JPH10114012A - Surface lubricating treatment metallic material with excellent marring resistance and film-removing property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film-removing type surface lubricating treatment metallic plate in which the whole performance such as marring resistance, lubricating properties, blocking resistance and film-removing properties necessary at time of plastic working is satisfied and applied to a metallic material having a pretty surface such as a stainless steel plate and an aluminum-based plated steel sheet. SOLUTION: Water-based treating liquid is applied to the surface of a metallic plate and dried to form a lubricating treatment film of 0.5-10μm film thickness. The water-based treating liquid contains at least one kind of resin, which has glass transition temperature of 10-85 deg.C and is water-soluble or water- dispersible or alkali-soluble, and contains <=5.0wt.% colloidal silica or titanate- based coupling agent or aluminum-based coupling agent for the alkali-soluble resin solid content and 0.5-10wt.% metallic soap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal material having a lubricating film having excellent scratch resistance and excellent film removal properties on a surface of a base metal (hereinafter referred to as a surface lubricating metal material).

[0002]

2. Description of the Related Art Thin metal sheets such as steel sheets and plated steel sheets
When plastic working (hereinafter referred to as metal plate), a lubricant such as press oil is applied to the metal plate before processing to improve the lubricity between the mold and the metal plate, and reduce the load applied during processing. Techniques for preventing image sticking and image sticking have been conventionally employed.

However, in recent years, in consideration of environmental problems in applying lubricant and removing the lubricant after processing, and in consideration of reduction of manufacturing cost, a consumer does not apply lubricant at the time of processing. At the metal plate manufacturing stage or at an appropriate stage up to the customer, a solid organic film containing various lubricants in the organic resin (referred to as “lubrication treatment film” in this specification) is applied to the surface of the metal plate in advance. The formed surface lubricated metal plate has come to be widely used. As a result, the consumer can immediately perform the plastic working, which saves labor.
Another advantage is that the quality of the lubricated coating formed is stabilized and homogenized, since the application of the lubricant is carried out on a large scale in specialized equipment.

[0004] Surface lubrication-treated metal plates are roughly classified into a film-deposited type and a non-film-deposited type. After removing the lubricated film by a method such as degreasing after plastic working,
It is used as it is without any treatment or after further chemical conversion treatment and painting. On the other hand, a non-delamination type surface lubricated metal sheet is used without removing the lubricated film after plastic working, with the lubricated film attached, or with further coating applied thereon. Generally, in the case of a metal plate that is made into a final product by making use of its beautiful surface, such as a stainless steel plate or an aluminum-plated steel plate, it is often used as a film-coated surface lubrication-treated metal plate.

[0005] The main performances required of a delamination type lubricating film for plastic working are as follows. Good lubricity even when the film thickness is small. After the film is formed, the films do not easily stick to each other (good blocking resistance). The film can be easily removed by washing.

An acrylic resin, a processing liquid capable of forming such a lubricating film on the surface of a metal plate,
The main component is a dry or bake-curable film-forming component composed of a conventionally known water-soluble or water-dispersible resin such as an epoxy resin, a melamine resin, or a phenolic resin. One or two of soap, fatty acid ester, fatty acid amide, higher alcohol, graphite, molybdenum disulfide, fluororesin powder, etc.
Compounds containing more than one kind of lubricating component have been proposed.

[0007]

However, in the case of a metal plate having a beautiful metallic luster whose surface is polished or brightly annealed, such as the above-mentioned stainless steel plate, severe plastic working such as drawing can be performed. It is not enough to impart lubricity only, and it is required to maintain the original beautiful surface even after removing the lubricating film after processing. If the metal plate of the base material is scratched during processing, the beauty of the surface is greatly impaired.

The conventional lubrication coating film has insufficient scratch resistance, so when the substrate is a metal plate having a beautiful surface such as a stainless steel sheet or an aluminum-based steel sheet,
Instead of forming a lubricating film as described above, a method is generally adopted in which a vinyl film or the like having a thickness of about 80 μm is bonded to the surface of a metal plate to ensure lubricity and a beautiful surface.

