JPH0478530A - Colored top coat-coated heavy-duty corrosion-resistant steel material - Google Patents

Abstract

PURPOSE:To keep maintenance of a mark and aesthetic sence for a long time and to ensure low cost and quality for a long time by preparing an outer surface layer of a colored resin layer with a fluorinated resin and the colored resin layer except the outer surface layer with an acrylic urethane. CONSTITUTION:A colored top coat-coated heavy-duty steel material provides a primer layer 9, a urethane elastomer coating layer 10, an acrylic urethane layer 7 and a fluorinated resin 8 on the surface of a steel material 1. The primer layer 9 and a urethane elastomer coating layer 10 provide adhesiveness, water resistance, impact resistance and insulation resistance and the acrylic urethane layer 7 and a fluorinated resin layer 8 provide excellent performances on beauti ful appearance, weatherability and economical characteristics. pref. coating thicknesses of four layers are that the primer layer 9, the urethane elastomer coating layer 10, the acrylic urethane layer 7 and the fluorinated resin layer 8 are respectively 15-60mum,2-6mm,10-100mum and 5-20mum. The colored top coat coated heavy-duty steel material keeps maintenance of a mark and aesthetic sence for a long time and can react resins with relatively inexpensive prices.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is directed to the production of heavy corrosion-resistant steel materials coated with urethane elastomer or polyolefin resin used for structures, foundation piles, and earth shorings used in the ocean, ports, rivers, etc. Among these, it relates to colored urethane elastomer-coated heavy-duty anti-corrosion steel materials or colored olefin resin-coated heavy-duty anti-corrosion steel materials that are used exposed in the air, are colored in various colors to harmonize with the environment, and have excellent weather resistance.

(Prior Art) FIG. 3 shows a conventional coloring method in which an acrylic urethane layer 7 is colored on a urethane elastomer coating layer 10.

In the figure, 1 indicates a steel material, and 9 indicates a non-metallic primer.

FIG. 4 shows the material disclosed in Japanese Patent Application Laid-Open No. 172737/1983, which is a colored heavy corrosion-resistant steel material in which a polyolefin resin layer 5 is coated with a colored resin of acrylic urethane 7.

In the figure, 1 is a steel material, 2 is an inorganic primer layer, 3 is an organic primer layer, 4 is an adhesive layer, and 6 is a urethane primer layer.

Moreover, FIG. 5 shows the steel material of the invention shown in Japanese Patent Application No. 1-230595, which has a urethane elastomer coating layer 10.
Colored heavy protection 1 coated with fluorine resin 8 colored resin
It is a food steel material.

In the figure, 1 is a steel material, and 9 is a primer layer.

Further, FIG. 6 shows a steel material according to the invention shown in Japanese Patent Application No. 1-289142, which is a colored heavily corrosion-resistant steel material in which a polyolefin resin 5 is coated with a colored resin such as a fluororesin 8.

In the figure, 1 is a steel material, 2 is an inorganic primer layer, 3 is an organic primer layer, 4 is an adhesive layer, and 6 is a urethane primer layer.

(Problem to be solved by the invention) However, the colored heavy corrosion-resistant steel materials made by these methods have
There are also some drawbacks.

With the method of coloring acrylic urethane produced as shown in FIG. 3 or 4, it is difficult to maintain the sign integrity and aesthetic sense over a long period of time, and the color fades quickly over time.

Furthermore, the method of coloring the fluororesin produced as shown in FIG. 5 or 6 is not very economical because the resin is expensive.

The present invention solves the above-mentioned problems, and is a colored heavy-duty anti-corrosion steel material that maintains sign integrity and aesthetic sense over a long period of time, while also being able to cope with the cost of resin at a relatively low price.

(Means for Solving the Problems) The present invention is characterized in that an acrylic urethane layer containing a colored pigment is provided on a urethane elastomer coating layer, and a fluororesin containing a colored pigment is provided on the acrylic urethane layer. Heavy duty corrosion-resistant steel coated with a colored top coat.

