JP2998792B2 - Surface treated metal plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-treated metal plate excellent in deep drawability, and more particularly to a component of household electric appliances, such as an audio chassis, a computer case, and the like.
The present invention relates to a surface-treated metal plate suitable for deep drawing products such as a video case, a motor case, and a pulley.

[0002]

2. Description of the Related Art Materials used for parts of household electrical appliances include Zn-based steel sheets such as electro-galvanized steel sheets and hot-dip galvanized steel sheets, and Zn-based steel sheets for the purpose of further improving corrosion resistance and paintability. Inorganic surface-treated steel sheets obtained by subjecting a plated steel sheet to a chemical conversion treatment such as a chromate treatment or a phosphate treatment are widely used.

[0003] These inorganic surface-treated steel sheets are shipped as a coil material or a sheet material from a steel sheet maker as a product, and subjected to various processes by a user. However, since these surface-treated steel sheets are formed of a hard inorganic coating on the surface, they come into contact with the transfer table or rub against the metal mold during bending, causing scratches on the steel sheet surface. May occur. Scratches on the steel sheet surface impair the appearance and film performance of the product and degrade its commercial value.

Therefore, a resin-coated steel sheet having an organic resin film formed on a surface-treated steel sheet subjected to a chromate treatment (Japanese Patent Application Laid-Open Nos. 58-153785 and 58-17747).
No. 6 publication). In the case of this resin-coated steel sheet, since the surface is covered with the resin film, an effect is recognized on the scratch resistance. However, in the case of parts that are subjected to deep drawing, such as motor cases, intense sliding friction occurs with the mold, causing the resin film on the sliding surface to peel and blacken. This causes a problem that the appearance of the product is remarkably impaired, and that the blackened matter adheres to other equipments to cause another problem.

[0005] In order to solve the above-mentioned problems of the resin-coated steel sheet, a lubricating steel sheet in which a film having an inorganic polymer compound and a solid lubricant is formed as a resin film (JP-A-6-57442). Or a lubricated steel sheet on which a film having an aqueous resin is further formed (Japanese Patent Laid-Open No. 6-57441).
Publication). The film-treated steel sheet based on these inorganic polymers has an effect of improving the scratch resistance and the occurrence of black matter in the film during deep drawing.
However, when applying the solution to the steel plate, coating defects such as repelling may occur and the water permeability of the film is high, so black spot-like rust and white rust easily occur, and when coating is performed Had a defect such as poor adhesion of the coating film. That is, although the scratch resistance and the deep drawability were improved, there were problems in terms of corrosion resistance and paintability.

Further, depending on the type of solid lubricant contained in the film, the solvent resistance is low, and when the surface is degreased with an organic solvent, the solid lubricant dissolves and pores are formed in the film. In some cases, the corrosion resistance may be significantly degraded. Therefore, improvement in corrosion resistance after degreasing with an organic solvent has been demanded.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is a resin film-coated metal plate having excellent scratch resistance and deep drawability, and having excellent corrosion resistance and coating properties. Moreover, it is an object of the present invention to provide a surface-treated metal plate having improved corrosion resistance after degreasing with an organic solvent.

[0008]

According to the present invention, there is provided a film comprising an alkali metal silicate or an alkali metal silicate and a silicate colloid, and further comprising an organic resin and a solid lubricant. Surface treated metal plate,
The alkali metal silicate is lithium silicate, the (Li atom / Si atom) ratio (hereinafter referred to as Li / Si ratio) in the coating is 0.2 to 0.6, and the organic resin is However, the gist is that the linear polymer is present in the network structure of the crosslinked organic resin.

The content of the organic resin in the film is as follows:
The content of the linear polymer in the organic resin is preferably from 2.0 to 10.0% by weight.
It is desirable to use 40.0% by weight, and it is desirable to use an acrylic resin as the cross-linkable organic resin and to use a high molecular fatty acid ester as the linear polymer.

