JP3006455B2 - Lubricated metal material with excellent galling resistance and film removal - Google Patents

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 mold resistance and film removal properties on the surface of a base metal.

[0002]

2. Description of the Related Art Conventionally, there has been a technique for improving the lubricity between a metal mold and a metal plate by using a lubricant during plastic working of a metal plate to reduce a load applied during processing and to prevent image sticking. Used. However, in recent years, in order to deal with environmental issues, such as treatment of lubricant after use, and to reduce costs, rather than applying a lubricant such as press oil at the time of processing, the metal plate manufacturing stage, Or, at an appropriate stage before handing over to a consumer, a lubricated metal plate in which a solid organic film containing various lubricants (hereinafter, referred to as “lubricating film”) is preliminarily applied to the metal plate surface is often used. It has become

[0003] Such lubricated metal sheets are roughly classified into two types: a metal film type of a film removal type and a metal plate of a non-film removal type.
Demetallized lubricated metal sheet is a metal sheet that is used after removing the lubricated film by a method such as degreasing after plastic working, and then used without any treatment or after further chemical conversion treatment and painting. is there. On the other hand, with a non-delamination type lubricated metal plate, without removing the lubricated film after plastic working,
The film surface is used as it is or after being further coated.

[0004] Generally, in the case of a material that is made into a final product by making use of its metallic luster, such as a stainless steel plate or an aluminum plate, it is often used as a film-type lubricated metal plate.

[0005] The main performance required of such a delamination type lubricating film for plastic working is the following performance.

[0006] The thin film shows good lubricity.

[0007] Even when the molded films are brought into close contact with each other, the films do not stick to each other (have blocking resistance).

[0008] The film is easily removed.

As a lubricating film agent capable of forming such a lubricating film on the surface of a metal plate, a lubricating component such as an acrylic resin, an epoxy resin or a melamine resin may be used. As fatty acids, fatty acid salts, fatty acid metal soaps, fatty acid esters, fatty acid amides,
Compounds containing higher alcohol, graphite, molybdenum disulfide, fluororesin powder, and the like have been proposed.

[0010]

However, in the case of the above-mentioned stainless steel plate, especially a metal plate having a beautiful appearance whose surface is polished or brightly annealed, it is not sufficient to be able to form only by drawing or the like. Therefore, it is important to prevent mold seizure by the mold and to maintain a beautiful surface in the processed portion.

For this reason, a method of pasting a vinyl film having a thickness of about 50 μm to a metal plate before processing, followed by press molding or the like, and then peeling the film is frequently used. However, in this case, the peeling of the film after processing must be performed manually, which hinders automation and labor saving of the production line. In addition, it is often difficult to peel the film particularly at the processed part. Furthermore, the peeled film is bulky, and in many cases, it is difficult to incinerate it, and a large amount of expense is required for volume reduction and landfilling.

[0012] Therefore, there is a strong demand for improvement of the mold galling of a metal film of a stripped lubrication treatment.
No. 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 that satisfies a high level of anti-galling property required by a consumer such as a home appliance manufacturer has not yet been obtained.

The present invention has been made in view of such a situation, and its object is to provide all the performances required at the time of plastic working, such as mold resistance, lubrication, blocking resistance, and film removal. To obtain a lubricated metal material satisfying the following.

[0014]

The conventional concept for preventing mold seizure is as follows.

(A) The thickness of the lubricating film is increased to avoid direct contact between the mold and the metal.

(B) The lubricity of the lubricating film is improved by adding a solid lubricant or the like, and the sliding length up to galling is increased.

However, even if such a lubricating film design is performed, galling occurs under severe processing conditions. The present inventors have conducted experiments using model experiments and actual presses,
It has been found that the peeled pieces of the lubricating film deposited in the mold due to galling cause the galling of the mold. That is, no matter how thick a film having good lubricity is formed, if the adhesion of the film is poor, the film is peeled off from the root, and the peeled film further causes mold seizure. Therefore, it was concluded that enhancing the adhesion between the film and the base metal is the most important point for preventing mold galling.

The present inventors have repeatedly studied the main components and additives of the resin constituting the delamination type lubricating film, and as a result, added a coupling agent to the lubricating film, It has been found that the mold galling resistance is dramatically improved by enhancing the adhesion to metal.

The present invention has been made based on such findings, and the gist lies in the following lubricated metal materials.

A glass transition temperature of 10 on the surface of the base metal
At least one water-soluble at least 85 ° C and / or
Or a water-dispersible acrylic resin, a silane coupling agent in an amount of 0.2 to 5% by weight and a metal soap in an amount of 0.5 to 10% by weight based on the solid content of the acrylic resin. A lubricated metal material having excellent anti-galling and film-removing properties, characterized by having a lubricated film having a film thickness of 0.8 μm or more and 4 μm or less formed by applying and drying a treating agent.

[0021]

The lubricating metal material of the present invention will be described below in detail.

Base metal: The shape and type of the metal which is the base of the lubricated metal material of the present invention are not particularly limited. However, a thin plate-shaped material mainly used as an object of plastic working is widely applied as a base metal.

