JPH09217027A - Antimicrobial baking coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating material capable of being coated and baked on metal materials and useful for metal furnitures, building metal partitions, etc., by adding antimicrobial zeolite to a coating material containing a thermosetting resin varnish as a main component. SOLUTION: This antimicrobial baking coating material is obtained by adding (B) antimicrobial zeolite preferably in an amount of 0.5-5wt.% to (A) a coating material containing a thermosetting resin varnish (e.g. a polyester varnish, an amino resin varnish, a phenolic resin varnish) as a main component. The component B is obtained by adding an antimicrobial metal such as silver, zinc or copper to natural or synthetic zeolite by an ion exchange method. The addition of the silver ion is essential, and one or both of the copper ion and the zinc ion are added. The contents of the silver ion, the copper ion and the zinc ion are preferably 0.1-15wt.%, 0.1-8wt.% and 0.1-8wt.%, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial baking coating which can be suitably applied to a partition or the like of metal furniture or a building which requires antibacterial properties.

[0002]

2. Description of the Related Art Paint containing an antibacterial substance is well known as a so-called antifungal paint.

This product is generally made by mixing an organic or inorganic antibacterial substance (hereinafter simply referred to as an antibacterial agent) into an emulsion type paint such as vinyl acetate resin or acrylic resin. It should be noted that these antifungal paints are mainly used for surface coating of wood-based interior materials such as floors and walls of houses.

[0004]

According to the above-mentioned prior art, since the main component of the paint is a resin emulsion, baking coating on metal is impossible, and it is completely impossible to paint the surface of metal furniture or partitions. There was a problem that it could not be used. In addition, the conventional antibacterial agents are not always satisfactory in terms of antibacterial spectrum, safety for human body, heat resistance, durability of antibacterial activity and the like.

Therefore, in view of the problems of the prior art, an object of the present invention is to employ an antibacterial zeolite as an antibacterial agent, and mix it with a coating material containing a thermosetting resin varnish as a main component to obtain a metal material. Another object of the present invention is to provide an antibacterial baking coating that can be suitably used for baking coating on the same.

[0006]

The gist of the structure of the present invention for achieving the above object is to mix antibacterial zeolite into a coating material containing a thermosetting resin varnish as a main component.

The antibacterial zeolite can contain silver ions, and can further contain one or both of zinc ions and copper ions.

[0008]

According to the structure of the present invention, the thermosetting resin varnish becomes a synthetic enamel coating suitable for baking by mixing an appropriate amount of solvent and pigment. The thermosetting resin varnish referred to here is one or two types of thermosetting resin varnish such as polyester resin varnish, amino resin varnish, phenol resin varnish, alkyd resin varnish, melamine resin varnish, and epoxy resin varnish. The above-mentioned mixed varnish.

On the other hand, the antibacterial zeolite is a natural or synthetic zeolite containing an antibacterial metal such as silver, zinc or copper by ion exchange, and its general formula is XM _{2 / n 2} O 3.・ Al ₂ O ₃・ YSi O
It can be represented by ₂ · ZH ₂ O. Where M
Is an ion-exchangeable mono- or divalent metal ion, and n
= 1 and 2 are the valences of metal ions. Also, X,
Y and Z represent the numbers of metal oxide, silica and crystal water, respectively. Incidentally, there are various crystal forms of zeolite, but from the viewpoint of ion exchange capacity, sodalite,
A-type zeolite and X-type zeolite are excellent.

The antibacterial metal is intended to contain a part or all of the ion-exchangeable ions in the zeolite by ion exchange together with an appropriate amount of ammonium ions, and the content of the ammonium ions at this time is 0.5 to.
By setting the content to 5%, preferably 0.5 to 2%, discoloration of the zeolite can be prevented. On the other hand, from the viewpoint of antibacterial property, the content of silver ions in the zeolite is 0.1
The content of each of copper ion and zinc ion is preferably 0.1 to 8%. However, although silver ions are essential, one or both of copper ions and zinc ions may be appropriately added. Further, the content rate here is indicated by weight% with respect to the zeolite heated and dried at 110 ° C.

Since the antibacterial metal is an ion in zeolite and has an ionic bond in the skeletal structure of the zeolite, it exhibits a large antibacterial activity and is different from that due to physical bonding or adsorption. Antibacterial activity lasts semipermanently. Further, the antibacterial zeolite is excellent in heat resistance since the whole antibacterial agent is an inorganic material,
Intrinsically safe for the human body.

The amount of the antibacterial zeolite mixed in the paint is 0.5 to 5% by weight, particularly preferably 1 to 2%. This is because if the amount is too small, the antibacterial activity is insufficient, and if it is excessively mixed, the gloss and color tone of the coating film may be excessively changed.

[0013]

Example 1 Mixed varnish 50.0 comprising polyester resin varnish, melamine resin varnish and epoxy resin varnish
%, Color pigment 31.0%, solvent 18.6%, additive 0.
4% synthetic resin enamel coating, A type zeolite, 2% silver ion, 5% zinc ion, 4% ammonium ion 1% antibacterial zeolite, 2
% Were mixed to obtain sample paints 1 and 2. Zeolite has an average particle size of 2 μm and after ion exchange treatment, 110 ° C
It was dried by heating at the above heating temperature for 2 hours.

