JP2005179607A - Antibacterial composite particle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antibacterial composite particle capable of exhibiting sufficient antibacterial properties when blended in a resin molded product, a fiber, or the like, and to provide a process for producing the antibacterial composite particle. <P>SOLUTION: This antibacterial composite particle comprises an antibacterial inorganic particle A having silver or a silver ion and a degree of hydrophobization of 20% or less and an antibacterial inorganic particle B having a degree of hydrophobization of 30% or more and a volume average particle size of 0.01-3 μm. The antibacterial inorganic particle B is an oxide containing zinc, titanium, copper or nickel. An addition amount ratio of the antibacterial inorganic particle A to the antibacterial inorganic particle B is 1:7-1:0.25. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to antibacterial composite particles to be blended for imparting an antibacterial function to resin products and the like.

  In general, antibacterial agents formulated to impart antibacterial functions to resin products such as fibers and plastic products are broadly divided into inorganic antibacterial agents and organic antibacterial agents, and inorganic antibacterial agents are more safe for the human body. It is used because it is high and has a relatively excellent antibacterial function. Silver, copper, zinc, titanium, etc. are commonly used as metals or metal ions that give antibacterial activity with such inorganic antibacterial agents, but silver is widely used.

  For example, Patent Document 1 discloses a polyamide composition containing zeolite particles supporting 5 to 15% by weight of silver ions, wherein the zeolite particles are high silica mordenite, and the number average particle diameter thereof is 0.1 μm. Thus, an antibacterial polyamide composition in which the proportion of particles having a particle diameter exceeding 1 μm is 20% by weight or less is disclosed.

  In addition, methods for imparting antibacterial properties to resin products can be broadly classified into kneading methods and post-processing methods. The kneading method is a method of adding an antibacterial agent at the manufacturing stage of plastic molded products, synthetic fibers, films, etc., and generally, after preparing the master pellet by kneading the antibacterial agent and resin with an extruder, A molded product is produced by an injection molding machine. The post-processing method is a method in which an antibacterial agent is fixed to the surface with a binder, a coating agent, or the like, and a method of painting on the final product with an antibacterial agent paint is common. Of these two methods, the kneading method is preferably used in consideration of production cost and long-term durability.

  However, even with such a kneading method, various problems must be solved in order to stably develop the antibacterial effect.

  In order for an antibacterial product to exhibit an antibacterial effect, the antibacterial agent must be appropriately exposed on the outermost surface of the product and come into contact with bacteria. If the antibacterial agent gets inside the product or falls off the surface, the antibacterial effect does not appear. In the kneading method, an antibacterial agent having a large particle size is undesirably removed from the product surface during production or repeated use, and may cause wear on the contact portion of the production apparatus. In addition, an antibacterial agent having a large particle size is undesirable because it may cause deterioration of the strength of the molded product, fiber strength, and feel and texture. Furthermore, when an antibacterial agent having a large particle size is produced by injection molding, there is a problem in that the antibacterial agent cannot be uniformly dispersed because the antibacterial agent cannot be uniformly dispersed in a molded body having a complicated shape. It was.

  For example, Patent Document 2 discloses a functional particle having a particle size of 0.01 to 200 μm, which includes a calcium phosphate compound, titanium dioxide, activated carbon, zeolite, molecular sieve, an inorganic deodorant, an inorganic antibacterial agent, or a mixture thereof. There is a description of a method for producing a non-woven fabric treated with 1.

  However, the method described in Patent Document 2 is a production method in which an antibacterial agent is dispersed in water and applied to a non-woven fabric. In order to prevent aggregation in water and stabilize particles, an antibacterial agent having a large particle size is used. The use of agents is desired. On the other hand, in the method of kneading into a resin, the antibacterial agent on the large particle size side in the range described in Patent Document 2 is detached from the surface due to physical stress and surface rubbing during production and use. As a result, sufficient antibacterial properties could not be expressed.

  Silver and silver ions have a high reduction potential and strong antibacterial activity, but when kneaded into a resin or the like, antibacterial activity is difficult to be stably exhibited due to the influence of a small amount of coexisting impurity ions or metals used as various additives. In some cases, discoloration of the blended substrate occurred. Specifically, the presence of chlorine, sulfur, and nitrogen-based antioxidants, reducing agents, fragrances, and stabilizers may inhibit antibacterial activity, and may be affected by chlorine-based gases, sulfur-based gases, and nitrogen-based gases. Sometimes yellowing occurred. Such yellowing and antibacterial inhibition are known in addition to the above-mentioned antagonists, and are particularly susceptible to the influence of heat, light and moisture. These are considered to promote the dissociation of silver ions and affect the deterioration of the resin and the chemical reaction rate.

  The method described in Patent Document 2 has a problem in terms of antagonist resistance. In particular, when a chemical treatment containing chlorine, bromine, sulfur, and nitrogen atoms is performed, the problem that antibacterial properties are vitally active. there were.

  Therefore, antibacterial agents having antagonist resistance and discoloration resistance against light and heat have been proposed. For example, Patent Document 3 discloses a phosphate antibacterial agent in which at least one metal compound selected from Ti, Zr or Zn is coated on the surface of a sparingly soluble phosphate carrying at least silver ions as antibacterial ions. Is disclosed.

  Patent Document 4 describes that a silver antibacterial agent and a zinc antibacterial agent are used in combination.

JP-A-8-151515 JP-A-6-192961 JP-A-6-172113 International Publication No. 03/033596 Pamphlet

  However, in Patent Document 3, since the silver antibacterial agent is coated with one or more metal compounds selected from Ti, Zr, or Zn and has a high degree of hydrophobicity, the antibacterial activity against hydrophilic bacteria is currently The antibacterial requirement was not enough.

  Moreover, in the said patent document 4, since the zinc type antibacterial agent is not hydrophobized, the zinc type antibacterial agent has low wettability with respect to the base material and generally has a small particle diameter. Depending on the situation, it may fall off from the surface and may not exhibit sufficient antibacterial properties.

  In recent years, an antibacterial agent composition that exhibits a stable antibacterial effect against the material composition of synthetic resin, synthetic fiber, nonwoven fabric, synthetic paper, etc., coexisting impurities, ions, mechanical stress during production and use is required. It was done.

  There has also been a demand for an antibacterial agent composition that does not cause discoloration or deterioration in physical properties of synthetic resin, synthetic fiber, nonwoven fabric, synthetic paper, and the like to be blended.

  Furthermore, there has been a demand for a composition that exhibits a stable antibacterial property independent of the shape of a molded body using a synthetic resin.

  This invention is made | formed in view of the said situation, and it aims at providing the antimicrobial composite particle which can express sufficient antimicrobial property in a resin molding, a fiber, etc., and its manufacturing method.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have identified that the antibacterial agent specified in the antibacterial composite particles to be blended with the resin molded body or fiber is two types of antibacterial agents having specific particle sizes. The present inventors have found that the above problems can be solved by combining the above, and have completed the present invention.

  (1) Antibacterial inorganic particles A having silver or silver ions and having a degree of hydrophobicity of 20% or less, a degree of hydrophobicity of 30% or more, and a volume average particle size of 0.01 to 3 μm And antibacterial inorganic particles B, which are antibacterial composite particles.

  (2) The antibacterial inorganic particles A have a volume average particle size of 0.02 to 5 μm, and the antibacterial inorganic particles B have a volume average particle size of 0.01 to 3 μm. It is an antibacterial composite particle as described in 1).

  (3) The antibacterial composite particle according to (1), wherein the antibacterial inorganic particle B is an oxide containing zinc, titanium, copper, or nickel.

  (4) The antibacterial composite particle according to (1), wherein the addition ratio of the antibacterial inorganic particle A and the antibacterial inorganic particle B is 1: 7 to 1: 0.25. is there.

  (5) The antibacterial composite particles according to (1) above, wherein the antibacterial inorganic particles A are those in which silver or silver ions are supported on a phosphate compound.

  (6) The antibacterial composite particles according to (1) above, wherein the total amount of the antibacterial inorganic particles A and the antibacterial inorganic particles B is 0.1 wt% or more and 60 wt% or less It is.

  (7) The antibacterial inorganic particles A and the antibacterial inorganic particles B are surface-treated with a surface treatment agent containing at least one of Si, Al, and Ti. Composite particles.

