JPH03293425A - Steel sheet pile with heavy rust-proof covering and its manufacture - Google Patents

Abstract

PURPOSE:To greatly raise the water-resistant adhesion of colored paint films and heavy rust-proof covering by a method in which a polyolefin-coated steel sheet pile is subjected to a corona-discharge treatment and coated with a urethane primer and a fluoro resin paint. CONSTITUTION:A steel sheet pile 3 covered with an electron rays-bridged polyolefin layer, having an electron rays-bridged polyolefin layer 2 of 1-10mm thickness, containing 0.05-5.0wt.% antioxidant, on its outermost layer, is passed between roll electrodes 10, 12, and 14 for corona-discharge treatment. The sheet pile 1 so treated is coated with a urethane primer or modified polyolefin primer 26 of a thickness of 5-10mum and with a color paint 4 such as various color fluoro resin paint of a thickness of 10-100mum. The sheet pile 1 covered with heavy rust-proof covering is free of the blister of the fluoro resin paint film and has sufficiently high adhesion between the paint film and the electron rays- bridged black-color low-density polyethylene film. The adhesion between the color paint film and the heavy rust-proof covering in relation to water can thus be greatly raised.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to heavy corrosion-resistant coated steel sheet piles used for steel structures used in oceans, rivers, ports, etc. The present invention relates to a heavily anti-corrosion coated steel sheet pile that has a colored coating film in various colors with excellent properties, is aesthetically pleasing, and has excellent water-resistant adhesion between the colored coating film and the heavy anti-corrosion coating, and a method for producing the same.

(Prior Art) Conventional polyolefin-coated steel materials, such as polyolefin-coated steel sheet piles, are coated with black polyethylene, which has excellent corrosion resistance. However, due to the recent increase in market needs for aesthetic landscapes of steel structures such as urban landscapes, rivers, and ports, heavy corrosion-resistant N steel sheet piles are being developed that are colored in various colors to harmonize with the environment and have excellent weather resistance. Development is desired. To meet such needs, for example, as shown in FIG.
There is a proposal for a heavy anti-corrosion coated steel material characterized by sequentially laminating a urethane primer layer 24 and a fluororesin layer 25 containing a colored pigment. Kuninaka 1 indicates a steel sheet pile or steel material, 20 indicates an inorganic brimer, 21 indicates an organic brimer, and 22 indicates an adhesive layer.

(Problem to be Solved by the Invention) However, in the conventional heavy anti-corrosion coated steel material shown in FIG. There is a problem in that the adhesive force between the layer 25 gradually decreases and blisters occur in the fluororesin layer 25 containing the colored pigment.

(Means for Solving the Problems) As a result of intensive studies to solve the above-mentioned problems, the present inventors added an antioxidant with a concentration of 005 to 50% to the outermost layer of the surface of the steel sheet pile.
The surface of the steel sheet pile coated with electron beam crosslinked polyolefin, which contains electron beam crosslinked polyolefin containing % by weight and whose outer surface has been subjected to corona discharge treatment, is colored with various colors of fluorine paint, acrylic-silicon paint, acrylic-urethane paint, etc. Laminating paint films, or applying urethane primer or modified polyolefin primer to the surface of polyolefin-coated steel sheet piles, and then applying colored paints such as fluorine paints, acrylic-silicon paints, acrylic-urethane paints, etc. in various colors. The inventors have discovered that the above-mentioned problems can be solved by laminating films, leading to the present invention.

That is, as shown in FIGS. 1 and 2, the present invention provides an electronic material containing 0.05 to 5.0% by weight of an antioxidant in the outermost layer of the surface of a steel sheet pile 1, and having the outer surface treated with a corona discharge. It is characterized in that a colored paint coating 4 of various colors such as fluorine paint, acrylic-silicon paint, acrylic-urethane paint, etc. is laminated on the surface of an electron beam crosslinked polyolefin coated steel sheet pile having wire crosslinked polyolefin 2. Heavy duty anti-corrosion coated steel sheet pile and, as shown in Fig. 4, electron beam crosslinked polyolefin coated steel sheet pile having electron beam crosslinked polyolefin containing 0.05 to 5.0% by weight of antioxidant in the outermost layer of the surface of the trough of the steel sheet pile. 3 is subjected to corona discharge treatment with a continuously rotating first rolled electrode 10 on the surface 9 of the web portion of the coating while being transferred by a table roller 5, and then on the surface 11 of the flange portion of the coating. The surface 13 of the claw portion is subjected to corona discharge treatment using the second roll type electrode 12, and then the corona discharge treatment is applied to the surface 13 of the claw portion using the third roll type electrode 14 that rotates continuously. A method for producing heavy duty anti-corrosion coated steel sheet piles characterized by coating with a colored paint such as a paint or an acrylic-urethane paint, and as shown in FIG.
An electron beam crosslinked polyolefin coated steel sheet pile 3 in which the peaks of the steel sheet pile are coated with an electron beam crosslinked polyolefin containing 0% by weight,
The surface 15 of the web portion of the coating is subjected to a corona discharge treatment with a continuously rotating first rolled electrode 16 while being transferred and conveyed on a table roller 5, and then the surface 17 of the flange portion
After applying corona discharge treatment using a continuously rotating second roll-type electrode 18, a heavy-duty material is coated with colored paints such as fluorine-based paints, acrylic-silicon-based paints, and acrylic-urethane-based paints in various colors. As shown in FIGS. 7 and 8, the method for manufacturing anti-corrosion coated steel sheet piles includes 0.05 to 5.0% by weight of an antioxidant in the outermost layer of the surface of the steel sheet pile 1, and corona discharge on the outer surface. After applying a urethane primer or a modified polyolefin primer 26 to the surface of the electron beam crosslinked polyolefin-coated steel sheet pile having the treated electron beam crosslinked polyolefin 2, various colors of fluorine paint, acrylic-silicon paint, and acrylic-urethane paint are applied. As shown in FIG. 4, the outermost layer of the valley surface of the steel sheet pile is coated with 0.05 to 5.0 of an antioxidant. An electron beam cross-linked polyolefin coated steel sheet pile 3 having an electron beam cross-linked polyolefin containing % by weight is transferred by a table roller 5, and corona is applied to the surface 9 of the web portion of the coating by a first rolling electrode 10 that continuously rotates. discharge treatment, then corona discharge treatment on the surface 11 of the flange portion with a second roll-type electric wire 8i12 that rotates continuously, and then apply corona discharge treatment on the surface 13 of the claw portion with a third roll-type electric wire 8i14 that continuously rotates.
Heavy-duty corrosion protection is characterized by applying a urethane primer or modified polyolefin primer after corona discharge treatment, and then applying colored paints such as fluorine paints, acrylic-silicon paints, and acrylic-urethane paints in various colors. Method for producing coated steel sheet piles and electron beam crosslinked polyolefin coating in which the peaks of steel sheet piles are coated with electron beam crosslinked polyolefin containing 0.05 to 5.0% by weight of an antioxidant in the outermost layer, as shown in FIG. While conveying the steel sheet pile 3 on the table roller 5, the surface 15 of the web portion of the coating is subjected to a corona discharge treatment with a continuously rotating first rolled electrode 16, and then the surface 17 of the flange portion is continuously treated with a corona discharge treatment. After corona discharge treatment with the second rotating electrode 18, a urethane primer or modified polyolefin primer is applied, and then colored paints such as fluorine paints, acrylic-silicon paints, acrylic-urethane paints, etc. of various colors are applied. This is a method for manufacturing heavy-duty anti-corrosion coated steel sheet piles, which is characterized by coating them with.