It is recommended that the content of Na and / or K present as an impurity in the alkali metal silicate is 1.0% by weight or less in total, and the amount of the coating film is 0.025% in terms of Si. It is desirably about 0.5 g / m ² .
Further, a silane coupling agent is added to the film in an amount of 1.0 to 1
By containing 0.0% by weight, it is possible to improve the coating property (secondary adhesion) and the printability.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have developed a metal plate coated with a resin film having excellent deep drawability, and a surface-treated metal plate having excellent overall corrosion resistance, including corrosion resistance after degreasing with an organic solvent, and excellent coatability. We worked diligently to develop it. As a result, lithium silicate is selected as the metal silicate which is the main component of the coating, and the Li / Si ratio in the coating is controlled within a specific range, thereby ensuring excellent deep drawability. It has been found that a film excellent in corrosion resistance and paintability can be formed. Furthermore, by using resin particles containing a linear polymer as a lubricant (hereinafter referred to as “lubricant-containing resin”) in a gap of the network structure of the cross-linkable organic resin, the solvent resistance is improved. The present inventors have found that it is possible to prevent the deterioration of corrosion resistance after degreasing by an organic solvent by increasing the organic solvent, and arrived at the present invention.

If the Li / Si ratio is too small, the film-forming properties of the film deteriorate and the film is easily repelled even when applied to a metal plate, and a film having excellent adhesion cannot be formed, so that the corrosion resistance deteriorates. As well as being easily scratched. Therefore, Li / Si
The ratio needs to be 0.2 or more. On the other hand, Li /
If the Si ratio is too large, the adhesion of the coating film when coated is deteriorated. Therefore, the Li / Si ratio needs to be 0.6 or less. As described above, in the present invention, the Li / Si ratio of the aqueous solution of lithium silicate or the Li / Si ratio in the mixture of the aqueous solution of lithium silicate and the colloid of silicate are described.
It is necessary to set the ratio to 0.2 to 0.6,
A range of 0.4 is more preferable.

The method of introducing a lubricant into the organic resin is not particularly limited, but for example, Semi-IP
If N (Interpenetrating Networks: Interpenetrating Crosslinking Method) is used, a linear polymer is polymerized inside the network structure of the crosslinked organic resin, and a lubricant-containing resin can be produced. FIG. 1 is an explanatory view schematically showing the above-mentioned lubricant-containing resin, and a fibrous linear polymer (hereinafter, sometimes referred to as a lubricant) as a lubricant between gaps of an organic resin network structure.
Is woven.

As the resin for introducing the lubricant, a cross-linkable organic resin may be used, and a thermosetting resin may be used, but an acrylic resin is recommended, and an acrylic resin, an acrylic-styrene copolymer, urethane Modified acrylic resins, urethane-modified acrylic-styrene copolymers and the like can be exemplified. On the other hand, as the lubricant which is a linear polymer, it is preferable to use a high-molecular fatty acid ester.

In the surface-treated metal sheet of the present invention, an organic resin is added for the purpose of improving the film forming property and corrosion resistance of the film. When the content of the organic resin is less than 0.5% (% by weight, hereinafter abbreviated), the effect of improving the film forming property and corrosion resistance by adding the organic resin is not sufficient. On the other hand, when the content of the organic resin is more than 10.0%, the blackening phenomenon in which the resin on the sliding surface peels and blackens easily occurs by performing deep drawing, and the appearance after the processing is improved. Deteriorate. Therefore,
In the present invention, the content of the organic resin is 0.5 to 10.0.
%. In addition, it is preferable that it is 2.0% or more and 7.0% or less.

In addition, if the content of the lubricant contained in the lubricant-containing resin in the present invention is too small, the effect of improving the lubricity cannot be obtained, so that it is preferable to be 2.0% or more. On the other hand, if the amount is too large, not only the effect of improving the lubricity of the lubricating film is saturated, but also the stability of the base resin particles is impaired, and the workability and corrosion resistance are deteriorated. Therefore, the content of the lubricant contained in the lubricant-containing resin is preferably set to 40% or less.

In the present invention, the solution applied for the purpose of forming a film may be an aqueous solution of lithium silicate alone or a solution of lithium silicate as long as it satisfies the above Li / Si ratio of 0.2 to 0.6. A mixed solution of an aqueous solution and a silicate colloid may be used, and it can be obtained by adding a lubricant-containing resin to this.

Therefore, in producing the surface-treated metal plate according to the present invention, an aqueous solution of lithium silicate or a mixture of an aqueous solution of lithium silicate and colloidal silicate is applied to the surface of the metal plate and dried to obtain fine silica particles. Can be formed on the surface of the metal plate.

As the lithium silicate, a commercially available lithium silicate may be used, and a commercially available colloidal silica or a colloid sol may be used for the silicic acid colloid. Contains sodium and potassium silicate.
Sodium silicate and potassium silicate deteriorate the wettability between the coating solution and the steel sheet during coating, and when dried to form a film, defects are generated in the obtained film, causing corrosion resistance and adhesion to decrease. . Therefore, it is desirable to control the content of Na and / or K contained in the film to 1.0% or less in total.

