JPS5815570A - Paint composition for power transmission iron tower - Google Patents

Abstract

PURPOSE:To obtain a paint composition for a power transmission iron tower plated with zinc, which paint composition is excellent in the adherence and non- slip characteristics, by making up the composition of an epoxy resin composition, an oxyacid salt or a metal oxide, and a flaky pigment or aggregate. CONSTITUTION:The titled composition consists of 100pts.wt. epoxy resin composition (e.g., a linear or branched bisphenol type epoxy resin) (A) containing two or more epoxy groups at the terminas and one or more hydroxyl groups in the side chain, 1-250pts.wt. compound (B) selected from an oxyacid salt (e.g. zinc phosphate, lead chromate) and a metal oxide (e.g. chrominum trioxide) and 10-500pts.wt. constituent (C) selected from a flaky pigment (e.g. flaky iron oxide, flaky aluminum powder, mica) and an aggregate (e.g. sand, silica sand). If 10-200pts.wt. metal zinc powder and/or calcium plumbate are further added, the long-term adhesion of its coating can further be stabilized and prolonged.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a coating composition for preventing corrosion, coloring, and sliding IF on the surfaces of so-called galvanized steel towers, such as power transmission towers and microwave towers, which are coated with galvanized steel, particularly hot-dip galvanized coatings. Pertaining to things.

Conventionally, galvanizing has been applied as a long-term corrosion protection method for steel materials and steel products, and it is well known that hot-dip galvanizing is used especially for large structures such as power transmission towers and microwave towers. It is like that.

This corrosion prevention method is far superior to general paint coating methods, but as air and water pollution has progressed recently, zinc has been depleted significantly and the long-term corrosion prevention effect is no longer as good as before. The current situation is that we cannot hope for anything. In order to make the long-term corrosion protection inherent in galvanizing effective, an organic coating film must be present on the galvanized surface to prevent water and
It has become necessary to prevent contact with corrosive factors such as the atmosphere, and as structures have become larger in recent years, it has become necessary to color and decorate structures as necessary as aviation signs or from the aesthetic point of view of environmental harmony. There is a strong need for this.

For the above-mentioned reasons, oil-based paints or synthetic resin-based paints are currently applied to galvanized surfaces.

However, this type of paint has the disadvantage that the paint film peels off and separates from the surface of the galvanized layer at an early stage, and is not always satisfactory. Furthermore, as structures become larger, repainting for maintenance becomes difficult, so tar epoxy resin paints, tar urethane resin paints, unsaturated polyester resin paints, or epoxy The use of synthetic resin paints such as resin enamel and polyurethane resin enamel is being considered.

However, all of these had poor adhesion.

On the other hand, it is common for people to go up and down power transmission towers for maintenance and inspection purposes, but because the paint films obtained from conventional paint compositions are smooth, they can be easily slippery (and dangerous) when going up and down. There was a problem.

The present invention aims to eliminate or improve the drawbacks of conventional paints as described above, and seeks to provide a paint composition that has excellent adhesion to galvanized power transmission towers and has excellent anti-slip properties. It is something to do.

That is, the present invention provides: (1) (a) An epoxy resin composition containing a small number (both two or more epoxy groups) at the terminal and at least one or more hydroxyl group in the side chain. ...100 parts by weight (b) At least one compound selected from oxyacid salts and metal oxides ...1 to 250 parts by weight, and (C) Oblate pigments and aggregates At least one selected ingredient・・・・・・・・・・・・ 10～
A coating composition for power transmission towers comprising 500 parts by weight, and (
2) (a) Epoxy resin composition containing at least two or more epoxy groups at the terminal end and at least one or more hydroxyl group at the side chain: 100 parts by weight ( b) Metallic zinc powder and/or calcium leadate
・・・・・・・・・・・・・・・10-200 parts by weight re
) At least one type of compound selected from Okipart oxygen acid salts and metal oxides...1 to 150 parts by weight,
and (mountain) at least one selected from flat pigments and aggregates.
The present invention relates to a coating composition for power transmission towers comprising 10 to 150 parts by weight of seed components.

