D) used in the present invention are not particularly limited. For example, glass fiber, inorganic fiber other than glass fiber, carbon fiber, Heat-resistant organic fibers can be used. Specifically, the fiber diameter is 1 to 20 μm, the fiber length is 1
Chopped strand of glass fiber or carbon fiber of 0 mm or less, glass fiber milled fiber, pitch-based carbon fiber, aromatic polyamide fiber, aromatic polyimide fiber,
Aromatic polyamide-imide fibers, combinations of these, and the like can be used. Among them, glass fiber chopped strands are particularly preferred.

The content of the fibrous reinforcing material (D) in the resin composition is preferably in the range of 1 to 80% by weight, and more preferably in the range of 15 to 50% by weight. When the amount of the fibrous reinforcement is less than 1% by weight, heat resistance, mechanical properties, and the like are difficult to obtain, and when the amount is more than 80% by weight, poor appearance is likely to occur due to the fibrous reinforcement rising to the surface of the molded product.

The flame retardant (E) used in the present invention includes phosphoric ester flame retardants such as non-halogen-containing flame represented by triphenyl phosphate and tricresyl phosphate and halogen-containing flame represented by tris phosphate. Chlorinated paraffins, chlorinated polyethylenes and halogen-containing flame retardants such as tetrabromobisphenol A represented by chlorinated polyethylene perchloropentacyclodecane, and bromine represented by decabromodiphenyl oxide; antimony trioxide; aluminum hydroxide; There are inorganic flame retardants represented by boron compounds. These flame retardants (E) are 1
Species can be used alone or in combination of two or more. Among them, the combined use of a brominated flame retardant and antimony trioxide is preferred.

The content of the flame retardant (E) in the resin composition varies depending on the resin composition, but is preferably in the range of 3 to 50% by weight, more preferably 5 to 20% by weight in the resin composition. % Is preferred.

The resin composition used in the present invention may contain other inorganic solids, for example, particulate or amorphous fillers such as calcium carbonate, titanium oxide, feldspar minerals, clay, white carbon, carbon black, glass beads, and the like. Plate-like fillers such as kaolin, clay and talc, and scale-like fillers such as glass flakes and mica graphite can also be added.

Further, additives such as a heat stabilizer, an antioxidant, a light stabilizer, a release agent, a surfactant, a water repellent, a curing agent, a plasticizer, a thickener, a pigment and an antistatic agent are added. May be.

The antibacterialization of a thermoplastic resin molded article is mainly known by a method of applying a coating or coating of an antibacterial agent on the surface of the molded article and a method of kneading and mixing the antibacterial agent in the resin in the extrusion step. However, when the latter method is used, poor dispersion of the antibacterial agent occurs depending on the resin composition or the kind of the antibacterial agent, resulting in a decrease in the antibacterial effect and a poor expression of the antibacterial performance. This phenomenon is often observed in the silver-carrying type among silver-based inorganic antibacterial agents. Due to poor dispersion, the antibacterial agent of an antibacterial amount is not distributed on the surface of the molded product, and the amount of contact with bacteria is reduced, and the antibacterial effect is reduced. Solutions include improving the dispersibility of the resin and the antimicrobial agent by forming a masterbatch and adding a dispersant. In the present invention, antibacterialization is also performed by the latter method, but the effect of antibacterial performance on the dispersibility of the antibacterial agent is not recognized. This is because the water-soluble glass used is the silver-eluting type among silver-based inorganic antibacterial agents, and the water-soluble glass contained in the resin is decomposed by moisture even if the antibacterial agent itself is not distributed on the surface of the molded product This is because antibacterial metal ions having an antibacterial action are eluted and released on the surface of the molded article. In the present invention, it is not particularly necessary to form a masterbatch of a resin and an antibacterial agent, and to add a dispersant, but such a method may be used as a production method.

The antibacterial property of the injection molded article of the antibacterial polyester resin of the present invention is strong against bacteria (bacterium) such as Escherichia coli and Staphylococcus aureus, and also excellent against fungi (mold). Shows mold resistance.

The antibacterial polyester resin injection molded product of the present invention can be used in a wide range of fields such as various heat appliances, electric / electronic machine parts, automobile parts, and water-running parts such as kitchens, washrooms and toilets. It is.

Hereinafter, the present invention will be described specifically with reference to examples. The antibacterial activity test in the experimental examples is a value measured as follows.

