JPH07258597A - Zinc-rich paint composition and method of coating therewith - Google Patents

Abstract

PURPOSE:To obtain a zink-rich paint composition having a short drying time, good impact resistance and excellent adhesion to especially polished steel sheet and being reduced in deterioration by sea salt particles by mixing a specified modified epoxy resin with an amic acid or a polyaminoamide and a specified zinc power. CONSTITUTION:This composition is prepared by mixing a polysulfide-modified epoxy resin represented by the formula (where R1 and R3 are each and organic group having a bisphenol skeleton; and R2 is an organic group having a polysulfide bond) and having an everage molecular weight of 1000 or above (e.g. FVD-123X, a product of Toray Thiokol, Co.,Ltd.) with an amine or a polyaminoamide (e.g. Sanmide 390-70X, a product of Sanwa Kagaku Kogyo K.K.) in an amount of desirably 0.3-200 pts.wt. per 100 pts.wt. modified epoxy resin and a zinc powder of a mean particle diameter of 20mum or below in an amount 500 pts.wt. or above per 100 pts.wt. modified epoxy resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zinc-rich paint composition, and more specifically, it has a short drying time, good impact resistance, and various adherends such as iron plates and hot dip galvanized plates The present invention relates to a zinc-rich paint composition that has good adhesion to a steel plate and has very little deterioration due to sea salt particles.

[0002]

2. Description of the Related Art In recent years,
Various projects have progressed due to the development of the so-called waterfront, and development of piers, international conference halls, maintenance of marinas, construction of sea berths, sea bridges, sea airports, etc. have been actively carried out. Such an offshore structure, or
For ships, bridges, large plants, coastal structures, marine containers, inside and outside water pipes, etc., long-term heavy corrosion protection is required. A paint system using a resin-based zinc rich paint is typical. However, the conventional bisphenol-type epoxy resin-based zinc rich paint is poor in flexibility and has a small cohesive force of the coating film, so that peeling from the material and cracking of the coating film are likely to occur, and they are easily broken by impact.

Zinc rich paints are often used as base coats, with medium and top coats usually being applied over the zinc rich paint. One of the reasons for this is that zinc dust is easily affected by sea salt particles and sea water, and zinc is easily consumed. The heavy-duty anticorrosion paint system expects anticorrosion properties for the middle and top coats, but if the zinc-rich paint for the undercoat alone is more anticorrosive than the conventional bisphenol epoxy resin-based zinc-rich paint, The anticorrosion property of the entire heavy-duty anticorrosion paint system in which the middle coat and the top coat are applied on the rich paint is further improved.

Further, for example, when constructing a large steel structure such as a ship, first, a black rust on the surface of a steel material formed by rolling a high-temperature steel material, so-called black skin, is removed by sandblasting or the like, and then a shop primer is applied. Apply. afterwards,
The steel plate is cut, blocks are assembled, and welded to assemble the hull. At this time, since the welded portion is polished by a disc sander or the like, the shop primer applied first is completely removed, and the welded portion becomes smooth by polishing. As described above, the adhesion to the polished steel plate is important, but the usual zinc-rich paint has poor adhesion to the steel plate that is smoothed by polishing, which may cause trouble. It was

In order to solve these problems, JP-A-3-
81374 is a polysulfide-modified epoxy resin,
Disclosed is a coating formulation containing amines or polyaminoamides and zinc dust. However, the adhesion of this coating composition to the ground steel plate is not sufficient, and the workability, adhesion, anticorrosiveness, etc. are also insufficient.

Therefore, an object of the present invention is that the drying time is short, the impact resistance is good, and the adhesion to various adherends such as an iron plate and a hot dip galvanized plate, especially to a polished steel plate is good. Another object of the present invention is to provide a zinc rich paint composition that is extremely less deteriorated by sea salt particles. Another object of the present invention is to provide a method for applying a zinc rich paint composition onto a polished steel plate.

[0007]

As a result of earnest research in view of the above object, the present inventors have found that (a) a polysulfide-modified epoxy resin having a specific structure, (b) an amine or polyaminoamide, c) A zinc rich paint composition containing a specific amount of zinc dust having an average particle size of 20 μm or less has a short drying time, good impact resistance, and various adherends such as an iron plate and a hot dip galvanized plate, particularly The inventors have found that the adhesiveness to the ground steel plate is good and that the deterioration due to sea salt particles is extremely small, and the present invention has been made.