The epoxy resin composition used in the present invention consists of a mixture of an epoxy resin containing at least two epoxy groups at the end and at least one hydroxyl group in the molecule, and a crosslinking agent. Examples of the epoxy resins include linear bisphenol type epoxy resins, methyl-substituted bisphenol type epoxy resins, and side chain bisphenol type Ebo-shi resin. Commercially available product names include, for example, Epikote Shell Chemical @) Cleavage product name],
Typical examples include Epicron and Dainippon Ingo Kagaku Kogyo @) Split Product Name] and Araldite and Ciba Geigy @) Split Product Name. These ponds can be used alone, or two or more can be used in combination to bring out the characteristics of each.

As the crosslinking agent of the present invention, any crosslinking agent that has a group that reacts with the epoxy group or hydroxyl group contained in the epoxy resin molecule and is generally used as a crosslinking agent for epoxy resins may be used. For example, aliphatic or aromatic polyamines such as diethylenetriamine, triethylenetetramine, metaxylylenediamine, metaphenylenediamine, heterocyclic diamine, secondary or tertiary polyamines such as dimethylaminomethylphenol, tris(dimethylaminomethyl)phenol, piperidine, etc. Amino compounds such as amines, polyamide resins, amine adducts (generally called amine adducts), isocyanate compounds such as tolylene diisocyanate and hexamethylene diisocyanate, as well as phenolic resins, acid anhydrides, melamine resins, urea resins, etc. Can be mentioned. Since the object of the present invention is a large structure such as a power transmission tower, the chemical reaction between the epoxy resin and the crosslinking agent proceeds at room temperature or forced drying.
Most preferred are amino compounds that undergo a chemical reaction with an epoxy group.

As will be described later, the feature of the present invention is that a small amount of the oxyacid salt and metal oxide contained in the composition chemically reacts with the galvanized surface and improves the adhesion of the coating film. In particular, when phosphate is used as an essential component and is used in combination with at least one component selected from other oxyacids and metal oxides, This is preferable because a chelate bond is formed between phosphoric acid and the hydroxyl group in the epoxy resin, giving the effect of imparting strong adhesion.Therefore, when mixing the epoxy resin and crosslinking agent of the present invention, the crosslinking agent If it is of a nature that involves a chemical reaction with hydroxyl groups in the epoxy resin molecule,
It is preferable to adjust the amount of the crosslinking agent to the epoxy resin to about 0.9 to 0.5 equivalents per equivalent of the epoxy resin, so that some of the hydroxyl groups in the epoxy resin molecules remain.

The oxyacid salts used in the present invention include chloroacid, phosphoric acid (including condensed phosphoric acid), boric acid, molybdic acid, phosphomolybdic acid, silicomolybdic acid, tungstic acid, phosphotungstic acid, silicotungstic acid, etc. It is a salt consisting of an oxygen acid and various metals.

For example, strontium chromate, calcium chromate, lead chromate, zinc chromate, zinc chromate, zinc molybdate, calcium molybdate, zinc tungstate, calcium tungstate, magnesium tungstate, zinc phosphate, lead orthophosphate, lead pyrophosphate, Lead metaphosphate, aluminum phosphate, orthophosphate, pyrophosphate, oxyphosphate, zinc tetraborate,
Zinc metaborate, lead metaborate, lead tetraborate, barium metaborate, etc. can be used.

The metal oxides used in the present invention are oxides of chromium, molybdenum, tungsten, manganese, etc.