In addition, after flame-treating the surface of the polyolefin resin layer and coating it with a urethane primer that has adhesive properties with the polyolefin resin, an acrylic urethane layer containing a colored pigment is provided, and a fluorine-based primer containing a colored pigment is applied on top of the acrylic urethane layer containing a colored pigment. This is a heavy corrosion-resistant steel material coated with a colored top coat, which is characterized by being coated with a resin.

FIG. 1 is an explanatory diagram of a heavy corrosion-resistant steel material coated with a colored top coat, in which the urethane elastomer of the present invention is used as an anti-corrosion coating layer, and acrylic urethane and fluororesin are coated thereon. FIG. 2 is an explanatory diagram of a heavy corrosion-resistant steel material coated with a colored top coat, in which a polyolefin resin is used as an anticorrosion liquid M layer, and acrylic urethane and a fluororesin are coated thereon.

The present invention is a heavy corrosion-resistant steel material coated with a colored top coat, in which a primer layer 9, a urethane elastomer coating layer 10, an acrylic urethane layer 7, and a fluororesin 8 are provided on the surface of a steel material 1, as shown in FIG.

The reason for this four-layer type is that the primer layer 9 and the urethane elastomer coating layer 10 provide good adhesion, water resistance, impact resistance, and insulation resistance, and the acrylic urethane layer 7 and fluororesin layer 8 provide good aesthetics. We place particular emphasis on aesthetics, weather resistance, and economy, and have given each of them excellent performance.

Preferred coating thicknesses for each of the four layers include a primer layer of 9 or 15 to 60 μm, and a urethane elastomer coating layer of 10 to 2 to 60 μm.
6II1m, acrylic urethane layer 7 is 10-100μ,
The fluororesin layer 8 has a thickness of 5 to 20 μm.

Further, in another embodiment of the present invention, as shown in FIG. 6. This is a heavy corrosion-resistant steel material coated with a colored top coat provided with an acrylic urethane layer 7 and a fluororesin 8.

The reason for this seven-layer type is that the inorganic primer layer 2, organic primer layer 3, adhesive layer 4, and polyolefin resin layer 5 have adhesion, water resistance, impact resistance, and insulation resistance. The urethane primer layer 6, the acrylic urethane layer 7, and the fluororesin layer 8 are designed to give particular importance to aesthetic appearance, weather resistance, and economic efficiency, and provide excellent performance to each of them.

The preferred coating thickness of each of the seven layers is 30 to 60μ in total for the inorganic primer layer 2 and the organic primer layer 3;
Adhesive layer 4 is 80 to 200μ, polyolefin resin layer 5
is 2-6 l11m, urethane primer layer 6 is 5-2
0μ, the acrylic urethane layer 7 has a thickness of 10 to 100μ, and the fluororesin layer 8 has a thickness of 5 to 20μ.

Next, each layer will be explained in detail.

Steel materials lined in the present invention include structural steel,
Steel pipe piles made of high tensile strength steel, weathering steel, sulfuric acid resistant steel, etc.
Examples include pipe sheet piles, steel sheet piles, H-shaped steel, square steel pipes, etc.

As shown in FIG. 1, the coating method is as follows: First, the anti-corrosion surface of the steel material is subjected to a blast treatment such as grid blasting or sand blasting to make it clean, and then the primer layer 9 is coated.

The primer layer 9 is an adhesion agent between the steel surface 1 and the urethane elastomer coating layer 0.

The coating material used is an organic resin primer such as an epoxy resin primer or a urethane resin primer, which has poor adhesion to the urethane elastomer covering ff/vio.

When applying these organic resin primers to steel materials,
An organic resin primer is applied to the steel material to a thickness of about 15 to 60 μm, preferably about 20 to 40 μm, using a coating method such as air spraying, airless spraying, or brush coating to achieve a uniform film thickness.

