JPH09309757A - Antimicrobial artificial stone and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antimicrobial artificial stone harmless to human bodies, having sufficient antimicrobial activities and bringing no color change in a resin. SOLUTION: This amtimicrobial artificial stone comprises a base resin layer 2 and a gelcoat resin layer 1 in which an antimicrobial agent 4 of zirconium phosphate carrying silver is dispersed. The antimicrobial artificial stone is obtained by forming a film of the glecoat resin on the mold-surface of a casting mold, then casting the base resin, curing the resin and bring the gelcoat resin film to transfer and adhere to the base resin.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an antibacterial artificial stone and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, artificial stones such as artificial marble are generally often used for ceilings such as system kitchens and vanities, and bathroom counters. Since it is often used in the surroundings, it can be said that mold and E. coli are prone to grow. In particular, the tendency is remarkable in public facilities used by an unspecified number of people.

As a countermeasure against such mold and Escherichia coli, it is considered effective to form the surface portion of the artificial stone by using a resin containing an antibacterial agent.

Therefore, an antibacterial resin containing an organic antibacterial agent such as thiaventazole, which is relatively inexpensive and has a high antibacterial effect, or an inorganic antibacterial containing a metal having an antibacterial property such as silver. Antibacterial resins with agents added are manufactured.

[0005]

However, the above-mentioned organic antibacterial agents are known to have toxicity to the human body and corrosiveness to metals, and since the antibacterial agents undergo volatile decomposition, they have an antibacterial effect. There was also a question about the persistence of.

On the other hand, the inorganic antibacterial agent has good safety and stability, but its antibacterial effect is inferior to that of the above-mentioned organic antibacterial agent, and its price is high.

Further, since it is difficult to obtain an antibacterial effect unless the content is increased, if the addition amount is increased in order to obtain a desired antibacterial effect, the color is developed by silver when mixed with the resin.

Regarding the heat discoloration resistance, the antibacterial agent itself is stable, but the artificial stone is discolored by heating due to the effect of the cobalt salt contained in the curing accelerator of the resin. was there.

Therefore, in order to prevent discoloration, it has been proposed that the antibacterial agent itself is microencapsulated, but in this case, the antibacterial effect is diminished because the metal ions are less exposed.

Further, in the inorganic antibacterial agent containing a metal,
In most cases, metal particles such as silver are supported on an inorganic substance such as zeolite in order to improve dispersibility, but since these carriers themselves are colored, they are colored when mixed with a resin. .

An object of the present invention is to provide an antibacterial artificial stone which is harmless to the human body, has sufficient antibacterial properties, and does not cause discoloration of the resin.

[0012]

In order to solve the above problems, according to the present invention, an antibacterial artificial stone is used as a gel coat resin in which a base resin layer and an antibacterial agent having silver supported on zirconium phosphate are dispersed. Since the zirconium phosphate as a carrier and the compatibility with silver and resin are good, the dispersibility is improved, and the antibacterial effect is improved, and sterilization in a short time is performed. It is possible. Moreover, since zirconium phosphate is a light color, it hardly affects the color development of the resin.

Further, the gel coat resin layer has a content of the fatty acid or resin acid cobalt salt added as a curing accelerator of 0.003 parts by weight or less to prevent discoloration as much as possible.

Further, the content of the antibacterial agent in the gel coat resin layer is
0.1 to 2.0 parts by weight, the resin constituting the base resin layer and / or gel coat resin layer is a thermosetting resin, further, to the resin constituting the base resin layer and / or gel coat resin layer, It is also characterized by the addition of fillers and / or pigments.

As a method for producing such an antibacterial artificial stone, after the gel coat resin coating film is formed on the mold surface of the casting mold, the base resin is further cast and cured, The gel coat resin coating film is attached and transferred to the base resin.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The antibacterial artificial stone according to the present invention comprises two layers of a gel coat resin layer and a base resin layer.

Both resin layers are thermosetting resins, and at least the base resin layer is, for example, aluminum hydroxide,
It is preferable to add a filler made of powder such as glass frit, silica, and calcium carbonate to reduce the deformation rate and increase the strength, and further, a pigment can be appropriately added.