Antimicrobial activity test method 1) Test piece shape 40 mm x 40 mm molded product 2) Antimicrobial activity measurement method (film adhesion method) A test specimen is put into a sterile petri dish, a test bacterial solution is dropped, and a polyethylene film is covered thereon. This was stored at 37 ° C., and the viable cell count after 24 hours was measured. The number of target bacteria is the number of viable bacteria after storage at 37 ° C. for 24 hours without a test piece.

3) Test strain Escherichia coli IFO 3301
(Escherichia coli) Staphylococcus aureus IFO
12732 (Staphylococcus aureus) 4) Antibacterial evaluation criteria ：: Both Escherichia coli and Staphylococcus aureus are reduced to 99% or less of the number of bacteria at the start of the test. Δ: The number of bacteria after the test was reduced to 99% or less of the number of bacteria at the start only of E. coli. X: The number of bacteria after the test was not reduced to 99% or less of the number of bacteria at the start of both E. coli and Staphylococcus aureus.

(Examples 1 to 12, Comparative Examples 1 to 8) Various resins and the like were blended according to the compositions shown in Tables 1 and 2, and each was uniformly mixed in a V-type blender for 5 minutes. This mixture was mixed with a 40 mmφ extruder with L / D = 25 for 250 minutes.
Extruded at ℃ and pelletized. The obtained molding pellets were dried with hot air at 120 ° C. for 4 hours.
3.5 oz screw-in-line injection molding machine
Injection molding was performed at a cylinder temperature of 250 ° C., a mold temperature of 80 ° C., and a molding cycle of 35 seconds. Using the test pieces obtained therefrom, an antibacterial test by a film adhesion method and a measurement of tensile strength according to ASTM were performed. Tables 1 and 2 show the results of the antibacterial test and the tensile strength.

The various resins and the like used are as follows. PBT-1: N-1000 manufactured by Mitsubishi Rayon Co., Ltd. PBT-2: N-1100 manufactured by Mitsubishi Rayon Co., Ltd. PBT-3: N-1300 PET resin manufactured by Mitsubishi Rayon Co., Ltd. MA521H- manufactured by Mitsubishi Rayon Co., Ltd. D ABS resin: butadiene: acrylonitrile: styrene = 37% by weight: 18% by weight: 45% by weight Glass fiber-1: 13 μm in diameter, 3 mm chop Glass fiber-2: 10 μm in diameter, 3 mm chop Flame retardant-1: Sakamoto Chemical Co., Ltd. ) SR-BSP (brominated epoxy) Flame retardant-2: Sakamoto Chemical Co., Ltd. SR-T2000 (brominated epoxy) water-soluble glass Average particle size 10 μm: Nippon Sheet Glass P-10 water-soluble glass average Particle size 5 μm: manufactured by Nippon Sheet Glass Co., Ltd.
P-05

[0036]

[Table 1]

[0037]

[Table 2]

(Examples 13 to 15) The injection molded product obtained in Example 5 was subjected to a light fastness test at 83 ° C. for 400 hours (Example 14) and 1000 hours (Example 15) and an oven 80 hours. An antibacterial test after a heat resistance test at 400C for 400 hours (Example 13) was performed. Table 3 shows the results.

[0039]

[Table 3]

[0040]

The antibacterial polyester resin injection molded article of the present invention is obtained by mixing a polyester resin or a resin composition containing polyester with a water-soluble glass containing antibacterial metal ions and an antibacterial metal. Antibacterial properties can be imparted to polyester resin injection molded products without adding batches or dispersants, and the antibacterial properties do not deteriorate even after heat aging and light irradiation without impairing the original properties It is possible to obtain an injection molded product of a hydrophilic polyester resin.

Claims (5)

[Claims] 1. A resin composition comprising a polyester resin (A) and a water-soluble glass (B) containing an antibacterial metal ion and / or an antibacterial metal and having an average particle size of 0.1 to 20 μm is injection-molded. Antimicrobial polyester resin injection molded product obtained by 2. An average particle size of 0.1 to 20 μm containing a polyester resin (A), a resin (C) other than the polyester resin, and an antibacterial metal ion and / or an antibacterial metal.
m, an antibacterial polyester resin injection molded product obtained by injection molding a resin composition comprising the water-soluble glass (B). 3. An antibacterial polyester resin injection molded product obtained by injection molding a resin composition obtained by blending a fibrous reinforcing material (D) with the resin composition according to claim 1 or 2. 4. An antibacterial polyester resin injection molded product obtained by injection molding a resin composition in which a flame retardant (E) is blended with the resin composition according to claim 1 or 2. 5. An antibacterial polyester resin injection molded product obtained by injection molding a resin composition comprising the resin composition according to claim 3 and a flame retardant (E).