  (8) The antibacterial composite particle according to any one of (1) to (7), wherein the antibacterial composite particle contains a resin, and the resin is a thermoplastic resin.

  (9) The antibacterial composite particles are characterized in that at least the antibacterial inorganic particles A, the antibacterial inorganic particles B, and the resin are melt-kneaded and cooled, and then pulverized so that the volume average particle diameter is 1 to 2000 μm. The antibacterial composite particles according to any one of (1) to (7) above.

  (10) An antibacterial fiber in which the antibacterial composite particles according to any one of (1) to (9) are blended.

  (11) An antibacterial resin molded product in which the antibacterial composite particles according to any one of (1) to (9) are blended.

  According to the present invention, the antibacterial composite particles using a plurality of antibacterial agents having different particle diameters can maintain and exhibit an antibacterial effect without falling off from the surface of the molded body even during production and repeated use. it can.

  Furthermore, the antibacterial composite particles of the present invention alleviate the antibacterial inhibitory action of the silver-based antibacterial agent by the compound having chlorine, sulfur, nitrogen, etc., and combine the antibacterial inorganic particles A and B to form a resin molded body or The fiber can exhibit sufficient antibacterial properties and can maintain the antibacterial properties.

  In order to mix antibacterial ceramics with the raw material polymer of various synthetic resin molded products, first, a masterbatch containing the antibacterial agent at a high concentration is manufactured as the first step, and then the raw material polymer of the molded product as the second step. In general, a master batch is added and mixed together so that the antibacterial agent has a predetermined concentration. When performing such a manufacturing method, it is necessary to melt | dissolve the raw material polymer of a masterbatch and a molded article simultaneously. At this time, in order to allow the antibacterial agent to be uniformly present on the surface of the fiber or the molded product and to exhibit good antibacterial properties, it is necessary to refine the masterbatch.

  In order to develop excellent antibacterial properties even with a small amount of antibacterial agent, the resin used for the masterbatch is preferably a thermoplastic resin. When the thermoplastic resin is used and melt-mixed with the synthetic resin, the antibacterial composite particles are rapidly melted and melt-mixed into the product resin, and as a result, the antibacterial agent is uniformly dispersed. The antibacterial molded article of the present invention can exhibit a sufficient antibacterial effect without impairing the original characteristics of the material by containing the antibacterial agent uniformly.

<Antimicrobial composite particles>
First, the antibacterial composite particles of the present invention will be described. That is, the present invention is an antibacterial composite particle in which an inorganic antibacterial agent is dispersed in a resin, the antibacterial inorganic particle A having silver or silver ions and having a hydrophobicity of 20% or less, and a hydrophobicity of 30. %, And antibacterial inorganic particles B having a volume average particle size of 0.01 to 3 μm.

  As the antibacterial inorganic particles A, inorganic particles having a volume average particle diameter of 0.02 μm or more and 5 μm or less are used as described later, and the antibacterial inorganic particles B have a volume average particle diameter of 0.01 μm or more and 3 μm or less. Therefore, an antibacterial agent smaller than the inorganic antibacterial agent is used.

  The antibacterial inorganic particles (hereinafter referred to as “antibacterial inorganic particles”) are blended together with a resin to produce antibacterial composite particles, and then the antibacterial composite particles and the base resin are melted to form a resin molded body. When manufacturing and fibers, the antibacterial inorganic particles in the antibacterial composite particles use multiple antibacterial agents with different particle sizes, so that the antibacterial effect is maintained without dropping from the surface of the molded body during manufacturing and repeated use can do.

  Furthermore, the inorganic antibacterial agent of the present invention can relieve the antibacterial inhibitory action which has been a problem of silver antibacterial agents, and can exhibit sufficient antibacterial properties in resin molded bodies and fibers.

(Antimicrobial inorganic particles A)
The average volume particle size of the antibacterial inorganic particles containing silver and silver ions is preferably 0.02 to 5 μm, more preferably 0.04 to 2 μm, and most preferably 0.05 to 1 μm. When the average volume particle size is less than 0.02 μm, it becomes impossible to sufficiently support silver and silver ions, and when the resin molded body and fiber are produced by melting the antibacterial composite particles and the base resin, the resin molded body and fiber Insufficient antibacterial properties cannot be expressed. In addition, the particle size is too small and the antibacterial inorganic particles soar, which tends to make handling difficult. On the other hand, when the volume average diameter of the inorganic antibacterial agent having silver and silver ions exceeds 5 μm, the resin molded body or fiber is produced when the antibacterial composite particles and the base resin are melted to produce a resin molded body or fiber. The antibacterial agent falls off from the surface, and sufficient antibacterial properties cannot be expressed. Furthermore, if the average volume particle diameter exceeds 5 μm, the surface area of the carrier per unit weight decreases, and the amount of antibacterial metal that can be supported on the antibacterial inorganic particles decreases, so the addition amount of the antibacterial inorganic particles must be increased. There is a tendency to adversely affect the physical properties of the resin molded body.

  Here, the average volume particle size was calculated by calculating the particle size distribution D50 from the light scattering intensity by dispersing antibacterial fine particles in water using a light scattering particle size distribution measuring device LB550 (manufactured by Horiba Seisakusho).

  The antibacterial inorganic particles A containing silver and silver ions are preferably composed of the silver and silver ions and an inorganic carrier, but are not limited to such a structure, such as the silver and silver ions. You may be comprised with an antibacterial metal simple substance. However, when the antibacterial inorganic particles A are composed of an antibacterial metal and an inorganic carrier, the antibacterial function is maintained because the dissolution of the metal is significantly less than when the antibacterial metal or its compound is used alone. It has the advantages of high safety and less discoloration due to sunlight.

  Further, when the antibacterial metal is used, examples of the inorganic carrier on which the antibacterial metal is supported include at least one ceramic of alumina, silica, zeolite, phosphate compound, calcium carbonate, calcium silicate, bentonite, and titanium oxide. be able to. These ceramics are safe for the human body and can stably carry an antibacterial metal.

  More specifically, as antibacterial inorganic particles A, considering safety to the human body, strength of antibacterial power, durability of antibacterial performance, etc., silver metal and silver ions are converted into calcium phosphate, aluminum phosphate, zirconium phosphate, It is preferable to combine with one or more carriers of magnesium phosphate, barium phosphate, zinc phosphate and hydroxyapatite. The most preferred combination is a carrier in which silver is supported on calcium phosphate. In this case, the combination of calcium phosphate and silver has the advantage that a strong adhesion between the carrier and the metal can be obtained.

  The antibacterial inorganic particles A when the antibacterial metal is supported on the inorganic carrier can be obtained by supporting the antibacterial metal on the inorganic carrier by a conventional method. Examples of conventional methods include physical adsorption, chemical adsorption, ion exchange, vapor deposition, surface thin film formation, and mechanical support.

  The antibacterial inorganic particles A preferably have a degree of hydrophobicity of 0% to 20%, more preferably 10% to 20%. If the degree of hydrophobicity exceeds 20%, the antibacterial action of silver or silver ions against hydrophilic bacteria may be reduced, and desired antibacterial properties may not be obtained.

  Examples of the method for adjusting the degree of hydrophobicity of the antibacterial inorganic particles A within the above range include surface treatment with a surface treatment agent containing at least one of Si, Al, and Ti. As said surface treating agent, a silane coupling agent, an aluminate coupling agent, a titanate coupling agent etc. are mentioned, for example.

  As the surface treatment method, for example, supported inorganic particles carrying silver or silver ions and the surface treatment agent are added to a solvent such as water or alcohol, hexane, toluene, ethyl acetate, methyl ethyl ketone (MEK). An example of the method is to dry the surface-supported inorganic supported particles after the dispersion and further heat the coating as necessary to firmly fix the coating on the surface of the inorganic supported particles.

(Antimicrobial inorganic particles B)
The antibacterial agent used in combination with the antibacterial agent having silver and silver ions preferably has a volume average diameter of 0.01 to 3 μm.

