JPH0797480A - Antibacterial molding resin chip with improved whiteness, its production, and production of antibacterial synthetic fiber - Google Patents

Abstract

PURPOSE:To obtain the resin chip excellent in whiteness and antibacterial properties by dispersing specified amts. of a specific inorg. substance and an alkali halide in a molding resin. CONSTITUTION:0.1-80wt.% (based on the resin) antibacterial inorg. substance having ion-exchange sites exchanged partially or completely with Ag ions (e.g. an Ag ion-contained antibacterial zeolite which is obtd. by treating mordenite with an aq. soln. of silver nitrate) and 0.0001-1wt.% (based on the resin) alkali halide (e.g. KI) are dispersed in a molding resin (e.g. nylon 6). The inorg. antibacterial inorg. substance and the alkali halide are added to the resin pref. before the completion of polymn. for producing the resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial resin chip for molding, a method of manufacturing the same, and an improvement of a method of manufacturing an antibacterial synthetic fiber comprising the same. For more details,
The present invention relates to improving the whiteness of antibacterial resin chips for molding and antibacterial synthetic fibers.

[0002]

2. Description of the Related Art Compared to an antibacterial resin molded product obtained by adhering an antibacterial organic compound such as an aromatic halogen compound or a quaternary ammonium salt after molding into a fiber or a film, the antibacterial performance is less deteriorated under use conditions. In terms of obtaining durable antibacterial performance, an antibacterial resin molded product is produced from a resin composition in which an antibacterial inorganic substance substituted with a metal ion having an antibacterial property such as silver, copper or zinc is blended inside. The method is known.

Among them, a resin composition containing an antibacterial zeolite substituted with silver ions has extremely high antibacterial performance durability and safety, and is therefore used as a raw material for familiar resin moldings such as fibers, films and various containers. It has been widely used (Japanese Patent Laid-Open No. 59-133235, etc.).

However, when the antibacterial zeolite is blended with a resin, the resin is colored, and various methods for preventing the coloring have been proposed.

For example, a discoloration inhibitor (benzotriazole compound, oxalic acid anilide compound, cyanoacrylate compound, benzophenone compound, hindered amine compound) for the purpose of reducing discoloration of a composition containing antibacterial zeolite in a resin over time. , Hindered phenol compounds, phosphorus compounds, sulfur compounds, hydrazine compounds, etc.) have been proposed (Japanese Patent Laid-Open No. 63-265958).

It has also been proposed to produce an antibacterial resin composition using an antibacterial inorganic material obtained by halogenating a part of silver ions for the purpose of eliminating coloring of the resin itself containing the antibacterial inorganic material. (JP-A-3-200702).

Furthermore, a method has been proposed in which an alkali halide is added to an antibacterial polymer before spinning for the purpose of improving the whiteness of a fiber containing an antibacterial zeolite (Japanese Patent Application Laid-Open No. 4-228609).

[0008]

Problems to be Solved by the Invention JP-A-63-2659
Although the discoloration preventing agent described in JP 58 can suppress the discoloration of the antibacterial resin composition over time, it cannot suppress the coloring of the antibacterial resin composition due to the color of the antibacterial zeolite itself, In particular, when the amount of the antibacterial zeolite added was increased, the resin composition was colored brown or black to a large extent, and it was difficult to obtain a white or light colored molded product.

Further, in a method of reducing the coloring of an antibacterial resin composition by using an antibacterial inorganic material obtained by halogenating a part of silver ions, a small amount of silver halide has a sufficient effect of improving coloring. On the contrary, if the amount of silver halide is large, the antibacterial performance is greatly deteriorated.Therefore, there is a big problem that the antibacterial performance must be sacrificed in order to sufficiently reduce coloration. It was not preferable.

Furthermore, according to the method of blending an alkali halide with an antibacterial polymer at the time of molding, a certain degree of whiteness improving effect can be obtained, but it is not sufficient. Particularly, in order to obtain a white or pale antibacterial fiber. Further improvement in whiteness has been demanded.