However, in this method, it is necessary to peel off the film after the plastic working, and this work must be performed manually, which greatly hinders the automation and labor saving of the production line and raises the cost. In addition, it is often difficult to peel the film particularly at the processed part. Furthermore, the peeled film is bulky and difficult to incinerate in many cases, and requires a great deal of expense for volume reduction and landfill treatment.

[0010] For this reason, there has been a strong demand for the improvement of scratch resistance of a film-coated surface lubricated metal sheet. In this regard, for example, Japanese Patent Application Laid-Open No. Sho 52-104459 discloses that for processing, an organic resin film having a specific composition is provided on both sides, and a lubricating film is further formed thereon on one side on which plastic working is performed. A stainless steel plate is disclosed. JP-A-53-75159 discloses a stainless steel sheet whose surface is coated with a vinyl resin or the like having a specific acid value and a glass transition temperature. However, at present, a metal plate having a lubricating film having a very high scratch resistance required by a consumer such as a home appliance manufacturer has not yet been obtained.

In view of such a situation, the present invention satisfies all the performances required for a lubricating film for plastic working, such as scratch resistance, lubrication, blocking resistance, and film removal. It is another object of the present invention to provide a metal material of surface lubrication treatment of a film removal type.

[0012]

Heretofore, the main concept for preventing surface flaws generated during plastic working has been as follows. (a) Increase the thickness of the lubrication coating to avoid direct contact between the mold and the sheet metal. (b) Improve the lubricity of the lubricating film by adding a solid lubricant or the like, and increase the sliding length until the occurrence of scratches.

However, with a lubricating film based on such a concept, it is difficult to reliably prevent the occurrence of surface scratches on the base metal if the conditions of the plastic working are severe. Accordingly, the present inventors have conducted various studies on the mechanism of surface flaw generation during plastic working, and as a result, the peeled pieces of the lubricating film deposited in the mold due to contact with the material are the causes of surface flaw generation. Was obtained.

That is, no matter how thick a lubricating film having good lubricity is formed, if the adhesion between the film and the base metal is low, the film is exfoliated and the peeled film is deposited on a mold, and the surface is scratched. It is the cause of. Therefore, it has been concluded that the generation of surface flaws can be suppressed by increasing the adhesion between the film and the base metal.

Based on this finding, the present inventors have repeatedly studied the main components and additives of the resin constituting the delamination type lubricating film, and as a result, the conventionally proposed film formation of the main component has been proposed. In addition to the lubricity component (resin) and the lubricating component, an adhesion enhancer that enhances the adhesion between the lubricating coating and the base metal is added to enhance the adhesion between the coating and the base metal, thereby improving the The inventors have found that the scratching property is dramatically improved, and have reached the present invention.

Here, the present invention provides at least one kind of a water-soluble or water-dispersible alkali-soluble resin having a glass transition temperature of 10 ° C. to 85 ° C. 0.5% by weight or less of an adhesion enhancer for enhancing the adhesion between the resin and the substrate,
A scratch-resistant and film-removing film characterized by having a lubricating film having a film thickness of 0.5 μm to 10 μm formed from an aqueous treatment solution containing at least 10% by weight of metal soap. It is an excellent surface lubricated metal material.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The surface lubricating metal material of the present invention and the processing liquid used for forming the lubricating film will be described in detail below. In the following description,% is% by weight unless otherwise specified.

The base metal substrate shape and type of the metal is not particularly limited. As the shape, a thin plate shape which is a main target of plastic working is widely applied as a base metal, and therefore, the present invention will be mainly described below with reference to a metal plate. However, the wire rod,
It is also applicable to pipe materials and the like.

Examples of the type of metal include hot-rolled steel sheets, cold-rolled steel sheets, stainless steel sheets, galvanized steel sheets, aluminum-coated steel sheets, aluminum sheets, titanium sheets and the like. Among them, stainless steel sheets and aluminum-plated steel sheets that are often used unpainted for their beautiful surfaces
(Example: 55% Al-Zn plated steel sheet) is a base metal suitable for maximizing the excellent scratch resistance according to the present invention.