For example, chromium trioxide, molybdenum trioxide, tungsten dioxide, manganese dioxide, etc. can be used. These oxyacid salts and metal oxides described above can be used alone or in a mixture in any proportion. In particular, when the above-mentioned phosphate is used as an essential component and is used in combination with at least one component selected from other oxyacids or metal oxides other than the phosphate, the phosphoric acid produced by its hydrolysis becomes an oxyacid or metal oxide. Since it is thought that a chelate compound is formed between the metal ion in the metal oxide and the hydroxyl group in the epoxy resin, it is most preferable to use that combination.

The amounts of the oxyacid salts and metal oxides used in the present invention vary depending on their reactivity to the grease powder-plated surface, corrosion resistance, etc., and vary accordingly, but 100 parts by weight of the epoxy resin Use the following amounts for:

That is, when metal zinc powder and/or calcium leadate, which will be described later, are used together, the amount is 1 to 150 parts by weight, preferably 5 to 100 parts by weight, based on 100 parts by weight of the epoxy resin composition. When using only at least one compound selected from metal oxides, 1 to 250 parts by weight per 100 parts by weight of the epoxy resin composition;
Preferably, it is used in a range of 10 to 120 weight; 11;

If the amount of the decoy, oxyacid salt, or gold member oxide is less than 1 part by weight within the above range, no effect of forming a chemical conversion film or forming a chelate on the galvanized surface can be expected. On the other hand, if more than 150 or 250 parts by weight of the oxyacid or metal oxide is used, the adhesion of the coating film to the galvanized surface tends to be impaired.

In the present invention, phosphate is an essential component, and other oxyacid salts and metal oxides are used.

As mentioned above, it is most effective to use it in combination with at least one selected component,
In this case, the preferred mixing ratio of the phosphate and the other oxylate and metal oxide is 95 to 30 parts by weight for the former.
The latter is 5 to 70% by weight.

The flat pigment and aggregate used in the present invention include, for example, flat iron oxide (Mi caceous IronO).
xide), flat aluminum powder, mica, glass 7 luke, mica, flat pigments such as flat lead powder, sand, gravel, silica sand,
Examples include what is generally called aggregate, such as Emme IJ- and glass peas.

These can be used alone or in combination of two or more.

The flat pigment and aggregate impart appropriate roughness to the surface of the coating layer and enhance the anti-slip effect.

At least one component selected from the flat pigment and aggregate is used in an amount of 10 to 500 parts by weight, preferably 50 to 300 parts by weight, based on 100 parts by weight of the epoxy tree++h composition.

In the above range, if the amount used exceeds 500 ffii parts, the surface roughness of the coating film will be too large, and there will be a tendency for foaming when overcoating, or the adhesion of the coating film will decrease.
When the weight is less than 1 part by weight, there is no effect of imparting roughness to the surface of the coating film (and there is no anti-slip effect at all).

In another embodiment of the present invention, at least one component selected from metal zinc powder and calcium leadate is used, but any component commonly used for paints may be used. Epoxy resin composition 10 of the components
The amount added to 0 parts by weight is 10 to 200 parts by weight, preferably 30 to 150 parts by weight.

The effect of the metal zinc powder and calcium leadate of the present invention is to further stabilize and sustain the long-term adhesion of the coating film, and it is located between the galvanized surface and the coating film, and has a buffering effect to promote adhesion. considered to be a thing. In the present invention, the use of calcium leadate alone or in combination with calcium leadate and metal zinc powder has a great effect on maintaining adhesion.

When using the two types in combination, the mixing ratio of calcium leadate and metal zinc powder is 80 to 40% by weight for the former and 2% for the latter.
0-60% by weight is most effective. If the amount of at least one component selected from the metal zinc powder and calcium leadate of the present invention is less than 10 parts by weight, there is no sustained effect on coating adhesion, and if it is more than 200 parts by weight, the adhesion tends to be impaired.

