JPS6245312B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to metal surface treatment compositions. Specifically, the present invention relates to a metal surface treatment composition that imparts high corrosion resistance and coating base properties to a metal surface and has excellent adhesion to the metal surface. Conventionally, chromate treatment or phosphate treatment has been carried out for the purpose of imparting corrosion resistance to metal surfaces and providing a coating base for improving adhesion with paints. Among these, chromate treatment provides considerable corrosion resistance, but is insufficient as a paint base agent, and in reality, phosphate treatment is used as a paint base treatment. In addition, as an improvement method for chromate treatment, for example, Japanese Patent Publication No. 1973-38891 proposes a treatment method using an inorganic chromate solution consisting of chromic anhydride and silicate, but the water resistance of the chromate film and Corrosion resistance is also insufficient. In addition, the so-called organic chromate method has been proposed in Japanese Patent Application Laid-Open No. 52-30235, etc., but these have chromic anhydride as the main component, and the resins used are ionic, nonionic, anionic, etc. The selected resin is a water-soluble resin that can be mixed uniformly with chromic anhydride. However, on the other hand, it has the drawback that its properties such as corrosion resistance are easily affected by the baking temperature, and its water resistance and alkali resistance are also insufficient. As a result of extensive research in view of the current situation, the present inventors have discovered water-dispersible silica, hydrolysates of tri- and/or dialkoxysilane compounds, cationic resins and/or zwitterionic resins, and It was discovered that by using a chromium compound, a metal surface treatment composition with excellent water resistance and alkali resistance, corrosion resistance, and paint adhesion can be obtained, and the present invention was completed. Therefore, an object of the present invention is to provide a metal surface treatment composition that imparts high corrosion resistance and coating base properties to metal surfaces, and has excellent adhesion to metal surfaces as well as workability and economic efficiency. That is, the metal surface treatment composition of the present invention contains water-dispersible silica () per 1 metal surface treatment composition.
Hydrolyzate () of tri- and/or dialkoxysilane compound (hereinafter referred to as hydrolyzate ()) in an amount ranging from 0.5 _to 250 g in terms of SiO ₂
0.5 to 600 g of cationic resin and/or zwitterionic resin () (hereinafter referred to as resin ()), and 0.05 g of chromium compound () It is characterized in that it contains an amount in the range of ~50g, and the total of (), (), (), and () does not exceed 700g. The water-dispersible silica used in the present invention is generally a condensation product of silicic acid, colloidal silica, and preferably has a particle size of 5 to 100 mμ. Examples of such water-dispersible silica include commercially available products such as "Snowtex O", "Snowtex N", and "Snowtex".
NCS”, “Snowtex 20”, “Snowtex C” (manufactured by Nissan Chemical Co., Ltd.), “Cataloid SN”,
Examples include "Cataloid Si-500" (manufactured by Catalyst Chemical Industry Co., Ltd.). In addition, surface-treated colloidal silica such as "Cataloid SA" treated with aluminic acid
(manufactured by Catalysts Kagaku Kogyo Co., Ltd.) etc. can also be used. These may be used as they are, but in order to improve their dispersibility in the metal surface treatment composition, they must be pretreated with resin () or amines such as quaternary ammonium salts, which are other essential components of the present invention. It is desirable to perform a surface treatment on the water-dispersible silica () or to graft an aziridine derivative such as ethyleneimine onto the surface of the water-dispersible silica (). The water-dispersible silica () is contained in an amount ranging from 0.5 to 250 g per metal surface treatment composition of the present invention. If the amount is less than 0.5 g, the resulting coating film will be too thin and the effect will be insufficient, whereas if it is used in excess of 250 g, the coating film will become too thick and processability will deteriorate, both of which are not preferred. A tri- and/or dialkoxysilane compound is a silane compound in which one or two organic groups and three or two alkoxy groups are bonded to a silicon atom, and specific examples include methyl trisilane. Ethoxysilane, vinyltriethoxysilane, vinyl lutris-(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane, γ-glycidoxypropyl Trimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-
