JPH0445183A - Treatment of adhesive surface of electrically conductive material - Google Patents

Abstract

PURPOSE:To obtain an electrically conductive material having a little mechanical strain, etc., caused by temperature change by applying an electrolyte solution and metal powder to the adhesive surface of electrically conductive material made into a cathode, and electrically depositing a precipitated layer blended with the metal powder through an anode on the adhesion surface. CONSTITUTION:A material impregnated with an electrolyte solution containing a metal cation is brought into contact with the adhesive surface of an electrically conductive material made into a cathode, the electrolyte solution is applied to the adhesive surface, then the adhesion surface is coated with the metal powder and the impregnated material is pressed against the adhesion surface and a stirred. Then, a precipitated layer blended with the metal powder is electrically deposited on the adhesion surface to carry out an adhesion surface treatment of the electrically conductive material. Since the prepared electrically conductive material has minimum thickness of adhesion part and excellent water resistance, the electrically conductive material is suitable for medical and dental treatment setting value on beauty and a device field thereof.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a conductive material that can sufficiently enhance the adhesive effect even at room temperature when applying an adhesive to the surface of a conductive material such as metal. The present invention relates to an adhesive surface treatment method and is suitable for the field of manufacturing and repairing mechanical parts and electrical parts. In particular, there is little mechanical distortion due to temperature changes during bonding, and since it is molded with metal powder, the thickness of the bonded portion is so small that it is almost indistinguishable with the naked eye. It also has excellent water resistance, making it ideal for medical treatment and related equipment fields where aesthetics are important.

<Conventional technology> Conventionally, when bonding conductive materials with an adhesive, the surface of the conductive material to be bonded is heated to a high temperature and an oxide film is formed on the surface in order to increase the adhesive strength between the bonding surface and the adhesive. , a method of producing a deposited thin film using natural oxidation, or a method of electrochemically corroding the surface.
Surface treatment methods such as

<Problems to be Solved by the Invention> However, in any of these conventional techniques, when destructive stress is applied to the bonded part, the mechanical stress is Since the adhesive was concentrated only on the treated area, the overall adhesion effect was not improved.

Now, the present inventor has previously proposed a technique related to a method for joining conductive materials (Japanese Patent Application No. 1-14680), but the present invention was developed in connection with this earlier proposal, and is made smaller by electrolytic fixation of fine metal powder,
Adhesion of conductive materials that increases the apparent area and evenly distributes the mating force and chemical bonding force over the entire surface of the adhesive, thereby absorbing strain forces over the entire surface and improving the adhesive maintenance strength as a whole. This paper aims to provide a surface treatment method.

Means for Solving the Problems〉 In order to achieve the above-mentioned object, the method for treating the adhesive surface of a conductive material according to the present invention applies an electrolytic solution containing metal cations and a metal powder to the adhesive surface of a conductive material that has been made into a cathode. and a deposited layer mixed with metal powder is electrodeposited on the adhesive surface via an anode.

To the best of the applicant's knowledge, there is no knowledge that as a surface treatment for adhesives, metal powder is applied to the adhesive surface of a conductive material using an electrolytic solution, and the surface properties of the adhesive surface are changed to enhance the adhesive effect. not exist.

In particular, there seem to be no examples in which an electrolytic solution and metal powder are pressed against and stirred on an adhesive surface.

In order to improve the adhesion maintenance power of an adhesive, it is required that the adhesive itself has a high cohesive force and that distortion is small during curing, and similar conditions are required for the side to be bonded. In other words, it is required that the cohesive force of the metal powder be as large as the cohesive force of the metal powder, which corresponds to the cohesive force of the adhesive, and that the strain of the metal powder that is deposited during the hardening of the adhesive be as small as possible.

According to the theory of metal electrodeposition, even if it is a metal powder, if the conditions are set, the result of electrodeposition will be a metallic bond and a value close to the cohesive force of metals will be obtained. Furthermore, the distortion of metal during electrodeposition can be kept to a small level by controlling the electric double layer and adjusting the electrolyte.

For this reason, each extremely small metal particle of the metal powder forms its surface by electrodeposition, so the adhesive surface is covered with fixed metal powder, increasing the apparent surface area and creating a surface with less distortion. will be held.

Furthermore, a unique feature of this surface property is that when the fine powder undergoes an electrodeposition reaction in the electrolytic solution by pressure welding and stirring, an electric field is applied between it and the adhesive surface and it becomes charged. . In this way, since the metal powder itself has an electrode potential, each of these powders exhibits extremely complex behavior and is fixed by electrodeposition.

When we specifically observe under magnification the surface properties of the adhesive surface on which this metal powder has been fixed by electrodeposition, we see that it appears to be a more complex "crepe striped pattern" with peaks and valleys, and even overhangs. There are some areas where the adhesive is trapped, so the adhesive gets into these areas and hardens, creating an excellent anchoring effect.

If we try to express such a complex generation process in a simple way, we can think of the following expressions.