The amount of the film formed on the surface of the metal plate is preferably in the range of 0.025% to 0.5 g / m ^{2 by} weight of Si. When the coating weight is less than 0.025 g / m ^{2 in} terms of Si, a tough and hard vitreous coating cannot be obtained, and sufficient corrosion resistance and deep drawability cannot be obtained. On the other hand, when the coating amount is more than 0.5 g / m ^{2 in} terms of Si, the grounding property and coating property of the coating deteriorate.

The present invention is not limited by the method of applying the coating liquid, and may be arbitrarily selected from known coating methods such as a roll coater method, a knife coater method, and a spray method.

The material of the base for forming the film according to the present invention is not particularly limited, and a metal plate such as an aluminum plate, an aluminum alloy plate, a stainless steel plate, a titanium plate and the like can be used other than the steel plate. However, in consideration of the adhesiveness to the material at the time of forming the film, a material obtained by subjecting a Zn or Zn alloy plated steel sheet to a chemical conversion treatment such as a chromate treatment or a phosphate treatment is preferably used.

In particular, as the chemical conversion treatment applied to the Zn or Zn alloy plated steel sheet, a Zn or Zn alloy plated steel sheet subjected to chromate treatment is most preferable from the viewpoint of corrosion resistance. In this case, the amount of the chromate film adhered is preferably 10 mg / m ² or more as the amount of Cr adhering from the viewpoint of corrosion resistance. On the other hand, the upper limit of the amount of Cr adhering is 100 mg / m ² from the viewpoint of adhesion to the film. Is preferred. still,
As a method of performing chromate treatment, a washing type (reaction type)
There are methods such as chromate treatment, coating type chromate treatment, and electrolytic chromate treatment, but the method is not particularly limited.
Any method can be used.

As described above, according to the present invention, a coating-coated metal sheet having excellent scratch resistance and deep drawability, having excellent corrosion resistance and coating properties, and having improved corrosion resistance after degreasing with an organic solvent. A surface-treated metal plate can be provided.

Further, in the case of parts such as home electric appliances, characters or figures are generally printed by silk printing or the like in addition to painting. In these applications, characters or lines after printing are blurred. It is required to print clearly without repelling. When printability is required for the surface-treated metal plate as described above, it is recommended to include a silane coupling agent in the film according to the present invention.

Further, by containing a silane coupling agent, not only the adhesion after coating (primary adhesion) but also the
It is also possible to improve coating film adhesion (secondary adhesion) after dipping in boiling water after coating. Although the mechanism of improving the adhesion of the coating film of such a silane coupling agent has not been completely elucidated, alcohol groups and silanol groups are generated by hydrolysis of an alkoxy group bonded to silicon in an aqueous solution. It is presumed that the generated silanol groups strengthen the bonding force with the coating film after coating.

With respect to the alkoxy group bonded to silicon in the silane coupling agent, the effect of improving the coating film adhesion is presumed to be due to the silanol group generated by the hydrolysis of the alkoxy group. It is preferably a lower alkoxy group such as a methoxy group or an ethoxy group. Among these, the alkoxy group is more preferably a methoxy group having a low boiling point of the alcohol generated by hydrolysis, considering that the alcohol generated after hydrolysis has an adverse effect on the film-forming properties of the film. As the silane coupling agent, a general silane coupling agent represented by the following formula (1) or (2) can be used.

[0028]

(Equation 3)

(R ₁ , R ₅ ; lower alkyl group, R ₂ , R
₍₃ , R ₄ ; lower alkoxy group) As described above, the present invention does not limit the kind of the silane coupling agent to be contained, but from the viewpoint of dispersibility and compatibility in an aqueous solution, the following (3) It is preferable to use a silane coupling agent having a glycidoxy group at the terminal as shown in the formula (4) or (4).

[0030]

(Equation 4)

(R _g : glycidoxy group, R ₂ , R ₃ , R
₄ ; a lower alkoxy group, R ₅ ; a lower alkyl group, R ₆ ;
Lower alkylene group)

The content of the silane coupling agent is 1.
When the amount is less than 0%, the effect of improving the adhesion of the coating film is insufficient, and a steel sheet having excellent adhesion to the coating film after coating, particularly secondary adhesion and printability cannot be obtained. When it is more than 0%, the effect of improving the coating film adhesion, particularly the secondary adhesion, is saturated, and the formed film becomes brittle, adversely affecting workability. It is recommended that the content be 1.0 to 10.0%.