That is, the zinc rich paint composition of the present invention comprises (a) the general formula:

[Chemical 3] (However, R ₁ and R ₃ are organic groups having a bisphenol skeleton, and R ₂ is an organic group having a polysulfide bond.), And a polysulfide-modified epoxy resin having an average molecular weight of 1000 or more, (B)
Amines or polyaminoamides, and (c) 5 per 100 parts by weight of the polysulfide-modified epoxy resin.
It is characterized by containing at least 100 parts by weight of zinc powder having an average particle size of 20 μm or less.

Further, the coating method of the present invention comprises (a) a general formula

[Chemical 4] (However, R ₁ and R ₃ are organic groups having a bisphenol skeleton, and R ₂ is an organic group having a polysulfide bond.), And a polysulfide-modified epoxy resin having an average molecular weight of 1000 or more, (B)
Amines or polyaminoamides, and (c) 5 per 100 parts by weight of the polysulfide-modified epoxy resin.
A zinc rich paint composition containing at least 100 parts by weight of zinc powder having an average particle size of 20 μm or less is directly applied onto a steel plate.

The present invention is described in detail below. [1] Polysulfide-modified epoxy resin The (a) polysulfide-modified epoxy resin used in the present invention is represented by the following general formula (1).

[Chemical 5] In the above general formula (1), R ₁ and R ₃ are organic groups containing a bisphenol skeleton, and R ₂ is an organic group containing a polysulfide bond.

Examples of the organic groups R ₁ and R ₃ containing the bisphenol skeleton include bisphenol A type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, halogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin. resin,
Examples thereof include those having a molecular structure equivalent to that of halogenated bisphenol F type epoxy resin, or those containing a similar molecular structure.

The organic group R ₂ containing a polysulfide bond in the general formula (1) is represented by the following general formula (2).

[Chemical 6]

In the above general formula (2), the range of the average content m of S is preferably 1 to 3, and particularly preferably 1.5 to 2.5. Further, the range of the average content n of the polysulfide skeleton is preferably 1 to 50, particularly preferably 2 to 30. When the average content n of the polysulfide skeleton is less than 1, it becomes equivalent to that of a normal bisphenol type epoxy resin, and when n exceeds 50, the viscosity becomes high and it becomes difficult to use.

Further, R ₄ in the above general formula (2) is preferably an organic group containing two or more carbon atoms, and particularly preferably one represented by the following general formula (3) or (4). .

[Chemical 7]

[Chemical 8]

The polysulfide-modified epoxy resin as described above has an average molecular weight of 1000 or more, preferably 12
00 or more, more preferably 1300 to 10,000
Is. If the average molecular weight is less than 1000, the drying time at room temperature tends to be delayed. Examples of such polysulfide-modified epoxy resin include "FLEP-410XA" and "FLEP-1" manufactured by Toray Thiokol Co., Ltd.
20X "," FVD-105X "," FVD-125 "
X ”,“ FVD-423XA ”and the like.

In the present invention, it is desirable to use the polysulfide-modified epoxy resin alone, but it is also possible to mix the polysulfide-modified epoxy resin with a small amount of a bisphenol type epoxy resin, if necessary.

