JP2005133190A - Antibacterial wire, and production method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide inexpensive antibacterial wire which has high antibacterial action, free from deterioration and discoloration, and is used for food equipment, medical equipment, various filters, interdental brushes or the like. <P>SOLUTION: The antibacterial wire has a plating layer on the surface of a metallic wire, wherein at least the surface layer in the plating layer is provided with an Ag-Zn alloy plating layer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a wire having an antibacterial action, in particular, an antibacterial wire coated with an antibacterial layer, and there is no deterioration or discoloration of the antibacterial action of the antibacterial coating layer even when exposed to chlorine. It is effective when used for various types of wires such as various filters and interdental brushes.

  One application of a wire having an antibacterial action is an interdental brush wire, an example of which is described in JP-A No. 11-33042. Interdental brushes are made by twisting brush bristles into a stainless steel wire. In order to prevent germs from growing on the surface of the stainless steel wire, it is required to use this as an antibacterial wire. The invention described in the above publication uses an antibacterial Ni—Cu alloy and an antibacterial stainless steel, and the antibacterial Ni—Cu alloy includes 66.5 wt% Ni and 31.5 wt% Cu. Further, there is an alloy containing 1.2% by weight of Fe, and antibacterial stainless steel includes stainless steel containing at least 1.5% by weight of Cu and 17% by weight of Cr.

A thin wire having an antibacterial action as in the prior art, that is, an antibacterial wire is generally a Cu-based alloy having an antibacterial action, but an Ag-plated wire having a high antibacterial action can also be used. is there. However, Ag has a much higher antibacterial effect than Cu, but Ag has a drawback that it is extremely expensive than Cu.
These conventional antibacterial wires are either alloys themselves or are Ag-plated, and Ag-plated ones are not only expensive, but when used for interdental brush wires, Since the Ag is combined with chlorine to form AgCl, the antibacterial action is reduced, and the surface is blackened and the appearance is deteriorated. May cause allergies to Ni ions eluted from the Ni-Cu alloy at the time of use, and there is a problem in biocompatibility. Further, an interdental brush made of stainless steel or the like has high adhesion to dental plaque and food, and cannot be said to have high cleaning properties. Furthermore, since the elution of Cu is controlled by forming a passive film on the surface of stainless steel, there is a problem that the effect of suppressing the growth of various bacteria decreases with time.
Japanese Patent Laid-Open No. 11-33042

  This invention uses a general-purpose inexpensive wire as a base material, and performs a relatively low cost surface treatment to add a rust-proofing action and an antibacterial action. An object of the present invention is to devise an antibacterial wire that does not deteriorate and does not deteriorate the appearance.

[Solution 1]
Means 1 taken to solve the above problem is a means for solving the structure of the antibacterial wire, and is based on the following (A) and (B).
(B) an antibacterial wire having a plated layer on the surface of the metal wire;
(B) An Ag—Zn alloy plating layer is provided on at least the surface layer of the plating layer.
[Action]
Since the metal wire is coated with an Ag—Zn alloy plating, it is rust-prevented with Zn and has an antibacterial action due to Ag.
Therefore, a wire having both antirust and antibacterial effects can be obtained.
Since the Ag—Zn alloy plating is extremely thin, the amount of Ag used per unit length of the wire is extremely small, and the cost of the Ag—Zn alloy plating is relatively low. Cost is relatively low.
In addition, Ag in the Ag—Zn alloy plating is relatively stable and does not combine with chlorine to form AgCl. Therefore, the antibacterial action is maintained for a long period of time and the color does not change.

[Embodiment 1]
In Embodiment 1 of Solution 1, the Ag content in the Ag—Zn alloy plating layer in the solution is 5 to 30% by weight.
When the Ag content in the alloy plating of Ag—Zn is less than 5% by weight, no particular antibacterial action is exhibited. On the other hand, even if it exceeds 30%, the antibacterial action does not become particularly high. Therefore, the Ag content of 5 to 30% by weight is the best range from the viewpoint of cost effectiveness.

[Embodiment 2]
In Embodiment 2 of Solution 1, the metal wire in the solution is carbon steel, stainless steel, pure titanium, or a titanium alloy.
When the metal wire is carbon steel, the base wire is inexpensive, when the metal wire is stainless steel, the antibacterial wire has high corrosion resistance, and when it is pure titanium or a titanium alloy, the weight is reduced.
The diameter of the wire is not particularly limited, but is practically in the range of 0.1 to 0.5 mm.

[Embodiment 3]
In Embodiment 3 of Solution 1, the thickness of the plating layer in the solution is 3 to 7 μm.
If the plating layer is less than 3 μm, the thickness of the Zn plating layer is insufficient, so that a special rust prevention effect cannot be obtained, and since the Ag content is very small, the antibacterial effect is also low. On the other hand, when the thickness is 7 μm or more, overcoating occurs, and the Ag content becomes excessive, resulting in an increase in cost.