As described above, the silane coupling agent has a remarkable effect on improving the secondary adhesion and printability of the coated film, but the printability and coatability are sufficient only by adding the silane coupling agent. Is not obtained, lithium silicate is selected as the main alkali metal silicate, the Li / Si ratio in the film is controlled, and the contents of Na and K contained in the alkali metal silicate are selected. By optimizing the surface treatment, it is possible to obtain, for the first time, a surface-treated metal plate excellent in primary adhesion, secondary adhesion and printability after coating.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the following examples do not limit the present invention. It is included in the technical range of.

[0035]

EXAMPLE 1 First, the following experiment was carried out for the purpose of examining the effect of the Li / Si ratio in the treatment liquid on corrosion resistance, scratch resistance, wettability and paintability.

As the metal plate, a chromate-treated electric Zn-plated steel sheet (Zn adhesion 20 g / m ² , Cr adhesion 20 mg / m ² , plate thickness 0.8 mm) was used. In a mixed solution of lithium silicate and colloidal silicate, Semi-I
4. Using PN, a lubricant-containing resin in which 20% of a high-molecular fatty acid ester is present in the network structure of an acrylic resin.
The treatment liquid containing 0% was applied to the surface of the above-mentioned original plate with a squeezing roll such that the Si weight after application and drying was 0.2 g / m ^2, and dried at a plate temperature of 80 ° C. Was formed to produce a surface-treated steel sheet. In addition, the said mixed solution adjusted the compounding quantity of a lithium silicate and a silicic acid colloid, and Li / Si ratio was No. 0 in the range of 0-1.0. 1 to 12 test pieces were obtained.

The test pieces were tested for corrosion resistance, scratch resistance, wettability, and paintability as follows. (i) Corrosion resistance test A salt spray test was carried out according to JIS Z2371.
The corrosion resistance was evaluated based on the area of white rust generated after 00 hours.
The evaluation criteria are shown below. ：: no white rust ○: less than 5% white rust Δ: 5% or more and less than 10% ×: 10% or more white rust

(Ii) Scratch resistance test Using a surface property tester (manufactured by HEIDON), two test materials were stacked, and abrasion due to mutual sliding was generated.
The flaw was visually evaluated. The evaluation criteria are shown below.
In addition, the upper one of the above two stacked test materials has a dimension of 1.
The size was 0 mm x 10 mm, and the load during sliding was 1 kg. ◎: extremely good (no flaws) ○: good (some flaws are seen but no problem) △: bad (flaws are noticeable) ×: extremely bad (flaws are noticeable)

(Iii) Wettability test The coating solution was applied on a steel plate with a squeezing roll, and the repellency of the surface after drying was visually observed and evaluated according to the following criteria. ◎: extremely good (no repelling at all) ：: good (slight repelling at the edge but no problem) △: bad (significant repelling at the edge or partial repelling at the center ×): extremely poor (repelling is remarkable over the entire surface)

(Iv) Paintability test A melamine-based paint was applied to the obtained coated steel sheet to a thickness of 20 μm.
After baking at 150 ° C. for 30 minutes, 100 square grids of 1 mm square are put with a cutter knife, and a tape peeling test is performed on the square grid. The film adhesion was evaluated. Li of each mixed solution
Table 1 shows the / Si ratio and test results.

[0041]

[Table 1]

Inventive Example No. satisfying the Li / Si ratio: 0.2 to 0.6. Nos. 1 to 6 are excellent in all of corrosion resistance, scratch resistance, wettability and paintability. On the other hand, Comparative Example No. in which the Li / Si ratio was too small. In Comparative Examples Nos. 7 to 9, the corrosion resistance, scratch resistance and wettability were poor and the Li / Si ratio was too large. 10-12 are inferior in paintability.

Example 2 Next, the effects of the linear polymer content in the lubricant-containing resin and the content of the lubricant-containing resin in the treatment liquid on the surface-treated steel sheet were examined. Using Semi-IPN, a lubricant-containing resin in which 0 to 50% of a high-molecular fatty acid ester was introduced as a linear polymer as a lubricant in a network structure of an acrylic resin was prepared. A coating solution which is a mixture of an aqueous solution of lithium silicate and a colloid of silicate, wherein a treatment solution is prepared by adding 0 to 15% by weight of the lubricant-containing resin to a mixed solution having a Li / Si ratio of 0.4. Except that No. was used in the same manner as in Example 1. 13 to 70 surface-treated steel sheets were obtained.