γ-aminopropyltrimethoxysilane, γ-ureidopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-
Examples include (3-aminoethyl)-aminopropylmethyldimethoxysilane and γ-chloropropylmethyldimethoxysilane. Among these, γ
-Aminopropyltriethoxysilane, N-(β
-Aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-(3-aminoethyl)-aminopropylmethyldimethoxysilane, etc., when using a silane compound containing an amino group, the resin It is particularly preferred in terms of miscibility with () and dispersion stability. In order to obtain the hydrolyzate () of these tri- and/or dialkoxysilane compounds, hydrolysis may be carried out in a mineral acid such as hydrochloric acid, phosphoric acid, or sulfuric acid, or an organic acid such as formic acid or acetic acid using a conventional method. . At this time, hydrolysis may be carried out in the coexistence of water-dispersible silica () or may be carried out alone. In particular, hydrolysis in the coexistence of water-dispersible silica () is preferred because a reaction occurs between the two and they become integrated. Further, depending on the case, the hydrolysis may be carried out in the presence of the resin () or in the coexistence of both the water-dispersible silica () and the resin (). This kind of hydrolysis is
It is desirable to hydrolyze at least 50% or more, preferably almost completely, of the tri- and/or dialkoxysilane compound used. Through such hydrolysis, silicic acid and polysilicic acid derivatives with organic groups are produced, and alcohol is produced as a by-product; however, the by-produced alcohol may remain contained in the metal surface treatment composition of the present invention. Alternatively, part or all of it may be removed by conventional methods such as distillation under reduced pressure. The amount of the hydrolyzate ( ) obtained in this way is in the range of 0.1 to 250 g, preferably 0.2 to 250 g in terms of SiO ₂ per 1 metal surface treatment composition of the present invention.
Contains amounts in the range of 200g. If the amount is less than 0.1 g, no effect can be expected on a thin film, and it is also insufficient for surface treatment of water-dispersible silica. On the other hand, if it exceeds 250 g, the coating film will become too thick and the stability of the metal surface treatment composition will deteriorate, which is not preferable. The resin used in the present invention is one or more selected from the group consisting of cationic resins and amphoteric ionic resins. Among these, cationic resin refers to cationic water-soluble resin or cationic water-dispersible resin, and is a water-soluble or water-dispersible resin having cationic nitrogen in the molecule, such as the following: Examples of the resins listed in each of the sections 1 to 2 can be mentioned. Polyalkylene polyamines such as polyethyleneimine and polypropyleneimine and their derivatives. Polyamide polyamines and their derivatives produced by condensation of polycarboxylic acids and polyamines. A cationic epoxy resin obtained by reacting a polyglycidyl compound such as an epoxy resin with an amine and/or a polyamine. A cationic urea resin obtained by reacting a polyisocyanate compound such as a urethane prepolymer with an amine and/or a polyamine. Derived from one or more types selected from vinyl compounds containing amino ester groups such as dialkylaminoalkyl (meth)acrylates, and cationic nitrogen-containing vinyl compounds such as vinylpyridine, vinylimidazole, or their salts. Polymers or multicomponent copolymers of these cationic nitrogen-containing vinyl compounds and other monomers that can be copolymerized. A polymer derived from one or more monomers selected from the group consisting of diallylamine and salts thereof, or a copolymer of these monomers and other monomers copolymerizable. An aminomethyl group-containing resin obtained by reacting a chloromethyl group- and/or hydroxymethyl group-containing polymer with an amine and/or polyamine. A polycondensate of polyhaloalkane and/or epihalohydrin and/or polyepihalohydrin and amine and/or polyamine. In addition, zwitterionic resin refers to zwitterionic water-soluble resin or zwitterionic water-dispersible resin, and is a water-soluble or water-dispersible resin that has cationic nitrogen and anionic carboxyl group in the molecule. Examples of such resins include the resins shown in the following items. A resin in which a carboxyl group is introduced as an anionic group into the cationic resin of item 1 to 2 by a known method (using chloroacetic acid or the like as an example). Carboxyl group-containing resins such as (meth)acrylic resins, alkyd resins, or maleated polybutadiene, and ethyleneimine, propyleneimine, hydroxyethylethyleneimine,