Hereinafter, the present invention will be explained in detail.

The steel sheet pile used in the present invention is a steel sheet pile made of alloy steel such as carbon steel and stainless steel. In addition, in order to improve the corrosion resistance of steel sheet piles, zinc is applied to the valley and peak surfaces of steel sheet piles.
Plating of aluminum, nickel, etc., alloy plating of zinc-iron, zinc-aluminum, zinc-nickel-cobalt, etc., or dispersion plating in which fine inorganic particles such as silica, titanium oxide, etc. are dispersed in the plating or alloy plating, etc. However, this does not pose any hindrance to the present invention.

As the electron beam cross-linked polyolefin coated steel sheet pile, 1J3
As shown in the figure, the surface of the steel sheet pile is blasted using grid blasting, sandblasting, etc. to remove rust, and then the surface is treated with a chromate treatment agent and epoxy primer, and then the back side of the electron beam crosslinked polyolefin sheet is coated with maleic anhydride, etc. Electron beam crosslinked polyolefin coated steel sheet piles manufactured by pasting a sheet laminated with a modified polyolefin adhesive obtained by modifying polyolefins can be used. A cross-linked polyolefin is sufficient, and steel sheet piles coated with electron beam cross-linked polyolefin can be used, which have been treated with conventionally known chromate treatment agents, epoxy primers, phosphate treatments, silane coupling agents, etc. alone or in combination with these base treatments. Its use does not pose any hindrance to the present invention.

The electron beam crosslinked polyolefin coated on the outermost layer of the electron beam crosslinked polyolefin coated steel sheet pile contains no antioxidant.
．． 05 to 5.0% by weight of polyolefins such as low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, polypropylene, etc., and ethylene-propylene block or random combinations. A sheet formed from a polymer or a polyolefin copolymer such as a polyamide-propylene block or random copolymer can be used. If the antioxidant content of the electron beam crosslinked polyolefin coating is less than 0.05% by weight or more than 5.0% by weight, the electron beam crosslinked polyolefin coating and various colors of fluorine-based, acrylic-silicon based, etc. Alternatively, the adhesion between the acrylic and the urethane paint film decreases, and blisters occur in the paint film.

Next, the corona discharge treatment applied to the outer surface of the electron beam crosslinked polyolefin coated steel sheet pile will be described. The corona radiation N'A principle is that colored paints of various colors can be applied to the surface of the electron beam crosslinked polyolefin coating after discharge treatment without repelling, and that they can be cured to form a coating film. It is necessary to apply discharge treatment uniformly to the outer surface.

For this purpose, a method using a roll-type electrode coated with a silicone resin that rotates continuously can be used.

If the outer surface of the electron beam crosslinked polyolefin coating is not uniformly treated with corona discharge, the adhesion between the electron beam crosslinked polyolefin coating and various colored paint coatings will decrease after the marine practical test, and the paint coating will deteriorate. Blisters occur.

Regarding the degree of corona discharge treatment, for example, in the case of electron beam crosslinked low-density polyethylene, high-density polyethylene, or ethylene-propylene block copolymer coating, the "wetting test method for polyethylene and polypropylene films" specified in JIS 6768 is used. After corona discharge treatment,
It is desirable to carry out the discharge treatment so that the "wetting index (surface tension)" becomes 366 yn/cm or more. If the "wetting index (surface tension)" is less than 366 yn/cm, the adhesion between the electron beam crosslinked polyolefin coating and the colored paint film of various colors decreases after the marine practical test, and the colored paint Blisters appear on the paint film.

Next, the urethane primer and modified polyolefin primer to be laminated on the surface of the corona discharge-treated electron beam crosslinked polyolefin-coated steel sheet pile will be explained with reference to FIG. 9. The urethane primer used in the present invention has a molecular weight of 400 to 2000 and has a terminal isocyanate obtained by the reaction of a polyol compound having two or more hydroxyl groups in the molecule with a polyisocyanate compound having an isocyanate group in the molecule. Group-containing urethane prepolymers are preferred. In addition, from the viewpoint of water resistance, the modified polyolefin primer is preferably a liquid primer prepared by diluting a modified polyolefin whose main components are ethylene-vinyl acetate copolymer, acid anhydrides such as maleic anhydride, etc. with a solvent, and general commercially available products. For example, Thermotac E2 manufactured by Chugoku Paint Co., Ltd.
00, Thermotac E300, Thermotac E500, etc. can be used.