[2] Amines or polyaminoamides Examples of amines used in the present invention include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, isophoronediamine, and 1,3-bis (amino). Methyl) cyclohexane, m-xylenediamine, cyclohexylamine,
N-cyanoethylxylylenediamine, N-aminoethylpiperazine, 1- (2-aminoethyl) piperazine,
N-cyanoethylxylylenediamine, menthenediamine, N-benzylethylenediamine, bis (4-amino-3-methylcyclohexyl) methane, m-phenylenediamine, polyamine epoxy resin produced by reacting epoxy resin with excess amine Adducts, polyamine-ethylene oxide adducts, polyamine-propylene oxide adducts, cyanoethylated polyamines, or dehydration condensation products obtained by reacting polyamines with phenols and aldehydes, modified polyamines (for example, manufactured by Asahi Denka Kogyo KK) "Adeka Hardener E
H-220 "," ADEKA HARDNER EH-221 ",
"ADEKA HARDNER EH-227", "ADEKA HARDNER EH-230", "ADEKA HARDNER EH257-1"
7 "," ADEKA HARDNER EH-303B "," ADEKA HARDNER EH-531 "and" ADEKA HARDNER EH
-752D "," ANKAI MCA "manufactured by ACI Japan Limited," Araldide X1101 "manufactured by Ciba-Gaiki Co., Ltd.," Epicure 3012 "," Epicure 32 "manufactured by Yuka Shell Epoxy Co., Ltd.
55 "," Epicure XD-358 "," Epomate B "
-002W "," Epomate N-001 "," Epomate QX-2 "and" Epomate RX-3 "," Sumicure AF "manufactured by Sumitomo Chemical Co., Ltd.," Epomic Q manufactured by Mitsui Petrochemical Co., Ltd. " -611 ", Daito Sangyo Co., Ltd.
"Daitokuraru HD-438", "Daitokuraru HD-801CB", "Daitokuraru HD-Q",
"Daitokural I-1199", "Daitokuraru J
-1666 "," Daito Clar SK-900FC
B "," Daitokural X-973 "," Daitokural X-1301S "," Daitokural X-132 "
1 "," Daitoclar X-1777A "," Daitoclar X-1840 "," Daitoclar X-194 "
2 "," Daitoclaar X-2392 "and" Daitoclaar X2733 "," Lackhamide WH-036-S "manufactured by Dainippon Ink and Chemicals," Fujicure 5001 "," Fujicure "manufactured by Fuji Kasei Co., Ltd. 542
0 "and" Fujicure E-1604 "," Sanmide E-1001 "and" Sunmide W-3000 "manufactured by Sanwa Chemical Industry Co., Ltd., and" React CA-101 "and" React "manufactured by Sanyo Chemical Industry Co., Ltd. CA-681 "and the like).

The polyaminoamides used in the present invention are polymers having a plurality of amino groups and one or more amide groups. Specifically, for example, "Adeka Hardener EH-" manufactured by Asahi Denka Co., Ltd. 203 "and" ADEKA HARDNER EH-204 "," TOMIDE 225-ND "and" TOMIDE 245 "manufactured by Fuji Chemical Industry Co., Ltd.,
"Sunmide 150-6" manufactured by Sanwa Chemical Industry Co., Ltd.
5 "," Sunmide 305-70X "," Sunmide # 351-55 "," Sunmide 390-70 "and the like.

The compounding amount of amines or polyaminoamides varies depending on their kind, but is usually 0.3 to 100 parts by weight of polysulfide-modified epoxy resin.
The amount is 200 parts by weight, preferably 1 to 100 parts by weight.

[3] Zinc Powder The zinc powder used in the present invention has an average particle size of 20 μm or less, preferably 10 μm or less. In particular, the proportion of particles having a particle size of 75 μm or more is 10%.
The following zinc dust is preferable, and zinc dust in which the proportion of particles having a particle size of 75 μm or more is 5% or less is more preferable. Further, the metallic zinc component in the zinc powder is preferably 75% or more, and 90%
The above is more preferable.

The zinc powder content in the present invention is 50 based on 100 parts by weight of the polysulfide-modified epoxy resin.
It is 0 part by weight or more, preferably 600 parts by weight or more, and more preferably 600 to 3000 parts by weight.

[4] Other Components The anticorrosion coating composition aimed at by the present invention is mainly composed of a polysulfide-modified epoxy resin, amines or polyaminoamides, and zinc dust. Toluene, xylene, methyl acetate, ethyl acetate, acetone, butyl acetate, propyl acetate, pentyl acetate, tetrahydrofuran, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, cyclohexanone, butyl cellosolve, methyl cellosolve, ethyl cellosolve, methanol, ethanol, propanol,
Butanol, methylene chloride, chloroform, styrene monomer, dioctyl phthalate, dibutyl phthalate,
Organic solvent such as hydrogenated castor oil, phenyl glycidyl ether, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, cresyl glycidyl ether, polyethylene glycol glycidyl ether, polypropylene glycol glycidyl ether, 1,6-hexanediol diglycidyl ether, non-solvent A compatible or compatible substance such as a reactive diluent or a reactive diluent can be added. In addition, these organic solvents,
You may use only 1 type and may mix and use 2 or more types.