The base metal is used to improve corrosion resistance.
The lubricating film according to the present invention may have a chromate film as a base (particularly, when the base metal is a zinc-based or aluminum-based plated steel sheet).

According to the present invention, a treatment liquid containing an alkali-soluble resin component, a lubricating component and an adhesion enhancer is applied to the surface of a base metal, and the coating film is dried to form an alkali solution ( For example, a film-forming type lubricating film which can be easily removed with a commercially available alkaline degreasing solution) is formed. Next, the components of these treatment liquids will be described.

As a resin component (film-forming component) constituting a main component of the lubricating film, an aqueous treatment solution can be prepared, and the film can be easily removed by washing with an alkali solution. Water-soluble or water-dispersible, alkali-soluble resin is used. Examples of such resins include acrylics,
Examples thereof include water-soluble or water-dispersible resins such as epoxy-based, melamine-based, and phenol-based resins, and can be selected from those conventionally used in water-based paints. These alkali-soluble resins are generally polymers having an acid value in which an acidic group is introduced into a molecule by copolymerizing an acidic monomer or modifying it with an acidic compound. There is no restriction on the polymerization method.

The alkali-soluble resin has a glass transition temperature.
Use a temperature between 10 ° C and 85 ° C. When the glass transition temperature of the resin is less than 10 ° C., the blocking resistance of the coating is insufficient, and the coatings may adhere to each other when they are stacked, and the scratch resistance is also deteriorated. On the other hand, when the glass transition temperature of the resin exceeds 85 ° C., the workability of the film deteriorates. The glass transition temperature is preferably from 15 ° C to 60 ° C.

The alkali-soluble resin preferably has an acid value of 20 or more, more preferably 30 or more. If the acid value is less than 20, the resulting lubricating film may be insufficiently removed by an alkaline solution.

As the alkali-soluble resin, one or more water-soluble or water-dispersible alkali-soluble resins may be used, or at least one water-soluble and water-dispersible alkali-soluble resin may be used. You may use together.

In the present invention, in addition to the resin and the lubricating component, an adhesion enhancer is present in the lubricating coating in order to enhance the adhesion of the lubricating coating to the base metal. Thus, even when severe plastic working such as drawing is performed, peeling of the film is less likely to occur, and generation of scratches due to the peeled film can be prevented, so that scratch resistance is dramatically improved.

As the adhesion enhancer, a compound having a high affinity for both the base metal and the alkali-soluble resin can be used. Examples of such compounds include colloidal silica, titanate-based coupling agents, and aluminum-based coupling agents.

The colloidal silica forms a polysiloxane-type network structure in the film, and thereby adheres to both the base metal and the resin film, thereby improving the adhesion between the two.
Colloidal silica includes wet silica (also called silica sol or colloidal silica) and wet silica (also called fumed silica) synthesized by a gas phase method, and the treatment liquid used for coating in the present invention is an aqueous system. So
Wet silica excellent in dispersibility in an aqueous system is preferable.

The titanate-based coupling agent and the aluminum-based coupling agent have a hydrolyzable group capable of hydrolyzing and reacting with a polar group on the surface of the base metal, and an organic group having a high affinity for the resin. This has the effect of increasing the adhesion between the inorganic base metal and the organic resin. Many types of compounds are known as these coupling agents, and any of them may be used.

One or more of the adhesion enhancers can be used. The amount (in terms of SiO _{2 in} the case of silica sol, the total amount in the case of two or more) is 5.0% or less with respect to the resin solid content. If the compounding amount exceeds 5.0%, the crosslinking of the resin film proceeds remarkably, and the film removing property after plastic working deteriorates. The lower limit is not particularly limited, but is preferably 0.1% or more. A more preferred amount is 0.5 to 3.0
%.

Metal Soap The lubricating film of the present invention contains metal soap as a lubricating component. Examples of the metal soap include aluminum stearate, calcium stearate, zinc stearate, magnesium stearate and the like, but other than these can also be used. Also, two or more kinds can be used. Metal soaps are generally very fine particles and can be dispersed in aqueous treatment liquids.