Next, the colored paint to be laminated on the surface of the electron beam crosslinked polyolefin coated steel sheet pile treated with corona group 1 will be described. From the viewpoint of weather resistance, the paints include commercially available acrylic-urethane paints such as NY Borin in various colors manufactured by Shinto Paint Co., Ltd., Silica Lac in various colors manufactured by Chugoku Paint Co., Ltd., and silica lacquer in various colors manufactured by Shinto Paint Co., Ltd. Commercially available acrylic-silicon paints such as Ceraforte in various colors, Duflon in various colors manufactured by Nippon Paint Co., Ltd., and Syntoflon in various colors manufactured by Shinto Yoyo Co., Ltd. can be used. desirable.

Next, a method for manufacturing a heavily anti-corrosion coated steel sheet pile according to the present invention will be explained. As shown in FIG. 4, a steel sheet pile 3 coated with an electron beam crosslinked polyolefin having an electron beam crosslinked polyolefin containing 0.05 to 5.0% by weight of an antioxidant on the outermost layer of the surface of the trough of the steel sheet pile is placed on a table roller 5. while transporting the coating with a corona discharge treatment on the surface 9 of the web portion of the coating with a continuously rotating first rolled electrode 10, and then on the surface 11 of the flange portion with a continuously rotating second rolled electrode. 12, and then the surface 13 of the claw portion is subjected to corona discharge treatment using a third roll-type electrode 14 that rotates continuously, and then fluorine-based paints of various colors, acrylic-silicon-based paints, acrylic-urethane-based paints are applied. The heavily anti-corrosion coated steel sheet pile according to the present invention is manufactured by applying a colored paint such as paint. Another method of the present invention is to apply a urethane primer or a modified polyolefin primer after corona discharge treatment,
Fluorine paints in various colors, acrylic-silicon paints,
The heavily anti-corrosion coated steel sheet pile according to the present invention is manufactured by coating with a colored paint such as an acrylic-urethane paint. In addition, in the case of coating the peaks of steel sheet piles, as shown in Figure 5, the tops of the steel sheet piles were coated with electron beam cross-linked polyolefin containing 0.05 to 5.0% by weight of an antioxidant in the outermost layer. The N steel sheet pile 3 covered with electron beam crosslinked polyolefin is subjected to a corona discharge treatment using a first rolling electrode 16 that continuously rotates the surface 15 of the web portion of the coating while being transferred and conveyed on a table roller 5, and then the flange After the surface 17 of the part is subjected to corona discharge treatment with a continuously rotating second roll electrode 18, or after corona discharge treatment, a urethane primer or modified polyolefin primer is applied, and fluorine-based paint of various colors, acrylic paint is applied. A heavily corrosion-protected N steel sheet pile according to the present invention is manufactured by applying a colored paint such as a silicone paint or an acrylic-urethane paint.

Regarding the degree of corona discharge treatment of the surface coated with electron beam crosslinked polyolefin, for example, in the case of electron beam crosslinked low density polyethylene, high density polyethylene, or ethylene propylene block copolymer coating, "polyethylene and polypropylene" specified in JIS K6768 is used. In Figures 4 and 5, a silicon-based resin that is driven and rotated is subjected to discharge treatment so that the "wetting index (surface tension)" after corona discharge treatment becomes 36 dyn/cm or more. A large number of coated roll-type electrodes are arranged on the web section, flange section, and claw section, but if it is difficult to achieve uniform corona discharge treatment due to the conveyance speed of the steel sheet pile, two roll-type electrodes may be arranged. If you list more than one book, the "wetting index (surface tension)" is 3.
It should be at least 6 dyn/cm and uniform.

A roll-type electrode that is driven and rotated is effective in making the corona discharge treatment uniform.

(Function of the Invention) The heavy anti-corrosion coated rectangular steel pipe pile of the present invention has an antioxidant applied to the outermost layer of the outer surface of the steel sheet pile 1, as shown in FIGS. 1, 2, 7, and 8. Urethane primer or modified polyolefin primer 26 is applied to the outer surface of the electron beam crosslinked polyolefin coated steel sheet pile 3 having the electron beam crosslinked polyolefin 2 containing 05 to 5.0% by weight and whose outer surface has been subjected to corona discharge treatment. This is a heavily anti-corrosion coated steel sheet pile on which a colored paint film 4 of various colors such as fluorine paint, acrylic-silicon paint, acrylic-urethane paint, etc. is laminated. Furthermore, as shown in FIGS. 4 and 5, the method for manufacturing heavy anti-corrosion coated steel sheet piles of the present invention includes electron beam crosslinking containing 0.05 to 5.0% by weight of an antioxidant in the outermost layer of the surface of the steel sheet piles. After the electron beam cross-linked polyolefin-coated steel sheet pile 3 containing polyolefin is transferred on a table roller, the surfaces of the web portion, flange portion, and claw portion of the surface are each subjected to corona discharge treatment using continuously rotating rolling electrodes. Alternatively, after corona discharge treatment, a urethane primer or a modified polyolefin primer is applied, and colored paints such as fluorine paints, acrylic-silicon paints, and acrylic-urethane paints of various colors are applied.

In addition, in FIGS. 3 and 9, the electron beam crosslinked polyolefin 2 has a film thickness of 1 to 10 mm, the urethane primer or modified polyolefin primer 26 has a film thickness of 5 to 10 μm, fluorine-based paints of various colors, acrylic-silicon-based Paint, colored paint such as acrylic-urethane paint @4 is 10
Good results are obtained with a film thickness of ~100μ.

