JP2952838B2 - Lubricated coated steel sheet with excellent deep drawability - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high performance lubricated plated steel sheet having excellent lubricity.

[0002]

2. Description of the Related Art A surface-treated steel sheet coated with a thin organic film is used in place of a post-painted steel sheet which has been coated after processing. This steel sheet has a zinc-based plating film as a base and is coated with an organic film thereon, and can be welded, and has good properties in adhesion workability and corrosion resistance.

[0003] The disclosed technology is disclosed in Japanese Patent Application Laid-Open No. 60-50 / 1985.
181 and JP-A-63-162886. The former is obtained by coating a zinc-based plated steel sheet with a resin coating material in which a chromate film and silica are dispersed in a dry film thickness of 0.01 to 4.0 μm. The latter is obtained by coating a zinc-based plated steel sheet with a chromate film and a resin coating material in which silica and a Teflon lubricant are dispersed in a dry film thickness of 0.01 to 4.0 μm to provide lubricity. These surface-treated steel sheets are plated, chromated,
Corrosion resistance, weldability,
It is being developed for the purpose of improving the quality by providing adhesion workability and lubricity.

[0004]

The prior art has been widely used for expanding the range of use, for example, for bending and shallow drawing products. However, in order to thoroughly reduce costs, save labor, and solve environmental problems in recent years,
There is an increasing demand for the development of a pre-coated lubricating steel sheet with no press oil, which is capable of responding to the high-speed and deep drawing field. High-viscosity lubricating oils have been used in high-speed deep drawing, but the quality equivalent to lubricating oils in conventional lubricating steel plates cannot be said to be sufficient. In particular, in high-speed processing, the viscoelasticity of the lubricating film changes significantly due to frictional heat between the mold and the steel sheet. In the case of a resin film with a low softening point (glass transition point; Tg point), the resin film has a high surface pressure by continuous pressing, and the film that has been peeled off by ironing and the plated metal that has been peeled off by metal-to-metal contact build up into a mold. , "Galling" occurs. In particular, water-based resin coatings have a low Tg point and are apt to seize, so that it is difficult to solve the problem with the conventional technology. However, water-based resin paints are advantageous in terms of production because they do not require solvent measures (exhaust, explosion) and are characterized by low temperature and short-time baking. Therefore, there is a demand for the development of a lubricating steel sheet using a lubricating resin that can omit press oil, particularly an aqueous lubricating resin. An object of the present invention is to provide a lubricating steel plate that solves this problem.

[0005]

The gist of the present invention is as follows. (1) 10 to 100 mg in terms of Cr on the surface of a plated steel sheet
/ M ² chromate film and resin coating containing 0.5 to 3.0 g / m ² as a dry coating amount of a resin film containing 5 to 50 parts by weight of silica as a solid based on 100 parts by weight of resin In a plated steel sheet, one or more of organic phosphorus and a phosphoric acid ester compound is 1 to 30 m in P adhesion amount.
g / m ² A lubricated plated steel sheet excellent in deep drawability characterized by being coated on the lower layer of a chromate film or contained in a chromate film.

(2) The surface of a plated steel sheet is converted to Cr by 10%.
100 mg / m ² chromate film and resin 100
Resin coated with 0.5 to 3.0 g / m ² as a dry coating amount of a resin film containing 5 to 50 parts by weight of silica and 5 to 25 parts by weight of a lubricant with respect to parts by weight. In the coated plated steel sheet, 1 to 30 mg / m ² of one or more of organic phosphorus and a phosphate compound is used as a P adhesion amount.
A lubricated plated steel sheet excellent in deep drawability characterized by being coated under the chromate film or contained in the chromate film.

[0007]

According to the present invention, a lubricating steel plate having no press oil and having a lubricating film formed between a mold and a steel plate formed on a plating surface and coated with a chromate and a resin paint has been successfully developed. Lubrication in the press is mainly lubrication with a fluid having a low coefficient of friction such as liquid and wax or an organic solid lubricant, but the high-speed deep drawing press required here requires high surface pressure and high processing speed. Because it is fast, the lubricating film with normal lubricating oil is easily broken and removed, and therefore, adhesion due to contact between the mold and the steel sheet is easy to occur,
"Gnacking" occurs. In order to solve this problem, a lubricating oil having a high viscosity and further adding various additives is used.