That is, the reason why the metal powder is immobilized in a complicated manner on the adhesive surface of the conductive material is the result of the combination of the electrochemical electrodeposition reaction and the adhesion reaction referred to in tribology.

It is obvious that the particle shape and particle size of the metal powder affect the formation of an adhesive surface with properties such as However, at present, it is not always possible to make a unilateral decision on the metal powder side. This has been confirmed.

Regarding the type of metal powder, noble metals such as gold, silver, and palladium are suitable, and base metal materials include copper,
Appropriate materials include nickel, indium, tin, lead, zinc, etc., and alloys such as brass, solder, gold alloy, silver alloy, palladium alloy, stainless steel, etc.

<Function> When an object is bonded to the adhesive surface of a conductive material using an adhesive, the metal powder must be strengthened by electrodeposition reaction so that the adhesive can be effectively bonded to the adhesive surface of the conductive material. It can be immobilized to increase its apparent surface area. Further, pressure welding and stirring can be performed to finely disperse the anchoring effect over the entire surface of the adhesive surface, and the adhesion effect can diffuse and support the destructive stress on the surface texture.

In order to electrodeposit metal powder onto a conductive material, it is necessary to bring the metal powder to the same potential as the cathode potential of the conductive material. Pressure is applied with a ball, etc., and stirring is performed to make electrodeposition effective. Each of these effects corresponds to friction in tribology, and can also be interpreted as lubrication due to the presence of electrolyte. In general, this action can be said to be an adhesion reaction.

As a result of this action, the surface texture of the metal powder after fixation is formed into a "crepe striped" pattern, and with the addition of the electronic reaction of the fine metal powder, a surface with uneven and overhanging shapes is formed. do. In addition, each individual metal powder is composed of bonds similar to strong metal bonds.

<Embodiments> Embodiment 1 Embodiment 1 of the present invention will be described below with reference to the drawings and FIG. 1.

Sample details Conductive material/Copper round bar Diameter 5mm Length 3mm Cross section 100
No. 0 finished cathode conductor wire: Copper wire wire diameter 0.3 mm Conductive material is solder connection format: Conductive material 1 and cathode copper wire 2 are 14 m in diameter
+n, embedded in polyester resin 3 with a height of 8-15M to facilitate tensile shear testing.

Metal powder is placed on the adhesive surface 4 on the upper surface of the conductive material 1, and an electrolytic solution is added, pressure-welded and stirred. An adhesive is applied to the generated surface, and a stainless steel shearing element (not shown) is adhered, and a tensile shear test is performed. The adhesion strength was tested.

In order to understand the effectiveness of the treatment method of the present invention, since adhesives generally adhere strongly to oxide films on metal surfaces, we conducted comparative tests using gold, a metal that does not easily form oxide films. Since this is an example, I decided to follow that method here as well.

Sample materials and data Metal parata, gold, particle size 0.5-1.0μm Amount used: approx. 0.4g Contains gold ions, total concentration 40g/β 1.3V 4-5mA approx. 2 minutes Panavia EX (product name) ■Adhesive made by Kuraray] Adhesive shear Ni stainless steel, 5US-304 diameter 5 mm round bar, length 5 mm Electrolyte solution deposition voltage Deposition current Deposition time Adhesive name Test results: A) Powder according to the present invention If not used Sample number Shear force kg / crtf Electrodeposition time Fracture interface 13
48.5 2 minutes Electrodeposition surface and adhesive surface 14
67.1” 1115
67.7 〃〃Average 61.1 B) When using the powder according to the present invention Sample number Shearing force kg / cal' Electrodeposition time Fracture interface 19
194.3 2 minutes Mixed destruction 20 14
3.2 〃 〃21 111.1
ノ' 〃28 198.0 5
Min. Average: 161.6 As described above, the adhesive strength was improved by 2.65 times by electrodeposition using the powder according to the present invention.

This surface treatment method was performed in the following order.

■ Wash the adhesive surface of the conductive material with detergent EETOREX-14 (trade name) [manufactured by Nippon Electroplating Engineers ■] for 5 minutes, rinse with water, and dry.

■ Connect the conductive material to the cathode.

■ A mold plate was prepared in advance for 2 minutes using a prescribed electrolyte and cotton ball tweezers.

■ Approximately 1/3 of 0.4 g of gold powder was applied to the surface.

■ Immediately connected platinum tweezers with a cotton ball at the tip to the anode.

■ A cotton ball was sufficiently impregnated with the electrolyte.

■ It was pressed onto the gold powder for 2 minutes and stirred. Toward the end, I could feel the electrodeposition of powder.

■ Wipe the electrodeposited surface with a tissue.

Then, I did the same thing as above ■~■ two more times, for a total of three times, and finished (this meant that I had used all of ■). The adhesive surface now exhibited a "crepe striped pattern" as shown in FIG. 3, which was clearly confirmed by microscopic observation.

Example 2 This example uses a mold plate using gold powder as in Example 1, but this example uses the same mold plate but uses tin, which is a base metal, as the powder.

All the conductive materials of the sample were the same as in Example 1, and only the materials will be described below.