(Example) Example I While transporting a FSP III type steel sheet pile with a length of 5500 mm on a table roller, the valley surface was subjected to grid blasting to remove rust, and a chromate treatment agent was applied to reduce the total amount of chromium deposited. 350 mg/m2 and baked, spray coated with epoxy primer to a film thickness of 50 μm and cured by heating, then laminated with maleic anhydride-modified straight-line low-density polyethylene adhesive. A wire-crosslinked black low-density polyethylene sheet was attached to obtain an electron beam-crosslinked low-density polyethylene-coated square steel sheet pile. The content of antioxidant in the electron beam crosslinked black low density polyethylene coating is 0.331% by weight, and the film thickness of the electron beam crosslinked black low density polyethylene coating is 2.5 mm. Maleic anhydride modified linear low density polyethylene. The film thickness of the adhesive was 200μ. The electron beam cross-linked black low-density polyethylene-coated steel sheet pile obtained as described above was transported by table rollers 5 (transport speed + 2.0 m/m1n) as shown in Fig. 4.
The surface 9 of the web portion of the coating is subjected to a corona discharge treatment with a first rolled electrode 10 that rotates continuously, and then the surface 11 of the flange portion is treated with a second rolled electrode 12 that continuously rotates. After corona discharge treatment is performed on the surface 13 of the claw portion using a third rolling electrode 14 that rotates continuously, a fluorine-based paint (Duflon manufactured by Nippon Paint Co., Ltd., color tone Marcel value: 10B) is applied. 5/10
(blue)) was spray-painted to a film thickness of 30 μm to obtain a heavily anti-corrosion coated steel sheet pile (■) according to the present invention. The "wetting index (surface tension)" of the electron beam crosslinked black low density polyethylene coated surface after the corona discharge treatment was 55 dyn/cm. As a comparison material, the surface of the electron-beam crosslinked black low-density polyethylene-coated steel sheet pile obtained as described above was heated with a propane burner for 5 minutes to raise the temperature to 70 to 80°C, and a urethane primer (urethane polymer) was applied to the surface. 50% by weight, toluene 50% by weight), and then apply 5 to 10μ of fluororesin paint (60% by weight fluororesin, 26% by weight pigment, 14% by weight isocyanate, Marcel value of color tone).
10B 5/10) was applied to obtain a comparison heavy anti-corrosion coated steel sheet pile ■. The heavy anti-corrosion coated steel sheet pile ■ according to the present invention obtained as described above and the comparison heavy anti-corrosion coated steel sheet pile ■ were subjected to a three-year marine practical use test. In addition to observing the presence or absence of blisters on the film, an adhesion test between these colored coating films and the electron beam crosslinked black low-density polyethylene coating was conducted. The test results are shown in Table 1.

As is clear from the results in Table 1, the heavy-duty anti-corrosion coated steel sheet pile ■ according to the present invention shows a higher level of fluorine-based paint coating even after a three-year marine practical use test compared to the comparative heavy-duty anti-corrosion coated steel sheet pile ■. No blistering occurs, and the adhesion between the fluorine-based paint film and the electron beam crosslinked black low-density polyethylene coating is sufficiently high.
The water-resistant adhesion between the colored paint film and heavy anti-corrosion coating is extremely excellent.

Example 2 The content of antioxidant in the low-density polyethylene coating of the electron beam cross-linked low-density polyethylene-coated steel sheet pile used for manufacturing the heavy corrosion-resistant coated rectangular steel pipe pile of the present invention in Example 1 was 0.05 to 5% by weight. Heavy anti-corrosion coated steel sheet piles ① to ② according to the present invention were manufactured in the same manner as in Example 1, with changes within the range. As a comparative example,
Using the same method as in Example 1, the content of the antioxidant was 0.0.
Comparative heavy-duty anti-corrosion coated steel sheet pile (1) and comparative heavy-duty anti-corrosion coated steel sheet pile (2) having the antioxidant content of 6.0 were manufactured. The heavy-duty anti-corrosion coated steel sheet pile obtained as above and the comparison heavy-duty anti-corrosion coated steel sheet pile were subjected to the same three-year marine service test as in Example 1, and after the test was completed, fluorine-based paint 1j! In addition to observing the presence or absence of blisters in the film or fluororesin paint coating,
Adhesion tests were conducted between these colored coatings and electron beam crosslinked low density polyethylene coatings.

The test results are shown in Table 1.

As is clear from the results in Table 1, if the antioxidant content in the electron beam crosslinked polyolefin coating of the heavy corrosion protection coated steel sheet pile according to the present invention is in the range of 0.05 to 5% by weight,
Even after a year of marine practical use tests, there was no blister formation in the fluorine-based paint film, and the adhesive strength between the fluorine-based paint film and the low-density polyethylene coating was sufficiently high. However, when the content of the antioxidant is 0.01% by weight and 6% by weight, blisters occur in the fluorine-based paint film, and the fluorine-based paint film and electron beam crosslinked low-density polyethylene The adhesion between the coating and the coating is also reduced.

Example 3 Using the same method as in Example 1, the degree of corona discharge treatment applied to the electron beam low-density polyethylene coating was changed to 36 to 70 dyn/cm in terms of "wetting index (surface tension)" to obtain heavy corrosion protection according to the present invention. Coated steel sheet piles ■ to ■ were manufactured. As a comparative example, a comparative heavy anti-corrosion coated steel sheet pile (2) was produced in the same manner as in Example 1, in which the degree of corona discharge treatment was 34 dyn/cm in terms of "wetting index (surface tension)". The heavy-duty anti-corrosion coated steel sheet pile obtained as described above and the comparison heavy-duty anti-corrosion coated steel sheet pile were subjected to the same 3-year ocean service test as in Example 1, and after the test was completed,
In addition to observing the presence or absence of blistering in the fluorine-containing paint film or fluororesin paint film, an adhesion test was conducted between these colored paint films and the electron beam crosslinked low-density polyethylene coating. The test results are shown in Table 1.

As is clear from the results in Table 1, if the degree of corona discharge treatment used in the present invention is 35 to 70 dyn/cm in terms of "wetting index (surface tension)", fluorine-containing There is no occurrence of blisters in the paint film, and the adhesion between the fluorine-based paint film and the low-density polyethylene coating is sufficiently high. However, the "wetting index (surface tension)" is 3
At 46 yn/cm, blisters occur in the fluorine-based paint film, and the adhesive strength between the fluorine-based paint film and the electron beam crosslinked low-density polyethylene coating also decreases.