The lubricating action of the steel sheet of the present invention contributes to boundary lubrication for preventing the adhesion of metals in the strictest part of the press, while maintaining the press lubrication properties of the conventional fluid lubrication and solid lubricating films. It is provided by forming a film. Hereinafter, the lubricating film configuration of the steel sheet of the present invention will be described. FIG. 1 shows a sectional configuration view of the lubricated steel sheet of the present invention.

FIG. 1 (a) is a schematic diagram of a three-layer structure in which a phosphorus-based boundary lubricating film is previously formed on a plating surface, and a chromate and resin lubricating film is coated thereon, and (a) is a phosphorus-based lubricating film. (C) shows a schematic diagram of a two-layer film in which a lubricating compound-containing resin film is coated on a phosphorus-based lubricant-containing chromate film. It is. In any case, galling is prevented by the phosphorus-based lubricating film formed on the metal surface during pressing.

Hereinafter, each film and components will be described.
As the plated steel sheet, various types of plated steel sheets obtained by plating a conventional cold-rolled or hot-rolled steel sheet can be applied. The surface roughness of the steel sheet can be used for both bright and dull finishes, but it is known that roughness affects lubrication performance, and it is desirable to control the roughness within an appropriate range.

As the coated steel sheet, the present invention can be applied to a galvanized steel sheet, a zinc alloy coated steel sheet, and an aluminum plated steel sheet manufactured in an electric, hot-dip, vapor-phase plating line. The plating thickness can be applied to 1 to 20 μm which is usually produced. The phosphorus-based lubricant responsible for boundary lubrication is composed of at least one of organic phosphorus and a phosphate compound. In addition to the anti-adhesion effect of the compound itself, this film prevents metal adhesion by lubricating or chemically bonding with the new surface of the plated steel sheet generated by processing because it is chemically reactive. .

These compounds include ethyl acid phosphate, butoxyethyl acid phosphate, ethylene glycol acid phosphate, oleyl acid phosphate, oleyl hydrogen phosphite, tricresyl phosphate, dialkyl phosphite, tributyl phosphite, Organic phosphorus containing 5 to 30% of P such as thiophosphate,
It is a phosphate compound. Hydrophobic compounds can be converted to amines or alkali metal salts, or can be made hydrophilic by a surfactant.

FIG. 1 (A) shows the range of the amount of the phosphorus-based lubricating film applied.
In the case of, 1 to 30 mg / m as P ^TwoIt is. FIG.
In (a) and (c), the phosphorus-based lubricant equivalent to (a)
Total is 1 to 30 mg / m as P^TwoBlack
Mix and coat with mates and resins. 1 mg of P attached
/ M^TwoIf less than 10, a remarkable improvement effect on galling was observed.
30mg / m^TwoIn the case of super, deterioration of adhesion is practical level
Is not preferable.

Electrolytic and coating type chromate films
Although a chromate film is included in the present invention,
Is preferred. Chromate film is reduced chromic acid
One or more of silica, phosphoric acid and hydrophilic resin
Apply chromate liquid with phosphorus-based lubricant
A dried chromate film is preferred. With chromate
10-100 mg / m as chromium^TwoOf the present invention
Range. Adhesion amount as chromium is 10mg / m^TwoNot yet
In the case of full, the corrosion resistance is insufficient, and 100 mg / m ^TwoIn super
The adhesion to the lubricating resin film deteriorates, which is not preferable.

The uppermost layer of the steel sheet of the present invention comprises a resin film containing silica in a proportion of 5 to 50 parts by weight of solids with respect to 100 parts by weight of the resin, and optionally a wax lubricant for the resin. 2 to 25 parts by weight of a lubricating resin film as a base, and a film to which a fatty acid soap or an extreme pressure additive is added if necessary, as a dry adhesion amount of 0.5 to 3.
This is a lubricating resin film layer coated with 0 g / m ² .