When the volume average particle size is less than 0.01 μm, it is not possible to effectively dispose the antibacterial agent on the resin body or fiber surface when the antibacterial composite particles and the base resin are melted to produce a resin molded body or fiber. Sufficient antibacterial properties cannot be expressed in the resin composite or fiber. On the other hand, when the volume average diameter of the antibacterial agent used in combination with the antibacterial agent having silver and silver ions exceeds 3 μm, the resin is produced when the antibacterial composite particles and the base resin are melted to produce a resin molded body or fiber. There is a possibility that the antibacterial agent may fall off from the surface of the molded body or fiber, so that sufficient antibacterial properties cannot be expressed.

  The antibacterial agent used in combination with the antibacterial agent having silver and silver ions is desirably an oxide containing at least Zn, Ti, Cu, and Ni. Since the surface treatment agent and the surface treatment method are the same as described above, the description thereof is omitted here.

  The degree of hydrophobicity of the antibacterial inorganic particles B is preferably 30% or more and 100% or less. When the degree of hydrophobicity is less than 30%, the antibacterial activity cannot be sufficiently improved by the combined use with the antibacterial inorganic particles A. In addition, when the antibacterial composite particles and the base resin are melted to produce a resin molded body or fiber, the antibacterial inorganic particles B drop off from the surface of the resin molded body or fiber and sufficient antibacterial properties cannot be expressed. there is a possibility.

  The ratio of the addition amount of the antibacterial inorganic particles A and the antibacterial inorganic particles B is preferably 1: 7 to 1: 0.25, and more preferably 1: 4 to 1: 0.25. If it exceeds 1: 7, the strong antibacterial effect of silver and silver ions is reduced, and it becomes impossible to give a sufficient antibacterial effect to the resin molded body and fiber. On the other hand, when the ratio is less than 1: 0.25, the effect of the antibacterial metal oxide on the anti-antagonist is reduced, and a sufficient antibacterial effect cannot be imparted to the resin molded body or fiber.

  The reason why the antibacterial ability is remarkably improved when the antibacterial inorganic fine particles A and the antibacterial inorganic fine particles B having a degree of hydrophobicity within the specified range of the present application are used in combination is considered as follows. Bacterial cells gather around the antibacterial inorganic particles A having a low degree of hydrophobicity, and silver and silver ions are taken into the cells to destroy and sterilize the cell walls of the cells. At this time, if the inorganic antibacterial agent B having a high degree of hydrophobicity is present in the vicinity, the active oxygen generated in the vicinity activates silver in the inorganic antibacterial agent A, and accelerates silver uptake.

  Here, the inorganic antibacterial agent B is considered to give a pseudo catalytic action to the inorganic antibacterial agent A. When the inorganic antibacterial agent B is appropriately hydrophobized as defined in the present invention, before the electrons and holes generated by excitation are recombined, charge exchange with the metal can be performed. Antibacterial activity is thought to increase. That is, since the recombination is affected by surrounding moisture, it is desirable that the inorganic fine particles B have a high degree of hydrophobicity.

  The blending amount of the antibacterial composite particles in the base resin depends on the amount of the antibacterial inorganic particles A and B contained in the antibacterial composite particles, and the total concentration of the antibacterial inorganic particles A and B in the base resin is The amount is 0.01 to 30 wt%, preferably 0.05 to 20 wt%. When the concentration of the antibacterial inorganic particles in the resin molded body is less than 0.01 wt%, the antibacterial property does not appear in the resin molded body, and even if it exceeds 30 wt%, the improvement of the antibacterial performance compared to the case of 30 wt% or less unacceptable. Therefore, in order to maximize the antibacterial performance at a low cost, the antibacterial composite particles are blended in the resin molded body so that the concentration of the antibacterial inorganic particles in the resin molded body is 0.01 to 30 wt%. It is preferable to do.

  The total content of the antibacterial inorganic particles A and the antibacterial inorganic particles B contained in the antibacterial composite particles is not particularly limited as long as the desired antibacterial performance can be imparted to the antibacterial composite particles. It is preferable that it is the range of% -60 weight%. Addition of antibacterial composite particles to the base resin in order to exert the necessary antibacterial function when the total content of the antibacterial inorganic particles A and B in the antibacterial composite particles is less than 0.1% by weight Since the amount increases, the production cost of the antibacterial resin molding tends to increase. If the total content of the antibacterial inorganic particles A and B exceeds 60% by weight, the antibacterial inorganic particles A and B tend to aggregate, and kneading at the time of manufacturing the antibacterial composite particles tends to be difficult. .

  In consideration of maintaining higher antibacterial properties and productivity and manufacturing cost in the antibacterial composite particles, the antibacterial inorganic particles A having silver or silver ions and the antibacterial property containing oxides of copper or zinc A combination with inorganic particles B is most preferred. By setting it as the said structure, when antibacterial composite particle and shaping | molding base resin are melt-kneaded, it is hard to isolate | separate from the master resin mentioned later, and these antibacterial inorganic particles A and B are made into the resin molding and the surface layer of a fiber. Can concentrate enough. For this reason, the antibacterial performance of the base resin can be sufficiently improved with a smaller amount of the antibacterial inorganic particles A and B. The oxide of the antibacterial inorganic particles B may be used alone, but a plurality of types may be mixed and a plurality of types of alloys may be used.

  The degree of hydrophobicity of the antibacterial inorganic particles B is desirably higher than that of the antibacterial inorganic particles A having silver and silver ions. In general, antibacterial agents containing silver and silver ions may cause undesired aggregation when dispersed in resins that have a low hydrophobicity and have polar groups in the resin, making it difficult to stably develop antibacterial properties. There was a case. As a result, it was difficult for the antibacterial agent to uniformly exist on the molded body and the fiber surface, and it was difficult to obtain a good antibacterial effect. On the other hand, the small-diameter antibacterial inorganic particles B having high hydrophobicity are good for a resin having a polar group to a nonpolar resin, and also for a resin obtained by blending a polar resin and a nonpolar resin. It becomes possible to show dispersion and to exhibit stable antibacterial performance.

  Here, the degree of hydrophobicity was measured by the methanol hydrophobization method.

  The degree of hydrophobicity of the antibacterial inorganic particles A and B was calculated based on the following formula.

  Hydrophobicity (%) = (Methanol concentration 1 (%) + Methanol concentration 2 (%)) / 2

  In the above formula, “methanol concentration 1” means that when an antibacterial agent is put into an aqueous methanol solution, the methanol concentration in the aqueous methanol solution when a part of the antibacterial agent starts to settle and cause suspension (unit: Volume%). “Methanol concentration 2” means the concentration of methanol in the aqueous methanol solution when the antibacterial agent is put into the aqueous methanol solution and the resin powder suspends without floating on the liquid surface (unit: volume). %) Is the lowest methanol concentration. When the aqueous methanol solution is not suspended, the antibacterial agent floats on the surface of the water, and when it begins to suspend, some of the resin-containing particles begin to sink below the surface of the water, and when suspended, the resin-containing particles completely sink below the surface of the water. It becomes cloudy.

  The methanol concentrations 1 and 2 can be obtained, for example, as follows. That is, first, a plurality of beakers are prepared, and 60 ml of a plurality of methanol aqueous solutions having different concentrations every 10% from 0 to 100% are put into these beakers. Then, 0.1 g of resin powder is added to each aqueous solution, lightly stirred with a magnetic stirrer, and the aqueous solution in the beaker is observed. From these observation results, after determining the range including “methanol concentration 1” and the range including “methanol concentration 2”, methanol aqueous solutions having different concentrations every 10% in each range were prepared as described above. The methanol aqueous solution is observed to obtain “methanol concentration 1” and “methanol concentration 2”. Table 1 shows measurement examples of methanol concentration and observation results. In Table 1, ◯, Δ, and x are described according to the following criteria.

○ All resin-containing particles float △ Some resin-containing particles are suspended × All resin-containing particles are suspended

  From the results shown in Table 1, it can be seen that “methanol concentration 1” is included in the range of 10 to 20%, and “methanol concentration 2” is included in the range of 20 to 30%.

[Master resin for antibacterial composite particles]
The resin constituting the antibacterial composite particles is preferably a thermoplastic resin. After the antibacterial inorganic particles A and B are blended to produce antibacterial composite particles, the antibacterial composite particles and the base resin are melted to produce a resin molded body or fiber. The active inorganic particles A and B can be effectively diffused and permeated in the base resin, and the antibacterial inorganic particles can be sufficiently concentrated on the surface layer of the resulting molded resin or fiber. For this reason, it is because sufficient antibacterial property can be expressed to a resin molding and a fiber with a small amount of antibacterial inorganic particles A and B.