The coated film after application is cured naturally, but if it is to be cured in a short period of time, the steel material temperature is heated to a range of 30 to 60° C. to accelerate hardening.

The urethane elastomer coating layer 10 is a long-term corrosion protection layer.

The urethane elastomer may be any urethane obtained from an isocyanate compound and a polyol.

The coating thickness is: 2 to 6 mm, preferably 2.5 to 4 mm.
The coating is applied using an airless spray coating method, but in order to create a thick film with one application, the curing mechanism is such that after mixing the two liquids, it hardens within a few minutes. Therefore, the coating machine also supplies the two liquids separately. Just before dispensing, the two liquids are mixed and applied using a special sprayer.

The acrylic urethane layer 7 and the fluororesin 8 are a coating film that maintains aesthetic appearance.

The acrylic urethane layer 7 is of a type that is cured by a reaction between an acrylic polyol and an isocyanate, and can be colored in almost any color tone by adding a coloring pigment.

Pigment components include white (Titanium White), green (Cyanine Green), and yellow (Hansa Yellow).
, blue color (cyanine blue), red color (monolite fast red), gray color (titanium oxide and carbon black), etc., but the proportion of pigment components added in the paint is 1 to 50% by weight. is appropriate.

Further, the fluororesin 8 is of a type that is cured by a reaction between a fluororesin varnish and incyanate, and can be colored in almost any color tone by adding a coloring pigment.

Pigment components include white (titanium white), clean color (cyanine green), yellow (titanium yellow), blue (cobalt blue), red (yellow lead),
Although a gray color (titanium oxide and carbon black) is used, it is appropriate that the amount of pigment components added to the paint is 1 to 50% by weight.

Coloring pigments are not preferred because if the addition ratio is too low, the coloring will not be clear, and if the addition ratio is too high, the strength of the coating layer will decrease.

The coating thickness of the acrylic urethane layer 7 is preferably about 10 to 100 microns, preferably about 20 to 50 microns, and the thickness of the fluororesin layer 8 is about 5 to 20 microns, preferably about 10 to 15 microns.

The coating method is air spray, airless spray, brush coating, etc. to achieve a uniform film thickness.

Next, regarding FIG. 2 which is another embodiment of the present invention, first, the anti-corrosion surface of the steel material is cleaned by grid blasting, sand blasting, etc., and then the inorganic primer layer 2 and the organic Apply a primer layer 3.

These two buiramers are adhesives for maintaining long-term adhesive performance between the steel surface 1 and the adhesion side layer 4.

As coating materials, the inorganic primer layer 2 uses a chromic acid-based chemical conversion treatment agent, and the organic primer layer 3 uses an epoxy-based primer paint, which has excellent water resistance such as cathodic peeling resistance and hot water resistance. Use something similar. The total thickness of the inorganic primer layer 2 and organic primer layer 3 is 30 to 60μ.
A range of is appropriate.

The adhesive side layer 4 is an adhesive to strengthen the adhesive performance between the organic primer layer 3 and the polyolefin resin layer 5, and the coating material is a maleic anhydride modified polyolefin adhesive. The appropriate thickness is 80 to 100 microns in consideration of coating performance and economical efficiency. The polyolefin resin layer 5 is a long-term corrosion protection layer. The coating material is a copolymer mainly composed of hydrocarbons such as ethane, ethylene, and propylene, and the film thickness is suitably 2 to 3 mm.

The urethane primer layer 6 is an adhesive between the polyolefin resin layer 5 and the acrylic urethane layer 7. The urethane primer layer 6 is a urethane prepolymer containing terminal isocyanate groups obtained by reacting a polyol compound with a polyisocyanate compound having two or more isocyanate groups in the molecule in an excess equivalent amount relative to the hydroxyl groups of the polyol compound. .