Metal powder/tin, particle size 1-30μm, average 10μm
m Usage amount: 0.15 g, divided into 3 times.

Deposition voltage current: 1.3V, 3~4mA Tensile shear test as follows Sample number Shear force kg/ci Electrodeposition time Fracture interface 16 109.8 2 minutes Mixed fracture 1
7 189.5 ” ”18
140.9 〃'' Average 146.7 As shown by this result, there is no big difference even if the deposited metal and the particulate metal are different.

Example 3 Embodiment 3 will be explained below using FIG. 2.

In this example, in addition to the treatment method of electrodepositing the metal powder of the present invention, the effect of natural oxidation of the deposited film was simultaneously realized. That is, in this embodiment, tin, which is easily oxidized naturally, was used instead of gold as the electrolyte. Further, the conductive material 5 with the adhesive surface 6 as the upper surface is not embedded in resin. Furthermore, the adhesion test is a butt joint tension test, not a shear test.

Sample details Conductive material: Copper round bar, diameter 8 mm, length 15 mm Cross-section No. 1000 finished tin, average particle size 10 μm, usage amount 0.15 g 5n-200 (product name) used to divide into two (product name) [Nippon Electroplating Co., Ltd.]・Suzmetuki bath made by Engineers■ 30 g/j2 2.6V Metal powder: Electrolyte: Metal concentration: Electrodeposition voltage: Electrodeposition current: 4 mA Electrodeposition time: Approximately 2 minutes each Adhesive: Panavia EX (product name) ) Butt: 5O3-304, diameter 5 mm, length 15
mm Electrodeposition procedure is omitted as it is based on Example 1.2. The test results are as follows.

Sample number Adhesive force kg/crl Fractured interface In the above description, a bar-shaped (cylindrical) conductive material was used as an example, but a plate-shaped conductive material may be used. Alternatively, a masking tape with holes may be attached to the surface of the plate-shaped conductive material, and the area within the holes may be used as an adhesive surface.

<Effects of the Invention> The method for treating the adhesive surface of a conductive material according to the present invention has the content as described above, and the method for forming the surface of metal powder produced by electrodeposition and adhesion onto the conductive material is as follows. This method can be used very skillfully to finely disperse stress and strain, which has the effect of increasing and maintaining adhesive strength overall. Further, the type of metal deposited and the type of metal in the powder do not necessarily have to be the same, and by combining them, it can be said that the adhesive surface treatment method can be flexibly adapted to the purpose.

Furthermore, all of this can be done at room temperature, the equipment used is small and lightweight, the power consumption is small, and the materials required are small.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a state in which conductive materials according to Examples 1 and 2 of the present invention are embedded in resin, FIG. 2 is a perspective view showing a conductive material according to Example 3 of the present invention, and FIG. The figure is an enlarged photograph showing the particle structure of the metal powder on the adhesive surface of the conductive material, which exhibits a "crepe striped pattern." 1. Conductive material 4. Adhesive surface cathode conductor polyester resin

Claims (9)

[Claims] (1) An electrolytic solution containing metal cations and metal powder are applied to the adhesive surface of a conductive material that has been made into a cathode, and a deposited layer mixed with metal powder is deposited on the adhesive surface via an anode. Adhesive surface treatment method. (2) How to apply the electrolytic solution containing metal cations and the metal powder. First, the impregnated body containing the electrolytic solution is brought into contact with the contact surface of the conductive material to apply the electrolytic solution, and then the electrolytic solution is wetted. 2. The method for treating a bonding surface of a conductive material according to claim 1, wherein a metal powder is applied to the bonded surface in a state where the bonding surface has been bonded, and the metal powder and electrolyte are pressed against the bonding surface by the impregnated body and stirred. (3) To apply an electrolytic solution containing metal cations and metal powder, the metal powder is dispersed in the electrolytic solution in advance, the electrolytic solution in which the metal powder is dispersed is impregnated into the impregnated body, and the impregnation is carried out. 2. The method for treating an adhesive surface of a conductive material according to claim 1, wherein the metal powder and the electrolytic solution are pressed against the adhesive surface and stirred by a body. (4) The method for treating an adhesive surface of a conductive material according to any one of claims 1 to 3, wherein the impregnated body is a brush or a cotton ball. (5) Attach masking tape with holes to expose only the adhesive surface to the surface of the conductive material in advance,
5. The method for treating an adhesive surface of a conductive material according to claim 1, wherein an electrolytic solution containing metal cations and a metal powder are applied to the hole area of the masking tape. (6) The method for treating an adhesive surface of a conductive material according to any one of claims 1 to 5, wherein the metal powder has a particle size of 0.1 to 250 μm. (7) The method for treating an adhesive surface of a conductive material according to any one of claims 1 to 6, wherein the metal powder is a noble metal. (8) The method for treating an adhesive surface of a conductive material according to any one of claims 1 to 6, wherein the metal powder is a base metal. (9) The method for treating an adhesive surface of a conductive material according to any one of claims 1 to 8, wherein the conductive material is a nonmetal with at least the adhesive surface made conductive.