  The “master resin” which is a resin constituting the antibacterial composite particles of the present invention described above will be described below.

  The master resin of the present invention is blended with the antibacterial composite particles together with the antibacterial inorganic particles A and B.

  Examples of the master resin include styrenes such as styrene and chlorostyrene, monoolefins such as ethylene, propylene, butylene, and isoprene, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, and vinyl butyrate, and acrylic. Α-methylene aliphatic monocarboxylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate Homopolymers or copolymers such as vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl butyl ether, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, vinyl isopropenyl ketone, etc. That. Master resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer, polyethylene. And polypropylene.

  Furthermore, examples of the master resin include polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, and paraffin wax.

  Specific examples of the polyester include polyethylene terephthalate, polybutylene terephthalate, poly (ethylene terephthalate / isophthalate), poly (ethylene glycol / cyclohexanedimethanol / terephthalate), polycarbonate, and polyarylate.

  Specific examples of the polyamide include nylon 4, nylon 6, nylon 12, nylon 66, and nylon 610.

  Examples of the master resin include polyamide, acrylic, fluororesin, and resins derived from these.

  Among the above master resins, polyester, polyamide, polystyrene, and styrene acrylic resin are particularly preferable in view of ease of blending, dispersibility, and versatility of the antibacterial inorganic particles A and B. Among them, the antibacterial inorganic particles are well dispersed. Polyester or styrene acrylic resin is more preferable because it can be made difficult to affect the resin molding and yarn properties.

  When the antibacterial composite particles are applied to fibers, polyesters, polyamides, and the like are suitable among the master resins in consideration of yarn stretchability.

[Manufacturing method of master resin]
Next, an embodiment of a method for producing a master resin according to the present invention will be described.

  First, the case where the master resin is a polyester resin will be described as an example.

  First, an acid and an alcohol are subjected to a polymerization reaction (polymerization reaction step). As the acid, a monomer that is a raw material of the above-described master resin is used. Specifically, terephthalic acid, fumaric acid, maleic acid, succinic acid, trimellitic acid, pyromellitic acid and the like are used. The alcohol is not particularly limited as long as it can be polymerized with the acid to form a polyester resin. Examples of the alcohol include bisphenol A, bisphenol A alkylene oxides, glycerin, cyclohexanedimethanol, butanediol, Etc.

  In addition, when manufacturing master resin comprised with a styrene acrylic resin, an acid may be replaced with acrylic acid and alcohol may be replaced with styrene.

  The antibacterial composite particles preferably have a volume average particle size of 1 to 2000 μm, more preferably 5 to 1000 μm. If the volume average particle size of the antibacterial composite particles is less than 1 μm, there is a tendency for poor handling properties such as generation of dust and excessive increase in pulverization cost, and if it exceeds 2000 μm, sufficient with other additives used together There is a tendency that mixing cannot be obtained.

  When the base resin is a synthetic resin, the volume average particle diameter of the antibacterial composite particles is preferably 10 to 2000 μm. When the base resin is a synthetic fiber or a nonwoven fabric, the volume average particle diameter of the antibacterial composite particles is 1 to 1000 μm. Preferably, when the base resin is synthetic paper, the antibacterial composite particles preferably have a volume average particle size of 1 to 1000 μm. Furthermore, in the case of an antibacterial coating material in which antibacterial composite particles are dispersed in the coating composition, the volume average particle size of the antibacterial composite particles is preferably 1 to 100 μm.

  If necessary, the antibacterial composite particles can be blended with one or more known additives in a range that does not affect the antibacterial composite particles. Examples of such additives include flame retardants, flame retardant aids, preservatives, antifungal agents, antioxidants, ultraviolet absorbers, mold release agents, plasticizers, surfactants, dispersants, lubricants, and colorants. (Dye and pigment), fillers, binders, charge control agents and the like. These additives can be blended at any point in the process until the master resin and the antibacterial inorganic particles are crushed. However, in the antibacterial composite particles, a lubricant, a dispersant, a dispersion aid and the like that are generally used for improving the compatibility between the resin and the antibacterial inorganic particles are not necessarily required.

  Specific applications of the antibacterial composite particles include various packaging materials such as packaging films, air conditioner filters, water purifier filters, cutting boards, refrigerator interiors, medical instruments, various tubes, packings, food containers, etc. Various resin moldings are mentioned, and according to the antibacterial composite particles, it is possible to impart durable and good antibacterial properties to the resin moldings.

[Method for producing antibacterial composite particles]
The antibacterial composite particles can be obtained by a melt-kneading pulverization method in which various parameters are controlled in consideration of the characteristics of the master resin and the antibacterial inorganic particles A and B.

The thermoplastic resin and the antibacterial inorganic particles A and B may be mixed by a Henschel mixer, a super mixer, or the like before melt kneading because of pre-dispersibility before melt kneading and grinding of coarse raw material particles. preferable. At this time, the capacity of the stirrer, the rotation speed of the stirrer, the stirring time, and the like must be selected in an appropriate combination. Taking an example of a Henschel mixer, which is a stirrer having a stirrer capacity of 75 liters, the rotation speed is preferably 500 rpm or more. When the rotational speed is less than 500 rpm, a long time of stirring is required to obtain sufficient stirring, and the operation becomes inefficient. The upper limit of the rotational speed depends on the performance of the apparatus, the stirring time, and the resin characteristics. The stirring time is preferably 15 seconds to 15 minutes, depending on the rotational speed of the stirring device. When the stirring time is less than 15 seconds, stirring is insufficient, antibacterial inorganic particles are likely to be unevenly distributed in the antibacterial composite particles, and aggregation of the antibacterial inorganic particles is likely to occur. On the other hand, if the stirring time exceeds 15 minutes, the stirring effect does not improve, but the master resin and the antibacterial inorganic particles may be re-separated to reduce the stirring effect. Furthermore, the temperature rises and may cause aggregation.

  After stirring the master resin and the antibacterial inorganic particles A and B in this way to obtain a stirred product, the stirred product is kneaded in a molten state by a known method.

  At this time, from the viewpoint of improving the dispersibility of the antibacterial inorganic particles A and B, it is preferable to perform melt-kneading using a kneading apparatus such as a single-screw or multi-screw extruder. At this time, the number of kneading screw zones, the cylinder temperature, the kneading speed, etc. of the kneading apparatus have a great influence on the physical properties of the antibacterial composite particles to be produced. Therefore, it is necessary to set and control them all at appropriate values. is there. For example, it is necessary to control the apparatus so that the resin temperature is appropriate in accordance with the physical properties of the master resin, and in order to obtain a sufficient kneading state, the number of kneading screw zones and the kneading speed are comprehensively determined. Must be decided. Among the control factors at the time of kneading, the number of kneading machine rotations, the number of kneading screw zones, and the set temperature of the cylinders have a particularly great influence on the kneading state.

  The number of rotations varies depending on the resin, but generally 300 to 1,000 rpm is desirable, and the number of kneading screw zones is better kneaded using a multi-stage zone such as a two-stage screw than a one-stage screw. The cylinder set temperature is determined from the softening temperature of the master resin, and is usually preferably set to -20 to + 100 ° C rather than the softening temperature. Below these, sufficient kneading and dispersion cannot be obtained, and aggregation of antibacterial inorganic particles is likely to occur, and when above these, kneading share is not applied, so not only sufficient dispersion is obtained, but also after kneading. Cooling may be difficult.

  The kneaded product obtained by melt-kneading is sufficiently cooled and then pulverized by a known method such as a mechanical pulverization method such as a ball mill, a sand mill, or a hammer mill, or an airflow pulverization method. If cooling by a conventional method is not sufficient, a cooling or freeze pulverization method can also be selected. It is necessary to select a cooling method and a pulverization method suitable for the properties of the object to be pulverized, which are also antibacterial composite particles, and to optimize the cooling temperature, pulverization pressure, pulverization temperature, air flow velocity, and the like.

[Resin molding]
The resin molding includes the antibacterial composite particles and a molding base resin.

