KR100892414B1 - Colored-steelsheet and paint compositions coated thereon for sparkling formations - Google Patents

Abstract

A chromium coating layer is formed on a substrate layer (steel plate) by a coating type chromate treatment as a pretreatment for preventing corrosion and improvement in paint adhesion, and a base coating layer and a clear coating layer are formed so as to form a sparkling appearance on the chromium coating layer. A color coated steel plate formed sequentially with paint layers to form a sparkling appearance; The base paint for forming the base coating layer comprises 40 to 50 parts by weight of a polyester resin as a main resin, 5 to 15 parts by weight of a melamine resin for curing the inside and the outside of the coated film, 1 to 3 parts by weight of a silicone resin for facilitating coloring, 0.1 to 10 parts by weight of an organic or inorganic pigment for color composition, 5 to 25 parts by weight of a solvent such as an aromatic hydrocarbon or the like and an additive such as a defoaming agent and a curing accelerator and wax 4 to 8 parts by weight; The clear paint for forming the clear paint layer comprises 20 to 25 parts by weight of a polyester resin, 25 to 30 parts by weight of an isocyanate for a urethane curing system, 0.5 to 1 part by weight of a melamine resin for improving coat hardening, 0.1 to 5 parts by weight of a pearl or metallic paste pigment for clear color composition, 20 to 30 parts by weight of a solvent such as aromatic hydrocarbon or the like, and 4 to 5 parts by weight of an additive such as defoamer, curing accelerator and wax, By creating a sparkling appearance that is orderly and orderly, it exhibits a unique texture.

Description

[0001] The present invention relates to a sparkling-forming coating material and a color coated steel sheet coated with the coating material,

The present invention relates to a sparkling coating material and a color coated steel sheet coated with the coating material. More particularly, the present invention relates to a sparkling coating material for forming a natural and orderly sparkling appearance by completely exposing a base coating film, And a color coated steel sheet coated with the coating.

Conventional color coated steel sheets are coated with a coating type chromate as a pretreatment for preventing corrosion and adhesion of paints on a base steel sheet in order to form an appearance on a coated steel sheet, and then a PCM (Pre-Coated Metal) In the formation of the first and second polymeric polyester films, amide type wax was used to form a horn-toned color steel sheet, and the form of the formed coating film formed was only partially exposed by the clear coating film of the base coating film to form a simple outline .

The present invention provides a sparkling-forming coating material and a color-coated steel sheet coated with the coating material, wherein the base coating film is completely exposed when the clear coating film is formed to completely expose the base coating film, and the connection and short-circuiting of the clear coating film are clearly formed, thereby forming a natural and orderly sparkling appearance It has its purpose.

The sparkling appearance is formed by the principle that the clear coating film which is dried due to the role of the dissolving chemical reaction between the polyester resin and the amine and the amide wax during isocyanate urethane curing coexists to expose the base coating film as it is. The base coating film is exposed in the form of a clear coating film does not continue to exist independently.

The coating material for sparkling according to the present invention is a coating material for forming a chromium coating layer on a substrate layer (steel plate) by performing a coating type chromate treatment as a pretreatment for preventing corrosion and improving paint adhesion, And a clear paint layer are sequentially formed to form a sparkling appearance, wherein the base paint for forming the base paint layer comprises 40 to 50 parts by weight of a polyester resin as a main resin, , 1 to 3 parts by weight of a silicone resin for facilitating the formation of a sparkling appearance by controlling the surface tension of the coating film surface, 0.1 to 10 parts by weight of an organic and inorganic pigment for color composition, 5 to 25 parts by weight of a solvent such as a hydrocarbon, and 4 to 8 parts by weight of an additive such as a defoaming agent, a curing accelerator, and a wax.

The clear paint for forming the clear paint layer comprises 20 to 25 parts by weight of a polyester resin, 25 to 30 parts by weight of an isocyanate for a urethane curing system, 0.5 to 1 part by weight of a melamine resin for improving coat hardening, 0.1 to 5 parts by weight of a pearl or metallic paste pigment for clear color composition, 20 to 30 parts by weight of a solvent such as aromatic hydrocarbon or the like, and 4 to 5 parts by weight of an additive such as defoaming agent, curing accelerator and wax .

It is preferable that 0.5 to 1 part by weight of an amide wax is added to the urethane curing system of the polyester resin and the isocyanate resin.