Example 4 In the same manner as in Example 1, the electron beam crosslinked low density oleethylene coated steel sheet pile was replaced with an electron beam crosslinked high density polyethylene coated steel sheet pile and an electron beam crosslinked ethylene propylene block copolymer coated steel sheet pile. Heavy-duty anti-corrosion board ffwi sheet piles ■ to ■ according to the invention were manufactured. The heavy anti-corrosion coated steel sheet piles obtained as described above and the comparison heavy anti-corrosion coated N steel sheet piles were subjected to the same 3-year marine use test as in Example 1, and after the test, fluorine-based paint coating or fluororesin paint coating was applied. In addition to observing the presence or absence of blisking, an adhesion test was conducted between these colored coatings and an electron beam crosslinked high-density polyethylene coating and an electron beam crosslinked ethylene propylene block copolymer coating. The test results are shown in Table 1J1.

As is clear from the results in Table 1, the heavy corrosion protection coated rectangular steel pipe pile according to the present invention has high corrosion resistance, regardless of the type of polyolefin in the electron beam crosslinked polyolefin coated steel sheet pile used for its manufacture.
Even after three years of actual marine use tests, no blisters occurred in the fluorine-based paint film, and the adhesion between the fluorine-based paint film and the low-density polyethylene coating was sufficiently high.

Example 5 While transporting a FSP III type steel sheet pile with a length of 5500 mm on a table roller, the surface of the mountain part was subjected to grid blasting to remove rust, and the chromate treatment agent was applied to the total chromium adhesion amount to 350 mg/m2. The epoxy primer was spray-coated to a film thickness of 50 μm and cured by heating, and then a maleic anhydride-modified linear low-density polyethylene adhesive was laminated with electron beam cross-linked black low-density polyethylene. The sheet was attached to obtain an electron beam crosslinked low density polyethylene coated square steel sheet pile. The content of antioxidant in the electron beam crosslinked black low density polyethylene coating was 0.3% by weight, the film thickness of the electron beam crosslinked black low density polyethylene coating was 2.5 mm, and the maleic anhydride modified linear low density The film thickness of the polyethylene adhesive was 200μ. The electron beam cross-linked black low-density polyethylene coated steel sheet pile obtained as described above is transported by table rollers 5 (transport speed: 2.0 m/win) as shown in FIG.
/ while the surface 15 of the web portion of the coating is subjected to corona radiation treatment with a continuously rotating first rolled electrode 16, and then the surface 17 of the flange portion is subjected to corona radiation treatment with a continuously rotating second rolled electrode 18. After corona discharge treatment, the acrylic-silicon and acrylic-urethane colored paints shown in Table 2 were applied to a thickness of 30 μm to produce heavy anti-corrosion coated steel sheet piles 1 to 0 according to the present invention. The heavy anti-corrosion coated square steel sheet pile obtained as described above was subjected to the same 3-year marine practical test as in Example 1, and after the test was completed, the presence or absence of blisters in the fluorine-based paint film or fluororesin paint film was observed. At the same time, an adhesion test was conducted between these colored coatings and an electron beam crosslinked low density polyethylene coating.

The test results are shown in Table 1.

As is clear from the results in Table 1, even when acrylic-silicon-based or acrylic-urethane-based colored paints were used, there was no occurrence of blisters in the colored paint film even after three years of actual marine usage tests. Moreover, the adhesion between the colored paint film and the electron beam crosslinked low density polyethylene coating is sufficiently high.

Example 6 F S P III type steel sheet pile with a length of 5500 mm was transported on a table roller, and the valley surface was subjected to grid blasting to remove rust, and a chromate treatment agent was applied to the steel sheet pile until the total chromium adhesion amount was 350 mg/m' The epoxy primer was spray-painted to a film thickness of 50 μm and cured by heating, and then a maleic anhydride-modified linear low-density polyethylene adhesive was laminated with an electron beam cross-linked black low-density adhesive. A polyethylene sheet was attached to obtain an electron beam cross-linked low-density polyethylene-coated square steel sheet pile. The content of antioxidant in the electron beam crosslinked black low density polyethylene coating is 0.3% by weight, and the film thickness of the electron beam crosslinked black low density polyethylene coating is 2.5 mm. The film thickness of the adhesive was 200μ. The electron beam cross-linked black low-density polyethylene-coated steel sheet pile obtained as described above was transported by table rollers 5 (conveying speed: 2.0m/m1n) as shown in FIG.
Meanwhile, the surface 9 of the web portion of the coating is subjected to a corona discharge treatment with a continuously rotating first rolled electrode 10, and then the surface 11 of the flange portion is subjected to a corona discharge treatment with a continuously rotating second rolled electrode 12. After the electric discharge treatment, the nail surface 1
After corona discharge treatment with the third roll-type electric i14 that rotates continuously, 5 to 10μ of a modified polyolefin primer (Thermotac E300, manufactured by Chugoku Paint Co., Ltd.) is applied, and a fluorine-based paint (manufactured by Nihon Baint Co., Ltd.) is applied. duflon,
A heavy anti-corrosion coated steel sheet pile (2) according to the present invention was obtained by spray painting a coated sheet with a Marcel color (Marcel value: 10B 5/10 (blue)) to a film thickness of 30 μm. The "wetting index (surface tension)" of the electron beam crosslinked black low density polyethylene coated surface after the corona discharge treatment was 55 dyn/cm. As a comparison material, the surface of the electron beam crosslinked black low density polyethylene coated steel sheet pile obtained as described above was heated with a propane burner for 5 minutes to raise the temperature to 70 to 80°C, and a urethane primer (urethane primer) was applied to the surface. Apply 5 to 10 microns of fluororesin paint (60% by weight of fluororesin, 261i amount of pigment, 14% by weight of isocyanate, Marcel value of color tone: IOB).
5/10) was coated with 30 μm of paint to obtain comparatively heavy anti-corrosion coated steel sheet piles. The heavy anti-corrosion coated steel sheet pile ■ according to the present invention obtained as described above and the comparison heavy anti-corrosion coated steel sheet pile ■ were subjected to a three-year marine practical use test. In addition to observing the presence or absence of blisters on the membrane, check the coloring of these! ! ! Adhesion test between membrane and electron beam cross-linked black low-density polyethylene coating [Substrate test:
In accordance with JIS K 5400, the adhesive strength was expressed on a scale of 0 to 10 (out of 10). Third test result
Shown in the table.