In the zinc-rich coating composition of the present invention, if necessary, yellow lead, red lead, zinc white, ocher,
Calcium leadate, cyanamide lead, kaolin, clay, ultramarine, chromium oxide, titanium oxide, silica, aluminum hydroxide, iron oxide, lead suboxide, quartz powder, talc, calcium carbonate, barium sulfate, lead chromate, zinc chromate,
Pigments such as organic bentonite, dispersants, fillers, thickeners, extenders, anti-sagging agents, reinforcing materials and the like can be added.

[5] Coating Method In the coating method of the present invention, the above-mentioned zinc rich paint composition is directly coated on the steel plate. The surface of the steel plate may or may not be polished in advance.

Generally, the surface condition of the steel sheet affects the adhesion of the coating. When the surface of the steel plate is polished by sandblasting, sandpaper, or the like, not only rust is removed, but also the surface becomes uneven, and the surface roughness, that is, the surface area of the steel plate becomes large and the adhesion becomes large. However, if the surface of the steel plate is further polished, on the contrary, the surface becomes smooth and the surface roughness, that is, the surface area of the steel plate, tends to be small, and the adhesion tends to be weak. The zinc-rich paint composition used in the coating method of the present invention has good adhesion to a metal surface, particularly a steel plate surface, due to the effect of a polysulfide-modified epoxy resin, and can be applied even on a smooth surface. Regardless of your choice, process management becomes easier.

In the coating method of the present invention, the surface roughness of the steel plate is shown in JIS B 0659 (1978) "Comparative surface roughness standard piece". Coating is possible even when there is some unevenness such as SN 10 to 12, and coating is possible even when it is smooth as SN 8 or less. Preferable surface roughness of the steel plate in the coating method of the present invention is practically SN.
It is 6 or more.

[0027]

As described above, the zinc-rich paint composition of the present invention comprises (a) a polysulfide-modified epoxy resin having an average molecular weight of 1000 or more, (b) an amine or polyaminoamide, and (c) an average particle size. It contains 500 parts by weight or more of zinc powder having a diameter of 20 μm or less.

Accordingly, the polysulfide-modified epoxy resin has good chemical resistance, impact resistance, adhesion to various adherends such as an iron plate and a hot-dip galvanized plate, especially to a polished steel plate, and high water vapor. Has a blocking property. Further, due to the effects of both the polysulfide-modified epoxy resin and zinc dust, the zinc-rich paint composition has very little deterioration due to sea salt particles and has good corrosion resistance.

As described above, the zinc-rich paint composition of the present invention and the coating method using the same are
It is particularly effective in fields that require long-term heavy corrosion protection, such as bridges, large plants, coastal structures, marine containers, and water pipes.

[0030]

The present invention will be described in more detail by the following examples. Example 1 Polysulfide-modified epoxy resin having an average molecular weight of about 2000 dissolved in xylene (“F” manufactured by Toray Thiokol Co., Ltd.)
VD-123X ") 100 parts by weight (in terms of solid content), 40 parts by weight of polyaminoamide (" Sanmide 390-70X "manufactured by Sanwa Chemical Industry Co., Ltd.) as a curing agent, and zinc powder having an average particle diameter of 5 to 10 m. 1030 parts by weight are mixed, 30 parts by weight of talc as an inorganic filler, 200 parts by weight of xylene as a solvent, and 55 parts of methyl isobutyl ketone.
By weight, 30 parts by weight of 1-butanol were mixed to prepare a zinc rich paint composition. The zinc rich paint composition was evaluated for its adhesion to steel plate and outdoor corrosion resistance after outdoor exposure. The measurement results are shown in Table 1 together with the composition of the composition.