The coating film thickness is 5 to 20 μm, preferably 5 to 10 μm, and it is best to apply a thin coating using an air spray coating method. If the film thickness exceeds 20 μm, it will take a long time to cure the coating film, and it will be hard to see. Even if it looks like this, the outer surface is cured in a peel-like manner, and the entire surface remains not completely cured, and since it is coated on top of it, problems such as poor adhesion with the fluororesin layer 8 occur.

In addition, before coating the polyolefin resin layer 5 with the urethane primer layer 6, the surface temperature of the polyolefin resin layer 5 is set to 60 to 90°C by applying a flame from a gas burner to the surface of the polyolefin resin layer 5. Preferably 70~
It is necessary to raise the temperature to 80° C. and partially oxidize the surface of the polyolefin resin layer 5 to create an activated state. The activated state may be created by a corona injection method or a dichromate/sulfuric acid mixed solution treatment method.

The acrylic urethane layer 7 and the fluororesin 8 are a coating film that maintains aesthetic appearance.

The acrylic urethane layer 7 is coated after the urethane primer layer 6 has been cured to the point where it is dry to the touch (a dry state where the paint does not adhere to the fingertip when you touch the coating film with your fingertip).

The acrylic urethane layer 7 and the fluororesin 8 are the same as the coating material shown in FIG. 1, and the coating method is also the same.

(Example) The present invention will be explained in more detail with reference to Examples.

In Figure 1, the outer diameter is 1016 mm and the wall thickness is 9.53 m1.
ll.

After cleaning the outer surface of a 1m long steel pipe for piles by grid blasting, 30μ of primer (urethane prepolymer 50% by weight, pigment 50%) was applied, and urethane elastomer (73% by weight polyol, isocyanate) was applied. 27% by weight) was applied to a 3 mm cloth, and acrylic urethane (
Acrylic polyol resin 53% by weight, pigment 26% by weight,
15μ of isocyanate (21% by weight) was applied, and on top of that, fluororesin (59% by weight of fluororesin, 271% by weight of pigment) was applied.
, isocyanate (14% by weight)) was applied in an amount of 15 μm.

Next, in Fig. 2, the outer diameter is 1016 mm and the wall thickness is 9.5 mm.
After cleaning the outer surface of a 3 mm, 1 m long steel pipe for piles by grid blasting, 40μ of a non-molecular primer (chromic acid type) and an organic primer (epoxy type) were applied, and a polyolefin resin (low density polyethylene) 2
．． 8 mm coating, heat the top with a propane burner for 5 minutes to raise the temperature, and then apply urethane primer (urethane polymer 50% by weight, toluene 50.1% by weight) 5 to 1
On top of that, 15μ of acrylic urethane (53% by weight of acrylic polyol resin, 26% of pigment, 21% by weight of isocyanate) was applied, and on top of that, fluororesin (
59% by weight of fluororesin, 27% by weight of pigment, 14% by weight of isocyanate) was applied in an amount of 15 μm.

Comparative examples are shown in FIGS. 3, 4, 5, and 6.

In FIG. 3, as in the present example, a brimer and a urethane elastomer were coated, and 25 μm of acrylic urethane was applied thereon. In addition, in FIG. 5, the primer urethane elastomer was coated and 25 μm of fluororesin was applied thereon in the same manner as in this example.

Also, in Figure 4, as in this example, an inorganic primer, an organic primer, an adhesive, a polyolein resin, a flame treatment on the resin surface, a urethane primer was applied, and 25μ of acrylic urethane was applied on top. . Also, in FIG. 6, in the same manner as in this example, an inorganic primer, an organic primer, an adhesive, a polyolefin resin, flame treatment of the resin surface, a urethane primer was applied, and 25 μm of fluororesin was applied thereon.

The coating performance and economic effects of the cladding tubes thus prepared are shown in Tables 1 and 2.