Obtained by reaction with basic nitrogen-containing alkylating agents such as aziridine compounds such as 1,6-hexamethylene diethylene urea, diphenylmethane, 4,4'-N,N'-diethylene urea, and glycidylamine or its salts. Resin with zwitterionic groups. One or more basic nitrogen-containing vinyl compounds such as dialkylaminoalkyl (meth)acrylate, vinylpyridine, vinylimidazole, or their salts, and (meth)acrylic acid, crotonic acid, maleic acid, etc. A copolymer with one or more carboxyl group-containing vinyl compounds, or a multicomponent copolymer with other copolymerizable monomers. Both of these cationic resins and amphoteric ionic resins can be synthesized by common known methods. Among these cationic resins and amphoteric ionic resins, polyalkylene polyamine resins, cationic epoxy resins, homopolymers or copolymers of vinyl compounds containing amino ester groups, and cationic epoxy Zwitterionic epoxy resin obtained by ionizing amphoteric resin, Zwitterionic resin obtained by reacting a carboxyl group-containing resin with an aziridine compound,
Alternatively, a copolymer of an amino ester group-containing vinyl compound and a carboxyl group-containing vinyl compound,
It is particularly effective as the resin () in the present invention. In the present invention, various cationic resins and/or amphoteric ionic resins can be used as the resin (), for example, as shown in the above sections. However, in the case of cationic resins, the amount of cationic nitrogen measured by commonly known methods such as colloid titration, conductivity titration, etc. must be in the range of 0.1 to 24 mmol per 1 g of the resin. is desirable. In addition, in the case of amphoteric ionic resins, the amount of cationic nitrogen and the amount of carboxyl groups that can be anionized (these amounts can also be measured by colloid titration, conductivity titration, etc.) are determined per gram of the resin.
Amounts in the range 0.01 to 20 mmol are preferred. If it is outside this range, the effect as a metal surface treatment composition will be insufficient, which is not preferable. When using the resin () in the present invention, it may be used as is, or a part or all of the cationic nitrogen contained in the resin () may be replaced with an organic or inorganic acid such as hydrochloric acid, nitric acid, phosphoric acid, formic acid, or acetic acid. It can be used as a salt or a quaternary ammonium salt. Among these, if it is used as a phosphate, it is more advantageous in terms of corrosion resistance. Furthermore, when using the resin () in the present invention,
When two or more selected from the group consisting of cationic resins and amphoteric ionic resins are used together, the crosslinking reaction between the resins used is promoted, and the performance as a metal surface treatment composition is generally improved. It's advantageous. More preferably, when a cationic resin and an amphoteric ionic resin are used in combination, the cationic resin and the amphoteric ionic resin stop curing during coating film formation, resulting in a particularly effective coating with excellent water resistance and alkali resistance. . The resin () is metal surface treatment composition 1 of the present invention.
It is contained in an amount ranging from 0.5 to 600 g, preferably from 1 to 400 g. If the amount is less than 0.5 g, the adhesion between the resulting metal surface treatment composition and the metal surface will be insufficient. On the other hand, if a large amount exceeding 600 g is used, the resulting coating film becomes too thick, resulting in poor weldability and often a decrease in water resistance. The chromium compounds () used in the present invention include generally well-known CrO ₃ , Cr(NO ₃ ) ₃ ,
CrCl ₃ , Cr ₂ (SO ₄ ) ₃・18H ₂ O, CrPO ₄・6H ₂ O; Chromates such as potassium chromate and ammonium chromate; Potassium dichromate, ammonium dichromate, sodium dichromate, etc. Water-soluble chromium compounds such as dichromate; water-insoluble chromium compounds such as strontium chromate, lead chromate, and zinc chromate can be used. Among them, water-soluble chromium compounds such as chromic anhydride, chromate, and dichromate are preferred because they improve corrosion resistance even in small amounts. These chromium compounds () may be used alone or in combination of two or more, and are contained in an amount ranging from 0.05 to 50 g, preferably from 0.1 to 20 g per metal surface treatment composition of the present invention. . Among these chromium compounds (), when water-soluble chromium compounds and resin () are mixed, resin ()