  The molding base resin is not particularly limited, and the selection depends on the application. Particularly suitable resins are polyamide, polyester, polyolefin, ABS, AS, acrylic resin, acrylonitrile, polyvinyl alcohol, polystyrene, butadiene resin, polyvinyl chloride resin, polyvinyl acetate resin, polyacetal, melamine, epoxy resin, urethane, It is a thermoplastic resin such as phenol, polycarbonate, or fluororesin.

  The compounding amount of the antibacterial composite particles in the resin molded body depends on the amount of the antibacterial inorganic particles contained in the antibacterial composite particles, and the concentration of the antibacterial inorganic particles in the resin molded body is 0.01 to 30 wt%, The amount is preferably 0.05 to 20 wt%. When the concentration of the antibacterial inorganic particles in the resin molded body is less than 0.01 wt%, the antibacterial property does not appear in the resin molded body, and even if it exceeds 30 wt%, the improvement of the antibacterial performance compared to the case of 30 wt% or less unacceptable. Therefore, in order to maximize the antibacterial performance at a low cost, the antibacterial composite particles are blended in the resin molded body so that the concentration of the antibacterial inorganic particles in the resin molded body is 0.01 to 30 wt%. It is preferable to do.

[Production method of resin molding]
The resin molded body can be produced by a master batch method, a colored pellet method, or a dry color method. The master batch method is a method in which master pellets (antibacterial composite particles) formed by melting and extruding a master resin, antibacterial inorganic particles, a dispersant and the like are prepared and mixed with a molding base resin to be molded. The colored pellet method is a method of molding using pellets extruded with the same composition as the final product such as antibacterial composite particles, molded base resin, colorant, dispersant, etc. The dry color method is antibacterial In this method, a dry color mixed with composite particles, a dispersant, metal soap, wax, and the like is mixed with a molding base resin and molded. In general, the master batch method is widely used.

  Examples of the molding process include known methods such as injection molding, extrusion molding, blow molding, inflation molding, and vacuum molding.

  In any of the above production methods, molding is performed using antibacterial composite particles and a molded base resin. At this time, when the antibacterial composite particle containing the master resin of the present invention is used as the antibacterial composite particle, the antibacterial inorganic particle and the master resin are not separated during the molding process. Can be effectively diffused and permeated (bleeded out) in the molding base resin, and the antibacterial inorganic particles can be sufficiently concentrated on the surface layer of the molded resin. For this reason, sufficient antibacterial property can be expressed in the resin molding with a small amount of antibacterial inorganic particles.

  At this time, it is preferable that the softening temperature of the molding base resin is higher than the softening temperature of the antibacterial master resin constituting the antibacterial composite particles. In this case, when the resin molded body is molded, the master resin contained in the antibacterial composite particles is softened earlier than the molded base resin by the heat during molding and easily bleeds out on the surface of the resin molded body. For this reason, the antibacterial agent density | concentration in a resin molding can be raised more only in a surface layer, and the antibacterial property on the surface of a resin molding can be improved more fully by addition of a small amount.

  The resin molded body obtained in this way is polished on the surface of the resin molded body as it continues to be used. Even in this case, a new surface appears, and a new antibacterial agent is present there. In addition, since the bleed-out phenomenon gradually occurs even during continuous use, effective antibacterial properties are maintained over a long period of time in the resin molded body.

[Antimicrobial fiber]
The antibacterial fiber includes the antibacterial composite particle of the present invention and a fiber base resin.

  The fiber base resin is not particularly limited, and examples of the fiber base resin include polyamides such as nylon 6 and nylon 66, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and polyarylate, polyethylene, and polypropylene. Polyolefin resins such as polymethylpentene and polybutene, acrylic resins such as acrylonitrile-butadiene-styrene (ABS) resin, acrylonitrile-styrene (AS) resin, methacrylic resin, acrylonitrile, polyvinyl alcohol, polystyrene resin, butadiene resin, Polyvinyl chloride resin, polyvinyl acetate resin, polyacetal resin, polyamide resin, melamine resin, epoxy resin, urethane resin, phenol resin, polycarbonate, fluorine resin Etc., or it may be mentioned synthetic resin and semi-synthetic resin such as a mixture thereof. Among these, a particularly preferable fiber base resin is a polystyrene resin, an acrylic resin, a polyolefin resin, or a mixture thereof. As the fiber base resin, the above resins may be used alone or in combination of two or more.

  The blending amount of the antibacterial composite particles in the antibacterial fiber is determined by the blending amount of the antibacterial inorganic particles, and the concentration of the antibacterial inorganic particles in the antibacterial fiber is 0.01 to 20 wt%, preferably 0.01 to 10 wt%. This is the amount. When the content of the antibacterial inorganic particles in the antibacterial fiber is less than 0.01 wt%, the antibacterial property does not appear in the antibacterial fiber, and even when the content exceeds 20 wt%, the antibacterial performance is less than that of 20 wt% or less. The improvement is not recognized. Therefore, in order to maximize the antibacterial performance at a low cost in the antibacterial fiber, the content of the antibacterial inorganic particles in the antibacterial fiber is preferably 0.01 to 20 wt%.

[Production method of antibacterial fiber]
The antibacterial fibers can be obtained by blending and spinning the antibacterial composite particles in the fiber base resin at any stage until the fiber base resin is discharged from the spinneret. . In this case, antibacterial fibers having sufficient antibacterial performance can be obtained without impairing the original characteristics of the material. The antibacterial composite particles can be blended into the fiber base resin by a conventional method such as mixing with polymer pellets or spinning dope.

  From the antibacterial fibers obtained as described above, filament yarns, spun yarns, woven and knitted fabrics and nonwoven fabrics can be produced. These antibacterial fibers are used for clothing such as outerwear, underwear, and work clothes. , Shoe insoles, socks, rags, socks, toys, paints, futons, beds, carpets, lab coats, sick clothes, bandages, gauze, toothbrushes and the like.

  Hereinafter, the contents of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In the following description, “part” represents “part by weight” unless otherwise specified. In Examples and Comparative Examples, the glass transition temperature (hereinafter referred to as “Tg”) and softening temperature of the master resin, the measurement of the amount of water in the antibacterial inorganic particles, and the measurement method of the antibacterial performance are as follows. It was measured.

(Measurement method of antibacterial performance)
The antibacterial performance of the test piece as a resin molding was measured according to the following implementation procedures (1) to (5).

(1) Suspend test bacteria (E. coli, Staphylococcus aureus) cultured on a slope medium of ordinary agar in water to prepare a suspension with a bacterial concentration of 2.0 × 10 ⁵ .

(2) 0.5 ml of the above suspension is dropped onto the surface of a test piece that is placed in a petri dish, covered with a plastic film, and then kept at a humidity of 90% and a temperature of 35 ± 1 ° C. for 24 hours. Culture the test bacteria.

(3) After culturing for 24 hours, the cells are washed out from the surface of the test piece with a medium solution (for example, SCDLP medium).

(4) After diluting the washing solution with physiological saline to an appropriate magnification, this is mixed with the medium solution and cultured at a temperature of 35 ± 1 ° C. for 40 to 48 hours using a standard agar medium.

(5) After culture, the number of colonies generated in the medium is counted, and the number of obtained colonies is multiplied by the dilution factor to obtain the number of viable bacteria.

  In addition to the steps (1) to (5), in order to confirm the reliability of the test, the antibacterial inorganic particles A and B added (reference) were measured. The measurement method was the same as in the case of adding antibacterial inorganic particles.

(Calculation method of antibacterial activity value)
The antibacterial activity value was calculated based on the following formula.

Antibacterial activity value = Log (Y / X) (I)
(In the above formula, X represents the number of viable bacteria in the test piece, and Y represents the number of viable bacteria in the test piece to which no antibacterial inorganic particles were added for comparison)

  The antibacterial property was determined according to the following criteria.

  That is, when any of the antibacterial activity values of Escherichia coli and Staphylococcus aureus is less than 2.0, antibacterial activity is not recognized in the resin molding, and both of Escherichia coli and Staphylococcus aureus have antibacterial activity. When the value was 2.0 or more, antibacterial properties were recognized.