Example 2 Polysulfide-modified epoxy resin having an average molecular weight of about 2400 dissolved in a mixed solvent of xylene and 1-butanol ("FLEP-410XA" manufactured by Toray Thiokol Co., Ltd.)
100 parts by weight (in terms of solid content) of polyaminoamide as a curing agent (“SANMIDE 390” manufactured by Sanwa Chemical Industry Co., Ltd.)
-70X ") 22 parts by weight, 1030 parts by weight of zinc powder having an average particle size of 5 to 10 µm, 30 parts by weight of talc, 175 parts by weight of xylene as a solvent, and methyl isobutyl ketone 5
Mixing 0 parts by weight and 25 parts by weight of 1-butanol,
It was a zinc rich paint composition. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 1 together with the composition of the composition.

Example 3 Polysulfide-modified epoxy resin (“FVD-423XA” manufactured by Toray Thiokol Co., Ltd.) having an average molecular weight of about 3000 dissolved in a mixed solvent of xylene and 1-butanol 1
00 parts by weight (in terms of solid content) and polyaminoamide as a curing agent (“SANMIDE 390-” manufactured by Sanwa Chemical Industry Co., Ltd.).
70X ") 15 parts by weight, 1030 parts by weight of zinc powder having an average particle size of 5 to 10 µm, 30 parts by weight of talc, 155 parts by weight of xylene as a solvent, and methyl isobutyl ketone 4
5 parts by weight and 20 parts by weight of 1-butanol are mixed,
It was a zinc rich paint composition. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 1 together with the composition of the composition.

Comparative Example 1 100 parts by weight of bisphenol epoxy resin (“Epicoat 1001” manufactured by Yuka Shell Epoxy Co., Ltd.) having an average molecular weight of about 1000 dissolved in xylene (as solid content) was used as a curing agent for polyaminoamide (Sanwa). 56 parts by weight of "Sanmide # 390-70X" manufactured by Kagaku Kogyo Co., Ltd., 1030 parts by weight of zinc powder having an average particle size of 5 to 10 μm, 30 parts by weight of talc, 190 parts by weight of xylene as a solvent, and methyl isobutyl ketone. 55 parts by weight and 1-butanol 2
5 parts by weight were mixed to obtain a zinc rich paint composition. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 1 together with the composition of the composition.

Measurement of Adhesion to Steel Sheet After Outdoor Exposure (1) In order to evaluate the adhesion of the zinc rich paint composition of each of the above Examples and Comparative Examples to the steel sheet after outdoor exposure, JI
Steel plate with surface roughness indicated by SN8 based on S B 0659 standard (length 200 mm, width 100 mm, thickness 0.6 mm)
The zinc rich paint composition was applied to a dry film thickness of 40 μm and dried at room temperature for 7 days.

This test piece was exposed outdoors to a coastal industrial area (Ichihara City, Chiba Prefecture, Chikusa Coast) for one month in the summer. In addition, 5m from the coast for the purpose of making it particularly susceptible to sea salt particles.
The exposure test was conducted at the following location. After outdoor exposure, make a cut in the test piece to create 25 squares of 2 mm x 2 mm size, and add 18 m width made by Nichiban Co., Ltd. on it.
The cellophane tape of m was adhered and peeled off at a stretch, and the remaining squares were counted to evaluate the adhesion after outdoor exposure.

Table 1 Example 1 Example 2 Example 3 Comparative Example 1 Composition (parts by weight) Polysulfide-modified epoxy resin FVD-123X (solid content conversion) 100 --- FLEP-410XA (solid content conversion) -100- -FVD-423XA (solid content conversion)-100- Bisphenol type epoxy resin Epicoat 1001 (solid content conversion) ---- 100 Curing agent Sunmide 390-70X40 22 15 56 Zinc powder 1030 1030 1030 1030 Talc 30 30 30 30 30 Solvent Xylene 200 175 155 195 Methyl isobutyl ketone 55 50 45 45 55 1-Butanol 30 25 20 25 Performance Measurement of adhesion to steel plate after outdoor exposure (1) 25/25 ¹⁾ 25/25 ¹⁾ 25/25 ¹⁾ 3/25 ^{2 )} Note: 1) The coating film remained completely adhered to the steel plate. 2) The coating film peeled almost completely from the steel plate.

As is clear from Table 1, the zinc-rich paint composition of the present invention can be applied to the steel plate with a smooth surface even after the outdoor exposure within 5 m from the coast where the sea salt particles are susceptible. It adheres well. On the other hand, in the zinc rich paint composition of Comparative Example 1, the coating film peeled off from the steel plate.