Table 1 shows the results of the EMMA water resistance mode test (accelerated test conducted in a mode that combines concentrated natural light irradiation and hot water immersion) of the test pieces of the inventive examples and comparative examples in Alisina, USA, compared to domestic natural exposure. As shown in the table, the results of a paint film evaluation test carried out (with severe paint film deterioration and rapid deterioration) and the price of ordinary paint are shown.
It has excellent weather resistance performance in terms of gloss retention, maintains heavy corrosion protection, and can also provide economic benefits.

In addition, Table 2 shows the results of a coating film performance evaluation test (Quezaometer test 500 hours) with a transparent top coat (paint without added coloring pigments). Ultraviolet rays pass through the top coat film, which tends to occur with transparent fluororesin, and surface chalking of the anticorrosion layer (a deterioration phenomenon that looks like dusting) occurs.
A good coating film can be obtained without the problem of interfacial peeling between the anticorrosive layer and the top coat.

Paint film performance evaluation test, test item EMMA water resistance mode test (test time 300,000 LYS) (E
Quatrial Mount with Mirro
rs for Acceleration: Natural light condensed irradiation) EMMA 50000LYSc 340℃ warm water Manzuke E
MM 850,000 LYS approx. 20 days 48H
r Approximately 20 days 40℃ warm water soaking 1 cycle 48 hours (approximately 44 days) Note) 3 cycles (300,000 LYS) will reduce the domestic natural exposure to approximately 2
Year equivalent LYS (Langleys) = ICai/
cm'2, test piece preparation Test piece; Iron plate (100X 300) Painting; Air spray (colored top coat) 3, Test details 1) Color difference ■Test method Measurement: 2-light source spectrophotometer Color difference was measured using a color difference meter. The brightness), a, and b (hue) values of the paint film on the painted test piece were measured, and ΔE (color difference) = ΔL2 + Δa2 + Δb.

Calculated by.

■Evaluation ○ 0-5.0 × More than 5.0 2) Gloss retention rate ■Test method Measurement; Gloss meter 60' Gloss ■Evaluation 70-100 Less than 70 3) Adhesion ■Test method Base grain tape peeling 1 ! ! (1mm width) ■Review
Value 98/100 to 100/100 9B/100 or less 0240 times or less The problems that made it difficult to maintain an aesthetic sense or the fact that it was expensive and not very economical have been improved, and it has become possible to ensure quality over a long period of time at a low price.

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams of heavy corrosion-resistant steel materials coated with a colored top coat of the present invention, and Figures 3, 4, 5, and 6 are conventional colored heavy-duty corrosion-resistant steel materials coated with urethane elastomer or colored. FIG. 2 is an explanatory diagram of a heavy corrosion-resistant steel material coated with a polyolefin resin. 1... Steel material 2... Inorganic primer layer 3... Organic primer layer 4... Adhesive layer 5... Polyolefin resin layer 6... Urethane primer layer 7... Acrylic urethane layer 8 ... Fluorine resin layer 9... Buiramer layer 10.
...Urethane elastomer resin layer and 4 others Fig. 1 Fig. 4 Fig. 5 Fig. 3 Fig. 6

Claims (1)

[Scope of Claims] 1. A colored heavy duty corrosion-resistant steel material in which a urethane elastomer or a polyolefin resin is used as an anti-corrosion coating layer, and a colored resin is coated on the coating layer, and the outer surface layer of the colored resin layer is made of a fluorine-based resin; A heavy corrosion-resistant steel material coated with a colored top coat, characterized in that the colored resin layer other than the outer surface layer is made of acrylic urethane. 2. A heavy corrosion-resistant steel material coated with a colored top coat, characterized in that the surface of the steel material is coated with a primer and a urethane elastomer to form an anti-corrosion coating layer, and colored resins such as acrylic urethane and fluororesin are laminated thereon. 3. A colored top characterized by coating the surface of a steel material with an inorganic primer, an organic primer, an adhesive, and a polyolefin resin to form an anticorrosion coating layer, and a urethane primer, an acrylic urethane, and a fluororesin are laminated thereon. Coated heavy corrosion-resistant steel material.