Examples of the type of metal include a hot-rolled steel sheet, a cold-rolled steel sheet, a plated steel sheet, a stainless steel sheet, and an aluminum sheet.

Substrate resin: The acrylic resin constituting the lubricated coating of the lubricated metal material of the present invention is a water-soluble or water-dispersible thermoplastic acrylic resin which is generally used for paints. I just need. There is also no limitation on the polymerization method for producing these resins (for acrylic resins and their production methods, see, for example, Kyozo Kitaoka, “Introduction to Paint Synthetic Resins” (published by Kobunshi Kankokai)).

The acrylic resin is obtained by polymerizing a monomer selected from a vinyl unsaturated carboxylic acid and a vinyl unsaturated carboxylic acid ester. These monomers include acrylic acid, methacrylic acid, sorbic acid, itaconic acid, maleic acid, fumaric acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, Butyl (meth) acrylate, isobutyl (meth)
Acrylate, 2-ethyl-hexyl (meth) acrylate, hexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate,
Examples include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycidin (meth) acrylate, and dimethylaminoethyl (meth) acrylate.

In order to polymerize these acrylic monomers, a monomer mixture of at least two components consisting of at least one vinyl unsaturated carboxylic acid and at least one vinyl unsaturated carboxylic acid ester is generally used. And may be performed by a usual method such as a solution polymerization method or an emulsion polymerization method. A polymer having a desired acid value can be obtained by adjusting the ratio of the unsaturated carboxylic acid component in the monomer mixture.

The glass transition temperature (Tg) of the polymer can be set to a desired value by appropriately selecting the components of the carboxylic acid and the carboxylic acid ester and appropriately adjusting the proportions of the components. The acid value and Tg can also be adjusted by blending the polymer. The polymer can be neutralized with ammonia or an amine to improve the stability of the coating composition.

The acrylic resin used in the lubricated metal material of the present invention needs to have a glass transition temperature of 10 ° C. or more and 85 ° C. or less. When the glass transition temperature is less than 10 ° C., the blocking resistance of the film is insufficient, and there is a possibility that the films adhere to each other when they are stacked,
The galling resistance also deteriorates. On the other hand, the glass transition temperature is 85
If the temperature exceeds ℃, the workability of the film is deteriorated.

The acrylic resin used in the present invention preferably has an acid value of 20 or more. Acid number 20
If the amount is less than the above, there is a possibility that the obtained lubricating film may have insufficient film removal property with an alkali solution.

The lubricated metal material of the present invention may be one in which one or more water-soluble acrylic resins or one or more water-dispersible acrylic resins are used. Acrylic resin of both properties
An acrylic resin containing more than one kind may be used.

Silane Coupling Agent: As described later, the lubricated metal material of the present invention is prepared by applying a resin solution obtained by dissolving or dispersing an acrylic resin in water to a surface of a base metal as a treating agent, and drying. This resin liquid contains a silane coupling agent.
This silane coupling agent has the function of enhancing the adhesive strength between the resin film and the base metal, thereby greatly improving the anti-seizing property. In particular, a polyfunctional silane coupling agent can also be expected to have the effect of promoting internal crosslinking of the resin.

Content of silane coupling agent (addition amount)
Is required to be not less than 0.2% by weight and not more than 5% by weight based on the solid content of the resin. If the amount is less than 0.2% by weight, the effect of improving the anti-galling property is insufficient.
If the content is more than 10% by weight, the effect is saturated, which is not only economically disadvantageous but also impairs the stability of the resin solution in which the resin is dissolved or dispersed, and may cause gelation in a short time. A preferable addition amount is 1% by weight or more and 3% by weight or less.

The type of the silane coupling agent to be added is not particularly limited. For example, vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxy Silane, 3-glycidoxypropyltrimethoxysilane, 3
-Methacryloxypropyltrimethoxysilane and the like.

Metal soap: The above resin solution contains metal soap in addition to the silane coupling agent. Metal soap has both lubricating and water repellent effects, but the content (addition amount) is 0.5
If the amount is less than 10% by weight, the lubricity becomes insufficient.
When the content is more than 10% by weight, not only the effect of improving lubricity is saturated, but also the cohesive strength of the resin film is reduced, and the anti-galling property is deteriorated.

Accordingly, it is necessary that the amount of the metal soap added is 0.5% by weight or more and 10% by weight or less based on the solid content of the resin. Preferably, it is 1% by weight or more and 5% by weight or less.

Examples of the metal soap include aluminum stearate, calcium stearate, zinc stearate, magnesium stearate and the like.

Lubrication treatment film: The lubrication treatment metal material of the present invention is obtained by applying a treatment agent containing the above-mentioned acrylic resin, silane coupling agent and metal soap to the surface of the base metal,
The metal material having the formed lubricating film has a thickness of 0.8 μm or more and 4 μm or less. If it is less than 0.8 μm, the mold galling resistance is insufficient, and if it is more than 4 μm, a problem of film deposition on the mold occurs.

The method of forming the lubricating film is not particularly limited, but a standard method will be described below.