Example 4 Polysulfide modified epoxy resin having an average molecular weight of about 1900 dissolved in xylene (“F” manufactured by Toray Thiokol Co., Ltd.)
LEP-120X ") 100 parts by weight (solid content conversion),
29 parts by weight of polyaminoamide (“SANMIDE 390-70X” manufactured by Sanwa Chemical Industry Co., Ltd.) as a curing agent, 925 parts by weight of zinc powder having an average particle diameter of 5 to 10 μm, and talc 50
By weight, 300 parts by weight of methyl ethyl ketone were mixed to prepare a zinc rich paint composition. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 2 together with the composition of the composition.

Example 5 Polysulfide-modified epoxy resin having an average molecular weight of about 1900 dissolved in xylene (“F” manufactured by Toray Thiokol Co., Ltd.)
LEP-120X ") 100 parts by weight (solid content conversion),
10 parts by weight of modified amine ("Fujicure 5001" manufactured by Fuji Kasei Kogyo Co., Ltd.) as a curing agent, and an average particle size of 5 to 10
A zinc-rich paint composition was prepared by mixing 925 parts by weight of zinc powder having a particle size of μm, 50 parts by weight of talc, and 300 parts by weight of methyl ethyl ketone. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 2 together with the composition of the composition.

Example 6 Polysulfide-modified epoxy resin having an average molecular weight of about 2900 dissolved in xylene (“F” manufactured by Toray Thiokol Co., Ltd.)
VD-105X ") 100 parts by weight (in terms of solid content), 15 parts by weight of polyaminoamide (" SANMIDE 390-70X "manufactured by Sanwa Chemical Industry Co., Ltd.) as a curing agent, and zinc powder having an average particle diameter of 5 to 10 m. 925 parts by weight and talc 5
A zinc rich paint composition was prepared by mixing 0 part by weight and 300 parts by weight of methyl ethyl ketone. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 2 together with the composition of the composition.

Example 7 Polysulfide-modified epoxy resin having an average molecular weight of about 2900 dissolved in xylene (“F” manufactured by Toray Thiokol Co., Ltd.)
VD-105X ") 100 parts by weight (in terms of solid content), 5 parts by weight of a modified amine (" Fujicure 5001 "manufactured by Fuji Kasei Kogyo Co., Ltd.) as a curing agent, and an average particle diameter of 5 to 10 m.
925 parts by weight of zinc powder, 50 parts by weight of talc, and 300 parts by weight of methyl ethyl ketone were mixed to obtain a zinc rich paint composition. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 2 together with the composition of the composition.

Comparative Example 2 100 parts by weight of bisphenol epoxy resin (“Epicoat 1001” manufactured by Yuka Shell Epoxy Co., Ltd.) having an average molecular weight of about 1000 dissolved in xylene (as solid content) and polyaminoamide (Sanwa) as a curing agent. 40 parts by weight of "Sunmide 390-70X" manufactured by Kagaku Kogyo Co., Ltd., 925 parts by weight of zinc powder having an average particle diameter of 5 to 10 μm, and talc 5
A zinc rich paint composition was prepared by mixing 0 part by weight and 300 parts by weight of methyl ethyl ketone. The adhesiveness of this zinc rich paint composition to a steel plate after outdoor exposure was evaluated. The measurement results are shown in Table 2 together with the composition of the composition.

Measurement of Adhesion to Steel Sheet after Outdoor Exposure (2) In order to evaluate the adhesion of the zinc rich paint composition of each of the above Examples and Comparative Examples to the steel sheet after outdoor exposure, JI
A zinc rich paint composition is dried to a thickness of 60 μm on a steel plate having a surface roughness indicated by SN8 based on S B 0659 standard and having a length of 200 mm, a width of 100 mm and a thickness of 0.6 mm.
And then dried at room temperature for 7 days. This test piece is placed in the coastal industrial zone (Ichihara City, Chiba Prefecture, Chikusa Coast) 1
For 0 months, it was exposed outdoors about 100 m from the coast.

After outdoor exposure, the test piece was cut into a size of 2 mm × 2 mm to form 25 squares, and a cellophane tape of 18 mm width made by Nichiban Co., Ltd. was adhered to it to make a sudden stroke. The adhesion after outdoor exposure was evaluated by peeling and counting the remaining squares.