The resins used in the present invention include acrylic resins, epoxy resins, polyester resins, olefin resins, phenolic resins, hydrophilic resins such as styrene resins, and organic solvent-based resins. Add the agent. The effect of the present invention is remarkable when a hydrophilic resin is used, and is desirable. Silica is contained for the purpose of providing corrosion resistance, strength and toughness. If the amount is less than 5 parts by weight with respect to the resin, the corrosion resistance cannot be obtained, and if the amount is more than 50 parts by weight, the workability of the film deteriorates. The most preferred silica content is 10 to 30 parts by weight. Silica is preferably silica sol for a hydrophilic resin, and dry silica is suitable for an organic solvent-based resin. Silica shape is 1
The secondary particle diameter is 2 to 50 nm and the secondary aggregation particle diameter is 100 nm
The following are suitable: In the sol, the primary particles are almost completely dispersed uniformly, whereas the dry silica is agglomerated. In addition, sols are artificially grown in a non-spherical shape, for example, in a linear shape, and are superior in quality in terms of adhesion, corrosion resistance, and the like as compared with spherical silica.

[0017] Better lubrication performance can be achieved by adding a wax lubricant in a ratio of 5 to 25 parts by weight with respect to the resin. Various waxes,
Contains fatty acid soaps and extreme pressure additives. Of these, wax is most preferred from the viewpoint of lubrication and film properties. As the wax, polyolefin (polyethylene, polypropylene) and fluorine (polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, polyvinyl fluoride) can be used. When the content is less than 5 parts by weight, a remarkable lubricating effect cannot be obtained, and when the content is more than 25 parts by weight, the corrosion resistance of the resin film and the adhesion of the top coating material are undesirably deteriorated.

The amount of adhesion of these lubricating resin films is 0.5 to
It is in the range of 3.0 g / m ² . 0.5 g / m ²
If it is less than 3.0 g / m ² , the lubricating properties and corrosion resistance aimed at by the present invention cannot be obtained, and if it exceeds 3.0 g / m ^2, there will be a problem that welding cannot be performed. Each film is applied by a known method such as a roll coater, an air knife, electrostatic coating, and electrolysis, and is baked and cured by a known method such as hot air, infrared rays, induction heating, a gas furnace, and an electric furnace.

[0019]

The present invention will be described by way of examples. The bath components in the examples are concentrations as nonvolatile components. Example 1 As shown in Table 1, an ethylene glycol acid phosphate (abbreviated as EGAP) emulsion having a P content of 21% was applied to the surface of an electrogalvanized nickel-plated steel sheet containing 12% Ni having a plating amount of 20 g / m ² as a dry adhesion amount as shown in Table 1. Coated and dried. Then, the chromium reduction ratio (Cr ³⁺ / total Cr) 0.4
Of chromic acid of 10 g / l and 30 g / l of colloidal silica was applied by a roll coater to deposit 20 mg / m ^{2 of} Cr and dried at a plate temperature of 70 ° C. After cooling, a spherical silica sol (diameter: 20 nm) dispersed in 20 parts by weight with respect to 100 parts by weight of the olefin acrylic resin was applied at a dry adhesion amount of 1 g / m ^{2, and} baked in a hot air baking furnace to a sheet temperature of 120 ° C. After cooling with water, it was dried.

The kinetic friction coefficient of the obtained resin-coated plated steel sheet and "galling" were evaluated by a rectangular cylinder crank press.
The dynamic friction coefficient was determined by applying a load of 100 g to a steel ball having a diameter of 10 mm, moving the steel ball at 100 mm / min, measuring the tension (g) with a load cell, and calculating the tension / load. The condition of the crank press is a rough plate (0.8 × 22
0 × 180 mm) to a size of 65 × 115 mm and a height of 50 mm.
The lightness was measured with a color difference meter.

The corrosion resistance was 5% in area ratio of white rust in salt spray test.
Evaluation was made based on the time of occurrence, and the coating adhesion was measured by applying a commercially available epoxy melamine resin coating at a dry adhesion amount of 20 g / m ² ,
After baking with hot air at 120 ° C. for 20 minutes, the cross Erichsen was squeezed by 9 mm, then peeled off with an adhesive tape, and visually evaluated (peeling area ratio). Table 1 shows the results. No. Comparative Example No. 1 is an example of the present invention in which EGAP was applied to the plating surface at 10 mg / m ² , and the crank press characteristics of Comparative Example No. Excellent results were obtained as compared with No. 4. No. Samples Nos. 2 and 3 showed an increase in the amount of EGAP applied, and exhibited excellent crank press properties with little galling. No. In No. 3, paint adhesion was slightly reduced.