The polyester resin of the clear paint has a number average molecular weight of 5,000 to 6500 and an OH value of 40 to 60, and the isocyanate resin is preferably a resin based on TDI (toluene diisocyanate).

A color coated steel sheet coated with a sparkling coating material according to the present invention is characterized in that a chromium coating layer is formed on a substrate layer (steel sheet) by performing a coating type chromate treatment as a pretreatment for preventing corrosion and improving adhesion of a paint, A color coated steel sheet in which a base coating layer and a clear coating layer are sequentially formed so as to form a sparkling appearance on a coating layer, wherein the base coating forming the base coating layer comprises 40 to 50 parts by weight of a polyester resin as a main resin, 5 to 15 parts by weight of a melamine resin for curing the inside and outside of the coated film, 1 to 3 parts by weight of a silicone resin for facilitating the formation of sparkling appearance by controlling the surface tension of the coating film surface, 0.1 to 10 parts by weight of organic and inorganic pigments And 5 to 25 parts by weight of a solvent such as an aromatic hydrocarbon or the like, and 4 to 8 parts by weight of an additive such as a defoaming agent, a curing accelerator and a wax,

The clear paint for forming the clear paint layer comprises 20 to 25 parts by weight of a polyester resin, 25 to 30 parts by weight of an isocyanate for a urethane curing system, 0.5 to 1 part by weight of a melamine resin for improving coat hardening, 0.1 to 5 parts by weight of a pearl or metallic paste pigment for clear color composition, 20 to 30 parts by weight of a solvent such as aromatic hydrocarbon or the like, and 4 to 5 parts by weight of an additive such as defoaming agent, curing accelerator and wax .

The thickness of the clear paint layer formed by the clear paint is preferably 10 to 15 占 퐉.

According to the sparkling coating material of the present invention and the color coated steel sheet coated with the coating material, the base coating film is completely exposed, and the connection and short-circuiting of the clear coating film are apparently observed (short- By forming a regular sparkling appearance, it is possible to produce a color coated steel sheet having a unique texture.

Hereinafter, the present invention will be described more specifically with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a structural view showing an example of a color coated steel sheet produced by applying the sparkling-forming coating material of the present invention. Fig. As shown in the figure, a chromium coating layer 20 is formed on the substrate layer 10 (steel plate) by a coating type chromate treatment as a pretreatment for preventing corrosion and improving the adhesion of the paint, and on the chromium coating layer 20 A base coating layer 30 and a clear coating layer 40 which form a sparkling appearance are formed. A primer coating layer may be formed between the chromium coating layer 20 and the base coating layer 30 to improve workability and adhesion to the base coating layer for forming sparkling.

The base coating material for forming the base coating layer 30 includes 40 to 50 parts by weight of a polyester resin as a main resin, 5 to 15 parts by weight of a melamine resin for curing the inside and the outside of the coating film, 1 to 3 parts by weight of a silicone resin for facilitating the formation of a sparkling appearance, 0.1 to 10 parts by weight of an organic and an inorganic pigment for color composition, 5 to 25 parts by weight of a solvent such as an aromatic hydrocarbon and a defoaming agent, And 4 to 8 parts by weight of additives.

The clear paint for forming the clear paint layer 40 is composed of 20 to 25 parts by weight of a polyester resin, 25 to 30 parts by weight of an isocyanate for a urethane curing system, 0.5 to 1 part by weight of a melamine resin 0.1 to 5 parts by weight of a pigment such as metallale paste or pearl for clear color composition, 20 to 30 parts by weight of a solvent such as aromatic hydrocarbon and the like and 4 to 5 parts by weight of an additive such as defoamer, curing accelerator and wax .

The polyester resin of the clear paint is a polyol having a number average molecular weight of 5000 to 6500 and an OH value of 40 to 60, which is advantageous for forming a sparkling appearance, and the isocyanate resin is a resin based on TDI (toluene diisocyanate). Such a resin becomes a post-coating film and blocks foaming. When the content of the polyester resin of the clear paint is 20 parts by weight or less, the effect of heat curing is small. When the content of the polyester resin exceeds 25 parts by weight, the effect of heat curing is too much. To the clear paint, 0.5 to 1 part by weight of an amide-based wax is added in order to form a wrinkle, which is a characteristic of sparkling coating. When the particles of the wax are large, the sparkling appearance of the coating film of the clear coating layer is broadly formed. When the particles of the wax are small, the sparkling appearance of the coating film of the clear coating layer is narrow.