Therefore, the present invention can solve the above-mentioned drawbacks which cannot be solved by the prior art, and can sufficiently improve the whiteness, and moreover, it is as excellent as the conventional antibacterial resin molded product. The main purpose is to provide an antibacterial resin chip for molding which can exhibit antibacterial properties, and further to obtain an antibacterial synthetic fiber excellent in both whiteness and antibacterial property.

[0012]

In order to achieve this object, the molding antibacterial resin chip of the present invention with improved whiteness has a part or all of the ion-exchange site in the molding resin which is at least silver. The ion-substituted antibacterial inorganic substance and the alkali halide are 0.1 to 80 relative to the resin, respectively.
%, And 0.0001 to 1% by weight dispersedly contained.

Further, the antibacterial resin chip for molding is prepared by adding an antibacterial inorganic material in which a part or all of the ion exchange sites are replaced with at least silver ions and an alkali halide at a stage before completion of polymerization. Manufactured.

Furthermore, the antibacterial synthetic fiber having improved whiteness is obtained by adjusting the concentration of the antibacterial inorganic substance by mixing the above-mentioned molding antibacterial resin chip and the above-mentioned molding resin chip containing no antibacterial inorganic substance. Manufactured by melt spinning.

That is, if an antibacterial resin chip for molding is produced by adding an alkali halide in the polymerization system together with the antibacterial inorganic substance before the completion of the polymerization, the antibacterial performance is not deteriorated and its whiteness is reduced. The degree can be improved sufficiently.

Further, the antibacterial synthetic resin chip is mixed with a molding resin chip containing no antibacterial inorganic substance to adjust the concentration of the antibacterial inorganic substance and then melt-spun to further increase the whiteness of the antibacterial synthetic fiber. It can be improved.

The inorganic material used as a raw material for the antibacterial inorganic material in the present invention is not particularly limited as long as it is an inorganic material capable of carrying silver ions by ion exchange. For example, silica / alumina-based zeolites; metal oxides such as titanic acid, activated alumina, antimonic acid; phosphates such as calcium phosphate, zirconium phosphate, hydroxyapatite; and composite inorganic substances obtained by coating amorphous silica gel with aluminosilicate. Can be mentioned.

Particularly, zeolite is preferably used because it is extremely safe. As the zeolite, either natural zeolite or synthetic zeolite can be used. A typical example is Chabasite (Chba
zite), Crynovoptilolite (Clinopti)
lolite), Eriolite,
Natural zeolites such as Faujasite and Mordenite; A
Type, X type, Y type, mordenite type, pentasil type, ferrienite type, beta type, ZSM-5 type, ZSM-11
Suitable types are synthetic zeolites such as types. The silica / alumina molar ratio is not particularly limited, but a high molar ratio of 15 or more is preferable in order to suppress coloration during resin blending and enhance the dispersibility of the zeolite particles.

The antibacterial inorganic substance referred to in the present invention is obtained by substituting a part or all of the ion-exchangeable sites of the inorganic substance with silver ions.

It is also possible to use a composite type antibacterial inorganic substance in which other metal ions such as copper and zinc are simultaneously substituted with silver ions. It is preferable that 5% or more by weight is silver ions.

The resin usable in the present invention is not particularly limited as long as it can be molded, and examples thereof include polyamide, polyester, polyolefin, polyvinyl alcohol, acrylic resin, urethane resin and the like. In particular, polyamide and polyester obtained by condensation polymerization are suitable as the resin for obtaining the antibacterial synthetic fiber. Among them, a polyamide having a reaction form in which water is allowed to coexist in the initial stage of the polymerization reaction is more preferably used because it is easy to uniformly mix the alkali halide during the polymerization.

The amount of silver-substituted antibacterial inorganic material mixed in the resin chip depends on the amount of silver substituted, the type of resin,
The optimum amount may be selected depending on the usage of the chip and the intended use of the molded product. For example, when adjusting the concentration by mixing with a resin chip containing no antibacterial inorganic substance,
The blending amount may be slightly higher, 0.1 to 80% by weight.
Among them, 0.5 to 40% by weight is preferable, and particularly 1 to 20
Weight percent is preferred. If the blending amount is too large, molding becomes difficult, which is not practical.