[Pretreatment] Since the treating agent used for forming the lubricating film is an aqueous one in which an acrylic resin or the like is dissolved or dispersed in water, the base metal is sufficiently degreased by alkali degreasing or the like. Must be in state. If the degreasing is insufficient, defects such as repelling of the coating are generated in the formed film.

[Treatment Agent] The treatment agent is prepared by first adding a metal soap to a resin solution controlled so as to exhibit a predetermined glass transition temperature and a preferable acid value and sufficiently dispersing it. Prepared by adding and stirring. If the silane coupling agent is added first, foaming may occur, which may hinder preparation. During preparation,
The dilution is performed using ion-exchanged water, but an organic solvent having good compatibility with water may be added to improve the wettability and the defoaming / drying properties. The solid concentration of the treating agent is adjusted by the thickness of the lubricating film to be formed and the application method.

[Application of treatment agent] The method of applying the treatment agent varies depending on the shape of the base metal. In the case of a plate shape, 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. In particular, a spray method or the like is practical for those having a complicated shape.

[Drying] After applying the treating agent, it is dried to form a lubricating film. The drying temperature may be such that water evaporates, but the maximum attained plate temperature is 40 ° C to 100 ° C.
It is efficient and preferable to carry out under the following conditions. As a drying method, a commonly used method such as hot air drying or infrared drying can be applied.

The lubricated metal material of the present invention has a strong adhesion between the lubricated film and the base metal, and has excellent anti-seizure properties. sex,
Excellent blocking resistance.

[0044]

EXAMPLE A silane coupling agent and metal soap were added to a monomer composition shown in Table 1 and various acrylic resins having a glass transition temperature (Tg) and an acid value, and the solid content shown in Table 2 was obtained. A treating agent having a composition was prepared. The total solid content of the treating agent was adjusted to 20% by weight, and adjusted by adding ion-exchanged water.

This treating agent was applied to both sides of a stainless steel plate (SUS430J1L, 2B finish, plate thickness 1.2 mm) whose surface was alkali-degreased with a bar coater, and was heated in a hot-air oven so that the maximum attained plate temperature was 60 ° C. After drying, a test plate was obtained.

This test plate was subjected to the following tests to examine its performance.

[Determination galling resistance test] Using a high surface pressure U molding die as shown in FIG. 1, a mold galling test was conducted under the following conditions, and the scratches on the sliding portion were visually observed to determine the following. The galling resistance was evaluated according to the standard.

◎ or ○ indicates good.

Bead polishing paper: # 600 Bead polishing direction: Parallel polishing Pressing pressure: 379.5 MPa (33 kg / m)
m ² ) Specimen sampling direction: Rolling direction Specimen shape: width 30 mm × length 260 mm Molding height: 70 mm Visual judgment criteria ：: Completely intact ○: Minor scratches (no problem in appearance) △: Mild scratches (appearance) ×: Clear scratches generated [Delamination test] A 2% aqueous solution of an alkaline degreasing solution (“FC4326” manufactured by Nippon Parkerizing) was used at a temperature of 60%.
After film removal by spraying at 10 ° C. and a spray pressure of 1 kg / cm ² for 10 seconds, the presence or absence of water repellency was examined, and the film removal property was evaluated according to the following criteria.で あ れ ば: good

：: No water repelling △: Part of water repelling ×: All over the surface of water repelling [Blocking resistance test] The blocking resistance test is the adhesion (blocking) between lubricated coatings during stacking and storage of lubricated plates. This is a test to examine the resistance to When this sticking occurs, workability decreases and plastic workability deteriorates.

The test was performed by superimposing the films of two test pieces having a film formed only on one side at 40 ° C. and 200 kg.
After pressing for 3 hours at a pressure of / cm ² , it was peeled off, and the adhesion state was evaluated on the following four scales. ◎ or ○ indicates good.

◎: Peeled off by its own weight and no sticky marks ○: Peeled off by its own weight, but sticky marks were observed △: Sticky, but peeled off by tapping ×: Sticky, not peeled off by tapping Test 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 mold seizure resistance, and also good in film removal property and blocking resistance after molding.

[0053]

[Table 1]

[0054]

[Table 2]

[0055]

EFFECT OF THE INVENTION The lubricated metal material of the present invention has no problem of mold seizure by a metal mold during plastic working, and is excellent in the film-removing property and the blocking resistance after molding. It can be used instead of a metal material that has been molded.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of a mold for a high surface pressure U-forming test used in an anti-galling test in Examples.

[Explanation of symbols]

 1: material 2: punch 3: plate holder 4: die 5: round beat (tool roughness setting section)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B32B 15/08 B05D 7/14

Claims (1)

(57) [Claims] 1. The method according to claim 1, wherein the surface of the base metal has a glass transition temperature of 10
At least one water-soluble at least 85 ° C and / or
Or a water-dispersible acrylic resin, a silane coupling agent in an amount of 0.2 to 5% by weight and a metal soap in an amount of 0.5 to 10% by weight based on the solid content of the acrylic resin. A lubricated metal material having excellent anti-galling and film-removing properties, characterized by having a lubricated film having a film thickness of 0.8 μm or more and 4 μm or less formed by applying and drying a treating agent.