The isocyanate resin is an isocyanate blocked with a toluene diisocyante base of Bayer Corporation or Baxenden, and various sparkling appearance can be formed depending on the type of isocyanate resin and the size of the amide wax particles.

The coating thickness of the base coating layer 30 may be variously sized, but it is preferable that the coating thickness of the clear coating layer 40 is 10 to 15 占 퐉, which is preferable for forming the sparkling appearance. When the coating thickness of the clear paint layer exceeds 15 mu m, the width of the valley and the acid which are the sparkling appearance become large, and the sparkling appearance is clogged when the coil is stored, which is not preferable.

The preferable PMT for forming the sparkling appearance is 210 to 224 ° C for the base paint and 232 to 241 ° C for the clear paint. The PMT (Peak Metal Temperature) is the highest temperature of the steel sheet for curing the paint coated on the steel sheet. When the PMT of the base paint is low, the base coating may have a high frictional force with the clear paint due to uncured coating, and the sparkling appearance may be somewhat dull. When the PMT of the base paint is high, the adhesion between the base coat and the clear coat may be poor When the PMT of the clear paint is low, the urethane hardening of the isocyanate resin and the polyester resin is insufficient and the water resistance and the solvent resistance may be weakened. When the PMT of the clear paint is high, the yellowing phenomenon of the clear coat film may occur.

The pearl and metallic paste of the clear paint are different from oil and inorganic pigments that can be dispersed in a resin by a solvent or the like and are simply a pigment mixed with a resin in the form of a mixture rather than being dispersed in a resin, It is close.

The solvent for the clear paint may include an ester solvent and an ether solvent in addition to an aromatic hydrocarbon solvent. In order to prevent a uniform film hardening and a roll mark scratch, a hydrocarbon solvent is used as much as possible, An ester solvent or an ether solvent may be used for the purpose of improving the transparency and the shelf life, but it is preferable to use 15 to 20 parts by weight of an aromatic hydrocarbon solvent, 3 to 5 parts of an ester solvent, And 3 to 5 parts by weight of an ether solvent are preferably used in combination. The lower limit of the compounding ratio of the clear paint to the solvent is a lower limit of the effect of the solvent, and the upper limit is a value giving a proper appearance effect at a predetermined thickness (10 to 15 mu m) of the clear coat.

Since the additive of the clear paint greatly influences the formation of the sparkling appearance depending on the type of defoaming agent for suppressing or eliminating bubbles in the coating film, it is preferable to use 2 to 3 parts by weight of a defoaming agent in which polyethylene wax is dissolved in XYLENE, 1 to 2 parts by weight of a curing accelerator (amine) for accelerating the curing reaction is used.

1, a color coated steel sheet having a sparkling appearance formed thereon is prepared using the coating material having the intermediate composition of the above-mentioned composition ranges of the base paint and the clear paint of the present invention, The results are shown in Table 1. [Table 1] < tb > < TABLE > Detailed test methods are described in ASTM related standards.

<Table 1>

Test Items Test result Test methods and devices Related Standards Polish 20 to 40 60 ° polisher ASTM D 523-89 Pencil hardness F ~ H Mitsubishi Uni Pencil ASTM D 3363-92 Solvent rub 10 times ↑ MEK, 2 kg load ASTM D 5402-93 T-bend 0T to 2T NO CRACK Vise, 180 °, 25 ° C ASTM D 4145-83 ASTM D 3794-94 Impact Good DuPont tester 1/2 "x 50 cm x 500 g ASTM D 2794-93 Erichsen Good Erichsen 6mm ASTM D 4146-83  Chemical resistance 5% HCl 24 hours Good 20 ℃ Normal temperature ASTM D 1308 5% NaOH 24h Good Abdominal aquatic Good 98 ℃ 1 hour -

On the other hand, in the case of a panel formed with a sparkling appearance, when the degree of curing is insufficient, it may be weak in water resistance and solvent resistance, so that the weight ratio of polyester and isocyanate used should be able to move within the composition ratio, 1 to 2 parts by weight of a curing accelerator blocked with bismuth carboxylate 2-ethylhexanoic acid should be used, since sparkling appearance may not occur depending on the case. In addition, the matters to be noted in the clear paint are that when a quencher such as Silca-GEL for gloss control is not properly formed, the sparkling appearance is not properly formed. If other additives besides the above-mentioned additive and isocyanate and polyester resin are applied, This is not done properly. In addition, when the pearl and metallic paste pigment for adjusting the color of the used clear paint are applied, the particle size should be less than 12 탆.