<Example 1>
Polyester resin (as monomer, ethylene oxide adduct of bisphenol A / terephthalic acid / fumaric acid polycondensation resin; number average molecular weight 4.5 × 10 ³ , weight average molecular weight 1.5 × 10 ⁴ , acid value = 15 mg / KOH, softening temperature: 100 ° C., Tg: 65 ° C., 80 wt%, antibacterial inorganic particles A, inorganic particles in which silver metal is supported on tricalcium phosphate (volume average particle diameter D50 = 0.1 μm, containing silver) 1.3%) 10% by weight, 10% by weight of zinc oxide inorganic particles (volume average diameter D50 = 0.05 μm) surface-treated with octyltrimethoxysilane as antibacterial inorganic particles B, Henschel mixer (FM-75 type) , Manufactured by Mitsui Miike Chemical Co., Ltd.) and mixed at 1000 rpm for 2 minutes. After that, using an extruder (TEM48BS, manufactured by Toshiba Machine Co., Ltd.), the kneaded material melted and kneaded at a screw rotation speed of 500 rpm and a cylinder temperature of 80 ° C. is cooled and then pulverized by a hammer mill to have an antibacterial composite having a volume average particle size of about 300 μm. Particles were obtained.

  Twin screw extrusion in which 90% by weight of NaCl-containing acrylonitrile-butadiene-styrene copolymer (NaCl addition concentration in ABS resin = 2%) and 10% by weight of the antibacterial composite particles are mixed well and the cylinder temperature is set to 260 ° C. An antibacterial agent-containing pellet was obtained by melt kneading at a rotation speed of 300 rpm using a machine (ZSK-25 manufactured by Toshiba Machine Co., Ltd.). The pellets were formed by an injection molding machine (model “M-50AII-DM” manufactured by Meiki Seisakusho Co., Ltd.) at a cylinder temperature of 240 ° C., a screw rotation speed of 80 rpm, an injection speed of 10 seconds, and a mold temperature of 250 ° C. A test piece (A) was obtained which was injection-molded to obtain a flat plate for antibacterial evaluation of 5 cm × 5 cm × 2 mm.

  As the antibacterial activity value of the test piece (A), Escherichia coli = 3.6 and Staphylococcus aureus = 2.8 had sufficient antibacterial properties. In addition, the appearance of the molded body was good with no occurrence of silver streaks, cracks, burns or discoloration. Further, no discoloration of the test piece (A) was observed in the light resistance test (xenon arc Ci65 (ATLAS), irradiation illuminance: 0.35 W2 / mat 340 nm, 1 week).

<Comparative Example 1>
Polyester resin (as monomer, ethylene oxide adduct of bisphenol A / terephthalic acid / fumaric acid polycondensation resin; number average molecular weight 4.5 × 10 ³ , weight average molecular weight 1.5 × 10 ⁴ , acid value = 15 mg / KOH, softening temperature: 100 ° C., Tg: 65 ° C. 80% by weight, inorganic particles in which silver metal is supported on tricalcium phosphate as antibacterial particles (volume average particle diameter D50 = 0.1 μm, silver content 1) .3%) 20% by weight was charged into a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) and mixed at 1000 rpm for 2 minutes. After that, using an extruder (TEM48BS, manufactured by Toshiba Machine Co., Ltd.), the kneaded material melted and kneaded at a screw rotation speed of 500 rpm and a cylinder temperature of 80 ° C. is cooled and then pulverized by a hammer mill to have an antibacterial composite having a volume average particle size of about 300 μm. Particles were obtained.

  Twin screw extrusion in which 90% by weight of NaCl-containing acrylonitrile-butadiene-styrene copolymer (NaCl addition concentration in ABS resin = 2%) and 10% by weight of the antibacterial composite particles were mixed well and the cylinder temperature was set at 260 ° C. An antibacterial agent-containing pellet was obtained by melt kneading at a rotation speed of 300 rpm using a machine (ZSK-25 manufactured by Toshiba Machine Co., Ltd.). The pellets were formed by an injection molding machine (model “M-50AII-DM” manufactured by Meiki Seisakusho Co., Ltd.) at a cylinder temperature of 240 ° C., a screw rotation speed of 80 rpm, an injection speed of 10 seconds, and a mold temperature of 250 ° C. A test piece (B) was obtained by injection molding to obtain a 5 cm × 5 cm × 2 mm antibacterial evaluation flat plate.

  The antibacterial activity value of the test piece (B) was Escherichia coli = 1.1, Staphylococcus aureus = 1.5, and the antibacterial property was not sufficient. Moreover, yellowing of the molded object which evaluated the test piece (B) by the light resistance test (Xenon arc Ci65 (ATLAS), irradiation illumination intensity: 0.35W2 / mat340nm, 1 week) was seen.

<Comparative example 2>
Antibacterial composite particles were obtained in the same manner as in Comparative Example 1 except that the following were used as the antibacterial inorganic particles A used in Example 1. Antibacterial inorganic particles A = inorganic particles obtained by supporting silver metal on zirconium phosphate (volume average particle diameter D50 = 7.1 μm, silver content 1.8%). This antibacterial composite particle was added to NaCl-containing acrylonitrile-butadiene-styrene copolymer in the same manner as in Example 1 to prepare a test piece (C). The antibacterial activity values of the test piece (C) were E. coli = 2.3 and S. aureus = 1.9, and the antibacterial activity was not sufficient. In addition, silver streaks and cracks occurred in the appearance of the molded body.

<Example 2>
Polyethylene terephthalate resin with halogenated flame retardant (IV viscosity = 0.66, flame retardant = Fireguard R2000: manufactured by Teijin Kasei Co., Ltd., 1% added) and 90% by weight on the surface of the antibacterial inorganic particles B Except for the surface treatment with methoxysilane, 10% by weight of the antibacterial composite particles produced in the same manner as in Example 1 was charged into a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) and mixed at 1000 rpm for 2 minutes. The mixture was kneaded and pelletized with a twin-screw extruder (Berstorf, φ = 43, L / D = 37) at a cylinder temperature of 260 ° C. and a screw rotation speed of 100 rpm to produce a master chip. The master chip was melt-spun at a winding speed of 1200 m / min in accordance with a conventional method, and an antibacterial yarn was obtained using a spindle-type drawing false twister.

Antibacterial test method and antibacterial effect of textile products An antibacterial test was conducted in accordance with JIS L1902. In other words, 1.3 × 10 ⁵ cells / ml of the following test bacteria were prepared with a sterile 1/20 concentration broth, and 0.2 ml of the prepared bacteria solution was added to 0.4 g of each sample of Example 2. Are inoculated uniformly and cultured at 37 ° C. for 18 hours. After completion of the culture, the test bacteria are washed out, and the liquid is cultured at 37 ° C. for 24 to 48 hours by the pour plate agar culture method, and the viable cell count is measured. In addition, the antibacterial activity value computed by the method similar to an antibacterial resin using Staphylococcus aureus as a test microbe was 3.8, and showed sufficient antibacterial property.

  The tensile strength, elongation strength, boiling yield, and dry yield of the original yarn were all good and without problems.

<Comparative Example 3>
20% by weight of the antibacterial composite particles used in Comparative Example 1 were put into a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) and mixed at 1000 rpm for 2 minutes. The mixture was kneaded and pelletized with a twin-screw extruder (Berstorf, φ = 43, L / D = 37) at a cylinder temperature of 260 ° C. and a screw rotation speed of 100 rpm to produce a master chip. The master chip was melt-spun at a winding speed of 1200 m / min in accordance with a conventional method, and an antibacterial yarn was obtained using a spindle-type drawing false twister.

Antibacterial test method and antibacterial effect of textile products An antibacterial test was conducted in accordance with JIS L1902. In other words, 1.3 × 10 ⁵ cells / ml of the following test bacteria were prepared with a sterile 1/20 concentration broth, and 0.2 ml of the prepared bacteria solution was added to 0.4 g of each sample of Example 2. Are inoculated uniformly and cultured at 37 ° C. for 18 hours. After completion of the culture, the test bacteria are washed out, and the liquid is cultured at 37 ° C. for 24 to 48 hours by the pour plate agar culture method, and the viable cell count is measured. In addition, the antibacterial activity value computed by the method similar to an antibacterial resin using Staphylococcus aureus as a test microbe was 1.4, and antibacterial property was inadequate.

<Example 3>
The following surface-treated zinc oxide was used as zinc oxide.