Sample paints 1 and 2 were diluted with thinner to adjust the viscosity, and spray-painted on a steel plate test piece (size 50 × 50 mm, thickness 0.8 mm) under the same conditions, and a baking temperature of 18
A plurality of test pieces 1 and 2 were obtained by performing a baking treatment at 5 ° C. for a baking time of 20 minutes. In addition, a comparative piece was manufactured using the same paint that did not contain antibacterial zeolite. Each coating film thickness (μm), gloss (G) of the test pieces 1 and 2 and the change in color tone of the test pieces 1 and 2 relative to the comparison piece (Δ)
E) was as summarized in FIG.

When the amount of the antibacterial zeolite mixed in is large, the gloss of the coating film tends to increase and the change in color tone tends to increase.

For the test pieces 1 and 2 and the comparative piece, the antibacterial activity test method for antibacterial processed products of the Society for Studying Inorganic Antibacterial Agents such as Silver
The antibacterial activity test was carried out according to the film adhesion method described in the 5th edition). The outline of the test method is as follows.

0.5 ml of the bacterial solution was instilled on the surface of each sample and incubated at 35 ° C. for 6, 10 and 24 hours. Then, the bacteria are washed out with a sterilized phosphate buffer, and the number of surviving bacteria in 1 ml of the washed-out test liquid is measured by the pour plate method using a standard agar medium (SA medium). However, the bacterial solution for inoculation is a 500-fold diluted medium of normal broth medium (NB medium), and the initial number of bacteria in the bacterial solution is shown in FIG.
It was as shown in.

The test results are summarized in FIG. In addition, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were used as test bacteria, and as a control, single culture of only the inoculum was also performed.

The antibacterial zeolite can exert a practically sufficient antibacterial activity even if the content is 1%.

[0020]

Example 2 Mixed varnish 56.0 comprising alkyd resin varnish, melamine resin varnish and epoxy resin varnish
%, Coloring pigment 26.5%, extender pigment 5.5%, solvent 1
Sample paints 1 and 2 were obtained by mixing 1% and 2% of the same antibacterial zeolite as in Example 1 with a synthetic resin enamel paint consisting of 0.0% and an additive of 2.0%.

Under the same conditions as in Example 1, test pieces 1 and 2 were obtained by spray coating and baking the sample paints 1 and 2 on steel plate test pieces. In addition, a comparative piece was manufactured using the same paint that did not contain antibacterial zeolite.

The coating film thickness (μm), gloss (G) of the test pieces 1 and 2 and the comparative piece, and the color tone change (ΔE) of the test pieces 1 and 2 relative to the comparative piece were as shown in FIG.

Even when 2% of antibacterial zeolite was mixed, there was no change in gloss and little change in color tone.

An antibacterial activity test was carried out on the test pieces 1 and 2 and the comparative piece according to Example 1, and the test results are summarized in FIG. However, the same figure shows the number of surviving bacteria for each test bacterial species when cultured for 24 hours after inoculation of the bacterial solution.

For Staphylococcus aureus and Escherichia coli, a content of 1% of antibacterial zeolite is sufficient, but for Pseudomonas aeruginosa, a content of 2% is preferable.

[0026]

As described above, according to the present invention, the antibacterial zeolite has a wide antibacterial spectrum and heat resistance by mixing the antibacterial zeolite in the coating material containing the thermosetting resin varnish as a main component. In addition to its excellent antibacterial activity, thermosetting resin varnish itself is suitable for baking, so it can be used in general metal furniture and interior materials as well as in hospital facilities and food factories. In addition, structural members such as metal partitions in facilities that require high hygiene,
It has an excellent effect that it can be suitably used for surface baking coating of panel materials and the like.

[Brief description of drawings]

FIG. 1 is a chart (1) showing the properties of a coating film.

Figure 2 Chart showing the results of antibacterial activity test (1)

FIG. 3 is a chart (2) showing the properties of the coating film.

[Fig. 4] Chart showing the results of antibacterial activity test (2)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiaki Yamamura 1-72, Komatsu City Industrial Park, Ishikawa Prefecture Komatsu Wall Industry Co., Ltd. (72) Inventor Biao Yoshinari 3-28-2 Negishi, Urawa City, Saitama Prefecture (72) Inventor Masashi Uchida 2-901 Makinohara, Higashi-ku, Nagoya-shi, Aichi 102 Kamioka Building 102 (72) Inventor Yasuo Kurihara 3-35 Toyooka-dori, Mizuho-ku, Nagoya-shi, Aichi

Claims (3)

[Claims] 1. An antibacterial baking coating obtained by mixing antibacterial zeolite into a coating containing a thermosetting resin varnish as a main component. 2. The antibacterial baking paint according to claim 1, wherein the antibacterial zeolite contains silver ions. 3. The antibacterial zeolite is zinc ion,
The antibacterial baking coating according to claim 2, which contains one or both of copper ions.