FIG. 2 is a photograph of a color coated steel sheet to which a base paint and a clear paint of the present invention are applied, the pearl pigment being used in a clear paint.

3 (a) and 3 (b) are photographs of a close-up enlarged photograph of a color coated steel sheet to which a base paint and a clear paint of the present invention are applied in an upper layer portion, wherein (a) shows a case in which a pearl pigment is used in a clear paint, ) Is a case where a metallic paste pigment is used in a clear paint.

1 is a schematic view of a color coated steel sheet to which the present invention is applied,

FIG. 2 is a photograph of a color painted steel sheet to which a base paint of the present invention and a clear paint (using a pearl pigment) are applied,

3 (a) and 3 (b) are photographs of a close-up enlarged photograph of a color coated steel sheet to which a base paint and a clear paint of the present invention are applied in an upper layer portion, wherein (a) shows a case in which a pearl pigment is used in a clear paint, ) Is a photograph in the case of using a metallic paste pigment in a clear paint.

DESCRIPTION OF THE RELATED ART [0002]

10: base layer (steel plate) 20: chrome coating layer

30: Base coating layer 40: Clear coating layer

Claims (6)

A chromium coating layer is formed by a coating type chromate treatment as a pretreatment for preventing corrosion and adhesion of a paint on a substrate layer (steel plate), and a base coating layer and a clear coating layer are sequentially formed on the chromium coating layer, In the sparkling-forming coating material forming the outer appearance, The base paint for forming the base coating layer comprises 40 to 50 parts by weight of a polyester resin as a main resin, 5 to 15 parts by weight of a melamine resin for curing the inside and the outside of the coated film, 1 to 3 parts by weight of a silicone resin for facilitating coloring, 0.1 to 10 parts by weight of an organic or inorganic pigment for color composition, 5 to 25 parts by weight of a solvent such as an aromatic hydrocarbon or the like and an additive such as a defoaming agent and a curing accelerator and wax 4 to 8 parts by weight, The clear paint for forming the clear paint layer comprises 20 to 25 parts by weight of a polyester resin, 25 to 30 parts by weight of an isocyanate for a urethane curing system, 0.5 to 1 part by weight of a melamine resin for improving coat hardening, 0.1 to 5 parts by weight of a pearl or metallic paste pigment for clear color composition, 20 to 30 parts by weight of a solvent such as aromatic hydrocarbon or the like, and 4 to 5 parts by weight of an additive such as defoamer, curing accelerator and wax Sparkling forming paints. delete The method according to claim 1, Wherein 0.5 to 1 part by weight of an amide wax is added to the urea curing system of the polyester resin and the isocyanate resin to the clear paint. The method according to claim 1 or 3, Wherein the polyester resin of the clear paint has a number average molecular weight of 5000 to 6500 and an OH value of 40 to 60, and the isocyanate resin is a resin based on TDI (toluene diisocyanate). A chromium coating layer is formed by performing a coating type chromate treatment as a pretreatment for preventing corrosion and improving the adhesion of the paint on the substrate layer (steel plate), and a base coating layer and a clear coating layer are formed so as to form a sparkling appearance on the chromium coating layer A color coated steel sheet formed sequentially, The base paint for forming the base coating layer comprises 40 to 50 parts by weight of a polyester resin as a main resin, 5 to 15 parts by weight of a melamine resin for curing the inside and the outside of the coated film, 1 to 3 parts by weight of a silicone resin for facilitating coloring, 0.1 to 10 parts by weight of an organic or inorganic pigment for color composition, 5 to 25 parts by weight of a solvent such as an aromatic hydrocarbon or the like and an additive such as a defoaming agent and a curing accelerator and wax 4 to 8 parts by weight, The clear paint for forming the clear paint layer comprises 20 to 25 parts by weight of a polyester resin, 25 to 30 parts by weight of an isocyanate for a urethane curing system, 0.5 to 1 part by weight of a melamine resin for improving coat hardening, 0.1 to 5 parts by weight of a pearl or metallic paste pigment for clear color composition, 20 to 30 parts by weight of a solvent such as aromatic hydrocarbon or the like, and 4 to 5 parts by weight of an additive such as defoamer, curing accelerator and wax Color coated steel plate coated with sparkling coating. The method of claim 5, Wherein the clear paint layer formed by the clear paint has a thickness of 10 to 15 占 퐉.

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