[Embodiment 4]
In Embodiment 4 of Solution 1, the thickness of the Ag—Zn alloy plating layer among the plating layers is 2 to 5 μm.
If the thickness of the Ag-Zn alloy plating layer in which Ag is diffused is less than 2 μm, AgCl is generated and the antibacterial action is lowered, and the surface is blackened. If the thickness exceeds 5 μm, the Ag concentration on the surface is lowered. As a result, the antibacterial action decreases.
Therefore, in order for the Ag—Zn alloy layer to exhibit the maximum antibacterial action with a small amount of Ag, the thickness of the Ag—Zn alloy plating layer in which Ag diffuses in the Ag—Zn alloy plating layer is small. It is desirable that it is 2-5 micrometers.

[Solution 2]
Means 2 taken to solve the above problem is a means for solving the antibacterial wire manufacturing method according to the means 1, and is based on the following (a) to (c).
(A) applying a Zn plating to a metal wire;
(B) performing Ag plating on the Zn plating layer;
(C) After performing the above Ag plating, heating and thermal diffusion.
[Action]
It is relatively easy and low cost to apply Zn plating to a metal wire and further apply Ag plating thereon. Furthermore, it is relatively easy and low-cost to form a Ag—Zn alloy plating layer by thermally diffusing a wire formed with a Zn plating layer and an Ag plating layer through a heating furnace.
And since processing of these (a)-(c) is continuously performed, the antimicrobial wire of the solution means 1 can be manufactured comparatively cheaply.

As described above, since an antibacterial wire is formed by coating an inexpensive metal wire with a plated layer of an Ag—Zn alloy, this antibacterial wire has its antibacterial effect lowered by the chemical reaction of silver with chlorine. In addition, the surface is not blackened and the appearance is not deteriorated.
In addition, since a thin Ag—Zn alloy plating layer ensures a high antibacterial effect, it is possible to exert a high antibacterial effect with a very small amount of silver, and therefore, an antibacterial wire can be manufactured at a very low cost. .

Next, the best embodiment will be described.
In this embodiment, a stainless steel wire having a wire diameter of 5.5 mm is repeatedly heat-treated and drawn to 0.25 mm, and the surface of the 0.25 mm stainless steel wire 1 is electroplated to a thickness t. ₁ : Zn plating of 4 μm is applied. The plating speed in this case is not particularly a problem, but in this example, the Zn plating with the above thickness is completed in about 10 minutes. Ag plating with a thickness t _{2 of} 1 μm is applied on the Zn plating layer 2 by electroplating. The plating speed in this case is not particularly a problem, but in this example, the Ag plating layer 3 having the above thickness is formed in about 5 minutes (see FIG. 1).
The wire material that has been subjected to Ag plating is retained in a heating furnace at a heating temperature of 350 ° C. for 10 minutes to thermally diffuse Ag in the Zn plating layer. As a result, an Ag—Zn alloy plating layer (thermal diffusion layer) 4 having a thickness of 3 μm is formed (see FIG. 2). In this example, the Ag ratio in the Ag—Zn alloy plating layer is 15% by weight, the weight density of Ag in the Ag diffusion region is 10% on average, and the surface layer portion is approximately 20% at maximum. (See FIG. 2). Moreover, since the thickness of the zinc and silver plating layer (Ag—Zn alloy plating layer) is 3 μm, the wire diameter of the antibacterial wire covered with the Ag—Zn alloy plating layer is 0.26 mm. The thickness ratio of the Ag—Zn alloy plating layer is about 1.15%, which is extremely small.

[Other Examples]
In addition to this, while the thickness of the Ag—Zn alloy plating layer is 2 μm, the Ag ratio in the Ag—Zn alloy plating layer is 5 wt%, 10 wt%, 15 wt%, 20 wt% 25% by weight, 30% by weight, and 1% by weight and 3% by weight.

  An antibacterial action confirmation test was conducted on 8 cases including those of the above-mentioned Examples. That is, Escherichia coli and Staphylococcus aureus were each propagated in a petri dish, and the number of bacteria in the petri dish was measured. Then, 10 cut samples (length: 50 mm) of the above eight examples were put into the petri dish, and 25 ° C., humidity The cells were left under 70% for 24 hours, and the number of bacteria was counted for Escherichia coli and Staphylococcus aureus. The counted value is shown in FIG. When the Ag content is less than 5%, the antibacterial effect is drastically reduced. When the Ag content is 5% or more, it is apparent that the propagation of Escherichia coli and Staphylococcus aureus is almost zero.

These are sectional drawings of the wire just before alloying of an Example. These are sectional drawings of the antibacterial wire after alloying of an example. These are figures which show the result of the antimicrobial effect confirmation test of an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Metal wire material 2 ... Zn plating layer 3 ... Ag plating layer 4 ... Ag-Zn alloy plating layer

Claims (6)

  An antibacterial wire having a plating layer on the surface of a metal wire, wherein an Ag-Zn alloy plating layer is provided on at least a surface layer of the plating layer.   The antibacterial wire according to claim 1, wherein the Ag content in the Ag-Zn alloy plating layer is 5 to 30 wt%.   The antibacterial wire according to claim 1, wherein the metal wire is carbon steel, stainless steel, pure titanium, or a titanium alloy.   The antibacterial wire according to claim 1, wherein the plating layer has a thickness of 3 to 7 µm.   The antibacterial wire according to claim 1, wherein the Ag-Zn alloy plating layer has a thickness of 2 to 5 m among the plating layers.   A method for producing an antibacterial wire, comprising sequentially performing Zn plating and Ag plating on a metal wire, followed by heating and thermal diffusion.

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