As is clear from the results in Table 's3, the heavy-duty anti-corrosion coated steel sheet pile according to the present invention, compared to the comparative heavy-duty anti-corrosion coated steel sheet pile,
Even after 3 years of marine practical use tests, there was no blistering of the fluorine-based paint film, and the adhesion between the fluorine-based paint film and the electron beam cross-linked black low-density polyethylene coating was sufficiently high, and the colored paint film and heavy corrosion protection were maintained. The water-resistant adhesion between the coatings is extremely excellent.

Example 7 The content of antioxidant in the low-density polyethylene coating of the electron beam cross-linked low-density polyethylene-coated steel sheet pile used for manufacturing the heavy corrosion-resistant coated square steel pipe pile of the present invention in Example 6 was 0.05 to 5% by weight. Single anti-corrosion coated steel sheet piles (1) to (2) according to the present invention were manufactured in the same manner as in Example 6, with the changes being made within the following range. As a comparative example, the same method as in Example 6 was carried out, but the content of the antioxidant was 0.
Comparative heavy-duty anti-corrosion coated steel sheet pile (2) having the antioxidant content of No. 01 and comparative heavy-duty anti-corrosion coated steel sheet pile (2) having the antioxidant content of 6.0 were manufactured. Comparison of the heavy-duty anti-corrosion coated steel sheet piles obtained as above The heavy-duty anti-corrosion coated steel sheet piles were subjected to the same 3-year marine service test as in Example 6, and after the test, fluorine-based paint coating or fluororesin paint coating was applied. In addition to observing the presence or absence of blistering, an adhesion test was conducted between these colored coatings and the electron beam crosslinked low density polyethylene coating.

The test results are shown in Table 3.

As is clear from the results in Table 3, if the antioxidant content in the electron beam crosslinked polyolefin coating of the heavy corrosion protection coated steel sheet pile according to the present invention is in the range of 0.05 to 5% by weight,
Even after a year of marine practical use tests, there was no blister formation in the fluorine-based paint film, and the adhesive strength between the fluorine-based paint film and the low-density polyethylene coating was sufficiently high. However, when the antioxidant content is 0.01% by weight and 6% by weight, blisters occur in the fluorine-based paint S, and the fluorine-based paint film and electron beam crosslinked low-density polyethylene The adhesion between the coating and the coating is also reduced.

Example 8 In the same manner as in Example 6, the degree of corona discharge treatment applied to the electron beam low-density polyethylene coating was varied from 36 to 7° dyn/cm in terms of "wetting index (surface tension)", and the results were obtained according to the present invention. Heavy anti-corrosion coated steel sheet piles ■ to ■ were manufactured. As a comparative example, a comparative heavy anti-corrosion coated steel sheet pile (2) was produced using the same method as in Example 6, in which the degree of corona discharge treatment was 346 yn/cm in terms of "wetting index (surface tension)". Comparison of the heavy-duty anti-corrosion coated steel sheet piles obtained as above The heavy-duty anti-corrosion coated steel sheet piles were subjected to the same 3-year marine service test as in Example 6, and after the test, fluorine-based paint coating or fluororesin paint coating was applied. The presence or absence of blistering was observed, and an adhesion test was conducted between these colored coatings and the electron beam crosslinked low density polyethylene coating. The test results are shown in Table 3.

As is clear from the results in Table 3, if the degree of corona discharge treatment used in the present invention is 36 to 70 dyn/cm in terms of "wetting index (surface tension)", fluorine-containing There is no blistering of the paint film, and the adhesion between the fluorine-based paint film and the low-density polyethylene coating is sufficiently high.However, the "wetting index (surface tension)" is 3.
At 46 yn/cm, blisters occur in the fluorine-based paint film, and the adhesive strength between the fluorine-based paint film and the electron beam crosslinked low-density polyethylene coating also decreases.

Example 9 Using the same method as in Example 6, the present invention was carried out by changing the electron beam crosslinked low density polyethylene coated steel sheet pile to an electron beam crosslinked high density polyethylene coated steel sheet pile and an electron beam crosslinked ethylene propylene block copolymer coated steel sheet pile. Heavy-duty anti-corrosion coated steel sheet pile■
～■ was manufactured. Comparison of the heavy-duty anti-corrosion coated steel sheet piles obtained as above The heavy-duty anti-corrosion coated steel sheet piles were subjected to the same 3-year marine service test as in Example 6, and after the test, fluorine-based paint coating or fluororesin paint coating was applied. In addition to observing the presence or absence of blistering, an adhesion test was conducted between these colored coatings and the electron beam crosslinked high-density polyethylene coating and the electron beam crosslinked ethylene propylene block copolymer coating. The test results are shown in Table 3.

As is clear from the results in Table 3, the heavy corrosion-resistant coated steel sheet pile according to the present invention was subjected to a three-year marine practical use test regardless of the type of electron beam crosslinked polyolefin used in the electron beam crosslinked polyolefin coated steel sheet pile used for its manufacture. There was no blister formation of the fluorine paint film after use, and the fluorine thread paint! ! ! The adhesion between the membrane and the low density polyethylene coating is also sufficiently high.