Further, in place of the lubricant-containing resin, a particle size of 0.1.
6 μm water-dispersible polyethylene wax particles 2.0 to 1
Except that 0.0% and 1.0 to 2.0% of the acrylic resin were separately added, the same procedure as in Example 1 was repeated. 7
1 to 76 surface-treated steel sheets were obtained.

With respect to these surface-treated steel sheets, a corrosion resistance test and a wettability test were performed by the methods described above, and a deep drawability testability and a corrosion resistance test after solvent degreasing were performed by the following methods.

(V) Deep drawing workability test A single-shot press test was performed using an 80-ton crank press device, and the sliding surface of the molded product was subjected to mold galling and blackening (blackening resistance). ) Was evaluated visually to determine the deep drawability. The evaluation criteria are shown below. ◎: No mold seizure or blackening phenomenon observed ○: Slightly observed, but no problem level Δ: Mold seizure or blackening phenomenon noticeable ×: Mold seizure or blackening phenomenon noticeably noticeable

(Vi) Corrosion resistance test after solvent degreasing A test piece was subjected to steam degreasing using trichloroethylene for 1 minute, and then subjected to a salt spray test according to JISZ2371. The corrosion resistance was evaluated as follows. ：: no white rust ○: less than 5% white rust Δ: 5% or more and less than 10% white: 10% or more white rust The results are shown in Tables 2 and 3.

[0048]

[Table 2]

[0049]

[Table 3]

Inventive Example No. 13 to 48, the content of the lubricant-containing resin in which the amount of the linear polymer is 2.0 to 40.0% in the film is 0.5 to 10.0%,
Excellent overall corrosion resistance, including corrosion resistance after degreasing, deep drawability, and wettability.

On the other hand, in Comparative Example No. in which the amount of the linear polymer introduced into the lubricant-containing resin and the content of the lubricant-containing resin in the treatment liquid did not satisfy the range of the present invention. 49-6
No. 9 is inferior in corrosion resistance, deep drawability, or wettability, and has too much linear polymer. 70
No film could be formed due to poor stability of the resin emulsion. In addition, No. 1 using a treatment liquid to which a solid lubricant and an organic resin were separately added was used. 71-76 are
It can be seen that the corrosion resistance after degreasing is poor.

Example 3 Next, the relationship between the contents of Na and / or K in the treatment liquid and the properties of the obtained surface-treated steel sheet was examined. In a mixed solution of lithium silicate and colloidal silicate, wherein the Li / Si ratio is 0.4, sodium silicate and / or potassium silicate are mixed with Na and / or K in an amount of 0 to 0.
Except that it was added varying in the range of 3.0% by weight,
In the same manner as in the first embodiment, 77 to 83 surface-treated steel sheets were obtained. For these surface-treated steel sheets,
A corrosion resistance test, a wettability test, and a deep drawing workability test were performed in the same manner as in Example 2. The results are shown in Table 4.

[0053]

[Table 4]

The content of Na and / or K is 1.0% by weight
The present invention example No. Nos. 77 to 80 are excellent in all of corrosion resistance, wettability and deep drawing workability. On the other hand, in Comparative Example No. 1 in which the content of Na and / or K exceeds 1.0% by weight. 81
-83 are inferior in corrosion resistance and wettability.

Example 4 Next, the relationship between the amount of coating film and the properties of the resulting surface-treated steel sheet was examined. A coating solution obtained in the same manner as in Example 1 except that a mixture of lithium silicate and colloidal silicate having a Li / Si ratio of 0.4 was used. And dried in the same manner as in Example 1 so that the concentration becomes 0.025 to 1.2 g / m ^2.
o. 84 to 92 were obtained.

For these surface-treated steel sheets, a corrosion resistance test and a deep drawability test were performed in the same manner as in Examples 1 and 2, and the surface resistance was measured with a tester to evaluate the grounding properties as follows. . ◎: less than 50Ω ○: 50Ω or more and less than 100Ω Δ: 100Ω or more and less than 200Ω ×: 200Ω or more The results are shown in Table 5.