Further, in the gel coat resin layer, an antibacterial agent having silver supported on zirconium phosphate is dispersed.

Further, the gel coat resin layer is added with a curing accelerator having a content of fatty acid or cobalt salt of resin acid of 0.003 parts by weight or less, and by reducing the cobalt content while promoting the curing. Prevents artificial stone from discoloring when heated.

The content of antibacterial agent in the gel coat resin layer is
A good antibacterial effect can be obtained by adjusting the amount to 0.1 to 2.0 parts by weight.

In order to manufacture the antibacterial artificial stone having the above structure, the following manufacturing method is adopted.

That is, after the gel coat material is applied to the mold surface of the casting mold by a spray gun or the like to form a gel coat resin coating film, a resin material for forming the base resin layer is further cast. Then, the gel coat resin coating film is adhered and transferred to the same base resin to obtain an antibacterial artificial stone.

At this time, since the gel coat resin and the base resin are thermosetting resins, the curing can be promoted by applying heat, so that the production efficiency is improved.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an antibacterial artificial stone A according to the present invention. As shown in the drawing, it is formed of two layers, a thin film gel coat resin layer 1 and a base resin layer 2 having a predetermined thickness. Has been done.

The gel coat resin layer 1 is formed by dispersing an antibacterial agent 4 in an unsaturated polyester 3 having thermosetting property.

The antibacterial agent 4 is zirconium phosphate carrying silver oxide and has a strong antibacterial action against Escherichia coli and the like.

Further, as described above, since zirconium phosphate is used as the carrier, the compatibility with the resin is good and the dispersibility can be enhanced, and the compatibility with silver is also good. The carrier can be more surely supported and fixed as compared with the carrier.

Therefore, the antibacterial effect can be improved and sterilization can be performed in a short time. Moreover, since zirconium phosphate is a light color, it does not adversely affect the color development of the base resin layer 2.

The antibacterial agent 4 is added to the gel coat resin layer 1 in an amount of 0.1 to 2. In consideration of both the sterilization effect and the cost.
0 parts by weight are contained.

Further, the gel coat resin layer 1 contains a curing accelerator (not shown) containing a fatty acid or a resin acid cobalt salt.
Is added. In the present example, naphthenic acid and cobalt octanoate are used as the fatty acid cobalt salt.

Depending on the amount of the cobalt salt added, the oxidation number of cobalt is reduced from trivalent to divalent under the influence of silver ions when the gel coat resin is heated and cured.
Although the color of the gel coat resin changes from pale yellow to yellow-brown, in this example, the artificial stone during heating was promoted while reducing the content of the cobalt salt of naphthenate to 0.003 parts by weight or less to promote curing. Prevents yellowing.

On the other hand, like the gel coat resin layer 1, the base resin layer 2 is mixed with the unsaturated polyester 3 having thermosetting property, and the powder of aluminum hydroxide as the inorganic filler 5 is mixed to obtain the deformation ratio. We aim to increase strength while reducing
Further, a pigment (not shown) is appropriately mixed to form a desired color.

As the inorganic filler 5, besides aluminum hydroxide, glass frit, powder of silica, calcium carbonate or the like may be used.

As shown in FIG. 2, the antibacterial artificial stone A is suitably used for the top plate B1 of the wash basin B and other water around kitchens, bathrooms, etc., and it proliferates mold and E. coli due to its antibacterial action. It is possible to improve the hygiene aspect by suppressing the above, and since the product does not discolor as described above, it is possible to obtain a product with a desired color, and the decorative effect is also improved.

A method for producing such an antibacterial artificial stone A is shown in FIG.
Will be described with reference to.

(First Example) First, 100 parts by weight of a thermosetting unsaturated polyester was mixed with 1 part by weight of a silver zirconium phosphate antibacterial agent having silver supported on zirconium phosphate as a carrier and dispersed. Let

To this, 0.3 part by weight of a 6% cobalt naphthenate solution as a curing accelerator is added and mixed well.