Although the phenomenon differs slightly depending on the type of treatment, the reaction occurs instantaneously, forming a type of complex, and once a precipitate is formed, it can be easily redissolved or redispersed to obtain a stable treatment composition. It will be done. This is a completely different phenomenon from the case of anionic and nonionic water-soluble resins such as polyacrylic acid and polyacrylamide, which are generally used in combination with chromium compounds. The metal surface treatment composition of the present invention is composed of water-dispersible silica (), hydrolyzate (), resin (), and chromium compound (), and has a composition that is extremely thin and has excellent water resistance, alkali resistance, and corrosion resistance. However, by using a water-insoluble or water-dispersible inorganic substance in combination, it is possible to improve the surface condition and corrosion resistance of the metal to be coated. Such water-insoluble or water-dispersible inorganic substances include finely powdered silica, talc, diatomaceous earth, calcium carbonate, clay, titanium dioxide, aluminum silicate,
Examples include aluminum phosphate, alumina sol, magnesia sol, titania sol, and zirconia sol. Further, the amount used is preferably 50 g or less per 1 metal surface treatment composition of the present invention. These inorganic substances are used in a dispersed state in the metal surface treatment composition of the present invention. However, negatively charged particles may aggregate with the resin, so to avoid this, it is preferable to previously treat the surface of the particles with a cationic substance. When obtaining the metal surface treatment composition of the present invention from water-dispersible silica (), hydrolyzate (), resin () and chromium compound (), these and water may be mixed in any order. When using a chromium compound, the chromium compound ()
In order to re-disperse or re-dissolve the complex formed by the reaction between the chromium compound () and the resin (), the chromium compound () is stirred into a mixture of the water-dispersible silica (), the hydrolyzate () and the resin (). Alternatively, a preferred method is to mix the chromium compound (2) with the resin (2) with stirring, and then add the water-dispersible silica (2) and the hydrolyzate (2). As a mixing method, a usual method can be used. The scope of the present invention is not limited by these mixing order or method. Furthermore, tannic acid, gallic acid, thiourea, etc., which are generally known as components of rust preventive agents, may be added to the metal surface treatment composition of the present invention. The metal surface treatment composition of the present invention has a wide range of 0.5 to 13
Although it can be used in the PH range, it is preferably used in the PH range of 0.5 to 7, more preferably 1 to 4. If the pH is less than 0.5, excessive corrosion of the metal to be coated will occur, and if the pH exceeds 7, the reactivity with the metal surface will be too low, and in some cases, the stability of the resin will deteriorate, making it ineffective. There are some undesirable things because it becomes sufficient. This point is quite different from anionic resins. As mentioned above, it is most preferable to use phosphoric acid as a pH regulator to achieve such a preferable pH range from the viewpoint of corrosion resistance. If necessary, a small amount of an inorganic or organic acid such as hydrochloric acid, nitric acid, formic acid, acetic acid, or lactic acid may be used in combination. The metal surface treatment composition of the present invention obtained in this manner has the ability to treat metal surfaces by the combined action of water-dispersible silica (), hydrolyzate (), resin (), and chromium compound (). It has excellent adhesion to paint, excellent water resistance, alkali resistance, corrosion resistance, and coating base properties, and is also excellent in workability and economy. The metal surface treatment composition of the present invention is applicable to at least one metal or alloy selected from the group consisting of iron, steel, zinc, and aluminum, such as iron, steel, alloy steel, zinc, Metals such as zinc alloys, aluminum, aluminum alloys;
It can be used for metal coatings coated with iron, steel, alloy steel, zinc, zinc alloys, aluminum, aluminum alloys, etc., especially for zinc, zinc alloys, and metal coatings coated with them. It exhibits excellent effects. Also,
These objects to be coated can have various shapes such as a plate, a pipe, and a line. To use the metal surface treatment composition of the present invention,
Brush coating, spray coating, roll coating on the surface of the metal to be coated at room temperature to 150℃, preferably room temperature to 70℃,
After applying by dipping or other method, apply at a temperature above room temperature for a few seconds.