Table 2 Example 4 Example 5 Example 6 Composition (parts by weight) Polysulfide-modified epoxy resin FLEP-120X (solid content conversion) 100 100-FVD-105X (solid content conversion) --100 Curing agent Sunmide 390 -70X 29-15 Fujicure 5001-10- Zinc dust 925 925 925 Talc 50 50 50 Solvent Methyl ethyl ketone 300 300 300 Performance Measurement of adhesion to steel plate after outdoor exposure (2) 24/25 ³⁾ 24/25 ³⁾ 25/25 ⁴⁾ Note: 3) The coating film remained almost completely adhered to the steel plate. 4) The coating film remained completely adhered to the steel plate.

Table 2 (continued) Example 7 Comparative Example 2 Composition (parts by weight) Polysulfide modified epoxy resin FVD-105X (solid content conversion) 100- Bisphenol type epoxy resin Epicoat 1001 (solid content conversion) -100 Curing agent Sunmide 390-70X-40 Fujicure 50015 5- Zinc dust 925 925 Talc 50 50 Solvent Methyl ethyl ketone 300 300 Performance Measurement of adhesion to steel plate after outdoor exposure (2) 25/25 ⁴⁾ 0/25 ^{5 )} Note: 4) The coating film remained completely adhered to the steel plate. 5) The coating film was completely peeled off from the steel plate.

As is clear from Table 2, the zinc rich paint composition of the present invention has excellent adhesion because the coating film adheres well to the steel plate even when exposed outdoors on the coast. On the other hand, in the zinc rich paint composition of Comparative Example,
The coating film was completely peeled off from the steel plate.

[0048]

As described in detail above, since the zinc rich paint composition of the present invention contains a polysulfide-modified epoxy resin as a main component, it has chemical resistance, impact resistance, adhesion, corrosion resistance, and flexibility. It has excellent toughness and durability, and particularly has excellent adhesion to a polished steel plate. In addition, the zinc-rich paint composition of the present invention has a short drying time and good compatibility with the topcoat, and thus is easy to work.

Further, the zinc-rich paint composition of the present invention is a coating film having excellent anticorrosion property, which is hardly deteriorated by sea salt particles due to the effects of both the polysulfide-modified epoxy resin and the zinc powder. In addition, when the intermediate- and top-coat paints are applied on the zinc-rich paint composition for the night and night, the anticorrosion property of the entire heavy anticorrosion paint system is further improved.

Since the coating method of the present invention has good adhesion to the ground steel plate, the coating process is easy to manage and troubles can be prevented.

As described above, the zinc-rich paint composition and the coating method of the present invention are applied to fields requiring long-term heavy corrosion protection, for example, bridges, railways, large plants, containers, buildings, water pipes, automobiles. It is suitable for application to ships, marine structures, and structures on the coast to improve the corrosion resistance.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area C09D 5/10 PQG

Claims (4)

[Claims] 1. (a) General formula: (However, R ₁ and R ₃ are organic groups having a bisphenol skeleton, and R ₂ is an organic group having a polysulfide bond.), And a polysulfide-modified epoxy resin having an average molecular weight of 1000 or more, (B)
Amines or polyaminoamides, and (c) 5 per 100 parts by weight of the polysulfide-modified epoxy resin.
A zinc-rich paint composition, which contains at least 100 parts by weight of zinc dust having an average particle size of 20 μm or less. 2. (a) General formula: (However, R ₁ and R ₃ are organic groups having a bisphenol skeleton, and R ₂ is an organic group having a polysulfide bond.), And a polysulfide-modified epoxy resin having an average molecular weight of 1000 or more, (B)
Amines or polyaminoamides, and (c) 5 per 100 parts by weight of the polysulfide-modified epoxy resin.
A coating method characterized in that a zinc rich paint composition containing at least 100 parts by weight of zinc dust having an average particle size of 20 µm or less is directly applied onto a steel plate. 3. The coating method according to claim 2, wherein the steel plate is polished. 4. The coating method according to claim 3, wherein the surface roughness of the polished steel plate is JIS B 065.
9. A coating method characterized by having an SN of 6 or more shown by 9.