Further, 2 parts by weight of a curing agent is added and mixed by stirring to obtain a gel coat material 10.

Gel coating material 10 having such a material mixing ratio
Is applied to the mold surface of the casting mold 6 with a spray gun 11 or the like and cured to form a thin gel coat resin coating film having a thickness of 0.3 to 0.5 mm (FIG. 3 (a)).

Next, 30 parts by weight of a thermosetting unsaturated polyester resin is mixed with 70 parts by weight of aluminum hydroxide as an inorganic filler 4, and 2 parts by weight of a hardening material are further mixed to obtain a base resin material 20. .

The base resin material 20 is cast on the gel coat resin layer 1 which has been cured and formed in the casting mold 6 as described above (FIG. 3 (b)), and is heated and cured. At this time, the gel coat resin coating film adheres and transfers to the base resin, the gel coat resin containing the antibacterial agent strongly adheres to the base resin, and there is no risk of peeling when commercialized, Quality is stable.

After a predetermined time has passed, the mold is removed (see FIG.
(c)) After further curing by heating, the antibacterial artificial stone A shown in FIG. 1 is obtained.

The antibacterial artificial stone A obtained by the above manufacturing method was tested for antibacterial performance. The results are shown in Table 1. In addition, Table 1
In the above, the control sample (blank) is a general artificial stone having no antibacterial property, and the sample as the comparative example is a gel coat material 10 containing 1 part by weight of a commercially available silver zeolite antibacterial agent.

[0045]

[Table 1]

The test method was as follows.

1. Test bacterium Escherichia Coli IF3
301 shares) 2. Preparation of Bacterial Solution The test bacteria were inoculated into a soybean casein digest medium (Nippon Pharmaceutical Co., Ltd.) and cultured at 30 ° C. with shaking overnight.

After centrifugation and washing of the test bacterial solution, 1/1000 concentration broth medium (Eiken Kagaku, but 1/100 for Staphylococcus aureus)
It was diluted 10,000 times with (concentration) to obtain a bacterial solution. The viable cell count of this bacterial solution was measured to determine the bacterial concentration of the test solution.

3. Test operation 80% in advance
A sample (blank (control), Example 1 and Comparative Example) sterilized with ethanol was added with 0.15 ml of the bacterial solution (0.4 ml under the condition of contact for 24 hours).
) Was dropped, and a sterilized glass plate was placed on the sample to bring it into close contact with the sample.

Under a wet condition (the chamber was moistened with 1.8 M NaCl to prevent drying), they were contacted with each other for 1 to 24 hours under light shielding, and then wiped off with a sterile gauze to collect a reaction bacterial solution.

4. Measurement of viable cell count 1 ml of collected bacterial solution
Was diluted with ordinary agar medium (Nissui Pharmaceutical).

0.1 ml of the recovered bacterial solution diluted with sterile 0.8% saline (= physiological saline) was applied to a regular agar medium.

After culturing at 36 ° C. for 1 day, the number of bacteria was measured and the sterilization rate was calculated.

As is clear from the above test results, the antibacterial artificial stone A according to the present invention exhibits strong antibacterial performance in a short time.

(Second Example) The difference between this example and the previous example is that, as a curing accelerator, 0.3% by weight of 6% cobalt naphthenate solution was used in the previous example. Then, it was decided to use a solution in which the cobalt offthenate solution was 0.04 part by weight and the content of the cobalt offtenate cobalt salt in the gel coat material 10 was 0.003 parts by weight or less.

That is, when a fatty acid cobalt salt such as cobalt naphthenate or cobalt octanoate is used, the gel coat material 10 may be discolored when the gel coat material 10 is heat-cured. The discoloration effect is prevented by adjusting the amount of cobalt offthenic acid salt to be 0.003 parts by weight or less.

Here, the degree of discoloration of the antibacterial artificial stone A according to this example, the antibacterial artificial stone A according to the first example, and a general artificial stone having no antibacterial property as a control (blank) was tested. The results are shown in Table 2.