The amount of the metal soap is based on the solid content of the resin.
0.5% or more and 10% or less. Preferably it is 1 to 5%. If the amount is less than 0.5%, the lubricity becomes insufficient, and
%, The effect of improving lubricity is not only saturated, but also the cohesive strengthening of the resin film is reduced and the scratch resistance is deteriorated.

Lubricated film The surface lubricated metal material of the present invention is prepared by applying an aqueous treatment solution containing the above-mentioned alkali-soluble resin, adhesion enhancer and metal soap to the surface of the base metal and heating it if necessary. To form a lubricated film formed on the surface by drying the film. The thickness of the lubricating film is 0.5 μm or more and 10 μm or less. If it is less than 0.5 μm, the scratch resistance is insufficient, and if it exceeds 10 μm, the problem of film deposition on the mold occurs. The preferred film thickness is 1.0 μm or more and 5.0 μm or less.

When the base metal is a metal plate, the formation of a lubricating film is usually performed on both surfaces of the metal plate. However, depending on the application, the lubricating film may be formed on only one surface.
The method of forming the lubricating film is not particularly limited, but a standard method will be described below.

Pretreatment The treatment liquid used for forming the lubrication treatment film is water-based because the main component resin is a water-soluble or water-dispersible resin.
Therefore, the base metal needs to be sufficiently degreased by alkali degreasing or the like. If the degreasing is insufficient, defects such as repelling or uneven coating are generated on the formed film.

Treatment Solution The treatment solution is a water-soluble or water-dispersible alkali-soluble one.
The aqueous resin liquid containing the seed or two or more kinds may be prepared by first adding a metal soap and sufficiently dispersing the same, then adding an adhesion enhancer, stirring, and, if necessary, diluting. it can. Dilution is performed using ion-exchanged water.
An organic solvent having good compatibility with water (eg, alcohol, ketone, etc.) may be added to improve the wettability and the defoaming / drying properties. The solid content concentration of the treatment liquid is adjusted according to the thickness of the lubricating film to be formed and the application method. In addition to the above components, small amounts of conventional additives such as a dispersant and a surfactant may be added to the treatment liquid. In addition, a colorant (pigment or dye) is added to the treatment liquid to color the coating so that it is easy to identify the treated surface when lubricating only one side of the base metal and to grasp the state of film removal. May be.

The method of applying the treatment liquid varies depending on the shape of the base metal, but in the case of a metal plate, application by a roll coater is most preferable. When a roll coater is used, it is easy to adjust the coating film thickness and beautiful coating is possible. In addition, a spray method, a brush coating method, a dipping method, and the like can be applied. For a substrate having a complicated shape, a spray method, an immersion method or the like is practical.

Drying After applying the treatment liquid, it is dried to form a lubrication treatment film. The drying temperature may be such that the water evaporates, but it is preferable to carry out the drying under the condition that the maximum attained plate temperature is 40 to 100 ° C. As a drying method, a commonly used method such as hot air drying or infrared drying can be applied.

The surface lubricating metal material of the present invention has a strong adhesion between the lubricating film and the base metal, and has excellent scratch resistance. sex,
Excellent blocking resistance.

[0040]

The present invention will be described below in detail with reference to examples.

To a resin solution in which various alkali-soluble resins having a glass transition temperature (Tg) and an acid value shown in Table 1 are dissolved or dispersed in water, metal soap is first added, and the mixture is thoroughly stirred and dispersed. And then add the adhesion enhancer,
An aqueous treatment liquid having a solid content composition shown in Table 2 was prepared.
The total solids concentration of the treatment solution is 20%
Was adjusted. Examples of the adhesion enhancer include wet silica having an average particle diameter of 10 nm (Snowtex 20 manufactured by Nissan Chemical Industries, Ltd.), titanate-based coupling agents (isopropylisostearoyl diacryl titanate, KR11 manufactured by Ajinomoto Co.), and aluminum-based coupling agents (Acetoalkoxyaluminum diisopropylate, AL-M manufactured by Ajinomoto Co.) was used.