Example 2 3 g / l of an EGAP emulsion having a P content of 21% and a chromium reduction ratio (Cr ³⁺ / total Cr) of 0.4 were applied to the surface of a galvanized nickel alloy plated steel sheet having a plating amount of 20 g / m ^2. Was applied by a roll coater with a Cr adhesion amount shown in Table 2 and dried at a plate temperature of 70 ° C. After cooling, 20 g of a spherical silica sol (20 nm in diameter) and 15 g of a polytetrafluoroethylene wax were dispersed in 100 g of an olefin acrylic resin in a dry coating amount of 1 g / m ² , and hot air was applied. Sheet temperature in baking furnace 1
It was baked at 20 ° C., cooled with water and dried. The evaluation was performed according to Example 1. Table 2 shows the results.

No. Nos. 5, 6, and 7 are examples of the present invention in which a chromate solution to which EGAP was added was applied to the plating surface and a resin to which wax was added was coated, and showed excellent results with a low coefficient of friction and almost no crank press galling. No. 8 is EG
In the comparative example in which the chromate solution to which the AP was not added was applied, galling occurred in a severely processed corner portion. Example 3 3 g / l of an EGAP emulsion having a P content of 21% and a chromic acid having a chromium reduction ratio (Cr ³⁺ / total Cr) of 0.4 were applied on the surface of an electro-zinc nickel alloy plated steel sheet having a plating amount of 20 g / m ^2. A coating type chromate solution of 10 g / l and an acrylic resin of 30 g / l was applied with a roll coater with the aim of a Cr adhesion amount of 20 mg / m ² , and dried at a plate temperature of 70 ° C. After cooling, 20 parts by weight of a linear silica sol (diameter 20 nm, length 50 nm) and 7 parts by weight of polyethylene wax were dispersed in 100 parts by weight of the olefin acrylic resin, and the resin coating was dispersed in a dry adhesion amount of 0.5 to 1.0. 3.0 g / m ^{2 was} applied, baked at a sheet temperature of 120 ° C. in a hot air baking furnace, cooled with water, and then dried. The evaluation was performed according to Example 1. Table 3 shows the results.

No. Nos. 9, 10, and 11 are examples of the present invention in which the amount of the wax-added resin applied was 0.5, 1.0, and 3.0 g / m ² . In Nos. 10 and 11, no galling occurred. No. 9 exhibited excellent crank pressability only with galling at the corners. Example 4 3 g / l of an EGAP emulsion having a P content of 21% on the surface of an electro-zinc nickel alloy-plated steel sheet having a plating amount of 20 g / m ² and a chromic acid having a chromium reduction ratio (Cr ³⁺ / total Cr) of 0.4 A coating type chromate solution of 10 g / l and an acrylic resin of 30 g / l was applied with a roll coater with the aim of a Cr adhesion amount of 20 mg / m ² , and dried at a plate temperature of 70 ° C. After cooling, 20 g of a linear silica sol (20 nm in diameter, 50 nm in length) and 15 g of a polytetrafluoroethylene wax were dispersed in 100 g of an olefin acrylic resin in a dry coating amount of 1.0 g / m ^{2 was} applied, baked at a plate temperature of 120 ° C. in a hot air baking furnace, cooled with water, and then dried. The evaluation was performed according to Example 1. The results are shown in Table 3 No. As shown in FIG. 12, very excellent crank pressability was exhibited.

Example 5 Plating amount 20 g / m^TwoElectric zinc-nickel alloy plated steel
Ethyl acid phosphate with 22% P content on the surface of the plate
(EAP) emulsion liquid as 1 g /
l, chromium reduction ratio (Cr³⁺/ All Cr) 0.4 chromic acid
10 g / l and linear silica sol (diameter 20 nm, length 50 n
m) Adhesion of chromate solution of 30g / l silica to Cr
60mg / m^TwoApply with a roll coater to aim
It was dried at a temperature of 70 ° C. After cooling, olefin acrylic resin
100 parts by weight of linear silica sol (diameter 20 nm, length
50 nm) 20 parts by weight and also polytetrafluoro
A resin paint with 15 parts by weight of ethylene wax dispersed
1.0 g / m in rye adhesion ^TwoApply and plate in hot air baking oven
It was baked to a temperature of 120 ° C., cooled with water, and then dried. Evaluation is real
It carried out according to Example 1. The results are shown in Table 3 No. 13
As shown, very excellent crank pressability was exhibited.