[0058]

[Table 2]

As a test method, each sample piece was immersed in boiling water for 2 hours, and the discoloration after cooling was confirmed using a color difference meter.

As can be seen from the test results, since the antibacterial artificial stone A according to this example contained 0.003 parts by weight or less of the cobalt offenoate cobalt salt contained in the curing accelerator,
Despite containing the inorganic antibacterial agent 4 containing silver,
It was possible to stop the discoloration to the same level as general artificial stones without antibacterial properties.

[0061]

The present invention is embodied in the form described above and has the following effects.

The antibacterial artificial stone is composed of a base resin layer and a gel coat resin layer in which an antibacterial agent having silver supported on zirconium phosphate is dispersed, whereby the antibacterial agent is well dispersed and further stable. Since it can be carried, sterilization can be performed in a short time, and the antibacterial effect can be significantly improved.

Since zirconium phosphate is a light color,
There is no danger of affecting the color development of the product.

Since the gel coat resin layer is added with a curing accelerator having a content of fatty acid or cobalt salt of resin acid of 0.003 parts by weight or less, discoloration of the gel coat resin layer can be surely prevented.

The content of the antibacterial agent in the gel coat resin layer is
By using 0.1 to 2.0 parts by weight, it is possible to manufacture at low cost while exhibiting sufficient antibacterial performance.

By using a thermosetting resin as the resin forming the base resin layer and / or the gel coat resin layer,
Curing can be accelerated by heating, and manufacturing efficiency can be improved.

By adding a filler and / or a pigment to the resin constituting the base resin layer and / or the gel coat resin layer, the deformation rate of the product can be reduced and the quality can be improved. When added, it can be colored in a desired color.

After the gel coat resin coating film is formed on the mold surface of the casting mold, the base resin is further cast and cured to transfer the gel coat resin coating to the base resin. As a result, the gel coat resin containing the antibacterial agent strongly adheres to the base resin, and there is no fear of peeling when it is commercialized, and the quality is stable.

[Brief description of drawings]

FIG. 1 is an explanatory view of an antibacterial artificial stone according to the present invention in a sectional view.

FIG. 2 is an explanatory view of a wash basin to which the antibacterial artificial stone is applied.

FIG. 3 is an explanatory view showing a method for producing the antibacterial artificial stone.

[Explanation of symbols]

 A Antibacterial artificial stone B Washbasin B1 Top plate 1 Gel coat resin layer 2 Base resin layer 3 Unsaturated polyester 4 Antibacterial agent 5 Inorganic filler 6 Casting mold 10 Gel coating material 20 Base resin material

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C08L 101/00 C08L 101/00 C09D 5/14 PQM C09D 5/14 PQM E04F 13/18 8913-2E E04F 13/18 A // (C04B 26/18 14:34 24:04) (A01N 59/26 59:16) B29K 67:00 103: 06 C04B 111: 54

Claims (6)

[Claims] 1. An antibacterial artificial stone comprising a base resin layer and a gel coat resin layer in which an antibacterial agent having silver supported on zirconium phosphate is dispersed. 2. The gel coat resin layer is added with a curing accelerator having a content of fatty acid or cobalt salt of resin acid of 0.003 parts by weight or less.
Antibacterial artificial stone described. 3. The antibacterial agent content of the gel coat resin layer
The antibacterial artificial stone according to claim 1 or 2, wherein the content is 0.1 to 2.0 parts by weight. 4. The antibacterial artificial stone according to claim 1, wherein the resin constituting the base resin layer and / or the gel coat resin layer is a thermosetting resin. 5. The antibacterial artificial structure according to claim 1, wherein a filler and / or a pigment is added to the resin forming the base resin layer and / or the gel coat resin layer. stone. 6. The gel coat resin coating film is adhered to and transferred to the base resin by forming the gel coat resin coating film on the mold surface of a casting mold and then casting and curing the base resin. The method for producing an antibacterial artificial stone according to any one of claims 1 to 5, characterized by being obtained.