Core material: ZnO average volume diameter D50 = 0.01 μm
Treatment agent: Decylsilane: KBM3103 (Shin-Etsu Chemical)

  The core material and the treatment agent were charged in a toluene solvent so that the amount of the treatment agent relative to the core material was 10%, and the slurry was sufficiently dried with a stirrer, and then the toluene was evaporated by a rotary evaporator to obtain a treated powder. It was transferred to a vat, dried at 120 ° C. for 2 hours, and then crushed and surface-treated antibacterial inorganic particles B were obtained. The volume average particle diameter D50 of the antibacterial agent after the surface treatment was 0.02 μm. The surface-treated antibacterial inorganic particles B and antibacterial inorganic particles A were prepared by supporting silver on zirconium phosphate (average volume particle diameter D50 = 0.15 μm, silver content 2.8%). A test piece (D) was prepared in the same manner as in Example 1 except that the inorganic particles A: B = 1: 7. As the antibacterial activity value of the test piece (D), Escherichia coli = 4.5 and Staphylococcus aureus = 3.5 had sufficient antibacterial properties. Also, there was no problem with the appearance of the molded body. No discoloration was observed after the light resistance test results.

<Example 4>
Styrene acrylic resin (styrene / methyl methacrylate copolymer / number average molecular weight 2.7 × 10 ³ , weight average molecular weight 5 × 10 ⁴ , acid value = 20 mg / KOH, softening temperature: 105 ° C., Tg: 65 ° C.) 80 weight %, Inorganic particles in which silver metal is supported on tricalcium phosphate surface-treated with dimethyltrimethoxysilane (KA22, manufactured by Shin-Etsu Chemical Co., Ltd.) as antibacterial inorganic particles A (average volume particle diameter D50 = 0.1 μm, containing silver) Amount 1.3%) 10% by weight, 10% by weight of zinc oxide inorganic particles (average volume diameter D50 = 0.05 μm) surface-treated with an aluminate coupling agent (Plenact AL-M Ajinomoto Co., Inc.) FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) and mixed at 1000 rpm for 2 minutes. After that, using an extruder (TEM48BS, manufactured by Toshiba Machine Co., Ltd.), the kneaded material melted and kneaded at a screw rotation speed of 500 rpm and a cylinder temperature of 80 ° C. is cooled and then pulverized by a hammer mill to have an antibacterial composite having a volume average particle size of about 300 μm. Particles were obtained.

A monomer mixture consisting of 96% by weight of acrylonitrile and 4% by weight of vinyl acetate was subjected to aqueous suspension polymerization using ammonium persulfate as an initiator to prepare a polyacrylonitrile-based polymer having a weight average molecular weight of 20 × 10 ⁴ . The obtained polymer was dissolved in dimethylformamide, and 10% by weight of the antibacterial composite particles was added to the polymer stock solution to prepare a spinning stock solution.

Subsequently, the spinning solution was discharged from a nozzle by a wet spinning method, coagulated in an aqueous dimethylformamide solution, washed with ion-exchanged water, and dimethylformamide was removed. Then, it extended | stretched 2 times under 100 degreeC moist heat, and was dried at 120 degreeC with the heater roller. The dried fiber was further heated through a superheated roller whose surface temperature was set to 170 ° C., twice dry heat drawing was performed, and after applying an oil agent, an antibacterial false twisted fiber was created by winding up with a heating roller. .

  Antibacterial test method and antibacterial effect of textile products An antibacterial test was conducted in accordance with JIS L1902. As a test bacterium, Staphylococcus aureus was used, and the antibacterial activity value calculated by the same method as that of the antibacterial resin was 4.3, indicating a sufficient antibacterial property.

<Example 5>
The following surface-treated titanium oxide was used as titanium (IV) oxide.

Core material: TiO ₂ average volume diameter D50 = 2 μm
Treatment agent: n-decyltrimethoxysilane: KBM3103 (Shin-Etsu Chemical)

  The core material and the treatment agent were charged in a toluene solvent so that the amount of the treatment agent relative to the core material was 10%, and the slurry was sufficiently dried with a stirrer, and then the toluene was evaporated by a rotary evaporator to obtain a treated powder. It was transferred to a vat, dried at 120 ° C. for 2 hours, and then crushed and surface-treated antibacterial inorganic particles B were obtained. The volume average particle diameter D50 of the antibacterial agent after the surface treatment was 3 μm. Antibacterial inorganic particles using the surface-treated antibacterial agent and antibacterial inorganic particles A in which silver is supported on zirconium phosphate (average volume particle diameter D50 = 0.15 μm, silver content 2.8%) A test piece (E) was prepared in the same manner as in Example 1 except that A: B = 1: 4. As the antibacterial activity value of the test piece (E), Escherichia coli = 3.6 and Staphylococcus aureus = 3.9 had sufficient antibacterial properties. Also, there was no problem with the appearance of the molded body. No discoloration was observed after the light resistance test results.

<Example 6>
The following surface-treated copper oxide was used as copper (II) oxide.

Core material: CuO average volume diameter D50 = 0.1 μm
Treatment agent: n-decyltrimethoxysilane: KBM3103 (Shin-Etsu Chemical)

  The core material and the treatment agent were charged in a toluene solvent so that the amount of the treatment agent relative to the core material was 10%, and the slurry was sufficiently dried with a stirrer, and then the toluene was evaporated by a rotary evaporator to obtain a treated powder. It was transferred to a vat, dried at 120 ° C. for 2 hours, and then crushed and surface-treated antibacterial inorganic particles B were obtained. The volume average particle diameter D50 of the antibacterial agent after the surface treatment was 0.2 μm. Antibacterial inorganic particles using the surface-treated antibacterial agent and antibacterial inorganic particles A in which silver is supported on zirconium phosphate (average volume particle diameter D50 = 0.15 μm, silver content 2.8%) A test piece (F) was prepared in the same manner as in Example 1 except that A: B = 1: 4. As the antibacterial activity value of the test piece (F), Escherichia coli = 4.5 and Staphylococcus aureus = 4.1 had sufficient antibacterial properties. Also, there was no problem with the appearance of the molded body. No discoloration was observed after the light resistance test results.

<Example 7>
The following surface-treated nickel oxide was used as nickel (II) oxide.

Core material: NiO average volume diameter D50 = 0.01 μm
Treatment agent: n-decyltrimethoxysilane: KBM3103 (Shin-Etsu Chemical)

  The core material and the treatment agent were charged in a toluene solvent so that the amount of the treatment agent relative to the core material was 10%, and the slurry was sufficiently dried with a stirrer, and then the toluene was evaporated by a rotary evaporator to obtain a treated powder. It was transferred to a vat, dried at 120 ° C. for 2 hours, and then crushed and surface-treated antibacterial inorganic particles B were obtained. The volume average particle diameter D50 of the antibacterial agent after the surface treatment was 0.02 μm. Antibacterial inorganic particles using the surface-treated antibacterial agent and antibacterial inorganic particles A in which silver is supported on zirconium phosphate (average volume particle diameter D50 = 0.15 μm, silver content 2.8%) A test piece (G) was prepared in the same manner as in Example 1 except that A: B = 1: 4. As the antibacterial activity value of the test piece (G), Escherichia coli = 4.3 and Staphylococcus aureus = 3.9 had sufficient antibacterial properties. Also, there was no problem with the appearance of the molded body. No discoloration was observed after the light resistance test results.

<Comparative example 4>
Polyester resin (as monomer, ethylene oxide adduct of bisphenol A / terephthalic acid / fumaric acid polycondensation resin; number average molecular weight 4.5 × 10 ³ , weight average molecular weight 1.5 × 10 ⁴ , acid value = 15 mg / KOH, softening temperature: 100 ° C., Tg: 65 ° C. 80% by weight, zinc oxide inorganic particles (volume average diameter D50 = 0.05 μm) 20% by weight as antibacterial particles, Henschel mixer (FM-75 type, Mitsui) Into the Miike Chemical Industries Co., Ltd.) and mixed at 1000 rpm for 2 minutes. After that, using an extruder (TEM48BS, manufactured by Toshiba Machine Co., Ltd.), the kneaded material melted and kneaded at a screw rotation speed of 500 rpm and a cylinder temperature of 80 ° C. is cooled and then pulverized by a hammer mill to have an antibacterial composite having a volume average particle size of about 300 μm. Particles were obtained.