Example 10 F S P III type steel sheet pile with a length of 5,500 mm was transferred on table rollers, and the surface of the peaks was subjected to grid blasting to remove rust and the chromate treatment agent was applied to the total chromium coating amount to 350 mg/m2. The epoxy primer was spray-painted to a film thickness of 50 μm and cured by heating, and then a maleic anhydride-modified straight-cured low-density polyethylene adhesive was laminated with electron beam cross-linked black low-density polyethylene. The sheet was attached to obtain an electron beam crosslinked low density polyethylene coated square steel sheet pile. The content of antioxidant in the electron beam crosslinked black low density polyethylene coating was 0.3% by weight, the film thickness of the electron beam crosslinked black low density polyethylene coating was 2.5 mm, and the maleic anhydride modified linear low density The film thickness of the polyethylene adhesive was 200μ. The electron beam cross-linked black low-density polyethylene coated steel sheet pile obtained as described above is transported by table rollers 5 (transport speed + 2.0 m/min) L as shown in FIG.
/ while the surface 15 of the web part of the coating is corona discharge treated with a continuously rotating first rolled electrode 16, and then the surface 17 of the flange part is treated with a continuously rotating second rolled electrode 18. After the comana-N'A treatment, a urethane primer (50% by weight of urethane prepolymer containing terminal isocyanate groups, 50% by weight of toluene) was applied to the surface, and the acrylic-silicon and acrylic-based primers shown in Table 2 were applied to the surface. Apply urethane colored paint to a thickness of 30μ,
Heavy anti-corrosion coated steel sheet piles ① to ＠ according to the present invention were manufactured. The heavy anti-corrosion coated square steel sheet pile obtained as described above was subjected to the same 3-year marine use test as in Example 6, and after the test was completed, the presence or absence of blisters in the fluorine-based paint film or fluororesin paint film was observed. At the same time, an adhesion test was conducted between these colored coatings and an electron beam crosslinked low density polyethylene coating.

The test results are shown in Table 3.

As is clear from the results in Table 3, even when acrylic-silicon-based or acrylic-urethane-based colored paints were used, there was no occurrence of blisters in the colored paint film even after three years of actual marine usage tests. Moreover, the adhesion between the colored paint film and the electron beam crosslinked low density polyethylene coating is sufficiently high.

(Effect of the invention) As is clear from the above examples, electron beam crosslinked polyolefin containing 0.05 to 5.0% by weight of an antioxidant in the outermost layer of the surface of the steel sheet pile and having the surface treated with corona discharge is used. After applying a urethane primer or a modified polyolefin primer to the surface of existing electron beam cross-linked polyolefin-coated steel sheet piles, coloring with various colors of fluorine-based paints, acrylic-silicon-based paints, acrylic-urethane-based paints, etc. The heavy-duty anti-corrosion coated steel sheet pile according to the present invention obtained by coating with paint has the following properties compared to conventional heavy-duty anti-corrosion coated steel materials:
Fluorine paints in various colors, acrylic-silicon paints,
Water-resistant adhesion between a colored paint film such as an acrylic-urethane paint and an electron beam crosslinked polyolefin coating is extremely excellent.

[Brief explanation of drawings]

Figures 1 and 7 are partial cross-sections of heavily anti-corrosion coated steel sheet piles in which the troughs of the steel sheet piles are coated with the coating of the present invention, and Figures 2 and 8 are the crests of the steel sheet piles in which the coating of the present invention is coated. FIGS. 3 and 9 are partial cross-sectional views of the heavily anti-corrosion coated steel sheet pile according to the present invention, and FIGS. 4 and 5 are cross-sectional views of the heavily anti-corrosion coated steel sheet pile according to the present invention. FIG. 6 is a partial cross-sectional view of a conventional heavy corrosion-resistant coated steel material. In the figure, 1 is a steel sheet pile or steel material, 2 is an electron beam cross-linked polyolefin treated with corona discharge, and 3 is an antioxidant in the outermost layer.
．． 05 to 5.0% by weight of electron beam cross-linked polyolefin-coated steel sheet piles, 4 is a colored paint film such as fluorine-based, acrylic-silicon-based, acrylic-urethane-based paint having various colors, 5 is a table roller, 6 is a Chromate treatment agent coating, 7 is an epoxy primer coating, 8 is a modified polyolefin adhesive, 9, 11.13 is each surface of the web part, flange part, and claw part of the steel sheet pile whose valleys are coated with electron beam crosslinked polyolefin, 15.17 is a steel sheet pile web portion whose ridges are coated with electron beam crosslinked polyolefin, each surface of the flange portion, 10, 12, 14, 16.18 are continuously rotating roll electrodes, 20 is an inorganic brimer, 21 is an organic primer, 22 is an adhesive layer, 23 is a polyolefin resin layer, 24 is a urethane primer layer, 25 is a fluororesin layer containing a colored pigment, and 26 is a urethane primer or a modified polyolefin primer layer. 4 Coatings (7) Chromate treatment agent coating 7 Epoxy primer coating 8/Modified polyolefin adhesive 26 Urethane primer or modified polyolefin in primer Procedural Amendment 1゜Indication of the case 2008 Patent No. 22771j 2゜Name of the invention Name Nippon Steel Corporation 4゜Agent address 2-6-2 Marunouchi, Chiyoda-ku, Tokyo Sub Building 3307° Target of Amendment Contents of Amendment As shown in the attached document, the following matters will be amended in the specification and drawings of the application. In Note 1, page 6, line 13, the phrase ``There is a problem of smearing.'' has been corrected to ``There is a tendency to smear, and further improvement in water-resistant adhesion is desired.'' 2. On page 12, lines 11 and 12, the phrase ``does not pose any hindrance to the present invention.'' is corrected to ``It comes.'' 3, page 19, line 2, page 23, line 15, page 32, line 15
In the first line, the words "heavy corrosion-resistant coated square steel pipe piles" are corrected to "heavy-heavy corrosion-proof coated steel sheet piles." 4. On page 19, line 7, the phrase "coated steel sheet pile 3" is corrected to "coated steel sheet pile." 5. In the 4th line of page 31, "Yaita■" is corrected to "Yaita [stock]". 6- Delete the following from lines 6 to 16 on page 31: ``As a comparison material... comparatively heavy anti-corrosion coated steel sheet pile ■ was obtained.'' 7. On page 31, lines 17 and 18, the phrase "Heavy corrosion protection plate Nw4 sheet pile ■ and comparison heavy corrosion protection coated N steel sheet pile ■" is corrected to read "Heavy corrosion protection coated steel sheet pile [phase]". 8. On page 32, lines 7 and 8, delete the text ``Compared to heavily corrosion-protected N steel sheet piles.'' 9. Delete "significantly" on page 32, line 12. 10 On page 32, line 20, "Steel sheet piles ■~■" is corrected to "Steel sheet piles [phase]~■". 11 In the second line of page 33, the text "Comparative heavy corrosion-resistant coated steel sheet pile ■" is corrected to "Comparative heavy-duty corrosion-proof coated steel sheet pile ■." 12 On page 33, line 4, "Yaita ■" is corrected to "Yaita ■." 13. On page 34, line 9, "Steel sheet piles ■~■" is corrected to "Steel sheet piles 0~O." On page 34, line 12, "Comparative heavy corrosion-resistant coated steel sheet pile ■" is corrected to "Comparative heavy-duty anti-corrosion coated steel sheet pile ■." On page 35, line 17, the words "heavy anti-corrosion coated steel sheet piles ■~■" are corrected to "heavy anti-corrosion coated steel sheet piles O~■". ] 6 On page 38, line 3, "heavy anti-corrosion coated steel sheet pile ■~0" is corrected to "heavy anti-corrosion coated steel sheet pile [phase]~G". “Table 3” on pages 41 and 42 is corrected as follows. 5 7 4 18. Correct "Figure 1", "Figure 2", "Figure 3", "Figure 6", "Figure 7", "Figure 8", and "Figure 9" in the drawings to the drawings submitted today. . Colored coating such as T4) 4 Coating No. 3 Fig. 1: Steel sheet pile 2: Corona discharge treated electron beam polyolefin 4,
Colored paint coatings such as fluorine-based, acrylic-silicon, and other paints with various colors 6; chromate treatment agent coating 7; epoxy primer coating 8: modified polyolefin adhesive acrylic-urethane White urethane primer or modified polyolefin primer Figure 9 Steel sheet pile chromate treatment agent coating Epoxy primer coating modified polyolefin adhesive @