It only needs to dry for a few minutes. In this case, sufficient effects can be obtained with a coating film having a thickness of about 0.1 to 5 μm. The coating film of the metal surface treatment composition of the present invention obtained in this manner hardly peels off even in the adhering oil removal (degreasing) step that is generally performed in the pre-painting treatment step, and therefore, it has not been used by end users in the past. It is possible to omit the phosphate treatment step performed in In this respect as well, the metal surface treatment composition of the present invention has extremely excellent effects. Furthermore, the metal surface treatment composition of the present invention can be used not only for direct surface treatment of metal surfaces, but also for post-treatment in place of chromate sealing on conventional phosphate-treated plates. It can also be used as a sealant after conventional chromate treatment, and can also be used as a sealant that provides higher corrosion resistance and provides a good base for painting. Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited only to these examples. In addition, % in an example shall represent weight % unless otherwise specified. Example 1 Take 200 g of water-dispersible colloidal silica liquid "Snowtex 0" (manufactured by Nissan Chemical Co., Ltd., particle size 10-20 mμ, SiO ₂ content 20%), and add 6.7 mmol of cationic nitrogen with a molecular weight of about 60,000 to this. /g of polyethyleneimine/epichlorohydrin modified resin containing
Slowly add 35.8g of a 23% aqueous solution, then adjust the pH to 0.5 with phosphoric acid, slowly add 10g of γ-aminopropyltriethoxysilane, hydrolyze at 30°C for 3 hours, and then add water to the total volume. was reduced to 400ml. Next, 3 g of a 10% aqueous solution of chromic anhydride was added with stirring, and a reaction occurred instantly, forming a yellow precipitate, which redissolved as the stirring was continued. Next, by adding water to make the total volume 500ml, approximately 80g of water-dispersible silica (SiO ₂ )/
, about 5.6 g of hydrolyzate () as SiO ₂ /,
A yellow metal surface treatment composition of the present invention with a pH of 2.0 and containing about 16.9 g of a cationic resin () and 0.6 g of a chromium compound () was obtained. This is referred to as composition (A). Example 2 Epoxidized polybutadiene (trade name: BF-1000, manufactured by Adeka Argus) with a molecular weight of about 1000 and polyethyleneimine with a molecular weight of 300 were reacted, and cationic nitrogen was produced by neutralizing with hydrochloric acid and phosphoric acid. of
A cationic water-dispersible resin (PH2.0, solid content 20%) containing 2.3 mmol/g was obtained. Next, water was added to the water-dispersible colloidal silica liquid "Snowtex 0", the pH was adjusted to 1.5 with phosphoric acid, and γ-aminopropyltriethoxysilane was slowly added to the mixture at 25°C.
After hydrolysis for one day and night, by adding water, the pH
Water dispersible silica () at 3.0 as _SiO2 approx.
An aqueous dispersion (1) containing about 100 g/hydrolyzate (20 g/) was obtained. The above cationic water-dispersible resin as solid content
Take 10g and add 10% aqueous solution of chromic anhydride while stirring.
Add 5g of silica, stir vigorously to redisperse, add 400ml of water dispersion (1), and then add water to make the total volume 500ml to make water-dispersible silica () SiO ₂
Approximately 80g of hydrolyzate () as SiO ₂ /approximately 16g of cationic water-dispersible resin () as SiO2
A metal surface treatment composition of the present invention having a pH of 2.0 and containing about 1.0 g/20 g of a chromium compound () was obtained. This is referred to as composition (B). Example 3 An acrylic terpolymer with a molecular weight of approximately 200,000, consisting of 40% methyl methacrylate, 50% butyl acrylate, and 10% acrylic acid, is reacted with ethyleneimine, and then neutralized with phosphoric acid. Thus, a zwitterionic water-dispersible resin (containing 1.2 mmol/g of cationic nitrogen and 0.2 mmol/g of carboxyl groups) was obtained. Take 150g of this as a solid content, then "Snowtex 0",
SiO ₂
100g/ as SiO2, hydrolyzate () as SiO ₂ /, and cationic resin () as 20g/
and mixed with 500 ml of the containing solution. Next, add 25 g of a 10% aqueous solution of chromic anhydride, redisperse it while stirring, and add water to make a total volume of ₁₀₀₀ ml.
, about 5 g of hydrolyzate () as SiO ₂ /,
A metal surface treatment composition of the present invention having a pH of 2.0 and containing a total of 160 g of a cationic resin and a zwitterionic resin () and 2.5 g of a chromium compound () was obtained. This is referred to as composition (C). Example 4 By mixing 300 ml and 700 ml of the compositions (B) and (C) obtained in Examples 2 and 3, respectively, approximately 59 g of water-dispersible silica (SiO ₂ )/hydrolyzate was obtained. Approximately 8.3 g of () as SiO ₂ / approximately 8.3 g/approx. of cationic resin and zwitterionic resin ()
A metal surface treatment composition of the present invention having a pH of 1.9 and containing about 118 g of a chromium compound () and about 2.1 g of a chromium compound () was obtained. This is referred to as composition (D). Example 5 Take 1000 ml of the composition (C) obtained in Example 3, and add γ-glycidoxypropyltrimethoxysilane to it.
