KR20040057197A - Far Infrared Radiation Coating Composition Having Extinction Effect And Bio Precoated Metal Sheet Coated The Same - Google Patents

Abstract

PURPOSE: Provided is a paint composition having a quenching effect and a far infrared rays-emitting ability, which is excellent in a weather resistance and a heat resistance. A bio steel plate coated with the paint composition is also provided. CONSTITUTION: The paint composition contains 100pts.wt. of a silicone-modified resin and 10-60pts.wt. of a calcium carbonate powder having a particle size of 1-20 micron, wherein the silicone-modified resin comprises 10-40pts.wt. of a silicone resin and 60-90pts.wt. of a polyester resin. And the steel plate is coated with the paint composition, wherein the dry coating thickness of the paint composition is 5-20 micron.

Description

Far Infrared Radiation Coating Composition Having Extinction Effect And Bio Precoated Metal Sheet Coated The Same}

The present invention relates to a coating composition having a matting effect and far-infrared radiation and a bio-coated steel sheet coated with such a coating composition. More specifically, the present invention relates to a coating composition having a matting effect and far-infrared radiation containing silicone modified resin, and a bio-coated steel sheet coated with such a coating composition.

Far-infrared is a kind of electromagnetic wave that has a longer wavelength than visible light but has a very high frequency. It is a light energy in the range of 5-25 microns, which has a longer wavelength among infrared rays. Recently, as the efficacy of far infrared rays on the human body is known, far infrared radiation effects have been applied and utilized for various purposes ranging from far infrared saunas to home appliances, construction materials, and general household goods. Korean Patent Application No. 1997-18446 discloses the use of a raw material that emits far infrared rays by substituting Zn and Ag for zeolite, which is expensive and uneconomical.

The matting effect is an effect of reducing gloss, and has been usually achieved by adding silica to a coating composition. However, when a large amount of silica is added to the coating composition, the workability of the coating film is weak.

Accordingly, an object of the present invention is to provide a coating composition having a matting effect and far infrared radiation.

Another object of the present invention is to provide a coated steel sheet having a matting effect and far infrared radiation.

1 is a graph showing the change in glossiness of a 5 micron thick coating film with a change in the content of calcium carbonate,

2 is a graph showing the change in glossiness of the 15 micron thick coating film according to the change in the content of calcium carbonate,

3 is a graph showing the glossiness change of the 20 micron thick coating film with the change in the content of calcium carbonate.

According to one aspect of the invention,

Provided is a coating composition comprising 10 to 60 parts by weight of calcium carbonate powder based on 100 parts by weight of silicone modified resin and silicone modified resin.

According to another aspect of the present invention,

The coating composition of the present invention is provided with a coated steel sheet coated with a dry film thickness of 5 to 20 microns.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

When silica is used as a matting agent in the coating composition, there is a problem such as poor workability of the coated steel sheet. Therefore, in the present invention, a paint composition exhibiting synergy in the matting effect and far-infrared radiation by mixing silicone modified resin and calcium carbonate powder in a specific blending ratio without using a separate matting agent, and the coating composition is coated Painted steel sheet is provided.

In the present invention, silicone modified resin is used as the resin in the coating composition so as to exhibit a matting effect. Silicone-modified resins have siloxane bonds (-Si-O-Si-) in the resin, which not only provide excellent weatherability and heat resistance, but also quench.

Furthermore, the silicone modified resin can be used in combination with calcium carbonate in a specific formulation, thereby exhibiting far-infrared radiation effect superior to that when using calcium carbonate with a resin such as general polyester.

The silicone modified resin is a mixed resin of 10 to 40 parts by weight of the silicone resin and 60 to 90 parts by weight of the polyester resin. When applied to the coated steel sheet, the mixed resin of 20 parts by weight of silicone resin and 80 parts by weight of polyester is most preferred.

Silicone resin is a resin with excellent heat resistance and weather resistance. If the content of silicone resin increases, workability is problematic, so it is not suitable for coating steel sheet. If the silicone resin content is too small, heat resistance and weather resistance will not be improved. It is preferable to mix polyester resin in the said ratio.

Generally, a large amount of silicone resin is used when weatherability and heat resistance are required. However, when a large amount of silicone resin is contained, it is necessary to adjust the content of the silicone resin according to the use because workability is a problem.

In particular, calcium carbonate exhibits far-infrared radiation superior to that of other general resins and calcium carbonate in far-infrared radiation when mixed with silicone modified resin.

The calcium carbonate powder has far infrared radiation and may be mixed with the silicone-modified resin at 10 to 60 parts by weight based on 100 parts by weight of the resin. If the calcium carbonate powder is less than 10 parts by weight, far infrared radiation is weakened, meaning as a bio-steel sheet, and if it exceeds 60 parts by weight, far-infrared radiation is improved, but workability required by the coated steel sheet may be a problem. That is, when a large amount of calcium carbonate is added, chemical resistance falls, calcium carbonate powders aggregate together in resin, and dispersibility falls.

The calcium carbonate powder is preferably used having a particle size of 1 ~ 20 microns.

Powders having a particle size of less than 1 micron are difficult to manufacture and cause an increase in paint prices. If the particle size exceeds 20 microns, the particle size is too large when the coating film is formed using the paint composition, so that the surface roughness is not constant. The stability as a coating film will be lost.