Example 6 P was applied to the surface of an electrogalvanized steel sheet having a plating amount of 20 g / m ^2.
3 g / l of 21% EGAP emulsion solution, 10 g of chromic acid having a chromium reduction ratio (Cr ³⁺ / total Cr) of 0.4
/ L and a coating type chromate solution of 30 g / l of colloidal silica were applied by a roll coater with a Cr adhesion amount shown in Table 4, and dried at a plate temperature of 70 ° C. After cooling, 20 g of a spherical silica sol (20 nm in diameter) and 15 g of a polytetrafluoroethylene wax were dispersed in 100 g of the aqueous emulsion resin shown in Table 4 and 1 g / m ² of dry adhesion was applied thereto. Then, the plate was baked at a plate temperature of 120 ° C. in a hot air baking furnace, cooled with water, and then dried. The evaluation was performed according to Example 1. Table 4 shows the results.

This embodiment is an example of the present invention regarding the type of resin of the uppermost resin film. No. 14 is a urethane epoxy resin; 15 is an example of an ethylene imine acrylic resin. Good results including pressability were obtained. No. No. 16 was a styrene acrylic resin whose film was hard, and a slight galling occurred at a corner by a crank press. No. No. 17 is an epoxy acryl; 18 is an example of the present invention of polyester. Good results were obtained in all aspects such as pressability.

Example 7 3 g / l of an EGAP emulsion having a P content of 21% was applied to the surface of an electrogalvanized steel sheet having a plating amount of 20 g / m ² at a chromium reduction ratio (Cr ³⁺ / total Cr).
0.4 g of chromic acid 10 g / l and colloidal silica 30 g
/ L of a coating type chromate solution was applied by a roll coater with a Cr adhesion amount shown in Table 5, and dried at a plate temperature of 70 ° C. After cooling, dry silica (primary particle size 20 nm, secondary aggregate particle size 5
0 nm), 20 parts by weight of dry silica (primary particle diameter: 20 nm, secondary aggregation particle diameter: 50 nm), 15 parts by weight of polytetrafluoroethylene wax, and 3 parts by weight of EGAP based on 100 parts by weight of the resin diluted with the organic solvent shown in Table 5. 1 g / m ^{2 of} the resin coating material in which the parts were dispersed was applied in a dry adhesion amount, baked at a plate temperature of 150 ° C. in a hot air baking furnace, cooled with water, and dried. The evaluation was performed according to Example 1. Table 5 shows the results.

In this embodiment, an organic solvent-dilutable resin is used. No. 19, 20, 21 and 22 all show excellent press characteristics without galling.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

[Table 4]

[0034]

[Table 5]

[0035]

The steel sheet of the present invention does not require the use of a chlorine-based solvent used for removing press oil, thus contributing to the prevention of environmental pollution. Because it is simplified, it has the effect of labor saving and beautiful work environment. In addition, since the steel sheet of the present invention is excellent in corrosion resistance, the step of coating after the conventional processing can be omitted.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration diagram of a film of the present invention.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C25D 5/26 C25D 5/26 P 11/38 301 11/38 301Z

Claims (2)

(57) [Claims] 1. The surface of a plated steel sheet is 10 to 1 in terms of Cr.
A chromate film of 00 mg / m ² and a resin film containing silica at a ratio of 5 to 50 parts by weight as a solid content with respect to 100 parts by weight of the resin are 0.5 to 3.0 g as a dry adhesion amount.
/ M ² coated resin-coated steel sheet coated with 1 to 30 mg / m ² of the organic phosphorus or phosphate compound as a P adhesion amount in the lower layer of the chromate film or contained in the chromate film Lubricated coated steel sheet with excellent deep drawability characterized by: 2. The surface of a plated steel sheet is 10 to 1 in terms of Cr.
A dry coating amount of a resin film containing 5 to 50 parts by weight of silica and 5 to 25 parts by weight of a lubricant based on 100 mg by weight of a 00 mg / m ² chromate film and 100 parts by weight of a resin. In a resin-coated plated steel sheet coated with 3.0 g / m ² , at least one of organic phosphorus and a phosphate compound is coated as a P coating amount on a lower layer of 1-30 mg / m ² chromate film or in a chromate film. Lubricated coated steel sheet with excellent deep drawability characterized by containing.