Add 50g of water-dispersible silica () to SiO ₂ by adding water after hydrolysis to make the total volume 1100ml.
Contains approximately 45.6 g/as SiO 2 , approximately 17.3 g/as SiO ₂ of hydrolyzate (), approximately 145.4 g/in total of cationic resin and zwitterionic resin (), and approximately 2.3 g/contains chromium compound (). A metal surface treatment composition of the present invention was obtained. This is referred to as composition (E). Example 6 In Example 3, methyl methacrylate - ethyl acrylate - was used instead of the zwitterionic resin.
Same as Example 3 except that a cationic water-dispersible terpolymer (containing cationic nitrogen 1.0 mmol/g) obtained by copolymerizing dimethylaminoethyl methacrylate hydrochloride was used. Approximately 50g of water-dispersible silica (SiO ₂ )/
, about 5 g of hydrolyzate () as SiO ₂ /,
A metal surface treatment composition of the present invention having a pH of 2.0 and containing about 160 g of a cationic resin ( ) and about 2.5 g of a chromium compound ( ) was obtained. Add this to composition (F)
shall be. Examples 7 to 12 Electrolytic galvanized steel sheets with a thickness of 0.5 mm were degreased, washed with water, and dried in a conventional manner to prepare test plates. Each of the metal surface treatment compositions of the present invention shown in Table 1 was roll coated onto this steel plate, and then dried at 100°C for 30 seconds to obtain a surface treated plate. Note that the film thicknesses of all these surface treatment layers were adjusted to about 0.5μ. In order to examine the primary corrosion resistance of these surface-treated plates, a salt spray test was conducted according to JIS Z-2371, and the area where white rust occurred was evaluated using a 10-point scale. That is, a score of 10 indicates that there is no area where white rust occurs, and a score of 9 indicates that the area where white rust occurs is up to 10% (the same criteria apply hereinafter). In addition, in order to check the paint adhesion and corrosion resistance after coating, alkyd melamine resin (weight ratio 7/3, PWC 50%) was coated at 140℃.
Baking was performed for 20 minutes to create a film with a thickness of approximately 30μ and a pencil hardness of 2H. As a secondary corrosion resistance test, according to JIS Z-2371, after 240 hours of the salt water spray test, cellophane tape was pressed onto the cross cut portion and then peeled off to determine the paint peeling width from the cross cut portion. In addition, to check paint adhesion, we carved 100 goblets with a 1 mm width interval, and after extruding Erichsen 5 mm, we crimped cellophane tape, peeled it off, and measured the number of remaining goblets using a 10-point scale. It was evaluated. In other words, 10 points indicates 100 remaining gobans. In addition, in order to check the water resistance, the paint-coated board was
The appearance of blisters on the coated plate after immersion in boiling water at 100°C for 3 hours was observed. Note that ○ indicates no blister, △ indicates slight blister occurrence, and × indicates blister occurrence. The results are summarized in Table 1. For comparison, in Comparative Example 1, a composition obtained by removing the chromium compound () from the composition (C) obtained in Example 3 was used, and in Comparative Example 2, a composition obtained by removing the chromium compound () from the composition (C) was used. Comparative Example 3
When using a composition excluding the hydrolyzate () from the composition (C), Comparative Example 4 used a composition excluding the water-dispersible silica () and the hydrolyzate () from the composition (C). Similar tests were conducted using the composition, Comparative Example 5 using a commercially available electrogalvanized steel sheet treated with zinc phosphate, and Comparative Example 6 using a test plate without surface treatment. was conducted and evaluated.

【table】

[Table] From the results shown in Table 1, it is clear that the metal surface treatment composition of the present invention has excellent performance in extremely thin films. Examples 13-14 Chromate-treated electrogalvanized steel sheets were treated with compositions (C) and (E) obtained in Examples 3 and 5, respectively, to a film thickness of 1.0 μm. Next, half of this treated plate was degreased with a commercially available alkaline degreaser and washed with water, and its performance was evaluated in the same manner as in Examples 7 to 12. Further, the remaining treated plates that were not subjected to degreasing were evaluated in the same manner. For comparison, Comparative Examples 7 to 10 use the compositions used in Comparative Examples 1 to 4, Comparative Example 11 uses a commercially available zinc phosphate treated plate, and Comparative Example 12
Evaluations were made using test plates without surface treatment. The results are shown in Table 2.