Claims (1)

[Scope of Claims] 1 Various types of materials are applied to the surface of an electron beam crosslinked polyolefin coated steel sheet pile having an electron beam crosslinked polyolefin whose outermost layer contains 0.05 to 5.0% by weight of an antioxidant and whose surface has been subjected to corona discharge treatment. A heavy anti-corrosion coated steel sheet pile characterized by being laminated with colored paint films such as colored fluorine paints, acrylic-silicon paints, and acrylic-urethane paints. 2. An electron beam crosslinked polyolefin coated steel sheet pile, in which the valleys of the steel sheet pile are coated with an electron beam crosslinked polyolefin containing 0.05 to 5.0% by weight of an antioxidant in the outermost layer, is transferred on a table roller while the coating is removed. The surface of the web portion is subjected to a corona discharge treatment using a first rolling electrode that rotates continuously, then the surface of the flange portion is subjected to a corona discharge treatment using a second rolling electrode that is continuously rotating, and then the surface of the claw portion is treated with a corona discharge treatment using a continuously rotating second rolling electrode. A heavy-duty method characterized by applying colored paints such as fluorine-based paints, acrylic-silicon-based paints, and acrylic-urethane-based paints in various colors after the surface is treated with corona discharge using a third roll-type electrode that rotates continuously. Manufacturing method for anti-corrosion coated steel sheet piles. 3. Electron beam crosslinked polyolefin coated steel sheet piles, in which the peaks of the steel sheet piles are coated with electron beam crosslinked polyolefin containing 0.05 to 5.0% by weight of antioxidant in the outermost layer, are transferred on a table roller while the coating is removed. The surface of the web part is subjected to a corona discharge treatment using a first rolling electrode that rotates continuously, and then the surface of the flange part is subjected to a corona discharge treatment using a second rolling electrode that continuously rotates. 1. A method for manufacturing heavy anti-corrosion coated steel sheet piles, which comprises applying a colored paint such as paint, acrylic-silicon paint, acrylic-urethane paint, etc. 4. A urethane primer or a modified polyolefin primer, A heavy anti-corrosion coated steel sheet pile characterized by sequentially laminating colored paint films of various colors such as fluorine paint, acrylic-silicon paint, acrylic-urethane paint, etc. 5 Electron beam crosslinked polyolefin-coated steel sheet piles, in which the valleys of the steel sheet piles are coated with electron beam crosslinked polyolefin containing 0.05 to 5.0% by weight of an antioxidant in the outermost layer, are transferred on a table roller while the coating is removed. The surface of the web portion is subjected to a corona discharge treatment using a first rolling electrode that rotates continuously, then the surface of the flange portion is subjected to a corona discharge treatment using a second rolling electrode that is continuously rotating, and then the surface of the claw portion is treated with a corona discharge treatment using a continuously rotating second rolling electrode. After the surface is subjected to corona discharge treatment using a third rolling electrode that rotates continuously, a urethane primer or a modified polyolefin primer is applied to the surface, and fluorine-based paints of various colors,
A method for producing heavy anti-corrosion coated steel sheet piles, which comprises coating with a colored paint such as an acrylic-silicon paint or an acrylic-urethane paint. 6 Electron-beam-crosslinked polyolefin-coated steel sheet piles, in which the peaks of the steel sheet piles are coated with electron-beam crosslinked polyolefin containing 0.05 to 5.0% by weight of antioxidant in the outermost layer, are transferred on a table roller while the coating is removed. The surface of the web portion is subjected to a corona discharge treatment using a first roll-type electrode that rotates continuously, and then the surface of the flange portion is subjected to a corona discharge treatment using a second roll-type electrode that rotates continuously. Apply primer or modified polyolefin primer,
Fluorine paints in various colors, acrylic-silicon paints,
A method for producing heavy corrosion-resistant coated steel sheet piles, which comprises coating with a colored paint such as an acrylic-urethane paint.