[0057]

[Table 5]

The amount of Si adhesion is 0.025 to 0.5 g / m ²
Of the present invention satisfying the range of the present invention. Nos. 84 to 89 are excellent in all of corrosion resistance, deep drawing workability and earthing property. On the other hand, Comparative Example No. 1 in which the amount of deposited Si was too small Comparative Example No. 90 is poor in corrosion resistance and deep drawability and has too much Si adhesion. 91 and 92 are inferior in grounding properties. Examples 5 to 9 shown below were performed for the purpose of examining the characteristics of the surface-treated metal plate when the silane coupling agent was added.

Example 5 A Li / Si ratio of 0 to 1.0 was prepared in the same manner as in Example 1 except that γ-glycidoxypropyltrimethoxysilane was contained at 5.0% by weight as a silane coupling agent. No. in the range of No. 101 to 112 test pieces were obtained. These specimens were tested for corrosion resistance, scratch resistance, wettability, and paintability (primary adhesion) by the methods described above. In addition, paintability (secondary adhesion) and printability were determined by the following methods. Was examined.

(Vii) Paintability Test (Secondary Adhesion) Each of the coated test pieces was immersed in boiling water for 1 hour, allowed to stand at room temperature for 1 hour, and then subjected to the same method as in the primary adhesion to measure the remaining amount of the coating. The secondary adhesion was evaluated by the number of stitches.

(Viii) Printability test The obtained steel sheet was 0.2 m thick by silk screen printing.
m, 0.5 mm, and 1.0 mm lines were printed, and the sharpness of each line after printing was visually evaluated. The printing was performed using an epoxy paint and the baking conditions were 40 ° C. × 20 minutes. The evaluation criteria are shown below. ◎: No bleeding or bleeding ○: Slight bleeding is observed but no problem is observed △: Repelling or bleeding is noticeable ×: Repelling or bleeding is remarkable Table 6 shows the Li / Si ratio of each mixed solution and test results. Shown in

[0062]

[Table 6]

In the present invention, the Li / Si ratio is in the range of 0.2 to 0.6. Nos. 101 to 106 are excellent in all of corrosion resistance, scratch resistance, wettability, paintability and printability. On the other hand, in Comparative Example No. where the Li / Si ratio was too small. 107-1
Comparative Example No. 09 is inferior in corrosion resistance, scratch resistance and wettability, and the Li / Si ratio is too large. 110
-112 are inferior in coatability and printability.

Example 6 Except that 5.0% by weight of γ-glycidoxypropyltrimethoxysilane was added as a silane coupling agent, the amount of linear polymer present in the lubricant-containing resin was the same as in Example 2. And, the content of the lubricant-containing resin in the processing liquid,
The effect on the surface-treated steel sheet was investigated. The results are shown in Tables 7 and 8.

[0065]

[Table 7]

[0066]

[Table 8]

Inventive Example No. Nos. 113 to 148 indicate that the content of the lubricant-containing resin in which the linear polymer is present in an amount of 2.0 to 40.0% in the film is 0.5 to 10.0%, such as corrosion resistance after degreasing. It has excellent overall corrosion resistance, deep drawability, wettability, and printability.

On the other hand, in Comparative Example No. 1 in which the amount of the linear polymer introduced into the lubricant-containing resin and the content of the lubricant-containing resin in the treatment liquid did not satisfy the range of the present invention. 149 ~
No. 169 is inferior in corrosion resistance, deep drawability, or wettability, and has too much linear polymer.
In No. 170, a film could not be formed due to poor stability of the resin emulsion.

Further, in the case of No. 3 using a treatment liquid in which a solid lubricant was added separately from an organic resin instead of a linear polymer as a lubricant. 171-176 (No. 71-76 of Example 2)
) Is inferior in corrosion resistance after degreasing.

Example 7 In the same manner as in Example 3 except that 5.0% by weight of γ-glycidoxypropyltrimethoxysilane was contained as a silane coupling agent, Na and / or K in the treatment liquid were changed. Was examined for the relationship between the content of C and the properties of the resulting surface-treated steel sheet. The results are shown in Table 9.

[0071]

[Table 9]

The content of Na and / or K is 1.0% by weight
The present invention example No. 177 to 180 are excellent in all of corrosion resistance, wettability and deep drawability. On the other hand, in Comparative Example No. 1 in which the content of Na and / or K exceeds 1.0% by weight.
181 to 183 are inferior in corrosion resistance and wettability.