[Table] From the results in Table 2, it is clear that the metal surface treatment composition of the present invention has excellent alkali resistance, and its performance hardly deteriorates even in the degreasing process. Example 15 Using a commercially available chromate-treated hot-dip galvanized iron plate, a film thickness of 0.5 was obtained using the composition (E) obtained in Example 5.
After treatment to obtain a microscopic coating, a salt spray test was conducted. After 72 hours, a commercially available hot-dip galvanized iron plate will have an area of 50
% or more, but no white rust was observed in those treated with composition (E) even after 300 hours. These results show that the metal surface treatment composition of the present invention is extremely excellent as a post-treatment agent for chromate treatment. Example 16 Strontium chromate was added to the composition (E) obtained in Example 5 in an amount of 30 g/min to obtain a metal surface treatment composition of the present invention. A cold rolled steel plate (JIS G
-3141, thickness 0.8mm), treated to a film thickness of 2.0μ, coated with water-based alkyd melamine resin (weight ratio 7/3, PWC 40%), and heated at 120℃.
A film with a thickness of 30μ was created by baking for 30 minutes. A salt spray test was conducted using this product, and no abnormality was observed even after 72 hours had passed. For comparison purposes, the coated steel plate was degreased and then painted on an untreated steel plate, and blistering occurred within 24 hours, and the peeling width of the paint from the cross cut area was
It was 3.0mm. This result shows that the metal surface treatment composition of the present invention is extremely excellent as a treatment agent for steel sheets. Example 17 A commercially available aluminum-plated steel plate (trade name "Alsheet", manufactured by Nippon Steel Corporation) with a thickness of 0.6 mm was used, and the composition (E) obtained in Example 5 was used to obtain a film thickness of 1.
After treatment to obtain μ, a salt spray test was conducted. Rust was observed on the entire surface of commercially available aluminum plated steel sheets after 48 hours, but no rust was observed on those treated with composition (E) even after 300 hours. This result shows that the metal surface treatment composition of the present invention is excellent as a treatment agent for aluminum-plated steel sheets. Example 18 A commercially available zinc-aluminum alloy plated steel plate (trade name "Super Zinc", manufactured by Nippon Steel Corporation) having a thickness of 0.8 mm was degreased and washed with water in a conventional manner, and then dried to prepare a test plate. The composition (D) obtained in Example 4 was roll-coated on this plated steel plate, and then dried at 100°C for 15 seconds to obtain a surface-treated plate. The coating film thickness was 1.0μ. When a salt spray test was conducted to check the primary corrosion resistance of the surface-treated sheet, white rust appeared on almost the entire surface of the commercially available zinc-aluminum alloy plated steel sheet after 24 hours, but that of the surface-treated sheet treated with composition (D). No white rust was observed even after 72 hours. These results show that the metal surface treatment composition of the present invention is extremely excellent as a treatment agent for zinc-aluminum alloy plated steel sheets. Example 19 After degreasing and washing hot-dip galvanized steel wire with water using a conventional method,
After being immersed in the composition (F) obtained in Example 6 at room temperature for 5 seconds, it was dried with hot air at 100°C for 30 seconds. The coating film thickness was approximately 1.0μ. When we conducted a salt spray test to check the primary corrosion resistance of the steel wire, we found that the untreated steel wire
After 24 hours, white rust appeared on the entire surface, but composition (F)
No white rust was observed on the steel wire treated with this method even after 72 hours. This result shows that the composition of the present invention is extremely excellent as a treatment agent for hot-dip galvanized steel wire.

Claims (1)

[Claims] 1 Applicable to at least one metal or alloy selected from the group consisting of iron, steel, zinc, and aluminum, and 0.5 to 250 g of water-dispersible silica (in terms of SiO ₂ ) per 1 metal surface treatment composition.
The amount of the hydrolyzate of tri- and/or dialkoxysilane compound () in the range of 0.1 in terms of SiO ₂
cationic resin and/or zwitterionic resin () in an amount ranging from 0.5 to 600 g, and a chromium compound () in an amount ranging from 0.05 g to 50 g; A metal surface treatment composition characterized in that the total of (), () and () does not exceed 700g.