In addition, other additives such as dispersants, leveling agents, curing accelerators, or waxes, which are generally added in the preparation of the resin composition for coating steel sheet coating in the coating composition, may be 1.0 parts by weight to 7.0 parts by weight based on 100 parts by weight of the resin. Can be added.

The coloring pigment is also generally used in the production of a resin composition for coating steel sheet coating and is used in an amount capable of imparting hiding power to the coating film, and is generally added in an amount of 10 to 80 parts by weight based on 100 parts by weight of the resin.

The type and content of other additives and coloring pigments are generally known in the art and do not particularly limit their type and amount.

When the paint composition is blended, a thinner mixed with ethylene glycol mono butyl ether, aromatic petroleum naphtha, diethylene glycol monobutyl ether, methanol, and the like may be used as necessary to control viscosity. The use of the solvent and its content are generally known in the art, and do not particularly limit the use, type and content of the solvent.

The paint composition of the present invention is typically pretreated and undercoated steel materials, more specifically, galvanized steel sheet coated with a coating thickness of 5 to 20 microns, preferably 15 microns, and dried at a drying temperature of 200-250 ℃ To form a coating film. If the thickness of the coating film is less than 5 microns, the coating film is too thin to have poor weather resistance, and if the coating film exceeds 20 microns, there is no further matting effect and far-infrared radiation improvement, but rather the workability of the coated steel sheet is lowered and the manufacturing cost is increased.

The coated steel sheet coated with the coating composition of the present invention is not only excellent in weatherability and heat resistance by silicon bonding of the silicone-modified resin, but also has quenching property of glossiness of 40 or less. In addition, due to the far-infrared radiation effect of calcium carbonate powder, it shows excellent far-infrared radiation activity, which requires the storage and ripening effect of food, the growth effect of plants, the maintenance of freshness of food by the activation of water molecules, and the blood circulation promotion. Where applicable.

The coating composition of the present invention exhibits a quenching effect due to siloxane bonds in the siloxane modified resin, and thus does not require the addition of silica that has been added separately to obtain the quenching effect.

Hereinafter, the present invention will be described in detail through examples.

Example

0.4 parts by weight of BYK-170, BYK-355, 0.3 parts by weight of BYK-355, 2 parts by weight of p-toluene sulfonic acid, and 4 parts by weight of wax, as a dispersant, in the amounts shown in the following Tables 1, 2 and 3 The paint composition was mixed using a thinner as a solvent and stirred at high speed at a speed of 1000 to 2000 rpm to prepare the coating compositions of Comparative Examples 1 to 10 and Inventive Examples 1 to 9. The silicone modified ester resin used in the invention is a mixed resin of 20 parts by weight of the silicone resin and 80 parts by weight of the polyester resin. Calcium carbonate powder was used having a particle size of 1-20 microns.

The coating compositions of Comparative Examples 1 to 3 and Inventive Examples 1 to 3 were coated on the galvanized steel sheets each of the coating compositions prepared above were subjected to chromate pretreatment of 20 × 10 cm and an epoxy resin at a dry film thickness of 4-5 microns. The coating compositions of Comparative Examples 4-7 and Inventive Examples 4-6 were made to have a dry coating thickness of 15 microns so as to have a dry coating thickness of 5 microns, and in comparison, 8-10 and Inventive Examples 7-9 were 20 microns Bar coating each to a thickness and dried for 24 seconds on a steel plate at 224 ℃ to form a coating layer.

Glossiness and far-infrared emissivity of each coated steel sheet on which the coating film was formed were measured and shown in Tables 1 to 3 and FIGS. 1 to 3.

Glossiness was evaluated by measuring the surface gloss using a 60 ° glossmeter (ASTM D523).

Far-infrared emissivity was measured at the wavelength range of 5 ~ 20㎛ by the Korea Institute of Building Materials and Research Institute (Far Infrared Ray Evaluation Evaluation Center) according to KS standard (KS L 2514, Section 6.4).

As can be seen from Tables 1 to 3, in the case of the comparative example in which the polyester resin is used as the resin, the increase in far-infrared emissivity due to the increase in the content of calcium carbonate is insufficient, whereas in the case of the invention example in which the silicone modified resin is used, calcium carbonate The increase of far-infrared emissivity was obtained by increasing the content of.

Furthermore, as can be seen in Tables 1 to 3 and FIGS. 1 to 3, the gloss reduction effect is better than that of the coating composition containing silicone modified resin and calcium carbonate.

The coating composition of the present invention and the coated steel sheet coated with the coating composition exhibit excellent weather resistance, heat resistance, and quenching effect due to the siloxane bond of the silicone modified resin, and the far-infrared emissivity due to the combination of the silicone modified resin and calcium carbonate is also excellent.

Claims (4)

A coating composition comprising 10 to 60 parts by weight of calcium carbonate powder based on 100 parts by weight of silicone modified resin and silicone modified resin. The coating composition according to claim 1, wherein the silicone modified resin is a mixed resin of 10-40 parts by weight of a silicone resin and 60-90 parts by weight of a polyester resin. The coating composition according to claim 1, wherein the calcium carbonate powder has a particle size of 1-20 microns. The coated steel sheet coated with the coating composition of any one of claims 1 to 3 with a dry coating thickness of 5 to 20 microns.