JP3153978B2 - Chromium-containing foil with excellent adhesion to resin or paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chromium-containing foil typified by a stainless steel foil, which is increasing in demand in various fields including electronics, and more particularly to a chromium-containing foil capable of ensuring good adhesion to a resin or a paint. It relates to the contained foil.

[0002]

2. Description of the Related Art Conventionally, the following methods have been mainly studied for the adhesion of a chromium-containing foil such as a stainless steel foil to a resin or paint. (1) A method of controlling the roughness of the surface of the material; a method of increasing the contact surface between the material and the resin or the paint as much as possible, that is, a method of improving the adhesion by utilizing a so-called anchor effect. (2) Consideration from the viewpoint of resin or paint; a method of introducing a functional group capable of ensuring good adhesion to a material into resin or paint.

[0003] However, in the current situation where the application of the chromium-containing foil in the electronics field is increasing, an example has emerged in which sufficient adhesion cannot be ensured by the above method alone. This means that the use conditions become severe, and the resin adhesion or paint adhesion secured by the conventional method is insufficient. The stricter use conditions referred to here are, in particular, a reduction in the thickness of the chromium-containing foil used. In order to reduce costs and reduce the weight and size of electronic components, the thickness of the chromium-containing foil used has been steadily reduced. For example, in the past, a 30 μm material was used for an application that was used at 50 μm, and a case where a 15 μm material was used for an application that was used at 30 μm could occur.
It's actually happening.

[0004] When the thickness of the material is reduced, the curvature in the processed portion becomes smaller and the stress concentration on the processed portion becomes larger than in the case where the plate thickness is large, even if the same bending is performed. The phenomenon of peeling off at the interface with the paint frequently occurs.

[0005]

The reason why the adhesion of the chromium-containing foil to the resin or paint is insufficient is considered as follows. It is difficult to ensure the adhesion between the chromium-containing foil and the resin or paint unless the mutual functional groups at the interface form a strong chemical bond. In particular,
At the interface between the two, the hydroxyl group (-OH) is converted to -O-
If a bond is formed, good adhesion can be ensured.

However, although a functional group such as a hydroxyl group effective for adhesion is introduced into a resin or a paint, such a functional group does not exist on the surface of the chromium-containing foil.
An object of the present invention is to provide a chromium-containing foil that can improve the adhesion of a chromium-containing foil, such as a stainless steel foil, to a resin or a paint in view of the current situation.

[0007]

The gist of the present invention is as follows. (1) Cr content: 1 to 30% by weight, plate thickness: 1 to 150
on either side or both sides of the chromium-containing foil [mu] m, per side metallic chromium: 2 to 100 mg / m ^2, hydrated chromium oxide in terms of chromium: adhesion to the resin or coating material, characterized in that it has a 2 to 50 mg / m ² Chromium-containing foil with excellent properties. (2) Cr content: 1 to 30% by weight, plate thickness: 1 to 150
Ni: 100 to 1000 mg / m ² per one side on both sides or one side of a μm chromium-containing foil, and further on the upper layer, metallic chromium: ² to 100 mg / m ² , chromium oxide hydrated: 2 to 50 mg / M ² , a chromium-containing foil having excellent adhesion to a resin or paint.

Hereinafter, the present invention will be described in detail. The chromium content of the chromium-containing foil used is defined as 1 to 30% by weight. This is because if the chromium content is less than 1%, sufficient corrosion resistance cannot be ensured according to the use environment, and the chromium content is 3%.
If it is more than 0%, the effect of improving corrosion resistance will be saturated and it will be economically disadvantageous. Other components, such as nickel and molybdenum, are not particularly specified.

The thickness of the chromium-containing foil is 1 to 150 μm.
m, preferably 5 to 100 μm. this is,
If the thickness of the chromium-containing foil is less than 1 μm, sufficient material strength cannot be secured, and if the thickness is more than 150 μm, the advantages of cost reduction, weight reduction, and miniaturization cannot be exhibited. The present invention does not specify how to produce these chromium-containing foils.