The compounding of the antibacterial inorganic substance is a substantial polymerization process of the resin, such as during the compounding of the raw materials before the polymerization of the resin or during the polymerization, in order to uniformly disperse the antibacterial inorganic substance in the resin. The resin is polymerized before the completion of the polymerization.

As the alkali halide used in the present invention, for example, lithium chloride, potassium chloride, sodium chloride, lithium iodide, potassium iodide, sodium iodide, lithium bromide, sodium bromide, potassium bromide and the like are preferable. And potassium halide is particularly preferable.

The amount of the alkali halide to be mixed with the resin can be changed depending on the amount of the antibacterial inorganic substance and the kind of the resin, but generally 0.0001 to 1% by weight is suitable. Above all, 0.0005 to 0.5% by weight
Is preferable, and 0.001 to 0.1% by weight is particularly preferable. If the blending amount is too small, the whiteness improving effect is insufficient. On the contrary, if the amount is too large, the antibacterial inorganic substance is aggregated and the uniform dispersion thereof is hindered, which is not preferable.

The blending of the alkali halide is substantially the same as the blending of the silver-substituted antibacterial inorganic substance, such as during the blending of the raw materials before the polymerization of the resin or during the polymerization, and is substantially a step of polymerizing the resin and It is carried out at a stage before the completion of polymerization.

Coloring proceeds by contact between a highly active low molecular weight substance and a silver-substituted antibacterial inorganic substance during polymerization, and therefore, the highest anticoloring effect can be obtained by coexisting an alkali halide from this polymerization step. The obtained whiteness can be further improved.

On the other hand, in the method in which the antibacterial inorganic substance is previously treated with an alkali halide and then added to the resin polymerization step, the progress of coloration during polymerization is small and the desired effect cannot be obtained. Further, even when the alkali halide is added at a stage after the polymerization of the resin is completed, it is difficult to sufficiently reduce the coloring of the resin which has already progressed during the polymerization.

The antibacterial resin chip for molding of the present invention may be molded into various forms such as fibers, films, plates, containers and granules by a conventional method to produce an antibacterial molded product. that time,
An antibacterial inorganic substance in a molding antibacterial resin chip is contained in a high concentration, and before the molding, a high concentration antibacterial chip and
It is preferable to adjust the concentration of the antibacterial inorganic substance by mixing with another resin chip that does not contain the antibacterial inorganic substance, in order to further improve the whiteness of the obtained antibacterial molded article.

The obtained antibacterial molded article can be used for various purposes, but it is particularly effective for obtaining white or light-colored antibacterial synthetic fibers.

If necessary, a matting agent, a heat-resistant agent,
Ordinary additives such as a light resistance agent, a dispersant, and an antistatic agent may be contained in the chip at the same time, or may be added at the time of molding.

[0032]

The present invention will be described in more detail with reference to the following examples.

[Examples and Comparative Examples] Mordenite-type zeolite (silica / alumina molar ratio 16) was treated with an aqueous silver nitrate solution to obtain an antibacterial zeolite containing 9.5% by weight of silver ions.

Next, to the 85% by weight aqueous solution of ε-caprolactam, the following amounts (blending amount with respect to the solid content) of the antibacterial inorganic substance and the alkali halide were added.

No. 1: 5% by weight of antibacterial zeolite and 0.0005% by weight of potassium iodide.

No. 2: 10% by weight of antibacterial zeolite,
0.002% by weight of potassium iodide.

No. 3: 10% by weight of antibacterial zeolite,
0.005% by weight of potassium bromide.

No. 4: 20% by weight of antibacterial zeolite,
0.015% by weight of potassium iodide.

For comparison, only 5% by weight of antibacterial zeolite was blended and adjusted (No. 5).