Example 8 Next, the relationship between the content of the silane coupling agent in the treatment liquid and the properties of the surface-treated steel sheet was examined. Li / Si ratio of 0.4
The test piece No. was prepared in the same manner as in Example 1 except that the silane coupling agent shown in Table 10 below was contained in an amount of 0 to 20.0% by weight. 184 to 196 were prepared, and the deep drawability and the paintability were examined by the above-described method.

[0074]

[Table 10]

The silane coupling agent is used in an amount of 1.0 to 10.0.
Inventive Example No. contained in the range of% by weight. 184-19
No. 1 is excellent in both deep drawability and paintability. On the other hand, when the silane coupling agent was not added or the content was too small, the comparative example No. 192,1
Comparative Example No. 93 was poor in secondary adhesion and contained too much silane coupling agent. In the case of 194 to 196, mold seizure occurred during deep drawing.

Example 9 Except that 5.0% by weight of γ-glycidoxypropyltrimethoxysilane was contained as a silane coupling agent, the adhesion amount of a glassy film and the yield were obtained in the same manner as in Example 4. The relationship between the properties of the surface-treated steel sheets obtained was investigated. The results are shown in Table 11.

[0077]

[Table 11]

The Si adhesion amount is 0.025 to 0.5 g / m ²
Of the present invention satisfying the range of the present invention. 197 to 202 are excellent in all of corrosion resistance, deep drawing workability and earthing property.
On the other hand, Comparative Example No. 1 in which the amount of deposited Si was too small Comparative Example No. 203 is poor in corrosion resistance and deep drawability and has too much Si adhesion. 204 and 205 have poor grounding properties.

[0079]

Since the present invention is constituted as described above, it is a metal plate coated with a resin film having excellent scratch resistance and deep drawability, which is excellent in corrosion resistance and paintability, and after degreasing with an organic solvent. Can provide a surface-treated metal plate with improved corrosion resistance. Further, it has become possible to provide a surface-treated metal plate which is excellent in secondary adhesion and printability in addition to the above characteristics.

[Brief description of the drawings]

FIG. 1 is a schematic diagram schematically showing an interpenetrating crosslinking method.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-60886 (JP, A) JP-A-6-57441 (JP, A) JP-A-52-76236 (JP, A) JP-A-62 284003 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C23C 22/00-22/86

Claims (10)

(57) [Claims] 1. A surface-treated metal plate on which a coating containing an alkali metal silicate or an alkali metal silicate and a silicate colloid and further containing an organic resin is formed, wherein the alkali metal silicate is lithium silicate. In addition, the (Li atom / Si atom) ratio in the film is 0.2 to 0.6, and the organic resin has a linear polymer in a network structure of a crosslinked organic resin. A surface-treated metal plate, characterized in that: 2. The organic resin content in the coating is 0.5
The surface-treated metal sheet according to claim 1, wherein the amount is from about 10.0% by weight. 3. The surface-treated metal sheet according to claim 1, wherein the amount of the linear polymer in the organic resin is 2.0 to 40.0% by weight. 4. The surface-treated metal plate according to claim 1, wherein the cross-linkable organic resin is an acrylic resin. 5. The surface-treated metal plate according to claim 1, wherein the linear polymer is a high-molecular fatty acid ester. 6. The film according to claim 1, wherein the total content of Na and / or K contained as impurities in the alkali metal silicate and / or silicate colloid is not more than 1.0% by weight in the film. A surface-treated metal plate according to item 1. 7. The coating amount of the coating is from 0.025 to 0.025 in terms of Si.
Surface-treated metal sheet according to any one of claims 1 to 6 is 0.5 g / m ^2. 8. The surface-treated metal sheet according to claim 1, wherein the coating contains a silane coupling agent in an amount of 1.0 to 10.0% by weight. 9. The surface-treated metal sheet according to claim 8, wherein the silane coupling agent is at least one selected from the group consisting of silane coupling agents represented by the following formula (1) or (2). . (Equation 1) (R ₁ , R ₅ ; lower alkyl group, R ₂ , R ₃ , R ₄ ; lower alkoxy group) 10. The surface-treated metal sheet according to claim 8, wherein the silane coupling agent is at least one selected from the group consisting of a silane coupling agent represented by the following formula (3) or (4). . (Equation 2) (R _g ; glycidoxy group, R ₂ , R ₃ , R ₄ ; lower alkoxy group, R ₅ : lower alkyl group, R ₆ : lower alkylene group)