Next, a surface treatment technique for improving the adhesion of the chromium-containing foil to a resin or paint will be described. As described above, the reason why the adhesion of the chromium-containing foil cannot be ensured is that a functional group effective for improving the adhesion, for example, a hydroxyl group is not present on the surface thereof, and these functional groups are added to the surface of the chromium-containing foil. If introduced, it is possible to ensure good adhesion. This can be achieved by uniformly applying a hydrated chromium oxide coating on the surface of the chromium-containing foil.
Hydroxyl groups effective for improving adhesion are present on the surface of the hydrated chromium oxide layer, and can form good adhesion by chemically bonding with hydroxyl groups from resin or paint.

The appropriate amount of hydrated chromium oxide that can ensure good adhesion is defined as ² to 50 mg / m ² . This is because if the amount of hydrated chromium oxide is less than 2 mg / m ² , the amount of hydroxyl groups contained in the hydrated chromium oxide is insufficient, so that a sufficient adhesion improving effect cannot be obtained. On the other hand, if the amount of hydrated chromium oxide is more than 50 mg / m ² , the effect of improving the adhesion is saturated and defects such as deterioration of appearance appear.

Furthermore, if there is no metal chromium layer below the hydrated chromium oxide layer, it is difficult to ensure good uniformity and coverage of the hydrated chromium oxide film, and it is difficult to ensure high adhesion. The amount of chromium metal is defined as ² to 100 mg / m ² . The reason is that if the amount of chromium metal is less than 2 mg / m ² , a uniform hydrated chromium oxide film cannot be secured, and if it exceeds 100 mg / m ² , the effect is saturated and economic disadvantage is caused. It is.

The present invention does not particularly define a method for applying the hydrated chromium oxide layer and the metal chromium layer.
Industrially, cathodic treatment in a chromic acid-based aqueous solution is preferred. However, when applying these hydrated chromium oxide layers and chromium metal layers, a chromium oxide layer generated in the air already exists on the surface of the chromium-containing foil, and a uniform chromium metal layer and hydrated chromium oxide layer are applied. For this purpose, it is effective to have a Ni layer as a base. When a Ni layer is applied under the chromium metal layer, the surface of the chromium-containing foil becomes chemically active uniformly, and it becomes extremely easy to obtain a uniform chromium metal layer and a hydrated chromium oxide layer by electrolytic treatment. It is possible to secure stable adhesion.

An appropriate amount of Ni is 100 to 1000 mg /
m ² . This is because when the amount of Ni is less than 100 mg / m ^2, it is difficult to secure a uniform chromium metal layer and a hydrated chromium oxide layer. When the amount of Ni is more than 1000 mg / m ² , the effect is saturated and economically disadvantageous. Because. Whether these surface treatments are performed on the chromium-containing foil on one side or on both sides may be determined according to the intended use, and are not particularly specified in the present invention.

[0015]

Embodiments of the present invention will be described below. The adhesion between the chromium-containing foil and the resin or paint was evaluated by the following T-peel method. In the case of single-sided treatment, a resin or paint was pressed against the surface-treated surface to evaluate the adhesion. In the case of resin; a modified PP resin having a thickness of 100 μm is pressed on one side of a chromium-containing foil at 250 ° C. for 10 seconds, and
A test piece was prepared by pressing the resin surfaces together at 300 ° C. for 10 seconds. In the case of paint; 60 mg /
dm ² and paint with epoxy phenolic paint, 205
After baking at 10 ° C. for 10 minutes, a nylon-based adhesive was further put between the painted surfaces and pressed at 210 ° C. for 5 minutes to prepare a test piece.

Alternatively, a test piece prepared under the conditions
mm width, and both ends were subjected to a peel test at a tensile speed of 10 mm / min in a T-shape using a tensile tester,
The adhesion was evaluated. The value of the T-peel strength showing good adhesion was aimed at 2.5 kg / 15 mm or more. In addition to the adhesion to the resin and the paint, the appearance of the material was evaluated as required.

Example 1 Ni: 350 mg / m ² , metallic chromium on both sides of a chromium-containing foil made of Cr—Ni stainless steel having a Cr content: 18% by weight, a Ni content: 8% by weight, and a plate thickness: 10 μm : 55 mg / m ² , hydrated chromium oxide: 20 mg / m ²
When a resin was pressed against the material subjected to the above test and the T-peel strength was measured, it showed an adhesion of 3.3 kg / 15 mm.