The aqueous solutions of ε-caprolactam of Nos. 1 to 5 were pressure-polymerized in the usual manner into chips to obtain antibacterial nylon 6 chips containing a high concentration of antibacterial zeolite. The 98% sulfuric acid relative viscosity (ηr) of the obtained high-concentration antibacterial chip was as shown in Table 1.

Next, each high-concentration antibacterial chip and a normal nylon 6 chip containing no antibacterial zeolite etc.
The mixture was thoroughly mixed in the proportions shown in Table 1, dried, and then melt-spun and stretched by an ordinary method, and 40 denier and 10 filaments of antibacterial nylon 6 filament yarn were wound into a bun shape.

Further, as a comparison, nylon 6 filament yarn was produced in the same manner as above from only ordinary nylon 6 chips containing no antibacterial zeolite and wound into a parn shape (No. 6).

The surface whiteness of the obtained pearl was measured by a color meter (COLOR MESURI manufactured by Nippon Denshoku Industries Co., Ltd.).
NG SYSTEM).

Further, these filament yarns were made into a tubular knitted fabric by a conventional method, and antibacterial properties were evaluated by the following shake flask method.

Evaluation of antibacterial property: A suspension buffer of a test bacterium (Staphylococcus aureus) was added to a sample cloth, and 1 was put in a closed container.
Shake 50 times / min for 1 hour, count the number of viable cells after the shaking, and obtain the difference (%) in reduction rate with respect to the number of cells of the suspension added.

[0046]

[Table 1] As shown in Table 1, in the case of the antibacterial chip for molding of the present invention in which an alkali halide is blended before the completion of polymerization (No.
Nos. 1, 2, 3, 4) were able to obtain filament yarns having excellent whiteness and antibacterial properties.

On the other hand, when the antibacterial chip containing no alkali halide was used (No. 5), the antibacterial property was excellent but the whiteness was inferior.

When the antibacterial nylon 6 masterbatch was not added (No. 6), the antibacterial property could not be obtained.

COMPARATIVE EXAMPLE An antibacterial zeolite containing a high concentration of antibacterial zeolite was prepared in the same manner as in No. 5 of Example 1 except that 0.05% by weight of alkali halide was added to the resin when the chips were mixed. Chips were mixed and melt-spun.

The obtained antibacterial fiber has a good antibacterial property, as shown in Table 1 as No. 7, and although the yarn whiteness was slightly improved, a sufficiently good whiteness was not obtained. It was

[0051]

According to the present invention, the following effects can be obtained.

The whiteness of an antibacterial resin molded product obtained by blending an antibacterial inorganic substance substituted with silver ions can be greatly improved. Moreover, since the antibacterial performance is not reduced, various antibacterial resin molded products having excellent antibacterial properties and whiteness can be obtained.

Therefore, it is particularly useful as an antibacterial fiber for which color tone is important, and is suitable for clothing such as lingerie and underwear, socks such as stockings and socks, and upholstery. . It is also useful for various applications such as antibacterial films, plates, containers, and granular materials.

Claims (3)

[Claims] 1. An antibacterial inorganic substance in which a part or all of the ion exchange sites are substituted with at least silver ions and an alkali halide in the molding resin are 0.1 to 80% by weight and 0.1% to the resin, respectively. An antibacterial resin chip for molding with improved whiteness, which is characterized by being dispersedly contained in an amount of 0001 to 1% by weight. 2. The antibacterial resin chip according to claim 1, wherein an antibacterial inorganic material in which a part or all of the ion exchange sites are replaced with at least silver ions and an alkali halide are added before the completion of the polymerization. A method for producing an antibacterial resin chip for molding with improved whiteness, the method comprising: 3. An antibacterial synthesis by melt spinning after adjusting the concentration of the antibacterial inorganic substance by mixing the antibacterial resin chip for molding according to claim 1 and the resin chip for molding not containing the antibacterial inorganic substance. A method for producing an antibacterial synthetic fiber with improved whiteness, which comprises producing a fiber.