As described above, the present invention comprises an epoxy resin composition, metallic zinc powder, at least one component selected from calcium leadate, at least one compound selected from oxyacid salts, metal oxides, and a flat pigment. By using a composition in which at least one component selected from aggregate and aggregate is present in the above-mentioned ratio, it has strong adhesion to the surface of the galvanized coating and has a long-lasting effect. A long-lasting coating film can be obtained, and the flat pigment and/or aggregate provide strong adhesion to the surface of the galvanized coating and provide an anti-slip effect.

In the present invention, in addition to the above-mentioned essential components, it is also possible to add other resins that are compatible with the above-mentioned composition within a range that does not impair the object of the present invention.

Furthermore, if desired, other anti-rust pigments, extender pigments such as talc and silica, coloring pigments such as iron oxide, carbon black and titanium oxide, bituminous substances such as asphalt, tar and pitch,
Additives such as anti-settling agents, anti-sag agents, surfactants, surface conditioners, coupling agents, chelate compounds, solvents, etc. to further enhance the adhesion of the coating can be added.

In addition, in the case where an organic solvent system other than water is used as a solvent in the present invention, at least one type of organic solvent is used to assist the elution or hydrolysis of metal ions of oxyacid salts and metal oxides in the composition. It is preferable that the composition contains about 3% by weight or less of water based on the alcoholic solvent or solvent.

The coating composition comprising the above-mentioned components of the present invention is applied to a galvanized surface by a known method such as a brush, spray, roller, spatula, trowel, etc. to obtain a dry film thickness of about 10 to 1000 microns, The epoxy resin and the crosslinking agent exhibit a chemical reaction, and the coating film is cured under the conditions necessary for drying the coating film (this makes it possible to obtain a coating film having the above-mentioned effects).

Depending on the use and purpose of the steel tower, paints of various colors such as polyurethane resin paint, epoxy resin paint, chlorinated rubber paint, vinyl chloride resin paint, etc. can be applied to a thickness that does not lose the anti-slip effect of the present invention. Overcoating and epoxy resin-based or polyurethane tkl B”a
It is possible to apply the composition of the present invention after previously applying a primer.

The coating film obtained from the coating composition of the present invention exhibits strong durability against long-term exposure, and has stable adhesion over a long period of time without peeling or falling off in a short period of time as in the case of conventional coatings. It has an anti-slip effect.

Next, specific effects of the present invention will be shown by examples.

In addition, "parts" or "%" in Examples and Comparative Examples are "parts by weight"
Or it means "% by weight".

Example 1゜Using a linear bisphenol type epoxy resin with an epoxy equivalent of 450 to 500 and a polyamide resin with an active hydrogen equivalent of 150 as a crosslinking agent, the epoxy resin and crosslinking agent were added to 1 equivalent of the epoxy resin and 0.8 equivalent of the crosslinking agent. The epoxy resin composition used in the present invention was obtained by mixing in the following proportions. Other components were mixed in the proportions shown in Table-1. Compositions other than the present invention (comparative samples Nα1 to Nα4) for comparison were also obtained in the same manner.

Next, if necessary, use a mixed solvent consisting of xylene:n-butyl alcohol = 1:1 (weight ratio) to adjust the viscosity to a suitable level for painting work, so that the dry film thickness is 200 microns on the hot-dip galvanized surface. Painted, 20℃, 75%R
After drying under H conditions for 7 days, it was subjected to initial adhesion, outdoor exposure, and anti-slip tests.

=19 Example 1 Using a direct-setting bisphenol type epoxy resin having an epoxy equivalent of 900 to 1000 and an amine adduct having an active hydrogen equivalent of 200 as a crosslinking agent, the epoxy resin and the crosslinking agent were mixed in equivalent amounts to obtain an epoxy resin composition.

Compositions other than the present invention for comparison (comparative samples ib 5 to
7) was obtained in the same manner. A coating composition having the composition shown in Table 2 was prepared, and a dry film thickness of 1 was applied to the surface of a hot-dip galvanized steel sheet.
Painted to a thickness of 50 microns, 20℃, 75546
It was dried under RH conditions for 7 days and subjected to a comparative test.