Example 2 Cr-based steel having a Cr content of 25% by weight and a plate thickness of 55 μm.
Chromium metal: 8 on both sides of chrome-containing foil made of stainless steel
5mg / m^Two, Hydrated chromium oxide: 43 mg / m ^TwoGiving
When the T-peel strength was measured by pressing resin onto the
It showed an adhesion of 4.3 kg / 15 mm.

Example 3 Ni: 102 mg / m2 on one side of a chromium-containing foil made of low alloy steel having a Cr content of 1.1% by weight and a plate thickness of 150 μm.
² , chromium metal: 2.2 mg / m ² , hydrated chromium oxide:
The paint applied to 2.3 mg / m ² of the applied material was pressed and the T-peel strength was measured. As a result, it was found that the adhesiveness was 2.8 kg / 15 mm.

EXAMPLE 4 One side of a chromium-containing foil made of Cr-based stainless steel having a Cr content of 13% by weight and a plate thickness of 1.2 μm was coated on one side with chromium metal
2.2 mg / m ² , hydrated chromium oxide: 2.3 mg / m ²
The coating material was press-bonded to the material to which T was applied, and the T-peel strength was measured. As a result, an adhesion of 2.6 kg / 15 mm was shown.

Example 5 Cr content: 18% by weight, Ni content: 8% by weight, Mo
Content: 2% by weight, plate thickness: 30 µm Cr-Ni-Mo
Ni: 9 on both sides of a chromium-containing foil made of austenitic stainless steel
A resin was pressed against a material on which 90 mg / m ² , metallic chromium: 95 mg / m ² , and hydrated chromium oxide: 48 mg / m ² were applied, and the T peel strength was measured to be 3.9 kg / 15 mm.
Showed the adhesion.

Example 6 Ni: 670 mg / m ² , metallic chromium: 36 mg / m ² , hydrated chromium oxide on both sides of a chromium-containing foil made of a low alloy steel having a Cr content: 5% by weight and a plate thickness: 15 μm 12mg
/ M ² , the coating was pressed and the T-peel strength was measured to show an adhesion of 3.7 kg / 15 mm.

Comparative Example 1 Ni: 85 mg / m ^{2 on} both sides of a chromium-containing foil made of a Cr-Ni high alloy steel having a Cr content of 32% by weight, a Ni content of 8% by weight and a sheet thickness of 0.9 μm. , Metal chrome:
1.8 mg / m ² , hydrated chromium oxide: 1.9 mg / m ²
When a resin was pressed against the material subjected to the test and the T-peel strength was measured, it showed only an adhesion of 1.8 kg / 15 mm.

Comparative Example 2 Ni: 1020 mg / Ni on one side of a chromium-containing foil made of low alloy steel having a Cr content: 0.8% by weight and a plate thickness: 160 μm.
A resin was pressed against a material on which m ² , metallic chromium: 103 mg / m ² , and hydrated chromium oxide: 53 mg / m ² were applied, and T peel strength was measured. As a result, an adhesion of 3.4 kg / 15 mm was shown. The corrosion resistance, particularly the rust resistance at the end face of the material, was not sufficient, and the surface of the material was brownish and the appearance was poor.

[0025]

According to the present invention, the adhesion of a chromium-containing foil to a resin or a paint is greatly improved, so that it can be applied to various fields including the electronics field.

Continuation of front page (72) Inventor Hideo Kanno 1-6 Kojimachi, Chiyoda-ku, Tokyo Nippon Steel Technical Information Center (56) References JP-A-61-284530 (JP, A) JP-A-61-257420 ( JP, A) JP-A-62-218599 (JP, A) JP-A-1-301399 (JP, A) JP-A-1-225794 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , (DB name) C25D 11/38

Claims (2)

(57) [Claims] 1. Cr content: 1 to 30% by weight, plate thickness: 1
A chromium-containing foil having a chromium content of ^{2 to} 100 mg / m ² , chromium oxide hydrate: ² to 50 mg / m ² per side, Chromium-containing foil with excellent adhesion. 2. Cr content: 1 to 30% by weight, thickness: 1
Ni: 100 to 1000 mg / m ² per side on both sides or one side of a chromium-containing foil of up to 150 μm, and further, a metal chromium: ² to 100 mg / m ² , and a hydrated chromium oxide: A chromium-containing foil having excellent adhesion to a resin or paint, characterized by having 50 mg / m ² .