  Twin screw extrusion in which 90% by weight of NaCl-containing acrylonitrile-butadiene-styrene copolymer (NaCl addition concentration in ABS resin = 2%) and 10% by weight of the antibacterial composite particles are mixed well and the cylinder temperature is set to 260 ° C. An antibacterial agent-containing pellet was obtained by melt kneading at a rotation speed of 300 rpm using a machine (ZSK-25 manufactured by Toshiba Machine Co., Ltd.). The pellets were formed by an injection molding machine (model “M-50AII-DM” manufactured by Meiki Seisakusho Co., Ltd.) at a cylinder temperature of 240 ° C., a screw rotation speed of 80 rpm, an injection speed of 10 seconds, and a mold temperature of 250 ° C. A test piece (H) obtained by injection molding to obtain a flat plate for antibacterial evaluation of 5 cm × 5 cm × 2 mm was produced.

  The antibacterial activity value of the test piece (H) was E. coli = 1.2, Staphylococcus aureus = 0.9, and the antibacterial activity was not sufficient. Moreover, the yellowing of the molded object which evaluated the test piece (H) by the light resistance test (Xenon arc Ci65 (ATLAS), irradiation illumination intensity: 0.35W2 / mat340nm, 1 week) was seen.

<Comparative Example 5>
Polyester resin (as monomer, ethylene oxide adduct of bisphenol A / terephthalic acid / fumaric acid polycondensation resin; number average molecular weight 4.5 × 10 ³ , weight average molecular weight 1.5 × 10 ⁴ , acid value = 15 mg / KOH, softening temperature: 100 ° C., Tg: 65 ° C. 80% by weight, as antibacterial particles, inorganic particles (volume average particle diameter D50 = volume average particle diameter D50 = supporting tricalcium phosphate hydrophobized with silicone oil) 20 wt% of 0.1 μm, silver content 1.3%) was put into a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) and mixed at 1000 rpm for 2 minutes. After that, using an extruder (TEM48BS, manufactured by Toshiba Machine Co., Ltd.), the kneaded material melted and kneaded at a screw rotation speed of 500 rpm and a cylinder temperature of 80 ° C. is cooled and then pulverized by a hammer mill to have an antibacterial composite having a volume average particle size of about 300 μm. Particles were obtained.

  Twin screw extrusion in which 90% by weight of NaCl-containing acrylonitrile-butadiene-styrene copolymer (NaCl addition concentration in ABS resin = 2%) and 10% by weight of the antibacterial composite particles were mixed well and the cylinder temperature was set at 260 ° C. An antibacterial agent-containing pellet was obtained by melt kneading at a rotation speed of 300 rpm using a machine (ZSK-25 manufactured by Toshiba Machine Co., Ltd.). The pellets were formed by an injection molding machine (model “M-50AII-DM” manufactured by Meiki Seisakusho Co., Ltd.) at a cylinder temperature of 240 ° C., a screw rotation speed of 80 rpm, an injection speed of 10 seconds, and a mold temperature of 250 ° C. A test piece (I) obtained by injection molding to obtain a flat plate for antibacterial evaluation of 5 cm × 5 cm × 2 mm was produced.

  The antibacterial activity value of test piece (I) was Escherichia coli = 1.5, Staphylococcus aureus = 1.1, and the antibacterial property was not sufficient. Moreover, yellowing of the molded object which evaluated test piece (I) by the light resistance test (Xenon arc Ci65 (ATLAS), irradiation illumination intensity: 0.35W2 / mat340nm, 1 week) was seen.

<Comparative Example 6>
Polyester resin (as monomer, ethylene oxide adduct of bisphenol A / terephthalic acid / fumaric acid polycondensation resin; number average molecular weight 4.5 × 10 ³ , weight average molecular weight 1.5 × 10 ⁴ , acid value = 15 mg / KOH, softening temperature: 100 ° C., Tg: 65 ° C. 80% by weight, as antibacterial particles, inorganic particles (volume average particle diameter D50 = volume average particle diameter D50 = supporting tricalcium phosphate hydrophobized with silicone oil) 20 wt% of 0.1 μm, silver content 1.3%) was put into a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) and mixed at 1000 rpm for 2 minutes. After that, using an extruder (TEM48BS, manufactured by Toshiba Machine Co., Ltd.), the kneaded material melted and kneaded at a screw rotation speed of 500 rpm and a cylinder temperature of 80 ° C. is cooled and then pulverized by a hammer mill to have an antibacterial composite having a volume average particle size of about 300 μm. Particles were obtained.

  Twin screw extrusion in which 90% by weight of NaCl-containing acrylonitrile-butadiene-styrene copolymer (NaCl addition concentration in ABS resin = 2%) and 10% by weight of the antibacterial composite particles were mixed well and the cylinder temperature was set at 260 ° C. An antibacterial agent-containing pellet was obtained by melt kneading at a rotation speed of 300 rpm using a machine (ZSK-25 manufactured by Toshiba Machine Co., Ltd.). The pellets were formed by an injection molding machine (model “M-50AII-DM” manufactured by Meiki Seisakusho Co., Ltd.) at a cylinder temperature of 240 ° C., a screw rotation speed of 80 rpm, an injection speed of 10 seconds, and a mold temperature of 250 ° C. A test piece (J) was obtained by injection molding to obtain a flat plate for antibacterial evaluation of 5 cm × 5 cm × 2 mm.

  The antibacterial activity value of the test piece (J) was E. coli = 0.6, Staphylococcus aureus = 1.1, and the antibacterial activity was not sufficient. Moreover, yellowing of the molded object which evaluated the test piece (J) by the light resistance test (Xenon arc Ci65 (ATLAS), irradiation illumination intensity: 0.35W2 / mat340nm, 1 week) was seen.

<Comparative Example 7>
Antibacterial composite particles prepared in the same manner as in Example 2 except that inorganic particles obtained by supporting silver metal on tricalcium phosphate as antibacterial inorganic particles A and zinc oxide inorganic particles as antibacterial inorganic particles B were used. In the same manner as in Example 2, an antibacterial raw yarn was obtained and subjected to an antibacterial test. As a result, the antibacterial activity value specifying S. aureus was 1.1, which was insufficient.

  It described in Table 2, 3 about the above-mentioned Examples 1-7 and Comparative Examples 1-7.

It can be used for applications requiring antibacterial properties. For example, antibacterial composite particles can be added and used on the surface of a synthetic resin, synthetic fiber, nonwoven fabric, synthetic paper, or the like.

Claims (11)

Antibacterial inorganic particles A having silver or silver ions and having a hydrophobicity of 20% or less;
Antibacterial composite particles comprising zinc, titanium, copper, or nickel, and antibacterial inorganic particles B having a degree of hydrophobicity of 30% or more.   2. The volume average particle diameter of the antibacterial inorganic particles A is 0.02 to 5 μm, and the volume average particle diameter of the antibacterial inorganic particles B is 0.01 to 3 μm. Antibacterial composite particles.   The antibacterial composite particle according to claim 1, wherein the antibacterial inorganic particle B is an oxide containing zinc, titanium, copper, or nickel.   2. The antibacterial composite particle according to claim 1, wherein the addition ratio of the antibacterial inorganic particle A and the antibacterial inorganic particle B is 1: 7 to 1: 0.25.   The antibacterial composite particles according to claim 1, wherein the antibacterial inorganic particles A are those in which silver or silver ions are supported on a phosphate compound.   2. The antibacterial composite particle according to claim 1, wherein a total amount of the antibacterial inorganic particle A and the antibacterial inorganic particle B is 0.1 wt% or more and 60 wt% or less.   The antibacterial composite particles according to claim 1, wherein the antibacterial inorganic particles A and the antibacterial inorganic particles B are surface-treated with a surface treatment agent containing at least one of Si, Al, and Ti.   The antibacterial composite particle according to any one of claims 1 to 7, wherein the antibacterial composite particle contains a resin, and the resin is a thermoplastic resin.   The antibacterial composite particles are obtained by melting and kneading at least the antibacterial inorganic particles A, the antibacterial inorganic particles B, and the resin, cooling and then pulverizing them so that the volume average particle diameter is 1 to 2000 µm. The antibacterial composite particle according to any one of claims 1 to 7.   The antibacterial fiber with which the antibacterial composite particle of any one of Claim 1 to 9 was mix | blended. An antibacterial resin molded article in which the antibacterial composite particles according to any one of claims 1 to 9 are blended.