In addition, when applying each paint in Example 2, the viscosity was adjusted to an appropriate level using a mixed solvent of xylene:n-butyl alcohol=1:1 (weight ratio).

-21- Comparative Experiment 1 Using the specimens of the present invention samples Nα1 to 11 and comparative samples 1 to 7 obtained as described above, a cutter was used to test the adhesion of the coating film to the initial galvanized surface. Using a knife, make 11 vertical and 11 horizontal cutting lines that cross at right angles to the galvanized surface at intervals of 3 tri in width to form 100 squares. Next, cellophane tape is pressed onto the squares, the cellophane tape is instantly peeled off, and the number of remaining squares is expressed as a percentage.

On the other hand, using another test piece, two cutting lines reaching the lead plating surface were cut diagonally across the center of the test piece, and the test piece was subjected to outdoor exposure for three years. After 3 years, the surface of the paint film was observed to confirm the presence or absence of paint film defects and abnormalities.
The adhesion quality after long-term exposure is determined for the residual coating film of the test piece using the same procedure and determination method as in the initial adhesion test. The results obtained are shown in Table 3.

Table 3 Comparative Test Results Table Comparative Experiment 2゜ Using the samples Nα1 to 11 of the present invention obtained as described above and the test samples of comparative samples Nα1 to 7, 0.5X5X5?
A rubber plate with a hook of the same shape is placed on the surface of the specimen, and a weight of IKf is placed on the surface of the rubber plate. Attach a spring scale to the hook of the rubber plate, pull the spring scale in a direction parallel to the specimen, and read the force when the rubber plate starts to move as Kg/25 art from the scale of the spring scale. The results obtained are shown in Table 4.

Table 4 It is clear from the comparative experiment results table that the coating layer obtained from the coating composition of the present invention has an extremely excellent adhesion effect to the galvanized surface. Therefore, the corrosion-proofing effect and long-term adhesion of the coating film are excellent, making it possible to protect the galvanized surface for a long period of time. In addition, it has an excellent anti-slip effect, making it extremely effective in ensuring safety when going up and down steel towers for maintenance and inspection.

Applicant Nidai Nippon Toyo Co., Ltd.

Claims (1)

[Claims] (1) (a) Epoxy resin composition containing at least two or more epoxy groups at the end and at least one or more hydroxyl group at the side chain...100 parts by weight (b) 1 to 250 parts by weight of at least one compound selected from oxyacid salts and metal oxides; ~500 parts by weight]. (2) At least one compound selected from the above-mentioned oxyacids and metal oxides, containing phosphate as an essential component and other than phosphate. The coating composition for power transmission towers according to claim (1), which comprises at least one component selected from other oxyacids and metal oxides. (3) The flat pigment and The coating composition for power transmission towers according to claim (1), wherein at least one component selected from the aggregate is flat iron oxide. Epoxy resin set (product) containing an epoxy group and at least one hydroxyl group in the side chain
Weight part. (b) Metallic zinc powder and/or calcium leadate...10 to 200 parts by weight. (C) At least one compound selected from oxyacid salts and metal oxides...
...1 to 150 parts by weight, and at least one Ji group selected from (dl flat pigments and aggregates)...
...A coating composition for power transmission towers comprising 10 to 500 parts by weight. (5) The coating composition for power transmission towers according to claim (4), wherein the component (b) is calcium leadate. (6) The coating composition for power transmission towers according to claim (4), wherein the component (b) is a mixture of metal zinc powder and calcium leadate. (7) At least one compound 1 selected from the above-mentioned oxysaccharides and metal oxides, which has a phosphate as an essential component, and at least one selected from other oxysaccharides other than phosphates and metal oxides. Claim No. 1, which is one or more components (
The coating composition for power transmission towers according to item 4). (8) A component selected from the flat pigment and the aggregate is flat iron oxide.
The coating composition for power transmission towers according to item 4).