This aqueous treatment solution was applied to both surfaces of a stainless steel plate (SUS430, 2B finish, 1.2 mm thick) whose surface was alkali-degreased with a bar coater. After drying for a minute, a test plate was obtained. This test plate was subjected to the following test, and its performance was examined.

Evaluation Test of Scratch Resistance Using a simple sliding test apparatus shown in FIG. 1, a test was performed by sliding the test piece while pressing a polished die against the test piece under the following conditions. The scratches of the part were visually observed, and the scratch resistance was evaluated according to the following criteria. ◎ or ○ indicates good.

Dice polishing paper: # 600 Dice polishing direction: Parallel polishing Pressing pressure: 0.66 Mpa (66 g / mm ² ) Test specimen collection direction: Rolling direction Test specimen shape: 1.2 mm thick × 30 mm width × 150 mm length Moving length: 50 mm

Evaluation Test for Removal of Membrane A commercially available alkaline degreasing solution (FC manufactured by Nippon Parkerizing Co., Ltd.
-L-4480) at a temperature of 40 ° C. and a spray pressure of 1 kg / cm ² for 10 seconds to remove the film.
The presence or absence of water repellency was visually determined, and the film removal property was determined according to the following criteria.で あ れ ば: good

：: No water repelling Δ: Part of water repelling ×: Water repelling occurred on the entire surface.

Evaluation Test of Blocking Resistance The blocking resistance is resistance to adhesion (blocking) between the lubricated coatings during stacking and storage of the lubricated plates. When this sticking occurs, workability is reduced and the efficiency of plastic working is significantly deteriorated.

The test was performed by superimposing the films of two test pieces each having a lubricated film formed only on one side at 40 ° C. and 200 kg.
The adhesive state after being pressed for 3 hours at a pressure of / cm ² and peeled was evaluated according to the following four grades. ◎ or ○ indicates good.

A: Peeled off by its own weight, with no sticking marks.

：: Peeled off by its own weight, but adhesive marks were observed.

△: Adhesive, but peels off when patted lightly.

×: Adhered and did not peel off when hit.

The evaluation results are also shown in Table 2. As is clear from the results, the lubricated metal material of the present invention shown as an example was excellent in scratch resistance, and also good in film removal property and blocking resistance.

[0054]

[Table 1]

[0055]

[Table 2]

[0056]

The surface lubricated metal material of the present invention is excellent in the adhesion of the lubricated film to the base metal, and the film is unlikely to be peeled off even under severe plastic working such as drawing. No surface flaws occur due to contact with the mold during processing, and the film is excellent in film removal and blocking resistance after molding.

[0057] Accordingly, a beautiful material, such as a stainless steel plate or an aluminum-plated steel plate, which is conventionally used without coating after processing, has been conventionally formed by bonding a vinyl sheet to prevent scratches during plastic working. The present invention can be sufficiently applied to a metal material having a smooth surface. Thereby, the workability of the plastic working of such a metal material is remarkably improved, and the problem of disposal of the vinyl sheet is also solved.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a simple sliding test apparatus used for a scratch resistance evaluation test in Examples.

[Explanation of symbols]

1: material, 2: die, 3: holder, 4: load, 5:
Slide table

Claims (2)

[Claims] 1. A glass transition temperature of 10 on a surface of a base metal.
A water-soluble or water-dispersible and alkali-soluble resin having a temperature of not less than 85 ° C and not more than 5.0% by weight based on the solid content of the alkali-soluble resin; With a lubricating film having a film thickness of 0.5 μm to 10 μm, formed from an aqueous treatment liquid containing a water-enhancing agent and a metal soap of 0.5% to 10% by weight. Surface lubricated metal material with excellent properties and film removal. 2. The surface lubricating metal material according to claim 1, wherein the adhesion enhancer is selected from the group consisting of colloidal silica, titanate coupling agents, and aluminum coupling agents.